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Articles 7171 - 7200 of 7254

Full-Text Articles in Physical Sciences and Mathematics

A Comparative Study Of A Salt Water Impoundment With Its Adjacent Tidal Creek Pertinent To Culture Of Crassostrea Virginica (Gmelin), William D. Anderson Iii Oct 1976

A Comparative Study Of A Salt Water Impoundment With Its Adjacent Tidal Creek Pertinent To Culture Of Crassostrea Virginica (Gmelin), William D. Anderson Iii

OES Theses and Dissertations

Certain physical, chemical and biological characteristics associated with the culture of subtidal Crassostrea virginica were assessed in a salt water impoundment and its adjacent tidal feeder creek. Large seed oysters (initial y = 57.3 mm) were transferred from a somewhat polluted estuary of Charleston Harbor to floating, mid-water, and bottom hardware cloth trays (200/tray) in a four hectare pond. Identical trays at comparable depths were placed in the tidal creek and each location was sampled monthly for growth and survival. Surface and bottom water samples were collected weekly throughout the study and hourly during four seasonal 25 hour stations. Standard …


Effect Of The Chesapeake-Elizabeth Sewage Outfall Virginia Beach, Virginia On The Distribution And Ecology Of Benthic Foraminifera, James M. Bates Jr. Oct 1976

Effect Of The Chesapeake-Elizabeth Sewage Outfall Virginia Beach, Virginia On The Distribution And Ecology Of Benthic Foraminifera, James M. Bates Jr.

OES Theses and Dissertations

Sediment and bottom water samples from seven stations at the Chesapeake Elizabeth sewage outfall, Virginia Beach, Virginia were collected in order to evaluate the effect of the outfall on benthic foraminifera. The top centimeter of sediment was analyzed for living and total (live plus dead) foraminiferal densities, chlorophyll a, sediment grain size, ATP, percentage of silt and clay, and total organic carbon. Bottom water salinity, temperature, and ammonia were also analyzed.

Living foraminiferal density increased from March to July and with distance from the outfall. Total foraminiferal density also increased from March to July. The set of environmental variables was …


Seasonal Distribution And The Retention Of Some Decapod Crustacean Larvae Within The Chesapeake Bay, Virginia, Joseph William Goy Oct 1976

Seasonal Distribution And The Retention Of Some Decapod Crustacean Larvae Within The Chesapeake Bay, Virginia, Joseph William Goy

OES Theses and Dissertations

Planktonic stages or 45 genera and species or decapod larvae were identified and staged from samples taken over a three year period in the lower portion and entrance area or Chesapeake Bay. The distribution of each larval stage of the decapod crustaceans found in the bay was determined and from this, the extent of the respective breeding season was deduced. In 1975, samples were taken monthly from stations along a transect at the baymouth, both at the surface and bottom. Two stations were also occupied over the tidal cycle in daylight and darkness. Evidence is presented that larvae of some …


Evaluation Of Upwelling Infrared Radiance In A Nonhomogeneous Nonequilibrium Atmosphere, Sundaresa Venkata Subramanian Oct 1976

Evaluation Of Upwelling Infrared Radiance In A Nonhomogeneous Nonequilibrium Atmosphere, Sundaresa Venkata Subramanian

Mechanical & Aerospace Engineering Theses & Dissertations

The primary purpose of this study was to investigate the influence of vibrational nonequilibrium upon upwelling infrared radiance from the earth's atmosphere. Basic equations are presented for calculating the atmospheric transmittance, heating rates, and equilibrium and nonequilibrium upwelling radiances. By employing the Lorentz line-by-line model for spectral absorption, heating rates and upwelling radiances were calculated for equilibrium as well ·as nonequilibrium conditions in the spectral range of 4.6 μ CO and 3.3 μ 'CH4 bands. For the spectral range of CO fundamental band, the influence of different 1~arameters on the upwelling radiance was also investigated. The results indicate that …


Stability And Local Effects Of An Offshore Sand Storage Mound, Dam Neck Disposal Site, Virginia Inner Continental Shelf, William Joslyn Saumsiegle Jul 1976

Stability And Local Effects Of An Offshore Sand Storage Mound, Dam Neck Disposal Site, Virginia Inner Continental Shelf, William Joslyn Saumsiegle

OES Theses and Dissertations

From 1967 to 1974 medium to coarse sand dredged from the Chesapeake Bay was stockpiled approximately three miles offshore of Dam Neck, Virginia in hopes that the sand could be recovered for local beach renourishment projects. The resulting mound was surveyed over a two year period to determine if the sand is being removed by wave and current action and if the creation of a new feature on the ocean bottom changes the wave refraction patterns and perhaps creates local erosion.

Bathymetric profiles across the storage mound show some apparent morphological changes, but a detailed analysis of this data is …


Topography, Shallow Structure, And Sedimentary Processes Of The Atlantic Continental Slope Off The Carolina Coast, Robert Michael Fitchko Jul 1976

Topography, Shallow Structure, And Sedimentary Processes Of The Atlantic Continental Slope Off The Carolina Coast, Robert Michael Fitchko

OES Theses and Dissertations

Analysis of 58 closely-spaced bathymetric and seismic profiles of the Carolina continental slope from the northern Blake Plateau to the vicinity of the North Carolina-Virginia state line (latitude 32• 30 'N to 36• 30 'N) indicates sharp contrasts in quantity of slumping and outcrop ledge continuity.

Terrestrial progradation and a relatively gentle slope characterize the area south of Cape Lookout, especially between Cape Romain and Cape Fear where sediment mantling is the greatest. Submarine canyons, slumps, and a steep slope are characteristic Between Cape Lookout and Cape Hatteras. North of Cape Hatteras, canyons and slumps are also common, though sediment …


The Effect Of 4-Chlororesorcinol On The Growth Potential Of Dunaliella Tertiolecta Butcher (Dun Clone), John Anthony Chigges Jul 1976

The Effect Of 4-Chlororesorcinol On The Growth Potential Of Dunaliella Tertiolecta Butcher (Dun Clone), John Anthony Chigges

OES Theses and Dissertations

Jolley (1973) identified and quantified 4-chlororesorcinol at the 1.2 μg/1 level in secondary treated sewage effluent as one of 17 stable organochlorine compounds. The present report presents the first data on the effect of 4-chlororesorcinol on the growth potential of the marine phytoplankter, Dunaliella tertiolecta Butcher (Dun clone).

The assay method used herein was that of the Marine Algal Assay Procedure: Bottle Test (EPA, 1974). An algal culture chamber was constructed capable of providing controlled temperature (18 ± 2°C) and light (400-500 ft-c) conditions. Four parameters were used to describe the growth response of D. tertiolecta including maximum specific growth …


Numerical Simulation Of Thermohaline Convection In The Mixed Layer Of The Ocean, Victor Eli Delnore Jul 1976

Numerical Simulation Of Thermohaline Convection In The Mixed Layer Of The Ocean, Victor Eli Delnore

OES Theses and Dissertations

The intradiumal heating and cooling cycle of the mixed layer of a tropical ocean is investigated through the use of a pseudo-two-dimensional numerical model. Particular emphasis is given to two-component diffusion resulting from dynamic instabilities in the water column. The conservation equations for salt and heat include the effects of solar heating, horizontal advectlon, and turbulent fluxes at the sea surface, while wind mixing enter through the use of depth-dependent eddy diffusion coefficients resulting from the wave-orbital shear model of KitaigorodsldLy. All inputs are treated as functions of time-of-day, or calculated via the bulk aerodynamic method.

The entrainment fluxes of …


Control Of Clay Mineral Distribution By Estuarine Circulation, James River Estuary, Virginia, Jean-Pierre Feuillet Apr 1976

Control Of Clay Mineral Distribution By Estuarine Circulation, James River Estuary, Virginia, Jean-Pierre Feuillet

OES Theses and Dissertations

A study was performed on the clay minerals of the James River estuary, Virginia, to determine the predominant factors that influence clay mineral distribution in the estuary. The factors of differential settling, flocculation, and diagenesis show minor or no effects on distribution, while estuarine circulation exerts the strongest influence upon the clay mineral distribution.

There are two clay suites in the James River estuary. The upper James River clay suite is a kaolinite, dioctahedral vermiculite, and mixed-layer suite, with kaolinite being the major mineral. The lower Chesapeake Bay clay suite is an illite, chlorite, and montmorillonite suite, with illite being …


Test Variation In The Sand Dollar, Mellita Quinquiesperforata (Leske), George Glynn Rountree Apr 1976

Test Variation In The Sand Dollar, Mellita Quinquiesperforata (Leske), George Glynn Rountree

OES Theses and Dissertations

Mellita quinguiesperforata is a common member of the benthos along the eastern coast of North America. This study considers variation of the test within the species, specifically: 1) variation in test weight, 2) variation in the length-width relationship, and 3) the average number of pore pairs in the ambulacral petals.

A total of 844 sand dollars from three localities was utilized: 1) Pass-a-Grill Beach, St. Petersburg, Florida,2) Bird Shoal, Beaufort, North Carolina, and 3) Fisherman Island, Virginia.

Animals were measured for length and width and the dry weight determined. Prediction equations for the size-weight relat1onships were computed for the three …


Dynamics And Sedimentology Of Inner Middle Ground - Nine Foot Shoal, Chesapeake Bay, Virginia, Mitchell Alan Granat Apr 1976

Dynamics And Sedimentology Of Inner Middle Ground - Nine Foot Shoal, Chesapeake Bay, Virginia, Mitchell Alan Granat

OES Theses and Dissertations

The historical, hydrodynamic, and sedimentological development of Inner Middle Ground - Nine Foot Shoal indicates that it is presently in quasi-equilibrium with mutually evasive ebb and flood tidal currents. Bathymetric comparisons among six surveys taken during the past 122 years depict development of the shoal from two linear sand bodies to its present double parabolic morphology. Circulation paths are proposed for each survey.

Information from eight current meter stations on and adjacent to Inner Middle Ground - Nine Foot Shoal were used to determine near-surface and near-bottom tidal current asymmetries and directions. The concepts of bathymetrically diverted currents and mutual …


A Numerical Model For The Prediction Of Tides And Tidal Currents In The Lafayette River, Norfolk, Virginia, G. Mcallister Sisson Apr 1976

A Numerical Model For The Prediction Of Tides And Tidal Currents In The Lafayette River, Norfolk, Virginia, G. Mcallister Sisson

OES Theses and Dissertations

A prediction technique for tidal heights and currents in the Lafayette River of Norfolk, Virginia has been formulated and tested by the implementation of a two-dimensional numerical model employing the Navier-Stokes momentum equations and conservation of mass. The model operates on a spatially-fixed rectangular grid system by utilizing a multi-operation finite difference scheme which employs implicit and explicit solutions to the aforementioned equations. Forces due to bottom friction and Coriolis are taken into account. The only open boundary considered in the model is the river mouth, across which tidal height is specified temporally. Collected tidal height and current data at …


The Natural History Of The Naked Goby Gobiosoma Bosci (Perciformes: Gobiidae), Leonard L. Nero Apr 1976

The Natural History Of The Naked Goby Gobiosoma Bosci (Perciformes: Gobiidae), Leonard L. Nero

OES Theses and Dissertations

The purpose of this study was to contribute to the knowledge of re ­ production, growth, age, abundance, habitat preference, feeding habit and behavior of the naked goby, Gobiosoma Bosci.

Monthly collections were made from January through December. 1974 in Deary Cove a apart of the Lynnhaven estuary, Virginia Beach, Virginia. All fish were measured and sexed in the field.

Most were returned to the population, the remainder. were removed for food habit analyses, determination of fecundity, degree of gonadal maturity and aging. Habitat­ preference and abundance were determined in the field.

Gobiosoma Bosci appears to be an annual …


An Efficient Dft Algorithm Using The Walsh Transform, Albert P. Gerheim Apr 1976

An Efficient Dft Algorithm Using The Walsh Transform, Albert P. Gerheim

Electrical & Computer Engineering Theses & Dissertations

The matrix transformation relating the sequency and frequency domains is derived. It is shown that these­ frequency-to-frequency conversion can be performed via a computationally efficient sparse matrix algorithm. The sequency-to-frequency algorithm can be used with a fast Hadamard transform to implement a discrete Fourier trans­ form. The efficiencies of this combined algorithm and a radix-two fast Fourier transform are compared.

The algorithm is applied to the sequency domain de­ sign of a Wiener digital filter. Improved computational efficiencies are achieved relative to the procedure de­veloped by Kahveci and Hall (9).


Methane Distribution And Production In The Georgia Salt Marsh, Larry P. Atkinson, John R. Hall Jan 1976

Methane Distribution And Production In The Georgia Salt Marsh, Larry P. Atkinson, John R. Hall

CCPO Publications

Bacterial action in the anaerobic sediments of Spartina salt marsh produce large quantities of methane. Water in contact with the marsh has methane concentrations 200-300 times normal oceanic concentrations. The methane content of the water varies from maximum of 1.2 mu l CH sub(4)/ super(l) super(-1) in the summer to a minimum of 0.005 mu l CHl1


An Engineering Solution To Improve Water Quality In A Tidal Lagoon, Richard Warren Price Oct 1975

An Engineering Solution To Improve Water Quality In A Tidal Lagoon, Richard Warren Price

Civil & Environmental Engineering Theses & Dissertations

Rising demand for better water quality stimulated research and development of ways to improve the quality level in existing as well as proposed water systems. At present, most of the solutions focus on biological and chemical processes.

Many natural or man-made water bodies act as receivers for both point and non-point pollution sources. Employment of biological and chemical treatment has proved successful in many of these cases; however, in some cases a more natural physical solution of an engineering mode would be more desirable. A "flushing" technique using the tidal fluctuation as a driving force has been investigated and the …


Application Of Satellite Data And Lars' Data Processing Techniques To Mapping Vegetation Of The Dismal Swamp, Jeffrey Allan Messmore Oct 1975

Application Of Satellite Data And Lars' Data Processing Techniques To Mapping Vegetation Of The Dismal Swamp, Jeffrey Allan Messmore

Biological Sciences Theses & Dissertations

This study concerned the feasibility of using digital satellite imagery and automatic data processing (ADP) techniques as a means of mapping swamp forest vegetation. Multispectral scanner data acquired by the Earth Resources Technology Satellite (ERTS-1; renamed LANDSAT-1) was analyzed using ADP techniques developed by Purdue University's Laboratory for Applications of Remote Sensing (LARS). The site for this investigation was the Dismal Swamp, a 210,000 acre swamp forest located south of Suffolk, Va. on the Virginia-North Carolina border. Two basic classification strategies were employed in determining the vegetation mapping capability of ERTS-1 data. The initial classification utilized unsupervised techniques which produced …


Sensitivity Of A Gas Filter Correlation Instrument To Variations In Atmospheric Profile And Earth Surface Temperatures, Joseph C. Casas Aug 1975

Sensitivity Of A Gas Filter Correlation Instrument To Variations In Atmospheric Profile And Earth Surface Temperatures, Joseph C. Casas

Physics Theses & Dissertations

The Gas Filter Correlation Radiometer Analyzer (GFCR), in application to the remote sensing of trace gases in the atmosphere, is potentially limited by the sensitivity of the measured upwelling thermal radiation to surface temperature and atmospheric temperature conditions. This study has been carried out to examine the principles of operation of the GFCR Analyzer and to obtain quantitative estimates of the errors produced in GFCR Analyzer measurements of CO (4.6μ), S02 (8.6μ), NH3 (11.0μ), and CH4 (8.1μ) resulting from uncertainties in the atmospheric temperature profile and ground temperature.

A simple mathematical prototype GFCR Analyzer was assumed. A line-by-line atmospheric radiative …


The Analysis Of Volatile Organic Compounds In The Southern Chesapeake Bay, Virginia By Gas Chromatography/Mass Spectrometry, James D. Haluska Jul 1975

The Analysis Of Volatile Organic Compounds In The Southern Chesapeake Bay, Virginia By Gas Chromatography/Mass Spectrometry, James D. Haluska

OES Theses and Dissertations

Sea-water samples from the Norfolk, Virginia area were analyzed for trace volatile organic compounds by helium sparging. Contents of the trap were injected into a gas chromatograph/mass spectrometer. Analysis of the trap contents indicated the presence of aliphatic and olef1nic hydrocarbons containing up to six carbon atoms and eight halogenated compounds of up to two carbon atoms in length. The halogenated compounds which were identified were dichlorofluoromethane, trichlorotrifluoroethane, carbon tetrachloride, chloroform, trichloroethane (2 isomers) bromodichloromethane, and chlorotrifluoroethylene. The

relative concentrations of volatile organic compounds generally tended to increase in samples collected from water prone to urban environmental pressures. All eight …


Microbenthic Algal Production Of An Intertidal Sandflat In Little Creek Harbor, Virginia Beach, Virginia, Clayton Barry Shedrow Jul 1975

Microbenthic Algal Production Of An Intertidal Sandflat In Little Creek Harbor, Virginia Beach, Virginia, Clayton Barry Shedrow

OES Theses and Dissertations

Estimated annual net microbenthic algal production of an intertidal sandflat on Little Creek Inlet, Virginia Beach, Virginia, was 105 g C/m2. Seasonally, primary production was greatest during the summer and fall periods (38 and 49 g C/m2, respectively). Productivity was found to vary directly with water temperature and standing crop of benthic diatoms, and inversely with incident solar radiation and standing crops of sedimentary chlorophyll 'a' and 'c'. Orthophosphate and nitrate-N appeared to be limiting factors, nitrate-N more so than orthophosphate. Mean annual net photosynthetic efficiency (based upon total light) for the microphytobenthic community was 0.09%. …


Processes Controlling The Distribution Of Methane In The Cariaco Tranch, Venezuela, Denis A. Wiesenburg Jul 1975

Processes Controlling The Distribution Of Methane In The Cariaco Tranch, Venezuela, Denis A. Wiesenburg

OES Theses and Dissertations

Abstract unavailable.


Genetic Studies Of Cave And Spring Populations Of The Freshwater Amphipod Crustacean Gammarus Minus Say, Steven Wolf Hetrick Jul 1975

Genetic Studies Of Cave And Spring Populations Of The Freshwater Amphipod Crustacean Gammarus Minus Say, Steven Wolf Hetrick

Biological Sciences Theses & Dissertations

The amphipod Gammaru. minus has three morphotypes in its Appalachian range : (1) a spring form with well-developed eyes, (2) an intermediate cave form with slightly reduced eyes, and (3) an extreme cave form with greatly reduced eyes. This study compares the genetic structure of populations in two karst areas and analyzes the genetics of populations of the three morphotypes.

Genetic data were collected from populations in the Ward's Cove, Virginia and Greenbrier Valley, West Virginia karst areas using zone electrophoresis zymograms. One hundred percent of the Ward's Cove populations are polymorphic at both MDH-1 and PEP 1 loci …


Urbanization And Environmental Change In Lynnhaven Estuary, Don W. Oswalt Jul 1975

Urbanization And Environmental Change In Lynnhaven Estuary, Don W. Oswalt

OES Theses and Dissertations

The very minimal amounts of available urbanization data demonstrate that the number of residential dwellings in the Lynnhaven drainage basin increased sharply in the late 1950’s and early 1960's, and that the 1970 basin population density value of 1981 people per square mile is larger than all the burrough density values, except for the Virginia Beach burrough. Due to a lack of data, only qualitative changes in Lynnhaven’s marine environment can be noted. There is a strong suggestion of an increase in amounts of urban storm water run-off into Lynnhaven since 1937. A considerable amount of siltation has occurred since …


The Synthesis Of New Maleimide Addition Polymer Precursors, Richard B. Brown Jul 1975

The Synthesis Of New Maleimide Addition Polymer Precursors, Richard B. Brown

Chemistry & Biochemistry Theses & Dissertations

1H-2,3-dimethylpyrrolo(1,2-a) benzimidazol-l-one (27) and 1H,9H- 2,3,7,8-tetramethyl-bispyrrolo(1,2-a:6,7-a')benzodiimidazo1-1,9-dione (32) have been synthesized from dimethylmaleic anhydride and o-phenylenediamine and 1,2,4,5-tetraaminobenzene, respectively. The presence of reactive olefinic double bonds in the synthesized compounds was of interest as a site for possible addition polymerization.

The synthetic route involved, in both cases, a simple nucleophilic substitution reaction between the diamine(or tetraamine) and the anhydride to form an intermediate amide-acid-amine which rapidly cyclized to the imide amine. The final ring closure required more rigorous conditions and occurred at melt reaction temperatures.


Heavy Mineral Distribution In The Lower Chesapeake Bay, Virginia, Frances Firek Apr 1975

Heavy Mineral Distribution In The Lower Chesapeake Bay, Virginia, Frances Firek

OES Theses and Dissertations

Heavy minerals from 195 bottom sediment samples of the lower Chesapeake Bay, Virginia have been studied. In comparison with other areas such as the Gulf of Mexico, qualitative and qualitative mineralogical variations were subdued, because of the absence of widely divergent source areas. The effect of present-day drainage system on the mineralogical distribution patterns is not clear, largely because of the complex Pleistocene history of the study area.

Seven geographic provinces were defined and treated statistically. An analysis of variance was conducted on the seven provinces. The more significant mineral species from the study area are zircon, hornblende, pyroxene, and …


77-4 Hydrographic And Biological Observations At An Anchor Station Off St. Augustine, Florida (Eastward Cruise E-1g-75), Larry P. Atkinson, Gustav A. Paffenhofer, William M. Dunstan Jan 1975

77-4 Hydrographic And Biological Observations At An Anchor Station Off St. Augustine, Florida (Eastward Cruise E-1g-75), Larry P. Atkinson, Gustav A. Paffenhofer, William M. Dunstan

CCPO Publications

The intrusion of deep, nutrient-rich Gulf Stream water into the shelf waters off the southeastern United States is probably the major source of nutrients in the shelf waters and consequently intrusions have a major impact on the biota. This particular cruise was one of the first to be designed to find the front that represents the interface between intruding Gulf Stream waters and normal shelf water. Once the front was delineated an anchor station was occupied to observe the time change at a particular location as the front moved back and forth past the station.

The methods used and resultant …


Quantitative And Qualitative Seasonal Analysis Of The Surface Zooplankton Of Magothy Bay, Virginia, Malcom E. Browne Oct 1974

Quantitative And Qualitative Seasonal Analysis Of The Surface Zooplankton Of Magothy Bay, Virginia, Malcom E. Browne

OES Theses and Dissertations

No abstract provided.


The Thermal And Photolytic Rearrangements Of Isatoic Acid Diazide, Ana Alejandre Ciereszko Oct 1974

The Thermal And Photolytic Rearrangements Of Isatoic Acid Diazide, Ana Alejandre Ciereszko

Chemistry & Biochemistry Theses & Dissertations

The primary objective of this research has been the thermolysis and photolysis of isatoic acid diazide 1. Thermolysis in low boiling solvents produced the acylazido benzimidazolone 10, while refluxing in high boiling solvents gave rise to the imidazoindazoline 31, presumably via Curtius rearrangements.

Photolysis of the diazide in methylene chloride gave rise to two photo products, 10 and 31, while photolysis in tetrahydrofuran produced only 31.

A study of the spectral and chemical characteristics of these products have been carried out.


The Synthesis And Characterization Of The 2,2'-Bisacylazide Of 2,2'-Diphenyldicarboxylic Acid, Subrata Chatterjee Jul 1974

The Synthesis And Characterization Of The 2,2'-Bisacylazide Of 2,2'-Diphenyldicarboxylic Acid, Subrata Chatterjee

Chemistry & Biochemistry Theses & Dissertations

The primary objective of this investigation w2s the photolytic and thermal characterization of a newly synthesized aromatic diacylazide, the 2,2'-bisacylazide~ of 2,2'-diphenyldicarboxylic acid 19. Photolysis of the azide in acetone ~ave rise to a mixture of photoproducts, one of which is a known system, 6(5-H)-phenanthridionone 28, while photolysis of 19 in ethanol gave ris,2 to the corresponding hydroxamic acid ester 40.


Feeding And Food Preferences By Three Sympatric Species Of Cyprinodontid Fishes, Lawrence J. Baer Jul 1974

Feeding And Food Preferences By Three Sympatric Species Of Cyprinodontid Fishes, Lawrence J. Baer

OES Theses and Dissertations

The feeding and food utilization by three sympatric species of cyprinodontid fishes was examined using a modified Ivlev Electivity Co-efficient. Results indicated that although Fundulus heteroalitus and Fundulus majalis are sympatric in the area examined,their usage of the available food source varied noticeably. The third investigated species, Cyprinodon variegatus, fed mainly upon a vegetal detritus food source varied by the consumption of invertebrate and vertebrate food items. Slight intra-specific variances of diet between crespuscular periods was also discussed.