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2010

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Articles 6211 - 6240 of 6945

Full-Text Articles in Physical Sciences and Mathematics

A Systematic Study Of The Dispersion Of Swnts In Organic Solvents, Qiaohuan Cheng, Sourabhi Debnath, Luke O'Neill, Theresa Hedderman, Elizabeth Gregan Jan 2010

A Systematic Study Of The Dispersion Of Swnts In Organic Solvents, Qiaohuan Cheng, Sourabhi Debnath, Luke O'Neill, Theresa Hedderman, Elizabeth Gregan

Articles

Dispersions of as-produced HiPco single-walled carbon nanotubes (SWNTs) in a series of organic solvents were prepared by dilution with the aid of tip sonication. Mild centrifugation (945 g) was carried out to remove large bundles. Atomic force microscopy (AFM) studies revealed that the bundle size decreased as the dispersion was diluted. By measuring the UV−vis−NIR absorption before and after centrifugation as a function of the concentration, the dispersion limit of SWNTs in each solvent can be determined. Correlations between the dispersion limit and solvent solubility parameters, including the Hildebrand solubility parameter and three-dimensional Hansen solubility parameters, are explored, demonstrating that …


Sonolytic Degradation Of Parathion And The Formation Of Byproducts, Juan Juan Yao, Nai Yun Gao, Yang Deng, Yan Ma, Hai Jun Li, Bin Xu, Lei Li Jan 2010

Sonolytic Degradation Of Parathion And The Formation Of Byproducts, Juan Juan Yao, Nai Yun Gao, Yang Deng, Yan Ma, Hai Jun Li, Bin Xu, Lei Li

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Ultrasonic degradation of parathion has been investigated in this study. At a neutral condition, 99.7% of 2.9 μM parathion could be decomposed within 30 min under 600 kHz ultrasonic irradiation at ultrasonic intensity of 0.69 W/cm2. The degradation rate increased proportionally with the increasing ultrasonic intensity from 0.10 to 0.69 W/cm2. The parathion degradation was enhanced in the presence of dissolved oxygen due to formation of more {radical dot}OH, but was inhibited in the presence of nitrogen gas owning to the free radical scavenging effect in vapor phase within the cavitational bubbles. CO32 -, HCO3-, and Cl- exhibited the inhibiting …


E-Carrel: An Environment For Collaborative Textual Scholarship, George K. Thiruvathukal, Steven E. Jones, Peter Shillingsburg Jan 2010

E-Carrel: An Environment For Collaborative Textual Scholarship, George K. Thiruvathukal, Steven E. Jones, Peter Shillingsburg

Computer Science: Faculty Publications and Other Works

The E-Carrel project aims to address the preservation of, access to, and re-uses of humanities electronic text files. It enables dynamic, growing resource projects as repositories for new knowledge. It provides for on-line distributed data and tools that are open to new scholarly enhancement through a user friendly tagging tool, sophisticated use of stand-off markup and annotation (leveraging RDF capabilities), and a browsing system anyone can use. It creates a secure system of text preparation and dissemination that encourages collaboration and participation by anyone interested in the texts. To insure the endurance of authenticated texts, multiple copies are distributed on …


Computer-Guided Solutions To Physics Problems Using Prolog, Thomas J. Bensky, Catherine A. Taff Jan 2010

Computer-Guided Solutions To Physics Problems Using Prolog, Thomas J. Bensky, Catherine A. Taff

Physics

By posing a continual stream of pertinent questions, a nonmathematical computer program can prod freshman physics students toward an analytical solution to one-dimensional kinematics problems.


Review Of Sustainable Energy – Without The Hot Air By David Mackay, David W. Hafemeister Jan 2010

Review Of Sustainable Energy – Without The Hot Air By David Mackay, David W. Hafemeister

Physics

No abstract provided.


Defining A Standard Metric For Electricity Savings, Jonathan Koomey, Hashem Akbari, Carl Blumstein, Marilyn Brown, Richard Brown, Chris Calwell, Sheryl Carter, Ralph Cavanagh, Audrey Chang, David Claridge, Paul Craig, Rick Diamond, Joseph H. Eto, William Fulkerson, Ashok Gadgil, Howard Geller, José Goldemberg, Chuck Goldman, David B. Goldstein, Steve Greenberg, David W. Hafemeister, Jeff Harris, Hal Harvey, Eric Heitz, Eric Hirst, Holmes Hummel, Dan Kammen, Henry Kelly, Skip Laitner, Mark Levine, Amory Lovins, Gil Masters, James E. Mcmahon, Alan Meier, Michael Messenger, John Millhone, Evan Mills, Steve Nadel, Bruce Nordman, Lynn Price, Joe Romm, Marc Ross, Michael Rufo, Jayant Sathaye, Lee Schipper, Stephen H. Schneider, James L. Sweeney, Malcolm Verdict, Diana Vorsatz, Devra Wang, Carl Weinberg, Richard Wilk, John Wilson, Ernst Worrell Jan 2010

Defining A Standard Metric For Electricity Savings, Jonathan Koomey, Hashem Akbari, Carl Blumstein, Marilyn Brown, Richard Brown, Chris Calwell, Sheryl Carter, Ralph Cavanagh, Audrey Chang, David Claridge, Paul Craig, Rick Diamond, Joseph H. Eto, William Fulkerson, Ashok Gadgil, Howard Geller, José Goldemberg, Chuck Goldman, David B. Goldstein, Steve Greenberg, David W. Hafemeister, Jeff Harris, Hal Harvey, Eric Heitz, Eric Hirst, Holmes Hummel, Dan Kammen, Henry Kelly, Skip Laitner, Mark Levine, Amory Lovins, Gil Masters, James E. Mcmahon, Alan Meier, Michael Messenger, John Millhone, Evan Mills, Steve Nadel, Bruce Nordman, Lynn Price, Joe Romm, Marc Ross, Michael Rufo, Jayant Sathaye, Lee Schipper, Stephen H. Schneider, James L. Sweeney, Malcolm Verdict, Diana Vorsatz, Devra Wang, Carl Weinberg, Richard Wilk, John Wilson, Ernst Worrell

Physics

The growing investment by governments and electric utilities in energy efficiency programs highlights the need for simple tools to help assess and explain the size of the potential resource. One technique that is commonly used in this effort is to characterize electricity savings in terms of avoided power plants, because it is easier for people to visualize a power plant than it is to understand an abstraction such as billions of kilowatt-hours. Unfortunately, there is no standardization around the characteristics of such power plants.
In this letter we define parameters for a standard avoided power plant that have physical meaning …


Psc 307: Nuclear Weapons Arms Control, David Hafemeister Jan 2010

Psc 307: Nuclear Weapons Arms Control, David Hafemeister

Physics

No abstract provided.


Computational Fluctuating Fluid Dynamics, Alejandro Garcia, J. B. Bell, S. Williams Jan 2010

Computational Fluctuating Fluid Dynamics, Alejandro Garcia, J. B. Bell, S. Williams

Faculty Publications

This paper describes the extension of a recently developed numerical solver for the Landau-Lifshitz Navier-Stokes (LLNS) equations to binary mixtures in three dimensions. The LLNS equations incorporate thermal fluctuations into macroscopic hydrodynamics by using white-noise fluxes. These stochastic PDEs are more complicated in three dimensions due to the tensorial form of the correlations for the stochastic fluxes and in mixtures due to couplings of energy and concentration fluxes (e.g., Soret effect). We present various numerical tests of systems in and out of equilibrium, including time-dependent systems, and demonstrate good agreement with theoretical results and molecular simulation


Table Of Contents Jan 2010

Table Of Contents

Journal of Digital Forensics, Security and Law

No abstract provided.


Avoiding Sanctions At The E-Discovery Meet-And-Confer In Common Law Countries, Milton Luoma, Vicki Luoma Jan 2010

Avoiding Sanctions At The E-Discovery Meet-And-Confer In Common Law Countries, Milton Luoma, Vicki Luoma

Journal of Digital Forensics, Security and Law

The rules of civil procedure in common law countries have been amended to better deal with the requirements of electronic discovery. One of the key changes in case management is the scheduling of a meet-and-confer session where the parties to litigation must meet early in the case before any discovery procedures have begun to exchange information regarding the nature, location, formats, and pertinent facts regarding custody and control of a party’s electronically stored information (ESI). Failure to abide by the rules and participate in good faith at the meet-and-confer session can have dire consequences for the parties and lawyers involved. …


Malware Forensics: Discovery Of The Intent Of Deception, Murray Brand, Craig Valli, Andrew Woodward Jan 2010

Malware Forensics: Discovery Of The Intent Of Deception, Murray Brand, Craig Valli, Andrew Woodward

Journal of Digital Forensics, Security and Law

Malicious software (malware) has a wide variety of analysis avoidance techniques that it can employ to hinder forensic analysis. Although legitimate software can incorporate the same analysis avoidance techniques to provide a measure of protection against reverse engineering and to protect intellectual property, malware invariably makes much greater use of such techniques to make detailed analysis labour intensive and very time consuming. Analysis avoidance techniques are so heavily used by malware that the detection of the use of analysis avoidance techniques could be a very good indicator of the presence of malicious intent. However, there is a tendency for analysis …


Marine Benthic Habitat Mapping Of Muir Inlet, Glacier Bay National Park And Preserve, Alaska With An Evaluation Of The Coastal And Marine Ecological Classification Standard Iii, Luke D. Mitchell, Guy R. Cochrane, Lisa Etherington, Ross D. Powell, Larry A. Mayer Jan 2010

Marine Benthic Habitat Mapping Of Muir Inlet, Glacier Bay National Park And Preserve, Alaska With An Evaluation Of The Coastal And Marine Ecological Classification Standard Iii, Luke D. Mitchell, Guy R. Cochrane, Lisa Etherington, Ross D. Powell, Larry A. Mayer

Center for Coastal and Ocean Mapping

Seafloor geology and potential benthic habitats were mapped in Muir Inlet, Glacier Bay National Park and Preserve, Alaska, using multibeam sonar, ground-truth information, and geological interpretations. Muir Inlet is a recently deglaciated fjord that is under the influence of glacial and paraglacial marine processes. High glacially derived sediment and meltwater fluxes, slope instabilities, and variable bathymetry result in a highly dynamic estuarine environment and benthic ecosystem. We characterize the fjord seafloor and potential benthic habitats using the Coastal and Marine Ecological Classification Standard (CMECS) recently developed by the National Oceanic and Atmospheric Administration (NOAA) and NatureServe. Substrates within Muir Inlet …


Endocrine Disruptors And Obesity: An Examination Of Selected Persistent Organic Pollutants In The Nhanes 1999-2002 Data, Mai A. Elobeid, Miguel A. Padilla, David W. Brock, Douglas M. Ruden, David B. Allison Jan 2010

Endocrine Disruptors And Obesity: An Examination Of Selected Persistent Organic Pollutants In The Nhanes 1999-2002 Data, Mai A. Elobeid, Miguel A. Padilla, David W. Brock, Douglas M. Ruden, David B. Allison

Psychology Faculty Publications

Recent evidence suggests that endocrine disrupting chemicals (EDCs) may cause perturbations in endogenous hormonal regulation that predispose to weight gain. Using data from NHANES (1999-2002), we investigated the association between body mass index (BMI), waist circumference (WC) and selected persistent organic pollutants (POPs) via multiple linear regressions. Consistent interaction was found between gender, ln oxychlordane and ln p,p' DDT. Also, we found an association between WC and ln oxychlordane and ln hpcdd in subjects with detectable levels of POPs, whereas an association between WC and ln p,p' DDT was observed in all subjects. Furthermore, ln Ocdd showed an increase with …


An Examination Of The Association Of Selected Toxic Metals With Total And Central Obesity Indices: Nhanes 99-02, Miguel A. Padilla, Mai Elobeid, Douglas M. Ruden, David B. Allison Jan 2010

An Examination Of The Association Of Selected Toxic Metals With Total And Central Obesity Indices: Nhanes 99-02, Miguel A. Padilla, Mai Elobeid, Douglas M. Ruden, David B. Allison

Psychology Faculty Publications

It is conceivable that toxic metals contribute to obesity by influencing various aspects of metabolism, such as by substituting for essential micronutrients and vital metals, or by inducing oxidative stress. Deficiency of the essential metal zinc decreases adiposity in humans and rodent models, whereas deficiencies of chromium, copper, iron, and magnesium increases adiposity. This study utilized the NHANES 99-02 data to explore the association between waist circumference and body mass index with the body burdens of selected toxic metals (barium, cadmium, cobalt, cesium, molybdenum, lead, antimony, thallium, and tungsten). Some of the associations were significant direct relationships (barium and thallium), …


The Effects Of A Freshwater Diversion Of Nekton Species Biomass Distributions, Food Web Pathways, And Community Structure In A Louisiana Estuary, Kim De Mutsert Jan 2010

The Effects Of A Freshwater Diversion Of Nekton Species Biomass Distributions, Food Web Pathways, And Community Structure In A Louisiana Estuary, Kim De Mutsert

LSU Doctoral Dissertations

A current method to restore Louisiana’s estuaries includes reintroducing freshwater and sediments to wetlands that are hydrologically isolated from the Mississippi River due to the construction of levees. In this dissertation, I examined effects of the second largest freshwater diversion in Louisiana, the Caernarvon Freshwater Diversion (CFD), on estuarine nekton in Breton Sound. Before focusing on Breton Sound, I examined the status of nekton communities in the northern Gulf of Mexico (GOM), and Louisiana wetlands in particular, using the mean trophic level index (MTLI). I demonstrated that commercial targeting caused the previously reported low and declining MTLI from the GOM. …


Studies Of Nanoparticles From A Group Of Uniform Materials Based On Organic Salts (Gumbos), Aaron Tesfai Jan 2010

Studies Of Nanoparticles From A Group Of Uniform Materials Based On Organic Salts (Gumbos), Aaron Tesfai

LSU Doctoral Dissertations

Tesfai, Aaron, B.S., B.A., University of Missouri, Columbia, 2003 Doctor of Philosophy, Spring Commencement 2010 Major: Chemistry Studies of Nanoparticles from a Group of Uniform Materials Based on Organic Salts (GUMBOS) Dissertation directed by Professor Isiah M. Warner Pages in dissertation, 101. Words in abstract, 271. Ionic liquids (ILs) are defined as organic salts composed of ions with melting points at or below 100 °C. ILs have gained considerable attention because of their desirable properties such as low volatility, high thermal stability, and tunability. GUMBOS are an emergent class of organic salts, many of which are ionic liquids (ILs). However, …


Choosing Between Remote I/O Versus Staging In Distributed Environments, Ibrahim Hakki Suslu Jan 2010

Choosing Between Remote I/O Versus Staging In Distributed Environments, Ibrahim Hakki Suslu

LSU Doctoral Dissertations

Today, scientifi_x000C_c applications and experiments have become increasingly complex and more demanding in terms of their computational and data requirements. The amount of data generated and used has grown at a very rapid rate. As tens or hundreds of terabytes of data for a single application is very common today; petabytes and even exabytes of data will be very common in a few years. One of the major challenges in distributed computing environments is how to access these large datasets remotely over the network. Data staging and remote I/O are the most widely used data access methods for distributed applications. …


Upland Nesting Waterfowl Population Responses To Predator Reduction In North Dakota, Matthew R. Pieron Jan 2010

Upland Nesting Waterfowl Population Responses To Predator Reduction In North Dakota, Matthew R. Pieron

LSU Doctoral Dissertations

Population growth for mallards (Anas platyrhynchos), and presumably other upland nesting ducks, in the Prairie Pothole Region is most sensitive to nest success, and nest success is most strongly influenced by predation. I evaluated the efficacy of reducing predator populations to improve nest success and increase local breeding populations of upland nesting ducks on township-sized (93.2 km2) management units in eastern North Dakota, USA, during 2005−2008. I also examined potential territorial limitations on local population growth for mallards. Trappers annually removed an average of 245 predators per trapped site. I monitored 7,489 nests on 7 trapped and 5 nontrapped sites, …


Algorithms For Upper Bounds Of Low Dimensional Group Homology, Joshua D. Roberts Jan 2010

Algorithms For Upper Bounds Of Low Dimensional Group Homology, Joshua D. Roberts

University of Kentucky Doctoral Dissertations

A motivational problem for group homology is a conjecture of Quillen that states, as reformulated by Anton, that the second homology of the general linear group over R = Z[1/p; ζp], for p an odd prime, is isomorphic to the second homology of the group of units of R, where the homology calculations are over the field of order p. By considering the group extension spectral sequence applied to the short exact sequence 1 → SL2 → GL2 → GL1 → 1 we show that the calculation of the homology …


Upper Bounds On The Splitting Of The Eigenvalues, Phuoc L. Ho Jan 2010

Upper Bounds On The Splitting Of The Eigenvalues, Phuoc L. Ho

University of Kentucky Doctoral Dissertations

We establish the upper bounds for the difference between the first two eigenvalues of the relative and absolute eigenvalue problems. Relative and absolute boundary conditions are generalization of Dirichlet and Neumann boundary conditions on functions to differential forms respectively. The domains are taken to be a family of symmetric regions in Rn consisting of two cavities joined by a straight thin tube. Our operators are Hodge Laplacian operators acting on k-forms given by the formula Δ(k) = dδ+δd, where d and δ are the exterior derivatives and the codifferentials respectively. A result …


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

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 …


Thermal Degradation Studies On Pmma–Het Acid Based Oligoesters Blends, Thangamani Rajkumar, Chinnaswamy Thangavel Vijayakumar, Palanichamy Sivasamy, Bojja Sreedhar, Charles A. Wilkie Jan 2010

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.


Structure-Activity Relationships Of Pai-1 Inhibitors, Karen Sanders Jan 2010

Structure-Activity Relationships Of Pai-1 Inhibitors, Karen Sanders

Master's Theses and Doctoral Dissertations

The inhibition of plasminogen activator inhibitor-1 (PAI-1) is anticipated to increase our understanding of various human ailments with which high levels of PAI-1 have been associated, including diabetes, stroke, and atherosclerosis. Previous accounts have reported the synthesis of inhibitors that bind to PAI-1 with a low affinity, inhibit the serpin plasma protein antithrombin III, and/or fail to inhibit PAI-1 when vitronectin, a cofactor of PAI-1 is present. The synthesis of small-molecule inhibitors of PAI-1 that improve upon these properties has been the main goal of this research. Research efforts focused on examining changes in inhibitor potency based on the manipulation …


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

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 Jan 2010

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 …


Subgroups Of The Torelli Group, Leah R. Childers Jan 2010

Subgroups Of The Torelli Group, Leah R. Childers

LSU Doctoral Dissertations

Let Mod(Sg) be the mapping class group of an orientable surface of genus g, Sg. The action of Mod(Sg) on the homology of Sg induces the well-known symplectic representation:

Mod(Sg) ---> Sp(2g, Z).
The kernel of this representation is called the Torelli group, I(Sg).

We will study two subgroups of I(Sg). First we will look at the subgroup generated by all SIP-maps, SIP(Sg). We will show SIP(Sg) is not I(Sg) and is in fact an infinite index subgroup of I(Sg). We will also classify which SIP-maps are in the kernel of the Johnson homomorphism and Birman-Craggs-Johnson homomorphism.

Then we will …


Cross-Talk-Free Dual-Color Fluorescence Cross-Correlation Spectroscopy For High-Throughtput Screening, Wonbae Lee Jan 2010

Cross-Talk-Free Dual-Color Fluorescence Cross-Correlation Spectroscopy For High-Throughtput Screening, Wonbae Lee

LSU Doctoral Dissertations

High throughput processing of chemical/biochemical information is critical in many areas, such as genome sequencing, drug discovery and clinical diagnostics. Integral to collecting information at high rates with the necessary throughput is the development of systems that can not only monitor the results with high precision and accuracy, but also prepare and process samples prior to the analytical measurement. To achieve the required throughput, we have conducted work directed toward developing a system that provides detection sensitivity at the single-molecule detection (SMD) level. The research was first focused on the development of a sensitive strategy for the detection of proteins …


Analysis And Modeling Of Hurricane Impacts On A Coastal Louisiana Lake Bottom, Angelina Freeman Jan 2010

Analysis And Modeling Of Hurricane Impacts On A Coastal Louisiana Lake Bottom, Angelina Freeman

LSU Doctoral Dissertations

Tropical cyclone impacts on wetland, terrestrial, and shelf systems have been previously studied and reasonably delineated, but little is known about the response of coastal lakes to storm events. For the first time, tropical cyclone impacts on a shallow coastal lake in the Louisiana coastal plain have been studied using direct lines of evidence and numerical modeling. Using side-scan sonar, CHIRP subbottom and echo sounder bathymetric profiles, the lake bottom and shallow subsurface of Sister Lake was imaged pre- and post-Hurricanes Katrina and Rita to provide a geologic framework for assessing the effects of these storms. Box cores were collected …


Chemistry Of Rhenium(I) Tricarbonyl Complexes Of Biomedical Relevance, Theshini Perera Jan 2010

Chemistry Of Rhenium(I) Tricarbonyl Complexes Of Biomedical Relevance, Theshini Perera

LSU Doctoral Dissertations

fac-[ReI(CO)3L]n complexes serve as models for short-lived fac-[99mTcI(CO)3L] imaging tracers. Dangling groups on L, needed to achieve desirable biodistribution, complicate the NMR spectra, which are not readily understood. In fac-[ReI(CO)3L]+ with less complicated L, NH groups (exo-NH) projecting toward the L face sometimes showed an upfield shift attributable to steric shielding of the exo-NH group from the solvent by the chelate rings. To investigate whether exo-NH groups in six-membered rings exhibit the same effect and whether the …


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

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