Physical Sciences and Mathematics Commons^™

Calculation Of Electron Capture Cross Sections Of Collisions Of Be ²⁺ On H, A. E. Wetmore, H. R. Cole, Ronald E. Olson

Physics Faculty Research & Creative Works

Using the perturbed stationary state method, including electron translation factors, the authors have calculated electron capture cross sections for the helium-like ions Be²⁺ and B³⁺ incident on ground-state atomic hydrogen. The molecular structure calculation employs pseudo-potentials to represent the inactive K-shell electrons on the incident ions. The calculated cross sections vary rapidly in the 107 cm s-1 velocity range (E approximately 1 keV amu-1). The calculations show preferential transfer to the Be⁺(2s) and the B²⁺(2p) product states. The calculations for B³⁺+H are in good agreement with experimental measurements of Cradall et al …

Double Electron Transitions In Collisions Between Multiply Charged Ions And Helium Atoms, Ronald E. Olson, A. E. Wetmore, M. L. Mckenzie

Physics Faculty Research & Creative Works

A semiclassical model for He is applied to the study of multiply charged ions colliding with He at intermediate energies. Single and double-electron capture and ionisation and capture-ionisation reactions are studied for incident-ion charge states q=+1 to +50 at 1 MeV amu-1. For charge states q>or approximately=+10, single electron capture is found to be dominated by a two-electron transition in which one electron is captured and the other is ionised.

Negative Ion Drift Velocities In Mixtures Of Methane And Sulphur Hexafluoride, M. C. Cornell, Ian M. Littlewood

Physics Faculty Research & Creative Works

The velocities of negative ions drifting in mixtures of methane and Sulphur hexafluoride have been measured. Measurements were made as a function of gas composition, reduced electric field strength between 3 and 185 Td, and total gas pressure in the range 100-600 Torr at 300K. The data indicate that SF 6- (SF6) ions are the dominant ion in all of the gas mixtures studied. Extrapolation of the data using Blanc's Law was used to determine the velocity of Sulphur hexafluoride ions drifting in pure methane.

Photoconductivity Parameters In Lithium Niobate, Robert Gerson, J. F. Kirchhoff, L. E. Halliburton, D. A. Bryan

Physics Faculty Research & Creative Works

Measurements on a variety of doped (magnesium and/or iron) and undoped lithium niobate crystals in the oxidized state demonstrate an Arrhenius dependence of dark conductivity on reciprocal temperature between 460 and 590 K. All of the crystals had roughly the same conductivity and activation energy (1.21 eV) over the temperature range, implying that all have about the same free-carrier concentration and mobility. The enhanced photoconductivity of magnesium-doped lithium niobate is attributed to a greatly reduced trapping cross section of Fe³⁺ for electrons, the smaller cross section being due to a changed substitutional site for Fe³⁺. The Fe …

Experimental Test Of Higher-Order Electron-Capture Processes In Collisions Of Fast Protons With Atomic Hydrogen, Hans G. Vogt, Reinhold S. Schuch, Edson L B Justiniano, Michael Schulz, W. Schwab

Physics Faculty Research & Creative Works

We present measurements of the angular distribution of fast hydrogen atoms formed by electron capture of 2.8- and 5.0-MeV protons in atomic hydrogen. In the angular region of the Thomas peak (0.47 mrad) the experimental results obtained with this pure three-body collision system are in reasonable agreement with a strong-potential Born calculation and the impulse approximation, but not with other higher-order theories.

Two-Step Stabilization Of Autoionizing States, J. Greg Story, Linn D. Van Woerkom, William E. Cooke

Physics Faculty Research & Creative Works

A two-step process using internal conversion and fluorescence to stabilize the 6P_3/211d autoionizing state of barium has been observed. The internal conversion produces very highly excited autoionizing Rydberg states, which then emit fluorescence to produce singly excited, bound states. Inclusion of this process should bring calculations closer to agreement with recent measurements of dielectronic recombination.

Theoretical Calculation Of The Transport Properties Of Monatomic Lithium Vapor, Paul M. Holland, Louis Biolsi Jr., James C. Rainwater

Chemistry Faculty Research & Creative Works

Transport properties of dilute monatomic gases depend on two body atom-atom interaction potentials. When two ground state (²S) lithium atoms interact, they can follow either of two potential energy curves corresponding to the Li₂ molecule in the X¹Σ⁺_g or ³Σ⁺_u state. Transport collision integrals for these states have been calculated by accurately representing quantum mechanical potential energy curves with the Hulburt-Hirschfelder potential. The excellent agreement of calculated viscosities with experimental results provides further evidence that this potential can be used to estimate accurately transport properties under conditions where experimental data …

Measurement Of The Lifetime Of The Metastable 5d3/226d3/2, J=0 Autoionizing State Of Barium, Linn D. Van Woerkom, J. Greg Story, William E. Cooke

Physics Faculty Research & Creative Works

We report a measurement of the lifetime of the metastable 5d_3/226d_3/2, J=0 autoionizing state of barium. We have determined the lifetime to be 190(10) ns.

Weihnacht And Its Variants As Personal And Place Names, David S. Wulfman

Chemistry Faculty Research & Creative Works

No abstract provided.

Mica: Prototyping An Expert System Consultant, Joseph Howard Marchal, Arlan R. Dekock

Computer Science Technical Reports

The United States, as the world's largest producer and consumer of scrap and flake mica, has an obvious economic interest in applications of artificial intelligence technology that would expedite beneficiation of mica. In the fall of 1985, personnel of the Tuscaloosa and Rolla research centers of the Bureau of Mines and of the University of Missouri-Rolla, Institute for Artificial Intelligence started the following long term research project: Develop an Expert System Consultant for the three basic stages of mica beneficiation: Stage 1: characterization of the material; Stage 2: treatment to obtain a concentrate; and Stage 3: evaluation of the resulting …

Genesis Of An Expert System For Umr Degree Auditing, Ruth Sue Dare, Arlan R. Dekock

Computer Science Technical Reports

This paper describes the features, design, and development of an expert system for degree auditing at the University of Missouri--Rolla. It summarizes artificial intelligence as it is known today while specifically addressing expert systems. It describes selected expert systems currently in existence.

The present audit procedure utilized at the University of Missouri--Rolla is discussed. A description is given of the design and development of an expert system, written in LISP, to conduct a degree audit. Finally there are concluding remarks which include an analysis of the system and a discussion of possible system enhancement.

A Computerized Audio-Visual Speech Model, Joaquin Alberto Vila Ruiz, Arlan R. Dekock

Computer Science Technical Reports

This thesis describes an expert system able to animate (graphically) and reproduce (acoustically) a text in any language which uses the Latin alphabet. A rule editor has been developed to create and modify the set of letter-to-sound rules of the target language. A parser has been implemented to apply the set of rules and translate text-to-speech. Each phoneme has a unique sound and thus requires its particular positioning of the vocal organs which are displayed in two different projections: a front view and a profile cross view of a human face in synchronization with the output sounds of the speech …

Application Of A Scaled Homogeneous Nucleation-Rate Formalism To Experimental Data At T≪TC, Barbara N. Hale

Physics Faculty Research & Creative Works

It is pointed out that for temperatures T<0.5T_c, where T_c is the critical temperature, the classical steady-state nucleation-rate formalism of Becker and Doring predicts an approximate critical supersaturation ratio S_cr (for the onset of nucleation) given by lnS_cr/Ω^3/2~0.53(T_c/T-1)^3/2. Ω is a material-dependent quantity approximately equal to the excess surface entropy per molecule. For most substances Ω ~ 2.0 and for associated liquids Ω ~ 1.5.The experimental data (for nucleation from vapor to liquid) from diffusion chamber and nozzle beam studies are found to be consistent with the above …

Data Structure For The Use Of Patterns In The Perceptual Ordering Of The Game Of Chess, Russ L. Hanna, Arlan R. Dekock

Computer Science Technical Reports

It is well known that the way one perceives a problem can influence the difficulty of solving the problem in a profound way. In the case of computer chess playing programs, one finds that most programs perceive the game in much the same way. They are all based on Shannon's original proposal for chess playing programs. His approach was to generate all of the possible combinations of moves up to a certain number of plays and then a subset of all combinations to a deeper level thereafter. Each of these moves would then be evaluated as to its relative worth. …

A Semantic Basis For Parallel Algorithm Design, Roger E. Eggen, John R. Metzner

Computer Science Technical Reports

As computing demands increase, emphasis is being placed on parallel architectures- To efficiently use parallel machines, software must be designed to take advantage of these machines. This research concentrates on an abstraction of algorithm design to permit the expression of parallel programs. The abstraction emphasizes thought about algorithms at a high level as opposed to algorithm implementation at a statement level. A model based on data flow allows algorithm expression using flow diagrams. The model specifies operating system requirements that support parallel programming at a module level. Paths are used to carry data between modules. Data enter modules through ports. …

Lexical Analysis Using Table Look-Up, Brian Keith Smith, Dominic Soda, George Winston Zobrist

Engineering Management and Systems Engineering Faculty Research & Creative Works

No abstract provided.

Energy Transfer Collisions Between Vibrationally Excited Molecular Nitrogen And Atoms, Laird D. Schearer

Physics Faculty Research & Creative Works

Chemiluminescent reactions between metastable states of molecular nitrogen and atoms are used to determine the vibrational temperatures of these Non radiating molecular systems. The excitation rates of Na, Mg, Cd, and Zn are used to obtain the vibrational temperature of N2(X 1Σ) and N2(A 3Σ) states in a fast-flowing nitrogen afterglow. The exponential dependence of the intensities of the emission from atoms excited by the energy transfer collisions on the energy of the level yields vibrational temperatures on the order of 3100 K. We also report the presence of apparent strong selection rules on the total spin of the system …

On Weighted Integrability Of Trigonometric Series And L¹-Convergence Of Fourier Series, William O. Bray, Caslav V. Stanojević

Mathematics and Statistics Faculty Research & Creative Works

Result concerning integrability of f(x)L(l/x)(g(x)L(l/x)), where f(x)(g(x)) is the pointwise limit of certain cosine (sine) series and L(•) is slowly vary in the sense of Karamata [5] is proved. Our result is an excludedďcase in more classical results (see [4]) and also generalizes a result of G. A. Fomin [1]. Also a result of Fomin and Telyakovskii [6] concerning L1-convergence of Fourier series is generalized. Both theorems make use of a generalized notion of quasi-monotone sequences. © 1986 American Mathematical Society.

Lna: A New Cw Nd Laser Tunable Around 1.05 And 1.08 Μm, Laird D. Schearer, Michele Leduc, Daniel Vivien, Anne Marie Lejus, Jeanine Thery

Physics Faculty Research & Creative Works

We have investigated the CW laser properties of the lanthamide hexa-aluminate La0.9Nd0.1MgAl11O19 at room temperature. When a I cm long crystal is pumped by an Ar⁺ laser (514 nm) or a Kr⁺ laser (752 nm), CW emission is obtained with slope efficiencies of 10 and 26 percent, respectively. A four-plate Lyot filter in the cavity forces the LNA crystal to oscillate in either of the two major bands centered at 10 820 A (tuning range 80 A) and 10 545 A (tuning range 35 Å). Copyright © 1986 by The Institute of Electrical and Electronics Engineers, Inc.

Banach Spaces Of Functions Analytic In A Polydisc, Leon M. Hall

Mathematics and Statistics Faculty Research & Creative Works

This paper is concerned with functions of several complex variables analytic in the unit polydisc. Certain Banach spaces to which these functions might belong are defined and some relationships between them are developed. The space of linear functionals for the Banach space of functions analytic in the open unit polydisc and continuous on the unit torus is then described in terms of analytic functions using an extension of the Hadamard product.

Comments On The Raindrop Problem, I. Adawi

Physics Faculty Research & Creative Works

No abstract provided.

Race, Sex And Occlusive Cerebrovascular Disease: A Review, L. R. Caplan, P. B. Gorelick, D. B. Hier

Chemistry Faculty Research & Creative Works

No abstract provided.

Plasma‐Substrate Interaction: Effect Of Volatile Oligomers In Silicone Rubber On Plasma Polymerization Of Fluorine‐Containing Monomers, Y. ‐S Yeh, H. Yasuda

Chemistry Faculty Research & Creative Works

The cause of the conspicuous Si content consistently observed on plasma polymers deposited on silicone rubber was investigated in this study. Plasma polymers of tetrafluoroethylene and of hexafluoroethane were deposited on the inside surface of Silastic tubings with and without oligomers by using a semicontinuous plasma polymerization reactor. This tube coating reactor is unique in the sense that the only surface which interacts with the plasma is the substrate surface (i.e., inside wall of tubing) and that plasma polymerization occurs in a very small volume of 3.3‐mm‐I.D. and 2‐cm‐long section of tubing at any given time. These two factors render …

A Non-Aqueous Lamellar Liquid Crystal With An Ionic Surfactant-Long Chain Alcohol Combination, Stig Friberg, Paul Liang, Yuh Chirn Liang, Bettye Greene, Ron Van Gilder

Chemistry Faculty Research & Creative Works

A non-aqueous lamellar liquid crystal of sodium dodecyl sulfate, decanol and glycerol was prepared and compared with its aqueous counterpart. The results show that the stability of the liquid crystal with glycerol is critically dependent on the surfactant/alcohol ratio, whereas the liquid cry. The interlayer spacing was smaller for the glycerol system than for the water system at finite amount of solvent, but the value extrapolated to zero so. © 1986.

Solvation Changes Induced In A Lyotropic Lamellar Liquid Crystal Containing Solubilized Benzene, Anthony J.I. Ward, Shankar B. Rananavare, Stig Friberg

Chemistry Faculty Research & Creative Works

Deuterium NMR quadrupole splitting's of deuterated benzene and water were studied as a function of their composition in the aqueous lamellar phase of Penta ethylene glycol n-dodecyl ether. An interpretation of the results is given in terms of hydration changes of the poly(oxyethylene) chains related to changes in the benzene solvation and location within the head-group region. © 1986, American Chemical Society. All rights reserved.

The Mechanism Of Hydrotrope Action Of A Dicarboxylic Acid, Stig Friberg, S. B. Rananavare, D. W. Osborne

Chemistry Faculty Research & Creative Works

The mechanism of the hydro trope action of a dicarboxylic acid Mono soap was investigated by determination of the change in order parameter of the amphiphile in a lamellar liquid crystal. The results showed addition of the hydro trope considerably to reduce the order while addition of a surfactant had no effect. © 1986.

On The Mean Time Between Failures For Repairable Systems, Max Engelhardt, Lee J. Bain

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Much of the recent work on modeling repairable systems involves Poisson processes with nonconstant intensity functions, viz, nonhomogeneous Poisson processes. Since times between failures are not identically distributed when the process is nonhomogeneous, it is not clear what concept should take the place of the mean time between failures in assessing the reliability of a repairable system. A number of alternate concepts can be found in the literature. We investigate the relationship between two of the most frequently considered alternatives: the reciprocal of the intensity function, and the mean waiting time from t until the next failure. Theorem 1 states …

Surfactant Association Structures And The Stability Of Emulsions And Foams, Stig Friberg, Concepcion Solans

Chemistry Faculty Research & Creative Works

Traditional surfactants in combination with water and a more hydrophobic amphiphile, such as an alcohol or a carboxylic acid, present a rich variety of colloidal association structures, both micelles and lyotropic liquid crystals. The presence of such association structures has a pronounced influence on the stability of macro dispersed systems such as emulsions and foams. A few examples of such an influence are discussed. © 1986, American Chemical Society. All rights reserved.

A Semantic Basis For Parallel Algorithm Design, Roger E. Eggen

Doctoral Dissertations

"As computing demands increase, emphasis is being placed on parallel architectures- To efficiently use parallel machines, software must be designed to take advantage of these machines. This research concentrates on an abstraction of algorithm design to permit the expression of parallel programs. The abstraction emphasizes thought about algorithms at a high level as opposed to algorithm implementation at a statement level. A model based on data flow allows algorithm expression using flow diagrams. The model specifies operating system requirements that support parallel programming at a module level. Paths are used to carry data between modules. Data enter modules through ports. …

Specification And Efficiency Evaluation Of A Data Communications Protocol, Patricia Ann Anderson

Masters Theses

"A data communications protocol for an established operating environment is formally specified. Motivation for the development of this protocol is presented, with consideration for the future communications requirements of the system.

Factors influencing the performance of a protocol are reviewed. Error recovery, network addressing, flow control, traffic prioritization, and initialization and termination sequences are examined in general and with respect to the protocol development.

In conclusion, a mathematical evaluation of the efficiency of the protocol is provided, using Tanenbaum's equations for determining channel utilization. The theoretical channel utilization of a perfect system, without propagation delay or error, is compared with …