Isolation of essential oils from tobacco by gas co-distillation/solvent extraction

Summary The essential oils have been isolated from tobacco leaves using a simple gas co-distillation apparatus. The method involves co-distillation with water under the continuous stream of an inert gas with subsequent single solvent extraction of the distillate. The extract is analysed on GC and GC/MS in splitless injection mode without further concentration. The method was evaluated for reproducibility using n-octadecane as an internal standard. The distillation-extraction procedure was reporducible with an average deviation of ±3% for the major constituents. The present method was applied to the analyses of the essential oils of other agricultural products.Dedicated to Dr. L. S. Ettre on the occasion of his 60th birthday.     

精油化学的进展

本文粗略回顾了精油化学的新进展,对精油的研究方法、精油成分的合成及生源也有所论述。同时介绍了当前精油研究中常用的文献。     

Structure elucidation of triglycerides by chromatographic techniques. Part 1: Capillary GC of ozonized triglycerides

Structure determination of triglycerides according to their number of unsaturated fatty acids (N.U.F.A.) is more easily achieved after ozonolysis of their mixtures (fats and oils) than by capillary gas chromatographic analysis of the mixture as such. Analyses performed before and after ozonolysis of cocoa buttel, hazelnut oil, and a mixture of both fats illustrate the potential of this approach to the structure elucidation of triglycerides by chromatographic techniques.     

Analysis of Essential Oil from the Needles of <Emphasis Type="Italic">Pinus pinaster</Emphasis> Growing in Algeria

The needle oil of the Algerian maritime pine (Pinus pinaster Ait.) growing in natural habitats in Sidi Feradj (Algiers region) was obtained by hydrodistillation in 0.3% yield and analyzed by GC and GC/MS. More than 46 compounds amounting to 65.2% of the total oil were identified. The main components were β-caryophyllene (26.6%), allo-aromadendrene (12.5%), and α-humulene (4.3%). __________ Published in Kimiya Prirodnikh Soedinenii, No. 5, pp. 445–447, September–October, 2005.     

Composition and major odorous compounds of the essential oil of Bifora radians,an aldehyde-producing weed

The composition of the essential oil of Bifora radians, an aldehyde-producing weed, has been investigated by capillary gas chromatography, coupled gas chromatography – mass spectrometry, on-line catalytic hydrogenation and coupled gas chromatography – infrared spectrometry. The nineteen compounds identified included eighteen aldehydes: seven alkanals (C6, C9, C10, C11, C12, C13, and C14), ten alkenals, including five (E)-2-alkenals (C12, C13, C14, C15, and C16), and one (E,E)-2,4-alkadienal (C13). Typical Bifora odors were attributed to three major (E)-2-alkenals, C12, C13, and C14.     

IDENTIFICATION OF LANOSTANES AND THEIR POSSIBLY GEOCHEMICAL SIGNIFICANCE IN BIYANG DEPRESSION

In the study, a series of C_(30)-C_(32) lanostane homologs have been identified from Eogene source rocks and crude oils of Biyang depression in Henan Province, China. Based upon the geochemical investigations and simulating experiments, the idea that the generation of lanostane may mainly be related to the specific original organic inputs and low maturity has been proposed.     

络合滴定法测定钙含量微型实验研究

利用微型滴定法测定含钙制品中的Ca2 含量,并对微型滴定法与常量滴定法的平行测定结果进行了比较。结果两种方法无显著性差异,F检验t检验结果均在允许范围内,相对偏差均小于2.0%,微型滴定法的精度达到常量滴定法测定水平,能满足化学分析要求。     

锂辉石—石灰石烧结中煤粉代替重油作燃料的研究和实践

目前世界锂工业原料以锂辉石为主。我国锂辉石储量居世界首位，主要分布于新疆、四川、湖南等地，其中又以四川的储量占全国第一。锂的主要基础化合物ＬｉＯＨＨ２Ｏ系用锂辉石－石灰石烧结法而得，烧结燃料是影响ＬｉＯＨＨ２Ｏ产品价格的重要因素之一。过去国内外均采用...