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magnetohydrodynamic flows tuning in a conduit with multiple channels under a magnetic field applied perpendicular to the plane of flow

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Journal of Hydrodynamics 2017年第2期29卷 332-343页

作者： Y.Luo C.N.Kim m.q.Zhu Department of mechanical Engineering Graduate SchoolKyung Hee UniversityYong-inKorea Department of mechanical Engineering College of EngineeringKyung Hee UniversityYong-inKorea

In this study, three-dimensional liquid-metal magnetohydrodynamic flows in a conduit with multiple channels under a uniform magnetic field are numerically investigated. The geometry of the conduit is of a four-parallel-channels system including one inflow channel and three outflow channels. The liquid-metal flows into the inflow channel, then turns through 180° in the transi- tion segment, finally flows into three different outflow channels. This kind of channel system can induce counter flow and co-flow, which is rarely investigated before though the conceptual designs of duct flow in the blanket have suggested this type of flow. A structured grid system is chosen after a series of mesh independence tests in the present study. The axial velocity in the side layer near the first partitioning wall, located between the inflow channel and the first outflow channel, is the highest with the lowest electric potential formed therein. The pressure almost linearly decreases in the main flow direction, except in the transition segment. moreover, the pressure gradient in the first outflow channel is the largest among the three outflow channels. The interdependency of the current, fluid velocity, pressure, electric potential is examined in order to describe the electromagnetic characteristics of the liquid-metal flows.

关键词： Liquid-metal magnetohydrodynamics multiple channels

The role of microRNAs in human cancer

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Signal Transduction and Targeted Therapy 2016年第1期1卷 149-157页

作者： Yong peng Carlo m Croce Department of Thoracic Surgery State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengduChina Collaborative Innovation Center of Biotherapy ChengduChina Department of molecular Virology Immunology and Medical GeneticsComprehensive Cancer CenterThe Ohio State UniversityColumbusOHUSA

microRNAs(miRNAs)are endogenous,small non-coding RNAs that function in regulation of gene *** evidences have demonstrated that miRNA expression is dysregulated in human cancer through various mechanisms,including amplification or deletion of miRNA genes,abnormal transcriptional control of miRNAs,dysregulated epigenetic changes and defects in the miRNA biogenesis *** may function as either oncogenes or tumor suppressors under certain *** dysregulated miRNAs have been shown to affect the hallmarks of cancer,including sustaining proliferative signaling,evading growth suppressors,resisting cell death,activating invasion and metastasis,and inducing *** increasing number of studies have identified miRNAs as potential biomarkers for human cancer diagnosis,prognosis and therapeutic targets or tools,which needs further investigation and *** this review,we focus on how miRNAs regulate the development of human tumors by acting as tumor suppressors or oncogenes.

关键词： expression. cancer invasion

magnetism,optical,and thermoelectric response of CdFe_2O_4by using DFT scheme

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Chinese Physics B 2018年第3期27卷 376-383页

作者： q.m.hmood m Yaseen K C Bhamu Asif mahmood Y Javed Shahid m Ramay materials Growth and Simulation Laboratory Department of PhysicsUniversity of the Punjab Department of Physics University of AgricultureFaisalabad Department of Physics Goa University Chemical Engineering Department College of Engineering King Saud University Physics and Astronomy Department College of Science King Saud University

Comparative analysis of electronic, magnetic, optical, and thermoelectric properties of CdFe2O4, calculated by em- ploying PBEsol ＋ mBJ has been done. The PBEsol reveals metallic nature, while TB-mBJ illustrates ferromagnetic semiconducting behavior. The reasons behind the origin of ferromagnetism are explored by observing the exchange, crystal field, and John-Teller energies. The optical nature is investigated by analyzing dielectric constants, refraction, absorption coefficient, reflectivity, and optical conductivity. Finally, thermoelectric properties are elaborated by describing the electri- cal and thermal conductivities, Seebeck coefficient, and power factor. The strong absorption for the visible energy and high power factor suggest CdFe2O4 as the potential candidate for renewable energy applications.

关键词： frustrated magnetism density functional theory John-Teller distortion Hund's rule

Numerical study on the resistance of rigid projectiles penetrating into semi-infinite concrete targets

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Acta mechanica Sinica 2021年第3期37卷 482-493,I0003页

作者： Huawei Yang Jie Zhang Zhiyong Wang Zhihua Wang q.m.Li College of management Science and Engineering Shanxi University of Finance and EconomicsTaiyuan 030006China Institute of Applied mechanics College of Mechanical and Vehicle EngineeringTaiyuan University of TechnologyTaiyuan 030024China Shanxi Key Laboratory of material Strength and Structural Impact Taiyuan University of TechnologyTaiyuan 030024China Department of mechanical Aerospace and Civil EngineeringSchool of EngineeringThe University of ManchesterManchester M139PLUK

A study on the resistance of rigid projectiles penetrating into semi-infinite concrete targets is performed in this *** data are analyzed to examine the penetration resistance during various stages of the penetration process.A numerical tool using AUTODYN hydrocode is applied in the *** numerical results on both deceleration-time history and depth of penetration of projectiles are in good agreement with experimental data,which demonstrate the feasibility of the numerical model in these *** on the numerical model with a two-staged pre-drilled hole,the rigid projectile penetration in tunneling stage is studied for concrete targets with different strengths in a wide range of impact *** results show that the penetration in tunnel stage can be divided into two different cases in terms of initial impact *** the first case,when the impact velocity is approximately less than 600 m/s,the deceleration depends on initial impact *** the second case,when the impact velocity is greater than 600 m/s,the effect of target inertia becomes apparent,which agrees with commonly used concrete penetration resistance equations based on cavity expansion model.

关键词： Rigid projectile Penetration resistance Entrance phase Inertial term Concrete target

TiZr-base Bulk metallic Glass with over 50 mm in Diameter

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Journal of materials Science & Technology 2010年第6期26卷 481-486页

作者： m. q. Tang H.F. Zhang Z. W. Zhu H.m. Fu A.m. Wang H. Li Z.q. Hu Shenyang National Laboratory for materials Science Institute of Metal Research Chinese Academy of Sciences 72Wenhua Road Shenyang 110016 China

Low-cost TiZr-base bulk metallic glasses （BmGs）（Ti36.1Zr33.2Ni5.8Be24.9）100-xCux （x=5, 7 and g） with a maximum size of over 50 mm in diameter were developed by optimizing the alloy composition. The idea is initiated by selecting a particular microstructure comprising primary β-Ti dendrite and amorphous phase. Afterwards, based on this composition of amorphous phase, a class of TiZr-base bulk metallic glasses was designed step by step to reach the optimum composition range. The glass transition temperature （Tg）, initial crystallization temperature （Tx） and width of supercooled region （AT） of （***33.2Nis.8Be24.9）91Cu9 BmG are 611, 055 and 44 K, respectively. The （Ti36.1Zr33.2Ni5.8Be24.9）91Cu9 BmG exhibits low density of 5.541 g·cm-3 and high compressive fracture strength of 1800 mPa, which promises the potential application as structural materials.

关键词： TiZr-base alloy Bulk metallic glass (BmG) Fracture strength

Vibration characteristics of piezoelectric functionally graded carbon nanotube-reinforced composite doubly-curved shells

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Applied mathematics and mechanics(English Edition) 2021年第6期42卷 819-840页

作者： V.V.THAm H.q.TRANT T.m.TU National Univensity of Ciwil Engineering Giai Phong Road 55Hai Ba Trung DistrictHanoi 100000 Vietnam

This paper presents an analytical solution for the free vibration behavior of functionally graded carbon nanotube-reinforced composite(FG-CNTRC) doubly curved shallow shells with integrated piezoelectric layers. Here, the linear distribution of electric potential across the thickness of the piezoelectric layer and five different types of carbon nanotube(CNT) distributions through the thickness direction are considered. Based on the four-variable shear deformation refined shell theory, governing equations are obtained by applying Hamilton's principle. Navier's solution for the shell panels with the simply supported boundary condition at all four edges is derived. Several numerical examples validate the accuracy of the presented solution. New parametric studies regarding the effects of different material properties, shell geometric parameters, and electrical boundary conditions on the free vibration responses of the hybrid panels are investigated and discussed in detail.

关键词： free vibration four-variable shear deformation refined theory functionally graded carbon nanotube-reinforced composite(FG-CNTRC) piezoelectric material

Analysis of extreme ultraviolet spectral profiles of laser-produced Cr plasmas

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Chinese Physics B 2019年第7期28卷 319-323页

作者： L Wu m G Su q.m.n S q Cao S q He D X Sun C Z Dong Key Laboratory of Atomic and molecular Physics & Functional material of Gansu Province College of Physics and Electronic EngineeringNorthwest Normal University

Radiation from laser-produced plasmas was examined as a potential wavelength calibration source for spectrographs in the extreme ultraviolet(EUV) ***, the EUV emission of chromium(Cr) plasmas was acquired via spatiotemporally resolved emission *** the aid of Cowan and flexible atomic code(FAC) structure calculations,and a comparative analysis with the simulated spectra, emission peaks in the 6.5–15.0 nm range were identified as 3 p–4 d, 5 d and 3 p–4 s transition lines from Cr5+–Cr10+ions.A normalized Boltzmann distribution among the excited states and a steady-state collisional-radiative model were assumed for the spectral simulations, and used to estimate the electron temperature and density in the *** results indicate that several relatively isolated emission lines of highly charged ions would be useful for EUV wavelength calibration.

关键词： laser-produced plasmas highly charged ions extreme ultraviolet wavelength calibration

Harmonic balance-based approach for optimal time delay to control unstable periodic orbits of chaotic systems

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Acta mechanica Sinica 2020年第4期36卷 918-925页

作者： Y.m.Chen q.X.Liu J.K.Liu Department of mechanics Sun Yat-sen UniversityGuangzhou 510275China

As a classical technique for chaos suppression,the time-delayed feedback controlling strategy has been widely developed by stabilizing unstable periodic orbits(UPOs)embedded in chaotic systems.A critical issue for achieving high controlling precision is to search for an appropriate time *** paper proposes a simple yet effective approach,based on incremental harmonic balance method,to determine the optimal time delay in the delayed feedback *** time delay is adjusted within the iterative scheme provided by the proposed method,and finally converges to the period of the target *** long as the optimal time delay is fixed,moreover,the attained solution makes it quite convenient to analyze its stability according to the Floquet theory,which further provides the effective interval of the feedback gain.

关键词： Chaos control Unstable periodic orbit Delayed feedback Optimal time delay Incremental harmonic balance method

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Guest editorial

Digital Communications and Networks 2020年第3期6卷 239-240页

作者： Tao Jiang Tony q.S.quek Zhiguo Ding mugen peng Yun Li Huazhong University of Science&Technology China Singapore University of Technology and Design Singapore University of manchester UK Beijing University of Posts&Telecommunications China Chongqing university of Posts and Telecommunications China

With the rapid deployment of 5G communication networks,the sixthgeneration(6G)mobile network has attracted extensive attention from academia,industry,and government agencies,devoting to identifying critical drivers,performance requirements,and technological *** progress of 6G networks in enhanced mobile broadband,massive machine-type communications and ultra-reliable and lowlatency communications will promote the fast development of new services,e.g.,Augmented Reality(AR),Virtual Reality(VR),holographic communications,Vehicle-to-Everything(V2X),self-driving cars,massive *** services would have different features and *** order to adapt to the ever-changing services,6G should not only be intelligent and open to support full broadband services,but also enhance its capabilities compared with *** will challenge 6G from various aspects,such as rate,delay,coverage,access,energy consumption,interaction,reliability,and degree of intelligence.

关键词： services massive networks