• Korean Journal of Soil Science and Fertilizer
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• v.13 no.4
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• pp.115-118
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• 1981

Effect of water potential of culture solution on photosynthesis, transpiration and water uptake was investigated using polyethylene glycol 6000. 1. Even at -0.5 bar of culture solution phothosynthesis was decreased by 20% within 1 hour. Plant in control showed 3.26% loss of initial water for 13 hours suggesting very sensitive in water uptake. 2. Relation between water potential of culture solution (${\psi}$) and water uptake amount (W) 2-year root was ${\psi}=-2.890/e^{2.796W}$ indicating that permanent wilting point will be greater than -2.89 bar. 3. Transpiration considerably decreased with the decrease of water potential and thus by 23.9% at -0.5 bar after 4 hours. 4. From the above results ginseng plant appears to have high root water potential at permanent wilting point and thus very week to water stress due to drought or high salt content in soils.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5384-5393
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• 2015

We investigated the effects of milling degrees of rice on characteristics of the steamed rice and fermentation of rice koji as a raw material of cheongju. It was studied for 8 months about ratio of water absorption and koji charateristics according to milling degrees. The The more increasing rice milling, the less the protein contents of milled rice was continuously decreased and the lipid and ash contents were sharply decreased to until the milling degrees 20%, and then gradually decreased. When steeping the milled rice, higher milling degrees raised rapid water asorption and higher maximum water asorption, lower water temperature raised gradual water absorption and higher maximum absorption. The longer steeping time, the steamed rice milling degrees 40% showed significantly lower hardness and springness than others. Alcohol contents of the fermented mash with rice koji milling degrees 10% was lower with 16.3-16.9%(v/v) than other sample's 17.1-17.5% (v/v). The total acid contents showed that the milling degrees 10% indicated the lowest content(0.71-0.76%) and the milling degrees 30% indicated highest content(0.93-0.99%). Within the same milling degrees, As the steeping time increases, the total acid contents imcrease. In conclusion, the milling degrees influenced on physicochemical chatacteristics of rice and steamed rice condition.

• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.25-30
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• 1991

Chicken liver was enzymatically hydrolyzed with an alkaline protease and determined the optimal conditions of reaction temperature and time, pH and enzyme to substrate ratio(E/S ratio) for possible utilization as a protein supplementary ingredient. The functional properties of hydolysate measured were water and oil absorption capacity, emulsifying activity and viscosity and sensory properties were also evaluated. It was found that hydrolysis at $60^{\circ}C$ and pH 8.0 were most effective and the degree of hydrolysis increased with increasing E/S ratio. A decrease in water and oil absorption capacity and an increase in viscosity were found during hydrolysis. The lowest emulsifying activity and highest water absorption were measured for 1/2 hour-hydrolysate and little difference was found for those treated more than 1 hour. The sensory characteristics of odor showed no significant difference among the chicken liver hydrolysates while the brightness increased and red decreased significantly(p<0.01) as the hydrolysis proceeded.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.502-508
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• 1998

The characteristics of hydration and hot-water solublilization of milled rice during cooking were investigated using Korean rice [3 varieties of Japonica type and 3 varieties of Tongil type (Japonica-Indica breeding type)]. The water uptake rate constants of Japonica type varieties during cooking were later than those of Tongil type varieties. The contents of solubles and soluble amylose among Japonica type varieties during cooking were similar, but those among Tongil type varieties were different. At the same cooking conditions, Japonica type varieties showed higher contents and leaching rate constants of solubles as well as soluble amylose than Tongil type varieties.

• Elastomers and Composites
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• v.47 no.2
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• pp.141-147
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• 2012

Silicone resin has no water-absorbing function because it is a strong hydrophobic polymer. However, addition of super absorbent polymer gives much better absorbency than that of conventional silicone resin. In this study, we developed novel silicone materials with water-absorbing function by choosing three types of amorphous acrylic super absorbent polymers with different particle sizes, determining the mixing ratio of the three polymers and applying the mixtures into two-component type silicone material for medical purpose. The change in the mechanical properties such as tensile strength, tear strength, compressive strength and hardness was investigated by varying the particle size and content ratio of the added super absorbent polymers while preparing the silicone resins. The absorbency of the silicone resins was measured over time. Additionally, the particle shape of the super absorbent polymers as well as the distribution within the silicone resin was observed using an optical microscope.

• Applied Chemistry for Engineering
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• v.23 no.6
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• pp.624-629
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• 2012

To capture and recover carbon dioxide ($CO_2$), we impregnated honeycomb made of ceramic paper with $K_2CO_3$ and its absorption characteristics of $CO_2$ were investigated. The absorption amount of $CO_2$ on the honeycomb absorbent impregnated with $K_2CO_3$ was 13.8 wt% at a constant temperature ($70^{\circ}C$) and relative humidity (66%) condition. Because the absorption amount of $CO_2$ achieved almost the same loading ratio of $K_2CO_3$ (17.6 wt%), the absorption reaction of $CO_2$ by $K_2CO_3$ on the honeycomb absorbent seems to be going smoothly. In addition, $CO_2$ absorption breakthrough characteristics of the honeycomb absorbent were analyzed at the temperature range of $50{\sim}80^{\circ}C$, and the water vapor was fed to an absorption column before the feeding of $CO_2$ or simultaneously with $CO_2$. As a result, the absorption capacity of $CO_2$ was more enhanced using the water vapor supplying before $CO_2$ than that of simultaneous supplying. It was confirmed by temperature programmed desorption analysis that the $KHCO_3$ produced by the absorption reaction of $K_2CO_3$ and $CO_2$ is regenerated by the desorption of $CO_2$ at a temperature of about $128^{\circ}C$.

• Journal of Plant Biology
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• v.34 no.2
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• pp.151-158
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• 1991

A new technique involving gamma-spectrometry was used to determine the effects of pollination on mineral uptake in petals, ovaries and leaves of tulips and daffodils. A gamma-emitting radionu'::lide solution containing selenium-75, cesium-137, manganese-54, and zinc-65 was applied to the roots of tulips and daffodils growing in water. Mineral uptake was monitored in plant parts over a 24 day period. Pollinated tulip flowers showed a rapid withdrawal of minerals from the petals and an increase in ovary mineral content, while such a source-sink relationship was not established in daffodils. In both species, the concentration of most minerals in petals and ovaries declined prior to abortion of the plant part. The roots and bulbs of the plants contained the vast majority of the labeled minerals. This study demonstrated a possibility that certain plant parts could be isolated and monitored for mineral uptake over time without destruction.uction.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.3
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• pp.119-125
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• 2013

IInsulation material is generally used for preventing heat loss from heat transport fluids, and water absorption severely reduces the insulation property. The purpose of this study is to evaluate the amount of water absorption supplied by the pouring method and spraying method, to investigate the effects of water absorption on the thermal conductivity of an insulation material, and modeling the relation between water absorption and thermal conductivity. E-glass, a kind of glass fiber, and HYPERLITE, mainly composed of pearlite, are selected, to compare hygroscopic and insulation properties. E-glass is found to have much higher water absorptivity, compared to HYPERLITE. The thermal conductivity of the water-absorbed E-glass is increased by more than 150%, compared to that of no absorption, while variation of the thermal conductivity of HYPERLITE with water absorption is insignificant. A three-stage model of water absorption for thermal conductivity is developed, and the modeling results are found to be in good agreement with the experimental data.

• Applied Biological Chemistry
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• v.37 no.2
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• pp.94-99
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• 1994

Bran structure and water uptake rate for brown rices of thirteen japonica and twelve Tongil cultivars were investigated. The japonica type was shorter in length and had lower value in the ratio of length to width than Tongil one. No differences were observed in width and weight between the two types. The number of aleurone layer and the thickness of bran layer were higher in dorsal side than in ventral side in all rice cultivars. The structure in ventral side was similar but the number of aleurone layer in dosal side was higher in japonica samples. There were no significant differences in water uptake rates showed no correlation with the bran structure.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.3
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• pp.165-169
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• 2001

Seed coat of sword bean (Canavalia gladiata) is very thick and hard, it is difficult to absorb water during germination and it requires much time that cotyledon come out from seed coat since seminal root appearanced. Therefore this experiment was carried out to increase the germination rate by easing water absorption through mechanical scarification on seed coat. Non-scarification seed did not germinated at 7 days after treatment but scarification seed showed germination rate of 98%. Therefore mechanical scarification of seed coat was increased germination rate. Non-scarification seed absorbed less than 10% water of dry weight at 8 hours after treatment but scarification seed absorbed about 90% water at 7 hours after treatment and more than 150% water at 8 hours and swelled about 1.4-1.5 times in length and width of seed. Germination rate of scarification seed was high under high temperature and it was 96% and 93% at $25^{\circ}C$ and 3$0^{\circ}C$, respectively. The rate of cotyledon emergence on clay loam soil was the highest among bed soils. Soaked seed after mechanical scarification in distilled water was germinated faster than non-soaked seed on early in bed soil. The rate of cotyledon emergence was more than 92% at 9 days after sowing but non-scarification and soaked seed was germinated late and showed very low germination rate as 67%.