Insufficient Condensable Organic Vapors Lead to Slow Growth of New Particles in an Urban Environment

Environmental Science & Technology, Год журнала: 2022, Номер 56(14), С. 9936 - 9946

Опубликована: Июнь 24, 2022

Atmospheric new particle formation significantly affects global climate and air quality after newly formed particles grow above ∼50 nm. In polluted urban atmospheres with 1-3 orders of magnitude higher rates than those in clean atmospheres, growth are comparable or even lower for reasons that were previously unclear. Here, we address the slow Beijing advanced measurements size-resolved molecular composition nanoparticles using thermal desorption chemical ionization mass spectrometer gas precursors nitrate CI-APi-ToF. A model combining condensational particle-phase acid-base chemistry was developed to explore mechanisms. The 8-40 nm during events is dominated by organics (∼80%) sulfate (∼13%), remainder from base compounds, nitrate, chloride. With increase sizes, fraction decreases, while slow-desorbed organics, organic acids, increases. simulated consistent measured results most cases, they both indicate vapors H2SO4 major pathway reactions play a minor role. comparison high concentrations gaseous sulfuric acid amines cause rates, concentration condensable comparably under NOx levels, relatively high-volatility nitrogen-containing oxidation products higher. insufficient lead growth, which further causes low survival environments. Thus, some extent, counteract impact on

Язык: Английский

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The missing base molecules in atmospheric acid–base nucleation

National Science Review, Год журнала: 2022, Номер 9(10)

Опубликована: Июль 25, 2022

Transformation of low-volatility gaseous precursors to new particles affects aerosol number concentration, cloud formation and hence the climate. The clustering acid base molecules is a major mechanism driving fast nucleation initial growth in atmosphere. However, acid-base cluster composition, measured using state-of-the-art mass spectrometers, cannot explain high rate particles. Here we present strong evidence for existence such as amines smallest atmospheric sulfuric clusters prior their detection by spectrometers. We demonstrate that forming (H2SO4)1(amine)1 rate-limiting step H2SO4-amine uptake pathway H2SO4 clusters. proposed very consistent with particle urban Beijing, which dimethylamine key while other bases ammonia may contribute larger Our findings further underline fact amines, even at low concentrations when undetected clusters, can be crucial planetary boundary layer.

Язык: Английский

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Emissions of Ammonia and Other Nitrogen-Containing Volatile Organic Compounds from Motor Vehicles under Low-Speed Driving Conditions

Environmental Science & Technology, Год журнала: 2022, Номер 56(9), С. 5440 - 5447

Опубликована: Апрель 11, 2022

Emissions of NH3 and nine nitrogen-containing volatile organic compounds (NVOCs) (C1–3-amines, C1–3-amides, C1–3-imines) from motor vehicles powered by gasoline, diesel, natural gas under low-speed driving conditions roadside in situ measurements were characterized using a water-cluster chemical ionization mass spectrometer trace monitors. The total emission strength diesel trucks was the greatest followed those gasoline cars cars. per vehicle found to be 2–3 orders magnitude greater than that all NVOCs, regardless type vehicle. Although much lower emissions amides or imines, amines sufficient produce atmospheric concentrations exceeding threshold level for enhance nucleation several magnitude. Different engine reduction technologies (e.g., three-way catalytic converter vs selective reduction) can lead different NVOC profiles. During lifetime vehicle, its most likely increase with mileage. Source profiles three types also obtained measurements. These valuable contribution air pollution management system terms source apportionment, elucidating contributions specific

Язык: Английский

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Role of sesquiterpenes in biogenic new particle formation

Science Advances, Год журнала: 2023, Номер 9(36)

Опубликована: Сен. 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.

Язык: Английский

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Significant contributions of trimethylamine to sulfuric acid nucleation in polluted environments

npj Climate and Atmospheric Science, Год журнала: 2023, Номер 6(1)

Опубликована: Июнь 27, 2023

Abstract As one of the least understood aerosol processes, nucleation can be a dominant source atmospheric aerosols. Sulfuric acid (SA)-amine binary with dimethylamine (DMA) has been recognized as governing mechanism in polluted continental boundary layer. Here we demonstrate importance trimethylamine (TMA) for complex atmosphere and propose molecular-level SA-DMA-TMA ternary an improvement upon conventional mechanism. Using proposed mechanism, could connect gaseous amines to SA-amine cluster signals measured urban Beijing. Results show that TMA accelerate SA-DMA-based new particle formation Beijing by 50–100%. Considering global abundance DMA, our findings imply comparable DMA layer, probably higher contributions from rural environments future controlled emissions.

Язык: Английский

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Dynamics of nanocluster aerosol in the indoor atmosphere during gas cooking

PNAS Nexus, Год журнала: 2024, Номер 3(2)

Опубликована: Фев. 1, 2024

Nanocluster aerosol (NCA: particles in the size range of 1-3 nm) are a critically important, yet understudied, class atmospheric particles. NCA efficiently deposit human respiratory system and can translocate to vital organs. Due their high surface area-to-mass ratios, associated with heightened propensity for bioactivity toxicity. Despite health relevance NCA, little is known regarding prevalence indoor environments where people spend majority time. In this study, we quantify formation transformation down 1 nm via high-resolution online nanoparticle measurements during propane gas cooking residential building. We observed substantial pool sub-1.5 atmosphere periods, number concentrations often dominated by newly formed NCA. Indoor emission factors reach up ∼10

Язык: Английский

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Overlooked significance of iodic acid in new particle formation in the continental atmosphere

Proceedings of the National Academy of Sciences, Год журнала: 2024, Номер 121(31)

Опубликована: Июль 24, 2024

New particle formation (NPF) substantially affects the global radiation balance and climate. Iodic acid (IA) is a key marine NPF driver that recently has also been detected inland. However, its impact on continental nucleation remains unclear. Here, we provide molecular-level evidence IA greatly facilitates clustering of two typical land-based nucleating precursors: dimethylamine (DMA) sulfuric (SA), thereby enhancing nucleation. Incorporating this mechanism into an atmospheric chemical transport model, show IA-induced enhancement could realize increase over 20% in SA–DMA rate iodine-rich regions China. With declining anthropogenic pollution driven by carbon neutrality clean air policies China, enhance rates 1.5 to 50 times 2060. Our results demonstrate overlooked role highlight necessity for considering synergistic SA-IA-DMA modeling correct representation climatic impacts aerosols.

Язык: Английский

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Size-resolved particle number emissions in Beijing determined from measured particle size distributions

Atmospheric chemistry and physics, Год журнала: 2020, Номер 20(19), С. 11329 - 11348

Опубликована: Окт. 5, 2020

Abstract. The climate and air quality effects of aerosol particles depend on the number size particles. In urban environments, a large fraction originates from anthropogenic emissions. To evaluate different pollution sources quality, knowledge distributions particle emissions is needed. Here we introduce novel method for determining size-resolved emissions, based measured distributions. We apply our to data in Beijing, China, determine distribution emitted diameter range 2 1000 nm. observed are dominated by smaller than 30 Our results suggest that traffic major source with highest around 10 nm during rush hours. At sizes below 6 nm, clustering atmospheric vapors contributes calculated comparison between those estimated an integrated assessment model GAINS (Greenhouse Gas Air Pollution Interactions Synergies) shows yields clearly higher at 60 but above two methods agree well. Overall, proven be useful tool gaining new environments validating emission inventories models. future, will developed modeling transport obtain more accurate estimates

Язык: Английский

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An indicator for sulfuric acid–amine nucleation in atmospheric environments

Aerosol Science and Technology, Год журнала: 2021, Номер 55(9), С. 1059 - 1069

Опубликована: Май 2, 2021

New particle formation (NPF) occurs frequently in various atmospheric environments and it is a major source of ultrafine particles. This study proposes an indicator, I, for the occurrence NPF atmosphere based on mechanism H2SO4–amine nucleation. It characterizes synergistic effects governing factors nucleation, including H2SO4 concentration, amine concentrations, stability clusters, aerosol surface area concentration. Long-term measurements urban Beijing were used to validate this indicator. Good consistency was found between indicator NPF. usually observed with I > 1 typical conditions Beijing. The derivation expressions also indicate good positive association dimer concentration NPF, as verified by measurements. shown be applicable Shanghai.Copyright © 2021 American Association Aerosol Research

Язык: Английский

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Composition of Ultrafine Particles in Urban Beijing: Measurement Using a Thermal Desorption Chemical Ionization Mass Spectrometer

Environmental Science & Technology, Год журнала: 2021, Номер 55(5), С. 2859 - 2868

Опубликована: Фев. 12, 2021

Ultrafine particles (UFPs) dominate the particle number population in urban atmosphere and revealing their chemical composition is important. The thermal desorption ionization mass spectrometer (TDCIMS) can semicontinuously measure UFP at molecular level. We modified a TDCIMS deployed it Beijing. Radioactive materials for aerosol charging were replaced by soft X-ray ionizers so that be operated countries with tight regulations on radioactive materials. Protonated N-methyl-2-pyrrolidone ions used as positive reagent ion, which selectively detects ammonia low-molecular weight-aliphatic amines amides vaporized from phase. With superoxide negative wide range of inorganic organic compounds observed, including nitrate, sulfate, aliphatic acids carbon numbers up to 18, highly oxygenated CHO, CHON, CHOS compounds. latter two attributed parent or decomposition products organonitrates organosulfates/organosulfonates, respectively. Components both primary emissions secondary formation UFPs identified. Compared measured forest marine sites, those Beijing contain more nitrogen-containing sulfur-containing These observations illustrate unique features environment provide insights into origins.

Язык: Английский

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