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Visar resultat 1 - 5 av 73 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Surface structure and catalytic activity of Pd and Fe oxide surfaces and thin films

    Författare :Mikhail Shipilin; Synkrotronljusfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Surface X-ray diffraction SXRD ; Heterogeneous catalysis; Pd; PdO; Fe; FeO; Thin films; Fysicumarkivet A:2016:Shipilin;

    Sammanfattning : The present work is devoted to atomic scale structural studies of the surfaces of model heterogeneous catalysts relevant to oxidation reactions. A novel approach using high-energy surface X-ray diffraction combined with mass-spectrometry measurements is employed to perform in situ structural characterization of Pd(100) and Pd(553) single crystal surfaces acting as catalysts in the process of CO oxidation under semirealistic conditions. LÄS MER

  3. 2. Growth of high quality Fe thin films : A study of the effect of mismatch strain on the physical properties of Fe

    Författare :Anna Lena Ravensburg; Vassilios Kapaklis; Björgvin Hjörvarsson; Tomas Kubart; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; thin film growth; crystal quality; strain; magnetism; electronic transport; Fysik; Physics;

    Sammanfattning : The work in this licentiate is devoted to investigating the epitaxial growth of thin Fe layers on MgAl2O4 (001) and MgO (001) substrates using dc magnetron sputtering. The aim is to qualitatively and quantitatively determine the crystal quality of the grown Fe layers depending on their thickness, substrate material, and selected deposition parameters. LÄS MER

  4. 3. Magnetism and Structure of Thin 3d Transition Metal Films : XMCD and EXAFS using Polarized Soft X-Rays

    Författare :Anders Hahlin; Dimitri Arvanitis; Olof Karis; Claus Schneider; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; thin film; xmcd; exafs; anisotropy; coherence; circular polarization; magnetism; Fe; Co; Ag; Fysik; Physics; Fysik; Fysik; Physics;

    Sammanfattning : In this Thesis the magnetic and structural properties of thin epitaxial Fe, Co, and Ni films are discussed. Some of the in-situ prepared samples were used to characterize the degree of circular polarization of the newly installed beamline D1011 at MAX-lab. LÄS MER

  5. 4. Exploring the Magnetism of Ultra Thin 3d Transition Metal Films

    Författare :Cecilia Andersson; Olof Karis; Dimitri Arvanitis; Chi-Chang Kao; Uppsala universitet; []
    Nyckelord :Physics; thin film; xmcd; xrms; exafs; anisotropy; magnetism; Fe; Ni; Co; Ag; Cu; Fysik;

    Sammanfattning : In this thesis the magnetic and structural properties of ultra-thin 3d transition metals films have been investigated, in particular Fe, Ni and Co films. X-ray Magnetic Circular Dichroism (XMCD) has provided element specific spin (ms ) and orbital (ml ) moments per atom by utilizing the magneto optic sum-rules. LÄS MER

  7. 5. Cantor-Alloy-Based Multicomponent Nitride Thin Films

    Författare :Smita Gangaprasad Rao; Per Eklund; Arnaud Le Febvrier; Yutao Pei; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Thin films; Multicomponent alloys; Magnetron sputtering;

    Sammanfattning : In this Thesis, I have investigated multicomponent alloy based thin films synthesized by magnetron sputtering. The studies in the thesis are centered around the phase diagram of the CrFeCoNi nitrogen containing system. LÄS MER