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journal of Magnesium and Alloys 2022年第10期10卷 2901-2917页

作者： H.T.jeong W.j.kim Departmentof Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

Samples of Mg-8.2Gd-3.8Y-1.1Zn-0.4Zr alloy with and without an intragranular lamellae-shaped long period stacking ordered(LPSO)phase were prepared through heat treatment and a series of hot compression tests on these materials were conducted to examine and evaluate the influence of LPSO on the hot compressive deformation behavior and deformation mechanisms at a given alloy *** values of activation energy for plastic flow(Qc)of the solution treated(without LPSO phase)and annealed alloys(with intragranular LPSO phase)were larger than that for pure Mg,indicating that the presence of a high amount of rare earth(RE)elements and LPSO in the Mg matrix significantly increases *** Qcvalue of the annealed alloy was larger than that of the solution treated alloy at all the strain levels(223.3 vs.195.5 k j/mol in average)and the largest difference in Qcbetween the two alloys was recorded at the smallest strain of 0.1 where precipitation of LPSO during deformation was limited in the solution treated *** observations imply that the formation of LPSO phase out of the RE-rich solid solution matrix during deformation increases Qc,but the increment is not so *** of the hot compressive data of the alloys with LPSO phase and the alloys with RE-rich solid solution matrix in literatures indicates the similarity of the effect of the LPSO and RE-rich solid solution matrix phases on Qcand high-temperature strength.

关键词： Magnesium alloys LPSO Deformation mechanism Dynamic recrystallization Activation energy for plastic flow Processing maps

应用剪切波离散成像斜率值预测移植肾急性排异反应

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国际医学放射学杂志 2024年第5期 620-621页

作者： T.M.kim H.Ahn j.Y.Cho A.Han S.I .Min j.Ha 郑永利

目的评价剪切波离散成像斜率值预测移植肾功能不全的价值。方法回顾性分析2022年11月—2023年2月期间行肾移植的128例受试者资料[中位年龄，55(43～62)

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New para-magnetic(CoFeNi)(50)(CrMo)(50-x)(CB)x(x=20,25,30)non-equiatomic high entropy metallic glasses with wide supercooled liquid region and excellent mechanical properties

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journal of Materials Science & Technology 2020年第8期36卷 135-143页

作者： jeong Tae kim Sung Hwan Hong jin Man Park jürgen Eckert Ki Buem kim Erich Schmid Institute of Materials Science Austrian Academy of Sciences(ÖAW)Jahnstrae 128700LeobenAustria Hybrid Materials Center(HMC) Department of Nanotechnology and Advanced Materials EngineeringSejong University209Neungdong-roGwangjin-guSeoul143-747Republic of Korea Global Technology Center(GTC) Samsung Electronics Co.Ltd129 Samsung-roYeongtong-guSuwonsiGyeonggi-do443-742Republic of Korea Department of Materials Science Chair of Materials PhysicsMontanuniversität LeobenJahnstraße 128700LeobenAustria

In this study,high entropy metallic glasses(HEMGs)were developed through a combination of concepts for designing metallic glasses(main element+transition metal+metalloid element)and high-entropy alloys(more than five elements,each element having an atomic concentration between 5 at.%and 35 at.%).The developed metallic glass alloys are composed of Co-Fe-Ni main elements,transition metals(Cr,Mo)and metalloid elements(C,B).Moreover,the present work reports the thermal,mechanical and magnetic properties of(CoFeNi)(50)(CrMo)(50-x)(CB)x alloys with x=20,25,*** developed as-spun HEMGs exhibit typical paramagnetic properties even for a high amount of ferromagnetic elements(Co,Fe,and Ni)and have high elastic modulus(103–160 GPa)and hardness(14–27 GPa),thus possessing mechanical properties similar to well-known Co-based metallic glasses(Co-Cr-Mo-C-B system).In addition,some of the bulk samples prepared with a diameter of 2 mm form bulk metallic glasses with a high compressive strength around 3.5 *** mechanisms determining the stability of the supercooled liquid,as well as the paramagnetic and mechanical properties for the developed non-equiatomic HEMGs,are discussed.

关键词： Metallic glasses Paramagnetism High entropy alloys Phase stability

Mg-Al Alloys Manufactured by Casting and Hot Working Process

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journal of Materials Science & Technology 2008年第1期24卷 96-98页

作者： j.M.kim j.H.jun W.j.jung Department of Applied Materials Eng. Hanbat National University Daejeon 305-719 Korea Light Materials Team Korea Institute of Industrial Technology Incheon 406-800 Korea

Mechanical properties of Mg-Al based alloys at different fabrication state,namely as-cast,hot rolled,and annealed,were investigated to develop the alloys that are suitable for the casting/hot working ***- imental results indicated that the castability such as hot cracking resistance tends to improve with increasing the aluminum ***,the elongation at elevated temperatures was observed to decrease as the AI content increases,implying difficulties in hot forming.A small amount of Zr additions could significantly enhance the room temperature mechanical properties of hot-rolled Mg-6%Al-1%Zn *** tendency of remarkable grain coarsening at high temperatures was effectively reduced by the Zr *** analyses suggested that very fine Al-3Zr precipitates formed in the Zr-added alloy are responsible for the obtained results.

关键词： Magnesium Casting Forming Tensile properties

Probing the power of central nerve terminals at the level of single vesicles and single transmission events

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Probing the power of central nerve terminals at the level of...

中国神经科学学会第四次会员代表大会暨第七届全国学术会议

作者： Richard W.Tsien N.Charles Harata T Thiagarajan M.Lindskog j.kim Department of Molecular and Cellular Physiology Stanford UniversityStanford CA 94305USA

＜正＞We will present new and as yet unpublished work that provides new insights into signaling at neuronal *** area of research focuses on the existence and functional meaning of multiple modes of synaptic vesicle fusion triggered by Ca～（2+）.The opening of Ca～（2+） channels drives at least two distinct forms of *** the classical mode, known as "full collapse fusion",the vesicle membrane fully merges with and flattens into the presynaptic *** a newly characterized mode,termed "kiss-and-run" the connection between the vesicle interior and the external medium lasts long enough to allow passage of neurotransmitter,but the connection is severed before the identity of the vesicle is *** study the dynamic properties and functional implications of both fusion modes by loading single synaptic vesicles with single photoluminescent reporter particles—quantum *** distinctions between full collapse fusion and kiss-and-run are now in *** same vesicle could undergo K＆R and then FCF,as soon as the next stimulus,10 s *** imaging of the decay of fluorescence associated with a typical K＆R event indicated that the fusion pore was open for well below 1 s and that reacidification proceded rapidly,with a time constant of～1 *** prevalence of K＆R and FCF depends on the stimulus pattern during the processes of Qdot loading and *** of Qdots not only provides a new perspective on intriguing and controversial issues of vesicle dynamics,but also offers the possibility of tracking presynaptic activity within neuronal circuits over extended *** topic concerns the fundamental unit of cell-cell communication between brain neurons:quantal synaptic *** release of a packet of neurotransmitter,for example,glutamate,causes activation of postsynaptic receptors and a brief flow of current that promotes firing of the postsynaptic *** work on neuronal mechanisms that allow synapses to adapt to a sudden or long-la

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来源： cnki会议评论

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应用最小P乘优化技术确定阻尼和自振频率

世界地震工程 1983年第6期 152-158页

作者： Xinsen Lu j.kim Vandiver 杨升田

前言用随机环境中的环境测量结果来估计结构的动力参数对设计资料和性能资料的积累是很重要的,并且已被建议用于结构破坏的检测。因为在大多数情况下实际输入力是很复杂且不易测量,所以在共振频率范围内通常假设输入是一个未知的白噪声... 详细信息

前言用随机环境中的环境测量结果来估计结构的动力参数对设计资料和性能资料的积累是很重要的,并且已被建议用于结构破坏的检测。因为在大多数情况下实际输入力是很复杂且不易测量,所以在共振频率范围内通常假设输入是一个未知的白噪声。这样,在

关键词：动力减振器阻尼比特征频率反应谱振型动力消振器单自由度模型振动分析方法半功率带宽法阻尼固有频率自振频率优化技术

用于诊断肝细胞癌的肝脏影像报告及数据系统2018版5类：一项最新Meta分析

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国际医学放射学杂志 2024年第3期 373-374页

作者： S.Lee Y.Y.kim j.Shin Y.H.Roh j.Y.Choi V.Chernyak 吴玉平

摘要目的该项更新的Meta分析旨在确定使用肝脏影像报告和数据系统（LI-RADS）2018版本（v2018）的LI-RADS LR-5类对肝细胞癌（HCC）的诊断能力，并通过评估成像方

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The Gas-to-Dust Relation in the Dark Cloud L1523-Observational Evidence for CO Gas Depletion

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Chinese journal of Astronomy and Astrophysics 2008年第6期8卷 686-692页

作者： H.G.kim B.G.kim j.H.jung Korea Astronomy and Space Science Institute 61-1 Hwaam Yuseong Daejeon 305-348 Korea

Correlation between gas and dust column density has been studied for the dark globule L1523. The 13CO（j=1→0） emission is used for tracing the gas, and the IR emissions, for tracing the dust constituent. In order to match the beam resolution between the images, a beam de-convolution algorithm based on the Maximum Correlation Method （MCM） was applied on the Infrared Astronomical Satellite （IRAS） data. The morphology of 13CO column density map shows a close correlation to that of 100μm dust optical depth. The distribution of the optical depth at 100 μm follows that of gas column density more closely than does the flux map at either 60 or 100μm. The ratio of the 13CO column density to the 100μm optical depth shows a decreasing trend with increasing dust optical depth in the central part, indicating possible molecular gas condensation onto dust particles. The excessive decrease in the CO column density in the envelope may most probably be due to the photo-dissociation of CO molecules.

关键词： ISM: clouds ISM: dust ISM: molecules

Mending the broken in amyotrophic lateral sclerosis: DNA damage and repair in motor neuron degeneration

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Neural Regeneration Research 2021年第1期16卷 104-105页

作者： Byung Woo kim Lee j.Martin Department of Pathology Division of Neuropathologythe Pathobiology Graduate Training ProgramJohns Hopkins University School of MedicineBaltimoreMDUSA Department of Neuroscience Johns Hopkins University School of MedicineBaltimoreMDUSA

Amyotrophic lateral sclerosis(ALS)is a fatal neurodegenerative disease that causes paralysis and respiratory failure(Petrov et al.,2017).The driving mechanisms are unknown,and there are no effective treatments(Petrov et al.,2017).Aging and a few gene mutations,a common one being missense mutations in superoxide dismutase-1(SOD1),are risk factors for ALS(Figure 1).The recent Food and Drug Administration approval of edaravone for the treatment of ALS putatively supports a role for oxidative and nitrative stresses in the disease processes(Figure 1A).DNA damage,abnormalities in DNA repair,and other nuclear abnormalities are implicated also in the pathogenesis of human ALS(Bradley and Krasin,1982;kim et al.,2020).

关键词： al. damage degeneration

Magnetic force improvement and parameter optimization for magnetic abrasive polishing of AZ31 magnesium alloy

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中国有色金属学会会刊：英文版 2008年第A01期18卷 369-373页

作者： S.O.kim j.S.KWAK Graduate School of Mechanical Engineering Pukyong National UniversitySouth Korea School of Mechanical Engineering Pukyong National UniversitySouth Korea

The magnetic force acting on workpiece to be machined plays a significantly important role in magnetic abrasive polishing *** in a case of polishing nonferrous materials,the strength of magnetic force is very low and it leads lower polishing *** magnesium alloy that has superior mechanical properties for industrial application such as a lightweight and high specific strength is one of the most famous nonferrous *** improving strategy of the magnetic force for the AZ31 magnesium alloy installed with a permanent magnet was proposed and experimental verification was carried *** the proposed strategy,the effect of process parameters on the surface roughness of the AZ31 magnesium alloy was evaluated by a design of experimental method.

关键词：镁合金物理性能磁力最优化设计磁性