EXTENSIONS OF THE QUARTZ-CRYSTAL-MICROBALANCE TECHNIQUE

The high mass sensitivity of the quartz-crystal microbalance is explai ned by the very high acceleration of the particles on the surface of t he quartz resonators. The sensing properties of quartz resonators in c ontact with a solid, liquid or gas medium are explained within the ene rgy transfer model. The use of the quartz-crystal microbalance is exte nded up to the Curie point (573 degrees C) by employing a dual resonat or. Standing compressional waves, generated by a shear-mode quartz res onator in a liquid or by a compressional-mode quartz resonator in a ga s, are used for sensing small changes in the composition of a liquid o r gas, respectively.