On the Microstructure of Different Types of Particles in PM10 in Beijing-Tianjin-Tangshan City Group Agglomeration Atmosphere

摘要

This paper analyses the microstructure of different types of particles in PM10 in Beijing-Tianjin-Tangshan urban agglomeration atmosphere in spring and summer by using field emission scanning electron microscopy (FESEM), in which the distribution characteristics of the size and number of the different types of particles in PM10 are specifically analyzed by using image analysis software. The research result shows that the types of particles in Beijing-Tianjin-Tangshan urban agglomeration atmosphere are unknown particles, soot aggregates, mineral particles and spherical particles. According to the proportion of the three partials in the atmosphere, the three cities ranks as follows: in the aspect of unknown particles, Tianjin ranks first, which is followed by Tangshan and Beijing; in the aspect of soot aggregates, Tangshan ranks first, which is followed by Beijing and Tianjin; in the aspect of mineral particles, Beijing ranks first, which is followed by Tangshan and Tianjin; in the aspect of spherical particles, Beijing ranks first, which is followed by Tangshan and Tianjin; Studies on single particles in atmosphere have always been an advanced part in particle research, which can provide information about the distribution, granularity size, components, sources and chemical reactions of PM. The electron microscope is an ideal machine to analyze single particles. Meanwhile, the chemical components, microstructure, granularity distribution of PM can be obtained with the help of X-ray energy spectrum. There were many researches studying the particles in Beijing and Tianjin, but those studies focused on only one or two particles. Besides, hardly anyone paid attention to Tangshan, a city in the middle of Beijing and Tianjin. All in all, there are no studies systematically comparing particles in PM10 of these three cities. Therefore, this paper analyses PM10 particle samples collected in the spring and summer of 2010 in Beijing, Tianjin, and Tangshan using FESEM and image analyzing tools and obtains the micro-morphology and distribution of PM10 particles in different seasons in different regions.