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Articles 4921 - 4950 of 6056

Full-Text Articles in Physical Sciences and Mathematics

Extensions, Generalizations, Characterizations And Testing For Independence Through Infinite Divisibility, Edward Joul Danial Jan 1982

Extensions, Generalizations, Characterizations And Testing For Independence Through Infinite Divisibility, Edward Joul Danial

Doctoral Dissertations

This dissertation investigates various related topics around the exciting concept: "Infinite Divisibility." First, two intricate distributions, namely, the univariate generalized Waring and the hyper-Poisson are proved to be infinitely and noninfinitely divisible, respectively. Analysis and computer approaches are employed. This itself extends the use of some results introduced by Katti, Steutel and Warde. Secondly, generalizations to Warde, Katti and Steutel's sufficient conditions and related results are achieved. Then, numerical application is presented. Thirdly, characterizations through infinite and finite divisibility are obtained. The Poisson, negative binomial, geometric, Bernoulli and uniform c haracterizations in terms of infinite divisibility are deduced. Some of …


Mineralogical, Textural, And Paragenetic Studies Of Selected Ore Deposits Of The Southeast Missouri Lead-Zinc-Copper District And Their Genetic Implications, Kenneth Bruce Horrall Jan 1982

Mineralogical, Textural, And Paragenetic Studies Of Selected Ore Deposits Of The Southeast Missouri Lead-Zinc-Copper District And Their Genetic Implications, Kenneth Bruce Horrall

Doctoral Dissertations

“A detailed paragenetic study of Pb-Zn-Cu ores from the Viburnum Number 28, Brushy Creek, and Goose Creek mines in the Southeast Missouri lead district indicates a complicated paragenesis characterized by repeated periods of mineral deposition. The sequence is composed of nineteen minerals including abundant galena, sphalerite, chalcopyrite, pyrite, marcasite, dolomite, calcite, and quartz and minor siegenite, bornite, bravoite, blaubleibender covellite, covellite, gersdorffite, digenite, enargite, tennantite, dickite, and malachite.

The paragenesis indicates that the ore solutions evolved in the following order: (1) Cu-rich, (2) Co-Ni-rich, (3) Pb-Zn-rich, and (4) Fe-rich. Subsequent repeated generations include cubic galena, later sphalerite, and minor crystalline …


A Study Of The Critical Cluster Size For Water Monolayer Clusters On A Model Agi Basal Substrate, Richard C. Ward, Barbara N. Hale, Sergio Terrazas Jan 1982

A Study Of The Critical Cluster Size For Water Monolayer Clusters On A Model Agi Basal Substrate, Richard C. Ward, Barbara N. Hale, Sergio Terrazas

Physics Faculty Research & Creative Works

We present a formalism and estimate a critical cluster size for water monolayer formation on a (rigid) model AgI basal substrate. The formalism is modified from that developed for vapor clusters [B. N. Hale and R. C. Ward, J. Stat. Phys. 28, 487 (1982)] and uses a Metropolis Monte Carlo method developed by Squire and Hoover [J. Chem. Phys. 50, 701 (1969)] to determine (Helmholtz) free energy differences for clusters containing n and n-1 molecules. Calculations for clusters of n=1, 2, 3, 4, 6, and 24 water molecules on a model AgI basal face at 265 K are …


D- Production By Charge Transfer Of (0.3 - 3)-Kev D+ In Thick Alkaline-Earth Vapor Targets: Interaction Energies For Cah+, Cah, And Cah-, R. (Robert) H. Mcfarland, A. S. Schlachter, J. W. Stearns, B. Liu, R. (Ronald) E. Olson Jan 1982

D- Production By Charge Transfer Of (0.3 - 3)-Kev D+ In Thick Alkaline-Earth Vapor Targets: Interaction Energies For Cah+, Cah, And Cah-, R. (Robert) H. Mcfarland, A. S. Schlachter, J. W. Stearns, B. Liu, R. (Ronald) E. Olson

Physics Faculty Research & Creative Works

Equilibrium charge-state fractions of energetic deuterium ions and atoms emerging from alkaline-earth (magnesium, calcium, strontium, and barium) vapor targets are reported in the range of 0.3- to 3-keV incident D+ energy. Deuterium negative-ion production in thick barium and calcium vapor targets equals similar production in cesium vapor (34%). Moreover, the maximum D- production in strontium vapor exceeds that for all other known gas or vapor targets and reaches 50% at 500 eV. Theory does not quantitatively describe these results, although ab initio molecular-interaction-energy calculations on the neutral and negative-ion CaH systems lead to the prediction of large D- yields at …


Determination Of The Absolute Structure Factor For The Forbidden (222) Reflection In Silicon Using 0.12-Γ Rays, R. W. Alkire, W. (William) B. Yelon, J. R. Schneider Jan 1982

Determination Of The Absolute Structure Factor For The Forbidden (222) Reflection In Silicon Using 0.12-Γ Rays, R. W. Alkire, W. (William) B. Yelon, J. R. Schneider

Physics Faculty Research & Creative Works

A room-temperature determination of the absolute structure factor for the forbidden (222) reflection in silicon has been conducted at the University of Missouri Research Reactor with 103-keV gamma rays. The measured structure factor of F(222)=1.456 is in excellent agreement with five of the earlier intensity measurements and is significantly different from any value determined using Pendellösung techniques. An increase in accuracy over previous intensity measurements by a factor of between 2 and 10 has been achieved and is made possible through the use of monoenergetic, short-wavelength gamma rays, which allow absolute measurements to be made in Laue geometry on relatively …


A Study Of Poly(P‐Xylylene)‐Coated Asf5‐Doped Polyacetylene, J. E. Osterholm, H. Yasuda, L. L. Levenson Jan 1982

A Study Of Poly(P‐Xylylene)‐Coated Asf5‐Doped Polyacetylene, J. E. Osterholm, H. Yasuda, L. L. Levenson

Physics Faculty Research & Creative Works

Electrical conductivity measurements and scanning electron microscopy have been used to study uncoated and poly(p‐xylylene)‐coated samples of polyacetylene doped with AsF5. These initial results indicate a considerable reduction in the decay rate of conductivity in the presence of oxygen as well as a decreased rate of thermal decomposition of the dopant when heated between 50°C and 115°C in vacuum by the coating. Copyright © 1982 John Wiley & Sons, Inc.


Production Of Highly Charged Rare-Gas Recoil Ions By 1.4-Mev/Amu U44+, A. S. Schlachter, W. Groh, A. Müller, H. F. Beyer, R. Mann, Ronald E. Olson Jan 1982

Production Of Highly Charged Rare-Gas Recoil Ions By 1.4-Mev/Amu U44+, A. S. Schlachter, W. Groh, A. Müller, H. F. Beyer, R. Mann, Ronald E. Olson

Physics Faculty Research & Creative Works

Recoil-ion-production cross sections in rare gases are measured for 1.4-MeV/amu U44+ ions and are calculated for 1-5-MeV/amu projectiles in charge state 44 + with the use of the classical-trajectory Monte Carlo method and the independent-electron model. The calculations reasonably predict the net-charge-production cross sections, which exceed 10-13 cm2 for the heavy rare gases; the calculations are found to underestimate the cross sections for low-charge-state recoil ions and to overestimate the cross sections for high-charge-state recoil ions. The experimental cross sections for production of highly charged recoil ions are found to be large, e.g., greater than 1x10-16 cm2 for production of …


On The Curie Temperatures Of Amorphous Ferromagnets, Harry A. Brown Jan 1982

On The Curie Temperatures Of Amorphous Ferromagnets, Harry A. Brown

Physics Faculty Research & Creative Works

No abstract provided.


Electron Density Measurements In A Laser Induced Na Plasma, D. J. Krebs, Laird D. Schearer Jan 1982

Electron Density Measurements In A Laser Induced Na Plasma, D. J. Krebs, Laird D. Schearer

Physics Faculty Research & Creative Works

The optical emission spectrum of a recombining Na plasma is observed. The shift and broadening of the spectral line emission due to electron collisions is observed. Electron densities on the order of 5x1014 cm -3 are calculated from the shift measurements. The results agree well with electron densities obtained in the same system from Saha plots of excited state densities. © 1982 American Institute of Physics.


Homogeneous Nucleation Of Ethanol, John L. Schmitt, G. W. Adams, R. A. Zalabsky Jan 1982

Homogeneous Nucleation Of Ethanol, John L. Schmitt, G. W. Adams, R. A. Zalabsky

Physics Faculty Research & Creative Works

The authors have used an expansion cloud chamber to measure homogeneous nucleation rate as a function of temperature and supersaturation in ethanol. Nucleation rates from 102 to 105 drops/cm3 sec were measured in the temperature range 252-272 °K. An empirical functional fit to the data is used to extrapolate for comparison with other data in the literature at a nucleation rate of 1 drop/cm3 sec and to compare with the predictions of the classical Becker-Doring homogeneous nucleation theory. A full listing of the data and thermodynamics constants used in the reduction of the data is given in an appendix. © …


Measurement Of The Wear Properties Of Metallic Solids With A Falex Lubricant Testing Machine, Edward Boyd Hale, Chun-Ping John Meng, Ronald A. Kohser Jan 1982

Measurement Of The Wear Properties Of Metallic Solids With A Falex Lubricant Testing Machine, Edward Boyd Hale, Chun-Ping John Meng, Ronald A. Kohser

Physics Faculty Research & Creative Works

A modified Falex Lubricant Testing Machine has been used to determine wear properties of metallic solids. In particular, wear mass loss, wear volume loss, wear rates, and other parameters have been determined for a basic steel, as heat treated and after ion implantation. Wear rate improvements of more than an order of magnitude were found in a nickel-chrome steel (SAE 3135) implanted with 2.5x1017 N+2/cm2. Wear tests were conducted with a cylinder-in-groove geometry in a mild lubricating oil with loads greater than 540 N, which corresponded to pressures which exceeded 108N/m2 …


Sequential Probability Ratio Tests For The Shape Parameter Of A Nonhomogeneous Poisson Process, Lee J. Bain, Max Engelhardt Jan 1982

Sequential Probability Ratio Tests For The Shape Parameter Of A Nonhomogeneous Poisson Process, Lee J. Bain, Max Engelhardt

Mathematics and Statistics Faculty Research & Creative Works

Sequential probability ratio tests for the shape parameter of one or more nonhomogeneous Poisson processes, with power intensity functions, are provided. The tests can be performed when the scale parameter is an unknown nuisance parameter; the effective loss of not knowing the scale parameter is one observation per process. The resulting tests can be expressed in terms of the maximum likelihood estimators of the shape parameters for the usual fixed sample procedure. A further advantage of the present approach is that the scale parameters for different processes, in the multiple sample procedures, need not be equal. Approximations for the operating …


Hot-Wire Anemometer Behaviour In Low Velocity Air Flow, P. J. Christman, Josef Podzimek Dec 1981

Hot-Wire Anemometer Behaviour In Low Velocity Air Flow, P. J. Christman, Josef Podzimek

Physics Faculty Research & Creative Works

The behavior characteristics of a commercially available hot-wire anemometer have been examined in the presence of low velocities, lwss than 0.1 m/s for the most part, and in both horizontal and vertical air flows. The orientation of the probe in a horizontal flow has been found to have a definite effect on velocity measurements, and a lower limit to the reliable application of hot-wire anemometry has been evaluated for a particular type of probe. Vertical flow measurements have resulted in the discovery of the magnitude of natural convective velocity, and a possible method for determining the dimensions of the temperature …


Precision Expansion Cloud Chamber For Homogeneous Nucleation Studies, John L. Schmitt Dec 1981

Precision Expansion Cloud Chamber For Homogeneous Nucleation Studies, John L. Schmitt

Physics Faculty Research & Creative Works

The author describes an expansion cloud chamber for the study of the nucleation of a single component vapor (homogeneous nucleation). The design draws on the many years of experience in this Center in construction of chambers for homogeneous nucleation of water. Design features of the chamber are exact control of temperature (±0.03° C), pressure (±0.5 mm Hg), and automatic control of cycling. Construction features are all construction materials are stainless steel, glass, or fluorocarbon plastics; the piston seal is a very flexible welded stainless-steel bellows; the chamber can be made very clean by heating under vacuum, and it is compatible …


Crystal Perfection Of Hgi2 Studied By Neutron And Gamma-Ray Diffraction, W. (William) B. Yelon, R. W. Alkire, M. M. Schieber, L. Van Den Berg, S. E. Rasmussen, H. Christensen, J. R. Schneider Dec 1981

Crystal Perfection Of Hgi2 Studied By Neutron And Gamma-Ray Diffraction, W. (William) B. Yelon, R. W. Alkire, M. M. Schieber, L. Van Den Berg, S. E. Rasmussen, H. Christensen, J. R. Schneider

Physics Faculty Research & Creative Works

The crystalline perfection of wire sawn pieces of vapor grown single crystals of mercuric iodide was compared with the perfection of (00l) cleaved sections of the same crystal from which nuclear radiation detectors have been fabricated. The crystalline perfection was studied using neutron and gamma-ray diffraction rocking curves. Most of the gamma-ray data were obtained using a high intensity source of 153Sm gamma rays with a wavelength of λ = 0.12 Å. Some of the data were obtained using highly penetrating 198Au gamma rays with a shorter wavelength of λ = 0.03 Å. The neutrons had a wavelength of λ …


Orientation Of Atoms Excited By Charged Particles At High Impact Energies, Don H. Madison, Kieth H. Winters Oct 1981

Orientation Of Atoms Excited By Charged Particles At High Impact Energies, Don H. Madison, Kieth H. Winters

Physics Faculty Research & Creative Works

A perturbation-expansion approach is used to examine the sign of the orientation vector as a function of scattering angle and projectile charge. It is shown that for small angles, the sign of the orientation vector is different for oppositely charged projectiles consistent with the prediction of the classical grazing model. At large angles, on the other hand, the orientation vector for oppositely charged projectiles is shown to have the same sign.


The Water Monomer On The Prism Face Of Ice And Above A Four Layer Ice Basal Face Ledge: An Effective Pair Potential Model, Barbara N. Hale, Jerry Kiefer, Carolyn A. Ward Aug 1981

The Water Monomer On The Prism Face Of Ice And Above A Four Layer Ice Basal Face Ledge: An Effective Pair Potential Model, Barbara N. Hale, Jerry Kiefer, Carolyn A. Ward

Physics Faculty Research & Creative Works

A previous study of the water monomer on the basal faces of ice is extended to consider the interaction of the water molecule with a rigid prism face of ice and with an ice basal face ledge. The effective central force H2O-H2O potentials of Stillinger and Rahman are used to generate maximal binding energy surfaces for the H2O adsorbed on the sample substrates. The results indicate that the prism face of ice binds the water molecule more strongly than the basal faces, and the step on the basal face serves to expose high binding …


Structural And Magnetic Properties Of Co(Urea)₂Cl₂·2h₂O: A Two-Dimensional Lsing System With Hidden Canting, Richard Lewis Carlin, Kyong O. Joung, Andries Van Der Bilt, H. Den Adel, Charles J. O'Connor, Ekkehard Sinn Jul 1981

Structural And Magnetic Properties Of Co(Urea)₂Cl₂·2h₂O: A Two-Dimensional Lsing System With Hidden Canting, Richard Lewis Carlin, Kyong O. Joung, Andries Van Der Bilt, H. Den Adel, Charles J. O'Connor, Ekkehard Sinn

Chemistry Faculty Research & Creative Works

The characterization of Co(urea)2Cl2·2H2O is reported. The crystal structure at ambient temperatures yields the following information: the chlorine, water, and urea group are coordinated, the urea being bound via the oxygen, to form an octahedral environment about the metal atom. Intermolecular hydrogen bonds between the coordinated chlorine and water ligands produce parallel infinite sheets which provide a two-dimensional exchange pathway. The sheets are separated by the urea ligands and may be considered as magnetically isolated from one another. Crystal data: space group P21/c, Z = 2, α = 7.397 (3) Å, b …


Electron Capture At Very Small Scattering Angles From Atomic Hydrogen By 25-125-Kev Protons, Paul J. Martin, D. M. Blankenship, Thomas J. Kvale, E. Redd, Jerry Peacher, John T. Park Jun 1981

Electron Capture At Very Small Scattering Angles From Atomic Hydrogen By 25-125-Kev Protons, Paul J. Martin, D. M. Blankenship, Thomas J. Kvale, E. Redd, Jerry Peacher, John T. Park

Physics Faculty Research & Creative Works

Differential cross sections for electron capture in collisions between protons and hydrogen atoms have been experimentally determined for incident proton energies of 25, 60, and 125 keV in the center-of-mass scattering-angle range of 0-3 mrad. The experimental results compare more favorably with the results of both a multistate and a two-state calculation than with the results of a continuum distorted-wave-approximation calculation. There is no evidence of a Jackson-Schiff-type minimum.


Differential Cross Sections For Electron Capture From Helium By 25- To 100-Kev Incident Protons, Paul J. Martin, Kenneth E. Arnett, D. M. Blankenship, Thomas J. Kvale, Jerry Peacher, E. Redd, V. C. Sutcliffe, John T. Park, Chiidong Lin, Jim H. Mcguire Jun 1981

Differential Cross Sections For Electron Capture From Helium By 25- To 100-Kev Incident Protons, Paul J. Martin, Kenneth E. Arnett, D. M. Blankenship, Thomas J. Kvale, Jerry Peacher, E. Redd, V. C. Sutcliffe, John T. Park, Chiidong Lin, Jim H. Mcguire

Physics Faculty Research & Creative Works

Experimentally and theoretically determined differential cross sections are reported for electron capture in collisions of protons with helium atoms for incident proton energies of 25, 30, 50, and 100 keV and for center-of-mass scattering angles of 0.0 to 2.0 mrad. The magnitudes of the experimentally determined differential cross sections decrease from 10-10 to 10-12 cm2/sr within the 0.0-0.8-mrad range of the center-of-mass scattering angle. At approximately 0.8 mrad a distinct change in the slope of the differential cross section is observed. The experimental results which are for capture into all bound states of hydrogen are compared …


A Topological Analysis Of The Complexity Of Computer Programs With Less Than Three Binary Branches, Warren Harrison, Kenneth I. Magel Apr 1981

A Topological Analysis Of The Complexity Of Computer Programs With Less Than Three Binary Branches, Warren Harrison, Kenneth I. Magel

Computer Science Faculty Research & Creative Works

No abstract provided.


Angular Differential And Total Cross Sections For The Excitation Of Atomic Hydrogen To Its N=2 State By Helium Ions, Judith E. Aldag, Jerry Peacher, Paul J. Martin, V. C. Sutcliffe, Jacob M. George, E. Redd, Thomas J. Kvale, D. M. Blankenship, John T. Park Mar 1981

Angular Differential And Total Cross Sections For The Excitation Of Atomic Hydrogen To Its N=2 State By Helium Ions, Judith E. Aldag, Jerry Peacher, Paul J. Martin, V. C. Sutcliffe, Jacob M. George, E. Redd, Thomas J. Kvale, D. M. Blankenship, John T. Park

Physics Faculty Research & Creative Works

Differential cross sections for 15-100 keV He+ excitation of atomic hydrogen to its n=2 level have been determined for c.m. angles from 0 to 8 mrad. The differential cross sections are obtained from an analysis of the angular distribution of the scattered ions which have lost an energy corresponding to the excitation of the target to its n=2 level. The shape of the differential cross section changes rapidly with increasing incident energy. At 15 keV, the differential cross section falls off by a factor of 5 in 6 mrad. At 100 keV, the differential cross section decreases by nearly …


Recommendations For Master's Level Programs In Computer Science: A Report Of The Acm Curriculum Committee On Computer Science, Kenneth I. Magel, Richard H. Austing, Alfs Berztiss, Gerald L. Engel, John Wesley Hamblen, A. A.J. Hoffmann, Robert Mathis Mar 1981

Recommendations For Master's Level Programs In Computer Science: A Report Of The Acm Curriculum Committee On Computer Science, Kenneth I. Magel, Richard H. Austing, Alfs Berztiss, Gerald L. Engel, John Wesley Hamblen, A. A.J. Hoffmann, Robert Mathis

Computer Science Faculty Research & Creative Works

The ACM Committee on Curriculum in Computer Science has spent two years investigating master's degree programs in Computer Science. This report contains the conclusions of that effort. Recommendations are made concerning the form, entrance requirements, possible courses, staffing levels, intent, library resources, and computing resources required for an academic, professional, or specialized master's degree. These recommendations specify minimum requirements which should be met by any master's programs. The Committee believes that the details of a particular master's program should be determined and continually updated by the faculty involved. A single or a small number of model programs are not as …


Effect Of Polarization And Absorption On Differential Cross Sections And Angular Correlation Parameters For Electron Excitation Of Helium, M. E. Stewart, Don H. Madison Feb 1981

Effect Of Polarization And Absorption On Differential Cross Sections And Angular Correlation Parameters For Electron Excitation Of Helium, M. E. Stewart, Don H. Madison

Physics Faculty Research & Creative Works

The effects of local polarization and absorption potentials on differential cross sections and angular correlation parameters are studied within the distorted-wave approximation for electron excitation of the 2 1P state of helium. For examining the effect of local polarization, we have compared a recent numerical self-consistent adiabatic polarization potential for helium with the commonly used hydrogenic adiabatic polarization potential. Different radial regions for the polarization potential were studied to determine their contribution to the overall effect of polarization. Calculations are also presented which show the effects of different strengths for a local absorption potential.


Regular Expressions In A Program Complexity Metric, Kenneth I. Magel Jan 1981

Regular Expressions In A Program Complexity Metric, Kenneth I. Magel

Computer Science Faculty Research & Creative Works

No abstract provided.


A Complexity Measure Based On Nesting Level, Warren A. Harrison, Kenneth I. Magel Jan 1981

A Complexity Measure Based On Nesting Level, Warren A. Harrison, Kenneth I. Magel

Computer Science Faculty Research & Creative Works

No abstract provided.


A Suggested Course In Introductory Computer Programming, Warren A. Harrison, Kenneth I. Magel Jan 1981

A Suggested Course In Introductory Computer Programming, Warren A. Harrison, Kenneth I. Magel

Computer Science Faculty Research & Creative Works

Introductory programming courses have long been a popular topic of discussion. Often it is either the only computer course a student takes, or it is the foundation upon which all further training in computer science is built. The usual goal of such a course is to introduce the student to the use of a computer to solve simple problems in his or her particular discipline. Generally, the method of presenting the material may be separated into two distinct schools of thought, which we have termed the "Black Box School of Thought" and the "White Box School of Thought". In this …


Classes Of L¹-Convergence Of Fourier And Fourier-Stieltjes Series, Časlav V. Stanojevic Jan 1981

Classes Of L¹-Convergence Of Fourier And Fourier-Stieltjes Series, Časlav V. Stanojevic

Mathematics and Statistics Faculty Research & Creative Works

It is shown that the Fomin class FP (1

< 2) is a subclass of C ∩ B V, where C is the Garrett-Stanojevic class and B V the class of sequences of bounded variation. Wider classes of Fourier and Fourier-Stieltjes series are found for which an lg n - o(1), n → ∞, is a necessary and sufficient condition for L1-convergence. For cosine series with coefficients in B V and n∆an = 0(1), n → ∞, necessary and sufficient integrability conditions are obtained. © 1981 American Mathematical Society.


Integral Identities Of Norms And Characterization Of Inner Product Spaces, Časlav V. Stanojevlć, Ana M. Suchanek Jan 1981

Integral Identities Of Norms And Characterization Of Inner Product Spaces, Časlav V. Stanojevlć, Ana M. Suchanek

Mathematics and Statistics Faculty Research & Creative Works

Integral identities of norms over compact groups are used to characterize inner product spaces. These integral identities also generalize the Penico- Stanojevic [1] integral form of the parallelogram law. © 1981 American Mathematical Society. © 1981 American Mathematical Society.


Neutron Activation Analysis Of Nuclides From Stellar And Man-Induced Nuclear Reactions, Lawrence Lee Oliver Jan 1981

Neutron Activation Analysis Of Nuclides From Stellar And Man-Induced Nuclear Reactions, Lawrence Lee Oliver

Doctoral Dissertations

"Neutron activation and γ-counting were used to determine the relative abundances of six stable tellurium isotopes in the acid-etched residues of the Allende meteorite. The results were correlated with the isotopic compositions of xenon and the elemental abundances of helium and neon in similarly prepared residues. Nucleosynthesis appears to be the only viable explanation for the anomalous isotopic and elemental compositions observed in these residues. Our results suggest that the solar system condensed from an isotopically and chemically zoned nebula that was produced by the explosion of a supernova, concentric with the present sun.

A combination of neutron activation and …