Spme
Mostrando 25-36 de 196 artigos, teses e dissertações.
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25. Measurement of Activity Coefficients at Infinite Dilution for Alcohols in [BMIM][CH3SO4] using HS-SPME/GC-FID
ABSTRACT The activity coefficient at infinite dilution (&IN1) and distribution ratios at infinite dilution (&IN2) were determined for alkanols (methanol, ethanol, 1-propanol, 1-butanol, 2-butanol, and 2-methyl-2-propanol) in the ionic liquid (IL) 1-butyl-3-methylimidazolium methyl sulfate ([BMIM][CH3SO4]) by HS-SPME (Headspace - Solid Phase Micro Extraction
Braz. J. Chem. Eng.. Publicado em: 2017-07
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26. Study of Viability of Solid-Phase Microextraction, in vivo, in the Extraction of Microbial Volatile Organic Compounds Associated to the Pigment Production Process by the Monascus Fungus, in Submerged Fermentation
Microbial volatile organic compounds (MVOCs) are present in several production processes in biotechnology. In this study it is evaluated the viability of use of a method involving solid-phase microextraction (SPME), in vivo SPME, in the extraction of MVOCs, associated with the pigment production process by the Monascus fungus. PDMS/Car/DVB (50/30 µm) fiber
J. Braz. Chem. Soc.. Publicado em: 2017-06
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27. VALIDAÇÃO DE MÉTODO POR MEFS-HS/CG-EM PARA DETERMINAÇÃO DE CARBARIL EM PLASMA SANGUÍNEO
The aim this research is to develop a HS-SPME/GC-MS method to analyze the carbaryl in blood plasma samples of the rural workers, who live round the perimeter of Chapada do Apodi-CE. This was achieved by chromatographic signal of the 1-naftol, degradation product of carbaryl with the intention of evaluating the degree of exposure of the workers to pesticides,
Quím. Nova. Publicado em: 2017-06
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28. Strategy for Correction of Matrix Effect on the Determination of Pesticides in Water Bodies Using SPME-GC-FID
This paper investigates a strategy as a quality control parameter, using standard surrogate and determination of a relation factor for determination of parathion-methyl, chlorpyriphos and cypermethrin pesticides in environmental aqueous matrices with distinct characteristics (river water, estuarine, seawater and weir water), using the technique of solid phas
J. Braz. Chem. Soc.. Publicado em: 2017-06
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29. HS-SPME optimization and extraction of volatile compounds from soursop (Annona muricata L.) pulp with emphasis on their characteristic impact compounds
Abstract Aroma and taste are decisive factors in the selection of any food. The aim of this study was to extract the volatile compounds present in soursop (Annona muricata L.) pulp by Solid-phase microextraction (SPME) technique using 3 different fibers (DVB/CAR/ PDMS, CAR/PDMS and PDMS/DVB). An experimental design was set up to evaluate the best extraction
Food Sci. Technol. Publicado em: 29/05/2017
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30. Evaluation of volatile profiles obtained for minimally-processed pineapple fruit samples during storage by headspace-solid phase microextraction gas chromatography-mass spectrometry
Abstract This paper describes the application of the solid-phase microextraction (SPME) technique for the determination and monitoring of the volatile profile of minimally-processed pineapple fruit stored at various temperatures (-12 °C, 4 °C and 25 °C) for different periods (1, 4 and 10 days). The SPME fiber coating composed of Car/PDMS presented the bes
Food Sci. Technol. Publicado em: 09/03/2017
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31. Problemas en el análisis de metilsiloxanos volátiles (VMS): origen y soluciones
Volatile methylsiloxanes (VMS) are pollutants widely distributed in the environment due to its extensive uses and high volatility. The analysis of these compounds is commounly performed by gas chromatography - mass spectrometry (GC-MS), and it is dificult due to the presence of background contamination and volatile losses. Different preconcentration techniqu
Quím. Nova. Publicado em: 2017-02
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32. HS-SPME AS AN EFFICIENT TOOL FOR DISCRIMINATING CHEMOTYPES OF Lippia alba (Mill.) N. E. Brown
Lippia alba (Mill.) N. E. Brown (Verbenaceae) is a medicinal plant for which several biological activities are reported, such as sedative, anxiolytic, anti-ulcer, antifungal, antimicrobial, antioxidant, antispasmodic, anti-nociceptive and anti-inflammatory. It is characterized by the production of essential oils which have been used to classify the plant in
Quím. Nova. Publicado em: 2017-01
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33. Determination of Volatile Organic Compounds in Andean Tomato Landraces by Headspace Solid Phase Microextraction-Gas Chromatography-Mass Spectrometry
Traditional tomatoes (Solanum lycopersicum L.) have been mainly selected for their fruit quality and maintained by local farmers in Andean areas of Cuyo and Northwestern Argentina. Volatile organic compounds (VOCs) in mature fruits of Andean tomato landraces were evaluated for the first time using headspace solid phase microextraction (HS-SPME) and gas chrom
J. Braz. Chem. Soc.. Publicado em: 2017-01
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34. Generation of Volatile Compounds from Carotenoids of Dunaliella bardawil Algae by Water Bath Heating and Microwave Irradiation
The volatile compounds formed by thermal degradation of the carotenoids present in Dunaliella bardawil were investigated by microwave irradiation (MW) and water bath heating (WB) in different conditions of temperature and time using central composite design. Volatiles extraction by solid phase microextraction (SPME) was optimized and performed at 40 °C for
J. Braz. Chem. Soc.. Publicado em: 2016-08
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35. EVALUACIÓN DE DES, FSC Y SPME/CG-MS PARA LA EXTRACCIÓN Y DETERMINACIÓN DE COMPUESTOS RESPONSABLES DEL AROMA DE CAFÉ TOSTADO DE VILCABAMBA - ECUADOR
The aim of this study was to compare the usefulness of three extraction methods: solid-phase microextraction (SPME) with four different coating (PDMS, PDMS/DVB, DVB/CAR/PDMS and PA), supercritical fluid extraction with carbon dioxide (SCF) and simultaneous distillation and extraction (SDE) for isolation of flavor compounds from roasted ground coffee (Coffea
Quím. Nova. Publicado em: 2016-07
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36. Optimization of the HS-SPME-GC/MS technique for the analysis of volatile compounds in caprine Coalho cheese using response surface methodology
Abstract Caprine Coalho cheese presents great potential for a typical protected designation of origin, considering that this traditional Brazilian cheese presents a slightly salty and acid flavor, combined with a unique texture. This study optimized the HS-SPME-GC-MS methodology for volatile analysis of Coalho cheese, which can be used as a tool to help in t
Food Sci. Technol. Publicado em: 01/04/2016