| Popis: |
The Changsha city of Hunan province was selected as study area to monitor the concentrations of PM2.5 and NO2 in ambient air automatically. The correlation relationship between PM2.5 and NO2 was also analyzed. Results showed that the concentrations of PM2.5 and NO2 changed significantly with seasons, and they manifested the same change trend, as winter > autumn > spring > concentration in summer. In a day, the lowest concentration of NO2 generally appeared in the afternoon. However, the present time of lowest and the peak values of PM2.5 concentration were uncertain. The highest concentration of NO2 was in the business district, and the distribution of PM2.5 concentration did not have an obviously regional. Furthermore, the PM2.5 and NO2 concentration changed in positive correlation, and these two were easy to produce pollution overlay. On the whole, the main seasons to control PM2.5 and NO2 were winter and autumn. |
