题目: 汽油机产生爆震的原因是什么? 答案: 参考答案:1)与燃料性质有关,如果燃料很容易氧化,形成过氧化物不易分解,自燃点低,就很容易爆震。2)与发动机工作条件有关,如果发动机压缩比大,气缸温度高,或操作不当,都易产生爆震现象
题型:选择题 Many new means__________ to prevent the river ____________.A.have found, from pollutingB.have found, from being pollutedC.have been found, from being pollutedD.has been found, from being polluted 查看答案