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Abstract  

EAEN (Advanced School of Nuclear Energy, 2010) is an annual school that consists of a week of activities in the area of Nuclear Physics, Radiochemistry and uses of Nuclear Energy for a public made of high school students. The EAEN project represents a pioneering program on science education and dissemination of knowledge, conducted by researchers and focused mainly on high school and scientific education for the population in general. The school’s priority is to explore the failures and the lack of education in the dissemination of nuclear energy for high school students as well as to attract prospective students with great potential for graduate courses of IPEN and other institutions in Sao Paulo and in Brazil.

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Abstract  

Instrumental neutron activation analysis (INAA) was used in the homogeneity study of a Perna perna (Linnaeus 1758) mussel reference material. Simultaneous determination of 15 elements in six bottles of the material, from a total of 171, was performed. The bottles were considered homogeneous for the analyzed elements, at the 95% confidence level, according to the analysis of variance test performed. Elements were also determined in one bottle with five different sample masses for minimum sample intake estimation. Results varied from 50 to 350 mg, depending on the element.

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Abstract  

Homogeneity study is one of the steps in reference material, RM, characterization. Due to its inherent characteristics, Instrumental Neutron Activation Analysis, INAA, is an analytical technique of choice for homogeneity testing. An interesting possibility is the use of complementary gamma ray photopeaks to confirm INAA homogeneity test results. In this study, the use of the complementary gamma ray photopeaks of 110mAg, 82Br, 60Co, 134Cs, 152Eu, 59Fe, 140La, 233Pa (for Th determination), 46Sc and 75Se radionuclides was investigated in the between bottle homogeneity study of a mussel candidate RM under preparation at IPEN–CNEN/SP. Although some photopeaks led to biased element content results, the use of complementary gamma ray photopeaks proved to be helpful in supporting homogeneity study conclusions for the new RM under characterization.

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Abstract  

Instrumental neutron activation analysis was used at a 2-month long isochronous short term stability test performed on a Perna perna mussel candidate reference material. The assessment of the analysis of variance test, as well as, the normalized results to the control temperature showed no systematic changes in the concentration of Ag, As, Br, Co, Cr, Cs, Fe, Eu, La, Na, Rb, Se, Sc, Th and Zn during the test period. The result showed that the candidate reference material may be transported under normal transport conditions without significant changes in composition for the determined elements.

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Abstract  

Arsenic and cadmium contents in eight edible mushroom species (Agaricus bisporus, Agaricus sp, Pleurotus ostreatus, Pleorotus florida, Pleorotus eryngui, Pleurotus osteatus, Pleurotus salmoneostramineus, Lentinula edodes) consumed by Brazilian population were determined by instrumental neutron activation analysis (INAA) and graphite furnace atomic absorption spectrometry (GF AAS), respectively. Arsenic concentrations varied from 0.009 mg/kg in P. eryngui to 0.210 mg/kg dry weight in L. edodoes and Cd from 0.011 g/kg in P. eryngui to 0.229 mg/kg dw in P. salmoneostramineus. The consumption of mushrooms in São Paulo-Brazil may be considered safe from a toxicological point of view as As and Cd presented levels of ingestion are below the maximum levels recommended by the World Health Organization.

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Abstract  

The increased pollution in the aquatic ecosystem has led to the investigation of toxic elements in sea water by using marine organisms to assess marine pollution from human activities. Among these organisms, the mollusks bivalves have been used as biomonitors since they can accumulate trace elements and other substances, without the occurrence of their death. In this study, Perna perna mussels were transplanted from a mussel farm (reference region) to four sites located in coastal regions of São Paulo State, Brazil, close to anthropic discharge areas. Vanadium was determined in mussel tissues by instrumental neutron activation analysis (INAA). Quality control of V analysis was checked by analyzing biological reference materials and the results obtained were precise and in good agreement with the certified values. Comparisons between the V concentrations obtained in transplanted mussels indicated that those from São Sebastião region, close to an oil terminal presented the highest concentration of this element, during spring.

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Abstract  

The Research Reactor Center (CRPQ) of IPEN/CNEN-SP operates the IEA-R1 Research Reactor, at a nominal power of 2 MW thermal, on a 64 hour per week continuous cycle. The IEA-R1 is a pool type reactor, moderated and cooled by light water, with graphite as a reflector. One of the main activities of CRPQ is the neutron activation analysis, which is applied to many fields of research, in collaboration with other institutes and universities. The Research Reactor installations are also intensely used for human resources development in the field of radiochemistry and neutron activation analysis, at graduate and post-graduate levels. In the present paper, an overview will be presented of some of the neutron activation analysis research lines that are being developed, comprising environmental and health-related applications.

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Summary  

The crude methanolic extracts of a single bean from samples of organic, natural or genetically modified (GM) soybeans [Glycine max. (Merrill) L.] were analyzed by direct infusion electrospray ionization mass spectrometry (ESI-MS). These extracts, containing the most polar natural products of soybeans (free aglycones, monoglucosides, diglucosides and esters including isoflavones and flavones) provide characteristic fingerprinting mass spectra owing to different proportions or sets of components. Spectra distinctiveness is confirmed by chemometric multivariate analysis of the ESI-MS data, which place the three-types of beans into well-defined groups. When ESI-MS is applied, these polar components constitute therefore unique chemotaxonomic markers able to provide fast soybean typification.

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Abstract  

Biomonitoring of coastal areas using marine organisms is an attractive approach for studying pollution caused by anthropic discharges. Most of the experiments are based on the collection and analysis of native organisms, but this method has the disadvantage of dealing with many natural variations. In this work, the marine bivalve Perna perna, very abundant in the coast of the State of São Paulo, Brazil, was transplanted from a mussel farm and used for biomonitoring of four sites, situated in coastal regions close to domestic and/or industrial discharges. Hg, Cd and Pb were determined in the transplanted organisms by AAS and As, Ca, Co, Cr, Fe, Na, Se and Zn were determined by INAA.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: M. Vasconcellos, P. Bode, G. Paletti, M. Catharino, A. Ammerlaan, M. Saiki, D. Fávaro, A. Byrne, R. Baruzzi, and D. Rodrigues

Abstract  

Biomonitoring of mercury contamination of Brazilian Indian population groups living in the Xingu Park, a reservation situated in the Amazonic region, has revealed very high levels of mercury in hair samples as compared to controls. Total mercury was determined by INAA in most of the tribes living in the Park and methylmercury was determined by CVAAS in samples with total mercury above 10 mg/kg. Due to the fact that selenium seems to protect animals against the toxic effects of methylmercury, it was considered also of interest to determine its concentrations in the hair samples with very high mercury levels. Selenium was determined by INAA via the short-lived radionuclide 77mSe (T 1/2 = 17.45 s). The correlations between selenium and mercury concentrations in Brazilian controls and in the Indian population groups are discussed.

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