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Frontiers of Chemical Science and Engineering 2018年第3期12卷 473-480页

作者： shenghua ye Gaoren Li MOE Laboratory of Bioinorganic and Synthetic Chemistry KLGHEI of Environment and Energy Chemistry School of Chemistry and Chemical Engineering Sun Yat-sen University Guangzhou 510275 China

Abstract The polypyrrole（PPy）@NiCo hybrid nanotube arrays have been successfully fabricated as a high performance electrocatalyst for hydrogen evolution reaction （HER） in alkaline solution. The strong electronic interactions between PPy and NiCo alloy are confirmed by X-ray photoelectron spectroscopy and Raman spectra. Because these interations can remarkably reduce the apparent activation energy （Ea） for HER and enhance the turnover frequency of catalysts, the electrocatalytic performance of PPy@NiCo hybrid nanotube arrays are significantly improved. The electrochemical tests show that the PPy@NiCo hybrid catalysts exhibit a low overpotential of-186 mV at 10.0 mA·cm^-2 and a small tafel slope of 88.6 mV·deg^-1 for HER in the alkaline solution. The PPy@NiCo hybrid nanotubes also exhibit high catalytic activity and high stability for HER.

关键词： NiCo alloy polypyrrole hybrid nanotube electrocatalyst hydrogen evolution reaction

Editorial for the Special Issue on Precision Engineering

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Engineering 2018年第6期4卷 743-744页

作者： shenghua ye Fengzhou Fang State Key Laboratory of Precision Measuring Technology and Instruments Tianjin UniversityTianjin 300072China

Precision engineering has developed from its original literal meaning of“making things precisely”into a sub-discipline of electrical engineering,software engineering,electronics engineering,mechanical engineering,and optical engineering that is concerned with designing machines,fixtures,and other structures that have exceptionally high tolerances,are repeatable,and are stable over *** advanced research on precision engineering,the behavior of an experimental system remains fully predictable,even including micro/nanoscale ***/nano-scale phenomena introduce a wide spectrum of unknown fields and promising applications that have driven researchers to dedicate themselves to work in molecular electronics,biomedical applications,picosecond lasers,nanometric fabrication,and micro/nano devices.

关键词： Editorial Special Issue Precision Engineering

复杂岩溶地层大口径DRCP顶管施工试验研究

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人民长江 2024年第8期55卷 166-173页

作者：叶生华陆俊明攀王涛聂叙平南京水利科学研究院江苏南京210029 贵阳水资源开发投资有限公司贵州贵阳550081 河海大学水安全与水科学协同创新中心江苏南京210029 中铁隧道局集团有限公司广东广州511458

复杂岩溶地层中大口径顶进施工法用钢筋混凝土管(DRCP)顶进施工过程中的最大顶力值,是顶管施工中最关键的施工控制指标,决定了顶管施工的效率。为了研究复杂岩溶地层大口径DRCP顶进过程中的总顶力变化规律,建立了DRCP顶进过程力平衡模型... 详细信息

复杂岩溶地层中大口径顶进施工法用钢筋混凝土管(DRCP)顶进施工过程中的最大顶力值,是顶管施工中最关键的施工控制指标,决定了顶管施工的效率。为了研究复杂岩溶地层大口径DRCP顶进过程中的总顶力变化规律,建立了DRCP顶进过程力平衡模型,并基于贵阳市“汪家大井”水源应急工程的管道工程,开展了岩溶地层中DRCP顶进过程原位试验,对顶管施工过程中的顶管顶力进行实时监测和分析。结果表明:DRCP顶进过程主要分为切削力平衡阶段、顶力渐变平衡阶段和摩阻力平衡阶段;对于岩溶地区的燧石灰岩、灰岩和砂质页岩,采用泥浆减阻的DRCP的平均摩阻力fk分别为:6.06,5.81,3.78 kN/m^(2),在顶管设计和顶进施工的顶力控制中,可以将其乘以安全系数,作为类似顶管工程的取值参考;触变泥浆减阻DRCP在不同岩体顶进过程中的顶进阻力不同,岩石越坚硬,DRCP受到的平均切削力、平均摩阻力和综合摩擦系数越大。提出的复杂岩溶地层大口径DRCP顶力计算方法,对于明晰DRCP顶进施工控制指标,保障施工安全和进度具有重要意义。

关键词：复杂岩溶地层 DRCP管顶管施工最大顶力摩阻力

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Verticality Detection Algorithm Based on Local Image Sharpness Criterion

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Chinese Journal of Mechanical Engineering 2012年第1期25卷 173-178页

作者： ZHANG Jin WANG Zhong ye shenghua YANG Chun LI Lin State Key Laboratory of Precision Measuring Technology and Instruments Tianjin UniversityTianjin 300072China

In the high precision image measurement system, the verticality error between the axis of the shooting system and the measured object can bring error of the measurement result. The high demand of the system’s vertical degree is raised by measure system due to the demands of high precision and disposable full field imaging in the micro-parts imaging measurement. The existing method of optical axis verticality detection cannot meet the demand all. In order to achieve the high-precision adjustment of the system optical axis, the algorithm of detecting verticality based on regional image definition is proposed. First, the objected standard image is divided into fixed area. Then, the object plane is moved from the downside to the upside of the focus plane, meanwhile, recording the definition function values of each standard image region at each step, and fitting out the clearest positions of the regions. Finally, according to the inter-regional relations between the locations and the height difference of the each regional clearest position, the small angle between the optical axis and the measured surface can be calculated. The experiment is based on the given image of lithography template with the scale of 10 μm as move unit, and the results show that this method effective reduced the small angle between the system optical axis and the measured body in high-precision image measuring system, the evaluation accuracy is less than 0.1°, meeting the requirements in high-precision measurement. The proposed method of detecting verticality based on regional image definition can evaluate the verticality error between the axis of the shooting system and the measured object accurately, effectively and conveniently.

关键词： verticality detection image definition optical axis adjustment

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福建永泰庄寨时空分布特征及影响因素

福建史志 2024年第1期 25-38,72,91页

作者：叶胜华卢姗林榕陈顺和任维福建农林大学风景园林与艺术学院

现阶段永泰庄寨的保护开发存在独立性、分散性,不利于庄寨建筑的统筹协调。文章运用ArcGIS分析庄寨的时空分布格局,探究其影响因素,为庄寨的集中保护、联动开发与综合提升提供借鉴。

关键词：永泰庄寨空间分析影响因素 ArcGIS

A cerium-doped NASICON chemically coupled poly(vinylidene fluoride-hexafluoropropylene)-based polymer electrolyte for high-rate and high-voltage quasi-solid-state lithium metal batteries

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Journal of Energy Chemistry 2022年第10期31卷 311-321,I0007页

作者： Tao Huang Wei Xiong Xue ye Zhencheng Huang Yuqing Feng Jianneng Liang shenghua ye Jishou Piao Xinzhong Wang Yongliang Li Xiangzhong Ren Chao Chen Shaoluan Huang Xiaoping Ouyang Qianling Zhang Jianhong Liu Graphene Composite Research Center College of Chemistry and Environmental Engineering.Shenzhen UniversityShenzhen 518060GuangdongChina Institute of information Technology Shenzhen Institute of Information TechnologyShenzhen 518060.GuangdongChina henzhen Eigen-Equation Graphene Technology Co.Ltd Shenzhen 518060Guangdong.China School of Materials Science and Engineering Xiangtan UniversityXiangtan 41105HunanChina

The isolated inorganic particles within composite polymer electrolytes(CPEs) are not correlated to the Li^(+)transfer network,resulting in the polymer dominating the low ionic conductivity of ***,we developed novel quasi-solid-state CPEs of a Ce-doped Na super ion conductors(NASICON)Na_(1.3+x)Al_(0.3)Ce_(x)Ti_(1.7-x)(PO_(4))_(3)(NCATP) chemically coupled poly(vinylidene fluoride-hexafluoropropylene)(PVDF-HFP)/Li-bis(trifluoromethanes-ulfonyl)imide(LiTFSI) matrix.A strong interaction between Ce^(3+)from NCATP and TFSI-anion from the polymer matrix contributes to the fast Li+transportation at the *** PVDF-HFP/NCATP CPEs exhibit an ionic conductivity of 2.16 × 0^(-3) S cm^(-1) and a Li^(+) transference number of 0.88.A symmetric Li/Li cell with NCATP-integrated CPEs at 0.1 mA cm^(-2) presents outstanding cycling stability over 2000 h at 25℃.The quasi-solid-state Li metal batteries of Li/CPEs/LiFePO_(4) at 2 C after 400 cycles and Li/CPEs/LiCoO_(2) at 0.2 C after 120 cycles deliver capacities of 100 and 152 mAh g^(-1) at 25℃,respectively.

关键词： Quasi-solid-state batteries Composite polymer electrolytes High conductivity High-voltage cathode Oxygen vacancies

Pathway for high-energy density LiMnFePO4 cathodes

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Progress in Natural Science:Materials International 2023年第1期33卷 126-131页

作者： Shaoluan Huang Wenzhong Lin Liewu Li Pei Liu Tao Huang Zhencheng Huang Jinli kong Wei Xiong Wenwei Yu shenghua ye Jiangtao Hu Qianling Zhang Jianhong Liu Graphene Composite Research Center College of Chemistry and Environmental Engineering Shenzhen University Shenzhen Eigen–Equation Graphene Technology Co.Ltd.

Polyanion cathodes are credited for its thermal stability and better safety, no matter in lithium ion batteries or sodium ion batteries. Polyanion oxides with phosphate groups came to the public’s attention in 1997, and the representative material is LiFePO4, which has been widely applied and plays a huge role in the field of powder batteries and energy storage system. However, owing to the low lithiation potentials and storage sites, the energy densities of polyanion cathodes have been restricted, resulting of low-endurance and limited application scenarios. Accordingly, here, we use cheap and environmental friendly raw materials as precursors to synthesis high energy density LiMn0.6Fe0.4PO4@C cathode by a simple spray-drying and high temperature calcination *** self-designed liquid polyacrylonitrile(LPAN) is added for the intention of nanoparticle coating, conductive network construction and particle granulation. The low-cost and carbon-coated LiMn0.6Fe0.4PO4cathode exhibits excellent reversible capacity, low electrochemical polarization and excellent rate capacity, which maintains93.5% capacity retention after cycling 1000 times at 5C. The work introduces a new avenue to fabricate olivine structure cathodes with outstanding electrochemical performance for the high energy density lithium ion batteries.

关键词： Polyanion cathode Liquid polyacrylonitrile Cost effective High energy density High stability

Modulating the electronic spin state by constructing dual-metal atomic pairs for activating the dynamic site of oxygen reduction reaction

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Nano Research 2023年第2期16卷 1869-1877页

作者： shenghua ye Shuhua Xie Yaqi Lei Xiuyuan Yang Jing Hu Lirong Zheng Zhida Chen Yonghuan Fu Xiangzhong Ren Yongliang Li Xiaoping Ouyang Qianling Zhang Jianhong Liu Xueliang Sun College of Chemistry and Environmental Engineering Graphene Composite Research CenterShenzhen UniversityShenzhen 518060China Department of Mechanical and Materials Engineering University of Western OntarioLondonOntario N6A 5B9Canada Shenzhen Eigen-Equation Graphene Technology Co.Ltd. Shenzhen 518000China Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China

In this study,dual-metal atomic pairs of manganese(Mn)-iron(Fe)binuclear sites(BNSs)with two conjoint MnN4 and FeN4 moieties(MnFeN8)anchored onto a graphite-like structure(GLS)(Mn-Fe BNSs/GLS)were *** binuclear MnFeN8 structure was verified experimentally and *** measurements and Gaussian calculations reveal that this unique Mn-Fe BNSs exhibit strong short-range electronic interaction between Mn and Fe sites,which decouples two paired d electrons in Fe sites,thereby transforming Fe sites from an intermediate to a high spin *** optimal electronic configuration of Fe sites and their binuclear structure facilitate an oxygen reduction reaction(ORR)thermodynamically and dynamically,respectively,endowing Mn-Fe BNSs with improved ORR performance.

关键词： manganese(Mn)-iron(Fe)binuclear sites synergistic effect spin state oxygen reduction reaction

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光纤干涉绝对测距技术

中国机械工程 1999年第9期10卷 1019-1021页

作者：段发阶叶声华天津大学天津市300072

提出一种利用短扫描导轨（１００ｍｍ）实现１ｍ以上绝对距离测量的光纤干涉测距新方法：测量系统由定位干涉仪和扫描干涉仪组成，定位干涉仪采用准白光光源实现测量中的定位瞄准，扫描干涉仪完成距离的测量。此外定位干涉仪采用... 详细信息

提出一种利用短扫描导轨（１００ｍｍ）实现１ｍ以上绝对距离测量的光纤干涉测距新方法：测量系统由定位干涉仪和扫描干涉仪组成，定位干涉仪采用准白光光源实现测量中的定位瞄准，扫描干涉仪完成距离的测量。此外定位干涉仪采用多组光纤干涉结构，各组光纤的光程差由自身系统进行标定，从而实现量程的倍增。实验表明，测量精度达１０－５。

关键词：光纤干涉仪自标定绝对测距准白光

Optic Fiber Interferometer for Absolute Distance Measurement

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Chinese Journal of Lasers 1997年第5期B6卷 435-440页

作者： WANG Zhong HONG Haitao XIAO Hai SUN Changku MENG Yan ye shenghua (State Key Laboratory of Precision Measuring Technology and Instruments,Tianjin University, Tianjin 300072, China) Tianjin Univ Tianjin China

A synthesized scheme is presented to solve the ambiguity problems in ab-solute distance measurement, the principle and the structure of the system is introduced. The digital signal process for fast positioning is discussed in detail. Meanwhile, an expansion method is put forward to expand the dynamic range of the optic fiber interferometry system. Some experimental results are given.

关键词： absolute distance measurement optic fiber interferometer digital signal process