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Sulfur doped iron-nitrogen-hard carbon nanosheets as efficient and robust noble metal-free catalysts for oxygen reduction reaction in PEMFC

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Journal of Energy Chemistry 2024年第2期89卷 422-433,I0010页

作者： Bin Liu Jiawang Li Bowen yan Qi Wei Xingyu Wen Huarui Xie Huan He Pei Kang Shen Zhi qun Tian Collaborative Innovation Center of Sustainable Energy Materials School of Physical Science and TechnologyGuangxi UniversityGuangxi Key Laboratory of Electrochemical Energy MaterialsState Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite StructuresNanning 530004GuangxiChina

Transition metal-nitrogen-carbon(M-N-C)as a promising substitute for the conventional noble metalbased catalyst still suffers from low activity and durability for oxygen reduction reaction(ORR)in proton exchange membrane fuel cells(PEMFCs).To tackle the issue,herein,a new type of sulfur-doped ironnitrogen-hard carbon(S-Fe-N-HC)nanosheets with high activity and durability in acid media were developed by using a newly synthesized precursor of amide-based polymer with Fe ions based on copolymerizing two monomers of 2,5-thiophene dicarboxylic acid(TDA)as S source and 1,8-diaminonaphthalene(DAN)as N source via an amination *** as-synthesized S-Fe-N-HC features highly dispersed atomic Fe Nxmoieties embedded into rich thiophene-S doped hard carbon nanosheets filled with highly twisted graphite-like microcrystals,which is distinguished from the majority of M-N-C with soft or graphitic carbon *** unique characteristics endow S-Fe-N-HC with high ORR activity and outstanding durability in 0.5 M H_(2)SO_(4).Its initial half-wave potential is 0.80 V and the corresponding loss is only 21 m V after 30,000 ***,its practical PEMFC performance is a maximum power output of 628.0 mW cm^(-2)and a slight power density loss is 83.0 m W cm^(-2)after 200-cycle practical ***,theoretical calculation shows that the activity of Fe Nxmoieties on ORR can be further enhanced by sulfur doping at meta-site near fen_(4)*** results evidently demonstrate that the dual effect of hard carbon substrate and S doping derived from the precursor platform of amid-polymers can effectively enhance the activity and durability of Fe-N-C catalysts,providing a new guidance for developing advanced M-N-C catalysts for ORR.

关键词： Transition metal-nitrogen-carbon Oxygen reduction reaction Hard carbon Amide based polymer reaction Proton exchange membrane cells

基于会计行业转型升级需要的行业指导型产教融合模式探讨

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江苏商论 2024年第1期 119-121,141页

作者：杨群芬浙江商业职业技术学院浙江杭州310013

目前会计行业受到信息技术行业的影响而转型升级,会计人才需求受到行业转型升级的影响也在发生变化。然而人才供给跟不上人才需求的变化,导致低层次人才过剩,而高层次人才严重不足。本文通过建立行业指导型的产教融合模式,分析其对高职... 详细信息

目前会计行业受到信息技术行业的影响而转型升级,会计人才需求受到行业转型升级的影响也在发生变化。然而人才供给跟不上人才需求的变化,导致低层次人才过剩,而高层次人才严重不足。本文通过建立行业指导型的产教融合模式,分析其对高职院校会计专业人才培养方案的影响,从而实现提升会计人才供给侧与人才需求侧的契合度。

关键词：信息技术转型升级产教融合合作育人

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生态文明建设的价值审视

吉林工程技术师范学院学报 2024年第1期40卷 93-96页

作者：陈芬李卓群长沙理工大学湖南长沙410114

生态文明建设的价值目标,是使工业文明生态化;其价值立场应当超越人类中心主义,将人与自然生命共同体作为人与自然关系发展的基本准则;其价值追求是实现生态正义,防范因资本逻辑所导致的少数个人或集团因追求私利而给整个人类带来生存... 详细信息

生态文明建设的价值目标,是使工业文明生态化;其价值立场应当超越人类中心主义,将人与自然生命共同体作为人与自然关系发展的基本准则;其价值追求是实现生态正义,防范因资本逻辑所导致的少数个人或集团因追求私利而给整个人类带来生存环境危机;人与自然和谐共生是社会主义生态文明建设的价值旨归。

关键词：生态文明建设价值取向人与自然和谐共生

Influence of structure and material on the vibration modal characteristics of novel combined flexible road wheel

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Defence Technology（防务技术） 2022年第7期18卷 1179-1189页

作者： yao-ji Deng you-qun Zhao fen Lin Li-guo Zang College of Mechanical Engineering Yangzhou UniversityYangzhou 225127China College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Automobile&Rail Transit Nanjing Institute of TechnologyNanjing 211167China

Aiming at the independent development of tracked vehicles,it is urgent to improve its mobility,passability and ride comfort,a new type of flexible road wheel with a“wheel-hinge-hub”combined structure is proposed in this *** vibration model characteristics of the flexible road wheel were studied by the combination of numerical simulation and *** superelasticity of rubber is obtained through uniaxial tensile experiment of the material and a detail three-dimensional nolinear finite element model of the flexible road wheel is established through finite element software *** free vibration equation of the flexible road wheel is solved by Lanczos vector direct superposition method,and its predicted modes and natural frequencies are compared with experimental results,which verifies the accuracy and reliability of the established finite element *** this basis,the effects of various key structural or material factors on the natural frequencies of the flexible road wheel are studied using orthogonal experimental design ***,the vibration modal characteristics of the flexible road wheel are also compared with those of the rigid road *** research results provide a theoretical basis for the vibration and noise reduction of flexible road wheel.

关键词： Flexible road wheel Orthogonal experimental design Vibration modal Tracked vehicle Finite element analysis

Knoevenagel condensation catalysed by poly(vinyl chloride) supported tetraethylenepentamine (PVC-TEPA)

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Chinese Chemical Letters 2007年第3期18卷 266-268页

作者： fen Dong yi qun Li Rong feng Dai Department of Chemistry Jinan University Guangzhou 510632 China

Poly（vinyl chloride） supported tetraethylenepentamine （PVC-TEPA） has been found to be an efficient catalyst for the Knoevenagel condensation. A wide range of aromatic aldehydes easily undergo condensations with ethyl cyanoacetate and malononitrile in the commercial 95% ethanol in refluxing using PVC-TEPA as catalyst to afford the desired products of good purity in moderate to excellent yields. A recycling study confirmed that the catalyst could be reused, the yield of the desired condensation product were not reduced. The merits of this protocol are environmentally benign, simple operation, convenient work-up and good yields. Furthermore, the catalyst can easily be recovered and reused at five times with comparable yields.

关键词： Knoevenagel condensation PVC-supported tetraethylenepentamine Catalysis

Minimum Time Overtaking Problem of Vehicle Handling Inverse Dynamics Based on Two Kinds of Safe Distances

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Chinese Journal of Mechanical Engineering 2018年第6期31卷 207-216页

作者： you-qun Zhao Xing-Long Zhang Wen-Xin Zhang fen Lin College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics

Overtaking accidents caused by improper operations performed by a driver occur frequently. However, most stud?ies on overtaking safety have neglected research into driver control input. A novel method is proposed to obtain the driver control input during the overtaking process. Meanwhile, to improve the safety of overtaking, two types of safe distances, and the time of the overtaking are considered. Path constraints are established when considering the two types of safe distances. An optimal control model is established to solve the minimum time maneuver under multiple constraints. Using the Gauss pseudospectral method, the optimal control problem is converted into a nonlinear pro?gramming problem, which is then solved through sequential quadratic programming(SQP). In addition, the e ective?ness of the proposed method is verified based on the results of a Carsim simulation. The simulation results show that by adopting an inverse dynamics method to solve the manipulation problem of the vehicle’s minimum overtaking time, the manipulation capability of a vehicle in completing an overtaking safely within the minimum time can be obtained. This method can provide a reference for research into the active safety of manned and unmanned vehicles.

关键词： Handling inverse dynamics Safe distance Overtaking Optimal control Simulation

Protective mechanisms of micro RNA-27a against oxygen-glucose deprivation-induced injuries in hippocampal neurons

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Neural Regeneration Research 2016年第8期11卷 1285-1292页

作者： qun Cai Ting Wang Wen-jie yang Xing fen Department of Neonatology Children's Hospital of Soochow University Suzhou Jiangsu Province China Department of Emergency Affiliated Hospital of Nantong University Nantong Jiangsu Province China Medical College of Nantong University Nantong Jiangsu Province China

Hypoxic injuries during fetal distress have been shown to cause reduced expression of micro RNA-27a（mi R-27a）,which regulates sensitivity of cortical neurons to *** hypothesized that miR-27 a overexpression attenuates hypoxia- and ischemia-induced neuronal apoptosis by regulating FOXO1,an important transcription factor for regulating the oxidative stress ***-27 a mimic was transfected into hippocampal neurons to overexpress miR-27 *** showed increased hippocampal neuronal viability and decreased caspase-3 *** luciferase reporter gene system demonstrated that mi R-27 a directly binded to FOXO1 3′UTR in hippocampal neurons and inhibited FOXO1 expression,suggesting that FOXO1 was the target gene for mi R-27 *** findings confirm that mi R-27 a protects hippocampal neurons against oxygen-glucose deprivation-induced *** mechanism might be mediated by modulation of FOXO1 and apoptosis-related gene caspase-3 expression.

关键词： nerve regeneration brain injury miR-27a hypoxic-ischemic hippocampal neurons oxygen-glucose deprivation cell survival apoptosis caspase 3 FOX01 luciferase reporter gene system neuroprotection neural regeneration

Thermodynamic assessment of Mg-Ni-y system focusing on long-period stacking ordered phases in the Mg-rich corner

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Journal of Magnesium and Alloys 2022年第11期10卷 3250-3266页

作者： Cheng Liu qun Luo Qin-fen Gu Qian Li Kuo-Chih Chou State Key Laboratory of Advanced Special Steels&Shanghai Key Laboratory of Advanced Ferrometallurgy School of Materials Science and EngineeringShanghai UniversityShanghai 200444China Australian Synchrotron Clayton 3168Australia

The long-period stacking ordered phases(LPSOs) in Mg-Ni-y system have been attracting great interest as effective strengthening components because of their unique structural characteristics and deformation ***,the phase relationships in LPSOs are complicated and unclear,which restricts the design of advanced magnesium-based *** aim of the present work is to experimentally determine the phase equilibria relationships focusing on LPSOs and establish the thermodynamic description for Mg-Ni-y *** types of LPSOs,that is,14H,12R,18R and 10H,are confirmed through equilibrated alloys and high-resolution transmission electron microscopy(HR-TEM).The formation enthalpies of LPSOs(14H,12R,18R and 10H) are calculated based on density functional theories(DFT) calculations.A new ternary compound,termed as τ phase,is observed for the first time which is likely to be the distorted structure of 12R as determined from the TEM image which shows a 12-layer closed packing plane distance of 3.252nm and a shear angle of 83.2°between(0002) and(10■0) *** on the determined phase equilibria relationship,the Mg-Ni-y system is assessed and a selfconsistent description is obtained where the LPSOs are modeled as the stoichiometric *** comparison between the calculation result and experimental data suggests the accuracy of the present thermodynamic database in the Mg-rich corner.

关键词： LPSO phases Crystal structures Phase equilibria Thermodynamics

Influence Analysis of Machining and Installation Errors on the Radial Stiffness of a Non-Pneumatic Mechanical Elastic Wheel

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Chinese Journal of Mechanical Engineering 2018年第4期31卷 92-100页

作者： you-qun Zhao Zhen Xiao fen Lin Ming-Min Zhu yao-Ji Deng Department of Automotive Engineering College of Energy and Power EngineeringNanjing University of Aeronautics and Astronautics

Machining and installation errors are unavoidable in mechanical structures. However, the effect of errors on radial stiffness of the mechanical elastic wheel(ME-Wheel) is not considered in previous studies. To this end, the interval mathematical model and interval finite element model of the ME-Wheel were both established and compared with bench test results. The intercomparison of the influence of the machining and installation errors on the ME-Wheel radial stiffness revealed good consistency among the interval mathematical analysis, interval finite element simulation,and bench test results. Within the interval range of the ME-Wheel machining and installation errors, parametric analysis of the combined elastic rings was performed at different initial radial rigidity values. The results showed that the initial radial stiffness of the flexible tire body significantly influenced the ME-Wheel radial stiffness, and the inverse relationship between the hinge unit length or suspension hub and the radial stiffness was nonlinear. The radial stiffness of the ME-Wheel is predicted by using the interval algorithm for the first time, and the regularity of the radial stiffness between the error and the load on the ME-Wheel is studied, which will lay the foundation for the exact study of the ME-Wheel dynamic characteristics in the future.

关键词： Mechanical elastic wheel Stiffness characteristic Errors Interval algorithm Interval finite element