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Laboratory Studies Using Diffused Oxygen And Air For Hypolimnion Reaeration, Chin-Ming Pai

Masters Theses

"The purposes of this research were to study the oxygen transfer rates and the oxygen transfer efficiencies of different types of aerators using different sources of oxygen in different types of water bodies, and to evaluate the number of diffusers required to be installed in a selected lake for hypolimnion aeration.

The experiments were conducted using a specially designed column. Four types of aerators, including a cylindrical stone diffuser, a spherical stone diffuser, and 2 ceramic diffusers (types A and B) which differed in pore size, were utilized as the aerators. The water bodies selected for the studies were Rolla …

The Morphology Of The Cellular Precipitation Reaction In A Pb-3.0 Wt% Sn Alloy, Federico Sequeda Osorio

Masters Theses

"The complete development of the cellular precipitation structure at selected grain boundaries in a Pb-3.0 wt% Sn alloy during aging at 34°C and 23°C was investigated by light microscopy. The cellular structure in this alloy consists of lamellae of solute depleted lead solid solution and lamellae of ß tin precipitate. The cellular precipitation reaction begins by local migration of a grain boundary with concomitant grain boundary precipitation of ß tin. The grain boundary bows around the ß tin grain boundary precipitates which then begin to lengthen in the direction of boundary migration thus forming the precipitate lamellae of the cell. …

Polynary Silicon Tellurium Glasses, Henry Edward Anthonis

Masters Theses

"The introduction of Ag into Si-As-Te glasses permits the incorporation of Se, otherwise volatile and/or degradable as a constituent in Si-containing chalcogenide glasses. Si-As-Ag-Te-Se glasses exhibit much higher softening ranges and glass transition temperatures than encountered in known chalcogenide systems. A glass Si₃₅As₁₅Ag₁₀Te₂₀Se₂₀ had the viscosity log η =13 at about 500°C, as compared to 370°C for the base glass Si₃₅As₂₅Te₄₀, the viscosity of log η = 9.8 at about 560°C, as compared to 442°C for the base glass Si₃₅As₂₅Te_{40 …}

Effect Of Glass Aggregates Upon Abrasiveness Of Asphaltic Mixtures, Dwarka Prasad Gupta

Masters Theses

"The utilization of glass as an aggregate in asphaltic concrete pavements has been suggested as a means for reusing the increasing amounts of waste glass generated each year in the United States. Recent studies have shown that asphaltic mixtures containing glass aggregates can be designed to meet Marshall requirements for stability, flow and void content but the abrasiveness of mixtures containing glass aggregates had not been investigated. The objectives of this study were to develop a laboratory wear testing apparatus and compare the abrasiveness of asphaltic concrete mixtures using glass aggregates with the abrasiveness of mixtures using several different conventional …

Design And Construction Of A Drop Generator For Use In A Vertical Wind Tunnel, Danny Ray Conner

Masters Theses

"A drop generator, based on the principle of a vibrating capillary, was designed and built for use in the UMR vertical atmosphere wind tunnel. The drop generator worked very well on a test stand where it was firmly supported, but was not consistent when tested in the wind tunnel. Vibration of the wind tunnel walls and a slight turbulence near the forward edge of the generator caused an oscillation in the position of the stream of drops. The oscillation resulted in some of the drops hitting the edge of the collector cup, where the drops would accumulate until a large …

Computer Simulation Of The Primary Recoil Spectra And Damage Cross Section Of Fe₃Al Using Endf/B Ii Data, Daniel Willard Smith

Masters Theses

"A computer program, using Evaluated Nuclear Data File (ENDF/B II) information, was used to develop energy-exchange kernels which delineate the energy transfer probabilities between neutrons and Fe₃Al lattice atoms. The kernels combine all available information on elastic and inelastic scattering contained in the ENDF/B II data.

The computer program used to generate the primary recoil spectra is SAKI, a modified version of RICE (1). SAKI is designed to calculate energy-exchange probabilities in any binary alloy as well as damage cross sections and optimum cutoff energies for use in comparing displacement effects in different reactor spectra."--Abstract, page ii.

Design Of A Torsional Vibration Machine, Prafulchandra Pragjibhai Desai

Masters Theses

"In this thesis the design of the major components of a torsional vibration machine is presented. The machine is a torsional vibration actuator which will deliver a mean output angular velocity with a superimposed harmonic component. This type of motion can be used to study the torsional vibration characteristics of models representing crankshafts, gear trains, torsional dampers, and other systems. The primary machine elements of the actuator are a power source, flywheel, and a Hooke's joint. The power source consists of a D.C. shunt motor and a drive transmission using 3 V-belts. Through the use of a Hooke's joint, approximate …

Equilibria Between Moo₂ And Liquid Molybdenum Oxide, Prakash Bakhru

Masters Theses

"The oxygen pressure over solid molybdenum dioxide in equilibrium with liquid molybdenum oxide was determined by transpiration and solid electrolytic galvanic cell methods at 950ºC and 900º, 950º and 1000ºC respectively. The results were compared to those expected from thermodynamic data on the Mo-O system. Possible reactions between MoO₂ and SiO₂ were studied at different oxygen pressures up to 1550ºC. No compound formation or solid solution between MoO₂ and SiO₂ was detected by x-ray diffraction techniques. The phase boundary between MoO₂ and liquid molybdenum oxide was checked by microscopic examination of quenched samples. Equilibration runs were carried out in silica …

Calculation Of Buildup Factors For Multilayer Slab Shields Using The Monte Carlo Method, John Paul Kuspa

Masters Theses

"Gamma-ray beams normally incident upon slab shields of varying compositions are studied using a computer program based upon the Monte Carlo technique. Initial gamma energies of 1, 4, 6, and 8 MeV are considered. The shielding materials used were aluminum, iron, and lead. Both single and double material shields were investigated, at a variety of thicknesses up to a maximum of five mean free paths. Two secondary gamma processes are included in this simulation: annihilation gammas from pair production and bremsstrahlung from the electrons. The primary effort is the calculation of the dose, energy, and number buildup factors for these …

The Effects Of Intense Sound Levels And Steady Flow On The Propagation Of Plane-Waves In Air, Wuu Hao

Masters Theses

"This thesis is a theoretical investigation of the effects of intense sound levels and steady flow on the propagation of plane-waves in tubes of constant diameter. The analysis is limited to a study of the change of wave profile due to the intense sound levels, and steady flow. However, corrections for effects of viscous and heat conduction losses at tube walls are also presented. To simplify the analysis, the problem is treated by considering the steady flow and finite-amplitude-sound wave effects separately. For finite-amplitude sound only, two approaches are evaluated. The first uses small perturbations to derive a finite-amplitude wave …

Effect Of Biological Activity On Pesticide Desorption, Loh-Tien Chiang

Masters Theses

"The purpose of this research study was to investigate the effect of biological activities on the desorption of pesticides from humic acid solids. The pesticides selected in this study are dieldrin and heptachlor, both of which have been commonly used in agricultural applications. The humic acid adsorbent was extracted from a coal-like substance called "leonardite", which has a humus content of as high as 53 percent by weight. The first step of this study involved a proper cultivation of biological culture so that the culture could be adapted to a test environment containing a high concentration of humic acids. The …

A Comparison Of Analytical And Experimental Approaches In Determining The Thermoelastic Stresses Around A Cylindrical Inclusion Of Elliptical Cross-Section, Kenneth Byron Oster

Masters Theses

"Three approaches are used to determine the principal stress differences in an infinite elastic medium containing a cylindrical inclusion of elliptic cross-section due to a uniform temperature change. First, the two-dimensional equations of thermoelasticity are solved resulting in equations for the stress components anywhere in the medium material. Second, boundary displacements based on stress-strain relations are used as input displacements in a finite element program of the medium. Third, these same boundary displacements are used as input displacements on a photoelastic model simulating the medium. The problem is treated as one of plane strain in the first approach and one …

Reconstruction Of Finite Duration Signals, John A. Stuller

Electrical and Computer Engineering Faculty Research & Creative Works

The Problem of Reconstructing a Finite-Duration Finite- Energy Signal that Has Been Band Limited and Sampled is Considered. an Interpolation Formula is Derived that, in Principle, Permits Perfect Signal Reconstruction in the Noiseless Case Provided Only that the Sampling Frequency Exceeds the Cutoff Frequency of the Band-Limiting Filter. the Degradation Introduced by Measurement Noise on the Samples is Evaluated. © 1972, IEEE. All Rights Reserved.

Comments On “Accelerated Model-Reference Adaptation Via Lyapunov And Steepest Descent Design Techniques”, John S. Pazdera, Hugh F. Spewce

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

A State-Space Approach To Rlct Two-Port Transfer-Function Synthesis, Eddie R. Fowler, Rao Yarlagadda

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents an interesting procedure for the synthesis of an RLCT two-part transfer function. An RLC ladder, consisting of n reactive elements and two resistors, is derived by using a tridiagonal matrix developed by Navot. The entries in this matrix are expressed in terms of the element values of the ladder network. Two voltage drivers are introduced into the ladder network to obtain a desired short-circuit transfer-admittance function numerator degree, using the classical theorems on transmission zeros. If the numerator degree of the transfer function is i (i < n), then, in general, (i) ladder networks need to be derived. The final network, corresponding to this transfer function, is obtained by paralleling the ladder networks (with transformers if necessary). Extensions to general short-circuit transfer admittance, open-circuit transfer impedance, and voltage transfer functions are briefly discussed. © 1972, IEEE. All rights reserved.

An Experimental And Numerical Study Of Elastic Strain Waves On The Center Line Of A 6061-T6 Aluminum Bar, J. L. Habberstad, K. G. Hoge, J. Earl Foster

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The elastic strain waves resulting from the impact of two 3/4-in-dia 6061-T6 aluminum bars are studied experimentally and analytically. Experimental data are obtained from strain gages on the center line and outer surface of the bar, located at various distances from the impact end of the bar. Experimental data are compared to numerical results obtained from integrating the exact equations of two-dimensional motion. In general, agreement between the numerical and experimental results is very good. © 1972 by ASME.

Magnetohydrodynamic Stability Of The Developing Laminar Flow In A Parallel-Plate Channel, T. S. Chen, T. E. Eaton

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Linear stability of the developing laminar flow of an electrically conducting, incompressible fluid in a parallel-plate channel under a transverse magnetic field is investigated. The case of small magnetic Reynolds numbers is treated. The developing flows whose stability characteristics are studied correspond to those induced by a uniform and a parabolic velocity distribution at the channel inlet. The stability of the fully developed Hartmann flow is also reexamined. Neutral stability curves and axial variations of the critical Reynolds number are presented for a range of Hartmann numbers between 0 and 4. It is found that for Hartmann numbers larger than …

Forming Of 7075-T6 Aluminum In High Pressure Environments, Richard L. Pendleton, Robert L. Davis

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Plates of 7075-T6 Aluminum have been folded along a major axis in pressure environments of atmospheric, 20,000 psi, and 40,000 psi. A finite element computer program is used to determine the stress state in the plates at various loads. Tension and compression tests conducted in pressure environments up to 70,000 psi were used to construct models using effective stress, effective strain, and pressure as parameters to predict the behavior of the material under various stress conditions. A prediction of the occurrence of fracture in the folded plate was possible using the computer results and the pressure dependent model. As better …

Finite-Element Analysis Of Pressure Vessels, Robert L. Davis, H. Dean Keith

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The finite-element technique has been applied in the analysis of a variety of pressure vessel problems. The example problems described in this paper suggest that the finite element method is perhaps the most suitable means currently available for obtaining quick and accurate solutions for real-life pressure vessel problems. Finite-element programs can be used by the practicing engineer. Companion programs are available that can be used to check the input data and graphically display both the input and output data. © 1972 by ASME.

A Monte Carlo Calculation Of Neutron Reflection From Various Curved Surfaces, Charles Jack Kalter

Doctoral Dissertations

"Plane parallel neutron beams normally incident upon the curved surface of a solid reflector are studied with the Monte Carlo method. The geometries studied are cylindrical, parabolic, and hemispherical. It is shown that when the curved surface is cylindrical, a small "focusing effect" occurs in the reflected neutron beam. Parabolic and hemispherical surfaces do not show "focusing". A study of the factors which determine the spatial dependence of the reflected flux shows that the probability of emergence of a neutron, traveling a fixed distance from a point inside the reflector, depends upon the curvature of the surface. It is only …

Comprehensive Calculations Of The Parameters Describing Proton Energy Loss In Matter, Joseph F. Janni

Nuclear Engineering ETDs

Extensive calculations have been made of the mean energy loss, pathlength, range, multiple scattering, and pathlength straggling of protons in many materials. Emphasis has been placed on obtaining accurate results, especially for heavy materials and protons of very low energy. Values of the energy loss between .01 and 1.0 Mev were obtained by smoothing and interpolating experimental information. Above 1.0 Mev, the Bethe equation with all the necessary shell corrections has been used. Values of the adjusted ionization potential have been determined by least squares fitting the Bethe equation to all available energy loss data. The polarization effect has been …

Free Vibration Of Plates Stiffened By Parallel Ribs., Charles Edward Bacchus

Civil Engineering ETDs

A method is presented to obtain the natural frequencies and related mode shapes of certain types of stiffened plate systems. Dynamic stiffness matrices, based on ordinary assumptions in beam and plate theory, are derived to relate the displacements at the edges of a system element to the edge forces. Both in-plane and transverse forces and displacements are considered. Compatibility and equilibrium conditions at the intersections of plate panels and stiffening elements are employed to derive the governing equations of the system.

For general systems, the result is a set of linear homogeneous algebraic equations which must be solved by trial-and-error. …

Theoretical And Experimental Study Of Explosive Closures Of 6061-0 Aluminum Pipes, Lyle E. Edwards

Mechanical Engineering ETDs

This thesis examines the use of explosives to collapse metal pipes from an applications point-of-view. A particular system is studied, both theoretically and experimentally, in order to facilitate the future design of such closures with the least possible physical testing. The calculations are based on a rigid-perfectly plastic model of the observed deformations of the tubes, and on various assumed am derived properties of the metal and sheet explosives under the dynamic conditions of closure. A computer program has been devised which simulates the actual motion of a pipe during collapse. Experimental work involved actual test firing of aluminum cylinders …

Techniques For Active 3he Activation Analysis For Carbon And Oxygen, William Mort Sanders

Nuclear Engineering ETDs

The surface and body concentrations of carbon and oxygen have been measured in various materials using ³He activation. Channeling techniques have been used to differentiate between interstitial and substitutional location of these impurities.

Thin target excitation functions were determined for (³He,p) reactions with carbon and oxygen over a ³He energy range from 2.5 to 9.0 MeV. These data were used to calculate the activation curves for various combinations of incident particle energy, impurity distributions, and material.

Information on several computer codes used during this study is presented.

Computer Solution To Inverse Problems Of Elliptic Form: V²U(X,Y) = G(A,U,X,Y), Frederick Alvin Jeter

Dissertations and Theses

One important aspect of our present age of monolithic high speed computers is the computer's capability to solve complex problems hitherto impossible to tackle due to their complexity. This paper explains how to use a. digital computer to solve a specific type of problem; specifically, to find the inverse solution of a in the elliptical equation V²U(x,y) = g(a,U,x,y), with appropriate boundary conditions. This equation is very useful in the electronics field. The knowns are the complete set of boundary values of U(x,y) and a set of observations taken on internal points of U(x,y). Given this information, plus …

Thermal Expansion Of Tungsten At Low Temperatures, Jayant S. Shah, Martin E. Straumanis

Materials Science and Engineering Faculty Research & Creative Works

Lattice parameters, thermal expansion coefficients, and Grüneisen parameters of tungsten are determined by an x-ray method in the temperature range of 180-40 K without the use of liquid gases. Lattice parameters are expressed as a function of temperature. Thermal-expansion coefficients decrease with temperature and show no anomaly in contrast to a hypothesis proposed by Featherston and Neighbours. Grüneisen parameters γ are decreasing with temperature in accordance with the theoretical predictions. © 1971 The American Institute of Physics.

Current Mechanical Fastener Specifications And Test Procedure, John Fraczek

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

No abstract provided.

Front Matter, University Of Missouri--Rolla

Symposia on Turbulence in Liquids

No abstract provided.

Current Investigations Of Turbulent Shear, S. J. Kline, G. R. Offen, W. C. Reynolds

Symposia on Turbulence in Liquids

The paper covers first a short review of the history of research on turbulent shear and second a description of current experiments which may lead to further understanding.

The first portion categorizes the kinds of data which have been taken and discusses what can be learned from each. It then summarizes what is firmly established concerning the nature of turbulent shear, mostly from work of the past decade. A description of the several interpretations of these data under theoretic study by current leading researchers is then given.

The second portion of the paper discusses the extraordinarily difficult problem of identifying …

Interpretation Of Hot-Film Anemometer Response In A Non-Isothermal Field, W. E. Burchill, B. G. Jones

Symposia on Turbulence in Liquids

A new technique for interpretation of hot-film anemometer sensor response is described. This technique has been applied to simultaneous measurement of profiles of mean velocity, the three components of velocity vector fluctuation, and temperature fluctuation in non-isothermal pipe flow of water using multiple sensors. Sensors operated in the constant temperature mode (CTA) respond to both mean and fluctuating velocity and temperature. The influence of mean temperature gradient on CTA sensor response was eliminated by appropriate adjustment of the sensors' operating resistances as the temperature gradient was traversed. The adjustments were derived from analysis of linearized CTA sensor response. A sensor …