Physical Sciences and Mathematics Commons^™

Elizabeth River Tributyltin Monitoring Program 1999-2006 : A Report To The Virginia Department Of Environmental Quality Tidewater Regional Office, Michael A. Unger

Reports

The purpose of this project was to implement a study in 1999/2000 that would document the current levels of tributyltin (TBT) in the Elizabeth River and provide baseline data for future efforts to determine the trend of TBT concentrations found in the Elizabeth River Watershed. Subsequent years of sampling have documented spatial and temporal trends in TBT and are described in this report.

Summary Tables: Westmoreland County, Virginia Shoreline Situation Report, Marcia Berman, Harry Berquist, Carl Hershner, Sharon Killeen, Karinna Nunez, Tamia Rudnicky, Daniel E. Schatt, David Weiss

Reports

The Shoreline Inventory Summary Tables quantify observed conditions based on river systems, such as the combined length of linear features (e.g. shoreline miles surveyed, miles of bulkhead and revetment), the total number of point features (e.g. docks, boathouses, boat ramps) & total acres of polygon features (tidal marshes).

Magnetization Dynamics And Anisotropy In Ferromagnetic/Antiferromagnetic Ni/Nio Bilayers, Andreas Petersen

Dissertations, Theses, and Masters Projects

No abstract provided.

Parallel Generalized Delaunay Mesh Refinement, Andrey Nikolayevich Chernikov

Dissertations, Theses, and Masters Projects

The modeling of physical phenomena in computational fracture mechanics, computational fluid dynamics and other fields is based on solving systems of partial differential equations (PDEs). When PDEs are defined over geometrically complex domains, they often do not admit closed form solutions. In such cases, they are solved approximately using discretizations of domains into simple elements like triangles and quadrilaterals in two dimensions (2D), and tetrahedra and hexahedra in three dimensions (3D). These discretizations are called finite element meshes. Many applications, for example, real-time computer assisted surgery, or crack propagation from fracture mechanics, impose time and/or mesh size constraints that cannot …

7,8-Dichloro-1,2,3,4-Tetra­Hydro­Phenazine, Cesar H. Zambrano, Robert D. Pike, Ricky J. Paul Gibson, Brittnay D. Barger, Eric E. Dueno

Arts & Sciences Articles

In the structure of the title compound, C12H10Cl2N2, the cyclo­hexene ring adopts a half-chair conformation.

Assessing The Impacts Of Land Use Change On Hard Clam Aquaculture In Old Plantation Creek, Northampton County, Virginia, Matthew J. Strickler

Dissertations, Theses, and Masters Projects

One of the main threats to water quality in the Chesapeake Bay is contamination by bacterial loading from point and non-point sources. While only very high levels of fecal bacteria (greater than 200 MPN/100ml) indicate the potential of a health threat to humans from contact with water, lower concentrations (14 MPN/100 ml) make the shellfish from contaminated waters unfit for human consumption. Many nearshore areas that are vulnerable to bacterial contamination also are suitable for the propagation of shellfish, including the hard clam (Mercenaria mercenaria). This is especially true on Virginia’s Eastern Shore, where shallow, sheltered waters with optimal salinity …

The Role Of Bacteria-Particle Interactions In Marine Snow Dynamics, Emily M. Yam

Dissertations, Theses, and Masters Projects

Marine snow aggregates are one of the primary vehicles for deep-sea carbon sequestration. Bacterial activity on marine snow affects both degradation and aggregation processes that determine the flux of carbon to depth, biogeochemical cycling, and microbial food webs. The microscale processes occurring on aggregates depend on specific interactions between bacteria and particles. In this thesis, I describe two such interactions which have larger scale implications on marine snow dynamics: (1) the effects of starvation on bacterial motility and colonization behaviors on marine aggregates and (2) interactions between bacteria and phytoplankton which could contribute to the production of TEP.

Current models …

The Impact Of Drainage Ditches On Salt Marsh Flow Patterns, Sedimentation And Morphology: Rowley River, Massachusetts, Lynsey E. Lemay

Dissertations, Theses, and Masters Projects

Salt marshes along many tidal systems in New England have been ditched since colonial times. These ditches have been thought to help control mosquito populations and increase salt marsh hay production by improving water drainage from the marsh. Although these ditches are prominent geomorphic features, little quantitative work has focused on how these man-made ditches may alter marsh hydrology and geomorphology. This study attempts to quantify the ways in which ditches alter sediment and water transport pathways and how that affects the overall morphology and surface geology. This study also addresses treatment affects on sedimentation from fertilization and fish removal …

Elemental And Isotopic Characterization Of Organic Matter And Carbon In The U.S South Atlantic Bight, Jennifer A. Dealteris

Dissertations, Theses, and Masters Projects

No abstract provided.

1,2,3,4-Tetra­Hydro­Quinoxaline, Robert D. Pike, Emily C. Dugan

Arts & Sciences Articles

The title compound, C8H10N2, was synthesized from the hydrogenation reaction of quinoxaline. The crystal structure reveals a puckered piperazine ring fused to a planar aromatic ring. A series of N-HN hydrogen bonds produces an infinite zigzag chain.

Fluorescence Imaging Study Of Free And Impinging Supersonic Jets: Jet Structure And Turbulent Transition, Jennifer Ann Inman

Dissertations, Theses, and Masters Projects

A series of experiments into the behavior of underexpanded jet flows has been conducted at NASA Langley Research Center. This work was conducted in support of the Return to Flight effort following the loss of the Columbia. The tests involved simulating flow through a hypothetical breach in the leading edge of the Space Shuttle Orbiter along its reentry trajectory, with the goal of generating a data set with which other researchers can test and validate computational modeling tools. Two nozzles supplied with high-pressure gas were used to generate axisymmetric underexpanded jets exhausting into a low-pressure chamber. These nozzles had exit …

Decoupling Method For Parallel Delaunay Two-Dimensional Mesh Generation, Leonidas Linardakis

Dissertations, Theses, and Masters Projects

Parallel mesh generation procedures that are based on geometric domain decompositions require the permanent separators to be of good quality (in terms of their angles and length), in order to maintain the mesh quality. The Medial Axis Domain Decomposition, an innovative geometric domain decomposition procedure that addresses this problem, is introduced. The Medial Axis domain decomposition is of high quality in terms of the formed angles, and provides separators of small size, and also good work-load balance. It presents for the first time a decomposition method suitable for parallel meshing procedures that are based on geometric domain decompositions.;The Decoupling Method …

Inactive Sulfide Mounds Of The Manus Basin: Invertebrate Composition And Potential For A Chemoautotrophic Food Web, Kristin Lynn Erickson

Dissertations, Theses, and Masters Projects

No abstract provided.

Effects Of Mercury On Condition And Coloration Of Belted Kingfishers, Ariel Elizabeth White

Dissertations, Theses, and Masters Projects

No abstract provided.

Forward Secure Fuzzy Extractors, David Goldenberg

Dissertations, Theses, and Masters Projects

No abstract provided.

Tweakable Blockciphers Secure Against Generic Exponential Attacks, Elizabeth Ann Crump

Dissertations, Theses, and Masters Projects

No abstract provided.