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Synthesis and Structure of Polynitro- and Polymenthylpolycyclic "Cage" Monomers and Polymers

Description: The objective of this study was to synthesize and characterize new energetic polycyclic "cage" compounds. As part of a program involved in the synthesis of new polynitropolycyclic compounds, 2,6-dinitro-5-methoxy- 7-carbomethoxypentacyclo[5. 3 .0 . 0* • * . CP • i ° . 0* •8]decane has been synthesized. This is a model system which can be used to study (1) the effect of nitro substitution on the photolability of carbon-carbon double bonds and (2) to develop methods for avoiding Haller-Bauer clea… more
Date: May 1987
Creator: Jin, Pei-Wen
Item Type: Refine your search to only Thesis or Dissertation
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Intramolecular 2+2 Cycloadditions of Ketenes

Description: The objective of this study was to explore intramolecular ketene cycloadditions with the anticipated results of developing new synthetic methodology for the synthesis of polycyclic compounds difficult to obtain by other procedures. (o-Alkenylphenoxy)ketenes were initially selected for this study because these ketenes provided a favorable proximity for the intramolecular [2+2] cycloaddition reactions. The difunctional precursors, (o-alkenylphenoxy)- acetic acids, were readily prepared from o-alk… more
Date: December 1986
Creator: Giang, Yun-Seng F. (Yun-Seng Frank)
Item Type: Refine your search to only Thesis or Dissertation
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Manufacturer [Sic] of Densified-Refuse Derived Fuel (d-RDF) Pellets and Methods for the Determination of d-RDF Pellet Densities

Description: There are 150 million tons of Municipal Solid Waste (MSW) annually produced in the United States, which is approximately equivalent to 150 million barrels of oil. MSW production is inexhaustible, and is increasing on an annual per capita basis of approximately three per cent. After controlling the moisture and adding a binder, the combustible portion of MSW was converted to pellets. The objects of this project were to 1) evaluate the binder, 2) prepare the pellets, and 3) evaluate the pellets w… more
Date: December 1986
Creator: Attili, Bassam Saleem
Item Type: Refine your search to only Thesis or Dissertation
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Chromatographic and Spectroscopic Studies on Aquatic Fulvic Acid

Description: High Performance Liquid Chromatography (HPLC) was used to investigate the utility of this technique for the analytical and preparative separation of components of aquatic fulvic acids (FA). Three modes of HPLC namely adsorption, anion exchange and reversed phase were evaluated. Aquatic fulvic acids were either extracted from surface water and sediment samples collected from the Southwest of the U.S., or were provided in a high purity form from the USGS. On the adsorption mode, a major fraction… more
Date: August 1986
Creator: Chang, David Juan-Yuan
Item Type: Refine your search to only Thesis or Dissertation
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Silenes and Silenoids in the Chemistry of Cyclopentadienylsilanes

Description: Evidence is presented that apparent silene products obtained from the metalation of cyclopentadienyldimethyl - chlorosilane either with tert-butyl1ithium or with methylenetriphenylphosphorane actually arise from the metalated starting material, a silenoid, rather than from a silafulvene intermediate. Trimethylmethoxysi1ane is shown to be an effective trap for dimethylsilafulvene. A new dimethylsilafulvene precursor, bis(dimethylmethoxysi1yl) cyclopentadiene, which gives high yields of dimethyld… more
Date: August 1986
Creator: Rozell, James M. (James Morris)
Item Type: Refine your search to only Thesis or Dissertation
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Methods Development for Ion Chromatography

Description: Ion chromatography (IC) as developed by Small et. al. in 1975 has become an efficient and reliable analytical technique for simultaneous analysis of multiple ions in solution. The principle requirement prior to use the IC for an analysis is sample preparation; these include sample decomposition, solvent extraction, and trapping in case the target element is in the gas phase, etc. Solvent extractions for fluoride, chloride, sodium, ammonium, and potassium ions which are soluble in soils are desc… more
Date: May 1986
Creator: Supachai Maketon
Item Type: Refine your search to only Thesis or Dissertation
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The Nature of Intermediates Produced Through Ligand-Substitution Reactions of Octahedral Metal Carbonyls

Description: Pulsed laser time-resolved ligand-substitution photochemistry for (DTO)W(CO)4, (DTN)W(CO)4, and (NP)Mo(CO)4 (DTO = 2,2,7,7-tetramethyl-3,6-diathiaoctane; DTN = 2,2,8,8- tetramethyl-3,7-diathianonane; NP = l-diethylamino-2- diphenylphosphinoethane) proceeds via initial fission of the W-S and Mo-P bonds, affording Cs and C4v five-coordinate intermediates for DTN and NP but largely Cs for DTO. The rates of reaction of these intermediates, via chelate ring closure and competitive bimolecular intera… more
Date: May 1986
Creator: Mansour, Saber E. (Saber El-Sayed)
Item Type: Refine your search to only Thesis or Dissertation
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Catalytic Calcination of Calcium Carbonate

Description: The calcination of calcium carbonate in a cement or a lime kiln uses approximately two to four times the theoretical quantity of energy predicted from thermodynamic calculation depending upon the type of the kiln used (1.4 x 10^6 Btu/ton theoretical to 6 x 10^6 Btu/ton actual). The objective of this research was to attempt to reduce the energy required for the calcination by 1. decreasing the calcination temperature of calcium carbonate, and/or 2. increasing the rate of calcination at a specifi… more
Date: August 1985
Creator: Safa, Ali Ibrahim, 1953-
Item Type: Refine your search to only Thesis or Dissertation
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Isomerization Reactions in Organosilicon Chemistry

Description: Dimethylsilene, generated from the thermal gas phase reaction of 1,1-dimethyl-1-silacyclobutane, reacts with alkynes to produce silacyclobutenes or acyclic silanes. The temperature dependence of the product ratios have been determined and the relative reactivities of three different alkynes toward the 1,1-dimethylsilene has been determined. 1-Hydrido-1-methylsilene has been generated by gas phase thermal decomposition from three different precursors. Trapping studies with butadiene and trimethy… more
Date: August 1985
Creator: Kwak, Young-Woo
Item Type: Refine your search to only Thesis or Dissertation
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The Study of Low Temperature Silene Generation

Description: The reactions of tert-butyl-, sec-butyl-, and n-butyllithium with dimethylfluorovinylsilane include addition to the double bond to give both silene and silenoid intermediates, fluorine substitution, and a novel vinyl substitution. For the tert-butyllithium reaction, product stereochemistry and trapping experiments using both cyclopentadiene and methoxytrimethylsilane show that silenes are not formed in THF. In hexane about 67% of the 1,3-disilacyclobutanes obtained arise from silene dimerizatio… more
Date: August 1985
Creator: Cheng, Albert Home-Been
Item Type: Refine your search to only Thesis or Dissertation
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Synthetic Applications of Ketene Cycloadditions: Natural and Novel Pyrethroid Insecticides

Description: A new synthetic route to natural and novel pyrethroid acids was developed utilizing ketene cycloaddition which is a significant improvement over existing syntheses. The newly synthesized pyrethroid acids were converted to pyrethroid esters and used to study structure-activity relationships. The cycloaddition of dichloroketene with 2,5-dimethyl-2,4-hexadiene yields (2+2) cycloaddition products, 2,2-dichlorocyclobutanones. The reductive removal of one chlorine atom from these cycloaddition produc… more
Date: August 1985
Creator: Ko, Jinren
Item Type: Refine your search to only Thesis or Dissertation
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Molecular Dynamics and Interactions in Liquids

Description: Various modern spectroscopies have been utilized with considerable success in recent years to probe the dynamics of vibrational and reorientational relaxation of molecules in condensed phases. We have studied the temperature dependence of the polarized and depolarized Raman spectra of various modes in the following dihalomethanes: dibromomethane, dichloromethane, dichloromethane-d2, and bromochloromethane. Among other observed trends, we have found the following: Vibrational dephasing times cal… more
Date: May 1985
Creator: Chen, Jen Hui
Item Type: Refine your search to only Thesis or Dissertation
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Calcium Aluminates Synthesis, Characterization, and Hydration Behavior

Description: The hydration behavior of the calcium aluminates as a function of the glass content, the curing temperature, and the water-solid ratio was investigated. In order to keep them from influencing the results, the free-lime content and the surface area of all samples were kept constant, whenever possible. Samples were hydrated with a water-solid ratio of 10/1 for periods of 1 to 90 days. Three curing temperatures were studied; 2°C, 25°C, and 50°C. Samples were hydrated in tightly sealed polyethylene… more
Date: December 1984
Creator: Griffin, Joseph George
Item Type: Refine your search to only Thesis or Dissertation
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Studies on Human Plasma Lecithin:Cholesterol Acyltransferase: Physical and Chemical Characterization and Coupled Spectrophotometric Enzyme Assay

Description: The physico-chemical properties of lecithin:cholesterol acyltransferase were investigated. The amino acid composition analysis showed a relatively high content of glutamic acid, aspartic acid, glycine and leucine. The spectrophotometric titration of phenolic groups in the enzyme showed a large increase in absorbance at 295 nm with an apparent pK of about 12.0. The largest change in molar ellipticity at 222 nm was also observed above pH 11. Circular dichroism studies revealed that human lecithin… more
Date: December 1984
Creator: Hara, Shinichi
Item Type: Refine your search to only Thesis or Dissertation
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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
Item Type: Refine your search to only Thesis or Dissertation
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Synthesis and Characterization of Copper(II) Complexes

Description: A series of dihydroxy bridged copper(II) complexes of the type [(L)Cu(OH)₂Cu(L)]x₂ * nH₂0, where L is 2,2'-bipyridine, 4,4'-dimethyl-2,2'-bipyridine or 1,10-phenanthroline, x is a counter ion, and n is the number of water molecules, was synthesized. In the case of monohydroxy bridged copper(II) complexes, we have found a new method of synthesis for [ (L)₂Cu(OH)Cu(L)₂ ] (ClO₄)₃, where L is 2,2'-bipyridine or 1,10-phenanthroline. We have synthesized five new monohydroxy bridged copper(II) complex… more
Date: December 1984
Creator: Amani, Saeid
Item Type: Refine your search to only Thesis or Dissertation
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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
Item Type: Refine your search to only Thesis or Dissertation
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Silene Stereochemistry

Description: The reaction of tert-butyllithium with chloromethylphenylvinylsilane at low temperatures in hexane gave a 48% yield of a mixture of the five isomers of 1,3-dimethyl-1,3-diphenyl-2,4-dineopentyl-1,3-disilacyclobutane, formed by the head-to-tail dimerization of both E- and Z-1-methyl-1-phenyl-2-neopentylsilenes, along with an acyclic dimer. These were separated and their stereochemistry was established by ('1)H- and ('13)C-NMR spectroscopy. The E- and Z-silenes were also trapped as their {4 + 2} … more
Date: August 1984
Creator: Lee, Myong Euy
Item Type: Refine your search to only Thesis or Dissertation
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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
Item Type: Refine your search to only Thesis or Dissertation
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Synthetic Applications of Ketene Cycloadditions Lactams and Coumarins

Description: The objective of this study was to develop new synthetical routes to natural and industrial products utilizing ketene cycioaddition reactions. The cycioaddition of diphenylketene with α,β-unsaturated imines yields (2+2) cycioaddition products, g-lactams. However, electron donating groups, such as dimethylamine, in the 4-position of the α,β-unsaturated imines result in (4+2) cycloaddition products, ∂-lactams. Dichloroketene reacted with α,β-unsaturated imines to yield (4+2) cycloaddition product… more
Date: August 1984
Creator: Shieh, Chia Hui
Item Type: Refine your search to only Thesis or Dissertation
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Isolation and Partial Characterization of Lecithin Cholesterol Acyltransferase and High Density Lipoprotein from Hog Plasma

Description: Lecithin:cholesterol acyltransferase (LCAT) was purified 30,000-fold from hog plasma in a homogeneous state as indicated by polyacrylamide gel electrophoresis. The purified enzyme had an apparent molecular weight of 66,000 and was found to contain about 21.4 percent (w/w) carbohydrate. The properties of hog LCAT including amino acid composition were compared with human LCAT. High density lipoprotein (HDL) was isolated from the hog plasma by an immunoaffinity column chromatography. The isolated … more
Date: May 1984
Creator: Park, Yong Bok
Item Type: Refine your search to only Thesis or Dissertation
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Raman Studies of Molecular Dynamics and Interactions in Liquids

Description: In order to explore the N-H stretching region of aliphatic amines, we performed a study of the Raman spectrum of n-propylamine at various concentrations in cyclohexane. Statistical analysis provided evidence of a second symmetric stretching vibration, which we were able to assign to nonhydrogen bonded NH2 groups. To obtain additional evidence on the existence of monomers in n-propylamine and to further study hydrogen bonding and Fermi resonance in aliphatic amines, we extended the investigation… more
Date: May 1984
Creator: Friedman, Barry R. (Barry Richard)
Item Type: Refine your search to only Thesis or Dissertation
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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.
Item Type: Refine your search to only Thesis or Dissertation
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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)
Item Type: Refine your search to only Thesis or Dissertation
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