Digital Commons Network^™

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.

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

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 …

Direct Ac Generation From Solar Cell Arrays, Fernando L. Alvarado, Adel H. Eltimsahy

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

Results of the investigation of the performance of solar cells when directly coupled to a conventional three-phase power network are presented. This approach dissociates the electricity production problem from the electric energy storage problem. Extensive studies of the required power inverter are performed. Preliminary simulation results indicate that ac power outputs of better than 90% of the optimum cell power output can be easily achieved by means of a suitably controlled inverter, thereby justifying the elimination of dc loads or local dc electric energy storage devices. It is also shown that the controlling policy for the inverter must depend on …

Status Report On The Callaway Nuclear Power Plant, A. E. Bolan, D. F. Schnell

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

The progress to date of the first nuclear-powered, electric generating plant proposed to be constructed in the state of Missouri is described.

Dynamic Simulation For Regional Energy Studies, B. W. Jones, P. M. Moretti, J. H. Mize

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

A series of models has been developed for regional studies of energy supply- demand systems. The models are based on dynamic simulation of components of the system using equations derived from the technical details of the system. The models contain sufficient detail to make in-depth studies and specific recommendations. The final goal is to include all aspects of regional energy systems from native supplies of energy resources to the economic activities of the region.

To develop a comprehensive model, the system has been partitioned into subsystems, so that a detailed model can be made for each subsystem. The detailed model …

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 …

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 …

Alcohol Assisted Hydrocarbon Fuels: A Comparison Of Exhaust Emissions And Fuel Consumption Using Steady-State And Dynamic Engine Test Facilities, D. J. Bushnell, J. M. Simonsen

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

This paper presents experimental data which exemplifies the differences in emission level testing on internal combustion engines when dynamic engine tests are used instead of steady-state engine tests. A comparison of the two test methods is made using hydrocarbon fuels with varying amounts of methanol. Emissions measured include the nitric oxides, unburned hydrocarbons and carbon monoxide. Emission levels and fuel consumption are reported for the various volumetric percentages of methanol in the fuel.

Of special significance are the different trends the emission levels establish when subjected to a dynamic engine test as compared to the results for the steady-state tests. …

Energy, Environment And Incremental Decision Making, Jeff V. Conopask, Robert R. Reynolds Jr.

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

During the late 1960's and early 70's a variety of environmental/energy oriented legislation was enacted by the Congress. The most important of these acts, the National Environmental Protection Act (NEPA), required that environmental impact statements be filed when various private and public activities have a potential for impacting man and his environment. (17) Impact statement requirements go beyond the currently practiced cost/benefit analysis, which is often just a production (direct) impact assessment. Heretofore, indirect or second round economic and social effects of consequence affecting other national goals were seldom counted.

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

Split-Film Anemometry In A Drag-Reducing Solution, Jack Chosnek

Doctoral Dissertations

"Turbulence measurements were made in the tube flow of mineral oil and a 0.2% solution of polyisobutylene in the same oil. Velocity profiles, axial and radial turbulence intensities, and axial and radial energy spectra were obtained in both fluids using a split-film anemometer probe. In addition, velocity profiles and axial turbulence intensities were obtained in oil using a 0.001-in. cylinder probe, a cone probe and a parabolic-wedge probe. The measurements were made in a one-inch tube at a constant fluid temperature of 30.0°C, in the Reynolds-number range of 4,800 to 50,000.

Four factors influenced the results in a greater manner …

Continuous Purlin Tests, Teoman Peköz

CCFSS Library (1939 - present)

INTRODUCTION The results of the first phase of an experimental investigation are presented in this report. The objective of this investigation is to study the applicability of a theoretical approach developed at Cornell and implemented in a computer program developed by T. Pekoz for Diaphragm Braced Channel and Z-Section Purlins. In this phase of the experimental program three "full-scale" assemblies were tested under simulated wind-uplift loading. In addition, several supplementary tests were carried out to determine various physical parameters utilized in the analytical solution. The reported results are restricted to those tests that have direct bearing on correlating the test …

Bit Penetration Into Rock - A Finite Element Study, Jaw-Kuang Wang

Doctoral Dissertations

"A finite element approach has been developed to simulate bit penetration from bit-rock interaction to chip formation. A mathematical rock failure model, based on a review of the existing literature on rock tests, has been proposed to represent post-failure rock behavior and applied in the penetration simulations. The finite element program has been developed for two dimensional plane strain problems with non-linear material properties, geometrical nonlinearities and fracture. An anisotropic element as well as variable stiffness and stress release methods have been used. An iteration method, using an incremental approach, has been applied for continuous penetration and modifications of material …

A Computer Technique For Calculating The Radiological Consequences Of Pressurized Water Reactor Power Plant Hypothetical Accidents, Charles Francis Gill

Doctoral Dissertations

"A closed form analytical method of calculating the radiological consequences of ten pressurized water reactor (PWR) hypothetical accidents was developed. This methodology was used to develop a computer code, DOSES, to compute the gamma-whole body, beta-skin and iodine inhalation thyroid doses at the site boundary, at the low population zone outer boundary and for control room occupancy for the ten PWR hypothetical accidents. The computer code, DOSES, was developed to operate in the conversational remote terminal mode and to provide a mechanism for producing required information for chapter 15 of PWR nuclear power plant safety analysis reports.

The identification of …

Application Of Laser Holographic Interferometry To The Analysis Of Ground Movement Above Underground Openings, Duk-Won Park

Doctoral Dissertations

"A laser holographic interferometric technique has been recently developed and applied to research in several engineering fields. The technique has many possible applications in earth science and engineering. In this study it was shown that laser holographic ii interferometry can be used to study surface ground movements resulting from subsurface cavity collapse.

One of the most important advantages of the holographic interferometric technique is a rapid three-dimensional displacement measurement of a surface without contact or emplacement of instruments. The surface does not have to be flat or smooth allowing deflection contours to be generated on a granular surface. applied in …

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 …

Development Of Helicopter Flight Path Models Utilizing Modern Control Techniques, Alfred Fermelia

Doctoral Dissertations

"The nonlinear set of equations which represents helicopter motion are linearized about a prescribed nominal state. Once the linearized system is obtained it is validated by comparing the output of the nonlinear system to that of its linearized counterpart. Having obtained a linear model, linear system theory may then be applied in order to investigate the stability and control characteristics of the aircraft.

General techniques for simulating helicopter pilot response for inclusion in a flight path simulation program have been devised. To provide the desired flight goal, a nominal flight trajectory is obtained from an existing nonlinear model. With this …

Excitation Of Source Electromagnetic Waves At Microwave Frequencies Using Optical Techniques, M. Davarpanah

Doctoral Dissertations

"The coupling efficiencies for the excitation of surface electromagnetic waves (SEW} for both the prism and the grating techniques have been studied experimentally in the microwave frequency range. The grating experiments included studies of the SEW coupling efficiencies as functions of the frequency, the angle of incidence, the grating constant, the number of grating bars, and the position of the grating bar at which the maximum radiation field of the antenna was aimed. For the prism coupling technique, the coupling efficiency was studied as functions of the angle of incidence, the aiming point of the transmitting antenna on the prism …