Digital Commons Network^™

Linear Regression Models Of Sound Velocity In The North Atlantic Ocean Below A Critical Depth, Richard Roland Kunkel

Doctoral Dissertations

"Sound velocity models currently in use by the U. S. Navy require difficult data sampling at great expense. This study is to investigate the feasibility of a sound velocity model dependent only upon position that would be valid for a selected, reasonably large, near homogeneous area of the ocean. The most important position parameters are latitude, longitude, and depth. To accomplish this objective a critical depth of 2500 meters was established for an 8° by 20° rectangle of the Sargasso Sea which lies within the North Atlantic Ocean. The critical depth is defined as the depth at which the characteristics …

Diffusion And Internal Friction In Sodium-Rubidium Silicate Glasses, Gary L. Mcvay

Doctoral Dissertations

"The internal friction and self diffusion coefficients of sodium and rubidium ions for (1 - X) Na₂O·X Rb₂O·3 SiO₂ glasses have been measured. The diffusion measurements employed radioactive isotopes and a thin sectioning technique and extended from 350 to 500°C. Internal friction measurements were made from -150 to 500°C and at frequencies of 0.05 to 6000 Hz. The maximum height for the mixed alkali internal friction peak occurs at the composition where the sodium and rubidium diffusion coefficients are equal. It is concluded that the mechanism responsible for the mixed alkali peak is a cooperative rearrangement of sodium-rubidium ions and …

Synthesis Heuristics For Large Asynchronous Sequential Circuits, Robert Judson Smith

Doctoral Dissertations

"Many well-known synthesis procedures for asynchronous sequential circuits produce minimal or near-minimal results, but are practical only for very small problems. These algorithms become unwieldy when applied to "large" circuits with, for example, three or more input variables and twenty or more internal states. New heuristic procedures are described which permit the synthesis of very large machines. Although the resulting designs are generally not minimal, the heuristics are able to produce near-minimal solutions orders of magnitude more rapidly than the minimal algorithms. A method for specifying sequential circuit behavior is presented. Input-output sequences define submachines or modules. When properly interconnected, …

Optimizing Diesel Engine Efficiency Using The Controllability Of A Variable Ratio Hydrostatic Transmission, Gordon Wright

Doctoral Dissertations

"A linear mathematical model of a diesel engine, hydrostatic transmission, and electric dynamometer system was developed. This model was used as an aid in designing a single input controller which regulates engine speed to optimize efficiency while maintaining constant transmission output speed under changing load conditions. Compensation was necessary to stabilize the system because of positive feedback in the engine control system. The compensated system's response was compared to that which was predicted analytically. The analytical model was then extended to design the control system parameters to operate the engine and transmission in a representative vehicle"--Abstract, page ii.

Dialkylaniline N-Oxides Reactions Of Dialkylanilines With Chiral Peroxy Compounds, Karen Patti Long

Doctoral Dissertations

No abstract provided.

A Practical Comparison Of Atomic Fluorescence Flame Spectrometry With Atomic Absorption Flame Spectrometry, Michael Andrew Pleva

Doctoral Dissertations

No abstract provided.

Part I Asymmetric Reduction Of Ketones With The Grignard Reagent From R-1-Bromo-2-Phenylethane-1,1,2-Deuterium(3) Part Ii Electrophilicallyassisted Nucleophilic Opening Of Optically Active Styrene-Oxide, Joseph Edward Tomaszewski

Doctoral Dissertations

No abstract provided.

Psychological Thought Within The Context Of The Scientific Revolution, 1665-1700, Barbara Carr Ross

Doctoral Dissertations

No abstract provided.

Investigation Of Liquid Carryover In The Girdler-Sulfide Process For Production Of Heavy Water At The Aec Savannah River Plant, Samuel Clark Allen

Doctoral Dissertations

"An investigation of the causes of liquid carryover in the Girdler-Sulfide process for the production of heavy water was carried out using 12 samples of carbon collected over a one-year time period. Organic impurities from the feedwater were concentrated by adsorption on carbon. Studies of methods for the drying of carbon showed that freeze drying resulted in the minimum reproducible moisture retention without gross loss of the adsorbed organic materials. Rotary vacuum evaporation and air drying of beds of carbon were proven to be less efficient. A study was made of the variables which affect extraction efficiency by the Soxhlet …

Ionization Of Air Produced By Strong Shocks, Howard Sajon Joyner

Doctoral Dissertations

"This dissertation provides theoretical predictions along with experimental results for electron concentrations behind a shock as a function of Mach number over a range from 11 to 20 using a combustion driven shock tube operating in air. These theoretical predictions represent an upper bound for chemical equilibrium. The model for air was 78.0880% nitrogen, 20.949% oxygen, 0.0300% carbon dioxide, 0 .9300% argon, 0.0025%neon, and 0.0005% helium. Also the theory of a double diaphragm shock tube with corresponding pressure ratio vs. Mach number relationships is provided. A computor [sic] program using iterative techniques for a succinct presentation covering the modifications and …

Anodic Dissolution Of Zinc In Potassium Iodide-Potassium Iodate Solutions, Chi-Chiu Yao

Doctoral Dissertations

"The anodic dissolution of Zn was studied in KI-KIO₃ solutions at 25ºC. In I⁻ solutions, it was found that the apparent valence of Zn ions going into solution is approximately two. Smaller values are obtained in IO₃⁻ solutions, with the most pronounced changes occurring in the higher concentrations. An empirical equation is derived relating the apparent valence (or anode efficiency) to the current density and concentrations of IO₃⁻ and I⁻. An anodic dissolution mechanism is proposed"--Abstract, page 1.

Penetration In Granite By Shaped Charge Liners Of Various Metals, Hemendra Nath Kalia

Doctoral Dissertations

"The penetration in Missouri red granite by cylindrical charges with metal liners of aluminum 2011 (T-3), aluminum 7075 (T-6), yellow brass, monel, maraging steel (vascomax 250), and copper was measured. Metals having high ductility and moderate compressive strength penetrated deeper than high strength maraging steel. Aluminum required a greater standoff for optimum penetration than the other metal liners tested. Preliminary metallographic studies of the liner metals and slugs showed that the grains had elongated along the slug axis. The metals containing zinc formed very small or no slugs. The granite grains were highly fractured. The holes were discolored and coated …

Effect Of Axial Dispersion On Interphase Mass Transfer In Packed Absorption Columns, Virendra Kumar Mathur

Doctoral Dissertations

"A steady state approach was followed in this investigation to determine the effects of liquid and gas flow rates, packing size and packing height on the interphase mass transfer coefficient and gas phase axial mixing Peclet numbers. Experiments were performed on the absorption of carbon dioxide from a mixture of carbon dioxide and nitrogen in a packed column. Absorption was performed using 1/4, 3/8 and l/2 inch Raschig rings, with a packing height of 3 feet and also using 3/8 inch Raschig rings with a packing height of 5 feet. The liquid and gas flow ranges used were 2865 to …

Use Of The Turbulence Kinetic Energy Equation In Prediction Of Nonequilibrium Turbulent Boundary Layers, William Madison Byrne Jr.

Doctoral Dissertations

"A differential method is proposed for the prediction of a broad range of turbulent boundary layers of engineering and scientific interest. A digital computer program is presented which is applicable to boundary layers with positive, negative, and zero pressure gradient in the main-stream direction as well as boundary layers with suction, blowing or zero mass addition at the wall. The turbulence kinetic energy equation is solved simultaneously with the longitudinal momentum and continuity equations to provide an independent means for determining the effective viscosity which makes allowance for "history" effects in the flow. It is shown that the prediction method …

Voids In Neutron Irradiated Aluminum, Nicholas H. Packan

Doctoral Dissertations

"Void formation in high purity aluminum resulting from irradiation to fluences between 1.5 x 10¹⁹ and 1.6 x 10²² neutrons/cm² (E > 0 .1 MeV) at a temperature of 55 ± 5ºC was studied, primarily by means of transmission electron microscopy. In particular the effects of neutron fluence and flux were examined, as well as the possible influences of both preexisting and transmutation-produced impurities. A very low concentration of voids (about 10¹²/cm³) resulted from irradiation to 1.5 x 10¹⁹ neutrons/cm²; they averaged about 150 Å in diameter. Void concentrations and sizes increased with fluence, reaching values of 6 x 10¹⁴ voids/cm³ …

A Heuristic Algorithm For Determining A Constructive Suboptimal Solution To The Combinatorial Problem Of Facility Allocation, Harry Kerry Edwards

Doctoral Dissertations

"The major problem in plant layout is to determine the most economical relative location of facilities. There are two distinct types of suboptimal solutions to this combinatorial problem: construction and improvement. The writer has developed Modular Allocation Technique (MAT) which is the first useful construction suboptimal technique. The MAT general algorithm, a theorem relating the MAT solution to the optimal solution and an example problem are given. A computer program has been written that will apply MAT to the allocation problem for a maximum of 40 facilities. Results are given to demonstrate how MAT solutions may be used as initial …

A Study Of The Anodic Oxidation Of 1, 3-Butadiene On Platinum And Gold Electrodes, Arun Kumar Agrawal

Doctoral Dissertations

"The anodic oxidation of 1,3-butadiene on Pt and Au electrodes was studied at 70°C in solutions of H₂SO₄, K₂SO₄, K₂CO₃, and KOH with pH's ranging from 0.35 to 12.5. Reaction rates (current) were measured as a function of potential, pH, temperature, and butadiene partial pressure. A transition region (apparently a shift in the rate determining step) in case of Pt was observed in the Tafel plots. The coulombic efficiencies of oxidation to CO₂ were 85 percent in 1 N H₂SO₄ on Pt, 93 percent in 1 N KOH on Pt, and 72 percent in 1 N KOH on Au"--Abstract, Page …

Absolute Excitation Cross Sections Of He⁺ In 20-100 Kev He⁺-He Collisions Using Energy-Loss Spectrometry, Donald Roy Schoonover

Doctoral Dissertations

"Application of positive-ion energy-loss spectrometry has been extended to include experimental determination of absolute excitation cross sections of ground state helium ions. Helium ion-atom collisions were studied for impact energies ranging between 20-100 keV, in 10 keV intervals. The data were taken with an apparatus resolution between 0.6-o.8 eV FWHM. Cross sections for transitions from ground state to the second and third principal quantum levels of the ion plotted as a function of impact energy were still rapidly increasing at 100 keV. The cross sections at this energy were 1.64(± 0.28) x 10⁻¹⁸cm² for He⁺(l²s_1/2) -> He⁺(n = …

Simulation Of A Gas Storage Reservoir With Leakage By A Two-Dimensional Layered Mathematical Model, Steven William Ohnimus

Doctoral Dissertations

"A generalized mathematical model was developed for two-dimensional compressible fluid flow accounting for the effects of relative permeability capillary pressure, and gravity drainage in addition to the reservoir properties of rock heterogenity and reservoir geometry. The generalized model developed was applied to an aquifer gas storage reservoir in which vertical leakage occurred from the main reservoir to two adjacent overlaying zones. The experimental results of Thomas, et al. were utilized in applying the model to gas storage injection/withdrawal periods yielding reasonable results for the three layers"--Abstract, page ii.

Electrode Reactions In Zinc Electrolysis, Ernest R. Cole

Doctoral Dissertations

"The effects of temperatures from 0°C to 50°C and current densities from 10 asf to 200 asf on the current efficiency in the electrolysis of pure zinc sulfate solutions (65 gpl Zn⁺⁺ - 200 gpl H₂SO₄) were determined. Pure platinum and platinum coated titanium anodes were used with an aluminum cathode. Platinum anodes were not inert at certain combinations of temperature and current density, and platinum acted as a low overvoltage impurity causing resolution of the cathode deposit. Orientation of the zinc deposits was found to vary with temperature and to have a distinct relationship to current efficiency. Preconditioning of …

The Oxidation Kinetics Of Liquid Lead And Lead Alloys, Thomas Edward Weyand

Doctoral Dissertations

"Liquid lead and lead-silver alloys were investigated to determine the rates and products of oxidation in pure oxygen at temperatures of 350 to 600°C. The kinetic data were determined using a Cahn electro-balance. Liquid lead was found to follow a cubic rate of oxidation between 350 and 400°C. A parabolic rate was found at temperatures above 400°C. 0.496% silver and 2.258% silver alloys followed a cubic rate of oxidation from 350 to 550°C and tended to approach a parabolic rate of oxidation above this temperature. Silver additions were found to increase the rate of oxidation as compared to the pure …

A Computer Simulation Of Mine Air Shaft Thermodynamics, Ambyo Sumopandhi Mangunwidjojo

Doctoral Dissertations

"Several earlier investigations have been conducted into various aspects of heat problems in underground mines. The application of general gas laws and thermodynamics in the approach of mine ventilation has been helpful in elucidating certain difficulties associated with the subject. By combining several of the techniques perfected by these researchers and applying Carrier's method of calculation for heat flow from exposed rock strata into a workable plan, a method was developed whereby it is possible to accurately and conveniently predict the quality of working environment at any point within a deep mine. The findings of this study may be of …

Higher Space Mode Analysis Of A Large Cylindrical Pulsed H₂O System, Harold David Hollis

Doctoral Dissertations

"By utilizing a geometrically centered pulsed source internal to a large (B²_g) ≈ 0.002) cylindrical H₂O system, the neutron flux was measured as a function of position and time. A least square fit of the data yielded the fundamental and five higher decay constants and amplitudes of the thermal neutron flux. Symmetrical and enhanced neutron densities were obtained as a result of the internal source. Long waiting times were unnecessary and data acquisition was accelerated.

The decay constants were found to be independent of position, pulse width, counting time and rates, method of normalization, or waiting time. …

Binary Molecular Diffusivities In Liquids: Prediction And Comparison With Experimental Data, Ronald Dean Mitchell

Doctoral Dissertations

"The Eyring rate theory equation has been modified successfully to enable predictions of binary molecular diffusivities for a wide variety of liquid-liquid systems. The activation free energy for binary diffusion has been evaluated in terms of the activation free energies for self diffusion of the solvent and solute. This was accomplished through the use of regular solution theory by relating the bond breaking energy of the jump step to the bond breaking energy in evaporation. Diffusivities estimated by this equation and the equations developed by Olander, by Gainer and Metzner, and by Wilke and Chang were compared with experimental data. …

An Investigation Of The Stiffness Of Shafts With Integral Disks, Richard King Riley

Doctoral Dissertations

"The results of an investigation of the effect of an integral disk on the torsional elastic stiffness of an axisymmetric shaft are presented. Various configurations of disk diameters and widths on a shaft of specified diameter were investigated, using a finite element method of calculation verified by experimentation. The finite element method is presented for the elastic solution of a general axisymmetric body under all possible axisymmetric load conditions. The axisymmetric body is idealized as an assemblage of triangular cross-sectioned torii representing both the normal and shear properties. The elastic stiffness is used to obtain the equilibrium equations of the …

Development And Application Of Cartesian Tensor Mathematics For Kinematic Analysis Of Spatial Mechanisms, Robert Myrl Crane

Doctoral Dissertations

"The complexity of spatial mechanisms in themselves and the absence of an attractive analytical tool for their study has left this field of engineering analysis largely unexplored. In recent years several analytic methods have emerged. One of the most attractive of these is the tensor method. Literature surveys reveal that the tensor method is largely unexploited in the U.S.A., with regard to spatial mechanisms as well as simpler kinematic problems. The purpose of this work is to develop tensor mathematics for application to the kinematic analysis of spatial mechanisms. Methods are developed for position solutions and the determination of velocities …

Heuristic Algorithms For The Generalized Vehicle Dispatch Problem, Leland Ray Miller

Doctoral Dissertations

"A heuristic algorithm, called the sweep algorithm, is developed for the vehicle dispatch problem with distance and load constraints for each vehicle. A mathematical development and a step procedure for the sweep algorithm is given. Also given are eight problems and their solutions derived by the sweep algorithm. The solutions for this algorithm are compared with solutions from other vehicle dispatch algorithms, and the sweep algorithm is found to give better results for almost every problem. Various modifications are also presented for the sweep algorithm. A mathematical formulation is given for the vehicle dispatch problem with arbitrary cost functions at …

Temperature Variation In Distribution Of Relaxation Times In Aluminosilicate Glasses, David Wayne Moore

Doctoral Dissertations

"The distribution of relaxation times for the alkali peak in a Li₂ O·A1₂O₃ ·2.0SiO₂ glass and for the mixed alkali peak in a 0.5Li₂O·0.5Na₂O·A1₂O₃·2.OSiO₂ glass was studied using the internal friction technique. A lognormal distribution of relaxation times provided the best agreement with the experimental data. The ß parameter of the lognormal distribution function, which is related to the half-height peak width, varied with temperature, indicating that the distribution of relaxation times is dependent upon the activation energy and the activation entropy of the relaxation mechanism. The major contributor to the distribution of relaxation times is a wide distribution in …

The Deformation Mechanisms In Sublimed Magnesium Under Cyclic Loading, Babu Narian Thakur

Doctoral Dissertations

"A detailed study of the deformation processes in sublimed magnesium under reverse bending fatigue in air at room temperature has been undertaken utilizing the light, scanning and transmission electron microscopy. The Principal deformation modes are the basal slip and {10Ī2} twinning. The proportion of twinning increases markedly with the increasing stress level and the number of cycles. The evidence for cross slip is seen on the basal slip bands. The extrusions are seen not only along the basal slip lines but also along the {10Ī2} twin boundaries. In the later stages of fatigue, the extrusions chip off producing a notch …

The Electrochemical Behavior Of The Lead-Thallium System In Acidic Sulfate Solutions, Pedro Juan Aragon

Doctoral Dissertations

"Although the literature involving the corrosion of pure lead in sulfuric acid solutions is extensive, such studies still constitute an active field of investigation and debate. Much of the effort expended on this subject is due to the need of a better understanding of the reaction in lead storage batteries as well as of the mode of electrocrystallization processes. The resistance of lead to attack by sulfuric acid renders it an important coating material in this media. It is also often used in electrochemical synthesis because of its overvoltage characteristics. Unfortunately its mechanical properties are poor, and many ways have …