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Effect of Texture on the Grain-Size-Dependent Functional Properties of NiTi Shape memory Alloys and Texture Gradient Design:A Phase Field Study

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Acta mechanica Solida Sinica 2024年第1期37卷 10-32页

作者： Bo Xu Beihai Huang Chong wang Qingyuan wang Failure mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan ProvinceSichuan UniversityChengdu 610065China Department of mechanical Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China Key Laboratory of Deep Underground Science and Engineering Ministry of EducationSichuan UniversityChengdu 610065China

Texture is inevitably introduced during the manufacturing of most NiTi shape memory alloys(SmAs),and the textured nanocrystalline NiTi has been extensively employed in ***,the effect of texture,and the joint effect of grain size(GS)and texture on the functional properties of NiTi SmAs and the corresponding microscopic mechanisms have not been clearly understood *** this work,based on the phase field method,the effect of texture on the GS-dependent functional properties of NiTi SmAs,including super-elasticity(SE),one-way shape memory effect(OWSmE),and stress-assisted two-way shape memory effect(SATWSmE),is investigated,and the corresponding microscopic mechanisms are ***,the samples with discrete geometrical gradients and/or texture gradients are designed to achieve graded functional *** simulation results indicate that the dependence of functional properties on texture is due to the effect of crystallographic orientation on martensite transformation and reorientation,which can lead to different inelastic *** the designed samples with texture gradients,the stress–strain responses of sheets with various textures are different,allowing for the coordination of overall deformation of the sample by combining such sheets,with varying inelastic deformation ***,the overall response of the sample differs from that without texture gradient,leading to the achievement of graded functional *** simulation results and new findings in this work contribute to a deeper understanding of the effects of texture,GS,and their interaction on the functional properties of SmAs,and provide valuable reference for the design and development of SmA-based devices with desired functional properties.

关键词： Phase field NiTi shape memory alloy Texture Grain size Functional property Texture gradient

Dynamics modeling and optimal control for multi-information diffusion in Social Internet of Things

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Digital Communications and Networks 2024年第3期10卷 655-665页

作者： yaguang Lin Xiaoming wang Liang wang Pengfei Wan School of Computer Science Shaanxi Normal UniversityXi'an710119China

As an ingenious convergence between the Internet of Things and social networks,the Social Internet of Things(SIoT)can provide effective and intelligent information services and has become one of the main platforms for people to spread and share ***,SIoT is characterized by high openness and autonomy,multiple kinds of information can spread rapidly,freely and cooperatively in SIoT,which makes it challenging to accurately reveal the characteristics of the information diffusion process and effectively control its *** this end,with the aim of exploring multi-information cooperative diffusion processes in SIoT,we first develop a dynamics model for multi-information cooperative diffusion based on the system dynamics theory in this ***,the characteristics and laws of the dynamical evolution process of multi-information cooperative diffusion are theoretically investigated,and the diffusion trend is *** this basis,to further control the multi-information cooperative diffusion process efficiently,we propose two control strategies for information diffusion with control objectives,develop an optimal control system for the multi-information cooperative diffusion process,and propose the corresponding optimal control *** optimal solution distribution of the control strategy satisfying the control system constraints and the control budget constraints is solved using the optimal control ***,extensive simulation experiments based on real dataset from Twitter validate the correctness and effectiveness of the proposed model,strategy and method.

关键词： Social Internet of Things Information diffusion Dynamics modeling Trend prediction Optimal control

Dynamic performance and parameter optimization of a half-vehicle system coupled with an inerter-based X-structure nonlinear energy sink

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Applied mathematics and mechanics(English Edition) 2024年第1期45卷 85-110页

作者： yong wang Peili wang Haodong mENG Liqun CHEN .Automotive Engineering Research Institute Jiangsu UniversityZhenjiang 212013Jiangsu ProvinceChina Guangxi Key Laboratory of Automobile Components and Vehicle Technology Guangxi University of Science and TechnologyLiuzhou 545006Guangxi Zhuang Autonomous RegionChina School of Automotive Engineering Changzhou Institute of TechnologyChangzhou 213032Jiangsu ProvinceChina Shanghai Key Laboratory of mechanics in Energy Engineering Shanghai Frontier Science Center of MechanoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China

Inspired by the demand of improving the riding comfort and meeting the lightweight design of the vehicle, an inerter-based X-structure nonlinear energy sink(IXNES) is proposed and applied in the half-vehicle system to enhance the dynamic performance. The X-structure is used as a mechanism to realize the nonlinear stiffness characteristic of the NES, which can realize the flexibility, adjustability, high efficiency, and easy operation of nonlinear stiffness, and is convenient to apply in the vehicle suspension, and the inerter is applied to replacing the mass of the NES based on the mass amplification characteristic. The dynamic model of the half-vehicle system coupled with the IX-NES is established with the Lagrange theory, and the harmonic balance method(HBm) and the pseudo-arc-length method(PALm) are used to obtain the dynamic response under road harmonic excitation. The corresponding dynamic performance under road harmonic and random excitation is evaluated by six performance indices, and compared with that of the original half-vehicle system to show the benefits of the IX-NES. Furthermore, the structural parameters of the IX-NES are optimized with the genetic algorithm. The results show that for road harmonic and random excitation, using the IX-NES can greatly reduce the resonance peaks and root mean square(RmS) values of the front and rear suspension deflections and the front and rear dynamic tire loads, while the resonance peaks and RmS values of the vehicle body vertical and pitching accelerations are slightly *** the structural parameters of the IX-NES are optimized, the vehicle body vertical and pitching accelerations of the half-vehicle system could reduce by 2.41% and 1.16%,respectively, and the other dynamic performance indices are within the reasonable ***, the IX-NES combines the advantages of the inerter, X-structure, and NES, which improves the dynamic performance of the half-vehicle system and provides an effective option for vibrati

关键词： inerter X-structure nonlinear energy sink(NES) half-vehicle system dynamic performance

Boson star superradiance

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Science China(Physics,mechanics & Astronomy) 2024年第6期67卷 69-78页

作者： He-yu Gao Paul m.Saffin yi-Jie wang Qi-Xin Xie Shuang-yong Zhou School of Physical Sciences University of Science and Technology of ChinaHefei 230026China School of Physics and Astronomy University of NottinghamUniversity ParkNottingham NG72RDUK Interdisciplinary Center for Theoretical Study University of Science and Technology of ChinaHefei 230026China Peng Huanwu Center for Fundamental Theory Hefei 230026China

Recently,it has been realized that in some systems internal space rotation can induce energy amplification for scattered waves,similar to rotation in real *** particularly,it has been shown that energy extraction is possible for a Q-ball,a stationary non-topological soliton that is coherently rotating in its field *** this paper,we generalize the analysis to the case of boson stars,and show that the same energy extraction mechanism still works for boson stars.

关键词： superradiance boson star field space rotation

Nano-enhanced solid-state hydrogen storage:Balancing discovery and pragmatism for future energy solutions

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Nano Research 2024年第10期17卷 8729-8753页

作者： Chaochao Dun Xinyi wang Linfeng Chen Sichi Li Hanna m.Breunig Jeffrey J.Urban The molecular Foundry Lawrence Berkeley National Laboratory BerkeleyBerkeleyCA 94720USA Energy Analysis and Environmental Impacts Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA Lawrence Livermore National Laboratory LivermoreCA 94550USA

Nanomaterials have revolutionized the battery industry by enhancing energy storage capacities and charging speeds,and their application in hydrogen(H_(2))storage likewise holds strong potential,though with distinct challenges and mechanisms.H_(2) is a crucial future zero-carbon energy vector given its high gravimetric energy density,which far exceeds that of liquid ***,its low volumetric energy density in gaseous form currently requires storage under high pressure or at low *** review critically examines the current and prospective landscapes of solid-state H_(2) storage technologies,with a focus on pragmatic integration of advanced materials such as metal-organic frameworks(mOFs),magnesium-based hybrids,and novel sorbents into future energy *** materials,enhanced by nanotechnology,could significantly improve the efficiency and capacity of H_(2) storage systems by optimizing H_(2) adsorption at the nanoscale and improving the kinetics of H_(2) uptake and *** discuss various H_(2) storage mechanisms—physisorption,chemisorption,and the Kubas interaction—analyzing their impact on the energy efficiency and scalability of storage *** review also addresses the potential of“smart mOFs”,single-atom catalyst-doped metal hydrides,mXenes and entropy-driven alloys to enhance the performance and broaden the application range of H_(2) storage systems,stressing the need for innovative materials and system integration to satisfy future energy ***-throughput screening,combined with machine learning algorithms,is noted as a promising approach to identify patterns and predict the behavior of novel materials under various conditions,significantly reducing the time and cost associated with experimental *** closing,we discuss the increasing involvement of various companies in solid-state H_(2) storage,particularly in prototype vehicles,from a techno-economic *** forward-looking perspective underscores t

关键词： nanomaterials nanotechnology solid-state H_(2)storage techno-economic analysis model-driven material development processes

Continuous-wave operation of 1550 nm low-threshold triple-lattice photonic-crystal surface-emitting lasers

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Light(Science & Applications) 2024年第3期13卷 446-453页

作者： Ziye wang Xia Liu Pinyao wang Huanyu Lu Bo meng Wei Zhang Lijie wang yanjing wang Cunzhu Tong State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Center of materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Central Research Institute Planning Dept 2012 LabsHuawei Technologies Company Ltd.Shenzhen 518129China

Benefitting from narrow beam divergence,photonic crystal surface-emitting lasers are expected to play an essential role in the ever-growing fields of optical communication and light detection and *** operating with 1.55μm wavelengths have attracted particular attention due to their minimum fiber loss and high eye-safe ***,high interband absorption significantly decreases their performance at this 1.55μm ***,stronger optical feedback is needed to reduce their threshold and thus improve the output *** this goal,photonic-crystal resonators with deep holes and high dielectric contrast are often ***,the relevant techniques for high-contrast photonic crystals inevitably complicate fabrication and reduce the final *** this paper,we demonstrate the first continuous-wave operation of 1.55μm photonic-crystal surface-emitting lasers by using a‘triple-lattice photonic-crystal resonator’,which superimposes three lattice point groups to increase the strength of in-plane optical *** this geometry,the in-plane 180°coupling can be enhanced threefold compared to the normal single-lattice *** theoretical and experimental investigations demonstrate the much lower threshold current density of this structure compared to‘single-lattice’and‘double-lattice’photonic-crystal resonators,verifying our design *** findings provide a new strategy for photonic crystal laser miniaturization,which is crucial for realizing their use in future high-speed applications.

关键词： resonator crystal lattice

On Existence of the Even L_(p)Gaussian minkowski Problem for p>n

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Chinese Annals of mathematics,Series B 2024年第2期45卷 179-192页

作者： Hejun wang School of mathematics and Statistics Shandong Normal UniversityJi'nan 250014China

This paper concerns the even L_(p)Gaussian minkowski problem in n-dimensional Euclidean space R^(n).The existence of the solution to the even L_(p)Guassian minkowski problem for p>n is obtained.

关键词： Convex body Existence L_(p)Gaussian surface area measure The even L_(p)Gaussian minkowski problem

Numerical three-dimensional modeling of earthen dam piping failure

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Water Science and Engineering 2024年第1期17卷 72-82页

作者： Zhengang wang Independent Researcher HerndonVA 20171USA

A physically-based numerical three-dimensional earthen dam piping failure model is developed for homogeneous and zoned soil *** model is an erosion model,coupled with force/moment equilibrium *** flow and two-dimensional(2D)shallow water equations(SWE)are solved to simulate dam break flows at different breaching *** rates of different soils with different construction compaction efforts are calculated using corresponding erosion *** dam's real shape,soil properties,and surrounding area are *** outer 2D-SWE grids are used to control upstream and downstream hydraulic conditions and control the boundary conditions of orifice flow,and inner 2D-SWE flow is used to scour soil and perform force/moment equilibrium *** model is validated using the European Commission ImPACT(Investigation of Extreme Flood Processes and Uncertainty)Test#5 in Norway,Teton Dam failure in Idaho,USA,and Quail Creek Dike failure in Utah,*** calculated peak outflows are within 10%errors of observed *** results show that,for a V-shaped dam like Teton Dam,a piping breach location at the abutment tends to result in a smaller peak breach outflow than the piping breach location at the dam's center;and if Teton Dam had broken from its center for internal erosion,a peak outflow of 117851 m'/s,which is 81%larger than the peak outflow of 65120 m3/s released from its right abutment,would have been released from Teton Dam.A lower piping inlet elevation tends to cause a faster/earlier piping breach than a higher piping inlet elevation.

关键词： 3D dam breach model 2D shallow water equations 3D slope stability analysis Piping failure Teton Dam Quail Creek Dike

Discovery and characterization of naturally occurring covalent inhibitors of SARS-CoV-2 m^(pro)from the antiviral herb Ephedra

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Chinese Journal of Natural medicines 2024年第9期22卷 797-807页

作者： HU Qing ZHANG yiwen CHEN Pengcheng ZHANG yani ZHU Guanghao LIU Wei wang Chaoran ZHENG Shuilian SHEN Nonger wang Haonan HUANG Ping GE Guangbo Center for Clinical Pharmacy Cancer CenterDepartment of PharmacyZhejiang Provincial People’s Hospital(Affiliated People’s Hospital)Hangzhou Medical CollegeHangzhou 310014China Shanghai Frontiers Science Center of TCm Chemical Biology Institute of Interdisciplinary Integrative Medicine ResearchShanghai University of Traditional Chinese MedicineShanghai 201203China Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese medicine Shanghai 200021China Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023China

The Chinese herb Ephedra(also known as mahuang)has been extensively utilized for the prevention and treatment of coronavirus-induced diseases,including coronavirus disease 2019(COVID-19).However,the specific anti-SARS-CoV-2 compounds and mechanisms have not been fully *** main protease(m^(pro))of SARS-CoV-2 is a highly conserved enzyme responsible for proteolytic processing during the viral life cycle,making it a critical target for the development of antiviral *** study aimed to identify naturally occurring covalent inhibitors of SARS-CoV-2 m^(pro)from Ephedra and to investigate their covalent binding *** results demonstrated that the non-alkaloid fraction of Ephedra(ENA)exhibited a potent inhibitory effect against the SARS-CoV-2 m^(pro)effect,whereas the alkaloid fraction did ***,the chemical constituents in ENA were identified,and the major constituents'anti-SARS-CoV-2 m^(pro)effects were *** the tested constituents,herbacetin(HE)and gallic acid(GA)were found to inhibit SARS-CoV-2 m^(pro)in a time-and dose-dependent *** combination displayed a significant synergistic effect on this key ***,various techniques,including inhibition kinetic assays,chemoproteomic methods,and molecular dynamics simulations,were employed to further elucidate the synergistic anti-m^(pro)mechanisms of the combination of HE and ***,this study deciphers the naturally occurring covalent inhibitors of SARS-CoV-2 m^(pro)from Ephedra and characterizes their synergistic anti-m^(pro)synergistic effect,providing robust evidence to support the anti-coronavirus efficacy of Ephedra.

关键词： main protease Ephedra Ephedra non-alkaloid fraction Covalent inhibitors Synergistic effect