Search for dissertations about: "ELECTRON-DENSITY"

Showing result 11 - 15 of 104 swedish dissertations containing the word ELECTRON-DENSITY.

  2. 11. From Time-Averaged to Time-Resolved Crystallography: Studies on Superoxide Dismutase and Myoglobin

    Author : Thomas Ursby; Lunds universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; superoxide dismutase; Bayesian statistics; electron difference maps; synchrotron; docking site; photolysis; myoglobin; Time-resolved crystallography; Laue; thermostability; Sulfolobus solfataricus; Molecular biophysics; Molekylär biofysik;

    Abstract : We have studied protein motions with nanosecond time-resolved crystallography. The release of carbon monoxide from its complex with myoglobin (MbCO) was triggered by nanosecond laser pulses. X-ray data were collected with time delays ranging from 4 ns to 1.9 ms using the Laue method, at the European Synchrotron Radiation Facility in Grenoble. READ MORE

  4. 12. 3D nano-tomography using coherent X-rays

    Author : Maik Kahnt; Lunds universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ptychography; Tomography; Phase reconstruction; X-ray microscopy;

    Abstract : X-rays allow to non-destructively investigate biological, chemical or physical processes at the nano-scale. Their high penetration depth in matter allows to investigate samples even inside sample environments, which would be difficult with complementary methods such as transmission electron microscopy (TEM). READ MORE

  5. 13. Models of Auger Neutralization and Tunneling at Metal Surfaces

    Author : Tony Fondén; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : This thesis consists of a theoretical study of electron transfer at metal surfaces. It considers two types of electron transfer (electron tunneling and Auger neutralization) that both can be used as a spectroscopy to investigate the surface electronic structure. READ MORE

  6. 14. Theoretical and computational advances in small-angle x-ray scattering tensor tomography

    Author : Leonard Nielsen; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; tensor tomography; reciprocal space map; small-angle scattering;

    Abstract : The relationships between microscopic and macroscopic structures is a central topic of materials physics. Small-angle x-ray scattering (SAXS) is a powerful experimental technique for probing and mapping variations in electron density, given by the reciprocal space map, down to the nanometer scale in two dimensions. READ MORE

  7. 15. Characterization and Analysis of Surface Passivations and Gate Insulators for AlGaN/GaN Microwave HFETs

    Author : Martin Fagerlind; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HFET; passivation characterization; passivation; AlGaN GaN heterostructure;

    Abstract : The large bandgap of gallium nitride (GaN) and aluminum gallium nitride (AlGaN) offers an inherently high intrinsic breakdown field. When the materials are joined into the AlGaN/GaN heterostructure a 2-dimensional electron gas (2DEG) with a high electron density as well as high electron mobility is generated. READ MORE