European aerosol phenomenology − 8: Harmonised source apportionment of organic aerosol using 22 Year-long ACSM/AMS datasets

Environment International, Journal Year: 2022, Volume and Issue: 166, P. 107325 - 107325

Published: May 31, 2022

Organic aerosol (OA) is a key component of total submicron particulate matter (PM1), and comprehensive knowledge OA sources across Europe crucial to mitigate PM1 levels. has well-established air quality research infrastructure from which yearlong datasets using 21 chemical speciation monitors (ACSMs) 1 mass spectrometer (AMS) were gathered during 2013-2019. It includes 9 non-urban 13 urban sites. This study developed state-of-the-art source apportionment protocol analyse long-term spectrum data by applying the most advanced strategies (i.e., rolling PMF, ME-2, bootstrap). harmonised was followed strictly for all 22 datasets, making results more comparable. In addition, it enables quantification common components such as hydrocarbon-like (HOA), biomass burning (BBOA), cooking-like (COA), oxidised-oxygenated (MO-OOA), less (LO-OOA). Other coal combustion (CCOA), solid fuel (SFOA: mainly mixture peat combustion), cigarette smoke (CSOA), sea salt (mostly inorganic but part spectrum), coffee OA, ship industry could also be separated at few specific Oxygenated (OOA) make up (average = 71.1%, range 43.7 100%). Solid combustion-related BBOA, CCOA, SFOA) are still considerable with in 16.0% yearly contribution yet winter months (21.4%). Overall, this works effectively sites governed different generates robust consistent results. Our work presents overview unique combination high time resolution (30-240 min) coverage (9-36 months), providing essential information improve/validate quality, health impact, climate models.

Language: Английский

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

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(4), P. 1635 - 1679

Published: Jan. 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,

Language: Английский

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Role of sesquiterpenes in biogenic new particle formation

Science Advances, Journal Year: 2023, Volume and Issue: 9(36)

Published: Sept. 8, 2023

Biogenic vapors form new particles in the atmosphere, affecting global climate. The contributions of monoterpenes and isoprene to particle formation (NPF) have been extensively studied. However, sesquiterpenes received little attention despite a potentially important role due their high molecular weight. Via chamber experiments performed under atmospheric conditions, we report biogenic NPF resulting from oxidation pure mixtures β-caryophyllene, α-pinene, isoprene, which produces oxygenated compounds over wide range volatilities. We find that class termed ultralow-volatility organic (ULVOCs) are highly efficient nucleators quantitatively determine efficiency. When compared with mixture monoterpene alone, adding only 2% sesquiterpene increases ULVOC yield doubles rate. Thus, emissions need be included assessments aerosol concentrations pristine climates where is expected major source cloud condensation nuclei.

Language: Английский

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Modeling daytime and nighttime secondary organic aerosol formation via multiphase reactions of biogenic hydrocarbons

Atmospheric chemistry and physics, Journal Year: 2023, Volume and Issue: 23(2), P. 1209 - 1226

Published: Jan. 24, 2023

Abstract. The daytime oxidation of biogenic hydrocarbons is attributed to both OH radicals and O3, while nighttime chemistry dominated by the reaction with O3 NO3 radicals. Here, patterns secondary organic aerosol (SOA) originating from were predicted under varying environmental conditions (temperature, humidity, sunlight intensity, NOx levels, seed conditions) using UNIfied Partitioning Aerosol phase Reaction (UNIPAR) model, which comprises multiphase gas–particle partitioning in-particle chemistry. products atmospheric three different (isoprene, α-pinene, β-caryophyllene) extended semi-explicit mechanisms for four major oxidants (OH, NO3, O(3P)) during day night. resulting oxygenated then classified into volatility–reactivity-based lumping species. stoichiometric coefficients associated species dynamically constructed they applied UNIPAR SOA model. predictability model was demonstrated simulating chamber-generated data environments. For formation, isoprene α-pinene OH-radical-initiated showing a gradual increase in yields decreasing levels. formation processed mainly NO3-driven oxidation, yielding higher mass than at level (isoprene / < 5 ppb C ppb−1). At given amount ozone, produce gradually transited NO3-initiated ozonolysis as levels decreased. Nighttime also significantly yields, although decreased β-Caryophyllene, rapidly produced high showed relatively small variation changes (i.e., conditions, intensity), its generally more sensitive aqueous reactions because highly oxidized multifunctional products. simulation presence gasoline fuel, can compete typical urban air, suggested growth enhanced path. We concluded that hydrocarbon or source production sizable nocturnal SOA, despite low emission

Language: Английский

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High emission rates and strong temperature response make boreal wetlands a large source of isoprene and terpenes

Atmospheric chemistry and physics, Journal Year: 2023, Volume and Issue: 23(4), P. 2683 - 2698

Published: Feb. 27, 2023

Abstract. Wetlands cover only 3 % of the global land surface area, but boreal wetlands are experiencing an unprecedented warming four times average. These emit isoprene and terpenes (including monoterpenes (MT), sesquiterpenes (SQT), diterpenes (DT)), which climate-relevant highly reactive biogenic volatile organic compounds (BVOCs) with exponential dependence on temperature. In this study, we present ecosystem-scale eddy covariance (EC) fluxes isoprene, MT, SQT, DT (hereafter referred to together as terpenes) at Siikaneva, a fen in southern Finland, from start peak growing season 2021 (19 May 28 June 2021). first EC reported using novel state-of-the-art Vocus proton transfer reaction mass spectrometer (Vocus-PTR) first-ever for DTs wetland. Isoprene was dominant compound emitted by wetland, followed MTs, SQTs, DTs, they all exhibited strong temperature dependence. The Q10 values, factor terpene emissions increases every 10 ∘C rise temperature, were up five higher than those used most BVOC models. During campaign, air peaked above 31 21–22 2021, is abnormally high environments, maximum flux coincided period. We observed that elevated after “high-temperature stress period”, indicating past temperatures alter significantly. standardized emission (EF) (EFiso) 11.1 ± 0.3 nmol m−2 s−1, least two previous studies factors typical broadleaf other forests lower latitudes. EFMT 2.4 0.1 EFSQT 1.3 0.03 needle leaf tree functional types, EFDT 0.011 0.001 s−1. also compared landscape average model gases aerosols nature (MEGAN) v2.1 found underestimated over 9 300 800 SQTs. Our results show due very EFs sensitivity increasing temperatures, these high-latitude ecosystems can be large source atmosphere, anthropogenic could induce much future.

Language: Английский

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NH₃ Weakens the Enhancing Effect of SO₂ on Biogenic Secondary Organic Aerosol Formation

Environmental Science & Technology Letters, Journal Year: 2023, Volume and Issue: 10(2), P. 145 - 151

Published: Feb. 1, 2023

Anthropogenic air pollutants can be involved in biogenic secondary organic aerosol (SOA) formation. However, such interactions are currently one of the least understood aspects atmospheric chemistry. Herein, SOA formation via chemical between anthropogenic SO2, NH3, and O3 β-caryophyllene was investigated. It is shown that although SO2 considerably enhanced formation, this enhancing effect weakened by NH3 when coexisted. NH3-induced neutralization particle acidity generated oxidation may primary driving factor weakening effect. Molecular-level characterization using high-resolution quadrupole time-of-flight mass spectrometry revealed additional connections changes composition acidity. Specifically, lower relative abundances several main products presence than those formed only were consistent with their suppressed seed The suppression oligomer provided more evidence for acid-catalyzed processes caused neutralization. Accordingly, current study demonstrates as a less effectively regulated alkaline gas resulting from an unbalanced reduction different must considered caution evaluating effects on anthropogenic–biogenic interactions.

Language: Английский

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First eddy covariance flux measurements of semi-volatile organic compounds with the PTR3-TOF-MS

Atmospheric measurement techniques, Journal Year: 2021, Volume and Issue: 14(12), P. 8019 - 8039

Published: Dec. 23, 2021

Abstract. We present first eddy covariance flux measurements with the PTR3-TOF-MS, a novel proton transfer time of flight reaction mass spectrometer. During 3 weeks in spring 2016, instrument recorded 10 Hz data biogenic volatile organic compounds above boreal forest, on top measurement tower at SMEAR (Station for Measuring Ecosystem –Atmosphere Relations) II station Hyytiälä, Finland. Flux and concentration isoprene, monoterpenes, sesquiterpenes were compared to literature. Due improved sensitivity customized wall-less inlet design, we could detect fluxes semi-volatile low-volatility less than single-digit picomol per square meter second (pmolm-2s-1) values time. These include sesquiterpene oxidation products diterpenes. Daytime diterpene range 0.05 0.15 pmolm-2s-1, which amounts about 0.25 % 0.5 daytime canopy.

Language: Английский

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Chemical Quality and Characterization of Essential Oils in Postharvest Hop cv. Cascade: Ventilated Room Temperature as a Sustainable Alternative to Hot-Stove and Freeze-Drying Processes

Beverages, Journal Year: 2025, Volume and Issue: 11(2), P. 54 - 54

Published: April 18, 2025

Hop is a key ingredient in beer production, and drying it allows to be stored before use. Unfortunately, postharvest techniques can negatively affect hop quality. In this study, we compared using hot stove (H), freeze-drying (F), ventilated at room temperature (VRT) drying, focusing on the chemical quality essential oil composition. To achieve 80% water removal, F H took two days, while VRT five days. preserved high content of total chlorophyll (F 81.89 g/kg dm; 82.70 dm) carotenoids 54.02 54.71 dm). The storage index (HSI) increased with all techniques, but especially H. lowest amount polyphenols was found sample (348.48 dm), highest (631.11 Freeze-drying gave best results, relation antioxidant power product. Regarding oils, class sesquiterpene hydrocarbons, α-humulene 24.0%; 24.7%; 25.6%), β-caryophyllene 10.5%; 9.4%; 11.1%), β-farnesene 6.8%; 6.0%; 7.4%). monoterpene hydrocarbon sample. Thus, emerges as an alternative technique stove; however, cost high. Instead, represents sustainable valid for preserving aromatic characteristics

Language: Английский

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A Review of Biogenic Volatile Organic Compounds from Plants: Research Progress and Future Prospects

Toxics, Journal Year: 2025, Volume and Issue: 13(5), P. 364 - 364

Published: April 30, 2025

Biogenic volatile organic compounds (BVOCs) emitted by plants contribute to secondary air pollution through photochemical reactions in sunlight. Due the influence of multiple factors, accurately characterizing and quantifying emission BVOCs from plant sources is challenging, which poses significant obstacles effective management control BVOCs. Therefore, this paper summarizes mechanisms plants, explores primary factors influencing variations rates these compounds, evaluates advantages limitations contemporary “measurement-modeling” methods for BVOC emissions. It concluded that current measurement techniques still need be further developed meet criteria simplicity, affordability, high precision simultaneously, terms modeling prediction studies, there a lack in-depth research on atmospheric chemistry synergistic effects factors. Finally, it suggested leverage interdisciplinary strengths develop advanced technologies high-resolution models monitoring compounds. Additionally, strategically selecting low-BVOC tree species pollution-vulnerable urban areas—contingent rigorous ecological assessments—combined with stringent controls anthropogenic precursors (e.g., (AVOCs)) could serve as complementary measure mitigate pollution.

Language: Английский

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Volatility of Secondary Organic Aerosol from β-Caryophyllene Ozonolysis over a Wide Tropospheric Temperature Range

Environmental Science & Technology, Journal Year: 2023, Volume and Issue: 57(24), P. 8965 - 8974

Published: June 7, 2023

We investigated secondary organic aerosol (SOA) from β-caryophyllene oxidation generated over a wide tropospheric temperature range (213–313 K) ozonolysis. Positive matrix factorization (PMF) was used to deconvolute the desorption data (thermograms) of SOA products detected by chemical ionization mass spectrometer (FIGAERO-CIMS). A nonmonotonic dependence particle volatility (saturation concentration at 298 K, C298K*) on formation observed, primarily due temperature-dependent pathways products. The PMF analysis grouped ions into 11 compound groups (factors) with characteristic volatility. These act as indicators for underlying mechanisms. Their different responses revealed that relevant (e.g., autoxidation, oligomer formation, and isomer formation) had distinct optimal temperatures between 213 313 significantly beyond effect partitioning. Furthermore, PMF-resolved were compared basis set (VBS) distributions based vapor pressure estimation methods. variation volatilities predicted methods is affected highly oxygenated molecules, isomers, thermal decomposition oligomers long carbon chains. This work distinguishes multiple isomers identifies varying volatilities, providing new insights mechanisms β-caryophyllene-derived particles.

Language: Английский

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