The natural gas vehicle market is rapidly developing throughout the world, and the majority of such vehicles operate on compressed natural gas (CNG). However, most studies on the emission characteristics of CNG vehicles rely on laboratory chassis dynamometer measurements, which do not accurately represent actual road driving conditions. To further investigate the emission characteristics of CNG vehicles, two CNG city buses and two CNG coaches were tested on public urban roads and highway sections. Our results show that when speeds of 0-10km/hr were increased to 10-20km/hr, the CO, CO, nitrogen oxide (NO), and total hydrocarbon (THC) emission factors decreased by (71.6±4.3)%, (65.6±9.5)%, (64.9±9.2)% and (67.8±0.3)%, respectively. In this study, The Beijing city buses with stricter emission standards (Euro IV) did not have lower emission factors than the Chongqing coaches with Euro II emission standards. Both the higher emission factors at 0-10km/hr speeds and the higher percentage of driving in the low-speed regime during the entire road cycle may have contributed to the higher CO and CO emission factors of these city buses. Additionally, compared with the emission factors produced in the urban road tests, the CO emission factors of the CNG buses in highway tests decreased the most (by 83.2%), followed by the THC emission factors, which decreased by 67.1%.
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http://dx.doi.org/10.1016/j.jes.2016.01.028 | DOI Listing |
Chem Asian J
January 2025
JNCASR: Jawaharlal Nehru Centre for Advanced Scientific Research, New Chemistry Unit, Jakkur, 560064, Bangalore, INDIA.
This study investigates the photophysical behaviour of Mn/Fe and Mn/Sn co-doped CsPbCl3 perovskite nanocrystals (NCs) to explore carrier dynamics and dopant interactions. Using gated photoluminescence (PL) and temperature-dependent measurements, we elucidate the impact of dopant chemistry on exciton behaviour, focusing on vibrationally assisted delayed fluorescence (VADF) and energy transfer mechanisms. The efficiency of VADF is influenced by factors such as the bandgap, temperature, quantum confinement, and host composition.
View Article and Find Full Text PDFMethodsX
June 2025
Biofuel and Renewable Energy Research Center, Department of Chemical Engineering, Babol Noshirvani University of Technology, Babol, Iran.
Microbial fuel cells (MFCs) have garnered significant attention from researchers as an innovative and environmentally friendly method for the treatment of urban and industrial wastewater. The type and material of the electrode are critical factors affecting the efficiency and energy production of this process. The electrodeposition method was employed to dope nickel (Ni) and modify the surface of graphite plates (GP) and carbon felt (CF).
View Article and Find Full Text PDFTransl Lung Cancer Res
December 2024
School of Medicine, Southeast University, Nanjing, China.
Background: Resistance to chemoimmunotherapy in patients with advanced non-small cell lung cancer (NSCLC) necessitates effective prognostic biomarkers. Although F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) has shown potential for efficacy assessment, it has been mainly evaluated in immuno-monotherapy setting, lacking elaborations in the scenarios of immunotherapy combined with chemotherapy. To tackle this dilemma, we aimed to build a non-invasive PET/CT-based model for stratifying tumor heterogeneity and predicting survival in advanced NSCLC patients undergoing chemoimmunotherapy.
View Article and Find Full Text PDFJ Phys Chem A
January 2025
Centro de Bioinformática, Simulación y Modelado (CBSM), Departamento de Bioinformática, Facultad de Ingeniería, Universidad de Talca, Talca 3465548, Chile.
In this research, we investigated the essential role of biogenic volatile organic compound emissions in regulating tropospheric ozone levels, atmospheric chemistry, and climate dynamics. We explored linalool ozonolysis and secondary organic aerosol formation mechanisms, providing key insights into atmospheric processes. Computational techniques, such as density functional theory calculations and molecular dynamics simulations, were employed for the analysis.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
School for Environment and Sustainability, University of Michigan, Ann Arbor, Michigan 48109, United States.
The use of transportation network companies (TNCs), such as Uber and Lyft, is widespread in many US cities, including those with good transit. However, transit use produces smaller externalities relative to private vehicles and is cheaper but can increase travel time. Here we compare the benefits and costs of real TNC trips in Chicago to a counterfactual in which they are performed by transit.
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