• Journal of Ginseng Research
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• v.33 no.3
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• pp.165-176
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• 2009

Korean ginseng, which contains ginsenosides and polysaccharides as its main constituents, is orally administered to humans. Ginsenosides and polysaccharides are not easily absorbed by the body through the intestines due to their hydrophilicity. Therefore, these constituents which include ginsenosides Rb1, Rb2, and Rc, inevitably come into contact with intestinal microflora in the alimentary tract and can be metabolized by intestinal microflora. Since most of the metabolites such as compound K and protopanaxatriol are nonpolar compared to the parental components, these metabolites are easily absorbed from the gastrointestinal tract. The absorbed metabolites may express pharmacological actions, such as antitumor, antidiabetic, anti-inflammatory, anti-allergic, and neuroprotective effects. However, the activities that metabolize these constituents to bioactive compounds differ significantly between individuals because all individuals possess characteristic indigenous strains of intestinal bacteria. Recently, ginseng has been fermented with enzymes or microbes to develop ginsengs that contain these metabolites. However, before using these enzymes and probiotics, their safety and biotransforming activity should be assessed. Intestinal microflora play an important role in the pharmacological action of orally administered ginseng.

• Journal of Photoscience
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• v.6 no.2
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• pp.61-65
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• 1999

The fluorescence properties and photoisomerization behavior of 1-(9-anthryl)-2-(n-quinolinyl)ethene (n-AQE, n=2-4) have been investigated in various solvents. t-3-AQE is strongly fluorescent, but does not accomplish photoisomerization, similar to parent hydrocarbon compound, t-1-(9-anthryl)-2-phenylethene (t-9-APE) or t-1-(9-anthryl)-2-(1-naphthyl)ethene (t-1-ANE). Fluorescence and photoisomerization oft-2-AQE and t-4-AQE are strongly affected by solvent polarity. Dependence of fluorescence quantum yield on the solvent polarity is moderate for t-2-AQE and large for t-4-AQE. In nonpolar solvent (in n-hexane), they exhibit relatively strong fluorescence, but do not isomerize to cis isomer on irradiation, even if inefficient isomerization is observed for t-4-AQE. However, as solvent polarity increases, their fluorescences become weak with efficient photoisomerization to corresponding cis isomer. Intramolecular charge-transfer excited state is presumed to contribute to photoisomerization. The S$_1$ decay parameters were found to be solvent-dependent due to the charge-transfer character of lowest S$_1$ state. In polar solvents, the activation barrier to twisting is reduced enhancing the isomerization of r-2-AQE and t-4-AQE in the singlet manifold.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1992.11a
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• pp.110-113
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• 1992

This paper presents the results on experiments of relative dielectric constant dielectric loss, conductivity change and breakdown voltage of the L.D.P.E. mixed with Dodecyl Alcohol. The frequency range is 0.1 - 20 MHz and temperature, 20 - 80 $^{\circ}C$. Dielectric properties were similar to those of nonpolar polymers. Until $60^{\circ}C$ the conductivity value of compound was decreased with temperature increasment. And, its breakdown voltage was measured higher, about 3-4KV, than that of the pure L.D.P.E.. Also the amount of remnants of DA in the compounds were considered.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.679-682
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• 2008

The particle which has two different characteristics on both sides is called Janus particle which is emerging as a key material in microscale transport systems. For example, if one hemisphere has polarity and the other does not, then nonpolar sides would attract each other so that a complex cluster is formed. Thus, this fascinating material can be used as an element of twisting ball panel display, complex micro-scale clusters, drug delivery unit, and active detecting beads. The keywords in developing Janus particle are size and uniformity. Former researches solved uniformity but downsizing still remains a problem. There are three methods to generate small size particles in microchannels: co-flowing, cross-flowing, and elongational flows. In this research, we generate Janus particles smaller than 10-${\mu}$m in diameter using elongational flow in microchannels. And we use UV initiator with Hydrogen UV source to solidify micro size particles. One hemisphere of the particle is coated with rhodamin for visualization.

• Journal of the Korean Chemical Society
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• v.14 no.2
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• pp.161-168
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• 1970

In order to obtain the more effective evidence, supporting the hypothesis which have been previously described by former report that pepsin (EC 3.4. 4.1) forms a hydrophobic bond with the nonpolar side chain of its substrate, the inhibitory effect of carboxylic acids(from formic acid to iso-butyric acid) on the activity of pepsin to the synthetic dipeptide, N-Carbobenzoxy-L-glutamyl-L-tyrosine, was discussed. The kinetic study showed that the inhibition by carboxylic acids was competitive. The Kidecreased with increasing size of the inhibitor molecule. The $-{\Delta}F^{\circ}$increased linearly with increasing number of carbon atoms in the hydrocarbon chain of the inhibitor. It was confirmed that the hydrophobic bond between more than one side chain of amino acid residues(phenylalanine) in the binding region of the active center of pepsin and the side chain of amino acid residues in the substrate was formed as the first step of its enzymic mechanism. The inhibitory effect of carboxylic acids was due to the competition of the hydrocarbon group of the carboxylic acids with the side chain of the substrate for the hydrophobic binding site(the side chain of phenylalanine) of the pepsin.

• Journal of Information Display
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• v.11 no.3
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• pp.95-99
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• 2010

A series of new dielectric polymers with phenyl, epoxy, and carboxylicacid functional groups was prepared via free-radical polymerization. The effect of such dielectric polymers with various functional groups on the performance of OTFT was investigated. The nonpolar groups of terpolymer made the surface of the dielectric layer more hydrophobic and improved the crystal growth of pentacene on the gate insulator, resulting in higher mobility. By controlling the functional group, the electric characteristics of OTFT performance was varied, with $0.00017-0.15\;cm^2/V{\cdot}s$ mobility.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.602-602
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• 2013

산화아연(ZnO)은 직접 천이 와이드 밴드갭(3.37 eV)과 큰 excitation binding energy (60 meV)를 갖는 II-VI 반도체로 광촉매, light emitting diodes (LED), dye-sensitized solar cell 등의 여러 가지 분야에서 각광받고 있는 물질이다. ZnO는 열역학적으로 안정한 polar terminated (001)면과 nonpolar low-symmetry (100)면을 갖으며 (100)면이 (001)면보다 더 안정하기 때문에 (100)방향의 일차원구조가 쉽게 합성된다. 이러한 일차원 구조는 빛의 산란을 유도하여 더 많은 빛의 흡수를 야기 시킬 뿐만 아니라 일차원 구조를 따라 효율적인 전하 전달을 가능하게 한다. 본 연구에서는 일차원 구조의 장점을 살리면서 더 넓은 표면적을 갖는 hierarchical ZnO nanowire 구조를 수열합성법과 스퍼터링증착법을 이용하여 합성하였다. Hierarchical ZnO nanowire는 SEM, TEM을 이용하여 구조를 관찰하였고 UV-visable spectroscopy를 이용하여 일차원 구조의 ZnO nanowire와의 absorbance, transmittace 차이를 확인하였다.

• Journal of the Korean Graphic Arts Communication Society
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• v.28 no.2
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• pp.13-30
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• 2010

Existing domestic ink market had some problem because of dependence on CPP import, increasing cost, competitive price. For this reason, previous speed of research and developments are very slow. Therefore, develop the new waterborne type of non-chlorine resin, enhance the nation's position with manufacturing outstanding products. Through this thesis, the purpose is mix the polar resin and non-chlorine resin with many proportion and manufacturing better product than existing resin. Pilot production samples have run the test of adhesion, transparency, water resist and resist high pressure car washing. In conclusion, this thesis found that mix acryl Urethane resin and Non-Chlorine resin is the optimum condition.

• Journal of Ginseng Research
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• v.1 no.1
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• pp.29-32
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• 1976

Succinate dehydrogenase was activated by ethyl acetate extract from the methanol extract of white ginseng previously treated with petroleum ether and ethyl ether to remove all highly nonpolar components, and the residual aqueous solution from the ethyl acetate extraction. Also, all of the extracted fractions of red ginseng except the ether extract gave positive results. On the contrary to some suggestions by other workers that alkaloids of ginseng may enhance the succinate degydrogenase activity, our results show that the alkaloids may have exhibited some inhibitory eject on this enzyme.

• Journal of Ginseng Research
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• v.1 no.1
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• pp.19-24
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• 1976

Ginseng extracts were frnctionelod into several fractions with carious organic solvents, and the effects of these fractions on the activity of aminoacyl-tRHA synthetase was examined. Fractions which showed positive effect on the activity of the aminoacyl-tRNA synthetase were obtained both from white ginseng and red ginseng. The total methanol extract of whit ginseng and the ether extract from the total methanol extract of red ginseng gave Positive results. Therefore it may be Presumed that the Positive components have rather nonpolar nature.