LUCIO LEONARDO
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Artigo IPEN-doc 27892 Natural radionuclides in soil profiles and sediment cores from Jundiaí reservoir, state of São Paulo2021 - GONÇALVES, P.N.; DAMATTO, S.R.; LEONARDO, L.; SOUZA, J.M.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. 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 concentrations 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. The mean activity concentrations of the radionuclides in the soil profiles 1 and 2 were, respectively: 238U – 37(1) and 32(1) Bq.kg-1; 232Th – 91(1) and 60(1) Bq.kg-1; 226Ra – 66(1) and 51(1) Bq.kg-1; 210Pb – 35(1) and 37(1) Bq.kg-1; 228Ra – 34(1) and 27(1) Bq.kg-1; 228Th – 78(1) and 58(1) Bq.kg-1; 40K – 96(2) and 171(7) Bq.kg-1. For the three sediment cores analyzed, the average activities concentrations of the radionuclides were, respectively: 238U – 64(0.5), 47(0.1) and 44(0.2) Bq.kg-1; 232Th – 122(2), 100(1) and 64(1) Bq.kg-1; 226Ra – 74(2), 71(1) and 45(1) Bq.kg-1; 210Pb – 70(3), 56(2) and 55(2) Bq.kg-1; 228Ra – 53(1), 41(1) and 33(1) Bq.kg-1; 228Th – 100(2), 92(1) and 63(2); 40K – 316(5), 237(1) and 136(2) Bq.kg-1.Artigo IPEN-doc 26177 Natural radionuclides in soil profiles and sediment cores from Jundiai reservoir, state of São Paulo2019 - GONÇALVES, PEDRO do N.; DAMATTO, SANDRA R.; LEONARDO, LUCIO; SOUZA, JOSEILTON M. deThe 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.Resumo IPEN-doc 25936 Radionuclides of natural origin in environmental samples collected in the catchment area of Ponte Nova reservoir, São Paulo, Brazil2018 - 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.Resumo IPEN-doc 22687 Assessment of natural radionuclides of the 238U and 232Th series determined in soil profiles and sediment cores from Taiaçupeba reservoir, São Paulo, Brazil2016 - SOUZA, JOSEILTON M.; DAMATTO, SANDRA R.; LEONARDO, LUCIO; SURKOV, ANDREY M.; SILVA, ANDRE R.; MADUAR, MARCELO F.; GONÇALVES, PEDRO N.Resumo IPEN-doc 21551 Radionuclides from U-238 and Th-232 series and K-40 determined in environmental samples collected in the catchment area of Ponte Nova reservoir, São Paulo, Brazil2015 - SILVA, ANDRE da; DAMATTO, SANDRA; LEONARDO, LUCIO; SOUZA, JOSEILTON; GONCALVES, PEDRO; MADUAR, MARCELO; MAZZILLI, BARBARA