Sökning: "Spin diffusion"

Visar resultat 1 - 5 av 60 avhandlingar innehållade orden Spin diffusion.

  1. 1. Nuclear Magnetic Resonance for Diffusion Imaging Development and evaluation of spin-echo-based pulse sequences for in vivo studies of water self-diffusion

    Detta är en avhandling från Department of Radiation Physics, Lund university

    Författare :Sara Brockstedt; Lund University.; Lunds universitet.; [1998]
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; perfusion fraction; electrocardiographic triggering; segmented EPI SEPI ; echo-planar imaging EPI ; fast spin-echo FSE ; spin-echo SE ; navigator echoes; phase corrections; diffusion; Magnetic resonance; MRI; ischaemic stroke; Medicine human and vertebrates ; Medicin människa och djur ;

    Sammanfattning : The interest in diffusion imaging with nuclear magnetic resonance techniques has increased during the last few years. The main reason is the possibility of early diagnosis of acute ischaemic stroke, at a time when conventional MR techniques and computerised tomography fail. LÄS MER

  2. 2. NMR diffusion studies on lyotropic liquid crystalline systems

    Detta är en avhandling från Umeå : Umeå universitet

    Författare :Greger Orädd; Umeå universitet.; [1994]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Diffusion; pulsed field gradient; liquid crystalline systems; lipid lateral diffusion; cubic phases; peptide-lipid interactions; hydrophobic mismatch; permeability;

    Sammanfattning : The pulsed field gradient fourier transform nuclear magnetic resonance (PFG-FTNMR) method to measure translational diffusion coefficients in multicomponent systems has been applied to amphiphilic molecules forming liquid crystalline phases.By analyzing the concentration dependence of the diffusion coefficients of water and amphiphile in a micellar system of N,N-dimethyldodecy lamine oxide (DDAO) in water it was possible to conclude that the micelles formed were polydisperse in size and shape. LÄS MER

  3. 3. Diffusion MRI of Small Ischemic Brain Lesions: Technical aspects, clinical experiences and diagnostic criteria

    Detta är en avhandling från Department of Diagnostic Radiology, Lund University

    Författare :Bo Geijer; Lund University.; Lunds universitet.; [2001]
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; radiology; Clinical physics; Metastasis; ADC; b; Infarct; MRI; Ischemia; Diffusion-Weighted; Diffusion; tomography; medical instrumentation; Klinisk fysiologi; radiologi; tomografi; medicinsk instrumentering;

    Sammanfattning : Purpose: To compare the visualization of small ischemic brain lesions using diffusion using diffusion-weighted (DW) MRI and conventional imaging, with special regard to diagnostic efficiency. Imaging features of lesions of different ages, diagnostic limitations and technical principles were also investigated. LÄS MER

  4. 4. Superdiffusive Spin Transport and Ultrafast Magnetization Dynamics Femtosecond spin transport as the route to ultrafast spintronics

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Marco Battiato; Uppsala universitet.; [2013]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ultrafast magnetisation dynamics; anomalous diffusion; femtosecond dynamics; magnetism; Materialvetenskap; Materials Science;

    Sammanfattning : The debate over the origin of the ultrafast demagnetization has been intensively active for the past 16 years. Several microscopic mechanisms have been proposed but none has managed so far to provide direct and incontrovertible evidences of their validity. LÄS MER

  5. 5. WAVELET NOISE REDUCTION AND VASCULAR WATER TRANSPORT MODELLING : APPLICATIONS TO DIFFUSION AND PERFUSION MRI

    Detta är en avhandling från Lunds universitet

    Författare :Adnan Bibic; Lund University.; Lunds universitet.; [2018-11]
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; cerebral blood flow; perfusion; diffusion; arterial spin labelling; wavelets; filtering; denoising; blood-brain barrier; permeability; Fysicumarkivet A:2018:Bibic;

    Sammanfattning : Magnetic resonance imaging (MRI) is a powerful medical imaging technique, used to detect and characterise a range of diseases and conditions. It is based on the use of a strong static magnetic field in combination with magnetic field gradients and pulsed radiofrequency electromagnetic fields to visualise various organs and structures in the body according to their morphology or function. LÄS MER