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Electromagnetic characteristic analysis and design of a linear motor used for ultra-high-speed EMS maglev train

Science China(Technological Sciences) 2024年第6期67卷 1957-1973页

作者： GAO Han SHI TingNa GAO XinMai LEI YanXiao YAN Dong GUO LiYan YAN Yan College of Electrical Engineering Zhejiang UniversityHangzhou310027China Zhejiang University Advanced Electrical Equipment Innovation Center Hangzhou311107China state key laboratory of high-speed maglev transportation technology Qingdao266100China CRRC Qingdao Sifang Co.Ltd. Qingdao266111China

The operating speed of the commercial electromagnetic suspension(EMS)maglev train has been over 430 km/h,making it the fastest means of land *** the increasing demands of people traveling,it is necessary to further improve the operating speed of maglev *** to examine whether the existing EMS system can meet the requirements of ultra-highspeed operation(more than 600 km/h),the electromagnetic characteristics of an EMS linear motor under the operating speed of 600–1000 km/h fed by a square-wave voltage supply is investigated in this ***,an electromagnetic field model of the EMS system under the square-wave voltage supply is established to investigate its electromagnetic performance,e.g.,the characteristics of phase current,the magnetic flux density,and the electromagnetic ***,the relationship between the harmonic components of the air-gap magnetic flux density and electromagnetic force is investigated using the two-dimensional fast Fourier transform(2D-FFT)to reveal the mechanism of electromagnetic force ***,to address the issues of excessive armature current density and significant electromagnetic force ripple,the linear motor is re-designed by enlarging the stator slot area and reshaping the mover's main magnetic ***,the Taguchi method is used to further improve the electromagnetic characteristics of the linear electric ***,the effectiveness of the proposed optimal design is validated by the finite-element analysis(FEA)based co-simulation.

关键词： ultra-high-speed maglev transportation electromagnetic suspension(EMS) linear motor electromagnetic force ripple suppression

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Enhanced high-temperature mechanical properties of laser-arc hybrid additive manufacturing of Al-Zn-Mg-Cu alloy via microstructure control

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Journal of Materials Science & technology 2024年第2期169卷 220-234页

作者： Dehua Liu Dongjiang Wu Yunsong Wang Zhuo Chen Changrong Ge Qingyu Zhao Fangyong Niu Guangyi Ma state key laboratory of high-performance Precision Manufacturing Dalian University of TechnologyDalian 116024China

Recently,rapid and cost-effective additive manufacturing solutions for lightweight aluminum alloys with excellent high-temperature mechanical properties have been increasingly in *** this study,we combined laser-arc hybrid additive manufacturing with solution and artificial aging treatments to achieve Al-Zn-Mg-Cu alloy with favorable high-temperature strength via microstructure *** pores became the major defect in the as-deposited and heat-treated *** continuous distribution of eutectics with hard-brittle characteristics at the grain boundaries was destructed following heat ***-densityηprecipitates were uniformly dispersed in the heat-treated Al-Zn-Mg-Cu alloy,whereas appeared coarsened and dissolved at 473 K,owing to the rapid diffusion of Zn and *** average 0.2%yield strength(318±16 MPa)and ultimate tensile strength(362±20 MPa)at 473 K af-ter heat treatment were enhanced by approximately 58%and 51%,respectively,compared to those of the as-deposited *** addition,theηprecipitates contributed to lattice distortions and strain fields,which prevented dislocation motion and increased slip deformation resistance at high *** as-deposited specimen exhibited intergranular fracture at 473 K,with cracks preferring to propagate along the aggregated ***,crack propagation proceeded in the sections with more pores in the heat-treated *** approach may provide a valid option for achieving alu-minum alloys with excellent high-temperature mechanical properties.

关键词： Laser-arc hybrid additive manufacturing Al-Zn-Mg-Cu alloy high-temperature strength Heat treatment,Microstructure evolution

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Precise measurement of geometric and physical quantities in cutting tools inspection and condition monitoring: A review

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Chinese Journal of Aeronautics 2024年第4期37卷 23-53页

作者： Wenqi WANG Wei LIU Yang ZHANG Yang LIU Peidong ZHANG Zhenyuan JIA state key laboratory of high-Performance Precision Manufacturing Dalian University of TechnologyDalian 116024China

As one of the most important terminals in machining, cutting tools have been widely used for components manufacturing in aerospace and other industries. The quality of these components and processing efficiency are closely linked to the performance of cutting tools. Therefore, it is essential and critical to inspect the cutting tools and monitor the condition during the stage of manufacturing and machining. This review aims to discuss and summarize the key problems, methods,and techniques from the perspective of the tool geometric and the physical quantities measurement,including machine vision, physical sensors and data processing. It is worth mentioning that we focus on the topic of precision measurement methods and discuss universal solutions by identifying the common characteristics of the measured quantities. Eventually, the challenges and future trends for the development of in-depth research and practical applications are concluded. The research and application of precise measurement techniques for geometric and physical quantities will better promote the development of intelligent manufacturing.

关键词： Cutting tools Mechanical measurement Machine vision Physical sensors Tool condition monitoring

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Atomistic understanding of rough surface on the interfacial friction behavior during the chemical mechanical polishing process of diamond

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Friction 2024年第6期12卷 1119-1132页

作者： Song YUAN Xiaoguang GUO Hao WANG Renke KANG Shang GAO state key laboratory of high-performance Precision Manufacturing Dalian University of TechnologyDalian 116024China

The roughness of the contact surface exerts a vital role in *** is still a significant challenge to understand the microscopic contact of the rough surface at the atomic ***,the rough surface with a special root mean square(RMS)value is constructed by multivariate Weierstrass–Mandelbrot(W–M)function and the rubbing process during that the chemical mechanical polishing(CMP)process of diamond is mimicked utilizing the reactive force field molecular dynamics(ReaxFF MD)*** is found that the contact area A/A0 is positively related with the load,and the friction force F depends on the number of interfacial bridge *** the surface roughness will increase the friction force and friction *** model with low roughness and high lubrication has less friction force,and the presence of polishing liquid molecules can decrease the friction force and friction *** RMS value and the degree of damage show a functional relationship with the applied load and lubrication,i.e.,the RMS value decreases more under larger load and higher lubrication,and the diamond substrate occurs severer damage under larger load and lower *** work will generate fresh insight into the understanding of the microscopic contact of the rough surface at the atomic level.

关键词： diamond random roughness reactive force field molecular dynamics(ReaxFF MD) friction Weierstrass-Mandelbrot(W-M)function chemical mechanical polishing(CMP)

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Rapid and controllable in-situ self-assembly of main-group metal nanofilms for highly efficient CO_(2)electroreduction to liquid fuel in flow cells

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Nano Research 2024年第6期17卷 5718-5725页

作者： Miao Wang Huaizhu Wang Yaoda Wang Junchuan Liang Mengfei Zhu Jiarui Li Zuoxiu Tie Zhong Jin state key laboratory of Coordination Chemistry MOE Key Laboratory of Mesoscopic ChemistryMOE Key Laboratory of High Performance Polymer Materials and TechnologyJiangsu Key Laboratory of Advanced Organic MaterialsTianchang New Materials and Energy Technology Researc

The electrocatalytic reduction of CO_(2)is a promising pathway to generate renewable fuels and ***,its advancement is impeded by the absence of electrocatalysts with both high selectivity and ***,we present a scalable in-situ thermal evaporation technique for synthesizing series of Bi,In,and Sn nanofilms on carbon felt(CF)substrates with a high-aspect-ratio *** resulting main-group metal nanofilms exhibit a homogeneously distributed and highly exposed catalyst surface with ample active sites,thereby promoting mass transport and ad-/desorption of reaction *** from the unique fractal morphology,the Bi nanofilms deposited on CF exhibit optimal catalytic activities for CO_(2)electroreduction among the designed metal nanofilms electrodes,with the highest Faradaic efficiency of 96.9%for formate production at−1.3 V *** hydrogen electrode(RHE)in *** an industrially relevant current density of 221.4 mA·cm−2 in flow cells,the Bi nanofilms retain a high Faradaic efficiency of 81.7%at−1.1 V(***)and a good long-term stability for formate ***,a techno-economic analysis(TEA)model shows the potential commercial viability of electrocatalytic CO_(2)conversion into formate using the Bi nanofilms *** results offer a green and convenient approach for in-situ fabrication of stable and inexpensive thin-film catalysts with a fractal structure applicable to various industrial settings.

关键词： CO_(2)electroreduction non-noble metal nanofilms flow cells efficiency and selectivity techno-economic analysis

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Conversion of a single-layer ANN to photonic SNN for pattern recognition

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Science China(Information Sciences) 2024年第1期67卷 261-270页

作者： Yanan HAN Shuiying XIANG Tianrui ZHANG Yahui ZHANG Xingxing GUO Yuechun SHI state key laboratory of Integrated Service Networks State Key Discipline Laboratory of Wide Bandgap Semiconductor TechnologyXidian University Yongjiang laboratory

This work presents a complete conversion scheme for photonic spiking neural networks(SNNs).We verified that the output of an artificial neural network(ANN) trained with the simulated optical activation function can be directly converted into the spike rate of a photonic spiking neuron *** reveal the feasibility of hardware implementation,we considered the effects of different bit precisions of data and weight,noise level,and bias current mismatch on the converted *** proposed scheme was evaluated using the Deterding vowel,IRIS,TIDIGITS,and MNIST datasets for pattern recognition,and achieved mean accuracies of 95.80%,98.67%,96.19%,and 92.33%,*** proposed scheme can convert an ANN into a photonic SNN with almost no precision loss,and the performance was comparable to that of an ANN trained with the rectified linear unit *** proposed scheme can enable the high-performance implementation of photonic SNNs.

关键词： photonic SNN conversion optical computing pattern recognition artificial neural network

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Prediction of high-embankment settlement combining joint denoising technique and enhanced GWO-v-SVR method

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 317-332页

作者： Qi Zhang Qian Su Zongyu Zhang Zhixing Deng De Chen School of Civil Engineering Southwest Jiaotong UniversityChengduChina MOE key laboratory of high speed Railway Engineering Southwest Jiaotong UniversityChengduChina

Reliable long-term settlement prediction of a high embankment relates to mountain infrastructure *** study developed a novel hybrid model(NHM)that combines a joint denoising technique with an enhanced gray wolf optimizer(EGWO)-n-support vector regression(n-SVR)***-embankment field measurements were preprocessed using the joint denoising technique,which in-cludes complete ensemble empirical mode decomposition,singular value decomposition,and wavelet packet ***,high-embankment settlements were predicted using the EGWO-n-SVR *** this method,the standard gray wolf optimizer(GWO)was improved to obtain the EGWO to better tune the n-SVR model *** proposed NHM was then tested in two case ***,the influences of the data division ratio and kernel function on the EGWO-n-SVR forecasting performance and prediction efficiency were *** results indicate that the NHM suppresses noise and restores details in high-embankment field ***,the NHM out-performs other alternative prediction methods in prediction accuracy and *** demonstrates that the proposed NHM is effective in predicting high-embankment settlements with noisy field ***,the appropriate data division ratio and kernel function for EGWO-n-SVR are 7:3 and radial basis function,respectively.

关键词： high embankment Settlement prediction Joint denoising technique Enhanced gray wolf optimizer Support vector regression

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Review and prospects on the low-voltage Na_(2)Ti_(3)O_(7) anode materials for sodium-ion batteries

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Journal of Energy Chemistry 2024年第1期88卷 446-460,I0011页

作者： Jun Dong Yalong Jiang Ruxing Wang Qiulong Wei Qinyou An Xiaoxing Zhang Hubei key laboratory for high-efficiency Utilization of Solar Energy and Operation Control of Energy Storage System Hubei University of TechnologyWuhan 430068HubeiChina state key laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430200HubeiChina Xiamen key laboratory of high-Performance Metals and Materials College of MaterialsXiamen UniversityXiamen 361005FujianChina state key laboratory of Advanced technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070HubeiChina

Due to its low cost and natural abundance of sodium,Na-ion batteries(NIBs)are promising candidates for large-scale energy storage *** development of ultralow voltage anode materials is of great significance in improving the energy density of ***-voltage anode materials,however,are severely lacking in *** all the reported insertion oxides anodes,the Na_(2)Ti_(3)O_(7) has the lowest operating voltage(an average potential of 0.3 V ***^(+)/Na)and is less likely to deposit sodium,which has excellent potential for achieving NIBs with high energy densities and high *** significant progress has been made,achieving Na_(2)Ti_(3)O_(7) electrodes with excellent performance remains a severe *** paper systematically summarizes and discusses the physicochemical properties and synthesis methods of Na_(2)Ti_(3)O_(7).Then,the sodium storage mechanisms,key issues and challenges,and the optimization strategies for the electrochemical performance of Na_(2)Ti_(3)O_(7) are classified and further ***,remaining challenges and future research directions on the Na_(2)Ti_(3)O_(7) anode are *** review offers insights into the design of high-energy and high-safety NIBs.

关键词： Sodium-ion batteries Low-voltage anode materials Na_(2)Ti_(3)O_(7) Electrochemical performances Electrochemical mechanism

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Simplified quantitative analysis method and its application in the insitu synthesized copper-based azide chips

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Defence technology（防务技术） 2024年第2期32卷 309-316页

作者： Jie Ren Yunfeng Li Mingyu Li Xingyu Wu Jiabao Wang Qingxuan Zeng state key laboratory of Explosion and technology Beijing Institute of TechnologyBeijing 100081China

Copper-based azide(Cu(N_(3))2 or CuN_(3),CA)chips synthesized by in-situ azide reaction and utilized in miniaturized explosive systems has become a hot research topic in recent ***,the advantages of in-situ synthesis method,including small size and low dosage,bring about difficulties in quantitative analysis and differences in ignition capabilities of CA *** aim of present work is to develop a simplified quantitative analysis method for accurate and safe analysis of components in CA chips to evaluate and investigate the corresponding ignition *** this work,Cu(N_(3))2 and CuN_(3)components in CA chips were separated through dissolution and distillation by utilizing the difference in solubility and corresponding content was obtained by measuring N_(3)-concentration through *** spectrophotometry method was optimized by studying influencing factors and the recovery rate of different separation methods was studied,ensuring the accuracy and reproducibility of test *** optimized method is linear in range from 1.0-25.0 mg/L,with a correlation coefficient R^(2)=0.9998,which meets the requirements of CA chips with a milligram-level content *** with the existing ICP method,component analysis results of CA chips obtained by spectrophotometry are closer to real component content in samples and have satisfactory ***,as its application in miniaturized explosive systems,the ignition ability of CA chips with different component contents for direct ink writing CL-20 and the corresponding mechanism was *** study provided a basis and idea for the design and performance evaluation of CA chips in miniaturized explosive systems.

关键词： Copper-based azide chips Spectrophotometry Separation method Quantitative analysis Ignition ability

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Long-wave infrared emission properties of strain-balanced InAs/InxGa1-xAsySb1-y type-Ⅱ superlattice on different substrates

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Rare Metals 2024年第7期43卷 3194-3204页

作者： Chao Shi Xuan Fang Hong-Bin Zhao Deng-Kui Wang Xi Chen Dan Fang Dong-Bo Wang Xiao-Hua Wang Jin-Hua Li state key laboratory of high Power Semiconductor Lasers School of PhysicsChangchun University of Science and Technology state key laboratory of Advanced Materials for Smart Sensing China General Research Institute for Nonferrous Metals Department of Opto-Electronic Information Science School of Materials Science and EngineeringHarbin Institute of Technology

high-performance type-Ⅱ superlattices of Ⅲ-Ⅴsemiconductor materials play an important role in the development and application of infrared optoelectronic *** the quality of epitaxial materials and clarifying the luminescent mechanism are of great significance for practic al applic *** this work,strain-balanced and high-quality In As/InxGa1-xAsySb1-ysuperlattices without lattice mismatch were achieved on InAs and GaSb substrates *** grown on In As substrate could exhibit higher crystal quality and surface flatness based on high-resolution X-ray diffraction（HRXRD） and atomic force microscopy（AFM） measurements' ***,the strain distribution phenomenon from geometric phase analysis indicates that fluctuations of alloy compositions in superlattices on GaSb substrate are more *** addition,the optical properties of superlattices grown on different substrates are discussed *** of the difference in fluctuations of element composition and interface roughness of superlattices on different substrates,the superlattices grown on In As substrate would have higher integral intensity and narrower full-width at half maximum of long-wave infrared ***,the thermal quenching of emission intensity indicates that the superlattices grown on the In As substrate have better recombination ability,which is beneficial for increasing the operating temperature of infrared optoelectronic devices based on this type of superlattices.

关键词： Photoluminescence Alloy compositions fluctuations InAs(Sb)/In x Ga 1− x As y Sb 1− y Type-II superlattice Substrate

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