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MR spectroscopy of the heart in vivo
Drobný, Miloslav ; Englich, Jiří (advisor) ; Herynek, Vít (referee)
The presented thesis deals with the use of MR spectroscopy methods for the study of heart metabolism, namely the determination of the lipid content in the heart tissue. The aim of the thesis was the optimization of the examination protocol for the use in the routine examination of patients. The heart examination by means of MR spectroscopy is due to movements caused by the heart rhythm and breathing very challenging. We have, therefore, proposed the measurement protocol, when the measurement is controlled both by ECG signal and the signal monitoring breathing of the examined subject. To achieve sufficient quality of MR spectra we also proposed the use of an advanced method (GREshim) for the adjustment of the homogeneity of the static magnetic field. Using the optimized examination protocol we have examined a group of 14 healthy volunteers. An average content of lipids in the myocardium equal to 0,7 % as determined from the performed measurements is in agreement with published data.
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The study of spin-lattice and spin-spin NMR relaxation of 1H nuclei in water
Dvořák, Petr ; Englich, Jiří (advisor) ; Lang, Jan (referee)
The dependences of spin-lattice and spin-spin relaxation rates of 1H nuclei on the concentration of H2O in H2O-D2O mixtures were measured using experimental methods of high resolution NMR. Before this measurement, we investigated the influence of radiation damping, paramagnetic impurities and temperature upon measurement of relaxation rates, as well as methods of its reduction. We also measured the dependences of spin-lattice and spin-spin relaxation rates of 17O nuclei on the concentration of H2O in H2O-D2O mixtures. We discuss the results, aiming to verify the accurancy of prior interpretations and to assess the influence of chemical exchange.
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Spin-lattice and spin-spin NMR relaxation of 1H nuclei in deuterated etanol and butanol doped by TEMPO radical
Matoušek, Jan ; Englich, Jiří (advisor) ; Štěpánková, Helena (referee)
The thesis deals with study of deuterated ethanol and butanol (ethyl-D5 alcohol, butyl-D9 alcohol) with a small amount (0 to 1.5% weight) of dissolved stable free radical TEMPO by methods of NMR. This system is used in polarized targets for high energy experiments. The linear dependence of spin-lattice and spin-spin relaxation rate of hydrogen nuclei from OH group of an alcohol on the radical concentration and dependence of the relaxation rates decreasing with temperature (in range from 250 to 298K) were obtained. The T1/T2 ratio from 1.3 to 2.0 was calculated. This was interpreted as an effect of a contact interaction via hydrogen bond between alcohol and radical molecules. The linear dependence of the resonance frequency of hydrogen nuclei from OH group on the radical concentration was obtained. The slope of the dependence line didn't change with temperature. Using this dependence the hyperfine constant of the interaction between hydrogen nucleus and the free electron of the radical was estimated approximately 8·10-28 J. It was found out that the lifetime of the hydrogen bonds between alcohol and radical molecules are about 10-11 s or longer.
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Study of LaCuAl3 structure by means of nuclear magnetic and quadrupole resonance
Sgallová, Ráchel ; Chlan, Vojtěch (advisor) ; Englich, Jiří (referee)
In the presented bachelor thesis the structure of LaCuAl3 was studied on a series of metallic powder samples LaCuxAl4−x, x = 0,75; 0,9; 1 and 1,1 especially with respect to the local symetry of La atoms. 63 Cu, 65 Cu, 27 Al and 139 La nuclear magnetic resonance spectra were measured at room tempera- ture in external magnetic eld of 9,4 T. Some of the measured spectra were compared with simulated ones in order to access the number of nonequiva- lent atoms in the structure. Furthermore, the effect of Al/Cu stoichiometry on nuclear magnetic resonance spectra was observed and diccussed. 1
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Study of LaCuAl3 structure by means of nuclear magnetic and quadrupole resonance
Sgallová, Ráchel ; Chlan, Vojtěch (advisor) ; Englich, Jiří (referee)
In the presented bachelor thesis the structure of LaCuAl3 was studied on a series of metallic powder samples LaCuxAl4−x, x = 0,75; 0,9; 1 and 1,1 especially with respect to the local symetry of La atoms. 63 Cu, 65 Cu, 27 Al and 139 La nuclear magnetic resonance spectra were measured at room tempera- ture in external magnetic eld of 9,4 T. Some of the measured spectra were compared with simulated ones in order to access the number of nonequiva- lent atoms in the structure. Furthermore, the effect of Al/Cu stoichiometry on nuclear magnetic resonance spectra was observed and diccussed. 1
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MR spectroscopy of the heart in vivo
Drobný, Miloslav ; Englich, Jiří (advisor) ; Herynek, Vít (referee)
The presented thesis deals with the use of MR spectroscopy methods for the study of heart metabolism, namely the determination of the lipid content in the heart tissue. The aim of the thesis was the optimization of the examination protocol for the use in the routine examination of patients. The heart examination by means of MR spectroscopy is due to movements caused by the heart rhythm and breathing very challenging. We have, therefore, proposed the measurement protocol, when the measurement is controlled both by ECG signal and the signal monitoring breathing of the examined subject. To achieve sufficient quality of MR spectra we also proposed the use of an advanced method (GREshim) for the adjustment of the homogeneity of the static magnetic field. Using the optimized examination protocol we have examined a group of 14 healthy volunteers. An average content of lipids in the myocardium equal to 0,7 % as determined from the performed measurements is in agreement with published data.
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Low temperature proton polarized target for nucleon structure studies at COMPASS
Pešek, Michael ; Finger, Miroslav (advisor) ; Englich, Jiří (referee)
Title: Low temperature proton polarized target for nucleon structure studies at COMPASS Author: Michael Pešek Department / Institute: Department of Low temperature Physics Supervisor of the bachelor thesis: prof. Ing. Miroslav Finger, DrSc., Department of Low Temperature Physics Abstract: Overview of basics of deep inelastic scattering and process of dynamic nuclear polarization with emphasis to importance of precise polarization determination for nucleon spin structure studies are given. This is followed by description of COMPASS experiment with emphasis given to low temperature polarized target. General procedure of NMR data analysis is given and finally polarization for run 2010 and relaxations rates are determined. Keywords: nucleon structure, polarized proton target, low temperatures, NMR technique
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Spin-lattice and spin-spin NMR relaxation of 1H nuclei in deuterated etanol and butanol doped by TEMPO radical
Matoušek, Jan ; Englich, Jiří (advisor) ; Štěpánková, Helena (referee)
The thesis deals with study of deuterated ethanol and butanol (ethyl-D5 alcohol, butyl-D9 alcohol) with a small amount (0 to 1.5% weight) of dissolved stable free radical TEMPO by methods of NMR. This system is used in polarized targets for high energy experiments. The linear dependence of spin-lattice and spin-spin relaxation rate of hydrogen nuclei from OH group of an alcohol on the radical concentration and dependence of the relaxation rates decreasing with temperature (in range from 250 to 298K) were obtained. The T1/T2 ratio from 1.3 to 2.0 was calculated. This was interpreted as an effect of a contact interaction via hydrogen bond between alcohol and radical molecules. The linear dependence of the resonance frequency of hydrogen nuclei from OH group on the radical concentration was obtained. The slope of the dependence line didn't change with temperature. Using this dependence the hyperfine constant of the interaction between hydrogen nucleus and the free electron of the radical was estimated approximately 8·10-28 J. It was found out that the lifetime of the hydrogen bonds between alcohol and radical molecules are about 10-11 s or longer.
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The study of spin-lattice and spin-spin NMR relaxation of 1H nuclei in water
Dvořák, Petr ; Englich, Jiří (advisor) ; Lang, Jan (referee)
The dependences of spin-lattice and spin-spin relaxation rates of 1H nuclei on the concentration of H2O in H2O-D2O mixtures were measured using experimental methods of high resolution NMR. Before this measurement, we investigated the influence of radiation damping, paramagnetic impurities and temperature upon measurement of relaxation rates, as well as methods of its reduction. We also measured the dependences of spin-lattice and spin-spin relaxation rates of 17O nuclei on the concentration of H2O in H2O-D2O mixtures. We discuss the results, aiming to verify the accurancy of prior interpretations and to assess the influence of chemical exchange.
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