Sökning: "hydrogen"

Visar resultat 6 - 10 av 1542 avhandlingar innehållade ordet hydrogen.

1. 6. Atomistic Modelling of Materials for Clean Energy Applications : hydrogen generation, hydrogen storage, and Li-ion battery

   Författare :Zhao Qian; Rajeev Ahuja; Börje Johansson; Antonio Ferreira da Silva; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Renewable energy; Materials science; Hydrogen production; Hydrogen storage; Li-ion battery; Density functional theory; SRA - Energy; SRA - Energi; SRA - E-Science SeRC ; SRA - E-vetenskap SeRC ;

   Sammanfattning : In this thesis, a number of clean-energy materials for hydrogen generation, hydrogen storage, and Li-ion battery energy storage applications have been investigated through state-of-the-art density functional theory.As an alternative fuel, hydrogen has been regarded as one of the promising clean energies with the advantage of abundance (generated through water splitting) and pollution-free emission if used in fuel cell systems. LÄS MER

3. 7. The interaction of hydrogen with metallic glass

   Författare :Johan Bylin; Gunnar K. Pálsson; Ralph H. Scheicher; Gabriella Andersson; Astrid Pundt; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; metallic glass; hydrogen; thin film; density functional theory; stochastic quenching; molecular dynamics; x-ray diffraction; pair distribution function; neutron reflectometry; volume expansion; elastic hydrogen-hydrogen interaction; dipole force tensor; electronic structure; optical conductivity; resistivity; optical transmission; x-ray photoelectron spectroscopy; thermodynamic driving force; Gibbs free energy; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

   Sammanfattning : Combining theoretical ab initio calculations with high-purity thin film sample synthesis and in situ measurements is a compelling way to bridge the gap in our understanding concerning hydrogen in metallic glasses, which is the primary work of this dissertation thesis. The main emphasis has been on how hydrogen affects the structure of metallic glasses, and how those changes influence not only the electronic properties of the amorphous metals but also their thermal stability. LÄS MER

4. 8. Caldicellulosiruptor Saccharolyticus: an Ideal Hydrogen Producer?

   Författare :Sudhanshu Pawar; Avdelningen för kemiteknik; []
   Nyckelord :Caldicellulosiruptor owensensis; Caldicellulosiruptor saccharolyticus; hydrogen; volumetric hydrogen productivity; biofilm; osmotolerance; wheat straw hydrolysate; evolutionary engineering; CSTR; UA reactor and uracil auxotrophy;

   Sammanfattning : Caldicellulosiruptor saccharolyticus is an extremely thermophilic, strictly anaerobic, Gram-positive and cellulolytic microorganism with a natural ability to produce hydrogen (H2) at nearly theoretical maximum yield, i.e. 4 mol/ mol of glucose. LÄS MER

5. 9. Risk analysis of hydrogen as a vehicular fuel

   Författare :Helen Bigün; KTH; []
   Nyckelord :Hydrogen; Liquid hydrogen; Safety analysis; Risk analysis; Fault tree; Event tree; Failure modes; Electric vehicle; Fuel cell; Driving H2 fuelled vehicle; Alternative fuel;

   Sammanfattning : .... LÄS MER

7. 10. Hydrogen in nano-sized metals : Diffusion and hysteresis effects

   Författare :Wen Huang; Björgvin Hjörvarsson; Max Wolff; Gavin Walker; Uppsala universitet; []
   Nyckelord :Hydrogen; diffusion; hysteresis; optical technique; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

   Sammanfattning : Metal hydrides can be used as hydrogen storage materials for fuel cells and batteries, and as sensors for detecting hydrogen gas. The use of metal hydrides for hydrogen storage can be hindered by poor kinetics and low capacity. Moreover, poor sensitivity, long recovery and response time, limit the applications of metal hydrides as hydrogen sensors. LÄS MER