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Full-Text Articles in Physical Sciences and Mathematics

Breaking The Spell: Developing A New Generation Of Porphyrins For Treating Cerebral Tumors, Ryan Harrison Gray May 2009

Breaking The Spell: Developing A New Generation Of Porphyrins For Treating Cerebral Tumors, Ryan Harrison Gray

Honors Theses

No abstract provided.


Computational Studies On Fatty Acid Synthesis: From Mechanisms To Drug Design, Matthew Edward Mckenzie Jan 2009

Computational Studies On Fatty Acid Synthesis: From Mechanisms To Drug Design, Matthew Edward Mckenzie

LSU Doctoral Dissertations

The first committed steps of the Fatty Acid synthesis pathway involves the de/carboxylation reactions of biotin. By understanding this step, potential novel antimicrobial agents could be discovered. The current tools of drug discovery can only help the research in finding and modifying potential hits. Finding a lead candidate from these programs are often equated to finding a needle in a haystack, which is due to the many assumptions used in molecular docking. The fundamental reaction kinetics can not be described by these techniques and a detailed study of the decarboxylation reaction is investigated using ab initio molecular dynamics. In this …


Exploration Of Ternary Intermetallic Materials Using Tin And Gallium Flux, Edem Kodzo Okudzeto Jan 2009

Exploration Of Ternary Intermetallic Materials Using Tin And Gallium Flux, Edem Kodzo Okudzeto

LSU Doctoral Dissertations

The focus of this dissertation is the structure-property relationships of ternary intermetallic stannides and gallides. We are interested in these compounds because of the wide range of physical properties they possess. While investigating the Ln-Co-Sn system (Ln = lanthanide), we have synthesized single crystals that crystallize in the Yb3Rh4Sn13, Ho7Co6Sn23 and the Tb5Rh6Sn18 structure types. We observe the formation of a particular structure type depending on the size of the lanthanide present. The aforementioned compounds all contain CoSn6 trigonal prisms, which create voids occupied by Ln and Sn polyhedral units. We have also investigated the physical properties of these compounds …


Experimental Design, Synthesis And Application Of Molecular Micelle Modified Polymeric Nanoparticles For Drug Delivery Systems And Free Radical Detection, Gabriela M. Ganea Visser Jan 2009

Experimental Design, Synthesis And Application Of Molecular Micelle Modified Polymeric Nanoparticles For Drug Delivery Systems And Free Radical Detection, Gabriela M. Ganea Visser

LSU Doctoral Dissertations

Biodegradable and biocompatible polymeric nanoparticles such as poly (lactide-co-glycolide) (PLGA) nanoparticles have been extensively studied as drug delivery systems for a variety of pharmaceutical agents. Nanoparticle surface properties are primarily determined by the emulsifiers used in the synthesis process, which have a significant impact on nanoparticle physico-chemical and biological properties. Anionic amino acid – based molecular micelles were used in the emulsification process to prepare monodisperse, small (below 100 nm) PLGA nanoparticles with a well defined spherical shape. Such molecular micelle – modified nanoparticles were used as drug carriers for delivery of antioxidants. Thymoquinone is a natural antioxidant, and an …


Scanning Probe Microscopy Investigations Of (1) Arrays Of Cysteine-Coated Cds Nanoparticles And (2) Structures Formed During The Early Stages Of The Corrosion Of Copper Surfaces, Brian Robert Lewandowski Jan 2009

Scanning Probe Microscopy Investigations Of (1) Arrays Of Cysteine-Coated Cds Nanoparticles And (2) Structures Formed During The Early Stages Of The Corrosion Of Copper Surfaces, Brian Robert Lewandowski

LSU Doctoral Dissertations

Scanning probe microscopy (SPM) characterizations are becoming more prevalent for surface investigations due to their capabilities for obtaining structural information and physical measurements. New capabilities of SPM for studying and controlling nanoscale processes are emerging as valuable assets in research. A fundamental understanding of the interactions of surface reactions provides essential information for developing workable applications for nanotechnology. Two applications of SPM are discussed in this dissertation. The first investigation uses atomic force microscopy (AFM) for the characterization of nanostructures produced with a newly developed lithographic technique called “two-particle” lithography. This new technique is based on particle lithography for the …


Substituted Bis(Beta-Diketones) For Molecular Squares, Jace Sandifer Jan 2009

Substituted Bis(Beta-Diketones) For Molecular Squares, Jace Sandifer

LSU Master's Theses

Our group has been synthesizing porous supramolecular metal-organic molecules using multidentate β-diketones as ligands. For example, m-phenylenebis(acetylacetone) (m-pbaH2, 1) and m-phenylenebis(dipropionylmethane) (m-pbprH2, 2) were readily converted to the molecular squares Cu4(m-pba)4 (6) and Cu4(m-pbpr)4 (7), which bind guests such as 4,4’-bpy and C60.1 However, 6 and 7 are only soluble in a few solvents, limiting their use in practical applications. It is therefore necessary to derivatize the ligand with different functional groups in order to improve solubility and adjust host-guest properties. Simple alkoxy derivatives should prove useful in testing this idea as they would be relatively chemically inert and should …


Iron Mediated Pecipitation Of Phenol: Protein Aggregates From Sugar Cane Juice, Lee R. Madsen Ii Jan 2009

Iron Mediated Pecipitation Of Phenol: Protein Aggregates From Sugar Cane Juice, Lee R. Madsen Ii

LSU Doctoral Dissertations

The Louisiana cane sugar industry is moving toward a vertically integrated arrangement where raw sugar producers will have an interest in refining. In the sugar refining process, raw sugar is affined to remove ~50 % of the color. The new refinery that will be built in Louisiana, however, will not include affining stations. To reduce costs of refining, either affining stations will need to be installed at each mill or new technologies that provide equivalent color reduction (~50% or ~750 IU) need to be implemented. As part of this dissertation a new technology for color reduction at raw sugar mills …


Platforms And Protocols For The Multidimensional Microchip Electrophoretic Analysis Of Complex Proteomes, John K. Osiri Jan 2009

Platforms And Protocols For The Multidimensional Microchip Electrophoretic Analysis Of Complex Proteomes, John K. Osiri

LSU Doctoral Dissertations

The need for rapid, portable and high-throughput systems in proteomics is now prevalent because of demands for generating new protein-based disease biomarkers. However, 2-D protein profile patterns are lending themselves as potential diagnostic tools for biomarker discovery. It is difficult to identify protein biomarkers which are low abundant in the presence of highly abundant proteins, especially in complex biological samples like serum. Protein profiles from 2-D separation of the protein content of cells or body fluids, which are unique to certain physiological or pathological states, are currently available on internet databases. In this work, we demonstrate the ability to separate …


Achiral, Chiral, And Protein Separations With Molecular Micelles Using Chromatographic Techniques, Candace Ayanna Luces Jan 2009

Achiral, Chiral, And Protein Separations With Molecular Micelles Using Chromatographic Techniques, Candace Ayanna Luces

LSU Doctoral Dissertations

In this dissertation, several chromatographic techniques were developed for separation of proteins as well as achiral and chiral compounds. Firstly, polyelectrolyte multilayer (PEM) coatings were used to separate chiral analytes and proteins of pharmaceutical and biomedical interests. Coating polymers used in PEM coatings are instrumental in analyte separation. Therefore, the effect of changing four different cationic polymers, (poly-L-lysine, poly-L-ornithine, poly-L-lysine-serine, and poly-L-glutamic acid-lysine) and three anionic polymers (sodium poly (N-undecanoyl-L-leucyl-alaninate) (poly-L-SULA), sodium poly (N-undecanoyl-L-leucyl-valinate) (poly-L-SULV) and sodium poly (undecylenic sulfate) (poly-SUS)) were investigated. The simultaneous effects of cationic polymer concentration, number of bilayers, temperature, applied voltage, and pH of the …


Computational Studies Of The Properties Of Copper Oxide Clusters And The Reactions Of Phenol And Chlorinated Phenols With Copper Oxide Clusters, Gyun-Tack Bae Jan 2009

Computational Studies Of The Properties Of Copper Oxide Clusters And The Reactions Of Phenol And Chlorinated Phenols With Copper Oxide Clusters, Gyun-Tack Bae

LSU Doctoral Dissertations

We used ab initio simulations and calculations to study the structures and stabilities of copper oxide clusters, CunOn (n=1-8) and CuOn (n=1-6). The lowest energy structures of neutral and charged copper oxide clusters were determined using primarily the B3LYP/LANL2DZ model chemistry. In CunOn clusters with n=1-8, a transition from planar to nonplanar geometries occurs at n=4. In CuOn clusters with n=1-6, all geometries of neutral, positively, and negatively charged clusters are planar or near planar structures. Selected electronic properties, including binding energies, ionization energies, and electronic affinities, were calculated and examined as a function of n. Stabilities were examined by …


Atom-Based Computer Simulation Studies Of Gas-To-Liquid Nucleation In Atmospherically Relevant Systems: Clarifying Discrepancies And Elucidating Mechanisms, Ricky Bendanillo Nellas Jan 2009

Atom-Based Computer Simulation Studies Of Gas-To-Liquid Nucleation In Atmospherically Relevant Systems: Clarifying Discrepancies And Elucidating Mechanisms, Ricky Bendanillo Nellas

LSU Doctoral Dissertations

For over a century, nucleation for all systems was thought simplistically to be a process that advances through the formation of critical clusters with a well-defined composition. Our results show intriguing nucleation mechanisms that challenge the aforementioned notion. We employed the simple TraPPE-UA (transferable potential for phase equilibria – united atom) force field and the AVUS-HR approach (a combination of aggregation-volume-bias Monte Carlo, umbrella sampling, and histogram reweighting), to investigate the homogeneous vapor-to-liquid nucleation of various nucleating systems. We found out that these systems could nucleate through a variety of unique non-ideal mechanisms. Alongside existing experimental investigations, this dissertation presents …


Capillary Electrophoretic Separations Of Enzyme Inhibitors With Activity-Based Detection, Xiaoyan Yan Jan 2009

Capillary Electrophoretic Separations Of Enzyme Inhibitors With Activity-Based Detection, Xiaoyan Yan

LSU Master's Theses

A technique for separating and detecting enzyme inhibitors was developed using capillary electrophoresis with an enzyme microreactor. The on-column enzyme microreactor was constructed using one or two NdFeB magnets in two configurations to immobilize alkaline phosphatase-coated superparamagnetic beads with diameters of 2.8 µm inside a capillary before the detection window. Enzyme inhibition assays were performed by injecting a plug of inhibitor into a capillary filled with an alkaline phosphatase substrate, AttoPhos. Product generated in the enzyme microreactor was detected by laser-induced fluorescence. Inhibitor zones electrophoresed through the capillary, passed through the enzyme microreactor, and were observed as negative peaks due …


On-Line Laser Desorption/Ionization Mass Spectrometry, Damien A. Narcisse Jan 2009

On-Line Laser Desorption/Ionization Mass Spectrometry, Damien A. Narcisse

LSU Doctoral Dissertations

Interfaces for on-line laser desorption/ionization mass spectrometry are presented in this dissertation. An on line laser desorption interface allows samples to be introduced directly into the mass spectrometer for high-throughput applications. For this research, a linear time of flight mass spectrometer was constructed with an ionization source designed to accept various laser desorption interfaces. A ball inlet interface was used for continuous analyte deposition at atmospheric pressure and vacuum ionization. A solvent-based cleaning system and a separate capillary for MALDI matrix delivery was utilized for continuous on line sampling with the ball inlet interface. Microfluidic devices were brought into contact …


Polymer-Based Microfluidic Devices For High Throughput Single Molecule Detection: Applications In Biological And Drug Discovery, Paul Ichide Okagbare Jan 2009

Polymer-Based Microfluidic Devices For High Throughput Single Molecule Detection: Applications In Biological And Drug Discovery, Paul Ichide Okagbare

LSU Doctoral Dissertations

The realization of high throughput sample processing has become a primary ambition in many research applications with an example being high throughput screening (HTS), which represents the first step in the drug discovery pipeline. Microfluidics is a viable platform for parallel processing of biochemical reactions to increase data production rates due to its ability to generate fluidic networks with a high number of processors over small footprints suitable for optical imaging. Single-molecule detection (SMD) is another technology which has emerged to facilitate the realization of high throughput data processing afforded by its ability to eliminate sample processing steps and generate …


Applying Scanning Probe Microscopy For The Investigation Of Molecular Self-Assembly Mechanisms And Properties Of Designed Nanomaterials, Algernon Tremayne Kelley Jan 2009

Applying Scanning Probe Microscopy For The Investigation Of Molecular Self-Assembly Mechanisms And Properties Of Designed Nanomaterials, Algernon Tremayne Kelley

LSU Doctoral Dissertations

Scanning probe microscopy (SPM) for conducting surface characterizations of nanomaterials and molecular self-assembly processes is emerging as an important contribution in nanotechnology, especially towards the design of molecular electronic devices. Another area of importance is the characterization of the properties of nanomaterials for fundamental understanding of structure-function inter-relationships. Understanding the properties and behavior of molecules and finding approaches to control surface self-organization through nanolithography provides essential information for the development of workable applications for nanotechnology. This dissertation describes the methodologies of AFM for characterizing molecules and nanostructures produced with scanning probe lithography (SPL). Automated software for nanografting and nanoshaving produce …


Studies Of Homogeneous Dirhodium Catalyst System, Catherine L. Thomas Alexander Jan 2009

Studies Of Homogeneous Dirhodium Catalyst System, Catherine L. Thomas Alexander

LSU Doctoral Dissertations

Hydroformylation studies were conducted to investigate the effects of various H&sub2;/CO ratios on rac-[Rh&sub2;H&sub2;(μ-CO)&sub2;(et,ph-P4)]²+;, a dirhodium tetraphosphine catalyst system. Similar experiments were also conducted with monometallic catalysts based on BISBI, NAPHOS, and Xantphos, some of the best bisphosphine ligands for hydroformylation catalysis. This was due to the lack of information in literature on the effects of variable ratios and pressures on activities and selectivities of catalysts that contain bisphosphine ligands, and these studies were also used as a basis of comparison for the dirhodium system. Results indicate that the dirhodium system is more efficient with higher H&sub2;/CO ratios (2:1, 90 …


Amyloid Aggregation-Mitigating Peptides As Potential Alzheimer's Drugs, Cyrus Kipkurui Bett Jan 2009

Amyloid Aggregation-Mitigating Peptides As Potential Alzheimer's Drugs, Cyrus Kipkurui Bett

LSU Doctoral Dissertations

Neuronal cytotoxicity observed in Alzheimer¡¦s disease (AD) is linked to the aggregation of £]-amyloid peptide (A£]) into toxic forms. Increasing evidence points to oligomeric species as the neurotoxic species compared to fibrils; disruption or inhibition of A£]ƒnself-assembly into oligomeric or fibrillar forms remains a viable therapeutic strategy to reduce A£] neurotoxicity. Amyloid aggregation mitigating peptides (AAMPs) were designed based on the A£]ƒn¡§hydrophobic core¡¨ A£]17-20, with C£\,£\-disubstituted amino acidsƒnƒv£\£\AAs) added into this core as disrupting agents. The number, distribution, and side chain functionality of £\£\AAs incorporated into the mitigator sequence was found influences the resultant aggregate morphology as indicated by ex-situ …


Merged Electrospray Ionization Mass Spectrometry, Jianan Dong Jan 2009

Merged Electrospray Ionization Mass Spectrometry, Jianan Dong

LSU Doctoral Dissertations

Ambient ionization allows the analysis of materials in their native environment without sample preparation by creating ions outside the mass spectrometer. The goal of this research was to develop new ambient ionization techniques for application to solids, liquids and particles under ambient conditions. Samples to be analyzed were directly merged with an electrospray of droplets, and then ionized and detected by a mass spectrometer. An ion trap mass spectrometer was modified with a nanoelectrospray source and configured for three experiments: merged electrospray ionization of dry particles, merged electrospray ionization of combustion products, and infrared laser desorption/ablation using electrospray for post-ionization. …


Size Controlled Metal Oxide Nanoparticles:Synthesis, Characterization, And Application To Catalysis, Hongyi Wu Jan 2009

Size Controlled Metal Oxide Nanoparticles:Synthesis, Characterization, And Application To Catalysis, Hongyi Wu

LSU Doctoral Dissertations

The research in this dissertation focuses on the synthesis of size-controlled metal oxide nanoclusters (< 10 nm) on amorphous silica and their catalytic performance in thermal degradation of chlorinated benzenes with regard to the cluster size effect. Furthermore, with the concern that metal can condense as the nano-size nuclei core for particle growth in combustion process, a flow reactor was built to investigate the effect of metal oxide nanoparticles on the formation of soot in fuel-rich combustion. The synthesis of copper oxide nanoclusters was carried by calcination of silica impregnated with dendrimer-metal complexes. The 4th generation poly(propylene imine) dendrimer DAB-Am32 was used in this template-based method. The sizes of copper oxide nanoclusters were exquisitely controlled in the range of 1-5 nm with narrow size distribution by changing the stoichiometric ratio of metal ion to the terminal primary amines of dendrimer, the equivalent metal oxide loading on surface, and the impregnation procedure. XANES and XPS studies revealed that CuO was the dominant component of copper oxide nanoclusters. This method was also experimentally proven to be valid in the preparation of other metal oxide nanoparticles, e.g., Ni and Fe, and with other oxide substrates, e.g., titanium oxide. Chlorinated benzenes were selected as the model compound for studying the activity of metal (Cu and Fe) oxide catalysts with regard to their cluster sizes. Compared to the surrogate of coarse metal oxide samples, which was prepared by incipient wetness method, their nanosize analogues showed superior catalytic activity on the conversion of chlorinated benzenes under both pyrolytic and oxidative thermal condition. Furthermore, such catalytic size effect was also observed on the selectivity of products yields. Sooting combustion was performed using a two-zone flow reactor with precise control on experimental parameters. Gas suspended metal oxide nanoparticles were generated by burning off the organic backbone of the dendrimer-metal complexes in zone 1 and immediately transferred to zone 2, where the hydrocarbon combustion occurred. TEM results of the particulate sample collected at the outlet of reactor indicated that metal oxide nanoparticles promoted soot formation. GC/MS analysis of the extracted organic materials from soot samples suggested the formation of PAH was also promoted by metal addition as well.


The Syntheses Of Methyl Jasmonate And Analogs Of Alpha-Methylene-Gamma-Butyrolactone Utilizing Titanium Medicated Cyclocarbonylation, Steve O. Lawrence Jan 2009

The Syntheses Of Methyl Jasmonate And Analogs Of Alpha-Methylene-Gamma-Butyrolactone Utilizing Titanium Medicated Cyclocarbonylation, Steve O. Lawrence

LSU Doctoral Dissertations

From its humble beginnings as a novel carbon–carbon bond forming reaction, the Pauson–Khand reaction has lead to the synthetic development of a variety of natural products. One particular variation of the Pauson–Khand reaction was called the hetero Pauson–Khand. This reaction differs from the normal Pauson–Khand reaction because the reaction employs an intramolecular titanium mediated cycloaddition using enal and enones instead of alkenes and alkynes functional groups to prepare a variety of natural products. These natural products usually contain a bicyclic cyclopentenone core. Because the new ring contains a hetero atom, the name hetero Pauson–Khand was coined. Alpha–Methylene–Gamma–Butyrolactones posses a wide …


Task Specific Ionic Liquids For Enantiomeric Recognition And Nanomaterials For Biomedical Imaging, David Kipkogei Bwambok Jan 2009

Task Specific Ionic Liquids For Enantiomeric Recognition And Nanomaterials For Biomedical Imaging, David Kipkogei Bwambok

LSU Doctoral Dissertations

Ionic liquids (ILs) are organic salts that melt at or below 100°C. Interest in ILs continues to grow due to their unique properties such as lack of measurable vapor pressure, high thermal stability, tunability and recyclability. The first part of this dissertation explores the use of chiral ionic liquids (CILs) for enantiomeric recognition of chiral analytes using fluorescence spectroscopy. Chiral analyses continue to be a subject of considerable interest primarily as a result of legislation introduced by the Food and Drug Administration. This has led to an increased need for suitable chiral selectors and methods to verify the enantiomeric forms …


Phytochemical Analyses Of Bioactive Compounds In The Roots Of Cassia Alata Linn And The Anti-Angiogenic Evaluation Of Rhein As A Therapeutic Agent Against Breast Cancer Cells, Vivian Esther Fernand Jan 2009

Phytochemical Analyses Of Bioactive Compounds In The Roots Of Cassia Alata Linn And The Anti-Angiogenic Evaluation Of Rhein As A Therapeutic Agent Against Breast Cancer Cells, Vivian Esther Fernand

LSU Doctoral Dissertations

The research presented in this dissertation includes the novel phytochemical analysis of root extracts of Cassia alata L. and the anti-angiogenic evaluation of rhein in the treatment of breast cancer. To conduct these studies a combination of analytical techniques were employed, namely, chromatographic, spectroscopic, and bioanalytical. The first part of this research is focused on the phytochemical analysis of C. alata root extracts. A high performance liquid chromatography method was developed and validated for the determination of six phenolic compounds in the root extracts. The investigated compounds were identified by their ultraviolet spectra. Additionally, the presence of these phenolics was …


A Study Of The Self-Assembly Of Water-Soluble Porphyrins In Aqueous Solution, Javoris Hollingsworth Jan 2009

A Study Of The Self-Assembly Of Water-Soluble Porphyrins In Aqueous Solution, Javoris Hollingsworth

LSU Master's Theses

In nature, self-assembly processes of biologically active organic molecules often occur, resulting in formation of dimers and higher oligomers of various and sometimes complex structures. This natural occurrence of self-organization has been the subject of research, with the aim of understanding and possibly modulating the aggregation behavior of biological molecules. The meso-tetrakis(4-phosphonatophenyl) porphyrin, H2TPPP was synthesized, purified, and characterized. Its self-assembly was studied in aqueous solutions as a function of pH and time. The variations on the λmax and shape of the Soret band of this porphyrin in the absorption spectra when altering the pH indicated the pH dependency in …


Single-Molecule Detection Of Unique Genome Signatures: Applications In Molecular Diagnostics And Homeland Security, Jason M. Emory Jan 2009

Single-Molecule Detection Of Unique Genome Signatures: Applications In Molecular Diagnostics And Homeland Security, Jason M. Emory

LSU Doctoral Dissertations

Single-molecule detection (SMD) offers an attractive approach for identifying the presence of certain markers that can be used for in vitro molecular diagnostics in a near real-time format. The ability to eliminate sample processing steps afforded by the ultra-high sensitivity associated with SMD yields an increased sampling pipeline. When SMD and microfluidics are used in conjunction with nucleic acid-based assays such as the ligase detection reaction coupled with single-pair fluorescent resonance energy transfer (LDR-spFRET), complete molecular profiling and screening of certain cancers, pathogenic bacteria, and other biomarkers becomes possible at remarkable speeds and sensitivities with high specificity. The merging of …


Peptide Targeting Of Platinum Anti-Cancer Drug And Synthesis Of Water Soluble Monofunctional Pt(Ii) Complexes Useful For Biological Labeling, Margaret W. Ndinguri Jan 2009

Peptide Targeting Of Platinum Anti-Cancer Drug And Synthesis Of Water Soluble Monofunctional Pt(Ii) Complexes Useful For Biological Labeling, Margaret W. Ndinguri

LSU Doctoral Dissertations

Platinum has been used as an inorganic medicinal agent with various applications such as anti cancer agents. Several new targeted Pt(II) conjugates were synthesized having the NGR and LHRH targeting motif. The platinum conjugates bearing the NGR motif revealed selective delivery and destruction of cancer cells that had CD13 receptors compared to untargeted carboplatin drug. The development of targeted chemotherapeutic has opened a new approach for efficient delivery of antitumor toxins with minimal exposure to normal cells. Several peptide sequences are known to have the ability to target tumors, for instance NGR motif which home specifically in solid tumors and …


Synthesis And Characterization Of Transition Metal And Metal Oxide Nanoparticles Using Dendritic Complexes, Elisabeta Mitran Jan 2009

Synthesis And Characterization Of Transition Metal And Metal Oxide Nanoparticles Using Dendritic Complexes, Elisabeta Mitran

LSU Doctoral Dissertations

The research in this dissertation focuses on the synthesis and characterization of metal/metal oxide nanoparticles in solution and on surfaces with a high degree of control over size and size dispersity; such well-defined nanoparticles were made using metal ion-dendrimer complexes and silica-supported organometallic dendrimers. The metal oxide-based materials can be used as laboratory surrogates for combustion-generated nanoparticles to assess their role in mediating pollutant formation. Nickel nanoparticles with low size dispersity were prepared by a dendrimer-ligand-based method employing five generations amine-terminated poly(propylene imine) dendrimer, DAB-Amn. After coordination, borohydride reduction of Ni(II) ion-dendrimer complexes yielded Ni(0) nanoparticles, as determined by X-ray …


Beta-Diketone And -Ketoenamine-Based Organic Building Blocks For Porous Metal Organic-Materials, Yoseph Solomon Marcos Jan 2009

Beta-Diketone And -Ketoenamine-Based Organic Building Blocks For Porous Metal Organic-Materials, Yoseph Solomon Marcos

LSU Doctoral Dissertations

This dissertation focuses on synthesis of multifunctional â-diketone and â-ketoenamine ligands and their reaction with metal ions, mainly Cu2+. Several new bi-, tri-, and tetrafunctional organosilicon â-diketone building blocks with â-diketone groups at approx. 109° (tetrahedral) were successfully synthesized. New thiophene based bifunctional ligands where the â-diketones are at about 145° are also reported here. We also prepared a range of new aryl-â-ketoenamines from their analogous â-diketones in very high yield using a simple microwave-assisted procedure. Reactions of organosilicon tris(â-diketone)s LH3 with Cu2+ were explored quite intensively. These ligands form metal-organic-polyhedra (MOPs) that are soluble in organic solvents, and insoluble …


Studies On The Effect Of Natural Organic Matter And Hydration On The Sorption And Desorption Of Trifluorinated Pesticides, Charisma Vinarao Lattao Jan 2009

Studies On The Effect Of Natural Organic Matter And Hydration On The Sorption And Desorption Of Trifluorinated Pesticides, Charisma Vinarao Lattao

LSU Doctoral Dissertations

This work was done in order to deepen our molecular level understanding of how soil organic matter (SOM) is assembled in a whole soil and to provide further insight on the effect of SOM assembly on the uptake and release of hydrophobic organic compounds. Various techniques, including ultraviolet absorbance, fluorescence, and total carbon analysis, demonstrate that hydration/solvation of SOM is kinetically controlled. Initial wetting of a soil releases the hydrophobic moieties that are located at the outer surface of SOM, and longer wetting times exfoliate more hydrophobic quinone type moieties that are present in the middle layer, which in turn …


A Novel Synthesis And Characterization Of Fluorescein Isothiocyanate Labeled Poly(Styrenesulfonate Sodium Salt), Xiaowei Tong Jan 2009

A Novel Synthesis And Characterization Of Fluorescein Isothiocyanate Labeled Poly(Styrenesulfonate Sodium Salt), Xiaowei Tong

LSU Master's Theses

The diffusion of polyelectrolytes in low-salt or salt-free aqueous solutions is a controversial question. It has been intensively discussed since it was discovered in 1978. Most previous experimental data were obtained from dynamic light scattering (DLS), whose precision, however, was reduced by stringent sample preparation and weak scattering of polyelectrolyte in low-salt solution. For the most commonly studied polyelectrolyte, poly(styrenesulfonate sodium salt) (NaPSS), the harsh polymerization condition and the manufacturing procedure lead to hydrophobic defects and aggregations, which also block a correct insight about the diffusion of polyelectrolyte. In contrast to DLS, fluorescence photobleaching recovery (FPR) directly looks on the …


Fabrication Of Nanostructured Surfaces With Well-Defined Chemistry Using Particle Lithography, Jie-Ren Li Jan 2009

Fabrication Of Nanostructured Surfaces With Well-Defined Chemistry Using Particle Lithography, Jie-Ren Li

LSU Doctoral Dissertations

Natural self-assembly processes provide nanofabrication capabilities for designing surfaces with nanoscale control of surface chemistry and relative orientation of the nanomaterials on the surfaces. Particle lithography was used to produce periodic arrays of protein nanostructures. Monodisperse mesoparticles can be applied to rapidly prepare millions of uniform protein nanostructures on flat surfaces using the conventional benchtop chemistry steps of mixing, centrifuging, evaporation and drying. Nanopatterns of bovine serum albumin and staphylococcal protein A were produced with particle lithography. The immobilized proteins remain attached to the surface and form nanopatterns over micron areas corresponding to the thickness of a single layer of …