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	Provedor de dados Rev. Bras. Ciênc. Solo (3) Autor Gilkes,Robert (3) Melo,Vander Freitas (2) Batista,Araína Hulmann (1) Batista,Araína Hulmnn (1) Costa,Liovando Marciano da (1) Fontes,Maurício Paulo Ferreira (1) Oliveira,Teogenes Senna de (1) Roberts,Malcolm (1) Souza,José João Lelis Leal de (1) Mais... Palavra-chave Aqua regia (1) Barite (1) Boiling nitric acid (1) EPA 3051A (1) EPA 3052 (1) Heavy metals (1) Isomorphic substitution (1) Microwave extraction (1) Nonexchangeable K (1) Plumbogummite (1) Polished sample (1) Principal component analysis (1) Rainforest soils (1) XRF (1) Mais... Tipo do documento Info:eu-repo/semantics/article (3) Ano 2018 (2) 2016 (1) País Brazil (3) Idioma Inglês (3)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 3 Primeira ... 1 ... Última Microwave Acid Extraction to Analyze K and Mg Reserves in the Clay Fraction of Soils Rev. Bras. Ciênc. Solo Batista,Araína Hulmann; Melo,Vander Freitas; Gilkes,Robert. ABSTRACT: Extraction of K and Mg with boiling 1 mol L-1 HNO3 in an open system for predicting K and Mg uptake by plants is a method of low reproducibility. The aim of this study was to compare the extraction capacity of different acid methods relative to hydrofluoric acid extraction for K and Mg. A further objective was to develop a chemical extraction method using a closed system (microwave) for nonexchangeable and structural forms of these nutrients in order to replace the traditional method of extraction with boiling HNO3 on a hot plate (open system). The EPA 3051A method can be used to estimate the total content of K in the clay fraction of soils developed from carbonate and phyllite/mica schist rocks. In the clay fraction of soils developed from... Tipo: Info:eu-repo/semantics/article Palavras-chave: EPA 3051A; EPA 3052; Aqua regia; Boiling nitric acid; Microwave extraction; Nonexchangeable K. Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832016000100431 Identification of Heavy Metals in Crystals of Sand and Silt Fractions of Soils by Scanning Electron Microscopy (SEM EDS/WD-EPMA) Rev. Bras. Ciênc. Solo Batista,Araína Hulmnn; Melo,Vander Freitas; Gilkes,Robert; Roberts,Malcolm. ABSTRACT Studies of heavy metals are concentrate on clay fractions, but coarser fractions of the soil can constitute significant sources of structural forms of heavy metals. The aim of this study was to evaluate the occurrence of heavy metals in the structure of minerals of the sand and silt fractions of soils from three different parent materials (metamorphic rocks and granite) in southern Brazil using SEM/EDS - Scanning Electron Microscopy with Energy Dispersive Spectroscopy and with WD-EPMA - with Wavelength Dispersive-Electron Probe Microanalysis. We sampled soils from two areas naturally rich in heavy metals, with high mineral deposits (galena - PbS) hosted in carbonate rocks and phyllite/mica schist. The main form of Ba in the sand and silt fractions... Tipo: Info:eu-repo/semantics/article Palavras-chave: Plumbogummite; Barite; Isomorphic substitution; Polished sample. Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832018000100408 Geochemical Signature of Amazon Tropical Rainforest Soils Rev. Bras. Ciênc. Solo Souza,José João Lelis Leal de; Fontes,Maurício Paulo Ferreira; Gilkes,Robert; Costa,Liovando Marciano da; Oliveira,Teogenes Senna de. ABSTRACT: Evaluating soil geochemical diversity in the Amazon Basin has been a challenge largely because most study sites have been at the edge of the basin and it is difficult to get samples in such a region. Here we show that even among the most weathered soils, physicochemical soil properties express lithology. Our results are based on topsoil samples collected from different locations in minimally disturbed areas in the state of Amazonas, Brazil. Soil properties were measured using methods which are suitable for highly developed soils. The Chemical Index Alteration and Weathering Index of Parker was calculated based on the content of metal(loid)s in soils determined by X-ray fluorescence. Descriptive statistics, Pearson correlation, and Principal... Tipo: Info:eu-repo/semantics/article Palavras-chave: Heavy metals; Principal component analysis; XRF; Rainforest soils. Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832018000100403 Registros recuperados: 3 Primeira ... 1 ... Última

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