Sökning: "cell modelling"

Visar resultat 21 - 25 av 293 avhandlingar innehållade orden cell modelling.

  1. 21. Electrochemical characterisation of porous cathodes in the polymer electrolyte fuel cell

    Författare :Frédéric Jaouen; KTH; []
    Nyckelord :polymer electrolyte fuel cell; cathode; mass transport; porous electrode; modelling; agglomerate model; electrochemical impedance spectroscopy; current interrupt; transient techniques; non-noble catalysts;

    Sammanfattning : Polymer electrolyte fuel cells (PEFC) convert chemicalenergy into electrical energy with higher efficiency thaninternal combustion engines. They are particularly suited fortransportation applications or portable devices owing to theirhigh power density and low operating temperature. LÄS MER

  3. 22. Transverse anisotropy in softwoods : Modelling and experiments

    Författare :Carl S. Modén; Lars Berglund; Lennart Salmén; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Softwood; Cellular solid; Anisotropy; Deformation mechanisms; Materials science; Teknisk materialvetenskap;

    Sammanfattning : Transverse anisotropy is an important phenomenon of practical and scientific interest. Although the presence of ray tissue explains the high radial modulus in many hardwoods, experimental data in the literature shows that this is not the case for pine. LÄS MER

  4. 23. Modelling and Experimental Investigation of the Dynamics in Polymer Electrolyte Fuel Cells

    Författare :Katarina Wiezell; Göran Lindbergh; Lars Pettersson; Anders Dahlkild; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; polymer electrolyte fuel cell; modelling; electrochemical impedance spectroscopy; water transport; membrane; Electrochemistry; Elektrokemi;

    Sammanfattning : In polymer electrolyte fuel cells (PEFC) chemical energy, in for example hydrogen, is converted by an electrochemical process into electrical energy. The PEFC has a working temperature generally below 100 °C. Under these conditions water management and transport of oxygen to the cathode are the parameters limiting the performance of the PEFC. LÄS MER

  5. 24. Towards forecasting epigenetic repression

    Författare :Moa J. Lundkvist; Yuri B. Schwartz; Ludvig Lizana; Peter V. Kharchenko; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; epigenetics; Polycomb; PRC1; PRC2; H3K27 methylation; Monte-Carlo simulation; chromatin structure; Drosophila; molekylär bioteknik inst f molekylärbiologi ; molecular biotechnology dept of molecular biology ;

    Sammanfattning : Multicellular organisms form many different cell types from one genome, which requires differential gene activity. The Polycomb system upholds the correct gene expression programs by epigenetically silencing genes that encode critical transcription regulators. LÄS MER

  7. 25. Dynamic Solid Oxide Fuel Cell Modelling for Non-steady State Simulation of System Applications

    Författare :Miriam Kemm; Kraftverksteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; termodynamik; applied thermodynamics; Termisk teknik; Transient analysis; Technological sciences; Teknik; Energy research; Energiforskning; Thermal engineering; Thermal stress; Solid Oxide Fuel Cell; Fuel cell modelling;

    Sammanfattning : Most of the world's energy generation is based on fossil fuels such as coal and oil, which already today but even more in the future, will cause various problems. One issue is their limited availability, which stands in conflict to the increasing global energy consumption. LÄS MER