Gas sensor measurement system capable of sampling volatile organic compounds (VOCs) in wide concentration range

摘要: Abstract A gas sensor measurement system has been developed by using a vapor-generating bubbler, analyte-diluted delivery lines and detection chamber. The bubbler with perforated disk design permits to pick up analyte vapor fixed efficiency under carrier flow rate of 0.5–100 sccm. pickup was modulated logarithmically varying the temperature. practically controllable range in acetone flux nearly three orders magnitude through variation rate, an order use bubble temperature, independently. generated diluted efficiently cascading two-step process which leads homogeneous mixing ratio dilution:carrier = 500:0.25, then delivered into small-gapped planar chamber operated at room newly-designed induces fast equilibrium high local concentration on surface, thus resulting short time higher response magnitude. From measuring chemoresistive responses carbon black-polymer composites upon exposure analyte, confirmed be reliably applicable wide from 3.7 ppm 10.7%.