• Journal of the Korean Ceramic Society
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• v.38 no.10
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• pp.894-900
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• 2001

The spinel $Li{Mn_2}{O_4}$ catalysts for $CO_2$ decomposition were synthesized by a sol-gel method using manganese acetate and lithium hydroxide as starting materials through drying at $150^{\circ}C$ for 12 hrs under oxygen atmosphere followed by heat treatment at $480^{\circ}C$ for 12 hrs. The synthesized $Li{Mn_2}{O_4}$ were reduced by hydrogen for 3 hrs at various temperatures and the decomposition rate of carbon dioxide was investigated at 300, 325, 350, 375 and $400^{\circ}C$ using the $Li{Mn_2}{O_4}$ reduced by hydrogen gases. As a result of experiment, the optimum temperature of hydrogen reduction and $CO_2$ decomposition was shown $350^{\circ}C$. The physicochemical properties of the spinel $Li{Mn_2}{O_4}$ the reduced $Li{Mn_2}{O_4}$ and the $Li{Mn_2}{O_4}$ after $CO_2$ decomposition were examined with XRD, SEM and TGA.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1095-1103
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• 1996

In order to minimize the deterioration of dried apple quality, changes of free sugar content, organic acid and ascorbic and during osmotic dehydration with sucrose at various temperature, concentration and immersion time were investigated in this study, total sugar increased as the temperature, concentration and immersion time were increased. Sucrose showed the largest change in content while fructose and glucose showed no and small changes, respectively. Large amounts of malic and fumaric acids, and small amounts of oxalic, citric, maleic and succinic acids were detected. Organic acids were high at low temperature treatment, and became higher with increasing concentration. Loss of ascorbic acid was small at the low temperature and high concentration. Effect of immersion time was negligible. Changes of free sugar, and organic and ascorbic acid followed the first-order and second-order reaction rate equations, respectively. Arrhenius equation was applied to determine the effect of temperature on reaction rate constants with high $r^2$. To predict the changes of quality, a model was established by using the optimum functions of temperature, concentration and immersion time. The model had high $r^2$ value for the quality changes during drying.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.2
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• pp.114-118
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• 2009

With the advance of industrialization and urbanization, a lot of waste has been discharged and treated by incineration. But fly and bottom ashes are generated in this process. In addition, the treatment method to recycle sewage sludge and melting slag is required to manage these wastes. The objective of this research was to prepare of multi-functional brick which were made from MSWI (Municipal solid wastes incinerator) fly ash, sewage sludge and slag. The bricks were made by mixing raw materials and then drying for 24 hours. Next, they were dried for 24 hours at $160^{\circ}C$ and fired for 2 hours. Calcination temperature was changed to discuss the effect of temperature from $1,080^{\circ}C$ to $1,130^{\circ}C$. Compressive strength of a brick was creased with the increase of temperature. To increase mixing ratio of fly ash and slag reduce the compressive strength the optimal condition was the mixing ratio of fly ash : melting slag : sewage sludge : clay as 10 : 20 : 5 : 65 and $1,150^{\circ}C$ of calcination temperature. Compressive strength was obtained as about 41 MPa at this condition.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.931-934
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• 2002

To establish the optimal conditions for increasing oil yields from grape seed, extraction solvent, extraction time, and temperature were examined. Using grinding, grinding and roasting, grinding and steaming, and grinding, roasting, and steaming methods. Pressing extraction method resulted in 34.0% oil yield. Grinding and roasting, grinding and steaming, and grinding, roasting, and steaming gave 64.3, 63.0, and 65.6% yield, respectively. Ether solvent treatment resulted in 77.4 and 80.9% recoveries after 24 and 48 h static, respectively. The results of sensory evaluation revealed, oils extracted under optimal condition showed the best flavor, aroma, and whor, followed by grinding, grinding and roasting, grinding, roasting, and steaming, and grinding and steaming. Taking these results together, the optimal methods for oils extraction from grape seed were as follows: grape seed ${\rightarrow}$ washing ${\rightarrow}$ drying ${\rightarrow}$ roasting ($95{\sim}100^{\circ}C$ for 20 min) ${\rightarrow}$ cooling (room temperature) grinding ${\rightarrow}$ (0.5 mm>) ${\rightarrow}$ steaming ($0.8{\sim}0.9\;kg{\cdot}f/cm^2$ for 10 min) ${\rightarrow}$ pressing ($1st\;400\;kg/cm^2\;for\;2{\sim}3\;min,\;2^{nd}\;550{\sim}600\;/cm^2$ for 10 min, $3^{rd}\;700kg/cm^2$ for 60 min) ${\rightarrow}$ oils (yield $;85{\sim}90%$).

• Journal of Plant Biotechnology
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• v.33 no.2
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• pp.133-137
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• 2006

Evaluation of physiological performance of trehalose-producing transgenic rice line was conducted to investigate drought tolerance at early growth stage. Under artificially induced drought condition of 8% polyethylene glycol 6000, this transgenic rice line had leaf photosynthetic rate of 11.08 uml CO$_2$ $m^{-2}s^{-1}$, leaf transpiration rate of 8.38 mmol $H_2O$ $m^{-2}s^{-1}$ and leaf water potential of -1.12 MPa after 96 hours of treatment. Nakdongbyeo, the parent of this tyansgenic rice line, had photosynthetic rate of 15.42 $\mu$mol CO$_2$ $m^{-2}s^{-1}$, leaf transpiration rate of 8,04 mmol $H_2O$ $m^{-2}s^{-1}$ and leaf water potential of -0.88 MPa. The other variety used in this experiment for comparison, IR 72, showed higher values than both tyansgenic rice line and variety Nakdonbyeo on all three parameters; leaf photosynthetic rate of 20.61 $\mu$mol CO$_2$ $m^{-2}s^{-1}$, leaf transpiration rate of 12.88 mmol $H_2O$ $m^{-2}s^{-1}$, and leaf water potential of -0.82 MPa. So this transgenic rice line did not show superior performance in leaf transpiration rate, leaf photosynthetic rate and leaf water potential compared to variety Nakdongbyeo. This result along with visual observation on leaf rolling and drying during the experimental period indicated poor physiological performance of this transgenic rice line. Further studies on metabolic status of stress-induced trehalose, along with study on physiological response of this transgenic rice line during drought stress would shed more light on overall physiological performance of this transgenic rice line.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.2
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• pp.133-139
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• 2018

Chemically damaged hair is vulnerable to external stimuli in daily life due to the weakened physical properties of the hair strand itself. The purpose of this work was to determine whether chemical conjugation between hair keratin proteins restores tensile strength and thus results inpreventing further deterioration under repeated combing. A model damaged hair tress was produced by a typical perm-process. Then, it was internally crosslinked by the bifunctional crosslinker (3-aminopropyl)triethoxysilane (APTES), via both silane coupling and carbodiimide chemistry. Physical properties, including tensile strength, Young's modulus, and plateau stress, were measured to verify the effect of internal crosslinking, and the existence of crosslinking was verified by Fourier transform infrared (FT-IR) spectroscopy. The degrees of hair breakage and split ends were evaluated by repeated combing-drying tests. Physical properties of chemically damaged hair were restored by internal crosslinking. Successful crosslinking of APTES via both silane coupling and carbodiimide chemistry was verified by FT-IR spectra. Prevention of breakage and split ends after repeated combing with heat was observed. Human hair can be weakened by chemical damage including perm-processing, so restoring such properties is a major issue in the hair care industry. This work shows that internal crosslinking of damaged hair via chemical conjugation would be a potent method to restore the healthy hair.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1549-1556
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• 1999

This study was conducted to investigate the effects of pre-treated sub-ingredients and deodorization materials on the smell intensity of Kimchi during fermentation.Among the various sub-ingredients of Kimchi, garlic, ginger and green onion have comparatively strong smell. The smell intensities of the sub-ingredients, which were pre-treated with various patented methods were examined using the sensory evaluation method and AromaScan. The results showed that the good methods to reduce the smell of sub-ingredients were hot air drying and soaking with heating treatment. The pH, titratable acidity and the number of microorganism of Kimchi prepared with pre-treated sub-ingredients were not different among samples during fermentation. The smell intensity of the Kimchi with pre-treated sub-ingredients was weaker than that of control until ten fermentation days, but the smell intensity after 10 days of fermentation was not different among samples. The addition of ${\alpha}-cyclodextrin\;and\;{\beta}-cyclodextrin$, which are known to have deodorization effect, at a level of 0.1% respectively, to Kimchi resulted in no difference in the pH, titratable acidity and smell intensity during fermentation at $10^{\circ}C$ compared to those of control Kimchi. However, the addition of deodorizer reduced sulfide classes such as methyl allyl sulfide, dimethyl disulfide, allyl sulfide, methyl propyl disulfide up to 50%.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.6
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• pp.812-815
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• 2009

The effects of processing conditions on the ${\alpha}$-amylase activity of radish were investigated at various temperatures, pHs and drying conditions. The ${\alpha}$-amylase activity of radish root was 3.1-fold higher than that of radish trunk. As the freeze-dried radish was incubated at various temperatures and pHs, ${\alpha}$-amylase activity was stably maintained at pH range of $4{\sim}7$ and temperature of $25{\sim}40^{\circ}C$. When radish was processed to kakdugi and danmooji, the residual ${\alpha}$-amylase activity was 45.39% and 19.19%, respectively. Consequently, the ${\alpha}$-amylase activity was greatly affected by processing conditions such as heat treatment and pH. It is suggested that radish should be processed at below $60^{\circ}C$ and at neutral to acidic pH condition.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.6
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• pp.1247-1260
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• 2009

This dissertation aims to study the five tastes in the Yellow Emperor's Canon of Internal Medicine. Medicinals as well as Foods are classified by the five tastes: sweet, sour, bitter, salty and pungent, which can be tasted by the tongue. With the development of the theory dealing with the medicinal properties, some flavors are summarized out of clinical actions of medicinals, therefore, there is a little difference between the flavors of medicinal herbs and the tastes got by tongue. Each taste acts on or has direct influence on a specific vital organ, and each of which has different physiologic actions. Taste also has a long-term or post digestive effect on the body and its metabolism. When each taste is consumed in moderation, it benefits the corresponding organ. Over-indulgence in any taste harms the organ and creates imbalance among the five vital organ systems. The Korean medicinal herbs with same flavor mostly possess similar actions while the medicinal herbs with different flavors show different actions in the treatment, which are shown as follows. Sour has absorbing, consolidating and astringent actions and acts on the liver. Bitter has the actions of drying or resolving dampness, purging and lowering and acts on the heart. Sweet has the nourishing, harmonizing and moistening actions and acts on the spleen. Pungent has an action of dispersing and promoting circulation of gi and blood and acts on the lungs. Salty has the effects of softening hard nodes or masses and promoting defecation, etc and acts on the kidneys. The five organ systems control and support each other. Proper coordination only exists when there is no one organ stronger or weaker than the rest. Since the five tastes have direct influences on the five organs, the diet we take should have a good combination of the five tastes in order to promote internal balance and harmony. They control our well-being and create dietary balance. Excessive consumption of any of these could result in adverse effects. In a word, when the properties of the five tastes respectively are distinguished, their natures and flavors cannot be separately considered. I think the harmonization of food and medicinals should be stressed on good nutritional diet to maintain good health. The traditional belief that food and medicine share the same origin is a part of Korean medicine tradition.

• Korean Journal of Food Science and Technology
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• v.50 no.3
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• pp.292-296
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• 2018

Softening effects of enzyme following pre-treatments were examined. Four pre-treatments: raw (R), heat (H), heat and freeze-thawing (HFT), heat and freeze-drying (HFD) were applied to carrot. Subsequently, each treated sample was immersed in 10% celluclast enzyme solution for up to 6 h and then their properties were compared. The minimum and the maximum color change was observed in HFD and H, respectively. R showed no change in hardness after 6 h immersion, indicating that the enzyme did not penetrate the carrot. The number and size of pores were greater in samples undergone HFT or HFD as observed by microstructure analysis using SEM, and HFD caused 99.5% reduction in hardness after 6 h immersion. After 6 h immersion post-HFT or 3 h immersion post-HFD, the hardness was less than $20,000N/m^2$, indicating tongue ingestion was possible, and the samples retained their original shape and easily collapsed by spoon pressing.