diene value

例句：

1. 1.The diene value of the oil is 40%.
   该油的二烯值是40%。
2. 2. The increase in diene value indicates a decrease in the amount of unsaturated compounds.
   二烯值的增加表明不饱和化合物的量在减少。
3. 3.The diene value is an important indicator of the quality of the petroleum.
   二烯值是衡量石油质量的重要指标。