Exploring the HONO source during the COVID-19 pandemic in a megacity in China.

HONO is a critical precursor of •OH, but its sources are controversial due to its complex formation mechanism. This study conducted comprehensive observations in Zhengzhou from April 26 to May 11, 2022. Low NO concentrations were observed during the Covid epidemic period (EP) (10.

Establishment and verification of anthropogenic speciated VOCs emission inventory of Central China.

Improving the accuracy of anthropogenic volatile organic compounds (VOCs) emission inventory is crucial for reducing atmospheric pollution and formulating control policy of air pollution. In this study, an anthropogenic speciated VOCs emission inventory was established for Central China represented by Henan Province at a 3 km × 3 km spatial resolution based on the emission factor method. The 2019 VOCs emission in Henan Province was 1003.

Pollution characteristics and prospective risk of microplastics in the Zhengzhou section of Yellow River, China.

The ubiquitous occurrence of microplastics (MPs) in the freshwater has attracted widespread attention. The Zhengzhou section of the Yellow River was the most prosperous region in ancient China, and the rapid urbanization, industrialization, and agricultural practices contributed to MPs pollution in aquatic systems recently, whereas the contamination status of MPs in the area is still not available. In this study, a total of fourteen sampling cross-sections were selected in the region to collect water samples systematically for the analysis of MPs pollution characteristics and potential risks.

[Occurrence Characteristic and Risk Assessment of Microplastics in Sishui River (Xingyang Section)].

Urban rivers are the main receptors and transporters of microplastic pollution. Understanding the occurrence and environmental risk of microplastics in urban rivers can provide theoretical basis for further control of microplastic pollution. The Sishui River, a tributary of the Yellow River, was selected as the research object.

[Characteristics of Secondary Inorganic Ions in PM and Its Influencing Factors in Summer in Zhengzhou].

Nitrate (NO), sulfate (SO), and ammonium (NH) are important components of PM, and studying their characteristics and influencing factors is essential for the continuous improvement of air quality. A series of online instruments were used to analyze the chemical components of PM in Zhengzhou in the summer of 2020. The results showed that the average (PM) was (28 ±13) μg·m, showing a daily variation characteristic of high at night and low during the day.

Characteristics and source apportionment of ambient volatile organic compounds and ozone generation sensitivity in urban Jiaozuo, China.

In recent years, many cities have taken measures to reduce volatile organic compounds (VOCs), an important precursor of ozone (O), to alleviate O pollution in China. 116 VOC species were measured by online and offline methods in the urban area of Jiaozuo from May to October in 2021 to analyze the compositional characteristics. VOC sources were analyzed by a positive matrix factorization (PMF) model, and the sensitivity of ozone generation was determined by ozone isopleth plotting research (OZIPR) simulation.

Formation pathway of secondary inorganic aerosol and its influencing factors in Northern China: Comparison between urban and rural sites.

Secondary inorganic aerosol, including sulfate, nitrate, and ammonium (SNA), is a significant source of PM during haze episodes in Northern China. A series of high-time-resolution instruments were used in collecting PM chemical components and gaseous pollutants during a regional heavy pollution process from January 12-25, 2018, at urban and rural sites. SNA, accounting for >50% of PM at both sites, had greater importance on haze formation.

[Pollution Characterization, Source Identification, and Health Risks of Atmospheric Particle-Bound Heavy Metals in PM in Zhengzhou City: Based on High-resolution Data].

In order to study the pollution characteristics and sources of heavy metals in urban atmospheric PM, 21 elements in atmospheric PM in Zhengzhou City were detected using an online metal analyzer during July and October 2017 and January and April 2018, and the changes in heavy metal concentrations were analyzed. Heavy metals were traced by enrichment factors, principal component analysis, and potential source function. The US EPA risk assessment model was used to assess their health risks.

[Vehicle Air Pollutant Emission Inventory and Characterization in Henan Province from 2016 to 2019].

Based on the collected urban motor vehicle activity ownership and traffic flow of highways, combined with the mileage and source profiles of VOCs, using the emission factor method, we established high-resolution emission inventories from 2016 to 2019 for urban and 2016-based highway motor vehicles, respectively, in Henan Province, China. The results showed that gasoline vehicles, particularly minibuses and ordinary motorcycles, were the main contributors of CO, VOCs, and NH, whereas heavy-duty and light-duty diesel trucks emitted SO, NO, and PM. Vehicles with China 1, China 3, and China 4 emission standards contributed significantly to pollutant emissions in the fleet.

[Characteristics, Meteorological Influences, and Transport Source of Ozone Pollution in Zhengzhou City].

Based on online monitoring data of air quality and meteorological parameters, the long-term variations, spatial differences, and meteorological influencing factors of ground-level ozone (O) pollution in Zhengzhou were studied. In addition, the transport pathways and potential source regions of O were investigated. The results show that surface O concentrations at the city station in Zhengzhou City increased significantly during the period 2014-2018 (<0.