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The coupling between hydrodynamic and purification efficiencies of ecological porous spur-dike in field drainage ditch

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Journal of Hydrodynamics 2018年第3期30卷 373-383页

作者： Lei Rao pei-fang wang Qing-song Dai Chao wang College of Mechanics and Materials Hohai University Nanjing 211100 China Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry of Education Hohai University Nanjing 210098 China College of Environment Hohai University Nanjing 210098 China

In this study, a series of ecological porous spur-dikes are arranged in an experiment channel to simulate a real field drainage ditch. The inside and outside flow fields of spur-dikes are determined by numerical simulations and experimental methods. An Ammonia-Nitrogen（NH3-N） degradation evaluation model is built to calculate the pollution removal rate by coupling with the inner flow field of the porous spur-dikes. The variations of the total pollutant removal rate in the channel are discussed in terms of different porosities and gap distances between spur-dikes and inlet flow velocities. It is indicated that a reasonable parameter matching of the porosity and the gap distance with the flow velocity of the ditch can bring about a satisfactory purification efficiency with a small delivery quantity of ecological porous materials.

关键词： Porous water permeable material ecological spur-dike field drainage ditch pollutant removal rate coupling

Influence of cascade reservoirs on spatiotemporal variations of hydrogeochemistry in Jinsha River

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Water Science and Engineering 2021年第2期14卷 97-108页

作者： Qiu-sheng Yuan pei-fang wang Juan Chen Chao wang Sheng Liu Xun wang Key Laboratory of Integrated Regulation and Resources Development of Shallow Lakes Ministry of EducationHohai UniversityNanjing 210098China

River hydrogeochemistry offers necessary guidance for effective water environmental ***,the influence of cascade reservoirs on river hydrogeochemistry remains *** this study,the Jinsha River,the headwaters of the Yangtze River of China,was selected to investigate the spatiotemporal variations of hydrogeochemistry after the construction of six cascade *** ions,total dissolved solids,electrical conductivity,and pH values of sampled water in the upper natural reaches and lower reservoir-regulated reaches were analyzed in both flood and dry *** results of Piper diagram and Gibbs plots showed that the hydrogeochemistry of the Jinsha River was naturally controlled by both evaporation-crystallization and carbonate weathering processes,but it was also artificially affected by *** impoundment of cascade reservoirs affected the hydrodynamic condition of the *** river flow in the flood season was reduced by approximately 24.5%,altering the proportions of water sources and leading to notable hydrogeochemical alterations in reservoir-regulated ***,river hydrogeochemistry generally remained unchanged in the dry season,owing to the insignificant effect of cascade reservoirs on river *** contrast to what has been observed in previous studies of individual reservoirs,the cumulative influence of cascade reservoirs on the Jinsha River flow regime did not cause abrupt hydrogeochemical changes between the upstream and downstream areas of each ***,the water quality assessments revealed that the impoundment of cascade reservoirs improved downstream irrigational water quality,with lower Naþratio values in the flood *** study provides the earliest evaluation of cascade reservoir influence on the hydrogeochemistry of the Jinsha *** findings of this study can be used as a reference for scientific guidelines for future environmental management of cascade reservoirs in large rivers.

关键词： River hydrogeochemistry Spatiotemporal variations Controlling factors Cascade reservoirs Jinsha River

EXPERIMENTAL STUDY ON SEDIMENT RESUSPENSION IN TAIHU LAKE UNDER DIFFERENT HYDRODYNAMIC DISTURBANCES

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Journal of Hydrodynamics 2011年第6期23卷 826-833页

作者： QIAN Jin ZHENG Sha-sha wang pei-fang wang Chao Key Laboratory of Integrated Regulation and Resource Department on Shallow Lakes Ministry of Education and College of Enviroment Hohai University Nanjing 210098 China

Contaminants resuspension in sediments induced by wind-wave could influence the water quality in shallow lakes. Resuspension of surface sediments from the Zhushan Bay, Taihu Lake was simulated under different wind forcing by using a pneumatic annular flume in this study. Acoustic Doppler Velocimeter （ADV） was used to measure flow velocity at each wind speed, and the characteristics of sediment resuspension were studied with the layered sampling technology. The experimental results show that the flow velocity increases with wind speed obviously and 6m/s is a critical wind speed which affected hydrodynamic conditions significantly. The distribution of flow velocity and water depth is different from that in ordinary open channel. With the enhanced hydrodynamic factors, the Suspended Solids Concentration （SSC） in water increases accordingly, and the incipient velocity of sediment resuspension is about 0.21 m/s. Based on the analysis of wind speed and average SSC in water column, the quantitative relationship is obtained. The SSC of the bottom layer is higher than the content of surface layer under different hydrodynamic conditions, and there are similar distributions between SSC and flow velocity in different water layers.

关键词： hydrodynamic disturbance sediment resuspension wind speed flow velocity

Sediment resuspension under action of wind in Taihu Lake,China

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International Journal of Sediment Research 2015年第1期30卷 48-62页

作者： Sha-sha ZHENG pei-fang wang Chao wang Jun HOU Key Laboratory of Integrated Regulation and Resource Department on Shallow Lakes Ministry of EducationCollege of EnvironmentHohai University College of Environment Hohai University

A field study was undertaken to investigate the changes of the current speed,wave parameters and sediment resuspension under different wind speeds in the Taihu *** Acoustic Doppler Current Profiler(ADCP) and MIDAS DWR Wave Recorder were used to collect the data of currents and waves,*** characteristics of sediment resuspension were investigated by a layered sampling *** measurement results showed that the current speed increased in direct proportion with the wind *** distributions of the current speed represented significant inflection points at 0.4 of the relative water *** the upper and lower layers followed logarithmic *** mean wind speed and wave parameters(wave height and wave energy density) showed exponential distributions,meanwhile similar distribution was found between the mean wind speed and current *** rising surface wind,a corresponding increase in the concentration and particle size of the Suspended Particulate Matter(SPM) was observed in the water *** kinds of particles could influence the SPM concentration in the water *** critical wind speed of sediment resuspension and the corresponding sediment incipient shear stress was found to be 3.7-4.0 m s-1and 0.011 N m-2,*** results of this study can be used to help understand and predict the changes of flow structure and water quality induced by different wind disturbances in shallow lakes.

关键词： Wind disturbance Current Wave Sediment resuspension Taihu Lake

Distribution characteristics and controlling factors of typical antibiotics and antibiotic resistance genes in river networks in western area of wangyu River,China

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Water Science and Engineering 2022年第4期15卷 318-327页

作者： Jing-jing Zhang Juan Chen Chao wang pei-fang wang Han Gao Yu Hu Key Laboratory of Integrated Regulation and Resource Department on Shallow Lakes Ministry of EducationHohai UniversityNanjing 210098China College of Environment Hohai UniversityNanjing 210098China

Antibiotics and antibiotic resistance genes(ARGs)pose health risks in aquatic environments because of their persistence and *** networks can provide a perfect opportunity for exploring the occurrence and enrichment of ARGs and antibiotics in freshwater *** this basis,the abundances of four types of antibiotics(sulfonamides,quinolones,tetracyclines,and macrolides)and 13 ARGs(sulⅠ,sulⅡ,tetA,tetB,tetO,tetW,qnrA,qnrS,qnrD,ermB,ermF,ermC,and ere A)were measured in the river networks of the west bank of the wangyu River in *** spatial distribution and temporal variation of these antibiotics and ARGs were characterized,and their controlling factors were *** four types of antibiotics were detected with high frequencies between 41%and 100%.Quinolone antibiotics exhibited the highest average concentration(286.53 ng/L).The concentrations of quinolones,tetracyclines,and macrolides were significantly higher in the winter than in the summer,whereas the concentration of sulfonamides was higher in wet periods than in dry *** the 13 ARGs,sulⅠwas the most abundant(1.28 x 10^(5)copies per milliliter),followed by sulⅡand tetO(5.41×10^(4)and 4.45×10^(4)copies per milliliter,respectively).The canonical correspondence analysis showed that environmental factors,including dissolved oxygen,water temperature,total nitrogen,pH,and total phosphorus,had significant effects on the abundance of ***Ⅰ,sulⅡ,tetA,and tetB were significantly correlated with 16S ribosomal RNA sequences,indicating that the bacterioplankton community might affect the distribution of *** correlation heat map analysis showed that the spread of ARGs was influenced by specific bacterial groups,such as Acidobacteria and Cyanobacteria,indicating that these bacterioplankton may be the hosts of environmental ARGs.

关键词： wangyu river Antibiotic ARG Distribution characteristic Environmental factor River network

HYDRAULIC RESISTANCE OF SUBMERGED VEGETATION RELATED TO EFFECTIVE HEIGHT

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Journal of Hydrodynamics 2010年第2期22卷 265-273页

作者： wang pei-fang wang Chao ZHU David Z. Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry of EducationCollege of Environmental Hohai University Nanjing 210098 China Department of Civil and Environmental Engineering University of Alberta Edmonton Canada T6G 2W2

Submerged vegetation has a significant impact on water flow *** investigations include the impact through adding drag resistance and increasing bottom roughness coefficient,which cannot elucidate the characters of real submerged *** evaluate the effects of submerged vegetation on water currents at different velocities,a laboratory experiment was conducted using three kinds of *** effective heights of these vegetations on varying flow velocities were *** equation describing the relationship between the normalized resistance of the submerged plants and the Reynolds number based on the plant effective height was then established and used to calculate the hydraulic resistance parameters of submerged plants in different stages of growth.

关键词： hydraulic resistance submerged vegetation drag force effective height

Influence of cutterhead opening ratio on soil arching effect and face stability during tunnelling through non-uniform soils

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Underground Space 2024年第4期17卷 45-59页

作者： Xue-Jian Chen pei-pei fang Qiu-Nan Chen Jun Hu Kai Yao Yong Liu State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan 430072China Hubei Technology Innovation Center for Smart Hydropower Wuhan 430000China College of Civil Engineering Anhui Jianzhu UniversityHefei 230601China School of Civil Engineering Hunan University of Science and TechnologyXiangtan 411201China School of Civil and Architectural Engineering Hainan UniversityHaikou 570228China School of Qilu Transportation Shandong UniversityJinan 250002China

Tunnelling has increasingly become an essential tool in the exploration of underground space.A typical construction problem is the face instability during tunnelling,posing a great threat to associated *** face instability often occurs with the soil arching *** study investigates the combined effect of cutterhead opening ratio and soil non-uniformity on soil arching effect and face stability,via conducting random finite-element analysis coupled with Monte–Carlo *** results underscore that the face stability is strongly associated with the evolution of stress *** obtained stability factors in the uniform soils can serve as a reference for the design of support pressure in practical tunnelling *** addition,non-uniform soils exhibit a lower stability factor than uniform soils,which implies that the latter likely yields an underestimated probability of face *** tunnel face is found to have a probability of failure more than 50%if the spatial non-uniformity of soil is *** the end,a practical framework is established to determine factor of safety(FOS)corresponding to different levels of probability of face failure considering various opening ratios in non-uniform *** required FOS is 1.70 to limit the probability of face instability no more than 0.1%.Our findings can facilitate the prediction of probability of instability in the conventionally deterministic design of face pressure.

关键词： Tunnel Face stability Soil arching effect Cutterhead opening ratio Non-uniform soil Random field

Electrochemical converting ethanol to hydrogen and acetic acid for large scale green hydrogen production

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Nano Research 2024年第3期17卷 1542-1551页

作者： Yufeng Zhang Wei Zhu Jinjie fang Zhiyuan Xu Yanrong Xue Jiajing pei Rui Sui Xingdong wang Xuejiang Zhang Zhongbin Zhuang State Key Lab of Organic-Inorganic Composites and Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Laboratory of Advanced Functional Materials of Nanjing Nanjing Xiaozhuang UniversityNanjing 211171China Beijing Key Laboratory of Energy Environmental Catalysis Beijing University of Chemical TechnologyBeijing 100029China

Electrochemical coupling hydrogen evolution with biomass reforming reaction(named electrochemical hydrogen and chemical cogeneration(EHCC)),which realizes green hydrogen production and chemical upgrading simultaneously,is a promising method to build a carbon-neutral ***,we analyze the EHCC process by considering the market *** ethanol to acetic acid and hydrogen approach is the most feasible for large-scale hydrogen *** develop AuCu nanocatalysts,which can selectively oxidize ethanol to acetic acid(>97%)with high long-term *** isotopic and in-situ infrared experiments reveal that the promoted water dissociation step by alloying contributes to the enhanced activity of the partial oxidation reaction path.A flow-cell electrolyzer equipped with the AuCu anodic catalyst achieves the steady production of hydrogen and acetic acid simultaneously in both high selectivity(>90%),demonstrating the potential scalable application for green hydrogen production with low energy consumption and high profitability.

关键词： selective ethanol electrooxidation gold alloy catalyst electrochemical-coupled hydrogen production market assessment interfacial water activation

ETHANOL OXIDATION TO ACETALDEHYDE OVER Ag-ZSM-5 ZEOLITE

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Journal of Energy Chemistry 1994年第2期 211-218页

作者： LAI Dao-Rong LI Jing-LinHUANG pei-fang wang Ding-YiDepartment of Chemistry, Guangxi University Nanning, Guangxi 530004

A silver-containing ZSM-5 zeolite catalyst was made and used in the oxidation reaction of ethanol to acetaldehyde. The results show that this catalyst has a markedly higher activity for the title reaction, in which a complete conversion can be achieved at 593 K, than the traditional silver catalyst which manifests catalytic activity only over 773 K. The TPD profiles of adsorbed NH3and O2on the new catalyst were recorded and correlated to the catalytic behavior.

关键词： Ag ETHANOL OXIDATION TO ACETALDEHYDE OVER Ag-ZSM-5 ZEOLITE