• Journal of the Microelectronics and Packaging Society
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• v.6 no.1
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• pp.23-29
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• 1999

An yttria-stabilized zirconia(YSZ) thin film on a porous NiO-YSZ substrate for an anode support type solid oxide fuel cell(SOFC) was prepared by an electrophoretic deposition(EPD). Deposition condition and film properties in order to obtain the homogeneous YSZ thin film from the EPD solution with different polarity were studied. In different case of alcohol solution, hydrogen gas was produced in aqueous solution from the electrolyte reaction under constant current above 0.138 mA /$\textrm{cm}^2$.Its reaction generated the bubble-formed defect in the deposited film and decreased weight of the film. The homogeneous YSZ thin film was formed in alcohol solution at a constant current, 0.035 mA /$\textrm{cm}^2$ for 10 s.

• Korean Journal of Food Science and Technology
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• v.10 no.2
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• pp.151-156
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• 1978

Ginseng jellies and candies were prepared by adding Ginseng extracts as final concentration of 0.5% and 1% for jellies and 0.7% for candies. Feeding experiments of the diets containing Ginseng extract were carried out for evaluation in respects of growth rate, feed efficiency ratio, organ weight change, hematocrit value, and blood cholesterol content by feeding rats for 6-week. The results of Ginseng supplemented diets were not significantly different from those for the control. Liver, spleen and kidney cells of Ginseng products feeding rats appeared no abnormalities to compare to the control rats.

• Journal of Korea Foundry Society
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• v.18 no.4
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• pp.389-397
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• 1998

회주철 모재의 표면에 감압 플라즈마 용사법으로 실리콘 분말을 피복시킨 후 $CO_2$ 레이저를 이용하는 표면 합금화로 고온 내스케일성이 향상된 표면 개질층을 제조하였다. 실리콘의 표면 합금층에는 응집상의 흑연(chunky graphite)이 $Fe_5Si_3$로 구성된 망상의 화합물 기지속에 정출하는 조직특성을 보였다. 대기 분위기에서 18.0ks동안 열중량측정(TG)한 결과 실리콘 표면 합금층의 무게 증가율은 회주철 모재에 비하여 923K에서는 약 1/3, 1098K에서는 약 1/10을 나타내었다. 그리고 1098K에서 18.0ks동안 유지시킨 주철모재 시편에서 원래의 모재표면을 기준으로 다공성의 외부스케일과 편상흑연을 따라 생성된 내부스케일로 구성된 두께 $60{\sim}70\;{\mu}m$의 두꺼운 산화스케일이 생성되었으나, 실리콘의 표면 합금층에서는 두께 $3{\sim}5\;{\mu}m$의 치밀한 외부 산화스케일만이 생성되었다. 실리콘 합금층의 단면 미소경도값은 MHV $300{\sim}1100$으로 그 변동폭이 심하였으나, 진공분위기에서 열처리(1223K, 18.0ks)한 경우 미소경도값의 편차는 MHV $300{\sim}500$으로 개선되었다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.5
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• pp.816-822
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• 2001

The thermoforming process is widely used in the plastics industry to produce articles for the packaging, automotive, domestic construction and leisure industries. The microcellular foaming process appeared at M.I.T. in 1980s to save a quantity of polymer materials and increase their mechanical properties. The glass transition temperature of polymer materials is one of many important process variables in appling the microcellular foaming process to the conventional thermoforming process. The goal of this research is to evaluate the relation between gas absorption and glass transition temperature in batch process using microcellular foaming process. The weight gain ratio of polymer materials has a conception of gas absorption. Polymers such as acrylonitrile-butadiene-styrene(ABS), polystyrene(PS) have been used in this experiment. According to conventional Chows model and Cha-Yoon model, it was estimated with real experimental result to predict a change of glass transition temperature as a function of the weight gain ratio of polymer materials in batch process to gain microcellular foamed plastic products.

• Journal of Environmental Health Sciences
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• v.19 no.1
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• pp.66-70
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• 1993

Introduction : Methanethiol is a toxicant that is a byproduct in the industrial process (oil refinery), and it is produced in vivo from methionine via transamination in case of its overintake. And it also can be generated by the action of mucosal thiol Smethyltransferase on hydrogen sulfite which is formed by anaerobic bacteria in the intestinal tract. The toxicity of methanethiol has often been suggested as one of endogenous factors involved in the pathogenesis of hepatic encephalopathy. Furthermore, methanethiol could cause the membrane damage and inhibition of some membrane protective enzymes.

• Composites Research
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• v.20 no.4
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• pp.31-41
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• 2007

Dome shape design methods of Filament Winding (FW) composite pressure vessel, which can suggest various dome contour according to the external loading conditions, were investigated analytically and numerically. The performance indices(PV/W) of the pressure vessels with same cylinder radius and boss opening but different dome shape were evaluated by finite element analysis under the internal pressure loading condition. The analysis results showed that as the dome shape becomes flat, the performance index decreases significantly due to the reduced burst pressure. Especially, for the case of the high value of the parameter ro, the ratio between the radii of the cylinder part and the boss opening, the flat dome is disadvantageous in the aspect of the weight reduction, and additional reinforcing dome design technique should be required to increase the burst pressure. For example, above ro=0.54 condition, the dome shape change according to the loading condition could cause the low burst pressure and increase of composite weight in dome region and is not recommendable except for the special case that maximum inner volume or sufficient space between skirt and dome is the primary design objective. However, at ro=0.35, the dome shape change brings not so significant differences in the performance of FW vessel.

• Biomedical Science Letters
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• v.1 no.1
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• pp.37-43
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• 1995

To evaluate an effect of xanthine oxidase(XO) reaction system on the carbon tetrachloride($CCl_4$) metabolism, $CCl_4$ was given twice at 0.1ml/100g body wt. at intervals of 18 hour to the rats and those pretreated with allopurinol (50mg/kg. body wt.). The influence of XO on the metabolism of $CCl_4$ was focused on the degree of liver damage and the activities of a $CCl_4$ metabolizing marker enzyme, glucose-6-phosphatase. The increasing rate of liver weight per body weight and the levels of serum alanine aminotransferase to the control group were more decreased in allopurinol-pretreated rats than in those treated with $CCl_4$ alone. The liver XO activities were more increased in $CCl_4$-treated rats than the control group and the $CCl_4$-treated rats pretreated with allopurinol showed a decreased activities of XO compared to the $CCl_4$-treated rats. The type conversion (type D --> type O) rate was more decreased tendency in allopurinol pretreated rats than those treated $CCl_4$ alone. In dialyzed liver enzyme preparations, all of the xanthine oxidase activities: $CCl_4$-treated, allopurinol and $CCl_4$-treated rats pretreated with allopurinol showed the more increased Vmax value than the control group, but similar Km value. Moreover, $CCl_4$-treated rats pretreated with allopurinol showed the more increased Vmax value than the group treated with $CCl_4$ alone. In conclusion, it can not be negate the possibility of metabolism of $CCl_4$ by the xanthine oxidase enzyme system.

• Biomedical Science Letters
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• v.6 no.3
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• pp.193-199
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• 2000

To evaluate an effect of aging on the xylene toxicity, 50% m-xylene in olive oil (0.25 ml/100 g body wt.) was administered to 5 week and 12 week-old rats one times intraperitoneally and sacrificed at 24 hrs afterwards. The increasing rate of urinary m-methylhippuric acid concentration was higher in 12 week-old rats than 5 week-old rats by the treatment of m-xylene. On the liver function findings, i.e., liver weigh/body weight (%), serum levels of ALT activity and hepatic malondialdehyde content, 12 week-old rats showed more severe liver injury than 5 weeks those in xylene-treated rats. And the hepatic cytochrome P-450 contents was higher in 12 weeks rats than those of in 5 week-old rats, but the increasing rate of that was lower in 12 week-old rats. Hepatic alcohol dehydrogenase activity was also higher in 12 week-old rats than in 5 week-old rats whereas the increasing rate of that was higher in 5 week-old than those in 12 week-old rats by the xylene treatment. Furthermore, the hepatic aldehyde dehydrogenase activities were no differences between the 5 and 12 week-old rats both in the control and xylene-treated group. In conclusion, age may influences upon the hepatotoxicity with xylene and it may be responsible for xylene metabolism in rats.

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.283-288
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• 2007

The effects of Ge-Geol radish powder on the physical and sensory properties of wet noodles were investigated by adding 4-16% Ge-Geol radish powder based on the flour source. The Ge-Geol radish powder additions significantly increased the redness of the uncooked and cooked noodles. For the texture profile analysis (TPA) of the wet noodles with added Ge-Geol radish powder, hardness, adhesiveness and resilience decreased, whereas chewiness increased. Changes in the volume and weight of the cooked noodles were not significantly different according to Ge-Geol radish powder concentration, but the turbidities of the soup increased. In sensory test, overall acceptability was significantly higher for the noodles with added Ge-Geol radish powder of concentrations between 4-8%. These samples had similar sensory texture properties as the control and had peculiar hot and cool tastes of the radish. Therefore, adding Ge-Geol radish powder at concentrations below 8% was good for making noodles that maintained a natural texture, and also gave an characteristic radish-like flavor to the noodles.

• Korean Journal of Food Science and Technology
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• v.40 no.5
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• pp.528-533
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• 2008

The principal objective of this study was to assess the quality characteristics of noodles prepared at ratios of 0% (I), 1.4% (II), 2.8% (III), and 4.2% (IV) Dioscorea japonica powder, based on the wheat flour weight. The lightness of the uncooked and cooked noodles decreased significantly as the amount of Dioscorea japonica powder increased. The yellowness of the cooked noodles were reduced significantly, but the redness of all samples were significantly increased with increasing amounts of Dioscorea japonica powder. The rate of weight increase and volume increase of the noodles, as well as the density, pH, and turbidity of the soups were also assessed. The cohesiveness and gumminess of samples III and IV were significantly lower than those values in samples I and II. The results of our sensory evaluation test evidenced no significant differences in appearance and flavor among all samples. The colors of I and II were better than those of III and IV. The taste and texture scores of IV were the highest, and as a result the overall acceptability of III was most preferred.