J.O. SANTOS

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Agora exibindo 1 - 10 de 21
  • Resumo IPEN-doc 14443
    INAA: A link between past and present in retrieving of peoples identities
    2007 - MUNITA, C.S.; SANTOS, J.O.; TOYOTA, R.G.; NUNES, K.P.; OLIVEIRA, P.M.S.; FERREIRA, D.S.
  • Resumo IPEN-doc 10033
    Geostatistical mapping of the concentration of Zn in the Bay of Sepetiba in Rio de Janeiro, Brazil
    2004 - RIBEIRO, A.P.; FIGUEIREDO, A.M.G.; WASSERMAN, J.C.; SANTOS, J.O.
    In general, the growth of the economical activities in a country is directly conelated to the increase of pressure on natural systems, leading several authorities and specialists to the discussion of the impacts generated and the main actions to minimize them. Over the last years, such discussions have established new paradigms in the means of production in terms of sustainable growth and preservation of natural resources for future generations. In particular, the concern with the water systems has been great, since those are the ones that are most affected by industrial and domestic activities. Within this confext, this study will approach the contamination with Zn of the Bay of Sepetiba, located in the state of Rio de Janeiro, in the southwest region of Brazil. As a result of the industrial and urban expansion over the last three decades, the region has been rather impacted, particularly with the contamination with Zn, as it has been recorded by several authors. With the purpose of assessing precisely the human action concerning the Zn in the region, the concentrations of this metal were determined by instrumental neutron activation analysis (INAA) in 60 samples geographically referred in a regular network. The distribution and evaluation of the risks due to the contamination with Zn in Sepetiba were investigated through classic statistical techniques and geostatistics. In order to limit the effects of discrepant values and later geostatistical analysis, the data were normalized through a Box-Cox transformation. The parameters of the spatial disfribution of the concentrations of Zn were estimated through the adjustment from the theoretical to the experimental variogram via method of the minimum pondered squares. The mapping of the concentrations of the metal studied in this work was carried out through ordinary kriging. In order to evaluate the quality of the geostatistical analysis, the prection variances maps was designed and the cross-validation was carried out. Aiming at identifying the most critical areas with regards to the confamination with Zn, it was constructed the map of probability of concentration that exceed the contents found in the regions that did not undergo human influence. The results obtained in this study provide precise information to evaluate the risks posed by high concentrations of Znin the Bay of Sepetiba, with the purpose of aiding the authorities in their decisions to effectively control the problem.
  • Resumo IPEN-doc 10401
    Mobility of zinc in sediments from Sepetiba bay, Rio de Janeiro
    2005 - RIBEIRO, A.P.; FIGUEIREDO, A.M.G.; WASSERMANN, J.C.; SANTOS, J.O.
  • Resumo IPEN-doc 18962
    Concentration attenuation model to assess arsenic, antimony, chromium, selenium and zinc mobility in sediments from Sepetiba Bay, Rio de Janeiro
    2008 - RIBEIRO, A.P.; FIGUEIREDO, A.M.G.; SANTOS, J.O.; WASSERMAN, J.C.
    This study proposes a new geostatistical approach for the determination of the mobility of As, Cr, Sb, Se and Zn in sediments based on spatial distribution. The sediment samples were collected from the Sepetiba Bay, Rio de Janeiro, Brazil. The Sepetiba region plays an important role to the economy of Brazil, due to its metallurgical industries and of the Itaguai Harbor. This bay is an example of an aquatic system that has been suffering from severe impact by human occupation and industrial activity in its basin. Total concentrations were determined by using Instrumental Neutron Activation Analysis. The results obtained showed that As, Cr and Se presented higher concentrations close to the Itacuruçá Island (northwest), a region where tourism and small shipyard activities are important. Sb presented a homogeneous distribution along the entire bay. Zn, on the other hand, presented higher concentrations in the northeastern area, close to the mouth of Guandu and Canal de São Francisco rivers, responsible for 95% of the input of fluvial water in the bay. These rivers receive industrial wastes from the industrial park, at about 3 km from the coast. The geostatistical approach (concentration attenuation model) showed that the highest attenuation values for the elements studied are at the same sites where the highest total concentrations were observed. This indicates low mobility of these elements in the Sepetiba bay.
  • Resumo IPEN-doc 18960
    Chemical and mineralogical characterization of archaeological ceramics from Xingó
    2008 - SANTOS, J.O.; MUNITA, C.S.; OLIVEIRA, P.M.S.; VERGNE, C.; TOYOTA, M.
  • Resumo IPEN-doc 13660
    Evaluation of mercury and selenium accumulation in fish consumed by Cananeia community, Sao Paulo, Brazil
    2008 - FARIAS, L.A.; FAVARO, D.I.T.; CURCHO, M.; NASCIMENTO, S.M.; SANTOS, J.O.; AZEVEDO, J.S.; BRAGA, E.S.
  • Artigo IPEN-doc 13990
    Normalizacao e padronizacao por meio da transformacao logaritmica em estudos arqueometricos de ceramicas
    2007 - SANTOS, J.O.; MUNITA, C.S.; VERGNE, C.; OLIVEIRA, P.M.S.
  • Artigo IPEN-doc 13994
    Archaeological sites from baixo Sao Francisco, Brazil: Archaeometric approach on Justino site
    2007 - SANTOS, J.O.; MUNITA, C.S.; VALERIO, M.E.G.; VERGNE, C.
  • Artigo IPEN-doc 10656
    Avaliacao da mobilidade de metais e semi-metais em sedimentos coletados em diferentes periodos na Baia de Sepetiba (Rio de Janeiro - Brasil)
    2005 - CORTEZ, V.D.; RIBEIRO, A.P.; FIGUEIREDO, A.M.G.; SANTOS, J.O.; WASSERMANN, J.C.
  • Artigo IPEN-doc 12047
    Application of INAA to provenance study of ceremics from baixo Sao Francisco River, Sergipe, Brazil
    2007 - MUNITA, C.S.; SANTOS, J.O.; VERGNE, C.; TOYOTA, ROSIMEIRI G.