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Strain Effects On The Esr Spectrum From Antimony Donors In Germanium, Edward Boyd Hale, John R. Dennis, Shih Hua Pan Jan 1975

Strain Effects On The Esr Spectrum From Antimony Donors In Germanium, Edward Boyd Hale, John R. Dennis, Shih Hua Pan

Physics Faculty Research & Creative Works

The electron-spin-resonance spectra from surface-strained (but not externally stressed) antimony-doped germanium are investigated in detail. Experimental data are given for the linewidth, line asymmetry, and line-shape reversal feature as well as for the changes in donor concentration, temperature, and surface conditions. The donors of interest occur in a surface layer several microns thick. A theoretical analysis is based on the Kohn-Luttinger formulation for a shallow donor electron, which is forced by surface strain to predominately occupy a [111] conduction-band valley minimum. A substantial distribution in strain among the donor sites is necessary to account for the line-structure features. These features …


Crystallization Of A Tetrasilicic Fluormica Glass, W. H. Daniels, Robert E. Moore Jan 1975

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 Jan 1975

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 Jan 1975

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 …


Photoionization Of The 6p32,122 Fine-Structure Levels In Cesium, Kaare J. Nygaard, Robert E. Hebner, James A. Jones, Robert J. Corbin Jan 1975

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 …


Double Reflection Dips From Grating Ruled Semiconductors, L. F. Teng, Ralph William Alexander, Robert John Bell, B. Fischer Jan 1975

Double Reflection Dips From Grating Ruled Semiconductors, L. F. Teng, Ralph William Alexander, Robert John Bell, B. Fischer

Physics Faculty Research & Creative Works

The Double Reflectivity Dips, Previously Observed by Fischer Et Al. and Anderson Et Al., Which Appeared in the Reflection Spectra of Grating Surfaces On, the Te‐doped Semiconductors GaAs and InSb Around Both the Plasmon and Phonon Frequencies Have Been Measured in More Detail. in the Plasmon Region, Several Possible Explanations of the Phenomenon Are Discussed, But the Favored Explanation Involves Surface Damage. a Simple Two‐region Reflectivity Equation Checked with a Rigorous Grating Theory is Proposed and is Shown to Fit the Data Well. Copyright © 1975 WILEY‐VCH Verlag GmbH & Co. KGaA


Further Comments On “Two Counterexamples To Aizerman's Conjecture”, D. Ronald Fannin Jan 1975

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 Jan 1975

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.


Energy, Environment And Incremental Decision Making, Jeff V. Conopask, Robert R. Reynolds Jr. Jan 1975

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 Jan 1975

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


Bit Penetration Into Rock - A Finite Element Study, Jaw-Kuang Wang Jan 1975

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 …


Application Of Voltammetry To Copper Electrodeposition, Louis Francis Toth Jr. Jan 1975

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 …


The Noble Gas Record Of Terrestrial And Meteoritic Samples, Edward W. Hennecke Jan 1975

The Noble Gas Record Of Terrestrial And Meteoritic Samples, Edward W. Hennecke

Doctoral Dissertations

"Analyses of tellurium and xenon in a telluride ore from Kalgoorlie, Australia resulted in the following conclusions:

  1. The ratio of the double beta-decay half-life of 128Te relative to that of 130Te is 1.6 x 103
  2. The double beta-decay half-life of 130Te is 1.0 x 1021 years.
  3. The measured half-lives are consistent with values predicted for a second order process of ordinary beta-decay that occurs with the emission of two neutrinos.

A study of noble gases in Thailand tektites provided the following information on the history of these objects:

  1. The isotopic compositions of nonradiogenic Ne, Ar, …


Performance Evaluation Of Linear Systems Using The Fast Fourier Transform., Larry Leonard Lamano Jan 1975

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 …


Reflected Surface Waves From A Vertical Discontinuity., Jesus Manuel Aboud Jan 1975

Reflected Surface Waves From A Vertical Discontinuity., Jesus Manuel Aboud

Masters Theses

"Surface waves generated in the field by small explosions were observed along lines parallel and perpendicular to a vertical discontinuity in a surface layer. Three types of wave particle motion were observed in waves incident on the discontinuity: retrograde, progressive, and shear (SH). Waves of the last two types were intense enough to observe a reflection, permitting calculation of reflection coefficients. The results demonstrate the feasibility of using reflection measurements to locate a discontinuity such as a fault zone"-- Abstract, p. ii


Phase Equilibria Near The Solidus Temperature For Iron-Rich Fe-Cu-C Alloys., Kenneth L. Metz Jr. Jan 1975

Phase Equilibria Near The Solidus Temperature For Iron-Rich Fe-Cu-C Alloys., Kenneth L. Metz Jr.

Masters Theses

"The effect of copper on the solidification temperature of graphite-saturated iron-rich alloys was determined with the use of cooling curves. The ternary invariant temperature for the alloy was found to be 1172°c with the use of heating curves. At 1172°c, graphite, austenite, an iron rich liquid, and a copper-rich liquid are in equilibrium. The composition of the metallic phases was determined by weight gain, chemical analysis, and the electron microprobe. In addition, the composition of the iron-rich liquid was calculated from thermodynamic data. Isothermal sections of the iron-rich corner of the system were constructed for several temperatures in the range …


Verifications Of The Kalman Conjecture For Irrational Transfer Functions, D. Ronald Fannin, Charles E. Connelly Jan 1975

Verifications Of The Kalman Conjecture For Irrational Transfer Functions, D. Ronald Fannin, Charles E. Connelly

Electrical and Computer Engineering Faculty Research & Creative Works

The sufficient conditions for the Kalman conjecture to be satisfied given by Fannin and Rushing [1] are relaxed in such a way as to allow their approach to be applied to irrational transfer functions. Specific results for a class of systems containing transportation lag are presented. © 1975, IEEE. All rights reserved.


The Missouri Miner, November 21, 1974 Nov 1974

The Missouri Miner, November 21, 1974

The Missouri Miner Newspaper

No abstract provided.


The Missouri Miner, October 24, 1974 Oct 1974

The Missouri Miner, October 24, 1974

The Missouri Miner Newspaper

No abstract provided.


The Missouri Miner, October 17, 1974 Oct 1974

The Missouri Miner, October 17, 1974

The Missouri Miner Newspaper

No abstract provided.


Effect Of Molecular Angular Momentum On The Thermal Conductivity Of A Multicomponent Gas Mixture, Louis Biolsi Jr., Edward Allen Mason Jul 1974

Effect Of Molecular Angular Momentum On The Thermal Conductivity Of A Multicomponent Gas Mixture, Louis Biolsi Jr., Edward Allen Mason

Chemistry Faculty Research & Creative Works

The effects of molecular angular momentum (spin polarization) on the thermal conductivity of a multicomponent gas mixture are considered. The Wang Chang-Uhlenbeck approach to the kinetic theory of gases with internal states is used. Formal results are obtained for the thermal conductivity of a gas mixture of uniform composition. These results are given in terms of the quantum mechanical degeneracy-averaged cross section.


Eikonal Distorted-Wave Calculation For The Excitation Of H By He, Jerry Peacher, Richard H. Shields Jun 1974

Eikonal Distorted-Wave Calculation For The Excitation Of H By He, Jerry Peacher, Richard H. Shields

Physics Faculty Research & Creative Works

The eikonal distorted-wave Born approximation developed recently by Chen, Joachain, and Watson is applied to hydrogen excitation by helium impact in the intermediate-energy range. The differential and total cross sections for the excitation of the hydrogen atom to the 2s, 2p±, or 2p0 state by helium impact are presented. These results are compared to experiment and previous calculations. The differential cross section for the excitation of hydrogen to the 2s state compares well with the experimental data of Thomas and Sauers in shape and slope, but has a discrepancy in magnitude.


The Missouri Miner, May 01, 1974 May 1974

The Missouri Miner, May 01, 1974

The Missouri Miner Newspaper

No abstract provided.


The Energy Problem -- Crude Oil, J. A. Marshall Apr 1974

The Energy Problem -- Crude Oil, J. A. Marshall

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

This paper discusses the national energy problem as it affects the demand for and availability of crude oil. Forecasts of energy demands to 1990 have been made based on population trends and changing life styles in the USA. Projections of energy supplies show a rapidly increasing gap between supply of crude oil and demand for crude oil from the early 1970's through 1990. The need for imported crude oil to supply the forecast deficit is discussed. The political and economic implications of these imports are also discussed. The need for refineries, port facilities, tankers, and pipelines are presented. Finally, recommendations …


Status And Outlook For Energy Conversion Via Fuel Cells, John P. Ackerman Apr 1974

Status And Outlook For Energy Conversion Via Fuel Cells, John P. Ackerman

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

Fuel cells have the potential of providing good solutions to a variety of energy-related problems. As our supplies of conventional fossil fuels are depleted, their cost will rise, and there will be increasing difficulty in obtaining certain premium fuels at any price. It behooves us, then, to use our remaining reserves of fuels as efficiently as possible. Energy conversion via fuel cells represents one of the best ways to achieve this goal, because it is possible, simultaneously, to obtain more work and less pollution from a dollar's worth of fuel with a fuel cell than with any other device.


Bellamy Field Tests: Recovery Of Medium Gravity Crude Oil From Missouri Tar Sands By Counterflow Underground Burning, J. C. Trantham Apr 1974

Bellamy Field Tests: Recovery Of Medium Gravity Crude Oil From Missouri Tar Sands By Counterflow Underground Burning, J. C. Trantham

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

In the current energy shortage, the heavy oil and tar sands of the United States are assuming critical importance. This is true for at least two reasons: first, they constitute a major resource, amounting to some 150 billion barrels in place; and second, their where-abouts is known -- exploration will not contribute to the lead time required for bringing these resources into the national energy picture. Moreover, many of the technological problems have been solved. The delay in producing these heavy oil and tar deposits is due primarily to economics.


Are Nuclear Shipments Really Safe?, William A. Brobst Apr 1974

Are Nuclear Shipments Really Safe?, William A. Brobst

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

The transportation of nuclear materials is on the increase. Although nuclear shipments are only a very small fraction of the Nation’s hazardous materials shipments, they attract a great deal of public attention. Shipments of spent nuclear fuel and nuclear wastes are a particular concern.

One of the many fears that people have about nuclear energy is the possibility that a nuclear shipment might somehow go awry and cause a serious public hazard. Primarily, they are worried that a shipment of spent reactor fuel or highly radioactive waste could be involved in a serious rail or highway accident and dump its …


Uniroyal's Approach To Energy Management, J. C. Madigan Apr 1974

Uniroyal's Approach To Energy Management, J. C. Madigan

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

Uniroyal makes selected consumer and industrial products including chemicals, plastics, and rubber articles in 90 plants worldwide. About 90% of raw materials are petroleum-based and about $40 million will be spent on energy in 1974.

Energy management includes centralized monitoring and feedback of usage per unit of production at all factories; energy audits; educational programs; suggestion systems; operational, maintenance, and capital investment programs. Specific items are detailed. Organization places responsibility on Divisional Coordinators backed by President and Divisional Vice Presidents, coached and assisted by Corporate Coordinator and Engineering Specialists. Results in 1973 were very encouraging.


A Technique For Improving Stability Of Petroleum Reservoir Simulation Models, M. D. Arnold, T. C. Wilson, A. Herbert Harvey Apr 1974

A Technique For Improving Stability Of Petroleum Reservoir Simulation Models, M. D. Arnold, T. C. Wilson, A. Herbert Harvey

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

Computational instability may occur in the mathematical simulation of hydrocarbon reservoirs when small inaccuracies in the calculated pressures cause loss of diagonal dominance in the matrix of coefficients. The problem can be resolved by the use of a more precise technique for computation of pressures. However, this stability problem is still troublesome to users of certain types of reservoir simulators. A computational technique which has been found effective in resolving the problem is presented.


Diffusion Coefficients Of N-Heptane And N-Decane In N-Alkanes And N-Alcohols At Several Temperatures, James W. Moore, Robert M. Wellek Apr 1974

Diffusion Coefficients Of N-Heptane And N-Decane In N-Alkanes And N-Alcohols At Several Temperatures, James W. Moore, Robert M. Wellek

Chemical and Biochemical Engineering Faculty Research & Creative Works

The diffusion coefficients of the solutes n-heptane and n-decane were measured in the series of alkane solvents n-hexane through n-decane and in the alcohol solvents n-hexanol and n-heptanol. Mutual and self-diffusivities in most cases were measured at the temperatures of 20°, 25°, 30°, and 40°C. Concentrations of the diffusion species were in the infinitely dilute region. An unsteady state porous frit technique was used with carbon-14 tagged diffusion species. The diffusion coefficients measured were compared with various liquid diffusivity prediction correlations. © 1974, American Chemical Society. All rights reserved.