Section of a sample zone, split in the holding coil is diverted into reactor (A), where it is treated by using different:
or other means, that will yield a desired information on sample composition.
Thus, for simultaneous assay of nitrite and nitrate (B), sample zone is split and reacted with Gries reagent in holding coil, yielding the first peak for nitrite (C), while nitrate in the sample portion sent into Cd column is reduced to nitrite, yielding, after reaction with Gries reagent, the second peak which is the sum of nitrate and nitrite. Blue trace mixture of 100 ppB of nitrate with 100ppB nitrite, green trace 100ppB nitrite only. (2.2.22.)