Direct Measurement of Femtomoles of Osmium and the 187 Os/ 186 Os Ratio in Seawater
1998; American Association for the Advancement of Science; Volume: 282; Issue: 5387 Linguagem: Inglês
10.1126/science.282.5387.272
ISSN1095-9203
AutoresS. Levasseur, Jean‐Louis Birck, Claude J. Allègre,
Tópico(s)Water Quality and Pollution Assessment
ResumoTwo depth profiles of the osmium concentration and the 187Os/186Os isotopic ratio in the Indian Ocean showed that the osmium concentration seems to be unaltered by chemical or biological processes occuring in seawater; accordingly, osmium is conservative. These data were obtained from an experimental method that eliminated the problems related to osmium preconcentration. This method led to a new evaluation of the concentration of osmium in seawater; the mean concentration of osmium and the 187Os/186Os ratio are equal to 10.86 +/- 0.07 picograms per kilogram and 8.80 +/- 0.07, respectively. The results suggest the existence of an organocomplex that dominates the speciation of osmium in seawater.
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