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Wang, Yuchen; Cocker, David R.; Griffin, Robert J.; Flagan, Richard C.; Seinfeld, John H.

doi:10.1023/a:1006254930583

Cited by 543 publications

(372 citation statements)

References 67 publications

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“…Figure 6a shows the ion trap mass spectrum of a SOA sample from R-pinene ozonolysis with preexisting MgSO 4 seed particles. The low-MW species with m/z 171, 185, and 199 correspond to norpinic acid, cis-pinic acid, and OH-pinonic acid, which have previously been identified as major SOA components 16,18 and are also identified by the LC-MS method in this work. Again, higher-MW species, such as those with m/z of 329, 343, 357, 371, and 385, are also present in this SOA.…”

Section: 21supporting

confidence: 58%

Low-Molecular-Weight and Oligomeric Components in Secondary Organic Aerosol from the Ozonolysis of Cycloalkenes and α-Pinene

et al. 2004

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The composition of secondary organic aerosol (SOA) from the ozonolysis of C 5 -C 8 cycloalkenes and R-pinene, as well as the effects of hydrocarbon precursor structure and particle-phase acidity on SOA formation, have been investigated by a series of controlled laboratory chamber experiments. A liquid chromatography-mass spectrometer and an ion trap mass spectrometer are used concurrently to identify and to quantify SOA components with molecular weights up to 1600 Da. Diacids, carbonyl-containing acids, diacid alkyl esters, and hydroxy diacids are the four major classes of low-molecular-weight (MW < 250 Da) components in the SOA; together they comprise 42-83% of the total SOA mass, assuming an aerosol density of 1.4 g/cm 3 . In addition, oligomers (MW > 250 Da) are found to be present in all SOA. Using surrogate standards, it is estimated that the mass fraction of oligomers in the total SOA is at least 10% for the cycloalkene systems (with six or more carbons) and well over 50% for the R-pinene system. Higher seed particle acidity is found to lead to more rapid oligomer formation and, ultimately, to higher SOA yields. Because oligomers are observed to form even in the absence of seed particles, organic acids produced from hydrocarbon oxidation itself may readily promote acid catalysis and oligomer formation. The distinct effects of carbon numbers, substituent groups, and isomeric structures of the precursor hydrocarbons on the composition and yield of SOA formed are also discussed.

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Section: 21supporting

confidence: 58%

Low-Molecular-Weight and Oligomeric Components in Secondary Organic Aerosol from the Ozonolysis of Cycloalkenes and α-Pinene

et al. 2004

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“…Although these techniques could provide the molecular formula of the compounds, the molecular structures are unknown. In order to derive further information, comparison to previous publications was performed for the major oxidation products from (a) the β-pinene ozonolysis (Chen and Griffin, 2005;Hohaus et al, 2015;Jenkin, 2004;Yu et al, 1999), (b) limonene ozonolysis and NO 3 oxidation (Chen and Griffin, 2005;Jaoui et al, 2006;Kundu et al, 2012;Leungsakul et al, 2005a, b) and (c) tree emissions ozonolysis, with α-pinene and 3 -carene being the major reactants (Chen and Griffin, 2005;Praplan et al, 2015;Yu et al, 1999). Results showed that all techniques were able to detect most of the expected molecules.…”

Section: Compound Detection Comparison and Tracer Attributionmentioning

confidence: 99%

Comparison of three aerosol chemical characterization techniques utilizing PTR-ToF-MS: a study on freshly formed and aged biogenic SOA

Gkatzelis¹,

Tillmann²,

Hohaus³

et al. 2018

Atmos. Meas. Tech.

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Abstract. An intercomparison of different aerosol chemical characterization techniques has been performed as part of a chamber study of biogenic secondary organic aerosol (BSOA) formation and aging at the atmosphere simulation chamber SAPHIR (Simulation of Atmospheric PHotochemistry In a large Reaction chamber). Three different aerosol sampling techniques -the aerosol collection module (ACM), the chemical analysis of aerosol online (CHARON) and the collection thermal-desorption unit (TD) were connected to proton transfer reaction time-of-flight mass spectrometers (PTR-ToF-MSs) to provide chemical characterization of the SOA. The techniques were compared among each other and to results from an aerosol mass spectrometer (AMS) and a scanning mobility particle sizer (SMPS). The experiments investigated SOA formation from the ozonolysis of β-pinene, limonene, a β-pinene-limonene mix and real plant emissions from Pinus sylvestris L. (Scots pine). The SOA was subsequently aged by photo-oxidation, except for limonene SOA, which was aged by NO 3 oxidation. Despite significant differences in the aerosol collection and desorption methods of the PTR-based techniques, the determined chemical composition, i.e. the same major contributing signals, was found by all instruments for the different chemical systems studied. These signals could be attributed to known products expected from the oxidation of the examined monoterpenes. The sampling and desorption method of ACM and TD provided additional information on the volatility of individual compounds and showed relatively good agreement.Averaged over all experiments, the total aerosol mass recovery compared to an SMPS varied within 80 ± 10, 51 ± 5 and 27 ± 3 % for CHARON, ACM and TD, respectively. Comparison to the oxygen-to-carbon ratios (O : C) obtained by AMS showed that all PTR-based techniques observed lower O : C ratios, indicating a loss of molecular oxygen either during aerosol sampling or detection. The differences in total mass recovery and O : C between the three instruments resulted predominantly from differences in the field strength (E/N) in the drift tube reaction ionization chambers of the PTR-ToF-MS instruments and from dissimilarities in the collection/desorption of aerosols. Laboratory case studies showed that PTR-ToF-MS E/N conditions influenced fragmentation which resulted in water and further neutral fragment losses of the detected molecules. Since ACM and TD were operated in higher E/N than CHARON, this resulted in higher fragmentation, thus affecting primarily the detected oxygen and carbon content and therefore also the mass recovery. Overall, these techniques have been shown to provide

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“…Considerable variability is observed in the yield of SOA generated by BVOC oxidation (e.g. Yu et al, 1999a;Kroll et al, 2006;Shilling et al, 2009). …”

Section: Gas-phase Emissions and Chemistrymentioning

confidence: 99%

The direct and indirect radiative effects of biogenic secondary organic aerosol

et al. 2014

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Abstract. We use a global aerosol microphysics model in combination with an offline radiative transfer model to quantify the radiative effect of biogenic secondary organic aerosol (SOA) in the present-day atmosphere. Through its role in particle growth and ageing, the presence of biogenic SOA increases the global annual mean concentration of cloud condensation nuclei (CCN; at 0.2 % supersaturation) by 3.6-21.1 %, depending upon the yield of SOA production from biogenic volatile organic compounds (BVOCs), and the nature and treatment of concurrent primary carbonaceous emissions. This increase in CCN causes a rise in global annual mean cloud droplet number concentration (CDNC) of 1.9-5.2 %, and a global mean first aerosol indirect effect (AIE) of between +0.01 W m −2 and −0.12 W m −2 . The radiative impact of biogenic SOA is far greater when biogenic oxidation products also contribute to the very early stages of new particle formation; using two organically mediated mechanisms for new particle formation, we simulate global annual mean first AIEs of −0.22 W m −2 and −0.77 W m −2 . The inclusion of biogenic SOA substantially improves the simulated seasonal cycle in the concentration of CCN-sized particles observed at three forested sites. The best correlation is found when the organically mediated nucleation mechanisms are applied, suggesting that the first AIE of biogenic SOA could be as large as −0.77 W m −2 . The radiative impact of SOA is sensitive to the presence of anthropogenic emissions. Lower background aerosol concentrations simulated with anthropogenic emissions from 1750 give rise to a greater fractional CCN increase and a more substantial first AIE from biogenic SOA. Consequently, the anthropogenic indirect radiative forcing between 1750 and the present day is sensitive to assumptions about the amount and role of biogenic SOA. We also calculate an annual global mean direct radiative effect of between −0.08 W m −2 and −0.78 W m −2 in the present day, with uncertainty in the amount of SOA produced from the oxidation of BVOCs accounting for most of this range.

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Untitled

Cited by 543 publications

References 67 publications

Low-Molecular-Weight and Oligomeric Components in Secondary Organic Aerosol from the Ozonolysis of Cycloalkenes and α-Pinene

Low-Molecular-Weight and Oligomeric Components in Secondary Organic Aerosol from the Ozonolysis of Cycloalkenes and α-Pinene

Comparison of three aerosol chemical characterization techniques utilizing PTR-ToF-MS: a study on freshly formed and aged biogenic SOA

The direct and indirect radiative effects of biogenic secondary organic aerosol

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