• Proceedings of the KAIS Fall Conference
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• 2002.05a
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• pp.124-126
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• 2002

폴리우레탄의 특징을 이용하여 폴리우레탄에 흡습능력 과 탈취능력을 향상시키고 향의 서방성 능력을 첨가하여 장루 환자들이 사용하기에 적합한 패드의 특징을 테스트 후 분석하였다. 수분의 흡습능력, 변의 냄새제거 정도의 탈취 능력 , 향의 지속성을 측정하였다. 폴리우레탄만의 특징으로도 흡습능력과 탈취능력이 있지만 주흡습제 보조흡수제를 첨가하고, 소취 제와 보조제를 첨가하여 더욱 개선된 흡습능력과 탈취능력을 확인하였다.

• 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.22 no.5
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• pp.530-532
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• 1990

The moisture sorption behaviors of dry corn(DC). dry-corn (DCC) and soaked-rooked corn(SCC) at $25^{\circ}C$ were analyzed. The corn was soaked in water at $26^{\circ}C$ for 8hr. The cooking times for DCC and SCC were 30 and 20min. respectively, at $80^{\circ}C$. Desorption occurred for DC and DCC at RH below 23% and SCC at RH below 33% during storage. Moldiness was observed in all samples at RH 97%, after 192hr for DC and 288 hr for both DCC and SCC. At the same water activity. SCC sample had the highest moisture content, followed by DC. The SCC sample had the highest monolaver value and sorption heat. Stability isotherms indicated that DC and SCC had better storability than DCC.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.128-137
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• 1999

In this study, shiitake mushrooms were dried by hot air, vacuum and freeze drying methods and theire physical properties were compared. Since the pore size affects the amount of absorption, the characteristics of water sorption were investigated at various humidities and temperatures. Results showed that the freeze dried product had the greatest pore area and the highest absorption capacity. However, all the dried samples showed similar quality. The browning degrees were severely changed with increased relative humidities and temperatures. Among these drying methods, the freeze drying gave the greatest change in browning degree. The GAB monolayer moisture contents of the dried shiitake mushroom were $5.3{\sim}7.7%$. The prediction model was also provided using parameters such as relative humidity, temperature and pore area.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.4
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• pp.476-483
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• 1993

The moisture sorption characteristics of commercially produced seasoned dried layer (Porphyra yezoensis) was investigated by measuring sorption isotherms. The laver and two kinds of desiccant (silica gel and zeolite based desiccant) were used at temperatures of 30, 40 and 5$0^{\circ}C$ respectively using the method of saturated salt solution. Time to reach the equilibrium moisture content at each temperature and relative humidity varied from 4~6hr for the laver to 20~25hr for the silica gel and 43~46hr for the zeolite. The isotherms of the layer and the desiccants showed the characteristic sigmoidal curve. Monomolecular layer moisture content calculated using the BET equation at each temperature (30, 40, 5$0^{\circ}C$) were 5.26, 4.46 and 3.49% (d.b.) for the laver, 17.32, 15.24 and 12.89% (d.b.) for the silica gel, 16.89, 14.92 and 14.44% (d.b.) for the zeolite, respectively, Both desiccants showed higher values of the monomolecular layer moisture content than the laver. In all cases, the monomolerular layer moisture contents were decreased linearly as the temperature was increased in the experimental ranges. Water vapor transmission rate of the packaged material was also influenced by the temperature, which could be explained by the Arrhenius equation.

• 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.