Article
Engineering, Environmental
Yu Gan, Zifeng Lu, Qingru Wu, Xin He, Qiang Dai, Jarod C. Kelly, Sharath K. Ankathi, Michael Wang
Summary: China's promotion of vehicle electrification has led to an increase in mercury emissions. With current technologies, the life-cycle mercury emissions of battery electric vehicles are 92% higher than conventional gasoline vehicles, primarily due to high mercury emissions from coal-based electricity generation. Measures such as decarbonizing the electric grid and implementing mercury-specific emission control can help mitigate this unintended increase in mercury emissions caused by vehicle electrification.
RESOURCES CONSERVATION AND RECYCLING
(2023)
Article
Engineering, Environmental
Han Jiang, Hefeng Zhang, Haiguang Zhao, Mingliang Fu, Yunjing Wang, Xian Wu, Xinping Yang, Jianglin Ji, Hang Yin, Yan Ding
Summary: Ammonia emissions from motor vehicles have significant impacts on air pollution and human health in urban areas. Research has focused on measuring and controlling ammonia emissions from light-duty gasoline vehicles (LDGVs). Analysis of ammonia emissions characteristics showed that they were mainly concentrated in low and medium speed sections during the cold-start stage. The temperature and load conditions were found to affect ammonia emissions, with higher ambient temperatures leading to lower emissions but extremely elevated ambient temperature causing obvious emissions. Study of various factors' effects on ammonia emissions is important for understanding its formation conditions and supporting future regulations.
JOURNAL OF HAZARDOUS MATERIALS
(2023)
Article
Environmental Sciences
Yan Xia, Linhui Jiang, Lu Wang, Xue Chen, Jianjie Ye, Tangyan Hou, Liqiang Wang, Yibo Zhang, Mengying Li, Zhen Li, Zhe Song, Yaping Jiang, Weiping Liu, Pengfei Li, Daniel Rosenfeld, John H. Seinfeld, Shaocai Yu
Summary: In-time and accurate assessment of on-road vehicle emissions is crucial for urban air quality and health policymaking. However, the current Inspection/Maintenance (I/M) procedure has limitations. In this study, we built a unique dataset and developed an ensemble model framework using machine learning algorithms to assess vehicle-specific emissions. The model performed well under normal conditions and could provide day-to-day supervision of on-road vehicle emissions.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Studies
Weichang Yuan, Christopher Frey, Tongchuan Wei
Summary: Eco-driving has the potential to reduce fuel consumption and emissions for light-duty gasoline vehicles. This study quantifies the potential reduction of fuel consumption and emission rates at the route and segment level through eco-driving. The results show that eco-driving can reduce fuel consumption and emission rates by 6-40% compared to average rates. Moreover, eco-driving typically reduces air emissions and may also reduce segment-level fuel consumption and emission rates.
TRANSPORTATION RESEARCH PART D-TRANSPORT AND ENVIRONMENT
(2022)
Article
Meteorology & Atmospheric Sciences
B. S. Arun, Mukunda M. Gogoi, Arup Borgohain, Prashant Hegde, Shyam Sundar Kundu, S. Suresh Babu
Summary: The study of aerosols in the remote high-altitude site in the eastern Himalayas revealed the significant contribution of sulphate and carbonaceous aerosols to the total aerosol mass loading in winter and spring, resulting in high scattering and absorption coefficients. The seasonal aerosol direct radiative forcing was as high as -2.9 Wm-2 in winter and -2.8 Wm-2 in spring, with the combined effect of carbonaceous and sulphate aerosols causing the highest surface cooling in spring.
ATMOSPHERIC RESEARCH
(2021)
Article
Environmental Sciences
Fei Yu, Zhuangmin Zhong, Qun Wang, Songdi Liao, Manni Zhu, Qing'e Sha, Junwen Liu, Junyu Zheng
Summary: This study investigates the factors influencing vehicle particle number (PN) emissions and suggests measures to reduce particulate emissions. The impact of engine technology, emission standards, engine-start conditions, and engine load on PN emissions were quantified through real driving emission (RDE) and chassis dynamometer tests. The results highlight the importance of optimizing gasoline particle filters (GPF) regeneration conditions and considering vehicle specific power (VSP) as a key variable in quantifying PN emissions.
ENVIRONMENTAL RESEARCH
(2022)
Article
Engineering, Multidisciplinary
Meng Jiang, Xiaowei Liu, Jinke Han, Zijian Zhou, Minghou Xu
Summary: The combined extinction and scattering method has been proven to be reliable in measuring particle size and concentration for spherical silica particles. However, when applied to non-spherical particles, such as irregularly-shaped silica particles, more fluctuations were observed in the correlation between the experimentally-derived extinction-to-scattering ratio and aerodynamic size, leading to higher deviation from the nominal values. Despite these fluctuations, the relative error in the size-corrected extinction coefficient remains within +/- 20% in the investigated size range for irregularly-shaped silica particles.
Article
Environmental Sciences
Jiangchuan Hu, H. Christopher Frey, Behdad Yazdani Boroujeni
Summary: For light-duty gasoline vehicles equipped with catalytic converters, hot-stabilized tailpipe emissions of carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) are well controlled. However, there is a lack of real-world measurements for cold starts. This study measured the emissions of 37 vehicles during idling cold starts, hot-stabilized trips, and driving cold starts. It found that cold starts contribute substantially to total exhaust mass emissions, and driver decisions regarding driving versus idling can significantly affect the contribution of cold starts, especially for CO and NOx.
Article
Environmental Sciences
Xianbao Shen, Yue Shi, Lei Kong, Xinyue Cao, Xin Li, Bobo Wu, Xiaolong Yao, Zhiliang Yao
Summary: This study conducted on-road measurement of Particle Number emissions from 18 China-3, China-4, and China-5 light-duty gasoline vehicles in Beijing, highlighting the significant decrease in PN emission factors of PFI vehicles under stricter standards and the higher PN EFs of GDI vehicles compared to PFI vehicles. The study also found variations in PN EFs under different driving conditions, as well as the impact of dilution ratio on test results, suggesting the need for further research to minimize test deviation.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Environmental Sciences
Xu Guan, Naiyue Zhang, Pengfei Tian, Chenguang Tang, Zhida Zhang, Ligong Wang, Yunshu Zhang, Min Zhang, Yumin Guo, Tao Du, Xianjie Cao, Jiening Liang, Lei Zhang
Summary: The vertical distribution of atmospheric aerosols, especially black carbon (BC) and single scattering albedo (SSA), in a semi-arid region of Northwest China in December 2018 was investigated using tethered balloon platform. It was found that BC profiles were influenced by local emissions, regional transport, ABL evolution, and topography, while SSA distribution was modulated by BC profiles. Diurnal variations showed that BC decreased and SSA increased in the ABL during daytime, but increased BC and decreased SSA at night.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Ran Tu, Junshi Xu, An Wang, Mingqian Zhang, Zhiqiang Zhai, Marianne Hatzopoulou
Summary: The study found that acceleration state tends to generate the highest emissions and fuel consumption, with HEV producing four times more CO emissions than some ICEVs. Toronto-specific drive cycles have difficulty meeting labeled fuel efficiency values, and HEV's CO emissions may be higher than ICEVs but still average 42% lower than the emission limit.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Liqiang He, Yan You, Xuan Zheng, Shaojun Zhang, Zhenhua Li, Zikai Zhang, Ye Wu, Jiming Hao
Summary: The study showed that diesel vehicles were the highest pollutant emitters due to intentional removal of aftertreatment systems. Under real-world conditions, hybrid electric vehicles (HEVs) could achieve approximately 30% carbon-reduction benefits compared to traditional gasoline vehicles, but had no significant improvements in tailpipe pollutant emissions besides NOX.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Maryam Zare Shahne, Mohammad Arhami, Vahid Hosseini, Imad El Haddad
Summary: This study focused on the fine particulate matter emitted from road traffic in Tehran, Iran. By collecting samples from various tunnel stations, the researchers were able to determine the source profile and emission factor of PM2.5 for light-duty vehicles in Tehran. Results showed similarity in vehicle fleets source profile with other countries and extracted an emission factor for PM2.5, which can be used for emission inventories improvement and management strategies in Tehran and other countries with similar traffic situations.
ENVIRONMENTAL POLLUTION
(2022)
Article
Environmental Sciences
Tak W. Chan, Jill Hendren, Rasto Brezny, Garry C. Gunter, David Lax, Joseph Kubsh
Summary: This study evaluated the effectiveness of two passive regenerating gasoline particulate filters in reducing gaseous and particle phase pollutants from gasoline direct inject vehicles. The study demonstrated the ability of the filters to mitigate pollutants during severe filter regeneration. The significance of this study lies in its findings about the filters' performance during aggressive drive cycle testing.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Computer Science, Information Systems
Yuvaraj Natarajan, Gitanjali Wadhwa, K. R. Sri Preethaa, Anand Paul
Summary: Accurate estimation of fuel consumption and emissions is crucial for assessing the impact of materials and emission control techniques on climate change in the transportation industry. The government of Canada has collected a large dataset on light-duty vehicles to reduce CO2 emissions by 40-45% by 2030. Researchers have developed regression models, including boosting algorithms, to predict CO2 emissions and provide insights for vehicle users and manufacturers. The proposed technique, Catboost, performs data processing efficiently and offers valuable recommendations.
Article
Engineering, Chemical
Yue Lin, Roya Bahreini, Seung-Bok Lee, Gwi-Nam Bae, Heejung Jung
AEROSOL SCIENCE AND TECHNOLOGY
(2020)
Article
Meteorology & Atmospheric Sciences
David R. Weise, Javier Palarea-Albaladejo, Timothy J. Johnson, Heejung Jung
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2020)
Article
Engineering, Environmental
David R. Weise, Heejung Jung, Javier Palarea-Albaladejo, David R. Cocker
JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION
(2020)
Article
Engineering, Environmental
Chas Frederickson, J. Wayne Miller, Heejung Jung
Summary: This study emphasizes the importance of measuring real-world activity and emissions to accurately quantify emission contributions in an emission inventory. Comparing real-world activity data with historical values found in certification cycle, it was found that the certification cycle activity values did not reflect the actual activity of harbor craft vessels.
JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION
(2022)
Article
Chemistry, Multidisciplinary
Brian Hwang, Ting Fang, Randy Pham, Jinlai Wei, Steven Gronstal, Brenda Lopez, Chas Frederickson, Tommaso Galeazzo, Xiaoliang Wang, Heejung Jung, Manabu Shiraiwa
Summary: In urban settings, vehicle emissions contribute significantly to the presence of PM2.5, containing environmentally persistent free radicals (EPFRs) that influence the generation of reactive oxygen species (ROS) in water. These EPFRs correlate with vehicular exhaust components and may be stabilized by metals emitted from tire and brake wear. Additionally, PM2.5 in urban areas generates OH and organic radicals in the aqueous phase, with EPFRs playing a role in OH radical production, while the oxidative potential of PM2.5 is linked to ROS formation and redox activity.
ACS EARTH AND SPACE CHEMISTRY
(2021)
Article
Environmental Sciences
Chengguo Li, Jacob Swanson, Liem Pham, Shaohua Hu, Shishan Hu, Gary Mikailian, Heejung S. Jung
Summary: Hybrid electric vehicle (HEV) technology is crucial in reducing the impact of internal combustion engines on air pollution and greenhouse gases. Despite HEVs having advantages such as lower cost and higher driving range, they still emit air pollutants. By studying emissions from different conditions of two vehicles, new insights can be gained.
ENVIRONMENTAL POLLUTION
(2021)
Article
Engineering, Environmental
Chas Frederickson, Heejung S. Jung, Wei Liu, Trevor S. Krasowsky, Mark Villela, Haiko Rading, Stefan Mussotter, David C. Quiros
Summary: This study measured in-use particulate matter and gaseous emissions on ferries, finding that real-world emissions were below certification limits. The importance of properly maintaining and operating selective catalytic reduction systems was underscored.
EMISSION CONTROL SCIENCE AND TECHNOLOGY
(2022)
Article
Engineering, Environmental
Brenda Lopez, Kent Johnson, Heejung Jung
Summary: Decades of regulations have reduced tailpipe PM emissions, but non-tailpipe PM emissions are not regulated and are expected to become a significant source of traffic-related PM emissions. This study aims to establish a test method and analysis for measuring brake activity of heavy-duty vehicles. The results provide critical information for accurately estimating emission inventory.
JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION
(2023)
Article
Engineering, Environmental
Boxin Zhang, Indu Aravind, Sisi Yang, Sizhe Weng, Bofan Zhao, Grace Johnson, Lucas Brown, Jason Olfert, Heejung Jung, Stephen B. Cronin
Summary: This study evaluates the beneficial effects of discharging nanosecond pulse transient plasma (NPTP) in a coaxial electrostatic precipitator for capturing nanoscale soot particles (similar to 50 nm) produced by an ethylene flame. The results show that NPTP can significantly enhance the removal efficiency of soot particles at lower DC voltages.
ENVIRONMENTAL SCIENCE-ADVANCES
(2023)
Article
Chemistry, Analytical
David Mendez-Jimenez, Pascale S. J. Lakey, Grace Johnson, Manabu Shiraiwa, Heejung Jung
Summary: This paper investigates the effects of ionizers on ozone concentration inside vehicle cabins and validates the findings through measurements and modeling. The study found that the use of ionizers increases in-cabin ozone concentration, but the specific effects depend on the type of ionizer and the ventilation of the vehicle.
ENVIRONMENTAL SCIENCE-PROCESSES & IMPACTS
(2022)
Article
Engineering, Environmental
Heejung Jung, David Quiros, Yang Li, Shaohua Hu, Yue Lin
Summary: Measurement methods for vehicle-emitted particulate matter (PM) have evolved with stricter emission standards, requiring evaluation of alternative methods. The diffusion charger showed responsiveness to a wide range of particle sizes and concentrations, indicating potential for identifying emission control system failures at lower concentrations.
EMISSION CONTROL SCIENCE AND TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Heejung Jung
WORLD ELECTRIC VEHICLE JOURNAL
(2020)
Article
Engineering, Environmental
Jiacheng Yang, Liem Pham, Kent C. Johnson, Thomas D. Durbin, Georgios Karavalakis, David Kittelson, Heejung Jung
EMISSION CONTROL SCIENCE AND TECHNOLOGY
(2020)
Article
Transportation Science & Technology
Herve Borrel, Paolo Taddonio, Heejung Jung
Summary: The study evaluates in-cabin pollution reduction using flap open/close strategies based on real-time air quality map information received by vehicles. Results show that the in-cabin pollution reduction achieved with flap control is significant, and it is expected that the efficiency of the method will increase as the data collected to create maps increases.
SAE INTERNATIONAL JOURNAL OF COMMERCIAL VEHICLES
(2022)
Article
Chemistry, Analytical
David Mendez-Jimenez, Pascale S. J. Lakey, Manabu Shiraiwa, Heejung Jung
Summary: Drivers and passengers are exposed to high concentrations of air pollutants while driving. Little is known about the behavior of individual gas pollutants in vehicle cabins. The study found that CO and NO concentrations increased while O-3 and NO2 concentrations decreased rapidly in recirculated cabin air. A kinetic model with 20 chemical reactions predicted the results well. Auto manufacturers are encouraged to develop control algorithms and devices to reduce passenger exposure to gaseous pollutants.
ENVIRONMENTAL SCIENCE-PROCESSES & IMPACTS
(2021)
Article
Engineering, Chemical
Francisco J. Higuera, Juan Fernandez de la Mora
Summary: This study investigates a particle condensation device that uses cold and warm humid air streams to achieve water vapor condensation. Compared to existing water condensation particle counters, this configuration offers advantages such as variable saturation ratio, accelerated penetration of water vapor, and a relatively uniform saturation field.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Brijal Prajapati, Vishal Dharaiya, Manoranjan Sahu, Chandra Venkatraman, Pratim Biswas, Kajal Yadav, Delwin Pullokaran, Ramya Sunder Raman, Ruqia Bhat, Tanveer Ahmad Najar, Arshid Jehangir
Summary: This study evaluated the performance of a low-cost particulate matter sensor and proposed a physics-based calibration method. The results showed that the physics-based calibration approach performed better compared to statistical models at both observation sites.
JOURNAL OF AEROSOL SCIENCE
(2024)
Correction
Engineering, Chemical
N. Searle, K. Kaur, K. Kelly
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Tianyu Cen, Laura Torrent, Andrea Testino, Christian Ludwig
Summary: In this study, a hyphenated setup consisting of a rotating disk diluter (RDD) with spICP-MS (RDDspICP-MS) was used for online sampling and characterization of metallic nanoparticles (NPs) in ambient pressure aerosols. The RDD allowed for constant flow rate sampling of aerosols and adjusting the dilution ratio for different particle number concentrations (PNCs). The feasibility of this setup was tested with different sizes of AuNPs in argon-based and air-based aerosols, and the results showed a lower limit of detection for number concentration. The capability of the setup to accurately investigate multi-modal samples and the interference of ionic species was also demonstrated.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
A. Valenzuela, E. Bazo, R. A. Rica, L. Alados-Arboledas, F. J. Olmo-Reyes
Summary: This article introduces a method to measure the extinction cross section of levitated particles using an electrodynamic trap and double-cavity ring down spectroscopy technique, and demonstrates the potential of this method in 1,2,6-hexanetriol particles through simulations and experiments. Unlike traditional methods, this technique provides crucial information about the extinction cross section of sodium chloride particles during dehydration and hydration processes.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Shadi Yaqoubi, Mohaddese Sokuti, Sahand Mazloum-Ravasan, Kofi Asare-Addo, Hamed Hamishehkar, Ali Nokhodchi
Summary: In this study, a modified version of ultrasonic spray pyrolysis was used to prepare salbutamol sulfate dry powder. The engineered particles showed suitable characteristics for effective drug delivery to the lungs and demonstrated acceptable aerosolization performance. This newly introduced method appears to be capable of producing dry powder formulations of different drugs without the need for surfactants or stabilizers.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Ashley L. Nord, Patrice Dosset, Pierre Slangen, Manouk Abkarian
Summary: Phonation has been found to be a potent transmission route for the COVID-19 virus. To control transmission, it is important to measure the amount of aerosols produced by speech. Researchers used digital in-line holography to overcome experimental challenges and successfully imaged the formation and deformation of saliva filaments in the mouth during speech, as well as the resulting aerosolized droplets.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Yating Wang, Yiyang Zhang, Zhu Fang, Xinxin Wu
Summary: The research investigates the energy dissipation in particle-wall collision with roughness using the finite element method. The results show that the presence of surface roughness leads to lower viscoelastic dissipation and higher restitution coefficient compared to a smooth surface. The collision time is identified as a key factor in predicting the energy dissipation.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Shaamrit Balendra, Akshay Kale, Julie Pongetti, Mohsen Kazemimanesh, Molly Haugen, Lee Weller, Adam Boies
Summary: The measurement of airborne particles is important for detecting and characterising air pollution, emissions, fire detection, occupational and climate impacts. However, current optical particle counters (OPCs) cannot measure ultrafine particles. This study explores the limitations of miniaturising a condensation particle counter (CPC) growth chamber and provides a toolkit for optimising the design of miniaturised CPC-GCs.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Markus Snellman, Namsoon Eom, Maria E. Messing, Knut Deppert, Chris Hogan
Summary: Segregated bimetallic nanoparticles, such as core-shell nanoparticles, have attracted widespread interest in various fields like biomedicine, catalysis, and optoelectronics. Aerosol technology provides an optimal platform for controlling the size, structure, and composition of nanoparticles, which are crucial parameters for tuning the material performance for specific applications. In this study, researchers developed a novel evaporator design that allows on-line coating of core particles with a shell directly in the gas phase. By utilizing a local heater, the researchers were able to decouple the heating process of the evaporating material from the aerosol particles, thereby limiting core-shell alloying. The resulting core-shell particle formation with controllable shell thickness was demonstrated using evaporation of zinc onto core particles of gold, tin, and bismuth. Simple models were also discussed to explain the observed growth process inside the evaporator and the formation of the shell.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Kentaro Misawa, Yuto Kasai
Summary: In this study, the laser-induced fluorescence technique was used to observe scattered and fluorescent signals from fluorescent polystyrene latex particles. The ratio of fluorescence to scattered signal intensities was found to be almost equal for particles of the same size, allowing for the separate observation of mixed-size fluorescent particles. Relative fluorescence intensities were obtained by incorporating ratios of fluorescence to scattered signal and relative scattered signal intensities.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Sripriya Nannu Shankar, William B. Vass, John A. Lednicky, Tracey Logan, Rebeccah L. Messcher, Arantzazu Eiguren-Fernandez, Stavros Amanatidis, Tara Sabo-Attwood, Chang-Yu Wu
Summary: This study introduces a testing system that allows for direct exposure of aerosolized viruses onto host cells. By collecting particles of different sizes and analyzing them, researchers obtained information on the concentration and viability of the virus at different particle sizes.
JOURNAL OF AEROSOL SCIENCE
(2024)
