Metal-free visible-light-induced oxidative cyclization reaction of 1,6-enynes and arylsulfinic acids leading to sulfonylated benzofurans
作者：
Wang, Leilei;Zhang, Min;Zhang, Yulong;Liu, Qishun;Zhao, Xiaohui* ;...
期刊：
中国化学快报(英文) ,2020年31(1):67-70 ISSN：1001-8417
通讯作者：
Wei, Wei;Zhao, Xiaohui
作者机构：
[Zhang, Yulong; Wei, Wei; Wang, Leilei; Liu, Qishun; Zhang, Min] Qufu Normal Univ, Sch Chem & Chem Engn, Qufu 273165, Shandong, Peoples R China.;[Zhao, Xiaohui; Wei, W; Wei, Wei] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Tibetan Med Res, Xining 810008, Qinghai, Peoples R China.;[Zhao, Xiaohui; Wei, W; Wei, Wei] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Tibetan Med Res, Xining 810008, Qinghai, Peoples R China.;[Li, Jiang-Sheng] Changsha Univ Sci & Technol, Sch Chem & Food Engn, Changsha 410114, Peoples R China.;[Luo, Zidan] Hunan Univ Sci & Technol, Sch Chem & Chem Engn, Xiangtan 411201, Peoples R China.
通讯机构：
[Wei, Wei] Q;[Zhao, XH; Wei, W] C;Qufu Normal Univ, Sch Chem & Chem Engn, Qufu 273165, Shandong, Peoples R China.;Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Tibetan Med Res, Xining 810008, Qinghai, Peoples R China.;Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Tibetan Med Res, Xining 810008, Qinghai, Peoples R China.
关键词：
Metal-free;Visible-light-catalysis;1,6-Enynes;Oxidative cyclization;Sulfonylated benzofurans
摘要：
A new and convenient visible-light-induced method has been developed for the synthesis of sulfonylated benzofurans via oxidative cyclization reaction of 1,6-enynes and arylsulfinic acids.This reaction was carried out under metal-free and mild conditions,in which the C-S,C-C and C=O bonds could be sequentially formed in one pot operation.
语种：
英文
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Reliability evaluation of reinforced concrete columns designed by Eurocode for wind-dominated combination considering random loads eccentricity
作者：
Jiang, Youbao* ;Peng, Suixiang;Beer, Michael;Wang, Lei;Zhang, Jianren
期刊：
Advances in Structural Engineering ,2020年23(1):146-159 ISSN：1369-4332
通讯作者：
Jiang, Youbao
作者机构：
[Jiang, Youbao; Peng, Suixiang; Wang, Lei; Zhang, Jianren] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Hunan, Peoples R China;[Beer, Michael] Leibniz Univ Hannover, Inst Risk & Reliabil, Hannover, Germany;[Beer, Michael] Univ Liverpool, Inst Risk & Uncertainty, Liverpool, Merseyside, England
通讯机构：
[Jiang, Youbao] C;Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Hunan, Peoples R China.
关键词：
contribution analysis;Eurocode-based design;random loads eccentricity;reinforced concrete columns;reliability evaluation;wind-dominated combination
摘要：
With the capacity models in the 2004 edition of the European Committee for Standardization's Standard Design of Concrete Structures, a more realistic limit state function is obtained for reinforced concrete columns with random loads eccentricity. Using this function, the applicability of the code-based design factors is discussed. Taking the wind-dominated combination as an example, the probabilistic distribution of loads eccentricity and the statistics of column resistance are analyzed for representative cases. The analysis indicates that the possible loads eccentricity is scattered over a large range, and the probabilistic model of column resistance varies from case to case, which is largely different from the resistance model assumed in previous reliability calibration. With Monte Carlo simulation, the column reliability and the contributions of both tension failure and compression failure to the total failure probability are calculated and obtained for different cases. The results show that the fixed loads eccentricity criterion underestimates differences in the reliability of columns for different loads eccentricity cases and overestimates the column reliability in some tension failure cases. Furthermore, it is found that the tension failure mode contributes most to the total failure probability for not only some columns designed to fail in tension failure but also for some columns designed to fail in compression failure. To attain a robust design, a group of optimum wind load factors varying with cases is recommended. The new calibration results prove that the recommended wind local factors can achieve a better goal.
语种：
英文
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Metal-free I2O5-mediated oxidative synthesis of sulfonylated benzofurans through cyclization reaction of 1,6-enynes and arylsulfonylhydrazides
作者：
Wang, Leilei;Zhang, Yulong;Zhang, Min;Bao, Pengli;Lv, Xiaoxia;...
期刊：
Tetrahedron Letters ,2019年60(28):1845-1848 ISSN：0040-4039
通讯作者：
Wei, Wei;Zhao, Xiaohui
作者机构：
[Zhang, Yulong; Lv, Xiaoxia; Bao, Pengli; Wei, Wei; Wang, Leilei; Zhang, Min] Qufu Normal Univ, Sch Chem & Chem Engn, Qufu 273165, Shandong, Peoples R China.;[Liu, Hai-Gang] Chem Design & Res Inst Qinghai Prov, Xining 810008, Qinghai, Peoples R China.;[Zhao, Xiaohui] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Tibetan Med Res, Xining 810008, Qinghai, Peoples R China.;[Zhao, Xiaohui] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Tibetan Med Res, Xining 810008, Qinghai, Peoples R China.;[Li, Jiang-Sheng] Changsha Univ Sci & Technol, Sch Chem & Food Engn, Changsha 410114, Hunan, Peoples R China.
通讯机构：
[Wei, Wei] Q;[Zhao, Xiaohui] C;Qufu Normal Univ, Sch Chem & Chem Engn, Qufu 273165, Shandong, Peoples R China.;Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Tibetan Med Res, Xining 810008, Qinghai, Peoples R China.;Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Tibetan Med Res, Xining 810008, Qinghai, Peoples R China.
关键词：
1,6-Enynes;Oxidative cyclization;Sulfonylated benzofurans;Sulfonylhydrazides
摘要：
A simple I2O5-mediated method for the construction of sulfonylated benzofurans has been developed under metal-free conditions. The present reaction can be efficiently achieved through the oxidative cyclization of 1,6-enynes and arylsulfonylhydrazides, which provides an attractive approach to a series of sulfonylated benzofurans in moderate to good yields. (C) 2019 Elsevier Ltd. All rights reserved.
语种：
英文
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Crack Detection of FRP-Reinforced Concrete Beam Using Embedded Piezoceramic Smart Aggregates
作者：
Jiang, Tianyong* ;Hong, Yue;Zheng, Junbo;Wang, Lei;Gu, Haichang*
期刊：
Sensors ,2019年19(9):1979 ISSN：1424-8220
通讯作者：
Jiang, Tianyong;Gu, Haichang
作者机构：
[Wang, Lei; Hong, Yue; Jiang, Tianyong] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Hunan, Peoples R China.;[Zheng, Junbo] Cent Southern Safety & Environm Technol Inst Co L, Wuhan 430051, Hubei, Peoples R China.;[Gu, Haichang] Univ Houston, Dept Mech Engn, Houston, TX 77204 USA.
通讯机构：
[Jiang, Tianyong] C;[Gu, Haichang] U;Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Hunan, Peoples R China.;Univ Houston, Dept Mech Engn, Houston, TX 77204 USA.
关键词：
concrete crack damage;fiber-reinforced polymer (FRP) reinforced concrete beam;piezoceramic transducer;smart aggregates (SAs);wavelet packet energy
摘要：
In this paper, the authors present a stress wave-based active sensing method to detect the crack in FRP-reinforced concrete beams. The embedded smart aggregates (SAs), which utilize Lead Zirconate Titanate (PZT) as transducers, are employed in this research to generate and sense the stress wave. Three specimens are involved in the experimental program and each is made of concrete, longitudinal distributed reinforcement, steel stirrups, main bar (FRP bar or steel bar), and four SAs. A pair of SAs installed on the lower part of the main bar and the other pair of SAs mounted on the upper part of main bar are utilized to monitor the crack occurrence and development in the three test specimens. The signals received by the SA sensors are analyzed in both time domain and frequency domain. The wavelet packet energy is used to extract damage features. The applied load-vertical displacement curves of mid-span in the specimen are obtained. Experimental results show the test specimens experience crushing failure when the concrete compression exceeds its compressive strength. Increasing the contact area between FRP bar and concrete can effectively improve the cracking load of the FRP-reinforced concrete beam and reduce the cracking speed and depth of FRP-reinforced concrete beam; on the other hand, increasing the elastic modulus of the main bar can slow down the crack development of concrete on the upper side of the main bar and decrease the displacement of reinforced concrete beam during the loading test process. The research results show that the developed piezoceramic-based active sensing method, though low-cost, can monitor the crack-induced damage and estimate the process of damage degree in real-time, and has potentials to provide an early warning of crack occurrence and development for FRP-reinforced concrete beams.
语种：
英文
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锈蚀钢筋混凝土梁斜截面抗剪失效分析
作者：
马亚飞;刘彬;王磊;张建仁
期刊：
长安大学学报(自然科学版) ,2019年39(1):90-98 ISSN：1671-8879
作者机构：
长沙理工大学土木工程学院,湖南长沙,410114;[马亚飞; 刘彬; 张建仁; 王磊] 长沙理工大学
关键词：
桥梁工程;钢筋混凝土梁;斜筋;箍筋;锈蚀;抗剪性能
摘要：
为了研究锈蚀对钢筋混凝土构件抗剪性能的影响,设计并制作了7根配有箍筋和斜筋的钢筋混凝土矩形梁,其中1根为未锈蚀的对比梁,采用电化学快速锈蚀方法对其余6根钢筋混凝土梁进行加速锈蚀试验。开展相同剪跨比下钢筋混凝土梁的斜截面抗剪性能试验,讨论钢筋混凝土梁表面初始锈胀裂缝的分布特征,分析箍筋锈蚀、斜筋锈蚀和主筋锈蚀对钢筋混凝土梁斜裂缝的形成与发展、荷载-挠度曲线、剪压区混凝土压力传递过程以及钢筋的内力变化情况,研究不同锈蚀程度钢筋混凝土梁斜截面极限承载能力与失效特征。研究结果表明:弯剪斜裂缝的数量随着钢筋锈蚀水平的增长逐渐减少,斜裂缝的延伸长度变短,主拱传递压应力路径逐步由直线变为抛物线形;锈胀引起的剪压区混凝土截面损伤对钢筋混凝土构件的抗剪强度有很大影响;箍筋锈蚀和斜筋锈蚀对斜裂缝的发展影响较大,而对钢筋混凝土梁的破坏形态影响相对较小,但其截面面积的减小会导致箍筋和斜筋过早的发生断裂,进而降低钢筋混凝土梁的斜截面抗剪强度;随着主筋锈蚀程度的增长,临界斜裂缝的倾角变大,并且与仅箍筋锈蚀梁相比,其倾角增幅更为显著。该研究可为钢筋混凝土梁的抗剪强度预测模型的建立以及有限元分析提供试验基础。
语种：
中文
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Synthesis and photocatalytic property of V2O5@TiO2 core-shell microspheres towards gaseous benzene
作者：
Li, Yangfan;Wang, Linlin;Li, Zhaolong;Liu, Yueli* ;Peng, Zhuoyin* ;...
期刊：
Catalysis Today ,2019年321:164-171 ISSN：0920-5861
通讯作者：
Liu, Yueli;Peng, Zhuoyin
作者机构：
[Wang, Linlin; Zhou, Min; Zhang, Chao; Li, Zhaolong; Liu, Yueli; Li, Yangfan; Jin, Wei] Wuhan Univ Technol, Sch Mat Sci & Engn, State Key Lab Silicate Mat Architectures, Wuhan 430070, Hubei, Peoples R China.;[Peng, Zhuoyin; Li, Zhaolong] Changsha Univ Sci & Technol, Sch Energy & Power Engn, Key Lab Efficient & Clean Energy Utilizat, Changsha 410111, Hunan, Peoples R China.
通讯机构：
[Liu, Yueli] W;[Peng, Zhuoyin] C;Wuhan Univ Technol, Sch Mat Sci & Engn, State Key Lab Silicate Mat Architectures, Wuhan 430070, Hubei, Peoples R China.;Changsha Univ Sci & Technol, Sch Energy & Power Engn, Key Lab Efficient & Clean Energy Utilizat, Changsha 410111, Hunan, Peoples R China.
关键词：
Charge recombination;Gaseous benzene;Photocatalytic performance;V2O5@TiO2 core-shell microspheres
摘要：
In the present work, V2O5 microspheres with the diameters ranging from 1 to 2 μm are prepared by a facile hydrothermal progress, and then V2O5@TiO2 core-shell microspheres are successfully synthesized by a solution method. It is found that the light absorption intensity of V2O5@TiO2 core-shell microspheres is greatly enhanced compared with those of V2O5 microspheres and P25 in UV and visible light ranges. The photodegradation rate towards gaseous benzene of V2O5@TiO2-20% core-shell microspheres is the best one, and it will increase from 27.8% and 10% (pure V2O5 microspheres) to be 100% and 71.8% after 75 min’ irradiation under UV and visible light irradiation, respectively. The reason lies in the fact that the formation of V2O5@TiO2 core-shell microspheres may favor for the light absorption as well as the effective separation of the photoexcited electrons and holes. © 2018 Elsevier B.V.
语种：
英文
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Shrinkage behavior influence of strain-hardening cementitious composites
作者：
Zhang, Yongxing;Fang, Yong;Lu, Weihua;Liu, Cheng;Wang, Lei;...
期刊：
Structural Concrete ,2019年20(6):2150-2155 ISSN：1464-4177
通讯作者：
Zhang, Xuemin
作者机构：
[Lu, Weihua; Zhang, Yongxing; Liu, Cheng] Nanjing Forestry Univ, Sch Civil Engn, Nanjing, Peoples R China.;[Zhang, Yongxing; Fang, Yong] Southwest Jiaotong Univ, Minist Educ, Key Lab Transportat Tunnel Engn, Chengdu, Peoples R China.;[Zhang, Yongxing] Guangxi Univ, Minist Educ, Key Lab Disaster Prevent & Struct Safety, Guangxi Key Lab Disaster Prevent & Engn Safety, Nanning, Peoples R China.;[Wang, Lei; Xie, Haibo] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha, Peoples R China.;[Zhang, Xuemin] Cent South Univ, Sch Civil Engn, 68 South Shaoshan Rd, Changsha 410075, Peoples R China.
通讯机构：
[Zhang, Xuemin] C;Cent South Univ, Sch Civil Engn, 68 South Shaoshan Rd, Changsha 410075, Peoples R China.
关键词：
curing condition;experimental investigation;SHCC;shrinkage behavior;varied ingredients
摘要：
This paper presents an experimental investigation into the shrinkage behavior of strain-hardening cementitious composite (SHCC), which focuses on the influences of varied ingredients in mix proportions and curing condition. The experimental results confirm that the shrinkage strains of SHCC are obviously influenced by the investigated ingredients of SHCC, in which expansion agent can induce expansion strain for nominally reducing the shrinkage strains of SHCC, the shrinkage strains of SHCC's matrix are decreased with increasing fiber volume content and water-to-binder ratio, whereas those are increased with increasing silica-fume-to-binder ratio. Moreover, the curing condition has significant influence for the shrinkage behavior of SHCC, and water curing can significantly reduce the shrinkage strains. This work provides experimental foundations for shrinkage behavior of SHCC. © 2019 fib. International Federation for Structural Concrete
语种：
英文
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Modelling guidelines for corrosion-fatigue life prediction of concrete bridges: Considering corrosion pit as a notch or crack
作者：
Guo, Zhongzhao;Ma, Yafei* ;Wang, Lei;Zhang, Jianren
期刊：
Engineering Failure Analysis ,2019年105:883-895 ISSN：1350-6307
通讯作者：
Ma, Yafei
作者机构：
[Ma, Yafei; Wang, Lei; Zhang, Jianren; Guo, Zhongzhao] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Hunan, Peoples R China.
通讯机构：
[Ma, Yafei] C;Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Hunan, Peoples R China.
关键词：
Bridge engineering;Fatigue crack growth;Pitting corrosion;Probabilistic method;Stress concentration
摘要：
Corrosion accelerates the fatigue damage accumulation and decreases the fatigue life of reinforced concrete bridges. A critical issue in the corrosion-fatigue life prediction is to deal with the relationship between fatigue crack and corrosion propagation. This paper proposes two modelling methods for fatigue life prediction of reinforced concrete bridges subjected to coupled corrosion-fatigue effect: model I considers the corrosion pit as a notch and model II treats the corrosion pit as a surface crack. The chloride ingress, cyclic load, corrosion pit growth, fatigue crack growth and concrete severe cracking are systematically considered. Following that, a probabilistic analysis is also performed to include various uncertainties in the two models, and the effects of environment aggressiveness level and traffic frequency on the prediction results are investigated. The results show that corrosion pit-induced stress concentration has a significant effect on the fatigue behavior, and modelling the corrosion pit as a notch is the preferred method for theoretical prediction. For the extreme aggressiveness environment and low traffic frequency conditions, considering the corrosion pit as a crack is an alternative modelling method for the fast assessment of aging reinforced concrete bridges due to its simplicity. © 2019 Elsevier Ltd
语种：
英文
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Catalyst-free visible-light-initiated oxidative coupling of aryldiazo sulfones with thiols leading to unsymmetrical sulfoxides in air
作者：
Liu, Qishun;Wang, Leilei;Yue, Huilan;Li, Jiang-Sheng;Luo, Zidan;...
期刊：
Green Chemistry ,2019年21(7):1609-1613 ISSN：1463-9262
通讯作者：
Wei, Wei
作者机构：
[Wei, Wei; Wang, Leilei; Liu, Qishun] Qufu Normal Univ, Sch Chem & Chem Engn, Qufu 273165, Shandong, Peoples R China.;[Yue, Huilan; Wei, Wei] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Tibetan Med Res, Xining 810008, Qinghai, Peoples R China.;[Yue, Huilan; Wei, Wei] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Tibetan Med Res, Xining 810008, Qinghai, Peoples R China.;[Li, Jiang-Sheng] Changsha Univ Sci & Technol, Sch Chem & food Engn, Changsha 410114, Hunan, Peoples R China.;[Luo, Zidan] Hunan Univ Sci & Technol, Sch Chem & Chem Engn, Xiangtan 411201, Peoples R China.
通讯机构：
[Wei, Wei] Q;[Wei, Wei] C;Qufu Normal Univ, Sch Chem & Chem Engn, Qufu 273165, Shandong, Peoples R China.;Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Tibetan Med Res, Xining 810008, Qinghai, Peoples R China.;Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Tibetan Med Res, Xining 810008, Qinghai, Peoples R China.
摘要：
A facile and efficient visible-light-driven method has been developed to construct sulfoxides via oxidative coupling of aryldiazo sulfones with thiols using the O2 in air as the oxidant. This reaction could be performed at room temperature under catalyst- and additive-free conditions. The present methodology offers a mild and environmentally benign approach to obtain a library of sulfoxides in good yields with favorable functional group tolerance. © 2019 The Royal Society of Chemistry.
语种：
英文
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BiVO4@TiO2 core-shell hybrid mesoporous nanofibers towards efficient visible-light-driven photocatalytic hydrogen production
作者：
Hou, Huilin;Wang, Lin;Gao, Fengmei;Yang, Xianfeng;Yang, Weiyou*
期刊：
Journal of Materials Chemistry C ,2019年7(26):7858-7864 ISSN：2050-7526
通讯作者：
Yang, Weiyou
作者机构：
[Gao, Fengmei; Wang, Lin; Yang, Weiyou; Hou, Huilin] Ningbo Univ Technol, Inst Mat, Ningbo 315016, Zhejiang, Peoples R China.;[Yang, Xianfeng] Changsha Univ Sci & Technol, Coll Phys & Elect Sci, Changsha 410114, Hunan, Peoples R China.
通讯机构：
[Yang, Weiyou] N;Ningbo Univ Technol, Inst Mat, Ningbo 315016, Zhejiang, Peoples R China.
关键词：
Atomic layer deposition;Bismuth compounds;Heterojunctions;Hydrogen production;Light;Nanofibers;Photocatalytic activity;Semiconducting bismuth compounds;Shells (structures);Surface reactions;Titanium dioxide;Charge separations;Core shell structure;Core-shell hybrids;High specific surface area;Photocatalytic hydrogen production;Reduction level;Visible irradiation;Visible-light-driven;Vanadium compounds
摘要：
The conduction band of a BiVO4 semiconductor is slightly lower than the hydrogen (H2) reduction level, indicating that it can't be used directly for visible-light-driven photocatalytic hydrogen production. In the present work, we report designed BiVO4@TiO2 core-shell hybrid mesoporous nanofibers for photocatalytic hydrogen production under visible irradiation, which are generated through foaming-assisted electrospinning followed by atomic layer deposition (ALD). Such a binary core-shell structure can not only provide a high specific surface area with increased reaction sites, but also cause the formation of a staggered BiVO4@TiO2 heterojunction to promote the charge separation and transfer, leading to a significantly enhanced photocatalytic H2 production efficiency as compared to pure BiVO4. © 2019 The Royal Society of Chemistry.
语种：
英文
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Autonomous Resource Request Transaction Framework Based on Blockchain in Social Network
作者：
Gu, Ke* ;Wang, Linyu;Jia, Weijia
期刊：
IEEE ACCESS ,2019年7(99):43666-43678 ISSN：2169-3536
通讯作者：
Gu, Ke
作者机构：
[Gu, Ke] Changsha Univ Sci & Technol, Sch Comp & Commun Engn, Changsha 410114, Hunan, Peoples R China.;[Wang, Linyu] Hunan Inst Informat Technol, Sch Elect Informat, Changsha 410151, Hunan, Peoples R China.;[Jia, Weijia] Univ Macau, Dept Comp & Informat Sci, Macau 999078, Peoples R China.
通讯机构：
[Gu, Ke] C;Changsha Univ Sci & Technol, Sch Comp & Commun Engn, Changsha 410114, Hunan, Peoples R China.
关键词：
blockchain;community;Resource request;social network;transaction
摘要：
Currently, blockchain technology has been widely researched and is being applied to many other fields, such as financial transactions, E-government, logistics, and supply-chain system. It can be used to store and maintain transaction data through the de-centralized model. In this paper, we propose an autonomous resource request transaction framework based on blockchain in a social network, in which all kinds of resources in the social community can be traded through blockchain technology. When a user needs to acquire some resources from a community, the user may make a transaction with the members from the community through blockchain technology while the members autonomously negotiate each other to reach an agreement. The proposed framework provides an incentive mechanism to encourage community members to disseminate the resources through a smart contract.
语种：
英文
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基于EIC增长的锈蚀钢筋混凝土梁疲劳寿命评估
作者：
马亚飞;王磊;张建仁
期刊：
公路交通科技 ,2019年36(4):80-87 ISSN：1002-0268
作者机构：
长沙理工大学 土木工程学院,湖南 长沙,410114;[马亚飞; 张建仁; 王磊] 长沙理工大学
关键词：
桥梁工程;疲劳;等效初始裂纹原理;锈蚀;裂纹扩展
摘要：
锈蚀和疲劳荷载共同影响下的材料复合损伤机理十分复杂,会显著降低既有钢筋混凝土桥梁的使用寿命。为了能够准确地预测锈蚀钢筋混凝土梁的疲劳寿命,通过从材料到钢筋混凝土构件的跨尺度分析,提出了一种基于材料失效机理的锈蚀钢筋混凝土梁疲劳寿命评估方法。该方法以断裂力学和等效初始裂纹理论为基础,并且可以同时考虑钢筋的不同锈蚀形态。结合锈蚀钢筋的疲劳拉伸试验结果,提出了不同锈蚀水平下的应力集中因子表达式,结果表明随锈蚀率的增长,应力集中因子先增大后减小。然后将局部锈蚀导致的应力集中的影响融入到应力强度因子计算模型中;通过对试验数据进行拟合得到了钢筋疲劳裂纹速率增长分析模型,对该模型从等效初始裂纹尺寸到临界裂纹长度进行积分来实现钢筋混凝土梁的疲劳寿命预测。为了验证本评估方法的有效性,开展了电化学快速锈蚀钢筋混凝土梁的疲劳性能试验,试验梁失效形式均为受力主筋的疲劳断裂;采用扫描电子显微镜对疲劳失效后的锈蚀钢筋断口形貌进行了微观分析,对比了不同锈蚀程度下钢筋疲劳裂纹扩展形式的差异。将理论计算结果与本研究试验和已有文献中的试验值进行了比较,二者吻合较好,可为日后钢筋混凝土桥梁的腐蚀疲劳寿命评估提供科学依据。
语种：
中文
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Interface Debonding Detection of Precast Segmental Concrete Beams (PSCBs) Using Piezoceramic Transducer-Based Active Sensing Approach
作者：
Liu, Yang;Zhang, Ming;Yin, Xinfeng* ;Hei, Chuang;Wang, Lei
期刊：
Mathematical Problems in Engineering ,2019年2019:1-11 ISSN：1024-123X
通讯作者：
Yin, Xinfeng
作者机构：
[Yin, Xinfeng; Wang, Lei; Liu, Yang; Zhang, Ming] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Hunan, Peoples R China.;[Hei, Chuang] Univ Houston, Dept Mech Engn, Houston, TX 77204 USA.
通讯机构：
[Yin, Xinfeng] C;Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Hunan, Peoples R China.
关键词：
Adhesives;Concrete aggregates;Damage detection;Debonding;Epoxy resins;Frequency domain analysis;Piezoelectric ceramics;Precast concrete;Time domain analysis;Transducers;Actuators and sensors;Concrete specimens;Debonding damage;Experimental research;Interface debonding;Piezoceramic sensors;Piezoceramic transducer;Smart aggregates;Concrete beams and girders
摘要：
An active sensing approach using piezoceramic induced stress wave is proposed to provide monitoring and early warning for the development of interface debonding damage of precast segmental concrete beams (PSCBs). Three concrete specimens with toothed interfaces were fabricated and bonded with high-strength epoxy resin adhesive to form PSCBs. Smart aggregates (SAs) embedded in concrete specimens are used as actuators and sensors. The PSCBs are subjected to periodic loading with hydraulic jack to test the different degrees of debonding damage. The experimental results of time-domain and frequency-domain analysis clearly show that the amplitude of the signal received by the piezoceramic sensor is reduced when debonding crack occurs. The energy analysis and damage index based on wavelet packet can be used to determine the existence and severity of interface debonding damage in PSCBs. The experimental research validates the feasibility of monitoring the interface debonding damage in PSCBs using SA transducers based on active sensing technique. © 2019 Yang Liu et al.
语种：
英文
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Flexural behavior of corroded HPS beams
作者：
Peng, Jianxin;Xiao, Linfa* ;Zhang, Jianren;Cai, C. S.;Wang, Lei
期刊：
Engineering Structures ,2019年195:274-287 ISSN：0141-0296
通讯作者：
Xiao, Linfa
作者机构：
[Xiao, Linfa; Peng, Jianxin; Wang, Lei; Zhang, Jianren] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Hunan, Peoples R China.;[Cai, C. S.] Louisiana State Univ, Dept Civil & Environm Engn, Baton Rouge, LA 70803 USA.
通讯机构：
[Xiao, Linfa] C;Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Hunan, Peoples R China.
关键词：
3D scanning technology;Analytical model;Flexural behavior;High performance steel (HPS);Random corrosion
摘要：
Experimental research is conducted to investigate the flexural behavior of corroded High Performance Steel (HPS) beams. Four beams with various corrosion damage are designed and subjected to electrochemical accelerated corrosion process. 3D scanning technology is employed to analyze the geometric features affected by the corrosion damage. Flexural tests are carried out, and the impact of corrosion on the flexural response is discussed. Considering the randomness of corrosion pits in each area, predictive models are proposed for the flexural strength of corroded beams with an idealized elastic-plastic and linear-hardening constitutive relationship model. An analysis comparing the proposed models with Chinese and American codes is made. Results show that increasing the corrosion damage leads to a decrease of discreteness in the residual sectional area and causes a transformation in the compressed flange from noncompact to slender. A corrosion loss less than 10% leads to slight deterioration of both strength and stiffness degradation, while further corrosion damage results in a significant decrease. The depth and length of the buckling wavelength for corroded beams decreases gradually as the corrosion damage become more serious. The analytical models IEM and LHM or the GB50017-2017 may be suitable for predicting the lower and upper limit values of the ultimate flexural moment, respectively, and results predicted by AISC are conservative. © 2019 Elsevier Ltd
语种：
英文
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Electrocatalytic activity of MnO2 nanosheet array-decorated carbon paper as superior negative electrode for vanadium redox flow batteries
作者：
Jiang, Yingqiao;Feng, Xiaojian;Cheng, Gang;Li, Yuehua;Li, Chuanchang;...
期刊：
Electrochimica Acta ,2019年322:134754 ISSN：0013-4686
通讯作者：
He, Zhangxing;Dai, Lei;Wang, Ling
作者机构：
[He, ZX; Dai, L; Wang, L; Feng, Xiaojian; Jiang, Yingqiao; Dai, Lei; Li, Yuehua; Zhou, Huizhu; Cheng, Gang; He, Zhangxing; Zhu, Jing; Meng, Wei; Wang, Ling] North China Univ Sci & Technol, Sch Chem Engn, Tangshan 063009, Peoples R China.;[Li, Chuanchang; He, Zhangxing] Changsha Univ Sci & Technol, Sch Energy & Power Engn, Changsha 410114, Hunan, Peoples R China.;[Dai, Lei; He, Zhangxing; Wang, Ling] North China Univ Sci & Technol, Hebei Prov Key Lab Photocatalyt & Electrocatalyt, Tangshan 063009, Peoples R China.
通讯机构：
[He, ZX; Dai, L; Wang, L] N;North China Univ Sci & Technol, Sch Chem Engn, Tangshan 063009, Peoples R China.
关键词：
Energy storage;Vanadium redox flow batteries;Carbon paper;MnO2 nanosheets;Electrochemical kinetics
摘要：
An in-situ and controllable redox deposition method has been applied to prepare binder-free MnO2 nanosheet array-decorated carbon paper as negative electrode for vanadium redox flow batteries (VRFB). Electrochemical performance of electrode depends on amount and uniform distribution of MnO2 on carbon paper, which were controlled by solution pH, KMnO4 concentration, and deposition time. Modified carbon paper (CPA-05-30) with a uniform MnO2 nanosheet coating layer was obtained in 0.05 M KMnO4 + 0.5 M H2SO4 solution for 30 min. CPA-05-30 presents the most excellent electrocatalytic performance for V3+/V2+ redox reaction. On CPA-05-30, charge transfer and diffusion processes for V3+/V2+ redox reaction are accelerated as a result of MnO2 nanosheet with high catalytic activity and excellent hydrophilcity. Therefore, loading MnO2 on carbon paper improves electrochemical activity V3+/V2+ redox reaction. Moreover, in charge-discharge test, the cell using CPA-05-30 as negative electrode shows higher discharge capacity and better capacity retention at 50 mA cm(-2) for 50 cycles in comparison with pristine cell. It indicates that MnO2 nanosheet can efficiently increase electrolyte utilization. At 100 mA cm(-2), energy efficiency of the cell using CPA-05-30 is 66.4%, which is 6.0% higher than that of pristine cell. MnO2 nanosheet decorated carbon paper shows excellent electrochemical properties for energy storage application, which evidences its potential application in VRFB. (C) 2019 Elsevier Ltd. All rights reserved.
语种：
英文
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Phosphorization-Induced Void-Containing Fe3O4 Nanoparticles Enabling Low Lithiation/Delithiation Potential for High-Performance Lithium-Ion Batteries
作者：
Nie, Yan;Zhang, Hang;Zhang, Jinfeng;Wang, Lei;Zhong, Siyu;...
期刊：
ChemElectroChem ,2019年6(19):5060-5069 ISSN：2196-0216
通讯作者：
Zhang, Guanhua
作者机构：
[Zhang, Guanhua; Duan, Huigao; Zhang, Jinfeng; Victor, Kipkoech Kirui; Nie, Yan; Wang, Lei; Zhong, Siyu] Hunan Univ, Coll Mech & Vehicle Engn, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.;[Zhang, Hang] Shaanxi Normal Univ, Sch Chem & Chem Engn, Minist Educ, Key Lab Appl Surface & Colloid Chem, Xian 710119, Shaanxi, Peoples R China.;[Duan, Junfei; Wu, Yinglong] Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410004, Hunan, Peoples R China.;[Shi, Huimin] Guangzhou Univ, Sch Mech & Elect Engn, Ctr Res Leading Technol Special Equipment, Guangzhou 510006, Guangdong, Peoples R China.
通讯机构：
[Zhang, Guanhua] H;Hunan Univ, Coll Mech & Vehicle Engn, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.
关键词：
lithium-ion batteries;anodes;low lithiation;delithiation potential;phosphorization;Fe3O4
摘要：
<jats:title>Abstract</jats:title><jats:p>In terms of Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub>‐based anodes, enormous academic progress has been achieved over the past two decades; however, even with excellent half‐cell performance, the relatively high lithiation potential and unsatisfactory initial coulombic efficiency (ICE) represent two major barriers to their commercial application, at present. We propose partially phosphorized Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub> (P−Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub>) with interior void spaces induced by phosphorization to enhance the Li<jats:sup>+</jats:sup> storage property of Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub>‐based anodes. P−Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub> anodes offer a much higher capacity at low potential compared with bare Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub> electrodes. Additionally, the well‐designed nanostructure with preferable specific surface area prevents the initial irreversible lithium loss, which contributes to a brilliant ICE (80.8 % at 100 mA g<jats:sup>−1</jats:sup>). Moreover, in‐situ X‐ray diffraction proves that the formation of the Li<jats:sub><jats:italic>x</jats:italic></jats:sub>Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub> phase results from an initial intercalation process. In particular, the output voltage and energy density of P−Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub> full‐cells are much greater than those of Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub> full‐cells. In this work, the P−Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub> full‐cell exhibits a capacity of 680 mAh g<jats:sup>−1</jats:sup> at 200 mA g<jats:sup>−1</jats:sup> as well as an excellent rate capability of 267 mAh g<jats:sup>−1</jats:sup> with a current density up to 1000 mA g<jats:sup>−1</jats:sup>. This study presents a new strategy to enhance Li<jats:sup>+</jats:sup> storage of Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub> enabling low lithiation/delithiation potential and high ICE, which may offer exciting opportunities toward designing high‐performance full‐cells with commercial cathodes.</jats:p>
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英文
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腐蚀预应力混凝土桥梁抗力退化预测方法
作者：
邹向农;龙俊贤;陈宇翔;马亚飞;王磊
期刊：
中外公路 ,2019年39(3):84-89 ISSN：1671-2579
作者机构：
中铁大桥勘测设计院集团有限公司,湖北武汉,430050;[马亚飞; 陈宇翔; 王磊] 长沙理工大学;[龙俊贤; 邹向农] 中铁大桥勘测设计院
关键词：
桥梁工程;预应力混凝土;锈蚀;抗力退化;概率方法
摘要：
针对氯盐环境下预应力混凝土桥梁中钢绞线锈蚀引起的抗力退化问题,以一座服役预应力混凝土桥梁为例,考虑钢绞线锈蚀初始和发展过程、锈蚀导致的钢绞线截面积减小、钢绞线强度降低以及钢绞线与混凝土间的黏结性退化,采用Monte Carlo数值模拟方法,建立了锈蚀预应力混凝土桥梁构件抗力退化预测概率模型,分析了锈蚀对预应力混凝土桥梁构件抗力水平的影响。研究结果表明:钢绞线锈蚀开始阶段,坑深增长较快,且各个蚀坑的差值较小;随锈蚀的发展,坑深增长逐渐变缓。锈蚀初始时间服从对数正态分布,不同时刻抗力可用正态分布来表征。
语种：
中文
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悬索桥主索鞍超量顶推施工控制分析
作者：
王达;汪威;王磊
期刊：
交通科学与工程 ,2019年35(01):32-37 ISSN：1674-599X
作者机构：
长沙理工大学 土木工程学院,湖南 长沙,410114;[王达; 汪威; 王磊] 长沙理工大学
关键词：
悬索桥;主索鞍顶推;位移;应力;超量顶推
摘要：
为精确模拟悬索桥主索鞍在施工中的变化情况,采用空间有限元法,同时考虑结构非线性影响,并通过对比现场实测数据,验证了本研究空间有限元法的合理性。以水云桥为工程背景,建立全桥有限元模型,模拟实际施工过程,对比分析了主索鞍常规顶推、主索鞍不顶推及主索鞍自由滑动3种施工方案分别对应的结构变位和受力状态,得出主索鞍超量顶推的优化施工方案。工程应用结果表明:主索鞍超量顶推不仅能确保结构线形和受力,满足现场施工要求,还具备较高的施工控制精度。
语种：
中文
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Reactive synthesis and assessment of porous Fe-20.5Al-18Cr intermetallic material: A comparative study with porous FeCrAl material produced from prealloyed powders
作者：
Zhang, Huibin;Gao, Haiyan;Liu, Xinli;Yu, Hang;Wang, Longfei;...
期刊：
Separation and Purification Technology ,2019年220:152-161 ISSN：1383-5866
通讯作者：
He, Yuehui
作者机构：
[Zheng, Guoqu; Wang, Longfei; Yu, Hang; Zhang, Huibin] Zhejiang Univ Technol, Coll Mat Sci & Engn, Hangzhou 310014, Zhejiang, Peoples R China.;[Gao, Haiyan; Liu, Xinli; Jiang, Yao; He, Yuehui; Zhang, Huibin] Cent S Univ, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China.;[Liu, Xinli] Cent S Univ, Coll Mat Sci & Engn, Changsha 410083, Hunan, Peoples R China.;[Gao, Lin] Intermet Technol Chengdu Co LTD, Chengdu 611731, Sichuan, Peoples R China.;[Yu, Linping] Changsha Univ Sci & Technol, Sch Chem & Biol Engn, Changsha 410114, Hunan, Peoples R China.
通讯机构：
[He, Yuehui] C;Cent S Univ, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China.
关键词：
Coal gas;FeAl;FeCrAl;Filtration;Intermetallic;Porous material
摘要：
B2-structured Fe-20.5Al-18Cr (wt.%) intermetallic filter material developed for high-temperature coal-gas purification was fabricated by reactive synthesis using blended Fe/Al/Cr powders. This method addresses the problems presented in the manufacture of porous Fe-Al-Cr materials with high content of Al, making the production more convenient, flexible and controllable. The exothermic effect, volume swelling, pore formation and diffusion reactions during the reactive synthesis of porous Fe-20.5Al-18Cr were investigated systematically. A comparative study with porous Fe20Cr7Al material produced from prealloyed powders was carried out synchronously. The results show that during sintering the Fe-20.5Al-18Cr compact presents limited exothermic behavior and obvious volume expansion, and that the abundant pores and compositional homogenization can be obtained through the interactions of Fe/Al/Cr powders after final sintering. As compared with sintered Fe20Cr7Al porous material, porous Fe-20.5Al-18Cr possesses bigger permeability constants and lower oxidation and sulfidation rates. Pilot-scale filtration tests reveal that Fe-20.5Al-18Cr filter material can robustly serve in the corrosive H 2 S-contained and alkali-metals-oxides-loaded high-temperature coal gas during a period of 1000 h. © 2019 Elsevier B.V.
语种：
英文
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Electrospun nitrogen-doped carbon nanofiber as negative electrode for vanadium redox flow battery
作者：
He, Zhangxing;Li, Manman;Li, Yuehua;Wang, Ling* ;Zhu, Jing;...
期刊：
Applied Surface Science ,2019年469:423-430 ISSN：0169-4332
通讯作者：
Wang, Ling;Dai, Lei;Li, Chuanchang
作者机构：
[Dai, Lei; Li, Yuehua; Zhou, Huizhu; Wang, Ling; Dai, L; Li, Manman; He, Zhangxing; Zhu, Jing; Meng, Wei] North China Univ Sci & Technol, Sch Chem Engn, Tangshan 063009, Peoples R China.;[Li, Chuanchang; He, Zhangxing] Changsha Univ Sci & Technol, Educ Dept Hunan Prov, Key Lab Efficient & Clean Energy Utilizat, Changsha 410114, Hunan, Peoples R China.;[Dai, Lei; Wang, Ling; Dai, L; He, Zhangxing] North China Univ Sci & Technol, Hebei Prov Key Lab Photocatalyt & Electrocatalyt, Tangshan 063009, Peoples R China.
通讯机构：
[Wang, L; Dai, L] N;[Li, Chuanchang] C;North China Univ Sci & Technol, Sch Chem Engn, Tangshan 063009, Peoples R China.;Changsha Univ Sci & Technol, Educ Dept Hunan Prov, Key Lab Efficient & Clean Energy Utilizat, Changsha 410114, Hunan, Peoples R China.;North China Univ Sci & Technol, Hebei Prov Key Lab Photocatalyt & Electrocatalyt, Tangshan 063009, Peoples R China.
关键词：
Carbon nanofiber;Electrospinning;Negative electrode;Nitrogen doping;Vanadium redox flow battery
摘要：
Carbon nanofiber (CNF) was developed via electrospinning technique with polyacrylonitrile as precursor. Nitrogen-doped carbon nanofiber (NCNF), synthesized by liquid phase dispersion and carbonization processes with urea at 800–1000 °C, were investigated as negative electrode for vanadium redox flow battery (VRFB). Morphology and structure of CNF and NCNF were systematically investigated by SEM, Raman, XPS, etc. The morphology of CNF is not changed by nitrogen doping. However, nitrogen doping can lead to marked enhancement of surface defect and hydrophilicity. Electrochemical test results show that NCNF treated at 900 °C (CNF-N9) exhibits the best electrochemical performance. The excellent energy storage performance of the cell is obtained by using CNF-N9. Discharge capacity of cell for CNF-N9 arrives at 98.0 mA h, 30.0 mA h higher than that of the pristine cell at 90 mA cm −2 . And energy efficiency of the cell using CNF-N9 increases by 6.3% compared with pristine cell. Outstanding performances of CNF-N9 come from the increase of surface defect and the improvement of hydrophilicity and conductivity resulting from nitrogen doping, further promoting the electron and mass transfer between vanadium ion and electrode. © 2018 Elsevier B.V.
语种：
英文
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