FABIO RODRIGO PIOVEZANI ROCHA
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Artigo IPEN-doc 24729 Metal and trace element assessments of bottom sediments from medium Tietê River basin, Sao Paulo State, Brazil: part II2018 - FAVARO, D.I.T.; ROCHA, F.R.; ANGELINI, M.; HENRIQUES, H.R.A.; SOARES, J.S.; SILVA, P.S.C.; OLIVEIRA, S.M.B.Concentration of metals in 15 bottom sediment samples from Tieteˆ River, a significantly polluted river, were assessed. Total and partial trace element concentrations were determined, and As, Cd, Cr, Cu, Ni and Zn were found above local reference values. These metals were also higher than the threshold effect level (TEL) in some sampling points and Zn was higher than probable effect level (PEL) oriented values in almost all sampling points. The most polluted points were identified from Tieteˆ to Barra Bonita Counties. Regarding sediment quality, this river is still polluted and precautions to minimize environmental problems caused by toxic metals to biota and to human health are necessary.Resumo IPEN-doc 24620 Natural and artificial nuclides in Salesópolis reservoir by gamma spectometry2017 - SILVA, P.S.C.; SEMMLER, R.; ZAHN, G.; ROCHA, F.R.; DAMATTO, S.R.; FAVARO, D.I.T.Natural radioactivity is ubiquitous in the environment mainly due to the presence of the nuclides from the uranium and thorium series and K-40 in soil, water and sediments. Although in the South Hemisphere nuclear tests have been fewer in number than that in the North, artificial radionuclides can also be found spread at ground level. Salesópolis is located in the Metropolitan Region of São Paulo city (SPMR). The Usina Parque Rio Tietê (Salesópolis) reservoir belong to the Alto do Tietê system for the capture, storage and treatment of water for the São Paulo Metropolitan Region (SPMR). Therefore, the quality of the water, as well as, of sediments of this dam is of great importance. In this study, the activity concentrations of the natural uranium and thorium nuclides series, K-40 and the artificial Cs-137 were determined in a sediment core (T1B) with 42cm depth and sliced each 3 cm totalizing 14 samples, collected in the middle of the Salesópolis dam. Samples were sealed and wait 30 days for the radioactive equilibrium to be reached. The activity concentrations were measured by gamma spectrometry. Samples were counted and saved at regular intervals at a maximum of 160 000 seconds. The gross area were calculated for each peak and plotted against time and the counting rate was obtained by the sloop of the curve. The background and reference materials were treated in the same way. Results showed that 228Th varied from 44 to 150 Bq kg1 ; 228Ra, from 49 to 149 Bq kg1; 226Ra, from 26 to 88 Bq kg1; 210Pb, from 93 to 247 Bq kg1 ; 40K, from 127 to 852 Bq kg1 and 137Cs varied from 0.2 to 6.7 Bq kg1Artigo IPEN-doc 21296 NAA and XRF technique bottom sediment assessment for major and trace elements: Tiete River, São Paulo state, Brazil2015 - ROCHA, F.R.; SILVA, P.S.C.; CASTRO, L.M.; BORDON, I.C.C.L.; OLIVEIRA, S.M.B.; FAVARO, D.I.T.