Sökning: "electron paramagnetic resonance"

Visar resultat 16 - 20 av 52 avhandlingar innehållade orden electron paramagnetic resonance.

  1. 16. Zero-Field Splitting in Gd(III) complexes : Towards a molecular understanding of paramagnetic relaxation

    Författare :Shehryar Khan; Michael Odelius; Arnold Maliniak; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Zero-Field Splitting; Relaxation; Quantum Chemistry; Molecular Dynamics; Gd III ; kemisk fysik; Chemical Physics;

    Sammanfattning : The prime objectives of contrast agents in Magnetic Resonance Imaging(MRI) is to accelerate the relaxation rate of the solvent water protons in the surrounding tissue. Paramagnetic relaxation originates from dipole-dipole interactions between the nuclear spins and the fluctuating magnetic field induced by unpaired electrons. LÄS MER

  3. 17. Electron paramagnetic resonance and biochemical studies of red-ox properties of the diferric/radical center in mouse and Mycobacterium tuberculosis ribonucleotide reductase R2 proteins

    Författare :Albert Davydov; Marc Fontecave; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biophysics; biofysik;

    Sammanfattning : Ribonucleotide reductase (RNR) catalyses the reduction of all four ribonucleotides to the corresponding deoxyribonucleotides that are used by the cells for DNA synthesis. The active enzyme from mouse, Mycobacterium tuberculosis (M. tuberculosis) and aerobically grown E. LÄS MER

  4. 18. Mechanisms and time course of cell death in embryonic nigral tissue and intrastriatal transplants

    Författare :Mia Emgård; Neurobiologi; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; hypothermia; resveratrol; free radicals; ultrastructure; electron microscopy; mesencephalic; transplantation; rat; Parkinson s disease; dopamine; Neurology; neuropsychology; neurophysiology; Neurologi; neuropsykologi; neurofysiologi;

    Sammanfattning : Parkinson’s disease (PD) is the second most common neurodegenerative disorder and severely affects about one in a hundred persons over the age of fifty years. In PD, there is a reduced striatal concentration of the neurotransmittor dopamine, mainly caused by a degeneration of the dopaminergic neurons in the substantia nigra. LÄS MER

  5. 19. Combined Quantum Mechanical and Molecular Dynamics study of paramagnetic complexes : Towards an understanding of electronic spin relaxation

    Författare :Shehryar Khan; Michael Odelius; Jozef Kowalewski; Juha Vaara; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; molecular dynamics; quantum chemistry; zero-field splitting; kemisk fysik; Chemical Physics;

    Sammanfattning : The prime objectives of contrast agents in Magnetic Resonance Imaging (MRI) is to accelerate the relaxation rate of the solvent water protons in the surrounding tissue. Paramagnetic relaxation originates from dipole-dipole interactions between the nuclear spins and the fluctuating magnetic field induced by unpaired electrons. LÄS MER

  7. 20. Metal Oxide Nanoparticles for Contrast Enhancement in Magnetic Resonance Imaging : Synthesis, Functionalization and Characterization

    Författare :Maria Ahrén; Kajsa Uvdal; Jan Kehr; Linköpings universitet; []
    Nyckelord :;

    Sammanfattning : This thesis work focuses on the design and production of nanoparticle based contrast agents for signal enhancement in magnetic resonance imaging (MRI). Three different synthesis routes are explored, primarily to produce crystalline gadolinium oxide (Gd2O3) nanoparticles, and surface modification is done to obtain stable, dispersible, biocompatible probes inducing high proton relaxivities. LÄS MER