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Chinese Chemical Letters 2022年第12期33卷 5196-5199页

作者： Yuxin Zeng Siyao Zhang Lifeng Yin Yunrong Dai school of environment Beijing Normal UniversityBeijing 100875China School of Water Resources and Environment China University of Geosciences(Beijing)Beijing 100083China

The increasing occurrence of pesticide micropollutants highlights the need for innovative water treatment technologies,particularly for small-community and household applications.Electro-oxidation is being widely studied in this area,unfortunately,safe,stable and efficient electrocatalytic anodes without released heavy metal ions are still highly required.In this study,we fabricated a Pt/Ti anode by high energy pulse magnetron sputtering(HiPIMS-PtTi)which was used to decompose dichlorvos(DDVP)and azoxystrobin(AZX)in water.The results show that the reaction rate constant(kENR)on HIPIMS was 35.7 min-1(DDVP)and 41.3 min-1(AZX),respectively,superior to electroplating Pt/Ti anode(EP-PtTi).The identification of radicals(^(·)OH,^(1)O_(2),^(·)O_(2)-)and micro-area analyses evidenced that Pt atoms were embedded into the TiO_(2) lattice on the surface of Ti plate by high-energy ions,which resulted in more adsorbed hydroxyls,and higher production of·OH under polarization conditions.Besides,the electro-oxidation intermediates of DDVP and AZX were identified and the degradation pathways were speculated:(1)indirect oxidation dominated by·OH attack,and(2)direct electron transfer reaction of pesticides on the anode surface.The cooperated reactions achieve the complete degradation and highly efficient mineralization of DDVP and AZX.

关键词： Electrocatalysis Magnetron sputtering Pesticide Degradation mechanism Dichlorvos Azoxystrobin

The Arc-view application in the field of hydrology and water resources

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地下水科学与工程：英文版 2017年第4期5卷 387-396页

作者： WANG Xiao-ming XUE Fei school of water resources & environment Hebei GEO University

Through system design and analysis from the aspects of entity categories, hierarchical design, attribute design, and the final function design and realization of the system, this paper develops a software application based on Arc-view platform with a view to solving the deficiencies of conventional groundwater dynamic management in managing the spatial graphics data. Using this application into the supporting automatic monitoring system of groundwater level helps to achieve the automatic analysis of attribute data, and offer a new, visual and efficient automated management tool. Moreover, the computer geospatial modeling can realize the quick query and spatial analysis of geographic information, and thus facilitating dynamic simulation and prediction of the research object. However, a multi-functional, multi-level groundwater level information management system is a complex system engineering, which requires continuous improvement of the structure, development of functions, and supplement of user models.

关键词： water level dynamics Spatial database Groundwater resources Geographic Information Systems

Streamflow responses to climate change and LUCC in a semi-arid watershed of Chinese Loess Plateau

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Journal of Arid Land 2017年第4期9卷 609-621页

作者： LI Qingyun SUN Yanwei YUAN Wenlin LYU Subing WAN Fang school of water Conservancy North China University of Water Resources and Electric Power school of water Conservancy and environment Zhengzhou University

Climate change and Land Use/Cover Change（LUCC） have been identified as two primary factors affecting watershed hydrological regime. This study analyzed the trends of streamflow, precipitation, air temperature and potential evapotranspiration（PET） from 1962 to 2008 in the Jihe watershed in northwestern Loess Plateau of China using the Mann-Kendall test. The streamflow responses to climate change and LUCC were quantified independently by the elasticity method. The results show that the streamflow presented a dramatic decline with a turning point occurred in 1971, while the precipitation and PET did not change significantly. The results also show that the temperature rose markedly especially since 1990 s with an approximate increase of 1.74°C over the entire research period（1962–2008）. Using land use transition matrix, we found that slope cropland was significantly converted to terrace between 1970 s and 1990 s and that forest cover increased relatively significantly because of the Grain for Green Project after 2000. The streamflow reduction was predominantly caused by LUCC and its contribution reached up to 90.2%, while the contribution of climate change to streamflow decline was only 9.8%. Although the analytical results between the elasticity method and linear regression model were not satisfactorily consistent, they both indicated that LUCC（human activity） was the major factor causing streamflow decline in the Jihe watershed from 1962 to 2008.

关键词： streamflow LUCC climate change Mann-Kendall test elasticity method Loess Plateau

Study of fate and transport of chromium in unsaturated zonesaturated zone

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Acta Geologica Sinica(English Edition) 2017年第S1期91卷 168-169页

作者： Yan baizhong Yu Furong school of water resources & environment Hebei GEO University Hebei Province Key Laboratory of Sustained Utilization & Development of water resources school of resources and environment North China University of Water Resources and Electric Power

Effluent irrigation can ease the water shortage area agricultural water shortage,and waste-water recycling,as well as bring a series of scientific and socio-economic issues,such as environmentalissues,food safety,sustainable development and so on,which has attracted the attention of people.So,paper to Kaifeng city several important dirt irrigation district for

关键词： Cr soil rate Study of fate and transport of chromium in unsaturated zonesaturated zone VI

Instantaneous sediment transport formula for sheet flow beneath asymmetric wave and current

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Journal of Hydrodynamics 2022年第4期34卷 712-724页

作者： Xin-yu Hu Zhong-hua Weng Xin Chen Hai-fei Liu The Key Laboratory of water and Sediment Sciences of Ministry of Education School of EnvironmentBeijing Normal UniversityBeijing100875China Pearl River water resources Research Institute Pearl River Water Resources CommissionGuangzhou 510611China College of water resources and Civil Engineering China Agricultural UniversityBeijing 100083China

An instantaneous formula is obtained for the sheet flow transport beneath the wave and the current by a product integration of the concentration and velocity profiles over the mobile seabed. The formula involves: (1) The product of the erosion depth and the free stream velocity, which can be reduced to the Shields parameter of power 3/2 in accordance with the classical formulae. (2) The ratio of the wave boundary layer thickness to the erosion depth. The formula incorporates the effects of the acceleration and the phase lag on the erosion depth, the asymmetric wave boundary layer and the wave-current interaction. The validation of the formula is made by the data obtained from the oscillatory tunnels covering a wide range of wave-current and sediment conditions. The instantaneous sediment transport rate is compared with the power function of the velocity with different exponents. The formula consists of a wave force part and a current force part and their relative importance depends on the wave shapes. The present formula gives very good results for the net sediment transport as compared to several existing steady and unsteady formulae. The net sediment transport rates are affected by not only the acceleration, the phase lag and the wave-current interaction, but also the asymmetric boundary layer development.

关键词： Boundary layer thickness erosion depth instantaneous formula sediment transport rate wave and current

Modeling the effect of artificial flow and sediment flux on the environment and plankton of an estuary

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International Journal of Sediment Research 2023年第3期38卷 335-348页

作者： Yujun Yi Yanning Gao Xuefei Wu Wenfei Jia Qi Liu Ministry of Education Key Laboratory of water and Sediment Science School of Environment Beijing Normal University State Key Laboratory of water environment Simulation School of Environment Beijing Normal University

Estuarine environments are influenced by both river flows and oceanic tidal movement of water, sediment, and nutrients, often forming ecosystems that are rich in resources and biodiversity. The Yellow River once carried the world’s largest sediment load, but artificial structures have transformed its hydrodynamic processes. An annual water-Sediment Regulation Scheme(WSRS) was introduced to flush accumulated sediment from the Xiaolangdi Reservoir, which provides flood control and water storage.However, the effect of the WSRS process on the runoff and sediment conditions, nutrients, and ecological environment of the Yellow River Estuary and adjacent ocean are not well understood. In the current study, a coupled hydrodynamic-nutrient-plankton ecosystem dynamics model(FVCOM-FABM-NPZD)was constructed to simulate changes in the ecological parameters and in the vertical response in the Yellow River Estuary before, during, and after the WSRS, This model also was used to quantify the effects of changes in the incoming material flux on the hydrodynamic and ecological environment of the estuary, using the Yellow River Xiaolangdi Reservoir water transfer and sand transfer as an example. The study found that the WSRS changed the spatial and temporal distribution of temperature, salinity,sediment, inorganic nitrogen, and phytoplankton in the Yellow River Estuary and adjacent waters. It also had a significant effect on the temperature, salinity, and ecology of the adjacent near-shore marine environment. The spatial and temporal responses of zooplankton and phytoplankton to the WSRS differed. Zooplankton showed a lag in response to the WSRS and were mainly influenced by temperature and phytoplankton. The phytoplankton concentration was positively influenced by inorganic nitrogen and negatively influenced by salinity and sediment. In the current study, the effects of changes in the flow and sediment flux from the WSRS on environmental factors and zooplankton in the Yellow River Estuary were simulated, providing a theoretical basi

关键词： environments Estuarine dynamics FVCOM NPZD Plankton Yellow River Estuary

Revealing the effect of preparation parameters on zeolite adsorption performance for low and medium concentrations of ammonium

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Journal of environmental Sciences 2019年第11期31卷 177-188页

作者： Wenyan He Hui Gong Kuo Fang Fei Peng Kaijun Wang State Key Joint Laboratory of environment Simulation and Pollution Control School of Environment Tsinghua University Beijing 100084China school of water resources & environment China University of Geosciences Beijing 100083 China

The effect of preparation parameters on the performance of zeolite for ammonium (20-300 mg N/L) adsorption from simulated wastewater is reported.It was found that the ratios of Na2O/SiO2 and Si/Al had a more important influence than crystallization time on zeolite adsorption properties.Relatively low Na2O/SiO2 ratios were beneficial for fabrication of zeolites with high proportions of micropore area and volume,which led to the surface adsorption mechanism being dominated by surface free energy and pore effects.However,with decreasing Si/Al ratios,the effect of ion-exchange was more prominent due to the high negative surface potential of zeolite.In addition,the concentration of weak acid sites on the zeolites was increased with lower ratios of Na2O/SiO2 and Si/Al,which may promote ammonium removal.Therefore,the most effective zeolite for ammonium removal,which was fabricated at Na2O/SiO2 =1.375,Si/Al =4 and crystallization time of 48 hr,exhibited the cooperative effects of adsorption,ion-exchange and a large amount of weak acid sites.The maximum ammonium adsorption capacity (35.06 t 0.98 mg/g) and the removal efficiency (94.44%± 4.00%) were obtained at the dosage of 4.0 g/L zeolite NaX at ammonium concentrations of 300 mg N/L and 20 mg N/L,respectively.The Freundlich isotherm and pseudo-first-order kinetics models provided excellent fitting for the ammonium adsorption process.In addition,zeolite NaX showed about 1.23-3.2 times the ammonium adsorption capacity of clinoptilolite.The stable and efficient reusability of zeolite NaX after five regeneration cycles demonstrated that this adsorbent has considerable potential for practical industrial applications.

关键词： Zeolite synthesis Ammonium nitrogen removal Ion exchange Performance optimization

Chemical characteristics of rainwater in karst rural areas,Guizhou Province, Southwest China

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Acta Geochimica 2017年第3期36卷 572-576页

作者： Pin Lü Guilin Han Qixin Wu School of Water Resources and Environment China University of Geosciences (Beijing) Key Laboratory of Karst environment and Geohazard Ministry of Land and Resources Guizhou University

The chemical composition of rainwater has been studied in a karst rural area from September 2012 to August 2013 in Guizhou Province,Southwest China.The results indicated that the VWM value of p H was 5.4,varied from 4.6 to 6.9.Ca^(2+)and NH_4^+were the major cations,and SO_4^(2-)was the dominant anion.Neutralization factors show that the acid was mainly neutralized by Ca^(2+),NH_4^+and Mg^(2+).Investigations of correlation coefficients and enrichment factors revealed that Ca^(2+)and Mg^(2+)were mainly crust origins,and NH_4^+was from agriculture and livestock manure.SO_4^(2-)and NO_3^-were mainly from anthropogenic sources.

关键词：中国西南部农村地区喀斯特贵州省雨水化工化学成分富集因素

Soil-Air Partitioning of Polychlorinated Biphenyls and Total Dichloro-Diphenyl-Trichloroethanes

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Journal of Earth Science 2014年第4期25卷 741-748页

作者： Yaping Zhang Erping Bi Honghan Chen School of Water Resources and Environment China University of Geosciences (Beijing) Beijing Key Laboratory of water resources and environment Engineering China University of Geosciences (Beijing)

Soil-air partitioning is an important diffusive process that affects the environmental fate of organic compounds and human health. In this review, factors affecting the soil-air partitioning of polychlorinated biphenyls （PCBs） and total dichloro-diphenyl-trichloroethanes （p,p＇- and o,p＇- isomers of DDT, DDD, and DDE） are discussed. Hydrophobicity is an important factor that influences soil-air partition coefficients （KsA）, and its effect can be explained through enthalpy of phase change for soil-air partitioning transfer （AHsA）. For more hydrophobic compounds, a sharp increase in the KSA of PCBs and organochlorines can be seen in the early aging period. During the aging period, the temperature has a significant effect on the more hydrophobic organic compounds. The content and properties of soil or- ganic matter influence the KSA of the target compounds. Generally, KSA decreases with increasing rela- tive humidity in soils. The linear trend between KSA and temperature （T） changes at 0 ~C. Freezing the air or soil in experiments would change the research results. On the basis of factors influencing soil-air partitioning, a multipleparameter （T, organic carbon fraction （foe）, and octanol-air partition coefficient （KoA）） model is put forward to predict the KSA values for PCBs and total DDTs.

关键词： soil-air interface partition sorption polychlorinated biphenyl （PCB） dichloro-diphenyltrichloroethanes （DDT）.

Hydrochemistry and H-O-C-S Isotopic Geochemistry Characteristics of Geothermal water in Nyemo-Nagqu,Tibet

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Acta Geologica Sinica(English Edition) 2017年第2期91卷 644-657页

作者： WANG Siqi LIU Zhao SHAO Jingli School of Water Resources and Environment China University of GeosciencesBeijing 100083China school of water resources&environment Hebei GEO UniversityShijiazhuang 050031China Hebei Province Key Laboratory of Sustained Utilization&Development of water resources Shijiazhuang 050031China

Nyemo-Nagqu, Tibet, is rich in high-temperature geothermal resources. The geothermal fields in Yangbajain and Yangyi as well as 11 unexplored geothermal fields along the geothermal belt from Nyemo to Nagqu were systematically investigated and the hydrochemistry data were collected from the whole field. Meanwhile, H-O-C-S isotope data were obtained for the new fields, and H-O isotope data for the Yangbajain and Yangyi fields. A comparison of the Nyemo-Nagqu geothermal fields with those in the Yangbajain area shows that the types of high-temperature geothermal water are dominated by Cl-Na and Cl·HCO3-Na, while the types of medium-high-temperature geothermal water are dominated by HCO3-Na. The concentrations of Li, F, SiO2, and HBO2 in the geothermal water are positively correlated with Cl content, indicating possible mixing with magma water. The reservoir temperatures range from 90 to 270°C by geothermometers. Slight drifting of 18O was recorded at the Dongweng and Nyingzhong high-temperature geothermal fields, while more significant drifting was recorded at Gulu. The geothermal water is mainly replenished by atmospheric precipitation. The low tritium contents（〈1 TU） of the geothermal water from Nyingzhong, Gulu, and Luoma indicate that it is mainly replenished by sub-modern（prior to 1952） water, while the high tritium content（8.4 TU） in Yuela implies modern water replenishment. Other geothermal fields are replenished by a mix of sub-modern fresher water. The isotopic data in this study show that the carbon and sulfur in the geothermal water originates mainly from sediment leaching, with some of the carbon and sulfur having a deep origin.

关键词： geothermal water hydrochemical characteristics isotope data Tibet Proto-Tethys