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Nitro musks in cosmetic products—determination by headspace solid-phase microextraction and gas chromatography with atomic-emission detection 总被引:1,自引:0,他引:1
Summary The combination of headspace solid-phase microextraction with atomic-emission detection enables highly selective and sensitive
determination of itro musk compounds in cosmetic products. Sample preparation is considerably simplified; there is no solvent
extraction step. Enrichment is influenced by the type and amount of cosmetic product investigated. The lowest amount giving
well detectable peaks is 1 mg musk compound per kg sample. Calibration curves obtained from spiked solutions of selected reference
cosmetics in water show very good linearity. Relative standard deviations of peak areas from repeated measurements are usually
<10%.
Presented at the 21st ISC held in Stuttgart, Germany, 15th–20th September, 1996 相似文献
999.
L. A. Kurdanchenko B. V. Petrenko I. Ya. Subbotin 《Ukrainian Mathematical Journal》1997,49(11):1742-1746
We prove that, in an Artinian module, the upper FC-hypercenter over an infinite FC-hypercentral locally solvable group has a direct complement. Thus, we obtain a generalization of one of Zaitsev’s theorems and one of Duan’s theorems. 相似文献
1000.
R. Souzy B. Ameduri B. Boutevin 《Journal of polymer science. Part A, Polymer chemistry》2004,42(20):5077-5097
The radical co‐ and terpolymerization of 4‐[(α,β,β‐trifluorovinyl)oxy]bromo benzene (TFVOBB) with 1,1‐difluoroethylene (or vinylidene fluoride, VDF, or VF2), hexafluoropropene (HFP), perfluoromethyl vinyl ether (PMVE), and chlorotrifluroroethylene (CTFE) is presented. Although TFVOBB could be thermocyclodimerized, it could not homopolymerize under radical initiation. TFVOBB could be copolymerized in solution under a radical initiator with VDF or CTFE comonomers, while its copolymerization with HFP or PMVE were unsuccessful. The terpolymerization of TFVOBB with VDF and HFP, or VDF and PMVE, or VDF and CTFE also led to original fluorinated terpolymers bearing bromoaromatic side‐groups. The conditions of co‐ and terpolymerization were optimized in terms of the nature of the radical initiators, and of the nature of solvents (fluorinated or nonhalogenated). Various monomer concentrations in the co‐ and terpolymers were assessed by 19F and 1H‐NMR spectroscopy. The thermal and physico chemical properties were also studied. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5077–5097, 2004 相似文献