Ambient volatile organic compounds in tropical environments: Potential sources, composition and impacts – A review

Chemosphere, Год журнала: 2021, Номер 285, С. 131355 - 131355

Опубликована: Июнь 30, 2021

Язык: Английский

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Interfacial Molecular Fractionation on Ferrihydrite Reduces the Photochemical Reactivity of Dissolved Organic Matter

Environmental Science & Technology, Год журнала: 2021, Номер 55(3), С. 1769 - 1778

Опубликована: Янв. 25, 2021

The selective sorption of dissolved organic matter (DOM) on minerals is a widespread geochemical process in the natural environment. Recent studies have explored influence this molecular fractionation DOM at water–mineral interfaces. However, it remains unclear how affects photochemistry DOM. Here, we demonstrate that adsorptive ferrihydrite greatly reduces its photoproduction reactive oxygen species (ROS) including 1O2, O2•–, and •OH normalized to carbon (ROSOC). ROSOC for were positively correlated with abundances polyphenols oxygenated polycyclic aromatics, which also observed using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) analysis be preferentially sequestered by ferrihydrite. molecules remained solution after adsorption displayed low levels ROSOC. induced therefore influenced components significantly reduced photoreactive fractions waters. These results are very important promoting our understanding effects biogeochemical features, behaviors, implications

Язык: Английский

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OCEANFILMS (Organic Compounds from Ecosystems to Aerosols: Natural Films and Interfaces via Langmuir Molecular Surfactants) sea spray organic aerosol emissions – implementation in a global climate model and impacts on clouds

Atmospheric chemistry and physics, Год журнала: 2022, Номер 22(8), С. 5223 - 5251

Опубликована: Апрель 21, 2022

Abstract. Sea spray aerosol is one of the major sources atmospheric particulate matter globally. It has increasingly been recognized that organic derived from ocean biological precursors contributes significantly to composition submicron sea and may modify impacts on clouds climate. This paper describes implementation OCEANFILMS (Organic Compounds Ecosystems Aerosols: Natural Films Interfaces via Langmuir Molecular Surfactants) parameterization for emissions in a global Earth system model, Energy Exascale System Model (E3SM). physically based model links chemistry with biogeochemistry using partitioning approach. We describe details within E3SM, compare simulated fields observations, investigate Four sensitivity cases are tested, which either strictly add or replace salt (in mass number) fully internally externally mixed salt. The simulation mixed, added organics agrees reasonably well observed seasonal cycles marine selected as default configuration E3SM. In this configuration, an additional source cloud condensation nuclei, adding up 30 cm−3 Southern Ocean boundary-layer nuclei concentrations (supersaturation = 0.1 %). addition new strengthens shortwave radiative cooling by −0.36 W m−2 annual mean more than −3.5 summertime zonal forcing Ocean, maximum about −4 around 50–60∘ S. consistent previous top-down, satellite-based empirical estimate over Ocean. Through its mechanistic approach, offers path towards improved understanding feedbacks between biology, matter,

Язык: Английский

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Fabrication of Carbon‐Based Quantum Dots via a “Bottom‐Up” Approach: Topology, Chirality, and Free Radical Processes in “Building Blocks”

Small, Год журнала: 2023, Номер 19(31)

Опубликована: Янв. 6, 2023

The discovery of carbon-based quantum dots (CQDs) has allowed opportunities for fluorescence bioimaging, tumor diagnosis and treatment, photo-/electro-catalysis. Nevertheless, in the existing reviews related to "bottom-up" approaches, attention is mainly paid applications CQDs but not formation mechanism CQDs, which derived from high complexities during synthesis CQDs. Among various synthetic methods, using small molecules as "building blocks", development a approach promoted structural design, modulation photoluminescence properties, control interfacial properties On other hand, many works have demonstrated blocks"-dependent In this review, one most important variables, relationships among intrinsic blocks" are summarized. topology, chirality, free radical process selected descriptors blocks". This review focuses on induction summary recent research results process. Moreover, several empirical rules pertaining thereto also proposed.

Язык: Английский

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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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Production of oxygenated volatile organic compounds from the ozonolysis of coastal seawater

Atmospheric chemistry and physics, Год журнала: 2024, Номер 24(6), С. 3729 - 3742

Опубликована: Март 26, 2024

Abstract. Dry deposition of ozone (O3) to the ocean surface and ozonolysis organics in sea microlayer (SSML) are potential sources volatile organic compounds (VOCs) marine atmosphere. We use a gas chromatography system coupled Vocus proton-transfer-reaction time-of-flight mass spectrometer determine chemical composition product yield select VOCs formed from coastal seawater collected Scripps Pier La Jolla, California. Laboratory-derived results interpreted context direct VOC vertical flux measurements made at Pier. The dominant products laboratory experiments largest non-sulfur emission fluxes measured field correspond CxHy+ CxHyOz+ ions. Gas (GC) analysis suggests that C5–C11 oxygenated VOCs, primarily aldehydes, contributors these ion signals. In laboratory, using flow reactor experiment, we 0.43–0.62. Pier, maximum 0.04–0.06. Scaling lab yields for an average O3 structure source 10.7 167 Tg C yr−1, competitive with DMS approximately 20.3 yr−1. This study reveals reactivity dissolved carbon can be significant atmosphere warrants further investigation into speciated different samples reactivities secondary aerosol (SOA) molecules marine-relevant, low NOx conditions.

Язык: Английский

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Measuring the Surface Tension of Atmospheric Particles and Relevant Mixtures to Better Understand Key Atmospheric Processes

Chemical Reviews, Год журнала: 2024, Номер 124(19), С. 10924 - 10963

Опубликована: Авг. 23, 2024

Aerosol and aqueous particles are ubiquitous in Earth's atmosphere play key roles geochemical processes such as natural chemical cycles, cloud fog formation, air pollution, visibility, climate forcing, etc. The surface tension of atmospheric can affect their size distribution, condensational growth, evaporation, exchange chemicals with the atmosphere, which, turn, important above-mentioned processes. However, because measuring this quantity is challenging, its role was dismissed for decades. Over last 15 years, field research has seen some tremendous developments rapidly evolving. This review presents state-of-the-art subject focusing on experimental approaches. It also a unique inventory adsorption isotherms over 130 mixtures organic compounds water relevance model development validation. Potential future areas seeking to better determine particles, constrain laboratory investigations, or understand various processes, discussed. We hope that appeals not only scientists but researchers from other fields, who could help identify new approaches solutions current challenges.

Язык: Английский

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Marine photochemistry of organic matter: Processes and impacts

Elsevier eBooks, Год журнала: 2024, Номер unknown, С. 507 - 585

Опубликована: Янв. 1, 2024

Язык: Английский

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Effect of cation enrichment on dipalmitoylphosphatidylcholine (DPPC) monolayers at the air-water interface

Journal of Colloid and Interface Science, Год журнала: 2016, Номер 478, С. 353 - 364

Опубликована: Июнь 12, 2016

Язык: Английский

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SO₂ Uptake on Oleic Acid: A New Formation Pathway of Organosulfur Compounds in the Atmosphere

Environmental Science & Technology Letters, Год журнала: 2016, Номер 3(2), С. 67 - 72

Опубликована: Янв. 26, 2016

Organosulfates are tracers for secondary organic aerosol (SOA) formation. We propose a new mechanism of organosulfur product formation in the atmosphere, which sulfur dioxide (SO2) reacts directly with alkenes. The experiments were conducted at gas–liquid interface coated-wall flow tube reactor. It was shown, first time, that SO2 efficiently unsaturated bond oleic acid under atmospheric conditions (without ozone), leading to C9 and C18 products. associated uptake coefficients excess 10–6, decreasing initial concentration increasing humidity. These results might explain fraction products detected particles. This work tends elucidate role organosulfates' interfacial chemistry as potentially unrecognized pathway their contribution SOA formation; however, it remains be determined how significant this is overall organosulfate abundances measured ambient aerosol.

Язык: Английский

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