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Full-Text Articles in Physical Sciences and Mathematics

The Role Of Picoplankton In Phytoplankton Dynamics Of A Temperate Coastal Plain Estuary, Robert Triau Ray Jan 1986

The Role Of Picoplankton In Phytoplankton Dynamics Of A Temperate Coastal Plain Estuary, Robert Triau Ray

Dissertations, Theses, and Masters Projects

No abstract provided.


Peroxo Complexes Of Vanadium(V) And Molybdenum(Vi) With Nicotine And Aspartic Acids, Sandra Jean Sheffield Jan 1986

Peroxo Complexes Of Vanadium(V) And Molybdenum(Vi) With Nicotine And Aspartic Acids, Sandra Jean Sheffield

Dissertations, Theses, and Masters Projects

No abstract provided.


Contribution To The Hydrobiology Of The York River: Predicting Surface Mixed Layer Depth (Destratification, Tidal, Semilunar, Virginia), Donald Max Hayward Jan 1986

Contribution To The Hydrobiology Of The York River: Predicting Surface Mixed Layer Depth (Destratification, Tidal, Semilunar, Virginia), Donald Max Hayward

Dissertations, Theses, and Masters Projects

Destratification in the York River, USA, during high spring tides is the result of the interruption of normal two-layer estuarine flow by advection of relatively fresh water in to the River mouth from the Chesapeake Bay. This is due to the presence of a longitudinal salinity gradient in the Bay and a difference of tidal current phase between the River and the Bay. Similar behavior is seen in other subestuaries of the Chesapeake Bay and may be common in subestuary-estuary interactions. Correlation and regression analysis are used to examine relationships between stratification variation in the lower York River and a …


The Cure Reaction Of An Aromatic Thermosetting Polyimide, Michael Edward Whitham Jan 1986

The Cure Reaction Of An Aromatic Thermosetting Polyimide, Michael Edward Whitham

Dissertations, Theses, and Masters Projects

No abstract provided.


Reproductive Ecology, Population Dynamics And Seasonal Movements Of The Hogchoker (Trinectes Maculatus), In The Elizabeth River, Virginia, Stephen M. Smith Jan 1986

Reproductive Ecology, Population Dynamics And Seasonal Movements Of The Hogchoker (Trinectes Maculatus), In The Elizabeth River, Virginia, Stephen M. Smith

Dissertations, Theses, and Masters Projects

No abstract provided.


Formation Of Longitudinal Dispersion Coefficient In Partially Mixed Estuaries And Application In A One-Dimensional Real-Time Model, Anne Catherine Wilber Jan 1986

Formation Of Longitudinal Dispersion Coefficient In Partially Mixed Estuaries And Application In A One-Dimensional Real-Time Model, Anne Catherine Wilber

Dissertations, Theses, and Masters Projects

No abstract provided.


The Use Of Crab Meal As A Supplemental Food For Juvenile Hard Clams (Mercenaria Mercenaria), Patricia Lynn Duncan Jan 1986

The Use Of Crab Meal As A Supplemental Food For Juvenile Hard Clams (Mercenaria Mercenaria), Patricia Lynn Duncan

Dissertations, Theses, and Masters Projects

No abstract provided.


Lateral Variability In A Coastal Plain Estuary (Fronts, Density, Lateral Circulation), Linda Mary Huzzey Jan 1986

Lateral Variability In A Coastal Plain Estuary (Fronts, Density, Lateral Circulation), Linda Mary Huzzey

Dissertations, Theses, and Masters Projects

A series of observations of the density distribution across the York River estuary documents distinct lateral differences in density and degree of vertical mixing. The magnitude of the density differences varies throughout the tidal cycle; maximum lateral gradients occur at times of minimum current. When the density distribution is sufficiently inhomogeneous, longitudinal estuarine fronts are generated. These fronts are axially aligned, up to several miles in length, and are apparent for less than 2 hours at any given location. Although the density difference across the frontal boundary is often small, horizontal pressure gradients acting over a broad frontal region generate …


The Sedimentary Processes And Geomorphic History Of Wreck Shoal, An Oyster Reef Of The James River, Virginia, Joseph T. Dealteris Jan 1986

The Sedimentary Processes And Geomorphic History Of Wreck Shoal, An Oyster Reef Of The James River, Virginia, Joseph T. Dealteris

Dissertations, Theses, and Masters Projects

Wreck Shoal is a subtidal oyster reef area located in the James River, Virginia. Two significantly different types of oyster reefs are found in adjacent areas on Wreck Shoal. Hard-rock reefs are characterized by a relatively thick oyster shell layer, higher densities of live oysters, a coarser interstitial sediment, and a negligible sediment cover. In contrast, mud-shell reefs are characterized by a very thin osyter shell layer, considerably lower densities of live oysters, a finer interstitial sediment, and a 1-2 cm layer of very fine sediments covering the reef. The contemporary sedimentation processes operating on the hard-rock and mud-shell oyster …


The Late Quaternary Evolution Of A Twin Barrier-Island Complex, Cape Charles, Virginia (Stratigraphy, Sedimentology, Wisconsinan, Sea-Level Highstand), Kenneth. Finkelstein Jan 1986

The Late Quaternary Evolution Of A Twin Barrier-Island Complex, Cape Charles, Virginia (Stratigraphy, Sedimentology, Wisconsinan, Sea-Level Highstand), Kenneth. Finkelstein

Dissertations, Theses, and Masters Projects

A total of 68 vibra-cores and 14-box cores in conjunction with high-resolution seismic records are used to describe the late Quaternary development of a twin-barrier island complex. Based on the stratigraphy, radiocarbon dates, and microfossils, a transgressive outer Holocene and inner Pleistocene barrier island complex are recognized. The two subaerial sub-parallel barriers are a result of separate marine transgressions that occurred before and after late Wisconsin glaciation. Pollen assemblages and ten radiocarbon dates from the lagoonal sediments below the older island concur on a date of approximately 30,000 years B.P., hence a probable mid-Wisconsinan age for the overriding barrier island. …


The Role Of Science And Scientists In Marine Environmental Policy And Management, Teny Topalian Jan 1986

The Role Of Science And Scientists In Marine Environmental Policy And Management, Teny Topalian

Dissertations, Theses, and Masters Projects

The role of science and scientists in environmental policy and management is and has been an important, complex, and controversial subject for many years. The objective of this study is to determine how science and scientists interact in environmental policy formation and management and how science is or could be used in the development of policy which can ultimately be used as a basis for effective resource management plans. In the very broad sense this study attempts to evaluate the general hypothesis that "Scientists do not play a role in promoting or encouraging science as a means of changing attitudes …


Geological History Of A Holocene Drainage System: Hack Creek, Virginia, Robert A. Gammisch Jan 1986

Geological History Of A Holocene Drainage System: Hack Creek, Virginia, Robert A. Gammisch

Dissertations, Theses, and Masters Projects

No abstract provided.


Biological Review And Commercial Whelk Fisheries Analysis Of Busycon Carica With Comments On B Canaliculatum And B Contrarium In Virginia, Jane Dicosimo Jan 1986

Biological Review And Commercial Whelk Fisheries Analysis Of Busycon Carica With Comments On B Canaliculatum And B Contrarium In Virginia, Jane Dicosimo

Dissertations, Theses, and Masters Projects

No abstract provided.


Parasite Community Structure In Summer Flounder: Paralichthys Dentatus (Linnaeus), Of The Chesapeake Bay, Maura E. Jansen Jan 1986

Parasite Community Structure In Summer Flounder: Paralichthys Dentatus (Linnaeus), Of The Chesapeake Bay, Maura E. Jansen

Dissertations, Theses, and Masters Projects

No abstract provided.


A Morphological Study Of The Pharyngeal Sac Of Two Species Of Stromateid Fishes: Perrilus Triacanthus And P Paru, Thomas R. Sminkey Jan 1986

A Morphological Study Of The Pharyngeal Sac Of Two Species Of Stromateid Fishes: Perrilus Triacanthus And P Paru, Thomas R. Sminkey

Dissertations, Theses, and Masters Projects

No abstract provided.


Recommendations For Amelioration Of Legal And Environmental Concerns About Mining Of Deepsea Deposits Of Polymetallic Sulfides, Michael P. De Luca Jan 1986

Recommendations For Amelioration Of Legal And Environmental Concerns About Mining Of Deepsea Deposits Of Polymetallic Sulfides, Michael P. De Luca

Dissertations, Theses, and Masters Projects

No abstract provided.


Stratigraphy And Heavy Mineral Analysis In The Lower Chesapeake Bay, Virginia, C. R. Berquist Jr Jan 1986

Stratigraphy And Heavy Mineral Analysis In The Lower Chesapeake Bay, Virginia, C. R. Berquist Jr

Dissertations, Theses, and Masters Projects

Spatially continuous patterns of heavy mineral distributions in three dimensions characterized the sandy Holocene sediments of the lower Chesapeake Bay. A pilot study using Q-mode factor analysis on data from an earlier study determined mineral assemblages and mineral composition gradients; the gradients suggested that surficial sediments entered the Bay from offshore and from older deposits to the west. Principal components analysis of the same data indicated that the abundances of only 5 out of 21 minerals were adequate to explain most of the mineral variance. The mineralogy of 87 samples from cores defining two geologic cross-sections was added to the …


The Synthesis Of Hindered Aliphatic Ketones For The Future Production Of Spiro [4.5] Decane Sesquiterpenes, Stephen Lee Hodges Jan 1986

The Synthesis Of Hindered Aliphatic Ketones For The Future Production Of Spiro [4.5] Decane Sesquiterpenes, Stephen Lee Hodges

Dissertations, Theses, and Masters Projects

No abstract provided.


Secondary Isotope Effects Of Nucleophilic Vinylic Substitution, Paul Frederick Drees Jan 1986

Secondary Isotope Effects Of Nucleophilic Vinylic Substitution, Paul Frederick Drees

Dissertations, Theses, and Masters Projects

No abstract provided.


Effect Of Strain On Muon Diffusion And Trapping In Metal By Bassam Salim Hitti, Bassam Salim Hitti Jan 1986

Effect Of Strain On Muon Diffusion And Trapping In Metal By Bassam Salim Hitti, Bassam Salim Hitti

Dissertations, Theses, and Masters Projects

Positive muons implanted in metal distort the surrounding lattice; therefore, in addition to electronic interactions, the elastic forces have to be considered in determining the muon state. to explore the elastic and electronic diffusion and trapping mechanisms, we studied AlCu(,420ppm), AlMg(,1000ppm) and AlAg(,1000ppm) alloys. These alloys were selected for the different effects on the host lattice of these impurities; Cu contracts the Al lattice, Mg expands it and Ag has nearly no effect. On the other hand Cu and Ag are monovalent while Mg is divalent. For AlCu between 5K and 14K the temperature exponent (beta) of the two-state-model trapping …


Determination Of The Vacancy Migration Energy Of Aluminum By Nmr, Terry William Gullion Jan 1986

Determination Of The Vacancy Migration Energy Of Aluminum By Nmr, Terry William Gullion

Dissertations, Theses, and Masters Projects

Monovacancy diffusion is a thermally activated process characterized by an activation energy E(,d). The diffusion of atoms requires the formation and migration of vacancies. The concentration of vacancies n/N is given by n/N (DBLTURN) exp(-E(,f)/kT). It can be shown that the activation energy E(,d) is the sum of the energy to form a vacancy E(,f) and the energy required for an atomic jump E(,m): E(,d) = E(,f) + E(,m). Furthermore, the atomic jump rate (omega)(,j) can be shown to be thermally activated and given by (omega)(,j) (DBLTURN) (nu)(,o)(n/N)exp(-E(,m)/kT) ((nu)(,o) is the attempt frequency).;NMR offers many techniques to measure the activation …


Rydberg Atoms In Parallel Electric And Magnetic Fields, Robert Leonard Waterland Jan 1986

Rydberg Atoms In Parallel Electric And Magnetic Fields, Robert Leonard Waterland

Dissertations, Theses, and Masters Projects

I have calculated the energy spectrum of a highly excited atom which lies in parallel, static electric and magnetic fields. In parallel fields the Coulomb quantum numbers n and m are still "good" quantum numbers but 1 is not: the calculation is for n = 30, m = 1 atoms.;The eigenvalues were obtained by semi-classical quantisation of first-order classical perturbation theory and have been calculated for a large range of electric and magnetic field strengths. The results are in good agreement with those found from first-order degenerate quantum perturbation theory.;The semi-classical analysis provides a correlation diagram connecting the Stark effect …


Morphometric And Meristic Stock Identification Of Summer Flounder (Paralichthys Dentatus), Glenn Roger Delaney Jan 1986

Morphometric And Meristic Stock Identification Of Summer Flounder (Paralichthys Dentatus), Glenn Roger Delaney

Dissertations, Theses, and Masters Projects

No abstract provided.


Estuary Water Movement, John Dickerson Mitchell Jan 1986

Estuary Water Movement, John Dickerson Mitchell

Dissertations, Theses, and Masters Projects

No abstract provided.


Fluctuations In The Catchability Coefficient Of Atlantic Menhaden, 1968-1982, Steven M. Atran Jan 1986

Fluctuations In The Catchability Coefficient Of Atlantic Menhaden, 1968-1982, Steven M. Atran

Dissertations, Theses, and Masters Projects

No abstract provided.


Carbon Alkylation Of 2-Phenylthio-1,3-Cyclopentanediones, Karol Renee Parham Jan 1986

Carbon Alkylation Of 2-Phenylthio-1,3-Cyclopentanediones, Karol Renee Parham

Dissertations, Theses, and Masters Projects

No abstract provided.


The Stereospecific Synthesis Of Tetrahydropyrans And Tetrahydrofurans, Rhonda Carol Winstead Jan 1986

The Stereospecific Synthesis Of Tetrahydropyrans And Tetrahydrofurans, Rhonda Carol Winstead

Dissertations, Theses, and Masters Projects

No abstract provided.


Peroxo Complexes Of Molybdenum (Vi) And Vanadium (V) With Imidazole And Histidine, Jennifer Lisa Gundersen Jan 1986

Peroxo Complexes Of Molybdenum (Vi) And Vanadium (V) With Imidazole And Histidine, Jennifer Lisa Gundersen

Dissertations, Theses, and Masters Projects

No abstract provided.


Low-Energy Collisions Of Alkali-Metal Anions, David M. Scott Jan 1986

Low-Energy Collisions Of Alkali-Metal Anions, David M. Scott

Dissertations, Theses, and Masters Projects

Measurements of the total cross section for electron detachment, (sigma)(,e)(E), are presented for low-energy (E(,1ab) < 300 eV) collisions of Na('-), K('-), and Cs('-) with atomic and molecular targets. For many of the atomic (rare-gas) targets, the energy dependence of (sigma)(,e)(E) is striking: virtually no detachment is observed until relatively high collision energies (50 eV in the center-of-mass frame) are reached, in contradistinction to what has been observed for similar collisions involving H('-). The thresholds for alkali anion detachment are approximately equal to the thresholds for excitation observed in collisions of neutral alkali atoms with these same targets. The similarity between the dynamics of the neutral system and that of the negative ion system, together with the observation (at greater energies) of detachment accompanied by excitation of the alkali parent, suggests that electron detachment may be mediated by a two-electron process in some cases. A simple curve-crossing mechanism adequately reproduces the observed (sigma)(,e)(E) for several of these rare-gas targets.;Measurements of both (sigma)(,e)(E) and the cross section for charge transfer (sigma)(,i)(E) have also been completed for H(,2), D(,2), N(,2), O(,2), CO, CO(,2), SO(,2), N(,2)O, CH(,4), and SF(,6) targets. Electron detachment is the dominant process for all of these targets except O(,2), SO(,2), and SF(,6), with thresholds on the order of a few eV. Structure in (sigma)(,e)(E) for the CO(,2) target has been attributed to charge transfer to a metastable state of CO(,2)('-)(('2)A(,1)). Similarly, in the case of N(,2)O, both (sigma)(,e)(E) and (sigma)(,i)(E) exhibit behavior which suggests that a temporary negative ion state is formed during the collision. In the case of the O(,2), SO(,2), and SF(,6) targets, charge transfer is observed to have particularly large cross sections (>100 (ANGSTROM)('2)) at low collision energies.


A Nuclear Magnetic Resonance Study Of Deuterated Poly(Vinylidene Fluoride) And A Copolymer Of Deuterated Vinylidene Fluoride And Tetrafluoroethylene, Montee A. Doverspike Jan 1986

A Nuclear Magnetic Resonance Study Of Deuterated Poly(Vinylidene Fluoride) And A Copolymer Of Deuterated Vinylidene Fluoride And Tetrafluoroethylene, Montee A. Doverspike

Dissertations, Theses, and Masters Projects

Pulsed deuterium NMR experiments have been performed on deuterated samples of poly(vinylidene fluoride), PVF(,2), repeat unit CH(,2)CF(,2) and the copolymer poly(vinylidene fluoride)-tetrafluoroethylene (80-20), (PVF(,2)-F(,4)E). A deuterium line shape study has been employed to characterize the orientational distribution of the dipole moments in both poled and unpoled samples. In addition, the orientational distributions of chain axis alignment has been measured in stretched samples.;PVF(,2) and PVF(,2)-F(,4)E exhibit unique piezoelectric and pyroelectric properties which are due to their crystalline components (approximately 50% in typical material). Four crystalline phases exist in the homopolymer PVF(,2), the (alpha), (beta), (gamma), and the (delta). The relatively electrically …