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Microwave sintered porous CoCrFeNiMo high entropy alloy as an efficient electrocatalyst for alkaline oxygen evolution reaction

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Journal of Materials Science & Technology 2021年第20期79卷 171-177页

作者： J.Tang J.l.xu z.G.Ye x.B.li J.M.luo School of Materials Science and Engineering Nanchang Hangkong UniversityNanchang330063China

Developing efficient,stable and economical electrocatalyst for oxygen evolution reaction(OER)is a significant pathway to produce clean energy from water ***,the promising and highly efficient porous CoCrFeNiMo high entropy alloys(HEAs)were prepared by microwave sintering using Mg space *** to unique properties of high entropy alloys and abundant active surface area,the porous CoCrFeNiMo-20 Mg exhibits excellent catalytic performance and prominent electrochemical stability with a low overpotential of 220 mV to reach current density of 10 mA cm^(-2),a small Tafel slope of 59.0 mV dec^(-1) and long-term durability for 24 h in 1.0 M *** results of microstructure and element states indicate that crystal defects,porous structure and villous hydroxides are the reasons for high OER performance of the *** work not only provides a new way to prepare electrocatalysts,but also proves the important application of high entropy alloys in functional materials.

关键词： CoCrFeNiMo High entropy alloys Electrocatalysts Oxygen evolution reaction Microwave sintering Mg space holder

Examining the effect of the aging state on strength and plasticity of wrought aluminum alloys

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Journal of Materials Science & Technology 2022年第27期122卷 54-67页

作者： z.Qu z.J.zhang J.x.Yan P.zhang B.S.Gong S.l.lu z.F.zhang T.G.langdon Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Department of Mechanical Engineering University of SouthamptonSouthampton SO171BJUnited Kingdom

A general rule of strength and plasticity was proposed for three typical wrought Al alloys(2xxx,6xxx,and 7xxx)subjected to different aging *** of the work-hardening processes and dislocation configurations in tensile and compressive testing reveal that this general rule arises because there is a common mechanism for these three kinds of wrought alloys whereby the tendency for cross-slip increases monotonously with aging *** analyzing the strain hardening exponent and the stacking fault energy,it is demonstrated that the change in the dislocation slip mode is attributed mainly to the formation of second phases rather than to the matrix ***,a new work-hardening model was proposed for wrought Al alloys containing second phases and this explains the interaction between dislocations and second phases and other relevant experimental *** work is therefore beneficial for quantitatively investigating and optimizing the strength and plasticity of wrought aluminum alloys.

关键词： Wrought aluminum alloy Strength and plasticity Work hardening Dislocation slip mode Second phase

Accident of large-scale Wind Turbines Disconnecting from Power Grid and Its Protection

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电力系统自动化 2012年第8期36卷 105-109页

作者： Dong, x.z. Shi, S.x. Wang, B. Bak, D.J. Cao, R.B. Ren, l. lan, l. He, S.E. State Key lab. of Power Systems Department of Electrical Engineering Tsinghua University Beijing 100084 China Wind Power Technology Center Gansu Electric Power Corporation Lanzhou 730050 China

There were many accidents of large-scale wind turbines disconnecting from power grid in *** singlephase-to-ground fault cannot be correctly detected,single-phase-to-ground fault evolved to phase-to-phase ***-to-phase fault was isolated slowly,thus leading to low *** wind turbines without enough low voltage ride-through capacity had to be disconnected from the *** some wind turbines being disconnected from the grid,overvoltage caused by reactive power surplus made more wind turbines disconnect from the *** on the accident analysis,this paper presents solutions to above problems,including travelling waves based single-phase-to-ground protection,adaptive low voltage protection,integrated protection and control,and high impedance fault *** solutions lay foundations in theory and technology to prevent large-scale wind turbines disconnecting from the operating power grid.

关键词：大型风力发电机组低电压保护电网事故断开单相接地故障风力涡轮机故障检测切断电源

Magneto-Impedance Effect of Composite Wires Prepared by Chemical Plating under DC Current

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Nano-Micro letters 2014年第3期6卷 227-232页

作者： D.l.Chen x.li H.l.Pan H.Y.luan z.J.zhao Department of Physics Engineering Research Center for Nanophotonics & Advanced Instrument Ministry of Education East China Normal University

CuBe composite wires of 100 μm in diameter coated with a layer of NiCoP were prepared by a chemical plating method under DC current(CPuDC). The influences of DC current on coating morphology,deposition rate, composition, giant magneto-impedance(GMI) effect and magnetic properties were *** was shown that the circumferential domain structure of coating layer was induced by the DC current going through the wires. A maximum GMI ratio of 870% was obtained in the composite wire prepared under 150 m A and tested at 180 k Hz. It is 30 times higher than that of the composite wire plated in the same condition by conventional chemical plating method, indicating that CPuDC is an easy and effective approach to obtain composite wires and its applications will be further extended on magnetic sensors.

关键词： GMI Chemical plating Magnetic properties

Sample selection for models to represent ceramic cores fabricated by stereolithography three-dimensional printing

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Journal of Materials Science & Technology 2022年第26期121卷 117-123页

作者： x.l.An J.J.liang J.G.li J.W.Chen Y.z.zhou x.F.Sun School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Space Manufacturing Technology(CAS Key lab) Beijing 100094China

Ceramic cores with good chemical stability and moderate mechanical properties near casting temperatures of 1550℃ for example are used for the manufacturing of internal structures of hollow blades,requiring complex structures and high precision[1–3].However,traditional preparation method based on investment casting is tedious,requiring not only long production cycles but also high cost[4].

关键词： investment printing ceramic

lOW CYClE FATIGuE AND CREEP-FATIGuE BEHAVIOR OF A HIGH TEMPERATuRE AllOY ON SMOOTH AND NOTCHED SPECIMENS

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Acta Metallurgica Sinica(English letters) 1999年第1期12卷 40-45页

作者： Shi, H.J. liu, S.l. He, Y.H. Duan, z.x. Tsinghua univ Beijing China

A series of low cycle fatigue and creepfatigue tests on smooth specimens and notched specimens were performed with a high temperature alloy used in the manufacture of aeroengine turbine discs. The cyclic stressstrain behavior and fracture characteristics of the notched specimens were emphatically investigated. A comparison of fatigue behavior between smooth and notched specimens was done and lifetime of notched specimens was evaluated. At the same temperature, the fatiguecreep lives of the smooth specimens are far greater than that of the notched specimens.

关键词： low cycle fatigue creepfatigue stress concentration notch effect

Superb Strengthening Effect of Net-like Distributed Amorphous Al_(2)O_(3)on Creep Resistance of(B_(4)C+Al_(2)O_(3))/Al Neutron-Absorbing Materials

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Acta Metallurgica Sinica(English letters) 2022年第12期35卷 2007-2013页

作者： Y.N.zan x.lei J.F.zhang D.Wang Q.z.Wang B.l.xiao z.Y.Ma Key laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.LtdBejing 100840China

B4C reinforced Al composites are widely used as neutron absorbing materials(NAMs)due to excellent neutron absorbing efficiency,however,such NAMs exhibit poor high-temperature *** meet the requirement for structure-function integration,NAMs with enhanced high-temperature mechanical properties are *** this work,a novel(B4 C+Al_(2)O_(3))/Al NAM with netlike distribution of Al_(2)O_(3)was fabricated by powder metallurgy method and subjected to high-temperature tensile creep *** was shown that the creep resistance was enhanced by several orders of magnitude via the addition of only2.1 vol.%netlike-distributed Al_(2)O_(3).(B_(4)C+Al_(2)O_(3))/Al exhibited high apparent stress exponents ranging from 16 to 25 and high apparent activation energy of 364 kJ/*** creep behaviour could be rationalized using the substructure-invariant model and its rupture behaviour could be described by the Dobes-Milicka equation.

关键词： Neutron absorber material Al matrix composite Tensile creep B_(4)C/Al

Studies of Optical Nonlinearity Behaviors of ultrafine PbS Particles in Perfluorocarboxylated Cation-exchanged Films

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High Technology letters 1995年第1期1卷 102-104页

作者： xiaowen, zh. xueping, l. Yuan, l. xurui, x. Songbin, zh. zongju, x. Yinghua, z. Academia Sinica Beijing China

ultrafine PbS particles with different sizes have been prepared in perfluorocarboxylated cation-exchanged films. The variation of PbS particle size was clarified by absorption spectra and TEM graphs. Time-resolved optical Kerr effects were measured by femtosecond pump-probe techniques. Optical Kerr effect response time was estimated to be less than 165 fs. A third-order optical nonlinearity of χ(3)10-12 esu for PbS particles was obtained and it was found that it increases with the decrease of particle sizes, showing the influence of quantum confined effect on optical nonlinear behaviour of ultrafine particles.

关键词： PbS ultrafine particle Optical nonlinearity Optical Kerr effect

Quantized Conductance of Majorana zero Mode in the Vortex of the Topological Superconductor(li_(0.84)Fe_(0.16))OHFeSe

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Chinese Physics letters 2019年第5期36卷 90-97页

作者： C.Chen Q.liu T.z.zhang D.li P.P.Shen x.l.Dong z.-x.zhao T.zhang D.l.Feng State Key laboratory of Surface Physics and Department of Physics Fudan UniversityShanghai 200433 Collaborative Innovation Center of Advanced Microstructures Nanjing 210093 Science and Technology on Surface Physics and Chemistry laboratory Mianyang 621908 National laboratory of Superconductivity Institute of PhysicsChinese Academy of SciencesBeijing 100190 Hefei National laboratory for Physical Science at Microscale CAS Center for Excellence in Quantum Information and Quantum Physicsand Department of PhysicsUniversity of Science and Technology of ChinaHefei 230026

The Major ana zero mode(MzM), which manifests as an exotic neutral excitation in superconductors, is the building block of topological quantum computing. It has recently been found in the vortices of several iron-based superconductors as a zero-bias conductance peak in tunneling spectroscopy. In particular, a clean and robust MzM has been observed in the cores of free vortices in(li_(0.84)Fe_(0.16))OHFeSe. Here using scanning tunneling spectroscopy, we demonstrate that Major ana-induced resonant Andreev reflection occurs between the STM tip and this zero-bias bound state,and consequently, the conductance at zero bias is quantized as 2e^2/h. Our results present a hallmark signature of the MzM in the vortex of an intrinsic topological superconductor, together with its intriguing behavior.

关键词： OHFeSe Quantized Conductance of Majorana zero Mode in the Vortex of the Topological Superconductor MzM li STM Fe