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Hydrodynamic characteristics and particle tracking of 90° lateral intakes at an inclined river slope

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Water Science and Engineering 2024年第2期17卷 197-208页

作者： Wei He Si-yuan feng Jian Zhang Hong-wu Tang Yang Xiao sheng Chen Chun-sheng Liu College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China State Key Laboratory of Hydrology Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China Collaborative Innovation Center on Water Safety and Water Science Hohai UniversityNanjing 210098China

Lateral intakes are common in rivers.The pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division width.The hydraulic characteristics of lateral withdrawal from inclined river slopes at different intake elevations should be investigated.Meanwhile,the division width exhibits significant vertical non-uniformity at an inclined river slope,which should be clarified.Hence,a three-dimensional(3-D)hydrodynamic and particle-tracking model was developed with the Open Source Field Operation and Manipulation(Open FOAM),and the model was validated with physical model tests for 90°lateral withdrawal from an inclined side bank.The flow fields,withdrawal sources,and division widths were investigated with different intake bottom elevations,withdrawal discharges,and main channel velocities.This study showed that under inclined side bank conditions,water entered the intake at an oblique angle,causing significant 3-D spiral flows in the intake rather than two-dimensional closed recirculation.A lower withdrawal discharge,a lower bottom elevation of the intake,or a higher main channel velocity could further strengthen this phenomenon.The average division width and turbulent kinetic energy were smaller under inclined side bank conditions than under vertical bank conditions.With a low intake bottom elevation,a low withdrawal discharge,or a high main channel velocity,the sources of lateral withdrawal were in similar ranges near the local inclined bank in the vertical direction.Under inclined slope conditions,sediment deposition near the intake entrance could be reduced,compared to that under vertical slope conditions.The results provide hydrodynamic and sediment references for engineering designs for natural rivers with inclined terrains.

关键词： Lateral withdrawal Hydrodynamic characteristics Particle tracking Inclined river slope Bottom elevation of intake OpenFOAM

Relationships among Sedentary Time,Electronic Product Addiction,and Depression in Adolescents during the COVID-19 Epidemic:A Cross-Lagged Study

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International Journal of Mental Health Promotion 2024年第3期26卷 221-228页

作者： feng sheng Chen Kong Chao Li Teaching Department of Sports Qufu Normal UniversityQufu273165China Teaching Department of Sports Shandong Management UniversityJinan250100China General Education Center Weifang Vocational CollegeWeifang262737China

Objective:This study was conducted to explore the relationships among sedentary behavior(SB),electronic product addiction(EPA),and depression(D)in adolescents during the COVID-19 epidemic.Methods:A total of 604 adolescents(including 309 girls and 295 boys aged 12-18)were selected from Qufu City,Shandong Province,China for three rounds of investigation.The model was constructed using AMOS 23.0 software,and cross-lagged analysis was conducted.Results:SB at T1 can significantly positively predict SB and EPA at T2(p<0.05).EPA at T1 can significantly positively predict SB and D at T2(p<0.05).Physical activity level and SB at T2 can significantly predict SB and EPA at T3(p<0.05).EPA at T2 can significantly predict SB,EPA,and D at T3(p<0.05).Conclusions:SB and EPA are predictive factors for D.Moreover,SB can significantly positively predict D and indirectly predict D through the mediating effect of EPA.

关键词： COVID-19 electronic product addiction depression sedentary behavior

Microstructure,wear and friction behavior of CoCrAITaY-xCNTs composite coatings deposited by laser-induction hybrid cladding

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Rare Metals 2024年第4期43卷 1815-1827页

作者： sheng-feng Zhou Yu Long Yan-Liang Yi Cheng Deng Lian-Xi Hu Institute of Advanced Wear & Corrosion Resistant and Functional Materials Jinan University Wuhan National Laboratory for Optoelectronics (WNLO) Huazhong University of Science and Technology MOE Key Laboratory of New Processing Technology for NonFerrous Metals and Materials Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured Materials Guangxi University School of Mechatronics Engineering Guangdong Polytechnic Normal University School of Materials Science and Engineering Harbin Institute of Technology

To improve the wear performance of CoCrAlYTa coating,part of the carbon nanotubes（CNTs）chemically reacted with Ta to form reinforcement phase（TaC）,while the other CNTs were retained as lubrication phase.Subsequently,the CoCrAlYTa-xCNTs（x=0,1,2,and 4;wt%） composite coatings were prepared by laserinduction hybrid cladding（LIHC）,and the microstructure and wear resistance of coatings were systematically analyzed.Results show that the coatings are mainly composed of TaC,y-（Co,Cr） and β-（Co,Cr）Al.As the CNTs content increases from 0 wt% to 4 wt%,the volume fraction of TaC increases from 13.11 vol% to 16.12 vol%.Meanwhile,the nano-hardness of γ-（Co,Cr） and β-（Co,Cr）Al are improved from 7.49 and 9.72 to 9.36 and 11.19 GPa,respectively.As a result,the microhardness of coating increases from HV536.25 to HV 738.16,the wear rate decreases from32.4 × 10-3to 6.1 × 10-3mg·m-1,and the average friction coefficient decreases from 0.55 to 0.44.The good wear performance of the coating is attributed to the formation of TaC and the existence of remained CNTs lubricant film.

关键词： Carbon nanotube MCrAlY coating Friction and wear performance Laser-induction hybrid cladding

Recent advances in bioinspired vision systems with curved imaging structures

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Rare Metals 2024年第4期43卷 1407-1434页

作者： Ze-Ping He Xun Han Wen-Qiang Wu Zhang-sheng Xu Cao-feng Pan CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-Nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of Sciences School of Nanoscience and Technology University of Chinese Academy of Sciences ZJU-Hangzhou Global Scientific and Technological Innovation Center School of Micro-Nano ElectronicsZhejiang University Institute of Microscale Optoelectronics Shenzhen University

Limited by the planar imaging structure,the commercial camera needs to introduce additional optical elements to compensate for the curved focal plane to match the planar image sensor.This results in a complex and bulky structure.In contrast,biological eyes possess a simple and compact structure due to their curved imaging structure that can directly match with the curved focal plane.Inspired by the structures and functions of biological eyes,curved vision systems not only improve the image quality,but also offer a variety of advanced functions.Here,we review the recent advances in bioinspired vision systems with curved imaging structures.Specifically,we focus on their applications in implementing different functions of biological eyes,as well as the emerging curved neuromorphic imaging systems that incorporate bioinspired optical and neuromorphic processing technologies.In addition,the challenges and opportunities of bioinspired curved imaging systems are also discussed.

关键词： Bioinspired Curved vision system Compound eye Chambered eye Neuromorphic

Effects of data smoothing and recurrent neural network(RNN)algorithms for real-time forecasting of tunnel boring machine(TBM)performance

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1538-1551页

作者： feng Shan Xuzhen He Danial Jahed Armaghani Daichao sheng School of Civil and Environmental Engineering University of Technology SydneyNSW2007Australia

Tunnel boring machines(TBMs)have been widely utilised in tunnel construction due to their high efficiency and reliability.Accurately predicting TBM performance can improve project time management,cost control,and risk management.This study aims to use deep learning to develop real-time models for predicting the penetration rate(PR).The models are built using data from the Changsha metro project,and their performances are evaluated using unseen data from the Zhengzhou Metro project.In one-step forecast,the predicted penetration rate follows the trend of the measured penetration rate in both training and testing.The autoregressive integrated moving average(ARIMA)model is compared with the recurrent neural network(RNN)model.The results show that univariate models,which only consider historical penetration rate itself,perform better than multivariate models that take into account multiple geological and operational parameters(GEO and OP).Next,an RNN variant combining time series of penetration rate with the last-step geological and operational parameters is developed,and it performs better than other models.A sensitivity analysis shows that the penetration rate is the most important parameter,while other parameters have a smaller impact on time series forecasting.It is also found that smoothed data are easier to predict with high accuracy.Nevertheless,over-simplified data can lose real characteristics in time series.In conclusion,the RNN variant can accurately predict the next-step penetration rate,and data smoothing is crucial in time series forecasting.This study provides practical guidance for TBM performance forecasting in practical engineering.

关键词： Tunnel boring machine(TBM) Penetration rate(PR) Time series forecasting Recurrent neural network(RNN)

Constant charge method or constant potential method:Which is better for molecular modeling of electrical double layers?

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Journal of Energy Chemistry 2024年第7期94卷 54-60页

作者： Liang Zeng Xi Tan Xiangyu Ji Shiqi Li Jinkai Zhang Jiaxing Peng sheng Bi Guang feng State Key Laboratory of Coal Combustion Schoolof Energy and PowerEngineeringHuazhong Universityof Science and Technology(HUST)Wuhan 430074HubeiChina Sorbonne Universite CNRSPhysico-chimie des Electrolytes et Nanosystemes InterfaciauxPHENIXF-75005 ParisFrance

In molecular modeling of electrical double layers(EDLs),the constant charge method(CCM)is prized for its computational efficiency but cannot maintain electrode equipotentiality like the more resourceintensive constant potential method(CPM),potentially leading to inaccuracies.In certain scenarios,CCM can yield results identical to CPM.However,there are no clear guidelines to determine when CCM is sufficient and when CPM is required.Here,we conduct a series of molecular simulations across various electrodes and electrolytes to present a comprehensive comparison between CCM and CPM under different charging modes.Results reveal that CCM approximates CPM effectively in capturing equilibrium EDL and current-driven dynamics in open electrode systems featuring ionic liquids or regular concentration aqueous electrolytes,while CPM is indispensable in scenarios involving organic and highly concentrated aqueous electrolytes,nanoconfinement effects,and voltage-driven dynamics.This work helps to select appropriate methods for modeling EDL systems,prioritizing accuracy while considering computationalefficiency.

关键词： Electrochemical interface Molecular dynamics Electrode polarization modeling Nanoconfinement effect

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HepG2.2.15-derived exosomes facilitate the activation and fibrosis of hepatic stellate cells

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World Journal of Gastroenterology 2024年第19期30卷 2553-2563页

作者： Yang Gao Li Li sheng-Ning Zhang Yuan-Yi Mang Xi-Bing Zhang Shi-Ming feng Department of Hepatobiliary Pancreatic and Vascular Surgery The Affiliated Calmette Hospital of Kunming Medical University and The First Hospital of KunmingKunming 650011Yunnan ProvinceChina

BACKGROUND The role of exosomes derived from HepG2.2.15 cells,which express hepatitis B virus(HBV)-related proteins,in triggering the activation of LX2 liver stellate cells and promoting liver fibrosis and cell proliferation remains elusive.The focus was on comprehending the relationship and influence of differentially expressed microRNAs(DE-miRNAs)within these exosomes.AIM To elucidate the effect of exosomes derived from HepG2.2.15 cells on the activation of hepatic stellate cell(HSC)LX2 and the progression of liver fibrosis.METHODS Exosomes from HepG2.2.15 cells,which express HBV-related proteins,were isolated from parental HepG2 and WRL68 cells.Western blotting was used to confirm the presence of the exosomal marker protein CD9.The activation of HSCs was assessed using oil red staining,whereas DiI staining facilitated the observation of exosomal uptake by LX2 cells.Additionally,we evaluated LX2 cell proliferation and fibrosis marker expression using 5-ethynyl-2′-deoxyuracil staining and western blotting,respectively.DE-miRNAs were analyzed using DESeq2.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways were used to annotate the target genes of DE-miRNAs.RESULTS Exosomes from HepG2.2.15 cells were found to induced activation and enhanced proliferation and fibrosis in LX2 cells.A total of 27 miRNAs were differentially expressed in exosomes from HepG2.2.15 cells.GO analysis indicated that these DE-miRNA target genes were associated with cell differentiation,intracellular signal transduction,negative regulation of apoptosis,extracellular exosomes,and RNA binding.KEGG pathway analysis highlighted ubiquitin-mediated proteolysis,the MAPK signaling pathway,viral carcinogenesis,and the toll-like receptor signaling pathway,among others,as enriched in these targets.CONCLUSION These findings suggest that exosomes from HepG2.2.15 cells play a substantial role in the activation,proliferation,and fibrosis of LX2 cells and that DE-miRNAs within these exosomes contribute to the underlying mechanisms.

关键词： Hepatic stellate cells Liver fibrosis Exosomes Small RNA sequencing HepG2.2.15

Sedimentary architecture of submarine channel-lobe systems under different seafloor topography:Insights from the Rovuma Basin offshore East Africa

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Petroleum Science 2024年第1期21卷 125-142页

作者： Mei Chen sheng-He Wu Rui-feng Wang Jia-Jia Zhang Peng-Fei Xie Min Wang Xiao-feng Wang Ji-Tao Yu Qi-Cong Xiong State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Faculty of Geosciences University of BremenBremen28359Germany MARUM-Center for Marine and Environmental Sciences University of BremenBremen28359Germany Research institute of Petroleum Exploration and Development PetroChinaBeijing10083China School of Geosciences Yangtze UniversityWuhan 100083HubeiChina CNODC Mozambique Ltd. Beijing 100034China

Seafloor topography plays an important role in the evolution of submarine lobes.However,it is still not so clear how the shape of slope affects the three-dimensional(3-D)architecture of submarine lobes.In this study,we analyze the effect of topography factors on different hierarchical lobe architectures that formed during Pliocene to Quaternary in the Rovuma Basin offshore East Africa.We characterize the shape,size and growth pattern of different hierarchical lobe architectures using 3-D seismic data.We find that the relief of the topographic slope determines the location of preferential deposition of lobe complexes and single lobes.When the topography is irregular and presents topographic lows,lobe complexes first infill these depressions.Single lobes are deposited preferentially at positions with higher longitudinal(i.***.across-slope)slope gradients.As the longitudinal slope becomes higher,the aspect ratio of the single lobes increases.Lateral(i.***.along-slope)topography does not seem to have a strong influence on the shape of single lobe,but it seems to affect the overlap of single lobes.When the lateral slope gradient is relatively high,the single lobes tend to have a larger overlap surface.Furthermore,as the average of lateral slope and longitudinal slope gets greater,the width/thickness ratio of the single lobe is smaller,i.***.sediments tend to accumulate vertically.The results demonstrate that the shape of slopes more comprehensively influences the 3-D architecture of lobes in natural deep-sea systems than previously other lobe deposits and analogue experiments,which helps us better understand the development and evolution of the distal parts of turbidite systems.

关键词： Submarine fan Seafloor topography Sedimentary architecture Slope system SW Indian ocean

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Microstructure and Mechanical Behavior of Mg-Based Bimetal Plates with High Formability Sleeve by Co-extrusion

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 499-512页

作者： Yue-Hui Dang sheng-Lin Liu Xiao-Lei Ai Xiao-Wei feng Bo feng Zhuo Tian Ying-Fei Lin Huan-Tao Chen Kai-Hong Zheng School of Materials Science and Engineering Chang’an UniversityShaanxi 710064China Guangdong Key Laboratory of Metal Toughening Technology and Application Institute of New MaterialsGuangdong Academy of SciencesGuangzhou 510650China

In this study,microstructure and mechanical behavior of two types of Mg-based bimetal plates with a high formability sleeve were systematically studied,with a great emphasis on the effect of the interface characteristic and the sleeve fraction on the plasticity of composite plates.The rule of mixtures(ROM)for elongation was also addressed.The results show that when there is no or thin diffusion layer with thickness of about 3μm,Mg-based bimetal plates have a good plasticity with elongation of about 19-24%,and the ROM predicted elongations are very close to the experimental ones.In contrast,with a diffusion layer about 95-155μm thick,Mg-based bimetal plates exhibit a poor plasticity with elongation of about 11-17%,and the experimental elongations largely deviate from the ROM predictions.The plasticity of Mg-based bimetal plates increases with increasing sleeve fraction.This study provides new insights on the plastic deformation of Mg-based bimetal composites with a high formability sleeve.

关键词： Mg-based composites Co-extrusion Microstructure Mechanical behavior Plastic deformation