| Texto completo | |
| Autor(es): |
Oliveira, Evilim M.
;
Ferreira, Edilene C.
;
Neto, Jose A. Gomes
;
Donati, George L.
;
Jones, Bradley T.
Número total de Autores: 5
|
| Tipo de documento: | Artigo Científico |
| Fonte: | SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY; v. 283, p. 6-pg., 2022-08-11. |
| Resumo | |
Raman spectroscopy (RS) was used to identify and quantify different nitrogen species in fertilizers. This is a fast and inexpensive method that requires no extensive sample preparation. Urea and nitrate were determined at 1000 and 1045 cm-1, respectively. Calibration plots obtained for these analytes showed adequate linearity, with regression coefficients (r) of 0.9989 and 0.9976, respectively. Ammonium was determined by difference after total N determination by high-resolution continuum source flame molecular absorption spectrometry (HR-CS FMAS), which provided a calibration plot with r = 0.9960. The inline coupling of RS and HR-CS FMAS allowed for a fast sequential determination of ammonium, nitrate, and urea, with limits of detection of 0.03 mg/L ammonium, 0.03 mg/L nitrate, and 0.01 mg/L urea. Relative standard deviations were <= 11 %, and the external standard calibration method provided accurate results for all analytes determined in certified reference mate-rials, raw materials, and commercial samples of fertilizers. For comparison purposes, all samples were also analyzed by traditional Kjeldahl method. The RS HR-CS FMAS method was further validated by addition and recovery experiments, which provided recoveries in the 93 - 113 % range. (AU) | |
| Processo FAPESP: | 19/07537-6 - Estudos de estratégias de análise espectroquímica por hr-cs aas, libs e espectroscopia raman |
| Beneficiário: | José Anchieta Gomes Neto |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |