Physical Sciences and Mathematics Commons^™

Morphologic Time Series From A Submarine Sand Ridge On The South Virginia Coast, John F. Mchone Jr.

OES Theses and Dissertations

Submarine sand ridges several km long locally merge southward into the U. S. Atlantic coastline. Shallow (< 8m) observations of -such a ridge at False Cape, Virginia, favor a modern hydraulic origin. Time series maps show the ridge to be paralleled by a landward trough of approximately equal volume. Ridge flanks are usually steeper on the trough side.

Northeasterly winds and waves generate a coast-parallel current which funnels southward into the trough scouring it out and providing sediments for ridge aggradation. The current may be organized as a helical flow cell or cells. Bottom currents converge southward along the ridge crest causing landward transport of traction load along the crest. The trough current eventually breaches the confining ridge at the head of the trough, cutting saddles with steeper seaward slopes and producing outlying sediment fans.

The ridge and trough rest obliquely …

Phytoplankton Distribution In Waters Off The Northeastern Coast Of The United States, Sharon H. Craft

Biological Sciences Theses & Dissertations

Abstract unavailable.

Surface Water Turbidity In The Entrance To Chesapeake Bay, Virginia, James R. Melchor

OES Theses and Dissertations

Seasonal and spatial variations in the surface water turbidity across the entrance to Chesapeake Bay, Virginia, have been monitored with an optical transmissometer for one year. The data indicate a suspended-sediment gradient across the entrance with higher turbidity on the south side. This condition suggests that the flooding and ebbing tidal currents are influenced by Coriolis force. Clearer ocean water is introduced into the bay on the north side; whereas highly turbid water from the major drainage systems exits on the south side. A salinity gradient with18 0/00 on the south side of the bay and approximately 32 0/00 on …

The Synthesis And Characterization Of The 2,2'-Bisacylazide Of 3,3'-Bipyridine, Magdy Adly Guirguis El-Fayoumy

Chemistry & Biochemistry Theses & Dissertations

The primary objective of this research has been the synthesis and characterization of a new heterocyclic diacylazide, the 2,2'-bisacylazide of 3,3'-bipyridine 19. This heterocyclic diacylazide has been successfully synthesized from the phenanthrolin-5,6-dione 14, and examined with regard to its.thermal and photolytic decomposition.

Thermal decomposition of this disacylazide seems to go by a double-barreled Curtius rearrangement leading to a series of pyridonaphthyridinone (20) compounds such as 22 and 29.

An initial study of the photolysis of this bisacylazide has been initiated to examine the possible formation of nitrene-type intermediates.

Determination Of Nutrient Levels And Proposed Predictive Models For Phosphate In The Lafayette River, Norfolk, Virginia, John R. Montgomery

OES Theses and Dissertations

The Lafayette River, an Urban, well-mixed estuarine embayment, was sampled from October, 1970 to January, 1972 for phosphate, nitrate, nitrite, oxygen, water temperature and salinity. The mean values found for these samples were: oxygen saturation from 69% to 106% nitrate from 0 to 4 microgram-atoms per liter, and salinity from 13 ‰ to 24 ‰. The mouth of the Elizabeth River to Hampton Roads as also sampled from May, 1971 to August, 1971. The Lafayette and Elizabeth Rivers were also sampled over a 24 hour period in the summer of 1971 and the Lafayette River again in the winter of …

A Physical Hydrographic Study Of The Lafayette River, E. Glenn White

OES Theses and Dissertations

A basic investigation of the physical ~properties, temperature, density and current velocity, in the Lafayette River is presented. Graphs of the observations indicata a difference in salinity, density and current velocity- distributions after moderate to heavy rains from the graphs during a dry period. The changes in distribution indicate a change in the classification of the estuary from a type B/C, partially mixed estuary, to a type D, sectionally homogeneous estuary. The estuary is predominantly a well-mixed or sectionally homogeneous estuary.

Changes in salinity, temperature, density and current velocity over tidal cycles are discussed as well as tidal height data. …

The Influence Of The Summer Thermocline On Estuarine Classification In The Chesapeake Bay Entrance, William G. Weiss Jr.

OES Theses and Dissertations

The temperature, salinity, and sigma-t of 397 oceanographic stations taken in the entrance to Chesapeake Bay were plotted using a simple interpolation formula by the lBM 1130 computer. Each station was catalogued by position, tidal stage, season, and estuarine classification. Results indicated increased stratification during the ebb phase of all entrance stations regardless of season. Partially mixed conditions predominate. The influence of the summer thermocline on the stratification caused a slight increase in the summer stratification mean. However, statistical tests showed this summer increase to be insignificant at the 95% level. Detailed classification of tidal stage by estuarine type for …

An Evaluation Of A Stable Isotope Of Dysprosium For Labeling And Tracing Sedimentary Particles, Charles Glenn Boone

OES Theses and Dissertations

An evaluation of the application of dysprosium oxide as a tracer coating to surface label sedimentary particles is made. Physical and chemical properties of the labeled sand are studied. Effective diameters and settling properties of the tracer sand are compared with unlabeled sand. A total of 8.51 kg of labeled sand was placed on the beach at Camp Pendleton. Dispersal patterns obtained 1 and 4 hours after tracer injection indicate a general down current mean tracer migration rate of 0.21 cm/sec (0.42ft/sec). An absolute detection limit of 4 or 5 parts per 100,000 and a real detection limit, after field …

An Application Of Spectroscopic Techniques To The Measurement Of Electron Density And Temperature In A Brush Cathode Plasma, Ramabhai M. Patel

Physics Theses & Dissertations

A brief review of the Langmuir probe, microwave and spectroscopic techniques most commonly used to make measurements .of plasma electron temperature and density is presented. Of these various methods, certain spectroscopic methods are applied to the measurements of electron density and temperature in a helium brush cathode plasma. The density measurement is based on the manner in which a series of Stark broadened spectral lines merges into an apparent continuum before the normal series limit is reached. This approach met with only limited success in that the density could be determined only by extrapolating the data obtained. Primarily because of …

A Graphic Analysis Of Current Velocity Salinity Density And Temperature During Periods Of Ebb And Flood In The Entrance To Thimble Shoals Channel, Stanley Hecker

OES Theses and Dissertations

A graphic analysis is presented of the observed patterns of longitudinal current velocity, salinity, density and temperature through a group of tidal cycles in Thimble Shoals Channel. Graphs of the properties indicate that this estuary passes through a sequence of estuarine types during a tidal cycle. In spite of this observation, the net non-tidal profiles of salinity are patterns of a partially mixed estuary.

The most noteworthy observation in this study was that longitudinal velocity was essentially constant throughout the water column at any increment of a tidal cycle as well as in the net non-tidal profile of the water …

Phytoplankton Composition At Lake Drummond In The Dismal Swamp, Virginia, William Howard Poore Jr.

Biological Sciences Theses & Dissertations

Abstract unavailable.

Observations On The Hydraulic Regime Of The Ridge And Swale Topography Of The Inner Virginia Shelf, Barry W. Holliday

OES Theses and Dissertations

The Virginia inner shelf is dominated by southwest-trending sand ridges. Wavelengths are 2 to 4 km; amplitudes are up to 10 m; crests can be traced for up to 10 cm, Nearshore ridges trend southwest into the shore face and merge with it at depths as shoal as 5 m. The ridges have been examined by bathymetric mapping, grab sampling, coring, seismic profiling, SCUBA diving, and current monitoring. They are hemi-cylindrical sand bodies of recent age, resting on a pre-recent substrate. In troughs a thin, medium- to coarse-gained, pebbly lag veneers the substrate. Crests consist of a better sorted, medium- …

Analysis Of Littoral Transport By Wave Energy: Cape Henry, Virginia To The Virginia, North Carolina Border, Zvi Henry Weinman

OES Theses and Dissertations

An investigation of the rate of littoral transport by an analysis of wave energy for the area from Cape Henry, Virginia to the Virginia, North Carolina border is made. Wave refraction diagrams are done by digital computer. Total upcoast (northerly) transport is determined to be 2.05 x 10⁶ yds³/year. Total downcoast (southerly) transport is determined to be 1.07 x 10⁶ yds³/year. Net transport is determined to be 9.8 x 10⁵ yds³/year in an upcoast (northerly) direction. The values obtained are compared with those of similar areas. The general efficacy of the …

Spectroscopic Measurement Of The Electron Temperature In The Tenuous Argon Ion Laser Plasma, Dane Danijel Bicanic

Physics Theses & Dissertations

The validity of the line intensity ratio technique for measuring the electron temperature was examined for an argon plasma with a "population inversion" i.e., the number of ions with electrons in the upper 4p levels was greater than in the lower 4s levels. The line intensities from these levels, the argon ion lasing transitions, were measured in a pulsed tenuous plasma at 110μ Hg produced by discharging a capacitor through a tube 2m long and 7mm inside diameter. The electron impact cross sections for simultaneous excitation and ionization as measured by Latimer and St. John were used and averaged over …

An Evaluation Of An Electromagnetic Current Meter For Study Of Water Particle Motion, George Milton Hecker

OES Theses and Dissertations

A new sophisticated electromagnetic current meter was laboratory and field tested in a wide variety of applications, ranging from measurement of net bottom currents (primarily tidal origin) on the continental shelf, to horizontal and vertical components of wave induced orbital motion of waves with periods as small as one second.

These tests indicate that this instrument is capable of performing to at least the following specifications, subject to the comments which follow:

Speed range: Accuracy: Threshold: 0 to + 5 knots + 0.2 knots + 0.02 knots Response time: 0.25 sec. Direction: -+ 7 degrees Depth: '0 to 42 feet …

Grain Size Reconnaissance Of The Virginia-North Carolina Inner Shelf Analysis By Settling Technique, Robert Bailey Sanford Jr.

OES Theses and Dissertations

The 2-fold purpose of this study is to calibrate a Rapid Sediment Analyzer and to use it to aid in the determination of the genesis of sediment on the inner continental shelf between Cape Henry and Cape Hatteras. Rapid Sediment Analyzer calibration was conducted by comparison of sieving and settling results of similar sands.

The study area was divided into sediment provinces by both a qualitative procedure (grain size and topography) and a quantitatively procedure (factor-vector analysis). Qualitative provinces are beach and surf, upper shore face, lower shore face, sea floor, and terminal shoals. The berm fines from each terminal …

Erasure Of Sediment Surface Features By Mellita Quinquiesperforata (Leske), Walter Richard Boehmer

OES Theses and Dissertations

Erasure of sediment surface features by individuals of the species, Mellita guinguiesperforata, observed in this study suggests that all members of the sub-order, Scutellina, are able to erase sediment surface features. Sweep time, the time needed to erase the surface features of an area, depends on the population density, individual size, and speed of movement of the sand dollars. Assuming their pattern of movement as random, the following equation can be used to determine sand dollar sweep time,

T - 3.2 N^-0.76 (W / S) (A/ W² )^1.21

where T is sweep time, N is the …

An Investigation Of A Gas Measurement Technique Employing Ultraviolet Excitation, Alphonso Vincent Diaz

Physics Theses & Dissertations

A study was undertaken to determine the general applicability of a temperature measurement technique which uses the fluorescence stimulated by a vacuum ultraviolet continuum as the indicator. This study was directed toward determining the temperature of nonradiating carbon monoxide. A number of ultraviolet radiation sources which produced high intensity in the region of l,150 A were investigated. This study led to the conclusion that the technique was not applicable to measurements in carbon monoxide within the present limits of' detectability.

Excitation Of Hydrogen Atoms By Fast Protons, Edward Ellis Fitchard

Physics Theses & Dissertations

In this thesis a theoretical study is made of excitation of hydrogenic atom by charged particles such as protons or electrons. The approximation to the cross section for an inelastic scattering process is obtained under the following radically simplifying assumptions. The projectile is represented in its initial and final state by plane waves. All distortions are neglected whether they originate in an inelastic process or an elastic deflections of the charged particle by the nucleus. The perturbation of the atomic orbits between which the projectile induces transitions is neglected. Nonrelativistic hydrogenic wave functions are used for the electronic states. In …

Population Excitation Mechanism Of The First Negative System Of Nitrogen, Robert Lynn Bridigum

Physics Theses & Dissertations

The photoionization process of nitrogen was studied using the helium resonance line (584 Å) to excite nitrogen from the ground state to an excited ionic state. The transitions from the second excited state of the ion, N+2B²Σt+u to the ground state of the ion, N+2X²Σ+g, were of particular interest. The nitrogen fluorescence was spectrally analyzed in the region from 2000 Å to 5000 Å , to determine the most prominent bands of the first negative system. Two unresolved bands were observed: the v = 0 to v =.O band at 3914 Å, and the …