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Inhibition of galvanic corrosion in Al/Cu coupling model by synergistic combination of 3-Amino-1,2,4-triazole-5-thiol and cerium chloride

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journal of Materials Science & Technology 2020年第9期44卷 102-115页

作者： Inime ime Udoh Hongwei Shi Mohammad Soleymanibrojeni Fuchun Liu En-Hou Han CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China University of Chinese Academy of Sciences Beijing100049China University of Science and Technology of China Hefei230026China

Asynergistic inhibition study was carried out on an aluminium/copper galvanic coupling model in neutral aerated NaCl solution using scanning vibrating electrode technique(SVET).The approach allows the simulation of the local micro-galvanic cells of AA2024-T3 obtained from the potential difference between the intermetallic particles(IMPs)and the aluminium *** inhibition effect of CeCl3 and 3-Amino-1,2,4-triazole-5-thiol(ATAT)was demonstrated by the reduction in the galvanic current density over Al and Cu *** improved inhibition from positive synergistic effect was revealed by the combination of the two inhibitors after 24 h of immersion,with the best inhibition recorded for *** electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS)and time of flight secondary ion mass spectrometry(ToF-SIMS)were used to characterize the Ce-and ATAT-based complex film formed and to illustrate the mechanism of inhibition.

关键词： Aluminium alloy Galvanic corrosion Neutral inhibition Scanning vibrating electrode technique (SVET) X-ray photoelectron spectroscopy(XPS) Time of flight secondary ion mass spectrometry(ToF-SIMS)

Conditional coherent risk measures and regime-switching conic pricing

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Probability, Uncertainty and Quantitative Risk 2021年第4期6卷 267-300页

作者： Engel john C Dela vega Robert j Elliott UniSA Business University of South AustraliaSA 5000 AdelaideAustralia Haskayne School of Business University of CalgaryCalgaryAlbertaT2N 1N4Canada

This paper introduces and represents conditional coherent risk measures as essential suprema of conditional expectations over a convex set of probability measures and as distorted expectations given a concave distortion function.A model is then developed for the bid and ask prices of a European-type asset by a conic *** price process is governed by a modified geometric Brownian motion whose drift and diffusion coefficients depend on a Markov *** bid and ask prices of a European-type asset are then characterized using conic quantization.

关键词： Conditional coherent risk measures Markov chains Regime-switching Conic finance European options Distortion functions Conic quantization

21-Component compositionally complex ceramics: Discovery of ultrahigh-entropy weberite and fergusonite phases and a pyrochlore–weberite transition

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journal of Advanced Ceramics 2022年第4期11卷 641-655页

作者： Mingde QIN Heidy vega Dawei zHANG Sarath ADAPA Andrew j.WRIGHT Renkun CHEN jian LUO Department of Nano Engineering University of California San DiegoLa Jolla 92093USA Department of Chemistry and Biochemistry University of California San DiegoLa Jolla 92093USA Program of Materials Science and Engineering University of California San DiegoLa Jolla 92093USA Department of Mechanical and Aerospace Engineering University of California San DiegoLa Jolla 92093USA

Two new high-entropy ceramics(HECs)in the weberite and fergusonite structures,along with the unexpected formation of ordered pyrochlore phases with ultrahigh-entropy compositions and an abrupt pyrochlore–weberite transition,are discovered in a 21-component oxide *** the Gibbs phase rule allows 21 equilibrium phases,9 out of the 13 compositions examined possess single HEC phases(with ultrahigh ideal configurational entropies:~2.7kB per cation or higher on one sublattice in most cases).Notably,(15RE_(1/15))(Nb_(1/2)Ta_(1/2))O_(4) possess a single monoclinic fergusonite(C2/c)phase,and(15RE_(1/15))_(3)(Nb_(1/2)Ta_(1/2))_(1)O_(7) form a single orthorhombic(C222_(1))weberite phase,where 15RE_(1/15) represents Sc_(1/15)Y_(1/15)La_(1/15)Pr_(1/15)Nd_(1/15)Sm_(1/15)Eu_(1/15)Gd_(1/15)Tb_(1/15)Dy_(1/15)Ho_(1/15)Er_(1/15)Tm_(1/15) Yb_(1/15)Lu_(1/15).Moreover,a series of eight(15RE_(1/15))_(2+x)(Ti_(1/4)zr_(1/4)Ce_(1/4)Hf_(1/4))_(2−2x)(Nb_(1/2)Ta_(1/2))_(x)O_(7) specimens all exhibit single phases,where a pyrochlore–weberite transition occurs within 0.75

关键词： compositionally complex ceramics high-entropy ceramics(HECs) weberite pyrochlore fergusonite ultrahigh-entropy ceramics many-component ceramics

Structural Damage Detection Using a Modified Artificial Bee Colony Algorithm

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Computer Modeling in Engineering & Sciences 2016年第4期111卷 335-355页

作者： H.j.Xu z.H.Ding z.R.Lu j.K.Liu Department of Mechanics Sun Yat-sen UniversityGuangzhou 510006China

An optimization approach based on Artificial Bee Colony(ABC)algorithm is proposed for structural local damage detection in this *** objective function for the damage identification problem is established by structural parameters and modal assurance criteria(MAC).The ABC algorithm is presented to solve the certain objective *** the Tournament Selection Strategy and chaotic search mechanism is adopted to enhance global search ability of the certain algorithm.A coupled double-beam system is studied as numerical example to illustrate the correctness and efficiency of the propose *** simulation results show that the modified ABC algorithm can identify the local damage of the structural system efficiently even under measurement noise,which demonstrates the proposed algorithm has a higher damage diagnosis precision.

关键词： structural damage detection Artificial Bee Colony algorithm Modal Assurance Criteria coupled double-beam system Tournament Selection Strategy

Design and optimization of the composition and mechanical properties for non-equiatomic CoCrNi medium-entropy alloys

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journal of Materials Science & Technology 2023年第8期139卷 232-244页

作者： j.X.Yan z.j.zhang P.zhang j.H.Liu H.Yu Q.M.Hu j.B.Yang z.F.zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering Chongqing Jiaotong UniversityChongqing 400074China chool of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China School of Information Science and Engineering Shenyang University of TechnologyShenyang 111003China

The development of multi-principal element alloys(MPEAs,also called as high-or medium-entropy al-loys,HEAs/MEAs)provides tremendous possibilities for materials ***,designing MPEAs with desirable mechanical properties confronts great challenges due to their vast composition *** this work,we provide an essential criterion to efficiently screen the CoCrNi MEAs with outstanding strength-ductility *** negative Gibbs free energy difference△E_(FCC-BCC)between the face-centered cubic(FCC)and body-centered cubic(BCC)phases,the enhancement of shear modulus G and the decline of stacking fault energy(SFE)γ_(isf)are combined as three requisites to improve the FCC phase stability,yield strength,deformation mechanisms,work-hardening ability and ductility in the *** effects of chemical composition on△E_(FCC-BCC),G andγisf were investigated with the first principles calculations for Co_(x)Cr_(33)Ni_(67-x),Co_(33)Cr_(y)Ni_(67-y)and Co_(z)Cr_(66-z)Ni_(34)(0≤x,y≤67 and 0≤z≤66)*** on the essential criterion and the calculation results,the composition space that displays the neg-ative Gibbs free energy difference△E_(FCC-BCC),highest shear modulus G and lowest SFEγ_(isf)was screened with the target on the combination of high strength and excellent *** this context,the optimal composition space of Co-Cr-Ni alloys was predicted as 60 at.%-67 at.%Co,30 at.%-35 at.%Cr and 0 at.%-6 at.%Ni,which coincides well with the previous experimental evidence for Co_(55)Cr_(40)Ni_(5)*** valid-ity of essential criterion is further proved after systematic comparison with numerous experimental data,which demonstrates that the essential criterion can provide significant guidance for the quick exploitation of strong and ductile MEAs and promote the development and application of MPEAs.

关键词： Medium-entropy alloys First-principles calculations Phase stability Stacking-fault energy Strength Ductility

Shape Memory Effect,Thermal Expansion and Damping Property of Friction Stir Processed NiTip/Al Composite

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journal of Materials Science & Technology 2016年第2期32卷 162-166页

作者： D.R.Ni j.j.Wang z.Y.Ma Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang I10016China College of Material Science and Engineering ShenyangAerospace University Shenyang 110136China

NiTi particles reinforced aluminum （NiTip/Al） composite was prepared via friction stir processing, elimi- nating interfacial reaction and/or elemental diffusion. The NiTip in the composite maintained the intrinsic characteristic of a reversible thermoelastic phase transformation even after heat-treatment. The shape memory characteristic of the NiTip decreased the coefficient of thermal expansion of the Al matrix, and an apparent two-way shape memory effect was observed in the composite. The composite owned a good combination of adjustable damping and thermal physical properties.

关键词： Metal matrix composite Shape memory alloy Interface Differential scanning calorimetry (DSC)Damping

Distinct dendritic α phase emerging on the surface of primary α phase in a compressed near-α titanium alloy

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journal of Materials Science & Technology 2018年第4期34卷 666-669页

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

The characteristic of the surface morphology of primary α phase was studied in a deformed near-α tita- nium alloy. Dendritic α phase emerged on the surfaces of primary α phase when the alloy was air-cooled in α ＋β phase field after deformation. The dendritic α grain has the same orientation with its original primary α grain. The formation of the dendritic α phase could be explained by interface instability in epi- taxial growth process of the primary α phase. The dislocations induced by deformation could facilitate the formation of dendritic α phase leading to the dendritic α phase and more obvious with the increase of strain. The growth of dendritic α phase was finally limited by the nucleation of second α phase with cooling.

关键词： Epitaxial growth Dendritic α phase Microstructure Interface instability Hot deformation

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

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