SIZE AND DISTRIBUTION OF PARTICLES DEPOSITED ELECTROSTATICALLY ONTO THE PLATFORM OF A GRAPHITE-FURNACE OBTAINED USING LASER-ABLATION SAMPLING

Electrostatic particle deposition onto the platform of an ETA graphite furnace was investigated by solid sampling employing laser ablation. The aerosol generated by laser ablation is transported into the furnac e-by an Ar gas flow. It is piped into the tube through the dosing hole via a capillary. The deposition onto the graphite platform is achieve d by impact as well as electrostatically by a discharge. The depositio n efficiency was investigated with steel samples, the sample distribut ion on the graphite platform and the size of the deposited particles w as investigated with steel, phosphate rock and plastic samples. Employ ing electrostatic precipitation, particles with diameters down to abou t 5 nm are deposited. The efficiency is measured by an additional exte rnal precipitator, showing almost quantitative deposition of the intro duced particles. (C) 1997 Elsevier Science B.V.