单颗粒气溶胶飞行时间质谱可同时对气溶胶单颗粒的粒径大小、化学成分进行实时、在线检测.本研究介绍了新近研制的单颗粒质谱仪的原理、结构、主要技术指标及对香烟烟气气溶胶的应用研究.仪器采用空气动力学透镜聚焦,双光束粒径测量系统确定颗粒物的空气动力学直径,激光电离系统实现颗粒物精确电离,通过双极有网反射飞行时间质量分析器实现正负离子同时检测.香烟检测结果表明,在颗粒物粒径分布上,新鲜香烟烟气颗粒范围较老化烟气宽.在气溶胶化学成分上,老化烟气颗粒物与新鲜烟气相比,尼古丁,氰酸盐,硝酸盐,硫酸盐及铵盐5种成分的数浓度百分比都有所增加,而含C1-的数浓度百分比减少.原因可能是由于烟气由气相到粒相之间的转化,及颗粒物与空气中的气体发生了非均相反应；C1-老化之后的减少是因为HN03与CI-之间的非均相反应.%Single particle aerosol mass spectrometer (SPAMS) is an advanced instrument for simuta-neous detection of aerodynamic size and chemical composition of individual aerosol particles in real time. In this paper, the principle, configuration and features of our newly home-made SPAMS were described. Its application on the study of cigarette smoke aerosol analysis was also discussed. In SPAMS instrument, the aerodynamic focusing lens and double beam particle sizing system were used to measure particle's aerodynamic diameter; The laser ionization system realizes particle's accurately ionization and bipolar grid-reflection time-of-flight mass analyzer realizes simultaneous detection of positive and negative ions. The results indicate that the fresh cigarette smoke particles show a relatively broader size distribution, and in the aged smoke, the number fraction of containing nicotine, CN-, nitrate, sulfate and ammonium all increased compared with fresh smoke; in contrast, the number fraction of containing chloride reduced. This can be explained by the translation of gas phase to particle phase as well as the heterogeneous reactions between the gas and particles. The reason for the reduction of chloride may be due to the heterogeneous reactions between HNO3 and chloride.
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