The role of naphthalene and its derivatives in the formation of secondary organic aerosol in the Yangtze River Delta region, China

Atmospheric chemistry and physics, Год журнала: 2024, Номер 24(12), С. 7467 - 7479

Опубликована: Июль 1, 2024

Abstract. Naphthalene (Nap) and its derivatives, including 1-methylnaphthalene (1-MN) 2-methylnaphthalene (2-MN), serve as prominent intermediate volatile organic compounds (IVOCs) contribute to the formation of secondary aerosol (SOA). In this study, Community Multiscale Air Quality (CMAQ) model coupled with detailed emissions reactions these was utilized examine their roles in SOA other pollutants Yangtze River Delta (YRD) region during summer. Significant underestimations Nap MN concentrations (by 79 % 85 %) were observed at Taizhou site based on results using default emissions. Constrained by observations, anthropogenic entire multiplied 5 7, respectively, better capture evolution pollutants. The average concentration reached 25 ppt (parts per trillion) YRD, contributing 4.1 8.1 (up 12.6 total aromatic aromatic-derived carbon (SOC), respectively. 1-MN 2-MN relatively low, averaging 2 ppt, Together, they accounted for only 2.4 SOC. impacts oxidation ozone radicals insignificant regional scales but not negligible when considering daily fluctuations locations high MN. This study highlights significant SOA, which may pose environmental risks result adverse health effects.

Язык: Английский

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Online measurements of cycloalkanes based on NO⁺ chemical ionization in proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS)

Atmospheric measurement techniques, Год журнала: 2022, Номер 15(23), С. 6935 - 6947

Опубликована: Дек. 2, 2022

Abstract. Cycloalkanes are important trace hydrocarbons existing in the atmosphere, and they considered a major class of intermediate volatile organic compounds (IVOCs). Laboratory experiments showed that yields secondary aerosols (SOAs) from oxidation cycloalkanes higher than acyclic alkanes with same carbon number. However, measurements atmosphere still challenging at present. In this study, we show online can be achieved using proton transfer reaction time-of-flight mass spectrometry NO+ chemical ionization (NO+ PTR-ToF-MS). Cyclic bicyclic ionized via hydride ion transfer, leading to product ions CnH2n-1+ CnH2n-3+, respectively. As isomers cycloalkanes, alkenes undergo association reactions CnH2n ⚫ (NO)+, concentrations 1-alkenes trans-2-alkenes usually significantly lower (about 25 % <5 %, respectively), as result inducing little interference cycloalkane detection atmosphere. Calibrations various similar sensitivities associated small humidity dependence. Applying method, were successfully measured an urban site southern China during chassis dynamometer study vehicular emissions. Concentrations both cyclic significant air emissions, comparable / ratios between gasoline vehicles. These results demonstrate PTR-ToF-MS provides new complementary approach for fast characterization ambient emission sources, which helpful fill gap understanding importance

Язык: Английский

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Heterogeneous Reactions of α-Pinene on Mineral Surfaces: Formation of Organonitrates and α-Pinene Oxidation Products

The Journal of Physical Chemistry A, Год журнала: 2022, Номер 126(25), С. 4068 - 4079

Опубликована: Июнь 16, 2022

Organonitrates (ON) are important components of secondary organic aerosols (SOAs). α-Pinene (C10H16), the most abundant monoterpene in troposphere, is a precursor for formation several these compounds. ON from α-pinene can be produced gas phase via photochemical processes and/or following reactions with oxidizers including hydroxyl radical and ozone. Gas-phase nitrogen oxides (NO2, NO3) N sources formation. Although gas-phase that yield fairly well understood, little known about their through heterogeneous multiphase pathways. In current study, surface on hematite (α-Fe2O3) kaolinite (SiO2Al2O3(OH)4) surfaces, common mineral dust, have been investigated. oxidizes upon adsorption kaolinite, forming pinonaldehyde, which then dimerizes surface. Furthermore, shown to react adsorbed nitrate species surfaces producing multiple other oxidation products. Additionally, products more strongly adsorb compared α-pinene. Overall, this study reveals complexity prevalent compounds such as dioxide, revealing new reaction pathways SOA mineralogy specific.

Язык: Английский

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Comparison of secondary organic aerosol generated from the oxidation of laboratory precursors by hydroxyl radicals, chlorine atoms, and bromine atoms in an oxidation flow reactor

Environmental Science Atmospheres, Год журнала: 2022, Номер 2(4), С. 687 - 701

Опубликована: Янв. 1, 2022

We characterized the chemical composition and yield of laboratory SOA generated in an oxidation flow reactor from OH Cl n -dodecane toluene, OH, Cl, Br isoprene α-pinene.

Язык: Английский

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In-situ measurement of secondary aerosol formation potential using a flow reactor: Livestock agricultural area

Atmospheric Environment, Год журнала: 2023, Номер 301, С. 119695 - 119695

Опубликована: Март 2, 2023

Язык: Английский

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