Constructing the 3D Spatial Distribution of the HCHO/NO Ratio via Satellite Observation and Machine Learning Model.

The satellite-based tropospheric column ratio of HCHO to NO (FNR) is widely used to diagnose ozone formation sensitivity; however, its representation of surface conditions remains controversial. In this study, an approach to construct the 3D spatial distribution of the FNR in the lower troposphere was proposed. Based on satellite and multiaxes-differential Optical Absorption Spectroscopy (MAX-DOAS) data, the horizontal and vertical distributions of the FNR have been respectively obtained.

Role of gas-particle conversion of ammonia in haze pollution under ammonia-rich environment in Northern China and prospects of effective emission reduction.

As an important precursor of secondary inorganic aerosols (SIAs), ammonia (NH) plays a key role in fine particulate matter (PM) formation. In order to investigate its impacts on haze formation in the North China Plain (NCP) during winter, NH concentrations were observed at a high-temporal resolution of 1 min by using the SP-DOAS in Tai'an from December 2021 to February 2022. During the observation period, the average NH concentration was 11.

Typhoon- and pollution-driven enhancement of reactive bromine in the mid-latitude marine boundary layer.

Tropospheric reactive bromine is important for atmospheric chemistry, regional air pollution, and global climate. Previous studies have reported measurements of atmospheric reactive bromine species in different environments, and proposed their main sources, e.g.

The impact of thickness-related grain boundary migration on hole concentration and mobility of p-type transparent conducting CuI films.

CuI films present promising optoelectronic properties for transparent conductors. However, the high hole concentration in CuI films hinders the controllable modulation of hole mobility, limiting their application in low-dimensional thin-film transistors. In this study, CuI films were prepared through a Cu film iodination method at room temperature, and a systematic investigation was conducted on the modulation of hole concentration and mobility with varying film thickness.

A new portable open-path instrument for ambient NH and on-road emission measurements.

Increased attentions to vehicle emission of NH have been paid since it is generally regarded as an important source in urban areas. Here, we developed a movable instrument based on Differential Optical Absorption Spectroscopy (DOAS) principle for detecting on-road NH, which can avoid the losses in the sampling process attributed to the non-sampling methods. For this mobile DOAS, the temporal resolution, detection limit and relative error for NH were 1 min, 2.

Vertical distributions of atmospheric HONO and the corresponding OH radical production by photolysis at the suburb area of Shanghai, China.

Nitrous acid (HONO) is considered as one of the main sources of the hydroxyl radical (OH), the most relevant oxidant in the atmosphere. Multi-AXis-Differential Optical Absorption Spectroscopy (MAX-DOAS) measurements were conducted to obtain the vertical profiles of aerosol and HONO from November 1, 2020 to January 31, 2021 at a suburb site of Shanghai, China. HONO was mainly distributed near the surface, but high values HONO occasionally occurred around 0.

Impact Assessment of COVID-19 Lockdown on Vertical Distributions of NO and HCHO From MAX-DOAS Observations and Machine Learning Models.

Responses to the COVID-19 pandemic led to major reductions on air pollutant emissions in modern history. To date, there has been no comprehensive assessment for the impact of lockdowns on the vertical distributions of nitrogen dioxide (NO) and formaldehyde (HCHO). Based on profiles from 0 to 2 km retrieved by Multi-AXis-Differential Optical Absorption Spectroscopy observation and a large volume of real-time data at a suburb site in Shanghai, China, four types of machine learning models were developed and compared, including multiple linear regression, support vector machine, bagged trees (BT), and artificial neural network.

Spatiotemporal characterization of aerosols and trace gases over the Yangtze River Delta region, China: impact of trans-boundary pollution and meteorology.

Background: The spatiotemporal variation of observed trace gases (NO, SO, O) and particulate matter (PM, PM) were investigated over cities of Yangtze River Delta (YRD) region including Nanjing, Hefei, Shanghai and Hangzhou. Furthermore, the characteristics of different pollution episodes, i.e.

Revegetation by sowing reduces soil bacterial and fungal diversity.

Aim: The aim of this study was to understand the effects of revegetation on the diversity of bacteria and fungi in soil by sowing a single species and exploring the underlying mechanism.

Location: Beijing, China.

Taxon: Plants and Microbes.