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Search Results: 1 - 10 of 399757 matches for " Antonio Carlos S. Fernandes "
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Chemotaxonomical aspects of lower Cretaceous amber from Rec?ncavo Basin, Brazil
Pereira, Ricardo;Carvalho, Ismar S.;Fernandes, Antonio Carlos S.;Azevedo, Débora A.;
Journal of the Brazilian Chemical Society , 2011, DOI: 10.1590/S0103-50532011000800015
Abstract: the chemical composition of lower cretaceous amber samples from rec?ncavo basin (salvador, bahia) was performed by gc-ms to characterize possible botanical sources. the compounds identified were hydrocarbonic and polar diterpenoids, such as abietane, dehydroabietane, tetrahydroretene, dehydroabietol, dehydroabietic acid, ferruginol and sugiol. other diterpenoid classes were not detected as well as triterpenoids. the composition of the extracts and chemosystematic data allows relating the samples to conifers of podocarpaceae or cheirolepidiaceae families due to detection of ferruginol, a specific biomarker to these families. the data concerning cretaceous amber in the rec?ncavo basin provided information concerning the presence of a resinous flora in the maracangalha formation sediments during the lower cretaceous.
Molecular composition, chemotaxonomical aspects and botanical origin of Brazilian amber [Composi o molecular, aspectos quimiotaxon micos e origem botanica de ambares brasileiros]
Ricardo Pereira,Ismar S. Carvalho,Antonio Carlos S. Fernandes,Débora A. Azevedo
Revista Virtual de Química , 2011,
Abstract: Amber is a plant fossil resin constituted mainly by diterpenes of several classes, such as abietanes, labdanes, pimaranes and kauranes. The botanical origin of amber is related to angiosperms and gymnosperms, depending on the geological period and where it was produced. The analysis of its chemical composition performed using gas chromatography coupled to mass spectrometry and carbon 13 nuclear magnetic resonance allows the determination of the possible botanical sources, allowing obtaining important information regarding the resinous flora on the geological past of the Earth. Although amber samples are studied primarily by geochemists and paleontologists in the context of paleobotany and paleozoology, the research about its molecular composition is directly related to chemotaxonomy and phytochemistry. The results obtained to Brazilian amber samples until this moment allowed the determination of three possible amber botanical sources in Cretaceous period – Araucariaceae, Podocarpaceae e Cheirolepidiaceae.
Avalia??o dos riscos ocupacionais de trabalhadores de servi?os de radiologia
Fernandes, Geraldo Sérgio;Carvalho, Antonio Carlos Pires;Azevedo, Ana Cecília Pedrosa de;
Radiologia Brasileira , 2005, DOI: 10.1590/S0100-39842005000400009
Abstract: objective: to evaluate the biosafety aspects and the working conditions of radiology department professionals and to make recommendations with respect to necessary modifications to be implemented in these departments in order to comply with national regulations. materials and methods: interviews with the professionals were carried out as well as observation of their activities in the working premises including processing of radiographic films inside the dark rooms, average time inside the dark rooms, preparation of chemical solutions for automatic processors and the type of help given to patients during radiographic examinations. the efficiency of the exhausting systems in the dark rooms was also measured. the ergonomic adequacy of the accessories inside the dark rooms was analyzed. with respect to electrical safety, the location and number of fire extinguishers as well as the grounding of the electrical equipment was evaluated to check if they were in accordance with the brazilian legislation. results: the exhaustion systems were insufficient, professionals did not wear protective clothes/devices when preparing the chemical solutions, the ergonomic aspects were not in accordance with national recommendations, and the workers presented related stress. conclusion: based on these results, risk maps were drawn for each sector of the radiology department to be used in the implementation of improvements in each sector.
Minera o versus Paleontologia: Uso e Ocupa o da Serra do Veadinho em Peirópolis - Uberaba, Estado de Minas Gerais (Brasil)
Wellington Francisco Sá dos Santos,Ismar de Souza Carvalho,Antonio Carlos Sequeira Fernandes
Anuário do Instituto de Geociências , 2010,
Abstract: Peirópolis é um bairro do município de Uberaba (Estado de Minas Gerais) que possui um extraordinário sítio paleontológico do Cretáceo Superior, rico em fósseis de vertebrados, destacando-se os dinossauros. A maioria dos fósseis tem sido encontrada em arenitos na serra do Veadinho. Entretanto, abaixo dos arenitos existe uma camada de calcário que foi explorada economicamente pela atividade mineradora de imigrantes europeus entre 1890 e 1960. Nesse período, a minera o realizou-se com técnicas manuais de extra o contribuindo com a descoberta dos fósseis. No entanto, no ano de 1987, a minera o passou a ser exercida através de técnicas mecanizadas de extra o, gerando impactos ambientais e destrui o dos fósseis. Assim, iniciou-se uma disputa judicial pelo uso e ocupa o da área entre a minera o, a popula o local e geocientistas. Atualmente o lugar é de uso exclusivo para pesquisas paleontológicas e futuramente atividades turísticas. Nesse contexto, realizou-se um resgate histórico da disputa pelo uso e ocupa o da serra do Veadinho, entre 1987 e 1992, para se analisar a compatibiliza o entre a minera o e as pesquisas paleontológicas.
GRUPOS DE PERMUTA ES E GRUPOS FINITOS SIMPLES
Lauro Maycon Fernandes Ferreira,Antonio Carlos Tamarozzi,S?nia Angelina Garcia Modesto
Colloquium Exactarum , 2011, DOI: 10.5747/ce.2011.v03.n1.e027
Abstract: The normality of subgroups in a finite group has a property discovered by E. Galois in 1832, study-group of permutations of roots of polynomial equations. Since then, this concept was explored extensively by adding definitions and properties that contributed to the description of various concepts of impact on the structure of finite groups. This paper presents an introductory development of group theory of permutations, in order to present examples of simple groups. This research has provided important technical contact for the development of group theory, based on normal subgroups, centralizers,class equation, p-groups and Sylow first theorem.
Cimenta o adesiva – Revis o de literatura
Sérgio Ricardo Garcia Badini,Antonio Carlos da Silva Tavares,Marco Antonio de Lima Guerra,Nivio Fernandes Dias
Odonto , 2008,
Abstract: Através de uma revis o de literatura procurou-se descrever sobre a cimenta o adesiva de restaura es indiretas estéticas e livres de metal, em compara o com os demais agentes cimentantes. Com base nas informa es obtidas chegou-se à conclus o que a cimenta o adesiva é de fundamental importancia quando se trata de restaura es metal free.
Solid state 13C NMR analysis of Brazilian cretaceous ambers
Pereira, Ricardo;San Gil, Rosane A. S.;Carvalho, Ismar S.;Fernandes, Antonio Carlos S.;Azevedo, Débora A.;
Journal of the Brazilian Chemical Society , 2011, DOI: 10.1590/S0103-50532011000100012
Abstract: 13c cross polarization with magic angle spinning nuclear magnetic resonance (13c cpmas nmr) spectra have been obtained for the first time to three cretaceous amber samples from south america. the samples were dated to lower cretaceous and collected in sediments from the amazonas, araripe and rec?ncavo basins, brazil. all samples have very similar spectra, consistent with a common palaeobotanical source. some aspects of the spectra suggest a relationship between brazilian ambers and araucariaceae family, such as intense resonances at 38-39 ppm. all samples are constituted by polylabdane structure associated to class ib resins, constituted by polymers of labdanoid diterpenes. finally, information concerning some structural changes during maturation, such as isomerization of δ8(17) and δ12(13) unsaturations, were obtained by 13c nmr analyses. the results concerning botanical affinities are in accordance with previous results obtained by gas chromatography-mass spectrometry (gc-ms).
Fósseis: Mitos e Folclore
Antonio Carlos Sequeira Fernandes
Anuário do Instituto de Geociências , 2005,
Abstract: Fossils have been familiar objects to man since the prehistoric times, with striking connotations in the folklore of several cultures. They were used as decorative elements in necklaces, regarded as heroes or giants in the classical greek and roman times, interpreted as teeth and bones of dragons, used as amulets against the bites and poisons of snakes, and as medicines to the treatment of several disorders. This article describes some of these examples.
Análise e gerenciamento de efluentes de servi?os de radiologia
Fernandes, Geraldo Sérgio;Azevedo, Ana Cecília Pedrosa de;Carvalho, Antonio Carlos Pires;Pinto, Maria Lucia Couto;
Radiologia Brasileira , 2005, DOI: 10.1590/S0100-39842005000500009
Abstract: objective: with the aim of reducing and preventing environmental damages, handling and disposing practices of chemical effluents from radiology departments were investigated and a service management model was created in order to obtain financial resources for the department. materials and methods: the proposed model, based on the evaluation of chemical effluents from automatic processors of radiographic films, showed that fixer reprocessing can be an adequate choice to solve environmental and financial problems in these departments. this model also emphasizes that compliance with management guidelines should be observed, i.e. other effluents (developer and water) must be chemically treated before disposal in the natural environment. the economical analysis has confirmed that the income originated from commercializing the silver (of which concentration ranges from 3.5 to 10.2 g/l), recovered from the used fixer, in addition to the income from the reuse of the fixer (after its recovery), is in the worst scenario (when the silver concentration is 3.5 g/l) enough to cover all the expenses with the implementation of the project. conclusion: the proposed model can be a good choice for solution of environmental and financial problems. moreover, it is ecologically correct, a potential source of financial resources to radiology departments, and can be applied to other institutions due to the similarity of problems and resources.
A??o do biofertilizante Agrobio sobre a mancha-bacteriana e desenvolvimento de mudas de piment?o
Deleito, Cláudia S.R.;Carmo, Margarida Goréte F. do;Fernandes, Maria do Carmo de A.;Abboud, Antonio Carlos de S.;
Horticultura Brasileira , 2005, DOI: 10.1590/S0102-05362005000100025
Abstract: the agrobio biofertilizer is prepared from fresh cattle manure, water, molasses and minerals in open containers. this product has been widely used by organic and conventional farmers of the rio de janeiro state to control several plant pathogens. this research aimed to elucidate and quantify some of the aspects related to the beneficial effect of agrobio on bell pepper (capsicum annuum l.) transplants under greenhouse conditions. two cultivars, 'cascadura ikeda' and 'cascadura itaipu' were used. four agrobio treatments, all diluted 5% (v/v) in distilled water were used. they consisted of: (a) raw; (b) autoclaved (120oc/20 min); (c) filtered in millipore (0,22 μ diameter) and (d) the fraction retained on the millipore. they were applied as foliage sprays or directly on the substrate. as control treatments, oxytetracicline + streptomycin sulphate (0.8 g l-1), copper oxichloride (2.4 g l-1) and water were used. raw of filtered agrobio, as a foliage spray, resulted in better control of the disease and higher growth of the transplants, compared to autoclaved and fraction retained of the agrobio and substrate sprays. all agrobio treatments resulted in a less satisfactory disease control when compared to the commercial products, copper oxichloride and oxitetracicline + streptomycin sulphate, but more, effective than water. agrobio stimulated the vegetative growth of the transplants, reduced the incidence of bacterial spot, increased the leaf area and promoted a better retention of infected leaves and the bacillus spp. population.
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