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Full-Text Articles in Physical Sciences and Mathematics

Gender Roles And Home Computer Use By Children, Trelles Whitfield D'Alemberte Jan 1991

Gender Roles And Home Computer Use By Children, Trelles Whitfield D'Alemberte

Dissertations, Theses, and Masters Projects

No abstract provided.


The Hydraulic Sorting Of Light And Heavy Minerals, Heavy-Mineral Concentrations, And Grain Size, Sara M. Dydak Jan 1991

The Hydraulic Sorting Of Light And Heavy Minerals, Heavy-Mineral Concentrations, And Grain Size, Sara M. Dydak

Dissertations, Theses, and Masters Projects

No abstract provided.


Food And Feeding Of Northern Bluefin Tuna (Thunnus Thynnus) And Yellowfin Tuna (Thunnus Albarcares): A Comparative Study Of The Food And Feeding Habits Of The Northern Bluefin Tuna Off The Coast Of Virginia, Charles Gilbert Barr Jan 1991

Food And Feeding Of Northern Bluefin Tuna (Thunnus Thynnus) And Yellowfin Tuna (Thunnus Albarcares): A Comparative Study Of The Food And Feeding Habits Of The Northern Bluefin Tuna Off The Coast Of Virginia, Charles Gilbert Barr

Dissertations, Theses, and Masters Projects

No abstract provided.


A Comparison Of Meristics And Morphometrics Between Two Strains Of Pond Cultured Striped Bass (Morone Saxatilis), Steven Gornak Jan 1991

A Comparison Of Meristics And Morphometrics Between Two Strains Of Pond Cultured Striped Bass (Morone Saxatilis), Steven Gornak

Dissertations, Theses, and Masters Projects

No abstract provided.


Stock Enhancement Of Caribbean Spiny Lobster, Panulirus Argus Latrielle, Using Artificial Shelters: Patterns Of Survival And Dynamics Of Shelter Selection, David Bryan Eggleston Jan 1991

Stock Enhancement Of Caribbean Spiny Lobster, Panulirus Argus Latrielle, Using Artificial Shelters: Patterns Of Survival And Dynamics Of Shelter Selection, David Bryan Eggleston

Dissertations, Theses, and Masters Projects

Field tethering experiments in seagrass beds of Bahia de la Ascension, Mexico examined the impact of different-sized artificial shelters upon survival of three juvenile size-classes of the Caribbean spiny lobster, Panulirus argus. The artificial shelters were concrete structures (casitas) that simulate lobster dens. In the tethering experiments, spiny lobster survival was generally higher in smaller than larger casitas, though the effect depended upon the relationship between lobster and shelter size. Thus, spiny lobster survival depends not only upon the availability of shelter, but also on the scaling between shelter size and lobster size. These results suggest that placement of appropriately-scaled …


Monooxygenase Induction And Lethality As Endpoints In Aquatic Toxicology, Daniel W. Sved Jan 1991

Monooxygenase Induction And Lethality As Endpoints In Aquatic Toxicology, Daniel W. Sved

Dissertations, Theses, and Masters Projects

Spot, Leiostomus xanthurus, were exposed to suspended sediments (&\approx&20 mg/L) contaminated with polycyclic aromatic hydrocarbons (PAH) in a laboratory flow-through system to evaluate the applicability of hepatic ethoxyresorufin O-deethylase (EROD) induction as an indicator of PAH exposure. PAH sources tested were coal-tar creosote (CTC), a low molecular weight fraction of creosote (LMWF), and a high molecular weight fraction of creosote (HMWF). A standard 96-h acute toxicity test was conducted to ensure that PAH concentrations tested in induction studies were sub-acutely toxic. The 96-h LC50 for spot was 1740 &\mu&g PAH/L (95% confidence interval = 1480-2060 &\mu&g PAH/L). The lowest concentration …


Vegetation Ecology Of Tidal Freshwater Swamps Of The Lower Chesapeake Bay, United States Of America, Richard D. Rheinhardt Jan 1991

Vegetation Ecology Of Tidal Freshwater Swamps Of The Lower Chesapeake Bay, United States Of America, Richard D. Rheinhardt

Dissertations, Theses, and Masters Projects

Woody and herbaceous vegetation were sampled in 23 tidal swamps along a tidal freshwater tributary of lower Chesapeake Bay. Four vegetative categories were ordinated with Detrended Correspondence Analysis (DECORANA). Species distribution patterns of each strata were compared with respect to edaphic factors, a wetness index, and mean water table depth. Woody species are restricted to hummocks (topographic highs). Hummocks drain as quickly as the tide drops and so are partially inundated for only short periods each day. Although low in canopy diversity, tidal swamps are floristically rich in herbaceous and woody understory species, ranking them among the most speciose in …


Modeling Sediment Resuspension In Lower Chesapeake Bay, Deborah L. Linden Jan 1991

Modeling Sediment Resuspension In Lower Chesapeake Bay, Deborah L. Linden

Dissertations, Theses, and Masters Projects

No abstract provided.


U(1) String Tension, Arthur F. Griesser Jan 1991

U(1) String Tension, Arthur F. Griesser

Dissertations, Theses, and Masters Projects

The long distance force between quarks in the U(1) approximation to quantum chromodynamics is calculated on a home made reduced instruction set computer optimized for that purpose. It is found that previous calculations were in error by as much as 85% due to contamination by the Coulomb interaction. The Coulomb constant, measured for the first time in this work, agrees with analytically obtained values.


The Relationship Of Habitat And Spatial Scale Upon The Developmental State And Settlement Of Blue Crab Postlarvae In Chesapeake Bay, Karen S. Metcalf Jan 1991

The Relationship Of Habitat And Spatial Scale Upon The Developmental State And Settlement Of Blue Crab Postlarvae In Chesapeake Bay, Karen S. Metcalf

Dissertations, Theses, and Masters Projects

No abstract provided.


Dielectric Monitoring Of The Chemical, Rheological, And Morphological Changes Incurred During Cure Of Epoxide-Amine Systems, Dara Elyn Levy Jan 1991

Dielectric Monitoring Of The Chemical, Rheological, And Morphological Changes Incurred During Cure Of Epoxide-Amine Systems, Dara Elyn Levy

Dissertations, Theses, and Masters Projects

No abstract provided.


The Investigation Of Organoboron Compounds And Organoboron/Nitrone Reactions, David Kent Hood Jan 1991

The Investigation Of Organoboron Compounds And Organoboron/Nitrone Reactions, David Kent Hood

Dissertations, Theses, and Masters Projects

No abstract provided.


Reactions Of Di-(1-Naphthyl) Diazomethane With Beta-Cyclodextrin, Margaret Frances Cabell Jan 1991

Reactions Of Di-(1-Naphthyl) Diazomethane With Beta-Cyclodextrin, Margaret Frances Cabell

Dissertations, Theses, and Masters Projects

No abstract provided.


Evaluation Of Scavenger Gases In A Helium Discharge Detector, Sandra Lynn Poteat Jan 1991

Evaluation Of Scavenger Gases In A Helium Discharge Detector, Sandra Lynn Poteat

Dissertations, Theses, and Masters Projects

No abstract provided.


Preparation And Characterization Of (E)-1-Alkenylboranes And(E)-1-Alkenylboronates An Investigation Of Borane/Nitrone Reactions, Philip Louis Smith Jan 1991

Preparation And Characterization Of (E)-1-Alkenylboranes And(E)-1-Alkenylboronates An Investigation Of Borane/Nitrone Reactions, Philip Louis Smith

Dissertations, Theses, and Masters Projects

No abstract provided.


The Effects Of The Exposure Of Atomic Oxygen On Polymeric Material: I Siloxane Modified Epoxy Resins Ii Polyetherimide Films With Additives, Eugene Canlas Aquino Jan 1991

The Effects Of The Exposure Of Atomic Oxygen On Polymeric Material: I Siloxane Modified Epoxy Resins Ii Polyetherimide Films With Additives, Eugene Canlas Aquino

Dissertations, Theses, and Masters Projects

No abstract provided.


Ecology Of Estuarine Fish Assemblages In Patos Lagoon, Brazil (32 Degrees S), And York River, Usa (37 Degrees N), With Review Of Zoogeography Of Fishes In Western Atlantic Warm-Temperate And Tropical Estuaries, Joao P. Vieira Jan 1991

Ecology Of Estuarine Fish Assemblages In Patos Lagoon, Brazil (32 Degrees S), And York River, Usa (37 Degrees N), With Review Of Zoogeography Of Fishes In Western Atlantic Warm-Temperate And Tropical Estuaries, Joao P. Vieira

Dissertations, Theses, and Masters Projects

The first two chapters of this study examine faunal composition and latitudinal patterns in diversity of fishes in warm-temperate and tropical estuarine waters of the western Atlantic from La Plata River (35&\sp\circ&S), Argentina, to Chesapeake Bay (37&\sp\circ&N), USA (33 faunal reports). Species distributions generally corresponded with previously recognized marine zoogeographic regions, and cluster analyses also showed that faunal similarity among estuarine sampling sites was related to the type of sampling gear used and to the type of habitat that was sampled in each estuary. The total number of fish species reported is positively related to the size of the area …


Contaminant Accumulation In Hard And Soft Shell Blue Crabs From An Urban Subestuary, Robert F. Mothershead Jan 1991

Contaminant Accumulation In Hard And Soft Shell Blue Crabs From An Urban Subestuary, Robert F. Mothershead

Dissertations, Theses, and Masters Projects

Muscle and hepatopancreas of blue crabs (Callinectes sapidus), collected from the Elizabeth River, Virginia, contained residues of polycyclic aromatic hydrocarbon (PAHs}, polychlorinated biphenyls (PCBs) and organochlorine pesticides. Analytical procedures involved dichloromethane extraction of lyophilized tissue, followed by molecular size and polarity-based purification of the extract. capillary gas chromatography with flame ionization detection and electrolytic conductivity detection was used for quantitation and tentative identification of the xenobiotic compounds. Mass spectrometry was used for confirmation of these identities. Contaminant concentrations were greater in hepatopancreas than in muscle in crabs from every site examined. Hepatopancreas PAH burdens were as high as 11 mg/kg …


Comparative Ecology, Morphology, And Population Genetics Of Black Triggerfish, Melichthys Niger, Kathryn D. Kavanagh Jan 1991

Comparative Ecology, Morphology, And Population Genetics Of Black Triggerfish, Melichthys Niger, Kathryn D. Kavanagh

Dissertations, Theses, and Masters Projects

No abstract provided.


Estimating Abundance And Annual Production Of Striped Bass Eggs With In Situ Silhouette Photography, John Douglas Field Jan 1991

Estimating Abundance And Annual Production Of Striped Bass Eggs With In Situ Silhouette Photography, John Douglas Field

Dissertations, Theses, and Masters Projects

No abstract provided.


Contrasts Between Tidal Freshwater And Estuarine Phytoplankton Growth On Intracellular And Recycled Nutrient Pools Over A Summer-Winter Seasonal Transition, Dean Douglas Kindler Jan 1991

Contrasts Between Tidal Freshwater And Estuarine Phytoplankton Growth On Intracellular And Recycled Nutrient Pools Over A Summer-Winter Seasonal Transition, Dean Douglas Kindler

Dissertations, Theses, and Masters Projects

No abstract provided.


Evaluation Of A Technique To Quantify Lipids In Bivalve Larvae Crassostrea Virginica Gmelin, Using Nile Red And Epiflourescence Microscopy, Laura Liliana Castell Perez Jan 1991

Evaluation Of A Technique To Quantify Lipids In Bivalve Larvae Crassostrea Virginica Gmelin, Using Nile Red And Epiflourescence Microscopy, Laura Liliana Castell Perez

Dissertations, Theses, and Masters Projects

No abstract provided.


Population Biology Of The Polychaete Loimia Medusa (Savigny) On A Tidal Sand Flat Of The York River, Chesapeake Bay, Rochelle D. Seitz Jan 1991

Population Biology Of The Polychaete Loimia Medusa (Savigny) On A Tidal Sand Flat Of The York River, Chesapeake Bay, Rochelle D. Seitz

Dissertations, Theses, and Masters Projects

No abstract provided.


Interactions Between Temperature And Tributlytin (Tbt) Toxicity To The Estuarine Mysid, Mysidopsis Bahia, Prentiss H. Balcom Jan 1991

Interactions Between Temperature And Tributlytin (Tbt) Toxicity To The Estuarine Mysid, Mysidopsis Bahia, Prentiss H. Balcom

Dissertations, Theses, and Masters Projects

No abstract provided.


Nutrient Standing Stocks And Partitioning In A Forested Coastal Plain Watershed: Groundwater, Stream And Marsh Creek, Sandra A. Hartenstine Jan 1991

Nutrient Standing Stocks And Partitioning In A Forested Coastal Plain Watershed: Groundwater, Stream And Marsh Creek, Sandra A. Hartenstine

Dissertations, Theses, and Masters Projects

No abstract provided.


Low-Energy Collisions Of Negative Ions With Atomic Hydrogen, Michael A. Huels Jan 1991

Low-Energy Collisions Of Negative Ions With Atomic Hydrogen, Michael A. Huels

Dissertations, Theses, and Masters Projects

Total cross sections for charge transfer and electron detachment for collisions of a variety of negative ions with atomic hydrogen have been separately determined for laboratory collision energies ranging from about 5 eV to 500 eV. The experiments are performed with an apparatus that utilizes a crossed-beam configuration with a radio-frequency discharge as the source of atomic hydrogen.;For collisions of H{dollar}\sp-{dollar}(D{dollar}\sp-{dollar}) with H the charge transfer cross sections increase monotonically with decreasing energy and display an isotope effect. at the lowest collision energies, the electron detachment cross sections are about one order of magnitude smaller than those for charge transfer; …


Nucleon Axial Vector Form Factors And Electromagnetic Transition Amplitudes In Perturbative Qcd, Jennifer L. Poor Jan 1991

Nucleon Axial Vector Form Factors And Electromagnetic Transition Amplitudes In Perturbative Qcd, Jennifer L. Poor

Dissertations, Theses, and Masters Projects

Values for the normal isovector axial vector form factor g$\sb{\rm A}$(Q$\sp2$) are calculated from the leading order perturbative QCD hard scattering amplitude and some previously reported models for the nucleon distribution amplitude, some of which have been derived from QCD sum rules. The values obtained from each of the distribution amplitudes gives a result that is consistent with the data extrapolated to high momentum transfer. The axial vector form factor is around one and one half times the proton's magnetic form factor in all the models which is also in accord with the data. We also calculate the isoscalar axial …


Error Flow In Computer Programs, Branson Wayne Murrill Jan 1991

Error Flow In Computer Programs, Branson Wayne Murrill

Dissertations, Theses, and Masters Projects

White box program analysis has been applied to program testing for some time, but this analysis is primarily grounded in program syntax, while errors arise from incorrect program semantics. We introduce a semantically-based technique called error flow analysis, which is used to investigate the behavior of a program at the level of data state transitions. Error flow analysis is based on a model of program execution as a composition of functions that each map a prior data state into a subsequent data state. According to the fault/failure model, failure occurs when a fault causes an infection in the data state …


Causal Reasoning About Distributed Programs, William Samuel Lloyd Jan 1991

Causal Reasoning About Distributed Programs, William Samuel Lloyd

Dissertations, Theses, and Masters Projects

We present an integrated approach to the specification, verification and testing of distributed programs. We show how "global" properties defined by transition axiom specifications can be interpreted as definitions of causal relationships between process states. We explain why reasoning about causal rather than global relationships yields a clearer picture of distributed processing.;We present a proof system for showing the partial correctness of CSP programs that places strict restrictions on assertions. It admits no global assertions. A process annotation may reference only local state. Glue predicates relate pairs of process states at points of interprocess communication. No assertion references auxiliary variables; …


Magnetic Field Strength Of Toroidal Plasma Equilibria, David Alan Garren Jan 1991

Magnetic Field Strength Of Toroidal Plasma Equilibria, David Alan Garren

Dissertations, Theses, and Masters Projects

The goal of nuclear fusion research is to confine a deuterium-tritium plasma at a sufficiently high temperature (15 keV) and density (3 $\times$ 10$\sp{20}$ m$\sp{-3}$) for a sufficient length of time (1 sec) to produce net fusion power. One means to attain the required plasma confinement is to embed the plasma within a magnetic field. The global structure of this magnetic field determines the variation of magnetic field strength within the surfaces of constant plasma pressure. This field strength variation in turn determines many of the stability and confinement properties of the plasma. This dissertation gives the first detailed exposition …