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Relating atomic local structures and Curie temperature of NdFeB permanent magnets:an X-ray absorption spectroscopic study

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Rare Metals 2018年第11期37卷 983-988页

作者： Mu-Nan Yang Hang Wang Yong-Feng Hu Liu-Yi-Mei Yang Aimee Maclennan Bin Yang institute of Engineering Research Jiangxi University of Scienceand Technology Canadian light source University of Saskatchewan

Relationship between atomic local structures and Curie temperature of NdFeB permanent magnets was investigated semi-quantitatively using synchrotron radiation technique. Fe K-edge X-ray absorption spectroscopy(XAS) was employed to study the local structure of Fe atoms for samples before and after doping Dy, Tb or Gd. It is found that the bond lengths and coordination numbers are changed. Thus, the exchange interaction between Fe atoms increases with Dy, Tb or Gd doping, resulting in the improvement of Curie temperature of NdFeB permanent magnets. The doping effect is proven by experimental measurement of the magnetic properties. Microstructural characterization using scanning electron microscopy(SEM) was also used to further analyze the effect of different rare earth elements doping on Curie temperature of NdFeB permanent magnets.

关键词： Permanent magnet Synchrotron radiation X-ray absorption fine structure Crystal structure Curie temperature

Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni2P for lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第01期 760-769页

作者： Lin Peng Yu Bai Hang Li Meixiu Qu Zhenhua Wang Kening Sun Advanced Research institute of Multidisciplinary Science Beijing Institute of Technology Beijing Key Laboratory of Chemical Power source and Green Catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

Lithium-sulfur （Li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2P by concurrently introducing B-doped atoms and P vacancies in Ni2P （Vp-B-Ni2P）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni2P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides （LiPSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni2P selectively promotes Li2S dissolution and nucleation ***,the Li-S batteries with Vp-B-Ni2P-separators present outstanding rate ability of 777 m A h g-1at 5 C and high areal capacity of 8.03 mA h cm-2under E/S of 5μL mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

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PREPARATION OF TiNi SHAPE MEMORY ALLOY POROSINT BY SHS

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中国有色金属学会会刊:英文版 1997年第4期7卷 85-88页

作者： Chu Chenglin Li Bo Wang Shidong Zhang Shuge Yang Xiaoxi Yin Zhongda Box 433School of Materials Science and EngineeringHarbin institute of Technology ‚Harbin150001 Analysis and Testing CenterSoutheast University ‚Nanjing210018 Research institute of Electric light source MaterialsMinistry of light Industry ‚Nanjing 210015

TiNi shape memory alloy porosint, a promising artificial bone material, was prepared by self propagating high temperature synthesis method. It is found that the key technical parameter affecting the porosity, the shape and distribution of the bores in the synthesized product is the pre heating temperature of green compact. While the pre heating temperature varies between 523 K and 673 K, the TiNi shape memory alloy porosint with wholly homogeneously distributing bores will be gained. The porosity of the porosint is 70% when the pre heating temperature is near 673 K, which is maximal under different pre heating temperatures. The compressive strength of TiNi SMA porosint with a porosity of 70% manufactured by SHS is up to 100 MPa and the percentage recovered is 92%.

关键词： TiNi shape memory alloy porosint self-propagating high-temperature synthesis

Stable stripe and vortex solitons in two-dimensional spin-orbit coupled Bose-Einstein condensates

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Communications in Theoretical Physics 2024年第6期76卷 26-33页

作者： Yuan Guo Muhammad Idrees Ji Lin Hui-jun Li institute of Nonlinear Physics and Department of Physics Zhejiang Normal UniversityJinhua 321004China Zhejiang institute of Photoelectronics and Zhejiang institute for Advanced light source Zhejiang Normal UniversityJinhua 321004China

We present a flexible manipulation and control of solitons via Bose-Einstein *** the presence of Rashba spin-orbit coupling and repulsive interactions within a harmonic potential,our investigation reveals the numerical local solutions within the *** manipulating the strength of repulsive interactions and adjusting spin-orbit coupling while maintaining a zero-frequency rotation,diverse soliton structures emerge within the *** include plane-wave solitons,two distinct types of stripe solitons,and odd petal solitons with both single and double *** stability of these solitons is intricately dependent on the varying strength of spin-orbit ***,stripe solitons can maintain a stable existence within regions characterized by enhanced spin-orbit coupling while petal solitons are unable to sustain a stable existence under similar *** rotational frequency is introduced to the system,solitons undergo a transition from stripe solitons to a vortex array characterized by a sustained *** rotational directions of clockwise and counterclockwise are non-equivalent owing to spin-orbit *** a result,the properties of vortex solitons exhibit significant variation and are capable of maintaining a stable existence in the presence of repulsive interactions.

关键词： Bose-Einstein condensate spin-orbit coupling rotation frequency stripe solitons vortex array

Crystallography of Zr poisoning of Al-Ti-B grain refinement using edge-to-edge matching model

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Journal of Central South University 2013年第10期20卷 2635-2642页

作者：黄元春肖政兵刘宇 School of Mechanical and electrical Engineering Central South University light Alloy Research institute Central South University

The mechanism of zirconium poisoning on the grain-refining efficiency of an Al-Ti-B based grain refiner was studied. The experiment was conducted by melting Al-5Ti-1B and Al-3Zr master alloys together. The edge-to-edge matching model was used to investigate and compare the orientation relationships between the binary intermetallic compounds present in the Al-Ti-B-Zr system. The results show that the poisoning effect probably results from the combination of Al3 Zr with Al3 Ti and the decreased amount of Ti solute, for Al3 Ti particles have good crystallographic relationships with Al3 Zr. Totally six orientation relationships may present between them, while they play vital roles in grain refinement. TiB2 particles appear to remain unchanged because of a bit large misfit. Only one orientation relationship may present between them to prevent Al3 Zr phase from forming on the surface of TiB2, though TiB2 is agglomerated. The theoretical calculation agrees well with the experimental results. The edge-to-edge matching model is proved to be a useful tool for discovering the orientation relationships between phases.

关键词： crystallography Al-Ti-B Zr edge-to-edge matching model poisoning mechanism

Cholesterol-induced deformation of the gramicidin A channel inhibiting potassium ion binding and transport

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Chinese Physics B 2024年第5期33卷 696-702页

作者：肖盼曹宇朱瑾梁清 Center for Statistical and Theoretical Condensed Matter Physics & Department of Physics Zhejiang Normal UniversityJinhua 321004China Zhejiang institute of Photoelectronics & Zhejiang institute for Advanced light source Zhejiang Normal UniversityJinhua 321004China

Gramicidin A(gA)is a kind of antibiotic peptide produced by bacillus brevis and it can dimerize across lipid bilayers to form a monovalent cation *** this work,we investigate the impact of cholesterol in the lipid bilayer on the binding of potassium ions with the gA channel and the transport of the ions across the *** results indicate that cholesterol can significantly influence the conformational stability of the gA channel and cause the channel deformation which inhibits the potassium ion binding with the channel and transport across the *** work provides some molecular insights into understanding of influence of lipids on the activity of gA channel in both model membranes and plasma membranes of intact cells.

关键词： gramicidin A lipid bilayer molecular dynamics interaction

Determination of the calcium species in coal chars by Ca K-edge XANES analysis

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Chinese Physics C 2013年第2期37卷 102-104页

作者：刘利娟刘慧君崔明启胡永峰郑雷赵屹东马陈燕席识博杨栋亮郭志英王杰 institute of High Energy Physics Chinese Academy of Sciences Department of Chemical Engineering for Energy East China University of Science and Technology Canadian light source University of Saskatchewan

Ca-based additives have been widely used as a sulfur adsorbent during coal pyrolysis and gasification. The Ca speciation and evolution during the pyrolysis of coal with Ca additives have attracted great attention. In this paper, Ca species in the coal chars prepared from the pyrolysis of Ca（OH）2 or CaCO3-added coals are studied by using Ca K-edge X-ray absorption near-edge structural spectroscopy. The results demonstrate that Ca（OH）2 , CaSO4 , CaS and CaO coexist in the Ca（OH）2-added chars, while Ca（OH）2 and CaSO4 are the main species in the Ca（OH）2-added chars. Besides, a carboxyl-bound Ca is also formed during both the pyrolysis for the Ca（OH）2-added and the CaCO3-added coals. A detailed discussion about the Ca speciation is given.

关键词： char pyrolysis calcium K-edge XANES

The mechanical performance and a rate-dependent constitutive model for Al3Ti compound

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Defence Technology（防务技术） 2020年第3期16卷 627-634页

作者： Yang Cao Dan-dan Zhang Jian-xiu Liu Kun Liu Jin-guang Du Wen-bin He Jun Ma Henan Key Laboratory of Intelligent Manufacturing of Mechanical Equipment Mechanical and Electrical Engineering InstituteZhengzhou University of Light IndustryZhengzhou450002China

The Al3Ti compound has potential application in the high temperature structure materials due to its low density,high strength and *** mechanical behaviors of the material under different loading rates were studied using compression *** results indicate that Al3Ti is a typical brittle material and its compressive strength is dependent on the strain ***,a series of rate-dependent constitutive equations are needed to describe its mechanical behaviors ***,it is still short of professional research on the material model for *** this study,the mate rial model was developed on the basis of JH-2 constitutive equations using the experimental *** model was then applied in simulating the impact process of Ti/Al3Ti metal-intermetallic laminate composites so as to validate the established *** agreement between simulation and experiment results shows the constitutive model predict the material responses under high rate and large deformation *** work provides more support for the theoretical and numerical research on the intermetallic.

关键词： Titanium aluminide JH-2 model Numerical simulation Quasi-static and dynamic compression tests Ballistic test

Preparation and Easy-Cleaning Property of Rare Earth Composite Ceramic

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Journal of Rare Earths 2006年第z2期24卷 248-250页

作者：王丽娟梁金生李计元梁广川 institute of Power source and Ecomaterials Science Hebei University of Technology

Rare earth and far-infrared mineral composite materials were added to ceramic glazes to prepare easy-cleaning ceramic . The morphology of easy-cleaning ceramic was observed by SEM. The influence of easy-cleaning ceramic on water surface tension and contact angles of water were investigated. Through calculation of ceramic surface free energy and observation of oil drop on ceramic surface in water, the easy-cleaning mechanism of rare earth composite ceramic was studied . It is found that the rare earth composite ceramic can make water surface tension decrease. The surface free energy and the polar component of rare earth composite ceramic are increased. The rare earth composite ceramics have the easy-cleaning property.

关键词： easy-cleaning far infrared surface tension surface free energy polar component rare earths