| 摘要 |
PURPOSE:To detect stably nitrogen oxide with good reproducibility by covering one of poroud electrodes with a porous catalyst layer consisting of a nitrogen oxide adsorp tive material to form an oxygen concn. cell and measuring the electromotive force thereof. CONSTITUTION:NO is adsorbed into the catalyst layer 3 consisting essentially of Fe3O4 and the oxidation reaction 2NO+O2 2NO2 progresses if a detector is placed in a gas contg. NO. Then the oxygen partial pressure on the electrode 2a side covered with the catalyst layer decreases as compared to the electrode 2b side. On the other hand, the migration of oxygen ions from the side where the oxygen partial pressure is high toward the side where the oxygen partial pressure is low arises in the zirconia solid electrode at the psecified temp. or above. The electromotive force calculated with the equation is generated between the electrodes 2a, 2b as the oxygen cell. Here, R, T, F denote respectively a gas constant, absolute temp. and Faraday constant, Po2(I) denotes the oxygen partial pressure on the electrode 2b side where the oxygen partial pressure is high and Po2(II) denotes the oxygen partial pressure on the electrode 2a side covered with the catalyst where the oxygen partial pressure is low. The electro motive force E is detected by a voltmeter 5 and the concn. of NO is detected from the prescribed concn. of NO and the electromotive force E. |
