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Journal of Materials Science & Technology 2020年第6期41卷 1-11页

作者： Majid Jafari chan-woo bang Jong-chan Han Kyeong-Min Kim Seon-Hyeong Na chan-Gyung Park Byeong-Joo Lee Department of Materials Science and Engineering POSTECH Pohang 37673 South Korea

Manufacturing temperatures of severely cold-drawn hyper-eutectoid steel wires are sufficiently high to influence the mobility of dislocations and alloy elements,thereby affecting the materials’mechanical ***,we describe the evolution of microstructure and tensile strength of the as-drawn 3.45 GPa steel wire during post-deformation annealing for 30 min at 150-450℃.Annealing at 150℃raised the strength to 3.77 GPa by age-hardening through activation of dislocations pinning by carbon,while further temperature rising up to 450℃caused a severe loss of *** was proved that annealing at 300 and 450℃destabilizes the lamellar microstructure,promoting the formation of carbon-deficient(Fe,Mn,Cr)3 C-type cementite particles with preferentially rounded and partially faceted *** at 450℃yielded the accumulation of Mn and Cr at the ferrite/particle interfaces,and their concentrations at the interfaces were dependent on the interface structure;i.e.,lower concentrations at rounded interfaces(formed through capillarity–driven coarsening of the spheroidized cementite),and higher concentrations at faceted interfaces(that are initially existing in the as-drawn state).Our proof-of-principle observations,supported by thermodynamic calculations and kinetic assessments,provide a pathway for understanding the changes in microstructural and tensile properties during manufacturing of the hyper-eutectoid steel wires.

关键词： Three-dimensional atom probe(3DAP) High resolution transmission electron microscopy(HRTEM) Nano-grained low-carbon steel Annealing Tensile behavior

High-power and long-life supercapacitive performance of hierarchical, 3-D urchin-like W18049 nanostructure electrodes

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Nano Research 2016年第3期9卷 633-643页

作者： Sangbaek Park Hyun-woo Shim chan woo Lee Hee Jo Song Jae-chan Kim Dong-Wan Kim Department of Materials Science and Engineering Seoul National University Seoul 151-744 Republic of Korea School of Civil Environmental and Architectural Engineering Korea University Seou1136-713 Republic of Korea

We report the facile, one-pot synthesis of 3-D urchin-like W18O49 nanostructures （U-WO） via a simple solvothermal approach. An excellent supercapacitive performance was achieved by the U-WO because of its large Brunauer-Emmett- Teller （BET） specific surface area （ca. 123 m2.g-1） and unique morphological and structural features. The U-WO electrodes not only exhibit a high rate-capability with a specific capacitance （Csp） of -235 F·g-1 at a current density of 20 A.g-1, but also superior long-life performance for 1,000 cycles, and even up to 7,000 cycles, showing -176 F·g-1 at a high current density of 40 A.g-1.

关键词： hierarchical structure W18O49 high-power long cycle life supercapacitor

CaCO_3 film synthesis from ladle furnace slag: morphological change, new material properties, and Ca extraction efficiency

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International Journal of Minerals,Metallurgy and Materials 2018年第12期25卷 1447-1456页

作者： Seung-woo Lee Yong-Jae Kim Jun-Hwan bang Soochun Chae Center for carbon mineralization Korea Institute of Geosciences and Mineral Resources Frontier in extreme physics Korea Research Institute of Standards and Science

A rapidly air-cooled ladle furnace slag(RA-LFS), which is a type of steelmaking slag discharged from a steel mill, was used to synthesize CaCO_3 film. The CaCO_3 film with 35 cm^2 of surface area was synthesized under atmospheric conditions, and the surface morphology of the CaCO_3 films was changed by using additives(CaCl_2 and ethylene glycol). Especially, the addition of CaCl_2 changed the surface morphology of CaCO_3 film with pore and induced new material properties, such as water adsorption. The(012) face of CaCO_3 film(calcite) was rapidly decreased by the addition of CaCl_2. The major components of RA-LFS were calcium(type of CaO, 53.9 wt%) and aluminum(type of Al_2 O_3, 37.9 wt%), and the major crystal phases of RA-LFS were C_3 S, C_(12) A_7, and C_3 A. The calcium extraction efficiency of RA-LFS was significantly increased after the CaCO_3 film synthesis. The material properties(hardness and elastic modulus) and the thermal characteristics of the CaCO_3 films were analyzed by nano-indentation and thermogravimetry–differential thermal analysis. The synthesized CaCO_3 films from RA-LFS and Ca(OH)_2(reagent) showed similarities in terms of their material properties and the decomposition temperature.

关键词： carbon dioxide ladle furnace slag carbonation calcium carbonate film calcium efficiency

Sub-2 nm mixed metal oxide for electrochemical reduction of carbon dioxide to carbon monoxide

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Journal of Energy Chemistry 2023年第9期84卷 303-310页

作者： Devina Thasia Wijaya Andi Haryanto Hyun woo Lim Kyoungsuk Jin chan woo Lee Department of Chemistry Kookmin UniversitySeoul 02707Republic of Korea Department of Materials Science and Engineering Seoul National UniversitySeoul 08826Republic of Korea Department of Chemistry Korea UniversitySeoul 02841Republic of Korea

Mixed metal oxide(MMO) represents a critical class of materials that can allow for obtaining a dynamic interface between its components:reduced metal and its metal oxide counterpart during an electrocatalytic ***,a synthetic method utilizing a MOF-derived micro/mesoporous carbon as a template to prepare sub-2 nm MMO catalysts for CO_(2) electro reduction is *** from the zeolite imidazolate framework(ZIF-8),the pyrolyzed derivatives were used to synthesize sub-2 nm Pd-Ni MMO with different *** Ni-rich(Pd_(20)-Ni_(80)/ZC) catalyst exhibits unexpectedly superior performance for CO production with an improved Faradaic efficiency(FE) of 95.3% at the current density of 200 mA cm^(-2) at-0.56 V *** hydrogen electrode(RHE) compared to other Pd-Ni compositions.X-ray photoelectron spectroscopy(XPS) analysis confirms the presence of Ni^(2+) and Pd^(2+) in all compositions,demonstrating the presence of *** functional theory(DFT) calculation reveals that the lower CO binding energy on the surface of the Pd_(20)-Ni_(80) cluster eases CO desorption,thus increasing its *** work provides a general synthetic strategy for MMO electrocatalysts and can pave a new way for screening multimetallic catalysts with a dynamic electrochemical interface.

关键词： Carbon dioxide reduction Mixed metal oxide Nanoalloy Carbon monoxide Metal-organic framework

Recent updates and current issues of sentinel node navigation surgery for early gastric cancer

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Chinese Journal of Cancer Research 2021年第2期33卷 142-149页

作者： Sung Gon Kim bang wool Eom Hong Man Yoon chan Gyoo Kim Myeong-Cherl Kook Young-woo Kim Keun Won Ryu Center for Gastric Cancer Research Institute&HospitalNational Cancer CenterGoyang-si 410-769Republic of Korea

With the increase in the incidence of early gastric cancer(EGC),several endoscopic and laparoscopic approaches,such as endoscopic submucosal dissection and function-preserving gastrectomy,have been accepted as standard *** node navigation surgery(SNNS)is an ideal surgical option for preservation of most parts of the stomach and consequent maintenance of normal gastric function to improve quality of life in patients with *** many previous studies and clinical trials have demonstrated the safety and feasibility of the sentinel node concept in gastric cancer,the clinical application of SNNS is *** issues regarding technical standardization and oncological safety need to be *** several studies to resolve these problems are being actively performed,and SNNS might be an important surgical option in the treatment of gastric cancer in the future.

关键词： Sentinel node navigation surgery function-preserving surgery early gastric cancer SENORITA

In situ infrared, Raman and X-ray spectroscopy for the mechanistic understanding of hydrogen evolution reaction

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Journal of Energy Chemistry 2024年第3期90卷 632-651,I0014页

作者： Andi Haryanto Kyounghoon Jung chan woo Lee Dong-Wan Kim Department of Chemistry Kookmin UniversitySeoul 02707Republic of Korea School of Civil Environmental and Architectural EngineeringKorea UniversitySeoul 02841Republic of Korea

Hydrogen production by water reduction reactions has received considerable attention because hydrogen is considered a clean-energy carrier,key for a sustainable energy *** methods have been widely used to study the reaction mechanism of the hydrogen evolution reaction(HER),but the calculation results need to be supported by experimental results and direct evidence to confirm the mechanistic *** this review,we discuss the fundamental principles of the in situ spectroscopic strategy and a theoretical model for a mechanistic understanding of the *** addition,we investigate recent studies by in situ Fourier transform infrared(FTIR),Raman spectroscopy,and X-ray absorption spectroscopy(XAS) and cover new findings that occur at the catalyst-electrolyte interface during *** spectroscopic strategies provide practical ways to elucidate catalyst phase,reaction intermediate,catalyst-electrolyte interface,intermediate binding energy,metal valency state,and coordination environment during HER.

关键词： Hydrogen evolution reaction Infrared spectroscopy Raman spectroscopy X-ray absorption spectroscopy Reaction mechanism

Current approaches and future directions in the management of pterygium

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International Journal of Ophthalmology(English edition) 2018年第5期11卷 709-711页

作者： Kyoung woo Kim Jae chan Kim Graduate School of Chung-Ang University College of Medicine Department of Ophthalmology College of MedicineChung-Ang University Hospital

Pterygium,a common ocular surface disorder,has a complex pathophysiology that may mimic *** is altered expression of cell cycle/proliferation-related factors in pterygium ***,similar to cancer treatments,the management of pterygium ought to be multifactorial based on the patient’s *** therapeutic methods for pterygium are focused on surgical resection in conjunction with antimetabolite use,in addition tissue graft is usually performed in the context of the avoidance of bare ***,future directions in the management of pterygia will likely focus on genetic *** perspective views the pathogenesis of pterygium,its existing therapies as well as current and future challenges in its treatment.

关键词： pterygium tumor recurrence future directions

Time usage analysis and satisfaction comparison by occupational area according to the sex of single-parent families

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World Journal of Clinical Cases 2023年第21期11卷 5097-5107页

作者： woo-Hyuk Jang Jong-Sik Jang Jin-Hyuk bang Department of Occupational Therapy College of Health ScienceKangwon National UniversitySamcheok-si 25949Gangwon-doSouth Korea

BACKGROUND Single-parent families are burdened with dual roles as parents amidst economic poverty due to the lack of a *** parents also face the complications of time *** To examine the time use of single-parent families by dividing their time into occupational area and explore the differences in time deficiency and life *** In this study,the time usage in the‘2019 time of life survey’data of the National Statistical Office is classified based on the fourth edition of the Occupational Therapy Practice Framework,and the time use and satisfaction of single-parent families classified according to *** the‘2019 time of life survey’of the National Statistical Office,the subjects who selected single-parent families in the‘single parent-parent-grandchild households’item were first *** data of 404 parents from single-parent families were selected *** time usage,time deficiency,and life satisfaction were analyzed by occupational *** The subjects spent the most time resting and sleeping,followed by engaging in instrumental activities of daily living(IADLs),work,and health *** a result of comparing the subjects by sex,it was found that the male subjects spent more time on work than the female subjects,and the female subjects spent more time on IADLs,education and social *** a result of comparing time deficiency and life satisfaction,the male subjects felt that they lacked time compared to the female *** was no significant difference in life *** examining whether single-parent families'time use by occupa tional area affected the time deficiency,it was found that male's working time make them feel they have less time,while female's leisure time makes them feel they have more *** This study made it possible to determine the characteristics of single-parent households’time use and sex ***,it is expected to be used as basic data for measures to s

关键词： Life satisfaction Occupational area Single-parent Time deficiency Time use

Volume Estimation of Small Scale Debris Flows Based on Observations of Topographic changes Using Airborne LiDAR DEMs

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Journal of Mountain Science 2014年第3期11卷 578-591页

作者： Hosung KIM Seung woo LEE chan-Young YUNE Gihong KIM Department of Civil Engineering Gangneung-Wonju National University

This paper describes a geographic information system(GIS)-based method for observing changes in topography caused by the initiation, transport, and deposition of debris flows using highresolution light detection and ranging(LiDAR) digital elevation models(DEMs) obtained before and after the debris flow events. The paper also describes a method for estimating the volume of debris flows using the differences between the LiDAR DEMs. The relative and absolute positioning accuracies of the LiDAR DEMs were evaluated using a real-time precise global navigation satellite system(GNSS) positioning method. In addition, longitudinal and cross-sectional profiles of the study area were constructed to determine the topographic changes caused by the debris flows. The volume of the debris flows was estimated based on the difference between the LiDAR DEMs. The accuracies of the relative and absolute positioning of the two LiDAR DEMs were determined to be ±10 cm and ±11 cm RMSE, respectively, which demonstrates the efficiency of the method for determining topographic changes at an scale equivalent to that of field investigations. Based on the topographic changes, the volume of the debris flows in the study area was estimated to be 3747 m3, which is comparable with the volume estimated based on the data from field investigations.

关键词： Debris flow Topographic change LiDAR DEM Volume estimation Global navigation satellitesystem (GNSS)

Systematic Revision of Trilobites from the Middle Ordovician(Darriwilian) Klimoli Formation of the Zhuozishan Area,Inner Mongolia,China

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Acta Geologica Sinica(English Edition) 2016年第6期90卷 1955-1975页

作者： LEE Seung-Bae LEE Dong-chan woo Jusun ZHANG Xingliang Geology Division Korea Institute of Geoscience and Mineral Resources Department of Earth Science Education Chungbuk National University Division of Polar Earth-System Sciences Korea Polar Research Institute Early Life Institute and State Key Laboratory of Continental Dynamics Department of GeologyNorthwest University

New morphologic information permits systematic revision of trilobites from the Middle Ordovician Klimoli Formation of the Zhuozishan area, Ordos Basin, Inner Mongolia. The new assemblage is composed of 10 species of the Raphiophoridae, Nileidae, Asaphidae, and Telephinidae.？ An asaphid, aff. Mioptychopyge lashachungensis （previously Paraptychopyge lashachungensis） displays an intermediate morphology between the Chinese nobiliasaphine genera Mioptychopyge and Zhenganites. The pygidial doublure is regarded as the most significant character to differentiate Symphysurus klimoliensis （previously Nileus klimoliensis） of the Nileidae from such closely allied taxa as Poronileus. A nileid, cf. Peraspis kujandensis displays typical nileid morphology, unlike the type species, Peraspis lineolata, which might turn out to be an asaphid. Ampyx gongwusuensis sp. nov. of the Raphiophoridae is the first record of the genus in the Zhuozishan area and reveals morphologic details that might be employed to resolve Ampyx taxonomy in China. Morphologic differences between A. gongwusuensis and Abulbaspis ordosensis might represent a case of sexual dimorphism.

关键词： Invertebrate paleontology Trilobita systematics Klimoli Formation Darriwilian Zhuozishan Inner Mongolia