• Applied Biological Chemistry
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• 제49권1호
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• pp.25-29
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• 2006

하귤(Citrus natsudaidai Hayata)의 과피를 cold-press하여 얻어진 정유성분을 column chromatography, HPLC 및 TLC로 분리 정제하여 각 분획에 대하여 EBV활성화에 대한 억제효과를 측정하였다. Column chromatography로 정유성분의 분리를 시도하여 7개 의 peak$(F-I{\sim}VII)$를 얻을 수 있었다. 이것들을 TLC로 분석한 결과, 각각 단일 반점만을 나타냈으며 $R_f$값은 0.31, 0.13, 0.13 0.78, 0.79, 0.69, 0.84이었다. 7개의 peak중에서 F-I, II 및 F-IV 등 3개의 peak에 대하여 HPLC분석을 한 결과 F-I 및 F-II는 단일 peak이며 retention time은 F-I이 3분, F-II는 2.5분이었다. 그러나 F-IV는 2개의 peak가 나타났으며 retention time은 각각 2분과 4.5분이었다. 4.5분에 나타난 peak는 극히 적은 면적으로 보아 극소량의 물질이어서 앞서의 TLC분석에서 나타나지 많았던 것으로 생각된다. $F-I{\sim}F-VII$에 대한 EBV활성화에 대한 억제효과 측정은 Raji cells을 이용하여 간접형광 항체법으로 실시했다. 억제율은 F-VI가 $82.3{\pm}1.3%$으로 가장 높았으며 다음이 F-I$(80.4{\pm}1.6%)$ > F-II$(77.2{\pm}0.9%)$ > F-III$(75.0{\pm}1.2%)$ > F-IV$(74.1{\pm}1.0.%)$ > F-V$(71.0{\pm}1.1%)$ > F-VII$(70.2{\pm}1.2%)$의 순으로 모두 70% 이상의 억제율을 나타냈다. 이상의 결과는 하귤과피에는 발암 promotion 억제활성성분이 존재한다는 것을 시사한 것이다.

• 마이크로전자및패키징학회지
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• 제18권2호
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• pp.57-62
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• 2011

염료 감응 태양 전지(Dye-Sensitized Solar Cells: DSSCs)의 에너지 변환효율은 $TiO_2$ 전극의 입자 크기, 구조 및 표면 형태에 의존한다. 높은 비표면적을 갖는 나노 크기의 아나타제 $TiO_2$는 많은 염료를 흡착할 수 있어 변환효율을 증가 시킨다. 또한 전극 내부에서 태양광의 산란을 증가 시키면, 염료가 태양광을 흡수하는 양이 증가하여 효율이 증가할 수 있다. 수열 합성법으로 합성한 $TiO_2$ 분말의 크기는 15-25 nm이고, 결정상은 구형의 anatase 상이다. 0.4 ${\mu}m$의 $TiO_2$ 산란입자를 합성한 나노 크기의 $TiO_2$ 분말에 혼합하여 전극을 제조하고, DSSCs를 제작한 후 변환효율을 측정하였다. 10% 의 산란 입자가 포함된 DSSCs는 단락전류 3.51 mA, 개방전압 0.79 V, 곡선인자 0.619로 6.86%의 변환 효율을 나타 내었다. 산란 입자의 영향으로 단락전류밀도는 11% 증가하였고, 효율은 0.77% 증가하였다. 산란 입자가 포함되지 않은 DSSCs 보다 산란 입자가 전극으로 들어온 태양광을 산란시켜 전자-홀 쌍의 생성을 증가 시키고, 전자가 전극을 따라 이동하는 경로가 감소하여 효율이 증가하였다. 10% 이상의 산란 입자는 전극 내부에 입자 크기의 큰 기공을 증가 시켜 효율이 감소하였다.

• 한국자원식물학회지
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• 제6권1호
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• pp.25-32
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• 1993

Many plants, which collected from Korea, were applied to antitumor and cytotoxic screeing tests against sarcom 180 a ascitec in mice, V-79 KB and P388 cultured cells. The results are summarixed as follows:1) The total packed cell volum method has been used for the antineoplastic screening for from natural higher plants in Korea. By this method, we have found out that the root, leaf and stem of Tripterygiu, regelii Spragne & Taketa having strong antineoplastic activity and also Rumex Japonicus Houtt. Eragrositis ferru-ginea Beauv. and Patrinia scabio-saefolia Fischer showed significant activity to anticancer tumor while cynanchum wilfordii Hemsley, and Rosa polyantha Sieb. et Zacc. showed slight activity to antitumor. 2) Among the 13 tested plants, the root and stem of Tripterygium regelii Spragne & Taketa and Amethystanthus excisus Nakai showed strong antitumor activity by the V79 cytotoxic cell screening test. 3) Twelve plants, which are glowing in mountainous area of Korea tested to anticancer activity. From the results, Eragrositis ferru-ginea Beauv., Angelica gigas Nakai, Geranium sibiricum L., Patrinia scabio-saefolia Fisher, Cynanchum wilfordii Hemsley, and Rubia akane Nakai have been proved to be anti-cancer plants by using P388 cell cultured method. 4) Tripterygiu, resgelii Spragne & Taketa, Eragrositis ferru-ginea Beauv., Patrinia scabio-saefoli Fisher, Cynanchum wilfordii Hemsley and Rasa polyantha Sieb. et Zacc., var. genuina Thunb. showed strong anti-tumor activity both total packed cell volume method and Cytotoxicity method.

• 대한전자공학회논문지
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• 제22권4호
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• pp.92-100
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• 1985

P형 Si기판에 N에피층을 성장시키고 Si-AR막 계면에서 고정양전하밀도(Qss)를 높임으로써 전지의 에미터 표면영역을 N'전하축적층으로 나타낸 새로운 형태의 N'N/P HLE 태':1전지 를 제 작하였다. 제작된 전지의 종류로는 AR막으로 SiOr층을 이용한 OCI전지와 Si,N,/sioxynitride층을 이응한 NCI전지로 구분하였다. 전지의 AR막내 Qss분포는 커패시턴스-전압 측정을 통해 조사하였으며 이로부터 NCI전 al (Qss=1.79~ 1.84$\times$1011cm-2) 가 OCI전 지 (Qss=3.03~ 4.40$\times$1011cm-1) 에 비 해 로면 전 하축 적 층 이 효과적 으로 나타남을 알 수 있었다. JCR할로겐 램프로 100mW/cm2의 인공조명을 만들어 효율특성을 분석한 결과 유효수광면적에 대한 평균(최대)변환효율이 OCI전지에서 15.18(15.46)%, NCI전지에서 16.31(17.07%)로 나타났다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 D
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• pp.1895-1897
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• 1999

This paper describes the fabrication and performance characterizations of the CIGS$(CuInGaSe_2)$ solar cells and its prototype module. The CIGS cell and module were fabricated on the sodalime glass$(5\times5cm^2)$ by the well known three stage co-evaporation and series connection followed by patterning process. respectively. The developed minimodule with active area of $14.7cm^2$ showed 6.0% solar efficiency($V_{oc}$=3.2V, $I_{sc}$=79.8mA, FF=34.6%) in AM 1.5 condition.

• Bulletin of the Korean Chemical Society
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• 제29권8호
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• pp.1495-1498
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• 2008

$TiO_2$ nanopowders were synthesized by new sol-gel combustion hybrid method using acetylene black as a fuel. The dried gels exhibited autocatalytic combustion behaviour. $TiO_2$ nanopowders with an anatase structure and a narrow size distribution were obtained at 400-600 ${^{\circ}C}$. Their crystal structures were examined by powder Xray diffraction (XRD) and their morphology and crystal size were investigated by scanning electron microscopy (SEM). The crystal size of the nanopowders was found to be in the range of 15-20 nm. $TiO_2$ powders synthesized at 500 ${^{\circ}C}$ and 600 ${^{\circ}C}$ were applied to a dye solar cell. An efficiency of 5.2% for the conversion of solar energy to electricity ($J_{sc}$ = 11.79 mA/$cm^2$, $V_{oc}$ = 0.73 V, and FF = 0.58) was obtained for an AM 1.5 irradiation (100 mW/$cm^2$) using the $TiO_2$ nanopowder synthesized by the sol-gel combustion hybrid method at 500 ${^{\circ}C}$.

• 전기학회논문지
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• 제63권1호
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• pp.76-79
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• 2014

We report Zinc oxide (ZnO) nanorods synthesis and electrochemical luminescence (ECL) cell fabrication. The ECL cell was fabricated using the electrode of ZnO nanorods and Ru(II) complex ($Ru(bpy)_3{^{2+}}$) as a luminescence materials. The fabricated ECL cell is composed of F-doped $SnO_2$ (FTO) glass/ Ru(II)/ZnO nanorods/FTO glass. The highest intensity of the emitting light was obtained at the wavelength of ~620 nm which corresponds to dark-orange color. At a bias voltage of 3V, the measured ECL efficiencies were 5 $cd/m^2$ for cell without ZnO nanorod, 145 $cd/m^2$ for ZnO nanorods-$5{\mu}m$, 208 $cd/m^2$ for ZnO nanorods-$8{\mu}m$ and 275 $cd/m^2$ for ZnO nanorods-$10{\mu}m$, respectively. At a bias voltage of 3.5V, the use of ZnO nanorods increases ECL intensities by about 3 times compared to the typical ECL cell without the use of ZnO nanorods.

• BMB Reports
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• 제28권1호
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• pp.1-5
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• 1995

The effect of 6-sulfooxymethyl benzo(a)pyrene (SMBP) on conformational changes of calf thymus DNA was investigated. As SMBP is a strong electrophile, the covalent binding of SMBP to DNA should distort three dimensional conformation of DNA at the binding sites. A formaldehyde-unwinding methods were used to determine the rate of DNA denaturation. The increase in absorbance at 251nm was detected by addition of formaldehyde following treatment with SMBP. SMBP changed supercoiled DNA to relaxed and linear DNA as determined by electrophoresis, which was similar to the change in DNA due to in vitro treatment with benzo(a) pyrene diol epoxide. Treatment with SMBP completely denatured DNA under alkaline conditions. However, DNA was nicked or partially denatured under neutral condition. The absorption band of DNA was increased by the treatment with SMBP in V79 cells, which may be explained by the formation of stabilized SMBP-DNA adduct.

• Asian Pacific Journal of Cancer Prevention
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• 제15권18호
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• pp.7521-7526
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• 2014

Radioprotective effects of amentoflavone were investigated by examining cell viability, apoptosis, cell cycling concentrations of intracellular ROS (reactive oxygen species), and relative mitochondrial mass by flow cytometry after $^{60}Co$ irradiation. Pretreatment with amentoflavone 24 hours prior to 8 Gy $^{60}Co$ ${\gamma}$-ray irradiation significantly inhibited apoptosis, promoted the G2 phase, decreased the concentration of ROS and mitochondrial mass. These results collectively indicate that amentoflavone is an effective radioprotective agent.

• 한국자원식물학회지
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• 제6권1호
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• pp.45-51
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• 1993

Many plants collected at Japan, China, Korea, Imdonesia and South America were applied to antitumor and / or cytotoxic screening tests against Sarcoma 180 ascites in mice and / or V-79, KB, P388 cultured cells. On the course of these screening tests, alcoholic extracts of Forsythia viridissima (Oleaceae), Eurycoma longifolia(Simaroubaceae), Rubia cordifolia and R. akane(Rubiaceae), Cissampelos pareira and Abuta concolor (Menispermaceae), Nardostachys chinensis (Valerianacese), Mansoa alliaceae (Bignoniaceae), Casearia sylvestris (Flacourtiacear), Maytenus ilicifolia (Celastraceae), Hedychium coronarium (Zingiberaceae), Croton palanostigma(Euphorbiaceae), Cocculus trilobus(Menispermaceae), Ginkgo biloba(Ginkgoaceae), Alpinia galanga and Cucculus zanthorrhiza(Zingiberaceae), Evodia rutaecarpa(Rutaceae), and Periploca sepium(Asclepiadaceae) showed significant activity and their active principles were clarified. In this paper, a few antitumor substances in above plants are introduced.