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Full-Text Articles in Physical Sciences and Mathematics

Magnetic, Thermodynamic And Transport Properties Of The Magnetic Semiconductor Fe₁₋Xcoxs₂ And Superconducting Lasb₂, Song Guo Jan 2006

Magnetic, Thermodynamic And Transport Properties Of The Magnetic Semiconductor Fe₁₋Xcoxs₂ And Superconducting Lasb₂, Song Guo

LSU Doctoral Dissertations

In recent years magnetic semiconductors have attracted a great deal of attention because it is thought that they can be used to generate spin polarized current in spintronics, an emerging field where the spin degree of freedom of charge carriers is utilized in microelectronic devices. In this dissertation work, we investigate the magnetic, thermodynamic, and transport properties of the magnetic semiconductor Fe1-XCoxS2 for x less than 0.14, the doping range where Insulator-to-Metal and paramagnetic-to-ferromagnetic transitions occur. We discovered that the Kondo effect is an important ingredient in the paramagnetic region of magnetic semiconductor Fe1-X …


Nutrient Constraints On Plant Community Production And Organic Matter Accumulation Of Subtropical Floating Marshes, Guerry O., Jr. Holm Jr. Jan 2006

Nutrient Constraints On Plant Community Production And Organic Matter Accumulation Of Subtropical Floating Marshes, Guerry O., Jr. Holm Jr.

LSU Doctoral Dissertations

In the cycle of delta growth and decay, peat-forming wetlands span a time and space continuum. Later in the delta cycle, freshwater floating marshes become increasingly removed from external sediment subsidy and internal nutrient cycling controls plant productivity and organic matter accumulation. An interesting question is whether increased external nutrient loading can affect the basic processes that lead to peat formation—plant production and organic matter decomposition. I conducted several field studies to understand whether belowground organic matter accumulation and decomposition were affected with increased nutrient exposure; in addition, the plant community was monitored over three years. A laboratory soil respiration …


Integral Cohomology Of The Siegel Modular Variety Of Degree Two And Level Three, Mustafa Arslan Jan 2006

Integral Cohomology Of The Siegel Modular Variety Of Degree Two And Level Three, Mustafa Arslan

LSU Doctoral Dissertations

In this thesis work Deligne's spectral sequence Ep,qr with integer coefficients for the embedding of the Siegel modular variety of degree two and level three, A2(3) into its Igusa compactification, A2(3)*, is investigated. It is shown that E3 = E and this information is applied to compute the cohomology groups of A2(3) over the integers.


Belowground Biomass Of Spartina Alterniflora: Seasonal Variability And Response To Nutrients, Faith Armand Darby Jan 2006

Belowground Biomass Of Spartina Alterniflora: Seasonal Variability And Response To Nutrients, Faith Armand Darby

LSU Doctoral Dissertations

Spartina alterniflora is a salt marsh macrophyte found from Canada to the Gulf of Mexico which often provides the dominant plant cover. Although S. alterniflora is well known for its high aboveground productivity, fifty to ninety percent of the total plant production occurs belowground. No previous studies address the seasonal variation of belowground biomass or the response of above-and belowground biomass to nutrients at the southern limits of its U. S. range. The objectives of this study were to: 1) document the seasonal variability of its above- and belowground biomass and test for responses to various combinations of N, P, …


A Community Approach To Identifying Essential Fish Habitat Of Spotted Seatrout, Cynoscion Nebulosus, In Barataria Bay, La, Pamela Sharon Dawn Macrae Jan 2006

A Community Approach To Identifying Essential Fish Habitat Of Spotted Seatrout, Cynoscion Nebulosus, In Barataria Bay, La, Pamela Sharon Dawn Macrae

LSU Doctoral Dissertations

Louisiana wetlands are disappearing at a dramatic rate, providing an impetus for identifying essential fish habitat (EFH) in this region. The distribution, relative abundance, biomass, length and food web dynamics of spotted seatrout, Cynoscion nebulosus, as well as the fish assemblage structure were examined in Barataria Bay, LA, in relation to habitat type and physical/chemical properties of the water. All fish were collected from three sites located along a salinity gradient, each contained the three habitat types of interest: marsh edge, soft bottom and oyster shell, and were sampled monthly from May 2003 to May 2004 with gillnets. Habitat preference …


Synthesis, Characterization And Properties Of Cooper(Ii) Beta-Diketonate Macrocycles, Sylvester Burton Jan 2006

Synthesis, Characterization And Properties Of Cooper(Ii) Beta-Diketonate Macrocycles, Sylvester Burton

LSU Doctoral Dissertations

This dissertation deals with the synthesis and properties of multidentate β-diketone ligands and their transition-metal complexes. (1) We prepared two bis(β-diketones), C1BAH2 and p-XBAH2 (see sketch below), determined their crystal structures, and studied their reactions with copper(II). We envisioned that they would form macrocyclic complexes with 3-6 metal atoms. In both cases, although the initial products are soluble, as expected for the desired molecular products, we were unable to isolate well-behaved molecular solids. In the case of C1BAH2, this may be because the cyclic product requires an unusual combination of conformations of …


Representation Properties Of Definite Lattices In Function Fields, Jean Edouard Bureau Jan 2006

Representation Properties Of Definite Lattices In Function Fields, Jean Edouard Bureau

LSU Doctoral Dissertations

This work is made of two different parts. The first contains results concerning isospectral quadratic forms, and the second is about regular quadratic forms. Two quadratic forms are said to be isospectral if they have the same representation numbers. In this work, we consider binary and ternary definite integral quadratic form defined over the polynomial ring F[t], where F is a finite field of odd characteristic. We prove that the class of such a form is determined by its representation numbers. Equivalently, we prove that there is no nonequivalent definite F[t]-lattices of rank 2 or 3 having the same theta …


An Inverse Homogenization Design Method For Stress Control In Composites, Michael Stuebner Jan 2006

An Inverse Homogenization Design Method For Stress Control In Composites, Michael Stuebner

LSU Doctoral Dissertations

This thesis addresses the problem of optimal design of microstructure in composite materials. The work involves new developments in homogenization theory and numerical analysis. A computational design method for grading the microstructure in composite materials for the control of local stress in the vicinity of stress concentrations is developed. The method is based upon new rigorous multiscale stress criteria connecting the macroscopic or homogenized stress to local stress fluctuations at the scale of the microstructure. These methods are applied to three different types of design problems. The first treats the problem of optimal distribution of fibers with circular cross section …


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 …


A Neural Network Model For Classification Of Coastal Wetlands Vegetation Structure With Moderate Resolution Imaging Spectro-Radiometer (Modis) Data, Evaristo Joseph Liwa Jan 2006

A Neural Network Model For Classification Of Coastal Wetlands Vegetation Structure With Moderate Resolution Imaging Spectro-Radiometer (Modis) Data, Evaristo Joseph Liwa

LSU Doctoral Dissertations

Mapping coastal marshes is an important component in the management of coastal environments. Classification of marshes using remote sensing data has traditionally been performed by employing either parametric supervised classification algorithms or unsupervised classification algorithms. The implementation of these conversional classification methods is based on the underlying distributions concerning the probability density functions (PDF). Neural networks provide a practical approach to this classification because they are essentially non-parametric data transformations that are not restricted by any underlying assumptions. The major objective of this study was to evaluate the ability of neural networks using Moderate Resolution Imaging Spectro-radiometer (MODIS) data to …


Some Factors Affecting The Interfacial Interaction At Thermomechanical Pulp Fiber And Polypropylene Interphase, Sangyeob Lee Jan 2006

Some Factors Affecting The Interfacial Interaction At Thermomechanical Pulp Fiber And Polypropylene Interphase, Sangyeob Lee

LSU Doctoral Dissertations

This dissertation focused on some selected factors that influence the interfacial interactions at the interphase between wood based materials and thermoplastic surfaces. Several treatments were applied to enhance interfacial properties. In general, interfacial properties were altered by physical and chemical surface modification. Study of the interfacial interactions between wood fiber surfaces as a reinforced material and thermoplastics as a matrix material is important to understand fundamentals of wood fiber-plastic composites (WPC). This study represents fundamental research to define treatment effects on surfaces of wood pulp fibers and polypropylene (PP) film. Two thermosets, ion implantations, and maleic anhydride (MA) grafting were …


Applications Of Titanium-Mediated Reductive Coupling And Cyclocarbonylation Reactions Toward Natural Product Synthesis, Maria A. Appeaning Jan 2006

Applications Of Titanium-Mediated Reductive Coupling And Cyclocarbonylation Reactions Toward Natural Product Synthesis, Maria A. Appeaning

LSU Doctoral Dissertations

Previous work in our laboratory has demonstrated not only a synthetic value of tandem reductive cyclization - carbonylation reactions in the preparation of complex molecules but also the interesting stereoselectivity observed therein. The first part of this work employs the titanium-mediated cyclocarbonylation of tethered dienals for the synthesis of prostaglandin analogues, in particular PGF and methyl jasmonate. Based on this hetero Pauson-Khand strategy, we have established an efficient racemic route to both the prostaglandin and the methyl jasmonate core skeletons. Moderate to excellent selectivities with regard to the hetero Pauson-Khand reaction were observed in both cases. The second part …


Population Boundaries And Gravitational-Wave Templates For Evolving White Dwarf Binaries, Ravi Kumar Kopparapu Jan 2006

Population Boundaries And Gravitational-Wave Templates For Evolving White Dwarf Binaries, Ravi Kumar Kopparapu

LSU Doctoral Dissertations

We present results from our analysis of double white dwarf (DWD) binary star systems in the inspiraling and mass-transfer stages of their evolution. Theoretical constraints on the properties of the white dwarf stars allow us to map out the DWD trajectories in the gravitational-wave amplitude-frequency domain and to identify population boundaries that define distinct sub-domains where inspiraling and/or mass-transferring systems will and will not be found. We identify for what subset of these populations it should be possible to measure frequency changes and, hence, directly follow orbit evolutions given the anticipated operational time of the proposed space-based gravitational-wave detector, LISA. …


River, Tidal And Wind Interactions In A Deltaic Estuarine System, Gregg Snedden Jan 2006

River, Tidal And Wind Interactions In A Deltaic Estuarine System, Gregg Snedden

LSU Doctoral Dissertations

The balance between river and marine influences is important in governing landscape sustainability in river deltas. River- and atmospherically driven sea level variability, sediment loading, and estuary-ocean exchange in the Mississippi River delta are examined in this study. Subtidal estuarine sea level variability in the Breton Sound estuary was driven by a combination of remote atmospheric forcing outside the estuary over the continental shelf and controlled river inputs through a gated diversion structure at the estuary head. The highly-frictional deltaic landscape acted as a low-pass filter to coastal fluctuations near the estuary mouth. When substantial quantities river water were discharged …


Effective Bootstrapping Of Peer-To Peer Networks Over Mobile Ad-Hoc Networks, Wei Ding Jan 2006

Effective Bootstrapping Of Peer-To Peer Networks Over Mobile Ad-Hoc Networks, Wei Ding

LSU Doctoral Dissertations

Mobile Ad-hoc Networks (MANETs) and Peer-to-Peer (P2P) networks are vigorous, revolutionary communication technologies in the 21st century. They lead the trend of decentralization. Decentralization will ultimately win clients over client/server model, because it gives ordinary network users more control, and stimulates their active participation. It is a determinant factor in shaping the future of networking. MANETs and P2P networks are very similar in nature. Both are dynamic, distributed. Both use multi-hop broadcast or multicast as major pattern of traffic. Both set up connection by self-organizing and maintain connection by self-healing. Embodying the slogan "networking without networks," both abandoned traditional client/server …


Structural And Forecasting Softwood Lumber Models With A Time Series Approach, Nianfu Song Jan 2006

Structural And Forecasting Softwood Lumber Models With A Time Series Approach, Nianfu Song

LSU Doctoral Dissertations

The development of cointegration theories and the presence of nonstationarity in time series raised serious concerns about possible spurious estimations in forest products models. Based on the results of Hsiao (1997a, 1997b), all the virtues of two-stage least square (2SLS) hold if there are sufficient cointegration relations. Stationary null and nonstationary null unit root tests and monthly seasonal unit root tests were applied to the time series used in this dissertation. Cointegration tests with exogenous variables were performed to justify the 2SLS. A regional error correction model (ECM) with four regional lumber supply and demand equations and a U.S.-Canada supply …


A Computational Framework For The Structural Change Analysis Of 3d Volumes Of Microscopic Specimens, Madhusudhanan Balasubramanian Jan 2006

A Computational Framework For The Structural Change Analysis Of 3d Volumes Of Microscopic Specimens, Madhusudhanan Balasubramanian

LSU Doctoral Dissertations

Glaucoma, commonly observed with an elevation in the intraocular pressure level (IOP), is one of the leading causes of blindness. The lamina cribrosa is a mesh-like structure that provides axonal support for the optic nerves leaving the eye. The changes in the laminar structure under IOP elevations may result in the deaths of retinal ganglion cells, leading to vision degradation and loss. We have developed a comprehensive computational framework that can assist the study of structural changes in microscopic structures such as lamina cribrosa. The optical sectioning property of a confocal microscope facilitates imaging thick microscopic specimen at various depths …


Two-Dimensional And High-Throughput Electrophoretic Separation Of Proteins Using Polymeric Microchips, Hamed Shadpour Jan 2006

Two-Dimensional And High-Throughput Electrophoretic Separation Of Proteins Using Polymeric Microchips, Hamed Shadpour

LSU Doctoral Dissertations

A major task in proteomics is to identify proteins from a biological sample using two-dimensional (2-D) separation prior to mass spectrometry of peptides generated via proteolytic digestion of the proteins. For 2-D separations, microfluidic devices are superior to bench top and capillary-based systems since they potentially provide higher separation efficiencies due to the minimal dead volumes produced during peak transfer between the two separation dimensions. In addition, fast separations can be envisioned because the column lengths are typically shorter in microfluidic platforms without scarifying peak capacity. High-throughput capabilities are extremely desirable for many types of bio-analytical analyses, such as understanding …


Filippov's Operator And Discontinuous Differential Equations, Khalid Abdulaziz Alshammari Jan 2006

Filippov's Operator And Discontinuous Differential Equations, Khalid Abdulaziz Alshammari

LSU Doctoral Dissertations

The thesis is mainly concerned about properties of the so-called Filippov operator that is associated with a differential inclusion x'(t) ε F(x(t)) a.e. t ε [0,T], where F : Rn → Rn is given set-valued map. The operator F produces a new set-valued map F[F], which in effect regularizes F so that F[F] has nicer properties. After presenting its definition, we show that F[F] is always upper-semicontinuous as a map from Rn to the metric space of compact subsets of Rn endowed with the Hausdorff metric. Our main approach is to study the …


Multianalyte Detection Of Breast Cancer By Fabrication Of Hybridmicroarrays On Polymer-Based Microanalytical Devices, Suying Wei Jan 2006

Multianalyte Detection Of Breast Cancer By Fabrication Of Hybridmicroarrays On Polymer-Based Microanalytical Devices, Suying Wei

LSU Doctoral Dissertations

Breast cancer is one of the most common and fatal cancer diseases that affect women worldwide. As is true with most other cancer diseases, early detection of breast cancer is very crucial for proper medical treatment because treatment of advanced breast cancer will be much more difficult and inconsistent. Screening and testing of breast cancer biomarkers, either genetic or proteomic, are among techniques used for diagnosis of breast cancers. Nevertheless, none of the biomarkers is by itself sensitive and selective enough for diagnosis of breast cancer, and thus, multi-analyte assays towards detection of multiple breast cancer biomarkers from different classes …


Fabrication, Characterization And Properties Of Hiercchically Ordered Nanocomposites, Avinash Dundigalla Jan 2006

Fabrication, Characterization And Properties Of Hiercchically Ordered Nanocomposites, Avinash Dundigalla

LSU Doctoral Dissertations

The objectives of this research are to study the structure, morphology and properties of poly(ethylene-oxide) (PEO)-clay nanocomposites using various imaging techniques. Optical Microscopy, Scanning Electron Microscopy, Environmental Scanning Electron Microscopy and Atomic Force Microscopy are used to image structures on all length scales. Complementary scattering experiments are discussed along with preliminary differential scanning calorimetry and Fourier Transform Infrared spectroscopy results. In particular we investigated the multilayered structures of PEO-Laponite and PEO-Montmorillonite multilayered films made from solution. The shear orientation of a polymer-clay network in solution combined with simultaneous solvent evaporation leads to supramolecular multilayer formation in the film. The resulting …


Crystal Growth And The Search For Highly Correlated Ternary Intermetallic Antimonides And Stannides, Evan Lyle Thomas Jan 2006

Crystal Growth And The Search For Highly Correlated Ternary Intermetallic Antimonides And Stannides, Evan Lyle Thomas

LSU Doctoral Dissertations

This dissertation describes the crystal growth, chemical structures, and efforts made towards the understanding of the physical properties of novel ternary rare-earth intermetallics, which may display signature behavior such as superconductivity, heavy fermion behavior, intermediate valence, and/or large magnetoresistance. To address the problem of correlating these characteristics with structural features, several ternary antimony- and tin-containing phases, Ln-T-X (Ln = lanthanide; T = Co, Ni, Pd; X = Sn, Sb), have been synthesized in single crystalline form by metallic flux-growth methods and characterized by X-ray diffraction. The antimonide compounds LnNi1-xSb2 (Ln = Y, Gd-Tb, Er, Yb), alpha, beta-LnNiSb3 (Ln = La, …


Ab Initio Molecular Dynamics Simulations Of Methylaluminoxane (Mao) Synthesis By Hydrolysis Of Trimethylaluminum, Lacramioara Negureanu Jan 2006

Ab Initio Molecular Dynamics Simulations Of Methylaluminoxane (Mao) Synthesis By Hydrolysis Of Trimethylaluminum, Lacramioara Negureanu

LSU Doctoral Dissertations

MAO is the co-catalyst in the metallocene catalytic systems, which are widely used in single site olefin polymerization due to their high stereoselectivity. To date, the precise structure of MAO, the particular compound or compounds catalytically active in MAO, have eluded researchers. MAO, a white amorphous powder, is not a good sample for a direct spectroscopic characterization, and its NMR spectra are broad and almost featureless. Many structural models have been proposed but none are generally accepted. In the first part of this work the MAO formation mechanism was addressed. Molecular dynamics simulations at MP2 configuration interaction theory level have …


Development Of Analytical Techniques For The Analysis Of Submicron Particles And Protein Aggregates, Yohannes H. Rezenom Jan 2006

Development Of Analytical Techniques For The Analysis Of Submicron Particles And Protein Aggregates, Yohannes H. Rezenom

LSU Doctoral Dissertations

The goal of the research presented in this dissertation is to develop analytical techniques for the analysis of heterogeneous mixtures of submicron particles and protein aggregates. In Chapter 2, a simple and reproducible technique for constructing perfectly aligned gaps in fused-silica capillaries has been developed for postcolumn reagent addition with capillary electrophoresis (CE) to take advantage of laser-induced fluorescence (LIF) detection. This technique uses laser ablation with a Nd:YAG laser to create gaps of 14.0 ¡Ó 2.2 ƒÝm. These structures have been used for reagent addition for postcolumn derivatization with LIF detection and have been tested for the separation of …


Investigation Into The Dirhodium-Catalyzed Hydroformylation Of 1-Alkenes And Preparation Of A Novel Tetraphosphine Ligand, Alexandre R. Monteil Jan 2006

Investigation Into The Dirhodium-Catalyzed Hydroformylation Of 1-Alkenes And Preparation Of A Novel Tetraphosphine Ligand, Alexandre R. Monteil

LSU Doctoral Dissertations

The reaction of the tetraphosphine ligand rac-et,ph-P4 (et,ph-P4 = PEt2CH2CH2(Ph)PCH2P(Ph)CH2CH2PEt2) with 2 equiv. of [Rh(nbd)2]+ (nbd = norbornadiene) generates [rac-Rh2(nbd)2(et,ph-P4)]2+, which is the precursor to a highly active and regioselective hydroformylation catalyst system. The “key” catalyst species generated under H2/CO pressure has been proposed to be the dihydrido complex [rac-Rh2H2(ì-CO)2(et,ph-P4)]2+, and represents one of the most dramatic example of homobimetallic …


Simulating Protein Evolution Via Thermodynamic Models, Yanlong Xu Jan 2006

Simulating Protein Evolution Via Thermodynamic Models, Yanlong Xu

LSU Doctoral Dissertations

Natural proteins are results of evolution and they need to maintain certain thermodynamic stabilities in order to carry out their biological functions. By simulating protein evolution based on thermodynamic rules, we could reconstruct the evolution trajectory and analyze the evolutionary dynamics of a protein population, and further understand the protein sequence-structure-function relationship. In this study, we have used both a simplified lattice model and a high-resolution atomic model to simulate protein evolution processes. With the lattice model, we have investigated general theoretical questions about how protein structural designability would affect protein evolution, particularly how it would affect protein recombination and …


Syntheses And Biological Evaluation Of Water Soluble Carboranylporphyrins For Application In Boron Neutron Capture Therapy, Vijay Gottumukkala Jan 2006

Syntheses And Biological Evaluation Of Water Soluble Carboranylporphyrins For Application In Boron Neutron Capture Therapy, Vijay Gottumukkala

LSU Doctoral Dissertations

The goal of the research presented in this dissertation is to develop novel water soluble carboranylporphyrins that can deliver therapeutic dosage of boron specifically to tumors for application in boron neutron capture therapy. In order to accomplish this goal novel water soluble tetra(nido-carboranyl)porphyrin and the octa(nido-carboranyl)porphyrin with high boron contents are synthesized by the condensation of the carborane substituted benzaldehyde with the pyrrole under acidic conditions. These porphyrins are made water soluble by the deboronation of the closo-carboranes to afford the corresponding amphiphilic nido-carborane cages. The low cytotoxicity, high cellular uptake and intracellular localization of these carboranylporphyrins in tumor cells …


Synthesis, Crystal Growth, Magnetic And Transport Properties Of Ln-M-X (Ln=Lanthanide, M=Transition Metal, X=In, Ga) Compounds, Willa Maria Williams Jan 2006

Synthesis, Crystal Growth, Magnetic And Transport Properties Of Ln-M-X (Ln=Lanthanide, M=Transition Metal, X=In, Ga) Compounds, Willa Maria Williams

LSU Doctoral Dissertations

ABSTRACT This dissertation focuses on the structural stability, magnetic and transport properties of ternary lanthanide compounds grown using indium and gallium flux. Single crystals of TbRhIn5 were synthesized using indium flux. TbRhIn5 is isostructural to the well known LnnMIn3n+2 (n = 1, 2, ∞; Ln = La, Ce; M = Rh, Ir) and adopts the HoCoGa5 structure type and crystallizes in the space group P4/mmm, Z = 1. Lattice parameters are a = 4.6000(6) Å and c = 7.4370(11) Å, V = 157.29(6) Å3. A sharp antiferromagnetic transition is observed at TN = 48 K for TbRhIn5. Single crystals of …


Porous Inorganic-Organic Materials Based On Beta-Diketone Ligands, Yixun Zhang Jan 2006

Porous Inorganic-Organic Materials Based On Beta-Diketone Ligands, Yixun Zhang

LSU Doctoral Dissertations

Synthesis and characterization of porous inorganic-organic materials have been studied mainly on two linear β-diketone multifunctional ligands: pyridine based pyacH and isocyanide based HacphNC. As a known ligand, the preparation of pyacH has been improved with higher yield. When pyacH reacts with Fe and Al metal salts, trigonal metal β-diketonate building blocks M(pyac)3 are produced. When pyacH reacts with zinc acetate, both trans and cis Zn(pyac)2 are produced, both isomers were isolated and characterized by single-crystal X-ray crystallography. Solutions of the trigonal building block Fe(pyac)3 generate various crystal structures on reaction with AgNO3 in CH3CN. When the concentration of AgNO3 …


Application Of Polymeric Microfluidic Devices For Separation Of Single-Stranded Dna, Shawn Llopis Jan 2006

Application Of Polymeric Microfluidic Devices For Separation Of Single-Stranded Dna, Shawn Llopis

LSU Doctoral Dissertations

Microsystems targeted for DNA sequencing, especially those focused on electrophoretic separations, are rapidly proving their viability to genomic research, mimicking the progress made when capillary electrophoresis developed from miniaturizing slab gel electrophoresis techniques. Being the more recent electrophoretic separation platform, the commercial availability of microchip electrophoresis devices remains relatively limited. To this extent, high-aspect ratio microstructures formed in thermo plastics have been developed using rapid fabrication methods from molding tools designed for mass replication of high-aspect ratio microfeatures. In this work, the choice and compatibility of poly(methylmethacrylate) (PMMA) – the primary substrate for DNA separations in this work – was …