Volatiles
Mostrando 1-12 de 195 artigos, teses e dissertações.
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1. Processamento de catalisadores gastos de unidade de hidrodessulfurização profunda (ultra-deep HDS)
PROCESSING OF SPENT ULTRA-DEEP HYDRODESULFURIZATION CATALYSTS. This work discusses the recycling of spent NiMo/Al2O3 catalysts from ultra-deep hydrodesulfurization (HDS) units. They contain a refractory coke and fouling elements from the processed feedstocks. Samples were preoxidized (600 ºC) for 12 h using a very slow heating rate to eliminate coke and vol
Química Nova. Publicado em: 2022
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2. Thermal and Catalytic Fast Pyrolysis of Oily Extracts of Microalgae: Production of Biokerosene
Three different microalgae species, Desmodesmus sp., Nannochloropsis oculata and Halamphora coffeaeformis were grown under controlled conditions. The resulting dry biomass was characterized by TG-DTA (thermogravimetry-differential thermal analysis) and extracted with three solvents having different polarities. The extracts gross mass yields varied from 2% us
J. Braz. Chem. Soc.. Publicado em: 2021-04
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3. OTIMIZAÇÃO DO PROCESSO NÃO INVASIVO E NÃO DESTRUTIVO DE EXTRAÇÃO E ANÁLISE DE METABÓLITOS VOLÁTEIS DE MAMÃO PAPAIA POR SPME-GC-MS
The analysis of volatiles is an alternative in the routine of quality control of fruits, since the volatile metabolites can change in the presence of microorganisms. A well-established method for extracting volatiles is the solid phase microextraction (SPME). This work aims to define some parameters (fiber coating, conditioning time and fiber exposure time)
Quím. Nova. Publicado em: 2020-09
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4. VOLATILE COMPOUNDS IN CACHAÇAS OBTAINED FROM THREE SUGARCANE VARIETIES CULTIVATED UNDER THE MANAGEMENTS: ORGANIC, CONVENTIONAL AND WITHOUT FERTILIZATION
The volatile compounds present in cachaça can derive from the raw material used in the production of the beverage, from the fermentative process, from distillation or aging. The aim of the research was to evaluate the volatile compounds, in the cachaças from stills produced with different sugarcane varieties, under the organic and conventional managements.
Quím. Nova. Publicado em: 2020-09
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5. Effects of Soil and Vineyard Characteristics on Volatile, Phenolic Composition and Sensory Profile of Cabernet Sauvignon Wines of Campanha Gaúcha
The influence of vineyard on wines was evaluated for the first time using a broader analytical approach: sensory analyses and several analytical techniques (gas chromatography-mass spectrometry (GC-MS), GC flame ionization detection (FID), GC-olfactometry-Osme technique (GC-O-Osme), GC × GC-MS), taking into account odoriferous compounds of Cabernet Sauvigno
J. Braz. Chem. Soc.. Publicado em: 2020-06
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6. Characterization of volatiles in red- and white-fleshed loquat (Eriobotrya japonica) fruits by electronic nose and headspace solid-phase microextraction with gas chromatography-mass spectrometry
Abstract Aroma differences are generally sensed in white- and red-fleshed loquats. Here, volatile compounds in four white- and three red-fleshed loquat varieties were investigated by headspace solid-phase microextraction and combined analysis of electronic nose (e-nose) and gas chromatography-mass spectrometry (GC-MS). In total, 83 volatile compounds were id
Food Sci. Technol. Publicado em: 2020-06
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7. Preference of Neoseiulus californicus (Acari: Phytoseiidae) for volatiles of Bt maize induced by multiple herbivory
ABSTRACT Plant indirect induced defenses against herbivores are characterized by the production of plant volatiles that to attract natural enemies. The objective of this study was to evaluate whether the attack of the two-spotted spider mite Tetranychus urticae or the multiple herbivory of T. urticae together with the fall armyworm Spodoptera frugiperda are
Rev. Bras. entomol.. Publicado em: 13/01/2020
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8. UM CONJUNTO DE PLANILHAS ELETRÔNICAS PARA IDENTIFICAÇÃO E QUANTIFICAÇÃO DE CONSTITUINTES DE ÓLEOS ESSENCIAIS
The identification of essential oils constituents has been made easier and faster by the use of automatic software search engines that compare the experimental mass spectra and calculate the retention indices with those in commercial databases. However, these search engines and databases are very expensive. Electronic sheets have been assembled in a set of l
Quím. Nova. Publicado em: 2020-01
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9. Petiveria alliacea, a plant used in Afro-Brazilian smoke rituals, triggers pulmonary inflammation in rats
Abstract Petiveria alliacea L., Phytolaccaceae, a plant used in Afro-Brazilian religious smoke rituals is reported to have "harmonic properties" (anxiolytic effect) by ethnobotanical survey. In the present work, we analyzed the chemical composition of volatiles produced by leaves of P. alliacea, using headspace gas chromatography/mass spectrometry and its po
Rev. bras. farmacogn.. Publicado em: 09/12/2019
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10. Quality of olive oils from southeastern Brazil
ABSTRACT This study aimed to characterize the volatile composition and sensory characteristics of virgin olive oils (VOOs) from eight olive cultivars grown in the southeast region of Brazil. The volatiles were extracted by Solid Phase Micro Extraction (SPME) and analyzed by Gas Chromatography coupled to MassSpectrometry (GC-MS). The dominant sensory attribut
Bragantia. Publicado em: 04/11/2019
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11. QUÍMICA DO LÚPULO
Hops in the brewing process are important for the chemical and sensorial quality of beer. Hops give to the beer bitterness (due to the presence of humulones and lupulones), natural antioxidants (due to the presence of polyphenols) and flavor (due to the presence of volatiles and essential oils). In this paper, we present, for the first time in Portuguese, a
Quím. Nova. Publicado em: 21/10/2019
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12. Óleos essenciais no controle de Botrytis cinerea: influência na qualidade pós-colheita de uvas ‘Rubi’
Resumo Para que ocorra o controle de doenças na pós-colheita de uvas, são utilizados agroquímicos que, apesar de eficientes, podem causar problemas à saúde humana. Neste sentido, o presente trabalho tem o objetivo de verificar o potencial dos compostos voláteis presentes no óleo essencial de pitanga (OEP), guaçatonga (OEG) e melaleuca (OEM) no contr
Braz. J. Food Technol.. Publicado em: 17/10/2019