Sökning: "spectroscopy"

Visar resultat 16 - 20 av 2809 avhandlingar innehållade ordet spectroscopy.

  1. 16. Photoelectron Spectroscopy on Atoms, Molecules and Clusters : The Geometric and Electronic Structure Studied by Synchrotron Radiation and Lasers

    Författare :Torbjörn Rander; Olle Björneholm; Gunnar Öhrwall; Maxim Tchaplyguine; Matthias Neeb; Uppsala universitet; []
    Nyckelord :Atomic and molecular physics; Free clusters; Electron spectroscopy; Doped clusters; Laser excitation; Alkali metals; Electronic structure; Geometric structure; X-ray photoelectron spectroscopy XPS ; Resonant Auger spectroscopy RAS ; Near-threshold x-ray absorption fine structure NEXAFS ; Ultraviolet photoelectron spectroscopy UPS ; Detuning; Ultra-fast dissociation UFD ; Sodium; Potassium; Oxygen; Bromomethane; Argon; Xenon; Krypton; Molecular field splitting; Core hole lifetime; Core excitation; Atom- och molekylfysik;

    Sammanfattning : Atoms, molecules and clusters all constitute building blocks of macroscopic matter. Therefore, understanding the electronic and geometrical properties of such systems is the key to understanding the properties of solid state objects. LÄS MER

  3. 17. Faraday modulation spectroscopy : Theoretical description and experimental realization for detection of nitric oxide

    Författare :Jonas Westberg; Ove Axner; Gerard Wysocki; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Faraday modulation spectroscopy FAMOS ; Westberg-Wang-Axner WWA method; Fourier coefficients; Lineshape asymmetries; Nitric oxide NO ; fysik; Physics;

    Sammanfattning : Faraday modulation spectroscopy (FAMOS) is a laser-based spectroscopic dispersion technique for detection of paramagnetic molecules in gas phase. This thesis presents both a new theoretical description of FAMOS and experimental results from the ultra-violet (UV) as well as the mid-infrared (MIR) regions. LÄS MER

  4. 18. Formation and Dynamics of Molecular Excitons and their Fingerprints in Nonlinear Optical Spectroscopy

    Författare :Pär Kjellberg; Kemisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; supraledare; magnetisk resonans; spektroskopi; Physical chemistry; Fysikalisk kemi; Photochemistry; Fotokemi; Kondenserade materiens egenskaper:elektronstruktur; magnetiska och optiska ; egenskaper elektriska; supraconductors; magnetic resonance; relaxation; spectroscopy; Fysik; Chemistry; Kemi; Condensed matter:electronic structure; electrical; Physics; Redfield relaxation theory ; Inhomogeneous broadening ; Time-dependent density functional theory ; Conjugated polymers ; Three-pulse photon echo ; Molecular excitons ; magnetic and optical properties; Nonlinear spectroscopy ;

    Sammanfattning : An efficient transfer of energy in molecular systems has proven to be of fundamental importance both in nature and industrial applications. The ability of molecules to work together forming collective excitations, so-called excitons, plays a key role in for example the extraordinary fast energy transfer involved in the first steps of photosynthesis. LÄS MER

  5. 19. Aspects of Optical Broad Band Spectroscopy and Information Extraction - Applications in Medicine and Ecology

    Författare :Mikkel Brydegaard; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fluorescence Spectroscopy; Optical diagnostics; Electro-optics; Applied spectroscopy; Multispectral imaging; Optical spectroscopy; LIDAR; Remote sensing; Environmental monitoring; Chemometrics; Fysicumarkivet A:2012:Brydegaard Sörensen;

    Sammanfattning : The present thesis describes a number of aspects of modern electro-optical measurement technology also known as bio-photonics; this includes instrumentation, applications, sample interaction and data interpretation. The methods employed operate over several domains, and light measurements are discretized both in intensity, space, angle, time, polarization and energy. LÄS MER

  7. 20. Temporal Modulation in Fluorescence Spectroscopy and Imaging for Biological Applications

    Författare :Gustav Persson; Jerker Widengren; Jörg Enderlein; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; fluorescence; spectroscopy; microscopy; modulated excitation; intensity modulation; fluorescence correlation spectroscopy; transient states; molecular kinetics; Physics; Fysik;

    Sammanfattning : This thesis explores the benefits of intensity modulation for the purpose of extending the range of applications of fluorescence spectroscopy and imaging in cellular and molecular biology and medicine. Long-lived transient states of fluorescent molecules can, because of their long lifetimes, be used to detect subtle changes in the microenvironment of the molecule. LÄS MER