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Acta Geochimica 2017年第3期36卷 367-369页

作者： Sujin kang Kyoung-Hoon shin Jung-Hyun Kim Department of Marine Science and Convergence Technology Hanyang University Ansan Korea Korea Polar Research Institute 26 Songdomirae-ro Yeonsugu Incheon Korea

We investigated the occurrence and distribution of terrestrial-derived hydroxylated isoprenoid glycerol dialkyl glycerol tetraethers(OH-GDGTs) in the Han River system and their potential impact on the application of the ring index of OH-GDGTs(RI-OH) as a sea surface temperature(SST) proxy in the eastern Yellow Sea. Thereby, we analyzed various samples collected along the Han River and from its surrounding areas(South Korea, n = 34). The OHGDGTs were found in all samples investigated. OH-GDGT-0 was the dominant OH-GDGT component in the estuary and marine samples while OH-GDGT-2 was generally dominant in the soils, the lake sediments and the river suspended particulate matter(SPM). Our results thus suggests a possible warm bias of the RI-OH-derived summer SSTs in the coastal zone to which a large amount of terrestrial organic matter is being supplied. Further studies are necessary to better assess the applicability of the RI-OH proxy in the eastern Yellow Sea.

关键词： Hydroxylated isoprenoid glycerol dialkyl glycerol tetraethers(OH-GDGTs) Sea surface temperature(SST) Han river Yellow Sea

High-efficiency technique based on dielectrophoresis for assembling metal,semiconductor,and polymer nanorods

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第5期12卷 368-373页

作者： Heng YUAN Kyu-jin KIM Won-seok kang Byoung-ho kang Se-hyuk YEOM Jae-ho KIM shin-won kang School of Electrical Engineering and Computer Science Kyungpook National University 1370 Sankyuk-dong Bukgu Daegu 702-701 Korea) Department of Molecular Science and Technology Ajou University San s.Woncheon-dongYeongtong-guSuwon 443-749Korea School of Electronic Engineering College oflT Engineering Kyungpook National University 13 70 Sankyuk-dong Bukgu Daegu 702-701 Korea

This paper presents a high-efficiency technique based on dielectrophoresis (DEP) for assembling metal, semiconductor, and polymer nanorods, which are synthesized by electrochemical deposition (ECD). The assembly patterns of these nanorods (width: 20 nm; length: 7 μm) were designed using a finite element method (FEM) simulation tool. Further, these nanorods were used in our experiment after their assembly patterns were fabricated. The assembly yield was found to be approximately 70% at an AC voltage of 30 Vp-p and at frequencies of 20 and 30 kHz, and the DC voltage prevented the random alignment of the nanorods at the edge of the assembly pattern. Moreover, the above-mentioned nanorods, which had different permittivities, were found to have similar assembly yields. The proposed method can be improved and applied to nanostructure device fabrication.

关键词： Nanorod Assembly Dielectrophoresis (DEP) Finite element method (FEM) Electrochemical deposition (ECD) method

Numerical characterization of heat transfer in closed-loop vertical ground heat exchanger

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Science China(Technological Sciences) 2010年第1期53卷 111-116页

作者： Chulho LEE Hujeong GIL Hangseok CHOI shin-Hyung kang School of Civil Environmental and Architectural EngineeringKorea University5-GaAnam-DongSeongbuk-GuSeoul 136-713Republic of Korea Pyungsan SI Co. Ltd.1337-31 Seocho-DongSeocho-GuSeoul 137-860Republic of Korea Department of Mechanical Engineering Konyang University119Deahak-RoNonsanChungnam 320-711Republic of Korea

A series of numerical analyses has been performed on the characteristics of heat transfer in a closed-loop vertical ground heat exchanger(U-loop).A 2-D finite element analysis was conducted to evaluate the temperature distribution over the cross section of the U-loop system involving high-density polyethylene(HDPE) pipe/grout/soil to compare the sectional efficiency between the conventional U-loop and a new latticed HDPE pipe system,which is equipped with a thermally insulating lattice in order to reduce thermal interference between the inlet and outlet *** addition,a 3-D finite volume analysis(FLUENT) was adopted to simulate the operation of the closed-loop vertical ground heat exchanger with the consideration of the effect of a distance between the inlet and outlet pipes,grout's thermal properties,the effectiveness of the latticed HDPE pipe system,and the rate of circulation *** was observed that the thermal interference between the two strands of U-loop is of importance in enhancing efficiency of the ground heat ***,it is recommended to modify the configuration of the conventional U-loop system by equipping the thermally insulating lattice between the two pipe strands.

关键词： ground heat exchanger HDPE pipe latticed pipe sectional efficiency

Influence of rice straw burning on the levels of polycyclic aromatic hydrocarbons in agricultural county of Taiwan

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Journal of Environmental Sciences 2009年第9期21卷 1200-1207页

作者： Chia-Hsiang Lai kang-shin Chen Hsin-Kai Wang Department of Health Safety and Environmental Engineering Central Taiwan University of Science and Technology Institute of Environmental Engineering Sun Yat-Sen University

Atmospheric particulate and polycyclic aromatic hydrocarbons （PAHs） size distribution were measured at Jhu-Shan （a rural site） and Sin-Gang （a town site） in central Taiwan during the rice straw burning and non-burning periods. The concentrations of total PAHs accounting for a roughly 58% （34%） increment in the concentrations of total PAHs due to rice-straw burning. Combustion-related PAHs during burning periods were 1.54-2.57 times higher than those during non-burning periods. The mass median diameter （MMD） of 0.88-1.21 μm in the particulate phase suggested that rice-straw burning generated the increase in coarse particle number. Chemical mass balance （CMB） receptor model analyses showed that the primary pollution sources at the two sites were similar. However, ricestraw burning emission was specifically identified as a significant source of PAH during burning periods at the two sites. Open burning of rice straws was estimated to contribute approximately 6.3%-24.6% to total atmospheric PAHs at the two sites.

关键词： rice straw open burning polycyclic aromatic hydrocarbons (PAHs) receptor mod

Machining characteristics of complex prism pattern on electroplated roll by copper

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中国有色金属学会会刊：英文版 2009年第B9期19卷 288-294页

作者： Tae-Jin JE Sang-Cheon PARK kang-Won LEE Yeong-Eun YOO Doo-Sun CHOI Kyung-Hyun WHANG myung-Chang kang Nano-Machining Laboratory Division of Nano-Mechanical Systems Korea Institute of Machinery and Materials Nano-Mechatronics Department University of Science and TechnologySinseongnoYouseong-GuDaejeonKorea National Core Research Center for Hybrid Materials Solution Pusan National University

The BLU (back light unit) is the core component of the LCD for notebook, mobile-phone, navigation, as well as large sized TV, PID (public information display), etc. In order to enhance optical efficiency of LCD, optical films with the uniform prism patterns have been used for BLU by stacking two films up orthogonally. In this case, light interference-phenomenon occurred such as Morie, wet-out, u-turning, etc. It caused several problems such as low brightness, spots and stripes in LCD. Recently, the high-luminance micro complex prism patterns are actively studied to avoid the light interference-phenomenon and enhance the optical efficiency. In this study, the roll master to manufacture complex micro prism pattern film was machined by using the high precision lathe. The machined patterns on the roll master were 50, 45, 40, 35, 30, 25, 20, 15, 10 and 5 μm in the pitch with 25.0, 22.5, 20.0, 17.5, 15.0, 12.5, 10.0, 7.5, 5.0 and 2.5 μm in the peak height, respectively. The roll was 2 000 mm in length and 320 mm in diameter. The electroplated roll by copper and the natural single crystal diamond tool was used for machining the patterns. The cutting force was measured and analyzed for each cutting condition by using the dynamometer. The chips and the surfaces after being machined were analyzed by SEM and microscope.

关键词：车床加工微棱镜铜电镀特征光学效率光学薄膜笔记本电脑金刚石工具

Characteristics of damaged layer in micro-machining of copper material

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中国有色金属学会会刊：英文版 2009年第B9期19卷 295-300页

作者： Dong-Hee KWON Jeong-Suk KIM myung-Chang kang Se-Hun KWON Jong-Hwan LEE School of Mechanical Engineering Pusan National University National Core Research Center for Hybrid Materials Solution Pusan National University Department of Mechatronics Busan College of Korea Polytechnic Ⅶ

The study on damaged layer is necessary for improving the machinability in micro-machining because the damaged layer affects the micro mold life and micro machine parts. This study examined the ultra-precision micro-machining characteristics, such as cutting speed, feed rate and cutting depth, of a micro-damaged layer produced by an ultra-high speed air turbine spindle. The micro cutting force, surface roughness and plastic deformation layer were investigated according to the machining conditions. The damaged layer was measured using optical microscope on samples prepared through metallographic techniques. The scale of the damaged layer depends on the cutting process parameters, particularly, the feed per tooth and axial depth of the cut. According to the experimental results, the depth of the damaged layer is increased by increasing the feed per tooth and cutting depth, also the damaged layer occurs less in down-milling compared with up-milling during the micro-machining operation.

关键词：机械加工性微观特征损伤层铜材样品制备技术微型机器切削速度切削深度

Distribution of electric field for carbon nanotube assembly: Experiments (II)

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 121-125页

作者： Soongeun KWON Soo-Hyun KIM Kwang-ho KIM myung-chang kang Hyung-woo LEE Department of Mechanical Engineering Korea Advanced Institute of Science and Technology (KAIST) Daejeon 305-701 Korea National Core Research Center for Hybrid Materials Solution Pusan National University

The distribution effect of electric field on the alignment and attachment of carbon nanotubes （CNTs） were investigated. The experimental results were compared with the simulation results according to three different shaped electrodes. In previous simulation, the round shaped electrodes were expected to be more effective for aligning and attaching a single CNT between two electrodes than conical or rectangular shaped electrodes. To verify the simulation results, three different shaped electrodes were introduced and a single multi-walled carbon nanotube （MWNT） was attached. The optimal conditions for aligning and attaching MWNTs such as the frequency, applied voltage and concentration of MWNTs solution were investigated. Through repeated experiments, frequency of 100 kHz-10 MHz, applied voltage of 0.3-1.3 V^s/~m, concentration of 5 ktg/mL in MWNTs solution were obtained as a possible condition range to attach MWNTs. Under these conditions, the yield of MWNTs attachment between two electrodes was up to 70%. In previous simulation, furthermore, it was verified that the size of the stable or quasi-stable region made CNTs aligned and attached on different shaped electrodes from the comparison of the experimental and simulation results. Most single MWNT attachment was accomplished on the round shaped electrodes.

关键词： carbon nanotubes dielectrophoresis round shaped electrode simulation

Dielectrophoretic assembly of semiconducting single-walled carbon nanotube transistor

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 126-129页

作者： Se-Hun KWON Young-Keun JEONG Soongeun KWON myung-Chang kang Hyung-Woo LEE National Core Research Center for Hybrid Materials Solution Pusan National University Department of Mechanical Engineering Korea Advanced Institute of Science and Technology (KAIST) Daejeon 305-701 Korea

A novel burning technique for making a semiconducting single-walled carbon nanotubes （SWNTs） transistor assembled by the dielectrophoretic force was suggested. The fabrication process consisted of two steps. First, to align and attach a bundle of SWNTs between the source and drain, the alternating （AC） voltage was applied to the electrodes. When a bundle of SWNTs was connected between two electrodes, some of metallic nanotubes and semi-conducing nanotubes existed together. The second step is to burn the metallic SWNTS by applying the voltage between two electrodes. With increasing the voltage, more current flowed through the metallic SWNTs, thus, the metallic SWNTs burnt earlier than the semiconducting one. This technique enables to obtain only semi-conducting SWNTs connection in the transistor. Through the 1--V characteristic graph, the moment of metallic SWNTs burning and the characteristic of semi-conducing nanotubes were verified.

关键词： single-walled carbon nanotube (SWNT) semi-conducting carbon nanotube burning technique dielectrophoresis

Structural considerations in friction welding of hybrid Al_2O_3-reinforced aluminum composites

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 42-46页

作者： In-Duck PARK Choon-Tae LEE Hyun-Soo KIM Woo-Jin CHOI myung-Chang kang Busan Metropolitan City Hall Fundamental Industries Division 2001 Jungang-ro Yeonje-gu Busan 611-735 Korea Department of Automotive & Mechanical Engineering Silla University Research & Development Center Sam-Ho precision 1256-1 Daejeo2-dong Gangseo-gu Busan 618-807 Korea National Core Research Center for Hybrid Materials Solution Pusan National University

Comparative studies on the relationship between the welding parameters and joining efficiency in the friction welding of hybrid Al203-reinforced aluminum composites were conducted. Metal matrix composites （MMCs） with 37% （volume fraction） aluminum particle were joined by friction welding. The results show that the effects of the rotation speed on the reduction rate of particle size are greater than those of the upset pressure, and the area of the MMC weld zone decreases as the joining efficiency increases, while it is considered that the joining efficiency does not increase as the reduction rate of particle size decreases. During the macro-examination of the bonding interlace, a gray discolored region was observed on the bonding interface, and the center of the region was dark gray. After the micro-examination of the bonding interface, base metal made some second particulate formed by condensed alumina particulate but discoloration part distributed minute alumina particulate without second particulate. Consequently, it was also observed that rotational speed of 3 000 r/min and upset pressure of 63.6 MPa showed a very ***.

关键词： friction welding hybrid aluminum composite bonding interface joining efficiency metal matrix composite

Effects of betaine on etnanol-stimulated secretion of IGF-I and IGFBP-1 in rat primary hepatocytes: involvement of p42/44 MAPK activation

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World Journal of Gastroenterology 2006年第11期12卷 1718-1722页

作者： Myeong Soo Lee myung-Sunny Kim Soo Young Park Chang-Won kang Complementary Medicine Peninsula Medical School Universities of Exeter and PlymouthExeterEX2 4NTUnited Kingdom Korea Food Research Institute Kyongki-do 463-746Republic of Korea Department of Animal Resources and Biotechnology Chonbuk National University Jeonju 561-756Republic of Korea Department of Physiology College of Veterinary Medicine Chonbuk National UniversityJeonju 561-756Republic of Korea

AIM： To evaluate the effects of betaine on the ethanolinduced secretion of IGF-I and IGFBP-1 using radioimrnunoassay and Western blotting, respectively, in primary cultured rat hepatocytes. METHODS： Hepatocytes isolated from male SpragueDawley rats were incubated with various concentrations of ethanol and PD98059 procedures. The hepatocytes were also treated with different doses of betaine （10^-5, 10^-4, and 10^-3 mol/L）. We measured IGF-I and IGFBP-1 using radioimmunoassay and Western blotting, respectively. RESULTS： The ethanol-induced inhibition of IGF-I secretion was attenuated by betaine in a concentration-dependent manner in primary cultured rat hepatocytes. At 10^-3 mol/L, betaine significantly increased IGF-I secretion but decreased IGFBP-1 secretion. In addition, p42/44 rnitogen-activated protein kinase （MAPK） activity was accelerated significantly from 10 min to 5 h after treatment with 10^-3 mol/L betaine. Furthermore, the changes in IGF-1 and IGFBP-1 secretion resulting from the increased betaine-induced p42/44 MAPK activity in primary cultured rat hepatocytes was blocked by treatment with the MAPK inhibitor PD98059. Betaine treatment blocked the ethanol-induced inhibition of IGF-I secretion and p42/44 MAPK activity, and the ethanol-induced increase in IGFBP-1 ***： Betaine modulates the secretion of IGF-I and IGFBP-1 via the activation of p42144 MAPK in primary cultured rat hepatocytes. Betaine also alters the MAPK activations induced by ethanol.

关键词： Betaine IGF-I IGFBP-1 p42/44 MAPK Hepatocytes Ethanol