Unlocking the Lithium Storage Capacity of Aluminum by Molecular Immobilization and Purification.
作者：
Xia, Guanglin;Zhang, Hongyu;Liang, Ming;Zhang, Jian;Sun, Weiwei;...
期刊：
Advanced Materials ,2019年31(24):e1901372 ISSN：0935-9648
通讯作者：
Yu, Xuebin
作者机构：
[Fang, Fang; Xia, Guanglin; Sun, Dalin; Yu, Xuebin; Zhang, Hongyu] Fudan Univ, Dept Mat Sci, Shanghai 200433, Peoples R China.;[Liang, Ming; Sun, Weiwei] Shanghai Univ, Sch Environm & Chem Engn, Dept Chem Engn, Shanghai 200444, Peoples R China.;[Zhang, Jian] Changsha Univ Sci & Technol, Hunan Prov Key Lab Safety Design & Reliabil Techn, Changsha 410114, Hunan, Peoples R China.
通讯机构：
[Yu, Xuebin] F;Fudan Univ, Dept Mat Sci, Shanghai 200433, Peoples R China.
关键词：
aluminum;anodes;graphene;lithium-ion batteries;self-assembly
摘要：
Aluminum is regarded as a promising alternative for graphite anode in next-generation lithium-ion batteries, but its application is hindered by the simultaneous presence of aluminum oxide and the huge volume changes. Herein, hydrogenation-induced self-assembly of robust Al nanocrystals with high purity that are uniformly anchored on graphene is demonstrated. The strong molecular interaction between Al and graphene can not only thermodynamically facilitate the homogenous distribution of Al on graphene but also effectively alleviate the volume changes and preserve the structural integrity of the electrode. More importantly, density functional theory calculations reveal that the absence of oxidation can lower the energy barrier for Li diffusion inside the Al matrix to less than 1/6 of that in an Al matrix with only one monolayer coverage of oxygen. These unique structural features enable the aluminum/graphene nanosheets (Al@GNs) electrode to realize a high reversible capacity of 1219 mAh g(-1) and an excellent cycling stability with capacity of 766 mAh g(-1) after 1000 cycles at the 3 A g(-1) rate. Furthermore, a full cell, comprising an Al@GNs anode and LiFePO4 cathode, exhibits remarkable capacity retention of 96.4% after 100 cycles at the 0.5 A g(-1) rate.
语种：
英文
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Synergy Effect of Attapulgite, Rubber, and Diatomite on Organic Montmorillonite-Modified Asphalt
作者：
Jin, Jiao* ;Tan, Yanqing;Liu, Ruohua;Zheng, Jianlong;Zhang, Junhui
期刊：
Journal of Materials in Civil Engineering ,2019年31(2) ISSN：0899-1561
通讯作者：
Jin, Jiao
作者机构：
[Jin, Jiao] Changsha Univ Sci & Technol, Key Lab Special Environm Rd Engn Hunan Prov, Sch Traff & Transportat Engn, Changsha 410114, Hunan, Peoples R China.;[Zhang, Junhui; Zheng, Jianlong; Tan, Yanqing] Changsha Univ Sci & Technol, Sch Traff & Transportat Engn, Changsha 410114, Hunan, Peoples R China.;[Liu, Ruohua] Cent S Univ, Sch Minerals Proc & Bioengn, Changsha 410083, Hunan, Peoples R China.
通讯机构：
[Jin, Jiao] C;Changsha Univ Sci & Technol, Key Lab Special Environm Rd Engn Hunan Prov, Sch Traff & Transportat Engn, Changsha 410114, Hunan, Peoples R China.
关键词：
Montmorillonite;Diatomite;Rubber;Attapulgite;Rheology;Aging
摘要：
Organic montmorillonite (OMMT) was obtained by reacting montmorillonite (MMT) with the surfactant cetyltrimethyl ammonium bromide (CTAB). The crystalline phases of MMT and OMMT were characterized by microscopic performance analysis using an X-ray diffractometer (XRD) and scanning electron microscope (SEM). The effects of rubber, attapulgite, columnar diatomite, and disk diatomite on the technological and rheological properties of OMMT-modified asphalt were studied using a dynamic shear rheometer, and the low-temperature properties were determined from their creep characteristics by a bending beam rheometer. The short-term, long-term, and ultraviolet (UV) aging of modified asphalt were tested, respectively. After adding five types of modifiers to the asphalt, the high-temperature rheological and aging resistance of matrix asphalt and modified asphalt can be improved. In particular, it is shown that modification with OMMT with attapulgite as comodifier had a positive influence on asphalt thermo-oxidative aging and UV aging.
语种：
英文
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Bond behavior between multi-strand tendons and surrounding grout: Interface equivalent modeling method
作者：
Wang, Lei* ;Yuan, Ping;Zhang, Xuhui;Dong, You;Ma, Yafei;...
期刊：
Construction and Building Materials ,2019年226:61-71 ISSN：0950-0618
通讯作者：
Wang, Lei
作者机构：
[Ma, Yafei; Yuan, Ping; Wang, Lei; Zhang, Jianren] Changsha Univ Sci & Technol, Sch Civil Engn & Architecture, Changsha 410114, Hunan, Peoples R China.;[Zhang, Xuhui] Xiangtan Univ, Coll Civil Engn & Mech, Xiangtan 411105, Peoples R China.;[Dong, You] Hong Kong Polytech Univ, Dept Civil & Environm Engn, Hung Hom, Kowloon, Hong Kong, Peoples R China.
通讯机构：
[Wang, Lei] C;Changsha Univ Sci & Technol, Sch Civil Engn & Architecture, Changsha 410114, Hunan, Peoples R China.
关键词：
Interface equivalent modeling method;Bond stress-slip relationship;Multi-strand;Maximum bond stress;Bond behavior
摘要：
An interface equivalent modeling method is proposed in this study to describe the bond behavior between multi-strand tendons and surrounding grout. The interface equivalent principle is firstly proposed to determine the effective bond interface between tendons and grout considering the effects of the quantity, the arrangement and the space of strands. Then, the maximum bond stress of the multi-strand tendons provided by the interface is derived and incorporated into the existing bond stress-slip relationship to characterize the bond of multi-strand tendons. Subsequently, a pull-out numerical model incorporating the considered effects is developed to predict pullout forces-slip response for tendons. Finally, a direct pull-out test on three strands tendons is designed to verify the interface equivalent modeling method by comparing with the numerical and experimental results. The proposed method is also validated against previous experiment on seven strand tendons. Results indicate that the proposed interface equivalent modeling method can reasonably predict the bond behavior between multi-strand tendons and surrounding grout. The applicability and feasibility of the proposed equivalent modeling method is also investigated. (C) 2019 Elsevier Ltd. All rights reserved.
语种：
英文
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FRICTION AND WEAR OF MOO3/GRAPHENE OXIDE MODIFIED GLASS FIBER REINFORCED EPOXY NANOCOMPOSITES
作者：
He, Yuxin* ;Chen, Qiuyu;Liu, Hu* ;Zhang, Li;Wu, Dongyang;...
期刊：
MACROMOLECULAR MATERIALS AND ENGINEERING ,2019年304(8):1900166- ISSN：1438-7492
通讯作者：
He, Yuxin;Liu, Hu
作者机构：
[OuYang, Wei; He, Yuxin; Lu, Chang; Chen, Qiuyu; Wu, Dongyang] Henan Univ Sci & Technol, Coll Chem Engn & Pharmaceut, Luoyang 471023, Peoples R China.;[Liu, Hu; Liu, Chuntai] Zhengzhou Univ, Natl Engn Res Ctr Adv Polymer Proc Technol, Minist Educ, Key Lab Mat Proc & Mold, Zhengzhou 450002, Henan, Peoples R China.;[Zhang, Li] Luoyang Normal Univ, Coll Chem & Chem Engn, Luoyang 471023, Peoples R China.;[Jiang, Danfeng] Imperial Coll London, Royal Sch Mines, London SW7 2AZ, England.;[Zhang, Jiaoxia; Guo, Zhanhu] Univ Tennessee, Dept Chem & Biomol Engn, Integrated Composites Lab, Knoxville, TN 37996 USA.
通讯机构：
[He, Yuxin] H;[Liu, Hu] Z;Henan Univ Sci & Technol, Coll Chem Engn & Pharmaceut, Luoyang 471023, Peoples R China.;Zhengzhou Univ, Natl Engn Res Ctr Adv Polymer Proc Technol, Minist Educ, Key Lab Mat Proc & Mold, Zhengzhou 450002, Henan, Peoples R China.
关键词：
epoxy;friction/wear;glass fibers;graphene oxide;MoO3
摘要：
In order to further improve the tribological performance of glass fiber reinforced epoxy (GF/EP) composites, highly flexible, binder-free, molybdenum trioxide MoO3 nanobelt/graphene oxide (GO) film (f-MoO3-GO) is prepared by a hydrothermal method. Herein, f-MoO3-GO is adopted to modify GF/EP composites prepared through the vacuum-assisted resin transfer molding method. The neat GF/EP and MoO3-GO modified GF/EP composites are also fabricated for comparison. The tribological performance is performed using a ball-on-disc (“steel-on-polymer”) configuration under a dry sliding condition. The coefficient of friction is reduced from 0.61 for neat GF/EP composites down to 0.23 for f-MoO3-GO modified GF/EP (f-MoO3-GO/GF/EP) composites and the anti-wear performance is improved by more than four times. The worn surface morphological observation for the composite samples is used to explain the possible wear micro-mechanisms. The wear reducing effect of the f-MoO3-GO/GF/EP composites can be assigned to the increased self-lubricating effect of f-MoO3-GO. With the combined advantageous properties of the used individual components, these unique composites can be used for many other applications. © 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
语种：
英文
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Critical region method-based fatigue life prediction of notched steel wires of long-span bridges
作者：
Ma, Yafei;Wang, Guodong;Guo, Zhongzhao;Wang, Lei* ;Jiang, Tianyong;...
期刊：
Construction and Building Materials ,2019年225:601-610 ISSN：0950-0618
通讯作者：
Wang, Lei
作者机构：
[Ma, Yafei; Wang, Guodong; Wang, Lei; Jiang, Tianyong; Zhang, Jianren; Guo, Zhongzhao] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Hunan, Peoples R China.
通讯机构：
[Wang, Lei] C;Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Hunan, Peoples R China.
关键词：
Bridge engineering;Fatigue;Corrosion;Critical region method;Stress concentration;Finite element method
摘要：
Huge uncertainty exists in the corrosion process, and the dimensions of corrosion pits are quite random in practical engineering. Corrosion pit-induced stress concentration accelerates the initiation of fatigue cracks, ultimately reducing the fatigue life of bridge sling. This paper proposes a critical region method to predict the fatigue life of notched steel wires. This method considers the critical distance and the average stress amplitude of notched specimen. Fatigue loading tests on various notched steel wires are performed to simulate the effects of corrosion pit morphologies on the performance of steel wires. The relationships between notch dimensions and the fatigue lives of specimens are discussed. Following that, a fine-mesh three-dimensional solid model of notched steel wire is established by finite element method. The stress concentration coefficients and the stress distribution near the notch root are investigated, and the critical distance is also determined according to the local stress gradient of notched steel wire. The critical region-based fatigue life prediction method is validated using experimental fatigue life results of notched steel wires. A good agreement is observed between the theoretical predictions and experimental observations. © 2019 Elsevier Ltd
语种：
英文
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Investigations on mechanical properties and microtopography of electromagnetic self-piercing riveted joints with carbon fiber reinforced plastics/aluminum alloy 5052
作者：
Liang, Jusong;Jiang, Hao;Zhang, Jinsheng;Wu, Xianhe;Zhang, Xu;...
期刊：
Archives of Civil and Mechanical Engineering ,2019年19(1):240-250 ISSN：1644-9665
通讯作者：
Cui, Junjia
作者机构：
[Li, Guangyao; Cui, Junjia; Liang, Jusong; Jiang, Hao] Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.;[Zhang, Jinsheng; Wu, Xianhe] Chongqing Changan Automobile Co Ltd, Chongqing 401120, Peoples R China.;[Zhang, Xu] Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 410114, Hunan, Peoples R China.
通讯机构：
[Cui, Junjia] H;Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.
关键词：
Electromagnetic self-piecing riveting;Mechanical properties;Microtopography;Carbon fiber reinforced plastics
摘要：
In this paper, the mechanical properties of electromagnetic self-piercing riveted (E-SPR) joints with carbon fiber reinforced plastics (CFRP)/aluminum alloy (Al) 5052 were comprehensively investigated. Microtopography observations, hardness measurements and tensile-shear strength tests were performed by comparing with regular pressure self-piercing riveted (P-SPR) joints. Results showed that the undercut value of E-SPR joints was higher than that of P-SPR joints. The hardness values on rivet legs of E-SPR joints were larger and almost no difference on rivet heads between the E-SPR and P-SPR. In addition, it was found that mechanical properties of E-SPR joints were higher than that of P-SPR joints. The shear fracture appearance indicated that E-SPR joints with higher undercut were more difficult to rupture in the bottom of Al sheet.
语种：
英文
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Interfacial Engineering for High-Efficiency Nanorod Array-Structured Perovskite Solar Cells.
作者：
Cao, Bingbing;Liu, Haoran;Yang, Longkai;Li, Xin* ;Liu, Hu;...
期刊：
ACS Applied Materials & Interfaces ,2019年11(37):33770-33780 ISSN：1944-8244
通讯作者：
Li, Xin;Guo, Zhanhu;Mai, Xianmin;Gao, Qiang
作者机构：
[Li, Xin; Yang, Longkai; Liu, Haoran; Cao, Bingbing] Xiamen Univ, Pen Tung Sah Inst Micronano Sci & Technol, Xiamen 361005, Fujian, Peoples R China.;[Liu, Hu] Zhengzhou Univ, Minist Educ, Key Lab Mat Proc & Mold, Zhengzhou 450002, Henan, Peoples R China.;[Liu, Hu] Zhengzhou Univ, Natl Engn Res Ctr Adv Polymer Proc Technol, Zhengzhou 450002, Henan, Peoples R China.;[Zhang, Jiaoxia; Liu, Hu; Guo, Zhanhu] Univ Tennessee, Dept Chem & Biomol Engn, ICL, Knoxville, TN 37996 USA.;[Wang, Ning] Hainan Univ, State Key Lab Marine Resource Utilizat South Chin, Haikou 570228, Hainan, Peoples R China.
通讯机构：
[Li, Xin] X;[Guo, Zhanhu] U;[Mai, Xianmin] S;[Gao, Qiang] O;Xiamen Univ, Pen Tung Sah Inst Micronano Sci & Technol, Xiamen 361005, Fujian, Peoples R China.
关键词：
TiO2 nanorod;perovskite solar cells;atomic layer deposition;compact layer;depletion region
摘要：
TiO2 nanorod (NR) array for perovskite solar cells (PSCs) has attained great importance due to its superb power conversion efficiency (PCE) compared to that of the traditional mesoporous TiO2 film. A TiO2 compact layer for the growth of TiO2 NR array via spin-coating cannot meet the requirements for efficient NR-based PSCs. Herein, we have developed and demonstrated the insertion of a bifunctional extrathin TiO2 interlayer (5 nm) by atomic layer deposition (ALD) at the interface of the fluorine-doped tin oxide (FTO)/TiO2 compact layer to achieve alleviated electron exchange and a reduced energetic barrier. Thus, an accelerated extraction of electrons from TiO2 NR arrays via the compact layer and their transfer to the FTO substrate can improve the PSC efficiency. The thickness of the spin-coated TiO2 compact layer on the ALD-deposited TiO2 layer is spontaneously optimized. Finally, an outstanding efficiency of 20.28% has been achieved from a champion PSC with negligible hysteresis and high reliability. To the best of our knowledge, this is the first study demonstrating the superiority of TiO2-NR-based PSCs withstanding the dry heat and thermal cycling tests. The results are of great importance for the preparation of efficient and durable PSCs for real-world applications. Copyright © 2019 American Chemical Society.
语种：
英文
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A new Timoshenko beam model based on modified gradient elasticity: Shearing effect and size effect of micro-beam
作者：
Zhao, Bing* ;Chen, Jian;Liu, Tao* ;Song, Wenhao;Zhang, Jianren
期刊：
Composite Structures ,2019年223:110946 ISSN：0263-8223
通讯作者：
Zhao, Bing;Liu, Tao
作者机构：
[Song, Wenhao; Zhao, Bing; Liu, Tao; Chen, Jian] Changsha Univ Sci & Technol, Sch Civil Engn, Dept Mech, Changsha 410114, Hunan, Peoples R China.;[Zhang, Jianren] Changsha Univ Sci & Technol, Sch Civil Engn, Dept Bridge Engn, Changsha 410114, Hunan, Peoples R China.
通讯机构：
[Zhao, B; Liu, T] C;Changsha Univ Sci & Technol, Sch Civil Engn, Dept Mech, Changsha 410114, Hunan, Peoples R China.
关键词：
Modified gradient elasticity;Shearing effect;Size effect;Timoshenko micro-beam
摘要：
To investigate the shearing effect and size effect of micro-beams, a new Timoshenko beam model based on the modified gradient elasticity (MGE)is developed by using the variational principle. The new model can be simplified to the MGE Bernoulli-Euler beam model when the shearing effect is neglected, also can be simplified to the classical Timoshenko beam model when two internal length scales vanish. To solve this new model, a central finite difference method with virtual nodes is developed. Three numerical examples of the homogeneous beams and axially functionally graded (AFG)beams are considered in this paper. The size effect can be captured by the new model, i.e. the deflection, rotation angle and shearing angle decrease with the internal length scales increasing. The shearing effect, which plays an important role in deflection for a micro-beam, cannot be neglected even for the slender beam. © 2019
语种：
英文
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Thermomechanical investigation on the effect of nitroguanidine on the thermal expansion coefficient and glass transition temperature of double-base gun propellant
作者：
Qi, Le;Ma, Zhongliang;Liang, Jiahao;Xiao, Zhongliang* ;Dong, Mengyao;...
期刊：
Journal of Materials Research and Technology ,2019年8(5):4264-4272 ISSN：2238-7854
通讯作者：
Xiao, Zhongliang;Zhang, Jiaoxia;Liu, Chuntai;Fan, Jincheng;Ding, Tao
作者机构：
[Qi, Le; Ma, Zhongliang; Xiao, Zhongliang; Liang, Jiahao] North Univ China, Sch Environm & Safety Engn, Taiyuan 030051, Shanxi, Peoples R China.;[Xiao, Zhongliang] Nanjing Univ Sci & Technol, Sch Chem Engn, Nanjing 210094, Jiangsu, Peoples R China.;[Zhang, Jiaoxia; Dong, Mengyao; Guo, Zhanhu] Univ Tennessee, Dept Chem & Biomol Engn, ICL, Knoxville, TN 37996 USA.;[Liu, Chuntai; Dong, Mengyao] Zhengzhou Univ, Minist Educ, Key Lab Mat Proc & Mold, Zhengzhou 450002, Henan, Peoples R China.;[Liu, Chuntai; Dong, Mengyao] Zhengzhou Univ, Natl Engn Res Ctr Adv Polymer Proc Technol, Zhengzhou 450002, Henan, Peoples R China.
通讯机构：
[Xiao, Zhongliang] N;[Zhang, Jiaoxia] U;[Liu, Chuntai] Z;[Zhang, Jiaoxia] J;[Fan, Jincheng] C
关键词：
Flaky gun propellant;Coefficient of thermal expansion (CTE);Negative thermal expansion;Nitroguanidine (NQ);Glass transition temperature
摘要：
Thermal expansion coefficient (CTE) is a critical parameter of gun propellant because of its major role in fabrication, storage and combustion performance of the propellant. Further, controlling the CTE of the propellant is an effective solution to improve its loading density. Therefore, it is important to understand the thermal expansion of the propellant. To obtain the linear CTE of insensitive gun propellant, different weight percentages of NQ are added to the B# double-base absorbent propellant, the thermal mechanical analyzer (TMA) is employed to estimate their dimensional change over the temperature range of 213-323 K. The pure NQ flaky gun propellant exhibits a negative thermal expansion with a linear CTE of -2.006 x 10(-4) mm/mm K-1. The results show that the linear CTE of the B# double-base absorbent propellant is decreased by 53.74% as the concentration of NQ is increased to 30%, whereas the glass transition temperature increases with increasing the NQ content. (C) 2019 Published by Elsevier B.V.
语种：
英文
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Prediction of the performance and emissions of a spark ignition engine fueled with butanol-gasoline blends based on support vector regression
作者：
Zuo, Qingsong;Zhu, Xinning;Liu, Zhiqiang* ;Zhang, Jianping;Wu, Gang;...
期刊：
ENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY ,2019年38(3):- MAY-JUN ISSN：1944-7442
通讯作者：
Liu, Zhiqiang
作者机构：
[Zuo, Qingsong; Zhang, Jianping; Zhu, Xinning] Xiangtan Univ, Coll Mech Engn, Xiangtan 411100, Hunan, Peoples R China.;[Li, Yuelin; Wu, Gang; Liu, Zhiqiang] Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 411100, Hunan, Peoples R China.
通讯机构：
[Liu, Zhiqiang] C;Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 411100, Hunan, Peoples R China.
关键词：
butanol;alternative fuel;support vector regression;SI engine
摘要：
Butanol is considered as the more promising alternative fuel candidate because of its favorable chemical and physical properties over ethanol and methanol. In this study, the performance and emissions of a port fuel injected spark ignition engine fueled with butanol-gasoline blends (0–60 vol % butanol blended with gasoline referred as G100-B60), including brake thermal efficiency (BTE), brake specific fuel consumption (BSFC) and carbon monoxide (CO), unburned hydrocarbon (UHC), nitrogen oxide (NO x ), were investigated under various equivalence ratio. Among the butanol-gasoline blends, B30 performs well in engine performance and emissions due to its CO (2.3%–8.7%), UHC (12.4%–27.5%), and NO x (2.8%–19.6%) emissions compared to those of gasoline. Butanol can be a good alternative fuel to gasoline for its potential to reduce pollutant emissions. It is well known that engine tests are hard, time consuming, and high cost. Therefore, support vector regression (SVR) was used to predict the performance and emissions of the engine, where equivalence ratio and blend ratio were used as the input parameters, and BTE, BSFC, CO, UHC, and NO x were used as the output parameters. It was observed that the correlation coefficients and mean relative error were in the range of 0.9940–0.9998 and 0.1901–10.2570%, respectively. The SVR predictions of BTE, BSFC, CO, UHC, and NO x yielded the root-mean-squared-errors of 0.0511%, 4.6058 g/kW h, 0.9995% vol, 7.7503 ppm vol and 38.5861 ppm, respectively. It could be indicated that the SVR provided an accurate and simple approach to analyze performance and exhaust emissions of spark ignition engine. © 2018 American Institute of Chemical Engineers Environ Prog, 38:e13042, 2019. © 2018 American Institute of Chemical Engineers
语种：
英文
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Flexural Capacity Prediction of Corroded Prestressed Concrete Beams Incorporating Bond Degradation
作者：
Dai, Lizhao;Wang, Lei* ;Bian, Hanbing;Zhang, Jianren;Zhang, Xuhui;...
期刊：
Journal of Aerospace Engineering ,2019年32(4) ISSN：0893-1321
通讯作者：
Wang, Lei
作者机构：
[Ma, Yafei; Dai, Lizhao; Wang, Lei; Zhang, Jianren] Changsha Univ Sci & Technol, Sch Civil Engn, 960 Wanjiali Rd, Changsha 410114, Hunan, Peoples R China.;[Dai, Lizhao; Bian, Hanbing] Univ Lorraine, Lab Etude Microstruct & Mecan Mat, F-57045 Metz 01, France.;[Zhang, Xuhui] Xiangtan Univ, Coll Civil Engn & Mech, Xiangtan 411105, Hunan, Peoples R China.
通讯机构：
[Wang, Lei] C;Changsha Univ Sci & Technol, Sch Civil Engn, 960 Wanjiali Rd, Changsha 410114, Hunan, Peoples R China.
关键词：
Prestressed concrete beams;Flexural capacity;Strand corrosion;Bond degradation;Flexural cracks
摘要：
Strand corrosion can cause the flexural capacity deterioration of prestressed concrete (PC) beams. An analytical model incorporating the effects of strand cross-section reduction, material deterioration, concrete cracking, and bond degradation is proposed to predict the flexural capacity of corroded PC beams. The effect of flexural cracks is also included in the model. An equivalent bond stress concept is introduced to consider the effect of flexural cracks, which is further implemented into the flexural capacity prediction of corroded PC beams. The proposed model is validated by the experimental results collected from the previous studies. Results show that the proposed model can give an accurate prediction for the flexural capacity of corroded PC beams. Considering the effect of flexural cracks can improve the precision of the prediction model. The flexural capacity deterioration of PC beams depends on corrosion degree. Strand corrosion less than 5.5% can lead to a slight decrement of flexural capacity. As corrosion progresses the flexural capacity would exhibit a significant deterioration. (c) 2019 American Society of Civil Engineers.
语种：
英文
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Concrete cracks detection based on FCN with dilated convolution
作者：
Zhang, Jianming;Lu, Chaoquan;Wang, Jin* ;Wang, Lei;Yue, Xiao-Guang
期刊：
Applied Sciences-Basel ,2019年9(13) ISSN：2076-3417
通讯作者：
Wang, Jin
作者机构：
[Zhang, Jianming; Wang, Jin; Lu, Chaoquan] Changsha Univ Sci & Technol, Sch Comp & Commun Engn, Hunan Prov Key Lab Intelligent Proc Big Data Tran, Changsha 410114, Hunan, Peoples R China.;[Wang, Jin] Fujian Univ Technol, Sch Informat Sci & Engn, Fuzhou 350118, Fujian, Peoples R China.;[Wang, Lei] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Hunan, Peoples R China.;[Yue, Xiao-Guang] Rajamangala Univ Technol Rattanakosin, Rattanakosin Int Coll Creat Entrepreneurship, Nakhon Pathom 73170, Thailand.
通讯机构：
[Wang, Jin] C;[Wang, Jin] F;Changsha Univ Sci & Technol, Sch Comp & Commun Engn, Hunan Prov Key Lab Intelligent Proc Big Data Tran, Changsha 410114, Hunan, Peoples R China.;Fujian Univ Technol, Sch Informat Sci & Engn, Fuzhou 350118, Fujian, Peoples R China.
关键词：
Crack detection;Dilated convolution;FCN;Residual network;Semantic segmentation
摘要：
In civil engineering, the stability of concrete is of great significance to safety of people's life and property, so it is necessary to detect concrete damage effectively. In this paper, we treat crack detection on concrete surface as a semantic segmentation task that distinguishes background from crack at the pixel level. Inspired by Fully Convolutional Networks (FCN), we propose a full convolution network based on dilated convolution for concrete crack detection, which consists of an encoder and a decoder. Specifically, we first used the residual network to extract the feature maps of the input image, designed the dilated convolutions with different dilation rates to extract the feature maps of different receptive fields, and fused the extracted features from multiple branches. Then, we exploited the stacked deconvolution to do up-sampling operator in the fused feature maps. Finally, we used the SoftMax function to classify the feature maps at the pixel level. In order to verify the validity of the model, we introduced the commonly used evaluation indicators of semantic segmentation: Pixel Accuracy (PA), Mean Pixel Accuracy (MPA), Mean Intersection over Union (MIoU), and FrequencyWeighted Intersection over Union (FWIoU). The experimental results show that the proposed model converges faster and has better generalization performance on the test set by introducing dilated convolutions with different dilation rates and a multi-branch fusion strategy. Our model has a PA of 96.84%, MPA of 92.55%, MIoU of 86.05% and FWIoU of 94.22% on the test set, which is superior to other models. © 2019 by the authors.
语种：
英文
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Effect of Ta2O5 addition on thermophysical and mechanical properties of (Sm0.5Gd0.3Yb0.2)2Ce2O7 compounds
作者：
Zhao, Yongtao;Zhang, Junhui;Zhang, Hongsong* ;Fei, Wang* ;Chen, Xiaoge;...
期刊：
Ceramics International ,2019年45(17):21341-21347 ISSN：0272-8842
通讯作者：
Zhang, Hongsong;Fei, Wang
作者机构：
[Zhang, Hongsong; Zhao, Yongtao; Zhang, Junhui] Henan Univ Engn, Dept Mech Engn, Zhengzhou 451191, Henan, Peoples R China.;[Chen, Xiaoge] Henan Univ Engn, Dept Civil Engn, Zhengzhou 451191, Henan, Peoples R China.;[Fei, Wang] Henan Univ Engn, Dept Mat & Chem, Zhengzhou 451191, Henan, Peoples R China.;[Yang, Xianfeng] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410014, Hunan, Peoples R China.
通讯机构：
[Zhang, Hongsong; Fei, Wang] H;Henan Univ Engn, Dept Mech Engn, Zhengzhou 451191, Henan, Peoples R China.;Henan Univ Engn, Dept Mat & Chem, Zhengzhou 451191, Henan, Peoples R China.
关键词：
Mechanical properties;Ta2O5 addition;Thermal barrier coatings;Thermophysical properties
摘要：
In this study, the (Sm0.5Gd0.3Yb0.2)2(Ce1−xTax)2O7+x oxides were obtained by high-temperature solid-state sintering. The phase lattice, micro-structure, thermal-physical and mechanical performances of samples were examined. The synthesised compounds exhibit a single fluorite-type lattice, and they also have relatively dense microscopic structures. The differences in atomic weight and ionic radius between the solute and host kations enable a reduction of thermal conductivity of bulk samples. The reduced thermal expansion coefficient and the elevated elastic modulus are ascribed to the lower ion-radius of Ta5+ compared to Ce4+. The addition of “soft” Ta2O5 reduces the micro-hardness and increases the fracture toughness. The presented results herein provide an effective approach to ameliorate the fracture toughness of ceramics for thermal barrier coatings. © 2019 Elsevier Ltd and Techna Group S.r.l.
语种：
英文
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Molecular dynamics investigation of interfacial adhesion between oxidised bitumen and mineral surfaces
作者：
Gao, Yangming;Zhang, Yuqing* ;Yang, Yang;Zhang, Junhui;Gu, Fan
期刊：
Applied Surface Science ,2019年479:449-462 ISSN：0169-4332
通讯作者：
Zhang, Yuqing
作者机构：
[Zhang, Yuqing; Gao, Yangming; Gu, Fan] Aston Univ, Aston Inst Mat Res, Birmingham B4 7ET, W Midlands, England.;[Zhang, Yuqing; Gao, Yangming; Gu, Fan] Aston Univ, Engn Syst & Management Grp, Birmingham B4 7ET, W Midlands, England.;[Yang, Yang] Aston Univ, Bioenergy Res Grp, European Bioenergy Res Inst, Birmingham B4 7ET, W Midlands, England.;[Zhang, Junhui] Changsha Univ Sci & Technol, Natl Engn Lab Highway Maintenance Technol, Changsha, Hunan, Peoples R China.
通讯机构：
[Zhang, Yuqing] A;Aston Univ, Aston Inst Mat Res, Birmingham B4 7ET, W Midlands, England.;Aston Univ, Engn Syst & Management Grp, Birmingham B4 7ET, W Midlands, England.
关键词：
Bitumen aging;Interfacial adhesion;Mineral surfaces, molecular dynamics;Oxidised bitumen;Water damage
摘要：
The interfacial adhesion between oxidised bitumen and mineral surfaces at dry and wet conditions was investigated using molecular dynamics (MD) simulations. Molecular models were built for virgin and oxidised bitumen components including saturate, aromatic, resin and asphaltenes. The bitumen models and four representative mineral substrates (namely quartz, calcite, albite and microcline) were employed to construct bitumen-mineral interface systems. These models were validated by the experimental results and MD simulations reported in the literature. The hardening mechanism of the aged bitumen was analysed by comparing the density, cohesive energy density and fraction of free volume between the virgin and oxidised bitumen. Work of adhesion was computed to quantify the adhesive bonding property of the bitumen-mineral interface systems for the virgin, lightly oxidised and heavily oxidised bitumen models under dry and wet conditions. Results show that the oxidised products (carbonyl and sulfoxide) strengthen the intermolecular bonding, resulting in molecular aggregation and physical hardening of the aged bitumen. When bitumen becomes oxidised at the dry condition, the interfacial adhesion of bitumen-acidic minerals (quartz) is dominated by van der Waals interaction which decreases due to the increased bitumen-quartz intermolecular distance caused by the aggregated bitumen molecules during aging. In comparison, the interfacial adhesion of bitumen-strong alkali minerals (albite and microcline) is dominated by electrostatic energy which increases due to higher polarity introduced by the oxidised products. For the bitumen-weak alkali mineral (calcite), the interfacial adhesion is attributed to both electrostatic energy and van der Waals energy, where compared to the virgin bitumen, the electrostatic energy becomes lower for the lightly-oxidised bitumen due to the increased bitumen-mineral distance but becomes higher for the heavily-oxidised bitumen due to higher polarity. At wet condition, water is the dominating factor that affects (weakens) the interfacial adhesion between the bitumen and the acidic minerals (quartz), and the oxidative aging of bitumen is the major factor that affects (strengthens) the interfacial adhesion between the bitumen and the strongly alkaline minerals (albite and microcline). For the weak alkali minerals such as calcite, both water and bitumen aging can significantly affect the interfacial adhesion. © 2019 Elsevier B.V.
语种：
英文
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Graphene oxide based dopamine mussel-like cross-linked polyethylene imine nanocomposite coating with enhanced hexavalent uranium adsorption
作者：
Li, Songwei;Yang, Peipei;Liu, Xianhu* ;Zhang, Jiaoxia;Xie, Wei;...
期刊：
Journal of Materials Chemistry A ,2019年7(28):16902-16911 ISSN：2050-7488
通讯作者：
Liu, Xianhu
作者机构：
[Liu, Xianhu; Liu, Chuntai; Yang, Peipei; Li, Songwei] Zhengzhou Univ, Natl Engn Res Ctr Adv Polymer Proc Technol, Zhengzhou 450002, Henan, Peoples R China.;[Liu, Xianhu; Liu, Chuntai; Guo, Zhanhu] Zhengzhou Univ, Minist Educ, Key Lab Mat Proc & Mold, Zhengzhou 450002, Henan, Peoples R China.;[Zhang, Jiaoxia; Wang, Chao; Xie, Wei; Guo, Zhanhu] Univ Tennessee, Dept Chem & Biomol Engn, ICL, Knoxville, TN 37996 USA.;[Zhang, Jiaoxia] Jiangsu Univ Sci & Technol, Sch Mat Sci & Engn, Zhenjiang 212003, Jiangsu, Peoples R China.;[Xie, Wei] Changsha Univ Sci & Technol, Educ Dept, Key Lab Lightweight & Reliabil Technol Engn Vehic, Changsha, Hunan, Peoples R China.
通讯机构：
[Liu, Xianhu] Z;Zhengzhou Univ, Natl Engn Res Ctr Adv Polymer Proc Technol, Zhengzhou 450002, Henan, Peoples R China.;Zhengzhou Univ, Minist Educ, Key Lab Mat Proc & Mold, Zhengzhou 450002, Henan, Peoples R China.
摘要：
Polydopamine (pDA) self-polymerized from mussel-substance dopamine (DA) induced the grafting of polyethylene imine (PEI) between graphene oxide (GO) interlayers to form the GO-pDA-PEI adsorbent for capturing U(vi). The as-prepared GO-pDA-PEI has a hexavalent uranium (U(vi)) adsorption capacity of 530.6 mg g-1, which is 177% higher than that of pristine GO. Both thermodynamic and kinetic studies indicate a spontaneous and exothermic chemisorption process. The adsorbent demonstrates high adsorption capability and stability even after 5cycles of adsorption-desorption processes. The enhanced U(vi) adsorption capability was due to the unique characteristics of the nanoadsorbent, i.e., the ability to provide enough movement space and highly active sites for the adsorption of U(vi). © 2019 The Royal Society of Chemistry.
语种：
英文
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一种无机结合料圆柱形试件成型用试模
发明/设计人：
魏建国;侯剑楠;李平;张青江;郜晋生;...
申请/专利权人：
长沙理工大学;山西路桥建设集团有限公司
申请/专利号：
CN201820071866.5
申请时间：
2018-01-16
公开号：
CN207964399U
公开时间：
2018-10-12
摘要：
本实用新型公开了一种无机结合料圆柱形试件成型用试模,由试模上垫块、试模下垫块、插销杆、筒模与滑块组成,所述试模下垫块设置有两个插销孔,所述滑块两侧为圆弧状凸榫,与筒模的凹槽榫接构成整体,使用该实用新型成型无机结合料试件时,能够利用人工脱模代替脱模机工作,具有造价经济,操作简单等特点。
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Small Sample Face Recognition Algorithm Based on Novel Siamese Network
作者：
Jianming Zhang;Xiaokang Jin;Yukai Liu;Arun Kumar Sangaiah;Jin Wang 0001
期刊：
Journal of Information Processing Systems ,2018年14(6):1464-1479 ISSN：1976-913X
通讯作者：
Zhang, J.
作者机构：
[Arun Kumar Sangaiah] VIT;[Jianming Zhang; Xiaokang Jin; Yukai Liu; Jin Wang 0001] Hunan Provincial Key Laboratory of Intelligent Processing of Big Data on Transportation and School of Computer and Communication Engineering, Changsha University of Science and Technology
通讯机构：
Hunan Provincial Key Laboratory of Intelligent Processing of Big Data on Transportation, School of Computer and Communication Engineering, Changsha University of Science and Technology, Changsha, China
关键词：
Convolutional Neural Network;Face Recognition;Loss Function;Siamese Network;Small Sample
摘要：
In face recognition, sometimes the number of available training samples for single category is insufficient. Therefore, the performances of models trained by convolutional neural network are not ideal. The small sample face recognition algorithm based on novel Siamese network is proposed in this paper, which doesn't need rich samples for training. The algorithm designs and realizes a new Siamese network model, SiameseFace1, which uses pairs of face images as inputs and maps them to target space so that the L2 norm distance in target space can represent the semantic distance in input space. The mapping is represented by the neural network in supervised learning. Moreover, a more lightweight Siamese network model, SiameseFace2, is designed to reduce the network parameters without losing accuracy. We also present a new method to generate training data and expand the number of training samples for single category in AR and labeled faces in the wild (LFW) datasets, which improves the recognition accuracy of the models. Four loss functions are adopted to carry out experiments on AR and LFW datasets. The results show that the contrastive loss function combined with new Siamese network model in this paper can effectively improve the accuracy of face recognition. © 2018 KIPS.
语种：
英文
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高液限粘土路基加宽的有限元分析
作者：
刘涛;张军;黄博
期刊：
公路工程 ,2018年43(5):220-225,265 ISSN：1674-0610
作者机构：
[刘涛] 常德市交通建设监理咨询有限公司;[张军] 湖南省莲株高速公路建设开发有限公司;[黄博] 长沙理工大学
关键词：
有限元分析;路基加宽;高液限黏土;不均匀沉降;处治方法
摘要：
利用ABAQUS软件建立高液限黏土路基加宽有限元模型，对不同的差异沉降处治方法进行了仿真模拟，分析了从竣工时至工后若干年时路基的应力状态、竖向位移和水平位移的变化情况，结合应力位移云图及沉降位移曲线，获得了改扩建路基的应力应变分布规律和差异沉降变化规律。研究表明，路基拓宽1 a后沉降便已基本稳定，开挖台阶及加设土工格栅可以有效地减小施工时的差异沉降，并在一定程度上减小工后沉降。
语种：
中文
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Oxidation Removal of Nitric Oxide from Flue Gas Using an Ultraviolet Light and Heat Coactivated Oxone System
作者：
Liu, Yangxian* ;Wang, Yan;Yin, Yanshan;Pan, Jianfeng;Zhang, Jun
期刊：
Energy & Fuels ,2018年32(2):1999-2008 ISSN：0887-0624
通讯作者：
Liu, Yangxian
作者机构：
[Liu, Yangxian; Pan, Jianfeng; Wang, Yan] Jiangsu Univ, Sch Energy & Power Engn, Zhenjiang 212013, Jiangsu, Peoples R China.;[Yin, Yanshan] Changsha Univ Sci & Technol, Key Lab Efficient & Clean Energy Utilizat Educ, Dept Hunan Prov, Changsha 410000, Hunan, Peoples R China.;[Zhang, Jun] Southeast Univ, Minist Educ, Key Lab Energy Thermal Convers & Control, Nanjing 210096, Jiangsu, Peoples R China.
通讯机构：
[Liu, Yangxian] J;Jiangsu Univ, Sch Energy & Power Engn, Zhenjiang 212013, Jiangsu, Peoples R China.
摘要：
The oxidation removal process of nitric oxide (NO) from flue gas using an ultraviolet (UV) light and heat coactivated ozone (potassium peroxymonosulfate, 2KHSO(5)center dot KHSO4 center dot K2SO4) system in an UV (254 nm)-impinging stream reactor was studied. The main process parameters (e.g., light intensity, oxone concentration, solution temperature, solution pH, flue gas composition, and flow rate of flue gas and solution), products, mechanism, and kinetics of NO removal were studied. The results show that UV and ozone have a significant synergistic effect for promoting free radical production and improving NO removal. NO removal was improved via increasing the light intensity, ozone concentration, or solution flow rate and was inhibited with increasing the NO concentration, SO2 concentration, or flue gas flow rate. Solution temperature and pH have double impacts on NO removal. UV light activation for oxone is the main source of SO4-center dot and (OH)-O-center dot. Heat activation for oxone is the complementary source of SO4-center dot and (OH)-O-center dot. SO4-center dot and (OH)-O-center dot are the key oxidizing agents and play an important role in NO removal. Oxone plays a complementary role in NO removal. The NO removal process is a fast reaction and meets a total 1.44 order reaction (i.e., 1.0 order for NO and 0.44 order for oxone). The key kinetic parameters of NO removal were also determined.
语种：
英文
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Multiscale simulation of wind field on a long-span bridge site in mountainous area
作者：
Han, Yan;Shen, Lian* ;Xu, Guoji;Cai, C. S.* ;Hu, Peng;...
期刊：
Journal of Wind Engineering and Industrial Aerodynamics ,2018年177:260-274 ISSN：0167-6105
通讯作者：
Shen, Lian;Cai, C. S.
作者机构：
[Shen, Lian; Hu, Peng; Zhang, Jianren; Han, Yan] Changsha Univ Sci & Technol, Sch Civil Engn & Architecture, Changsha 410004, Hunan, Peoples R China.;[Shen, Lian] Changsha Univ, Sch Civil Engn, Changsha 410022, Hunan, Peoples R China.;[Shen, Lian; Xu, Guoji; Cai, C. S.] Louisiana State Univ, Dept Civil & Environm Engn, Baton Rouge, LA 70803 USA.
通讯机构：
[Shen, Lian] C;[Cai, C. S.] L;Changsha Univ, Sch Civil Engn, Changsha 410022, Hunan, Peoples R China.;Louisiana State Univ, Dept Civil & Environm Engn, Baton Rouge, LA 70803 USA.
关键词：
Inflow turbulence;Large eddy simulation;Weather Research and Forecast;Wind field in mountainous areas
摘要：
A multiscale coupling strategy is proposed in the present study to numerically simulate the wind field at bridge sites in mountainous areas. This paper mainly focuses on resolving the difficulty of configuring reasonable inlet boundary conditions to achieve the required wind field. Firstly, the inlet boundary values of the mean wind velocity in the mountainous area were provided by the Weather Research and Forecasting (WRF) mesoscale model. Then, the local wind environmental flows over the mountainous area were computed by the large eddy simulation (LES) in such a way that the Block Polynomial Interpolation (BPI) method was employed to interpolate the data from WRF to the grids at the inlet boundary of the LES computation domain. This BPI method provided a better solution to the inlet boundary problems caused by the “artificial cliff”. The inflow turbulence generating method was used for the input of the fluctuating wind speed at the inlet boundary, where the fluctuating wind field that satisfies the characteristics of the wind field in the mountainous area was simulated according to the data measured at the bridge site station by using the Weighted Amplitude Wave Superposition (WAWS) method. Finally, the proposed methodology was applied to the Lishui Bridge in China as a case study. The numerical predictions were found in good agreement with the monitored data, assuring the good capabilities of the proposed methodology and its potential uses in practical engineering. Meanwhile, the wind field from different wind directions was systematically studied and the characteristics for the detailed wind field distribution were analyzed. The presented methodology can be served as a reference to the refined simulation for the fluctuating wind field in mountainous areas.<br/> ©2018 Elsevier Ltd
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英文
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