Anthracene
Mostrando 25-36 de 232 artigos, teses e dissertações.
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25. Composition of carotenoids and anthocyanins from acerola : stability and antioxidant activity of anthocyaninc extracts from acerola and açai in model-systems. / Composição de carotenoides e antocianinas em acerola : estabilidade e atividade antioxidante em sistemas-modelo de extratos antocianicos de acerola e de açai.
Natural pigments, such as anthocyanins and carotenoids, are responsible for the colors found in foods, influencing its visual aspect, which is considered the main attribute for the acceptance and preference of a food product. At the same time, these pigments show important biological functions and actions, being considered human health promoters. The associa
Publicado em: 2006
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26. Fotodegradação de hidrocarbonetos policíclicos aromáticos em placas de sílica impregnadas com dióxido de titânio
Photodegradation of the PAHs anthracene, chrysene and benzo[k]fluoranthane on silica gel impregnated with TiO2 and over glass plates holding TiO2 was studied. Silica gel plates holding these substances were exposed to solar radiation, developed with hexane and photographed under ultra-violet light. The plates containing benzo[k]fluoranthene were also analyse
Química Nova. Publicado em: 2005-06
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27. Construction and the validation tests of an electronic device able to measure the half value layer in diagnostic X-ray beams / Construção de um dispositivo eletronico para determinação de camada semi-condutora em feixe de raios-x diagnostico
This work describes the construction and the validation tests of an electronic device able to measure the half value layer in diagnostic X-ray beams. The device utilizes a transducer assembled with three sensors using the photoluminescence of the organic scintillator anthracene. The light signal, proportional to the incident radiation, reaches three photo re
Publicado em: 2005
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28. Tomato and garlic by gavage modulate 7,12-dimethylbenz[a]anthracene-induced genotoxicity and oxidative stress in mice
Chemoprotection by dietary agents is a promising strategy for cancer prevention. The aim of the present study was to evaluate the combined effect of tomato and garlic against 7,12-dimethylbenz- [a]anthracene (DMBA)-induced genetic damage and oxidative stress in 12-14-week-old male Swiss albino mice. The animals were randomized into experimental and control g
Brazilian Journal of Medical and Biological Research. Publicado em: 2004-07
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29. Modelagem do equilibrio de fases em misturas de dioxido de carbono supercritico e compostos presentes em produtos naturais / Phase equilibria modeling of mixtures of supercritical carbon dioxide and compounds present in natural products
Modeling and simulation of supercritical extraction processes request a good prediction of conditions of phase equilibrium, conditions that determine the higher concentration of liquid or solid (solute) to be extracted by supercritical fluid (solvent). The main problem in modeling of systems found in supercritica1 extraction processes is the great size diffe
Publicado em: 2002
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30. Hidrocarbonetos policiclicos aromaticos em oleo de milho, margarina, creme vegetal e maionese e efeito do processamento na contaminação
In the present study, the contamination by benzo(a)pyrene B(a)P of corn oils produced and marketed in Brazil was monitored. The effect of the drying and grinding processes of the corn , and the refining process of the crude oil on the contamination of the refined oil was also studied. Besides, eight polycyclic aromatic hydrocarbons (PAHs) were determined in
Publicado em: 1998
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31. Aplicação de silica, contendo o grupo etilenodiamina ancorado, como fase estacionaria para CLAE
ln the present work, chromatographic silica was chemically modified with the silylant agent: [3-(2-aminoethyl)aminopropyl]trimethoxysilane (AEAPTS). After this reaction, the residual silanol groups were deactivated with chlorotrimethylsilane. These silicas were reacted with copper ions in a methanol medium. This cation was strongly adsorbed through complexat
Publicado em: 1998
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32. Espectroscopia eletronica aplicada ao estudo de relaxações de polimeros estirados
The relaxations of low density polyethylene (LDPE) and poly(vinyl acetate) PVAc have been probed by luminescence spectroscopy of anthracene (fluorescent) molecules dissolved (or covalently linked to) in the polymeric matrix. The LDPE sample has been studied in two ways: unstretched, and 500% uniaxially stretched; The stretched films were analysed with both,
Publicado em: 1995
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33. Aplicação da microscopia otica de fluorescencia ao estudo de polimeros e blendas polimericas de PVA/PVAc
A morphological study of polymer blends of 87-89% hydrolized PVA (124.000-186.000) and PVAc (high molecular weight) has been made using the relative compositions 9:1, 1:1 and 1:9, containing fluorescein (0,1% m/m). The formation of two phases, from a process of liquid-solid phase separation has been observed during the solvent(ethanol/water) evaporation The
Publicado em: 1994
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34. Sintese e algumas propriedades de oligo e polissilarilenos
In this work several oligo- and poli-p-silphenylenes containing SiMe2 or SiPh2 groups, alternated whith p-phenylenes units in the main chain, were synthetized. The olygomers and polymers were sinthetized from organic substrates with varied reactivities and solvents with different coordination ability via di-Gignard intermidiates. Poly-p-silphenylenes was als
Publicado em: 1991
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35. Estudo das relaxações de polimeros utilizando sondas luminescentes
Some relaxations of organic polymers were studied using luminescence probes dispersed in the polymers. We have studied the following polymers: poly(styrene), poly(vinyl acetate), poly(propylene), low density poly(ethylene) and poly(ethylene glycol)-600. Anthracene and benzophenone were dispersed in these polymers to analyse the temperature dependence on both
Publicado em: 1988
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36. Metabolic pathways of 7,12-dimethylbenz[a]anthracene in hepatic microsomes.
High pressure liquid chromatography has enabled quantitative analysis of the in vitro metabolism of 7,12-dimethylbenz[a]anthracene, 7-methyl-12-hydroxymethylbenz[a]anthracene, 7-hydroxymethyl-12-methylbenz[a]anthracene, and 7,12-dihydroxymethylbenz[a]anthracene by 3-methylcholanthrene-induced and control rat liver microsomes. The following previously unrecog