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Articles 89401 - 89430 of 91704

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Simultaneous Knudsen- And Torsion- Effusion Measurements Of The Vapor Pressures Of Tetraphenyltin And Hexaphenylditin, Dale Keiser Dec 1969

Simultaneous Knudsen- And Torsion- Effusion Measurements Of The Vapor Pressures Of Tetraphenyltin And Hexaphenylditin, Dale Keiser

Masters Theses

No abstract provided.


A Study Of Some Matrix Elements For The Four-Pion Decay Mode Of Neutral Bosons, George Victor Weller Dec 1969

A Study Of Some Matrix Elements For The Four-Pion Decay Mode Of Neutral Bosons, George Victor Weller

Masters Theses

No abstract provided.


Entropy Of The Mixed State Of Some Low-Κ Type-Ii Superconductors, Don Carlos Hopkins, R. R. Rice, J. M. Carter, J. D. Hayes Dec 1969

Entropy Of The Mixed State Of Some Low-Κ Type-Ii Superconductors, Don Carlos Hopkins, R. R. Rice, J. M. Carter, J. D. Hayes

Physics Faculty Research & Creative Works

The entropy of the mixed state of type-II superconductors with low κ(∼1) is studied for the alloys Pb0.96Tl0.04 and In0.88Sn0.12. The current theories are reviewed for approximations valid near Hc1 and near Hc2. The experiments show for the most reversible sample (Pb0.96Tl0.04) that (SB)T of the mixed state depends only on temperature, and that (ST)B increases linearly with B from its value for the superconducting state until it drops discontinuously to its normal state value at Hc2. There is no abrupt increase in the specific …


A Heavy-Ion Energy Loss Spectrometer, John T. Park, F. D. Schowengerdt Dec 1969

A Heavy-Ion Energy Loss Spectrometer, John T. Park, F. D. Schowengerdt

Physics Faculty Research & Creative Works

A high-resolution system for the measurement of the energy loss spectra of 20-250 keV heavy ions incident on gas targets is described. The high resolution is obtained by decelerating the ion beam to a low, well-defined energy before performing the energy analysis. The energy loss spectrum is determined by changing the accelerator energy to compensate for energy lost in collisions with the gas atoms. The system is arranged so that normal fluctuations in the accelerator's power supply do not affect the energy resolution. The resolving power of the system is 2.5x104. The primary proton beam has a detected WHM of …


Some New Approaches To Shallow Impurity States, Wayne E. Tefft, Robert John Bell, Harold V. Romero Dec 1969

Some New Approaches To Shallow Impurity States, Wayne E. Tefft, Robert John Bell, Harold V. Romero

Physics Faculty Research & Creative Works

A variational calculation of shallow surface impurity states including image-charge and anisotropic mass effects was performed using two different sets of orthogonal functions. The first set was obtained by varying the Bohr radius in the hydrogenic functions, separately for each state. In the second set the Bohr radius was allowed to become anisotropic, and the elements were separately treated as variational parameters. In each case it was shown that with certain restrictions on the variational parameters the set remained complete and orthogonal. General expressions for the energy eigenvalues for both the bulk and surface problem obtained from the first set …


Charge-Transfer Cross Sections For Negative Ions On Atomic And Molecular Targets, W. (William) R. Snow, R. D. Rundel, R. Geballe Dec 1969

Charge-Transfer Cross Sections For Negative Ions On Atomic And Molecular Targets, W. (William) R. Snow, R. D. Rundel, R. Geballe

Physics Faculty Research & Creative Works

Charge-transfer cross sections for H- on O, O2, and NO2; O- on H, O, H2, O2, and NO2; and C- on H and O have been measured over an energy range of 0.5 to 4 keV using a modulated crossed-beam apparatus. The experimental cross sections are compared with theories of resonant and non-resonant charge transfer based on a two-state approximation. For the reactions H-+O O-+H, the cross sections are found to be consistent with detailed balancing. The effect of electron detachment on charge-transfer …


Heavy-Particle Energy-Loss Spectrometry: Inelastic Cross Sections For Protons Incident Upon Helium, John T. Park, F. D. Schowengerdt Dec 1969

Heavy-Particle Energy-Loss Spectrometry: Inelastic Cross Sections For Protons Incident Upon Helium, John T. Park, F. D. Schowengerdt

Physics Faculty Research & Creative Works

A method is described whereby absolute cross sections are obtained from inelastic energy-loss spectra induced by ions incident upon gaseous targets at energies of 25-125 keV. Inelastic energy-loss spectra of helium for proton impact are presented. Apparent differential cross sections and absolute total cross sections are obtained from the spectra. Total cross sections for the sum of the 1S1→2S1 and 1S1→2P1 excitations are reported, along with estimates of the relative contributions of each. Total ionization cross sections, total cross sections for inelastic scattering, apparent energy distributions of ejected electrons, and partial ionic stopping powers are also reported. The excitation cross …


Transpiration Measurements Of The Decomposition Pressures Of Barium Hexafluorosilicate, Kemal Cankaya Dec 1969

Transpiration Measurements Of The Decomposition Pressures Of Barium Hexafluorosilicate, Kemal Cankaya

Masters Theses

No abstract provided.


Preparation And Lead Tetraacetate Oxidation Of Aldehydic Hydrazones, Alan J. Quarfoot Dec 1969

Preparation And Lead Tetraacetate Oxidation Of Aldehydic Hydrazones, Alan J. Quarfoot

Masters Theses

No abstract provided.


The Isoelectronic Principle And The Accuracy Of Binding Energies In The Hückel Method, Jerry Goodisman Nov 1969

The Isoelectronic Principle And The Accuracy Of Binding Energies In The Hückel Method, Jerry Goodisman

Chemistry - All Scholarship

In the Hükkel and other methods, binding energies are calculated by subtracting the sum of orbital electronic energies for the molecule from the sum of orbital electronic energies for the separated atoms, and not considering the internuclear repulsion. Since this last may be several orders of magnitude greater than the binding energy, reasonable results could not be obtained without an approximate cancellation with another neglected term. It is shown that such a cancellation is a consequence of the isoelectronic principle (invariance of binding energy to change in atomic number of constituent atom). Numerical examples are given.


Vibrational Excitation By Electron Impact Near Threshold In H2, D2, N2, And Co, Paul Burrow, G.J. Schulz Nov 1969

Vibrational Excitation By Electron Impact Near Threshold In H2, D2, N2, And Co, Paul Burrow, G.J. Schulz

Paul Burrow Publications

The trapped-electron method is applied to the measurement of the slopes of the vibrational cross sections near their respective thresholds. Absolute values are obtained by normalization to positive-ion cross sections. The values obtained in H2 are 43 for v=1, 0.72, for v=2, 0.04, for v=3, and 0.003, for v=4, in units of 10-18 cm2/eV. The values for N2 are 2.5 for v=1 and about 0.02 for v=2, whereas, the values for CO are much larger, i.e., 120 for v=1 and 2.4 for v=2. Various corrections that are …


Interpretation Of A Unified Theory Of Gravitation And Symmetry Breaking, David Peak, A Inomata Nov 1969

Interpretation Of A Unified Theory Of Gravitation And Symmetry Breaking, David Peak, A Inomata

All Physics Faculty Publications

The formalism of Moen and Moffat is interpreted as a Yang-Mills theory set in a space-time generally endowed with curvature and torsion.


Manipulation Of Data Structure In A Numerical Analysis Problem Solving Systems, Lawrence R. Symes Nov 1969

Manipulation Of Data Structure In A Numerical Analysis Problem Solving Systems, Lawrence R. Symes

Department of Computer Science Technical Reports

No abstract provided.


A Note On The Free Distance Of A Convolutional Code, Alexander Miczo Oct 1969

A Note On The Free Distance Of A Convolutional Code, Alexander Miczo

Electrical Engineering and Computer Science - Technical Reports

A counterexample to a conjecture on the number of constraint lengths required to achieve the free distance of a rate l/n systematic convolutional code is presented.


Virus Movement In Groundwater Systems, William A. Drewry Sep 1969

Virus Movement In Groundwater Systems, William A. Drewry

Arkansas Water Resources Center Technical Reports

The purpose of this study is to investigate the extent to which soil acts as an agent in the transmission of waterborne viruses. Since many waterborne outbreaks of viral diseases have involved small wellwater supplies contaminated by effluents from subsurface wastewater disposal systems, there is a great need for such information. Results of this study show that virus adsorption by soils is greatly affected by the pH, ionic strength, and soil-water ratio of the soil-water system and various soil properties. Also, it is shown that one cannot predict the relative virus adsorbing ability of a particular soil based on the …


11th Annual Rocky Mountain Spectroscopy Conference Aug 1969

11th Annual Rocky Mountain Spectroscopy Conference

Rocky Mountain Conference on Magnetic Resonance

Program and abstracts from the 11th 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 4-5, 1969.


Sediments Of Biscayne Bay - Distribution And Depositional History, Harold R. Wanless Aug 1969

Sediments Of Biscayne Bay - Distribution And Depositional History, Harold R. Wanless

RSMAS Technical Reports

WANLESS, HAROLD R. (M.S., Marine Geology)

Sediments of Biscayne Bay - Distribution and Depositional History. (September 1967) Abstract of Master's Thesis at the University of Miami. Thesis supervised by Professor A. Conrad Neumann.

Three shallow elongate bays, Biscayne Bay, Card Sound and Barnes Sound trend south from Miami along the southeast Florida coast. Hand probing and coring through Recent sedimentary sequences within and bordering these bays has established the general character of the underlying bedrock topography, has revealed the general features of the sediment bodies and the spatial relations of the sediment types and has given insight into the …


Homogenous Catalytic Hydrogenation Of Organic Compounds Using Rhodium-Triarylphosphine Complexes, Jack Lee Parsons Aug 1969

Homogenous Catalytic Hydrogenation Of Organic Compounds Using Rhodium-Triarylphosphine Complexes, Jack Lee Parsons

Dissertations

Introduction

The purpose of this research was to study the homogeneous catalytic hydrogenation of α,β-unsaturated organic compounds containing a wide variety of reducible functional groups. The catalysts to be used were rhodium complexes of triarylphosphines. It was also desired to develop these catalytic systems into practical synthetic methods for the reduction of unsaturated compounds.


Nmr Determination Of The Conduction-Electron Hyperfine Interaction In Crystalline Cdo, David C. Look Aug 1969

Nmr Determination Of The Conduction-Electron Hyperfine Interaction In Crystalline Cdo, David C. Look

Physics Faculty Publications

Measurements of the Cd113 nuclear-spin-lattice relaxation time T1 and Hall effect in crystalline CdO, a degenerate semiconductor, have yielded the contact hyperfine strength of the conduction electrons at the nuclei. The product T1T=168 sec °K, independent of temperature T and frequency ν for T=1.4,4.2, and 77-350 °K, and for ν=2-10 MHz. Taking the carrier concentration N=2.6×1019 cm-3 independent of temperature to within 3% at 4.2, 77, and 300°K, and using an effective electron mass me*=0.2me, we calculate an averaged electron probability density at the nucleus, 〈|φF(0)|2 …


The Elastic Scattering Of 1.33 Mev Gamma Rays From Tin, J. Edward Terdal Aug 1969

The Elastic Scattering Of 1.33 Mev Gamma Rays From Tin, J. Edward Terdal

Masters Theses

No abstract provided.


The Wittig Reaction Of Stabalized Phosphonium Ylids With Derivatives Of D-Ribose, George Robert Wellman Aug 1969

The Wittig Reaction Of Stabalized Phosphonium Ylids With Derivatives Of D-Ribose, George Robert Wellman

Masters Theses

No abstract provided.


Data Retrieval In Mass Spectrometry By An Optical Coincidence System, Cynthia Helmintoller O'Donohue Aug 1969

Data Retrieval In Mass Spectrometry By An Optical Coincidence System, Cynthia Helmintoller O'Donohue

Master's Theses

The object of this work was to develop an information storage and retrieval system for use in mass spectroscopy. The information to be stored was the compound's name, the mass spectrum, and distinctive physical and chemical properties. It was desirable that the system be one that could be used in the mass spectral laboratory. At the time this project was initiated, no system for mass spectroscopy had been developed with the characteristics of simplicity, rapid retrieval, and practicality of use in the laboratory without elaborate and space consuming equipment. Thus, a system was needed to aid the laboratory personnel in …


A Kinetic Study Of The Oxidation Of The 2, 3, And 4 Pyridine Aldehydes By Cobalt (Iii) Perchlorate In Aqueous Solution., Ronald Barry Giuntoli Aug 1969

A Kinetic Study Of The Oxidation Of The 2, 3, And 4 Pyridine Aldehydes By Cobalt (Iii) Perchlorate In Aqueous Solution., Ronald Barry Giuntoli

All Master's Theses

Cobalt(III) perchlorate has been shown to be a powerful oxidizing agent and kinetic investigations of the mechanism of oxidation of many organic compounds including organic acids have been performed.


On The Theory Of Quaternions, Earle David Smith Aug 1969

On The Theory Of Quaternions, Earle David Smith

All Master's Theses

Ordered triplets serve to describe space geometrically just as ordered pairs serve to describe the plane. A multiplication can be defined on pairs consistent with the complex numbers. However, as this paper will show, one cannot define a multiplication on triplets which is consistent with the complex numbers.


A Translation Grammar For Algol 68, Victor B. Schneider Aug 1969

A Translation Grammar For Algol 68, Victor B. Schneider

Department of Computer Science Technical Reports

No abstract provided.


A Thermodynamic Approach To The Study Of Phase Equilibria In The Sodium-Potassium Alloy System I. The Phase Diagram For Nak At Atmospheric Pressure ; Ii. High Pressure Phase Studies, Donald Ray Anderson Aug 1969

A Thermodynamic Approach To The Study Of Phase Equilibria In The Sodium-Potassium Alloy System I. The Phase Diagram For Nak At Atmospheric Pressure ; Ii. High Pressure Phase Studies, Donald Ray Anderson

Theses and Dissertations

Ultra-pure reagents, platinum resistance thermometry and modern inert atmosphere glove box facilities have made possible a detailed examination of the NaK system at atmospheric pressure. A thermoanalytical study of solid-liquid phase equilibria in the NaK alloy system was conducted in the tetrahedral press to 55 kbars to investigate possible intermediate compound formation and shifting of the invariant points at various pressures. An expected shift in the eutectic composition to lower potassium content with an increase in the halt temperature on increasing pressure was confirmed. A merging of the meritectic and eutectic points at 343 ±2°K and 37 ±3 kbars occurred …


Thermodynamics Of Proton Dissociation And Metal Ion Complexation In Aqueous Solution. I, Cation Binding With Cyclic Polyethers: Significance In Ion Transport Processes. Ii, Proton Dissociation From Adenosine, Several Monosaccharides And Related Compounds. Iii, Proton Dissociation From Several Pyrimidines And Their Nucleosides At 10, 25 And 40°, Joseph Howard Ryttling Aug 1969

Thermodynamics Of Proton Dissociation And Metal Ion Complexation In Aqueous Solution. I, Cation Binding With Cyclic Polyethers: Significance In Ion Transport Processes. Ii, Proton Dissociation From Adenosine, Several Monosaccharides And Related Compounds. Iii, Proton Dissociation From Several Pyrimidines And Their Nucleosides At 10, 25 And 40°, Joseph Howard Ryttling

Theses and Dissertations

The log K, ΔH° and ΔS° values for the interaction of several metal ions with the two isomers of the cyclic polyether, 2,5,8,15,-18,21 hexaoxatricyclo[20.4.0.0^9,14]hexacosane are reported. The stability order found for alkali metal ion interaction with either isomer is identical to the order of ion permeability through reconstituted biological membranes for structurally related antibiotics. The size of the metal ion is critical in determining the extent of interaction. A calorimetric titration study of proton ionization from several monosaccharides and derivatives, pyrimidine bases and their nucleosides, adenosine and its derivatives, and cycloheptaamylose is described. The heats of reaction obtained in this …


The Catalytic Hydrogenation Of Benzodiazines.|Ni.|Pphthlazine.|Nii.|Pquinazoline, Danny Lee Elder Aug 1969

The Catalytic Hydrogenation Of Benzodiazines.|Ni.|Pphthlazine.|Nii.|Pquinazoline, Danny Lee Elder

Theses and Dissertations

Quinazoline and phthalazine were hydrogenated at low pressure and temperature (60 psi, room temperature) and high pressure and temperature (2000 psi, 100°C, 150°C} in neutral and acidic solvents over 5% Pd/C, 5% Ru/C, 5% Rh/Al2O3 , 5% Rh/C, and 5% Pt/C. Chromatographic methods for determining the qualitative and quantitative composition of hydrogenation mixtures were developed. The compositions of quinazoline and phthalazine-hydrogenation mixtures were determined. Eight phthalazine-hydrogenation products were detected and isolated: (1) 1,2-dihydrophthalazine, (2) 1,2,3,4-tetrahydrophthalazine, (3) a,a'-diamino-o-xylene, (4) o-methylbenzylamine, (5) 1,3-dihydroisoindole, (6) o-xylene, (7 and 8) cis- and trans- 1,2-dimethylcyclohexane. These products were identified by isolating them from reaction mixtures …


Generalized Threshold Decoding Of Convolutional Codes, Luther D. Rudolph Jul 1969

Generalized Threshold Decoding Of Convolutional Codes, Luther D. Rudolph

Electrical Engineering and Computer Science - Technical Reports

It is shown that any rate l/b systematic convolutional code over GF(p) can be decoded up to its minimum distance with respect to the decoding constraint length by a one-step threshold decoder. It is further shown that this decoding method can be generalized in a natural way to allow “decoding” of a received sequence in its unquantized analog form.


New Life For Prairie Lakes, Clyde Brashier, T. W. Edminster Jun 1969

New Life For Prairie Lakes, Clyde Brashier, T. W. Edminster

2019: Dr. Clyde Brashier

No abstract provided.