• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.39 no.12
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• pp.68-75
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• 2010

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.451-456
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• 2012

This study was carried out to evaluate thermal performance of the renewable hybrid heat supply system with solar thermal system and wood pellet boiler for Zero Carbon Green home of apartment houses. The hybrid heat supply system was set up at Korea Institute Energy Research in 2011. The system was comprised of the wood pellet boiler unit with heat capacity designed as 20,000 kacal/hr, a evacuated tubular solar collector 3.74 $m^2$ of aperture area at the $20^{\circ}$ install angle, a 0.3 $m^3$ hot water storage tank, a 0.15 $m^3$ hot water storage tank for space heating. Thermal performance tests for one-house of apartment house were carried out by hot water load and heating load in winter season through the hybrid heat supply system. As a result, hot water energy supplied by the hybrid heat supply system was 11kWh in a day. Solar thermal energy portion was 2.99kWh which is 27% of the total hot water energy supply. wood pellet boiler supply portion was 8.017kWh which is 73% of the total hot water energy supply.

• Journal of Korea Far Infrared Association
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• s.19
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• pp.53-62
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• 2003

• Journal of the Korean Solar Energy Society
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• v.32 no.6
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• pp.53-59
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• 2012

This study was carried out to evaluate thermal performance of the renewable hybrid heat supply system with solar thermal system and wood pellet boiler for Zero Carbon Green home of apartment houses. The hybrid heat supply system was set up at Korea Institute Energy Research in 2011. The system was comprised of the wood pellet boiler unit with heat capacity designed as 20,000kcal/hr, a $0.15m^3$ hot water storage tank for space heating, a evacuated tubular solar collector $3.74m^2$ of aperture area at the $20^{\circ}$ install angle, a $0.3m^3$ hot water storage tank. Thermal performance tests for one-house of apartment house were carried out by hot water load and heating load in winter season through the hybrid heat supply system. As a result, hot water energy supplied by the hybrid heat supply system was 11kWh in a day. Solar thermal energy portion was 2.99kWh which is 27% of the total hot water energy supply. wood pellet boiler supply portion was 8.017kWh which is 73% of the total hot water energy supply.

• Journal of the Korean Solar Energy Society
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• v.40 no.2
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• pp.25-36
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• 2020

The Korean government has a plan to mandate zero-energy buildings in 2020 for public and 2025 for private buildings. In order to design a zero-energy building, insulation and airtightness, which are the most basic elements of passive house technology, are required, and the government has been accomplished this through step-by-step strengthening of related standards. In passive house with high thermal insulation and airtightness performance, the heat introduced into the building through solar radiation can be stored for a long time to keep the inside warm during winter. On the other hand, during summer, heat introduced into the building cannot be easily released to outside, so it is necessary to actively block solar radiation and high temperature outdoor air to prevent an increase of indoor temperature. Therefore, this study aims to derive an appropriate operation condition of passive house to maintain the indoor temperature at an suitable level according to the ventilation methods and solar shading conditions. As a result, under the conditions that the outdoor temperature was 28℃ or less, the ventilation using a heat recovery ventilation system at daytime and natural ventilation at nighttime were selected for the most appropriate operation method. In addition, in the case of solar shading, it was found that blocking solar radiation at daytime using the blind and open the blind at nighttime to ensure natural ventilation were selected for the most appropriate solar shading condition.

• Korean Chemical Engineering Research
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• v.48 no.2
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• pp.212-217
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• 2010

In this study, suspension polymerized toners were prepared by using poly(vinyl alcohol)(PVA) as an organic suspending agent. Styrene and butylacrylate monomers were used simultaneously with carbon black to prepare microspherical polymerized toners with a narrow-particle size distribution. Preliminary particles without carbon black were polymerized first to optimize suspension polymerization conditions. The preliminary particles were prepared at various polymerization conditions and their characteristics were compared to each other to determine an optimized polymerization condition. The black polymerized toner prepared at the optimized polymerization condition showed reasonable particle size and shape, and good thermal and printing characteristics by showing its glass transition temperature at $53.6^{\circ}C$.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.1
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• pp.15-21
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• 2008

SiC has an excellent resistance to oxidation and corrosion, high temperature strength and good thermal conductivity. However, it is difficult to density because of its highly covalent bonding characteristics. Hot-press sintering process was applied to fabricate fully densified SiC ceramics with carbon and boron addition as a sintering additive. The addition of carbon improved the mechanical properties of SiC because it could induce a fine and homogeneous microstructure by the suppression of abnormal growth of SiC grain. Also, the addition of carbon could control the phase transformation of SiC. The phase transformation of 6H to 4H increased with sintering temperature but the addition of carbon decreased that kind of phase transformation.

• Elastomers and Composites
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• v.46 no.3
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• pp.237-244
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• 2011

Five natural rubber (NR) composites with different reinforcing systems of unfilled, carbon black, carbon black with silane coupling agent, silica, and silica with silane coupling agent were thermally aged and change of the crosslink densities by the accelerated thermal aging was investigated. The crosslink densities on the whole increased as the aging time elapsed irrespective of the reinforcing systems. The crosslink density changes became noticeable by increasing the aging temperature. For carbon black-filled composites, the silane coupling agent made the crosslink density change to be increased. For silica-filled composites, however, the silane coupling agent made the crosslink density increment reduced at 60 and $70^{\circ}C$ and it hardly affect the degree of the crosslink density change at 80 and $90^{\circ}C$. The activation energies for the crosslink density changes of the carbon black-filled samples increased continuously in a logarithmic fashion, whereas that of the silica-filled one showed a quasi-steady state ranges at aging times of 30-150 days. The activation energy of the unfilled sample increased exponentially with the aging time. The experimental results were explained with sulfur donation from the silane coupling agent, surface modification of the filler by the silane coupling agent, adsorption of curative residues on the silica surface, and release of the adsorbed curative residues.

• Korean Chemical Engineering Research
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• v.48 no.5
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• pp.638-642
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• 2010

In order to develope anti - static polyester resin which may be employed to dangerous circumstance with high organic vapor content, the effect of anti - static agents on the surface resistance and tensile strength of polyester resin were studied. Three organic anti - static agents and a conductive carbon black were adapted and used separately and together. The effects of anti - static agents, their contents, and synergic effect of anti - static agents were experimentally examined. Surface resistance and tensile strength of the polyester resin were decreased with the content of anti - static agents, and polyester resin with low surface resistance and relatively high tensile strength could be prepared by synergic effect of organic anti - static agent and carbon black.

• Journal of the Korean Electrochemical Society
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• v.24 no.4
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• pp.113-119
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• 2021

In this study, impurity free V^3.5+ electrolytes were prepared using formic acid as a reducing agent and PtD/C as a catalyst and it was applied to VRFB. The well-oriented 3D dendrite structure of the PtD/C catalyst showed high catalytic activity in formic acid oxidation reaction and vanadium reduction reaction. As a result, the conversion ratio of electrolyte using the PtD/C was 2.73 mol g^-1 h^-1, which was higher than that of 1.67 mol g^-1 h^-1 of Pt/C prepared by the polyol method. In addition, in the VRFB charging and discharging experiment, the V^3.5+ electrolyte produced by the catalytic reaction showed the same performance as the standard V^3.5+ electrolyte prepared by the electrolytic method, thus proving that it can be used as an electrolyte for VRFB.