A Finite Cluster Approach to the Electron-Hole Pair Damping of the Adsorbate Vibration: CO Adsorbed on Cu(100)

Abstract: A finite cluster method is applied to describe the energy transfer from the adsorbate vibrations to the electron-hole pair excitations. For CO stretch vibration on Cu(100) surface a value of 0.5 meV is found for the consequent damping (corresponding to the lifetime of 1.3·10 -12 s) in an agreement with a recently measured vibrational line width. The mechanism behind the electron-hole pair excitations is found to be charge oscillations between the molecular 2π * resonance and the substrate, caused by the molecular vibration. Cluster size effects have been found to be negligible.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Chalmers University of Technology, University of California, Santa Barbara
Contributors: Rantala, T. T., Rosén, A., Hellsing, B.
Number of pages: 9
Pages: 173-181
Publication date: 1986
Peer-reviewed: Yes

Publication information

Journal: Studies in Surface Science and Catalysis
Volume: 26
Issue number: C
ISSN (Print): 0167-2991
Original language: English
ASJC Scopus subject areas: Condensed Matter Physics, Catalysis, Physical and Theoretical Chemistry, Materials Chemistry, Surfaces, Coatings and Films
Source: Scopus
Source ID: 77956976821

Research output: Contribution to journalArticleScientificpeer-review

Sorption and retention of ethylene glycol monoethyl ether (EGME) on silicas

Sorption of ethylene glycol monoethyl ether (EGME) was studied gravimetrically and correlated with the results of retention experiments where samples wetted with EGME were evacuated. If a sorption measurement is done conventionally by increasing the vapor pressure slowly by small steps, molecules are packed smoothly along the surface, and a fairly flat isotherm is obtained. If the sample is directly exposed to a high vapor pressure or the normal sorption mode is disturbed by directly reducing the pressure, more EGME is sorbed. Then some of the molecules may be fixed only at their hydroxy ends. The evacuation curves are best interpreted in a semilogarithmic form, by which the value of the monolayer capacity can be estimated. EGME can be used for surface area measurements of silicas, but with porous samples areas that are too large are probably obtained. When EGME is packed smoothly on standard silica TK 800, one molecule occupies an area of 0.44 nm2, computed by the BET equation with three parameters, or 1 mg of EGME covers 3.0 m2.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Rakennetekniikka, Tampere University of Technology, University of Tampere
Contributors: Kellomäki, A., Kuula-Väisänen, P., Nieminen, P.
Number of pages: 6
Pages: 373-378
Publication date: 1989
Peer-reviewed: Yes

Publication information

Journal: Journal of Colloid and Interface Science
Volume: 129
Issue number: 2
ISSN (Print): 0021-9797
Original language: English
ASJC Scopus subject areas: Colloid and Surface Chemistry, Physical and Theoretical Chemistry, Surfaces and Interfaces
Source: Scopus
Source ID: 45149145866

Research output: Contribution to journalArticleScientificpeer-review

Thermophilic anaerobic digestion of source-sorted household solid waste: the effects of enzyme additions

Thermophilic (55° C) methanation of source-sorted household solid waste (HSW) was studied in batch and in continuous experiments. Furthermore, the effects of additions of xylanase, lipase, protease and a mixture of these on the methanation were tested. In the batch studies, comparative assays with active and inactive enzymes were used to elucidate the role of the added enzymes. The results showed that the HSW was readily digestible, up to 400-590 mlCH4·g-1 volatile solids (VS) was produced. Only with protease added, at a concentration of 1.1 Anson protease units·kg-1 VS was a higher specific methanogenic activity found with active enzymes compared to inactive (autoclaved) enzymes or without enzyme addition. The methane yield by conversion of the HSW in the batch assays and in the reactor studies was not increased by enzyme additions (enzyme mixture).

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: The Anaerobic Microbiology/Biotechnology Group, Department of Biotechnology, Danmarks Tekniske Universitet, DTU Informatik
Contributors: Rintala, J. A., Ahring, B. K.
Number of pages: 4
Pages: 916-919
Publication date: Feb 1994
Peer-reviewed: Yes

Publication information

Journal: Applied Microbiology and Biotechnology
Volume: 40
Issue number: 6
ISSN (Print): 0175-7598
Original language: English
ASJC Scopus subject areas: Microbiology (medical), Microbiology, Bioengineering, Biotechnology
Source: Scopus
Source ID: 0028258804

Research output: Contribution to journalArticleScientificpeer-review

A two-stage thermophilic anaerobic process for the treatment of source sorted household solid waste

Hydrolysis and acidification of source sorted household solid waste (SSHSW) at 70°C was studied using continuous stirred tank reactor (CSTR). The soluble COD/total initial COD-ratio of the SSHSW increased from 25 to 35% during the CSTR treatment. A thermophilic (55°C) upflow anaerobic sludge blanket (UASB) reactor removed up to 80% of the COD in the liquid fraction of the SSHSW treated at 70°C.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: The Anaerobic Microbiology/Biotechnology Group, Department of Environmental Science and Engineering, Danmarks Tekniske Universitet, DTU Informatik
Contributors: Rintala, J. A., Ahring, B. K.
Number of pages: 6
Pages: 1097-1102
Publication date: Oct 1994
Peer-reviewed: Yes

Publication information

Journal: Biotechnology Letters
Volume: 16
Issue number: 10
ISSN (Print): 0141-5492
Original language: English
ASJC Scopus subject areas: Microbiology, Applied Microbiology and Biotechnology, Bioengineering, Biotechnology
Source: Scopus
Source ID: 0028036651

Research output: Contribution to journalArticleScientificpeer-review

Start-up and Operation of Laboratory-Scale Thermophilic Upflow Anaerobic Sludge Blanket Reactors Treating Vegetable Processing Wastewaters

Thermophilic anaerobic treatment of hot vegetable processing wastewaters was studied in laboratory-scale UASB reactors at 55°C. The high-strength wastewater streams, deriving from steam peeling and blanching of carrot, potato and swede were used. The reactors were inoculated with mesophilic granular sludge. Stable thermophilic methanogenesis with about 60% COD removal was reached within 28 days. During the 134 day study period the loading rate was increased up to 24 kg COD m-3 day-1. High treatment efficiency of more than 90% COD removal and concomitant methane production of 7.3 m3 CH4 m-3 day-1 were achieved. The anaerobic process performance was not affected by the changes in the wastewater due to the different processed vegetables. The results demonstrated the feasibility of thermophilic anaerobic treatment of vegetable processing wastewaters in UASB reactors.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Faculty of Science and Environmental Engineering, Tampere University of Technology, University of Jyväskylä, Jyväskylän yliopisto, Aalto University
Contributors: Lepistö, S. S., Rintala, J. A.
Number of pages: 9
Pages: 331-339
Publication date: Mar 1997
Peer-reviewed: Yes

Publication information

Journal: Journal of Chemical Technology and Biotechnology
Volume: 68
Issue number: 3
ISSN (Print): 0268-2575
Original language: English
ASJC Scopus subject areas: Biotechnology, Chemical Engineering(all), Bioengineering, Chemistry(all)
Keywords: Anaerobic treatment, Food industry, Granular sludge, Start-up, Thermophilic, Vegetable processing wastewater

Bibliographical note

Contribution: organisation=bio,FACT1=1

Source: researchoutputwizard
Source ID: 30520

Research output: Contribution to journalArticleScientificpeer-review

Biokalvojen rakenteen ja toiminnan simulointi tuo uutta tietoa rasvoista

The article discusses the importance of lipid membranes in biological systems and the use of molecular dynamics simulations to explore their structure and function. Results from a recent study on the effects of polyunsaturation on a phospholipid membrane are presented [Biophys. J. 73 (1997) 2907].

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: University of Oulu
Contributors: Hyvönen, M. T., Rantala, T. T., Ala-Korpela, M.
Number of pages: 4
Pages: 222-225
Publication date: 1999
Peer-reviewed: Yes

Publication information

Journal: Kemia - Kemi
Volume: 26
Issue number: 3
ISSN (Print): 0355-1628
Ratings: 
  • Scopus rating (1999): SJR 0.129 SNIP 0.113
Original language: Finnish
ASJC Scopus subject areas: Chemical Engineering(all)
Source: Scopus
Source ID: 0043139016

Research output: Contribution to journalArticleScientificpeer-review

Anaerobically digested poultry slaughterhouse wastes as fertiliser in agriculture

Chemical and physical analysis, 27-d plant growth assays with carrot (Daucus carota) and Chinese cabbage (Brassica campestris var. chinensis), and 5-d phytotoxicity assays with Chinese cabbage and perennial ryegrass (Lolium perenne) were used to investigate the suitability of anaerobically digested poultry slaughterhouse waste for fertiliser in agriculture and the effect of aerobic post-treatment on the properties of the digested material.The digested material appeared to be rich in nitrogen. In 27-d assays with digested material as nitrogen source, carrots grew almost as well as those fertilised with a commercial mineral fertiliser used as reference, whereas, the growth of Chinese cabbage was inhibited. In further 5-d phytotoxicity assays, the digested material inhibited the germination and root growth of ryegrass and Chinese cabbage, apparently because of organic acids present in it. Aerobic post-treatment of the material reduced its phytotoxicity but, probably due to the volatilisation of ammonia, resulted in loss of nitrogen.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: University of Jyväskylä, Jyväskylän yliopisto
Contributors: Salminen, E., Rintala, J., Härkönen, J., Kuitunen, M., Högmander, H., Oikari, A.
Number of pages: 8
Pages: 81-88
Publication date: 2001
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 78
Issue number: 1
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2001): SJR 0.537 SNIP 1.208
Original language: English
ASJC Scopus subject areas: Agronomy and Crop Science, Food Science, Process Chemistry and Technology, Applied Microbiology and Biotechnology
Keywords: Aerobic post-treatment, Ammonia, Anaerobically digested material, Organic acids, Phytotoxicity assays, Plant growth assays, Poultry slaughterhouse waste
Source: Scopus
Source ID: 0035142679

Research output: Contribution to journalArticleScientificpeer-review

Biological treatment of pulp and paper mill process and wastewaters under thermophilic conditions - A review

The pulp and paper industry generates high-temperature process and wastewaters, which are normally cooled down to about 40°C or less before external biological treatment. So far, treatment at high temperature has rarely been employed in the pulp and paper industry or other industrial wastewater treatment. High temperature is generally considered to suppress the performance of activated sludge and other processes. In this paper, we review some theories and recent findings from laboratory and pilot studies on biological treatment at high temperature. Experimental studies clearly indicate that biological (anaerobic, aerobic, and anaerobic-aerobic) treatment at high temperature (50-60°C) is feasible. The thermophilic process has been shown to be stable over long periods of operation, and the process removal efficiency and loading rates are comparable to, if not higher than, those achieved in the mesophilic process. Furthermore, the thermophilic process can be readily started with sludge from a mesophilic process. Biological treatment at high temperature is thus workable and may well obviate the need to cool wastewater altogether. Further studies and full-scale implementation will disclose in detail the effects of high temperature on loading potential and excess sludge production.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Jyväskylän yliopisto, Department of Biological Science
Contributors: Suvilampi, J., Lepistö, R., Rintala, J.
Number of pages: 6
Pages: 320-325
Publication date: 2001
Peer-reviewed: Yes

Publication information

Journal: Paperi ja puu
Volume: 83
Issue number: 4
ISSN (Print): 0031-1243
Ratings: 
  • Scopus rating (2001): SJR 0.32 SNIP 0.583
Original language: English
ASJC Scopus subject areas: Chemical Engineering (miscellaneous), Materials Science (miscellaneous)
Keywords: Aerobic, Anaerobic, High temperature, Pulp and paper industry wastewaters, Thermophilic treatment
Source: Scopus
Source ID: 0034982577

Research output: Contribution to journalArticleScientificpeer-review

A simulation case study of production planning and control in printed wiring board manufacturing

Production planning and control in printed wiring board (PWB) manufacturing is becoming more difficult as PWB's technology is developing and the production routings become more complex. Simultaneously, the strategic importance of delivery accuracy, short delivery times, and production flexibility is increasing with the highly fluctuating demand and short product life cycles of end products. New principles, that minimize throughput time while guaranteering excellent customer service and adequate capacity utilization, are needed for production planning and control. Simulation is needed in order to develop the new principles and test their superiority. This paper presents an ongoing simulation product that aims at developing the production planning and control of a PWB manufacturer. In the project, a discrete event simulation model is built of a pilot case factory. The model is used for comparing the effect of scheduling, queuing rules, buffer policies, and lot sizes on customer service and cost efficiency.

General information

Publication status: Published
MoE publication type: Not Eligible
Organisations: Industrial Engineering and Management, Aalto University, TAI Research Centre
Contributors: Korhonen, H. M. E., Heikkilä, J., Törnwall, J. M.
Number of pages: 4
Pages: 844-847
Publication date: 1 Dec 2001
Peer-reviewed: Yes

Publication information

Journal: Winter Simulation Conference Proceedings
Volume: 2
ISSN (Print): 0275-0708
Ratings: 
  • Scopus rating (2001): SJR 0.377
Original language: English
ASJC Scopus subject areas: Chemical Health and Safety, Software, Safety, Risk, Reliability and Quality, Applied Mathematics, Modelling and Simulation
Source: Scopus
Source ID: 0035708229

Research output: Contribution to journalConference articleScientificpeer-review

Anaerobic digestion of organic solid poultry slaughterhouse waste - A review

This work reviews the potential of anaerobic digestion for material recovery and energy production from poultry slaughtering by-products and wastes. First, we describe and quantify organic solid by-products and wastes produced in poultry farming and poultry slaughterhouses and discuss their recovery and disposal options. Then we review certain fundamental aspects of anaerobic digestion considered important for the digestion of solid slaughterhouse wastes. Finally, we present an overview of the future potential and current experience of the anaerobic digestion treatment of these materials.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: University of Jyväskylä, Jyväskylän yliopisto
Contributors: Salminen, E., Rintala, J.
Number of pages: 14
Pages: 13-26
Publication date: 2002
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 83
Issue number: 1
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2002): SJR 0.868 SNIP 1.278
Original language: English
ASJC Scopus subject areas: Agronomy and Crop Science, Food Science, Process Chemistry and Technology, Applied Microbiology and Biotechnology
Keywords: Ammonia, Anaerobic digestion, Inhibition, Long-chain fatty acids, Nutrients recovery, Renewable energy, Solid poultry slaughterhouse waste
Source: Scopus
Source ID: 0036158732

Research output: Contribution to journalArticleScientificpeer-review

Modeling of anaerobic degradation of solid slaughterhouse waste: Inhibition effects of long-chain fatty acids or ammonia

The anaerobic bioconversion of solid poultry slaughterhouse wastes was kinetically investigated. The modified version of <METHANE> simulation model was applied for description of experimental data in mesophilic laboratory digester and assays. Additionally, stages of formation and consumption of long chain fatty acids (LCFA) were included in the model. Batch data on volatile solids, ammonium, acetate, butyrate, propionate, LCFA concentrations, pH level, cumulative volume, and methane partial pressure were used for model calibration. As a reference, the model was used to describe digestion of solid sorted household waste. Simulation results showed that an inhibition of polymer hydrolysis by volatile fatty acids and acetogenesis by NH3 or LCFA could be responsible for the complex system dynamics during degradation of lipid- and protein-rich wastes.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Russian Academy of Sciences, University of Jyväskylä, Jyväskylän yliopisto
Contributors: Lokshina, L. Y., Vavilin, V. A., Salminen, E., Rintala, J.
Number of pages: 18
Pages: 15-32
Publication date: Apr 2003
Peer-reviewed: Yes

Publication information

Journal: Applied Biochemistry and Biotechnology
Volume: 109
Issue number: 1-3
ISSN (Print): 0273-2289
Ratings: 
  • Scopus rating (2003): SJR 0.444 SNIP 0.695
Original language: English
ASJC Scopus subject areas: Biochemistry, Genetics and Molecular Biology(all), Biochemistry, Biotechnology, Bioengineering
Keywords: Ammonia, Anaerobic digestion, Inhibition, Long-chain fatty acids, Model, Poultry slaughterhouse waste, Sorted solid household waste
Source: Scopus
Source ID: 0038459271

Research output: Contribution to journalArticleScientificpeer-review

Comparison of laboratory-scale thermophilic biofilm and activated sludge processes integrated with a mesophilic activated sludge process

A combined thermophilic-mesophilic wastewater treatment was studied using a laboratory-scale thermophilic activated sludge process (ASP) followed by mesophilic ASP or a thermophilic suspended carrier biofilm process (SCBP) followed by mesophilic ASP, both systems treating diluted molasses (dilution factor 1:500 corresponding GF/A-filtered COD (CODfilt) of 1900±190 mgl-1). With hydraulic retention times (HRTs) of 12-18 h the thermophilic ASP and thermophilic SCBP removed 60±13% and 62±7% of CODfilt, respectively, with HRT of 8 h the removals were 48±1% and 69±4%. The sludge volume index (SVI) was notably lower in the thermophilic SCBP (measured from suspended sludge) than in the thermophilic ASP. Under the lowest HRT the mesophilic ASP gave better performance (as SVI, CODfilt, and CODtot removals) after the thermophilic SCBP than after the thermophilic ASP. Measured sludge yields were low (less than 0.1 kg suspended solids (SS) kg CODfilt removed -1) in all processes. Both thermophilic treatments removed 80-85% of soluble COD (CODsol) whereas suspended COD (CODsusp) and colloidal COD (CODcol) were increased. Both mesophilic post-treatments removed all CODcol and most of the CODsusp from the thermophilic effluents. In conclusion, combined thermophilic-mesophilic treatment appeared to be easily operable and produced high effluent quality.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Jyväskylän yliopisto, University of Jyväskylä
Contributors: Suvilampi, J., Lehtomäki, A., Rintala, J.
Number of pages: 8
Pages: 207-214
Publication date: Jul 2003
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 88
Issue number: 3
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2003): SJR 0.942 SNIP 1.673
Original language: English
ASJC Scopus subject areas: Agronomy and Crop Science, Food Science, Process Chemistry and Technology, Applied Microbiology and Biotechnology
Keywords: Activated sludge process, Combined treatment, Mesophilic, Suspended carrier biofilm process, Thermophilic
Source: Scopus
Source ID: 0037411631

Research output: Contribution to journalArticleScientificpeer-review

Modeling solid waste decomposition

The hydrolysis rate coefficients of sorted municipal waste were evaluated from the biochemical methane potential tests using non-linear regression. A distributed mathematical model of anaerobic digestion of rich (food) and lean (non-food) solid wastes with greatly different rates of polymer hydrolysis/acidogenesis was developed to describe the balance between the rates of hydrolysis/acidogenesis and methanogenesis. The model was calibrated using previously published experimental data [Biores. Technol. 52 (1995) 245] obtained upon various initial food waste loadings. Simulations of one- and two-stage digestion systems were carried out. The results showed that initial spatial separation of food waste and inoculum enhances methane production and waste degradation in a one-stage solid-bed digester at high waste loading. A negative effect of vigorously mixing at high waste loading reported in some papers was discussed. It was hypothesized that the initiation methanogenic centers developing in time and expanding in space under minimal mixing conditions might be a key factor for efficient anaerobic conversion of solid waste into methane.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Russian Academy of Sciences, University of Jyväskylä, Jyväskylän yliopisto
Contributors: Vavilin, V. A., Lokshina, L. Y., Jokela, J. P. Y., Rintala, J. A.
Number of pages: 13
Pages: 69-81
Publication date: Aug 2004
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 94
Issue number: 1
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2004): SJR 1.19 SNIP 1.658
Original language: English
ASJC Scopus subject areas: Agronomy and Crop Science, Food Science, Process Chemistry and Technology, Applied Microbiology and Biotechnology
Keywords: Distributed mathematical model, Food waste, Hydrolysis kinetics, Initiation methanogenic centers, One- and two-stage anaerobic digestion, Solids biodegradation
Source: Scopus
Source ID: 1842663304

Research output: Contribution to journalArticleScientificpeer-review

Hydrolysis rates, methane production and nitrogen solubilisation of grey waste components during anaerobic degradation

Municipal grey waste (i.e. the remaining fraction in municipal waste management systems in which putrescibles (biowaste) and other recyclables (paper, metals, glass) are source-segregated) was manually sorted into six main fractions on the basis of composition and also separated by sieving (100 mm mesh size) into two fractions, oversized and undersized, respectively. In practice, in waste management plant the oversized fraction is (or will be) used to produce refuse-derived fuel and the undersized landfilled after biological stabilisation. The methane yields and nitrogen solubilisation of the grey waste and the different fractions (all studied samples were first milled to 5 mm particle samples) were determined in a 237-day methane production batch assay and in a water elution test, respectively. The grey waste was found to contained remnants of putrescibles and also a high amount of other biodegradable waste, including packaging, cartons and cardboard, newsprint, textiles and diapers. These waste fractions comprised 41%-w/w of the grey waste and produced 40-210 m3 methane (total solids (TS))-1 and less than 0.01 gNH4-NkgTS-1 added except diapers which produced 9.8 gNH4-N kgTS-1 added in the batch assays. In the case of the two sieved fractions and on mass bases, most of the methane originated from the oversized fraction, whereas most of the NH4-N was solublised from the undersized fraction. The first-order kinetic model described rather well the degradation of each grey waste fraction and component, showing the different components to be in the range 0.021-0.058 d-1, which was around one-sixth of the values reported for the source-segregated putrescible fraction of MSW.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: University of Jyväskylä, Jyväskylän yliopisto, Russian Academy of Sciences
Contributors: Jokela, J. P. Y., Vavilin, V. A., Rintala, J. A.
Number of pages: 8
Pages: 501-508
Publication date: Mar 2005
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 96
Issue number: 4
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2005): SJR 1.278 SNIP 1.99
Original language: English
ASJC Scopus subject areas: Agronomy and Crop Science, Food Science, Process Chemistry and Technology, Applied Microbiology and Biotechnology
Keywords: Anaerobic degradation, Components, Grey waste, Hydrolysis rate, Landfill, Methane, Municipal solid waste, Nitrogen, Solubilisation, Source-segregation
Source: Scopus
Source ID: 7544250470

Research output: Contribution to journalArticleScientificpeer-review

Anaerobic on-site treatment of kitchen waste in combination with black water in UASB-septic tanks at low temperatures

Anaerobic on-site treatment of a mixture of black water and kitchen waste (BWKW) was studied using two-phased upflow anaerobic sludge blanket (UASB) septic tanks at the low temperatures of 20 and 10 °C. Black water (BW) was also treated alone as reference. The two-phased UASB-septic tanks removed over 95% of total suspended solids (TSS) and 90% of total chemical oxygen demand (CODt) from both BWKW (effluent CODt 171-199 mg/l) and BW (effluent CODt 92-100 mg/l). Also, little dissolved COD (CODdis) was left in the final effluents (BW 48-70 mg/l; BWKW 110-113 mg/l). Part of total nitrogen (Ntot) was removed (BW 18% and BWKW 40%) and especially at 20 °C ammonification was efficient. A two-phased process was required to obtain the high removals with BWKW at 10 °C, while with BW a single-phased process may have sufficed even at 10 °C. BWKW also produced more methane than BW alone. Sludge in phases 1 of BW and BWKW treatment was not completely stabilised after 198 d of operation.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Jyväskylän yliopisto, University of Jyväskylä
Contributors: Luostarinen, S., Rintala, J.
Number of pages: 7
Pages: 1734-1740
Publication date: Jul 2007
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 98
Issue number: 9
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2007): SJR 1.403 SNIP 2.411
Original language: English
ASJC Scopus subject areas: Agronomy and Crop Science, Food Science, Process Chemistry and Technology, Applied Microbiology and Biotechnology
Keywords: Anaerobic wastewater treatment, Black water, Kitchen waste, Low temperature, UASB-septic tank
Source: Scopus
Source ID: 33846677724

Research output: Contribution to journalArticleScientificpeer-review

Statistical modeling of water vapor transmission rates for extrusion-coated papers

The testing of water vapor transmission rates (WVTR) for extrusion-coated papers can be a time-consuming task for laboratories. This study introduces a prediction model that provides an effective and helpful option to laboratory measurements. In practice, the WVTR of an extrusion-coated paper is affected by three main factors: coating weight (or squared mass) of the polymer concerned, the temperature and moisture content of the immediate surroundings. The prediction model determines mathematical connections between the WVTR and these variables covering the detected region of experimental WVTR results with a continuous estimation. By using mixing ratio as a variable of humidity, the model was found to provide accurate estimation across the field of experiments. As a result of this study, a practical computer program, which predicts the WVTR of a multilayer extrusion-coated paper as a function of user-defined temperature and relative humidity values and the layer structure of the coating, was developed. APPLICATION STATEMENT: This work shows how WVTR of a multilayer extrusion-coated paper can be estimated with the help of a statistical prediction model.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Energy and Process Engineering, Department of Materials Science
Contributors: Lahtinen, K., Kuusipalo, J.
Publication date: 2008

Host publication information

Title of host publication: TAPPI 2008 PLACE Conference: Innovations in Flexible Consumer Packaging
ASJC Scopus subject areas: Chemical Engineering(all), Chemistry(all), Mechanical Engineering, Media Technology, Materials Science(all)
Source: Scopus
Source ID: 77950684840

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Effects of solid-liquid separation on recovering residual methane and nitrogen from digested dairy cow manure

The feasibility of optimizing methane and nitrogen recovery of samples obtained from farm biogas digester (35 °C) and post-storage tank (where digested material is stored for 9-12 months) was studied by separating the materials into different fractions using 2, 1, 0.5 and 0.25 mm sieves. Mass-balances revealed that digested material mainly consists of <0.25 mm (60-69%) and >2 mm (18-27%) fractions, while fractions between 2 and 0.25 mm made the rest. Incubation of solid fractions >0.25 mm of digester material at 35 °C resulted in specific methane yields of 0.060-0.085 m3 kg-1 volatile solids (VS) during initial 30-50 d and 0.16-0.18 m3 kg-1 VS at the end of 340 d incubation. Similarly, fractions >0.25 mm of post-storage tank material produced 0.055-0.092 m3 kg-1 VS and 0.13-0.16 m3 kg-1 VS of methane after 30-50 d and after 250 d, respectively. Methane yields for fractions <0.25 mm of post-storage tank was 0.03 m3 kg-1 VS after 30-50 d and 0.05 m3 kg-1 VS after 250 d compared to 0.20 m3 kg-1 VS and 0.41 m3 kg-1 VS, respectively for the same fraction of digester material. Separation of digested cow manure into solids and liquid fractions to recover methane may be feasible only for post-storage tank material and not for digester material. Nitrogen management would not be feasible with neither material as total nitrogen and ammonium-nitrogen concentrations were equally distributed among the segregated fractions.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Jyväskylän yliopisto, University of Jyväskylä
Contributors: Kaparaju, P. L. N., Rintala, J. A.
Number of pages: 8
Pages: 120-127
Publication date: Jan 2008
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 99
Issue number: 1
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2008): SJR 1.736 SNIP 2.724
Original language: English
ASJC Scopus subject areas: Agronomy and Crop Science, Food Science, Process Chemistry and Technology, Applied Microbiology and Biotechnology, Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Anaerobic digestion, Digested material, Farm-scale digester, Fractionation, Methane, Post-storage tank
Source: Scopus
Source ID: 34848884581

Research output: Contribution to journalArticleScientificpeer-review

Anaerobic digestion of grass silage in batch leach bed processes for methane production

Anaerobic digestion of grass silage in batch leach bed reactors, with and without a second stage upflow anaerobic sludge blanket (UASB) reactor, was evaluated. Sixty six percent of the methane potential in grass was obtained within the 55 days solids retention time in the leach bed-UASB process without pH adjustment, whereas in the one-stage leach bed process 20% of the methane potential in grass was extracted. In two-stage operation, adjustment of the pH of influent to the leach bed reactor to 6 with HCl led to inhibition of both hydrolysis/acidogenesis and methanogenesis. In the leach bed-UASB process 39% of the carbohydrates and 58% of the acid soluble lignin were solubilised within the 49 days of operation, whereas Klason lignin was most recalcitrant. The methane potential of the digestates varied from 0.141 to 0.204 m3 CH4 kg-1 added volatile solids.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Jyväskylän yliopisto, University of Jyväskylä
Contributors: Lehtomäki, A., Huttunen, S., Lehtinen, T. M., Rintala, J. A.
Number of pages: 12
Pages: 3267-3278
Publication date: May 2008
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 99
Issue number: 8
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2008): SJR 1.736 SNIP 2.724
Original language: English
ASJC Scopus subject areas: Agronomy and Crop Science, Food Science, Process Chemistry and Technology, Applied Microbiology and Biotechnology
Keywords: Anaerobic digestion, Energy crop, Leach bed, Methane production, UASB
Source: Scopus
Source ID: 38849145183

Research output: Contribution to journalArticleScientificpeer-review

Leachate and gaseous emissions from initial phases of landfilling mechanically and mechanically-biologically treated municipal solid waste residuals

In this study, the behaviour, and leachate and gaseous emissions during the initial phases of landfilling mechanically (M) and mechanically-biologically (MB) treated municipal solid waste residuals in northern climatic conditions was compared using two landfill lysimeters (112 m3). The results demonstrate that the strong acid phase of M residuals degradation lasts at least 2 years, while in the MB residuals the acid phase lasts only a few months. The SCOD and NH4-N concentrations varied 20-100 g/l and 600-1800 mg/l in M leachate and 1-4 g/l and 100-400 mg/l in MB leachate, respectively. The leaching of SCOD was approximately 40-fold (24.2 and 0.6 kg/t TS) and leaching of NH4-N approximately 5-fold (356 and 60 g/t TS) from the M than MB residuals; thus the effect of biological stabilisation was more marked on the leaching of SCOD than of NH4-N. Moreover gas (methane, carbon dioxide and nitrous oxide) emissions were several-fold higher from the M than MB residuals.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Jyväskylän yliopisto, Matti Ettala Ltd., University of Jyväskylä
Contributors: Sormunen, K., Einola, J., Ettala, M., Rintala, J.
Number of pages: 11
Pages: 2399-2409
Publication date: May 2008
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 99
Issue number: 7
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2008): SJR 1.736 SNIP 2.724
Original language: English
ASJC Scopus subject areas: Agronomy and Crop Science, Food Science, Process Chemistry and Technology, Applied Microbiology and Biotechnology
Keywords: Landfill, Mechanical-biological, Methane, Nitrogen, Organic matter
Source: Scopus
Source ID: 38849165441

Research output: Contribution to journalArticleScientificpeer-review

Group-specific quantification of methanotrophs in landfill gas-purged laboratory biofilters by tyramide signal amplification-fluorescence in situ hybridization

The aim of this study was to quantitatively analyse methanotrophs in two laboratory landfill biofilters at different biofilter depths and at temperatures which mimicked the boreal climatic conditions. Both biofilters were dominated by type I methanotrophs. The biofilter depth profiles showed that type I methanotrophs occurred in the upper layer, where relatively high O2 and low CH4 concentrations were present, whereas type II methanotrophs were mostly distributed in the zone with high CH4 and low O2 concentrations. The number of type I methanotrophic cells declined when the temperature was raised from 15 °C to 23 °C, but increased when lowered to 5 °C. A slight decrease in type II methanotrophs was also observed when the temperature was raised from 15 °C to 23 °C, whereas cell numbers remained constant when lowered to 5 °C. The results indicated that low temperature conditions favored both type I and type II methanotrophs in the biofilters.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Jyväskylän yliopisto, University of Tampere Institute of Medical Technology, University of Jyväskylä
Contributors: Wang, H., Einola, J., Heinonen, M., Kulomaa, M., Rintala, J.
Number of pages: 8
Pages: 6426-6433
Publication date: Sep 2008
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 99
Issue number: 14
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2008): SJR 1.736 SNIP 2.724
Original language: English
ASJC Scopus subject areas: Agronomy and Crop Science, Food Science, Process Chemistry and Technology, Applied Microbiology and Biotechnology
Keywords: Biofilter, Landfill cover soil, Methane oxidation, Methanotrophs, Tyramide signal amplification-fluorescence in situ hybridization
Source: Scopus
Source ID: 43849105101

Research output: Contribution to journalArticleScientificpeer-review

Effects of storage on characteristics and hygienic quality of digestates from four co-digestion concepts of manure and biowaste

This study evaluated the effects of storage in northern winter conditions (5 °C) on the characteristics and nutrients separation of digestates from co-digestion of manure and biowaste as well as the hygienic quality of the digestates after digestion and storage. During 3-11 months' storage average nitrogen losses and reductions of total solids (TS) and volatile solids (VS) were 0-15%. With some exceptions, soluble chemical oxygen demand (SCOD) had increased slightly (from ∼6.5 to ∼7.5 g/l) after 3 months' storage, while after 9-11 months' it had decreased from 8.3-11 to 5.6-8.4 g/l. The concentrations of Ptot and PO4-P in the separated liquid fractions decreased 40-57% after 3 months' storage and 71-91% after 9 months' storage compared to the initial concentrations. The methane potential losses during 9-11 months' storage corresponded 0-10% of the total methane potential without storage. The hygienic quality of the digestates from the 55 °C reactor and during storage fulfilled the Animal By-Products Regulation (ABPR) demands while the 35 °C digestate contained 0-105 cfu/g of indicator bacteria (faecal coliforms, enterobacteria, enterococcus) and >10 cfu/g of spiked salmonella, which amounts decreased slowly during storage. Sulphite reducing clostridia was not affected by either digestion or storage.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Jyväskylän yliopisto, University of Jyväskylä
Contributors: Paavola, T., Rintala, J.
Number of pages: 10
Pages: 7041-7050
Publication date: Oct 2008
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 99
Issue number: 15
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2008): SJR 1.736 SNIP 2.724
Original language: English
ASJC Scopus subject areas: Agronomy and Crop Science, Food Science, Process Chemistry and Technology, Applied Microbiology and Biotechnology, Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Biowaste, Digestate, Hygienic quality, Manure, Solid/liquid separation
Source: Scopus
Source ID: 44449089925

Research output: Contribution to journalArticleScientificpeer-review

Storing energy crops for methane production: Effects of solids content and biological additive

The effect of storage on chemical characteristics and CH4 yield (taking into account loss of VS during storage) of a mixture of grasses and ryegrass, ensiled as such (low solids content) and after drying (medium and high solids) with and without biological additive, were studied in field and laboratory trials. Up to 87% and 98% of CH4 yield was preserved with low solids grass (initial TS 15.6%) and high solids ryegrass (initial TS 30.4%), respectively, after storage for 6 months, while under suboptimal conditions at most 37% and 52% of CH4 yield were lost. Loss in CH4 yield was mainly due to VS loss, presumably caused by secondary fermentation as also suggested by increasing pH during storage. Biological additive did not assist in preserving the CH4 yield.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Jyväskylän yliopisto, University of Jyväskylä
Contributors: Pakarinen, O., Lehtomäki, A., Rissanen, S., Rintala, J.
Number of pages: 9
Pages: 7074-7082
Publication date: Oct 2008
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 99
Issue number: 15
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2008): SJR 1.736 SNIP 2.724
Original language: English
ASJC Scopus subject areas: Agronomy and Crop Science, Food Science, Process Chemistry and Technology, Applied Microbiology and Biotechnology, Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Anaerobic digestion, Biogas, Energy crop, Grass, Storage
Source: Scopus
Source ID: 44449146372

Research output: Contribution to journalArticleScientificpeer-review

The effects of corona and flame treatment: Part 2. PE-HD and PP coated papers

The most important function of a packaging material is to shield the product inside the package. Extrusion coated papers and paperboards are generally used in various consumer packages like food, medical and cosmetic packages. Extrusion coatings give a barrier against water, water vapour, aroma, grease, oxygen, etc. In addition to barrier properties, heat sealability and printability are important properties in packaging applications. From the point of view of printing, the dense and impervious structure of extrusion coatings is challenging: printing inks and toners do not penetrate into the coatings. The durability of the printed image is significant, because the image must withstand various converting operations when the package is constructed. The most common method for obtaining good ink or toner adhesion is to oxidise the surface. Surface treatments are used to change the chemical composition, increase surface energy, modify surface morphology and topography, or remove contaminants and weak boundary layers. Two widely used methods are corona discharge treatment and flame treatment. These processes generally cause physical and chemical changes in a thin surface layer without affecting the bulk properties. Treatments will increase surface energy and also provide polar molecular groups necessary for good bonds between ink/toner and polymer molecules. In addition to printability, surface treatments also affect the sealing properties, i.e. initial heat sealing temperature, initial hot tack temperature, sealing window and seal strength of extrusion coatings. Both the sealability of packaging material and the tightness of the seal are critical points in the manufacturing process of packages and of the final package. The printability must be obtained without losing the sealability properties. In the first part of this research (TAPPI European PLACE 2007), surface energy, printability and sealability of low density polyethylene (PE-LD) coated paperboard after flame and corona treatments were studied. In this second part of the study, the research is extended to other polyolefins, i.e. high-density polyethylene (PE-HD) and polypropylene (PP). The surface chemistry is evaluated with contact angle measurements and X-ray photoelectron spectroscopy (XPS) measurements. Scanning electron microscopy (SEM) and optical profilometry are used to study the topographical and morphological changes on the surfaces. Furthermore, the heat sealing and hot tack properties, and water vapour barrier properties of the extrusion coatings are evaluated. The aim of this study is also to evaluate the printability of the extrusion coatings and to map out the role of surface modification in print quality formation. This study has concentrated on digital printing, particularly on the dry toner-based electrophotographic printing process. Flame treatment decreases the contact angle of water on PE-LD, PE-HD and PP coated papers more than corona treatment, but the lowest contact angle is obtained when the treatments are used simultaneously (i.e. co-effect of the treatments). Flame treatment deteriorates the sealability properties of PE-LD coated paper, whereas corona treatment improves sealability for example by decreasing the minimum heat sealing temperature. The sealability properties of PE-HD and PP coated papers are improved not only by corona treatment, but also by flame treatment. Flame treatment significantly improves the water vapour barrier of PEs. Where printability is concerned, it can be noticed that all the treatments improve rub-off resistance with PEs. With PE-LD flame is the most effective, and with PE-HD corona. With PP, the co-treatment gives the best result. Morphological changes in micro- and nano- scale were most observed on the flame treated PE-LD surface, whereas the electret phenomenon was observed on PE-LD, PE-HD and PP surfaces only after corona treatment.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Materials Science, Paper Converting and Packaging Technology, Stora Enso
Contributors: Lahti, J., Tuominen, M., Penttinen, T., Räsänen, J. P., Kuusipalo, J.
Number of pages: 37
Pages: 278-314
Publication date: 2009

Host publication information

Title of host publication: TAPPI Press - 12th European PLACE Conference 2009
Volume: 1
ISBN (Print): 9781615679850
ASJC Scopus subject areas: Media Technology, Chemical Engineering(all), Chemistry(all), Mechanical Engineering, Materials Science(all)
Source: Scopus
Source ID: 77952354412

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Impact of crop species on bacterial community structure during anaerobic co-digestion of crops and cow manure

The bacterial communities in three continuously stirred tank reactors co-digesting cow manure with grass silage, oat straw, and sugar beet tops, respectively, were investigated by 16S rRNA gene-based fingerprints and clone libraries. The analyses revealed both clearly distinct and similar phylotypes in the bacterial communities between the reactors. The major groups represented in the three reactors were Clostridia, unclassified Bacteria, and Bacteroidetes. Phylotypes affiliated with Bacilli or Deltaproteobacteria were unique to the sugar beet and straw reactor, respectively. Unclassified Bacteria dominated in sugar beet reactor while in the straw and grass reactor Clostridia was the dominant group. An increase in organic loading rate from 2 to 3 kg volatile solids m-3 d-1 resulted in larger changes in the bacterial community in the straw compared to grass reactor. The study shed more light on the evolution of bacterial community during anaerobic co-digestion of different crops and manure to methane. © 2008 Elsevier Ltd. All rights reserved.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Tampere University of Technology, Jyväskylän yliopisto, Jyväskylä Innovation Ltd., University of Jyväskylä
Contributors: Wang, H., Lehtomäki, A., Tolvanen, K., Puhakka, J., Rintala, J.
Number of pages: 5
Pages: 2311-2315
Publication date: Apr 2009
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 100
Issue number: 7
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2009): SJR 1.915 SNIP 2.235
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Anaerobic digestion, Bacterial community structure, Continuously stirred tank reactor, Denature gradient gel electrophoresis, Terminal restriction fragment length polymorphism

Bibliographical note

poistettu tupla r=235<br/>Contribution: organisation=keb bio,FACT1=1

Source: researchoutputwizard
Source ID: 11706

Research output: Contribution to journalArticleScientificpeer-review

Biogas production from boreal herbaceous grasses - Specific methane yield and methane yield per hectare

The objective of this study was to determine the specific methane yields of four grass species (cocksfoot, tall fescue, reed canary grass and timothy) cultivated under boreal conditions as well as how harvesting time and year of cultivation affects the specific methane yields per ha. The specific methane yields of all grasses and all harvests varied from 253 to 394 Nl CH4/kg volatile solids (VS) added. The average specific methane yield of the 1st harvest of all grasses was higher than the 2nd harvests. In this study the methane and energy yields from different harvest years were ranged from 1200 to 3600 Nm3 CH4/ha/a, corresponding from 12 to 36 MWhCH4/ha/a. The methane yield per hectare of the 1st harvest was always higher than that of the 2nd harvest per hectare because of the higher dry matter yield and specific methane yield. High biomass yield per hectare, good digestibility and regrowth ability after harvesting are important factors when choosing grass species for biogas production. If 30% of fallow and the second harvest of grassland were cultivated grasses and harvested for biogas production in Finland, the energy produced could be 4.9 TWhCH4.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Jyväskylän yliopisto, University of Jyväskylä
Contributors: Seppälä, M., Paavola, T., Lehtomäki, A., Rintala, J.
Number of pages: 7
Pages: 2952-2958
Publication date: Jun 2009
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 100
Issue number: 12
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2009): SJR 1.915 SNIP 2.235
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Biogas production, Grass, Harvest time, Specific methane yield
Source: Scopus
Source ID: 62649158890

Research output: Contribution to journalArticleScientificpeer-review

On entropy-based molecular descriptors: Statistical analysis of real and synthetic chemical structures

This paper presents an analysis of entropy-based molecular descriptors. Specifically, we use real chemical structures, as well as synthetic isomeric structures, and investigate properties of and among descriptors with respect to the used data set by a statistical analysis. Our numerical results provide evidence that synthetic chemical structures are notably different to real chemical structures and, hence, should not be used to investigate molecular descriptors. Instead, an analysis based on real chemical structures is favorable. Further, we find strong hints that molecular descriptors can be partitioned into distinct classes capturing complementary information.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: TU Vienna, Technical University Darmstadt, Computational Biology and Machine Learning, School of Medicine
Contributors: Dehmer, M., Varmuza, K., Borgert, S., Emmert-Streib, F.
Number of pages: 9
Pages: 1655-1663
Publication date: 27 Jul 2009
Peer-reviewed: Yes

Publication information

Journal: Journal of Chemical Information and Modeling
Volume: 49
Issue number: 7
ISSN (Print): 1549-9596
Ratings: 
  • Scopus rating (2009): SJR 1.039 SNIP 1.219
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all), Chemistry(all), Computer Science Applications, Library and Information Sciences
Source: Scopus
Source ID: 68149167631

Research output: Contribution to journalArticleScientificpeer-review

Surface science analysis and surface modification methods for biomaterials research

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Research group: Surface Science, Department of Physics, Department of Biomedical Engineering, University of Tampere Institute of Medical Technology, Department of Biomedical Engineering
Contributors: Kanninen, L., Jokinen, N., Lahtonen, K., Jussila, P., Ali-Löytty, H., Hirsimäki, M., Leppiniemi, J., Hytönen, V., Kulomaa, M., Ahola, N., Paakinaho, K., Kellomäki, M., Valden, M.
Number of pages: 1
Pages: 133
Publication date: 1 Jan 2010
Peer-reviewed: Yes

Publication information

Journal: European Cells and Materials
Volume: 20
Issue number: SUPPL. 3
ISSN (Print): 1473-2262
Ratings: 
  • Scopus rating (2010): SJR 0.192 SNIP 0.193
Original language: English
ASJC Scopus subject areas: Bioengineering, Biochemistry, Biomaterials, Biomedical Engineering, Cell Biology
Source: Scopus
Source ID: 84860892200

Research output: Contribution to journalArticleScientificpeer-review

Effect of micro-aeration and leachate replacement on COD solubilization and VFA production during mono-digestion of grass-silage in one-stage leach-bed reactors

The effect of micro-aeration and leachate replacement with fresh water on chemical oxygen demand (COD) solubilization and volatile fatty acid (VFA) production during the mono-digestion of grass-silage in one-stage leach-bed reactors (LBRs) was investigated in four LBRs, L0 (control), L1, L2 and L3 in batch mode at 35 ± 1 °C for 57 days. Results showed that leachate replacement without pH adjustment (L3) resulted in 2.7 and 1.3 times more SCOD in the leachate compared to control (L0) or leachate replacement with initial pH adjustment (L1), respectively. Micro-aeration at flow rate of 1 L min-1 (2.5 L of air) in L2 resulted in 4-fold increase in VFA production (from 2.2 to 9 g L-1) without any significant increase in cumulative SCOD in the leachate. Increasing the air flow rate to 4 L min-1 (24 L of air) in L2 resulted in a decrease in SCOD extraction. Leachate replacement without pH adjustment (L3) resulted in higher (mean) specific SCOD production (0.51 g SCOD g-1 VSadded) than control (L0, 0.34 g SCOD g-1 VSadded), leachate replacement with initial pH adjustment (L1, 0.33 g SCOD g-1 VSadded) or micro-aeration (L2, 0.32 g SCOD g-1 VSadded). These results suggest that the challenge of hydrolysis during anaerobic digestion of particulate substrates like grass-silage can be improved by micro-aeration and leachate replacement methods with or without pH adjustment.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Jyväskylän yliopisto, University of Jyväskylä
Contributors: Jagadabhi, P. S., Kaparaju, P., Rintala, J.
Number of pages: 7
Pages: 2818-2824
Publication date: Apr 2010
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 101
Issue number: 8
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2010): SJR 2.089 SNIP 2.348
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Grass-silage, Leach-bed reactor, Leachate replacement, Micro-aeration, Solubilization
Source: Scopus
Source ID: 73749087133

Research output: Contribution to journalArticleScientificpeer-review

Effect of pre-treatments on barrier properties of layers applied by atomic layer deposition onto polymer-coated substrates

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Materials Science, Department of Materials Science, Engineering materials science and solutions (EMASS), VTT Technical Research Centre of Finland
Contributors: Vähä-Nissi, M., Hirvikorpi, T., Sievänen, J., Salo, E., Harlin, A., Johansson, P., Kuusipalo, J.
Number of pages: 1
Pages: 447
Publication date: 2011

Host publication information

Title of host publication: 13th European PLACE Conference 2011
Volume: 1
ISBN (Print): 9781618394392
ASJC Scopus subject areas: Media Technology, Chemical Engineering(all), Chemistry(all), Mechanical Engineering, Materials Science(all)
Source: Scopus
Source ID: 84859608155

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Enrichment polymer layers for detection of volatile vapors by ATR FT-IR

Fourier Transformed Infrared Spectroscopy (FT-IR) is an effective analytical method for the identification of organic compounds be they man made or naturally produced. There is, however, a limitation to what a normal FT-IR can detect if an analyte is in vapor phase or in low concentration. To this end, we have applied enrichment polymer layer systems (EPLS) to an attenuated total reflection (ATR) crystal waveguide to enhance detection capability for the method. These EPLS are comprised of polymers with different functionality along the backbone and provide unique interaction capabilities that can attract volatile chemicals and concentrate them in the evanescence wave region. The thickness of the polymer layers is kept on 30-50nm level. The EPLS were characterized by atomic force microscopy, ellipsometry and FT-IR. The overall goal of this work is to construct a "universal" sensor platform capable of detecting a wide range of volatile organic chemicals via infrared spectroscopy.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Frontier Photonics, Massachusetts Institute of Technology, School of Materials Science and Engineering/COMSET, Clemson University, Department of Materials Science and Engineering, University of Delaware
Contributors: Giammarco, J. M., Zdyrko, B., Hu, J., Agarwal, A., Kimerling, L., Carlie, N., Petit, L., Richardson, K., Luzinov, I.
Publication date: 2011
Peer-reviewed: Yes

Publication information

Journal: ACS National Meeting Book of Abstracts
ISSN (Print): 0065-7727
Ratings: 
  • Scopus rating (2011): SJR 0.101 SNIP 0
Original language: English
ASJC Scopus subject areas: Chemistry(all), Chemical Engineering(all)
Source: Scopus
Source ID: 80051876637

Research output: Contribution to journalArticleScientificpeer-review

Nanoparticle deposition on packaging materials by the liquid flame spray

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Materials Science, Department of Physics, Research area: Aerosol Physics, Department of Software Systems, Engineering materials science and solutions (EMASS), Paper Converting and Packaging Technology, Aerosol Physics Laboratory, Abo Akad Univ, Abo Akademi University, Dept Phys, Center for Functional Materials at Biological Interfaces (FUNMAT)
Contributors: Teisala, H., Tuominen, M., Aromaa, M., Mäkelä, J. M., Stepien, M., Saarinen, J. J., Toivakka, M., Kuusipalo, J.
Number of pages: 2
Publication date: 2011

Host publication information

Title of host publication: 13th European PLACE Conference 2011
Volume: 1
ISBN (Print): 9781618394392
ASJC Scopus subject areas: Media Technology, Chemical Engineering(all), Chemistry(all), Mechanical Engineering, Materials Science(all)
Source: Scopus
Source ID: 84859599609

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Chimeric avidin shows stability against harsh chemical conditions-biochemical analysis and 3D structure

Avidin and its bacterial analog streptavidin have been widely used in applications in life sciences. Recently, we described a highly thermostable engineered avidin, called chimeric avidin, which is a hybrid of avidin and avidin-related protein 4. Here, we report a protocol for pilot-scale production in E. coli and the X-ray structure of chimeric avidin. The ligand-binding properties of chimeric avidin were explored with isothermal titration calorimetry. We found chimeric avidin to be more stable against various harsh organic solvents at elevated temperatures compared to avidin and streptavidin. The properties of chimeric avidin make it a potential tool for new applications in biotechnology. Biotechnol. Bioeng. 2011; 108:481-490.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Multi-scaled biodata analysis and modelling (MultiBAM), University of Tampere Institute of Medical Technology, Hebrew University of Jerusalem
Contributors: Määttä, J. A., Eisenberg-Domovich, Y., Nordlund, H. R., Hayouka, R., Kulomaa, M. S., Livnah, O., Hytönen, V. P.
Number of pages: 10
Pages: 481-490
Publication date: Mar 2011
Peer-reviewed: Yes

Publication information

Journal: Biotechnology and Bioengineering
Volume: 108
Issue number: 3
ISSN (Print): 0006-3592
Ratings: 
  • Scopus rating (2011): CiteScore 7.5 SJR 1.668 SNIP 1.489
Original language: English
ASJC Scopus subject areas: Biotechnology, Bioengineering, Applied Microbiology and Biotechnology
Keywords: Avidin-biotin, Nanobiotechnology, Protein engineering, Thermodynamics, X-ray structure
Source: Scopus
Source ID: 78751523876

Research output: Contribution to journalArticleScientificpeer-review

Osteoconductive properties of poly(96L/4D-lactide)/beta-tricalcium phosphate in long term animal model

The objective of this study was to determine the effect of calcium phosphate mineral content on the bone in-growth at the expense of composite of co-polylactide polymer charged with 2 different ratios of β-TCP granules (10 and 24 w-% of β-TCP). The evaluation was realized in a long term rabbit bone model. After 24, 48 and 76 weeks, the implants were examined by micro CT, scanning electron microscopy (SEM) using backscattered electron (BSE) and light microscopy (polarized and blue light microscopy). No foreign body reaction was detected during the 76 weeks follow-up in any of the test samples. Polymer hydrolysis began at approximately 24 weeks, by 76 weeks, the pure polymer implant had begun to release P(96L/4D)LA particles and show signs of peripheral localized bone resorption. A decrease in the amount of CaP was noticed between 24 and 76 weeks in both 10 wt-% and 24 wt-% β-TCP/P(96L/4D)LA composites. The study showed that the highest bone in-growth was with 24 wt-% β-TCP/P(96L/4D)LA composite. Bone in-growth and mineralization were evident for the composites associated with specific peripheral bone architecture. Fluorescent labelling demonstrated high bone in-growth and remodeling at the interface, while for pure co-polymer no bone remodeling or bone activity was maintained after 48 weeks. The study demonstrated the positive effect of calcium phosphate content into P(96L/4D)LA. This kind of composite is a suitable resorbable osteoconductive matrix, which provides long term stability required for ligament fixation device.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Engineering materials science and solutions (EMASS), PTIB Hôpital Xavier Arnozan, National Veterinary School of Nantes, Conmed Linvatec Biomaterials Ltd.
Contributors: Daculsi, G., Goyenvalle, E., Cognet, R., Aguado, E., Suokas, E. O.
Number of pages: 12
Pages: 3166-3177
Publication date: Apr 2011
Peer-reviewed: Yes

Publication information

Journal: Biomaterials
Volume: 32
Issue number: 12
ISSN (Print): 0142-9612
Ratings: 
  • Scopus rating (2011): CiteScore 11.3 SJR 3.302 SNIP 2.203
Original language: English
ASJC Scopus subject areas: Biomaterials, Bioengineering, Ceramics and Composites, Mechanics of Materials, Biophysics
Keywords: Bone regeneration, Co-polylactide/beta-tricalcium phosphate, Composite, Long term study
Source: Scopus
Source ID: 79951769703

Research output: Contribution to journalArticleScientificpeer-review

Two-stage anaerobic digestion of tomato, cucumber, common reed and grass silage in leach-bed reactors and upflow anaerobic sludge blanket reactors

Anaerobic digestion of tomato, cucumber, common reed and grass silage was studied in four separate two-stage reactor configuration consisting of leach bed reactor (LBR) and upflow anaerobic sludge blanket reactor (UASB). LBR studies showed that COD solubilization for cucumber and grass silage was higher (50%) than tomato (35%) and common reed (15%). Results also showed that 31-39% of initial TKN present in tomato and cucumber was solubilized in the leachates and 47-54% of the solubilized TKN was converted to NH4-N. The corresponding values for common reed and grass silage were 38-50% and 18-36%, respectively. Biomethanation of the leachates in UASB reactors resulted in methane yields of 0.03-0.14m3 CH4 kg-1VSfed for the studied crop materials. Thus, high COD solubilization, high nitrogen mineralization and solubilization rates were feasible during anaerobic digestion of lignocellulosic materials in a two-stage LBR-UASB reactor system.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Urban circular bioeconomy (UrCirBio), Jyväskylän yliopisto, University of Jyväskylä
Contributors: Jagadabhi, P. S., Kaparaju, P., Rintala, J.
Number of pages: 8
Pages: 4726-4733
Publication date: Apr 2011
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 102
Issue number: 7
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2011): CiteScore 7.9 SJR 2.308 SNIP 2.526
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Biogas, Crop materials, Leach bed reactor, Leachate, Two-stage
Source: Scopus
Source ID: 79951945757

Research output: Contribution to journalArticleScientificpeer-review

Hybrid nanoparticle design based on cationized gelatin and the polyanions dextran sulfate and chondroitin sulfate for ocular gene therapy

We describe the development of hybrid nanoparticles composed of cationized gelatin and the polyanions CS and DS for gene therapy in the ocular surface. The physicochemical properties of the nanoparticles that impact their bioperformance, such as average size and zeta potential, can be conveniently modulated by changing the ratio of polymers and the crosslinker. These systems associate plasmid DNA and are able to protect it from DNase I degradation. We corroborate that the introduction of CS or DS in the formulation decreases the in vitro toxicity of the nanoparticles to human corneal cells without compromising the transfection efficiency. These nanoparticles are potential candidates for the development of safer and more effective nanomedicines for ocular therapy. New hybrid nanoparticles composed of cationized gelatin and natural polyanions are developed and characterized. The incorporation of chondroitin sulfate or dextran sulfate in cationized gelatin nanoparticles decreases their toxicity while preserving their transfection efficiency in human corneal cells. These nanoparticles are potential candidates for the development of safer and more effective nanomedicines for ocular therapy.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Integrated Technologies for Tissue Engineering Research (ITTE), University of Santiago de Compostela (USC)
Contributors: Zorzi, G. K., Párraga, J. E., Seijo, B., Sánchez, A.
Number of pages: 9
Pages: 905-913
Publication date: 7 Jul 2011
Peer-reviewed: Yes

Publication information

Journal: MACROMOLECULAR BIOSCIENCE
Volume: 11
Issue number: 7
ISSN (Print): 1616-5187
Ratings: 
  • Scopus rating (2011): CiteScore 5.4 SJR 1.408 SNIP 1.104
Original language: English
ASJC Scopus subject areas: Biotechnology, Bioengineering, Biomaterials, Polymers and Plastics, Materials Chemistry
Keywords: Drug delivery systems, Gelation, Nanoparticles, Nanotechnology
Source: Scopus
Source ID: 79959848036

Research output: Contribution to journalArticleScientificpeer-review

Defined-size DNA triple crossover construct for molecular electronics: Modification, positioning and conductance properties

We present a novel, defined-size, small and rigid DNA template, a so-called B-A-B complex, based on DNA triple crossover motifs (TX tiles), which can be utilized in molecular scale patterning for nanoelectronics, plasmonics and sensing applications. The feasibility of the designed construct is demonstrated by functionalizing the TX tiles with one biotin-triethylene glycol (TEG) and efficiently decorating them with streptavidin, and furthermore by positioning and anchoring single thiol-modified B-A-B complexes to certain locations on a chip via dielectrophoretic trapping. Finally, we characterize the conductance properties of the non-functionalized construct, first by measuring DC conductivity and second by utilizing AC impedance spectroscopy in order to describe the conductivity mechanism of a single B-A-B complex using a detailed equivalent circuit model. This analysis also reveals further information about the conductivity of DNA structures in general.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Multi-scaled biodata analysis and modelling (MultiBAM), Jyväskylän yliopisto, Adult Stem Cells, School of Management (JKK)
Contributors: Linko, V., Leppiniemi, J., Paasonen, S. T., Hytönen, V. P., Jussi Toppari, J.
Publication date: 8 Jul 2011
Peer-reviewed: Yes

Publication information

Journal: Nanotechnology
Volume: 22
Issue number: 27
Article number: 275610
ISSN (Print): 0957-4484
Ratings: 
  • Scopus rating (2011): CiteScore 6.5 SJR 1.899 SNIP 1.471
Original language: English
ASJC Scopus subject areas: Bioengineering, Chemistry(all), Electrical and Electronic Engineering, Mechanical Engineering, Mechanics of Materials, Materials Science(all)
Source: Scopus
Source ID: 79957825438

Research output: Contribution to journalArticleScientificpeer-review

Towards universal enrichment nanocoating for IR-ATR waveguides

Polymer multilayered nanocoating capable of concentrating various chemical substances at IR-ATR waveguide surfaces is described. The coating affinity to an analyte played a pivotal role in sensitivity enhancement of the IR-ATR measurements, since the unmodified waveguide did not show any analyte detection.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Frontier Photonics, Clemson University, School of Materials Science and Engineering/COMSET, University of Delaware, Massachusetts Institute of Technology
Contributors: Giammarco, J., Zdyrko, B., Petit, L., Musgraves, J. D., Hu, J., Agarwal, A., Kimerling, L., Richardson, K., Luzinov, I.
Number of pages: 3
Pages: 9104-9106
Publication date: 28 Aug 2011
Peer-reviewed: Yes

Publication information

Journal: Chemical Communications
Volume: 47
Issue number: 32
ISSN (Print): 1359-7345
Ratings: 
  • Scopus rating (2011): CiteScore 7.9 SJR 2.889 SNIP 1.326
Original language: English
ASJC Scopus subject areas: Catalysis, Electronic, Optical and Magnetic Materials, Ceramics and Composites, Chemistry(all), Surfaces, Coatings and Films, Metals and Alloys, Materials Chemistry
Source: Scopus
Source ID: 79961012632

Research output: Contribution to journalArticleScientificpeer-review

The effect of organic loading rate and retention time on hydrogen production from a methanogenic CSTR

The possibility of shifting a methanogenic process for hydrogen production by changing the process parameters viz., organic loading rate (OLR) and hydraulic retention time (HRT) was evaluated. At first, two parallel semi-continuously fed continuously stirred tank reactors (CSTR) were operated as methanogenic reactors (M1 and M2) for 78days. Results showed that a methane yield of 198-218L/kg volatile solids fed (VS fed) was obtained when fed with grass silage at an OLR of 2kgVS/m 3/d and HRT of 30days. After 78days of operation, hydrogen production was induced in M2 by increasing the OLR from 2 to 10kgVS/m 3/d and shortening the HRT from 30 to 6days. The highest H 2 yield of 42L/kgVS fed was obtained with a maximum H 2 content of 24%. The present results thus demonstrate that methanogenic process can be shifted towards hydrogen production by increasing the OLR and decreasing HRT.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Urban circular bioeconomy (UrCirBio), Jyväskylän yliopisto, University of Jyväskylä
Contributors: Pakarinen, O., Kaparaju, P., Rintala, J.
Number of pages: 6
Pages: 8952-8957
Publication date: Oct 2011
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 102
Issue number: 19
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2011): CiteScore 7.9 SJR 2.308 SNIP 2.526
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Grass silage, Hydrogen, Methane, Shifting, VFA
Source: Scopus
Source ID: 80052377734

Research output: Contribution to journalArticleScientificpeer-review

Versatile bio-ink for covalent immobilization of chimeric avidin on sol-gel substrates

A bio-ink for covalent deposition of thermostable, high affinity biotin-binding chimeric avidin onto sol-gel substrates was developed. The bio-ink was prepared from heterobifunctional crosslinker 6-maleimidohexanoic acid N-hydroxysuccinimide which was first reacted either with 3-aminopropyltriethoxysilane or 3-aminopropyldimethylethoxysilane to form silane linkers 6-maleimide- N-(3-(triethoxysilyl)propyl)hexanamide or -(ethoxydimethylsilyl)propyl)-hexanamide. C-terminal cysteine genetically engineered to chimeric avidin was reacted with the maleimide group of silane linker in methanol/PBS solution to form a suspension, which was printed on sol-gel modified PMMA film. Different concentrations of chimeric avidin and ratios between silane linkers were tested to find the best properties for the bio-ink to enable gravure or inkjet printing. Bio-ink prepared from 3-aminopropyltriethoxysilane was found to provide the highest amount of active immobilized chimeric avidin. The developed bio-ink was shown to be valuable for automated fabrication of avidin-functionalized polymer films.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Multi-scaled biodata analysis and modelling (MultiBAM), Univ of Oulu, VTT Technical Research Centre of Finland, Tampere University Hospital
Contributors: Heikkinen, J. J., Kivimäki, L., Määttä, J. A. E., Mäkelä, I., Hakalahti, L., Takkinen, K., Kulomaa, M. S., Hytönen, V. P., Hormi, O. E. O.
Number of pages: 6
Pages: 409-414
Publication date: 15 Oct 2011
Peer-reviewed: Yes

Publication information

Journal: Colloids and Surfaces B: Biointerfaces
Volume: 87
Issue number: 2
ISSN (Print): 0927-7765
Ratings: 
  • Scopus rating (2011): CiteScore 4.7 SJR 1.051 SNIP 1.27
Original language: English
ASJC Scopus subject areas: Biotechnology, Colloid and Surface Chemistry, Physical and Theoretical Chemistry, Surfaces and Interfaces
Keywords: Avidin-biotin technology, Biomolecule immobilization, Biosensing, Chimeric avidin, Maleimide, Printing, Sol-gel
Source: Scopus
Source ID: 79960384544

Research output: Contribution to journalArticleScientificpeer-review

Screening ethnically diverse human embryonic stem cells identifies a chromosome 20 minimal amplicon conferring growth advantage

The International Stem Cell Initiative analyzed 125 human embryonic stem (ES) cell lines and 11 induced pluripotent stem (iPS) cell lines, from 38 laboratories worldwide, for genetic changes occurring during culture. Most lines were analyzed at an early and late passage. Single-nucleotide polymorphism (SNP) analysis revealed that they included representatives of most major ethnic groups. Most lines remained karyotypically normal, but there was a progressive tendency to acquire changes on prolonged culture, commonly affecting chromosomes 1, 12, 17 and 20. DNA methylation patterns changed haphazardly with no link to time in culture. Structural variants, determined from the SNP arrays, also appeared sporadically. No common variants related to culture were observed on chromosomes 1, 12 and 17, but a minimal amplicon in chromosome 20q11.21, including three genes expressed in human ES cells, ID1, BCL2L1 and HM13, occurred in >20% of the lines. Of these genes, BCL2L1 is a strong candidate for driving culture adaptation of ES cells.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Integrated Technologies for Tissue Engineering Research (ITTE), University of Sheffield, International Centre for Life, A-STAR, Immunos, Royan Institute, mediaX and H*STAR Stanford University Stanford, Sheffield Children's NHS Trust, University of Nottingham, Keck School of Medicine of USC, Hebrew University of Jerusalem, Tel Aviv University, Sackler Faculty of Medicine, Cedars-Sinai Medical Institute, University of Geneva, Manchester Academic Health Sciences Centre, Cellartis AB, University of Manchester, Genome Institute of Singapore, Hoffmann-LaRoche, Seoul National University College of Medicine, Bioprocessing Technology Institute, Roslin Cells Ltd., University of Melbourne, Harvard Stem Cell Institute, University of Edinburgh, Masaryk University, WiCell Research Institute, Hopital Cantonal Fribourgois, Department of Applied Physics, Lis Maternity Hospital Israel, Central South University China, Hadassah University Medical Center, Institute of Experimental Botany of the Academy of Sciences of the Czech Republic, University College London, National Institute for Biological Standards and Control, Karolinska University Hospital, Jawaharlal Nehru Centre for Advanced Scientific Research, NYU Langone Medical Center, Shanghai Jiaotong University, Vavilov Institute of General Genetics, Reproductive Genetics Institute, Monash University, CHA University, Vrije Universiteit Brussel, Mount Sinai Hospital, GE Healthcare, UK, Kyoto Women's University, Leiden University Medical Center - LUMC, University of Helsinki, Yale School of Medicine, Viacyte, Hospital for Sick Children University of Toronto, University of New South Wales (UNSW) Australia, Gladstone Institute of Cardiovascular Disease, CSIRO Energy Centre
Contributors: Amps, K., Andrews, P. W., Anyfantis, G., Armstrong, L., Avery, S., Baharvand, H., Baker, J., Baker, D., Munoz, M. B., Beil, S., Benvenisty, N., Ben-Yosef, D., Biancotti, J. C., Bosman, A., Brena, R. M., Brison, D., Caisander, G., Camarasa, M. V., Chen, J., Chiao, E., Choi, Y. M., Choo, A. B. H., Collins, D., Colman, A., Crook, J. M., Daley, G. Q., Dalton, A., De Sousa, P. A., Denning, C., Downie, J., Dvorak, P., Montgomery, K. D., Feki, A., Ford, A., Fox, V., Fraga, A. M., Frumkin, T., Ge, L., Gokhale, P. J., Golan-Lev, T., Gourabi, H., Gropp, M., Guangxiu, L., Hampl, A., Harron, K., Healy, L., Herath, W., Holm, F., Hovatta, O., Hyllner, J., Inamdar, M. S., Irwanto, A. K., Ishii, T., Jaconi, M., Jin, Y., Kimber, S., Kiselev, S., Knowles, B. B., Kopper, O., Kukharenko, V., Kuliev, A., Lagarkova, M. A., Laird, P. W., Lako, M., Laslett, A. L., Lavon, N., Lee, D. R., Lee, J. E., Li, C., Lim, L. S., Ludwig, T. E., Ma, Y., Maltby, E., Mateizel, I., Mayshar, Y., Mileikovsky, M., Minger, S. L., Miyazaki, T., Moon, S. Y., Moore, H., Mummery, C., Nagy, A., Nakatsuji, N., Narwani, K., Oh, S. K. W., Oh, S. K., Olson, C., Otonkoski, T., Pan, F., Park, I. H., Pells, S., Pera, M. F., Pereira, L. V., Qi, O., Raj, G. S., Reubinoff, B., Robins, A., Robson, P., Rossant, J., Salekdeh, G. H., Schulz, T. C., Sermon, K., Mohamed, J. S., Shen, H., Sherrer, E., Sidhu, K., Sivarajah, S., Skottman, H., Spits, C., Stacey, G. N., Strehl, R., Strelchenko, N., Suemori, H., Sun, B., Suuronen, R., Takahashi, K., Tuuri, T., Venu, P., Verlinsky, Y., Oostwaard, D. W. V., Weisenberger, D. J., Wu, Y., Yamanaka, S., Young, L., Zhou, Q.
Number of pages: 13
Pages: 1132-1144
Publication date: Dec 2011
Peer-reviewed: Yes

Publication information

Journal: Nature Biotechnology
Volume: 29
Issue number: 12
ISSN (Print): 1087-0156
Ratings: 
  • Scopus rating (2011): CiteScore 38.7 SJR 11.749 SNIP 6.125
Original language: English
ASJC Scopus subject areas: Biotechnology, Bioengineering, Medicine(all), Molecular Medicine, Biomedical Engineering, Applied Microbiology and Biotechnology
Source: Scopus
Source ID: 83255189758

Research output: Contribution to journalArticleScientificpeer-review

Synthesis of depsipeptides from L-amino acids and lactones

By using the corresponding L-amino acid sodium as initiator, e{open}-caprolactone-depsipeptides CL-Ala and CL-Leu were prepared by the reactions of e{open}-caprolactone (CL) with L-alanine and L-leucine, respectively, and p-dioxanone-depsipeptide (PDO-Leu) was prepared by the reaction of p-dioxanone (PDO) with L leucine. Two poly(e{open}-caprolactone) oligomers (PCL-Ala and PCL-Leu) of different molecular weights with depsipeptide unit were synthesized by controlling the feed ratio of L-amino acid sodium and CL. The presence of the depsipeptide structure in these obtained products was confirmed by 1H NMR spectra and the molecular weight of the poly(e{open}-caprolactone) oligomers was measured by gel permeation chromatography (GPC). These products contain a hydroxyl group and a carboxyl group in one molecule, which means they could act as bifunctional monomers for further polymerization to prepare high molecular weight polymers. By this way, the depsipeptide unit could be introduced into the polymers and the biodegradation rates of the novel polymers could be well controlled in vivo by the tailored molecular structures.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Integrated Technologies for Tissue Engineering Research (ITTE), Tianjin University, School of Chemical Engineering and Technology
Contributors: Cao, H., Feng, Y., Wang, H., Zhang, L., Khan, M., Guo, J.
Number of pages: 7
Pages: 409-415
Publication date: Dec 2011
Peer-reviewed: Yes

Publication information

Journal: Frontiers of Chemical Science and Engineering
Volume: 5
Issue number: 4
ISSN (Print): 2095-0179
Ratings: 
  • Scopus rating (2011): CiteScore 0.7 SJR 0.23 SNIP 0.35
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all)
Keywords: e{open}-caprolactone, L-alanine, L-leucine depsipeptide, p-dioxanone
Source: Scopus
Source ID: 83355176163

Research output: Contribution to journalArticleScientificpeer-review

Conductive layers on surface modified natural fibre based substrates for printed functionality

Formation of conductive surfaces by flexographical printing has been studied using an IGT test printer with PEDOT-PSS and Ag conductive inks on coated papers. Printability of multilayer coated paper and TiO2 nanoparticle coating generated by the liquid flame spray process are compared to commercial plastic film used in printed electronics applications. The wettability of TiO2 nanoparticle coating can be altered between superhydrophobic and superhydrophilic states by ultraviolet light. It is observed that superhydrophobicity induced by TiO2 nanoparticles results in poorer ink setting and hence lower conductivities with water-based PEDOT:PSS ink. Therefore, we observe conductivity only after several successive prints. On contrary, we observe several orders of magnitude better conductivities when using a silver ink in flexography. It is believed that sustainable natural fibre based substrates will find more applications in printed electronics application in the future.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Materials Science, Department of Physics, Engineering materials science and solutions (EMASS), Abo Akad Univ, Abo Akademi University, Dept Phys, Paper Converting and Packaging Technology, Aerosol Physics Laboratory, Hokkai-Gakuen University
Contributors: Valtakari, D., Bollström, R., Tuominen, M., Teisala, H., Aromaa, M., Toivakka, M., Kuusipalo, J., Mäkelä, J. M., Uozumi, J., Saarinen, J. J.
Publication date: 2012

Host publication information

Title of host publication: AIChE 2012 - 2012 AIChE Annual Meeting, Conference Proceedings
ISBN (Print): 9780816910731
ASJC Scopus subject areas: Chemical Engineering(all), Chemistry(all)
Source: Scopus
Source ID: 84871794294

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Osteogenic medium is superior to growth factors in differentiation of human adipose stem cells towards boneforming cells in 3D culture

Human adipose stem cells (hASCs) have been recently used to treat bone defects in clinical practice. Yet there is a need for more optimal scaffolds and cost-effective approaches to induce osteogenic differentiation of hASCs. Therefore, we compared the efficiency of bone morphogenetic proteins (BMP-2 and BMP-7), vascular endothelial growth factor (VEGF), and osteogenic medium (OM) for the osteo-induction of hASCs in 3D culture. In addition, growth factors were tested in combination with OM. Commercially available bioactive glass scaffolds (BioRestore) and biphasic calcium phosphate granules (BoneCeramic) were evaluated as prospective carriers for hASCs. Both biomaterials supported hASC-viability, but BioRestore resulted in higher cell number than BoneCeramic, whereas BoneCeramic supported more significant collagen production. The most efficient osteo-induction was achieved with plain OM, promoting higher alkaline phosphatase activity and collagen production than growth factors. In fact, treatment with BMP-2 or VEGF did not increase osteogenic differentiation or cell number significantly more than maintenance medium with either biomaterial. Moreover, BMP-7 treatment consistently inhibited proliferation and osteogenic differentiation of hASCs. Interestingly, there was no benefit from growth factors added to OM. This is the first study to demonstrate that OM enhances hASC-differentiation towards bone-forming cells significantly more than growth factors in 3D culture.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Electronics and Communications Engineering, Integrated Technologies for Tissue Engineering Research (ITTE), Tampere University Hospital, University of Twente, BioMediTech, Onbone Oy, Univ of Oulu
Contributors: Tirkkonen, L., Haimi, S., Huttunen, S., Wolff, J., Pirhonen, E., Sándor, G. K., Miettinen, S.
Number of pages: 15
Pages: 144-158
Publication date: 2012
Peer-reviewed: Yes

Publication information

Journal: European Cells and Materials
Volume: 25
ISSN (Print): 1473-2262
Ratings: 
  • Scopus rating (2012): CiteScore 0.9 SJR 0.294 SNIP 0.183
Original language: English
ASJC Scopus subject areas: Biochemistry, Cell Biology, Bioengineering, Biomedical Engineering, Biomaterials, Medicine(all)
Keywords: 3D scaffolds, Adipose stem cells, Bioactive glass, Biphasic calcium phosphate, Bone tissue engineering, Growth factors, In vitro culture, Mesenchymal stem cells, Osteogenic differentiation
Source: Scopus
Source ID: 84878388600

Research output: Contribution to journalArticleScientificpeer-review

Utilization of agrowaste polymers in PVC/NBR alloys: Tensile, thermal, and morphological properties

Poly(vinyl chloride)/nitrile butadiene rubber (PVC/NBR) alloys were melt-mixed using a Brabender Plasticorder at 180 °C and 50rpm rotor speed. Alloys obtained by melt mixing from PVC and NBR were formulated with wood-flour- (WF-) based olive residue, a natural byproduct from olive oil extraction industry. WF was progressively increased from 0 to 30phr. The effects of WF loadings on the tensile properties of the fabricated samples were inspected. The torque rheometry, which is an indirect indication of the melt strength, is reported. The pattern of water uptake for the composites was checked as a function WF loading. The fracture mode and the quality of bonding of the alloy with and without filler are studied using electron scanning microscope (SEM).

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Engineering materials science and solutions (EMASS), Al Balqa Applied University, Leibniz-Institut für Polymerforschung Dresden E.V.
Contributors: Mousa, A., Heinrich, G., Kretzschmar, B., Wagenknecht, U., Das, A.
Publication date: 2012
Peer-reviewed: Yes

Publication information

Journal: INTERNATIONAL JOURNAL OF CHEMICAL ENGINEERING
Article number: 121496
ISSN (Print): 1687-806X
Ratings: 
  • Scopus rating (2012): CiteScore 1.2 SJR 0.408 SNIP 0.784
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all)
Source: Scopus
Source ID: 84861026655

Research output: Contribution to journalArticleScientificpeer-review

Human adipose tissue extract induces angiogenesis and adipogenesis in vitro

The induction of adequate vascularization, a major challenge in tissue engineering, has been tried with numerous methods but with unsatisfactory results. Adipose tissue, an active endocrine organ with dense vasculature, secretes a wide number of angiogenic and adipogenic factors and seems an attractive source for these bioactive factors. We produced a novel cell-free extract from mature human adipose tissue (adipose tissue extract [ATE]) and analyzed the ability of this extract to induce angiogenesis and adipogenesis in vitro and studied the cytokine and growth factor composition of ATE with ELISA and cytokine array. We demonstrate that ATE, when added as cell culture supplement, effectively induced triglyceride accumulation in human adipose stem cells at concentrations from 200 μg/mL upward in less than a week and caused elevated levels of adipocyte differentiation markers (proliferator-activated receptor gamma and acyl-CoA-binding protein) when treated with at least 350 μg/mL of ATE. ATE induced angiogenesis from 450 μg/mL upward after a week in vitro. ATE contained numerous angiogenic and adipogenic factors, for example, vascular endothelial growth factor, basic fibroblast growth factor, interleukin-6, adiponectin, angiogenin, leptin, and insulin-like growth factor-I, as well as lower levels of a wide variety of other cytokines. We here present a novel cell-free angiogenesis-and adipogenesis-inducing agent that is cell-free and easy to produce, and its effect is dose dependent and its composition can be easily modified. Therefore, ATE is a promising novel agent to be used for angiogenesis induction to overcome the challenge of vascularization and for adipogenesis induction in a wide variety of tissue engineering applications in vitro and in vivo. ATE is also efficient for reproduction and modeling of natural adipogenesis in vitro for, for example, obesity and diabetes studies.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Integrated Technologies for Tissue Engineering Research (ITTE), Tampere University Hospital, University of Tampere, Medical School, BioMediTech
Contributors: Sarkanen, J. R., Kaila, V., Mannerström, B., Räty, S., Kuokkanen, H., Miettinen, S., Ylikomi, T.
Number of pages: 9
Pages: 17-25
Publication date: 1 Jan 2012
Peer-reviewed: Yes

Publication information

Journal: Tissue Engineering Part A
Volume: 18
Issue number: 1-2
ISSN (Print): 1937-3341
Ratings: 
  • Scopus rating (2012): CiteScore 8.5 SJR 2.029 SNIP 1.201
Original language: English
ASJC Scopus subject areas: Bioengineering, Biochemistry, Biomedical Engineering, Biomaterials, Medicine(all)
Source: Scopus
Source ID: 84855405319

Research output: Contribution to journalArticleScientificpeer-review

Demonstration of increased lipid accumulation potential of stigeoclonium sp., Kütz. BUM11007 under nitrogen starved regime: A new source of lipids for biodiesel production

The fresh water microalga Stigeoclonium sp., Kütz. BUM11007 was investigated for their property to be a suitable candidate for biodiesel production. The growth, lipid content and fatty acid profiles of the organism were determined under both normal and nitrogen free conditions with Chu 10 medium. A maximum biomass concentration 2.84±0.11 g/l with lipid content 138.21±9.82 mg/g and lipid productivity 15.07±0.67 mg/l·d was obtained under nutrient sufficient condition. In contrast to which under nitrogen depleted regimes in a two phase culturing system, biomass yield 2.798±0.18 g/l with increased lipid content 407.18 ± 11.6 mg/g at lipid productivity 43.68 ± 1.82 mg/l · d were recorded. The fatty acid methyl ester profiles revealed the presence of 16:0 (palmitic), 18:0 (stearic), 18:1 (oleic) and 18:2 (linoleic) methyl esters as the major components. The results show the ability of the algae to be a promising feedstock source for biodiesel production.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Urban circular bioeconomy (UrCirBio), Bharathidasan University, Fisk University
Contributors: Praveenkumar, R., Johncy, K., MubarakAli, D., Vijayan, D., Thajuddin, N., Gunasekaran, M.
Number of pages: 5
Pages: 209-213
Publication date: Apr 2012
Peer-reviewed: Yes

Publication information

Journal: Journal of Biobased Materials and Bioenergy
Volume: 6
Issue number: 2
ISSN (Print): 1556-6560
Ratings: 
  • Scopus rating (2012): CiteScore 1.8 SJR 0.458 SNIP 0.664
Original language: English
ASJC Scopus subject areas: Biomaterials, Bioengineering, Renewable Energy, Sustainability and the Environment
Keywords: Biodiesel, FAME Production, Lipid Extraction, Nitrogen Starvation, Stigeoclonium
Source: Scopus
Source ID: 84865034973

Research output: Contribution to journalArticleScientificpeer-review

Highly exfoliated natural rubber/Clay composites by "propping-open procedure": The influence of fatty-acid chain length on exfoliation

A high degree of exfoliation of MMT in NR is achieved by using the so-called "propping-open approach" in which a stepwise expansion of the interlayer spacing of MMT takes place. The nanostructure is characterized by WAXD and TEM which indicate different extents of clay dispersion depending on the fatty-acid chain length. Curing kinetics of different nanocomposites is studied and interestingly low activation energies of the vulcanization process are observed in the case of NR/EMMT nanocomposites. The incorporation of EMMT dramatically affects composite properties whereas DMA indicates significant reduction of tan δ peak height and the tensile strength approximately doubles from 14 to 30 MPa with only 5 phr EMMT.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Engineering materials science and solutions (EMASS), Leibniz-Institut für Polymerforschung Dresden E.V., Vodafone Department of Mobile Communications Systems
Contributors: Rooj, S., Das, A., Stöckelhuber, K. W., Reuter, U., Heinrich, G.
Number of pages: 15
Pages: 369-383
Publication date: Apr 2012
Peer-reviewed: Yes

Publication information

Journal: Macromolecular Materials and Engineering
Volume: 297
Issue number: 4
ISSN (Print): 1438-7492
Ratings: 
  • Scopus rating (2012): CiteScore 3.7 SJR 0.963 SNIP 1.187
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all), Organic Chemistry, Polymers and Plastics, Materials Chemistry
Keywords: curing kinetics, exfoliation, Mooney-Rivlin equation, nanocomposites, propping-open approach
Source: Scopus
Source ID: 84859811037

Research output: Contribution to journalArticleScientificpeer-review

Structural characteristics and flammability of fire retarding EPDM/layered double hydroxide (LDH) nanocomposites

A high performance elastomeric flame retardant nanocomposite was prepared which was based on maleic anhydride grafted ethylene-propylene-diene terpolymer (mEPDM), a one-step synthesised organo-layered double hydroxide (LDH), and an intumescent flame retardant (FR) comprised of pentaerythritol (PER), ammonium polyphosphate (APP) and methyl cyanoacetate (MCA). The morphology, fire behavior and mechanical properties of the flame-retarded mEPDM/LDH nanocomposite have been studied in detail. Wide angle X-ray scattering (WAXS), small angle X-ray scattering (SAXS) and TEM observation confirmed an exfoliated structure of LDH in a particular composite containing 2 phr (parts per hundred) LDH and 38 phr FR. As an effective flame retardant synergistic agent, MgAl-LDH shows a significant decrease in the heat release rate (HRR), low mass loss (ML) and low fire growth rate (FIGRA) of the nanocomposite. The flame retardant mechanism has been proposed, which is mainly due to the condensed phase flame retardant mechanism to form reinforced char layers during combustion, leading to the low volatiles produced. Moreover, as far as the mechanical properties of the vulcanizates are concerned, in all cases of flame retardant mEPDM and flame retarded mEPDM/LDH nanocomposites, they exhibit superior values compared to the gum compound.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Engineering materials science and solutions (EMASS), Leibniz-Institut für Polymerforschung Dresden E.V., Vodafone Department of Mobile Communications Systems
Contributors: Wang, D. Y., Das, A., Leuteritz, A., Mahaling, R. N., Jehnichen, D., Wagenknecht, U., Heinrich, G.
Number of pages: 7
Pages: 3927-3933
Publication date: 21 Apr 2012
Peer-reviewed: Yes

Publication information

Journal: RSC Advances
Volume: 2
Issue number: 9
ISSN (Print): 2046-2069
Ratings: 
  • Scopus rating (2012): CiteScore 0.9 SJR 0.872 SNIP 0.619
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all), Chemistry(all)
Source: Scopus
Source ID: 84863098130

Research output: Contribution to journalArticleScientificpeer-review

Molecular mechanisms of ion-specific effects on proteins

The specific binding sites of Hofmeister ions with an uncharged 600-residue elastin-like polypeptide, (VPGVG) 120, were elucidated using a combination of NMR and thermodynamic measurements along with molecular dynamics simulations. It was found that the large soft anions such as SCN - and I - interact with the polypeptide backbone via a hybrid binding site that consists of the amide nitrogen and the adjacent α-carbon. The hydrocarbon groups at these sites bear a slight positive charge, which enhances anion binding without disrupting specific hydrogen bonds to water molecules. The hydrophobic side chains do not contribute significantly to anion binding or the corresponding salting-in behavior of the biopolymer. Cl - binds far more weakly to the amide nitrogen/α-carbon binding site, while SO 4 2- is repelled from both the backbone and hydrophobic side chains of the polypeptide. The Na + counterions are also repelled from the polypeptide. The identification of these molecular-level binding sites provides new insights into the mechanism of peptide-anion interactions.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Computational Science X (CompX), Texas A and M University, Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic
Contributors: Rembert, K. B., Paterová, J., Heyda, J., Hilty, C., Jungwirth, P., Cremer, P. S.
Number of pages: 8
Pages: 10039-10046
Publication date: 20 Jun 2012
Peer-reviewed: Yes

Publication information

Journal: Journal of the American Chemical Society
Volume: 134
Issue number: 24
ISSN (Print): 0002-7863
Ratings: 
  • Scopus rating (2012): CiteScore 17.4 SJR 6.211 SNIP 2.374
Original language: English
ASJC Scopus subject areas: Chemistry(all), Catalysis, Biochemistry, Colloid and Surface Chemistry
Source: Scopus
Source ID: 84862532625

Research output: Contribution to journalArticleScientificpeer-review

Impact of biodiesel application at various blending ratios on passenger cars of different fueling technologies

The effect of biodiesel on emissions of diesel passenger cars is a combination of the fuel properties, the blending ratio, and the vehicle technology. In this study, saturated and unsaturated biodiesel fuels were tested neat (B100) and in 30% blend with fossil diesel (B30) on two Euro 3 diesel passenger cars of different engine technologies, namely common rail and unit injector. The measured dataset is enlarged by introducing B10 results from an earlier study [15] in order to produce generalized conclusions over a wider range of blends. None of these vehicles was equipped with a particle filter and different conclusions might be reached for filter-equipped vehicles. The results indicate that the influence of biodiesel on pollutant emissions primarily depends on the blending ratio and secondly on the level of unsaturation and engine technology. Tailpipe CO 2, NO x and PM emissions with biodiesel varied from -1% to +3%, -1% to 14%, and -18% to -35%, respectively, compared to fossil diesel. The difference over fossil diesel generally increased with an increasing blending ratio. CO and HC emissions increased over the fossil diesel but remained at low levels and did not threaten the compliance of the vehicles with their respective emission limits. Use of biodiesel on the common rail vehicle led to a smaller NO x increase and a higher PM reduction than in the unit-injector case. The unsaturated fuel generally led to higher NO x emissions from both engine technologies. However, the maximum blending ratio of saturated biodiesel is limited to around B30 due to cold-flow limitations. Hence, the saturated vs. unsaturated species ratio should be carefully designed in market fuels in order to optimize environmental and operational benefits. Overall, it appears that blends up to 10% v/v may be introduced with limited urban air quality implications.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Urban circular bioeconomy (UrCirBio), Aristotle University of Thessaloniki, Laboratory of Applied Thermodynamics, European Commission-JRC
Contributors: Kousoulidou, M., Ntziachristos, L., Fontaras, G., Martini, G., Dilara, P., Samaras, Z.
Number of pages: 7
Pages: 88-94
Publication date: Aug 2012
Peer-reviewed: Yes

Publication information

Journal: Fuel
Volume: 98
ISSN (Print): 0016-2361
Ratings: 
  • Scopus rating (2012): CiteScore 5.6 SJR 1.813 SNIP 2.387
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all), Fuel Technology, Energy Engineering and Power Technology, Organic Chemistry
Keywords: Biodiesel, Fuel injection technology, Unsaturation level, Vehicle emissions
Source: Scopus
Source ID: 84861986728

Research output: Contribution to journalArticleScientificpeer-review

Biomimetic surface modification of polycarbonateurethane film via phosphorylcholine-graft for resisting platelet adhesion

Phosphorylcholine groups were covalently introduced onto a polycarbonateurethane (PCU) surface in order to create a biomimetic structure on the polymer surfaces. After introducing primary amine groups onto the polymer surface by 1,6-hexanediamine, phosphorylcholine groups were covalently linked onto the surface by the reductive amination between the amino group and the aldehyde group of phosphorylcholine glyceraldehyde (PCGA). The results of water contact angle test, X-ray photoelectron spectroscopy (XPS), and X-ray fluorescence spectrometer (XRF) analysis of the modified films indicated that PCGA had already been covalently linked to the PCU surface. The topographies and surface roughnesses were both imaged and measured by atomic force microscopy (AFM). Scanning electron microscopy (SEM) observation of the PCU films after treatment with platelet-rich plasma demonstrated that platelets had rarely adhered to the surface of the PCGA-grafted PCU films but had mainly adhered to the surface of the blank PCU films. The platelet adhesion result indicated that the PC modified PCU films could resist platelet adhesion after grafting with PCGA, and that these PCGA-grafted PCU materials, potentially, might be applied as blood-contacting materials.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Integrated Technologies for Tissue Engineering Research (ITTE), Tianjin University, School of Chemical Engineering and Technology
Contributors: Gao, W., Feng, Y., Lu, J., Khan, M., Guo, J.
Number of pages: 7
Pages: 1063-1069
Publication date: Oct 2012
Peer-reviewed: Yes

Publication information

Journal: Macromolecular Research
Volume: 20
Issue number: 10
ISSN (Print): 1598-5032
Ratings: 
  • Scopus rating (2012): CiteScore 2.2 SJR 0.569 SNIP 0.801
Original language: English
ASJC Scopus subject areas: Organic Chemistry, Materials Chemistry, Polymers and Plastics, Chemical Engineering(all)
Keywords: Biomimetic, Phosphorylcholine glyceraldehydes, Platelet adhesion, Polycarbonateurethane, Surface modification
Source: Scopus
Source ID: 84867230066

Research output: Contribution to journalArticleScientificpeer-review

Fabrication of ssDNA/oligo(ethylene glycol) monolayers and complex nanostructures by an irradiation-promoted exchange reaction

Creative design: An approach to preparing mixed monolayers of thiolated single-stranded DNA (ssDNA) and oligo(ethylene glycol)s (OEG-AT) in a broad range of compositions as well as ssDNA/OEG-AT patterns of any required shape (see top figure) has been shown. A combination of this approach with surface-initiated enzymatic polymerization allows complex 3D DNA nanostructures to be sculpted with high spatial precision (bottom).

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Integrated Technologies for Tissue Engineering Research (ITTE), Universitat Heidelberg, Duke University
Contributors: Khan, M. N., Tjong, V., Chilkoti, A., Zharnikov, M.
Number of pages: 4
Pages: 10303-10306
Publication date: 8 Oct 2012
Peer-reviewed: Yes

Publication information

Journal: Angewandte Chemie (International Edition)
Volume: 51
Issue number: 41
ISSN (Print): 1433-7851
Ratings: 
  • Scopus rating (2012): CiteScore 16.5 SJR 6.407 SNIP 2.329
Original language: English
ASJC Scopus subject areas: Chemistry(all), Catalysis
Keywords: chemical lithography, DNA structures, monolayers, nanostructures, polymer brushes
Source: Scopus
Source ID: 84867091572

Research output: Contribution to journalArticleScientificpeer-review

Influence of ionic liquids on the dielectric relaxation behavior of CNT based elastomer nanocomposites

The influence of an imidazolium type ionic liquid (IL) on the relaxation behavior of carbon-nanotube (CNT) based polychloroprene nanocomposites prepared by melt mixing has been investigated by broadband dielectric spectroscopy. It is demonstrated that the presence of the ionic liquid modifies the relaxation behavior of the pure rubber matrix and leads to a significant increase of the conductivity for the CNT/rubber composites. For the unfilled rubber, a distinct glass transition of the IL is observed for high concentrations demonstrating that the IL forms a separate phase. The increased conductivity of the CNT-filled rubber composites is related to a physical coupling between CNTs and rubber matrix mediated by IL leading to a better dispersion of the CNTs.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Engineering materials science and solutions (EMASS), Deutsches Institut für Kautschuktechnologie e.V., Leibniz-Institut für Polymerforschung Dresden E.V., Technische Universität Dresden, Vodafone Department of Mobile Communications Systems
Contributors: Steinhauser, D., Subramaniam, K., Das, A., Heinrich, G., Klüppel, M.
Number of pages: 10
Pages: 927-936
Publication date: Nov 2012
Peer-reviewed: Yes

Publication information

Journal: Express Polymer Letters
Volume: 6
Issue number: 11
ISSN (Print): 1788-618X
Ratings: 
  • Scopus rating (2012): CiteScore 3.2 SJR 0.915 SNIP 1.605
Original language: English
ASJC Scopus subject areas: Polymers and Plastics, Materials Chemistry, Chemical Engineering(all), Organic Chemistry, Physical and Theoretical Chemistry
Keywords: Dielectric spectroscopy, Ionic liquid, Nanocomposites, Relaxation dynamics, Rubber
Source: Scopus
Source ID: 84866131281

Research output: Contribution to journalArticleScientificpeer-review

New reports on anti-bacterial and anti-candidal activities of fatty acid methyl esters (FAME) obtained from Scenedesmus bijugatus var. bicellularis biomass

The present study evaluates the efficiency of fatty acid methyl esters (FAMEs) obtained from microalgal (Scenedesmus bijugatus var bicellularis) biomass as an antimicrobial agent against Staphylococcus aureus, Escherichia coli and Candida albicans. The FAME profiles were determined through Gas Chromatography (GC) with a Flame Ionization detector (FID). The FAMEs showed inhibitory activity against all three microorganisms and thereby exhibited both anti-bacterial and anti-candidal activity. GC-FID analysis reveals about 30 different FAMEs. Out of these, various pharmacologically active FAMEs like stearic acid methyl ester (C18:0) (0.6% w/w), oleic acid methyl ester (C18:1) (1% w/w), linoleic acid methyl ester (C18:2) (1.40% w/w), linolenic acid methyl ester (C18:3) (6.26%), eicosapentanoic acid methyl ester (C20:5) (1.13% w/w), erucic acid methyl ester (C22:1) (1.03% w/w) and docosahexenoic acid methyl ester (C22:6) (2.27% w/w) were detected, which accounted for the bioactivity. These results clearly indicate that the FAMEs of S. bijugatus var. bicellularis have strong antimicrobial properties and could thus be used as an effective source against microbial diseases.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Urban circular bioeconomy (UrCirBio), Bharathidasan University, King Saud University College of Science
Contributors: Mubarakali, D., Praveenkumar, R., Shenbagavalli, T., Mari Nivetha, T., Parveez Ahamed, A., Al-Dhabi, N. A., Thajuddin, N.
Number of pages: 5
Pages: 11552-11556
Publication date: 28 Nov 2012
Peer-reviewed: Yes

Publication information

Journal: RSC Advances
Volume: 2
Issue number: 30
ISSN (Print): 2046-2069
Ratings: 
  • Scopus rating (2012): CiteScore 0.9 SJR 0.872 SNIP 0.619
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all), Chemistry(all)
Source: Scopus
Source ID: 84868128339

Research output: Contribution to journalArticleScientificpeer-review

Improving the effect of a nanoscale barrier coating on BOPP film properties by surface pretreatments

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Materials Science, Engineering materials science and solutions (EMASS), Lappeenranta University of Technology, Paper Converting and Packaging Technology
Contributors: Lahtinen, K., Lahti, J., Johansson, P., Seppänen, T., Cameron, D. C.
Number of pages: 25
Pages: 469-493
Publication date: 2013

Host publication information

Title of host publication: 14th European PLACE Conference 2013
Volume: 1
Publisher: TAPPI Press
ISBN (Electronic): 9781510815568
ASJC Scopus subject areas: Media Technology, Chemical Engineering(all), Chemistry(all), Mechanical Engineering, Materials Science(all)
Source: Scopus
Source ID: 84962833172

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

A 'clusters-in-liquid' method for calculating infrared spectra identifies the proton-transfer mode in acidic aqueous solutions

In liquid water the transfer of an excess proton between two water molecules occurs through the Zundel cation, H 2 O···H + ···OH 2. The proton-transfer mode is the asymmetric stretch of the central O···H + ···O moiety, but there is no consensus on its identification in the infrared spectra of acidic aqueous solutions. Also, in experiments with protonated gas-phase water clusters, its position shifts with cluster size, which makes its relationship with solution spectra unclear. Here we introduce a 'clusters-in-liquid' approach for calculating the infrared spectrum from any set of charges, even single protons. We apply this procedure to multistate empirical valence-bond trajectories of protonated liquid water and to ab initio molecular dynamics of the protonated water dimer and hexamer in the gas phase. The calculated proton-transfer mode is manifested in both systems as a peak near 1,740% cm -1, in quantitative agreement with a band of similar frequency in the experimental infrared spectrum of protonated water clusters.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Computational Science X (CompX), Tallinn Technical University, Institute of Chemistry, Hebrew University of Jerusalem
Contributors: Kulig, W., Agmon, N.
Number of pages: 7
Pages: 29-35
Publication date: Jan 2013
Peer-reviewed: Yes

Publication information

Journal: Nature Chemistry
Volume: 5
Issue number: 1
ISSN (Print): 1755-4330
Ratings: 
  • Scopus rating (2013): CiteScore 28.8 SJR 8.691 SNIP 3.664
Original language: English
ASJC Scopus subject areas: Chemistry(all), Chemical Engineering(all)
Source: Scopus
Source ID: 84871565081

Research output: Contribution to journalArticleScientificpeer-review

A potential nonthrombogenic small-diameter vascular scaffold with polyurethane/poly(ethylene glycol) hybrid materials by electrospinning technique

A small-diameter vascular graft (inner diameter 4 mm) was fabricated from polyurethane (PU) and poly(ethylene glycol) (PEG) solutions by electrospinning technology. The fiber diameter decreased from 1023±185 nm to 394±106 nm with increasing weight ratio of PEG in electrospinning solutions. The PU/PEG scaffolds showed randomly nanofibrous morphology and well-interconnected porous structure. The hydrophilicity of these scaffolds was improved significantly with increasing weight ratio of PEG. The mechanical properties of electrospun PU/PEG scaffolds were obviously different from that of pure PU scaffold, which was caused by plasticizing or hardening effect imparted by PEG composition. Under hydrated state, the PU/PEG scaffolds demonstrated low mechanical performance due to the hydrophilic property of materials. Compared with dry PU/PEG scaffolds with the same weight ratio of PEG, the tensile strength and elastic modulus of hydrated PU/PEG scaffolds decreased significantly, while the elongation at break increased. The results demonstrated that the electrospun PU/PEG hybrid tubular scaffolds are potential candidates for artificial blood vessels.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Integrated Technologies for Tissue Engineering Research (ITTE), Tianjin University, School of Chemical Engineering and Technology
Contributors: Wang, H., Feng, Y., Zhao, H., Fang, Z., Khan, M., Guo, J.
Number of pages: 5
Pages: 1578-1582
Publication date: Feb 2013
Peer-reviewed: Yes

Publication information

Journal: Journal Nanoscience and Nanotechnology
Volume: 13
Issue number: 2
ISSN (Print): 1533-4880
Ratings: 
  • Scopus rating (2013): CiteScore 2.3 SJR 0.339 SNIP 0.545
Original language: English
ASJC Scopus subject areas: Condensed Matter Physics, Chemistry(all), Materials Science(all), Bioengineering, Biomedical Engineering
Keywords: Electrospinning, Nanofiber, Poly(ethylene glycol), Polyurethane, Vascular scaffold
Source: Scopus
Source ID: 84876246258

Research output: Contribution to journalArticleScientificpeer-review

Chemically tailored dielectric-to-metal transition for the design of metamaterials from nanoimprinted colloidal nanocrystals

We demonstrate optical metamaterial design using colloidal gold nanocrystal building blocks. In the solid state, chemically exchanging the nanocrystals' surface-capping molecules provides a tailorable dielectric-to-metal transition exhibiting a 1010 range in DC conductivity and dielectric permittivity ranging from everywhere positive to everywhere negative throughout the visible-to-near-IR. Direct, wide-area nanoimprinting of subwavelength superstructures at room temperature, on plastic and glass substrates, affords plasmonic resonances ranging from 660 to 1070 nm, in agreement with numerical simulations.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: University of Pennsylvania, Department of Electrical and Systems Engineering
Contributors: Fafarman, A. T., Hong, S. H., Caglayan, H., Ye, X., Diroll, B. T., Paik, T., Engheta, N., Murray, C. B., Kagan, C. R.
Number of pages: 8
Pages: 350-357
Publication date: 13 Feb 2013
Peer-reviewed: Yes

Publication information

Journal: Nano Letters
Volume: 13
Issue number: 2
ISSN (Print): 1530-6984
Ratings: 
  • Scopus rating (2013): CiteScore 22.6 SJR 9.081 SNIP 3.355
Original language: English
ASJC Scopus subject areas: Bioengineering, Chemistry(all), Materials Science(all), Condensed Matter Physics, Mechanical Engineering
Keywords: ammonium thiocyanate, dielectric function, gold nanoparticles, ligand exchange, Plasmonics, soft lithography

Bibliographical note

EXT="Caglayan, Humeyra"

Source: Scopus
Source ID: 84873680258

Research output: Contribution to journalArticleScientificpeer-review

Fabrication of a sub-10 nm silicon nanowire based ethanol sensor using block copolymer lithography

This paper details the fabrication of ultrathin silicon nanowires (SiNWs) on a silicon-on-insulator (SOI) substrate as an electrode for the electro-oxidation and sensing of ethanol. The nanowire surfaces were prepared by a block copolymer (BCP) nanolithographic technique using low molecular weight symmetric poly(styrene)-block-poly(methyl methacrylate) (PS-b-PMMA) to create a nanopattern which was transferred to the substrate using plasma etching. The BCP orientation was controlled using a hydroxyl-terminated random polymer brush of poly(styrene)-random-poly(methyl methacrylate) (HO-PS-r-PMMA). TEM cross-sections of the resultant SiNWs indicate an anisotropic etch process with nanowires of sub-10 nm feature size. The SiNWs obtained by etching show high crystallinity and there is no evidence of defect inclusion or amorphous region production as a result of the pattern transfer process. The high density of SiNWs at the substrate surface allowed the fabrication of a sensor for cyclic voltammetric detection of ethanol. The sensor shows better sensitivity to ethanol and a faster response time compared to widely used polymer nanocomposite based sensors.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Frontier Photonics, Materials Chemistry and Analysis Group, University College Cork, Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Tyndall National Institute at National University of Ireland, Cork, Collinstown Industrial Estate
Contributors: Rasappa, S., Borah, D., Faulkner, C. C., Lutz, T., Shaw, M. T., Holmes, J. D., Morris, M. A.
Publication date: 15 Feb 2013
Peer-reviewed: Yes

Publication information

Journal: Nanotechnology
Volume: 24
Issue number: 6
Article number: 065503
ISSN (Print): 0957-4484
Ratings: 
  • Scopus rating (2013): CiteScore 6.9 SJR 1.602 SNIP 1.27
Original language: English
ASJC Scopus subject areas: Bioengineering, Chemistry(all), Electrical and Electronic Engineering, Mechanical Engineering, Mechanics of Materials, Materials Science(all)
Source: Scopus
Source ID: 84872971946

Research output: Contribution to journalArticleScientificpeer-review

The sensitivity of random polymer brush-lamellar polystyrene-b-polymethylmethacrylate block copolymer systems to process conditions

The use of random copolymer brushes (polystyrene- r-polymethylmethacrylate - PS- r-PMMA) to 'neutralise' substrate surfaces and ordain perpendicular orientation of the microphase separated lamellae in symmetric polystyrene- b-polymethylmethacrylate (PS- b-PMMA) block copolymers (BCPs) is well known. However, less well known is how the brushes interact with both the substrate and the BCP, and how this might change during thermal processing. A detailed study of changes in these films for different brush and diblock PS- b-PMMA molecular weights is reported here. In general, self-assembly and pattern formation is altered little, and a range of brush molecular weights are seen to be effective. However, on extended anneal times, the microphase separated films can undergo dimension changes and loss of order. This process is not related to any complex microphase separation dynamics but rather a degradation of methacrylate components in the film. The data suggest that care must be taken in interpretation of structural changes in these systems as being due to BCP only effects.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Frontier Photonics, Tyndall National Institute at National University of Ireland, Cork, Materials Chemistry and Analysis Group, University College Cork, Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Leixlip Co.
Contributors: Borah, D., Rasappa, S., Senthamaraikannan, R., Shaw, M. T., Holmes, J. D., Morris, M. A.
Number of pages: 11
Pages: 192-202
Publication date: 1 Mar 2013
Peer-reviewed: Yes

Publication information

Journal: Journal of Colloid and Interface Science
Volume: 393
Issue number: 1
ISSN (Print): 0021-9797
Ratings: 
  • Scopus rating (2013): CiteScore 6.1 SJR 1.195 SNIP 1.437
Original language: English
ASJC Scopus subject areas: Electronic, Optical and Magnetic Materials, Biomaterials, Surfaces, Coatings and Films, Colloid and Surface Chemistry
Keywords: Microphase separation, Polymer brush, Polystyrene-b-polymethylmethacrylate, Polystyrene-r-polymethylmethacrylate, Surface morphology
Source: Scopus
Source ID: 84873060382

Research output: Contribution to journalArticleScientificpeer-review

Immobilized bioactive agents onto polyurethane surface with heparin and phosphorylcholine group

Heparin (HEP) and phosphorylcholine groups (PC) were grafted onto the polyurethane (PU) surface in order to improve biocompatibility and anticoagulant activity. After the surface grafting sites of PU were amplified with the primary amine groups of polyethylenimine (PEI), heparin was covalently linked onto the surface by the reaction between the amino group and the carboxyl group. PC groups were covalently immobilized on the PU-PEI surface through the reaction between the amino group and the aldehyde group of phosphorylcholine glyceraldehyde (PCGA). The surface density of primary amine groups was determined by a ninhydrin assay. The amino group density reached a maximum of 0.88 μmol/cm2 upon incorporation of 10 wt% PEI. The amount of heparin covalently immobilized on the PU-PEI surface was determined by the toluidine blue method. The grafting chemistry resulted in the comparatively dense immobilization of HEP (2.6 μg/cm2) and PC to the PU-PEI surfaces. The HEP and PC modified surfaces were characterized by water uptake (PU 0.15 mg/cm2, PU-PEI 3.54 mg/cm2, PU-HEP 2.04 mg/cm2, PU-PC 2.38 mg/cm2), water contact angle (PU 95.3, PU-PEI 34.0, PU-HEP 39.5, PU-PC 37.2), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and scanning electron microscope (SEM). The results demonstrated that the PUPEI surface was successfully grafted with HEP and PC. The hydrophilicity and hemocompatibility of these grafted surfaces were significantly improved. These results suggested that the PU-HEP and PU-PC composite films are promising candidates for blood contacting tissue engineering.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Integrated Technologies for Tissue Engineering Research (ITTE), Tianjin University, Shihezi University, School of Chemical Engineering and Technology, Tianjin Chest Hospital
Contributors: Tan, M., Feng, Y., Wang, H., Zhang, L., Khan, M., Guo, J., Chen, Q., Liu, J.
Number of pages: 9
Pages: 541-549
Publication date: May 2013
Peer-reviewed: Yes

Publication information

Journal: Macromolecular Research
Volume: 21
Issue number: 5
ISSN (Print): 1598-5032
Ratings: 
  • Scopus rating (2013): CiteScore 2.7 SJR 0.553 SNIP 0.769
Original language: English
ASJC Scopus subject areas: Organic Chemistry, Materials Chemistry, Polymers and Plastics, Chemical Engineering(all)
Keywords: hemocompatibility, heparin, phosphorylcholine group, polyethylenimine, polyurethane
Source: Scopus
Source ID: 84877763417

Research output: Contribution to journalArticleScientificpeer-review

Screening pretreatment methods to enhance thermophilic anaerobic digestion of pulp and paper mill wastewater treatment secondary sludge

The effect of hydrothermal (150°C for 10min and 70°C for 40min), enzymatic (Accelerase 1500, 0.07g/g volatile solids (VS)), ultrasound (45kHz for 30min) and chemical pretreatments (HNO3 at pH3 and NaOH at pH12) alone or in combination on the chemical composition and methane yield of the pulp and paper mill secondary sludge was studied in batch assays at 55°C. In total, 12 different pretreatment combinations were compared. Chemical analyses showed that all pretreatments except for HNO3 and ultrasound pretreatments improved the organic matter solubilization. Among the studied pretreatments, hydrothermal (150°C, 10min) pretreatment alone or in combination with enzymatic and/or ultrasound pretreatment had the highest impact on sludge solubilization and methane yield. The increase in methane yield was 31% (from 108ml/g VSoriginal to 141ml/gVSoriginal). In addition, enzymatic pretreatment also improved the methane yields but only when combined with hydrothermal pretreatment at 150°C or ultrasound+hydrothermal pretreatment at 150°C. On the other hand, ultrasound pretreatment did not improve the methane yields while acid and alkaline pretreatments resulted in lower methane yields than control. Improved hydrolysis and higher methane production rates noticed in assays subjected to hydrothermal pretreatment alone or in combination with enzymes and/or ultrasound could make these treatments more attractive in reducing the retention times required during full-scale anaerobic digestion of pulp and paper mill wastewater sludges. © 2013 Elsevier B.V.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Tampere University of Technology, Department of Chemistry and Bioengineering, Urban circular bioeconomy (UrCirBio), Jyväskylän yliopisto, University of Jyväskylä
Contributors: Bayr, S., Kaparaju, P., Rintala, J.
Number of pages: 8
Pages: 479-486
Publication date: 1 May 2013
Peer-reviewed: Yes

Publication information

Journal: Chemical Engineering Journal
Volume: 223
ISSN (Print): 1385-8947
Ratings: 
  • Scopus rating (2013): CiteScore 6.2 SJR 1.597 SNIP 1.908
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all), Chemistry(all), Industrial and Manufacturing Engineering, Environmental Chemistry
Keywords: Anaerobic digestion, Methane yield, Pretreatment, Pulp and paper mill, Secondary sludge

Bibliographical note

Contribution: organisation=keb,FACT1=1<br/>Portfolio EDEND: 2013-11-29<br/>Publisher name: Elsevier BV

Source: researchoutputwizard
Source ID: 1974

Research output: Contribution to journalArticleScientificpeer-review

Shape-dependent plasmonic response and directed self-assembly in a new semiconductor building block, indium-doped cadmium oxide (ICO)

The influence of particle shape on plasmonic response and local electric field strength is well-documented in metallic nanoparticles. Morphologies such as rods, plates, and octahedra are readily synthesized and exhibit drastically different extinction spectra than spherical particles. Despite this fact, the influence of composition and shape on the optical properties of plasmonic semiconductor nanocrystals, in which free electrons result from heavy doping, has not been well-studied. Here, we report the first observation of plasmonic resonance in indium-doped cadmium oxide (ICO) nanocrystals, which exhibit the highest quality factors reported for semiconductor nanocrystals. Furthermore, we are able to independently control the shape and free electron concentration in ICO nanocrystals, allowing for the influence of shape on the optical response of a plasmonic semiconductor to be conclusively demonstrated. The highly uniform particles may be self-assembled into ordered single component and binary nanocrystal superlattices, and in thin films, exhibit negative permittivity in the near infrared (NIR) region, validating their use as a new class of tunable low-loss plasmonic building blocks for 3-D optical metamaterials.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: University of Pennsylvania, Purdue University, Department of Electrical and Systems Engineering
Contributors: Gordon, T. R., Paik, T., Klein, D. R., Naik, G. V., Caglayan, H., Boltasseva, A., Murray, C. B.
Number of pages: 7
Pages: 2857-2863
Publication date: 12 Jun 2013
Peer-reviewed: Yes

Publication information

Journal: Nano Letters
Volume: 13
Issue number: 6
ISSN (Print): 1530-6984
Ratings: 
  • Scopus rating (2013): CiteScore 22.6 SJR 9.081 SNIP 3.355
Original language: English
ASJC Scopus subject areas: Bioengineering, Chemistry(all), Materials Science(all), Condensed Matter Physics, Mechanical Engineering
Keywords: indium-doped cadmium oxide, metamaterials, nanocrystal superlattices, Plasmonics, shape effects, transparent conducting oxide

Bibliographical note

EXT="Caglayan, Humeyra"

Source: Scopus
Source ID: 84879097164

Research output: Contribution to journalArticleScientificpeer-review

Development and characterization of poly(ε-caprolactone) hollow fiber membranes for vascular tissue engineering

The fabrication of tissue-engineered scaffolds for small-caliber blood vessels still remains a challenge. In the present work, we prepared poly(ε-caprolactone) (PCL) hollow fiber (HF) membranes, suitable for small-diameter blood vessel regeneration, by a phase separation spinning technique. The difficulty of processing PCL, a highly elastic material prone to suffer die swelling by extrusion, was overcome by tailoring the dope solution temperature and extrusion flow rate during the spinning procedure. The influence of the composition of the coagulation bath (water, ethanol, isopropanol) on the HF membrane physico-chemical properties (morphology, transport and mechanical properties) and cell attachment and proliferation was studied. The HF membranes fabricated using ethanol as coagulation bath had the most uniform morphology, good mechanical and transport properties and showed human adipose stem cell attachment and proliferation. Therefore, these fibers are promising scaffolds for small-caliber blood vessel regeneration.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Integrated Technologies for Tissue Engineering Research (ITTE), University of Cantabria, University of Twente
Contributors: Diban, N., Haimi, S., Bolhuis-Versteeg, L., Teixeira, S., Miettinen, S., Poot, A., Grijpma, D., Stamatialis, D.
Number of pages: 9
Pages: 29-37
Publication date: 1 Jul 2013
Peer-reviewed: Yes

Publication information

Journal: Journal of Membrane Science
Volume: 438
ISSN (Print): 0376-7388
Ratings: 
  • Scopus rating (2013): CiteScore 8.2 SJR 2.451 SNIP 1.98
Original language: English
ASJC Scopus subject areas: Physical and Theoretical Chemistry, Materials Science(all), Biochemistry, Filtration and Separation
Keywords: Adipose stem cell, Hollow fiber, Phase-inversion, Poly(ε-caprolactone), Vascular regeneration
Source: Scopus
Source ID: 84876440642

Research output: Contribution to journalArticleScientificpeer-review

Mechanisms of acceleration and retardation of water dynamics by ions

There are fundamental and not yet fully resolved questions concerning the impact of solutes, ions in particular, on the structure and dynamics of water, which can be formulated as follows: Are the effects of ions local or long-ranged? Is the action of cations and anions on water cooperative or not? Here, we investigate how the reorientation and hydrogen-bond dynamics of water are affected by ions in dilute and concentrated aqueous salt solutions. By combining simulations and analytic modeling, we first show that ions have a short-ranged influence on the reorientation of individual water molecules and that depending on their interaction strength with water, they may accelerate or slow down water dynamics. A simple additive picture combining the effects of the cations and anions is found to provide a good description in dilute solutions. In concentrated solutions, we show that the average water reorientation time ceases to scale linearly with salt concentration due to overlapping hydration shells and structural rearrangements which reduce the translational displacements induced by hydrogen-bond switches and increase the solution viscosity. This effect is not ion-specific and explains why all concentrated salt solutions slow down water dynamics. Our picture, which is demonstrated to be robust vis-a-vis a change in the force-field, reconciles the seemingly contradictory experimental results obtained by ultrafast infrared and NMR spectroscopies, and suggests that there are no long-ranged cooperative ion effects on the dynamics of individual water molecules in dilute solutions.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Computational Science X (CompX), Columbia University in the City of New York, Lund University, Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, UMR ENS-CNRS-UPMC 8640
Contributors: Stirnemann, G., Wernersson, E., Jungwirth, P., Laage, D.
Number of pages: 8
Pages: 11824-11831
Publication date: 14 Aug 2013
Peer-reviewed: Yes

Publication information

Journal: Journal of the American Chemical Society
Volume: 135
Issue number: 32
ISSN (Print): 0002-7863
Ratings: 
  • Scopus rating (2013): CiteScore 19.3 SJR 5.993 SNIP 2.446
Original language: English
ASJC Scopus subject areas: Chemistry(all), Catalysis, Biochemistry, Colloid and Surface Chemistry
Source: Scopus
Source ID: 84882270662

Research output: Contribution to journalArticleScientificpeer-review

Reversible biofunctionalization of surfaces with a switchable mutant of avidin

Label-free biosensors detect binding of prey molecules (″ analytes″) to immobile bait molecules on the sensing surface. Numerous methods are available for immobilization of bait molecules. A convenient option is binding of biotinylated bait molecules to streptavidin-functionalized surfaces, or to biotinylated surfaces via biotin-avidin-biotin bridges. The goal of this study was to find a rapid method for reversible immobilization of biotinylated bait molecules on biotinylated sensor chips. The task was to establish a biotin-avidin-biotin bridge which was easily cleaved when desired, yet perfectly stable under a wide range of measurement conditions. The problem was solved with the avidin mutant M96H which contains extra histidine residues at the subunit-subunit interfaces. This mutant was bound to a mixed self-assembled monolayer (SAM) containing biotin residues on 20% of the oligo(ethylene glycol)-terminated SAM components. Various biotinylated bait molecules were bound on top of the immobilized avidin mutant. The biotin-avidin-biotin bridge was stable at pH ≥3, and it was insensitive to sodium dodecyl sulfate (SDS) at neutral pH. Only the combination of citric acid (2.5%, pH 2) and SDS (0.25%) caused instantaneous cleavage of the biotin-avidin-biotin bridge. As a consequence, the biotinylated bait molecules could be immobilized and removed as often as desired, the only limit being the time span for reproducible chip function when kept in buffer (2-3 weeks at 25 C). As expected, the high isolectric pH (pI) of the avidin mutant caused nonspecific adsorption of proteins. This problem was solved by acetylation of avidin (to pI <5), or by optimization of SAM formation and passivation with biotin-BSA and BSA.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Multi-scaled biodata analysis and modelling (MultiBAM), Johannes Kepler University, Fimlab Laboratories Ltd, University of Salzburg, University of Basel, University of South Bohemia, Goethe-University Frankfurt
Contributors: Pollheimer, P., Taskinen, B., Scherfler, A., Gusenkov, S., Creus, M., Wiesauer, P., Zauner, D., Schöfberger, W., Schwarzinger, C., Ebner, A., Tampé, R., Stutz, H., Hytönen, V. P., Gruber, H. J.
Number of pages: 13
Pages: 1656-1668
Publication date: 16 Oct 2013
Peer-reviewed: Yes

Publication information

Journal: Bioconjugate Chemistry
Volume: 24
Issue number: 10
ISSN (Print): 1043-1802
Ratings: 
  • Scopus rating (2013): CiteScore 9.1 SJR 2.02 SNIP 1.201
Original language: English
ASJC Scopus subject areas: Biotechnology, Bioengineering, Organic Chemistry, Pharmaceutical Science, Biomedical Engineering, Pharmacology
Source: Scopus
Source ID: 84886070072

Research output: Contribution to journalArticleScientificpeer-review

Magnetophoretic harvesting of oleaginous Chlorella sp. by using biocompatible chitosan/magnetic nanoparticle composites

The consumption of energy and resources such as water in the cultivation and harvesting steps should be minimized to reduce the overall cost of biodiesel production from microalgae. Here we present a biocompatible and rapid magnetophoretic harvesting process of oleaginous microalgae by using chitosan-Fe3O4 nanoparticle composites. Over 99% of microalgae was harvested by using the composites and the external magnetic field without changing the pH of culture medium so that it may be reused for microalgal culture without adverse effect on the cell growth. Depending on the working volume (20-500mL) and the strength of surface magnetic-field (3400-9200G), the process of harvesting microalgae took only 2-5min. The method presented here not only utilizes permanent magnets without additional energy for fast harvesting but also recycles the medium effectively for further cultivation of microalgae, looking ahead to a large scale economic microalgae-based biorefinement.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Urban circular bioeconomy (UrCirBio), Korea Institute of Energy Research, Chungnam National University, Korea District Heating Corp.
Contributors: Lee, K., Lee, S. Y., Na, J. G., Jeon, S. G., Praveenkumar, R., Kim, D. M., Chang, W. S., Oh, Y. K.
Number of pages: 4
Pages: 575-578
Publication date: Dec 2013
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 149
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2013): CiteScore 9 SJR 2.405 SNIP 2.464
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Chitosan, Harvesting, Magnetic nanoparticle, Medium recycling, Microalgae
Source: Scopus
Source ID: 84886601332

Research output: Contribution to journalArticleScientificpeer-review

Direct observation of the collapse of the delocalized excess electron in water

It is generally assumed that the hydrated electron occupies a quasi-spherical cavity surrounded by only a few water molecules in its equilibrated state. However, in the very moment of its generation, before water has had time to respond to the extra charge, it is expected to be significantly larger in size. According to a particle-in-a-box picture, the frequency of its absorption spectrum is a sensitive measure of the initial size of the electronic wavefunction. Here, using transient terahertz spectroscopy, we show that the excess electron initially absorbs in the far-infrared at a frequency for which accompanying ab initio molecular dynamics simulations estimate an initial delocalization length of ≈40 Å. The electron subsequently shrinks due to solvation and thereby leaves the terahertz observation window very quickly, within ≈200 fs.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Computational Science X (CompX), University of Zurich, Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic
Contributors: Savolainen, J., Uhlig, F., Ahmed, S., Hamm, P., Jungwirth, P.
Number of pages: 5
Pages: 697-701
Publication date: 2014
Peer-reviewed: Yes

Publication information

Journal: Nature Chemistry
Volume: 6
Issue number: 8
ISSN (Print): 1755-4330
Ratings: 
  • Scopus rating (2014): CiteScore 32.2 SJR 10.562 SNIP 4.441
Original language: English
ASJC Scopus subject areas: Chemistry(all), Chemical Engineering(all)
Source: Scopus
Source ID: 84904805160

Research output: Contribution to journalArticleScientificpeer-review

Effect of non-rubber components of NR on the carbon nanotube (CNT) localization in SBR/NR blends

Carbon nanotubes (CNTs) are mixed into SBR/NR and SBR/IR blends using a wet mixing process. The phase specific localization of CNTs in rubber blends is predicted theoretically using surface energy data of blend components and determined experimentally by means of the wetting concept. Almost all CNTs are found to be localized in the SBR matrix of SBR/IR blends due to the better affinity of CNTs to SBR than to IR. In contrast, a high CNT loading localized in the NR phase of SBR/NR blends results from the presence of phospholipids in NR. Electrical and mechanical properties of the rubber blends depend strongly on CNT localization. A lower CNT loading in SBR matrix of SBR/NR blends imparts a better wet grip and lower rolling resistance to tire tread compounds.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Engineering materials science and solutions (EMASS), Martin-Luther-University Halle-Wittenberg, Styron Deutschland GmbH, Fraunhofer IWM, Leibniz-Institut für Polymerforschung Dresden E.V., Dau Mot University, Tribhuvan University, Vodafone Department of Mobile Communications Systems
Contributors: Le, H. H., Parsekar, M., Ilisch, S., Henning, S., Das, A., Stöckelhuber, K. W., Beiner, M., Ho, C. A., Adhikari, R., Wießner, S., Heinrich, G., Radusch, H. J.
Number of pages: 14
Pages: 569-582
Publication date: 2014
Peer-reviewed: Yes

Publication information

Journal: Macromolecular Materials and Engineering
Volume: 299
Issue number: 5
ISSN (Print): 1438-7492
Ratings: 
  • Scopus rating (2014): CiteScore 4.7 SJR 1.009 SNIP 1.294
Original language: English
ASJC Scopus subject areas: Organic Chemistry, Materials Chemistry, Polymers and Plastics, Chemical Engineering(all)
Keywords: carbon nanotubes, filler localization, nanocomposites, rubber blends
Source: Scopus
Source ID: 84899990693

Research output: Contribution to journalArticleScientificpeer-review

Fabrication of 3-D nanodimensioned electric double layer capacitor structures using block copolymer templates

The need for materials for high energy storage has led to very significant research in supercapacitor systems. These can exhibit electrical double layer phenomena and capacitances up to hundreds of F/g. Here, we demonstrate a new supercapacitor fabrication methodology based around the microphase separation of PS-b-PMMA which has been used to prepare copper nanoelectrodes of dimension ~13 nm. These structures provide excellent capacitive performance with a maximum specific capacitance of ~836 F/g for a current density of 8.06 A/g at a discharge current as high as 75 mA. The excellent performance is due to a high surface area: volume ratio. We suggest that this highly novel, easily fabricated structure might have a number of important applications.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Frontier Photonics, Materials Chemistry and Analysis Group, University College Cork, Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Tyndall National Institute at National University of Ireland, Cork
Contributors: Rasappa, S., Borah, D., Senthamaraikannan, R., Faulkner, C. C., Holmes, J. D., Morris, M. A.
Number of pages: 7
Pages: 5221-5227
Publication date: 2014
Peer-reviewed: Yes

Publication information

Journal: Journal Nanoscience and Nanotechnology
Volume: 14
Issue number: 7
ISSN (Print): 1533-4880
Ratings: 
  • Scopus rating (2014): CiteScore 2.5 SJR 0.327 SNIP 0.515
Original language: English
ASJC Scopus subject areas: Bioengineering, Chemistry(all), Biomedical Engineering, Materials Science(all), Condensed Matter Physics
Keywords: 3-D Nanostructure, Block Copolymer, Capacitance, Copper Nanowires, PS-b-PMMA, Supercapacitor
Source: Scopus
Source ID: 84903822885

Research output: Contribution to journalArticleScientificpeer-review

Improving the effect of nanoscale barrier coating on BOPP film properties: Influence of substrate contamination, web handling and pretreatments

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Materials Science, Research group: Paper Converting and Packaging, Engineering materials science and solutions (EMASS), Lappeenranta University of Technology, ASTRaL, Miktech Oy, Masaryk Univ, Masaryk University Brno, R&D Ctr Low Cost Plasma & Nanotechnol Surface Mod
Contributors: Lahti, J., Johansson, P., Lahtinen, K., Cameron, D. C., Seppänen, T.
Number of pages: 23
Pages: 1039-1061
Publication date: 2014

Host publication information

Title of host publication: TAPPI PLACE Conference 2014
Volume: 2
Publisher: TAPPI Press
ISBN (Print): 9781510801271
ASJC Scopus subject areas: Materials Science(all), Chemistry(all), Mechanical Engineering, Media Technology, Chemical Engineering(all)
Source: Scopus
Source ID: 84939521131

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Nickel-based HVOF coatings promoting high temperature corrosion resistance of biomass-fired power plant boilers

There are over 1000 biomass boilers in Europe, and the number is increasing due to actions for reducing greenhouse gas emissions. Biomass boilers often experience strong corrosion due to harmful elements in fuels. In biomass burning, detrimental components include especially chlorine, potassium and heavy metals, which can cause chlorine-induced active oxidation or hot corrosion by molten phases even at fairly low temperatures. In order to increase the corrosion resistance of heat exchanger components, either more alloyed steels or protective coatings should be applied. High velocity oxy-fuel (HVOF) sprayed coatings may provide corrosion protection for low alloy tube materials. Three nickel based thermal spray coatings (Ni-24Cr-16.5Mo, Ni-22Cr

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Engineering materials science and solutions (EMASS), VTT Technical Research Centre of Finland
Contributors: Oksa, M., Auerkari, P., Salonen, J., Varis, T.
Number of pages: 10
Pages: 236-245
Publication date: 2014
Peer-reviewed: Yes

Publication information

Journal: Fuel Processing Technology
Volume: 125
ISSN (Print): 0378-3820
Ratings: 
  • Scopus rating (2014): CiteScore 5.9 SJR 1.612 SNIP 2.206
Original language: English
ASJC Scopus subject areas: Fuel Technology, Energy Engineering and Power Technology, Chemical Engineering(all)
Keywords: Biomass combustion, Chlorine induced corrosion, Corrosion protection, High temperature corrosion, HVOF, Thermal spray coating
Source: Scopus
Source ID: 84899841098

Research output: Contribution to journalArticleScientificpeer-review

Repeated use of stable magnetic flocculant for efficient harvest of oleaginous Chlorella sp.

In the present study, a simple magnetic-particle recycling strategy was developed for harvest of the oleaginous microalga Chlorella sp. KR-1. The method entails the flocculation of microalgal cells and bare-Fe3O4 magnetic particles (bMP) by electrostatic attraction and the subsequent recovery of the bMP from the harvested flocs by electrostatic repulsion below and above the isoelectric points (IEP), respectively. For 10 recycles, the bMP showed 94-99% and 90-97% harvest and recovery efficiencies, respectively. Furthermore, neither the use of bMP nor pH adjustment showed any adverse effect on the microalgal cell growth or the co-existing bacterial species, as confirmed from the subsequent medium-recycling test and denaturing gradient gel electrophoresis (DGGE) analysis.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Urban circular bioeconomy (UrCirBio), Korea Institute of Energy Research, Chungnam National University, KAIST
Contributors: Lee, K., Lee, S. Y., Praveenkumar, R., Kim, B., Seo, J. Y., Jeon, S. G., Na, J. G., Park, J. Y., Kim, D. M., Oh, Y. K.
Number of pages: 7
Pages: 284-290
Publication date: 2014
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 167
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2014): CiteScore 9.1 SJR 2.399 SNIP 2.082
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal, Medicine(all)
Keywords: Electrostatic interaction, Harvest, Magnetic particles, Medium recycling, Microalgae
Source: Scopus
Source ID: 84903726411

Research output: Contribution to journalArticleScientificpeer-review

Stearate Modified Zinc-Aluminum Layered Double Hydroxides and Acrylonitrile Butadiene Rubber Nanocomposites

The aim of this investigation is to highlight the potentials of layered double hydroxides (LDH) and to serve as a replacement for zinc oxide and stearic acid from the basic rubber formulation. This will eventually result in about a 10× significant reduction of Zn2+ ion concentration in the final compound. The unique advantage of stearate ion-modified LDH is the delivery of zinc ions to accelerate and stearate ions to activate the vulcanization process. Furthermore, it can also reinforce the rubber matrix by virtue of its layered structure as nanofiller.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Engineering materials science and solutions (EMASS), Vodafone Department of Mobile Communications Systems, Leibniz-Institut für Polymerforschung Dresden E.V., Rubber Technology Centre, Indian Institute of Technology Kharagpur
Contributors: Eshwaran, S. B., Basu, D., Kutlu, B., Leuteritz, A., Wagenknecht, U., Stöckelhuber, K. W., Naskar, K., Das, A., Heinrich, G.
Number of pages: 9
Pages: 65-73
Publication date: Jan 2014
Peer-reviewed: Yes

Publication information

Journal: Polymer-Plastics Technology and Engineering
Volume: 53
Issue number: 1
ISSN (Print): 0360-2559
Ratings: 
  • Scopus rating (2014): CiteScore 3.9 SJR 0.664 SNIP 1.117
Original language: English
ASJC Scopus subject areas: Polymers and Plastics, Materials Science (miscellaneous), Chemical Engineering(all), Materials Chemistry
Keywords: Layered double hydroxide, Nitrile rubber, Sulfur vulcanization, Zinc oxide
Source: Scopus
Source ID: 84891541802

Research output: Contribution to journalArticleScientificpeer-review

Large-area arrays of three-dimensional plasmonic subwavelength-sized structures from azopolymer surface-relief gratings

The field of plasmonics allows for confinement and control of light on the nanoscale. Due to potentially strong resonant interactions that light can have with metal nanoscale structures, metals are a good candidate to tailor interactions with light, e.g., periodic arrays of subwavelength metal structures can support extremely narrow resonances and show enhanced transmission. The field of plasmonics has evolved from using simple geometries to the desire to create complex nanostructures for improved control. The availability of fabrication techniques that provide for complex structures, however, is paired with the seemingly inevitable increase in complexity of fabrication techniques themselves. We present a facile and scalable method for the fabrication of periodic arrays of unique three-dimensional subwavelength-sized structures such as tapered holes and pyramidically shaped subwavelength-sized particles. The procedure consists of holographic inscription of a two-dimensional surface-relief grating in an azobenzene-containing polymer film, evaporative gold deposition and broad-beam ion milling of the relief structure. The method allows the fabrication of highly uniform arrays with tunable lattice parameters and dimensions over large sample areas. The optical response of the fabricated structures is determined experimentally and through simulation, which confirm the unique plasmonic response of the structures. While the proposed fabrication method has clear benefits for plasmonics, it could easily be applied also in other fields, for example by using other coating materials.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Frontier Photonics, Delft University of Technology, COMP Centre of Excellence, Department of Applied Physics, Aalto University, Aalto University
Contributors: Moerland, R. J., Koskela, J. E., Kravchenko, A., Simberg, M., Van Der Vegte, S., Kaivola, M., Priimagi, A., Ras, R. H. A.
Number of pages: 7
Pages: 74-80
Publication date: 1 Jan 2014
Peer-reviewed: Yes

Publication information

Journal: Materials Horizons
Volume: 1
Issue number: 1
ISSN (Print): 2051-6347
Ratings: 
  • Scopus rating (2014): CiteScore 2.8
Original language: English
ASJC Scopus subject areas: Materials Science(all), Mechanics of Materials, Process Chemistry and Technology, Electrical and Electronic Engineering
Source: Scopus
Source ID: 84900804343

Research output: Contribution to journalArticleScientificpeer-review

A 3D Alzheimer's disease culture model and the induction of P21-activated kinase mediated sensing in iPSC derived neurons

The recent progress in stem cell techniques has broadened the horizon for invitro disease modeling. For desired invivo like phenotypes, not only correct cell type specification will be critical, the microenvironmental context will be essential to achieve relevant responses. We demonstrate how a three dimensional (3D) culture of stem cell derived neurons can induce invivo like responses related to Alzheimer's disease, not recapitulated with conventional 2D cultures. To acquire a neural population of cells we differentiated neurons from neuroepithelial stem cells, derived from induced pluripotent stem cells. p21-activated kinase mediated sensing of Aβ oligomers was only possible in the 3D environment. Further, the 3D phenotype showed clear effects on F-actin associated proteins, connected to the disease processes. We propose that the 3D invitro model has higher resemblance to the AD pathology than conventional 2D cultures and could be used in further studies of the disease.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Integrated Technologies for Tissue Engineering Research (ITTE), Karolinska Institutet
Contributors: Zhang, D., Pekkanen-Mattila, M., Shahsavani, M., Falk, A., Teixeira, A. I., Herland, A.
Number of pages: 9
Pages: 1420-1428
Publication date: Feb 2014
Peer-reviewed: Yes

Publication information

Journal: Biomaterials
Volume: 35
Issue number: 5
ISSN (Print): 0142-9612
Ratings: 
  • Scopus rating (2014): CiteScore 15.2 SJR 3.301 SNIP 2.155
Original language: English
ASJC Scopus subject areas: Biomaterials, Bioengineering, Ceramics and Composites, Mechanics of Materials, Biophysics
Keywords: 3D culture, Alzheimer's disease, IPSCs, Mechanotransduction, Neuron, Self-assembling peptide
Source: Scopus
Source ID: 84890173885

Research output: Contribution to journalArticleScientificpeer-review

Structure and barrier properties of human embryonic stem cell-derived retinal pigment epithelial cells are affected by extracellular matrix protein coating

Extracellular matrix (ECM) interactions play a vital role in cell morphology, migration, proliferation, and differentiation of cells. We investigated the role of ECM proteins on the structure and function of human embryonic stem cell-derived retinal pigment epithelial (hESC-RPE) cells during their differentiation and maturation from hESCs into RPE cells in adherent differentiation cultures on several human ECM proteins found in native human Bruch's membrane, namely, collagen I, collagen IV, laminin, fibronectin, and vitronectin, as well as on commercial substrates of xeno-free CELLstart™ and Matrigel™. Cell pigmentation, expression of RPE-specific proteins, fine structure, as well as the production of basal lamina by hESC-RPE on different protein coatings were evaluated after 140 days of differentiation. The integrity of hESC-RPE epithelium and barrier properties on different coatings were investigated by measuring transepithelial resistance. All coatings supported the differentiation of hESC-RPE cells as demonstrated by early onset of cell pigmentation and further maturation to RPE monolayers after enrichment. Mature RPE phenotype was verified by RPE-specific gene and protein expression, correct epithelial polarization, and phagocytic activity. Significant differences were found in the degree of RPE cell pigmentation and tightness of epithelial barrier between different coatings. Further, the thickness of self-assembled basal lamina and secretion of the key ECM proteins found in the basement membrane of the native RPE varied between hESC-RPE cultured on compared protein coatings. In conclusion, this study shows that the cell culture substrate has a major effect on the structure and basal lamina production during the differentiation and maturation of hESC-RPE potentially influencing the success of cell integrations and survival after cell transplantation.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Integrated Technologies for Tissue Engineering Research (ITTE), BioMediTech, Ita-Suomen yliopisto, Tampere University Hospital
Contributors: Sorkio, A., Hongisto, H., Kaarniranta, K., Uusitalo, H., Juuti-Uusitalo, K., Skottman, H.
Number of pages: 13
Pages: 622-634
Publication date: 1 Feb 2014
Peer-reviewed: Yes

Publication information

Journal: Tissue Engineering Part A
Volume: 20
Issue number: 3-4
ISSN (Print): 1937-3341
Ratings: 
  • Scopus rating (2014): CiteScore 7.5 SJR 1.624 SNIP 1.286
Original language: English
ASJC Scopus subject areas: Bioengineering, Biochemistry, Biomaterials, Biomedical Engineering
Source: Scopus
Source ID: 84894176908

Research output: Contribution to journalArticleScientificpeer-review

Assessment of metabolic flux distribution in the thermophilic hydrogen producer Caloramator celer as affected by external pH and hydrogen partial pressure

Background: Caloramator celer is a strict anaerobic, alkalitolerant, thermophilic bacterium capable of converting glucose to hydrogen (H2), carbon dioxide, acetate, ethanol and formate by a mixed acid fermentation. Depending on the growth conditions C. celer can produce H2 at high yields. For a biotechnological exploitation of this bacterium for H2 production it is crucial to understand the factors that regulate carbon and electron fluxes and therefore the final distribution of metabolites to channel the metabolic flux towards the desired product.Results: Combining experimental results from batch fermentations with genome analysis, reconstruction of central carbon metabolism and metabolic flux analysis (MFA), this study shed light on glucose catabolism of the thermophilic alkalitolerant bacterium C. celer. Two innate factors pertaining to culture conditions have been identified to significantly affect the metabolic flux distribution: culture pH and partial pressures of H2 (PH2). Overall, at alkaline to neutral pH the rate of biomass synthesis was maximized, whereas at acidic pH the lower growth rate and the less efficient biomass formation are accompanied with more efficient energy recovery from the substrate indicating high cell maintenance possibly to sustain intracellular pH homeostasis. Higher H2 yields were associated with fermentation at acidic pH as a consequence of the lower synthesis of other reduced by-products such as formate and ethanol. In contrast, PH2 did not affect the growth of C. celer on glucose. At high PH2 the cellular redox state was balanced by rerouting the flow of carbon and electrons to ethanol and formate production allowing unaltered glycolytic flux and growth rate, but resulting in a decreased H2 synthesis.Conclusion: C. celer possesses a flexible fermentative metabolism that allows redistribution of fluxes at key metabolic nodes to simultaneously control redox state and efficiently harvest energy from substrate even under unfavorable conditions (i.e. low pH and high PH2). With the H2 production in mind, acidic pH and low PH2 should be preferred for a high yield-oriented process, while a high productivity-oriented process can be achieved at alkaline pH and high PH2. © 2014 Ciranna et al.; licensee BioMed Central Ltd.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry, Tampere University of Technology, Urban circular bioeconomy (UrCirBio), Lunds Universitet / Lunds Tekniska Högskola, Lund Univ, Lund University, Department of Applied Microbiology
Contributors: Ciranna, A., Pawar, S. S., Santala, V., Karp, M., van Niel, E. W. J.
Publication date: 28 Mar 2014
Peer-reviewed: Yes

Publication information

Journal: Microbial Cell Factories
Volume: 13
Issue number: 1
Article number: 48
ISSN (Print): 1475-2859
Ratings: 
  • Scopus rating (2014): CiteScore 7 SJR 1.757 SNIP 1.508
Original language: English
ASJC Scopus subject areas: Biotechnology, Bioengineering, Applied Microbiology and Biotechnology
Keywords: Biohydrogen production, Caloramator, Ethanol, Fermentation, Formate, Hydrogen tolerance, Metabolic flux analysis, Metabolic shift, Pyruvate node, Redox state

Bibliographical note

Contribution: organisation=keb,FACT1=1<br/>Portfolio EDEND: 2014-04-29<br/>Publisher name: BioMed Central Ltd.

Source: researchoutputwizard
Source ID: 236

Research output: Contribution to journalArticleScientificpeer-review

Light-fuelled transport of large dendrimers and proteins

This work presents a facile water-based supramolecular approach for light-induced surface patterning. The method is based upon azobenzene- functionalized high-molecular weight triazine dendrimers up to generation 9, demonstrating that even very large globular supramolecular complexes can be made to move in response to light. We also demonstrate light-fuelled macroscopic movements in native biomolecules, showing that complexes of apoferritin protein and azobenzene can effectively form light-induced surface patterns. Fundamentally, the results establish that thin films comprising both flexible and rigid globular particles of large diameter can be moved with light, whereas the presented material concepts offer new possibilities for the yet marginally explored biological applications of azobenzene surface patterning.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Frontier Photonics, COMP Centre of Excellence, Department of Applied Physics, Aalto University, Aalto University, Texas Christian University
Contributors: Koskela, J. E., Liljeström, V., Lim, J., Simanek, E. E., Ras, R. H. A., Priimagi, A., Kostiainen, M. A.
Number of pages: 4
Pages: 6850-6853
Publication date: 14 May 2014
Peer-reviewed: Yes

Publication information

Journal: Journal of the American Chemical Society
Volume: 136
Issue number: 19
ISSN (Print): 0002-7863
Ratings: 
  • Scopus rating (2014): CiteScore 20.9 SJR 6.294 SNIP 2.573
Original language: English
ASJC Scopus subject areas: Chemistry(all), Catalysis, Biochemistry, Colloid and Surface Chemistry, Medicine(all)
Source: Scopus
Source ID: 84900818359

Research output: Contribution to journalArticleScientificpeer-review

Bioprocessing of enhanced cellulase production from a mutant of Trichoderma asperellum RCK2011 and its application in hydrolysis of cellulose

A mutant strain of Trichoderma asperellum RCK2011 was developed through UV-irradiation for enhanced cellulase production and lower catabolite repression. The production of FPase, CMCase and β-glucosidase was optimized under solid state fermentation; up to 20 mM of glucose did not inhibit cellulase production. The mutant strain T. asperellum SR1-7 produced FPase (2.2 IU/gds), CMCase (13.2 IU/gds), and β-glucosidase (9.2 IU/gds) under optimized conditions, which is, 1.4, 1.3, 1.5-fold higher than the wild type. The wild as well as mutant strain produced the cellulases at pH range, 4.0-10.0. Saccharification of pretreated corn cob, wheat straw, and sugarcane bagasse by cellulase from mutant strain SR1-7 resulted in release of reducing sugar at the rate of 530.0 mg/g, 290.0 mg/g, and 335.0 mg/g of substrate, respectively; this is 1.6-fold higher than the wild type strain. © 2014 Published by Elsevier Ltd.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry, Tampere University of Technology, Urban circular bioeconomy (UrCirBio), Department of Microbiology, University of Delhi South Campus, Lignocellulose Biotechnology Laboratory
Contributors: Raghuwanshi, S., Deswal, D., Karp, M., Kuhad, R. C.
Number of pages: 7
Pages: 183-189
Publication date: 15 May 2014
Peer-reviewed: Yes

Publication information

Journal: Fuel
Volume: 124
ISSN (Print): 0016-2361
Ratings: 
  • Scopus rating (2014): CiteScore 5.6 SJR 1.634 SNIP 2.29
Original language: English
ASJC Scopus subject areas: Fuel Technology, Energy Engineering and Power Technology, Chemical Engineering(all), Organic Chemistry
Keywords: Alkaline cellulase, Catabolite repression, Saccharification, Solid state fermentation

Bibliographical note

Contribution: organisation=keb,FACT1=1<br/>Portfolio EDEND: 2014-03-15

Source: researchoutputwizard
Source ID: 1327

Research output: Contribution to journalArticleScientificpeer-review

Molecular engineering of avidin and hydrophobin for functional self-assembling interfaces

Control over the functionality of interfaces through biomolecular engineering is a central tool for nanoscale technology as well as many current applications of biology. In this work we designed fusion proteins that combined the surface adhesion and interfacial activity of a hydrophobin-protein together with the high affinity biotin-binding capability of an avidin-protein. We found that an overall architecture that was based on a circularly permuted version of avidin, dual-chain avidin, and hydrophobin gave a highly functional combination. The protein was produced in the filamentous fungus Trichoderma reesei and was efficiently purified using an aqueous two-phase partitioning procedure. The surface adhesive properties were widely different compared to wild-type avidin. Functional characterization showed that the protein assembled on hydrophobic surfaces as a thin layer even at very low concentrations and efficiently bound a biotinylated compound. The work shows how the challenge of creating a fusion protein with proteins that form multimers can be solved by structural design and how protein self-assembly can be used to efficiently functionalize interfaces.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Multi-scaled biodata analysis and modelling (MultiBAM), VTT Technical Research Centre of Finland, Fimlab Laboratories Ltd, Tampere University Hospital, Aalto University
Contributors: Kurppa, K., Hytönen, V. P., Nakari-Setälä, T., Kulomaa, M. S., Linder, M. B.
Number of pages: 8
Pages: 102-109
Publication date: 1 Aug 2014
Peer-reviewed: Yes

Publication information

Journal: Colloids and Surfaces B: Biointerfaces
Volume: 120
ISSN (Print): 0927-7765
Ratings: 
  • Scopus rating (2014): CiteScore 6.8 SJR 1.21 SNIP 1.565
Original language: English
ASJC Scopus subject areas: Surfaces and Interfaces, Biotechnology, Colloid and Surface Chemistry, Physical and Theoretical Chemistry, Medicine(all)
Keywords: Avidin, Biofunctional surface, Hydrophobin, Nanomaterial, Protein engineering
Source: Scopus
Source ID: 84901790623

Research output: Contribution to journalArticleScientificpeer-review

Mixotrophic cultivation of oleaginous Chlorella sp. KR-1 mediated by actual coal-fired flue gas for biodiesel production

Flue gases mainly consist of CO<inf>2</inf> that can be utilized to facilitate microalgal culture for bioenergy production. In the present study, to evaluate the feasibility of the utilization of flue gas from a coal-burning power plant, an indigenous and high-CO<inf>2</inf>-tolerant oleaginous microalga, Chlorella sp. KR-1, was cultivated under mixotrophic conditions, and the results were evaluated. When the culture was mediated by flue gas, highest biomass (0.8 g cells/L·d) and FAME (fatty acid methyl esters) productivity (121 mg/L·d) were achieved in the mixotrophic mode with 5 g/L glucose, 5 mM nitrate, and a flow rate of 0.2 vvm. By contrast, the photoautotrophic cultivation resulted in a lower biomass (0.45 g cells/L·d) and a lower FAME productivity (60.2 mg/L·d). In general, the fatty acid profiles of Chlorella sp. KR-1 revealed meaningful contents (>40 % of saturated and mono-unsaturated fatty acids) under the mixotrophic condition, which enables the obtainment of a better quality of biodiesel than is possible under the autotrophic condition. Conclusively then, it was established that a microalgal culture mediated by flue gas can be improved by adoption of mixotrophic cultivation systems.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Urban circular bioeconomy (UrCirBio), Korea Institute of Energy Research, Pusan National University, Gachon University, Korea Basic Science Institute
Contributors: Praveenkumar, R., Kim, B., Choi, E., Lee, K., Cho, S., Hyun, J. S., Park, J. Y., Lee, Y. C., Lee, H. U., Lee, J. S., Oh, Y. K.
Number of pages: 12
Pages: 2083-2094
Publication date: 12 Sep 2014
Peer-reviewed: Yes

Publication information

Journal: Bioprocess and Biosystems Engineering
Volume: 37
Issue number: 10
ISSN (Print): 1615-7591
Ratings: 
  • Scopus rating (2014): CiteScore 3.2 SJR 0.699 SNIP 0.964
Original language: English
ASJC Scopus subject areas: Biotechnology, Bioengineering, Medicine(all)
Keywords: Biodiesel, Chlorella sp. KR-1, Coal-fired flue gas, Mixotrophic culture
Source: Scopus
Source ID: 84924759723

Research output: Contribution to journalArticleScientificpeer-review

Rapid, Brushless Self-assembly of a PS-b-PDMS Block Copolymer for Nanolithography

Block copolymers (BCP) are highly promising self-assembling precursors for scalable nanolithography. Very regular BCP nanopatterns can be used as on-chip etch masks. The first step in the processing of BCP thin films is usually the chemical modification of the substrate surface, typically by grafting of a brush layer that renders the surface energy neutral relative to the constituent blocks. We provide here a first study on rapid, low temperature self-assembly of PS-. b-PDMS (polystyrene-. block-polydimethylsiloxane) on silicon substrates without a brush layer. We show that it forms line and antidot patterns after short solvo-thermal annealing. Unlike previous reports on this system, low temperature and short annealing time provide self-assembly in homogeneous thin films covering large substrate areas. This on-chip mask was then used for pattern transfer to the underlying silicon substrate. SEM (scanning electron microscope) images reveal silicon nanowires relative to the PDMS patterns of the BCP mask.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Frontier Photonics, Department of Micro and Nanotechnology, Danmarks Tekniske Universitet, DTU Informatik, Center for Nanostructured Graphene, Trinity College Dublin
Contributors: Rasappa, S., Schulte, L., Borah, D., Morris, M. A., Ndoni, S.
Number of pages: 5
Pages: 1-5
Publication date: 1 Oct 2014
Peer-reviewed: Yes

Publication information

Journal: Colloids and Interface Science Communications
Volume: 2
ISSN (Print): 2215-0382
Ratings: 
  • Scopus rating (2014): CiteScore 0.2
Original language: English
ASJC Scopus subject areas: Biotechnology, Colloid and Surface Chemistry, Physical and Theoretical Chemistry, Materials Chemistry, Surfaces, Coatings and Films
Keywords: Aspect ratio, Brushless, Dry etching, Lines and antidots, Pattern transfer, PS-b-PDMS, Self-assembly, Silicon nanostructures, Soft mask template, Solvo-thermal annealing
Source: Scopus
Source ID: 84919650698

Research output: Contribution to journalArticleScientificpeer-review

Improved biomass and lipid production in a mixotrophic culture of Chlorella sp. KR-1 with addition of coal-fired flue-gas

Industrial CO2-rich flue-gases, owing to their eco-toxicity, have yet to be practically exploited for microalgal biomass and lipid production. In this study, various autotrophic and mixotrophic culture modes for an oleaginous microalga, Chlorella sp. KR-1 were compared for the use in actual coal-fired flue-gas. Among the mixotrophic conditions tested, the fed-batch feedings of glucose and the supply of air in dark cycles showed the highest biomass (561mg/Ld) and fatty-acid methyl-ester (168mg/Ld) productivities. This growth condition also resulted in the maximal population of microalgae and the minimal population and types of KR-1-associated-bacterial species as confirmed by particle-volume-distribution and denaturing-gradient-gel-electrophoresis (DGGE) analyses. Furthermore, microalgal lipid produced was assessed, based on its fatty acid profile, to meet key biodiesel standards such as saponification, iodine, and cetane numbers.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Urban circular bioeconomy (UrCirBio), Korea Institute of Energy Research, Gachon University
Contributors: Praveenkumar, R., Kim, B., Choi, E., Lee, K., Park, J. Y., Lee, J. S., Lee, Y. C., Oh, Y. K.
Number of pages: 6
Pages: 500-505
Publication date: 1 Nov 2014
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 171
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2014): CiteScore 9.1 SJR 2.399 SNIP 2.082
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal, Medicine(all)
Keywords: Chlorella sp., Coal-fired flue-gas, Fed-batch, Lipid, Mixotrophic culture
Source: Scopus
Source ID: 84908669116

Research output: Contribution to journalArticleScientificpeer-review

Time-resolved fluorescence methods (IUPAC technical report)

This IUPAC Technical Report describes and compares the currently applied methods for measuring and analyzing time-resolved fluorescence traces using phase-modulation fluorometry as well as pulse fluorometry (direct emission decay measurements, single-photon timing, streak camera measurements, fluorescence upconversion, and optical Kerr gating). The paper starts with a brief description of the basic principles for time and frequency domain fluorescence spectroscopy. The fundamental equations are given, and recommendations for adequate use are emphasized. The up-to-date, commonly employed excitation sources and photodetectors are described in detail. The analysis of time-resolved fluorescence data is discussed. Attention is paid to possible artifacts, and remedies are presented on how to avoid them or to account for them. Finally, fluorescence lifetime standards for the nanosecond and picosecond timescales are collected.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Supramolecular photochemistry, Frontier Photonics, Ecole Normale Superieure de Cachan, Yamagata University, Hasselt University, Humboldt-Universität zu Berlin, CNRS, IRAMIS, LIDYL, Laboratoire Francis Perrin, KU Leuven
Contributors: Lemmetyinen, H., Tkachenko, N. V., Valeur, B., Hotta, J. I., Ameloot, M., Ernsting, N. P., Gustavsson, T., Boens, N.
Number of pages: 30
Pages: 1969-1998
Publication date: 1 Dec 2014
Peer-reviewed: Yes

Publication information

Journal: Pure and Applied Chemistry
Volume: 86
Issue number: 12
ISSN (Print): 0033-4545
Ratings: 
  • Scopus rating (2014): CiteScore 5.3 SJR 1.103 SNIP 1.347
Original language: English
ASJC Scopus subject areas: Chemistry(all), Chemical Engineering(all)
Keywords: Fluorescence spectroscopy, Iupac analytical chemistry division, Iupac organic and biomolecular chemistry division, Iupac physical and biophysical chemistry division, Phase-modulation fluorometry, Pulse fluorometry, Time-resolved fluorescence
Source: Scopus
Source ID: 84928726054

Research output: Contribution to journalArticleScientificpeer-review

Switchavidin: Reversible biotin-avidin-biotin bridges with high affinity and specificity

Switchavidin is a chicken avidin mutant displaying reversible binding to biotin, an improved binding affinity toward conjugated biotin, and low nonspecific binding due to reduced surface charge. These properties make switchavidin an optimal tool in biosensor applications for the reversible immobilization of biotinylated proteins on biotinylated sensor surfaces. Furthermore, switchavidin opens novel possibilities for patterning, purification, and labeling. (Graph Presented).

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Integrated Technologies for Tissue Engineering Research (ITTE), Multi-scaled biodata analysis and modelling (MultiBAM), Fimlab Laboratories Ltd, Johannes Kepler University, Tampere University Hospital
Contributors: Taskinen, B., Zauner, D., Lehtonen, S. I., Koskinen, M., Thomson, C., Kähkönen, N., Kukkurainen, S., Määttä, J. A. E., Ihalainen, T. O., Kulomaa, M. S., Gruber, H. J., Hytönen, V. P.
Number of pages: 11
Pages: 2233-2243
Publication date: 17 Dec 2014
Peer-reviewed: Yes

Publication information

Journal: Bioconjugate Chemistry
Volume: 25
Issue number: 12
ISSN (Print): 1043-1802
Ratings: 
  • Scopus rating (2014): CiteScore 8.7 SJR 1.711 SNIP 1.164
Original language: English
ASJC Scopus subject areas: Biotechnology, Bioengineering, Organic Chemistry, Pharmaceutical Science, Biomedical Engineering, Pharmacology, Medicine(all)
Source: Scopus
Source ID: 84918539954

Research output: Contribution to journalArticleScientificpeer-review

Stimuli-responsive photonic polymer coatings

This feature article focuses on the highlights in the development of photonic polymer coatings that can change their volume or surface topology in a reversible, dynamic fashion when exposed to an external stimulus. Topographic response is established using hydrogels or liquid crystal polymer networks. By changing the surface corrugation in response to light various functional coating properties can be modulated, for instance wettability and/or mechanical friction. The same volume changes in photonic coatings caused by different stimuli lead to changes in light reflection.

General information

Publication status: Published
MoE publication type: A2 Review article in a scientific journal
Organisations: Eindhoven University of Technology
Contributors: Stumpel, J. E., Broer, D. J., Schenning, A. P. H. J.
Number of pages: 10
Pages: 15839-15848
Publication date: 28 Dec 2014
Peer-reviewed: Yes

Publication information

Journal: Chemical Communications
Volume: 50
Issue number: 100
ISSN (Print): 1359-7345
Ratings: 
  • Scopus rating (2014): CiteScore 11.6 SJR 2.692 SNIP 1.427
Original language: English
ASJC Scopus subject areas: Chemistry(all), Catalysis, Ceramics and Composites, Electronic, Optical and Magnetic Materials, Surfaces, Coatings and Films, Materials Chemistry, Metals and Alloys

Bibliographical note

EXT="Stumpel, Jelle"

Source: Scopus
Source ID: 84911908006

Research output: Contribution to journalReview ArticleScientificpeer-review

Characterisation of novel regenerated cellulosic, viscose, and cotton fibres and the dyeing properties of fabrics

There is a global demand for constant increase in the production of textile fibres. Currently, the market for cellulosic fibres is dominated by cotton and viscose fibres. However, new alternative cellulosic fibres are being sought to meet the growing demand. The dyeing properties of novel fibres aiming at the marketplace are among the properties that determine their applicability to textiles. Recently, a novel process for producing cellulosic fibres, the Biocelsol process, has been scaled up so that the spinning of yarn from Biocelsol fibres is now possible. In this study, the reactive dye Levafix CA Blue was applied to cellulosic fabrics made from viscose, cotton, and Biocelsol yarns. The crystalline structure and morphology of the fibres were studied by Fourier transform infrared spectroscopy and field-emission scanning electron microscopy. The crystalline structure and morphology of the Biocelsol fibres resembled those of viscose fibres, but, owing to higher water absorption, the Biocelsol fabric had a higher dye exhaustion. The colour yield of the Biocelsol fabric was 62% and 41% higher than that of cotton and viscose fabrics respectively, suggesting that less dye is needed to gain a shade in Biocelsol fabric than in viscose and cotton fabrics.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Materials Science, Research group: Fibre Materials, Research group: Materials Characterization, Engineering materials science and solutions (EMASS)
Contributors: Kamppuri, T., Vehviläinen, M., Puolakka, A., Honkanen, M., Vippola, M., Rissanen, M.
Number of pages: 7
Pages: 396-402
Publication date: 2015
Peer-reviewed: Yes

Publication information

Journal: Coloration Technology
Volume: 131
Issue number: 5
ISSN (Print): 1472-3581
Ratings: 
  • Scopus rating (2015): CiteScore 2.2 SJR 0.425 SNIP 0.97
Original language: English
ASJC Scopus subject areas: Chemistry (miscellaneous), Chemical Engineering(all), Materials Science (miscellaneous)
Source: Scopus
Source ID: 84941940416

Research output: Contribution to journalArticleScientificpeer-review

Chemolithotrophic denitrification in biofilm reactors

Chemolithotrophic denitrification is an inexpensive and advantageous process for nitrate removal and represents a promising alternative to classical denitrification with organics. Chemolithotrophic denitrifiers are microorganisms able to reduce nitrate and nitrite using inorganic compounds as source of energy. Ferrous iron, sulfur-reduced compounds (e.g. hydrogen sulfide, elemental sulfur and thiosulfate), hydrogen gas, pyrite and arsenite have been used as inorganic electron donors resulting in diverse outcomes. In the last 40years, a large number of engineered systems have been used to maintain chemolithotrophic denitrification and improve rate and efficiency of the process. Among them, biofilm reactors proved to be robust and high-performing technologies. Packed bed reactors are particularly suitable for the removal of low nitrate concentrations, since high retention times are required to complete denitrification. Fluidized bed and membrane biofilm reactors result in the highest denitrification rates (>20kg N-NO<inf>3</inf><sup>-</sup>/m<sup>3</sup>d) when hydrogen gas and sulfur reduced compounds are used as electron donors. Hydrogen gas pressure and current intensity rule the performance of membrane biofilm and biofilm electrode reactors, respectively. Biofouling is the most common and detrimental issue in biofilm reactors. Bed fluidization and hydrogen supply limitation are convenient and effective solutions to mitigate biofouling.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Urban circular bioeconomy (UrCirBio), Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry, Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio
Contributors: Di Capua, F., Papirio, S., Lens, P. N. L., Esposito, G.
Number of pages: 15
Pages: 643-657
Publication date: 2015
Peer-reviewed: Yes
Early online date: 15 Jun 2015

Publication information

Journal: Chemical Engineering Journal
Volume: 280
ISSN (Print): 1385-8947
Ratings: 
  • Scopus rating (2015): CiteScore 8.6 SJR 1.676 SNIP 1.912
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all), Chemistry(all), Industrial and Manufacturing Engineering, Environmental Chemistry
Keywords: Biofilm, Biofilm electrode reactor, Chemolithotrophic denitrification, Fluidized bed reactor, Membrane biofilm reactor, Packed bed reactor

Bibliographical note

AUX=keb,"Di Capua, Francesco"
EXT="Papirio, Stefano"

Source: Scopus
Source ID: 84932636341

Research output: Contribution to journalArticleScientificpeer-review

Coulomb explosion during the early stages of the reaction of alkali metals with water

Alkali metals can react explosively with water and it is textbook knowledge that this vigorous behaviour results from heat release, steam formation and ignition of the hydrogen gas that is produced. Here we suggest that the initial process enabling the alkali metal explosion in water is, however, of a completely different nature. High-speed camera imaging of liquid drops of a sodium/potassium alloy in water reveals submillisecond formation of metal spikes that protrude from the surface of the drop. Molecular dynamics simulations demonstrate that on immersion in water there is an almost immediate release of electrons from the metal surface. The system thus quickly reaches the Rayleigh instability limit, which leads to a 'coulomb explosion' of the alkali metal drop. Consequently, a new metal surface in contact with water is formed, which explains why the reaction does not become self-quenched by its products, but can rather lead to explosive behaviour.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Computational Science X (CompX), Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Technische Universität Braunschweig
Contributors: Mason, P. E., Uhlig, F., Vaněk, V., Buttersack, T., Bauerecker, S., Jungwirth, P.
Number of pages: 5
Pages: 250-254
Publication date: 2015
Peer-reviewed: Yes

Publication information

Journal: Nature Chemistry
Volume: 7
Issue number: 3
ISSN (Print): 1755-4330
Ratings: 
  • Scopus rating (2015): CiteScore 36 SJR 11.144 SNIP 4.588
Original language: English
ASJC Scopus subject areas: Chemistry(all), Chemical Engineering(all)
Source: Scopus
Source ID: 84923338638

Research output: Contribution to journalArticleScientificpeer-review

Efficient preparation of shuffled DNA libraries through recombination (Gateway) cloning

Efficient and robust subcloning is essential for the construction of high-diversity DNA libraries in the field of directed evolution. We have developed a more efficient method for the subcloning of DNAshuffled libraries by employing recombination cloning (Gateway). The Gateway cloning procedure was performed directly after the gene reassembly reaction, without additional purification and amplification steps, thus simplifying the conventional DNA shuffling protocols. Recombination-based cloning, directly from the heterologous reassembly reaction, conserved the high quality of the library and reduced the time required for the library construction. The described method is generally compatible for the construction of DNA-shuffled gene libraries.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Multi-scaled biodata analysis and modelling (MultiBAM), Fimlab Laboratories Ltd, Next Biomed Technologies NBT Oy, Karolinska University Hospital, Tampere University Hospital
Contributors: Lehtonen, S. I., Taskinen, B., Ojala, E., Kukkurainen, S., Rahikainen, R., Riihimäki, T. A., Laitinen, O. H., Kulomaa, M. S., Hytönen, V. P.
Number of pages: 6
Pages: 23-28
Publication date: 2015
Peer-reviewed: Yes

Publication information

Journal: Protein Engineering Design and Selection
Volume: 28
Issue number: 1
ISSN (Print): 1741-0126
Ratings: 
  • Scopus rating (2015): CiteScore 4.9 SJR 1.301 SNIP 0.798
Original language: English
ASJC Scopus subject areas: Biotechnology, Bioengineering, Medicine(all), Biochemistry, Molecular Biology
Keywords: Directed evolution, DNA library, DNA shuffling, Phage display recombination cloning
Source: Scopus
Source ID: 84983121996

Research output: Contribution to journalArticleScientificpeer-review

Enqueˆte de la variabilit´ cycle-`-cycle du NO dans la combustion homog`ne

Cyclic variability of spark ignition engines is recognized as a scatter in the combustion parameter recordings during actual operation in steady state conditions. Combustion variability may occur due to fluctuations in both early flame kernel development and in turbulent flame propagation with an impact on fuel consumption and emissions. In this study, a detailed chemistry model for the prediction of NO formation in homogeneous engine conditions is presented. The Wiebe parameterization is used for the prediction of heat release; then the calculated thermodynamic data are fed into the chemistry model to predict NO evolution at each degree of crank angle. Experimental data obtained from literature studies were used to validate the mean NO levels calculated. Then the model was applied to predict the impact of cyclic variability on mean NO and the amplitude of its variation. The cyclic variability was simulated by introducing random perturbations, which followed a normal distribution, to the Wiebe function parameters. The results of this approach show that the model proposed better predicts mean NO formation than earlier methods. Also, it shows that to the non linear formation rate of NO with temperature, cycle-to-cycle variation leads to higher mean NO emission levels than what one would predict without taking cyclic variation into account.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Urban circular bioeconomy (UrCirBio), Aristotle University of Thessaloniki, Laboratory of Applied Thermodynamics
Contributors: Karvountzis-Kontakiotis, A., Ntziachristos, L.
Number of pages: 13
Pages: 111-123
Publication date: 2015
Peer-reviewed: Yes

Publication information

Journal: OIL AND GAS SCIENCE AND TECHNOLOGY : REVUE DE L'INSTITUT FRANCAIS DU PETROLE
Volume: 70
Issue number: 1
ISSN (Print): 1294-4475
Ratings: 
  • Scopus rating (2015): CiteScore 2.1 SJR 0.361 SNIP 0.733
Original language: French
ASJC Scopus subject areas: Chemical Engineering(all), Fuel Technology, Energy Engineering and Power Technology
Source: Scopus
Source ID: 84924341440

Research output: Contribution to journalArticleScientificpeer-review

Fungal treatment of landfill mining fine fraction to increase its stability and end-use potential

Landfill mining, i.e. extraction, processing, treatment and recovery of landfilled materials, is conducted to prevent pollution and to recover materials and energy from waste (Krook et al., 2012). On average, half of landfilled waste is material resembling soil, i.e. its fine fraction (FF, < 20 mm) (Kaartinen et al., 2013). The end-use potential of the FF is limited due to its organic matter content, a possible presence of harmful contaminants as well as its stability. The aim of this study was to evaluate if fungal treatment stabilises FF and removes organic contaminants thus allowing an end-use of FF as soil-like material. Basidiomycetous fungi were obtained and maintained according to Valentin et al. (2008) prior to experiments and were screened for their potential to grow in FF originally landfilled between 1967 – 1989. Screening experiments and previous experiences with contaminated soil (Valentin et al. 2008) led to the selection of Phanerochaete velutina for fungal treatment experiments, which were carried out at room temperature for 58 days. Two acryl columns (height 600 mm, radius 75 mm) were filled with 1 – 2 cm layer of gravel at the bottom and 5.8 kg of FF on the top as well as 500 mL of tap water. The fungal column was amended with fungal bark inoculum to the middle of the column. Two ports at the bottom of the columns were used to collect leachate and aerate columns with humidified air at 0.1 L/min, respectively. Carbon dioxide (CO2) production was followed during the experiment with gas chromatography. The columns were covered with aluminium foil to stop germination of seeds present in FF. Total solids and volatile solids (VS) were analysed from FF according to standard SFS 3008. Organic contaminants mentioned in criteria for landfilling were analysed from FF in an accredited laboratory. Aerobic stability of FF was determined by the Oxitop method and anaerobic stability of FF was determined as biochemical methane potential. In less than one month, fungal mycelium was observed throughout the FF in the column inoculated with Phanerochaete velutina while no mycelium was observed in the control column. At this stage the experiment was continued in order to allow fungal mycelium to degrade and produce CO2. Concentrations of mineral oils (C10-C40) and organic matter, measured as VS, were higher in FF than in waste that can be placed to landfills. Mineral oil concentrations exceeded Finnish criteria set for contaminated soil. The aerobic stability of FF was high even initially and it did not increase in control or fungal treatments. Fungal treatment reduced organic matter content of FF and reduced mineral oil concentrations, although the criteria set in legislation could not be met in these experiments.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Research group: Industrial Bioengineering and Applied Organic Chemistry, Department of Chemistry and Bioengineering, University of Helsinki, Department of Food and Environmental Sciences
Contributors: Palmroth, M. R. T., Mönkäre, T. J., Steffen, K. T.
Pages: 47
Publication date: 2015

Host publication information

Title of host publication: Book of abstracts of the 6th European Bioremediation Conference
Editors: Kalogerakis, N., Fava, F., Manousaki, E.
Article number: 169
ISBN (Print): 978-960-8475-23-6
ASJC Scopus subject areas: Bioengineering, Geotechnical Engineering and Engineering Geology, Environmental Engineering
Keywords: bioremediation

Bibliographical note

xabstract

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Metals removal and recovery in bioelectrochemical systems: A review

Metal laden wastes and contamination pose a threat to ecosystem well being and human health. Metal containing waste streams are also a valuable resource for recovery of precious and scarce elements. Although biological methods are inexpensive and effective for treating metal wastewaters and in situ bioremediation of metal(loid) contamination, little progress has been made towards metal(loid) recovery. Bioelectrochemical systems are emerging as a new technology platform for removal and recovery of metal ions from metallurgical wastes, process streams and wastewaters. Biodegradation of organic matter by electroactive biofilms at the anode has been successfully coupled to cathodic reduction of metal ions. Until now, leaching of Co(II) from LiCoO<inf>2</inf> particles, and removal of metal ions i.e. Co(III/II), Cr(VI), Cu(II), Hg(II), Ag(I), Se(IV), and Cd(II) from aqueous solutions has been demonstrated. This article reviews the state of art research of bioelectrochemical systems for removal and recovery of metal(loid) ions and pertaining removal mechanisms.

General information

Publication status: Published
MoE publication type: A2 Review article in a scientific journal
Organisations: Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry, Urban circular bioeconomy (UrCirBio), CSIR-Indian Institute of Chemical Technology, Bhabha Atomic Research Centre
Contributors: Nancharaiah, Y. V., Venkata Mohan, S., Lens, P.
Number of pages: 13
Pages: 102-114
Publication date: 2015
Peer-reviewed: Yes
Early online date: 17 Jun 2015

Publication information

Journal: Bioresource Technology
Volume: 195
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2015): CiteScore 9.2 SJR 2.243 SNIP 1.899
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Bioelectrochemical treatment (BET), Biorecovery, Heavy metals, Microbial fuel cells, Wastewater treatment
Source: Scopus
Source ID: 84945442633

Research output: Contribution to journalReview ArticleScientificpeer-review

Multifunctional ultrasmall nanoplatforms for vascular-targeted interstitial photodynamic therapy of brain tumors guided by real-time MRI

Photodynamic therapy (PDT) for brain tumors appears to be complementary to conventional treatments. A number of studies show the major role of the vascular effect in the tumor eradication by PDT. For interstitial PDT (iPDT) of brain tumors guided by real-time imaging, multifunctional nanoparticles consisting of a surface-localized tumor vasculature targeting neuropilin-1 (NRP-1) peptide and encapsulated photosensitizer and magnetic resonance imaging (MRI) contrast agents, have been designed. Nanoplatforms confer photosensitivity to cells and demonstrate a molecular affinity to NRP-1. Intravenous injection into rats bearing intracranial glioma exhibited a dynamic contrast-enhanced MRI for angiogenic endothelial cells lining the neovessels mainly located in the peripheral tumor. By using MRI completed by NRP-1 protein expression of the tumor and brain adjacent to tumor tissues, we checked the selectivity of the nanoparticles. This study represents the first in vivo proof of concept of closed-head iPDT guided by real-time MRI using targeted ultrasmall nanoplatforms.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Frontier Photonics, Université de Lorraine, Lille University Hospital - CHRU, Marcilly-sur-Eure, CHU de Nancy, Claude Bernard-University
Contributors: Bechet, D., Auger, F., Couleaud, P., Marty, E., Ravasi, L., Durieux, N., Bonnet, C., Plénat, F., Frochot, C., Mordon, S., Tillement, O., Vanderesse, R., Lux, F., Perriat, P., Guillemin, F., Barberi-Heyob, M.
Number of pages: 14
Pages: 657-670
Publication date: 2015
Peer-reviewed: Yes

Publication information

Journal: NANOMEDICINE: NANOTECHNOLOGY BIOLOGY AND MEDICINE
Volume: 11
Issue number: 3
ISSN (Print): 1549-9634
Ratings: 
  • Scopus rating (2015): CiteScore 11.4 SJR 1.857 SNIP 1.69
Original language: English
ASJC Scopus subject areas: Molecular Medicine, Bioengineering, Biomedical Engineering, Materials Science(all), Medicine (miscellaneous), Pharmaceutical Science, Medicine(all)
Keywords: Brain tumor, iPDT, Multifunctional nanoplatforms, Real-time MRI, Targeting
Source: Scopus
Source ID: 84933510120

Research output: Contribution to journalArticleScientificpeer-review

Water-responsive dual-coloured photonic polymer coatings based on cholesteric liquid crystals

This work describes a straightforward method to prepare patterned photonic coatings which alter their colour when exposed to water. Various kinds of dual-coloured patterns were made, which become visible or fade away when placed in water. These effects are reversible and can be repeated many times.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Laboratory of Functional Organic Materials and Devices, Eindhoven University of Technology
Contributors: Stumpel, J. E., Broer, D. J., Schenning, A. P. H. J.
Number of pages: 4
Pages: 94650-94653
Publication date: 2015
Peer-reviewed: Yes

Publication information

Journal: RSC Advances
Volume: 5
Issue number: 115
ISSN (Print): 2046-2069
Ratings: 
  • Scopus rating (2015): CiteScore 3.5 SJR 0.947 SNIP 0.838
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all), Chemistry(all)
Source: Scopus
Source ID: 84946926560

Research output: Contribution to journalArticleScientificpeer-review

A comparison of five optical surface topography measurement methods

The results of optical surface topography measurement techniques have been questioned in the past because of possible measurement artifacts due to light penetration into the paper. We compared the topography measurement results from five optical techniques: laser profilometry, shape-from-focus, stripe projection, chromatic sensing, and photometric stereo. These techniques were tested on coated and uncoated papers with a PPS roughness range from 0.7 μm to 7.7 μm. We made the measurement results directly comparable by measuring exactly the same regions on the paper samples and registering the resulting topography maps. We then calculated the point-wise Pearson correlation between the maps at different wavelength bands to obtain quantitative values for the similarity of the measurement results at different structure sizes. The correspondences between the measured topography maps were also examined through multivariate linear regression and roughness indices evaluated at two different structure sizes. For rougher grades like office paper or sack paper, the topography measurements from the five measurement techniques showed corresponding results. For a moderately smooth lightweight coated (LWC) paper, the measured topographies agreed to some degree, and for smooth supercalendered (SC) and woodfree coated (WFC) papers, the agreement was poor. From the available data, it is impossible to tell which of the measurement techniques delivers the true surface topography of smooth papers.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Automation Science and Engineering, Field robotics for efficient work sites (FIRE), Graz University of Technology
Contributors: Mettänen, M., Hirn, U.
Number of pages: 12
Pages: 27-38
Publication date: 1 Jan 2015
Peer-reviewed: Yes

Publication information

Journal: TAPPI Journal
Volume: 14
Issue number: 1
ISSN (Print): 0734-1415
Ratings: 
  • Scopus rating (2015): SJR 0.44 SNIP 0.718
Original language: English
ASJC Scopus subject areas: Media Technology, Chemical Engineering(all), Chemistry(all), Mechanical Engineering, Materials Science(all)
Electronic versions: 
Source: Scopus
Source ID: 84923164333

Research output: Contribution to journalArticleScientificpeer-review

Perfluoro-1,1′-biphenyl and perfluoronaphthalene and their derivatives as π-acceptors for anions

Addition of anions to perfluorinated 1,1′-biphenyl 1 or naphthalene 2 results in a shift of the 19F NMR signals. However, any specific interaction cannot be assigned to this effect. In order to study the interaction in more detail, the salt derivatives 3 and 4 were prepared and studied by single crystal X-ray diffraction revealing weak anion-π interactions in the solid state.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, University of Jyväskylä, Institut für Organische Chemie, RWTH Aachen
Contributors: Yi, H., Albrecht, M., Valkonen, A., Rissanen, K.
Number of pages: 4
Pages: 746-749
Publication date: 1 Jan 2015
Peer-reviewed: Yes

Publication information

Journal: New Journal of Chemistry
Volume: 39
Issue number: 1
ISSN (Print): 1144-0546
Ratings: 
  • Scopus rating (2015): CiteScore 4 SJR 0.935 SNIP 0.825
Original language: English
ASJC Scopus subject areas: Chemistry(all), Catalysis, Materials Chemistry
Source: Scopus
Source ID: 84919782132

Research output: Contribution to journalArticleScientificpeer-review

Oxidation half-reaction of aqueous nucleosides and nucleotides via photoelectron spectroscopy augmented by ab initio calculations

Oxidative damage to DNA and hole transport between nucleobases in oxidized DNA are important processes in lesion formation for which surprisingly poor thermodynamic data exist, the relative ease of oxidizing the four nucleobases being one such example. Theoretical simulations of radiation damage and charge transport in DNA depend on accurate values for vertical ionization energies (VIEs), reorganization energies, and standard reduction potentials. Liquid-jet photoelectron spectroscopy can be used to directly study the oxidation half-reaction. The VIEs of nucleic acid building blocks are measured in their native buffered aqueous environment. The experimental investigation of purine and pyrimidine nucleotides, nucleosides, pentose sugars, and inorganic phosphate demonstrates that photoelectron spectra of nucleotides arise as a spectral sum over their individual chemical components; that is, the electronic interactions between each component are effectively screened from one another by water. Electronic structure theory affords the assignment of the lowest energy photoelectron band in all investigated nucleosides and nucleotides to a single ionizing transition centered solely on the nucleobase. Thus, combining the measured VIEs with theoretically determined reorganization energies allows for the spectroscopic determination of the one-electron redox potentials that have been difficult to establish via electrochemistry.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Computational Science X (CompX), University of Southern California, Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Max-Planck-Institut für Dynamik und Selbstorganisation, Department of Physical Chemistry, Helmholtz Center Berlin
Contributors: Schroeder, C. A., Pluharová, E., Seidel, R., Schroeder, W. P., Faubel, M., Slavíçek, P., Winter, B., Jungwirth, P., Bradforth, S. E.
Number of pages: 9
Pages: 201-209
Publication date: 14 Jan 2015
Peer-reviewed: Yes

Publication information

Journal: Journal of the American Chemical Society
Volume: 137
Issue number: 1
ISSN (Print): 0002-7863
Ratings: 
  • Scopus rating (2015): CiteScore 22.4 SJR 6.775 SNIP 2.6
Original language: English
ASJC Scopus subject areas: Catalysis, Chemistry(all), Biochemistry, Colloid and Surface Chemistry
Source: Scopus
Source ID: 84921038760

Research output: Contribution to journalArticleScientificpeer-review

Second-Harmonic Generation from Metal Nanoparticles: Resonance Enhancement versus Particle Geometry

We demonstrate that optical second-harmonic generation (SHG) from arrays of noncentrosymmetric gold nanoparticles depends essentially on particle geometry. We prepare nanoparticles with different geometrical shapes (L and T) but similar wavelengths for the polarization-dependent plasmon resonances. In contrast to recent interpretations emphasizing resonances at the fundamental frequency, the T shape leads to stronger SHG when only one, instead of both, polarization component of the fundamental field is resonant. This is explained by the character of plasmon oscillations supported by the two shapes. Our numerical simulations for both linear and second-order responses display unprecedented agreement with measurements.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Physics, Research area: Optics, Research group: Nonlinear Optics, Frontier Photonics, Institute of Photonics, Univ Eastern Finland, University of Eastern Finland, Sch Pharm
Contributors: Czaplicki, R., Mäkitalo, J., Siikanen, R., Husu, H., Lehtolahti, J., Kuittinen, M., Kauranen, M.
Number of pages: 5
Pages: 530-534
Publication date: 14 Jan 2015
Peer-reviewed: Yes
Early online date: 18 Dec 2014

Publication information

Journal: Nano Letters
Volume: 15
Issue number: 1
ISSN (Print): 1530-6984
Ratings: 
  • Scopus rating (2015): CiteScore 22.9 SJR 8.359 SNIP 3.071
Original language: English
ASJC Scopus subject areas: Condensed Matter Physics, Bioengineering, Chemistry(all), Materials Science(all), Mechanical Engineering
Keywords: Metal nanoparticles, nonlinear optics, plasmonic resonances, second-harmonic generation
Source: WOS
Source ID: 000348086100083

Research output: Contribution to journalArticleScientificpeer-review

Second-harmonic generation imaging of semiconductor nanowires with focused vector beams

We use second-harmonic generation (SHG) with focused vector beams to investigate individual vertically aligned GaAs nanowires. Our results provide direct evidence that SHG from oriented nanowires is mainly driven by the longitudinal field along the nanowire growth axis. Consequently, focused radial polarization provides a superior tool to characterize such nanowires compared to linear polarization, also allowing this possibility in the native growth environment. We model our experiments by describing the SHG process for zinc-blende structure and dipolar bulk nonlinearity.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Physics, Research area: Optics, Research group: Nonlinear Optics, Tampere University of Technology, Frontier Photonics, Aalto University, Department of Micro- and Nanosciences, Aalto University, Department of Applied Physics and Nanomicroscopy Center
Contributors: Bautista, G., Mäkitalo, J., Chen, Y., Dhaka, V., Grasso, M., Karvonen, L., Jiang, H., Huttunen, M. J., Huhtio, T., Lipsanen, H., Kauranen, M.
Number of pages: 6
Pages: 1564-1569
Publication date: 6 Feb 2015
Peer-reviewed: Yes

Publication information

Journal: Nano Letters
Volume: 15
Issue number: 3
ISSN (Print): 1530-6984
Ratings: 
  • Scopus rating (2015): CiteScore 22.9 SJR 8.359 SNIP 3.071
Original language: English
ASJC Scopus subject areas: Condensed Matter Physics, Bioengineering, Chemistry(all), Materials Science(all), Mechanical Engineering
Keywords: modeling, nonlinear imaging, radial polarization, Second-harmonic generation, semiconductor

Bibliographical note

AUX=fys,"Grasso, Marco"
EXT="Dhaka, Veer"
EXT="Huttunen, Mikko J."

Source: Scopus
Source ID: 84924595561

Research output: Contribution to journalArticleScientificpeer-review

Fluidized-bed denitrification of mining water tolerates high nickel concentrations

This study revealed that fluidized-bed denitrifying cultures tolerated soluble Ni concentrations up to 500mg/L at 7-8 and 22°C. From 10 to 40mg/L of feed Ni, denitrification resulted in complete nitrate and nitrite removal. The concomitant reduction of 30mg/L of sulfate produced 10mg/L of sulfide that precipitated nickel, resulting in soluble effluent Ni below 22mg/L. At this stage, Dechloromonas species were the dominant denitrifying bacteria. From 60 to 500mg/L of feed Ni, nickel remained in solution due to the inhibition of sulfate reduction. At soluble 60mg/L of Ni, denitrification was partially inhibited prior to recover after 34days of enrichment by other Ni-tolerant species (including Delftia, Zoogloea and Azospira) that supported Dechloromonas. Subsequently, the FBR cultures completely removed nitrate even at 500mg/L of Ni. Visual Minteq speciation model predicted the formation of NiS, NiCO3 and Ni3(PO4)2, whilst only Ni3(PO4)2 was detected by XRD.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry, Urban circular bioeconomy (UrCirBio), Université Paris-Est, Laboratoire Géomatériaux et Environnement (EA 4508), UPEM
Contributors: Zou, G., Papirio, S., van Hullebusch, E. D., Puhakka, J. A.
Number of pages: 7
Pages: 284-290
Publication date: 1 Mar 2015
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 179
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2015): CiteScore 9.2 SJR 2.243 SNIP 1.899
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Denitrification, Denitrifying communities, Fluidized-bed reactor, Nickel, X-ray diffraction
Source: Scopus
Source ID: 84919934975

Research output: Contribution to journalArticleScientificpeer-review

Multi-stable dynamics of the non-adiabatic repressilator

The assumption of the fast binding of transcription factors (TFs) to promoters is a typical point in studies of synthetic genetic circuits functioning in bacteria. Although the assumption is effective for simplifying the models, it becomes questionable in the light of in vivo measurements of the times TF spends searching for its cognate DNA sites. We investigated the dynamics of the full idealized model of the paradigmatic genetic oscillator, the repressilator, using deterministic mathematical modelling and stochastic simulations. We found (using experimentally approved parameter values) that decreases in the TF binding rate changes the type of transition between steady state and oscillation. As a result, this gives rise to the hysteresis region in the parameter space, where both the steady state and the oscillation coexist. We further show that the hysteresis is persistent over a considerable range of the parameter values, but the presence of the oscillations is limited by the low rate of TF dimer degradation. Finally, the stochastic simulation of the model confirms the hysteresis with switching between the two attractors, resulting in highly skewed period distributions. Moreover, intrinsic noise stipulates trains of large-amplitude modulations around the stable steady state outside the hysteresis region, which makes the period distributions bimodal.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Mathematics, Research group: MAT Inverse Problems, Mathematical modelling with wide societal impact (MathImpact), Department of Theoretical Physics, Lebedev Physical Institution
Contributors: Potapov, I., Zhurov, B., Volkov, E.
Publication date: 6 Mar 2015
Peer-reviewed: Yes

Publication information

Journal: Journal of the Royal Society. Interface
Volume: 12
Issue number: 104
Article number: 20141315
ISSN (Print): 1742-5689
Ratings: 
  • Scopus rating (2015): CiteScore 7.5 SJR 1.823 SNIP 1.554
Original language: English
ASJC Scopus subject areas: Biophysics, Biotechnology, Bioengineering, Biomedical Engineering, Biomaterials, Biochemistry
Keywords: Adiabatic, Bimodality, Genetic oscillator, Hysteresis, Multi-stability
Source: Scopus
Source ID: 84923240824

Research output: Contribution to journalArticleScientificpeer-review

Workplace performance of a loose-fitting powered air purifying respirator during nanoparticle synthesis

Nanoparticle (particles with diameter ≤100 nm) exposure is recognized as a potentially harmful size fraction for pulmonary particle exposure. During nanoparticle synthesis, the number concentrations in the process room may exceed 10 × 10<sup>6</sup> cm<sup>−3</sup>. During such conditions, it is essential that the occupants in the room wear highly reliable high-performance respirators to prevent inhalation exposure. Here we have studied the in-use program protection factor (PPF) of loose-fitting powered air purifying respirators, while workers were coating components with TiO<inf>2</inf> or Cu<inf>x</inf>O<inf>y</inf> nanoparticles under a hood using a liquid flame spray process. The PPF was measured using condensation particle counters, an electrical low pressure impactor, and diffusion chargers. The room particle concentrations varied from 4 × 10<sup>6</sup> to 40 × 10<sup>6</sup> cm<sup>−3</sup>, and the count median aerodynamic diameter ranged from 32 to 180 nm. Concentrations inside the respirator varied from 0.7 to 7.2 cm<sup>−3</sup>. However, on average, tidal breathing was assumed to increase the respirator concentration by 2.3 cm<sup>−3</sup>. The derived PPF exceeded 1.1 × 10<sup>6</sup>, which is more than 40 × 10<sup>3</sup> times the respirator assigned protection factor. We were unable to measure clear differences in the PPF of respirators with old and new filters, among two male and one female user, or assess most penetrating particle size. This study shows that the loose-fitting powered air purifying respirator provides very efficient protection against nanoparticle inhalation exposure if used properly.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Physics, Research group: Aerosol Synthesis, National Research Centre for the Working Environment, Finnish Institute of Occupational Health, Helsinki University, TNO
Contributors: Koivisto, A. J., Aromaa, M., Koponen, I. K., Fransman, W., Jensen, K. A., Mäkelä, J. M., Hämeri, K. J.
Publication date: 9 Apr 2015
Peer-reviewed: Yes

Publication information

Journal: Journal of Nanoparticle Research
Volume: 17
Issue number: 4
ISSN (Print): 1388-0764
Ratings: 
  • Scopus rating (2015): CiteScore 3.8 SJR 0.568 SNIP 0.725
Original language: English
ASJC Scopus subject areas: Atomic and Molecular Physics, and Optics, Condensed Matter Physics, Modelling and Simulation, Chemistry(all), Materials Science(all), Bioengineering
Keywords: Aerosol, Air purifying respirator, Filtration, Occupational safety, Protection factor, Respirator performance

Bibliographical note

EXT="Koivisto, Antti J."

Source: Scopus
Source ID: 84927730047

Research output: Contribution to journalArticleScientificpeer-review

'miSimBa' - A simulator of synthetic time-lapsed microscopy images of bacterial cells

Escherichia coli is a model organism for the study of multiple biological processes, including gene expression and cellular aging. Recently, these studies started to rely on temporal single cell imaging. To support these efforts, available automated image analysis methods should be improved. One important step is their validation. Ideally, the 'ground truth' of the images should be known, which is possible only in synthetic images. To simulate artificial images of E. coli cells, we are developing the 'miSimBa' tool (Microscopy Image Simulator of Bacterial Cells). 'miSimBa' simulates images that reproduce the spatial and temporal bacterial organization by modelling realistically cell morphology (shape, size and spatial arrangement), cell growth and division, cell motility and some internal functions and intracellular structures, namely, the nucleoid. This tool also incorporates image acquisition parameters that simulate illumination and the primary sources of noise.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Research group: Laboratory of Biosystem Dynamics-LBD, Department of Signal Processing, Multi-scaled biodata analysis and modelling (MultiBAM), Universidade de Lisboa, CA3, UNINOVA - Centre of Technology and Systems, Faculdade de Ciências e Tecnologia da Universidade Nova
Contributors: Martins, L., Fonseca, J., Ribeiro, A.
Publication date: 17 Apr 2015

Host publication information

Title of host publication: Proceedings - 2015 IEEE 4th Portuguese Meeting on Bioengineering, ENBENG 2015
Publisher: The Institute of Electrical and Electronics Engineers, Inc.
Article number: 7088854
ISBN (Print): 9781479982691
ASJC Scopus subject areas: Bioengineering
Keywords: Microscopy imaging, Synthetic image simulation, Time-lapse simulation
Source: Scopus
Source ID: 84929250520

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Biomimetic collagen I and IV double layer Langmuir-Schaefer films asmicroenvironment for human pluripotent stem cell derived retinal pigment epithelial cells

The environmental cues received by the cells from synthetic substrates invitro are very different from those they receive invivo. In this study, we applied the Langmuir-Schaefer (LS) deposition, a variant of Langmuir-Blodgett technique, to fabricate a biomimetic microenvironment mimicking the structure and organization of native Bruch's membrane for the production of the functional human embryonic stem cell derived retinal pigment epithelial (hESC-RPE) cells. Surface pressure-area isotherms were measured simultaneously with Brewster angle microscopy to investigate the self-assembly of human collagens type I and IV on air-subphase interface. Furthermore, the structure of the prepared collagen LS films was characterized with scanning electron microscopy, atomic force microscopy, surface plasmon resonance measurements and immunofluorescent staining. The integrity of hESC-RPE on double layer LS films was investigated by measuring transepithelial resistance and permeability of small molecular weight substance. Maturation and functionality of hESC-RPE cells on double layer collagen LS films was further assessed by RPE-specific gene and protein expression, growth factor secretion, and phagocytic activity. Here, we demonstrated that the prepared collagen LS films have layered structure with oriented fibers corresponding to architecture of the uppermost layers of Bruch's membrane and result in increased barrier properties and functionality of hESC-RPE cells as compared to the commonly used dip-coated controls.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Supramolecular photochemistry, Tampere University of Technology, BioMediTech, Frontier Photonics, Integrated Technologies for Tissue Engineering Research (ITTE), Aalto University, BioMediTech, Univ Tampere, University of Tampere, BioMediTech, BMT FM5, Centre for Drug Research, Faculty of Pharmacy, Helsinki University, Department of Forest Products Technology, School of Chemical Technology, Division of Biopharmaceutical Sciences
Contributors: Sorkio, A. E., Vuorimaa-Laukkanen, E. P., Hakola, H. M., Liang, H., Ujula, T. A., Valle-Delgado, J. J., Österberg, M., Yliperttula, M. L., Skottman, H.
Number of pages: 13
Pages: 257-269
Publication date: 1 May 2015
Peer-reviewed: Yes

Publication information

Journal: Biomaterials
Volume: 51
ISSN (Print): 0142-9612
Ratings: 
  • Scopus rating (2015): CiteScore 16.2 SJR 3.404 SNIP 2.013
Original language: English
ASJC Scopus subject areas: Biomaterials, Bioengineering, Ceramics and Composites, Mechanics of Materials, Biophysics
Keywords: Biomimetic material, Collagen structure, Human embryonic stem cell, Langmuir Blodgett film, Retina, Retinal pigment epithelial cell
Source: WOS
Source ID: 000351796700025

Research output: Contribution to journalArticleScientificpeer-review

A facile route to synthesis of S-doped TiO2 nanoparticles for photocatalytic activity

There is always a market for cost effective methods of pollution degradation and one of the best areas to keep costs down is through synthesis techniques. This paper provides a simple technique to synthesise porous TiO2 nanoparticles with increased surface area through a scaffold template technique. Their photocatalytic activity is enhanced by incorporating sulphur as a dopant and were validated by analysing the degradation of malachite green (MG). The materials were doped at a molar ratio of 100:1 (Ti:S) and calcined at different temperatures to adjust the anatase/rutile content. Detailed characterisation of the materials was undertaken using XRD, BET, XPS, TEM and FTIR. The nanoparticles displayed a microporous structure and had an increased surface area of 115 m2 g-1 which was reduced by doping and temperature induced phase transformation. Photocatalytic testing showed that the doped materials calcined at 700 °C preformed the best in. It was observed that 20 mg l-1 of MG was decomposed in 30 min using a 40 W UV bulb at pH 9 and the results surpassed those achieved by the commercial catalyst P25 which was also tested for comparison.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Frontier Photonics, Trinity College Dublin, University College Cork, Materials Chemistry and Analysis Group, Centre for Research on Adaptive Nanostructures and Nanodevices
Contributors: McManamon, C., O'Connell, J., Delaney, P., Rasappa, S., Holmes, J. D., Morris, M. A.
Pages: 51-57!
Publication date: 30 May 2015
Peer-reviewed: Yes

Publication information

Journal: Journal of Molecular Catalysis A: Chemical
Volume: 406
ISSN (Print): 1381-1169
Ratings: 
  • Scopus rating (2015): CiteScore 6.1 SJR 1.052 SNIP 1.262
Original language: English
ASJC Scopus subject areas: Catalysis, Physical and Theoretical Chemistry, Process Chemistry and Technology
Keywords: Band gap, Photocatalysis, S-doped, TiO<inf>2</inf>
Source: Scopus
Source ID: 84930210395

Research output: Contribution to journalArticleScientificpeer-review

Catalytic effect of Ca and K on CO2 gasification of spruce wood char

Gasification is one route to produce chemicals and liquid fuels from biomass. The gasification of the char is catalyzed by alkali and alkaline earth metals in the biomass. In this work the catalytic effect of calcium (Ca) and potassium (K) on CO2 gasification of spruce wood was studied using a thermo gravimetric analyzer (TGA). The ash-forming elements were first removed from the wood using an acid leaching method. Then, various concentrations of K and Ca were absorbed to the wood by ion-exchange to carboxylic and phenolic groups, impregnation of K2CO3 or physically mixing of CaC2O4. The prepared spruce samples were placed in a mesh holder and gasified in the TGA at 850°C in 100% CO2. The results demonstrate that the gasification rate of the char increased linearly with an increase in the concentration of Ca or K. Crystalline CaC2O4 distributed only at the surface of the wood particles resulted in low catalytic activity. The catalytic activity of Ca was higher than K in the beginning of char gasification but the catalytic effect of Ca decreased earlier than the catalytic effect of potassium. Further, the char structure was investigated by SEM-EDX. The SEM analysis from interrupted gasification experiments showed the formation of CaCO3 and K2CO3 layer on the char surface. By adding corresponding levels of Ca and K as the original spruce to the acid washed sample, a similar gasification reactivity was obtained at 850 °C.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Urban circular bioeconomy (UrCirBio), Abo Akademi University, Åbo Akademi University, University of Jyväskylä, Process Chemistry Center, VTT Technical Research Centre of Finland
Contributors: Perander, M., DeMartini, N., Brink, A., Kramb, J., Karlström, O., Hemming, J., Moilanen, A., Konttinen, J., Hupa, M.
Number of pages: 9
Pages: 464-472
Publication date: 15 Jun 2015
Peer-reviewed: Yes

Publication information

Journal: Fuel
Volume: 150
ISSN (Print): 0016-2361
Ratings: 
  • Scopus rating (2015): CiteScore 6.9 SJR 1.781 SNIP 2.111
Original language: English
ASJC Scopus subject areas: Fuel Technology, Energy Engineering and Power Technology, Chemical Engineering(all), Organic Chemistry
Keywords: Biomass, Calcium, Char reactivity, CO, Gasification, Potassium

Bibliographical note

EXT="Kramb, J."

Source: Scopus
Source ID: 84924100908

Research output: Contribution to journalArticleScientificpeer-review

The influence of SrO and CaO in silicate and phosphate bioactive glasses on human gingival fibroblasts

In this paper, we investigate the effect of substituting SrO for CaO in silicate and phosphate bioactive glasses on the human gingival fibroblast activity. In both materials the presence of SrO led to the formation of a CaP layer with partial Sr substitution for Ca. The layer at the surface of the silicate glass consisted of HAP whereas at the phosphate glasses it was close to the DCPD composition. In silicate glasses, SrO gave a faster initial dissolution and a thinner reaction layer probably allowing for a continuous ion release into the solution. In phosphate glasses, SrO decreased the dissolution process and gave a more strongly bonded reaction layer. Overall, the SrO-containing silicate glass led to a slight enhancement in the activity of the gingival fibroblasts cells when compared to the SrO-free reference glass, S53P4. The cell activity decreased up to 3 days of culturing for all phosphate glasses containing SrO. Whereas culturing together with the SrO-free phosphate glass led to complete cell death at 7 days. The glasses containing SrO showed rapid cell proliferation and growth between 7 and 14 days, reaching similar activity than glass S53P4. The addition of SrO in both silicate and phosphate glasses was assumed beneficial for proliferation and growth of human gingival fibroblasts due to Sr incorporation in the reaction layer at the glass surface and released in the cell culture medium.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Electronics and Communications Engineering, Research group: Biomaterials and Tissue Engineering Group, Integrated Technologies for Tissue Engineering Research (ITTE), Turun Yliopisto/Turun Biomateriaalikeskus, Åbo Akademi University, Process Chemistry Centre, University of Turku, Department of Prosthetic Dentistry, Clinic of Oral Diseases, Turku University Central Hospital
Contributors: Massera, J., Kokkari, A., Närhi, T., Hupa, L.
Publication date: 25 Jun 2015
Peer-reviewed: Yes

Publication information

Journal: Journal of Materials Science: Materials in Medicine
Volume: 26
Issue number: 6
Article number: 196
ISSN (Print): 0957-4530
Ratings: 
  • Scopus rating (2015): CiteScore 4.8 SJR 0.786 SNIP 1.018
Original language: English
ASJC Scopus subject areas: Biophysics, Biomaterials, Bioengineering, Biomedical Engineering
Source: Scopus
Source ID: 84935013205

Research output: Contribution to journalArticleScientificpeer-review

Lipid production by eukaryotic microorganisms isolated from palm oil mill effluent

Microbial oil production combined with wastewater management is one option for a more sustainable future. Micrographs of microbial cultures enriched from palm oil mill effluent (POME) showed lipid inclusion in the eukaryotic cells, indicating the cells can accumulate lipids. However, enriching the culture did not increase the total lipids. Therefore, eukaryotic microorganisms were isolated from POME to investigate whether these microorganisms are potential lipid producers. Four strains were isolated, and their lipid synthesis capabilities were compared with known oleaginous yeasts in a synthetic oil-free medium. Two strains (identified as Galactomyces geotrichum and Graphium penicillioides) had the potential to accumulate lipid accumulation based on the increase in triacylglycerol content. G. penicillioides was the most promising strain for lipid production as this strain accumulated more lipids than the well-known oleaginous yeast Cryptococcus curvatus (29.1 ± 3.0. wt% vs. 20.2 ± 2.9. wt%). To our knowledge, oil synthesis and accumulation by G. penicillioides have not previously been reported.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry, Urban circular bioeconomy (UrCirBio), National Cheng Kung University, Center of Bioscience and Biotechnology, Research Center for Energy Technology and Strategy, Neste Oil Oyj
Contributors: Marjakangas, J. M., Lakaniemi, A. M., Koskinen, P. E. P., Chang, J. S., Puhakka, J. A.
Number of pages: 7
Pages: 48-54
Publication date: 5 Jul 2015
Peer-reviewed: Yes

Publication information

Journal: Biochemical Engineering Journal
Volume: 99
ISSN (Print): 1369-703X
Ratings: 
  • Scopus rating (2015): CiteScore 4.6 SJR 0.952 SNIP 1.075
Original language: English
ASJC Scopus subject areas: Biotechnology, Bioengineering, Biomedical Engineering, Environmental Engineering
Keywords: Filamentous fungi, Lipid accumulation, Microbial growth, Palm oil mill effluent, Physiology, Yeast

Bibliographical note

EXT="Koskinen, Perttu E. P."

Source: Scopus
Source ID: 84924943977

Research output: Contribution to journalArticleScientificpeer-review

Lithography-free oxide patterns as templates for self-catalyzed growth of highly uniform GaAs nanowires on Si(111)

We report self-catalyzed growth of GaAs nanowires (NWs) on Si/SiO<inf>x</inf> patterns fabricated by a lithography-free method. The patterns are defined using droplet epitaxy of GaAs nanocrystals, spontaneous oxidation, and thermal annealing. We investigate the influence of the size and density of the nucleation sites on the NW growth process and show that this approach enables the fabrication of highly uniform GaAs NWs with controllable density. The pattern fabrication and NW growth process are studied and discussed in relation to the surface morphology and chemical properties of the Si/SiO<inf>x</inf> patterns. Furthermore, the optical quality of the NWs is investigated by photoluminescence experiments performed for GaAs-AlGaAs core-shell NWs.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Optoelectronics Research Centre, Research group: Semiconductor Technology and Applications, Augmented Human Activities (AHA), Frontier Photonics, Department of Physics and Astronomy, University of Turku, University of Turku
Contributors: Hakkarainen, T. V., Schramm, A., Mäkelä, J., Laukkanen, P., Guina, M.
Publication date: 18 Jul 2015
Peer-reviewed: Yes

Publication information

Journal: Nanotechnology
Volume: 26
Issue number: 27
Article number: 275301
ISSN (Print): 0957-4484
Ratings: 
  • Scopus rating (2015): CiteScore 6.6 SJR 1.257 SNIP 1.117
Original language: English
ASJC Scopus subject areas: Bioengineering, Chemistry(all), Electrical and Electronic Engineering, Mechanical Engineering, Mechanics of Materials, Materials Science(all)
Keywords: droplet epitaxy, GaAs, nanowires, self-catalyzed

Bibliographical note

EXT="Laukkanen, P."

Source: Scopus
Source ID: 84934916555

Research output: Contribution to journalArticleScientificpeer-review

Electricity production by a microbial fuel cell fueled by brewery wastewater and the factors in its membrane deterioration

Electricity production from brewery wastewater using dual-chamber microbial fuel cells (MFCs) with a tin-coated copper mesh in the anode was investigated by changing the hydraulic retention time (HRT). The MFCs were fed with wastewater samples from the inlet (inflow, MFC-1) and outlet (outflow, MFC-2) of an anaerobic digester of a brewery wastewater treatment plant. Both chemical oxygen demand removal and current density were improved by decreasing HRT. The best MFC performance was with an HRT of 0.5 d. The maximum power densities of 8.001 and 1.843 µW/cm<sup>2</sup> were obtained from reactors MFC-1 and MFC-2, respectively. Microbial diversity at different conditions was studied using PCR-DGGE profiling of 16S rRNA fragments of the microorganisms from the biofilm on the anode electrode. The MFC reactor had mainly Geobacter, Shewanella, and Clostridium species, and some bacteria were easily washed out at lower HRTs. The fouling characteristics of the MFC Nafion membrane and the resulting degradation of MFC performance were examined. The ion exchange capacity, conductivity, and diffusivity of the membrane decreased significantly after fouling. The morphology of the Nafion membrane and MFC degradation were studied using scanning electron microscopy and attenuated total reflection-Fourier transform infrared spectroscopy.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Portland State University, Department of Civil and Environmental Engineering, Yildiz Technical University
Contributors: Çetinkaya, A. Y., Köroğlu, E. O., Demir, N. M., Baysoy, D. Y., Özkaya, B., Çakmakçi, M.
Number of pages: 9
Pages: 1068-1076
Publication date: 20 Jul 2015
Peer-reviewed: Yes

Publication information

Journal: Chinese Journal of Catalysis
Volume: 36
Issue number: 7
ISSN (Print): 0253-9837
Ratings: 
  • Scopus rating (2015): CiteScore 3.4 SJR 0.579 SNIP 0.805
Original language: English
ASJC Scopus subject areas: Catalysis, Chemistry(all)
Keywords: Anaerobic processe, Biofilm, Microbial community, Microbial fuel cell, Wastewater treatment

Bibliographical note

EXT="Çakmakçi, Mehmet"

Source: Scopus
Source ID: 84934932934

Research output: Contribution to journalArticleScientificpeer-review

High quality sub-10 nm graphene nanoribbons by on-chip PS-b-PDMS block copolymer lithography

A block copolymer self-assembly holds great promise as a rapid, cheap and scalable approach to nanolithography. We present a straightforward method for fabrication of sub-10 nm line patterns from a lamellar polystyrene-b-polydimethylsiloxane (SD) block copolymer with a total average molecular weight of 10.5 kg mol-1. Thin SD films directly spin cast onto silicon substrates and on graphene, form regular line patterns of sub-10 nm pitch on the substrates after a few minutes of annealing at 45 °C in the presence of toluene vapour. Perfect pattern alignment was achieved by confining the films inside the trenches of graphoepitaxial substrates. The SD template was furthermore used as a lithographic mask to fabricate high-quality sub-10 nm graphene nanoribbons. This was realized by one step oxygen plasma treatment, which accomplishes three tasks: hardening the PDMS block by oxidation, and etching both the PS block and the graphene under PS. Raman analysis supports the formation of graphene nanoribbons with an average distance between defects corresponding to the oxidized PDMS pitch, with no sign of defects generated in the ribbon channel. This suggests a high degree of protection of the nanoribbons by the hard oxidized PDMS mask formed in situ during oxygen plasma etching.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Frontier Photonics, Department of Micro and Nanotechnology, Danmarks Tekniske Universitet, DTU Informatik, Center for Nanostructured Graphene, Trinity College Dublin
Contributors: Rasappa, S., Caridad, J. M., Schulte, L., Cagliani, A., Borah, D., Morris, M. A., Bøggild, P., Ndoni, S.
Number of pages: 7
Pages: 66711-66717
Publication date: 29 Jul 2015
Peer-reviewed: Yes

Publication information

Journal: RSC Advances
Volume: 5
Issue number: 82
ISSN (Print): 2046-2069
Ratings: 
  • Scopus rating (2015): CiteScore 3.5 SJR 0.947 SNIP 0.838
Original language: English
ASJC Scopus subject areas: Chemistry(all), Chemical Engineering(all)
Source: Scopus
Source ID: 84938940393

Research output: Contribution to journalArticleScientificpeer-review

Evaluation of crushing strength of spray-dried MgAl2O4 granule beds

The crushing strengths of four different experimental magnesium aluminate spinel (MgAl2O4) granule beds were monitored with the axial die pressing test after heat treatments. Precursor, magnesium hydroxide (Mg(OH)2) and magnesium oxide (MgO) as Mg precursor and aluminium oxide hydroxide Al(O)OH and α-Al2O3 as Al precursor, were used for experimental granules, which were manufactured via a dispersion manufacturing and spray-drying process. After spray-drying, granules were heat treated in air at 1000, 1100, 1200, 1300 and 1400 °C. In order to understand the potential effect of precursor, phase structure, morphology, particle size distribution and density of granules on crushing strength behaviour, scanning X-ray diffraction (XRD) was used together with electron microscopy (SEM) and laser diffraction (LDPA) for characterisation. All precursor mixtures formed spherical granules during the spray-drying process and pure spinel phase structure during heat treatment. The crushing strength test results indicated that the Al precursor clearly affected the crushing strength behaviour of experimental granule beds. The highest strength was observed for granule beds with Al(O)OH) as Al and Mg(OH)2 as Mg precursor.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Materials Science, Engineering materials science and solutions (EMASS), VTT Technical Research Centre of Finland
Contributors: Kanerva, U., Suhonen, T., Lagerbom, J., Levänen, E.
Number of pages: 7
Pages: 8494-8500
Publication date: 1 Aug 2015
Peer-reviewed: Yes

Publication information

Journal: Ceramics International
Volume: 41
Issue number: 7
ISSN (Print): 0272-8842
Ratings: 
  • Scopus rating (2015): CiteScore 4 SJR 0.823 SNIP 1.353
Original language: English
ASJC Scopus subject areas: Ceramics and Composites, Process Chemistry and Technology, Electronic, Optical and Magnetic Materials, Surfaces, Coatings and Films, Materials Chemistry
Keywords: Axial pressing, Granule, MgAl<inf>2</inf>O<inf>4</inf> spinel, The crushing strength

Bibliographical note

EXT="Lagerbom, Juha"
EXT="Kanerva, Ulla"

Source: Scopus
Source ID: 84929271760

Research output: Contribution to journalArticleScientificpeer-review

Sol-gel synthesis of quaternary (P2O5)55-(CaO)25-(Na2O)(20-x)-(TiO2) x bioresorbable glasses for bone tissue engineering applications (x = 0, 5, 10, or 15)

In the present study, we report a new and facile sol-gel synthesis of phosphate-based glasses with the general formula of (P2O5)55-(CaO)25-(Na2O)(20-x)-(TiO2) x , where x = 0, 5, 10 or 15, for bone tissue engineering applications. The sol-gel synthesis method allows greater control over glass morphology at relatively low processing temperature (200 °C) in comparison with phosphate-based melt-derived glasses (~1000 °C). The glasses were analyzed using several characterization techniques, including x-ray diffraction (XRD), (31)P magic angle spinning nuclear magnetic resonance ((31)P MAS-NMR), Fourier transform infrared (FTIR) spectroscopy and energy-dispersive x-ray (EDX) spectroscopy, which confirmed the amorphous and glassy nature of the prepared samples. Degradation was assessed by measuring the ion release and pH change of the storage medium. Cytocompatibility was also confirmed by culturing osteoblast-like osteosarcoma cell line MG-63 on the glass microparticles over a seven-day period. Cell attachment to the particles was imaged using scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). The results revealed the potential of phosphate-based sol-gel derived glasses containing 5 or 10 mol% TiO2, with high surface area, ideal dissolution rate for cell attachment and easily metabolized dissolution products, for bone tissue engineering applications.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Integrated Technologies for Tissue Engineering Research (ITTE), UCL Eastman Dental Institute
Contributors: Foroutan, F., Walters, N. J., Owens, G. J., Mordan, N. J., Kim, H. W., de Leeuw, N. H., Knowles, J. C.
Number of pages: 1
Pages: 45025
Publication date: 1 Aug 2015
Peer-reviewed: Yes

Publication information

Journal: Biomedical materials (Bristol, England)
Volume: 10
Issue number: 4
Ratings: 
  • Scopus rating (2015): CiteScore 5.1 SJR 1.118 SNIP 1.118
Original language: English
ASJC Scopus subject areas: Bioengineering, Biomaterials, Biomedical Engineering

Research output: Contribution to journalArticleScientificpeer-review

Influence of relative humidity and physical load during storage on dustiness of inorganic nanomaterials: implications for testing and risk assessment

Dustiness testing using a down-scaled EN15051 rotating drum was used to investigate the effects of storage conditions such as relative humidity and physical loading on the dustiness of five inorganic metal oxide nanostructured powder materials. The tests consisted of measurements of gravimetrical respirable dustiness index and particle size distributions. Water uptake of the powders during 7 days of incubation was investigated as an explanatory factor of the changes. Consequences of these varying storage conditions in exposure modelling were tested using the control banding and risk management tool NanoSafer. Drastic material-specific effects on powder respirable dustiness index were observed with the change in TiO<inf>2</inf> from 30 % RH (639 mg/kg) to 50 % RH (1.5 mg/kg). All five tested materials indicate a decreasing dustiness index with relative humidity increasing from 30 to 70 % RH. Test of powder water uptake showed an apparent link with the decreasing dustiness index. Effects of powder compaction appeared more material specific with both increasing and decreasing dustiness indices observed as an effect of compaction. Tests of control banding exposure models using the measured dustiness indices in three different exposure scenarios showed that in two of the tested materials, one 20 % change in RH changed the exposure banding from the lowest level to the highest. The study shows the importance of powder storage conditions prior to tests for classification of material dustiness indices. It also highlights the importance of correct storage information and relative humidity and expansion of the dustiness test conditions specifically, when using dustiness indices as a primary parameter for source strength in exposure assessment.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Materials Science, Research group: Materials Characterization, Engineering materials science and solutions (EMASS), Department of Micro and Nanotechnology, Denmark Technical University DTU, Finnish Institute of Occupational Health, CIC biomaGUNE, National Research Centre for the Working Environment
Contributors: Levin, M., Rojas, E., Vanhala, E., Vippola, M., Liguori, B., Kling, K. I., Koponen, I. K., Mølhave, K., Tuomi, T., Gregurec, D., Moya, S., Jensen, K. A.
Publication date: 14 Aug 2015
Peer-reviewed: Yes

Publication information

Journal: Journal of Nanoparticle Research
Volume: 17
Issue number: 8
Article number: 337
ISSN (Print): 1388-0764
Ratings: 
  • Scopus rating (2015): CiteScore 3.8 SJR 0.568 SNIP 0.725
Original language: English
ASJC Scopus subject areas: Atomic and Molecular Physics, and Optics, Condensed Matter Physics, Modelling and Simulation, Chemistry(all), Materials Science(all), Bioengineering
Keywords: Dustiness, Exposure assessment, Nanotechnology, Occupational health, Powder storage, Rotating drum
Source: Scopus
Source ID: 84939162642

Research output: Contribution to journalArticleScientificpeer-review

Enhanced photoactive and photoelectrochemical properties of TiO2 sol-gel coated steel by the application of SiO2 intermediate layer

Photocatalysis is a promising solution for purifying air and water from pollutants, yet more efficient photocatalytic materials are needed. A new approach is proposed in this paper for enhancing the photoactive and photoelectrical properties of anatase TiO2 films by applying an intermediate SiO2 film between the TiO2 film and the stainless steel substrate. TiO2 and SiO2 coatings are synthesized by a sol-gel method and the thickness of TiO2 film is varied in order to obtain improved understanding on the role of thickness in photocatalytic and electrochemical performance. The obtained coatings are systematically characterized in terms of microstructure using such techniques as field-emission scanning electron microscopy (FE-SEM), Raman spectroscopy and X-ray diffraction (XRD), that demonstrate, e.g., the anatase phase structure of the TiO2 films. The enhanced photocatalytic properties of SiO2/TiO2 coatings as compared to TiO2 films are verified using methylene blue (MB) discoloration tests, while the improved photoelectrochemical properties are shown by potentiodynamic i-V scans, open circuit potential (OCP) monitoring and electrochemical impedance spectroscopy (EIS). We attribute the beneficial effect of the intermediate SiO2 film on the photocatalytic and photoelectrochemical performance to the high electrical resistance of the SiO2 that imposes a high-energy barrier for electron transfer and, therefore, (partly) insulates the TiO2 film from the substrate and acts as a capacitor for photo-generated electrons under illumination. The presented results show an effective way of enhancing the photocatalytic performance of anatase TiO2 films.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Engineering materials science and solutions (EMASS), Frontier Photonics, Department of Materials Science, Research group: Ceramic materials, Optoelectronics Research Centre, Research group: Nanophotonics, Research group: Surface Engineering, Research group: Materials Characterization
Contributors: Nikkanen, J. P., Huttunen-Saarivirta, E., Salminen, T., Hyvärinen, L., Honkanen, M., Isotahdon, E., Heinonen, S., Levänen, E.
Number of pages: 11
Pages: 533-543
Publication date: 1 Sep 2015
Peer-reviewed: Yes

Publication information

Journal: Applied Catalysis B-Environmental
Volume: 174-175
ISSN (Print): 0926-3373
Ratings: 
  • Scopus rating (2015): CiteScore 12.7 SJR 2.326 SNIP 2.213
Original language: English
ASJC Scopus subject areas: Catalysis, Process Chemistry and Technology, Environmental Science(all)
Keywords: Electrical resistance, Electrochemical impedance spectroscopy, Photocatalysis, Substrate, Titanium dioxide

Bibliographical note

ORG=mol,0.5
ORG=orc,0.5

Source: Scopus
Source ID: 84937762118

Research output: Contribution to journalArticleScientificpeer-review

Searching for a robust strategy for minimizing alkali chlorides in fluidized bed boilers during burning of high SRF-energy-share fuel

To meet the increasing volume of waste to be treated via energy recovery, high SRF-energy-share fuel is being fired in conventional waste-to-energy facilities. In this work, corrosion related risk during firing of 70 e-% share (target fuel) is studied and compared against the base case fuel containing 50 e-% share. Cl and S concentration is highest in the target fuel as a direct result of increasing the proportion of SRF in the fuel mixture. Br, Zn and Pb showed the same trend. Meanwhile, the concentration of Na, K, Al and Si are highly dependent on the type of the SRF fired. The corrosion risk of the base and target fuels are analyzed using the composition of the fine aerosol fraction and deposit samples measured near the vicinity of the superheater. Surprisingly aerosols for the target fuel are less risky - having less Cl and more S, than that of the base fuel. The effects of sulfur based additives - elemental sulfur and sulfate injection, and fuel substitution on the risk of superheater corrosion are likewise analyzed. All these strategies can reduce the concentration of Cl in the aerosols, however it is concluded that sulfate injection is considered as a robust strategy for mitigating alkali chloride formation. Sulfate injection is able to reduce Cl in the aerosols and deposits regardless of the quality of the fuel mixture. Robust strategies are important in ensuring the boiler performance during high SRF-energy share firing. An attempt of linking the quality of the deposits and the properties of the flue gas and aerosols around the superheater using partial least squares regression is also presented.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Urban circular bioeconomy (UrCirBio), University of Jyväskylä, Valmet Technologies Oy, VTT Technical Research Centre of Finland, Department of Chemistry, Renewable Natural Resources and Chemistry of Living Environment, Stora Enso
Contributors: Bajamundi, C. J. E., Vainikka, P., Hedman, M., Silvennoinen, J., Heinanen, T., Taipale, R., Konttinen, J.
Number of pages: 12
Pages: 25-36
Publication date: 1 Sep 2015
Peer-reviewed: Yes

Publication information

Journal: Fuel
Volume: 155
ISSN (Print): 0016-2361
Ratings: 
  • Scopus rating (2015): CiteScore 6.9 SJR 1.781 SNIP 2.111
Original language: English
ASJC Scopus subject areas: Fuel Technology, Energy Engineering and Power Technology, Chemical Engineering(all), Organic Chemistry
Keywords: Alkali chloride mitigation, Corrosion, SRF, Waste-to-energy
Source: Scopus
Source ID: 84928243284

Research output: Contribution to journalArticleScientificpeer-review

Surface Modified Biodegradable Electrospun Membranes as a Carrier for Human Embryonic Stem Cell-Derived Retinal Pigment Epithelial Cells

Human embryonic stem cell-derived retinal pigment epithelial (hESC-RPE) cells are currently undergoing clinical trials to treat retinal degenerative diseases. Transplantation of hESC-RPE cells in conjuction with a supportive biomaterial carrier holds great potential as a future treatment for retinal degeneration. However, there has been no such biodegradable material that could support the growth and maturation of hESC-RPE cells so far. The primary aim of this work was to create a thin porous poly (L-lactide-co-caprolactone) (PLCL) membrane that could promote attachment, proliferation, and maturation of the hESC-RPE cells in serum-free culture conditions. The PLCL membranes were modified by atmospheric pressure plasma processing and coated with collagen IV to enhance cell growth and maturation. Permeability of the membranes was analyzed with an Ussing chamber system. Analysis with scanning electron microscopy, contact angle measurement, atomic force microscopy, and X-ray photoelectron spectroscopy demonstrated that plasma surface treatment augments the surface properties of the membrane, which enhances the binding and conformation of the protein. Cell proliferation assays, reverse transcription-polymerase chain reaction, indirect immunofluoresence staining, trans-epithelial electrical resistance measurements, and in vitro phagocytosis assay clearly demonstrated that the plasma treated PLCL membranes supported the adherence, proliferation, maturation and functionality of hESC-RPE cells in serum-free culture conditions. Here, we report for the first time, how PLCL membranes can be modified with atmospheric pressure plasma processing to enable the formation of a functional hESC-RPE monolayer on a porous biodegradable substrate, which have a potential as a tissue-engineered construct for regenerative retinal repair applications.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Integrated Technologies for Tissue Engineering Research (ITTE), University of Ulster
Contributors: Sorkio, A., Porter, P. J., Juuti-Uusitalo, K., Meenan, B. J., Skottman, H., Burke, G. A.
Number of pages: 14
Pages: 2301-2314
Publication date: 1 Sep 2015
Peer-reviewed: Yes

Publication information

Journal: Tissue Engineering Part A
Volume: 21
Issue number: 17-18
ISSN (Print): 1937-3341
Ratings: 
  • Scopus rating (2015): CiteScore 7.3 SJR 1.536 SNIP 1.099
Original language: English
ASJC Scopus subject areas: Bioengineering, Biochemistry, Biomedical Engineering, Biomaterials, Medicine(all)
Source: Scopus
Source ID: 84940705576

Research output: Contribution to journalArticleScientificpeer-review

Effects of anode potentials on bioelectrogenic conversion of xylose and microbial community compositions

The results on the effects of different anode potentials on current densities, coulombic efficiencies and microbial communities are contradictory and have not been studied with xylose, an important constituent of lignocellulosic materials. In this study, the effects of different anode potentials (+0.2, 0 and -0.2V vs. Ag/AgCl) on current generation, xylose degradation and microbial communities were examined with an exoelectrogenic enrichment culture originating from anaerobic sludge. Anode potential of +0.2V (vs. Ag/AgCl) resulted in the highest current density and coulombic efficiency of 1.5±0.2A/m<sup>2</sup> and 62±11%, respectively, and there was no accumulation of soluble metabolites. With anode potentials of 0 and -0.2V the current densities remained low and acetate, butyrate and propionate were detected in the end of batch runs. Different anode potentials resulted in substantial differences in the anodic bacterial species. At more positive anode potentials, Ochrobactrum intermedium reported to be capable of direct electron transfer dominated. At more negative anode potentials, a known mediator-producer, Alcaligenes faecalis, and Desulfitobacterium hafnience, that has been reported to use mediated electron transfer, were detected. This study shows that the anode potential has a substantial effect on microbial communities and on xylose metabolism.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry, Urban circular bioeconomy (UrCirBio)
Contributors: Kokko, M. E., Mäkinen, A. E., Sulonen, M. L. K., Puhakka, J. A.
Number of pages: 5
Pages: 248-252
Publication date: 5 Sep 2015
Peer-reviewed: Yes
Early online date: 24 Jun 2015

Publication information

Journal: Biochemical Engineering Journal
Volume: 101
ISSN (Print): 1369-703X
Ratings: 
  • Scopus rating (2015): CiteScore 4.6 SJR 0.952 SNIP 1.075
Original language: English
ASJC Scopus subject areas: Biotechnology, Bioengineering, Biomedical Engineering, Environmental Engineering
Keywords: Anaerobic processes, Anode potential, Batch processing, Biocatalysis, Bioconversion, Microbial fuel cell
Source: Scopus
Source ID: 84936752873

Research output: Contribution to journalArticleScientificpeer-review

Molecular Design of Light-Responsive Hydrogels, for in Situ Generation of Fast and Reversible Valves for Microfluidic Applications

Reversible light-responsive hydrogel valves with response characteristics compatible for microfluidics have been obtained by optimization of molecular design of spiropyran photoswitches and gel composition. Self-protonating gel formulations were exploited, wherein acrylic acid was copolymerized in the hydrogel network as an internal proton donor, to achieve a swollen state of the hydrogel in water at neutral pH. Light-responsive properties were endowed upon the hydrogels by copolymerization of spiropyran chromophores, using electron withdrawing and donating groups to tune the gel-swelling and shrinkage behavior. In all cases, the shrinkage was determined by the water diffusion rate, while for the swelling the isomerization kinetics is the rate-determining step. For one hydrogel, reversible and reproducible volume changes were observed. Finally, gel-valves integrated within microfluidic channels were fabricated, allowing reversible and repeatable operation, with opening and closing of the valve in minutes.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Eindhoven University of Technology, Dublin City University
Contributors: Ter Schiphorst, J., Coleman, S., Stumpel, J. E., Ben Azouz, A., Diamond, D., Schenning, A. P. H. J.
Number of pages: 7
Pages: 5925-5931
Publication date: 8 Sep 2015
Peer-reviewed: Yes

Publication information

Journal: Chemistry of Materials
Volume: 27
Issue number: 17
ISSN (Print): 0897-4756
Ratings: 
  • Scopus rating (2015): CiteScore 12.8 SJR 3.958 SNIP 2.038
Original language: English
ASJC Scopus subject areas: Materials Chemistry, Chemical Engineering(all), Chemistry(all)
Source: Scopus
Source ID: 84941088068

Research output: Contribution to journalArticleScientificpeer-review

Cultivation of Nannochloropsis for eicosapentaenoic acid production in wastewaters of pulp and paper industry

The eicosapentaenoic acid (EPA) containing marine microalga Nannochloropsis oculata was grown in an effluent from anaerobic digestion of excess activated sludge from a wastewater treatment plant serving a combination of a pulp and a paper mill and a municipality (digester effluent, DE), mixed with the effluent of the same wastewater treatment plant. The maximum specific growth rate and photosynthesis of N. oculata were similar in the DE medium and in artificial sea water medium (ASW) but after 7. days, algae grown in the DE medium contained seven times more triacylglycerols (TAGs) per cell than cells grown in ASW, indicating mild stress in the DE medium. However, the volumetric rate of EPA production was similar in the ASW and DE media. The results suggest that N. oculata could be used to produce EPA, utilizing the nutrients available after anaerobic digestion of excess activated sludge of a pulp and paper mill.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry, Urban circular bioeconomy (UrCirBio), University of Turku, Department of Biochemistry/Molecular Plant Biology, Department of Biochemistry/Food Chemistry and Food Development
Contributors: Polishchuk, A., Valev, D., Tarvainen, M., Mishra, S., Kinnunen, V., Antal, T., Yang, B., Rintala, J., Tyystjärvi, E.
Number of pages: 8
Pages: 469-476
Publication date: 1 Oct 2015
Peer-reviewed: Yes
Early online date: 2 Jul 2015

Publication information

Journal: Bioresource Technology
Volume: 193
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2015): CiteScore 9.2 SJR 2.243 SNIP 1.899
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Eicosapentaenoic acid, Nannochloropsis, Paper mill, Pulp mill, Wastewater
Source: Scopus
Source ID: 84936059366

Research output: Contribution to journalArticleScientificpeer-review

Submolecular Plasticization Induced by Photons in Azobenzene Materials

We demonstrate experimentally for the first time that the illumination of azobenzene derivatives leads to changes in molecular environment similar to those observed on heating but that are highly heterogeneous at the submolecular scale. This localized photoplasticization, which can be associated with a free volume gradient, helps to understand the puzzling phenomenon of photoinduced macroscopic material flow and photoexpansion upon illumination far below the glass transition temperature (Tg). The findings stem from the correlation of infrared (IR) spectral band shifts measured upon illumination with those measured at controlled temperatures for two amorphous DR1-functionalized azo derivatives, a polymer, pDR1A, and a molecular glass, gDR1. This new approach reveals that IR spectroscopy can be used as an efficient label-free molecular-scale thermometer that allows the assignment of an effective temperature (Teff) to each moiety in these compounds when irradiated. While no band shift is observed upon illumination for the vibrational modes assigned to backbone moieties of pDR1A and gDR1 and a small band shift is found for the spacer moiety, dramatic band shifts are recorded for the azo moiety, corresponding to an increase in Teff of up to nearly 200 °C and a molecular environment that is equivalent to thermal heating well above the bulk Tg of the material. An irradiated azo-containing material thus combines characteristic properties of amorphous materials both below and above its bulk Tg. The direct measurement of Teff is a powerful probe of the local environment at the submolecular scale, paving the way toward better rationalization of photoexpansion and the athermal malleability of azo-containing materials upon illumination below their Tg.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Frontier Photonics, Département de Chimie, Succ. Centre-Ville, Royal Military College of Canada
Contributors: Vapaavuori, J., Laventure, A., Bazuin, C. G., Lebel, O., Pellerin, C.
Number of pages: 8
Pages: 13510-13517
Publication date: 28 Oct 2015
Peer-reviewed: Yes

Publication information

Journal: Journal of the American Chemical Society
Volume: 137
Issue number: 42
ISSN (Print): 0002-7863
Ratings: 
  • Scopus rating (2015): CiteScore 22.4 SJR 6.775 SNIP 2.6
Original language: English
ASJC Scopus subject areas: Catalysis, Chemistry(all), Biochemistry, Colloid and Surface Chemistry
Source: Scopus
Source ID: 84946020103

Research output: Contribution to journalArticleScientificpeer-review

Comparison of different cationized proteins as biomaterials for nanoparticle-based ocular gene delivery

Cationized polymers have been proposed as transfection agents for gene therapy. The present work aims to improve the understanding of the potential use of different cationized proteins (atelocollagen, albumin and gelatin) as nanoparticle components and to investigate the possibility of modulating the physicochemical properties of the resulting nanoparticle carriers by selecting specific protein characteristics in an attempt to improve current ocular gene-delivery approaches. The toxicity profiles, as well as internalization and transfection efficiency, of the developed nanoparticles can be modulated by modifying the molecular weight of the selected protein and the amine used for cationization. The most promising systems are nanoparticles based on intermediate molecular weight gelatin cationized with the endogenous amine spermine, which exhibit an adequate toxicological profile, as well as effective association and protection of pDNA or siRNA molecules, thereby resulting in higher transfection efficiency and gene silencing than the other studied formulations.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Integrated Technologies for Tissue Engineering Research (ITTE), Federal University of Rio Grande do Sul, University of Santiago de Compostela (USC), University Clinical Hospital of Santiago de Compostela (IDIS)
Contributors: Zorzi, G. K., Párraga, J. E., Seijo, B., Sanchez, A.
Number of pages: 9
Pages: 533-541
Publication date: 1 Nov 2015
Peer-reviewed: Yes

Publication information

Journal: Colloids and Surfaces B: Biointerfaces
Volume: 135
ISSN (Print): 0927-7765
Ratings: 
  • Scopus rating (2015): CiteScore 6.9 SJR 1.085 SNIP 1.244
Original language: English
ASJC Scopus subject areas: Biotechnology, Surfaces and Interfaces, Physical and Theoretical Chemistry, Colloid and Surface Chemistry
Keywords: Cationized proteins, Gene therapy, Nanoparticles, pDNA, siRNA
Source: Scopus
Source ID: 84939622417

Research output: Contribution to journalArticleScientificpeer-review

Effect of rubber polarity on selective wetting of carbon nanotubes in ternary blends

Based on atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR) analysis of the rubber-filler gel (wetting concept) the kinetics of selective wetting of carbon nanotubes (CNTs) in ternary styrene butadiene rubber (SBR)/butadiene rubber (BR)/natural rubber (NR) blends was qualitatively and quantitatively characterized. Almost all CNTs are found to be wetted by the non-polar NR but not by the other non-polar rubber like BR or weakly polar SBR. It was proposed that phospholipids, which are linked to the α-terminal of NR can interact with the CNT surface through cation-π interactions forming strong bonding between NR and CNTs. Using the corrected surface tension value of NR, which involves the effect of phospholipids found in our previous work the selective wetting of CNTs in ternary rubber blends can be well predicted using the Z-model for a thermodynamic equilibrium state. By replacing the non-polar BR by a polar rubber like nitrile butadiene rubber (NBR) as a blend component CNTs are wetted by NBR slightly more than by NR thanks to the strong interaction between CNTs and nitrile groups of NBR. SBR remains unbound to CNTs in both blends.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Engineering materials science and solutions (EMASS), Institut für Polymerwerkstoffe E.V., Martin-Luther-University Halle-Wittenberg, Fraunhofer IWM, Vodafone Department of Mobile Communications Systems, Leibniz-Institut für Polymerforschung Dresden E.V., Vietnamese Academy of Science and Technology Institute of Chemistry, Polymer Service GmbH Merseburg
Contributors: Le, H. H., Parsaker, M., Sriharish, M. N., Henning, S., Menzel, M., Wießner, S., Das, A., Do, Q. K., Heinrich, G., Radusch, H. J.
Number of pages: 12
Pages: 960-971
Publication date: 1 Nov 2015
Peer-reviewed: Yes

Publication information

Journal: Express Polymer Letters
Volume: 9
Issue number: 11
ISSN (Print): 1788-618X
Ratings: 
  • Scopus rating (2015): CiteScore 5.4 SJR 0.929 SNIP 1.583
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all), Physical and Theoretical Chemistry, Polymers and Plastics, Organic Chemistry, Materials Chemistry
Keywords: Carbon nanotubes, Manocomposites, Rubber blends, Selective filler wetting
Source: Scopus
Source ID: 84940868023

Research output: Contribution to journalArticleScientificpeer-review

Simultaneous nutrient removal and lipid production with Chlorella vulgaris on sterilized and non-sterilized anaerobically pretreated piggery wastewater

Piggery wastewater is a potent nutrient source for microalgal lipid production. Wastewater has been usually sterilized when used for microalgal cultivation. This is uneconomical in large-scale applications. Therefore, lipid productivity of Chlorella vulgaris CY5 using sterilized and non-sterilized diluted anaerobically pretreated piggery wastewater was studied in batch reactors. The maximum average lipid productivity was obtained after 12 days of incubation and it was higher with the sterilized wastewater than with the non-sterilized one (117g/L/d vs. 91.3g/L/d), due to the higher biomass concentration. Because of the unexpected increase of dissolved organic carbon (DOC) in the cultures, second experiment was conducted to characterize the composition of produced DOC in non-sterilized wastewater. Carbohydrate content increased in the liquid phase but decreased in the biomass after nitrogen had been exhausted. After 12 days of incubation, soluble chemical oxygen demand (COD<inf>s</inf>) was 414±56mg/L, biomass production was 2.8±0.15g/L, and lipid content was 30.3±1.2wt%. Average lipid productivity from day zero to day 12 was 70.5±1.1g/L/d. C. vulgaris removed nutrients from the non-sterilized wastewater and produced oleaginous biomass, although the lipid productivity was higher with sterilized wastewater.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry, Urban circular bioeconomy (UrCirBio), Center of Bioscience and Biotechnology, Research Center for Energy Technology and Strategy, National Cheng Kung University, Department of Environmental Engineering, Department of Chemical Engineering
Contributors: Marjakangas, J. M., Chen, C. Y., Lakaniemi, A. M., Puhakka, J. A., Whang, L. M., Chang, J. S.
Number of pages: 8
Pages: 177-184
Publication date: 5 Nov 2015
Peer-reviewed: Yes
Early online date: 23 Jul 2015

Publication information

Journal: Biochemical Engineering Journal
Volume: 103
ISSN (Print): 1369-703X
Ratings: 
  • Scopus rating (2015): CiteScore 4.6 SJR 0.952 SNIP 1.075
Original language: English
ASJC Scopus subject areas: Biotechnology, Bioengineering, Biomedical Engineering, Environmental Engineering
Keywords: Aerobic process, Lipid production, Microalgae, Piggery wastewater, Sterilization, Wastewater treatment
Source: Scopus
Source ID: 84939202209

Research output: Contribution to journalArticleScientificpeer-review

Tri-functionality of Fe3O4-embedded carbon microparticles in microalgae harvesting

Microalgae have received significant attention as promising resources for biodiesel. However, the downstream processes for the production of biodiesel, which range from cultivation, harvesting, dewatering, and lipid extraction to oil upgrading, are economically impracticable and can be improved. Therefore, efficient microalgal harvesting and integrated technologies are required to realize microalgae-based biodiesel. Herein, tri-functional (cationic, magnetic, and lipophilic) carbon microparticles filled with magnetite (Fe<inf>3</inf>O<inf>4</inf>) are synthesized through one-step aerosol spray pyrolysis and applied in microalgal harvesting and serial microalgal lipid entrapment. Carbon microparticles are tri-functional in the following respects: (i) the cationic carbon microparticles facilitate flocculation with anionic microalgae due to electrostatic attractions; (ii) the magnetic properties of the carbon microparticles, owing to embedded magnetites, enable the separation of microalgal flocs from low concentration cultures (~2gL<sup>-1</sup>) with a separation efficiency of 99%; and (iii) the lipophilicity enables the recovery of lipid droplets extracted from oleaginous microalgae. Microalgal lipids are directly separated through adsorption onto magnetic carbon microparticles from concentrated microalgal slurries after harvesting. The tri-functionality may facilitate the integrated use of magnetic carbon microparticles in microalgal biorefineries and the tri-functional microparticles could potentially be applied in various areas such as biomedicine, catalysis, magnetism, energy materials, and environmental remediation.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Urban circular bioeconomy (UrCirBio), KAIST, Korea Institute of Energy Research
Contributors: Seo, J. Y., Lee, K., Ramasamy, P., Kim, B., Lee, S. Y., Oh, Y. K., Park, S. B.
Number of pages: 9
Pages: 206-214
Publication date: 5 Nov 2015
Peer-reviewed: Yes

Publication information

Journal: Chemical Engineering Journal
Volume: 280
ISSN (Print): 1385-8947
Ratings: 
  • Scopus rating (2015): CiteScore 8.6 SJR 1.676 SNIP 1.912
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all), Chemistry(all), Industrial and Manufacturing Engineering, Environmental Chemistry
Keywords: Aerosol spray pyrolysis, Cationic functionality, Lipophilicity, Magnetic materials, Microalgae harvesting
Source: Scopus
Source ID: 84933567826

Research output: Contribution to journalArticleScientificpeer-review

Graphene-intercalated Fe2O3/TiO2 heterojunctions for efficient photoelectrolysis of water

Interfacial modification of α-Fe2O3/TiO2 multilayer photoanodes by intercalating few-layer graphene (FLG) was found to improve water splitting efficiency due to superior transport properties, when compared to individual iron and titanium oxides and heterojunctions thereof. Both metal oxides and graphene sheets were grown by plasma-enhanced chemical vapor deposition. Compared to the onset potential achieved for α-Fe2O3 films (1 V vs. RHE), the α-Fe2O3/TiO2 bilayer structure yielded a better onset potential (0.3 V vs. RHE). Heterojunctioned bilayers exhibited a higher photocurrent density (0.32 mA cm-2 at 1.23 V vs. RHE) than the single α-Fe2O3 layer (0.22 mA cm-2 at 1.23 V vs. RHE), indicating more efficient light harvesting and higher concentration of photogenerated charge carriers. For more efficient charge transport at the interface, a few layer graphene sheet was intercalated into the α-Fe2O3/TiO2 interface, which substantially increased the photocurrent density to 0.85 mA cm-2 (1.23 V vs. RHE) and shifted the onset potential (0.25 V vs. RHE). Ultrafast transient absorption spectroscopy studies indicated that the incorporation of FLG between the α-Fe2O3 and TiO2 layers resulted in reduced recombination in the α-Fe2O3 layer. The results showed that graphene intercalation improved the charge separation and the photocurrent density of the FTO/α-Fe2O3/FLG/TiO2 system.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Supramolecular photochemistry, Universitat zu Koln, Institute of Inorganic Chemistry, Ruhr-Universität Bochum
Contributors: Kaouk, A., Ruoko, T. P., Gönüllü, Y., Kaunisto, K., Mettenbörger, A., Gurevich, E., Lemmetyinen, H., Ostendorf, A., Mathur, S.
Number of pages: 7
Pages: 101401-101407
Publication date: 13 Nov 2015
Peer-reviewed: Yes

Publication information

Journal: RSC Advances
Volume: 5
Issue number: 123
ISSN (Print): 2046-2069
Ratings: 
  • Scopus rating (2015): CiteScore 3.5 SJR 0.947 SNIP 0.838
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all), Chemistry(all)
Electronic versions: 
Source: Scopus
Source ID: 84948652698

Research output: Contribution to journalArticleScientificpeer-review

Polypyrrole coating on poly-(lactide/glycolide)-β-tricalcium phosphate screws enhances new bone formation in rabbits

Polypyrrole (PPy) has gained interest as an implant material due to its multifunctional properties and its high compatibility with several cell and tissue types. For the first time, the biocompatibility and osteointegration of PPy coating, incorporated with chondroitin sulfate (CS), were studied in vivo by implanting PPy-coated bioabsorbable bone fixation composite screws of poly-(lactide/glycolide) copolymer (PLGA) and β-tricalcium phosphate (TCP) into New Zealand white rabbits. Uncoated bioabsorbable polymer composite screws and commercially available stainless steel cortical screws were used as reference implants. The rabbits were euthanized 12 and 26 weeks after the implantation. The systemic effects were evaluated from food and water consumption, body weight, body temperature, clinical signs, blood samples, internal organ weights, and histological examination. Local effects were studied from bone tissue and surrounding soft tissue histology. New bone formation was evaluated by micro-computed tomography, tetracycline labeling and torsion tests. Torsion tests were performed in order to capture the peak value of the torsion force during the course of the screw's loosening. The coated screws induced significantly more bone formation than the uncoated screws. In addition, none of the implants induced any systemic or local toxicity. The results suggest that PPy is biocompatible with bone tissue and is a potential coating for enhancing osteointegration in orthopedic implants.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Electronics and Communications Engineering, Research group: Computational Biophysics and Imaging Group, Research group: Biomaterials and Tissue Engineering Group, BioMediTech, Integrated Technologies for Tissue Engineering Research (ITTE), Fudan University, University of Wollongong, VTT Technical Research Centre of Finland, Tampere University Hospital, University of Oulu, Univ Helsinki, Helsinki University Central Hospital, University of Helsinki, Cent Hosp, Dept Med, Div Nephrol, University of Twente
Contributors: Zhao, M. D., Björninen, M., Cao, L., Wang, H. R., Pelto, J., Li, X. Q., Hyttinen, J., Jiang, Y. Q., Kellomäki, M., Miettinen, S., Sándor, G. K., Seppänen, R., Haimi, S., Dong, J.
Publication date: 27 Nov 2015
Peer-reviewed: Yes

Publication information

Journal: Biomedical Materials
Volume: 10
Issue number: 6
Article number: 065016
ISSN (Print): 1748-6041
Ratings: 
  • Scopus rating (2015): CiteScore 5.1 SJR 1.118 SNIP 1.118
Original language: English
ASJC Scopus subject areas: Bioengineering, Biomaterials, Biomedical Engineering
Keywords: absorbable screw, biocompatibility, in vivo, osteointegration, polypyrrole (PPy)

Bibliographical note

EXT="Pelto, Jani"

Source: Scopus
Source ID: 84950121168

Research output: Contribution to journalArticleScientificpeer-review

Modeling carbon dioxide transport in PDMS-based microfluidic cell culture devices

Maintaining a proper pH level is crucial for successful cell culturing. Mammalian cells are commonly cultured in incubators, where the cell culture medium is saturated with a mixture of air and 5% carbon dioxide (CO<inf>2</inf>). Therefore, to keep cell culture medium pH in an acceptable level outside these incubators, a suitable CO<inf>2</inf> concentration must be dissolved in the medium. However, it can be very difficult to control and measure precisely local concentration levels. Furthermore, possible undesired concentration gradients generated during long-term cell culturing are almost impossible to detect. Therefore, we have developed a computational model to estimate CO<inf>2</inf> transport in silicone-based microfluidic devices. An extensive set of experiments was used to validate the finite element model. The model parameters were obtained using suitable measurement set-ups and the model was validated using a fully functional cell cultivation device. The predictions obtained by the simulations show very good responses to experiments. It is shown in this paper how the model helps to understand the dynamics of CO<inf>2</inf> transport in silicone-based cell culturing devices possessing different geometries, thus providing cost-effective means for studying different device designs under a variety of experimental conditions without the need of actual testing. Finally, based on the results from the computational model, an alternative strategy for feeding CO<inf>2</inf> is proposed to accelerate the system performance such that a faster and more uniform CO<inf>2</inf> concentration response is achieved in the area of interest.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Automation Science and Engineering, Department of Materials Science, Research group: Paper Converting and Packaging, BioMediTech, Integrated Technologies for Tissue Engineering Research (ITTE), BioMediTech
Contributors: Mäki, A. J., Peltokangas, M., Kreutzer, J., Auvinen, S., Kallio, P.
Number of pages: 10
Pages: 515-524
Publication date: 1 Dec 2015
Peer-reviewed: Yes

Publication information

Journal: Chemical Engineering Science
Volume: 137
ISSN (Print): 0009-2509
Ratings: 
  • Scopus rating (2015): CiteScore 5 SJR 1.022 SNIP 1.563
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all), Chemistry(all), Applied Mathematics, Industrial and Manufacturing Engineering
Keywords: Carbon dioxide, Finite element method, Mass transport, Microfluidics cell culturing, Numerical simulation, pH
Electronic versions: 
URLs: 

Bibliographical note

ORG=ase,0.9
ORG=mol,0.1

Source: Scopus
Source ID: 84938149959

Research output: Contribution to journalArticleScientificpeer-review

The formation and physical properties of the particle emissions from a natural gas engine

Natural gas engine particle emissions were studied using an old gasoline engine modified to run with natural gas. The tests were steady-state tests performed on two different low loads in an engine dynamometer. Exhaust particle number concentration, size distribution, volatility and electric charge were measured. Exhaust particles were observed to have peak diameters below 10 nm. To get the full picture of particle emissions from natural gas engines, size range 1-5 nm is relevant and important to take into consideration. A particle size magnifier (PSM) was used in this engine application for measuring particles smaller than 3 nm and it proved to be a useful instrument when measuring natural gas engine exhaust particles. It is concluded that the detected particles probably originated from the engine cylinders or their vicinity and grew to detectable sizes in the sampling process because a small fraction of the particles were observed to carry electric charge and the particles did not evaporate totally at 265°C.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Physics, Research area: Aerosol Physics, Research group: The Instrumentation, Emissions, and Atmospheric Aerosols Group, Engineering materials science and solutions (EMASS), Urban circular bioeconomy (UrCirBio), Atmospheric Composition Research, VTT Technical Research Centre of Finland, Finnish Meteorological Institute
Contributors: Alanen, J., Saukko, E., Lehtoranta, K., Murtonen, T., Timonen, H., Hillamo, R., Karjalainen, P., Kuuluvainen, H., Harra, J., Keskinen, J., Rönkkö, T.
Number of pages: 7
Pages: 155-161
Publication date: 15 Dec 2015
Peer-reviewed: Yes

Publication information

Journal: Fuel
Volume: 162
ISSN (Print): 0016-2361
Ratings: 
  • Scopus rating (2015): CiteScore 6.9 SJR 1.781 SNIP 2.111
Original language: English
ASJC Scopus subject areas: Fuel Technology, Energy Engineering and Power Technology, Chemical Engineering(all), Organic Chemistry
Keywords: Fine particle emission, Internal combustion engine, Natural gas, Particle formation
Source: Scopus
Source ID: 84941782885

Research output: Contribution to journalArticleScientificpeer-review

Accelerated deactivation studies of the natural-gas oxidation catalyst-Verifying the role of sulfur and elevated temperature in catalyst aging

Accelerated deactivation, caused by thermal aging (TA) and/or sulfur+water poisoning (SW), of the PtPd/γ-Al2O3 natural-gas oxidation catalyst was studied. Thermal aging and poisoning treatments were performed separately and with varied combinations and comprehensive characterization of the catalyst was carried out after each step. The fresh catalyst has small, oxidized PtPd particles (<5nm) uniformly distributed in the γ-alumina washcoat. After the SW-treatment, a small amount of bulk aluminum sulfate was observed near the slightly grown noble metal particles. During the thermal aging, γ-alumina changed to δ-/θ- and α-alumina. In addition, total decomposition of oxidized Pt and partly decomposition of oxidized Pd occurred resulting in the formation of the grown noble metal particles with a bimetallic PtPd core and a polycrystalline PdO shell. Also few, small (~5nm) bimetallic PtPd particles were still detected. In the TA+SW-treated catalyst with grown noble metal particles, a small amount of bulk aluminum sulfate was detected and it was randomly distributed over the noble metal particles and washcoat. The activity in the terms of methane conversion over the TA-, SW-, and SW+TA-treated catalysts was similar but it was decreased compared to the fresh catalyst. The activity of the TA+SW-treated catalyst was drastically decreased compared to the fresh catalyst due to significant morphological changes and aluminum sulfate formation.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Materials Science, Research group: Materials Characterization, University of Oulu, Aalto University, Chalmers University of Technology, Dinex Ecocat Oy
Contributors: Honkanen, M., Kärkkäinen, M., Kolli, T., Heikkinen, O., Viitanen, V., Zeng, L., Jiang, H., Kallinen, K., Huuhtanen, M., Keiski, R. L., Lahtinen, J., Olsson, E., Vippola, M.
Number of pages: 10
Pages: 439-448
Publication date: 2016
Peer-reviewed: Yes
Early online date: 1 Oct 2015

Publication information

Journal: Applied Catalysis B-Environmental
ISSN (Print): 0926-3373
Ratings: 
  • Scopus rating (2016): CiteScore 14.9 SJR 2.693 SNIP 2.208
Original language: English
ASJC Scopus subject areas: Catalysis, Process Chemistry and Technology, Environmental Science(all)
Keywords: Deactivation, Palladium, Platinum, Sulfur poisoning, Thermal aging
Electronic versions: 
URLs: 
Source: Scopus
Source ID: 84943638016

Research output: Contribution to journalArticleScientificpeer-review

A novel generic algorithm for robust physiological signal classification

The last decade has witnessed a significant interest in widespread usage of wearable monitoring devices that could provide continuous measurements of physiological parameters. The design and development of these devices has attracted lots of attention in industry and scientific associations. Advanced and miniaturized electronics with signal acquisition technologies provide a possibility for designing only one device for several physiological measurement purposes. Therefore for designing such an automatic system, a simple generic algorithm for physiological signal classification is required. In this paper, a novel generic algorithm for robust physiological signal classification is presented. The architecture of the proposed system includes preprocessing, feature extraction and a neural network method. Our generic algorithm was able to distinguish different physiological signals such as electrocardiogram (ECG), respiratory signal, seismocardiogram (SCG), electromyogram (EMG) and photoplethysmogram with 100% accuracy. The algorithm was also evaluated by noisy signals with 10 and 20 dB levels of added noise and the same results were achieved. The algorithm could be implemented in healthcare monitoring systems and it can provide the possibility of monitoring various physiological signals with only one device.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Electronics and Communications Engineering, Research group: Physiological Measurement Systems and Methods Group
Contributors: Mahdiani, S., Vanhala, J., Viik, J.
Number of pages: 6
Pages: 1038-1043
Publication date: 2016

Host publication information

Title of host publication: XIV Mediterranean Conference on Medical and Biological Engineering and Computing 2016 : MEDICON 2016, March 31st–April 2nd 2016, Paphos, Cyprus
Publisher: Springer Verlag
ISBN (Print): 978-3-319-32701-3
ISBN (Electronic): 978-3-319-32703-7

Publication series

Name: IFMBE Proceedings
Volume: 57
ISSN (Print): 1680-0737
ASJC Scopus subject areas: Biomedical Engineering, Bioengineering
Keywords: Classifier, Generic algorithm, Neural network, Physiological signals, Wearable devices

Bibliographical note

INT=elt,"Mahdiani, Shadi"
JUFOID=58152

Source: Scopus
Source ID: 84968662326

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

A review of transient suppression methods of IIR notch filters used for power-line interference rejection in ECG measurement

Bioelectric signals are often corrupted by noise. The most common form of noise is power-line interference and its harmonics. A convenient way for eliminating these unwanted components is to use a single or multiple notch filters. One of the problems about this approach is the effect of transient response of the filter at the beginning of its output in short time measurements. In this work, three initialization methods, which can be used to reduce/overcome this problem are reviewed and their performance and computational complexity are evaluated using ECG as an example signal. These methods are projection initialization, pole radius-varying filtering and vector projection. Additionally, some implementation variations and memory usage considerations are discussed. Our study shows that, pole radius-varying method is computationally cheap but introduces longer transient than the others. On the other hand, vector projection provides a more accurate reconstruction of the signal in the transient part of the output but with a more expensive computation. There are also two drawbacks about vector projection. One is its computational complexity dependency to the sampling frequency of the signal and the other is the fact that it cannot provide the results in real-time.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Automation Science and Engineering, Research area: Microsystems, Research area: Measurement Technology and Process Control
Contributors: Mahdiani, S., Jeyhani, V., Vehkaoja, A.
Number of pages: 6
Pages: 151-156
Publication date: 2016

Host publication information

Title of host publication: IFMBE Proceedings
Volume: 57
Publisher: Springer Verlag
ISBN (Print): 9783319327013

Publication series

Name: IFMBE Proceedings
ISSN (Print): 1680-0737
ASJC Scopus subject areas: Biomedical Engineering, Bioengineering
Keywords: ECG, Filter, IIR, Initialization, Transient

Bibliographical note

INT=ase,"Jeyhani, Vala"
INT=elt,"Mahdiani, Shadi"

Source: Scopus
Source ID: 84968571748

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

A tool for geometrical measurements of orthognathic surgery changes using cone beam computed tomography

Cone Beam Computed Tomography has become quite popular in craniofacial imaging. Tools for analyzing the volumetric data however have not caught up with the recent industry demands. Most of the analysis in 3D is primarily based on techniques used in 2D format, thus adding some limitations to the post diagnostic capabilities of the imaging modality. We have developed a technique to measure the geometry of the CBCT volumes and find the changes in the facial structures after the surgery, all in a technically non-intensive and reproducible way.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Electronics and Communications Engineering, Research group: Quantative medical imaging, Medical Imaging Center, Tampere University Hospital
Contributors: Prakash, M., Peltomäki, T., Eskola, H.
Number of pages: 4
Pages: 430-433
Publication date: 2016

Host publication information

Title of host publication: XIV Mediterranean Conference on Medical and Biological Engineering and Computing 2016 : MEDICON 2016, March 31st–April 2nd 2016, Paphos, Cyprus
Publisher: Springer Verlag
ISBN (Print): 978-3-319-32701-3
ISBN (Electronic): 978-3-319-32703-7

Publication series

Name: IFMBE Proceedings
Volume: 57
ISSN (Print): 1680-0737
ASJC Scopus subject areas: Biomedical Engineering, Bioengineering
Keywords: CBCT, Image registration, Landmark setting, Orthognathic surgery

Bibliographical note

JUFOID=58152

Source: Scopus
Source ID: 84968616757

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Biological and Bioelectrochemical Recovery of Critical and Scarce Metals

Metal-bearing solid and liquid wastes are increasingly considered as secondary sources of critical and scarce metals. Undoubtedly, microorganisms are a cost-effective resource for extracting and concentrating diffuse elements from secondary sources. Microbial biotechnology for extracting base metals from ores and treatment of metal-laden wastewaters has already been applied at full scale. By contrast, microbe-metal interactions in the recovery of scarce metals and a few critical metals have received attention, whereas the recovery of many others has been barely explored. Therefore, this article explores and details the potential application of microbial biotechnologies in the recovery of critical and scarce metals. In the past decade bioelectrochemical systems have emerged as a new technology platform for metal recovery coupled to the removal of organic matter. Overview of potential applications of microorganisms in critical metal recovery.Engineering of microbe-metal interactions for recovering rare earth elements and platinum group metals.Reductive mineral dissolution is a new dimension to biomining.Bioelectrochemical systems offer a new technology platform in metal recovery.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry, Biofouling and Biofilm Processes Section, Bhabha Atomic Research Centre, Council of Scientific and Industrial Research India, Hydraulic and Environmental Engineering (IHE) Inst. for Water Education
Contributors: Nancharaiah, Y. V., Mohan, S. V., Lens, P. N. L.
Number of pages: 19
Pages: 137-155
Publication date: 2016
Peer-reviewed: Yes

Publication information

Journal: Trends in Biotechnology
Volume: 34
Issue number: 2
ISSN (Print): 0167-7799
Ratings: 
  • Scopus rating (2016): CiteScore 22 SJR 4.203 SNIP 3.169
Original language: English
ASJC Scopus subject areas: Biotechnology, Bioengineering
Keywords: Bioelectrochemical systems, Biomining, Bioprecipitation, Biorecovery, Critical metals, Microbial fuel cells, Platinum group metals, Rare earth elements
Source: Scopus
Source ID: 84961085643

Research output: Contribution to journalArticleScientificpeer-review

Cell-wall disruption and lipid/astaxanthin extraction from microalgae: Chlorella and Haematococcus

Recently, biofuels and nutraceuticals produced from microalgae have emerged as major interests, resulting in intensive research of the microalgal biorefinery process. In this paper, recent developments in cell-wall disruption and extraction methods are reviewed, focusing on lipid and astaxanthin production from the biotechnologically important microalgae Chlorella and Haematococcus, respectively. As a common, critical bottleneck for recovery of intracellular components such as lipid and astaxanthin from these microalgae, the composition and structure of rigid, thick cell-walls were analyzed. Various chemical, physical, physico-chemical, and biological methods applied for cell-wall breakage and lipid/astaxanthin extraction from Chlorella and Haematococcus are discussed in detail and compared based on efficiency, energy consumption, type and dosage of solvent, biomass concentration and status (wet/dried), toxicity, scalability, and synergistic combinations. This report could serve as a useful guide to the implementation of practical downstream processes for recovery of valuable products from microalgae including Chlorella and Haematococcus.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Korea Institute of Energy Research, KAIST
Contributors: Kim, D. Y., Vijayan, D., Praveenkumar, R., Han, J. I., Lee, K., Park, J. Y., Chang, W. S., Lee, J. S., Oh, Y. K.
Pages: 300-310
Publication date: 2016
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 199
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2016): CiteScore 9.9 SJR 2.215 SNIP 1.945
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Astaxanthin, Chlorella, Extraction, Haematococcus, Lipid

Research output: Contribution to journalArticleScientificpeer-review

Composites of high-temperature thermomechanical pulps and polylactic acid

High-temperature thermomechanical pulps (HT-TMP, defibrated at 150 to 170 °C) were compared to a reference TMP (defibrated at 130 °C) as a reinforcement for polylactic acid (PLA). Composites were prepared by melt compounding, followed by injection molding, gradually increasing the used fiber content from 0 to 20 wt.%. The injection-molded specimens were characterized by tensile and impact strength tests, scanning electron microscopy, water absorption tests, and differential scanning calorimetry. The TMP fiber damage was also characterized before and after melt compounding by optical analysis. At 20% fiber content, the Young's modulus increased significantly, while the tensile strength remained unchanged and the impact strength decreased slightly. All fibers suffered damage during melt compounding, but the tensile strength remained about the same as in pure PLA. All types of TMP were able to increase the PLA rate of crystallization. The HT-TMP fibers were dispersed more evenly in PLA than the 130 °C TMP. The 170 °C TMP produced composites of lower water absorption than the other two TMP types, probably because of its lower hemicellulose content and its higher surface coverage by lignin.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Materials Science, Research group: Plastics and Elastomer Technology, Aalto University
Contributors: Solala, I., Koistinen, A., Siljander, S., Vuorinen, J., Vuorinen, T.
Number of pages: 16
Pages: 1125-1140
Publication date: 2016
Peer-reviewed: Yes

Publication information

Journal: BioResources
Volume: 11
Issue number: 1
ISSN (Print): 1930-2126
Ratings: 
  • Scopus rating (2016): CiteScore 2.5 SJR 0.493 SNIP 0.877
Original language: English
ASJC Scopus subject areas: Waste Management and Disposal, Environmental Engineering, Bioengineering
Keywords: High-temperature thermomechanical pulp, Hydrophobic fibers, Mechanical properties, Polylactic acid, Thermal properties, Wood fiber composites
Source: Scopus
Source ID: 84949921508

Research output: Contribution to journalArticleScientificpeer-review

Decoding the Morphological Diversity in Two Dimensional Crystalline Porous Polymers by Core Planarity Modulation

Two new chemically stable triazine- and phenyl-core-based crystalline porous polymers (CPPs) have been synthesized using a single-step template-free solvothermal route. Unique morphological diversities were observed for these CPPs [2,3-DhaTta (ribbon) and 2,3-DhaTab (hollow sphere)] by simply altering the linker planarity. A detailed time-dependent study established a significant correlation between the molecular level structures of building blocks with the morphology of CPPs. Moreover, a DFT study was done for calculating the interlayer stacking energy, which revealed that the extent of stacking efficiency is responsible for governing the morphological diversity in these CPPs.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: CSIR-National Chemical Laboratory, Indian Institute of Technology Kanpur, Indian Institute of Technology Bombay, Jacobs University Bremen, Polymer Science and Engineering Division
Contributors: Halder, A., Kandambeth, S., Biswal, B. P., Kaur, G., Roy, N. C., Addicoat, M., Salunke, J. K., Banerjee, S., Vanka, K., Heine, T., Verma, S., Banerjee, R.
Number of pages: 5
Pages: 7806-7810
Publication date: 2016
Peer-reviewed: Yes

Publication information

Journal: Angewandte Chemie (International Edition)
Volume: 55
Issue number: 27
ISSN (Print): 1433-7851
Ratings: 
  • Scopus rating (2016): CiteScore 18.7 SJR 5.954 SNIP 2.185
Original language: English
ASJC Scopus subject areas: Catalysis, Chemistry(all)
Keywords: covalent organic frameworks, density functional calculations, dihedral angles, morphology, stacking interactions
Source: Scopus
Source ID: 84960155135

Research output: Contribution to journalArticleScientificpeer-review

Enhanced adsorption of orthophosphate and copper onto hydrochar derived from sewage sludge by KOH activation

Hydrothermal carbonization producing hydrochar from organic waste is increasingly gaining attention to deal with the challenge of excess waste activated sludge produced during centralized aerobic wastewater treatment. Hydrochar is used as an adsorbent for the removal of organics, metals and biotic contaminants. This study demonstrated the application of KOH activated hydrochar, called enhanced hydrochar (EHC) derived from sewage sludge, for the removal of orthophosphate from wastewater by means of batch adsorption, zetametry and infrared spectroscopy. The maximum Qe-PO4 3− of EHC was 14.3 mg orthophosphate adsorbed per g of EHC when the initial orthophosphate concentration was increased to 150 mg L−1. The application of orthophosphate removal by EHC from the effluent of a constructed wetland was demonstrated by achieving more than 97% orthophosphate removal at an EHC dosage of 6.0 g L−1 and an initial orthophosphate concentration of 13.1 mg L−1. pH dependent adsorption experiments and infrared spectroscopy showed the orthophosphate removal by EHC was due to the replacement of hydroxyl groups by orthophosphate in the EHC. Acid-base titration showed the KOH washing of the raw hydrochar (RHC) led to a 1.7 times increase in the hydroxyl groups in EHC compared to RHC. This study further confirmed the higher uptake capacity of EHC compared to RHC towards copper as a model divalent cation. EHC can thus be applied for the removal of both anions (orthophosphate) and cations (copper) from wastewater.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry, Hydraulic and Environmental Engineering (IHE) Inst. for Water Education, Zurich University of Applied Sciences
Contributors: Spataru, A., Jain, R., Chung, J. W., Gerner, G., Krebs, R., Lens, P. N. L.
Number of pages: 8
Pages: 101827-101834
Publication date: 2016
Peer-reviewed: Yes

Publication information

Journal: RSC Advances
Volume: 6
Issue number: 104
ISSN (Print): 2046-2069
Ratings: 
  • Scopus rating (2016): CiteScore 4.1 SJR 0.889 SNIP 0.757
Original language: English
ASJC Scopus subject areas: Chemistry(all), Chemical Engineering(all)
Source: Scopus
Source ID: 84994048409

Research output: Contribution to journalArticleScientificpeer-review

Fire-safe and environmentally friendly nanocomposites based on layered double hydroxides and ethylene propylene diene elastomer

In this work we describe layered double hydroxide (LDH), known as naturally occurring hydrotalcite, based rubber composites that can serve as outstanding fire retardant elastomeric materials. The preparation and detailed characterization of these composites are presented in this study. The inherent slow sulfur cure nature of EPDM rubber is considerably improved by the addition of LDH as realised by the observation of a shortening of the vulcanization time and an improvement of ultimate rheometric torque. This behavior of LDH signifies not only the filler-like character of itself, but also offers vulcanization active surface properties of layered double hydroxide particles. A good rubber-filler interaction was also realised by observing a positive shift of the glass transition temperature of ethylene propylene diene rubber (EPDM) in dynamic mechanical analysis (DMA). The flame retardant property was studied by the cone calorimeter test. The cone calorimeter investigation with sulfur cured gum rubber compounds found a peak heat release rate (PHRR) value of 654 kW m-2. However, at a higher phr loading of Zn-Al LDH i.e., at 40 phr and 100 phr, the PHRR is diminished to 311 kW m-2 and 161 kW m-2, respectively. Thus, this present work can pave the way to fabricate environmentally friendly fire retardant elastomeric composites for various applications.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Materials Science, Research group: Plastics and Elastomer Technology, Institut für Werkstoffwissenschaft, Leibniz-Institut für Polymerforschung Dresden E.V., IMDEA Materials Institute, Cochin University of Science and Technology
Contributors: Basu, D., Das, A., Wang, D. Y., George, J. J., Stöckelhuber, K. W., Boldt, R., Leuteritz, A., Heinrich, G.
Number of pages: 12
Pages: 26425-26436
Publication date: 2016
Peer-reviewed: Yes

Publication information

Journal: RSC Advances
Volume: 6
Issue number: 31
ISSN (Print): 2046-2069
Ratings: 
  • Scopus rating (2016): CiteScore 4.1 SJR 0.889 SNIP 0.757
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all), Chemistry(all)
Source: Scopus
Source ID: 84961194468

Research output: Contribution to journalArticleScientificpeer-review

Functional model for organisational and safety culture

Cultures are usually defined as shared values, attitudes and behaviour of certain group. The core of culture is inside person's mind. Only through behaviour or other actions of persons the culture becomes visible and shareable. Cultural artefacts and all other perceptible signs of culture are formed through action. From this perspective culture requires functionality. It does not exist nor spread without activity of individuals. In systems theory there is a methodological distinction between theoretical system and empirical system. Theoretical system "is a complex of concepts, suppositions, and propositions having both logical integration and empirical reference". Empirical system is "a set of phenomena in the observable world that is amenable to description and analysis by means of a theoretical system". However, in cultural context, theoretical models usually describe only properties of the empirical system. Usually the functionality of the culture is left undefined. Therefore theoretical models may have flaws in their ability to describe the functionality of the culture, which is essential part of the culture. In this paper we use a novel functional model to explore the functionality of the most commonly used culture models. We inspect Schein's organizational culture model, Cooper's reciprocal safety culture model and Johnson's cultural web. We study them and their functionality with our own functional model, which integrates person to sociotechnical system and shows person-sociotechnical system interaction. This study clearly shows that if culture's basis is in shared mental models, then the question whether organization is or has culture is absurd. As Antonsen has pointed out certain mandatory organizational features are clearly structural and not cultural. We also emphasize the behavioural aspect when defining cultural issues. The shared mental model alone is not sufficient requirement to define a feature as a cultural artefact, nor is the behaviour all employees share. Behaviour or action is cultural artefact only when the members of the culture have truly free will to choose their behaviour.

General information

Publication status: Published
MoE publication type: A3 Part of a book or another research book
Organisations: Pori Department
Contributors: Porkka, P. L.
Number of pages: 6
Pages: 907-912
Publication date: 2016

Host publication information

Title of host publication: Chemical Engineering Transactions
Publisher: Italian Association of Chemical Engineering AIDIC
ISBN (Print): 9788895608396

Publication series

Name: Chemical Engineering Transactions
Volume: 48
ISSN (Electronic): 2283-9216
ASJC Scopus subject areas: Chemical Engineering(all)

Bibliographical note

JUFOID=70222

Source: Scopus
Source ID: 84976878615

Research output: Chapter in Book/Report/Conference proceedingChapterScientificpeer-review

High-Yield Excited Triplet States in Pentacene Self-Assembled Monolayers on Gold Nanoparticles through Singlet Exciton Fission

One of the major drawbacks of organic-dye-modified self-assembled monolayers on metal nanoparticles when employed for efficient use of light energy is the fact that singlet excited states on dye molecules can be easily deactivated by means of energy transfer to the metal surface. In this study, a series of 6,13-bis(triisopropylsilylethynyl)pentacene-alkanethiolate monolayer protected gold nanoparticles with different particle sizes and alkane chain lengths were successfully synthesized and were employed for the efficient generation of excited triplet states of the pentacene derivatives by singlet fission. Time-resolved transient absorption measurements revealed the formation of excited triplet states in high yield (172±26%) by suppressing energy transfer to the gold surface.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Supramolecular photochemistry, Keio University
Contributors: Kato, D., Sakai, H., Tkachenko, N. V., Hasobe, T.
Pages: 5230-5234
Publication date: 2016
Peer-reviewed: Yes

Publication information

Journal: Angewandte Chemie (International Edition)
Volume: 55
Issue number: 17
ISSN (Print): 1433-7851
Ratings: 
  • Scopus rating (2016): CiteScore 18.7 SJR 5.954 SNIP 2.185
Original language: English
ASJC Scopus subject areas: Chemistry(all), Catalysis
Keywords: Gold, Nanoparticles, Pentacene, Self-assembled monolayers, Singlet fission
Source: Scopus
Source ID: 84961773531

Research output: Contribution to journalArticleScientificpeer-review

Metrics for polyphonic sound event detection

This paper presents and discusses various metrics proposed for evaluation of polyphonic sound event detection systems used in realistic situations where there are typically multiple sound sources active simultaneously. The system output in this case contains overlapping events, marked as multiple sounds detected as being active at the same time. The polyphonic system output requires a suitable procedure for evaluation against a reference. Metrics from neighboring fields such as speech recognition and speaker diarization can be used, but they need to be partially redefined to deal with the overlapping events. We present a review of the most common metrics in the field and the way they are adapted and interpreted in the polyphonic case. We discuss segment-based and event-based definitions of each metric and explain the consequences of instance-based and class-based averaging using a case study. In parallel, we provide a toolbox containing implementations of presented metrics.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Signal Processing, Research group: Audio research group
Contributors: Mesaros, A., Heittola, T., Virtanen, T.
Publication date: 2016
Peer-reviewed: Yes

Publication information

Journal: Applied Sciences
Volume: 6
Issue number: 6
Article number: 162
ISSN (Print): 2076-3417
Ratings: 
  • Scopus rating (2016): SJR 0.315 SNIP 0.791
Original language: English
ASJC Scopus subject areas: Fluid Flow and Transfer Processes, Process Chemistry and Technology, Computer Science Applications, Engineering(all), Materials Science(all), Instrumentation
Keywords: Audio content analysis, Audio signal processing, Computational auditory scene analysis, Evaluation of sound event detection, Everyday sounds, Pattern recognition, Polyphonic sound event detection, Sound events
Source: Scopus
Source ID: 84973574836

Research output: Contribution to journalArticleScientificpeer-review

Nanoscale barrier coating on BOPP packaging film by ALD

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Materials Science, Research group: Paper Converting and Packaging
Contributors: Lahti, J.
Number of pages: 13
Pages: 493-505
Publication date: 2016

Host publication information

Title of host publication: TAPPI PLACE Conference 2016: Exploring New Frontiers
Publisher: TAPPI Press
ISBN (Electronic): 9781510823563
ASJC Scopus subject areas: Media Technology, Mechanical Engineering, Materials Science(all), Chemistry(all), Chemical Engineering(all)
Source: Scopus
Source ID: 84981736600

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Nonlinear transmittance and optical power limiting in magnesium ferrite nanoparticles: effects of laser pulsewidth and particle size

We report comparative measurements of size dependent nonlinear transmission and optical power limiting in nanocrystalline magnesium ferrite (MgFe2O4) particles excited by short (nanosecond) and ultrashort (femtosecond) laser pulses. A standard sol-gel technique is employed to synthesize particles in the size range of 10-50 nm, using polyvinyl alcohol as the chelating agent. The structure and morphology of the samples are studied using X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Growth of the particles in time is tracked through Fourier transform infrared spectroscopy. Nonlinear transmission measurements have been carried out using the open aperture Z-scan technique employing 532 nm, 5 nanosecond pulses and 800 nm, 100 femtosecond pulses, respectively. The measured optical nonlinearity is primarily of a reverse saturable absorption (RSA) nature, arising mostly from excited state absorption for nanosecond excitation, and two-photon absorption for femtosecond excitation. The optical limiting efficiency is found to increase with particle size for both cases. The calculated nonlinear parameters indicate that these materials are potential candidates for optical limiting applications.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Photonics, National Institute of Technology Karnataka, International and Inter University Centre for Nanoscience and Nanotechnology, Mahatma Gandhi University, Raman Research Institute
Contributors: Perumbilavil, S., Sridharan, K., Abraham, A. R., Janardhanan, H. P., Kalarikkal, N., Philip, R.
Number of pages: 8
Pages: 106754-106761
Publication date: 2016
Peer-reviewed: Yes

Publication information

Journal: RSC Advances
Volume: 6
Issue number: 108
ISSN (Print): 2046-2069
Ratings: 
  • Scopus rating (2016): CiteScore 4.1 SJR 0.889 SNIP 0.757
Original language: English
ASJC Scopus subject areas: Chemistry(all), Chemical Engineering(all)
Source: Scopus
Source ID: 84995977139

Research output: Contribution to journalArticleScientificpeer-review

Optimal short distance electrode locations for impedance pneumography measurement from the frontal thoracic area

Electrical impedance pneumography signal is a valuable tool in qualifying better the person’s health condition. It can be used in monitoring of respiration rate, rhythm and tidal volume. Impedance pneumography has also the potential in ambulatory physiological monitoring systems that are increasingly often implemented using plaster-like on-body devices. In such cases, the area of electrode substrate may be limited and therefore, the electrode configuration, which is able to provide both a clinically valuable electrocardiogram signal and accurate pulmonary information, is an issue. EAS is a useful small area electrode configuration that can be used for electrocardiogram measurements. In this work, different two-electrode bipolar pairs of EAS system are tested for impedance pneumography measurements. Two additional electrodes are also considered in these tests. Our results show that the electrode pair S-A provides the most accurate respiration cycle length and is least affected by movement artifact. Additionally, the results show that this electrode pair produces the signals with highest amplitude.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Electronics and Communications Engineering, Research group: Laboratory for Future Electronics, Department of Automation Science and Engineering, Research area: Microsystems, Research area: Measurement Technology and Process Control, University of Oulu
Contributors: Jeyhani, V., Vuorinen, T., Noponen, K., Mäntysalo, M., Vehkaoja, A.
Number of pages: 6
Pages: 1138-1143
Publication date: 2016

Host publication information

Title of host publication: XIV Mediterranean Conference on Medical and Biological Engineering and Computing 2016 : MEDICON 2016, March 31st-April 2nd 2016, Paphos, Cyprus
Publisher: Springer Verlag
ISBN (Print): 9783319327013

Publication series

Name: IFMBE Proceedings
Volume: 57
ISSN (Print): 1680-0737
ASJC Scopus subject areas: Biomedical Engineering, Bioengineering
Keywords: Electrode, Impedance, Location, Pneumography, Respiration

Bibliographical note

INT=ase,"Jeyhani, Vala"
JUFOID=58152

Source: Scopus
Source ID: 84968593202

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Preferential adsorption of Cu in a multi-metal mixture onto biogenic elemental selenium nanoparticles

Preferential adsorption of Cu contained in wastewaters is desirable as the Cu can then be reprocessed and reused more easily. In this study, biogenic elemental selenium nanoparticles (BioSeNPs) were assessed for their ability to preferentially adsorb Cu from an equimolar mixture containing Cu, Cd and Zn. Variations in metal to BioSeNPs ratios and initial metal solution pH improved the preferential adsorption capacity of BioSeNPs toward Cu, with the ratio of Cu adsorbed to combined Cd and Zn adsorbed varying from 2.3 to 6.6. More than 78% of the added Cu was adsorbed at an initial metal solution pH of 5.2 and metal to BioSeNPs ratio of 0.21mgmg-1 when the ratio of Cu adsorbed to the sum of Cd and Zn adsorbed was 2.3. Infrared spectroscopy revealed that the Cu, Cd and Zn were interacting with the hydroxyl and carboxyl surface functional groups of the BioSeNPs. The modeling of BioSeNPs' acid-base titration revealed the presence of high concentrations of carboxylic groups (C=60.3molkg-1) with a pKa of 3.9, providing further evidence of their interaction with Cu. The adsorption of Cu resulted in a lower colloidal stability of the BioSeNPs as indicated by more than 99% retention of added BioSeNPs after adsorption of heavy metals and filtration. BioSeNPs showed a good preferential adsorption capacity toward Cu as compared to other adsorbent. This study provides a proof-of-concept for the preferential adsorption of Cu onto BioSeNPs which are present in the effluent of a bioreactor treating selenium oxyanions containing wastewater.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Tampere University of Technology, Research group: Industrial Bioengineering and Applied Organic Chemistry, Université Paris-Est
Contributors: Jain, R., Dominic, D., Jordan, N., Rene, E. R., Weiss, S., van Hullebusch, E. D., Hübner, R., Lens, P. N. L.
Pages: 917–925
Publication date: 2016
Peer-reviewed: Yes
Early online date: 2015

Publication information

Journal: Chemical Engineering Journal
Volume: 284
ISSN (Print): 1385-8947
Ratings: 
  • Scopus rating (2016): CiteScore 9.7 SJR 1.758 SNIP 1.952
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all), Chemistry(all), Industrial and Manufacturing Engineering, Environmental Chemistry
Keywords: Biogenic, Copper, FT-IR, Heavy metals, Preferential adsorption, Selenium nanoparticles
Source: Scopus
Source ID: 84942540702

Research output: Contribution to journalArticleScientificpeer-review

Remarkable Dependence of the Final Charge Separation Efficiency on the Donor-Acceptor Interaction in Photoinduced Electron Transfer

The unprecedented dependence of final charge separation efficiency as a function of donor-acceptor interaction in covalently-linked molecules with a rectilinear rigid oligo-p-xylene bridge has been observed. Optimization of the donor-acceptor electronic coupling remarkably inhibits the undesirable rapid decay of the singlet charge-separated state to the ground state, yielding the final long-lived, triplet charge-separated state with circa 100% efficiency. This finding is extremely useful for the rational design of artificial photosynthesis and organic photovoltaic cells toward efficient solar energy conversion.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Supramolecular photochemistry, Kyoto Women's University, Tokushima University, Kobe University, Japan Science and Technology Agency, University of Tokyo
Contributors: Higashino, T., Yamada, T., Yamamoto, M., Furube, A., Tkachenko, N. V., Miura, T., Kobori, Y., Jono, R., Yamashita, K., Imahori, H.
Pages: 629-633
Publication date: 2016
Peer-reviewed: Yes

Publication information

Journal: Angewandte Chemie (International Edition)
Volume: 55
Issue number: 2
ISSN (Print): 1433-7851
Ratings: 
  • Scopus rating (2016): CiteScore 18.7 SJR 5.954 SNIP 2.185
Original language: English
ASJC Scopus subject areas: Chemistry(all), Catalysis
Keywords: Charge separation, Electron transfer, Electronic coupling, Exciplexes, Marcus theory
Source: Scopus
Source ID: 84958749577

Research output: Contribution to journalArticleScientificpeer-review

Roll-to-roll application of photocatalytic TiO2 nanoparticles for printed functionality

In this work ultraviolet A (UVA) light controlled photocatalytic activity of TiO2 nanoparticles is utilized on paper, paperboard, and plastic films for controlled wetting and oxygen sensors for modified atmosphere packages (MAPs). A liquid flame spray (LFS) process is used for a large-area TiO2 nanoparticle deposition on natural fibre based substrates such as paperboard that results in a superhydrophobic surface. Controlled wettability is achieved using an UVA light activation that converts the surface to hydrophilic whereas an oven heat treatment recovers the initial superhydrophobicity. On the other hand, a TiO2 nanoparticles with methylene blue (MB) dye is used to detect the presence of oxygen in modified atmosphere packages. We believe that photocatalytically active surfaces with tailorable properties will find many applications in the near future, for example, with printed functional devices.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Physics, Research area: Aerosol Physics, Research group: Aerosol Synthesis, Center for Functional Materials at Biological Interfaces (FUNMAT), Abo Akad Univ, Abo Akademi University, Dept Phys, Omya International AG, AGH University of Science and Technology, Aerosol Physics Laboratory
Contributors: Saarinen, J. J., Valtakari, D., Bollström, R., Stepien, M., Haapanen, J., Mäkelä, J. M., Toivakka, M.
Number of pages: 4
Pages: 47-50
Publication date: 2016

Host publication information

Title of host publication: Advanced Manufacturing, Electronics and Microsystems : TechConnect Briefs 2016
Volume: 4
Publisher: TechConnect
ISBN (Electronic): 9780997511734
ASJC Scopus subject areas: Fluid Flow and Transfer Processes, Biotechnology, Surfaces, Coatings and Films, Fuel Technology
Keywords: Controlled wetting, Nanoparticles, O sensor, Photocatalysis, TiO
Source: Scopus
Source ID: 84988974879

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Superfluorinated Ionic Liquid Crystals Based on Supramolecular, Halogen-Bonded Anions

Unconventional ionic liquid crystals in which the liquid crystallinity is enabled by halogen-bonded supramolecular anions [CnF2n+1-I···I···I-CnF2n+1]- are reported. The material system is unique in many ways, demonstrating for the first time 1)ionic, halogen-bonded liquid crystals, and 2)imidazolium-based ionic liquid crystals in which the occurrence of liquid crystallinity is not driven by the alkyl chains of the cation.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Supramolecular photochemistry
Contributors: Cavallo, G., Terraneo, G., Monfredini, A., Saccone, M., Priimägi, A., Pilati, T., Resnati, G., Metrangolo, P., Bruce, D. W.
Pages: 6300-6304
Publication date: 2016
Peer-reviewed: Yes

Publication information

Journal: Angewandte Chemie (International Edition)
Volume: 55
Issue number: 21
ISSN (Print): 1433-7851
Ratings: 
  • Scopus rating (2016): CiteScore 18.7 SJR 5.954 SNIP 2.185
Original language: English
ASJC Scopus subject areas: Chemistry(all), Catalysis
Keywords: Fluorophobic effect, Halogen bonding, Ionic liquid crystals, Self-assembly, Supramolecular chemistry
Source: Scopus
Source ID: 84979722901

Research output: Contribution to journalArticleScientificpeer-review

Two models for hydraulic cylinders in flexible multibody simulations

In modelling hydraulic cylinders interaction between the structural response and the hydraulic system needs to be taken into account. In this chapter two approaches for modelling flexible multibody systems coupled with hydraulic actuators i.e. cylinders are presented and compared. These models are the truss-elementlike cylinder and bending flexible cylinder models. The bending flexible cylinder element is a super-element combining the geometrically exact Reissner-beam element, the C1-continuous slide-spring element needed for the telescopc movement and the hydraulic fluid field. Both models are embeded with a friction model based on a bristle approach. The models are implemented in a finite element enviroment. In time the coupled stiff differential equation system is integrated using the L-stable Rosenbrock method.

General information

Publication status: Published
MoE publication type: A3 Part of a book or another research book
Organisations: Department of Civil Engineering, Research group: Structural Mechanics, Department of Mechanical Engineering and Industrial Systems, Research area: Applied Mechanics, FS Dynamics Finland Oy Ab
Contributors: Ylinen, A., Mäkinen, J., Kouhia, R.
Number of pages: 31
Pages: 463-493
Publication date: 2016

Host publication information

Title of host publication: Computational Methods for Solids and Fluids : Multiscale Analysis, Probability Aspects and Model Reduction
Publisher: Springer
ISBN (Print): 978-3-319-27994-7
ISBN (Electronic): 978-3-319-27996-1

Publication series

Name: Computational Methods in Applied Sciences
Volume: 41
ISSN (Print): 1871-3033
ASJC Scopus subject areas: Computational Mathematics, Modelling and Simulation, Fluid Flow and Transfer Processes, Computer Science Applications, Civil and Structural Engineering, Electrical and Electronic Engineering, Biomedical Engineering

Bibliographical note

JUFOID=79940
EXT="Ylinen, Antti"

Source: Scopus
Source ID: 84964233721

Research output: Chapter in Book/Report/Conference proceedingChapterScientificpeer-review

X-ray microtomography of collagen and polylactide samples in liquids

Methods to image and assess the microstructure of polymer based biomaterials in liquid phase, for example cell culture medium, are well warranted. X-ray microtomography could provide a mean to visualize and analyze such structures. However, the density of such polymers is close to that of water and hence the inherent X-ray contrast is poor. The material can provide good contrast when dry, however, if the materials contain cells and are dried, the cell morphology may be distorted. Moreover the entire structure of these water containing materials are deformed in the drying process. In this paper we tested phosphotungstic acid (PTA) staining to improve the contrast. We imaged collagen and PLA samples, as well as collagen-PLA composites with μCT in air, water and alcohol. The methods were compared visually and with contrast to noise ratio calculated from the images. Our results demonstrate that with alcohol the PLA can be imaged also in liquid phase. PTA staining seems to be a good method to increase the contrast for collagen in μCT imaging.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Electronics and Communications Engineering, Research group: Biomaterials and Tissue Engineering Group, Research group: Computational Biophysics and Imaging Group
Contributors: Hannula, M., Haaparanta, A. M., Tamminen, I., Aula, A., Kellomäki, M., Hyttinen, J.
Number of pages: 5
Pages: 420-424
Publication date: 2016

Host publication information

Title of host publication: XIV Mediterranean Conference on Medical and Biological Engineering and Computing 2016 : MEDICON 2016, March 31st–April 2nd 2016, Paphos, Cyprus
Publisher: Springer Verlag
ISBN (Print): 9783319327013

Publication series

Name: IFMBE Proceedings
Volume: 57
ISSN (Print): 1680-0737
ASJC Scopus subject areas: Biomedical Engineering, Bioengineering
Keywords: Collagen, Polylactide, Staining, μCT imaging

Bibliographical note

JUFOID=58152

Source: Scopus
Source ID: 84968645247

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Importance of maintenance data quality in extended warranty simulation

As manufacturing industries are transforming towards service orientation, predicting the costs of product-service systems is becoming essential. Simulation is one possibility for evaluating the costs and risks involved in product-service systems, such as extended warranty agreements. We conducted a case study with a globally operating manufacturer of industrial goods who also provides services for the equipment. We created equipment performance simulation (EPSi) models and a tool, EPSitor, for using the models in predicting extended warranty costs. However, reliable simulation results require good quality maintenance and operation data from existing installations. We discovered that it is difficult to collect the data needed for simulations and there were many challenges with data quality. Quality problems were mainly observed in manually collected data. Insufficient data quality leads to a wider margin of error in the simulation models, which increases business risk. Identifying these challenges is the first step in transforming the data collection routines to support equipment performance simulations. The key to long-term business benefits of simulation is to acknowledge the importance of data quality and to establish efficient data collection routines. Future research should find ways to motivate maintenance technicians to collect good quality data. This would contribute to more accurate cost analysis and thus to better profitability of extended warranty contracts.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Mechanical Engineering and Industrial Systems, Research group: Käyttövarmuuden suunnittelu ja kunnossapito, Research area: Life-cycle Management, Aalto University
Contributors: Mahlamäki, K., Niemi, A., Jokinen, J., Borgman, J.
Number of pages: 8
Pages: 3-10
Publication date: 1 Jan 2016
Peer-reviewed: Yes

Publication information

Journal: International Journal of COMADEM
Volume: 19
Issue number: 1
ISSN (Print): 1363-7681
Ratings: 
  • Scopus rating (2016): CiteScore 0.2 SJR 0.128 SNIP 0.163
Original language: English
ASJC Scopus subject areas: Electrical and Electronic Engineering, Industrial and Manufacturing Engineering, Safety, Risk, Reliability and Quality, Bioengineering, Signal Processing, Strategy and Management
Keywords: Asset management, Data quality, Hitman factors

Bibliographical note

INT=mei,”Jokinen, Juuso”

Source: Scopus
Source ID: 84960940492

Research output: Contribution to journalArticleScientificpeer-review

Human Adipose Stem Cells Differentiated on Braided Polylactide Scaffolds is a Potential Approach for Tendon Tissue Engineering

Growing number of musculoskeletal defects increases the demand for engineered tendon. Our aim was to find an efficient strategy to produce tendon-like matrix in vitro. To allow efficient differentiation of human adipose stem cells (hASCs) toward tendon tissue, we tested different medium compositions, biomaterials, and scaffold structures in preliminary tests. This is the first study to report that medium supplementation with 50 ng/mL of growth and differentiation factor-5 (GDF-5) and 280 μM l-ascorbic acid are essential for tenogenic differentiation of hASCs. Tenogenic medium (TM) was shown to significantly enhance tendon-like matrix production of hASCs compared to other tested media groups. Cell adhesion, proliferation, and tenogenic differentiation of hASCs were supported on braided poly(l/d)lactide (PLA) 96l/4d copolymer filament scaffolds in TM condition compared to foamed poly(l-lactide-co-ε-caprolactone) (PLCL) 70L/30CL scaffolds. A uniform cell layer formed on braided PLA 96/4 scaffolds when hASCs were cultured in TM compared to maintenance medium (MM) condition after 14 days of culture. Furthermore, total collagen content and gene expression of tenogenic marker genes were significantly higher in TM condition after 2 weeks of culture. The elastic modulus of PLA 96/4 scaffold was more similar to the elastic modulus reported for native Achilles tendon. Our study showed that the optimized TM is needed for efficient and rapid in vitro tenogenic extracellular matrix production of hASCs. PLA 96/4 scaffolds together with TM significantly stimulated hASCs, thus demonstrating the potential clinical relevance of this novel and emerging approach to tendon injury treatments in the future.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Electronics and Communications Engineering, Research group: Biomaterials and Tissue Engineering Group, BioMediTech, Tampere University Hospital, Univ Helsinki, Helsinki University Central Hospital, University of Helsinki, Cent Hosp, Dept Med, Div Nephrol, University of Twente
Contributors: Vuornos, K., Björninen, M., Talvitie, E., Paakinaho, K., Kellomäki, M., Huhtala, H., Miettinen, S., Seppänen-Kaijansinkko, R., Haimi, S.
Number of pages: 11
Pages: 513-523
Publication date: 1 Mar 2016
Peer-reviewed: Yes

Publication information

Journal: Tissue Engineering Part A
Volume: 22
Issue number: 5-6
ISSN (Print): 1937-3341
Ratings: 
  • Scopus rating (2016): CiteScore 7.7 SJR 1.24 SNIP 0.988
Original language: English
ASJC Scopus subject areas: Bioengineering, Biochemistry, Biomedical Engineering, Biomaterials

Bibliographical note

EXT="Vuornos, Kaisa"

Source: Scopus
Source ID: 84961782193

Research output: Contribution to journalArticleScientificpeer-review

Metal chalcogenide quantum dots: Biotechnological synthesis and applications

Metal chalcogenide (metal sulfide, selenide and telluride) quantum dots (QDs) have attracted considerable attention due to their quantum confinement and size-dependent photoemission characteristics. QDs are one of the earliest products of nanotechnology that were commercialized for tracking macromolecules and imaging cells in life sciences. An array of physical, chemical and biological methods have been developed to synthesize different QDs. Biological production of QDs follow green chemistry principles, thereby use of hazardous chemicals, high temperature, high pressure and production of by-products is either minimized or completely avoided. In the past decade, significant progress has been made wherein a diverse range of living organisms, i.e. viruses, bacteria, fungi, microalgae, plants and animals have been explored for synthesis of all three types of metal chalcogenide QDs. However, better understanding of the biological mechanisms that mediate the synthesis of metal chalcogenides and control the growth of QDs is needed for improving their yield and properties as well as addressing issues that arise during scale-up. In this review, we present the current status of the biological synthesis and applications of metal chalcogenide QDs. Where possible, the role of key biological macromolecules in controlled production of the nanomaterials is highlighted, and also technological bottlenecks limiting widespread implementation are discussed. The future directions for advancing biological metal chalcogenide synthesis are presented.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry
Contributors: Mal, J., Nancharaiah, Y. V., Van Hullebusch, E. D., Lens, P. N. L.
Number of pages: 19
Pages: 41477-41495
Publication date: Apr 2016
Peer-reviewed: Yes

Publication information

Journal: RSC Advances
Volume: 6
Issue number: 47
ISSN (Print): 2046-2069
Ratings: 
  • Scopus rating (2016): CiteScore 4.1 SJR 0.889 SNIP 0.757
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all), Chemistry(all)
Source: Scopus
Source ID: 84966421058

Research output: Contribution to journalArticleScientificpeer-review

Effect of heavy metal co-contaminants on selenite bioreduction by anaerobic granular sludge

This study investigated bioreduction of selenite by anaerobic granular sludge in the presence of heavy metals and analyzed the fate of the bioreduced selenium and the heavy metals. Selenite bioreduction was not significantly inhibited in the presence of Pb(II) and Zn(II). More than 92% of 79 mg/L selenite was removed by bioreduction even in the presence of 150 mg/L of Pb(II) or 400 mg/L of Zn(II). In contrast, only 65-48% selenite was bioreduced in the presence of 150-400 mg/L Cd(II). Formation of elemental selenium or selenide varied with heavy metal type and concentration. Notably, the majority of the bioreduced selenium (70-90% in the presence of Pb and Zn, 50-70% in the presence of Cd) and heavy metals (80-90% of Pb and Zn, 60-80% of Cd) were associated with the granular sludge. The results have implications in the treatment of selenium wastewaters and biogenesis of metal selenides.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry, UPEM, Bhabha Atomic Research Centre, Environmental Engineering and Water Technology Department, UNESCO-IHE Institute for Water Education
Contributors: Mal, J., Nancharaiah, Y. V., van Hullebusch, E. D., Lens, P. N. L.
Number of pages: 8
Pages: 1-8
Publication date: 1 Apr 2016
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 206
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2016): CiteScore 9.9 SJR 2.215 SNIP 1.945
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Anaerobic granular sludge, Biosorption, Heavy metal removal, Metal selenide, Selenite bioreduction
Source: Scopus
Source ID: 84961305364

Research output: Contribution to journalArticleScientificpeer-review

Wetting hysteresis induced by temperature changes: Supercooled water on hydrophobic surfaces

The state and stability of supercooled water on (super)hydrophobic surfaces is crucial for low temperature applications and it will affect anti-icing and de-icing properties. Surface characteristics such as topography and chemistry are expected to affect wetting hysteresis during temperature cycling experiments, and also the freezing delay of supercooled water. We utilized stochastically rough wood surfaces that were further modified to render them hydrophobic or superhydrophobic. Liquid flame spraying (LFS) was utilized to create a multi-scale roughness by depositing titanium dioxide nanoparticles. The coating was subsequently made non-polar by applying a thin plasma polymer layer. As flat reference samples modified silica surfaces with similar chemistries were utilized. With these substrates we test the hypothesis that superhydrophobic surfaces also should retard ice formation. Wetting hysteresis was evaluated using contact angle measurements during a freeze-thaw cycle from room temperature to freezing occurrence at -7 °C, and then back to room temperature. Further, the delay in freezing of supercooled water droplets was studied at temperatures of -4 °C and -7 °C. The hysteresis in contact angle observed during a cooling-heating cycle is found to be small on flat hydrophobic surfaces. However, significant changes in contact angles during a cooling-heating cycle are observed on the rough surfaces, with a higher contact angle observed on cooling compared to during the subsequent heating. Condensation and subsequent frost formation at sub-zero temperatures induce the hysteresis. The freezing delay data show that the flat surface is more efficient in enhancing the freezing delay than the rougher surfaces, which can be rationalized considering heterogeneous nucleation theory. Thus, our data suggests that molecular flat surfaces, rather than rough superhydrophobic surfaces, are beneficial for retarding ice formation under conditions that allow condensation and frost formation to occur.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Physics, Research area: Aerosol Physics, Research group: Aerosol Synthesis, KTH Royal Institute of Technology, Surface and Corrosion Science, SP Technical Research Institute of Sweden, Department of Civil and Architectural Engineering, Nanostructure Physics
Contributors: Heydari, G., Sedighi Moghaddam, M., Tuominen, M., Fielden, M., Haapanen, J., Mäkelä, J. M., Claesson, P. M.
Number of pages: 13
Pages: 21-33
Publication date: 15 Apr 2016
Peer-reviewed: Yes

Publication information

Journal: Journal of Colloid and Interface Science
Volume: 468
ISSN (Print): 0021-9797
Ratings: 
  • Scopus rating (2016): CiteScore 7.2 SJR 1.156 SNIP 1.277
Original language: English
ASJC Scopus subject areas: Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Biomaterials, Colloid and Surface Chemistry
Keywords: Contact angle, Hydrophobization, Liquid flame spray (LFS), Morphology, Multi-scale roughness, Plasma polymerization, Supercooled water, Superhydrophobicity, Wetting hysteresis, Wood
Source: Scopus
Source ID: 84955276633

Research output: Contribution to journalArticleScientificpeer-review

Development of Magnetic Losses During Accelerated Corrosion Tests for Nd-Fe-B Magnets Used in Permanent Magnet Generators

Sintered Nd-Fe-B magnets are critical components in permanent magnet wind generators. They are the strongest permanent magnets available and thus enable the construction of light and effective devices, but their stability in corrosive environments is limited. In this work, the formation of corrosion losses in two types of Nd-Fe-B alloys was studied. Magnets were in a magnetized state during the corrosion test, enabling monitoring of the development of losses in magnetic flux along with those in weight. Parallel flux and weight loss measurements conducted during corrosion tests showed that percentage weight losses were lower than the total flux losses. Scanning electron microscope studies of corroded specimens disclosed that the magnets first underwent dissolution of the grain-boundary phase, followed by the detachment and movement of the loosened grains in the magnetic field. The degradation was accelerated by oxidation of the matrix phase, which introduced further damage by volume expansion.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Materials Science, Research group: Materials Characterization, VTT Technical Research Centre of Finland
Contributors: Isotahdon, E., Huttunen-Saarivirta, E., Kuokkala, V.
Number of pages: 10
Pages: 732-741
Publication date: 1 Jun 2016
Peer-reviewed: Yes

Publication information

Journal: Corrosion
Volume: 72
Issue number: 6
ISSN (Print): 0010-9312
Ratings: 
  • Scopus rating (2016): CiteScore 3.5 SJR 1.075 SNIP 1.488
Original language: English
ASJC Scopus subject areas: Materials Science(all), Chemical Engineering(all), Chemistry(all)
Keywords: Corrosion, Corrosion losses, Highly accelerated stress test (HAST test), Improved corrosion resistance sintered Nd-Fe-B magnets, Improved stability sintered Nd-Fe-B magnets, Nd-Fe-B, Permanent magnet, Scanning electron microscopy, Thermal losses, Wind power
Source: Scopus
Source ID: 84973626857

Research output: Contribution to journalArticleScientificpeer-review

Framework for optimization and scheduling of a copper production plant

This work presents a nonlinear optimization and scheduling approach applied to a copper production plant. The solution maximizes smelting furnace production and provides valid converting schedules by simulating the evolution of the process over the optimization horizon. The production process is briefly described and the main models used to predict and calculate furnace and converter parameters are detailed. Though the solution is concentrated on the main elements, copper and iron, the optimization framework enables easy future augmentation with more complex models. A schedule optimization case is presented.

General information

Publication status: Published
MoE publication type: A3 Part of a book or another research book
Organisations: Department of Automation Science and Engineering, Research area: Dynamic Systems, Research area: Measurement Technology and Process Control
Contributors: Suominen, O., Mörsky, V., Ritala, R., Vilkko, M.
Number of pages: 6
Pages: 1243-1248
Publication date: 25 Jun 2016

Host publication information

Title of host publication: 26th European Symposium on Computer Aided Process Engineering, 2016
Volume: 38
Publisher: Elsevier Science B.V.
ISBN (Print): 9780444634283

Publication series

Name: Computer Aided Chemical Engineering
ISSN (Print): 1570-7946
ASJC Scopus subject areas: Chemical Engineering(all), Computer Science Applications
Keywords: copper smelting, modelling, nonlinear optimization, Scheduling

Bibliographical note

JUFOID=70254

Source: Scopus
Source ID: 84994385954

Research output: Chapter in Book/Report/Conference proceedingChapterScientificpeer-review

Hydrothermal carbonization of pulp mill streams

The progress of the conversion, the yield, the structure and the morphology of the produced carbonaceous materials as a function of time were systematically studied with pyrolysis-GC/FID and FESEM microscope. The conversion of galactoglucomannan, bleached kraft pulp and TEMPO oxidized cellulose nanofibrils followed the reaction route of glucose being slower though with fibrous material, higher molar mass and viscosity. The conversion of kraft lignin was minor following completely different reaction route. Carbonaceous particles of different shape and size were produced with yields between 23% and 73% after 4 h with being higher for lignin than carbohydrates. According to the results, potential pulp mill streams represent lignocellulosic resources for generation of carbonaceous materials.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Materials Science, Research group: Materials Characterization, VTT Technical Research Centre of Finland
Contributors: Wikberg, H., Ohra-aho, T., Honkanen, M., Kanerva, H., Harlin, A., Vippola, M., Laine, C.
Number of pages: 9
Pages: 236-244
Publication date: 1 Jul 2016
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 212
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2016): CiteScore 9.9 SJR 2.215 SNIP 1.945
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Galactoglucomannan, Hydrothermal carbonization, Kraft lignin, Kraft pulp, Pulp mill

Bibliographical note

EXT="Harlin, Ali"

Source: Scopus
Source ID: 84963954557

Research output: Contribution to journalArticleScientificpeer-review

Modeling of the catalytic effects of potassium and calcium on spruce wood gasification in CO2

Using previously reported thermogravimetric analysis measurements, the effects of calcium and potassium on the char gasification rate of spruce wood were modeled. Spruce wood was leached of inorganic ash elements and doped with measured amounts of potassium and calcium. The wood was gasified in an isothermal thermogravimetric analysis device in CO2 where the devolatilization of the wood, char formation and char gasification all occurred inside the preheated reactor. A new method for separating the effects of devolatilization and char gasification is presented. Kinetic models were evaluated for their ability to describe the observed catalytic effects of potassium and calcium on the gasification rate. Two modified versions of the random pore model were able to accurately describe the measured conversion rates and the parameters of the kinetic models were found to be dependent on the calcium and potassium concentrations. Empirical correlations were developed to predict the char conversion rate from only the potassium and calcium concentration of the sample.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry, Johan Gadolin Process Chemistry Centre, Abo Akademi University, VTT Technical Research Centre of Finland
Contributors: Kramb, J., DeMartini, N., Perander, M., Moilanen, A., Konttinen, J.
Number of pages: 10
Pages: 50-59
Publication date: 1 Jul 2016
Peer-reviewed: Yes

Publication information

Journal: Fuel Processing Technology
Volume: 148
ISSN (Print): 0378-3820
Ratings: 
  • Scopus rating (2016): CiteScore 6.8 SJR 1.397 SNIP 1.769
Original language: English
ASJC Scopus subject areas: Fuel Technology, Energy Engineering and Power Technology, Chemical Engineering(all)
Keywords: Biomass, Gasification, Modeling, Reaction kinetics

Bibliographical note

EXT=”Moilanen, Antero"

Source: Scopus
Source ID: 84959431503

Research output: Contribution to journalArticleScientificpeer-review

Spontaneous formation of three-dimensionally ordered Bi-rich nanostructures within GaAs1-xBix/GaAs quantum wells

In this work, we report on the spontaneous formation of ordered arrays of nanometer-sized Bi-rich structures due to lateral composition modulations in Ga(As,Bi)/GaAs quantum wells grown by molecular beam epitaxy. The overall microstructure and chemical distribution is investigated using transmission electron microscopy. The information is complemented by synchrotron x-ray grazing incidence diffraction, which provides insight into the in-plane arrangement. Due to the vertical inheritance of the lateral modulation, the Bi-rich nanostructures eventually shape into a three-dimensional assembly. Whereas the Bi-rich nanostructures are created via two-dimensional phase separation at the growing surface, our results suggest that the process is assisted by Bi segregation which is demonstrated to be strong and more complex than expected, implying both lateral and vertical (surface segregation) mass transport. As demonstrated here, the inherent thermodynamic miscibility gap of Ga(As,Bi) alloys can be exploited to create highly uniform Bi-rich units embedded in a quantum confinement structure.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Optoelectronics Research Centre, Research group: Semiconductor Technology and Applications, Hausvogteiplatz 5-7
Contributors: Luna, E., Wu, M., Hanke, M., Puustinen, J., Guina, M., Trampert, A.
Publication date: 1 Jul 2016
Peer-reviewed: Yes

Publication information

Journal: Nanotechnology
Volume: 27
Issue number: 32
Article number: 325603
ISSN (Print): 0957-4484
Ratings: 
  • Scopus rating (2016): CiteScore 5.8 SJR 1.339 SNIP 0.982
Original language: English
ASJC Scopus subject areas: Bioengineering, Chemistry(all), Electrical and Electronic Engineering, Mechanical Engineering, Mechanics of Materials, Materials Science(all)
Keywords: GaAsBi, phase separation and segregation, self organization, TEM

Bibliographical note

EXT="Wu, M."

Source: Scopus
Source ID: 84978884196

Research output: Contribution to journalArticleScientificpeer-review

The influence of high-temperature sulfuric acid solution ageing on the properties of laminated vinyl-ester joints

A carbon fiber powder doped corrosion layer is used as an inner layer in large composite tanks to improve their chemical and wear resistance. In joints fabricated on site, this layer is embedded into the structure. This study evaluates the lap shear strength of specimens, simulating a laminated joint in between the corrosion layer and the inner joint laminate. Lap-shear tests were carried out for as-fabricated and aged laminates at room temperature and at elevated temperature. Ageing was carried out for half a year in a 95 °C pressurized sulfuric acid solution. The tests showed that, after ageing, the room temperature shear strength remained unaltered but high-temperature shear strength was lowered. When the temperature increased, the failure location shifted from the interface between the doped layer and the joint laminate to the doped layer. Thermal analysis and microscopy were employed to clarify the reasons for the observed behavior.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Materials Science, Research group: Plastics and Elastomer Technology, Outotec Research Center, Aalto University
Contributors: Lindgren, M., Wallin, M., Kakkonen, M., Saarela, O., Vuorinen, J.
Number of pages: 7
Pages: 298-304
Publication date: 1 Jul 2016
Peer-reviewed: Yes

Publication information

Journal: International Journal of Adhesion and Adhesives
Volume: 68
ISSN (Print): 0143-7496
Ratings: 
  • Scopus rating (2016): CiteScore 4 SJR 0.919 SNIP 1.516
Original language: English
ASJC Scopus subject areas: Chemical Engineering(all), Biomaterials, Polymers and Plastics
Keywords: Aging, Lap-shear, Sulfuric acid, Vinyl ester

Bibliographical note

EXT="Lindgren, M."

Source: Scopus
Source ID: 84973340146

Research output: Contribution to journalArticleScientificpeer-review

The Influence of Phosphorus Exposure on a Natural-Gas-Oxidation Catalyst

Phosphorus is found to have a deactivating effect on the catalytic activity of the studied natural-gas-oxidation catalyst. Accelerated laboratory-scale phosphorus treatment was done to the PtPd/Al2O3 natural gas oxidation catalyst. The effect of phosphorus after low (0.065 M) and high (0.13 M) phosphorus concentration treatments was studied by using an inductively coupled plasma optical emission spectroscopy, N2 physisorption, X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. In addition, the behavior of the catalyst was studied by a Gasmet FT-IR gas analyzer. Based on the received results it can be concluded that phosphorus was adsorbed on the surface by chemical bonds forming phosphates (PO4). In addition, the partial transformation of PdO to Pd was observed. Due to the phosphorus adsorption both the CO and CH4 oxidation activities were lower after the phosphorus treatments compared with the fresh catalyst.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Materials Science, Research group: Materials Characterization, University of Oulu, Aalto University, Dinex Ecocat Oy, COMP Centre of Excellence, Department of Applied Physics, Aalto University
Contributors: Kärkkäinen, M., Kolli, T., Honkanen, M., Heikkinen, O., Väliheikki, A., Huuhtanen, M., Kallinen, K., Lahtinen, J., Vippola, M., Keiski, R. L.
Number of pages: 5
Pages: 1044-1048
Publication date: 1 Jul 2016
Peer-reviewed: Yes

Publication information

Journal: Topics in Catalysis
Volume: 59
Issue number: 10-12
ISSN (Print): 1022-5528
Ratings: 
  • Scopus rating (2016): CiteScore 4.3 SJR 0.975 SNIP 0.855
Original language: English
ASJC Scopus subject areas: Catalysis, Chemistry(all)
Keywords: Methane degradation, Palladium, Platinum, Poisoning
Source: Scopus
Source ID: 84977071141

Research output: Contribution to journalArticleScientificpeer-review

Designing of Elastomer Nanocomposites: From Theory to Application


General information

Publication status: Published
MoE publication type: C2 Edited books
Organisations: Department of Materials Science, Research group: Plastics and Elastomer Technology, Leibniz-Institut für Polymerforschung Dresden E.V., Dt. Inst. für Kautschuktechnologie e.V.
Contributors: Stöckelhuber, K. W. (ed.), Das, A. (ed.), Klüppel, M. (ed.)
Publication date: 17 Aug 2016

Publication information

Publisher: Springer International Publishing
ISBN (Print): 9783319476957
ISBN (Electronic): 9783319476964
Original language: English

Publication series

Name: Advances in Polymer Science
Volume: 275
ISSN (Print): 0065-3195
ASJC Scopus subject areas: Chemical Engineering(all), Polymers and Plastics, Organic Chemistry
Keywords: Elastomers, Ionic crosslinking, Self healing rubber

Bibliographical note

JUFOID=50551

Research output: Book/ReportAnthologyScientificpeer-review

Nanostructured Ionomeric Elastomers

Driven by the desire to find an alternative way of vulcanizing elastomers without sulfur, researchers have widely explored ionic crosslinking techniques. The opportunity was taken to play with the functionality of the host polymer and its modification process to develop nanostructured ionic elastomers. Neutralization of polar elastomers by various divalent metal cations has been the route most employed for fabrication of this class of material. Ionic association or aggregation on the molecular level results in microphase separation of certain regions and, hence, enables easier processing. Thermally labile ionic domains introduced into the network make the entire material thermoresponsive and, therefore, it is possible to obtain reversible transition of dynamic mechanical properties. The unique network structure of these materials has led to outstanding physical properties that have not been achieved so far for conventional sulfidic networks. Consequently, many multifunctional and smart materials have been envisaged and designed using these systems. A detailed overview is provided on the various nanostructured ionic elastomers developed over the years. It would not be exaggerating to mention in the context of the discussion that nanostructured ionic elastomers will definitely open up new horizons in materials research.

General information

Publication status: Published
MoE publication type: A3 Part of a book or another research book
Organisations: Department of Materials Science, Research group: Plastics and Elastomer Technology, Apollo Tyres Limited, Leibniz-Institut für Polymerforschung Dresden E.V., Vodafone Department of Mobile Communications Systems
Contributors: Basu, D., Das, A., Stöckelhuber, K. W., Wießner, S.
Number of pages: 32
Pages: 235-266
Publication date: 17 Aug 2016

Host publication information

Title of host publication: Designing of Elastomer Nanocomposites: From Theory to Applications
Publisher: Springer International Publishing
Editors: Stöckelhuber, K. W., Das, A., Klüppel, M.
ISBN (Print): 9783319476957
ISBN (Electronic): 9783319476964

Publication series

Name: Advances in Polymer Science
Volume: 275
ISSN (Print): 0065-3195
ASJC Scopus subject areas: Chemical Engineering(all), Polymers and Plastics, Organic Chemistry
Keywords: Elastomers, Ionic crosslinking, Self healing rubber

Bibliographical note

JUFOID=50551

Source: Scopus
Source ID: 84994670333

Research output: Chapter in Book/Report/Conference proceedingChapterScientificpeer-review

Recent advances in nutrient removal and recovery in biological and bioelectrochemical systems

Nitrogen and phosphorous are key pollutants in wastewater to be removed and recovered for sustainable development. Traditionally, nitrogen removal is practiced through energy intensive biological nitrification and denitrification entailing a major cost in wastewater treatment. Recent innovations in nitrogen removal aim at reducing energy requirements and recovering ammonium nitrogen. Bioelectrochemical systems (BES) are promising for recovering ammonium nitrogen from nitrogen rich waste streams (urine, digester liquor, swine liquor, and landfill leachate) profitably. Phosphorus is removed from the wastewater in the form of polyphosphate granules by polyphosphate accumulating organisms. Alternatively, phosphorous is removed/recovered as Fe-P or struvite through chemical precipitation (iron or magnesium dosing). In this article, recent advances in nutrients removal from wastewater coupled to recovery are presented by applying a waste biorefinery concept. Potential capabilities of BES in recovering nitrogen and phosphorous are reviewed to spur future investigations towards development of nutrient recovery biotechnologies.

General information

Publication status: Published
MoE publication type: A2 Review article in a scientific journal
Organisations: Department of Chemistry and Bioengineering
Contributors: Nancharaiah, Y. V., Venkata Mohan, S., Lens, P. N. L.
Pages: 173–185
Publication date: Sep 2016
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 215
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2016): CiteScore 9.9 SJR 2.215 SNIP 1.945
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Microbial fuel cells, Nitrogen removal, Phosphorus removal, Waste biorefinery, Wastewater
Source: Scopus
Source ID: 84962019395

Research output: Contribution to journalReview ArticleScientificpeer-review

3D micro-nano structured hybrid scaffolds: An investigation into the role of nanofiber coating on viability, proliferation and differentiation of seeded mesenchymal stem cells

The introduction of a three dimensional scaffold providing the closest analogies to extracellular matrix (ECM) is currently a key strategy for tackling many challenges in tissue repair. Here, we present a new hybrid scaffold constructed by coating electrospun chitosan/polyethylene oxide (PEO) nanofibers on commercial BioTek polystyrene (PS) scaffold obtained from Sigma Aldrich. The viability and proliferation rate of mesenchymal stem cells (MSCs) seeded on micro-nano structured hybrid scaffold (MNHS) and commercial PS scaffolds were analyzed by MTT assay. The results of the MTT assay revealed a higher degree of viability and proliferation rate in MSCs seeded on MNHS compared with the commercial PS scaffold. DAPI images also confirmed the higher degree of attachment and viability of MSCs seeded on MNHS. Moreover, MSCs on both scaffolds differentiated to osteoblasts and adipocytes cells, as reflected by the images obtained from Alizarin Red and Oil Red-O staining. Alkaline phosphatase activity (ALP) and calcium content assays revealed that the MNHS has a higher potential for osteogenic differentiation than the commercial scaffold. To quantify the osteoblast and adipocyte gene expression, quantitative RT-PCR was carried out for MNHS, commercial scaffold and Tissue culture polystyrene (TCPS). It was found that MNHS can express a higher level of Runt-related transcription factor 2 (Runx2), osteonectin and osteocalcin in osteogenic differentiation as well as increased expression of PPARγ and UCP-1 in adipogenic differentiation. The enhancement of the attachment, viability and proliferation as well as bi-lineage differentiation may result from the biochemical and structural analogies of MNHS to native ECM. Furthermore, it was observed that biocompatible MNHS scaffold can potentially be utilized as a suitable scaffold for bone and connective tissue engineering.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Materials Science, Research group: Fibre Materials, Tarbiat Modares University, Isfahan University of Medical Sciences, VTT Technical Research Centre of Finland
Contributors: Pilehrood, M. K., Atashi, A., Sadeghi-Aliabadi, H., Nousiainen, P., Harlin, A.
Number of pages: 8
Pages: 9000-9007
Publication date: 1 Sep 2016
Peer-reviewed: Yes

Publication information

Journal: Journal Nanoscience and Nanotechnology
Volume: 16
Issue number: 9
ISSN (Print): 1533-4880
Ratings: 
  • Scopus rating (2016): CiteScore 2.3 SJR 0.324 SNIP 0.486
Original language: English
ASJC Scopus subject areas: Bioengineering, Chemistry(all), Biomedical Engineering, Materials Science(all), Condensed Matter Physics
Keywords: Adipogenic Differentiation, Hybrid Scaffold, Mesenchymal Stem Cell, Micro Porosity, Nanofiber, Osteogenic Differentiation

Bibliographical note

EXT="Harlin, Ali"

Source: Scopus
Source ID: 84983416664

Research output: Contribution to journalArticleScientificpeer-review

Long-term stability of bioelectricity generation coupled with tetrathionate disproportionation

To prevent uncontrolled acidification of the environment, reduced inorganic sulfur compounds (RISCs) can be bioelectrochemically removed from water streams. The long-term stability of bioelectricity production from tetrathionate (S4O6 2-) was studied in highly acidic conditions (pH <2.5) in two-chamber fed-batch microbial fuel cells (MFCs). The maximum current density was improved from previously reported 80 mA m-2 to 225 mA m-2 by optimizing the external resistance. The observed reaction products of tetrathionate disproportionation were sulfate and elemental sulfur. In long-term run, stable electricity production was obtained for over 700 days with the average current density of 150 mA m-2. The internal resistance of the MFC decreased over time and no biofouling was observed. This study shows that tetrathionate is an efficient substrate also for long-term bioelectricity production.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry
Contributors: Sulonen, M. L. K., Lakaniemi, A. M., Kokko, M. E., Puhakka, J. A.
Number of pages: 7
Pages: 876-882
Publication date: 1 Sep 2016
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 216
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2016): CiteScore 9.9 SJR 2.215 SNIP 1.945
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Acidophile, Disproportionation, Long-term stability, Microbial fuel cell, Tetrathionate
Source: Scopus
Source ID: 84974777755

Research output: Contribution to journalArticleScientificpeer-review

Elimination of arsenic-containing emissions from gasification of chromated copper arsenate wood

The behavior of arsenic in chromated copper arsenate containing wood during gasification was modeled using thermodynamic equilibrium calculations. The results of the model were validated using bench-scale gasification tests. It is shown that over 99.6% of arsenic can be removed from the product gas by a hot filter when the gas is cooled below the predicted condensation temperature.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry, Energy Technology and Thermal Process Chemistry, Gasification Technologies Inc., Gas Technology Institute
Contributors: Kramb, J., Konttinen, J., Backman, R., Salo, K., Roberts, M.
Number of pages: 6
Pages: 319-324
Publication date: 1 Oct 2016
Peer-reviewed: Yes

Publication information

Journal: Fuel
Volume: 181
ISSN (Print): 0016-2361
Ratings: 
  • Scopus rating (2016): CiteScore 7.8 SJR 1.736 SNIP 2.206
Original language: English
ASJC Scopus subject areas: Fuel Technology, Energy Engineering and Power Technology, Chemical Engineering(all), Organic Chemistry
Keywords: Arsenic, CCA wood, Equilibrium modeling, Gasification
Source: Scopus
Source ID: 84965081806

Research output: Contribution to journalArticleScientificpeer-review

Increased survival rate by local release of diclofenac in a murine model of recurrent oral carcinoma

Despite aggressive treatment with radiation and combination chemotherapy following tumor resection, the 5-year survival rate for patients with head and neck cancer is at best only 50%. In this study, we examined the therapeutic potential of localized release of diclofenac from electrospun nanofibers generated from poly(d,l-lactide-co-glycolide) polymer. Diclofenac was chosen since anti-inflammatory agents that inhibit cyclooxygenase have shown great potential in their ability to directly inhibit tumor growth as well as suppress inflammation-mediated tumor growth. A mouse resection model of oral carcinoma was developed by establishing tumor growth in the oral cavity by ultrasound-guided injection of 1 million SCC-9 cells in the floor of the mouth. Following resection, mice were allocated into four groups with the following treatment: 1) no treatment, 2) implanted scaffolds without diclofenac, 3) implanted scaffolds loaded with diclofenac, and 4) diclofenac given orally. Small animal ultrasound and magnetic resonance imaging were utilized for longitudinal determination of tumor recurrence. At the end of 7 weeks following tumor resection, 33% of mice with diclofenac-loaded scaffolds had a recurrent tumor, in comparison to 90%-100% of the mice in the other three groups. At this time point, mice with diclofenac-releasing scaffolds showed 89% survival rate, while the other groups showed survival rates of 10%-25%. Immunohistochemical staining of recurrent tumors revealed a near 10-fold decrease in the proliferation marker Ki-67 in the tumors derived from mice with diclofenac-releasing scaffolds. In summary, the local application of diclofenac in an orthotopic mouse tumor resection model of oral cancer reduced tumor recurrence with significant improvement in survival over a 7-week study period following tumor resection. Local drug release of anti-inflammatory agents should be investigated as a therapeutic option in the prevention of tumor recurrence in oral squamous carcinoma.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Electronics and Communications Engineering, Clinic for Radiology and Neuroradiology, University Hospital Schleswig-Holstein, Institute of Biochemistry, University Hospital Cologne
Contributors: Will, O. M., Purcz, N., Chalaris, A., Heneweer, C., Boretius, S., Purcz, L., Nikkola, L., Ashammakhi, N., Kalthoff, H., Glüer, C. C., Wiltfang, J., Açil, Y., Tiwari, S.
Number of pages: 11
Pages: 5311-5321
Publication date: 12 Oct 2016
Peer-reviewed: Yes

Publication information

Journal: International Journal of Nanomedicine
Volume: 11
ISSN (Print): 1176-9114
Ratings: 
  • Scopus rating (2016): CiteScore 7 SJR 1.174 SNIP 1.211
Original language: English
ASJC Scopus subject areas: Bioengineering, Biophysics, Biomaterials, Drug Discovery, Organic Chemistry
Keywords: Drug releasing polymers, Head and neck cancer, Mouse model, NSAIDs, Oral squamous cell carcinoma, Tumor recurrence
Source: Scopus
Source ID: 84991726470

Research output: Contribution to journalArticleScientificpeer-review

Grain orientation dependent Nb-Ti microalloying mediated surface segregation on ferritic stainless steel

Surface segregation and oxide formation anisotropy on Ti-Nb stabilized ferritic stainless steel (EN 1.4521) were studied by XPS and Electron Backscatter Diffraction. Competitive surface segregation of Si, Nb and Ti was initiated at ∼550. °C, and segregation was favored to the open surface sites of 〈111〉 oriented grains. Furthermore, the surface segregation of Cr was strongly limited at the locations of stable Ti(CN)- and (NbTi)C-type precipitates. Consequently, the oxidation resistance of stainless steels can be enhanced cost-efficiently, without alloy additions, by optimizing the microstructure to facilitate the fast and uniform growth of protective oxide scale.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Optoelectronics Research Centre, Research group: Surface Science, Department of Materials Science, Research group: Materials Characterization
Contributors: Ali-Löytty, H., Hannula, M., Honkanen, M., Östman, K., Lahtonen, K., Valden, M.
Pages: 204-213
Publication date: Nov 2016
Peer-reviewed: Yes

Publication information

Journal: Corrosion Science
Volume: 112
ISSN (Print): 0010-938X
Ratings: 
  • Scopus rating (2016): CiteScore 9.6 SJR 1.891 SNIP 2.467
Original language: English
ASJC Scopus subject areas: Materials Science(all), Chemical Engineering(all), Chemistry(all)
Keywords: A. Stainless steel, B. SEM, B. XPS, C. Interfaces, C. Oxidation, C. Segregation
Source: Scopus
Source ID: 84979753478

Research output: Contribution to journalArticleScientificpeer-review

Magnesium aminoclay enhances lipid production of mixotrophic Chlorella sp. KR-1 while reducing bacterial populations

Improving lipid productivity and preventing overgrowth of contaminating bacteria are critical issues relevant to the commercialization of the mixotrophic microalgae cultivation process. In this paper, we report the use of magnesium aminoclay (MgAC) nanoparticles for enhanced lipid production from oleaginous Chlorella sp. KR-1 with simultaneous control of KR-1-associated bacterial growth in mixotrophic cultures with glucose as the model substrate. Addition of 0.01–0.1 g/L MgAC promoted microalgal biomass production better than the MgAC-less control, via differential biocidal effects on microalgal and bacterial cells (the latter being more sensitive to MgAC's bio-toxicity than the former). The inhibition effect of MgAC on co-existing bacteria was, as based on density-gradient-gel-electrophoresis (DGGE) analysis, largely dosage-dependent and species-specific. MgAC also, by inducing an oxidative stress environment, increased both the cell size and lipid content of KR-1, resulting in a considerable, ∼25% improvement of mixotrophic algal lipid productivity (to ∼410 mg FAME/L/d) compared with the untreated control.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry, Chungnam National University, Korea Institute of Energy Research, Gachon University
Contributors: Kim, B., Praveenkumar, R., Lee, J., Nam, B., Kim, D. M., Lee, K., Lee, Y. C., Oh, Y. K.
Number of pages: 6
Pages: 608-613
Publication date: 1 Nov 2016
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 219
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2016): CiteScore 9.9 SJR 2.215 SNIP 1.945
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Aminoclay, Bacteria, Chlorella, Lipid, Mixotrophic culture
Source: Scopus
Source ID: 84982219447

Research output: Contribution to journalArticleScientificpeer-review

Mild pressure induces rapid accumulation of neutral lipid (triacylglycerol) in Chlorella spp.

Effective enhancement of neutral lipid (especially triacylglycerol, TAG) content in microalgae is an important issue for commercialization of microalgal biorefineries. Pressure is a key physical factor affecting the morphological, physiological, and biochemical behaviors of organisms. In this paper, we report a new stress-based method for induction of TAG accumulation in microalgae (specifically, Chlorella sp. KR-1 and Ch. sp. AG20150) by very-short-duration application of mild pressure. Pressure treatments of 10–15 bar for 2 h resulted in a considerable, ∼55% improvement of the 10–100 g/L cells’ TAG contents compared with the untreated control. The post-pressure-treatment increase of cytoplasmic TAG granules was further confirmed by transmission electron microscopy (TEM). Notwithstanding the increased TAG content, the total lipid content was not changed by pressurization, implying that pressure stress possibly induces rapid remodeling/transformation of algal lipids rather than de novo biosynthesis of TAG.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Chemistry and Bioengineering, Research group: Industrial Bioengineering and Applied Organic Chemistry, Chungnam National University, Korea Institute of Energy Research
Contributors: Ramasamy, P., Kim, B., Lee, J., Vijayan, D., Lee, K., Nam, B., Jeon, S. G., Kim, D. M., Oh, Y. K.
Number of pages: 5
Pages: 661-665
Publication date: 1 Nov 2016
Peer-reviewed: Yes

Publication information

Journal: Bioresource Technology
Volume: 220
ISSN (Print): 0960-8524
Ratings: 
  • Scopus rating (2016): CiteScore 9.9 SJR 2.215 SNIP 1.945
Original language: English
ASJC Scopus subject areas: Bioengineering, Environmental Engineering, Waste Management and Disposal
Keywords: Induction, Microalgae, Neutral lipid, Pressure stress, Triacylglycerol
DOIs: