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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 169-180页

作者： Huan Yang Ying Liu Jianbo Jin Kunmao Li Junjie Yang Lingjian Meng Chunbo Li wencai zhang Shengfeng Zhou Sino-German College of Intelligent Manufacturing Shenzhen Technology UniversityShenzhen518118China Institute of Advanced Wear and Corrosion Resistance and Functional Materials Jinan UniversityGuangzhou510632China Department of Orthopedics First Affiliated Hospital of Jinan UniversityGuangzhou510632China

Cu-bearing stainless steels(SSs)with high strength,excellent plasticity,and effective antimicrobial properties hold significant potential for applications in the marine *** this study,Cu-bearing SSs with copper ranging from 0 to 6.0 wt%were successfully prepared using selective laser melting(SLM)*** the Cu-bearing SSs with different copper contents,the effect of heat treatment on the microstructural and mechanical behaviors was studied *** observations revealed that the subgrain size of Cu-bearing SSs increased with heat treatment at 500℃ and 700℃ for 6 ***,the tensile strength and elongation increased after the heat treatment temperature due to the combined effect of dislocations,twins,andε-Cu precipitated ***,after heat treatment at 700℃,the SLM4.5Cu sample exhibited an abnormal rise in tensile strength and *** finding suggests that the diffusion strengthening caused byε-Cu precipitates exceeded the stacking fault ***,the tensile strength and elongation reached 693.32 MPa and 56.94%,*** work provides an efficient approach for preparing Cu-bearing SSs with exceptional strength and plasticity.

关键词： Selective laser melting Cu-bearing stainless steel(SS) Heat treatment Mechanical properties

Design and verification of an improved experimental platform for stray current in urban rail transit

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Journal of Measurement Science and Instrumentation 2024年第3期15卷 379-386页

作者： LI Yaning KANG Hong WANG Ye LI Wenfei JIAO Meng zhang wencai School of Automation and Electrical Engineering Lanzhou Jiaotong UniversityLanzhou 730070China School of Environmental and Municipal Engineering Lanzhou Jiaotong UniversityLanzhou 730070China

With the rapid development of urban rail transit,there have been an urgent problem of excessive stray *** the stray current distribution is random and difficult to verify in the field,we designed an improved stray current experimental platform by replacing the simulated aqueous solution with a real soil environment and by calculating the transition resistance by measuring the soil resistivity,which makes up for the defects in the previous ***,the mathematical models of rail-drainage net and rail-drainage netground were established,and the analytical expressions of current and voltage of rail,drainage net and other structures were *** addition,the simulation model was built,and the mathematical analysis results were compared with the simulation ***,the accuracy of the improved stray current experimental platform was verified by comparing the measured and simulation ***,based on the experimental results,the influence factors of stray current were *** relevant conclusions provide experimental data and theoretical reference for the study of stray current in urban rail transit.

关键词： urban rail transit stray current experimental platform transition resistance soil resistivity

碳纤维/酚醛复合材料射线检测高密度影像分析

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无损检测 2024年第9期46卷 7-11页

作者：张文才中国空空导弹研究院洛阳471000

碳纤维/酚醛复合材料是固体火箭发动机喷管耐高温部件的重要材料,从影像形貌、黑度分布规律方面入手,对某产品射线检测中发现的异常高密度影像,进行了总结、分类,并结合产品制备工艺和射线检测方法特点,对部分实物进行了解剖观察和理化... 详细信息

碳纤维/酚醛复合材料是固体火箭发动机喷管耐高温部件的重要材料,从影像形貌、黑度分布规律方面入手,对某产品射线检测中发现的异常高密度影像,进行了总结、分类,并结合产品制备工艺和射线检测方法特点,对部分实物进行了解剖观察和理化分析,确定了异常影像的产生原因为碳纤维团聚、高硅氧纤维掺杂、石块混入等,归纳了影像评判的方法和要素,以为同类产品的缺陷影像识别提供参考。

关键词：碳纤维复合材料射线检测高密度影像缺陷识别

Design and Research of Form Controlled Planar Folding Mechanism based on 4D Printing Technology

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Chinese Journal of Mechanical Engineering 2023年第4期36卷 281-293页

作者： wencai zhang Zhenghao Ge Duanling Li College of Mechanical and Electrical Engineering Shaanxi University of Science and TechnologyShaanxi 710021China School of Automation Beijing University of Posts and TelecommunicationsBeijing 100876China

The use of non-smart materials in structural components and kinematic pairs allows for flexible assembly in practical applications and is promising for aerospace ***,this approach can result in a complex structure and excessive kinematic pairs,which limits its potential applications due to the difficulty in controlling and actuating the *** smart materials have been integrated into certain mechanisms,such integration is generally considered a unique design for specific cases and lacks ***,organically combining universal mechanism design with smart materials and 4D printing technology,innovating mechanism types,and systematically exploring the interplay between structural design and morphing control remains an open research *** this work,a novel form-controlled planar folding mechanism is proposed,which seamlessly integrates the control and actuation system with the structural components and kinematic pairs based on the combination of universal mechanism design with smart materials and 4D printing technology,while achieving self-controlled dimensional ratio adjustment under a predetermined thermal *** design characteristics of the mechanism are analyzed,and the required structural design parameters for the preprogrammed design are derived using a kinematic *** smart materials and 4D printing technology,folding programs based on material properties and control programs based on manufacturing parameters are encoded into the form-controlled rod to achieve the preprogrammed design of the ***,two sets of prototype mechanisms are printed to validate the feasibility of the design,the effectiveness of the morphing control programs,and the accuracy of the theoretical *** mechanism not only promotes innovation in mechanism design methods but also shows exceptional promise in satellite calibration devices and spacecraft walking systems.

关键词： Form-controlled mechanism Self-folding Smart materials 4D printing Morphing control

Neural bases of reappraisal regulatory effect on negative emotion in high reappraisers

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Neural Regeneration Research 2012年第32期7卷 2542-2547页

作者： wencai zhang Jin Luo Key Laboratory of Mental Health Institute of Psychology Chinese Academy of Sciences Beijing 100101 China Beijing Key Laboratory of Learning and Cognition Department of Psychology Capital Normal University Beijing 100048 China

Previous studies have reported that individual differences in reappraisal use are associated with partJcular patterns of neural activity. We hypothesized that if ＇high reappraisers＇（individuals who use reappraisal well in a behavioral experiment） completed two training sessions, they would exhibit more reliable patterns of neural activity related to cognitive reappraisal. In the present study, 13 high reappraisers were selected from 27 healthy volunteers through an initial behavioral experiment （first training） followed by a functional MRI experiment （second training）. Emotional images selected from the International Affective Picture System were used for both the behavioral and functional MRI sessions of the experiment. The behavioral results revealed that reappraisal reduced subjective unpleasantness. The functional MRI results revealed that the cognitive reappraisal used by high reappraisers decreased the activation of emotion-responsive regions, including the amygdala, insula, and cingulate gyrus, and increased the activation of regulation-related regions, including the inferior prefrontal cortex, orbital prefrontal cortex, and dorsal medial prefrontal cortex. These findings suggest the involvement of inferior orbital and dorsal medial prefrontal cortex in constructing reappraisal strategies that modulate activity in emotion-processing systems.

关键词： cognitive reappraisal negative emotion amygdala functional MRI neural regeneration

Leaching recovery of rare earth elements from the calcination product of a coal coarse refuse using organic acids

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Journal of Rare Earths 2022年第2期40卷 318-327,I0005页

作者： Bin Ji Qi Li wencai zhang Department of Mining and Minerals Engineering Virginia Polytechnic Institute and State UniversityBlacksburg Virginia 24061USA

Due to the increasing criticality of rare earth elements(REEs),it has become essential to recover REEs from alternative *** this study,systematic REEs leaching tests were performed on the calcination product of a coal coarse refuse using hydrochloric acid and different types of organic acid as *** results show that the recovery of REEs,especially heavy REEs(HREEs)and scandium(Sc),is improved by using selected organic *** acid and DL-malic acid afford the best leaching performances;whereas,malonic acid,oxalic acid,and DL-tartaric acid are inferior to hydrochloric *** of zeta potential measurements and solution chemical equilibrium calculations show that malonic acid is more likely adsorbed on the surface of the calcined material compared with citric acid and DL-malic *** adsorption may reduce the effective concentration of malonic species in solution and/or increase the amount of REEs adsorbed on the surface,thereby impairing the leaching *** with light REEs(LREEs),a stronger adsorption of the HREEs on the surface is observed from electro-kinetic test *** finding explains why organic acids impose a more positive impact on the leaching recovery of HREEs,By complexing with the HREEs,organic acids can keep the metal ions in solution and improve the leaching *** adsorption of Sc^(3+)on the surface is the lowest compared with other ***,rather than complexing,the organic anionic species likely play a function of solubilizing Sc from the solid,which is similar to that of hydrogen ions.

关键词： Rare earth elements Coal refuse Acid leaching Organic acids

Effects of contaminant metal ions on precipitation recovery of rare earth elements using oxalic acid

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Journal of Rare Earths 2022年第3期40卷 482-490,I0005页

作者： wencai zhang Aaron Noble Bin Ji Qi Li Department of Mining and Minerals Engineering Virginia Polytechnic Institute and State UniversityBlacksburgVA24061USA

Solution equilibrium calculations were performed in this study to understand the impact of contaminant metal ions on the precipitation efficiency of selected rare earth elements(Ce^(3+),Nd^(3+),and Y^(3+))using oxalic acid as a *** metal ions,Al^(3+) and Fe^(3+),are found to considerably affect the precipitation efficiency of *** Al^(3+) and Fe^(3+)concentrations are increased by 1×10^(−4) mol/L,in order to achieve an acceptable cerium recovery of 93%from solutions containing 1×10^(−4) mol/L Ce^(3+),oxalate dosage needs to increase by 1.2×10^(−4) and 1.68×10^(−4) mol/L,*** great impacts on the required oxalate dosage are also observed for Nd^(3+) and Y^(3+),which indicates that oxalic acid consumption and cost will be largely increased when the trivalent metal ions exist in REE-concentrated *** of the divalent metal ions on the oxalate dosage are ***,solution equilibrium calculation results show that the precipitation of Fe^(3+) and Ca^(2+)(e.g.,hematite and Ca(C_(2)O_(4))∙H_(2)O(s))likely occurs during the oxalate precipitation of REEs at relatively high pH(e.g.,pH 2.5),which will reduce rare earth oxalate product *** addition to the metal ions,anionic species,especially SO_(4)^(2-),are also found to negatively affect the precipitation recovery of *** example,when 0.1 mol/L SO_(4)^(2-) occurs in a solution containing 1×10^(−4) mol/L Ce^(3+) and 4×10^(−4) mol/L oxalate,the pH needs to be elevated from 2.0 to 3.3 to achieve the acceptable ***,findings from this study provide guidance for the obtainment of high-purity rare earth products from solutions containing a considerable amount of contaminant metal ions by means of oxalic acid precipitation.

关键词： Rare earth elements Oxalic acid Precipitation Contaminant metal ions

放松训练改善情绪障碍心率变异性的研究进展(综述)

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中国健康心理学杂志 2024年第10期32卷 1472-1477页

作者：严洁睿张文彩王健中国科学院心理研究所北京101408 中国中医科学院广安门医院

自主神经系统的变化是将抑郁、焦虑等情绪障碍与许多身体功能障碍联系起来的核心枢纽,心率变异性是反映自主神经系统活动及平衡的重要指标。本文总结了药物和物理治疗对情绪障碍干预的心率变异性研究,发现具有一定副作用;同时全面地总... 详细信息

自主神经系统的变化是将抑郁、焦虑等情绪障碍与许多身体功能障碍联系起来的核心枢纽,心率变异性是反映自主神经系统活动及平衡的重要指标。本文总结了药物和物理治疗对情绪障碍干预的心率变异性研究,发现具有一定副作用;同时全面地总结了近年通过心率变异性监测已被临床证明有效的全球各类放松训练,发现因较少副作用而受到患者的广泛青睐。未来研究可根据患者的情绪障碍类别、性别、年龄、严重程度和疾病阶段等提供更具个性化和精准度的放松训练,并探索了放松训练与自主神经功能的关系。

关键词：放松训练自主神经系统心率变异性情绪障碍抑郁焦虑

基于改进鲸鱼算法的收卷张力PID控制的性能优化

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辽宁石油化工大学学报 2024年第4期44卷 91-96页

作者：安世硕高海李维军唐静张文才辽宁石油化工大学机械工程学院辽宁抚顺113001 中煤科工集团沈阳研究院有限公司煤矿安全技术国家重点实验室辽宁抚顺113122

PID控制器的参数决定张力控制系统的稳定性和速度,因此研究收卷张力控制中经典PID控制器参数整定优化问题具有重要意义。以卷绕张力系统为切入点,结合PID和改进的鲸鱼优化算法,设计了基于改进鲸鱼算法(L-WOA)的PID张力控制器;为了提高PI... 详细信息

PID控制器的参数决定张力控制系统的稳定性和速度,因此研究收卷张力控制中经典PID控制器参数整定优化问题具有重要意义。以卷绕张力系统为切入点,结合PID和改进的鲸鱼优化算法,设计了基于改进鲸鱼算法(L-WOA)的PID张力控制器;为了提高PID整定参数方法的收敛精度和速度,在进行整定时结合了改进鲸鱼算法;建立数学模型和动态转矩平衡方程,分析了线速度和卷径对卷材张力的影响;分别使用改进鲸鱼算法和其他多种算法进行了参数优化。仿真结果表明,采用改进鲸鱼算法优化PID的控制策略具有响应速度快、控制输出稳定、抗干扰能力强、鲁棒性好等优点。

关键词：恒张力控制 PID参数整定改进鲸鱼优化算法

Realizing the purification and grain refinement of Mg-Gd-Y alloy by one-step flux refining

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Journal of Materials Science & Technology 2024年第6期173卷 202-217页

作者： Xin Tong Guohua Wu Ming Sun Qiman Wang Liang zhang wencai Liu National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China

In the conventional melt preparation of magnesium rare-earth(Mg-RE)alloys,the repeated heating/cooling process involved in grain refinement and flux refining usually prolongs the preparation period and aggravates melt *** this work,the purification and grain refinement of Mg-9Gd-3Y(GW93)alloy was simultaneously realized by one-step refining at 740℃ by using a self-developed compound *** results show that,only after holding for 10 min,the inclusion content of the alloy is reduced by 81%to 0.29%,while the grain size is reduced by 84%to 119μm.A physical model depicting the interactions between compound flux and alloy melt was proposed based on thermodynamic calculation and microstructure *** grain refinement mechanism has been analyzed by considering the presence of Zr particle(Zr_(p))and Zr solute(Zr_(s)).In addition,the generated RECl_(3) was found to be readily absorbed by the flux,decreasing the surface tension and promoting the purification efficacy of the flux,which plays an important role in the promoted elongation of the as-cast Mg-9Gd-3Y-0.5Zr(GW93K)*** work presents a unique prospect in simplifying the melt preparation of Mg-RE alloy with a promoted quality.

关键词： Mg-Gd-Y-Zr alloy Purification Grain refinement Compound flux Settling behavior