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Dias,Nivea Maria Piccolomini; Caires,Eduardo Fávero; Pires,Luiz Fernando; Bacchi,Márcio Arruda; Fernandes,Elisabete Aparecida de Nadai. |
The objective of this work was to determine the impact of phosphogypsum application on 226Ra and 228Ra activities in the soil and on their accumulation in soybean grains. A field experiment was carried out in Paraná state, Brazil, on a loamy Typic Hapludox, under no-till system, with increasing phosphogypsum rates: 4, 8, and 12 Mg ha-1. GammA ray spectrometry was carried out using HPGe detectors with 45 and 10% relative efficiencies, for soybean grains and soil, respectively. No increment of 226Ra and 228Ra activities was observed due to the increase in phosphogypsum rates in the soil, and a small reduction was noticed in the grains. Average values found for 226Ra and 228Ra activities were 37 and 57 Bq kg-1 in the soil and 1.44 and 3.19 Bq kg-1 in soybean... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Glycine max; Gamma spectrometry; Radioactivity; 226Ra; 228Ra. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2010001200017 |
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CARDINALI,V.C.B.; DIAS,A.C.R.; MUELLER,T.C.; ABERCROMBIE,L.; STEWART JR.,C.N.; TORNISIELO,V.L.; CHRISTOFFOLETI,P.J.. |
In Brazil, few research works on mechanisms of weed resistance to glyphosate have been conducted so far. Therefore, this research aimed to study analytical procedures determining the relation between the concentration of plant shikimate after glyphosate application and the plant resistance to this herbicide; and evaluate the glyphosate absorption and translocation into two resistant ® and susceptible (S) horseweed biotypes to glyphosate. Horseweed plants with nine true leaves received glyphosate (720 g a.e. ha-1), and 2, 3, 4, 7 and 10 days after application (DAA) the concentration of shikimic acid was measured by HPLC. In another experiment, plants were treated with radiolabeled glyphosate (14C) (1.456 MBq mmol-1 specific activity) and radioactivity was... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Conyza bonariensis; High Performance Liquid Chromatography; EPSPS; Selection; Radioactivity. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582015000100109 |
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Martins,Maristela; Pacheco,Ariane Mendonça; Lucas,Ana Cyra Santos; Andrello,Avacir Casanova; Appoloni,Carlos Roberto; Xavier,Jose Junior Mendonça. |
A study was carried out to evaluate the association of levels of radioactivity, selenium and aflatoxin in shelled Brazil nuts, which were classified in different sizes, for export. The selenium determinations were performed by inductively coupled plasma optical emission spectrometry (LOQ = 3.0 µg g-1), and aflatoxins were detected by Liquid chromatography-mass spectrometry (LOQ = 0.85 µg kg-1), recovery rates were between 92 and 100%. Radioactivity was measured by high-resolution gamma spectrometry. The selenium mean concentration was (22.7 ± 7.4) µg g-1. (n = 30). Mean activities determined for the following radium isotopes were: 15.77 Bq kg-1 for 224Ra, 104.8 Bq kg-1 for 226Ra and 99.48 Bq kg-1 for 228Ra. For 226Ra, the levels did not vary significantly... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Radioactivity; Selenium; Bertholletia excelsa. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672012000100018 |
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