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Effects of Ribbon Thickness on Structure and Soft Magnetic Properties of a High-Cu-Content FeBCuNb nanocrystalline Alloy

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Acta Metallurgica Sinica(English Letters) 2022年第2期35卷 235-242页

作者： Li-Cheng Wu Yan-Hui Li Xing-Jie Jia ai-na he Wei Zhang Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian 116024China Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology CAS Key Laboratory of Magnetic Materials and DevicesNingbo Institute of Materials Technology&EngineeringChinese Academy of SciencesNingbo 315201China

The effects of ribbon thickness(t)on the structure and magnetic properties of a Fe_(82.3)B_(13)Cu_(1.7)Nb_(3) alloy in melt-spun and annealed states have been *** the t from 15 to 23μm changes the structure of the melt-spun ribbons from a single amorphous phase to a composite with denseα-Fe nanograins embedded in the amorphous *** grain size(D_(α-Fe))of theα-Fe near the free surface of the ribbon is about 6.7 nm,and it gradually decreases along the cross section toward the wheel-contacted *** increasing the t to 32μm coarsens the D_(α-Fe) near the free surface to 15.2 nm and aggravates the D_(α-Fe) ramp along the cross *** annealing,the ribbon with t=15μm has relatively largeα-Fe grains with D_(α-Fe)>30 nm,while the thicker ribbons possessing the pre-existing nanograins form a finer nanostructure with D_(α-Fe)he ribbon with t=23μm is better than that of the ribbon with t=32μ*** annealed ribbons with t=23 and 32μm possess superior soft magnetic properties to the ribbon with t=15μ*** ribbon with t=23μm exhibits a high saturation magnetic flux density of 1.68 T,low coercivity of 9.6 A/m,and high effective permeability at 1 kHz of 15,*** ribbon with t=32μm has a slightly larger coercivity due to the lower structural *** formation mechanism of the fine nanostructure for the ribbons with suitable t has been discussed in terms of the competitive growth effect among the pre-existingα-Fe nanograins.

关键词： Fe-based nanocrystalline alloy Microstructure Pre-existingα-Fe nanograin Soft magnetic properties Ribbon thickness

Optimal time for mesenchymal stem cell transplantation in rats with myocardial infarction

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第8期9卷 630-637页

作者： Chen-yang JIANG Chun GUI ai-na he Xin-yang HU Jie CheN Yun JIANG Jian-an WANG Department of Cardiology Sir Run Run Shaw Hospital School of Medicine Zhejiang University Hangzhou 310016 China Department of Cardiology the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China Department of Cardiology the First Affiliated Hospital Zhejiang Chinese Medical University Hangzhou 310006 China

Background:Bone marrow mesenchymal stem cell (MSC) transplantation is a promising strategy in the treatment of myocardial infarction (MI). However, the time for transplanting cells remains controversial. The aim of this study was to find an optimal time point for cell transplantation. Methods: MSCs were isolated and cultured from Sprague-Dawley (SD) rats. MI model was set up in SD rats by permanent ligation of left anterior descending coronary artery. MSCs were directly injected into the infarct border zone at 1 h, 1 week and 2 weeks after MI, respectively. Sham-operated and MI control groups received equal volume of phosphate buffered saline (PBS). At 4 weeks after MI, cardiac function was assessed by echocardiography; vessel density was analyzed on hematoxylin-eosin stained slides by light microscopy; the apoptosis of cardiomyocytes was evaluated by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay; the expressions of proteins were analyzed by Western blot. Results: MSC transplantation improved cardiac function, reduced the apoptosis of cardiomyocytes and increased vessel density. These benefits were more obvious in 1-week group than in 1-h and 2-week groups. There are more obvious in-creases in the ratio of bcl-2/bax and the expression of vascular endothelial growth factor (VEGF) and more obvious decreases in the expression of cleaved-caspase-3 in 1-week group than those in other two groups. Conclusion: MSC transplantation was beneficial for the recovery of cardiac function. MSC transplantation at 1 week post-MI exerted the best effects on increases of cardiac function, anti-apoptosis and angiogenesis.

关键词： Mesenchymal stem cells (MSCs) Transplantation Myocardial infarction (MI) Apoptosis

Asynchronous responses of mechanical and magnetic properties to structure relaxation for FeNbB bulk metallic glass

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Journal of Iron and Steel Research International 2018年第6期25卷 637-643页

作者： Zhi-kai Gao An-ding Wang Ping-bo Chen Cheng-liang Zhao Fu-shan Li ai-na he Chun-tao Chang Xin-min Wang Chain-tsuan Liu School of Materials Science and Engineering ZhengzhouUniversity Zhengzhou 450001 Henan China Key Laboratory of Magnetic Materials and Devices NingboInstitute of Materials Technology and Engineering ChineseAcademy of Sciences Ningbo 315201 Zhejiang China Zhejiang Province Key Laboratory of Magnetic Materials andApplication Technology Ningbo Institute of MaterialsTechnology and Engineering Chinese Academy of SciencesNingbo 315201 Zhejiang China Center for Advanced Structural Materials Department ofMechanical and Biomedical Engineering College of Scienceand Engineering City University of Hong Kong Hong KongChina

Asynchronous responses of mechanical and magnetic properties to structure relaxation for the Fe71Nb6B23 bulk metallic glass were systematically investigated. It is interesting that this ternary alloy can combinedly exhibit outstanding magnetic and mechanical properties, especially good ductility, after optimally annealing in structure relaxation stage for eliminating the internal stress and homogenizing the microstructure. The alloy exhibits low coercive force of 1.6 A/m, high effective permeability of 15 x 10^3, high fracture strength of 4.2 GPa and good plastic strAln of 1.8%. It is also found that responses of mechanical and magnetic properties to structure relaxation are asynchronous. The glass transition and crystallization will greatly deteriorate the magnetic and mechanical properties. here we propose a physical picture and demonstrate that the primary structure factors determining magnetic and mechanical properties are different. This work will bring a promising material for application and a new perspective to study the effect of annealing-induced structure relaxation on mechanical and magnetic properties.

关键词： Bulk metallic glass Annealing Mechanical property Magnetic property Structure relaxation

Global Phase Portraits of Uniform Isochronous Centers System of Degree Six with Polynomial Commutator

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 577-599页

作者： Li-na GUO ai-yong CheN Shuai-feng ZHAO School of Mathematics and Statistics Henan University of Science and TechnologyLuoyang 471023China Department of Mathematics Hunan First Normal UniversityChangsha 410205China School of Mechatronics Engineering Henan University of Science and TechnologyLuoyang 471023China

This paper studies the global phase portraits of uniform isochronous centers system of degree six with polynomial *** systems have the form x=-y+xf(x,y),y=x+yf(x,y),where f(x,y)=a_(1)x+a_(2)xy+a_(3)xy^(2)+a_(4)xy^(3)+a_(5)xy^(4)=xσ(y),and any zero of 1+a_(1)y+a_(2)y^(2)+a_(3)y^(3)+a_(4)y^(4)+a_(5)y^(5),y=y is an invariant straight *** last,all global phase portraits are drawn on the Poincare disk.

关键词： global phase portraits uniform isochronous center polynomial commutator invariant straight lines

The hard X-ray nanoprobe beamline at the SSRF

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Nuclear Science and Techniques 2024年第7期35卷 79-88页

作者： Yan he Hui Jiang Dong-Xu Liang Zhi-Sen Jiang Huai-na Yu Hua Wang Cheng-Wen Mao Jia-nan Xie ai-Guo Li Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China

The hard X-ray nanoprobe beamline BL13U is a phase-Ⅱ beamline project at the Shanghai Synchrotron Radiation *** beamline aims to enable comprehensive experiments at high spatial resolutions ranging from 50 to 10 nm. The X-ray energy range of the beamline, 5–25 keV, can detect most elements in the periodic table. Two operating modes were designed to accommodate the experimental requirements of high-energy resolution or high photon flux, respectively. X-ray nanofluorescence, nanodiffraction, and coherent diffraction imaging are developed as the main experimental techniques for BL13U. This paper describes the beamline optics, end station configurations, experimental methods under development, and preliminary test results. This comprehensive overview aims to provide a clear understanding of the beamline capabilities and potential applications.

关键词： Shanghai synchrotron radiation facility Hard X-ray nanoprobe X-ray nanofocusing

Enhanced degradation of refractory organics in ORR-EO system with a blue TiO_(2)nanotube array modified Ti-based Ni-Sb co-doped SnO_(2)anode

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Chinese Chemical Letters 2024年第8期35卷 391-395页

作者： Yifen he Chao Qu na Ren Dawei Liang Department of Materials Chemistry School of Materials Science&EngineeringBeihang UniversityBeijing 102206China Department of Environmental Science Faculty of Environment&LifeBeijing University of TechnologyBeijing 100124China

Recently,a novel 2-electron oxygen reduction reaction(ORR)based electro-oxidation(EO)system was developed,which utilizes a H_(2)O_(2)generation cathode instead of H_(2)evolution cathode.A Ti-based Ni-Sb co-doped SnO_(2)(Ti/naTO)anode was selected for efficient degradation of refractory organics and O_(3)*** synergistic reaction of O3/H_(2)O_(2)further accelerated the generation of hydroxyl radicals(·OH)in the ORR-EO ***,the catalytic activity and long-term effectiveness of the Ti/naTO anode limited the large-scale application of the ORR-EO *** this study,a blue TiO_(2)nanotube array(blue-TiO_(2)-NTA)inter-layer was introduced into the fabrication process between the Ti substrate and naTO catalyst *** to the Ti/naTO anode,the Ti/blue-TiO_(2)-NTA/naTO anode achieved higher efficiency of organic removal and O_(3)***,the accelerated lifetime of the Ti/blue-TiO_(2)-NTA/naTO anode was increased by 7 times compared to the Ti/naTO *** combined with CNTs-C/PTFE air cathode in ORR-EO system,all anodic oxidation and O_(3)/H_(2)O_(2)processes achieved higher•OH *** 92%of TOC in leachate bio-effluent was effectively eliminated with a relatively low energy cost of 45 kWh/t.

关键词： Electro-oxidation Blue TiO_(2)nanotube array O_(3)/H_(2)O_(2)process Refractory organics Leachate bio-effluent

Numerical analysis of wind effects on aerodynamic characteristics of a ducted fan

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Chinese Journal of Aeronautics 2024年第5期37卷 263-280页

作者： Yiwei LUO Tianfu ai Yuhang he Bin XU Yuping QIAN Yangjun ZHANG State Key Laboratory of Intelligent Green Vehicle and Mobility School of Vehicle and MobilityTsinghua UniversityBeijing 100084China Key Laboratory of Conveyance and Equipment Ministry of Education East China Jiaotong UniversityNanchang 330013China Vehicle Research Center School of Mechanical EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

Ducted fans have been extensively used in Unmanned Aerial Vehicles(UAVs)for a variety of missions because of high efficiency,high safety and low ***,as a kind of typical meteorological condition,brings significant aerodynamic interference to the ducted fan,which seriously threatens flight stability and *** this work,the numerical simulation with the Unsteady Reynolds Averaged navier-Stokes(URANS)method and the sliding mesh technique is performed to evaluate the steady wind *** results show that the wind will lead to serious unsteady effects in the flow field,and the thrust fluctuates at the blade passing frequency of 200 *** the wind speed increases,the rotor thrust increases,the duct thrust decreases,and the total thrust changes *** instability may occur when the wind speed exceeds 8 m/*** the angle of low-speed wind increases,the rotor thrust changes little,the duct thrust increases,and the total thrust *** addition,we figure out that cases with the same crosswind ratio are similar in results,and increasing the rotating speed or fan radius is beneficial to performance improvement in *** findings are essential to the ducted fan design and UAV flight control design for stable and safe operations in wind conditions.

关键词： Unmanned Aerial Vehicle(UAV) Ducted fan Wind effect Thrust fluctuations Computational Fluid Dynamics(CFD)

A Scalable Pillar Layered Metal-Organic Framework for natural Gas Purification

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Chemical Research in Chinese Universities 2024年第4期40卷 675-681页

作者： LU nan LAN Lan GAO Qiang LI na BU Xian-he School of Materials Science and Engineering Nankai UniversityTianjin300350P.R.China State Key Laboratory of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin300071P.R.China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang212003P.R.China

One-step harvest of high-purity methane(CH_(4))from ternary propane/ethane/methane(C_(3)H_(8)/C_(2)H_(6)/CH_(4))mixtures remains a desirable yet challenging goal for natural gas ***,adsorbents either suffer from high capacity and selectivity,or are caught in a dilemma of scalable ***,we demonstrate a scalable pillar layered metal-organic framework Ni-MOF for highly efficient one-step CH_(4)***-MOF exhibits high C_(2)H_(6)and C_(3)H_(8)uptakes of 83.3 and 86.1 cm^(3)/g at 298 K and 100 kPa and remarkable C_(2)H_(6)/CH_(4)(50/50,volume ratio,21.5)and C_(3)H_(8)/CH_(4)(50/50,volume ratio,212.0)***,high C_(2)H_(6)(42.2 cm^(3)/g at 10 kPa)and C_(3)H_(8)(64.7 cm^(3)/g at 5 kPa)capacities in the low-pressure region at 298 K were realized on Ni-MOF,suggesting the strong affinities of Ni-MOF towards C_(2)H_(6)and C_(3)H_(8).Furthermore,the dynamic breakthrough experiments revealed that purifying CH_(4)from natural gas in one-step can be achieved in Ni-MOF with high-purity(>99.8%)and productivity(346.0 cm^(3)/g).Most significantly,the production of Ni-MOF can be scalably synthesized at room temperature,rendering it promising potential for industrial *** combined advantages of exceptional separation performance,scalability,and cycle stability of Ni-MOF pave the way for one-step CH_(4)purification from natural gas.

关键词： Metal-organic framework Adsorption and separation natural gas purification Scale-up synthesis

Carbon allocation in Picea jezoensis:Adaptation strategies of a non-treeline species at its upper elevation limit

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Forest Ecosystems 2024年第3期11卷 347-357页

作者： Renkai Dong na Li Mai-he Li Yu Cong Haibo Du Decai Gao Hong S.he Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun130024China School of natural Resources University of MissouriColumbiaMO65211USA Swiss Federal Institute for Forest Snow and Landscape Research WSL8903BirmensdorfSwitzerland Northeast Institute of Geography and Agricultural Ecology Chinese Academy of SciencesChangchun130102China School of Life Science Hebei UniversityBaoding071002China

Understanding the physiological adaptations of non-treeline trees to environmental stress is important to understand future shifts in species composition and distribution of current treeline *** aim of the present study was to elucidate the mechanisms of the formation of the upper elevation limit of non-treeline tree species,Picea jezoensis,and the carbon allocation strategies of the species on Changbai *** employed the^(13)C in situ pulse labeling technique to trace the distribution of photosynthetically assimilated carbon in Picea jezoensis at different elevational positions(tree species at its upper elevation limit(TSAUE,1,700 m a.s.l.)under treeline ecotone;tree species at a lower elevation position(TSALE,1,400 m a.s.l.).We analyzed^(13)C and the non-structural carbohydrate(NSC)concentrations in various tissues following *** findings revealed a significant shift in carbon allocation in TSAUE compared to *** was a pronounced increase inδ^(13)C allocation to belowground components(roots,soil,soil respiration)in TSAUE compared to ***,the C flow rate within the plant-soil-atmosphere system was faster,and the C residence time in the plant was shorter in *** trends indicate enhanced C sink activity in belowground tissues in TSAUE,with newly assimilated C being preferentially directed there,suggesting a more conservative C allocation strategy by *** at higher elevations under harsher *** a strategy,prioritizing C storage in roots,likely aids in withstanding winter cold stress at the expense of aboveground growth during the growing season,leading to reduced growth of TSAUE compared to *** results of the present study shed light on the adaptive mechanisms governing the upper elevation limits of non-treeline trees,and enhances our understanding of how non-treeline species might respond to ongoing climate change.

关键词： ^(13)C pulse labeling Carbon distribution Non-structural carbohydrates(NSC) Non-treeline species Sink activity Stressful environments Upper elevation limit