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LSU Doctoral Dissertations

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Interference Suppression And Parameter Estimation In Wireless Communication Systems Over Time-Varing Multipath Fading Channels, Jianqiang He Jan 2005

Interference Suppression And Parameter Estimation In Wireless Communication Systems Over Time-Varing Multipath Fading Channels, Jianqiang He

LSU Doctoral Dissertations

This dissertation focuses on providing solutions to two of the most important problems in wireless communication systems design, namely, 1) the interference suppression, and 2) the channel parameter estimation in wireless communication systems over time-varying multipath fading channels. We first study the interference suppression problem in various communication systems under a unified multirate transmultiplexer model. A state-space approach that achieves the optimal realizable equalization (suppression of inter-symbol interference) is proposed, where the Kalman filter is applied to obtain the minimum mean squared error estimate of the transmitted symbols. The properties of the optimal realizable equalizer are analyzed. Its relations with …

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Multiscale Strain Analysis, Timothy Donald Breitzman Jan 2005

Multiscale Strain Analysis, Timothy Donald Breitzman

LSU Doctoral Dissertations

The mathematical homogenization and corrector theory relevant to prestressed heterogeneous materials in the linear-elastic regime is discussed. A suitable corrector theory is derived to reconstruct the local strain field inside the composite. Based on this theory, we develop an inexpensive numerical method for multi scale strain analysis within a prestressed heterogeneous material. The theory also provides a characterization of the macroscopic strength domain. The strength domain places constraints on the homogenized strain field which guarantee that the actual strain in the heterogeneous material lies inside the strength domain of each material participating in the structure.

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An Empirical Study Of Imputation Techniques For Software Data Sets, Sumanth Yenduri Jan 2005

An Empirical Study Of Imputation Techniques For Software Data Sets, Sumanth Yenduri

LSU Doctoral Dissertations

Software Project Effort/Cost/Time Estimation has been one of the hot topics of research in the current software engineering industry. Solutions for effort/cost/time estimation are in great demand. Knowledge of accurate effort/cost/time estimates early in the software project life cycle enables project managers manage and exploit resources efficiently. The constraints of cost and time can also be met. To this day, most companies rely on their historical database of past project data sets to predict estimates for future projects. Like other data sets, software project data sets also suffer from numerous problems. The most important problem is they contain missing/incomplete data. …

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Comparative Studies Of Sperm Cryopreservation Of Diploid And Tetraploid Pacific Oysters, Qiaoxiang Dong Jan 2005

Comparative Studies Of Sperm Cryopreservation Of Diploid And Tetraploid Pacific Oysters, Qiaoxiang Dong

LSU Doctoral Dissertations

This dissertation addressed comparative studies of sperm cryopreservation of diploid and tetraploid Pacific oysters, Crassostrea gigas, with an emphasis on the development of standardized and optimized protocols. This includes comparative ultrastructural differences between sperm from diploid and tetraploid oysters, methods for the rapid estimation of sperm concentration, optimization of cryopreservation, and evaluation of the mechanisms for sperm agglutination (formation of clumps or elongated "noodles") in thawed samples. Currently, cryopreserved sperm has not been commercialized in any aquatic species, and standardization and optimization could greatly benefit the potential commercialization of its use. In oysters specifically, cryopreserved sperm from tetraploids would facilitate …

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Synthetic Development And Application Of Compounds With Biological Relevance, Jeffery Caleb Clark Jan 2005

Synthetic Development And Application Of Compounds With Biological Relevance, Jeffery Caleb Clark

LSU Doctoral Dissertations

Nature has provided a vast number of compounds that have medicinal application. The use of these compounds provided by nature however, is limited by the amount of a specific compound that nature provides. The synthesis of these molecules and their derivatives provides an even greater number of compounds for biological screening. Various pyrroles, the heterocyclic building blocks of porphyrins, can be prepared synthetically over several steps. The implementation of carboranes on pyrrole rings intrinsically provides substrates that can be converted into porphyrins bearing carborane substituents. The condensation of these carboranylpyrroles with carboranylaldehydes provides carboranylporphyrins bearing a higher order of carborane …

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Boundary Effects On Non-Equilibrium Localized Structures In Spatially Extended Systems, Aniruddha Yadav Jan 2005

Boundary Effects On Non-Equilibrium Localized Structures In Spatially Extended Systems, Aniruddha Yadav

LSU Doctoral Dissertations

A study of the effects of system boundaries on bistable front propagation in nonequilibrium reaction-diffusion systems is presented. Two model partial differential equations displaying bistable fronts, with distinct experimental motivations and mathematical structure, are examined in detail utilizing simulations and perturbation techniques. We see that propagating fronts in both models bounce, trap, pin, or oscillate at the boundary, contingent on the imposed boundary condition, initial front speed and distance from the boundary. The similarities in front boundary interactions in these two models is traced to the fact that they display the same front instability (Ising-Bloch bifurcation) that controls the speed …

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A Case Study Inquiry Into The Relative Impact Of Balanced Reading Instruction On Hispanic Students In A Highly Culturally Diverse Elementary School, Rita Ramirez Jan 2005

A Case Study Inquiry Into The Relative Impact Of Balanced Reading Instruction On Hispanic Students In A Highly Culturally Diverse Elementary School, Rita Ramirez

LSU Doctoral Dissertations

This research explores the relative impact of Balanced Reading instruction upon Hispanic students in a highly culturally diverse elementary school. This case study inquiry focuses on Hispanic students learning to read in English in kindergarten, first and third grade, how these Hispanic students are affected by the classroom setting within the context of the Balanced Reading instructional framework of each respective grade, and what are the similarities and differences in the learning methodologies and strategies that impact the learning curve of these Hispanic students. The researcher collects qualitative data to determine the methods and strategies found to be most effective …

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Impulsive Systems, Stanislav Zabic Jan 2005

Impulsive Systems, Stanislav Zabic

LSU Doctoral Dissertations

Impulsive systems arise when dynamics produce discontinuous trajectories. Discontinuties occur when movements of states happen over a small interval that resembles a point-mass measure. We adopt the formalism in which the controlled dynamic inclusion is the sum of a slow and a fast time velocities belonging to two distinct vector fields. Fast time velocities are controlled by a vector valued Borel measure. The trajectory of impulsive systems is a function of bounded variation. To give a definition of solutions, a notion of graph completion of the control measure is needed. In the nonimpulsive case, a solution can be defined as …

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Aspects Of The Life History, Ecophysiology, Bioenergetics, And Population Dynamics Of The Cownose Ray, Rhinoptera Bonasus, In The Northern Gulf Of Mexico, Julie Ann Neer Jan 2005

Aspects Of The Life History, Ecophysiology, Bioenergetics, And Population Dynamics Of The Cownose Ray, Rhinoptera Bonasus, In The Northern Gulf Of Mexico, Julie Ann Neer

LSU Doctoral Dissertations

The cownose ray, Rhinoptera bonasus, is an elasmobranch commonly observed throughout the Gulf of Mexico. Cownose rays appear to be sensitive to water temperature. I performed laboratory experiments and collected field data to obtain basic life history information, and used the information to configure an individual-based bioenergetics model. The bioenergetics model was coupled to a matrix projection model, and the coupled models were used to predict how warmer and cooler water temperatures, compared to current conditions, would affect the growth and population dynamics of the cownose rays. The life history study determined weight at age, maturity by weight, and fecundity …

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Temporal And Spatial Harvest Patterns Of River Otter In Louisiana And Its Potential Use As A Bioindicator Species Of Water Quality, Daniel Gustavo Scognamillo Jan 2005

Temporal And Spatial Harvest Patterns Of River Otter In Louisiana And Its Potential Use As A Bioindicator Species Of Water Quality, Daniel Gustavo Scognamillo

LSU Doctoral Dissertations

Louisiana is the leading state in number of river otters used in reintroduction programs in other states and in the production of pelts. However, habitat loss and degradation have prompted concern about the status of otter populations. This dissertation undertakes a spatial and temporal analysis of river otter harvest activity and examines environmental factors related to monitoring mercury levels in streams in Louisiana. Harvest data for 1957-2004 were analyzed to identify spatial and temporal trends in otter harvest activity. Changes have occurred in the last 20 years in the spatial dynamics of otter harvest in Louisiana, these include an increasing …

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Belowground Productivity Of Mangrove Forests In Southwest Florida, Beatriz Eugenia Giraldo Sánchez Jan 2005

Belowground Productivity Of Mangrove Forests In Southwest Florida, Beatriz Eugenia Giraldo Sánchez

LSU Doctoral Dissertations

Studies in belowground dynamics are limited mainly due to the difficulty of studying roots despite wide recognition of its importance. This dissertation focused on methods for analyzing mangrove roots, root responses to phosphorus and flooding, and variation in root production between forest types. Techniques to separate live and dead roots such as colorimetric, fluorescence, buoyancy, and visual assessment were compared. The traditional method of visual assessment combined with root buoyancy was accurate, fast, and applicable to larger samples. Additionally, techniques such as rhizotrons, root ingrowth cores, and root image analysis were useful to study mangrove roots. Root and litter production, …

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Common Sense Philosophy And Politics In America: John Witherspoon, James Mccosh, And William James, Scott Philip Segrest Jan 2005

Common Sense Philosophy And Politics In America: John Witherspoon, James Mccosh, And William James, Scott Philip Segrest

LSU Doctoral Dissertations

This dissertation examines the political significance of the two leading strains of common sense thought in the history of American philosophy—Scottish Common Sense and Pragmatism—as suggested in the writings of John Witherspoon and James McCosh in the Scottish Common Sense line, and of the more famous co-founder of Pragmatism, William James. These two strains of American common sense are placed in context of the larger Western common sense tradition. Each is shown to aim at finding a solid middle ground epistemologically between skeptical doubt and idealistic certitude that could serve as a stable basis for moral and political life. Witherspoon, …

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Improvements In Groundwater Flow Modeling Through The Integration Of Resistivity Logs And Hydraulic Conductivity And The Use Of Variogram Uncertainty, Asheka Rahman Jan 2005

Improvements In Groundwater Flow Modeling Through The Integration Of Resistivity Logs And Hydraulic Conductivity And The Use Of Variogram Uncertainty, Asheka Rahman

LSU Doctoral Dissertations

This study developed a coregionalized model to estimate hydraulic conductivity using spatial cross correlation between hydraulic conductivity and borehole geophysical data (a transform of the formation factor). An experimental pseudocross variogram is used instead of a cross variogram because data are not collocated. Experimental variogram uncertainty is investigated using confidence intervals for the experimental variogram calculated assuming variogram sills are lognormally distributed. These intervals are used for sensitivity modeling using kriging, cokriging, simulation and cosimulation. The hydraulic conductivity fields generated by kriging, cokriging, simulation, and cosimulation are then used in a high-resolution groundwater model created using telescopic mesh refinement (TMR) …

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Zeta Functions Of Finite Graphs, Debra Czarneski Jan 2005

Zeta Functions Of Finite Graphs, Debra Czarneski

LSU Doctoral Dissertations

Ihara introduced the zeta function of a finite graph in 1966 in the context of p-adic matrix groups. The idea was generalized to all finite graphs in 1989 by Hashimoto. We will introduce the zeta function from both perspectives and show the equivalence of both forms. We will discuss several properties of finite graphs that are determined by the zeta function and show by counterexample several properties of finite graphs that are not determined by the zeta function. We will also discuss the relationship between the zeta function of a finite graph and the spectrum of a finite graph.

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Laguerre Functions Associated To Euclidean Jordan Algebras, Michael Aristidou Jan 2005

Laguerre Functions Associated To Euclidean Jordan Algebras, Michael Aristidou

LSU Doctoral Dissertations

Certain differential recursion relations for the Laguerre functions, defined on a symmetric cone Ω, can be derived from the representations of a specific Lie algebra on L2(Ω,dμv). This Lie algebra is the corresponding Lie algebra of the Lie group G that acts on the tube domain T(Ω)=Ω+iV, where V is the associated Euclidean Jordan algebra of Ω. The representations involved are the highest weight representations of G on L2(Ω,dμv). To obtain these representations, we start from the highest weight representations of G on Hv(T(Ω)), the Hilbert space of holomorphic functions …

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Dissipative Lipschitz Dynamics, Vinicio Rafael Rios Jan 2005

Dissipative Lipschitz Dynamics, Vinicio Rafael Rios

LSU Doctoral Dissertations

In this dissertation we study two related important issues in control theory: invariance of dynamical systems and Hamilton-Jacobi theory associated with optimal control theory. Given a control system modelled as a differential inclusion, we provide necessary and sufficient conditions for the strong invariance property of the system when the dynamic satisfies a dissipative Lipschitz condition. We show that when the dynamic is almost upper semicontinuous and satisfies the dissipative Lipschitz property, these conditions can be expressed in terms of approximate Hamilton-Jacobi inequalities, which subsumes the classic infinitesimal characterization of strongly invariant systems given under the Lipschitz assumtion. In the important …

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Efficient Automatic Correction And Segmentation Based 3d Visualization Of Magnetic Resonance Images, Mikhail V. Milchenko Jan 2005

Efficient Automatic Correction And Segmentation Based 3d Visualization Of Magnetic Resonance Images, Mikhail V. Milchenko

LSU Doctoral Dissertations

In the recent years, the demand for automated processing techniques for digital medical image volumes has increased substantially. Existing algorithms, however, still often require manual interaction, and newly developed automated techniques are often intended for a narrow segment of processing needs. The goal of this research was to develop algorithms suitable for fast and effective correction and advanced visualization of digital MR image volumes with minimal human operator interaction. This research has resulted in a number of techniques for automated processing of MR image volumes, including a novel MR inhomogeneity correction algorithm derivative surface fitting (dsf), automatic tissue detection algorithm …

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Long Term Pressure Behavior In Turbidite Reservoirs, Feng Wang Jan 2005

Long Term Pressure Behavior In Turbidite Reservoirs, Feng Wang

LSU Doctoral Dissertations

In this study, we investigated several possible mechanisms that would give rise to the anomalous pressure behavior (early concave-up on Horner plot or upward drift on the derivative curve of the log-log plot and asymmetry between the pressure drawdown and buildup behavior) sometimes encountered in the turbidite reservoirs in GOM primarily using numerical simulation and 2-level experimental designs. We ascertained the most influential parameters to the pressure behavior and identified that multilayer commingled system and the leaky compartment model are the most probable mechanisms to cause the anomalous behavior due to layer or zone property contrast to a certain degree. …

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Ability Of College Students To Simulate Adhd On Objective Measure Of Attention, Randee Lee Booksh Jan 2005

Ability Of College Students To Simulate Adhd On Objective Measure Of Attention, Randee Lee Booksh

LSU Doctoral Dissertations

Complaints of ADHD symptoms in college students are not uncommon and college students frequently self-refer for assessment of ADHD. Some may seek out a diagnosis to obtain academic accommodations and/or stimulant medication. Diagnosing ADHD in college students is largely reliant on self-report measures, and to a lesser extent, objective measures of attention. The typical college student has easy access to information about ADHD, potentially facilitating efforts to simulate self-reported symptoms. The present study examined the ability of college students to effectively simulate ADHD on objective and self-report measures of attention, and examined the relationship between knowledge of ADHD and ability …

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Parallel Molecular Dynamics Simulations Of Pressure-Induced Structural Transformations In Cadmium Selenide Nanocrystals, Nicholas Jabari Ouma Lee Jan 2005

Parallel Molecular Dynamics Simulations Of Pressure-Induced Structural Transformations In Cadmium Selenide Nanocrystals, Nicholas Jabari Ouma Lee

LSU Doctoral Dissertations

Parallel molecular dynamics (MD) simulations are performed to investigate pressure-induced solid-to-solid structural phase transformations in cadmium selenide (CdSe) nanorods. The effects of the size and shape of nanorods on different aspects of structural phase transformations are studied. Simulations are based on interatomic potentials validated extensively by experiments. Simulations range from 105 to 106 atoms. These simulations are enabled by highly scalable algorithms executed on massively parallel Beowulf computing architectures. Pressure-induced structural transformations are studied using a hydrostatic pressure medium simulated by atoms interacting via Lennard-Jones potential. Four single-crystal CdSe nanorods, each 44Å in diameter but varying in length, in the …

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Dynamical Systems With Time Delay, Norma Ortiz Jan 2005

Dynamical Systems With Time Delay, Norma Ortiz

LSU Doctoral Dissertations

In this dissertation, we study necessary conditions and weak invariance properties of dynamical systems with time delay. A number of results have been obtained recently that refine necessary conditions of optimal solutions for nonsmooth dynamical systems without time delay. In this dissertation, we examine the extension of some of these results to problems with time delay. In particular, we study the generalized problem of Bolza with the addition of delay in the state and velocity variables and refer to this problem as the Neutral Problem of Bolza. We consider the relationship between the generalized problem of Bolza with time delay …

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Power And Memory Optimization Techniques In Embedded Systems Design, Atef Khalil Allam Jan 2005

Power And Memory Optimization Techniques In Embedded Systems Design, Atef Khalil Allam

LSU Doctoral Dissertations

Embedded systems incur tight constraints on power consumption and memory (which impacts size) in addition to other constraints such as weight and cost. This dissertation addresses two key factors in embedded system design, namely minimization of power consumption and memory requirement. The first part of this dissertation considers the problem of optimizing power consumption (peak power as well as average power) in high-level synthesis (HLS). The second part deals with memory usage optimization mainly targeting a restricted class of computations expressed as loops accessing large data arrays that arises in scientific computing such as the coupled cluster and configuration interaction …

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The Stereoselective Synthesis Of The Butyrolactone-Bridged [8-5-5] Tricyclic Ring Systems Of (+/-)-Asteriscanolide Via The Titanium-Mediated Hetero-Pauson-Khand Reaction, Mohamed G. Sherriff Jan 2005

The Stereoselective Synthesis Of The Butyrolactone-Bridged [8-5-5] Tricyclic Ring Systems Of (+/-)-Asteriscanolide Via The Titanium-Mediated Hetero-Pauson-Khand Reaction, Mohamed G. Sherriff

LSU Doctoral Dissertations

The stereoselective construction of the tricyclic ring system of asteriscanolide from cyclooctadiene has been achieved. The synthesis involves two main steps; the synthesis of the aldehyde precursor(5)and the titanium-mediated cabocyclization of 5 to make the three rings of 43 stereoselectively.

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Shear Induced Orientation In Polymer-Clay Solutions And Their Influence On The Structure In Multilayered Films, Matthew Michael Malwitz Jan 2005

Shear Induced Orientation In Polymer-Clay Solutions And Their Influence On The Structure In Multilayered Films, Matthew Michael Malwitz

LSU Doctoral Dissertations

The influence of shear on viscoelastic solutions of poly(ethylene oxide) (PEO) and clay (Cloisite, CNA) was investigated by rheology and small angle neutron scattering (SANS) under shear. These measurements determined the shear-induced orientation of the clay and the polymer as well as their relaxation behavior after cessation of shear. Comparison of PEO-CNA solutions (~100 nm diameter platelets) to previously studied PEO-Laponite gels (~30 nm diameter platelets) found that the orientation of CNA platelets occurs at much lower shear rates. Additionally, the relaxation times were much longer for CNA platelets than for Laponite platelets. From these solutions and gels, multilayered nanocomposite …

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Ecotoxicology Of Metal-Hydrocarbon Mixtures In Benthic Invertebrates, Kurt A. Gust Jan 2005

Ecotoxicology Of Metal-Hydrocarbon Mixtures In Benthic Invertebrates, Kurt A. Gust

LSU Doctoral Dissertations

Metal-hydrocarbon mixtures are becoming increasingly prevalent in natural environments due to expanding industrial activity and urbanization. The ecotoxicology of metal-hydrocarbon mixtures in benthic environments is of particular concern because both classes of contaminants partition to sediments and can thereby exert toxic effects in benthic organisms. Mixtures of dissimilar chemicals (including metals and hydrocarbons) are broadly hypothesized to elicit independent toxic effects however; this hypothesis has little supporting data. The purpose of this dissertation was to test this hypothesis for metal-hydrocarbon mixtures using environmentally relevant exposures and to determine mechanisms for observed interactive effects. Sediment and water-only bioassays were conducted employing …

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Broadcast In Sparse Conversion Optical Networks Using Fewest Converters, Tong Yi Jan 2005

Broadcast In Sparse Conversion Optical Networks Using Fewest Converters, Tong Yi

LSU Doctoral Dissertations

Wavelengths and converters are shared by communication requests in optical networks. When a message goes through a node without a converter, the outgoing wavelength must be the same as the incoming one. This constraint can be removed if the node uses a converter. Hence, the usage of converters increases the utilization of wavelengths and allows more communication requests to succeed. Since converters are expensive, we consider sparse conversion networks, where only some specified nodes have converters. Moreover, since the usage of converters induces delays, we should minimize the use of available converters. The Converters Usage Problem (CUP) is to use …

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Dragos Tanasescu's Treaties Of Pianistic Technique, Lucian B. Zidaru Jan 2005

Dragos Tanasescu's Treaties Of Pianistic Technique, Lucian B. Zidaru

LSU Doctoral Dissertations

This study examines Dragos Tanasescu's fingering system and technical exercises presented in Treatise of Pianistic Technique. The Treatise contains four books, each one dedicated to a segment of technical problems. Tanasescu's main contribution to the piano technique is the applications of math permutation formulas to create all possible arrangements of fingering patterns. His treatise continues previous technical approaches of A. Kullak, F. Liszt, J. Pischna and E. Dohnanyi. Earlier methods organize the technical material by one principle: fingerings. The purpose of this study is to illustrate the characteristics of Tanasescu's fingering system presented in Treatise of Pianistic Technique, and provide …

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Biologically Inspired Learning System, Patrick Mcdowell Jan 2005

Biologically Inspired Learning System, Patrick Mcdowell

LSU Doctoral Dissertations

Learning Systems used on robots require either a-priori knowledge in the form of models, rules of thumb or databases or require that robot to physically execute multitudes of trial solutions. The first requirement limits the robot’s ability to operate in unstructured changing environments, and the second limits the robot’s service life and resources. In this research a generalized approach to learning was developed through a series of algorithms that can be used for construction of behaviors that are able to cope with unstructured environments through adaptation of both internal parameters and system structure as a result of a goal based …

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Separation And In Situ Catalytic Testing Of A Dirhodium Tetraphosphine Catalyst, Bobby Lloyd Barker Jan 2005

Separation And In Situ Catalytic Testing Of A Dirhodium Tetraphosphine Catalyst, Bobby Lloyd Barker

LSU Doctoral Dissertations

Attempts to study the asymmetric hydroformylation abilities of [rac-Rh2(nbd)2(et,ph-P4)](BF4)2 were made through the separation of the enantiomers of et,ph-P4 using a chiral HPLC column. Efforts were also made to optimize the NiCl2 separation chemistry for the methyl analogue of et,ph-P4 for use in asymmetric hydroformylation. A study of hydroformylation of olefins using [rac-Rh2(nbd)2(et,ph-P4)](BF4)2 in ionic liquids was also performed, leading directly to the important (and unexpected) effect of increased hydrogen pressure on [rac-Rh2(nbd)2(et,ph-P4)](BF4)2 in the acetone/water system to …

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Long-Term Freshwater Input And Sediment Load From Three Tributaries To Lake Pontchartrain, Louisiana, Kangsheng Wu Jan 2005

Long-Term Freshwater Input And Sediment Load From Three Tributaries To Lake Pontchartrain, Louisiana, Kangsheng Wu

LSU Doctoral Dissertations

Lake Pontchartrain and the drainage basin have experienced environmental degradation because of human settlement, land use and climate changes. A thorough understanding of hydrologic trends and variability associated with the changes is critical for sustainable water resources management and ecosystem restoration in the region. This study examined freshwater inflow (1940-2002) and suspended solids loadings (1978-2001) from three upper Lake Pontchartrain watersheds that contribute to the lake estuary: the Amite, Tickfaw, and Tangipahoa river watersheds. The relationships of freshwater inflow and suspended solids loadings with climate variables and population growth were investigated. Using observed daily discharge, a spatially-distributed hydrologic model (SWAT) …

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