SANDRA REGINA DAMATTO

SANDRA REGINA DAMATTO

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One year of Be-7 measurement in rainfall collected in different points in the city of São Paulo, Brazil
2024 - DOMINGOS, R.M.; LEONARDO, L.; DAMATTO, S.R.; MIRANDA JUNIOR, P.; ISIKI, V.L.; NISTI, M.B.; ALENCAR, M.M.; TEIXEIRA, L.F.L.; MADUAR, M.F.; NETO, J.O.A.
Caracterização química inorgânica e radiológica de oleaginosas consumidas na cidade de São Paulo
2024 - NASCIMENTO, B.F.; DAMATTO, S.R.; LEONARDO, L.; SILVA, T.C.
Inorganic chemical characterization of the soil from the springs at RPPN Fazenda Renópolis
2024 - RODRIGUES, C.E.C.; DAMATTO, S.R.; LEONARDO, L.
Natural radionuclides in surface soils from Biritiba-Mirim reservoir, state of São Paulo, Brazil
2024 - GONCALVES, P.N.; DAMATTO, S.R.; LEONARDO, L.; COTRIM, M.E.B.; SILVA, T.C.
Pb-210 activity concentration measured in rainfall in different sampling heights
2024 - ALMEIDA NETO, J.O.; DAMATTO, S.R.; MADUAR, M.F.; LEONARDO, L.; TEIXEIRA, L.F.L.
Challenges in measuring 22Na in rainfall by gamma spectrometry in the city of São Paulo, Brazil
2023 - DAMATTO, S.R.; DOMINGOS, R.M.; TEIXEIRA, L.; ISIKI, V.L.; ALENCAR, M.M.; LEONARDO, L.
Na-22 is a naturally occurring radionuclide of cosmogenic origin with half live of 2.6 years, being a beta and gamma emitter (541keV and 1274.5keV, respectively). This cosmogenic radionuclide is mainly formed when cosmic rays interact with argon nucleus, occurring a fragmentation of this nucleus. The process of production of 22Na occur continually in upper atmosphere, lower stratosphere and rainfall is the predominantly process of deposition of cosmogenic radionuclides in terrestrial surface. Na-22 together with 7Be (T1/2) = 53.3 d, gamma ray 476.7keV) can be used as tracers in studies of aerosol transport between layers of the atmosphere. At the same time 22Na is rarely used in these studies due to its extremely low abundance in rainfall. The objectives of this work were to present the first results 22Na activity concentration measured in rainfall collected at the IPEN campus located in São Paulo, Brazil. Large volumes of rainfall samples were collected from October 2022 to April 2023, totaling 20 samples, and 22Na activity concentration was measured by non-destructive gamma-ray spectrometry using a coaxial Be-layer HPGe detector with 46% relative efficiency and associated electronic devices and live counting time varying from 250,000 s to 500,000 s; the rainfall volumes ranged from 14 L to 164 L. The collection container was previously acidified with 1mol L-1 HNO3 to avoid loss of radionuclide by absorption on the container walls. The first eight rainfall samples were collected in a catchment area of 1m2, which was not enough to measure the radionuclide, since all the determined results were smaller than the detection limit of the methodology. After these results, it was decided to increase the catchment area by collecting rainfall samples from the roof of the laboratory building, in an area of 78 m2; the container used to collect samples from this area was also acidified with 1 mol L-1 HNO3. In this new area, 12 rainfall samples were collected, however, as the volume of rainfall was very large in the rains collected, only one sample was acidified, a rainfall of 2 mm and a volume of 98 L; in the other samples, the large volume of rain did not allow the water to become acidic because the collection container overflowed with water. In the acidified rainfall sample, the result of 0.725 ± 0.252 Bq L-1 was determined for the radionuclide 22Na. With this result, it is possible to prove the importance of both the catchment area and the acidulation of the sample in the determination of trace radionuclides in rainfall samples.
Study of 7Be activity concentration in rainfall as a function of sampling height
2022 - ALMEIDA NETO, J.O.; DAMATTO, S.R.; MADUAR, M.F.; LEONARDO, L.; TEIXEIRA, L.F.; DOMINGOS, R.M.
Natural radioactivity in oilseeds commercialized in the city of São Paulo, Brazil
2022 - LEONARDO, L.; DAMATTO, S.R.; MADUAR, M.F.
Natural radionuclides in soil profiles and sediment cores from Jundiai reservoir, state of São Paulo
2019 - GONÇALVES, PEDRO do N.; DAMATTO, SANDRA R.; LEONARDO, LUCIO; SOUZA, JOSEILTON M. de
The activity concentration of natural radionuclides in soils and sediments is dependent on many factors, such as the rock parental material, pedogenic and weathering processes, physical and chemical properties of the environment, anthropogenic sources, among other aspects. Naturally occurring radiation in the environment is mostly due to the decay of 238U and 232Th series; another important source of natural radiation is the radionuclide 40K. Reservoirs are artificial systems made in order to stock riverine and rainwater to supply water to the population. There are few studies about the levels of natural radionuclides in reservoirs in both, international and national, literature. The objective of this paper was to evaluate the activity concentration of 238U and 232Th by Instrumental Neutron Activation Analysis and 226Ra, 210Pb, 228Ra, 228Th and 40K by gamma spectrometry in two soil profiles and three sediment cores collected in the catchment area of Jundiai reservoir, located in the state of São Paulo, Brazil. Principal component analysis was applied to verify the correlation of the activity concentrations of the natural radionuclides with physical and chemical properties of soil and sediment samples. In the soil profiles, the radionuclides that showed higher activity concentration when compared to the UNSCEAR values were 232Th in the both profiles and 238U only in one; for the sediment cores, the activity concentrations of 238U and 232Th were higher than the UNSCEAR values in all the samples analyzed and also for the radionuclide 226Ra in two sediment cores.
Radionuclides of natural origin in environmental samples collected in the catchment area of Ponte Nova reservoir, São Paulo, Brazil
2018 - SILVA, A.R.; DAMATTO, S.R.; LEONARDO, L.; GONÇALVES, P.N.; SOUZA, J.M.; MADUAR, M.F.
Natural radiation is generally classified as terrestrial primordial radiation or cosmogenic radiation. Primordial radiation is mostly due to the decay series of 238U and 232Th and is present in soil, sediments and water; another important source of natural radiation is 40K. Reservoirs are a very dynamic system with several phenomena to study, due to their huge impact on ecosystems and river flow. Ponte Nova reservoir (23°34'43.23"S, 45°56'56.76"W) is the first reservoir in a cascade system that was built in the 1970s to control the Upper Tietê River basin water flow. In the present work, the activity concentrations of 238U, 226Ra, 210Pb, 232Th, 228Th, 228Ra and 40K were determined using instrumental neutron activation analysis and gamma spectrometry in soil profiles collected in the catchment area of Ponte Nova Reservoir and sediment cores collected close to the soil samples. The highest concentration obtained in the soil samples was for 40K that varied from 49 to 2410 Bq/kg and 210Pb in the sediment samples, which varied from 20 to 774 Bq/kg. Cluster analysis and principal component analysis were applied to all the results obtained to verify a probable correlation between the radionuclides determined in the soil and sediment samples.