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| Martins,Cláudia R.; Alves,Janete J.F.; Carvalho,Wanessa B.D.; Cardoso,Cristiane S.C.; Andrade,Jailson B. de. |
| An investigation was made of the influence of atmospheric concentrations (15 or 130 ppbv) of NO2 on the aqueous-phase oxidation rate of S(IV) in the presence and absence of Fe(III), Mn(II) and Cr(VI) metal ions under controlled experimental conditions (pH, T, concentration of reactants, etc.). The reaction rate in the presence of the NO2 flow was slower than the reaction rate using only clean air with an initial S(IV) concentration of 10-4 mol/L. NO2 appears to react with S(IV), producing a kind of inhibitor that slows down the reaction. Conversely, tenfold lower concentrations of S(IV) ([S(IV)]º = 10-5 mol/L) caused a faster reaction in the presence of NO2 than the reaction using purified air. Under these conditions, therefore, the equilibrium shifts to... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Aqueous S(IV) oxidation; Metal ions; NO2; Acid rain formation. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652008000200006 |
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| Oliveira,Aline S.; Silva,Vilma M.; Veloso,Márcia C.C.; Santos,Gislaine V.; Andrade,Jailson B. de. |
| The main objective of this work is to evaluate the occurrence of bromophenols (2bromophenol, 4bromophenol, 2,4dibromophenol, 2,6dibromophenol and 2,4,6tribromophenol), in the flesh and guts in two species of the LutjanidaeFamily: Lutjanus synagris and Ocyurus chrysurus. The bromophenols were extracted by steam distillation with pentaneether (7:3 v/v), identified by reverse phase High Performance Liquid Chromatography (HPLCUV), and quantified bythe externalstandard method. Total bromophenol concentrations were similar in the muscle of both species, rangingfrom 36 ng g¹ to 349 ng g¹. The total bromophenol concentrations in stomach (ranging from 12 ng g¹ to 586 ng g¹)were slightly higher than in muscle. The presence of bromophenol in the muscles of the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Bromophenols; Flavor; Marine fishes; Lutjanus; Ocyurus. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652009000200002 |
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