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THE REINFORCING MECHANISM OF TiB2 IN TiB2/A357 COMPOSITE

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Acta Metallurgica Sinica(English Letters) 2003年第5期16卷 375-378页

作者： B.yu Y.J.z.ang z.X.zhao~ F.X.zhao: Q.K.Cai C.S.Liu ShenyangResearchInstituteofFoundry TheChineseAcademyofMachinerySciencesShenyang110022China EastChinaUniversityofScienceandTechnology Shanghai200237China SchoolofMaterials&Metallurgy NortheasternUniversityShenyang110004China

Mechanical properties were tested for in situ TiB2/A357 composite fabricated by LSM (mixed salts reaction) method. Micro structures of as cast and plastic deformed TiB2/A357 were investigated. The results show that there is a low misfit between (200) Al and (101)TiB2 with [011]//Al [101]TiB2. There is a change from fully dendritic structure of the α-Al of A357 to a rosette-type structure of TiB2/A357. Significant increases in proof stress and Young's modulus can be obtained at low TiB2 additions. There exist dislocation loops around neighboring TiB2 particles with about 0.1μm in diameter and dislocation multiplication near TiB2 particles.

关键词： TiB2/Al in situ composite reinforcing mechanism

Continuous preparation of composition-controllable Y-Ni alloy in LiF-YF_(3)-Y_(2)O_(3)molten salt

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Journal of Rare Earths 2023年第4期41卷 632-638页

作者： Bing yu Qicao Yan State Key Laboratoryof Baiyunobo Rare Earth Resource Researchesand Comprehensive Utilization Baotou Research Insttuteof RareEarthsBaotou 014030China Ganjiang Innovation Academy.Chinese Academy of Sciences Ganzhou 341000China

The Y-Ni alloy is a primary precursor for the preparation of high-performance La-Y-Ni-based hydrogen storage ***,it cannot be produced continuously at low cost,which limits the wide popularization and application of La-Y-Ni-based *** this paper,this problem was solved perfectly using electrochemical reduction of Y_(2)O_(3)in the LiF-YF_(3)*** is found that the reversible reduction from Y^(3+)to Y on the W electrode takes only one step,namely a significant soluble-soluble reaction controlled by Y^(3+)diffusion throughout the *** typical signals of square wave voltammetry(SWV)corresponding to different kinds of Y-Ni intermetallic compounds are observed in LiF-YF_(3)and LiF-YF_(3)-Y_(2)O_(3)melts,and reduction potential can become positive with the addition of Y_(2)O_(3),probably because of the formation of more complexes in the *** Y-Ni alloy samples were produced continuously and prepared via galvanostatic electrolysis by using bargain-price raw material(Y_(2)O_(3))and setting the current density at 10 A/cm^(2)on the nickel electrode,before they were collected into a bottom receiver.A series of analyses including scanning electron microscopy-energy idspersive X-ray spectroscopy(SEM-EDS),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),and inductively coupled plasma mass spectrometry(ICP-MS),demonstrate that concentration of yttrium in Y-Ni alloy is adjustable within the wide range of 44 wt%to 72 wt%by fine-tuning the electrolysis temperature(875-1060℃)in the LiF-YF_(3)system to ensure the optimal hydrogen storage performance and economic efficiency of La-Y-Ni-based hydrogen-storage materials.

关键词： Y^(3+) LiF-YF_(3)-Y_(2)O_(3) Electroreduction Chronopotentiometry Y-Ni alloy Rare earths

Certificateless network coding proxy signatures from lattice

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Frontiers of Computer Science 2023年第5期17卷 145-152页

作者： Huifang yu Ning Wang School of Cyberspace Security Xi’an University of Posts&TelecommunicationsXi’an 710121China

Network coding can improve the information transmission efficiency and reduces the network resource consumption,so it is a very good platform for information *** proxy signatures are widely applied in information security ***,certificateless proxy signatures based on classical number theory are not suitable for the network coding environment and cannot resist the quantum computing *** view of this,we construct certificateless network coding proxy signatures from lattice(LCL-NCPS).LCL-NCPS is new multi-source signature scheme which has the characteristics of anti-quantum,antipollution and *** LCL-NCPS,each source node user can output a message vector to intermediate node and sink node,and the message vectors from different source nodes will be linearly combined to achieve the aim of improving the network transmission rate and network *** terms of efficiency analysis of space dimension,LCL-NCPS can obtain the lower computation complexity by reducing the dimension of proxy *** terms of efficiency analysis of time dimension,LCL-NCPS has higher computation efficiency in signature and verification.

关键词： lattice multi-source signature scheme proxy signature post-quantum

Tensile Elastic Behavior of a zr-Cu-Ag-Al Bulk Metallic Glass

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Journal of Materials Science & Technology 2014年第6期30卷 595-598页

作者： Q.P.Cao J.B.Jin Q.yu X.D.Wang D.X.z.ang Y.Jiang J.z.Jiang International Center for New-Structured Materials (ICNSM) State Key Laboratory of Silicon MaterialsDepartment of Materials Science and Engineering Zhejiang University Department of Mechanical Engineering University of Nevada Reno NV 89557 USA State Key Laboratory of Modern Optical Instrumentation Zhejiang University

Tensile elastic behavior of bulk zr46（Cu4.5/5.5Ag1/5.5）46Al8 metallic glass was experimentally investigated. It exhibited linear and non-linear time-independent elastic deformation with a demarcative stress of approximately 500 MPa within the timescale in the present work, and repeated loading-unloading before yielding did not alter stress-strain relationship. The pure linear elastic strain limit is 0.6%, significantly lower than 2% as generally reported, but still much higher than 0.1% observed for typical crystalline alloys. Deviation from linear elastic behavior at stresses higher than 500 MPa is explained here as a macroscopic manifestation of local fluctuations in elastic strain, which becomes pronounced at stresses higher than the critical value. The occurrence of non-linear elasticity is possibly also related to the sinusoidal relationship between shear stress and atomic displacement.

关键词： Bulk metallic glass Tension test Elastic-plastic deformation

On free z_p-torus actions in dimensions two and three

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Science China Mathematics 2019年第2期62卷 391-410页

作者： Li yu Department of Mathematics Nanjing University

We confirm the Halperin-Carlsson conjecture for free z_p-torus actions(p is a prime) on 2-dimensional finite CW-complexes and free z_2-torus actions on closed 3-manifolds.

关键词： group homology Halperin-Carlsson conjecture z_p-torus free group action 3-manifold

Synthesis, Crystal Structure and Kinetic Mechanism of Thermal Decomposition of a zinc(II) Complex with N-Salicylidene-p-toluidine

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Chinese Journal of Structural Chemistry 2006年第5期25卷 609-615页

作者： zHAO Guo-Liang WEN Yi-Hang yu yu-Ye zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces College of Chemistry and Life Science Zhejiang Normal University Jinhua Zhejiang 321004 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China College of Vocation and Technology Jinhua Zhejiang 321017 China

The title complex, zn（C24H13NO）2Cl21, has been synthesized by the reaction of zinc chloride with Schiff base ligand N-salicylidene-p-toluidine and its structure was determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group Cc with a = 14.896（3）, b = 12.506（2）, c = 15.352（3） A,β = 114.711 （4）°, V = 2598.0（8） A^3, C28H26znCl2N2O2, Mr = 558.80, z = 4, Dc = 1 .429 g/cm^3,μ = 1.179 mm^-1, Flack parameter = 0.027（19）, F（000） = 1152, R = 0.0709 and wR = 0.1041 for 3117 observed reflections （Ⅰ 〉 2σ（Ⅰ））. In complex 1, the center zn ion is four-coordinated by two O atoms from two Schiff base ligands and two Cl atoms in a distorted tetrahedral geometry. Additionally, the thermal decomposition of complex 1 as well as its kinetic mechanisms and equations is studied under the non-isothermal integral and differential methods in air by TG-DTG curves.

关键词： zinc(Ⅱ) complex N-salicylidene-p-toluidine,crystal structure kinetic mechanism of thermal decomposition

Multibeam Raman amplification of a finite-duration seed in a short distance

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Chinese Physics B 2021年第10期30卷 428-435页

作者： Y G Chen Y Chen S X Xie N Peng J Q yu C z Xiao Key Laboratory for Micro-/Nano-Optoelectronic Devices of Ministry of Education School of Physics and ElectronicsHunan UniversityChangsha 410082China Collaborative Innovation Center of IFSA(CICIFSA) Shanghai Jiao Tong UniversityShanghai 200240China

A new scheme of multibeam Raman amplification(MRA)is proposed in virtue of the collective mode by sharing a common scattered *** laser beams can provide a higher growth rate,but the overlapping region limits the amplification *** suggest to use a finite-duration seed to facilitate MRA in a short *** two-dimensional particle-in-cell simulations,we find that two-beam Raman amplification has a much higher growth rate than that of singlebeam *** growth rate depends on the initial seed amplitude,electron temperature,and seed *** empirical criterion,γ0τc=1,whereγ0 is the theoretical growth rate of MRA,is used to choose a proper duration for a higher growth *** a total amplification length of 320µm,the two-beam Raman amplification shows nonlinear features of pulse compression and a bow-shape wave front,indicating that the amplification has finally entered the self-similar regime.

关键词： multibeam Raman amplification growth rate finite-duration

Exploiting comments information to improve legal public opinion news abstractive summarization

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Frontiers of Computer Science 2022年第6期16卷 31-40页

作者： yuxin HUang zhengtao yu Yan XIang zhiqiang yu Junjun GUO Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming650500China yunnan Key Laboratory of Artificial Intelligence Kunming University of Science and TechnologyKunming650500China

Automatically generating a brief summary for legal-related public opinion news(LPO-news,which contains legal words or phrases)plays an important role in rapid and effective public opinion *** LPO-news,the critical case elements which are significant parts of the summary may be mentioned several times in the reader ***,we investigate the task of comment-aware abstractive text summarization for LPO-news,which can generate salient summary by learning pivotal case elements from the reader *** this paper,we present a hierarchical comment-aware encoder(HCAE),which contains four components:1)a traditional sequenceto-sequence framework as our baseline;2)a selective denoising module to filter the noisy of comments and distinguish the case elements;3)a merge module by coupling the source article and comments to yield comment-aware context representation;4)a recoding module to capture the interaction among the source article words conditioned on the *** experiments are conducted on a large dataset of legal public opinion news collected from micro-blog,and results show that the proposed model outperforms several existing state-of-the-art baseline models under the ROUGE metrics.

关键词： legal public opinion news abstractive summarization comment comment-aware context case elements bidirectional attention

Solvothermal Synthesis, Crystal Structure and Characterization of a New Binuclear Copper(Ⅱ) Complex with K^(3):N^(1):N^(2):N^(4)-3-(Pyridin-2-yl)-1,2,4-triazole(HPT)

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Chinese Journal of Structural Chemistry 2021年第4期40卷 453-458,406页

作者： LI Chong-yu yu Peng School of Chemistry and Materials Science Hunan Agricultural UniversityChangsha 410128China

A new binuclear copper(Ⅱ)complex[Cu_(2)(MBBA)_(2)(HPT)_(2)(H_(2)O)_(2)]·2H_(2)O(1)was synthesized with copper acetate,2-(4-methylbenzoyl)benzoic acid(MBBA)and 3-(pyridin-2-yl)-1H-1,2,4-triazole(HPT).It crystallizes in the monoclinic space group P21/c with a=14.722(2),b=8.8907(12),c=18.5565(18)A,β=116.820(7)o,V=2167.6(5)A^(3),Mr=483.96,Dc=1.483 g/cm^(3),z=4,μ(Mo Ka)=1.049 mm^(-1),F(000)=981,the final GOOF=0.952,R=0.0586 and w R=*** whole molecule consists of two copper ions bridged by two HPT *** central Cu(Ⅱ)ion is coordinated by six atoms to give a distorted octahedral coordination *** structure of 1 has been determined by X-ray diffraction,IR spectrum and thermal stability *** solid-state fluorescence displays an obvious emission band at 412 nm upon excitation at 330 *** properties indicate that 1 exhibits antiferromagnetic properties.

关键词： binuclear copper(Ⅱ)complex thermal stability fluorescence magnetic property

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