Search for dissertations about: "relaxation time"

Showing result 1 - 5 of 367 swedish dissertations containing the words relaxation time.

2. 1. Theory of water-proton spin relaxation in complex biological systems

   Author : Zhiwei Chang; Biofysikalisk kemi; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; spin relaxation theory; immobilized macromolecules; magnetic relaxation dispersion; integral longitudinal relaxation rate; stochastic Liouville equations; multi-spin systems; cross-mode relaxation; spectral density functions;

   Abstract : In complex biological systems (e.g. gels, cross-linked proteins and biological tissues), the longitudinal spin relaxation of water protons is primarily induced by exchange-mediated orientational randomization (EMOR) of intra- and intermolecular magnetic dipole-dipole couplings. READ MORE

4. 2. Paramagnetic relaxation reagents : nuclear magnetic resonance studies of preferential solvation

   Author : Hans Grahn; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES;

   Abstract : The interactions between neutral paramagnetic relaxation reagents (PARR's) and certain aromatic compounds have been studied by 1H and 13 C spin-lattice relaxation time measurements. In media such as cyclohexane and carbon tetrachloride, Cr(acac)3 becomes preferentially solvated by aromatic solutes. READ MORE

5. 3. Measurement of T1 relaxation time in lungs - Preclinical and clinical MRI applications to COPD

   Author : Daniel Alamidi; Göteborgs universitet; []
   Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Magnetic Resonance Imaging; biomarker; tobacco smoke; mouse; smoking; lung imaging; Chronic Obstructive Pulmonary Disease; ultrashort echo time UTE ; T1 mapping; longitudinal relaxation time;

   Abstract : Monitoring of regional lung function in clinical trials of chronic obstructive pulmonary disease (COPD) requires alternative endpoints beyond global pulmonary function tests (PFTs), which is the most common approach for diagnosing lung function abnormalities in humans. A promising magnetic resonance imaging (MRI) biomarker of lung disease in humans and animals is the T1 relaxation parameter. READ MORE

6. 4. Adaptive time-integration for goal-oriented and coupled problems

   Author : Peter Meisrimel; Numerisk analys; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; time-adaptivity; goal-oriented problems; error estimation; coupled problems; waveform relaxation; asynchronous methods; conjugate heat transfer;

   Abstract : We consider efficient methods for the partitioned time-integration of multiphysics problems, which commonly exhibit a multiscale behavior, requiring independent time-grids. Examples are fluid structure interaction in e.g., the simulation of blood-flow or cooling of rocket engines, or ocean-atmosphere-vegetation interaction. READ MORE

7. 5. Formation and Dynamics of Molecular Excitons and their Fingerprints in Nonlinear Optical Spectroscopy

   Author : Pär Kjellberg; Kemisk fysik; []
   Keywords : 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 ;

   Abstract : 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. READ MORE