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  Partner: UNT Libraries
 Degree Discipline: Physics
 Collection: UNT Theses and Dissertations
A Calculation of the Kaon-Neutron Scattering Cross Section

A Calculation of the Kaon-Neutron Scattering Cross Section

Date: June 1966
Creator: Hooper, Robert Gibson
Description: The purpose of this investigation was to study the scattering processes of K+ mesons with neutrons. In order to do such a study one must first make certain basic assumptions about the type of interaction involved and then proceed to calculate physically meaningful qualities which describe the processes. Thus, the problem is this: assuming the validity of Feynman's rules for these strongly interacting particles, calculate the differential and total scattering cross sections for the interaction of scalar K+ mesons and neutrons.
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Analyzing Magnet System for the Electrostatic Accelerator

Analyzing Magnet System for the Electrostatic Accelerator

Date: August 1954
Creator: Young, Thomas E.
Description: This thesis describes the design and construction of a linear accelerator, specifically, a positive-ion source, a high voltage supply, an accelerating column, and the necessary associated vacuum system.
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Stochastic Mechanical Systems

Stochastic Mechanical Systems

Date: August 1960
Creator: Bost, Robert Berton
Description: To understand the phenomena associated with such stochastic processes and to predict, at least qualitatively, the behavior of mechanical systems within environments which are completely random in time, new mechanical tools are necessary. Fortunately, the derivation of these tools does not necessitate a complete departure from existing theories. In fact, they may be considered as an extension of the well-defined theory of the integral transform, in particular, the exponential Fourier integral transform.
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Dynamical Friction Coefficients for Plasmas Exhibiting Non-Spherical Electron Velocity Distributions

Dynamical Friction Coefficients for Plasmas Exhibiting Non-Spherical Electron Velocity Distributions

Date: August 1961
Creator: Williams, G. Bruce
Description: This investigation is designed to find the net rate of decrease in the component of velocity parallel to the original direction of motion of a proton moving through an electron gas exhibiting a non-spherical velocity distribution.
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D-D and D-T Neutron Excitation of Energy Levels in Cs133

D-D and D-T Neutron Excitation of Energy Levels in Cs133

Date: January 1961
Creator: Dawson, Horace Ray
Description: The purpose of this experiment was to make positive assignment of the Cs133 energy levels excited by the inelastic scattering of neutrons.
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A Study of Emitter Drift in Transistors

A Study of Emitter Drift in Transistors

Date: August 1961
Creator: Malone, Farris Douglas
Description: The purpose of this investigation was to determine the parameters of emitter drift and to suggest a mechanism for this phenomenon.
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Temperature Dependence of the Magnetic Susceptibility of the Organic Free Radical Galvinoxyl

Temperature Dependence of the Magnetic Susceptibility of the Organic Free Radical Galvinoxyl

Date: August 1965
Creator: Morphew, Sam W.
Description: This thesis examines temperature dependence of magnetic susceptibility of the organic free radical galvinoxyl.
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Design and Testing of a Corona Column and a Closed Gas Distribution System for a Tandem Van de Graaff Voltage Generator

Design and Testing of a Corona Column and a Closed Gas Distribution System for a Tandem Van de Graaff Voltage Generator

Date: June 1962
Creator: Gray, Thomas Jack
Description: The purpose of this study had been to design and test a corona column and an insulating gas distribution system for a small tandem Van de Graaff. The intent of this paper is to describe the gas handling system and to compare experimentally the effects of corona electrode shape on the corona current carried between adjacent sections of the column.
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A Microwave Spectrometer for Narrow-line Electron Spin Resonance Studies

A Microwave Spectrometer for Narrow-line Electron Spin Resonance Studies

Date: January 1966
Creator: Neie, Van ElRoy
Description: This thesis explores the basic theory, design and construction of electron spin resonance spectrometer.
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A Vacuum Tube for an Electrostatic Generator

A Vacuum Tube for an Electrostatic Generator

Date: August 1966
Creator: Pool, John Reginald
Description: The purpose of this study has been to construct two accelerating tubes with small beam apertures for the Van de Graaff, modifying the prototype tube designed and tested by Wiley (20), to design and construct a vacuum system for evacuating the tubes, and to determine the characteristics of the tube under operating conditions while installed in the generator.
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The Diurnal Variation of Cosmic Radiation

The Diurnal Variation of Cosmic Radiation

Date: August 1965
Creator: Fowler, Brooks C.
Description: The primary purpose of this investigation was to study the diurnal variation of cosmic-ray intensity.
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Nuclear Magnetic Resonance in a Crystalline Stable Free Radical--Wurster's Blue Perchlorate

Nuclear Magnetic Resonance in a Crystalline Stable Free Radical--Wurster's Blue Perchlorate

Date: August 1965
Creator: McCann, Thomas E.
Description: This thesis investigates the nuclear magnetic resonance in a crystalline stable free radical.
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Design and Testing of a Positive Ion Accelerator and Necessary Vacuum System

Design and Testing of a Positive Ion Accelerator and Necessary Vacuum System

Date: August 1953
Creator: McKay, Vern A.
Description: This thesis is a study of the design and testing of a positive ion accelerator and necessary vacuum system.
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Antiferromagnetic Ordering in Picryl-Amino-Carbazyl

Antiferromagnetic Ordering in Picryl-Amino-Carbazyl

Date: August 1964
Creator: Porter, Wilbur A.
Description: The purpose of the experiment was to investigate other paramagnetic salts to determine whether the W. B. perchlorate type peak was more common than previously suspected. An organic salt, picryl-n-amino-carbazyl, was chosen.
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The Optimum Design of a Broad-band Helix for Use in Electron Spin Resonance

The Optimum Design of a Broad-band Helix for Use in Electron Spin Resonance

Date: June 1967
Creator: Garlow, John R.
Description: This thesis examines optimum designs for broad-band helix to be used in electron spin resonance.
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Electrical Conductivity in Thin Films

Electrical Conductivity in Thin Films

Date: May 1973
Creator: Meyer, Frederick Otto
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.
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Effect of Sample Geometry on Magnetomorphic Oscillations in the Hall Effect in Cadium at Liquid-Helium Temperatures

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

Date: June 1967
Creator: Fielder, James Thomas
Description: 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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The Effects of Cesium Deposition and Gas Exposure on the Field Emission Properties of Single Wall and Multiwall Carbon Nanotubes

The Effects of Cesium Deposition and Gas Exposure on the Field Emission Properties of Single Wall and Multiwall Carbon Nanotubes

Date: May 2002
Creator: Wadhawan, Atul
Description: The effects of Cs deposition on the field emission (FE) properties of single-walled carbon nanotube (SWNT) bundles were studied. In addition, a comparative study was made on the effects of O2, Ar and H2 gases on the field emission properties of SWNT bundles and multiwall carbon nanotubes (MWNTs). We observed that Cs deposition decreases the turn-on field for FE by a factor of 2.1 - 2.9 and increases the FE current by 6 orders of magnitude. After Cs deposition, the FE current versus voltage (I-V) curves showed non-Fowler-Nordheim behavior at large currents consistent with tunneling from adsorbate states. At lower currents, the ratio of the slope of the FE I-V curves before and after Cs deposition was approximately 2.1. Exposure to N2 does not decrease the FE current, while exposure to O2 decreases the FE current. Our results show that cesiated SWNT bundles have great potential as economical and reliable vacuum electron sources. We find that H2 and Ar gases do not significantly affect the FE properties of SWNTs or MWNTs. O2 temporarily reduces the FE current and increases the turn-on voltage of SWNTs. Full recovery of these properties occurred after operation in UHV. The higher operating voltages in an ...
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The Effect of Average Grain Size on Polycrystalline Diamond Films

The Effect of Average Grain Size on Polycrystalline Diamond Films

Date: May 2002
Creator: Abbott, Patrick Roland
Description: The work function of hydrogen-terminated, polycrystalline diamond was studied using ultraviolet photoelectron spectroscopy. Polycrystalline diamond films were deposited onto molybdenum substrates by electrophoresis for grain sizes ranging from 0.3 to 108 microns. The work function and electron affinity were measured using 21.2 eV photons from a helium plasma source. The films were characterized by x-ray photoelectron spectroscopy to determine elemental composition and the sp2/sp3 carbon fraction. The percentage of (111) diamond was determined by x-ray diffraction, and scanning electron microscopy was performed to determine average grain size. The measured work function has a maximum of 5.1 eV at 0.3 microns, and decreases to 3.2 eV at approximately 4 microns. Then the work function increases with increasing grain size to 4.0 eV at 15 microns and then asymptotically approaches the 4.8 eV work function of single crystal diamond at 108 microns. These results are consistent with a 3-component model in which the work function is controlled by single-crystal (111) diamond at larger grain sizes, graphitic carbon at smaller grain sizes, and by the electron affinity for the intervening grain sizes.
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A Determination of the Fine Structure Constant Using Precision Measurements of Helium Fine Structure

A Determination of the Fine Structure Constant Using Precision Measurements of Helium Fine Structure

Date: August 2010
Creator: Smiciklas, Marc
Description: Spectroscopic measurements of the helium atom are performed to high precision using an atomic beam apparatus and electro-optic laser techniques. These measurements, in addition to serving as a test of helium theory, also provide a new determination of the fine structure constant α. An apparatus was designed and built to overcome limitations encountered in a previous experiment. Not only did this allow an improved level of precision but also enabled new consistency checks, including an extremely useful measurement in 3He. I discuss the details of the experimental setup along with the major changes and improvements. A new value for the J = 0 to 2 fine structure interval in the 23P state of 4He is measured to be 31 908 131.25(30) kHz. The 300 Hz precision of this result represents an improvement over previous results by more than a factor of three. Combined with the latest theoretical calculations, this yields a new determination of α with better than 5 ppb uncertainty, α-1 = 137.035 999 55(64).
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Quantized Hydrodynamics

Quantized Hydrodynamics

Date: August 1972
Creator: Coomer, Grant C.
Description: The object of this paper is to derive Landau's theory of quantized hydrodynamics from the many-particle Schroedinger equation. Landau's results are obtained, together with an additional term in the Hamiltonian.
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Pressure Dependence of Line Widths of Microwave Spectra of Sulphur Dioxide

Pressure Dependence of Line Widths of Microwave Spectra of Sulphur Dioxide

Date: December 1972
Creator: Yang, Wei Han
Description: Measurements of line width parameters for eleven rotational transitions of type (J -- J + 1) of SO2 were made and are reported herein. The line width quantum number (J) trend was obtained. The microwave spectrograph used for these measurements of line width is described. Operational methods to operate the spectrograph are presented and discussed, with particular attention given to how to measure the line width. Suggestions for future avenues of probing this molecule to ascertain the non-uniform behavior of the line width parameter over the quantum number and frequency range are given.
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A Decay Scheme for 164 Ho

A Decay Scheme for 164 Ho

Date: December 1972
Creator: Guertin, James
Description: The present investigation was prompted by several considerations. In previous studies there was considerable variance with regard to the reported values for the half-lives of the isomeric and ground states in 164 Ho. There was also considerable variance with regard to the values reported for the branching ratios and the relative intensities of the transitions. Thus a further study of the problem was needed.
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Virial Theorem for a Molecule

Virial Theorem for a Molecule

Date: May 1972
Creator: Ranade, Manjula A.
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.
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