| Abstract [eng] |
Physical and chemical properties of the submicron range (PM1) volatile and semi-volatile atmospheric aerosol particles that influence their evolution are examine in the dissertation. It is shown that organics comprise a significant fraction (68.8 % - 77.1 %) of the total measured PM1 at the background (Rūgšteliškio Research station, Preila Research station) and the urban areas (Vilnius) during the mild season, respectively. The origin of organics is identified using Positive Matrix Factorization method. The influence of long-range transport air masses for PM1 components (sulfates, nitrates, ammonium, chloride and organics) mass concentration is evaluated. The contribution of ammonium nitrate and ammonium sulfate out of all sulfates and nitrates is estimated. The method for estimation of PM1 organics density distribution within aerosol particles for data simultaneously obtained with Q-AMS and SMPS is developed. Presented method has shown that particles (with diameter less than 100 nm) tend to form aggregates and have different effective matter density less than 1 g cm-3 at an urban site during formation under the influence of intensive transport emission. Analysis of the extent of acidic sulfate neutralization with atmospheric ammonia has shown that particles tend to be fully neutralized when their size is of about tenths of nanometers, whereas the larger particles have a lower extent of neutralization in volcanic origin aerosol particles. |
