改善城市环境呼唤加快天然气汽车的发展本刊记者李永增汽车与污染———现代化的矛盾轿车驶上京津塘高速公路。嘈杂、拥挤、污浊的闹市区快速向身后闪去。北京市自今年２月２７日开始发布空气质量周报，当时公布的空气污染指数显示，首都的空气质量已达中度污染程度，首要... Improve the urban environment calls for accelerating the development of natural gas vehicles Reporter Li Yongzeng Automobile and pollution --- the contradictions of modern cars sailed on the Beijing-Tianjin-Tanggu Expressway. Noisy, crowded, dirty downtown flash to the back quickly. Beijing Municipality released the weekly air quality report on February 27 this year. At that time, the air pollution index released showed that the air quality of the capital has reached a moderate degree of pollution, mainly ...