液体介质中厚度切变石英晶体传感器的特征阻尼研究

本文提出一个新概念：特征阻尼系数ｋｃ。用来区分液体中振荡的厚度切变石英晶体传感器由质量负载和液体阻尼分别引起的频率偏移。理论推导表明，当石英晶体表面附着的质量没有变化时，特征阻尼系数Ｋｃ０的大小与附着的液体或固体性质无关，只取决于晶体谐振器自身的参数，如基频、电极面积和谐波次数等。

Study on the Characteristic Damping of the Thickness Shearing Quartz Crystal Sensors in Liquids

A new concept is introduced that characteristic damping coefficient kc is used to distinguish between the effects of mass loading and liquid damping of a quartz resonator vibrating in liquids. It is derived that the value of kco has nothing to do with the properties of liquid and solid deposited on the quartz crystal. It only depends on the parameters of the crystal resonator,such as fundamental frequency,the area of the electrode and the overtone number.The effect of mass loading occurs only when kc varies. By measuring the frequency and amplitude simultaneously,the influence on kco of fundamental frequency,electrode area and overtone number of a 10MHz AT cut quartz crystal resonator is studied.The experimental results fit the theory well.