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Research on deposition rate of TiZrV/Pd film by DC magnetron sputtering method

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Nuclear Science and Techniques 2017年第4期28卷 44-50页

作者： Jie wang Bo zhang Yan-Hui Xu yong wang National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei 230029 China

An accelerator storage ring needs clean ultrahigh vacuum.A TiZrV non-evaporable getter(NEG) film deposited on interior walls of the chamber can realize distributed pumping,effective vacuum improvement and reduced longitudinal pressure *** accumulation of pollutants such as N_2 and O_2 will decrease the adsorption ability of the NEG,leading to a reduction of NEG ***,an NEG thin film coated with a layer of Pd,which has high diffusion rate and absorption ability for H_2,can extend the service life of NEG and improve the pumping rate of H_2 as *** this paper,with argon as discharge gas,a magnetron sputtering method is adopted to prepare TiZrV-Pd films in a long straight *** SEM measurement,deposition rates of TiZrV-Pd films are analyzed under different deposition parameters,such as magnetic field strength,gas flow rate,discharge current,discharge voltage and working *** comparing the experimental results with the simulation results based on Sigmund's theory,the Pd deposition rate C can be estimated by the sputtered depth.

关键词： TiZrV-Pd Deposition rates Magnetron sputtering method Non-evaporable getter

Modulation of active Cr(III) complexes by bath preparation to adjust Cr(III) electrodeposition

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International Journal of Minerals,Metallurgy and Materials 2013年第9期20卷 902-908页

作者： Lei Li Zhi wang Ming-yong wang Yi zhang National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Institute of Process Engineering Chinese Academy of Sciences College of Chemistry and Chemical Engineering University of Chinese Academy of Sciences

The preparation process of the Cr（III） bath was studied based on a perspective of accelerating the formation of active Cr（III） complexes. The results of ultraviolet-visible absorption spectroscopy （UV-Vis） and electrodeposition showed that active Cr（III） complexes in the bath prepared at room temperature in several days were rare for depositing chromium. The increase of heating temperature, time, and pH value during the bath preparation promoted the formation of active Cr（III） complexes. The chromium deposition rate increased with the concentration of active Cr（III） complexes increasing. Increasing the heating temperature from 60 to 96℃, the chromium deposition rate increased from 0.40 to 0.71μm/min. When the concentration of active Cr（III） complexes increased, the grain size of Cr coatings increased, and the carbon content of the coating decreased. It is deduced that Cr（H20）4（OH）L2＋（L is an organic ligand, and its valence is omitted） is a primary active Cr（III） complex.

关键词： chromium complexes electrodeposition complexation coatings grain size

SUB-OPTIMAL CONVERGENCE OF DISCONTINUOUS GALERKIN METHODS WITH CENTRAL FLUXES FOR LINEAR HYPERBOLIC EQUATIONS WITH EVEN DEGREE POLYNOMIAL APPROXIMATIONS

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Journal of Computational Mathematics 2021年第4期39卷 518-537页

作者： yong Liu Chi-wang Shu Mengping zhang School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026China Division of Applied Mathematics Brown UniversityProvidenceRI 02912USA

In this paper,we theoretically and numerically verify that the discontinuous Galerkin(DG)methods with central fluxes for linear hyperbolic equations on non-uniform meshes have sub-optimal convergence properties when measured in the L^(2)-norm for even degree polynomial *** uniform meshes,the optimal error estimates are provided for arbitrary number of cells in one and multi-dimensions,improving previous *** theoretical findings are found to be sharp and consistent with numerical results.

关键词： Discontinuous Galerkin method Central flux Sub-optimal convergence rates

Theory and application of equivalent transformation relationships between plane wave and spherical wave

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Earthquake Engineering and Engineering Vibration 2017年第4期16卷 773-782页

作者： wang Yao Yang Zailin zhang Jianwei Yang yong College of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin 150001China

Based on the governing equations and the equivalent models, we propose an equivalent transformation relationships between a plane wave in a one-dimensional medium and a spherical wave in globular geometry with radially inhomogeneous properties. These equivalent relationships can help us to obtain the analytical solutions of the elastodynamic issues in an inhomogeneous medium. The physical essence of the presented equivalent transformations is the equivalent relationships between the geometry and the material properties. It indicates that the spherical wave problem in globular geometry can be transformed into the plane wave problem in the bar with variable property fields, and its inverse transformation is valid as well. Four different examples of wave motion problems in the inhomogeneous media are solved based on the presented equivalent relationships. We obtain two basic analytical solution forms in Examples I and II, investigate the reflection behavior of inhomogeneous half-space in Example III, and exhibit a special inhomogeneity in Example IV, which can keep the traveling spherical wave in constant amplitude. This study implies that our idea makes solving the associated problem easier.

关键词： elastodynamic issue equivalent transformation relationship governing equation inhomogeneous medium

Aging and rejuvenation during high-temperature deformation in a metallic glass

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Science China(Physics,Mechanics & Astronomy) 2022年第10期65卷 93-100页

作者： Langting zhang Yunjiang wang yong Yang Jichao Qiao School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical University(NPU)Xi’an 710072China State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China Department of Mechanical Engineering College of EngineeringCity University of Hong KongHong Kong 999077China Department of Materials Science and Engineering College of EngineeringCity University of Hong KongHong Kong 999077China Innovation Center NPU-ChongqingChongqing 401135China

High-temperature deformation has been demonstrated as an effective measure to rejuvenate and optimize the mechanical properties of metallic glasses(MGs).Clarifying the competition between aging and rejuvenation during high-temperature deformation is helpful in rejuvenating MGs *** of aging and rejuvenation in a La_(30)Ce_(30)Ni_(10)Al_(20)Co_(10)MG were investigated via high-temperature deformation and mechanical *** coupling of thermal history,aging,and mechanical disordering determines the transient deformation and the structural state of *** stress overshoot and anelastic deformation induce structural rejuvenation,increasing the concentration of defects and erasing thermal ***,the eventually steady-state condition is dependent on ambient temperature and strain rate instead of the initial ***,the one-to-one relationship between defect concentration and strain rate clarifies the structural nature of rejuvenation in amorphous *** a relationship also contributes toward a comprehensive understanding of the structural rejuvenation behavior in amorphous materials.

关键词： metallic glass aging rejuvenation homogenous flow free volume

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3D-structured carbon nanotube fibers as ultra-robust fabrics for adaptive electromagnetic shielding

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Nano Research 2024年第9期17卷 8521-8530页

作者： Dongping Li ping wang Yuanyuan Li Zhenzhong yong Kunjie Wu Yan zhang Jin wang Dongmei Hu Key Laboratory of Multifunctional and Smart Systems Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China College of Textile and Clothing Engineering of Soochow University Suzhou 215021China

Wireless communication technology is indispensable in our daily lives,but it also results in serious electromagnetic radiation ***,developing smart electromagnetic interference shielding materials with adjustable electromagnetic wave(EMW)responses holds significant promise for future electromagnetic shielding *** this study,we propose an electromagnetic shielding switch(ESS)characterized by tunable electromagnetic shielding performance achieved by fabricating a three-dimensional(3D)carbon nanotube-based spacer fabric(CNT-SF)and modifying CNT-SF with chemical vapor deposition(CCNT-SF).The CCNT-SF displays direction-dependent electrical conductivity by manipulating the warp and weft density,measuring 128 S/m transversely and 447 S/m *** characteristic allows the CCNT-SF to transmit or shield EMW by adjusting the angle of EMW incidence through fabric rotation,resulting in anisotropic electromagnetic shielding performance(33 dB transversely and 87 dB vertically).This feature enables switchable shielding with an on/off ratio of ***,the unique 3D structure confers excellent mechanical properties on the fabric,with compressive strength reaching 120 *** a flexible,lightweight,and mechanically robust ESS,the CCNT-SF holds promising prospects for mitigating the challenges of increasingly severe and intricate electromagnetic environments.

关键词： carbon nanotube spacer fabric electromagnetic shielding impact resistance joule heating electromagnetic shielding switch

In-situ Tension of Dendrite-Reinforced Zr-based Metallic-GlassMatrix Composites

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Acta Metallurgica Sinica(English Letters) 2014年第4期27卷 621-626页

作者： Huijun Yang Junwei Qiao Song wang yong zhang Research Institute of Surface Engineering Taiyuan University of Technology College of Materials Science and Engineering Taiyuan University of Technology State Key Laboratory of Advanced Metals and Materials University of Science and Technology Beijing

The evolution of shear bands in the glassy matrix composites was observed and analyzed during in-situ *** on the simple calculation,the temperature rise within the shear bands is sufficient to cause the formation of viscous shearing layer,resulting in the early ***-based metallic-glass-matrix composites（labeled as DH1 and DH2） exhibit improved tensile ductility rather than brittle failure,since the existence of secondary ductile dendrites promotes the impedance of prompt propagation of shear bands,evidenced by the multiplication of shear bands.

关键词： Amorphous alloy Deformation behavior Shear bands Notch

A Novel Metal-organic Framework Using Heterometallic Tetranuclear Cluster as Secondary Building Block and Isophthalic Acid as Ligand

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Chemical Research in Chinese Universities 2016年第5期32卷 709-712页

作者： BAI Helong zhang Daojun zhang Renchun wang Junjie ZENG Shuangli FAN yong XU Jianing zhang ping College of Chemistry Jilin University Changchun 130012 P. R. China College of Chemistry and Chemical Engineering Anyang Normal University Anyang 455002 P. R. China

A novel heterometallic-organic framework（HMOF）, namely [ZnBa（1,3-BDC）2（DMA）2],（I）（DMA=N,N- dimethylacetamide）, was synthesized by means of solvothermal method from isophthalic acid（1,3-BDC） ligand and relevant metal salts as raw materials. The single-crystal X-ray diffraction analysis result demonstrates that compound 1 is a three-dimensional（3D） framework including heterometallic tetranuclear [Zn2Ba2（COO）s] clusters as building subunits, which could be simplified into an eight-connected body-centered cubic（bcu） topological net. At room tem- perature, compound l displays strong blue luminescence in solid state. Furthermore, the quantum yield and lumines- cent lifetime of compound 1 were also measured.

关键词： Barium Isophthalic acid Solvothermal Luminescence property Heterometallic-organic framework

Multi-objective optimization and evaluation of supercritical CO_(2) Brayton cycle for nuclear power generation

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Nuclear Science and Techniques 2024年第2期35卷 183-209页

作者： Guo-Peng Yu yong-Feng Cheng Na zhang ping-Jian Ming Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China School of Civil Engineering and Architecture East China Jiaotong UniversityNanchang 330013China

The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle *** models of four Brayton cycle layouts are developed in this study for different reactors to reduce the cost and increase the thermohydraulic performance of nuclear power generation to promote the commercialization of nuclear *** analysis,multi-objective optimizations,and four decision-making methods are applied to obtain each Brayton scheme’s optimal thermohydraulic and economic *** show that for the same design thermal power scale of reactors,the higher the core’s exit temperature,the better the Brayton cycle’s thermo-economic *** the four-cycle layouts,the recompression cycle(RC)has the best overall performance,followed by the simple recuperation cycle(SR)and the intercooling cycle(IC),and the worst is the reheating cycle(RH).However,RH has the lowest total cost of investment(C_(tot))of$1619.85 million,and IC has the lowest levelized cost of energy(LCOE)of 0.012$/(kWh).The nuclear Brayton cycle system’s overall performance has been improved due to *** performance of the molten salt reactor combined with the intercooling cycle(MSR-IC)scheme has the greatest improvement,with the net output power(W_(net)),thermal efficiencyη_(t),and exergy efficiency(η_(e))improved by 8.58%,8.58%,and 11.21%,*** performance of the lead-cooled fast reactor combined with the simple recuperation cycle scheme was optimized to increase C_(tot) by 27.78%.In comparison,the internal rate of return(IRR)increased by only 7.8%,which is not friendly to investors with limited *** the nuclear Brayton cycle,the molten salt reactor combined with the recompression cycle scheme should receive priority,and the gas-cooled fast reactor combined with the reheating cycle scheme should be considered carefully.

关键词： Supercritical CO_(2)Brayton cycle Nuclear power generation Thermo-economic analysis Multi-objective optimization Decision-making methods