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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 ...
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 ...
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 ...
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 ...
Quantitative determination of furocoumarins in samples of Carapia by capillary gas chromatography
(Vieweg, 1999-07-01)
The occurrence of furocoumarins in the Moraceae has already been demonstrated. We present here the results concerning the chemical composition and quantification of furocoumarins from carapia (Dorstenia species, Moraceae) ...
Identification of polycyclic aromatic hydrocarbons in sugar cane soot by gas chromatography mass spectrometry
(Vieweg, 1997-12-01)
Fly soot samples collected in the sugar cane fields after the process of burning were extracted in a Soxhlet apparatus (methylene chloride:methanol 4:1). The extracts were fractionated on silica gel Sep-Pak cartridges into ...
Quantitative determination of furocoumarins in samples of Carapia by capillary gas chromatography
(Vieweg, 1999-07-01)
The occurrence of furocoumarins in the Moraceae has already been demonstrated. We present here the results concerning the chemical composition and quantification of furocoumarins from carapia (Dorstenia species, Moraceae) ...