Physical Sciences and Mathematics Commons^™

Optical And Electron-Paramagnetic Resonance Studies Of Sodium-Fluoride, Ronald Allen Andrews

Wayne State University Dissertations

No abstract provided.

Geometrical Representations Of Relativistic Motion, Jeffrey H. Robbins

Physics & Astronomy ETDs

This investigation begins with the development of a transformation or mapping in velocity space of such a character that velocities are mapped into a quantity that adds linearly, while velocities add non-linearly according to the Einstein Law of Addition, and has no upper limit to its magnitude, i.e., when the speed of an object approaches that of light in a vacuum, this quantity becomes infinitely large. Kinematic relationships, in Newtonian form, for a particle undergoing acceleration, are developed in a frame of reference that remains attached to the particle using the new variable (W). It is found that relativistic energy …

Coulomb Excitation Of The Ytterbium Isotopes., John M. Palms

Physics & Astronomy ETDs

Coulomb excitation studies have been performed on the ytterbium isotopes 171, 172, 173, 174, and 176 using oxygen ions having energies up to 55 MeV. Resulting de-excitation gamma rays have been observed in particle coincidence with a NaI(Tl) detector and as single spectra with a Ge(Li) detector. The ground state rotational bands of the Yb171 and Yb173 isotopes have been excited to the 13/2- level. The 13/2- and 11/2-levels of both nuclei have not been reported before. In addition to the transitions from the ground state band, gamma rays were observed from Yb171 and Yb173 coming from other bands. A …

Investigation Of Propagation Of Light Through Gases And Air Structures Treated As Wave Guides., Richard W. Christiansen

Physics & Astronomy ETDs

The equations defining the propagation of electromagnetic radiation down cylindrical dielectric wave guides are developed. A Helium-Neon laser is used to illuminate several different cylindrical wave guides. The propagation nodes are recorded on photographic plates. Using the field equations, the electric field on a transverse plane is plotted and used to explain some HE_im modes observed. The patterns recorded on the photographic plates are described and discussed in terms of the propagation modes.

X-Ray Diffraction And Electron Microscopy Studies Of Glasses Containing Antimony, Sadek Momtaz Tadross

Archived Theses and Dissertations

No abstract provided.

Simultaneous Movement Of Water And Herbicides In Unsaturated Soils, Ming-Shyong Yang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Since weed killers were developed in the early part of the decade beginning in 1940, herbicides have been increasing in use until they are now widely used to control weeds. The application of herbicides has thus become a regular agricultural and ecological practice.

Simultaneous Flow Of Heat And Water In Plant Tissue, Gaylon Sanford Campbell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although biological phenomena may be partially described in a general way without the use of mathematics and physics, the experimental results may be more meaningful if they are analyzed on the basis of physical and mathematical laws. The complexity of biological systems has made the application to them of mathematics and physics rather difficult, and only recently has much progress been made. Although it has yet been possible to describe only a few simple biological systems by actual equations, a great deal of qualitative information may be obtained by applying physics and mathematics. Russell (1960, p. 439) said

In principle …

Design And Construction Of A Pulsed Glass Laser, Mostafa Ibrahim Azab

Archived Theses and Dissertations

No abstract provided.

The Electrical Resistivity Of Different Types Of Glasses, Fadel Youssef Iskandar Assabghy

Archived Theses and Dissertations

No abstract provided.

An Investigation Of The Control Of Hydraulic Fracturing Through The Inclusions Of Prefractures, William Joseph Kabeiseman

Doctoral Dissertations

"Among the methods for determining the in-situ state of stress within the earth’s crust, hydraulic fracturing has been and is receiving much attention. This method, in principle, measures stress directly with no delicate electronic equipment required nor knowledge of the elastic modulus of the material.

This dissertation investigates experimentally whether or not control of fracture orientation can be achieved by the introduction of circular and elliptical prefractures along with sand inclusions into cast hydrostone blocks which are hydraulically fractured. A mathematical model is presented and analytically solved for the stress condition associated with a circular crack containing fluid pressure with …

Charged Particle Fluxes In The South Atlantic Radiation Anomaly, Nicholas S. P. King

Physics & Astronomy ETDs

Data from a scintillator and two Cerenkov counters aboard the 0S0-B2 satellite are converted from counting rates to omnidirectional fluxes in the South Atlantic Radiation Anomaly. Isointensity contours are obtained for the anomaly with omnidirectional fluxes being of the order of 90 protons/cm2 -sec and 5 x 10 3 electrons/cm2 -sec. The South Atlantic Radiation Anomaly is postulated to include an electron dump into the earth's atmosphere due to the observed differences between the isointensity distributions for protons and electrons.

The Structure Of The Vibrational Relaxation Zone Of Shock Waves In Oxygen, Robert W. Lutz

Physics & Astronomy ETDs

The vibrational relaxation of pure oxygen has been studied in incident shock waves in the temperature range l000-3700° K. The re­laxation process was observed by measuring density gradients in the relaxation zone with the quantitative laser schlieren technique. The high sensitivity of this technique allowed determination of the relaxation time T, defined by the Bethe-Teller equation

= [ E - E ],

as a function of temperature and pressure in the relaxation zone. The variation in P the relaxation time at one atm, during th individual experiments, was found to agree with the over-all temperature dependence derived from the entire …

An Experimental Study Of The Back Scattering Of Coherent Light From Falling Water Drops., William Ogle

Physics & Astronomy ETDs

Introduction

The purpose of this study is to make a statistical investigation of the backscattering of light from freely falling water drops, and to determine if the surface wave is a significant contribution to the backscattered intensity from large drops.

An Experimental Study Of The Rate Of Evaporation Of Water Droplets., Pyung Syk Ro

Physics & Astronomy ETDs

The basic equation (Maxwell equation) for the evaporation rate of small droplets motionless relative to the ambient gas is verified by our experiment using an ultrasonic droplet suspension device. By using an ultrasonic device, a good approximation to the conditions of evaporation of free water droplets ranging from 0.4 mm to 2.0 mm in diameter is obtained.

Since it is expected that the back-scattering cross section of an incoherent light beam from a water drop is proportional to the square of the radius of the water drop, the possibility of measuring evaporation rates by using incoherent light is suggested. This …

Radiation Damage Studies Of Libyan Desert Silica Glass, Farkhonda Hassan

Archived Theses and Dissertations

No abstract provided.

Re-Evaporation Nuclei And Evaporation In A Wilson Cloud Chamber, James G. Smith

Doctoral Dissertations

"Experimental techniques are developed for observing droplet evaporation in the submicroscopic size range. An expansion-compression cloud chamber with an atmosphere of tank helium saturated with water vapor is employed. This work was undertaken with the aim of examining submicroscopic droplet behavior and the existence of re-evaporation nuclei, a form of memory effect.

The theories of evaporation and nucleation on submicroscopic drop residues were re-examined, and alterations which appear to be consistent with the results of this work were incorporated into the evaporation theory.

The observed continually decreasing evaporation rate with diminishing droplet size confirms the existence of re-evaporation nuclei, but …

Dynamics Of Disordered Harmonic Lattices, Daniel N. Payton Iii

Doctoral Dissertations

"Extensive numerical and analytic studies of vibrational spectra, normal modes, thermodynamic properties, and dynamical properties of harmonic systems with varying degrees of substitutional disorder have been made. The effects on observable properties of random mixtures of two or more species of atoms with differing masses and differing couplings to nearest-and next-nearest-neighbors have been investigated. Using the IBM-7030 digital computer, spectra for linear chains of 100,000 atoms have been obtained. Calculations in two and three dimensions have been limited to arrays of approximately 1000 atoms. Varying composition, mass ratio, and order affect the spectra in two and three dimensions in ways …

Calculated Cohesive Energy Of The Ordered Copper-Gold Alloy Cu Au I, Richard W. Hannum

Doctoral Dissertations

"The ordered alloy CuAu is the fifty atomic per cent alloy in the copper-gold system. It was observed by Johansson and Linde(1) and was one of the first ordered alloys to be studied by x-ray diffraction methods(Z, 3). Two ordered superlattices of CuAu are observed. CuAu I exists below 380° C and has a tetragonal structure which is a slight distortion of the face- centered cubic. It is very highly ordered, with all copper and all gold atoms in alternate (002) planes, as shown in Figure 2. CuAu II, which exists between 380° and 415° C, is orthorhombic in structure(4) …

Theory Of The Lunar Photoelectron Atmosphere, Hal Emerson Mccloud Jr.

Doctoral Dissertations

"By considering the mechanics of an electron projected into an arbitrary potential field together with Poisson's equation it is possible to set up a differential equation for the electrostatic potential. The equation may be integrated and the photoelectron density found as a function of height for four approximate models. A simple model based upon monoenergetic photons and monoenergetic electrons ejected vertically upward yields rough estimates of the parameters of interest. Another model takes into account the fact that the photoelectrons are ejected at all angles. A general model takes into account the illumination of the lunar surface by solar (black …

Diffusional Drop Growth In A Supersaturated Atmosphere, John C. Carstens

Doctoral Dissertations

"The effect which a growing droplet has on the supersaturated atmosphere surrounding it is analyzed by assuming a macroscopic diffusional growth mechanism involving both heat and vapor. The problem is solved, for cloud-chamber conditions, first for very short times assuming a fixed radius, and then for longer times assuming the establishment of "quasi" steady-state conditions. Knowledge of the way in which droplet growth affects supersaturation is important in the evaluation of nucleation rates"--Abstract, page ii.

Absolute Soft X-Ray Dosimetry For Radiation Chemistry Studies, Howard Sajon Joyner

Masters Theses

"A homogeneous, variable plate separation ion chamber consisting of a polyethylene body and employing flowing ethylene as the cavity gas has been designed and tested for the specification soft x-ray (<75kV) energy deposition in typical hydrocarbons. The variable plate separation feature provided primary data on the differential specific ionization originating within the cavity gas occupying the effective collector volume which is independent of inherent chamber inhomogeneities associated with the electrically conducting films comprizing the chamber electrodes. These data demonstrated that charged particle equilibrium is established within the first few ten thousandths of an inch in typical solid hydrocarbons irradiated with this class of sources. Comparison of this type of chamber with a fixed plate separation, static cavity gas mode of operation showed that the latter may predict dose rates with inherent errors exceeding 100%. With the quality of electronic readout accessories presently available, the variable plate separation chamber yielded dose rate data exhibiting a probable error of 3.8 percent (plus the unknown uncertainty in the literature data on the energy required to form an ion pair), and an ultimate limiting error of less than 2 percent appears feasible"--Abstract, page ii.

The Mössbauer Effect In Bismuth Ferrate, Bruce A. Banks

Masters Theses

"The magnetic hyperfine structure of the Fe⁵⁷ nuclei in bismuth ferrate was investigated using the Mössbauer effect. A Mössbauer effect spectrometer was built with consideration given to the elimination of vibration and the optimizing of the source, absorber, and detector geometries to produce the largest fractional Mössbauer effect per fractional standard deviation. The internal magnetic field at the Fe nuclei in BiFeO₃ was determined to (482 ± 9) kilooersteds at room temperature"--Abstract, page ii.

The Faraday Rotation And Dispersive Doppler Effects In The Ionosphere At Oblique Incidence, Charles Roland Baugher Ii

Masters Theses

"Integral equations for the isotropic and anisotropic ray path of a radio wave propagating through the ionosphere are developed. These equations assume a spherically stratisfied ionosphere and are equivalent to a detailed ray-tracing process. A method is devised to utilize these equations in the evaluation of combined Faraday rotation and dispersive Doppler data from earth satellites for subionospheric electron content. The method, which corrects for horizontal ionospheric gradients, is applied to data from the Explorer 22 satellite and some preliminary results are discussed"--Abstract, page ii.

The Construction Of A Multi-Threshold Foil For Fast Flux Measurements, Michael Henry Holkenbrink

Masters Theses

"The construction of a multi-threshold foil for fast neutron flux measurements is investigated. The factors governing the selection of the materials are the energy response of the given reactor, the half-life of the daughter, the prominent gamma ray emitted during decays, the power level of the reactor, the availability of adequate cross section data, and the alloying properties of the composite foil. A ternary system was chosen as a compromise between the difficulty of fabrication and the amount of information gained from one foil. The particular system chosen was In- P- Fe. The threshold reactions of these elements are In¹¹⁵ …

Changes In Minority Carrier Lifetime In Silicon And Gallium Arsenide Resulting From Irradiations With 22- And 40-Mev Protons, Marvin E. Beatty

Dissertations, Theses, and Masters Projects

No abstract provided.