Digital Commons Network^™

Self-Diffusion Studies In Polymer-Solvent Systems By Pulsed-Gradient Spin-Echo Nuclear Magnetic Resonance, R. Allen Waggoner

Doctoral Dissertations

"Pulsed gradient NMR techniques have been used to study self-diffusion in polymer solutions. The systems studied include toluene, cyclohexane, ethylbenzene, chloroform, t-butyl acetate, and methyl ethyl ketone in polystyrene; methyl methacrylate in poly(methyl methacrylate); poly(ethylene oxide) in water; and water in biological tissue. The polymer diffusion data are evaluated in terms of scaling theory as they relate to the scaling of the polymer diffusion coefficient with molecular weight. The solvent diffusion data are evaluated with kinetic and free-volume theories. In addition a relatively simple dependence of diffusion coefficient on polymer volume fraction is derived from free-volume theory. The solvent diffusion …

I Asymmetric Photochemistry Ii Exploratory And Mechanistic Studies On The Triplet Sensitized Vapor Phase Photochemistry Of Allenes Iii Developments In The Synthesis Of Strained Cyclic Cumulenes, William Calvin Shakespeare

Doctoral Dissertations

The development and implementation of a new chiral triplet sensitizer derived from 1,1$\sp\prime$-binaphthol is described. Irradiation of 1,3-diphenylallene (16) in the presence of 4,5,6,7-tetrahydro-dinaphtho(2,1-g:1$\sp\prime,2\sp\prime$-i) (1,6) dioxecine (10) resulted in 0.66% optical induction. Irradiation of 1,3-cyclooctadiene (17) in the presence of 10 resulted in 11.3% optical induction. The singlet state of 10 could be effectively quenched by higher diene concentration, substantially reducing the optical yield. Irradiation of trans-1,2-diphenyl-cyclopropane (1) in the presence of 10 resulted in very low optical yields.

The mechanism by which triplet excited state allenes react in the vapor phase is investigated through both theory and experiment. Benzene …

Studies Of Rotationally Inelastic Collisions In Argon + Hydrogen Fluoride, James J C Barrett

Doctoral Dissertations

In this dissertation we examine rotationally inelastic collisions involving an atom plus a diatom. We concentrate specifically on the Ar + HF system. In these investigations we employ a number of theoretical methods, including classical trajectories, quantum close-coupled calculations and semiclassical methods, to examine the differential cross sections in Ar + HF. We also investigate the effects of various "sudden" approximations on the scattering dynamics and the limitations of these approximations.

Through this work we were able to identify a new quantum feature in rotationally inelastic scattering. By studying the time evolution of transition amplitudes (rather than probabilities) we are …

A Model Of Electronic Warfare Systems Acquisition And Engineering For Saudi Arabia, Negaa M. Albegami

Doctoral Dissertations

"A major activity within the systems engineering process is the requirements definition and analysis phase. In technical systems, planning this phase looks too technical for top management and too broad for the engineers specialized in narrow technical fields. This categorization (too technical/too broad) represents a gap between top management and specialized engineering. In Saudi Arabia, such a gap is believed to be very wide.

The main objective of this research is to find a way to narrow this gap between management and engineering when planning government systems, especially in electronic warfare (EW) systems. A solution in this effort is to …

Galvanic Stripping Of Fe⁺³ And Pb⁺² Ions And Dissolution Of Metallic Fe, Zn, Pb And Cd Using Di(2-Ethylhexyl)Phosphoric Acid, Luis Miguel Chia Aquije

Doctoral Dissertations

"Two systems were evaluated using the principles of the galvanic stripping process. One of them, the removal of Pb⁺² ions from di-2(ethylhexyl) phosphoric acid (D2EHPA) was performed using metallic zinc. The other, the removal of Fe⁺³ ions from D2EHPA used metallic iron as reductant and was performed simultaneously with the organic phase using a slightly acidic aqueous solution of hydrochloric acid. In addition, the dissolution of metallic zinc, iron, lead, and cadmium in D2EHPA was studied in order to better understand the anodic step in the mechanism of the galvanic stripping process.

Increased temperature was found to dramatically …

Genetic Algorithms With 3-Parent Crossover, L. Vincent Edmondson

Doctoral Dissertations

"A new genetic algorithm which uses a 3-parent uniform crossover operator is developed and analyzed. Uniform crossover operators are shown to be based on the premise that all bit-level genetic information should be passed from parents to children. The 3-parent uniform crossover operator is shown to adhere to this premise. The 3-parent uniform crossover operator is shown to be better than the 2-parent uniform crossover operator on the De Jong test functions.

Two new genetic algorithms which use 3-parent traditional crossover operators are developed and analyzed. The first uses a strategy of randomly selecting 3 of the 6 children resulting …

Atomic Collision Processes Of Interest In Controlled Thermonuclear Fusion Research, Victor Dewitt Irby

Doctoral Dissertations

"This thesis examines several atomic collisional processes involved in controlled thermonuclear fusion. Specifically, experimental studies have been made on the state- selective single capture reaction

³He²⁺ + He —> ³He⁺(n) + He⁺(n'), (1)

on the double capture reaction

³He²⁺ + H e—> ³He + He²⁺ , (2)

and on the single ionization of atomic targets X

A^q+ + X —> A^q+ + X⁺ + e^- (3)

by charged projectiles A^q+. Reactions (1) and (2) have an importance in plasma energy balance and in …

Arene-Alkene Meta Photocycloadditions And Conjugated Enyne Photorearrangements, Manli Zheng

Doctoral Dissertations

The new advances and synthetic potential of arene-alkene meta photocycloadditions, with the goal of rapid approach to polycyclic molecules, are described. Vinyl cyclohexanecarboxylate has been found to be an efficient alkene moiety to improve the reaction efficiency by reducing formation of polymers during irradiation. Exploration of asymmetric meta photocycloaddition, via chiral auxiliaries, resulted in partial asymmetric induction. Fluorescence studies have led to a better understanding of the reaction mechanism. Intramolecular isotope effect results on meta photocycloaddition remain unexplained.

Conjugated enynes undergo a singlet photorearrangement, resulting in a pseudodegenerate rearrangement. The synthesis of starting materials, characterization of products, studies of the …

Nuclear Structure Studies Of The Oxygen Nucleus Observed With The Quasielastic (Electron, Electron'proton) Reaction, Mark Bancroft Leuschner

Doctoral Dissertations

The spectral function of the $\sp{16}$O(e,e$\sp\prime$p)$\sp{15}$N reaction has been measured in quasielastic parallel kinematics. Momentum distributions are extracted for several discrete states, with special emphasis on the low-lying positive parity states of $\sp{15}$N. Spectroscopic factors and bound state wave functions are deduced from a distorted wave impulse approximation analysis, including coupled channels effects, employing five different optical potentials. The distribution of spectroscopic strength is determined out to E$\sb{m}$ = 40 MeV from a multipole decomposition of the spectral function continuum. The spectroscopic factor of the 2$s$1$d$ shell of $\sp{16}$O, as evidenced by transitions to the positive parity (2s$\sb{1/2}$,1d$\sb{5/2}$) doublet at …

Horizontal Distribution, Feeding Rates And Prey Selectivity Of The Littoral Predator, Polyphemus Pediculus, Anne Turner Packard

Doctoral Dissertations

Littoral planktonic communities have rarely been included in food web dynamics and predator/prey behavior studies of planktonic communities of fresh water ecosystems. Polyphemus pediculus, a typically littoral predaceous cladoceran, is common in lakes and ponds throughout the northern temperate zone.

The patchy distribution of Polyphemus in littoral surface waters necessitates the use of a stratified random sampling regime to estimate and monitor Polyphemus populations. The population in Mirror Lake, NH, increased exponentially after the first appearance of parthenogenetic juveniles in late April. An abrupt decline in the population coincided with the movement of small Micropterus dolomieui fry into littoral areas …

Someone Shot The Rainbow: Emergent Writing Patterns Of Securely And Insecurely Attached, Inner-City First Graders, Cindy Matthews

Doctoral Dissertations

The mother or primary caretaker of an infant establishes a communicative bond which has long-term implications for the child as a symbolizer and learner. John Bowlby's theory of attachment claims the mother is the secure base from which an infant, and later the child, can explore and master her environment, develop a sense of autonomy, and relate to peers. Attachment theory sheds light on the process and products of inner-city, first-grade children's written symbolization, yielding many patterns cogent to the study of emergent literacy.

Fifty-nine first graders participated in a study involving projective measures of attachment and language ability and …

Money, Income And Causality: An Open Economy Reexamination, El-Hachemi Aliouche

Doctoral Dissertations

The positive relationship between the rate of growth of the money supply and the rate of growth of aggregate income is a widely accepted principle in macroeconomics. However, the direction of the causality between these two variables has been an enduring subject of controversy.

Recent developments in time series analysis, particularly those relating to the concepts of integration and cointegration, and the stationary nature of economic time series, promise to help settle the debate on the statistical relationship between money supply growth and income growth. Most of the recent work on this issue, however, has been confined to a closed …

Solar Flares: The Onset Of Magnetic Reconnection And The Structure Of Radiative Slow-Mode Shocks, Peng Xu

Doctoral Dissertations

This is a theoretical study of two magnetohydrodynamic (MHD) processes associated with magnetic reconnection in large solar flares and other related eruptive phenomena.

The first process determines the effect of magnetic reconnection in the corona upon the loss of equilibrium triggered by the slow evolution of the field lines mapping to the region in the photosphere where the flare occurs. The quasi-static MHD equations are solved for a magnetic field configuration which satisfies line-tied boundary conditions during the eruption of the flare. Such boundary conditions occur because the inertial mass of the photosphere plasma is much greater than that of …

On Her Mouth You Kiss Your Own: Lesbian Conversations In Exile, 1924-1936, Luita Deane Spangler

Doctoral Dissertations

This dissertation examines the work of four American lesbian expatriate novelists living and writing in Paris in the years between the two World Wars. Altogether six novels are discussed: The Uncertain Feast (1924), The Happy Failure (1925), and This Way Up (1927) by Solita Solano; The Cubical City (1925) by Janet Flanner; The One Who Is Legion (1930) by Natalie Clifford Barney; and Nightwood (1936) by Djuna Barnes.

Guided by recent conjectures on the significance of sexuality and gender development proposed by such feminist theorists as Luce Irigaray and Monique Wittig, this dissertation explores these six novels for evidence of …

A Comparison Of Methods For Analyzing Intraindividual Change In Student Epistemological Orientation During The Transition To College, Trey Michael Buchanan

Doctoral Dissertations

The ability to measure the development of epistemological beliefs of 235 college students during their first-semester in college was investigated by comparing the results obtained using five different methodological approaches to measuring change. These approaches included the use of the two-wave difference score, the residual change score, the cross-time correlation matrix, repeated measures analysis of variance, and individual growth modeling. A cubic individual growth model was found to be superior to other methods in describing intraindividual differences in dualistic epistemological orientation during the transition to college. An investigation of the existence of systematic interindividual differences in growth as a function …

A Study Of Alpha Decay From The Giant Resonance Region In Carbon Via Inelastic Electron Scattering, David John Deangelis

Doctoral Dissertations

We have excited the giant resonance region in $\sp{12}$C via inelastic electron scattering and have measured the first complete angular correlations for charged particle (p and $\alpha$) emission for this reaction for six values of momentum transfer ranging from 0.24fm$\sp{-1}$ to 0.93fm$\sp{-1}$.

By analyzing the $\alpha$ emission decay channels via the Legendre and resonance formalisms, we unambiguously determined the multipole contributions to the total cross section for $\alpha$ decay to the ground state of $\sp8$Be ($\alpha\sb0$ decay) and have set limits on these contributions for $\alpha$ decay to the first excited state of $\sp8$Be ($\alpha\sb1$ decay). We have found that, …

Fine Structure Of Auroral Particle Acceleration, Kristina Anne Lynch

Doctoral Dissertations

A mass-analyzing capped hemispherical electrostatic analyzer has been developed for the purpose of resolving the mass, energy, and pitch angle distributions of auroral ions. The instrument, the B-field Hemispherical Electrostatic Energy and Pitch Angle Spectrometer (BEEPS), is an extension of the HEEPS instrument, which uses a hemispherical analyzer and microchannel plates to measure the angular and energy distribution of ions. BEEPS uses a toroidal magnetic field constructed from rare-earth permanent magnets to separate ion measurements into two groups, protons and heavier ions. BEEPS was flown in February, 1991, from Poker Flat, Alaska, on the TOPAZ3 sounding rocket.

This sounding rocket …

Social Support, Psychological Distress And The Consequences Of Psychotherapeutic Intervention, David Francis King

Doctoral Dissertations

Several questions about social support and its relation to mental health over the course of psychotherapeutic intervention are investigated. These include: how do different measures of social support relate to each other at entrance to therapy (time 1) and three months later (time 2), how does social support vary with mental health over time, and how do strategies of therapists affect social support of patients?

Forty patients and their therapists (27) at two community mental health centers were interviewed. Four quantitative standardized measures of social support were used: Donald and Ware's social integration measure (1982), McFarlane's (1980) measure of social …

Beliefs, Autonomy, And Mathematical Knowledge, Judy Ann Rector

Doctoral Dissertations

The purpose of this study was to investigate the apparent effects of students' beliefs about mathematics and autonomy on their learning of mathematics. The study utilized a multiple-case study design with analysis by and across cases. The cases represented six high school students enrolled in either Algebra II or Algebra II/Trigonometry. Data was collected in three phases: (a) classroom observations and assessment of the teacher's perception of her role in the learning process, (b) an assessment of students' beliefs about mathematics and autonomy, and (c) an assessment of students' newly formed mathematical constructs on functions.

The beliefs' assessment included observing …

Order, Chaos And Complexity In Discrete Dynamical Systems, John E. Bates

Doctoral Dissertations

A method for analyzing discrete dynamical systems is presented that provides a unified quantitative description of order, chaos and complexity in terms of information flow across system boundaries. Complexity is identified with variability in the relative dominance of order and chaos as systems evolve in time; therefore, purely ordered or purely chaotic behavior is considered simple. This notion of complexity is quantitatively expressed as fluctuation in net information gain.

The method is applied to one-dimensional cellular automata, which are spatially and temporally discrete systems. Evidence is presented for a correlation between information fluctuation and the existence of internally complex propagating …

Polymer Substrates For Fiber-Optic Chemical Sensors, Amy Elizabeth Straub

Doctoral Dissertations

The primary goal of this research was to examine chemical and mechanical properties of polymers designed for a fiber optic chemical sensor based on polymer swelling. A second goal of this research was to develop a temperature sensor that could be used with other fiber optic chemical sensors.

Fiber optic chemical sensors have the capability for remote use, accuracy, sensitivity, selectivity, and ruggedness. Fiber optic sensors based on polymer swelling exploit the rugged features of polymers and fiber optic communications technology for use in remote sensing. A crosslinked polymer changes size in the presence of an analyte. As the polymer …

Resonance Absorption Of Mhd Surface Waves With Applications To The Solar Atmosphere, Guang Yang

Doctoral Dissertations

This thesis studies the physics of resonance absorption of MHD surface waves and examines the effects of velocity shear on the rate of resonance absorption. Theoretical analyses and numerical calculations demonstrate that resonance absorption of MHD surface waves is a viable mechanism for heating of the solar corona.

It is shown that resonance absorption has a very simple physical interpretation in terms of driven harmonic oscillators. This insight greatly simplifies the mathematics and allows a thorough discussion of the solar coronal heating. It is found that resonance absorption of MHD surface waves can occur rapidly enough to heat the solar …

Corrosion Protection Of Metals By Poly(3-Methylthiophene) Coatings, Shouxian Ren

Doctoral Dissertations

Electrochemically prepared poly(3-methylthiophene) (P3MT) films were used as conductive polymer coatings to poise a substrate metal in the passive potential range in corrosive media. To firmly adhere P3MT coatings onto substrate metals, different methods were developed for each metal; stainless steel (430SS), titanium (TiGr2) and carbon steel (C1010). The samples were either pretreated by anodization in phosphate solution to form a uniform porous surface or pitted by chloride ions simultaneously with the formation of an adhesive thin film. Coatings were characterized for various galvanostatic electropolymerization conditions on both platinum and phosphated 430SS (Ph430SS) rotating disk electrodes (RDEs). Both applied current …

A Nonlinear Hybrid And Vr Stepping Motor Analysis Via An Integrated Finite Element And Lumped Parameter Modeling Technique, Steven Roger Huard

Doctoral Dissertations

The work involves the magnetic modeling of a variable reluctance and a hybrid stepping motor. The model combines two traditional methods for creating a magnetic model. Nonlinear two dimensional finite element analysis is combined with nonlinear lumped element modeling to create a three dimension lumped model. The two dimensional finite element analysis is used to numerically calculate the effective reluctance function of the motor tooth region. After the finite element analysis is completed, a two terminal tooth region reluctance element that is a function of both rotor angle and tooth region flux density results. The two terminal lumped element is …

Geochronology And Geochemistry Of The Basement Orthogneisses Of The Araguaia Belt, Brazil, Candido A Veloso Moura

Doctoral Dissertations

Orthogneisses representing the basement rocks of the Araguaia belt (AB), Brazil, are exposed in the core of dome-like structures. Gneisses of trondhjemitic, tonalitic, and granodioritic (TTG) composition constitute the Colmeia Complex, while augen gneiss, of granitic composition, is termed Cantao Gneiss (CG). An Archean age is suggested for the TTG gneisses, although the available Rb-Sr ages for these rocks range between 1.8 and 2.6 Ga. A Rb-Sr age of 1.77 Ga for the CG is interpreted either as a crystallization age or a resetting age.

Geochronological and geochemical studies of the orthogneisses of five of these dome-like structures of the …

A Neural Network-Based Trajectory Planner For Redundant Systems Using Direct Inverse Modeling, Franklin J. Rudolph

Doctoral Dissertations

Redundant (i.e., under-determined) systems can not be trained effectively using direct inverse modeling with supervised learning, for reasons well out-lined by Michael Jordan at MIT. There is a "loop-hole", however, in Jordan's preconditions, which seems to allow just such an architecture. A robot path planner implementing a cerebellar inspired "habituation" paradigm with such an architecture will be introduced. The system, called ARTFORMS, for "Adaptive Redundant Trajectory Formation System" uses on-line training of multiple CMACS. CMACs are locally generalizing networks, and have an a priori deterministic geometric input space mapping. These properties together with on-line learning and rapid convergence satisfy the …

To Rend And Teare The Bodies Of Men: Theology And The Body In Demonic Possession; France, England, And Puritan America, 1550-1700, Julianne Siudowski Cooper-Forst

Doctoral Dissertations

During the Reformation, Protestants attempted to recast their theology in opposition to the Roman Catholic system. They succeeded in most areas. There was, however, one area of theology where this was not true: demonology and spiritual possession. Incidents of demonic possession rose during the second quarter of the sixteenth century, reached a crescendo by the first quarter of the seventeenth century, and except for a flurry or two, died out near the beginning of the eighteenth century. This dissertation examines the published materials relating to the physical phenomena of demonic possession in France, England, and Puritan America from the sixteenth …

Transition From Laminar To Turbulent Flow Around An Airfoil, Chang-Ren Chen

Doctoral Dissertations

"A computational fluid dynamics (CFD) code has been developed for two-dimensional incompressible turbulent flows and employed to solve the Navier Stokes equations around an airfoil of arbitrary shape. A low-Reynolds-number k — e turbulence model including curvature effect was used to consider the gain and loss of turbulent kinetic energy. To include laminar sublayer into the computational domain, a multi-layer grid and a cubic-slpine grid were introduced through a conservative form of coordinate transformation. The flow structure varies with the Reynolds numbers. For an airfoil at low Reynolds numbers (below ten thousand), distinct vortex shedding patterns can be found in …

Constrained Completion: Theory, Implementation, And Results, Daniel Patrick Murphy

Doctoral Dissertations

"The Knuth-Bendix completion procedure produces complete sets of reductions but can not handle certain rewrite rules such as commutativity. In order to handle such theories, completion procedure were created to find complete sets of reductions modulo an equational theory. The major problem with this method is that it requires a specialized unification algorithm for the equational theory. Although this method works well when such an algorithm exists, these algorithms are not always available and thus alternative methods are needed to attack problems. A way of doing this is to use a completion procedure which finds complete sets of constrained reductions. …

The Special Artist In American Culture: A Biography Of Frank Hamilton Taylor (1846-1927), Nancy Louise Gustke

Doctoral Dissertations

As a Special Artist (newspaper illustrator) for papers such as the New York Daily Graphic and Harper's Weekly, author and illustrator of numerous guidebooks, and astute recorder of Philadelphia, Frank Hamilton Taylor left a unique visual and written record of late nineteenth, early twentieth century American life. His work provided the growing, increasingly literate urban middle class with information about their country from the excitement of the Centennial Exposition to the tragedy of lives lost at sea. In addition, Taylor's documentation of leisure pursuits, particularly in the Thousand Islands area of New York, helped define what constituted recreation for the …