Digital Commons Network^™

Theory Of Nucleation Of Water Properties Of Some Clathrate Like Cluster Structures, Mehdi Daee

Doctoral Dissertations

"The tranquility of classical homogeneous nucleation theory has been disturbed by the introduction of statistical mechanical correction factors to a basically thermodynamic theory. These factors, which appear to be essential, destroy much of the agreement with experiment in the case of water vapor. A molecular model for the pre-nucleation water clusters is proposed with a view toward resolving some of these difficulties. As a first step, the Properties of a few specific cluster configurations have been examined. Clathrate-like structures containing 16 to 57 water molecules are discussed. The hydrogen bonds were treated as simple harmonic oscillators for the purpose of …

Use Of The Turbulence Kinetic Energy Equation In Analyzing Turbulent Near Wakes, James Edward Auiler

Doctoral Dissertations

"A general method is presented for analyzing turbulent flow fields in the near wake regions of two-dimensional and axisymmetric bodies. The governing partial differential equations of continuity, momentum and turbulence kinetic energy are expressed in elliptic form in terms of the dependent variables stream function, vorticity and turbulence kinetic energy. An iterative finite-difference technique is used to solve the governing equations simultaneously. Numerical solutions are obtained for the following physical problems: 1. Laminar near wake: Only stream function and vorticity are considered for laminar flow. Solutions are compared with available analytical results for uniform flow over a sphere. 2. Turbulent …

Homogeneous Nucleation Of Water Vapor In Inert Gas Atmospheres, Arthur Henry Biermann

Doctoral Dissertations

"The homogeneous nucleation of water vapor in atmospheres of helium, neon, argon, krypton, and xenon was studied using an expansion type cloud chamber. A strong dependence of the nucleation rate on the particular inert carrier gas was observed. At present the only dependence upon the nature of the carrier gas included in classical nucleation theories is a small factor arising from kinetic considerations which is in the wrong direction to explain the observations. To explain the dependence of the rate on the nature of the carrier gas, a molecular cluster model is assumed allowing inert gas atoms to occupy the …

Synthesis, X-Ray Characterization, Structural And Magnetic Studies Of A New Class Of Iso-Structural Bimo₃ Compounds, Joseph Donato Bucci

Doctoral Dissertations

"This dissertation consists of four sections. The first part is a temperature dependent X-ray study of the lattice parameters of BiFeo₃. The synthesis and subsequent X-ray characterization of BiCo₃, BiAlO₃, BiMnO₃ , BiScO₃, BiCo₁₋ₓFeₓO₃ , and BiAl₁₋ₓFeₓO₃ are reported in the second part. These compounds all crystallize in the body centered cubic (BCC) structure with a~10.2Å. Single crystal Precession and Weissenberg photographs confirmed the BCC structure. In part three, the results of the magnetic studies on BiCoO₃ and biAl.₉FE.₁ are presented. The magnetic data for BiCoO₃ are substantiated by X-ray thermal expansion studies. In the last part the compound BiCo.₉FE.₁O₃ …

Surface Plasmon-Longitudinal Optical Phonon Contribution To The Reflectivity Of N-Type Insb, William Eugene Anderson

Doctoral Dissertations

"The reflectivity of n-type InSb has been measured in the far infrared. The doping of the samples was such that the free-carrier plasma frequency was near the longitudinal optical phonon frequency. The results suggest that samples with a sufficiently thick damage layer show effects due to surface plasmons. The results also indicate that the surface plasma excitations are coupled to the phonons. A simple model of this coupling is presented which agrees qualitatively with the observed reflectivity. A somewhat more rigorous theory of the coupling is also presented"--Abstract, page ii.

Photoionization Of Photoexcited Cesium, Robert E. Hebner

Doctoral Dissertations

"A new method for obtaining the cross section for photoionization of photoexcited cesium is presented. The salient feature of this experiment is to use three crossed beams, i.e., two light beams intersecting a beam of cesium atoms. The cross section is determined by counting the ions produced by the two step process: Cs (6S) + h[upsilon]₁ --> Cs (6P) ; Cs (6P) + [upsilon]₂ --> Cs⁺ + e⁻ The relative cross section for the second step has been obtained from threshold (5060 Å) to 2500 Å. The excitation light source used in obtaining this cross section was a rf resonance …

Dynamic Behavior Of Eccentrically Stiffened Plates, Charles Stuart Ferrell

Doctoral Dissertations

"The dynamic behavior of eccentrically stiffened rectangular plates is studied by the finite element method. The addition of stiffeners to a plate structure is a common method of increasing the rigidity of the structure with a minimum of weight increase. However, this stiffened plate configuration does not easily lend itself to analysis. This study is an approach to finding a rational method by which the dynamic behavior of such a stiffened plate structure may be determined. The governing differential equations for the finite element model are derived and the stiffness and mass matrices for the plate and stiffener elements are …

Statistical Study Of Rock Drilling By Hypervelocity Jets From Explosive Shaped Charges, John William Brown

Doctoral Dissertations

"The drilling effect in rock of hypervelocity jets from explosive shaped charges was investigated experimentally to supplement a rapid excavation concept. The effects of the design factors of the charge and the mechanical properties of eight rock types were studied. Experiments were both designed and analyzed upon statistical principles. A full factorial experimental design was used for each of seven rock types. An analysis of variance and the k-ratio least significant-difference test were applied to the results.

The optimum design of shaped charges for drilling was found to be independent of rock type and rock properties. For composition C-4 charges …

Identification Of Linear Systems With Delay Via A Learning Model, Hugh Francis Spence

Doctoral Dissertations

"The effects of input delay on an identification scheme using a learning model are investigated. The parameter adjustment laws for the learning model are derived through Lyapunov methods similar to those used for the model reference adaptive control systems of Parks. For no measurement noise or delay mismatch between the learning model and system, the parameters are adjusted to bring the error between model and plant to zero. When there is delay mismatch between the inputs of the learning model and the unknown system, the convergence of the parameters of the learning model to those of the unknown system is …

Modeling The Visual Pathway For Interactive Diagnosis Of Visual Fields, Chiam Geoffrey Goldbogen

Doctoral Dissertations

"Visual fields are an important tool for the ophthalmologist in the detection, diagnosis, and monitoring of certain diseases and maladies of the visual pathway. The aim of the present research is to build a computer system which utilizes a learning machine to develop a mathematical model of the visual pathway. It is hoped that this system may be used in the field of ophthalmology as a teaching aid, or may assist in various aspects of diagnosis. Faults corresponding to blind or impaired areas of visual fields are extracted from medical records of a patient's condition. The structure of the model …

Metal Salt Catalyzed Carbenoids, Billy W. Peace

Doctoral Dissertations

"The interaction of diazomalonic esters with olefins in the presence of homogeneous copper(I) and copper(II) catalyst has been examined as a function of olefin structure, solvent media, ionic strength, catalyst structure and catalyst concentration, using partial rate data. It has been possible to determine the fine mechanistic details of the cycloproponation, C-H insertion and "dimer" forming reactions. The initial step is displacement of a ligand from copper by diazo compound in a pre-equilibrium, loss of nitrogen in the rate determining step, return of the ligand, displacement of metal from the carbenoid by olefin, followed by collapse to products. Studies revealed …

Noble Gases Anomalies In Terrestrial Ores And Meteorites, B. Srinivasan

Doctoral Dissertations

"Analyses of the content and isotopic composition of xenon and krypton in terrestiral ores containing tellurium, selenium or iodine resulted in the following conclusions: 1. The double beta-decay half-life for ¹³⁰Te is 2.51 x 10²¹ years from analysis of tellurobismuthite from Boliden, Sweden and 2.83 x 10²¹ years from analysis of tellurides from Kalgoorlie, Australia. 2. The ratio of the double beta-decay half-life of ¹²⁸Te relative to that of ¹³⁰Te is ≥ 108 and ≥ 293 for Boliden tellurobismuthite and Kalgoorlie tellurides, respectively. 3. Selenium minerals and tellurium ores containing selenium exhibit ⁸²Kr excess attributed to the double beta-decay of …

Absolute Cross Sections For Excitation Of Neon By Impact Of 20-180 Kev H , H₂ And He Ions, George William York

Doctoral Dissertations

"The technique of heavy-ion energy-loss spectrometry has been used to measure excitation cross sections for the (2p⁵)3s and (2p⁵)3p electronic configurations of Neon. The incident particles used were H⁺ , H⁺₂ and He⁺ at impact energies from 20-180 keV. The results are compared with previous optical measurements of the emission cross sections of lines from these levels as excited by H⁺ and He⁺ impact. Agreement is not good, either in shape or in absolute magnitude for excitation of the (2p⁵)3s configuration. However, agreement is surprisingly good for excitation of the (2p⁵)3p configuration. A curve fitting technique has been applied to …

An Investigation Of Subsequent Yield Phenomena, Joseph George Hoeg

Doctoral Dissertations

"A method utilizing high pressure fluid environments is described whereby a three-dimensional subsequent yield surface was determined for 304 stainless steel. Cylindrical parent specimens of this material were prestrained in axial compression under fluid pressure and then small sub-specimens were sectioned from these parent specimens. Finite element techniques were used to optimize the parent specimen size so that a zone of uniform axial stress would result during the prestraining. Longitudinal strains in this zone were monitored during the prestraining and the sub-specimens were cut from this region in a manner that did not allow the machining to appreciably affect the …

Distribution Of Trace Elements In Olivines And Proxenes - An Experimental Study, Melvin Leroy Bird

Doctoral Dissertations

"Olivine, pyroxene,and spinel were crystallized in the ternary system anorthite-forsterite-silica to which trace amounts of the transition metal ions Cr³⁺, Fe²⁺, Mn²⁺, Co²⁺, Ni²⁺, and Cu²⁺ had been added. The resulting concentrations of the transition metal ions in the liquid and crystalline phases were determined using the electron microprobe. The results, given as free energies and partition functions, indicate the order of substitution of the dipositive ions in all crystals to be Ni²⁺, Co²⁺, Mn²⁺, Cu²⁺, and Fe²⁺ according to the predictions of crystal field theory. The ion Cr³⁺ substituted in greater or lesser quantities depending on the crystalline phase. …

On-Line Economic Optimization Of A Chemical Reactor, Jesse Daniel Bennett

Doctoral Dissertations

"An economic optimizing control system for a continuous flow stirred tank chemical reactor is designed, simulated, and installed on a pilot scale reactor. The control scheme utilizes a reaction and reactor model to predict on-line the economic optimum of a reactant concentration. In this manner the control system manipulates the reactant flow rate to maintain the optimum concentration during changes in reaction-reactor parameters with time. Typical parameter changes include the decay of reaction catalyst activity. The optimizing controller will function in conjunction with various operating policies including control to maintain a specified production rate"--Abstract, page ii.

Response Surface Study Of A Characteristic Chemical Plant, John Thomas Mason Iii

Doctoral Dissertations

"Study of the return on investment response surface of a characteristic chemical plant indicates unimodality in the valid region, but the optimum design condition with this response surface is strongly affected by the correlation used for the investment. The method used for the design of this type of chemical plant incorporates the use of a simulation routine for preliminary estimates"--Abstract, page ii.

Some Statistical Inferences For The Bivariate Exponential Distribution, Bruce Mohr Bemis

Doctoral Dissertations

"The bivariate exponential distribution is neither absolutely continuous nor discrete due to the property that there is a positive probability that the two random variables may be equal. Basic properties of the distribution are presented as well as methods of parameter estimation including maximum likelihood. The distribution is shown to satisfy the usual regularity conditions in spite of its possession of a singularity. The maximum likelihood estimates are asymptotically efficient. Two other methods of estimation are compared with the maximum likelihood method in terms of efficiency. Tests of the hypothesis that two random variables each have independent exponential distributions versus …

Special Subrings Of Real, Continuous Functions, Paul Marlin Harms

Doctoral Dissertations

"Some lattice-ordered subrings of C(X) containing C*(X) are examined where X is a completely regular space. Each realcompact spaceY between [v]x and ßx is associated with a lattice-ordered subring of C(X) which is isomorphic to C(Y) and contains C*(X). The cardinal number of (ßX - [v]X) is a lower bound for the cardinal number of these subrings. Every prime ideal in each of these subrings is comparable with the intersection of the subring and a maximal ideal in C(X). The structure space of maximal ideals is studied for special subrings in C(X) containing C_K(X), the continuous functions of …

Trace Base Metals, Petrography, Rock Alteration Of The Productive Tres Hermanas Stock, Luna County, New Mexico, Peethambaram Doraibabu

Doctoral Dissertations

"Zinc, lead and minor copper-bearing manto-type and vein- type deposits occur in Paleozoic sedimentary rocks adjoining the Tres Hermanas quartz monzonite stock, Luna County, New Mexico. In an attempt to prove or disprove a possible genetic relationship between these mineral deposits and the stock, 99 half-mile or closer orthogonal grid samples from the stock and 22 soil samples from a connecting alluvial area to the north were analysed by atomic absorption technique for trace contents of zinc, lead and copper. Thirty-two of the rock samples were selected on a wider grid and petrographically studied and modal analyses calculated. Argillic, sericitic …

Transient Hydraulic Simulation: Breached Earth Dams, D. L. Fread

Doctoral Dissertations

"A conceptual method to alleviate flood damages due to over-topping failures of small earthfill dams is the incorporation of a relatively thin erosion retarding layer within the dam. This paper investigates the reduction in the reservoir release due to the hypothetical erosion retarding layer. In addition, the paper provides a method for the determination of an optimal location of the layer so as to minimize the maximum possible reservoir release due to a gradually breached earth dam. The transient reservoir flow is simulated by a numerical model, based upon the solution of the one-dimensional St. Venant unsteady open-channel flow equations. …

X-Ray And Mössbauer Spectroscopy Studies Of The Silicon-Antimony And Bismuth-Antimony Alloys, James Ralph Teague

Doctoral Dissertations

"X-ray and Mossbauer spectroscopy were used to investigate two antimony alloys, Bi-Sb and Si-Sb, showing semiconductorsemimetallic transitions or vice versa, depending on the antimony concentration in the host lattice. Resistivity and density measurements were found to be helpful in the analysis of the results. X-ray studies for dislocation-free antimony-doped silicon showed that the lattice constant of the alloy increased as the antimony concentration increased from 10¹⁸ to 10¹⁹ Sb atoms/cc. Rather good agreement was found between theoretical and experimental changes in lattice constant for dislocation-free silicon. Mössbauer studies showed that the isomer shift decreased linearly with increasing antimony concentration, which …

Feed Drive Design For Numerically Controlled Machine Tools, Subash Bhatia

Masters Theses

"The various types of feed drive control systems used in numerical control of machine tools have been broadly classified. Further a step by step design has been presented for the feed drive of a numerical contouring control milling machine. The aim has been to develop a consistent strategy for tackling a variety of such problems. Consequently stress has been laid on principles and not on design figures"--Abstract, page ii.

Frequency Division Using Cascaded Phase-Locked Loops, Curtis B. Abshier

Masters Theses

"In many practical communication systems it is necessary to generate phase coherent subharmonics of an input tone. A useful system for accomplishing this task is a system of phase-locked loops in cascade. It is shown that when the feed-forward function is matched, the phase error of the second loop is zero. Analytical analysis and computer simulation prove that the minimum time to achieve phase-lock is obtained when the feed-forward function is matched. Under this condition, necessary design parameters are determined with ease"--Abstract, page i.

A Time And Frequency Domain Approach To The Optimization Of Linear Multivariable Regulators, Eugene Charles Machacek

Masters Theses

"Optimal design and analysis of a multivariable regulator may be achieved in either the frequency or time domain. This paper describes the formulation of the matrix Riccati equation in the time domain and the Wiener-Hopf equation and the root-square-locus in the frequency domain. The necessary requirements which must be satisfied in order to achieve an optimal control vector when using a quadratic performance index are presented for both domains. The resultant optimal control vector is shown to be a linear function of the system state vector. The effect of the quadratic performance index weighting matrices on the optimal system closed-loop …

Ground Water Of The Uncompahgre Valley Montrose County, Colorado, Ted William Craig

Masters Theses

"Data from water quality tests of 50 wells and from general well information of 309 wells registered with the Colorado Division of Water Resources are presented for the area of Montrose County, Colorado, drained by the Uncompahgre River. This information, along with other pertinent information such as water laws and costs, is evaluated to determine the feasibility of increasing the use of ground water in the area. The drainage basin of the Uncompahgre River within the Montrose area bas three main geologic structures: the Uncompahgre uplift, the Montrose syncline, and the Gunnison uplift. All formations exposed in the area are …

A Computerized Decision Model For Making Quantitative Decisions With Regards To The Department Of Army's Equipment Improvement Recommendations, Lewis Neri

Masters Theses

"The management decision technique, currently in use, of determining priority of EIR evaluation is basically that of "feel and experience" along with the "most pressure" applied from outside the responsible organization. The feasibility of a computerized management decision concept has been studied at the lowest system with the objective of applying this to the next higher systems and finally arriving at an overall system value to obtain system priority. This study develops the technology of operations research and the associated computer techniques, delineates the problem and develops a mathematical model to simulate this management decision technique. Furthermore, it utilizes logical …

The Effect Of Channel Errors In The Differential Pulse-Code-Modulation Transmission Of Sampled Imagery, Roger J. Arguello, Harvey R. Sellner, John A. Stuller

Electrical and Computer Engineering Faculty Research & Creative Works

This Paper Presents an Analysis, Simulation, and Discussion of the Effects of Communication Errors on Four-Bit Differential Pulse-Code Modulation (DPCM) Sampled Imagery. Simulations Are Presented that Describe the Effects of Inserting Periodic "PCM Updates" in Order to Correct Communication Errors in the DPCM Transmission of Photographic Scenes that Have Been Scanned and Sampled at the Nyquist Rate. Copyright © 1971 by the Institute of Electrical and Electronics Engineers, Inc.

The Missouri Miner, December 09, 1970

The Missouri Miner Newspaper

No abstract provided.

Missouri S&T Magazine, December 1970, Miner Alumni Association

Missouri S&T Magazine

No abstract provided.