| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a catalyst for treating nitrogen oxides, which is used for directly decomposing nitrogen oxides, particularly, NO contained in exhaust gas to be discharged from an external-combustion engine and the deterioration of whose catalytic activity due to the O<SB>2</SB>to be generated by decomposition or the O<SB>2</SB>coexisting in exhaust gas is made extremely lower. <P>SOLUTION: The catalyst for treating nitrogen oxides is composed of oxides of rare earth metals or a compound oxide of rare earth metals, each of which has a cubic C-type structure. <P>COPYRIGHT: (C)2007,JPO&INPIT |
