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Measurements Of Excited-State Population Ratios Of Atomic Hydrogen Produced By Charge-Exchange Neutralization Of Energetic Proton Beams, Robert H. Mcfarland, Archer H. Futch

Physics Faculty Research & Creative Works

Excited-state population ratios for atomic hydrogen have been measured for energetic hydrogen ions neutralized by charge exchange with a number of different metallic vapors and permanent gases. Electric field ionization techniques were used to determine excitation ratios. Detection of the energetic ions and neutrals was accomplished using partially depleted surface-barrier detectors. Counting, using phase-detection techniques in which an add-subtract scaler was phased to the signal, provided an improved signal-to-noise ratio. Two methods were used to provide desired targets. Metallic vapor and permanent-gas thin targets of the order of 10-5 mTorr cm were produced as chopped neutral beams, using conventional crossed-beam …

Ground-State Wave Function Of Shallow Donors In Uniaxially Stressed Silicon: Piezohyperfine Constants Determined By Electron-Nuclear Double Resonance, Edward B. (Boyd) Hale, Theodore G. Castner

Physics Faculty Research & Creative Works

Stress-induced changes in the ENDOR spectra of a shallow donor electron interacting with various Si29 nuclei neighboring the donor have been experimentally and theoretically investigated. For each of the three measured donors - As, P, and Sb - the compressional, uniaxial stress was applied along the [001] axis and its magnitude corresponded to strains up to 10-3. To describe the observed linear and quadratic shifts and splitting's of the lines in an ENDOR shell, we have defined a set of piezo hyperfine constants. One piezo hyperfine constant was measured for each axis-class shell; three independent piezo hyperfine constants were measured …

Shell Source Burning Stars With Highly Condensed Cores, S. Refsdal, A. Weigert

Department of Physics and Astronomy: Faculty Publications

Simple analytical relations are derived - similar to the homology relations for homogeneous stam - which describe the behaviour of shell source burning models with highly condensed cores. Many features which are known from evolutionary calculations (and partly &om observations) of such stars can be understood as coming essentially from the increase of the mass M₆ of the core.

Emission Of Auger Electrons Resulting From Symmetric Argon And Neon Ion-Atom Collisions, R. K. Cacak, Q. C. Kessel, M. Eugene Rudd

M. Eugene Rudd Publications

Cross sections for the emission of Auger electrons from excited atoms and ions produced in symmetric Ar⁺-Ar and Ne⁺-Ne collisions have been measured at ion energies from 50 to 300 keV. A simple model is proposed to explain the dependence of the cross section on the impact energy; the predicted results agree well with the experiment. Also, the argon x-ray data of Saris and Onderdelinden are compared with the model and with the results of this experiment.

Auger Electrons From Argon With Energies 150-210 Ev Produced By H+ And H2 Impacts, D. J. Volz, M. Eugene Rudd

M. Eugene Rudd Publications

Secondary electrons in the energy range 150-210 eV produced by 125-300-keV H⁺ and H₂⁺ impacts on argon gas are measured as a function of their energy and angle of emission. Discrete line spectra are due to Auger transitions from L₂ and L₃ vacancy states as well as satellite transitions from multivacancy states. The widths, energies, and branching ratios of the L₂ and L₃ vacancy states are presented. Widths of these states are appreciably greater than those obtained with electron impact excitation. This can be attributed to the recoil velocities of the target atom …

Experimental Evidence For The Mechanism Of Charge Transfer Into Continuum States, G. B. Crooks, M. Eugene Rudd

M. Eugene Rudd Publications

We have observed a prominent peak in the energy spectrum of electrons ejected in the forward direction from helium bombarded by protons ranging in energy from 100 to 300 keV. The peak occurs at an ejected-electron velocity equal to the velocity of the incident proton. The experimental results verify the existence of the mechanism of charge transfer into continuum states of the incident ion.

A Fundamental Investigation Of The Gas Phase Polymerization Of Styrene And Vinyl Type Monomers In A Low Power Inductively Coupled 4 Mhz Rf Plasma, L. F. Thompson

Doctoral Dissertations

"A study has been made on the plasma polymerization of styrene and vinyl type monomers in a cold, low power, inductively-coupled RF plasma. All vinyl type monomers yielded an insoluble, crosslinked film which was slightly colored. A kinetic study is reported for styrene. The effects of power level, bleed rate of monomer, pressure and reactor geometry on the rate of polymer formation are reported. A mechanism is postulated for plasma polymerization. It was found that the initiation step was the rate controlling step and that the reaction followed a cationic polymerization scheme. Both crosslinking and discoloration of the polymers occur …

A Quasi-Lattice Model Of Simple Liquids, Jesse Herbert Collins

Doctoral Dissertations

"A cellular model of simple liquids is proposed which eliminates the objectionable feature of long range order found in other cell models. The volume is divided into N identical spherically symmetric cells, each occupied by one molecule. The cell-center density distribution relative to an average given cell center forms a series of Gaussian peaks whose width is proportional to the square root of the distance from the given cell center. The number of cell centers and average radial distance represented by each of the peaks correspond to a face-centered cubic lattice. The molecular pair distribution function is determined for several …

Discrimination Of Signal And Noise Events On Seismic Recordings By Linear Threshold Estimation Theory, David Nuse Peacock

Doctoral Dissertations

"The object of this study is the investigation of a linear threshold element technique for identifying surface multiples on a single seismic trace. Traces of seismic events were generated which contained primaries, surface multiples, and various levels of Gaussian random noise. Since it was necessary to separate the events as much as possible, the traces were subjected to pulse-compression deconvolution processing prior to LTE analysis. Mean frequency, peak frequency, amplitude spectrum variance, periodicity, and polarity were employed as pattern parameters. A set of weights was found that would maximize the moment of inertia of the S line distribution of the …

The Electrochemical Oxidation Of 1-Pentyne On Platinum And Gold, Michael Jensen Danielson

Doctoral Dissertations

"The anodic oxidation of 1-pentyne was studied at 70°C on Pt and Au electrodes in solutions of H₂SO₄, K₂SO₄, K₂CO₃, and KOH. Pt was studied in a pH range of 0.35 - 12.7 and Au in a range of 10.9 - 12.7. Reaction rates were measured as a function of potential, pH, temperature, and 1-pentyne partial pressure. The coulombic efficiencies for the oxidation to CO₂ were 77 percent in 1 N H₂SO₄ and 69 percent in 1 N KOH on Pt and 43 percent in 1 N KOH on Au. The kinetic parameters on Pt were [partial derivative]V/[partial derivative]log i …

Theory Of Shallow Donor Impurity Surface States, Vidal Emmanuel Godwin

Doctoral Dissertations

"A variational approach has been used to solve the effective-mass equation, when the impurity ion is located at a depth d from the surface of a semiconductor, where 0 < d < d_b and d_b represents the case when the impurity ion is in the bulk of the semiconductor. The ground state and the excited state having the largest electric dipole coupling to the ground state have been determined. We have plotted the energy dependence on the depth of the impurity ion from the surface of the semiconductor. The energy has also been calculated as a function of the orientation of the …

Investigation Into The Monotonic Magnetostriction And Magnetic Breakdown In Cadmium, James Milo Carter

Doctoral Dissertations

"Observations of the monotonic magnetostriction of cadmium at 4.2 K and in fields of 65 kilogauss have been made. The angular dependence of an extremal point (H_m) in the monotonic magnetostriction is found to follow inverse cosine behavior. The magnitude of H_m (27 kG) for fields parallel to [0001] is in fair agreement with the onset of γ_1/3 from the breakdown of the trifoliate orbit, γ. The range of observation of h_m coincides with the reported range of the trifoliate orbit. A "klink" in the monotonic magnetostriction is demonstrated. The "klink" field, H_k, …

The Possible Correlation Of Carcinogenic Activity With Electronic Structure Of Benz(A)Anthracene, Patricia Joan Blair

Masters Theses

"The electronic structure of benz(a)anthracene based on the sigma and pi electrons was predicted by the modified intermediate neglect of differential overlap (MINDO) molecular orbital method and compared with the pi electronic structure determined by the Pople method. The crystalline molecular structure was used for both methods. The Pople calculation was also done on the aromatic molecular structure and a combination structure which assumed the bond lengths of the crystal structure and the bond angles of the aromatic structure. Chemical properties predicted by the MINDO and POPLE electronic structures were compared; the MINDO results provided the best agreement with experimental …

Linear Regression Models Of Sound Velocity In The North Atlantic Ocean Below A Critical Depth, Richard Roland Kunkel

Doctoral Dissertations

"Sound velocity models currently in use by the U. S. Navy require difficult data sampling at great expense. This study is to investigate the feasibility of a sound velocity model dependent only upon position that would be valid for a selected, reasonably large, near homogeneous area of the ocean. The most important position parameters are latitude, longitude, and depth. To accomplish this objective a critical depth of 2500 meters was established for an 8° by 20° rectangle of the Sargasso Sea which lies within the North Atlantic Ocean. The critical depth is defined as the depth at which the characteristics …

Thermochemical Hydrogen-Deuterium Isotope Effects, Wayne C. Duer

Doctoral Dissertations

"The heats of solution at 25.0 ± 0. 1°C for each member of hydrogen-deuterium isotopic pairs (chloroform/chloroform-d, acetone/acetone-d₆, methanol/methanol-d₁, ethanol/ethanol-d₁, and water/heavy water) have been determined as a function of molality in a variety of solvents. The heats for most of the systems could be described as a linear function of average molality with an average deviation in fit of less than one per cent. Using these linear equations, heats of solution at infinite dilution were obtained by extrapolation to zero molality. The heats of solution at infinite dilution of the hydrogen containing compounds were subtracted from those of the …

An Experimental And Theoretical Study Of The Nucleation Of Water Vapor On Ions In Helium And Argon, Daniel R. White

Doctoral Dissertations

"The nucleation of water vapor on ions in atmospheres of helium and argon was studied using an expansion type cloud chamber. Separation of the positive and negative ions was achieved so that the nucleation could be studied as a function of both the sign of the ionic charge and the supersaturation. A semiphenominological theory was developed as an extension of the classical theory to include the effects of the ionic charge on the nucleation process. The theoretical model of the prenucleation embryo was assumed to possess an oriented dipole surface layer with the direction of orientation dependent on the sign …

Radiative Lifetime Of The A¹Π State And The Transition Moment Variation Of The Fourth Positive Band System Of Carbon Monoxide, Joseph George Chervenak

Doctoral Dissertations

"The lifetime of the A¹π state of carbon monoxide has been measured using a pulsed invertron excitation source and delayed coincidence measurement technique on the fourth positive system. Eighteen bands, originating from the upper states v' = 0 to 5, were examined at pressures between 500 and 50 microns, with no pressure dependence noted. The data were corrected for photon "pile up" and least-squares fitted to the sum of two exponentials. The transition moment was found to vary and was expanded about the r-centroid of the v' = 0 to v" = 0 transition. Oscillator strengths are calculated and compared …

A Coordinate Oriented Algorithm For The Traveling Salesman Problem, Joseph Sidney Greene

Doctoral Dissertations

"The traveling salesman problem may be stated as follows: "A salesman is required to visit each of n given cities once and only once, starting from any city and returning to the original place of departure. What route should be chosen in order to minimize the total distance traveled?" A new algorithm is developed which gives a good approximation to the solution for a large number of cities using reasonable computer time and which will converge to the exact solution if allowed to continue. This algorithm is a branch and bound technique which utilizes the distance between cities in its …

A Study Of Far Infrared Grid Filters, Harold Victor Romero

Doctoral Dissertations

"The diffraction theory for the transmission of electromagnetic fields through a grid in a dielectric is derived and experimentally checked in the visible wavelength region. In the far infrared, an approximate mathematical representation is found to describe the grids in dielectrics. The empirical equations in the far infrared are combined with the electrical circuit-transmission line analog for inductive grids. Detailed structure of the transmittance versus wave number curves are presented. Then the theory of multielement grid filters is derived and compared with experiment. The properties of the filters can be predicted from a knowledge of the characteristics of the individual …

Realistic Impulsive P Wave Source In An Infinite Elastic Medium, Joseph Hugo Hemmann

Doctoral Dissertations

"The generally assumed instantaneous impulsive pressure sources for an elastic P wave in an infinite medium lead to basic contradictions, a step function source yielding infinite displacements as the shear modulus goes to zero, and the total energy radiated by a delta function (or any derivative of the delta function) source being infinite. By noting that the character of the solution in the elastic region must match the acoustic case near the source, a realistic impulsive pressure source is postulated which has a finite time history. The elastic field produced by this source is then obtained in closed form. A …

Structures And Relationships Of Some Perovskite-Type Compounds, Christian Michel

Doctoral Dissertations

"A model for crystallographic transitions in perovskites is proposed. The model consists of regular octahedra sharing corners and topologically able to rotate without distortion around their three-fold axes. This model, with R3̄c symmetry (18e position) can be described in terms of a continuous rotation of angle, w, of octahedra from two ideal symmetry forms: the hexagonal close-packed and the cubic face-centered configurations. A parametric relation is derived between w and the rhombohedral cell angle, α, or the corresponding hexagonal axial ratio c/a . A wide range of atomic structures based on a framework of regular or slightly distorted octahedra sharing …

Substitution And Photolytic Rearrangements In Three-Member Ring Compounds, Joseph Terril Bohanon

Doctoral Dissertations

"An investigation into the substitution and photolytic rearrangements of 1,2,3-triphenylcyclopropenes was conducted. Triphenylcyclopropenyl t̲-butyl ether was found to undergo alkyl group exchange with refluxing methanol, ethanol, or 2-propanol to yield the corresponding 1,2,3-triphenylcyclopropenyl alkyl ether when a trace impurity of a 1,2,3-triphenylcyclopropenium halide is present to catalyse the reaction. This forms hydrogen halide with solvent. Upon standing for long periods of time, the 1,2,3-triphenylcyclopropenyl ethers were observed to partially rearrange to new products. A sample of 1,2,3-triphenylcyclopropenyl methyl ether was subjected to photolysis in hexane and yielded 3-methoxy-1,2-diphenylindene, 2,3- diphenylindenone, tolane, benzoic acid, 1,2,3-triphenylpropen-1-one and a polymer. Samples of 1,2,3-triphenylcyclopropene, …

The Surface Effects Of Alkali Halides In The Infrared, Vincent Joseph Llamas

Doctoral Dissertations

"The surface state extension of the shallow donor theory is reviewed. The surface state theory and its applications to F-centers of alkali halides is presented. Experimental infrared data show an absorption which seems to correspond with the ground state to first excited state transition. Surface state concentrations of F-centers as a function of depth into the crystal are given. The ratio of surface to bulk cross sections in KBr and experimental calculations of effective masses in various alkali halides are in excellent agreement with theory. The theoretical cross sections are derived from transition probabilities. However, lack of excited states, the …

Authigenic Analcite In The Golden Valley Formation Southwestern North Dakota, Marvin J. Furman

Theses and Dissertations

Authigenic analcite constitutes up to about 60 percent of a massive, arksosic sandstone exposed on major buttes in the North Dakota Badlands. The analcite constitutes up to about 80 percent of a thin analcimolite bed at the top of the arkose unit. The analcite occurs as spherulites in the interstices of the arkose and as a cement in the analcimolite. Three types of spherulites are recognized: (1) spherulites with an internal radial structure; (2) spherulites with a massive center and a peripheral radial structure; and (3) spherulites lacking an internal radial structure or having a poorly-defined internal structure. The spherulites …

Groundwater Flow In Part Of The Little Missouri River Basin, North Dakota, Thomas M. Hamilton

Theses and Dissertations

The Little Missouri valley in western North Dakota is deeply incised into slightly permeable Mesozoic and Cenozoic sediments. An evaluation of the groundwater flow in part of this valley was 'based on the present groundwater flow-system models. Abrupt changes in the hydrochemical facies have been explained relative to a continuous flow system.

The Little Missouri valley ls the discharge area of a regional groundwater flow system; it affects the potential distribution of the flow system for a minimum of 1.000 feet below the valley floor. The discharge area is approximately the same width as the valley floor and has a …

Rates Of Hillslope Lowering In The Badlands Of North Dakota, John R. Tinker Jr.

Theses and Dissertations

Measurements in a small drainage basin in the Little Missouri Badlands of western North Dakota indicate an average rate of hillslope lowering by slopewash of 0.41 inch per year on the west-facing hillslopes underlain by the Sentinel Butte Formation, 0.14 inch per year on the southwest-facing hillslopes underlain by the Tongue River Formation, and 0.11 inch per year on the northeast-facing hillslopes underlain by the Tongue River Formation. Soil creep occurs mainly on the Tongue River Formation and is mostly restricted to the northeast-facing hillslopes where the average rate of soil creep parallel to the hillslope surface is 0.23 inch …

The Design And Construction Of A Constant Acceleration Drive System For Mössbauer Experiments, James Donald Russell

University of the Pacific Theses and Dissertations

An excited nucleus may undergo a transition to its ground state by the emission of a gamma ray. The nucleus, if free to do so, will recoil and take some of the transition energy as recoil energy leaving less energy for the emitted gamma ray. This gamma ray does not have enough energy to excite a similar nucleus and will, therefore, not by resonantly absorbed due to the fact that the natural linewidth of the gamma ray is so much smaller than the energy taken by the emitting atom and the similar energy needed by the absorbing atom.

In 1958 …

The Preparation Of Coordination Compounds Of Rhodium Iii And Some Substituted Pyridines, Campbell John Mcrobbie

University of the Pacific Theses and Dissertations

The purpose of this study, then, is to prepare and characterize the complexes produced by the reaction of these ligards with rhodium III chloride. Of particular interest will be the mode of bonding of the ligand to the metal ion. For the first two groups, the potential exists for bonding to the metal from different parts of the ligand molecule. Bridging and chelation are also possibilities. Examination of the infrared spectrum of each complex should produce information as to the position of bonding. For one complex of the aminopyridines an N.M.R. spectrum will be examined.

Dimethyl Sulfoxide Oxydation Of Hydroxy-Steroids And Studies On The Oxidation Of The 5’–Hydroxy Group Of Nucleosides, Carmen V. Zenarosa

Dissertations

Introduction

In our earlier work we demonstrated the usefulness of the acidcatalyzed reaction between N-(p -tolyl)diphenylketenimine (21) and dimethyl sulfoxide (DMSO) for the oxidation of secondary alcohols. This was exemplified by the oxidation of 2',3'-O-isopropylideneadenosine and other secondary alcohols.¹ We have now extended this procedure to the oxidation of hydroxy-steroids.

Alkynylamines or ynamines can be written in two resonance forms: R-C≡C-N R'₂ and R-C=C=NR'₂. Because of the close similarity between the latter structure and the structure of a ketenimine (R₂C=C=N-R') and the ability of sulfoxide-ketenimine to effect the oxidation of secondary alcohols, we …

Problems And Management Of Water Quality In Hillsborough Bay, Fl, Federal Water Pollution Control Administration

Reports

Full scale filed operations began on June 8, 1967. Since that time, a pattern of pollution, water quality degradation and a complex ecological system has been defined.