关键词: 气溶胶行为, 氡室, 沉降, 凝并, 浓度衰减

Abstract: Of all the dynamic processes in an enclosed and still radon chamber, deposition and coagulation of aerosol particles are the dominant processes on deciding aerosol activities. A simple experimental method to determine the corresponding coefficients of deposition and coagulation of aerosol particles was applied in our study. The result shows that as particle diameters increase from 58.7 to 436.4 nm, deposition coefficients decrease from 2.11×10^-5 s^-1 to 1.55×10^-5 (282.5 nm), then slowly increase to 1.72×10^-5 s^-1 and the coagulation coefficients decrease from 2.12×10^-9 cm³·s^-1 to 3.82×10^-10 cm³·s^-1. Compared with previous researches, they have the similar range of variation. In an environment with aerosol particle concentration of 10 000 cm^-3, the most stable particle size is 252.6 nm according to the decay rate influenced by both deposition and coagulation and it takes 40 min for the particle concentration to decrease by 5%. These data are valuable for the accurate control of aerosol and radon progeny in the radon chamber.

Key words: aerosol behavior, radon chamber, deposition and coagulation, concentration decay