par Hoenig, Michel 
;Wollast, Roland
Référence Spectrochimica acta, Part B: Atomic spectroscopy, 37, 5, page (399-415)
Publication Publié, 1982
;Wollast, Roland Référence Spectrochimica acta, Part B: Atomic spectroscopy, 37, 5, page (399-415)
Publication Publié, 1982
Article révisé par les pairs
| Résumé : | This work shows the analytical possibilities of an electrothermal atomizer for the direct determination of trace metals in sea-water. The high background signals generated by the matrix perturb in particular volatile elements because of the low decomposition temperature allowed. In the case of cadmium, addition of ascorbic acid to the sample permits the modification of the atomization mechanism and the reduction of the optimum temperature. Under these conditions, absorption peak of the cadmium precedes the background absorption and consequently the analysis is no longer limited by the magnitude of the matrix signal: the determination of cadmium concentrations far below the μg-1 level is easily possible. Although the direct determination of the other elements should be in principle less disturbed by the background, the analytical performance is poorer than for cadmium. Limits of determination of the order from 0.1 to 1 μg-1 can be reached for chromium, copper and manganese. Lead and nickel appeared to be the most difficult elements; their direct determination is only possible in polluted coastal or estuarine waters. The injection of the sample as an aerosol into hot graphite tube showed to be well adapted to this kind of investigations. The simultaneous visualization of specific and background signals allows interpretations which until now were impossible with commercially available apparatus. © 1982. |
