随着经济的发展,在用机动车辆数量猛增,以上海市为例,目前登记上牌照的车辆已经超过60万辆,加上摩托车和助力车总数已经达到130万辆。上海市城区机动车辆有害成分年排放量CO达19.6万t,HC达4.77万t,NO_x达4.96万t。监测表明,机动车辆排放污染物已经成为城市大气的主要污染源。据有关资料统计,美国在用车中,有3％排放特别差的车辆排放的污 With economic development, the number of motor vehicles soars. Taking Shanghai as an example, the number of vehicles currently registered with the license has exceeded 600,000. Together with the total number of motorcycles and mopeds, the number has reached 1.3 million. The annual emissions of harmful components of motor vehicles in Shanghai urban area reached 196,000 tons, the number of HC reached 47,700 tons, and the NO_x reached 49,600 tons. Monitoring shows that the emission of pollutants by motor vehicles has become the major source of pollution to the urban atmosphere. According to statistics, the United States in the car, there are 3% of the emissions of particularly poor emissions of vehicles