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Stability Of Upgoing Auroral Ion Beams At 33 R(E) (Plasma, Magnetosphere, Wave-Particle Interactions), George Richard Ludlow

Doctoral Dissertations

Simultaneous upflowing hydrogen and oxygen beams of ionospheric origin are seen at altitudes near 3.3 R(,e) in the auroral zone by the DE-1 satellite. The beam observations indicate that, in addition to bulk acceleration, substantial heating in both hydrogen and oxygen has taken place either near or above the cold ionospheric source region. Velocity space distributions of the two ion species show hydrogen having a higher streaming velocity than oxygen, but also a smaller streaming energy. The region of velocity space between the two ion beam peaks has been filled in, with ions in the oxygen beam having been accelerated …

Structural Design Of Coal-Fueled Power Plant Ductwork, Stanley Pearce Rader

Doctoral Dissertations

"An absence of a comprehensive procedure for design of coal-fueled power plant ductwork currently exists in the publicly available literature. This dissertation presents such a procedure.

An overview of the ductwork design environment, including major components of the air and flue gas flow paths, design loads and temperatures, corrosion considerations, and physical configurations, is given. Design criteria for materials, corrosion inhibition, minimum plate thicknesses, temperature effects, allowable stresses and deflections, and vibrations are proposed. A detailed design procedure based on the allowable stress design philosophy is presented, and computer programs implementing the design procedure are provided. An alternate design procedure …

Amphiphilic Association Structures And Some Aspects Of Foam Stability, Jia-Hwa Fang

Doctoral Dissertations

"This investigation was performed in order to study two interesting and important problems in foams.

Foam separation was studied in the model system of water - sodium octylsulfonate - decanol. The efficiency of foam separation as a function of surfactant concentration and decanol content were measured. The results were related to the association structures of amphiphiles in aqueous systems.

Foam polymerization was conducted in the amphiphilic system containing water, polymerizable surfactant and oleyl alcohol. Liquid foams were produced in one three - phase region. The location and optical pattern of liquid crystals on the foam surface were observed by photomicroscope …

A Semantic Basis For Parallel Algorithm Design, Roger E. Eggen

Doctoral Dissertations

"As computing demands increase, emphasis is being placed on parallel architectures- To efficiently use parallel machines, software must be designed to take advantage of these machines. This research concentrates on an abstraction of algorithm design to permit the expression of parallel programs. The abstraction emphasizes thought about algorithms at a high level as opposed to algorithm implementation at a statement level. A model based on data flow allows algorithm expression using flow diagrams. The model specifies operating system requirements that support parallel programming at a module level. Paths are used to carry data between modules. Data enter modules through ports. …

A Study Of Electron-Ion And Ion-Ion Recombination In Atmospheric Gas Discharges, Michael Corbin Cornell

Doctoral Dissertations

"In separate experiments, the electron-ion recombination rate, Y_ei, has been measured in CO₂ and in mixtures of He, CO₂, and N₂; and the ion-ion recombination rate, Y_ii, has been measured in SF6 and in mixtures of SF₆ and CH₄. The rate constant was determined by analyzing the rising edge of the discharge current pulse. Measurements were made as functions of reduced electric field strength, gas pressure, and gas composition.

In the electron-ion recombination study, Y_ei in CO₂ and in mixtures containing N₂ and CO_{2 …}

Oxidation Kinetics Of Polycrystalline Srtio₃ And Lacro₃, Chi-Kung Jerry Yu

Doctoral Dissertations

"The oxidation kinetics of polycrystalline SrTiO₃ and LaCrO₃ were determined by measuring the time and temperature dependence of the weight and conductivity change of reduced samples. A region of fast diffusion followed by a reduced diffusion tail was observed in the TGA measurements. This observation can be interpreted as the initial diffusion along the boundaries and then spreading out into the lattice. The absence of the tail in the conductivity measurements is due to the high electron and hole mobility at the boundaries. The electrical conductivity and TGA results on Nb-doped LaCrO₃ show that at low oxygen …

Computer Applications In Quantitative Epr Spectroscopy Of Metalloproteins (Ferritin, Apoferritin, Iron), L Paul Rosenberg

Doctoral Dissertations

This dissertation examines the use of computers in quantitative EPR spectroscopy. The computers used ranged from hand held calculators to large main frame systems. Applications discussed are protein assay calculations, an EPR minicomputer interface and software system and the modification of an existing EPR simulation program to include corrections for strains in the g and A tensors. The modification permits more accurate linewidth simulation for lines with large M(,I) values. The computer interface and software allows for the collection of EPR spectra, which can then be stored, scaled, added, subtracted (for comparison) and double integrated. The program enhances weak signals …

Toward A Theory Of Positive Deviance, Druann Maria Heckert

Doctoral Dissertations

Although many studies have been conducted in regard to groups or individuals deemed to be negative deviants, there is a relative dearth of theoretical or empirical analysis of positive deviance. This dissertation attempts to theoretically analyze the concept of positive deviance.

The literature related to positive deviance was examined and categorized. Positive deviance was defined as behavior that people label (i.e., publicly evaluate) in a superior sense and behavior that usually results because the behavior departs from that which is considered normal or normative.

In addition, the previously postulated examples of positive deviance were utilized to form a typology of …

Hydrodynamic Characteristics And Coal Combustion Modeling Of A High Velocity Fluidized Bed (Solids Friction Factor, Two Phase Flow, Pressure Profile, Fast), Ronald Wayne Breault

Doctoral Dissertations

A Loop Fluidized Bed (LFB) based on the fast fluidization concept is a novel method for effective solid-gas contact and can play an important role in coal combustion. It can be operated under pressure making it eminently suited for the production of high temperature gas from coal for operating gas turbines for power generation. The LFB can operate over a wide range of gas flow rates and coal can be introduced at various points without excessive pressure drops. Further, it is possible to capture higher amounts of sulfur dioxide due to the use of fine dolomite or limestone particles. This …

Marital Power, Conflict And Violence (Negotiation Tactics, Egalitarian), Diane H. Coleman

Doctoral Dissertations

Conflict theory is used to analyze the relationship between marital power structure, the level of marital conflict and the rate of violence in a nationally representative sample of 2,143 American couples. Although previous authors suggest greater conflict in egalitarian relationships, other research demonstrates that there is less violence. Given the strong positive association between conflict and violence, a major question addressed in this research concerns this apparent contradiction.

Two explanations of this contradiction were empirically tested: (1) If the power structure is perceived as legitimate, the level of conflict and rate of violence may decrease, regardless of the actual power …

Risk And Uncertainty (Utility, Decision), Paul Snow

Doctoral Dissertations

The conventional theory of decision making under risk relies on axioms that reflect assumptions about people's subjective attitudes towards wealth. The assumptions are unverifiable, and the axioms are too restrictive. They forbid some decision rules that a plausibly rational decision maker ("DM") could find useful.

A new method, at once less restrictive and less dependent upon subjective assumptions, motivates expected utility techniques by assuming that a DM wishes to place an upper limit on the probability of ruin. All bounded-above, increasing functions defined over a suitable domain can serve as utility functions.

Now, DM can evaluate lotteries according to their …

Part I Preparation Of Novel Lactones And Their Precursors Derived From Methyl Salicylate Part Ii Nucleophilic Aromatic Substitution In A Dinitrosalicylic Lactone With Ring Opening And Elimination Via Meisenheimer Intermediates, Scott Daniel Rothenberger

Doctoral Dissertations

Part I. The synthesis, characterization, and physical properties of novel lactones and their precursors derived from methyl salicylate are described. The influence of substituents on the aromatic nucleus in affecting ring closure reactions was examined. Experimental results show that ring closure is enhanced when nitro groups are incorporated in the aromatic ring. Investigations were conducted in the preparation of compounds designed to exhibit ring-chain tautomerism.

Part II. Nucleophilic aromatic substitution reactions were carried out on 2-(2-hydroxyethoxy)-3,5-dinitrobenzoic acid, methyl ester and the corresponding seven-membered lactone. Nucleophiles chosen for study included iodide, several amines, hydroxide, methoxide, thiophenoxide, thiosulfate, sulfides, thiocyanate, cyanide, and …

Maine's New Juvenile Code: A Case Study In Juvenile Justice Reform, Dennis William Macdonald

Doctoral Dissertations

The history of juvenile justice in the United States is largely a history of failed reform efforts. The most significant of these efforts was the establishment of the juvenile court at the turn of the century and the idea of "socialized" juvenile justice on which it was based. Because the objective was rehabilitation rather than punishment, constitutional rights applicable in criminal justice proceedings were deemed unnecessary. In response to a wave of criticism of "socialized justice," the "post-Gault era" of juvenile justice reform emerged in the early 1960's. These reforms promised both justice and help to juveniles in trouble.

The …

Corrosion In Magnesium And A Magnesium Alloy (Az91c) As Modified By Ion Implantation, Sanay Akavipat

Doctoral Dissertations

"Magnesium and a magnesium alloy (AZ9 1C) have been ion implanted over a range of ion s energies (50 to 150 keV) and doses (1 x 10¹⁶ to 2 x 10¹⁷ ions/cm²) to modify the corrosion properties of the metals. The corrosion tests were done by anodic polarization in chloride -free and chloride containing aqueous solutions of a borated-boric acid with a pH of 9.3. Anodic polarization measurements showed that some implantations could greatly reduce the corrosion current densities at all impressed voltages and also increased slightly the pitting potential, which indicated the onset of the …

Dissolution Of Multi-Component Systems, Robin Ashley Murphy

Doctoral Dissertations

"The validity of ideal barrier layer diffusion kinetics was examined in the NaCl/KCl - glycerol and Al₂O₃-CaO-Al₂O₃-SiO₂/slag corrosion systems. Single crystals and dense polycrystalline plates of pure NaCl or KCl exhibit steady-state corrosion rates within 10%, of calculated theoretical values, while dense mixtures of the two salts corrode at rates higher than either pure material. The results are compared to the grooving phenomena of NaCl/KCl bicrystals.

Polycrystalline Al₂O₃ is shown to corrode at the same rate as single crystal sapphire at 1400°C in CaO-SiO₂-Al_{2 …}

Measurement Of The Far Infrared Optical Properties Of Steel, Aluminum, Evaporated Iron, And Teflon Fep, Raymond E. Paul

Doctoral Dissertations

"The optical properties of low-carbon shim steel, aluminum foil, and Teflon FEP have been measured in the 20 cm^-1 to 70 cm^-1 range. In particular, measurements of surface impedance for aluminum and low-carbon steel were used to calculate the imaginary part of the dielectric constant (&_{m, 2}). The resulting values of &_{m, 2} were of order 10⁶ for aluminum, and 10⁵ for steel. The imaginary part of the dielectric constant for metals is several times greater in magnitude than the real part in the frequency range of this experiment. Calculations of &_{m, …}

Optical Properties Of Natural Minerals In The Far-Infrared, Larry Lavern Long

Doctoral Dissertations

"The reflectivity of natural mineral powders were measured in the far infrared. The complex indices of refraction were then determined by Kramers-Kronig analysis or dispersive analysis. The samples were constructed by pressing the powdered sample into a 13 mm diameter pellet. A few of the samples that were measured were kaolin, illite, and montmorillonite, clay samples that could not be obtained in large single crystals. For calcite and gypsum crystals a comparison between the single crystal measurements and powder measurements was done to determine the effect of sample preparation on the measured spectra"-- Abstract, p. ii

Mass Transport Considerations In Electrometallurgical Reactions, Jose Rolando Sami Cuzmar

Doctoral Dissertations

"The research program described is divided into three segments. In the first part, the morphology and kinetic studies of Cd²⁺ removal from ZnSO₄ solutions using Zn dust as a reducing agent are presented. In the absence of impurities, the morphology of the Cd deposit shows the formation of two-dimensional or leaf-like dendrites capable of interlocking and forming agglomerates or balls. The size and strength of the agglomerates depend on the initial Cd²⁺ concentration to Zn metal surface area ratio, the rate of Cd ²⁺ removal, and the reactor geometry. The presence of additives, like Cu²⁺ and …

A Management Training Model For Engineers In Saudi Arabia, Majid Al-Kassabi

Doctoral Dissertations

“Great economic growth has occurred in Saudi Arabia in the last decade creating overwhelming demands for professionally trained people. The emerging Saudi professionals are mostly engineers who have been put in managerial positions without the benefit of managerial training.

Objectives of this research were 1) To identify the skills needed by engineers to become managers; 2) To identify problems and constraints inherent in management training programs; 3) To identify the impact of a model training program on the individual; and 4) The impact of a model training program on the firm.

A training program was implemented using an experimental group …

An Analysis Of Mill Sound Levels To Aid In The Control And Understanding Of The Grinding Process, Scott Douglas Morrison

Doctoral Dissertations

“An experimental study has been made to evaluate the relationships between grinding parameters and the directional sound levels emitted from the collision of the grinding media with the mill wall for a laboratory batch ball mill.

Discrete frequency and single frequency band sound pressure level measurements were performed to investigate the changes in sound levels with grind time. It was demonstrated that the reduction in sound levels with grind time observed for a narrow sized feed can be used to indicate optimum breakage rates, overall time-based particle size distribution, and ore character.

The relationships established with the discrete frequency and …

Numerical Simulation Of Mixing Processes In Two-Dimensional Channel Flows, Milan Karel Straka

Doctoral Dissertations

"Recently, considerable interest has arisen in the numerical simulation of laminar and turbulent transport phenomena. More knowledge in this field is needed to improve predictions of heat and mass transfer processes in a variety of technical fields.

In this work a new computationally efficient transport model is developed. It consists of partially parabolized time-dependent equations of motion, continuity, and concentration of nonconservative species. Pertinent equations are solved numerically for both laminar and turbulent flow.

Results of calculations of laminar flow in the entry region of a parallel-plate channel agree well with the work of other authors. For turbulent flows, the …

Kinetics And Reactor Design In The Pyrolysis Of Tar Sands, Charles Arthur Lechner

Doctoral Dissertations

"Data from the thermal decomposition of bitumen from Utah tar sands was obtained and analysed with both isothermal and non-isothermal chemical reaction models. The use of a power rate law to describe the complex kinetics of pyrolysis gave agreement with the experimental data that was approximate, but adequate for design purposes. The results indicated a reaction rate that was second order in bitumen content, with an activation energy of about 17 to 20 kcal/gmol.

Data for the boiling point distribution of the products was consistent with a change of mechanism from vaporization to pyrolysis as the samples are heated. Higher …

A Parallel Branch And Bound Algorithm For Integer Linear Programming Models, Rochelle L. Boehning

Doctoral Dissertations

"A parallel branch and bound algorithm is developed for use with MIMD computers to study the efficiency of parallel processors on general integer linear programming problems. The Haldi and IBM test problems and a System Design model are used in the implementation of the algorithm. Initially the algorithm solves the Haldi and IBM test problems on a single processor computer which simulates a multiple processor computer. The algorithm is then implemented on the Denelcor HEP multiprocessor using two of the IBM problems to compare the results of the simulation to the results using an MIMD computer. Finally the algorithm is …

The Effects Of Word Length, Word Frequency And Word Repetition In Auditory Memory (Lexicon, Verbal Ability, Psycholinguistics), Judith Lutzhoff Scharff

Doctoral Dissertations

Four auditory lexical decision experiments were run to assess the effects of word frequency, word length, and word repetition. Experiment I examined the effects of word length, word frequency, and stimulus repetition on RT. The results demonstrated a significant main effect for length and frequency and a significant length by frequency interaction. Long words showed the greatest frequency effect. There was no significant repetition effect. In this experiment the repeated stimuli were separated by at least seven minutes. Experiment II examined the effect of stimulus repetition with the repeated stimuli separated by 0-15 stimuli. This experiment demonstrated a significant repetition …

The Synthesis, Characterization, And Reactions Of Diphosphine Monoxide Complexes Of Selected Transition Metals, Fontaine Cosby Bradley

Doctoral Dissertations

The synthesis, characterization and reactions of transition metal complexes containing diphosphine oxide, R(,2)P-P(O)PR(,2), and diphosphoxane, R(,2)P-O-PR(,2), ligands have been studied. The diphosphoxane tautomer, which is unstable in the free state has been observed to be stabilized by coordination to Mo(O) and Cu(I).

The reactivity of cis-(CO)(,4)Mo(R(,2)P-O-PR(,2)) (R = Ph, ptolyl) towards halogen-oxidation has been studied. The new seven-coordinate complexes (CO)(,3)Mo(R(,2)P-O-PR(,2))X(,2) (R = Ph, X = I; R = p-tolyl, X = Br), as well as the known (CO)(,3)Mo(Ph(,2)PCH(,2)PPh(,2))I(,2) have been observed to exhibit temperature dependent ('31)P NMR consistent with rapid topological isomerization and intramolecular rearrangement of a given isomer.

The …

From Strawbery Banke To Puddle Dock: The Evolution Of A Neighborhood, 1630-1850 (Urban Community, Maritime; New Hampshire), John Walter Durel

Doctoral Dissertations

This dissertation examines the evolution of a site from 1630 to 1850. Until 1690 the site was part of a large farmstead; during the eighteenth century it became a thriving commercial area in the seaport town of Portsmouth, New Hampshire; after 1820 it became an old waterfront neighborhood serving primarily as a residential area. The study first places the site within the context of the larger community, and then looks at spatial arrangements and structural forms within the site itself. Finally it follows the changing reputation of the area.

The local economy was the strongest influence on the way people …

Solar Modulation Of Galactic Cosmic Rays: Techniques & Applications (Shock Acceleration, Antiprotons), John Steven Perko

Doctoral Dissertations

This thesis covers four topics in the theory of interplanetary cosmic-ray propagation:

The first part involves the time-dependent, spherically-symmetric, solar modulation of galactic cosmic rays. A numerical technique was introduced for the solution of this problem. A model for the solar-cycle variation in cosmic-ray intensity illustrated this method, using enhanced particle scattering regions. This model accounted for at least three key sets of observations: the cosmic-ray radial intensity gradients; the decrease in cosmic-ray intensity over the solar cycle; and the hysteresis between low and high-energy cosmic rays.

The second section contains an attempt to explain recent observations which show that …

Some Problems In Bayesian Inference In A Nonclassical Setting (Operational Statistics, Betting Rates, Coherence), Carolyn Margaret Magness

Doctoral Dissertations

The Bayesian inference strategy is studied within the framework of operational statistics (generalized sample spaces). Conditions necessary and sufficient for consistency and strict consistency of a complete betting rate assignment are derived. A constructive proof is given of the existence of a unique second-order probability which induces a given consistent and countably additive complete betting rate assignment. Continuity of the Bayesian inference strategy is investigated. Asymptotic properties of the Bayesian inference strategy are examined both at the level of betting rates and at the level of second-order probabilities.

The Making Of An American Author: Melville And The Idea Of A National Literature, Daniel Ware Reagan

Doctoral Dissertations

In this study I examine the ways in which the idea of a national literature affected the development of both Herman Melville's career and of his reputation through 1930. Melville, as a member of the New York literary group Young America, participated in an effort to define and create a national literature. His apprenticeship was served under the influence of Young America, and the group's ideas about the act of writing, the defining qualities of a national work, and the relationship of writer and reader influenced the shape of his career. Although Melville's exploration into the implications of Young America's …

Ecology Of Rocky Subtidal Communities: The Role Of Modiolus Modiolus (L) And The Influence Of Disturbance, Competition, And Mutualism, Jon Drew Witman

Doctoral Dissertations

This study presents an analysis of physical and biological processes regulating the structure of rocky subtidal communities off coastal New Hampshire and southern Maine, USA, with emphasis on the ecology of the horse mussel Modiolus modiolus (L.). Quantitative sampling and multivariate analysis revealed 3 communities: (1) Modiolus community; (2) 30 m community of species with highest densities outside mussel beds; (3) 8-18 m community of species with maximal densities outside mussel beds.

Controlled field experiments, a natural grazing experiment, and long-term photographic monitoring (5 yrs) enabled patterns of Modiolus community structure to be related to the processes maintaining them. Bivalve, …