Search for dissertations about: "XAS"

Showing result 6 - 10 of 79 swedish dissertations containing the word XAS.

  2. 6. Interactions of methane and carbon monoxide with platinum - Supported catalysts and chemical sensors

    Author : Elin Becker; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Periodic operation In situ spectroscopy; XAS; CO; Sensing mechanism; Low-temperature activity; XANES; Pt; Environmental catalysis; Support material; CH4; Chemical sensors;

    Abstract : This thesis aims at increasing the understanding of the interactions of methane and carbon monoxide with platinum in connection to catalysis and sensor technology for emission control. Specifically, the low-temperature oxidation of methane and carbon monoxide over supported platinum catalysts and the sensor response mechanism towards CO of platinum-based chemical field effect sensors were studied. READ MORE

  4. 7. In situ X-Ray Spectroscopy of Ethylene Epoxidation over Ag and studies of Li-ion batteries and Cu sulfidation

    Author : Paw Kristiansen; Laurent Duda; Thorsten Schmitt; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; In situ; XAS; RIXS; heterogeneous catalysis; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Abstract : This thesis is based on experiments applying synchrotron based X-ray Absorption Spectroscopy(XAS) and Resonant Inelastic X-ray Scattering (RIXS) in the soft X-ray region to energy related systems. The main work of this thesis has been to develop a reaction cell that allowed for in situ XAS and RIXS investigations of the partial epoxidation of ethylene over a Ag catalyst at 1 atm and up to 250C. READ MORE

  5. 8. Electronic and Geometric Structure of Phthalocyanines on Metals

    Author : Masumeh-Nina Shariati; Maria Novella Piancastelli; Carla Puglia; Kajsa Uvdal; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; monolayer; multilayer; metal-free phthalocyanine; metal phthalocyanine; interaction; intermolecular; adsorbate-substrate; XPS; XAS; STM; DFT; alkali; metallization;

    Abstract : Adsorption of monolayers and multilayers of metal-free and metal phthalocyanines molecules on metal surfaces has been investigated using complementary microscopic and synchrotron-based spectroscopic techniques. It was observed by STM measurements that at monolayer coverage the adsorption direction of the metal-free phthalocyanine molecules with respect to the gold surface vary as a function of temperature, i. READ MORE

  6. 9. Interactions between Fe and organic matter and their impact on As(V) and P(V)

    Author : Anneli Sundman; Per Persson; Thomas Borch; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; XAS; Fe III ; As V ; P V ; natural organic matter; Fe II; III -NOM complexes; Krycklan catchment; Earth Sciences with Specialization Environmental Analysis; geovetenskap med inriktning mot miljöanalys;

    Abstract : Iron (Fe) speciation is important for many biogeochemical processes. The high abundance and limited solubility of Fe(III) are responsible for the widespread occurrence of Fe(III) minerals in the environment. READ MORE

  7. 10. Fate of riverine iron over estuarine salinity gradients

    Author : Simon Herzog; Enhet akvatisk ekologi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; iron Fe ; Organic matter; boreal rivers; XAS; DLS; Fe isotope;

    Abstract : Rivers have traditionally not been considered important sources of bioavailable iron (Fe) to the marine waters, since most Fe is lost by salinity-induced aggregation and sedimentation during estuarine mixing. However, recent studies from boreal rivers found a remarkably high Fe stability, probably due to the interaction with organic matter. READ MORE