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Monodisperse core-shell structured magnetic mesoporous aluminosilicate nanospheres with large dendritic mesochannels 被引量:12
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作者 Jianping Yang Dengke Shen +9 位作者 Yong Wei Wei Li Fan Zhang Biao Kong Shaohua Zhang Wei Teng Jianwei Fan Weixian Zhang Shixue Dou Dongyuan Zhao 《Nano Research》 SCIE EI CAS CSCD 2015年第8期2503-2514,共12页
The rational design and precise synthesis of multifunctional hybrid nanostructures with a tailored active core and a large, dendritic, modified mesoporous structured shell can promote catalysis, energy storage, and bi... The rational design and precise synthesis of multifunctional hybrid nanostructures with a tailored active core and a large, dendritic, modified mesoporous structured shell can promote catalysis, energy storage, and biological applications. Here, an oil-water biphase stratification coating strategy has been developed to prepare monodisperse magnetic dendritic mesoporous silica core-shell structured nano- spheres. These sophisticated Fe3O4@SiO2@dendritic-mSiO2 nanospheres feature large dendritic open pores (2.7 and 10.3 nm). Significantly, the silica shells can be converted into dendritic mesoporous aluminosilicate frameworks with unchanged porosity, a Si/Al molar ratio of 14, and remarkably strong acidic sites, through a post-synthesis approach. In addition, the resultant magnetic dendritic mesoporous aluminosilicate nanospheres exhibit outstanding properties and promising application in phosphate removal from wastewater. 展开更多
关键词 mesoporous materials core-shell structures ALUMINOSILICATES magnetic property surface acid
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大跨度自由双曲面清水混凝土密肋梁壳体结构施工技术 被引量:10
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作者 俞青 范立 +2 位作者 伍爱强 崔朝威 王林 《施工技术》 CAS 2020年第11期127-129,共3页
以琴台美术馆项目自由双曲面清水混凝土密肋梁壳体结构为背景,以达到清水混凝土成型观感效果为目标,研究双曲面结构的支撑体系及模板背楞体系,分析各类支撑及模板方案的优缺点,通过BIM技术在支撑体系上采用贝雷架+扣件式满堂架支撑体系... 以琴台美术馆项目自由双曲面清水混凝土密肋梁壳体结构为背景,以达到清水混凝土成型观感效果为目标,研究双曲面结构的支撑体系及模板背楞体系,分析各类支撑及模板方案的优缺点,通过BIM技术在支撑体系上采用贝雷架+扣件式满堂架支撑体系以及在模板背楞体系选用了定制弧形双钢管及定制变截面方木背楞方案,在安全性、经济性上都有良好效果,自由双曲面密肋梁壳体结构的质量控制达到清水混凝土的设计要求。 展开更多
关键词 混凝土 自由双曲面 清水混凝土 壳体结构 密肋梁 建筑信息模型 贝雷架
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半刚性连接网壳结构的有限元分析 被引量:6
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作者 李丽娟 车伟娴 +1 位作者 杨笑梅 刘锋 《空间结构》 CSCD 北大核心 2008年第1期43-49,39,共8页
建立了半刚性连接网壳结构的有限元模型,推导了考虑节点柔性的三维梁单元刚度矩阵,并对单元的固端力做了修正.在此基础上编写了相应的用户子程序UEL,该程序可以对半刚性连接的网壳结构进行节点位移和杆件内力的计算分析.算例验证了本文... 建立了半刚性连接网壳结构的有限元模型,推导了考虑节点柔性的三维梁单元刚度矩阵,并对单元的固端力做了修正.在此基础上编写了相应的用户子程序UEL,该程序可以对半刚性连接的网壳结构进行节点位移和杆件内力的计算分析.算例验证了本文所提出的模型及所编程序的正确性,最后分别对单层和双层网壳结构进行了半刚性节点分析,通过计算得到了一些有益于指导网壳工程设计的重要结论. 展开更多
关键词 网壳结构 半刚性连接 有限元模型 静力分析
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面向三维打印的壳状结构汽车及部件模型轻量化建模 被引量:7
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作者 王胜法 李宝军 +2 位作者 吕掌权 张龙飞 罗钟铉 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2015年第6期968-973,共6页
针对壳状模型轻量化设计和模拟问题,提出一种基于热扩散的壳状汽车模型轻量化方法,并利用三维打印在个性化方面的优势建立具有数值模型模拟、三维打印,以及工程验证的一整套汽车轻量化建模系统.首先对模型进行特征分析和提取;然后在给... 针对壳状模型轻量化设计和模拟问题,提出一种基于热扩散的壳状汽车模型轻量化方法,并利用三维打印在个性化方面的优势建立具有数值模型模拟、三维打印,以及工程验证的一整套汽车轻量化建模系统.首先对模型进行特征分析和提取;然后在给定特征约束和受力工况(外力)条件下,通过热扩散对受力分布进行模拟,并将模拟数值与模型厚度进行对应,得到初步优化模型;进一步,通过三维打印得到实体实验模型,并对实验模型进行工程受力验证,进而根据工程验证情况调整热扩散程度,使得优化模型的厚度更加逼近实际受力要求;最后通过循环迭代方式得到满足受力要求的重量优化模型.实验结果表明,该方法能够在满足实际受力情况下减重达30%,并大大缩短了壳状汽车模型研发周期,是有效且高效的. 展开更多
关键词 轻量化建模 壳状结构 热扩散 三维打印
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结构形态创构方法的工程应用 被引量:4
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作者 崔昌禹 姜宝石 崔国勇 《建筑钢结构进展》 2011年第6期9-18,共10页
结构形态创构方法是一种以数值计算为基础,运用数学、力学原理来追求力学合理,形式美观的建筑结构形态的方法。主要包括以下两种方法:"改进进化论方法"是模仿自然界的进化现象,通过进行"保留、淘汰、补充"的操作使... 结构形态创构方法是一种以数值计算为基础,运用数学、力学原理来追求力学合理,形式美观的建筑结构形态的方法。主要包括以下两种方法:"改进进化论方法"是模仿自然界的进化现象,通过进行"保留、淘汰、补充"的操作使结构体逐步进化并演变成合理结构的结构形态创构方法;而"高度调整方法"是基于有限元法,通过计算应变能对曲面高度的微分,并根据应变能变化的敏感程度对曲面高度进行调整,最终得到一个结构应变能最小的合理结构形态的自由曲面结构形态创构方法。该方法简单、实用,所得到的结构不但能保证实现建筑师的设计理念,也能保证结构的力学合理性。最终方案可以采用钢筋混凝土结构来实现,也可以用钢结构来实现。文中主要介绍了这两种结构形态创构方法的特点与实际工程中的应用方法,同时结合工程实例,详细分析了所得到的结构形态的力学性能。 展开更多
关键词 形态优化 结构优化 非线性方法 壳体结构
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靶丸X射线数字图像的轮廓分析及功率谱评价 被引量:4
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作者 赵学森 高党忠 +4 位作者 马小军 唐永建 张林 孙涛 董申 《强激光与粒子束》 EI CAS CSCD 北大核心 2010年第12期2925-2929,共5页
针对多层靶丸X射线数字图像的成像原理和轮廓边缘进行了理论分析;推导了由靶丸边缘特征点确定靶丸圆心和半径的精确最小二乘拟合算法;对于不同类型(阶跃状或屋顶状)的靶丸图像边缘,采用均化二阶微分算法或径向吸收强度最小二乘洛伦兹型... 针对多层靶丸X射线数字图像的成像原理和轮廓边缘进行了理论分析;推导了由靶丸边缘特征点确定靶丸圆心和半径的精确最小二乘拟合算法;对于不同类型(阶跃状或屋顶状)的靶丸图像边缘,采用均化二阶微分算法或径向吸收强度最小二乘洛伦兹型拟合寻峰算法获取亚像素精度的靶丸圆周轮廓边缘数据;应用快速傅里叶变换算法对靶丸圆周轮廓数据进行分析,获得了靶丸表面外轮廓或内轮廓模数-功率谱特征曲线。 展开更多
关键词 靶丸 射线数字图像 轮廓分析 功率谱 image X-ray ICF shell evaluation power spectrum analysis 快速傅里叶变换算法 最小二乘拟合算法 轮廓边缘 亚像素精度 圆周 寻峰算法 吸收强度 微分算法 图像边缘 特征曲线
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板壳结构非线性随机有限元法研究 被引量:5
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作者 王庆 姚竞争 《工程力学》 EI CSCD 北大核心 2013年第12期286-292,共7页
采用摄动随机有限元法研究了具有随机参数的板壳结构大挠度动力响应问题。基于Mindlin-Reissner板理论,采用全量Lagrangian法推导了具有板壳结构的大变形、大转动的动力响应有限元列式;通过基于等参变换的局部模型对随机场进行离散,结... 采用摄动随机有限元法研究了具有随机参数的板壳结构大挠度动力响应问题。基于Mindlin-Reissner板理论,采用全量Lagrangian法推导了具有板壳结构的大变形、大转动的动力响应有限元列式;通过基于等参变换的局部模型对随机场进行离散,结合摄动技术,建立了基于摄动技术的增量形式的随机有限元列式,计算结果与Monte-Carlo法相比较表明了该方法的有效性和精确性。通过该方法,为进一步进行结构可靠性分析提供了依据和方便。 展开更多
关键词 几何非线性 板壳结构 摄动技术 随机有限元法 随机场
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One-dimensional ZnS-based Hetero-,Core/shell and Hierarchical Nanostructures 被引量:3
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作者 Ujjal K.Gautam Yoshio BANDO Dmitri GOLBERG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2008年第4期520-528,共9页
A focus of the current nanotechnology has shifted from routine fabrication of nanostructures to designing functional electronic devices and realizing their immense potentials for applications. Due to infusion of multi... A focus of the current nanotechnology has shifted from routine fabrication of nanostructures to designing functional electronic devices and realizing their immense potentials for applications. Due to infusion of multi-functionality into a single system, the utilization of hetero-, core/shell and hierarchical nanostructures has become the key issue for building such devices. ZnS, due to its direct wide bandgap, high index of refraction, high transparency in the visible range and intrinsic polarity, is one of the most useful semiconductors for a wide range of electronics applications. This article provides a dense review of the state-of-the-art research activities in one-dimensional (1D) ZnS-based hetero-, core/shell and hierarchical nanostructures. The particular emphasis is put on their syntheses and applications. 展开更多
关键词 HETEROstructures Core/shell Hierarchical structures ZNS NANODEVICES
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Ultra-thin layer structured anodes for highly durable Iow-Pt direct formic acid fuel cells 被引量:4
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作者 RongyueWang Jianguo Liu +7 位作者 Pan Liu Xuanxuan Bi Xiuling Yan Wenxin Wang Yifei Meng Xingbo Ge Mingwei Chen Yi Ding 《Nano Research》 SCIE EI CAS CSCD 2014年第11期1569-1580,共12页
Direct formic acid fuel cells (DFAFCs) allow highly efficient low temperature conversion of chemical energy into electricity and are expected to play a vital role in our future sustainable society. However, the mass... Direct formic acid fuel cells (DFAFCs) allow highly efficient low temperature conversion of chemical energy into electricity and are expected to play a vital role in our future sustainable society. However, the massive precious metal usage in current membrane electrode assembly (MEA) technology greatly inhibits their actual applications. Here we demonstrate a new type of anode constructed by confining highly active nanoengineered catalysts into an ultra-thin catalyst layer with thickness around 100 nm. Specifically, an atomic layer of platinum is first deposited onto nanoporous gold (NPG) leaf to achieve high utilization of Pt and easy accessibility of both reactants and electrons to active sites. These NPG-Pt core/shell nanostructures are further decorated by a sub-monolayer of Bi to create highly active reaction sites for formic acid electro-oxidation. Thus obtained layer-structured NPG-Pt-Bi thin films allow a dramatic decrease in Pt usage down to 3 ~tg.cm-2, while maintaining very high electrode activity and power performance at sufficiently low overall precious metal loading. Moreover, these electrode materials show superior durability during half-year test in actual DFAFCs, with remarkable resistance to common impurities in formic acid, which together imply their great potential in applications in actual devices. 展开更多
关键词 direct formic acid fuel cells low-Pt loading core/shell structures nanoporous gold DEALLOYING
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Coaxial electrohydrodynamic printing of core–shell microfibrous scaffolds with layer-specific growth factors release for enthesis regeneration
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作者 Lang Bai Meiguang Xu +10 位作者 Zijie Meng Zhennan Qiu Jintao Xiu Baojun Chen Qian Han Qiaonan Liu Pei He Nuanyang Wen Jiankang He Jing Zhang Zhanhai Yin 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第5期220-238,共19页
The rotator cuff tear has emerged as a significant global health concern.However,existing therapies fail to fully restore the intricate bone-to-tendon gradients,resulting in compromised biomechanical functionalities o... The rotator cuff tear has emerged as a significant global health concern.However,existing therapies fail to fully restore the intricate bone-to-tendon gradients,resulting in compromised biomechanical functionalities of the reconstructed enthesis tissues.Herein,a tri-layered core–shell microfibrous scaffold with layer-specific growth factors(GFs)release is developed using coaxial electrohydrodynamic(EHD)printing for in situ cell recruitment and differentiation to facilitate gradient enthesis tissue repair.Stromal cell-derived factor-1(SDF-1)is loaded in the shell,while basic fibroblast GF,transforming GF-beta,and bone morphogenetic protein-2 are loaded in the core of the EHD-printed microfibrous scaffolds in a layer-specific manner.Correspondingly,the tri-layered microfibrous scaffolds have a core–shell fiber size of(25.7±5.1)μm,with a pore size sequentially increasing from(81.5±4.6)μm to(173.3±6.9)μm,and to(388.9±6.9μm)for the tenogenic,chondrogenic,and osteogenic instructive layers.A rapid release of embedded GFs is observed within the first 2 d,followed by a faster release of SDF-1 and a slightly slower release of differentiation GFs for approximately four weeks.The coaxial EHD-printed microfibrous scaffolds significantly promote stem cell recruitment and direct their differentiation toward tenocyte,chondrocyte,and osteocyte phenotypes in vitro.When implanted in vivo,the tri-layered core–shell microfibrous scaffolds rapidly restored the biomechanical functions and promoted enthesis tissue regeneration with native-like bone-to-tendon gradients.Our findings suggest that the microfibrous scaffolds with layer-specific GFs release may offer a promising clinical solution for enthesis regeneration. 展开更多
关键词 coaxial electrohydrodynamic printing core-shell structures microfibrous scaffolds growth factors enthesis regeneration
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Catechol-Formaldehyde Resin Coated CdS Core-Shell Composite as Robust Photocatalyst for Long-Term Sustainable Artificial Photosynthesis of H_(2)O_(2)
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作者 Yuexin Xiang Zhinan Xia +3 位作者 Wanchao Hu Cuiyan Tong Yang Xiao Changli Lu 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2024年第17期1975-1985,共11页
Catechol-formaldehyde resin(CFR)is very attractive for H_(2)O_(2) production via the catalytic process.However,the H2O2 formation is accompanied by the oxidation of catechol groups to o-benzoquinone groups on CFR,whic... Catechol-formaldehyde resin(CFR)is very attractive for H_(2)O_(2) production via the catalytic process.However,the H2O2 formation is accompanied by the oxidation of catechol groups to o-benzoquinone groups on CFR,which will cause irreversible damage to CFR and greatly limit its long-term stable catalytic activity.Herein,CdS/CFR composite photocatalyst with a core-shell structure was synthesized by hydrothermal method.The photogenerated electrons of Cds are used as a powerful driving force for the reversible redox conversion between catechol groups and o-benzoquinone groups on the CFR. 展开更多
关键词 Hydrogen peroxide Photocatalysis Catechol-formaldehyde resin CDS Core-shell structures Oxygen reduction reaction Charge transfer Heterogeneous catalysis
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Synergistic Effect of Core/Shell‑Structured Composite Fibers:Efficient Recovery of Rare‑Earth Elements from Spent NdFeB Permanent Magnets
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作者 Youngkyun Jung Yun Lee +1 位作者 Su‑Jin Yoon Jae‑Woo Choi 《Advanced Fiber Materials》 SCIE EI CAS 2024年第6期1729-1745,共17页
NdFeB magnets are third-generation permanent magnets that are employed as indispensable components in various industries.Notably,rare-earth elements(REEs)such as Dy and Nd must be efficiently recovered from end-of-lif... NdFeB magnets are third-generation permanent magnets that are employed as indispensable components in various industries.Notably,rare-earth elements(REEs)such as Dy and Nd must be efficiently recovered from end-of-life magnets to enable resource circulation and reinforce unstable supply chains.To that end,this paper reports synergistically performing core/shell-structured composite fibers(CSCFs)containing sodium polyacrylate and nanoporous zeolitic imidazolate framework-8(NPZIF-8)nanocrystals as a readily recoverable adsorbent with an exceptional REE-adsorbing ability.The CSCF core forms an NPZIF-8 nanocrystal shell on the fiber surface as well as draws REEs using its dense sodium carboxylate groups into the NPZIF-8 nanocrystal lattice with high specific surface area.The CSCFs exhibit significantly higher maximum adsorption capacities(468.60 and 435.13 mg·g-1)and kinetic rate constants(2.02 and 1.92 min-1)for the Nd3+and Dy3+REEs than those of previously reported REE adsorbents.Additionally,the simple application of the CSCFs to an adsorption reactor considerably mitigates the adsorbent-shape-induced pressure drop,thereby directly influencing the energy efficiency of the recovery.Moreover,the high REE-recovery ability,tractability,and recyclability of the CSCFs offers a pragmatic pathway to achieving cost-effective REE recovery.Overall,this study provides new insights into designing synergistically performing core/shell architectures for feasible REE recovery. 展开更多
关键词 Core/shell structures Fibrous adsorbents Synergistic adsorption Metal resource recovery Pressure drop Rare-earth elements
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A novel Ag/ZnO core-shell structure for efficient sterilization synergizing antibiotics and subsequently removing residuals
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作者 Wenmei Han Wenli Wang +4 位作者 Jie Fan Runping Jia Xuchun Yang Tong Wu Qingsheng Wu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第2期366-377,共12页
The massive use of antibiotics has led to the aggravation of bacterial resistance and also brought environmental pollution problems.This poses a great threat to human health.If the dosage of antibiotics is reduced by ... The massive use of antibiotics has led to the aggravation of bacterial resistance and also brought environmental pollution problems.This poses a great threat to human health.If the dosage of antibiotics is reduced by increasing its bactericidal performance,the emergence of drug resistance is certainly delayed,so that there's not enough time for developing drug resistance during treatment.Therefore,we selected typical representative materials of metal Ag and semiconductor ZnO nano-bactericides to design and synthesize Ag/ZnO hollow core-shell structures(AZ for short).Antibiotics are grafted on the surface of AZ through rational modification to form a composite sterilization system.The research results show that the antibacterial efficiency of the composite system is significantly increased,from the sum(34.7%+22.8%-57.5%)of the antibacterial efficiency of AZ and gentamicin to 80.2%,net synergizes 22.7%,which fully reflects the effect of 1+1>2.Therefore,the dosage of antibiotics can be drastically reduced in this way,which makes both the possibility of bacterial resistance and medical expenses remarkably decrease.Subsequently,residual antibiotics can be degraded under simple illumination using AZ-self as a photocatalyst,which cuts off the path of environmental pollution.In short,such an innovative route has guiding significance for drug resistance. 展开更多
关键词 Ag/ZnO hollow Core-shell structures ANTIBIOTICS GENTAMYCIN Synergistic sterilization PHOTODEGRADATION
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Full-Scale Isogeometric Topology Optimization of Cellular Structures Based on Kirchhoff-Love Shells
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作者 Mingzhe Huang Mi Xiao +3 位作者 Liang Gao Mian Zhou Wei Sha Jinhao Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2479-2505,共27页
Cellular thin-shell structures are widely applied in ultralightweight designs due to their high bearing capacity and strength-to-weight ratio.In this paper,a full-scale isogeometric topology optimization(ITO)method ba... Cellular thin-shell structures are widely applied in ultralightweight designs due to their high bearing capacity and strength-to-weight ratio.In this paper,a full-scale isogeometric topology optimization(ITO)method based on Kirchhoff-Love shells for designing cellular tshin-shell structures with excellent damage tolerance ability is proposed.This method utilizes high-order continuous nonuniform rational B-splines(NURBS)as basis functions for Kirchhoff-Love shell elements.The geometric and analysis models of thin shells are unified by isogeometric analysis(IGA)to avoid geometric approximation error and improve computational accuracy.The topological configurations of thin-shell structures are described by constructing the effective density field on the controlmesh.Local volume constraints are imposed in the proximity of each control point to obtain bone-like cellular structures.To facilitate numerical implementation,the p-norm function is used to aggregate local volume constraints into an equivalent global constraint.Several numerical examples are provided to demonstrate the effectiveness of the proposed method.After simulation and comparative analysis,the results indicate that the cellular thin-shell structures optimized by the proposed method exhibit great load-carrying behavior and high damage robustness. 展开更多
关键词 Cellular thin-shell structures isogeometric analysis full-scale topology optimization Kirchhoff–Love shells
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Constructing hierarchical arrays with core-shell metal oxides@metal coordination polymers for efficient and stable overall water splitting
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作者 Shuai Qi Jinlian Liao +7 位作者 Kunzhong Chen Senkai Li Jinwen Zhao Tianchi Huang Na Meng Hengpan Yang Qi Hu Chuanxin He 《Nano Research》 SCIE EI CSCD 2024年第6期4882-4888,共7页
Developing non-precious metal-based bifunctional electrocatalysts capable for both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)is essential to achieve efficient water electrolysis for mass hydrog... Developing non-precious metal-based bifunctional electrocatalysts capable for both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)is essential to achieve efficient water electrolysis for mass hydrogen production,however it remains challenging.Here,we report the synthesis of hierarchical nanorod arrays comprising core-shell structured P-doped NiMoO4@NiFe-coordination polymer(denoted as P-NiMoO4@NiFeCP)as bifunctional electrocatalysts for water electrolysis.Furthermore,we systematically investigate the influence of NiFeCP shell thickness on electrocatalytic activity,manifesting the presence of strong interfacial synergetic effect between P-NiMoO4 and NiFeCP for boosting both the HER and OER.With advantageous hierarchical architectures and unique core-shell structures,optimized P-NiMoO_(4)@NiFeCP-7.3(7.3 is the shell thickness in nm)requires overpotentials of merely 256 and 297 mV to yield a current density of 1000 mA·cm^(−2)for the HER and OER in 1 M KOH,respectively.More importantly,it can serve as a bifunctional electrocatalyst for efficient and sustainable overall water electrolysis,delivering large current densities of 500 and 1000 mA·cm^(−2)at low cell voltages of 1.804 and 1.865 V,along with high stability of over 500 h at 1000 mA·cm−2,demonstrating the great potential of this electrocatalyst towards practical applications. 展开更多
关键词 hydrogen evolution reaction oxygen evolution reaction overall water splitting non-precious metal-based electrocatalysts core-shell structures
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Confined nanospace pyrolysis: A versatile strategy to create hollow structured porous carbons 被引量:3
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作者 Rui-Ping Zhang Wen-Cui Li +1 位作者 Guang-Ping Hao An-Hui Lu 《Nano Research》 SCIE EI CSCD 2021年第9期3159-3173,共15页
Confined nanospace pyrolysis(CNP)has attracted increasing attention as a general strategy to prepare task-specific hollow structured porous carbons(HSPCs)in the past decade.The unique advantages of the CNP strategy in... Confined nanospace pyrolysis(CNP)has attracted increasing attention as a general strategy to prepare task-specific hollow structured porous carbons(HSPCs)in the past decade.The unique advantages of the CNP strategy include its outstanding ability in control of the monodispersity,porosity and internal cavity of HSPCs.As a consequence,the obtained HSPCs perform exceptionally well in applications where a high dispersibility and tailored cavity are particularly required,such as drug delivery,energy storage,catalysis and so on.In this review,the fundamentals of the CNP strategy and its advances in structural alternation is first summarized,then typical applications are discussed by exemplifying specific synthesis examples.In addition,this review offers insights into future developments for advanced task-specific hollow structured porous materials prepared by the CNP strategy. 展开更多
关键词 confined nanospace pyrolysis hollow structures carbon materials core-shell structures DISPERSIBILITY
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采用有限质点法的薄壳动力非线性行为分析 被引量:3
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作者 杨超 罗尧治 郑延丰 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2019年第6期1019-1030,共12页
基于有限质点法原理和K-L经典薄壳理论,构造具有大位移大转动分析能力的薄壳离散质点模型,推导表述基本控制方程与公式.对于质点位移以及壳元的变形和内力,均按照面内拉压和面外弯扭两部分进行拆分与叠加,并通过物理方式的虚拟运动依次... 基于有限质点法原理和K-L经典薄壳理论,构造具有大位移大转动分析能力的薄壳离散质点模型,推导表述基本控制方程与公式.对于质点位移以及壳元的变形和内力,均按照面内拉压和面外弯扭两部分进行拆分与叠加,并通过物理方式的虚拟运动依次分离出与薄膜刚度和弯曲刚度相关的纯变形,进而在局部变形坐标系下求解面外变形相对应的质点内力和内力矩,建立质点切平面外转角的变步长显式时间积分式,并对质点质量、时间步长、阻尼等关键参数取值给出建议.在此基础上引入材料非线性应力修正算法,实现对薄壳弹塑性大应变动力非线性行为的模拟,并通过典型算例验证方法及程序的有效性和正确性. 展开更多
关键词 薄壳结构 有限质点法 非线性 动力 结构复杂行为
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采用ANSYS(隐式)、LS-DYNA(显式)和两者共同分析法对薄壁结构进行有限元极限荷载分析 被引量:1
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作者 Wilhelm Rust Karl Schweizerhof 《钢结构》 2008年第9期79-80,共2页
在分析了采用ANSYS隐式有限元分析和LS-DYNA显式分析的一般情况之后,得到显式时间积分法对准静态极限荷载分析进行瞬态分析的时间和方式。然后将重点关注隐式分析的优点,探讨如何更有效地将ANSYS和LS-DYNA进行组合,使其能具有更好的瞬... 在分析了采用ANSYS隐式有限元分析和LS-DYNA显式分析的一般情况之后,得到显式时间积分法对准静态极限荷载分析进行瞬态分析的时间和方式。然后将重点关注隐式分析的优点,探讨如何更有效地将ANSYS和LS-DYNA进行组合,使其能具有更好的瞬态分析效果。最后,概述了模型的离散化,控制方案的选择,缺陷的考虑和结果校核。 展开更多
关键词 极限荷载分析 稳定问题 缺陷 准静态动力 显性时间积分 塑性材料 壳结构
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冰区船外板结构冰载荷监测识别方法及统计分析研究现状 被引量:3
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作者 孔帅 田于逵 +2 位作者 赵桥生 王迎晖 季顺迎 《船舶工程》 CSCD 北大核心 2022年第6期1-9,52,共10页
冰区船外板结构冰载荷在时频特征、时空演化规律和统计特性等方面具有极强的差异性,可能会导致结构遭到严重损毁或疲劳破坏,通过实船监测识别能较为直接有效地揭示冰载荷特征。结合典型实船的冰载荷测量系统,对其核心监测技术进行归纳,... 冰区船外板结构冰载荷在时频特征、时空演化规律和统计特性等方面具有极强的差异性,可能会导致结构遭到严重损毁或疲劳破坏,通过实船监测识别能较为直接有效地揭示冰载荷特征。结合典型实船的冰载荷测量系统,对其核心监测技术进行归纳,比较分析影响系数矩阵、时域反卷积和支持向量机等3种冰载荷识别方法,汇总冰载荷峰值提取、峰值分布拟合、峰值离散特性和冰力周期分布拟合等统计研究进展情况。基于冰区船冰载荷监测发展趋势,提出需进一步研究的问题。 展开更多
关键词 冰区船 外板结构 冰载荷 识别方法 现场测量 统计分析
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梁壳组合结构的一种非线性有限元计算方法 被引量:1
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作者 詹福良 杨嘉陵 黎在良 《航空学报》 EI CAS CSCD 北大核心 2001年第3期281-283,共3页
提出了梁壳垂直组合结构在有限元计算中存在的问题 ,并以几何大变形问题为依托提供了解决该问题的计算原理和有限元方法。数值算例证明了该理论和方法的正确性。该法不仅适用于梁壳组合结构的大变形非线性计算 ,也适用于静动力小变形问... 提出了梁壳垂直组合结构在有限元计算中存在的问题 ,并以几何大变形问题为依托提供了解决该问题的计算原理和有限元方法。数值算例证明了该理论和方法的正确性。该法不仅适用于梁壳组合结构的大变形非线性计算 ,也适用于静动力小变形问题的线弹性分析计算。 展开更多
关键词 板壳 组合结构 数值模拟 非线性有限元 转动自由度 航空 航天工程
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