New Multiphase Chemical Processes Influencing Atmospheric Aerosols, Air Quality, and Climate in the Anthropocene

Accounts of Chemical Research, Год журнала: 2020, Номер 53(10), С. 2034 - 2043

Опубликована: Сен. 14, 2020

ConspectusAtmospheric aerosols and fine particulate matter (PM2.5) are strongly affecting human health climate in the Anthropocene, that is, current era of globally pervasive rapidly increasing influence on planet Earth. Poor air quality associated with high aerosol concentrations is among leading risks worldwide, causing millions attributable excess deaths years life lost every year. Besides their impact, also influencing through interactions clouds solar radiation an estimated negative total effective radiative forcing may compensate about half positive carbon dioxide but exhibits a much larger uncertainty. Heterogeneous multiphase chemical reactions surface bulk solid, semisolid, liquid particles have been recognized to formation transformation thus environmental effects. However, atmospheric chemistry not well understood because its intrinsic complexity dealing multiple phases difficulties distinguishing effect from gas phase reactions.Recently, research received boost growing interest understanding severe haze very PM2.5 polluted megacities densely populated regions. State-of-the-art models suggest reactions, however, capturing rapid increase observed during events, suggesting gap our mechanisms formation. These events characterized by humidity, especially favoring chemistry. In this Account, we review recent advances made, as challenges future perspectives for processes involved transformation. We focus following questions: what key reaction pathways under conditions, relative importance versus gas-phase chemistry, implications development efficient reliable control strategies? particular, discuss related different regimes sulfate, nitrate, secondary organic (SOAs) synthesize new insights into water content, pH, state, nanoparticle size Overall, there evidence plays important role events. contrast photochemical which self-buffered against heavy pollution, feedback mechanism, where higher particle levels accelerate production, further increases concentration resulting series record-breaking pollution fill involve physical nanoscale regional global scales. A synthetic approach combining laboratory experiments, field measurements, instrument development, model simulations suggested roadmap advance research.

Язык: Английский

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A review of aerosol chemistry in Asia: insights from aerosol mass spectrometer measurements

Environmental Science Processes & Impacts, Год журнала: 2020, Номер 22(8), С. 1616 - 1653

Опубликована: Янв. 1, 2020

Aerosol mass spectrometer has been widely deployed in Asia for real-time characterization of aerosol chemistry, and significantly improved our understanding the sources, properties, formation processes aerosols a complex environment.

Язык: Английский

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A Review on Laboratory Studies and Field Measurements of Atmospheric Organic Aerosol Hygroscopicity and Its Parameterization Based on Oxidation Levels

Current Pollution Reports, Год журнала: 2020, Номер 6(4), С. 410 - 424

Опубликована: Окт. 6, 2020

Язык: Английский

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Measurements of higher alkanes using NO<sup>+</sup> chemical ionization in PTR-ToF-MS: important contributions of higher alkanes to secondary organic aerosols in China

Atmospheric chemistry and physics, Год журнала: 2020, Номер 20(22), С. 14123 - 14138

Опубликована: Ноя. 20, 2020

Abstract. Higher alkanes are a major class of intermediate-volatility organic compounds (IVOCs), which have been proposed to be important precursors secondary aerosols (SOA) in the atmosphere. Accurate estimation SOA from higher and their oxidation processes atmosphere is limited, partially due difficulty measurement. High-time-resolution (10 s) measurements were performed using NO+ chemical ionization proton transfer reaction time-of-flight mass spectrometry (NO+ PTR-ToF-MS) at an urban site Guangzhou Pearl River Delta (PRD) rural North China Plain (NCP). High concentrations observed both environments, with significant diurnal variations. At sites, production estimated photochemical losses yields. account for fractions formation two average contributions 7.0 % ± 8.0 9.4 9.1 NCP, comparable or even than single-ring aromatics naphthalenes. The suggests that they should explicitly included current models formation. Our work also highlights importance PTR-ToF-MS measuring quantifying

Язык: Английский

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Measurement report: Ambient volatile organic compound (VOC) pollution in urban Beijing: characteristics, sources, and implications for pollution control

Atmospheric chemistry and physics, Год журнала: 2022, Номер 22(18), С. 11931 - 11944

Опубликована: Сен. 15, 2022

Abstract. The increasing ozone (O3) pollution and high fraction of secondary organic aerosols (SOA) in fine particle mass has highlighted the importance volatile compounds (VOCs) air control. In this work, four intensive field measurements VOCs during winter 2018 (from 1 December to 17 January 2019), spring (15 April 27 May), summer (17 June 13 July), autumn (22 September November) 2019 were conducted at an urban site Beijing characterize VOC sources their contributions pollution. total mixing ratio 95 quantified (TVOC) observed study ranged from 5.5–118.7 ppbv with mean value 34.9 ppbv. Alkanes, OVOCs, halocarbons dominant chemical groups, accounting for 75 %–81 % TVOC across sampling months. molar ratios NOx indicated that O3 formation was limited by whole period. Positive matrix factorization (PMF) analysis showed diesel vehicle exhaust, gasoline industrial emissions main both O3-polluted PM2.5-polluted On basis impact, fuel evaporation particularly toluene, xylenes, trans-2-butene, acrolein, methyl methacrylate, vinyl acetate, 1-butene, 1-hexene, contributors, illustrating necessity conducting emission controls on these species alleviate Instead, exhaust as well coal biomass combustion found be contributors aerosol potential (SOAFP), ethylbenzene, styrene, top priority should given alleviation haze This provides insights government formulate effective control measures Beijing.

Язык: Английский

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Aqueous-Phase Reactions of Anthropogenic Emissions Lead to the High Chemodiversity of Atmospheric Nitrogen-Containing Compounds during the Haze Event

Environmental Science & Technology, Год журнала: 2023, Номер 57(43), С. 16500 - 16511

Опубликована: Окт. 16, 2023

Nitrogen-containing organic compounds (NOCs), a type of important reactive-nitrogen species, are abundant in aerosols haze events observed Northern China. However, due to the complex nature NOCs, sources, formation, and influencing factors still ambiguous. Here, molecular composition matters (OMs) hourly PM2.5 samples collected during event China was characterized using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). We found that CHON (formulas containing C, H, O, N atoms) dominated OM fractions showed high chemodiversity transformability. Relying on newly developed revised-workflow oxidation-hydrolyzation knowledge for compounds, 64% major aromatic (>80%) could be derived from oxidization or hydrolyzation processes. Results FT-ICR MS data analysis further aerosol liquid water (ALW)-involved aqueous-phase reactions distribution aromatic-CHON besides coal combustion, ALW-involved compound formation daytime nighttime different. Our results improve understanding composition, potential which can help advance evolution, control haze.

Язык: Английский

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Elucidating Secondary Organic Aerosol Processes through High-Resolution Aerosol Mass Spectrometry in Beijing

Advances in Atmospheric Sciences, Год журнала: 2025, Номер unknown

Опубликована: Янв. 24, 2025

Язык: Английский

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Dust-Dominated Coarse Particles as a Medium for Rapid Secondary Organic and Inorganic Aerosol Formation in Highly Polluted Air

Environmental Science & Technology, Год журнала: 2020, Номер 54(24), С. 15710 - 15721

Опубликована: Ноя. 25, 2020

Secondary aerosol (SA) frequently drives severe haze formation on the North China Plain. However, previous studies mostly focused submicron SA formation, thus our understanding of supermicron particles remains poor. In this study, PM2.5 chemical composition and PM10 number size distribution measurements revealed that occurred in very distinct ranges. particular, dust-dominated was surprisingly high increased with relative humidity (RH). formed aerosols reached comparable levels during evolutionary stages episodes. These results suggested dust served as a medium for rapid secondary organic inorganic under favorable photochemical RH conditions highly polluted environment. Further analysis indicated pathways differed among Overall, study highlights importance non-dust storm periods urgent need to perform size-resolved physical property future investigations are extended coarse mode because large amount thereon might have significant impacts ice nucleation, radiative forcing, human health.

Язык: Английский

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Precursors and Pathways Leading to Enhanced Secondary Organic Aerosol Formation during Severe Haze Episodes

Environmental Science & Technology, Год журнала: 2021, Номер 55(23), С. 15680 - 15693

Опубликована: Ноя. 13, 2021

Molecular analyses help to investigate the key precursors and chemical processes of secondary organic aerosol (SOA) formation. We obtained sources molecular compositions in PM2.5 winter Beijing by online offline mass spectrometer measurements. Photochemical aqueous processing were both involved producing SOA during haze events. Aromatics, isoprene, long-chain alkanes or alkenes, carbonyls such as glyoxal methylglyoxal all important precursors. The enhanced formation severe event was predominantly contributed that promoted elevated amounts water for which multifunctional nitrates most followed compounds having four oxygen atoms their formulae. latter included dicarboxylic acids various oxidation products from isoprene aromatics well oligomers uptake. Nitrated phenols, organosulfates, methanesulfonic acid also but contributions minor. Our results highlight importance reducing nitrogen oxides nitrate future control. Additionally, highly oxygenated molecules with a low degree unsaturation polluted urban environments requires further research.

Язык: Английский

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The formation and evolution of secondary organic aerosol during summer in Xi'an: Aqueous phase processing in fog-rain days

The Science of The Total Environment, Год журнала: 2020, Номер 756, С. 144077 - 144077

Опубликована: Ноя. 26, 2020

Язык: Английский

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