| 摘要 |
A measuring device is provided for determining the type and/or concentration a gaseous analyte from a set of analytes in a gaseous carrier. It comprises a housing (10) having a passage (16) to a cavity (17). A gas sensor (18) with a heated metal-oxide sensing layer (21) is arranged in the cavity (17). In order to gain a better understanding of the type of the analyte, diffusion effects are exploited by taking into account that the diffusion process through the passage (16) as well as the catalytic reaction rate at the metal-oxide sensing layer depend on the type of the analyte. These material parameters can be determined by taking several measurements in a non-steady state of the concentration of the analyte within the cavity (17), by for instance changing the analyte concentration outside the cavity (17) or while varying the reaction rate by, for instance, thermal cycling or pulsing the heated metal oxide sensing layer (21). |
