在柴油车辆排放羽毛中,多环芳和多环芳的变化
Hongqian Che1, Xianbao Shen2, Jiacheng Shi3
1Department of Environmental Science and Engineering, Beijing Technology and Business University, Beijing 100048, China; School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China.
Journal of hazardous materials
|June 14, 2025
概括
柴油排气显示多环芳 (PAHs) 和酸PAHs (NPAHs) 从气相转变为稀释后的粒子相. 这些化合物对二次有机碳 (SOC) 形成有重大贡献,影响空气质量.
科学领域:
- 环境化学环境化学
- 大气科学 大气科学
- 燃烧科学 燃烧科学
背景情况:
- 多环芳 (PAHs) 和型PAHs (NPAHs) 是具有不利健康影响的重要空气污染物.
- 了解它们的大气行为,特别是在车辆排气中,对于有效的污染控制策略至关重要.
- 柴油排放是PAHs和NPAHs的主要来源,需要详细描述它们在排气中的命运.
研究的目的:
- 为了研究柴油车辆排气中PAH和NPAH的气体颗粒分离行为.
- 分析车辆类型,排放标准和运行条件对PAH和NPAH大气行为的影响.
- 量化PAHs和NPAHs在羽毛稀释过程中对二次有机碳 (SOC) 形成的贡献.
主要方法:
- 在各种运行条件下对21辆柴油车进行现实测试.
- 在不同采样点的废气羽毛中描述了PAHs和NPAHs的气体和颗粒相.
- 分析了PAHs,NPAHs,二氧化碳 (CO2) 和二次有机碳 (SOC) 形成之间的关系.
主要成果:
- 与二氧化碳相对的PAH和NPAH总量在排气中保持稳定,但组成分布有所变化.
- 随着羽毛稀释,PAHs和NPAHs的粒子相百分比显著增加,表明气体到粒子相转换.
- 多氧化和不多氧化对SOC形成做出了重大贡献,在稀释过程中观察到的最大比例.
结论:
- 羽毛稀释促进了PAHs和NPAHs从气体到粒子阶段的相位过渡.
- 多氧化和非氧化是柴油废气中二次有机碳 (SOC) 形成的重要前体.
- 结果为大气建模提供经验数据,并为控制空气污染中PAH,NPAH和SOC的战略提供信息.
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