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THE ACqM THEORETICAL CALCULATION OF LOW-LYINg EXCITED STATES FOR HeH

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原子与分子物理学报 1990年第4期7卷 1565-1570页

作者： q.q.gOU z.Y.Huang 等 TheIustituteofAtomicandMolecularPhysics ChengduUniversityofScienceandTechnologyChengduChina TheIust

The Low-lying excited states of HeH have been calculated by arrangement channel quantum mechanics(ACqM),The calculated potential curves,equilibrium geometry,*** energy *** vibration frequency ω0 and quadratic force c... 详细信息

关键词： HeH 低激发态 ACqM理论计算

Effects of chemical pressure on diluted magneticsemiconductor(Ba,K)(zn,Mn)_2As_2

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Chinese Physics B 2019年第5期28卷 288-292页

作者： Y Peng S Yu g q zhao W M Li J F zhao L P Cao X C wang q q Liu S J zhang R z Yu z Deng X H zhu C q Jin College of Materials Science & Engineering Sichuan University Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences School of Physics University of Chinese Academy of Sciences Collaborative Innovation Center of quantum Matter

Chemical pressure induced by iso-valent doping has been widely employed to tune physical properties of materials. In this work, we report effects of chemical pressure by substitution of Sb or P into As on a recently discovered diluted magnetic semiconductor(Ba,K)(zn,Mn)_2 As_2, which has the record of reliable Curie temperature of 230 K due to independent charge and spin doping. Sb and P are substituted into As-site to produce negative and positive chemical pressures, respectively.X-ray diffraction results demonstrate the successful chemical solution of dopants. Magnetic properties of both K-underdoped and K-optimal-doped samples are effectively tuned by Sb-and P-doping. The Hall effect measurements do not show decrease in carrier concentrations upon Sb-and P-doping. Impressively, magnetoresistance is significantly improved from7% to 27% by only 10% P-doping, successfully extending potential application of(Ba,K)(zn,Mn)_2 As_2.

关键词： chemical pressure (Ba,K)(zn,Mn)2As2 diluted magnetic semiconductor iso-valent doping

Research on Service Life Prediction Model of Concrete Structure of Sea-crossing Bridge

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武汉理工大学学报 2010年第17期32卷 141-146页

作者： waNg C J zHANg g z LIU K X TU L q LI J H qIN M q zhejiang Province zhoushan Island Linking Construction Commanding Department Zhejiang 316032China Wuhan Harbor Engineering Design & Research Institute Co. Ltd Wuhan 430071China Key Lab of Large-span Bridge Construction Technology Ministry of CommunicationWuhan 430071China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

According to the chloride corrosion environment,service life prediction model of concrete structure of sea-crossing bridge was built using modified Fick's second law and the whole probability calculation method,which was suitable for China. Furthermore,a visual service life prediction program of concrete structure was developed by optimized Monte Carlo method. Meanwhile,Life 365 program was compared,indicating reliability of the prediction program. Finally,the validity of prediction model was verified in JinTang Bridge of zhoushan Island Mainland Linkage Project.

关键词： sea-crossing bridge concrete structure service life prediction model verify

Oxygen and Nitrogen Effects on MC Carbide in K465 Nickel-Base Superalloy

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稀有金属材料与工程 2009年第A3期38卷 13-16页

作者： wang L N zheng q Sun X F guan H R Hu z q Institute of Metals Research Chinese Academy of Sciences Shenyang 110015 China

Effects of oxygen and nitrogen on MC carbide in nickel-base superalloy K465 were investigated, because neither of the two gas elements was found to decide MC carbide morphology monotonically. The morphology of MC carbide under alloy solidified in conventional investment casting condition was observed to transform from script-type to block-type with the total oxygen and nitrogen content (gas content) in samples rising up from 1.2×10-6 mol/g to 2.6×10-6 mol/g. The area fraction and composition of the MC carbide also varied with increase of gas content. However, the morphology of MC carbide kept to be script-type even when gas content was up to 3.4×10-6 mol/g in samples solidified with a much higher cooling rate. These results indicate that effects of gas content on formation of MC carbide can be observed in specimens solidified with low cooling rate, but such changes in MC carbide cannot be found when the cooling rate is high.

关键词：氧碳化物氮含量物理性能碳化物

Microstructural Evolution and Service Performance of Cold-drawn Pure Aluminum Conductor Wires

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Journal of Materials Science & Technology 2017年第9期33卷 1039-1043页

作者： X.M.Luo z.M.Song M.L.Li q.wang g.P.zhang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

Microstructures and service performance(mechanical and electrical properties) of the commercially pure Al conductor wires subjected to different cold drawing strains were investigated. The results show that the microstructures of the cold-drawn Al wires along the radial direction were inhomogeneous, i.e. the texture in the center region was strong and weak components, while that in the surface region shifted from the initial cubic texture to a component and finally developed into a strong component. The volume fraction of the high angle grain boundaries in the surface region was higher than that in the center region. The cold-drawing process greatly enhanced the yield strength of the pure Al wires while retained the acceptable electrical resistivity. The strengthening mechanism and the variation of electrical conductivity of the cold-drawn Al wires are discussed through correlating with microstructure evolution.

关键词： Cold drawing Aluminum Microstructure Strength Conductivity

Using Inverter-Based Renewable generators to Improve the grid Power quality-A Review

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Chinese Journal of Electrical Engineering 2018年第4期4卷 16-25页

作者： Tao wang Heng Nian z.q.zhu Department of Electronic and Electrical Engineering University of SheffieldSheffieldS13JDU.K. College of Electrical Engineering Zhejiang UniversityHangzhou 310027China

With the increasing penetration of renewable power in the grid,renewable generators are expected to play more important roles rather than merely working as active power *** the high controllability and considerable idle capacity of the inverter-based renewable generators,various auxiliary functions for them have been studied to benefit the *** these auxiliary functions,the grid power quality improvement is very *** paper presents a review of the emerging control strategies for inverter-based renewable generators to improve grid power *** related papers are classified with different power quality issues and technical routes,and a comprehensive comparison is *** future trends of this research area are also discussed.

关键词： Renewable generator auxiliary function power quality improvement grid voltage harmonic and unbalance

Magnetic and Electrical Behavior of MnTe_(1-x)Sb_x Alloys

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Journal of Materials Science & Technology 2011年第1期27卷 64-68页

作者： X.He Y.q.zhang z.D.zhang Shenyang National Laboratory for Materials Science Institute of Metal Researchand International Center for Materials PhysicsChinese Academy of SciencesShenyang 110016China

The structure,specific heat,magnetic and electrical properties of MnTe1-xSbx（x=0,0.1,0.15,0.2 and 0.25） alloys have been *** MnTe1-xSbx alloys crystallize in a hexagonal NiAs-type structure,and the impurity of MnSb phase appears when x≥*** MnTe0.9Sb0.1 compound exhibits ferrimagnetic behavior with hysteresis loops even at 350 K,showing that the magnetic properties of MnTe compound are very sensitive to little compositional *** ferromagnetism in the MnTe1-xSbx alloys with higher Sb contents may be attributed to the impurity of MnSb *** dispersive X-ray spectroscopy analysis on the MnTe0.9Sb0.1 compound indicates that Sb is very difficult to dope into the lattice of *** the anomaly of resistivity at 300 K of MnTe0.9Sb0.1 and the peak of specific heat around 304 K of all the alloys are thought to be related with the antiferromagnetic interactions of MnTe-based lattice.

关键词： Electronic transport property Hysteresis loop Specific heat

Analysis of vibration reduction level in an 8/6 switched reluctance machine by active vibration cancellation

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Journal of zhejiang University-Science C(Computers and Electronics) 2010年第10期11卷 808-816页

作者： Xu LIU zai-ping PAN z. q. zHU School of Electrical Engineering Zhejiang University Hangzhou 310027 China Department of Electronic and Electrwal Engmeermg University of Sheffield Sheffield S1 3JD UK

This paper proposes an analytical model for predicting the maximum vibration reduction level in a four-phase 8/6 switched reluctance machine(SRM) by employing active vibration cancellation(AVC),one of the most effective and convenient methods for reducing the vibration and acoustic noise produced by *** on the proposed method,the factors that influence the vibration reduction level are analyzed in *** relationships between vibration and noise reduction levels at resonance frequency and rotor speed are ***,it is shown that a large damping factor will lead to smaller vibration reduction level with AVC while,in contrast,a large resonance frequency will increase the vibration reduction *** finite element analyses and experiments were carried out on a prototype 8/6 SRM to validate the proposed method.

关键词： Active vibration cancellation Analytical model Switched reluctance machine Vibration

Surface modification of tungsten oxide by oxygen vacancies for hydrogen adsorption

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Journal of Materials Science & Technology 2022年第22期117卷 23-35页

作者： q.zhang F.W.Tang z.zhao z.R.Nie X.Y.Song Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

A model for describing the adsorption process of hydrogen on surface of tungsten oxide was proposed based on the first-principle calculations. Multiple factors such as type of active surface, adsorption site and distribution of oxygen vacancies were considered to evaluate the hydrogen adsorption capability of tungsten oxide. The adsorption gibbs free energies, electronic structures and bonding characteristics under various conditions were examined to reveal the influence of oxygen vacancies on the surface. It is found that the capability of hydrogen adsorption of tungsten oxide can be significantly enhanced by adjusting the oxygen vacancy on the outermost layer of certain active surfaces. The modeling predicts that the surface structure stability and gas adsorption ability of tungsten oxide can be simultaneously improved through the formation of W–H bonds. The proposed strategy for moderating surface provides a new approach to obtain excellent gas-sensitive metal oxide materials.

关键词： Metal oxide gas-sensitive material Surface adsorption Oxygen vacancy First-principles calculation