[Characteristics and sources of elements of atmospheric particles before and in heating period in Beijing].

In order to study the characteristics and sources of atmospheric particles before and in heating period, samples of atmospheric particles were collected in November of 2006. Concentrations of elements in particles were determined with ICP-MS. The results shows that concentrations of As, Se, Mo, Cd in heating period are more than twice of those before heating period, and there is sharp increasing of concentrations of Zn, Pb, Tl, K, Se, As, Cu, Cd, Ag in fine particles in heating period. Furthermore, Zn, Na are associated with finer particles in heating period than those before heating period. Factor analysis on the chemical composition of particles shows that contribution of combustion and biomass burning goes up and contribution of crust goes down in heating period.