Physical Sciences and Mathematics Commons^™

Damping Of Turbulence By Suspended Sediment: Ramifications Of Under-Saturated, Critically-Saturated, And Over-Saturated Conditions, Carl T. Friedrichs

Presentations

No abstract provided.

Carbonyl-Twisted 6-Acyl-2-Dialkylaminonaphthalenes As Solvent Acidity Sensors, Amy M. Green, Hannah R. Naughton, Zachariah B. Nealy, Robert D. Pike, Christopher J. Abelt

Arts & Sciences Articles

Derivatives of 2-propionyl-6-dimethylaminonaphthalene (PRODAN) with twisted carbonyl groups were investigated as highly responsive sensors of H-bond donating ability. The PRODAN derivative bearing a pivaloyl group (4) was prepared. The torsion angle between the carbonyl and naphthalene is 26° in the crystal. It shows solvatochromism that is similar to five other PRODAN derivatives (1–3, 5, 6). Twisted-carbonyl derivatives 3, 4, and 6 show strong fluorescence quenching in protic solvents. The order of magnitude of the quenching is linearly related to the H-bond donating ability of the solvent (SA) but not to other solvent properties. Binary mixtures of protic solvents show specific …

Bis(Tetra­Ethyl­Ammonium) Oxalate Dihydrate, Timothy J. Mcneese, Robert D. Pike

Arts & Sciences Articles

The title compound, 2C8H20N+ C2O4 22H2O, synthesized by neutralizing H2C2O42H2O with (C2H5)4NOH in a 1:2 molar ratio, is a deliquescent solid. The oxalate ion is nonplanar, with a dihedral angle between carboxylate groups of 64.37 (2). O—HO hydrogen bonds of moderate strength link the O atoms of the water molecules and the oxalate ions into rings parallel to the c axis. The rings exhibit the graph-set motif R4 4 (12). In addition, there are weak C—HO interactions in the crystal structure.

Universal Conductance Fluctuations In Dirac Materials In The Presence Of Long-Range Disorder, Enrico Rossi, J. H. Bardarson, M. S. Fuhrer, S. Das Sarma

Arts & Sciences Articles

We study quantum transport in Dirac materials with a single fermionic Dirac cone (strong topological insulators and graphene in the absence of intervalley coupling) in the presence of non-Gaussian long-range disorder. We show, by directly calculating numerically the conductance fluctuations, that in the limit of very large system size and disorder strength, quantum transport becomes universal. However, a systematic deviation away from universality is obtained for realistic system parameters. By comparing our results to existing experimental data on 1/f noise, we suggest that many of the graphene samples studied to date are in a nonuniversal crossover regime of conductance fluctuations.

Structure And Bonding In Copper(I) Carbonyl And Cyanide Complexes, Robert D. Pike

Arts & Sciences Articles

The coordination chemistry of copper(I) carbonyls and cyano complexes is reviewed. Primary attention is focused on structural chemistry, including coordination behavior, bridging modes, network formation, flexible coordination number, and reversible ligand binding. Additional coverage of infrared spectroscopy and orbital interactions in carbonyl and cyanide bonding and the photophysical behavior of metal cyano complexes is also included.

Near-Synchronous And Delayed Initiation Of Long Run-Out Submarine Sediment Flows From A Record-Breaking River Flood, Offshore Taiwan, L. Carter, Jd Milliman, Pj Talling, R Gavey, Rb Wynn

VIMS Articles

Subsea fiber-optic telecommunication cables can break under fast sediment flows that travel 100s of kilometers through the deep ocean in response to earthquakes and submarine landslides. Similar flows are inferred to form from major river floods whose sediment-laden waters plunge and travel along the seabed. However, the complex initiation of flood-related flows and their hazard potential have not been observed until now. Here we use cable fault data from the Gaoping Canyon/Manila Trench off Taiwan to show that a major river flood, formed during Typhoon Morakot (2009), generated two, long run-out, destructive sediment flows; one during peak flood and the …

Synthesis And Properties Of Two Prodan-Based Fluorescent Models Of Cholesterol, Christopher J. Abelt

Arts & Sciences Articles

The syntheses and photophysical properties of 1-(5-methylhexyl)-2,3,7,8-tetrahydro-1H-naphtho[2,1-e]indo1-9(6H)-one (7a) and 1-(5-methylhexyl)-23,8,9-terrahydro-1H-naphrho[2,1-e]indol-6(7H)-one (7b) are reported. They are prepared in eight steps from the corresponding bromonaphthylamines. These fluorescent compounds have PRODAN-like cores, and they are structurally similar to cholesterol. Compound 7a is the first reported PRODAN derivative where both the amino and carbonyl groups are constrained to be coplanar with the naphthalene core. Comparing the photophysical behavior of these compounds with related compounds indicates that locking the amino group in a five-membered ring enhances their desirable properties as solvent polarity sensors. (C) 2012 Elsevier B.V. All rights reserved.

Virginia Shellfish Aquaculture Situation And Outlook Report : Results Of The 2011 Virginia Shellfish Aquaculture Crop Reporting Survey, Thomas J. Murray, Karen Hudson

Reports

The shellfish aquaculture industry in Virginia continues to grow, adding significant value to the state’s seafood marketplace. Today, watermen continue to harvest both hard clams and oysters from the state’s public resources, albeit at diminished rates. At the same time, Virginia’s watermen-farmers are providing growing quantities of additional quality shellfish to consumers. In recent years, folliowing the lead of the hard clam industry, a significant transition to intensive aquaculture of native oysters is underway. The once-extensive oyster planting utilizing wild seed has contracted primarily as a result of endemic oyster diseases and increasing wildlife predation of seed oysters. In its …

Combining Observational And Numerical Model Results To Improve Estimates Of Hypoxic Volume In Chesapeake Bay, A. J. Bever, Marjorie A.M. Friedrichs, Carl T. Friedrichs, M. E. Scully

Presentations

No abstract provided.

Insulator-To-Metal Transition And Correlated Metallic State Of V 2 O 3 Investigated By Optical Spectroscopy, M. K. Stewart, D. Brownstead, (...), M. M. Qazilbash, Et Al.

Arts & Sciences Articles

The optical properties of V2O3 thin films are investigated across the insulator-to-metal transition and in the metallic state. The spectral weight transfer observed across the transition, over an energy scale of 5 eV, is consistent with the Mott-Hubbard model for correlated electron systems. In the metallic phase, a strong Drude peak is observed, which exhibits a pronounced temperature dependence related to the transfer of states from the Hubbard bands to the quasiparticle peaks as the temperature is reduced. The analysis of the far-infrared spectra reveals signatures of strong electronic correlations in V2O3. Finally, a comparison to VO2 data is presented.

Coupled-Channel Theory Of Photoionization Microscopy, L. B. Zhao, I. I. Fabrikant, John B. Delos, F. Lepine, S. Cohen, C. Bordas

Arts & Sciences Articles

We develop a quantum-mechanical coupled-channel theory to simulate spatial distributions of electron current densities, produced in photoionization for nonhydrogenic atoms in the presence of a uniform external electric field. The coupled Schrodinger equations are numerically solved using the renormalized Numerov method. The expression for the outgoing wave function for photoelectrons ejected from the nonhydrogenic atomic source is derived. The theory is applied to investigations of photoionization for ground-state Li atoms. The distributions of electron current densities are computed and compared to the corresponding experimental images. Excellent agreement is obtained. It is, furthermore, found that the presence of the nonhydrogenic residual …

Virginia Game Fish Tagging Program Annual Report 2011, Susanna Musick, Lewis Gillingham

Reports

Through 2011, the Virginia Game Fish Tagging Program has maintained a 17-year database of records for tagged and recaptured fish. The program is a co-operative project of the Virginia Saltwater Fishing Tournament (under the Virginia Marine Resources Commission-VMRC) and the Virginia Institute of Marine Science (VIMS) of the College of William and Mary (under the VIMS Marine Advisory Program).

Monitoring Relative Abundance Of American Shad In Virginia Rivers 2011 Annual Report, Eric J. Hilton, Rob Latour, Brian Watkins, Ashleigh Magee

Reports

Concern about the decline in landings of American shad (Alosa sapidissima) along the Atlantic coast prompted the development of an interstate fisheries management plan (FMP) under the auspices of the Atlantic States Marine Fisheries Management Program (ASMFC 1999). Legislation enables imposition of federal sanctions on fishing in those states that fail to comply with the FMP. To be in compliance, coastal states are required to implement and maintain fishery-dependent and fishery-independent monitoring programs as specified by the FMP. For Virginia, these requirements include spawning stock assessments, the collection of biological data on the spawning run (e.g., age-structure, sex ratio, and …

Spatial And Temporal Trends In Tidal Flat Shape In San Francisco Bay, J. A. Bearman, Carl T. Friedrichs, B. E. Jaffe, A. C. Foxgrover

Presentations

No abstract provided.

Ecological And Erosion Protection Functions Of Chesapeake Bay Living Shorelines : Comprehensive Monitoring Of Ecological And Erosion Protection Functions Of Chesapeake Bay Living Shorelines (Cmls), Phase Ii, Donna Marie Bilkovic, Molly Mitchell

Reports

Armoring shorelines to prevent erosion, improve access, and accommodate individual landscaping interests can result in fragmentation or loss of habitats, reduction in capacity to moderate pollutant loads delivered to coastal waters, reduction in nekton and macrobenthic integrity (Bilkovic et al. 2005, King et al. 2005, Seitz et al. 2006, Bilkovic et al. 2006, Bilkovic & Roggero 2008), increases in invasive species, such as Phragmites australis (Chambers et al. 1999, King et al. 2007), and disturbance of sediment budgets sustaining adjacent properties. As an alternative to traditional armoring of shorelines, shoreline protection techniques incorporating natural elements from the system are increasingly …

Living Shorelines Policy: The Integration Of Shoreline Management And Planning, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

Rivers & Coast is a periodic publication of the Center for Coastal Resources Management, Virginia Institute of Marine Science. The goal of Rivers & Coast is to keep readers well informed of current scientific understanding behind key environmental issues related to watershed rivers and coastal ecosystems of the Chesapeake Bay.

Catlett Islands: Shoreline Change And Habitat Assessment Report, C. Scott Hardaway Jr., Donna A. Milligan, Christine A. Wilcox, Mary C. Cox

Reports

The Catlett Islands are located approximately 35.2 kilometers (21.9 miles) from the mouth of the York River in Gloucester County, Virginia (Figure 1) and represent mesohaline conditions (8-18 parts per thousand (ppt)). The Islands lie within the lower estuarine reaches of the York River and are offshore of Timberneck Farm between Timberneck and Cedarbush Creeks on the north shore of the York River. They are separated from the Farm by tidal wetlands and creeks. The islands consist of parallel ridges of forested wetlands surrounded by extensive saltmarshes. The purpose of this project is to assess shoreline rates of change, estimate …

Electronic Correlations And Unconventional Spectral Weight Transfer In The High-Temperature Pnictide Bafe2-Xcoxas2 Superconductor Using Infrared Spectroscopy, A. A. Schafgans, S. J. Moon, (...), M. M. Qazilbash, Et Al.

Arts & Sciences Articles

We report an infrared optical study of the pnictide high-temperature superconductor BaFe1.84Co0.16As2 and its parent compound BaFe2As2. We demonstrate that electronic correlations are moderately strong and do not change across the spin-density wave transition or with doping. By examining the energy scale and direction of spectral weight transfer, we argue that Hund's coupling J is the primary mechanism that gives rise to correlations.

Collaborative Research: The Role Of Wind In Estuarine Dynamics, Upper Chesapeake Bay, Vims Instruments Deployed In Collaboration With Umces And Whoi; March-May, 2012 Deployment., Grace M. Cartwright, Kelsey A. Fall, Carl T. Friedrichs, William C. Boicourt, Malcolm E. Scully

Data

While the project is a collaborative effort involving several researchers from the Virginia Institute of Marine Science (VIMS), the University of Maryland Center for Environmental Science (UMCES) and the Woods Hole Oceanographic Institution (WHOI), the Data archive here is primarily from VIMS owned instrumentation deployed as part of the project. A series of instruments were deployed in three transects in Upper Chesapeake Bay, South of the Choptank River from March to May 2012. This Dataset was collected with autonomously deployed Acoustic Doppler Current Profilers (ADCP), Acoustic Doppler Velicometers (ADV), and Conductivity and Temperature Sensors (CT).

Virginia Wetlands Report Vol. 27, No. 1, Virginia Institute Of Marine Science, Center For Coastal Resources Management

Virginia Wetlands Reports

Sea Level Rise - State of the Science

Breath-By-Breath Analysis Of Cardiorespiratory Interaction For Quantifying Developmental Maturity In Premature Infants, Matthew T. Clark, Craig G. Rusin, John L. Hudson, Hoshik Lee, John B. Delos, Et Al.

Arts & Sciences Articles

Breath-by-breath analysis of cardiorespiratory interaction for quantifying developmental maturity in premature infants. J Appl Physiol 112: 859-867, 2012. First published December 15, 2011; doi:10.1152/japplphysiol.01152.2011.-In healthy neonates, connections between the heart and lungs through brain stem chemosensory pathways and the autonomic nervous system result in cardiorespiratory synchronization. This interdependence between cardiac and respiratory dynamics can be difficult to measure because of intermittent signal quality in intensive care settings and variability of heart and breathing rates. We employed a phase-based measure suggested by Sch fer and coworkers (Sch fer C, Rosenblum MG, Kurths J, Abel HH. Nature 392: 239-240, 1998) to obtain …

Shoreline Evolution: Lancaster County, Virginia Rappahannock River And Chesapeake Bay Shorelines 2012, Donna A. Milligan, Christine A. Wilcox, C. Scott Hardaway Jr., Mary C. Cox

Reports

ancaster County is situated along the Rappahannock River and Chesapeake Bay (Figure 1). The County has 330 miles of tidal shoreline (Lancaster, 2007). Through time, the County’s shoreline has evolved, and determining the rates and patterns of shore change provides the basis to know how a particular coast has changed through time and how it might proceed in the future. Along Chesapeake Bay’s estuarine shores, winds, waves, tides and currents shape and modify coastlines by eroding, transporting and depositing sediments. The purpose of this report is to document how the shore zone of Lancaster County has evolved since 1937. Aerial …

Estimating Relative Abundance Of Young-Of-Year American Eel, Anguilla Rostrata, In The Virginia Tributaries Of Chesapeake Bay (Spring 2011), Troy D. Tuckey, Mary C. Fabrizio

Reports

The Atlantic States Marine Fisheries Commission (ASMFC) adopted the Interstate Fishery Management Plan (FMP) for the American eel in November 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 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 YOY eels over time [to produce a] qualitative appraisal of the annual recruitment of American eel to the U.S. Atlantic Coast” (ASMFC 2000). The development of these surveys began in 2000 with full implementation …

Shoreline Evolution: Middlesex County, Virginia Rappahannock River And Piankatank River Shorelines, Donna A. Milligan, Christine Wilcox, C. Scott Hardaway Jr., Mary C. Cox

Reports

Middlesex County is situated along the Rappahannock and Piankatank Rivers (Figure 1). Through time, the County’s shoreline has evolved, and determining the rates and patterns of shore change provides the basis to know how a particular coast has changed through time and how it might proceed in the future. Along Chesapeake Bay’s estuarine shores, winds, waves, tides and currents shape and modify coastlines by eroding, transporting and depositing sediments. The purpose of this report is to document how the shore zone of Middlesex County has evolved since 1937. Aerial imagery was taken for most of the Bay region beginning that …

Results Of The Us Ioos Testbed For Comparison Of Hydrodynamic And Dissolved Oxygen Models Of The Chesapeake Bay, M.A.M. Friedrichs, A. J. Bever, M. E. Scully, W. Long

Presentations

Results from multiple 3-D hydrodynamic and dissolved oxygen models for Chesapeake Bay have been compared to each other and to EPA monitoring data for the years 2004 and 2005. On seasonal time-scales, the models all do well in capturing fundamental aspects of the hydrodynamic and oxygen fields, although the intensity of the pycnocline is underestimated. Models with constant net respiration independent of nutrient supply reproduce hypoxia nearly as well as much more complex, nutrient-dependent ecological models. Seasonal variation in DO was insensitive to seasonal cycles in the respiration rate, freshwater input, and density stratification. Rather, seasonal variation in DO was …

Use Of Acoustic Doppler Velocimeters (Advs) To Infer Relationships Among Fine Sediment Settling, Bed Erodibility And Particle Type, York River Estuary, Va, K. A. Fall, Carl T. Friedrichs, Grace M. Cartwright

Presentations

Bed erodibility and particle settling velocity are key factors influencing fine sediment dynamics in coastal and estuarine environments. In order to better constrain inherently complex, temporally-varying relationships among hydrodynamics, bed properties and particle types, near-bed ADVs have been maintained in the York River Estuary since 2006. The ADVs provide measurements of bottom stress, suspended sediment concentration (C, via calibrated backscatter), and particle settling velocity (Ws, via a Rouse balance). By assuming Ws to be the combined result of rapidly settling fecal pellets plus more slowly settling flocs, the time-varying fraction of pellets versus flocs can be estimated. Vertical integration of …

Dual Use Of A Sediment Mixing Tank For Calibrating Acoustic Backscatter And Direct Doppler Measurement Of Settling Velocity, Grace M. Cartwright, Carl T. Friedrichs, P. D. Panetta

Presentations

While the Acoustic Doppler Velocimeter (ADV) is designed to determine fluid velocity, it is important to recognize that it is actually the velocity of the scatterers themselves that is measured. Thus in a calibration tank designed to relate sediment-induced backscatter to sediment concentration, the vertical velocity registered by an ADV at a given point is actually the true fluid velocity plus the sediment’s settling velocity. And absent net vertical volume flux, the average vertical velocity registered by an ADV across a horizontal plane is equal to the mean sediment settling velocity. For this study, a series of ADV calibrations were …

Spring-Neap Variation In Fecal Pellet Properties Within Surficial Sediment Of The York River Stuary, Virginia, E. A. Wei, L. M. Kraatz, Carl T. Friedrichs

Presentations

Fecal pellet abundance was measured within the upper seabed of the York River Estuary as part of a larger study investigating relationships between fine sediment aggregates and bed erodibility. Sedimentalogical surveys were conducted twice a month during the spring and summer of 2011 to coincide with spring or neap tidal cycles. Particle size distributions were determined by sieving the sediment using three methods: 1) typical grain size analysis, 2) gentle agitation with seawater, 3) gentle agitation with deionized water. Each method used four sieves (150, 90, 63 and 45 microns) to constrain the size abundance of the particles. The study …

Relationships Between Erodibility And Fine-Grained Seabed Properties On Tidal To Seasonal Time-Scales, York River Estuary, Virginia, L. M. Kraatz, Carl T. Friedrichs, Grace M. Cartwright, K. A. Fall

Presentations

The complex bio-geo-physical nature of muddy particles in coastal and estuarine environments has limited our understanding of finegrained sediment dynamics. An ongoing sedimentalogical study within the York River Estuary is investigating controls on cohesive bed erodibility by assessing changes in seabed properties over varying timescales. During the spring and summer of 2010 and 2011, multiple GOMEX box cores were collected and subsampled for grain size, fecal pellet content, Gust chamber erodibility, and water content. Initial findings suggest that erodibility of the seabed increased during periods following seasonal deposition events. Higher erodibility was also generally found to coincide with peak spring …

Shoreline Evolution: King George County, Virginia Potomac River And Rappahannock River Shorelines, Donna A. Milligan, Christine Wilcox, C. Scott Hardaway Jr., Mary C. Cox

Reports

King George County is situated along the Potomac and the Rappahannock Rivers (Figure 1). Through time, the County’s shoreline has evolved, and determining the rates and patterns of shore change provides the basis to know how a particular coast has changed through time and how it might proceed in the future. Along Chesapeake Bay’s estuarine shores, winds, waves, tides, and currents shape and modify coastlines by eroding, transporting and depositing sediments.

The purpose of this report is to document how the shore zone of King George County has evolved since 1937. Aerial imagery was taken for most of the Bay …