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A Study Of The Supercooling Behavior Of High Purity Liquid Bismuth, B. L. Bramfitt

Doctoral Dissertations

"This investigation involves a study of the supercooling behavior of pure bismuth as affected by the melting atmosphere, the amount of superheat, and the intentional addition of metallic and non-metallic foreign materials to the melt. It was found that the amount of oxide on the melt surface is a controlling factor in the degree of supercooling obtainable in bismuth. In the presence of a thick bismuth oxide surface layer the amount of superheat below a 15°C drastically decreases the amount of supercooling due to the retention of nuclei in the surface film that promote nucleation upon cooling of the melt. …

Aeration Studies In Submerged Fermentations Using A Steam-Sterilizable Dissolved Oxygen Sensor Of Improved Design, Carl J. Wallace

Doctoral Dissertations

"Large-scale submerged fermentations have been important for many years for the production of antibiotics, vitamins, enzymes, etc.; however, aeration studies have been severely restricted in these processes because of the unavailability of adequate oxygen sensing equipment.

A steam-sterilizable oxygen sensor of improved design was developed out of an investigation of several potential sensors. This rapidly responding galvanic probe made use of a lead anode, a silver cathode, an acetate buffer as the electrolyte, and a one mil Teflon® membrane as the diffusion barrier. Its sensitivity was approximately 40 µamps and full response required approximately 5 minutes.

Use was made of …

An Investigation Of The Induction Heating Characteristics Of Powdered Susceptors Dispersed In A Non-Conducting Medium, Robert Leon Wright

Doctoral Dissertations

"This investigation determined some of the induction heating characteristics of powdered magnetite, iron and ferrosilicon susceptor dispersed in silica sand which had been coated with thermosetting resin. The powdered susceptor particles in the mixture were heated by the field of an induction coil, consequently heating the resin coated sand and bonding the sand grains together.

It was found that the type, relative amount,and particle size of the susceptor were important variables to be considered in the induction heating characteristics. Hysteresis losses in the susceptor particles, which are a function of the coil current, frequency, and permeability, appear to be the …

Cenozoic And Recent Lunulitiform Bryozoans Of The Gulf And Atlantic Coasts, Ronald Greeley

Doctoral Dissertations

"Free, cup-shaped colonies of cheilostomatous bryozoans, equipped with vibracula, are termed lunulitiform bryozoans. This group is found in sandy and calcareous Cenozoic deposits of the Gulf and Atlantic Coastal Plains. Cupuliform bryozoans are taxonomically distinct from, but in many ways similar to, lunulitiform bryozoans; the two groups are frequently found together.

Known lunulitiform genera of the Gulf and Atlantic Coastal Plains are diagnosed and their species described: Lunulites Lamarck, fifteen species, one new; Oligotresium Gabb and Horn, six species, two new; Discoporella d'Orbigny, two species; Cupuladria Canu and Bassler, two species; Selenaria Busk, one species; Otionella Canu and Bassler, four …

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 …

Hydrogen Absorption And Corrosion Studies Of Zone-Refined Iron, Chang Don Kim

Doctoral Dissertations

"The lattice constants of zone-refined iron filings and iron whiskers are 2.86623 and 2.86626 Å at 25°C respectively. Their thermal expansion coefficients are both the same, 12.1 x 10⁻⁶ /°C at temperatures 10 - 65°C.

The influence of hydrogen on the lattice constant of iron was investigated and it was found that hydrogen has no effect (within the limits of errors) on the lattice constant of iron at room temperature regardless of the charging methods. However, at elevated temperatures hydrogen expands the iron lattice due to increased solubility of the gas. The lattice constant of iron in vacuum and in …

The Statistical Mechanics Of Kink Interactions, Michael Brewer Mcneil

Doctoral Dissertations

"Using a potential derived from continuum elasticity, the interactions between kinks on a dislocation line are studied as special cases of the problem of a one-dimensional system of interacting particles. By the use of constant pressure ensembles, the principal kink-interaction problems of physical interest are solved. The application of these solutions to the theoretical analyses of work hardening and internal friction is explored and comparisons made to previous work in which kink interactions were neglected; it is found that, as would be expected, variations of equilibrium kink populations with external stress cannot account for the Bordoni peak, which must therefore …

A Study Of (Deuteron,Proton) Reactions On Light Nuclei From 200 To 350 Kev, Joel Edward Henkel

Doctoral Dissertations

No abstract provided.

The Addition Of Trimethlytin Hydride And Trimethylgermanium Hydride To Dienes, Richard Herbert Fish

Doctoral Dissertations

No abstract provided.

The Effects Of Dietary Phosphorus On The Absorption, Deposition And Excretion Of Copper In Calves Supplemented With Molybdenum Or Molybdenum And Sulfate, Donald Eugene Keyser

Doctoral Dissertations

No abstract provided.

Stereochemical Studies Of (Pos Rot-)-1-Methyl-2,6-Diphenyl-4-Piperidone Oxime, Evelyn Josephine Tyminski

Doctoral Dissertations

No abstract provided.

Variation In Gold Content Of Minerals Of The Marysville Quartz Diorite Stock, Montana, Erwin Joseph Mantei

Doctoral Dissertations

"The purpose of this thesis was to study the amount and distribution of gold in the minerals of the Marysville quartz diorite stock, Montana. Twenty-eight rock samples were collected from various parts of the Marysville Stock, using a NS-EW grid sample pattern. Thirty additional samples were collected from selected localities and from the vicinity of the gold mines which occur around the periphery of the stock. By use of a hand magnet and a Frantz isodynamic separator, the magnetite, biotite, hornblende, and quartz-feldspar portions of the various rock samples were isolated and purified to between 90-99 percent purity. Eighteen thin …

A Solution To Einstein's Gravitational Field Equation For A Spherically Symmetrical Static Perfect Fluid, Lionel Donnell Hewett

Doctoral Dissertations

"Given spherical symmetry, Einstein's gravitational field equations are reduced to a single, second order, linear, homogeneous differential equation. The solution of this equation for a homogeneous sphere is identical with Schwarzschild's solution...Values of relative density, interior mass, relative pressure, relative and absolute temperature are obtained as functions of radius, r, and are compared with corresponding values for the homogeneous sphere, and for a model sun"--Abstract, page v.

An Investigation Of Current Induced Mass Migration In Solid Metals, Steven Mitchell Kovel

Doctoral Dissertations

"In this investigation of current induced mass transport, the general phenomenological equations will be considered first so as to present a picture of the experimental situation. The theoretical computations are then divided into four sections: (1) the determination of the force on a defect due to electron scattering, (2) a discussion of how the force on the defect might be shared by the surrounding ions, (3) how an external force affects the diffusion frequency of an ion, and (4) what the rate of mass transport is under the influence of an electric field. So as to simplify the discussion and …

Pair Distribution For A Cell-Model Liquid, James M. Phillips

Doctoral Dissertations

"The pair distribution function for a cell-model liquid has been derived by Lund in the form of an integral equation which depends upon the cell-center distribution function and the cell model. From this integral equation an approximate integral equation is obtained by substituting a function, which is linearly dependent upon the molecular pair distribution function and a variable parameter for the cell-center distribution function. This approximate integral equation is solved for the molecular pair distribution and the variable parameter is shown to depend upon the difference between temperature and the critical temperature. Although the exact numerical solution of the molecular …

Internal Friction Of Mixed-Alkali Silicate Glasses, James E. Shelby

Doctoral Dissertations

"The mixed alkali effect in silicate glasses was examined from internal friction measurements made over the temperature range from -190 to 500⁰C and at a frequency of 0.4 Hz. Supplemental measurements of the activation energy for the different internal friction peaks, dynamic shear modulus, density, and index of refraction were also made. All measurements were confined to silicate glasses containing mixtures of Li-Na, Li-K, Li-Rb, Li-Cs, Na-K, Na-Rb, Na-Cs, and K-Rb. Rötger's interpretation of the internal friction of mixed-alkali silicate glasses is shown to be incorrect. A previously unreported internal friction peak was observed whenever two different alkali oxides were …

Drag Reduction In Newtonian Polymer Solutions, Harry C. Hershey

Doctoral Dissertations

"Prior work in the area of drag reduction has been mainly limited to aqueous solutions. Theoretical and empirical analyses of the resulting data in aqueous solutions have been hindered by the fact that some polymers cause drag reduction and others do not...This investigation was directed to the study of how the size and configuration of the polymer molecule in solution affected drag reduction and the related phenomenon of turbulence suppression. Apparatuses were designed and built to measure viscometric flow, curves, friction factors, velocity profiles, and normal stresses (by a jet thrust technique developed by Metzner and associates)"--Summary, page 1-2.

An Introduction To Linear Time-Variant Digital Filtering Of Seismic Data, Richard Harold Lassley

Doctoral Dissertations

"The exploration geophysicist is constantly searching for new and better methods for analyzing seismic data. The primary purpose of this dissertation is to introduce linear time-variant digital filters as a technique for the filtering of seismic data. Methods of characterizing linear time-variant digital filters are discussed in general terms. The advantages of the different impulse and frequency responses are cited. In addition, the meanings and possible interpretations of the time and frequency variables introduced are considered. The concept of linear time-variant digital delay filters is presented along with their relationship to impulse responses. A pictorial diagram of discrete time-variant impulse …

A Study Of Near Surface Elastic-Anelastic Layers, Charles Allen Aldrich

Doctoral Dissertations

"Wave propagation through layered media is of importance in many disciplines. The near surface layers are of special significance, in that most measurements of waves are made within these layers. The purpose of this investigation was to formulate mathematical models with which to analyze the effects of near surface layering"--Introduction, page 1.

Decay Of Certain Mercury Lines In Argon, Thallium, And Pure Mercury Atmospheres, Edward E. Stepp

Doctoral Dissertations

"Organization of thesis and Hg-A study, The time decay of the intensity of selected mercury lines was examined under three different conditions, Each section of this thesis i s divided into three parts corresponding to these three different conditions, In each section part A concerns the decay of intensity of the 2537, 4079, 4360, and 5462 A mercury lines, following the excitation of the states from which they originate by an Hg-A de discharge, Part B concerns the decay of intensity of 14 mercury lines following the excitation of the originating state of these lines by an intense r-f discharge …

Stratigraphy, Sedimentation And Structure Of The Upper Cherokee And Lower Marmaton (Pennsylvanian) Rocks Of Bates County, And Portions Of Henry And Vernon Counties, Missouri, Richard J. Gentile

Doctoral Dissertations

"The major purpose of this dissertation is to describe in detail the stratigraphy of the upper Cherokee and lower Marmaton groups of the Middle Pennsylvanian, Desmoinesian Series in a portion of western Missouri. The stratigraphy of the upper Cherokee and lower Marmaton groups in areas of Kansas west of the project area has been studied by several workers. The most recent contributions have been by Jewett in 1941 and 1945, and by Howe in 1956. Detailed geological mapping also has been completed under the direction of the Missouri Geological Survey in areas to the east of the project area. Most …

Relation Of Stem Pitting Of Apple To Other Apple Virus Diseases, Richard Caswell Mc Crum

Doctoral Dissertations

No abstract provided.

Part I: Stereochemistry Of Allenes Part Ii: The Reaction Of Phenyl(Phenylethynyl)-Tert-Butyl Carbinol With Peroxyacids, Eugene William Byrnes

Doctoral Dissertations

No abstract provided.

Low Frequency Hydromagnetic Waves In The Magnetosphere, Vithalbhai Lallubhai Patel

Doctoral Dissertations

No abstract provided.

A Study Of The Kinetics Of The Unimolecular Reaction Between Nitrogen-Pentoxide And Nitrosyl Chloride, Nicholas Zevos

Doctoral Dissertations

No abstract provided.

A Study Of Ring-Chain Tautomerism In Ortho-Acylbenzoic Acids By Chemical And Spectral Methods, Peter John Desio

Doctoral Dissertations

No abstract provided.

Neutron Albedo Measurements On Polar-Orbiting Satellites, James Harold Trainor

Doctoral Dissertations

No abstract provided.

Studies On Potato Spindle Tuber Virus, James Edward Hunter

Doctoral Dissertations

No abstract provided.

A Study Of Turbulent Mass Transfer In A Wetted-Wall Column, David William Bunch

Doctoral Dissertations

"The field of mass transfer is one of great interest to the chemical engineer. An understanding of this field is vital in the design of many types of chemical processing equipment, particularly in the areas of distillation, extraction, absorption, adsorption, and reactor analysis and design.

However, much of the knowledge in this area at the present time is in the form of empirical relationships, and the basic theory is still not well delineated. This lack of understanding leads to expensive and over-sized or under-sized equipment.

A particular area within this field which needs additional investigation is the theory of mass …

The Origin Of The Bedded Arkansas Barite Deposits (With Special Reference To The Genetic Value Of Sedimentary Features In The Ore), Richard A. Zimmermann

Doctoral Dissertations

"The objective of this study has been to determine the geometric and mineralogic relationships existing between the barite and related sediments in the Stanley Shale in Arkansas and also to establish geometric, mineralogic, petrographic, and geochemical criteria for the interpretation of the origin of the barite and associated minerals. In addition, comparisons with German deposits have been made"--Introduction, Objective and Outline of Study, page [1].