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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.
1

Manganese(III) acetate mediated synthesis of oil dispersants

Marriott, Stephen Nigel January 2001 (has links)
No description available.
2

A Vectorized Font Personalizing System

Hsieh, Chung-Hsun 19 July 2007 (has links)
With the advent of industrial revolution, machines replace the traditional human power. Even though both the quantity of merchandise produced increases and per unit cost decreases dramatically, the stereotypical outlook of mass-produced goods drives the human innate quest for recognizable traits to differentiate among otherwise homogeneous products. A font personalizing system is proposed to transform standard Chinese vector font, according to a writer¡¦s handwritten characteristics, into a personalized font possessing writer¡¦s discernible features. In the proposed font personalizing system, a radicals-contours-line segments-control points four-level hierarchical approach is taken in analyzing a Chinese character. Both standard and handwritten characters are decomposed into constituent radicals first. The number of contours of every radical, the number of connected line segments making up each contour and the control points forming each line segment are then derived. The resulting ensemble of information is later used for finding the radical correspondence between standard characters and handwritten ones. Once the correspondence is established, the height-width ratio of handwritten radicals, together with the length and slope of line segments are utilized to modify the matching counterparts in all characters of a standard Chinese font set. In this manner, the representing features extracted from only a limited number of handwritten characters can be used to automatically modify a full set of Chinese fonts. The personalized font set obtained can efficiently replace existing standard fonts to exhibit unique handwritten features.
3

Assessing domestic right-wing extremism using the theory of collective behavior

Baldoza, Arnold C. January 2009 (has links) (PDF)
Thesis (M.A. in Security Studies (Homeland Security and Defense))--Naval Postgraduate School, December 2009. / Thesis Advisor(s): Rasmussen, Maria. Second Reader: Dahl, Erik. "December 2009." Description based on title screen as viewed on January 27, 2010. Author(s) subject terms: Domestic right-wing extremism, domestic far right, far right, terrorism, theory of collective behavior, right-wing extremism. Includes bibliographical references (p. 101-129). Also available in print.
4

Radical-mediated modification of polyolefins: investigation of the synthesis of graft copolymers

Kaufman, Michael Steven 08 May 2008 (has links)
A range of strategies exist for the production of polyolefin block copolymers with well-defined morphologies for the compatibilization of immiscible blends; however, high sensitivity to impurities and use of expensive transition-metal catalysts limit their economic viability. An alternative method is the solvent-free coupling of dislike polymers using peroxides and multifunctional coagents. This technique, however, does not distinguish between a blend of gelled homopolymers and the intended copolymer. The use of a solution-based approach, like the one described in this report, for the radical-mediated coupling of polyolefins with dislike polymers allows for the full characterization of the copolymer without the formation of gel. A one- and two-step synthesis for the coupling of two homopolymers in solution is demonstrated using triallyl trimesate. The one-step approach produced a copolymer in low yields due to the differences in reactivity between the homopolymers. The two-step synthesis consisted of the solvent-free grafting of the coagent to the less reactive polymer, followed by coupling in solution with the other polymer. Though this technique demonstrated improved yields over that of the one-step approach, the overall yields were limited due to the dilution effects of the high solvent levels needed for comiscibility. The coupling of polyethylene with poly(ethylene oxide) had a maximum graft yield of 9.5%, whereas the coupling between polypropylene and a thermoplastic polyolefin elastomer was negligible. It was found that the grafting of allylic ester coagents to polyethylene results in an uneven graft distribution. Given enough peroxide and coagent, the material will reach its gel point where there is a small, high molecular weight population with a disproportionately high graft content, while the remaining chains contained a modest concentration of bound coagent. Furthermore, a survey of the effectiveness of several common coagents in the radical-mediated crosslinking of polyethylene was investigated where it was found that allylic coagents had a greater contribution to the crosslink density of the resin than vinyl coagents. / Thesis (Master, Chemical Engineering) -- Queen's University, 2008-05-06 19:37:13.916
5

Bredt's Rule stabilization and destabilization of nitrogen-centered radicals

Kessel, Carl Richard. January 1979 (has links)
Thesis--University of Wisconsin--Madison. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 256-273).
6

Tetraalkylhydrazine radical cation geometry and aminium catalyzed reactions of 1,2-dialkylpyrazolidines

Yumibe, Nathan Paul. January 1985 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1985. / Typescript. Vita. Description based on print version record. Includes bibliographical references (leaves 200-206).
7

Reactions and identification of radicals produced by photochemical methods and gamma irradiation in branched alkane glasses

Arce Quintero, Rafael Angel, January 1970 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
8

The reactions of free radicals at metallic surfaces

King, Peter, January 1942 (has links)
Thesis (Ph. D.)--Catholic University of America, 1942. / Reproduced from type-written copy. Bibliography: p. 25.
9

Kinetic study of the gernation and reactions of allyl and cyclopropyl radicals in the gas phase

Kambanis, Stamatis M. January 1967 (has links)
Allyl and cyclopropyl radicals were generated in the gas phase at a mean temperature of 140°C by new methods which promise to be of general application. Thus the radical R• may be generated by either of the two sequences: [formulas omitted] The addition-dismutation sequence was used to generate the allyl radical from allyl 3-butenoate and from diallyl oxalate, and the cyclopropyl radical from allyl cyclopropyl-carboxylate and from cyclopropyl 3-butenoate. The meta-thesis-dismutation sequence was tested for the generation of methyl radicals from the methyl ester of cyclohexa-1,4-diene-3-carboxylic acid, and applied to the generation of allyl radicals from the corresponding allyl ester. The Arrhenius parameters of the generating sequence reactions for every system were measured and discussed. These methods generate R• radicals in the presence of an excess of the sensitizing radicals, so that the present systems allow the observation of the patterns of R•/C₂H•₅ interaction. Allyl radicals were generated in the absence of appreciable amounts of other radicals, in the gas phase, by the u n s e n s i t i z e d thermal decomposition: C₃H₅OOCCOOC₃H₅ → 2C₃H•₅ + 2CO₂ log k(sec.⁻¹) = (14 ± 1) - (37 ± 2)10³/2.3RT Allyl radicals were also generated in the presence of an equal amount of cyclohexadienyl radicals in the gas phase by the unsensitized thermal decomposition: [formula omitted] log k(sec.⁻¹) = (14 ± 1) - (38 ± 3)10³/2.3RT The Arrhenius parameters of these two decompositions indicate that all the bonds which are finally broken are significantly extended in the transition state. The combination, disproportionation, isomerization, and metathesis reactions were investigated for the allyl and cyclopropyl radicals. Typical results include: [formulas omitted] / Science, Faculty of / Chemistry, Department of / Graduate
10

Electron spin resonance of electrolytically generated nitro- and cyano anion radicals.

Fischer, Peter Hans Herman January 1963 (has links)
The radical anions of 1,2-dinitrobenzene, 1,3-dinitro-benzene, 1,3-dinitrobenzene-d₄, 1,4-dinitronaphthalene, 1,5-dinitronaphthalene, 1,8-dinitronaphthalene, 1,3,5-trinitrobenzene, 2,2', 4,4',6,6'-hexanitrobiphenyl, 1,2-dicyanobenzene, 1,4-dicyanobenzene, 1,2,4,5-tetracyanobenzene, and 7,7',8,8'-tetracyanoquinodi-methane have been generated by electrochemical means, and the electron spin resonance spectra recorded. The spectra have been analyzed completely in terms of the various coupling constants consistent with the symmetry of the paramagnetic species. In the isomeric dinitrobenzenes, evidence is presented which indicates that the spin density at the N¹⁴ nuclei is positive. A very large anomaly in the ESR spectrum of 1,3-dinitrobenzene radical anion is explained by assumption of rotational isomerism. A relation is presented, expressing the nitrogen coupling constants of the nitro group N¹⁴ nuclei in terms of the spin density distribution of the radical anion, calculated by the simple Huckel M.O. method. Anomalous behaviour of the 1,3,5-trinitrobenzene system is explained in terms of an electron-donor-acceptor complex between radical anion and neutral molecule. The results obtained for the cyanoaromatic anions have been compared with those of Fraenkel et al. with the exception of 7,7',8,8'-tetracyanoquinodimethane anion radical, for which a more detailed discussion is presented. C¹³ splittings have been calculated theoretically and found to agree reasonably well with experimentally determined values. For the TCNQ¯ species, evidence is also present which indicates a positive spin density at the N¹⁴ nuclei. / Science, Faculty of / Chemistry, Department of / Graduate

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