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Analysis of local crystallographic orientation in an annealed Ti60 billet

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journal of Materials Science & Technology 2019年第4期35卷 591-595页

作者： z.B.zhao z.Liu Q.j.Wang j.R.Liu R.Yang Institute of Metal Research Chinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China

A heterogeneous microstructure in terms of local orientation distribution is often found in near-α titanium alloys. The presence of large regions with similar crystallographic orientation, called ‘macrozones',could drastically decrease the fatigue performance of titanium alloys. The present work reports on the crystallographic orientation of a near-α titanium alloy, Ti60, billet after annealing in an α+β phase *** texture was found to be weak, and no obvious macrozone was found in our measured zone where the variant selection is suppressed. Meanwhile, in-depth electron backscattered diffraction(EBSD) analysis was applied to evaluate the final microstructure, and the mechanisms by which they formed were analyzed.

关键词： Titanium alloys Microstructure Texture Heat treatment EBSD

MICROSTRUCTURE AND MECHANICAL PROPERTIES OFP/M TiAl ALLOYS AND THE TEMPERATURE EFFECT

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Acta Metallurgica Sinica(English Letters) 1998年第6期11卷 417-424页

作者： z.M.sun H.Hashimoto S.Sumi Y.H.Park T.Abe z.H.Shan Tohoku Natl Industrial Research Inst Sendai Japan

Two intermetallic compounds of Ti-50at.%Al and Ti-48at.%Al-2at.%Cr were prepared with a mechanical alloying and pulse discharge sintering process. The as-sintered material shows a microstructure of equiaxed gamma grain with sub-micron size. Heat treatments in Vacuum at different temperatures up to 1573 K were conducted on the sintered materials. The microstructure of the material coarsened considerably after heat treatment at temperatures higher than 1523 K. The mechanical properties of the as-sintered and the heat treated materials were measured at temperatures up to 973 K, with four-point bending tests. Experimental results indicate that the addition of Cr increases the fracture strength of the intermetallic compound at room temperature and at elevated temperatures as well. The bending fracture strength increases with increasing testing temperature up to about 873 K and a decrease following up. Both fracture strength and fracture strain of the material were found to be improved by heat treatment. (Edited author abstract) 10 Refs.

关键词： titanium aluminide mechanical alloying heat treatment mechanical property temperature

Novel method for random vibration analysis of single-degree-of-freedom vibroimpact systems with bilateral barriers

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Applied Mathematics and Mechanics(English Edition) 2019年第12期40卷 1759-1776页

作者： Lincong CHEN Haisheng zHU j.Q.sun College of Civil Engineering Huaqiao UniversityXiamen 361021Fujian ProvinceChina School of Engineering University of CaliforniaMercedCA 95343U.S.A

The vibroimpact systems with bilateral barriers are often encountered in ***,the dynamics of the vibroimpact system with bilateral barriers is full of *** closed-form solutions were *** this paper,we propose a novel method for random vibration analysis of single-degree-of-freedom(SDOF)vibroim-pact systems with bilateral barriers under Gaussian white noise excitations.A periodic approximate transformation is employed to convert the equations of the motion to a con-tinuous *** probabilistic description of the system is subsequently defined through the corresponding Fokker-Planck-Kolmogorov(FPK)*** closed-form station-ary probability density function(PDF)of the response is obtained by solving the reduced FPK equation and using the proposed iterative method of weighted residue together with the concepts of the circulatory probability flow and the potential probability ***,the versatility of the proposed approach is demonstrated by its application to two typical *** that the solution obtained by using the proposed method can be used as the benchmark to examine the accuracy of approximate solutions obtained by other methods.

关键词： bilateral barrier vibroimpact system weighted residue method iterative random vibration

Designing metallic glasses with optimal combinations of glass-forming ability and mechanical properties

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journal of Materials Science & Technology 2021年第8期67卷 254-264页

作者： S.j.Wu z.Q.Liu R.T.Qu z.F.zhang Laboratory of Fatigue and Fracture for Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China

It is a long-standing challenge to search for metallic glasses(MGs)with optimal combinations of glassforming ability(GFA),strength and toughness in the vast compositional *** taking into account both recently developed ellipse criterion and temperature-based GFA criterion,here we established quantitative correlations among compositions,elastic constants,GFA and mechanical properties of MGs,which enable to predict the GFA,fracture strength and fracture surface simultaneously in advance once the compositions of MGs are *** data confirm the validity of this approach in ***,a strategy for designing MGs with optimal combinations of strength,toughness and GFA is proposed,which allows for high-throughput discovering glass formers with excellent mechanical properties.

关键词： Metallic glass Composition Elastic constant Mechanical property Glass-forming ability

Development and application of functional gene arrays for microbial community analysis

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中国有色金属学会会刊：英文版 2008年第6期18卷 1319-1327页

作者： z. L. HE j. D. VAN NOSTRAND L.Y. WU j. z. zHOU Institute for Environmental Genomics Department of Botany and Microbiology University of Oklahoma Norman OK 73019 USA

功能的基因标记能关于功能的基因差异和微生物引起的社区的潜在的活动提供重要信息。尽管 microarray 技术成功地被使用了为纯文化学习基因表示，简单、人工的微生物引起的社区，改编如此的一种技术分析复杂微生物引起的社区仍然以设计... 详细信息

功能的基因标记能关于功能的基因差异和微生物引起的社区的潜在的活动提供重要信息。尽管 microarray 技术成功地被使用了为纯文化学习基因表示，简单、人工的微生物引起的社区，改编如此的一种技术分析复杂微生物引起的社区仍然以设计，样品准备，和数据分析提出很多挑战。这个工作集中于功能的基因数组(FGA ) 的开发和应用程序为微生物引起的社区研究指向关键功能的基因标记。一些与 FGA 有关明确地给问题调音，例如 oligonucleotide 探查设计， nucleic 酸抽取和纯化，数据分析，特性，敏感，和量的能力详细被讨论。最近的研究证明了 FGA 能从许多自然环境关于微生物引起的社区提供特定、敏感、潜在地量的信息并且控制生态系统。这种技术被期望革命化微生物引起的社区的分析，并且连接微生物引起的结构到生态系统工作。

关键词：微数列应用函数基因标记微生物种群

2022年泸定6.8级地震房屋震害及其统计分析

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地震研究 2025年第1期48卷 123-131页

作者：孙路刘金龙湖州职业技术学院建筑工程学院浙江湖州313000 湖州市绿色建筑技术重点实验室浙江湖州313000 中国地震局工程力学研究所中国地震局地震工程与工程振动重点实验室黑龙江哈尔滨150080

2022年四川省甘孜州泸定县发生6.8级地震。依据现场调查资料,介绍了震区房屋的主要结构类型及其建造特点,总结了各类房屋结构的典型震害现象,探讨了各类房屋典型震害特征的产生机理。通过震害数据的统计分析,建立了本次地震中各类结构... 详细信息

2022年四川省甘孜州泸定县发生6.8级地震。依据现场调查资料,介绍了震区房屋的主要结构类型及其建造特点,总结了各类房屋结构的典型震害现象,探讨了各类房屋典型震害特征的产生机理。通过震害数据的统计分析,建立了本次地震中各类结构房屋的震害矩阵,并与其他学者的研究成果进行了对比,研究了不同房屋类型各地震破坏等级分布规律,给出了砖混结构房屋的地震易损性曲线。根据本次地震的震害特点,给出了提升房屋抗震能力的建议。

关键词：泸定6.8级地震房屋震害抗震能力

Non-monotonic temperature evolution of nonlocal structure–dynamics correlation in Cuzr glass-forming liquids

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Chinese Physics B 2021年第7期30卷 370-375页

作者： W j jiang M z Li Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials&Micro-nano Devices Renmin University of ChinaBeijing 100872China

The structure–dynamics correlations in a nonlocal manner were investigated in Cuzr metallic glass-forming liquids via classical molecular dynamics simulations.A spatial coarse-graining approach was employed to incorporate the nonlocal structural information of given structural order parameters in the structure–dynamics *** is found that the correlation between structure order parameters and dynamics increases with increasing coarse-graining length and has a characteristic length ***,the characteristic correlation length exhibits a non-monotonic temperature evolution as temperature approaches glass transition temperature,which is not sensitive to the considered structure order *** results unveil a striking change in the structure–dynamics correlation,which involves no fitting theoretical *** findings provide new insight into the structure–dynamics correlation in glass transition.

关键词： metallic glass-forming liquid structure–dynamics correlation molecular dynamics simulation

EVOLUTION OF AS-CAST MICROSTRUCTURES OF 356 ALUMINIUM ALLOY CAST BY LIQUIDUS CASTING

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Acta Metallurgica Sinica(English Letters) 2003年第1期16卷 60-64页

作者： j.Dong G.M.Lu j.z.Cui z.H.zhao Lab. of Electromagnttic Proc. of Mat Northeastern Univ. Shenyang 110004 China

A new method (liquidus casting) was used for 356 Al alloy semi-solid slurry making. The structures of 356 Al alloy cast by a Fe mould and semi-continuous casting machine at different temperatures were investigated. How the globular grains form was also discussed. The results show that either being cast by single Fe mould or semi-continuous machine, the micro structures are not conventional dendrites but fine and net-globular grains. The average gram size is smaller than 30μm and suitable enough for thixoforming, meanwhile it can improve the mechanical properties of following products. Under the suitable casting velocity and cooling intensity, most of global grains prolong their global growth and collide with each other before dendritic growth because of the large amount of the nucleation sites.

关键词： liqwdus casting microstructure 356 Al alloy

数字经济发展对FDI流入的影响分析--基于省级面板数据

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黄冈师范学院学报 2025年第1期45卷 103-108,126页

作者：孙茜武汉学院金融与经济学院湖北武汉430212 中南财经政法大学工商管理学院湖北武汉430073

基于2010—2020年中国省级面板数据,通过主成分分析法测算出各省份数字经济发展水平,并检验了数字经济发展对FDI流入的影响及作用机制。结果表明:数字经济发展能显著促进FDI流入,这一结果通过了内生性检验和多种稳健性检验。数字经济促... 详细信息

基于2010—2020年中国省级面板数据,通过主成分分析法测算出各省份数字经济发展水平,并检验了数字经济发展对FDI流入的影响及作用机制。结果表明:数字经济发展能显著促进FDI流入,这一结果通过了内生性检验和多种稳健性检验。数字经济促进FDI流入具有区位和时间的差异性。在东部和西部地区,数字经济的发展能显著促进FDI流入,而这种促进效果在中部地区不显著。2014年以前,数字经济的发展对FDI流入的促进作用不明显,2014年以后促进作用才显现。数字经济主要通过提高人力资本和降低交易成本两个渠道影响FDI流入。

关键词：数字经济 FDI 人力资本交易成本