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Articles 2941 - 2970 of 2977
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Dynamics Of Disordered Harmonic Lattices, Daniel N. Payton Iii
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 …
Diffusional Drop Growth In A Supersaturated Atmosphere, John C. Carstens
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.
A Theoretical Approach To The Problem Of Determining Ejecta Volumes In A Gravitational Vacuumed Half-Space, William J. Karwoski
A Theoretical Approach To The Problem Of Determining Ejecta Volumes In A Gravitational Vacuumed Half-Space, William J. Karwoski
Doctoral Dissertations
"The formation of an explosion crater is a highly complex process. All of the pertinent parameters governing the mechanisms of cratering are not clearly understood or known. Many cratering experiments were performed in desert alluvium in an effort to relate crater dimensions with charge weight and depth of burst. Various scaling laws were devised in an attempt to correlate the data gathered from these experiments. When cube-root scaling was used to correlate results of tests conducted at a constant scaled depth of burst, larger charge weights consistently gave smaller scaled results. This was particularly true of apparent crater volume. When …
The Statistical Mechanics Of Kink Interactions, Michael Brewer Mcneil
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
A Study Of (Deuteron,Proton) Reactions On Light Nuclei From 200 To 350 Kev, Joel Edward Henkel
Doctoral Dissertations
No abstract provided.
An Investigation Of Current Induced Mass Migration In Solid Metals, Steven Mitchell Kovel
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 …
Drag Reduction In Newtonian Polymer Solutions, Harry C. Hershey
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.
A Solution To Einstein's Gravitational Field Equation For A Spherically Symmetrical Static Perfect Fluid, Lionel Donnell Hewett
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 Introduction To Linear Time-Variant Digital Filtering Of Seismic Data, Richard Harold Lassley
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 …
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
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 …
Variation In Gold Content Of Minerals Of The Marysville Quartz Diorite Stock, Montana, Erwin Joseph Mantei
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 …
Pair Distribution For A Cell-Model Liquid, James M. Phillips
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 …
A Study Of Near Surface Elastic-Anelastic Layers, Charles Allen Aldrich
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
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 …
Low Frequency Hydromagnetic Waves In The Magnetosphere, Vithalbhai Lallubhai Patel
Low Frequency Hydromagnetic Waves In The Magnetosphere, Vithalbhai Lallubhai Patel
Doctoral Dissertations
No abstract provided.
A New Determination Of The Homogeneous Nucleation Rate Of Water In Helium, Edward Francis Allard
A New Determination Of The Homogeneous Nucleation Rate Of Water In Helium, Edward Francis Allard
Doctoral Dissertations
"The object of this investigation is to apply the best known cloud chamber techniques to the study of condensation phenomena, directed mainly toward the development of a precise method for the determination of homogeneous nucleation rates. A secondary object is to investigate the properties of re-evaporation nuclei so that adequate precautions may be taken to eliminate their detrimental effect in the homogeneous nucleation experiments"--Statement of Problem, page 10.
A Study Of Turbulent Mass Transfer In A Wetted-Wall Column, David William Bunch
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
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].
On The Kirkwood Superposition Approximation, Russell V. Cochran Jr.
On The Kirkwood Superposition Approximation, Russell V. Cochran Jr.
Doctoral Dissertations
"When the Kirkwood superposition approximation for the triplet distribution function is used in the Born-Green equation for the pair distribution function of a liquid, the fourth virial coefficient is given incorrectly. In view of this, two suggestions for improving the approximation have been investigated. A suggestion, due to G.H.A. Cole, that better results could be obtained by using a second-order integro-differential equation of the Born-Green type with the superposition approximation used for both the triplet and quadruplet distribution functions has been investigated, and results for a hard-sphere model show that this method gives considerably less reliable results than those obtained …
Petrology And Mineralogy Of Certain Portions Of The Fredericktown Deposits, Farouk El Baz
Petrology And Mineralogy Of Certain Portions Of The Fredericktown Deposits, Farouk El Baz
Doctoral Dissertations
"The Fredericktown area is part of the 'Lead Belt' district of southeastern Missouri, the major lead-producing region in the world for fifty years. The district is a typical example of the Mississippi Valley Type deposits. The ores occur in Upper Cambrian sediments overlying Precambrian rocks.
The Fe-Cu-Pb-Zn (-Co-Ni) - sulphide deposits of Fredericktown occur over a few square kilometers in sediments overlying two 'granite knobs'. The sedimentary units lap upon and pinch-out against these buried basement hills.
The basal sedimentary unit, the Lamotte Formation, is a time-transgressive, marine, submature orthoquartzite. It contains a Boulder Bed at the base or at …
A Study Of Plane And Spherical Compressional Waves In A Voigt Viscoelastic Medium, Gerald B. Rupert
A Study Of Plane And Spherical Compressional Waves In A Voigt Viscoelastic Medium, Gerald B. Rupert
Doctoral Dissertations
"In investigating the behavior of waves traveling through cohesive solids, two assumptions are usually made: that the propagating medium is either elastic or viscoelastic, and that the wave is either planar or spherical in form. For small distances from the source of the disturbance the medium can be considered elastic and the wave spherical rather than planar. The assumption of elasticity allows considerable simplification of the mathematical analysis, and assuming a spherical wave form is an acceptable approximation if the initial disturbance is essentially a point source and the propagating medium is nearly homogeneous. However, for large distances from the …
A Study Of The Eddy Diffusivity In Turbulent Heat Transfer, Frank Fu-Kun Tao
A Study Of The Eddy Diffusivity In Turbulent Heat Transfer, Frank Fu-Kun Tao
Doctoral Dissertations
"The purpose of this investigation was to determine the eddy thermal diffusivity values as a function of radial position at various Reynolds numbers for a fluid flowing turbulently in a pipe. The ratios of the eddy thermal diffusivity and the eddy viscosity were also investigated.
A vertical column of copper tube two inches in diameter was constructed which consisted of an entrance section for the development of the velocity profile and a heating section for the development of the temperature distribution. The heating section was jacketed and maintained at a constant wall temperature at about 103 ° F by the …
Lattice Parameters, Thermal Expansion Coefficients, Densities, And Imperfections In Silver And In The Alpha-Phase Of The Silver-Indium System, Samir Moustafa Riad
Lattice Parameters, Thermal Expansion Coefficients, Densities, And Imperfections In Silver And In The Alpha-Phase Of The Silver-Indium System, Samir Moustafa Riad
Doctoral Dissertations
“An investigation of structure insensitive properties (lattice parameters, thermal expansion coefficients, densities, and imperfections) of silver and the α-phase of the silver-indium system was suggested by the desirable uses for silver and its indium alloys.
Both silver and indium used were 99.999 per cent pure. The silver-indium alloys were prepared by melting both metals inside evacuated and sealed fused quartz tubes. The solidified alloys were annealed and then examined by X-ray diffraction for homogeneity.
This experimental work is divided into three main parts:-
I. X-ray diffraction investigation to determine the solid solubility limit of the Ag-In α-phase at 25° C, …
Stratigraphy Sedimentation And Petroleum Possibilities Of The Middle Ordovician (Kimmswick-Galena) Rocks Of Missouri, Illinois And Iowa, Krishna Kant Misra
Stratigraphy Sedimentation And Petroleum Possibilities Of The Middle Ordovician (Kimmswick-Galena) Rocks Of Missouri, Illinois And Iowa, Krishna Kant Misra
Doctoral Dissertations
"Detailed surface and subsurface studies of the Kimmswick Limestone and the Galena Formation of Middle Ordovician age in eastern Missouri, western Illinois, and southeastern Iowa were conducted in order to examine their stratigraphic relations, geological history, environment of deposition, and petroleum possibilities.
The main objective of this study was to seek a stratigraphic subdivision of the Kimmswick Limestone in Missouri, based on its gross lithology and thin section study, and its correlation with the Galena Formation in Illinois and Iowa. As a result of this study, based on the examination of twelve surface sections and 92 thin sections a three-fold …
Mineralogy, Petrography, And Ceramic Properties Of Lower Cabaniss Underclays In Western Missouri, Anthony C. Tennissen
Mineralogy, Petrography, And Ceramic Properties Of Lower Cabaniss Underclays In Western Missouri, Anthony C. Tennissen
Doctoral Dissertations
The mineral and chemical components, the petrography, and the ceramic properties of the Weir-Pittsburg, Tebo, and Mineral underclays In Barton, Vernon, St. Clair, sod Henry Counties of western Missouri have bean Investigated by x-ray diffraction, differential thermal, spectrographic, microscopic, and certain ceramic testing techniques. The underclays are composed principally of little, kaolinite, end mixed-layer illite-montmorillonite. Illite is the dominant mineral. The principal non-phyllosilicate minerals are quarts sad pyrite. The under clays are mineralogically similar to the underlying shales and contain clay pallets which also are mineralogically similar to the underclays and shales in which they are found. The clay appears …
Mineral Paragenesis And Trace Element Distribution In The Tri-State Zinc-Lead District Missouri, Kansas, Oklahoma, Richard D. Hagni
Mineral Paragenesis And Trace Element Distribution In The Tri-State Zinc-Lead District Missouri, Kansas, Oklahoma, Richard D. Hagni
Doctoral Dissertations
"A review of the literature pertaining to the mineral paragenesis and trace element distribution in the Tri-State zinc-lead district of Missouri, Kansas, and Oklahoma revealed inconsistencies in observation and in interpretation and divergent hypotheses regarding the origin of the ores. In an attempt to reconcile the data collected by many investigators over nearly three-quarters of a century, the writer observed working faces in 37 mines, collected over 2,000 specimens for binocular examination and prepared and studied 110 polished surfaces and 60 thin sections of the ores and associated rocks utilizing mineralographic, petrographic, and x-ray techniques. This detailed study resulted in …
Statistical Analysis Of Fracture Stresses Of Triaxial Porcelain Bodies, Robert E. Moore
Statistical Analysis Of Fracture Stresses Of Triaxial Porcelain Bodies, Robert E. Moore
Doctoral Dissertations
"Triaxial porcelain bodies containing various forms of silica, quartz, cristobalite and fused silica, were strength tested in bending. Significance tests were employed to discern real differences in the strength sample statistics caused by the various forms of silica. Firings were performed at three temperature levels. The differences in strength sample statistics were correlated to the microstructures of these silica porcelains.
A triaxial alumina porcelain body was employed as a model brittle solid for a study of the effect of flaw density on mean fracture stress. The flaws were introduced in the form of large diameter (d̄ = 115 microns) rounded …
The Geology Of The Eldorado Mining District, Clark County, Nevada, Spenst M. Hansen
The Geology Of The Eldorado Mining District, Clark County, Nevada, Spenst M. Hansen
Doctoral Dissertations
The rocks of the Eldorado mining district, Clark County, Nevada, are of Precambrian, Tertiary and Quaternary age. Precambrian rocks include a heterogeneous series of gneisses and schists, younger garnetiferous granite gneiss and a youngest group of pegmatites. Paleozoic and Mesozoic rocks present in surrounding areas are absent in the district and Tertiary volcanics lie directly on the Pre- cambrian basement. Tertiary rocks consist of middle to late Tertiary flows and pyroclastic beds of andesite, basalt and rhyolite. These are assigned to three volcanic formations: the Patsy Mine volcanics; the Golden Door volcanics; and the Mount Davis volcanics. The Patsy Mine …
Sorption And Diffusion In Polyvinyl Acetate And Other Linear Amorphous Polymers, Roger Peabody Kambour
Sorption And Diffusion In Polyvinyl Acetate And Other Linear Amorphous Polymers, Roger Peabody Kambour
Doctoral Dissertations
No abstract provided.
Some Physical, Chemical, And Thermohydrodynamic Parameters Of Explosive Ammonium Nitrate-Fuel Oil Mixtures, Joseph J. Yancik
Some Physical, Chemical, And Thermohydrodynamic Parameters Of Explosive Ammonium Nitrate-Fuel Oil Mixtures, Joseph J. Yancik
Doctoral Dissertations
"The explosive properties of ammonium nitrate-fuel blasting agents were investigated by measuring their detonation velocity and sensitivity. Detonation velocity was measured by a pin oscillograph method with a modified pin technique. Five types of tests were used to evaluate the explosive sensitivity of AN-fuel mixtures under varied environmental conditions. These tests measured the confined and unconfined critical diameter, minimum primer for a three inch diameter iron pipe confined charge, for an unconfined charge at the critical diameter, and minimum primacord primer under special conditions.
Properties of ammonium nitrate-fuel blasting agents were evaluated by considering the effects which each component of …