• 항공우주시스템공학회지
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• 제14권4호
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• pp.25-31
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• 2020

The development of manufacturing technology for braided composites has led to farther extension of the applications in aerospace structures. Since the mechanical characteristics of braided composites are affected by various materials and manufacturing parameters, it is important to determine the parameters required to appropriately design the braided composite structures. In this study, we proposed a geometric model of RUC (repeating unit cell) for 2D braided composites, and predicted the mechanical properties according to the change of fiber volume fraction, fiber filament size, braiding angle, and gap between adjacent yarns by the yarn slicing technique and stress averaging method. Finally, we analyze the characteristics of mechanical properties according to each manufacturing parameter of the braided composite material.

• Advances in Traditional Medicine
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• 제9권2호
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• pp.192-199
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• 2009

Bioactivity-directed isolation has led to the isolation of (-)-ent-costunolide (1) as the major active compound from Hepatostolonophora paucistipula. This compound (1) was determined by spectroscopic data interpretation. This sesquiterpene lactone (1) inhibited the growth of the dermatophytic fungus Trichophyton mentagrophytes ATCC 28185, (4 mm inhibition zone at $15{\mu}g$/disc), cytotoxic activity to murine leukaemia cell lines ATCC CCL 46 P 388D1 ($IC_{50}$ 687 ng/ml, at $0.075{\mu}g$/disk), BSC monkey kidney cell lines (100% of well at $15{\mu}g$/disk) and antiviral activity to Herpes simplex virus (0.25 mg/ml, 100% of well at $7.5{\mu}g$/disk) and Polio virus (0.125 mg/ml, 100% of well at $3.75{\mu}g$/disk). These results suggest that (-)-ent-costunolide (1) has potential antimicrobial and cytotoxic agents.

• Archives of Pharmacal Research
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• 제24권4호
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• pp.312-315
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• 2001

Repeated column chromatographic separation of the $CH_{2}Cl_{2}$ extract of Artemisia stolonofera (Asteraceae) led to the isolation of a triterpene (I), a sesquiterpene (II), two aromatic compounds (III and IV) and a benzoquinone (V). Their structures were determined by spectroscopic means to be simiarenol (I), (1S,7S)-1 $\beta$-hydroxygermacra-4(15),5, 10(14)-triene (II), 3'-methoxy-4'-hydroxy-trans-cinnamaldehyde (III), vanillin(IV) and 2,6-dimethoxy-1,4-benzoquinone (V), respectively. Among these products, compound V showed significant cytotoxicity against five human tumor cell lines in vitro, A549 (non small cell lung adenocarcinoma), SK-OV-3 (ovarian), SK-MEL-2 (skin melanoma), XF498 (CNS) and HCT15 (colon) with ED_{50}$ values ranging from 1.33~4.22${\mu}g/ml$.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.300.1-300.1
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• 2013

반사방지막 코팅(Anti-reflection coating)은 태양전지(Solar cell), 발광다이오드(LED) 등의 반사율을 낮추어 효율을 증대시키기 위하여 사용되고 있다. 본 실험에서는 유리 기판 위에 실리콘 타겟을 이용한 Reactive magnetron sputtering 장비를 활용하여, 50~100 mTorr의 높은 공정 압력(High pressure)에서 증착하여 SiO2 반사방지막 코팅층을 형성하였다. Ellipsometer를 이용하여 SiO2 박막층의 굴절률(Refractive index)을 측정한 결과, 공정 압력에 따라 SiO2 박막이 다양한 굴절률을 가지는 것을 확인할 수 있었다. 또한, UV-Vis spectrometer를 이용하여, 450~600 nm 파장에서의 반사율(Reflectance)과 투과율(Transmittance)을 측정하여 비교, 분석하였다. 나아가 증착된 SiO2 반사방지막을 비정질 실리콘 박막 태양전지에 적용하여 효율 향상 효과를 실험하였다. 이를 활용하여 낮은 굴절률을 갖는 반사방지용 SiO2 코팅층을 형성하여 태양전지의 광 변환 효율을 상승 시킬 수 있고, 발광다이오드의 광 추출 효율을 증가시킬 있을 것으로 여겨진다.

• Preventive Nutrition and Food Science
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• 제9권3호
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• pp.265-269
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• 2004

Prunus mandshurica var. glabra Nakai (Rosaceae) is widely distributed in South Korea and bears a fruit with a bitter and astringent taste. An ethyl acetate-soluble extract of Prunus mandshurica was found to exhibit significant cytotoxicity against human leukemia cell lines. Bioassay-directed fractionation of this extract using an MTT(3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) cell proliferation assay as a monitor led to the isolation of the bioactive compounds. Two compounds, 1 and 2 were subsequently found to mediate cytotoxicity against U937, human monocytic leukemia cells. The 50% growth inhibitory concentrations ($IC_{50}$/) of compounds 1 and 2 on U937 were 40 and 62 $\mu\textrm{g}$/mL, respectively.

• Archives of Pharmacal Research
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• 제28권12호
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• pp.1341-1344
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• 2005

Bioassay-guided fractionation of $CHCl_{3}$ extract from the fermentation broth of a sponge Mycale plumose-derived actinomycete Saccharopolyspora sp. nov., led to the isolation of two known prodigiosin analogs - metacycloprodigiosin (1) and undecylprodigiosin (2). These compounds exhibited significant cytotoxic activities against five cancer cell lines: P388, HL60, A-549, BEL­7402, and SPCA4. This is the first report on the significant cytotoxicity of metacycloprodigiosin (1) against human cancer cell lines.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.392.2-392.2
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• 2002

Cytotoxic activity against the P388 cell line was seen in a crude extract of Anisotome lyallii. A bioactivity guided isolation led to the isolation of a deterpene. which displayed strong Cytotoxic activity against the P388 cell line (IC50 2.3 $\mu$g/ml), as well as antimicrobial activity against Bacillus subtilis. The structure of de terpene 1 was elucidated by spectroscopic methods. (omitted)

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.264.2-264.2
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• 2003

The bark of Alnus japonica has been used of fever, hemorrhage and diarrehea in oriental traditional medicine. This research was focused on the anti-inflammatory activities of diarylheptanoid from the bark of A. japonica on RAW 264.7 cell line. Phytochemical examination of the bark of Alnus japonica Steudel had led to the isolation of ten diarylheptanoids. To investigate the anti-inflammatory activities of these compounds, nitric oxide and PGE2 production inhibitory in IFN-${\gamma}$, LPS stimulated RAW 264.7 cell were examined. (omitted)

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.190.1-190.1
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• 2003

A bioassay-guided fractionation of the stem bark extract of Eucommia ulmoides Oliver (Eucommiaceae) led to the isolation of three iridoid constituents, genipin (1), geniposide (3), geniposidic acid (4) as well as (${\pm}$)-guaiacylglycerol (2) and fatty acid mixtures as active ingredients of the extract responsible for the antitumoral property. The EtOAc soluble part and BuOH soluble part of the extract demonstrated a significant inhibition on the proliferation of cultured human tumor cells such as A549 (non small cell lung), SK-OV-3 (ovary), SK-MEL-2 (melanoma), XF498 (central nerve system) and HCT-15 (colon) in vitro, whereas the remaining water soluble part exhibited a poor inhibition. (omitted)

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.202.2-202.2
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• 2003

A bioassay-guided fractionation of the whole extract of Viscum album (a parasitic plant : Loranthaceae) led to the isolation of two triterpenoidal components, oleanolic acid (1), ${\beta}$-amyrin acetate (2), homoflavoyadorinin B (3) as well as large quantity of free fatty acid mixtures as active ingredients of the extract responsible for the antitumoral property. The EtOAc soluble part and BuOH soluble part of the extract demonstrated a significant inhibition on the proliferation of cultured human tumor cells such as A549 (non small cell lung), SK-OV-3 (ovary), SK-MEL-2 (melanoma), XF498 (central nerve system) and HCT-15 (colon) in vitro, whereas the remaining water soluble part exhibited a poor inhibition. (omitted)