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Estimation of the accumulation rates and health risks of heavy metals in residential soils of three metropolitan cities in China

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Journal of Environmental Sciences 2022年第5期34卷 149-161页

作者： Chi Peng Kai Zhang Meie Wang Xinxing Wan Weiping Chen Institute of Environmental Engineering School of Metallurgy and EnvironmentCentral South UniversityChangsha 410083China State key laboratory of urban and regional ecology Research center for eco-environmental sciencesChinese academy of sciencesBeijing 100085China Third Xiangya Hospital Central South UniversityChangsha 410013China

Heavy metal concentrations in urban soils are likely to increase over time because of contin-uous urbanization and heavy metal emissions.To estimate the accumulation rates of heavy metals in urban soils,we collected soil samples from residential areas with different build-ing ages in the metropolitan cities of Shanghai,Shenzhen,and Beijing,China.Heavy metal concentrations in the soils varied among the cities and were primarily affected by soil parent material and the intensity of anthropogenic sources.Regression analyses revealed that the accumulation rates of Cd and Cu in the soils ranged from 0.0034 to 0.0039 mg/(kg·year)and 0.343 to 0.391 mg/(kg·year),respectively,and were similar across the three cities,while ac-cumulation rates of Zn and Pb in Shanghai were higher than those in Shenzhen and Beijing.The higher accumulation rates of Zn and Pb in Shanghai can be explained by differences in city history and industrial structures among the cities.Residential soils with high health risks posed by the heavy metals were mostly collected from old towns of Shanghai because of high Pb content in the areas.Although recent urbanization resulted in elevated concen-trations of Cd,Cu,Zn,and Pb in the residential soils,the effect on the total health risks of residents exposed to the soils was negligible.

关键词： Urbanization Urban soil Health risk assessment Building age Regression model Source analysis

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Evaluation of joint toxicity of heavy metals and herbicide mixtures in soils to earthworms(Eisenia fetida)

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Journal of Environmental Sciences 2020年第8期32卷 137-146页

作者： Xuzhi Li Meie Wang Rong Jiang Liping Zheng Weiping Chen State Key Laboratory of Urban and Regional Ecology Research Centre for Eco-environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control Nanjing Institute of Environmental SciencesMinistry of Ecology and EnvironmentNanjing 210042China

It is widely acknowledged that a simplified and robust approach to evaluating thecombined effects of chemical mixtures is critical for ecological risk assessment(ERA)of contaminated soil.The earthworm(Eisenia fetida)was used as a model to study the combined effects of polymetallic contamination and the herbicide siduron in field soil using a microcosm experiment.The responses of multiple biomarkers,including the activities of catalase(CAT),superoxide dismutase(SOD),glutathione reductase(GR)and acetylcholine esterase(AChE),the concentrations of glycogen,soluble protein(SP),malonaldehyde(MDA),and metallothionein(MT),and the neutral red uptake test(NRU),were investigated.Multivariate analysis,Principal Component Analysis(PCA)and Spearman’s Rank Correlations analysis(BVSTEP)revealed that the activities of AChE and CAT and the NRU content were the prognostic biomarkers capturing the minimum data set of all the variables.Internal Cd(tissue Cd)in earthworms was closely related to the health status of worms under combined contamination of heavy metals and siduron.The integrated effect(E mix)calculated based on the activities of AChE and CAT and NRU content using the stress index method had significantly linear regression with internal Cd(p<0.01).E mix(10),E mix(20),and E mix(50)were then calculated,at 1.27,1.63 and 2.71 mg/kg dry weight,respectively.It could be concluded that a bioassaybased approach incorporating multivariate analysis and internal dose was pragmatic and applicable to evaluating combined effects of chemical mixtures in soils under the guidance of the top-down evaluation concept of combined toxicity.

关键词： Siduron Polymetallic contamination Multiple biomarker responses Multivariate analysis Bioaccumulation

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Microstructure and Mechanical Behavior of FeNiCoCr and FeNiCoCrMn High-Entropy Alloys Fabricated by Powder Metallurgy

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Acta Metallurgica Sinica(English Letters) 2021年第4期34卷 445-454页

作者： chenliang Chu Weiping Chen Zhen chen Zhenfei Jiang Hao Wang Zhiqiang Fu Guangdong Key Laboratory for Advanced Metallic Materials Processing South China University of TechnologyGuangzhou 510640China Shantou Technician College Shantou 515041China

The present work reports a systematic investigation on phase evolution,microstructure and microstructure-property relationship of two typical face-centered cubic(FCC)structured high-entropy alloys(HEAs),FeNiCoCr and FeNiCoCrMn,prepared via mechanical alloying(MA)followed by spark plasma sintering(SPS).Following 50 h of MA,the two HEAs consisted of a mixture of FCC and body-centered cubic phases.Following SPS,the bulk FeNiCoCr alloy showed a primary FCC phase with a small amount of Cr_(23)C_(6) and Cr_(2)O_(3) contaminants,while the bulk FeNiCoCrMn alloy was composed of a primary FCC phase with some(Cr,Mn)23C6 and MnCr_(2)O_(4) contaminants.The average grain size of the primary FCC phase in the bulk FeNiCoCr alloy was~416 nm,while that of the primary FCC phase in the bulk FeNiCoCrMn alloy was~547 nm.The yield strength,compressive strength and strain-to-failure of the bulk FeNiCoCr alloy are 1525 MPa,1987 MPa and 24.4%,respectively,whereas those of the bulk FeNiCoCrMn alloy are 1329 MPa,1761 MPa and 21.9%,respectively.It suggests that the bulk FeNiCoCrMn exhibited lower strength and plasticity in comparison with the bulk FeNiCoCr alloy.Clearly,the smaller grain size of the primary FCC phase in the FeNiCoCr alloy is mainly responsible for the better mechanical performance.

关键词： High-entropy alloy Mechanical alloying Microstructure Strengthening Contaminants

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Long-term and short-term stability characteristics of receiver inter system bias for BDS3/BDS2

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Geodesy and Geodynamics 2023年第2期14卷 143-149页

作者： Jingxuan Guo weiping Jiang Yan chen Xincheng Ma Hua chen GNSS Research Center Wuhan University129 Luoyu RoadWuhan 430079China CCCC Highway Consultants Co. LTD.85 Dewai StreetXicheng DistrictBeijing 100088China School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan 430079China

The study of inter-system bias(ISB)is important for multi-system fusion and the performance of different signal compatibility.In this paper,the stability of ISB at the BDS3/BDS2 receiver end is calculated and analyzed for different time spans(DOY 060~090 in 2021)from a total of 31 MGEX and iGMAS stations.We adopted two estimation strategies,random walk and constant approach,using the precision products of orbit and clock bias provided by WUM,the influence of which on ISB was also analyzed.Our results showed that the ISB value varied little within a day,and the mean of daily ISB standard deviation was only 0.037 m when the observation condition was good.The signal reception was continuous,indicating a high ISB stability for one day.If extending the time series to one month,however,the ISB standard deviation calculated by constant approach,in which a constant ISB is estimated on a daily basis was about 0.1 m,and the results of adjacent days were not continuous,with no apparent pattern.Concerning the random walk approach,the obtained ISB time series also had a jump,and the conclusion was the same as that of the constant strategy.Besides,receiver types showed a strong regularity in ISB numerical situation,and the distribution of ISB values corresponding to the same receiver type was relatively close.Therefore,we conclude that the ISB parameters remain stable in the short term(one day)and less stable in the long-term period.It is recommended that the ISB term should be set as a constant estimate every day in BDS3/BDS2 solutions,regardless of receiver type consistency.

关键词： BDS3 BDS2 Inter system bias Stability analysis Receiver type

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Tail Distortion Risk Measure for Portfolio with Multivariate Regularly Variation

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Communications in Mathematics and Statistics 2022年第2期10卷 263-285页

作者： Yu chen Jiayi Wang weiping Zhang Department of Statistics and Finance University of Science and Technology of ChinaHefei 230026China

For the multiplicative background risk model,a distortion-type risk measure is used to measure the tail risk of the portfolio under a scenario probability measure with multivariate regular variation.In this paper,we investigate the tail asymptotics of the portfolio loss ∑_(i=1)^(d)R_(i)S,where the stand-alone risk vector R=(R_(1),...,R_(d))follows a multivariate regular variation and is independent of the background risk factor S.An explicit asymptotic formula is established for the tail distortion risk measure,and an example is given to illustrate our obtained results.

关键词： Background risk model Tail distortion risk measure Multivariate regular variation

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An overview of reclaimed water reuse in China

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Journal of Environmental Sciences 2011年第10期23卷 1585-1593页

作者： Lili Yi Wentao Jiao Xiaoning chen Weiping Chen State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijin g 100085 China School of Social Sciences University of California Irvine CA 92697 USA

China is facing severe water problems including scarcity and pollution which are now becoming key factors restricting developments. Creating an alternative water resource and reducing effluent discharges, water reuse has been recognized as an integral part of water and wastewater management scheme in China. The government has launched nationwide efforts to optimize the benefits of utilizing reclaimed water. This article reviewed the water reuse activities in China, including：（1） application history and current status; （2） potentials of reclaimed water reuse; （3） laws, policies and regulations governing reclaimed water reuse; （4） risks associated with reclaimed water reuse; （5） issues in reclaimed water reuse. Reclaimed water in Beijing and Tianjin were given as examples. Suggestions for improving the efficiencies of reusing urban wastewater were advanced. Being the largest user of reclaimed wastewater in the world, China＇s experience can benefit the development of water reuse in other regions.

关键词： water management water crisis recycling

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Effects of urbanization on heavy metal accumulation in surface soils, Beijing

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Journal of Environmental Sciences 2018年第2期30卷 328-334页

作者： Meie Wang Rui Liu Weiping Chen Chi Peng Bernd Markert State Key Laboratory of Urban and Regional Ecology Research Centre for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Environmental Institute of Scientific Networks 49733 Haren Germany

Urbanization processes affect the accumulation of heavy metals in urban soils. Effects of urbanization on heavy metal accumulation in soils were studied using Beijing as an example. It has been suggested that the ecological function of vegetation covers shifting from natural to agricultural settings and then to urban greenbelts could increase the zinc（Zn） concentrations of soils successively. The Zn concentration of urban soils was significantly correlated to the percentage of the impervious land surface at the500 m × 500 m spatial scale. For urban parks, the age or years since the development accounted for 80% of the variances of cadmium（Cd） and Zn in soils. The population density,however, did not affect the heavy metal distributions in urban soils. To conclude, the urban age turned out to be a notable factor in quantifying heavy metal accumulation in urban soils.

关键词： Urban soils Human disturbance Zn Impervious land Population density

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Regression Estimation for Longitudinal Data with Nonignorable Intermittent Nonresponse and Dropout

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Communications in Mathematics and Statistics 2022年第3期10卷 383-411页

作者： weiping Zhang Dazhi Zhao Yu chen Department of Statistics and Finance University of Science and Technology of ChinaHefei 230026People’s Republic of China

We mainly focus on regression estimation in a longitudinal study with nonignorable intermittent nonresponse and dropout.To handle the identifiability issue,we take a time-independent covariate as nonresponse instrument which is independent of nonresponse propensity conditioned on other covariates and responses to ensure the identifiability of nonresponse propensity.The nonresponse propensity is assumed to be a parametric model,and the corresponding parameters are estimated by using the generalized method of moments approach.Then the marginal response means are estimated by inverse probability weighting method.Furthermore,to improve the robustness of estimators,we derive an augmented inverse probability weighting estimator which is shown to be consistent and asymptotically normally distributed.Simulation studies and a real-data analysis show that the proposed approach yields highly efficient estimators.

关键词： Dropout Generalized method of moments Inverse probability weighting Intermittent nonresponse Longitudinal data

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Wastewater reclamation and reuse in China:Opportunities and challenges

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Journal of Environmental Sciences 2016年第1期28卷 86-96页

作者： Sidan Lyu Weiping Chen Weiling Zhang Yupeng Fan Wentao Jiao State Key Laboratory for Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

The growing water stress both in terms of water scarcity and quality deterioration promotes the development of reclaimed water as a new water resource use. This paper reviewed wastewater reuse practices in China, and the opportunities and challenges of expanding reclaimed water use were analyzed. Rapid urbanization with the increasing of water demand and wastewater discharge provides an opportunity for wastewater reuse. The vast amount of wastewater discharge and low reclaimed water production mean that wastewater reuse still has a great potential in China. Many environmental and economic benefits and successful reclamation technologies also provide opportunities for wastewater reuse. In addition, the overall strategy in China is also encouraging for wastewater reuse. In the beginning stage of wastewater reclamation and reuse, there are many significant challenges to expand wastewater reuse in China including slow pace in adopting urban wastewater reuse programs, the establishment of integrated water resources management framework and guidelines for wastewater reuse programs, incoherent water quality requirements, the limited commercial development of reclaimed water and the strengthening of public awareness and cooperation among stakeholders.

关键词： Wastewater reuse Urbanization Policy Integrated water resource management Public acceptance

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An Analysis of Anti-Traditionalism in the New Culture Movement

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Social Sciences in China 2017年第2期38卷 175-187页

作者： chen weiping Institute for Modern Chinese Thought and Culture and Department of Philosophy at the East ChinaNormal University

新文化运动所要“猛勇”攻击的，是封建专制主义，并通过清除传统文化当中沉淀的渣滓，达到重建新文化之基础的目标。同时，新文化运动对于中国优秀的传统文化，并非持全盘否定的态度，而是在破除经学传统之时，强调以科学精神研究传统... 详细信息

新文化运动所要“猛勇”攻击的，是封建专制主义，并通过清除传统文化当中沉淀的渣滓，达到重建新文化之基础的目标。同时，新文化运动对于中国优秀的传统文化，并非持全盘否定的态度，而是在破除经学传统之时，强调以科学精神研究传统文化，将其思想纳入现代学科体系当中而使之重新焕发生机。

关键词：新文化运动优秀文化传统现代科学体系

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