In a testing of petrolic engine, about 70% to 80% of nonmethane hydrocarbon is emitted into atmosphere without catalysis conversion in theoment of coldstart, so that serious pollution is produced.

在的一个测试循环中,约占排放污染物总量70%～80%的非甲烷碳氢合物是在冷起动阶段没有催转而直接排入大气中,造成严重污染。