Physical Sciences and Mathematics Commons^™

Electron Impact Autoionization In Heavy Alkali Metals, Kaare J. Nygaard

Physics Faculty Research & Creative Works

Autoionizing levels in cesium, rubidium, and potassium have been studied by electron impact in a crossed-beam apparatus. Comparisons are made with the binary-encounter calculations of Roy and Rai. The effects of autoionization and inner-shell ionization have been overestimated in the theory. © 1975 The American Physical Society.

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. …

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 …

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 …

A Piagetian Approach To General Chemistry, Donald W. Beistel

Chemistry Faculty Research & Creative Works

No abstract provided.

Mixed Nonderivative Algorithms For Unconstrained Optimization, Roger Ellis Lessman

Doctoral Dissertations

"A general technique is developed to restart nonderivative algorithms in unconstrained optimization. Application of the technique is shown to result in mixed algorithms which are considerably more robust than their component procedures. A general mixed algorithm is developed and its convergence is demonstrated. A uniform computational comparison is given for the new mixed algorithms and for a collection of procedures from the literature"--Abstract, page ii.

Surface Electromagnetic Waves On Layered Systems With Damping, C. A. Ward, Ralph William Alexander, Robert John Bell

Physics Faculty Research & Creative Works

The Dispersion Curves, Propagation Distances, and Poynting Vectors of Surface Electromagnetic Waves Propagating on a System of Cu-Cu2O-Air with Variable Film Thickness Have Been Calculated using the Full Dispersion Realation Including Damping. Double-Dip Structure in the Propagation Distance for Intermediately Thick overlayers, the Shifting of One Dip Below ΣTO, and the Presence of the Other Dip at ΣLO Are Explained in Terms of Features of the Dispersion Curve. the Complete Poynting-Vector Calculations Show that Predictions of Field Bunching at ΣLO Are Probably in Error. © 1975 the American Physical Society.

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

Multimedia Dispersion Relation For Surface Electromagnetic Waves, C. A. Ward, K. Bhasin, Robert John Bell, Ralph William Alexander, I. Tyler

Physics Faculty Research & Creative Works

We Have Derived a General, N-Media Dispersion Relation for Surface Electromagnetic Waves Propagating on Isotropic Layers with Complex Dielectric Functions. the Equation is Presented in a Convenient, Compact Form for Ease of Application. Copyright © 1975 American Institute of Physics.

Locating The St. Louis Urban Plume At 80 And 120 Km And Some Of Its Characteristics, J. F. Stampfer, J. A. Anderson

Chemistry Faculty Research & Creative Works

The feasibility of locating the urban plume of a moderately large urban area, as far as 120 km downwind, is shown. The method utilizes a single engine aircraft and aerosol instrumentation. A summary of the data obtained from 34 flights, during an 8-month period, is presented and the problems involved in interpreting the data are discussed. These difficulties include nonuniform background levels outside the plume, changing relative humidity, low wind speeds and stable atmospheric layers. The plume was characterized by concentrations of small particles (0.15 < r < 0.3 μm) ca. 1.5 times that in background air and concentrations of large particles (0.3 < r < 1.3 μm) usually greater than twice that in the background. The ratio of the concentrations of small particles to large particles in the plume was about one-half of that in the background. © 1975.

Classification Of Surficial Materials, James Hadley Williams

Doctoral Dissertations

"A surficial materials classification system has been designed to fit the needs of a geologist in mapping and classifying surficial materials. The system developed in this study is intended primarily for analysis of surficial materials where time-stratigraphic markers are not applicable or recognized. Primary classification is based on fabric and mode of origin supplemented by data on engineering and pedologic properties.

Several types of classification systems presently exist for use in soil investigations. Only three of these systems have found widespread acceptance, two serving the engineering profession and the other the needs of the soil scientist. These systems are not …

Erratum: Multimedia Dispersion Relation For Surface Electromagnetic Waves. (The Journal Of Chemical Physics (1975) 62 (1674)), C. A. Ward, K. Bhasin, Robert John Bell, Ralph William Alexander, I. Tyler

Physics Faculty Research & Creative Works

No abstract provided.

Biquadratic Exchange And First-Order Ferromagnetic Phase Transitions, Harry A. Brown

Physics Faculty Research & Creative Works

We have calculated some properties of a ferromagnet using a Heisenberg Hamiltonian with a biquadratic exchange term added. The constant-coupling approximation was employed. If the strength of the biquadratic exchange relative to the bilinear is given by a dimensionless parameter α, there is a critical value αc at which the phase transition changes character from second order for αα>αc. The spontaneous magnetization, the exchange energy, and the spin-correlation function show discontinuous jumps at α=αc and unstable behavior for α>αc. © 1975 The American Physical Society.

Use Of The Psi Technique In Prerequisite Courses, John T. Park, William R. Snow

Physics Faculty Research & Creative Works

An engineering physics course, in which the Personalized System of Instruction (PSI) technique has been used, has been designed to meet the requirements that all of a prescribed list of subjects be covered and that the course be completed within a single semester. The course was modified so that it has two levels of mastery for each unit: a passing level and a complete mastery level. All students were required to reach a passing level of mastery on all of the required material. Grades were assigned according to the number of complete mastery level examinations passed. It was found that …

Heavy Metal Contamination In Soil Around A Lead Smelter In Southeast Missouri, David Lewis Butherus

Masters Theses

"In order to determine the extent of possible heavy metal contamination, more than 963 samples of leaf litter and soil were collected from 410 sample stations around the AMAX smelter in southeast Missouri. Dried samples of leaf litter and minus 80 mesh soil fractions were analyzed for cadmium, copper, lead, and zinc by atomic absorption spectrophotometry. Minus 80 mesh soil fractions were also analyzed for sulfur using x-ray fluorescence methods. Ranges of heavy metal concentrations in leaf litter were: cadmium, 0.13 μg/g to 175 μg/g; copper, 4.2 μg/g to 6500 μg/g; lead, 50 μg/g to 130,000 μg/g; and zinc, 26 …

The Use Of Surface Electromagnetic Waves To Measure Materials Properties, Ralph William Alexander, Robert John Bell

Physics Faculty Research & Creative Works

An Elementary Introduction to Surface Electromagnetic Waves (SEW) is Presented. the Emphasis is on Those Features of SEW Which Make Them Useful for Measuring Optical Properties of Thin Layers on Metals. the So-Called Two-Prism Technique for Making Such Measurements is Discussed, Some Preliminary Experimental Results Are Given, and Some Possible Applications Are Presented. © 1975.

Excitation Of Atomic Hydrogen To The N=2 States By 15-200-Kev Protons, John T. Park, J. E. Aldag, J. M. George

Physics Faculty Research & Creative Works

Cross sections for the process H+ + H H+ + H* (n=2) are determined from the energy-loss spectra of 15-200-keV protons. After normalization at 200 keV to the Born approximation, the maximum value (1.07 x 10-16 cm2 at 60 keV) lies below close-coupling calculations and above Glauber-approximation calculations. The agreement with low-energy (5-30-keV) data of others is very good. © 1975 The American Physical Society.

A High-Power Pulsed Xenon Ion Laser As A Pump Source For A Tunable Dye Laser, Laird D. Schearer

Physics Faculty Research & Creative Works

An inexpensive pulsed xenon ion laser with peak power outputs up to 4 kW has been constructed and used as a pump source for a tunable rhodamine 6G dye laser with a 0.25-A bandpass in the yellow-red range of the spectrum. The dye laser is tunable from 5465 to 6300 A. Over 50 W are obtained at the peak of the tuning range. Copyright © 1975 by The Institute of Electrical and Electronics Engineers, Inc.

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. …

A Study Of Some Life Testing Distributions, Robert Marvin Smith

Doctoral Dissertations

"This dissertation is presented in publication form and consists of three articles. The first article considers a new life-testing distribution which has the property of possessing a failure rate function which can be U-shaped or exponentially increasing depending on the value of the shape parameter. In addition, this article considers generalized least squares type estimators for location-scale distributions, then uses these estimators in the analysis of the exponential-power distribution. Tables are provided for which inferences on the location and scale parameters and on the reliability can be obtained. The second article gives relationships between a goodness-of-fit statistic based on a …

A Heuristic Algorithm For The Multi-Terminal Vehicle Dispatch Problem Using The Modified Sweep Algorithm, Jerry George Johnson

Doctoral Dissertations

"A heuristic algorithm is developed for solving the multi-terminal vehicle dispatch problem. The demand points are first assigned to terminals using a scheme that minimizes the cost of each assignment. Single-terminal vehicle dispatch problems are then solved at each terminal using a heuristic procedure, called the Sweep Algorithm. A sequence of trial reassignments are then attempted in order to obtain further improvements in the overall solution. Eleven multi-terminal vehicle dispatch problems are presented and their solutions, derived by this procedure, are given.

Several changes are also proposed for the Sweep Algorithm in order to improve the solutions obtained and to …

System Reliability: Exact Bayesian Intervals Compared With Fiducial Intervals, Kathryn P. Berkbigler, James K. Byers

Computer Science Faculty Research & Creative Works

This paper compares numerically two different, widely used lower limit estimates for the reliability of a series system: Bayesian limits and fiducial limits. The fiducial limits are obtained by Monte Carlo simulation because of its simplicity and ease of computer programming. Subsystem failures are s-independent and exponentially distributed; life test data are available for estimating the failure rate of each system. Copyright © 1975 by The Institute of Electrical and Electronics Engineers, Inc.

Applications Of Metrics Over Tikonov Semifields And Fixed Points In Hilbert Spaces, John David Kubicek

Doctoral Dissertations

"For Non expansive mappings on locally convex spaces, sufficient conditions are given for the set of fixed points to be a Non expansive retract. Also, sufficient conditions are given for certain semigroups of asymptotically Non expansive mappings to have a common fixed point.

Several results concerning convergence of the sequence of iterates in metric spaces are generalized to Hausdorff uniform spaces.

In Hilbert spaces, sufficient conditions are given for convergence of a Mann iteration process of strictly quasi pseudo contractive mappings. An example is given to show the process does not, in general, converge for pseudo contractive mappings"-- Abstract, p. …

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, …

Using Ibm's Information Management System To Implement A Relational Data Base, Melvin Arthur Rushton

Masters Theses

"A relational model of data has been the topic of several papers which deal with the question of the underlying design philosophy of data base systems. E. F. Codd, C. J. Date, and others have discussed the application of relation theory to formatted data, the objectives of such an approach, normalization of relations, and languages for manipulating the model (data sublanguages). Few papers have delt with storage constructs or access techniques for a relational data base. Indeed, it was not necessary that they do so, for the user of such a system is only concerned with the information available in …

Toacs : An Interactive Computer Graphic Display Model Of A Theaterwide On-Line Air Combat Simulation, Herman William Blick

Masters Theses

"On-line interactive graphics is a very effective research tool for examining the concepts, components and design parameters of theater warfare involving multiple aircraft. The aim of the present research is to design an on-line computer system which utilizes interactive graphic displays to develop a dynamic, two-sided mathematical model of theaterwide tactical fighter combat operations. The model, called TOACS, is very useful in simulating and evaluating airborne defense systems and the problems common to this type of simulation — such as the formulation of battle strategy for the commitment and guidance of interceptors against threat aircraft -- as well as those …

Geochemical And Biogeochemical Studies In The Hansonburg Mining District, New Mexico, Alan Nathan Silverman

Masters Theses

"The Hansonburg mining district is in Socorro county in south central New Mexico. A Paleozoic section of thick Pennsylvanian limestone units, thin shale and arkose layers and thick Permian units of sandstone, siltstone and gypsiferous beds interlayered with thin limestone units unconformably overlie a Precambrian basement of granite. The sedimentary rocks are folded with north trends and plunges. Northerly, some easterly and northwesterly trending faults cut the folds. Galena, fluorite, and barite mineralization occurs along some of the northerly faults and as bedded replacements and fissure fillings in the Pennsylvanian Council Spring limestone.

Geological mapping and geochemical soil surveys of …

Fluid Inclusion Geothermometry Of Tri-State Sphalerite, Chi-Sheng Wei

Masters Theses

"Fluid inclusions in successively deposited generations of sphalerite from the Tri-State district have been examined for geothermometry as a function of time. The main stage of vug-filling sphalerite has been studied most intensively and as many as 83 fluid inclusions have been examined in a single crystal. These sphalerite crystals are commonly zoned, and their filling temperatures exhibit a general pattern of declining temperature from their cores outward, from about 135°C down to 90°C. The decline is not a steady one, but rather it is characterized by fluctuations commonly about 15-20°C. Some fluctuations have magnitudes as great as 50-60°C, with …

Molecular Model For Ice Clusters In A Supersaturated Vapor, Barbara N. Hale, P. L. M. Plummer

Physics Faculty Research & Creative Works

A molecular model previously applied to prenucleation water clusters is used to examine ice I_h, embryos. The canonical partition function is evaluated for clusters having from 6 to 64 water molecules. The intermolecular vibrational free energies are extrapolated to clusters containing up to 120 molecules and free energies of formation, nucleation rates, and critical supersaturation ratios are calculated and compared with experiment. For the clusters studied, the ice I_h structure appears to be much less stable at all temperatures than the more spherical clathratelike cluster.

Restrictions On The Potential And Cross Section For Collisions Between Rigid Rotors, Louis Biolsi Jr.

Chemistry Faculty Research & Creative Works

A restricted distorted-wave treatment of the total cross section when two rigid diatomic molecules with orbital and nuclear spin angular momenta collide is examined. There are certain restrictions on the intermolecular potential and on the possible combinations of the various quantum numbers. These restictions are examined for the lowest order nonspherical elastic and the lowest order inelastic contributions to the total cross section. The effects of degeneracy averaging and of collisions between indistinguishable molecules are also briefly examined.