Study On Monitoring The Inhalable Particulate Matters In Typical Areas In Nanjing

The concentration of the inhalable particulate matters (PM₁₀) was measured by the portable DustTrak Aerosol Monitor-8520 from October 2005 to April 2006, at the span of the human breathing in the air of the typical areas in Nanjing City. The variational orderliness and influencing factors of the concentration were also intensively studied. It turns out that the PM₁₀ concentration is the lowest in winter; it's close in spring and autumn. In a day, the maximum PM₁₀ concentration in the street comes out at about 8 a.m., it is different from that in residential area, which comes out at about 10 a.m., and the minimum at about 4 p.m. The concentration in Zijin Moutain Area is the lowest in all typical areas. By measuring the concentration and the influencing factors in the streets, it's indicated that the types of the vehicles and the meteorologic conditions are the two most notable influencing factors. Among the meteorologic conditions, the influence of cloudage and humidity are most notable, then the influence of wind speed, which is much complex. The forecast model of the streets in spring was established using the multiple regress model by studying up on the Guanghua Street. Through the influencing factors, such as cloudage, humidity, wind speed, the PM₁₀ concentration can be estimated facilely. The study indicated that the tunnel has the effect of accumulating pollutant. Using atmospheric diffusion equation, the model of the PM₁₀ concentration for roadway tunnel was developed, based on the study of the Xuanwu Lake Tunnel. The computational results of the model are close to those of the experiments.