The theory of acoustic sensors application in air quality control

This publication describes theoretical results, including analytical formulae for the resonance frequency shift and the dissipation of QCM-D, for two viscoelastic layers deposited onto resonator surface, as well as calculations for higher harmonics. In particular, the corrections in ∆f and ∆D due to the softness of the top layer, considered as a bulk, are written explicitly in terms of the layer's material parameters. The results can be useful for quantitative analysis of measured characteristics of QCM in AQC, environmental monitoring and biosensor applications.