• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.4
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• pp.259-264
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• 2011

Gas hydrate is formed by physical binding between water molecule and gas such as methane, ethane, propane, or carbon dioxide, etc., which is captured in the cavities of water molecule under the specific temperature and pressure. $1\;m^3$ hydrate of pure methane can be decomposed to the methane gas of $172\;m^3$ and water of $0.8\;m^3$ at standard condition. If this characteristic of hydrate is reversely utilized, natural gas is fixed into water in the form of hydrate solid. Therefore, the hydrate is considered to be a great way to transport and store of natural gas in large quantity. Especially the transportation cost is known to be 18~25% less than the liquefied transportation. However, when methane gas hydrate is artificially formed, its reaction time may be too long and the gas consumption in water becomes relatively low, because the reaction rate between water and gas is low. Therefore, for the practical purpose in the application, the present investigation focuses on the rapid production of hydrates and the increment of the amount of captured gas by adding zeolite into pure water. The results show that when the zeolite of 0.01 wt% was added to distilled water, the amount of captured gas during the formation of methane hydrate was about 4.5 times higher than that in distilled water, and the methane hydrate formation time decreased at the same subcooling temperature.

• Journal of Practical Agriculture & Fisheries Research
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• v.13 no.1
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• pp.115-129
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• 2011

This study was performed to investigate the effects of food organism and water quality on the mass production of larval red marbled rockfish, Sebastiscus tertius. When rotifer cultured with different food stuffs were supplied to the larvae, rotifer cultured with concentrated Chlorella provided the highest in total length 11.9 mm and survival rate was the highest by 47.0% fed that cultured with ω-yeast Growth and survival rate of larvae fed on enriched rotifer with ω-yeast and super selco, super selco of enriched treatment showed that the best results not only growth but also survival rate. For instance of Artemia, the growth was not significantly different with other treatment but the survival rate was significantly higher than others. The growth of larvae fed with different diets indicated that rotifer+Artemia+commercial diet treatment was the highest on the total length and body weight 18.40 mm and 18.1 mg, respectively, whether the survival rate was rotifer+Artemia treatment was the highest as 57.5%. The most effective density of Chlorella was 10×10⁵ cells/ml for growth of larvae. That density showed that total length and body weight were 11.83 mm and 14.3 mg, respectively. The survival rate was the most effective for 20×10⁵ cells/ml of Chlorella density. That density represented the highest survival rate as 54.5%. Comparing of PSB adding effect, PSB density 15×10⁵ cells/ml was the most effective for growth of larvae and but for survival rate PSB density 10×10⁵ cells/ml was the highest as 61.0%.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.2
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• pp.224-230
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• 2009

This study was to investigated the effects of adding of medicinal herbal (cinnamon, licorice and Bokbunja) to ground beef during storage by examining surface color, water holding capacity, cooking loss, increased rate of thickness, decreased rate of diameter, pH, VBN (volatile basic nitrogen) content and TBARS (2-thiobarbituric acid reactive substances) values of the beef under cold ($4{\pm}1$) storage conditions for 9 days. Four types of ground beef were prepared by adding the follow: 10% water (control), 10% cinnamon extracts (T-1), 10% licorice extracts (T-2), and 10% Bokbunja extracts (T-3). The $L^*$ (Lightness) and $a^*$ (Redness) values of the beef significantly decreased (p<0.05) whereas no significant changes were shown in the $b^*$ (Yellowness) value during storage, and which were not influenced by the additions of herbal extracts. Water holding capacity was significantly increased during cold storage (p<0.05), and was not influenced by the addition of the extracts. The cooking loss of the control, T-2 and T-3 were significantly decreased during cold storage (p<0.05), and T-1 had no significant changes in cooking loss. There were no significant changes in the thickness and diameter during cold storage, and which were not influenced by the addition of the extracts. The pH of the control decreased until 6 days of storage, but increased at 9 days, and the pH levels of T-1, T-2 and T-3 decreased during cold storage. VBN content was increased during cold storage and the VBN contents of the samples containing herbal extracts were lower than that of the control. In addition, the TBARS values of the ground beef containing the extracts were lower than that of the control.

• New & Renewable Energy
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• v.8 no.2
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• pp.24-32
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• 2012

Natural gas hydrates have a high potential as the 21st century new energy resource, because it have a large amount of deposits in many deep-water and permafrost regions of the world widely. Natural gas hydrate is formed by physical binding between water molecule and gas mainly composed of methane, which is captured in the cavities of water molecules under the specific temperature and pressure. $1m^3$ methane hydrate can be decomposed to the methane gas of $172m^3$ and water of $0.8m^3$ at standard condition. Therefore, there are a lot of practical applications such as separation processes, natural gas storage transportation and carbon dioxide sequestration. For the industrial utilization of methane hydrate, it is very important to rapidly manufacture hydrate. However, when methane hydrate is artificially formed, its reaction time may be too long and the gas consumption in water becomes relatively low, because the reaction rate between water and gas is low. So in this study, hydrate formation was experimented by adding natural zeolite and Synthetic zeolite 5A in distilled water, respectively. The results show that when the Synthetic zeolite 5A of 0.01 wt% was, the amount of gas consumed during the formation of methane hydrate was higher than that in the natural zeolite. Also, the natural zeolite and Synthetic zeolite 5A decreased the hydrate formation time to a greater extent than the distilled water at the same subcooling temperature.

• Food Science of Animal Resources
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• v.37 no.2
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• pp.210-218
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• 2017

The intake of dietary salt through food now exceeds current nutritional recommendations and is thought to have negative effects on human health, such as the increasing prevalence of hypertension. This study was performed to investigate whether $W_1/O/W_2$ double emulsions can be used to enhance the saltiness of cheese without increasing the salt content ($W_1$ is distilled water or 1% abalone hydrolysate, and $W_2$ is 1% NaCl or 1% abalone hydrolysate + 1% NaCl solution). We also investigated the effect of adding abalone hydrolysate to the double emulsion as a saltiness enhancer. The cheeses were physico-chemically evaluated to determine curd yield, pH value, moisture content, color, texture, salt release rate, and sensory properties. No significant differences were observed in curd yield, pH value, moisture content, lightness, or redness between the cheeses made with and without the double emulsion. However, in the evaluation of salt release rate, fresh cheese made with double emulsion ($W_1$ = distilled water, $W_2$ = 1% NaCl + 1% abalone hydrolysate) was detected earlier than the control or the other treatments. In the sensory evaluation, fresh cheese made with the double emulsion showed higher scores for saltiness and overall preference than the control or the other treatments. We concluded that abalone hydrolysate encapsulated in a double emulsion ($W_1$ is water and $W_2$ is abalone hydrolysate and NaCl solution) could enhance the saltiness of fresh cheese while maintaining the same salt concentration, without altering its physical properties.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.1
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• pp.99-106
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• 2006

New application of rice was carried out by coating the rice with the mixture solution of ginseng and chungkukjang water extract The physicochemical characteristics of the coated rice were investigated. Moisture content of uncoated (15.26%) and coated rice$(15.57\sim15.66%)$ was not different significantly. The contents of crude protein, crude fat, and crude ash of the coated rice were higher as much as $4.28\sim11.82%\;8.47\sim47.46%$, and $11.54\sim42.31%$ than those of control, respectively. As total free amino acids in coated rice were increased by augmenting the amount of the extract, total free amino acids according to rate was increased to $3.1\sim7.8$ times. The major amino acids in the coated rice was alanine$(19.56\sim39.88\;mg%)$, leucine$(5.14\sim17.66\;mg%)$, and proline$(9.98\sim16.82\;mg%)$. Of those amino acids, alanine and $\gamma-aminobutyric$ acid in only coated rice were detected to the level of $19.56\sim39.88\;mg%$ and $7.78\sim12.36\;mg%$ respectively. The calcium amount of coated rice was increased to 15% to 20%. As increasing the coating rate, hardness, cohesiveness, chewiness, and brittleness of coated rice were decreased, but springiness was increased. Before cooking, the color of coated rice appeared yellow and after cooking turned to the light yellow. The color intensity was increased feasibly as increasing the coating rate. The sensory characteristic of rice coated manufactured by adding 15% of the extract was best and found to be similar to that of the control.

• Journal of Adhesion and Interface
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• v.22 no.1
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• pp.22-28
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• 2021

Products using diatomaceous earth, which are used in various fields, are optimized for moisture absorption, but have problems such as high hardness, powder flying, and rough surface feel. To improve this, an olefin-based foam having low hardness and high elasticity was prepared by adding an excessive amount of inorganic material using EVA (Ethylene vinyl acetate) having low hardness and excellent elasticity. Diatomaceous earth was added to impart moisture absorption characteristics of the foam, and the moisture absorption/drying characteristics showed a moisture absorption rate of about 10 to 15% and a moisture drying rate of 10 to 70% depending on the content of the diatomaceous earth. Through this study, it was possible to manufacture a water-absorbing olefin-based foam with diatomaceous earth added, and it was confirmed that the diatomaceous earth added to the foam had a great influence on water absorption and dissipation due to its microstructure and characteristics.

• The Korean Journal of Physiology
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• v.7 no.1
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• pp.23-31
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• 1973

Numerous factors concern with the absorption of substances through the membrane of the gastrointestinal tract. To simplify the experimental condition, present work has been restricted to observe the disappearance rate of substance from the intestinal loop which was made in the jejunum, 70 cm apart from the pylorus of the adult rabbit. The purpose of the study is to clarify the absorption of urea through the jejunal wall is solely attributable to the concentration difference between the luminal fluid and plasma, and to observe the effect of adding red pepper upon the rate of absorption. The rabbits were anesthetized with nembutal, 35mg/kg I.V. Jejunal loop was made by ligating at 2 spots, 70 cm and 80cm apart from the pylorus. After rinsing with normal saline solution through the polyethylene tubing inserted from the end of the loop, 8 ml of test solution was placed through the same tubing. The test solution contained 200 mg% of urea and 150mg% of polyethylene glycol(M.W. 4,000) in normal saline solution. Right after placing the test solution the first specimen was taken through the tubing, and successive samplings were performed at 5, 10, 20, and 30 minutes. Logarithm of the difference of urea concentration between the luminal fluid and plasma was plotted against time elapsed after the onset of the experiment. If straight line is revealed, it would verify the nature of transport mechanism as diffusion, obeying the Fick's principle. The concentration of polyethylene glycol (PEG) was also measured in order to examine the change in the volume. PEG was used as the marker substance because it is not absorbable in the intestinal tract. Consequently the concentration of PEG relates inversely to the volume of the loop. Instantaneous concentration of urea in the loop times the volume will give the amount of urea remaining in the luminal fluid. The change in the amount of any substance is directly relate to the volume of the compartment and differs from the change in the concentration which is independent of the volume. After completion of the experiment without red pepper, it was added in the test solution and was centrifuged after thorough mixing. Supernatant of the mixture was placed in the loop and similar sampling were performed with the same time intervals that of previous run in order to observe the effects of the red pepper on the passive transport of the water soluble small substance, urea. The results obtained were as follows: 1. Logarithm of the concentration difference of urea between the luminal fluid and plasma was diminished exponentially as time elapsed. The decay constant in the experiment without red pepper was 0.0563/min. By adding red pepper in the test solution as much as the concentration rose to 4,000 mg% and 8,000 mg%, the decay constants were lowered to 0.0493/min and to 0.0506/min, respectively. The time interval by which the concentration difference dropped to one half of the initial value was prolonged. Without red pepper the half concentration time was 13.30 minutes, and by adding extract of red pepper, 15.31 minutes and 15.71 minutes were revealed. 2. The profile of the diminishing rate of tile amount of urea was quite different from that of the concentration because of the change in the volume of the loop during the observed period. 3. By adding the extract of red pepper, it slowed down the rate of absorption of urea in the intestinal loop, suggesting an increase in the diffusional barrier. 4. Larger dosage of red pepper brought an increase in the secretion of intestinal fluid with concomitant expansion of the luminal volume, and the retardation of the absorption of urea was noticed. This effect was largely dependent on the sensitivity of the individual animal to the red pepper, extract. The amount of urea remained after 10 minutes interval was 55.5% of the initial amount in the experiment without red pepper. On the other hand it was not consistent after administration of red pepper, showing 50.6% and 66.5% of the initial figures by adding 400 mg and 800 mg of red pepper in the test solution, respectively. It was postulated that symptom of diarrhea often encountered by taking a hot (red pepper) food might be attributable to the increase of secretion and the retardation of absorption in the intestinal tract.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.258-258
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• 2006

Electrospun fibers of poly(vinyl alcohol) (PVA) were successfully prepared and applied as drug carriers for transdermal drug delivery system. Sodium Salicylate (SS) was the model drug and it was incorporated in the PVA fibers by adding 20 % of SS in a PVA solution prior to electrospinning. Electrospinning of SS-containing PVA solution resulted in the formation of beaded fibers. In order to control the rate of SS release and decrease water solubility of PVA, the SS-loaded electrospun PVA mat was cross-linked by either glutaraldehyde or glyoxal vapor. The morphology, thermal behavior, swelling behavior, release characteristic, kinetics of drug release and also toxicity of the cross-linked sample were investigated.

• Journal of Ginseng Research
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• v.15 no.3
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• pp.167-170
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• 1991

Radiation protective fraction was Isolated and partially purified from Korean white ginseng. The effect of the fraction was studied on the cell survival of W-damaged CHO-Kl cells. As a result, it was found that the fraction increased the survival rate of damaged cells significantly within the dose range of which cytotoxicity did not appear This fraction was separated into two parts by adding butanol, namely the precipitated protein component and the butanol extract. Damaged cells were treated with each of these components and their survival rates were measured. The protein component demonstrated significant increase in the survival rates, while the butanol extract showed no such increment. These results suggest that the radiation protective effect of the ginseng fraction is originated from the butanol-precipitated protein component, not from the butanol-soluble compounds.