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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.
21

Roles of graphite in the reduction of azo-aromatic compounds with elemental iron

Ye, Jianchang. January 2006 (has links)
Thesis (Ph.D.)--University of Delaware, 2006. / Principal faculty advisor: Pei C. Chiu, Dept. of Civil & Environmental Engineering. Includes bibliographical references.
22

Controlling peptide conformations : stabilizing helices /

Kneller, Mark Byron, January 1999 (has links)
Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (p. [117]-123).
23

Advances in ansa-chromocene and gallocene chemistry /

Perrotin, Philippe. January 1900 (has links)
Thesis (Ph. D., Chemistry)--University of Idaho, August 2007. / Major professor: Pamela J. Shapiro. Includes bibliographical references. Also available online (PDF file) by subscription or by purchasing the individual file.
24

The influence of sulphur on the color of azo dyes ...

Palmer, George David, January 1926 (has links)
Thesis (Ph. D.)--Johns Hopkins University, 1924.
25

The influence of sulphur on the color of azo dyes ...

Waldron, William Robert, January 1922 (has links)
Thesis (Ph. D.)--Johns Hopkins University, 1922. / Biography.
26

Scalable chemistry involving diazonium salts

Akwi, Faith Mary January 2016 (has links)
Herein an alternative approach aimed at reducing the cost of numbering up technique as a scale up strategy for chemical processes from the laboratory bench top to the industry is explored. The effect of increasing channel size on the reaction conversion of the synthesis of azo compounds is investigated. This was achieved via a systematic investigative understanding of the synthesis in microreactors where a proof of concept study was performed to determine the optimum reaction parameters in azo coupling reactions involving couplers with aminated or hydroxylated groups in Little Things Factory-MS microreactors (Channel diameter: 1.0 mm) It was found that at slightly alkaline conditions (pH 8.55) and at a temperature of 25 °C, excellent conversions were attained in the azo coupling reaction of the diazonium salt solution of 2,4-dimethylaniline to 2-naphthol. On the other hand, the azo coupling reaction of the diazonium salt solution of p-nitroaniline to diphenylamine was found to thrive at a pH of 5.71 and at a temperature of 25 °C. Using, these optimized reaction parameters, the in-situ and reactive quench of diazonium salts in LTF-MS microreactors was investigated where it was found that at a flow rate of 0.2 ml/min, 0.03 ml/min and 0.07 ml/min of diazotizable amine & HCl, sodium nitrite and coupler solutions respectively, a conversion of 98% is achieved in approximately 2.4 minutes. A library of azo compounds was thus generated under these reaction conditions from couplers with aminated or hydroxylated aromatic aromatic systems. The scaled up synthesis of these compounds in a homemade PTFE tubing (ID 1.5 mm) reactor system was thereafter investigated and comparable conversions were observed. Capitalizing on the benefits of a large surface area and the short molecular diffusion distances observed in microreactors, in-situ phase transfer catalyzed azo coupling reaction of diphenylamine to p-nitroaniline was also explored. In this investigation a rapid and easy optimization protocol that yielded a 99%, 22% and 33% conversion of diphenylamine, carbazole and triphenylamine respectively in approximately 2.4 minutes using Chemtrix microreactors was established. On increasing the microreactor channel internal diameter in the scaled up synthesis approach, it was found that a 0.5 mm increase in channel internal diameter does result in lower reaction conversions.
27

The attempted synthesis of precursors of tetraaryldiazoethanes

Smedberg, Ronald Theodore 01 January 1969 (has links)
This research involves the investigation of possible useful synthetic methods leading to tetraaryldiazoethanes of the type PhPhIPhIICC(N2)PHIII or their precursors. The synthesis of these compounds is of importance since the carbenoid and carbonium ion decomposition of these compounds to tetraaryldiazoethanes would give formation about the nature of these intermediates.
28

The reactions of some simple ester-substituted radicals in solution

Simmonds, Michelle January 1997 (has links)
No description available.
29

Ab initio molecular dynamics studies on thermal decomposition of Azomethane and fluxionality of IF₇, IOF₆⁻ and Te₇⁻.

January 2001 (has links)
Hon Wan Chee Nicole Wendy. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 85-87). / Abstracts in English and Chinese. / THESIS COMMITTEE --- p.ii / ABSTRACT (English version) --- p.iii / ABSTRACT (Chinese version) --- p.v / ACKNOWLEDGEMENTS --- p.vii / TABLE OF CONTENTS --- p.viii / LIST OF FIGURES --- p.x / LIST OF TABLES --- p.xiii / Chapter CHAPTER 1. --- General Introduction / Chapter Section 1.1 --- Introduction --- p.1 / Chapter Section 1.2 --- Electronic Structure Calculation --- p.2 / Chapter Section 1.3 --- Molecular Dynamics --- p.10 / Chapter CHAPTER 2. --- Ab Initio Molecular Dynamics Study on Thermal Dissociation of Azomethane / Chapter Section 2.1 --- Introduction / Chapter Section 2.2 --- Computational Method --- p.17 / Chapter Section 2.3 --- Results and Discussion --- p.21 / Chapter Section 2.4 --- Conclusion --- p.47 / Chapter CHAPTER 3. --- "Ab Initio Molecular Dynamics Study on Fluxionality of IF7, TeF7- and iof6-" / Chapter Section 3.1 --- Introduction --- p.49 / Chapter Section 3.2 --- Computational Method --- p.52 / Chapter Section 3.3 --- Analysis --- p.55 / Chapter Section 3.4 --- Results and Discussion --- p.56 / Chapter Section 3.5 --- Conclusion --- p.83 / REFERENCES --- p.85
30

A study of the degradation of some azo dyes in waste disposal systems.

Pratt, Harry Davis January 1968 (has links)
No description available.

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