• Preventive Nutrition and Food Science
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• v.8 no.3
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• pp.230-234
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• 2003

Mass transfer characteristics during osmotic dehydration of carrots were studied as functions of immersion temperature and time, and sugar and salt concentrations. The effect of osmotic dehydration on the degree of browning of air-dried carrots was also evaluated. Increasing the immersion temperature and time, sugar concentration, and salt addition increased water loss, sugar gain, molality and rate of dehydration. The water loss and increases in solids, and molality were rapid in the beginning of the process and then increased slowly during remainder of the process. Increasing 1 or 2% salt concentration in the 40$^{\circ}$Brix sugar solution at 6$0^{\circ}C$ increased water loss and solid gain. Salt addition was not able to significantly affected on water loss and solid gain compare to temperature (40～8$0^{\circ}C$) and sugar concentration (20～60$^{\circ}$Brix) changes due to the low salt concentration. A minimum degree of browning of the air-dried carrots (O.D. = 0.048) could be achieved using binary solutions (40$^{\circ}$Brix sugar solution with 2% salt addition) with 24 min of immersion time compared to control (O.D. = 1.308) or blanching with 24 min of immersion time (O.D. = 0.174).

• Food Science of Animal Resources
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• v.34 no.1
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• pp.115-121
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• 2014

This study explored the effects of water or brine (2% NaCl, w/v) immersion thawing combined with ultrasound treatment (40 kHz, 150 W) on the quality characteristics of pork. Ultrasound treatment of pork was conducted in two cold media (at $4^{\circ}C$), water and 2% (w/v) brine, respectively. Because the ultrasound treatment caused temperature increase in the media from $4^{\circ}C$ to $16^{\circ}C$, the qualities of pork thawed by ultrasound were compared with those thawed by immersion either in water or brine where the temperature was being maintained at either $4^{\circ}C$ (low temperature control) or $17^{\circ}C$ (high temperature control). The ultrasound treatment resulted in rapid thawing of pork where the thawing rate was similar to those thawed in the $17^{\circ}C$ media. For quality characteristics, ultrasound-treated pork in brine had an advantage of less cooking losses when comparing to the control. In particular, ultrasound treatment in brine exhibited the lowest shear force (or highest tenderness) among the freezing/thawing treatments. Although the ultrasound processing in brine caused discoloration of the pork, this thawing technique had potential to be applied as a commercial thawing technology for frozen foods.

• Journal of Ocean Engineering and Technology
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• v.13 no.4 s.35
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• pp.63-74
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• 1999

This study has been investigated about the influence of moisture environment on the mechanical properties in the carbon fiber cross laminates. And it has been also investigated the effect of unit ply thickness of the carbon fiber cross laminates on the mechanical properties in distilled water of $80^{\circ}C$ for a certain period of time. As a results, it was found that the weight gain of water was increased with the immersion time and the bending strength and fracture toughness were decreased with the weight gain of water. And it was also shown that the bending strength and fracture toughness were decreased with the increasing of the unit ply thickness of carbon fiber cross laminates through the immersion time.

• The Korean Journal of Physiology
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• v.3 no.1
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• pp.59-66
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• 1969

Experiments on thermoregulatory responses to cold immersion stimulus were carried out in September, 1968 (summer studies) and February, 1969 (winter studies). Eight each of ama and control subject were selected at random from a same community in Yong-Do Island, Pusan. The results obtained are summarized as follows: 1) The rate of fall in muscle temperature of forearm during a 30 min-immersion in $6^{\circ}C$ water bath was significantly slower in the ama in winter and was about the same in the two groups in summer. However, the magnitude of change in the skin temperature and the heat fluxes observed during immersion period was not significantly different either between groups or between seasons. 2) Both finger blood flow and skin temperature during one hr-immersion in $6^{\circ}C$ water bath decreased significantly in the ama as compared to the control. The magnitude of cold-induced vasodilatation during immersion period was significantly greater in the control in winter. However, the time of onset and blood flow at onset showed no significant relation between groups. 3) The magnitude of reactive hyperemia after a 5 min-arterial occlusion in both air and $15^{\circ}C$ water bath was significantly lower in the ana than in the control. In control subjects, post-occluded blood flow in water was significantly greater than in air, while in the ama it decreased to 1/2 of control values. The time required for the return of blood flow to resting values in the air was faster in the ama than in the control but was the same in water in the two groups. 4) The results suggest that vasoconstrictor tone increased in the ama in winter, indicating the development of vascular adaptation as a part of cold acclimatization.

• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.497-502
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• 1990

The effect of sugar concentration, immersion time and temperature on water loss, solid gain or loss, and sugar molality of potatoes during osmotic concentration was analyzed by a response surface methodology (RSM), and those values were predicted by using a second degree polynomial regression model. Effect of osmotic concentration and blanching on vitamin C retention of air dried potatoes (6% MC: wet basis) was also evaluated. The most significant factor was sugar concentration for water loss, solid gain or loss, sugar molality, rate parameter and retention of vitamin C. Second and third factors were immersion time and temperature respectively. Water loss and solid gain were rapid in the first 10 min and then levelled off. A 44.6% of water loss was observed during osmotic concentration using a sugar solution $(60\;Brix,\;80^{\circ}C$) with 20 min of immersion time. Dried potatoes after osmotic concentration had higher vitamin C content than dried potatoes after blanching. Optimum regions for osmotic concentration process of potatoes were $60-70^{\circ}C$ of immersion temperature, 60 Brix of sugar solution and 16-20 min of immersion time based on above 30% of water loss and 50% of vitamin C retention.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.28 no.5
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• pp.199-205
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• 2018

A geopolymer was produced from coal ash generated from an integrated gasification combined cycle (IGCC) plant and its water resistance was evaluated. For this purpose, the geopolymer specimens were immersed in water for 30 days to measure changes in microstructure and alkalinity of the immersion liquid. Particularly, the experiment was carried out with foaming status of the geopolymers and parameters of room temperature aging condition, and immersion time. The foamed geopolymer containing 0.1 wt% Si-sludge had pores with a diameter of 1 to 3 mm and exhibited excellent foamability. Also, the calcium-silicate-hydrate crystal phase appeared in the foamed geopolymer. In the geopolymer immersion experiment, the pH of the immersion liquid increased with time, because the un-reacted alkali activator remained was dissolved in the immersion liquid. From the pH change of the immersion liquid, it was found that geopolymer reaction in the foamed specimen was completed faster than the non-foamed specimen. Through this study, it was possible to successfully produce foamed and non-foamed geopolymers recycled from IGCC coal ash. Also the necessary data for the safe application of IGCC coal ash-based geopolymers to areas where water resistance is needed were established; for example, the process conditions for room temperature aging time, effect of foaming status, immersion time and so on.

• Journal of the Korean Geographical Society
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• v.45 no.3
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• pp.342-359
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• 2010

The Bangudae Petroglyphs locate at Bangudong, Daegok-ri, Eonyang-eup, Ulju-gun, Ulsan and was designated as the No. 285 national treasure since 1995. After the construction of Sayeon-dam in 1965, there were many controversies of the rock weathering problems by the periodic immersion for approximately a few months. The isopleths of water content on the rock are drawn and the result shows relationships between the isopleths and distribution of joints or exfoliations. The distributions of water content rates in the Petroglyphs show the downward increasing pattern. This may suggest that the rates of water content are further influenced by the duration of immersion. Also, the upper part of the Petroglyphs with dense joints shows high rates of water content. If the water content rates in rocks increase, the water absorption rates increase too, because of the increasement of coefficient of permeability and porosity. The weathering damages of the Petroglyphs in which the pores are saturated by the periodic immersion are in the critical conditions.

• Applied Biological Chemistry
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• v.49 no.2
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• pp.108-113
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• 2006

This study was conducted to analyze the acidity and turbidity changes of immersion solutions as well as changes in aerobic bacteria, E. coli, anaerobic bacteria, yeast and mold counts of mulberry leaf soybean curds during storages at $4^{\circ}C$ and $25^{\circ}C$ in different immersion solutions such as distilled water, grapefruit seed extract (300 ppm) and alkaline ionic water. The acidities of immersion solutions of distilled water, grapefruit seed extract and alkaline ionic water after 18 days of storage at $4^{\circ}C$ were 0.021, 0.008 and 0.002%, respectively. After 5 days of storage at $25^{\circ}C$ were 0.042, 0.029 and 0.009%, respectively. The turbidities of the above mentioned immersion solutions were 0.50, 0.29 and 0.21 after 18 days of storage at $4^{\circ}C$ and 0.38, 0.34 and 0.27, respectively, after 5 days of storage at $25^{\circ}C$. The acidity and turbidity changes of immersion solutions were sensitive to storage temperatures. The aerobic bacteria count of mulberry leaf soybean curds after 18 days of storage at $4^{\circ}C$ was still below $10^7\;CFU/g$, the beginning point of soybean curd putrefaction; in contrast, this value was reached within one day in distilled water at $25^{\circ}C$ and between 2 and 3 days in alkaline ionic water. Grapefruit seed extract and alkaline ionic water had a better preservative effect at $4^{\circ}C$ than at $25^{\circ}C$ storage temperature.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.4
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• pp.174-181
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• 2021

Lightweight geopolymers were fabricated by using IGCC (integrated gasification combined cycle) slag and Si sludge which are classified as general wastes (recyclable resources). Three curing methods were tried to investigate the changes in compressive strength and density according to the curing method and immersion time. Immersion period was tried up to 21 days to observe long-term performance in water. Compressive strength of the specimens cured in oven decreased abruptly with an increase in immersion time. Compressive strength of the specimen cured in autoclave was low after 3 and 7 day immersion; however, increased rapidly after 21 day immersion. On the contrary, compressive strength of the specimen cured in autoclave and oven was high but substantially decreased after 21 day immersion. Conclusively, it was speculated that oven curing is effective for the compressive strength development at early age; however, autoclave curing is more desirable for the long-term performance in water.

• Journal of Nutrition and Health
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• v.44 no.5
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• pp.378-383
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• 2011

This study examined the effect of supplementary selenium on leukocytes and heat shock protein (HSP) 70 expression in serum during half-body immersion. The subjects were male college tennis athletes. All subjects participated in two repeated experiments with a 1 week interval. During the 30 min intermittent half-body immersion, subjects were given 500 mL of water with or without selenium (100 ${\mu}g$). Blood samples were taken from the antecubital vein, and differential counts were made. Serum HSP70 protein was analyzed using a commercial ELISA kit. After half-body immersion, leukocytes and lymphocytes increased significantly but neutrophils decreased significantly in both trials (with or without selenium). Selenium supplementation, compared with placebo, decreased levels of leukocytes, neutrophils, and monocytes, but not lymphocytes, to the resting level or below 60 min after immersion. Only lymphocytes continued to increase in both trials during the recovery period. Serum HSP70 protein level did not change after immersion, but it decreased 60 min after immersion with the administration of selenium. In conclusion, supplementary selenium reduced the systemic immune response and serum HSP70 protein accumulation after half-body immersion.