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Solid State Energy Barriers To Olefin Ligand Rotation Of Rhodium Compounds And Single Crystal X-Ray Structure Determination Of Synthetic And Natural Products., Yen-Hsiang Liu
LSU Historical Dissertations and Theses
Atomic displacement parameters (ADPs) were derived from X-Ray diffraction data collected at two different temperatures (294K and 115K) from a single crystal of Rh(acac)(C$\rm\sb2H\sb4)\sb2.$ Since the thermal ellipsoids of atoms in the one crystallographically independent ethylene group displayed distinctive elongation normal to the C=C bond, a TLS rigid body analysis of the $\rm C\sb2H\sb4$ ligand rotation was undertaken. Using a locally modified version of Trueblood's THMA14 computer program, it was found that at 115K the root-mean-square amplitude of libration normal to the Rh-(CC centroid) axis is $7(4)\sp\circ,$ while at 294K it is $10(6)\sp\circ$ (estimated standard deviations in parentheses). The rotational …
Towards Bimetallic Asymmetric Hydroformylation Catalysis: Separation Of The Diastereomers And Enantiomers Of A Binucleating Tetraphosphine Ligand., Pia Rosario Alburquerque
Towards Bimetallic Asymmetric Hydroformylation Catalysis: Separation Of The Diastereomers And Enantiomers Of A Binucleating Tetraphosphine Ligand., Pia Rosario Alburquerque
LSU Historical Dissertations and Theses
The separation of the racemic and meso diastereomers of the binucleating ligand et,ph-P4 ((Et$\rm \sb2PCH\sb2CH\sb2)(Ph)PCH\sb2P(Ph)(CH\sb2CH\sb2PEt\sb2))$ was achieved. The thiocyanate nickel(II) complexes of mixed racemic- and meso-et,ph-P4 were separated based on their different solubilities in ethanol. Cyanolysis of the separated racemic and meso nickel(II) complexes allowed the recovery of the free racemic- and meso-et,ph-P4 ligands. The many species involved in this process were identified in order to obtain consistent and improved results. After the separation of the diastereomers, the enantiomers of racemic-et,ph-P4 were separated in order to study the ability of the bimetallic chiral rhodium et,ph-P4 complexes to act as precursors …
Electrochemical And Spectroscopic Studies Of Boron And Sulfur Species In Nonaqueous Media., Jianzhong Liu
Electrochemical And Spectroscopic Studies Of Boron And Sulfur Species In Nonaqueous Media., Jianzhong Liu
LSU Historical Dissertations and Theses
Room temperature molten salts have been of interest because of their unique properties such as aprotic nature and excellent Lewis acid-base adjustability. They provide a novel medium for fundamental studies and constitute a promising electrolyte for metal plating and secondary batteries. In the present study, the room temperature N-Butyl-pyridinium chloride (BPC)-boron trichloride (BCl$\sb3)$ and mixed BCl$\sb3$-AlCl$\sb3$-BPC melts have been prepared and characterized using reaction stoichiometries, electrochemistry and secondary ion mass spectrometry (SIMS). At normal atmosphere and room temperature, even when excess BCl$\sb3$ was added, BCl$\sb3$-BPC melts have a constant composition of 52:48 mole ratio BCl$\sb3$:BPC. SIMS studies confirmed previous Raman …
Peroxynitrite Mediated Oxidations: Spin Trap Studies; Nitration And Hydroxylation Of Phenol Result From Different Intermediates; Co(2) Catalyzes The Decomposition Of Peroxynitrite., Jean-Noel Lemercier
Peroxynitrite Mediated Oxidations: Spin Trap Studies; Nitration And Hydroxylation Of Phenol Result From Different Intermediates; Co(2) Catalyzes The Decomposition Of Peroxynitrite., Jean-Noel Lemercier
LSU Historical Dissertations and Theses
In the first project the spin trap DMPO was used to probe for the production of hydroxyl radicals from peroxynitrite. Peroxynitrite reacts with DMPO to give $\sp\cdot$DMPO-OH, suggesting that $\sp\cdot$DMPO-OH results from a reaction between DMPO and HOONO or between DMPO and an activated intermediate of HOONO. Thiols produce a large increase in the $\sp\cdot$DMPO-OH signal intensity. Experiments employing SOD suggest that this increase results from the decomposition of $\sp\cdot$DMPO-OOH. These results are incompatible with the decomposition of peroxynitrite to form $\sp\cdot$OH but suggest that an intermediate of HOONO is produced that is less reactive and more selective than the …
Syntheses, Separations, And Applications Of Water-Soluble Chiral Calixarenes., Yuling Zhang
Syntheses, Separations, And Applications Of Water-Soluble Chiral Calixarenes., Yuling Zhang
LSU Historical Dissertations and Theses
This dissertation focuses on the study of water-soluble calixarene derivatives as receptors for fluorescence probes and as chiral selectors. The synthesis of sulfonated calixarenes was first pursued and a method for the separation of sulfonated calixarenes (4), (6), (8) and the 4-hydroxylbenzene sulfonate monomer by capillary zone electrophoresis with direct UV absorbance detection is described. Fluorescence and absorption studies of water-soluble sulfonated calix(6)arene (SCX6) are reported. A red shift in the absorption spectrum and a change in the fluorescence spectrum of the calixarenes are observed upon an increase in pH from 2.0 to 13.0. The spectroscopic changes are attributed to …
Characterization Of The Cytochromes P450-Dependent Hepatic Microsomal Monooxygenase System Of The American Alligator, Alligator Mississippiensis: Influence Of Xenobiotic Chemicals., Robin Parsons Ertl
Characterization Of The Cytochromes P450-Dependent Hepatic Microsomal Monooxygenase System Of The American Alligator, Alligator Mississippiensis: Influence Of Xenobiotic Chemicals., Robin Parsons Ertl
LSU Historical Dissertations and Theses
Alligator mississippiensis contains all of the components of the hepatic microsomal mixed function oxidase system. In general, basal and induced levels of P450 specific content, immunochemically detected abundance and examined activities are less than in mammals. In alligator at least two classes of P450s are inducible by xenobiotics: those induced by 3-methylcholanthrene (3MC) and those induced by phenobarbital (PB). PB and 3MC induce multiple P450 isoforms as detected by western blot and enzymatic analyses. The induced level of alkoxyphenoxazone O-dealkylation (AROD) was 10- to 100-fold lower in alligator than in rat, with the exception of phenylbenzyloxyphenoxazone O-dealkylation. In contrast to …
Characterization Of Monomer-Containing Monolayer Films On Au Surfaces., Robert J. Willicut
Characterization Of Monomer-Containing Monolayer Films On Au Surfaces., Robert J. Willicut
LSU Historical Dissertations and Theses
Exploration into the nature of ultrathin, surface-confined films capable of electronic conduction has been the primary purpose of this dissertation. Specifically, the confinement of pyrrole monomer to Au surfaces through organosulfur linkages has been investigated. The synthesis of these new $\omega$-(N-pyrrolyl)alkanethiols is described herein. Cyclic voltammetry was utilized in this work to polymerize the monolayers and characterize the resulting films. Voltammetric analysis yielded currents in the correct potential region for poly(N-alkylpyrrole) charging/discharging. Other electrochemical studies revealed the ability of strong nucleophiles and electroinactive diluents to quench surface-confined polymer formation though they did not affect oxidation of the monomer. Exchange experiments …
Preparation Of Strained Nitrogen Heterocycles For Spin Trapping Applications., Anna Patrice Shanklin
Preparation Of Strained Nitrogen Heterocycles For Spin Trapping Applications., Anna Patrice Shanklin
LSU Historical Dissertations and Theses
This work discusses the synthesis of bicyclic nitrogen heteorocycles with the emphasis placed on the design and evaluation of a bicyclic nitrone for spin trapping applications. Camphorolactams, 1,7,7-trimethyl-2-aza-bicyclo(2.2.1) heptan-3-one and 1,7,7-trimethyl-3-azabicyclo (2.2.1) heptan-2-one were prepared from camphoric anhydride under Curtius conditions with sodium azide and dimethylformamide. 2-azabicyclo(2.2.1) heptan-3-one was also prepared under Curtius conditions from cis-1,3-cyclopentane-dicarboxylic acid anhydride. N-benzyl-2-azabicyclo (2.2.1) -heptane and N-benzyl-2-azabicyclo (2.2.2) octane were prepared from their aliphatic amine derivatives under Hofmann-Loeffler conditions in low yields. 1,3,3-trimethyl-6-azabicyclo (3.2.1) octane, N-oxide was prepared from its parent amine under sodium tungstate catalyzed oxidation with hydrogen peroxide. The bicyclic nitrone was …
Synthesis Of Novel Cyclopentadienyl And Pyrrole Compounds., Alfonso Davila
Synthesis Of Novel Cyclopentadienyl And Pyrrole Compounds., Alfonso Davila
LSU Historical Dissertations and Theses
This dissertation describes the preparation of two classes of compounds: cyclopentadienes and pyrroles. These compounds are key elements in the synthesis of conducting materials. A general novel methodology for the cyclopentadienylannulation of strained cycloalkynes has been developed. Bromination of 1,5-cycloctadiene produces 1,2,5,6-tetrabromocyclooctane, which under further treatment with DBU eliminates two moles of HBr to produce a mixture of 2 diastereomeric bisvinylbromides. These isomers eliminate one mol of HBr when treated with t-BuOK under phase transfer conditions producing a cyclooctene-yne. This bromoalkyne reacts in situ with dimethylfulvene in a sealed tube at 100$\sp\circ$C to produce a Diels-Alder adduct. Treatment of this …
Characterization Of Bean Eukaryotic Translation Initiation Factor 5: Cloning, Sequencing, And Structure-Function Studies., Zelpha Elizabeth Floyd
Characterization Of Bean Eukaryotic Translation Initiation Factor 5: Cloning, Sequencing, And Structure-Function Studies., Zelpha Elizabeth Floyd
LSU Historical Dissertations and Theses
Translation initiation is emerging as one of the important mechanisms involved in regulation of gene expression and our understanding of this process in eukaryotes has greatly increased over the past twenty years. Research in translation initiation in plants has lagged behind efforts in the mammalian system and a number of the initiation factors have not been characterized. Eukaryotic initiation factor 5 (eIF5), the protein mediating hydrolysis of the eIF2-bound GTP and the subsequent formation of the 80S ribosome, is among the least characterized initiation factor in plants. This dissertation describes the cloning of the cDNA encoding eIF5 from a bean …
New Developments In Portable Fast Gas Chromatography., Elena Ursula Ehrmann
New Developments In Portable Fast Gas Chromatography., Elena Ursula Ehrmann
LSU Historical Dissertations and Theses
Currently commercially available portable gas chromatographs are suitable only for the analysis of volatile organic compounds, and do not include temperature programming capability. This dissertation presents the development of a novel direct at-column heater design and a pressure driven injection system that is compatible with semi-volatile analytes. The collinear and coaxial at-column heater designs incorporate heater and temperature sensing elements placed along the column. Resistive heating controls the column temperature via a feedback circuit and a software selected program. Linear temperature programming ramps up to 14$\sp\circ$C/s were obtained, with a total power consumption of less than 100 Watt. The accuracy …
Identification Of The Physiological Role Of Carbonic Anhydrase Using The Antisense Technique, And, Investigation Of Its Transcriptional Regulation In Arabidopsis Thaliana (L.) Heynh., Hee Jin Kim
LSU Historical Dissertations and Theses
Carbonic anhydrase (CA, EC 4.2.1.1), catalyzes the interconversion of CO$\sb2$ and $\rm HCO\sb3\sp-$ in many organisms. The majority of CA activity in C3 leaves is in the chloroplast and expression of the chloroplast CA is regulated by light. To investigate the physiological role of the chloroplast CA, its expression was suppressed by insertion of a CA transgene in the antisense orientation in Arabidopsis thaliana (L.) Heynhold. Activity assays and immunoblots show that in five independent lines of antisense transgenic plants CA activity was strongly suppressed. All five independent lines died or grew poorly in the absence of sucrose whereas wild …
Characterization Of Aminoalkylcarbamoyl Cellulosic And Chitosan Derivatives For Use In Cosmetic Formulation., Melissa Ann Manuszak Guerrini
Characterization Of Aminoalkylcarbamoyl Cellulosic And Chitosan Derivatives For Use In Cosmetic Formulation., Melissa Ann Manuszak Guerrini
LSU Historical Dissertations and Theses
Polymer and surfactant interactions have been a subject of intense research due to industrial applications utilizing a polymer-surfactant system, such as cosmetic formulation. A series of aminoalkylcarbamoyl cellulose derivatives were prepared from the amidation of methylcarboxymethyl cellulose. These derivatives were quaternized with either iodomethane, or hydroxypropyl trimethylammonium chloride, or epichlorohydrin and dimethylamine to yield polyquaternary ammonium salts. The focus of this dissertation is the characterization of a family of these compounds based on N,N$\sp\prime$,-dimethylethylene diamine. As these compounds are similar to Polyquaternium 10, a quaternized hydroxyethyl cellulose derivative, the solution properties have been characterized; antimicrobial activity and keratin affinity have …
Structure-Activity Relationships Of Nitroarenes: Mutagenicity, Oxygen Consumption, Toxicity, And Xenobiotic Radical Production., Caroline Ann Metosh-Dickey
Structure-Activity Relationships Of Nitroarenes: Mutagenicity, Oxygen Consumption, Toxicity, And Xenobiotic Radical Production., Caroline Ann Metosh-Dickey
LSU Historical Dissertations and Theses
The nitroreduction of 4NQO and five structural analogs were studied with respect to radical production and mutagenicity. In the umu assay, 4NQO was the most mutagenic analog. Addition of microsomal and cytosolic protein from induced and uninduced rat liver samples decreased 4NQO mutagenicity in the standard strain (Salmonella typhimurium TA 1535/psk1002) 4NQO mutagenicity was also found to be decreased in the nitroreductase-deficient strain (Salmonella typhimurium TA1535NR/psk1002). In several strains of the Protox$\rm\sp{TM}$ assay 4NQO yielded the highest induction rate as compared to other compounds tested. In the presence of ascorbate 4NQO cytotoxicity, but not mutagenicity, was substantially enhanced. Oxygen consumption …
Spectroscopic Analyses Of Excited-State Phenomena In Organized Media: Proton Transfer And Photoisomerization And Measurement Of Modified Low Density Lipoproteins Using Rapid-Mixing Multidimensional Stopped-Flow Spectroscopic Methods., Eric Lamar Butler-Roberts
Spectroscopic Analyses Of Excited-State Phenomena In Organized Media: Proton Transfer And Photoisomerization And Measurement Of Modified Low Density Lipoproteins Using Rapid-Mixing Multidimensional Stopped-Flow Spectroscopic Methods., Eric Lamar Butler-Roberts
LSU Historical Dissertations and Theses
The research presented in this dissertation generally involves aspects of molecular spectroscopy and contains two areas of focus. In the first section, the influences of organized media on the excited-state phenomena of intramolecular proton transfer (ESIPT) and photoisomerization have been investigated. Specifically, the photochemical properties of the novel ESIPT molecule 10-hydroxybenzo(h) quinoline (HBQ), as well as 2-(2$\sp\prime$-hydroxyphenyl)benzazoles (HBAs), have been examined in the presence of cyclodextrins (CDs) and micelles using absorbance, steady-state, and time-resolved emission spectroscopies. Additionally, the influence of cyclodextrins upon the photoisomerization of trans-stilbene (TS) has been studied. Results from spectroscopic studies of HBQ and HBAs in organized …
The Synthesis Of Novel Phosphine-Modified Ligands For Use In Bimetallic Hydroformylation., Howard Frederick Koch Iii
The Synthesis Of Novel Phosphine-Modified Ligands For Use In Bimetallic Hydroformylation., Howard Frederick Koch Iii
LSU Historical Dissertations and Theses
The tetraphosphine ligand, Et$\sb2$P(CH$\sb2)\sb2$P(Ph)CH$\sb2$P(Ph)(CH$\sb2)\sb2$PEt$\sb2 ,$ et,ph-P4, was designed to be a binucleating ligand for use in bimetallic hydroformylation catalysis. This ligand can be tailored for both electronic and steric factors at the internal and external phosphorus atoms. It is hoped that through careful tuning of this ligand, the rate and selectivity of our bimetallic catalyst can be optimized for various substrates. Modification of the original ligand may also lead us to a better understanding of the mechanism involved in the catalytic cycle. My goal has been to replace the phenyl substituents on the internal phosphorus atoms with various alkyl groups. …
Synthesis And Photophysical Characterization Of Near-Ir Probes For Bioanalytical Applications., James Henry Flanagan Jr
Synthesis And Photophysical Characterization Of Near-Ir Probes For Bioanalytical Applications., James Henry Flanagan Jr
LSU Historical Dissertations and Theses
The research presented in this dissertation involves the synthesis and photophysical characterization of a series of tricarbocyanine dyes which can be used as fluorescent labels for bioanalytical applications. All of these dyes were synthesized to contain a heavy-atom modification to enhance k$\sb{\rm isc}$ through spin-orbit coupling and a functional group (isothiocyanate or succinimidyl ester) which is reactive towards primary amines. The spectroscopic characterization of the various chromophores was examined using absorbance and fluorescence measurements, time-correlated fluorescence, and flash photolysis. The dyes exhibit absorbance and fluorescence maxima in the near-IR (750-810 nm) with large $\varepsilon$ ($\sim$200,000 M$\sp{-1}$cm$\sp{-1})$ and $\Phi\sb{\rm f}\sim0.05$-0.15. Dyes …
Fluorescence Lifetime Discrimination Of Near-Infrared Dye-Labeled Oligonucleotide Fragments Separated By Capillary Gel Electrophoresis For Base-Calling Applications In Dna Sequencing., Benjamin Leighton Legendre Jr
Fluorescence Lifetime Discrimination Of Near-Infrared Dye-Labeled Oligonucleotide Fragments Separated By Capillary Gel Electrophoresis For Base-Calling Applications In Dna Sequencing., Benjamin Leighton Legendre Jr
LSU Historical Dissertations and Theses
The research presented in this dissertation involves the construction of a near-infrared time-correlated single photon counting system which utilizes a mode-locked Ti:sapphire or pulsed diode laser as the excitation source and single photon avalanche diode as the photodetector and the subsequent study of two simple algorithms, the Maximum Likelihood Estimator (MLE) and the Rapid Lifetime Determination (RLD) methods, for fluorescence lifetime determination. The purpose of this research is to aid in the development of a low cost, highly efficient, and high throughput device for DNA sequencing which utilizes near-IR fluorophores which have similar absorption and emission properties but possess unique …
Synthesis Of Monodisperse Poly(Gamma-Benzyl-Alpha,L-Glutamate) Oligomers And Their Star-Shaped Derivatives., Xiaolan Wang
Synthesis Of Monodisperse Poly(Gamma-Benzyl-Alpha,L-Glutamate) Oligomers And Their Star-Shaped Derivatives., Xiaolan Wang
LSU Historical Dissertations and Theses
Poly($\gamma$-benzyl-$\alpha$,L-glutamate), PBLG, is a widely studied example of polypeptides. The preparation of monodisperse samples of PBLG and PBLG oligomer is difficult to achieve. In this work we probe the possibility of preparation of PBLG oligomers by polymerization of L-glutamic acid N-carboxyanhydride (NCA) with different initiators such as primary amine, sterically hindered secondary amine, tertiary amine, and strong base. Information regarding molecular weight distribution of these oligomers was obtained by applying MALDI-TOF mass spectrometry and reversed phase HPLC. While some researchers reported that application of primary amine initiators or polar solvents such as DMF could improve the molecular weight distributions of …
A Search For Biologically Active Phytochemicals From Endemic Plants Of The Southeastern United States., Steven Lynn Robbs
A Search For Biologically Active Phytochemicals From Endemic Plants Of The Southeastern United States., Steven Lynn Robbs
LSU Historical Dissertations and Theses
In an investigation of allelopathy in the Florida scrub, bioassays with terpenes were performed against: Lactuca sativa, Rudbeckia hirta, Leptochloa dubia and Schizachyrium scoparium. Cineole was phytotoxic against Rudbeckia at 17 ppm and Lactuca at 165 ppm. (S)-camphor was phytotoxic to Rudbeckia at 1 ppm, Lactuca at 28 ppm, and Leptochloa and Schizachyrium at 134 ppm. (R)-Camphor, myrtenol and myrtenal were phytotoxic against Rudbeckia at concentrations of 28, 25 and 15 ppm respectively. Farnesol stimulated the germination of Schizachyrium at concentrations up to 50 ppm and at 100 ppm it reduced the radicle length of all test species. Geraniol stimulated …
I. Photophysics And Photochemistry Of Molybdenum-Oxo Complexes. Ii. Synthesis Of A Ferrocene-Based Monomer For Use In Ring-Opening Metathesis Polymerization., Ralph Isovitsch
LSU Historical Dissertations and Theses
The brick-red ferrocenophene 1,4-(3,3$\sp\prime$-bis(1,1-dimethylpentyl)-1,1$\sp\prime$-ferrocenediyl) -1,3-butadiene was prepared via a six-step synthetic route. It was isolated and characterized for use as a monomer in Ring Opening Metathesis Polymerization. Fluorescent molybdenum(V)-oxo complexes such as $\rm MoOCl\sb4(H\sb2O)\sp-$ undergo thermal and photochemical reactions with the series of phosphines $\rm PEt\sb2,\ PEt\sb3Ph,\ PEtPh\sb2$ and PPh$\sb3$ as oxygen atom acceptors. PEt$\sb3$ reacts spontaneously to form several products: $\rm (PPh\sb4)\lbrack MoCl\sb4(PEt\sb3)\sb2\rbrack,\ (PPh\sb4)\sb2\lbrack MoOCl\sb5\rbrack{\cdot}2CH\sb2Cl\sb2,$ and a maroon oil that contains $\rm OPEt\sb3,\ MoOCl\sb2(PEt\sb3)\sb3$ and $\rm MoCl\sb4(PEt\sb3)\sb2.$ Both $\rm (PPh\sb4)\lbrack MoCl\sb4(PEt\sb3)\sb2\rbrack$ and OPEt$\sb3$ are products of an oxygen atom transfer reaction. PEt$\sb2$Ph and PEtPh$\sb2$ also produce the corresponding phosphine …