• Fire Science and Engineering
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• v.22 no.4
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• pp.65-69
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• 2008

An accurate knowledge of the flash point is important in developing appropriate preventive and control measures in industrial fire protection. The lower flash points for the n-propanol+formic acid system were measured by Pensky-Martens closed cup apparatus. This binary mixture exhibited MFPB (minimum flash point behavior), which leads to the minimum on the flash point vs composition curve. The Raoult's law and optimization method using Wilson equation were used to predict the lower flash points and were compared with experimental data. The calculated values based on the optimization method were found to be better than those based on the Raoult's law.

• Fire Science and Engineering
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• v.32 no.1
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• pp.1-6
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• 2018

The flash point is one of the most important parameters used to characterize the ignition and explosion hazards of liquids. Flash points were measured for several binary systems containing toluene, including {methanol+toluene}, {ethanol+toluene}, and {1-propanol+toluene}. Experiments were performed according to the standard test method using a SETA closed cup flash point tester. The measured flash points were compared with the predicted values calculated using the following $G^E$ models: Wilson, NRTL, and UNIQUAC. The average absolute deviation between the predicted and measured lower flash point was less than 1.69 K.

• Journal of the Korean Institute of Gas
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• v.18 no.5
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• pp.60-65
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• 2014

The flash point is the major physical property used to characterize the fire hazard of flammable liquid solutions. In the present study, the main focus is on measuring and estimating the flash points for binary flammable mixture. The flash points for n-propanol+propionic acid were measured by Seta flash closed cup apparatus. The experimental data were correlated with the van Laar and NRTL equations through the optimization method. The results estimated by these correlations were compared with the values calculated by the method based on Raoult's law. The optimization method were found to be better than the method based on the Raoult's law.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2007.04a
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• pp.338-342
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• 2007

• Proceedings of the Membrane Society of Korea Conference
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• 2008.05a
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• pp.198-201
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• 2008

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2006.05a
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• pp.475-478
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• 2006

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2006.05a
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• pp.479-482
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• 2006

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2012.10a
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• pp.75-76
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• 2012

• Journal of the Korean Institute of Gas
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• v.14 no.2
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• pp.22-26
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• 2010

In this study, experimental vapor pressures and densities of vapor and liquid phases versus temperature were estimated using PC-SAFT equation. The estimated results were compared with those using PR equation of state. For the vapor phase densities, both equations well predicted the literature data. However, PC-SAFT equation showed better prediction capability for liquid phase densities. In the comparison of vapor-liquid equilibrium prediction capability for the binary systems of methane and ethane, PC-SAFT equation was better than the PR equation.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.28.1-28.1
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• 2011

비휘발성 저항 메모리소자인 ReRAM은 간단한 소자구조와 빠른 동작특성을 나타내며 고집적화에 유리하기 때문에 차세대 메모리소자로써 각광받고 있다. 현재, 이성분계 산화물, 페로브스카이트 산화물, 고체 전해질 물질, 유기재료 등을 응용한 저항메모리소자 응용에 대한 연구가 활발히 진행되고 있다. 그 중 ZnO 박막은 이성분계 산화물로써 조성비가 간단하고, 빠른 동작특성을 나타내며, 높은 저항 변화율을 보이기 때문에 ReRAM에 응용 가능한 재료로써 기대되고 있다. 또한 가시광선 영역에서 광학적으로 투명한 특성을 보이기 때문에 투명소자 응용에도 많은 연구가 진행되고 있다. 본 연구에서는 Metal/Insulator/Metal (Al/ZnO/Al) 구조의 소자를 제작하여 저항 메모리 특성을 평가하였다. Radio frequency (RF) sputter를 이용하여 ZnO 박막을 합성하고 박막의 결정성을 평가하였으며, resistive switching 효과를 관찰하였다. 합성된 박막 내부의 결정성은 메모리 구동 저항에 영향을 주며, 이를 제어하여 신뢰성있는 메모리 효과를 얻을 수 있었다. 특히 박막의 두께를 제어함으로써 구동전압의 변화를 관찰하였으며 소자에 적합한 두께를 평가할 수 있었다. 또한, ZnO 박막 내의 결함에 따른 on/off 저항의 변화를 관찰할 수 있었다. 제작된 저항 메모리소자는 unipolar 특성을 보였으며, 높은 on/off 저항의 차이를 유지하였다. Scanning electron microscope(SEM)을 통해 합성된 박막의 형태를 평가하였고, X-ray diffraction (XRD) 및 transmission electron microscopy (TEM)을 통해 결정성을 평가하였으며, photoluminescence (PL) spectra 분석을 통하여 박막 내부의 결함 정도를 평가하였다. 제작된 소자의 전기적 특성은 HP-4145를 이용하여 측정하고 비교 분석하였다.