Engineering Commons^™

The Influence Of Oxygen Activity On Sintering Of Strontium Doped Lanthanum Chromite., Leslie Groupp

Masters Theses

"The influence of oxygen activity upon the sintering of lanthanum chromite (La_1-xSr_x CrO₃) with x ranging from Oto 0.2 was investigated using chemically prepared powders of <0.1 microns particle size. The results show that at a temperature of 1740 ° C densities of >92% of theoretical could be achieved if the oxygen activities were maintained in the 10^-11 to 10^-12 atm. range. If oxygen activity exceeds 10^-10 atm., densities of not >80% theoretical could be obtained. For the compositions studied, room temperature X-ray analysis of both the starting powders and sintered compacts show the compositions to be orthorhombic and single phase. The ambient lattice parameters and resistivity measurements decreased …

Dynamic Testing Of Anchors Buried In Dry Sand., Jim Lee Hillhouse

Masters Theses

"The dynamic pullout resistance of anchors was investigated through the use of model testing under controlled conditions. The soil used for the model tests was a dry sand compacted to a uniform relative density of approximately 92 percent. The dynamic loading of the anchor-soil system was applied by a mechanical device, which applied a specific amplitude and frequency of dynamic load to the anchor-soil system.

The dynamic testing of the anchors consisted of two phases. First, an initial static load was applied to the anchor. Second, a dynamic load was superimposed over the initial static load. The load applied to …

Ground Control Evaluation Of The Sahara No. 20 Mine Marion, Illinois., Marvin E. Adam

Masters Theses

"Roof falls in coal mines are the single greatest cause of mining accidents in the U.S. today. For this reason it is imperative that the mechanism of roof failures be identified. An investigation funded by the U.S. Bureau of Mines was initiated in 1970 to determine the factors influencing the deterioration of coal mine roof shale. This thesis was a portion of the investigation that concentrated on the Sahara Coal Company underground mine No. 20 near Marion, Illinois.

The regional geology was studied to determine if geological discontinuities might be an influencing factor on roof falls at the Sahara 20 …

A Study Of Trace Organic Emissions In Mining And Milling Wastewaters In The New Lead Belt Of Southeastern Missouri., Alan James Callier

Masters Theses

"The primary objective of this study was to evaluate the trace organic contributions by two lead and zinc mining and milling operations in Southeastern Missouri. A secondary objective was to evaluate a reverse osmosis-solvent extraction method for use in recovering trace organics.

Trace organics were recovered in the first phase of the study following procedures as outlined by the American Society of Testing and Materials (ASTM), with chloroform and benzene being used as the solvents. The data indicated that the milling waste contained a larger concentration of trace organics than the excess mine water. Furthermore, it was shown that recycling …

An Experimental Study Of Mass Transfer To Droplets In Aqueous Polymer Solutions., Richard Gerard Schafermeyer

Masters Theses

"Instantaneous and time-average mass transfer coefficients for 1 the free-fall period was obtained for transfer of iodine from nonNewtonian continuous phases to carbon tetrachloride drops. The nonNewtonian continuous phases were aqueous solutions of carboxymethyl cellulose and carboxy polymethylene. Although a few exceptions were found, the continuous phase mass transfer coefficients were, in general, found to decrease with increasing time of drop contact. Comparisons of the experimental data to theoretical relations showed that changes in drop internal circulation probably occurred for that data which showed a time effect for the mass transfer coefficient. Several explanations for the time effect were offered, …

A Study Of Product Inhibition In The Reaction Of P-Nitrophenyl- Α - D - Glucoside Catalyzed By The Enzyme Glucoamylase I., Mark L. Dickhaus

Masters Theses

"The entire time course of the hydrolysis of p-nitrophenyl-a-D-glucoside by the enzyme glucoamylase I was followed spectrophotometrically. Using time versus absorbance data the constants in the Michaelis-Menten equation were determined. The effect of the addition of product to the initial reaction mixture and the effect of solvent and temperature were determined. It was found that product produced during the reaction did not have the same effect upon the rate as did product added initially to the reaction mixture. The presence of substrate caused the enzyme to acquire protection against inhibition by the product"-- Abstract, p. ii

Decoupled Explosive Charge Effects On Blasting Performance, Roberto Ucar

Masters Theses

"This investigation was performed to determine the burden at which hard rock would break utilizing decoupled and unstemmed charges when the free surface parallel to the borehole was the wall of an open hole. This open hole was created by burn cuts and by drilling holes of 7-7/8 in. and 12 in. diameter. Additional tests were performed using partially stemmed charges where the stemming was the same size as the explosive charge.

The explosive used was a 0.75 lb. slurry charge, 1.5 in. diameter and 10 in. long. The diameter and depth of the borehole were 2 in. and …

An Optimization Method For Scheduling Nuclear Reactor's Refueling St. Louis County, Missouri., Abbas Razavi

Masters Theses

"This paper describes a method to optimize the refueling schedule of the nuclear units. The method finds a mid-range (five to ten years) optimum refueling schedule by varying the refueling date of the nuclear units. The cycles of the nuclear units are the variable parameters, with fuel enrichment and quantity being fixed.

An empirical technique is used to calculate the nuclear fuel cost. Seasonal constraints are taken into account, and no nuclear unit will be shut down while another is down"-- Abstract, p. ii

An Examination Of The Adaptive Random Search Technique., Mark William Heuckroth

Masters Theses

"Random search procedures have recently been successfully applied to the optimization o f a variety of chemical engineering problems, including optimization of chemical processes by flow sheet simulation. These procedures represent the independent variables as random variables described by probability distributions. The adaptive random search procedure centers the distribution for each variable about the best search point found and examines this region for a better point. Thus, this technique has the ability of continuously moving the search region toward the optimum, which is particularly advantageous in following constraints.

This study examines the efficiency of the adaptive random search technique as …

Computer Simulation Of Radiation Effects In Fe₃Al By Using Alternating Direction Implicit Numerical Techniques., Dean Lewis Tibbitts

Masters Theses

"An analysis was conducted to see if the alternating direction implicit (a.d.i.) numerical technique could be applied to a many-body dynamical radiation damage model.

The computer program which resulted was named ADI. It was numerically stable for small time steps used in conjunction with low ev knock-ens. It was also able to relax the a toms in the system simultaneously in the implicit direction. However, an existing explicit computer code, which was to be replaced by ADI, proved to be more numerically stable and about 40% faster"-- Abstract, p. ii

A Study Of Stability Of Ac And Dc Transmission Lines Operated In Parallel., Tzyy-Cheng Wang

Masters Theses

"This thesis is concerned with the analysis, optimization and simulation of parallel operation of ac and de transmission lines.

An introduction and literature review are provided to give background information on how the parallel operation should be considered. The parallel system is analyzed, and the state equation is derived for determining the stability limit. The optimization of the control law U = Fx is determined by a standard quadratic cost function. Prefault, during fault and postfault situations in the parallel operation has been simulated by Continuous System Modeling program. Some comparison and comments are made between 1 ac, 1 de …

Variables Affecting The Rate Of Solution Of Mold Inoculants In Cast Iron, Jose Osorno Fonnegra

Masters Theses

"The purpose of this investigation was to measure the effectiveness of an inoculant alloy reacting with molten cast iron in a reaction chamber properly located in the gating system.

The chemical composition of the gray iron was held constant while several metallurgical factors were varied to produce test samples with different cementite thicknesses. These chill depths were measured as an indication of the inoculation effectiveness.

Appreciable differences in chilling tendency were observed within the different variables studied. The results indicate that pouring temperature, as well as the other variables studied, are of considerable importance when dealing with inoculation of gray …

Documentation Of A Short Circuit Program For Fault And Protection Studies., Alejandro Gonzales

Masters Theses

"For a given power system of no more than 100 buses and 400 line ends (source lines have one line end, radial lines have one line end and regular lines have two) a digital computer program is presented which determines the short circuit currents needed to implement a protective relaying design, The program uses the ZBUS method of analysis and calculates the currents at all buses, searches for the maximum and minimum values of the current contributed by the lines connected to the faulted bus under normal conditions (all lines in) and under single and double line outages. Maximum and …

Denitrification Of A Synthetic Waste With A Submerged Filter, Dominic Joseph Grana

Masters Theses

"The facultative anaerobic submerged filter is a plug flow, packed bed, column type reactor in which the facultative microorganisms responsible for nitrate reduction are attached to the filter media. The objective of this study was to evaluate filter performance and the kinetic equations of the process under variable conditions of flow rate, nitrate nitrogen concentration, and organic loading.

Two 0.5 cu ft (14.25 1) laboratory filters were operated for 144 days at 35°C using a synthetic waste as the substrate. Filter media consisted of smooth quartzite stone, 1 to 1.5 in. (2.54-3.82 cm) in diameter. Each filter had a porosity …

An Organizational Structure For A Highway Agency., Frank L. Carroll

Masters Theses

"Highway agencies in the past have been organized to give primary consideration to economic factors. Th e National Environmental Policy Act of 1969 changed this concept by requiring all states to reevaluate their highway organizations in order to ensure that social and environmental factors, as well as economic factors, are considered.

Various state highway organizations are analyzed to determine the way in which consideration is given to the social, economic and environmental effects of design, and a model organizational structure for a highway agency is developed.

Because considerable difference exists in the ways in which the states have approached the …

An Experimental Model For Predicting The Commodity Futures Market., C. E. Roy Francis

Masters Theses

"Trading of· commodity futures contracts is one of the purest forms of speculation available today. Inherent is the risk of substantial losses. In an effort to reduce these risks, this research was undertaken.

As a result, a computer program was developed to forecast the prices of commodity future contracts on a daily basis. The program employs the Monte Carlo Technique of simulation and provides expected values for the next trading day.

During the development and testing of the prediction model. various trading techniques were also tested. A trading technique utilizing the difference between the forecasted price and the actual price …

Effect Of Temperature, Aging, And Composition On Phase Development In The System Al₂O₃-P₂O₅-H₂0., John Allan Middleton

Masters Theses

The chemical and physical conditions for the formation of various phases of aluminum phosphate were studied. Mixtures of Al₂O₃ and H₃PO₄ were aged in sealed containers and examined for phase development by X-ray diffraction. The results revealed the aging of samples to be a critical process for the formation of equilibrium phase assemblages at low temperatures, Initial composition becomes important as equilibrium is neared and at elevated temperatures when the molar ratios of Al₂O₃, P₂O₅, and H₂O determine what phases will be formed. Temperature …

Performance Evaluation Of Linear Systems Using The Fast Fourier Transform., Larry Leonard Lamano

Masters Theses

"In order for a computer simulation of a communication system to yield useful and meaningful results, a method for determining system performance is often essential. The computer postprocessor, described in this thesis, allows accurate determination of the mean-square-error induced by the system being simulated and the noise power at any point in the system.

Measurements of the mean-square-error induced by a system due to amplitude distortion, phase distortion, and amplitude and phase distortion, along with measurements of the power in a Gaussian noise waveform are performed. The values obtained using simulation are compared to the corresponding theoretical values in order …

Characterization Of Two Mexican Raw Dolomites For Refractory Brick Production, Rodolfo Trevino Cantu

Masters Theses

"Two Mexican dolomites were characterized in order to discover their suitability for production of refractory brick.

The results were compared with other dolomites from American Companies. Some samples were burned in a gas fired Laboratory Furnace and others were obtained in the burned state after processing in Industrial Rotary Kilns.

The characterization procedures included X-Ray Diffraction, Scanning Auger Microprobe, DTA and TGA techniques, Chemical Analysis and Bulk Density measurements.

The procedure to control the quality of the dead-burned dolomite at the industrial level was established taking as the main criteria, bulk density, hydration susceptibility, and impurity levels"--Abstract, page ii.

Effects Of Colloidal Materials And Polyelectrolytes On Carbon Adsorption In Aqueous Solution., Jack Taylor Garrett Jr.

Masters Theses

"The purpose of this study was to investigate the effect of certain colloidal materials and long-chain polyelectrolytes on the adsorption efficiency of some selected activated carbons which were manufactured from both coal-based and lignite-based materials. Phenol was used as the adsorbate to determine the adsorption efficiency.

At the beginning of the study, four brands of activated carbon (i.e. Filtrasorb 400, Darco, Norit, and Witco 256) were tried, based on the preliminary adsorption data, two activated carbons were subsequently selected for use throughout the entire study. These were Calgon's Filtrasorb 400 and American Norit's Norit activated carbons. The former represents a …

The Availability And Development Of An Automated Accounting System For Small Businesses., Margy Rice Beckmeyer

Masters Theses

"A good accounting system is a very essential part of the successful operation of a small business but is often lacking. Therefore, the objective of this research is to furnish a general automated accounting system suitable for use by the small business firm.

To determine the feasibility, a statistical survey was made to evaluate the availability of automated accounting systems now available to small business. The results of the survey suggest that computer systems are presently available to small business firms at economical prices, but to minimize cost the small firm may need to supply its own accounting program.

The …

Planned Unit Development: A Comprehensive Analysis Of A New Approach To Community Living., John Raymond Weese

Masters Theses

"Undeveloped land in America has been one of our most cherished natural resources for many years. Yet, land development has often been haphazard and extremely wasteful.

This paper presents a comprehensive analysis of one particular method for developing land which utilizes land efficiently, but which also respects the natural characteristics of a land development site. The Planned Unit Development process is such a method, and it is the subject of this paper.

The Planned Unit Development concept is an outgrowth of the planned community concept which has existed for many years. However, only recently has the Planned Unit Development concept …

The Design Of A Hydraulic Jet Coal Cutting Head., Rodney Steven Eck

Masters Theses

"The use of high-pressure water as a tool for cutting coal is discussed. A proposed longwall coal mining machine utilizing oscillating water jets to cut coal is presented. Apparatus for experimentation using high pressure water involving single and dual oscillating jets was designed, constructed, and tested. The design of the cutting head for the proposed mining machine is considered"-- Abstract, p. ii

A Study Of Trace Organics And Trace Organic-Bound Metals In Raw And Finished Waters., Robert Lee Stewart

Masters Theses

"The main objectives of this study were: (a) to prepare a comprehensive review and evaluation of the literature pertaining to trace substances, with emphasis on their status in water supplies, health effects, and fate in treatment; ( b) to establish the methodology needed for measuring trace metals in trace organic substances; and (c) to determine the metal content of organic extracts recovered from surface, subsurface, and finished waters.

Raw and finished water was obtained at the Sedalia, MO, water treatment plant, and 5 sources were sampled (3 surface, 1 well, 1 plant-treated). The 0-CA* and SEM procedures were employed to …

Ionic Thermal Current In Sodium-Rubidium Silicate Glasses., Chi-Ming Hong

Masters Theses

"The ionic thermal current (ITC) method has been employed to study alkali ion motion in a sodium silicate glass and two sodium-rubidium silicate glasses over the temperature range 110 ° K to 400 ° K. T wo peaks and three peaks were observed in a l.0Na₂O-3.0SiO₂ glass and a 0.75Na₂O-0.25Rb₂O-3.0SiO₂ glass, respectively. Only one peak and a high temperature shoulder were observed in the 0.50Na₂O-0.50Rb₂O-3.0SiO₂ glass. These peaks were attributed to orientation and space charge polarization with each peak associated with a particular movement of the sodium …

Image Detection In Signal Dependent Noise., Robert D. Laramore

Masters Theses

"This thesis deals with the detection of two-dimensional signals in the presence of noise, including signal dependent noise. The object to be detected and the background are assumed known a priori. A decision rule based on a likelihood ratio test is obtained and the associated probabilities of detection and false alarm are evaluated. This is done first in general terms, where neither the form of sampling nor the model used for noise is specified. Then results are obtained for three examples: Poisson noise, signal dependent Gaussian noise, and binomial noise. Finally, the degradation resulting from a point spread function is …

The Development Of A Selection Model For Coal Conversion Processes., Karen Aldridge Dollar

Masters Theses

"Present research endeavors involving coal conversion technology have encompassed comparisons of the processes on the basis of economics or efficiency. These comparisons lack completeness because many intangible factors pertinent to the evaluations of the processes have been ignored.

A model has been developed to aid in the selection of the optimum coal conversion process for a given situation. The model includes a method for the evaluation of quantifiable factors which affect the decision-making procedure, and also includes methods by which the non-quantifiable factors which are important to the situation may be evaluated. This is a more complete form of decision-making …

The Spheriodization Of Tool Steels., Siri Ram Rai

Masters Theses

"Four different tool steels--AISI 01, Sl, A9 and Tl5--were obtained in the 1/2-inch diameter hot rolled and air-cooled condition from the steel mill. The lower critical temperatures of these steels were determined. The spheroidization of each steel by three different spheroidizing procedures was evaluated with the use of hardness testing and metallographic techniques. Isothermal annealing completely spheroidized each steel yielding coarse carbides and low hardness. Cyclic annealing was an effective spheroidization procedure only for 01 and Tl5 steels. Hardening and tempering resulted in rather fine spheroidized structures in these steels. The total time consumed to produce the best spheroidized structures …

Wastewater Treatment With Activated Carbon., Chia-Soui Joseph Lu

Masters Theses

"The objectives of this study was to determine the capabilities of selected types of activated carbon as an adsorbent for the removal of organic materials from municipal wastewater and sludges. The organic sources included primary and secondary clarifier effluent, blended sludge, and digester supernatant. Two other organic sources, glucose and alanine, were also examined to determine their removal from aqueous solution by activated carbon adsorption.

The organic impurities, in terms of chemical oxygen demand (COD), were reduced from 68 mg/1 in the primary effluent and 35 mg/1 in the secondary clarifier effluent to approximately 15 mg/1 for both. However, the …

Ultrasonic Instrumentation And The Dynamic Evaluation Of Asphalt-Aggregate Mixtures., John Edward Hill

Masters Theses

"Ultrasonic probes have been constructed for use in the dynamic and nondestructive testing of asphaltic concrete specimens. The probe systems exhibited characteristics superior to the solitary ii use of their main components, the piezoelectric crystals. The probes have the advantages of the reduction of ringing time, the concentration of ultrasound in one direction, the elimination of "noise" due to unshielded connections and the increased durability of the probe system.

The probes constructed were used in a limited testing program. Compression and transverse wave velocities in the specimens tested were measured simultaneously. Sample conditions suitable for maximum wave velocity corresponded to …