TY  - JOUR
A1  - Berndt, Torsten
A1  - Stratmann, Frank
A1  - Sipilä, Mikko
A1  - Vanhanen, Joonas
A1  - Petäjä, Tuukka
A1  - Mikkilä, Jyri
A1  - Grüner, Achim
A1  - Spindler, Gerald
A1  - Mauldin, Roy Lee
A1  - Curtius, Joachim
A1  - Kulmala, Markku
A1  - Heintzenberg, Jost
T1  - Laboratory study on new particle formation from the reaction OH + SO2: influence of experimental conditions, H2O vapour, NH3 and the amine tert-butylamine on the overall process
T2  - Atmospheric chemistry and physics / Discussions
N2  - ucleation experiments starting from the reaction of OH radicals with SO2 have been performed in the IfT-LFT flow tube under atmospheric conditions at 293±0.5 K for a relative humidity of 13–61%. The presence of different additives (H2, CO, 1,3,5-trimethylbenzene) for adjusting the OH radical concentration and resulting OH levels in the range (4–300)·105 molecule cm−3 did not influence the nucleation process itself. The number of detected particles as well as the threshold H2SO4 concentration needed for nucleation was found to be strongly dependent on the counting efficiency of the used counting devices. High-sensitivity particle counters allowed the measurement of freshly nucleated particles with diameters down to about 1.5 nm. A parameterization of the experimental data was developed using power law equations for H2SO4 and H2O vapour. The exponent for H2SO4 from different measurement series was in the range of 1.7–2.1 being in good agreement with those arising from analysis of nucleation events in the atmosphere. For increasing relative humidity, an increase of the particle number was observed. The exponent for H2O vapour was found to be 3.1 representing a first estimate. Addition of 1.2·1011 molecule cm−3 or 1.2·1012 molecule cm−3 of NH3 (range of atmospheric NH3 peak concentrations) revealed that NH3 has a measureable, promoting effect on the nucleation rate under these conditions. The promoting effect was found to be more pronounced for relatively dry conditions. NH3 showed a contribution to particle growth. Adding the amine tert-butylamine instead of NH3, the enhancing impact for nucleation and particle growth appears to be stronger.
Y1  - 2010
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/29168
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-291680
SN  - 1680-7367
SN  - 1680-7375
N1  - © Author(s) 2010. This work is distributed under the Creative Commons Attribution 3.0 License.
VL  - 10
SP  - 6447
EP  - 6484
PB  - European Geosciences Union
CY  - Katlenburg-Lindau
ER  -