Sökning: "x-ray emission spectroscopy"

Visar resultat 6 - 10 av 104 avhandlingar innehållade orden x-ray emission spectroscopy.

1. 6. Non-linear Spectroscopy of Conical Intersections with XUV and X-ray Photons

   Författare :Deependra Jadoun; Markus Kowalewski; Faris Gelmukhanov; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Conical Intersections; Non-linear Spectroscopy; Quantum Dynamics; Perturbation Theory; Ultrafast Spectroscopy; X-ray; XUV; Theoretical Physics; teoretisk fysik;

   Sammanfattning : Conical intersections (CIs) appear in a molecule due to the breakdown of the Born-Oppenheimer approximation when the energy difference between two or more electronic states decreases. CIs are known to play a crucial role in processes such as photosynthesis and vision in the human eye, and therefore it is important to probe the existence of such entities in molecules. LÄS MER

3. 7. Characterisation and application of a laser-based hard x-ray source

   Författare :Matthias Grätz; Atomfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; X-ray spectroscopy; radiography; medical imaging; differential imaging; time-gated imaging; scatter reduction; Monte Carlo simulation; Atomic and molecular physics; computed tomography; Fysicumarkivet A:1998:Grätz; laser-produced plasma; Atom- och molekylärfysik; X-ray sources;

   Sammanfattning : Hard X-rays are generated by focusing 110 fs laser pulses with intensities of about 1017 W·cm-2 onto solid metal targets. Characteristic properties of this X-ray source are the small source size, the short pulse duration and the high peak flux. LÄS MER

4. 8. Passivity & Breakdown of Super Duplex Stainless Steel : Studied with Electrochemical & Synchrotron Techniques

   Författare :Marie Långberg; Jinshan Pan; David Lindell; Ulf Kivisäkk; Edvin Lundgren; Sannakaisa Virtanen; KTH; []
   Nyckelord :Passive film; duplex stainless steel; synchrotron X-ray reflectivity; X-ray diffraction; X-ray fluorescence; hard X-ray Photoelectron emission microscopy; X-ray Photoelectron spectroscopy; Electrochemical impedance; Kemi; Chemistry;

   Sammanfattning : Super duplex stainless steel consists of two phases: austenite and ferrite, and is a highly corrosion resistant material, with a wide range of applications. The corrosion resistance of stainless steels is determined by the performance of a spontaneously formed thin Cr oxide rich film with a thickness of 1-3 nm. LÄS MER

5. 9. Soft X-ray Emission Spectroscopy of Liquids and Lithium Battery Materials

   Författare :Andreas Augustsson; Joseph Nordgren; Jinghua Guo; Kevin Smith; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Atomic and molecular physics; Soft X-ray emission; resonant inelastic X-ray scattering; lithium battery; electronic structure; liquid water; Atom- och molekylfysik; Atomic and molecular physics; Atom- och molekylfysik;

   Sammanfattning : Lithium ion insertion into electrode materials is commonly used in rechargeable battery technology. The insertion implies changes in both the crystal structure and the electronic structure of the electrode material. LÄS MER

7. 10. Anion redox processes in novel battery cathode materials investigated by soft X-ray spectroscopy

   Författare :Felix Massel; Laurent Duda; Håkan Rensmo; Maria Hahlin; Kevin Smith; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; soft X-ray spectroscopy; X-ray absorption spectroscopy XAS ; resonant inelastic X-ray scattering RIXS ; lithium-ion battery LIB ; sodium-ion battery SIB ; anionic redox; cathode materials; layered manganese oxide; spinel LNMO;

   Sammanfattning : This thesis presents experimental investigations of the electronic structure of emerging and novel cathode materials used in lithium- and sodium-ion batteries. The investigated materials include a range of oxide materials containing the elements nickel and manganese. LÄS MER