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Numerical simulations of self-propelled swimming of 3D bionic fish school

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science china(Technological sciences) 2009年第3期52卷 658-669页

作者： wu chuijie1 & wang liang2 1 State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian univ.rsity of technology, Dalian 116024, china 2 Research Center for Fluid Dynamics, People’s Liberation Army univ.rsity of science and technology, nanjing 211101, china State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116024 China Research Center for Fluid Dynamics People’s Liberation Army University of Science and Technology Nanjing 211101 China

Numerical simulations of self-propelled swimming of a three dimensional bionic fish and fish school in a viscous fluid are carried out. This is done with the assistance of a parallel software package produced for 3D moving boundary problems. This computational fluid dynamics package combines the adaptive multi-grid finite volume method, the immersed boundary method and VOF (volume of fluid) method. By using the package results of the self-propelled swimming of a 3D bionic fish and fish school in a vis- cous fluid are obtained. With comparison to the existing experimental measurements of living fishes, the predicted structure of vortical wakes is in good agreement with the measurements.

关键词： adaptive multi-grid immersed boundary method self-propelled swimming fish school 3D bionic fish

Strip flatness prediction of cold rolling based on ensemble methods

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Journal of Iron and Steel Research International 2024年第1期31卷 237-251页

作者： wu-quan Yang Zhi-ting Zhao liang-yu Zhu Xun-yang Gao Li wang school of Mechanical and Power Engineering Shenyang University of Chemical TechnologyShenyang110142LiaoningChina

Aiming at the problem of insufficient prediction accuracy of strip flatness at the outlet of cold tandem rolling,the prediction performance of strip flatness based on different ensemble methods was studied and a high-precision prediction ensemble model of strip flatness at the outlet was ***,based on linear regression(LR),K nearest neighbors(KNN),support vector regression,regression trees(RT),and backpropagation neural network(BPN),bagging,boosting,and stacking ensemble methods were used for ensemble ***,three existing ensemble models,i.e.,random forest,extreme random tree(ET)and extreme gradient boosting,were used to conduct experiments and compare the *** research shows that bagging,boosting,and stacking three ensemble methods have the most significant improvement in the prediction accuracy of the regression trees model,which is increased by 5.28%,6.51%,and 5.32%,*** the same time,the stacking ensemble method improves both the simple model and the complex model,and the improvement effect on the simple base model is the greatest,which is 4.69%higher than that of the base model *** all of the ensemble models,the stacking ensemble model of level-1(ET,AdaBoost-RT,LR,BPN)paired with level-2(LR)was discovered to be the best model(EALB-LR)and can be further studied for industrial applications.

关键词： Tandem cold rolling Flatness prediction Machine learning Ensemble method

Enhanced visible-light photocatalytic hydrogen evolution using two-dimensional carbon nitride sheets with the removal of amine groups

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Chinese Chemical Letters 2024年第2期35卷 446-450页

作者： Yu Zhang Liting wu Shaopeng wang Dingyi Yang Huan liang Yizhang wu Jian Hao Youqing wang Jianke Liu Yong wang Department of Physics Shaanxi University of Science and TechnologyXi'an 710021China school of Advanced Materials and Nanotechnology Academy of Advanced Interdisciplinary ResearchXidian UniversityXi'an 710126China The State Key Discipline Laboratory of Wide Band Gap Semiconductor technology Xidian UniversityXi'an 710126China Collaborative Innovation Center of Advanced Microstructures National Laboratory of Solid State MicrostructuresNanjing UniversityNanjing 210093China State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021China

Two-dimensional(2D)carbon nitride sheets(CNs)with atomically thin structures are regarded as one of the most promising materials for solar energy ***,due to their substantially enlarged bandgap caused by the strong quantum size effect and their incomplete polymerisation with a large number of non-condensed surface amino groups,the practical applicability of CNs in photocatalysis is *** this study,CNs with broad visible-light absorption were synthesised using a 5-min fast thermal *** removal of uncondensed amine groups reduces the bandgap of CNs from 3.06 eV to 2.60 eV,increasing their absorption of visible ***,the CNs were distorted after annealing,which can differentiate the spatial positions of electrons and holes,enhancing the visible-light absorption *** a result,when exposed to visible light,the photocatalytic hydrogen production activity of atomically thin 2D CNs rose by 8.38 *** research presents a dependable and speedy method for creating highly effective visible-light photocatalysts with narrowed bandgaps and improved visible-light absorption.

关键词： 2D carbon nitride sheets Rapid thermal annealing DFT calculations Visible-light absorption visible-light photocatalysis

Insight into the mechanism of 5-hydroxymethylfurfural electroreduction to 2,5-bis(hydroxymethyl)furan over Cu anchored N-doped carbon nanosheets

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Nano Research 2024年第9期17卷 7991-7999页

作者： Haoran wu Xinwei Chen Haishan Xu Runlu Yang Xin wang Junying Chen Zhenbing Xie liang wu Yiyong Mai school of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China school of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Key Laboratory of Electrical Insulation and Thermal AgeingShanghai Jiao Tong UniversityShanghai 200240China Department of Chemistry Tangshan Normal UniversityTangshan 063000China

Design of non-noble metal electrocatalysts for biomass conversion to high-value chemicals and understanding the related catalytic mechanisms are of profound significance but have remained a major ***,we developed a novel biomass-derived electrocatalyst(denoted as Cu/NC),featuring with electron-deficient copper nanoparticles anchored on N-doped carbon nanosheets,for the electrochemical reduction of 5-hydroxymethylfurfural(HMF)to 2,5-bis(hydroxymethyl)furan(BHMF,a vital precursor of functional polymers).The optimized Cu/NC electrocatalyst exhibited an excellent performance with high Faradaic efficiency(89.5%)and selectivity(90.8%)of BHMF at a low concentration of HMF(18.1 mM).Even at a very high HMF concentration(108.6 mM),the Faraday efficiency and selectivity of BHMF could still reach 74.8%and 81.1%,*** performance approached those of the reported noble metal-based *** study revealed that the N doping in the Cu/NC catalyst could regulate the electronic structure of Cu,strengthening the adsorption of the HMF carbonyl group,and thus boosting the selectivity of ***,strong electronic metal-support interactions of Cu and the N-doped carbon support optimized the charge transfer rate,thus promoting the dissociation of water to the active hydrogen(H^(*))species and boosting the reaction kinetic rate of H^(*)and HMF.

关键词： biomass 5-hydroxymethylfurfural electrochemical reduction N-doped carbon materials 2,5-bis(hydroxymethyl)furan

universal architecture and defect engineering dual strategy for hierarchical antimony phosphate composite toward fast and durable sodium storage

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Journal of Energy Chemistry 2024年第3期90卷 110-119,I0004页

作者： Jiawei wu Gaoyu wang Wei Zhang Lixiang wang Jian Peng Qinghua Li Zhixin liang Wenbo Fan Jiazhao wang Shaoming Huang school of Materials and Energy Guangzhou Key Laboratory of Low-Dimensional Materials and Energy Storage DevicesGuangdong University of TechnologyGuangzhou 510006GuangdongChina school of Mechanical and Electrical Engineering Jiaxing Nanhu UniversityJiaxing 314001ZhejiangChina Institute for Superconducting and Electronic Materials Australian Institute for Innovative MaterialsUniversity of WollongongInnovation CampusSquires WayNorth WollongongNSW2522Australia

Antimony(Sb)-ba sed anode materials are feasible candidates for sodium-ion batteries(SIBs) due to their high theoretical specific capacity and excellent electrical ***,they still suffer from volume distortion,structural collapse,and ionic conduction interruption upon ***,a hierarchical array-like nanofiber structure was designed to address these limitations by combining architecture engineering and anion tuning strategy,in which SbPO_(4-x) with oxygen vacancy nanosheet arrays are anchored on the surface of interwoven carbon nanofibers(SbPO_(4-x)@CNFs).In particular,bulky PO_(4)^(3-) anions mitigate the large volume distortion and generate Na_(3)PO_(4) with high ionic conductivity,collectively improving cyclic stability and ionic transport *** abundant oxygen vacancies substantially boost the intrinsic electronic conductivity of SbPO_4,further accelerating the reaction *** addition,hierarchical fibrous structures provide abundant active sites,construct efficient conducting networks,and enhance the electron/ion transport *** from the advanced structural design,the SbPO_(4-x)@CNFs electrodes exhibit outstanding cycling stability(1000 cycles at 1.0 A g^(-1) with capacity decay of 0.05% per cycle) and rapid sodium storage performance(293.8 mA h g^(-1) at 5.0 A g^(-1)).Importantly,systematic in-/ex-situ techniques have revealed the "multi-step conversion-alloying" reaction process and the "battery-capacitor dual-mode" sodium-storage *** work provides valuable insights into the design of anode materials for advanced SIBs with elevated stability and superior rate performance.

关键词： SbPO_(4) anodes Hierarchical nanostructures Oxygen vacancy Stress dispersion Sodium-ion batteries

Effects of Hydrogen Charging Time and Pressure on the Hydrogen Embrittlement Susceptibility of X52 Pipeline Steel Material

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 293-307页

作者： Hong-Jiang Wan Xiao-Qi wu Hong-liang Ming Jian-Qiu wang En-Hou Han school of Materials science and Engineering University of Science and Technology of ChinaShenyang110016China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China school of Materials science and Engineering Northeastern UniversityShenyang110819China Institute of Corrosion science and technology Guangzhou510530China

The effects of hydrogen charging time and pressure on the hydrogen embrittlement(HE)susceptibility of X52 pipeline steel material are studied by slow strain rate tensile *** fracture morphologies of the specimens are observed by scanning electron *** HE susceptibility of the X52 pipeline steel material increases with an increase in both hydrogen charging time and hydrogen *** a charging time of 96 h,the HE susceptibility index reaches 45.86%,approximately 3.6 times that at a charging time of 0 ***,a charging pressure of 4 MPa results in a HE susceptibility index of 31.61%,approximately 2.5 times higher than that at a charging pressure of 0.3 MPa.

关键词： Hydrogen embrittlement X52 pipeline steel material Tubular specimen Hydrogen charging time Hydrogen charging pressure

A data-driven approach to RUL prediction of tools

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Advances in Manufacturing 2024年第1期12卷 6-18页

作者： Wei Li liang-Chi Zhang Chu-Han wu Yan wang Zhen-Xiang Cui Chao Niu Department of Mechanical Engineering University College LondonLondonWC1E 7JEUK Shenzhen Key Laboratory of Cross-Scale Manufacturing Mechanics Southern University of Science and TechnologyShenzhen518055GuangdongPeople’s Republic of China SUSTech Institute for Manufacturing Innovation Southern University of Science and TechnologyShenzhen518055GuangdongPeople’s Republic of China Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen518055GuangdongPeople’s Republic of China school of Mechanical and Manufacturing Engineering The University of New South WalesKensingtonNSW2052Australia Baoshan Iron&Steel Co. Ltd.Shanghai200941People’s Republic of China

An effective and reliable prediction of the remaining useful life(RUL)of a tool is important to a metal forming process because it can significantly reduce unexpected maintenance,avoid machine shutdowns and increase system *** study proposes a new data-driven approach to the RUL prediction for metal forming processes under multiple contact sliding *** data-driven approach took advantage of bidirectional long short-term memory(BLSTM)and convolutional neural networks(CNN).A pre-trained lightweight CNN-based network,WearNet,was re-trained to classify the wear states of workpiece surfaces with a high accuracy,then the classification results were passed into a BLSTM-based regression model as inputs for RUL *** experimental results demonstrated that this approach was able to predict the RUL values with a small error(below 5%)and a low root mean square error(RMSE)(around 1.5),which was more superior and robust than the other state-of-the-art methods.

关键词： Remaining useful life(RUL) Bidirectional long short-term memory(BLSTM) Data-driven approach Metal forming

Several whitefly genome assemblies and an integrated whitefly gene search platform

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Insect science 2024年第1期31卷 299-306页

作者： Xingnuo Li Peng liang Mingyue wu Shaoli wang Qingjun wu Wen Xie Youjun Zhang State Key Laboratory of Vegetable Biobreeding Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijingChina Sanya Academy of Troprical Agricultural Sciense SanyaHainanChina National Research Institute of Breeding in Hainan Chinese Academy of Agricultural SciencesSanyaHainanChina

Dear Editor,The characteristics and importance of the whitefly Bemisia tabaci as an economic pest seem to continually get more and more *** the whiteflies *** including,at least 11 genetic groups and 36 morphologically indistinguishable cryptic species,invasive MEAMl(Middle East-Asia Minor 1,"B"type)and MED(the Mediterranean,"Q"type)are the 2 most destructive cryptic species of the B.

关键词： Middle white East

Masses of the conjectured H-dibaryon at different temperatures

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Chinese Physics C 2024年第8期48卷 83-93页

作者： liang-Kai wu Han Tang Ning Li Xin-Yang wang school of Physics and Electronic Engineering Jiangsu UniversityZhenjiang 212013China Center for Fundamental Physics School of Mechanics and PhysicsAnhui University of Science and TechnologyHuainan 232001China

We present a lattice QCD determination of masses of the conjectured H-dibaryon,denoted as mH,at nine different temperatures:T/T_(c)=0.24,0.63,0.76,0.84,0.95,1.09,1.27,1.52,and *** masses of baryons N,Σ,Ξ,andΛat different temperatures were also *** simulations were performed on an anisotropic lattice with N_(f)=2+1 flavours of clover fermion at a quark mass corresponding to mπ=384(4)*** thermal ensembles were provided by the FASTSUM collaboration,whereas the zero temperature ensembles were provided by the Hadspec *** also calculated the spectral density of the correlation function of those *** spectral density distributions show a rich peak structure at the lowest temperature;at intermediate temperatures,the mass values of those particles obtained by the extrapolation method reflect a two-peak *** the spectral density for the octet baryon becomes smooth at T/T_(c)=1.27,1.52,and 1.90,the spectral density for the H-dibaryon becomes smooth at T/T_(c)=*** T/T_(c)=0.24,the mass difference of the H-dibaryon andΛpair,expressed asΔm=m_(H)−2m_(Λ),was estimated to beΔm=−14.6(6.2)MeV,which suggests the existence of a bound H-dibaryon state.

关键词： lattice QCD H-dibaryon spectral function clover fermion finite temperature