• JOURNAL OF ELECTRICAL WORLD
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• no.10 s.9
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• pp.34-39
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• 1967

• 보건세계
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• v.37 no.12 s.412
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• pp.69-70
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• 1990

• 보건세계
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• v.50 no.1 s.557
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• pp.36-39
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• 2003

• 보건세계
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• v.51 no.8 s.576
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• pp.32-35
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• 2004

• 보건세계
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• v.51 no.11 s.579
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• pp.46-50
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• 2004

• 가정의 벗
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• v.35 no.6 s.406
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• pp.6-7
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• 2002

• 우리들 숲
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• s.9
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• pp.6-7
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• 2006

• Korean Chemical Engineering Research
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• v.50 no.6
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• pp.1021-1026
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• 2012

The transient mass transfer in a single droplet system consisting of 1-octanol (continuous phase)/aqueous succinic acid solution (dispersed phase) was investigated in the presence of chemical reaction, which is acid/anion exchange reaction of succinic acid and tri-n-octylamine (TOA). This succinic acid extraction by TOA can be considered to occur at the interface between organic and aqueous phase, that is, heterogeneous reaction system. The basic properties of the system such as viscosity, density, distribution coefficient, terminal velocity of droplet, and diffusion coefficient were measured experimentally or calculated theoretically, and used for theoretical calculation of characteristic parameters of mass transfer later. The effects of succinic acid concentration on the terminal velocity was negligible in the existence of TOA, although the terminal velocity increases with succinic acid concentration in the absence of TOA. On the contrary, the terminal velocity decreases with TOA concentration. While droplets falls through organic phase, the trajectory of droplets is observed to oscillate around its vertical path. A mass trnasfer cell was prepared to monitor the mass transfer behavior in a single droplet and used to measure the mean concentration of succinic acid inside droplet. The results are expressed with dimensionless parameters. Under 50 g/L succinic acid condition, the system with 0.1 mol/kg TOA showed that the molar flux decreases in proportion to the decrease of concentration gradient, while in the case of 0.5 mol/kg TOA Sh increases rapidly with time indicating the molar flux of succinic acid decreases relatively slowly compared to the decrease in concentration gradient.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.6
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• pp.683-688
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• 2007

Total polyphenolic compounds, DPPH radical scavenging activity, superoxide dismutase (SOD), vitamin A, C, E, flavonoid and anthocyanin of Rubus coreanus Miquel during maturation were investigated to expand the utilization of Rubus coreanus Miquel as functional food material. Physiological activities of unripened, middle-ripened and ripened fruit of Rubus coreanus Miquel were examined. The ripened fruit included higher contents of total polyphenolic compound compared with those of the other sample groups, unripened and middle-ripened fruit. SOD of unripened, middle-ripened and ripened fruit were 59.15, 80.05 and 95.03%, respectively. Scavenging concentration ($SC_{50}$) of unripened and middle-ripened fruit for 0.4 mM DPPH (1,1-diphenyl 2-picryl hydrazyl) was 2.3 mg/mL by weight, but only 1.6 mg/mL for ripened fruit. The vitamin A content of the Rubus coreanus Miquel was found to be lower as the fruit ripened; however, vitamin E showed the reverse pattern. In addition Rubus coreanus Miquel is a fruit which has a high vitamin C content regardless of maturity. The flavonoid contents of Rubus coreanus Miquel were in order of ripened fruit ($49{\mu}m/mg$)>middle-ripened fruit ($16.4{\mu}m/mg)$>unripened fruit ($15.4{\mu}m/mg$). Also, the contents of anthocyanin in ripened fruit were $394.50{\mu}m/mg$, which were higher than those of middle-ripened ($12.43{\mu}m/mg)$ and unripened fruit ($7.89{\mu}m/mg$).

• Journal of Life Science
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• v.27 no.10
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• pp.1097-1103
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• 2017

For the artificial induction of the sexual maturation of Anguilla japonica, salmon pituitary extract (SPE) is continuously injected into females, and the eggs obtained from artificial sexual maturation are artificially fertilized with sperms and hatched. However, repeated injection of SPE in the abdominal cavity causes tremendous stress in females, which may prevent their complete sexual maturation and reduce the immune system function, ultimately resulting in death. In addition, the poor quality of the ovulated eggs can reduce the hatching and survival rate of larvae. In the present study, sexual maturation of females was induced by inserting an osmotic (OS) pump containing hormone analogs known to effectively induce sexual maturation into the abdominal cavity of female eels, and the effect of the OS pump on the induced sexual maturation was investigated. Our study results showed that the gonadosomatic index (GSI) was significantly higher in the fish subjected to SPE injection than those subjected to human chorionic gonadotropin (hCG), gonadotropin-releasing hormone analog (GnRHa), and methyl testosterone (MT) injections, either separately or in combination. In addition, a histological analysis showed that the oocytes in the SPE OS pump groups were more mature (entered the nuclear shift stage) than those in the other groups. These results suggest that an osmotic pump containing hormone analogs can be used to induce sexual maturation in female A. japonica artificially.