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An Apparatus For Measuring The Thermal Conductivity Of Cast Insulation Materials, Christine A. Wilkins, Robert L. Ash Jul 1980

An Apparatus For Measuring The Thermal Conductivity Of Cast Insulation Materials, Christine A. Wilkins, Robert L. Ash

Mechanical & Aerospace Engineering Faculty Publications

A steady-state apparatus has been developed for measuring the thermal conductivity of cast materials. The design has employed a novel thermal symmetry arrangement which can permit total electrical isolation of the test material from its surroundings. © 1980 American Institute of Physics

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Inversion Of The Nonlinear Equations Of Reflection Ellipsometry For Uniaxial Crystals In Symmetrical Orientations, M. Elshazly-Zaghloul, R. M.A. Azzam Jul 1980

Inversion Of The Nonlinear Equations Of Reflection Ellipsometry For Uniaxial Crystals In Symmetrical Orientations, M. Elshazly-Zaghloul, R. M.A. Azzam

Electrical Engineering Faculty Publications

The complex ordinary (No) and extraordinary (Ne) refractive indices of an absorbing uniaxial crystal can be determined using reflection ellipsometry. The measurements are taken with the optic axis parallel and perpendicular to the crystal’s surface. The equations obtained are solved without resort to iterative methods; No and Ne are determined separately. Sixteen solution sets (No, Ne) are obtained and the correct solution can be easily identified. We present an optimum angle of incidence that minimizes the relative errors in No and Ne.

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Pressure Dependence Of Fluorescent And Photolytic Interferences In Ho Detection By Laser-Excited Fluorescence, Thomas M. Hard, Robert J. O'Brien, T. B. Cook Jul 1980

Pressure Dependence Of Fluorescent And Photolytic Interferences In Ho Detection By Laser-Excited Fluorescence, Thomas M. Hard, Robert J. O'Brien, T. B. Cook

Chemistry Faculty Publications and Presentations

In the measurement of HO concentrations by laser-excited fluorescence, expansion of the sampled air offers a way to reduce fluorescent and photolytic interference by other species. The decrease in [HO] upon expansion is balanced by an increase in HO fluorescence yield over a wide range of pressures. Background air fluorescence is reduced if the responsible species have fluorescence yields higher than those of HO. Preliminary experiments indicate that most of the fluorescence observed in laboratory air is due to such species. Upon expansion, the suppression of fluorescent interference can be no greater than the reduction in pressure, whereas the suppression …

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Studies Of The Reorientational Relaxation Of Pyridine In Water By Depolarized Rayleigh Light Scattering, C. H. Wang, Scott L. Whittenburg, P. A. Lund, D. H. Christensen Apr 1980

Studies Of The Reorientational Relaxation Of Pyridine In Water By Depolarized Rayleigh Light Scattering, C. H. Wang, Scott L. Whittenburg, P. A. Lund, D. H. Christensen

Chemistry and Biochemistry Faculty Publications

The depolarized Rayleigh spectra of aqueous solutions of pyridine have been studied using a high‐finesse Fabry–Perot interferometer as a function of temperature and concentration. The Rayleigh relaxation times are found to have a complex concentration and viscosity dependence. The classical Stokes–Einstein–Debye equation for molecular reorientation breaks down in this system. The Rayleigh relaxation time of pyridine molecules is not determined by the macroscopic shear viscosity of the solution. The specific interaction due to the formation of hydrogen bonds between pyridine and water molecules plays a very important role in affecting the relaxation time. At a fixed temperature the plot of …

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Partial Chemical Equilibrium In Fluid Dynamics, John D. Ramshaw Apr 1980

Partial Chemical Equilibrium In Fluid Dynamics, John D. Ramshaw

Physics Faculty Publications and Presentations

An analysis is given for the flow of a multicomponent fluid in which an arbitrary number of chemical reactions may occur, some of which are in equilibrium while the others proceed kinetically. The primitive equations describing this situation are inconvenient to use because the progress rates ω [subscript s] for the equilibrium reactions are determined implicitly by the associated equilibrium constraint conditions. Two alternative equivalent equation systems that are more pleasant to deal with are derived. In the first system, the ω [subscript s] are eliminated by replacing the transport equations for the chemical species involved in the equilibrium reactions …

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Potential Use Of Chemical Spot Test Method For Submicron Aerosol Sizing, Paul C. Yue, Josef Podzimek Mar 1980

Potential Use Of Chemical Spot Test Method For Submicron Aerosol Sizing, Paul C. Yue, Josef Podzimek

Physics Faculty Research & Creative Works

A submicron particle, which is too small to be observed in an optical microscope, may form an observable spot on a chemically prepared substrate of the collector. The size of the spot or "Liesegang circle" is related to the aerodynamic diameter of the particle through a magnification factor. This paper presents the experimental results of the study of this factor using sodium chloride aerosol in the size range of 0.5 to 2 pm which has not previously been studied. We calibrated a cylindrical centrifuge with known sized latex particles. A relationship between the aerodynamic diameter and the deposition length is …

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Angular Differential Cross Sections For Excitation Of Atomic Hydrogen To The N=2 Level By Proton Impact, John T. Park, John E. Aldag, Jerry Peacher, Jacob M. George Mar 1980

Angular Differential Cross Sections For Excitation Of Atomic Hydrogen To The N=2 Level By Proton Impact, John T. Park, John E. Aldag, Jerry Peacher, Jacob M. George

Physics Faculty Research & Creative Works

Differential cross sections for 15-145-keV proton impact excitation of atomic hydrogen to the n=2 level have been determined for center-of-mass scattering angles 0 to 1.2 mrad. The cross sections were obtained from an analysis of the angular distribution of protons which had lost an energy corresponding to the excitation of atomic hydrogen to its n=2 level. The differential cross sections obtained are in rather good agreement with available coupled-state calculations as well as the simpler Glauber-approximation calculations. However, at the larger scattering angles the cross sections obtained from the theoretical treatments appear to decrease more rapidly than the experimental data.

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Four-Color And Hβ Photometry Of Stars In The Galactic Cluster Ngc 129, Edward G. Schmidt Jan 1980

Four-Color And Hβ Photometry Of Stars In The Galactic Cluster Ngc 129, Edward G. Schmidt

Edward Schmidt Publications

Four-color and photometry has been obtained for 22 stars in the field of the open cluster NGC 129. Based on this photometry, the membership of these stars in the cluster is discussed and it is found that many are field stars. The color excesses for cluster members obtained here range from E(b – y) = 0.207 to 0.513 and are larger than those found from previous UBV photometry. It has been suggested that this cluster contains a nonvariable Cepheid strip star. However, the present reddening places this star at the edge of the instability strip. A true …

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Plasma Line Measurements At Chatanika With High-Speed Correlator And Filter Bank, W. Kofman, Vincent B. Wickwar Jan 1980

Plasma Line Measurements At Chatanika With High-Speed Correlator And Filter Bank, W. Kofman, Vincent B. Wickwar

All Physics Faculty Publications

In the spring and fall of 1978 we made an extensive series of plasma line and correlative observations with the Chatanika incoherent scatter radar. To make these measurements, we greatly modified the radar receiving system. In addition to enlarging the plasma line filter bank the most significant change was the incorporation of a high-speed correlator provided by the French. This was the first use of a correlator in a monostatic radar to obtain the intensity spectra of naturally occurring plasma lines. In this paper we develop the signal-processing theory that we use to obtain the plasma line intensities from these …

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A Comparison Of Model Predictions For Plasma Convection In The Northern And Southern Polar Regions, Jan Josef Sojka, W. J. Raitt, Robert W. Schunk Jan 1980

A Comparison Of Model Predictions For Plasma Convection In The Northern And Southern Polar Regions, Jan Josef Sojka, W. J. Raitt, Robert W. Schunk

All Physics Faculty Publications

We have presented model calculations to show how the plasma flow distributions in the northern and southern polar regions differ when viewed from a geographic inertial frame. This reference frame was selected because it is the natural frame for geophysical plasma flow measurements, there being well-known velocity corrections for either satellite or ground-based observations. Although the magnetic invariant latitude, magnetic local time reference frame is better suited to studying magnetospheric processes, a transformation from the geographic inertial frame to this magnetic frame requires both a spatial and velocity transformation, and since the latter correction has generally been neglected, we prefer …

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A Graphical Method For Calculating First Order Transition Matrices For Open-Shell Atoms In The Random Phase Approximation, Anthony F. Starace, Siamak Shahabi Jan 1980

A Graphical Method For Calculating First Order Transition Matrices For Open-Shell Atoms In The Random Phase Approximation, Anthony F. Starace, Siamak Shahabi

Anthony F. Starace Publications

A graphical procedure is presented for calculating first order transition matrices for a general (open-shell) atom. The first order transition matrix may be used to calculate matrix elements of a general one-body operator of rank λ in orbital space and σ in spin space. In the random phase approximation we obtain a set of N + N′ coupled differential equations for N final state radial functions and N′ initial state radial functions which completely determine the first order transition matrix for an atomic system having N final state channels. (The relation of N′ to N is dependent on the atomic …

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Angular And Energy Distribution Of Electrons From 15- To 150-Kev H0+He Collisions, M. Eugene Rudd, J. S. Risley, J. Fryar, R. G. Rolfes Jan 1980

Angular And Energy Distribution Of Electrons From 15- To 150-Kev H0+He Collisions, M. Eugene Rudd, J. S. Risley, J. Fryar, R. G. Rolfes

M. Eugene Rudd Publications

An electrostatic analyzer positioned at various angles has been used to measure absolute values of cross sections for electron production in collisions of neutral hydrogen atoms with helium as a function of the angle and energy of the ejected electrons. These cross sections are compared with corresponding ones for proton and electron impact to infer the mechanisms of electron production. A prominent peak in the energy distribution due to electron loss from the projectile occurs at an electron velocity equal to that of the projectile. At very low electron energies the similarity of the energy distribution to that due to …

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Nonequilibrium Thermodynamics Of Fuel Cells: Heat Release Mechanisms And Voltage, Gerald Wilemski Jan 1980

Nonequilibrium Thermodynamics Of Fuel Cells: Heat Release Mechanisms And Voltage, Gerald Wilemski

Physics Faculty Research & Creative Works

Nonequilibrium thermodynamics is used to analyze the spatial distribution of heat release mechanisms occurring in fuel cells operating under load in nonisothermal steady states. Novel contributions to heat release in the bulk electrolyte are found which are analogous to Peltier and Thomson effects in metallic conductors. Expresions for the heat release at individual electrodes are presented. An equation for the voltage of these cells is also derived. © 1980 American Institute of Physics.

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Forbidden Lines Of Np^Q Ions. I. Detailed Balance And Line Intensity Ratios, Menas Kafatos, J. P. Lynch Jan 1980

Forbidden Lines Of Np^Q Ions. I. Detailed Balance And Line Intensity Ratios, Menas Kafatos, J. P. Lynch

Mathematics, Physics, and Computer Science Faculty Articles and Research

Ground state forbidden transitions of np^q ions of C, N, 0, Ne, Mg, Si, S, and Fe can provide important information on the state of cosmic ionized gases. Wavelengths of these lines are in the far- and near-UV visible and near-- and far-IR regions of the spectrum. The line intensity ratios of particular transitions in q = 2, 4 ions can provide information on the temperature of the gas and in q = 3 ions information on the density of the gas. In the present work we have tabulated the line intensities of 95 transitions of these ions, which include …

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Effects Of Beam Polarization On Λ And K0 Inclusive Production In Pp Interactions At 12 Gev/C, R. L. Eisner, William J. Fickinger, J. A. Malko, D. K. Robinson, V. A. Sreedhar Jan 1980

Effects Of Beam Polarization On Λ And K0 Inclusive Production In Pp Interactions At 12 Gev/C, R. L. Eisner, William J. Fickinger, J. A. Malko, D. K. Robinson, V. A. Sreedhar

Faculty Scholarship

Inclusive production of Λ and K0 in pp interactions at 12 GeV/c has been studied in an exposure of the Argonne National Laboratory 12-foot bubble chamber to a 50% transversely polarized proton beam. Beam-polarization-induced asymmetries are observed for both K0 and Λ production in the forward direction.

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Angular Differential Cross Sections For Excitation Of Atomic Hydrogen To Its N=2 Level By Impact Of 15-100 Kev He⁺ Ions, John Eldon Aldag Jan 1980

Angular Differential Cross Sections For Excitation Of Atomic Hydrogen To Its N=2 Level By Impact Of 15-100 Kev He⁺ Ions, John Eldon Aldag

Doctoral Dissertations

Differential cross sections Ear excitation of atomic hydrogen to its n = 2 level by 15-100 keV He+ ions have been determined for cm. angles from Oto 8 m rad. The cross sections were obtained from an analysis of the angular distribution of the scattered ions which had 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 cross section falls off by a factor of 5 in 6 m rad. At 100 keV, the cross section …

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Large-Angle Electron-Photon Coincidence Experiment In Atomic Hydrogen, E. Weigold, L. Frost, K. (Kaare) J. Nygaard Jan 1980

Large-Angle Electron-Photon Coincidence Experiment In Atomic Hydrogen, E. Weigold, L. Frost, K. (Kaare) J. Nygaard

Physics Faculty Research & Creative Works

1s-2p excitation in hydrogen has been studied by observing the angular correlation of Lyman photons detected in coincidence with inelastically scattered electrons at 54.4 eV incident energy. The electron scattering angles ranged from 10°to 133°; the results at scattering angles larger than 20°cannot be explained by currently available theories. © 1980 The American Physical Society.

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A Molecular Dynamics Study Of The Stability Of Small Prenucleation Water Clusters, Tze-Shan Chen Jan 1980

A Molecular Dynamics Study Of The Stability Of Small Prenucleation Water Clusters, Tze-Shan Chen

Doctoral Dissertations

"The dynamical stability and internal energy distribution of prenucleation water embryos have been studied by the molecular dynamic's method. Water clusters containing either five or twenty molecules were chosen to represent prenucleation embryos of small or intermediate size. A central force potential model of water which allows energy to be absorbed into intramolecular modes so that bond lengths and bond angles could adjust to changes in molecular environments was employed to describe the interaction between all pairs of atoms. The motion of the molecules was followed for extended time periods (of the order of several picoseconds) at each of a …

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Amorphous-Damage Depth Distributions And The Amorphization Of Silicon By Ion Bombardment, Joseph Sadowski Jan 1980

Amorphous-Damage Depth Distributions And The Amorphization Of Silicon By Ion Bombardment, Joseph Sadowski

Doctoral Dissertations

"Depth distributions of the radiation damage in moderately to heavily ion bombarded silicon was obtained in the following manner: The electron spin resonance signal from an ion bombarded silicon target was measured. This ESR signal was proportional to the amount of amorphous silicon present in the target. A thin oxide of specified thickness was then grown on the surface of the target by anodic oxidation and subsequently stripped off in a HF etch. The depth of the stripped impression below the unoxidized surface was measured using a multibeam interferometer. The amorphous ESR signal was again measured, and the strip / …

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Nickel Carbide: Its Formation And Characterization By Transmission Electron Diffraction, Auger Electron Spectroscopy And Electron Spectroscopy For Chemical Analysis, J. Kleefeld, L. L. Levenson Dec 1979

Nickel Carbide: Its Formation And Characterization By Transmission Electron Diffraction, Auger Electron Spectroscopy And Electron Spectroscopy For Chemical Analysis, J. Kleefeld, L. L. Levenson

Physics Faculty Research & Creative Works

Nickel carbide (NiC3) films are formed by the carburization of nickel films in CO at 350°C. The presence of Ni3C is demonstrated by transmission electron diffraction. The carbon Auger electron signal of Ni3C is identical with the carbon Auger spectra attributed to Ni3C by previous authors. The position of the C 1s electron spectroscopy for chemical analysis peak is within 1 eV of the C 1s peak produced by graphite. The grain size of polycrystalline Ni3C is significantly larger than the grain size of the nickel film from which it is grown. © 1979.

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The Neutron Total Cross Section Of 208Pb, Lawrence J. Satkowiak Dec 1979

The Neutron Total Cross Section Of 208Pb, Lawrence J. Satkowiak

Masters Theses

No abstract provided.

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Conductive Strontium Titanate Layers Produced By Boron-Ion Implantation, Connie M. Cooper, P. S. Nayar, Edward Boyd Hale, Robert Gerson Dec 1979

Conductive Strontium Titanate Layers Produced By Boron-Ion Implantation, Connie M. Cooper, P. S. Nayar, Edward Boyd Hale, Robert Gerson

Physics Faculty Research & Creative Works

The ion implantation of boron has been found to be an effective method for increasing the conductivity of strontium titanate. A highly conductive layer was formed by implantations at doses of 3.6x1016 to 1.0x1017 ions/cm2, using an accelerating voltage of 100 kV, corresponding to a boron range of about 300 nm. The conductivity of the implanted layer was found to be further enhanced by about four orders of magnitude after annealing at 225 °C. The surface resistivity attained was typically 1000 Ω/square at room temperature. The resistance increased with rising temperature between 77 and 500 K. All samples were found …

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Model For Fe2+ Intracenter-Induced Photoconductivity In Inp: Fe, David C. Look Nov 1979

Model For Fe2+ Intracenter-Induced Photoconductivity In Inp: Fe, David C. Look

Physics Faculty Publications

We have observed a broad, room-temperature photoconductivity band, with a peak at 0.44 eV, in Fe-doped InP. This band is attributed to an Fe2+ intracenter optical excitation, followed by a thermal excitation to the conduction band. We derive a photoconductivity expression which takes into account optical and thermal transitions between impurity ground and excited states, within the band gap, and the conduction band. The parameters yielded by the model include a thermal excitation prefactor of 1×1011 sec-1, an electron capture cross section of 1×10-15 cm2, a spontaneous recombination coefficient of 1×106 sec …

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The Moral Equivalent Of Business As Usual, Harry A. Brown Oct 1979

The Moral Equivalent Of Business As Usual, Harry A. Brown

UMR-DNR Conference on Energy

No abstract provided.

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Lasers In Energy Research, Kaare J. Hygaard, Howard L. Brooks, Rafael A. Sierra, Stephen R. Foltyn Oct 1979

Lasers In Energy Research, Kaare J. Hygaard, Howard L. Brooks, Rafael A. Sierra, Stephen R. Foltyn

UMR-DNR Conference on Energy

No abstract provided.

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Spin-Glass-Like Behavior In Very Dilute Pdfe At Very Low Temperatures, Richard A. Webb, G. W. Crabtree, J. J. Vuillemin Sep 1979

Spin-Glass-Like Behavior In Very Dilute Pdfe At Very Low Temperatures, Richard A. Webb, G. W. Crabtree, J. J. Vuillemin

Faculty Publications

Measurements of the electrical resistivity of palladium, residual resistivity ratio ∼22 500, containing 1.7 ppm of Fe have been made from 5.5 K to 1.8 mK. 15 Hz ac susceptibility measurements from 1 K to 1.8 mK together with the resistivity data suggest that a transition into a spin-glass state occurs near 7 mK.

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Doubly Differential Cross Sections For Proton-Impact Ionization Of Argon, Don H. Madison, Steven Trent Manson Sep 1979

Doubly Differential Cross Sections For Proton-Impact Ionization Of Argon, Don H. Madison, Steven Trent Manson

Physics Faculty Research & Creative Works

Proton-impact-ionization cross sections for argon which are differential in the energy and angle of the ejected electron have been calculated within the framework of the Born approximation using both Hartree-Slater and Hartree-Fock wave functions for the ejected electron. Results of the two types of calculations are compared with each other and with experiment. Differential cross sections for all five sub shells of argon are examined and particular attention is given to some interesting features of the K-shell cross sections. The range of applicability of the theoretical models is discussed.

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Study Of The Reaction P↑P→∆⁺⁺ At 6 Gev/C With Polarized Beam, R. L. Eisner, William J. Fickinger, J. A. Malko, D. K. Robinson, V. A. Sreedhar Aug 1979

Study Of The Reaction P↑P→∆⁺⁺ At 6 Gev/C With Polarized Beam, R. L. Eisner, William J. Fickinger, J. A. Malko, D. K. Robinson, V. A. Sreedhar

Faculty Scholarship

We have studied the reaction p↑p→nΔ++ at 6 GeV/c incident momentum in which the incident protons are 60% transversely polarized. The experiment used the Argonne National Laboratory Zero Gradient Synchrotron polarized beam and the 12-foot hydrogen bubble chamber. We report on about 6000 Δ++ events, with the Δ++ produced in the backward hemisphere in the c.m. system. Spin-density matrix elements as a function of momentum transfer are presented and small beam-polarization-induced effects are described.

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21st Rocky Mountain Conference On Analytical Chemistry Jul 1979

21st Rocky Mountain Conference On Analytical Chemistry

Rocky Mountain Conference on Magnetic Resonance

Abstracts and meeting program from the 21st annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy and the Rocky Mountain Chromatography Discussion Group. Held in Denver, Colorado, July 30 - August 1, 1979.

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Photometric Measurements Of Thin Tracks In Nuclear Emulsion, Robert Katz Jul 1979

Photometric Measurements Of Thin Tracks In Nuclear Emulsion, Robert Katz

Robert Katz Publications

Difficulties observed in the application of track theory to CNO particles are attributed to problems in the application of a light scattering correction in microphotometry.

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