| 摘要 |
A detection system for a mineral acid or organic acid or alkali comprises a pair of conductors separated by an insulating material such as microporous PTFE, which is impregnated with a substance which is hydrophobic but which, on contact with a said acid or alkali, reacts to form a substance capable of transmitting the acid or alkali, thereby varying an electrical characteristic substance such that a physical characteristic, e.g. impedance or capacitance, of the insulating material, and means for detecting the variation of said electrical characteristic. |
