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Shear bands of as-cast and semi-solid Ti_(48)Zr_(27)Cu_(6)Nb_(5)Be_(14)bulk metallic glass matrix composites

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China Foundry 2021年第1期18卷 75-82页

作者： Xin-hua Huang Lin-hao Zhu Hong-min Guo Hua-lan Jin xiang-jie yang School of Mechanical and Electrical Engineering Nanchang UniversityNanchang330031China Key Laboratory of Near Net Forming in Jiangxi Province Nanchang UniversityNanchang330031China School of Material Science and Engineering Nanchang UniversityNanchang330031China Hunan Province Special Equipment Inspection and Research Institute Changsha410117China

The as-cast Ti_(48)Zr_(27)Cu_(6)Nb_(5)Be_(14)bulk metallic glass matrix composites(BMGMCs)were fabricated using a copper mold suction casting ***,the semi-solid BMGMC samples were obtained following an isothermal treatment(heating at 900°C for 10 min,then cooling with water).The microstructure and compression property were investigated by scanning electronic microscopy(SEM)and universal mechanical *** a result of the isothermal treatment,the crystal shapes change from fine,granular,and dendritic to spherical or vermicular,and the average crystal size of the as-cast and semi-solid samples is 2.2μm and 18.1μm,*** plasticity increases from 5.31%in the as-cast to 10.23%in the semi-solid samples,with an increase of 92.66%.The shear bands from different areas of the side surfaces of as-cast and semisolid compression fracture samples were *** characteristic changes of multiplicity,bend,branch and intersection of shear bands in different areas indicate that the deformation of as-cast and semi-solid samples is non-uniform during *** is found that poor plasticity of the as-cast samples or good plasticity of the semi-solid samples are reflected by characteristics of the shear *** semi-solid isothermal treatment improves the plasticity by forming large crystals which can block the expansion of shear bands and promote the multiplicity of shear bands.

关键词： shear bands Ti_(48)Zr_(27)Cu_(6)Nb_(5)Be_(14) as-cast semi-solid plasticity

Effects of Cooling Rate and Component on the Microstructure and Mechanical Properties of Mg–Zn–Y Alloys

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Acta Metallurgica Sinica(English Letters) 2015年第1期28卷 7-14页

作者： Shuang Shao Yong Liu Chun-Shui Xu Ying-Xuan Xu Bin Wu Xiao-Shu Zeng Xian-Feng Lu xiang-jie yang Key Laboratory of Near Net Forming of Jiangxi Province Nanchang University

The microstructure and mechanical properties of Mg–6Zn–1Y and Mg–6Zn–3Y（wt%） alloys under different cooling rates were investigated. The results show that the second dendrite arm spacing（SDAS） of Mg–6Zn–1Y and Mg–6Zn–3Y is reduced by 32 and 30% with increasing cooling rates（Rc） from 10.2 to 23 K/s, which can be predicted using a empirical model of SDAS=68 R 0：45：45cand SDAS=73 R 0c, respectively. The compressive strength of both alloys increases with increasing the cooling rate, which is attributed to the increase of volume fraction（Vf） of secondary phases under high cooling rate. The interaction of the cooling rate and component with SDAS has been theoretically analyzed using interdependence theory.

关键词： Mg–Zn–Y alloys Microstructural characterization Compressive strength Cooling rate Interdependence theory

Atomic relaxation,stability and electronic properties of Mg2Sn(100)surfaces from ab-initio calculations

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Journal of Magnesium and Alloys 2016年第1期4卷 62-67页

作者： Hui Ren Wen-Cheng Hu De-Jiang Li Xiao-Qin Zeng Xue yang Xiao-Shu Zeng xiang-jie yang Bolong Huang Yong Liu Key Laboratory of Near Net Forming of Jiangxi Province Nanchang UniversityNanchang 330031China National Engineering Research Center of Light Alloys Net Forming Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratories of Metal Matrix Composite Shanghai Jiao Tong UniversityShanghai 200240China Department of Physics and Materials Science City University of Hong KongKowloonHong Kong

Mg2Sn(100)surfaces were investigated using ab-initio method based on density functional theory in order to explore the surface *** is found that both the eleven-layers for Mg-termination surfaces and the nine-layers for Sn-termination surfaces are all converged very *** effects of relaxation mainly occurred within the three outermost atomic layers for both Mg and Sn terminations during the surface ***-termination surfaces are more stable than Sn-termination surfaces according to the analysis of surface *** density of states reveals the metallic property of both Mg-termination and Sn-termination *** bonding exists in Mg2Sn(100)surfaces according to the analysis of partial density of states.

关键词： Magnesium alloy Ab-initio calculation Surface energy Surface stability Electronic properties

Phase field lattice Boltzmann model for non-dendritic structure formation in aluminum alloy from LSPSF machine

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Transactions of Nonferrous Metals Society of China 2020年第3期30卷 559-570页

作者： An-shan YU xiang-jie yang Hong-min GUO School of Mechanical and Electrical Engineering Nanchang UniversityNanchang 330031China Key Laboratory of Near Net Forming in Jiangxi Province Nanchang 330031China School of Materials Science and Engineering Nanchang UniversityNanchang 330031China

The formation of non-dendritic structures in the primary phase of an aluminum alloy solidified using low superheat pouring with a shearing field(LSPSF) machine was investigated by numerical *** growth and motion of a dendrite during solidification was simulated by a combination of the lattice Boltzmann method and the phase field *** simulation results indicated that enough shear flow helped homogenize the concentration fields,rotate crystals and altere microstructures from dendritic to *** interaction of grains was also discussed.A fragmentation criterion was established based on partial remelting of dendrite arms;fragmentation was enhanced by a strong shear flow and larger inclined *** simulation results were verified experimentally.

关键词： numerical simulation non-dendritic structure low superheat pouring with shearing field(LSPSF) aluminum alloy phase field method lattice Boltzmann method

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科技期刊中3个与范围有关的问题

吉首大学学报（社会科学版） 2010年第3期31卷 139-141页

作者：向阳洁吉首大学学报编辑部湖南吉首416000

科技期刊中描述范围时应规范使用浪纹线和一字线,表示起止作用时,浪纹线是数值范围符号,而一字线用于连接地名或方位名词,或相关的时间.英文论文中连接序号范围的是连接号"-"和"from…to…".在描述变量取值范围时,建议在有2个变量且为... 详细信息

科技期刊中描述范围时应规范使用浪纹线和一字线,表示起止作用时,浪纹线是数值范围符号,而一字线用于连接地名或方位名词,或相关的时间.英文论文中连接序号范围的是连接号"-"和"from…to…".在描述变量取值范围时,建议在有2个变量且为同一取值范围的情况下,分开各自用数学运算符连接或用区间表示更简洁。

关键词：数值范围序号范围符号取值范围建议

Identification of a dual functional betulinic acid analog for the treatment of osteoarthritis by phenotypic screening

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Science China Life Sciences 2025年第1期 300-302页

作者： Ze-Min Lin Mai xiang Wen-Hui Wei Shu-Hui Fan Li Chen jie Wang Xiao-Qian yang Chun-Hao yang Shi-Jun He Jian-Ping Zuo Laboratory of Immunopharmacology State Key Laboratory of Drug ResearchShanghai Institute of Materia MedicaChinese Academy of Sciences School of Pharmacy University of Chinese Academy of Sciences School of Pharmacy Nanjing University of Chinese Medicine State Key Laboratory of Drug Research Department of Medicinal ChemistryShanghai Institute of Materia MedicaChinese Academy of Sciences Innovation Research Institute of Traditional Chinese Medicine Shanghai University of Traditional Chinese Medicine Experiment Center for Science and Technology Shanghai University of Traditional Chinese Medicine

Dear Editor, Phenotypic drug discovery, which observes compound effects on physiology,has given way to targeting specific molecules, but has revived by using modern methods to find drugs based on therapeutic outcomes in disease models(Vincent et al., 2022). Osteoarthritis(OA) is a prevalent chronic joint disorder, primarily affecting knee joints, with osteoclast activation due to low-grade inflammation resulting in increased bone resorption and structural changes in the joint(Katz et al.,2021).

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同方期刊数据库

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数理公式中括号表示运算顺序时的使用建议

衡阳师范学院学报 2010年第6期31卷 158-159页

作者：向阳洁吉首大学学报编辑部湖南吉首416000

鉴于国家标准仅对文字语言中圆括号的使用作了阐述,为避免在数理公式中使用括号时出现错误,通过列举实例分情况着重分析讨论了数理公式中括号表示运算顺序时如何规范添加和套用,并提出几点建议。

关键词：数理公式括号运算顺序使用

Grain refinement of Al-5%Cu aluminum alloy under mechanical vibration using meltable vibrating probe

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Transactions of Nonferrous Metals Society of China 2014年第8期24卷 2489-2496页

作者：郭洪民章爱生杨湘杰严明明南昌大学材料科学与工程学院南昌330031 南昌大学江西省高性能精确成形重点实验室南昌330031

A mechanical vibration technique to refine solidified microstructure was reported. Vibration energy was directly introduced into a molten alloy by a vibrating horn, and the vibrating horn was melted during vibration. Effects of vibration acceleration and mass ratio on the microstructure of Al-5% Cu alloy were investigated. Results show that the present mechanical vibration could provide localized cooling by extracting heat from the interior of molten alloy, and the cooling rate is strongly dependent on vibration acceleration. It is difficult to refine the solidified microstructure when the treated alloy keeps full liquid state within the entire vibrating duration. Significantly refined microstructure was obtained by applying mechanical vibration during the initial stage of solidification. Moreover, mechanisms of grain refinement were discussed.

关键词： Al-Cu alloy grain refinement solidification mechanical vibration

Output Feedback Stabilization of an Unstable Wave Equation with Observations Subject to Time Delay

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Journal of Systems Science & Complexity 2016年第1期29卷 99-118页

作者： yang Kunyi REN xiang ZHANG jie College of Science North China University of Technology

This paper focuses on boundary stabilization of a one-dimensional wave equation with an unstable boundary condition,in which observations are subject to arbitrary fixed time *** observability inequality indicates that the open-loop system is observable,based on which the observer and predictor are designed:The state of system is estimated with available observation and then predicted without *** that equivalently the authors transform the original system to the well-posed and exponentially stable system by backstepping *** equivalent system together with the design of observer and predictor give the estimated output *** is shown that the closed-loop system is exponentially *** simulations are presented to illustrate the effect of the stabilizing controller.

关键词： Exponential stability observability inequality output feedback unstable boundary condition time delay wave equation