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Spheroidizing Behavior and Spheroidizing Kinetics of W-phase During Solid-Solution Treatment in Mg–Zn–Y–Mn–(B)Alloys

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Acta Metallurgica Sinica(English Letters) 2017年第5期30卷 464-469页

作者： Kai Yang Jin-Shan Zhang Xi-Mei Zong Wei Liu chun-xiang xu College of Materials Science and Engineering TaiyuanUniversity of Technology Taiyuan 030024 China Shanxi Key Laboratory of Advanced Magnesium-based Materials Taiyuan 030024China

The spheroidizing mechanism of W-phase in the Mg–Zn–Y–Mn–（B） alloys during solid-solution treatment was investigated by using kinetic methodologies. The microstructure and mechanical properties of heat-treated Mg_（94）Zn_（2.5）-Y_（2.5）Mn_1 alloy containing 0.003 wt% B were compared with heat-treated Mg_（94）Zn_（2.5）-Y_（2.5）Mn_1 alloy. The heat-treated Mg_（94）Zn_（2.5）-Y_（2.5）Mn_1 alloy with 0.003 wt% B contained fine and uniform W-phase particles, which exhibited optimal mechanical performance. The ultimate tensile strength, yield strength and elongation were 287.7, 125.5 MPa and 21.1%,respectively.

关键词： Magnesium alloys W-phase Spheroidizing Kinetics Microstructure Mechanical properties

Effect of Precipitated Phases on Corrosion of Mg95.8Gd3Zn1Zr0.2 Alloy with Long-Period Stacking Ordered Structure

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Acta Metallurgica Sinica(English Letters) 2016年第1期29卷 32-38页

作者： Xi-Mei zong Dan Wang Wei Liu Kai-Bo Nie chun-xiang xu Jin-Shan Zhang College of Materials Science and Engineering Taiyuan University of Technology Taiyuan 030024 China Shanxi Key Laboratory of Advanced Magnesium-Based Materials Taiyuan 030024 China Department of Chemistry Taiyuan Normal UniversityTaiyuan 030031 China

The microstructure of the precipitated phases of ***3Zn1Zro.2 alloys with long-period stacking ordered structure before and after heat treatment is discussed. The corrosion properties of the as-cast （F）, solid-solution （T4） and aging-treated （T6） alloys in 1% NaC1 solution are studied. The hydrogen evolution and electrochemical measurements display that the as-cast ***3Zn1Zro.2 alloy with the continuous network eutectic phase exhibits the greatest corrosion resistance, while T6 sample with some needle-like phases and the particle phases is the worst among the three alloys. It is proposed to be mainly related to the amount, composition, microstructure and distribution of the precipitated phases.

关键词： Mg-Gd-Zn Corrosion properties Long-period stacking ordered (LPSO) Microstructure

Compressive deformation behavior of an indirect-extruded Mg-8Sn-1Al-1Zn alloy

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International Journal of Minerals,Metallurgy and Materials 2013年第1期20卷 49-56页

作者： Wei-li Cheng Zhong-ping Que Jin-shan Zhang chun-xiang xu Wei Liang Bong Sun You Sung Soo Park School of Materials Science and Engineering Taiyuan University of Technology Korea Institute of Materials Science Ulsan National Institute of Science and Technology

The medium and warm deformation behaviors of an indirect-extruded Mg-8Sn-IAI-IZn alloy were investigated by compression tests at temperatures between 298 and 523 K and strain rates of 0.001-10 s-1. It was found that the twinning-slip transition temperature was strain rate dependent, and all the true stress-true strain curves could be divided into two groups： concave and convex curves. Associated microstructural investigations indicated that the dynamic recrystallization （DRX） be- havior of the alloy varied with deformation conditions. At high strain rate and low temperature, dynamically recrystallized grains preferentially nucleated and developed in the twinned regions, indicating that twinning-induced DRX was dominant. While, at low strain rate, DRX developed extensively at grain boundaries and twins, and the process of twinning contributed to both oriented nucleation and selective growth. For the studied alloy, cracks mainly initiated from the shear band and twinning lamellar over the ranges of temperature and strain rate currently applied.

关键词： magnesium alloys compression testing dynamic recrystallization microstructure

Effect of Li on formation of long period stacking ordered phases and mechanical properties of Mg-Gd-Zn alloy

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China Foundry 2016年第4期13卷 256-261页

作者： Li-yun Wei Jin-shan Zhang Wei Liu chun-xiang xu Zhi-yong You Kai-bo Nie College of Materials Science and Engineering Taiyuan University of Technology Taiyuan 030024 China Shanxi Key Laboratory of Advanced Magnesium-based Materials Taiyuan 030024 China

Alloys with composition of Mg_(96-x)Gd_3Zn_1Li_x(at.%)(x=0, 2, 4, and 6) were prepared by conventional casting. The microstructures of these alloys under as-cast and solid-solution conditions have been observed, and the mechanical properties were investigated. The results showed that Li is an effective element to refine the grains and break the eutectic networks in as-cast MgGd_3Zn_1 alloy. During solid solution treatment, these broken eutectic networks are spheroidized and highly dispersed. In addition, plentiful lamellar long period stacking ordered(LPSO) phases are precipitated in an α-Mg matrix when the Li addition is not more than 4%. Solid-solution treated Mg_(92)Gd_3Zn_1Li_4 alloy exhibits an optimal ultimate tensile strength(UTS) of 226 MPa and elongation of 5.8%. The strength of MgGd_3Zn_1 alloy is improved significantly, meanwhile, the toughness is apparently increased.

关键词： Mg-Gd-Zn alloys Li second phase long period stacking ordered phase comprehensive properties

Microstructure and mechanical properties of a compound reinforced Mg95Y2.5Zn2.5 alloy with long period stacking ordered phase and W phase

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China Foundry 2017年第1期14卷 34-38页

作者： Shou-zhong Wu Jin-shan Zhang chun-xiang xu Kai-bo Nie Xiao-feng Niu Zhi-yong You College of Materials Science and Engineering Taiyuan University of TechnologyTaoyuan 030024China Shanxi Key Laboratory of Advanced Magnesium-based Materials Taiyuan 030024China

The microstructure evolution of Mg100-2xYxZnx （x=2, 2.5, 3, 3.5） alloys was investigated. Results show that the Mg100-2xYxZnx alloys are composed of a-Mg, long period stacking ordered （LPSO） phase and eutectic structure phase （W phase）, and the Mg95Y2.5Zn2.5 alloy has the best comprehensive mechanical properties. Subsequently, the microstructure evolution of the optimized alloy Mg95Y2.5Zn2.5 during solidification and heat treatment processes was analyzed and discussed by means of OM, SEM, TEM, XRD and DTA. After heat treatment, the lamellar phase 14H-LPSO precipitated in a-Mg and W phase transforms into particle phase （MgyZn2）. Due to the compound reinforcement effect of the particle phase and LPSO phase （18R＋14H）, the mechanical properties of the alloy are enhanced. The tensile strength and elongation of the Mg95Y2.5Zn2.5 alloy is improved by 9.1% and 31.3% to 215 MPa and 10.5%, respectively, after solid-solution treatment.

关键词： magnesium alloys Mg95Y2.5Zn2.5 alloy long period stacking ordered (LPSO) W phase compound reinforcement

Mitophagy in acute central nervous system injuries:regulatory mechanisms and therapeutic potentials

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Neural Regeneration Research 2025年第9期20卷 2437-2453页

作者： Siyi xu Junqiu Jia Rui Mao xiang Cao Yun xu Department of Neurology Nanjing Drum Tower HospitalClinical College of Jiangsu UniversityNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalChinese Academy of Medical Science&Peking Union Medical CollegeNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingJiangsu ProvinceChina State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases Nanjing UniversityNanjingJiangsu ProvinceChina Jiangsu Key Laboratory for Molecular Medicine Medical School of Nanjing UniversityNanjingJiangsu ProvinceChina Nanjing Neurology Medical Center NanjingJiangsu ProvinceChina

Acute central nervous system injuries,including ischemic stro ke,intracerebral hemorrhage,subarachnoid hemorrhage,traumatic brain injury,and spinal co rd injury,are a major global health *** optimal therapies and improving the long-term neurological functions of patients with acute central nervous system injuries are urgent *** are susceptible to damage after acute central nervous system injury,and this leads to the release of toxic levels of reactive oxygen species,which induce cell ***,a selective form of autophagy,is crucial in eliminating redundant or damaged mitochondria during these *** evidence has highlighted the significant role of mitophagy in acute central nervous system *** this review,we provide a comprehensive overview of the process,classification,and related mechanisms of *** also highlight the recent developments in research into the role of mitophagy in various acute central nervous system injuries and drug therapies that regulate *** the final section of this review,we emphasize the potential for treating these disorders by focusing on mitophagy and suggest future research paths in this area.

关键词： autophagy intracerebral hemorrhage ischemic stroke mitochondria mitochondrial biogenesis mitochondrial quality control mitophagy spinal cord injury subarachnoid hemorrhage traumatic brain injury

Risk factors for biometry prediction error by Barrett Universal II intraocular lens formula in Chinese patients

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International Journal of Ophthalmology(English edition) 2025年第1期18卷 74-78页

作者： xu-Hao Chen Ying Hong xiang-Han Ke Si-Jia Song Yu-Jie Cen chun Zhang Beijing Key Laboratory of Restoration of Damaged Ocular Nerve Department of OphthalmologyPeking University Third HospitalBeijing 100191China State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangdong Provincial Key Laboratory of Ophthalmology and Visual ScienceGuangzhou 510060Guangdong ProvinceChina

AIM:To investigate the influence of postoperative intraocular lens(IOL)positions on the accuracy of cataract surgery and examine the predictive factors of postoperative biometry prediction errors using the Barrett Universal II(BUII)IOL formula for ***:The prospective study included patients who had undergone cataract surgery performed by a single surgeon from June 2020 to April *** collected data included the best-corrected visual acuity(BCVA),corneal curvature,preoperative and postoperative central anterior chamber depths(ACD),axial length(AXL),IOL power,and refractive *** formula was used to calculate the IOL *** mean absolute error(MAE)was calculated,and all the participants were divided into two groups *** t-tests were applied to compare the variables between *** regression analysis was used to analyze the influence of age,AXL,corneal curvature,and preoperative and postoperative ACD on ***:A total of 261 patients were *** 243(93.1%)and 18(6.9%)had postoperative MAE1 D,*** number of females was higher in patients with MAE>1 D(χ^(2)=3.833,P=0.039).The postoperative BCVA(logMAR)of patients with MAE>1 D was significantly worse(t=-2.448;P=0.025).After adjusting for gender in the logistic model,the risk of postoperative refractive errors was higher in patients with a shallow postoperative anterior chamber[odds ratio=0.346;95% confidence interval(CI):0.164,0.730,P=0.005].CONCLUSION:Risk factors for biometry prediction error after cataract surgery include the patient’s sex and postoperative *** with a shallow postoperative anterior chamber are prone to have refractive errors.

关键词： intraocular lens power calculation gender anterior chamber depth biometry prediction error

Numerical simulation of microstructure and microporosity morphology in directional solidification of aluminum-copper alloys:Effect of copper content and withdrawal rate

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China Foundry 2025年第1期22卷 33-44页

作者： Wei Yuan Hai-dong Zhao xu Shen chun Zou Yuan Liu Qing-yan xu National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640China Key Laboratory for Advanced Materials Processing Technology(Ministry of Education) Tsinghua UniversityBeijing 100084China

Microporosity formed in the solidification process of Al alloys is detrimental to the alloy properties.A two-dimensional cellular automaton(CA)model was developed to simulate the microstructure and microporosity formation in Al-Cu alloys,considering variations in Cu content and solidification *** results indicate that the Cu content primarily influences the growth of *** validate the model,directional solidification experiments were conducted on Al-Cu alloys with varing Cu contents and withdrawal *** experimental results of dendrites and microporosity characteristics agree well with the predictions from the developed model,thus confirming the validity of the *** alloy’s liquidus temperature,dendrite morphology,and hydrogen saturation solubility arising from different Cu contents have significant effects on microporosity *** withdrawal rate primarily affects the nucleation of hydrogen microporosity by altering cooling rates and dendritic growth rates,resulting in different microporosity characteristics.

关键词： microporosity dendrites cellular automaton Al-Cu alloys directional solidification

Unraveling atomistic and electronic origins of multiaxial magnetic anisotropy

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 175-182页

作者： Boyu Liu xueyang Li Junsheng Feng Changsong xu Hongjun xiang Key Laboratory of Computational Physical Sciences(Ministry of Education) Institute of Computational Physical SciencesState Key Laboratory of Surface Physics and Department of PhysicsFudan UniversityShanghai200433China Shanghai Qi Zhi Institute Shanghai200030China School of Physics and Material Engineering Hefei Normal UniversityHefei230601China

Multiaxial magnetic anisotropy(MA)refers to the phenomenon that multiple axes of the magnetic crystal correspond to different energy *** with the common uniaxial magnetic anisotropy,multiaxial MA facilitates novel forms of applications in ***,by combining the first-principles-based spin Hamiltonian and tight-binding(TB)method,we reveal the microscopic origins,instead of the common phenomenological understanding,of biaxial MA and triaxial *** the example system of NiO,it is found that the multiple minima result from the fourth-order and the sixth-order single ion interactions,while the difference between[110]and[110]directions originates from a second-order bond-dependent anisotropic pair interaction(i.e.,the so-called Gamma interaction).Moreover,through the application of a newly developed general spin dependent TB approach,it is revealed that the triaxial MA arises from the special spin-orbital entangled Hund term,which is different from the orbital-independent Hund term in the usual Slater Koster TB *** work thus not only leads to a thorough understanding of the multiaxial MA in NiO,but also establishes a methodology that can be widely used to explore the microscopic origins of MA in different magnets.

关键词： multiaxial magnetic anisotropy origin of multiaxial magnetic mnisotropy effective spin Hamiltonian tight-binding model antiferromagnetism