Quantifying New Sources of Ambient Organic Aerosol and Their Roles in Particle Growth Using Oxygenated Organic Molecule (OOM) Tracers

Environmental Science & Technology Letters, Journal Year: 2024, Volume and Issue: 11(9), P. 988 - 995

Published: Aug. 6, 2024

China is suffering from frequent PM2.5 episodes in the winter characterized by rapid particle growth. Organic aerosol (OA) often bottleneck of further reducing PM pollution. To devise effective control measures, sources OA must be identified and quantified first. This study expanded capability cutting-edge iodide-based chemical ionization mass spectrometry a source apportionment measuring variety oxygenated organic molecules (OOMs). A workflow was developed to find suitable tracers these OOMs. The research OAs advanced incorporating OOM with traditional nonpolar/polar tracers. OOMs-incorporated positive matrix factorization (PMF) applied two unique groups samples collected an inland megacity ocean expedition. PMF without overestimated contribution fossil fuel combustion, plastic burning, monoterpene SOA. On average, assigned 28.8% 44.1% marine samples, respectively, 4 new factors: aliphatic SOA, highly oxidized aromatic sulfur-containing nitrogen-containing one-hour resolution measurement found SOA were significantly enhanced particles during nighttime daytime growth events, respectively.

Language: Английский

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Substantial contribution of transported emissions to organic aerosol in Beijing

Nature Geoscience, Journal Year: 2024, Volume and Issue: 17(8), P. 747 - 754

Published: Aug. 1, 2024

Haze in Beijing is linked to atmospherically formed secondary organic aerosol, which has been shown be particularly harmful human health. However, the sources and formation pathways of these aerosols remain largely unknown, hindering effective pollution mitigation. Here we have quantified aerosol via direct near-molecular observations central Beijing. In winter, arises mainly from fresh solid-fuel emissions originating both combustion aqueous processes, probably involving multiphase chemistry with aromatic compounds. The most severe haze combustion, transported Beijing-Tianjing-Hebei Plain rural mountainous areas west summer, increased fraction dominated by Xi'an-Shanghai-Beijing region, while contribution biogenic remains relatively small. Overall, identify main affecting Beijing, clearly extend beyond local Our results suggest that targeting key precursor emission sectors regionally may needed effectively mitigate pollution.

Language: Английский

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Linking Precursors and Volatility of Ambient Oxygenated Organic Aerosols Using Thermal Desorption Measurement and Machine Learning

ACS ES&T Air, Journal Year: 2024, Volume and Issue: 1(10), P. 1239 - 1251

Published: Aug. 27, 2024

We conducted thermal desorption measurements and machine learning analysis to investigate the volatility precursors of ambient oxygenated organic aerosols (OOA), with a focus on link between them, in variety urban marine locations. found that OOA species measured by an iodide-based Chemical Ionization Mass Spectrometer equipped Filter Inlet for Gases AEROsol (FIGAERO-CIMS) accounted 16 ± 13% OA those locations represented mostly secondary moderate-volatility portion OA. On average, 25.1% number 26.8% mass detected FIGAERO-CIMS winter campaign at site Wuhan, megacity central China, might be attributed decomposition fragments. Our results show precursor differed systematically according location, season, pollution level. The ocean atmosphere was characterized high fractions extremely low compounds (ELVOC) aliphatic species, while inland aromatic fell primarily into (LVOCs) semivolatile (SVOCs) range. volatilities summer, days, daytime were lower than winter, clean nighttime. When PM episode developed from particle growth then period, shifted Low-Mw Median-Mw highly nonvolatile species. study this work also provides important data future closure studies SOA formation its precursors.

Language: Английский

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Dust event identification and characterization with one-year online observations in Beijing

The Science of The Total Environment, Journal Year: 2024, Volume and Issue: 956, P. 177296 - 177296

Published: Nov. 4, 2024

Language: Английский

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The semi-solid phase of atmospheric particles facilitates the formation of secondary brown carbon: possible contribution of ionic strength to Maillard-like reactions

Atmospheric Environment, Journal Year: 2024, Volume and Issue: unknown, P. 120991 - 120991

Published: Dec. 1, 2024

Language: Английский

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