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Second-Harmonic Generation of a Plane Wave Normally Incident upon a Solid Plate Immersed in Liquid

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Chinese Physics Letters 2013年第12期30卷 58-61页

作者： DENG Ming-Xi XIANG Yan-Xun WANG Ping LV Xia-Fu department of Physics Logistics Engineering UniversityChongqing 401331 School of mechanical and Power engineering East China University of Science and TechnologyShanghai 200237 department of Automation Chongqing University of Posts and TelecommunicationsChongqing 400065

We theoretically investigate the second-harmonic generation of a plane longitudinal wave normally incident upon a solid plate immersed in *** formulation of the reflected second harmonic is derived within the second-order *** analysis and numerical simulation indicate that the reflected second-harmonic amplitude increases sensitively with the increase in the nonlinear acoustic parameter of the plate material at some specific frequencies where the linear reflection coefficient of the normally incident longitudinal wave takes on the minimum value,and that it is independent of the spatial separation between the transmitter/receiver and the solid *** results obtained provide a means through which the early state of fatigue-induced damage of the solid plate(characterized by its nonlinear acoustic parameter)can be sensitively assessed by measuring the reflected second harmonic at the specific frequency where the linear reflection coefficient is minimum.

关键词： harmonic plate reflected

The measurement of the methanol concentration of liquid solution based on laser interferometer

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The measurement of the methanol concentration of liquid solu...

Simultaneous Detection and Removal of Formaldehyde at Room Temperature: Janus Au@ZnO@ZIF-8 Nanoparticles

2010 International Symposium on Computer,Communication, Control and Automation

作者： Yen-Liang Yeh Ming-Jyi Jang Chia-Hsing Shen Po-Jen Cheng Chih-Chia Wang department of Automation and Control engineering far east university department of mechanical engineering far east university

This study develops a high-precision,nondestructive measurement technique based on a laser interferometer for determining the methanol concentration of a liquid solution from its refractive *** optical metrology system is employed to measure the refractive indexes of samples with known methanol concentrations ranging from 0～90%.The error between the experimental refractive index and the literature refractive index is small than *** error between the measured value of the refractive index and the analytically derived value is reduced form 0.00064 to *** decreased error ratio is about 89%.When the relative function between the refractive index and methyl alcohol concentration is cubic,this can reduce the regressional analysis *** applying regressional analysis to the experimental results,an analytical expression is derived to describe the cubic relationship between the refractive index and the methanol *** excellent agreement is observed between the experimentally determined values of the methanol concentration and the analytically predicted results.

关键词： The measurement of the methanol concentration of liquid solution based on laser interferometer

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Nano-Micro Letters 2018年第1期10卷 34-44页

作者： Dawei Wang Zhiwei Li Jian Zhou Hong Fang Xiang He Puru Jena Jing-Bin Zeng Wei-Ning Wang department of mechanical & Nuclear engineering Virginia Commonwealth University department of Chemistry University of California department of Physics Virginia Commonwealth University College of Science China university of Petroleum (east China)

The detection and removal of volatile organic compounds(VOCs) are of great importance to reduce the risk of indoor air quality concerns. This study reports the rational synthesis of a dual-functional Janus nanostructure and its feasibility for simultaneous detection and removal of *** Janus nanostructure was synthesized via an anisotropic growth method, composed of plasmonic nanoparticles,semiconductors, and metal organic frameworks(e.g.,Au@ZnO@ZIF-8). It exhibits excellent selective detection to formaldehyde(HCHO, as a representative VOC) at room temperature over a wide range of concentrations(from 0.25 to100 ppm), even in the presence of water and toluene molecules as interferences. In addition, HCHO was also found to be partially oxidized into non-toxic formic acid simultaneously with detection. The mechanism underlying this technology was unraveled by both experimental measurements and theoretical calculations: ZnO maintains the conductivity, while ZIF-8 improves the selective gas adsorption; the plasmonic effect of Au nanorods enhances the visible-light-driven photocatalysis of ZnO at room temperature.

关键词： Indoor air quality Volatile organic compounds Janus structure Metal organic frameworks Plasmonic nanoparticles

Elastic field near the tip of an anticrack in a decagonal quasicrystalline material

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Applied Mathematics and Mechanics(English Edition) 2020年第3期41卷 401-408页

作者： Xu WANG P.SCHIAVONE School of mechanical and Power engineering East China University of Science and TechnologyShanghai 200237China department of mechanical engineering 10-203 Donadeo Innovation Centre for EngineeringUniversity of AlbertaEdmontonAlberta T6G 1H9Canada

We investigate the elastic field near the tip of an anticrack in a homogeneous decagonal quasicrystalline material subject to plane strain deformations. The phonon and phason stresses exhibit a square root singularity at the anticrack tip. Two realvalued phonon stress intensity factors and two real-valued phason stress intensity factors are introduced to scale four separate modes of deformation. We obtain four analytic functions which completely characterize the induced phonon and phason stresses as well as the displacement field. In particular, we derive a concise yet elegant representation of the anticrack contraction force.

关键词： decagonal quasicrystal anticrack elastic field anticrack contraction force analytic continuation

Three-dimensional electric potential induced by a point singularity in a multilayered dielectric medium

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Applied Mathematics and Mechanics(English Edition) 2019年第9期40卷 1327-1334页

作者： Xu WANG P. SCHIAVONE School of mechanical and Power engineering East China University of Science and Technology Shanghai 200237 China department of mechanical engineering University of Alberta 10-203 Donadeo Innovation Centre for Engineering Edmonton Alberta T6G 1H9 Canada

A simple and effective method is proposed to derive the three-dimensional electric potential induced by a point singularity of any type in an N-phase dielectric medium composed of N-2 intermediate dielectric layers of equal thickness encased in two semi-infinite dielectric media. The point singularity can include a point charge or a point electric dipole. The original boundary value problem for the N-phase medium is reduced to the determination of a single unknown three-dimensional harmonic function through satisfaction of the continuity conditions across all of the N-1 perfect planar interfaces. The single harmonic function can be completely determined after analytically solving the resulting linear recurrence relations, which are independent of the type and the specific location of the singularity. When the singularity is a point charge, we obtain the self-energy of the point charge expressed in terms of a single function and the Coulomb force on the point charge expressed in terms of the negative derivative of this function.

关键词： multilayered dielectric medium point charge point electric dipole linear recurrence relation analytical solution

Thermal-siphon phenomenon and thermal/electric conduction in complex networks

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National Science Review 2020年第2期7卷 270-277页

作者： Kezhao Xiong Zonghua Liu Chunhua Zeng Baowen Li State Key Laboratory of Precision Spectroscopy and department of Physics East China Normal University department of Physics University of Colorado Boulder Institute of Physical and engineering Sciences Faculty of Science Kunming University of Science and Technology department of mechanical engineering University of Colorado Boulder

In past decades, a lot of studies have been carried out on complex networks and heat conduction in regular lattices. However, very little attention has been paid to the heat conduction in complex networks. In this work, we study(both thermal and electric) energy transport in physical networks rewired from 2D regular lattices. It is found that the network can be transferred from a good conductor to a poor conductor,depending on the rewired network structure and coupling scheme. Two interesting phenomena were discovered:(i) the thermal-siphon effect—namely the heat flux can go from a low-temperature node to a higher-temperature node and(ii) there exits an optimal network structure that displays small thermal conductance and large electrical conductance. These discoveries reveal that network-structured materials have great potential in applications in thermal-energy management and thermal-electric-energy conversion.

关键词： complex network heat conduction non-linear dynamics thermoelectric properties

Determination of multiaxial stress rupture criteria for creeping materials:A critical analysis of different approaches

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Journal of Materials Science & Technology 2023年第6期137卷 14-25页

作者： Kun Zhang Jian-Ping Tan Wei Sun Kamran Nikbin Shan-Tung Tu Key Laboratory of Pressure Systems and Safety(Ministry of Education) School of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai200237China department of mechanical Materials and Manufacturing EngineeringUniversity of NottinghamNottinghamNG72RDUK department of mechanical engineering Imperial College LondonLondonSW72AZUK

Materials in engineering applications are rarely *** reality,failures under multiaxial loading has been widely observed in engineering *** life prediction of a component under multiaxial stresses has long been a challenging issue,particularly for high temperature *** distinguish the mode of failure ranging from a maximum principal stress intergranular damage to von Mises effective stress rupture mode a multiaxial stress rupture criterion(MSRC)was originally proposed by Sdobyrev and then Hayhurst and Leckie(SHL MSRC).A multiaxial-factor,α,was developed as a result which was intended to be a material constant and differentiates the bias of the MSRC between maxi-mum principal stress and effective *** success of the SHL MSRC relies on accurately calibrating the value ofαto quantify the multiaxial response of the material/geometry *** find a more suitable approach for determining MSRC,the applicability of different methods are *** that the resulting analysis of the various approaches can be affected by the creep failure mechanism,princi-ples in the determination of MSRC with and without using continuum damage mechanics approaches are *** viability of uniaxial material parameters in correlating withαthrough the analysis of available data in literature is also *** is found that the increase of the uniaxial creep dam-age tolerance parameterλis accompanied bythe decreaseof theα-value,whichimplies thatthe creep ductility plays an important role in affecting the multiaxial rupture behavior of materials.

关键词： Multiaxial stress rupture criterion Creep failure mechanism Uniaxial parameter Creep damage tolerance parameter Continuum damage mechanics

Modeling CO_(2) Emission of Middle eastern Countries Using Intelligent Methods

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Computers, Materials & Continua 2021年第12期69卷 3767-3781页

作者： Mamdouh El Haj Assad Ibrahim Mahariq Zaher Al Barakeh Mahmoud Khasawneh Mohammad Ali Amooie Sustainable and Renewable Energy engineering department University of SharjahPO Box 27272SharjahUAE College of engineering and Technology American University of the Middle EastKuwait department of mechanical and Industrial engineering Louisiana State UniversityUSA

CO_(2) emission is considerably dependent on energy consumption and on share of energy sources as well as on the extent of economic ***,these factors must be considered for CO_(2) emission prediction for seven middle eastern countries including Iran,Kuwait,United Arab Emirates,Turkey,Saudi Arabia,Iraq and *** order to propose a predictive model,a Multilayer Perceptron Artificial Neural Network(MLP ANN)is *** transfer functions including logsig,tansig and radial basis functions are utilized in the hidden layer of the ***,various numbers of neurons are applied in the structure of the *** is revealed that using MLP ANN makes it possible to accurately predict CO_(2) emission of these *** addition,it is concluded that using logsig transfer function leads to the highest accuracy with minimum value of mean squared error(MSE)which is followed by the networks with radial basis and tansig transfer *** R-squared of the networks with logsig,radial basis and tansig transfer functions are 0.9998,0.9997 and 0.9996,***,comparison of the proposed model with a similar study,considered five countries in the same region,reveals higher accuracy in term of MSE.

关键词： CO_(2)emission artificial neural network middle eastern countries transfer function

A Unified Petrov-Galerkin Spectral Method and Fast Solver for Distributed-Order Partial Differential Equations

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Communications on Applied Mathematics and Computation 2021年第1期3卷 61-90页

作者： Mehdi Samiee Ehsan Kharazmi Mark M.Meerschaert Mohsen Zayernouri department of mechanical engineering Michigan State UniversityEast LansingMI 48824USA department of Computational Mathematics Science and EngineeringMichigan State UniversityEast LansingMI 48824USA department of Probability and Statistics Michigan State UniversityEast LansingMI 48824USA

Fractional calculus and fractional-order modeling provide effective tools for modeling and simulation of anomalous diffusion with power-law *** complex multi-fractal anomalous transport phenomena,distributed-order partial differential equations appear as tractable mathematical models,where the underlying derivative orders are distributed over a range of values,hence taking into account a wide range of multi-physics from ultraslow-to-standard-to-superdiffusion/wave *** develop a unified,fast,and stable Petrov–Galerkin spectral method for such models by employing Jacobi poly-fractonomials and Legendre polynomials as temporal and spatial basis/test functions,*** defining the proper underlying distributed Sobolev spaces and their equivalent norms,we rigorously prove the well-posedness of the weak formulation,and thereby,we carry out the corresponding stability and error *** finally provide several numerical simulations to study the performance and convergence of proposed scheme.

关键词： Distributed Sobolev space Well-posedness analysis Discrete inf-sup condition Spectral convergence Jacobi poly-fractonomials Legendre polynomials