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Thesis (Ph. D.)--New York University. / eContent provider-neutral record in process. Description based on print version record. Bibliography: p. 35.

Thesis (Ph. D.)--New York University. / Bibliography: p. 35.

This thesis discusses an investigation of film condensation of steam on the outside surface of an inclined cylinder. The objectives of the investigation were (1) to obtain heat-transfer coefficients for steam condensing on an inclined cylinder, (2) to determine the effect of the angle of inclination of the cylinder on the condensing coefficient, and (3) to verify values of the coefficient obtained from an accompanying theoretical development. Experiments were conducted for steam condensing on a 12.45 in. length of the outside surface of a 3/4 in. diameter by 0.065 in. thick wall, water-cooled, copper tube. Condensing coefficients were obtained for inclinations to the horizontal from 0° to 90° at 15° intervals. It was found that these coefficients decreased in value as the angle of inclination increased from 0° to 90°. At the same time good agreement was obtained between the measured and theoretical coefficients. No single equation could be found which would correlate the results for all the inclinations tested, but general equations were obtained which apply for each of two zones. One zone included inclinations from 0° to 30°, the other inclinations from 45° to 90°. The zone from 30° to 45° requires more investigation before it can be satisfactorily correlated. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate

Call number: LD2668 .T4 1952 M61 / Master of Science

Thesis (Ph. D.)--Columbia University, 1920. / Vita.

Thesis (Ph. D.)--Columbia University, 1932. / Vita. Bibliography: p. 31.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1949. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

The problem initially presented was the structural elucidation of a compound obtained when 2,5-dimethylpyrrole was subjected to conditions of acidic reduction. Previous workers had assigned a molecular formula C₁₂H₁₇N to this product and a partial structure had been put forward based on the indolenine system. In the course of this work it was found that the compound obtained by these earlier workers was the result of a reductive self-condensation of 2,5-dimethylpyrrole, and Its structure was conclusively established as 1,3,4,7-tetramethylisoindoline. The methods used in the structural elucidation of this product included elemental analysis of its derivatives, measurement of its basicity and equivalent weight, infrared and ultraviolet spectroscopic evidence, oxidative degradation, and its proton magnetic resonance spectrum. Two related isoindolines were prepared by different routes. 2,4,7-trimethylisoindoline was synthesised by methods analogous to those already known, and the ultraviolet spectrum of its methiodide, when compared with that of the methiodide from 1,3,4,7-tetramethylisoindoline, reinforced the structural assignment of the latter. 1,3-diphenyl-4,7-dimethylisoindoline was obtained by the reductive condensation of acetonylacetone with 2,5-diphenylpyrrole (which did not undergo self-condensation). The favourable result of this reaction suggested that a similar condensation may have occurred to give the 1,3,4,7-tetramethylisoindoline and also admitted the possibility of a general synthesis of substituted isoindolines by this route. An attempt was made to resolve the mechanism of the 2,5-dimethylpyrrole condensation, for which either a Diels-Alder reaction or a ring-opening process may be postulated. The failure of the dimethylpyrrole to show dienic character, even in the presence of very strong dienophiles, together with positive evidence for ring-opening and ketone-pyrrole condensation argued forcibly for the latter mechanism. / Science, Faculty of / Chemistry, Department of / Graduate

Isoxazoles and isoxazolines have been shown in the literature to be an important scaffold for pharmaceuticals and insecticides, as well as a source of synthetic versatility important to many syntheses. As a substitute for other aromatic rings, isoxazoles are known to change the efficacy of a given compound. Isoxazolines can be used as a precursor to many other functional moieties that may be effected during earlier synthetic steps. There are many routes to the heterocyclic moiety, allowing for their insertion in a wide range of molecules. Our group has previously reported a condensation of arylaldehydes with hydroxylamine to first make an aryloxime which can, after generating the nitrile oxide, then cyclize with an alkene or alkyne in situ and create the isoxazoline or isoxazole, respectively. The Knoevenagel Condensation reaction is identified as the addition of an activated methylene complex, malononitrile or cyanoacetamide, with a carbonyl followed by dehydration.. Our group has previously reported a facile, one-pot reductive alkylation of benzyl malononitriles. These compounds have been noted as having many insecticidal uses, as well as being potent pharmacophores. The scope of this project is to further explore and optimize the condensation of aryl aldehydes and methylene complexes. The condensed and reduced methylene complex will then be alkylated to join the heterocyclic moiety to reach the final disubstituted methylene product. A second approach will also be explored in which the monosubstituted malononitrile will first be alkylated with allyl or propargyl bromide, which can then undergo a 1,3-dipolar cycloaddition with a nitrile oxide. The library of compounds generated will be sent to collaborators to test the biological activity of the molecules. / Introduction and background literature -- Reactions of methylene complexes -- Synthesis of disubstituted methylene complexes. / Department of Chemistry