Digital Commons Network^™

Electro-Reduction Of Bromate On Mercury, Jaw-Shin Chang

Doctoral Dissertations

"The electrochemical reduction of BrO⁻₃ was studied on a stationary Hg electrode in neutral and basic solutions containing K⁺, Na⁺, and L⁺. Coulombic efficiency studies showed Br⁻ to be the predominant reduction product. The steady state kinetic parameters include Tafel slopes of ca. -0.120 V, approximate first order activity dependences for both BrO⁻₃ and the accompanying cation, and no pH dependence. A reaction scheme is proposed which involves BrO⁻₃ "bridged" to the electrode by the accompanying cation. It is suggested that the "bridging" is a result of ion-pairing in the electrical double-layer"--Abstract, page 1.

Scavenging Of Atmospheric Particles By Water Drops, Ming-Shian Wu

Doctoral Dissertations

"In the first paper, the mechanisms of particle capture and coalescence of aerosols by a moving water drop in the atmosphere are studied using the boundary-layer flow approximation. The particle trajectory is computed by solving the equations of motion of the particle both outside and inside the boundary layer using the Adams-Moulton method. The grazing trajectory is found by a trial-and-error technique. The collision and collection efficiencies of scavenging due to particle inertia and to the velocity gradient of the flow field are then computed for water drops ranging from 0.1 to 1.0 mm in radius and for particle of …

Measurement Of Molecular Diffusivities Of Liquid Alkane Systems, James W. Moore

Doctoral Dissertations

"An unsteady-state porous frit method of diffusion coefficient measurement, recently developed in this laboratory, was improved and expanded upon. The experimental technique has been refined and documented. The unsteady-state diffusion of an initially 0.5 N NaCl solution into pure water (effective diffusivity -1.480 x 10^-5 cm²/sec) was employed as the calibration standard. An overall calibration precision of ±4% was obtained. Diffusion times of two hours or less were used for the non-aqueous diffusivity measurements. The validity of this measurement technique was confirmed by the agreement of the measured self-diffusion coefficient of n-heptane (25⁰C) with literature values.

A …

Petrography, Diagenesis And Environment Of Deposition Of The Gasconade Formation, Lower Ordovician, Southern Missouri, Abd El-Aziz El-Hady A. Borahay

Doctoral Dissertations

"The Gasconade Formation (Lower Ordovician) has been studied in the surface and subsurface in the Ozarks of Missouri and northeastern Oklahoma. The formation is mostly dolomite with a sandstone member at the base (Gunter) and frequent occurrences of chert bodies of different shapes particularly in the middle part.

The dolomite crystals in the lower and upper parts are subhedral to euhedral of equicrystalline to two-size fabric and range in size from 300-600 microns, and subhedral to anhedral of variable fabric and smaller size in the middle part. A sequence of cloudy and clear areas, named zoning, characterizes the euhedral crystals. …

Investigation Of Roof Shales In Illinois Coal Mines, Peter J. Conroy

Doctoral Dissertations

"This thesis describes an investigation of the relationships among the composition, physical properties and the performance of roof shales in Illinois coal mines. The study included cataloging the physical and mineralogical properties of typical roof shales, determining the interrelationships of the properties and defining the factors in the rock which effect deterioration. From the results, a classification system has been developed which may provide a means for evaluating coal mine roof stability.

A coring apparatus was developed for obtaining in situ samples from mine roofs. Five coal mines with varying geologic and roof conditions were sampled. Precautions were taken to …

Approaches To The Synthesis Of Azabullvalene, Thomas Rudolph Steinheimer

Doctoral Dissertations

"Three approaches to the synthesis of the heretofore unknown azabullvalene, the pi electron equivalent heterocyclic congener of bullvalene itself, are described. Two of the schemes are based upon the assumption that the most convenient method for the introduction of the nitrogen atom is via thermal rearrangement of the appropriate azide.

The first involved the generation of the homobarrelene carbon skeleton and sub sequent decomposition of its azide. This compound arises formally as the product of the Diels-Alder addition of acetylene to the bicyclic valence isomer of tropyl azide (cyclohepta-1, 3, 5- trienyl-7-azide). In order to achieve this goal, Diels-Alder additions …

The Effects Of High Pressure And Temperature Environments On The Properties Of 6061-T651 Aluminum, Patrick George Davidson

Doctoral Dissertations

"During this experimental testing program the effects of the simultaneous application of high pressure and temperature environments on the mechanical properties of 6061-T651 aluminum were analyzed. From the data obtained at the yield and ultimate points a yield and ultimate model was developed based upon the parameters effective stress, effective strain, and the hydrostatic component of stress. This model was obtained solely from the data acquired from uniaxial tensile specimen tested at various pressures and temperatures. Two other loading paths--biaxial tension and torsion--were then used to verify the accuracy of the model. From the testing program, data were also obtained …

Prebainitic Phenomena In Aisi 86b80 And 0.8c-5.3ni Steels, Chung Lim

Doctoral Dissertations

"An ultrasonic investigation shows that the prebainitic kinetics of AISI 86B80 and 0.8C-5.3Ni steels follow t^2/3 and or t¹ time laws in the lower bainite temperature region. The data analysis indicates that these kinetics signal carbon segregation to dislocations. The simple time laws are interrupted at the bainite start time. It is shown that at this time the carbon depleted regions around dislocations transform martensitically. The lower bainite reaction is thus initiated by the formation of supersaturated ferrite through carbon segregation and the subsequent local martensitic transformation"--Abstract, page iii.

A Study Of Gas-Surface Interactions Through Sticking Coefficient, Condensation Coefficient And Sublimation Rate Measurements, Charles E. Bryson Iii

Doctoral Dissertations

"The behavior of the sticking coefficient of CO₂ on an H₂O substrate as a function of time is interpreted in terms of a microscopic nucleation theory. For a substrate temperature near 75 K and an incident flux near 10¹³ molecule cm⁻² sec⁻¹, a critical cluster size of four molecules and and activation energy of nucleation of 22 ± 2.4 Kcal mole⁻¹ is obtained. The analysis treats the nucleation processes as continuous rather than as a discontinuous process at some critical temperature.

In addition the same molecular beam apparatus used for the above experiment was used to measure the condensation …

Hydrostatic Extrusion Of Waste Glass And Plastic, Subhash Govind Kelkar

Doctoral Dissertations

"Waste glass and waste plastic combine to form a major portion of nonbiodegradable, solid waste. These waste products aggravate the already too serious problem of environmental pollution. Hence, a means is sought of utilizing this waste in the construction industry, thus solving two problems simultaneously - that of beautifying the environment, and of procuring inexpensive building materials.

Extrusion is not an uncommon process as far as the manufacture of original products is concerned. Hydrostatic extrusion is a modification of the process wherein a billet or slug of some material is forced to flow through a die under the influence of …

Applications Of Frequency Domain Stability Criteria In The Design Of Nonlinear Feedback Systems, Allen Joseph Rushing

Doctoral Dissertations

"The Popov criterion for absolute stability of nonlinear feedback systems is applied to several example problems. Model transformations such as pole shifting and zero shifting extend the class of systems to which the criterion applies. Extensions of the criterion having simple graphical interpretations yield stronger results for systems with constant monotonic slope-bounded nonlinearities. Additional extensions lacking simple graphical interpretations in the complex plane are also demonstrated by example.

Stability throughout a region in parameter space is discussed, and the Kalman conjecture is verified for a new class of systems. The Popov criterion is also used to prove BIBO stability, process …

Some Results On Quasi-Uniform Spaces, Karen Sylvia Carter

Doctoral Dissertations

"An example of a quasi-uniform space which is complete but not strongly complete is constructed. We also give an example to show that a T₁ space does not necessarily have a T₁ strong completion.

The definition of Cauchy filter is discussed. An alternate definition, referred to as C-filter, is considered. A construction of a C-completion is given and it is shown that if a quasi-pseudometric is complete, then the corresponding quasi-uniform structure is C-complete.

Conjugate quasi-uniform spaces are discussed. A theorem relating a transitive base of a quasi-uniform structure to a transitive base of the conjugate structure is …

A Stochastic Theory Of The Stepwise Growth Of Ice Crystal Surfaces, Andreas Kasimir Goroch

Doctoral Dissertations

"Previous theories have had limited success in explaining the presence of a peak in the behavior of the rate of advance of a step on an ice crystal surface with respect to temperature. In the present work we examine the temperature dependence of the advance of steps on the basal face of an ice crystal from several points of view. An alternate derivation is presented for the random motion of adsorbents on a cubic lattice with absorbing points, and this theory is applied for the advance of a step on an ice surface. The velocity of step advance according to …

Methods For Predicting The Influence Of Intense Sound, Steady Flow, And Elevated Temperature On The Acoustic Performance Of Automotive Exhaust System Components, Richard Chuka Oboka

Doctoral Dissertations

"The principal objective of this investigation was to study the feasibility of developing laboratory techniques for automobile-exhaust muffler design in order to reduce the amount of on-vehicle trial-and-error testing currently required. The investigation included (1) improving the capability of existing laboratory equipment to simulate the conditions in automobile exhaust (i.e., high-amplitude pressure waves, steady flow, and elevated temperature), and (2) theoretical and experimental studies of typical acoustic elements (side-branch resonators, expansion chambers, louvered tubes) used in muffler design. The sound fields used for these studies included pure tones, single pulses (tone bursts), random noise, and simulated automobile exhaust noise.

Empirical …

The Atomic Absorption Determination Of Ultra-Trace Tellurium In Rocks Utilizing High Sensitivity Sampling Systems, Richard D. Beaty

Doctoral Dissertations

"The sampling boat and the graphite furnace have been shown to possess the required sensitivity to detect tellurium at ultra-trace levels, in a variety of sample types, by atomic absorption. In the sampling boat approach, tellurium in sample solutions is chemically separated and concentrated by extraction into methyl isobutyl ketone before measurement. For samples exhibiting extraction interferences or excessively high background absorption, a preliminary separation of tellurium by coprecipitation with selenium is described. Using this technique, tellurium can be quantitatively detected down to 5 nanograms and linear response is observed to 100 nanograms. Relative standard deviations of better than 7% …

Film Boiling Of Freon 113, Normal Pentane, Cyclopentane, And Benzene From Cylindrical Surfaces At Moderate Pressures, Gary Joseph Capone

Doctoral Dissertations

"An investigation of film boiling heat transfer in saturated pools of liquid Freon 113, Normal Pentane, Cyclopentane, and Benzene was made. The fluids were boiled from copper, cylindrical heat transfer surfaces, 3 inches long, and 0.55, 0.75, and 1.00 inch in diameter. The heat transfer elements were positioned horizontally in an autoclave and tested at moderate pressures of up to a pressure of 242.5 psia for Normal Pentane.

The experimental data are discussed and compared with known film boiling correlations. The known correlations were found to be inadequate in predicting heat transfer coefficients as a function of pressure, temperature difference …

Absolute Differential Elastic And Inelastic Cross Sections In 25-140 Kev He⁺ + He Collisions, Victor Pol

Doctoral Dissertations

"The UMR heavy-ion energy-loss spectrometer has been modified to study the angular dependence of elastic and inelastic scattering for 25-140 keV He⁺ incident on He. The data were obtained as energy-loss spectra at angles from 0 to 7.3 x 10^-3 rad (c.m.) with energy-loss resolution of 0.6 to 1.0 eV and angular resolution of 1.2 x 10^-3 to 2.4 x 10^-3 rad (c.m.). From the spectra we have calculated average differential cross sections for elastic scattering, direct excitation of the individual He(n=2) states and direct excitation of the He⁺(n=2) states. By integrating the differential …

Charge Transfer Between Oˉ Ions And O₂ Molecules In The Ground State And Singlet Delta Excited State, Ronald Floyd Mathis

Doctoral Dissertations

"A crossed-beam apparatus has been built and used to study charge transfer between O⁻ ions and O₂ molecules in the ground state and in the metastable, singlet delta, excited state. The energy of the incident ions ranged from 10 to 10,000 eV.

The cross section for charge transfer between O⁻ and ground state O₂ was found to peak at about 5 keV, as predicted on the basis of the Rapp and Francis theory. At the lower energies there is good agreement with the previous measurements of Snow et al., and Rutherford and Turner, who also used crossed beam techniques. The …

Analysis Of Continuous Curvilinear Structures By Infinite Matrix Series Methods, Trinh-Ngoc Rang

Doctoral Dissertations

"The objective of this dissertation is to present two methods of structural analysis for continuous curvilinear frames by using infinite matrix series as an extension of the well-known moment-distribution method. The sum of all unbalanced moments and thrusts relaxed at joints of a continuous system can be expressed in a compact and exact mathematical expression, which is in terms of the sum of a convergent infinite matrix series. With these unbalanced forces at joints, the final support forces may be calculated in a single stage of distribution and carry-over. The convergence of the balancing process is also demonstrated. Approximate results …

Nonlinear Optimum Design Of Dynamic Damped Structures, Mark E. Botkin

Doctoral Dissertations

"A method to optimize the weight of plane frames subjected to dynamic loads is presented. Restrictions are imposed upon the maximum dynamic stresses and displacements, desirable section moduli of the constituent members, and the range of values allowed for natural frequencies. Various considerations for rigid frame design include damping, the P-Δ effect, static girder loads, static column loads and girder shears transferred to the columns. A finite difference approach is presented to evaluate the shock spectrum which is used in conjunction with modal superposition to obtain the peak upperbound dynamic displacements and stresses for multistory and multibay frames. The displacement …

Anionic Polymerization Of A Series Of 5-Membered Cyclocarbosiloxanes, Balaraman Suryanarayanan

Doctoral Dissertations

"A study has been made on the anionic polymerization of a series of 5-membered cyclocarbosiloxanes with methyl and/or phenyl substituents. The polymerization was initiated by lithium n-butyldiphenylsilanolate in the presence of tetrahydrofuran. Six 5-membered cyclocarbosiloxanes (2,2,5,5-tetramethyl-1-oxa-2,5-disilacyclopentane; 2,2,5- trimethyl-5-phenyl-1-oxa-2,5-disilacyclopentane; 2,5-dimethyl-2,5-diphenyl- 1-oxa-2,5-disilacyclopentane; 2,2-dimethyl-5 ·,5-diphenyl-1-oxa- 2,5-disilacyclopentane; 2-methyl-2,5,5-triphenyl-1-oxa-2,5-disilacyclopentane; 2,2,5,5-tetraphenyl-1-oxa-2,5-disilacyclopentane) were synthesized. Since the chemical shifts of the protons of the cyclic monomers and the polymers formed were different, the rate of polymerization of the cyclic monomers was measured utilizing an NMR spectrometer. The effects of tetrahydrofuran concentration, initiator concentration and water concentration on the rate of polymer formation and on the molecular weight of …

Initial Surface Reactions And Nucleation Kinetics Of Boron On Atomically Clean Molybdenum Substrates, Richard Eugene Moore

Doctoral Dissertations

"A study of the chemical vapor deposition (CVD) of boron from boron triiodide (BI₃) on molybdenum has been done with field emission microscopy (FEM) and low energy electron diffraction (LEED).

A correlation of the efficiency by which BI₃ is effectively dissociated to form adsorbed boron, and the temperature of the substrate has been shown through work function measurements on the boron covered molybdenum field emitter surfaces. The boron-induced work function change of molybdenum has been shown to be in agreement with a theoretical model which predicts positive, as well as negative work functions for adsorbate-substrate systems. It …

Implementation Of Recursive Algorithms For Delay-Time Estimation Using The Fast Walsh Transform, Donald Robert Nelson

Doctoral Dissertations

"Use of the fast Walsh transform to resolve noisy signals into Walsh function series to digitally implement maximum-likelihood parameter estimators for real-time use is investigated. Realization of estimators which seek a null in the derivative of the log-likelihood function, instead of direct maximization, results in feedback algorithms which yield considerable savings in computation time and storage. Performance of these feedback delay-estimation algorithms is characterized in terms of mean-squared error (MSE) and response to a delay step by Monte Carlo simulation. The effect of changing the number of points in the transform on the MSE is also investigated. Hard limiting of …

Film Boiling Of Benzene, Freon 113, Freon 11, And Normal Pentane From Horizontal Surfaces At Atmospheric Pressure, Richard Stanley Kistler

Doctoral Dissertations

"A film boiling study was conducted with five different area flat plates at atmospheric pressure for benzene, Freon 113, Freon 11, and n-pentane. The heat transfer surface was horizontal for all tests.

The data were compared to the correlations commonly used for heat transfer. The common correlations were found to be in error for small surface sizes, but adequate for all fluids except benzene for the largest surface, a semi-empirical equation which correlates the available data as a function of surface diameter was derived and discussed"--Abstract, page iii.

An Application Of Residual Relaxation To Mathematical Simulation Of Petroleum Reservoirs, Grufron Achmad

Doctoral Dissertations

"Stability and convergence have long been primary concerns in the application of numerical techniques to the simulation of petroleum reservoir performance. An iterative method based on sequentially reducing the residual to zero at each grid point has been developed. It has been shown analytically that this residual relaxation method is stable, convergent, and consistent.

A three-phase areal model was developed to simulate a hypothetical homogeneous petroleum reservoir, and various computational methods were tested with this model. The residual relaxation method developed in this study (RELAX) was found to converge as rapidly as SIP, and much faster than either LSOR or …

Linear Stability Of Non-Parallel Flow In The Entrance Region Of Ducts, Francis Chung-Ti Shen

Doctoral Dissertations

"An investigation is made of the linear stability of the developing flow of an incompressible fluid in the entrance region of annular ducts, circular tubes, and parallel-plate channels. Small axisymmetric disturbances for annular duct and tube flows and small two-dimensional disturbances for channel flow are considered in the analysis. In formulating the stability problems, account is taken of the transverse velocity component of the mainflow. This results in the modified Orr-Sommerfeld equations, one for annular duct and tube flows and the other for channel flow. The mainflow velocity fields utilized in the stability analysis are those from the solutions of …

Rock Fragmentation By Subsurface Thermal Inclusions - A Finite Element Study, Mahendrakumar Ramkrishna Patel

Doctoral Dissertations

"Although rock tunneling machines are being used extensively with performance and cost advantages over traditional drill and blast methods, their usefulness for hard rock excavation is far from being practical due mainly to the inability of present day mechanical cutters to penetrate these rocks economically. Among various novel techniques that are being investigated, internal heating methods seem to be the most promising. This investigation is concerned with a feasibility study of thermal rock fragmentation using heat to create in-depth thermal inclusions.

The three-dimensional problem of in situ rock fragmentation involves parallel rows of equidistant holes drilled to a constant depth. …

A Study Of The Pulse-Height Response Of Silicon Surface-Barrier Detectors To High-Energy Heavy Ions, Gregory Dan Smith

Doctoral Dissertations

"The pulse-height defect (PHD) of high-energy heavy ions in silicon surface-barrier detectors can be divided into three components: (1) energy loss in the gold-surface layer, (2) a nuclear-stopping defect, and (3) a defect due to recombination of electron-hole pairs in the plasma created by the heavy ion. The plasma recombination portion of the PHD was the subject of this study using the variation of the PHD with (1) the angle of incidence of incoming heavy ions, and (2) changes in the detector bias. The Tandem Van de Graaff accelerator at Argonne National Laboratory was used to produce scattered beam ions …

A Study Of The Dynamic Loading Of Hydrodynamically Lubricated Journal Bearings, Nader Khorzad

Doctoral Dissertations

"The analytical and experimental investigation presented here examined the response of a full journal bearing to a unidirectional dynamic load. Frequency response of the bearing at different eccentricity ratios was investigated. It was concluded that the response of the bearing varies with eccentricity. The experimental data obtained was compared to an analytical model which considered inertial, damping, and elastic characteristics of the lubricant film. An investigation of film pressure revealed that the pressure due to journal center acceleration is smaller than the hydrodynamic and squeeze-film pressures"--Abstract, page 1.

Auger Satellites Of The L₂₃ Auger Emission Bands Of Al, Si, And P, John Junior Melles

Doctoral Dissertations

"In this study a detailed investigation of the high energy satellites of the L₂₃ Auger emission bands of Al, Si, and P was made. The satellites are interpreted as arising from double ionization of the L₂₃ shell rather than from a plasmon gain process. The parent-satellite energy separations, ΔE, between like structures were determined and were found to be consistently smaller than the volume plasmon energies measured for the same samples. A comparison of Si and SiO revealed no evidence that ΔE for Si is dependent on the volume plasmon energy of the sample.

The satellite threshold excitation …