Analogy of the fluids on both the active (deposition area) and non-active electrodes part of the high-pressure high-temperature QCM-D (QHPT) vessel. If air occupies both sides of the sensor (A), the energy loss (Dissipation energy) by the sensor is negligible (~0). On the other hand, if the system fluid occupies the non-active part of the sensor whiles the test fluid also occupies the active electrode part of the sensor (B). Hence, the total energy lost by the sensor is due to the presence of the fluids above and beneath the sensor in addition to the attenuation due to the adsorbed film.