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Free control of far-field scattering angle of transmission terahertz wave using multilayer split-ring resonators'metasurfaces

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Frontiers of physics 2020年第6期15卷 125-132页

作者： Ying Tian Xufeng Jing Haiyong gan Chenxia Li Zhi hong Institute of Optoelectronic Technology China Jiliang UniversityHangzhou 310018China National Institute of Metrology Beijing 102200China

To enhance transmission eficiency of Pancharatnam Berry(PB)phase metasurfaces,multilayer split-ring resonators were proposed to develop encoding *** per the generalized Snell's law,the deflection angle of the PB phase encoding metasurfaces depends on the metasurface period's ***,it is impossible to design an infinitesimal metasurface unit;consequently,the continuous transmission scattering angle cannot be *** digital signal processing,this study introduces the Fourier convolution principle on encoding metasurface sequences to freely control the trausmitted scattering *** addition and subtraction operations between two diferent encoding sequences were then performed to achieve the continuous variation of the scattering ***,we established that the Fourier convolution principle can be applied to the checkerboard coded metasur-faces.

关键词： metamaterial metasurface scattering Fourier convolution

Effects of Normalizing Annealing on Grain-oriented Silicon Steel

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Journal of Iron and Steel Research International 2014年第7期21卷 690-694页

作者： Chen LING Li XIANG Sheng-tao QIU yong gan State Key Laboratory of Advanced Steel Processing and Products National Engineering Research Center of Continuous Casting TechnologyCentral Iron and Steel Research Institute

The grain-oriented silicon steel is a kind of important magnetic materials with low iron loss and high induc tion. Hot hand normalizing annealing is an important process which influences the microstructure and the development of the inhibitors. The effects of different annealing temperatures and cooling conditions on the inhibitors and microstructures of normalizing annealing band were investigated. The microstructure and different kinds of the inhibitors, i. e. , A1N, AIN＋Cu, S＋MnS, and TiN, were discovered. The result shows that a suitable cooling condition leads to more nano scale inhibitors and uniform microstructure of the normalizing annealing band and consequently results in better magnetic properties.

关键词： grain-oriented silicon steel normalizing annealing microstructure inhibitor

Numerical Simulation of Heat Transfer and Deformation of Initial Shell in Soft Contact Continuous Casting Mold Under High Frequency Electromagnetic Field

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Journal of Iron and Steel Research International 2007年第6期14卷 14-21页

作者： NA Xian-zhao XUE Min ZHANG Xing-zhong gan yong State Key Laboratory of Advanced Steel Processes and Materials Central Iron and Steel Research Institute Beijing 100081 China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

Heat transfer and deformation of initial solidification shell in soft contact continuous casting mold under high frequency electromagnetic field were analyzed using numerical simulation method; the relative electromagnetic parameters were obtained from the previous studies. Owing to the induction heating of a high frequency electromagnetic field （20 kHz）, the thickness of initial solidification shell decreases, and the temperature of strand surface and slit copper mold increases when compared with the case without the electromagnetic filed. The viscosity of flux de- creases because of the induction heating of the high frequency electromagnetic field, and the dimension of the flux channel increases with electromagnetic pressure; thus, the deformation behavior of initial solidification shell was different before and after the action of high frequency electromagnetic field. Furthermore, the abatement mechanism of oscillation marks under high frequency electromagnetic field was explained.

关键词： soft contact electromagnetic continuous casting mold heat transfer ~ initial solidification~ elastic-plasticdeformation finite element method numerical simulation

Experimental Investigation of the Mg–Zn–Zr Isothermal Section at 400 °C

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Acta Metallurgica Sinica(English Letters) 2019年第4期32卷 426-432页

作者： yong-Peng Liang Shu-hong Liu Kai Xu yong Du State Key Lab of Powder Metallurgy Central South University School of Materials Science and Engineering Central South University

Mg-Zn-Zr series Mg alloys(ZK) are one of the most important commercial Mg alloys due to their good comprehensive mechanical properties. The phase equilibria of the Mg-Zn-Zr system at 400 ℃ covering the overall composition range were investigated by X-ray diffraction and electron probe microanalyses on thirteen ternary alloys. Three ternary compounds, τ_1, τ_2 and τ_3, were detected to be thermodynamically stable at 400 ℃, and their homogeneity range was determined to be Mg_((7-17))Zn_((80-88))Zr_((4-6)), Mg_((15-22))Zn_((66-65))Zr_((9-16)) and Mg_9 Zn_(68)Zr_(23)(in at.%), respectively. Eight three-phase regions and four two-phase regions were observed. The maximum solubility of Mg in Zn_(22) Zr, Zn_(39) Zr_5 and Zn_3 Zr phases was measured to be 0.52, 0.37 and 0.99 at.%, respectively, while the solubility of Zr in MgZn_2 and Mg_2 Zn_3 phases is negligible. The isothermal section of the Mg-Zn-Zr system at 400 ℃ was then constructed based on the present experimental data.

关键词： Mg–Zn–Zr Isothermal section Phase equilibria Ternary compounds

Density Functional Theory Study of Infrared and Ultraviolet Spectra of Urea L-Malic Acid

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Chinese Journal of Chemical Physics 2008年第6期21卷 535-540页

作者： Yan-lan Zhang hong-yan Wang Dong-sheng Jiao yong-hong Hu Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China College of Sciences Southwest Jiaotong University Chengdu 610031 China College of Life Science and Pharmaceutical Engineering Nanjing University of Technology Nanjing 210009 China

Urea L-malic acid, a new second order nonlinear optical crystal, was studied using density functional theory （DFT）. PBEPBE/6-31＋G（d,p） method, the optimal method for comparing the results from the several DFT methods, was chosen to study the molecular structure. Infrared and ultraviolet-visible spectra were obtained and compared with experiments. The ultraviolet-visible spectrum was also analyzed by the molecular orbital population. The geometries, and the infrared and ultraviolet-visible spectra in water were studied using DFT methods in combination with the polarized continuum model to predict the perturbations by the solvent effect.

关键词： Urea L-malic acid Density functional theory Molecular structure Infrared spectrum Ultraviolet-visible spectrum

Developmental Characteristics and Cinnamic Acid Resistance of Root Border Cells in Cucumber and Figleaf Gourd Seedlings

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Journal of Integrative Agriculture 2013年第11期12卷 2065-2073页

作者： QIAO yong-xu ZHANG yong-ping ZHANG hong-xin TIAN yong-qiang GAO Li-hong Department of Vegetable Science China Agriculture University/Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops Department of Life Science Tangshan Normal University

Root border cells （RBCs） originate from the root tip epidermis and surround the root apices. In this study, we evaluated the developmental characteristics and the roles of RBCs in protection of root apices of cucumber and ifgleaf gourd seedlings from CA toxicity. The formation of RBCs and the emergence of the root tip occurred almost simultaneously in root apices of cucumber and ifgleaf gourd seedlings. CA ranging from 0 to 0.25 mol L-1 inhibited root elongation and decreased root cell viability in the root tip, moreover the inhibitory effects of CA were more signiifcant in the CA-sensitive cucumber than in the CA-tolerant ifgleaf gourd. Removal of RBCs from root tips led to more severe CA induced inhibition of root elongation and decline in root cell viability. Increasing CA levels and treatment time decreased the relative viability of attached and detached RBCs. CA also induced a thicker mucilage layer surrounding attached RBCs of both species. Additionally, a signiifcantly higher relative cell viability of attached RBCs and thicker mucilage layers were observed in ifgleaf gourd. These results suggest that RBCs play an important role in protecting root tips from CA toxicity.

关键词： cinnamon acid autotoxicity root border cells cell viability

Study Hankel Transforms and Properties of Bessel Function via Entangled State Representation Transformation in Quantum Mechanics

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Communications in Theoretical Physics 2006年第5期45卷 819-824页

作者： FAN hong-Yi WANG yong Department of Material Science and Engineering University of Science and Technology of China Hefei 230026 China Department of Physics Shanghai Jiao Tong University Shanghai 200030 China Department of Special Class for Gifted Young University of Science and Technology of China Hefei 230026 China

In Phys. Lett. A 313 （2003） 343 we have found that the self-recipràcal Hankel transformation （HT） is embodied in quantum mechanics by a transform between two entangled state representations of continuum variables. In this work we study Hankel transforms and properties of Bessel function via entangled state representations＇ transformation in quantum mechanics.

关键词： entangled state representation Hankel transform Bessel function

Review on effect of applied internal cooling source and vibration on metal solidification process

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Journal of Iron and Steel Research International 2023年第6期30卷 1059-1072页

作者： Yu-chao Yao Miao Liu Zhong-qiu Liu Bao-kuan Li yong gan Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina China Iron&Steel Research Institute Group Co. Ltd.Beijing 100081China

Advancements in metallurgical technology have led to the emergence of high-performance requirements for metal materials,like high uniformity,high purity,and superfine *** has resulted in the development and application of internal cooling source(ICS),vibrational,and vibrational internal cooling source methods in metal solidification processes to afford products with refined crystal grains and large proportions of equiaxed *** methods have gradually been introduced into laboratories and some steel mills over the past few ***,there are few successful industrial applications of these methods,as there is no comprehensive understanding of their control theories and ***,the development,basic principles,and classifications of the three types of methods are summarized,and their impact on the solidification of molten metals and the morphology of solid products is *** addition,experimental and numerical simulation-based researches on each type of method are reviewed and their prospects for applications are briefly discussed to control metal ***,detailed future perspectives are provided on vibratory strip feeding,ICS,and pulsed magneto-oscillation ***,it will serve as a reference for future studies of the application of these and related methods in metal solidification processes.

关键词： Internal cooling source Vibration Solidification Strip feeding Grain refinement

Effect of Water Vapor on O^(2-) Content in Ironmaking Slag

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Journal of Iron and Steel Research International 2015年第10期22卷 909-915页

作者： Yousef MOHASSAB hong-yong SOHN Department of Metallurgical Engineering University of Utah

In principle, slag basicity can be expressed as the concentration of free oxygen （O^2-） in the slag system. This free oxygen content is equilibrated with different silicate anions in addition to other components in the silicate-based slags. X-ray photon spectroscopy （XPS） and scanning electron microscope equipped with energy dispersive spectrometer （SEM-EDS） were used to investigate the effect of water vapor on the free oxygen content in ironmaking slags. It was found that water in the gas atmosphere plays a significant role in the silicate anion equilibria. Water decreases the amount of free oxygen in the studied slags, with the free oxygen expressed as percentage of the total oxygen decreasing in the order of the following gas mixtures： CO＋CO2 （44%, PH2O = 0 kPa）〉 CO＋CO2＋H2＋H2O （41%, PH2O = 10.13 kPa）〉 H2＋H2O （37%, PH2O = 14.19 kPa）. The content of free oxygen ion affects the distribution of elements such as sulfur, phosphorus, and manganese. In addition, it affects the iron oxide content in the slag as well as the interaction between slag and furnace lining.

关键词： flash ironmaking ironmaking slag slag chemistry basicity water