来自臭氧-人类化学的纳米集群气溶主要由烯-臭氧反应主导
1Human-Oriented Built Environment Lab, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
概括
纳米集群气溶 (NCAs) 是由臭氧与人类皮肤脂质,主要是素反应而形成的. 较高的臭氧会增加NCA的形成,而氨会影响粒子大小和数量.
科学领域:
- 大气化学 大气化学
- 环境健康 环境健康
- 气溶科学 气溶科学
背景情况:
- 纳米集群气溶 (NCAs) 是与气候和健康相关的小颗粒 (<3 nm).
- 之前的研究表明,NCA是由臭氧与人体表面反应而形成的.
- 从人类表面发射NCA的机制以前是未知的.
研究的目的:
- 调查烯-臭氧反应在NCA形成中的作用.
- 为了确定不同臭氧和氨 (NH3) 度对NCA生产的影响.
主要方法:
- 控制的气候室实验.
- 玻璃表面上烯和6 - 六甲酸 (C16: 1n6) 的臭氧分解.
- 多样化的臭氧 (15,90ppb) 和氨 (0,375ppb) 的水平.
主要成果:
- 人体皮肤脂质的臭氧化产生NCA.
- 斯夸伦是主要的前体,产生的NCAs比C16:1n6.6多40倍.
- 更高的臭氧增加了NCA产量;更高的氨产生了更大的NCAs,但更少的小NCAs.
结论:
- 烯-臭氧反应是人类皮肤NCA的主要来源.
- 臭氧-人类表面化学是NCA形成的重要途径.
- 氨调节NCA的大小分布和数量.
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