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Journal of Environmental Sciences 2017年第12期29卷 84-91页

作者： In-Young Chung yu-Mi Park Hyun-Jeoung Lee Hyuk kim dong-Hoon kim Il-Gyu kim Sang-Min kim Young-Sun Do Kwang-Seol Seok Jung-Hwan Kwon Chemical Research Division Environmental Health Research Department National Institute of Environmental ResearchIncheon Division of Environmental Science and Ecological Engineering Korea University

It is thought that there are many unregulated anthropogenic chemicals in the *** risk assessment of chemicals, it is essential to estimate the predicted environmental concentrations. As an effort of identifying residual organic contaminants in air and water in Korea, nontarget screening using two-dimensional gas chromatography time-of-flight mass spectrometry（GC × GC-TOFMS） was conducted at 10 sites using polyurethane foam passive air sampler and at 6 sites using polydimethyl siloxane（PDMS） passive water sampler in three different seasons in 2014. More than 600 chemical peaks were identified satisfying the identification criteria in air and water samples, respectively, providing a list for further investigation. Chemical substances with reported national emission rates in2014（n = 149） were also screened for potential existence in the environment using a level Ⅱ fugacity model. Most of chemical substances classified as not detectable were not identified with detection frequency greater than 20% by nontarget screening, indicating that a simple equilibrium model has a strong potential to be used to exclude chemicals that are not likely to remain in the environment after emissions from targeted monitoring.

关键词： Nontarget screening GC × GC-TOFMS Passive sampling Pollutant release and transfer register(PRTR) Fugacity model

Microstructure and Properties of the Cr–Si–N Coatings Deposited by Combining High-Power Impulse Magnetron Sputtering(HiPIMS) and Pulsed DC Magnetron Sputtering

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Acta Metallurgica Sinica(English Letters) 2017年第7期30卷 688-696页

作者： Tie-Gang Wang yu dong Belachew Abera Gebrekidan Yan-Mei Liu Qi-Xiang Fan Kwang Ho kim Tianjin Key Laboratory of High Speed Cutting and Precision Manufacturing Tianjin University of Technology and Education Global Frontier R&D Center for Hybrid Interface Materials Pusan National University

The Cr–Si–N coatings were prepared by combining system of high-power impulse magnetron sputtering and pulsed DC magnetron sputtering. The Si content in the coating was adjusted by changing the sputtering power of the Si *** virtue of electron-probe microanalysis, X-ray diffraction analysis and scanning electron microscopy, the influence of the Si content on the coating composition, phase constituents, deposition rate, surface morphology and microstructure was investigated systematically. In addition, the change rules of micro-hardness, internal stress, adhesion, friction coefficient and wear rate with increasing Si content were also obtained. In this work, the precipitation of silicon in the coating was *** increasing Si content, the coating microstructure gradually evolved from continuous columnar to discontinuous columnar and quasi-equiaxed crystals; accordingly, the coating inner stress first declined sharply and then kept almost constant. Both the coating hardness and the friction coefficient have the same change tendency with the increase of the Si content, namely increasing at first and then decreasing. The Cr–Si–N coating presented the highest hardness and average friction coefficient for an Si content of about 9.7 at.%, but the wear resistance decreased slightly due to the high *** above phenomenon was attributed to a microstructural evolution of the Cr–Si–N coatings induced by the silicon addition.

关键词： Cr–Si–N coating High-power impulse magnetron sputtering(HiPIMS) Pulsed DC magnetron sputtering Mechanical property Friction coefficient

Atomic layer deposition for nanoscale oxide semiconductor thin film transistors:review and outlook

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International Journal of Extreme Manufacturing 2023年第1期5卷 153-180页

作者： Hye-Mi kim dong-Gyu kim Yoon-Seo kim Minseok kim Jin-Seong Park Division of Materials Science and Engineering Hanyang University222 Wangsimni-roSeongdong-guSeoul 04763Republic of Korea

Since the first report of amorphous In–Ga–Zn–O based thin film transistors,interest in oxide semiconductors has *** offer high mobility,low off-current,low process temperature,and wide flexibility for compositions and ***,depositing oxide semiconductors using conventional processes like physical vapor deposition leads to problematic issues,especially for high-resolution displays and highly integrated memory *** approaches have limited process flexibility and poor conformality on structured *** layer deposition(ALD)is an advanced technique which can provide conformal,thickness-controlled,and high-quality thin film ***,studies on ALD based oxide semiconductors have dramatically increased *** so,the relationships between the film properties of ALD-oxide semiconductors and the main variables associated with deposition are still poorly understood,as are many issues related to *** this review,to introduce ALD-oxide semiconductors,we provide:(a)a brief summary of the history and importance of ALD-based oxide semiconductors in industry,(b)a discussion of the benefits of ALD for oxide semiconductor deposition(in-situ composition control in vertical distribution/vertical structure engineering/chemical reaction and film properties/insulator and interface engineering),and(c)an explanation of the challenging issues of scaling oxide semiconductors and ALD for industrial *** review provides valuable perspectives for researchers who have interest in semiconductor materials and electronic device applications,and the reasons ALD is important to applications of oxide semiconductors.

关键词： atomic layer deposition(ALD) oxide semiconductor thin film transistor(TFT)

Preparation of patterned SiC and SiCN microstructures

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Science China(Technological Sciences) 2006年第2期49卷 164-171页

作者： SUNG In-kyung kim dong-pyo Department of Fine Chemical Engineering and Chemistry of Chungnam National University TaejonSouth Korea 305-764

Patterned SiC and SiCN microstructures were successfully fabricated on the silicon substrates by using polydimethylsiloxane (PDMS) elastometric stamp as template, polycarbosilane (PCS) and polysilazane (PSZ) as preceramic polymers. The preparing process was followed by precursor infiltration, the curing of the precursor, demolding of the template and pyrolysis of the cured preceramic polymer pattern. It shows that the dimen- sions of the ceramic patterns can be tailored by using the PDMS molds with different di- mensions. The produced ceramic microstructures can be potentially applied in high tem- perature and high pressure environments due to the advanced properties of the SiC and SiCN ceramics.

关键词： micro-fabrication technique, soft lithography, elastomeric stamp, non-oxide ceramics, patterning.

Phylogenetic relationship,biogeography,and conservation genetics of endangered Fraxinus chiisanensis(Oleaceae),endemic to South Korea

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Plant Diversity 2022年第2期44卷 170-180页

作者： Changkyun kim dong-Kap kim Hang Sun Joo-Hwan kim Plant Research Division Honam National Institute of Biological ResourcesMokpo 58762Republic of Korea Forest Biodiversity Division Korea National ArboretumPocheon 11186Republic of Korea CAS Key Laboratory for Plant Biodiversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650204YunnanPR China Department of Life Science Gachon UniversitySeongnam 13120Republic of Korea

Endemic plants are important for understanding phylogenetic relationships,biogeographical history,and genetic variation because of their restricted distribution and their role in conserving ***,we investigated the phylogenetic relationships of the Korean endemic Fraxinus chiisanensis by reconstructing the molecular phylogeny of Fraxinus based on two nuclear DNA(nrITS and phantastica)and two chloroplast DNA(psbA-trnH and rp132-trnL)*** our fossil-calibrated phylogenetic framework,we also inferred the biogeographical history of *** provide a scientific basis for the conservation of ***,we determined the levels of genetic diversity and genetic differentiation in this *** information from nuclear and chloroplast DNA sequence data,our molecular phylogenetic analyses identified *** as a genetically distinct unit from its sister group,Fraxinus platypoda from *** molecular dating analyses using nuclear and chloroplast DNA data sets show *** diverged from its sister *** in the Early or Middle Miocene and differentiated in the Late Miocene on the Korean *** results suggest that the divergence of *** was associated with the submergence of the East China Sea land bridge and enhanced monsoons in East *** compared to ***,*** exhibits low genetic diversity within populations and high genetic differentiation among *** results help us to understand the evolutionary history of *** and to develop a conservation strategy for this species.

关键词： East China Sea land bridge Endemic species Fraxinus chiisanensis Korean Peninsula Genetic diversity Biogeography

BIOCOMPATIBILITY OF A PDMS-COATED MICRO-DEVICE:BLADDER VOLUME MONITORING SENSOR

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Chinese Journal of Polymer Science 2012年第2期30卷 242-249页

作者： dong Sup Lee Su Jin kim Jun Ho Sohn In Gul kim Sae Woong kim dong Wan Sohn Jong Hyun kim Bumkyoo Choi Department of Urology St.Vincent's HospitalCollege of Medicinethe Catholic University of KoreaSuwonKorea Department of Urology Seoul St.Mary's HospitalCollege of Medicinethe Catholic University of KoreaSeoulKorea Department of Urology Yeouido St.Mary's HospitalCollege of Medicinethe Catholic University of KoreaSeoulKorea Department of Mechanical Engineering Sogang UniversitySeoulKorea

We evaluated the biocompatibility of a dimethylpolysiloxane-coated micro-device which had been designed for monitoring real-time bladder volume in previous studies. The extract assay with dimethylpolysiloxane which had been used for coating the micro-device to measure the bladder volume was performed as an in vitro cytotoxicity test. For in vivo biocompatibility testing, the inflammatory responses around the implantation site of the micro-device in subcutaneous tissue of rat were assessed by light microscope with H＆E stain and fluorescence microscope with ED1 stain and von Willebrand factor stain. The averages of cell viability in dimethylpolysiloxane group were 84.6% and 82.3% at 24 h and 72 h incubation, respectively. The qualitative evaluations with light and fluorescence microscope revealed that the inflammatory changes peaked during 2 weeks but almost disappeared at 4 weeks after implantation of devices. The quantitative evaluations for granulation layer formation and neovascularization showed that the thickness of the layer in dimethylpolysiloxane group peaked during 2 weeks but it came to be stabilized at 4 weeks as thin as at 2 weeks in control group, and the frequency of neovascularization was higher in dimethylpolysiloxane group than in control group but it was not increased with time. The dimethylpolysiloxane-coated micro-device is thought be a reliable bio-medical device.

关键词： Dimethylpolysiloxane Devices Biocompatibility testing.

DISCRETE MINUS ONE NORM LEAST-SQUARES FOR THE STRESS FORMULATION OF LINEAR ELASTICITY WITH NUMERICAL RESULTS

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Journal of Computational Mathematics 2003年第6期21卷 689-702页

作者： Sang dong kim Byeong Chun Shin Seokchan kim Gyungsoo Woo Department of Mathematics Kyungpook National University Taegu 702-701 KoreaDepartment of Mathematics Chonnam National University Kwangju 500-757 KoreaDepartment of Mathematics Changwon Nationnal University Changwon 641-773 KoreaDepartment of Mathematics Changwon Nationnal University Changwon 641-773 Korea

This paper studies the discrete minus one norm least-squares methods for the stress formulation of pure displacement linear elasticity in two dimensions. The proposed least-squares functional is defined as the sum of the L2- and H-1-norms of the residual equations weighted appropriately. The minus one norm in the functional is replaced by the discrete minus one norm and then the discrete minus one norm least-squares methods are analyzed with various numerical results focusing on the finite element accuracy and multigrid convergence performances.

关键词： H-1 least-squares Linear elasticity Multigrid method.

Slip-enhanced Reverse Electrodialytic Power Generation in Ion-selective Nanochannels

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Journal of Thermal Science 2013年第1期22卷 36-41页

作者： Byeongdong Kang Jaisuk Yoo Hyun Jung kim dong-Kwon kim Department of Mechanical Engineering Ajou University

Power generation by reverse electrodialysis in ion-selective nanochannels is numerically investigated. Especially,in the present study, the influence of hydrodynamic slip at the surface of nanochannels is investigated. The current-potential characteristics of the nanochannels are calculated by solving several governing equations:Nernst-Planck equation for the ionic concentrations, the Poisson equation for the electric potential, and the Navier-Stokes equation for the diffusioosmotic flow. Hydrodynamic slip is applied as the boundary condition at the surface of nanochannels. As the slip length increases, the diffusioosmotic flow velocity and electrical conductance of ions increase because the friction at the surface of nanochannels decreases. It is shown that the power generation is enhanced by 44% with a moderate 100nm slip length by using a nanochannel with 10nm height.

关键词： Reverse electrodialysis Ion-selective nanochannel Power generation Slip length

Study of Spiral Flow Generated through an Annular Slit

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Journal of Thermal Science 2005年第2期14卷 97-102页

作者： Tae Hun kim Shigeru MATSUO Toshiaki SETOGUCHI Heuy-dong kim Graduate school of Science and Technology Saga University 1Honjo-machiSaga shiSaga 840-8502JapanDepartment of Mechanical Engineering Saga University1Honjo-machiSaga shiSaga 840-8502JapanDepartment of Mechanical Engineering Saga University1Honjo-machiSaga shiSaga 840-8502JapanSchool of Mechanical Engineering College of Natural ScienceAndong National University388Song Cheon DongAndongKyung PookKorea

The effect of pressurized air inlets in the reservoir upstream of the annular slit on characteristics of the axial and tangential velocity components is investigated numerically, and the mechanism of occurrence of spiral nozzle flow is clarified. In simulations, Unified Platform for Aerospace Computational Simulation (UPACS) is used. The governing equations under consideration are the unsteady compressible Navier - Stokes. A second-order finite volume scheme with MUSCL (Roe scheme) is used to discretize the spatial derivatives, and a second order-central difference scheme for the viscous terms, and a MFGS (Matrix Free Gauss Seidel) is employed for time integration. Spalart-Allmaras model was used as a turbulence model. The results obtained are compared with velocity distributions in the experiment measured by the two-component fiber optic laser Doppler velocimeter system. The existence of discrete pressurized air inlets that leads to the occurrence of asymmetrical characteristics is a very important factor for the formation of spiral flow.

关键词： spiral nozzle flow Coanda effect convergent nozzle annular slit simulation.

Creep and tensile properties of press molding joined GMT-sheets

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Transactions of Nonferrous Metals Society of China 2011年第A01期21卷 170-174页

作者： Jin-Woo kim dong-Gi LEE Center for NDE Iowa State University Department of Mechatronics Engineering Chosun University

GMT-sheet is used in automobile bumper with high rigidity and strength, and its joining strength is influenced by lap length, one of the joined molding conditions. Fracture strength was calculated by dividing fracture load with cross-sectional area. Total five repeated measurements were made to obtain the average value. Tensile test was conducted at room temperature for 10 specimens. In addition, the effect of compression ratio on creep and tensile performance during lap joined molding was discussed. With increasing lap length, the lap joining efficiency of GMT-sheet was increased. However, higher compression ratio reduced the joining efficiency. Creep test on GMT-sheet showed abrupt fracture without tertiary creep. This can be explained by the weak thermal resistance of the resin. If GMT-sheet was exposed to high temperature for a long time, it was easily failed by external force.

关键词： GMT-sheet randomly oriented composite unidirectional oriented composite compression ratio lap joint