Non-volatile residuals of newly formed atmospheric particles in the boreal forest

摘要: The volatility of sub-micrometer atmospheric aerosol particles was studied in a rural background environment Finland using combination heating tube and scanning mobility particle sizer. analysis focused on nanoparticles formed through nucleation which were subsequently observed during their growth the diameter range between 5 60 nm. During 6 days new formation shown detail, concentrations newly increased up to 10 000 cm −3 . number mode measured after volatilization at 280°C 90% total under ambient conditions. Taking into account absolute accuracy size distribution measurements, all found atmosphere could have non-volatile core 280°C. As regional events developed over time as result further vapor condensation, grew an average rate 2.4±0.3 nm h −1 Importantly, cores also grow time, however, lower 0.6±0.3 One implication is that particles, reached diameters 15 nm, are unlikely consist sulfuric acid, ammonium sulfate, water alone. A relatively constant ratio well indicates matter only gradually growing particles. fraction showed some correlation with temperature. composition mechanism this material are, date, not known.