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Microstructure and texture evolution in fully pearlitic steel during wire drawing

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Science China(Technological Sciences) 2013年第5期56卷 1139-1146页

作者： GUO Ning LUAN BaiFeng wang bingshu LIU Qing Department of Materials Science and Engineering Southwest University Department of Materials Science and Engineering Chongqing University Department of Materials Science and Engineering Fuzhou University

The evolution of morphology of pearlite and crystallographic texture of ferrite matrix in fully pearlitic steels during wire drawing were quantitatively investigated. The study revealed that a fiber structure of the pearlite morphology and a 〈110〉 fi- ber texture of the ferrite matrix begin to take shape and develop gradually with increasing strain. The growth rates of the fiber structure and the 〈110〉 texture are different in different regions within the wires with increasing drawing strain. There is a close relationship between the pearlite morphology and the crystalline texture during wire drawing. The pearlite interlamellar spacing （ILS） and thickness of cementite lamellae （To） decrease gradually both in longitudinal and transverse sections. The definition of pearlite colony should be reconsidered for describing microstructure of the wire drawing deformed pearlitic steels.

关键词： pearlitic steel wire drawing microstructure texture

课程思政背景下环境科学概论课程教学改革探索

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大学教育 2024年第10期 94-99页

作者：张良清邱佳容汪炳叔福州大学先进制造学院福建晋江362251

环境科学概论课程是环境科学类专业的基础课,在培养环境专业人才方面发挥着重要作用。在专业课程教学过程中,适当融入契合度高的思政元素,是课程思政背景下教学改革的关键所在。课程组深入挖掘了环境科学概论中蕴含的思政元素,并进行了... 详细信息

环境科学概论课程是环境科学类专业的基础课,在培养环境专业人才方面发挥着重要作用。在专业课程教学过程中,适当融入契合度高的思政元素,是课程思政背景下教学改革的关键所在。课程组深入挖掘了环境科学概论中蕴含的思政元素,并进行了整体融入设计。文章围绕课程的建设、课程思政理念与教学目标的确定、课程思政元素的挖掘与融入、考核评价体系的构建、教学反思等方面,探索对环境科学概论课程进行全面改革,以实现环境专业知识与思政元素的有机融合,落实立德树人的根本任务。

关键词：课程思政环境科学概论教学目标思政融入方法教学改革

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Simulation of texture evolution and deformation mechanism in Mg-3Al-1Zn alloy during uniaxial compression

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Science China(Technological Sciences) 2015年第12期58卷 2052-2059页

作者： YAO JinYi wang bingshu DENG LiPing CHAPUIS Adrien LI Qiang LIU Qing College of Materials Science and Engineering Fuzhou University College of Materials Science and Engineering Chongqing University

The effects of starting texture on he flow curves, and microstructure and texture evolutions of AZ31(Mg-3Al-1Zn-0.3Mn in wt.%) alloy during uniaxial compression at room temperature have been investigated by experiments and simulations. Two kinds of cylindrical compression samples were cut from the AZ31 extruded rod: one was cut with the compression direction parallel to the extruded direction(ED), and the other was cut with the compression axis perpendicular to the ED. The samples were termed as C//ED sample and C⊥ED sample, respectively. The results indicate that the general characteristics of flow curves and texture evolutions in both C⊥ED and C//ED samples during compression can be well explained by the relative activities of deformation mechanisms, which show a strong orientation dependence on the initial textures and the current texture. A significant yield behavior can be induced by {10-12} twinning at the starting deformation, and the lower yield stress in C⊥ED sample can be enhanced by the high activity of basal slip. The work hardening behavior is related to the activities of basal slip, pyramidal slip, {10-12} twinning, as well as {10-11} twinning. However, the activity of prismatic slip is insensitive to the starting texture, and mostly negligible in all samples.

关键词： magnesium alloy EBSD twinning crystal plasticity

Examination of dynamic recrystallization during compression of AZ31 magnesium

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Science China(Technological Sciences) 2009年第1期52卷 176-179页

作者： XIN RenLong wang bingshu CHEN XingPin HUANG GuangJie LIU Qing College of Material Science and Engineering Chongqing UniversityChongqing 400030China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400030China

This study aimed to investigate dynamic recrystallization (DRX) behavior during compression of magnesium alloy AZ31. Cylinder samples were cut from the extruded rod and hot rolled sheet AZ31 for compression test. The samples were compressed using a Gleeble 1500D at a temperature of 300°C and a strain rate of 0.01 s?1. Grain orientations and misorientation angles across grain boundaries for the tested samples were obtained by using electron backscatter diffraction (EBSD) technique. The results showed that strong basal texture was observed after 50% compression (ε = 0.69) on both the extruded and hot rolled samples, which have different initial textures. It was observed that with increased strain, DRX grains gradually rotated to basal orientation, and grain boundaries with misorientation angle of near 30° was formed in the samples. At the strain of 0.69, a high fraction of high-angle (> 60°) boundaries was present in the extruded sample, whereas almost no high angle boundaries were observed in the hot rolled sheet sample.

关键词： magnesium alloy dynamic recrystallization EBSD misorientation

信息类专业数据结构课程思政建设教学探索与实践

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软件导刊 2024年第9期23卷 209-213页

作者：王兵书吴瑕李强马春燕西北工业大学软件学院陕西西安710129

为解决信息类专业数据结构课程在思政建设方面存在的“硬融入”“表面化”等问题,根据《高等学校课程思政建设指导纲要》中对工科学生培养的要求,从工程伦理教育、大国工匠精神、家国情怀和使命担当等角度深入挖掘数据结构相关的课程思... 详细信息

为解决信息类专业数据结构课程在思政建设方面存在的“硬融入”“表面化”等问题,根据《高等学校课程思政建设指导纲要》中对工科学生培养的要求,从工程伦理教育、大国工匠精神、家国情怀和使命担当等角度深入挖掘数据结构相关的课程思政元素,并将其融入到专业课教学中。实践结果表明,课程思政改革后学生对专业知识点的把握更加清晰,学习兴趣更加浓厚,达到了润物无声的育人效果。所提思政元素亦可为信息类专业其他课程的思政教学提供参考。

关键词：课程思政数据结构信息类专业教学案例

Effects of conductive agent type on lithium extraction from salt lake brine with LiFePO_(4) electrodes

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 678-687页

作者： Zhen Zhang Pan Luo Yan Zhang Yuhan wang Li Liao Bo Yu Mingshan wang Junchen Chen bingshu Guo Xing Li School of New Energy and Materials Southwest Petroleum UniversityChengdu 610500China Energy Storage Research Institute Southwest Petroleum UniversityChengdu 610500China

Electrochemical lithium extraction from salt lakes is an effective strategy for obtaining lithium at a low ***,the elevated Mg:Li ratio and the presence of numerous coexisting ions in salt lake brines give rise to challenges,such as prolonged lithium extraction periods,diminished lithium extraction efficiency,and considerable environmental *** this work,Li FePO4(LFP)served as the electrode material for electrochemical lithium *** conductive network in the LFP electrode was optimized by adjusting the type of conductive *** approach resulted in high lithium extraction efficiency and extended cycle *** the single conductive agent of acetylene black(AB)or multiwalled carbon nanotubes(MWCNTs)was replaced with the mixed conductive agent of AB/MWCNTs,the average diffusion coefficient of Li+in the electrode increased from 2.35×10^(-9)or 1.77×10^(-9)to 4.21×10^(-9)cm^(2)·s^(-1).At the current density of 20 mA·g^(-1),the average lithium extraction capacity per gram of LFP electrode increased from 30.36 mg with the single conductive agent(AB)to 35.62 mg with the mixed conductive agent(AB/MWCNTs).When the mixed conductive agent was used,the capacity retention of the electrode after 30 cycles reached 82.9%,which was considerably higher than the capacity retention of 65.8%obtained when the single AB was ***,the electrode with mixed conductive agent of AB/MWCNTs provided good cycling *** the conductive agent content decreased or the loading capacity increased,the electrode containing the mixed conductive agent continued to show excellent electrochemical ***,a self-designed,highly efficient,continuous lithium extraction device was *** electrode utilizing the AB/MWCNT mixed conductive agent maintained excellent adsorption capacity and cycling performance in this *** work provides a new perspective for the electrochemical extraction of lithium using LFP electrodes.

关键词： salt lake brine lithium extraction electrochemical lithium extraction conductive agent extraction efficiency adsorption capacity

混凝土轴压受载声发射特征及失稳演化过程研究

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工业建筑 2024年第2期54卷 161-166页

作者：杨亚晗于泽明李参天朱成发王炳树张春会于志兵欧阳韦张新为北京科技大学北京100083 北京建筑材料检验研究院股份有限公司北京100041 北京建筑材料科学研究总院有限公司北京100041 华北水利水电大学郑州450045 河北科技大学石家庄050018 四川省交通建设集团有限责任公司成都610047 中电建路桥集团有限公司北京100044 中建路桥集团有限公司石家庄050000

桥梁桩基混凝土承受轴向压载过大,其内部破坏开裂过程会释放弹性波,为量化压载失稳演化过程特征,通过现场原位钻取桥梁桩基结构芯样,采用轴向压载与声发射同步监测试验,研究混凝土试件加载全过程声发射时空演化特征,分析混凝土材料压载... 详细信息

桥梁桩基混凝土承受轴向压载过大,其内部破坏开裂过程会释放弹性波,为量化压载失稳演化过程特征,通过现场原位钻取桥梁桩基结构芯样,采用轴向压载与声发射同步监测试验,研究混凝土试件加载全过程声发射时空演化特征,分析混凝土材料压载失稳破坏全过程与声发射振铃计数、能量释放、震源定位等表征参数的演化关系,获得加载过程与声发射特征关联性的定量描述,分析其失稳演化过程。研究结果表明:轴向压载条件下混凝土试件的应力与声发射振铃计数、能量释放随时间的变化规律具有一致性,声发射定位点主要在剪应力集中区形成宏观“定位带”与混凝土裂缝发展及破坏表现一致,可根据声发射事件活跃度量化判断混凝土受载阶段,反映混凝土失稳临界特征,对桩基混凝土服役监测具有重要意义。

关键词：桩基混凝土声发射特征振铃计数能量失稳演化过程

Fluorinated poly(fluorenyl ether)s with linear multi-cationic side chains for vanadium redox flow batteries

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Science China Materials 2021年第2期64卷 349-361页

作者： Yu Chen Yanyan Li bingshu wang Meijin Lin Zailai Xie Dongyang Chen College of Materials Science and Engineering Fuzhou UniversityFuzhou350116China College of Chemistry Fuzhou UniversityFuzhou350116China

The cationic group distribution along the polymeric backbones of anion exchange membranes(AEMs)has significant influence on their microscopic morphology and anion *** develop high-performance AEMs for vanadium redox flow batteries(VRFBs),a series of poly(fluorenyl ether)samples bearing di-and tri-quaternary ammonium side chains with similar ion exchange capacities(IECs)were synthesized by grafting cationic alkyl chains with tertiary amine-containing poly(fluorenyl ether)*** experimental results indicate that the introduction of the multi-cationic side chains facilitates the formation of micro-phase-separated morphologies and enhances anion ***,the number of spacer atoms between the quaternary ammonium groups on the side chains affects the water uptake of the membranes,thus complicating the relationship between the density of cationic group distribution and anion *** poly(fluorenyl ether)s with dicationic side chains and six spacing atoms(DQA-PFE-C6)showed the highest anion conductivity.A VRFB assembled with DQA-PFE-C6 exhibited a maximum power density of 239.80 mW cm^−2 at 250 mA cm^−2,which is significantly higher than a VRFB assembled with Nafion ***,side chain engineering is an effective chemical approach to enhance the properties of AEMs for VRFB applications.

关键词： anion exchange membranes side chain engineering phase separation Coulombic repulsion vanadium redox flow batteries

Unraveling high efficiency multi-step sodium storage and bidirectional redox kinetics synergy mechanism of cobalt-doping vanadium disulfide anode

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Journal of Energy Chemistry 2024年第7期94卷 148-157页

作者： Enzhi Li Mingshan wang Yuanlong Feng Lin Yang Qian Li Zhenliang Yang Junchen Chen Bo Yu bingshu Guo Zhiyuan Ma Yun Huang Jiangtao Liu Xing Li School of New Energy and Materials Southwest Petroleum UniversityChengdu 610500SichuanChina Institute of Materials China Academy of Engineering PhysicsMianyang 621908SichuanChina State Key Laboratory of Advanced Chemical Power Sources Guizhou Meiling Power Sources Co.Ltd.Zunyi 563003GuizhouChina school of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001HeilongjiangChina

Sodium-based storage devices based on conversion-type metal sulfide anodes have attracted great atten-tion due to their multivalent ion redox reaction ***,they also suffer from sodium polysul-fides(NaPSs)shuttling problems during the sluggish Na^(+) redox process,leading to"voltage failure"and rapid capacity ***,a metal cobalt-doping vanadium disulfide(Co-VS_(2))is proposed to simulta-neously accelerate the electrochemical reaction of VS_(2) and enhance the bidirectional redox of soluble *** is found that the strong adsorption of NaPSs by V-Co alloy nanoparticles formed in situ during the conversion reaction of Co-VS_(2) can effectively inhibit the dissolution and shuttle of NaPSs,and ther-modynamically reduce the formation energy barrier of the reaction path to effectively drive the complete conversion reaction,while the metal transition of Co elements enhances reconversion kinetics to achieve high ***,Co-VS_(2) also produce abundant sulfur vacancies and unsaturated sulfur edge defects,significantly improve ionic/electron diffusion ***,the Co-VS_(2) anode exhibits ultrahigh rate capability(562 mA h g^(-1) at 5 A g^(-1)),high initial coulombic efficiency(~90%)and 12,000 ultralong cycle life with capacity retention of 90%in sodium-ion batteries(SIBs),as well as impressive energy/power density(118 Wh kg^(-1)/31,250 W kg^(-1))and over 10.000 stable cycles in sodium-ion hybrid capacitors(SIHCs).Moreover,the pouch cell-type SIHC displays a high-energy density of 102 Wh kg^(-1) and exceed 600 stable *** work deepens the understanding of the electrochemical reaction mechanism of conversion-type metal sulfide anodes and provides a valuable solution to the shuttlingofNaPSs inSIBsandSIHCs.

关键词： Sodium-ionbatteries Sodium-ion hybrid capacitors Pouch cells Vanadium disulfide Shuttle effect