• Journal of Conservation Science
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• v.32 no.2
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• pp.249-259
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• 2016

Effect of the flame retardants on Dancheong is studied in the present work. Two kinds of flame retardants were applied on Dancheong specimens and compared with control groups on which distilled water was applied instead of the flame retardants. The flame retardants enhanced the hygroscopic property of the surface of Dancheong. Furthermore, the added flame retardants reacted with oyster shell white($CaCO_3$) and lead red($Pb_3O_4$), producing new chemical compounds like Calcium phosphate tribasic and Lead Phosphates which make the painted layer of Dancheong dissolving and whitening over certain period of time. When applied in excessive amount and exposed in repetitive wet and dry condition, especially, they aggravate the surface problems significantly. These results will provide a good reference on the study of the discoloring/whitening effect of Dancheong layers at many traditional wooden building in Korea.

• Applied Biological Chemistry
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• v.28 no.2
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• pp.51-55
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• 1985

Dried black soybeans were soaked in water at the temperature range of $4^{\circ}C{\sim}100^{\circ}C$ and in salt or sugar solution at $100^{\circ}C$ in order to investigate their effects on the cooking ratio and diffusion property of color pigments. As the temperature increased, the equilibrated absorbance at 490nm of soaking water after 120min was linearly increased. The activation energy for diffusion of color pigments were found to be 4.23 Kcal/mole at the range of $60^{\circ}C{\sim}100^{\circ}C$ and 8.31 kca1/mo1e at $4^{\circ}C{\sim}60^{\circ}C$. The cooking ratio, % cooked beans after heating, of black soybeans were more affected by the salt concentration that of sugar. Both concentrations reduced the cooking ratio as they increased. The sorption isotherm of Kongjaban showed a quite different curves between the storage at $4^{\circ}C$ and $25^{\circ}C$. The sorption and desorption rates during storage could be represented by the equation of $log({\frac{dw}{dt}}{\times}10^3))=alogt+logb$ with a very high correlation.

• 전기의세계
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• v.20 no.2
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• pp.27-31
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• 1971

Using insulating paper (cellophan), we measured the influences of moisture abosrbed for electrical properties i.e. V.I curves which result in deteriorating due to the moisture alsorbed is related to electrical properties Considerally due to the electrolytic effects of moisture involved cellulose Gel structure, we obtained also an evaluation method of deterioration rate Caused by the moisture absorbed in insulating papers.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.705-708
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• 2008

Diatomite, bentonite and zeolite were used as porous materials for fabricating hygroscopic panels. Moisture adsorption and desorption of porous materials were investigated and hydrothermal method was applied to fabricate panels. Cheolwon diatomite and Pohang zeolite showed excellent characteristics of moisture adsorption and desorption. These characteristics were caused by higher surface area and pore volume of porous materials. Moisture adsorption contents were influenced by surface area and pore volume of panels, and surface area more effected on moisture adsorption. Moisture adsorption content of panel with 10% Pohang zeolite was 180g/m$^2$and that of 10% Cheolwon diatomite was 170g/m$^2$. Moisture desorption content of panel with 10% Pohang zeolite was 105g/m$^2$. Moisture adsorption contents of panel with porous materials were higher than that of panel without porous materials.

• Korean Journal of Food Science and Technology
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• v.16 no.1
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• pp.108-112
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• 1984

The sorption characteristics of red pepper powder stored at various relative humidity and temperature were studied. At low relative humidity below RH 57%, the sorption equilibrium was easily attained, whereas at higher relative humidity above RH 75%, the powder was browned by higher equilibrium moisture content. The moisture content of monolayer value for the powder was ranging from 11.32% to 12.13% with temperature. First order regression equation of equilibrium moisture content for relative humidity was determined.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.164-170
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• 1999

Cracking of rice caused by moisture migration during storage under different relative humidity conditions was investigated for the establishment of safe storage condition of rice. Rice was cracked when a large difference in equilibrium relative humidity $({\Delta}ERH)$ between the rice and the environment was present. External and internal cracks were generated as the results of moisture desorption and adsorption, respectively. The external cracks by moisture desorption generated in all directions and shaped irregularly, while the internal cracks by moisture adsorption did in radial direction and showed a typical shape. The cracking trend could be analyzed by the Weibull function, and the cracking constant increased with ${\Delta}ERH$. The frequency of cracked rice increased linearly with In $({\Delta}ERH)$. The critical crack-inducing ${\Delta}ERH$ was $11.3{\sim}16.4%$ during desorption and $10.8{\sim}17.1%$ during adsorption. A diagram for the safe storage of rice was developed with respect to the initial moisture content and the water activity of rice.

• Korean Journal of Food Science and Technology
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• v.16 no.4
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• pp.437-442
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• 1984

The color changes and sorption characteristics of dried whole red pepper stored at various relative humidity and temperature were studied. Dried whole red pepper was browned at relative humidity above 67%, and was molded at relative humidity above 84%, and was decolorated at relative humidity below 32%. Therefore, about 50% RH condition was suitable for the preservation of dried whole red pepper and the safe moisture content levels for storge to prevent decolorization were ranging from 15.65% to 19.62% dry basis (DB) with varying temperatures. The moisture contents of monolayer value for the dried whole red pepper were ranging from 7.52% to 9.23% (DB) with varying temperatures. The third order regression equation for the equilibrium moisture content prediction with relative humidity was determined.

• Composites Research
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• v.34 no.3
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• pp.174-179
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• 2021

Currently, fluid transfer steel pipes take a lot of time and expense to maintain all facilities due to new construction and painting or corrosion and aging. Therefore, this study was conducted for designing a CFRP pipe structure with high corrosion resistance and chemical resistance as a substitute for steel pipes. The helical/hoop pattern was cross-laminated to improve durability, and HNT was added to suppress the moisture absorption phenomenon of the epoxy. The HNT/CFRP pipe was manufactured by a filament winding process, and performed a mechanical property test, and a moisture absorption test in distilled water at 70℃. As a result, the highest bending strength was obtained when the hoop pattern was laminated with a thickness equivalent to 0.6% of the pipe. The 0.5 wt% HNT specimen had the highest moisture absorption resistance. Also, the delamination phenomenon at the interlayer interface was delayed, resulting in the lowest strength reduction rate.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.35T no.2
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• pp.1-5
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• 1998

$CaSnO_3$ specimens were fabricated by solid reaction method, and their humidity sensitive characteristics have been investigated. Capacitance increases with increasing relative humidity, better humidity sensitivity are shown at lower frequencies. Humidity sensitivity are stable at variable temperatures, and hysteresis phenomenon is shown with adsorption and desorption. Drift phenomenon is exhibited by exposing the specimens in the air, and a decrease of humidity sensitive by contamination is inhibited by heat cleaning.

• Proceedings of the KIEE Conference
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• 1997.07e
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• pp.1743-1745
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• 1997

본 논문은 전력케이블의 열화진단을 위한 기초연구로서 6.6kV XLPE 케이블에 직류전압을 인가한 후에 절연 저항, 직류 누설 전류, 잔류 전압 비율, 킥 현상, 성극 지수 등을 각각 측정하였다. 본 논문은 전력케이블의 열화 현상을 파악하고, 예방진단을 위한 기초적인 Data를 얻기 위하여 직류 누설 전류의 특성을 파악하였다. Virgin케이블에 있어서 절연성능은 절연 저항의 특성은 거의 $\infty$를 나타내지만 잔류 전압의 특성은 케이블의 길이와 인가되는 전압에 따라서 큰 변화를 나타내고 있다. 이같은 잔류 전압의 특성은 케이블내의 공간전하의 형성과 크기에 따라서 의존되는 것으로 판단되며, 반면에 측정의 분위기에 많은 영향을 받는다. 이와같은 측정결과를 기초로 하여 계속적으로 Virgin케이블을 흡습시키면서 각 절연특성의 변화를 평가할 계획에 있다.