Physical Sciences and Mathematics Commons^™

Static And Ultrafast Moke Studies Of Exchange -Biased Cobalt Systems, Keoki A. Seu

Dissertations, Theses, and Masters Projects

We have studied the exchange bias interaction in metal bilayers IrMn/Co and FeMn/Co using the static and ultrafast pump-probe Kerr effects. Experiments conducted on wedged Co samples show that the exchange bias interaction is sensitive to the buffer layers grown beneath it when the antiferromagnetic layer is FeMn. The exchange bias strength, as measured by the shift in the magnetic hysteresis loop, follows a 1/tFM dependence as reported in the literature. The time-domain pump-probe experiments reveal coherent magnetization oscillations, whose frequencies are comparable to those measured by frequency-domain FMR measurements, and they fit well to FMR equations for the frequency. …

Uv Cure Kinetics Of Dimethacrylate Thin And Thick Samples, Yuemei Zhang

Dissertations, Theses, and Masters Projects

UV curing is using UV light as the energy source to induce the polymerization of liquid monomers and oligomers to form a solid polymer. Because UV polymerization is fast and energy-saving and a UV curable system has no VOC (volatile organic compound), this new technology has developed rapidly from thin film applications to thick sample applications. In addition, since the UV cure process can be controlled spatially and temporally, it also has an important application to make gradient materials with locally optimized properties. However, most research on UV cure is based on thin film applications, and the cure kinetics of …

The Effect Of Workload Dependence In Systems: Experimental Evaluation, Analytic Models, And Policy Development, Qi Zhang

Dissertations, Theses, and Masters Projects

This dissertation presents an analysis of performance effects of burstiness (formalized by the autocorrelation function) in multi-tiered systems via a 3-pronged approach, i.e., experimental measurements, analytic models, and policy development. This analysis considers (a) systems with finite buffers (e.g., systems with admission control that effectively operate as closed systems) and (b) systems with infinite buffers (i.e., systems that operate as open systems).;For multi-tiered systems with a finite buffer size, experimental measurements show that if autocorrelation exists in any of the tiers in a multi-tiered system, then autocorrelation propagates to all tiers of the system. The presence of autocorrelated flows in …

Carbon Nanosheets And Carbon Nanotubes By Rf Pecvd, Mingyao Zhu

Dissertations, Theses, and Masters Projects

A planar antenna RF plasma enhanced chemical vapor deposition apparatus was built for carbon nanostructure syntheses. When operated in inductive and capacitive plasma discharging modes, two carbon nanostructures, carbon nanotube (CNT) and carbon nanosheet (CNS), were synthesized, respectively.;A nanosphere lithography method was developed and used to prepare catalyst patterns for CNT growth. Using capacitively coupled C2H2/NH 3 plasma, randomly oriented CNT were synthesized on Ni dot patterned Si substrates. Aligned CNT arrays were grown on SiO2 coated Si substrates, using both C2H2/NH3 and CH 4/H2 capacitive plasmas.;When operated in inductive coupling mode, CNS were successfully deposited on a variety of …

Time-Resolved Magneto-Optical Imaging Of Superconducting Ybco Thin Films In The High-Frequency Ac Current Regime, Alexander Frey

Dissertations, Theses, and Masters Projects

No abstract provided.

Physical Processes Behind Delta Propagation And Flood Layer Dynamics, Po River, Italy, Aaron J. Bever

Dissertations, Theses, and Masters Projects

Rivers discharge around 20 billion tonnes of sediment to the coastal ocean each year (Milliman and Syvitski, 1992). Many supply dominated rivers possess large subareal and subaqueous deltas, whose growth depends on the physical processes controlling sediment deposition or removal. There has yet to be a complete understanding of how short term processes such as settling from buoyant plumes, wave/current resuspension, and transport by currents and gravity flows, interact to produce the depositional products that develop over varying timescales. The Po River in Northern Italy forms a substantial delta in the Adriatic Sea. It has five distributary mouths, and is …

Measurement Of Electroweak Asymmetries In Vector Electron Positron Scattering At 0.1 Less Than Q(2) Less Than 0.4 (Gev/C)(2), Jeffery A. Secrest

Dissertations, Theses, and Masters Projects

This work is based on the first engineering run of the G 0 experiment from October 2002 though January 2003 in Hall C at Jefferson Lab. The G0 experiment will be the first to measure the weak neutral form factors: GEZ( Q2), GMZ( Q2) and GAe( Q2) and to extract the proton's strange form factors: GEs(Q2) and GMs(Q 2) via a Rosenbluth separation over a range of Q 2 (0.1--1.0 (GeV/c)2). This will require four sets of measurements: forward angle measurements with a proton target, and three sets of backward angle measurements with a hydrogen and deuterium target. The measurements …

Sources And Composition Of Particulate Organic Matter In The Sacramento-San Joaquin River Delta, California, Vicki Pilon

Dissertations, Theses, and Masters Projects

Determining organic matter sources and their availability to higher organisms is essential to better understanding the link between organic matter (OM) dynamics and secondary production, particularly in highly-disturbed river-delta systems. The San Francisco Bay and its associated Delta, is one of the most modified aquatic systems, and is the focus of an ongoing restoration effort. Particulate organic matter (POM) and surficial sediments were collected in the Sacramento-San Joaquin River Delta, CA to document temporal and spatial variations in biochemical, (total protein, carbohydrate and lipid), lipid biomarker, and total hydrolysable amino acid (THAA) composition. Sources, composition and nutritional quality of OM …

Novel Derivatizing Agents For The Determination Of Methylmercury By Gas Chromatography Using Electron Capture Detection, Crystal Marie Irwin

Dissertations, Theses, and Masters Projects

No abstract provided.

Summary Tables: Caroline County, Virginia Shoreline Situation Report, Marcia Berman, Harry Berquist, Carl Hershner, Sharon A. Killeen, Karinna Nunez, Karen Reay, Tamia Rudnicky, 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).

Development Of The Maryland Shoreline Inventory Methods And Guidelines For Kent County, Marcia Berman, Harry Berquist, Sharon Killeen, Karinna Nunez, Karen Reay, Tamia Rudnicky, Daniel E. Schatt, David Weiss

Reports

No abstract provided.

Development Of The Maryland Shoreline Inventory Methods And Guidelines For Talbot County, Marcia Berman, Harry Berquist, Sharon Killeen, Karinna Nunez, Karen Reay, Tamia Rudnicky, Daniel E. Schatt, David Weiss

Reports

No abstract provided.

Dune Evolution Middlesex County, Virginia Rappahannock River And Piankatank River Shorelines, C. Scott Hardaway Jr., Donna A. Milligan, Lyle M. Varnell, Christine A. Wilcox, George R. Thomas, Kevin P. O'Brien

Reports

Shoreline evolution is the change in shore position through time. In fact, it is the material resistance of the coastal geologic underpinnings against the impinging hydrodynamic (and aerodynamic) forces. Along the shores of Chesapeake Bay, it is a process-response system. The processes at work include winds, waves, tides and currents, which shape and modify coastlines by eroding, transporting and depositing sediments. The shore line is commonly plotted and measured to provide a rate of change but it is as important to understand the geomorphic patterns of change. Shore analysis provides the basis to know how a particular coast has changed …

Dune Evolution Accomack County, Virginia Chesapeake Bay Shorelines, C. Scott Hardaway Jr., Donna A. Milligan, Lyle M. Varnell, Christine Wilcox, George R. Thomas

Reports

Shoreline evolution is the change in shore position through time. In fact, it is the material resistance of the coastal geologic underpinnings against the impinging hydrodynamic (and aerodynamic) forces. Along the shores of Chesapeake Bay, it is a process-response system. The processes at work include winds, waves, tides and currents, which shape and modify coastlines by eroding, transporting and depositing sediments. The shore line is commonly plotted and measured to provide a rate of change but it is as important to understand the geomorphic patterns of change. Shore analysis provides the basis to know how a particular coast has changed …

Dune Evolution Westmoreland County, Virginia Potomac River Shoreline, C. Scott Hardaway Jr., Donna A. Milligan, Lyle M. Varnell, Christine Wilcox, George R. Thomas, Kevin O'Brien

Reports

Shoreline evolution is the change in shore position through time. In fact, it is the material resistance of the coastal geologic underpinnings against the impinging hydrodynamic (and aerodynamic) forces. Along the shores of Chesapeake Bay, it is a process-response system. The processes at work include winds, waves, tides and currents, which shape and modify coastlines by eroding, transporting and depositing sediments. The shore line is commonly plotted and measured to provide a rate of change but it is as important to understand the geomorphic patterns of change. Shore analysis provides the basis to know how a particular coast has changed …

Center For Coastal Resources Management Annual Report 2005, Center For Coastal Resources Management

Reports

No abstract provided.

Development Of A Nontidal Inventory And Monitoring Strategy For Virginia – Phase I: Level I Statewide Inventory And Level Ii Coastal Plain Assessment., Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

No abstract provided.

Evaluation Of Striped Bass Stocks In Virginia : Monitoring And Tagging Studies, 2004-2008 Annual Report 1 September 2004 - 31 August 2005, Philip W. Sadler, John M. Hoenig, Robert E. Harris, B. Gail Holliman

Reports

This report presents the results of striped bass (Marone saxatilis) tagging and monitoring activities in Virginia during the period 1 September 2004 through 31 August 2005. It includes an assessment of the biological characteristics of striped bass taken from the 2005 spring spawning run, estimates of annual survival based on annual spring tagging, and the results of the fall 2004 directed mortality study that is a collaborative effort with the Maryland Department of Natural Resources. The information contained in this report is required by the Atlantic States Marine Fisheries Commission and is used to implement a coordinated management plan for …

The Photoelectric Effect In External Eields, Christian Bracher, John B. Delos, Vassiliki Kanellopoulos, Manfred Kleber, Tobias Kramer

Arts & Sciences Articles

Atoms and negative ions interacting with laser photons yield a coherent source of photoelectrons. Applying external fields to photoelectrons gives rise to interesting and valuable interference phenomena. We analyze the spatial distribution of the photocurrent using elementary quantum methods. The photoelectric effect is shown to be an interesting example for the use of coherent particle sources in quantum mechanics.

The Virginia Wetlands Report Vol. 20, No. 2, Virginia Institute Of Marine Science

Virginia Wetlands Reports

• VMRC Adopts Wetland Mitigation/Compensation Policy Changes. Tom Barnard
• Recommendations for Implementing the Tidal Wetlands Mitigation-Compensation Policy

A Study Of Dissolved Oxygen Impairment, North Branch Of Onancock Creek, Accomack County, Virginia, Virginia Institute Of Marine Science

Reports

No abstract provided.

Catlett-Burruss Research And Education Laboratory Dedication Ceremony, College Of William And Mary, Virginia Institute Of Marine Science, Chesapeake Bay National Estuarine Research Reserve In Virginia

Miscellaneous

Brochure for Dedication: Program of events celebrating the dedication of the Catlett-Burruss Research and Education Laboratory and honoring Dr. William Reay with the NOAA Environmental Hero Award.

Hyperpycnal Discharge Of Fluvial Sediment To The Ocean: Impact Of Super‐Typhoon Herb (1996) On Taiwanese Rivers, John D. Milliman, Shuh-Ji Kao

VIMS Articles

Hyperpycnal events (when suspended sediment concentrations exceed 40 g/L) occur in small‐ and medium‐sized rivers throughout the world but are particularly common in Taiwan; they are often related to landslides or debris flows initiated and transported by typhoon floods. Super‐Typhoon Herb, which swept across Taiwan on July 31–August 2, 1996, triggered floods and landslides throughout the southern part of the island. Sediment concentrations in at least seven rivers (Taan, Choshui, Pachang, Erhjen, Tsengwen, Kaoping, and Peinan) approached or exceeded 40 g/L. Calculated sediment discharged from nine rivers (these seven as well as the Wu and Houlung, neither of which apparently …

Estimating Relative Abundance Of Young Of Year American Eel, Anguilla Rostrata, In The Virginia Tributaries Of Chesapeake Bay (Spring 2004 Survey), Marcel M. Montane, Wendy A. Lowery, Hank Brooks, Aimee D. Halvorson

Reports

The Atlantic States Marine Fisheries Commission (ASMFC) adopted the Interstate Fishery Management Plan (hereafter referred to as FMP) for the American eel in November 4 1999. The FMP focuses on increasing coastal states’ efforts to collect American eel data through both fishery dependent and fishery independent studies. Consequently, member jurisdictions (including Virginia) agreed to implement an annual survey for young of year (YOY) American eels. The survey is intended to “…characterize trends in annual recruitment of the young of year eels over time [to produce a] qualitative appraisal of the annual recruitment of American eel to the U.S. Atlantic Coast” …

Effects Of Sunlight On Decomposition Of Estuarine Dissolved Organic C, N And P And Bacterial Metabolism, Sl Mccallister, Je Bauer, J Kelly, Hw Ducklow

VIMS Articles

The effects of natural sunlight and microbial decomposition on DOC, DON, and DOP were investigated along the salinity gradient of a temperate coastal plain estuary. The impact of sunlight-irradiated DOM on bacterial properties (bacterial abundance, production, bacterial growth efficiency [BGE]) was also followed. Surface-water light levels resulted in no detectable abiotic production of NH4+ or PO43- or loss of DOC. Bacterial decomposition of DOC was enhanced by 27 to 200 % in irradiated relative to dark treatments. There was, however, no corresponding enhancement in DON and DOP remineralization. Significant differences in bacterial decomposition of light-exposed DOC were frequently observed following …

The Crest, Summer 2005, Virginia Institute Of Marine Science

Reports

Table of Contents:

• Collaborative project gets to the bottom of oyster questions
• Rare crab may hold genetic secrets
• Shark trip brings research career full circle
• ICCAT adopts ban on "shark finning"
• Fisheries hires Fabrizio
• VIMS pair win Environmental Heroes Award
• Friedrichs and Steinberg receive faculty awards
• Trio tops citation analysis
• Fisheries partnership aids sturgeon restoration
• Researchers test beach-nourishment protocol
• CBNERR brings Bay education to local schools
• Hardaway selected to serve on national committee
• Emeritus Professor George Grant dies
• News Briefs

Radionuclide And Biomarker Proxies Of Past Ocean Circulation And Productivity In The Arabian Sea, A Pourmand, F Marcantonio, Ts Bianchi, Elizabeth A. Canuel, Ej Waterson

VIMS Articles

We present new excess Pa-231/Th-230 activity ratios and lipid biomarker results from northeastern Arabian Sea sediments (core 93KL) spanning the past 50 ka in an effort to constrain further the relationship between climate at low and high latitudes. Pa-231/Th-230 activity ratios are maintained at values significantly higher than the water-column production ratio of 0.093. Average Pa-231/Th-230 activity ratios are lower during the last glacial period than during the Holocene. The lowest Pa-231/Th-230 activity ratios coincide with the timing of Heinrich Events 1-5. Profiles of lipid biomarker fluxes and Pa-231/Th-230 activity ratios from 32 to 12 ka show similar patterns, suggesting …

Chesapeake Bay Dune Systems: Monitoring, Donna A. Milligan, C. Scott Hardaway Jr., George R. Thomas, Lyle M. Varnell, Thomas A. Barnard, William G. Reay, Travis R. Comer, Christine A. Wilcox

Reports

This project is aimed at developing an understanding of detailed beach and dune change. During the course of this monitoring, Hurricane Isabel impacted the coastal plain of Virginia and significantly altered almost all Bay shorelines to one degree or another in September 2003. This is particularly true of shorelines facing north, east, and south since the winds shifted as the storm passed. This event provided an opportunity to measure the changes to natural dune systems around the Bay due to the storm as well as their recovery after the event.

The Chesapeake Bay Breakwater Database Project Hurricane Isabel Impacts To Four Breakwater Systems, C. Scott Hardaway Jr., Donna A. Milligan, Christine A. Wilcox, Linda M. Meneghini, G. R. Thomas, Travis R. Comer

Reports

The Chesapeake Bay Breakwater Database is being developed by personnel in the Virginia Institute of Marine Science’s (VIMS) Shoreline Studies Program for the U.S. Army Corps of Engineers (COE) in order to:

1) document breakwater system performance around Chesapeake Bay relative to predictions

2) develop guidelines for breakwaters in sand limited and fetch limited systems such as estuaries, reservoirs, lakes and bays.

Interagency Shoreline Management Consensus Document, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

There are concerns in the general public and regulatory and environmental advisory agencies regarding the apparent inconsistent and /or contradictory guidance offered to property owners regarding shoreline management in Virginia. There has been a growing interest among the agencies that manage, or otherwise have a role in shoreline management, to develop a Virginia perspective on the issue. This project to develop a consensus position from a VIMS perspective, with funding from the Virginia Coastal Program, may serve as the initiation of an effort to develop consensus guidance on shoreline management that integrates the issues and concerns extant in the various …