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Visar resultat 11 - 15 av 79 avhandlingar som matchar ovanstående sökkriterier.

1. 11. X-ray Spectroscopic Studies of Materials for Nuclear Technology

   Författare :Johan Vegelius; Sergei Butorin; Frank de Groot; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; XAS; XES; RIXS; amorphous; DOS; spectroscopy; actinides; copper; uranium; plutonium;

   Sammanfattning : X-ray spectroscopic experiments, including X-ray absorption spectroscopy (XAS), X-ray emission spectroscopy (XES) and resonant inelastic X-ray scattering (RIXS), were performed in a large energy range (60-9000 eV) on a variety of systems, probing different elements and orbitals. The systems can preferably be divided into three groups: Actinides, copper systems and amorphous materials. LÄS MER

3. 12. Synchrotron light based spectroscopy of MBE-grown (GaMn)As structures

   Författare :Johan Adell; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Diluted magnetic Semiconductor; GaMn As; UPS; XAS; XPS; RPES;

   Sammanfattning : Structures based on the diluted magnetic semiconductor (GaMn)As have been grown by low temperature molecular beam epitaxy and studied using synchrotron radiation based electron spectroscopy. An investigation of modifications due to in situ low temperature annealing under amorphous As capping has been performed. LÄS MER

4. 13. Synchrotron Radiation Studies of Free and Adsorbed Molecules

   Författare :Zhuo Bao; Maria Novella Piancastelli; Svante Svensson; Denis Ceolin; Edwin Kukk; Uppsala universitet; []
   Nyckelord :Physics; Synchrotron radiation; Auger electron spectroscopy; one-step model; Post Collision Interaction PCI ; theoretical modeling; molecules; adsorbates; UPS; XPS; XAS; NEXAFS; Fysik;

   Sammanfattning : This thesis contains two parts. The first part concerns the research work on free molecules using synchrotron-radiation-related techniques. Auger electron spectra of two free open-shell molecules, O2 and NO, were studied experimentally and theoretically. LÄS MER

5. 14. Interaction of CO and methane with platinum, Low-temperature oxidation and sensor response mechanisms

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

   Sammanfattning : The aim of this thesis project was to increase the understanding of the mechanisms for low-temperature oxidation of carbon monoxide and methane over supported platinum catalysts. In situ spectroscopic methods together with mass spectrometry were used to study the catalysts during both steady state and transient conditions. LÄS MER

7. 15. Mesoporous Titania for High Rate Electrochemical Energy Storage

   Författare :Giulio Calcagno; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mesoporous Titanium Dioxide; XAS; Pseudocapacitance; Hybrid Asymmetric Supercapacitors;

   Sammanfattning : Mesoporous titanium oxides are increasingly attracting interest as potential candidates for fast electrochemical energy storage. In this thesis, mesoporous titania of different polymorphs have been evaluated in relation to their ability to reversibly store Li+ ions inside their structure. LÄS MER