Sökning: "XANES"

Visar resultat 21 - 25 av 41 avhandlingar innehållade ordet XANES.

  1. 21. Spectroscopic characterization of lignocellulosic biomass

    Författare :Mikael Thyrel; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : This thesis focuses on characterization of organic components and inorganic elements in lignocellulosic biomass. The chosen biomass models were mostly wood from conifers and straw from rhizomatous grasses but also forest-based residues and agro-based plants. LÄS MER

  3. 22. Phosphorus chemistry in managed forest soils : effects of weathering and wood ash fertilisation

    Författare :Marius Tuyishime; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Weathering and Podzolisation are key mechanisms that transform primary mineral apatite into a phosphorus (P) pool with low solubility. In addition, intensive forest harvesting removes nutrients from the soil, reducing P availability. LÄS MER

  4. 23. Sulfur cycling in Swedish arable soils : a chemical perspective

    Författare :Kristin Boye; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : Sulfur (S) is an essential plant nutrient. Decreased S deposition in combination with a switch to high-analysis N/P-fertilizers has increased the need for S fertilization. Thus, soil research directed at understanding soil sulfur properties and processes has intensified. LÄS MER

  5. 24. The adsorption of arsenic oxyacids to iron oxyhydroxide columns : including studies of weakly hydrated ions and molecules in aqueous solution

    Författare :Johan Mähler; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : The fundamental side of this project includes determination of ionic radii and plausible hydration numbers for the weakly hydrated alkali metal ions in solution, as well as an investigation of the intramolecular bond lengths of arsenic oxyacid species and orthotelluric acid. Experimental methods such as EXAFS, XANES and LAXS have been used for these purposes, as well as thorough screening for relevant structures in crystal structure databases. LÄS MER

  7. 25. Chemical Speciation of Sulfur and Metals in Biogas Reactors : Implications for Cobalt and Nickel Bio-uptake Processes

    Författare :Sepehr Shakeri Yekta; Bo Svensson; Ulf Skyllberg; Åsa Danielsson; Charles Banks; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Biogas; Anaerobic digestion; Chemical speciation; bio-uptake; Sulfur; Iron; Cobalt; Nickel; Biogas; Anaerob nedbrytning; Kemisk speciering; Bio-upptag; Svavel; Järn; Kobolt; Nickel;

    Sammanfattning : A balanced supply of micronutrients, including metals such as iron (Fe), cobalt (Co), and nickel (Ni), is required for the efficient and stable production of biogas. During biogas formation, the uptake of micronutrient metals by microorganisms is controlled by a complex network of biological and chemical reactions, in which reduced sulfur (S) compounds play a central role. LÄS MER