Interelement effects are often experienced between the various constituents of metal alloys, when analyzed in spark or arc discharges. Investigating the effects due to varying composition of the analytical material in the discharge column, by time-resolved spectroscopy, to better explain interelement effects, precautions must be taken to safeguard against the effects of selective evaporization, which are not interelement effects in the true sense. Introducing fresh sample into the analytical gap for each discharge offers a means to overcome the effects of selective evaporization.
P. E. Walters and T. Monaci, "A Rotating-Disk Sample Holder for the Sparking of Flat-Metal-Disk Samples," Appl. Spectrosc. 25, 678-680 (1971)