# UNT Libraries - 129 Matching Results

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- Absolute Beta Counting Using Thick Sources
- The problem with which we shall concern ourselves in this paper is the self-scattering and self-absorption of beta particles by the source.
- Analyzing Magnet System for the Electrostatic Accelerator
- 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.
- The Angular Distribution and Total Flux of Neutrons Obtained from the Deuterium-Tritium Reaction
- Mono-energetic neutrons have been produced with the low-voltage Cockroft-Walton accelerator at North Texas State College using two different reactions. It is the purpose of this paper to report the angular distribution and total flux of the neutrons obtained from the T(D,n) reaction.
- The Angular Distribution of the Deuterium-Deuterium Neutrons with 100 Kev Deuterons
- It is the purpose of this paper to present the experimental techniques used in obtaining. 3.25 MeV neutrons from the H2(d,n)He3 reaction, as well as an analysis of the experimental data.
- Antiferromagnetic Ordering in Picryl-Amino-Carbazyl
- 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.
- Application of the Finite Element Method to Some Simple Systems in One and Two Dimensions.
- The finite element method (FEM) is reviewed and applied to the one-dimensional eigensystems of the isotropic harmonic oscillator, finite well, infinite well and radial hydrogen atom, and the two-dimensional eigensystems of the isotropic harmonic oscillator and the propagational modes of sound in a rectangular cavity. Computer codes that I developed were introduced and utilized to find accurate results for the FEM eigensolutions. One of the computer codes was modified and applied to the one-dimensional unbound quantum mechanical system of a square barrier potential and also provided accurate results.
- Application of the Wigner Formalism to a Slightly Relativistic Quantum Plasma
- A slightly relativistic fermion gas is described by the dynamical theory obtained from the Wigner distribution function. The problem is approached in a self-consistent manner including the two-body Darwin Hamiltonian. The goal is to find the departures from equilibrium and dispersion relations for wave propagation in the gas.
- Approach to Quantum Information starting from Bell's Inequality (Part I) and Statistical Analysis of Time Series Corresponding to Complex Processes (Part II)
- I: Quantum information obeys laws that subtly extend those governing classical information, making possible novel effect such as cryptography and quantum computation. Quantum computations are extremely sensitive to disruption by interaction of the computer with its environment, but this problem can be overcome by recently developed quantum versions of classical error-correcting codes and fault-tolerant circuits. Based on these ideas, the purpose of this paper is to provide an approach to quantum information by analyzing and demonstrating Bell's inequality and by discussing the problems related to decoherence and error-correcting. II: The growing need for a better understanding of complex processes has stimulated the development of new and more advanced data analysis techniques. The purpose of this research was to investigate some of the already existing techniques (Hurst's rescaled range and relative dispersion analysis), to develop a software able to process time series with these techniques, and to get familiar with the theory of diffusion processes.
- 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.
- Backscattering from Prolate Spheroids at Microwave Frequencies
- This thesis examines backscattering from prolate spheroids at microwave frequencies.
- Ballistic Deposition: Global Scaling and Local Time Series.
- Complexity can emerge from extremely simple rules. A paradigmatic example of this is the model of ballistic deposition (BD), a simple model of sedimentary rock growth. In two separate Problem-in-Lieu-of Thesis studies, BD was investigated numerically in (1+1)-D on a lattice. Both studies are combined in this document. For problem I, the global interface roughening (IR) process was studied in terms of effective scaling exponents for a generalized BD model. The model used incorporates a tunable parameter B to change the cooperation between aggregating particles. Scaling was found to depart increasingly from the predictions of Kardar-Parisi-Zhang theory both with decreasing system sizes and with increasing cooperation. For problem II, the local single column evolution during BD rock growth was studied via statistical analysis of time series. Connections were found between single column time series properties and the global IR process.
- Boundary Scattering of Electrons in Thin Cadmium Single Crystals
- In the present investigation, zinc was plated onto a cadmium crystal to determine the effect on the scattering parameter.
- Brownian Movement and Quantum Computers
- This problem in lieu of thesis is a discussion of two topics: Brownian movement and quantum computers. Brownian movement is a physical phenomenon in which the particle velocity is constantly undergoing random fluctuations. Chapters 2, 3 and 4, describe Brownian motion from three different perspectives. The next four chapters are devoted to the subject of quantum computers, which are the signal of a new era of technology and science combined together. In the first chapter I present to a reader the two topics of my problem in lieu of thesis. In the second chapter I explain the idea of Brownian motion, its interpretation as a stochastic process and I find its distribution function. The next chapter illustrates the probabilistic picture of Brownian motion, where the statistical averages over trajectories are related to the probability distribution function. Chapter 4 shows how to derive the Langevin equation, introduced in chapter 1, using a Hamiltonian picture of a bath with infinite number of harmonic oscillators. The chapter 5 explains how the idea of quantum computers was developed and how step-by-step all the puzzles for the field of quantum computers were created. The next chapter, chapter 6, discus the basic quantum unit of information namely, the so called qubit and its properties. Chapter 7 is devoted to quantum logic gates, which are important for conducting logic operation in quantum computers. This chapter explains how they were developed and how they are different from classical ones. Chapter 8 is about the quantum algorithm, Shor's algorithm. Quantum algorithm in quantum computers enables one to solve problems that are hard to solve on digital computers. The last chapter contains conclusions on Brownian movement and the field of quantum computers.
- A Calculation of the Kaon-Neutron Scattering Cross Section
- 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.
- 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.
- Chlorine Nuclear Quadrupole Resonance Absorption of 3, 4, 5, 6 - Tetrachlorophthalimide and 1, 3, 6, 8 - Tetrachloropyrene
- In this study frequency modulation was used with a regenerative spectrometer and a super-regenerative spectrometer to detect the nuclear quadrupole resonance frequencies of chlorine in two commercially available compounds, 1, 3, 6, 8 - tetrachlorophyrene and 3, 4, 5, 6 - tetrachlorophthalimide.
- 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 â€” 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.
- A Computer Analysis of Complex Gamma-Ray Spectra
- The purpose of this investigation was to provide a method for determining the relative intensities of all gamma rays in a particular spectrum, and thereby determine the relative transition probabilities.
- A Continuously Sensitive Cloud Chamber
- A continuous cloud chamber would be a valuable asset to laboratory work in nuclear and atomic physics. For this reason the construction and investigation of a continuously sensitive diffusion cloud chamber has been undertaken. It is the purpose of this paper to report the design and operating characteristics of such a chamber.
- A Correction Factor for the First Born Approximation
- This thesis looks at a Schroedinger equation and the Born approximation.
- Cross-Section at 15.6 and 16.1 MeV
- 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.
- Cross Section for the 165/Ho (n, 2n) 164/Ho Reaction at 15.6 MeV
- It was the purpose of this investigation to bring together the ideas and procedures involved in the measurement of (n, 2n) reaction cross sections. Some of the inherent properties of the material under investigation (Holium) are involved in determining these relationships.
- 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.
- Crystalline Polymorphism of Nitrates
- The purpose of this study was to investigate the polymorphism of a group of related compounds. Special emphasis was placed upon the temperature at which transitions occurred and a possible correlation of these temperatures with other properties of the compounds.
- D-D and D-T Neutron Excitation of Energy Levels in Cs133
- The purpose of this experiment was to make positive assignment of the Cs133 energy levels excited by the inelastic scattering of neutrons.
- 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.
- Design and Construction of a Positive Radio-Frequency Ion Source for the Production of Negative Ions
- It is the purpose of this paper to present a detailed account of the design and construction of this positive-ion source and associated equipment.
- Design and Testing of a Coincidence System
- This paper is concerned with the design, testing and performance of a coincidence system, the proposed North Texas State College accelerator.
- Design and Testing of a Corona Column and a Closed Gas Distribution System for a Tandem Van de Graaff Voltage Generator
- 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.
- Design and Testing of a Positive Ion Accelerator and Necessary Vacuum System
- This thesis is a study of the design and testing of a positive ion accelerator and necessary vacuum system.
- A Determination of the Bothe Depression Factor for Discs in Water
- The purpose of this work is to determine experimentally the depression of the neutron density by a detecting foil. The depression factor is known as the "self-shading" of the foil.
- A Deuterium-Deuterium Type Neutron Source
- In view of the advantages of its type, the decision to construct a neutron source of the particle accelerator type was made. The purpose of this thesis is to survey the problems encountered in the construction of the source.
- The Dielectric Constant of Galvinoxyl
- 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 100Â°K-420Â°K temperature range whether or not the organic free radical galvinoxyl and its diamagnetic parent molecule, dihydroxydiphenylmethane, undergo any such transitions.
- Dipole Moments of Diphenyl Compounds with Conjugated Double Bonds
- This thesis is a continuation of a study of molecular moments begun by Joseph T. Fielder. In his paper he discussed the theory and the equipment necessary for such a study. It is the purpose of this paper to set forth modifications of his equipment, to present data obtained with this modified equipment, and to interpret this data.
- Dipole Moments of Olefenic Diesters
- It is the purpose of this paper to present experimental data for the determination of the dielectric constant and the dipole moments for a series of olefenic diesters of the cis and trans configurations.
- Dipole Moments of Olefinic Esters
- It is the purpose of this thesis to investigate the applicability of the Debye equation to measurements dipole moments of polar compounds in dilute solutions of non-polar solvents more fully than has been done by previous workers at this institution.
- The Diurnal Variation of Cosmic Radiation
- The primary purpose of this investigation was to study the diurnal variation of cosmic-ray intensity.
- Dynamic Screening via Intense Laser Radiation and Its Effects on Bulk and Surface Plasma Dispersion Relations
- Recent experimentation with excitation of surface plasmons on a gold film in the Kretschmann configuration have shown what appears to be a superconductive effect. Researchers claimed to see the existence of electron pairing during scattering as well as magnetic field repulsion while twisting the polarization of the laser. In an attempt to explain this, they pointed to a combination of electron-electron scattering in external fields as well as dynamic screening via intense laser radiation. This paper expands upon the latter, taking a look at the properties of a dynamic polarization function, its effects on bulk and surface plasmon dispersion relations, and its various consequences.
- Dynamical Friction Coefficients for Plasmas Exhibiting Non-Spherical Electron Velocity Distributions
- 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.
- Effect of Sample Geometry on Magnetomorphic Oscillations in the Hall Effect in Cadium at Liquid-Helium Temperatures
- 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.
- 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.
- 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.
- 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.
- Electron Spin Resonance Absorption in Benzophenone Phenylhydrazone Negative Ion
- This thesis reports an electron spin resonance absorption study of the hyperfine interaction between nuclei and a single "nearly-free" electron in dilute solutions of the benzophenone phenylhydrazone free radical in tetrahydrofuran.
- Electron Transport in Bismuth at Liquid Helium Tempratures
- To obtain information on the band structure of bismuth, galvanomagnetic potentials were measured in a single crystal at liquid-helium and liquid-nitrogen temperatures. These measurements were analyzed for information on the different carriers, particularly for the existence of a high-mobility band of holes.
- Energy Losses of Protons Projected through a Plasma Due to Collisions with Electrons of the Plasma for a Variety of Non-Maxwellian Electron Velocity Distributions
- The purpose of this thesis is to study energy losses suffered by protons in traversing a plasma through collision with the electrons of the plasma. For these electrons a variety of non-Maxwellian velocity distributions are assumed.
- Experimental Determination of the Scattering Cross-section of Ogives and Prolate Spheroids at Microwave Frequencies
- Because of the great difficulty of obtaining exact numerical values of cross-section, and because of the inherent uncertainties in interpreting and evaluating the approximate methods, accurate experimental cross-section data would be extremely useful to the radar engineer. It was with this purpose in mind that the present long-range research program in microwave scattering was undertaken. Of immediate interest were the scattering properties of the prolate spheroid, the ogive (formed by rotating the minor segment of a circle around the chord), and, for comparison, the long cylinder.
- Extinguishment of a Low-pressure Argon Discharge by a Magnetic Field
- The experiment in this study involves the extinguishment of a low-pressure argon discharge by a magnetic field.
- Foil Depression Factors for Disc-shaped Detectors
- The generalized data which are presented in this thesis are the culmination of the determination of the foil depression factor using oblate spheroidal coordinates.
- Galvanomagnetic Determination of Energy Bands in Arsenic
- A study of the transport properties of a substance requires the determination of a set of transport coefficients by experiment. From these coefficients, the elements of the electrical conductivity tensor, thermoelectric tensor, et cetera can be determined. In this experiment, measurements and analyses of galvanomagnetic effects in a single crystal of arsenic were performed. The measurements were made at liquid-helium temperatures in magnetic fields ranging to 25 kilogauss. The gross isothermal, electrical conductivities have been analyzed to determine various parameters characterizing the energy bands in arsenic.