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Giant magneto-impedance effect of two paralleled amorphous microwires

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Rare Metals 2016年第4期35卷 344-348页

作者： Shu-Ling Zhang Yue-Sheng Chai da-qing fang Lu-Cai Wang da-Wei Xing Jian-Fei Sun School of Materials Science and Engineering Taiyuan University of Science and Technology School of Materials Science and Engineering Harbin Institute of Technology

Giant magneto-impedance （GMI） is effectively enhanced by the mutual magnetic interaction between two amorphous microwires. A comparative study on GMI properties of a single wire and two wires arranged in par- allel mode was reported in this work. Two-peak （TP） of impedance characteristic is presented when the dc external field changed from 0 to 320 A,m-＇ in two-wire system, which is attributed to successive magnetization process in two wires induced by their magnetic interaction. And the evolution of single peak to TP phenomenon, when the distance between two wires is upto 8 ram, evidences a distance dependence of transformation from successive magnetization to simultaneous via a corresponding dis- tance dependence of magnetostatic interactions. It is pro- posed that the recombination of magnetic interaction and the shielding effect results in a distance dependency of GMI response. When the distance is 8 ram, the magneti- zation process is close to synchronous between two wires, which give rises to higher circular permeability and better GMI response. The impedance ratio AZ/Z increases from 74.5 % of single wire to 172.4 % at 10 MHz. However, when the distance is upto 12 mm, the magnetic interaction is weak and magnetization process is completely independent, and GMI response decreases, relatively. This indicates that the GMI response could be effectively improved in a two-wire connection with an optical distance, which is promising and useful for the application of high-performance GMI sensors.

关键词： Amorphous microwire Magnetic interaction Giant magneto-impedance Magnetization

Degradation research of protective coating on AZ91D Mg alloy components via simulated contamination

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Journal of Magnesium and Alloys 2016年第3期4卷 220-229页

作者： Bao-sheng Liu Ya-fei Kuang Yue-sheng Chai da-qing fang Min-gang Zhang Ying-hui Wei College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuanShanxi 030024China Engineering Research Center for Magnesium Alloys of Shanxi Province Taiyuan University of Science and TechnologyTaiyuanShanxi 030024China College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuanShanxi 030024China

Accelerated environmental(hygrothermal)exposure experiments are performed on organic paints coated on commercial die-cast AZ91D Mg alloys to investigate the effects of contamination on ***,artificial human perspiration spray is used to contaminate the substrate *** occurred only for paints that are spread on surfaces with the perspiration *** blisters gradually form at longer test times,and the volume of blistering *** electron microscopy indicates that blistering is initiated by contamination and/or substrate corrosion at the interface of the organic paints and the *** is characterized for two samples exposed to the hygrothermal environments for various times,and is found to be initially empty in the early *** chloride contaminants from the perspiration lead to in situ adhesion ***,the paints volume expands,and the associated compressive stress causes it to *** long-term test exposure,chloride anions corrode the substrate under the films,and MgO,Mg(OH)_(2),and Mg_(2)(OH)_(3)Cl corrosion products fill the ***,a model of blistering evolution is discussed.

关键词： Mg alloys Organic paints Artificial human perspiration Blistering Corrosion

Effects of solid solution treatment and cooling on morphology of LPSO phase and precipitation hardening behavior of Mg-Dy-Ni alloy

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Transactions of Nonferrous Metals Society of China 2017年第11期27卷 2381-2389页

作者： Li-tao YUAN Guang-li BI Yuan-dong LI Jing JIANG Yu-xiang HAN da-qing fang Ying MA State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals Lanzhou University of Technology Lanzhou 730050 China College of Materials Science and Engineering Taiyuan University of Science and Technology Taiyuan 030024 China

Effects of solid solution treatment and cooling on the morphology of long period stacking order(LPSO)phase and precipitation hardening behavior of Mg?2Dy?0.5Ni(molar fraction,%)alloy were *** of the as-cast alloy mainly consisted ofα-Mg phase,bamboo-like Mg12DyNi phase with LPSO structure distributed between dendrites and small amounts of cubic Dy *** solid solution treatment at565oC for12h and subsequent different cooling conditions,dot-shaped,block,fine lamellar and rod-shaped LPSO phases precipitate in Mg matrix,*** continuous cooling conditions(furnace and air cooling),the fine lamellar LPSO phase generally forms in grain interior and its volume fraction increases and block LPSO phase coarsens with increasing cooling *** discontinuous cooling conditions(air cooling after furnace cooling to415and265°C),the dot-shaped LPSO grows into the rod-shaped phase,which results in an decrease of cooling hardening behavior of alloy.

关键词： Mg.Dy.Ni alloy LPSO phase microstructure precipitation hardening

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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干细胞的趋电性迁移及机制

中国组织工程研究 2025年第23期29卷 4984-4992页

作者：韩芳舒晴贾绍辉田峻武汉体育学院运动医学院湖北省武汉市430079 武汉大学中南医院骨科康复科湖北省武汉市430071

背景:随着对干细胞技术研究的深入,如何使其准确归巢成为临床应用中的一大难题。除药物和趋化因子等信号的诱导外,电场也被广泛应用于指导干细胞的定向迁移,并可增强其迁移速度和定向性。目的:旨在分析总结电场对干细胞迁移特性的影响,... 详细信息

背景:随着对干细胞技术研究的深入,如何使其准确归巢成为临床应用中的一大难题。除药物和趋化因子等信号的诱导外,电场也被广泛应用于指导干细胞的定向迁移,并可增强其迁移速度和定向性。目的:旨在分析总结电场对干细胞迁移特性的影响,同时综述可能的作用机制。方法:通过检索Pub Med和中国知网数据库,收集截至2024年3月的相关文献,英文检索词:“stem cells,direct current electric field,pulsed electric field,migration,electric field device,mechanism”;中文检索词:“干细胞,直流电场,脉冲电场,迁移,电场装置,机制”。排除不能获取全文和与主题无关的文献。结果与结论:根据筛选要求共纳入58篇文献,包括中文文献15篇及英文文献43篇。文献以脂肪间充质干细胞、骨髓间充质干细胞、神经干细胞、表皮干细胞、人胚胎干细胞和人诱导性多功能干细胞为研究对象,在迁移装置中研究电场的不同参数对上述干细胞迁移的影响及其机制。(1)电场作为一种简单、无创且稳定的干预方式在指导干细胞定向迁移的过程中起着积极作用;(2)不同类型的干细胞发生趋电性迁移的方向不同,同时大部分干细胞的迁移速度和定向性是随着电场强度增加而增加的;(3)不同的电场装置在观测干细胞迁移时的侧重点不同,可根据实验目的而择优选择相关装置;(4)不同干细胞趋电性迁移的机制不完全相同,多数干细胞迁移过程中有MAPK通路、ROCK活化以及PI3K功能的参与,同时还有其他蛋白质复合物与信号通路参与调控该过程;(5)除电场参数不同之外,细胞本身的衰老情况和培养环境也会对趋电性迁移的结果产生影响。总而言之,电场作为一种影响干细胞迁移特性的重要信号,与其他新兴材料结合在组织工程应用中展现出了一定的潜力,有望在指导干细胞归巢方面发挥更加重要的作用,促进骨组织再生和修复以及神经系统、自身免疫系统以及肿瘤等疾病的研究取得更大的突破。

关键词：干细胞电场趋电性迁移机制归巢效应物理因子电场装置细胞衰老培养环境

Reaction Processes at the Initial Stage of Diamond Nucleation on the Surface of Si(111)

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Chinese Physics Letters 1998年第12期15卷 910-912页

作者： XIE fang-qing ZHANG qing-zhe LIN Zhang-da State Key Laboratory of Surface Physics Institute of PhysicsChinese Academy of SciencesBeijing 100080

The thermal behavior of CHx(x=2,3)radicals and H atoms adsorbed on Si(111)surface was investigated by high-resolution electron-energy-loss spectroscopy,quadrupole mass spectrometry,and low-energy electron *** on the analysis of thermal desorption mass spectrometry,the initial stage of diamond nucleation on Si is *** with the result reported by Lee for diamond,it is concluded that low stability of hydrocarbon species on Si is the basic reason which results in the difficulty of diamond nucleation on perfect Si surface.

关键词： diffraction. Diamond thermal

Optimal Grouping of Heterogeneous Components in Series and Parallel Systems Under Archimedean Copula Dependence

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Journal of Systems Science & Complexity 2022年第3期35卷 1030-1051页

作者： fang Longxiang ZHANG Xinsheng JIN qing Department of Mathematics and Statistics Anhui Normal UniversityWuhu 241000China Department of Statistics Fudan UniversityShanghai 200433China

This paper considers series and parallel systems comprising n components drawn from a heterogeneous population consisting of m different *** components within each subpopulation are assumed to be dependent,while the subpopulations are independent of each *** authors also assume that the subpopulations have different Archimedean copulas for their *** this setup,the authors discuss the series and parallel systems reliability for three different cases,*** authors use the theory of stochastic orders and majorization to establish the main results,and finally present some numerical examples to illustrate all the results established here.

关键词： Archimedean copula majorization parallel system reliability Schur-convex/concave function series system stochastic orders

Effect of source size and emission time on the p–p momentum correlation function in the two-proton emission process

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Nuclear Science and Techniques 2020年第5期31卷 64-69页

作者： Long Zhou De-qing fang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China

The effect of source size and emission time on the proton-proton(p-p)momentum correlation function(Cpp(q))has been studied *** a spherical Gaussian source with space and time profile according to the function S(r,t)~exp(-r2/2 r02-t/τ)in the correlation function calculation code(CRAB),the results indicate that one Cpp(q)distribution corresponds to a unique combination of source size r0 and emission timeτ.Considering the possible nuclear deformation from a spherical nucleus,an ellipsoidal Gaussian source characterized by the deformation parameter∈=ΔR/R has been *** is almost no difference of Cpp(q)between the results of spherically and ellipsoidally shaped sources with small *** results indicate that a unique source size r0 and emission time could be extracted from the p-p momentum correlation function,which is especially important for identifying the mechanism of twoproton emission from proton-rich ***,considering the possible existence of cluster structures within a nucleus,the double Gaussian source is *** results show that the p-p momentum correlation function for a source with or without cluster structures has large systematical differences with the variance of r0 andτ.This may provide a possible method for experimentally observing the cluster structures in proton-rich nuclei.

关键词： Two-proton emission p–p momentum correlation function Source size Emission time

Controlling Spatiotemporal Chaos Using Nonlinear Feedback Functional Method

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Chinese Physics Letters 1997年第11期14卷 823-826页

作者： fang Jin-qing M.K.Ali fang qing China Institute of Atomic Energy Beijing 102413 Department of Physics The University of LethbridgeLethbridgeAlberta TlK 3M4Canada Beijing Institute of Television Technology Beijing 100031

Nonlinear feedback functional method for controlling spatiotemporal chaos is *** a key point,some typical kinds of nonlinear feedback functions are *** efficiency and robustness of the method based on the flexibility ... 详细信息

关键词： Nonlinear nonlinear Chaos