1Department of Atmospheric Physics, Saint-Petersburg University, St. Petersburg State University, SPbSU, SPbU, 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
2Biogeochemistry and Multiphase Chemistry Departments, Max Planck Institute for Chemistry, P.O. Box 3060, 55020 Mainz, Germany
3Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093, USA
Received: 22 Jul 2016 – Discussion started: 23 Sep 2016
Abstract. A tandem arrangement of Differential Mobility Analyser and Humidified Centrifugal Particle Mass Analyser (DMA-HCPMA) was developed to measure the deliquescence and efflorescence thresholds and the water uptake of submicron particles over the relative humidity (RH) range from 10 to 95 %. The hygroscopic growth curves obtained for ammonium sulfate and sodium chloride test aerosols are consistent with thermodynamic model predictions and literature data. The DMA-HCPMA system was applied to measure the hygroscopic properties of urban aerosol particles, and the kappa mass interaction model (KIM) was used to characterize and parameterize the concentration-dependent water uptake observed in the 50–95 % RH range. For DMA-selected 160 nm dry particles (modal mass of 3.5 fg), we obtained a volume-based hygroscopicity parameter, κv ≈ 0.2, which is consistent with literature data for freshly emitted urban aerosols.
Revised: 02 Feb 2017 – Accepted: 03 Mar 2017 – Published: 30 Mar 2017
Overall, our results show that the DMA-HCPMA system can be used to measure size-resolved mass growth factors of atmospheric aerosol particles upon hydration and dehydration up to 95 % RH. Direct measurements of particle mass avoid the typical complications associated with the commonly used mobility-diameter-based HTDMA technique (mainly due to poorly defined or unknown morphology and density).
Vlasenko, S. S., Su, H., Pöschl, U., Andreae, M. O., and Mikhailov, E. F.: Tandem configuration of differential mobility and centrifugal particle mass analysers for investigating aerosol hygroscopic properties, Atmos. Meas. Tech., 10, 1269-1280, doi:10.5194/amt-10-1269-2017, 2017.