| 摘要 |
PROBLEM TO BE SOLVED: To sensitively detect nitrogen oxide and nitric oxide contained in the exhaust gas of an internal combustion engine by a brownmillerite-type composite oxide as a detection element, by allowing a pair of metal electrodes to adhere to both the ends of the detection element, and by jointing a terminal conductor consisting of the same type of metal to the metal electrodes. SOLUTION: On both end faces of a detection element 10, a paste such as platinum is coated and backed for forming a pair of electrodes 4, and the electrodes 4 are connected to platinum terminal conductors 5 and 5a. To detect nitrogen oxide (NOx ) contained in the exhaust gas of an internal combustion engine, a protection pipe 6 is allowed to project toward the inside of the exhaust pipe through the pipe wall of an exhaust pipe, and a lid 7 and a flange are fixed onto the pipe wall. The exhaust gas flows from an inlet 9 to the inside of the protection pipe 6, collides with the surface of the detection element 10, and flows out to an outlet 9a. In this case, the detection element 10 mixes a blownmillerite powder with rhodium salt solution for calcining, thus obtaining a cylindrical calcination body. |
