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LSU Doctoral Dissertations

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Integrating Micro-Scale Separations To Matrix Assisted Laser Desorption And Ioniation Time Of Flight Mass Spectrometry (Maldi-Tof-Ms) For Protein Analysis, Harrison K. Musyimi Jan 2006

Integrating Micro-Scale Separations To Matrix Assisted Laser Desorption And Ioniation Time Of Flight Mass Spectrometry (Maldi-Tof-Ms) For Protein Analysis, Harrison K. Musyimi

LSU Doctoral Dissertations

This dissertation describes the integration of micro-scale separations to matrix assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI TOF MS) for protein analysis. MALDI MS provides unsurpassed accurate mass measurements of intact bio-molecules, for example peptides and proteins, which in turn generate high molecular specificity enabling the identity, function and structure of these molecules to be characterized. However, in order to realize the full potential of MS in proteomic studies, integrated sample processing on automated and high throughput platforms is required to address the complexity, diversity and the dynamic range of proteomic analysis. The work described here contributes towards …

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Direct Detection Of Homocysteine And Syntheses Of Lanthanide Complexes As Biosensors, Weihua Wang Jan 2006

Direct Detection Of Homocysteine And Syntheses Of Lanthanide Complexes As Biosensors, Weihua Wang

LSU Doctoral Dissertations

At elevated levels, homocysteine (Hcy) is a risk factor for cardiovascular diseases and Alzheimer’s disease. It’s also implicated in a number of other diseases such as neural tube defects, pregnancy complications, and renal failures. The monitoring of Hcy levels in plasma is of current concern. To date, the biochemical mechanism by which Hcy is involved in disease states is unclear. Herein, we describe highly selective colorimetric methods for the direct determination of Hcy. Inexpensive, commercially available materials are reported. The results show potential application for the detection of Hcy in human blood plasma. Additionally, new HPLC postcolumn detection methods for …

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Modeling The Effects Of Endocrine Disrupting Chemicals On Atlantic Croaker: Understanding Biomarkers And Predicting Population Responses, Cheryl Anne Murphy Jan 2006

Modeling The Effects Of Endocrine Disrupting Chemicals On Atlantic Croaker: Understanding Biomarkers And Predicting Population Responses, Cheryl Anne Murphy

LSU Doctoral Dissertations

A number of environmental stressors have been shown to interfere with reproductive and behavioral processes of fish by interfering with endocrine function. Most biomarkers of endocrine disturbance tend to be static measurements from dynamic systems making them difficult to evaluate within the context of an individual, or subtle effects that do not relate well to endpoints of ecological significance. I present an approach that uses a series of models, based on Atlantic croaker, to extrapolate laboratory results to indicators of individual and population health. First, I created a physiologically based model that simulates vitellogenesis in a female fish. The model …

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Effects Of An External Field And Dissipation On Decoherence, Jian Zuo Jan 2006

Effects Of An External Field And Dissipation On Decoherence, Jian Zuo

LSU Doctoral Dissertations

Decoherence is the suppression of the interference of quantum states. It plays important roles in the study of the quantum-classical transition. It is also the major obstacle in the implementation of various schemes of quantum computers. Decoherence can be affected by many factors. The interactions between quantum systems of interest and dissipative environments cause the extensively studied environment-induced-decoherence. Decoherence can also occur as the result of a temperature effect. A recent experiment investigated the engineering of decoherence, which involves applying an external field to the quantum system. In this thesis, we study the effect of an external field on decoherence …

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Extension Of Shor's Period-Finding Algorithm To Infinite Dimensional Hilbert Spaces, Jeremy James Becnel Jan 2006

Extension Of Shor's Period-Finding Algorithm To Infinite Dimensional Hilbert Spaces, Jeremy James Becnel

LSU Doctoral Dissertations

Over the last decade quantum computing has become a very popular field in various disciplines, such as physics, engineering, and mathematics. Most of the attraction stemmed from the famous Shor period--finding algorithm, which leads to an efficient algorithm for factoring positive integers. Many adaptations and generalizations of this algorithm have been developed through the years, some of which have not been ripened with full mathematical rigor. In this dissertation we use concepts from white noise analysis to rigorously develop a Shor algorithm adapted to find a hidden subspace of a function with domain a real Hilbert space. After reviewing the …

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Factors That Influence Traditional-Age, High-Achieving Students To Enroll At A Research-Extensive University In The Southern Region Of The United States, Roy Cleveland Brooks, Jr. Jan 2006

Factors That Influence Traditional-Age, High-Achieving Students To Enroll At A Research-Extensive University In The Southern Region Of The United States, Roy Cleveland Brooks, Jr.

LSU Doctoral Dissertations

The primary purpose of this study was to determine if a model existed that significantly increased the researcher's ability to accurately explain the enrollment status of high-achieving freshmen based on the influence of selected demographic and academic characteristics. Since World War II, the need for students to obtain an outstanding postsecondary education in order to compete for the best positions in today's job market has become increasingly important. Thus, the need exists for higher education institutions to offer competitive academic programs that will attract top students and faculty. Since the number of graduating high school students is predicted to decline …

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Quantifying Changes In Fish Habitat Use In Coastal Waters Of Louisiana, Usa: A Hydroacoustic Approach, Kevin Mershon Boswell Jan 2006

Quantifying Changes In Fish Habitat Use In Coastal Waters Of Louisiana, Usa: A Hydroacoustic Approach, Kevin Mershon Boswell

LSU Doctoral Dissertations

The development of reliable tools for identifying essential fish habitat (EFH) has proven problematic. Knowledge of the distribution and biomass of fishes over discrete habitat types is a prerequisite for effective use of EFH in the management of important commercial and recreational fish species. Resolution of the influence of habitat type and environmental factors on the distribution of fishes is confounded by limitations of traditional sampling gears. To date, hydroacoustic technology has been widely accepted as a tool for surveying fishery resources; however few studies have implemented acoustics in ultra shallow (<2 m) coastal waters. Efforts should be made to utilize hydroacoustics for quantifying changes in fish distributions within estuarine environments given the benefits provided through acoustic technology (e.g. ease of deployment, reduced sampling effort, and non-invasive sampling attributes). A technique was developed for acoustically sensing fishes in the shallow, turbid waters of Barataria Bay, Louisiana. A robust and lightweight remotely-controlled transducer platform was designed for deploying acoustic gear. Sources of scattering within the bay were identified through a series of exclosure net experiments designed to quantify potential effects of plankton and suspended solids on acoustic scattering. Analysis filters were developed to reduce the effects of bubble-induced noise, often observed during periods when wind speeds were greater than 4.5 m s-1. Side-aspect acoustic target strength-length and target …

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Thermo And Kinetic Studies On The Sorption And Desorption Of Hydrophobic Organic Contaminants In Sediments, Yunzhou Chai Jan 2005

Thermo And Kinetic Studies On The Sorption And Desorption Of Hydrophobic Organic Contaminants In Sediments, Yunzhou Chai

LSU Doctoral Dissertations

This study investigated the correlation of desorption resistance of hydrophobic organic contaminants (HOCs) in sediment and the heterogeneity of sediment organic matter (SOM). The amorphous and condensed phase organic carbon contents were defined by the method of Gustafsson et al. (1997) using thermal oxidation of sediment under 375°C. The desorption-resistant fraction of contaminants in sediments was operationally defined as the fraction that could not be removed by the adsorbent XAD-2. The correlation of the desorption-resistant fraction with sediment organic carbon characteristics was evaluated for both laboratory-inoculated and field-contaminated sediments. No strong correlation between the desorption resistant fraction in laboratory-inoculated sediments …

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Structural Integrity And Fatigue Crack Propagation Life Assessment Of Welded And Weld-Repaired Structures, Mohammad Shah Alam Jan 2005

Structural Integrity And Fatigue Crack Propagation Life Assessment Of Welded And Weld-Repaired Structures, Mohammad Shah Alam

LSU Doctoral Dissertations

Structural integrity is the science and technology of the margin between safety and disaster. Proper evaluation of the structural integrity and fatigue life of any structure (aircraft, ship, railways, bridges, gas and oil transmission pipelines, etc.) is important to ensure the public safety, environmental protection, and economical consideration. Catastrophic failure of any structure can be avoided if structural integrity is assessed and necessary precaution is taken appropriately. Structural integrity includes tasks in many areas, such as structural analysis, failure analysis, nondestructive testing, corrosion, fatigue and creep analysis, metallurgy and materials, fracture mechanics, fatigue life assessment, welding metallurgy, development of repairing …

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Nutrient Interactions, Plant Productivity, Soil Accretion, And Policy Implications Of Wetland Enhancements In Coastal Louisiana, Christopher Brantley Jan 2005

Nutrient Interactions, Plant Productivity, Soil Accretion, And Policy Implications Of Wetland Enhancements In Coastal Louisiana, Christopher Brantley

LSU Doctoral Dissertations

Ecosystem response, stakeholder interactions, and the policy implications to a wetland assimilation project are reported here for the City of Mandeville, St. Tammany Parish, Louisiana. Between September 1998 and October 2004, input of secondarily treated wastewater effluent was found to have a net positive effect on the downstream wetland receiving basin. The major hydrologic inputs to the system are the effluent, precipitation, and back water flooding from Lake Pontchartrain. Nutrient levels were generally low except in the immediate vicinity of the outfall and removal efficiencies of N and P ranged from 44% to 87% and 25% to 93%, respectively. On …

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Mapping The Other Truth In The Shintech Case: Emancipatory Mapping For Environmental Justice In South Louisiana, Charles Allen Flanagan Jan 2005

Mapping The Other Truth In The Shintech Case: Emancipatory Mapping For Environmental Justice In South Louisiana, Charles Allen Flanagan

LSU Doctoral Dissertations

This dissertation presents an alternative mapping approach which challenges the hegemony of abstract space and instrumental reason propagated by the U.S. Environmental Protection Agency (EPA) in its 1998 study of the Louisiana Department of Environmental Quality's (DEQ) permitting process. The "other truth" is presented through application of concepts from critical theory, critical geography, and the works of Henri Lefebvre to a specific environmental justice struggle in St. James Parish, Louisiana. In 1996 Shintech, Inc. proposed building a polyvinyl chloride facility in St. James Parish, Louisiana. The community, concerned about the considerable toxic burden already present in the area, formed a …

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Modeling The Flow Of Non-Newtonian Fluids In Packed Beds At The Pore Scale, Matthew Balhoff Jan 2005

Modeling The Flow Of Non-Newtonian Fluids In Packed Beds At The Pore Scale, Matthew Balhoff

LSU Doctoral Dissertations

Flow and transport in porous media are important in many science and engineering applications such as composite materials, subsurface water contamination, packed-bed reactors, and enhanced oil recovery. The general approach to modeling such processes is at the continuum scale. Semi-empirical expressions, such as Darcy's law, are substituted for velocity in the continuity equation, which is then coupled with a momentum, mass, and energy balance. While a continuum approach is acceptable in some cases, additional modeling is required for certain non-linear flows, such as multi-phase flows, inertial flows, non-Newtonian flows, and reactive flows. Pore-scale modeling is a first-principles approach to modeling …

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Characterization Of A Modified Poly(Propylene Imine) Dendrimer Host System, Amy D. Morara Jan 2005

Characterization Of A Modified Poly(Propylene Imine) Dendrimer Host System, Amy D. Morara

LSU Doctoral Dissertations

The research in this dissertation focuses on the design of a novel redox-responsive host system that has the ability to encapsulate guest molecules. The host at hand is a tri(ethylene oxide), TEO, pyrrole-terminated PPI dendrimer that possesses water-solubility as a result of the presence of the TEO chains on the pyrrole groups and redox-responsive activity from the pyrrole groups after their oligomerization. The pyrrole moieties at the periphery of the dendrimer exhibit the ability to be oligomerized by oxidation chemistry, and this is shown to aid in the retention and egress of guest molecules located within the dendrimer interior. These …

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Population Dynamics Of Clausocalanus Furcatus (Copepoda, Calanoida) In The Northern Gulf Of Mexico, Hongsheng Bi Jan 2005

Population Dynamics Of Clausocalanus Furcatus (Copepoda, Calanoida) In The Northern Gulf Of Mexico, Hongsheng Bi

LSU Doctoral Dissertations

Copepods are important components of marine ecosystems. Understanding copepod population dynamics can help interpret variations in both primary producers and higher trophic levels. Egg production, stage duration, and stage-specific mortality rates are key parameters describing copepod population dynamics. Estimation of stage-specific mortality is complicated due to a complex life history, patchiness, and sampling biases. This study was undertaken to quantify the population dynamics of the copepod Clausocalanus furcatus in the northern Gulf of Mexico and to assess the utility of available mortality estimation methods in a highly advective environment. Zooplankton samples were taken every 12h from March 18-April 6, and …

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Error Estimates For Stabilized Approximation Methods For Semigroups, Sarah Campbell Mcallister Jan 2005

Error Estimates For Stabilized Approximation Methods For Semigroups, Sarah Campbell Mcallister

LSU Doctoral Dissertations

In this work we analyze error estimates for rational approximation methods, and their stabilizations, for strongly continuous semigroups. Chapter 1 consists of a brief survey of time discretization methods for semigroups. In Chapter 2, we demonstrate a new method for obtaining convergent approximations in the absence of stability for strongly continuous semigroups with arbitrary initial data. In Section 2.2, we state the stabilization result in more general form and show that this method can be used to improve known error estimates by a magnitude of up to one half for smooth initial data. In Section 2.3, we give concrete examples …

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Verbal And Nonverbal Immediacy: Sex Differences And International Teaching Assistants, Tiwa Saechou Jan 2005

Verbal And Nonverbal Immediacy: Sex Differences And International Teaching Assistants, Tiwa Saechou

LSU Doctoral Dissertations

This dissertation explains theory and research concerning international teaching assistants, intercultural communication, nonverbal and verbal immediacy, cognitive, affective, and behavioral learning, and sex differences. One research question and five hypotheses were tested via MANOVA and correlation tests. Six hundred and seven undergraduate students completed instruments measuring verbal and nonverbal immediacy, and cognitive, affective, and behavioral learning. Results supported the research question and three of the five hypotheses. Specifically, U.S. Teaching Assistants used more nonverbal immediacy than International Teaching Assistants. Students’ attitudes toward International Teaching Assistants correlated with students’ learning. Students’ perceptions of ITAs and USTAs on verbal and nonverbal immediacy …

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Constructing A Math Applications, Curriculum-Based Assessment: An Analysis Of The Relationship Between Apllications [Sic] Problems, Computation Problems And Criterion-Referenced Assessments, James E. Connell, Jr. Jan 2005

Constructing A Math Applications, Curriculum-Based Assessment: An Analysis Of The Relationship Between Apllications [Sic] Problems, Computation Problems And Criterion-Referenced Assessments, James E. Connell, Jr.

LSU Doctoral Dissertations

Curriculum-based measurement (CBM) is a well established tool for formative assessment. CBM has also been used for prediction of state test scores. However, validity coefficients between math-CBM and state tests have been moderate at best (Skiba, Magnusson, Martson, and Erickson, 1986; Martson, 1989; Putnam, 1989). The purpose of the present investigation was to develop and evaluate a set of math assessments designed to measure the type of application and problem-solving objectives required on state tests. The "application" type assessments constructed for this study combined characteristics of CBM, accuracy-based curriculum-based assessment (CBA) and criterion-referenced assessment (CRA). Theses assessments were derived from …

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Computational Model For Elasto-Plastic And Damage Analysis Of Plates And Shells, Pawel Benedykt Woelke Jan 2005

Computational Model For Elasto-Plastic And Damage Analysis Of Plates And Shells, Pawel Benedykt Woelke

LSU Doctoral Dissertations

Shells and plates are very important for various engineering applications. Analysis and design of these structures is therefore continuously of interest to the scientific and engineering community. Accurate and conservative assessments of the maximum load carried by the structure, as well as the equilibrium path in both elastic and inelastic range are of paramount importance. Elastic behaviour of shells has been very closely investigated, mostly by means of the finite element method. Inelastic analysis on the other hand, especially accounting for damage effects, has received much less attention from the researchers. A computational model for finite element, elasto-plastic and damage …

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Carbonate Records Of Submarine Hydrocarbon Venting: Northern Gulf Of Mexico, Matthew S. Hackworth Jan 2005

Carbonate Records Of Submarine Hydrocarbon Venting: Northern Gulf Of Mexico, Matthew S. Hackworth

LSU Doctoral Dissertations

Hydrocarbon seep sediments are examined from 3 sites in the Gulf of Mexico (Green Canyon Lease Blocks 232, 185, and 272) to relate the effects of gas hydrates and hydrocarbons on microbial process, pore fluid chemistry, and the processes of authigenic carbonate formation. Hydrocarbon-fueled microbial reactions result in pore fluids with lowered SO42- (all consumed by –10 cm) and enrichments in H2S, alkalinity, and DIC (up to 20 mmol, 30 meq/L, and 18 mmol/L, respectively) which promote carbonate formation. Pore fluid d13CDIC (PDB) is influenced by thermogenic hydrocarbons and crude oil in GC …

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Complexifying The Poetic: Toward A Poiesis Of Curriculum, Donna Lynn Trueit Jan 2005

Complexifying The Poetic: Toward A Poiesis Of Curriculum, Donna Lynn Trueit

LSU Doctoral Dissertations

Inspired by philosopher Richard Rorty’s assertion that we need poetic imagination to move beyond modernity, this pragmatist inquiry seeks to understand the poetic, not as it is rationally defined, but rather as a historically situated discursive practice. In western cultures modernist discursive practices are characterized by rationalist reasoning. Traced to Aristotelian re- interpretations of mimesis (this is that), which structure modernist forms of representation, mimesis operates on a principle of equivalency between the specific and the universal, based on Euclidean, geometric reasoning. Likewise, mimesis underlies poetic representation as an imaginative expression of an objective reality, ideally, a form that moves …

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Effects Of Strong Surface Energy Anisotropy On Stationary And Migrating Grain-Boundary Grooves, Donghong Min Jan 2005

Effects Of Strong Surface Energy Anisotropy On Stationary And Migrating Grain-Boundary Grooves, Donghong Min

LSU Doctoral Dissertations

Grain-boundary migration controls grain growth and is important in materials processing and synthesis. When a grain boundary ends at a free surface, a groove will develop at the tip to reduce the combined surface and grain-boundary energies. This groove may hinder the grain boundary movement and its effect needs to be understood. Previous studies have solved the groove profile for stationary or migrating grain boundaries by assuming small groove slopes with isotropic surface free energy. This work extends the analysis to finite slopes with isotropic or anisotropic surface free energy.
We first study migrating grain-boundary grooves with isotropic surface energy …

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A Conductor's Analysis Of Amaral Vieira's Stabat Mater, Op.240: An Approach Between Music And Rhetoric, Vladimir A. Pereira Silva Jan 2005

A Conductor's Analysis Of Amaral Vieira's Stabat Mater, Op.240: An Approach Between Music And Rhetoric, Vladimir A. Pereira Silva

LSU Doctoral Dissertations

Choral music is one of the most common musical activities in Brazil. However, the lack of biographical studies, music publication, and theoretical works which discuss stylistic and interpretative aspects of choral performance creates problems for conductors. The primary goal of this study is to consider Amaral Vieira’s Stabat Mater, op. 240 specifically from a conductor’s point of view, focusing on biographical, analytical, stylistic, and interpretative issues. The document is divided into three chapters; chapter one discusses twentieth-century Brazilian choral music, Amaral Vieira’s life and music, history and overview of the Stabat Mater, op. 240, and textual aspects. Chapter two presents …

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Economic Valuation Of Natural Resource Management: A Case Study Of The Benuaq Dayak Tribe In Kalimantan, Indonesia, Indah D. Kusuma Jan 2005

Economic Valuation Of Natural Resource Management: A Case Study Of The Benuaq Dayak Tribe In Kalimantan, Indonesia, Indah D. Kusuma

LSU Doctoral Dissertations

The unavailability of total economic values of indigenous people in Indonesia, both in the short and long term, has created the rejection of their existences in the forest area. The purpose of this study is to estimate the total economic value of sustainable forest management conducted by indigenous tribes in Indonesia using total economic value concepts. The tribe’s total economic value is expressed by estimating the use value, indirect use value and non-use value. The study used benefit transfer and survey methods using questionnaires to estimate the tribe’s total economic value. The estimated total economic value of the Benuaq Dayak …

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Using The Biodatamation Strategy To Learn Introductory College Biology: Value-Added Effects On Selected Students' Conceptual Understanding And Conceptual Integration Of The Processes Of Photosynthesis And Celluar Respiration, Jewel Jurovich Reuter Jan 2005

Using The Biodatamation Strategy To Learn Introductory College Biology: Value-Added Effects On Selected Students' Conceptual Understanding And Conceptual Integration Of The Processes Of Photosynthesis And Celluar Respiration, Jewel Jurovich Reuter

LSU Doctoral Dissertations

The purpose of this exploratory research was to study how students learn photosynthesis and cellular respiration and to determine the value added to the student's learning by each of the three technology-scaffolded learning strategy components (animated concept presentations and WebQuest-style activities, data collection, and student-constructed animations) of the BioDatamation™ (BDM) Program. BDM learning strategies utilized the Theory of Interacting Visual Fields™ (TIVF) (Reuter & Wandersee, 2002a, 2002b; 2003a, 2003b) which holds that meaningful knowledge is hierarchically constructed using the past, present, and future visual fields, with visual metacognitive components that are derived from the principles of Visual Behavior (Jones,1995), Human …

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Quasicontinuous Derivatives And Viscosity Functions, Rodica Cazacu Jan 2005

Quasicontinuous Derivatives And Viscosity Functions, Rodica Cazacu

LSU Doctoral Dissertations

In this work we demonstrate how the continuous domain theory can be applied to the theory of nonlinear optimization, particularly to the theory of viscosity solutions. We consider finding the viscosity solution for the Hamilton-Jacobi equation H(x, y) = g(x), with continuous hamiltonian, but with possibly discontinuous right-hand side. We begin by finding a new function space Q(X,L), the space of equivalence classes of quasicontinuous functions from a locally compact set X to a bicontinuous lattice L and we will define on Q(X,L) the qo-topology, which is a variant of classical order topology defined on complete lattices. On this …

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Analytical Separations Using Polymetric Surfactants, Mary Waithira Kamande Jan 2005

Analytical Separations Using Polymetric Surfactants, Mary Waithira Kamande

LSU Doctoral Dissertations

The goal of the research presented in this dissertation is to develop effective analytical methods for the separation of both achiral and chiral analytes using polymeric surfactants. Three analytical techniques are employed to accomplish this objective: open-tubular capillary electrochromatography (OT-CEC), open-tubular capillary electrochromatography coupled to mass spectrometry (OT-CEC/MS), and micellar affinity gradient focusing (MAGF). This research work presents novel application of polymeric surfactants that contributes to improved separations of difficult to separate analytes. The first part focuses on the application of an achiral polyelectrolyte multilayer (PEM) coating using OT-CEC. The PEM coating consisting of the cationic polymer poly (diallyldimethylammonium chloride), …

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Toward A Construct Validation Of The Louisiana School Analysis Model Instructional Staff Questionnaire, Nikki Bray Clark Jan 2005

Toward A Construct Validation Of The Louisiana School Analysis Model Instructional Staff Questionnaire, Nikki Bray Clark

LSU Doctoral Dissertations

This study assessed the construct validity of the School Analysis Model (SAM) Instructional Staff Questionnaire. Construct validation was necessary for several reasons. First, it has not been possible to obtain evidence of the latent factor structure of this key component of the School Analysis Model (SAM). A factor analysis using data collected with the questionnaire was conducted to assess and identify the underlying factor structure of the instrument. Second, there is no evidence that the constructs measured by the SAM are associated with attributes of school performance further empirical analysis was done to determine if latent constructs contained within the …

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The Establishment, Expansion And Ecosystem Effects Of Phragmites Australis, An Invasive Species In Coastal Louisiana, Lee Ellis Stanton Jan 2005

The Establishment, Expansion And Ecosystem Effects Of Phragmites Australis, An Invasive Species In Coastal Louisiana, Lee Ellis Stanton

LSU Doctoral Dissertations

As biological invasions have become a common phenomenon throughout the world, ecologists have intensified efforts to understand why natural communities are susceptible to invasion. Invading species can cause shifts in community structure that result in irreversible changes to ecosystem function. Phragmites australis has rapidly spread in North American coastal wetlands during the past 50 years and has become a dominant feature in Northern Gulf of Mexico brackish marshes. The rate at which Phragmites is spreading or the mechanisms controlling its establishment in these marshes is unknown. My research objectives were to: (1) determine the spatial and temporal patterns of Phragmites …

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An Evaluation Of The Enantiomeric Recognition Of Amino Acid Based Polymeric Surfactants And Cyclodextrins Using Spectroscopic And Chromatographic Methods, Bertha Cedillo Valle Jan 2005

An Evaluation Of The Enantiomeric Recognition Of Amino Acid Based Polymeric Surfactants And Cyclodextrins Using Spectroscopic And Chromatographic Methods, Bertha Cedillo Valle

LSU Doctoral Dissertations

The scope of this dissertation is to explore the enantiomeric recognition properties of amino acid based polymeric surfactants using a combination of analytical techniques including chromatographic and spectroscopic methods. Chapter 1 includes an introduction to chirality and chiral separations using capillary electrophoresis. Using cyclodextrin modified micellar electrokinetic chromatography (CD-MEKC), the enantioseparation of three binaphthyl derivatives using native alpha- and beta-cyclodextrins in combination with various diastereomers of chiral polymeric surfactants (PS) was examined. A reversal of enantiomeric order was observed with the enantiomers of (1,1 S-binaphthyl-2,2 S-diamine (BNA) and (1,1 S-binaphthol (BOH) due to a competition between the two chiral selectors …

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Hydrophobic Guar Gum Derivatives Prepared By Controlled Grafting Processes For Hydraulic Facturing Applications, Ahmad Bahamdan Jan 2005

Hydrophobic Guar Gum Derivatives Prepared By Controlled Grafting Processes For Hydraulic Facturing Applications, Ahmad Bahamdan

LSU Doctoral Dissertations

The synthesis of new water soluble guar gum derivatives is described. Introduction of polyalkoxyalkyleneamide grafts to guar gum or hydroxyopropyl guar was achieved in a three step process: carboxymethylation with sodium chloroacetate, esterification with dimethyl sulfate and amidation with a series of polyalkoxyalkylene-amines. The process steps were followed using infrared spectroscopy; the grafted guar derivatives were characterized using FT-IR and 1H NMR. A series of hydroxypropyl guar derivatives with degrees of carboxymethylations ranging from 0.15-0.25 were modified with polyalkoxyalkyleneamines with molecular weights ranging from 300-3000. The ratio of oxypropylene to oxoethylene units in the polyalkoxyalkyleneamines was varied from 9/1 …

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