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Photonics Research 2019年第1期7卷 80-88页

作者： YUEYI YUAN KUANG ZHANG XUMIN DING BADREDDINE RATNI SHAH NAWAZ BUROKUR QUN WU Department of Microwave Engineering Harbin Institute of Technology State Key Laboratory of Millimeter Waves leme UPL Université Paris Nanterre

Polarization manipulation is a significant issue for artificial modulation of the electromagnetic(EM) wave, but general mechanisms all suffer the restriction of inherent symmetric properties between opposite ***, a strategy to independently and arbitrarily manipulate the EM wave with orthogonal circular polarizations based on a metasurface is proposed, which effectually breaks through traditional symmetrical characteristics between orthogonal handedness. By synthesizing the propagation phase and geometric phase, the appropriate Jones matrix is calculated to obtain independent wavefront manipulation of EM waves with opposite circular polarizations. Two transmissive ultra-thin meta-deflectors are proposed to demonstrate the asymmetrical refraction of transmitted circularly polarized waves in the microwave region. Simulated transmitted phase front and measured far-field intensity distributions are in excellent agreement, indicating that the transmitted wave with different polarizations can be refracted into arbitrary and independent directions within a wide frequency band(relative bandwidth of 25%). The results presented in this paper provide more freedom for the manipulation of EM waves, and motivate the realizations of various polarization-independent properties for all frequency spectra.

关键词： Polarization manipulation general mechanisms effectually breaks

Dielectric permittivity of dusty plasma in the Earth's mesosphere

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Earth and Planetary Physics 2021年第1期5卷 117-120页

作者： Hui Li Jian Wu National Key Laboratory of Electromagnetic Environment(leme) China Research Institute of Radio Wave PropagationQingdao 266109China

This paper deals with the dielectric permittivity of dusty plasma in the earth’s *** give expressions for the complex dielectric permittivity of dusty plasma,taking into account the effects of the dust charging process and magnetic *** discuss the dielectric permittivity of dusty plasma in several cases,such as high frequency approximation,parallel propagation in MF/HF band,and effects of plasma ***,the expressions are employed to study the phenomenon of radar echoes from the polar summer *** report that dielectric permittivity caused by the dust charging process gives a radar cross section proportional to ω–4 and produces a number density of charged dust that agrees with measurements of mesopheric radar echoes.

关键词： dusty plasma dielectric permittivity polar summer mesosphere

The Ritz-Sublaminate Generalized Unified Formulation approach for piezoelectric composite plates

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International Journal of Smart and Nano Materials 2018年第1期9卷 34-55,I0002页

作者： Michele D’Ottavio Lorenzo Dozio Riccardo Vescovini Olivier Polit leme UPLUniv Paris NanterreVille d’AvrayFrance Department of Aerospace Science and Technology Politecnico di MilanoMilanoItaly

This paper extends to composite plates including piezoelectric plies the variable kinematics plate modeling approach called Sublaminate Generalized Unified Formulation(SGUF).Two-dimensional plate equations are obtained upon defining a priori the through-thickness distribution of the displacement field and electric *** to SGUF,independent approximations can be adopted for the four components of these generalized displacements:an Equivalent Single Layer(ESL)or Layer-Wise(LW)description over an arbitrary group of plies constituting the composite plate(the sublaminate)and the polynomial order employed in each *** solution of the two-dimensional equations is sought in weak form by means of a Ritz *** this work,boundary functions are used in conjunction with the domain approximation expressed by an orthogonal basis spanned by Legendre *** proposed computational tool is capable to represent electroded surfaces with equipotentiality ***-vibration problems as well as static problems involving actuator and sensor configurations are *** case studies are presented,which demonstrate the high accuracy of the proposed Ritz-SGUF approach.A model assessment is proposed for showcasing to which extent the SGUF approach allows a reduction of the number of unknowns with a controlled impact on the accuracy of the result.

关键词： Piezoelectric composites variable kinematics model Ritz method unified formulation

CHIM-geoelectrochemical method in search of concealed mineralisation in China and Australia

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Chinese Journal Of Geochemistry 2008年第2期27卷 198-202页

作者： LUO Xianrong HOU Baohong WEN Meilanna ZENG Nanshi John Keeling Roger Fidler Adrian Fabris Guilin University of Technology Guilin 541004 China CRC leme Primary Industries ＆ Resources South Australia （PIRSA） SA 5000 Australia

A version of the geoelectrochemical prospecting technique developed in China was demonstrated in China and Australia to test its suitability under both Chinese and Australian *** paper briefly describes the mechanism and effectiveness of the technique applied to search of concealed mineralisation through regolith cover,based on both experimental and field *** paer deals with three main aspects of the method: a) how metallic ions are released from orebodies by electrochemical dissolution;b)how these ions migrate to the collector and are deposited as elements by electrochemical extraction in the presence of an electric field; and c) the effectiveness of the method illustrated by some case studies.

关键词：地球化学矿化作用中国澳大利亚

Detecting the meteoroid by measuring the electromagnetic waves excited by the collision between the hypervelocity meteoroid and spacecraft

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Plasma Science and Technology 2022年第11期24卷 70-77页

作者： Bo LIU Heng ZHANG Bin XU Zhengzheng MA Hui LI Wenshan DUAN College of Physics and Electronic Engineering Northwest Normal UniversityLanzhou 730070Peopleʼs Republic of China National Key Laboratory of Electromagnetic Environment(leme) China Research Institute of Radio Wave PropagationQingdao 266107Peopleʼs Republic of China

The electromagnetic pulse excited by the collision between a hypervelocity meteoroid and a spacecraft is studied both numerically and *** is found that there are two kinds of electromagnetic *** high-frequency electromagnetic pulse may be excited by the sum of all the electric *** electron can be considered as an electric *** low-frequency electromagnetic pulse is produced by the Langmuir oscillation of *** energy flux density and the duration time of the excited low-frequency electromagnetic pulse by the meteoroid are also studied in the present *** is shown that the energy flux density increases as either the impact speed or the mass of the meteoroid *** is also shown that the duration time decreases as both the impact speed and the mass of the meteoroid *** measuring the strength and the duration time of the electromagnetic pulse excited by the collision between the hypervelocity meteoroid and spacecraft,we can estimate the speed and the mass of the hypervelocity meteoroid,which will be helpful in space flight and space exploration.

关键词： plasma electromagnetic pulses hypervelocity impact PIC simulation

Effect of low cycle fatigue pre-damage on very high cycle fatigue

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Theoretical & Applied Mechanics Letters 2012年第3期2卷 23-26页

作者： Zhiyong Huang Qingyuan Wang Daniele Wagner Claude Bathias Department of Civil Engineering Sichuan UniversityChengdu 610064China leme University Paris 10Ville dAvray 92410France

Carbon-manganese steel is often applied in components of pipes in nuclear plant. Ultrasonic fatigue tests following low cycle fatigue （LCF） cycles damaged are used to study the strength of very high cycle fatigure （VHCF）. The comparison of test results of simple VHCF and cumulative fatigue （LCF plus VHCF） shows that LCF load influences the following VHCF strength. Continuum damage mechanics model is extended to VHCF region.

关键词： low cycle fatigue very high cycle fatigue continuum damage mechanics cumulative fatiguedamage

Simulation of DC glow discharge plasma with free-moving dust particles in the radial direction

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Plasma Science and Technology 2023年第9期25卷 73-81页

作者：田瑞焕梁勇敢郝书吉冯杰江晓楠李辉袁承勋吴健 National Key Laboratory of Electromagnetic Environment(leme) China Research Institute of Radio Wave PropagationQingdao 266170People’s Republic of China School of Physics Harbin Institute of TechnologyHarbin 150001People’s Republic of China

A self-consistent fluid model is developed to investigate the radial distributions of dusty plasma parameters in a DC glow discharge,in which the extended fluid approach of plasma particles and the transport equations of dust particles are *** electrical interaction between charged dust particles is considered in the *** time evolution of radial distributions of dust density,plasma density,the radial component of electric field and the forces acting on dust particles when dust density tends to be stable,are obtained and analyzed under different discharge currents and dust particle *** is shown that the dust density structure is determined mainly by the radial electrostatic force,thermophoretic force and ion drag force in the discharge tube,and both discharge current and dust particle radius have an obvious effect on the transport processes of dust *** dust particles gather in the central region of the discharge tube for low discharge current and small dust radius,then dust voids are formed and become wider when the discharge current and dust radius *** plasma parameters in the dust gathering region are obviously affected by the dust particles due to the charging processes of electrons and ions to the dust surface.

关键词： dusty plasma glow discharge extended fluid model dust transport processes dust-void

Theoretical research on the transport and ionization rate coefficients in glow discharge dusty plasma

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Plasma Science and Technology 2020年第3期22卷 17-23页

作者： Yonggan LIANG Jian WU Hui LI Ruihuan TIAN Chengxun YUAN Ying WANG Zhongxiang ZHOU Hao TIAN School of Physics Harbin Institute of TechnologyHarbin 150001People’s Republic of China National Key Laboratory of Electromagnetic Environment(leme) China Research Institute of Radio Wave PropagationBeijing 102206People’s Republic of China

The electron kinetic model for investigating the transport and ionization rate coefficients of argon glow discharge dusty plasma is developed from the Boltzmann *** of the electron-neutral and electron-dust collisions are considered as collision terms in the kinetic *** kinetic equation is simplified by employing the local approximation and nonlocal approach under the same discharge conditions,and the corresponding simplified kinetic equations are known as local and nonlocal kinetic equations *** the electron energy distribution function(EEDF)is obtained by numerically solving the local and nonlocal kinetic equations and the dust charging equations *** on the obtained EEDFs,the effective electron temperature,electron mobility,electron diffusion coefficient and ionization rate coefficient are calculated for different discharge *** is shown that the EEDFs calculated from the local kinetic model clearly differ from the nonlocal EEDFs and both the local and nonlocal EEDFs are also clearly different with Maxwellian *** appearance of dust particles results in an obvious decrease of high energy electrons and increase of low energy electrons when axial electric field is *** the increase of axial electric field,the influence of dust particles on the EEDFs becomes *** electron mobility and diffusion coefficients calculated on the basis of local and nonlocal EEDFs do not differ greatly to the dust-free ***,when dust density nd=10^6 cm^?3,the electron mobility increases obviously compared with the dust-free results at low axial electric field and decreases with the increasing axial electric field until they are close to the dust-free ***,electron diffusion coefficients for dusty case become smaller and decrease with the increasing axial electric *** ionization rate coefficients decrease when dust particles are introduced and they approach the dust-free results graduall

关键词： glow discharge dusty plasma kinetic model transport coefficient ionization rate coefficient

Composite wave-absorbing structure combining thin plasma and metasurface

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Plasma Science and Technology 2023年第4期25卷 148-155页

作者：郝志安李健飞徐彬姚静锋袁承勋王莹周忠祥王晓鸥 School of Physics Harbin Institute of TechnologyHarbin 150000People's Republic of China National Key Laboratory of Electromagnetic Environment(leme) China Research Institute of Radio Wave PropagationQingdao 266107People's Republic of China Heilongjiang Provincial Key Laboratory of Plasma Physics and Technology Harbin 150000People's Republic of China

In order to solve the thickness dependence of plasma absorption of electromagnetic waves and further reduce the backward radar scattering cross section(RCS)of the target,we designed a novel composite structure of a metasurface and plasma.A metasurface with three absorption peaks is designed by means of an equivalent circuit based on an electromagnetic resonance type metamaterial *** reflection and absorption of the composite structure are numerically and experimentally *** finite integration method was used to simulate a composite structure of finite size to obtain the *** experimental measurements of electromagnetic wave reflection were conducted by a vector network analyzer(Keysight N5234A)and horn antennas,*** research showed that the absorption capacity of this composite structure was substantially improved compared to either the plasma or the metasurface,and it is more convenient for application due to its low plasma thickness requirement and easy fabrication.

关键词： plasma metasurface composite structure radar scattering cross section

Dual-band independent phase control based on high efficiency metasurface[Invited]

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Chinese Optics Letters 2021年第10期19卷 7-14页

作者： Jinxing Li Yueyi Yuan Qun Wu Shah Nawaz Burokur Kuang Zhang Department of Microwave Engineering Harbin Institute of TechnologyHarbin 150001China leme UPLUniversite Paris NanterreF92410 Ville d'AvrayFrance

A general method to realize arbitrary dual-band independent phase control is proposed and demonstrated in this paper.A double-layered C-shape reflective meta-atom is designed to realize independent phase control with high *** a proof of concept,we propose two functional metasurfaces in the microwave region;the first metasurface performs beam steering in different directions,and the second metasurface generates achromatic beam steering at two distinct *** simulation and measurement results agree well with the theoretical *** maximum measured efficiency is 88.7%and 92.3%at 6.8 GHz and 8.0 GHz,respectively,for one metasurface,and 91.0%and 89.8%at 6.9 GHz and8.6 GHz,respectively,for the other.

关键词： dual-band independent phase control microwave metasurface high efficiency reflection geometric phase