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Anisotropic NdFeB Magnet Fabricated by Single Stroke Hot Deformation

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Journal of Materials Science & Technology 2000年第2期16卷 129-130页

作者： y.Li (Chungnam National University, Taejon, Korea) y.B.kim (Korea Research Institute of Standards and Science, Taejon, Korea) M.J.kim, M.S.Song, J.H.yang, T.K.kim and C.O.kim (Chungnam National University, Taejon, Korea) Chungnam National University Taejon South Korea Korea Research Institute of Standards and Science Taejon South Korea

The general hot deformation process consists of two steps, hot pressing and die-upsetting in order to obtain the anisotropic NdFeB magnet. This is the first report that the high anisotropy NdFeB magnets can be fabricated by single stroke hot deforming the isotropic magnet. The magnetic properties of those materials are: coercivity iHc ～11 kOe, remanence Br ～12 kG, and the maximum energy product (BH)max ～28 ***.

关键词： NdFeB Anisotropic NdFeB Magnet Fabricated by Single Stroke Hot Deformation

Evaluation of spermatogenesis and fertility in F1 male rats after in utero and neonatal exposure to extremely low frequency electromagnetic fields

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Asian Journal of Andrology 2005年第2期7卷 189-194,页

作者： M.K.Chung S.J.Lee y.B.kim S.C.Park D.H.Shin S.H.kim J.C.kim Reproductive Toxicology Division Korea Institute of ToxicologyKorea Research Institute of Chemical TechnologyDaejeon 305-600Korea College of Veterinary Medicine Chungbuk National UniversityCheongju 361-763Korea College of Veterinary Medicine Kyungpook National UniversityDaegu 702-701Korea College of Veterinary Medicine Chonnam National UniversityGwangju 500-757Korea

Aim:To determine whether in utero and neonatal exposure to a 60 Hz extremely low frequency electromagnetic field (EMF) results in spermatotoxicity and reproductive dysfunction in the F1 offspring of ***:Age-matched, pregnant Sprague-Dawley rats were exposed continuously (21 h/day) to a 60 Hz EMF at field strengths of 0 (sham control),5,83.3 or 500 μT from day 6 of gestation through to day 21 of *** experimentally generated magnetic field was monitored continuously (uninterrupted monitoring over the period of the study) throughout the ***:No exposure-related changes were found in exposed or sham-exposed animals with respect to the anogenital distance,preputial separation,testis weight,testicular histology,sperm count,daily sperm production, sperm motility,sperm morphology and reproductive capacity of F1 ***:Exposure of Sprague- Dawley rats to a 60 Hz EMF at field strengths of up to 500 μT from day 6 of gestation to day 21 of lactation did not produce any detectable alterations in offspring spermatogenesis and fertility.

关键词： spermatogenesis electromagnetic fields prenatal exposure postnatal exposure rat

Tooth regeneration: a revolution in stomatology and evolution in regenerative medicine

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International Journal of Oral Science 2011年第3期3卷 107-116页

作者： Sibel yildirim Susan y. Fu Keith kim Hong Zhou Chang Hun Lee Ang Li Sahng Gyoon kim Shuang Wang Jeremy J. Mao Tissue Engineering and Regenerative Medicine Laboratory （TERML） Center for Craniofacial Regeneration Columbia University Medical Center New York NY 10032 USA Department of Basic Science Xi＇an Jiaotong University School of Stomatology Xi＇ an 710049 China

A tooth is a complex biological organ and consists of multiple tissues including the enamel, dentin, cementum and pulp. Tooth loss is the most common organ failure. Can a tooth be regenerated？ Can adult stem cells be orchestrated to regenerate tooth structures such as the enamel, dentin, cementum and dental pulp, or even an entire tooth？ If not, what are the therapeutically viable sources of stem cells for tooth regeneration？ Do stem cells necessarily need to be taken out of the body, and manipulated ex vivo before they are transplanted for tooth regeneration？ How can regenerated teeth be economically competitive with dental implants？ Would it be possible to make regenerated teeth affordable by a large segment of the population worldwide？ This review article explores existing and visionary approaches that address some of the above-mentioned questions. Tooth regeneration represents a revolution in stomatology as a shift in the paradigm from repair to regeneration： repair is by metal or artificial materials whereas regeneration is by biological restoration. Tooth regeneration is an extension of the concepts in the broad field of regenerative medicine to restore a tissue defect to its original form and function by biological substitutes.

关键词： stem cells bioactive cues biomaterials cell homing dental pulp tooth regeneration growth factors scaffold dental implants pulp regeneration

GAMMA TITANIUM ALUMINIDE ALLOy TECHNOLOGy:STATUS AND FUTURE

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Acta Metallurgica Sinica(English Letters) 1999年第4期12卷 334-339页

作者： y W.kim UES,Inc.,OH, USA

Gam matitanium aluminide ( γ TiAl) alloys are emerging as a revolutionary engineeringmaterialsfor hightemperaturestructuralapplications. Onthebasisoftheinformation avail ablein the public domain, this paper discussesthe historical background,status and future prospect of gam maalloytechnologyintheareasofalloy development/ design,processdevelop ment, and applications.

关键词： JOM USA PA TMS FUTURE GAMMA TITANIUM ALUMINIDE ALLOy TECHNOLOGy

Plasma density measurement and downstream etching of silicon and silicon oxide in Ar/NF3 mixture remote plasma source

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Plasma Science and Technology 2019年第6期21卷 52-57页

作者： H J yEOM D H CHOI y S LEE J H kim D J SEONG S J yOU H C LEE Korea Research Institute of Standards and Science(KRISS) Daejeon 34113 Republic of Korea Department of Physics Chungnam National University Daejeon 34134 Republic of Korea

In this study,plasma density measurements were performed near the plume region of the remote plasma source (RPS) in Ar/NF3 gas mixtures using a microwave cutoff *** measured plasma density is in the range of 1010-1011 cm-3 in the discharge conditions with RPS powers of 2-4 kW and gas pressures of 0.87-4 *** plasma density decreased with increasing gas pressures and RPS powers under various Ar/NF3 mixing *** decrease in the plasma density measured at the fixed measurement position (plume region) can be understood by the reduction of the electron energy relaxation length with increases in the gas pressures and mixing ratio of NF3/(Ar/NF3).We also performed downstream etching of silicon and silicon oxide films in this *** etch rate of the silicon films significantly increases while the silicon oxide is slightly etched with the gas pressures and *** was also found that the etch rate strongly depends on the wafer position on the processing chamber electrode,and that the etch selectivity reached 96-131 in the discharge conditions of RF powers (3730-4180 W) and gas pressures (3.6-4 Torr).

关键词： remote plasma source electron density cutoff probe downstream etch

Strain-induced the dark current characteristics in InAs/GaSb type-Ⅱ superlattice for mid-wave detector

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Journal of Semiconductors 2020年第6期41卷 35-38页

作者： H.J.Lee S.y.Ko y.H.kim J.Nah i3system Inc.26-32Gajeongbuk-roDaejeon34113Yuseong-guKorea Department of Electrical Engineering Chungnam National UniversityDaejeon34134Yuseong-guKorea

Type-Ⅱsuperlattice(T2SL)materials are the key element for infrared(IR)***,it is well known that the characteristics of the detectors with the T2SL layer are greatly affected by the strain developed during the growth process,which determines the performance of IR ***,great efforts have been made to properly control the strain effect and develop relevant analysis methods to evaluate the strain-induced dark current *** this work,we report the strain-induced dark current characteristics in InAs/GaSb T2SL MWIR *** overall strain of InAs/GaSb T2SL layer was analyzed by both high-resolution X-ray diffraction(HRXRD)and the dark current measured from the absorber layer at the elevated temperatures(≥110 K),where the major leakage current component is originated from the reduced minority carrier lifetime in the absorber *** findings indicate that minority carrier lifetime increases as the tensile strain on the InAs/GaSb T2SL is more compensated by the compressive strain through‘InSb-like’interface,which reduces the dark current density of the ***,tensile strain compensated devices exhibited the dark current density of less than 2×10^-5 A/cm^2 at 120 K,which is more than one order of magnitude lower value compared to that of the device without tensile strain relaxation.

关键词： mid-wave detector InAs/GaSb typeⅡsuper lattice dark current

Simulation of electron behavior in PIG ion source for 9 MeV cyclotron

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Chinese Physics C 2014年第12期38卷 70-76页

作者： X.J.Mu M.Ghergherehchi y.H.yeon J.W.kim J.S.Chai College of Information & communication Engineering School of Electronic and Electrical EngineeringSungkyunkwan University Department of Energy Science Sungkyunkwan University

In this paper, we focus on a PIG source for producing intense H-ions inside a 9 MeV cyclotron. The properties of the PIG ion source were simulated for a variety of electric field distributions and magnetic field strengths using a CST particle studio. After analyzing the secondary electron emission（SEE） as a function of both magnetic and electric field strengths, we found that for the modeled PIG geometry, a magnetic field strength of 0.2 T provided the best results in terms of the number of secondary electrons. Furthermore, at 0.2 T, the number of secondary electrons proved to be greatest regardless of the cathode potential. Also, the modified PIG ion source with quartz insulation tubes was tested in a KIRAMS-13 cyclotron by varying the gas flow rate and arc current, *** capacity of the designed ion source was also demonstrated by producing plasma inside the constructed 9 MeV cyclotron. As a result, the ion source is verified as being capable of producing an intense H-beam and high ion beam current for the desired 9 MeV cyclotron. The simulation results provide experimental constraints for optimizing the strength of the plasma and final ion beam current at a target inside a cyclotron.

关键词： PIG ion source CST particle studio electromagnetic field secondary electron gas flow rate arc

术前影像学结果预测胆道闭锁病人Kasai术后2年自体肝生存率

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国际医学放射学杂志 2024年第3期 373-373页

作者： H.kim S.y.yoo J.H.kim M.J.kim S.Lee T.y.Jeon 吴玉平

摘要目的探讨应用术前影像学指标预测胆道闭锁（BA）病人Kasai术后2年自体肝生存率的可行性。方法回顾性分析2000—2020年接受Kasai手术的190例BA病人，

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通过结合梯度回波和自旋回波对比增强MRI以减少基于深度学习的脑转移瘤检测中的假阳性：多中心诊断队列验证

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国际医学放射学杂志 2024年第4期 495-495页

作者： S.yun J.E.Park N.y.kim S.y.Park H.S.kim 王笑男

摘要目的开发一种结合梯度回波和快速自旋回波的对比增强MRI深度学习（DL）模型（双增强DL）用于检测脑转移瘤（BM），并与神经影像医师以及仅使用梯度回波影像

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