在美国,如果您鸳驶以汽油为动力的车辆,您一定可以放心地从各地加油站获得具合适辛烷值的汽油。例如,操作手册上规定用91号汽油,您便可以确信所加的就是91号汽油,而不会是87号或89号。之所以有这种安全感是因为多数州都定期对加油站进行检查,以确定其所售汽油是否货真价实。但是,如果您驾驶的是以压缩天然气(CNG)为动力的车辆又如何呢?在天然气的加工过程中,重烃类组分被除去以调节气体混合物的能量含量,而天然气不能像汽油那样被精炼。因此,对轻烃类组分只能进行有限的控制。天然气车辆在燃料含能量过高、过低或成分变化过大时不能正常工 In the United States, if you are traveling on a gasoline-powered vehicle, you can be assured of getting the right octane for your gas station. For example, if it is stipulated in the operation manual to use gasoline No. 91, you can be sure that the added gasoline is No. 91 instead of No. 87 or No. 89. The reason for this sense of security is that most states check gas stations on a regular basis to determine if the gas they sell is genuine. But what if you are driving on CNG-powered vehicles? During natural gas processing heavy hydrocarbon components are removed to regulate the energy content of the gas mixture, which can not be as gasoline Refined. Therefore, there is only limited control over light hydrocarbon components. Natural gas vehicles can not work normally when the fuel contains too much energy, too low or the composition changes too much