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Twinning induced remarkable strain hardening in a novel Fe_(50)Mn_(20)Cr_(20)Ni_(10) medium entropy alloy

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Journal of Iron and Steel Research International 2021年第11期28卷 1463-1470页

作者： Ming-jie Qin Xi Jin Min Zhang Hui-jun Yang Jun-wei qiao College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024ShanxiChina State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

The microstructures and tension properties of Fe_(50)Mn_(20)Cr_(20)Ni_(10) medium entropy alloy(MEA)were investigated,which was produced by vacuum induction melting and subsequently was homogenized at 1200 C for 6 *** characterization shows the single-phase solid solution with face-centered cubic structure by means of transmission electron microscopy and scanning electron microscopy combined with energy disperse *** Fe-MEA has an ultimate tensile strength of 550±10 MPa and a high strain hardening exponent,n,of 0.41 as well as a higher ductility(60%)than those of CrMnFeCoNi *** single-phase solid solution deforms plastically via dislocations and *** boundaries associated with deformation twinning impede dislocation motion,enhancing the strain hardening *** article focuses on the insights into the concept of Fe-MEAs and provides a potential direction for the future development of high entropy alloys and MEAs.

关键词： Medium entropy alloy Alloy design Labusch model Twinning induced plasticity Strain hardening

基于自燃烧技术的铁铝酸钙固溶体低温制备与特性研究

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长江科学院院报 2024年第9期41卷 146-152,160页

作者：汪健雷金松方国宝乔鑫位李杨董芸严建军安徽省引江济淮集团有限公司合肥231200 安徽水安建设集团股份有限公司合肥231200 长江勘测设计集团有限公司武汉430010 安徽省水利水电勘测规划设计研究院合肥231200 长江科学院材料与结构研究所武汉430010

熟料煅烧是影响硅酸盐水泥生产能耗的关键环节,而熟料矿物相的高效能低温制备是水泥工业研究的重点。以可溶性的金属硝酸盐和尿素为原料,借助自蔓延燃烧(SPCR)法在低温下制备出铁铝酸四钙(C_(4)AF),并借助X射线衍射(XRD)、傅里叶变换红... 详细信息

熟料煅烧是影响硅酸盐水泥生产能耗的关键环节,而熟料矿物相的高效能低温制备是水泥工业研究的重点。以可溶性的金属硝酸盐和尿素为原料,借助自蔓延燃烧(SPCR)法在低温下制备出铁铝酸四钙(C_(4)AF),并借助X射线衍射(XRD)、傅里叶变换红外(FTIR)、扫描电子显微镜(SEM)和等温微量热技术,研究了合成C_(4)AF的矿物组成、结晶程度、颗粒形貌、水化特性等特性。结果表明:SPCR法能够在500℃恒温2 h制备出纯度和结晶程度均较好的C_(4)AF,优选的原材料质量比为mCa(NO_(3))_(2)·4H_(2)O∶mAl(NO_(3))_(3)·9H_(2)O∶mFe(NO_(3))_(3)·9H_(2)O∶mCO(NH_(2))_(2)=1.259∶1.0∶1.077∶2.664。CaCO_(3)是SPCR法制备C_(4)AF的过渡相,增加尿素用量有利于提高反应温度,改善C_(4)AF的结晶程度。合成C_(4)AF具有较高的水化活性,水化30 min内出现放热峰,水化过程中无休眠期出现,完全水化时的水化热为474 J/g。

关键词：硅酸盐水泥熟料铁铝酸四钙自蔓延燃烧低温

Deformation behavior and plastic instability of boronized Al0.25CoCrFeNi high-entropy alloys

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International Journal of Minerals,Metallurgy and Materials 2020年第10期27卷 1363-1370页

作者： Jin-xiong Hou Jing Fan Hui-jun Yang Zhong Wang Jun-wei qiao College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Interface Science and Engineering in Advanced Materials(Ministry of Education Taiyuan University of TechnologyTaiyuan 030024China

Using thermochemical treatments,boronized layers were successfully prepared on Al0.25CoCrFeNi high-entropy alloys(HEAs).The thickness of the boronized layers ranged widely from 20 to 50μm,depending on the heat treatment *** remarkably improved the surface hardness from HV 188 to HV 1265 after treating at 900°C for 9 ***,boronizing enhanced the yield strength of HEAs from 195 to 265 MPa but deteriorated the tensile *** crackings in the boride layers significantly decreased the *** insufficient work-hardening capacity essentially facilitated the plastic instability of the boronized *** decreasing substrate thickness,the fracture modes gradually transformed from dimples to quasi-cleavage and eventually to cleavage.

关键词： boronizing high-entropy alloys boride layers tensile strength cleavage fracture

FCC-to-HCP Phase Transformation in CoCrNi_x Medium-Entropy Alloys

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Acta Metallurgica Sinica(English Letters) 2020年第8期33卷 1151-1158页

作者： Jia-Qi Zhao Hua Tian Zhong Wang Xue-Jiao Wang Jun-wei qiao College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China College of Information and Computer Taiyuan University of TechnologyTaiyuan 030024China

A hybrid first-principles/Monte Carlo simulation is combined with experiments to study the structure and elastic properties of CoCrNi_x(x=1-0.5)*** experimental X-ray diffraction patterns show that the structures have changed from the single-phase face-centered cubic(FCC)structure at x=1-0.8 to the coexistence of FCC and the hexagonal close-packed structures at x=0.7-0.5,which is further confirmed by calculations on mixing *** elastic moduli by calculation are basically in agreement with ***-temperature tension shows that the six alloys have a certain plasticity,the strength and plasticity of the alloys have a linear decrease with the decrease in Ni contents,and the plasticity of the alloys drops from 84 to 23%.Furthermore,first-principles density function theory calculations were employed to reveal the electronic and magnetic structures of *** electron density of states for all alloys is asymmetrical,which illustrates that the alloys are *** is found that Cr atoms can suppress the ferromagnetism of alloys,since Cr atoms have both positive and negative magnetic moments in all alloys.

关键词： Hexagonal close-packed(HCP)structure Medium-entropy alloys Magnetic Mechanical properties Phase transformation High-entropy alloys

Robust estimation for the fractional integral and derivative of the output for a class of fractional order linear systems

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Robust estimation for the fractional integral and derivative...

岩心力学实验刻度弹性参数的页岩脆性评价方法改进

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作者： Yan-qiao wei Xing wei Da-Yan Liu Driss Boutat INSA Centre Val de Loire Universite d’Orleans

ISBN: (纸本)9781538629185

This paper aims at non-asymptotically estimating the fractional integral and derivative of the output for a class of fractional order linear systems in noisy environment with unknown initial *** this purpose,the considered system modeled by the pseudo-state space representation is firstly transformed into a fractional order differential ***,based on the obtained equation the modulating functions method is applied to obtain algebraic integral formulae for the desired fractional integral and derivative,where the undesired initial conditions are *** integral formulae can give robust estimations in discrete noisy ***,it is shown how to construct the used modulating ***,numerical simulations are provided to demonstrate the efficiency of the proposed method.

关键词： Fractional integral and derivative estimator pseudo-state space representation non-asymptotic estimation modulating functions method

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西安石油大学学报（自然科学版） 2024年第5期39卷 35-42页

作者：王团赵海波郑建东乔卫唐晓花田得光大庆油田有限责任公司勘探开发研究院黑龙江大庆163712 东北石油大学地球科学学院黑龙江大庆163318 黑龙江省致密油和泥岩油成藏研究重点实验室黑龙江大庆163712

页岩储层的规模动用关键在于水力压裂造缝,复杂缝网形成的地质因素取决于天然裂缝、水平应力差及脆性,高脆性是压裂形成缝网的必要条件之一。针对现有弹性参数脆性指数评价方法中杨氏模量和泊松比权重系数占比不清的问题,在岩心三轴力... 详细信息

页岩储层的规模动用关键在于水力压裂造缝,复杂缝网形成的地质因素取决于天然裂缝、水平应力差及脆性,高脆性是压裂形成缝网的必要条件之一。针对现有弹性参数脆性指数评价方法中杨氏模量和泊松比权重系数占比不清的问题,在岩心三轴力学测试和全岩样品分析的基础上,提出基于应力-应变曲线的脆性评价指标,通过统计交会分析,明确杨氏模量和泊松比对岩石脆性敏感程度,并且根据脆性评价指标和杨氏模量及泊松比的相关系数,采用等比例方式进一步刻度杨氏模量和泊松比的权重系数,改进了现有的弹性参数脆性指数评价方法。东部盆地页岩层系应用实例表明,岩心力学实验刻度后的弹性参数脆性评价方法更加合理有效,能更好地反映页岩储层脆性分布特征。

关键词：页岩脆性评价力学测试弹性参数杨氏模量泊松比

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丛枝菌根真菌提高植物干旱胁迫抗性的研究现状

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中国甜菜糖业 2024年第2期 39-42页

作者：乔巍郭娜王颖张威魏丽娜张煜吕晓红接伟光黑龙江东方学院食品工程学院黑龙江哈尔滨150066 江苏食品药品职业技术学院药学院江苏淮安223023 黑龙江省林业科学研究所黑龙江哈尔滨150081 黑龙江大学生命科学学院农业微生物技术教育部工程研究中心黑龙江省寒区植物基因与生物发酵重点实验室黑龙江省普通高校微生物重点实验室哈尔滨150080

我国是世界上受干旱影响较严重的国家之一,干旱胁迫严重影响着植物尤其是粮食作物的生长,严重制约着粮食产量。尽管植物通过进化或者人工干预,在一定程度上可以自我调节以承受环境因素带来的影响,但其成本和应用领域限制了其大规模推广... 详细信息

我国是世界上受干旱影响较严重的国家之一,干旱胁迫严重影响着植物尤其是粮食作物的生长,严重制约着粮食产量。尽管植物通过进化或者人工干预,在一定程度上可以自我调节以承受环境因素带来的影响,但其成本和应用领域限制了其大规模推广与应用。探索利用微生物缓解干旱胁迫作用,提高粮食作物的产量具有十分重要的经济效益和社会效益。研究者对丛枝菌根真菌与植物根系的共生过程、干旱对植物的不利影响、丛枝菌根真菌提高植物抗旱作用机制及影响因素进行了综述,并对目前丛枝菌根真菌的抗旱研究中存在的问题及发展前景进行了展望。

关键词：丛枝菌根真菌干旱胁迫抗性共生过程作用机制

武汉市森林防灭火应急资源“一张图”建设与应用

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城市勘测 2024年第4期 31-33页

作者：喻静敏乔炜江威季婷婷刘福韩念龙武汉市测绘研究院湖北武汉430022 武汉市市政路桥有限公司湖北武汉430015 武汉市政环境工程建设有限公司湖北武汉430015

基于实战经验,探讨了的森林防灭火应急资源一张图服务平台的建设思路,实现了森林防灭火多源时空数据的汇聚融合、地图资源的高效可视化渲染和防灭火应急资源优化调度,并在武汉市森林防灭火应急管理工作中验证了平台的有效性和实用性,为... 详细信息

基于实战经验,探讨了的森林防灭火应急资源一张图服务平台的建设思路,实现了森林防灭火多源时空数据的汇聚融合、地图资源的高效可视化渲染和防灭火应急资源优化调度,并在武汉市森林防灭火应急管理工作中验证了平台的有效性和实用性,为提升应急管理信息化水平提供了参考。

关键词：应急管理森林防灭火多源时空数据一张图

A New Hemiterpene Derivative from Prinsepia utilis

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Chinese Chemical Letters 2006年第2期17卷 198-200页

作者： Jun Yi HU wei qiao Yoshihisa TAKAISHI Hong Quart DUAN The College of Pharmaceuticals and Biotechnology Tianjin University Tianjin 300072 School of Chemical Engineering Anshan university of Science ＆ Technology Anshan 114002 The School of Pharmacy Tianjin Medical University Tianjin 300070 Faculty of Pharmaceutical Sciences University of Tokushima Shomachi 1-78 Tokushima 770-8505 Japan

A new hemiterpenoid, （＋）-（2R,3S）-2-chloro-3-hydroxy-3-methyl-T-buty-rolactone was isolatexi from the leaves of Prinsepia utilis Royle. Its structure was clucidatexi by spectroscopic methods and X-ray crystallogra... 详细信息

关键词： Prinsepia utilis hemitcrpcne (+)-(2R 3S)-2-chloro-3-hydroxy-3-methyl-T-butyrolac-tone.