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Finite element prediction on the response of non-uniformly arranged pile groups considering progressive failure of pile-soil system

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Frontiers of Structural and Civil Engineering 2020年第4期14卷 961-982页

作者： Qian-qing ZHANG Shan-Wei LIU ruo-Feng FENG Jian-Gu QIAN Chun-Yu CUI Geotechnical and Structural Engineering Research Center Shandong UniversityJinan 250061China Key Laboratory of Geotechrical and Underground Engineering of the Minstry of Education Tongji UniversityShanghai 200092China

A uniform arrangement of individual piles is commonly adopted in the conventional pile group foundation,and basin-shaped settlement is often observed in *** differential settlement of pile groups will decrease the use-safety requirements of building,even cause the whole-building tilt or *** reduce differential settlement among individual piles,non-uniformly arranged pile groups can be *** paper presents a finite element analysis on the response of pile groups with different layouts of individual piles in pile *** the userdefined subroutine FRIC as the secondary development platform,a softening model of skin friction and a hyperbolic model of end resistance are introduced into the contact pair calculation of ABAQUS *** to the response analysis of a single pile,the reliability of the proposed secondary development method of ABAQUS software is verified using an iterative computer *** reinforcing effects of individual piles is then analyzed using the present finite element ***,the response of non-uniformly arranged pile groups,e.g.,individual piles with variable length and individual piles with variable diameter,is analyzed using the proposed numerical analysis *** suggestions on the layout of individual piles are proposed to reduce differential settlement and make full use of the bearing capacity of individual piles in pile groups for practical purposes.

关键词： numerical simulation non-uniformly arranged pile groups differential settlement pile-soil interaction

An Edge-Based Anisotropic Mesh Refinement Algorithm and its Application to Interface Problems

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Communications in Computational Physics 2010年第8期8卷 511-540页

作者： Duan wang ruo Li Ningning Yan LMAM&School of Mathematical Sciences Peking University100871BeijingChina CAPT LMAM&School of Mathematical SciencesPeking University100871BeijingChina LSEC Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of Sciences100080BeijingChina

Based on an error estimate in terms of element edge vectors on arbitrary unstructured simplex meshes,we propose a new edge-based anisotropic mesh refinement *** the mesh adaptation indicator,the error estimate involves only the gradient of error rather than higher order *** preferred refinement edge is chosen to reduce the maximal term in the error *** algorithm is implemented in both two-and three-dimensional cases,and applied to the singular function interpolation and the elliptic interface *** numerical results demonstrate that the convergence order obtained by using the proposed anisotropic mesh refinement algorithm can be higher than that given by the isotropic one.

关键词： Adaptive finite element method anisotropic mesh refinement elliptic interface problem non-homogeneous jump a posteriori error estimate

Polymerizing Ladder-type Heteroheptacene-Cored Small-Molecule Acceptors for Efficient All-Polymer Solar Cells

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Chinese Journal of Polymer Science 2023年第7期41卷 1018-1026页

作者： Peng wang Yu-Hang Zhu Hong-Xin Tao Yun-Long Ma Dong-Dong Cai Qi-Sheng Tu ruo-Chuan Liao qing-Dong Zheng State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China School of Physical Science and Technology ShanghaiTech UniversityShanghai201210China State Key Laboratory of Coordination Chemistry College of Engineering and Applied SciencesNanjing UniversityNanjing210023China

One important subject in the field of all-polymer solar cells (all-PSCs) is the exploration of electron-deficient building blocks with optimized physicochemical properties to promote the performance of polymer acceptors. Here, two ladder-type heteroheptacene-containing small-molecule acceptors with branched 2-octyldodecyl or 2-hexyldecyl side-chains are synthesized and polymerized with the thiophene co-monomer to afford polymer acceptors (PW-OD and PW-HD) with strong near-infrared absorption. Experimental results reveal that the alkyl chain length has a large impact on the molecular packing behavior of the resulting polymers, which in turn affects their light-absorbing and charge transport properties, and thus the photovoltaic performance of the final devices. When blended with the polymer donor PM6, PW-HD-based all-PSCs deliver a higher power conversion efficiency (PCE) of 9.12% compared to the PCE of 6.47% for the PW-OD-based all-PSCs, mainly due to its more ordered inter-chain packing and more favorable blend morphology. This work provides a promising building block for the development of high-performance narrow-bandgap polymer acceptors and highlights the importance of side-chain substitution in optimizing the photovoltaic performance of polymer acceptors.

关键词： All-polymer solar cells Polymer acceptors Ladder-type heteroheptacene Power conversion efficiency

ARobust Riemann Solver for Multiple Hydro-Elastoplastic Solid Mediums

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Advances in Applied Mathematics and Mechanics 2020年第1期12卷 212-250页

作者： ruo Li Yanli wang Chengbao Yao HEDPS&CAPT LMAM&School of Mathematical SciencesPeking UniversityBeijingChina College of Engineering Peking UniversityBeijingChina School of Mathematical Sciences Peking UniversityBeijingChina and Northwest Institute of Nuclear TechnologyXi’anShaanxi 710024China

We propose a robust approximate solver for the hydro-elastoplastic solid material,a general constitutive law extensively applied in explosion and high speed impact dynamics,and provide a natural transformation between the fluid and solid in the case of phase *** hydrostatic components of the solid is described by a family of general Mie-Gruneisen equation of state(EOS),while the deviatoric component includes the elastic phase,linearly hardened plastic phase and fluid *** approximate solver provides the interface stress and normal velocity by an iterative *** well-posedness and convergence of our solver are proved with mild assumptions on the equations of *** proposed solver is applied in computing the numerical flux at the phase interface for our compressible multi-medium flow simulation on Eulerian *** numerical examples,including Riemann problems,shock-bubble interactions,implosions and high speed impact applications,are presented to validate the approximate solver.

关键词： Riemann solver Mie-Gruneisen hydro-elastoplastic solid multi-medium flow

Control Design for Transient Performance

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IEEE/CAA Journal of Automatica Sinica 2023年第1期10卷 3-7页

作者： qing-Guo wang Institute of Artificial Intelligence and Future Networks Beijing Normal University Guangdong Key Lab of AI and Multi-Modal Data Processing BNU-HKBU United International CollegeZhuhai 519087China

CONTROL systems are everywhere – chemical plants,energy systems, manufacturing, homes and buildings,automobiles and trains, medical devices, cellular telephones and internet, aircraft and spacecraft. Recent developments in these fields bring up the systems with the unprecedented scope, scale and complexity such as cyber-physical and human systems, and the required control task becomes more challenging than ever [1]。

关键词： telephone automobile everywhere

Numerical Regularized Moment Method for High Mach Number Flow

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Communications in Computational Physics 2012年第5期11卷 1415-1438页

作者： Zhenning Cai ruo Li Yanli wang School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China CAPT LMAM&School of Mathematical SciencesPeking UniversityBeijing 100871P.R.China

This paper is a continuation of our earlier work[SIAM ***.,32(2010),pp.2875-2907]in which a numericalmoment method with arbitrary order of moments was ***,the computation may break down during the calculation of the structure of a shock wave with Mach number M_(0)≥*** this paper,we concentrate on the regularization of the moment ***,we apply the Maxwell iteration to the infinite moment system and determine the magnitude of each moment with respect to the Knudsen *** that,we obtain the approximation of high order moments and close the moment systems by dropping some high-order *** is then performed to obtain a very simple regularization term,thus it is very convenient for numerical *** validate the new regularization,the shock structures of low order systems are computed with different shock Mach numbers.

关键词： Boltzmann-BGK equation Maxwellian iteration regularizedmoment equations

Two new prenylflavonoids from Morus nigra L.

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Chinese Chemical Letters 2009年第12期20卷 1469-1471页

作者： Lei wang Ting Gong ruo Yun Chen Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College The Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine Ministry of Education Beijing 100050 China

Two new prenylflavonoids, momigrol E（1） and mornigrol F（2） were isolated from Morus nigra L. Their structures were elucidated on the basis of spectroscopic methods, especially 2D-NMR techniques.

关键词： Morus nigra Moraceae Mornigrols E and F Prenylflavonoid

不同荷载作用下五边形石墨烯的变形破坏机理研究

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原子与分子物理学报 2025年第6期42卷 51-57页

作者：赵泽若韩同伟李仁葛峻铭王嘉越江苏大学土木工程与力学学院镇江212013

五边形石墨烯是一种完全由碳五元环组成的准二维的亚稳态碳结构,在不同载荷作用下其变形破坏机理仍需进一步研究.本文基于ReaxFF反应力场采用分子动力学方法模拟研究了五边形石墨烯的拉伸、剪切和纳米压痕破坏过程,得到了五边形石墨烯... 详细信息

五边形石墨烯是一种完全由碳五元环组成的准二维的亚稳态碳结构,在不同载荷作用下其变形破坏机理仍需进一步研究.本文基于ReaxFF反应力场采用分子动力学方法模拟研究了五边形石墨烯的拉伸、剪切和纳米压痕破坏过程,得到了五边形石墨烯的拉伸和剪切应力-应变曲线以及压入载荷-位移曲线,系统分析了五边形石墨烯的变形破坏机理,并验证了五边形石墨烯在不同载荷作用下是否表现出塑性变形特征的一致性问题.研究结果表明,通过拉伸或纳米压入等不同加载方式均可准确测出五边形石墨烯的本征力学性能参数,其杨氏模量265.4~285.1 N/m,与第一性原理计算结果一致.研究还发现,五边形石墨烯在拉伸、剪切和纳米压痕过程中均会出现不可逆的塑性变形特征,而引起塑性变形的原因是由于不可逆的碳五元环向碳多元环结构的转变.以上研究结果可为基于五边形石墨烯的微/纳米机电系统的实际应用提供重要指导.

关键词：五边形石墨烯变形破坏机理分子动力学

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Mixing and heat transfer of binary mixtures of monodispersed spherical particles with different densities and thermal diffusivities

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Particuology 2021年第5期19卷 118-130页

作者： qing wang Bowen Liu Engineering Research Centre of Oil Shale Comprehensive Utilization Ministry of EducationNortheast Electric Power UniversityJilin 132012China

Mixing and heat transfer among particles in rotating drums are widely applied in numerous industrial ***,mixing and heat transfer occur ***,the interrelationship between mixing and heat transfer must be investigated for industrial *** this study,the radial mixing and heat transfer of spherical granular materials(3 mm)with various properties in batch rotating drums are investigated numerically using the discrete element *** evolution of mixing and heat transfer characteristics with rotation speed is analyzed from the perspective of time and number of revolutions,*** results indicate that,depending on the physical parameters and thermal properties of particles,the mixing quality does not always accurately reflect the heat transfer *** binary granular beds of monodispersed spherical particles with different densities and thermal diffusivities,the main heat transfer mechanism is related to the ratio of the thermal conductivity of the particles to that of the fluid.

关键词： Rotating drums Discrete element method Mixing Heat conduction Heat radiation