Profiling Aerosol Particles In Regional Atmospheric Boundary Layer With Single Particle Analysis

The size, morphology, composition, and mixing state of aerosol particles in the regional atmospheric boundary layer were analyzed with TEM and ESEM/EDX. In Beijing and at the top of Mt. Tai, the air quality and weather conditions changed remarkably during the passage of the cold cyclones, and morphological characteristics of soot particles were similar in prefrontal and postfrontal airs, suggesting that soot particles aged quickly in the relative clean postfrontal air. "Si rich" mineral particles in the prefrontal air (36.1%) was lower than in the postfrontal air (50.6%) in Beijing, and the main types at Mt. Tai were "S rich" mineral particles in the prefrontal air and "Si rich" mineral particles in the postfrontal air. The sulfate on mineral particles in the prefrontal air was obviously higher than in the postfrontal air, which implied that the atmospheric processing can modify the morphology and composition of mineral particles in cold cyclones. In Beijing, an elevated aerosol layer (EAL) was encountered at the altitude of 700-1000 m with the tethered balloon system. Soot particles in EAL were well aged and spherical with the size range of 0.2-1.3?m, suggesting that the increase of accumulation mode particles in elevated layers in polluted urban atmosphere was not always due to new particle formtaion. The hygroscopicity of mineral particles and soot particles were not obvious in the dust source areas, and the soot particles were in aged status also.