The method comprises the following steps of: (1) carrying out ultrasonic washing and drying treatment to an adsorbing material carrier until a constant-weight carrier is formed;
本发明的方法包括以下步骤：（1）对吸附材料载体进行 超声洗涤和干燥处理，直到处理成恒重载体；
2
The ultrasonic sensor produces a data carrier utilizing very high frequencies that are outside the human's audible range.