• Journal of the Korean Ceramic Society
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• v.16 no.1
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• pp.21-25
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• 1979

This study is proposed to find an appropriate body for high expansion glass ceramics of ${Na}_2O-{Al}_2O_3-{SiO}_2$ system. The compositions of basic glasses are selected to be melted easily and to be crystallized into nepheline with various contents of alumina. The crystallization temperatures of basic glasses are determined by DTA. The crystals in the basic glasses developed by heat treatment are investigated by X-ray diffraction analysis, and thermal properties such as expansion coefficients, fusion points are measured. We find, therefore,that crystallization temperatures, crystal phases and thermal properties are affected by content of alumina.

• Proceedings of the Korean Magnestics Society Conference
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• 2010.06a
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• pp.108-109
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• 2010

In summary, the FMR technique was applied to investigate the magnetic properties of Py thin films. Frequency dependence of the resonance field and line width was analyzed using Landau-Lifshitz-Gilbert equation.

• Macromolecular Research
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• v.13 no.6
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• pp.553-556
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• 2005

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1572-1575
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• 2005

Poly(vinyl phenol)(PVP)/$TiO_2$ nanocomposite the films have been prepared incorporating metal alkoxide with vinyl polymer to obtain high dielectric constant gate insulating material for a organic thin film transistor. The surface composition, the morphology, and the thermal and electrical properties of the hybrid nanocomposite films were observed by ESCA, scanning electron microscopy (SEM), atomic force microscopy(AFM), and thermogravimetric analysis (TGA). Thin hybrid films exhibit much higher dielectric constants (7.79 at 40wt% metal alkoxide).

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.3
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• pp.80-87
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• 2011

This research was performed to investigate the physical and mechanical properties of Chanhoji manufactured with the traditional method. This research would provide a basic information for its application in the manufacture of Korean-style house. A piece of Changhoji was manufactured to have a weight of 3.75 g. The weight was increased with the basic weight and no increase was not found on its density. The strength properties of Changhoji are superior to a copying paper, and the quality showed the first grade in Korean Standard (KS M 7301). The air resistance varied with the thickness from 2 to 19 seconds, but it showed better performance than a copying paper having 38 seconds. This research would be used for the practical use in understanding the ventilation and lightening properties of windows and doors in Korean-style house.

• Proceedings of the Korean Vacuum Society Conference
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• 2002.06a
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• pp.37-37
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• 2002

• Macromolecular Research
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• v.15 no.5
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• pp.473-477
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• 2007

• Bulletin of the Korean Chemical Society
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• v.30 no.9
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• pp.2057-2060
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• 2009

Conducting poly-N-isopropylacrylamide-N-vinyl carbazole (PNI-nvc) copolymers were synthesized via in situ deposition technique by dissolving different weight percentages of N-vinyl carbazole (10, 20, 30, and 40%). The structural morphology and FT-IR studies support the interaction between PNI and N-vinyl carbazole. The temperaturedependent DC conductivity of PNI-nvc was studied within the range of 300 ${\leq}\;T\;{\leq}$ 500 K, presenting evidence for the transport properties of PNI-nvc. The DC conductivity of PNI-nvc copolymers signifies the future development of new nanocopolymers that acts as a multifunctional material.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2001.02a
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• pp.41-44
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• 2001

Mechanical test of the Carbon Fiber Reinforced Plastics (CFRP) composite specimen was performed based on the ASTM code at the ambient and low temperature. Tension, compression in-plane shear, and inter-laminar shear properties of the composite laminates were evaluated experimentally using the Universal Testing Machine(UTM) system at the temperature of $24^{\circ}C$,$-76^{\circ}C$ , and $-196^{\circ}C$. From the test results it was found that the CFRP chosen for the Korea Superconducting Tokamak Advanced Research(KSTAR) magnet supporting post had smaller tensile strength and larger compressive strength at the low temperature than those of the ambient temperature because of material ductility.

• 한국정보디스플레이학회:학술대회논문집
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• 2001.08a
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• pp.209-212
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• 2001

We report the synthesis and characterization of new alkoxy substituted spirobifluorene derivatives. The spiro compounds having alkoxy hydrocarbon chains were readily soluble in common organic solvents, having improved film-forming properties and had a significantly reduced tendency to crystallize, resulting in increasing their service lifetime. The results of DSC showed that it was amorphous. The optical and electroluminescent spectra were characterized. Electroluminescence (EL) properties of three-layer light emitting diodes (LED) of $ITO/TPD/spirobifluorene/Alq_3/LiF/Al$ as the active layer were characterized. Blue emission peaking of the EL spectrum of the three-layer device at 402 nm and a luminance of 3,125 $cd/m^2$ were achieved at a drive voltage 12.8 V. The luminous efficiency was obtained to be 1.7 lm/W. The color coordinate in CIE chromaticity is (0.16, 0.09), which is in a pure blue region. The external quantum efficiency was obtained to be 2.0%. The results indicate that the spirobifluorene compounds having alkoxy hydrocarbon chains are strongly potential blue emitters for LED applications.