Exploring the inorganic and organic nitrate aerosol formation regimes at a suburban site on the North China Plain

The Science of The Total Environment, Год журнала: 2021, Номер 768, С. 144538 - 144538

Опубликована: Янв. 7, 2021

Язык: Английский

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Important contribution of N2O5 hydrolysis to the daytime nitrate in Xi'an, China during haze periods: Isotopic analysis and WRF-Chem model simulation

Environmental Pollution, Год журнала: 2021, Номер 288, С. 117712 - 117712

Опубликована: Июль 5, 2021

Язык: Английский

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Characterizing nitrate radical budget trends in Beijing during 2013–2019

The Science of The Total Environment, Год журнала: 2021, Номер 795, С. 148869 - 148869

Опубликована: Июль 7, 2021

Язык: Английский

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Elevated Formation of Particulate Nitrate From N₂O₅ Hydrolysis in the Yangtze River Delta Region From 2011 to 2019

Geophysical Research Letters, Год журнала: 2022, Номер 49(9)

Опубликована: Апрель 21, 2022

Abstract Aerosol nitrate has become the most abundant compound during aerosol pollution in eastern China. The Chinese government implemented a stringent policy 2013–2017 to tackle pollution. However, response of nitrogen oxides (NO x ) reduction is unclear owing limitation long‐term measurement. Here, we performed 9‐year continuous measurement compositions Shanghai and confirmed decrease species except nitrate. contribution fine particulate matter (PM 2.5 increased significantly, reaching up 35% episodes after 2017. This contrast evident NO emissions. We found that elevated dinitrogen pentoxide (N 2 O 5 hydrolysis responsible for observed trend. Increased ozone decreased dioxide (NO) facilitated formation N , proportion promoted uptake eventually enhanced conversion efficiency Our results highlight importance synergic control

Язык: Английский

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A diurnal story of Δ17O($$\rm{NO}_{3}^{-}$$) in urban Nanjing and its implication for nitrate aerosol formation

npj Climate and Atmospheric Science, Год журнала: 2022, Номер 5(1)

Опубликована: Июнь 21, 2022

Abstract Inorganic nitrate production is critical in atmospheric chemistry that reflects the oxidation capacity and acidity of atmosphere. Here we use oxygen anomaly (Δ 17 O( $$\rm{NO}_{3}^{-}$$ NO3− )) high-time-resolved (3 h) aerosols to explore chemical mechanisms evolution fine particles during winter Nanjing, a megacity China. The continuous Δ ) observation suggested dominance nocturnal (NO 3 + HC/H 2 O N 5 H O/Cl − formation wintertime. Significant diurnal variations pathways were found. contribution increased at night peaked (72%) midnight. Particularly, became more important for process air pollution aggravation. In contrast, daytime OH/H O) with sunrise showed highest fraction (48%) around noon. hydrolysis on particle surfaces played an role haze days. addition, reaction NO OH radicals was found dominate after reset by precipitation events. These results suggest importance observations exploring dynamic reactive nitrogen chemistry.

Язык: Английский

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Formation mechanism and control strategy for particulate nitrate in China

Journal of Environmental Sciences, Год журнала: 2022, Номер 123, С. 476 - 486

Опубликована: Сен. 26, 2022

Язык: Английский

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Seasonal modeling analysis of nitrate formation pathways in Yangtze River Delta region, China

Atmospheric chemistry and physics, Год журнала: 2022, Номер 22(18), С. 12629 - 12646

Опубликована: Сен. 28, 2022

Abstract. Nitrate (NO3−) has been the dominant and least reduced chemical component of fine particulate matter (PM2.5) since stringent emission controls implemented in China 2013. The formation pathways NO3− vary seasonally differ substantially daytime vs. nighttime. They are affected by precursor emissions, atmospheric oxidation capacity, meteorological conditions. Understanding provides insights for design effective control strategies to mitigate pollution. In this study, Community Multiscale Air Quality (CMAQ) model was applied investigate impact regional transport, predominant physical processes, different total nitrate (TNO3, i.e., HNO3+ NO3−) production Yangtze River Delta (YRD) region during four seasons 2017. NO3-/PM2.5 NO3-/TNO3 highest winter, reaching 21 % 94 %, respectively. adjusted gas ratio (adjGR = ([NH3]+ [NO3−])/([HNO3]+ [NO3−])) YRD is generally greater than 2 across most areas YRD, indicating that mostly NH3-rich regime limited HNO3 formation. Local emissions transportation contribute concentrations throughout 50 %–62 38 %–50 majority transport contributed indirect (i.e., formed transported precursors reacting with local precursors). Aerosol (AERO, including condensation, coagulation, new particle formation, aerosol growth) processes source summer, dominated AERO (TRAN, sum horizontal vertical transport) processes. OH + NO2 pathway contributes 60 %–83 TNO3 production, N2O5 heterogeneous (HET N2O5) 10 %–36 region. HET contribution becomes more important cold warm seasons. Within planetary boundary layer Shanghai, day (98 %) summer spring night (61 winter. contributions dominate day, while dominates at night.

Язык: Английский

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Characteristics of aerosol chemistry and acidity in Shanghai after PM2.5 satisfied national guideline: Insight into future emission control

The Science of The Total Environment, Год журнала: 2022, Номер 827, С. 154319 - 154319

Опубликована: Март 4, 2022

Язык: Английский

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Secondary Formation of Submicron and Supermicron Organic and Inorganic Aerosols in a Highly Polluted Urban Area

Journal of Geophysical Research Atmospheres, Год журнала: 2023, Номер 128(4)

Опубликована: Фев. 16, 2023

Abstract Different adverse health effects of submicron (PM 1 ) and fine particles 2.5 may be attributed to their chemical differences, requiring a better understanding size‐resolved composition. Herein, extensive online measurements were conducted across seasons in Beijing by two aerosol mass spectrometers, one which alternately sampled PM . Source apportionment organic (OA) indicated that traffic‐ cooking‐related OA together accounted for ∼20%−30% the , showing insignificant seasonal variations. Coal‐combustion biomass‐burning‐related had minor contributions. The secondary (SOA) factors 59%−73% distributions particulate components varied greatly seasons. Secondary formation played key role particle size growth during cold During severe hazes with high liquid water content (ALWC), supermicron fraction (MF 1−2.5 reached ∼40%−50% while those primary remained at ∼20%. Heterogeneous uptake, aqueous processing, dissolution likely all contributed enhanced concentration components, former perhaps more important. increase MF increasing ALWC spring was less than winter, possibly due shorter duration stagnant conditions limiting formation. Early autumn showed higher values changes as varied, plausibly explained intensive new hindering persistent growth. Our results highlight importance heterogeneous uptake processing distributing SOA mode polluted areas.

Язык: Английский

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Elucidate the formation mechanism of particulate nitrate based on direct radical observations in the Yangtze River Delta summer 2019

Atmospheric chemistry and physics, Год журнала: 2023, Номер 23(4), С. 2379 - 2391

Опубликована: Фев. 21, 2023

Abstract. Particulate nitrate (NO3-) is one of the dominant components fine particles in China, especially during pollution episodes, and has a significant impact on human health, air quality, climate. Here comprehensive field campaign that focuses atmospheric oxidation capacity aerosol formation their effects Yangtze River Delta (YRD) was conducted from May to June 2019 at regional site Changzhou, Jiangsu Province China. The concentrations NO3-, OH radicals, N2O5, NO2, O3, relevant parameters were measured simultaneously. We showed high NO3- mass concentration with 10.6 ± 8.9 µg m−3 average, which accounted for 38.3 % total water-soluble particulate 32.0 PM2.5, followed by proportion sulfate, ammonium, chloride 26.0 %, 18.0 2.0 respectively. This result confirmed heavy eastern China happened not only winter, but also summer. study's ratio (NOR) emphasized solid fast YRD. It found + NO2 daytime dominated clean days, while N2O5 hydrolysis vastly enhanced became comparable polluted days (67.2 30.2 respectively). updated observed-constraint Empirical Kinetic Modeling Approach (EKMA) used assess kinetic controlling factors both local O3 productions, indicated O3-targeted scheme (VOCs : NOx = 2:1) adequate mitigating coordinately summertime this region. Our results promote understanding mechanisms mitigation based observation model simulation call more attention summertime.

Язык: Английский

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