检索结果-南通市图书馆

Bio-inspired self-folding strategy to break the trade-off between strength and ductility in carbon-nanoarchitected materials

在线全文

学校读者我要写书评

暂无评论

npj Computational Materials 2020年第1期6卷 1558-1564页

作者： Xiangzheng Jia Ze Liu enlai gao Department of Engineering Mechanics School of Civil EngineeringWuhan UniversityWuhanHubei 430072China

Graphene possesses extraordinary mechanical,electronic,and thermal properties,thus making it one of the most promising building blocks for constructing macroscopic high performance and multifunctional ***,the common material strength–ductility paradox also appears in the carbon-nanoarchitected materials and some of the key mechanical performance,for example,the tensile strength of graphene-based materials,are still far lower than that of *** by the exceptional mechanical performance of silk protein benefiting from the conformations of folded structures as well as their transitions,this work proposed a topological strategy to yield graphene-based materials with ultrahigh ductility while maintaining decent tensile strength by self-folding graphene *** drastically improved mechanical performance of graphene-based materials is attributed to the exploitation of shearing,sliding,and unfolding deformation at the self-folded *** dynamics simulations show that both modulating self-folded length and engineering interface interaction can effectively control the strength,ductility,and the ductile failure of van der Waals interfaces among the self-folded structures,where interfacial shearing,sliding,and unfolding open channels to dissipate mechanical *** on the insights into the atomic-scale deformation by molecular dynamics simulations,the underlying mechanism of deformation and failure of these materials is finally discussed with a continuum mechanics-based *** findings bring perceptive insights into the microstructure design of strong-yet-ductile materials for load-bearing engineering applications.

关键词： strength ductility deformation

Microstructural ordering of nanofibers in flow-directed assembly

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2019年第9期62卷 1545-1554页

作者： gao enlai WANG ShiJun DUAN ChuanHua XU ZhiPing Applied Mechanics Laboratory Department of Engineering Mechanicsand Center for Nano and Micro MechanicsTsinghua UniversityBeijing 100084China Department of Mechanical Engineering Boston UniversityBoston MA 02215USA Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and EngineeringSouthwest Jiaotong UniversityChengdu 611756China

Fabrication of highly ordered and dense nanofibers assemblies is of key importance for high-performance and multi-functional material and device applications. In this work, we design an experimental approach in silico, where shear flow and solvent evaporation are applied to tune the alignment, overlap of nanofibers, and density of the assemblies. Microscopic dynamics of the process are probed by dissipative particle dynamics simulations, where hydrodynamic and thermal fluctuation effects are fully modeled. We find that microstructural ordering of the assembled nanofibers can be established within a specific range of the Peclet numbers and evaporation rates, while the properties of nanofibers and their interaction are crucial for the local stacking order. The underlying mechanisms are elucidated by considering the competition between hydrodynamic coupling and thermal fluctuation. Based on these understandings, a practical design of flow channels for nanofiber assembly with promising mechanical performance is outlined.

关键词： nanofiber nanostructured assemblies shear flow solvent evaporation alignment stacking order densification dissipative particle dynamics

High-performance phosphorene electromechanical actuators

在线全文

学校读者我要写书评

暂无评论

npj Computational Materials 2020年第1期6卷 1439-1445页

作者： Bozhao Wu Hui-Xiong Deng Xiangzheng Jia Langquan Shui enlai gao Ze Liu Department of Engineering Mechanics School of Civil EngineeringWuhan UniversityWuhanHubei 430072China State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China

Phosphorene,a two-dimensional material that can be exfoliated from black phosphorus,exhibits remarkable mechanical,thermal,electronic,and optical *** this work,we demonstrate that the unique structure of pristine phosphorene endows this material with exceptional quantum-mechanical performance by using first-principles calculations.

关键词： performance exceptional ene

Simultaneously enhanced interfacial shear strength and tensile strength of heterocyclic aramid fiber by graphene oxide

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2023年第10期16卷 12286-12293页

作者： Ziyi Zhang Xiangzheng Jia Chun Li Lanying Li Yeye Wen Zhenfei gao Jiangwei Zhang enlai gao Kun Jiao Jin Zhang College of Science China University of Petroleum(Beijing)Beijing 102249China Beijing National Laboratory for Molecular Sciences School of Materials Science and EngineeringCollege of Chemistry and Molecular EngineeringBeijing Science and Engineering Center for NanocarbonsPeking UniversityBeijing 100871China Beijing Graphene Institute(BGI) Beijing 100095China Department of Engineering Mechanics School of Civil EngineeringWuhan UniversityWuhan 430072China China Bluestar Chengrand Chemical Co. Ltd.Chengdu 610041China Science Center of Energy Material and Chemistry College of Chemistry and Chemical EngineeringInner Mongolia UniversityHohhot 010021China

Heterocyclic aramid fibers,a typical kind of high-performance fibers,have been widely used in aerospace and protection fields because of their excellent mechanical ***,the application of heterocyclic aramid fibers as a reinforcement is hindered by the weak interfacial combination with matrix materials,especially *** strategies enhancing the interfacial shear strength(IFSS)usually decrease the tensile ***,simultaneous enhancement of both mechanical properties remains a ***,we report a novel heterocyclic aramid fiber with high interfacial shear strength(49.3 MPa)and tensile strength(6.27 GPa),in which 4,4′-diamino-2′-chlorobenzanilide(DABA-Cl)and a small amount of graphene oxide(GO)are introduced through in-situ *** bonds andπ–πinteraction between GO and polymer chains trigger the enhancement in crystallinity,orientation,and lateral interaction of the fibers,thus improving the tensile strength and interfacial shear strength of the ***,the interfacial interaction between fiber and epoxy is enhanced due to the improvement of the surface polarity of the fibers caused by ***,a method to improve both tensile strength and interfacial shear strength of heterocyclic aramid fibers was found by introducing GO and DABA-Cl,which may provide guidance for the design and preparation of other high-performance fibers.

关键词： heterocyclic aramid fibers graphene oxide(GO) 4 4′-diamino-2′-chlorobenzanilide(DABA-Cl) interfacial shear strength tensile strength

Elasticity-based-exfoliability measure for high-throughput computational exfoliation of two-dimensional materials

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

npj Computational Materials 2021年第1期7卷 1941-1948页

作者： Xiangzheng Jia Qian Shao Yongchun Xu Ruishan Li Kai Huang Yongzhe Guo Cangyu Qu enlai gao Department of Engineering Mechanics School of Civil EngineeringWuhan UniversityWuhanHubei 430072China Institute of Superlubricity Technology.Research Institute of Tsinghua University in Shenzhen Shenzhen 518057China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China

Two-dimensional(2D)materials are promising candidates for uses in next-generation electronic and optoelectronic ***,only a few high-quality 2D materials have been mechanically exfoliated to *** of the critical issues is that the exfoliability of 2D materials from their bulk precursors is *** assess the exfoliability of potential 2D materials from their bulk counterparts,we derived an elasticity-based-exfoliability measure based on an exfoliation mechanics *** proposed measure has a clear physical meaning and is universally applicable to all material *** used this measure to calculate the exfoliability of 10,812 crystals having a first-principles calculated elastic *** setting the threshold values for easy and potential exfoliation based on already-exfoliated materials,we predicted 58 easily exfoliable bulk crystals and 90 potentially exfoliable bulk crystals for 2D *** evidence,a topology-based algorithm indicates that there is no interlayer bondingtopology for 93%predicted exfoliable bulk crystals,and the analysis on packing ratios shows that 99%predicted exfoliable bulk crystals exhibit a relatively low packing ratio ***,literature survey shows that 34 predicted exfoliable bulk crystals have been experimentally exfoliated into 2D *** addition,the characteristics of these predicted 2D materials were discussed for practical use of such materials.

关键词： materials packing dimensional

基于不同梁模型的弯曲变形分析与实验教学探讨

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

实验力学 2021年第5期36卷 617-626页

作者：王正直颜朔庚王琨高恩来税朗泉何勇黄凯武汉大学土木建筑工程学院工程力学系湖北武汉430072

梁的弯曲变形是基础力学的核心内容之一,以往实验教学中的变形分析通常基于Euler-Bernoulli梁模型进行,而对工程中常见的Timoshenko梁涉及较少,这种变形模式的单一性和局限性教学无疑落后于当前力学学科人才培养的发展趋势。为了使本科... 详细信息

梁的弯曲变形是基础力学的核心内容之一,以往实验教学中的变形分析通常基于Euler-Bernoulli梁模型进行,而对工程中常见的Timoshenko梁涉及较少,这种变形模式的单一性和局限性教学无疑落后于当前力学学科人才培养的发展趋势。为了使本科生深入理解梁弯曲行为并掌握更为全面的实验技术,本文通过理论分析和模型优化,研发并搭建了一套可同时验证两种梁模型(即Euler-Bernoulli梁和Timoshenko梁)的高精度实验平台。通过位移校准和精确变形测量,验证了两种梁模型的精度和适用条件。实验发现,加载处的跨高比小于5时,实测值与Timoshenko梁的理论解非常吻合;加载处的跨高比大于5时,两种梁模型的差异可以忽略,Euler-Bernoulli梁模型可用于描述弯曲变形。基于该实验平台,编排设计了力学教学实验并进行了初步实践和评估,该课程阐明了剪切变形对梁弯曲变形的影响,使学生对梁模型的类型与相应假定的理解得到了加深;互动式教学和自主设计测量全方位提高了学生解决实际问题的能力。

关键词：基础力学梁模型悬臂梁实验平台教学实验

Iron-doped Ag/Ni_(2)(CO_(3))(OH)_(2)hierarchical microtubes for highly efficient water oxidation

在线全文

学校读者我要写书评

暂无评论

Carbon Energy 2022年第5期4卷 939-949页

作者： Huiwen Zhang Shuxuan Liu enlai Hu Yunfei Yang Huimin Zhang Yuting Zhu Lijing Yan Xuehui gao Jing Zhang Zhan Lin Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Department of ChemistryZhejiang Normal UniversityJinhuaChina College of Materials and Chemistry China Jiliang UniversityHangzhouChina Guangzhou Key Laboratory of Clean Transportation Energy Chemistry Guangzhou Higher Education Mega CenterGuangdong University of TechnologyGuangzhouGuangdongChina

Doping of foreign atoms and construction of unique structures are considered as effective approaches to design high-activity and strongdurability ***,we report Fe-doped nickel hydroxide carbonate hierarchical microtubes with Ag nanoparticles(denoted Ag/NiFeHC HMTs)through hydrolysis precipitation *** tests and density functional theory calculations reveal that Fe doping can tune the electron configuration to enhance the conductivity,markedly improve the electrochemical surface area to expose more active sites,and act as reactive centers to lower the free energy of the rate determination *** addition,the unique hierarchical structure can also offer active sites and excellent cycling *** from these advantages,the as-obtained Ag/NiFeHC HMTs show excellent oxygen evolution reaction activity,with an overpotential of 208 mV at 10 mA cm^(−2)in 1.0M ***,it could achieve long-term stability at a current density of 20 mA cm^(−2)for 24 h.

关键词： density functional theory Fe doping Ni2(CO3)(OH)2 hierarchical microtubes water oxidation reaction

基于锌空电池探究能斯特方程影响因素及固态锌空电池的应用

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

大学化学 2024年第5期39卷 98-107页

作者：高文琪范晓艳王飞翔傅镯君张璟胡恩来宫培军浙江师范大学化学与材料科学学院浙江金华321019

针对无机化学中能斯特方程的教学难点,本实验引入紧跟科学前沿的锌空电池为教学模型,通过改变电极氧化型和还原型浓度来探究能斯特方程影响因素,加深学生对于电化学过程的理解。同时将柔性电子技术引入实验课堂,以安全环保的卡拉胶作为... 详细信息

针对无机化学中能斯特方程的教学难点,本实验引入紧跟科学前沿的锌空电池为教学模型,通过改变电极氧化型和还原型浓度来探究能斯特方程影响因素,加深学生对于电化学过程的理解。同时将柔性电子技术引入实验课堂,以安全环保的卡拉胶作为固态电解质,引导学生学习、搭建固态锌空电池,并对其进行电池电压与弯曲角度的性能测试。此外,培养学生创造力,自主设计搭建多形态固态锌空电池,并对用电器进行供电。本实验紧密结合基础电化学知识,密切联系科研前端技术,使学生在加深对能斯特方程理解的同时,能够认识和制作柔性电子器件,激发学生对电化学课程的学习兴趣,且教学成本低、效果好。

关键词：能斯特方程锌空电池柔性电子固态电解质

维普期刊数据库博看期刊

各民族互嵌式发展:内涵要素、现实问题及路径选择

在线全文

学校读者我要写书评

暂无评论

广西民族大学学报（哲学社会科学版） 2024年第3期46卷 36-44页

作者：高永久杨龙文南开大学周恩来政府管理学院南开大学民族事务研究中心(天津市铸牢中华民族共同体意识研究基地)

在中国式现代化进程中,各民族互嵌式发展是民族互嵌概念在发展维度上的深化。各民族互嵌式发展是指各民族依赖于一定的空间、资源、理念、环境、发展等要素,通过双向流动的联通渠道而相互嵌入,并在物质与精神相互协调的发展演进中最终... 详细信息

在中国式现代化进程中,各民族互嵌式发展是民族互嵌概念在发展维度上的深化。各民族互嵌式发展是指各民族依赖于一定的空间、资源、理念、环境、发展等要素,通过双向流动的联通渠道而相互嵌入,并在物质与精神相互协调的发展演进中最终实现共同富裕的过程。“空间-资源-理念-环境-发展”构成了五位一体的各民族互嵌式发展结构要素解释框架。基于这一解释框架,当前各民族互嵌式发展面临着一些现实问题。这包括民族人口流动单向性特征仍较为明显、各民族共享资源配置效度还不够高、对互嵌式发展理念认知不足、各民族互嵌式氛围环境存在干扰因素、各民族共同富裕的互嵌性基础仍不充分等。对此,要围绕搭建互嵌式空间场域、供给互嵌式公共资源、形塑互嵌式现代理念、维护互嵌式氛围环境、实现互嵌式繁荣发展这五类结构要素发力。通过在市场驱动与有序引导中优化民族双向流动格局,为各民族提供公平性、优质性、共享性公共服务,在包容互助中凝聚对中华民族共同体的强烈认同,以安全稳定建设和营商环境建设强化内外部保障,以互补协作和共同团结奋斗实现各民族共同富裕,从而推进各民族互嵌式发展。

关键词：各民族互嵌式发展民族互嵌共同富裕民族交往交流交融双向流动