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Chinese Journal of Polymer Science 2007年第6期25卷 641-649页

作者： Han Peng xiu-wen Zheng Jacky W. y. Lam Ben-zhong Tang Institute of Material Science and Engineering South China University of Technology Guangzhou 510640 China Department of Chemistry Hong Kong University of Science ＆ Technology Clear Water Bay Kowloon Hong Kong China

New hyperbranched poly（aryleneethynylene）s containing carbazole moieties are synthesized in high yields （up to 87%） by polycyclotrimerization of 3,6-bis（4-ethynylphenyl）-9-octylcarbazole and its copolymerization with 1-octyne catalyzed by CpCo（CO）2 in THF. The structures and properties of the polymers are characterized and evaluated by IR, NMR, TGA, UV, photoluminescence, and cyclic voltammetry analyses. All the polymers are soluble in common organic solvents and show outstanding thermal stability （≥ 430℃）. They graphitize in high yields （up to 79%） when pyrolyzed at 800℃. Upon photoexcitation, the polymers emit a strong deep blue light of ca. 400 nm with quantum yields larger than 60%.

关键词： Acetylenes Carbazole Cyclopolymerization Hyperbranched Luminescence.

Effect of Bismuth on Intermetallic Compound Growth in Lead Free Solder/Cu Microelectronic Interconnect

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Journal of Materials Science & Technology 2011年第8期27卷 741-745页

作者： T.y. Kang y. y. xiu L. Hui J.J. Wang W.P. Tong C.Z. Liu Key Laboratory of Electromagnetic Processing of Materials Ministry of Education Northeastern University Shenyang 110004 China Shenyang Aerospace University Shenyang 110136 China

The intermetallic compound （IMC） growth kinetics in pure Sn/Cu and Sn10 wt%Bi/Cu solder joints was studied, respectively, after they were aged at 160-210℃ for different time. It was found that the total IMC in Sn10 wt%Bi/Cu joint developed faster than it did in pure Sn/Cu solder joint, when they were aged at the same temperature. And the activation energy Qa for total IMC in Sn10 wt%Bi/Cu joint was lower than that for pure Sn/Cu interconnect. The IMC growth process was discussed. The IMC Cu6Sn5 was enhanced in compensation of reduced IMC Cu3Sn growth. The work reveals that Bi element containing in lead free solder alloys with 10 wt% can enhance IMC growth in lead free solder/Cu joint during service.

关键词： Solder Interfacial reaction Intermetallics Kinetics

Skyrmion-(non)crystal structure stabilized by dipolar interaction

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Rare Metals 2022年第9期41卷 3160-3169页

作者： Ming-xiu Sui yong Hu Department of Physics College of SciencesNortheastern UniversityShenyang110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819China

We report a numerical study on the role of longrange dipolar interaction played on the creation and stabilization of skyrmion-(non)crystal structure in chiral ferromagnetic thin films without any anisotropies,based on a Monte-Carlo simulation *** the increase of external magnetic field,the microscopic spin configuration is transformed from a spin-spiral stripe or labyrinth structure,depending on the strength of dipolar interaction,into a skyrmion-(non)crystal structure,and then into a skyrmiongas structure,and finally into a ferromagnetic ***,with the increase of dipolar interaction,the skyrmion-crystal structure evolves from a triangular arrangement into a square arrangement with the change of skyrmion shape from circle to *** larger dipolar interactions,the skyrmion-crystal structure loses the regular arrangements and the skyrmions,remaining topological,exhibit different shapes and sizes and squeeze with each other,whose distributions are analogous to a non-crystal ***,different skyrmion-(non)crystal structures are stabilized in different ranges of dipolar interactions,which further promotes the applications of skyrmions as non-volatile information carriers.

关键词： Chiral ferromagnetic thin film Skyrmion(non)crystal structure Interfacial Dzyaloshinskii-Moriya interaction Dipolar interaction Monte-Carlo simulation

Interaction solutions to Hirota-Satsuma-Ito equation in (2+1)-dimensions

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Frontiers of Mathematics in China 2019年第3期14卷 619-629页

作者： Wen-xiu MA Department of Mathematics Zhejiang Normal University Jinhua 321004 China Department of Mathematics King Abdulaziz University Jeddah Saudi Arabia Department of Mathematics and Statistics University of South Florida Tampa FL 33620 USA College of Mathematics and Physics Shanghai University of Electric Power Shanghai 200090 China College of Mathematics and Systems Science Shandong University of Science and Technology Qingdao 266590 China Department of Mathematical Sciences North-West University Mafikeng Campus Mmabatho 2735 South Africa

Abundant exact interaction solutions, including lump-soliton, lump-kink, and lump-periodic solutions, are computed for the Hirota-Satsuma-Ito equation in (2+1)-dimensions, through conducting symbolic computations with Maple. The basic starting point is a Hirota bilinear form of the Hirota-Satsuma-Ito equation. A few three-dimensional plots and contour plots of three special presented solutions are made to shed light on the characteristic of interaction solutions.

关键词： Symbolic computation lump solution interaction solution

A Nontrivial Product of Filtration s+5 in the Stable Homotopy of Spheres

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Acta Mathematica Sinica,English Series 2007年第3期23卷 385-392页

作者： xiu Gui LIU Department of Mathematics and LPMC Nankai University Tianjin 300071 P. R. China

In this paper, some groups Ext A^s.t （Zp, Zp） with specialized s and t are first computed by the May spectrM sequence. Then we make use of the Adams spectral sequence to prove the existence of a new nontrivial family of filtration s＋5 in the stable homotopy groups of spheres πpnq＋（s＋3）pq＋（s＋1）q-5S which is represented （up to a nonzero scalar） by β＋2bohh∈ExtA^s＋5,P^nq＋（n＋3）pq＋（n＋1）q＋s（Zp, Zp） in the Adams spectral sequence, where p ≥ 5 is a prime number, n ≥3, 0≤ s 〈 p - 3, q = 2（p - 1）.

关键词： Stable homotopy of spheres Adams spectral sequence Toda Smith spectrum May spectral sequence

A Note on the Mean Value of Numbers of the Solutions of x~α=1(mod n)

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Acta Mathematica Sinica,English Series 2004年第6期20卷 1095-1102页

作者： xiu yuan yU Department of Mathematics Hangzhou Teachers' College Department of Mathematics Quzhou College

Let T=T(p,q,α) be the number of solutions of the congruence x~α≡1 (rood p^nq~θ).Let A and B be sets of primes satisfying x_1x_2 and y_1y_2,respectively.A mean value estimation of (?)∑_(p∈A)∑_(q∈B) logT... 详细信息

关键词： Congruence Number of solutions Mean value

Structural characteristics,dispersion,and modification of fibrous brucite

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International Journal of Minerals,Metallurgy and Materials 2014年第1期21卷 82-88页

作者： xi Cao xiu-yun Chuan Key Laboratory of Orogen and Crust Evolution of the Education Ministry of China School of Earth and Space SciencesPeking University

Fibrous bmcite has very unique structure and physical properties. Brucite fibers were exfoliated into single nanofibers by using dioctyl sodium sulfosuccinate （AOT） as a dispersant through mechanical agitation and ultrasonic dispersion; and then, the nanofibers were modified by stearic acid and （3-aminopropyl）triethoxysilane （y-APS） compound modification agent. The nanofibers were characterized by using x-ray diffraction （xRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, Fourier transform infrared spectroscopy （FTIR）, and thermal gravimetric analysis. It is found that AOT has good effect on the dispersion. The single fiber has a consis- tent morphology, and fibrous bmcite is dispersed and modified without destroying the crystal structure. Infrared and thermal analysis shows that the surface modification of fibrous brucite is achieved by forming chemical bonds between the coupling agent and magnesium hydroxide.

关键词： fibrous brucite dispersion nanofibers surface treatment modification

Lateral Global Buckling of Submarine Pipelines Based on the Model of Nonlinear Pipe–Soil Interaction

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China Ocean Engineering 2018年第3期32卷 312-322页

作者： LIU Run WANG xiu-yan State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University

With the increasing development and utilization of offshore oil and gas resources, global buckling failures of pipelines subjected to high temperature and high pressure are becoming increasingly important. For unburied or semi-buried submarine pipelines, lateral global buckling represents the main form of global buckling. The pipe–soil interaction determines the deformation and stress distribution of buckling pipelines. In this paper, the nonlinear pipe–soil interaction model is introduced into the analysis of pipeline lateral global buckling, a coupling method of PSI elements and the modified RIKS algorithm is proposed to study the lateral global buckling of a pipeline, and the buckling characteristics of submarine pipeline with a single arch symmetric initial imperfection under different pipe–soil interaction models are studied. Research shows that, compared with the ideal elastic–plastic pipe–soil interaction model, when the DNV-RP-F109 model is adopted to simulate the lateral pipe–soil interactions in the lateral global buckling of a pipeline, the buckling amplitude increases, however, the critical buckling force and the initial buckling temperature difference decreases. In the DNV-RP-F109 pipe–soil interaction model, the maximum soil resistance, the residual soil resistance, and the displacement to reach the maximum soil resistance have significant effects on the analysis results of pipeline global buckling.

关键词： submarine pipeline lateral global buckling PSI element nonlinear pipe–soil interaction

A review of the strengthening–toughening behavior and mechanisms of advanced structural materials by multifield coupling treatment

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International Journal of Minerals,Metallurgy and Materials 2022年第2期29卷 185-199页

作者： xiu Song Lei Wang yang Liu The Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China

The application of an external field is a promising method to control the microstructure of materials, leading to their improved performance. In the present paper, the strengthening and toughening behavior of some typical high-performance structural materials subjected to multifield coupling treatment, including electrostatic field, electro-pulse current, thermal field, and stress field, are reviewed in detail. In addition to the general observation that the plasticity of materials could be increased by multi-external fields, strength enhancement can be achieved by controlling atomic diffusion or phase transformations. The paper is not limited to the strengthening and toughening mechanisms of the multifield coupling effects on different types of structural materials but is intended to provide a generic method to improve both the strength and ductility of the materials. Finally, the prospects of the applications of multi-external fields have also been proposed based on current works.

关键词： multifield coupling structural materials strengthening toughening microstructure