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In this study, a new method for the preconcentration of cadmium ions using modified aquatic macrophytes - Salvinia molesta as biosorbent in an on-line preconcentration system coupled to flame atomic absorption spectrometry (FAAS) was developed. The method is based on preconcentration of 20.0 mL sample at pH 3.75 through 35.0 mg of biosorbent at 10.0 mL min and subsequent elution with 0.5 mol L HNO. A preconcentration factor of 31-fold, linear dynamic range from 5.0 to 70.0 µg L (r = 0.9996) and detection and quantification limits of 0.15 and 0.51 µg L were obtained. The characterization of the biosorbent chemically modified with NaOH and citric acid, was performed through FTIR and SEM measurements. The method precision was found to be 3.97 % and 1.48 % for 5.0 and 60.0 µg L Cd(II) solutions, respectively. The applicability of method was checked by analysis of different kind of water samples and certified reference material.

Sowing date and fungicide application in the agronomic performance of oleaginous brassica for the biodiesel production 1 This work aims to evaluate the agronomic performance of crambe and juncea canola, sowed in the summer and winter season intervals with and without fungicide application. The cultivars used were FMS Brilhante and Terola 25A85 for crambe and juncea canola, respectively. The experimental design was randomized blocks in split plots, in which the plots were sowing dates 15 th May (E1), 1 st June (E2) and 15 th June 2014 (E3), and the split plots with and without aboveground part with fungicide (trifloxystrobin 150 g L-1 + prothioconazole 175 g L-1). The evaluated variables were plant height, thousand seed weight, seed yield, oil content and oil yield. The sowing dates had had influence only on plant height for crambe, while juncea canola had a significant effect on plant height, seed yield and oil yield. The fungicide application gave higher seed yield for crambe and for juncea canola, higher thousand seed weight, seed yield and oil yield. With the production technologies adopted for the growth of these two brassicas, it is necessary to obtain higher yields of seeds and oil, to enable the commercial exploration in the interval between the summer and winter off-season in the Northern region of Paraná state, Brazil

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