A METHOD FOR MEASURING THE CONCENTRATION OF NITROGEN IN ARGON BY MEANS OF IONIZATION MOBILITY SPECTROMETRY

摘要

A METHOD FOR CARRYING OUT NITROGEN ANALYSIS BY IONIZATION MOBILITY SPECTROSCOPY, AT CONCENTRATIONS OF FEW PARTS PER BILION (ppb) IN ARGON IS DESCRIBED. THE METHOD INVOLVES THE ADDITION OF HYDROGEN IN CONCENTRATION OF AT LEAST 5 PPB AND LOWER THAN 100 PARTS PER MILION (ppm) TO THE ARGON TO BE ANALYZED; THE HYDROGEN ADDITION STEP IS POSSIBLY PRECEDED BY A PURIFICATION OPERATION OF THE ARGON FLOW, SO AS TO REDUCE THE TOTAL CONCENTRATION OF IMPURITIES OTHER THAN NITROGEN UNDER 1 ppb.