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Optical Reflectance Spectra Of Chromium (Iii) In Mgo-Ss, Thomas Spencer Montgomery Jan 1968

Optical Reflectance Spectra Of Chromium (Iii) In Mgo-Ss, Thomas Spencer Montgomery

Doctoral Dissertations

"The valence state and coordination site of the transition-metal ion, chromium, was investigated in a MgO host lattice. The chromium ion incorporated into poly-crystalline MgO by quenching from elevated temperatures allowed investigation of a single crystalline phase, MgO-solid solution (ss). The chromium ion was confirmed to occur in the trivalent state and to occupy octahedral cation sites in the MgO lattice by the use of optical reflectance spectroscopy. The effect of the concentration of the chromium ion on the crystal field splitting energy, 10 Dq, permitted analysis over a range of Dq/B values. In conjunction, MgO-ss lattice parameters examined as …


Analytical And Experimental Methods For Determining The Properties Of Materials At Very High Rates Of Loading, A. G. Behring Jan 1968

Analytical And Experimental Methods For Determining The Properties Of Materials At Very High Rates Of Loading, A. G. Behring

Masters Theses

"In the following report, some of the properties of ALCOA 7075 T651 aluminum, when subjected to high rates of loading, are experimentally investigated by impacting two rods of the material longitudinally. One rod is accelerated to a uniform velocity with an air gun launcher. The stationary second rod is instrumented with strain gages on its lateral surface in order to determine the strain-time history following impact. A detailed description of the experimental equipment is included. Simple, one-dimensional theory is used to determine the dynamic, elastic modulus of the test material under the impact condition. Several observations regarding the behavior of …


The Design Of A Hybrid Computer System, James Joseph Becker Jan 1968

The Design Of A Hybrid Computer System, James Joseph Becker

Masters Theses

"Three typical hybrid computers in industry and educational institutions are presented. The hybrid computer designed and built at the University of Missouri at Rolla consists of an SCC-650 digital computer, a TR-48 analog computer, and a hybrid interface. The interface permits the digital computer to control the modes of operation on the analog computer. There are also 9 multiple-pole relays on the interface that can be controlled by the digital computer. A 320 hold removable patchboard is included in the interface. There are 40 trunks lines from the analog computer that are present on the patchboard. The 4 digital-to-analog channels …


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 …


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 …


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 …


The Design Of A Tape Deck Controller, Frederick Harold Keeve Jan 1968

The Design Of A Tape Deck Controller, Frederick Harold Keeve

Masters Theses

"A controller was built to interface the SCC-650 general purpose digital computer and the Kennedy Model 1400R incremental write/continuous read tape unit. All logic design information, signal lists, and tape deck instructions are included"--Abstract, page ii.


Construction Time And Cost Control Using The Ibm Project Management System/360, James Donald Bailey Jan 1968

Construction Time And Cost Control Using The Ibm Project Management System/360, James Donald Bailey

Masters Theses

"The object of this investigation was to determine the advantages or disadvantages involved in the use of the IBM Project Management system/360 as a time and cost control tool as compared to the methods presently used by construction contractors in the small to medium size range.

The methods used by three construction contractors were investigated in order to acquire a sample of methods presently used.

It was determined from the investigation that a number of advantages could be obtained which would provide better control of a construction project.

It was also decided that a detailed investigation concerning the cost of …


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 …


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.


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.


Compressive Creep Of Basic Refractories, Maurice E. Green Jan 1968

Compressive Creep Of Basic Refractories, Maurice E. Green

Masters Theses

"The microstructure and mineralogical composition of direct bonded, 50 wt.% magnesia - 50 wt.% chrome ore refractory compositions containing controlled additions of silica were correlated with their compressive creep behavior in the temperature range 1450⁰ to 1550⁰C under stresses of 100 to 175 psi. Steady state creep rates were determined from the linear regression of the steady state regions of deformation on time. Apparent activation energies and deformation flow characteristics were determined from the temperature and stress dependence of the steady state creep rates. Silica contents up to 3.5 wt.% increased the amount of direct intergranular bonding which decreased the …


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 …


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 …


An Intragastric Ph And Motility Monitoring And Automatic Titration System, Barry Foster Maycock Jan 1968

An Intragastric Ph And Motility Monitoring And Automatic Titration System, Barry Foster Maycock

Masters Theses

"Knowledge of the effects of prolonged states of weightlessness on the physiological activities of gastric motility and acid secretion will aid in the planning of future space flights, since aberrations in these activities could affect the performance of astronauts. Investigation of these activities requires monitoring of the pressure and pH in the stomach and titration of the gastric contents. Since previous methods and equipment used for performing these functions are inadequate for this investigation, the equipment whose design and operation are discussed in this thesis was developed. This equipment includes an ingestible sensor capsule which is tethered in the stomach, …


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 …


The Decomposition Of 5-Hydroxymethyl-2-Furaldehyde Under Gamma Irradiation, William George Bowles Jan 1968

The Decomposition Of 5-Hydroxymethyl-2-Furaldehyde Under Gamma Irradiation, William George Bowles

Masters Theses

"An investigation into the effects of gamma irradiation decomposition of 5-hydroxymethyl-2-furaldehyde (HMF) revealed HMF to be resistant to radiation catalyzed decomposition. A 1.0 normal solution of HMF was irradiated at a dose rate of 4.1 x 10⁵ Rads/hr to a total dose of 8.2 x 10⁶ Rads from a 5000 Curie ⁶⁰Co source. a total of 31 per cent of the HMF decomposed in a zero order reaction, although it was found the HMF decomposed completely under cadmium shielded irradiation in a nuclear reactor with some neutrons present. The reaction rate constant was found to be 4.8 x 10⁻³ moles …


Investigation Of Thermal Resistance At The Interface Of Dissimilar And Similar Metals, Ching-Liang Lin Jan 1968

Investigation Of Thermal Resistance At The Interface Of Dissimilar And Similar Metals, Ching-Liang Lin

Masters Theses

"Experiments have been conducted to investigate the resistance and the effect of the directional heat flow at the interface of metals in contact. The test specimens were cylinders, axially aligned and dead weight loaded. Specimen materials were aluminum, bronze, and steel. The tests were conducted at environment pressures of 5x10⁻⁵ Torr. or less. The dead weight load was kept at 10 lbs. for all tests and the surface roughness for all specimens was from 6 to 8x10⁻⁶ inch. The results of the investigation reveal that the resistance to heat flow at the interface of metals decreases as the interface temperature …


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 …


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 …


The Effect Of Prior Cold Work On The Pressure Welding Of Ferritic Nodular Iron, Ronald Morris Ledbetter Jan 1968

The Effect Of Prior Cold Work On The Pressure Welding Of Ferritic Nodular Iron, Ronald Morris Ledbetter

Masters Theses

"The purpose of this investigation was to determine the effect of prior cold work by swaging on the pressure welding of ferritic nodular iron. Test pressure welds were produced from continuously cast ferritic nodular iron in the as cast condition and with prior cold work of 20, 30, 40, and 50 per cent reductions in area. Welding pressures of 23,500 psi, 35,300 psi, and 47,100 psi were employed. All welds were made at interface temperatures of 2000°F. Welds made with the as cast material at high welding pressures possessed relatively low tensile strengths due to the creation of planes of …


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.


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 …


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 …


The Effects Of Grinding On The Physical Properties Of Clay Soils, Thomas Michael Mcmillen Jan 1968

The Effects Of Grinding On The Physical Properties Of Clay Soils, Thomas Michael Mcmillen

Masters Theses

"Studies of the effect of grinding on clay soils are summarized. Fundamental aspects of thixotropic phenomena are also explored. Vetters clay and Lebanon silt loam are used as test soils. these soils are ground to varying degrees and the deviations in physical properties are determined. Atterberg Limits, specific gravity, grain size, X-ray diffraction, and D.T.A. tests are run on each soil batch (ground for 0 minutes, 30 minutes, 60 minutes, and 120 minutes). A thixotropic study, consisting of unconfined compression and laboratory vane shear tests, of each soil batch is made. The results of the tests are analyzed, compared, and …


Dynamic Capacitance Of Metal-Oxide-Semiconductor Field-Effect Transistors, Marion Wendell Tucker Jan 1968

Dynamic Capacitance Of Metal-Oxide-Semiconductor Field-Effect Transistors, Marion Wendell Tucker

Masters Theses

"A transient peak was observed for MOSFET devices when measuring the dynamic capacitance versus applied gate voltage for various configurations at low frequencies. This peak is absent in conventional steady-state ac measurements. Since the peak is also absent in high grade devices and at high frequencies a possible explanation in terms of surface state traps is discussed for the observed phenomena"--Abstract, page ii.


The N-Wire Exponential Transmission Line, Vernon Ray Stanley Jan 1968

The N-Wire Exponential Transmission Line, Vernon Ray Stanley

Masters Theses

"This paper deals with the n-wire exponentially tapered transmission line. A characteristic impedance is defined, and the results of terminating in this impedance are investigated. A very long line and the condition of no reflections are considered, and the conclusions are compared. Finally, three specific 3-wire line problems are worked with a characteristic impedance termination and a unit step input"--Abstract, page ii.


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 …


A Comparison Of Proportional And Nonproportional Damping In Multistory Shear Buildings, Edwin C. Bailey Jan 1968

A Comparison Of Proportional And Nonproportional Damping In Multistory Shear Buildings, Edwin C. Bailey

Masters Theses

"The purpose of this study was to determine whether proportional damping could be used to satisfactorily simulate the more practical nonproportional damping condition in multistory shear buildings. To accomplish this one computer program was written to analyze proportionally damped systems and another to analyze nonproportionally damped systems, each giving as output the frequencies, mode shapes, displacements, shears and moments and the maximum shears and moments. Shear buildings of two, three and four stories were studied in which the damping coefficients were varied from one to ten percent of critical damping. Although the programs could handle various other types, only linearly …


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 …