Kalberer, MarkusTabor, K.Ammann, MarkusParrat, YvesWeingartner, ErnestPiguet, D.Rössler, E.Jost, Dieter T.Türler, AndreasGäggeler, Heinz W.Baltensperger, Urs2024-08-222024-08-221996-09-190022-36541541-574010.1021/jp9606974https://irf.fhnw.ch/handle/11654/46915The heterogeneous reaction of NO2 with different carbon aerosol particles was investigated in situ. The NO2 was labeled with the β+-emitter 13N (half-life 10.0 min) which allowed application of NO2 at very low concentrations. The carbon aerosol was either produced by a spark discharge generator using graphite electrodes or by a brush generator resuspending commercial soot material. Monodisperse size cuts between 50- and 490-nm diameter were selected and mixed with the 13NO2. After a defined reaction time, the different reaction products were separated by means of selective traps and detected on-line by γ-spectrometry. A sticking coefficient for chemisorption of NO2 between 0.3 × 10ˉ⁴ and 4.0 × 10ˉ⁴ and a rate constant for the reduction of adsorbed NO2 to NO(g) between 4.0 × 10 ˉ⁴ and 9.4 × 10 ˉ⁴ /s were determined for both aerosols. The sticking coefficient obtained in this study in situ with aerosol particles is 2 orders of magnitudes smaller than the uptake coefficient recently reported with bulk carbon material.en550 - Geowissenschaften540 - Chemie01A - Beitrag in wissenschaftlicher Zeitschrift15487-15493