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Journal of Materials Science & Technology 2014年第8期30卷 759-764页

作者： Yanhong Chang Jing li bin Wang Hui Luo linjie Zhi School of Civil and Environmental Engineering University of Science and Technology Beijing Key Laboratory of Educational Ministry for High Efficient Mining and Safety in Metal Mine University of Science and Technology Beijing National Center for Nanoscience and Technology School of Chemical and Biological Engineering University of Science and Technology Beijing

Reduced graphene oxide-Fe3O4（rGO—Fe3O4） composite has been prepared via a facile and effective hydrothermal method by synthesizing Fe3O4 nanospheres on the planes of reduced graphene oxide（rGO）.Characterizations suggest the successful attachment of Fe3O4 nanospheres to rGO *** rGO—Fe3O4composite（66.7 wt%of Fe3O4 in the composite） exhibits a stable capacity of 668 mAh g-1 without noticeable fading for up to 200 cycles in the voltage range of 0.001—3.0 V,and the superior performance of rGO-Fe3O4 is clearly established by comparison of the results with those from bare Fe3O4 nanospheres（capacity declined to 117 mAh g-1 only at the 200 th cycle）.The excellent electrochemical performance of rGO—Fe3O4 composite can be attributed to the fact that the uniform dispersion of the Fe3O4 nanospheres growing on the rGO sheets avoids aggregation during li uptake-release cycling,which is desired for cycle ***,the rGO sheets afford not only elastic buffer to alleviate the volume variations of Fe3O4nanospheres,but also good ionic and electronic transport medium in the electrode.

关键词： Facile synthetic approach rGO Fe3O4 nanosphcres Composite lithium-ion batteries High performance

Personalized project recommendation on Git Hub

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Science China(Information Sciences) 2018年第5期61卷 87-100页

作者： Xiaobing SUN Wenyuan XU Xin XIA xiang CHEN bin li School of Information Engineering Yangzhou University State Key Laboratory for Novel Software Technology Nanjing University Information Technology Research Base of Civil Aviation Administration of China Civil Aviation University of China Faculty of Information Technology Monash University School of Computer Science and Technology Nantong University

Git Hub is a software development platform that facilitates collaboration and participation in project development. Typically, developers search for relevant projects in order to reuse functions and identify useful features. Recommending suitable projects for developers can save their time. However,finding suitable projects among many projects on Git Hub is difficult. In addition, different users may have different requirements. A recommendation system would help developers by reducing the time required to find suitable projects. In this paper, we propose an approach to recommend projects that considers developer behaviors and project features. The proposed approach automatically recommends the top-N most relevant software projects. We also integrate user feedback to improve recommendation accuracy. The results of an empirical study using data crawled from Git Hub demonstrate that the proposed approach can efficiently recommend relevant software projects with relatively high precision.

关键词： software recommendation developer behavior GitH ub user feedback personalized recommendation

Swimming Behavior Analysis Based on Bacterial Chemotaxis in Solution

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Journal of Bionic Engineering 2012年第3期9卷 315-321页

作者： bin He Zhipeng Wang Chaoqun liu Yonggang li Runjie Shen Department of Control Science&Engineering Tongji UniversityShanghai 200090P.R.China

Microrobots is playing more and more important roles for medical applications, such as targeting tumoral lesions for therapeutic purposes, Minimally Invasive Surgery （MIS） and highly localized drug delivery. However, energy efficient pro- pulsion system poses significant challenges for the implementation of such mobile robots. Flagellated chemotactic bacteria can be used as an effective integrated propulsion system for microrobots. In this paper, we proposed a new type of propulsion method that is inspired by the motility mechanism of flagellated chemotactic bacteria in different pH gradients. The pH gradient field was established in solution through electrolysis method. The distribution of the pH values in solution was measured with pH indicator and analyzed with image processing technology, and the mechanism by which the pH values changed was also discussed. The swimming speed and direction of the bacteria were studied experimentally. Through analyzing the key pa- rameters, such as stabilization time and electrode voltage, the optimal design of propulsion mechanism based on bacteria motion in the pH gradient field was proven.

关键词： microrobots bacteria drive pH gradient chemotaxis

Research on DC Protection Strategy in Multi-Terminal Hybrid HVDC System

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Engineering 2021年第8期7卷 1064-1075页

作者： Yuping Zheng Jiawei He bin li Tonghua Wua Wei Dai Ye li State Key Laboratory of Smart Grid Protection and Control State Grid Electric Power Research Institute(NARI Group Corporation)Nanjing 211106China Key Laboratory of Smart Grid of Ministry of Education Tianjin UniversityTianjin 300072China College of Energy and Electrical Engineering Hohai UniversityNanjing 210098China

Multi-terminal hybrid high-voltage direct current(HVDC)systems have been developed quickly in recent years in power transmission ***,for voltage-source converter(VSC)stations in hybrid HVDC systems,no direct current(DC)filters are *** addition,the DC reactor is also not installed at the line end because the DC fault can be limited by the converter *** means that the boundary element at the line end is absent,and the single-ended protections used in line commutated converter(LCC)based HVDC(LCC-HVDC)systems or VSC-HVDC systems cannot distinguish the fault line in multi-terminal hybrid HVDC *** paper proposes a novel singleended DC protection strategy suitable for the multi-terminal hybrid HVDC system,which mainly applies the transient information and active injection concept to detect and distinguish the fault *** with the single-ended protections used in LCC-HVDC and VSC-HVDC systems,the proposed protection strategy is not dependent on the line boundary element and is thus suitable for the multiterminal hybrid HVDC *** corresponding simulation cases based on power systems computer aided design(PSCAD)/electromagnetic transients including DC(EMTDC)are carried out to verify the superiority of the proposed protection.

关键词： Multi-terminal hybrid HVDC system Single-ended protection Transient information Active injection

HCAⅡ-inspired Catalysts for Making Carbon Dioxide-based Copolymers:The Role of Metal-hydroxide Bond

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Chinese Journal of Polymer Science 2018年第2期36卷 139-139,140-148页

作者： Yang li Ying-Ying Zhang bin liu Xing-Hong Zhang Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science&EngineeringZhejiang UniversityHangzhou 310027China

The general characteristics of the active center of the catalysts（including zinc-cobalt（III） double metal cyanide complex [Zn-Co（Ⅲ） DMCC]） for the copolymerization reaction of carbon dioxide（CO2） with epoxide are summarized. By comparing the active center, catalytic performance of the Zn-Co（Ⅲ） DMCC（and other catalysts） with HCAII enzyme in the organism for activating CO2（COS and CS2）, we proposed that the metal-hydroxide bond（M-OH）, which is the real catalytic center of human carbonic anhydride Ⅱ（HCAⅡ）, is also the catalytic（initiating） center for the copolymerization. It accelerates the copolymerization and forms a closed catalytic cycle through the chain transfer reaction to water（and thus strictly meets the definition of the catalyst）. In addition, the metal-hydroxide bond catalysis could well explain the oxygen/sulfur exchange reaction（O/S ER） in metal（Zn, Cr）-catalyzed copolymerization of COS（and CS2） with epoxides. Therefore, it is very promising to learn from HCAⅡ enzyme to develop biomimetic catalyst for highly active CO2/epoxide copolymerization in a well-controlled manner under mild conditions.

关键词： Carbon dioxide Carbonic anhydrase (CA) Copolymerization Metal-hydroxide bond

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分块式同步折展主镜保护机构设计及验证

光学技术 2024年第5期50卷 526-532页

作者：文丰艾唐金龙芮道满张程李文茹鲜浩自适应光学全国重点实验室四川成都610209

主镜是望远镜的核心部分,需要设计保护机构以维持其性能、延长主镜膜层的使用寿命。在此背景上,针对某2.5m大口径光学望远镜结构特点及项目需求,设计了分块式同步折展主镜保护机构。重点对复合夹层材料的保护盖板进行了铺层优化设计,使... 详细信息

主镜是望远镜的核心部分,需要设计保护机构以维持其性能、延长主镜膜层的使用寿命。在此背景上,针对某2.5m大口径光学望远镜结构特点及项目需求,设计了分块式同步折展主镜保护机构。重点对复合夹层材料的保护盖板进行了铺层优化设计,使其在满足轻量化需求的同时,刚度强度达到相关要求(盖板质量20Hz,在八级风载和1kg物块冲击下Tsai-Wu<1)。同时通过对机构折展运动的驱动设计及控制方式试验,可在规定时间内实现多扇同步驱动,单向折展运动时间约为52s。此设计对主镜甚至整个主镜筒内部结构都产生了良好的保护效果。该设计为国内大口径望远镜的主镜保护机构提供了新的思路及验证,对其余主镜保护结构的研究具有一定的参考意义。

关键词：主镜保护轻量化设计复合材料铺层折展机构

Efficient catalytic hydrogen generation by intermetallic platinum-lead nanostructures with highly tunable porous feature

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Science Bulletin 2019年第1期64卷 36-43页

作者： bin E lingzheng Bu Qi Shao Yujing li Xiaoqing Huang College of Chemistry Chemical Engineering and Materials Science Soochow University Department of Materials Science and Engineering China University of Petroleum College of Materials Beijing Institute of Technology

The water-gas shift(WGS) reaction is an essential industrial reaction for upgrading hydrogen(H2) by removing carbon monoxide(CO), while highly efficient platinum(Pt)-based catalysts for WGS with simultaneously high activity and stability are still yet to be developed due to the poisoning issue during the reaction. Herein, we report on the porous PtPb peanut nanocrystals(porous PtPb PNCs) and porous PtPb octahedron nanocrystals(porous PtPb ONCs) with controllable ratios of Pt/Pb as extremely active and stable catalysts towards WGS reaction. It exhibits the composition-dependent activity with porous PtPb PNCs-40/ZnO being the most active for WGS to H_2, 16.9 times higher than that of the commercial Pt/C. The porous PtPb PNCs-40/ZnO also display outstanding durability with barely activity decay and negligible structure and composition changes after ten successive reaction cycles. X-ray photoelectron spectroscopy(XPS) results reveal that the suitable binding energy of Pt 4f_(7/2) and the high ratio of Pt(0)to Pt(II) in porous PtPb PNCs/ZnO and porous PtPb ONCs/ZnO are crucial for the enhanced WGS *** CO stripping results indicate the optimized CO adsorption strength on the Pt surface ensure the excellent WGS activity and the outstanding durability. The present work demonstrates an important advance in tuning the porous metal nanomaterials as highly efficient and durable catalysts for catalysis,energy conversion and beyond.

关键词： Porous Selective etching Hydrogen Pt-Pb Water-gas shift

Efficient Copolymerization of Ethylene with Polar Divinyl Monomer by Phosphino-Phenolate Nickel Catalyst

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Chinese Journal of Chemistry 2023年第9期41卷 1037-1044页

作者： Fei Wang Xu-ling Wang li Pan bin Wang Yue-Sheng li Tianjin Key Lab of Composite&Functional Materials School of Material Science and EngineeringTianjin UniversityTianjin 300072China College of Chemistry and Chemical Engineering Yantai UniversityYantaiShandong 264005China

Direct copolymerization of olefin with polar monomers via a coordination-insertion mechanism appears as the most efficient and at-tractive method to prepare functionalized ***,we carried out direct copolymerization of ethylene and allyl acrylate by a bulky phosphino-phenolate nickel catalyst,in which high-molecular-weight copolymers bearing polar five-membered and six-membered ring structures were *** NMR and FT-I R analyses revealed multiplex structure of the obtained copolymers,in which both the noncyclic structural units bearing pendant allyl moiety(A)as well as acrylate moiety(B)and the cyclic structural units,y-butyrolactones(C)andδ-valerolactone(D)were ***,the content of different structural units of the produced copolymer could be tuned by adjusting the concentration of the ***,we also proved that the nick-el-based catalyst could produce related copolymers with significantly enhanced copolymer molecular weights in the copolymeriza-tion of allyl acrylate and ethylene compared with the palladium-based catalyst under the same conditions.

关键词： Coordination and insertion Copolymerization Nickel Polar monomer Polyolefin

Percutaneous management of atrium and lung perforation: A case report

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World Journal of Clinical Cases 2019年第24期7卷 4327-4333页

作者： Xu Zhou Feng Ze Ding li Xue-bin li Department of Cardiac Electrophysiology Peking University People’s Hospital

BACKGROUND Cardiac perforation by a transvenous lead is an uncommon but serious complication. Delayed perforation, defined as migration and perforation of an implanted lead at least 1 mo after implantation, is exceedingly rare and prone to underdiagnosis, and its optimal management is currently unclear. We report an uneventful transvenous extraction of an active fixation lead that led to delayed perforation of the right atrium, pericardium, and lung, disclosed 2 mo after *** SUMMARY A 61-year-old woman with atrial lead perforation was transferred to our *** had a dual-chamber pacemaker with active fixation leads implanted 8 mo previously. At 2 mo after implantation, she complained of chest pain and hemoptysis. Chest computed tomography revealed atrial lead migration into the lung. No pericardial or pleural effusion was detected. She underwent transvenous lead extraction in the electrophysiology room with surgical *** percutaneous subxiphoid pericardial puncture was performed first, and a pigtail catheter was left in the pericardial sac throughout the procedure. Then, a new active fixation lead was implanted at a different site with less tension. After the active screw was retracted, the culprit atrial lead was explanted successfully with simple traction. There were no complications during or after the *** patient recovered well and follow-up was *** Percutaneous management of perforated active fixation lead outside the pericardial sac under surgical backup is safe and effective.

关键词： Lead perforation Transvenous lead extraction Percutaneous subxiphoid pericardial puncture Pacemaker lead Active fixation Case report

Synthesis and Crystal Structure of a Sodium Monosulfuron-ester (N-[2'-(4-Methyl)pyrimidinyl]-2-carbomethoxy Benzyl Sulfonylurea Sodium)

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1414-1417页

作者： KOU Jun-Jie li Zheng-Ming SONG Hai-bin National Pesticide Engineering Research Center State Key Laboratory of Elemento-organic Chemistry Nankai University Tianjin 300071 China

Monosulfuron-ester is a novel sulfonylurea herbicide with ultra-low dosage Herein sodium monosulfuron-ester was synthesized and its crystal structure was determined by X-ray diffraction method. The title compound belongs to monoclinic, space group P21/c with a = 9.335（5）, b = 20.632（12）, c = 13.853（8） A, β = 107.193（9）°, Mr = 487.46, Z = 4, Dc = 1.270 g/cm^3, μ = 0.293 mm^-1, F（000） = 1015, R = 0.0859 and wR = 0.2633. In the title compound, Na coordinates with N（1）, O（1） and O（3） from one monosulfuron-ester molecule, N（4A） and O（5A） from the other monosulfuron-ester molecule and one oxygen atom from DMSO to give six coordination bonds.

关键词： sulfonylurea sodium monosulfuron-ester crystal structure