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Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 192-201页

作者： Shuai li Zhen Ma Jin-Hua Gao School of Science Hebei University of Science and Technology School of Electronics and Information Zhengzhou University of Light Industry School of Physics and Wuhan National High Magnetic Field Center Huazhong University of Science and Technology

We theoretically investigate the spin resolved Friedel oscillation （FO） and quasiparticle interference （QPI） in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r-2in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as *** spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment (***ález-Herrero et al.,Science 352,437 （2016）).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states （FT-LDOS）.Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity

First Principles Study of AI-li Intermetallic Compounds

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Chinese Journal of Chemical Physics 2012年第6期25卷 659-665,I0003页

作者： hai-li Yu Xiao-hui Duan Yong-jun Ma Min Zeng State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials :SouthwestUniversity of Science and Technology Mianyang 621010 China

The structural properties, heats of formation, elastic properties, and electronic structures of four compositions of binary A1-li intermetallics, A13li, A1li, A12li3, and A14li9, are ana- lyzed in detail by using density functional theory. The calculated formation heats indicate a strong chemical interaction between A1 and li for all the A1-li intermetallics. In partic- ular, in the li-rich A1-li compounds, the thermodynamic stability of intermetallics linearly decreases with increasing concentration ***. According to the computational single crystal elastic constants, all the four A1-li intermetallic compounds considered here are mechani- cally stable. The polycrystalline elastic modulus and Poisson＇s ratio have been deduced by using Voigt, Reuss, and Hill approximations, and the calculated ratios of bulk modulus to shear modulus indicate that the four compositions of binary A1-li intermetallics are brittle materials. With the increase of li concentration, the bulk modulus of A1-li intermetallics decreases in a linear manner.

关键词： First principles A1-li intermetallic compound Mechanical property Forma-tion heat Elastic properties

Influence of sintering temperature on the structure and piezoelectric properties of ZnO-modified (li, Na, K)NbO_(3) lead-free ceramics

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International Journal of Minerals,Metallurgy and Materials 2012年第9期19卷 843-848页

作者： hai-tao li Bo-ping Zhang Wei-gang Yang Nan Ma School of Materials Science and Engineering He'nan University of Science and Technology Luoyang 471003 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

ZnO-modified (li, Na, K)NbO3 lead-free ceramics with a nominal composition of li0.06(Na0.535K0.48)0.94NbO3+0.7mol% ZnO (LNKN-ZT) was synthesized normally at 930-1000℃. The Zn ions incorporated into the A-site at a higher sintering temperaVare, which changed LNKN-Z7 to soft piezoelectric ceramics with the mechanical quality factor decreasing from 228 to 192. A phase transition from tetragonal to orthorhombic symmetry was identified by XRD analysis, and the corresponding calculation of lattice parameters was conducted at 970-980℃. Because of such transitional behavior and fine microstructure, the optimized values of piezoelectric coefficient, planar electromechanical coupling coefficient, and relative dielectric constant were obtained.

关键词： piezocemmics niobates zinc oxide modification phase transitions piezoelectricity sintering

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用分时选择离子质谱法一次检测多种药物

刑事技术 2005年第3期30卷 29-30页

作者：刘海燕李长立王可唐军杨洪尚山东省济南市公安局刑警支队 250002 山东省济南市天桥公安分局 250031

目的建立一种能避免生物样品中杂质的干扰,一次排查多种药、毒物,准确、灵敏度高的检验方法。方法应用分时选择离子质谱法,对常见毒物进行检验研究。结果在样品经简单净化处理的情况下,以分时选择离子质谱法检测,一次检测多个毒物(最多3... 详细信息

目的建立一种能避免生物样品中杂质的干扰,一次排查多种药、毒物,准确、灵敏度高的检验方法。方法应用分时选择离子质谱法,对常见毒物进行检验研究。结果在样品经简单净化处理的情况下,以分时选择离子质谱法检测,一次检测多个毒物(最多32个),定性、定量准确,灵敏度50～100ng/ml,经与全扫描质谱法进行比较,灵敏度提高2～3个数量级。结论该方法能有效提高排查毒物检测灵敏度,适用于常见毒物的排查检验。

关键词：质谱法离子分时药物检测灵敏度生物样品检验方法方法应用净化处理毒物排查数量级

Ion thruster accelerator grid erosion mechanism under extreme conditions of cylindrical erosion and chamfer erosion

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Chinese Journal of Aeronautics 2023年第6期36卷 128-139页

作者： Guangqing XIA Jiahui li chang LU hai GENG Vladimir A.SAETCHNIKOV Juan li Yanlong WANG State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDalian University of TechnologyDalian 116024China Key Laboratory of Advanced Technology for Aerospace Vehicles of liaoning Province Dalian University of TechnologyDalian 116024China Collaborative Innovation Center of Micro&Nano Satellites of Hebei Province North China Institute of Aerospace EngineeringLangfang 065000China Science and Technology on Vacuum Technology and Physics Laboratory Lanzhou Institute of PhysicsLanzhou 73000China Physics and Aerospace Technology Department Belarusian State UniversityMinsk 220030Belarus

In this paper,the abnormal experimental phenomenon on barrel erosion under extreme working conditions in the ultra-long life experiment(>10000 h)of ion thruster ion optics is studied by the Immersed-Finite-Element Particle-In-Cell Monte-Carlo-Collision(IFE-PIC-MCC)method and the grid erosion evaluation *** transport process of beam ions and Charge Exchange(CEX)ions in the grid system,and the characteristics and mechanisms of the aperture barrel erosion under extreme erosion conditions(*** cylindrical erosion and chamfer erosion)were systematically *** to the advantage of the IFE method for dealing with complex boundaries in structured mesh,the aperture barrel erosion morphology of the accelerator grid is reconstructed accurately based on the experimental *** results show that,with the evolution of working conditions,the mechanism of the aperture barrel erosion changes significantly,which relies heavily on the accelerator grid *** change of the accelerator grid aperture barrel morphology has a significant effect on the behavior of CEX ions,and only affects the local electric field distribution,but has no effect on the upstream plasma *** the erosion progresses,the erosion position moves downstream along the grid aperture axis direction,and the erosion range becomes *** of the erosion phase,the erosion rate of the CEX ions located downstream of the decelerator grid is the *** erosion rate is related to the mean incident energy and angle,and their variation is closely related to the position and trajectory of CEXions.

关键词： Accelerator grid Charge Exchange(CEX)ions Erosion IFE-PIC-MCC Ion propulsion

Effect of Noncontact Ultrasonic Technology on Solidification Quality of Electroslag Steel

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Journal of Iron and Steel Research International 2016年第11期23卷 1168-1176页

作者： Xiao-fang SHI li-zhong chang Zheng-hai ZHU Jian-jun WANG li ZHOU School of Metallurgy Engineering Anhui University of Technology

A new electroslag furnace with ultrasonic vibration introduced through water-cooled base plate was de- signed and the effects of ultrasonic power on the distribution of elements, compactness and carbides in the electroslag remelting （ESR） ingots was investigated. The results showed that the distribution of elements on the entire excita- tion section changed with the change of ultrasonic power under experimental conditions. The statistical segregation of elements was minimum when the ultrasonic power was 500 W, whereas excessively high or excessively low power was not conducive to the uniform distribution of elements. Meanwhile, the compactness of ESR ingots gradually in- creased with the increase in ultrasonic power and distribution of compactness was the most uniform when ultrasonic power reached 500 W. Further increase in the ultrasonic power was not conducive to the improvement of compactness. The distribution characteristic of carbides was similar to the distribution of elements and compactness. The re- sults indicated that the ultrasonic vibration introduced through water-cooled base plate was advantageous in impro- ving solidification quality. However, this method needed reasonable ultrasonic power. Moreover, the effects of ultra- sonic power varied for different elements.

关键词： ultrasonic eleetroslag remelting solidification element distribution carbide

Sr2+-doped rhombohedral liHf2(PO4)3 solid electrolyte for allsolid-state li-metal battery

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Rare Metals 2020年第9期39卷 1092-1098页

作者： Qing-Hui li chang Xu Bing Huang Xin Yin College of Electrical and Information Engineering Hunan UniversityChangsha 410082China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China School of Materials Science and Engineering Tianjin UniversityTianjin 300072China

Solid-state electrolytes in rechargeable all-solidstate li-metal batteries,which have better safety and higher specific capacity than conventional rechargeable liion batteries with liquid electrolytes,are limited by the low li-ion conductivity of the solid electrolyte and the large electrolyte/electrode interfacial ***,we report a new rhombohedral NAS ICON structure li1.4Sr0.2Hf1.8(PO4)3 with a high li-ion conductivity of 1.62×10-5 S·cm-1 at 25℃,and its conductivity can be improved to 3.4×10-5 S·cm-1 after the densification of the pellet by hot ***1.4Sr0.2Hf1.8(PO4)3 coated by a thin layer of polymer electrolyte showed a stable lowimpedance dendrite-free plating/stripping process in a symmetric li/li cell for 100 h;moreover,the li1.4Sr0.2Hf1.8(PO4)3 electrolyte had a small interfacial resistance in all-solid-state li/liFePO4 cell,which allows a high Coulombic efficiency and good cycling of the cell.

关键词： Solid-state electrolyte NASICON Rhombohedral phase Interfacial resistance All-solid-state battery

Hierarchical microstructure and two-stage corrosion behavior of a high-performance near-eutectic Zn-li alloy

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Journal of Materials Science & Technology 2021年第21期80卷 50-65页

作者： Zhen li Zhang-Zhi Shi hai-Jun Zhang Hua-Fang li Yun Feng Lu-Ning Wang Beijing Advanced Innovation Center for Materials Genome Engineering School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing100083China Department of Interventional and Vascular Surgery The Tenth People's Hospital of ShanghaiTongji UniversityShanghai200072China National United Engineering Laboratory for Biomedical Material Modification Branden Industrial ParkQihe Economic&Development ZoneDezhou CityShandongDezhou251100China Ophthalmology Department Peking University Third HospitalPeking UniversityBeijing100083China

In order to improve mechanical and corrosion properties of biodegradable pure Zn,a knowledge-based microstructure design is performed on Zn-li alloy system composed of hard β-liZn_(4) and soft Zn *** and multi-modal grain structure are designed to toughen β-liZn_(4) while strengthen Zn,resulting in high strength and high ductility for both the ***-like secondary Zn precipitates form in β-liZn4,while fine-scale networks of string-like β-liZn4 precipitates form in Zn with a tri-modal grain *** a result,near-eutectic Zn-0.48 li alloy with an outstanding combination of high strength and high ductility has been fabricated through hot-warm rolling,a novel fabrication process to realize the microstructure *** as-rolled alloy has yield strength(YS) of 246 MPa,the ultimate tensile strength(UTS) of 395 MPa and elongation to failure(EL) of 47 %.Immersion test in simulated body fluid(SBF) for 30 days reveals that li-rich products form preferentially at initial stage,followed by Zn-rich products with prolonged *** insoluble li_(2) CO_(3) forms a protective passivation film on the alloy surface,which suppresses the average corrosion rate from 81.2 μm/year at day one down dramatically to 18.2 μm/year at day ***,the average corrosion rate increases slightly with decrease of li2 CO_(3) content,which undulates around the clinical requirements on corrosion resistance(i.e.,20 μm/year) claimed for biodegradable metal stents.

关键词： Zn alloy Microstructure design Mechanical properties Interfacial structure Corrosion passivation

Microstructural Feature and Evolution of Rapidly Solidified Ni3Al-Based Superalloys

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Acta Metallurgica Sinica(English Letters) 2019年第6期32卷 764-770页

作者： Ye-Fan li Chong li Jing Wu Hui-Jun li Yong-chang liu hai-Peng Wang State Key Lab of Hydraulic Engineering Simulation and Safety School of Materials Science and EngineeringTianjin UniversityTianjin 300354China Department of Applied Physics School of ScienceNorthwestern Polytechnical UniversityXi'an 710129China

The Ni3Al-based superalloy was rapidly solidified in the form of droplets with varying *** cooling rate(Rc)is a function of diameter(D)of *** the decrease in droplet sizes(increase in the cooling rates),the volume fraction ofγ’+γeutectic structure increases from 21.31(D=1400 lm,Rc=3.6 9 102 K s-1)to 36.31%(D=270 lm,Rc-=2.3 9 103 K s-1).Moreover,unimodal size distribution of nano-γ’exists in the droplets instead of bimodal dual-size distributions ofγprecipitates that are normal in as-cast alloys.

关键词： Ni3Al-based superalloy Microstructure Rapid solidification γ’precipitate