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Rare Metals 2023年第8期42卷 2774-2780页

作者： xiao-yun song Yan Li Fei Zhang State Key Laboratory of Nonferrous Metals and Processes GRIMAT Engineering Institute Co.LtdBeijing 101407China School of Materials Science and Engineering Beihang UniversityBeijing 100191China

The effects of solution and aging heat treatment on microstructural evolution and room temperature tensile properties for as-forged Ni-45Ti-5Al-2Nb-1Mo alloy were investigated through scanning electron microscopy(SEM),transmission electron microscopy(TEM)and tensile *** results show that the microstructure of solution-treated alloy comprises NiTi matrix,Ti_(2)Ni and(Nb,Ti)ss *** aging treatment at 700℃for 6 and100 h,the distribution of Ti_(2)Ni and(Nb,Ti)ss precipitates increases in *** new type of precipitate is observed in the specimen aged at 700℃.After aging at800℃for 100 h,numerous nanosized Ni_(2)TiAl phases are precipitated within the *** and aging treatments improve the tensile properties at room *** strength and ductility are improved after solution treatment at 1100℃plus aging treatment at 800℃for 6 h or 700℃for 100 *** aging time prolonging to 100 h at 800℃,the precipitation of fine Ni2TiAl particles leads to the improvement in tensile strength and deterioration of elongation.

关键词： NiTi-Al-based alloy Intermetallics Microstructure Mechanical properties Heat treatment

Quasi-static and dynamic plastic deformation behavior in titanium with vanadium addition

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Rare Metals 2023年第7期42卷 2361-2370页

作者： Qiao-Chu Wang song-xiao Hui Wen-Jun Ye Rui Liu xiao-yun song State Key Laboratory for Fabrication&Processing of Nonferrous Metals General Research Institute for Nonferrous MetalsBeijing100088China

Compressive properties,microstructure features and deformation modes were investigated in binary Ti-(2,4,8)wt%V alloys during quasi-static(1×10^(-3)s^(-1))and dynamic(3×10^(3)s^(-1))*** compressive behavior shows a strong dependence on the loading strain rate and vanadium content contained in pure Ti,such that the flow stress increases with the increase in strain rate and vanadium content ranging from 2 wt%to 8 wt%.The microstructure features are clearly different from each other for alloys with different vanadium contents or under quasi-static and dynamic loading *** examination of deformation microstructures by optical microscopy and electron backscattered diffraction indicates that twinning behavior occurs during quasi-static and dynamic compressions and the twinning density increases with strain rate increasing but decreases with vanadium *** existence of{1012},{1121}and{1122}type twinning was further *** the help of the calculated Schmid factor map,the values of critical resolved shear stress of twinning types mentioned above have been obtained and verified to be rarely affected by the loading strain rate but sensitive to the vanadium *** vanadium-rich alloys(Ti-8V),twins are rarely observed but dislocation slip mechanism is active by transmission electron microscopy *** vanadium content increasing,both the critical resolved shear stress of twinning types and the content ofβphase with abundant slip systems increase,reflecting a suppression of twinning but an active dislocation slip mechanism.

关键词： Titanium alloys Strain rate Deformation mode Twinning Electron backscattered diffraction

Microstructure and tensile properties of isothermally forged Ni–43Ti–4Al–2Nb–2Hf alloy

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Rare Metals 2013年第5期32卷 475-479页

作者： xiao-yun song Yan Li Fei Zhang State Key Laboratory of Nonferrous Metals & Processes General Research Institute for Nonferrous Metals Key Laboratory of Aerospace Materials and Performance (Ministry of Education) Beijing University of Aeronautics and Astronautics

NiTi-Al-based alloys are promising high-tem- perature structural materials for aerospace and astronautics applications. A new NiTi-Al-based alloy Ni--43Ti-4AI- 2Nb-2Hf （at%） was processed via isothermal forging. The microstructure and mechanical properties at room temperature and high temperature were investigated through scanning electron microscope （SEM）, X-ray diffraction （XRD）, and tensile tests. Results show that the micro- structure of as-forged Ni-43Ti--4AI-2Nb-2Hf alloy con- sists of NiTi matrix, Ti2Ni phase, and Hf-rich phase. The simultaneous addition of Nb and Hf, which have strong affinities for Ti sites, promotes the precipitation of Hf-rich phases along the grain boundaries. The tensile strengths of Ni-43Ti-4A1-2Nb-2Hf alloy are dramatically increased compared with the ternary Ni-46Ti-4A1 alloy. At room temperature and 650℃, the yield stress of Ni--43Ti-4Al- 2Nb-2Hf alloy reaches 1,070 and 610 MPa, respectively, which are 30 % and 150 % higher than those of Ni--46Ti- 4Al alloy. The improved tensile property results from the solid solution strengthening by Nb and Hf, as well as the dispersion hardening of the Ti2Ni and Hf-rich phases.

关键词： Intermetallics NiTi-Al alloy Isothermal forging Tensile property Microstructure

Phase precipitation behavior and tensile property of a Ti-Al-Sn-Zr-Mo-Nb-W-Si titanium alloy

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Rare Metals 2018年第12期37卷 1064-1069页

作者： Wen-Jing Zhang xiao-yun song song-xiao Hui Wen-Jun Ye Wei-Qi Wang State Key Laboratory for Fabrication and Processing of Nonferrous Metals General Research Institute for Nonferrous Metals School of Materials and Metallurgy Northeastern University Baoti Group Co. Ltd.

The characteristic of precipitation behavior of a2 phase and silicide, and the tensile properties at room temperature and 650℃after heat treatments in anovel TiAl-Sn-Zr-Mo-Nb-W-Si titanium alloy（BTi-6431 S） were investigated by microstructure analysis and mechanics performance testing. The results show that no second phase precipitates after solution treatment(980 ℃/2 h, air cooling（AC）). However, when the solution-treated specimens are aged at 600 ℃（600 ℃/2 h,AC）,α;phase precipitates in the primary α phase, and the size of α;phase increases with the aging temperature increasing to 750 ℃. Meanwhile, 50-100-nm S2-type silicide particles precipitate along lamellar phase boundaries of transformed β phase after aging at 750 ℃. BTi-6431 S alloy shows the best650 ℃ ultimate tensile strength（UTS） and yield strength（YS） when treated in solution treatment. However, aging treatment results in a decline in 650 ℃ ultimate tensile strength. This may be attributed to the loss of solution strengthening due to the depletion of Al, Si and Zr of the matrix caused by the precipitation of Ti;Al and（TiZr）;Si;.Silicide is a brittle phase; therefore, its precipitation causes a sharp decrease in the room-temperature ductility of BTi-6431 S alloy.

关键词： High-temperature titanium alloy Precipitation behavior α_2 phase Silicide Tensile properties

α_(2) phase precipitation behavior and tensile properties at room temperature and 650℃ in an(α+β) titanium alloy

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Rare Metals 2021年第11期40卷 3261-3268页

作者： Wen-Jing Zhang xiao-yun song song-xiao Hui Wen-Jun Ye Yang Yu Yan-Feng Li State Key Laboratory of Nonferrous Metals and Processes GRIMAT Engineering Institute Co.Ltd.Beijing 100088China

The microstructure,room temperature and 650℃ tensile properties of an(α+β) titanium alloy were investigated after aging over a temperature range of 600-750℃ following solution *** results exhibit that both aging temperature and aging time influence the precipitation behavior of α_(2) phase,and the size ofα_(2) phase affects the tensile *** growth speed ofα_(2) phase gets quicker with the aging temperature increasing under the same aging *** a given aging temperature,the size of α_(2) phase gets larger when prolonging the aging *** are significant improvements in yield and ultimate tensile strength at room temperature and 650 ℃ after aging at 600℃ for 2 h,but these values decrease with the size of α_(2) phase *** is found that α_(2) phase,less than 7 nm,does not impair the roomtemperature ***,when the size of α_(2) phase grows up from 7 to 15 nm,ductility decreases *** 650 ℃ tensile process,with the particle size increasing from 3 to 15 nm,the interaction between moving dislocations and coherent particles changes from cutting mechanism to bypass mechanism.

关键词： Aging treatment α_(2)phase Tensile properties Interaction mechanism

Microstructure and tensile properties of Ti-62421S alloy plate with different annealing treatments

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Rare Metals 2018年第7期37卷 568-573页

作者： Yong-Ling Wang xiao-yun song Wen Ma Wen-Jing Zhang Wen-Jun Ye song-xiao Hui State Key Laboratory of Nonferrous Metals and Processes General Research Institute for Nonferrous Metals Division of Science and Technology Information General Research Institute for Nonferrous Metals

Ti-62421S （Ti-6A1-2Sn-4Zr-2Nb-lMo-0.2Si） is a novel short-time using high-temperature titanium alloy. The effects of annealing on microstructure and tensile properties of Ti-62421S alloy plate were studied through optical microscopy （OM）, electron probe microanalysis （EPMA）, transmission electron microscopy （TEM）, and tensile tests. The results show that, with annealing tem- perature increasing, the volume fraction of primary α（αp）- phase decreases while that of transformed β（βt）-structure and secondary α （αs）-phase increases. The room-temperature strength and plasticity are insensitive to annealing temperature. However, with annealing temperature increasing, the tensile strength decreases at 550℃, while increases at 600 and 650℃ instead. It is suggested that, at 550℃, the strengthening mechanism is mainly boundary strengthening and the biggest contributor is ap-phase by providing αp/β-boundary area. Above 600 ℃, the strengthening mechanism is grain strengthening, where αs-phase strengthens the β-phase.

关键词： High temperature titanium alloy Ti-62421S Heat treatment Microstructure Tensile properties

Dynamic stress–strain properties of Ti–Al–V titanium alloys with various element contents

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Rare Metals 2013年第6期32卷 555-559页

作者： Rui Liu song-xiao Hui Wen-Jun Ye Cheng-Lin Li Yan-Yan Fu Yang Yu xiao-yun song State Key Laboratory of Nonferrous Metals General Research Institute for Nonferrous Metals

A series of Ti–Al–V titanium alloy bars with nominal composition Ti–7Al–5V ELI,Ti–5Al–3V ELI,commercial Ti–6Al–4V ELI and commercial Ti–6Al–4V were *** alloys were then heat treated to obtain bimodal or equiaxed microstructures with various contents of primary a *** compression properties of the alloys above were studied by split Hopkinson pressure bar system at strain rates from 2,000 to 4,000 *** results show that Ti–6Al–4V alloy with equiaxed primary a(ap)volume fraction of 45 vol%or 67 vol%exhibits good dynamic properties with high dynamic strength and absorbed energy,as well as an acceptable dynamic ***,all the Ti53ELI specimens and Ti64ELI specimens with ap of 65 vol%were not fractured at a strain rate of4,000 *** appears that the undamaged specimens still have load-bearing *** strength of Ti–Al–V alloy can be improved as the contents of elements Al,V,Fe,and O increase,while dynamic strain is not sensitive to the composition in the appropriate *** effects of primary alpha volume fraction on the dynamic properties are dependent on the compositions of Ti–Al–V alloys.

关键词： Dynamic properties Alloying content Microstructure Titanium alloy

β-Arrestin-2 enhances endoplasmic reticulum stress-induced glomerular endothelial cell injury by activating transcription factor 6 in diabetic nephropathy

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World Journal of Diabetes 2024年第12期15卷 2322-2337页

作者： Jiang Liu xiao-yun song Xiu-Ting Li Mu Yang Fang Wang Ying Han Ying Jiang Yu-Xin Lei Miao Jiang Wen Zhang Dong-Qi Tang Center for Gene and Immunotherapy Institute of Medical SciencesThe Second HospitalCheeloo College of MedicineShandong UniversityJinan 250033Shandong ProvinceChina Center for Gene and Immunotherapy Cheeloo College of MedicineShandong UniversityJinan 250033Shandong ProvinceChina Medical Device and Pharmaceutical Packaging Inspection Shandong Institute of Medical Device and Pharmaceutical Packaging InspectionJinan 250101Shandong ProvinceChina Center of Animal Institute of Medical SciencesThe Second HospitalCheeloo College of MedicineShandong UniversityJinan 250033Shandong ProvinceChina Clinical Skill Training Centre The Second HospitalCheeloo College of MedicineShandong UniversityJinan 250033Shandong ProvinceChina

BACKGROUND Glomerular endothelial cell(GENC)injury is a characteristic of early-stage diabetic nephropathy(DN),and the investigation of potential therapeutic targets for preventing GENC injury is of clinical *** To investigate the role ofβ-arrestin-2 in GENCs under DN *** Eight-week-old C57BL/6J mice were intraperitoneally injected with streptozotocin to induce *** were transfected with plasmids containing siRNA-β-arrestin-2,shRNA-activating transcription factor 6(ATF6),pCDNA-β-arrestin-2,or ***,adeno-associated virus(AAV)containing shRNA-β-arrestin-2 was administered via a tail vein injection in DN *** The upregulation ofβ-arrestin-2 was observed in patients with DN as well as in GENCs from DN *** ofβ-arrestin-2 reduced apoptosis in high glucose-treated GENCs,which was reversed by the overexpression of ***,overexpression ofβ-arrestin-2 Led to the activation of endoplasmic reticulum(ER)stress and the apoptosis of GENCs which could be mitigated by silencing of ***,knockdown ofβ-arrestin-2 by the administration of AAV-shRNA-β-arrestin-2 alleviated renal injury in DN *** Knockdown ofβ-arrestin-2 prevents GENC apoptosis by inhibiting ATF6-mediated ER stress in vivo and in ***,β-arrestin-2 may represent a promising therapeutic target for the clinical management of patients with DN.

关键词： Diabetic nephropathy Glomerular endothelial cell β-Arrestin-2 Activating transcription factor 6 Endoplasmic reticulum stress

Electrochemical conversion of methane to bridge the gap in the artificial carbon cycle

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Journal of Energy Chemistry 2025年第1期100卷 286-308页

作者： Yuhao Peng Yuefeng song Ihar Razanau Juanxiu xiao Wei xiao Di Hu Guoxiong Wang College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power Sources Wuhan University State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Dalian Institute of Chemical Physics Chinese Academy of Sciences Laboratory of Physical-Chemical Technologies SSPA Scientific and Practical Materials Research Centre of NAS of Belarus State Key Laboratory of Marine Resources Utilization in South China Sea Collaborative Innovation Center of Marine Science and Technology School of Marine Science and Engineering Hainan University Department of Chemical and Environmental Engineering University of Nottingham Ningbo China

Methane, an abundant one-carbon（C1） resource, is extensively used in the industrial production of vital fuels and value-added chemicals. However, current industrial methane conversion technologies are energy-and carbon-intensive, mainly due to the high activation energy required to break the inert C–H bond, low selectivity, and problematic side reactions, including CO2emissions and coke deposition. Electrochemical conversion of methane（ECM） using intermittent renewable energy offers an attractive solution, due to its modular reactor design and operational flexibility across a broad spectrum of temperatures and pressures. This review emphasizes conversion pathways of methane in various reaction systems, highlighting the significance and advantages of ECM in facilitating a sustainable artificial carbon cycle. This work provides a comprehensive overview of conventional methane activation mechanisms and delineates the complete pathways of methane conversion in electrolysis contexts. Based on surface/interface chemistry, this work systematically analyzes proposed reaction pathways and corresponding strategies to enhance ECM efficiency towards various target products, including syngas, hydrocarbons, oxygenates, and advanced carbon materials. The discussion also encompasses opportunities and challenges for the ECM process, including insights into ECM pathways, rational electrocatalyst design, establishment of benchmarking protocols, electrolyte engineering, enhancement of CH4conversion rates, and minimization of CO2emission.

关键词： Activation energy

一种基于社交影响力和平均场理论的信息传播动力学模型

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物理学报 2017年第3期66卷 227-239页

作者：肖云鹏李松阳刘宴兵重庆邮电大学网络与信息安全技术重庆市工程实验室重庆400065

在线社会网络中,信息传播蕴含着复杂的动力学成因.本文将传染病模型与社交影响力要素相结合,并针对影响力度量中主要研究静态网络拓扑结构、忽略个体行为特征的问题,提出一种基于动态节点行为和用户影响力的信息传播动力学模型,旨在量... 详细信息

在线社会网络中,信息传播蕴含着复杂的动力学成因.本文将传染病模型与社交影响力要素相结合,并针对影响力度量中主要研究静态网络拓扑结构、忽略个体行为特征的问题,提出一种基于动态节点行为和用户影响力的信息传播动力学模型,旨在量化影响力强度,为研究信息扩散过程中不同用户群体状态转变提供理论依据.首先,在网络拓扑结构和用户行为两方面,提取个人记忆和用户交互两个表征,分析影响力形成的内因和外因两个动力学成因,并基于多元线性回归模型,提出一种度量用户社会影响力的方法.其次,在传统传染病SIR(susceptible-infected-recovered)模型基础上,结合信息扩散与传染病蔓延相似的传播机理,综合考虑信息传播的多源并发性和双向性,引入影响力因子,利用平均场理论改进得到一种基于用户影响力的信息传播模型.实验表明,该模型能有效地解释在线社会网络中信息传播的动力学原因,感知社会网络中信息传播演化态势.

关键词：信息传播传播动力学社交影响力平均场理论