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Highly-efficient CoRuO_(x)nanocatalysts for acidic oxygen evolution:The merit of optimum ordering degree of carbon nanotube support

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Particuology 2024年第7期90卷 470-477页

作者： Wenwen Li Yanni Wang Zhenzhen Zhao Meiqi liu Qing Liang Yuhua liu fuxi liu Zhou Jiang Xu Zou Bingsen Zhang Wei Zhang Key Laboratory of Automobile Materials MOE School of Materials Science&EngineeringJilin Provincial International Cooperation Key Laboratory of High-Efficiency Clean Energy MaterialsElectron Microscopy CenterInternational Center of Future ScienceJilin UniversityChangchun 130012China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences110016ShenyangChina

Hydrogen production from proton exchange membrane water electrolysis is constrained by the sluggish kinetics of the anodic oxygen evolution ***_(2)has attracted considerable attention due to its low reaction overpotential,but its inferior stability remains a major ***,a strategy is proposed to enhance the catalytic activity and stability of CoRuOx nanoparticles by doping Co and regulating the ordering degree of carbon nanotubes(CNTs)by air *** was found that the CoRuOx@CNTs-300 catalyst exhibited the best catalytic activity and stability when the annealing temperature was 300°*** the current density of 10 mA cm−2,the overpotential of this catalyst was only 201 mV,which was nearly 100 mV lower than that of commercial RuO_(2)(300 mV).Surprisingly,there was no significant increase in the overpotential when tested at a current density of 10 mA cm−2 for 50 *** density functional theory calculations indicate that the high activity of the catalyst is due to the electronic coupling of CoRuOx nanoparticles and CNTs,and that the introduction of Co and CNTs improves the electronic structure and solvation energies of the Ru in the active site,dramatically increasing the structural stability.

关键词： Electrocatalysis RuO_(2) CNTs Oxygen evolution reaction

Optimizing high-coordination shell of Co-based single-atom catalysts for efficient ORR and zinc-air batteries

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Journal of Energy Chemistry 2024年第8期95卷 306-314,I0007页

作者： Yugang Qi Qing Liang Kexin Song Xinyan Zhou Meiqi liu Wenwen Li fuxi liu Zhou Jiang Xu Zou Zhongjun Chen Wei Zhang Weitao Zheng Key Laboratory of Automobile Materials MOE School of Materials Science&Engineering Electron Microscopy Centerand International Center of Future ScienceJilin Provincial International Cooperation Key Laboratory of High-Efficiency Clean Energy MaterialsJilin UniversityChangchun 130012JilinChina Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Atom-level modulation of the coordination environment for single-atom catalysts(SACs)is considered as an effective strategy for elevating the catalytic *** the MNxsite,breaking the symmetrical geometry and charge distribution by introducing relatively weak electronegative atoms into the first/second shell is an efficient way,but it remains challenging for elucidating the underlying mechanism of ***,a practical strategy was reported to rationally design single cobalt atoms coordinated with both phosphorus and nitrogen atoms in a hierarchically porous carbon derived from metal-organic frameworks.X-ray absorption spectrum reveals that atomically dispersed Co sites are coordinated with four N atoms in the first shell and varying numbers of P atoms in the second shell(denoted as Co-N/P-C).The prepared catalyst exhibits excellent oxygen reduction reaction(ORR)activity as well as zinc-air battery *** introduction of P atoms in the Co-SACs weakens the interaction between Co and N,significantly promoting the adsorption process of ^(*)OOH,resulting in the acceleration of reaction kinetics and reduction of thermodynamic barrier,responsible for the increased intrinsic *** discovery provides insights into an ultimate design of single-atom catalysts with adjustable electrocatalytic activities for efficient electrochemical energy conversion.

关键词： Electrocatalytic Oxygen reduction reaction Single atom catalyst Shell coordination optimization

Analytical Higher-Order Model for Flexible and Stretchable Sensors

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Chinese Journal of Mechanical Engineering 2015年第2期28卷 379-386页

作者： ZHANG Yongfang ZHU Hongbin liu Cheng liu Xu liu fuxi L Yanjun School of Printing and Packaging Engineering Xi'an University of Technology State Key Laboratory for Strength and Vibration of Mechanical Structures Xi'an Jiaotong University College of Engineering Michigan State University School of Mechanical and Precision Instrument Engineering Xi'an University of Technology School of Mechanical Engineering Xi'an Aeronautical University

The stretchable sensor wrapped around a foldable airfoil or embedded inside of it has great potential for use in the monitoring of the structural status of the foldable *** design methodology is important to the development of the stretchable sensor for status monitoring on the foldable *** to the requirement of mechanical flexibility of the sensor,the combined use of a layered flexible structural formation and a strain isolation layer is *** analytical higher-order model is proposed to predict the stresses of the strain-isolation layer based on the shear-lag model for the safe design of the flexible and stretchable *** normal stress and shear stress equations in the constructed structure of the sensors are obtained by the proposed *** stress distribution in the structure is investigated when bending load is applied to the *** numerical results show that the proposed model can predict the variation of normal stress and shear stress along the thickness of the strain-isolation（polydimethylsiloxane）layer *** results by the proposed model are in good agreement with the finite element method,in which the normal stress is variable while the shear stress is invariable along the thickness direction of strain-isolation *** high-order model is proposed to predict the stresses of the layered structure of the flexible and stretchable sensor for monitoring the status of the foldable airfoil.

关键词： flexible and stretchable sensors higher-order shear-lag model normal stress shear stress

Approximate Solution of Oil Film Load-carrying Capacity of Turbulent Journal Bearing with Couple Stress Flow

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 106-114页

作者： ZHANG Yongfang WU Peng GUO Bo L Yanjun liu fuxi YU Yingtian School of Printing and Packaging Engineering Xi'an University of Technology State Key Laboratory for Strength and Vibration of Mechanical Structures Xi'an Jiaotong University College of Engineering Michigan State University Xi'an Institute of Mechatronics Information Technology School of Mechanical and Precision Instrument Engineering Xi'an University of Technology Department of Civil Engineering University of California Los Angeles

The instability of the rotor dynamic system supported by oil journal bearing is encountered frequently, such as the half speed whirl of the rotor, which is caused by oil film lubricant with nonlinearity. Currently, more attention is paid to the physical characteristics of oil film due to an oil-lubricated journal bearing being the important supporting component of the bearing-rotor systems and its nonlinear nature. In order to analyze the lubrication characteristics of journal bearings efficiently and save computational c[~brts, an approximate solution of nonlinear oil film forces of a finite length turbulent journal bearing with couple stress flow is proposed based on Sommerfeld and Ocvirk numbers. Reynolds equation in lubrication of a finite length turbulent .journal bearing is solved based on multi-parametric principle. Load-carrying capacity of nonlinear oil film is obtained, and the results obtained by different methods are compared. The validation of the proposed method is verified, meanwhile, the relationships of load-carrying capacity versus eccentricity ratio and width-to-diameter ratio under turbulent and couple stress working conditions are analyzed. The numerical results show that both couple stress flow and eccentricity ratio have obvious influence on oil film pressure distribution, and the proposed method approximates the load-carrying capacity of turbulent journal bearings efficiently with various width-to-diameter ratios. This research proposes an approximate solution of oil film load-carrying capacity of turbulent journal bearings with different width-to-diameter ratios, whicb are suitable for high eccentricity ratios and heavy loads.

关键词： finite length turbulent journal bearing couple stress fluid multi-parametric principle

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教育发展中的某些盲点

教育发展研究 2005年第3期25卷 71-73页

作者：刘富喜湖南株洲市教育学会会长湖南省政府督学株洲313000

盲点之一:忽视人口动态对教育的影响联合国教科文组织1994年关于《基础教育、人口与发展》的报告指出:"人口是对一个社会的发展尤其是对教育体系造成冲击的基本因素.然而,这不是一个单向过程.发展和教育依次对人口以及对人口动态产生影... 详细信息

盲点之一:忽视人口动态对教育的影响联合国教科文组织1994年关于《基础教育、人口与发展》的报告指出:"人口是对一个社会的发展尤其是对教育体系造成冲击的基本因素.然而,这不是一个单向过程.发展和教育依次对人口以及对人口动态产生影响."在这里,姑且不探讨教育对人口的影响,而是把着眼点放在人口对教育的影响上.人口及人口动态是教育发展的决定因素之一.

关键词：教育发展人口动态教育资源中国人口规模

学前儿童的因果判断——对时空信息的利用(Ⅰ)

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心理科学通讯 1989年第1期12卷 3-8,66页

作者：方富熹方格刘范中国科学院心理研究所

本实验研究是作者以前三个实验①②的继续,实验中给儿童演示一个物体碰撞的因果系列事件,告知儿童有关的因果机制,要求儿童对两种可能的时间或空间信息作出选择性的归因判断.结果表明,在学前儿童中已迅速发展着一种依据因果系列事件的... 详细信息

本实验研究是作者以前三个实验①②的继续,实验中给儿童演示一个物体碰撞的因果系列事件,告知儿童有关的因果机制,要求儿童对两种可能的时间或空间信息作出选择性的归因判断.结果表明,在学前儿童中已迅速发展着一种依据因果系列事件的时序关系或空间距离关系作出因果判断的能力,在利用时空信息时,他们对时间信息更为敏感.

关键词：时间规则红球蓝球运动学前儿童运动表象因果判断近距离时空信息先行事件百分比

人工真皮联合自体瘢痕表皮移植修复大面积烧伤后期关节部位瘢痕畸形

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中国组织工程研究 2024年第10期28卷 1533-1539页

作者：付全有邢福席李林李勇刘继松蚌埠医学院附属蚌埠第三人民医院安徽省蚌埠市233000

背景:如何既为大面积深度烧伤患者瘢痕整形修复提供足够的皮源,又能避免术区创面瘢痕的再次增生,一直是烧伤与创面修复研究的重要课题。目的:观察人工真皮联合自体瘢痕表皮复合移植在大面积烧伤后瘢痕整复中的临床应用效果。方法:回顾... 详细信息

背景:如何既为大面积深度烧伤患者瘢痕整形修复提供足够的皮源,又能避免术区创面瘢痕的再次增生,一直是烧伤与创面修复研究的重要课题。目的:观察人工真皮联合自体瘢痕表皮复合移植在大面积烧伤后瘢痕整复中的临床应用效果。方法:回顾性分析2021年1月至2023年1月在蚌埠医学院附属蚌埠第三人民医院接受手术治疗的大面积烧伤后瘢痕增生、挛缩畸形患者的病历资料,共纳入73例,按照治疗方法分为3组:A组(n=21)接受人工真皮联合自体瘢痕表皮移植治疗;B组(n=27)接受功能部位瘢痕松解后移植自体瘢痕表皮治疗;C组(n=25)接受功能部位瘢痕松解后移植自体中厚皮治疗。记录3组患者受皮区皮片存活及感染情况,受皮区及供皮区创面愈合时间;通过温哥华瘢痕量表(VSS)、日常生活活动能力(ADL)评定3组患者受皮区、供皮区瘢痕情况及受皮区功能恢复情况。结果与结论:①B组患者皮片感染率低于A、C组(P<0.05),皮片存活优级率高于A、C组(P<0.05);②A组患者受皮区创面完全愈合时间长于B、C组(P<0.05),C组患者受皮区创面完全愈合时间长于B组(P<0.05);C组患者供皮区完全愈合时间长于A、B组(P<0.05);③B组患者术后12个月受皮区温哥华瘢痕量表评分高于A、C组(P<0.05),C组患者术后6,12个月供皮区温哥华瘢痕量表评分高于A、B组(P<0.05);A、C组患者术后12个月日常生活活动能力量表评估优级高于B组(P<0.05);④结果显示,应用人工真皮与自体瘢痕表皮复合移植治疗大面积烧伤后瘢痕挛缩,既能达到与中厚皮移植同样的效果,又能避免供皮区术后瘢痕的再次增生,可缩短供皮区创面愈合时间,相较于单纯移植瘢痕表皮治疗有明显优势。

关键词：人工真皮瘢痕表皮大面积烧伤瘢痕增生挛缩畸形整形皮片移植

含双时滞轴向槽动压气体轴承–非线性转子系统的运动分析

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中国电机工程学报 2014年第35期34卷 6346-6354页

作者：张永芳张帅叶鹏刘成刘付喜吕延军西安理工大学陕西省西安市710048 西安工业大学教务处陕西省西安市710032

针对高速气体轴承-转子系统在主动控制过程中无法避免的时滞现象,建立了含有双时滞控制的三轴向槽动压气体轴承-转子系统的动力学模型。运用微分变换法求解动压气体润滑的Reynolds方程,得到了非线性气膜压力分布。基于精细积分法,构造... 详细信息

针对高速气体轴承-转子系统在主动控制过程中无法避免的时滞现象,建立了含有双时滞控制的三轴向槽动压气体轴承-转子系统的动力学模型。运用微分变换法求解动压气体润滑的Reynolds方程,得到了非线性气膜压力分布。基于精细积分法,构造了时滞非线性轴承-转子系统动力响应的求解方法。针对含有双时滞控制的气体轴承-转子系统,运用轨迹图、时间历程图等研究了系统的非线性响应,分析了时滞量和反馈控制增益对系统响应的影响。数值结果表明,当选取的反馈控制增益与气体轴承-转子系统的时滞量相匹配时,时滞系统的振动幅值会变小,运动将更加稳定,达到了较好的控制效果。

关键词：非线性转子系统轴向槽动压气体轴承时滞微分变换法精细积分法稳定性

基于分数阶导数的黏弹性悬架减振模型及其数值方法

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振动与冲击 2016年第16期35卷 123-129页

作者：李占龙孙大刚宋勇刘付喜赵树萍西安理工大学机械与精密仪器学院西安710028 太原科技大学机械工程学院太原030024

为了准确掌握黏弹性悬架的动态响应,针对传统整数阶减振模型的不足,引入分数阶导数原理,构建了黏弹性材料FKV本构模型,建立了考虑几何参数的黏弹性悬架分数阶减振模型,利用Grumwald-Letnikov定义将模型中分数阶导数离散化,并转化为状态... 详细信息

为了准确掌握黏弹性悬架的动态响应,针对传统整数阶减振模型的不足,引入分数阶导数原理,构建了黏弹性材料FKV本构模型,建立了考虑几何参数的黏弹性悬架分数阶减振模型,利用Grumwald-Letnikov定义将模型中分数阶导数离散化,并转化为状态方程形式,依据矩阵函数理论推导出模型的数值解。以某型安装黏弹性悬架的履带车辆参数为例,分别建立了悬架的动态接触有限元模型和分数阶减振模型,获得了在翻越障碍工况下两种模型响应的对比解。结果表明:分数阶减振模型体现了黏弹性悬架响应具有全局相关性和记忆性,且历史作用渐近加强;黏弹性悬架有较好的缓冲减振性能;分数阶减振模型解与有限元方法计算结果有较好的一致性。旨为下一步的实车试验和实际应用提供理论参考。

关键词：分数阶导数黏弹性悬架减振模型数值方法