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Synthesis of Aziridine Analogues of Pyrethroids

Description: Rules which correlate structure and insecticidal activity of pyrethroids have evolved over the last thirty years from the results obtained in the testing of various synthetic pyrethroids. The major portion of these rules have dealt either with the development of new alcohol moieties or variations in the unsaturated side chain of the cyclopropane ring. There has been very little work done concerning modifications of the cyclopropane ring. This study was initiated to discover the affect of substi… more
Date: May 1981
Creator: Sheppard, Rex Gerald
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Mass Spectral Study of Trimethylsilylmethyl Substituted Chlorosilanes

Description: The mass spectra of the compounds [Me 3 SiCH2 nSiCl 4 n (n=1-3) were studied in detail. MIKES and CID spectra were used in conjunction with the observance of metastable processes to develop consistent fragmentation schemes. Particular attention is drawn to the formation of charged and neutral species containing the silicon-carbon double bond, including 2-silaallene, under conditions of electron impact.
Date: December 1982
Creator: Pope, Keith Randal
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Brainstem Lipids' Relationship to Death

Description: Previous work relating postmortem findings with cause of death have focused on the vitreous portion of the body. This research investigated the link between phospholipids in the brainstem and cause of death. The lipids were extracted by the Folch extraction method and then separated by High Performance Thin Layer Chromatography. These techniques gave excellent separation and resolution. Results showed no link between cause of death and the type of lipids found in the brainstem after death.
Date: December 1982
Creator: Schrynemeeckers, Patrick J.
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Hydraulic Activity in Synthetic and Commercial Slags

Description: Slag, by itself, shows very little hydraulic activity. However, hydration is greatly accelerated by incorporation of the slag with Portland cement. This phenomenon is due to the activating role of calcium hydroxide released from the hydration of Portland cement. This study was aimed at finding other activators that will increase hydration in both synthetic and commercial slags. The effects of chemical composition and the aggregation state of the slag on the hydration process were also investiga… more
Date: May 1982
Creator: Saad, Bahruddin bin
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Investigation of Substituent Effects of 2-Substituted Silaethylenes

Description: This investigation is concerned with determining whether a carbon substituent or a silicon substituent on the carbon terminus of a silicon-carbon double bond has a more stabilizing effect. Two different 2-substituted silaethylenes were generated at the same time by pyrolyzing 1, 1-dimethyl-2-neopentyl-4- (dimethylalkoxysilyl) silacyclobutanes in a nitrogen flow system. The results of these pyrolyses, both neat and in the presence of a trapping reagent, show that the silaethylene with a silicon … more
Date: December 1980
Creator: Snyder, Walter David
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Determination of Halogens in Organic Compounds by Using Sodium Fusion-Ion Chromatography Method

Description: A sodium fusion-Ion chromatographic method for determination of fluorine, chlorine, bromine, and iodine in organic compounds is described. Seventeen organic halogen compounds and eleven mixtures were decomposed by Na fumes at 280-290°C for one hour or longer. The absorbing solutions were injected for ion chromatographic analysis using electrochemical and conductometric detectors. The arrangement of the apparatus includes the placement of the electrochemical and conductometric detectors. This me… more
Date: August 1983
Creator: Wang, Chung-Yu
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The Regulation of HMG-CoA Reductase by Enzyme-Lipid Interactions

Description: The temperature-dependent catalytic activity of rat liver 3-hydroxy-3 -methylglutaryl coenzyme A reductase (HMG-CoA reductase) displays the nonlinear Arrhenius behavior characteristic of many membrane-bound enzymes. A two-conformer equilibrium model has been developed to characterize this behavior. In the model, HMG-CoA reductase undergoes a conformational change from a low specific activity to a high specific activity form. This conformation change is apparently driven by a temperature-depende… more
Date: May 1981
Creator: Smith, Vana L.
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Raman Studies of Conformational Energies and Hydrogen Bonding in Alcohols

Description: The conformational energy differences have been determined for ethylene glycol, 2- chloroethanol, and 2,2- dichloroethanol in the neat liquid, DMSO, and H20 with Raman spectroscopy. Spectra in the 0-H valence region were utilized to determine the energy difference between interand intramolecularly hydrogen bonded species. It was found that the solvent effect on the relative stabilities of the gauche and trans rotamers of the alcohols differ significantly. The results also indicate that, unlike … more
Date: August 1982
Creator: Maleknia, Simindokht
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Studies on the Biological Activity of N-nitrosamines

Description: Two aspects of the biological activity of N-nitrosamines were studied. First, the effect of ascorbate on the mutagenicity of N-nitrosopiperidines was studied in the Ames Salmanella/ mammalian microsome mutagenicity test. The addition of ascorbate significantly enhanced the mutagenicity of these compounds. This enhancement was selective for N-nitrosamines suggesting a possible role of ascorbate in N-nitrosamine induced carcinogenicity. Second, the technique of velocity sedimentation in alkaline … more
Date: August 1980
Creator: Barton, Rodney A. (Rodney Alan)
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Reactivity of Five-Coordinate Intermediates Derived from (Chelate) Tetracarbonylmetal (0) Complexes

Description: The reactivity of the [(Phen)Cr(CO)_3] intermediate with phosphines and phosphites (L) has been investigated through ligand-competition studies. This intermediate possesses virtually no ability to discriminate among L. The agreement between reactivity data for the thermal and photochemically-generated intermediates indicates that the same intermediate is produced via each process. Pulsed laser flash photolysis of (n^2-NP)M(CO)_4 (I) (M = Cr, Mo; NP = 1-diethylamino-2-diphenylphosphinoethane) in… more
Date: December 1983
Creator: Mansour, Saber E. (Saber El-Sayed)
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Conformation-Activity Studies of Pyrethroid Alcohols

Description: The synthesis and insecticidal activity of certain alcohols (hydroxymethyldibenzofurans, hydroxymethyldibenzothiophenes and some of their ⍺-cyano derivatives), esterified with trans-chrysanthemic acid, were investigated. The preparation of these planar alcohol moieties was undertaken to study conformation-activity effects in insecticides of the pyrethroid type. The synthesis of final ester products employed two methods. One was the direct condensation of the appropriate alcohol with chrysanthem… more
Date: August 1984
Creator: Tu, Huai-Tsu
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The Analysis of Fire Debris Using Nuclear Magnetic Resonance Spectroscopy

Description: This paper describes a new technique for analyzing fire debris using nuclear magnetic resonance (NMR) spectroscopy. Petroleum distillates, which are commonly used accelerants, were weathered, burned, and steamdistilled. These, as well as virgin samples of the accelerants, were analyzed by gas chromatography and nuclear magnetic resonance spectroscopy. In addition, solvent studies and detectibility limit studies were conducted. The use of NMR is described as a valuable adjunct to the existing me… more
Date: August 1981
Creator: Bryce, Kenneth L.
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Synthesis and Insecticidal Activity of Gem-Cyano Pyrethroids

Description: The synthesis and insecticidal activity of a series of 2,2-dicyano cyclopropane carboxylic acids, (3-phenoxyphenyl)- methyl esters were investigated. Synthesis of the compounds was accomplished by reaction of a dimethyl sulfonium carbethoxy ylide with propanedinitrile alkylidene compounds. Final products were formed in one step by use of the (3-phenoxyphenyl)-methyl ester of the ylide. Insecticidal activity was determined at 500 ppm application with Permethrin as the standard against houseflies… more
Date: August 1980
Creator: Wilkerson, Michael G.
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Kinetic Study of Ligand Exchange in mu-(2,2,8,8-Tetramethyl-3,7- Dithianonane)-Decacarbonylditungsten(0)

Description: The substitution reaction of (DTN)W2 (CO)10 with P(OCH(CH3 )2 )3 is a stepwise reaction. The kinetics of step 1 follow the equation: -d[substrate] /dt = kld [substrate] + k la [substrate] [ligand]. Thus the mechanism of step 1 is expected to be a competition between dissociative and associative pathways. The kinetics of step 2 follow the equation: -d[(DTN)W(CO)5]/dt = k2dk3[(DTN)W(CO)5][ligand]/k-2[DTN] + k3[ligand] The plot of kobsd versus [ligand] thus is a hyperbolic curve and the plot of 1… more
Date: May 1982
Creator: Yang, Sang-Nin
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Syntheses of a New C₂₂H₂₈ Cage Hydrocarbon System and 2,2- Tetramethylene-1 /4-Dibromobutane

Description: (1). An improved method for synthesizing bicyclo (2,2,1) hepta-2,5-diene-7-spiro-1'-cyclopentane (5) has been developed. Thermal reaction of compound (5) with neat iron pentacarbonyl under nitrogen atmosphere affords the corresponding cage dimer (6). Some aspects of the syntheses, spectra, and chemistry of compound (5) and (6) are discussed. (2). A structure isomer of decamethyldodecahedrane (C₃₀H₄₀), molecule (11), is expected to be synthesized via thermal reaction of iron carbonyl complexes w… more
Date: December 1984
Creator: Wu, An-hsiang
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The Effect of Ozonation in Reducing Trihalomethane Formation Potential

Description: Trihalomethanes such as chloroform, dichlorobromomethane, dibromochloromethane, and bromoform are formed when natural water is chlorinated in water treatment. This investigation explores the use of ozone to remove organic precursors from natural water, thus decreasing trihalomethane formation potential. The data suggest a mechanism involving formation of secondary precursors after prolonged contact with ozone, suggesting that trihalomethane precursors may be minimized by using low doses of ozon… more
Date: May 1981
Creator: Lin, Simon H.
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Synthesis of trimethylsilyl-substituted pentacyclo(5.4.0.0²,⁶.0³,¹º.0⁵,⁹)undecanes and chloro-substituted pentacyclo(5.4.0.0²,⁶.0³,¹º.0⁵,⁹)undecane

Description: As part of a continuing study of the synthesis and chemistry of new, substituted pentacyclo(5.4.0.0²,⁶.0³,¹º.0⁵,⁹)undecanes, the following compounds have been synthesized: 1: X=O, Y=SiMe_3; 2: X=CH_2, Y=SiMe_3; 3: X=O, Y=Cl; 6: X=OAc, Y=H; 8: X=OC(O)Ph, Y=H; 9: X=OSO_2Ph, Y=H; 11: X=OH, Y=H; 12: X=OMe, Y=H; 14: X=CHSiMe_3, Y=SiMe_3; 15: X=OH, Y=Cl; 16: X=OAc, Y=Cl; 17: X=OMe, Y=Cl. An important objective of this work is to prepare new polycyclic cage compounds which can be utilized as intermedi… more
Date: August 1984
Creator: Huang, Chunmin
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A Carbon-13 and Lithium-6 NMR Study of Alkyllithium Compounds

Description: A variable temperature 13C and 6Li NMR study has been conducted for 6Li-enriched ethyl-, n-propyl-, isopropyl-, n-butyl-, isobutyl-, t-butyl--, isopentyl-, 2-ethylbutyl-, and n-hexyllithium in cyclopentane. Significant differences in the 13C NMR parameters are observed as a function of the alkyl group and temperature. These changes are compared to the 6Li spectra and explained in terms of the aggregates present. 13C-6Li coupling is readily observed in both the 13 6 C and Li spectra of compounds… more
Date: December 1983
Creator: Jensen, Randy M.
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Vibrational Dephasing of Haloalkanes and Halobenzenes

Description: The Raman linewidths of the carbon-halogen stretching mode was measured as a function of temperature in ethyl bromide, isopropyl chloride, isopropyl bromide, t-butyl chloride, t-butyl bromide, chlorobenzene, bromobenzene, iodobenzene and o-dichlorobenzene. The vibrational relaxation times showed a very clear trend. Together with earlier work on methyl iodide, these results provide evidence that the vibrational dephasing efficiencies (T^-1_iso) of the carbon-halogen mode vary in the order of Cl … more
Date: May 1983
Creator: Ho, Salina Yuen-Han
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Studies on Lipoprotein Specificity of Human Plasma Lecithin Cholesterol Acyltransferase

Description: Huian plasma high-density lipoprotein (HDL) were isolated by a procedure employing polyanion precipitation and column chromatography. Lipid and protein composition of the HDL isolated by this method was found to be similar to another HDL preparation isolated by ultracentrifugation. However, minor differences were noted, including a higher phospholipid and apoproteinE content and lower triglyceride content of the HDL isolated by column chromatography. Four subfraction of HDL were obtained follow… more
Date: May 1981
Creator: Jahani, Mehrnoosh
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Isolation and Characterization of Two Enzyme Proteins Catalyzing Oxido-Reduction at C-9 and C-15 of Prostaglandins from Swine Kidney

Description: Two swine kidney proteins (PI 4.8 and 5.8) both possessing 9-prostaglandin ketoreductase (9-PGKR) and 15-hydroxyprostaglandin dehydrogenase (15-PGDH) activities were purified to homogeneity. Purification increased specific activities in parallel. Molecular weight, subunit size, amino acid composition, coenzyme and substrate specificity and antigenicity of both proteins were similar. Gel filtration and SDS-polyacrylamide gel electrophoresis molecular weights of 29,500 and 29,000, respectively, s… more
Date: December 1980
Creator: Chang, David Guey-Bin
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Simultaneous Part-Per-Billion Determination of Sodium and Chloride Ions

Description: The method utilizes both cation and anion concentrator columns in parallel as a preconcentration system. The preconcentrator system is loaded using a reagent delivery module operated for a specific time at a preset flow rate. Total injection volumes of 2-5 ml are routinely used. Various chromatograms are discussed along with detailed information concerning detection limits for sodium and chloride, the system operating conditions, and the solutions to other pitfalls which have arisen during the … more
Date: August 1987
Creator: Gan, Din-Chung
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Optimization of High Performance Liquid Chromatographic Separations

Description: This study had a twofold purpose. First, the usefulness of the simplex algorithm as a short method of optimization in high performance liquid chromatographic separations was investigated. The second was to test a modified simplex method. The volume fractions of mobile phase components were chosen as the variable factors in the optimization process. Four test cases were performed which included separation of cholesterol esters, naphthalene and its derivatives, polycyclic aromatic compounds, and … more
Date: August 1983
Creator: Nguyen, Khanh Thi
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Purification and Studies of Methylglyoxal Reductase from Sheep Liver

Description: The objectives of these investigations were (1) the purification of MG reductase from sheep liver and (2) studies of some of its characteristics. MG reductase was purified 40 fold and showed a single band on SDS-PAGE. Molecular weight estimations with SDS-PAGE showed a molecular weight of 44,000; although gel filtration with Sephadex G-150 gave a molecular weight of 87,000 indicating that the enzyme might be a dimer. The Km for MG is 1.42 mM and for NADH it is 0.04 mM. The pH optimum for the pu… more
Date: May 1983
Creator: Lambert, Patricia A.
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