• Proceedings of the Korean Environmental Sciences Society Conference
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• 2002.05b
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• pp.135-136
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• 2002

수지 및 실란트의 제조 과정에서 불양의 원인이 되는 수분을 흡습하기 위하기 위하여 첨가하는 ？ CaO는 분진 공해가 발생하며 제품의 불량의 원인이 된다. 이러한 단점을 개선하기 위하여 CaO의 함량이 80% 이상인 에멀젼의 제조할 때 용매는 DOP, 분산제는 습윤성과 분산성이 우수한 카프복실산 에스테르 종류의 계면활성제를 사용하였고, 이어서 분자량이 큰 응집 방지제를 첨가하여 습기 제거제 에멀젼을 완성하였다. 이후에 온도에 따라서 변화하는 점도를 일정하게 유지하기 위하여 POENPE를 첨가하므로서 계절에 상관없이 사용이 가능하도록 하였다.

• THE INDUSTRY AND TECHNOLOGY OF GAS
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• v.5 no.1 s.6
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• pp.17-23
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• 2002

• 열병합발전
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• s.58
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• pp.8-13
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• 2007

• Korean Journal of Materials Research
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• v.3 no.1
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• pp.84-94
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• 1993

This paper deals with the fatigue properties of chopped strand glass mat/polyester composite to understand the effect of water absorption on fatigue behavior of GFRP. The fatigue crack in the both no water and a water absorption materials initiated at the initial of cycle. Thereafter, it was divided with two regions that one decreased with the crack extension and the other increased with the crack extension. The absorption of distilled water degrades the bond strength between fiber and matrix, there, by the tendency of fiber pull-out is increased in perpendicular to crack growth deirection and the debonding of fibers increased to the place which is parallel to crack growth direction. Therefore, the reduction of fatigue strength was caused by these factors.

• Journal of the East Asian Society of Dietary Life
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• v.11 no.6
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• pp.479-484
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• 2001

The absorption characteristics of persimmon powder related to different drying methods and various storage temperatures was investigated. The physical properties of persimmon powder by different drying methods displayed the largest amount of porosity in the freeze-dried sample, and the smallest in hot air dried sample. Equilibrium moisture was reached in 6 days. Monolayer moisture contents were predicted to 0.09687~0.19712(freeze drying), 0.07820~0.18617(vacuum drying) and 0.07715~0.18056(hot air drying) g H2O/g solid respectively using the BET equation. BET equation for isothermal absorption curve showed over 0.95 R-square for all dried methods. Monolayer moisture contents were increased as storage temperature was incremented because water molecular movement was more active and there was a greater chance to clash with the absorption surface area.

• Korean Journal of Food Science and Technology
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• v.19 no.2
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• pp.176-180
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• 1987

The sorption characteristics of dried garlic flakes stored at various relative humidity and storage temperature were studied. At low relative humidity below RH 51%, the sorption equilibrium was easily attained, whereas at higher relative humidity above RH 67%, the flakes were browned by higher equilibrium moisture content. The flakes were browned at relative humidity above 67% at $20^{\circ}C$ and $35^{\circ}C$, above 84% at $5^{\circ}C$, respectively. The moisture contents of monolayer value for the flakes were ranging from 5.80% to 6.20% (DB) with varying temperatures. And the necessity of moisture-proof packaging material suggested for the long term storage of the flakes because the lower moisture content and storage temperature, the higher driving force of wetting. Regression equation for browning rate prediction with relative humidity and storage temperature of the flakes was determined.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.399-404
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• 1988

The sorption characteristics of garlic powder stored at various relative humidities and storage temperatures were studied. At lower relative humidity below RH 51%, the sorption equilibrium was easily attained, whereas at higher relative humidity above RH 67%, the powders were browned by higher equilibrium moisture content. The powders were browned at relative humidity above 67% at $20^{\circ}C\;and\;35^{\circ}C,\;above\;84%\;at\;5^{\circ}C$, respectively. The moisture contents of monolayer value for the powder were ranged from 5.53%(DB) to 5.92% (DB) with varying temperatures. And the necessity of moistureproof packaging material suggested for the long term storage of the powder because the lower moisture content and storage temperature, the higher driving force of wetting.

• Korean Journal of Food Science and Technology
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• v.15 no.4
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• pp.315-320
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• 1983

The water vapor sorption isotherms for a great variety of agricultural products were determined by using the standard salt solution technique at the temperatures of $25^{\circ},\;35^{\circ}\;and\;45^{\circ}C$. The B.E.T. monomolecular layer moisture contents were evaluated from experimental data on the sorption isotherms, and an analysis was made of the thermodynamic functions for water vapor sorption behaviors with respect to the storage stability of dehydrated foods. It may be concluded that the variation of entropy with moisture content of some agricultural products and seaweeds investigated would be a guide for the elucidation of the storage stability of dehydrated foods.

• Composites Research
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• v.21 no.2
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• pp.8-14
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• 2008

Decrease of strength in composite material is generally caused by water absorption. It makes fracture of material, and loss of money or human lives. The objective of this study is to investigate the causes of decrease in strength by water absorption. Mechanism of water absorption was supposed as three steps. This mechanism is consisted of absorption into resin, absorption between resin and surface treatment agent, and delamination between fiber and resin. Conditions of test were supplied differently; kinds of fiber and resin, immersion time etc. Both of reversible reaction and irreversible reaction occurred simultaneously. Most of decrease in strength was finished at 2.5% water absorption, and the strength was recovered. At 4% water absorption, most of decrease was caused by irreversible reaction, therefore, there was a tendency not to be recovered in strength.

• Korean Journal of Food Science and Technology
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• v.21 no.3
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• pp.360-363
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• 1989

The initial moisture adsorption of soybeans was examined under the conditions : RH, 57-86% ; temperature, $16^{\circ}-34^{\circ}C$, and storage time, 100 hours. The changes in moisture content as a function of time held a relation: log dw/dt=b log t + log a, where w is the moisture content (%, db), t is time (hour) and a and b are the parameters which were calculated from the experimental data. The calculated moisture content from the equation agreed well with the measured moisture content. The activation energy of initial adsorption rate was about 15500cal/g-mole in all soybeans. The initial adsorption rate at temperature $16^{\circ}-28^{\circ}C$ could be estimated from a following equation : log(log dw/dt)=-15500/2.303RT.