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High-Field Magnetoresistance Of Ordered Beta Brass , David J. Sellmyer, J. Ahn, J.-P. Jan Sep 1967

High-Field Magnetoresistance Of Ordered Beta Brass , David J. Sellmyer, J. Ahn, J.-P. Jan

David Sellmyer Publications

The magnetoresistance of several single-crystal specimens of ordered β-brass has been investigated in fields up to 150 kG. The purity of the samples is sufficiently high (ρ295/ρ4.2≃400) that the high-field condition is satisfied. The results indicate that ordered β-brass is an uncompensated metal and that its Fermi surface is multiply connected. Strong open orbits were observed when the field was in {110} or {100} planes, and this behavior is compatible with the Fermi-surface model predicted by augmented-plane-wave and Green's-function energy-band calculations. Evidence for the existence of higher-order open orbits and two-dimensional regions of open orbits is …

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The Kinetics Of Phase Transitions In Solid Cyclohexanol And Related Plastic Crystals., William Thomas Griffith Aug 1967

The Kinetics Of Phase Transitions In Solid Cyclohexanol And Related Plastic Crystals., William Thomas Griffith

Physics & Astronomy ETDs

The phase relations and the kinetics of phase transitions in the solid -forms of cyclohexanol, cyclohexanone, chlorocyclohexane, bromocyclohexane, and cyclopentanol have been investigated. Cyclohexanol has been studied the most thoroughly; the other compounds have been considered largely for purposes of comparison with cyclohexanol. The primary methods of investigation have been the measurement of dielectric properties and visual observations. The transitions in cyclohexanol have also been followed photographically in order to measure the growth velocities of the phase interfaces.

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Room-Temperature Second-Order Raman Spectra Of Csc1, Csbr, And Csi, A. M. Karo, John R. Hardy Aug 1967

Room-Temperature Second-Order Raman Spectra Of Csc1, Csbr, And Csi, A. M. Karo, John R. Hardy

John R. Hardy Papers

The room-temperature Raman spectra of CsC1, CsBr, and CsI have been computed from a simple, combined density-of-states approximation. Calculations have been made for four different model potential functions and compared with experiment in the cases of CsBr and CsI. In this way it is found that one of the variations, called the DD(-) model, is the most satisfactory. The agreement with the observed spectra is surprisingly close when one considers that no allowance has been made for variations in the elements of the Raman polarizability tensor.

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9th Annual Meeting Rocky Mountain Spectroscopy Conference Aug 1967

9th Annual Meeting Rocky Mountain Spectroscopy Conference

Rocky Mountain Conference on Magnetic Resonance

Program and abstracts from the 9th annual meeting of the Rocky Mountain Spectroscopy Conference, sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Denver, Colorado, August 7-8, 1967.

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Measurement Of Ultrasonic Absorption In Liquids By A Thermal Method, Ronald J. Tanis Aug 1967

Measurement Of Ultrasonic Absorption In Liquids By A Thermal Method, Ronald J. Tanis

Masters Theses

No abstract provided.

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Noise In Cadmium Sulfide & Cadmium Selenide Photoconductive Cells, Edward Foster Aug 1967

Noise In Cadmium Sulfide & Cadmium Selenide Photoconductive Cells, Edward Foster

Masters Theses & Specialist Projects

The primary object of this investigation is to design a system, including equipment and procedures, that can be used to evaluate the noise characteristics of photoconductive cells. The data once collected must be in a comprehensive and useful form. The secondary object is to use this system to evaluate a large number of cells of various types and to compare their noise profiles in a manner such that definite conclusions can be drawn concerning the absolute noise levels and profiles generated by the various cell types and the relations that may exist between the cells' noise output and the way …

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An Investigation Of The Refractive Index Of Selected Liquids In The Ultraviolet, Robert Bruce Eaton Aug 1967

An Investigation Of The Refractive Index Of Selected Liquids In The Ultraviolet, Robert Bruce Eaton

Masters Theses

No abstract provided.

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A Study Of The Backscatter Of Light From A Single Water Droplet, Theodore Stauffer Fahlen Aug 1967

A Study Of The Backscatter Of Light From A Single Water Droplet, Theodore Stauffer Fahlen

Physics & Astronomy ETDs

The backscattered light from a single water drop is studied theoretically and experimentally for drop diameters of about one millimeter. G. Mie gave the exact mathematical solution to the problem of an infinite, plane, monochromatic, electromagnetic wave scattered from a perfect sphere of any radius and index of refraction in 1908. The results of this theory are applied to drops of size parameter (defined as the ratio of the drop circumference to the wavelength of the incident light) near 3000; this corresponds to a drop diameter of about one millimeter. Theoretically, it is shown that the backscattered light originates from …

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Fe1+ And Fe2+ Hyperfine Fields In Mgo And Cao, J. Chappert, Richard B. Frankel, N. A. Blum Jul 1967

Fe1+ And Fe2+ Hyperfine Fields In Mgo And Cao, J. Chappert, Richard B. Frankel, N. A. Blum

Physics

Hyperfine interactions have been measured for Fe1+ and Fe2+ in MgO and CaO. The core polarization fields per spin moment are −127 kOeμB for both Fe1+ and Fe2+.

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Evaluation Of The Dispersion Relations Of Photoproduction, Paul Finkler Jul 1967

Evaluation Of The Dispersion Relations Of Photoproduction, Paul Finkler

Paul Finkler Papers

A modification of the Omnes method is used to solve the singular integral equations for the 3-3 partialwave amplitudes of photoproduction. The effects of multipion production are assumed to be negligible. The method requires a knowledge of the phase at all energies. Consequently, it is necessary to treat the corresponding pion-nucleon scattering problem to determine the eBect of the high-energy behavior of the phase on the solution for the scattering amplitude at low energies. The sharply resonant nature of the problen suggests an approximation in the form of solution, rather than in the Born terms, which leads to relatively simple …

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Anion Contributions To The Electrical Conductivity Of Alkali Chlorides, Robert Fuller, M.H. Reilly Jul 1967

Anion Contributions To The Electrical Conductivity Of Alkali Chlorides, Robert Fuller, M.H. Reilly

Robert G. Fuller Publications

The measured electrical conductivity of pure RbCl is separated into the usual anion and cation contributions with activation energies of 2.55 and 1.58 eV, respectively. By comparison with corresponding results for KC1 and NaCl it is found that the alkali-chloride anion and cation activation energies differ most for nearly equal anion and cation radii. We conclude from this anomalous trend that an extension of conventional theory is required.

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F Band In X- And Electron-Irradiated Caf2, David A. Patterson, Robert Fuller Jun 1967

F Band In X- And Electron-Irradiated Caf2, David A. Patterson, Robert Fuller

Robert G. Fuller Publications

This Letter reports an investigation using pulsed electron irradiation to determine if the low efficiency of F-band coloration in calcium fluoride is caused by the instability of the F center. No transient F centers were seen in times as short as 2 x 10-7 sec. It is concluded that the inherent efficiency of F-band coloration in CaF2 is small compared with similar processes in alkali halides and a possible reason for this is discussed.

Calcium fluoride has been extensively studied and is found to be more difficult to color than alkali halides and to have absorption …

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Integral Series Solution Of The Schrödinger Equation For The Helium Atom, W. Byers Brown, Ronald White Jun 1967

Integral Series Solution Of The Schrödinger Equation For The Helium Atom, W. Byers Brown, Ronald White

Center for Advanced Mineral and Metallurgical Processing (CAMP)

No abstract provided.

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Analytic Power-Series Solution Of The Schrödinger Equation For The Helium Atom, W. Byers Brown, Ronald White Jun 1967

Analytic Power-Series Solution Of The Schrödinger Equation For The Helium Atom, W. Byers Brown, Ronald White

Center for Advanced Mineral and Metallurgical Processing (CAMP)

No abstract provided.

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Mössbauer Evidence For A Spin-Compensated State In Dilute Fe-Cu Alloys, Richard B. Frankel, N. A. Blum, Brian B. Schwartz, Duk Joo Kim Jun 1967

Mössbauer Evidence For A Spin-Compensated State In Dilute Fe-Cu Alloys, Richard B. Frankel, N. A. Blum, Brian B. Schwartz, Duk Joo Kim

Physics

No abstract provided.

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Rocket Probe Measurement Of Electron Energy Spectra In The Earth's Radiation Belts, Donald Stuart Robb Jun 1967

Rocket Probe Measurement Of Electron Energy Spectra In The Earth's Radiation Belts, Donald Stuart Robb

Physics & Astronomy ETDs

No abstract provided.

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Inelastic Collisions Of The Second Kind Between Electrons And Excited Mercury Atoms, Paul Burrow Jun 1967

Inelastic Collisions Of The Second Kind Between Electrons And Excited Mercury Atoms, Paul Burrow

Paul Burrow Publications

The relative cross section for inelastic collisions of the second kind between electrons and mercury atoms in the excited 3P1 state was measured as a function of electron energy. Excited atoms were produced by absorption of the 2537 Å resonance line from a mercury arc. A low-energy beam of electrons was produced using the retarding potential difference method. Scattered electrons which gained kinetic energy were detected by passing them through a potential barrier which reflected unscattered electrons. The data are in good agreement with the cross section computed by applying detailed balancing to the known cross section for …

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Nuclear Quadrupole Relaxation., Derwin F. Brown Jun 1967

Nuclear Quadrupole Relaxation., Derwin F. Brown

Physics & Astronomy ETDs

A nucleus with an asymmetric charge distribution (an asymmetric arrangement of protons) exhibits a quadrupole moment which interacts with the gradient of the electric field of the surrounding electrons. The interaction energy is a function of the angle between the nuclear spin axis and the axis of the surrounding electric field. The nucleus processes about the electric field axis in quantized energy states. These quantized energy states correspond to a hyperfine splitting simi­lar to the hyperfine structure of the magnetic dipole-dipole interaction between the nucleus and the electrons. The application of an external electric field, oscillating at the processional frequency …

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An Introduction To The Fundamentals Of Radiation Transport Theory., William A. Proctor Jun 1967

An Introduction To The Fundamentals Of Radiation Transport Theory., William A. Proctor

Physics & Astronomy ETDs

I first became interested in radiation transport theory when, in August 1966, I was given primary responsibility for a large computer program which serves as a tool for solving high temperature, time dependent, radiation-hydrodynamics problems. Inquiries as to where to start learning about this subject invariably resulted in my being directed to the two books by Chandrasekhar (1957 and 1960) and the book by Kourganoff (1963). From the beginning of my study of these expositions, I found it rather curious that a theory which treated the radiation field as continuously distributed in space was formulated in a manner which appeared …

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Environmental Effects On The Resistivity Of Palladium-Silver Alloy Films In High Vacuum, Frank Snyder Jun 1967

Environmental Effects On The Resistivity Of Palladium-Silver Alloy Films In High Vacuum, Frank Snyder

Masters Theses & Specialist Projects

The reported usage of the palladium-silver alloy films as resistors in the electronics industry has been in encapsulated form. By mounting the resistor inside vacuum electron devices, there is the possibility of eliminating the encapsulation. A literature search has revealed no reported efforts of experiments with unencapsulated resistors and certainly no reports of the palladium-silver alloy resistor in vacuum tubes or other high vacuum environments. Therefore, the research reported in this thesis will concentrate on the environmental effects on resistivity of palladium-silver alloy films in high vacuum.

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Measurements Of Solar X-Ray Emission From The Ions Carbon Vi And Nitrogen Vii, Winifred Doyle Evans Jun 1967

Measurements Of Solar X-Ray Emission From The Ions Carbon Vi And Nitrogen Vii, Winifred Doyle Evans

Physics & Astronomy ETDs

Studies of the solar spectrum in the extreme ultraviolet and x-ray region have been possible since sounding rockets and satellites have been available to carry instruments above the earth's atmosphere. Progress was slow at first, but techniques have improved rapidly in recent years and a considerable body of experimental data has been accumulated since the first rocket flights in the late 1940’s.

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A Study Of Chromium-Doped High Lead Containing Silicate Glasses For Possible Laser Action, Mervet Maurice Saleh Jun 1967

A Study Of Chromium-Doped High Lead Containing Silicate Glasses For Possible Laser Action, Mervet Maurice Saleh

Archived Theses and Dissertations

No abstract provided.

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Rapid Calculation Of Electron Scattering Factors, Jerry Peacher, John G. Wills Jun 1967

Rapid Calculation Of Electron Scattering Factors, Jerry Peacher, John G. Wills

Physics Faculty Research & Creative Works

The phase amplitude method is used to reduce the radial Schrödinger equation to two separate differential equations, one for the phase and one for the amplitude. These functions are both smooth as opposed to the rapidly oscillating solution of the radial Schrödinger equation for electron energies in the kilovolt range. The partial-wave phase shifts were obtained rapidly by integrating the differential equations for the phase and amplitude numerically. Hartree-Fock and Thomas-Fermi-Dirac fields were used in the calculation. Results for argon and uranium are given in order to compare with previous results. It was found that the WKBJ approximation to the …

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Step-Wise Variation Of Spectrometer Quench Rates For Nuclear Quadrupole Resonance Measurements, Curtis M. Wise May 1967

Step-Wise Variation Of Spectrometer Quench Rates For Nuclear Quadrupole Resonance Measurements, Curtis M. Wise

Physics & Astronomy ETDs

In nuclear quadrupole resonance (NQR) it is desirable to better examine the magnitude of the resonance signals. This thesis describes the construction and testing of spectrometer control circuits which enable one to better examine a single resonance signal to the near exclusion of extraneous resonance side band responses and circuit noise in the NQR detection apparatus. Added to the basic spectrometer circuit is a step-wise varying quench rate control. For each adjustment of this control other control units are activated to keep the chosen NQR signal fixed in position and in magnitude within the spectrometer's span of detected radio frequencies. …

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Analysis Of Particle Counting Rate Variations Observed On Satellite Oso-B2, Esther Y. Ma May 1967

Analysis Of Particle Counting Rate Variations Observed On Satellite Oso-B2, Esther Y. Ma

Physics & Astronomy ETDs

The ommidirectional cosmic ray fluxes at an altitude of 300 miles and within ± 34 degrees latitude were studied using two Cerenkov counters and a scintillation counter aboard the 0S0-82 Satellite. The fluxes were found to depend strongly on the geomagnetic field with the trapped particles in the South Atlantic Radiation Anomaly being directional in some locations.

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²⁰⁷Pb (N, N') ²⁰⁷Pbm And ²⁰⁸Pb (N, 2n) ²⁰⁷Pbm Cross Sections, Edward Raymond Shunk May 1967

²⁰⁷Pb (N, N') ²⁰⁷Pbm And ²⁰⁸Pb (N, 2n) ²⁰⁷Pbm Cross Sections, Edward Raymond Shunk

Physics & Astronomy ETDs

The cross sections for the production of the 207Pbm state from 207Pb(n, n') and 208Pb(n, 2n) have been measured from the threshold through 14 MeV by observing the 1 .064 MeV gamma ray in the decay of 207Pbm (T ½ = 0.818 ± 0.004 sec) with a 3 in. x 3 in. NaI (T1) detector. Separated lead isotopes were irradiated for 4 sec and pneumatically transported to the detector. A 400-channel analyzer a used a time analyzer to record counts from neutron monitor during the irradiation and from the detector after the irradiation. These …

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Single And Multiple Pion Production In Π⁺N And Π‾P Interactions At 1.7 Gev/C, William J. Fickinger, D. K. Robinson May 1967

Single And Multiple Pion Production In Π⁺N And Π‾P Interactions At 1.7 Gev/C, William J. Fickinger, D. K. Robinson

Faculty Scholarship

Meson production in π-p and π+n interactions at 1.7 GeV/c has been studied in two bubble-chamber exposures. Combined results are presented with emphasis on single-pion production (4300 events) which is dominated by the formation of the ρ0 meson in peripheral interactions, and on double-pion production (1100 events) which shows strong formation of the ω meson. These data are compared with the predictions of particle-exchange models, including absorption, and the effects of competing channels are discussed. Evidence for a two-pion decay mode of the ω is examined quantitatively. Processes with higher meson multiplicities are described.

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Surface-Wave Phenomena At Liquid-Air Interfaces, Robert H. Dungan May 1967

Surface-Wave Phenomena At Liquid-Air Interfaces, Robert H. Dungan

Physics & Astronomy ETDs

The purpose of this investigation was to continue the study of surface wave phenomena initiated by Woodward and Bryant. [l], [2] Woodward, using an experimental arrangement similar to that shown in Fig. 3, observed that the intensity of light measured above, but parallel to, the reflected beam was a very sharp function of the incident beam angle at the critical angle. They also observed that the light intensity above the reflected beam decreased exponentially as the detector was moved away from the reflected beam in the plane of incidence. They reported characteristic lengths for the exponential decay constant of 9.6 …

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Observation Of Centrifugal Stretching In Sm152, D. Yeboah-Amankwah, L. Grodzins, Richard B. Frankel May 1967

Observation Of Centrifugal Stretching In Sm152, D. Yeboah-Amankwah, L. Grodzins, Richard B. Frankel

Physics

An isomer shift has been observed in the Mössbauer study of the 121.8-keV (2+→0+) transition in Sm152. A value of (Δ〈R2〉/〈R2〉)2-0=(10±3)×10-4 is deduced, based on isotope shift data for Sm152 and Sm154. This value disagrees with present theoretical prediction. In particular, the influence of the β band in Sm152 can only account for about 20% of the observed stretching.

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Epr Spectra Of Divalent Manganese In Halide Crystals, Veron Sarkis Sarkissian May 1967

Epr Spectra Of Divalent Manganese In Halide Crystals, Veron Sarkis Sarkissian

Archived Theses and Dissertations

No abstract provided.

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