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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Two-dimensional p-n heterojunctions of black phosphorus nanosheet-sensitized α-MoO3 nanoflake for low-temperature chemiresistive NH3 recognition

Microchemical Journal, Год журнала: 2024, Номер unknown, С. 111911 - 111911

Опубликована: Окт. 1, 2024

Язык: Английский

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Observation and Source Apportionment of Atmospheric Alkaline Gases in Urban Beijing

Environmental Science & Technology, Год журнала: 2022, Номер 56(24), С. 17545 - 17555

Опубликована: Ноя. 28, 2022

Alkaline gases, including NH3, C1–3-amines, C1–3-amides, and C1–3-imines, were measured in situ using a water cluster-CIMS urban Beijing during the wintertime of 2018, with campaign average 2.8 ± 2.0 ppbv, 5.2 4.3, 101.1 94.5, 5.4 pptv, respectively. Source apportionment analysis constrained by emission profiles in-use motor vehicles was performed SoFi-PMF software package, five sources identified as gasoline-powered (GV), diesel-powered (DV), septic system (SS), soil (SE), combustion-related (CS). SS dominant NH3 source (60.0%), followed DV (18.6%), SE (13.1%), CS (4.3%), GV (4.0%). responsible for 69.9 85.2% C1- C2-amines emissions, Most C3-amines emitted from nonmotor vehicular (SS = 61.3%; 17.8%; 9.1%). accounted 71.9 34.1% C2-amides mainly comprised amides imines, likely originating pyrolysis nitrogen-containing compounds. Our results suggested that vehicle exhausts can not only contribute to criteria air pollutants but also promote new particle formation, which has been well recognized considered current regulations. Urban residential predominant contributor background NH3. Enhanced emissions major cause PM2.5 buildup haze events. Combustion-related sources, together vehicles, most observed imines may be public health concern within vicinity these sources.

Язык: Английский

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A new advance in the pollution profile, transformation process, and contribution to aerosol formation and aging of atmospheric amines

Environmental Science Atmospheres, Год журнала: 2023, Номер 3(3), С. 444 - 473

Опубликована: Янв. 1, 2023

Atmospheric amines from various sources undergo a variety of homogeneous and heterogeneous reactions to contribute the overall process aerosol particle formation further affect climate.

Язык: Английский

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A [Cu₂O₂]²⁺ Core in Cu/ZSM-5 for Efficient Selective Catalytic Oxidation of Nitrogen-Containing VOCs and NH₃

ACS ES&T Engineering, Год журнала: 2024, Номер 4(5), С. 1016 - 1027

Опубликована: Фев. 5, 2024

Highly efficient elimination of nitrogen-containing volatile organic compounds (NVOCs) or NH3 via selective catalytic oxidation (SCO) while avoiding NOx is a strongly desired process for their control. However, limited by lack fundamental guidance such as accurate active site and reaction mechanisms, the targeted design high-performance catalysts faces severe challenges. Herein, ZSM-5 zeolites supported different copper species were used in SCO dimethylformamide (DMF) NH3. Optimal 8% Cu/ZSM-5 had highest N2 selectivity above 94%. Various situ spectroscopic characterizations DFT theoretical calculations precisely identified that μ-(η2:η2)-peroxo dicopper (bent; [Cu2O2]2+) core, which associated with two Al sites separated three SiO4 tetrahedra units 10-membered ring ZSM-5. The dynamic behavior DMF-SCO was revealed to be [Cu2O2]2+ transformed into mono-(μ-oxo) upon DMF adsorption, opposite occurred when O2 attacked. In DRIFTS elucidated pathway indicated disassociating N–H bond rate-determining step transforming N2. This work not only points way NVOCs but provides methodological implications study structures.

Язык: Английский

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Progress of ammonia selective catalytic oxidation research and performance improvement strategy

Journal of environmental chemical engineering, Год журнала: 2024, Номер 12(2), С. 112306 - 112306

Опубликована: Фев. 23, 2024

Язык: Английский

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Ammonia Abatement via Selective Oxidation over Electron-Deficient Copper Catalysts

Environmental Science & Technology, Год журнала: 2022, Номер 56(19), С. 14008 - 14018

Опубликована: Сен. 13, 2022

Selective catalytic ammonia-to-dinitrogen oxidation (NH3-SCO) is highly promising for the abatement of NH3 emissions from flue gas purification devices. However, there still a lack high-performance and cost-effective NH3-SCO catalysts real applications. Here, dispersed, electron-deficient Cu-based were fabricated using nitrogen-doped carbon nanotubes (NCNT) as support. In catalysis, Cu/NCNT outperformed Cu supported on N-free CNTs (Cu/OCNT) other types supports (i.e., activated carbon, Al2O3, zeolite) in terms activity, selectivity to desired product N2, H2O resistance. Besides, demonstrated better structural stability against higher storage capacity (in presence vapor) than Cu/OCNT. Quasi situ X-ray photoelectron spectroscopy revealed that surface N species facilitated electron transfer NCNT support, resulting with superior redox properties, which are essential catalysis. By temperature-programmed reaction studies systematic kinetic measurements, we unveiled over proceeded via internal selective (i-SCR) route; i.e., was oxidized first NO, then reacted O2 form N2 H2O. This study paves new route design active, H2O-tolerant, low-cost slip stationary N2.

Язык: Английский

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A dynamic parameterization of sulfuric acid–dimethylamine nucleation and its application in three-dimensional modeling

Atmospheric chemistry and physics, Год журнала: 2023, Номер 23(15), С. 8789 - 8804

Опубликована: Авг. 9, 2023

Abstract. Sulfuric acid (SA) is a governing gaseous precursor for atmospheric new particle formation (NPF), major source of global ultrafine particles, in environments studied around the world. In polluted urban atmospheres with high condensation sinks (CSs), stable SA–amine clusters, such as SA–dimethylamine (DMA) usually initializes intense NPF events. Coagulation scavenging and cluster evaporation are dominant sink processes clusters atmospheres, yet these loss not quantitatively included present parameterizations nucleation. We herein report parameterization SA–DMA nucleation, based on dynamic simulations quantum chemistry calculations, certain simplifications to greatly reduce computational costs. Compared previous nucleation parameterizations, this was able reproduce dependences rates temperature CSs. then incorporated it three-dimensional (3-D) chemical transport model simulate evolution number size distributions. Simulation results showed good consistency observations occurrence events distributions wintertime Beijing represented significant improvement compared that using without coagulation scavenging. Quantitative analysis shows contributes significantly aerosol population during 3-D (>99 % >60 %, respectively). These broaden understanding stress necessity including effects stability simulating simulations. Representing thus likely improve performance apportionment quantification air quality, human health, climate.

Язык: Английский

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Mist cannon trucks can exacerbate the formation of water-soluble organic aerosol and PM_2.5 pollution in the road environment

Atmospheric chemistry and physics, Год журнала: 2023, Номер 23(12), С. 6775 - 6788

Опубликована: Июнь 20, 2023

Abstract. Mist cannon trucks have been widely applied in megacities China to reduce the road dust, since they are considered be more water saving and efficient than traditional sprinkling trucks. However, their effect on formation of water-soluble organic compounds pollution control fine particles (PM2.5) remains unknown. We characterized variations chemical compositions PM2.5 collected sides during simulated operations mist truck via Fourier transform ion cyclotron resonance mass spectrometry chromatography. The concentrations carbon showed a significant increase (62 %–70 %) after air spraying. Furthermore, we found that compounds, particularly nitrates, increased significantly interactions reactive gas-phase organics, atmospheric oxidants aerosol liquid spraying, although spraying had better suppressing dust ground aspersion. Moreover, segment where passed by was promoted, with an up 13 % concentration 25–35 min, average. Thus, application potentially worsens environment through levels production large number PM2.5. overall results provide not only valuable insights processes associated but also management strategies regulate operation China.

Язык: Английский

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Seasonal characterization of chemical and optical properties of water-soluble organic aerosol in Beijing

The Science of The Total Environment, Год журнала: 2024, Номер 930, С. 172508 - 172508

Опубликована: Апрель 18, 2024

Язык: Английский

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