Sökning: "charge relaxation"

Visar resultat 11 - 15 av 84 avhandlingar innehållade orden charge relaxation.

  1. 11. Free Clusters Studied by Synchrotron-Based X-ray Spectroscopy: From Rare Gases to Metals

    Författare :Sergey Peredkov; Synkrotronljusfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; supraconductors; magnetic resonance; relaxation; spectroscopy; magnetic and optical properties; rare-gas clusters; Condensed matter:electronic structure; electrical; metal clusters; photoemission; synchrotron radiation; core-level spectroscopy; Auger decay; XPS; nano-particles; free clusters; egenskaper elektriska; spektroskopi; magnetisk resonans; magnetiska och optiska ; supraledare; Kondenserade materiens egenskaper:elektronstruktur;

    Sammanfattning : The main topic of this Thesis is the x-ray spectroscopic studies of free nano-clusters with size more than 10^3 atoms. The photoelectron spectroscopy experiments on rare gas and metal clusters were performed at beamline I411 at MAX-lab National Swedish synchrotron radiation facility. Free rare-gas clusters are simplest objects in cluster research. LÄS MER

  2. 12. Excited States of Carotenoids and Their Functions in Light Harvesting

    Författare :Donatas Zigmantas; Kemisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; spektroskopi; magnetic and optical properties; Carotenoids; light-harvesting; excited states; excitation energy transfer; femtosecond spectroscopy; supraconductors; magnetic resonance; electrical; Condensed matter:electronic structure; time-resolved fluorescence spectroscopy; magnetisk resonans; supraledare; magnetiska och optiska ; egenskaper elektriska; Kondenserade materiens egenskaper:elektronstruktur; relaxation; spectroscopy;

    Sammanfattning : The research presented in this thesis is focused on characterization of photophysical properties of lowest singlet excited states of carotenoids and their functions in the process of photosynthetic light harvesting. It is shown that the various light-harvesting complexes utilize different strategies to achieve efficient energy transfer from carotenoids to (bacterio)chlorophylls. LÄS MER

  3. 13. Studies of acoustic waves, noise and charge pumping using single-electron devices

    Författare :Martin Gustafsson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; single-electron pump; single-electron transistor; surface acoustic wave; single-electron devices; charge pumping; TLF; SINIS turnstile; electrometer; two-level fluctuator; single-photon detector; noise; SAW; SET;

    Sammanfattning : This thesis covers a range of experiments on single-electron devices, electrical circuits that utilize the discreetness of the electron charge. The Single-Electron Transistor (SET) is of special importance among these, being the most sensitive electrometer demonstrated, and sufficiently mature to serve as a building block in sensors and detectors for physical phenomena that can be transformed into charge signals. LÄS MER

  4. 14. Water-Induced Charge Transport in Microcrystalline Cellulose

    Författare :Martin Nilsson; Maria Strømme; Göran Alderborn; Jürgen Einfeldt; Uppsala universitet; []
    Nyckelord :Materials science; Materialvetenskap;

    Sammanfattning : Microcrystalline cellulose (MCC) is the most frequently used excipient for direct compaction of tablets within the pharmaceutical industry. It has earlier been indicated that the interactions between the hydration shell – surrounding the drug molecules in an MCC tablet – and the cellulose regulate the speed of the drug release process. LÄS MER

  5. 15. An X-ray Based Spectroscopic Study of Structure Influencing Electrons : Fragmentation, Ultrafast Charge Dynamics and Surface Composition

    Författare :Geethanjali Gopakumar; Olle Björneholm; Carl Caleman; Isaak Unger; Ruth Signorell; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fragmentation; ICD; ETMD; Ultrafast electron dynamics; Surface propensity;

    Sammanfattning : The structure of biomolecules, such as proteins, is intimately connected to the function of the molecules. These structures are often studied using X-ray diffraction. However, the interaction of the X-ray photons with the molecule can excite or ionize its electrons which in turn can causes changes in the molecular structure. LÄS MER