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A Study Of A New Hydrometallurgical Treatment For New Lead Belt Chalcopyrite Concentrates, Larry Steven Livingston Jan 1973

A Study Of A New Hydrometallurgical Treatment For New Lead Belt Chalcopyrite Concentrates, Larry Steven Livingston

Masters Theses

"A two-phase research project was conducted on chalcopyrite concentrates from the New Lead Belt of Missouri. Phase one includes an ore microscopy study of the Magmont and Viburnum chalcopyrite concentrates in respect to mineralogy, particle size and interlocking characteristics of ore minerals and their possible relationships to poor chalcopyrite-galena separation in the copper flotation circuits.

Results of the ore microscopy study of the Magmont and Viburnum mines chalcopyrite concentrates suggest that interlocking of chalcopyrite and galena are not the cause of poor chalcopyrite-galena separation in the copper flotation circuits.

The most common sulfides found in the Magmont and Viburnum chalcopyrite …


Ideal Filter Approximation And Synthesis, Patrick Shu Yau Ho Jan 1973

Ideal Filter Approximation And Synthesis, Patrick Shu Yau Ho

Masters Theses

"Several methods are currently used for approximating the ideal low pass filter. Generally, those approximations relate only to the amplitude or phase characteristic of the ideal filter. A class of filters has been proposed as approximating both the amplitude and phase characteristics of the ideal filter. The characteristics of the first ten members of the proposed class are considered in this paper. The results indicate a much improved approximation to the ideal filter has been achieved"--Abstract, page ii.


Driver-Vehicle-Roadway Interaction Model, Mark E. Jaeger Jan 1973

Driver-Vehicle-Roadway Interaction Model, Mark E. Jaeger

Masters Theses

"A non-trivial simulation model has been developed which combines driver and vehicle dynamics with the roadway into one system. The model was successfully simulated on a portion of an existing roadway with the dynamic response and performance of the simulator being subjectively realistic. By implementing the idea of the interaction of variables, a much more detailed and representative response is obtained as compared to previous models based solely upon a single-factor-effect approach. By analyzing a simulated vehicle's velocity and trajectory, it is felt that an increase in driver "look ahead" distance or a decrease in vehicle velocity tends to improve …


Statistical Analysis Of Critical Flashover Voltage And Standard Deviation Of Switching Surges And Lightning Impulses, Gurdip Singh Jan 1973

Statistical Analysis Of Critical Flashover Voltage And Standard Deviation Of Switching Surges And Lightning Impulses, Gurdip Singh

Masters Theses

"In order to analyze critical flashover voltage methods a set of experimentally determined data has been used. This data was supplied by the A. B. Chance Company. The data presents the flashover probability as regards to impulse voltage. The various correction factors have been applied to get the corrected impulse voltage, thus eliminating the effect of atmospheric conditions such as temperature, pressure, and humidity. The experimental observations have been analyzed by the application and use of the method of moments, regression analysis, graphical analysis with iterative techniques and maximum likelihood method. From the results, it was found that the maximum …


Distribution Of Trace Elements In Host Rock Limestone In The Tri-State Zinc-Lead District, Dinesh Jashbhai Patel Jan 1973

Distribution Of Trace Elements In Host Rock Limestone In The Tri-State Zinc-Lead District, Dinesh Jashbhai Patel

Masters Theses

"The trace metal contents of limestone in the Tri-State zinc-lead district were determined within a single horizon, the M bed. Ninety-six specimens, collected for a previous study of their petrographic character, were analyzed for zinc, lead, and copper using atomic absorption spectrophotometric techniques.

The unaltered M bed limestone at a distance from ore bodies was found to contain only 12-28 ppm zinc, 40-SO ppm lead and 12 ppm or less copper. Those limestone specimens which were found b earlier petrographic study to be altered principally to sparry calcite commonly contain anomalous amounts of zinc and lead. Some also have slightly …


Design And Construction Of An Electronic Pressure Altimeter For An Atmospheric Data Acquisition System, Larry Wayne Berkbigler Jan 1973

Design And Construction Of An Electronic Pressure Altimeter For An Atmospheric Data Acquisition System, Larry Wayne Berkbigler

Masters Theses

"This thesis describes the design, construction, and application of an altimeter which was developed as part of the data acquisition system of a small aircraft used to study atmospheric conditions. The altimeter provides a digital readout and interfaces with analog and digital recorders. It can also provide an audio indication when a predetermined altitude is reached. The altimeter is powered by 12 volts dc, has resolution to 10 feet, and a maximum altitude of 15,000 feet. Its maximum theoretical error is ±78 feet ±0.77% of true altitude, which is an error of ±194 feet at 15,000 feet.

Since the unit …


Management Of Passive Countersurveillance In The R & D Environment, James Ronald Carney Jan 1973

Management Of Passive Countersurveillance In The R & D Environment, James Ronald Carney

Masters Theses

"Existing management procedures that are pertinent to research and development activities within the Government are presented. The main focus of this effort is on the Mobility Equipment Research and Development Center’s Countersurveillance and Topographic Division, and highlights the relevant plans, documents, programs, and reporting systems utilized by the Army and the Department of Defense. An in-depth examination is made on the need for Countersurveillance in the Army. The Army’s existing Countersurveillance research and development missions and programs are reviewed.

A detailed investigation and analysis is performed on current management concepts and techniques that are utilized in research and development endeavors. …


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

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

Masters Theses

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

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


An Experimental Analysis Of Oil Spill Drift Caused By Water Waves, Jan Michael Pottinger Jan 1973

An Experimental Analysis Of Oil Spill Drift Caused By Water Waves, Jan Michael Pottinger

Masters Theses

"A study was conducted to determine the effect of waves on oil spill drift. The investigation was performed in a long narrow tank equipped with a mechanical wave generator at one end and a beach to suppress wave reflection at the other end. It was found that a special procedure for taking data was necessary in order to assure that the data was consistent and that the waves were indeed deep water waves, and therefore similar to open ocean conditions.

The data indicated that waves do influence oil spill movement, and the velocity of the oil was found to be …


The Contribution Of Phonon-Induced Tunneling To Donor Esr Spectral Narrowing In Semiconductors, David Lawrence Meier Jan 1973

The Contribution Of Phonon-Induced Tunneling To Donor Esr Spectral Narrowing In Semiconductors, David Lawrence Meier

Masters Theses

"The narrowing of donor electron spin resonance spectra with increasing donor concentration ND and increasing temperature T has been observed in semiconductors in the past. One proposed explanation for this phenomenon has been narrowing due to electron motion caused by phonon-induced tunneling (hopping) between donor sites. According to the Anderson narrowing theory, the line width of the narrowed line can be expressed in terms of the average square spread of the non-narrowed spectrum, < H²>ave, and the average frequency of electron motion, ωn. Previous work has been done on narrowing by hopping, but rigorous expressions for ω …


Monte Carlo Simulation Of Confidence Intervals For Reliability, Kathryn Palisch Berkbigler Jan 1973

Monte Carlo Simulation Of Confidence Intervals For Reliability, Kathryn Palisch Berkbigler

Masters Theses

"A computer program which computes fiducial confidence intervals for reliability by Monte Carlo simulation has been written. The program has the capability of computing these intervals for general systems of series, parallel, and mixed series and parallel subsystems which have failure time distributions which are either exponential, Weibull, gamma, normal, or lognormal.

Comparison of the simulation technique with a Bayesian technique for computing confidence intervals in the case of a series of exponentially distributed components shows that the two methods agree quite well when a fiducial prior distribution for reliability is used in the Bayesian technique. A uniform prior distribution …


Characterization Of A Mexican Halloysitic Clay And Behavior In Dry Pressing, Jesus L. Derat Jan 1973

Characterization Of A Mexican Halloysitic Clay And Behavior In Dry Pressing, Jesus L. Derat

Masters Theses

"A Mexican clay, intended to be used as refractory raw material, was identified. Problems encountered in the characterization of halloysitic clays are discussed and emphasis is made on the use of the electron microscope (scanning or transmission type) as a definite evidence of the existence of halloysite due to its unique morphology within the kaolinite group of clay minerals.

Beneficiation of this particular clay was carried out on a small scale hydrocyclone equipment and the results are discussed.

In an attempt to increase the green density in dry pressing of this halloysitic clay, mixtures with grog were prepared using different …


Model Correction For The Formation Of Amorphous Silicon By Ion Implantation, John Robert Dennis Jan 1973

Model Correction For The Formation Of Amorphous Silicon By Ion Implantation, John Robert Dennis

Masters Theses

"ESR has been used to study the formation of an amorphous layer in silicon by ion implantation. The room temperature implants were done at 20 keV with low dose rates. The critical dose was determined as a function of ion mass for six different ion species. Our experimental heavy ion results agree with those found by other ESR investigators at higher energy, but are not the same for light ions. However, our light and heavy ion results agree with electron microscope measurements for low energy implants. An energy-independent model for the formation of amorphous silicon by ion implantation has …


Analysis Of Interferometric Holography In Temperature Measurement, Allan James Reifel Jan 1973

Analysis Of Interferometric Holography In Temperature Measurement, Allan James Reifel

Masters Theses

"An experimental investigation was conducted to evaluate the accuracy and sensitivity of a laser holographic interferometer. Interference fringe patterns of a free convection boundary layer on the surface of a vertical test plate were produced. The plate was heated and designed to produce a linear temperature distribution along its surface.

A thermocouple probe was used to map the temperatures in the boundary layer and these values were compared to temperatures obtained from fringe patterns. Data photographs of the holograms were used in the analysis. The number of fringes obtained were compared to predictions of the Gladstone-Dale Law.

High quality fringe …


Liquid-Liquid Extraction With First Order Reaction : A Mathematical Simulation, Alan Wayne Smith Jan 1973

Liquid-Liquid Extraction With First Order Reaction : A Mathematical Simulation, Alan Wayne Smith

Masters Theses

"Models for mass transfer to droplets based on film theory with first order chemical reaction are proposed and compared with experimental data. The experimental extraction data is available from the work by Andoe (1968). The physical system used was benzene as a continuous phase and water as a dispersed phase with 2-chloro-2- methyl propane the solute diffusing into and reacting in the droplet. This system had a high interfacial tension (31.0 dynes/cm) and droplet Reynolds numbers ranging from 600 to 1345.

The predicted results of this work are in the form of the dimensionless total mass transferred to the droplet …


The Evaluation Of An Activated Sludge Process At Elevated Temperatures, Peter J. Dawson Jan 1973

The Evaluation Of An Activated Sludge Process At Elevated Temperatures, Peter J. Dawson

Masters Theses

"The feasibility of utilizing the thermal energy from an electric power plant to operate an activated sludge process at elevated temperatures (above 40°C) was assessed.

The practicality of using this heat was determined from a heat transfer analysis and the operation of the activated sludge process was evaluated from laboratory studies of a batch process treating domestic and synthetic sewage.

The tank size for a thermophilic activated sludge chamber could be reduced by 40 to 50% as compared to ambient temperatures. For thermophilic processes a temperature of 55°C is recommended because the transition phase between mesophiles and thermophiles is around …


The Effect Of Explosive Charge Length Of Cratering, John M. Mason Jan 1973

The Effect Of Explosive Charge Length Of Cratering, John M. Mason

Masters Theses

"In an attempt to determine the influence of charge length upon cratering, a series of small scale model blasting experiments were conducted in Plexiglas, Hydrostone, mortar and dolomite, using mild detonating fuse as the explosive charge. Single hole blasts were simulated, with the blasthole being drilled normal to one free face and parallel to a second. The resultant craters were photographed and closely studied. Particular attention was paid to effects of variation of charge length and burden upon cratering.

The investigation showed the importance of radial fracturing and the dominance of gas pressure in explosive crater formation from elongated cylindrical …


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

Design Of A High Pressure Fluid Intensifier, James Andrew Kwiatkowski

Masters Theses

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

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


An Experiment To Determine The Coupled Unidirectional Effect Of Wind And Waves On Surface Drift, Rameshchandra C. Shah Jan 1973

An Experiment To Determine The Coupled Unidirectional Effect Of Wind And Waves On Surface Drift, Rameshchandra C. Shah

Masters Theses

"An experiment was conducted to study the coupled parallel and unidirectional effect of wind and waves on surface drift velocity of oil lenses and flexible plastic floats. The experiment was also conducted to study the effect of float width, wave length and air turbulence on the drift velocity of the surface floats. Experiments were also conducted to determine the air flow characteristics of the wind tunnel test section.

Experimental results are presented for a free stream wind velocity from zero to 700 cm/sec; the wave steepness ranged from zero to 0. 069, which is near the maximum steepness for stable …


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

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

Masters Theses

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


A Study Of The Measurement Of Noise Power, Larry Smith Heflin Jan 1973

A Study Of The Measurement Of Noise Power, Larry Smith Heflin

Masters Theses

"In order to compute a power signal-to-noise ratio in the numerical simulation of a communication system, it is necessary to measure the power of the noise present. The required integration can be approximated by many numerical techniques. Five numerical integration methods are available in the user-oriented System/360 Continuous System Modeling Program. Measurements of the power of an additive Gaussian noise waveform are performed, and an analysis of the accuracy of the measurement compared to theoretical values is presented"--Abstract, page ii.


Chemical And Ultrasonic Conditioning Of Water Treatment Plant Coagulant Sludges, Stanley Louis Klemetson Jan 1973

Chemical And Ultrasonic Conditioning Of Water Treatment Plant Coagulant Sludges, Stanley Louis Klemetson

Masters Theses

"The objective of this investigation was to evaluate the use of ultrasonic energy, pH adjustment, and addition of polyelectrolytes in dewatering coagulant sludges. Emphasis was placed on the effects of the ultrasonic power output level and period of conditioning, the chemical conditioning of the sludge, and the type and origin of the sludge. Dewatering is thought to be the most practical approach for reducing the volume of coagulant sludges and efforts are being made to improve their dewatering characteristics.

An experimental system consisting of a magnetically stirred sludge reservoir, sonifier and reaction chamber, polymer feeder, and collection cylinder was developed …


Investigation Of An Energy Absorbing Device For Passenger Safety, Prakash Krishnaswamy Jan 1973

Investigation Of An Energy Absorbing Device For Passenger Safety, Prakash Krishnaswamy

Masters Theses

"Energy absorption by driving an oversized plunger through a longitudinally slit shell has been studied. The characteristics obtained by conducting several runs indicate that such a system could be used for energy absorption and for limiting the force required to drive the plunger through the shell. The characteristics can be readily altered by changing the dimensions of the tube. Details of the experimental set-up have been given.

Such an absorber has been adapted for mitigating injury sustained by the occupants in the interior of a colliding vehicle. Full advantage has been taken of the "Ride down" potential available to the …


An Investigation Into The Degree Of Correlation Between Air Flow Rates, Bacteria In The Air And Post-Operative Infections In Hospitals, Carl Eugene Intag Jan 1973

An Investigation Into The Degree Of Correlation Between Air Flow Rates, Bacteria In The Air And Post-Operative Infections In Hospitals, Carl Eugene Intag

Masters Theses

"Post-operative infections are a recognized problem in the medical and hospital professions. Annual costs and deaths due to infections in the U.S.A. have been estimated at $8-$9 billion and 10,000 lives respectively. The air lS one potential path in transporting contaminants that may cause an infection. Yet, the degree of influence airborne contaminants have in causing infections is a topic of much debate. As a result of the need for more information in this area, this investigation was undertaken to determine the degree of correlation between post-operative infection rates, bacteria in the air, and air flow rates.

Data for the …


Release Of Pollutants From Aquatic Sediments, Lloyd Aldon Hinkle Jr. Jan 1973

Release Of Pollutants From Aquatic Sediments, Lloyd Aldon Hinkle Jr.

Masters Theses

"This study was undertaken to investigate factors governing the release of pollutants from sediments and subsequent effects on water quality. Studies were carried out to: 1) determine the characteristics of selected sediments; 2) determine the level of release of pollutants under batch and fill and draw conditions; 3) determine the effect of temperature and pH on release mechanisms; 4) determine the importance of microbial (uninhibited) release and physio-chemical (inhibited) release processes.

The sediment utilized was from the Missouri River at Jefferson City, Missouri, and the Burgher Branch near Rolla, Missouri. Five environmental conditions to evaluate the effects of pH and …


Adsorption Of Water On Gold, Jean-Marc Louis Deschanel Jan 1973

Adsorption Of Water On Gold, Jean-Marc Louis Deschanel

Masters Theses

"Water adsorption isotherms on gold films were measured with a quartz crystal microbalance. Two gold films were studied: a "dirty" gold film contaminated by approximately one monolayer of carbon, and a "clean" gold film prepared by evaporating gold from a heated tungsten wire under high vacuum.

Water was found to chemisorb on both films according to a Freundlich type adsorption isotherm. Isosteric heats of adsorption were computed from the isotherm data. On the "clean" gold surface the isosteric heat showed a logarithmic decrease with increasing water coverage. The highest measured value for the heat of adsorption was 35 kcal mole …


Treatment Of A Pharmaceutical Waste With The Anaerobic Filter, Norman Dale Dennis Jr. Jan 1973

Treatment Of A Pharmaceutical Waste With The Anaerobic Filter, Norman Dale Dennis Jr.

Masters Theses

"The anaerobic filter is essentially a plug-flow, packed-bed, column type reactor in which the anaerobic bacteria responsible for the waste stabilization are attached to the filter media. This process is a relatively new concept in waste treatment which has been used only in laboratory studies. The objective of this study was to evaluate anaerobic filter performance when used to treat an actual industrial waste under controlled conditions of flow rate, organic strength and temperature.

Four 0.5 cu ft (14.25 l) laboratory filters were operated for 180 days at 35° C using a pharmaceutical waste as the substrate. By varying influent …


An Optical Detector Of Water Droplets Within A Thermal Diffusion Chamber, Duane Burton Bush Jan 1973

An Optical Detector Of Water Droplets Within A Thermal Diffusion Chamber, Duane Burton Bush

Masters Theses

"A technique is investigated for counting water droplets formed in a vertical plate steady flow thermal diffusion chamber designed to count cloud condensation nuclei. The counting technique utilizes light scattering. The light source is a He-Ne laser. The detector is a photomultiplier tube. The technique differs from that used in instruments manufactured by Bausch and Lomb, Royco, Climet, etc., in that the aerosol is not passed through a capillary tube. Instead, the viewed volume is optically defined.

It was found that in the configuration tested, the viewed volume is not well enough defined for use with polydisperse aerosols, although the …


Heavy Metal Analysis Of Stream Sediments In The James River Basin, Missouri, William J. Head Jan 1973

Heavy Metal Analysis Of Stream Sediments In The James River Basin, Missouri, William J. Head

Masters Theses

"A reconnaissance survey of stream sediments using the minus 80 mesh sieve fraction was made at 53 sites throughout the James River basin, Missouri. Sample sites within the 1460 square miles of the basin were chosen at tributary confluences, suspected contamination sources, and known areas of mineralization. Replicates and stream profiles were taken to check for analytical variation and reproducibility of results. Sediment samples were prepared by a hot nitric acid leach method. The sediments were analyzed using an atomic absorption unit to determine Cu, Pb, Zn, and Cd trace metal contents.

Values of selected streams within the basin were …


Corals Of The St. Louis Limestone In The Area Of Calhoun County, Illinois And St. Louis County, Missouri, William Earl Collins Jan 1973

Corals Of The St. Louis Limestone In The Area Of Calhoun County, Illinois And St. Louis County, Missouri, William Earl Collins

Masters Theses

"The St. Louis Limestone and its equivalent formations crop out from Alaska south to Sonora and from Arizona east to Virginia. The St. Louis, in most cases, is fossiliferous and contains numerous species of foraminifers, echinoderms, bryozoans, molluscans, brachipods, arthropods and coelenterates. Algal mounds and mats are common. The rugose coral fauna of the Middle Mississippian (Meramecian) St. Louis Limestone of southern Calhoun County, Illinois and northern St. Louis County, Missouri was studied to determine first what corals were present and second the validity of the names assigned to the previously described species. It was found that the binomen for …