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Quantifying the impacts of emissions and meteorology on the interannual variations of air pollutants in major Chinese cities from 2015 to 2021

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Science China Earth Sciences 2023年第8期66卷 1725-1737页

作者： Qili Dai Tianjiao dai Linlu HOU Linxuan LI Xiaohui BI Yufen ZHANG Yinchang FENG State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control College of Environmental Science and EngineeringNankai UniversityTianjin 300350China China Meteorological Administration-Nankai University Cooperative Laboratory for Atmospheric Environment-Health Research Tianjin 300350China

Air pollutant concentration is a function of emission rates and meteorology.To accurately evaluate the effect of control measures,the meteorological covariate must be corrected from the observations.This study quantified the impacts of emission abatement and meteorological condition on the interannual variations of SO_(2),NO_(2),CO,O_(3),PM_(10) and PM_(2.5) concentrations in 31 major Chinese cities using an optimized machine learning-based meteorological normalization technique.Overall,the annual average concentrations of SO_(2),NO_(2),CO,PM_(10)and PM_(2.5)were reduced by 86%,51%,99%,86% and 88%from 2015 to 2020,respectively,in the studied cities,attributable to their emission reductions.However,the concentration of O_(3) was found with no significant decrease with the reduction of precursors.Emission abatement notably improved air quality between 2015 and 2018.Such a decline in emissions tended to progressively slow down since 2018.Overall,the meteorological conditions in 2016–2017 and 2018–2019 were unfavorable for a better air quality,while it became favorable in 2020–2021.Specifically,emission abatement in 2021 further lowered the concentrations of SO_(2),NO_(2),CO,and PM_(2.5),while the emission of PM_(10) increased.And changes in precursors emissions worsened O_(3) air quality.To meet the demand of improving air quality,more aggressive abatement measures need to be formulated to synergistically reduce NOx,volatile organic compounds,and coarse particles.

关键词： Air pollution Air quality Machine learning Meteorology Emissions Policy evaluation

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Impact of meteorological condition changes on air quality and particulate chemical composition during the COVID-19 lockdown

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Journal of Environmental Sciences 2021年第11期33卷 45-56页

作者： Jing Ding Qili Dai Yafei Li Suqin Han Yufen Zhang Yinchang Feng Tianjin Environmental Meteorological Center Tianjin 300074China State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control College of Environmental Science and EngineeringNankai UniversityTianjin 300350China CMA-NKU Cooperative Laboratory for Atmospheric Environment-Health Research Tianjin 300074China

Stringent quarantine measures during the Coronavirus Disease 2019(COVID-19)lockdown period(January 23,2020 to March 15,2020)have resulted in a distinct decrease in anthropogenic source emissions in North China Plain compared to the paralleled period of 2019.Particularly,22.7%decrease in NO_(2)and 3.0%increase of O_(3)was observed in Tianjin,nonlinear relationship between O_(3)generation and NO_(2)implied that synergetic control of NOx and VOCs is needed.Deteriorating meteorological condition during the COVID-19 lockdown obscured the actual PM2.5 reduction.Fireworks transport in 2020 Spring Festival(SF)triggered regional haze pollution.PM2.5 during the COVID-19 lockdown only reduced by 5.6%in Tianjin.Here we used the dispersion coefficient to normalize the measured PM2.5(DN-PM2.5),aiming to eliminate the adverse meteorological impact and roughly estimate the actual PM2.5 reduction,which reduced by 17.7%during the COVID-19 lockdown.In terms of PM2.5 chemical composition,significant NO_(3)−increase was observed during the COVID-19 lockdown.However,as a tracer of atmospheric oxidation capacity,odd oxygen(Ox=NO_(2)+O_(3))was observed to reduce during the COVID-19 lockdown,whereas relative humidity(RH),specific humidity and aerosol liquid water content(ALWC)were observed with noticeable enhancement.Nitrogen oxidation rate(NOR)was observed to increase at higher specific humidity and ALWC,especially in the haze episode occurred during 2020SF,high air humidity and obvious nitrate generation was observed.Anomalously enhanced air humidity may response for the nitrate increase during the COVID-19 lockdown period.

关键词： COVID-19 lockdown Air quality Meteorological condition Air humidity Aerosol chemistry

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Size distribution and chemical characteristics of particles from crop residue open burning in North China

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Journal of Environmental Sciences 2021年第11期33卷 66-76页

作者： Tingkun Li Qili Dai Xiaohui Bi Jianhui Wu Yufen Zhang Yinchang Feng State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control College of Environmental Science and EngineeringNankai UniversityTianjin300350China.

Crop residue open burning is an important emission source of ambient particles in China.This study analyzed the particle emission characteristics of crop residue open burning through combustion experiments with a novel open combustion simulation device using three typical crop straws in north China(corn,wheat,and rice).Particle samples size ranging from 0.006–9.890μm were collected by an Electrical Low Pressure Impactor plus,a high size-resolution instrument capable of dividing particles into 14 size stages.The size distributions of organic carbon(OC),elemental carbon(EC),water-soluble ions,and elements were analyzed,and source chemical profiles were constructed for PM0.1,PM1,PM2.5,and PM10.The number concentration of particles was concentrated in the Aiken nuclei mode(0.006–0.054μm),accounting for 75%of the total number,whereas the mass concentration was concentrated in the accumulation mode(0.054–0.949μm),accounting for 85.43%of the mass loading.OC,EC,Cl−,and K(include total K and water-soluble K)were the major chemical components of the particles,whose mass percentage distributions differed from those of other components.These fivemain components exhibited a bell-shaped size distribution in the 0.006–9.890μm range,whereas the other components exhibited a U-shaped distribution.Among the chemical profiles for PM0.1–PM10,OC was the most important component at 10–30%,followed by EC at 2%–8%.The proportions of K^(+),Cl^(−),and K varied substantially in different experimental groups,ranging from 0–15%,and K+and Cl−were significantly correlated(r=0.878,α=0.000).

关键词： Crop residue Open burning Size distribution Source profile Electrical Low Pressure Impactor plus(ELPI+)

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Impacts of meteorology and precursor emission change on O_(3) variation in Tianjin, China from 2015 to 2021

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Journal of Environmental Sciences 2023年第4期126卷 506-516页

作者： Jing Ding Qili Dai Wenyan Fan Miaomiao Lu Yufen Zhang Suqin Han Yinchang Feng Tianjin Environmental Meteorological Center Qi xiangtai roadTianjin 300074China State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control College of Environmental Science and EngineeringNankai UniversityTianjin 300350China CMA-NKU Cooperative Laboratory for Atmospheric Environment-Health Research Tianjin 300074China

Deterioration of surface ozone (O_(3)) pollution in Northern China over the past few years received much attention.For many cities,it is still under debate whether the trend of surface O_(3)variation is driven by meteorology or the change in precursors emissions.In this work,a time series decomposition method (Seasonal-Trend decomposition procedure based on Loess (STL)) and random forest (RF) algorithm were utilized to quantify the meteorological impacts on the recorded O_(3)trend and identify the key meteorological factors affecting O_(3)pollution in Tianjin,the biggest coastal port city in Northern China.After “removing” the meteorological fluctuations from the observed O_(3)time series,we found that variation of O_(3)in Tianjin was largely driven by the changes in precursors emissions.The meteorology was unfavorable for O_(3)pollution in period of 2015-2016,and turned out to be favorable during 2017-2021.Specifically,meteorology contributed 9.3μg/m^(3)O_(3)(13%) in 2019,together with the increase in precursors emissions,making 2019 to be the worst year of O_(3)pollution since 2015.Since then,the favorable effects of meteorology on O_(3)pollution tended to be weaker.Temperature was the most important factor affecting O_(3)level,followed by air humidity in O_(3)pollution season.In the midday of summer days,O_(3)pollution frequently exceeded the standard level (>160μg/m^(3)) at a combined condition with relative humidity in 40%-50%and temperature>31℃.Both the temperature and the dryness of the atmosphere need to be subtly considered for summer O_(3)forecasting.

关键词： Ozone Meteorological conditions Time series decomposition Random forest Meteorological adjustment

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Insight into the critical factors determining the particle number concentrations during summer at a megacity in China

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Journal of Environmental Sciences 2019年第1期31卷 169-180页

作者： Baoshuang Liu Xiaohui Bi Jiaying Zhang Jie Yuan Zhimei Xiao Qili Dai Yinchang Feng Yufen Zhang State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control & Center for Urban Transport Emission Research College of Environmental Science and EngineeringNankai University Tianjin Environmental Monitoring Center

To identify the critical factors impacting the number concentration of particles with the aerodynamic diameters less than 2.5 μm(PNC_(2.5)), the continuous measurement of PNC_(2.5),chemical components in PM_(2.5), gaseous pollutants and meteorological conditions were conducted at an urban site in Tianjin in June 2015. Results indicated that the average PNC_(2.5) was 2839 ± 2430 d N/dlog Dp 1/cm^3 during the campaign. Compared to other meteorological parameters, the relative humidity(RH) had the strongest relationship with PNC_(2.5), with a Pearson's correlation coefficient of 0.53, and RH larger than 30% influenced strongly PNC_(2.5).The important influence of secondary reactions on PNC_(2.5) was inferred due to higher correlation coefficients between PNC_(2.5) and SO_4^(2-), NO_3^-, NH_4^+(r = 0.78–0.89; p < 0.01) and between PNC_(2.5) and ratios that represent the conversion of nitrogen and sulfur oxides to particulate matter(r = 0.42–0.49; p < 0.01). Under specific RH conditions, there were even stronger correlations between PNC_(2.5) and NO_3^-, SO_4^(2-), NH_4^+, while those between PNC_(2.5) and EC, OC were relatively weak, especially when RH exceeded 50%. Principal component analysis(PCA) and Pearson's correlation analysis indicated that secondary sources, vehicle emission and coal combustion might be major contributors to PNC_(2.5). Backward trajectory and potential source contribution function(PSCF) analysis suggested that the transport of air masses originated from these regions around Tianjin(Liaoning, Hebei, Shandong and Jiangsu) influenced critically PNC_(2.5). The north of Jiangsu, the west of Shandong, and the east of Hebei were distinguished as major potential source-areas of PNC_(2.5) by PSCF model.

关键词： Particle number concentration Correlation analysis Emission sources PSCF

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基坑支撑轴力不同计算方法分析

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江苏建材 2022年第2期 32-34页

作者：邵欣张其立戴东东浙江省交通运输科学研究院浙江杭州311305 浙江勤业建工集团有限公司浙江绍兴312030 安徽皖通高速公路股份有限公司滁州管理处安徽滁州239000

以某城市地铁车站深基坑工程为例,通过对基坑支撑轴力不同计算方法的分析研究,结合该深基坑支护工程监测数据,对各种计算结果进行对比,确定适合本基坑的最优计算方法。

关键词：等值梁法支撑轴力弹性法弯矩

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Insights for global energy interconnection from China renewable energy development

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Global Energy Interconnection 2020年第1期3卷 1-12页

作者： qili Huang State Grid Corporation of China Xicheng DistrictBeijing 100031P.R.China

Vigorously developing global renewable energy such as wind energy,solar energy,and hydropower and realizing global clean resource sharing are paramount driving forces for building the Global Energy Interconnection(GEI).With the help of a comparative analysis of renewable energy development and global renewable energy development scenarios,this paper expounds on the similarities between China^1 and global renewable energy development.Based on the analysis of renewable energy development and the status of global renewable energy development in China,this paper summarizes the relevant experience and problems of renewable energy development in China.According to these problems,this paper also puts forward the corresponding solutions and measures,that is,to promote the healthy and steady development of renewable energy in China through the source-network-load-storage and market coordination.Finally,by analyzing the development requirements and current foundation of GEI,insights and suggestions are proposed for the future development of renewable energy for the GEI construction.

关键词： Renewable energy Global energy interconnection(GEI) Energy system Smart grid Energy storage Demand response

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A Finite Element Variational Multiscale Method for Stationary Incompressible Magnetohydrodynamics Equations

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Advances in Applied Mathematics and Mechanics 2023年第5期15卷 1142-1165页

作者： Huayi Huang Yunqing Huang qili Tang Hunan Key Laboratory for Computation and Simulation in Science and Engineering Key Laboratory of IntelligentComputing&Information Processing of Ministry of EducationSchool of Mathematics and Computational ScienceXiangtan UniversityXiangtanHunan 411105China

In this paper,we propose a variational multiscale method(VMM)for the stationary incompressible magnetohydrodynamics equations.This method is defined by large-scale spaces for the velocity field and the magnetic field,which aims to solve flows at high Reynolds numbers.We provide a new VMM formulation and prove its stability and convergence.Finally,some numerical experiments are presented to indicate the optimal convergence of our method.

关键词： Variational multiscale method stationary incompressible magnetohydrodynamics large-scale spaces stability and convergence high Reynolds numbers

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Novel insights into histone lysine methyltransferases in cancer therapy:From epigenetic regulation to selective drugs

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Journal of Pharmaceutical Analysis 2023年第2期13卷 127-141页

作者： qili Liao Jie Yang Shengfang Ge Peiwei Chai Jiayan Fan Renbing Jia Department of Ophthalmology Ninth People's HospitalShanghai Jiao Tong University School of MedicineShanghai200001China Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology Shanghai200001China

The reversible and precise temporal and spatial regulation of histone lysine methyltransferases(KMTs)is essential for epigenome homeostasis.The dysregulation of KMTs is associated with tumor initiation,metastasis,chemoresistance,invasiveness,and the immune microenvironment.Therapeutically,their promising effects are being evaluated in diversified preclinical and clinical trials,demonstrating encouraging outcomes in multiple malignancies.In this review,we have updated recent understandings of KMTs'functions and the development of their targeted inhibitors.First,we provide an updated overview of the regulatory roles of several KMT activities in oncogenesis,tumor suppression,and immune regulation.In addition,we summarize the current targeting strategies in different cancer types and multiple ongoing clinical trials of combination therapies with KMT inhibitors.In summary,we endeavor to depict the regulation of KMT-mediated epigenetic landscape and provide potential epigenetic targets in the treatment of cancers.

关键词： Cancer Epigenetics Histone lysine methyltransferase Epigenetic inhibitors Combined therapeutic strategy Clinical application

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Parallel finite element computation of incompressible magnetohydrodynamics based on three iterations

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Applied Mathematics and Mechanics(English Edition) 2022年第1期43卷 141-154页

作者： qili TANG Yunqing HUANG Hunan Key Laboratory for Computation and Simulation in Science and Engineering Key Laboratory of Intelligent Computing&Information Processing of Ministry of EducationSchool of Mathematics and Computational ScienceXiangtan UniversityXiangtanHunan Province411105China

Based on local algorithms,some parallel finite element(FE)iterative methods for stationary incompressible magnetohydrodynamics(MHD)are presented.These approaches are on account of two-grid skill include two major phases:find the FE solution by solving the nonlinear system on a globally coarse mesh to seize the low frequency component of the solution,and then locally solve linearized residual subproblems by one of three iterations(Stokes-type,Newton,and Oseen-type)on subdomains with fine grid in parallel to approximate the high frequency component.Optimal error estimates with regard to two mesh sizes and iterative steps of the proposed algorithms are given.Some numerical examples are implemented to verify the algorithm.

关键词： local and parallel algorithm finite element(FE)method iteration stationary incompressible magnetohydrodynamics(MHD)

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