摘要 |
<p>A method and sensor for monitoring chemical species in a gas flow are described. An ionised sample of gas is passed through a flow channel, with a DC electric field applied transverse to the longitudinal axis of the channel. Any electric current produced by the ion flow is measured, with variations in the current being indicative of a change in composition of the gas flow. In certain embodiments, the DC field may be varied over time, to sweep the field voltage. The detected current against field voltage graph may be taken as a profile of a particular gas composition. Variations in the profile again are indicative of a change in gas composition.</p> |