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Thermal Equilibrium Reached by Interaction Between Two Identical Systems

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Communications in Theoretical Physics 2008年第6期49卷 1461-1462页

作者： fu liang FAN Hong-Yi Department of Material Science and Engineering University of Science and Technology of China Hefei 230026 China Depatrment of Physics Shanghai Jiao Tong University Shanghai 200030 China

In this work we show that tending to thermal equilibrium in one system, at least in certain cases, is associated with the coherent dynamical evolution of this system in interaction with another identical system. The t... 详细信息

关键词： thermal equilibrium temperature coherent dynamic evolution

Quadrature-free spline method for two-dimensional Navier-Stokes equation

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Applied Mathematics(A Journal of Chinese Universities) 2008年第1期23卷 31-42页

作者： HU Xian-liang HAN Dan-fu Dept. of Math. Zhejiang Univ. Hangzhou 310027 China.

In this paper, a quadrature-free scheme of spline method for two-dimensional Navier- Stokes equation is derived, which can dramatically improve the efficiency of spline method for fluid problems proposed by Lai and Wenston（2004）. Additionally, the explicit formulation for boundary condition with up to second order derivatives is presented. The numerical simulations on several benchmark problems show that the scheme is very efficient.

关键词： quadrature-free spline method Navier-Stokes equation.

Complex Wave Solutions for (2+1)-Dimensional Modified Dispersive Water Wave System

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Communications in Theoretical Physics 2009年第7期52卷 17-22页

作者： liang Jin-fu GONG Lun-Xun School of Physics and Electronic Science Guizhou Normal University Guiyang 550001 China

The extended Riccati mapping approach^[1] is further improved by generalized Riccati equation, and combine it with variable separation method, abundant new exact complex solutions for the （2＋1）-dimensional modified dispersive water-wave （MDWW） system are obtained. Based on a derived periodic solitary wave solution and a rational solution, we study a type of phenomenon of complex wave.

关键词： MDWW system generalized Riccati equation variable separation method complex wave

Topological crystalline insulator nanomembrane with strain-tunable band gap

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Nano Research 2015年第3期8卷 967-979页

作者： Xiaofeng Qian liang fu Ju Li Department of Nuclear Science and Engineering and Department of Materials Science and Engineering Massachusetts Institute of Technology Cambridge Massachusetts 02139 USA Department of Physics Massachusetts Institute of Technology Cambridge Massachusetts 02139 USA

The ability to fine-tune band gap and band inversion in topological materials is highly desirable for the development of novel functional devices. Here we propose that the electronic properties of free-standing nanomernbranes of the topological crystalline insulators （TCI） SnTe and Pb1-xSnx（Se,Te） are highly tunable by engineering elastic strain and membrane thickness, resulting in tunable band gap and giant piezoconductivity. Membrane thickness governs the hybridization of topological electronic states on opposite surfaces, while elastic strain can further modulate the hybridization strength by controlling the penetration length of surface states. We propose a frequency-resolved infrared photodetector using force-concentration induced inhomogeneous elastic strain in TCI nanomembranes with spatially varying width. The predicted tunable band gap accompanied by strong spin-textured electronic states will open new avenues for fabricating piezoresistive devices, infrared detectors and energy-efficient electronic and spintronic devices based on TCI nanomembrane.

关键词： elastic strain engineering pseudoheterostructure infrared photodetector metal-insulatortransition DFT calculations

Tunable Weyl fermions and Fermi arcs in magnetized topological crystalline insulators

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Chinese Physics B 2019年第4期28卷 41-46页

作者： Junwei Liu Chen Fang liang fu Department of Physics Hong Kong University of Science and Technology (HKUST) Department of Physics Massachusetts Institute of Technology Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences

Based on k · p analysis and realistic tight-binding calculations, we find that time-reversal-breaking Weyl semimetals can be realized in magnetically-doped(Mn, Eu, Cr, etc.) Sn_(1-x)Pb_x(Te, Se) class of topological crystalline insulators. All the Weyl points are well separated in momentum space and possess nearly the same energy due to high crystalline ***, both the Weyl points and Fermi arcs are highly tunable by varying Pb/Sn composition, pressure, magnetization,temperature, surface potential, etc., opening up the possibility of manipulating Weyl points and rewiring the Fermi arcs.

关键词： topological crystalline insulator magnetic Weyl semimetal magnetically-doped Sn1-x Pbx(Te,Se) Fermi arc

Synthesis and Mesomorphic Properties of Novel γ-Substituted β-Diketonates

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Chinese Chemical Letters 2004年第2期15卷 155-158页

作者： Jie HAN liang fu ZHANGWen WAN lDepartment of Chemistry Nankai UniversityTianjin 300071 Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041

The synthesis and mesomorphic properties of two series of novel -substituted -diketonates have been reported. All of the compounds 2,4-dioxo-3-pentyl 4-[[4-(n-alkoxyl) cinnamoyl]oxy]cinnamatetes Ia-If (n=7-12) exhibit two monotropic phases(N and Sc) and have a wider mesophase range than the compounds 2,4-dioxo-3-pentyl 4-[[4-(n-alkoxyl) benzoyl]oxy] cinnamatetes IIa-IIf (n=7-12), which display one monotropic nematic phase (n=7-10) or an enantiotropic nematic phase for n=11 or two enantiotropic phases (N and Sc) for n=12 .

关键词： γ-Substituted β-diketonates Liquid crystal Synthesis

Characterization of Tensile Strain Hardening Behaviors for 32Mn-7Cr-1Mo-0.3N Cryogenic Austenitic Steel

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Journal of Materials Science & Technology 2006年第5期22卷 629-633页

作者： liang QIU Ruidong fu Cunyu WANG Yangzeng ZHENG Key Laboratory of Metastable Materials Science and Technology College of Materials Science and EngineeringYanshan University Qinhuangdao 066004 China

The strain hardening behaviors of 32Mn-TCr-1Mo-0.3N austenitic steel were characterized by a simple and effective method. The results show that Hollomon relationship is not applicable during total uniform deformation stage. The flow equation was proposed, Inσ=αexp（lnε/b）＋c. The variation rates of strain hardening exponents with true strain at 77 K are obviously higher than that at other temperatures and the value of d^2σ/dε^2 becomes positive during high strain stage. The characters of this variation are principal reasons for increasing elongation at 77 K. The forming of mechanical twin as well as ε-martensite leads to a high elongation at 77 K.

关键词： High manganese autenitic steel Nitrogen strengthening Strain hardening exponent Strain hardening rate Deformation structure

Research on Feature Extraction of Remnant Particles of Aerospace Relays

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Chinese Journal of Aeronautics 2007年第3期20卷 253-259页

作者： WANG Shu-juan GAO Hong-liang ZHAI Guo-fu Department of Electrical Engineering Harbin Institute of Technology Harbin 150001 China

The existence of remnant particles, which significantly reduce the reliability of relays, is a serious problem for aerospace relays. The traditional method for detecting remnant particles-particle impact noise detection （PIND）-can be used merely to detect the existence of the particle; it is not able to provide any information about the particles＇ material. However, information on the material of the particles is very helpful for analyzing the causes of remnants. By analyzing the output acoustic signals from a PIND tester, this paper proposes three feature extraction methods： unit energy average pulse durative time, shape parameter of signal power spectral density （PSD）, and pulse linear predictive coding coefficient sequence. These methods allow identified remnants to be classified into four categories based on their material. furthermore, we prove the validity of this new method by processing P1ND signals from actual tests.

关键词： feature extraction aerospace relays remnant particles particle impact noise detection

Electro-catalytic degradation properties of Ti/SnO_2–Sb electrodes doped with different rare earths

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Rare Metals 2016年第5期35卷 412-418页

作者： fu-liang Zhu Yan-Shuang Meng Xiu-Yang Huang State Key Laboratory of Gansu Advanced Nonferrous Metal Materials Lanzhou University of Technology School of Materials Science and Engineering Lanzhou University of Technology

Ti/SnO2–Sb electrode has a good effect on the removal of organic pollutants. But its short service life limits its large-scale application in industry. Electro-catalytic degradation performances and service life of the electrode can be significantly improved by doping rare earth（RE） ions into the oxide coating of Ti/SnO2–Sb electrode. Ti/SnO2–Sb electrodes doped with different RE elements（Ce, Dy, La, and Eu） were prepared by the thermal decomposition method at 550 ℃. Electro-catalytic degradation performances of electrodes doped with different RE elements were evaluated by linear sweep voltammetry（LSV） and Tafel curves. During the electrolysis,the conversion of p-nitrophenol was performed with these electrodes as anodes under galvanostatic control. The structures and morphologies of the surface coating of the electrodes were characterized by scanning electron microscope（SEM）. The results demonstrate that the electro-catalytic degradation performances of Ti/SnO2–Sb electrodes are improved to different levels by doping different RE ions. Improved Ti/SnO2–Sb electrodes by the introduction of different RE have higher oxygen evolution potential, better electro-catalysis ability, better coverage,and longer electrode life.

关键词： Ti/SnO_2–Sb electrode Rare earth doped Thermal decomposition method Catalytic degradation