UNT Theses and Dissertations - 7 Matching Results

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Experimental and Theoretical Studies of Polycarbocyclic Compounds

Description: Part I. Diels-Alder cycloadditions of 1,2,3,4,9,9-hexachloro-1α,4α,4aα,8aβ-tetrahydro-l,4-methanonaphthalene (32) and 1,2,3,4,9,9-hexachloro-lα,4α,6,7- tetrahydro-l,4-methanonaphthalene (33) to 4-methyl- and 4-phenyl-l,2,4-triazoline-3,5-dione [MTAD and PTAD, respectively] and to N-methylmaleimide (NMM) have been studied. The structures of several of the resulting cycloadducts were determined by X-ray crystallographic methods. The observed stereoselectivity of each of these Diels-Alder reaction… more
Date: May 1998
Creator: Shukla, Rajesh, 1964-
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Interactions of Clean and Sulfur-modified Reactive Metal Surfaces with Aqueous Vapor and Liquid Environments : A Combined Ultra-high Vacuum/electrochemistry Study

Description: The focus of this research is to explore the molecular-level interactions between reactive metal surfaces and aqueous environments by combined ultra-high vacuum/electrochemistry (UHV-EC) methodology. The objectives of this work are to understand (1) the effects of sulfate ions on the passivity of metal oxide/hydroxide surface layer, (2) the effects of sulfur-modification on the evolution of metal oxide/hydroxide surface layer, and (3) the effects of sulfur adsorbate on cation adsorption at meta… more
Date: May 1998
Creator: Lin, Tien-Chih, 1966-
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Kinetics and Mechanisms of Metal Carbonyls

Description: Pulsed laser flash photolysis with both visible and infrared detection has been applied to the study of the displacement of weakly coordinating ligands (Lw) by strongly "trapping" nucleophiles (Ls) containing either an olefinic functionality (Ls = 1-hexene, 1-decene, 1-tetradecene) or nitrogen (Ls = acetonitrile, hydrocinnamonitrile) from the photogenerated 16 electron pentacarbonylchromium (0) intermediate. 5-Chloropent-l-ene (Cl-ol), a potentially bidentate ligand, has been shown to form (ol-… more
Date: May 1998
Creator: Ladogana, Santino
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Part I: Solid State Studies of Larger Calixarenes : Part II: Synthesis and Characterization of Metallocalixarenes

Description: Calixarenes are a class of macrocyclic compounds that have garnered interest in large part because of their ability to form host-guest complexes with various types of molecules. For all of the studies of complex formation by calixarenes, most of the work to date has concentrated upon the smaller calixarenes, and little is understood about the relationship between the complexes formed when in solution and that observed in the solid state. The first part of the study, presented in Chapter 3, is o… more
Date: May 1998
Creator: Smith, Janna Marie
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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A Quenchofluorometric Study of Polycyclic Aromatic Hydrocarbons in Molecularly Organized Media

Description: Detection, identification and separation of polycyclic aromatic compounds in environmental samples are of extreme importance since many of these compounds are well known for their potential carcinogenic and/or mutagenic activities. Selective quenching of molecular fluorescence can be utilized effectively to analyze mixtures containing different polycyclic aromatic hydrocarbons. Molecularly organized assemblies are used widely in detection and separation of these compounds mainly because of less… more
Date: May 1998
Creator: Pandey, Siddharth
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Stoichiometry and Deposition Temperature Dependence of the Microstructural and Electrical Properties of Barium Strontium Titanate Thin Films

Description: Barium Strontium Titanate (BST) was deposited on Pt/ZrO2 / SiO2/Si substrates using liquid source metal organic chemical vapor deposition. A stoichiometry series was deposited with various GrII/Ti ratios (0.658 to 1.022) and a temperature series was deposited at 550 to 700°C. The thin films were characterized using transmission electron microscopy. Both series of samples contained cubic perovskite BST and an amorphous phase. The grain size increased and the volume fraction of amorphous phase de… more
Date: May 1998
Creator: Pena, Piedad
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Thermodynamic and Structural Studies of Layered Double Hydroxides

Description: The preparation of layered double hydroxides via titration with sodium hydroxide was thoroughly investigated for a number of M(II)/M(III) combinations. These titration curves were examined and used to calculate nominal solubility product constants and other thermodynamic quantities for the various LDH chloride systems.
Date: May 1998
Creator: Boclair, Joseph W. (Joseph Walter)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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