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Full-Text Articles in Physical Sciences and Mathematics

Quantifying The Effects Of Land Use Change On Stream Ecosystems For Use In Ecological Risk Assessment, Katherine Sciera Dec 2008

Quantifying The Effects Of Land Use Change On Stream Ecosystems For Use In Ecological Risk Assessment, Katherine Sciera

All Dissertations

Land disturbance often results in a cascade of physical and chemical stressors to aquatic ecosystems which can impact their biotic integrity. This study examined three developing watersheds near Greenville, SC to evaluate the quantitative relationships between the physical stressors associated with land use alterations and biotic integrity. More specifically, the objectives of this study were to 1) quantify the mechanisms of aquatic ecosystem degradation in streams impacted by watershed urbanization, 2) demonstrate the use of quantitative relationships among the physical, chemical, and biological stressors associated with land use change in an established ecological risk assessment framework, and 3) identify the …


Synthesis, Structure And Magnetic Properties Of Oxy-Anion Based Magnetic Solids Containing Transition Metal Oxide Nanostructures, Kulugammana Gedera Ranmohotti Dec 2008

Synthesis, Structure And Magnetic Properties Of Oxy-Anion Based Magnetic Solids Containing Transition Metal Oxide Nanostructures, Kulugammana Gedera Ranmohotti

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Inline with the focus of our research, my goal for this dissertation study is to further explore new classes of magnetic insulators exhibiting novel properties. The scope of this work is twofold: 1) the exploratory synthesis of polyanion-based mixed-framework compounds containing transition metal oxide magnetic nanostructures, and 2) the investigation of the structure/property correlation with respect to the spin couplings in confined lattices. These studies are of fundamental and technological importance regarding the long-term development of low-dimensional magnetic solids for device applications in especially information storage and quantum computing. Several interesting and significant transition metal based silicate, phosphate arsenate and …


The Thermoelectric Properties Investigation Of X0.05Mo3Sb7-YTeY (X=Mn, Fe, Ni, Co; Y=1.5, 1.6, 1.7), Tim Holgate Dec 2008

The Thermoelectric Properties Investigation Of X0.05Mo3Sb7-YTeY (X=Mn, Fe, Ni, Co; Y=1.5, 1.6, 1.7), Tim Holgate

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With ever increasing energy costs, dwindling resources, and terms with the prefix 'green' filling headlines, the need for environmentally friendly energy sources has never been greater. Since the mid-20th century researchers have been pursuing greater efficiency in thermoelectric materials. Thermoelectric materials achieve energy conversion via the Seebeck effect (heat to electric power) and the Peltier effect (electricity to cooling power). Presented herein are the measured electrical and thermal transport properties and phenomenal analysis of the Ir3Ge7-type system: X0.05Mo3Sb7-yTey (X=Mn, Fe, Ni, Co; y=1.5, 1.6, 1.7) where 'X' are interstitially …


Magnetohydrodynamic Effects In Propagating Relativistic Jets: Reverse Shock And Magnetic Acceleration, Yosuke Mizuno, Bing Zhang, Bruno Giacomazzo, Ken-Ichi Nishikawa, Phillip E. Hardee, Shigehiro Nagataki, Dieter H. Hartmann Dec 2008

Magnetohydrodynamic Effects In Propagating Relativistic Jets: Reverse Shock And Magnetic Acceleration, Yosuke Mizuno, Bing Zhang, Bruno Giacomazzo, Ken-Ichi Nishikawa, Phillip E. Hardee, Shigehiro Nagataki, Dieter H. Hartmann

Publications

We solve the Riemann problem for the deceleration of an arbitrarily magne-tized relativistic flow injected into a static unmagnetized medium in one dimen-sion. We find that for the same initial Lorentz factor, the reverse shock becomes progressively weaker with increasing magnetization σ (the Poynting-to-kinetic energy flux ratio), and the shock becomes a rarefaction wave when σ exceeds a critical value, σc, defined by the balance between the magnetic pressure in the flow and the thermal pressure in the forward shock. In the rarefaction wave regime, we find that the rarefied region is accelerated to a Lorentz factor that is significantly …


A Performance And Productivity Study Using Mpi, Titanium, And Fortress, Amy Apon, Chris Bryan, Wesley Emeneker Dec 2008

A Performance And Productivity Study Using Mpi, Titanium, And Fortress, Amy Apon, Chris Bryan, Wesley Emeneker

Publications

The popularity of cluster computing has increased focus on usability, especially in the area of programmability. Languages and libraries that require explicit message passing have been the standard. New languages, designed for cluster computing, are coming to the forefront as a way to simplify parallel programming. Titanium and Fortress are examples of this new class of programming paradigms. This papers presents results from a productivity study of these two newcomers with MPI, the de- facto standard for parallel programming.


Synthesis, Characterization, And Application Of Ag Nanostructures, Stephen Hudson Dec 2008

Synthesis, Characterization, And Application Of Ag Nanostructures, Stephen Hudson

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Noble metal nanoparticles (NPs) have been used for many centuries; however their properties were not truly scrutinized until Michael Farady's investigations in the 1850's. Advances in the field of nanotechnology over the last three decades have enabled insights into the properties of materials as their dimensions are reduced to the nanoscale. The repercussions of these insights are seen in many modern applications.
In this dissertation, properties of novel nanostructures based on Ag NPs are presented and discussed. The exceptional optical properties of Ag NPs stem from the collective oscillations of the conduction electrons known as plasmon resonances. The excitation of …


Fabrication And Optical Properties Of Noble Metal Nanostructures, Mark Kinnan Dec 2008

Fabrication And Optical Properties Of Noble Metal Nanostructures, Mark Kinnan

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Experimental and theoretical results are presented in Chapters 2, 3, and 4 on the effects of dielectric medium, particle size, and interparticle distance, respectively, on plasmon coupling in two-dimensional arrays of silver nanoparticles. The arrays were fabricated via the self-assembly of single crystal particles from c.a. 46 nm to 287 nm on PVP-modified glass substrates. Spin-coated poly(methylmethacrylate) layers were used to immobilize the particles and prevent their surface aggregation. Varying the thickness of the PMMA layer made it possible to change the average dielectric medium between the particles. UV-Visible spectra of different arrays were compared to the corresponding electron microscope …


Fluorescent Conjugated Polymer Dots For Single Molecule Imaging And Sensing Applications, Changfeng Wu Dec 2008

Fluorescent Conjugated Polymer Dots For Single Molecule Imaging And Sensing Applications, Changfeng Wu

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While single molecule imaging and sensing hold the promise of providing unprecedented detail about cellular processes, many advanced applications are limited by the lack of appropriate fluorescence probes. In many cases, currently available fluorescent labels are not sufficiently bright and photostable to overcome the background associated with various autofluorescence and scattering processes. This dissertation describes research efforts focused on the development of a novel class of fluorescent nanoparticles called conjugated polymers dots (CPdots) for single molecule fluorescence detection. The CPdots contain highly fluorescent π-conjugated polymers that have been refined over the last decades as the active material in polymer light-emitting …


Two Categories Of Refutation Decision Procedures For Classical And Intuitionistic Propositional Logic, Edward Doyle Dec 2008

Two Categories Of Refutation Decision Procedures For Classical And Intuitionistic Propositional Logic, Edward Doyle

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An automatic theorem prover is a computer program that proves theorems without the assistance of a human being. Theorem proving is an important basic tool in proving theorems in mathematics, establishing the correctness of computer programs, proving the correctness of communication protocols, and verifying integrated circuit designs.
This dissertation introduces two new categories of theorem provers, one for classical propositional logic and another for intuitionistic propositional logic. For each logic a container property and generalized algorithm are introduced.
Many methods have been developed over the years to prove theorems in propositional logic. This dissertation describes and presents example proofs for …


Characterization Of Campus Parking Lot Stormwater And Remediation Of Risks Using Constructed Wetland Treatment Systems, Andrew Mcqueen Dec 2008

Characterization Of Campus Parking Lot Stormwater And Remediation Of Risks Using Constructed Wetland Treatment Systems, Andrew Mcqueen

All Theses

Campus parking lot stormwater (CPLSW) runoff mobilizes a variety of constituents from vehicular and atmospheric deposition that may pose risks to receiving aquatic systems. The overall objective of this research was to provide an approach for risk characterization, toxicity identification, and remediation of constituents of concern in CPLSW. The specific objectives of this research were to: (1) Characterize campus parking lot stormwater (CPLSW) to discern the constituents of concern present in these waters; (2) Perform TIE manipulations to identify possible fractions of concern in CPLSW, and; (3) Evaluate the performance of a pilot-scale constructed wetland treatment system (CWTS) designed to …


Insights Into Biogeophysical Signatures Using Polarization Force Microscopy, Elizabeth Bartosik Dec 2008

Insights Into Biogeophysical Signatures Using Polarization Force Microscopy, Elizabeth Bartosik

All Theses

The success of bioremediation strategies is dependent upon effective monitoring of microorganisms in the subsurface. Induced polarization (IP) may represent a cost-effective, complementary technique to existing borehole-based microbe detection schemes. Recent studies show a significant, yet poorly understood IP effect associated with the presence of bacteria in aqueous and porous media. This effect is believed to be rooted in the physicochemical surface interactions between cells and minerals which we probe using polarization force microscopy. Polarization force experiments were conducted on a hydrated mica surface using the gram positive bacterium Bacillus subtilis and the gram negative bacterium Escherichia coli. On all …


Transformation Of Sulfonamide Antibiotics On Soil Mineral Oxides, Baishu Guo Dec 2008

Transformation Of Sulfonamide Antibiotics On Soil Mineral Oxides, Baishu Guo

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Determining the occurrence and potential adverse effects of antibiotic pharmaceuticals released into the environment is a critical step towards responsible environmental stewardship. Under aqueous conditions typically found in soils and natural waters, the antibiotic agent sulfamethoxazole (SMX) was transformed in the presence of pyrolusite MnO2 via oxidative pathways. At least 50% loss of SMX was observed after 269 hr in acidic and basic solutions (pH 3-9). A maximum of 100% loss was recorded at pH 3 and 66% loss was recorded at circumneutral pH. Concomitantly, aqueous manganese concentrations increased to around 10 µM at pH 3 and 2 µM at …


Application Of Web Services To A Simulation Framework, Matthew Bennink Dec 2008

Application Of Web Services To A Simulation Framework, Matthew Bennink

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The Joint Semi-Automated Forces (JSAF) simulator is an excellent tool for military training and a great testbed for new SAF behaviors. However, it has the drawback that behaviors must be ported into its own Finite State Machine (FSM) language. Web Services is a growing technology that seamlessly connects service providers to service consumers. This work attempts to merge these two technologies by modeling SAF behaviors as web services. The JSAF simulator is then modeled as a web service consumer.
This approach allows new Semi-Automated Forces (SAF) behaviors to be developed independently of the simulator, which provides the developer with greater …


Probing Grb Environments Through X-Ray Absorption, Hala Eid Dec 2008

Probing Grb Environments Through X-Ray Absorption, Hala Eid

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Although long-duration GRBs (LGRBs) are highly transient in nature, their early afterglow can in principle be detected to very high redshifts (Lamb & Reichart, 2000). This makes them potent probes of the chemical evolution and content of the high-redshift universe. In this work, we use photoelectric absorption observed in the XRT spectra of LGRBs to investigate the evolution of metallicities and hydrogen column densities of LGRB host galaxies. Using a high-quality sample of LGRBs indicates the presence of a weak anti-correlation between the abundances and redshift. We also find an evolution trend in intrinsic column density. To confirm these correlations, …


The Origin Of The 511 Kev Positron Annihilation Emission Morphology, Bethany Johns Dec 2008

The Origin Of The 511 Kev Positron Annihilation Emission Morphology, Bethany Johns

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The 511 keV positron annhilation emission from the Galactic bulge has yet to solely be attributed to any astrophysical source of positrons. The 511 keV line, characteristic of electron-positron annihilation, was discovered in 1970 by Johnson and Haymes [1973] almost 40 years ago. Most recently the INTERnational Gamma-Ray Astrophysical Laboratory (INTEGRAL) [Knodlseder 1997] has measured the annihilation rates of both components of the Galaxy. The bulge and disk annihilation rates are (1.5 ± 0.1) x 10^43 e+ s^-1 and(0.3 ± 0.2) x 10^43 e+ s^-1, respectively. The ratio of the bulge rate to that of the disk ranges from 3-9. …


Calculations Of Diffusion In Fcc Binary Alloys Using On-The-Fly Kinetic Monte Carlo, Erdi Bleda Dec 2008

Calculations Of Diffusion In Fcc Binary Alloys Using On-The-Fly Kinetic Monte Carlo, Erdi Bleda

All Dissertations

With the recent advancements in computer technologies and the improvements in simulation algorithms, along with the theories, has allowed scientists to carry out diffusion calculations more efficiently, especially for the cases where either the diffusion itself takes longer, or there is no available isotope to carry out the diffusion experiments such as tracer diffusion.
In this work, we present a systematic approach to diffusion in intermetallic alloys such as weakly clustered Cu — Ni and weakly ordered Au — Ag. We use Accelerated Molecular Dynamics (AMD) combined with the Embedded Atom Method (EAM) to find the necessary saddlepoint energies. With …


Novel Lactide Derived Polymers; Synthesis, Properties And Applications, Dahlia Haynes Dec 2008

Novel Lactide Derived Polymers; Synthesis, Properties And Applications, Dahlia Haynes

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This dissertation primarily encompasses the synthesis, characterization, properties and discussion of applications for lactide derived polymers. The methodology focuses on altering polylactide's (PLA's) dynamic and physical properties increasing its broad market utility in both traditional and non-traditional applications. The fundamentals of this work include understanding and enhancing the polymer chemistry and materials related processes through the use of copolymerization, fluorination, composite chemistry and materials science.
The first chapter discusses the important of this research with emphasis on current world issues that focuses on the feasibility of renewable resources and sustainability implementation. Modification of renewable resource materials like lactic acid is …


Hybrid Bond-Order Potential For Silicon, Suleiman Oloriegbe Dec 2008

Hybrid Bond-Order Potential For Silicon, Suleiman Oloriegbe

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ABSTRACT
A new hybrid bond-order potential for silicon is developed. The functional form of the potential is derived from hybrid of expressions from empirical bond-order formalism and first principles approximations. The total energy is expressed as the sum of attractive, repulsive and promotion energies. By introducing a screening function derived from approximations to first principles expressions, the potential is made long-ranged by allowing covalent interactions beyond the first nearest neighbor shell of atoms in agreement with quantum mechanical descriptions of the bonding in silicon. Environment-dependent promotion energy is introduced that accurately accounts for energetic interactions due to changes in hybridization …


Synthesis And Characterization Of Biodegradable Polyurethanes For Biomedical Application, Changhong Zhang Dec 2008

Synthesis And Characterization Of Biodegradable Polyurethanes For Biomedical Application, Changhong Zhang

All Dissertations

This dissertation constitutes the studies about the biomedical materials research of novel polyurethanes. These elastic and degradable polyurethanes exhibited the potential for drug delivery, scaffold fabrication by novel ink-jet printing technology or other biomedical applications. This dissertation includes two parts about two different types of polyurethanes.
In the first part of this dissertation, we studied a polyurethane that was synthesized from methylene di-p-phenyl-diisocyanate (MDI), polycaprolactone diol (PCL-diol) and N, N-bis (2-hydorxyethyl)-2-aminoethane-sulfonic acid (BES). MDI, PCL-diol and BES were polymerized into polyurethane and served as the hard segment, soft segment and chain extender respectively. The effects of the chain extender BES …


Solarization Effects On Chemical Properties Of Soils Under Kudu (Pueraria Montana) Invasion, Nicole Gilbert Dec 2008

Solarization Effects On Chemical Properties Of Soils Under Kudu (Pueraria Montana) Invasion, Nicole Gilbert

All Theses

Solarization is an effective method for managing small areas with kudzu (Pueraria montana) invasions that may alter soil chemical properties. Conducted from 2005 to 2007 at the Clemson University Experimental Forest in Clemson, South Carolina on a Cecil clay loam (fine, kaolinitic, thermic Typic Kanhapludult), this study compares soil chemical properties under thermally-treated and non-treated plots at different depths invaded by Kudzu.
The experimental factors of treatment and depth were arranged in a factorial treatment design with 15 treatments arranged in a split plot design. The five thermal treatments were the whole plot factors which were arranged in a randomized …


Physics Of Type Ia Supernovae, Ginger Bryngelson Dec 2008

Physics Of Type Ia Supernovae, Ginger Bryngelson

All Theses

Type Ia supernovae (SNe Ia), the thermonuclear explosion of a white dwarf, were once considered standard candles. However, increased observations reveal inhomogeneities in chemical composition and luminosity behavior, roughly dividing SNe Ia into three luminosity classes; super-luminous, sub-luminous, and normally-luminous. After introducing the problem in the context of previous observations and modeling, this thesis explores the physical processes occurring in a SN Ia after explosion, and discusses observations of SN light curves.
A simple model of the expanding ejecta calculates the energy deposition from the decay of radioactive Ni56 as well as photon diffusion. It produces light curves that match …


Multiwavelength Analysis Of The Intriguing Grb 061126: The Reverse Shock Scenario And Magnetization, A. Gomboc, S. Kobayashi, C. Guidorzi, A. Melandri, V. Mangano, B. Sbarufatti, C. G. Mundell, P. Schady, R. J. Smith, A C. Updike, D A. Kann, K Misra, E Rol, A Pozanenko, A J. Castro-Tirado, G C. Anupama, D Bersier, M F. Bode, D Carter, P Curran, A Fruchter, J Graham, Dieter H. Hartmann, M Ibrahimov, A Levan, A Monfardini, C J. Mottram, P T. O'Brien, P Prema, D K. Sahu, I A. Steele, N R. Tanvir, K Wiersema Nov 2008

Multiwavelength Analysis Of The Intriguing Grb 061126: The Reverse Shock Scenario And Magnetization, A. Gomboc, S. Kobayashi, C. Guidorzi, A. Melandri, V. Mangano, B. Sbarufatti, C. G. Mundell, P. Schady, R. J. Smith, A C. Updike, D A. Kann, K Misra, E Rol, A Pozanenko, A J. Castro-Tirado, G C. Anupama, D Bersier, M F. Bode, D Carter, P Curran, A Fruchter, J Graham, Dieter H. Hartmann, M Ibrahimov, A Levan, A Monfardini, C J. Mottram, P T. O'Brien, P Prema, D K. Sahu, I A. Steele, N R. Tanvir, K Wiersema

Publications

We present a detailed study of the prompt and afterglow emission from Swift GRB 061126 using BAT, XRT, UVOT data and multicolor optical imaging from 10 ground-based telescopes. GRB 061126 was a long burst (T90 ¼191 s) with four overlapping peaks in its -ray light curve. The X-ray afterglow, observed from 26 minutes to 20 days after the burst, shows a simple power-law decay with X ¼1:290 Æ0:008. Optical observations presented here cover the time range from 258 s (Faulkes Telescope North) to 15 days (Gemini North) after the burst; the decay rate of the optical afterglow shows a steep-to-shallow …


Multicolor Conjugated Polymer Dots For Biological Fluorescence Imaging, Changfeng Wu, Barbara Bull, Craig Szymanski, Kenneth Christensen, Jason Mcneill Nov 2008

Multicolor Conjugated Polymer Dots For Biological Fluorescence Imaging, Changfeng Wu, Barbara Bull, Craig Szymanski, Kenneth Christensen, Jason Mcneill

Publications

Highly fluorescent conjugated polymer dots were developed for demanding applications such as fluorescence imaging in live cells. These nanoparticles exhibit small particle diameters, extraordinary fluorescence brightness, and excellent photostability. Single particle fluorescence imaging and kinetic studies indicate much higher emission rates (∼108 s−1) and little or no blinking of the nanoparticles as compared to typical results for single dye molecules and quantum dots. Analysis of single particle photobleaching trajectories reveals excellent photostability—as many as 109 or more photons emitted per nanoparticle prior to irreversible photobleaching. The superior figures of merit of these new fluorescent probes, together …


Modelling Growth And Predicting Future Developed Land In The Upstate Of South Carolina, Craig E. Campbell, Jeffery Allen, Kang Shou Lu Oct 2008

Modelling Growth And Predicting Future Developed Land In The Upstate Of South Carolina, Craig E. Campbell, Jeffery Allen, Kang Shou Lu

S.C. Water Resources Conference

2008 S.C. Water Resources Conference Addressing Water Challenges Facing the State and Region


An Assessment Of Water Quality And Urbanization In The Gills Creek Watershed, Jessica Artz Oct 2008

An Assessment Of Water Quality And Urbanization In The Gills Creek Watershed, Jessica Artz

S.C. Water Resources Conference

2008 S.C. Water Resources Conference Addressing Water Challenges Facing the State and Region


Hydrologic And Water Quality Monitoring On Turkey Creek Watershed, Francis Marion National Forest, Sc, D M. Amatya, T J. Callahan, A Radecki-Pawlik, P Drewes, C Trettin, W F. Hansen Oct 2008

Hydrologic And Water Quality Monitoring On Turkey Creek Watershed, Francis Marion National Forest, Sc, D M. Amatya, T J. Callahan, A Radecki-Pawlik, P Drewes, C Trettin, W F. Hansen

S.C. Water Resources Conference

2008 S.C. Water Resources Conference - Addressing Water Challenges Facing the State and Region


Cooperative Restoration Programs In Critical Habitats In The Upper South Carolina Coastal Region, J M. Whetstone, C L. Page, C A. Gresham, M C. Nespeca Oct 2008

Cooperative Restoration Programs In Critical Habitats In The Upper South Carolina Coastal Region, J M. Whetstone, C L. Page, C A. Gresham, M C. Nespeca

S.C. Water Resources Conference

2008 S.C. Water Resources Conference - Addressing Water Challenges Facing the State and Region


Human Health & Water Issues - Micro & Macro: Harmful Algal Blooms, Climate Change & Infectious Diseases Disaster-Related H20 Injuries, Illnesses, Robert Ball Oct 2008

Human Health & Water Issues - Micro & Macro: Harmful Algal Blooms, Climate Change & Infectious Diseases Disaster-Related H20 Injuries, Illnesses, Robert Ball

S.C. Water Resources Conference

2008 S.C. Water Resources Conference - Addressing Water Challenges Facing the State and Region


Alcoa-Mt. Holly Zero Process Water Discharge Using Phytotechnology, Lauren Schmelter Oct 2008

Alcoa-Mt. Holly Zero Process Water Discharge Using Phytotechnology, Lauren Schmelter

S.C. Water Resources Conference

2008 S.C. Water Resources Conference - Addressing Water Challenges Facing the State and Region


Recovery, Reuse, And Recycling Of Debris From The Demolition Of The Grace And Pearman Bridges At Charleston, South Carolina, Fred L. Cooper Oct 2008

Recovery, Reuse, And Recycling Of Debris From The Demolition Of The Grace And Pearman Bridges At Charleston, South Carolina, Fred L. Cooper

S.C. Water Resources Conference

2008 S.C. Water Resources Conference - Addressing Water Challenges Facing the State and Region