PAHs are in car or bus exhaust and emissions from residentialheating and power generation.
多环芳烃来自于汽车尾气以及住宅供暖和发电的排放。
2
Heat metering and energy efficiency renovations on existing residentialheating system in North China.
——北方采暖地区既有居住建筑供热计量及节能改造工作已经启动。
3
The residentialheating season is nearing its end, easing near-term demand for en plus grade pellets, which was pressuring industrial grade pellet availability.