| 摘要 |
A method of operating an apparatus comprising a submersible PID for the detection of volatile compounds in water 30, which detector includes a sensing chamber 20, gas permeable membrane 18 for allowing gas dissolved in the water into the sensing chamber, a source of ionising radiation 12 for irradiating the chamber and electrodes 24, 26 within the chamber for passing a current in response to ionisation of any gas therein by the ionising radiation; which method comprises activating the source intermittently and analysing the rate of change of resulting ionisation current in a transient period between each instant of reactivation of the source and a steady state current, to indicate solubility in water of any volatile compound in the chamber. A further method includes agitating the water contacting the membrane and correlating an ionisation current with a degree of agitation. |
