Digital Commons Network^™

Thermal Stresses In A Sphere Due To Local Heating Followed By Complete Cooling, T. S. Chen, K. Thirumalai, J. B. Cheung

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.

Experimental Investigation Of Supporting Wire Interference Effects In The Supersonic Near Wakes Of Slender Bodies., Dale M. Pitt

Masters Theses

"It is generally recognized that the presence of a model support sting i s likely to affect the model's base pressure and wake characteristics. The use of a wire-supported model is usually relied upon to obtain minimum disturbance measurements in the model's wake. Investigations into the disturbances caused by different size supporting wires have been conducted with the use of a 16-degree wedge and cone. The tests were conducted in the University of Missouri-Rolla axisymmetric supersonic wind tunnel at Mach 3.15, and at a Reynolds number of 2.14 X 10⁶ per inch. Pitot pressure traverses were made in the …

Scattering Of Light Atoms From Strongly Periodic Surfaces, J. G. Stoll, Jr., Ralph E. White, J. J. Ehrhardt, R. I. Masel, J. P. Merrill

Faculty Publications

No abstract provided.

Electrochemical Reduction Of Molybdate In The Presence Of Zinc Chloride In Molten Lithium Chloride-Potassium Chloride Eutectic, R. Cvetkovic, Branko N. Popov, H. A. Laitinen

Faculty Publications

Two chronopotentiometric waves were observed for the electrochemical reduction of molybdate in the presence of zinc chloride, with quarter-wave potentials of –1.5V and –1.75V vs. the Pt(II)/Pt reference electrode, respectively. It was observed that an increase in the molybdate concentration causes a decrease of the first transition time indicating a chemical reaction between ZnCl₂ (which is reduced at –1.5V) and Li₂MoO₄ in the melt forming ZnMoO₄ which is sparingly dissociated in LiCl-KCl eutectic. The equilibrium constant for the observed reaction was calculated. X-ray powder diffraction patterns of the reduction product of ZnMoO₄ have been …

A Seismic Investigation Over A Near-Surface Cavern, Richard D. Rechtien, David M. Stewart

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

A field experiment was conducted over a near-surface cavern with the principal objective of obtaining a spatial definition of the associated Cavity Resonance phenomenon, as reported by Watkins et. al. (1967) and by Godson and Watkins (1968). The results of the experiment were inconsistent with those of the earlier investigators in that all seismic events recorded in the vicinity of the cavity, having vertical velocity components, could be readily identified as standard modes of seismic wave transmission. A persistence of strong horizontal motion was observed for late record times. This horizontal motion was consistently oriented parallel to the cavity boundary, …

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 …

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 …

Analysis Of The Stresses Induced In Rock By Rock Splitters., Diogenes De Jesus Chollett

Masters Theses

"The method of solution of the problem of determining the stress and displacement distributions around an unfractured circular hole subjected to nonuniform applied internal pressure located in an infinite plate is developed. Two problems are solved for two different representative boundary conditions. The problem of determining the stress distribution around a circular hole with two symmetric radial cracks subjected to nonuniform applied radial pressure located in an infinite plate is analyzed and developed for further solution"-- Abstract, p. ii

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 …

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 …

Measurement Of Growth Rate To Determine Condensation Coefficients For Water Drops Grown On Natural Cloud Nuclei., A. M. Sinnarwalla, Darryl J. Alofs, J. C. Carstens

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Growth Rate Measurements Were Made for Water Drops Grown on Nuclei in Atmospheric Air Samples Taken in Rolla, Missouri. Rolla, Having a Population of 15,000 and Very Little Industry, is Relatively Free of Urban Pollutants. the Measurements Were Made in a Vertical Flow Thermal Diffusion Chamber at Supersaturations of 0. 5 and 1%. the Time to Grow from Near Dry Radius to the Final Radius (6 to 7. 5 Mu M) Was Measured. If One Assumes the Thermal Accomodation Coefficient is Unity, the Measurements Indicate an Average Value of 0. 026 for the Condensation Coefficient. the Temperature Ranged from 22. …

Insoluble Condensation Nuclei: The Effect Of Contact Angle, Surface Roughness And Adsorption., P. C. Mahata, Darryl J. Alofs

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Condensation of Water Vapor on Various Surfaces Was Studied Experimentally. for Surfaces with an Air-Water Contact Angle Theta Less Than 20 Degree, the Experimentally Determined Values of Critical Supersaturation S//c Agreed with Those Given by the Volmer Theory. at Higher Theta, the Experimental Values of S//c Were Below the Volmer Theory Values. When the Applied Supersaturation Was Less Than S//c, Condensation Was Avoided for Periods as Long as 20 H. It Was Determined Both by Experiment and Theoretical Analysis that the Effect of Surface Roughness is to Decrease S//c Only Slightly. These Results Suggest that Most Insoluble Airborne Particles Are …

Moiré Simulation Of Field-Ion Micrographs, P. D. Ownby, Robert M. Doerr

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

Electroless And Chemical Metal Deposition On Human Tooth Enamel., Richard Doyle Christie

Masters Theses

"Initial investigations have confirmed the feasibility of depositing an adherent metal film onto tooth enamel. Such films might be used as pit and fissure sealants in preventive dentistry, with denture or orthodontic work, as an intermediate substrate with various organic or inorganic restorative materials, or other such areas. The process employs chemical solutions containing ions of the metal to be deposited and suitable reducing agent solutions.

To date, metallic copper and silver films have been plated onto teeth in vitro. The deposits are quite adherent and appear to exhibit the conductivity, crystal structure, luster, hardness, and other chemical and physical …

Crystallization Of A Tetrasilicic Fluormica Glass, W. H. Daniels, Robert E. Moore

Materials Science and Engineering Faculty Research & Creative Works

The crystallization of a tetrasilicic synthetic mica glass of nominal composition K2Mg5Si8O20F4 was investigated at selected temperatures from 560° to 1150°C using DTA, density measurements, electron microscopy, and X‐ray diffraction techniques. Crystallization is shown to occur in 2 stages. (1) Initial structural ordering occurs at ∼600°C, as indicated by a strongly exothermic reaction, an increase in density, and the appearance of X‐ray diffraction lines. (This transformation temperature is related to fluorine content.) (2) The crystal morphology of the glass‐ceramic changes at 900° to 1150°C. A mechanism is proposed for the transformation from amorphous to crystalline structure in this synthetic mica …

Determination Of Oxygen Chemical Diffusion Coefficients In Single Crystal Srtio By Capacitance Manometry, D. B. Schwarz, Harlan U. Anderson

Materials Science and Engineering Faculty Research & Creative Works

The oxidation kinetics of a single crystal of SrTiOs were measured with a tensivolumetric system over the temperature range 700 -975 at 0.03 atm oxygen pressure. The oxidation was found to be oxygen diffusion limited with an activation energy of 14.9 - 1.3 kcal/mole. Combining the kinetic data with relative defect concentration data yielded an activation energy for oxygen self-diffusion of 57 - 16 kcal/mole. The enthalpy of formation of doubly ionized oxygen vacancies was calculated to be 126 - 13 kcal/mol. © 1975, The Electrochemical Society, Inc. All rights reserved.

Mechanism Of Uai3 To Uai4 Transformation, Ling Ping Lee, Hollis P. Leighly

Materials Science and Engineering Faculty Research & Creative Works

The compound, UA14, which forms during the peritectic reaction (Liquid + UA13 → UAI4), has a long needlelike shape and reveals the characteristic morphology of a fishtail when cut along the long axis. When cut perpendicular to the long axis, it shows an internal core of another phase, which has been identified as a primary aluminum solid solution. Because of the interesting relationship between the crystallographic structures of UA13 and UA14, the peculiar UA14 morphology can be explained on the basis of a proposed mechanism. The mechanism of UA13 to UA14 transformation has been identified as shear and diffusion controlled …

Energy Efficiency And Conservation Of Building Hvac Systems Using The Axcess Energy Analysis Computer Program, Ronald H. Howell, Harry J. Sauer Jr.

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

This paper discusses the use of the AXCESS-UMR energy analysis computer program applied to two different buildings. The monthly and yearly energy requirements of many of the commonly used HVAC systems for a single-story multi-zone building are found and compared. Energy conservation techniques are also evaluated for a two-story St. Louis office building.

Control By Code Of Energy Usage In Building Systems, Harry J. Sauer Jr., Ronald H. Howell

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

Space heating, air-conditioning and refrigeration accounts for over 30% of the total energy use in the U.S. ASHRAE Standard 90P, ENERGY CONSERVATION IN NEW BUILDING DESIGN, sets forth requirements for the design of all types of new buildings, covering their exterior envelopes and selection of their HVAC, service water heating, electrical distribution and illuminating systems and equipment for efficient use of energy. This paper reviews the current status, content, and implications of the proposed energy standard and reports some experience with its use.

Centralized Solar Wind Home Heating, Russell Peterson, Duane Cromack

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

In the immediacy of national goals for energy independence, the need emerges to use dialectic methods to diminish the energy consumptive characteristics of the typical home.

At the cutting edge of resourceful progress are the residential developments which embrace alternative and conservative energy techniques. In conjunction with such a planned, low impact community, this paper proposes a cluster-centralized system which utilizes wind energy in combination with solar thermal energy for space and domestic water heating.

A description of the random solar-wind resource embodies a matching problem that in turn reveals the benefits of the combined mode of energy collection. Though …

The Application Of Water Jets In Coal Mining, David A. Summers

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

Water is one of the natural erosion agents which through time has changed the face of the earth. Application of this principle to remove earth and rock by man is a long established technique. This paper briefly describes the changes in technology which have brought the application of water jets from the slow erosion of soil to the point where in Canada some 3,400 tons per shift are currently mined in a coal mine using high pressure water jet technology. The use of water jets has shown sufficient promise that there are several research programs currently being funded by the …

Analogy Between Spinodal Decomposition And Martensitic Transformation, Tetsuro Suzuki, Manfred Wuttig

Physics Faculty Research & Creative Works

The translation of the theory developed for the spinodal decomposition of a supercooled alloy to the language appropriate for the martensitic transformation is carried out. In the spinodal theory, the stability of the alloy with respect to the composition fluctuation is examined, while in the present theory the stability of the crystal with respect to the shear displacement fluctuation, the transverse phonon, is studied. The analogy to the spinodal theory requires the revival of the strain gradient energy term or the couple stress term, the presence of which has been a subject of controversies for a long time since Laval. …

Photoionization Of The 6p32,122 Fine-Structure Levels In Cesium, Kaare J. Nygaard, Robert E. Hebner, James A. Jones, Robert J. Corbin

Physics Faculty Research & Creative Works

The relative photoionization cross sections for cesium atoms selectively excited to the 6P32,122 states have been measured in a triple-crossed-beam experiment. A cesium discharge lamp produced resonant wavelengths of 8521 and 8944 for the excitation process. A Hg-Xe lamp combined with a grating monochromator was used for the actual ionization in the wavelength region from 2500 to 5000. Background counts due to photoionization of ground-state cesium atoms and dimers as well as various surface effects were discriminated against by chopping the excitation light source. The data are compared with results from radiative-recombination measurements in which the fine-structure levels are not …

Improving Embankment Design And Performance: Prediction Of As-Compacted Field Strength By Laboratory Simulation : Interim Report, John L. Peterson

JTRP Technical Reports

No abstract provided.

Further Comments On “Two Counterexamples To Aizerman's Conjecture”, D. Ronald Fannin

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Computer Modeling Of The Statistical Properties Of Transionospheric Scintillation Channels, W. F. Deckelman, Rodger E. Ziemer

Electrical and Computer Engineering Faculty Research & Creative Works

This concise paper shows that a bandlimited bivariate-normal time series is a useful model for the envelope of scintillating radio signals traversing the ionosphere. A software model is presented whose generated time series is compared to an actual block of scintillation data. A comparison of computer-generated and actual scintillation data shows that the fade-duration distribution of the simulated data fits that of the actual data closely through proper choice of model parameters. Copyright © by 1975 The Institute of Electrical and Electronics Engineers, Inc.

Transport Phenomena In Thermally Stratified Boundary Layers, D. W. Pepper, S. C. Lee

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Studies of heat, mass, and momentum transfer are made to analyze the formation of marine fogs in thermally stratified boundary layers in the atmosphere. The governing partial differential equations of continuity, momentum, temperature, and concentration are used to describe the transport phenomena. An additional equation of turbulence energy is introduced to account for the development of the turbulent motions. Simultaneous solution of this system of equations allows the turbulent exchange coefficients to be treated in the same way as all other dependent parameters. Verification of the theoretical approach is made by comparing the numerical predictions with wind tunnel simulations of …

Drag Reduction In Solid‐Fluid Systems, I. Radin, J. L. Zakin, Gary Kent Patterson

Chemical and Biochemical Engineering Faculty Research & Creative Works

Pressure drop measurements were made on a variety of dilute solid‐liquid suspension systems in order to study the effects of particle shape and size, concentration, fluid viscosity, and tube diameter on friction factor. The central objective was to determine under what conditions drag reduction would occur. Copyright © 1975 American Institute of Chemical Engineers

Application Of Voltammetry To Copper Electrodeposition, Louis Francis Toth Jr.

Doctoral Dissertations

"A study was undertaken to determine the feasibility of using voltammetry and scanning electron microscopy techniques to characterize copper deposition from an acid-sulfate electrolyte. The main process variables investigated were temperature and addition agents (chloride ion, glue, separan or thiourea) at different concentrations, over a range of current densities. Cathodes employed were either polycrystalline titanium or copper. Some long-time copper deposits were also made using Ti cathodes and the orientations of these deposits were determined by x-ray diffraction.

Observations of copper crystals produced during voltammetry scans, on a Ti cathode, indicated that a characteristic morphology was associated with each type …