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Variations in the effective and bankfull discharge for suspended sediment transport due to dam construction

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Frontiers of Earth Science 2022年第2期16卷 446-464页

作者： fan CHEN Li CHEN wei ZHANG jing YUAN Kanghe ZHANG State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China Changjiang Institute of Survey PlanningDesign and ResearchWuhan 430010China Bureau of Hydrology Changjiang Water Resources CommissionWuhan 430010China

A varied class method is applied to calculate the effective discharges and their variations after the Three Gorges Dam(TGD)construction based on the mean daily flow discharge and suspended sediment concentration field data from 1981 to 2016.For comparison,the bankfull discharges are also determined according to the cross-section profiles and flow discharge-stage relations.Our results show that a bimodal effective discharge curve usually exists at the fixed sites,which generates two effective discharges(Q_(e1) and Q_(e2))within the moderate flow range.Under the quasi-equilibrium circumstances of the pre-dam period,effective discharges are closely related to the mean annual runoff,with a narrow range of regional variations in occurrence frequency.Our analyses draw the conclusion that the relatively higher unsaturation degrees of the pre-dam effective discharges caused by dam interception and riverbed coarsening are the primary cause of the increase in effective discharges from Yichang to Shashi,while the more frequent low and medium discharges due to flow regulation drive the decrease in effective discharges from Jianli to Datong.The slightly elevated flood levels and descending bankfull levels collaboratively result in the decrease of bankfull discharges from Yichang to Shashi,while the lowered bed elevation causes the increase in bankfull discharges from Luoshan to Datong.Overall,the bankfull discharge in the Middle and Lower Yangtze River is larger than effective discharge and approaches the 1.5-year recurrence interval discharge.

关键词： effective discharge bankfull discharge unsaturation degree flow-sediment regimes Middle and Lower Yangtze River Three Gorges Dam

Catalytic decomposition of methane to produce hydrogen:A review

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Journal of Energy Chemistry 2021年第7期30卷 415-430页

作者： Zeyu fan wei Weng jing Zhou Dong Gu wei Xiao School of Resource and Environmental Sciences Hubei International Scientiﬁc and Technological Cooperation Base of Sustainable Resource and EnergyWuhan UniversityWuhan 430072HubeiChina College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power SourcesWuhan UniversityWuhan 430072HubeiChina The Institute for Advanced Studies Wuhan UniversityWuhan 430072HubeiChina

The increasing demands of hydrogen and the recent discovery of large reserves of methane have prompted the conversion of methane to hydrogen.The challenges raised by intensive CO_(2) emission from the traditional conversion of methane have provoked emission-free hydrogen production from methane.The catalytic decomposition of methane(CDM) to produce hydrogen and advanced carbon hence comes into consideration due to the short process and environmental benignity.Although many researchers have made considerable progress in CDM research on the laboratory scale,CDM is still in its infancy in industrialization.The history of its development,fundamental mechanisms,and recent research progress in catalysts and catalytic systems are herein highlighted.The problems of catalytic interface degradation are reviewed,focusing on deactivation from coke deposition in the CDM process.The introduction of a liquid phase interface which can in-situ remove carbon products provides a new strategy for this process.Furthermore,the challenges and prospects for future research into novel CDM catalysts or catalyst systems are included.

关键词： Hydrogen production Methane decomposition Metal-based catalysts Carbon-based catalysts Liquid catalyst

Reading comprehension based on visualization of eye tracking and EEG data

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Science China(Information Sciences) 2020年第11期63卷 276-289页

作者： Shiwei CHENG Yilin HU jing fan Qianjing wei School of Computer Science and Technology Zhejiang University of Technology

Using eye tracking technology can help us understand reading behavior. Furthermore, sharing the teacher’s eye tracking features resulted in improving the students’ comprehension of the same reading material [1]. On ... 详细信息

关键词： N/A null no key words eye tracking EEG

Highly flexible and compressible polyimide/silica aerogels with integrated double network for thermal insulation and fre-retardancy

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Journal of Materials Science & Technology 2022年第10期105卷 194-202页

作者： jing Tian Yi Yang Tiantian Xue Guojie Chao wei fan Tianxi Liu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China

The materials with thermal insulating and fre-retardant properties are highly demanded for architectures to improve the energy efficiency.The applications of conventional inorganic insulating materials such as silica aerogels are restricted by their mechanical fragility and organic insulating materials are either easily ignitable or exhibit unsatisfactory thermal insulation performance.Here,we report an organic/inorganic composite aerogel with integrated double network structure,in which silica constituent homogeneously distribute in the anisotropic polyimide nanofber aerogel matrix and strong interfacial effect is formed between two components.The integrated binary network endows the polyimide/silica composite aerogels with outstanding compressibility and flexibility even with a high inorganic content of 60%,which can withstand 500 cyclic fatigue tests at a compressive strain of 50%in the radial direction.The resulting composite aerogel exhibits a combination of outstanding insulating performance with a low thermal conductivity(21.2 mW m^(-1)K^(-1))and excellent resistance to a 1200℃flame without disintegration.The high-performance polyimide/silica aerogels can decrease the risk brought by the collapse of reinforced concrete structures in a fre,demonstrating great potential as efficient building materials.

关键词： Polyimide Silica Aerogel Thermal insulation Fire-retardancy

Hardening effects of sheared precipitates on {1121} twinning in magnesium alloys

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Journal of Magnesium and Alloys 2023年第2期11卷 580-591页

作者： jing Tang Wentao Jiang Qingyuan Wang Xiaobao Tian Dean wei Haidong fan Department of Mechanics Sichuan UniversityChengdu 610065China School of Mechanics and Engineering Southwest Jiaotong UniversityChengdu 610031China

The interactions between a plate-like precipitate and two twin boundaries(TBs)({1012},{1121}) in magnesium alloys are studied using molecular dynamics(MD) simulations. The precipitate is not sheared by {1012} TB, but sheared by {1121} TB. Shearing on the(110) plane is the predominant deformation mode in the sheared precipitate. Then, the blocking effects of precipitates with different sizes are studied for {1121} twinning. All the precipitates show a blocking effect on {1121} twinning although they are sheared, while the blocking effects of precipitates with different sizes are different. The blocking effect increases significantly with the increasing precipitate length(in-plane size along TB) and thickness, whereas changes weakly as the precipitate width changes. Based on the revealed interaction mechanisms, a critical twin shear is calculated theoretically by the Eshelby solutions to determine which TB is able to shear the precipitate. In addition, an analytical hardening model of sheared precipitates is proposed by analyzing the force equilibrium during TB-precipitate interactions. This model indicates that the blocking effect depends solely on the area fraction of the precipitate cross-section, and shows good agreement with the current MD simulations. Finally, the blocking effects of plate-like precipitates on the {1012} twinning(non-sheared precipitate), {1121} twinning(sheared precipitate) and basal dislocations(non-sheared precipitate) are compared together. Results show that the blocking effect on {1121} twinning is stronger than that on {1012} twinning, while the effect on basal dislocations is weakest. The precipitate-TB interaction mechanisms and precipitation hardening models revealed in this work are of great significance for improving the mechanical property of magnesium alloys by designing microstructure.

关键词： Magnesium alloys Precipitate-twin boundary interactions Sheared precipitate Precipitation hardening model Molecular dynamics simulations

Morphological and biochemical characteristics associated with autophagy in gastrointestinal diseases

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World Journal of Gastroenterology 2024年第11期30卷 1524-1532页

作者： Yi-fan Chang Jia-jing Li Tao Liu Chong-Qing wei Li-wei Ma Vladimir N Nikolenko wei-Long Chang Department of Gastrointestinal Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Department of Pathology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Department of Clinical Laboratory The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Department of Human Anatomy and Histology I.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow 119991Russia

Autophagy is a cellular catabolic process characterized by the formation of double-membrane autophagosomes.Transmission electron microscopy is the most rigorous method to clearly visualize autophagic engulfment and degradation.A large number of studies have shown that autophagy is closely related to the digestion,secretion,and regeneration of gastrointestinal(GI)cells.However,the role of autophagy in GI diseases remains controversial.This article focuses on the morphological and biochemical characteristics of autophagy in GI diseases,in order to provide new ideas for their diagnosis and treatment.

关键词： Autophagy Morphological study Biochemical characteristics Subcellular structure Transmission electron microscopy Gastrointestinal diseases

Research progress in the treatment of diabetic foot ulcer with platelet rich plasma

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Journal of Hainan Medical University 2020年第7期26卷 68-71页

作者： Wei-Jing Fan Guo-Bin Liu Shuguang Hospital Affiliated to Shanghai University of traditional Chinese medicine Shanghai200032

Diabetic foot ulcer,as a common complication of diabetes,is a difficult problem in clinical practice.As a new therapeutic method,platelet rich plasma has the functions of anti-inflammatory,bacteriostasis,microcirculation reconstruction,cell proliferation and differentiation,cell apoptosis reduction,peripheral nerve repair and so on.It can promote tissue repair and ulcer healing at every stage of diabetic foot ulcer.This article reviews the preparation of platelet rich plasma,the mechanism of action,the treatment of diabetic foot ulcer,the existing problems and the future development.

关键词： Platelet rich plasma Diabetic foot ulcer Skin Tendon Bone

Evidence for two types of Aquilegia ecalcarata and its implications for adaptation to new environments

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Plant Diversity 2022年第2期44卷 153-162页

作者： Lei Huang fang-Dong Geng jing-jing fan wei Zhai Cheng Xue Xiao-Hui Zhang Yi Ren Ju-Qing Kang National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China College of Life SciencesShaanxi Normal UniversityXi'anShaanxi 710119China

Spurs have played an important role in the radiation of the genus Aquilegia,but little is known about how the spurless state arose in A.ecalcarata.Here we aim to characterize the genetic divergence within A.ecalcarata and gain insights into the origin of this species.A total of 19 populations from A.ecalcarata and 23 populations from three of its closest relatives(Aquilegia kansuensis,Aquilegia rockii and Aquilegia yabeana)were sampled in this study.We sequenced fifteen nuclear gene fragments across the genome and three chloroplast loci to conduct phylogenetic,PCoA and STRUCTURE analyses.Our analyses indicate that A.ecalcarata may not be monophyletic and can be divided into two distinct lineages(A.ecalcarataⅠand A.ecalcarataⅡ).A.ecalcarataⅠis genetically close to A.kansuensis,whereas A.ecalcarataⅡis close to A.rockii.Isolation-with-migration analysis suggested that historical gene flow was low between A.ecalcarataⅠand A.rockii,as well as between A.ecalcarataⅡand A.kansuensis.The two distinct lineages of A.ecalcarata show significant divergence in 13 floral traits and also have distinct distributions.In addition,both A.ecalcarataⅠandⅡare adapted to a stony environment that differs from that of their closest relatives,indicating a habitat shift may have driven new adaptations.Our findings enrich the understanding of how floral evolution contributes to species diversification.

关键词： Aquilegia ecalcarata Phylogeny Population structure Gene flow Spur loss

Dispersion features of pollutants in a compound channel with vegetated floodplains

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Journal of Hydrodynamics 2022年第6期34卷 1095-1105页

作者： Yan-fang Zhao jing-jing fan wei-jie Wang Han-qing Zhao Fei Dong Zhen Han Shi-yan Wang School of Water Conservancy and Hydroelectric Power Hebei University of EngineeringHandan056038China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing100038China China Three Gorges Corporation Wuhan430010China National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Nanjing210024China

The planting of the vegetation on the floodplain helps the ecological restoration,which is the main form of the river’s ecological corridor.Therefore,the current research of the river dynamics focuses on the water movement under a compound channel with the vegetated floodplains.Two simulated vegetation species are selected in this paper for the flume simulation experiments of the floodplain vegetation,and the compound channel is divided into three subregions in the transverse direction.The Navier-Stokes equation and the eddy viscosity theory are applied to obtain the transverse distribution of the depth-averaged velocity and the results agree well with the experimental data.This paper proposes a new method based on the analytical solution of the flow velocity distribution to calculate the average flow velocity in each section.Calculation results can effectively simulate the average flow velocity of the measured sections.The description of the pollutant transport processes in a moving stream requires a refined determination of the dispersion coefficients in the compound channel.The process of the pollutant concentrations in each zone and the reasons for their occurrence are elucidated on the basis of the experimental results.Simultaneously,the measured values of the longitudinal dispersion coefficients are obtained by the“routing procedure,”and a two-zone model of the pollutant dispersion is constructed on the basis of the hydrodynamic study.The prediction method for the longitudinal dispersion coefficients is also presented.Applying the predicted and measured section average flow velocities to the two-zone model to predict the longitudinal dispersion coefficient,and the average relative errors are only 4.17%,7.15%,respectively.This result indicates that the two-zone model can effectively predict the longitudinal dispersion coefficients.The calculation methods for the longitudinal dispersion coefficients from—various studies are compared.The results reveal that the predicted values of these calculation methods are

关键词： Compound channel floodplain vegetation velocity distribution pollutant transport dispersion coefficient