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Finite element analysis and experimental validation of polymer-metal contacts in block-on-ring configuration

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Friction 2024年第3期12卷 554-568页

作者： K.Y.Eayal AWWAD Khosro FALLAHNEZHAD B.F.YOUSIF Ahmad MOSTAFA Omar ALAJARMEH A.SHALWAN Xuesen ZENG Mechanical Engineering Department Faculty of EngineeringTafila Technical UniversityTafila 66110Jordan Medical Device Research Institute College of Science and EngineeringFlinders UniversitySouth Australia 5042Australia Centre for future Materials University of Southern QueenslandToowoomba 4350Australia Department of Manufacturing Engineering Technology Public Authority for Applied Education and TrainingKuwait 13092Kuwait

The wear profile analysis,obtained by different tribometers,is essential to characterise the wear ***,most of the available methods did not take the stress distribution over the wear profile in consideration,which causes inaccurate *** this study,the wear profile of polymer–metal contact,obtained by block-on-ring configuration under dry sliding conditions,was analysed using finite element modelling(FEM)and experimental ***’s wear equation was integrated into a developed FORTRAN-UMESHMOTION code linked with Abaqus software.A varying wear coefficient(k)values covering both running-in and steady state regions,and a range of applied loads involving both mild and severe wear regions were measured and implemented in the *** FEM was in good agreement with the *** model reproduced the stress distribution profiles under variable testing conditions,while their values were affected by the sliding direction and maximum wear depth(hmax).The largest area of the wear profile,exposed to the average contact stresses,is defined as the normal *** the critical zones were characterized by high stress concentrations reaching up to 10 times of that at the normal *** wear profile was mapped to identify the critical zone where the stress concentration is the key point in this *** surface features were examined in different regions using scanning electron microscope(SEM).Ultimately,SEM analysis showed severer damage features in the critical zone than that in the normal zone as proven by ***,the literature data presented and considered the wear features the same at any point of the wear *** this study,the normal zone was determined at a stress value of about 0.5 MPa,whereas the critical zone was at about 5.5 *** wear behaviour of these two zones showed totally different features from one another.

关键词： polymer-to-metal contact block-on-ring wear profile wear model

Establishment of a three-dimensional particle library for graded crushed stone based on a new aggregate morphology characterization method

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 117-130页

作者： Haitao Ge Aimin Sha Zhenqiang Han School of future Transportation Chang'an UniversityXi'an 710064China University of Strasbourg INSA StrasbourgCNRSICubeUMR 7357Strasbourg F-67000France School of Highway Chang'an UniversityXi'an 710064China Key Laboratory for Special Area Highway Engineering of Ministry of education Chang'an UniversityXi'an 710064China

The morphology of graded crushed stone(GCS)particles has an essential influence on the performance of aggregate *** impact of particle shape is a comprehensive effect that cannot be considered separately,leading to difficulties in establishing the relationship between the mixture properties and the aggregate morphology by using laboratory *** discrete element method(DEM)is an effective way widely adopted to reconstruct the morphology of particles and simulate performance tests of granular ***,selecting limited particles characterizing a real particle-assembly for simulation is still a challenge in current research due to the inherent rich variability of particle *** this study,based on the acquisition of three-dimensional(3D)aggregate shapes by using laser scanning,ellipsoid index(EDI)translating the particle shape as a function of surface area,volume,and contour length is proposed to comprehensively evaluate aggregate ***,a particle library capable of characterizing aggregate morphology distribution is established based on the statistics of the corresponding morphological characteristics of particle *** model reliability is validated by carrying out a series of experimental and numerical penetration tests with nine different *** established particle library can be used to model aggregate mixtures and the proposed simulation framework is promising for optimizing the mixture gradation design numerically.

关键词： Particle library Discrete element method 3D laser scanning Coarse aggregate Morphology characterization Gradation design

Traditional Meiyu-Baiu has been suspended by global warming

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National Science Review 2024年第7期11卷 126-134页

作者： Zhicong Yin Xiaolei Song Botao Zhou Wenhao Jiang Huopo Chen Huijun Wang Key Laboratory of Meteorological Disaster Ministry of Education/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&Technology Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of Sciences

More than 1000 years, the Meiyu–Baiu have shaped the uniqueness of natural resources, civilization and culture in the Yangtze River Basin of China and the main islands of Japan. In recent decades, frequent rainstorms and droughts have seemingly diminished the misty features of traditional Meiyu–Baiu ***, there is still no consensus on whether their traditional nature is suspended. In this study, we quantitatively demonstrate that the Meiyu–Baiu almost completely lost their traditional features during 1961–2023, ～80% of which can be attributed to anthropogenic warming. Furthermore, in a warmer future,the traditional Meiyu–Baiu will be more unlikely to appear. This study underscores the urgency in adapting to climate shift because destructive extremes are measurably taking the place of mild and maternal rains.

关键词： global warming Meiyu–Baiu extremes human activity culture and civilization

Cu-catalyzed regioselective diborylation of 1,3-enynes for the efficient synthesis of 1,4-diborylated allenes

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Chinese Chemical Letters 2024年第5期35卷 141-144页

作者： Wujun Jian Mong-Feng Chiou Yajun Li Hongli Bao Song Yang National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationCenter for R&D of Fine Chemicals of Guizhou UniversityGuiyang 550025China Strait Institute of Flexible Electronics(SIFE Future Technologies)Fujian Normal UniversityFuzhou 350117China Key Laboratory of Coal to Ethylene Glycol and Its Related Technology State Key Laboratory of Structural ChemistryFujian Institute of Research on the Structure of MatterUniversity of Chinese Academy of SciencesFuzhou 350002China

Borylation of 1,3-enynes with bis(boronate)compounds often ends up with the formation of hydroborylated products,leaving the diborylation of 1,3-enynes for the formation of 1,4-diborylated allenes to be ***,a copper-catalyzed chemo-,regio-,and stereo-selective diborylation of 1,3-enynes for the efficient construction of 1,4-diborylated allenes under base-free conditions was reported.A wide range of 1,3-enynes bearing various functional groups can participant in the reaction and afforded the corresponding 1,4-diborylated allenes in good to excellent yields,which was enabled by the protocol of Bpin to BF3K *** borylcopper species was supposed to selectively attack the C-C triple bond of the 1,3-enynes.

关键词： Copper catalysis Regioselective 1,3-Enynes Borylation Allenes

Modulating charge separation and transfer for high-performance photoelectrodes via built-in electric field

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1126-1146页

作者： Houyan Cheng Peng Liu Yuntao Cui Ru Ya Yuxiang Hu Jinshu Wang Key Laboratory of Advanced Functional Materials of education Ministry of China Faculty of Engineering and ManufacturingBeijing University of TechnologyBeijing 100124China Key Laboratory of Cryogenic Science and Technology and Beijing Key Lab of Cryo-Biomedical Engineering Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China Inner Mongolia academy of Science and Technology Hohhot 010020China

Constructing a built-in electric field has emerged as a key strategy for enhancing charge separation and transfer,thereby improving photoelectrochemical ***,considerable efforts have been devoted to this *** review systematically summarizes the impact of built-in electric fields on enhancing charge separation and transfer mechanisms,focusing on the modulation of built-in electric fields in terms of depth and ***,mechanisms and tuning strategies for built-in electric fields are ***,the state-of-the-art works regarding built-in electric fields for modulating charge separation and transfer are summarized and categorized according to surface and interface ***,current strategies for constructing bulk built-in electric fields in photoelectrodes are explored,and insights into future developments for enhancing charge separation and transfer in high-performance photoelectrochemical applications are provided.

关键词： photoelectrochemical water splitting bulk built-in electric field cation intercalation charge separation and transfer

Analytical model of vertical load acting on jacked pipe considering soil arching effect in cohesionless soil

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Underground Space 2024年第1期14卷 263-284页

作者： Yu Zhang Lianjin Tao Xu Zhao Jun Liu Weizhang Liao Fei Guo Xiaohui Yang Ruiqin Zhong Beijing Advanced Innovation Center for future Urban Design Beijing University of Civil Engineering and ArchitectureBeijing 102627China The Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing 100024China Beijing Municipal Construction Group Co. LtdBeijing 100045China Beijing Municipal Engineering Institute Beijing 100037China

For the project of pipe jacking in cohesionless soil,it is key to determine the vertical load on jacked pipe so as to predict the jacking force *** this paper,a new parabolic soil arching model was proposed to calculate the vertical load on jacked *** proposed analytical model was composed of parabolic soil arching zone,parabola-typed collapse zone and friction arch *** with existing literature,the key parameters(i.e.,height of parabolic soil arching,horizontal pressure coefficient and width and height of friction arch)were *** addition,considering that the trajectory of major stress is parabola,the formula of horizontal pressure coefficient was deduced in the friction *** parabolic soil arching zone is assumed as a three-hinged arch with reasonable arch axis,and the formula of load transfer was derived considering the transition effect of parabolic soil *** results of experiment,theoretical models and numerical model were adopted to verify the proposed analytical ***,the influence of the key parameters on the vertical load on jacked pipe were also discussed in *** work provides a meaningful reference for evaluating the vertical load on jacked pipe for design of pipe jacking.

关键词： Jacked pipe Soil arching effect Theoretical model Parabolic soil arching model Vertical load

Fast source mask co-optimization method for high-NA EUV lithography

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Opto-Electronic Advances 2024年第4期7卷 44-54页

作者： Ziqi Li Lisong Dong Xu Ma Yayi Wei EDA Center Institute of Microelectronics of Chinese Academy of SciencesBeijing 100029China Key Laboratory of Photoelectronic Imaging Technology and System of Ministry of education of China School of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China University of Chinese academy of Sciences Beijing 100049China Guangdong Greater Bay Area Applied Research Institute of Integrated Circuit and Systems Guangzhou 510700China

Extreme ultraviolet(EUV)lithography with high numerical aperture(NA)is a future technology to manufacture the integrated circuit in sub-nanometer ***,source mask co-optimization(SMO)is an extensively used approach for advanced lithography process beyond 28 nm technology *** work proposes a novel SMO method to improve the image fidelity of high-NA EUV lithography system.A fast high-NA EUV lithography imaging model is established first,which includes the effects of mask three-dimensional structure and anamorphic ***,this paper develops an efficient SMO method that combines the gradient-based mask optimization algorithm and the compressivesensing-based source optimization algorithm.A mask rule check(MRC)process is further proposed to simplify the optimized mask *** illustrate that the proposed SMO method can significantly reduce the lithography patterning error,and maintain high computational efficiency.

关键词： computational lithography high-NA EUV lithography source-mask co-optimization lithography imaging model

Deformable Catalytic Material Derived from Mechanical Flexibility for Hydrogen Evolution Reaction

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Nano-Micro Letters 2024年第2期16卷 287-311页

作者： Fengshun Wang Lingbin Xie Ning Sun Ting Zhi Mengyang Zhang Yang Liu Zhongzhong Luo Lanhua Yi Qiang Zhao Longlu Wang College of Electronic and Optical Engineering&College of Flexible Electronics(future Technology) Nanjing University of Posts&Telecommunications(NJUPT)9 WenyuanNanjing 210023People’s Republic of China Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of education School of ChemistryXiangtan UniversityXiangtan 411105People’s Republic of China State Key Laboratory of Organic Electronics and Information Displays&Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials(IAM)&Institute of Flexible Electronics(Future Technology)Nanjing University of Posts&Telecommunications9 WenyuanNanjing 210023People’s Republic of China

Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent years,deformable catalysts for HER have made great progress and would become a research *** catalytic activities of deformable catalysts could be adjustable by the strain engineering and surface *** surface curvature of flexible catalytic materials is closely related to the electrocatalytic HER ***,firstly,we systematically summarized self-adaptive catalytic performance of deformable catalysts and various micro–nanostructures evolution in catalytic HER ***,a series of strategies to design highly active catalysts based on the mechanical flexibility of lowdimensional nanomaterials were *** but not least,we presented the challenges and prospects of the study of flexible and deformable micro–nanostructures of electrocatalysts,which would further deepen the understanding of catalytic mechanisms of deformable HER catalyst.

关键词： Deformable catalytic material Micro-nanostructures evolution Mechanical flexibility Hydrogen evolution reaction

面向碱性析氢反应的原子级优化Fe-Pt金属间化合物催化剂表面终结态探索

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Science Bulletin 2024年第8期69卷 1091-1099页

作者：梁庆孟繁玲李文文邹旭宋可心葛昕姜周刘玉华刘美琦李振宇董韬文陈中军张伟郑伟涛 Key Laboratory of Automobile Materials(Ministry of education) School of Materials Science and EngineeringElectron Microscopy CenterInternational Center of Future ScienceJilin Provincial International Cooperation Key Laboratory of High-Efficiency Clean Energy MaterialsJilin UniversityChangchun 130012China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Controlling the atomic arrangement of elemental atoms in intermetallic catalysts to govern their surface and subsurface properties is a crucial but challenging endeavor in electrocatalytic *** hydrogen evolution reaction(HER),adjusting the d-band center of the conventional noble-metallic Pt by introducing Fe enables the optimization of catalytic ***,a notable gap exists in research on the effective transition from disordered Fe/Pt alloys to highly ordered intermetallic compounds(IMCs)such as FePt_(3)in the alkaline HER,hampering their broader *** this study,a series of catalysts FePt_(3-x)H(x=5,6,7,8 and 9)supported on carbon nanotubes(CNTs)were synthesized via a simple impregnation method,along with a range of heat treatment processes,including annealing in a reductive atmosphere,to regulate the order degree of the arrangement of Fe/Pt atoms within the FePt_(3)*** using advanced microscopy and spectroscopy techniques,we systematically explored the impact of the order degree of FePt_(3)in the *** as-prepared FePt_(3)-8H exhibited notable HER catalytic activity with low overpotentials(η=37 mV in 1.0 mol L^(-1)KOH)at j=10 mA cm^(-2).The surface of the L1_(2)FePt_(3)-8H catalyst was demonstrated to be *** Pt on the surface was not easily oxidized due to the unique Fe/Pt coordination,resulting in significant enhancement of HER performance.

关键词： Intermetallic Hydrogen evolution reaction Surface Catalyst