SANDRA REGINA DAMATTO

SANDRA REGINA DAMATTO

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Natural and artificial nuclides in Salesópolis reservoir
2019 - SILVA, P.S.C.; SEMMLER, R.; ZAHN, G.S.; 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 ura-nium and thorium series and 40K. 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. In this study, the activity concentrations of natural nuclides from the uranium and thorium series, 40K and the artificial 137Cs were deter-mined in a sediment core with 42 cm depth collected in the middle of the Salesópolis reservoir, located in the Metropolitan Region of São Paulo city (SPMR). The Usina Parque Rio Tietê reservoir belongs to the Alto do Tietê system for the capture, storage and treatment of water for SPMR. Therefore, the quality of the water and sediments of this dam is of great importance. The activity concentrations were measured by gamma spectrome-try. Samples were measured and saved at regular intervals at a maximum of 160 000 seconds. The gross area were determined for each peak and plotted against time and the counting rate was obtained by the slope of the curve. Background and reference materials were also counted and treated in the same way. Results showed that 226Ra varied from 45 to 116 Bq kg-1; 228Ra, from 80 to 165 Bq kg-1; 40K, from 155 to 1 187 Bq kg-1 and 137Cs varied from 0.3 to 7 Bq kg-1. The methodology applied for determining low levels of 137Cs in sediment proved to be effi-cient and reproducible.
Natural and artificial nuclides in Salesópolis reservoir by gamma spectometry
2017 - 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 kg􀀀1 ; 228Ra, from 49 to 149 Bq kg􀀀1; 226Ra, from 26 to 88 Bq kg􀀀1; 210Pb, from 93 to 247 Bq kg􀀀1 ; 40K, from 127 to 852 Bq kg􀀀1 and 137Cs varied from 0.2 to 6.7 Bq kg􀀀1
Natural and artificial nuclides in Salesópolis reservoir by gamma spectrometry
2017 - SILVA, PAULO S.C.; SEMMLER, RENATO; ZAHN, GUILHERME S.; ROCHA, FLAVIO R.; DAMATTO, SANDRA R.; FAVARO, DEBORAH I.T.
Historical accumulation of trace elements in sediment cores from Tiete river, São Paulo, Brazil
2014 - DAMATTO, S.; ROCHA, F.; BAUMGARDT, D.; MARTINS, L.; SILVA, P.; FAVARO, D.
Trace elements by neutron activation analysis in three sediments cores from the Alto Tietê River sub-basin, São Paulo-Brazil, dated by 210Pb method
2015 - FAVARO, DEBORAH; ROCHA, FLAVIO; DAMATTO, SANDRA R.; WAKASUGI, DENISE; SILVA, PAULO S.
Rare earth element distribution in a sediment profile from Jurumirim Reservoir, São Paulo State, Brazil, by NAA and ICP-MS
2015 - FAVARO, DEBORAH; ROCHA, FLAVIO; DAMATTO, SANDRA R.; WAKASUGI, DENISE
Trace metal and rare earth elements in a sediment profile from the Rio Grande Reservoir, São Paulo, Brazil: determination of anthropogenic contamination, dating, and sedimentation rates
2016 - FRANKLIN, ROBSON L.; FAVARO, DEBORAH I.T.; DAMATTO, SANDRA R.
Sedimentation rates by sup(210) Pb method and trace elements by INAA in two sediment cores from the Tiete river, São Paulo, Brazil
2014 - DAMATTO, SANDRA R.; ROCHA, FLAVIO R.; BAUMGARDT, DAIANE; CASTRO, LUCAS M.; TAPPIZ, BRUNO; SILVA, PAULO S.C. da; FAVARO, DEBORAH I.T.
Total Mercury in sediment samples from Rio Grande Reservoir, SP, Brazil, by FIA-CV-AAS technique in sediment cores dated by Pb-210
2004 - FAVARO, D.I.T.; MOREIRA, S.R.D.; MOREIRA, E.G.; MAZZILLI, B.P.; CAMPAGNOLI, F.
Major and trace elements in sediments from Viração Logoon, Fernando de Noronha Archipelago, Brazil
2004 - FAVARO, D.I.T.; OLIVEIRA, S.M.B.; DAMATTO, S.R.; MENOR, E.A.; MORAES, A.S.; MAZZILLI, B.P.
Fernando de Noronha is an isolated group of 21 volcanic islands and located in the South Equatorial Atlantic, approximately 545 km from Recife, PE, Brazil. This archipelago is a protected and isolated habitat with restrict access. Viração Lagoon, a small lake located at Fernando de Noronha Island, 20 meters above the sea level, is a pristine lake located in the main island. The local drainage is restricted and ephemeral, and no connection with the general insular drainage is observed. Two sediment cores (27 and 41 cm-Iong) were extracted in this lagoon in 2000, in order to determine the chemical and mineralogical composition of the sediments. The sediments are made up of smectite, and Fe and Ti oxides. Trace elements As, Ba , Br, Co, Cr, Cs, Rb, Sb , Sc, To , Th , U, Zn and rare earths (Ce, Eu , La , Lu, Nd, Sm, Tb and Vb) were determined by instrumental neutron activation analysis (lNAA). All samples, previously dried at 60oC, were passed through a 0.065 mm sieve. The cores were sliced at every two centimeters. For the multi elemental analyses approximately 200 mg of sediment (duplicate samples) and about 150 mg of reference material and synthetic standards were accurately weighted and sealed in pre-cleaned double polyethylene bags, for irradiation ., Single and multielement synthetic standards were prepared by pipetting convenient aliquots of standard solutions (SPEX CERTIPREP) onto small sheets of Whatman no 41 filter paper. Sediment samples, reference material and synthetic standards were irradiated for 16 hours, under a thermal neutron flux of 1012 n cm-1 s- l in the IEA-R 1 nuclear reactor at Instituto de Pesquisas Energeticas e Nucleares fi IPEN. Two series of counting were made: the first after one-week decay and the second, after 15-20 days. The counting time was 2 hours for each sample and reference material, and 30 min for each synthetic standard. Gamma spectrometry was performed using a Canberra gamma X hyperpure Ge detector and associated electronics, with' a resolution of 0.88 keV and 1.90 keV for 57Co and 60Co, respectively. The validation of this methodology was performed by means of Buffalo River Sediment SRM 2704 (NISD , Soil-7 (lAEA) and BEN (Basalt-IWG-GID reference material analysis. The major elements were determined by XRF technique at IG/USP and the validation was carried out by means of JB-1 a and JG-1 a (Geological Survey of Japan) reference materials analysis. Their concentrations are similar to those reported for NASC (North American Shale Composite), except for Ba, REE , Cr, Zr and Zn , with higher concentrations. Enrichment factors for major and trace elements were calculated , using the composition of the surrounding rock (source of the sediments) as a normalizer. Results show that Cr, U, Th, Rb, and Zn are enriched and Hf, Co, Eu and Tb are depleted relative to the rock.