摘要 |
A method for identifying an unknown gas using a diffusion limited sensor providing an electrical signal output when exposed to the gas. According to the method, a sensor is disposed in a chamber of fixed volume and having a gas input and gas output through which the gas flows, and the chamber is connected to a source of a known test gas of known concentration and known diffusion coefficient Dk. The input to the chamber is opened, causing the sensor to be exposed to the known test gas until a steady state electrical signal output from the sensor is obtained. The time Tk necessary for the sensor to attain a predetermined percentage of the steady state output is determined. The chamber is then connected to a source of unknown gas, and the input is opened, and time Tu necessary for the sensor to attain the predetermined percentage of a steady state output for the unknown gas is determined. The diffusion coefficient Du for the unknown gas is calculated by the formula Du=Dkx(Tk/Tu); and the unknown gas is identified by its calculated diffusion coefficient.
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