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Electrolysis of Aluminum Solutions in a Magnetic Field

Description: This investigation is an attempt to verify the original work done by George Antonoff and Anne Rowley, and to contribute specific data on the action of a magnetic field on aluminum cells. Experiments of the type they have described have been performed and an extensive set of data has been collected. It was thought that if the results of Antonoff and Rowley could be duplicated, further investigation would be warranted. However, the experiments have produced negative results. These results are des… more
Date: May 1950
Creator: Wood, Charles E.
Item Type: Refine your search to only Thesis or Dissertation
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Proton Nuclear Magnetic Resonance in Mica

Description: The experiments to be described here were undertaken for the purpose of determining, if possible, by NMR techniques whether or not the hydroxyl protons in mica are bound in a regular crystalline array, and, if so, whether or not the hydroxyl protons occur in reasonably isolated pairs as in waters of hydration.
Date: May 1962
Creator: Townsend, Don H.
Item Type: Refine your search to only Thesis or Dissertation
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The Dielectric Constant of Galvinoxyl

Description: The molecules in many substances are know to undergo at characteristic temperatures a change in their rotational freedom in the solid state, signifying either a change in structure of the material of the onset of limited rotation of the molecule about some symmetry axis. The purpose of this research was to determine from dielectric constant measurements over the 100°K-420°K temperature range whether or not the organic free radical galvinoxyl and its diamagnetic parent molecule, dihydroxydipheny… more
Date: May 1968
Creator: Mizell, Michael E.
Item Type: Refine your search to only Thesis or Dissertation
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Cross-Section at 15.6 and 16.1 MeV

Description: The intent of this investigation is the determination of the values of the Cs-133 (n,2n)Cs-132 cross-section at neutron energies of 15.6 and 16.1 MeV. Neutrons of this energy are produced with comparative ease by means of the D-T reaction, in which deuterons of energy 500 and 750 keV, respectively, are impingent upon a tritium target.
Date: May 1969
Creator: Pepper, George H.
Item Type: Refine your search to only Thesis or Dissertation
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Cross Section Measurements in Praseodymium-141 as a Function of Neutron Bombarding Energy

Description: Using the parallel disk method of activation analysis, the (n,2n) reaction cross section in 141-Pr was measured as a function of neutron energy in the range 15.4 to 18.4 MeV. The bombarding neutrons were produced from the 3-T(d,n)4-He reaction, where the deuterons were accelerated by the 3-MV Van de Graff generator of the North Texas Regional Physics Laboratory in Denton, Texas.
Date: May 1971
Creator: Marsh, Stephen Addison
Item Type: Refine your search to only Thesis or Dissertation
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Virial Theorem for a Molecule

Description: The usual virial theorem, relating kinetic and potential energy, is extended to a molecule by the use of the true wave function. The virial theorem is also obtained for a molecule from a trial wave function which is scaled separately for electronic and nuclear coordinates.
Date: May 1972
Creator: Ranade, Manjula A.
Item Type: Refine your search to only Thesis or Dissertation
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Electrical Conductivity in Thin Films

Description: This thesis deals with electrical conductivity in thin films. Classical and quantum size effects in conductivity are discussed including some experimental evidence of quantum size effects. The component conductivity along the applied electric field of a thin film in a transverse magnetic field is developed in a density matrix method.
Date: May 1973
Creator: Meyer, Frederick Otto
Item Type: Refine your search to only Thesis or Dissertation
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Electron Density and Collision Frequency Studies Using a Resonant Microwave Cavity as a Probe

Description: Electron densities and collision frequencies were obtained on a number of gases in a dc discharge at low pressures (0.70-2mm of Hg). These measurements were performed by microwave probing of a filament of the dc discharge placed coaxially in a resonant cavity operating in a TM₀₁₀ mode. The equipment and techniques for making the microwave measurements employing the resonant cavity are described. One of the main features of this investigation is the technique of differentiating the resonance sig… more
Date: May 1973
Creator: Freeman, Ronald Harold
Item Type: Refine your search to only Thesis or Dissertation
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A Calculation of the Excitation Spectrum of Superfluid Helium-4

Description: The Hartree-Fock-Bogoliubov theory of homogeneous boson systems at finite temperatures is rederived using, a free energy variational principle. It is shown that a t-matrix naturally emerges in the theory. Phenomenological modifications are made (1) to remove the energy gap at zero momentum, and (2) to eliminate the Hartree-Fock-like terms, which dress the kinetic energy of the particle. A numerical calculation of the energy spectrum is made over a temperature range of 0.00 to 3.14 K using the M… more
Date: May 1974
Creator: Goble, Gerald W.
Item Type: Refine your search to only Thesis or Dissertation
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K-Shell Ionization Cross Sections of Selected Elements from Ag to La for Proton Bombardment from 0.6 to 2.0 MeV

Description: The K-shell x-ray and ionization cross sections are measured for protons on Ag, Cd, Sn, Sb, Te, Ba, and La over the ion energy range of 0.6 to 2.0 MeV. The data are compared to the predictions of the PWBA, the PWBA with corrections for binding energy and/or Coulomb deflection, the BEA, and the constrained BEA predictions. In general, the non-relativistic PWBA with binding energy correction gives the best overall agreement with the measurements of proton-induced x-ray processes for the K-shell o… more
Date: May 1974
Creator: Khelil, Najat Arafat
Item Type: Refine your search to only Thesis or Dissertation
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Microwave Properties of Liquids and Solids, Using a Resonant Microwave Cavity as a Probe

Description: The frequency shifts and Q changes of a resonant microwave cavity were utilized as a basis for determining microwave properties of solids and liquids. The method employed consisted of varying the depth of penetration of a cylindrical sample of the material into a cavity operating in the TM0 1 0 Mode. The liquid samples were contained in a thin-walled quartz tube. The perturbation of the cavity was achieved by advancing the sample into the cavity along the symmetry axis by employing a micrometer… more
Date: May 1974
Creator: Hong, Ki H.
Item Type: Refine your search to only Thesis or Dissertation
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Density Profile of a Quantized Vortex Line in Superfluid Helium-4

Description: The density amplitude of an isolated quantum vortex line in superfluid 4He is calculated using a generalized Gross-Pitaevskii (G-P) equation. The generalized G-P equation for the order parameter extends the usual mean-field approach by replacing the interatomic potential in the ordinary G-P equation by a local, static T matrix, which takes correlations between the particles into account. The T matrix is a sum of ladder diagrams appearing in a diagrammatic expansion of the mean field term in an … more
Date: May 1975
Creator: Harper, John Howard
Item Type: Refine your search to only Thesis or Dissertation
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Effects of Discharge Tube Geometry on Plasma Ion Oscillations

Description: This study considers the effect, on plasma ion oscillations, of various lengths of discharge tubes as well as various cross sections of discharge tubes. Four different gases were used in generating the plasma. Gas pressure and discharge voltage and current were varied to obtain a large number of signals. A historical survey is given to familiarize the reader with the field. The experimental equipment and procedure used in obtaining data is given. An analysis of the data obtained is presented al… more
Date: May 1975
Creator: Simmons, David Warren
Item Type: Refine your search to only Thesis or Dissertation
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A Classical Theory of the Dielectric Susceptibility of Anharmonic Crystals

Description: An expression for the dielectric susceptibility tensor of a cubic ionic crystal has been derived using the classical Liouville operator. The effect of cubic anharmonic forces is included as a perturbation on the harmonic crystal solution, and a series expansion for the dielectric susceptibility is developed. The most important terms in the series are identified and summed, yielding an expression for the complex susceptibility with an anharmonic contribution which is linearly dependent on temper… more
Date: May 1976
Creator: Kennedy, Howard V.
Item Type: Refine your search to only Thesis or Dissertation
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Theoretical Cross Section for Light Scattering from Superfluid Helium-4

Description: The finite lifetime of the bound roton pair is included in the theoretical light scattering cross section to explain the shape of the peak in the observed Raman light scattering cross section in He II. A model Hamiltonian is used to describe interactions between quasiparticles for the helium system. The equation of motion for the bound roton pair state, which is taken to be a collective mode of quasiparticle pairs, is solved. The cross section for light scattering is then derived using Fermi's … more
Date: May 1976
Creator: Latham, W. Peters, Jr., 1948-2016.
Item Type: Refine your search to only Thesis or Dissertation
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Measurement of the Rate Coefficients for the Bimolecular and Termolecular Charge Transfer Reactions of He₂⁺ with Ne, Ar, N₂, CO, CO₂, and CH₄

Description: The problem with which this investigation is concerned is that of measuring the rate coefficients for termolecular charge transfer reactions of He2+ in atmospheric pressure afterglows with the minority reacting species. Of particular interest was the discovery that the presence of a third body can change an improbable charge transfer reaction involving He+2 into a very probable one, as in the case of the reaction with argon. For example, in Tables II and II it was shown that less than a 300 tor… more
Date: May 1977
Creator: Lee, Francis Wha-Pyo
Item Type: Refine your search to only Thesis or Dissertation
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A Study of L-Shell X-Ray Production Cross Sections Due to [Hydrogen-1], [Helium-4], and [Lithium-7] Ion Bombardment of Selected Thin Rare Earth and ₈₂Pb Targets

Description: Thin target L-Shell x-ray production cross sections for protons incident on ₆₂Sm and ₇₀Yb in the energy range of 0.3 to 2.4 MeV/amu, alpha particles incident on ₆₂Sm, ₇₀Yb, and ₈₂Pb in the energy range of 0.15 to 4.8 MeV/amu, and lithium ions incident on ₅₈Ce, ₆₀Nd, ₆₂Sm, ₆₆Dy, ₆₇Ho, ₇₀Yb, and ₈₂Pb in the energy range of 0.8 to 4.4 MeV/amu have been measured. The cross section data have been compared to the planewave Born approximation (PWBA) and the PWBA modified to include binding energy and … more
Date: May 1978
Creator: Light, Glenn Michael
Item Type: Refine your search to only Thesis or Dissertation
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Microwave Properties of Hyaluronate Solutions Using a Resonant Microwave Cavity as a Probe

Description: Physiological functions of a biomacromolecule seem to be closely related to its molecular conformations. The knowledge of any conformational changes due to changes in its environment may lead to a proper understanding of its functions. Hyaluronic acid, a biomacromolecule with unusually high molecular weight and some important biological functions is the subject of the present work. A temperature-dependent transition in hyaluronate solution of 120 mg/ml concentration was observed at physiologica… more
Date: May 1980
Creator: Jani, Shirish K.
Item Type: Refine your search to only Thesis or Dissertation
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Low-Velocity K-Shell Ionization Cross Sections for Protons, Deuterons and Alpha Particles Bombarding Thin Metal Targets

Description: The purpose of this work was to examine the effect of the use the assumption κω2K/ΕCM «1 in calculating K-shell ionization cross sections in the plane wave Born approximation (PWBA) where κω2K is the observed binding energy of the K-shell and ECM is the energy of the incident particle in the center of mass system. Avoiding this assumption produces a threshold for ionization at Ecm = κω2K. Calculations employing the assumption, which leads to the use of approximate limits of integration, do not … more
Date: May 1981
Creator: Rice, Roger Karl
Item Type: Refine your search to only Thesis or Dissertation
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