METHOD FOR MONITORING THE STATUS OF AN ION MOBILITY SPECTROMETER WITH AN ION SURFACE-IONISATION THERMOEMITTER

摘要

The aim of the invention is to simplify a method for monitoring the status of an ion mobility spectrometer provided with a ion surface-ionisation thermoemitter including the spectrometer monitoring which is devoid of standard substances and carried out in a single spectrometer parameter measuring cycle. For this purpose, the inventive method consists in setting a volume airflow rate pumped through the spectrometer within a range between 2 to 10 l/min, in applying a direct voltage Uacc between the thermoemitter and the ion lens electrode in such a way that the positive connection is connected to the thermoemitter and the negative connection is connected to said ion lens electrode, in measuring the thermoemitter ion current Iem; in setting the working temperature of the thermoemitter Tp within a range of 250 to 650 °C and the Uacc value within a range between 30 and 600 Volts in such a way that the thermoemitter ion current Iem ranges from 10 11 to 10-8 Amperes; in recording an ion-drift range; in determining, for the ion current peak within the ion-drift range, the peak half-width at the half-height thereof ΔU, the maximum voltage of the peak ion current Imax and a compensating voltage value in the maximum peak of an ion current Ucm, in computing a value Kte = (Imax/ Iem) and in evaluating the status of the ion mobility spectrometer provided with the ion surface-ionisation thermoemitter according to the values ΔU, Kte, Ucm and the shape of the ion current peak of a collector, taking into account the voltage value of the thermoemitter current.