汽车制动是高电荷气溶颗粒的来源
Adam E Thomas1, Paulus S Bauer1, Michelia Dam1
1Department of Chemistry, University of California, Irvine, CA 92697.
概括
车磨损颗粒 (BWPs) 是越来越重要的空气污染物. 这项研究显示,高达80%的BWP具有电荷,材料类型会影响电荷. 了解BWP收费是空气质量洞察的关键.
科学领域:
- 环境科学 环境科学
- 大气化学 大气化学
- 材料科学 材料科学 材料科学
背景情况:
- 非排气排放,如车和轮胎磨损,是交通相关颗粒物污染的日益增长的来源.
- 汽车车片的磨损对非废气颗粒质量有显著的贡献,这一趋势预计将随着汽车电气化而增加.
研究的目的:
- 研究来自陶和半金属制动片的制动磨损颗粒 (BWPs) 的电性能.
- 了解充电机制和BWP对大气命运和空气质量的影响.
主要方法:
- 陶和半金属制动片的BWP排放.
- 在排放的BWP上测量电荷.
- 分析电荷极性,大小,以及对粒子大小和制动片材料的依赖.
主要成果:
- 发现高达80%的排放BWP是电充电的.
- 充电BWP的比例因车片的材料而异.
- 粒子表现出正负电荷,持有30多个基本电荷,产生了更多负电荷的证据.
结论:
- 车磨损颗粒具有显著的电荷,受材料组成的影响.
- 了解BWP收费机制对于评估其大气寿命以及对空气质量和气候的影响至关重要.
- 水器的电气性能为开发排放控制策略提供了潜力.
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