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Journal of Ocean University of China 2024年第1期23卷 23-32页

作者： WU De’an LI Xin WANG Yigang College of harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China Tianjin Research Institute For Water Transport engineering Tianjin 300456China

To study the stratified stability of a water column in the North Passage of the Yangtze river Estuary,a numerical model of the hydrodynamics of this estuary is established using the EFDC model.On the basis of EFDC results,this paper derives and pro-vides the discriminative index of water body stability caused by salinity and analyzes the along-range variation in water body strati-fication stability in the North Passage of the Yangtze river Estuary and the periodic variation at a key location(bend area)based on the simulation results of the numerical model.This work shows that the water body in the bend area varies between mixed and strati-fied types,and the vertical average flow velocity has a good negative correlation with the differential velocity between the surface and bottom layers of the water body.The model simulation results validate the formulae for the stratified stability discriminant during spring tides.

关键词： Yangtze Estuary North Passage EFDC model stratification stability salinity distribution

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Fundamentals and progress of the manifold method based on independent covers

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Science China(Technological Sciences) 2024年第4期67卷 966-991页

作者： SU HaiDong LIN ShaoZhong XIE ZhiQiang GONG YaQi QI YongFeng Material and engineering Structure department Yangtze River Scientific Research InstituteWuhan 430010China Research Center of Water engineering Safety and Disaster Prevention of Ministry of Water Resources Wuhan 430010China

Aiming to solve mesh generation,computational stability,accuracy control,and other problems encountered with existing numerical methods,such as the finite element method and the finite volume method,a new numerical computational method for continuum mechanics,namely the manifold method based on independent covers(MMIC),is proposed based on the concept of mathematical manifolds,to form partitioned series solutions of partial differential equations.As partitions,the cover meshes have the characteristics of arbitrary shape,arbitrary connection,and arbitrary refinement.They are expected to fundamentally solve the mesh generation problem and can also simulate the precise geometric boundaries of the CAD model and strictly impose boundary conditions.In the selection of series solutions,local analytical solutions(such as series solutions at crack tips and series solutions in infinite domains)or proper forms of complete series can be used to reflect the local or global characteristics of the physical field to accelerate convergence.Various applications are presented.A new method of beam,plate,and shell analysis is proposed.The deformation characteristics of beams,plates,and shells are simulated with polynomial series of suitable forms,and the analysis of curved beams and shells with accurate geometric representation is realized.For the static elastic analysis of two-dimensional structures,a mesh splitting algorithm is proposed,and h-p version adaptive analysis is carried out with error estimation.Thus,automatic computation integrated with CAD is attempted.Adaptive analysis is also attempted for the solution of differential equations of fluids.For the one-dimensional convection-diffusion equation and Burgers equation,calculation results with high precision are obtained in strong convection and shock wave simulations,avoiding nonphysical oscillations.And solving the two-dimensional incompressible Navier-Stokes equation is also attempted.The series solution formula is used to obtain the physical quantity of interest of the m

关键词： series solutions mesh generation adaptive analysis fixed meshes numerical manifold method

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Amorphous electrocatalysts for urea oxidation reaction

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Progress in Natural Science:Materials International 2024年第2期34卷 362-375页

作者： Fenghui Guo Dongle Cheng Qian Chen Hao Liu Zhiliang Wu Ning Han Bing-Jie Ni Zhijie Chen School of Materials Science and Technology China University of Geosciences Shenzhen Academy of Metrology and Quality Inspection Centre for Technology in Water and Wastewater School of Civil and Environmental Engineering University of Technology Sydney College of Safety and Environmental engineering Shandong University of Science and Technology Institute of Yellow river Delta Earth Surface Processes and Ecological Integrity Shandong University of Science and Technology Discipline of Chemical engineering Western Australian School of Mines: Minerals Energy and Chemical Engineering Curtin University department of Materials engineering School of Civil and Environmental engineering The University of New South Wales

Electrochemical urea oxidation reaction(UOR) is a promising alternative to oxygen evolution reaction(OER) for realizing energy-saving hydrogen production. Developing efficient electrocatalysts for UOR becomes a central challenge. Recently, amorphous materials have been extensively used as UOR catalysts because of their numerous defective sites and flexible electronic properties. In this review, recent advancements in the development of amorphous UOR electrocatalysts are analyzed. The UOR mechanism is discussed, and the design of amorphous catalysts is then analyzed. The main catalyst design strategies are illustrated, including nanostructure control,heteroatom doping, composition regulation, and heterostructure construction. Also, electrocatalysts' structureperformance correlation is interpreted. Perspectives in this field are proposed for guiding future studies on the development of high-performance amorphous catalysts towards energy sustainability.

关键词： Catalyst design Component regulation Heteroatom doping Heterostructures Hydrogen energy

Long-term impact of artificial intelligence on colorectal adenoma detection in high-risk colonoscopy

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World Journal of Gastrointestinal Endoscopy 2024年第6期16卷 335-342页

作者： Kenneth W Chow Matthew T Bell Nicholas Cumpian Maryanne Amour Ryan H Hsu Viktor E Eysselein Neetika Srivastava Michael W Fleischman Sofiya Reicher department of Medicine Harbor-UCLA Medical CenterTorranceCA 90502United States department of Bioengineering Jacobs School of EngineeringUniversity of CaliforniaSan DiegoLa JollaCA 92093United States department of Gastroenterology Harbor-UCLA Medical CenterTorranceCA 90502United States

BACKGROUND Improved adenoma detection rate(ADR)has been demonstrated with artificial intelligence(AI)-assisted colonoscopy.However,data on the real-world appli-cation of AI and its effect on colorectal cancer(CRC)screening outcomes is limited.AIM To analyze the long-term impact of AI on a diverse at-risk patient population undergoing diagnostic colonoscopy for positive CRC screening tests or sympt-oms.METHODS AI software(GI Genius,Medtronic)was implemented into the standard proced-ure protocol in November 2022.Data was collected on patient demographics,procedure indication,polyp size,location,and pathology.CRC screening outcomes were evaluated before and at different intervals after AI introduction with one year of follow-up.RESULTS We evaluated 1008 colonoscopies(278 pre-AI,255 early post-AI,285 established post-AI,and 190 late post-AI).The ADR was 38.1%pre-AI,42.0%early post-AI(P=0.77),40.0%established post-AI(P=0.44),and 39.5%late post-AI(P=0.77).There were no significant differences in polyp detection rate(PDR,baseline 59.7%),advanced ADR(baseline 16.2%),and non-neoplastic PDR(baseline 30.0%)before and after AI introduction.CONCLUSION In patients with an increased pre-test probability of having an abnormal colonoscopy,the current generation of AI did not yield enhanced CRC screening metrics over high-quality colonoscopy.Although the potential of AI in colonoscopy is undisputed,current AI technology may not universally elevate screening metrics across all situations and patient populations.Future studies that analyze different AI systems across various patient populations are needed to determine the most effective role of AI in optimizing CRC screening in clinical practice.

关键词： Artificial intelligence Colonoscopy Adenoma detection rate Screening Colorectal adenoma

Failure transition of shear-to-dilation band of rock salt under triaxial stresses

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Journal of Rock Mechanics and Geotechnical engineering 2024年第1期16卷 56-64页

作者： Jianfeng Liu Xiaosong Qiu Jianxiong Yang Chao Liang Jingjing Dai Yu Bian State Key Laboratory of Hydraulics and Mountain river engineering Sichuan UniversityChengdu610065China CNPC Key Laboratory of Oil and Gas Underground Storage engineering Langfang065007China College of Water Resource and Hydropower Sichuan UniversityChengdu610065China

Great potential of underground gas/energy storage in salt caverns seems to be a promising solution to support renewable energy.In the underground storage method,the operating cycle unfortunately may reach up to daily or even hourly,which generates complicated pressures on the salt cavern.Furthermore,the mechanical behavior of rock salt may change and present distinct failure characteristics under different stress states,which affects the performance of salt cavern during the time period of full service.To reproduce a similar loading condition on the cavern surrounding rock mass,the cyclic triaxial loading/unloading tests are performed on the rock salt to explore the mechanical transition behavior and failure characteristics under different confinement.Experimental results show that the rock salt samples pre-sent a diffused shear failure band with significant bulges at certain locations in low confining pressure conditions(e.g.5 MPa,10 MPa and 15 MPa),which is closely related to crystal misorientation and grain boundary sliding.Under the elevated confinement(e.g.20 MPa,30 MPa and 40 MPa),the dilation band dominates the failure mechanism,where the large-size halite crystals are crushed to be smaller size and new pores are developing.The failure transition mechanism revealed in the paper provides additional insight into the mechanical performance of salt caverns influenced by complicated stress states.

关键词： Rock salt Cyclic mechanical loading Shear band Dilation band Underground gas storage(UGS)

Afterglow Nanoprobes for In-vitro Background-free Biomarker Analysis

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Chemical Research in Chinese Universities 2024年第2期40卷 213-224页

作者： ZHENG Ting WANG Ying LI Xianming LI Chenghui WU Peng Analytical&Testing Centre State Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengdu610064P.R.China School of Chemistry and Chemical engineering Henan Normal UniversityXinxiang453007P.R.China department of Rheumatology and Immunology West China HospitalSichuan UniversityChengdu610064P.R.China

Accurate detection of biomarkers is essential for disease diagnosis.Although the highly sensitive fluorescence probes are feasible for the above goal,it is typically interfered by the auto-fluorescence and light scattering of the biological samples.Photochemical afterglow system(consisting of photosensitizer,afterglow substrate and emitter)based on cascade photochemical reactions exhibits long-lived luminescence(seconds to hours),thus avoiding background interference.With the assistance of polymers,such as polystyrene microspheres,the photochemical afterglow systems have been transformed into homogeneous and water-soluble nanoparticles,and used for in-vitro biomarker analysis.Here,we summarized the principle,preparation and applications of these afterglow nanoparticles,and evaluated their performance in clinical sample testing by comparing with other nanoparticle-based methods.Finally,several problems and possible solutions of afterglow nanoparticle-based methods in biomarker determination were also mentioned.

关键词： Photochemical afterglow In-vitro analysis Background-free detection Biomarker

Sacrificial piles as a countermeasure against local scour around underwater pipelines

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Water Science and engineering 2024年第2期17卷 187-196页

作者： Forough Raeisi Seyed Mohammad Ali Zomorodiann Masih Zolghadr Hazi Mohammad Azamathulla department of Water engineering Shiraz UniversityShiraz ***Iran department of Water Sciences engineering Jahrom UniversityJahrom ***Iran department of Civil and Environmental engineering The University of the West IndiesSt.Augustine CampusTrinidad 331310Republic of Trinidad and Tobago

Local scour around pipelines crossing rivers or in marine environments is a significant concern.It can lead to failure of the pipelines resulting in environmental side effects and economic losses.This study developed an experimental method to reduce local scour around pipelines with a steady flow of clear water by installing cylindrical and cubical sacrificial piles.Three sizes of sacrificial piles were examined in a linear arrangement.Sacrificial piles were installed on the upstream side of the pipeline at three distances.Maximum scour depth reduction rates below the pipeline were computed.The results showed that sacrificial piles could protect a pipeline from local scour.A portion of scoured sediment around the sacrificial piles was deposited beneath the pipeline.This sediment accumulation reduced the scour depth beneath the pipeline.Analysis of the experimental results demonstrated that the size of piles(d),the spacing between piles,and the distance between the pipe and piles(Xp)were the variables that reduced the maximum scour beneath the pipeline with a diameter of D.For the piles with d=0.40D and 0.64D,X_(p)=4OD was the optimal distance to install a group of piles,and cubical piles could mitigate scour more effectively than cylindrical piles under similar conditions.For the piles with d=D,the greatest reduction in scour depth was achieved at X_(p)=50D with any desired spacings between piles,and cylindrical piles in this dimension could protect the pipeline against scour more effectively than cubical piles.

关键词： Clear water river crossing pipeline Local scour Self-burial process Sediment transport

Advancement of metal(loid) research on farmland

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Frontiers of Agricultural Science and engineering 2024年第3期11卷 442-467页

作者： Qiang ZHENG Chenchen WEI Yanbing CHI Peiling YANG College of Water Resources and Civil engineering China Agricultural University Agricultural Water Conservancy department Changjiang River Scientific Research Institute Zhejiang University of Water Resources and Electric Power

Metal(loid) pollution has emerged as a pressing environmental issue in agriculture, garnering extensive public attention. Metal(loid)s are potentially toxic substances that infiltrate the soil through diverse pathways, leading to food chain contamination via plant uptake and subsequent animal exposure.This poses a serious threat to environmental quality, food security, and human health. Hence, the remediation of metal(loid)-contaminated agricultural soil is an urgent concern demanding immediate attention. Presently, the majority of research papers concentrate on established, isolated remediation technologies, often overlooking comprehensive field management approaches.It is imperative to provide a comprehensive summary of remediation technologies and identify future development directions. This review aims to comprehensively summarize a range of soil remediation and enhancement technologies, incorporating insights from multiple disciplines including physics,chemistry, biology, and their interdisciplinary intersections. The review examines the mechanisms of action, suitable scenarios, advantages,disadvantages, and benefits associated with each remediation technology.Particularly relevant is the examination of metal(loid) sources, as well as the mechanisms behind both established and innovative, efficient remediation and enhancement technologies. Additionally, the future evolution of remediation technologies are considered with the aim of offering a scientific research foundation and inspiration to fellow researchers. This is intended to facilitate the advancement of remediation technologies and establish a robust foundation for sustainable development of soil.

关键词： Metal(loid) pollution metal(loid) remediation metal(loid) sources soil

Monitoring and evaluation of the water quality of the Lower Neches river, Texas, USA

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Water Science and engineering 2024年第1期17卷 21-32页

作者： Qin Qian Mengjie He Frank Sun Xinyu Liu department of Civil and Environmental engineering Lamar UniversityBeaumontTX 77710USA department of Industry engineering Lamar UniversityBeaumontTX 77710USA department of Computer Science Lamar UniversityBeaumontTX 77710USA

Increasing bacteria levels in the Lower Neches river caused by Hurricane Harvey has been of a serious concern.This study is to analyze the historical water sampling measurements and real-time water quality data collected with wireless sensors to monitor and evaluate water quality under different hydrological and hydraulic conditions.The statistical and Pearson correlation analysis on historical water samples determines that alkalinity,chloride,hardness,conductivity,and pH are highly correlated,and they decrease with increasing flow rate due to dilution.The flow rate has positive correlations with Escherichia coli,total suspended solids,and turbidity,which demonstrates that runoff is one of the causes of the elevated bacteria and sediment loadings in the river.The correlation between E.coli and turbidity indicates that turbidity greater than 45 nephelometric turbidity units in the Neches river can serve as a proxy for E.coli to indicate the bacterial outbreak.A series of statistical tools and an innovative two-layer data smoothing filter are developed to detect outliers,fill missing values,and filter spikes of the sensor measurements.The correlation analysis on the sensor data illustrates that the elevated sediment/bacteria/algae in the river is either caused by the first flush rain and heavy rain events in December to March or practices of land use and land cover.Therefore,utilizing sensor measurements along with rainfall and discharge data is recommended to monitor and evaluate water quality,then in turn to provide early alerts on water resources management decisions.

关键词： Water quality Pearson correlation analysis Lower Neches river YSI wireless sensors Non-point pollution

Modularized and Parametric Modeling Technology for Finite Element Simulations of Underground engineering under Complicated Geological Conditions

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Computer Modeling in engineering & Sciences 2024年第7期140卷 621-645页

作者： Jiaqi Wu Li Zhuo Jianliang Pei Yao Li Hongqiang Xie Jiaming Wu Huaizhong Liu State Key Laboratory of Hydraulics and Mountain river engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China Research Institute of Testing and Inspection Sinohydro Bureau 7 Co.Ltd.Chengdu610213China

The surrounding geological conditions and supporting structures of underground engineering are often updated during construction,and these updates require repeated numerical modeling.To improve the numerical modeling efficiency of underground engineering,a modularized and parametric modeling cloud server is developed by using Python codes.The basic framework of the cloud server is as follows:input the modeling parameters into the web platform,implement Rhino software and FLAC3D software to model and run simulations in the cloud server,and return the simulation results to the web platform.The modeling program can automatically generate instructions that can run the modeling process in Rhino based on the input modeling parameters.The main modules of the modeling program include modeling the 3D geological structures,the underground engineering structures,and the supporting structures as well as meshing the geometric models.In particular,various cross-sections of underground caverns are crafted as parametricmodules in themodeling program.Themodularized and parametric modeling program is used for a finite element simulation of the underground powerhouse of the Shuangjiangkou Hydropower Station.This complicatedmodel is rapidly generated for the simulation,and the simulation results are reasonable.Thus,this modularized and parametric modeling program is applicable for three-dimensional finite element simulations and analyses.

关键词： Underground engineering modularized and parametric modeling finite element method complex geological structure cloud modeling