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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.
71

Five-membered sulfur-nitrogen ring compounds /

Matuska, Vit. January 2009 (has links)
Thesis (Ph.D.) - University of St Andrews, August 2009. / Restricted until 18th August 2010.
72

The vibrational spectrum of some compounds of sulfur and nitrogen

Bragin, Joseph, 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.
73

The synthesis and structural characterization of main group and transition metal complexes supported by nitrogen based ligands

Lesikar, Leslie Anne. January 2008 (has links) (PDF)
Thesis (Ph.D.)--Texas Christian University, 2008. / Title from dissertation title page (viewed Feb. 26, 2009). Includes abstract. Includes bibliographical references.
74

Rh(III)-Catalyzed Alkene Difunctionalization for the Synthesis of Nitrogen-Containing Compounds

Lee, Sumin January 2021 (has links)
Nitrogen-containing compounds are essential structural units in a myriad of biologically active molecules including pharmaceuticals. Although numerous synthetic methods have been developed over the last few decades, new methods constructing them in an efficient way from readily accessible starting material are still great of interest. As a coupling partner of the reaction, alkenes are abundant, general, and therefore ideal starting materials to synthesize a variety of complex, value-added products. In this thesis, we have utilized Rh(III) catalysis to develop efficient synthetic methodologies for nitrogen-containing compounds using alkenes as coupling partners. In Chapter 2, we developed a unique disconnection approach to pyrrolidines using a-olefins as a 4-carbon source and hydroxylamine derivatives as a nitrogen source of the reaction. In Chapter 3, regio- and diastereoselective synthesis of a,b-unsaturated-d-lactams from acrylamide and unactivated alkenes initiated from C-H activation are discussed. In Chapters 4 and 5, three-component alkene difunctionalization of alkenes delivering acyclic aminated products including a-amino acids are described.
75

Effect of hydrogen sulfide on the kinetics of hydrodenitrogenation of quinoline and its reaction intermediates in vapor phase

Gültekin, Selâhattin. January 1980 (has links)
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemical Engineering, 1980 / Vita. / Bibliography: leaves 269-273. / by Selahattin Gültekin. / Ph. D. / Ph. D. Massachusetts Institute of Technology, Department of Chemical Engineering
76

The Determination of Nitrogen-Containing Compounds in Heavy Syncrude Oils

Fung, Richard L. C. 02 1900 (has links)
<p> A two stage chromatographic separation method was adapted to the separation of nitrogen-containing compounds from heavy syncrude oils. Crude oil samples were first chromatographed on alumina to obtain an aliphatic fraction A1 (70 wt% of oil, <1% of total nitrogen), a polycyclic aromatic hydrocarbon fraction A2 (20%, 16%N) and a nitrogenous fraction A3 (3%, 80%N). The nitrogenous fraction was further separated on silicic acid into three fractions: a secondary-PANH fraction S1 (61% total N), an amino-PAH and tertiary-PANH fraction S2 (4%N) and a tertiary-PANH fraction S3 (9%N). One Tar Sand and two oil residue samples, provided by Shell Canada Ltd, were taken through this procedure.</p> <p> The nitrogen-containing fractions were analyzed by mass spectrometry (electron impact, methane chemical ionization and ammonia chemical ionization) and by two chromatographic methods (gas and reverse phase liquid chromatography). Further analyses were performed using gas chromatography/mass spectrometry, liquid chromatography/mass spectrometry and nuclear magnetic resonance (1H and 13C) spectroscopy.</p> <p> The nitrogenous components in the S1 fractions were shown to be alkylated carbazoles, containing from one to twenty carbons attached to the carbazole nucleus, in varying degrees of unsaturation ranging from zero to five degrees of unsaturation. The distribution of carbon substitution maximized in the C5 to C8 range for the different series of alkylcarbazoles. The distribution of the degrees of unsaturation in the Tar Sand oil sample was: saturated carbazoles, 32%, 1-degree unsaturates, 23%, 2-degree, 9%, 3-degree, 16%, 4-degree, 12% and 5-degree, 8%. In the processed Peace River residue, the ratio between the saturated, 1-, 2-, 3-, 4- and 5-degree unsaturated carbazoles was 28%:39%:18%:6%:6%:3%. From the 1H NMR spectrum the ratio of benzylic to aliphatic resonances was 1:1.25 which was interpreted to mean that the alkyl chains attached to the carbazole nucleus were short on average. A complete lack of vinyl proton absorption indicated that few alkene bonds if any were present; thus, the degrees of unsaturations must be accommodated by rings or benzo-annulations.</p> <p> Of all the analytical methods used, ammonia chemical ionization mass spectrometry (NH3 CIMS) was found to be a most useful and selective method and was used in probe MS, GC/MS and LC/MS experiments. Reverse phase liquid chromatography (RPLC) was more useful in this work than capillary column gas chromatography (CCGC). A combination of nuclear magnetic resonance (NMR) experiments (1H, 13C, 13C spectral editing, 1H-13C shift correlation and 13C T1 ) was found to be extremely useful for these samples because of the unique information these experiments provided.</p> / Thesis / Master of Science (MSc)
77

Synthesis and structural studies (H-1, C-13, P-31 NMR and X-ray) of new C-bonded cyclotriphosphazenes with heterocyclic substituents from novel phosphinic acid derivatives.

Vicente, V., Fruchier, A., Taillefer, M., Coombes-Chamelet, C., Scowen, Ian J., Plenat, F., Cristeau, H-J. January 2004 (has links)
No / Three new C-bonded cyclotriphosphazenes, [N3P3(2-thienyl)6], 2, [N3P3(3-thienyl)6], 4, and [N3P3(3,3-bithienyl-2,2-ylene)3], 6, have been prepared by two new synthetic procedures and are the first examples of non-spiro and trispirocyclotriphosphazene derivatives composed of thiophene and 3,3-dithiophene substituents, respectively. Their 1H, 13C and 31P NMR parameters are given. The solid state structures of 2, 4 and 6 have been determined by X-ray crystallography.
78

Draft genome sequence of Lysinibacillus sp. strain A1, isolated from Malaysian tropical soil

Chan, K., Chen, J.W., Chang, Chien-Yi, Yin, W., Chan, X. 2015 March 1926 (has links)
Yes / In this work, we describe the genome of Lysinibacillus sp. strain A1, which was isolated from tropical soil. Analysis of its genome sequence shows the presence of a gene encoding for a putative peptidase responsible for nitrogen compounds. / UM High Impact Research Grants (UMMOHE HIR Grant UM C/625/1/HIR/MOHE/CHAN/01, no. A000001- 50001; UM-MOHE HIR Grant UM C/625/1/HIR/MOHE/CHAN/14/1, no. H-50001-A000027)
79

Techniques for measuring pernitric acid, peroxyacyl nitrates, and dinitrogen pentoxide by chemical ionization mass spectrometry

Slusher, Darlene L. 01 December 2003 (has links)
No description available.
80

Biochemical changes in the fermentation bedding of the "pig-on-litter"method of pig farming: with special emphasison biodegradation of nitrogen compounds and odour production

周厚華, Chaw, Donna. January 1996 (has links)
published_or_final_version / Zoology / Doctoral / Doctor of Philosophy

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