Patent ID: 8487240
Filing Date: 2013-07-16
Classification: G01N

Abstract:
1. A method for monitoring chemical species in a gas flow, the method comprising: a) ionizing a sample of gas; b) passing the ionized gas sample through an ion flow channel along a longitudinal axis thereof, the channel being subject to a generated DC electric field which is transverse to the longitudinal axis of the channel; c) monitoring over time the electric current at a detector electrode arranged to intercept at least some of the ions so as to generate a signal from the detector electrode, wherein the detector electrode detects ions which flow parallel to the longitudinal axis of the ion flow channel and transverse to the DC electric field, with a change in current being indicative of a change in the composition of chemical species in the gas flow; and d) providing a characteristic of the sample of gas by comparing the signal from the detector electrode with a magnitude of the generated DC electric field at the detector electrode, whereby a resulting electric current versus a voltage graph of the detector electrode is used as a characteristic of the sample of gas.