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Synergistic Effects in CNTs-PdAu/Pt Trimetallic Nanoparticles with High Electrocatalytic Activity and Stability

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Nano-Micro Letters 2017年第4期9卷 129-138页

作者： Xin-Lei Cai chang-Hai Liu Jie Liu Ying Lu ya-Nan Zhong Kai-Qi Nie Jian-Long xu xu Gao xu-Hui Sun Sui-Dong Wang Institute of Functional Nano and Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices Soochow University School of Materials Science and Engineering Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering Changzhou University

We present a straightforward physical approach for synthesizing multiwalled carbon nanotubes(CNTs)-Pd Au/Pt trimetallic nanoparticles(NPs), which allows predesign and control of the metal compositional ratio by simply adjusting the sputtering targets and conditions. The small-sized CNTs-Pd Au/Pt NPs(~3 nm, Pd/Au/Pt ratio of 3:1:2) act as nanocatalysts for the methanol oxidationreaction(MOR), showing excellent performance with electrocatalytic peak current of 4.4 A mg^(-1) Pt and high stability over 7000 s. The electrocatalytic activity and stability of the Pd Au/Pt trimetallic NPs are much superior to those of the corresponding Pd/Pt and Au/Pt bimetallic NPs,as well as a commercial Pt/C catalyst. Systematic investigation of the microscopic, crystalline, and electronic structure of the Pd Au/Pt NPs reveals alloying and charge redistribution in the Pd Au/Pt NPs, which are responsible for the promotion of the electrocatalytic performance.

关键词： CNTs PdAu/Pt Trimetallic nanoparticles Methanol oxidation reaction Electrocatalytic activity Synergistic effects

New Time Dependent Pretreat Models Based on Total Variational Image Restoration

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Acta Mathematicae Applicatae Sinica 2011年第1期27卷 129-140页

作者： Jing xu Qian-shun chang School of Statistics and Mathematics Zhejiang Gongshang University Hangzhou 310018 China Division of Mathematical Sciences School of Physical and Mathematical Sciences Nanyang TechnologicalUniversity 50 Nanyang Avenue Singapore 639798 Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 110190 China

In this paper, we propose new pretreat models for total variation （TV） minimization problems in image deblurring and denoising. Specially, blur operator is considered as useful information in restoration. New models in form is equivalent to pretreat the initial value by image blur operator. We successfully get a new （L. Rudin, S. Osher, and E. Fatemi） ROF model, a new level set motion model and a new anisotropic diffusion model respectively. Numerical experiments demonstrate that, under the same stopping rule, the proposed methods significantly accelerate the convergence of the toothed, save computation time and get the same restored effect.

关键词： Total variation image restoration level set motion anisotropic diffusion PSNR

Influence of electron density,temperature and decay energy onβ^(-)decay rates in a stellar environment

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Chinese Physics C 2022年第5期46卷 159-164页

作者： Shuo Liu chang xu School of Physics Nanjing UniversityNanjing 210093China

In this paper,the β^(−)decay rates in the magnetic field of a neutron star are investigated under different conditions of electron density,temperature,and decay *** considering the influence of magnetic field on the electron spectrum,we improve the Takahashi-Yokoi model and perform the calculations of β^(−)decay rates for the nickel(Ni)isotopes,which are the typical neutron-rich nuclei participating in the rapid neutron-capture process(r-process).It is found that the β^(−)decay rates are increased significantly in the extremely strong magnetic field(B>10^(15)G).Furthermore,we find oscillation of β^(−)decay rates with the increase of magnetic field strength,implying that the magnitude of β^(−)decay rates is closely related to not only the decay energy but also the environmental electron *** contrast,the impact of temperature on the β^(−)decay rates is found to be negligible in the range of 10^(7)K

关键词： beta decay neutron star magnetic field

A Robust Algorithm for Blind Total Variation Restoration

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Acta Mathematicae Applicatae Sinica 2008年第4期24卷 681-690页

作者： Jing xu Qian-shun chang School of Statistics and Mathematics Zhejiang Gongshang University Hangzhou 310018 China Academy of Mathematics and Systems Science Chinese Academy of Sciences Deijing 100190 China

Image restoration is a fundamental problem in image processing. Blind image restoration has a great value in its practical application. However, it is not an easy problem to solve due to its complexity and difficulty. In this paper, we combine our robust algorithm for known blur operator with an alternating minimization implicit iterative scheme to deal with blind deconvolution problem, recover the image and identify the point spread function（PSF）. The only assumption needed is satisfy the practical physical sense. Numerical experiments demonstrate that this minimization algorithm is efficient and robust over a wide range of PSF and have almost the same results compared with known PSF algorithm.

关键词： Blind deconvolution total variation algebraic multigrid method Krylov acceleration

Experimental study on surface integrity refactoring changes of Ti-17 under milling-ultrasonic rolling composite process

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Advances in Manufacturing 2023年第3期11卷 492-508页

作者： Zheng Zhou chang-Feng yao Liang Tan ya Zhang Yi Fan Key Laboratory of High Performance Manufacturing for Aero Engine Ministry of Industry and Information TechnologySchool of Mechanical EngineeringNorthwestern Polytechnical UniversityXi'an 710072People's Republic of China Engineering Research Center of Advanced Manufacturing Technology for Aero Engine Ministry of EducationSchool of Mechanical EngineeringNorthwestern Polytechnical UniversityXi'an 710072People's Republic of China

Ultrasonic rolling is an advanced non-cutting surface strengthening method that combines traditional rolling with ultrasonic *** this research,the experiment of orthogonal end milling-ultrasonic rolling composite process has been carried *** surface integrity refactoring changes and its mechanism of Ti-17 titanium alloy during the milling-ultrasonic rolling composite process has been studied and analyzed by the test and analysis of the surface geometric characteristics,residual stress,microhardness and microstructure before and after ultrasonic *** residual stress and microhardness gradient distribution were characterized by cosine decay function and exponential decay *** indicators of surface integrity were significantly improved after ultrasonic *** study demonstrates that the reduction effect of the surface roughness by ultrasonic rolling process is inversely proportional to the initial surface roughness *** ultrasonic rolling can only change the distribution form of the surface topography when the initial surface roughness is *** addition,the improvement effect of ultrasonic rolling on surface compressive residual stress and microhardness decreased with the increase of initial milled surface roughness and surface compressive residual stress due to the factors such as energy absorption efficiency and mechanical properties changes of surface materials.A better ultrasonic rolled surface can be obtained by controlling the roughness and residual compressive stress of the initial milling surface to a small level.

关键词： Ti-17 End milling Ultrasonic rolling Surface integrity Refactoring changes

Bending fatigue behavior of thin Zr_(61)Ti_(2)Cu_(25)Al_(12)bulk metallic glass beams for compliant mechanisms application

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Journal of Materials Science & Technology 2021年第30期89卷 1-15页

作者： Diao-Feng Li ya-Long yang Yong Shen Jian xu Institute of Metal Research Chinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China

In this work,bending fatigue behavior of thinner Zr_(61)Ti_(2)Cu_(25)Al_(12)(ZT1)BMG beams with thicknesses of 500μm and 100μm were investigated with three-point bending(3PB),to evaluate the reliability and safety of this potentially material used in compliant mechanisms under cyclic bending *** endurance limits(FELs)of ZT1 beams with thicknesses of 500μm and 100μm were determined to be 470 MPa,and~0.3 of its tensile *** life and FEL of ZT1 beams in bending are substantially independent of the beam thickness,in the scale from 500μm down to 100μ*** cracks of all ZT1 beams initiated at the extrinsic microvoids,either indirectly derived from surface scratches during mechanical polishing or originated from as-cast ***,fatigue crack propagation behavior is highly related to the magnitude of cyclic stress *** interrupted fatigue tests,larger proportion about 60-70%of fatigue life was spent on crack propagation under high stress level,while crack initiation occupied larger proportion about 80-85%under low stress *** medium stress level of about 590 MPa almost shared the crack-initiation life and crack-propagation *** addition,there are two crack deflection mechanisms during cracks steady propagation *** mechanism is crack deflection along the interacted shear bands ahead of crack-tip,the other one is crack"jump"from one shear band to another shear band at a certain *** two mechanisms alternate dominate the crack propagation process,generating typical staircase-like crack propagation *** endurance limits of ZT1 beams in the form of either stress amplitude or strain amplitude are superior to traditional candidate materials in the field of compliant mechanisms,showing that the better reliability and larger deflection deformation can be achieved for flexible members made by ZT1 BMG even under cyclic loading.

关键词： Metallic glasses Bending fatigue Crack initiation Crack propagation Compliant mechanisms

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供应链韧性研究进展及其测度方法研究

南宁师范大学学报（自然科学版） 2025年第1期42卷 48-58页

作者：马小雅徐浩彭俊豪南宁师范大学物流管理与工程学院广西南宁530100

通过文献计量和知识图谱方法,以“供应链韧性”为主题,分别从Web of Science和CNKI数据库中筛选出相关度较高的期刊文献,以“供应链韧性”测度为主题,从Web of Science数据库中筛选相关度较高的期刊文献。通过分析2010年以来国内外相关... 详细信息

通过文献计量和知识图谱方法,以“供应链韧性”为主题,分别从Web of Science和CNKI数据库中筛选出相关度较高的期刊文献,以“供应链韧性”测度为主题,从Web of Science数据库中筛选相关度较高的期刊文献。通过分析2010年以来国内外相关研究,探讨供应链韧性的热点问题、核心领域以及测度方法。研究发现:供应链韧性的热点问题主要聚焦供应链韧性的特性、测度方法、评价指标和影响因素,供应链韧性研究的核心领域则在供应链韧性特性研究、供应链韧性的优化设计以及供应链风险管理;供应链韧性测度的研究热点聚焦供应链韧性测度方法、指标体系、影响因素和供应链特性方面;供应链韧性及其测度的研究均呈现明显的时期特征。通过对测度方法的深入研究分析发现:供应链韧性测度方法包括定性分析、定量分析和综合评价分析,常用的综合评价法涵盖主观和客观权重法,旨在全面评估供应链的抵抗、恢复和适应能力。最后从供应链韧性理论深化和整合方向、供应链韧性测度指标体系构建和方法创新等方面对未来的研究方向进行探讨,以期对后续研究提供一定的指导。

关键词：供应链韧性测度方法评价指标影响因素文献计量知识图谱

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Effects of Anomalous Tensor Couplings in B_(s)^(0)-(B-)_(s)^(0) Mixing

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Chinese Physics Letters 2012年第3期29卷 67-70页

作者： chang Qin HAN Lin yaNG ya-Dong Institute of Particle Physics Huazhong Normal UniversityWuhan 430079 Department of Physics Henan Normal UniversityXinxiangHenan 453007 Key Laboratory of Quark&Lepton Physics(Ministry of Education) Huazhong Normal UniversityWuhan 430079

Motivated by the recently observed anomalous large dimuon charge asymmetry in neutral B decays,we study the effects of the anomalous tensor couplings to pursue a possible *** the constraints from the observablesφ_(s)^(J/(φ)(φ,f0),a_(sl)^(s)andΔM_(s),the new physics parameter spaces are severely *** find that the contributions induced by the color-singlet or the color-octet tensor operators are helpful to moderate the anomaly in BOs-(B-)***,the observable aSsl could be enhanced by about two orders of magnitude by the contributionsof color-singlet or color-octet tensor operators with their respective nontrivial new weak phaseφT_(1)=41°±35°orφs=-47°±33°and relevant strength parameters|gT1|=(2.89±1.40)×10^(-2) or|gT8|=(0.79±0.34)×10^(-2).However,due to the fact that the NP contributions are severely suppressed by the recent LHCb measurement forφJ/φ(φ,f0)s,our theoretical result of aSsl is still much smaller than the central value of the experimental data.

关键词： solution tensor operators

Protective role of hydrogen-rich water on aspirin-induced gastric mucosal damage in rats

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World Journal of Gastroenterology 2014年第6期20卷 1614-1622页

作者： Jing-yao Zhang Qi-Fei Wu Yong Wan Si-Dong Song Jia xu Xin-Sen xu Hu-Lin chang Ming-Hui Tai ya-Feng Dong chang Liu Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong University Health Science Center Department of Thoracic Surgery The First Affiliated Hospital of Xi’an Jiaotong University Health Science Center Department of Obstetrics and Gynecology University of Kansas School of Medicine

AIM: To investigate the role of the hydrogen-rich water (HRW) in the prevention of aspirin-induced gastric mucosal injury in rats.

关键词： Hydrogen Aspirin Gastric lesion Oxidative stress Cytokines Cyclooxygenase 2