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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Approaches to the synthesis of highly strained polycyclic hydrocarbons via bistosylhydrazones

Druelinger, Melvin L. January 1967 (has links)
Thesis (Ph. D.)--University of Wisconsin, 1967. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.
32

Degradation of polycyclic aromatic hydrocarbons by actinomycetes /

Pizzul, Leticia. January 2006 (has links)
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2006. / Thesis documentation sheet inserted. Appendix reprints four papers and manuscripts co-authored with others. Includes bibliographical references. Also partially issued electronically via World Wide Web in PDF format; online version lacks appendix.
33

The effect of sampling procedures on organic aerosol measurement /

McDow, Stephen Robert. January 1986 (has links)
Thesis (Ph. D.)--Oregon Graduate Center, 1986.
34

New Chiral Aromatic Architectures

January 2016 (has links)
acase@tulane.edu / The syntheses and structural characterization of 3-arylimino steroids, tribenzodecacyclene, hexabenzodecacyclene, and a new class of twisted chiral polycyclic aromatic compounds, the “hairpin furans” are described. In the hope of generating a new class of materials with large optical rotations, various arylamines were condensed with cholest-4-ene-3,6-dione (14) to give 3-arylimino steroids. These compounds possess moderately high specific rotations ([α]D ~ 300-800) and strong circular dichroism. One such derivative, 3-(4-methoxyphenylimino)cholest-4- en-6-one (15), crystallizes as the (E)-imine and upon dissolution undergoes mutarotation to an equilibrium mixture of (E)- and (Z)-isomers with a half-life of approximately 1 h at room temperature, as judged by both NMR spectroscopy and polarimetry. High-temperature, TiCl4-catalyzed, triple aldol condensations of aceanthrenone 26 and acenaphthacenone 27 gave tribenzodecacyclene 18 and hexabenzodecacyclene 19, respectively, in yields of 16% and 0.8%, respectively. Compound 18 is a red, crystalline solid that is stable under ordinary conditions; its X-ray structure reveals it to be a strongly pitched, C3-symmetric, molecular propeller. In contrast, the more highly strained compound 19 is a blue-black solid whose solutions are unstable to air and light. Its simple NMR spectra, as well as HDFT calculations, indicated that it is a D3-symmetric molecular propeller. The thermal reaction of two cyclopentadienones with 5,5’-binaphthoquinone or 6,6’-dimethoxy-5,5’-binaphthoquinone in refluxing nitrobenzene (210 °C) gives, in a single synthetic step that includes two Diels-Alder additions, two decarbonylations, and two dehydrogenations, giant biaryl bisquinones (compounds 42, 50, 52, 53 and 62). However, when two cyclopentadienones react with 6,6’-dimethoxy-5,5’- binaphthoquinone in nitrobenzene at higher temperatures (250-260 °C), the resulting products are molecular ribbons composed of two twisted aromatic systems fused to a heteropentahelicene (49, 51, and 54). These molecules are representatives of a new class of chiral polycyclic aromatic compounds, the “hairpin furans”. Interestingly, reheating a dimethoxy-substituted giant biaryl (e.g., 52) in nitrobenzene at 260 °C does not yield the corresponding hairpin furan, and the mechanistic studies indicate that some intermediate or byproduct of the synthesis of the giant biaryls is a reagent or catalyst necessary for the conversion of the dimethoxybiaryl to the furan. / 1 / Xin Geng
35

Thermal and photo-induced interconversions of polycyclic hydrocarbons /

Kukla, Michael Joseph January 1974 (has links)
No description available.
36

Syntheses of Highly Strained Energetic Molecules and Development of New Synthetic Methodology

Wu, An-hsiang 05 1900 (has links)
The objective of this study was to synthesize new energetic, strained, saturated polycyclic compounds. For this purpose, new methodology has been developed, as follows: (i) Ketenes have been generated in situ via treatment of aldo-, keto- or alkenoic acid with either toluenesulfonyl chloride or 2-chloro-1-methylpyridfniurn iodide (Mulkaiyama's reagent). The reactive intermediates thereby generated have been found to undergo intramolecular [2+2] cycloaddition reactions in these systems.
37

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

Huang, Chunmin 08 1900 (has links)
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 intermediates for the synthesis of new, substituted tricyclopentanoid natural products (triquinanes) and related systems. Compounds 1-4 were identified as target molecules in this connection.
38

Modulation of aryl hydrocarbon receptor (AhR) activity by flavonoids.

January 2011 (has links)
Poon, Ching Ho. / "October 2010." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 95-102). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.3 / TABLE OF CONTENTS --- p.4 / ABSTRACT --- p.6 / 摘要 --- p.8 / ABBREVIATIONS --- p.10 / LIST OF FIGURES --- p.11 / Chapter CHAPTER 1 --- GENERAL INTRODUCTION --- p.14 / Chapter CHAPTER 2 --- MATERIALS AND METHODS --- p.26 / Chemicals and materials --- p.26 / Mammalian cell culture --- p.27 / Reporter gene assay --- p.28 / Semi-quantitative real-time PCR --- p.30 / RNA degradation assay --- p.31 / Western Blotting --- p.32 / Electrophoretic mobility shift assay (EMSA) --- p.34 / EROD assay in intact cells --- p.35 / Statistical Analysis --- p.35 / Chapter CHAPTER 3 --- Two citrus bioflavonoids suppress DMBA-induced CYP1 gene expression and activity via antagonizing AhR transactivation activity --- p.36 / Chapter CHAPTER 4 --- Modulation of AhR-mediated CYP1 enzymes transcription by licorice flavonoids isoliquiritigenin --- p.60 / Chapter CHAPTER 5 --- Protein kinase signaling pathways are not involved in the modulation of AhR transactivation activity by flavonoids --- p.81 / Chapter CHAPTER 6 --- SUMMARY --- p.94 / BIBLIOGRAPHY --- p.97
39

Beyond the 16 EPA priority pollutant PAHs : environmental characterizations of oxygenated PAHs and dibenzopyrene isomers /

Layshock, Julie. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 104-108). Also available on the World Wide Web.
40

Synthesis of hyperbranched polyarylenes and poly(aroylarylene)s by polycyclotrimerization of alkynes and their applications as photoresist and precursors for magnetic ceramics /

Dong, Hongchen. January 2005 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references. Also available in electronic version.

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