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International Journal of Minerals,Metallurgy and materials 2000年第2期14卷 107-109页

作者： Nan chen Weimin Mao(material science and engineering School, University of science and Technol0gy Beijing, Beijing 100083 China)(department of materials science and engineering, University of Petroleum, Beijing 102200, China) material science and engineering School University of Science and Technology Beijing Beijing 100083 China department of materials science and engineering University of Petroleum Beijing 102200 China

Textures in different layers of superconductors based on YBCO system are analyzed using the methods of pole figure and con-ventional φ scans. It is shown that the φ scanning technology has only 1-dimensional description and could omit some information of3-dimensional orientaion distribution, which will influence the superconductor quality The pole figure method, in contrast, demonstra-tes the orientation distribution 2-dimensionally and gives a comprehensive view of thin filIn textUr, which is a much bettCr method fortexture analysis in superconducting films, in which there is commonly an unique high sharpness textur component.

关键词： superconductor thin film texture YBCO pole figure

New useful special function in quantum optics theory

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Chinese Physics B 2016年第8期25卷 26-29页

作者：陈锋范洪义 department of Mathematics and Physics Hefei University department of material science and engineering University of Science and Technology of China

By virtue of the operator Hermite polynomial method [Fan H Y and Zhan D H 2014 Chin. Phys. B 23 060301] we find a new special function which is useful in quantum optics theory, whose expansion involves both power-series and Hermite polynomials, i.e.,min（m,n）∑l=0^min（m,n）n!m!（-1）^l/l!（n-1）!（m-l）!/Hn-l（x）y^m-l≡ n,m（x,y）.By virtue of the operator Hermite polynomial method and the technique of integration within ordered product of operators（IWOP） we derive its generating function. The circumstance in which this new special function appears and is applicable is considered.

关键词： Hermite polynomial excitation state IWOP method new special function generating function,operator Hermite polynomial method

THE RELATIONSHIP BETWEEN PITTING SUSCEPTIBILITY AND INCLUSIONS IN CARBON STEELS IN ARTIFICIAL SEAWATER

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Acta Metallurgica Sinica(English Letters) 2001年第3期14卷 157-162页

作者： XD. Kong, X.Q. chen, W.S. Chang, D.B. chen and J.X. Zheng (department of material science and engineering, Huazhong University of science and Technology, Wuhan 430074, China) (Basic science department, Naval University of engineering, Wuhan 430033, China) Dept. of Mat. Sci. and Eng. Huazhong Univ. of Sci. and Technol. Wuhan 430033 China

The pittings of five carbon steels have been studied by using anodic polarization test and microscope observation. The results show that pitting susceptibilities are related to the types and shapes of inclusions which are the sites of pitting initiation. The pitting initiating at inclusion needs a potential which is defined as pitting potential and the pitting potential is determined by the type and shape of inclusion. The influence of oxygen content in steel on pitting potential is also discussed.

关键词： carbon steel pitting susceptibility pitting potential inclusion

Mn-doped LiFePO_(4)@C as a high-performance cathode material for lithium-ion batteries

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Particuology 2024年第7期90卷 418-428页

作者： Wenjing chen Fangxiang Song Yumei Yang Qianlin chen School of Chemistry and Chemical engineering Guizhou UniversityGuiyang550025China Collaborative Innovation Center of Guizhou Province for Efficient Utilization of Phosphorus and Fluorine Resources Guizhou UniversityGuiyang550025China

In this work,LiFe_(1-x)MnxPO_(4)@C(x=0,0.01,0.02,0.03)cathode materials were obtained by a simple co-precipitation method and heat treatment,and the influence of Mn-doped modification on the electrochemical performance of LiFePO_(4)@C cathode materials was *** show that by doping an appropriate amount of Mn,the cell volume became larger,and the electronic conductivity increased,which improved the Li+diffusion rate and thus its rate capability and cycle performance of Li-ion *** them,LiFe_(0.98)Mn_(0.02)PO_(4)@C showed superior lithium storage capability;the discharge capacity can reach 150.7 mAh g^(−1)at 0.1 *** cell could discharge up to 155.9 mAh g^(−1)at 1 C under high temperature at 45°C,which was higher than LiFePO_(4)@C(142 mAh g^(−1))under the same test *** discharge capacity of 1 C at room temperature was 139.9 mAh g^(−1),and the cycle stability was 95.9%after 200 *** showed that it had good rate capability and excellent cycle *** results indicate that Mn-doped LFP is a simple and effective strategy for developing high-performance cathode materials.

关键词： Mn-doped LiFePO_(4) Lithium-ion battery High temperature

New 3-mode bosonic operator realization of SU(2) Lie algebra:From the point of view of squeezing

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Chinese Physics B 2014年第9期23卷 62-64页

作者：笪诚陈千帆范洪义 department of material science and engineering University of Science and Technology of China

We consider the quantum mechanical SU（2） transformation e^2λJzJ±e^-2λJz = e^±2λJ±as if the meaning of squeezing with e^±2λ being squeezing parameter. By studying SU（2） operators （J±, Jz） from the point of view of squeezing we find that （J±,Jz） can also be realized in terms of 3-mode bosonic operators. Employing this realization, we find the natural representation （the eigenvectors of J＋ or J-） of the 3-mode squeezing operator e^2λJz. The idea of considering quantum SU（2） transformation as if squeezing is liable for us to obtain the new bosonic operator realization of SU（2） and new squeezing operators.

关键词： quantum mechanical SU(2) transformation 3-mode squeezing operator new 3-mode bosonic op-erator realization of SU(2) Lie algebra

Polyolefin vitrimers bearing acetoacetate functionality

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science China Chemistry 2024年第11期67卷 3861-3867页

作者： Zihao Wang Yue Liu Wenmin Pang Ao chen Min chen Chinese Academy of sciences (CAS) Key Laboratory of Soft Matter Chemistry Department of Polymer Science and Engineering University of Science and Technology of China Institutes of Physical science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education Anhui University

Polyolefin vitrimers are polymer networks bearing reversible covalent crosslinking points, enabling them to be reprocessed and recycled. In this contribution, a series of polyolefin vitrimers were designed based on the acetoacetate-functionalized polyolefin copolymers, which were produced through the direct copolymerization of ethylene with polar comonomers using a phosphinesulfonate palladium catalyst. The pendant acetoacetate group could mediate several characteristic reactions, such as the Michael addition reaction, ketone-amine condensation and metal coordination reaction. As such, structurally adjustable polyolefin vitrimers can be accessed by introducing various dynamic crosslinking bonds, including disulfide exchange, transamination of vinylogous urethane and labile metal coordination bond. The utilization of different crosslinking reactions and the mole ratio of crosslinkers significantly impact the material properties of the resultant polymers. Specifically, the generated polyolefin vitrimers demonstrated excellent reprocessability and closed-loop recycling properties. The study in this work provides an efficient strategy to access various polyolefin vitrimers.

关键词： polyolefin vitrimers acetoacetate group polar monomer olefin copolymerization

A Subdivision-Based Combined Shape and Topology Optimization in Acoustics

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Computer Modeling in engineering & sciences 2024年第4期139卷 847-872页

作者： Chuang Lu Leilei chen Jinling Luo Haibo chen CAS Key Laboratory of Mechanical Behavior and Design of materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei230027China College of Intelligent Construction Wuchang University of TechnologyWuhan430223China Henan International Joint Laboratory of Structural Mechanics and Computational Simulation School of Architecture and EngineeringHuanghuai UniversityZhumadian463000China Beijing Aerospace Technology Institute Beijing100074China

We propose a combined shape and topology optimization approach in this research for 3D acoustics by using the isogeometric boundary element method with subdivision *** existing structural optimization methods mainly contain shape and topology schemes,with the former changing the surface geometric profile of the structure and the latter changing thematerial distribution topology or hole topology of the *** the present acoustic performance optimization,the coordinates of the control points in the subdivision surfaces fine mesh are selected as the shape design parameters of the structure,the artificial density of the sound absorbing material covered on the structure surface is set as the topology design parameter,and the combined topology and shape optimization approach is established through the sound field analysis of the subdivision surfaces boundary element method as a *** topology and shape sensitivities of the approach are calculated using the adjoint variable method,which ensures the efficiency of the *** geometric jaggedness and material distribution discontinuities that appear in the optimization process are overcome to a certain degree by the multiresolution method and solid isotropic material with *** examples are given to validate the effectiveness of the presented optimization approach.

关键词： Subdivision surfaces boundary element method topology optimization shape optimization combined optimization

Recent progress in polymer/layered double hydroxide nanocomposites

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Progress in Natural science:materials International 2006年第6期16卷 573-579页

作者： DING Peng, chen Wei and QU Baojun (State Key Laboratory of Fire science and department of Polymer science and engineering, University of science and Technology of China, Hefei 230026, China) [a] State Key Laboratory of Fire science and department of Polymer engineering University of Science and Technology of china Hefei China

New developments in the studies of nanocomposites based on polymer matrixes and layered double hydroxides (LDHs) in recent years are reviewed combining our relative research work, among which the synthesis techniques, the physicochemical characterizations, and the improved material properties are especially discussed. The possible application of polymer/LDH nanocomposites is also proposed.

关键词： nanocomposite layered double hydroxide synthesis characterization structure property.

A nitric oxide-triggered hydrolysis reaction to construct controlled self-assemblies with complex topologies

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science China Chemistry 2024年第4期67卷 1289-1299页

作者： Wenzhuo chen Yuping Tang Shuai chen Zipei chen Jia He Hongbin Huo Juan Zhang Jiajia Li Fei Yan Wei Tian Laboratory of Shaanxi Administration of Traditional Chinese Medicine for TCM Compatibility Shaanxi Key Laboratory of Chinese Medicine Fundamentals and New Drugs ResearchCollege of PharmacyShaanxi University of Chinese MedicineXianyang 712046China Shaanxi Key Laboratory of Macromolecular science and Technology Xi’an Key Laboratory of Hybrid Luminescent Materials and Photonic DeviceMOE Key Laboratory of Material Physics and Chemistry under Extraordinary ConditionsSchool of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China department of Polymeric materials School of Materials Science and EngineeringTongji UniversityShanghai 201804China

Hydrolysis reactions are capable of directing the non-equilibrium assembly of biomolecular scaffolds to realize sophisticated structures and functions in natural ***,utilizing the proper hydrolysis reactions to construct controlled assemblies with complex topologies is still an arduous challenge in artificial systems and needs to be ***,we report a nitric oxide(NO)-triggered slow hydrolysis strategy for the controlled construction of biomimetic supramolecular toroids(STs),thus realizing their visualization of intermediate structures and regulation of geometry *** presented protocol harnesses hydrolysis reactions to control of non-equilibrium self-assembly processes for the construction of self-assemblies with complex topologies successfully,which sheds light on how the hydrolysis reaction rate can modulate the kinetic pathway of assembly,thus realizing the artificial establishment of bio-inspired hierarchical structures.

关键词： supramolecular toroids controlled self-assembly nitic oxide-triggered hydrolysis pathway regulation