• Title/Summary/Keyword: sigH

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Reversed-Phase High Performance and Liquid Chromatographic Separation of the Enantiomers of Terbutaline by Derivatization with 2,3,4-Tetra-o-acetyl-\beta-glucopyranosyl Isothiocyanate

  • Kim, Kyeong-Ho;Kim, Dong-Sig;Hong, Seon-Pyo;Keon, Oh-Seung
    • Archives of Pharmacal Research
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    • v.23 no.1
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    • pp.26-30
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    • 2000
  • The enantiomers of the bronchodilator terbutaline were separated by reversed-phase high performance liquid chromatograhy after derivatization with 2,3,4,6-tetra-O-acetyl-\beta-D-glucopyranosyl isothiocyanate(GITC) reagent. The derivatization proceeded quantitatively within 1 h at room temperature. The corresponding diastereomeric thiourea derivatives were well resolved on an ODS column with acetonitrile-acetate buffer as a mobile phase. Elution orders of the diastereomers were confirmed by derivatization of R-(-)-terbutaline and S-(+)-terbutaline which were collected by semi-preparative chiral HPLC using Sumichiral OA-4700 column. The native fluorescence of terbutaline was quenched by derivatization with GITC. The detection limit was 25ng when monitored at UV 278 nm.

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A 42-GHz Wideband Cavity-Backed Slot Antenna with Thick Ground Plane

  • Lee, Jong-Moon;Cho, Young-Heui;Pyo, Cheol-Sig;Choi, Ik-Guen
    • ETRI Journal
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    • v.26 no.3
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    • pp.262-264
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    • 2004
  • We investigate the characteristics of a wideband and high-gain cavity-backed slot antenna in terms of the reflection coefficients, radiation patterns, and gain. A cavity-backed slot antenna structure includes baffles, reflectors, and thick ground planes. The measured gain and bandwidth of a 10-dB return loss in a cavity-backed $2{\times}2$ array slot antenna with $h_1=2 $mm, d=2 mm are 15.5 dBi and nearly 27%, respectively, at 42 GHz. Baffles and reflectors are used to increase antenna gain, thus reducing the coupling among the slots on the thick ground plane.

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Characteristics of the Inhibitory Action of Protease Inhibitors on the Glucose-6-phosphate Transporter

  • Choi, Joon-Sig;Shin, Jeong-Sook;Choi, Hong-Sug;Park, Jong-Sang
    • BMB Reports
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    • v.30 no.2
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    • pp.157-161
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    • 1997
  • The present paper reports characteristics and specificity of the inhibitory action of $N^{\alpha}-tosyl-L-lysine-chloromethyl\;ketone$ (TLCK) and $N^{\alpha}-tosyl-L-phenylalanine-chloromethyl\;ketone$ (TPCK) on the glucose6-phosphate transporter of rat liver microsomes. The TLCK-induced inhibition was pH dependent. The inhibition constants for TPCK were determined by following pseudo-Lst order reaction mechanism. The inhibition was protected by preincubation with excess amount of glucose-6-phosphate. The results proved that (a) TLCK inactivates the microsomal glucose-6-phosphate transporter, (b) the inhibition results from the modification of sulfhydryl groups of the transporter.

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Analysis of High Vibration in Nuclear Turbine-Generator (원자력 발전소 터빈-발전기 고진동 저감에 대한 고찰)

  • Lee, Woo-Kwang;Ko, Woo-Sig;Kim, Kye-Yean;Koo, Jae-Raeyang
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.05a
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    • pp.46-50
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    • 2007
  • The nuclear power plant's turbine-generator system had been suffered form some problems, such as high shaft vibration, generator casing crack, stator coil water leakage, high $H_2$ gas consumption rate. Those kinds of problems were related to high vibration. So nuclear plant decided to replace generator in order to reduce rotor high vibration and high thermal sensitivity. A series of effort to reduce turbine-generator vibration was carried out as followings, first of all, replacement of generator, analysis of turbine-generator vibration, LP B rotor shop balancing, improvement of LP B/Gen coupling run-out, improvement of Generator basement and field balancing. Finally the nuclear turbine-generator's shaft vibration was reduced below $60{\mu}m$ from over $200{\mu}m$ which is very excellent vibration in nuclear turbine-generator in Korea.

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Effect of Sucrose and Polybrene on the Gene Transfer into Procine Oocytes using Retroviral Vector

  • Kim, Kang-Sig;Kim, Teoan;Ju, Jin-Young;Kim, Kwang-Sung;Lee, Hoon-Taek;Chung, Kil-Saeng
    • Proceedings of the KSAR Conference
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    • 2002.06a
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    • pp.23-23
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    • 2002
  • In vitro matured porcine oocytes have very small volume of perivitellinespace(PVS). In these respect, the effects of sucrose and polybrene on the efficiency of gene transfer were investigated. As a gene (hGH) transfer vehicle, Vesicular stomatitis virus glycoprotein pseudotyped retroviral vector (VSV-G) was used. Sucrose treatment have no detrimental effect on the rates of cleavage and following development and induced the enlargement of PVS resulting the efficient introduction of retroviral vector stocks into PVS. (omitted)

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Conformal $Al_2$O$_3$ Nanocoating of Semiconductor Nanowires by Atomic Layer Deposition

  • Hwang, Joo-Won;Min, Byung-Don;Kim, Sang-Sig
    • KIEE International Transactions on Electrophysics and Applications
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    • v.3C no.2
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    • pp.66-69
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    • 2003
  • Various semiconductor nanowires such as GaN, GaP, InP, Si$_3$N$_4$, SiO$_2$/Si, and SiC were coated conformally with aluminum oxide (Al$_2$O$_3$) layers by atomic layer deposition (ALD) using trimethylaluminum (TMA) and distilled water ($H_2O$) at a temperature of 20$0^{\circ}C$. Transmission electron microscopy (TEM) revealed that A1203 cylindrical shells conformally coat the semiconductor nanowires. This study suggests that the ALD of $Al_2$O$_3$ on nanowires is a promising method for preparing cylindrical dielectric shells for coaxially gated nanowire field-effect transistors.

Al2O3 Nano-Coating by Atomic Layer Deposition

  • Min Byung-Don;Lee Jong-Soo;Kim Sang-Sig
    • Transactions on Electrical and Electronic Materials
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    • v.4 no.3
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    • pp.15-18
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    • 2003
  • Aluminum oxide ($Al_2O_3$) materials were coated conformally on ZnO nanorods by atomic layer deposition (ALD). The ZnO nanorods were first synthesized on a Si(100) substrate from ball-milled ZnO powders by a thermal evaporation procedure. $Al_2O_3$ films were then deposited on these ZnO nanorods by ALD at a substrate temperature of $300^{\circ}C$ using trimethylaluminum (TMA) and distilled water ($H_2O$). Transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) images of the deposited ZnO nanorods revealed that amorphous $Al_2O_3$ cylindrical shells surround the ZnO nanorods. These TEM images illustrate that ALD has an excellent capability to coat any shape of nanorods conformally.

CHP Effects on Reliability and Environment in Long Term Generation Expansion Planning (전력수급기본계획에 열병합발전 설비의 적정 구성비율에 의한 신뢰도 및 환경효과 분석)

  • Kim, Yong-Ha;Son, Hag-Sig;Kang, Geun-Young;Na, In-Gyu;Jo, Sung-Lin;Kim, Mi-Ye;Woo, Sung-Min
    • Proceedings of the KIEE Conference
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    • 2005.11b
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    • pp.61-63
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    • 2005
  • Because of an energy efficiency and a greenhouse gas reduction effectiveness at the same time, the concern have been enlarged in the CHP But, the approach of a policy side have been achieved about the South Korea currently. This papers considered a policy side and economic side. As a result of Long Term Generation Expansion Planning from calculating the component ratio of adequate CHP, Reliability of the power system and influence of environments was analyzed.

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Error Analysis of Terrestrial LiDAR According to the Measurement Angle (지상 LiDAR 측정 각도에 따른 오차분석)

  • Kim, Jong-Suk;Sohn, Hong-Gyoo;Kim, Seong-Sam;Cho, Hyung-Sig;Jeong, Seong-Su
    • Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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    • 2008.10a
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    • pp.324-328
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    • 2008
  • 지상 LiDAR(Light Detection And Ranging)는 정밀하고 빠르게 물체의 3차원 형상을 측량할 수 있는 시스템이다. 기본적으로 종전의 레이저 측량기의 기능을 갖고 있으며, 초당 최대 $5,000{\sim}50,000$ point의 레이저를 대상체 표면에 발사하여 대상체면에 투사한 레이저의 간섭이나 반사를 이용하여 대상체면상의 point could의 공간정보를 취득하는 관측방식의 3차원 정밀 측량으로서 대상체의 표면으로부터 상대적인 3차원(X, Y, Z) 지형공간좌표를 각각의 Point 데이터로 기록한다. 이러한 측정방법은 레이저가 반사되어 돌아오는 시간을 계산하여 거리를 결정하고 ${\theta}_h$(수평각)과 ${\theta}_v$(수직각) 각도만큼 수평, 수직으로 회전하여 측정한 점의 위치를 결정하므로 데이터 취득 각도에 따른 오차가 발생하게 된다. 본 연구 에서는 지상LiDAR 데이터 취득각도에 따른 오차 시뮬레이션 실시하여 실제 실험과의 비교 및 입사각에 따른 정확도 분석을 실시하였다.

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