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Showing result 1 - 5 of 39 swedish dissertations matching the above criteria.

  1. 1. Theoretical perspectives on ultrafast and non-linear spectroscopy

    Author : Emil Vinas Boström; Matematisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Non-linear optics; Ultrafast dynamics; Non-equilibrium Green s functions; Density functional theory; Multi-photon absorption; Second harmonic generation; Desorption dynamics; Auger decay; Charge-separation dynamics; Quantum Zeno effect; Fysicumarkivet A:2018:Vinas Boström;

    Abstract : In this thesis we discuss a theoretical description of ultrafast and non-linear spectroscopy. Due to the high intensities and ultrashort pulse durations involved in such experiments, it is necessary to use an explicitly time-dependent formalism. READ MORE

  2. 2. Model Studies of Electron Transfer and Reaction Dynamics at Surfaces

    Author : Johan Strömquist; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; dissociation; desorption; oxidation; hot precursors; surface chemical reaction; chemiluminescence; surface harpooning; charge transfer; electron emission; transient mobility; non-adiabaticity;

    Abstract : Charge-transfer is of key importance in many physical, chemical and biological processes, including surface reactions. This thesis consists of several theories for and model studies of surface reactions that are initiated by electron transfer between the surface to a molecule. READ MORE

  3. 3. Studies on the barrier properties of exterior wood coatings

    Author : Jan Ekstedt; KTH; []
    Keywords : Coatings; surfactants; water absorption value; EN 927; paint; additives; moisture dynamics; absorption; desorption; artificial weathering; artificial exposure; computerized tomography; MRI.;

    Abstract : Coatings for exterior wood have two basic functions. One isto give an aesthetically acceptable surface appearance andcolour. The other is to provide protection against wooddegradation by microbiological or physical attack. READ MORE

  4. 4. On Modeling the Dynamics of Fixed Biofilm Reactors. With focus on nitrifying trickling filters

    Author : Torsten Wik; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; operation; transfer functions; biofilm reactors; adsorption; dormancy; modeling; dynamics; nitrification;

    Abstract : Fixed biofilms, which are matrix-enclosed populations of organisms attached to solid surfaces, are increasingly used in environmental biotechnology processes, such as the treatment of potable water and wastewater. This thesis aims to give some insight into the dynamic modeling of biofilms and fixed biofilm reactors, with a focus on nitrifying trickling filters (NTFs) for the treatment of wastewater. READ MORE

  5. 5. Structure-dynamics relationships in perovskite oxyhydrides and alkali silanides

    Author : Carin Eklöf-Österberg; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; hydrogen storage material; long range diffusion; oxyhydride; neutron scattering; localized motion; hydride ion conduction; hydrogen dynamics;

    Abstract : This thesis focuses on investigations of the local structure and dynamics of two classes of hydrogen-containing, energy relevant, materials; perovskite type oxyhydrides BaTiO3-xHx and alkali silanides ASiH3 (A = K and Rb). In the area of oxyhydrides, which are of relevance for the development of electrolytes in fuel cells and batteries, the aim is to elucidate the dynamics and electronic character of the hydrogen species in the materials. READ MORE