Fig. 1. Structure of detecting system

Fig. 2. Changes of parameters with time

Fig. 3. Changes of parameters with time

Fig. 4. Vertical distribution of atmospheric transmittance at 12:30 on February 2, 2018

Fig. 5. Comparison of vertical distribution of atmospheric transmittance at 15 in February 10, 2018

Fig. 6. Comparison of vertical distribution of PM2.5 mass concentration at 15 in February 10, 2018

Fig. 7. Vertical inversion of PM2.5 mass concentration

Fig. 8. HYSPLIT backward trajectory