[Source Analysis of Ozone and Its Precursors in Zibo Based on 3-D Air Quality Model].

Based on the ISAM module in the WRF-CMAQ model, this study analyzed the source contribution(both regional and sectoral) of O and its precursors(NO and VOCs) in Zibo in June 2021. Days with a maximum daily 8-h average(MDA8) O higher(lower) than 160 μg·m were defined as polluted(clean) days. Differences in the source contribution between clean days and polluted days were compared, and a typical pollution period was selected for further process analysis.

[Characteristics of Soil NO Emissions in the Yangtze River Delta Region for Year 2018].

Soil NO emissions represent an important source of atmospheric nitric oxide (NO) and play an important role in atmospheric chemistry. Based on the latest BDSNP algorithm, this study estimated the soil NO emissions over the Yangtze River Delta region for the year 2018 and further analyzed the associated temporal and spatial variations and uncertainties. The results showed that the annual soil NO emissions in 2018 over the YRD region was 213.

[Role of Land Use Changes on Ammonia Emissions from Agricultural Ecosystems in the Yangtze River Delta Region from 2000 to 2018].

Based on Landsat satellite remote sensing images, this study interprets land use changes in the Yangtze River Delta (YRD) region from 2000 to 2018. Combined with changes in nitrogen fertilizer application, the changes in ammonia emissions from farmland ecosystem due changes in land use and nitrogen fertilizer application were further investigated. The results show that along with the rapid urbanization process, the area of cultivated land in the YRD region has gradually decreased from 276269 km (49% of total land area) in 2000 to 244001 km (44%) in 2018.

[Emission Inventory of Intermediate Volatility Organic Compounds(IVOCs) from Biomass Burning in the Yangtze River Delta During 2010-2018].

Intermediate volatility organic compounds (IVOCs) are important precursors of secondary organic aerosols (SOA) but are currently not included in the conventional emissions inventories. Biomass burning represents an important source of IVOCs that could contribute to SOA formation. This study estimated the IVOC emissions from biomass burning in the Yangtze River Delta (YRD) region from 2010 to 2018 based on the fire inventory from NCAR (FINN) and the IVOCs/primary organic aerosol (POA) ratio reported in literature.

[Regional Air Pollution Process in Winter over the Yangtze River Delta and Its Influence on Typical Northern Cities].

In this study, we analyzed several pollution episodes that occurred in the autumn and winter of 2018-2019 using multiple methods including the hierarchical clustering analysis, backward trajectory, and potential source contribution analysis based on monitored air quality and meteorological data. Bengbu, being a representative city to the north of the Yangtze River Delta (YRD) region and located in a heavily polluted area during these two pollution processes, is the focus of this work. The results indicated that the northern part of the YRD region is affected because of unfavorable meteorological conditions such as weak ground pressure, high humidity, low temperature, low wind speeds, and regional transport.

[Impact of Parameterization on the Estimation of Ammonia Emissions:A Case Study over the Yangtze River Delta].

Atmospheric ammonia plays an important role in the formation of secondary inorganic composition of PM, which has attracted a high level of attention from researchers both in China and abroad. Quantifying ammonia emissions is of great scientific significance regarding research on the formation of secondary aerosol, realizing better model performance, and control of ammonia emissions. Previous studies have shown that agricultural activities are the dominant source of atmospheric ammonia, of which livestock and poultry farming contribute the most.

[Emission Inventory of Intermediate Volatility Organic Compounds from Vehicles in the Yangtze River Delta in 2017 and the Impact on the Formation Potential of Secondary Organic Aerosols].

Intermediate volatility organic compounds (IVOCs) have a significant contribution to the formation of secondary organic aerosols (SOA) in the atmosphere, but are not included in the current emission inventory. In this study, IVOC emissions from vehicles are estimated for the Yangtze River Delta region (YRD) for 2017 based on two methods:the emission factor method and the IVOCs/POA scaling factor method. Uncertainties in the estimated IVOCs emissions and the impact on their potential formation are discussed.

[Ozone source apportionment at urban area during a typical photochemical pollution episode in the summer of 2013 in the Yangtze River Delta].

With the fast development of urbanization, industrialization and mobilization, the air pollutant emissions with photochemical reactivity become more obvious, causing a severe photochemical pollution with the characteristics of high ozone concentration. However, the ozone source identification is very complicated due to the high non linearity between ozone and its precursors. Thus, ways to reduce ozone is still not clear.

[Characteristics and influencing factors of carbonaceous aerosols in PM2.5 in Shanghai, China].

Organic carbon (OC) and elemental carbon (EC) in PM2.5 samples collected in urban (Xujiahui) and industrial (Baoshan) areas in Shanghai during 2007-2008 were analyzed with a DRI carbon analyzer using IMPROVE-TOR protocol. The results showed that the seasonal average concentrations of OC and EC were highest in the winter and lowest in the summer.

Development of a compound-specific carbon isotope analysis method for 2-methyltetrols, biomarkers for secondary organic aerosols from atmospheric isoprene.

The stable carbon isotope compositions of 2-methyltetrols, biomarker compounds for secondary organic aerosols formed from isoprene in the atmosphere, have been determined by gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS). In this work, isoprene with various delta(13)C values was used to produce 2-methyltetrols via an oxidation reaction with hydrogen peroxide in sulfuric acid under direct sunlight. The target compounds with different stable carbon isotope compositions were then derivatized by methylboronic acid with a known delta(13)C value and measured by GC/C/IRMS.