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| cycle | sample | starting time | end time | single-way lifetime (month) |
| 1 | industrial cat. | 2012.8.20 | 2013.2.29 | 6.3 |
| 2 | first-regenerated | 2013.9.18 | 2014.3.29 | 6.3 |
| 3 | second-regenerated | 2014.12.20 | 2015.7.15 | 6.8 |
