• Elastomers and Composites
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• v.48 no.4
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• pp.276-281
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• 2013

Polyester type polyurethane foam modified with acrylic polyol was prepared by quasi prepolymer method. Thermal and dynamic mechanical properties of polyurethane foam were analysed by thermal gravimetric analysis(TGA) and dynamic mechanical analysis(DMA). Also, glass transition temperature was measured by differential scanning calorimeter(DSC). As acrylic polyol contents were increased, thermal stability measured by TGA was slightly decreased. Storage modulus was increased and tan delta was decreased with increasing of acrylic polyol contents.

• Journal of the Korean Society of Combustion
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• v.16 no.3
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• pp.21-26
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• 2011

Thermal analyses are conducted to measure chemical kinetic parameters of an unknown liquid fuel with various components. Thermal Analyses are divided into two different methods such as TGA(Thermo-Gravimetric Analysis) and DSC(Differential Scanning Calorimety). Non-isothermal experimental results are analyzed by adopting TGA and they are filtered by Freeman-Carroll method. As a results of the analysis, chemical parameters of the activation temperature and the reaction order are measured to be 6128.2 K and 1.4, respectively. Furthermore, the chemical kinetic parameters are obtained by a variety of mathematical processing methods. It has been found that they show a little difference depending on the processing method.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.421-424
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• 2011

Thermal Analyses are conducted to measure various factors of a liquid fuel required for numerical analysis. Thermal Analyses are divided into two different methods of TGA (Thermo Gravimetric Analysis) and DSC (Differential Scanning Calorimetry). Non-isothermal experimental results are analyzed using by TGA. The results are filtered by a Freeman Carroll method. At the same time, chemical parameters of unknown liquid fuel, activation temperature and reaction order are measured to 6128.2 K and 1.4, respectively. Furthermore, the parameters can be obtained by various mathematical methods. It is found that tha parameters depend on the processing method.

• Carbon letters
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• v.18
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• pp.62-66
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• 2016

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.773-778
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• 2002

The variance characteristics of the calcium carbonate contents along to the concrete cover depth takes the prediction method of remaining service life of concrete. Calcium carbonate contents were measured by the Thermo Gravimetric/Differential Thermal Analysis method at three point, depth of 0.25cm, 0.75cm, 1.25cm from the surface of concrete. This prediction method contain some assumption that the chemical protection conferred on steel is through a passive protective oxide film which forms on steel in an environment at or above a pH of 10.5$^{4)}$ .

• Journal of the Korean Chemical Society
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• v.44 no.4
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• pp.337-342
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• 2000

Many kinds of experiments were performed for the quality control of antifoaming agents used in thermal power pIants of KEPCO. We tried to establish more convenient ans more accurate quantitative analytical method to determine the amount of silicone oil in silicone oil type antifoaming agent regardless of the amount and/or the type of involved surface active agents. First, the amount of silicone oil was measured by gravimetric method or centrifugal method using very simple apparatus, and then was compared to the results of FT-lR spectroscopy. The centrifugal method was turned out a poor method depending upon the recovery test and virtual experiments. Some antifoaming agents showed very similar results between gravimetric method and spectroscopic methods, and the others gave very different results. We concluded that FT-lR spectroscopy is the most convenient and reliable methodto determine the amounts of silicone oil in the antifoaming agents.

• Membrane Journal
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• v.19 no.4
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• pp.341-347
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• 2009

Nanohybrid based on environmentally friendly and biodegradable polymer, poly propylene carbonate (PPC) and cloisite 20B (PPC/C-20B) have been synthesized by solution blending method and their morphology, thermal and water absorption properties have been evaluated. The structure of PPC/C-20B nanohybrid was confirmed by X-ray diffraction (XRD). The thermal property of PPC and PPC/C-20B nanohybrid were investigated by thermal gravimetric analysis (TGA) and differential scanning calorimetric (DSC). The experimental results demonstrated that nanohybrid showed the highest thermal stability in TGA and DSC. TGA tests revealed that the thermal decomposition temperature ($T_{d50%}$) of the nanohybrid increased significantly, being $23^{\circ}C$ higher than that of pure PPC while DSC measurements indicated that the introduction of 5 mass% of clay increased the glass transition temperature from 21 to $30^{\circ}C$. Further the water absorption capacity of the PPC was significantly decreased by the incorporation of clay. Water absorption cause degradation of the coating by the moistures and affect the physical and mechanical performance. This result indicates that organic modifiers have effect on thermal and water absorption capacity of PPC and are of importance for the practical process and application of PPC.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.207-208
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• 2007

Recently, high performance microelectronic devices are designed in multi-layer structure in order to make dense wiring of metal conductors in compact size. Imprint lithography have received significant attention due to an alternative technology for photolithography on such devices. In this work, we synthesized dielectric composite materials based on epoxy resin, and investigated their thermal stabilities and dynamic mechanical properties for thermal imprint lithography. In order to enhance the mechanical properties and toughness of dielectric material, various modified polyetherimide(PEI) was applied in the resin system. Curing behaviours, thermal stabilities, and dynamic mechanical properties of the dielectric materials cured with various conditions were studied using dynamic differential scanning calorimetry (DSC), thermo gravimetric analysis (TGA), and Universal Test Method (INSTRON).

• Nuclear Engineering and Technology
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• v.48 no.2
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• pp.299-303
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• 2016

Prompt gamma activation analysis using a thermal neutron-guided beam at Japan Atomic Energy Agency JRR-3M was applied for the precise determination of Si in silicon nitride ceramic reference materials [Japan Ceramic Reference Material (JCRM) R 003]. In this study, the standard addition method coupled with internal standard was used for the nondestructive determination of Si in the sample. Cadmium was used as internal standard to obtain the linear calibration curves and to compensate for the neutron beam variability. The analytical result of determining Si in JCRM R 003 silicon nitride fine powder ceramic reference materials using prompt gamma activation analysis was in good agreement with that obtained by classical gravimetric analysis. The relative expanded measurement uncertainty (k = 2) associated with the determined value was 2.4%.

• Journal of Environmental Science International
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• v.13 no.4
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• pp.429-434
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• 2004

The purpose of this study was to investigate the possibility of application of microwave energy for the fabrication of polymer/clay nanocomposite. APES/Clay nanocomposites were prepared at 13$0^{\circ}C$ for 30min with various content of clay by melt-intercalation method under classical and microwave heating source. APES/Clay samples were characterized by the means of X-ray diffractometry(XRD), thermal gravimetric analysis(TGA), and rheometric dynamic analysis(RDA). It was found that intercalated or exfoliated state was obtained in the samples according to the condition of organic modification, clay content, and heating source.