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STUDY OF THE INFLUENCE OF pH ON THE ELECTROCRYSTALLIzATION OF zINC

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 497-504页

作者： z. zhang W.H. Leng J. q. zhang Department of Chemistry Zhejiang University Hangzhou 310027 China State Key Laboratory for Corrosion and Protection Institute of Metal Reseach The Chinese Academy of Sciences Shenyang 110016 China

The influence of pH value of the electrolyte solution on the zinc electroplating process was studied by means of cyclic voltammetry and chronoamperometry approaches. The results shown that, under this experimental conditions and at high overpotentials, the nucleation of zinc is instantaneous, and the nuclear densities N increase with the overpotentials. While at low potentials, no distinguished nucleation current can be observed. High pH promotes the deposition either by drifting the initial depositing potential positively, or by increasing the depositing current through the change of the total charge of the adsorption process qads, i.e., thevstructure of electrochemical double layer.

关键词： zinc electroplating nucleation growth mechanism

Designing ultrastrong maraging stainless steels with improved uniform plastic strain via controlled precipitation of coherent nanoparticles

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Journal of Materials Science & Technology 2021年第34期93卷 60-70页

作者： z.H.wang B.Niu q.wang C.Dong J.C.Jie T.M.wang T.g.Nieh Key Laboratory of Materials Modification by Laser Ion and Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Department of Materials Science and Engineering The University of TennesseeKnoxville37996TennesseeUSA

The development of ultrastrong maraging stainless steels(MSSs)is always in high ***,traditional high-strength MSSs generally exhibit early plastic instability with a low uniform strain since the precipitated nanoparticles are non-coherent with the body-centered-cubic(BCC)lath martensitic ***,we design a novel ultrahigh strength MSS(Fe-5.30 Cr-13.47 Ni-3.10 Al-1.22 Mo-0.50 W-0.23 Nb-0.03 C-0.005 B,wt.%)using a cluster formula approach.A fabulous microstructure consisting of a uniform distribution of high-density coherent B2-Ni Al nanoprecipitates(3-5 nm)in BCC martensitic matrix was successfully *** alloy has not only an exceedingly high ultimate tensile strength of 2.0 gPa,but also a decent uniform elongation of 4.2%-5.1%,which is almost triple of the value observed in existing *** present an in-depth discussion on the origins of ultrahigh strength and uniform plastic strain in the new alloy to validate our design strategy and further offer a new pathway to exploit highperformance MSSs.

关键词： Maraging stainless steel Ultrahigh strength Coherent precipitation Strengthening mechanisms Uniform deformation

联合InSAR和gNSS构建青藏高原千米分辨率三维地壳形变场

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中国科学：地球科学 2024年第6期54卷 1845-1862页

作者：刘传金季灵运朱良玉许才军赵超英 zhong LU 王庆良武汉大学测绘学院武汉430079 中国地震局第二监测中心西安710054 长安大学地质工程与测绘学院西安710054 Roy M.Huffington Department of Earth Sciences Southern Methodist UniversityDallasTX 75025USA

青藏高原位于印度板块与欧亚板块碰撞的前沿地带,地壳运动十分活跃.受高海拔、高寒气候等因素的限制,以地面观测站为代表的传统大地测量监测较为困难,因此至今青藏高原的高空间分辨率地壳形变场尚未精确测定. InSAR技术不受地面观测条... 详细信息

青藏高原位于印度板块与欧亚板块碰撞的前沿地带,地壳运动十分活跃.受高海拔、高寒气候等因素的限制,以地面观测站为代表的传统大地测量监测较为困难,因此至今青藏高原的高空间分辨率地壳形变场尚未精确测定. InSAR技术不受地面观测条件限制,能够获得大范围、高空间分辨率的地壳形变场,在青藏高原地壳形变监测领域具有不可替代的优势.本文利用2014~2020年的Sentinel-1卫星SAR数据,计算了青藏高原升降轨InSAR形变场,测量精度约为3mm/a.在此基础上,融合InSAR与gNSS数据,获取了覆盖青藏高原的千米分辨率三维地壳形变场和应变率场.通过球面小波多尺度分析,将三维形变场分解出不同波长的形变,其中波长小于110km的形变主要来自断层运动、震后形变和其他非构造形变,大于110km的形变主要来自大范围的构造运动.研究结果显示,高原中部地区呈现大范围下沉,而喜马拉雅弧地区则呈现明显隆升,这表明青藏高原可能已经停止了整体隆升并进入了局部坍塌阶段.此外,不同空间尺度的三维形变场表明,青藏高原在短波长变形中表现为非连续形变,在长波长中则表现为连续形变.本文研究结果有助于调节青藏高原块体变形模型和连续变形模型之间的争议.

关键词：青藏高原 InSAR gNSS 三维形变形变模型

SYNTHESIS AND IDENTIFICATION OF CONDUCTINg POLYANILINE DOPED WITH RARE EARTH CHLORIDE

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Acta Metallurgica Sinica(English Letters) 2000年第3期13卷 872-876页

作者： Yang, C.M. zhang, q.R. Fang, z. Central South Univ of Technology Changsha China

Polyaniline doped with rare earth chloride was synthesized in organic solvent and identified by elemental analysis and infrared spectroscopy. The experimental results show that there exists both doping and complexation at the same time in the resulting product. When pH4. Moreover, polyaniline doped with rare earth chloride exhibits better thermal stability than that doped with hydrochloric acid.

关键词： Chlorine compounds Composition Conductive materials Electric conductivity Organic polymers Rare earth compounds Synthesis (chemical)

Flux Adjustable Permanent Magnet Machines:A Technology Status Review

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Chinese Journal of Electrical Engineering 2016年第2期2卷 14-30页

作者： Hui Yang z.q.zhu Heyun Lin Wenqiang Chu School of Electrical Engineering Southeast UniversityNanjing210096China Department of Electronic and Electrical Engineering University of SheffieldSheffield SI 3JDU.K.

Flux adjustable permanent magnet machines(FAPMMs)are a novel type of permanent magnet(PM)machines which are able to flexibly adjust the field excitation flux linkage and offer the distinctive advantages of high power density and high *** have attracted ever-increasing interests and are promising candidate machines for electric vehicle,machine-tool and aircraft *** this paper,the state-of-the-art of various FAPMMs are comprehensively reviewed according to three means of flux-adjustment,*** adjusted by either auxiliary field windings or armature winding change,mechanically adjusted magnetic reluctances of flux paths,and memory machines by magnetizing/demagnetizing *** corresponding flux-adjustable principles and electromagnetic characteristics are systematically elaborated and quantitatively *** merits and demerits are highlighted,together with their recent developments.

关键词： Flux-adjustable hybrid excitation memory machine mechanical adjustment permanent magnet machine winding change

Magnetic/Magnetostrictive Properties Together with Resistivity and Corrosion Behaviors of CoFe_2 and Its Composite with CoFe_2N

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Journal of Materials Science & Technology 2017年第7期33卷 744-750页

作者： B.q.geng Y.q.Ma M.wang z.L.Ding W.H.Song B.C.zhao Key Laboratory of Materials Physics Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China

The CoFe_2alloy（CF） was prepared by reducing CoFe_2O_4 in the H_2 ambient. Subsequently the CF sample was nitrided in the NH_3 atmosphere to produce the composite of CoFe_2N and CoFe_2. The magnetostriction, thermal expansion, resistivity and corrosion resistance of CF sample and the nitrided sample（CFN）at 1000？C were investigated. The saturation magnetostriction coefficiency λ_s and thermal expansion coefficient ？ at 300 K for the nitrided CFN were 50 ppm and 10 ppm/K, respectively, approximately equal to those for the CF sample. However, compared with CF, CFN presents a decrease in temperature coefficient R_λ（300 K） of magnetostriction by 11%. The smaller resistivity and improved corrosion resistance in the H_2SO_4 solution may expand the applications of the CoFe_2 in the fields needing lower resistivity or in the acidic environment.

关键词： CoFe alloy CoFe_2N alloy Magnetostriction Resistivity Corrosion resistance

ELECTROCHEMICAL NOISE ANALYSIS OF THE INFLUENCE OF THE zn^(2+)IONS CONCENTRATION ON zINC ELECTROPLATINg

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Acta Metallurgica Sinica(English Letters) 2005年第2期18卷 137-144页

作者： z.zhang C.S.Wu q.Y.Cai F.H.Cao J.q.zhang DepartmentofChemistry ZhejiangUniversityHangzhou310027China DepartmentofChemistry ZhejiangUniversityHangzhou310027China／／StateKeyLaboratoryforCorrosionandProtectionInstituteofMetalResearchTheChineseAcademyofSciencesShenyang110016China

The influence of the concentration of zn2+ ions on zinc electroplating process was investigated by means of electrochemical noise (EN) and cyclic voltammetry methods in conjunction with the scanning electron microscopy (SEM) technique. It was found that the EN generated during the electroplating of dentritic or large polymeric zinc deposit has large potential oscillation amplitude and positive potential drift while the compact zinc deposit possesses small noise amplitude and little potential drift. With the change of rate determining step from diffusion-control through mixed-control to activation-control, the maximum relative energy obtained from wavelet analysis defined from the region with larger scales to those with smaller scales, and the EDP (relative energy distribution plot) can be us, as 'fingerprints' of EN to characterize the electroplating process and the deposit structure. The results also showed that electrochemical noise technique can give more information about the electrodeposit structure than other normal electrochemical measurements, such as linear potential sweep method and cyclic voltammetry technique.

关键词： zinc electroplating zinc ions concentration electrochemical noise electrodeposit structure

MODELINg OF STATIC RECRYSTALLIzATION KINETICS OF Nb-BEARINg STEELS

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Acta Metallurgica Sinica(English Letters) 2006年第4期19卷 271-278页

作者： L.q. Ma z.Y. Liu S.H. Jiao X.q. Yuan D. Wu The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110004 China Institute of Research and Development Baosteel Co. Ltd Shanghai 201900 China

By using isothermal double hit compression tests and applying the 2% offset method, a new model was developed to predict the microstructural evolution of Nb-bearing steels at temperatures above and below the start temperature of strain-induced precipitation （Tp）. The Tp was developed as a function of true strain, initial austenite grain size and the Nb content. The activation energy of static recrystallization （qrex） was expressed as a function of the content of different alloy elements. It was found that Nb played the most important role in increasing the value of qrex, The microstructural observations and measurements confirmed the validity of the model developed in the present investigation.

关键词： Nb-bearing steel static recrystallization Tp (start temperature of strain-induced precipitation) activation energy

Prediction of effective diffusivity of porous media using deep learning method based on sample structure information self-amplification

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能源与人工智能(英文) 2020年第2期2卷 148-156页

作者： H.wang Y.Yin X.Y.Hui J.q.Bai z.g.qu School of Aeronautics Northwestern Polytechnical UniversityXi’anShaanxi 710072China MOE Key Laboratory of Thermo-Fluid Science and Engineering School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’anShaanxi 710049China

Effective diffusivity is one of the basic transport coefficients used to describe the mass transport capability of a porous *** this study,a deep learning method based on a convolutional neural network(CNN)with sam-ple structure information self-amplification is proposed to predict the effective diffusivity of a porous medium,which is considerably influenced by the morphological and topological parameters of the porous *** this method,the geometric structures of three-dimensional(3D)porous media are reproduced via a stochastic reconstruction *** of the effective diffusivities of the reconstructed porous media were first estab-lished by the pore-scale lattice Boltzmann method(LBM)simulation.A large number of geometric structures of 3D porous media are obtained using the proposed sample structure information self-amplification *** 3D geometric structure information and corresponding effective diffusivities are directionally applied to a CNN for training and *** effective diffusivities of media with porosities ranging from 0.48 to 0.58 are employed as training datasets,and the effective diffusivities of media with a broader porosity range of 0.39 to 0.79 are predicted by *** CNN model can achieve a fast and accurate prediction of the effective *** relative error between the CNN and LBM is 0.026%–8.95%with porosities ranging from 0.39 to *** a typical case with a porosity of 0.5,the computation time required by the CNN model is only 3×10^(−4) h,while the computation time for the same case is 16.96 h using the *** findings indicate that the proposed deep learning method has a powerful learning ability;it is time-saving,provides accurate predic-tions,and can serve as a promising and powerful tool to predict the transport coefficients of complex porous media.

关键词： Porous media Effective diffusivity Machine learning Convolutional neural network Lattice Boltzmann method