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Oxidation Of Tetragonal Pbo In Air, Charles A. Sorrell Jan 1973

Oxidation Of Tetragonal Pbo In Air, Charles A. Sorrell

Materials Science and Engineering Faculty Research & Creative Works

Isothermal oxidation of tetragonal PbO in air produced multiphase assemblages with apparent equilibrium compositions which varied linearly with temperature from PbO1.548 at 286°C to PbO1.333 at 351°C. Oxidation at each temperature was relatively rapid to PbO1.40 and very slow from PbO1.40 to apparent equilibrium values. Pseudocubic PbO1+x, with compositions between PbO1.41 and PbO1.57, was indexed on a cubic unit cell at the lower O/Pb ratios and on a tetragonal unit cell at the higher ratios. Linear changes in lattice parameters and deviation from cubic symmetry accompanied reversible oxidation and reduction of the phase. Pseudocubic PbO1+x was reduced irreversibly to Pb3O4 …


Stratigraphic Relations Of Members Of The Needles Range Formation At Type Localities In Southwestern Utah, M. G. Best, R. T. Shuey, C. F. Caskey, S. Kerry Grant Jan 1973

Stratigraphic Relations Of Members Of The Needles Range Formation At Type Localities In Southwestern Utah, M. G. Best, R. T. Shuey, C. F. Caskey, S. Kerry Grant

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Needles Range Formation is one of the most extensive of the middle Tertiary ash-flow sheets in the Great Basin of Nevada and western Utah. The original definition of the formation by Mackin (1960) named two members and mentioned three type localities. Our recent studies have shown that this published information now requires revision. To provide a firm basis for stratigraphic studies of the Needles Range Formation, this paper presents geologic maps, measured sections, and paleomagnetic data for three type localities in southwestern Utah. These include the northern Needles Range and Wah Wah Springs localities previously mentioned by Mackin, plus …


Conditioned Sampling Techniques, R. E. Kaplan Jan 1973

Conditioned Sampling Techniques, R. E. Kaplan

Symposia on Turbulence in Liquids

The concept of organized, spatially coherent large scale structures has been investigated for a variety of turbulent shear flows by a technique called "Conditional Sampling." It can be shown that these structures are related to physically important activities such as, 1) the entrainment of turbulent boundary layers, and 2) the maintenance of turbulence by a wall, 3) the growth of free shear layers, and 4) the structure and noise production of turbulent jets.

The general technique of conditioned sampling is related to visualizations of the flow, and to problems of synchronization of images in the presence of noise. While there …


Oxidation State Control Of Volatile Species In Sintering, P. D. Ownby Jan 1973

Oxidation State Control Of Volatile Species In Sintering, P. D. Ownby

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.


Polynary Silicon Arsenic Chalcogenide Glasses With High Softening Temperatures, H. E. Anthonis, N. J. Kreidl, W. H. Ratzenboeck Jan 1973

Polynary Silicon Arsenic Chalcogenide Glasses With High Softening Temperatures, H. E. Anthonis, N. J. Kreidl, W. H. Ratzenboeck

Materials Science and Engineering Faculty Research & Creative Works

The introduction of Ag in SiAsTe glasses permits the incorporation of Se, otherwise volatile and/or degradable as a constituent in Si-containing chalcogenide glasses. SiAsAgTeSe glasses exhibit much higher softening ranges and glass transition temperatures than encountered in known chalgogenide systems. A glass Si35As15Ag10Te20Se20 had the viscosity log ν = 13 at about 500°C, as compared to 370°C for the base glass Si35As25Te40, the viscosity of log ν = 9.8 at about 560°C, as compared to 442°C for the base glass. Phase separation occurs in the system SiAsAgTeSe and becomes manifest in two glass transitions indicated by changes in the slopes …


Compacted Cohesive Test Embankment: Design, Installation And Operation Of Field Instrumentation : Interim Report, Wiiliam L. Degroff Jan 1973

Compacted Cohesive Test Embankment: Design, Installation And Operation Of Field Instrumentation : Interim Report, Wiiliam L. Degroff

JTRP Technical Reports

No abstract provided.


Mechanical Behavior And Reinforcement Of Mineral Filler-Asphalt Mixtures : Technical Paper, David Albert Anderson, William Harner Goetz Jan 1973

Mechanical Behavior And Reinforcement Of Mineral Filler-Asphalt Mixtures : Technical Paper, David Albert Anderson, William Harner Goetz

JTRP Technical Reports

No abstract provided.


Effect Of Variations In Coarse Aggregate Gradation On Properties Of Portland Cement Concrete : Technical Paper, Charles F. Scholer, Stephen Daugherty Baker Jan 1973

Effect Of Variations In Coarse Aggregate Gradation On Properties Of Portland Cement Concrete : Technical Paper, Charles F. Scholer, Stephen Daugherty Baker

JTRP Technical Reports

No abstract provided.


Nitrogen Fixation By Woody Plant Species As Measured By Acetylene Reduction Assay : Technical Paper, Robert E. Mcniel, Philip L. Carpenter Jan 1973

Nitrogen Fixation By Woody Plant Species As Measured By Acetylene Reduction Assay : Technical Paper, Robert E. Mcniel, Philip L. Carpenter

JTRP Technical Reports

No abstract provided.


Use Of Shale In Embankments : Technical Paper, Purushottam Deo, Leonard E. Wood, C. W. Lovell Jan 1973

Use Of Shale In Embankments : Technical Paper, Purushottam Deo, Leonard E. Wood, C. W. Lovell

JTRP Technical Reports

No abstract provided.


Dynamic Modulus Of Bituminous Mixtures As Related To Asphalt Type, Larry L. Yeager Jan 1973

Dynamic Modulus Of Bituminous Mixtures As Related To Asphalt Type, Larry L. Yeager

JTRP Technical Reports

No abstract provided.


Determination Of Atterberg Limits Using Moisture Tension Methods : Technical Paper, Ahmed Atef Gadallah, Eugene Robert Russell, Eldon J. Yoder Jan 1973

Determination Of Atterberg Limits Using Moisture Tension Methods : Technical Paper, Ahmed Atef Gadallah, Eugene Robert Russell, Eldon J. Yoder

JTRP Technical Reports

No abstract provided.


Legendre Coefficients For Series Solution Of The Orientation Distribution Function For Ellipsoidal Macromolecules In Two-Dimensional Laminar Flow, Myrne R. Riley Jan 1973

Legendre Coefficients For Series Solution Of The Orientation Distribution Function For Ellipsoidal Macromolecules In Two-Dimensional Laminar Flow, Myrne R. Riley

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The double refraction and viscosity of a suspension of asymmetrical colloidal particles subject to continuous laminar flow vary with the orientation distribution of the suspended particles produced by the shearing field and Brownian motion. Recursion formulas are developed for the Legendre coefficients of the series solution of the orientation distribution function for a suspension subject to two-dimensional laminar flow, thus, extending the works of Peterlin, Wayland, and Scheraga. © 1973.


Performance Degradation Due To Specular Multipath Intersymbol Interference, G. H. Smith, David R. Cunningham, Rodger E. Ziemer Jan 1973

Performance Degradation Due To Specular Multipath Intersymbol Interference, G. H. Smith, David R. Cunningham, Rodger E. Ziemer

Electrical and Computer Engineering Faculty Research & Creative Works

Plots of performance degradation are used to compare the effects of fading and intersymbol interference in a two-component specular multipath digital communications channel. Similar plots are then used to compare two practical receivers designed to combat the interference. Degradation plots are shown to allow easy identification of each receiver's range of usefulness, as well as identification of variance bounds demanded of channel parameter estimates which the receivers require. Copyright © 1973 by The Institute of Electrical and Electronics Engineers, Inc.


An Improved Single Flight Technique For Radar Stereo, Gordon E. Carlson Jan 1973

An Improved Single Flight Technique For Radar Stereo, Gordon E. Carlson

Electrical and Computer Engineering Faculty Research & Creative Works

An improved technique for obtaining stereo radar image pairs is described. The technique uses a unique combination of two different radar beam pattern characteristics. The resulting stereo radar images are illuminated from very nearly the same aircraft position which results in radar shadow and back-scatter characteristics which are very similar and in improved image registration possibilities. The reduction in illumination angle and aircraft position differences is shown to be nearly an order of magnitude or more when compared with a previously proposed single flight technique which used two vertical fan beam patterns at different azimuth angles. As a related sidelight …


Breakdown Of The Laminar Flow Regime In Permeable-Walled Ducts, E. M. Sparrow, G. S. Beavers, T. S. Chen, J. R. Lloyd Jan 1973

Breakdown Of The Laminar Flow Regime In Permeable-Walled Ducts, E. M. Sparrow, G. S. Beavers, T. S. Chen, J. R. Lloyd

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The stability of laminar flow in a parallel-plate channel having one permeable bounding wall is investigated by means of linear theory. The analysis lakes account of the coupling of the disturbance, fields in the channel and in the permeable material and of velocity slip at the surface of the permeable wall. Complementary experiments are performed in which the breakdown of the laminar regime in flat rectangular ducts is identified from pressure-drop measurements and from flow visualization studies. The experiments cover the range of slip velocities from 15-30 percent of the mean velocity and, in addition, the case of zero slip …


Models Of Outdoor Recreational Travel, John A. Deacon, Jerry G. Pigman, Kenneth D. Kaltenbach, Robert C. Deen Jan 1973

Models Of Outdoor Recreational Travel, John A. Deacon, Jerry G. Pigman, Kenneth D. Kaltenbach, Robert C. Deen

Kentucky Transportation Center Research Report

The purpose of this investigation was to evaluate models of travel flow from population centers throughout the United States to outdoor recreational areas in Kentucky. Data were obtained by means of a license-plate, origin-destination survey at 160 sites within 42 recreational areas and by means of a continuous vehicle counting program at eight of these sites. Attempts to simulate distributed travel flows concentrated on various single-equation models, a cross-classification model, and gravity and intervening opportunities models. The cross-classification model was found to be an acceptable means for simulating and predicting outdoor recreational travel flows and was decidedly superior to the …


Diaphragm Braced Thin-Walled Open Sections And Design Of Wall Studs, Amir Simaan, Teoman Peköz Jan 1973

Diaphragm Braced Thin-Walled Open Sections And Design Of Wall Studs, Amir Simaan, Teoman Peköz

CCFSS Library (1939 - present)

INTRODUCTION Cold-formed steel wall studs generally are I, Z or channel shaped with or without stiffening lips, and with webs perpendicular to the plane of the wall. Because of their configuration and dimensions, these sections are quite unstable by themselves. However, the stability and, hence, load-carrying capacity of such studs are increased substantially once they are connected to the wallboard material. The main function of the wallboard is that of enclosure, but it serves also as a bracing system for the studs. Gypsum board, vegetable fiberboard, tempered board or plywood are commonly used wallboard materials. Such boards are connected to …


Tilt-Table Alignment For Inertial-Platform Maintenance Without A Surveyed Site, Gordon E. Carlson, Max E. Bott Jan 1973

Tilt-Table Alignment For Inertial-Platform Maintenance Without A Surveyed Site, Gordon E. Carlson, Max E. Bott

Electrical and Computer Engineering Faculty Research & Creative Works

A method for aligning the rotary tilt table for an inertial-platform maintenance facility without surveying the site is analyzed and evaluated. The method utilizes multiple measurements of the tilt-table azimuth alignment error with different inertial platforms to determine a best estimate of the alignment error. Error analysis indicates that useful facility performance can be obtained with only a small number of measurements. The tilt-table alignment accuracy can be improved as more measurements of the alignment error are made during normal facility operation. © 1973, IEEE. All rights reserved.


Transient State Analysis Of Separated Flow Around A Sphere, Ching-Liang Lin Jan 1973

Transient State Analysis Of Separated Flow Around A Sphere, Ching-Liang Lin

Doctoral Dissertations

"Transient state solution of the Navier Stokes equation was obtained for incompressible flow around a sphere accelerating from zero initial velocity to its terminal free falling velocity. By assuming rotational symmetry around the axis in the falling direction, the Navier Stokes equation and the continuity equation were simplified in terms of vorticity and stream function. The instantaneous acceleration of the falling sphere was calculated by considering the difference between the gravitational force and the drag force in a transient state. The governing partial differential equations were non-dimensionalized. A set of implicit finite difference equations was developed. In order to obtain …


Premartensitic Elasticity Of Fe-Ni Invars, Bryce Linn Shriver Jan 1973

Premartensitic Elasticity Of Fe-Ni Invars, Bryce Linn Shriver

Doctoral Dissertations

"The premartensitic temperature dependence of ultrasonic wave propagation in Fe-30 pct Ni polycrystals and Fe-32 pct Ni single crystals was measured by using a continuous wave technique. As the temperature was lowered to within 10°C of the Ms, a nonlinear decrease of the relative shear velocity was observed. This effect is related to dislocation stacking fault instabilities which may trigger the martensitic phase transformation. In addition, the single crystals show a frequency dependence of the shear elastic constant C' well above the Ms. The dispersion is believed to be caused by fluctuations in the anisotropic molecular …


Nucleate Pool Boiling Of Refrigerant-Oil Mixtures From Tubes, R. L. Dougherty Jan 1973

Nucleate Pool Boiling Of Refrigerant-Oil Mixtures From Tubes, R. L. Dougherty

Masters Theses

"This experimental investigation was conducted to provide design heat transfer data for applications involving the nucleate pool boiling of Refrigerants 11 and 113 from the external surfaces of tubes. Tests were conducted with 0.625-in. o.d. and 1.125-in. o.d. commercial copper tubing; at 1 and 2 atmospheres pressure; and with refrigerant-oil compositions from 0 to 10 percent oil by weight. Results show that each of these parameters can affect the heat transfer coefficient"--Abstract, page ii.


A Suboptimal Control Law For Parametrically Disturbed Linear Systems And Its Application To Improve The Transient Stability Of Power Systems, Atluri Bhima Ranjit Kumar Jan 1973

A Suboptimal Control Law For Parametrically Disturbed Linear Systems And Its Application To Improve The Transient Stability Of Power Systems, Atluri Bhima Ranjit Kumar

Masters Theses

Paper 1: “A suboptimal linear control law is synthesized for parametrically disturbed linear systems, and the necessary approximation for applying the law to a class of nonlinear systems is given. The law is then extended to linear systems with stochastically disturbed parameters by using appropriate approximations”—Abstract, page 2.

Paper 2: “The application of optimal control theory to damp the electromechanical oscillations associated with the transient conditions in power systems has been given little attention. A suboptimal control law which minimizes the sum of the performance indices of the two linear systems given by a piecewise linear model of a power …


Design Of A High Pressure Fluid Intensifier, James Andrew Kwiatkowski Jan 1973

Design Of A High Pressure Fluid Intensifier, James Andrew Kwiatkowski

Masters Theses

"In this thesis the design of the major components of a high pressure intensifier is presented. The machine is a high pressure fluid intensifier which can develop an intermittent water jet of .01112 inches in diameter at a pressure of 100,000 psi and a flow rate of .9508 gpm. This machine can be used to study the capabilities of high pressure water jets to cut high compressive strength rocks.

The primary machine elements of the intensifier system are the source, charging system, valve system, nozzle, and the intensifier. The source will be a Kobe Triplex Pump having a variable output …


The Static Nonequilibrium Characteristics Of Planar Germanium Probes In A Slightly Ionized Hydrogen Plasma For Low Injections, Alfred Gene Williams Jan 1973

The Static Nonequilibrium Characteristics Of Planar Germanium Probes In A Slightly Ionized Hydrogen Plasma For Low Injections, Alfred Gene Williams

Masters Theses

"The theory for a planar semiconductor probe in a slightly ionized gas with small dc current densities is developed for a germanium probe immersed in a hydrogen plasma. First, the equilibrium characteristics due to the probe in the plasma are developed from Poisson's equation and current density equations. Then, the static nonequilibrium characteristics due to the probe are found by perturbing the equilibrium characteristics and substituting the perturbation terms into Poisson's equation and current density equations. The total current, I, is found to vary linearly with the applied voltages, V, and the ratios I/V are essentially the same for both …


Stability Of Filled Cylindrical Shell Columns, Yu Wen Tsao Jan 1973

Stability Of Filled Cylindrical Shell Columns, Yu Wen Tsao

Masters Theses

"This experimental investigation was conducted to study the stability of filled cylindrical shell columns. Two kinds of filler materials, flower clay (florist clay) and silica sand, were investigated. The cylindrical shells were made of 2024-T3 Reynolds aluminum tubing. Uniaxial compressive loading was applied directly to the filler materials through two loading rams, one at each end of the cylinder, (no loading was applied directly to the shell). Tests for investigating the load transmitting characteristics of the filler materials were performed, and the states of the stresses existing in the cylindrical shells were then obtained.

The buckling formula for thin-walled cylindrical …


A Digital Simulation Of A Single Articulated Rotor Helicopter, Joseph William Klahs Jr. Jan 1973

A Digital Simulation Of A Single Articulated Rotor Helicopter, Joseph William Klahs Jr.

Masters Theses

"The investigation was concerned with the development of a complete digital computer simulation of a single articulated rotor helicopter. The simulation program was executed on an IBM model 360-50 digital computer.

The main rotor was analyzed by the consideration of a continuous rigid blade at six azimuth stations, while the airframe aerodynamics were treated in the conventional manner. The differential equations of motion of the airframe were solved in a step-wise fashion by approximating time dependent functions with cubic interpolation polynomials.

The study concluded that there was strong evidence that suggested the possibility of treating main rotor flapping as a …


A Study Of Rf Induction Heating And Float Zone Refining Of Silicon, John Allen Reynolds Jan 1973

A Study Of Rf Induction Heating And Float Zone Refining Of Silicon, John Allen Reynolds

Masters Theses

"Float zone refining using simultaneous RF induction heating and electromagnetic levitation has proven to be the best technique for producing high purity silicon for the semiconductor industry.

A study of the power requirements for floating molten zones, of load to source impedance matching, and of considerations for RF heating coil design was conducted to determine possible methods of improving the technique. It is shown that the power requirements are within reason, that impedance matching can be improved by varying network parameters, and that certain vital items must be assured in the design of different RF heating coils.

It is believed …


A Pavement Design Schema, James H. Havens, Robert C. Deen, Herbert F. Southgate Dec 1972

A Pavement Design Schema, James H. Havens, Robert C. Deen, Herbert F. Southgate

Kentucky Transportation Center Research Report

Elastic theory and 40 years of empirical flexible pavement design in Kentucky have been joined into the design system presented herein. A brief discussion is presented of the coupling mechanisms relating experience to theoretical analyses. An annotated design procedure is presented as a guide for pavement designers. Design nomographs account for a wide range of input parameters and permit the designer a wide choice of alternative thickness designs.


Conference System User's Guide, Rod L. Renner, United States. General Services Administration. Office Of Preparedness. Mathematics And Computation Laboratory. Nov 1972

Conference System User's Guide, Rod L. Renner, United States. General Services Administration. Office Of Preparedness. Mathematics And Computation Laboratory.

Computerized Conferencing and Communications Center Reports

This paper describes three methods of group communication utilizing computer terminals as the vehicle for conducting a group discussion. The system that provides; these methods was developed by OEP for a UNIVAC 1108 as a convenient form of communication among geographically dispersed individuals and/or as an adjunct to oral communications. Completely normal language is used. Use of the computer permits maintaining a written record automatically and allowing discussions in which participants need not talk and listen in synchronism (in contrast to conventional meetings and telephone conference calls). In two of the methods, the discussants need not even be participating simultaneously. …