References

ACPD

Atmospheric Chemistry and Physics Discussions

ACPD

1680-7375

Copernicus GmbH

Göttingen, Germany

10.5194/acpd-12-11415-2012

Particle hygroscopicity during atmospheric new particle formation events: implications for the chemical species contributing to particle growth

¹ Birmili

¹ Poulain

¹ Merkel

¹ Fahlbusch

¹ van Pinxteren

¹ Herrmann

¹ Wiedensohler

Leibniz Institute for Tropospheric Research, Permoserstraße 15, 04318 Leipzig, Germany

03 05 2012

12 5 11415 11443

This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

This article is available from http://www.atmos-chem-phys-discuss.net/12/11415/2012/acpd-12-11415-2012.html

The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/12/11415/2012/acpd-12-11415-2012.pdf

This study examines the hygroscopicity of newly formed particles (smaller than 50 nm in particle mobility diameter) during two atmospheric new particle formation events with and without clear growth process at mid-level mountain range in Central Germany based on HCCT field campaign. Particle hygroscopicity measurements show that the particle soluble fractions at the end of event for two events are, respectively 60% (45 nm particles for the event with clear growth) and 20% (30 nm particles for the event without clear growth), stressing that non-soluble organic compounds may play a key role in particle growth during new particle formation event. Such significant difference in particle hygroscopicity also suggests that the chemical species responsible for nucleation particle growth are considerably different between the two selected NPF events. During both events, the hygroscopicity of newly formed particles decreased with particle growth, indicating that more less-hygroscopic compounds contribute to the subsequent condensation in contrast to the earlier stage. Sulfuric acid was considered to be responsible of the NPF event and represent the highly hygroscopic compounds. However, calculation demonstrated that sulfuric acid condensation failed to fully explain the observed soluble fraction in the nucleation mode particles. Therefore, we hypothesize that some water-soluble matters may explain the missing soluble fraction.

References 1

Asmi,~E., Frey,~A., Virkkula,~A., Ehn,~M., Manninen,~H E., Timonen,~H., Tolonen-Kivimäk,~O., Aurela,~M., Hillamo,~R., and Kulmala,~M.: Hygroscopicity and chemical composition of antarctic sub-micrometre aerosol particles and observations of new particle formation, Atmos. Chem. Phys., 10, 4253–4271, http://dx.doi.org/10.5194/acp-10-4253-2010doi:10.5194/acp-10-4253-2010, 2010.

Barsanti,~K C., McMurry,~P H., and Smith,~J N.: The potential contribution of organic salts to new particle growth, Atmos. Chem. Phys., 9, 2949–2957, http://dx.doi.org/10.5194/acp-9-2949-2009doi:10.5194/acp-9-2949-2009, 2009.

Birmili,~W., Berresheim,~H., Plass-Dülmer,~C., Elste,~T., Gilge,~S., Wiedensohler,~A., and Uhrner,~U.: The hohenpeissenberg aerosol formation experiment (hafex): a~long-term study including size-resolved aerosol, \chemH_2SO_4, OH, and monoterpenes measurements, Atmos. Chem. Phys., 3, 361–376, http://dx.doi.org/10.5194/acp-3-361-2003doi:10.5194/acp-3-361-2003, 2003.

Boy,~M., Kulmala,~M., Ruuskanen,~T M., Pihlatie,~M., Reissell,~A., Aalto,~P P., Keronen,~P., Dal~Maso,~M., Hellen,~H., Hakola,~H., Jansson,~R., Hanke,~M., and Arnold,~F.: Sulphuric acid closure and contribution to nucleation mode particle growth, Atmos. Chem. Phys., 5, 863–878, http://dx.doi.org/10.5194/acp-5-863-2005doi:10.5194/acp-5-863-2005, 2005.

ten Brink,~H., Otjes,~R., Jongejan,~P., and Slanina,~S.: An instrument for semi-continuous monitoring of the size-distribution of nitrate, ammonium, sulphate and chloride in aerosol, Atmos. Environ., 41, 2768–2779, http://dx.doi.org/10.1016/j.atmosenv.2006.11.041doi:10.1016/j.atmosenv.2006.11.041, 2007.

Brus,~D., Neitola,~K., Hyvärinen,~A P., Petäjä,~T., Vanhanen,~J., Sipilä,~M., Paasonen,~P., Kulmala,~M., and Lihavainen,~H.: Homogenous nucleation of sulfuric acid and water at close to atmospherically relevant conditions, Atmos. Chem. Phys., 11, 5277–5287, http://dx.doi.org/10.5194/acp-11-5277-2011doi:10.5194/acp-11-5277-2011, 2011.

Dal Maso,~M., Kulmala,~M., Riipinen,~I., Wagner,~R., Hussein~T., Aalto,~P P., and Lehtinen,~A K E J.: Formation and growth of fresh atmospheric aerosols: eight years of aerosol size distribution data from SMEAR II, Hyytiälä, Finland, Boreal Environ. Res., 10, 323–336, 2005.

DeCarlo,~P F., Kimmel,~J R., Trimborn,~A., Northway,~M J., Jayne,~J T., Aiken,~A C., Gonin,~M., Fuhrer,~K., Horvath,~T., Docherty,~K S., Worsnop,~D R., and Jimenez,~J L.: Field-deployable, high-resolution, time-of-flight aerosol mass spectrometer, Anal. Chem., 78, 8281–8289, http://dx.doi.org/10.1021/ac061249ndoi:10.1021/ac061249n, 2006.

Draxier,~R R. and Hess,~G D.: An overview of the HYSPLIT_4 modelling system for trajectories, dispersion and deposition, Aust. Meteorol. Mag., 47, 295–308, 1998.

Ehn,~M., Petäjä,~T., Aufmhoff,~H., Aalto,~P., Hämeri,~K., Arnold,~F., Laaksonen,~A., and Kulmala,~M.: Hygroscopic properties of ultrafine aerosol particles in the boreal forest: diurnal variation, solubility and the influence of sulfuric acid, Atmos. Chem. Phys., 7, 211–222, http://dx.doi.org/10.5194/acp-7-211-2007doi:10.5194/acp-7-211-2007, 2007.

Gysel,~M., McFiggans,~G B., and Coe,~H.: Inversion of tandem differential mobility analyser (TDMA) measurements, J. Aerosol Sci., 40, 134–151, 2009.

Hämeri,~K., Väkevä,~M., Aalto,~P P., Kulmala,~M., Swietlicki,~E., Zhou,~J., Seidl,~W., Becker,~E., and O'Dowd,~C D.: Hygroscopic and ccn properties of aerosol particles in boreal forests, Tellus B, 53, 359–379, http://dx.doi.org/10.1034/j.1600-0889.2001.530404.xdoi:10.1034/j.1600-0889.2001.530404.x, 2001.

Herrmann,~H., Wolke,~R., Müller,~K., Brüggemann,~E., Gnauk,~T., Barzaghi,~P., Mertes,~S., Lehmann,~K., Massling,~A., Birmili,~W., Wiedensohler,~A., Wieprecht,~W., Acker,~K., Jaeschke,~W., Kramberger,~H., Svrcina,~B., Bächmann,~K., Collett Jr,~J L., Galgon,~D., Schwirn,~K., Nowak,~A., van Pinxteren,~D., Plewka,~A., Chemnitzer,~R., Rüd,~C., Hofmann,~D., Tilgner,~A., Diehl,~K., Heinold,~B., Hinneburg,~D., Knoth,~O., Sehili,~A M., Simmel,~M., Wurz\hackler,~S., Majdik,~Z., Mauersberger,~G., and Müller,~F.: Febuko and modmep: field measurements and modelling of aerosol and cloud multiphase processes, Atmos. Environ., 39, 4169–4183, http://dx.doi.org/10.1016/j.atmosenv.2005.02.004doi:10.1016/j.atmosenv.2005.02.004, 2005.

Kiendler-Scharr,~A., Wildt,~J., Maso,~M D., Hohaus,~T., Kleist,~E., Mentel,~T F., Tillmann,~R., Uerlings,~R., Schurr,~U., and Wahner,~A.: New particle formation in forests inhibited by isoprene emissions, Nature, 461, 381–384, 2009.

Kulmala,~M., Maso,~M D., MäKelä,~J M., Pirjola,~L., VäKevä,~M., Aalto,~P., Miikkulainen,~P., Hämeri,~K., and O'Dowd,~C D.: On the formation, growth and composition of nucleation mode particles, Tellus B, 53, 479–490, http://dx.doi.org/10.1034/j.1600-0889.2001.530411.xdoi:10.1034/j.1600-0889.2001.530411.x, 2001.

Kulmala,~M., Laakso,~L., Lehtinen,~K E J., Riipinen,~I., Dal Maso,~M., Anttila,~T., Kerminen,~V M., Hõrrak,~U., Vana,~M., and Tammet,~H.: Initial steps of aerosol growth, Atmos. Chem. Phys., 4, 2553–2560, http://dx.doi.org/10.5194/acp-4-2553-2004doi:10.5194/acp-4-2553-2004, 2004a.

Kulmala,~M., Vehkamäki,~H., Petäjä,~T., Dal Maso,~M., Lauri,~A., Kerminen,~V M., Birmili,~W., and McMurry,~P H.: Formation and growth rates of ultrafine atmospheric particles: a~review of observations, J. Aerosol Sci., 35, 143–176, http://dx.doi.org/10.1016/j.jaerosci.2003.10doi:10.1016/j.jaerosci.2003.10, 2004b.

Kulmala,~M., Petäjä,~T., Mönkkönen,~P., Koponen,~I K., Dal Maso,~M., Aalto,~P P., Lehtinen,~K E J., and Kerminen,~V M.: On the growth of nucleation mode particles: source rates of condensable vapor in polluted and clean environments, Atmos. Chem. Phys., 5, 409–416, http://dx.doi.org/10.5194/acp-5-409-2005doi:10.5194/acp-5-409-2005, 2005.

Kulmala,~M., Lehtinen,~K E J., and Laaksonen,~A.: Cluster activation theory as an explanation of the linear dependence between formation rate of 3nm particles and sulphuric acid concentration, Atmos. Chem. Phys., 6, 787–793, http://dx.doi.org/10.5194/acp-6-787-2006doi:10.5194/acp-6-787-2006, 2006.

Kulmala,~M., Arola,~A., Nieminen,~T., Riuttanen,~L., Sogacheva,~L., de Leeuw,~G., Kerminen,~V M., and Lehtinen,~K E J.: The first estimates of global nucleation mode aerosol concentrations based on satellite measurements, Atmos. Chem. Phys., 11, 10791–10801, http://dx.doi.org/10.5194/acp-11-10791-2011doi:10.5194/acp-11-10791-2011, 2011.

Laaksonen,~A., Hamed,~A., Joutsensaari,~J., Hiltunen,~L., Cavalli,~F., Junkermann,~W., Asmi,~A., Fuzzi,~S., and Facchini,~M C.: Cloud condensation nucleus production from nucleation events at a~highly polluted region, Geophys. Res. Lett., 32, L06812, http://dx.doi.org/10.1029/2004gl022092doi:10.1029/2004gl022092, 2005.

Lee,~K W., Chen,~J., and Gieseke,~J A.: Log-normally preserving size distribution for brownian coagulation in the free-molecule regime, Aerosol Sci. Technol., 3, 53–62, http://dx.doi.org/10.1080/02786828408958993doi:10.1080/02786828408958993, 1984.

Lee,~K W., Curtis,~L A., and Chen,~H.: An analytic solution to free molecule aerosol coagulation, Aerosol Sci. Technol., 12, 457–462, http://dx.doi.org/10.1080/02786829008959360doi:10.1080/02786829008959360, 1990.

Malm,~W C. and Kreidenweis,~S M.: The effects of models of aerosol hygroscopicity on the apportionment of extinction, Atmos. Environ., 31, 1965–1976, http://dx.doi.org/10.1016/s1352-2310(96)00355-xdoi:10.1016/s1352-2310(96)00355-x, 1997.

Maßling,~A., Wiedensohler,~A., Busch,~B., Neusüß,~C., Quinn,~P., Bates,~T., and Covert,~D.: Hygroscopic properties of different aerosol types over the Atlantic and Indian Oceans, Atmos. Chem. Phys., 3, 1377–1397, http://dx.doi.org/10.5194/acp-3-1377-2003doi:10.5194/acp-3-1377-2003, 2003.

Massling,~A., Leinert,~S., Wiedensohler,~A., and Covert,~D.: Hygroscopic growth of sub-micrometer and one-micrometer aerosol particles measured during ACE-Asia, Atmos. Chem. Phys., 7, 3249–3259, http://dx.doi.org/10.5194/acp-7-3249-2007doi:10.5194/acp-7-3249-2007, 2007.

Massling,~A., Niedermeier,~N., Hennig,~T., Fors,~E O., Swietlicki,~E., Ehn,~M., Hämeri,~K., Villani,~P., Laj,~P., Good,~N., McFiggans,~G., and Wiedensohler,~A.: Results and recommendations from an intercomparison of six Hygroscopicity-TDMA systems, Atmos. Meas. Tech., 4, 485–497, http://dx.doi.org/10.5194/amt-4-485-2011doi:10.5194/amt-4-485-2011, 2011.

Mikkonen,~S., Romakkaniemi,~S., Smith,~J N., Korhonen,~H., Petäjä,~T., Plass-Duelmer,~C., Boy,~M., McMurry,~P H., Lehtinen,~K E J., Joutsensaari,~J., Hamed,~A., Mauldin~III,~R L., Birmili,~W., Spindler,~G., Arnold,~F., Kulmala,~M., and Laaksonen,~A.: A~statistical proxy for sulphuric acid concentration, Atmos. Chem. Phys., 11, 11319–11334, http://dx.doi.org/10.5194/acp-11-11319-2011doi:10.5194/acp-11-11319-2011, 2011.

Modini,~R L., Ristovski,~Z D., Johnson,~G R., He,~C., Surawski,~N., Morawska,~L., Suni,~T., and Kulmala,~M.: New particle formation and growth at a~remote, sub-tropical coastal location, Atmos. Chem. Phys., 9, 7607–7621, http://dx.doi.org/10.5194/acp-9-7607-2009doi:10.5194/acp-9-7607-2009, 2009.

Petäjä,~T., Kerminen,~V M., Dal Maso,~M., Junninen,~H., Koponen,~I K., Hussein,~T., Aalto,~P P., Andronopoulos,~S., Robin,~D., Hämeri,~K., Bartzis,~J G., and Kulmala,~M.: Sub-micron atmospheric aerosols in the surroundings of marseille and athens: physical characterization and new particle formation, Atmos. Chem. Phys., 7, 2705–2720, http://dx.doi.org/10.5194/acp-7-2705-2007doi:10.5194/acp-7-2705-2007, 2007.

Pierce,~J R., Riipinen,~I., Kulmala,~M., Ehn,~M., Petäjä,~T., Junninen,~H., Worsnop,~D R., and Donahue,~N M.: Quantification of the volatility of secondary organic compounds in ultrafine particles during nucleation events, Atmos. Chem. Phys., 11, 9019–9036, http://dx.doi.org/10.5194/acp-11-9019-2011doi:10.5194/acp-11-9019-2011, 2011.

Ristovski,~Z D., Suni,~T., Kulmala,~M., Boy,~M., Meyer,~N K., Duplissy,~J., Turnipseed,~A., Morawska,~L., and Baltensperger,~U.: The role of sulphates and organic vapours in growth of newly formed particles in a eucalypt forest, Atmos. Chem. Phys., 10, 2919–2926, http://dx.doi.org/10.5194/acp-10-2919-2010doi:10.5194/acp-10-2919-2010, 2010.

Sakurai,~H., Fink,~M A., McMurry,~P H., Mauldin,~L., Moore,~K F., Smith,~J N., and Eisele,~F L.: Hygroscopicity and volatility of 4–10 \unitnm particles during summertime atmospheric nucleation events in urban atlanta, J. Geophys. Res., 110, D22S04, http://dx.doi.org/10.1029/2005jd005918doi:10.1029/2005jd005918, 2005.

Sipilä,~M., Berndt,~T., Petäjä,~T., Brus,~D., Vanhanen,~J., Stratmann,~F., Patokoski,~J., Mauldin,~R L., Hyvärinen,~A.-P., Lihavainen,~H., and Kulmala,~M.: The role of sulfuric acid in atmospheric nucleation, Science, 327, 1243–1246, 2010.

Smith,~J N., Moore,~K F., McMurry,~P H., and Eisele,~F L.: Atmospheric measurements of sub-20 \unitnm diameter particle chemical composition by thermal desorption chemical ionization mass spectrometry, Aerosol Sci. Technol., 38, 100–110, http://dx.doi.org/10.1080/02786820490249036doi:10.1080/02786820490249036, 2004.

Smith,~J N., Moore,~K F., Eisele,~F L., Voisin,~D., Ghimire,~A K., Sakurai,~H., and McMurry,~P H.: Chemical composition of atmospheric nanoparticles during nucleation events in atlanta, J. Geophys. Res., 110, D22S03, http://dx.doi.org/10.1029/2005jd005912doi:10.1029/2005jd005912, 2005.

Smith,~J N., Barsanti,~K C., Friedli,~H R., Ehn,~M., Kulmala,~M., Collins,~D R., Scheckman,~J H., Williams,~B J., and and McMurry,~P H.: Observations of aminium salts in atmospheric nanoparticles and possible climatic implications, P. Natl. Acad. Sci. USA, 107, 6634–6639, 2010.

Spracklen,~D V., Carslaw,~K S., Kulmala,~M., Kerminen,~V.-M., Sihto,~S.-L., Riipinen,~I., Merikanto,~J., Mann,~G W., Chipperfield,~M P., Wiedensohler,~A., Birmili,~W., and Lihavainen,~H.: Contribution of particle formation to global cloud condensation nuclei concentrations, Geophys. Res. Lett., 35, L06808, http://dx.doi.org/10.1029/2007gl033038doi:10.1029/2007gl033038, 2008.

Stokes,~R H. and Robinson,~R A.: Interactions in aqueous nonelectrolyte solutions. I. Solute-solvent equilibria, J. Phys. Chem., 70, 2126–2130, 1966.

Stolzenburg,~M R., McMurry,~P H., Sakurai,~H., Smith,~J N., Mauldin III,~R L., Eisele,~F L., and Clement,~C F.: Growth rates of freshly nucleated atmospheric particles in atlanta, J. Geophys. Res., 110, D22S05, http://dx.doi.org/10.1029/2005jd005935doi:10.1029/2005jd005935, 2005.

Swietlicki,~E., Zhou,~J., Berg,~O H., Martinsson,~B G., Frank,~G., Cederfelt,~S I., Dusek,~U., Berner,~A., Birmili,~W., Wiedensohler,~A., Yuskiewicz,~B., and Bower,~K N.: A~closure study of sub-micrometer aerosol particle hygroscopic behaviour, Atmos. Res., 50, 205–240, http://dx.doi.org/10.1016/s0169-8095(98)00105-7doi:10.1016/s0169-8095(98)00105-7, 1999.

Tang,~I N. and Munkelwitz,~H R.: Water activities, densities, and refractive indices of aqueous sulfates and sodium nitrate droplets of atmospheric importance, J. Geophys. Res., 99, 18801–18808, http://dx.doi.org/10.1029/94jd01345doi:10.1029/94jd01345, 1994.

Väkevä,~M., Kulmala,~M., Stratmann,~F., and Hämeri,~K.: Field measurements of hygroscopic properties and state of mixing of nucleation mode particles, Atmos. Chem. Phys., 2, 55–66, http://dx.doi.org/10.5194/acp-2-55-2002doi:10.5194/acp-2-55-2002, 2002.

Varutbangkul,~V., Brechtel,~F J., Bahreini,~R., Ng,~N L., Keywood,~M D., Kroll,~J H., Flagan,~R C., Seinfeld,~J H., Lee,~A., and Goldstein,~A H.: Hygroscopicity of secondary organic aerosols formed by oxidation of cycloalkenes, monoterpenes, sesquiterpenes, and related compounds, Atmos. Chem. Phys., 6, 2367–2388, http://dx.doi.org/10.5194/acp-6-2367-2006doi:10.5194/acp-6-2367-2006, 2006.

Virkkula,~A., Van Dingenen,~R., Raes,~F., and Hjorth,~J.: Hygroscopic properties of aerosol formed by oxidation of limonene, α-pinene, and β-pinene, J. Geophys. Res., 104, 3569–3579, http://dx.doi.org/10.1029/1998jd100017doi:10.1029/1998jd100017, 1999.

Wang,~L., Khalizov,~A F., Zheng,~J., Xu,~W., Ma,~Y., Lal,~V., and Zhang,~R.: Atmospheric nanoparticles formed from heterogeneous reactions of organics, Nature Geosci., 3, 238–242, 2010.

Wang,~M. and Penner,~J E.: Aerosol indirect forcing in a~global model with particle nucleation, Atmos. Chem. Phys., 9, 239–260, http://dx.doi.org/10.5194/acp-9-239-2009doi:10.5194/acp-9-239-2009, 2009.

Wehner,~B., Petäjä,~T., Boy,~M., Engler,~C., Birmili,~W., Tuch,~T., Wiedensohler,~A., and Kulmala,~M.: The contribution of sulfuric acid and non-volatile compounds on the growth of freshly formed atmospheric aerosols, Geophys. Res. Lett., 32, L17810, http://dx.doi.org/10.1029/2005gl023827doi:10.1029/2005gl023827, 2005.

Wiedensohler,~A., Cheng,~Y F., Nowak,~A., Wehner,~B., Achtert,~P., Berghof,~M., Birmili,~W., Wu,~Z J., Hu,~M., Zhu,~T., Takegawa,~N., Kita,~K., Kondo,~Y., Lou,~S R., Hofzumahaus,~A., Holland,~F., Wahner,~A., Gunthe,~S S., Rose,~D., Su,~H., and Pöschl,~U.: Rapid aerosol particle growth and increase of cloud condensation nucleus activity by secondary aerosol formation and condensation: a~case study for regional air pollution in Northeastern China, J. Geophys. Res., 114, D00G08, http://dx.doi.org/10.1029/2008jd010884doi:10.1029/2008jd010884, 2009.

Wiedensohler,~A., Birmili,~W., Nowak,~A., Sonntag,~A., Weinhold,~K., Merkel,~M., Wehner,~B., Tuch,~T., Pfeifer,~S., Fiebig,~M., Fjäraa,~A M., Asmi,~E., Sellegri,~K., Depuy,~R., Venzac,~H., Villani,~P., Laj,~P., Aalto,~P., Ogren,~J A., Swietlicki,~E., Williams,~P., Roldin,~P., Quincey,~P., Hüglin,~C., Fierz-Schmidhauser,~R., Gysel,~M., Weingartner,~E., Riccobono,~F., Santos,~S., Gröning,~C., Faloon,~K., Beddows,~D., Harrison,~R., Monahan,~C., Jennings,~S G., O'Dowd,~C D., Marinoni,~A., Horn,~H.-G., Keck,~L., Jiang,~J., Scheckman,~J., McMurry,~P H., Deng,~Z., Zhao,~C S., Moerman,~M., Henzing,~B., de~Leeuw,~G., Löschau,~G., and Bastian,~S.: Mobility particle size spectrometers: harmonization of technical standards and data structure to facilitate high quality long-term observations of atmospheric particle number size distributions, Atmos. Meas. Tech., 5, 657–685, http://dx.doi.org/10.5194/amt-5-657-2012doi:10.5194/amt-5-657-2012, 2012.

Wu,~Z J., Nowak,~A., Poulain,~L., Herrmann,~H., and Wiedensohler,~A.: Hygroscopic behavior of atmospherically relevant water-soluble carboxylic salts and their influence on the water uptake of ammonium sulfate, Atmos. Chem. Phys., 11, 12617–12626, http://dx.doi.org/10.5194/acp-11-12617-2011doi:10.5194/acp-11-12617-2011, 2011.

Yue,~D L., Hu,~M., Zhang,~R Y., Wang,~Z B., Zheng,~J., Wu,~Z J., Wiedensohler,~A., He,~L Y., Huang,~X F., and Zhu,~T.: The roles of sulfuric acid in new particle formation and growth in the mega-city of Beijing, Atmos. Chem. Phys., 10, 4953–4960, http://dx.doi.org/10.5194/acp-10-4953-2010doi:10.5194/acp-10-4953-2010, 2010.

Yue,~D L., Hu,~M., Zhang,~R Y., Wu,~Z J., Su,~H., Wang,~Z B., Peng,~J F., He,~L Y., Huang,~X F., Gong,~Y G., and Wiedensohler,~A.: Potential contribution of new particle formation to cloud condensation nuclei in beijing, Atmos. Environ., 45, 6070–6077, http://dx.doi.org/10.1016/j.atmosenv.2011.07.037doi:10.1016/j.atmosenv.2011.07.037, 2011.

Zdanovskii,~B.: Novyi metod rascheta rastvorimostei elektrolitov v mnogokomponentnykh sistema, Zh. Fiz. Khim+, 22, 1478–1485, 1486–1495, 1948.

Zhang,~Q., Stanier,~C O., Canagaratna,~M R., Jayne,~J T., Worsnop,~D R., Pandis,~S N., and Jimenez,~J L.: Insights into the chemistry of new particle formation and growth events in pittsburgh based on aerosol mass spectrometry, Environ. Sci. Technol., 38, 4797–4809, http://dx.doi.org/10.1021/es035417udoi:10.1021/es035417u, 2004a.

Zhang,~R., Suh,~I., Zhao,~J., Zhang,~D., Fortner,~E C., Tie,~X., Molina,~L T., and Molina,~M J.: Atmospheric new particle formation enhanced by organic acids, Science, 304, 1487–1490, http://dx.doi.org/10.1126/science.1095139doi:10.1126/science.1095139, 2004b.

Zhang,~Q., Jimenez,~J L., Worsnop,~D R., and Canagaratna,~M.: A~case study of urban particle acidity and its influence on secondary organic aerosol, Environ. Sci. Technol., 41, 3213–3219, http://dx.doi.org/10.1021/es061812jdoi:10.1021/es061812j, 2007.

Zhang,~Y M., Zhang,~X Y., Sun,~J Y., Lin,~W L., Gong,~S L., Shen,~X J., and Yang,~S.: Characterization of new particle and secondary aerosol formation during summertime in Beijing, China, Tellus B, 63, 382–394, http://dx.doi.org/10.1111/j.1600-0889.2011.00533.xdoi:10.1111/j.1600-0889.2011.00533.x, 2011.