SEEN TO DETERMINE THE DIFFERENCE BETWEEN A CHEMICAL BASE AND A BASED-DOWN FORM

摘要

A process for determining the interactions between a solution and a body immersed in the solution, comprising the steps of measuring the sound emission from the body, such as sound waves in the ultrasonic range, while the solution and body are interacting and using this measurement to determine the interaction. The process can be used, inter alia, during the chemical removal of material from a body by a solution, such as chemical etching, to determine the degree of exhaustion of the solution. Moreover, the sound emission can be used in the control of further interaction between the solution and body.