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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

The hydrogen atom in a magnetic field

Kirkman, Thomas William. January 1982 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
22

Théorie d'une métrologie du champ magnétique terrestre basée sur la résonance de noyaux atomiques polarisés.

Bonnet, Georges. January 1900 (has links)
Thèse--Grenoble.
23

Statistics of the Earth's magnetic field with applications /

Walker, Andrew D., January 1997 (has links)
Thesis (Ph. D.)--University of California, San Diego, 1997. / Vita. Includes bibliographical references.
24

Effects of static magnetic fields on mammalian cells

Yuan, Hang. Haik, Yousef, January 2005 (has links)
Thesis (Ph. D.)--Florida State University, 2005. / Advisor: Dr. Yousef Haik, Florida State University, College of Engineering, Dept. of Chemical and Biomedical Engineering. Title and description from dissertation home page (viewed Sept. 27, 2005). Document formatted into pages; contains xiii, 159 pages. Includes bibliographical references.
25

Calibration of a magnetic field probe as a diagnostic for laser-produced plasma an honors project /

Morton, Lucas A. January 1900 (has links) (PDF)
Honors project (B.A.) -- Carson-Newman College, 2010. / Project advisor: Dr. Michael Seale ; Research advisor: Chris Niemann. Includes bibliographical references (pp. 24-25).
26

Diffusion in the levitated toroidal octupole

Greenwood, James Robert, January 1975 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1975. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Bibliographical references.
27

Studies of plasma oscillations and instabilities in magnetic fields

Rumsby, P. T. January 1968 (has links)
No description available.
28

An experimental study of static magnetic field effect on free diffusion of saccharides in aqueous solution

Atwal, Virinder S. January 1990 (has links)
The purpose of this work was to investigate experimentally the effects of an externally applied magnetic field on free diffusion of saccharides in aqueous solution. The diffusion coefficients of simple saccharides (deoxyribose, D(-)ribose, D(+)xylose, D-glucose, D-galactose, D(-)fructose, lactose, sucrose, maltose, raffinose) diffusing through a 0.4 micron pore diameter Nuclepore membrane were measured in applied magnetic field strengths ranging from zero to 1.1 T. The applied magnetic field strength was the only variable in these experiments. The initial saccharide concentration difference across the membrane was one percent by weight. The experiments were conducted at a constant temperature of 25 ±0.1° C. The diffusion coefficient was obtained by means of a modified Rayleigh interferometer-laser system. A Rayleigh interferometer measured refractive index profiles of dilute saccharide solutions contained in a diffusion cell. Refractive index profiles were converted to concentration profiles which were then used to calculate mass fluxes and the corresponding binary diffusion coefficients. A study of saccharide-water interactions indicates that these interactions are very complex in nature and that saccharide hydration depends not only on the number of equatorial hydroxyl (e-OH) groups in a saccharide molecule but also on their spatial orientation. The saccharide-water solutions exhibit properties that are considered to be the result of two factors (1) the elongated (non-spherical) shape of the oligosaccharides (2) effect of monosaccharides on the local water structure (i.e their ability to either enhance or destroy the local water structure). The observed magnetic field effect on diffusion coefficients of saccharides shows a strong dependency on these two factors. A decrease in binary diffusion coefficients ranging from two to eighteen percent has been observed for applied magnetic fields up to 1.1 T. The diffusion coefficients evaluated at zero field strength (earth's magnetic field) agreed with literature values to within one percent. The noted decrease in diffusivity of monosaccharides (ribose, xylose, galactose, glucose) becomes larger with an increase in the number of equatorial hydroxyl (e-OH number) groups in the saccharide molecule. This is because an increase in e-OH number increases the microviscosity of the saccharide molecule (structure making or stabilising effect). Deoxyribose and fructose, on the other hand, are considered to be structure breakers. The observed decrease in diffusivity for these saccharides induced by the applied magnetic field seem to be the result of a general stabilizing effect of the applied field on the originally less stable saccharide-water solution. The effect of applied magnetic field on the binary diffusion coefficients of oligosaccharides (sucrose, lactose, maltose, raffinose) correlates with the e-OH numbers as well. In this case, however, the observed decrease in diffusivities is due directly to the orientation of these molecules by the externally applied magnetic field (Cotton-Mouton effect). The same membrane was used to study one complete saccharide system, six runs, (made possible by the changes introduced into the design of diffusion cell and diffusion cell holder in this work) so that variation between membranes would not be a factor. The new experimental procedure resulted in significant reduction in data scatter and highly improved measurement accuracy. Finally, it was shown that the membrane only presented an area reduction to diffusion i.e. the transport process through the membrane followed the assumption of free diffusion. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate
29

Field tolerances associated with some resonances in the triumf cyclotron

Bolduc, Jean Louis January 1972 (has links)
This thesis is concerned with tolerances for magnetic field imperfections in the TRIUMF cyclotron set by the betatron oscillation resonances v[formula omitted] = 1.0, v[formula omitted] – v[formula omitted] = 1.0 and v[formula omitted] = 1.5. These resonances, encountered during acceleration, can lead to undesirable growth in the amplitudes of the betatron oscillations. We first derive equations of motion that take into account non-linear terms and field imperfections, and show how resonance conditions may occur. These conditions were simulated in our orbit codes and numerical calculations were made to determine the tolerances they impose on the magnetic field. We have made a detailed investigation of the effect on the behaviour of the beam of first harmonic bumps at radii less than 150 in. The first harmonic tolerance of 0.1 G to produce an increase in the radial amplitude of 0.1 in. is in agreement with analytical calculations. We have also shown that this tolerance, too small to be seen in the magnetic field survey, may be achieved by suitable adjustments in the harmonic coil settings. Tolerances on the second harmonic imperfection are also presented. To determine the tolerances set by the coupled resonance v[formula omitted] – v[formula omitted] = 1.0, we have simulated a first harmonic twist in the median plane. The results show that, for high current poor resolution experiments, the magnitude of the twist on entering the resonance is of no importance, provided the amplitudes of the radial and vertical betatron oscillations are not much larger than the estimate of 0.2 in. For high resolution experiments, the tolerances on the slope of the twist are of the order of a few mrad. Analytical estimates of these tolerances are also presented. Finally, we have determined that the v[formula omitted] = 1.5 resonance sets an upper limit to the gradient of the third harmonic of about 0.2 G/in., which produces a 20% increase in the radial betatron amplitude. / Science, Faculty of / Physics and Astronomy, Department of / Graduate
30

Effect of Sample Geometry on Magnetomorphic Oscillations in the Hall Effect in Cadium at Liquid-Helium Temperatures

Fielder, James Thomas 06 1900 (has links)
This thesis presents observations on size-effect oscillations in the Hall effect in an oriented single crystal of highly pure cadmium at liquid-helium temperatures. All measurements were made in transverse magnetic field.

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