Atomization process and a model governing the rate of atom evaporation from the surface of the graphite cup inserted in the inductively coupled plasma are discussed. Several models proposed in graphite furnace atomic absorption spectrometry are reviewed and modified to be applicable to emission spectrometry. The relation between the number of atoms at the cup surface N and the number of atoms released by the surface in unit time
n (t) is deduced to be given by an equation
n (t) ∝
N exp (-
E/RT). The effect of
rf power on time-dependent signal profiles has been also investigated and is discussed based on the equation. The atomization processes of Sn, Fe, Ni, Cr mainly proceed after the cup temperature reached the maximum, so that the temperature is regarded to be constant in the equation, resulting that the relation between
n (t) and
t is simple. Experimental results for those elements are well explained by the equation.
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