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	Provedor de dados Rev. Bras. Ciênc. Solo (3) PAB (1) Autor Alves,Marcelo Eduardo (4) Lavorenti,Arquimedes (2) Cagliari,Joice (1) Forti,Gabriel Benjamin Siqueira (1) Mascarenhas,Yvonne Primerano (1) Miranda,Jarbas Honório de (1) Nakagawa,Fábio Keiti (1) Vaz,Carlos Manoel Pedro (1) Veronez,Maurício Roberto (1) Mais... Palavra-chave Ammonium-oxalate-extractable Al (1) Anion exchange capacity (1) Análises térmicas (1) Artificial neural networks (1) Difratometria de raios X (1) Minerais desordenados (1) Modeling (1) Multiple regression analysis (1) Método de Rietveld (1) Phosphate adsorption (1) Phosphorus buffer capacity (1) Remaining phosphorus (1) Retardation factor (1) Mais... Tipo do documento Info:eu-repo/semantics/article (4) Ano 2012 (1) 2011 (1) 2008 (1) 2004 (1) País Brazil (4) Idioma Inglês (3) Português (1)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 4 Primeira ... 1 ... Última Remaining phosphorus and sodium fluoride pH in soils with different clay contents and clay mineralogies PAB Alves,Marcelo Eduardo; Lavorenti,Arquimedes. The remaining phosphorus (Prem) has been used for estimating the phosphorus buffer capacity (PBC) of soils of some Brazilian regions. Furthermore, the remaining phosphorus can also be used for estimating P, S and Zn soil critical levels determined with PBC-sensible extractants and for defining P and S levels to be used not only in P and S adsorption studies but also for the establishment of P and S response curves. The objective of this work was to evaluate the effects of soil clay content and clay mineralogy on Prem and its relationship with pH values measured in saturated NaF solution (pH NaF). Ammonium-oxalate-extractable aluminum exerts the major impacts on both Prem and pH NaF, which, in turn, are less dependent on soil clay content. Although Prem and... Tipo: Info:eu-repo/semantics/article Palavras-chave: Ammonium-oxalate-extractable Al; Phosphate adsorption; Phosphorus buffer capacity. Ano: 2004 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2004000300006 Remaining phosphorus estimated by pedotransfer function Rev. Bras. Ciênc. Solo Cagliari,Joice; Veronez,Maurício Roberto; Alves,Marcelo Eduardo. Although the determination of remaining phosphorus (Prem) is simple, accurate values could also be estimated with a pedotransfer function (PTF) aiming at the additional use of soil analysis data and/or Prem replacement by an even simpler determination. The purpose of this paper was to develop a pedotransfer function to estimate Prem values of soils of the State of São Paulo based on properties with easier or routine laboratory determination. A pedotransfer function was developed by artificial neural networks (ANN) from a database of Prem values, pH values measured in 1 mol L-1 NaF solution (pH NaF) and soil chemical and physical properties of samples collected during soil classification activities carried out in the State of São Paulo by the Agronomic... Tipo: Info:eu-repo/semantics/article Palavras-chave: Artificial neural networks; Modeling; Multiple regression analysis. Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832011000100019 Estimating subsoil resistance to nitrate leaching from easily measurable pedological properties Rev. Bras. Ciênc. Solo Nakagawa,Fábio Keiti; Forti,Gabriel Benjamin Siqueira; Alves,Marcelo Eduardo; Lavorenti,Arquimedes; Miranda,Jarbas Honório de. Leaching of nitrate (NO3-) can increase the groundwater concentration of this anion and reduce the agronomical effectiveness of nitrogen fertilizers. The main soil property inversely related to NO3- leaching is the anion exchange capacity (AEC), whose determination is however too time-consuming for being carried out in soil testing laboratories. For this reason, this study evaluated if more easily measurable soil properties could be used to estimate the resistance of subsoils to NO3- leaching. Samples from the subsurface layer (20-40 cm) of 24 representative soils of São Paulo State were characterized for particle-size distribution and for chemical and electrochemical properties. The subsoil content of adsorbed NO3- was calculated from the difference... Tipo: Info:eu-repo/semantics/article Palavras-chave: Anion exchange capacity; Remaining phosphorus; Retardation factor. Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000500013 Comparação de procedimentos de quantificação de caulinita e gibbsita na fração argila desferrificada de Latossolos Rev. Bras. Ciênc. Solo Alves,Marcelo Eduardo; Mascarenhas,Yvonne Primerano; Vaz,Carlos Manoel Pedro. A acurada determinação dos teores dos minerais que constituem a fração argila dos Latossolos pode contribuir para o aprimoramento de seu uso e manejo. Neste trabalho, teores de caulinita e gibbsita da fração argila desferrificada de Latossolos foram determinados por calorimetria exploratória diferencial (CED) e pela aplicação do método de Rietveld a dados de difratometria de raios X (DRX), e comparados com seus respectivos teores calculados pelo método da alocação. Possivelmente, diferenças cristalográficas entre a caulinita e a gibbsita utilizadas na calibração da CED e suas respectivas contrapartidas encontradas nas amostras analisadas tenham contribuído para a menor exatidão dos teores de caulinita e de gibbsita determinados pelo referido método... Tipo: Info:eu-repo/semantics/article Palavras-chave: Análises térmicas; Difratometria de raios X; Método de Rietveld; Minerais desordenados. Ano: 2008 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832008000200012 Registros recuperados: 4 Primeira ... 1 ... Última

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