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Concrete In Dairies, D Roger Buchanan

Journal of the Department of Agriculture, Western Australia, Series 4

PRIME requirements for exposed concrete surfaces in dairies are that they should be easily cleansed and should not deteriorate in contact with milk and milk products.

In milking stalls, animal races and on loading platforms hardwearing surfaces which offer good foothold are also necessary.

Investigation By Neutron Diffraction Utilizing White Neutron Radiation, Arlen Ray Schade

Doctoral Dissertations

"The most probable reactor core neutron velocity was determined by analysis of data obtained from single crystals of copper and lithium fluoride. Derivation of the relationship between the maximum in experimental count rate and the most probable velocity, an error analysis of the method, and the computer routine are given for the method used to obtain the most probable velocity. The most probable velocity was used to index the maxwellian distributions from polycrystalline materials. Investigations were done with white neutron radiation of various silicon steel samples of different preferred orientation. A method is described by which the preferred orientation of …

Liquid Extraction With Single Droplets-Effect Of Chemical Reaction, William Victor Andoe

Doctoral Dissertations

"The circulating drop mass transport model based on Hadamard's dispersed phase stream function was solved numerically to account for a solute diffusing into a droplet and undergoing a first order irreversible reaction with the drop medium for the case where the continuous phase resistance to solute transport is negligible ... Experimental data were obtained for a system which consisted of 2-chloro-2-methylpropane (t-butyl chloride) diffusing from a benzene continuous phase into falling water droplets and undergoing a first order irreversible reaction with the water droplets ... The experimental solute transport rates were a factor of 7 to 10 greater than those …

Nonparametric Sequential Detection, James Charles Fowler

Doctoral Dissertations

"This dissertation extends the theory of the Wilcoxon-Mann-Whitney U statistic so that this statistic can be used to perform sequential tests on hypotheses. This sequential test procedure makes use of a sequential ranking procedure similar to the one first introduced by Parent. The operating-characteristic function and average number of samples function for this new test are calculated as a function of the signal to noise ratio. The test is then shown to be efficient for several forms of alternatives with an efficiency of 95% against the Wald Sequential Probability Ratio Test for a constant signal in normal noise. Finally, the …

Prediction Of Drag Reduction With A Viscoelastic Model, Gary Kent Patterson, J. L. Zakin

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

Influence Of Continuous Precipitation Upon The Growth Kinetics Of The Cellular Reaction In An Al-Ag Alloy, H. I. Aaronson, J. B. Clark

Materials Science and Engineering Faculty Research & Creative Works

The influence of the prior formation of a continuous precipitate upon the growth kinetics of the cellular reaction has been evaluated in an Al-17.9 wt. % Ag alloy. The continuous precipitate, in the form of intragranular plates of the γ′ transition phase, was shown to have reduced the upper bound of the driving force for the cellular reaction from the silver content of the untransformed alloy to that corresponding to the coherent solvus. When this reduction (≥ 98 %) is taken into account, the growth of cells is found to be controlled by cell boundary rather than by volume diffusion …

Age Hardening In A Mg-9 Wt.% Al Alloy, J. Beverley Clark

Materials Science and Engineering Faculty Research & Creative Works

The precipitation process and age hardening mechanism in a Mg-9 wt.% Al alloy were studied principally by transmission electron microscopy. This alloy age hardens by the general precipitation of plates of the equilibrium Mg₁₇Al₁₂ phase on the basal plane of the magnesium solid solution matrix. No evidence for the formation of either G.P. zones or a transition lattice of the Mg₁₇Al₁₂ precipitate was obtained. Cellular precipitation occurs competitively with the general precipitation at nearly all age hardening temperatures. In the solution treated condition, basal slip and {101̄2} twins are the principal deformation modes. Precipitation …

Interstitial Solute Trapping In Irradiated And Quenched Iron, M. (Manfred) Wuttig, J. T. Stanley, H. K. Birnbaum

Materials Science and Engineering Faculty Research & Creative Works

The interaction of interstitial carbon and nitrogen solutes with defects produced by low temperature neutron irradiation and by quenching was studied in high purity and Ferrovac E iron. Magnetic Dis accommodation techniques were applied to determine the interstitial solute content after irradiation and upon annealing. Doses of about 1017 neutrons/cm2 caused the trapping of about 20 ppm (atomic) interstitial solutes at 65 (carbon) and 40°C (nitrogen). Trapping of carbon in a Ferrovac E iron alloy occurred during a fast quench from 880°C. After trapping, the interstitial solutes reappeared in solid solution at 300 (carbon, neutron irradiation), 200 (nitrogen, neutron irradiation), …

Current Density-Anodic Potential Curves Of Single Crystal Gaas At Low Currents In Koh, Martin E. Straumanis, J. P. Krumme, William Joseph James

Materials Science and Engineering Faculty Research & Creative Works

Single p-type, GaAs crystals of high purity, Zn doped, were used to determine whether or not the inverse octahedral {111} faces show potential differences and various rates of anodic dissolution. The Ga{111}, As{111}, {110}, and {100} faces, were polished, etched, and etch-polished with concentrated H₂SO₄ + H₂O₂, and immersed in IN KOH. The Ga{111} faces were found to be the most noble with respect to rest and anodic dissolution potentials. The potential difference between the inverse {111} faces was as large as 0.14v for the rest and 0.123v for the dissolution potentials. The …

A Metallographic Study Of Solidification And Segregation In Cast Aluminum-Uranium Alloys, Bruce L. Bramfitt, Hollis P. Leighly

Materials Science and Engineering Faculty Research & Creative Works

The micromorphology and type of segregation in vacuum-cast ingots of aluminum-uranium alloys, ranging from 5 to 30 weight percent, were studied. The microstructural characteristics are similar to those of aluminum-silicon alloys of the same composition range, except that the aluminum-uranium eutectic was identified as having "chevron" and "rhombic spiral" types of morphology. © 1968.

Cutting Nbs Budget, Norbert J. Kreidl

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

Engineering Properties Of Bloomington-Normal Subsoils, Rohn Dunseth Abbott

Masters Theses

"The glacial subsoils of the Bloomington-Normal, Illinois area have been analyzed with regard to their engineering properties. Several boring logs are included to illustrate the horizontal and vertical variability in soil units encountered and in the engineering properties of these soil units. The engineering properties of the two most common foundation soils, the Bloomington and Normal tills are compared and special consideration is given to evaluating the compressibility of these materials. Evidence is presented that indicates that the circumferential trimming of a highly preconsolidated soil containing stones can cause significant sample disturbance. Special sampling techniques which eliminate circumferential trimming yield …

A Numerical (Matrix) Solution For The Vibration Frequencies And Modes Of A Nonuniform Rectangular Plate With Arbitrary Edge Conditions, F. David Utterback

Masters Theses

"The material presented in this thesis is designed to provide the practicing engineer with a practical, approximate method of solution for the increasingly important problem of plate vibrations. The technique presented herein is basically an application of the use of generalized coordinates to describe the elastic and inertial properties of a finite element representation of a nonuniform rectangular plate. The plate will be idealized by utilizing a modification of the grid work technique developed by Hrennifkoff as a lattice work of interconnecting beams. By employing the elastic displacements as generalized coordinates, the only required compatibility conditions are that the displacements …

An Experimental Method Of Determining The Thermal Accommodation Coefficients Of Metallic Surfaces, Raymond John Dethorne

Masters Theses

"In the free molecule regime, Knudsen number greater than 10, heat is transferred from a solid by radiation and conduction. The ability of a surface to emit radiant energy is governed by a surface property called emittance while the surface property which apparently regulates the amount of heat transferred by conduction is called the thermal accommodation coefficient. This thesis presents the results of an experimental investigation to determine a relationship between these two properties, emittance and thermal accommodation coefficient. A test apparatus was constructed to measure both the radiation and conduction contributions between two concentric cylinders. cylinders of aluminum and …

Fast Neutron Induced Resistivity Changes In Order-Disorder Fe₃Al, Bruce A. Betts

Masters Theses

"Resistivity measurements were made of ordered, disordered and intermediate states of order-disordered specimens of Fe₃Al while being irradiated by neutrons. All the specimens were irradiated at ambient temperature, approximately 35°C in a modified Bulk Shielding Swimming Pool type reactor. The ordered and near ordered specimens increased in resistivity indicating disordering whereas the disordered and near disordered specimens decreased in resistivity indicating an ordering process was occuring [sic]. By extrapolation, an equilibrium condition was determined and estimated at 130-135 micro-ohms-cm resistivity that would remain constant during irradiation because the ordering and disordering affects of neutron irradiation would be in equilibrium"--Abstract, page …

Influence Of Nobler Metal Salt Additions Upon The Dissolution Rate Of Aluminum In Hydrofluoric Acid, Barry L. Basden

Masters Theses

"The rate of dissolution of aluminum in 2N HF upon the addition of nobler metallic salts was studied. Aluminum corrodes in HF due to the acid's ability to dissolve the protective oxide present on the surface. Rates were measured by the hydrogen evolution method. Salt additions of AgN0₃, CuSO₄, HAuC₄, and PtCl₄ to aluminum dissolving in 2N HF resulted in the electroless deposition of more or less coherent metals (from the salts mentioned) on the aluminum surface. The dissolution rate initially decreased in all of the cases and was attributed to the "blanketing effect" of the deposits. Ensuing increases of …

Distillation Column Simulation And Control, Hsian T. Chao

Masters Theses

"A 5-component, 10-stage distillation column was simulated by PACTOLUS by use of the hybrid technique. It was found that the digital-analog simulator is completely satisfactory for solving unsteady-state multicomponent distillation problems. A feedforward controller for a distillation column was designed and tested. The effects of feedforward and feedback control on binary system distillation columns were compared by PACTOLUS. It was found that the liquid flow rates, the holdups as well as the number of stages are important factors in the design of a feedforward controller"--Abstract, page ii.

Diffusion Coefficients Of D-Glucose In Aqueous Carboxymethylcellulose And Carboxypolymethylene Solutions, Audrey Liu-Mei Huang

Masters Theses

"A microinterferometric method was used to determine the concentration profiles in the infinite field unsteady state diffusion of D-Glucose in aqueous polymer solutions. Pseudo binary diffusion coefficients were determined as a function of reduced concentration both with and without the effect of liquid volume change during diffusion being considered. The systems studied were D-Glucose in aqueous Carboxymethylcellulose and D-Glucose in aqueous Carboxypolymethylene solutions. Solute concentration ranged from nearly zero to about 9% by weight D-Glucose in the aqueous polymer solutions"--Abstract, page ii.

Scattering Parameter Measurements And Amplifier Design, Thomas J. Herrick

Masters Theses

"The scattering parameter formulation in describing the small-signal operation of an active two-port device is developed. The inherent advantages of measuring the scattering parameters at UHF frequencies and the clear insight into the design problem are demonstrated. Some of the practical difficulties in a typical design problem are also considered"--Abstract, page ii.

The Inert Gas Effect On The Rate Of Evaporation Of Zinc And Cadmium, Chu Sheng Wu

Masters Theses

"An experimental study has been made to investigate the effect of argon and helium on the rate of evaporation of zinc and cadmium under one atmosphere pressure at temperatures ranging from 500⁰C to 850⁰C. The experimental results were compared with the maximum rates calculated using the effusion formula as well as with values obtained using three different types of equations based on kinetic theory, diffusion theory, and empirical data. The rate of evaporation in this study appeared to be diffusion controlled. Equations have been derived for expressing the rate of evaporation of zinc and cadmium in both argon and helium …

Numerical Integration Of Shell Equations Using The Field Method, Pravin R. Ghael

Masters Theses

"In this work field equations are introduced to numerically solve the six linear differential equations which determine the displacements and stress resultants for thin elastic shells with axially symmetric loadings. With the applications of the field equations to the analysis of symmetric shells, the two-point boundary-value problem is formulated in terms of twelve first-order ordinary differential equations with boundary conditions at only one point. These equations are solved by using a forth [sic]-order Runge_kutta integration formula. Three problems whose solutions are known have been evaluated to check the accuracy of the field equation method. These are: (1.) Simply-supported, thin circular …

Isotope Effect Of Interstitial Diffusion Of Carbon In A Dilute Fe-Si Alloy, Edward T. Yen

Masters Theses

"The isotope effect of carbon interstitial diffusion in a Fe-2.75at%Si alloy has been measured at -3.10°C using the disaccommodation technique. The disaccommodation has been analyzed in terms of two relaxation processes which are discussed on the basis of the reorientation mechanism of carbon interstitials at Fe-Fe sites and Fe-Si sites respectively. The ratios of the relaxation times [tau]₁₃/[tau]₁₂ are 1.0382 for the former and 1.0072 for the latter relaxation process. This result is discussed on the basis of many-body reaction rate theory"--Abstract, page ii.

Specification For The Design Of Cold-Formed Steel Structural Members, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

A Numerical Simulation Of Pressure Distribution And Radius Of Drainage In Infinite Radial Aquifers - Constant Rate Case, Alton John Nute

Doctoral Dissertations

"The diffusivity equation for the transient flow of slightly-compressible liquids has been solved for infinite radial aquifers, subject to constant terminal rates, by employing a Romberg integration of the Van Everdingen - Hurst explicitly solution over the transformed integral limits for .01̲TD>500, the classical solutions presented by Carslaw and Jaeger, Mortada, Theis, and others are incorporated in the digital analysis to yield dimensionless pressures for 40 selected dimensionless radius (RD) ratios between 1 and 64 for dimensionless time values of .0005 to 1000.0. A new expression for dimensionless pressure-distribution, PD'(RD, TD), as a fraction of well bore pressure drop …

Distributed Parameter Rc Network Analysis, Robert C. Peirson

Doctoral Dissertations

"Methods of analyzing uniform and tapered distribute [sic] parameter RC networks are reviewed and correlated in this dissertation. Multilayer networks and simple three layer networks are considered. Analogies between two-wire transmission line theory and multilayer distributed network theory are developed, i.e., standing wave and traveling wave concepts. An accurate computer-aided steady state analysis procedure is presented which has a solution accuracy that can be determined prior to actual analysis computations. The impulsive response of the uniform RC network is investigated with the goal of measuring the network's parameters. Procedures to determine the parameters R and C of a uniform RC …

Surface Self-Diffusion On Nickel (111) By Radioactive Tracers, James Ronald Wolfe

Doctoral Dissertations

"Surface self-diffusion coefficients have been measured by a radioactive tracer method over the temperature range 614⁰ to 840⁰C on nickel (111) surfaces characterized by LEED. Previously unrecognized tracer evaporation during surface diffusion resulted in restricted spreading of the tracer at higher temperatures. A theoretical treatment of the tracer evaporation phenomenon is presented and subsequently used in the analysis of the data. The temperature dependence of the surface self-diffusion coefficient (D_s) for nickel (111) can be represented, over the experimental temperature range, by a single Arrhenius type relationship...Arguments are presented to justify an adatom surface diffusion mechanism which is …

The Identification And Evaluation Of Toxic Effects Of Organic Micropollutants, John Warren Smith

Doctoral Dissertations

No abstract provided.

Semiempirical Determination Of The Differential Fast Flux Spectrum For U-235 Fission With Water Moderator, Henry Anthony Till

Masters Theses

"The differential fast flux spectrum of the UMR Pool Research and Training Reactor core was determined by simultaneous activations of threshold foil detectors by neutron-nucleon reactions. This represents one phase of the composite neutron environment at two sample irradiation locations and the center of a fuel element during a power operation of 200 Kw (th). To accomplish this measurement a semiempirical least-squares approximation fitting activation date to a theoretical Cranberg U-wet fission spectrum was applied. This is a technique designed specifically for water moderated systems and takes into consideration both virgin and down-scatter neutrons. Gamma decay photopeaks were reduced using …

Transient Response Of A Class Of Distributed Systems, Jaw-Shyong Tzeng

Masters Theses

"The transient response of uniform distributed systems with any transfer function that is rational in w=e[square root of Ts] can be analyzed with the basic form of the transfer function [1 over (w-a)] after partial fraction expansion, where the pole a can be real or complex in the w plane. with the complex pole within the stable region in the w plane, there are only two possible combinations of the basic transfer function [1 over (w-a)], i.e. [1 over (w-a)] ł [1 over (w-a*)], for physical realizability. The imaginary part of the transient response of the basic transfer function [1 …

A Simple Design Algorithm For Synthesis Of Multilevel Combinational Networks, James H. Tracey

Electrical and Computer Engineering Faculty Research & Creative Works

An algorithm is presented for the synthesis of combinational networks with a constrained arrangement of ANDS, ORS, NANDS, NORS, and inverters. The algorithm is easily presented to students in an introductory logic design course and has considerable application in modern practical logic design. Many texts available for a first course in logic design give very limited practical guidance for synthesis of networks under constraints outlined here. It is suggested that the algorithm presented here be furnished as supplementary material in the introductory course. Copyright © 1968 by The Institute of Electrical and Electronics Engineers, Inc.