• Journal of the Korean Institute of Gas
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• v.5 no.4 s.16
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• pp.85-91
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• 2001

This paper presents safety analysis of LNG leakage in a prestressed concrete outer tank, which is strongly related on the leak checking effects of the PC structure with and without a residual compression zone based on the BS 7777 codes. The full containment type outer tank which is constructed by a prestressed concrete may be destroyed by leaked cryogenic fluids. The FE calculated results show that the total leak checking time of the PC structure with $10\%$ residual compression zone is about 9 days for $-162^{\circ}C$ liquids. But, three primary pumps in an inner tank may operate to send cryogenic fluids for 6 days, which are stored in an inner tank of $140,000m^3$ capacity This means that the prestressed concrete outer tank may be safe for $-162^{\circ}C$ cryogenic fluids leaked from the demolished inner tank.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.254-254
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• 2010

Cu-Pc(copper(II)-phthalocyanine)는 박막의 형성과정에서 열처리 방식과 온도에 따라 박막의 구조가 변하며, 구조로는 열적으로 준 안정적인 $\alpha$-phase와 열적으로 안정적인 $\beta$-phase가 있다. 본 연구에서는 Cu-Pc 박막의 열적으로 안정적인 $\beta$-phase 구조에 대해 온도 조건 변화에 따른 표면 결정 성장의 특성을 연구하고자 한다. 진공증착 방법 중 하나인 thermal evaporation deposition을 이용하여 glass 기판위에 전열 처리 및 후열 처리에 대해 온도 조건 변화에 따른 $\beta$-phase type의 표면 결정 특성을 연구하였다. Cu-Pc 박막의 성장두께는 50nm 일정한 두께로 fluxmeter 및 thickness monitor를 이용하여 제어하였다. 50nm의 두께에 따른 기판온도를 $100^{\circ}C$, $200^{\circ}C$, $300^{\circ}C$로 전열 처리한 후 각각 전열 처리한 기판온도에 대해 1hour, 2hour, 3hour 후열 처리하여 온도 조건에 따른 박막을 성장한 후, $\beta$-phase type에 대한 결정 구조 및 표면 특성 변화를 분석하였다. 제작된 Cu-Pc의 박막은 $\beta$-phase type으로, 열처리에 따른 $\beta$-phase transition 현상을 연구하였다. XRD(X-ray diffraction)를 통하여 박막에 대한 결정 구조 분석 및 FE-SEM(field emission scanning electron microscopy)을 이용하여 Cu-Pc 박막의 구조적 결정성과 방향성 등, 표면 상태와 형상구조에 대해 표면의 특성을 분석하며, 광 흡수도(UV-visible absorption spectra)을 이용하여 온도 조건에 따른 투과/흡수 현상을 비교분석하였다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.1
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• pp.74-83
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• 2001

In this study, the optimum structure of a magnetic thin film inductor was designed for application of DC-DC converters. The Ni$\sub$81/Fe$\sub$19/ (at%) alloy was selected as a high-frequency($\geq$MHz) magnetic thin film magnetron sputtering system. As-deposited NiFe thin films show similar magnetic properties compared to bulk NiFe alloys, indicating that they have a good film quality. The optimum design of dolenoid-type magnetic thin film inductors was performed utilizing a Maxwell computer simulator (Ansoftt HFSS V7.0 for PC) and parameters obtained from the magnetic properties of magnetic core materials selected. The high-frequency characteristics of the inductance(L) and quality factor(Q) obtained for the designed inductors through simulation agreed well with those obtained by theoretical calculations, confirming that the simulated result is realistic. The optimum structure of high-performance (Q$\geq$60, L = 1${\mu}$H, efficiency $\geq$90%), high-frequency ($\geq$5MHz), and solenoid-type magnetic thin film inductors was designed successfully.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2004.05a
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• pp.218-226
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• 2004

Solvent extraction and stripping experiments were conducted to separate iron from a spent $FeCl_3$ etching solution containing nickel. In the extraction, PC88A, MIBK and Alamine336 were tested as an extractant in various diluents. Alamine336 salt in toluene led to the highest extraction percentage of iron. Stripping percentage of iron from the loaded organic by Alamine336 increased with decreasing HCl conentration of stripping solution and with increasing volume ratio of aqueous to organic. In the operation of bench scale mixer-settler, 7 extraction stage with 1.0M Alamine336 salt in toluene and 10 stripping stage with 0.01M HCl solution resulted in a stripped solution with 133g/L of iron and in a raffinate with most of nickel together with a small amount of iron when the flow rate ratio of organic to aqueous was 7.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.1026-1031
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• 2004

Acetylcholinesterase inhibitory activity and protective effect against cytotoxicity of PC 12 cell induced by beta-amyloid protein and glutamate were examined in perilla seed methanol extract and its solvent fractions. Methanol extract of perilla seed showed dose-dependent acetylcholinesterase inhibitory activity, with n-butanol fraction showing strongest activity. Perilla seed methanol extract also decreased glutamate- and ${\beta}-amyloid$ protein $(A{\beta})-induced$ cytotoxicities of PC 12 cells dose-dependently. Formation of TBARS induced by $FeSO_{4^-}H_2O_2$ in rat brain was significantly reduced by perilla seed methanol extract, with strongest protective activity formation of TBARS shown in n-butanol fraction. Results suggest perilla seed methanol extract may attenuate actylcholinesterase activity and cytotoxicity induced by glutamate and ${\beta}-amyloid$ protein through suppression of oxidative stress.

• Textile Coloration and Finishing
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• v.14 no.1
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• pp.27-33
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• 2002

The preparations of deodorizing fibers using medal-phthalocyanines have been investigated. The five metal-phthalocyanine derivatives(M-taPc, M=Fe, Co, Ni, Zn, Cu) were prepared in modest to good yields. The metal-phthalocyanine derivative as a deodorant material was introduced to fibers by a dyeing method. The deodorant activity(D.A.) of these deodorizing fibers was measured by chromogenic gas detector tubes. In comparison with untreated fibers, these deodorizing fibers was remarkably effective against $NH_3$ and CH3SH. More than 99% of ammonia can be removed within 20 min. The D.A.(%) of fiber adsorbed M-taPc was more than 80% after 90min.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.606-609
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• 1995

Ferrite cores are often magnetized under DC-biased field because they have been intensively used in electronic circuits such as an inverter circuit and a switching regulator circuit. Thus we investigated the effects of DC-biased field on magnetic properties in the frequency range of DC-100kHz for two kinds of ferrite cores, TDK PC38 and TDK $H_{3}S$, which have different shapes of B-H loop from each other. The magnetic loss per cycle, W/f, in the $H_{3}S$ core decreased with increasing the strength of DC-biased field, although W/f in the PC38 core increased monotonically with DC-biased field. The observed decreasing tendency differs from the previous result for Si-Fe and ferrite cores, and can be attributed to decrease in eddy current loss as well as that in hysteresis loss.

• Journal of Microbiology and Biotechnology
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• v.13 no.1
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• pp.77-84
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• 2003

Chitinase was purified from an antagonistic bacterium Bacillus sp. 7079 by ammonium sulfate precipitation, QAE-Sephadex anion exchange chromatography, Sephadex G-100 gel filtration, and SP-Sephadex cation exchange chromatography. The molecula. weight of purified chitinase (PC-1) was approximately 66.5 kDa on SDS-PACE. PC-1 exhibited optimum pH and temperature of pH 7.5 and $45^{\circ}C$, respectively. More than $80\%$ of PC-1 was stable at pH 5.0 to 9.0, and more than $90\%$ at $40^{\circ}C$. $Fe^2+\;and\;Ca^2+$ inhibited the chitinase activity about $20\%$, and EDTA and p-CMB by about $30\%$, whereas $Ag^+$ inhibited the activity up to $65\%$. The $K_m$ value of PC-1 was 1.215 mg/ml with colloidal chitin as a substrate. We also investigated the effect of PC-1 treated chitin (PCTC) on the pro-inflammatory cytokine gene expression in macrophage RAW 264.7 cells. The expression of IL-$1{\alpha}$ and IL-$1{\beta}$ mRNA gene was investigated using reverse transcriptase polymerase chain reaction (RT-PCR). IL-$1{\alpha}$ and IL-$1{\beta}$ mRNA were induced by the treatment of PCTC and chitin only in RAW 264.7 cells. These expressions were induced as early as 2 h and sustained up to 24 h in RAW 264.7 cells. IL-$1{\alpha}$ and IL-$1{\beta}$ mRNA were more strongly expressed by the treatment of PCTC than chitin treatment alone in RAW 264.7 cells.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.317-318
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• 2008

Cu-Pc유기물 반도체를 얼 진공증착기술로 유리기판위에 40 nm 두께로 적층하였다. 상온에서 적층한 박막과 상온에서 적층한 후 $250^{\circ}C$ 이상의 온도로 후열 처리한 박막과 박막 적층 시 기판의 온도를 $250^{\circ}C$로 고정하여 적층한 박막들을 상호 비교 분석하였다. 적층된 Cu-Pc의 박막의 온도조건에 따라 X-ray diffraction(XRD)의 결정 특성이 $\alpha$-phase와 $\beta$-phase로 뚜렷이 구분되었으며， 자외선-가시광선 영역의 광 흡수도(UV-visible absorption spectra)와 field emission scanning electron microscopy(FE SEM)를 이용하여 결정성장 방향 및 표면 특성 변화를 비교조사하였다.

• Electronics and Telecommunications Trends
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• v.20 no.1 s.91
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• pp.130-138
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• 2005

최근, 디지털 기술의 발전과 인터넷 보급이 활성화 되면서 PC 뿐만 아니라 모든 단말기가 네트워크에 상시 접속되어, 누구든지 시간과 장소에 제약이 없이 다양한 서비스를 제공 받을 수 있는 유비쿼터스환경의 사회로의 진입이 가시화되고 있다. 이러한 기술을 가능하게 하는 핵심 코어 기술 중의 하나가 메모리 기술이다. 최근에 유비쿼터스용 유니버설 메모리가 연구 개발되고 있어 이 기술에 대한 원리와 간단한 구조 및 최근의 기술 동향에 대하여 살펴보고, 향후의 유니버설 메모리 기술의 연구개발 방향에 대하여 언급하였다. 여기서는 유니버설 메모리라고 불리는 차세대의 비휘발성 메모리 중에서 현재 가장주목 받고 있는 MRAM, FeRAM, PRAM의 기본적인 구조에 대해서 설명하고 그 최근의 기술 개발 동향에 대하여 분석하여 언급하고자 한다.