Data/hora: 05/06/2024 12:59:14

Biblioteca(s): | Embrapa Pecuária Sudeste.
Data corrente: | 26/01/2004
Data da última atualização: | 29/06/2023
Autoria: | ROSA, C. R.; FRESCHI, G. G.; MORAES, M. de; GOMES NETO, J. A.; NÓBREGA, J. A.; NOGUEIRA, A. R. de A.; SACRAMENTO, L. V.
Afiliação: | CASSIA REGINA ROSA, Universidade Estadual Paulista; GIANPAULO GIOVANNI FRESCHI, Universidade Estadual Paulista; MERCEDES DE MORAES, Universidade Estadual Paulista; JOSÉ ANCHIETA GOMES NETO, Universidade Estadual Paulista; JOAQUIM ARAÚJO NÓBREGA, Universidade Federal de São Carlos; ANA RITA DE ARAUJO NOGUEIRA, CPPSE; LUÍS VITOR SACRAMENTO, Universidade Estadual Paulista.
Título: | Tungsten permanent chemical modifier for fast estimationsof contents in soil by graphite furnace atomic absorption spectrometry.
Ano de publicação: | 2003
Fonte/Imprenta: | Journal of agricultural and Food Chemistry, v. 51, p. 3920-3923, 2003.
DOI: | https://doi.org/10.1021/jf0212439
Idioma: | Inglês
Conteúdo: | A tungsten carbide coating on the integrated platform of a transversely heated graphite atomizer was used as a modifier for the direct determination of Se in soil extracts by graphite furnace atomic absorption spectrometry. Diethylenetriaminepentaacetic acid (0.0050 mol L-1) plus ammonium hydrogencarbonate (1.0 mol L-1) extracted predominantly available inorganic selenate from soil. The formation of a large amount of carbonaceous residue inside the atomizer was avoided with a first pyrolysis step at 600 °C assisted by air during 30 s. For 20 ?L of soil extracts delivered to the atomizer and calibration by matrix matching, an analytical curve (10.0?100 ?g of L-1) with good linear correlation (r = 0.999) between integrated absorbance and analyte concentration was established. The characteristic mass was 63 pg of Se, and the lifetime of the tube was 750 firings. The limit of detection was 1.6 ?g L-1, and the relative standard deviations (n = 12) were typically <4% for a soil extract containing 50 ?g of L-1. The accuracy of the determination of Se was checked for soil samples by means of addition/recovery tests. Recovery data of Se added to four enriched soil samples varied from 80 to 90% and indicated an accurate method.
Palavras-Chave: | Diethylenetriaminepentaaacetic; GFAAS; Tungsten permanent modifier.
Thesaurus Nal: | selenium; soil.
Categoria do assunto: | W Química e Física
Registro original: | Embrapa Pecuária Sudeste (CPPSE)
Exemplares: | CPPSE - (14985-1) - UPC - AP - DD - PROCI-2003.00011 - ROS - 2003.00011 - DIS