Sökning: "HYDROGEN ANALYSIS"

Visar resultat 21 - 25 av 333 avhandlingar innehållade orden HYDROGEN ANALYSIS.

  1. 21. Hydrogen Production by Caldicellulosiruptor species: The Organism and the Metabolism

    Författare :Ahmad Zeidan; Teknisk mikrobiologi; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Extreme thermophile; Caldicellulosiruptor; Biohydrogen; Co-culture; Coexistence; Hydrogen tolerance; Genome-scale reconstruction; In silico; Flux balance analysis;

    Sammanfattning : Hydrogen holds a great promise as an efficient and clean future energy carrier due to its high energy density and lack of pollutant generation. Anaerobic degradation of organic substrates by heterotrophic microorganisms enables the production of hydrogen from a wide spectrum of agricultural feedstock and waste products. LÄS MER

  3. 22. Effect of boron and hydrogen on microstructure and mechanical properties of cast Ti-6Al-4V

    Författare :Raghuveer Gaddam; Magnus Hörnqvist; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Titanium alloy; Metallography; Fractography; Castings; Low cycle fatigue; Hydrogen; Boron; Materialteknik; Engineering Materials;

    Sammanfattning : Titanium and its alloys are widely used in applications ranging from aeroengines and offshore equipment to biomedical implants and sporting goods, owing to their high ratio of strength to density, excellent corrosion resistance, and biomedical compatibility. Among the titanium alloys used in aerospace, Ti-6Al-4V (an α+β alloy) is the most widely used, in applications in which the temperature may reach 350°C, at which point it retains good fatigue and fracture properties as well as moderate tensile strength and ductility. LÄS MER

  4. 23. Analysis of Deformation of Gas Diffusion Layers and the Impact on Performance of PEM Fuel Cells

    Författare :Jiatang Wang; Värmeöverföring; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; PEM fuel cell; compression ratio; assembly pressure; porosity; deformed GDL; electric resistance; transport phenomena; model; performance; analysis; OpenFOAM;

    Sammanfattning : Proton exchange membrane (PEM) fuel cells have been promoted due to significant breakthroughs in various aspects and increasing public interests. The porous features of the gas diffusion layer (GDL) and the necessary assembly processes generate localized pressure forces on the channel/shoulder structure of the bi-polar plates (BPP). LÄS MER

  5. 24. Proton-Coupled Electron Transfer from Hydrogen-Bonded Phenols

    Författare :Tania Irebo; Leif Hammarström; James M. Mayer; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Proton-coupled electron transfer; phenol oxidation; hydrogen bonds; artificial photosynthesis; promoting vibrations; proton transfer; laser flash-quench; transient absorption.; Physical chemistry; Fysikalisk kemi; Fysikalisk kemi; Physical Chemistry;

    Sammanfattning : Proton-coupled electron transfer (PCET) is one of the elementary reactions occurring in many chemical and biological systems, such as photosystem II where the oxidation of tyrosine (TyrZ) is coupled to deprotonation of the phenolic proton. This reaction is here modelled by the oxidation of a phenol covalently linked to a Ru(bpy)32+-moitey, which is photo-oxidized by a laser flash-quench method. LÄS MER

  7. 25. Dissolving pulp : Multivariate Characterisation and Analysis of Reactivity and Spectroscopic Properties

    Författare :Kristina Elg Christoffersson; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemistry; Dissolving pulp; reactivity; solid state 13C NMR spectroscopy; NIR spectroscopy; multivariate analysis; cellulose; viscose; Kemi; Chemistry; Kemi;

    Sammanfattning : Various chemical properties can be used to characterise dissolving pulp. The quality of the pulp must be carefully controlled to ensure that it meets the requirements for its intended use and the further processes to be applied. LÄS MER