UNT Theses and Dissertations - 10 Matching Results

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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
Partner: UNT Libraries
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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
Partner: UNT Libraries
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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
Partner: UNT Libraries
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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
Partner: UNT Libraries
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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
Partner: UNT Libraries
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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
Partner: UNT Libraries
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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
Partner: UNT Libraries
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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
Partner: UNT Libraries
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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
Partner: UNT Libraries
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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
Partner: UNT Libraries
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