| 摘要 |
<p>PROBLEM TO BE SOLVED: To accurately evaluate the degree of heat deterioration or of poisoning deterioration of an exhaust emission control catalyst. SOLUTION: An actual NOx purification factor is obtained of an NOx absorbent 12 to determine the amount of SOx absorbed by the NOx absorbent 12. A reference NOx purification factor of the NOx absorbent 12 is obtained when it is assumed that the NOx absorbent 12 is not thermally deteriorated based on the amount of SOx absorbed. When the actual NOx purification factor of the NOx absorbent 12 is smaller than the reference NOx purification factor, the NOx absorbent 12 is determined to be thermally deteriorated.</p> |
