Panels a–e: frequency vs. temperature correlation plots for the five QCMs, retrieved during a commanded MBS active heatings. Panel f: QCM5 thermal cycle reported as an example of the thermal hysteresis. Red dots correspond to the frequency vs. temperature data measured for QCM5 during the MBS active heating; blue dots are the data corresponding to the subsequent QCM5 passive cooling. Comparing the different panels it is evident that QCMs do not have monotonic trends and that each QCM has a specific behavior with respect to temperature variations.