Patent ID: 6165347
Filing Date: 2000-12-26
Classification: G01N

Abstract:
Method for identifying a reactive gas in a carrier gas, comprising the steps of:obtaining a detector which generates an electrical signal upon exposure to the gas;positioning said detector to accept gas from a manifold of defined volume with a diffusion barrier between the detector and the manifold;determining an output signal from the detector for the carrier gas without the reactive gas;directing the reactive gas and carrier gas through an inlet into the manifold, obtaining a steady state signal S from the detector indicating presence of the reactive gas and exhausting carrier gas and reactive gas from the manifold through an outlet;closing the inlet and outlet, and permitting reactive gas in the manifold to diffuse through the diffusion barrier for analysis, determining a decay profile as the steady state signal is being reduced vs. time to the output signal for the carrier gas as reactive gas is consumed;determining from the steady state signal and decay profile a diffusion coefficient for the reactive gas, and identifying the reactive gas from the diffusion coefficient.