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Full-Text Articles in Physics
Isoprene Suppression Of New Particle Formation In A Mixed Deciduous Forest, V. P. Kanawade, B. T. Jobson, A. B. Guenther, M. E. Erupe, S. N. Pressley, S. N. Tripathi, Shan-Hu Lee
Isoprene Suppression Of New Particle Formation In A Mixed Deciduous Forest, V. P. Kanawade, B. T. Jobson, A. B. Guenther, M. E. Erupe, S. N. Pressley, S. N. Tripathi, Shan-Hu Lee
Shan-Hu Lee
Production of new particles over forests is an important source of cloud condensation nuclei that can affect climate. While such particle formation events have been widely observed, their formation mechanisms over forests are poorly understood. Our observations made in a mixed deciduous forest with large isoprene emissions during the summer displayed a surprisingly rare occurrence of new particle formation (NPF). Typically, NPF events occur around noon but no NPF events were observed during the 5 weeks of measurements. The exceptions were two evening ultrafine particle events. During the day, sulfuric acid concentrations were in the 106 cm−3 range with very …
The Effect Of Trimethylamine On Atmospheric Nucleation Involving H2so4, M. E. Erupe, A. A. Viggiano, Shan-Hu Lee
The Effect Of Trimethylamine On Atmospheric Nucleation Involving H2so4, M. E. Erupe, A. A. Viggiano, Shan-Hu Lee
Shan-Hu Lee
Field observations and quantum chemical calculations have shown that organic amine compounds may be important for new particle formation involving H2SO4. Here, we report laboratory observations that investigate the effect of trimethylamine (TMA) on H2SO4-H2O nucleation made under aerosol precursor concentrations typically found in the lower troposphere ([H2SO4] of 106−107 cm−3; [TMA] of 180–1350 pptv). The threshold [H2SO4] needed to produce the unity J was from 106−107 cm−3 and the slopes of Log …
New Particle Growth And Shrinkage Observed In Subtropical Environments, L. H. Young, Shan-Hu Lee, V. P. Kanawade, T-C. Hsiao, Y. L. Lee, B-F. Hwang, Y-J. Liou, H-T. Hsu, P-J. Tsai
New Particle Growth And Shrinkage Observed In Subtropical Environments, L. H. Young, Shan-Hu Lee, V. P. Kanawade, T-C. Hsiao, Y. L. Lee, B-F. Hwang, Y-J. Liou, H-T. Hsu, P-J. Tsai
Shan-Hu Lee
We present the first systematic analysis for new particle formation (NPF), growth and shrinkage of new particles at four different sites in subtropical central Taiwan. A total of 14 NPF events were identified from 137 days of ambient measurements during a cold and warm season. The measured formation rates of 10 nm particles (J10) and growth rates were in the range of 4.4–30 cm−3s−1 and 7.4–24 nm h−1, respectively. The onset of NPF events coincided with decreases of condensation sink (CS) and increases of SO2 under enhanced atmospheric mixing and dilution. …