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Synthesis Of A Dirhodium Tetraphosphine Catalyst And The Effect Of Various H2/Co Ratios On The Catalyst, Christina Joanne Sweeney Dec 2008

Synthesis Of A Dirhodium Tetraphosphine Catalyst And The Effect Of Various H2/Co Ratios On The Catalyst, Christina Joanne Sweeney

Honors Theses

No abstract provided.


Empirical Study On Greedy Algorithms For Learning Decomposable Markov Networks, Kyle Jonah Nunez Aug 2008

Empirical Study On Greedy Algorithms For Learning Decomposable Markov Networks, Kyle Jonah Nunez

Honors Theses

No abstract provided.


Carbon, Nitrogen, Sodium And Phosphorous Concentrations And Ratios In Spartina Alterniflora (Loiser) From Sites Of Various Freshwater And Nutrient Inputs In Coastal Louisiana Wetlands, Margaret Frances Williamson May 2008

Carbon, Nitrogen, Sodium And Phosphorous Concentrations And Ratios In Spartina Alterniflora (Loiser) From Sites Of Various Freshwater And Nutrient Inputs In Coastal Louisiana Wetlands, Margaret Frances Williamson

Honors Theses

No abstract provided.


The Determination Of The Electronic Structure And Geometries Of Boron And Boron Mononitrogen Clusters Using An Adaptive, Kink-Based Path Integral Approach To Quantum Mechanics, Shawn Wilkinson May 2008

The Determination Of The Electronic Structure And Geometries Of Boron And Boron Mononitrogen Clusters Using An Adaptive, Kink-Based Path Integral Approach To Quantum Mechanics, Shawn Wilkinson

Honors Theses

No abstract provided.


Preconditioned Conjugate Gradient Algorithm, Elena Caraba Mar 2008

Preconditioned Conjugate Gradient Algorithm, Elena Caraba

Honors Theses

No abstract provided.


Searching For Gravitational Waves From Binary Systems In Non-Stationary Data, Chad Hanna Jan 2008

Searching For Gravitational Waves From Binary Systems In Non-Stationary Data, Chad Hanna

LSU Doctoral Dissertations

The gravitational wave detectors at the LIGO Observatories have achieved record sensitivity to gravitational-waves produced by astrophysical systems. The LIGO Scientific Collaboration has analyzed data taken in several science runs, searching for different signals. We describe a search for black holes with less than a solar mass in the LIGO data taken from February 22 to March 24, 2005. No gravitational waves were found, and an upper limit was set on the rate of mergers of such binary systems. This search, as well as other searches for binary systems, are affected by non-stationary noise. We describe the sophisticated pipeline that …


Investigation Of Antimonide Structure Types And The Structural Studies Of Molybdates, Dixie Plaisance Gautreaux Jan 2008

Investigation Of Antimonide Structure Types And The Structural Studies Of Molybdates, Dixie Plaisance Gautreaux

LSU Doctoral Dissertations

This dissertation highlights the investigation of ternary lanthanide antimonide structure types and their physical properties. In particular, these ternary phases allow for the systematic investigation of the structure in an effort to correlate structure and properties. The ternary antimonides are layered structures with two-dimensional square sheets or nets, which influence the properties of these materials. In an effort to determine how structural changes influence the physical properties, various single crystals of compounds relating to the orthorhombic CeNiSb3 structure have been grown and characterized. The layered CeNiSb3 structure consists of Sb sheets, NiSb6 distorted octahedra, and CeSb9 monocapped square anti-prisms. LnNi(Sn,Sb)3 …


Rational Approximation Schemes For Solutions Of Abstract Cauchy Problems And Evolution Equations, Patricio Gabriel Jara Jan 2008

Rational Approximation Schemes For Solutions Of Abstract Cauchy Problems And Evolution Equations, Patricio Gabriel Jara

LSU Doctoral Dissertations

In this dissertation we study time and space discretization methods for approximating solutions of abstract Cauchy problems and evolution equations in a Banach space setting. Two extensions of the Hille-Phillips functional calculus are developed. The first result is the Hille-Phillips functional calculus for generators of bi-continuous semigroups, and the second is a C-regularized version of the Hille-Phillips functional calculus for generators of C-regularized semigroups. These results are used in order to study time discretization schemes for abstract Cauchy problems associated with generators of bi-continuous semigroups as well as C-regularized semigoups. Stability, convergence results, and error estimates for rational approximation schemes …


Space-Time Multiresolution Approach To Atomistic Visualization, Dipesh Bhattarai Jan 2008

Space-Time Multiresolution Approach To Atomistic Visualization, Dipesh Bhattarai

LSU Doctoral Dissertations

Time-varying three-dimensional positional atomistic data are rich in spatial and temporal information. The problem is to understand them. This work offers multiple approaches that enable such understanding. An interactive atomistic visualization system is developed integrating complex analyses with visualization to present the data on space-time multiresolution basis facilitating the information extraction and generate understanding. This work also shows the usefulness of such an integrated approach. The information obtained from the analyses represents the system at multiple length and time scales. Radial distribution function (RDF) provides a complete average spatial map of the distribution of the atoms in the system which …


Evidence For Symplectic Symmetry In Ab Initio No-Core Shell Model Results, Tomas Dytrych Jan 2008

Evidence For Symplectic Symmetry In Ab Initio No-Core Shell Model Results, Tomas Dytrych

LSU Doctoral Dissertations

Advances in the construction of realistic internucleon interactions together with the advent of massively parallel computers have resulted in a successful utilization of the ab initio approaches to the investigation of properties of light nuclei. The no-core shell model is a prominent ab initio method that yields a good description of the low-lying states in few-nucleon systems as well as in more complex p-shell nuclei. Nevertheless, its applicability is limited by the rapid growth of the many-body basis with larger model spaces and increasing number of nucleons. To extend the scope of the ab initio no-core shell model to heavier …


The Synthesis Of Water Soluble N-Acyl Chitosan Derivatives For Characterization As Antibacterial Agents, Lakia Monique Champagne Jan 2008

The Synthesis Of Water Soluble N-Acyl Chitosan Derivatives For Characterization As Antibacterial Agents, Lakia Monique Champagne

LSU Doctoral Dissertations

Currently, natural polysaccharides are being utilized increasingly in the markets because they exhibit biodegradability, biocompatibility, versatility, and are found abundant in nature. The diversity of natural polysaccharides provides the chemist with a broad spectrum of raw materials that can be used in many biological applications. Chitosan is a natural polysaccharide that possesses excellent biological properties. It has been recognized for its antibacterial activity, in that it is destructive towards the bacterium Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The antibacterial property of chitosan can be enhanced by changing the hydrophobic/hydrophilic nature of the polysaccharide backbone. This research entails …


Surgery Description Of Colored Knots, Steven Daniel Wallace Jan 2008

Surgery Description Of Colored Knots, Steven Daniel Wallace

LSU Doctoral Dissertations

By a knot, or link, we mean a circle, or a collection of circles, embedded in the three-sphere S3. The study of knots is a very rich subject and plays a key role in the area of low-dimensional topology. In fact, a theorem of W.B.R. Lickorish and A.D. Wallace states that any three-dimensional manifold may be described by Dehn surgery along a link which is the process of removing the link from S3 and then gluing it back in a way that possibly changes the resulting manifold. In this dissertation, we will be interested in the pair (K, ρ) consisting …


Identification Of Quantitative Trait Loci Influencing Early Height Growth In Longleaf Pine (Pinus Palustris Mill), Lisha Wu Jan 2008

Identification Of Quantitative Trait Loci Influencing Early Height Growth In Longleaf Pine (Pinus Palustris Mill), Lisha Wu

LSU Doctoral Dissertations

The delay in early height growth (EHG) has been a limiting factor for artificial regeneration of longleaf pine (Pinus palustris Mill.). Simple Sequence Repeat (SSR) markers have been used to map the genome and quantitative trait loci controlling the EHG in a backcross family (longleaf pine x slash pine) x longleaf pine. A total of 228 locus specific SSR markers were screened against 6 longleaf pine recurrent parents and a sample of 7 longlef x slash pine hybrid parents. In total, 135 polymorphic markers were identified. Based on the genetic variance in EHG, available sample size, and the number of …


Synthesis And Surface Characterization Of Silica-Polypeptide Composite Particles, Erick Isael Soto-Cantu Jan 2008

Synthesis And Surface Characterization Of Silica-Polypeptide Composite Particles, Erick Isael Soto-Cantu

LSU Doctoral Dissertations

The synthesis and sequential surface characterization of silica-polypeptide composite particles is described. Nearly monodisperse colloidal silica cores were obtained by the alkaline hydrolysis of tetraethyl orthosilicate (TEOS). The hydrodynamic radius can be easily controlled in the range of ƒî 20-140 nm by the water/TEOS ratio in the starting reaction mixture. The surface of the synthesized silica cores was further passivated/functionalized (P/F) by a mixture of (3-aminopropyl) trimethoxysilane (APS) and methyl-trimethoxysilane (MTMS). The amino groups were quantified using UV-Vis spectrometry after reaction with ninhydrin. The use of zeta potential measurements of the P/F silica particles at low pH is presented as …


Rice Straw Fiber Polymer Composites: Thermal And Mechanical Performance, Fei Yao Jan 2008

Rice Straw Fiber Polymer Composites: Thermal And Mechanical Performance, Fei Yao

LSU Doctoral Dissertations

Rice straw fiber can be considered as important potential reinforcing filler for thermoplastic composite because of its lignocellulosic characteristics. It is thus of practical significance to understand and predict the thermal decomposition process of rice straw fibers. A method proposed by Málek, Šesták, and co-workers was used to investigate and model thermal decomposition process of common natural fibers with detailed analysis on rice straw system. Assuming a global model occurring within the entire degradation of natural fibers with consideration of fiber as one pseudo-component, model can be used to describe both isothermal and non-isothermal degradation process of most selected fibers …


Solid-Phase Synthesis Of Asymmetrically Substituted Phthalocyanines, Sultan Sibel Erdem Jan 2008

Solid-Phase Synthesis Of Asymmetrically Substituted Phthalocyanines, Sultan Sibel Erdem

LSU Doctoral Dissertations

Phthalocyanines (Pcs) are excellent candidates for use as fluorophores for near-infrared (near-IR) fluorescent tagging of biomolecules and as photodynamic therapy (PDT) agents. Synthesis of Pcs with asymmetrical substitution on the periphery is often difficult due to the problems during the purification of the Pc mixtures obtained. The objective of this project is to design and synthesize chemically robust near-IR fluorophores for bioanalytical applications and to develop new synthetic methods for rapid synthesis of the target compounds. A novel synthetic route was developed utilizing a hydrophilic, polyethylene glycol-based (PEG) support with different types of linkers. The Pcs were functionalized with either …


Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry For The Analysis Of Collected Bioaerosols, Alton John Dugas Jan 2008

Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry For The Analysis Of Collected Bioaerosols, Alton John Dugas

LSU Doctoral Dissertations

The goal of this dissertation was to demonstrate collection, detection and identification of microorganisms from bioaerosols using offline matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) for the analysis of proteins. MALDI-MS intact bacteria techniques were adapted for use with an orthogonal MALDI quadrupole-time-of-flight mass spectrometer. Results indicate the instrument is capable of analyzing intact whole-cells. The first phase was to evaluate three bioaerosol samplers, an Andersen N6 single-stage impactor (AI), a cyclone impactor, and a vacuum filter system. The samplers collected test bioaerosols using a constructed bioaerosol exposure chamber (BEC). The BEC allowed all three samplers to operate in parallel. Each …


Limit On The Muon Neutrino Magnetic Moment And A Measurement Of The Ccpip To Ccqe Cross Section Ratio, Serge Arisitde Ouedraogo Jan 2008

Limit On The Muon Neutrino Magnetic Moment And A Measurement Of The Ccpip To Ccqe Cross Section Ratio, Serge Arisitde Ouedraogo

LSU Doctoral Dissertations

A search for the muon neutrino magnetic moment was conducted using the Mini- BooNE low energy neutrino data. The analysis was performed by analyzing the elastic scattering interactions of muon neutrinos on electrons. The analysis looked for an excess of elastic scattering events above the Standard Model prediction from which a limit on the neutrino magnetic could be set. In this thesis, we report an excess of 15.3}6.6(stat)}4.1(syst) elastic scattering events above the expected background. At 90% C.L., we derived a limit on the muon neutrino magnetic moment of 12.7~ 10−10ƒÊB. The other analysis reported in this thesis is a …


A Novel Automated Approach Of Multi-Modality Retinal Image Registration And Fusion, Hua Cao Jan 2008

A Novel Automated Approach Of Multi-Modality Retinal Image Registration And Fusion, Hua Cao

LSU Doctoral Dissertations

Biomedical image registration and fusion are usually scene dependent, and require intensive computational effort. A novel automated approach of feature-based control point detection and area-based registration and fusion of retinal images has been successfully designed and developed. The new algorithm, which is reliable and time-efficient, has an automatic adaptation from frame to frame with few tunable threshold parameters. The reference and the to-be-registered images are from two different modalities, i.e. angiogram grayscale images and fundus color images. The relative study of retinal images enhances the information on the fundus image by superimposing information contained in the angiogram image. Through the …


Effects Of Burning On Henslow's Sparrow (Ammodramus Henslowii) Density And Habitat Quality In Louisiana, Laura M. Palasz Jan 2008

Effects Of Burning On Henslow's Sparrow (Ammodramus Henslowii) Density And Habitat Quality In Louisiana, Laura M. Palasz

LSU Master's Theses

The Henslow’s Sparrow (Ammodramus henslowii) is a grassland species of concern that winters in prairies and open pine savannas across the Gulf Coastal Plain. Previous studies have indicated that these birds occur at higher densities in recently burned habitats in winter, but this has never been examined over a large geographic area containing multiple habitat types. The objectives of the study were to identify areas of important winter habitat in Louisiana, to examine the relationship between time since burn, bird density, and bird condition, and to determine vegetation structure and composition used by birds. We found most of the new …


Computed Tomography Imaging To Quantify Iodine Distribution In Iododeoxyuridine-Labeled Dna, Christopher Erik Welch Jan 2008

Computed Tomography Imaging To Quantify Iodine Distribution In Iododeoxyuridine-Labeled Dna, Christopher Erik Welch

LSU Master's Theses

Purpose: Treatment planning for x-ray activated Auger electron radiotherapy requires knowledge of the spatial distribution of Auger electron-producing target atoms in DNA; iodine is a candidate atom. Because planning uses computed tomography (CT) data to show anatomy, obtaining the target atoms' distribution with CT methods is an attractive goal. This study evaluates the ability of two available CT systems to measure the target atoms' spatial distribution. Method and Materials: A polychromatic desktop CT scanner and a synchrotron monochromatic CT system acquired images of iodine concentrations in water, ranging from 0.03-10 mg/ml. The polychromatic scanner was operated at 40 kVp while …


Land Use And Water Quality Characterization Of Boeuf Basin, La, Joseph Wesley Leblanc Jan 2008

Land Use And Water Quality Characterization Of Boeuf Basin, La, Joseph Wesley Leblanc

LSU Master's Theses

The three primary goals of this project were to establish the ambient background of water quality in the Lake Boeuf basin in southeast Louisiana; establish land use patterns in the basin and the relation to water quality; and develop a preliminary plan to improve water quality through the use of best management practices and wetland assimilation. Urban and agricultural acreage borders the basin and runoff from these lands forces loadings of nutrients into the adjacent canals where they become channelized and ultimately exit the Boeuf Basin into Lac des Allemandes. From September 2007 until February 2008, water sampling occurred monthly …


Growth And Properties Of Metal-On-Metal Nanostructures: Ag On Cu(110) And Co On Ag(110), Indrajith Chandima Senevirathne Jan 2008

Growth And Properties Of Metal-On-Metal Nanostructures: Ag On Cu(110) And Co On Ag(110), Indrajith Chandima Senevirathne

LSU Doctoral Dissertations

Heteroepitaxial nanostructures have a diverse array of applications and show novel phenomena that arise from the exotic physics exhibited in reduced dimensions. We have investigated two nano-structured systems in order to gain insights into the dynamics of their nucleation, growth and have observed striking differences, due in part to a competition between lattice strain, surface and interfacial free energies. When Ag is deposited on clean, single-crystal Cu(110), it initially wets the surface with a (111) monolayer, and spontaneously nucleates nanowires as the coverage is increased. The nanowires nucleate at defects and step edges and grow aligned along the [1–10] direction. …


Chemical Analysis Of Polymer Blends Via Synchrotron X-Ray Tomography, Heath Alan Barnett Jan 2008

Chemical Analysis Of Polymer Blends Via Synchrotron X-Ray Tomography, Heath Alan Barnett

LSU Doctoral Dissertations

Material properties of industrial polymer blends are of great importance. X-ray tomography has been used to obtain spatial chemical information about various polymer blends. The spatial images are acquired with synchrotron X-ray tomography because of its rapidity, good spatial resolution, large field-of-view, and elemental sensitivity. The spatial absorption data acquired from X-ray tomography experiments is converted to spatial chemical information via a linear least squares fit of multi-spectral X-ray absorption data. A fiberglass-reinforced polymer blend with a new-generation flame retardant is studied with multi-energy synchrotron X-ray tomography to assess the blend homogeneity. Relative to other composite materials, this sample is …


Syntheses Of Trimethylamine- And Phosphonate- Substituted Carboranylporphyrins For Application In Boron Neutron Cancer Therapy, Michael William Easson Jan 2008

Syntheses Of Trimethylamine- And Phosphonate- Substituted Carboranylporphyrins For Application In Boron Neutron Cancer Therapy, Michael William Easson

LSU Doctoral Dissertations

Chapter 1 contains an introduction to porphyrins and carboranylporphyrins, including their physical properties, history, methods of synthesis, medicinal applications, and an overview of recently published compounds. Chapter 2 contains the total synthesis of a series of trimethylamine- and phosphonate-substituted carboranylporphyrins for application in boron neutron capture therapy (BNCT), including characterization by proton nuclear magnetic resonance spectroscopy, matrix-assisted time-of-flight mass spectroscopy, high resolution mass spectroscopy, UV-Vis spectrophotometry, X-ray crystallography, and melting point apparatus. Chapter 3 contains synthetic methods which were investigated as alternate routes to porphyrin synthesis and functionalization. Chapter 4 presents the in vitro biological evaluation of trimethylamine- and phosphonate-substituted …


Visual Language Representation For Use Case Evolution And Traceability, Coretta Willis Douglas Jan 2008

Visual Language Representation For Use Case Evolution And Traceability, Coretta Willis Douglas

LSU Doctoral Dissertations

The primary goal of this research is to assist non-technical stakeholders involved in requirements engineering with a comprehensible method for managing changing requirements within a specific domain. An important part of managing evolving requirements over time is to maintain a temporal ordering of the changes and to support traceability of the modifications. This research defines a semi-formal syntactical and semantic definition of such a method using a visual language, RE/TRAC (Requirements Evolution with Traceability), and a supporting formal semantic notation RE/TRAC-SEM. RE/TRAC-SEM is an ontological specification employing a combination of models, including verbal definitions, set theory and a string language …


Non-Industrial Private Forest Landowners And Us Home Center Retailers' Attitudes And Perceptions Of Forest Certification, Polwattage Kushil Perera Jan 2008

Non-Industrial Private Forest Landowners And Us Home Center Retailers' Attitudes And Perceptions Of Forest Certification, Polwattage Kushil Perera

LSU Master's Theses

The concept of forest certification, a relatively recent development in forestry, is based on the use of market-based incentives to encourage sustainable forest management practices. Since the majority of forests in US South are privately owned, certifying forests owned by non-industrial private forest (NIPF) landowners is an important issue. From the demand perspective of certification, pressure from non-governmental environmental organizations and consumer awareness has prompted major wood products retailers to state preferences for certified wood products. In the US, wood product demand in the retail home centers sector is second only to the home building industry. In addition, home center …


Fast Marching Methods - Parallel Implementation And Analysis, Maria Cristina Tugurlan Jan 2008

Fast Marching Methods - Parallel Implementation And Analysis, Maria Cristina Tugurlan

LSU Doctoral Dissertations

Fast Marching represents a very efficient technique for solving front propagation problems, which can be formulated as partial differential equations with Dirichlet boundary conditions, called Eikonal equation: $F(x)|\nabla T(x)|=1$, for $x \in \Omega$ and $T(x)=0$ for $x \in \Gamma$, where $\Omega$ is a domain in $\mathbb{R}^n$, $\Gamma$ is the initial position of a curve evolving with normal velocity F>0. Fast Marching Methods are a necessary step in Level Set Methods, which are widely used today in scientific computing. The classical Fast Marching Methods, based on finite differences, are typically sequential. Parallelizing Fast Marching Methods is a step forward for …


Effect Of Hydrology On The Structure And Function Of Mangrove Ecosystems In The Can Gio Mangrove Biosphere Reserve, Vietnam, Loi Tan Le Jan 2008

Effect Of Hydrology On The Structure And Function Of Mangrove Ecosystems In The Can Gio Mangrove Biosphere Reserve, Vietnam, Loi Tan Le

LSU Doctoral Dissertations

The influence of hydrology on the mangrove forests of Vietnam has received little scientific attention, even though hydrology is recognized as the primary forcing function in mangrove ecosystems worldwide. The purpose of this dissertation research was to determine the effects of hydrology on specific structural attributes and functional processes within the mangrove forests of Can Gio, a province in southeastern Vietnam. Khe Vinh (KV) and Mui O (MO), two locations within compartment 17 of the Can Gio Mangrove Biosphere Reserve, were chosen as study sites. This research addressed two questions: (1) What are the characteristics of the hydrological regime at …


Komatiitic Flows Of The Pioneer Ultramafic Complex Of The 3.3ga Weltevreden Formation, Barberton Greenstone Belt, South Africa: Stratigraphy, Petrology, And Geochemistry, Marc Romain Cooper Jan 2008

Komatiitic Flows Of The Pioneer Ultramafic Complex Of The 3.3ga Weltevreden Formation, Barberton Greenstone Belt, South Africa: Stratigraphy, Petrology, And Geochemistry, Marc Romain Cooper

LSU Master's Theses

The 3.29 Ga Pioneer Ultramafic Complex (WPC) is a 1 km thick east-northeast trending tilted (90° dip) section of layered ultramafic rock in the Weltevreden Formation in the west-northwest region of the Barberton Greenstone Belt (BGB). It was originally interpreted as an intrusive complex with slaty zones that have a linear horizontal fabric produced by shear. However, a recent study identifies these slaty zones as komatiitic tuffs and attributes their horizontal fabric to plane and cross bedding. The present study suggests the non-slaty zones are extrusive komatiitic flows with abundant pyroxene spinifex tops, normal volcanic textures and crystal sizes, and …