| 摘要 |
An internal combustion engine with a catalyst-containing exhaust-gas aftertreatment device is lubricated with a composition of a base oil; and a zinc salt of a mixture of phosphorus-containing compounds having hydrocarbyl groups R1 and R2 where the average total number of carbon atoms in R1 plus R2 for the mixture of phosphorus-containing compounds is at least 9.5, where 4 to 30 weight percent of such groups contain 2 to 4 carbon atoms and where in less than 8 mole percent of the phosphorus-containing molecules in the mixture of phosphorus-containing compounds each of R1 and R2 contain 2 to 4 carbon atoms. |
