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Advances in Applied Mathematics and Mechanics 2019年第1期11卷 108-131页

作者： yongxing hong Jun Lu Ji Lin Wen Chen State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering International Center for Simulation Software in Engineering and SciencesCollege of Mechanics and MaterialsHohai UniversityNanjing 211100China Nanjing Hydraulic Research Institute Hujuguan 34 RoadNanjing 210024China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing 210098China

The aim of this paper is to propose a fast meshless numerical scheme for the simulation of non-linear Schrodinger *** the proposed scheme,the implicit-Euler scheme is used for the temporal discretization and the localized method of approximate particular solution(LMAPS)is utilized for the spatial *** multiple-scale technique is introduced to obtain the shape parameters of the multiquadric radial basis function for 2D problems and the Gaussian radial basis function for 3D *** numerical examples are carried out to verify the accuracy and efficiency of the proposed *** with well-known techniques,numerical results illustrate that the proposed scheme is of merits being easy-to-program,high accuracy,and rapid convergence even for long-term *** results also indicate that the proposed scheme has great potential in large scale problems and real-world applications.

关键词： Schrodinger equation Localized method of approximate particular solution Shape parameters Multiple-scale technique

New method for the determination of convective heat transfer coefficient in fully-developed laminar pipe flow

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Acta Mechanica Sinica 2022年第1期38卷 100-109页

作者： Ji Lin yongxing hong Jun Lu Key Laboratory of Ministry of Education for Coastal Disaster and Protection Hohai UniversityNanjing 210098China College of Mechanics and Materials Hohai UniversityNanjing 211100China Nanjing Hydraulic Research Institute Hujuguan 34 RoadNanjing 210024China

Convective heat transfer coefficient is one of the most vital parameters which reveals the thermal efficiency of a pipe *** obtain such coefficients for problems with variable pipe wall temperature,numerical iterative methods should be used which could be time-consuming and less *** this paper,thermophysical properties of fluids are assumed to be *** define a variable related to the temperature gradient of the pipe wall and study the varying law of the local ***,a sample-based scheme is proposed to avoid the calculation of a time-consuming problem in the use of solutions with low computing *** verify its accuracy,several problems in normal circle pipes with variable factors,such as the various temperatures of the pipe wall,the different radius of the pipe,and various velocities of fluid flow,are well ***,its validity in a convergent pipe is also *** the obtained results,the high accuracy and efficiency of the proposed scheme can be ***,the proposed scheme for determining the convective heat transfer coefficient has great potential in engineering problems.

关键词： Convective heat transfer Laminar flow Pipe wall temperature parameter Similarity analysis

An Asynchronous Variational Integrator for Contact Problems Involving Elastoplastic Solids

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Acta Mechanica Solida Sinica 2024年第2期37卷 305-315页

作者： Zongwu Niu Zixiao Wang yongxing Shen University of Michigan-Shanghai Jiao Tong University Joint Institute Shanghai Jiao Tong UniversityShanghai200240China School of Agriculture and Biology Shanghai Jiao Tong UniversityShanghai200240China Department of Biostatistics Johns Hopkins Bloomberg School of Public HealthBaltimoreMaryland21205USA

Simulations of contact problems involving at least one plastic solid may be costly due to their strong nonlinearity and requirements of *** this work,we develop an explicit asynchronous variational integrator(AVI)for inelastic non-frictional contact problems involving a plastic *** AVI assigns each element in the mesh an independent time step and updates the solution at the elements and nodes *** asynchrony makes the AVI highly efficient in solving such bi-material *** advantage of the AVI,the constitutive update is locally performed in one element at a time,and contact constraints are also enforced on only one *** time step of the contact element is subdivided into multiple segments,and the fields are updated *** a contact event,only one element involving a few degrees of freedom is considered,leading to high *** proposed formulation is first verified with a pure elastodynamics benchmark and further applied to a contact problem involving an elastoplastic solid with non-associative volumetric *** numerical results indicate that the AVI exhibits excellent energy behaviors and has high computational efficiency.

关键词： Asynchronous variational integrator Plasticity Contact Computational efficiency Finite element method

Recent progress in the research on magnesium and magnesium alloy foils:A short review

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 842-854页

作者： Qiuyan Shen yongxing Ba Peng Zhang Jiangfeng Song Bin Jiang Fusheng Pan National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China National Key Laboratory of Advanced Casting Technologies Chongqing UniversityChongqing 400044China

Magnesium and magnesium alloy foils have great potential for application in battery anodes,electromagnetic shielding,optics and acoustics,and biology because of their excellent specific damping,internal dissipation coefficients,magnetic and electrical conductivities,as well as high theoretical specific ***,magnesium alloys exhibit poor deformation ability due to their hexagonal close-packed crystal *** magnesium and magnesium alloy foils with thicknesses of less than 0.1 mm is difficult because of surface oxidation and grain growth at high temperatures or severe anisotropy after cold rolling that leads to *** methods have been applied to prepare magnesium alloy *** include warm rolling,cold rolling,accumulative roll bonding,electric plastic rolling,and on-line heating *** of magnesium and magnesium alloy foils during preparation,such as edge cracks and breakage,are important factors for ***,the current status of the research on magnesium and magnesium alloy foils is summarized from the aspects of foil preparation,defect control,performance characterization,and application *** advantages and disadvantages of different preparation methods and defect(edge cracks and breakage)mechanisms in the preparation of foils are identified.

关键词： magnesium alloy foil rolling defect performance application

Ultra-efficient and parameter-free computation of submicron thermal transport with phonon Boltzmann transport equation

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Fundamental Research 2024年第4期4卷 907-915页

作者： Yue Hu yongxing Shen Hua Bao University of Michigan-Shanghai Jiao Tong University Joint Institute Shanghai Jiao Tong UniversityShanghai 200240China

Understanding thermal transport at the submicron scale is crucial for engineering applications,especially in the thermal management of electronics and tailoring the thermal conductivity of thermoelectric *** the submicron scale,the macroscopic heat diffusion equation is no longer valid and the phonon Boltzmann transport equation(BTE)becomes the governing equation for thermal ***,previous thermal simulations based on the phonon BTE have two main limitations:relying on empirical parameters and prohibitive computational ***,the phonon BTE is commonly used for qualitatively studying the non-Fourier thermal transport phenomena of toy *** this work,we demonstrate an ultra-efficient and parameter-free computational method of the phonon BTE to achieve quantitatively accurate thermal simulation for realistic materials and *** properly integrating the phonon properties from first-principles calculations,our method does not rely on empirical material properties *** can be generally applicable for different materials and the predicted results can match well with experimental ***,by developing a suitable ensemble of advanced numerical algorithms,our method exhibits superior numerical *** full-scale(from ballistic to diffusive)thermal simulation of a 3-dimensional fin field-effect transistor with 13 million degrees of freedom,which is prohibitive for existing phonon BTE solvers even on supercomputers,can now be completed within two hours on a single personal *** method makes it possible to achieve the predictive design of realistic nanostructures for the desired thermal *** also enables accurately resolving the temperature profiles at the transistor level,which helps in better understanding the self-heating effect of electronics.

关键词： Submicron thermal transport Boltzmann transport equation Deterministic numerical method Phonon transport Transistors Nanostructured materials

A supramolecular self-assembly material based on cucurbituril and cationic TPE as ultra-sensitive probe of energetic pentazolate salts

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Defence Technology（防务技术） 2024年第5期35卷 69-76页

作者： Boan Tang Jingxiang Zhong Shutao Wang Shiyu Zhou yongxing Tang Wei Huang School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China

The successful synthesis of the pentazolate anion(cyclo-N-5)has been a great breakthrough in the field of energetic ***,the detection methods for these energetic materials based on the pentazolate anion are quite ***,two fluorescent probes for cyclo-N-5anion were *** 1(TPE2N)was synthesized with a tetraphenylethylene functionalized by two cationic groups which can generate strong electrostatic interactions with pentazolate anion and result in specific fluorescent *** 2 was designed based on sensor 1 and supramolecular cucurbit[7]uril(CB[7]).The unique structural features of CB[7]provide sites for the interaction between the cations and N-5anion in its cavity,which would generate a platform for the detection and enhance the recognition *** titration calorimetry(ITC)experiment and fluorescence titration experiment indicate the binding molar ratio between sensor 1 with CB[7]is 1:*** sensors display typical aggregation-induced emission(AIE)features and good *** sensors demonstrate excellent sensitivity to pentazole hydrazine salt with high enhancement constant(sensor 1:1.34×10^(6);sensor 2:3.78×10^(6))and low limit of detection(LOD:sensor 1=4.33μM;sensor 2=1.54μM).The formation of an AIE-based supramolecular sensor effectively improves the sensitivity to *** addition,the probes also have good selectivity of N-5anion *** research would shed some light on the design of novel fluorescent sensors to detect pentazolate-based molecules and provides an example of supramolecular chemistry combined with fluorescent probes.

关键词： Pentazolate anion Explosives detection Aggregation-induced emission(AIE) Host-guest interaction

One-step hydrothermal synthesis of few-layered metallic phase MoS2 for high-performance supercapacitors

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Progress in Natural Science:Materials International 2024年第2期34卷 429-436页

作者： Jing Xu Xulong Yuan Yujie Zhao Shaoqi Rui Qingling Jia Han Li Shun Lu Bing Li yongxing Zhang Xuebin Zhu Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation Anhui Province Key Laboratory of Intelligent Computing and Applications Anhui Province Industrial Generic Technology Research Center for Alumics Materials Huaibei Normal University Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences Key Laboratory of Materials Physics Institute of Solid State Physics HFIPS Chinese Academy of Sciences

In recent years,molybdenum disulfide（MoS2） has gained significant attention in the scientific *** MoS2demonstrates unique properties and potential ***,the synthesis of few-layered and high-purity 1T-MoS2is still a *** this study,we successfully employed a hydrothermal method to synthesize few-layered and high-purity *** purity of the material is controlled by a combination of sodium borohydride and ***,the few-layered 1T-MoS2exhibits exceptional performance as a supercapacitor,including the high specific capacitance(250.3 F g-1at a current density of 1 A g-1) and excellent long-trem cycling stability（90.7 % after 5000 cycles）.Meanwhile,the asymmetric device assembled by 6-FL-1TMoS2and active carbon on carbon cloths exhibits excellent flexibility and high energy and power density(23.1μWh cm-2at 600 μW cm-2,55 μWh cm-2at 12000 μW cm-2).This work provides valuable insights into the synthesis of few-layered and high-purity 1T-MoS2,opening up new avenues for further research and applications.

关键词： 1T-MoS2 Few-layered High-purity One-pot hydrothermal method Supercapacitor

Focus control of wide-angle metalens based on digitally encoded metasurface

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Opto-Electronic Advances 2024年第8期7卷 26-41页

作者： Yi Chen Simeng Zhang Ying Tian Chenxia Li Wenlong Huang Yixin Liu yongxing Jin Bo Fang Zhi hong Xufeng Jing Institute of Optoelectronic Technology China Jiliang UniversityHangzhou 310018China Centre for THz Research China Jiliang UniversityHangzhou 310018China College of Metrology&Measurement Engineering China Jiliang UniversityHangzhou 310018China College of Information Engineering China Jiliang UniversityHangzhou 310018China

Based on the principle of super-symmetric lens with quadratic phase gradient transformation, combined with the principle of digital coding of metasurface, we propose a wide-angle coded metalens for focusing control in two-dimensional space. This metalens achieves focus shift in the x-direction by changing the oblique incidence angle of the incident wave,and focus control in the y-direction by combining with the convolution principle of the digitally coded metasurface to achieve flexible control of light focusing in the two-dimensional plane. The metasurface unit is mainly composed of threelayer of metal structure and two layers of medium, and the transmission phase is obtained by changing the middle layer of metal structure, which in turn obtains the required phase distribution of the metalens. The design of the metalens realizes the function of the lens with a large viewing angle at the x-polarized incidence, and realizes two-dimensional focus control. Experimentally, we prepared the designed coding metalens and tested the focus control function of the wide-angle coding metalens. The experimental results are in good agreement with the design results.

关键词： metasurface metalens wide-angle coding

Research progresses of nanomaterials as lubricant additives

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Friction 2024年第7期12卷 1347-1391页

作者： Zhengquan JIANG Yankun SUN Bokang LIU Laigui YU Yuping TONG Mingming YAN Zhongzheng YANG yongxing HAO Linjian SHANGGUAN Shengmao ZHANG Weihua LI School of Materials Science and Engineering North China University of Water Resources and Electric PowerZhengzhou 450045China Institute of Special Friction and Lubricating Materials North China University of Water Resources and Electric PowerZhengzhou 450045China Nanomaterials Engineering Research Center Henan UniversityKaifeng 475001China School of Mechanical Engineering North China University of Water Resources and Electric PowerZhengzhou 450045China

Friction and wear are unavoidable in mechanical *** use of lubricants with nano-additives can effectively reduce friction and wear,which is of great significance to saving energy and protecting the *** present,great progress has been made in the scientific research and industrial application of nano-additives for *** paper mainly introduces the types of nano-additives for lubricants(such as carbon nanomaterials,nano-metals,nano-oxides,sulfides,complexes,polymers,etc.),the tribological properties of lubricants with different components of nano-additives,and the lubrication mechanisms of the nano-additives(including tribofilm formation,rolling ball bearing effect,repairing effect,polishing effect,and synergistic effect).It also deals with the dispersion of nano-additives in lubricants and the influences of their particle size and microstructure on the tribological properties of *** review outlines the performance requirements of nano-additives in different lubrication states,discusses the use of nano-additives in challenging working conditions,and identifies various industrial oil nano-additives with reference to the appropriate options in diverse working ***,the existing problems of nano-additives and their application prospects are *** review,hopefully,would help to shed light on the design and synthesis of novel high-performance nano-additives and promote their application in engineering.

关键词： nanomaterials lubricant additive lubrication mechanism research progress

Acousto-optic scanning multi-photon lithography with high printing rate

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Opto-Electronic Advances 2024年第2期7卷 1-3页

作者： Minghui hong Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005China

As a manufacturing method that is focused on end-users,3D printing has gained a lot of attention in recent years due to its unique advantages in fabricating complex three-dimensional *** new micro-nano 3D printing methods have been developed to meet the demand for high-precision and high-yield *** them,multi-photon-photon lithography(MPL) is a promising 3D nanofabrication technology due to its capability of true 3D digital processing and nanoscale processing resolution beyond the diffraction *** has been widely used to fabricate microoptics10,11,photonic crystals12,microfluidics13,meta-surfaces14,and mechanical metamaterials15.

关键词： photon Acous scanning