1000 resultados para Viticultura brasileira
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This paper describes a comparative analysis on natural product chemistry between the Brazilian Chemical Society journals and twelve representative international publications in the area. The search using the ISI Web of Knowledge disclosed 41,362 publications in the years 2000-2002 containing at least one researcher from a Brazilian Institution, from which 12% belongs to natural products.
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The monitoring of the pollution status of the Brazilian coast is hampered by the lack of a consistent environmental indicator. We propose Hg as an environmental proxy to anthropogenic pollution of coastal regions due to its absence in the Brazilian geology, its ubiquity in anthropogenic effluents, and its toxicity. Available data suggest Hg "backgrounds" in coastal sediments of 1-10 ng g-1, in the East and 15-30 ng g-1 in the South. We suggest short sediment cores to establish these values estimating a geo-accumulation index to compare all areas. The distribution of index values showed the majority of southern coast at least moderately contaminated whereas many eastern areas are still pristine.
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Montmorillonite clay from Brazil was pillared with aluminium polyhydroxications. The influence of aging of the pillaring solution and the concentration of the clay suspension on the properties of the prepared materials was studied. The materials were characterized by chemical analysis, XRD and pore analysis by N2 adsorption. The catalytic properties were evaluated in the cumene cracking reaction. Results showed that the pillarization process increases the basal spaces of natural clay from 9.7 to 18.5 Å and the surface area from 41 to 300 m²/g.
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Phosphorus geochemistry as a proxy of environmental estuarine processes at the Jaguaribe River, Northeastern Brazil. Sedimentation of different phosphorus geochemical fractions can characterize the natural or anthropogenic processes dominant in the watershed. Selective chemical extraction of different phosphorus geochemical forms in estuarine sediments showed the predominance of inorganic over organic forms suggesting an increase in inorganic phosphorus input from anthropogenic sources. Local hydrochemistry favors the dominance of inorganic ferric and carbonatic phosphorus. Ongoing changes in the estuarine throphy, from mesothrophic to euthrophic, may decrease the immobilization of these forms, increasing dissolved phosphorus and favoring euthrophy. Detritic phosphorus suggests a fluvial origin of this fraction and acts as a tracer of river influence upon the estuary.
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This article offers an overview on the historical facts and the recent state of the Regional Secretaries and the Scientific Divisions in the course of 30 years of SBQ.
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This paper presents some aspects involved in the internationalization of SBQ. The importance of journals, meetings and agreements in this process is discussed.
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The main aspects of the modern Medicinal Chemistry, among the classic and industrial paradigms, used in the drug discovery process will be treated. The contribution of the Brazilian science in the knowledge generation in Medicinal Chemistry will be demonstrated, with base in searches accomplished in the portal Web of Science® 7.10 and in the directory of groups of research of CNPq.
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Higher education was precariously installed in Brazil in colonial times, and during that period it led a difficult life. From the early nineteenth century on several institutions were founded and developed in different parts of the country. Those institutions were kept independent from one another without forming full universities until the beginning of the twentieth century, in a peculiar historical process that sets the country apart in this respect. This article examines this unique development and searches the past for the earliest origins of the nation's present university network.
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This paper discusses the Brazilian academic production on Chemical Education. The main source of information is the annual meeting of the Brazilian Chemical Society (RASBQ) covering the period 1999-2006. All the papers presented by the Division of Chemical Education of the RASBQ were reviewed to permit a discussion about the development of the area in Brazil. This bibliographical revision comprises the following aspects: year of presentation, Brazilian region and institution of production, scholastic level encompassed by the study, the kind of academic work (or research type) and thematic focus of the study.
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This paper discusses of the use of the Impact Factor in the evaluation of chemistry graduate courses by CAPES and the internationalization of the Journal of the Brazilian Chemical Society and Química Nova.
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A brief comment about general characteristics of polysaccharide was presented. Brazilian trade of polysaccharides was obtained from the "Ministério de Desenvolvimento, Indústria e Comércio Exterior" - Brazil. A list of these products was prepared and their price and amount analyzed in the period of 1998-2007. Some chemical properties and application of polysaccharides from our biodiversity was described. In this review they were classified by origin, in vegetal (exudate, seed, fruit, seaweed), animal and bacteria source. There is a trade deficit that can be reverted if part of the accumulated scientific knowledge was used to promote the national economic development in the field.