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journal of Magnesium and Alloys 2021年第2期9卷 560-568页

作者： B.j.Wang D.K.xu x.Cai Y.x.Qiao l.Y.Sheng School of Environmental and Chemical Engineering Shenyang Ligong UniversityShenyang110159China Key laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiangChina Peking university Shenzhen InstituteShenzhen Key Lab Human Tissue Regenerate&RepairShenzhen 518057China

In this work,the influence of rolling ratios on microstructural changes and corrosion behavior of an as-rolled Mg-8 wt.%li alloy in0.1 mol/l Na Cl solution has been *** revealed that with the rolling ratio being increased from 3 to 10,theα-Mg phases were elongated and fragmented,whilst the area fraction of exposedβ-li phases ***,the corrosion performance of the alloy decreased with the increased rolling *** all the samples,their corrosion processes were quite similar and can have two *** the initial stage with the samples being immersed for less than 6 h,the corrosion mainly occurred inβ-li *** the samples were immersed for longer than 6 h,the corrosion attack transferred toα-Mg phases and the hydrogen evolution rate was accelerated.

关键词： Mg-li alloys Wrought Microstructure Corrosion performance

EFFECT OF SIlICON ADDITION ON RECRYSTAllIZATION AND PHASE TRANSFORMATION BEHAVIOR OF HIGH-STRENGTH HOT-ROllED TRIP STEEl

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Acta Metallurgica Sinica(English letters) 2008年第3期21卷 163-168页

作者： l.j. Zhu D. Wu x.M. Zhao College of Materials Science and Engineering Jilin University Changchun 130025 China The State Key laboratory of Rolling Technology and Automation Northeastern University Shenyang110004 China

Because Si is a noncarbide forming element, a multiphase microstructure consisting of ferrite, bainite, and retained austenite, at room temperature, can be formed by controlling the thermomechanical process strictly. The cooling schedules must be restricted by the formation of pearlite and cementite. In the present article, a new integrated mathematical model for prediction of microstructure evolution during controlled rolling and controlled cooling is developed for a typical kind of low carbon Si-Mn TRIP steel, which consists of temperature simulation, recrystallization, and transformation models. The influence of Si contents has been thoroughly investigated. The calculated results indicate that Si retards recrystallization, restrains austenite grain growth as well as accelerates polygonal ferrite transformation.

关键词： TRIP steel Recrystallization Ferrite transformation Bainite transformation Silicon

Effect of grain size on fatigue cracking at twin boundaries in a CoCrFeMnNi high-entropy alloy

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journal of Materials Science & Technology 2020年第4期39卷 1-6页

作者： A.G.Wang x.H.An j.Gu x.G.Wang l.l.li W.l.li M.Song Q.Q.Duan Z.F.Zhang x.Z.liao School of Aerospace Mechanical&Mechatronic EngineeringThe University of Sydne0ySydneyAustralia State Key laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Materials Fatigue and Fracture Division Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Max-Planck-Institut für Eisenforschung Max-Planck-Stra?e 140237 DüsseldorfGermany

The fatigue cracking behavior at twin boundaries(TBs)in a Co Cr Fe Mn Ni high-entropy alloy with three different grain sizes was systematically investigated under low-cycle *** of grain size,the change from slip band cracking to TB cracking occurred with increasing the difference in the Schmid factors(DSF)between matrix and ***,the required critical DSF for the transition of the dominant cracking mode decreases with decreasing grain size due to the reduced slip band spacing that increases the impingement sites on the TBs and facilitates the coalescence of defects and voids to initiate TB cracks.

关键词： High-entropy alloy Fatigue cracking Twin boundary Slip band Grain size

Nanocrystal Model for liquid Metals and Amorphous Metals

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journal of Materials Science & Technology 2010年第1期26卷 69-74页

作者： x.l. Tian, C.W. Zhan, j.x. Hou, x.C. Chen and j.j. Sun Key laboratory of liquid Structure and Heredity of Materials, Ministry of Education, Shandong university, jinan 250061, China Key laboratory of liquid Structure and Heredity of Materials Ministry of Education Shandong University Jinan 250061 China

A nanocrystal model for liquid metals and amorphous metals has been developed. With the nanocrystal model, the broadening peak profiles （BPPs） of Cu, Al, Al65Cu20Fe15 alloy, Cu7oNi30 alloy and Fe50Si50 alloy were gained by broadening the x-ray diffraction （xRD） peaks of a crystal lattice. By comparing the BPPs with the xRD intensity curves measured on the liquid metals, it is found that the BPPs are closely in agreement with the xRD intensity curves, respectively, except the FesoSiso alloy. Therefore, the nanocrystal model can be used to determine if the atomic cluster structure of the liquid metal is similar to the structure of its crystal lattice.

关键词： liquid metal Atomic cluster Structure Crystal lattice

Effect of Solidification Condition and Carbon Content on the Morphology of MC Carbide in Directionally Solidified Nickel-base Superalloys

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journal of Materials Science & Technology 2014年第12期30卷 1296-1300页

作者： x.W.li l.Wang j.S.Dong l.H.lou Superalloys Division Institute of Metal Research Chinese Academy of Sciences

Evolution of the morphology of MC carbides with the change of cooling rate and carbon content in two kinds of nickel-base superalloys, K417 G and DD33, has been investigated. The morphology of MC carbides evolves from faceted to script-like with increasing cooling rate. Varying the carbon content from 40x10-6 to 320x10-6, the morphology of carbides changes from blocky, rod-like into script-like. Scanning electron microscopy observation of deep-etched samples indicates that these carbides evolve from octahedral to dendritic and then into welldeveloped dendrites accordingly in a three-dimensional manner. The morphology evolution is discussed from the viewpoint of the preferential growth orientation of fcc crystals and the carbide growth rate during directional solidification.

关键词： Carbides morphology Directional solidification Three-dimensional microstructure Nickel-base superalloys

Giant Magneto-impedance Effect in Composite Wires with Different Core layer

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Nano-Micro letters 2013年第2期5卷 140-144页

作者： R.l.Wang x.li x.H.Kong Y.x.Guo j.Z.Ruan Z.j.Zhao Department of Physics Engineering Research Center for Nanophotonics & Advanced Instrument Ministry of Education East China Normal University Experimental Teaching Center of Physics Shanghai Ocean University

Composite structure materials were potential sensing elements for magnetic sensors due to Giant magnetoimpedance(GMI) effect. Two kinds of composite wires with different magnetic/non-magnetic structures were fabricated by using electroless deposition methods and the magnetoimpedance properties were investigated. The maximum GMI ratio of 114% was acquired at 60 MHz in the composite wires with a ferromagnetic core, whereas, 116% of maximum GMI ratio was found in the composite wires with a conductive core at low frequency of 600 k Hz. These results exhibit that the GMI ratio reaches the maximum when magnetoresistance ratio ?R/R and magnetoinductance ratio ?x/x make the comparative contributions to the total magnetoimpedance(MI). The obvious GMI effect obtained in the composite wires with conductive core frequency may provide a candidate for applications in magnetic sensors, especially at low frequencies.

关键词： Composite wires Electroless deposition Giant Magnetoimpedance effect Resistivity

NuMERICAl SIMulATION OF CASTING'S MOlD FIllING PROCESS

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Acta Metallurgica Sinica(English letters) 2005年第6期18卷 724-730页

作者： j.x. Zhou R.x. liu l.l. Chen D.M. liao H. S. Wei State Key lab of Die and Mold Technology Huazhong University of Science and Technology Wuhan 430074 China

Numerical simulation of casting＇s mold filling process is the main and the most important aspect of the foundry CAE technology. But it is time-consuming; it may take dozens of hours or several days. While with the development of computer hardware, numerical simulation of casting＇ s mold filling process has made rapid progress. The simulation results, therefore, have become more and more practical. This study tries to find some clues of the computational time of mold filling process. Firstly, this paper introduces mathematic model and the basic route of numerical simulation of casting＇s mold filling process. Then the computational time of mold filling process has been carefully studied, and some new and useful results have been gained from the study of the computational time. Finally, this paper has given some real applications of numerical simulation of casting＇s mold filling process.

关键词： numerical simulation mold filling process casting

通过深度学习预测脑膜瘤的等级和病理标志物表达

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国际医学放射学杂志 2024年第4期 496-497页

作者： j.W.Chen Y.P.xue l.H.Ren K.lv P.Du H.x.Cheng 胡佳圆

摘要目的建立一个深度学习（Dl）模型用于预测脑膜瘤的肿瘤等级和病理标志物的表达。方法回顾性纳入2018年9月—2021年12月在2家医院接受手术切除的1 192例

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BaTiO_(3)solid solutions co-doped with Gd^(3+)and Eu^(3+):Synthesis,structural evolution and dielectric properties

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journal of Rare Earths 2024年第10期42卷 1920-1926页

作者： R.Martínez-lópez M.Pérez-labra j.A.Romero-Serrano F.R.Barrientos-Hernández M.Reyes-Pérez M.I.Valenzuela-Carrillo G.urbano-Reyes V.E.Reyes-Cruz G.I.Dávila-Pulido Academic Area of Earth Sciences and Materials Autonomous University of Hidalgo StateRoad Pachuca-Tulancingo Km 4.5 Mineral de La Reforma.Hidalgo42184Mexico Metallurgy and Materials Department ESIQIE-IPNUPALMZacatencoCiudad de Mexico07738Mexico Autonomous university of Coahuila Boulevard Adolfo López Mateos S/nNueva RositaCoahuila26800Mexico

In this paper,the synthesis,structural evolution,and dielectric properties of BaTiO_(3)solid solutions codoped with rare earth elements(Gd^(3+)and Eu^(3+))prepared using the solid-state reaction method are *** pure precursor powders of BaCl_3,TiO_(2),Gd_(2)O_(3),and Eu_(2)O_(3)were mixed in stoichiometric proportions,ground in an agate mortar before being uniaxially pressed at 250 MPa and sintered at 1300℃in air atmosphere for 6 h to obtain Ba_(1-3x)Gd_(2x)Ti_(1-3x)Eu_(4x)O_(3)(x=0,0.0015,0.01 and0.1).x-ray diffraction(xRD)and Rietveld's refinement results reveal the crystal phase ferroelectric tetragonal BaTiO_(3)for the samples with x=0,0.0015 and 0.01,as well as a consistent increment in the lattice parameters caused by the *** solubility limit of Gd^(3+)and Eu^(3+)in the BaTiO_(3)structure is reached for the sample with x>0.01,and the orthorhombic Eu_2TiO_(5)and monoclinic BaTi_(2)O_(5)secondary phases were *** Raman results show the characteristic peaks of ferroelectric tetragonal BaTiO_(3)around 716 cm^(-1)(lO of A1 symmetry),515 cm^(-1)(TO of A1 symmetry),and 305 cm^(-1)(B1).The maximum relative permittivity measured at 1 kHz was recorded to be 6151.8 for the sample with x=0.0015,and a decrease in the Curie temperature to 105℃with respect to the undoped sample was *** punctual microanalysis for the samples with x=0.0015,0.01,and 0.1 reveals grains composed of Ba,Ti,O,Gd,and Eu homogeneously distributed in the BaTiO_(3)*** Ba/Ti ratios for samples with x=0.0015,0.01 and 0.1 are 2.86,2.91,and 0.68,respectively,indicating substitution at the Ti site for samples with x=0.0015 and 0.01 and a substitution at the Ba site for the sample with x=0.1.

关键词： BaTiO_(3) Doping Gadolinium Europium Synthesis Rare earths

流域水力侵蚀碳汇效应对土壤碳流失的平衡作用

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中国科学：地球科学 2024年第6期54卷 2050-2064页

作者：王凌霞聂小东李嘉奇刘窑军王惠李雅喆李忠武湖南师范大学地理科学学院长沙410081 湖南师范大学交叉科学研究院洞庭湖流域生态环境变化与固碳增汇湖南省重点实验室长沙410081 湖南大学环境科学与工程学院环境生物与控制教育部重点实验室(湖南大学)长沙410082

明确土壤碳循环过程及其主控因素,是估算和提升土壤固碳能力的重要前提.本文在流域尺度上探究了水力侵蚀在土壤碳循环中扮演的“源汇”角色.通过耦合空间分布式泥沙输移模型与生物地球化学模型,提出了一种定量估算水力侵蚀驱动下土壤有... 详细信息

明确土壤碳循环过程及其主控因素,是估算和提升土壤固碳能力的重要前提.本文在流域尺度上探究了水力侵蚀在土壤碳循环中扮演的“源汇”角色.通过耦合空间分布式泥沙输移模型与生物地球化学模型,提出了一种定量估算水力侵蚀驱动下土壤有机碳横向迁移和垂向通量的方法.将该耦合模型应用于洞庭湖流域,结果表明:1980~2020年间洞庭湖流域年均土壤侵蚀量为1.33×10^(8)t,呈先减后增的趋势.水力侵蚀驱动下,仅有12%发生迁移的有机碳最终流入河流系统,其余均随泥沙在流域陆上沉积并被埋藏.水力侵蚀造成的土壤有机碳横向流失量在1980年为8.86×10^(11)g C, 2020年为1.50×10^(11)g C,减少了83%.侵蚀过程中由于沉积泥沙的埋藏作用和土壤碳的动态置换,土壤有机碳垂向通量呈现5.54×10^(11)g C a^(-1)的净碳汇. 40年间土壤有机碳横向流失量减少及侵蚀引起净碳汇量增加源于大规模生态恢复工程的实施和耕作方式的改良,其对于减少水土流失和提高土壤碳储量具有重要意义.本研究提出的耦合模型可在大空间尺度和长时间段内对侵蚀引起的土壤碳动态过程进行空间显式模拟,为预测未来气候和土地利用变化下土壤碳储量提供科学支撑.

关键词：水力侵蚀泥沙输移横向土壤碳流失陆地-大气CO_(2)通量洞庭湖流域