| 摘要 |
PURPOSE:To measure only the concn. of a nitrogen oxide at a low cost by applying a voltage equal to or below 0.5 V between both the electrodes of an oxygen pump. CONSTITUTION:When a voltage equal to or below 0.5 V is applied between both the electrodes 4B and 4C of an oxygen pump 4, simple substance oxygen in a gas to be measured in a space S1 is pumped by a pump 4 out of a cell 1. At the same time, nitrogen oxide is electrolyzed into oxygen and nitrogen on the electrodes in the cell 1 and the electrolyzed oxygen is pumped out of the cell 1 like the simple substance oxygen. Since the voltage between the electrodes 4B and 4C is restricted to 0.5 V or below, the other oxides are not electrolyzed and only oxygen in the nitrogen oxide is pumped out by the pump 4. Thus, a current corresponding to the quantity of discharge oxygen flows between the electrodes 4B and 4C and, by measuring the current by an ammeter 6, the total quantity of the simple substance oxygen in the gas to be measured and oxygen in the nitrogen oxide can be measured. |
