Electron microscope observation of thermal pre-treatment and vaporization processes of Ag-Sb and Pd-Sb systems in graphite furnace atomic absorption spectrometry

As the reproducibility of Sb in river water analysis based on graphite: fur nace atomic absorption spectrometry is not good, and the reliability is poo r when Pd is used as a matrix modifier, Ag was used instead of Pd, The reas on Ag has the function of a matrix modifier and Pd does not, was studied by observation of the atomic columns or lattice structures at the atomic leve l in binary alloys, by using a high-resolution transmission electron micros cope. Since the Ag-Sb system has the characteristic of forming an intermeta llic compound and a lower value of the activity coefficient of Sb in its in termetallic compound, Ag is able to function as a matrix modifier as a resu lt. In the case of the Pd-Sb system, the phenomenon of radical vaporization that is observed in the Ag-Sb system does not occur through changes of the phases of Pd-Sb intermetallic compounds. This fact means Pd does not have the function of a matrix modifier. (C) 1999 Elsevier Science B.V. All right s reserved.