Fushimi Akihiro, Fujitani Yuji, Durdina Lukas, Anet Julien G, Spirig Curdin, Edebeli Jacinta, Sakurai Hiromu, Murashima Yoshiko, Saitoh Katsumi, Takegawa Nobuyuki
Health and Environmental Risk Division, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan.
Centre for Aviation, Zurich University of Applied Sciences, Technikumstrasse 9, PO Box CH-8401, Winterthur 8401, Switzerland.
ACS EST Air. 2025 Apr 8;2(5):847-856. doi: 10.1021/acsestair.4c00309. eCollection 2025 May 9.
The impact of aircraft exhaust particles on human health and climate are raising concerns globally. Particle number concentrations in exhaust plumes of turbofan jet engines, which are commonly used in civil aviation, are generally dominated by volatile particles (sulfates or organics) rather than nonvolatile particles (mostly soot). However, the mechanism of emission and formation of volatile particles are unclear. Here, we evaluated the exhaust particles from turbofan engines at the engine exit and downstream. In downstream samples, the number of soot particles with scattering-layered graphene-like structures, typically generated by combustion, was <1% of the total number of particles analyzed. The remaining fraction predominantly contained trace amorphous, amorphous, and onion-like particles that partially contain graphene-like circular layers. The microphysical structures of these three types of particles in aircraft exhaust plumes were newly identified. They were mainly single spherical particles with diameters of ∼10-20 nm, suggesting that they were formed via nucleation and partial pyrolysis and were not significantly affected by coagulation with preexisting soot particles. The unique internal structures of these particles may affect their physicochemical properties, including volatility, surface reactivity, and solubility, and potentially impact their interaction with the human respiratory tract.
飞机尾气颗粒对人类健康和气候的影响正引起全球关注。民航常用的涡轮风扇喷气发动机尾气羽流中的颗粒数浓度通常以挥发性颗粒（硫酸盐或有机物）为主，而非挥发性颗粒（主要是烟灰）。然而，挥发性颗粒的排放和形成机制尚不清楚。在此，我们评估了涡轮风扇发动机在发动机出口和下游的尾气颗粒。在下游样本中，具有典型燃烧产生的散射层状类石墨烯结构的烟灰颗粒数量占分析颗粒总数的比例不到1%。其余部分主要包含微量无定形、无定形和洋葱状颗粒，其中部分含有类石墨烯圆形层。飞机尾气羽流中这三种类型颗粒的微观物理结构是新发现的。它们主要是直径约为10 - 20纳米的单个球形颗粒，这表明它们是通过成核和部分热解形成的，并且与预先存在的烟灰颗粒的凝聚作用对其影响不大。这些颗粒独特的内部结构可能会影响它们的物理化学性质，包括挥发性、表面反应性和溶解性，并可能影响它们与人类呼吸道的相互作用。
