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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.
61

The effect of metallic halides on some Grignard reactions ...

Lambert, Frank Lewis, January 1942 (has links)
Thesis (Ph. D.)--University of Chicago, 1942. / Lithoprinted. Includes bibliographical references.
62

A radical pathway for reductive dehalogenation and nucleophilic substitution of hetaryl halides

Oestreich, Terence Miller, January 1973 (has links)
Thesis--University of Florida. / Description based on print version record. Typescript. Vita. Bibliography: leaves 159-164.
63

The effect of metallic halides on certain Grignard reactions: I. The effect of metallic halides on the reaction of sterically hindered acid halides with methylmagnesium iodide. II. The effect of metallic halides on the reaction of sterically hindered esters with Grignard reagents ...

Morrison, Robert Thornton, January 1944 (has links)
Thesis (Ph. D.)--University of Chicago, 1944. / Lithoprinted. Includes bibliographical references.
64

Investigations of the quaternary M/MC1₄/X₈/A1₂C1₆ systems (where M - Zr, Ti, and X₈ - Se₈, S₈) and related melts

Jensen, William Barry. January 1982 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 275-285).
65

Thermoluminescence and related properties of the alkali halides

Heckelsberg, Louis Fred, January 1951 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1951. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 73-75).
66

Slanted layer photonic structures in silver-halide gelatin emulsions /

Yau, Suet Man. January 2006 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2006. / Includes bibliographical references (leaves 58-60). Also available in electronic version.
67

Some aspects of organo-phosphorus, -arsenic, and -antimony halides

Farhat Ali, Mohammad January 1968 (has links)
No description available.
68

A study of some organoarsenic and organoantimony halides

Khan, Abdullah January 1986 (has links)
Triarylarsine halides The reactions of tri(2-, 3-, 4-methylphenyl)-, tri(dimethylphenyl)-, tri(2-, 3-, 4-fluorophenyl)-, tris(2-, 3-, and 4-trifluoromethylphenyl)arsine with halogens (bromine, iodine and iodine bromide) have been studied by conductometric titration in acetonitrile. In general, evidence was obtained for the formation, in solution, of 1:1 and 2:1 adducts (R3AsX2 and R3AsX4). All of the possible 1:1 and 2:1 adducts were isolated as crystalline solids and the electrolytic conductivity of their acetonitrile or nitrobenzene solutions was measured. The molar conductivity value for each compound (at Cm = 0.01 mol dm−3) was calculated. All of the compounds of type R3AsCl2 are weak electrolytes except (2-CH3C6H4) 3AsCl2 which is a medium electrolyte; and all of the R3AsBr2 compounds are weak or medium electrolytes except (2-CH3C6H4) 3AsBr2 which has a molar conductivity value approaching that of a strong electrolyte. The molar conductivity values of the dibromide adducts are always higher than those of the corresponding dichloride adducts. Comparison of the relative values of the molar conductivity of the adducts (YC6H4) 3AsX2 [Y = H, CH3, F, CF3 and X = Cl, Br] with the relative values of acid strengths of the corresponding substituted benzoic acids, YC6H4COOH, is made. The higher molar conductivity of R3AsI2 and R3AsIBr results from their disproportionation R3AsX2 □(→┬ ) 1⁄2 R 3 As + 1⁄2AsX+X3 All of the 2:1 adducts, R3AsX4 are strong electrolytes in acetonitrile solution and are formulated R3AsX+ X3−. The mixed tetrahalides R3AsCl3I and R3AsBr3I, were indicated from the reactions of R3AsCl2 with ICl and R3AsBr2 with IBr, and they can be obtained as solid adducts. These compounds ionise completely in acetonitrile and the halogen of lower atomic number resides, without exception, in the cation R3AsCl3I  R3AsCl+ICl2− R3AsBr3I  R3AsBr+ IBr2− Triarylstibine halides The course of the reactions of tri(2-, 3-, 4-methylphenyl)-, tri(dimethylphenyl)-, tris(2-, and 4-trifluoromethylphenyl)stibine with bromine, iodine and iodine bromide in acetonitrile solution were investigated by conductometric titration in order to observe compounds formation in these systems. All of the 1:1 and 2:1 adducts (R3SbX2 and R3SbX4) whose existence was shown by the titrations were isolated. The electrolytic conductivity of acetonitrile solutions of the adducts were measured and values of molar conductivity were obtained; all of the compounds of general formula R3SbX2 (X = Cl or Br) are either non-electrolytes or very weak electrolytes in acetonitrile. The conductivity of the adducts R3SbI2 and R3SbIBr are high and arise from their disproportionation in acetonitrile: R3SbI2 ⇄ 1⁄2R3Sb + 1⁄2R3SbI+I3− R3SbIBr⇄ 1⁄3R3Sb + 1⁄3R3SbBr2 + 1⁄3R3SbBr+I3− All of the tetrahalides except (4-CF3C6H4)3SbI4 are strong electrolytes. The conductometric titrations of R3SbCl2 with ICl and SbCl5 and R3SbBr2 with IBr [R = (CH3) 2C6H3, 2-CF3C6H4] have been studied in acetonitrile; there is no reaction between R3SbCl2 and ICl but with SbCl5 a highly conducting 2:1 adduct (R3SbCl+ Sb2Cl11−) is formed. With the exception of [(CH3)2C6H3]3SbBr2, the reaction of R3SbBr2 with IBr does not go to completion, but produces an equilibrium mixture of reactants and product: R3AsBr2 + IBr  R3SbBr+ IBr2− No solid adduct was obtained. However the adduct [(CH3)2C6H3]3SbBr3I, suggested from the titration graph, was isolated as a solid. It is a strong electrolyte in acetonitrile solution. Tetraphenylstibonium halides. All of the compounds Ph4SbX (X = F, Cl, Br, I) and Ph4SbX3 (X3 = Br3, IBr2, Icl2) were isolated as crystalline solids. Their electrolytic conductivity was measured in acetonitrile and the molar conductivity was calculated for each compound; Ph4SbF is a very weak electrolyte. Ph4SbCl and Ph4SbBr are weak electrolytes but Ph4Sbl is a strong electrolyte as are all of the trihalides, Ph4SbX3. The conductometric titrations of Ph4SbCl with ICl and Ph4SbBr with Br2 and IBr indicate that the trihalides Ph4SbX3 are formed readily in acetonitrile solution.
69

The preparation and use of sterically hindered organotin compounds

Brown, Paul January 1989 (has links)
No description available.
70

The crystal chemistry of heptadecyl- and octadecyl- containing n-alkylammonium halides and esters

Rademeyer, Melanie 27 August 2012 (has links)
M.Sc. / Molecules containing a long saturated carbon chain are present in many natural and commercial products. Due to the conformational flexibility of the carbon chain, different molecular conformations of these molecules are possible resulting in polymorphism. The crystal structure of a material greatly influences its chemical and physical properties, leading to different properties for different polymorphs. Designing materials with specific properties requires the understanding of the underlying fundamental parameters and forces influencing the packing of molecules in the crystal. A thorough literature study was conducted to determine the crystallographic research that has been done long chain compounds. Not only did this literature study lead to the identification of possible research fields, but also provided a solid background concerning the crystallographic behavior of these systems. In this project we investigated the polymorphism of simple molecules containing a saturated carbon chain with seventeen or eighteen carbons. Two systems are investigated namely n-alkylammonium halides and esters of fatty acids. By varying crystallization conditions different polymorphs of each compound can be obtained. Various experimental techniques were employed to shed light on the structure and packing of the long chain molecules in the different polymorphs. The crystal structure of the low temperature polymorph of n-octadecylammonium bromide was determined, as well as the cell dimensions of the low temperature form of noctadecylammonium chloride. The unit cell dimensions of n-octadecylammonium iodide monohydrate was also determined. The structures of the methyl and ethyl esters of noctadecanoic acid and the symmetrical -ester heptadecyl-heptadecanoate was investigated. In this project a young, dynamic research field was investigated. This led to the identification of other possible fields of study. Because there are not many reports in the literature on the crystallographic characteristics of these compounds, the evolving of the project required a lot of creativity.

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