Publications by authors named "Yezheng Wu"

This study investigated the concentrations of atmospheric pollutants in the urban area of Suzhou from May to June, 2017-2021. The variation characteristics and annual changes of ozone (O), nitrogen oxide (NO), total oxidant (O), carbon monoxide (CO), and volatile organic compounds (VOCs) were analyzed. The O formation mechanism and its annual changes were studied using an Observation-Based Model (OBM), and VOCs source apportionments and their trends were discussed.

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To study the variation in concentration and source analysis of metal elements during COVID-19 control in Suzhou, a multi-metal online monitor was used to determine hourly online data of 14 metal elements from December 1, 2019 to March 31, 2020. This study analyzed variation in concentration and source analysis of metal elements using a PMF model before, during, and after shutdown during COVID-19 control. The results showed that the concentrations of Cr, Mn, Zn, and Fe during shutdown decreased the most, by 87.

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Here we present seasonal chemical characteristics, formations, sources of PM in the year 2020 in Suzhou, Yangtze River Delta, China. Expectedly, organic matter (OM) found to be the most dominant component of PM, with a year-average value of 10.3 ± 5.

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To control the spread of COVID-19, rigorous restrictions have been implemented in China, resulting in a great reduction in pollutant emissions. In this study, we evaluated the air quality in the Yangtze River Delta during the COVID-19 lockdown period using satellite and ground-based data, including particle matter (PM), trace gases, water-soluble ions (WSIs) and black carbon (BC). We found that the impacts of lockdown policy on air quality cannot be accurately assessed using MODIS aerosol optical depth (AOD) data, whereas the tropospheric nitrogen dioxide (NO) vertical column density can well reflect the influences of these restrictions on human activities.

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To control the spread of the 2019 novel coronavirus (COVID-19), China imposed rigorous restrictions, which resulted in great reductions in pollutant emissions. This study examines the characteristics of air pollutants, including PM (particles with aerodynamic diameters < 2.5 μm), gas pollutants, water-soluble ions (WSIs), black carbon (BC) and elements, as well as the source apportionment of PM in Suzhou before, during and after the Chinese New Year (CNY) holiday of 2020 (when China was under an unprecedented state of lockdown to restrict the COVID-19 outbreak).

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To explore the variation of mercury in the atmosphere in Suzhou, continuous monitoring of gaseous element mercury (GEM), gaseous oxidized mercury (GOM), and particulate bound mercury (PBM) was conducted from January 1 to December 31, 2018, in Suzhou. The weights trajectory analysis method (CWT) and concentration rose were used to analyze the atmospheric mercury sources and concentration variation. The results showed that during the monitoring period, the concentration ranges of GEM, GOM, and PBM in Suzhou were 0-53.

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