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Sociolinguistics research based on Chinese reality
In: International journal of the sociology of language: IJSL, Band 1990, Heft 81, S. 21-42
ISSN: 1613-3668
Liang an jiao liu yu she hui fa zhan: " xiao san tong " yu lu you yan jiu wen ji
In: She hui ke xue lei AF0109
In: 社會科學類 AF0109
Molecular Characteristics of Ambient Organic Aerosols in Shanghai Winters Before and after the COVID-19 Outbreak
In: STOTEN-D-22-22413
SSRN
The study of lead content distribution in Chinese seafood and its oral bioavailability in mice
In: Environmental science and pollution research: ESPR, Band 23, Heft 2, S. 1714-1721
ISSN: 1614-7499
Microstructure and tribological properties of Ti–Cu intermetallic compound coating
In: Materials & Design (1980-2015), Band 36, S. 482-489
The Light Absorbing and Molecule Characteristic of Pm2.5 Brown Carbon Observed in Urban Shanghai
In: ENVPOL-D-22-07228
SSRN
A method for particulate matter 2.5 (PM2.5) biotoxicity assay using luminescent bacterium
In: Ecotoxicology and environmental safety: EES ; official journal of the International Society of Ecotoxicology and Environmental safety, Band 170, S. 796-803
ISSN: 1090-2414
Environmental lead pollution threatens the children living in the Pearl River Delta region, China
In: Environmental science and pollution research: ESPR, Band 19, Heft 8, S. 3268-3275
ISSN: 1614-7499
Characteristics of non-methane hydrocarbons emitted from Chinese kitchens and their effect on ozone formation potential
In: Air quality, atmosphere and health: an international journal, Band 16, Heft 3, S. 583-593
ISSN: 1873-9326
Size-Fractionated Ultrafine Particles and Their Optical Properties Produced from Heating Edible Oils in a Kitchen Laboratory
In: STOTEN-D-22-09465
SSRN
Attributing Increases in Ozone to Accelerated Oxidation of Volatile Organic Compounds at Reduced Nitrogen Oxides Concentrations
In: PNAS nexus, Band 1, Heft 5
ISSN: 2752-6542
AbstractSurface ozone (O3) is an important secondary pollutant affecting climate change and air quality in the atmosphere. Observations during the COVID-19 lockdown in urban China show that the co-abatement of nitrogen oxides (NOx) and volatile organic compounds (VOCs) caused winter ground-level O3 increases, but the chemical mechanisms involved are unclear. Here we report field observations in the Shanghai lockdown that reveals increasing photochemical formation of O3 from VOC oxidation with decreasing NOx. Analyses of the VOC profiles and NO/NO2 indicate that the O3 increases by the NOx reduction counteracted the O3 decreases through the VOC emission reduction in the VOC-limited region, and this may have been the main mechanism for this net O3 increase. The mechanism may have involved accelerated OH–HO2–RO2 radical cycling. The NOx reductions for increasing O3 production could explain why O3 increased from 2014 to 2020 in response to NOx emission reduction even as VOC emissions have essentially remained unchanged. Model simulations suggest that aggressive VOC abatement, particularly for alkenes and aromatics, should help reverse the long-term O3 increase under current NOx abatement conditions.
Characterization of Non-Methane Total Hydrocarbons (Nmhcs) and Their Ozone Formation Potential for Indoor Cooking Emissions
In: CHEM97167
SSRN
Modeled changes in source contributions of particulate matter during the COVID-19 pandemic in the Yangtze River Delta, China
Within a short time after the outbreak of coronavirus disease 2019 (COVID-19) in Wuhan, Hubei, the Chinese government introduced a nationwide lockdown to prevent the spread of the pandemic. The quarantine measures have significantly decreased the anthropogenic activities, thus improving air quality. To study the impacts caused by the lockdown on specific source sectors and regions in the Yangtze River Delta (YRD), the Community Multiscale Air Quality (CMAQ) model was used to investigate the changes in source contributions to fine particulate matter (PM 2.5 ) from 23 January to 28 February 2020, based on different emission control cases. Compared to case 1 (without emission reductions), the total PM 2.5 mass for case 2 (with emission reductions) decreased by more than 20 % over the entire YRD, and the reduction ratios of its components were 15 %, 16 %, 20 %, 43 %, 34 %, and 35 % in primary organic aerosol (POA), elemental carbon (EC), sulfate, nitrate, ammonium, and secondary organic aerosol (SOA), respectively. The source apportionment results showed that PM 2.5 concentrations from transportation decreased by 40 %, while PM 2.5 concentrations from the residential and power sectors decreased by less than 10 % due to the lockdown. Although all sources decreased, the relative contribution changed differently. Contributions from the residential sector increased by more than 10 % to 35 %, while those in the industrial sector decreased by 33 %. Considering regional transport, the total PM 2.5 mass of all regions decreased 20 %–30 % in the YRD, with the largest decreased value of 5.0 µg m −3 in Henan, Hebei, Beijing, and Tianjin (Ha-BTH). In Shanghai, the lower contributions from local emissions and regional transmission (mainly Shandong and Ha-BTH) led to the reduced PM 2.5 . This study suggests adjustments of control measures for various sources and regions.
BASE
Changes in source contributions of particulate matter during COVID-19 pandemic in the Yangtze River Delta, China
Within a short time after the outbreak of coronavirus disease 2019 (COVID-19) in Wuhan, Hubei, the Chinese government took a nationwide lockdown to prevent the spread of the pandemic. The quarantine measures have significantly decreased the anthropogenic activities, and thus improving the air quality. To study the impacts caused by the lockdown on specific source sectors and regions in the Yangtze River Delta (YRD), the Community Multiscale Air Quality (CMAQ) model was used to investigate the changes in source contributions to fine particulate matter (PM 2.5 ) from January 23 to February 28, 2020, based on different emission control cases. Compared to Case 1 (without emission reductions), the total PM 2.5 mass for Case 2 (with emission reductions) decreased by larger than 20 % over the entire YRD and the reduction ratios of its components were 15 %, 16 %, 20 %, 43 %, 34 %, and 35 % in primary organic aerosol (POA), elemental carbon (EC), sulfate, nitrate, ammonium, and secondary organic aerosol (SOA), respectively. The source appointment results showed that PM 2.5 concentrations from transportation decreased by 40 % while from residential and power decreased by less than 10 % due to the lockdown. Although all sources decreased, the relative contribution changed differently. Contributions of residential increased by more than 10 % to 35 %, while that of the industry decreased to 33 %. Considering the regional transport, the total PM 2.5 mass of all regions decreased 20–30 % in the YRD with the largest decreased value of 5.0 μg m −3 in Henan, Hebei, Beijing, and Tianjin (Ha-BTH). In Shanghai, the lower contributions from local emissions and regional transmission (mainly Shandong and Ha-BTH) led to the reduced PM 2.5 . This study suggested adjustments of control measures for various sources and regions. Also, it was necessary to strengthen the regional collaboration at a large scale to improve the air quality in the YRD.
BASE