Significant NO₂ Formation in Truck Exhaust Plumes and Its Association with Ambient O₃: Evidence from Extensive Plume-Chasing Measurements

Environmental Science & Technology, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 10, 2025

Vehicle nitrogen oxides (NOx) significantly increase dioxide (NO2) exposure in traffic-related environments. The NO2/NOx ratios are crucial for accurate NO2 modeling and closely linked to public health concerns. In 2020, we used a mobile platform follow test trucks (plume-chasing) that were installed with portable emission measuring system (PEMS) on two restricted driving tracts. Six hundred eighteen exhaust plumes collected through the PEMS-chasing measurements from seven trucks. NOx factors (EFs), ratios, calculated at distinct stages (i.e., tailpipe on-road). A significant reduction EFs (>64%) was observed normal operating after-treatment devices, except equipped diesel particulate filter (DPF). Disparities also found, attributed technologies. measured plume-chasing higher (3–4 times, p < 0.001) than measurements, providing field evidence of substantial formation plumes. We developed quantitative relationship between demonstrated robust correlation (R2 > 0.90). Since plume is not explicitly accounted modeling, (O3–NO2/NOx) could improve estimation when local inventory (tailpipe emissions) available.

Language: Английский

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Upgrading Passenger Vehicle Emission Standard Helps to Reduce China’s Air Pollution Risk from Uncertainty in Electrification

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(12), P. 5325 - 5335

Published: Feb. 27, 2024

Upgrading to the CHINA 7 standard is crucial for managing air pollution from passenger vehicles in China. Meanwhile, China aims achieve carbon neutrality by 2060, which necessitates large-scale replacement of gasoline with electric future. Consequently, public might view upgrading as redundant. However, emission reduction benefits standards context uncertain electrification ambitions have not received adequate attention. Here, we show that will compensate absence emissions reductions due hindered efforts. In best scenario, China's CO2 can be reduced 0.047 Gt and NOx 8.2 × 103 t 2050. nonextreme scenarios standard, intensity remain main driver reductions, outweighing contribution. extreme scenarios, tackle increased plug-in hybrid vehicles. Our fleet-level results advocate early upgrades enhance resilience against risks arising uncertainties electrification. evidence China, one most stringent standards, provide a reference point world on vehicle issue.

Language: Английский

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Health benefits of vehicle electrification through air pollution in Shanghai, China

The Science of The Total Environment, Journal Year: 2024, Volume and Issue: 914, P. 169859 - 169859

Published: Jan. 6, 2024

Vehicle electrification has been recognized for its potential to reduce emissions of air pollutants and greenhouse gases in China. Several studies have estimated how national-level policies electric vehicle (EV) adoption might bring very large environmental public health benefits from improved quality However, large-scale is costly, some regions derive more EV than others, the replacing internal combustion engines specific cities are less known. Therefore, it important policymakers design incentives based on regional characteristics - especially megacities like Shanghai which typically suffer worse where a larger population exposed vehicles. Over past five years, offered substantial personal subsidies passenger EVs accelerate efforts. Still, remains uncertain whether justify strength incentives. The purpose our study evaluate climate light-duty gasoline vehicles (ICEVs) with battery city Shanghai. We assess impacts due ICEV primary fine particulate matter, NO

Language: Английский

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Enhanced Catalytic Oxidation Reactivity over Atomically Dispersed Pt/CeO₂ Catalysts by CO Activation

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(27), P. 12201 - 12211

Published: June 27, 2024

The elevation of the low-temperature oxidation activity for Pt/CeO2 catalysts is challenging to meet increasingly stringent requirements effectively eliminating carbon monoxide (CO) from automobile exhaust. Although reducing activation a facile strategy boosting reactivity, past research has mainly concentrated on applying H2 as reductant, ignoring reduction capabilities CO itself, prevalent component Herein, atomically dispersed was fabricated and activated by CO, which could lower 90% conversion temperature (T90) 256 °C achieve 20-fold higher consumption rate at 200 °C. showed exceptional catalytic robust hydrothermal stability under simulated working conditions gasoline or diesel exhausts. Characterization results illustrated that triggered formation large portion Pt0 terrace sites, acting inherent active sites oxidation. Besides, weakened Pt–O–Ce bond strength generate surface oxygen vacancy (Vo). It served reservoir store dissociated convert it into dioxygen intermediates. Conversely, failed stimulate Vo, but deactivating transformation Pt nanocluster inactive PtxOy in presence oxygen. present work offers coherent insight upsurging effect Pt/CeO2, aiming set up valuable avenue elevating efficiency C3H6, NH3

Language: Английский

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Spatiotemporal Distribution Characteristics and Inventory Analysis of Near-Road Traffic Pollution in Urban Areas

Atmosphere, Journal Year: 2024, Volume and Issue: 15(4), P. 417 - 417

Published: March 27, 2024

Vehicle emissions belong to the category of near-surface sources, occur close human activity areas, and pose a greater threat health than other anthropogenic pollution sources. Furthermore, study spatiotemporal characteristics near-road traffic is great significance urban regional ambient air quality management, also an important basis for vehicle emission inventories, as well assessment impact. Most previous studies have analyzed hydrocarbons (HCs), carbon monoxide (CO), nitrogen oxides (NOx), dioxide (CO2) in over certain time, without considering synergistic effect mobile source particulate matter, NOx, volatile organic compounds (VOCs). In this study, we analyze composition vehicles with different standards from road sources Anqing City, China. National III IV are main contribution various pollutants, accounting more 60% emissions. Although national I II accounted less 1% total number vehicles, their cannot be ignored, especially CO HCs, which such can reach about 7%. This mainly due low level control arising larger factor age these vehicles. eliminating old cars increasing proportion VI effectively reduce pollutant terms distribution characteristics, highways around areas heavy intensity pollutants higher on roads surrounding areas. addition, presence m/p-xylene toluene solvent-using species detected, indicates that petrol emissions, LPG volatilization, contribute significantly ozone formation process. Comparing weekdays non-weekdays, PM2.5 peaks non-weekdays those weekdays, there no “weekend effect”, little influence may related energy use industrial pollution. Overall, strengthens understanding relationship between volumes, types spatial temporal scales, emphasizes need further investigation comprehensive measures mitigate

Language: Английский

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Socioeconomic Inequalities in PM_2.5 Exposure and Local Source Contributions at Community Scales Using Hyper-Localized Taxi-Based Mobile Monitoring in Xi’an, China

Environmental Science & Technology, Journal Year: 2025, Volume and Issue: unknown

Published: March 12, 2025

The relationship between the socioeconomic status (SES) and PM2.5 exposure is rather inconclusive. We employed taxi-based measurements with 30 m resolution to characterize local source contribution (PM2.5 adjusted concentration) discerned for 2019 winter 2020 summer, in Xi'an. A big data set comprising ∼6 × 106 hourly SES from ∼5000 communities was utilized examine inequalities community-level exposure. Our results indicate that inhabitants lower are more likely be disproportionately exposed compared those higher SES. At least 92% of rural regions reside low areas, whereas a relatively smaller proportion (69–78%) urban regions. has profound impact on during summer than winter. polluted areas concentration accounted 22% 26% total However, residing low-concentration contributed only 12% while 30%. These findings provide valuable insights into SES, highlighting need sophisticated air quality policies alleviate

Language: Английский

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Reducing the road freight emissions through integrated strategy in the port cities

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: March 15, 2025

Port cities, as crucial nodes in global supply chains, face challenges from both intense traffic emissions and vulnerability to climate-related extremes due pollution density. Effective near-term mitigation strategies for greener road freight are imperative reverse the increasing trend of emissions. This study utilizes a high-resolution emission inventory 1.2 billion positioning system trajectories heavy-duty trucks Shenzhen, port city, evaluate combined effects network development fleet electrification on 2016 2035, providing basis policy interventions applicable various urban contexts. Our findings reveal that an integrated strategy decreases emissions, cutting peak carbon dioxide nitrogen oxide by 34% 43%, respectively, compared electrification-only scenarios. While supported net-zero grids is necessary, it insufficient without addressing congestion enhancing connectivity through expanded networks. Spatial projections also assist targeted policymaking showing how distributions shift with regional expansion. reveals reduction potential cities. It demonstrates significantly reduces alone.

Language: Английский

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Heavy-Duty Diesel Trucks on Highways in Beijing-Tianjin-Hebei: Constant Challenge in Pollution Control

Water Air & Soil Pollution, Journal Year: 2025, Volume and Issue: 236(6)

Published: April 22, 2025

Language: Английский

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Multi-perspective analysis of long-term vehicle emissions under intensive policy updates in China

Transportation Research Part D Transport and Environment, Journal Year: 2025, Volume and Issue: 145, P. 104808 - 104808

Published: May 19, 2025

Language: Английский

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Spatial and Cross-Sectoral Transfer of Air Pollutant Emissions from the Fleet Electrification in China by 2030

Environmental Science & Technology, Journal Year: 2023, Volume and Issue: 57(50), P. 21249 - 21259

Published: Dec. 6, 2023

Fleet electrification shifts emission sources from the tailpipe to electricity generation and automotive supply chains subsequently, with transfer among regions. Such a spatial cross-sectoral of air pollutant emissions might embody uncertain environmental benefits spatially, which has not been comprehensively quantified, mainly due complexity manufacturing processes electric vehicle (EV) components (e.g., battery). We developed hybrid life cycle assessment by combining inventory data major input-output information identified how China's EV deployment would influence redistribution currently (2017) in future (2030). The results indicate that fleet could readily reduce nitrogen oxides (NOx) nonmethane volatile organic compound (NMVOC) 12-93%, reductions are estimated be concentrated cities urban agglomerations. However, increased demand for power battery production increase PM2.5 SO2 17-55% grids under all scenarios, emerge coal-rich Inner Mongolia, Shanxi) industrial Shandong, Henan, Jiangsu) provinces. By tracing upstream, 31-55% vehicle-cycle deep but exhibit diverse sources. It suggests necessity relieve leakage synchronizing effective management across multiple sectors through chains.

Language: Английский

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