New particle formation from isoprene under upper-tropospheric conditions

Nature, Journal Year: 2024, Volume and Issue: 636(8041), P. 115 - 123

Published: Dec. 4, 2024

Language: Английский

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Atmospheric aerosol spatial variability: Impacts on air quality and climate change

One Earth, Journal Year: 2025, Volume and Issue: 8(3), P. 101237 - 101237

Published: March 1, 2025

Language: Английский

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Characteristics of new particle formation events at high-altitude location of Western Himalayan Region, Tehri Garhwal, India

Atmospheric Research, Journal Year: 2025, Volume and Issue: unknown, P. 107903 - 107903

Published: Jan. 1, 2025

Language: Английский

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Geochemistry of vegetation fires using levoglucosan: a review

Environmental Chemistry Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 4, 2025

Language: Английский

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Atmospheric amines are a crucial yet missing link in Earth’s climate via airborne aerosol production

Communications Earth & Environment, Journal Year: 2025, Volume and Issue: 6(1)

Published: Feb. 10, 2025

Atmospheric amines, derivatives of ammonia, play a unique yet not fully understood role in air quality, climate and public health. Sub-5 parts per trillion Volume (pptV, <10-12 volume) mixing ratios amines facilitate the physical and/or chemical transformation aerosols atmosphere, enhancing aerosol formation growth rates, hygroscopicity, activation cloud condensation nuclei. This serves as initial step for droplet and, consequently, influences properties hydrological cycle. Ambient observations demonstrate more than thousand-fold particle rates presence compared to ammonia. Yet, challenges related detecting minute levels paucity ambient amine measurements, limited process-based understanding airborne production have resulted being underrepresented global models. Therefore, advanced techniques with extremely low detection limits highly spatially temporally resolved measurements globally diverse environments are essential. Amines, ubiquitous atmospheric compounds that emitted from range natural anthropogenic sources, key activating nuclei, under-represented models require future high-precision measurement.

Language: Английский

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Global Simulations of Phase State and Equilibration Time Scales of Secondary Organic Aerosols with GEOS-Chem

ACS Earth and Space Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 10, 2025

The phase state of secondary organic aerosols (SOA) can range from liquid through amorphous semisolid to glassy solid, which is important consider as it influences various multiphase processes including SOA formation and partitioning, chemistry, cloud activation. In this study, we simulate the glass transition temperature viscosity over globe using global chemical transport model, GEOS-Chem. simulated spatial distributions show that at surface exist equatorial regions oceans, in midlatitude continental regions, solid lands with low relative humidity. predicted viscosities are mostly consistent available measurements. free troposphere, particles be 850 hPa 500 hPa, except tropical Amazonia, where viscous. Phase also exhibits seasonal variation a higher frequency winter compared warmer seasons. We calculate equilibration time scales partitioning (τeq) effective mass accommodation coefficient (αeff), indicating τeq shorter than step GEOS-Chem 20 min αeff close unity for most locations level, supporting application equilibrium partitioning. However, prolonged lowered drylands upper suggesting kinetically limited growth would need considered these future large-scale model studies.

Language: Английский

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Incomplete mass closure in atmospheric nanoparticle growth

npj Climate and Atmospheric Science, Journal Year: 2025, Volume and Issue: 8(1)

Published: Feb. 26, 2025

Language: Английский

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Uptake of organic vapours and nitric acid on atmospheric freshly nucleated particles

Aerosol Research, Journal Year: 2025, Volume and Issue: 3(1), P. 125 - 137

Published: Feb. 28, 2025

Abstract. Sulfuric acid, ammonia, and amines are believed to be key contributors the initial steps in new particle formation atmosphere. However, other compounds such as organic or nitric acid important for further growth at larger sizes. In this study, we investigate potential uptake of first-generation oxidation products from α-pinene (pinic pinonic acid) isoprene (trans-β-IEPOX, β4-ISPOOH, β1-ISOPOOH), a highly oxidised molecule (HOM), formic acid. The is probed onto (SA)10(base)10 freshly nucleated particles (FNPs), where SA denotes sulfuric bases ammonia (AM), methylamine (MA), dimethylamine (DMA), trimethylamine (TMA). addition free energies were calculated ωB97X-D3BJ/6-311++G(3df,3pd)//B97-3c level theory. We find favourable −8 −10 kcal mol−1 HOM, pinic on less sterically hindered (SA)10(AM)10 (SA)10(MA)10 FNPs. This suggests that do not contribute early FNPs, but do, accordance with their expected volatilities. Calculating second maintains its large energy decrease due two carboxylic groups interacting monomer, well FNP. pinonic-acid drops −3.9 weak interactions between FNP carbonyl group lack monomer–monomer interactions. under realistic atmospheric conditions, FNPs studied too small (1.4 nm) support monomers. accretion product pinyl diaterpenylic ester (PDPE; C17H26O8) yields an value −17.1 mol−1. PDPE can overcome strong Kelvin effect 1.4 nm lead spontaneous ambient conditions.

Language: Английский

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The impact of the Himalayan aerosol factory: results from high resolution numerical modelling of pure biogenic nucleation over the Himalayan valleys

Faraday Discussions, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Observational data collected in December 2014 at the base camp of Mount Everest, Nepal, indicated frequent new particle formation events pure biogenic origin. Those were speculated to be controlled by along-valley winds forming valley connecting Indo-Gangetic plain observational site, Nepal Climate Observatory-Pyramid. The funnel highly oxygenated organic molecules origin higher elevations where they nucleate. mechanism was referred as "The Himalayan aerosol factory". Its geographical extent and climate implications are currently unknown. In view this, we conducted numerical chemical model simulations corroborate presence mechanism, quantify its extent. Our confirmed that emissions located valleys can converted into ultra-low volatility compounds, transported site winds, therein overall time scale process, from release conversion volatile compounds arrival found around 4 hours, consistent with predicted intensity distribution emissions. A first estimation maximum injection height particles, molecules, efficient nucleating gases particles an elevation high 5000-6000 m a.s.l. These results suggest chain, under specific weather conditions, is a main contributor loads free troposphere. Considering these findings, field campaigns, especially entrance valley's floors, research consortia supporting atmospheric Asian mountain regions, encouraged.

Language: Английский

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Humidity-resistant air filtration and passive respiratory sensing by direct metal–organic framework functionalization and nanopore generation at electroactive poly(lactic acid) nanofibers

Journal of environmental chemical engineering, Journal Year: 2025, Volume and Issue: 13(3), P. 116214 - 116214

Published: March 19, 2025

Language: Английский

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