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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

The Analysis of some South African essential oils by comprehensive two-dimentional gas chromatography (GCxGC)

Zellelow, Amanuel Zeru 25 April 2005 (has links)
By virtue of their fragrance and therapeutic nature, essential oils have gained great application in the cosmetic and pharmaceutical industries. These oils, as products consumed by the public for the general health and cosmetics, should be of high quality and unadulterated. In this project comprehensive two-dimensional gas chromatography (GCxGC) was used for the qualitative analysis of some South African essential oils. The main purpose of the project was to evaluate GCxGC for identification of essential oil constituents and for fingerprinting the different essential oils for quality control purposes. Essential oils of the same kind but of different origin were compared and the quantitative variation between their components was studied. Gas chromatography-time-of flight mass spectrometry (GC-TOFMS) as well as comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GCxGC-TOFMS) was used to help identify component peaks separated in the GCxGC instrument. Once certain precautions are taken and the delicate modulator is correctly optimized, the GCxGC results are reproducible and easy to interpret. Overall, the GCxGC technique utilized showed good promise for quality control of essential oils. / Dissertation (MSc)--University of Pretoria, 2006. / Chemistry / unrestricted
2

The odor components of the defense mechanism of the "green worm", Amynthas hupeiensis and wheat insect repellent in bay leaves, (Laurus nobilis, L.)

Saim, Norashikin. January 1985 (has links)
Call number: LD2668 .T4 1985 S245 / Master of Science

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