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A totally new solid stationary phase deposition technique for micro machined gas chromatography (GC) columns fabrication was proposed: to overcome the limitations of conventional liquid (or occasionally solid) stationary phases in terms of very volatile compounds retention and/or clean room batch production, an approach consisting of the collective direct deposition of the adsorbent in micro columns channels by sputtering was performed. The process was fully compatible with clean room fabrication flow and industry-ready, with very good precision results. Silica, alumina, graphite and magnesia were proven able to separate volatile hydrocarbons. Various types of columns (structure, stationary phase) were fabricated in the form of 2x2 cm² silicon-Pyrex chips, and their thermodynamic and kinetic evaluations were reported. Retentions were observed to increase from magnesia to graphite through alumina and silica and with phase ratio decrease, as expected; very satisfying efficiencies were obtained: more than 5700 plates, and 250 µm-high plates. The possibility to use such columns for fast in-situ and autonomous monitoring of light hydrocarbons in oilfield environments was demonstrated by the implementation of a chip temperature-programming system and various versatility tests (high temperatures, carrier gas, humidity): a complete C1-C9 linear alkanes separation was performed in less than 15 seconds, as well as complex mixtures fast separations (isomers, unsaturated), and an industrial confidential application was developed and patented. Therefore, sputter-deposited stationary phase micro columns opened numerous perspectives for the developments of miniaturized GC apparatuses.

The technique of Inverse Gas Chromatography (IGC) was employed for the study of the interactions between various organic solvents with various types of the major inorganic materials (clay minerals and sand) found in Albertas oil sands. Heat of adsorption (-H) was measured for each solvent with respect to each of the four studied inorganic materials. The calculation we used was based on the Infinite Dilution Thermodynamics approach used by Katsanos et. al. [Journal of Chromatography A. 795, 133-184 (1998)]. Retention time data is converted into Retention Volume; H is then obtained by a plot vs. 1/T. The solvents studied were straight chain, branched and cyclic alkanes, alkenes, aromatics, and ketones. The inorganic materials studied were kaolinite, illite, illite-smectite mixed layer, and sand. Our results show that solvents had significantly less affinity for sand when compared to the three types of clay studied. Additionally, solvent affinity to illite had appreciable difference when compared to kaolinite and the mixed layer of illite-smectite. Furthermore, increase in carbon number leads to increased adsorption to the clay. Branched or cyclic alkanes have slightly lower adsorption to clay when compared to straight chain alkane of the same carbon number. Double bonds significantly increase solvent affinity to clay, but have no effect on sand. Lastly, alcohols and ketones have very high affinity to clay that no elution occurred when either solvent was injected into the GC and only ketone eluted when sand was the stationary phase in the GC column. / Chemical Engineering

En la presente tesis se ha valorado la histamina y sus principales metabolitos, mediante el uso de técnicas de cromatografía de gases y espectrometría de masas. En concreto, se ha desarrollado un nuevo método de análisis, sensible y específico, para obtener un perfil metabólico de la histamina y sus derivados.

Thesis (Ph.D.)--Tufts University, 2000. / Submitted to the Dept. of Chemistry. Adviser: Albert Robbat, Jr. Includes bibliographical references. Access restricted to members of the Tufts University community. Also available via the World Wide Web;

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2004. / Härtill 4 uppsatser.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 5 uppsatser.

Thesis (MSc)--University of Stellenbosch, 2007. / Bibliography. Also available via the Internet.

Diss. (sammanfattning) Umeå : Univ., 2007. / Härtill 5 uppsatser.

Thesis (MSc.(Chemical Pathology)--Faculty of Health Sciences)-University of Pretoria, 2008. / Summary in English and Afrikaans. Includes bibliographical references.