Significantly Accelerated Photosensitized Formation of Atmospheric Sulfate at the Air–Water Interface of Microdroplets

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(10), С. 6580 - 6590

Опубликована: Март 1, 2024

The multiphase oxidation of sulfur dioxide (SO2) to form sulfate is a complex and important process in the atmosphere. While conventional photosensitized reaction mainly explored bulk medium reported be one drivers trigger atmospheric production, how this scheme functionalizes at air–water interface (AWI) aerosol remains an open question. Herein, employing advanced size-controllable microdroplet-printing device, surface-enhanced Raman scattering (SERS) analysis, nanosecond transient adsorption spectrometer, molecular level theoretical calculations, we revealed previously overlooked interfacial role SO2 humic-like substance (HULIS) aerosol, where 3–4 orders magnitude increase formation rate was speculated cloud relevant-sized particles relative bulk-phase medium. rapid battery reactive oxygen species (ROS) comes from accelerated electron transfer AWI, excited triplet state HULIS (3HULIS*) incomplete solvent cage can readily capture electrons HSO3– way that more efficient than fully blocked by water molecules. This phenomenon could explained significantly reduced desolvation energy barrier required for reagents residing AWI region with shell.

Язык: Английский

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Optical properties, chemical functional group, and oxidative activity of different polarity levels of water-soluble organic matter in PM2.5 from biomass and coal combustion in rural areas in Northwest China

Atmospheric Environment, Год журнала: 2022, Номер 283, С. 119179 - 119179

Опубликована: Май 17, 2022

Язык: Английский

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Optical properties, molecular characterizations, and oxidative potentials of different polarity levels of water-soluble organic matters in winter PM2.5 in six China's megacities

The Science of The Total Environment, Год журнала: 2022, Номер 853, С. 158600 - 158600

Опубликована: Сен. 8, 2022

Язык: Английский

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Technical note: Chemical composition and source identification of fluorescent components in atmospheric water-soluble brown carbon by excitation–emission matrix spectroscopy with parallel factor analysis – potential limitations and applications

Atmospheric chemistry and physics, Год журнала: 2023, Номер 23(4), С. 2613 - 2625

Опубликована: Фев. 24, 2023

Abstract. Three-dimensional excitation–emission matrix (EEM) fluorescence spectroscopy is an important method for the identification of occurrence, chemical composition, and source atmospheric chromophores. However, current knowledge on interpretation fluorescent components mainly based aquatic dissolved organic matter might not be applicable to samples. Therefore, this study comprehensively investigated EEM data different types strong light-absorbing compounds, water-soluble (WSOM) in aerosol samples (combustion ambient aerosols), soil dust, purified fulvic humic acids supplemented by parallel factor (PARAFAC) modeling. The results demonstrated that compounds with high aromaticity electron-donating groups generally present spectra at longer emission wavelengths, whereas substituted electron-withdrawing have relatively weaker intensity. In particular, aromatic containing nitro (i.e., nitrophenols), which show absorption are major component brown carbon, exhibited no significant fluorescence. EEM–PARAFAC identified three C1, C2, C3) WSOM. Although EEM–PARAFAC-derived C1 (Ex/Em = 235, 270/330 nm) WSOM considered protein-like groups, our findings suggested it composed acids, phenolic their derivatives, only traces amino acids. C2 associated reaction biomass burning and/or biogenic molecules, a lower degree oxidation, more abundant Guangzhou (56 %–69 %). C3, contrast, attributed highly oxygenated molecules derived from aging processes has higher contribution Chuzhou (23 These provide new insights into analysis properties sources fluorophores using method.

Язык: Английский

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Oxidized and Unsaturated: Key Organic Aerosol Traits Associated with Cellular Reactive Oxygen Species Production in the Southeastern United States

Environmental Science & Technology, Год журнала: 2023, Номер 57(38), С. 14150 - 14161

Опубликована: Сен. 12, 2023

Exposure to ambient fine particulate matter (PM2.5) is associated with millions of premature deaths annually. Oxidative stress through overproduction reactive oxygen species (ROS) a possible mechanism for PM2.5-induced health effects. Organic aerosol (OA) dominant component PM2.5 worldwide, yet its role in toxicity poorly understood due chemical complexity. Here, integrated cellular ROS measurements and detailed multi-instrument characterization PM urban southeastern United States, we show that oxygenated OA (OOA), especially more-oxidized OOA, the main type production. We further reveal highly unsaturated containing carbon–oxygen double bonds aromatic rings OOA are major contributors These results highlight key features driving toxicity. As ubiquitous abundant atmosphere, this emphasizes need understand sources processing when formulating effective strategies mitigate impacts.

Язык: Английский

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Insight into the Role of NH₃/NH₄⁺ and NO_x/NO₃^– in the Formation of Nitrogen-Containing Brown Carbon in Chinese Megacities

Environmental Science & Technology, Год журнала: 2024, Номер unknown

Опубликована: Фев. 23, 2024

Particulate brown carbon (BrC) plays a crucial role in the global radiative balance due to its ability absorb light. However, effect of molecular formation on light absorption properties BrC remains poorly understood. In this study, atmospheric samples collected from six Chinese megacities winter and summer were characterized through ultrahigh-performance liquid chromatography coupled with Orbitrap mass spectrometry (UHPLC-Orbitrap MS) measurements. The average values coefficient at wavelength 365 nm (babs365) approximately 4.0 times higher than those summer. Nitrogen-containing organic molecules (CHNO) identified as critical components light-absorbing substances both seasons, underscoring importance N-addition BrC. These nitrogen-containing chromophores more closely related nitro-containing compounds originating biomass burning nitrogen oxides (NOx)/nitrate (NO3–) reactions winter. summer, they reduced N-containing formed ammonia (NH3)/ammonium (NH4+) reactions. NH3/NH4+-mediated contributed secondary winter, particularly southern cities. Compared O/Cw, lower molecule conjugation indicator (double bond equivalent, DBE), babs365 suggest possible bleaching mechanism during oxidation process. findings strengthen connection between composition BrC, providing insights into mechanisms across northern cities different seasons.

Язык: Английский

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Size distribution, community composition, and influencing factors of bioaerosols on haze and non-haze days in a megacity in Northwest China

The Science of The Total Environment, Год журнала: 2022, Номер 838, С. 155969 - 155969

Опубликована: Май 16, 2022

Язык: Английский

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Oxidative potential of atmospheric brown carbon in six Chinese megacities: Seasonal variation and source apportionment

Atmospheric Environment, Год журнала: 2023, Номер 309, С. 119909 - 119909

Опубликована: Июнь 15, 2023

Язык: Английский

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

Current Pollution Reports, Год журнала: 2024, Номер 10(2), С. 326 - 343

Опубликована: Фев. 29, 2024

Язык: Английский

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Molecular compositions and optical properties of water-soluble brown carbon during the autumn and winter in Guangzhou, China

Atmospheric Environment, Год журнала: 2022, Номер 296, С. 119573 - 119573

Опубликована: Дек. 30, 2022

Язык: Английский

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