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The dynamic nuclear polarization of hydrogen nuclei by the solid effect in single crystals of samarium doped lanthanum magnesium nitrate (Sm:LMN) has been studied theoretically and experimentally. The equations of evolution governing the dynamic nuclear polarization by the solid effect have been derived in detail using the spin temperature theory and the complete expression for the steady-state enhancement of the nuclear polarization has been calculated. For well-resolved solid effect transitions at microwave frequencies Ï ~ Ï _e ± Ï _n, the expression for the steady-state enhancement differs from the expression obtained by the rate equation approach by small terms which become zero at Ï ~ Ï _e ± Ï _n Experimental enhancements of the proton polarization were obtained for eight crystals at 9.2 GHz and liquid helium temperatures. The samarium concentration ranged from 0.1 percent to 1.1 percent as determined by X-ray fluorescence. A peak enhancement of 181 was measured for a 1.1 percent Sm:LMN crystal at 3.0^" K. The maximum enhancements extrapolated with the theory using the experimental data for peak enhancement versus microwave power and correcting for leakage, agree with the ideal enhancement (24O in this experiment) within experimental error for three of the crystals. The calculated satellite separation was within 6 percent of the measured separation for each of the enhancement curves and the peak positive and negative enhancements were equal for all but two of the crystals. The nuclear spin"lattice relaxation time was measured for one of the crystals between l.6^" K and 4.2^" K. To account for nuclear spin"lattice relaxation, spin diffusion theory in the rapid airrusion limit was incorporated into the results of the spin temperature theory of the solid effect. The experimental results indicate that the spin temperature theory is a quantitatively correct approach for the description of dynamic nuclear polarization by the solid effect for well"resolved solid effect transitions. / Ph. D.

Halogenated monocyclic and bicyclic heteroaromatic azines, possessing a six or ten w-electron system and one or two ring nitrogens, have been shown to undergo nucleophilic displacement of halide ion with a variety of nucleophiles. A detailed review of the relative reactivity of compounds of these classes, as well as halogenated heteroaromatic azines containing as many as four nitrogen atoms has appeared. / Ph. D.

Introduction: Increased temperature as a stress factor in aquatic environments has recently received much attention. Human population growth accompanied by expanded demands for electrical energy has resulted in increased construction of power generating facilities. Conventional fossil fuel power plants are being built to produce many times the electricity of those built in previous years. Nuclear power plants, not economically feasible in small sizes, are being constructed to generate even more electrical energy per unit than the new conventional units. Nuclear power facilities produce heat less efficiently and, thus, require approximately fifty percent more cooling per BTU than usual methods (Kolflat, 1968). Increased exposure of populations and communities of aquatic organisms to thermal pollution can thus be anticipated when natural water systems are utilized as a cooling source. The majority of research effort relative to the effects of heated waste waters on aquatic systems has been directed towards macro- as opposed to micro-organisms. While the use of microorganisms in general pollution monitoring is not a nevi concept; for examples see Kolkwitz and Marsson (1908); Butcher (1947); Fjerdingstad (1962), most of the existing effort has been in the area of correlation of species to various polluted situations. The major disadvantages of such approaches as well as the use of populations and communities of microorganisms in pollution monitoring are discussed in Cairns and Lanza (1971) and Cairns, etc. (submitted)... <i>Vita removed Nov. 30, 2011. GMc</i> / Ph. D.

Random or stochastic integral equations occur frequently in the mathematical description of random phenomena in engineering, physics, biology, and oceanography. The present study is concerned with random or stochastic integral equations of the Volterra type in the form x(t;w) = h(tiW) + fa k(t,T~w)f(T,x(Tjw»dT, t > 0, and of the Fredholm type in the form 00 x(tjw) = h(t:w) + fa ko(t,T;w)e(T,x(T;w»dT, t ~ 0, where w £ Q, the supporting set of a complete probability measure space (n,A,p). A random function x(t:w} is said to be a random solution of an equation such as those above if it satisfies the equation with probability one. It is also required that X(tiW) be a second order stochastic process. The purpose of this dissertation is to investigate the existence, uniqueness, and stochastic stability properties of a random solution of these Volterra and Fredholm stochastic integral equations using the "theory of admissibility" and probabilistic functional analysis. The techniques of successive approximations and stochastic approximation are employed to approximate the random solution of the stochastic Volterra integral equation, and the convergence of the approximations to the unique random solution in mean square and with probability one is proven. Problems in telephone traffic theory, hereditary mechanics, population growth, and stochastic control theory are formulated, and some of the results of the investigation are applied. Finally, a discrete version of the above random integral equations is given, and several theorems concerning the existence, uniqueness, and stochastic stability of a random solution of the discrete equation are proven. Approximation of the random solution of the discrete version is obtained, and its convergence to the random solution is studied. This work extends and generalizes the work done by C. P. Tsokos in Mathematical Systems Theory 3 {1969}, pages 222-231, and M. W. Anderson in his Ph.D. dissertation at the University of Tennessee, 1966, among others. Extensions:of this research to several areas of application are proposed. / Ph. D.

Scale insects are among the most serious plant pests throughout the world. The Diaspididae is the largest scale insect family and probably the most important economically. No comprehensive taxonomic study dealing with the scale insects of Venezuela has been conducted in the past. Forty-nine species are described and illustrated in this study, of which 2 are new species. Twenty-seven additional species are recorded from Venezuela for the first time. Keys are provided for determination of the 49 species. The material studied was borrowed from several institutions. Mounting techniques are given. The description of each species is based on females, since males and nymphs were available only in a few species. While this is essentially a taxonomic and faunistic study, the hosts on which the scale insects were found are listed. It is hoped that this study would be used as basis for future research in Venezuela. More collections need to be made throughout the many ecologically different areas of the country; especially from non-cultivated plants. The accumulation of additional distributional and biological records, and will lead to a better understanding of the Venezuelan armored scale insect fauna. / Ph. D.

The purpose of this investigation was to test the effect of sample size and carrier gas flowrate on the efficiency (relative to an analytical column) of an annular preparative-scale column. The chromatographic system for this investigation consisted of η-methyl-butyrate injections with nitrogen carrier gas and a liquid phase of Craig polyester succinate on Chromosorb W. The analytical column had an inside diameter of 0.061 inches. The preparative-scale column had an outside diameter of 2.075 inches and an inside diameter of 1.050 inches. The operating temperature for both columns was 215 degrees Fahrenheit. A sample size range of 0.1 to 3.0 milliliters was studied on the preparative-scale unit; this corresponded to a 0.2 to 3.6 microliter range on the analytical unit. Carrier gas flowrates of 4305, 8610 and 17,220 milliliters per minute were studied on the preparative-scale unit. This corresponded to flowrates of 5, 10 and 20 milliliters per minute on the analytical unit. Preparative-scale efficiencies of 20.43, 41.95 and 45.34 per cent were obtained at a sample size of 0.1 milliliter. The above efficiencies correspond to flowwates of 4305, 8610 and 17,220 milliliters per minute. As the sample size was increased to 3.0 milliliters the corresponding efficiencies dropped to 7.20, 17.71 and 27.11 per cent respectively. / Master of Science

A gas chromatographic study was made to quantitatively analyze the effluents produced during the thermal cyclization of several polyimidazopyrrolone (pyrrone) model compounds. The study yielded information on analogous polymeric reactions. The model compounds were programed at 5° C/min from 25° to 400° C and volatile species were purged into a gas chromatograph at 25° intervals. An analysis of the effluents revealed that the cyclization reactions are concerted and generally occur below 250°C. The percent of conversion of the model compounds is readily determined by quantitating those reaction products amenable to gas chromatographic analysis. Only the amide-acid-amine and meta-benzimidazole-acid model compounds exhibited complete conversion to the pyrrone structure. Evidence that decarbo:xylation has occurred in the other compounds is presented. / Master of Science

Mapping of a 190 square km area along the western flank of the Blue Ridge anticlinorium in central Virginia has defined three major rock groups: (1) the earlier Precambrian Virginia Blue Ridge Complex; (2) the Late Precambrian Catoctin Group; and (3) the Early Cambrian Chilhowee Group. The Virginia Blue Ridge Complex is subdivided from oldest to youngest into the Pedlar, Marshall and Levingston formations. The Pedlar and Marshall formations, partially of metasedimentary origin, were metamorphosed to the granulite facies, retrograded to as low as the greenschist facies, and deformed into a series of east-trending folds prior to Late Precambrian. The relationships between the two metamorphic events and structural deformation was not determined. An angular unconformity separates the Catoctin Group from the Virginia Blue Ridge Complex upon which 300 m of topographic relief was developed. The Catoctin Group is subdivided from oldest to youngest into the Swift Run, Catoctin and Loudoun formations which are subdivided into phyllitic units of both sedimentary and pyroclastic origin separated by sequences of greenstone flows. Early Catoctin Group volcanism, originating in situ from northeast-trending dike complexes, was accompanied by normal faulting along the northwest-trending Stony Creek fault. Swift Run and lower Catoctin Formation sediments were transported principally from the southeast quadrant or were derived in situ from saprolite and colluvial deposits. Loudoun and upper Catoctin Formation arkosic sediments were derived from localized sources, west of the Blue Ridge, and transported in a southwesterly direction parallel to the Appalachian structural trend. Pyroclastics of the Catoctin Group probably were derived from a northwest source. The upper Catoctin Formation is older than 700 my. Paleozoic metamorphism of the Catoctin Group altered the lava flows toward the following greenschist assemblages of high oxidation state: quartz and albite plus (1) epidote, penninite and magnetite; or (2) penninite, magnetite and calcite. Subsequently, metamorphism indicative of a lower oxidation state altered the lavas toward the greenschist assemblage of: quartz, albite, epidote and actinolite. Actinolite content increases with depth at the expense of relict pyroxene, penninite and magnetite. Metamorphosed pyroclastics are characterized by sericite, quartz, magnetite and/or hematite. The Chilhowee Group is subdivided, from oldest to youngest, into the Weverton, Harpers and Antietam formations. A thrust fault zone separates metamorphosed Weverton and Harpers elastics from unmetamorphosed Antietam elastics. Metamorphosed Chilhowee and Catoctin sediments are characterized by formation of the following metamorphic minerals: epidote, penninite, sericite, and microcrystalline quartz. Chilhowee detritus was derived from the west-northwest and transported eastward and/or parallel to the Appalachian structural grain. Post-Precambrian deformation includes folding about northeast and north-trending axes followed by development of southeast-dipping cleavage during Paleozoic metamorphism. Cleavage development preceded northwestward thrusting of metamorphosed rocks of the Blue Ridge over unmetamorphosed Paleozoic rocks of the Valley and Ridge. Subsequently the principal joint trends were established followed by normal and strike-slip movement along northeast-trending high-angle faults. Intrusion of Mesozoic dikes post-dates high-angle faulting. / Ph. D.