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Modeling The Vertical Distributions Of Downwelling Plane Irradiance And Diffuse Attenuation Coefficient In Optically Deep Waters, X. J. Pan, Richard C. Zimmerman 2010 Old Dominion University

Modeling The Vertical Distributions Of Downwelling Plane Irradiance And Diffuse Attenuation Coefficient In Optically Deep Waters, X. J. Pan, Richard C. Zimmerman

OES Faculty Publications

The diffuse attenuation coefficient Kᵈ is critical to understand the vertical distribution of underwater downwelling irradiance (Eᵈ). Theoretically Eᵈ is composed of the direct solar beam and the diffuse sky irradiance. Applying the statistical results from Hydrolight radiative transfer simulations, Kᵈ is expressed into a mathematical equation (named as PZ06) integrated from the contribution of direct solar beam and diffuse sky irradiance with the knowledge of sky and water conditions. The percent root mean square errors (RMSE) for the vertical distribution of Eᵈ(z) under various sky and water conditions between PZ06 and Hydrolight results are typically less than 4%. Field …


The Widespread Occurrence Of Coupled Carbonate Dissolution/Reprecipitation In Surface Sediments On The Bahamas Bank, David J. Burdige, Xinping Hu, Richard C. Zimmerman 2010 Old Dominion University

The Widespread Occurrence Of Coupled Carbonate Dissolution/Reprecipitation In Surface Sediments On The Bahamas Bank, David J. Burdige, Xinping Hu, Richard C. Zimmerman

OES Faculty Publications

Using two complimentary approaches (pore water advection/diffusion/reaction modeling and stable isotope mass balance calculations) we show that carbonate dissolution/reprecipitation occurs on early diagenetic time scales across a broad range of sediments on the Great Bahamas Bank. The input of oxygen into the sediments, which strongly controls sediment carbonate dissolution, has two major sources belowground input by seagrasses (that is, seagrass O2 pumping), and permeability-driven advective pore water exchange. The relative importance of these O2 delivery mechanisms depends on both seagrass density, and on how bottom water flow interacts with the seagrass canopy and leads to this advective exchange. …


The Path To Preservation: Using Proteomics To Decipher The Fate Of Diatom Proteins During Microbial Degradation, Brook L. Nunn, Ying S. Ting, Lars Malmström, Yihsuan S. Tsai, Angela Aquier, David R. Goodlett, H. Rodger Harvey 2010 Old Dominion University

The Path To Preservation: Using Proteomics To Decipher The Fate Of Diatom Proteins During Microbial Degradation, Brook L. Nunn, Ying S. Ting, Lars Malmström, Yihsuan S. Tsai, Angela Aquier, David R. Goodlett, H. Rodger Harvey

OES Faculty Publications

We drew upon recent advances in tandem mass spectrometry-based proteomic analyses in order to examine the proteins that remain after a diatom bloom enters the stationary phase, precipitates out of the photic zone, and is subjected to microbial degradation over a 23-d period within a controlled laboratory environment. Proteins were identified from tandem mass spectra searched against three different protein databases in order to track proteins from Thalassiosira pseudonana and any potential bacterial contributions. A rapid loss of diatom protein was observed over the incubation period; 75% of the proteins initially identified were not detected after 72 h of exposure …


A Shortened Synthesis Of Optically Pure Tricarbonyl[Methyl (2e,4e)-6-Oxo-2,4-Hexadienoate]Iron Leading To Improved Yield, Rajesh K. Pandey, Sergey Lindeman, William Donaldson 2010 Marquette University

A Shortened Synthesis Of Optically Pure Tricarbonyl[Methyl (2e,4e)-6-Oxo-2,4-Hexadienoate]Iron Leading To Improved Yield, Rajesh K. Pandey, Sergey Lindeman, William Donaldson

Chemistry Faculty Research and Publications

The (+)- and (–)-enantiomers of tricarbonyl[methyl (2E,4E)-6-oxo-2,4-hexadienoate]iron are prepared in 4 steps from commercially available hexadienal (26% and 25% yields, respectively).


Resin-Modified Glass-Ionomer Setting Reaction Competition, David W. Berzins, S. Abey, M. C. Costache, Charles A. Wilkie, H. W. Roberts 2010 Marquette University

Resin-Modified Glass-Ionomer Setting Reaction Competition, David W. Berzins, S. Abey, M. C. Costache, Charles A. Wilkie, H. W. Roberts

Chemistry Faculty Research and Publications

Resin-modified glass ionomers (RMGI) set by at least 2 mechanisms dependent upon reactant diffusion prior to gelation. Each reaction’s kinetics and setting mechanism may rely on and/or compete with the other. In this study, we investigated RMGI setting reaction interactions using differential scanning calorimetry (DSC) by varying light-cure initiation times. A RMGI was analyzed with isothermal and dynamic temperature scan DSC with light-curing occurring immediately, or at 5 or 10 minutes after mixing as well as without light-activation. Results show that as time allowed for the acid-base reaction increased, the light-activation polymerization exotherm decreased. Conversely, analysis of DSC data suggests …


Anion Exchange Kinetics Of Nanodimensional Layered Metal Hydroxides: Use Of Isoconversional Analysis, Stephen Majoni, Jeanne Hossenlopp 2010 Marquette University

Anion Exchange Kinetics Of Nanodimensional Layered Metal Hydroxides: Use Of Isoconversional Analysis, Stephen Majoni, Jeanne Hossenlopp

Chemistry Faculty Research and Publications

Anion exchange reactions of nanodimensional layered metal hydroxide compounds are utilized to create materials with targeted physical and chemical properties and also as a means for controlled release of intercalated anions. The kinetics of this important class of reaction are generally characterized by model-based approaches. In this work, a different approach based on isothermal, isoconversional analysis was utilized to determine effective activation energies with respect to extent of reaction. Two different layered metal hydroxide materials were chosen for reaction with chloride anions, using a temperature range of 30−60 °C. The concentrations of anions released into solution and the changes in …


Infrared Spectroelectrochemical Reduction Of Iron Porphyrin Complexes, Zhongcheng Wei, Michael D. Ryan 2010 Marquette University

Infrared Spectroelectrochemical Reduction Of Iron Porphyrin Complexes, Zhongcheng Wei, Michael D. Ryan

Chemistry Faculty Research and Publications

The spectroelectrochemistry of iron porphinones and their nitrosyl complexes were examined by infrared spectroscopy, as well as ferrous octaethylporphyrin nitrosyl. With the use of d8-THF, the solvent was transparent down to 1200 cm−1. For the porphinones, the reduction of the macrocycle ring could be observed by the changes in the νCO band and, for the nitrosyl complex, the changes in the nitrosyl ligand were directly observable from the νNO band. Formation of the ferrous complexes led to a small downshift in the νCO band. Further reduction to the formal Fe(“I”) complex led to …


Thermal Degradation Studies On Pmma–Het Acid Based Oligoesters Blends, Thangamani Rajkumar, Chinnaswamy Thangavel Vijayakumar, Palanichamy Sivasamy, Bojja Sreedhar, Charles A. Wilkie 2010 Kamaraj College of Engineering and Technology

Thermal Degradation Studies On Pmma–Het Acid Based Oligoesters Blends, Thangamani Rajkumar, Chinnaswamy Thangavel Vijayakumar, Palanichamy Sivasamy, Bojja Sreedhar, Charles A. Wilkie

Chemistry Faculty Research and Publications

Imparting thermal stability to polymethyl methacrylate (PMMA) without affecting its optical clarity is attempted by incorporating HET acid based oligoesters. Pure PMMA and PMMA containing five and 20 wt% of four different oligoesters are separately prepared using bulk polymerization. The thermal properties of the materials studied using DSC, TG, TG–FTIR and Pyr–GC–MS are presented. The main volatile degradation products identified are CO, HCl, CO2, H2O, hexachlorocyclopentadiene, hexachloroendomethylene tetrahydrophthalic acid/anhydride and methyl methacrylate. A detailed mechanism for the influence of the degradation products of HET acid based oligoesters on the thermal degradation of PMMA is also presented.


Immobilization Of The Aminopeptidase From Aeromonas Proteolytica On Mg2+/Al3+ Layered Double Hydroxide Particles, Steven T. Frey, Stephanie L. Guilmet, Richard G. Egan III, Alyssa Bennett, Sarah R. Soltau, Richard C. Holz 2010 Skidmore College

Immobilization Of The Aminopeptidase From Aeromonas Proteolytica On Mg2+/Al3+ Layered Double Hydroxide Particles, Steven T. Frey, Stephanie L. Guilmet, Richard G. Egan Iii, Alyssa Bennett, Sarah R. Soltau, Richard C. Holz

Chemistry Faculty Research and Publications

A novel biomaterial formed by the immobilization of the Aminopeptidase from Aeromonas proteolytica (AAP) on synthetic Mg2+ and Al3+ ion-containing layered double hydroxide (LDH) particles was prepared. Immobilization of AAP on the LDH particles in a buffered, aqueous mixture is rapid such that the maximum loading capacity, 1 × 10−9 moles of AAP/mg LDH, is achieved in a few minutes. X-ray powder diffraction of LDH samples before and after treatment with AAP indicates that the enzyme does not intercalate between the layers of LDH, but instead binds to the surface. Treatment of AAP/LDH with various amounts of …


Isomerization As A Key Path To Molecular Products In The Gas-Phase Decomposition Of Halons, Aimable Kalume, Lisa George, Scott Reid 2010 Marquette University

Isomerization As A Key Path To Molecular Products In The Gas-Phase Decomposition Of Halons, Aimable Kalume, Lisa George, Scott Reid

Chemistry Faculty Research and Publications

The decomposition of halons remains controversial concerning the branching between radical and molecular products. The latter channel, where it has been found, is presumed to occur via a constrained symmetric multicenter transition state. Isomerization pathways in the gas-phase chemistry of halons have rarely been considered, despite the fact that the iso-halons, which feature a halogen−halogen bond, are widely recognized as important reactive intermediates in condensed phases. In this Letter, detailed calculations and modeling of the unimolecular decomposition of several important halons, including CF2Cl2, CF2Br2, and CHBr3, reveal that isomerization is …


Tricarbonylrhenium(I) And Manganese(I) Complexes Of 2-(Pyrazolyl)-4-Toluidine, Brendan J Liddle, Sarath Wanniarachchi, Sergey V. Lindeman, James R. Gardinier 2010 Marquette University

Tricarbonylrhenium(I) And Manganese(I) Complexes Of 2-(Pyrazolyl)-4-Toluidine, Brendan J Liddle, Sarath Wanniarachchi, Sergey V. Lindeman, James R. Gardinier

Chemistry Faculty Research and Publications

A series of tricarbonyl rhenium(I) and manganese(I) complexes of the electroactive 2-(pyrazolyl)-4-toluidine ligand, H(pzAnMe), has been prepared and characterized including by single crystal X-ray diffraction studies. The reactions between H(pzAnMe) and M(CO)5Br afford fac-MBr(CO)3[H(pzAnMe)] (M = Mn, 1a; Re, 1b) complexes. The ionic species {fac-M(CH3CN)(CO)3[H(pzAnMe)]}(PF6) (M = Mn, 2a; Re, 2b) were prepared by metathesis of 1a or 1b with TlPF6 in acetonitrile. Complexes 1a and 1b partly ionize to {M(CH3CN)(CO)3[H(pzAnMe)]+ …


Breaking The Cycle: Impact Of Sterically-Tailored Tetra(Pyrazolyl)Lutidines On The Self-Assembly Of Silver(I) Complexes, Tyler James Morin, Andrew Merkel, Sergey V. Lindeman, James R. Gardinier 2010 Marquette University

Breaking The Cycle: Impact Of Sterically-Tailored Tetra(Pyrazolyl)Lutidines On The Self-Assembly Of Silver(I) Complexes, Tyler James Morin, Andrew Merkel, Sergey V. Lindeman, James R. Gardinier

Chemistry Faculty Research and Publications

A improved preparation of the pentadentate ligand α,α,α′,α′-tetra(pyrazolyl)lutidine, pz4lut, and the syntheses of three new alkyl-substituted pyrazolyl derivatives pz4′4lut (pz4′ = 4-methylpyrazolyl), pz*4lut (pz* = 3,5-dimethylpyrazolyl), and pzDIP4lut (pzDIP = 3,5-diisopropylpyrazolyl) are described. The silver(I) complexes of these ligands were studied to ascertain the impact of pyrazolyl substitution, if any, on their binding modes and on solubility issues. In the solid state, [Ag(pz4lut)](BF4) (1), [Ag(pz4′4lut)](BF4) (2), and [Ag(pz*4lut)](BF4) (3 …


Benthic Ecology From Space: Optics And Net Primary Production In Seagrass And Benthic Algae Across The Great Bahama Bank, Heidi M. Dierssen, Richard C. Zimmerman, Lisa A. Drake, David J. Burdige 2010 Old Dominion University

Benthic Ecology From Space: Optics And Net Primary Production In Seagrass And Benthic Algae Across The Great Bahama Bank, Heidi M. Dierssen, Richard C. Zimmerman, Lisa A. Drake, David J. Burdige

OES Faculty Publications

Development of repeatable and quantitative tools are necessary for determining the abundance and distribution of different types of benthic habitats, detecting changes to these ecosystems, and determining their role in the global carbon cycle. Here we used ocean color remote sensing techniques to map different major groups of primary producers and estimate net primary productivity (NPP) across Great Bahama Bank (GBB). Field investigations on the northern portion of the GBB in 2004 revealed 3 dominant types of benthic primary producers: seagrass, benthic macroalgae, and microalgae attached to sediment. Laboratory measurements of NPP ranged from barely net autotrophic for grapestone sediment …


Affinity Capillary Electrophoretic Study Of K+/Na+ Selectivity Of Hexaarylbenzene-Based Polyaromatic Receptor, Sille Ehala, Rajendra Rathore, Emanuel Makrlik, Petr Toman, Václav Kašička 2010 Academy of Sciences of the Czech Republic

Affinity Capillary Electrophoretic Study Of K+/Na+ Selectivity Of Hexaarylbenzene-Based Polyaromatic Receptor, Sille Ehala, Rajendra Rathore, Emanuel Makrlik, Petr Toman, Václav Kašička

Chemistry Faculty Research and Publications

Affinity capillary electrophoretic (ACE) study has proved the selectivity of hexaarylbenzene-based polyaromatic receptor (R) for K+ ion over Na+ ion. The apparent binding constants of the R complexes with K+ and Na+ ions were determined from the dependence of effective electrophoretic mobility of R on the concentration of the above alkali metal ions in the background electrolyte using a non-linear regression analysis. The apparent binding constants (Kb) of the K-R+ and Na–R+ complexes in methanolic medium were evaluated as log Kb = 3.20 ± 0.22 for the K–R+ complex, and log Kb≅−0.7 for the Na–R+ complex.


Effect Of The Heterotrophic Dinoflagellate Oxyrrhis Marina And The Copepod Acartia Tonsa On Vertical Carbon Flux In And Around Thin Layers Of The Phytoflagellate Isochrysis Galbana, A. B. Bochdansky, S. M. Bollens, G. C. Rollwagen-Bollens, A. H. Gibson 2010 Old Dominion University

Effect Of The Heterotrophic Dinoflagellate Oxyrrhis Marina And The Copepod Acartia Tonsa On Vertical Carbon Flux In And Around Thin Layers Of The Phytoflagellate Isochrysis Galbana, A. B. Bochdansky, S. M. Bollens, G. C. Rollwagen-Bollens, A. H. Gibson

OES Faculty Publications

Dynamics of material and energy flow through food webs differ when resources are allocated in patches in comparison to situations in which the same resources are distributed evenly throughout the water column. Thin layers of plankton are special cases of such resource patches. While previous studies have predominantly focused on the response of organisms to these layers, we investigated how 2 types of grazers in turn affect thin layers. In an experimental study with tightly controlled environmental conditions, we monitored the redistribution of particulate organic (POC), dissolved organic (DOC) and inorganic (DIC) carbon from thin layers of Isochrysis galbana. …


Role Of Macroscopic Particles In Deep-Sea Oxygen Consumption, Alexander B. Bochdansky, Hendrik M. Van Aken, Gerhard J. Herndl 2010 Old Dominion University

Role Of Macroscopic Particles In Deep-Sea Oxygen Consumption, Alexander B. Bochdansky, Hendrik M. Van Aken, Gerhard J. Herndl

OES Faculty Publications

Macroscopic particles (> 500 µg), including marine snow, large migrating zooplankton, and their fast-sinking fecal pellets, represent primary vehicles of organic carbon flux from the surface to the deep sea. In contrast, freely suspended microscopic particles such as bacteria and protists do not sink, and they contribute the largest portion of metabolism in the upper ocean. In bathy- and abyssopelagic layers of the ocean (2,000-6,000 m), however, microscopic particles may not dominate oxygen consumption. In a section across the tropical Atlantic, we show that macroscopic particle peaks occurred frequently in the deep sea, whereas microscopic particles were barely detectable. In …


Turbulent Mixing In A Strongly Forced Salt Wedge Estuary, David K. Ralston, W. Rockwell Geyer, James A. Lerczak, Malcolm Scully 2010 Old Dominion University

Turbulent Mixing In A Strongly Forced Salt Wedge Estuary, David K. Ralston, W. Rockwell Geyer, James A. Lerczak, Malcolm Scully

OES Faculty Publications

Turbulent mixing of salt is examined in a shallow salt wedge estuary with strong fluvial and tidal forcing. A numerical model of the Merrimack River estuary is used to quantify turbulent stress, shear production, and buoyancy flux. Little mixing occurs during flood tides despite strong velocities because bottom boundary layer turbulence is dislocated from stratification elevated in the water column. During ebbs, bottom salinity fronts form at a series of bathymetric transitions. At the fronts, near-bottom velocity and shear stress are low, but shear, stress, and buoyancy flux are elevated at the pycnocline. Internal shear layers provide the dominant source …


Sascha Vitzhum, Jim Browne (Interviewer) 2010 WGLT

Sascha Vitzhum, Jim Browne (Interviewer)

Interviews for WGLT

Jim Browne interviews Assistant Professor Sascha Vitzhum about virtual worlds, economics and marketing. (requires RealPlayer)


Landscape Values As A Determinant In Geotourism Development: A Case Study Of Utah, Usa, E. Papińska, Elzbieta Białkowska-Jelińska 2010 University of South Florida

Landscape Values As A Determinant In Geotourism Development: A Case Study Of Utah, Usa, E. Papińska, Elzbieta Białkowska-Jelińska

School of Geosciences Student Publications

The state of Utah is located in west-central United States. The area of 219 887 km2is populated by 2.8 million people (in 2009). Population density is relatively low: 12 persons per square km. The main reasons for low population density are unfavourable natural conditions. The most important are topography and climate. Utah’s landscape diversity is a consequence of a variety of terrain types. For that reason, there are 5 national parks (Zion, Bryce, Capitol Reef, Arches and Canyonlands), national monuments, and other lower rank protected areas established in Utah. Each of these places, characterized by unique types of …


Remote Access Forensics For Vnc And Rdp On Windows Platform, Paresh Kerai 2010 Edith Cowan University

Remote Access Forensics For Vnc And Rdp On Windows Platform, Paresh Kerai

Theses : Honours

There has been a greater implementation of remote access technologies in recent years. Many organisations are adapting remote technologies such as Virtual Network Computing (VNC) and remote desktop (RDP) applications as customer support application. They use these applications to remotely configure computers and solve computer and network issues of the client on spot. Therefore, the system administrator or the desktop technician does not have to sit on the client computer physically to solve a computer issue. This increase in adaptation of remote applications is of interest to forensic investigators; this is because illegal activities can be performed over the connection. …


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