• The Korea Journal of Herbology
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• v.33 no.3
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• pp.37-43
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• 2018

Objectives : Butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA) were well known as anti-oxidant, but they were limited to use because of toxicity. So, many studies are being done to develope natural anti-oxidant. Total phenolic and flavonoid contents along with total antioxidant capacity of the ethanolic extract of Plantaginis Herba (PH) were evaluated to explore the reliable and potential sources of novel natural antioxidants. Methods : Total polyphenol contents and total flavonoid contents in PH ethanol extract were determined by colorimetric method. And DPPH(1.1-diphenyl-2-picrylhydrazyl), ABTS(2'-azino-bis (3-ethylbenzothiazoline-6-Surfonicacid)) free radical scavenging capacity and reducing power inhibition activities of PH ethanol extract were measured at 100, 500, 1000, $5000{\mu}g/m{\ell}$ concentrations by spectrometric assay. Results : The total polyphenol contents and total flavonoid contents of the extract were 161.99 mg/g, 144.05 mg/g, respectively. Also, DPPH, ABTS free radical scavenging capacity and reducing power of PH ethanol extract in treated concentrations (100, 500, 1000, $5000{\mu}g/m{\ell}$) increased dose dependently. In particular, DPPH free radical scavenging capacity of PH ethanol extract from $500{\mu}g/m{\ell}$ was significantly increased compared to positive control (BHA). ABTS free radical scavenging capacity of PH ethanol extract from $1000{\mu}g/m{\ell}$ was significantly higher than BHA. Also, reducing power showed that PH ethanol extract from $500{\mu}g/m{\ell}$ was significantly increased compared to BHA. Conclusions : These results suggest that PH ethanol extract has effects to scavenge free radicals, thus PH has potential and applicable benefits for development of materials and products to have anti-oxidation functions.

• Journal of Ocean Engineering and Technology
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• v.6 no.2
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• pp.55-70
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• 1992

트림변화에 의해서 발생하는 선체 구조응답을 고찰, 계산 결과를 요약하였다. 본 고찰로 부터 같은 크기의 선수, 선미 트림상태일지라도 많은 차이를 보였다. 이에는 중량분포의 효과가 특히 크게 작용함을 밝히었다.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.10a
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• pp.305-308
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• 2001

Powder injection molding (PIM) uses the shaping advantage of injection molding but is applicable to metals and ceramics. This process combines a small quantity of polymer with an inorganic powder to form a feedstock that can be molded. After shaping, the polymeric binder is extracted and the powder is sintered often to near-theoretical densities. Accordingly, PIM delivers structural materials in a shaping technology previously restricted to polymers. The process overcomes the shape limitations of traditional powder compaction, the costs of machining, the productivity limits of isostatic pressing and slip casting, and the defect and tolerance limitations of casting. The 17-4 PH stainless steel powders with average diameter of $10{\mu}m$ were injection-molded into flat tensile specimens. Sintering of the compacts was carried out at the various temperatures ranging from 900 to $1350^{\circ}C$. Sintering behavior of the compacts and tensile properties of sintered specimens were investigated.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.2
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• pp.141-154
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• 1996

Intrinsic layers of homoepitaxial InP grown by the hydride vapor phase epitaxy (VPE) technique were investigated by Fourier-transform photoluminescence(FTPL) and variable temperature Hall measurements. The effect of process variables (i.e., source zone temperature and inlet mole fractions of HCl and $PH_{3}$) on the backgroudn impurity levels was investigated. The background carrier concentration was found to decrease with decreasing source zone temperature and increasing HCl, but was relatively independent of $PH_{3}$ for the range of mole fraction studied. The presence of background donors and acceptors was clearly verified in the FTPL spectra, and the major impurities were tentatively identified as Si donors and Zn acceptors as well as some unidentified acceptors.

• Clinical and Experimental Pediatrics
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• v.52 no.5
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• pp.619-621
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• 2009

Paroxysmal hemicrania (PH) is rare in children and not widely recognized. It is characterized by pain attacks and associated symptoms and signs similar to those experiencing cluster headaches, but the features have a shorter effect, are more frequent, and respond completely to indomethacin. Some patients with PH may experience slight pain across the midline. There are only four cases of bilateral PH in the literature and it is very rare in children. Here, I report the case of a 10-year-old female with bilateral PH diagnosed by the typical symptoms along with the favorable response to indomethacin therapy.

• KSBB Journal
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• v.28 no.3
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• pp.170-176
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• 2013

The purpose of this study was to determine optimum condition of Pavlova lutheri and Phaeodactylum tricornutum. Detailed studies were carried out on the effects of various wavelengths of light-emitting diodes (LEDs), light intensities and air flow rations. For the Pa. lutheri, cell growth rates and maximum cell concentrations were similar regardless of wavelengths and air flow rates. Among the different light intensities, cell concentration increased when light intensity of red LED increased. For Ph. tricornutum, red LED was found to be the most effective light source, and light intensity of 3,100 Lux resulted in the most effective for the cultivation of Ph. tricornutum. Different air flow rates were tested to overcome shading effects due to denser cell concentration in the solution. Aeration of 0.8 vvm was determined to be the optimum aeration rate for the cultivation of Ph. tricornutum. Especially, five and two times greater cell concentrations of Pa. lutheri and Ph. tricornutum, respectively, were observed when air was applied.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.41-42
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• 2001

The chemopreventive effect of tea against 2-amino-l-methyl-6-phenylimidazo［4, 5-b ］pyridine (PhIP)-DNA adduct formation and its mechanism were studied. Rats were exposed to freshly prepared aqueous extracts of green tea (3% w/v) as the sole source of drinking water for 10 days prior to administration with a single dose of PhIP (10 mg/kg body wt) by oral gavage. PhIP-DNA adducts in the liver, colon, heart, and lung were measured using the $^{32}$ P-postlabelling technique.(omitted)

• Bulletin of the Korean Chemical Society
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• v.24 no.11
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• pp.1671-1674
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• 2003

The effects of amine donors ($a:NH_2,\;b:NMe_2,\;c:NMePh,\;d:NPh_2$) and conjugation length on the molecular hyperpolarizabilities of a series of dipolar molecules have been theoretically investigated by using CPHF/6-31G method. The first hyperpolarizabilities (${\beta}$) of p-nitrobenzene derivatives increase with the donor in the order, $NH_2\;<\;NMe_2\;<\;NMePh\;<\;NPh_2$, whereas slightly different order is observed in more conjugated derivatives, i.e., $NH_2\;<\;NPh_2\;<\;NMe_2\;<\;NMePh$. The result has been attributed to the extent of charge transfer and torsion angle. Moreover, the results show that "non-traditional" ${\pi}$-conjugation effect exists in small compounds and decreases as the conjugation length between donor and acceptor increases.

• Textile Coloration and Finishing
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• v.17 no.6 s.85
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• pp.36-41
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• 2005

The effects of low temperature plasma treatment on the properties of three types of foams, polyurethane(PU), injection phylon(IP), and phylon(PH) that used for footwear mid-sole were examined. The change of surface properties of foams were characterized by electron scanning microscope, contact angle measurement, and universal testing machine. Adhesion was tested by T-peel tests of plasma treated foams/polyurethane adhesive joints. The contact angle of three types of foams were decreased dramatically with the plasma treatment time, specifically noticeable in the case of phylon(Ph). It has shown the relationship with the contact angle of phylon(PH) and the distance between electrode and samples. The peel strength of foams were increased with the increase of plasma treatment time.

• Journal of Korea Foundry Society
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• v.13 no.2
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• pp.163-167
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• 1993

Mechanical and chemical properties of the 17-4PH have been investigated after recycled melting. As the result, it has been ascertained that the change of Ni, Cu, Nb, C amount affects the mechanical and chemical properties. It is important to minimize contamination of impurities and to control the amount of Ni, Cu, Nb, C.