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Bond-associated non-ordinary state-based peridynamic model for multiple spalling simulation of concrete

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Acta Mechanica Sinica 2021年第7期37卷 1104-1135,I0002页

作者： siyang yang Xin Gu Qing Zhang Xiaozhou Xia Department of Engineering Mechanics College of Mechanics and MaterialsHohai UniversityNanjing 211100China

The non-ordinary state-based peridynamic(NOSB PD)model has the capability of incorporating existing constitutive relationships in the classical continuum mechanics.In the present work,we first develop an NOSB PD model corresponding to the Johnson–Holmquist II(JH-2)constitutive damage model,which can describe the severe damage of concrete under intense impact compression.Besides,the numerical oscillation problem of the NOSB PD caused by zero-energy mode is analyzed and hence a bond-associated non-ordinary state-based peridynamic(BA-NOSB PD)model is adopted to remove the oscillation.Then,the elastic deformation of a three-dimensional bar is analyzed to verify the capability of BA-NOSB PD in eliminating the numerical oscillation.Furthermore,concrete spalling caused by the interaction of incident compression wave and reflected tension wave is simulated.The dynamic tensile fracture process of concrete multiple spalling is accurately reproduced for several examples according to the spalling number and spalling thickness analysis,illustrating the approach can well simulate and analyze the concrete spalling discontinuities.

关键词： Non-ordinary state-based peridynamics Bond-associated horizon-Johnson-HolmquistⅡ(JH-2)model Wave propagation Multiple spalling

Simulation of Inviscid Compressible Flows Using PDE Transform

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Communications in Computational Physics 2014年第10期16卷 1201-1238页

作者： Langhua Hu siyang yang Guo-Wei Wei Department of Mathematics Michigan State UniversityMI 48824USA. Department of Electrical and Computer Engineering Michigan State UniversityMI 48824USA. Center for Mathematical Molecular Biosciences Michigan State UniversityMI 48824USA.

The solution of systems of hyperbolic conservation laws remains an interesting and challenging task due to the diversity of physical origins and complexity of the physical situations.The present work introduces the use of the partial differential equation(PDE)transform,paired with the Fourier pseudospectral method(FPM),as a new approach for hyperbolic conservation law problems.The PDE transform,based on the scheme of adaptive high order evolution PDEs,has recently been applied to decompose signals,images,surfaces and data to various target functional mode functions such as trend,edge,texture,feature,trait,noise,etc.Like wavelet transform,the PDE transform has controllable time-frequency localization and perfect reconstruction.A fast PDE transform implemented by the fast Fourier Transform(FFT)is introduced to avoid stability constraint of integrating high order PDEs.The parameters of the PDE transform are adaptively computed to optimize the weighted total variation during the time integration of conservation law equations.A variety of standard benchmark problems of hyperbolic conservation laws is employed to systematically validate the performance of the present PDE transform based FPM.The impact of two PDE transform parameters,i.e.,the highest order and the propagation time,is carefully studied to deliver the best effect of suppressing Gibbs’oscillations.The PDE orders of 2-6 are used for hyperbolic conservation laws of low oscillatory solutions,while the PDE orders of 8-12 are often required for problems involving highly oscillatory solutions,such as shock-entropy wave interactions.The present results are compared with those in the literature.It is found that the present approach not only works well for problems that favor low order shock capturing schemes,but also exhibits superb behavior for problems that require the use of high order shock capturing methods.

关键词： Partial differential equation transform hyperbolic conservation laws Fourier pseudospectral method adaptive lowpass filters Gibbs’oscillations.

Kinetic-Thermodynamic Promotion Engineering toward High-Density Hierarchical and Zn-Doping Activity-Enhancing ZnNiO@CF for High-Capacity Desalination

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Nano-Micro Letters 2024年第8期16卷 35-50页

作者： Jie Ma siyang Xing Yabo Wang Jinhu yang Fei Yu College of Marine Ecology and Environment Shanghai Ocean University201306 ShanghaiPeople’s Republic of China School of Civil Engineering Kashi University844000 KashiPeople’s Republic of China Research Center for Environmental Functional Materials College of Environmental Science and EngineeringTongji University1239 Siping Road200092 ShanghaiPeople’s Republic of China School of Chemical Science and Engineering Tongji University1239 Siping Road200092 ShanghaiPeople’s Republic of China Department of Energy Environmental&Chemical EngineeringWashington University in St.LouisSt.LouisMO 63130USA

Despite the promising potential of transition metal oxides(TMOs)as capacitive deionization(CDI)electrodes,the actual capacity of TMOs electrodes for sodium storage is significantly lower than the theoretical capacity,posing a major obstacle.Herein,we prepared the kinetically favorable Zn_(x)Ni_(1−x)O electrode in situ growth on carbon felt(Zn_(x)Ni_(1−x)O@CF)through constraining the rate of OH^(−)generation in the hydrothermal method.Zn_(x)Ni_(1−x)O@CF exhibited a high-density hierarchical nanosheet structure with three-dimensional open pores,benefitting the ion transport/electron transfer.And tuning the moderate amount of redox-inert Zn-doping can enhance surface electroactive sites,actual activity of redox-active Ni species,and lower adsorption energy,promoting the adsorption kinetic and thermodynamic of the Zn_(0.2)Ni_(0.8)O@CF.Benefitting from the kinetic-thermodynamic facilitation mechanism,Zn_(0.2)Ni_(0.8)O@CF achieved ultrahigh desalination capacity(128.9 mgNaCl g^(-1)),ultra-low energy consumption(0.164 kW h kgNaCl^(-1)),high salt removal rate(1.21 mgNaCl g^(-1) min^(-1)),and good cyclability.The thermodynamic facilitation and Na^(+)intercalation mechanism of Zn_(0.2)Ni_(0.8)O@CF are identified by the density functional theory calculations and electrochemical quartz crystal microbalance with dissipation monitoring,respectively.This research provides new insights into controlling electrochemically favorable morphology and demonstrates that Zn-doping,which is redox-inert,is essential for enhancing the electrochemical performance of CDI electrodes.

关键词： Zinc-nickel metal oxide High-density hierarchical Capacitive deionization Zinc-doping

Detection Method for Cascading Failure of Power Systems Based on Epidemic Model

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1356-1370页

作者： Jian Xu Zhonghao He siyang Liao Yuanzhang Sun Liangzhong Yao Deping Ke Jun yang School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China IEEE

The early detection of cascading failure plays an important role in the safe and stable operation of the power system with high penetration of renewable energy.This paper proposes a fault propagation dynamic model based on the epidemic model,and further puts forward a method to detect the development of cascading failures.Through the simulation of the IEEE 39-bus and 118-bus systems,this model is proven to be valid and capable of providing practical technical support for the prevention of cascading failures in power systems with high penetration of renewable energy.This paper also provides an analysis method for the choice of different protection and control measures at each stage of cascading failure,which has critical significance and follow-up value.

关键词： Cascading failure complex network epidemic model fault propagation renewable energy weight method of game theory

Influence of pore structure on thermal stress distribution inside coal particles during primary fragmentation

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Particuology 2024年第2期85卷 49-61页

作者： Kai Qiao Shan Zhong siyang Tang Ke yang Hairong Yue Kui Ma Lei Song Bin Liang School of Chemical Engineering Sichuan UniversityChengdu610065China Institute of New Energy and Low-carbon Technology Chengdu610207China

Thermal stress is an important reason of coal particle primary fragmentation,during which the role of pore structure is ambiguous.Thermal stress induced fragmentation experiments were conducted with low volatile coal/char particles,and the results show that the fragmentation severity enhances with increasing porosity.Various porous thermal stress models were developed with finite element method,and the influences of the pore shape,size,position and porosity on the thermal stress were discussed.The maximum thermal stress inside particle increases with pore curvature,the pore position affects the thermal stress more significantly at the particle center and surface.The expectation of the maximum tensile thermal stress linearly increases with porosity,making the particles with higher porosity easier to fragment,contrary to the conclusion deduced from the devolatilization theory.The obtained results are valuable for the analysis of different thermal processes concerning the thermal stresses of the solid feedstocks.

关键词： Coal particle Primary fragmentation Thermal stress Pore structure Porosity

Multiplexed manipulation of orbital angular momentum and wavelength in metasurfaces based on arbitrary complex-amplitude control

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Light(Science & Applications) 2024年第5期13卷 930-940页

作者： Guoli He Yaqin Zheng Changda Zhou siyang Li Zhonghong Shi Yanhui Deng Zhang-Kai Zhou State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSun Yat-sen UniversityGuangzhou 510275China

Due to its unbounded and orthogonal modes,the orbital angular momentum(OAM)is regarded as a key optical degree of freedom(DoF)for future information processing with ultra-high capacity and speed.Although the manipulation of OAM based on metasurfaces has brought about great achievements in various fields,such manipulation currently remains at single-DoF level,which means the multiplexed manipulation of OAM with other optical DoFs is still lacking,greatly hampering the application of OAM beams and advancement of metasurfaces.In order to overcome this challenge,we propose the idea of multiplexed coherent pixel(MCP)for metasurfaces.This approach enables the manipulation of arbitrary complex-amplitude under incident lights of both plane and OAM waves,on the basis of which we have realized the multiplexed DoF control of OAM and wavelength.As a result,the MCP method expands the types of incident lights which can be simultaneously responded by metasurfaces,enriches the information processing capability of metasurfaces,and creates applications of information encryption and OAM demultiplexer.Our findings not only provide means for the design of high-security and high-capacity metasurfaces,but also raise the control and application level of OAM,offering great potential for multifunctional nanophotonic devices in the future.

关键词： momentum offering overcome

Characterization of Flame Retardancy and Oil-Water Separation Capacity of Superhydrophobic Silylated Melamine Sponges

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Fluid Dynamics & Materials Processing 2024年第2期20卷 383-400页

作者： Yongchun Liu Ni Qiao Yanli yang Yanchun Li Chunxiao He siyang Wang Chengcheng Liu Ruixia Lei Wang Li Wenwen Gao College of Chemistry and Chemical Engineering FLUOBON Pilot Base of Chemical EngineeringLongdong UniversityQingyang745000China Qingyang Solid and Hazardous Waste Pollution Prevention and Control Management Center Qingyang745000China Gansu Qingluyuan Environmental Monitoring Co. Ltd.Qingyang745000China School of Chemistry and Chemical Engineering Shanxi Key Laboratory of Low Metamorphic Coal Clean UtilizationYulin UniversityYulin719000China

A silylated melamine sponge(SMS)was prepared by two simple steps,namely,immersion and dehydration of a melamine sponge coated with methyltrichlorosilane.The silylated structure of SMS was characterized by FT-IR(Fourier-transform infrared)spectroscopy,SEM(Scanning electron microscopy)and in terms of water contact angles.Its oil-water absorption and separation capacities were measured by FT-IR and UV-visible spectrophoto-metry.The experimental results have shown that oligomeric silanol covalently bonds by Si-N onto the surface of melamine sponge skeletons.SMS has shown superhydrophobicity with a water contact angle exceeding 150°±1°,a better separation efﬁciency with regard to diesel oil(by 99.31%(wt/wt%)in oil-water mixture and even up to 99.99%(wt/wt%)for diesel oil in its saturated aqueous solution.Moreover,SMS inherited the intrinsicﬂame retardancy of the melamine sponge.In general,SMS has shown superhydrophobicity,high porosity,excellent selectivity,remarkable recyclability,and better absorption capacity for various oils and organic solvents,and a high separation efﬁciency for oil in saturated aqueous solutions.

关键词： Methyltrichlorosilane silylated melamine sponge(SMS) superhydrophobicity absorption capacity oil-water separable efﬁciency ﬂame retardancy

Light-triggered fluorochromic cholesteric liquid crystal elastomer with hydrogen-bonded fluorescent switch: dualmodal-switchable circularly polarized luminescence

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Science China Chemistry 2024年第8期67卷 2719-2727页

作者： siyang Lin Tianqi Ren Xianyu Meng Wenxin Kang Jinbao Guo Key Laboratory of Carbon Fibers and Functional Polymers Ministry of Education College of Materials Science and Engineering Beijing University of Chemical Technology

Solid materials with dynamically tunable circularly polarized luminescence（CPL） feature higher security levels and devicefriendly characteristics, showing great superiority in the field of information technology and anti-counterfeiting. To address the limited photoisomerization of fluorescent photoswitch in CPL-active solid materials, here a cholesteric liquid crystal elastomer（CLCE） containing a hydrogen-bonded（H-bonded） polymerizable fluorescent switch AHBA-PSD is prepared. Owing to the good flexibility and low glass-transition temperature of CLCE, AHBA-PSD shows a fast and fully reversible photocyclization/cycloreversion with fluorochromic behavior in CLCE. Further, by controlling the spectral overlapping area between the emission and reflection bands, the CLCE exhibits a strong CPL with a glumvalue of up to 0.76 accompanied by a reversible phototunable CPL signal. Meanwhile, the H-bond helps to stabilize the mechanical property, and the force-induced switching-off of CPL signal could be achieved due to the destroyed helical structures by external force. Finally, an automatically-recognized identification card with abundant chiroptical information is demonstrated.

关键词： cholesteric liquid crystal elastomer circularly polarized luminescence diarylethene fluorescent photoswitch photoismerization

Imide-based covalent organic framework with excellent cyclability as an anode material for lithium-ion battery

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Chinese Chemical Letters 2024年第6期35卷 206-210页

作者： Yue Qian Zhoujia Liu Haixin Song Ruize Yin Hanni yang siyang Li Weiwei Xiong Saisai Yuan Junhao Zhang Huan Pang School of Environmental&Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Chemistry&Chemical Engineering Yangzhou UniversityYangzhou 225009China Shandong Key Laboratory of Biochemical Analysis College of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China

Covalent organic frameworks(COFs)exhibiting reversible redox behaviors have been identified as promising candidates for constructing electrode materials in lithium-ion batteries(LIBs).However,their extensive application has been limited due to finite redox sites and poor structural stability.In this study,we design and synthesize a novel polyimide covalent organic framework(PI-COF)using the traditional solvothermal method and successfully apply it as an anode material for LIBs.The large conjugated structure of PI-COF accelerates charge transfer,while its large surface area provides more active sites,making PI-COF an attractive anode material for LIBs.Furthermore,the PI-COF anode material demonstrates high reversible specific capacity and excellent long-term cycling stability due to its COF characteristics.Specifically,the PI-COF electrodes deliver a specific capacity of 800 m Ah/g at a current density of 200 m A/g after 200 cycles,while a specific capacity of 450 m Ah/g at a current density of 1000 m A/g is sustained after 800 cycles.The outstanding lithium storage capacity,particularly the satisfactory long-term cycling stability,establishes PI-COF as a promising material for LIBs.

关键词： Ethylenediaminetetraacetic dianhydride Covalent organic frameworks Polyimide Lithium-ion battery Anode material