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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

Glass capillary gas chromatographic analysis for trace amounts of cyclopropenoid fatty acids

Ryan, Daberath 09 March 1987 (has links)
Dietary cyclopropenoid fatty acids (CPFA) have long been known to cause pronounced physiological disorders in both farm and laboratory animals. Past work has shown CPFA to be a powerful promoter of carcinogenesis in trout, rats and mice. Sterculic and malvalic acids (CPFA's) are found in seed lipids of plants from the order Malvales. Two members of this order are cotton and kapok, both of which are used extensively as cooking oils for human consumption. Present chemical and instrumental methods of analysis for CPFA are effective only at CPFA levels above 0.1%, and accurate only at levels above 1%. A more sensitive method of analysis was developed exploiting recent technological advances in glass capillary gas chromatography (GCGC). By the use of cold on-column injection, and positioning of the column at the base of the detector flame, this method eliminates two problem areas found in other GC methods. The other common component involved in CPFA decomposition, during GC analysis, is the column. Vitrious silica columns with an inert stationary phase, SE-30, were shown to separate the highly reactive CPFA without decomposition. Proof of stability during analysis was obtained by changing the variables of relative time on column and column temperature. This method not only allows individual determination of sterculic and malvalic acid concentrations, it is rapid, accurate (to the 70 parts per million range), and is superior to other instrumental and chemical methods. The CPFA concentration for okra, hollyhock, cheese weed, seashore mallow, kapok, and white cap cottonseed oil are as follows: 0.3% to 0.92%, 0.33%, 2.6%, 2.6%, 12.8%, and 75ppm, respectively. The two different values for okra were found because seeds from two different growing seasons were analyzed. No CPFA could be detected in Diet Imperial Margarine, raw cocoa beans, cocoa butter or Lucca's winterized cottonseed oil. / Graduation date: 1987
2

An investigation of perfluorocarbons and bromofluorosilanes : pyrolysis, GC-ECD, GC-MS, FTIR and microwave spectroscopic studies and analysis

O'Mahoney, T. Karl P. January 1994 (has links)
No description available.
3

Development of a gas-liquid chromatography procedure for allopurinol and oxipurinol

Kessler, James Rolland January 1979 (has links)
No description available.
4

Gas chromatographic trace analysis of water in ethanol and its application to a problem in paper chromatography

Weinberg, Betty Bell Woodward, 1938- January 1962 (has links)
No description available.
5

The measurement of air-fuel ratios and products of combustion by means of gas chromatography techniques

Day, Seth Sears, 1926- January 1965 (has links)
No description available.
6

Gas-phase characterization of the molecular electronic structure of metal clusters and metal cluster oxidation

Cobb, Stephen Hal 08 1900 (has links)
No description available.
7

Construction and validation of a GC-ICP-MS instrument for the analysis of organometals and other trace element species

Kim, Alexander Walter January 1993 (has links)
No description available.
8

Diffusion And Equilibrium Measurements In Polymer-Solvent Systems By Inverse Gas Chromatography Method/

Eser, Hülya. Tıhmınlıoğlu, Funda January 2004 (has links) (PDF)
Thesis (Master)--İzmir Institute of Technology, İzmir, 2004. / Includes bibliographical references (leaves. 82-84).
9

Development of high speed hyphenated chromatographic analyzers and second order data analysis techniques /

Prazen, Bryan J., January 1998 (has links)
Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [129]-140).
10

The gas chromatographic separation of ortho and para hydrogen and gas chromatographic instrumentation

Christoffersen, Donald John, January 1966 (has links)
Thesis (Ph. D.)--University of Wisconsin, 1966. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.

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