Organic Peroxides in Aerosol: Key Reactive Intermediates for Multiphase Processes in the Atmosphere

Chemical Reviews, Год журнала: 2023, Номер 123(4), С. 1635 - 1679

Опубликована: Янв. 11, 2023

Organic peroxides (POs) are organic molecules with one or more peroxide (−O–O−) functional groups. POs commonly regarded as chemically labile termination products from gas-phase radical chemistry and therefore serve temporary reservoirs for oxidative radicals (HOx ROx) in the atmosphere. Owing to their ubiquity, active gas-particle partitioning behavior, reactivity, key reactive intermediates atmospheric multiphase processes determining life cycle (formation, growth, aging), climate, health impacts of aerosol. However, there remain substantial gaps origin, molecular diversity, fate due complex nature dynamic behavior. Here, we summarize current understanding on POs, a focus identification quantification, state-of-the-art analytical developments, molecular-level formation mechanisms, chemical transformation pathways, well environmental impacts. We find that interactions SO2 transition metal ions generally fast PO pathways liquid water, lifetimes estimated be minutes hours, while hydrolysis is particularly important α-substituted hydroperoxides. Meanwhile, photolysis thermolysis likely minor sinks POs. These distinctly different fates, such reaction OH radicals, which highlights need understand By summarizing advances remaining challenges investigation propose future research priorities regarding fate,

Язык: Английский

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Washable and flexible gas sensor based on UiO-66-NH2 nanofibers membrane for highly detecting SO2

Chemical Engineering Journal, Год журнала: 2021, Номер 428, С. 131720 - 131720

Опубликована: Авг. 10, 2021

Язык: Английский

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A critical review of sulfate aerosol formation mechanisms during winter polluted periods

Journal of Environmental Sciences, Год журнала: 2022, Номер 123, С. 387 - 399

Опубликована: Июль 16, 2022

Язык: Английский

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Sulfate Formation Apportionment during Winter Haze Events in North China

Environmental Science & Technology, Год журнала: 2022, Номер 56(12), С. 7771 - 7778

Опубликована: Май 24, 2022

There is a large gap between the simulated and observed sulfate concentrations during winter haze events in North China. Although multiphase formation mechanisms have been proposed, they not evaluated using chemical transport models. In this study, Weather Research Forecasting model coupled with Chemistry (WRF-Chem) was used to apportion formation. It found that Mn-catalyzed oxidation on aerosol surfaces dominant pathway, accounting for 92.3 ± 3.5% of events. Gas-phase contributed 3.1 0.5% due low OH levels. The H2O2 water accounted 4.2 3.6% formation, caused by rapid consumption H2O2. contributions O3, NO2 oxidation, transition metal ion-catalyzed reactions could be negligible owing content, pH, high ionic strength. from in-cloud were barrier provided stable stratification

Язык: Английский

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Sulfate Formation in Incense Burning Particles: A Single-Particle Mass Spectrometric Study

Environmental Science & Technology Letters, Год журнала: 2022, Номер 9(9), С. 718 - 725

Опубликована: Авг. 26, 2022

Incense burning is a common ritual in Asian communities, and it emits massive amounts of particles. These particles can undergo atmospheric aging upon exposure to sunlight other pollutants. In this work, we observed sulfate formation fresh incense SO2, using single-particle aerosol mass spectrometer (SPAMS). Analysis the positive spectra classified as K-type OC-type. both dark light experiments, SO2 uptake oxidation were found preferentially OC-type over Sulfate formation, represented by number fraction sulfate-containing (FS), under was likely due gaseous oxidants. FS increased with UV, mainly attributable photosensitization reactions. While more formed at higher relative humidity (RH) dark, independent RH. The increase photochemistry effective lower RH, where photoactive compounds concentrated generated photo-oxidants. This effect outweighed that reduced dissolution. Since contain organic photosensitizers have also been biomass particles, our findings could shed on potential trigger formation.

Язык: Английский

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Single-particle Raman spectroscopy for studying physical and chemical processes of atmospheric particles

Atmospheric chemistry and physics, Год журнала: 2022, Номер 22(5), С. 3017 - 3044

Опубликована: Март 7, 2022

Abstract. Atmospheric particles experience various physical and chemical processes change their properties during lifetime. Most studies on atmospheric particles, both in laboratory field measurements, rely analyzing an ensemble of particles. Because different mixing states individual only average can be obtained from using ensembles To better understand the fate environmental impacts investigations at a single-particle level are valuable. Among wealth analytic techniques, Raman spectroscopy provides unambiguous characterization under pressure non-destructive situ manner. This paper comprehensively reviews application such technique including particle hygroscopicity, phase transition separation, solute–water interactions, pH, multiphase reactions. Investigations enhanced bioaerosols basis also reviewed. For each application, we describe principle representative examples studies. Finally, present our views future directions development further applications studying

Язык: Английский

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Targeting Atmospheric Oxidants Can Better Reduce Sulfate Aerosol in China: H₂O₂ Aqueous Oxidation Pathway Dominates Sulfate Formation in Haze

Environmental Science & Technology, Год журнала: 2022, Номер 56(15), С. 10608 - 10618

Опубликована: Июль 5, 2022

Particulate sulfate is one of the most important components in atmosphere. The observation rapid aerosol production during haze events provoked scientific interest multiphase oxidation SO2 aqueous particles. Diverse pathways can be enhanced or suppressed under different acidity levels and high ionic strength conditions atmospheric aerosol. importance to chemistry has been verified laboratory conditions, though studies actual atmosphere are still limited. By utilizing online observations developing an improved solute strength-dependent chemical thermodynamics kinetics model (EF-T&K model, EF enhancement factor that represents effect on aqueous-phase reaction), we provided quantitative evidence H2O2 pathway was nearly 100 times dominated formation for entire years (66%) Tianjin (a northern city China). TMI (oxygen catalyzed by transition-metal ions) (14%) NO2 got second-highest contributions. Machine learning supported result more affected pathway. collaborative effects oxidants were further investigated using EF-T&K model. Our findings highlight effectiveness adopting target oxidant control as a new direction sustainable mitigation sulfate, given already low concentrations China.

Язык: Английский

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Imaging of pH distribution inside individual microdroplet by stimulated Raman microscopy

Proceedings of the National Academy of Sciences, Год журнала: 2023, Номер 120(20)

Опубликована: Май 8, 2023

Aerosol microdroplets as microreactors for many important atmospheric reactions are ubiquitous in the atmosphere. pH largely regulates chemical processes within them; however, how and species spatially distribute an microdroplet is still under intense debate. The challenge to measure distribution a tiny volume without affecting distribution. We demonstrate method based on stimulated Raman scattering microscopy visualize three-dimensional inside single of varying sizes. find that surface all more acidic, monotonic trend decreasing observed 2.9-μm aerosol from center edge, which well supported by molecular dynamics simulation. However, bigger cloud differs small This size-dependent can be related surface-to-volume ratio. work presents noncontact measurement imaging microdroplets, filling gap our understanding spatial aerosol.

Язык: Английский

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Significant formation of sulfate aerosols contributed by the heterogeneous drivers of dust surface

Atmospheric chemistry and physics, Год журнала: 2022, Номер 22(20), С. 13467 - 13493

Опубликована: Окт. 19, 2022

Abstract. The importance of dust heterogeneous oxidation in the removal atmospheric SO2 and formation sulfate aerosols is not adequately understood. In this study, Fe-, Ti-, Al-bearing components, Na+, Cl−, K+, Ca2+ surface, were discovered to be closely associated with sulfate. Regression models then developed make a reliable prediction reactivity based on particle chemical compositions. Further, recognized gas-phase, aqueous-phase, routes quantitatively assessed kinetically compared by combining laboratory work modelling study. presence 55 µg m−3 airborne dust, accounts for approximately 28.6 % secondary during nighttime, while proportion decreases 13.1 solar irradiation. On drivers (e.g. transition metal constituents, water-soluble ions) are more efficient than surface-adsorbed oxidants H2O2, NO2, O3) conversion SO2, particularly nighttime. Dust offers an opportunity explain missing source severe haze pollution events, its contribution complex environments could even higher current calculation results. Overall, surface responsible significant have profound impacts sulfur cycling.

Язык: Английский

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The shifting of secondary inorganic aerosol formation mechanisms during haze aggravation: the decisive role of aerosol liquid water

Atmospheric chemistry and physics, Год журнала: 2023, Номер 23(4), С. 2365 - 2378

Опубликована: Фев. 21, 2023

Abstract. Although many considerable efforts have been done to reveal the driving factors on haze aggravation, however, roles of aerosol liquid water (ALW) in secondary inorganic (SIA) formation were mainly focused condition content (ALWC) < 100 µg m−3. Based situ high-resolution field observations, this work studied decisive and shifting mechanisms during revealing different ALWC a broader scale (∼500 m−3) nitrate sulfate induced by aqueous chemistry ammonia-rich atmosphere. The results showed that chemical domains perturbation gas limiting generation particulate matter presented obvious shifts from HNO3-sensitive HNO3- NH3-co-sensitive regime with indicating powerful effects ammonia When 75 m−3, was preferentially triggered high utilization then accelerated nitrogen oxide oxidation clean moderate pollution stages, characterized ratio (NOR) 0.3, sulfur (SOR) 0.4, transition (NTR) 0.7 moral NO3-/SO42-=2:1. > aqueous-phase reaction SO2 NH3 ALW became prerequisite for SIA driven Henry's law atmosphere heavy serious SOR (0.5–0.9), NOR (0.3–0.5) NTR (>0.7), as well NO3-/SO42-=1:1. A positive feedback production also observed due shift partitioning variation aggravation. It implies target controlling should not simply focus NO2, but more attention be paid gaseous precursors (e.g., SO2, NH3) constitution stages.

Язык: Английский

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