• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.353-355
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• 2004

YBaCuO thick films were fabricated by plasma enhanced chemical vapor deposition, and the crystallinity and the superconducting properties were investigated. The growth temperature to obtain the thick films was decreased by around $150^{\circ}C$ due to plasma enhancement. The zero resistivity temperatures for films grown at $590^{\circ}C$ and $620^{\circ}C$ were 55 and 80 K, resistively.

• Journal of Pharmaceutical Investigation
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• v.37 no.4
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• pp.211-216
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• 2007

The bark of Alnus japonica has been used for the treatment of fever, hemorrhage and diarrehea in oriental traditional medicine. Recently, it was revealed that the diarylheptanoids from the bark of Alnus japonica possess anti-inflammatory activity and are expected to be applicable for atopic dermatitis. In this study, oregonin, one of major active components in the bark of Alnus japonica, was developed in the form of semisolid formulations for topical delivery. Oregonin was incorporated into four ointment bases: O/W cream, W/O cream, hydrophilic ointment and lipophilic ointment. Oregonin release from all formulation prepared was evaluated. Franz cell method and immersion method were employed to characterize the release patterns of drug from each formulation based on solvent availability. O/W cream showed a better release profile than the other formulations when evaluated with Franz cell method with an order of O/W cream, hydrophilic ointment, W/O cream and lipophilic ointment. In the immersion method, hydrophilic ointment showed the greatest release rate at times 1 hour exceeding compared to other bases with an order of hydrophilic ointment, O/W cream, W/O cream and lipophilic ointment. Hydrophilicity and solvent availability of formulation seems to significantly influence the release rate of oregonin from ointment bases. In this study, we successfully characterized the oregon in ointment and found that o/w cream is a promising formulation for the topical delivery of oregonin.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1408-1410
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• 2001

The 0.96$MgTiO_3$-0.04$BaTiO_3$ ceramics were prepared by the conventional mixed oxide method. The structural properties were investigated with sintering temperature and composition ratio by XRD, SEM and EDS. According to the X-ray diffraction patterns of the 0.96$MgTiO_3$-0.04$BaTiO_3$ ceramics, the hexagonal $BaMg_6Ti_6O_{19}$ and ilmenite $MgTiO_3$ structures were coexisted. In the case of the 0.96$MgTiO_3$-0.04$BaTiO_3$ ceramics sintered at 1325$^{\circ}C$, dielectric constant, quality factor and temperature coefficient of resonant frequency were 23.95, 70,200, -55.8ppm/$^{\circ}C$, respectively.

• Proceedings of the KIEE Conference
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• 2008.10a
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• pp.117-118
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• 2008

The $V_{1.85}W_{0.15}O_5$ thin films deposited on Pt/Ti/$SiO_2$/Si substrates by RF sputtering method exhibited fairly good TCR and dielectric properties. It was found that film crystallinity, dielectric properties, and TCR properties were strongly dependent upon the annealing temperature. The dielectric constants of the $V_{1.85}W_{0.15}O_5$ thin films annealed at $400^{\circ}C$ were 38.11, with a dielectric loss of 1%, respectively. Also, the TCR values of the $V_{1.85}W_{0.15}O_5$ thin films annealed at $400^{\circ}C$ were about -3.45%/K.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.90-92
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• 2004

Suspension effect has been studied by using superconductor of BiPbSrCaCuO ceramics containing $Ag_2O$. It has been cleared that $Ag_2O$ acts as pinning center which plays an important role to the suspension effect. Magnetic repulsive force which affects a superconductor located in magnetic flux from toroidal magnet has been investigated. It has been concluded that the suspension effect arises from the interaction between the pinning effect and the diamagnetic effect.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.206-207
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• 2005

Display 소재로서 유전체나 격벽재 실링재로 사용되고 있는 frit는 PbO를 주성분으로 갖는 유리가 사용되고 있다. PbO 성분이 함유된(50$\sim$85%) 구성소재는 최근 RoHS 나 WEEE 등의 환경규제 실행에 직면해 있으며, 대체재료의 개발을 위한 많은 연구가 진행되고 있다 PbO 성분을 대체할 성분으로는 $Bi_2O_3$ 계, BaO-ZnO 계, $P_2O_5$ 계 등의 성분이 주요성분으로 이루어져 있으며, PbO 성분을 함유한 유리의 저융점, 저유전율, 고 투과율, 내산성, 내전압, 팽창계수 matching 등의 특성들에 부합되는 재료를 개발하기 위해 많은 노력을 기울이고 있다. 본 연구에서는 SnO-$P_2O_5$ 계 유리 조성을 선택하여 $R_2O_3$의 치환 및 용융분위기의 조절에 따른 저융점 유리로서의 특성과 효과에 대하여 고찰하였다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.53-53
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• 2009

박막태양전지의 투명전도막으로 응용이 기대되는 ZnO 박막을 원격 유도결합플라즈마를 이용하여 고속으로 증착활 수 있는 공정기술을 개발하기 위하여 기판온도, 가스조성 플라즈마 파워와 같은 공정변수에 대하여 실험하였다. 실험결과 증착속도는 소스유량을 고정한 경우, 온도가 증가할수록 감소하며, $H_2O$ 유랑과 압력이 증가할수록 증가하다가 포화되는 경향을 나타내었다. 기판온도 $150\;^{\circ}C$와 플라즈마 출력 200 W의 조건에서 ZnO의 증착속도는 500 nm/min 이상의 높은 증착속도를 나타내었으며, 전기적 광학적 특성 또한 우수한 것으로 나타났다. 또한 ZnO 박막의 물성은 구조에 민감하게 의존하였으며, 이러한 구조는 공정조건에 의하여 제어가능 함을 알 수 있었다. 자세한 연구결과는 학회에서 발표할 예정이다.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1774-1776
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• 1999

The (1-x)$MgTiO_3-SrTiO_3$ (x=0,0.1,0.2,0.3) ceramics were prepared by the conventional mixed oxide method. The structural properties were investigated with sintering temperature and composition ratio by XRD, SEM and DT-TGA. Increasing the sintering temperature from $1300^{\circ}C$ to $1600^{\circ}C$, second phase was decreased and grain size was increased. The average grain size of the $0.8MgTiO_3-0.2SrTiO_3$ ceramics sintered at $1600^{\circ}C$ were $3.61{\mu}m$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.281-281
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• 2010

In this study, ZnO nanorod arrays are grown on organic substrates by hydrothermal method which requires a low temperature, simple process, and no vacuum. The structure properties of ZnO nanorods were examined by field emission scanning electron microscopy and X-ray diffraction. To detect the optical transmission, ultraviolet visible spectrophotometer was also used. From results, the ZnO nanorods were grown the horizontal growth on the organic substrates had the length of over $10\;{\mu}m$. After deposition of ZnO seed layer, the ZnO nanorod arrays had uniformity orientation and length.

• Korean Journal of Pharmacognosy
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• v.23 no.1
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• pp.14-19
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• 1992

A mixture of acylglucosyl sterols together with ${\beta}-sitosterol$, ${\beta}-sitosterol\;3{\beta}-O-glucoside$ and fatty acids was isolated from the roots of Caragana chamlagu as their acetate forms and the structure elucidated by chemical and spectroscopic means. The major acylglucosyl sterol was ${\beta}-sitosteryl\;3-O-[6'-O-oleoyl]-{\beta}-D-glucopyranoside$ while the minor components were $6'-O-palmitoyl-\;and\;6'-O-stearoyl-{\beta}-D-glucosyl$ sitosterol congeners. The isolation and structure elucidation of these acylglucosyl sterols are reported for the first time from the genus Caragana.