| 摘要 |
A method for detecting a chemical species includes providing in a vessel (12) an acidic sample (5) containing an ionic chemical species to be measured and a headspace above the acidic sample, adding a preselected reducing agent to the aqueous sample and forming an ionizable chemical gas species in the aqueous sample where the ionizable chemical species to be measured evolves out of the aqueous sample and into the headspace forming a gas sample (selective hydride generation), moving the gas sample containing the ionizable chemical gas species from the headspace of the vessel out (16) of the vessel and through a precolumn (22) to remove water vapour, then moving the gas sample containing the ionizable chemical gas species into one of (1) a detector system (10) comprising either a gas chromatograph - photoionization detector (GC/PID) or a photoionization detector (PID) or (2) an oxygen-retaining column (20), followed by said the detector system (10) comprising either a GC/PID or PID. |
