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51.
Juan Jos Berzas Nevado Rosa Carmen Rodríguez Martín-Doimeadis Francisco Javier Guzmn Bernardo Nuria Rodríguez Farias 《Microchemical Journal》2007,86(2):183-188
An analytical methodology was proposed and validated to be applied to the determination of p,p′-DDT and its metabolites p,p′-DDE and p,p′-DDD in fish oil. The analytical procedure presented in this paper involves a single-step clean up process prior to the analysis. A solution of 1,2,3,4-tetrachloronaphtalene was used as internal standard.The analytical technique used was gas chromatography coupled to an electron capture detector. Details on the validation process are provided.The limits of detection ranged from 2.6 to 4.7 pg μL− 1. The BCR 598 standard reference material (cod liver oil) was used to evaluate the performance of the methodology with satisfactory recoveries for all the compounds.The analytes were determined in three different fish oil pills sold in Spain as a supplementary vitamin support. The sum of p,p′-DDT and metabolites was from 13.2 to 51.3 ng g− 1, the dominant compound being p,p′-DDE. 相似文献
52.
Cebulak S. Langier-Kuüniarowa A. Grotek I. 《Journal of Thermal Analysis and Calorimetry》2002,69(1):227-235
Oxyreactive thermal analysis (OTA) carried out in the conditions of full access of oxygen to each reacting particle of the sample investigated is a suitable method for the determination of important properties of the organic matter dispersed in the rocks. Its results may be easily evaluated to the form of values to be used in a clear diversification and classification system of organic matter/kerogen, as well as to the evaluation of its transformation process in a rockmass. The OTA also enables the distinguishing of the transformation stages and the investigation of the results of the gaseous products liberation from organic matter and kerogen. The OTA method may be applied as a complementary one for the Rock Eval analysis and be used for the organic geochemical and bituminological studies for geological bitumen prospecting.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
53.
高水相W/O型乳化膏体油膜稳定性的研究 总被引:3,自引:0,他引:3
高水相W/O型乳液是指水相体积占74%以上,属于高度不稳定的分散体系[1,2].乳化炸药的问世,使这种高水相W/O型乳液有了新的实际应用.这种炸药是90%~95%重的硝酸铵盐(占水相80%~90%重)水溶液高度分散在5%~10%的油相中构成W/O型乳... 相似文献
54.
多花蔷薇(Rose multiflora. cathayensis)又名红刺玫、刺花,系多年生落叶灌木,野生于甘肃省陇南山区,生长在海拔500~1900 m的山峰、河岸或山坡缘及灌木丛林中,花的资源丰富,是甘肃省目前需开发的野生芳香植物之一,多花蔷薇花为粉红色,花期为5月中旬至5月底,花中含芳香油,可用作化妆、皂用香精等,有关多花蔷薇花的化学成分,未见文献报道,我们将多花蔷薇花的石油醚浸膏用乙醇在0℃脱蜡3次得净油,再经硅胶柱层析分离得纯 相似文献
55.
Bulgaria is a famous world producer of essential oils. Quality control of the lavender oils produced is an important analytical task in view of their wide use in perfumery and cosmetics, the food industry and aromatherapy. The present paper studies the relationship between the trace elements content in lavender inflorescence (Lavandula angustifolia Mill.) and in lavender oil derived from this inflorescence. Three model regions were investigated: two of them are situated far from industrial areas — the village of Zelenikovo and the town of Pavel Banya, and one region is located near the Plovdiv Non-Ferrous Metallurgical Plant. The content of the elements Cd, Cr, Cu, Fe, Mn and Pb in plants was determined after acid digestion by flame and electrothermal atomic absorption spectrometry (ETAAS). Lavender oils were analyzed directly by ETAAS. The results undoubtedly show that there is no strong correlation between the trace elements content in inflorescence and in essential oils. It might be assumed that the trace elements present and accumulated in the inflorescence do not pass in lavender oil during the production by steam distillation. 相似文献
56.
Zai-Chang Y Bo-Chu W Xiao-Sheng Y Qiang W 《Colloids and surfaces. B, Biointerfaces》2005,43(3-4):198-202
The volatile oil of the roots of Cynanchum stauntonii was examined by gas chromatography–mass spectrometry (GC–MS). Thirty-eight constituents were identified. (E,E)-2,4-Decadienal, 3-efhyl-4-methypentanol, 5-pentyl-3H-furan-2-one, (E,Z)-2,4-decadienal and 2(3H)-furanone,dihydro-5-pentyl were found to be the major components. The volatile oil exhibited the activities against influenza virus in vitro (IC50s = 64 μg/ml). In in vivo experiment, it prevented influenza virus-induced deaths in a dose-dependent manner. 相似文献
57.
Summary In the course of our studies on the location of marine products, we have directed our attention to the saponifiable fraction of the liver oil from the deep sea shark (Centrophorus squamosus). Different analytical and preparative techniques, such as high-performance liquid chromatography (HPLC), countercurrent chromatography (CCC), and gas chromatography-mass spectrometry [GC-MS, electron impact (EI) and positive-ion chemical ionization (PCI)] were used. These methods allowed us to characterize, after various derivatizations, most of the fatty acids formed after the saponification of the oil, and to purify two of them, namely: docosahexaenoic acid (DHA or 226) and docosamonoenoic acid (DMA or 221). 相似文献
58.
59.
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. 相似文献