| 摘要 |
PURPOSE:To enable simple and quick measurement of various gas concentrations continuously, by arranging a sensor with a plurality of electrodes at one of ion conducting plates made of a solid electrolyte. CONSTITUTION:A current-limiting type sensor C equipped with an oxygen ion conducting plate 11 made of solid electrolyte, a cap-shaped capsule 12 covered on the one side of the plate 11, a diffusion plate 13 made at the central top thereof, pairs of electrodes 14a and 14b and 15a and 15b made of a porous metal film respectively formed on both sides of the plate 11, power sources 16 and 17 for respective electrodes, an ammeter A and a voltmeter V. when a voltage Va not enough to decompose water in the atmosphere and a voltage Vb enough to decompose water are applied to the electrodes 14a and 14b and 15a and 15b respectively for measurement, the electrode 14 produces a limit current ILa corresponding to the presence of oxygen atom while the electrode 15 produces a limit current ILb corresponding the presence of oxygen atom. Then, the concentration of oxygen is determined from the current ILa and the density of water done in the form of current ILb-ILa. |
