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LSU Doctoral Dissertations

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Articles 931 - 960 of 1402

Full-Text Articles in Physical Sciences and Mathematics

Formation And Stabilization Of Combustion-Generated Environmentally Persistent Free Radicals On Transition Metal Oxides Supported On Silica, Eric Warren Pimentel Vejerano Jan 2011

Formation And Stabilization Of Combustion-Generated Environmentally Persistent Free Radicals On Transition Metal Oxides Supported On Silica, Eric Warren Pimentel Vejerano

LSU Doctoral Dissertations

The formation of environmentally persistent free radicals in combustion system was investigated from chemisorptions of chlorine- and hydroxy-substituted benzenes on transition metal oxide surface under post-combustion conditions. This manuscript reports the formation of EPFRs on silica particles containing 5% Fe(III)2O3, Ni(II)O, and Zn(II)O. The EPFRs are formed by the chemisorption of substituted aromatic molecular adsorbates on the metal cation center followed by electron transfer from the adsorbate to the metal ion at temperatures from 150 to 400 oC. Depending on the nature of the adsorbate and the temperature, two organic EPFRs were formed: a phenoxyl-type radical, which has a lower …

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Redox-Active Liposome Delivery Agents With Highly Controllable Stimuli-Responsive Behavior, Nicole Hollabaugh Carrier Jan 2011

Redox-Active Liposome Delivery Agents With Highly Controllable Stimuli-Responsive Behavior, Nicole Hollabaugh Carrier

LSU Doctoral Dissertations

Over the last few decades, liposomes have generated a lot of interest as drug delivery vehicles to address the need for providing both increased therapeutic efficacy and decreased systemic exposure, simultaneously. The challenge of increasing drug accumulation at diseased sites, without compromising the integrity and stability of the liposomal carrier during circulation, has been met with two possible solutions: (1) active targeting and (2) active triggering. To achieve selective and site-specific delivery of drugs to tumors, active triggering methods have been developed wherein a responsive element is incorporated into the liposomal bilayer, which causes destabilization of the liposome upon exposure …

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Characterization Of Triggerable Quinones For The Development Of Enzyme-Responsive Liposomes, Maria Fabiana Mendoza Jan 2011

Characterization Of Triggerable Quinones For The Development Of Enzyme-Responsive Liposomes, Maria Fabiana Mendoza

LSU Doctoral Dissertations

For decades, there has been a lot of focus on the development of new carriers for drug delivery applications. From all of the carriers, stimuli-responsive liposomes have been studied extensively, but only a handful have been enzyme-responsive liposomes. Therefore, the field of endogenous proteins as activators of liposomes is a fertile field worthy of exploration. The research described in this dissertation involves how structural changes on the quinone moiety altered their electronic properties, as well as their behavior toward the human enzyme NAD(P)H:quinone oxidoreductase type-1 (hNQO1, over expressed in certain tumor tissues), thus yielding a series of triggerable quinones to …

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Guided Modes And Resonant Transmission In Periodic Structures, Hairui Tu Jan 2011

Guided Modes And Resonant Transmission In Periodic Structures, Hairui Tu

LSU Doctoral Dissertations

We analyze resonant scattering phenomena of scalar fields in periodic slab and pillar structures that are related to the interaction between guided modes of the structure and plane waves emanating from the exterior. The mechanism for the resonance is the nonrobust nature of the guided modes with respect to perturbations of the wavenumber, which reflects the fact that the frequency of the mode is embedded in the continuous spectrum of the pseudo-periodic Helmholtz equation. We extend previous complex perturbation analysis of transmission anomalies to structures whose coefficients are only required to be measurable and bounded from above and below, and …

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Symmetric Spaces, Se-Jong Kim Jan 2011

Symmetric Spaces, Se-Jong Kim

LSU Doctoral Dissertations

We first review the basic theory of a general class of symmetric spaces with canonical reflections, midpoints, and displacement groups. We introduce a notion of gyrogroups established by A. A. Ungar and define gyrovector spaces slightly different from Ungar's setting. We see the categorical equivalence of symmetric spaces and gyrovector spaces with respect to their corresponding operations. In a smooth manifold with spray we define weighted means using the exponential map and develop the Lie-Trotter formula with respect to midpoint operation. Via the idea that we associate a spray with a Loos symmetric space, we construct an analytic scalar multiplication …

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Microphytobenthos Of The Northern Gulf Of Mexico Hypoxic Area And Their Role In Oxygen Dynamics, Melissa Millman Baustian Jan 2011

Microphytobenthos Of The Northern Gulf Of Mexico Hypoxic Area And Their Role In Oxygen Dynamics, Melissa Millman Baustian

LSU Doctoral Dissertations

The presence or absence of microphytobenthos on the seafloor provides clues about whether benthic oxygen evolution contributes significantly to the oxygen budget of the hypoxic area in the northern Gulf of Mexico. Hypoxia (oxygen < 2 mg l-1) creates inadequate concentrations of dissolved oxygen to support most organisms, such as fish, shrimp and crabs, and occurs over large areas of the Louisiana continental shelf from spring through summer in most years. Oxygen production by benthic autotrophs may offset a decline in oxygen concentrations if there is a functioning community and sufficient light. I sampled three stations (14, 20 and 23 m depths) ~ 100 km west of the Mississippi River over three hypoxic annual cycles (2006 – 2008), and 11 stations along a 14 - 20 m contour on the shelf in late-July in 2006, 2007 and 2008. I used microscopy and high-performance liquid chromatography to estimate the biomass and composition of phytoplankton and microphytobenthos. The potential seasonal oxygen production was estimated in 2007 and 2008 by incubating coupled light/dark sediment cores and bottom water from two stations. The sediment community (cells > 3 um) differed from those in the water column and were frequently benthic pennate diatoms and filamentous cyanobacteria (58-88% seasonally and 1-99% in mid-summer). The concentration of microphytobenthic biomass was usually < 2.0 ug g dry sed-1, and various biotic parameters were influenced by light at the seafloor. Declines in dissolved oxygen over a seasonal cycle in 2007 and 2008 were affected more by the initial dissolved oxygen concentration than by the presence of microphytobenthos that could generate oxygen. The sediment (1.2 - 27.3 mmol O2 m-2 d-1, n = 97) and bottom-water (1.1 - 17.5 mmol m-2 d-1, n = 23) oxygen consumption rates were within the range of the few previously-reported data. This work adds to these data and also provides the only sediment oxygen consumption rates at fixed sites over seasonal time scales. These results provide critical input to three-dimensional, physical-biological models of oxygen dynamics for this hypoxic area.

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Preparation And Studies Of Ratiometric Fluorescent Chemosensors Based On The Attenuation Of Excitation Energy Transfer, Jiba Raj Acharya Jan 2011

Preparation And Studies Of Ratiometric Fluorescent Chemosensors Based On The Attenuation Of Excitation Energy Transfer, Jiba Raj Acharya

LSU Doctoral Dissertations

Molecular devices possessing pi-electron conjugated scaffold demonstrate unique capabilities as fluorescent chemosensors for the trace detection of analytes in a variety of environments. Important properties of these compounds such as charge transport and exciton migration, emission intensity etc. can be simply attenuated by external stimuli or analyte binding, leading to considerable changes in observable signals. The main goal of this Ph.D. dissertation was to study the possibility to control excitation energy migration in conjugated systems. Towards this goal, we designed surface-immobilized monodispersed oligo(p-phenylene ethynylene)s (OPEs) as a general basis for thin-film ratiometric fluorescent chemosensors. The sensor molecules have been functionalized …

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A General Approach For Vitrification Of Fish Sperm, Rafael Cuevas Uribe Jan 2011

A General Approach For Vitrification Of Fish Sperm, Rafael Cuevas Uribe

LSU Doctoral Dissertations

The goal of this project was to develop streamlined protocols that could be integrated into a standardized approach for vitrification of germplasm for all aquatic species. Vitrification (freezing by formation of “glass” rather than crystalline ice) is simple, fast, inexpensive, can be potentially used to preserve samples in the field, and offers new options for germplasm management especially appropriate for small fishes. Sperm were studied from freshwater fish (channel catfish Ictalurus punctatus), viviparous freshwater fish (green swordtail Xiphophorus hellerii), and marine fishes (spotted seatrout Cynoscion nebulosus, red snapper Lutjanus campechanus, red drum Sciaenops ocellatus, and southern flounder Paralichthys lethostigma). To …

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Homodyne Detection For Laser-Interferometric Gravitational Wave Detectors, Tobin Thomas Fricke Jan 2011

Homodyne Detection For Laser-Interferometric Gravitational Wave Detectors, Tobin Thomas Fricke

LSU Doctoral Dissertations

Gravitational waves are ripples of space-time predicted by Einstein's theory of General Relativity. The Laser Interferometer Gravitational-wave Observatory (LIGO), part of a global network of gravitational wave detectors, seeks to detect these waves and study their sources. The LIGO detectors were upgraded in 2008 with the dual goals of increasing the sensitivity (and likelihood of detection) and proving techniques for Advanced LIGO, a major upgrade currently underway. As part of this upgrade, the signal extraction technique was changed from a heterodyne scheme to a form of homodyne detection called DC readout. The DC readout system includes a new optical filter …

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Understanding The Selective Detection Of Homocysteine And Studies Toward The Synthesis Of Vinigrol, Dong Wang Jan 2011

Understanding The Selective Detection Of Homocysteine And Studies Toward The Synthesis Of Vinigrol, Dong Wang

LSU Doctoral Dissertations

The first part of the work is dedicated to the selective detection of Homocysteine (Hcy). In order to better understand this colorimetric detection method, a thermodynamic model for the pH dependence of the effective reduction potential of Hcy derived á-carbon radicals has been proposed. And using viologen indicators of varying reduction potentials, we demonstrate that colorimetric changes occur at experimental pH values consistent with the model. The one-carbon bridge stereochemistry of bicyclo[3.3.1]nonane framework is critical to make the third ring of the tricyclic precursor of vinigrol. We studied this stereochemistry carefully and found that the major diastereomer formed from Robinson …

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Oblivious Buy-At-Bulk Network Design Algorithms, Srivathsan Srinivasagopalan Jan 2011

Oblivious Buy-At-Bulk Network Design Algorithms, Srivathsan Srinivasagopalan

LSU Doctoral Dissertations

Large-scale networks such as the Internet has emerged as arguably the most complex distributed communication network system. The mere size of such networks and all the various applications that run on it brings a large variety of challenging problems. Similar problems lie in any network - transportation, logistics, oil/gas pipeline etc where efficient paths are needed to route the flow of demands. This dissertation studies the computation of efficient paths from the demand sources to their respective destination(s). We consider the buy-at-bulk network design problem in which we wish to compute efficient paths for carrying demands from a set of …

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Crystal Growth Of Complex Intermetallics In Search For Heavy Electron Systems, Brenton L. Drake Jan 2011

Crystal Growth Of Complex Intermetallics In Search For Heavy Electron Systems, Brenton L. Drake

LSU Doctoral Dissertations

The structural solution and physical property characterization of several Ln-T-Al/Ga and Ln-T-Al-Si contain phases, which include Ln(Cu,Al)12 (Ln = Y, Ce, Pr, Sm, and Yb), Ln(Ag,Al,Si)2 (Ln = Ce and Gd), LnCu2(Al,Si)5 (Ln = La and Ce), Ln(Cu,Al,Ga)13-x (Ln = La, Ce, Pr, and Eu), α and β LnNiGa4 (α Ln = Y and Gd – Yb; β Ln = (Tb – Er)), and Ln4FeGa12 (Ln = Tb – Er) will be presented in this work with an emphasis on crystal growth. The systems cover a large breadth of phase space and serve to illustrate the new and rich chemistry …

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Studies Of Inhomogeneous Superconducting States In Novel Materials, Robert Pearson Beaird Jan 2011

Studies Of Inhomogeneous Superconducting States In Novel Materials, Robert Pearson Beaird

LSU Doctoral Dissertations

I provide detailed studies of two types of novel superconducting systems. In the first, I examine the effect of thermal (Gaussian) magnetic fluctuations on the superconducting transition of paramagnetically-limited superconductors under a Zeeman magnetic field. I consider transitions into both the uniform and the modulated (Fulde-Ferrell-Larkin-Ovchinnikov) superconducting states. I derive the Landau free energy expansion in powers of the superconducting order parameter, allowing for competition between the magnetic fluctuations and the superconducting order. I determine the order of the transition at the upper critical field and find that the fluctuations drive the transition, usually second-order, to first order at intermediate …

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Excluded-Minor Characterization Of Apex-Outerplanar Graphs, Stanislaw Dziobiak Jan 2011

Excluded-Minor Characterization Of Apex-Outerplanar Graphs, Stanislaw Dziobiak

LSU Doctoral Dissertations

It is well known that the class of outerplanar graphs is minor-closed and can be characterized by two excluded minors: K_4 and K_{2,3}. The class of graphs that contain a vertex whose removal leaves an outerplanar graph is also minor-closed. We provide the complete list of 57 excluded minors for this class.

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Advanced Semantics For Accelerated Graph Processing, Dylan Thomas Stark Jan 2011

Advanced Semantics For Accelerated Graph Processing, Dylan Thomas Stark

LSU Doctoral Dissertations

Large-scale graph applications are of great national, commercial, and societal importance, with direct use in fields such as counter-intelligence, proteomics, and data mining. Unfortunately, graph-based problems exhibit certain basic characteristics that make them a poor match for conventional computing systems in terms of structure, scale, and semantics. Graph processing kernels emphasize sparse data structures and computations with irregular memory access patterns that destroy the temporal and spatial locality upon which modern processors rely for performance. Furthermore, applications in this area utilize large data sets, and have been shown to be more data intensive than typical floating-point applications, two properties that …

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Evolution Of Structural And Physical Properties Of Transition Metal Oxide Sr₃(Ru₁₋Xmnx)₂O₇ (0 <̲ X >̲ 0.7) With Mn Concentration, Biao Hu Jan 2011

Evolution Of Structural And Physical Properties Of Transition Metal Oxide Sr₃(Ru₁₋Xmnx)₂O₇ (0 <̲ X >̲ 0.7) With Mn Concentration, Biao Hu

LSU Doctoral Dissertations

Correlated Electron Materials (CEMs) have attracted the attention of the materials community because the strong coupling between charge, lattice, orbital, and spin degrees of freedom produces exotic phenomena. Transition metal oxide series Srn+1RunO3n+1 (n = 1 to ∞) is a prototype of CEMs. The n = 2 member of this family Sr3Ru2O7 is the subject of this dissertation. It has a paramagnetic (PM) metallic ground state, which can be driven into an antiferromagnetic (AFM) insulator with a partial substitution of Ru by Mn. The focus of this research is to understand the role of chemical doping as the driving force …

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Paley-Wiener Theorems With Respect To The Spectral Parameter, Susanna Dann Jan 2011

Paley-Wiener Theorems With Respect To The Spectral Parameter, Susanna Dann

LSU Doctoral Dissertations

One of the important questions related to any integral transform on a manifold M or on a homogeneous space G/K is the description of the image of a given space of functions. If M=G/K, where (G,K) is a Gelfand pair, then harmonic analysis on M is closely related to the representations of G and the direct integral decomposition of L^2(M) into irreducible representations of G. R^n can be realized as the quotient R^n=E(n)/SO(n), where E(n) is the orientation preserving Euclidean motion group. The pair (E(n), SO(n)) is a Gelfand pair. Hence this realization of R^n comes with its own natural …

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Numerical Methods For The Study Of Super-Eddington Mass Transfer In Double White Dwarf Binaries, Dominic Carlo Marcello Jan 2011

Numerical Methods For The Study Of Super-Eddington Mass Transfer In Double White Dwarf Binaries, Dominic Carlo Marcello

LSU Doctoral Dissertations

We present a numerical method for the study of double white dwarf (DWD) binary systems at the onset of super-Eddington mass transfer. We incorporate the physics of ideal inviscid hydrodynamical flow, Newtonian self-gravity, and radiation transport on a three-dimensional uniformly rotating cylindrical Eulerian grid. Our new method conserves total energy to a higher degree of accuracy than recent smoothed particle hydrodynamics methods and our previous Eulerian grid based method. We present the results of verification tests and we simulate the first 20+ orbits of a binary system of mass ratio q=0.7 at the onset of dynamically unstable direct impact mass …

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Data-Aware Workflow Scheduling In Heterogeneous Distributed Systems, Dengpan Yin Jan 2011

Data-Aware Workflow Scheduling In Heterogeneous Distributed Systems, Dengpan Yin

LSU Doctoral Dissertations

Data transferring in scientific workflows gradually attracts more attention due to large amounts of data generated by complex scientific workflows will significantly increase the turnaround time of the whole workflow. It is almost impossible to make an optimal or approximate optimal scheduling for the end-to-end workflow without considering the intermediate data movement. In order to reduce the complexity of the workflow-scheduling problem, most researches done so far are constrained by many unrealistic assumptions, which result in non-optimal scheduling in practice. A constraint imposed by most researchers in their algorithms is that a computation site can only start the execution of …

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Quantitative Mapping Of Cyanobacterial Blooms Using Oceansat-1 Ocm Satellite Data, Padmanava Dash Jan 2011

Quantitative Mapping Of Cyanobacterial Blooms Using Oceansat-1 Ocm Satellite Data, Padmanava Dash

LSU Doctoral Dissertations

Cyanobacteria represent a major harmful algal group in fresh to brackish water environments. Lac des Allemands, a freshwater lake of 49 km2 southwest of New Orleans, Louisiana, provides a natural laboratory for remote characterization of cyanobacteria blooms because of their seasonal occurrence. This dissertation makes a contribution to research methodology pertaining to atmospheric correction of satellite data and development of remote sensing algorithms to quantify cyanobacterial pigments. The Ocean Color Monitor (OCM) sensor provides radiance measurements similar to Sea-viewing Wide Field-of-View Sensor (SeaWiFS) but with higher spatial resolution. However, OCM does not have a standard atmospheric correction procedure and …

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Analysis Of Amyloid Beta (A [Beta]) Peptides By Capillary Electrophoresis And Laser-Induced Fluorescence Anisotropy Detection, Ryan Andrew Picou Jan 2011

Analysis Of Amyloid Beta (A [Beta]) Peptides By Capillary Electrophoresis And Laser-Induced Fluorescence Anisotropy Detection, Ryan Andrew Picou

LSU Doctoral Dissertations

The goal of the research presented in this dissertation is to develop laser-induced fluorescence anisotropy (LIFA) detection for detecting and characterizing amyloid beta (Aβ) peptide aggregates separated by capillary electrophoresis (CE). Senile plaques composed primarily of aggregated Aβ (1-40) and Aβ (1-42) peptides have been found in the brains of Alzheimer’s disease patients. These peptides are thought to be responsible for the disease pathology. A CE method using UV absorbance detection was developed for the quantification of Aβ (1-40) monomer and testing of Aβ monomer preparations for undesired aggregates (Chapter 2). Analyses of both Aβ (1-40) and Aβ (1-42) monomer …

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Fabrication Of Organosilane Nanostructures As Selective Sites For Surface Chemical Reactions, Kathie Lee Lusker Jan 2011

Fabrication Of Organosilane Nanostructures As Selective Sites For Surface Chemical Reactions, Kathie Lee Lusker

LSU Doctoral Dissertations

Naturally self-assembled mesospheres provide a practical route for controlling the arrangement of materials on surfaces at the nanoscale. Periodic arrays of well-defined nanostructures can be produced with different nanomaterials and interpattern spacings. Results presented in this dissertation demonstrate particle lithography methods developed for fabricating arrays of organosilane nanostructures. Surfaces were designed for the selective deposition of polymers and nanoparticles to produce multicomponent nanopatterns. The approaches for surface patterning provide new directions for studying surface chemistry at the molecular-level, and have practical application for emerging photovoltaic thin film technologies. Atomic force microscopy (AFM) provides unique capabilities for molecular visualization and ultrasensitive …

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Surface-Initiated Polymerization As A Novel Strategy Towards Preparation Of Organic Semiconducting Polymer Thin Films, Euiyong Hwang Jan 2011

Surface-Initiated Polymerization As A Novel Strategy Towards Preparation Of Organic Semiconducting Polymer Thin Films, Euiyong Hwang

LSU Doctoral Dissertations

Organic semiconducting polymer thin films are core materials for organic electronics that are conventionally prepared by solution processing techniques. Despite having the advantage of easy and fast thin film manufacturing, solution techniques have intrinsic drawbacks, such as disordered and poor molecular organization in the film (often resulting in poor device performance), as well as insufficient stabilities of the films and resulting devices. To improve this situation, we designed a novel “bottom-up” fabrication of surface-immobilized organic semiconducting thin films through in situ polymerization. This new strategy will allow high degree of control over molecular organization which therefore results in improved free …

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A Comprehensive Study Of Dust Formation And Evolution In Core Collape Supernovae, Jennifer Erin Andrews Jan 2011

A Comprehensive Study Of Dust Formation And Evolution In Core Collape Supernovae, Jennifer Erin Andrews

LSU Doctoral Dissertations

Detection of large amounts of dust in high redshift galaxies suggests that core collapse supernovae (CCSNe) may play a critical role in the dust budget of galaxies in the early universe, when galaxies are only a few hundred million years old. At an age of only 1Gyr, asymptotic giant branch (AGB) stars may not have had the time to become significant dust contributors, leaving CCSNe as an alternative explanation since they quickly evolve and return their material to the surrounding interstellar medium. For the past three years, I have been observing the CCSNe 2007it and 2007od with Gemini, Hubble Space …

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Characterization Of Photon Counting Czt Detectors For Medical X-Ray Imaging And Spectroscopy, Shannon Fritz Jan 2011

Characterization Of Photon Counting Czt Detectors For Medical X-Ray Imaging And Spectroscopy, Shannon Fritz

LSU Doctoral Dissertations

Purpose: The purpose of this research was to characterize a photon counting cadmium zinc telluride (CZT) detector for medical x-ray imaging and spectroscopy purposes. The overall aim was to characterize CZT detector properties and to develop modifications and correction methods to address the limiting factors, making the detector clinically viable. Methods: Hole trapping issues were investigated through simulation and experiments with a large area single pixel CZT detector under three different irradiation geometries: edge-on, surface-on, and tilted angle irradiation. Characteristic x-ray escape was simulated using Monte Carlo methods and compared to measurements with a small pixel CZT imaging detector. Monoenergetic …

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A C0 Interior Penalty Method For The Von Kármán Equations, Armin Karl Reiser Jan 2011

A C0 Interior Penalty Method For The Von Kármán Equations, Armin Karl Reiser

LSU Doctoral Dissertations

In this dissertation we develop a C0 interior penalty method for the von Kármán equations for nonlinear elastic plates. We begin with a brief survey on frequently used finite element methods for the von Kármán equations. After addressing some topics from functional analysis in the preliminaries, we present existence, uniqueness and regularity results for the solutions of the von Kármán equations in Chapter 3. In the next chapter we review the C0 interior penalty method for the biharmonic problem. Motivated by these results, we propose a C0 interior penalty method for the linearized von Kármán equations in …

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Proteomic Analysis Of The Blood Of Alligator Mississippiensis, Lancia Nadinia Fallen Darville-Bowleg Jan 2011

Proteomic Analysis Of The Blood Of Alligator Mississippiensis, Lancia Nadinia Fallen Darville-Bowleg

LSU Doctoral Dissertations

My research focus was to investigate alligator blood using mass spectrometry-based proteomics methods to understand their innate immune systems. The first goal was to sequence peptides and proteins from the blood serum and leukocytes using tandem mass spectrometry and de novo sequencing. The second goal was to determine the function of these biological molecules and their relationship to the immune system. One- and two-dimensional gel electrophoresis was used to separate proteins from alligator leukocytes, which were enzymatically digested. The peptides were measured using reversed phase nano-high performance liquid chromatography coupled with tandem mass spectrometry (nano-HPLC-MS/MS) followed with de novo sequencing. …

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Structural And Electronic Properties Of Noble Metals On Metal Oxide Surfaces, Fei Wang Jan 2011

Structural And Electronic Properties Of Noble Metals On Metal Oxide Surfaces, Fei Wang

LSU Doctoral Dissertations

Noble metals on metal oxide surfaces play crucial roles in many catalysis applications. Due to extreme complexity of the interfaces and catalytic reaction processes, basic science studies of model systems are needed to guide the construction and optimization of new industrial catalysts. We have employed ultra-high vacuum techniques to investigate the morphology, electronic structure, and surface reactivations of clean metal-oxide/metal nanocluster interfaces in ideal conditions. The systems we chose are Ag/TiO2, a popular photocatalyst, and Cu/ZnO, recently a hot candidate for liquid fuel production. The main characterization techniques that we have employed include Scanning Tunneling Microscopy (STM), Photoemission Spectroscopy (PES), …

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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. …

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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, …

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