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The Lifetime And Effective Quenching Cross Section Of The 6²P₃/₂ State Of Thallium, Robert Charles Pickett Jan 1968

The Lifetime And Effective Quenching Cross Section Of The 6²P₃/₂ State Of Thallium, Robert Charles Pickett

Doctoral Dissertations

"The measurement of the lifetime of the metastable 6²P₃/₂ state of thallium is discussed. Measurement of time varying optical absorption by time sampling techniques is explained for the study of the decay of the metastable atom concentration following a pulsed radio frequency discharge. The decay of the thallium radiation from optically allowed states terminating on the metastable state is measured at nine different thallium densities in the afterglow of the discharge. This radiation repopulates the metastable state and is displayed on an oscilloscope. The metastable lifetime is measured as a function of the thallium density at three different r-f power …

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Inferences On The Parameters Of The Weibull Distribution, Darrel Ray Thoman Jan 1968

Inferences On The Parameters Of The Weibull Distribution, Darrel Ray Thoman

Doctoral Dissertations

"For the most part, solutions to the problems of making inferences about the parameters in the Weibull distribution have been limited to providing simple estimators of the parameters. Little has been known about the properties of the estimators. In this paper the small and moderate sample size properties of the maximum likelihood estimators are studied and their superiority is established. The problem of making further inferences which are based on the maximum likelihood estimates of the parameters is then considered. The inferences that are presented can be divided into those based on a single sample and those based on two …

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Investigation By Neutron Diffraction Utilizing White Neutron Radiation, Arlen Ray Schade Jan 1968

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 …

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Recombination Statistics For The Neutron-Induced Base Current Component, Ming-Chwan Chow Jan 1968

Recombination Statistics For The Neutron-Induced Base Current Component, Ming-Chwan Chow

Doctoral Dissertations

"This paper presents a derivation of the recombination statistical model for the neutron-induced base current component. The derivation was based on the assumptions: 1) the current equation for the induced current component developed by Goben is valid; 2) the Shockley-Read-Hall statistics for holes and electrons are applicable; and 3) the recombination statistics derived by Sah, Noyce and Shockley, for sites in the bulk space-charge region are valid. Several examples were presented to emphasize accuracy of this derived model for predictions. This paper shows that the recombination process may be described by a mathematical model, recombination statistics which depend on the …

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Surface Self-Diffusion On Nickel (111) By Radioactive Tracers, James Ronald Wolfe Jan 1968

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 (Ds) 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 …

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A Comparison Of Three Numerical Techniques Used For The Solution Of The Two-Point Boundary Value Problem, William Richard Krall Jan 1968

A Comparison Of Three Numerical Techniques Used For The Solution Of The Two-Point Boundary Value Problem, William Richard Krall

Masters Theses

"Three numerical approximation techniques, called the Initial step, Shooting, and Direct Finite Difference Techniques, respectively, are compared and discussed as they apply to the solution of both linear and non-linear boundary-value problems of the form y"=f(x,y,y') with endpoint conditions y(xo)=yo and y(xn)=yn. The techniques are compared with respect to speed and accuracy by comparing the solution of each problem considered four times, each time for a different increment value, and comparing the errors at four pivotal points chosen at equally spaced distances over the domain of the function, to give an indication of …

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Surface Interactions Between Nickel Ions And Sodium Dodecyl Sulfate, Ralph Edward Coleman Jan 1968

Surface Interactions Between Nickel Ions And Sodium Dodecyl Sulfate, Ralph Edward Coleman

Masters Theses

"In this research the interaction of nickel ions with the surfactant sodium dodecyl sulfate at the liquid-air interface was studied. Surface tension measurements were performed on pure sodium dodecyl sulfate solutions, with and without the addition of nickel ions. Results of these measurements showed that the addition of nickel ions lowered the equilibrium surface tension values of pure sodium dodecyl sulfate solutions and shifted the critical micelle concentration to lower concentrations. The foam fractionation technique was used to determine if the nickel ions could be removed from surfactant solutions. It was found that the removal of nickel ions was influenced …

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Determination Of Molecular Diffusivities In Liquids, Pai-Chuan Wu Jan 1968

Determination Of Molecular Diffusivities In Liquids, Pai-Chuan Wu

Masters Theses

"A porous plate, initially at a uniform solute concentration is immersed in a well-stirred pure solvent bath of known volume. It is desired to find the molecular diffusivity of the solute-solvent system by observing the change of the solute concentration in the solvent bath with time. In this study, concentration-time data were curve-fitted by non-linear, least squares techniques to the various mathematical solutions describing molecular diffusion in the porous frit. This technique is used to determine the diffusion coefficient and predict the value of other parameters existing in the different mathematical diffusion models. The results from the different models are …

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Lattice Parameters, Coefficients Of Thermal Expansion, Densities, And Lattice Perfection Of The Copper-Indium Primary Solid Solutions, Lin Sheng Yu Jan 1968

Lattice Parameters, Coefficients Of Thermal Expansion, Densities, And Lattice Perfection Of The Copper-Indium Primary Solid Solutions, Lin Sheng Yu

Masters Theses

"Precise measurements of lattice parameters and densities of the alpha-phase Cu-In solid solutions were made at temperatures of 25°C. The thermal expansion coefficients between 15 and 65°C, the solid solubility of In in Cu at 650°C, and the soundness of crystal structure resulting from alloying were determined. The Cu-In alloys were prepared from high purity (99.999%) Cu and In by melting both metals inside evacuated quartz tubes. The solidified alloys were annealed and then examined by X-ray for homogeneity...The slowly solidified alpha-phase alloys gave densities lower than the theoretical (X-ray) values due to the presence of shrinkage microporosity. This density …

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Drag Reduction In Hydrocarbon Soap Solutions, Ian Radin Jan 1968

Drag Reduction In Hydrocarbon Soap Solutions, Ian Radin

Masters Theses

"Turbulent flow pressure drop measurements were made for solutions of aluminum dioleate (soap) in toluene at concentrations of 0.2, 0.5, 0.75 and 1.0 per cent. Tube diameters ranged in size from 0.01 to 2.0 inches. The results of these measurements differed from those observed in aqueous systems. Higher concentrations (at least 0.75 per cent) were required before drag reduction was observed. Although fresh solutions were somewhat sensitive to shearing, once a solution was over about two weeks old it showed little further mechanical degradation. Although in the toluene solutions, wall shear stresses were reached which were over an order of …

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The Numerical Solution Of Two-Dimensional Fluid Flow Problems, E. David Spong Jan 1968

The Numerical Solution Of Two-Dimensional Fluid Flow Problems, E. David Spong

Masters Theses

"A numerical solution method is developed for the solution of two-dimensional, irrotational and compressible fluid flow problems. The partial differential equation, in terms of the velocity potential, describing the flow is replaced by finite difference equations and the resulting matrix is solved by Gaussian elimination. The method is successfully applied to two subsonic flow problems: a 7.5⁰ wedge and a 6⁰ wedge inlet. The method becomes invalid, as expected, with the appearance of sonic velocity in the flow field. An investigation of the definition of the singularities is made. This indicates that the best agreement with the experimental results for …

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Sufficiency Conditions For Constrained Optima, Cheng-Chun Huang Jan 1968

Sufficiency Conditions For Constrained Optima, Cheng-Chun Huang

Masters Theses

"The sufficiency conditions for constrained optimization problems are derived through the use of Lagrangian functions and through the introduction of the new concept of "constrained total derivatives." The relations can be used with equality and/or inequality constraints. The sufficiency conditions derived earlier by Phipps were corrected in this work--Abstract, page ii.

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Endogenous Metabolism Of Polyporus Sulfureus. : Utilization Of Exogenous Carbohydrates And Fatty Acids, Shu-Mei Wang Jan 1968

Endogenous Metabolism Of Polyporus Sulfureus. : Utilization Of Exogenous Carbohydrates And Fatty Acids, Shu-Mei Wang

Masters Theses

"A strain of Polyporus sulfureus from the collection at the University of Missouri at Rolla was used in this investigation. Organisms of this genus have been reported to produce eburicoic acid in good yield and this was confirmed for the organism used in this study by the isolation and identification of eburicoic acid from the mycelium. Growth studies of this organism showed that 4% malt extract is a better medium than synthetic media containing asparagine, nitrate or nitrate plus 0.5% yeast extract as nitrogen sources. An examination of the pH of the culture medium led to the conclusion that regardless …

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A Study Of Swirling Air Flow In A Converging Nozzle, Charles William Lineberry Jan 1968

A Study Of Swirling Air Flow In A Converging Nozzle, Charles William Lineberry

Masters Theses

"A study was conducted to determine the behavior of swirling air flow in a converging nozzle. Special instrumentation was constructed to obtain radial traverses of the flow at four axial positions. the data collected consisted of velocity, static pressure, and stagnation temperature. The flow pattern demonstrated the Ranque-Hilsh effect and reversed axial flow in the core region. As the flow entered the nozzle, it had the characteristics of a free vortex. At the exit plane the characteristics were those of a forced vortex. The converging nozzle caused an increase in the magnitude of the axial velocity component"--Abstract, page ii.

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Spacing Of Explosive Charges, Calvin J. Konya Jan 1968

Spacing Of Explosive Charges, Calvin J. Konya

Masters Theses

"It is generally believed that the spacing of simultaneously initiated collar primed multiple charges is not dependent on the charge length. The stresses generated by explosive charges have been assumed to propagate through a material in a cylindrical manner. this assumption implied that the stress generated in any plane along the charge diameter would have been uniform in magnitude and direction. A finite explosive velocity along with a conical stress wave causes the stresses near the collar to differ from those farther down the column. for this reason, the spacing of charges would be dependent on charge length. An experimental …

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Radiation And Annealing Characteristics In Neutron Bombarded Transistors Operated In The Inverse Configuration, Lo-Soun Su Jan 1968

Radiation And Annealing Characteristics In Neutron Bombarded Transistors Operated In The Inverse Configuration, Lo-Soun Su

Masters Theses

"When operating a silicon planar epitaxial transistor in the inverse configuration (i.e., with the emitter functioning as a collector and the collector functioning an emitter) the bulk space-charge volume of the new "emitter-base" junction is increased by a factor of 26.5 times that of the normal emitter-base junction. The carrier concentration in the new "emitter" is decreased by five orders of magnitude from that of the normal emitter, thus making it easier to investigate the effects of neutron radiation on the space-charge region and at the surface. Experiments using biasing of the new "emitter-base" junction during neutron radiation to change …

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A Study Of Porous Membrane Evaporation For Desalination In A Flow System, Jing Ming Lee Jan 1968

A Study Of Porous Membrane Evaporation For Desalination In A Flow System, Jing Ming Lee

Masters Theses

"The purpose of this investigation was to study the simultaneous mass and heat transfer mechanism in evaporation through a porous membrane with a non-wettable surface. Such water repellent membranes permit the passage of water vapor, but not liquid water. The investigation concerned the mass transfer rate through the membrane pores with flow on one or both sides of the membrane. The water-repellent membrane separated a hot salt solution from the fresh water, and a copper sheet separated the fresh water from a cold salt solution. A three-channel evaporator-condenser was used, and the membrane consisted of glass fiber paper treated with …

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A Study Of Bismuth Ferrate And Bismuth Manganate In Solid Solution With Lead Titanate, Harris C. Jones Jan 1968

A Study Of Bismuth Ferrate And Bismuth Manganate In Solid Solution With Lead Titanate, Harris C. Jones

Masters Theses

"A new sample holder for measuring the high frequency dielectric constant of ferroelectrics at high temperature was constructed. The new sample holder eliminated discontinuities in the slotted line and improved the electrical contact between the ceramic and brass components. Measurements of the high frequency dielectric constant of an aged sample of 90% BiFeO₃ - 10% PbTiO₃ were made as a function of temperature using the slotted line technique. The dissipation function for the aged sample was found to have a more normal behavior near the Curie point than the virgin samples previously measured. Resistivity measurements were made as a function …

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Instrumentation Of A Shock Tube Facility, James Everett West Jan 1968

Instrumentation Of A Shock Tube Facility, James Everett West

Masters Theses

"The theory of schlieren and interferometer systems was described and related to studies of shock waves in a shock tube. An interferometer was procured and a schlieren system was modified for use with the UMR shock tube facility. The design and construction of a base for the systems and window assemblies for the shock tube comprised the major portion of the work on this project. A short series of tests were run to ascertain the compatibility of the instrumentation to the UMR shock tube facility. While no schlieren photograph of the shock wave was obtained, the system was shown to …

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An Intensity Regulation System For A Monochromator, David A. Wayne Jan 1968

An Intensity Regulation System For A Monochromator, David A. Wayne

Masters Theses

"In the investigation of phenomena involving both optical intensity and wavelength, an instrument is often desired which allows one of the quantities to be held constant while the other is varied. A relatively inexpensive system is described which utilizes a commercial grating monochromator and external feedback electronics to regulate the output intensity as the wavelength is varied. In this system, a sample of the output intensity is taken by a photosensor with known spectral response. The output of the photosensor is then compared electronically with that of a pre-programmed function generator which cancels nonlinearities in the photo-sensor. The resulting signal …

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Absolute Specification Of X-Ray Spectra By Laplace Transform Analysis Of Attenuation Data, Gerald Robert Lusk Jan 1968

Absolute Specification Of X-Ray Spectra By Laplace Transform Analysis Of Attenuation Data, Gerald Robert Lusk

Masters Theses

"A well characterized, variable plate separation ion chamber was utilized as a detector to collect x-ray attenuation data for generating information on the Laplace transform predicted spectrum of a 50 KvCP conventional x-ray tube. The variable plate separation feature allows one to include a wavelength dependent correction to the detector response which is associated with the hardening of the x-ray spectrum as it traverses the attenuating material. With this correction, the conventional two-term Laplace transform was shown to approximate independently the bremsstrahlung and characteristic L radiation from the tungsten target. The detector provides an absolute statement of the target-referenced x-ray …

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Design And Construction Of A Liquid Nitrogen Cryostat For Use In A Swimming Pool Type Reactor, Bruce B. Joiner Jan 1968

Design And Construction Of A Liquid Nitrogen Cryostat For Use In A Swimming Pool Type Reactor, Bruce B. Joiner

Masters Theses

"The continued expansion of the nuclear reactor facility and the nuclear engineering program dictates the need that a liquid nitrogen cooled cryostat be available at the reactor. This unit would be available for use in graduate and undergraduate laboratories and for graduate research. A liquid nitrogen cooled cryostat capable of maintaining a sample between 77°K to 80°K for an extended period of time in or adjacent to the core of the reactor was designed, constructed, and successfully operated. Recommendations were made for possible modifications to expand the versatility of the system"--Abstract, page ii.

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The Modeling, Fabrication, And Testing Of An Instantaneous Torque Measuring System, Thomas Phillip Hertel Jan 1968

The Modeling, Fabrication, And Testing Of An Instantaneous Torque Measuring System, Thomas Phillip Hertel

Masters Theses

"The purpose of this work was to obtain a measuring system to experimentally determine the instantaneous magnitude and frequency of the torques from zero to 2400 Hertz produced by a single phase motor. This paper explains the methods employed in designing and fabricating a measuring system and shows the results from tests using this equipment. It was found that a measuring system based on the determination of the instantaneous value of the stator's reaction torques could be realized. Also, it was found that some simple methods of computation could be used to find the magnitudes of the frequency components comprising …

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Cell Model Of A Fluid. I. Evaluation Of The Partition Function And Series Expansions, Ralph G. Tross, Louis H. Lund Jan 1968

Cell Model Of A Fluid. I. Evaluation Of The Partition Function And Series Expansions, Ralph G. Tross, Louis H. Lund

Physics Faculty Research & Creative Works

The partition function of a one-dimensional system of particles with all interactions active is formulated in terms of Ising ferromagnetic spin states. It is shown how the partition function for two- and three-dimensional systems can be obtained from the one-dimensional one by restricting the number of bonds per particle. After writing the partition function in matrix form, the operator of interest is diagonalized and its trace expressed in the form of a convenient infinite series. The series is shown to be absolutely convergent and its analytic properties are briefly investigated. It is then applied to one-, two-, and three-dimensional systems …

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Cell Model Of A Fluid. Ii. Thermodynamic Properties Of The System, Ralph G. Tross, Louis H. Lund Jan 1968

Cell Model Of A Fluid. Ii. Thermodynamic Properties Of The System, Ralph G. Tross, Louis H. Lund

Physics Faculty Research & Creative Works

In Paper I of this series (preceding paper) the model was formulated mathematically, and the solution derived in the form of an infinite series. The convergence and analyticity of the solution were investigated. It was then applied to one-, two-, and three-dimensional systems with nearest-neighbor interactions, and low-temperature series for these systems were obtained. In the present article the thermodynamics of the model are investigated. The series solution of the partition function derived in Paper I is applied to systems with interaction potentials of increasing complexity. The validity of the model is established by showing that in the appropriate limits …

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Neutron Radiation Damage In Silicon Transistors, C. A. Goben, F. M. Smits, J. L. Wirth Jan 1968

Neutron Radiation Damage In Silicon Transistors, C. A. Goben, F. M. Smits, J. L. Wirth

Electrical and Computer Engineering Faculty Research & Creative Works

In the investigation of base and collector current as a function of the emitter-to-base voltage, previous studies have shown that neutron-induced base current has components originating in the emitter space charge region as well as the neutral base region. This study shows that while the low injection level neutron-induced base current is dominated by the space charge component, the high injection behavior appears to be controlled by recombination in the neutral base region. Additional experiments performed in special tetrode transistors and van der Pauw-type samples indicate that changes in collector current are dominated by recombination in the neutral base, while …

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Numerical Differentiation Of Equally Spaced And Not Equally Spaced Experimental Data [3], Harry C. Hershey, Jacques L. Zakin Jan 1968

Numerical Differentiation Of Equally Spaced And Not Equally Spaced Experimental Data [3], Harry C. Hershey, Jacques L. Zakin

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

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Corrosion Rates And Electrokinetics Of Cobalt And Cobalt-Rich Cobalt-Iron Alloys In Sulfuric And Hydrochloric Acids, Cheng Tzong Horng Jan 1968

Corrosion Rates And Electrokinetics Of Cobalt And Cobalt-Rich Cobalt-Iron Alloys In Sulfuric And Hydrochloric Acids, Cheng Tzong Horng

Masters Theses

"Corrosion rates for Co and Co-rich Co-Fe alloys were determined in sulfuric and hydrochloric acids under both deaerated and oxygenated conditions. For the purpose of comparison, corrosion rates of Co cut from metal sheet were also determined in the same environments as those of sintered alloys. Sintered alloys were inferior to solid Co as corrosion resistant materials. It was found that the surface was more corrosion resistant than the interior. Thus after long exposure to the corrosive acid, the samples became porous inside while the surfaces remained substantially intact. Oxygen had a pronounced effect in accelerating the corrosion of Co …

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Thixotropic Effects In A Clay-Water System, John Arthur Mathes Jan 1968

Thixotropic Effects In A Clay-Water System, John Arthur Mathes

Masters Theses

"Fundamental aspects of thixotropic phenomena are described, and previous investigations of thixotropic behavior in soil systems are summarized. The complex nature of the thixotropic phenomena as well as its general occurrence in fine grained soils is described. As existing hypothesis for thixotropic behavior based on initial non-equilibrium conditions is examined. Experimental results, as determined from a testing program on the Putnam clay, verify this hypothesis. The rate and magnitude of thixotropic strength increases of the Putnam clay were determined. Shear strength determinations were made by the unconfined compression and laboratory vane shear tests. The results of the tests were compared …

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The Analysis Of A Phase-Locked Loop By The Functional Expansion Method, Hugh Francis Spence Jan 1968

The Analysis Of A Phase-Locked Loop By The Functional Expansion Method, Hugh Francis Spence

Masters Theses

"The time response of a generalized second order Phase-Locked Loop to step and ramp inputs is described by a functional power, truncated at the third order term. The responses given by the functional power series differs from the analog simulation by less than 6% when the inputs are below 2.0 rad (rad/sec)"--Abstract, page ii.

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