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| Lima,Erica Souto Abreu; Amaral Sobrinho,Nelson Moura Brasil do; Pérez,Daniel Vidal; Coutinho,Izabella Bezerra. |
| ABSTRACT The diversity of methods for heavy metal extraction from soils complicates comparison of results used by environmental agencies to establish quality reference values. The aim of this study was to evaluate three soil digestion methods regarding the solubilizing capacity of Ba, Cr, Cu, Fe, Mn, Ni, Pb and Zn, and to propose a standard method to establish Quality Reference Values (QRVs) for Brazilian Histosols. Twenty soil samples were selected to evaluate the USEPA 3051, USEPA 3051A and Aqua Regia methods in a closed system. The methods tested were statistically similar regarding Cu, Fe and Mn extraction from soils. However, the methods can not be considered similar for Ba, Cr, Ni, Pb and Zn; Aqua Regia recorded the highest levels, except for Ba. The... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Organic horizons; Pseudo-total content; Soil digestion methods. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832016000100428 |
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| Ribeiro,Fernando Carlos Araujo; Lauria,Dejanira da Costa; Silva,José Ivan Rodrigues; Lima,Erica Souto Abreu; Amaral Sobrinho,Nelson Moura Brasil do; Pérez,Daniel Vidal. |
| ABSTRACT A first large-scale systematic survey of natural radioactivity contents of soils of the state of Rio de Janeiro is presented, focused on the establishment of Quality Reference Values (QRVs). Undisturbed soil samples were collected from 243 areas and analyzed by gamma spectrometry. The activity contents varied largely, ranging from 12.2 to 1,029 Bq kg−1 for 40K (geometric mean of 111.1 Bq kg−1), from 3.5 to 99.8 Bq kg−1 for 226Ra (geometric mean of 29.7 Bq kg−1), and from 5.4 to 314.5 Bq kg−1 for 228Ra (geometric mean of 67.1 Bq kg−1). The highest contents of radium isotopes were found in soils developed on igneous rocks (Leptosol), and the lowest in a soil of sedimentary origin (Podzol). Among the different soil types, the radioisotope contents... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Radium; Potassium-40; Quality reference values; Soil. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832018000100500 |
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| Mattos,Amanda Guimarães de; Amaral Sobrinho,Nelson Moura Brasil do; Lima,Erica Souto Abreu; Guedes,Jair do Nascimento; Sousa,Fábio Freire de. |
| RESUMO As concentrações de metais na solução do solo são reguladas, principalmente, pelos processos de sorção. Neste estudo foi avaliada a dinâmica de sorção de Cd e Pb em 19 amostras de solos da Região do Médio Rio Paraíba - RJ, Brasil, através da comparação dos parâmetros de diferentes modelos de isotermas obtidos pelo software ISOFT após ensaios de sorção pelo método da batelada. Os resultados mostraram que a isoterma Linear é mais adequada para representar a sorção de Cd e o modelo de Freundlich para Pb e que a adsorção de Cd é fortemente influenciada pelo pH e pelas concentrações de Fe e Ca, enquanto que a adsorção de Pb é mais influenciada pelo pH, e pelas concentrações de Mn e Ca. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Metais Pesados; Modelos de sorção; Isotermas. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902016000100001 |
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| Mattos,Amanda Guimarães de; Lima,Erica Souto Abreu; Amaral Sobrinho,Nelson Moura Brasil do; Zoffoli,Hugo José de Oliveira; Pérez,Daniel Vidal. |
| ABSTRACT Quality Reference Values (QRVs) for potentially toxic elements are obtained from background levels in soils. However, this determination from mean values or percentiles is not appropriate given the variability in the natural distribution of these elements in soils. Therefore, the objective of this study was to propose a new methodology to establish the QRVs, using the Médio Paraíba region (RJ, Brazil) as an example, from groups of soils defined based on the pseudo-total levels of B, Ba, Co, Cr, Cu, Ni, Pb, and Zn through the use of multivariate analyses and discriminant functions. A total of 40 points, collected at depths of 0-20 and 20-40 cm, were used for the determination of pseudo-total contents, according to the EPA 3051A methodology. The... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Guiding values; Heavy metals; Cluster analysis. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902018000100001 |
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