GRAPHITE-FURNACE ATOMIC-ABSORPTION SPECTROMETRY WITH CONTINUOUS LASERSAMPLING BY COMPLETE VAPORIZATION OF SOLID SAMPLES AND ITS APPLICATION TO THE DETERMINATION OF COPPER AND LEAD IN GEOLOGICAL SAMPLES

A system of continuous laser vaporization coupled with graphite-furnac e atomic absorption spectrometry and its characteristics for the direc t analysis of solid samples are described. A detailed investigation in dicated that the system was free from the influence of sample inhomoge neity when the solid samples were pulverized to under a size of 200 me sh. In addition, the continuous laser mode showed less matrix interfer ence on the atomic absorption signals than did the pulsed-laser mode. The procedures for sample preparation and direct analysis of a solid s ample are presented. The system was applied to the determination of tr ace copper and lead in geological solid samples; the obtained results show good agreement with the certified values.