Department of Physics (Fredericton)

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Microwave studies of 17O methanol
Microwave studies of 17O methanol
by Peter Martin Bance, A Stark-modulation microwave spectrometer was constructed including the necessary vacuum line and microwave detection system. The microwave spectrum of 17O methanol was then studied in the 28 to 33 GHZ and the 44 to 51 GHZ regions in an effort to learn more about the rotational and torsional energy level structure of the molecule. The quantum mechanics of molecular rotation and angular momentum in particular were explored along with a physical phenomenon known as the Stark effect. The frequencies of many previously unpublished lines were measured using the assembled apparatus and all possible assignments of quantum numbers made based on Stark splittings. The component of the dipole moment along the a-axis of the molecule (μa) in its first excited torsional state was calculated based on observed Stark shifts of the various M components for the J(K) = 2(0) - 3(1) El, b-type transition., Appendices numbered I.1- III.4
Microwave studies of methyl alcohol and methyl amine
Microwave studies of methyl alcohol and methyl amine
by Tony James Noble, The microwave spectra of methyl alcohol and methyl amine were studied with various goals in mind. An attempt was made to further verify the existence of a hypothetical X state. However, due to poor resolution no additional information was obtained. It was also attempted to add additional support to the assignment of K = 1 →O E2 to a weak Q-branch series by looking for other transitions which the assignment forced to exist. No substantial evidence was found although a transition was seen near an expected location but could not be positively identified. A number of lines in the 60 to 80 GHz region of the methyl amine spectrum were measured. These lines fit a Q-branch series. Two large lines were found close together which is of significance as they can be easily identified by their separation and relative intensities.
Microwave studies of methyl amine
Microwave studies of methyl amine
by John Stephen Pitre, The microwave spectrum of methyl amine was studied with the intent of extending the assignments for the Q branch. Some lines were found but none beyond the J=8 transition. A number of lines in the 100 to 130 MHz region were measured and these were compared to the theoretical values for the quadrupole splitting, with the intent of eventually determining more accurate values for the coupling constants of methyl amine., 3 unnumbered pages after the last numbered page
Mössbauer spectroscopy: survey and application to Fe2As
Mössbauer spectroscopy: survey and application to Fe2As
by Michel Royer, The fundamental concepts required for a basic understanding of Mössbauer spectroscopy are presented. These include the principle of recoilless events, the instrumentation needed for a Mössbauer laboratory, and the physical meanings of parameters used in Mössbauer studies. A model is developed that can describe spectra in which time dependent effects are negligible. An experimental application is given, in the form of a study of Fe2As in which this model is used. There exists some controversy over the values of certain parameters which describe Fe2As; it was hope that a computer fitting program based on this model would provide conclusive information about the parameters (is n non-zero?). This work did not find definitive values of the parameters, but the study of Fe2As and of the methods used to try to solve the questions over the controversial parameters lead to a better grasp of Mössbauer spectroscopy, of its power, and of its limitations.
NMR measurements of self-diffusion coefficients of degassed water
NMR measurements of self-diffusion coefficients of degassed water
by Andrew King, In this project I have measured the molecular self-diffusion coefficient of water in order to quantify the effects of dissolved gas concentration upon self-diffusion. It has been shown that degassing water samples has enhanced the stability of oil-in- water emulsions formed without the aid of stabilizers such as surfactants and polymers 1. Degassing enhances water's ability to work as a solvent of non-polar molecules. There are electrical conductivity changes in the water when it is completely degassed; such a change demonstrates that there is a change in molecular structure. This leads to an interest in the self-diffusion behaviour of the water under these conditions2. The project began with optimization of the phase cycling scheme for the NMR Cotts-13 interval sequence, which measures self-diffusion in the presence of local magnetic field inhomogeneity. This technique development allowed us to measure the self-diffusion coefficient of the water samples that are degassed and non-degassed.
Nonlinear characterization of NMR systems by Wiener kernels
Nonlinear characterization of NMR systems by Wiener kernels
by Michael James Hogan, Stochastic excitation of nuclear magnetic resonance, NMR, systems is a relatively new technique used to obtain NMR spectra. Instead of the conventional monochromatic radiation sources, samples are excited with a band limited white noise spectrum. The familiar Bloch equation can be derived for a nucleus in a constant magnetic field subjected to a stochastic perturbation. The method employed by Ernst (1) to solve these equations is examined in this report. In order to characterize an NMR system, the magnetization is expressed as an infinite sum of increasing order functionals called the Wiener series. Equations, which may be solved on a computer, are derived for the first and third Wiener kernel. Computer programs to implement these equations are written and tested with several test systems. The programs are applied to NMR signals obtained from a water sample using various values of input intensity to verify the saturation curve predicted from the theory. An NMR spectrum is also obtained for noise excitation of the hydrogen nuclei in a sample of 2, 3-dibromothiophene.
Nuclear spin relaxation study of deuterated wet lysozyme
Nuclear spin relaxation study of deuterated wet lysozyme
by Frederick Gordon Yeomans, 2 unnumbered pages after last numbered page
Optical optical double resonance of Li2
Optical optical double resonance of Li2
by Lisa Steele, Appendix numbered from A1- A16

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