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Nano Research 2024年第8期17卷 6951-6959页

作者： Mengxuan li linfeng Yu Hai liu Chuanyi Zhang jiazhan li liang Luo Xiaoming Sun State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

Zn-air batteries(ZABs)as a potential energy conversion system suffer from low power density(typically≤200 mW·cm^(−2)).Recently,three-dimensional(3D)integrated air cathodes have demonstrated promising performance over traditional twodimensional(2D)plane ones,which is ascribed to enriched active sites and enhanced diffusion,but without experimental ***,we applied a bubble pump consumption chronoamperometry(BPCC)method to quantitatively identify the gas diffusion coefficient(D)and effective catalytic sites density(ρEC)of the integrated air cathodes for ***,the D andρEC values can instruct consequent optimization on the growth of Co embedded N-doped carbon nanotubes(CoNCNTs)on carbon fiber paper(CFP)and aerophilicity tuning,giving 4 times D and 1.3 timesρEC over the conventional 2D Pt/C-CFP *** a result,using the CoNCNTs with half-wave potential of merely 0.78 V ***(Pt/C:0.89 V ***),the superaerophilic CoNCNTs-CFP cathode-based ZABs exhibited a superior peak power density of 245 mW·cm^(−2)over traditional 2D Pt/C-CFP counterparts,breaking the threshold of 200 mW·cm^(−2).This work reveals the intrinsic feature of the 3D integrated air cathodes by yielding exact D andρEC values,and demonstrates the feasibility of BPCC method for the optimization of integrated electrodes,bypassing trial-and-error strategy.

关键词： Zn-air batteries three-dimensional(3D)integrated air cathodes superaerophilic gas diffusion coefficient effective catalytic sites density

结合语法增强与噪声削减的方面级情感分析模型

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计算机工程与应用 2024年第13期60卷 152-161页

作者：汪红松李嘉展叶浩贤陶然华南师范大学软件学院广东佛山528225

方面级情感分析的主要目标是判断句子中给定方面词的情感极性。最近的研究主要采用依存句法信息,隐式地关联方面词与目标词之间的情感交互信息。但结合依存句法信息方法,缺乏识别以方面词为中心的局部上下文信息。此外,对繁杂的语法信... 详细信息

方面级情感分析的主要目标是判断句子中给定方面词的情感极性。最近的研究主要采用依存句法信息,隐式地关联方面词与目标词之间的情感交互信息。但结合依存句法信息方法,缺乏识别以方面词为中心的局部上下文信息。此外,对繁杂的语法信息进行等价建模,会引入损害模型性能的噪声。针对以往研究中存在的问题,提出了结合语法增强与噪声削减的神经网络模型。该方法在依存句法信息基础上融合了成分信息,使模型不仅能关注词与词之间的全局依赖信息,同时能关注以方面词为中心的局部依赖信息。同时,为了降低语法信息的噪声干扰,模型以依存句法树的距离信息为依据,弱化了远距离的噪声干扰。最后,模型在四个基准数据集上进行了实验,并在所有数据集上的性能都优于基线模型。

关键词：方面级情感分析依存句法成分信息位置信息

Phosphorus induced activity-enhancement of Fe-N-C catalysts for high temperature polymer electrolyte membrane fuel cells

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Nano Research 2023年第5期16卷 6531-6536页

作者： Xiangrong Jin Yajie li Hao Sun Xiangxiang Gao jiazhan li Zhi Lü Wen liu Xiaoming Sun State Key Laboratory of Chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China Engineering Research Center of Advanced Rare Earth Materials Department of ChemistryTsinghua UniversityBeijing 100084China

Fe-N-C materials with atomically dispersed Fe–N_(4) sites could tolerate the poisoning of phosphate,is regarded as the most promising alternative to costly Pt-based catalysts for the oxygen reduction in high temperature polymer electrolyte membrane fuel cells(HT-PEMFCs).However,they still face the critical issue of insufficient activity in phosphoric ***,we demonstrate a P-doping strategy to increase the activity of Fe-N-C catalyst via a feasible one-pot method.X-ray absorption spectroscopy and electron microscopy with atomic resolution indicated that the P atom is bonded with the N in Fe–N_(4) site through C *** as prepared Fe-NCP catalyst shows a half-wave potential of 0.75 V(*** hydrogen electrode(RHE),0.1 M H_(3)PO_(4)),which is 60 and 40 mV higher than that of Fe-NC and commercial Pt/C catalysts,*** importantly,the Fe-NCP catalyst could deliver a peak power density of 357 mW·cm^(−2)in a high temperature fuel cell(160℃),exceeding the non-noble-metal catalysts ever *** enhancement of activity is attributed to the increasing charge density and poisoning tolerance of Fe–N_(4) caused by neighboring *** work not only promotes the practical application of Fe-N-C materials in HT-PEMFCs,but also provides a feasible P-doping method for regulating the structure of single atom site.

关键词： iron nitrogen carbon heteroatomic doping phosphorous tolerance high temperature polymer electrolyte membrane fuel cells

Regulating electronic structure of CoN_(4)with axial Co-S for promoting oxygen reduction and Zn-air battery performance

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Nano Research 2023年第4期16卷 4211-4218页

作者： Chang Chen Zhiqiang Chen Junxi Zhong Xin Song Dongfang Chen Shoujie liu Weng-Chon Cheong jiazhan li Xin Tan Chang He Jiaqi Zhang Di liu Qiuhua Yuan Chen Chen Qing Peng Yadong li Department of Chemistry Tsinghua UniversityBeijing 100084China Beijing Key Laboratory of Research and Application for Aerospace Green Propellants Beijing Institute of Aerospace Testing TechnologyBeijing 100048China College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China State Key Laboratory of Automtive Safety and Energy Tsinghua UniversityBeijing 100084China Chemistry and Chemical Engineering Guangdong Laboratory Shantou 515031China Department of Physics and Chemistry Faculty of Science and TechnologyUniversity of MacaoMacao 999078China

Regulating the coordination environment of transition-metal based materials in the axial direction with heteroatoms has shown great potential in boosting the oxygen reduction reaction(ORR).The coordination configuration and the regulation method are pivotal and ***,we report a combined strategy of matrix-activization and controlled-induction to modify the CoN_(4)site by axial coordination of Co-S(Co1N_(4)-S_(1)),which was validated by the aberration-corrected electron microscopy and X-ray absorption fine structure *** optimal Co1N_(4)-S_(1)exhibits an excellent alkaline ORR activity,according to the half-wave potential(0.897 V *** hydrogen electrode(RHE)),Tafel slope(24.67 mV/dec),and kinetic current ***,the Co1N_(4)-S_(1)based Zn-air battery displays a high power density of 187.55 mW/cm^(2)and an outstanding charge-discharge cycling stability for 160 h,demonstrating the promising application *** calculations indicate that the better regulation of CoN_(4)on electronic structure and thus the highly efficient ORR performance can be achieved by axial Co-S.

关键词： electronic structure regulation axial Co-S coordination single-atom Co oxygen reduction Zn-air battery

Atomically dispersed manganese catalyst for oxygen reduction in protonexchange membrane fuel cells

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Atomically dispersed manganese catalyst for oxygen reduction...

中国化学会2019能源材料和缺陷化学研讨会

作者： jiazhan li Zhen-Bo Wang MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical Engineering Harbin Institute of Technology

＜正＞Replacing expensive and scarce platinum group metal（PGM） catalysts with high-performance and cost-effective PGM-free catalysts is the key to realizing the large-scale application of protonexchange membrane fuel cells（PEMFCs）. Significant progress have been achieved in recent years, especially for the development of atomically dispersed catalyst, which enable the maximum utilization of metal atoms and significantly increase the density of active sites. However, the state of the art PGM-free catalysts still suffer from insufficient activity and stability in acid media,

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文本方面级情感分析方法研究综述

软件导刊 2023年第9期22卷 1-8页

作者：汪红松李嘉展曾碧卿华南师范大学软件学院广东佛山528225

方面级情感分析(ABSA)作为细粒度情感分析领域的子任务,旨在分析给定目标中方面术语的情感极性。近年来,随着社交媒体的反馈信息增多,ABSA引起了许多研究者关注。为了适应不同场景下的ABSA,研究人员不断设计新的方法和技术来处理不同问... 详细信息

方面级情感分析(ABSA)作为细粒度情感分析领域的子任务,旨在分析给定目标中方面术语的情感极性。近年来,随着社交媒体的反馈信息增多,ABSA引起了许多研究者关注。为了适应不同场景下的ABSA,研究人员不断设计新的方法和技术来处理不同问题。首先对方面级情感分析进行概述,然后针对细粒度情感分析子任务,阐述不同场景下ABSA的研究方法及特点,最后通过回顾ABSA新出现的话题,展望ABSA研究的发展趋势,以期为该领域的研究提供一定的参考借鉴。

关键词：方面级情感分析情感分类深度学习机器学习

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Low contact resistivity and long-term thermal stability of Nb0.8Ti0.2FeSb/Ti thermoelectric junction

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Journal of Materials Science & Technology 2020年第5期40卷 113-118页

作者： Zhijie Huang li Yin Chaoliang Hu Jiajun Shen Tiejun Zhu Qian Zhang Kaiyang Xia jiazhan Xin Xinbing Zhao State Key Laboratory of Silicon Materials and School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China Department of Materials Science and Engineering Institute of Materials Genome&Big DataHarbin Institute of TechnologyShenzhen 518055China

Although half-Heusler compounds are quite promising for thermoelectric power generation,there is only limited research on the interfacial structure between metal electrode and half-Heusler compounds for device *** work reports on the characteristics of Nb0.8Ti0.2Fe Sb/Ti junction and its evolution behavior during 973 *** Nb0.8Ti0.2Fe Sb/Ti interface consists of one Ti0.9Fe0.1 layer and one Fe-poor *** is an Ohmic contact and a low contact resistivity(0.15μΩcm^-2)in this junction,on account of the matching of working functions between Nb0.8Ti0.2Fe Sb and Ti0.9Fe0.1 *** high doping of Ti high carrier concentration in Nb Fe Sb matrix leads to a high carrier concentration,which results in inducing a large tunneling current at this *** aging treatment at 973 K,the Fe-poor layer and the Ti0.9 Fe0.1 layer continues to expand,resulting in the increase of the thickness of the interfacial layer and the contact *** interfacial electrical is only 1.9μcm^-2 after 25 days’*** thickness of the interface layer has a good linear relation with the square root of aging time,which firmly indicates that the growth of the layer is determined by mutual diffusion of Fe and Ti atoms across the *** low contract resistivity and long-time thermal stability demonstrate the great potential of Nb0.8Ti0.2Fe Sb/Ti thermoelectric junction in high efficiency half-Heusler TE devices.

关键词： Thermoelectric materials Half-Heusler alloys Electrode Contact resistivity Thermal stability

钢-UHPC组合板环氧黏结界面抗剪与抗拉性能试验

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土木工程学报 2023年第1期56卷 25-36,56页

作者：李聪陈宝春谢泽豪苏家战广西大学广西南宁530004 福州大学福建福州350108 桥梁技术创新与风险防治国家级国际联合研究中心福建福州350108 福建省交通规划设计院有限公司福建福州35000

文章以预制UHPC板与钢板采用环氧树脂黏结剂连接的组合结构为对象,开展了连接界面抗剪与抗拉的试验研究。试验结果表明,试件中的环氧树脂黏结剂和UHPC材料本身均保持完好;破坏位置,抗剪试件为黏结剂与钢板交界面,抗拉试件为黏结剂与UHP... 详细信息

文章以预制UHPC板与钢板采用环氧树脂黏结剂连接的组合结构为对象,开展了连接界面抗剪与抗拉的试验研究。试验结果表明,试件中的环氧树脂黏结剂和UHPC材料本身均保持完好;破坏位置,抗剪试件为黏结剂与钢板交界面,抗拉试件为黏结剂与UHPC的交接面;破坏性质为脆性,交接面出现滑移或分离后快速丧失承载力。抗剪强度受黏结面积影响不大,实测值平均值2.59MPa,抗剪强度设计值为1.36MPa。抗拉强度与黏结面积有关,当试件尺寸由160mm增大至200mm,实测值分别为2.74MPa和1.86MPa,降幅超过30%,抗拉强度设计值为0.78MPa。UHPC中钢纤维掺量在1%~2%范围内对抗拉黏结强度影响可忽略。建立了钢-UHPC组合板有限元模型进行受力分析。分析表明,在轮载作用下,黏结层以受剪为主,沿横桥向最为不利;最不利荷载工况的最大剪应力和竖向拉应力分别1.11MPa和0.15MPa,均低于黏结剂抗剪和抗拉强度设计值。根据试验和实例分析结果,考虑到黏结剂连接脆性破坏特性,建议重视胶结界面的处理,重点关注抗剪强度问题。

关键词：预制UHPC板环氧黏结剂抗剪抗拉黏结强度黏结面积有限元分析

转晶剂与蒸压参数对磷石膏制备α半水石膏的影响

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无机盐工业 2022年第8期54卷 132-137页

作者：黎明川韦家崭陈平段鹏选桂林理工大学材料科学与工程学院广西桂林541004 桂林理工大学广西建筑新能源与节能重点实验室桂林理工大学广西工业废渣建材资源利用工程技术研究中心桂林理工大学广西有色金属隐伏矿床勘查及材料开发协同创新中心

以经盐溶液预处理的磷石膏为原料,以乙二胺四乙酸(EDTA)和顺丁烯二酸酐为复合转晶剂,采用蒸压法制备α半水石膏。借助扫描电镜(SEM)、X射线衍射(XRD)分析研究了复合转晶剂掺量、pH、蒸压温度对生成α半水石膏的晶体形貌、物相组成的影... 详细信息

以经盐溶液预处理的磷石膏为原料,以乙二胺四乙酸(EDTA)和顺丁烯二酸酐为复合转晶剂,采用蒸压法制备α半水石膏。借助扫描电镜(SEM)、X射线衍射(XRD)分析研究了复合转晶剂掺量、pH、蒸压温度对生成α半水石膏的晶体形貌、物相组成的影响。研究结果表明,复合转晶剂中EDTA的最佳掺量(质量分数)为0.4%、顺丁烯二酸酐的最佳掺量(质量分数)为0.3%,溶液最佳pH为7.5,最佳蒸压温度为140℃。在此条件下制得的α半水石膏结晶形态最好,呈短柱状,长径比接近1∶1。

关键词：磷石膏 α半水石膏转晶剂蒸压参数

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钢-UHPC组合板群钉效应有限元分析

福州大学学报（自然科学版） 2022年第6期50卷 833-840页

作者：胡文旭陈宝春李聪苏家战黄文金福州大学土木工程学院福建福州350108 桥梁技术创新与风险防治国家级国际联合研究中心福建福州350108 广西大学土木建筑工程学院广西南宁530004 福建农林大学交通与土木工程学院福建福州350108

建立考虑栓钉焊缝影响的钢-UHPC组合板推出试件的精细化有限元模型,在验证模型有效性和合理性的基础上,深入分析栓钉与UHPC相互作用机理与试件的受力全过程行为,探究栓钉间距对其抗剪性能的影响.有限元分析结果表明:与无焊缝模型相比,... 详细信息

建立考虑栓钉焊缝影响的钢-UHPC组合板推出试件的精细化有限元模型,在验证模型有效性和合理性的基础上,深入分析栓钉与UHPC相互作用机理与试件的受力全过程行为,探究栓钉间距对其抗剪性能的影响.有限元分析结果表明:与无焊缝模型相比,有焊缝模型中的栓钉抗剪承载力与试验值更接近,因此有限元模型中应考虑焊缝的影响;直径和间距对栓钉承载力同样影响显著,且随着栓钉直径增大和间距减小,UHPC板会出现开裂甚至可能破坏.以水平抗剪时栓钉先于UHPC破坏为原则,建议直径d为13 mm的栓钉,其间距不宜小于2.5 d;直径d为16和19 mm的栓钉,其间距不宜小于3.5 d.对于栓钉承载力考虑群钉效应的折减系数η_(G),建议当间距不小于8.0 d时,可取为1.0(不考虑群钉效应);当间距大于建议的最小值且小于8.0 d时,取0.94.

关键词：超高性能混凝土栓钉有限元分析抗剪性能焊缝群钉效应