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Rare earth doping effects on superconducting properties of MgB_2:A review

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Journal of Rare Earths 2019年第2期37卷 124-133页

作者： Wenxian Li Jixiang Kang Siwei Fu Yemin Hu Pengfei Hu Mingyuan Zhu Ying Li Institute of materials & laboratory for Microstructures School of Materials Science and Engineering Shanghai University Institute for Sustainable Energy Shanghai University Shanghai Key laboratory of high temperature Superconductors Physics Department Shanghai University

Rare earth(RE) elements and their compounds have been doped into MgB_2 since the discovery of the superconductivity of MgB_2. The doping effects of RE elements and RE compounds are summarized in terms of different doping methods and the accompanying variations in the superconducting transition temperature, upper critical field, irreversibility field, and critical current density(Jc). Conclusions are drawn on the doping mechanisms to demonstrate the possibility of improvement of Jcin the future. REBy phase inclusions are observed in MgB_2 as nano-pinning centers with significant enhancement of Jcin MgB_2 doped with Y, La, Dy, Ho, Nd, etc. Furthermore, some REs with larger magnetic moments will provide more efficient flux pinning centers with larger pinning forces, which is different with the doping effects and mechanism of ferromagnetic transition metals in MgB_2. The co-doping effects of RE with other dopants are also reviewed due to the multiple advantages of different doping mechanisms.

关键词： Rare earth Critical current density(Jc) Flux pinning Doping

Molecule‑Level Multiscale Design of Nonflammable Gel Polymer Electrolyte to Build Stable SEI/CEI for Lithium Metal Battery

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Nano-Micro Letters 2025年第1期17卷 404-423页

作者： Qiqi Sun Zelong Gong Tao Zhang Jiafeng Li Xianli Zhu Ruixiao Zhu Lingxu Wang Leyuan Ma Xuehui Li Miaofa Yuan Zhiwei Zhang Luyuan Zhang Zhao Qian Longwei Yin Rajeev Ahuja Chengxiang Wang Key laboratory for Liquid‑Solid Structural Evolution and Processing of materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJinan 250061People’s Republic of China Condensed Matter Theory Department of Physics and AstronomyUppsala UniversityUppsala 75120Sweden

The risk of flammability is an unavoidable issue for gel polymer electrolytes(GPEs).Usually,flameretardant solvents are necessary to be used,but most of them would react with anode/cathode easily and cause serious interfacial instability,which is a big challenge for design and application of nonflammable ***,a nonflammable GPE(SGPE)is developed by in situ polymerizing trifluoroethyl methacrylate(TFMA)monomers with flame-retardant triethyl phosphate(TEP)solvents and LiTFSI–LiDFOB dual lithium *** is strongly anchored to PTFMA matrix via polarity interaction between-P=O and-CH_(2)CF_(3).It reduces free TEP molecules,which obviously mitigates interfacial reactions,and enhances flame-retardant performance of TEP *** TEP molecules are also inhibited in solvation of Li^(+),leading to anion-dominated solvation sheath,which creates inorganic-rich solid electrolyte interface/cathode electrolyte interface *** coordination structure changes Li^(+)transport from sluggish vehicular to fast structural transport,raising ionic conductivity to 1.03 mS cm^(-1) and transfer number to 0.41 at 30℃.The Li|SGPE|Li cell presents highly reversible Li stripping/plating performance for over 1000 h at 0.1 mA cm^(−2),and 4.2 V LiCoO_(2)|SGPE|Li battery delivers high average specific capacity>120 mAh g^(−1) over 200 *** study paves a new way to make nonflammable GPE that is compatible with Li metal anode.

关键词： Anchoring effect Nonflammable gel electrolyte In situ cross-linked Electrode-electrolyte interface Li metal battery

Oxidation Behavior of Fe-Ni-Co Based Superalloys and Influence of Yttrium Addition

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Journal of materials Science & Technology 2000年第5期16卷 509-513页

作者： Jiansheng WU+, Laming ZHANG, Junbiao ZHOU and Yin XU (Open laboratory for high temperature materials and Testing, School of materials Science and Engineering, Shanghai Jiaotong University, Shanghai 200030, China) Shaowei ZHANG (Beijing Institute of Aerona Open laboratory for high temperature materials and Testing School of Materials Science and Engineering Shanghai Jiaotong University Shanghai 200030 China Beijing Institute of Aeronautical materials Beijing 100095 China

The oxidation behavior of three Fe-Co-Ni based superalloys with different yttrium additions were investigated at 650℃ in air. The oxidation kinetics of the three alloys follows parabolic law initially, then follows linear law. The oxide scale formed on all three alloys consists mainly of Co dissolved Fe3O4 and partly of FeO and Fe2O3, in which Fe3O4 acts as a protective layer. An yttrium addition into the Fe-Co-Ni based superalloys improves their oxidation resistance by reducing the micro-defects in the scales. Thus, the weight gains of the alloys during the oxidation are reduced, and the transition of parabolic law to linear law is postponed. Pegging was observed on the cross section of alloy with 0.08 wt pct yttrium addition after the oxidation.

关键词： Co In Fe Ni

Solidification characteristics of high Nb-containing γ-TiAl-based alloys with different aluminum contents

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Rare Metals 2015年第6期34卷 381-386页

作者： Yi Liu Rui Hu Hong-Chao Kou Jun Wang Tie-Bang Zhang Jin-Shan Li Ji Zhang The State Key laboratory of Solidification Processing School of Materials Science and Engineering Northwestern Polytechnical University Institute of high temperature materials China Iron and Steel Research Institute Group

The effect of A1 content on the microstructure and solidification characteristics of Ti-A1-Nb-V-Cr alloys in as-cast and isothermally treated states was investigated using X-ray diffraction （XRD）, scanning electron microscopy （SEM） equipped with energy dispersive spectroscope （EDS）, and transmission electron microscopy （TEM）. The typical solidification characteristics are due to the joint influence of both the crystal temperature range and the solidification path. The wide crystallization temperature range contributes to obtaining coarse dendrites in the as-cast Ti47A17Nb2.5V1.0Cr （at%） alloy solidifying through the peritectic reaction. The β-solidifying Ti46A17Nb2.5V1.0Cr （at%） alloy with the narrow crystallization temperature range is attributed to the formation of a homogeneous finegrained microstructure. However, the crystallization temperature range of Ti48A17Nb2.5V1.0Cr （at%） alloy is equivalent to that of Ti46A17Nb2.5V1.0Cr alloy, but it is solidified by peritectic reaction, leading to the formation of finer dendrites.

关键词： Titanium aluminide Crystal temperaturerange Peritectic reaction Dendrite morphology Al-equivalent

Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第01期 249-256页

作者： Qing-Yun Fang Chengyihan Gu Yinghan Chen Wencheng Yan Yong Liang Weipeng Li Chengjian Zhu Jie Han Jin Xie State Key laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

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Crack initiation and propagation induced by inclusions in a nickel-base P/M superalloy under fatigue load

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Rare Metals 2005年第3期24卷 298-300页

作者： ZENG Yanping ZHANG Maicang DONG Jianxin ZHANG Lina XIE Xishan high temperature materials Research laboratory University of Science and Technology Beijing Beijing 100083 China School of materials Science and Engineering Tsinghua University Beijing 100084 China

In situ fatigue tests in special designed SEM were conducted to trace the whole process of crack initiation and propagation fill to fracture in mckel-base P/M superalloy seeded inclusions. The experimental results show that non-metallic inclusions can induce crack initiation. When the inclusion size is larger than the critical one, the crack can propagate as the main crack that induces the specimen to fracture. As a result, the LCF life of the specimen decreases.

关键词： nickel-base P/M superalloy inclusion crack initiation and propagation fracture

Atomic scale visualizations of low-angle grain boundary mediated plasticity by coupled dislocation climb and glide in nanoporous gold

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Nano Research 2023年第2期16卷 2622-2629页

作者： Shufen Chu Junnan Jiang Xiaoran Zhao Baode Sun Pan Liu Shanghai Key laboratory of Advanced high-temperature materials and Precision Forming State Key Laboratory of Metal Matrix CompositesSchool of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Grain boundaries(GBs),as a prevalent structural characteristic,play a crucial role in the deformation of nanoporous metals with nanosized grains and ***,the fundamental understanding of GB-mediated deformation is still lacking because the plastic behavior of discrete ligaments involving GBs remains to be ***,we report atomic scale visualizations of coupled GB dislocation climb and glide in nanoporous gold ligaments with low-angle GBs via in situ tensile straining inside a Cs-corrected transmission electron *** zig-zag motion paths of GB dislocations are precisely determined by real-time tracking of the movements of dislocation *** concurrent climb and glide of the dislocation arrays are confined to a narrow GB region,greatly enhancing GB diffusion in the bicrystal *** findings of coupled dislocation climb and glide shine a light on the room-temperature deformation of nanoporous metals and provide a time-dependent atomic-level physical image for GB engineering.

关键词： nanoporous gold dislocation climb dislocation glide low-angle grain boundaries

high temperature deformation behavior and processing map of hot isostatically pressed Ti-47.5Al-2Cr-2Nb-0.2W-0.2B alloy using gas atomization powders

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Journal of Iron and Steel Research International 2017年第4期24卷 435-441页

作者： Ying Bao Dong-ye Yang Na Liu Guo-qing Zhang Zhou Li Fu-yang Cao Jian-fei Sun School of materials Science and Engineering Harbin Institute of Technology School of materials Science and Engineering Harbin University of Science and Technology Science and Technology on Advanced high temperature Structural materials laboratory Beijing Institute of Aeronautical Materials

The hot compressive deformation behavior of hot isostatically pressed Ti-47.5Al-2Cr-2Nb-0.2W-0.2B alloy using gas atomization powders was systematically investigated and the processing map was obtained in the temperature range of 1323-1473 Kand strain rate range of 0.001-0.5s^（-1）.The calculated activation energy in the above variational ranges of temperature and strain rate possesses a low activation energy value of approximately 365.6kJ/mol based on the constitutive relationship models developed with the Arrhenius-type constitutive model respectively considering the strain rate and deformation *** hot working flow behavior during the deformation process was analyzed combined with the microstructural ***,the processing maps during the deformation process were established based on the dynamic material model and Prasad instability criterion under different deformation ***,the optimal hot processing window of this alloy corresponding to the wide temperature range of 1353-1453 Kand the low strain rate of 0.001-0.1s^（-1） was obtained.

关键词： Hot compressive deformation TiAl alloy Constitutive equation Processing map Gas atomization Hot isostatic pressing

Effect of trace Ce and B additions on the microstructure of Nb-3Si-22Ti alloys

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Progress in Natural Science:materials International 2017年第3期27卷 362-368页

作者： Meiling Wu Liwu Jiang Shiyu Qu Fengwei Guo Ming Li Yongwang Kang Yafang Han Science & Technology on Advanced high temperature Structural materials laboratory AECC Beijing Institute of Aeronautical Materials National Center for materials Service Safety University of Science and Technology Beijing

The effects of trace Ce and B additions on the microstructure Nb-22Ti-3Si alloys were *** microstructure of the alloys was observed by scanning electron microscope（SEM）,and their phase compositions were analyzed with X-ray diffraction（XRD） and Electro-Probe micro-analyzer（EPMA）.The distributions of the elements were detected by Spectrum *** interface of the phases in the alloys was investigated by transmission electron microscopy（TEM）.The results indicated that two phases of Nbss and Nb;Si presented in Nb-22Ti-3Si,Nb-22Ti-3Si-0.2Ce and Nb-22Ti-3Si-0.2B *** segregation of Ti at the interface between Nbss and Nb;Si was promoted and the volume fraction of silicides in the alloy increased with the trace B and Ce addition to the Nb-22Ti-3Si alloy *** there was no single and definite orientation relationship between Nb;Si and Nbss in Nb-22Ti-3Si,Nb-22Ti-3Si-0.2Ce and Nb-22Ti-3Si-0.2B *** with the Nb-22Ti-3Si alloy,the Nbss superlattice structure was found in Nb-22Ti-3Si-0.2Ce and Nb-22Ti-3Si-0.2B alloys.

关键词： Nb-3Si-22Ti alloy Nb3Si Ce B Microstructure Phase interface Superlattice