Ion and nano-particle measurement in ion-induced nucleation process

Ion-induced nucleation is the process leading supersaturated vapors to condense on ions and has become an attractive research subject to understand the gas-to-particle conversion process involving generation of ions and nanometer sized particles (nano-particles). In order to measure the mobility distribution of ions and nano-particles in the ion-induced nucleation process, the current aerosol measurement technology has been recently improved. The performance of these methods was confirmed by measuring the electrical mobility distribution of water ions generated by various methods. Ion-induced nucleation experiments using these improved aerosol measurement capabilities were performed for the following two cases: (1) condensation of supersaturated vapors onto monovalent and divalent ions of varying size, and (2) ion and nano-particle formation from SO2, NO2, H2O, NH3 and air mixture by ionizing irradiation. The results clearly show that ion-induced nucleation depends greatly on the sign of ion, ion size, type of vapor and supersaturation ratio.