Self-grown NiCuOx hybrids on a porous NiCuC substrate as an HER cathode in alkaline solution
作者：
Yu, Linping;Dang, Yanliu;Zeng, Julan;He, Junkai;Murphy, Steven C.;...
期刊：
Applied Surface Science ,2020年515:146117 ISSN：0169-4332
通讯作者：
Suib, Steven L.;Zhang, Jian;Dou, Yuhai
作者机构：
[Yu, Linping; Zeng, Julan] Changsha Univ Sci & Technol, Hunan Prov Key Lab Mat Protect Elect Power & Tran, Changsha 410114, Peoples R China.;[Kerns, Peter; Yu, Linping; He, Junkai; Murphy, Steven C.; Dang, Yanliu; Suib, Steven L.] Univ Connecticut, Dept Chem, U-3060,55 North Eagleville Rd, Storrs, CT 06269 USA.;[Zhang, Jian] Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 410114, Peoples R China.;[Dou, Yuhai] Griffith Univ, Ctr Clean Environm & Energy, Gold Coast 4222, Australia.
通讯机构：
[Suib, Steven L.] U;[Zhang, Jian] C;[Dou, Yuhai] G;Univ Connecticut, Dept Chem, U-3060,55 North Eagleville Rd, Storrs, CT 06269 USA.;Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 410114, Peoples R China.
关键词：
Electrocatalyst;Hydrogen evolution reaction;NiCuC substrate;NiCuOx hybrids
摘要：
Electrocatalysts converted directly from the substrates hold the key to achieve high catalytic activity and durability due to their high bonding strength, intimate electronic contact, and tunable phase composition. Herein, an electrically conductive porous NiCuC substrate was adopted to develop a multi-porous NiCuOx/NiCuC hydrogen evolution reaction (HER) catalyst using a one-step oxidation method in this research. The NiCuOx hybrids were characterized as three typical layers: an outer layer with NiCuO2 solid solution phase, a partially oxidized intermediate layer, and an inner layer with limited stable oxygen content. The NiCuOx/NiCuC possesses abundant Ni(Ⅱ)-Cu(Ⅱ) sites to accelerate the Volmer step via the electrostatic effect with OH–, numerous metallic NiCu sites to facilitate the H adsorption, and highly accessible channels to promote the Heyrovsky step during HER catalysis. As a result, high electrocatalytic performance was obtained with an overpotential of 116 mV at a current density of 10 mA cm−2 in 1.0 M potassium hydroxide, and a stable catalytic performance during the HER process for more than 24 h. © 2020 Elsevier B.V.
语种：
英文
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冷冻干燥法制备有机蒙脱土及其改性沥青性能研究
作者：
张帅;张健
期刊：
材料导报 ,2020年34(2):04037-04042 ISSN：1005-023X
通讯作者：
Zhang, Jian(JZhang4343@126.com)
作者机构：
[张帅; 张健] School of Automotive and Mechanical Engineering, Changsha University of Science and Technology, Changsha;410114, China;[张帅; 张健] 410114, China
通讯机构：
School of Automotive and Mechanical Engineering, Changsha University of Science and Technology, Changsha, China
关键词：
沥青;有机蒙脱土;冷冻干燥;流变性能;老化性能
摘要：
采用冷冻干燥法制备了有机化蒙脱土(OMMT),利用X射线衍射(XRD)仪和扫描电子显微镜(SEM)研究了冷冻干燥对OMMT层间距和表面形态的影响;使用OMMT制备了改性沥青,研究了它对改性沥青物理和高低温流变性能以及抗老化性能的影响。结果表明,冷冻干燥能够进一步扩大OMMT的层间距并细化OMMT颗粒的尺寸;OMMT的引入增加了改性沥青的软化点和车辙因子,显著提高了改性沥青的高温性能。对OMMT改性沥青进行薄膜烘箱老化(TFOT)和压力容器老化(PAV),分别模拟沥青的短期(ST)和长期(LT)老化。与原始沥青相比,OMMT改性沥青TFOT后的车辙因子和软化点变化较小,PAV后的蠕变刚度和疲劳因子较低,改性沥青的老化指数明显低于原始沥青。OMMT的引入增强了改性沥青的高温性能并有效抑制了改性沥青的热氧老化,当OMMT含量为3%(质量分数)时改性沥青具有最佳的性能。
语种：
中文
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Experimental study on thermal expansion coefficient of composite multi-layered flaky gun propellants
作者：
Liang, Taixin* ;Qi, Le;Ma, Zhongliang;Xiao, Zhongliang;Wang, Yang;...
期刊：
Composites Part B: Engineering ,2019年166:428-435 ISSN：1359-8368
通讯作者：
Liang, Taixin;Lu, Na;Liu, Chuntai;Xie, Wei;Ding, Tao
作者机构：
[Qi, Le; Ma, Zhongliang; Liang, Taixin] 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.;[Wang, Yang; Lu, Na] Purdue Univ, Lyles Sch Civil Engn, Sch Mat Engn, Birck Nanotechnol Ctr, W Lafayette, IN 47906 USA.;[Zhang, Jiaoxia; Liu, Hu; Guo, Zhanhu] Univ Tennessee, ICL, Dept Chem & Biomol Engn, Knoxville, TN 37996 USA.;[Liu, Hu; Liu, Chuntai] Zhengzhou Univ, Key Lab Mat Proc & Mold, Minist Educ, Zhengzhou 450002, Henan, Peoples R China.
通讯机构：
[Liang, Taixin] N;[Lu, Na] P;[Liu, Chuntai] Z;[Xie, Wei] C;[Ding, Tao] H
关键词：
Flaky gun propellant;Thermal expansion coefficient;TMA (thermal mechanical analyzer) test;Variable burning-rate gun propellant
摘要：
Improving the burning progressivity is an effective approach to improve the muzzle velocities of projectile of a gun. Composite multi-layered flaky gun propellant is a combination of a fast-burning inner layer and a slow-burning outer layer. It has an obvious burning progressivity which decreases the pressure in bore and increases the muzzle velocity, thus this characteristic is widely concerned by the research of gun propellant. The thermal expansion coefficient of composite multi-layered gun propellant has a significant influence on the combustion performance. Therefore, understanding the thermal expansion properties of the composite multi-layered gun propellant is important. In this study, the thermal expansion coefficients were measured by thermal mechanical analyzer (TMA) for a three-layered flaky gun propellant, and the influence of laminating and coating flaky gun propellant on thermal expansion coefficient was investigated. The results showed that the slow-burning layers had a higher thermal expansion coefficient than the faster-burning layers, the thermal expansion coefficient of slow-burning layers was 4–5 times bigger than that of fast-burning layers, and the order of magnitudes was 1 × 10 −5 K −1 . The laminating and coating had a great influence on the thermal expansion coefficient of flaky gun propellant, the thermal expansion coefficient of laminate sample was 10 times greater than that of the original sample, and the order of magnitudes for two layers and three layers propellant reached 1 × 10 −4 K −1 . Furthermore, the theoretical relations between the thermal expansion coefficient of axial and the thermal expansion coefficient of the fast and slow burning layer were derived. © 2019 Elsevier Ltd
语种：
英文
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In Situ Growth of Ni2P-Cu3P Bimetallic Phosphide with Bicontinuous Structure on Self-Supported NiCuC Substrate as an Efficient Hydrogen Evolution Reaction Electrocatalyst
作者：
Yu, Linping;Zhang, Jian;Dang, Yanliu;He, Junkai;Tobin, Zachary;...
期刊：
ACS CATALYSIS ,2019年9(8):6919-6928 ISSN：2155-5435
通讯作者：
Suib, Steven L.;Dou, Yuhai;He, Yuehui
作者机构：
[Yu, Linping] Changsha Univ Sci & Technol, Sch Chem & Food Engn, Changsha 410114, Hunan, Peoples R China.;[Kerns, Peter; Yu, Linping; Tobin, Zachary; He, Junkai; Dang, Yanliu; Suib, Steven L.] Univ Connecticut, Dept Chem, U-3060,SS North Eagleville Rd, Storrs, CT 06269 USA.;[Zhang, Jian] Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 410114, Hunan, Peoples R China.;[Dou, Yuhai] Griffith Univ, Ctr Clean Environm & Energy, Gold Coast 4222, Australia.;[Jiang, Yao; He, Yuehui] Cent S Univ, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China.
通讯机构：
[Suib, Steven L.] U;[Dou, Yuhai] G;[He, Yuehui] C;Univ Connecticut, Dept Chem, U-3060,SS North Eagleville Rd, Storrs, CT 06269 USA.;Griffith Univ, Ctr Clean Environm & Energy, Gold Coast 4222, Australia.
关键词：
bicontinuous structure;bimetallic phosphide;catalyst;hydrogen evolution reaction;Ni2P-Cu3P
摘要：
A direct and effective approach is proposed to fabricate bimetallic phosphide Ni2P-Cu3P with controllable phase composition and distribution for catalytic hydrogen evolution reaction (HER). Unlike previously reported precursors, a porous Ni-Cu alloy incorporated with graphitic carbon (NiCuC) prepared via powder metallurgy is employed herein, and the generated Ni2P-Cu3P@NiCuC possesses a hierarchical porous structure and controllable phase composition due to the high porosity and tunable Ni/Cu ratio of the precursor. With an optimal Cu content of 30.0 wt %, the catalyst demonstrates the highest catalytic activity due to a synergistic interaction between different metallic phosphide sites and the facilitated mass transport. Meanwhile, density functional theory (DFT) calculation reveals that the atomic interaction of Ni2P-Cu3P substantially lower the activation barrier for enhanced HER catalytic activity. The powder metallurgy provides an approach for the design of bimetallic phosphide electrocatalysts for HER and other catalytic applications. Copyright © 2019 American Chemical Society.
语种：
英文
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Graphene-tailored molecular bonds for advanced hydrogen and lithium storage performance
作者：
Huang, Yuqin;Xia, Guanglin* ;Zhang, Jian;Guo, Zaiping;Yu, Xuebin*
期刊：
Energy Storage Materials ,2019年17:178-185 ISSN：2405-8297
通讯作者：
Xia, Guanglin;Yu, Xuebin
作者机构：
[Huang, Yuqin; Yu, Xuebin] Fudan Univ, Dept Mat Sci, Shanghai 200433, Peoples R China.;[Guo, Zaiping; Huang, Yuqin; Xia, Guanglin] Univ Wollongong, Inst Superconducting & Elect Mat, North Wollongong, NSW 2522, Australia.;[Zhang, Jian] Changsha Univ Sci & Technol, Hunan Prov Key Lab Safety Design & Reliabil Techn, Changsha 410114, Hunan, Peoples R China.;[Yu, Xuebin] Shanghai Innovat Inst Mat, Shanghai 200444, Peoples R China.
通讯机构：
[Xia, Guanglin] U;[Yu, Xuebin] S;Univ Wollongong, Inst Superconducting & Elect Mat, North Wollongong, NSW 2522, Australia.;Shanghai Innovat Inst Mat, Shanghai 200444, Peoples R China.
关键词：
Alanates;Complex hydrides;Graphene;Hydrogen storage;Thermodynamics
摘要：
The practical application of sodium alanate (NaAlH4) as a hydrogen and lithium storage material has attracted intensive attention. The high energy barrier for breaking the Al-H bonds of NaAlH4, however, remains a key challenge. Here, we report that graphene could act as an effective platform to tailor the metal-hydrogen bonds of NaAlH4 through their favorable molecular interaction. Theoretical and experimental results confirm that graphene is capable of weakening the Al-H bonds of NaAlH4, thus facilitating the breaking and recombination of Al-H bonds towards advanced hydrogen and lithium storage performance. In addition, owing to this favorable interaction, a robust nanostructure composed of homogeneous NaAlH4 nanoparticles with an average size of ~12 nm encapsulated in graphene nanosheets has been developed via a facile solvent evaporation induced deposition method with a tunable loading and distribution. The synergistic effects of the favorable molecular interaction between graphene and NaAlH4 and the noticeable decrease in particle size significantly boost the hydrogen and lithium storage performances of NaAlH4. This method provides new avenues to tailoring the molecular bonds of metal hydrides for a new range of applications in various fields. © 2018
语种：
英文
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Investigation of bogie positions on the aerodynamic drag and near wake structure of a high-speed train
作者：
Gao, Guangjun;Li, Feng;He, Kan;Wang, Jiabin;Zhang, Jie* ;...
期刊：
Journal of Wind Engineering and Industrial Aerodynamics ,2019年185:41-53 ISSN：0167-6105
通讯作者：
Zhang, Jie
作者机构：
[He, Kan; Li, Feng; Wang, Jiabin; Zhang, Jie; Gao, Guangjun] Cent S Univ, Key Lab Traff Safety Track, Minist Educ, Changsha 410075, Hunan, Peoples R China.;[He, Kan; Li, Feng; Wang, Jiabin; Zhang, Jie; Gao, Guangjun] Joint Int Res Lab Key Technol Rail Traff Safety, Changsha 410075, Hunan, Peoples R China.;[He, Kan; Li, Feng; Wang, Jiabin; Zhang, Jie; Gao, Guangjun] Natl & Local Joint Engn Res Ctr Safety Technol Ra, Changsha 410075, Hunan, Peoples R China.;[Miao, Xiujuan] Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 410076, Hunan, Peoples R China.;[Miao, Xiujuan] Key Lab Safety Design & Reliabil Technol Engn Veh, Changsha 410076, Hunan, Peoples R China.
通讯机构：
[Zhang, Jie] C;Cent S Univ, Key Lab Traff Safety Track, Minist Educ, Changsha 410075, Hunan, Peoples R China.
关键词：
Aerodynamics;Bogies (railroad rolling stock);Drag reduction;Navier Stokes equations;Railroad cars;Railroad transportation;Railroads;Rhenium compounds;Speed;Turbulence models;Vehicle performance;Wakes;Wind tunnels;Aero-dynamic performance;Aerodynamic drag force;Bogie position;High speed train (HST);Near-wake structure;RANS;Two-equation turbulence models;Wind tunnel tests;Aerodynamic drag
摘要：
As train speed increases, the aerodynamic drag reduction becomes increasingly significant. The aim of this paper is to find out appropriate bogie positions to reduce the drag of a high-speed train. In this paper, based on the three-dimensional steady incompressible Reynolds-averaged N-S equations and the Realizable k-ε two-equation turbulence model, the effects of bogie positions on the aerodynamic performance and near wake of the three-carriage high-speed train are presented. The mesh resolution and methodology are validated against wind tunnel test. The results show that the front bogie position of the head car has a significant impact on the aerodynamic performance of the head car, leading to different aerodynamic drag forces. When the bogie moves towards the rear by 1 m and 2 m, the aerodynamic drag forces of the head car reduce by 7.75% and 10.56%, and the total drag decreases by 5.57% and 6.58%, respectively. © 2018 Elsevier Ltd
语种：
英文
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Multiple Anionic Transition-Metal Oxycarbide for Better Lithium Storage and Facilitated Multielectron Reactions
作者：
Cuan, Jing;Zhou, You;Zhang, Jian;Zhou, Tengfei;Liang, Gemeng;...
期刊：
ACS Nano ,2019年13(10):11665-11675 ISSN：1936-0851
通讯作者：
Guo, Zaiping;Yu, Xuebin
作者机构：
[Cuan, Jing; Guo, Zaiping; Liang, Gemeng; Zhou, Tengfei; Pang, Wei Kong] Univ Wollongong, Inst Superconducting & Elect Mat, Wollongong, NSW 2511, Australia.;[Guo, Zaiping] Univ Wollongong, Sch Mech Mat & Mechatron Engn, Wollongong, NSW 2511, Australia.;[Yu, Xuebin] Fudan Univ, Dept Mat Sci, Shanghai 200433, Peoples R China.;[Zhou, You] Ningbo Univ, Fac Mat Sci & Chem Engn, Ningbo 315211, Zhejiang, Peoples R China.;[Zhang, Jian] Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha 410015, Hunan, Peoples R China.
通讯机构：
[Guo, Zaiping] U;[Yu, Xuebin] F;Univ Wollongong, Inst Superconducting & Elect Mat, Wollongong, NSW 2511, Australia.;Univ Wollongong, Sch Mech Mat & Mechatron Engn, Wollongong, NSW 2511, Australia.;Fudan Univ, Dept Mat Sci, Shanghai 200433, Peoples R China.
关键词：
oxycarbide configurations;anion-centered chemistry;multielectron reactions;interface integrations;lithium ion batteries
摘要：
As an important class of multielectron reaction materials, the applications of transition-metal oxides (TMOs) are impeded by volume expansion and poor electrochemical activity. To address these intrinsic limitations, the renewal of TMOs inspires research on incorporating an advanced interface layer with multiple anionic characteristics, which may add functionality to support properties inaccessible to a single-anion TMO electrode. Herein, a transition-metal oxycarbide (TMOC, M = Mo) with more than one anionic species was prepared as an interface layer on a corresponding oxide. A multiple anionic TMOC possesses advantages of structural stability, abundant active sites, and elevated metal cation valence states. Such merits mitigate volume changes and enhance multielectron reactions significantly. The TMOC nanocomposite has a well-maintained capacity after 1000 cycles at 2 A·g-1 and fully resumed rate performance. In situ synchrotron X-ray powder diffraction (SXRPD) analysis unveils negligible volume expansions occurring upon oxycarbide layer coupling, with lattice spacing variation less than 1% during cycling. The lithium storage mechanism is further inspected by combined analysis of kinetics, SXRPD, and first-principles calculations. Superior to TMO, multielectron reactions of the TMOC electrode have been boosted due to easier rupture of the metal-oxygen bond. Such improvements underscore the importance of incorporating an oxycarbide configuration as a strategy to expand applications of TMOs. Copyright © 2019 American Chemical Society.
语种：
英文
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Microstructures and Mechanical Properties of Regular and Titanium Powder Filled Fibre Laser Lap Welded Dual-phase (DP) Steel
作者：
Yin, L-R* ;Wu, B-Y;Qu, H.;Zhang, J.
期刊：
Lasers in Engineering ,2019年44(4-6):341-353 ISSN：0898-1507
通讯作者：
Yin, L-R
作者机构：
[Qu, H.; Yin, L-R; Wu, B-Y] Changsha Univ Sci & Technol, Sch Automot & Mech Engn, Changsha 410114, Hunan, Peoples R China.;[Zhang, J.] Changsha Univ Sci & Technol, Hunan Prov Key Lab Intelligent Mfg Technol High P, Changsha 410114, Hunan, Peoples R China.
通讯机构：
[Yin, L-R] C;Changsha Univ Sci & Technol, Sch Automot & Mech Engn, Changsha 410114, Hunan, Peoples R China.
关键词：
Dual phase steel;Ductile fracture;Fiber lasers;Hardness;Martensite;Mechanical properties;Microstructure;Morphology;Shear strength;Soldered joints;Steel fibers;Welded steel structures;Welds;Yield stress;DP590;Laser lap welding;Microstructures and mechanical properties;Tempered martensite;Titanium powders;Welding joints;Welding parameters;Welding specimens;Welding
摘要：
To study the microstructures and mechanical properties of the welded joints of a dual-phase (DP) steel after laser lap welding, we performed the laser lap welding and laser powder filling with titanium powder lap welding of DP590 steel using a fiber laser with optimized welding parameters. The experimental results show that the microstructures of weld seam region of DP590 steel are mainly composed of martensite. There exists a softening zone in the weld joints, which is mainly originated from the generation of tempered martensite due to the thermal effect during laser welding. The hardness and yield strength of weld seam region for the welding specimens filled with titanium powder are both decreased, while the shear strength is increased relative to the unfilled ones. Analysis of shear fracture morphology shows that the welded joints of powder filled specimen exhibit obvious ductile fracture, and they have the better toughness and ductility as compared with the unfilled ones. ©2019 Old City Publishing, Inc.
语种：
英文
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Ultrathin high-performance electromagnetic wave absorbers with facilely fabricated hierarchical porous Co/C crabapples
作者：
Wu, Nannan;Liu, Chang;Xu, Dongmei;Liu, Jiurong* ;Liu, Wei;...
期刊：
Journal of Materials Chemistry C ,2019年7(6):1659-1669 ISSN：2050-7526
通讯作者：
Liu, Jiurong
作者机构：
[Liu, Jiurong; Wu, Nannan; Liu, Chang] Shandong Univ, Key Lab Liquid Solid Struct Evolut & Proc Mat, Minist Educ, Jinan 250061, Shandong, Peoples R China.;[Liu, Jiurong; Wu, Nannan; Liu, Chang] Shandong Univ, Sch Mat Sci & Engn, Jinan 250061, Shandong, Peoples R China.;[Zhang, Jiaoxia; Liu, Hu; Wu, Nannan; Guo, Zhanhu] Univ Tennessee, ICL, Dept Chem & Biomol Engn, Knoxville, TN 37996 USA.;[Liu, Wei; Xu, Dongmei] Shandong Univ, State Key Lab Crystal Mat, Jinan 250100, Shandong, Peoples R China.;[Liu, Hu] Zhengzhou Univ, Key Lab Mat Proc & Mold, Minist Educ, Natl Engn Res Ctr Adv Polymer Proc Technol, Zhengzhou 450002, Henan, Peoples R China.
通讯机构：
[Liu, Jiurong] S;Shandong Univ, Key Lab Liquid Solid Struct Evolut & Proc Mat, Minist Educ, Jinan 250061, Shandong, Peoples R China.;Shandong Univ, Sch Mat Sci & Engn, Jinan 250061, Shandong, Peoples R China.
关键词：
Bandwidth;Carbon;Circular waveguides;Cobalt;Electromagnetic waves;Absorber thickness;Absorption material;Electromagnetic wave absorber;Hierarchical porous;Multi scatterings;Solvothermal reactions;Strong absorptions;Structural feature;Electromagnetic wave absorption
摘要：
Extremely strong electromagnetic wave (EMW) absorption with a minimum reflection loss (RL) of −56.9 dB at 9.3 GHz at an absorber thickness of only 1.92 mm was observed for the hierarchical porous cobalt (Co)/carbon (C) crabapples, lab-made via a facile solvothermal reaction coupled with a following carbon reduction treatment. At an ultrathin thickness of 1.4 mm, the hierarchical porous Co/C crabapples (50 wt% filling content) provided 90% EMW absorption over a broad bandwidth of 5.9 GHz. A broad bandwidth of 5.8 GHz at 2.0 mm thickness was still achieved at a low filling ratio of 30 wt% filler content. This broad-band EMW absorption resulted from the synergy of cobalt and carbon with a significantly improved impedance matching level. The strong magnetism of cobalt endowed the composites with strong absorption ability and thin absorber thickness. The unique porous structural features also contributed to the enhanced EMW absorption by inducing multi-scatterings. The hierarchical porous Co/C crabapples with high absorbing performance together with ultrathin absorber thickness can be applied as a promising EMW absorption material. © The Royal Society of Chemistry.
语种：
英文
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以学生能力培养为目标的混合式教学的研究
作者：
寇莉莉;华熳煜;戴晓元;张健
期刊：
科技创新导报 ,2019年16(05):217-219 ISSN：1674-098X
作者机构：
长沙理工大学汽车与机械工程学院 湖南长沙 410114;[华熳煜; 戴晓元; 张健; 寇莉莉] 长沙理工大学
关键词：
能力培养;混合式教学;自主学习;协作学习
摘要：
本文以《冲压工艺与模具设计》课程的教学改革研究为切入点,根据课程特点,结合慕课、分组教学和实践教学等方法,建立了混合式多元教学模型,探讨了混合式教学对于学生能力培养的优势。采用混合式教学模式可以激发学生的学习兴趣,培养学生自主学习、协作学习和分析探究解决问题等能力,教学效果得到了同学们的支持和肯定。
语种：
中文
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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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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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有机化蒙脱土的制备及对沥青改性的研究
作者：
张帅;华熳煜;张健
期刊：
公路与汽运 ,2019年(2):88-92 ISSN：1671-2668
作者机构：
长沙理工大学 汽车与机械工程学院,湖南 长沙,410114;[华熳煜; 张帅; 张健] 长沙理工大学
关键词：
公路;有机化蒙脱土;沥青改性;层状结构
摘要：
蒙脱土是一种天然纳米材料,因对聚合物改性效果良好且价格低廉而受到广泛关注。无机蒙脱土易发生团聚现象,需对其进行有机化改性使其表现疏水特性。有机化蒙脱土可和沥青形成插层、剥离结构,有效提高沥青的高温性能和抗老化性能。文中分析了蒙脱土的结构与特性,概述了蒙脱土有机化所需改性剂和制备方法,阐述了有机蒙脱土改性沥青的作用与机理,并对有机蒙脱土改性沥青的未来研究方向进行了展望。
语种：
中文
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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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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：
<jats:p>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<jats:sub>x</jats:sub>), 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<jats:sub>x</jats:sub> (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<jats:sub>x</jats:sub> 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<jats:sub>x</jats:sub> 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</jats:p>
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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项目驱动的机械设计实践课程反向设计与研究
作者：
尹来容;张健;胡宏伟;毛聪;彭翠芳;...
期刊：
机械设计 ,2018年(S2):203-205 ISSN：1001-2354
作者机构：
长沙理工大学汽车与机械工程学院;[何志勇; 毛聪; 尹来容; 彭翠芳; 胡宏伟; 张健] 长沙理工大学
关键词：
机械设计;课程改革;反向设计
摘要：
根据机械设计类本科生实践课程内容与特点,对课程设计、毕业设计进行一体化反向设计,重点培养机械类本科生创新思维与解决工程问题的能力。根据CDIO与专业认证要求的"知识-能力-素质"体系,首先,整合机械原理与机械设计两门课程的课程设计,从课程理论知识体系上训练学生的创新思维与工程实践知识,其次,引入训练创新与工程实践的机械设计大作业,结合课程改革配备的专业指导教师,综合训练学生运用所学机械专业知识进行分析与解决问题的能力,进一步深入培养解决工程实际项目的能力,然后,基于课程大作业,开展机械类本科毕业选题工作。课程大作业选题来源分为学生根据自身兴趣选题、大学生科技立项、研究性学习与创新性实验项目、机械学科竞赛主题、专业指导教师横向/纵向项目等。
语种：
中文
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Performance of a turbine driven by train-induced wind in a tunnel
作者：
He, Kan;Gao, Guang-jun;Wang, Jia-bin;Fu, Min;Miao, Xiu-juan* ;...
期刊：
Tunnelling and Underground Space Technology ,2018年82(Dec.):416-427 ISSN：0886-7798
通讯作者：
Zhang, Jie;Miao, Xiu-juan
作者机构：
[He, Kan; Wang, Jia-bin; Fu, Min; Gao, Guang-jun; Zhang, Jie] Cent S Univ, Sch Traff & Transportat Engn, Minist Educ, Key Lab Traff Safety Track, Changsha, Hunan, Peoples R China.;[Miao, Xiu-juan] Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha, Hunan, Peoples R China.
通讯机构：
[Zhang, Jie; Miao, Xiu-juan] C;Cent S Univ, Sch Traff & Transportat Engn, Minist Educ, Key Lab Traff Safety Track, Changsha, Hunan, Peoples R China.;Changsha Univ Sci & Technol, Coll Automot & Mech Engn, Changsha, Hunan, Peoples R China.
关键词：
CFD;IDDES;Turbine;High-speed train;Tunnel
摘要：
A simulation of the turbine driven by a high-speed train-induced wind in the tunnel was performed using the IDDES method with the SST k-w turbulence model. A full-scale real train experiment was conducted, and the results from a previously published study were employed to verify the computational method and mesh used for the simulation of the flow fields around the train and the turbine. The results show that the differences between the experiment and simulation results are very small. Next, certain variations of the torque of the turbine, the vorticity, velocity, pressure and specific dissipation rate of the flow field around the turbine during the process of the train crossing a tunnel are analysed. The obtained results show that not only the wake of the tail car but also the flow around the head car exerts great influence on the turbine. Next, a series of comparative studies were performed. The relationship between the maximum torque of the turbine and the distances from the turbine to the entrance and the exit of the tunnel, which can be modelled as power functions, were proposed. It was observed that while the maximum torque of the turbine decreases when the length of a tunnel varies from 100 to 300 m, it increases with the increasing length of the tunnel for lengths between 300 and 800 m.
语种：
英文
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Recent progress in magnesium hydride modified through catalysis and nanoconfinement
作者：
Zhang, J.* ;Yan, S.;Qu, H.
期刊：
International Journal of Hydrogen Energy ,2018年43(3):1545-1565 ISSN：0360-3199
通讯作者：
Zhang, J.
作者机构：
[Qu, H.; Yan, S.; Zhang, J.] Changsha Univ Sci & Technol, Hunan Prov Key Lab Safety Design & Reliabil Techn, Changsha 410114, Hunan, Peoples R China.
通讯机构：
[Zhang, J.] C;Changsha Univ Sci & Technol, Hunan Prov Key Lab Safety Design & Reliabil Techn, Changsha 410114, Hunan, Peoples R China.
关键词：
Carbon;Catalysis;Enzyme kinetics;Hydrides;Hydrogen;Hydrogen storage;Magnesium;Nonmetals;Porous materials;Storage (materials);Thermodynamic stability;Thermodynamics;Environmental friendliness;Hydrogen storage properties;Magnesium hydride;Nanoconfinement effects;Nanoconfinements;Porous carbon materials;Solid-state hydrogen storage;Synergetic effect;Magnesium compounds
摘要：
Hydrogen is an ideal energy carrier because of its high chemical energy, environmental friendliness and renewability. In order to realize the safe, efficient and compact hydrogen storage, various solid-state hydrogen storage materials based on the physisorption or chemisorption of hydrogen have been developed over the past decades. Among them, magnesium hydride, MgH2, is identified as one of the most promising candidates due to its high hydrogen storage density, low cost and abundance of Mg element. However, the sluggish kinetics and high thermodynamic stability of MgH2 result in its high operation temperature and low hydrogen sorption rate, impeding its practical application. In this article, the recent progress in catalysis and nanoconfinement effects on the hydrogen storage properties of MgH2 is comprehensively reviewed. In particular, the synergetic roles of catalysis and nanoconfinement in MgH2 are highlighted. Furthermore, the future challenges and prospects of emerging research for MgH2 are discussed. It is suggested that the nonmetal-doped porous carbon materials could be a class of ideal additives to enhance the hydrogen storage properties of MgH2 by the synergetic effects of catalysis and nanoconfinement. © 2017 Hydrogen Energy Publications LLC
语种：
英文
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Effects of processing parameters on underfill defects in deep penetration laser welding of thick plates
作者：
Zhang, Mingjun* ;Tang, Kun;Zhang, Jian;Mao, Cong;Hu, Yongle;...
期刊：
International Journal of Advanced Manufacturing Technology ,2018年96(1-4):491-501 ISSN：0268-3768
通讯作者：
Zhang, Mingjun
作者机构：
[Hu, Yongle; Zhang, Jian; Zhang, Mingjun; Mao, Cong; Tang, Kun] Changsha Univ Sci & Technol, Educ Dept Hunan Prov, Key Lab Lightweight & Reliabil Technol Engn Vehic, Changsha 410114, Hunan, Peoples R China.;[Zhang, Mingjun] Changsha Univ Sci & Technol, Sch Energy & Power Engn, Key Lab Efficient & Clean Energy Utilizat, Changsha 410114, Hunan, Peoples R China.;[Zhang, Mingjun; Chen, Genyu] Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Peoples R China.
通讯机构：
[Zhang, Mingjun] C;[Zhang, Mingjun] H;Changsha Univ Sci & Technol, Educ Dept Hunan Prov, Key Lab Lightweight & Reliabil Technol Engn Vehic, Changsha 410114, Hunan, Peoples R China.;Changsha Univ Sci & Technol, Sch Energy & Power Engn, Key Lab Efficient & Clean Energy Utilizat, Changsha 410114, Hunan, Peoples R China.;Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Peoples R China.
关键词：
Fiber laser welding;Thick plate;Underfill defects;Processing parameter;Parameter optimization
摘要：
Underfill defect in welding affects not only the surface integrity but also the mechanical properties of workpiece. In this paper, the effects of the process parameters on underfill defects were investigated, and the deep penetration welding by a 10-kW fiber laser on 12-mm-thick stainless steel plates was used as the case study. The correlation of the processing parameters with the formation and elimination of underfill defects was analyzed and discussed. It was found that during the autogenous laser welding of thick plates, the direction of laser beam relative to gravity has a significant effect on the formation of underfill defects, and the preferable direction was an inclination angle of 60° with respect to the gravity. A negative defocus tended to obtain a full penetration weld with underfill and undercut defects. The higher the welding speed was, the lower the underfill depth was on the top surface. This phenomenon was observed on the full penetration welds at a defocus of − 10mm. With a negative defocus, it became feasible to optimize the combination of the focal position and the welding speed to achieve a satisfactory appearance of welds. In addition, a bottom-shielding ambience helped the full penetration in the laser welding process positively. © 2018, Springer-Verlag London Ltd., part of Springer Nature.
语种：
英文
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