Secondary organic aerosol tracers and malic acid in Hong Kong: seasonal trends and origins
Di Hu A B D and Jian Zhen Yu C
+ Author Affiliations
- Author Affiliations
A Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Kowloon, Hong Kong, P. R. China.
B HKBU Institute of Research and Continuing Education, Shenzhen Virtual University Park, Shenzhen, 518057, P. R. China.
C Department of Chemistry and Division of Environment, Hong Kong University of Science & Technology, Clear Water Bay, Kowloon, Hong Kong, P. R. China.
D Corresponding author. Email: dihu@hkbu.edu.hk
Environmental Chemistry 10(5) 381-394 https://doi.org/10.1071/EN13104
Submitted: 5 June 2013 Accepted: 26 August 2013 Published: 22 October 2013
Environmental context. Secondary organic aerosols (SOAs), a major organic component of ambient fine particles, contribute to adverse health effects and visibility degradation. Quantification of SOA tracers allows estimation of contributions from specific precursors, which helps the formulation of effective control strategies. We found that malic acid was present in SOA at high abundance in both winter and summer; its seasonally distinct inter-species relationships offer insights into distinct SOA formation pathways.
Abstract. Fine particle samples collected at an urban location in Hong Kong during winter were analysed by gas chromatography–ion trap mass spectrometry with prior chemical derivatisation. In total, 15 secondary organic aerosol (SOA) tracers from isoprene, monoterpenes, β-caryophyllene and toluene, and 24 other polar oxygenated compounds, were identified and quantified. Monoterpenes and isoprene SOA tracers showed lower levels on winter long-range transport (LRT) days than summer regional days, the latter being reported in our previous study. Opposite seasonal trends were observed for SOA tracers of β-caryophyllene and toluene. The averaged total secondary organic carbon (SOC) apportioned to these four volatile organic compounds (VOCs) was estimated to be 4.73 μg C m–3 on winter LRT days, lower than that on summer regional days (5.21 μg C m–3). β-caryophyllene and monoterpenes were found to be the most significant SOC contributors to PM2.5 in Hong Kong in both winter and summer, and their averaged SOC contributions on winter LRT days were 2.24 and 1.59 μg C m–3. Toluene and isoprene had relatively minor contributions to SOC in Hong Kong in both seasons, with averaged SOC contributions of 0.81 and 0.08 μg C m–3 on winter LRT days. Malic acid was well correlated with biogenic SOA tracers and oxalate in both seasons, whereas correlation between malic and succinic acid was only found in winter. Based on the seasonal characteristic inter-species correlations in the region, we hypothesise that malic acid could be formed mainly by the aqueous-phase photodegradation of SOA products of biogenic VOCs during summer. In winter, emissions of biogenic VOCs are greatly reduced and succinic acid then becomes the predominant contributor to malic acid.
References
[1] T. E. Kleindienst, M. Jaoui, M. Lewandowski, J. H. Offenberg, C. W. Lewis, P. V. Bhave, E. O. Edney, Estimates of the contributions of biogenic and anthropogenic hydrocarbons to secondary organic aerosol at a southeastern US location. Atmos. Environ. 2007, 41, 8288.| Estimates of the contributions of biogenic and anthropogenic hydrocarbons to secondary organic aerosol at a southeastern US location.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXhtlWntrjJ&md5=0dcfb3871c51e5d4a661c177c693e912CAS |
[2] D. Hu, Q. Bian, T. W. Y. Li, A. K. H. Lau, J. Z. Yu, Contributions of isoprene, monoterpenes, β-caryophyllene, and toluene to secondary organic aerosols in Hong Kong during the summer of 2006. J. Geophys. Res. 2008, 113, D22206.
| Contributions of isoprene, monoterpenes, β-caryophyllene, and toluene to secondary organic aerosols in Hong Kong during the summer of 2006.Crossref | GoogleScholarGoogle Scholar |
[3] W. Wang, M. H. Wu, L. Li, T. Zhang, H. J. Li, Y. J. Wang, X. D. Liu, G. Y. Sheng, M. Claeys, J. M. Fu, Polar organic tracers in PM2.5 aerosols from forests in eastern China. Atmos. Chem. Phys. 2008, 8, 7507.
| Polar organic tracers in PM2.5 aerosols from forests in eastern China.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXhslejs70%3D&md5=41367d8f479a0481ad49838b54b77f3dCAS |
[4] X. Ding, X.-M. Wang, B. Gao, X.-X. Fu, Q.-F. He, X.-Y. Zhao, J.-Z. Yu, M. Zheng, Tracer-based estimation of secondary organic carbon in the Pearl River Delta, south China. J. Geophys. Res. 2012, 117, D05313.
| Tracer-based estimation of secondary organic carbon in the Pearl River Delta, south China.Crossref | GoogleScholarGoogle Scholar |
[5] M. Lewandowski, M. Jaoui, J. H. Offenberg, T. E. Kleindienst, E. O. Edney, R. J. Sheesley, J. J. Schauer, Primary and secondary contributions to ambient PM in the midwestern United States. Environ. Sci. Technol. 2008, 42, 3303.
| Primary and secondary contributions to ambient PM in the midwestern United States.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXktVarsLg%3D&md5=533d4e651d9e14191db959eababe59f1CAS | 18522110PubMed |
[6] I. Kourtchev, J. Warnke, W. Maenhaut, T. Hoffmann, M. Claeys, Polar organic marker compounds in PM2.5 aerosol from a mixed forest site in western Germany. Chemosphere 2008, 73, 1308.
| Polar organic marker compounds in PM2.5 aerosol from a mixed forest site in western Germany.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXhtlSgsL%2FK&md5=02ba17e5ef3a62c8c5297511bdfeede9CAS | 18710779PubMed |
[7] I. Kourtchev, L. Copolovici, M. Claeys, W. Maenhaut, Characterization of atmospheric aerosols at a forested site in central Europe. Environ. Sci. Technol. 2009, 43, 4665.
| Characterization of atmospheric aerosols at a forested site in central Europe.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXjtlOgtbc%3D&md5=77eeba6bec8cda7e338da5f8e47e8505CAS | 19673249PubMed |
[8] I. El Haddad, N. Marchand, B. Temime-Roussel, H. Wortham, C. Piot, J. L. Besombes, C. Baduel, D. Voisin, A. Armengaud, J. L. Jaffrezo, Insights into the secondary fraction of the organic aerosol in a Mediterranean urban area: Marseille. Atmos. Chem. Phys. 2011, 11, 2059.
| Insights into the secondary fraction of the organic aerosol in a Mediterranean urban area: Marseille.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXpslylsLs%3D&md5=8abb0c352eae58a3536e9d2e140b9ce4CAS |
[9] D. Hu, Q. Bian, A. K. H. Lau, J. Z. Yu, Source apportioning of primary and secondary organic carbon in summer PM2.5 in Hong Kong using positive matrix factorization of secondary and primary organic tracer data. J. Geophys. Res. 2010, 115, D16204.
| Source apportioning of primary and secondary organic carbon in summer PM2.5 in Hong Kong using positive matrix factorization of secondary and primary organic tracer data.Crossref | GoogleScholarGoogle Scholar |
[10] K. Kawamura, K. Ikushima, Seasonal changes in the distribution of dicarboxylic acids in the urban atmosphere. Environ. Sci. Technol. 1993, 27, 2227.
| Seasonal changes in the distribution of dicarboxylic acids in the urban atmosphere.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3sXlsVGnt78%3D&md5=5abffe4312c91a2addf5ccf954cc6206CAS |
[11] K. Kawamura, F. Sakaguchi, Molecular distributions of water soluble dicarboxylic acids in marine aerosols over the Pacific Ocean including tropics. J. Geophys. Res. 1999, 104, 3501.
| Molecular distributions of water soluble dicarboxylic acids in marine aerosols over the Pacific Ocean including tropics.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1MXitFWjs7o%3D&md5=66feff0f3ea47de4c7555782c74c3c22CAS |
[12] W. F. Rogge, L. M. Hildemann, M. A. Mazurek, G. R. Cass, B. R. T. Simoneit, Sources of fine organic aerosol. 9. Pine, oak, and synthetic log combustion in residential fireplaces. Environ. Sci. Technol. 1998, 32, 13.
| Sources of fine organic aerosol. 9. Pine, oak, and synthetic log combustion in residential fireplaces.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXnsFOmurc%3D&md5=7cb3293cad85038f17a79728af71c950CAS |
[13] K. Kawamura, I. R. Kaplan, Motor exhaust emissions as a primary source for dicarboxylic acids in Los Angeles ambient air. Environ. Sci. Technol. 1987, 21, 105.
| Motor exhaust emissions as a primary source for dicarboxylic acids in Los Angeles ambient air.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2sXit1Giuw%3D%3D&md5=c4d859b4edd1e4a0b778eec31a3a9264CAS |
[14] J. J. Schauer, M. J. Kleeman, G. R. Cass, B. R. T. Simoneit, Measurement of emission from air pollution sources. 4. C1–C27 organic compounds from cooking with seed oils. Environ. Sci. Technol. 2002, 36, 567.
| Measurement of emission from air pollution sources. 4. C1–C27 organic compounds from cooking with seed oils.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXptlCit7Y%3D&md5=e7c39581486d0ab04c3783de69953425CAS | 11883419PubMed |
[15] M. Claeys, B. Graham, G. Vas, W. Wang, R. Vermeylen, V. Pashynska, J. Cafmeyer, P. Guyon, M. O. Andreae, P. Artaxo, W. Maenhaut, Formation of secondary organic aerosols through photooxidation of isoprene. Science 2004, 303, 1173.
| Formation of secondary organic aerosols through photooxidation of isoprene.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXhsVWgtb4%3D&md5=0738273575454fede931b49bcec741d0CAS | 14976309PubMed |
[16] P. Fu, K. Kawamura, K. Okuzawa, S. G. Aggarwal, G. Wang, Y. Kanaya, Z. Wang, Organic molecular compositions and temporal variations of summertime mountain aerosols over Mt. Tai, North China Plain. J. Geophys. Res. 2008, 113, D19107.
| Organic molecular compositions and temporal variations of summertime mountain aerosols over Mt. Tai, North China Plain.Crossref | GoogleScholarGoogle Scholar |
[17] B. Graham, O. L. Mayol-Bracero, P. Guyon, G. C. Roberts, S. Decesari, M. C. Facchini, P. Artaxo, W. Maenhaut, P. Koll, M. O. Andreae, Water-soluble organic compounds in biomass burning aerosols over Amazonia 1. Characterization by NMR and GC-MS. J. Geophys. Res. 2002, 107, D208047.
| Water-soluble organic compounds in biomass burning aerosols over Amazonia 1. Characterization by NMR and GC-MS.Crossref | GoogleScholarGoogle Scholar |
[18] K. Kawamura, O. Yasui, Diurnal changes in the distribution of dicarboxylic acids, ketocarboxylic acids and dicarbonyl in the urban Tokyo atmosphere. Atmos. Environ. 2005, 39, 1945.
| Diurnal changes in the distribution of dicarboxylic acids, ketocarboxylic acids and dicarbonyl in the urban Tokyo atmosphere.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXitlSlu78%3D&md5=51edead356062b7e5dff726284c9d45dCAS |
[19] M. Li, S. R. McDow, D. J. Tollerud, M. A. Mazurek, Seasonal abundance of organic molecular markers in urban particulate matter from Philadelphia, PA. Atmos. Environ. 2006, 40, 2260.
| Seasonal abundance of organic molecular markers in urban particulate matter from Philadelphia, PA.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28Xit1agtrk%3D&md5=4c73bfb446e1242bcd39bd50d0217b42CAS |
[20] M. E. Birch, R. A. Cary, Elemental carbon-based method for monitoring occupational exposures to particulate diesel exhaust. Aerosol Sci. Technol. 1996, 25, 221.
| Elemental carbon-based method for monitoring occupational exposures to particulate diesel exhaust.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK28XlvFOkt78%3D&md5=3f5189f140541b7f645b0bfe86574369CAS |
[21] J. J. Schauer, B. T. Mader, J. T. DeMinter, G. Heidemann, M. S. Bae, J. H. Seinfeld, R. C. Flagan, R. A. Cary, D. Smith, B. J. Huebert, T. Bertram, S. Howell, J. T. Kline, P. Quinn, T. Bates, B. Turpin, H. J. Lim, J. Z. Yu, H. Yang, M. D. Keywood, ACE-Asia intercomparison of a thermal-optical method for the determination of particle-phase organic and elemental carbon. Environ. Sci. Technol. 2003, 37, 993.
| ACE-Asia intercomparison of a thermal-optical method for the determination of particle-phase organic and elemental carbon.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXltlOitQ%3D%3D&md5=9144c204aad25e39a362b25dd6c821cfCAS | 12666931PubMed |
[22] H. Yang, J. Z. Yu, S. S. H. Ho, J. Xu, W. S. Wu, C. H. Wan, X. Wang, X. Wang, L. Wang, The chemical composition of inorganic and carbonaceous materials in PM2.5 in Nanjing, China. Atmos. Environ. 2005, 39, 3735.
| The chemical composition of inorganic and carbonaceous materials in PM2.5 in Nanjing, China.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXlt1WmsLc%3D&md5=5c866d861af50f644394f2dbe2ffaefdCAS |
[23] T. Wang, C. N. Poon, Y. H. Kwok, Y. S. Li, Characterizing the temporal variability and emission patterns of pollution plumes in the Pearl River Delta of China. Atmos. Environ. 2003, 37, 3539.
| Characterizing the temporal variability and emission patterns of pollution plumes in the Pearl River Delta of China.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXltFCls78%3D&md5=21a3c3ecd3de384c2a3518f25442a865CAS |
[24] R. K. Pathak, X. H. Yao, A. K. H. Lau, C. K. Chan, Acidity and concentrations of ionic species of PM2.5 in Hong Kong. Atmos. Environ. 2003, 37, 1113.
| Acidity and concentrations of ionic species of PM2.5 in Hong Kong.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXhtlGrtbs%3D&md5=11cfe675beeb3d0e1ccc0256b46d8a56CAS |
[25] J. Xue, A. K. H. Lau, J. Z. Yu, A study of acidity on PM2.5 in Hong Kong using online ionic chemical composition measurements. Atmos. Environ. 2011, 45, 7081.
| A study of acidity on PM2.5 in Hong Kong using online ionic chemical composition measurements.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXhtlyjur%2FE&md5=d83608585cd4d8aae41720d76cb16f4bCAS |
[26] J. D. Surratt, M. Lewandowski, J. H. Offenberg, M. Jaoui, T. E. Kleindienst, E. O. Edney, J. H. Seinfeld, Effect of acidity on secondary organic aerosol formation from isoprene. Environ. Sci. Technol. 2007, 41, 5363.
| Effect of acidity on secondary organic aerosol formation from isoprene.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXmvFeisrc%3D&md5=cd8084de82802e8be5d31e2c14cb2263CAS | 17822103PubMed |
[27] X. Ding, X.-M. Wang, M. Zheng, The influence of temperature and aerosol acidity on biogenic secondary organic aerosol tracers: observations at rural site in the central Pearl River Delta region, South China. Atmos. Environ. 2011, 45, 1303.
| The influence of temperature and aerosol acidity on biogenic secondary organic aerosol tracers: observations at rural site in the central Pearl River Delta region, South China.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXhvVWrsLk%3D&md5=10e13ccd9e2349c7e3987cc5ee66c3beCAS |
[28] D. Y. C. Leung, P. Wong, B. K. H. Cheung, A. Guenther, Improved land cover and emission factors for modeling biogenic volatile organic compounds emissions from Hong Kong. Atmos. Environ. 2010, 44, 1456.
| Improved land cover and emission factors for modeling biogenic volatile organic compounds emissions from Hong Kong.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXjtFKmsLk%3D&md5=f118248adb471b746c5368c39c1a8410CAS |
[29] F. Paulot, J. D. Crounse, H. G. Kjaergaard, A. Kurten, J. M. St. Clair, J. H. Seinfeld, P. O. Wennberg, Unexpected epoxide formation in the gas-phase photooxidation of isoprene. Science 2009, 325, 730.
| Unexpected epoxide formation in the gas-phase photooxidation of isoprene.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXptl2gurs%3D&md5=f2962a0866fbdfd48efdc2b4c081b352CAS | 19661425PubMed |
[30] E. C. Minerath, M. J. Elrod, Assessing the potential for diol and hydroxy sulfate ester formation from the reaction of epoxides in tropospheric aerosols. Environ. Sci. Technol. 2009, 43, 1386.
| Assessing the potential for diol and hydroxy sulfate ester formation from the reaction of epoxides in tropospheric aerosols.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXht1OhsLg%3D&md5=dffd654069928a4db2d23a6300befb41CAS | 19350908PubMed |
[31] W. Wang, I. Kourtchev, B. Graham, J. Cafmeyer, W. Maenhaut, M. Claeys, Characterization of oxygenated derivatives of isoprene related to 2-methyltetrols in Amazonian aerosols using trimethylsilylation and gas chromatography/ion trap mass spectrometry. Rapid Commun. Mass Spectrom. 2005, 19, 1343.
| Characterization of oxygenated derivatives of isoprene related to 2-methyltetrols in Amazonian aerosols using trimethylsilylation and gas chromatography/ion trap mass spectrometry.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXkvVyqsLk%3D&md5=9aac589eadb3dcb8d40a438076ff2b53CAS | 15856536PubMed |
[32] M. Claeys, R. Szmigielski, I. Kourtchev, P. V. D. Veken, R. Vermeylen, W. Maenhaut, M. Jaoui, T. E. Kleindienst, M. Lewandowski, J. H. Offenberg, E. O. Edney, Hydroxydicarboxylic acids: markers for secondary organic aerosol from the photooxidation of α-Pinene. Environ. Sci. Technol. 2007, 41, 1628.
| Hydroxydicarboxylic acids: markers for secondary organic aerosol from the photooxidation of α-Pinene.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXns1OltA%3D%3D&md5=94b0a63f6316cf2cfb51f79aeed2da44CAS | 17396652PubMed |
[33] J. H. Offenberg, M. Lewandowski, E. O. Edney, T. E. Kleindienst, M. Jaoui, Influence of aerosol acidity on the formation of secondary organic aerosol from biogenic precursor hydrocarbons. Environ. Sci. Technol. 2009, 43, 7742.
| Influence of aerosol acidity on the formation of secondary organic aerosol from biogenic precursor hydrocarbons.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXhtFGiu7rI&md5=3ee15418e8d662ad33c434b7f742e506CAS | 19921888PubMed |
[34] Y. Shu, R. Atkinson, Atmospheric lifetimes and fates of a series of sesquiterpenes. J. Geophys. Res. 1995, 100, 7275.
| Atmospheric lifetimes and fates of a series of sesquiterpenes.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXmt1Chsbc%3D&md5=82602c194881102fb1e2cb5a75916dc7CAS |
[35] M. Jaoui, S. Leungsakul, R. M. Kamens, Gas and particle products distribution from the reaction of β-caryophyllene with ozone. J. Atmos. Chem. 2003, 45, 261.
| Gas and particle products distribution from the reaction of β-caryophyllene with ozone.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXks1Cnt7w%3D&md5=46e37340a873c17fc0a6f6328a8697a4CAS |
[36] M. Jaoui, M. Lewandowski, T. E. Kleindienst, J. H. Offenberg, E. O. Edney, β-caryophyllinic acid: an atmospheric tracer for β-caryophyllene secondary organic aerosol. Geophys. Res. Lett. 2007, 34, L05816.
| β-caryophyllinic acid: an atmospheric tracer for β-caryophyllene secondary organic aerosol.Crossref | GoogleScholarGoogle Scholar |
[37] E. S. C. Kwok, R. Atkinson, Estimation of hydroxyl radical reaction rate constants for gas-phase organic compounds using a structure-reactivity relationship: an update. Atmos. Environ. 1995, 29, 1685.
| Estimation of hydroxyl radical reaction rate constants for gas-phase organic compounds using a structure-reactivity relationship: an update.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXmvFCms70%3D&md5=fb28d7e29756c5f9a16e407c80314a3fCAS |
[38] A. K. H. Lau, Z. Yuan, J. Z. Yu, P. K. K. Louie, Source apportionment of ambient volatile organic compounds in Hong Kong. Sci. Total Environ. 2010, 408, 4138.
| Source apportionment of ambient volatile organic compounds in Hong Kong.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXptVWnsLc%3D&md5=156eb4ae14b158315193233fdb67c5d8CAS |
[39] L. Y. Chan, K. W. Chu, S. C. Zou, C. Y. Chan, X. M. Wang, B. Barletta, Characteristics of nonmethane hydrocarbons (NMHCs) in industrial, industrial-urban and industrialsuburban atmospheres of the Pearl River Delta (PRD) region of South China. J. Geophys. Res. 2006, 111, D11304.
| Characteristics of nonmethane hydrocarbons (NMHCs) in industrial, industrial-urban and industrialsuburban atmospheres of the Pearl River Delta (PRD) region of South China.Crossref | GoogleScholarGoogle Scholar |
[40] Y.-C. Li, J. Z. Yu, S. S. H. Ho, Z. B. Yuan, A. K. H. Lau, X.-F. Huang, Chemical characteristics of PM2.5 and organic aerosol source analysis during cold front episodes in Hong Kong, China. Atmos. Res. 2012, 118, 41.
| Chemical characteristics of PM2.5 and organic aerosol source analysis during cold front episodes in Hong Kong, China.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XhsVarsbvE&md5=6d958c052d781eafd7aa8176e02cf388CAS |
[41] E. C. H. Wan, J. Z. Yu, Analysis of sugars and sugar polyols in atmospheric aerosols by chloride attachment in liquid chromatography/negative ion electrospray mass spectrometry. Environ. Sci. Technol. 2007, 41, 2459.
| Analysis of sugars and sugar polyols in atmospheric aerosols by chloride attachment in liquid chromatography/negative ion electrospray mass spectrometry.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXisVSitrY%3D&md5=51dd3ad6a6a3e28b1efb831aa48f6deeCAS |
[42] B. R. T. Simoneit, V. O. Elias, M. Kobayashi, K. Kwamura, I. Rushdi, P. M. Medeiros, W. F. Rogge, B. M. Didyk, Sugars-dominant water-soluble organic compounds in soils and characterization as tracers in atmospheric particulate matter. Environ. Sci. Technol. 2004, 38, 5939.
| Sugars-dominant water-soluble organic compounds in soils and characterization as tracers in atmospheric particulate matter.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXotlamur4%3D&md5=9f0d94b6f983f1d3e3d659af9ff1d145CAS |
[43] Hong Kong air pollutants emission inventory 2006 (Hong Kong Environmental Protection Department, HKEPD). Available at http://www.epd.gov.hk/epd/tc_chi/environmentinhk/air/data/files/2006EI.xls [Verified 25 September 2013].
[44] K. Kawamura, K. Ikushima, Seasonal changes in the distribution of dicarboxylic acids in the urban atmosphere. Environ. Sci. Technol. 1993, 27, 2227.
| Seasonal changes in the distribution of dicarboxylic acids in the urban atmosphere.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3sXlsVGnt78%3D&md5=5abffe4312c91a2addf5ccf954cc6206CAS |
[45] S. Gao, K. Melita, N. L. Ng, J. Surratt, V. Varutbangkul, R. Bahreini, R. C. Flagan, J. H. Seinfeld, Low-molecular-weight and oligomeric components in secondary organic aerosol from the ozonolysis of cycloalkenes and α-pinene. J. Phys. Chem. A 2004, 108, 10147.
| Low-molecular-weight and oligomeric components in secondary organic aerosol from the ozonolysis of cycloalkenes and α-pinene.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXoslCqsrk%3D&md5=6e3165fba40d42afaf2326a569e9eb00CAS |
[46] K. Sato, S. Hatakeyama, T. Imamura, Secondary organic aerosol formation during the photooxidation of toluene: NOx dependence of chemical composition. J. Phys. Chem. A 2007, 111, 9796.
| Secondary organic aerosol formation during the photooxidation of toluene: NOx dependence of chemical composition.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXpvVyns78%3D&md5=a37d57df789b9f62173f3ff70ff80de9CAS | 17803284PubMed |
[47] U. Baltensperger, M. Kalberer, J. Dommen, D. Paulsen, M. R. Alfarra, H. Coe, R. Fisseha, A. Gascho, M. Gysel, S. Nyeki, M. Sax, M. Steinbacher, A. S. H. Prevot, S. Sjogren, E. Weingartner, R. Zenobi, Secondary organic aerosols from anthropogenic and biogenic precursors. Faraday Discuss. 2005, 130, 265.
| Secondary organic aerosols from anthropogenic and biogenic precursors.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXhtVGhtrnE&md5=30c210729724ce819ceae1e794424c48CAS | 16161788PubMed |
[48] A. G. Carlton, B. J. Turpin, K. E. Altieri, S. Seitzinger, A. Reff, H.-J. Lim, B. Ervens, Atmospheric oxalic acid and SOA production from glyoxal: results of aqueous photooxidation experiments. Atmos. Environ. 2007, 41, 7588.
| Atmospheric oxalic acid and SOA production from glyoxal: results of aqueous photooxidation experiments.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXht1yis7vJ&md5=3f93353ef136482c3558eac9b47e7e72CAS |
[49] K. E. Altieri, S. P. Seitzinger, A. G. Carlton, B. J. Turpin, G. C. Klein, A. G. Marshall, Oligomers formed through in-cloud methylglyoxal reactions: chemical composition, properties, and mechanisms investigated by ultra-high resolution FT-ICR mass spectrometry. Atmos. Environ. 2008, 42, 1476.
| Oligomers formed through in-cloud methylglyoxal reactions: chemical composition, properties, and mechanisms investigated by ultra-high resolution FT-ICR mass spectrometry.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXhvFymurs%3D&md5=5b1118b0413741d5171c978fe772e3a3CAS |
[50] M. J. Perri, S. Seitzinger, B. J. Turpin, Secondary organic aerosol production from aqueous photooxidation of glycolaldehyde: laboratory experiments. Atmos. Environ. 2009, 43, 1487.
| Secondary organic aerosol production from aqueous photooxidation of glycolaldehyde: laboratory experiments.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXhsFemtLo%3D&md5=57222d3d34ec18f71120daada32ba2b8CAS |
[51] B. Ervens, G. Feingold, G. J. Frost, S. M. Kreidenweis, A modeling study of dicarboxylic acids: 1. Chemical pathways and speciated organic mass production. J. Geophys. Res. 2004, 109, D15205.
| A modeling study of dicarboxylic acids: 1. Chemical pathways and speciated organic mass production.Crossref | GoogleScholarGoogle Scholar |
[52] P. C. Chin, Climate and weather, in A Geography of Hong Kong (Eds T. N. Chiu, C. L. So) 1986, pp. 69–85 (Oxford University Press: New York).
