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在道路微环境中对流和分散变化的综合实地研究
Sheng Xiang1,2, Shaojun Zhang3,4,5, Peter Brimblecombe6,7
1State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai, China 200092, P.R.China.
Environmental science & technology
|October 5, 2024
概括
科学家们发现,动动能 (TKE) 和来自车辆的污染物分散 (D) 之间存在着强烈的联系. 这种TKE-D关系有助于高精度地确定交通排放热点.
科学领域:
- 环境科学 环境科学
- 大气化学 大气化学
- 运输工程 运输工程
背景情况:
- 与交通有关的空气污染物 (TRAP) 由于车辆排放的分散而带来暴露风险.
- 准确识别TRAP排放热点对于风险评估至关重要.
研究的目的:
- 调查动动能 (TKE) 和污染物分散 (D) 之间的关系.
- 开发一个现场验证的TKE-D模型,用于估计车辆排放量和识别热点.
主要方法:
- 进行了为期五年的近路采样活动和道路采样活动.
- 根据车辆的排放和度,测量TKE和计算污染物分散 (D).
- 收集了198个近路和377个路上测量对进行分析.
主要成果:
- 观察到TKE和D与道路附近的车辆流量之间存在正相关性 (R2 ≥0.69).
- 在道路上的测量显示了类似的衰变模式和车型对TKE和D的敏感性.
- 开发了一个强大的TKE-D关系,具有强烈的相关性 (R2 ≥0.61) 和一致的斜率 (1.1-1.3).
结论:
- 现场证据证实了TKE和D之间的积极关联,独立于测量方法或位置.
- 该TKE-D关系允许使用TKE作为唯一输入的车辆排放估计.
- 便利交通排放热点的高时空分辨率识别.
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