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Multiresidue analysis of pesticides in soil by supercritical fluid extraction/gas chromatography with electron-capture detection and confirmation by gas chromatography-mass spectrometry
(Amer Chemical Soc, 2005-01-12)
The applicability of supercritical fluid extraction (SFE) in pesticide multiresidue analysis (organohalogen, organonitrogen, organophosphorus, and pyrethroid) in soil samples was investigated. Fortification experiments ...
Gas Chromatographic Determination of Cyprodinil, Fludioxonil, Pyrimethanil, and Tebuconazole in Grapes, Must, and Wine
(1997-07-01)
A rapid and simple gas chromatographic method for determinating cyprodinil, fludioxonil, pyrimethanil, and tebuconazole in grapes, must, and wine is described. An on-line microextraction method was used with a one-step ...
Identification of triterpenes and sterols from pterogyne nitens (fabaceae-caesalpinioideae) using high-resolution gas chromatography
(Soc Chilena Quimica, 2009-09-01)
As part of our ongoing bioprospecting studies on secondary metabolites in plants of Cerrado and Atlantic Rain Forest of São Paulo State (Brazil), we describe the identification of triterpenes and sterols present in the ...
Screening Brazilian automotive gasoline quality through quantification of saturated hydrocarbons and anhydrous ethanol by gas chromatography and exploratory data analysis
(Vieweg, 2007-05-01)
In this paper a set of Brazilian commercial gasoline representative samples from São Paulo State, selected by HCA, plus six samples obtained directly from refineries were analysed by a high-sensitive gas chromatographic ...
A simple and rapid extraction for gas chromatographic determination of thiabendazole and imazalil residues in lemons
(2002-01-01)
A rapid and efficient method is described for the determination of thiabendazole and imazalil residues in lemons (peel and pulp). The procedure is based on the extraction with an hexane:ethyl acetate mixture (1:1, v/v) and ...
Correlation between mandibular gland secretion and cuticular hydrocarbons in the stingless bee Melipona quadrifasciata
(2012-08-28)
We investigated whether Melipona quadrifasciata worker mandibular gland secretions contribute directly to their cuticular hydrocarbon profile. The mandibular gland secretion composition and cuticular surface compounds of ...