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Current-carrying friction in carbon coated ball bearing

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Friction 2023年第11期11卷 2008-2020页

作者： Peidong xue Cheng CHEN xue FAN Dongfeng DIAO Institute of Nanosurface Science and Engineering(INSE) Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics EngineeringShenzhen UniversityShenzhen 518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China

In this work,we proposed a method for coating the whole surfaces of bearing balls uniformly by carbon film with a rotatable ball *** studied the carbon/carbon friction with a self-designed currentcarrying ball bearing friction test system.A notable and instant friction force drop of 28%and significant carbon film wear alleviation were found when currents were *** using TEM-,SEM-,and EDS-analysis,special carbon stacks with a mixture of large wear particles and oxide were found in the wear areas under current applied *** elucidated the current-carrying friction mechanisms as follows:(1)wear particles formation;(2)wear particles charged by tribomicroplasma;(3)formation of surface passivated carbon stacks under electric force;(4)sliding between passivated carbon *** work may facilitate the development of novel solid-lubricated ball bearings and lay some foundations for current-carrying rolling friction.

关键词： current-carrying friction carbon film ball bearing carbon stack

Multiple optimal solutions to a sort of nonlinear optimization problem

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Journal of Systems Engineering and Electronics 2007年第1期18卷 63-67页

作者： xue Shengjia Management School Jinan Univ. Guangzhou 510632 P. R. China

The optimization problem is considered in which the objective function is pseudolinear（both pseudoconvex and pseudoconcave） and the constraints are linear. The general expression for the optimal solutions to the problem is derived with the representation theorem of polyhedral sets, and the uniqueness condition of the optimal solution and the computational procedures to determine all optimal solutions （if the uniqueness condition is not satisfied ） are provided. Finally, an illustrative example is also given.

关键词： Pseudolinear optimization problem Polyhedral set Representation theorem Multiple optimal solutions Convex simplex method

Approach for Obtaining Material Mechanical Properties in Local Region of Structure Based on Accurate Analysis of Micro-indentation Test

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Chinese Journal of Mechanical Engineering 2021年第6期34卷 147-158页

作者： He xue Jinxuan He Jianlong Zhang Yuxuan xue School of Mechanical Engineering Xi’an University of Science and TechnologyXi’an710054China Xi’an Special Equipment Inspection Institute Xi’an710065China Department of Industrial and Manufacturing Systems Engineering The University of Hong KongHong Kong999077China

The hot or cold processing would induce the change and the inhomogeneous of the material mechanical properties in the local processing region of the structure,and it is difficult to obtain the specific mechanical properties in these regions by using the traditional material tensile *** accurately get actual material mechanical properties in the local region of structure,a micro-indentation test system incorporated by an electronic universal material test device has been *** indenter displacement sensor and a group of special micro-indenter assemblies are estab-lished.A numerical indentation inversion analysis method by using ABAQUS software is also proposed in this *** on the above test system and analysis platform,an approach to obtaining material mechanical properties in the local region of structures is proposed and *** ball indentation test is performed and combined with the energy method by using various changed mechanical properties of 316L austenitic stainless steel under differ-ent *** investigated results indicate that the material mechanical properties and the micro-indentation morphological changes have evidently *** with the tensile test results,the deviations of material mechanical parameters,such as hardness H,the hardening exponent n,the yield strength σy and others are within 5%obtained through the indentation test and the finite element *** provides an effective and convenient method for obtaining the actual material mechanical properties in the local processing region of the structure.

关键词： Structural integrity assessment Micro-indentation test Numerical testing inversion analysis Local material mechanical property

A Controlled Phase Gate with Nitrogen-Vacancy Centers in Nanocrystal Coupled to a Silica Microsphere Cavity

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Chinese Physics Letters 2010年第6期27卷 5-8页

作者： xue Peng Department of Physics Southeast University Nanjing 211189

We show how a controlled phase gate, induced by adiabatic passage of dark states, can be implemented with the nitrogen-vacancy defects in nanocrystal coupled to the optical whispering gallery mode in a silica microsphere cavity. The gate presented is robust to the fluctuations of the experimental parameters compared to the dynamical and geometric phases gates. The feasibility of this scheme is characterized by exact numerical simulations that incorporate various sources of experiment noise. The results demonstrate the practicality by way of current experimental technologies.

关键词： GATE array circuits NITROGEN POINT defects NANOCRYSTALS SILICA NUMERICAL analysis SIMULATION methods & models

College Education for Students From Needy Families

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The Journal of Human Rights 2004年第1期3卷 12-13页

作者： WANG jiaquan

Thousands of youngsters in China feel overjoyed when admitted to an institution of higher learning, after years of painstaking studies and highly competitive entrance examinations. But Lin xue from Dalian in northeast China’s Liaoning Province wept for days upon admission from the China Medical University in Shenyang, the provincial capital, in 2000. Although she longed to enter the university renowned in the field of medical science education, Lin decided, painfully, to hide the admission letter from her parents and give up the rare opportunity to change her destiny. "I was fully aware that my parents could by no means afford my tuition and living expenses in college," Lin recalls. Both of her farmer parents were in poor health: her

关键词： College Education for Students From Needy Families

超前钻孔直径对高应力巷道卸压及掏槽爆破效果影响研究

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华北理工大学学报（自然科学版） 2025年第1期47卷 53-61页

作者：黄斌胡学龙安徽理工大学安徽省煤矿安全采掘装备制造业创新中心安徽淮南232001 中国矿业大学煤炭精细勘探与智能开发全国重点实验室江苏徐州221116 安徽理工大学矿业工程学院安徽淮南232001

随着煤炭开采逐步向深部推进,巷道开挖过程中应力集中问题日益突显,亟需有效解决。本文采用Ansys/Ls-Dyna数值模拟软件,针对高应力环境下不同超前钻孔直径对巷道卸压效果及掏槽爆破效果的影响进行了系统研究。利用ImageJ图像处理软件对... 详细信息

随着煤炭开采逐步向深部推进,巷道开挖过程中应力集中问题日益突显,亟需有效解决。本文采用Ansys/Ls-Dyna数值模拟软件,针对高应力环境下不同超前钻孔直径对巷道卸压效果及掏槽爆破效果的影响进行了系统研究。利用ImageJ图像处理软件对巷道掏槽爆破损伤云图进行了详细分析。结果表明,随着超前钻孔直径的增加,钻孔孔底至岩石内部区域的有效应力逐渐降低,有效实现了卸压作用;随着超前钻孔直径的增大,掏槽爆破岩石块度逐渐减少,小块度占比显著增加,且在大直径钻孔爆破中岩石块度的分布更为均匀。研究成果对提升高应力巷道掏槽爆破效果具有重要指导意义。

关键词：高应力超前钻孔掏槽爆破数值模拟

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Dehydration, hydrolysis and oxidation of cerium chloride heptahydrate in air atmosphere

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Journal of Rare Earths 2017年第11期35卷 1156-1163页

作者： Shoufeng xue Wenyuan Wu xue Bian Yongfu Wu Metallurgy School of Northeastern University Shenyang 110819 PR China School of Energy and Environmental Engineering Inner Mongolia University of Science and Technology Baotou 014010 PR China

The thermal decomposition of CeCl3·7 H2O was studied from room temperature to 800 ℃. Analysis was performed by applying TG-DTA, XRD, FESEM, EDXS, and TG-MS technologies to investigate the thermal decomposition mechanism of CeCl3·7 H2O in air atmosphere. Multiple forms of hydrated cerium chloride compound were observed in the dehydration products. The CeCl3hydrolysis product was separated by a continuous centrifugation method and the phase composition was identified as CeO2,Ce(OH)3,and CeCl3·4 H2O by XRD analysis. The evolved gas composition was identified as CI2and HCI by TG-MS system. Based on the analysis of the experimental results, the mechanism of thermal decomposition of CeCl3·7 H2O was proposed with completion of the dehydration reaction at 224 ℃,the hydrolysis reaction at 170-480 ℃,and the oxidation reaction of CeCl3above 480 ℃.

关键词： CeCl_3 Hydrolysis Oxidation XRD MS

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新型混编支架的制备与径向支撑力学行为

中国组织工程研究 2025年第16期29卷 3440-3448页

作者：薛广明木合塔尔·克力木李洪新疆大学机械工程学院新疆维吾尔自治区乌鲁木齐市830047

背景:编织支架因良好的柔顺性被广泛应用于狭窄动脉的治疗,但在提供足够的径向支撑性能方面存在明显局限。目的:针对单一材料制成的编织支架存在径向支撑力不足的问题,采用不同力学参数的生物可降解材料混合编织支架,探究影响混编支架... 详细信息

背景:编织支架因良好的柔顺性被广泛应用于狭窄动脉的治疗,但在提供足够的径向支撑性能方面存在明显局限。目的:针对单一材料制成的编织支架存在径向支撑力不足的问题,采用不同力学参数的生物可降解材料混合编织支架,探究影响混编支架径向力学性能的影响因素。方法:在镁合金支架中引入铁合金纱线,采用有限元分析法对不同编织参数的混编支架进行参数化分析,通过与0.18 mm直径镁合金纱线制备的普通支架进行对比,评估其径向支撑力、径向回弹率和扩张不均匀性。结果与结论:①当铁合金纱线直径为0.18 mm和0.14 mm时,随着铁合金纱线数量的增多,混编支架的径向支撑力增加;此时,尽管直径0.14 mm铁合金纱线提供的径向支撑力小于同数量的0.18 mm铁合金纱线,但增加细铁合金纱线的数量可以达到与较粗铁合金纱线混编支架相媲美的径向支撑力。当铁合金纱丝直径为0.10 mm时,随着铁合金纱线数量的增加,混编支架的径向支撑力降低。②增大编织角度,混编支架的径向支撑力降低,但其径向回弹率和狗骨率得到了改善。通过降低编织角可以改善小直径铁合金纱线造成的支架径向支撑力不足。③结果显示,在镁合金支架中引入铁合金纱线,可以实现在不增加纱线直径的情况下精确地调整支架的径向力学性能,这不仅克服了单一材料支架的局限性,也为多材料支架的设计提供了新思路。

关键词：编织支架生物可降解材料镁合金铁合金支架结构径向支撑性能狗骨率有限元分析

Galerkin approximation with Legendre polynomials for a continuous-time nonlinear optimal control problem

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Frontiers of Information Technology & Electronic Engineering 2017年第10期18卷 1479-1487页

作者： xue-song CHEN School of Applied Mathematics Guangdong University of TechnologyGuangzhou 510006China

We investigate the use of an approximation method for obtaining near-optimal solutions to a kind of nonlinear continuous-time(CT) system. The approach derived from the Galerkin approximation is used to solve the generalized Hamilton-Jacobi-Bellman(GHJB) equations. The Galerkin approximation with Legendre polynomials(GALP) for GHJB equations has not been applied to nonlinear CT systems. The proposed GALP method solves the GHJB equations in CT systems on some well-defined region of attraction. The integrals that need to be computed are much fewer due to the orthogonal properties of Legendre polynomials, which is a significant advantage of this approach. The stabilization and convergence properties with regard to the iterative variable have been *** examples show that the update control laws converge to the optimal control for nonlinear CT systems.

关键词： Generalized Hamilton-Jacobi-Bellman equation Nonlinear optimal control Galerkin approximation Legendre polynomials