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Automatic Frequency Control of Microwave Radiation Sources (open access)

Automatic Frequency Control of Microwave Radiation Sources

Resonant cavity controlled klystron frequency stabilization circuits and quartz-crystal oscillator frequency stabilization circuits were investigated for reflex klystrons operating at frequencies in the X-band range. The crystal oscillator circuit employed achieved better than 2 parts in 10 in frequency stability. A test of the functional properties of the frequency standard was made using the Stark effect in molecules.
Date: August 1979
Creator: Payne, Bobby D.
System: The UNT Digital Library
The Classical Limit of Quantum Mechanics (open access)

The Classical Limit of Quantum Mechanics

The Feynman path integral formulation of quantum mechanics is a path integral representation for a propagator or probability amplitude in going between two points in space-time. The wave function is expressed in terms of an integral equation from which the Schrodinger equation can be derived. On taking the limit h — 0, the method of stationary phase can be applied and Newton's second law of motion is obtained. Also, the condition the phase vanishes leads to the Hamilton - Jacobi equation. The secondary objective of this paper is to study ways of relating quantum mechanics and classical mechanics. The Ehrenfest theorem is applied to a particle in an electromagnetic field. Expressions are found which are the hermitian Lorentz force operator, the hermitian torque operator, and the hermitian power operator.
Date: December 1977
Creator: Hefley, Velton Wade
System: The UNT Digital Library
Effects of Discharge Tube Geometry on Plasma Ion Oscillations (open access)

Effects of Discharge Tube Geometry on Plasma Ion Oscillations

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 along with possible explanations for the observed phenomena. Suggestions for future study are made.
Date: May 1975
Creator: Simmons, David Warren
System: The UNT Digital Library
Microwave Line Widths of the Asymmetric Top Formic Acid Molecule (open access)

Microwave Line Widths of the Asymmetric Top Formic Acid Molecule

This work consisted of an experimental investigation of the formic acid (HCOOH) molecule's rotational spectrum. Measurements of line widths were obtained for J = 5, 12, 13, 19, and 20 for a pressure range from 1 to 10 microns. A linear behavior between Av and p was observed as predicted by theory. The line width parameter Avp was observed to depend on the quantum number J. Hard sphere collision diameters b1 were calculated using the obtained AvP values. These deduced hard sphere values were found to be larger than the physical size of the molecule. This result was found to be in general agreement with other investigation in which long range forces (dipole-dipole) dominate.
Date: August 1974
Creator: Maynard, Wayne R.
System: The UNT Digital Library
Relaxation Time Measurements for Collision Processes in the Surface Layers of Conductors and Semiconductors Near 10 Ghz (open access)

Relaxation Time Measurements for Collision Processes in the Surface Layers of Conductors and Semiconductors Near 10 Ghz

This thesis represents one phase of a joint effort of research on the properties of liquids and solids. This work is concerned primarily with the microwave properties of solids. In this investigation the properties exhibited by conductor and semiconductor materials when they are subjected to electromagnetic radiation of microwave frequency are studied. The method utilized in this experiment is the perturbation of a resonant cavity produced by introduction of a cylindrically shaped sample into it.
Date: December 1973
Creator: Childress, Larry Wayne
System: The UNT Digital Library
Electrical Conductivity in Thin Films (open access)

Electrical Conductivity in Thin Films

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
System: The UNT Digital Library
A Decay Scheme for 164 Ho (open access)

A Decay Scheme for 164 Ho

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.
Date: December 1972
Creator: Guertin, James
System: The UNT Digital Library
Pressure Dependence of Line Widths of Microwave Spectra of Sulphur Dioxide (open access)

Pressure Dependence of Line Widths of Microwave Spectra of Sulphur Dioxide

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.
Date: December 1972
Creator: Yang, Wei Han
System: The UNT Digital Library
Quantized Hydrodynamics (open access)

Quantized Hydrodynamics

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.
Date: August 1972
Creator: Coomer, Grant C.
System: The UNT Digital Library
Virial Theorem for a Molecule (open access)

Virial Theorem for a Molecule

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.
System: The UNT Digital Library
Cross Section Measurements in Praseodymium-141 as a Function of Neutron Bombarding Energy (open access)

Cross Section Measurements in Praseodymium-141 as a Function of Neutron Bombarding Energy

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
System: The UNT Digital Library
Phase Shift Determination for Elastic Potential Scattering, Using the IBM 360-50 Computer (open access)

Phase Shift Determination for Elastic Potential Scattering, Using the IBM 360-50 Computer

The primary objective of this paper is to present a computerized method for the extraction of phase shifts from an angular distribution. This was accomplished using a least squares curve fitting routine.
Date: May 1971
Creator: Psencik, James A.
System: The UNT Digital Library
Carbon Contamination Measurements in Single Silicon Crystals (open access)

Carbon Contamination Measurements in Single Silicon Crystals

The intent of this investigation was to directly measure the amount of carbon contamination in a single silicon crystal and, in so doing, develop a mathematical procedure that would be applicable to other contaminants in other substances.
Date: December 1970
Creator: Logsdon, Lawrence E.
System: The UNT Digital Library
Nuclear Reactions on the Palladium Isotopes (open access)

Nuclear Reactions on the Palladium Isotopes

The problem of interest in this investigation was to determine the cross sections of five nuclear reactions which occur when irradiating natural palladium with neutrons which have energy values of 15.1, 15.9, and 16.3 MeV. The cross sections were measured relative to a copper monitor which was "sandwitched" in with the palladium target.
Date: December 1970
Creator: White, Ronald Lee
System: The UNT Digital Library
A Study of the Decay Levels of 169/Tm69 (open access)

A Study of the Decay Levels of 169/Tm69

The purpose of this investigation was to study the radiations of the 169/Tm nucleus as it de-excites after the electron capture decay of the 169/Yb. Numerous unreported gammas were present in the sample. The origins of these gamma rays were found.
Date: December 1970
Creator: Harris, Robert J.
System: The UNT Digital Library
The Effects of Lead Placement and Sample Shape in the Measurement of Electrical Resistivity (open access)

The Effects of Lead Placement and Sample Shape in the Measurement of Electrical Resistivity

This thesis is a study of the effects of lead placement and sample shape in the measurement of electrical resistivity.
Date: August 1970
Creator: Stephens, Anthony E.
System: The UNT Digital Library
Measurement of the Atomic-oxygen Concentration under Simulated Upper Atmosphere Conditions (open access)

Measurement of the Atomic-oxygen Concentration under Simulated Upper Atmosphere Conditions

This thesis describes an experimental technique for measuring the atomic-oxygen concentration under simulated upper atmosphere conditions.
Date: January 1970
Creator: Grable, Weliko C.
System: The UNT Digital Library
A Precision Angular Correlation Table and Calculation of Geometrical Correction Factors (open access)

A Precision Angular Correlation Table and Calculation of Geometrical Correction Factors

In recent years y-y angular correlations have been very useful in confirming the spins of excited nuclear states. Angular correlation techniques have also been employed to study the electric and magnetic character of excited nuclear states. With these things in mind, it was decided to design, construct, and test a precision angular correlation table.
Date: January 1970
Creator: Rowton, Larry James
System: The UNT Digital Library