Impact of biogenic secondary organic aerosol (SOA) loading on the molecular composition of wintertime PM_2.5 in urban Tianjin: an insight from Fourier transform ion cyclotron resonance mass spectrometry

Atmospheric chemistry and physics, Journal Year: 2023, Volume and Issue: 23(3), P. 2061 - 2077

Published: Feb. 9, 2023

Abstract. Biomass burning is one of the key sources urban aerosols in North China Plain, especially during winter, when impact secondary organic (SOAs) formed from biogenic volatile compounds (BVOCs) generally considered to be minor. However, little known about influence SOA loading on molecular composition wintertime aerosols. Here, we investigated water-soluble fine particulate matter (PM2.5) Tianjin by ultrahigh-resolution Fourier transform ion cyclotron resonanc mass spectrometry (FT-ICR MS). Our results show that most CHO and CHON are derived biomass which poor oxygen contain aromatic rings probably contribute light-absorbing brown carbon (BrC) chromophores. Under moderate high SOA-loading conditions, nocturnal chemistry more efficient than photooxidation generate with content. low loading, content mainly photochemistry. Secondary oxidation monoterpenes. may productive sesquiterpene-derived compounds. In contrast, number- intensity-weight S-containing groups (CHOS CHONS) increased significantly increase agrees fact a majority identified as organosulfates (OSs) nitrooxy–organosulfates (nitrooxy–OSs) BVOCs. Terpenes potential major contributors nitrooxy–organosulfates. While beneficial formation under loading. The an important factor associated degree, nitrate group chemodiversity nitrooxy-organosulfates. Furthermore, our study suggests hydrolysis nitrooxy-organosulfates possible pathway for organosulfates.

Language: Английский

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A Review on Brown Carbon Aerosol in China: From Molecular Composition to Climate Impact

Current Pollution Reports, Journal Year: 2024, Volume and Issue: 10(2), P. 326 - 343

Published: Feb. 29, 2024

Language: Английский

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Comparison of water-soluble and water-insoluble organic compositions attributing to different light absorption efficiency between residential coal and biomass burning emissions

Atmospheric chemistry and physics, Journal Year: 2024, Volume and Issue: 24(10), P. 6323 - 6337

Published: May 29, 2024

Abstract. There are growing concerns about the climate impacts of absorbing organic carbon (also known as brown carbon, BrC) in environment, yet its chemical composition and association with light absorption capabilities remain poorly understood. This study characterized water-soluble water-insoluble (WSOC WIOC) from residential solid fuel combustion at molecular level evaluated their quantitative relationship mass efficiency (MAE). The MAE values λ = 365 nm biomass burning were significantly higher than those coal (p < 0.05). Thousands peaks identified m/z range 150–800, most intense ion occurring between 200–500 for WSOC 600–800 WIOC, respectively. CHO group predominated extract emissions, while sulfur-containing compounds (SOCs) including CHOS CHONS more WIOC extract, particularly emissions. Emissions CHON positively correlated nitrogen content (r 0.936; p 0.05), explaining abundance emissions compared to biomass. SOC predominant during flaming phases, indicated by a positive correlation modified (MCE) 0.750; unique formulas aerosols lower H/C O/C regions, unsaturated van Krevelen (VK) diagram. In contained fractions condensed aromatics (32 %–59 %) only 4.3 %–9.7 % contrast, was larger aromatic compound combustion. Moreover, both 0.714; 0.05) extracts 0.929; 0.001), suggesting that these contributed variabilities across different fuels.

Language: Английский

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The Sources, Molecular Compositions, and Light Absorption Properties of Water‐Soluble Organic Carbon in Marine Aerosols From South China Sea to the Eastern Indian Ocean

Journal of Geophysical Research Atmospheres, Journal Year: 2022, Volume and Issue: 127(10)

Published: May 12, 2022

Abstract Water‐soluble organic carbon (WSOC) is a substantial component of carbonaceous aerosols in South/East Asia. However, the poorly constrained sources, molecular compositions, and light absorption properties WSOC over Asian marine regions lead to large uncertainty climate effects. Herein, we collected aerosol samples from South China Sea eastern Indian Ocean investigate WSOC. The δ 13 C Marine‐influenced (−20.6 ± 1.4‰) was higher than those Continent‐influenced (South Asia‐influenced: −24.4 1.1‰ Southeast −22.7 1.0‰, p < 0.01) regions. Additionally, combining with 5‐day back trajectories relationships C‐WSOC chemical tracers (Cl − /Na + nonsea salt K /K ), found that mostly related oceanic emissions, which more enriched saturated primary biological compounds lower oxidation level. In contrast, significantly affected by C3 biomass burning secondary formation, it has fraction aromatic highly oxidized compounds. Moreover, high level Continental‐influenced may result mass efficiency at 365 nm (MAE ) but low Ångström exponent (AAE) values. Taken together previous studies, MAE urban, rural background, correlated well AAE. response correlation coefficients AAE were highest urban regions, followed background likely associated different compound contents. Therefore, future, attention should be paid sources atmospheric processes condensed

Language: Английский

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Factors Influencing the Molecular Compositions and Distributions of Atmospheric Nitrogen‐Containing Compounds

Journal of Geophysical Research Atmospheres, Journal Year: 2022, Volume and Issue: 127(7)

Published: March 23, 2022

Abstract Atmospheric nitrogen‐containing organic compounds (NOCs) are critical components of global nitrogen deposition and light‐absorption species. The sources compositions NOCs complex remain largely unknown. Here, in 55 ambient aerosol samples collected Guangzhou, South China, were analyzed via ultrahigh‐resolution Fourier transform ion cyclotron resonance mass spectrometry negative‐ion positive‐ion electrospray ionization (ESI) modes. molecular measured ESI– ESI+ exhibited considerable differences. detected the negative mode mainly composed highly oxygenated nitrates (O/N = 6), whereas positive reduced (e.g., amides amino acids). CHN potentially corresponding to amines alkaloids showed low abundance detection Non‐metric multidimensional scaling individual compound correlation analyses that affected by anthropogenic activities meteorological parameters. For example, such as biomass burning secondary nitrogen‐chemistry processes led accumulation aromatic during winter. During summer, higher OH radical concentrations temperatures will result more prevalent or persistent aliphatic NOCs, particularly lipid‐like amines. Some variables relative humidity) have distinct effects on variation different types NOCs. More research is needed reveal influencing mechanisms. This study clarifies mechanisms which various factors influence variations. findings can guide assessment evolution deposition.

Language: Английский

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Unexpected molecular diversity of brown carbon formed by Maillard-like reactions in aqueous aerosols

Chemical Science, Journal Year: 2022, Volume and Issue: 13(28), P. 8401 - 8411

Published: Jan. 1, 2022

Atmospheric brown carbon (BrC) exerts a key impact on the global radiative balance due to its light-absorbing properties. Maillard-like reactions between carbonyl and amino compounds have been identified as an important pathway for forming secondary BrC. Although optical properties widely studied, molecular composition of BrC generated in Maillard chemistry remains unclear, resulting knowledge gap understand formation mechanism. In this study, combination spectroscopy, 1H nuclear magnetic resonance (NMR), Fourier transform ion cyclotron mass spectrometry (FT-ICR MS) was employed comprehensively characterize chemical characteristics The results indicate that both were highly related structures their precursors. Organic amine precursors consistently result enhanced capacities compared ammonium, but inconsistent effects diversity Compared (i.e., glycine, ethylamine, propylamine, ammonium), play more role determining Different from black carbon, products are mainly nitrogen-containing heterocycles. Unexpectedly, 35-64% formulae detected real atmospheric samples found simulated reaction products, implying potentially contribution organic pool. These will improve our understanding BrC, further help manage emissions aerosol

Language: Английский

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Impact of fossil and non-fossil fuel sources on the molecular compositions of water-soluble humic-like substances in PM_2.5 at a suburban site of Yangtze River Delta, China

Atmospheric chemistry and physics, Journal Year: 2023, Volume and Issue: 23(14), P. 8305 - 8324

Published: July 25, 2023

Abstract. Atmospheric humic-like substances (HULIS) affect the global radiation balance due to their strong light absorption at ultraviolet wavelength. The potential sources and molecular compositions of water-soluble HULIS a suburban site in Yangtze River Delta from 2017 2018 were discussed, based on results radiocarbon (14C) analysis combining Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) technique this study. 14C showed that averaged non-fossil-fuel source contributions 39 ± 8 % 36 6 summer winter, respectively, indicating significant fossil fuel HULIS. Van Krevelen diagrams obtained FT-ICR-MS proportions tannin-like carbohydrate-like groups higher summer, suggesting contribution biogenic secondary organic aerosols (SOAs). condensed aromatic structures winter suggested increasing anthropogenic emissions. Molecular composition CHO, CHON, CHOS, CHONS subgroups relatively intensities high O-containing macromolecular oligomers CHO compounds further stronger SOA formation summer. High-intensity phenolic flavonoids, which related biomass burning polycyclic hydrocarbon (PAH) derivatives combustion emissions, found compounds. Besides, two high-intensity containing ring (C9H6O7 C10H5O8) identified samples similar those off-road engine samples, traffic emissions one important study site. CHON mainly composed nitro or organonitrates with significantly associated addition enhanced NOx winter. However, formulas referring N-heterocyclic compounds, produced atmospheric processes involving reduced N species (e.g., ammonium). S-containing organosulfates (OSs) derived precursors, namely long-chain alkane hydrocarbon, illustrate mixed Generally, different policies need be considered for each season seasonal (i.e., sources, both seasons, additional coal winter). Measures control motor vehicles industrial Additional measures power plants should applied These findings add our understanding interaction between

Language: Английский

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The Sources and Atmospheric Processes of Strong Light‐Absorbing Components in Water Soluble Brown Carbon: Insights From a Multi‐Proxy Study of PM_2.5 in 10 Chinese Cities

Journal of Geophysical Research Atmospheres, Journal Year: 2024, Volume and Issue: 129(2)

Published: Jan. 17, 2024

Abstract Humic‐like substances (HULIS) are significant contributor to the light absorption of water‐soluble brown carbon (WSBrC), which contains certain strong light‐absorbing chemical components that not well understood, impeding assessment WSBrC's climate impact. China as hotspot regions with high loading WSBrC characterized by capacity, here, we investigated sources and atmospheric processes (δ 13 C–Δ 14 C), molecular composition (Fourier transform ion cyclotron resonance mass spectrometry), properties (UV spectrophotometry) HULIS in PM 2.5 from 10 Chinese cities. HULIS‐C was major coefficient (70.5 ± 6.6%) at 365 nm, more enriched fossil (48.0 9.0% vs. 30.3 13.9%) but depleted C C: −25.6 0.9‰ −22.4 1.0‰) relative non‐HULIS‐C. This suggests recalcitrant oxidative aging exhibit higher while non‐fossil organic is likely be oxidatively bleached into small, colorless, highly polar molecules (i.e., non‐HULIS). Aromatic HULIS, dominantly originating coal combustion (>77%). Non‐negative matrix factorization model showed aromatic have weight lower oxidation levels than biomass burning, potentially making them photo‐recalcitrant compounds. Our finding combustion‐derived BrC maybe persistent atmosphere has greater long‐term impact on derived burning an important consideration models mitigation policies.

Language: Английский

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Predictions of the Optical Properties of Brown Carbon Aerosol by Machine Learning with Typical Chromophores

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(46), P. 20588 - 20597

Published: Nov. 7, 2024

The linkages between BrC optical properties and chemical composition remain inadequately understood, with quantified chromophores explaining less than 25% of ambient aerosol light absorption. This study characterized 38 typical in aerosols collected Xi'an, absorption contributions to ranging from 1.6 ± 0.3 5.8 2.6% at 365 nm. Based on these chromophores, an interpretable machine learning model the Shapley Additive Explanation (SHAP) method were employed explore relationships composition. attained high accuracy Pearson correlation coefficients (

Language: Английский

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Organosulfur Compounds: A Non‐Negligible Component Affecting the Light Absorption of Brown Carbon During North China Haze Events

Journal of Geophysical Research Atmospheres, Journal Year: 2025, Volume and Issue: 130(1)

Published: Jan. 4, 2025

Abstract The roles of organosulfur compounds (OSCs), an important component in organic matter, brown carbon (BrC) aerosol absorption is often overlooked. Here, the molecular composition OSCs and its associations with methanol‐soluble BrC (MS‐BrC) during a haze event North China were revealed using Fourier transform ion cyclotron resonance mass spectrometry analysis. By combining aggregated boosted tree model partial least squares regression estimation, our results suggested that mainly composed potential aromatic structures, MS‐BrC was closely related to OSCs. Specifically, contribute notable 26% total number upper limit 10.4% absorption. Furthermore, we found influenced by coal combustion, desulfurization reactions showed variations Since residential combustion (an primary source OSs) major energy China, research underscores as tracers for assessing impact fossil fuel on highlights atmospheric influences (e.g., light health), which need more works uncover origins, fates, environmental effects

Language: Английский

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