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Explicit Determination Of Thickness Of A Transparent Film On A Transparent Substrate From Angles Of Incidence Of Equal P And S Reflectivities, R. M.A. Azzam Oct 1981

Explicit Determination Of Thickness Of A Transparent Film On A Transparent Substrate From Angles Of Incidence Of Equal P And S Reflectivities, R. M.A. Azzam

Electrical Engineering Faculty Publications

No abstract provided.


Experimental Investigation Of A Rectangular Surface Thermal Plume, Li-Cheng Chu Oct 1981

Experimental Investigation Of A Rectangular Surface Thermal Plume, Li-Cheng Chu

Mechanical & Aerospace Engineering Theses & Dissertations

An experimental investigation of the three dimensional mean temperature distribution of a rectangular buoyant surface thermal plume has been conducted for a range of buoyancies, velocity ratios, Reynolds numbers, and for various turbulence generating screens in the crossflow. This study has been motivated by a concern about the applicability of laboratory model data for predicting prototype plume behavior.

A large scale model has been built to study a buoyant, rectangular surface thermal plume which enters at right angles to a constant temperature uniform crossflow of depth equal to that of the plume. A large water tank and flume with weir …


23rd Rocky Mountain Conference Aug 1981

23rd Rocky Mountain Conference

Rocky Mountain Conference on Magnetic Resonance

Abstracts and meeting program from the 23rd annual meeting of the Rocky Mountain Conference, co-sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy and the Rocky Mountain Chromatography Discussion Group. Held in Denver, Colorado, August 2-6, 1981.


A Study Of The Films Produced By The Aluminum/Water Reaction Using Rutherford Backscattering Spectroscopy, Reed L. Shilts Aug 1981

A Study Of The Films Produced By The Aluminum/Water Reaction Using Rutherford Backscattering Spectroscopy, Reed L. Shilts

Masters Theses

This work compares the action of pure water to various aqueous electrolytes on aluminum surface film formation at about 100°C. The electrolytes were pure water with various inhibitor ions added. The ions were nitrate, tungstate, borate, molybdate, silicate, phosphate, a mixture of nitrate and molybdate, and a mixture of silicate and molybdate. The investigative technique was Rutherford backscattering spectroscopy (RBS) using 2 MeV alpha particles with an annular detector set at 180 degrees for maximum elemental resolution. RBS was chosen for this investigation because it offers in an easily interpretable manner a relatively fast and semi-quantitative method of analysis of …


Detection Of Vibrationally Excited Nitrogen By Trapped Electron And Electron Transmission Methods, J.A. Michejda, L.J. Dube, Paul Burrow May 1981

Detection Of Vibrationally Excited Nitrogen By Trapped Electron And Electron Transmission Methods, J.A. Michejda, L.J. Dube, Paul Burrow

Paul Burrow Publications

Two techniques for detection of vibrationally excited nitrogen using low-energy electron scattering are described. The first technique uses the trapped electron method to observe excitation from N2ν into the B3Пg state near threshold. From the known Franck-Condon factors, the contribution from excited vibrational levels may be unfolded. The second technique employs the electron transmission method to detect sharp structure in the total scattering cross section resulting from the formation of temporary negative ions. Because of uncertainties in the total scattering cross sections from each of the vibrational levels, the transmission method is less accurate than …


A Critical Study Of Nonlinear Echo Phenomena, Monish Ranjan Chatterjee May 1981

A Critical Study Of Nonlinear Echo Phenomena, Monish Ranjan Chatterjee

Electrical and Computer Engineering Faculty Publications

The present thesis attempts to give a concise and critical account of the evolution of the echo phenomena over the last thirty years. Starting with spin and photon echoes, which were among the earliest to be observed and studied, the thesis explores the experimental findings and the models proposed in connection with the more contemporary echo experiments, viz. those involving electroacoustic or polarization echoes in single and polycrystalline piezoelectric materials and in powders. Although the investigations regarding the various mechanisms of short and long term echo formation are by no means complete, a coherent picture is beginning to emerge as …


University-School Cooperation, Herman Feshbach, Robert Fuller Apr 1981

University-School Cooperation, Herman Feshbach, Robert Fuller

Robert G. Fuller Publications

We have a growing concern with the deterioration in both the quality and quantity of secondary physics education in the US. These concerns have recently been addressed by an APS panel chaired by Gertrude S. Goldhaber.


Autooscillations In Zinc, Manfred Wuttig, Alex Aning, Tetsuro Suzuki Jan 1981

Autooscillations In Zinc, Manfred Wuttig, Alex Aning, Tetsuro Suzuki

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.


Synchronized Slide-Tapes In The Physics Laboratory, Loren Quan Jan 1981

Synchronized Slide-Tapes In The Physics Laboratory, Loren Quan

University of the Pacific Theses and Dissertations

Media play a large part in most of our daily lives. We watch television; we go to the movies; we listen to the radio. For years educators have been adapting media-related technological advancements for the purpose of teaching in the classroom. Here at the Physics Department of the University of the Pacific, we have adapted the medium of synchronized slide-tapes for use in the laboratory component of our calculus-based introductory physics course.


High Resolution Laser Absorption Spectroscopy Of Ozone Near 1129.4 Cm-1, Lawrence N. Majorana Dec 1980

High Resolution Laser Absorption Spectroscopy Of Ozone Near 1129.4 Cm-1, Lawrence N. Majorana

Physics Theses & Dissertations

A Beer's Law experiment was performed with a tunable laser to determine self broadened line shape parameters of one infrared absorption ozone line in the v1 band for ten pressures from 0.26 to 6.29 Torr at 285K. SO2 line positions were used for wavelength calibration. Line shapes were iteratively fitted to the Voigt function at a Doppler width of 29.54 MHz (HWHM) resulting in values for the integrated line• strength, ( S), of (0.144 +/- 0.007 ) x ·10-20 cm-1/molecule cm-2, line center frequency, (υο) of 1129.426 cm-1 and the Lorentzian contributions to half width, (α …


Thermal Decomposition Kinetics Of Asf5-Doped Polyacetylene In Vacuum, T. Inoue, J. E. Osterholm, H. Yasuda, L. L. Levenson Dec 1980

Thermal Decomposition Kinetics Of Asf5-Doped Polyacetylene In Vacuum, T. Inoue, J. E. Osterholm, H. Yasuda, L. L. Levenson

Physics Faculty Research & Creative Works

Electrical conductivity measurements, mass spectra of desorbing species, and ESCA surface analysis are reported for AsF5-doped polyacetylene heated between 50 and 130°C in vacuum. All measurements indicate first-order decomposition kinetics with activation energies between 13 and 20 kcal mole-1. Decomposition leads to the desorption of AsF3 and F2. Metallic arsenic remains in the polyacetylene as a decomposition by-product.


Sound Absorption In N2-H2O Gas Mixtures At Elevated Temperatures, Roger W. Meredith Dec 1980

Sound Absorption In N2-H2O Gas Mixtures At Elevated Temperatures, Roger W. Meredith

Physics Theses & Dissertations

Sound absorption measurements were conducted in N2 -H2O gas mixtures at 297, 343, and 387 Kelvin to determine the location of the vibrational relaxation peak of nitrogen on the frequency/pressure, (f/P), axis as a function of humidity and temperature. At low humidities the best fit of the data is to a linear relationship between (f/P)max and humidity (h) yields a slope of 1 .84 X 104 Hz/ atm mole fraction at all three temperatures. The slope is the same as that reported by Zuckerwar and Griffin (2.00 X 104 Hz/atm mole fraction) but is …


22nd Rocky Mountain Conference On Analytical Chemistry Aug 1980

22nd Rocky Mountain Conference On Analytical Chemistry

Rocky Mountain Conference on Magnetic Resonance

Abstracts and meeting program from the 22nd 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, August 10-14, 1980.


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


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.


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 …


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 …


Hall-Coefficient And Resistivity At High Pressure In 1t-Tas2, Paul D. Hambourger, F. J. Disalvo Jan 1980

Hall-Coefficient And Resistivity At High Pressure In 1t-Tas2, Paul D. Hambourger, F. J. Disalvo

Physics Faculty Publications

No abstract provided.


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 …


Autooscillations And Nonlinear Anelasticity, Manfred Wuttig, Tetsuro Suzuki Jan 1980

Autooscillations And Nonlinear Anelasticity, Manfred Wuttig, Tetsuro Suzuki

Materials Science and Engineering Faculty Research & Creative Works

In conclusion it can be stated that a novel phenomenon, a mechanical auto oscillation, has been described theoretically and shown to exist experimentally. These auto oscillations occur when a nonlinear anelastic solid is forced into large amplitude oscillations in the vicinity of a martensitic transformation. They manifest themselves as a low frequency auto modulation of the a martensitic transformation. They manifest themselves as low frequency auto modulation of the forced vibration of such a solid. © 1980.


Injection-Locked Dye Laser Pumped By A Xenon-Lon Laser, E. R. Carney, D. W. Fahey, Laird D. Schearer Jan 1980

Injection-Locked Dye Laser Pumped By A Xenon-Lon Laser, E. R. Carney, D. W. Fahey, Laird D. Schearer

Physics Faculty Research & Creative Works

Injection locking of a dye laser is reported for a 4-minor ring-cavity dye User pumped by a xenon-ion laser. Both a He-Ne laser and tunable CW dye laser were used as the injection sources. Copyright © 1980 by The Institute of Electrical and Electronics Engineers, Inc.


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.


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.


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.


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.


Direct Relation Between Fresnel’S Interface Reflection Coefficients For The Parallel And Perpendicular Polarizations, R. M.A. Azzam Jul 1979

Direct Relation Between Fresnel’S Interface Reflection Coefficients For The Parallel And Perpendicular Polarizations, R. M.A. Azzam

Electrical Engineering Faculty Publications

We have found a significant relation, rp = rs (rs -cos2ϕ)/(1-rs cos2ϕ), between Fresnel’s interface complex-amplitude reflection coefficients rp and rs for the parallel (p) and perpendicular (s) polarizations at the same angle of incidence ϕ. This relation is universal in that it applies to reflection at all interfaces between homogeneous isotropic media collectively and, of course, throughout the electromagnetic spectrum. We investigate the properties of this function, rp = f (rs), and its inverse,rs = g (rp), as …


Relations Between Amplitude Reflectances And Phase Shifts Of The P And S Polarizations When Electromagnetic Radiation Strikes Interfaces Between Transparent Media, R. M.A. Azzam Jun 1979

Relations Between Amplitude Reflectances And Phase Shifts Of The P And S Polarizations When Electromagnetic Radiation Strikes Interfaces Between Transparent Media, R. M.A. Azzam

Electrical Engineering Faculty Publications

No abstract provided.


Transformation Of Fresnel’S Interface Reflection And Transmission Coefficients Between Normal And Oblique Incidence, R. M.A. Azzam Apr 1979

Transformation Of Fresnel’S Interface Reflection And Transmission Coefficients Between Normal And Oblique Incidence, R. M.A. Azzam

Electrical Engineering Faculty Publications

If w denotes an interface Fresnel reflection or transmission coefficient for s- or p-polarized light at an oblique angle of incidence ø, and z denotes the same coefficient at normal incidence, we find that w is an analytic function of z, w = ƒ(z), that depends on ø but not on the specific optical properties of the two media on both sides of the interface. All four functions that correspond to the four distinct Fresnel coefficients and their inverses are determined. We single out for detailed examination, as an example, the relationship between the reflection of s -polarized light at …


Reflection Of An Electromagnetic Plane Wave With 0 Or Π Phase Shift At The Surface Of An Absorbing Medium, R. M.A. Azzam Mar 1979

Reflection Of An Electromagnetic Plane Wave With 0 Or Π Phase Shift At The Surface Of An Absorbing Medium, R. M.A. Azzam

Electrical Engineering Faculty Publications

An electromagnetic plane wave incident obliquely from a transparent medium onto the surface of an absorbing medium can be reflected with 0 or π phase shift if (i) the wave is p (TM) polarized, and (ii) the complex relative dielectric function ε is such that 0 ≤|ε| 2/2Re(ε) ≤ 1. Furthermore, the locus of ε such that the reflection coefficient for the p polarization is real at the same angle of incidence, is a circle, and that of ε½ (the complex relative refractive index) is Bernoulli’s lemniscate.


The Modification And Use Of An Electron Paramagnetic Resonance Spectrometer For Data Collection At Liquid Nitrogen Temperature, Vernon Lee Baumberger Jan 1979

The Modification And Use Of An Electron Paramagnetic Resonance Spectrometer For Data Collection At Liquid Nitrogen Temperature, Vernon Lee Baumberger

Electronic Theses and Dissertations

The scope of this study includes the modification of an EPR spectrometer for acquisition of low temperature data. The modification involved adaptation of the system for use with a cylindrical cavity specifically designed for low temperature operation. This modification increased the capability of the present system for data collection at liquid nitrogen temperature and gave such greater stability than the rectangular cavity previously used. A comparison was made of signal to noise for the two cavities. This study showed a somewhat greater signal to noise ratio for the low temperature cylindrical cavity. Operation at low temperature also allowed the observation …