Sökning: "vanadium oxides"

Visar resultat 1 - 5 av 24 avhandlingar innehållade orden vanadium oxides.

  1. 1. Resonant Soft X-Ray Emission Spectroscopy of Vanadium Oxides and Related Compounds

    Författare :Thorsten Schmitt; Joseph Nordgren; Laurent Duda; Stefan Eisebitt; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; vanadium oxides; Li-battery; cathode materials; copper oxides; soft X-ray absorption; soft X-ray emission; resonant inelastic X-ray scattering; cluster model calculations; Fysik; Physics; Fysik;

    Sammanfattning : This thesis addresses the electronic structure of vanadium and copper oxides using soft X-ray absorption (SXA) spectroscopy and resonant inelastic X-ray scattering (RIXS) at high brightness synchrotron radiation sources. In RIXS incident photons, tuned to the energy of specific absorption resonances, are inelastically scattered leaving behind a low energy valence excitation in the system studied. LÄS MER

  2. 2. Aqueous Exfoliation of Transition Metal Oxides for Energy Storage and Photocatalysis Applications : Vanadium Oxide and Molybdenum Oxide Nanosheets

    Författare :Ahmed S. Etman; Junliang Sun; Yury Gogotsi; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; aqueous exfoliation; vanadium oxide nanosheets; molybdenum oxide nanosheets; energy storage; photocatalysis; Inorganic Chemistry; oorganisk kemi;

    Sammanfattning : Two-dimensional (2D) transition metal oxides (TMOs) are a category of materials which have unique physical and chemical properties compared to their bulk counterparts. However, the synthesis of 2D TMOs commonly includes the use of environmental threats such as organic solvents. LÄS MER

  3. 3. Dissolved and suspended transport of tungsten, molybdenum, and vanadium in natural waters

    Författare :Susanne Bauer; Johan Ingri; Carl-Magnus Mörth; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; tungsten; molybdenum; vanadium; Baltic Sea; redox cycling; suspended particles; boreal rivers; Applied Geology; Tillämpad geologi;

    Sammanfattning : Some transition metals and metalloids occur primarily as oxyanions in natural waters including antimony, arsenic, chromium, molybdenum, tungsten and vanadium. These oxyanions can pass through cell walls along the same pathways as phosphate or sulfate. Some of these oxyanions are essential for life, but in high concentrations they become all toxic. LÄS MER

  4. 4. Selective oxidation over mixed oxide catalysts

    Författare :Robert Häggblad; Avdelningen för kemiteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; propane; catalysis; Selective oxidation; transition metal oxides; vanadium; molybdenum; methanol oxidation; ammoxidation; propene; acrylonitrile; formaldehyde;

    Sammanfattning : Since the metal oxide catalysts used in many chemical processes show very high selectivity for the products aimed at, both today and in the future, they play a key role in the environmentally and economically sustainable production of chemical intermediates. Two processes of this sort have been studied in the thesis: the ammoxidation of propane and propene over a Mo-V-Nb-Te-oxide catalyst and the selective oxidation of methanol over vanadium-based catalysts. LÄS MER

  5. 5. Measurements of the thermodynamic activities of chromium  and vanadium oxides in CaO-MgO-Al2O3-SiO2 slags

    Författare :Pengli Dong; Seshadri Seetharaman; Mselly Mbwambo Nzotta; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; thermodynamic activity; chromium oxide; vanadium oxide; equilibrium; slags; slag basicity; gas-equilibration technique; Metallurgical process engineering; Metallurgisk processteknik;

    Sammanfattning : In the present work, the thermodynamic activities of chromium and vanadium oxide in CaO-SiO2-MgO-Al2O3 slags were measured using gas-slag equilibration technique. The slag was equilibrated with a gas mixture of CO, CO2 and Ar gases enabling well-defined oxygen partial pressures in the gas mixture (PO2=10-3,10-4,10-5 Pa) at temperatures 1803, 1823K, 1873, 1923 K. LÄS MER