• Journal of Ginseng Research
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• v.21 no.3
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• pp.209-213
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• 1997

Sesquiterpenes of Korean ginseng (Panax ginseng C.A. Meyer, KG) and American ginseng (Panax quinquefolium, AG) were Isolated by simultaneous distillation and extraction (SDE) with 30% methanol and n-hexane or adsorption using C18 Sep-Pak . The sesquiterpenes in KG and AG were compared each other by using TLC and GC/MS. Thin layer chromatogram of KG gave 4~5 spots of terpenes colored by vanillin-sulfuric acid, while AG did one major spot. Total ion chromatogram of KG showed about 30 peaks of sesquiterpene having molecular weight 204. Among these, 9 components such as alloaromadendrene, germacrene B, isocaryophyllene, $\alpha$-neoclovene, ${\gamma}$-muurolene and $\beta$-panasinsene together occupied 81.5% of total sesquiterpenes identified. In AG, however, only 3 components, i.e., isocaryophyllene, $\beta$-bisabolene, $\beta$-sesquiphellandrene occupied 79.3% of total sesquiterpenes identified. Especially isocaryophyllene was a dominant component of AG occupying 56.6%. Eight sesquiterpenes, including alloaromadendrene, germacrene B and $\alpha$-humulene, were not detected in AG. These results indicate that sesquiterpenes could be used as indices for the chemical difference between KG and AG.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.23 no.3
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• pp.152-160
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• 1997

It has been used that fluorinated compounds could be applied to Make-up products. It is that fluorinated compounds are hydrophobicity, lipophobicity and homophobicity. These fluorinated compounds are reported to form a highly protective and effective film against most aggressive chemical and physical agents. In this study we maed a success to formulate the new type of lipstic using perfluoropolymethylisopropylether with low molecular weight which is long wearing and comfortable to use. This PPIE was adsorbed more than 90% in this experiment and formed the well-balanced gel networks even if the selected PPIE is 100% volatile at room temperature. On the basis of the adsorption of PPIE, we developed the new type lipstick, which was highly-lip feeling and had long wearing and non coloration. And these characteristics were verified by actual consumer test.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.213-213
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• 2012

We first confirm the tautomerization of 2-thiazoline-2-thiol on Ge (100) surface using CLPES and DFT calculation. We clearly confirmed that there exist two different molecular structures (we well show in our poster) in C 1s, N 1s, and S 2p CLPES spectra. Moreover, we obtained two plausible adsorption structures using DFT calculation which are that one is s-dative bonded structure and the other is SH dissociated-N-dative bonded structure although their stabilities are different on Ge (100) surface. We will investigate this interesting result for the confirmation of tautomerization of 2-thiazoline-2-thiol molecule adsorbed on Ge (100) surface.

• Bulletin of the Korean Chemical Society
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• v.31 no.7
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• pp.1973-1975
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• 2010

The electronic and adsorption structure of o-phthalaldehyde (OPA) on the H-Si(100) surface was investigated by using Near Edge X-ray Fine Structure (NEXAFS) and high resolution photoemission spectroscopy (HRPES). We confirmed that the OPA grown on the H-Si(100) surface showed good dependency with about 60 degree tilting angle using NEXAFS and a single O 1s peak by using HRPES. Hydrogen atom passivated on the Si(100) surface was found to be a seed for making one dimensional organic line that uses a chain reaction as the H-Si(100) surface was compared with the hydrogen free Si(100) surface.

• Bulletin of the Korean Chemical Society
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• v.28 no.10
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• pp.1777-1780
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• 2007

The synthesis of well-defined dendrons based on aliphatic polyether dendritic cores and glassy polystyrene peripheries is described. The synthetic route involves a combination of living anionic polymerization and a stepwise convergent method consisting of iterative Williamson etherification and hydroboration/oxidation reactions. On the basis of molecular weight, as characterized by gel permeation chromatography (GPC), the first generation dendron (Generation-1) shows a random coil conformation like a linear polystyrene, while higher generations (Generation-2 and 3) reveal globular forms in solution.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1539-1542
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• 2005

Self-assembled monolayers (SAMs) formed by the adsorption of alkanethiols, $HS(CH_2)_nX$, where X is an organic functional group, onto gold surfaces have attracted widespread interest as templates for the fabrication of molecular and biomolecular microstructures. Previously photopatterning has been thought of as being restricted to the micron scale, because of the wellknown diffraction limit. So, we have explored a novel approach to nanofabrication by utilizing a femtosecond laser coupled to a near-field scanning optical microscope (NSOM).

• Journal of Microbiology and Biotechnology
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• v.10 no.4
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• pp.539-543
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• 2000

A new bacteriocin, named lacticin 10790, was purified from Lactococcus lactis subsp. cremoris KFCC 10790 by sequential adsorption, immobilized metal-affinity, cation-exchange, and $C_{18}$ reverse-phase chromatographies. The molecular mass of the bacteriocin was estimated to be between 3,000 and 3,500 Da. Lacticin 10790 showed a broad antimicrobial spectrum against many gram-positive bacteria. The bacteriocin was stable to heat and in the pH range between 2 and 6. Lacticin 10790 was destroyed by digestion with proteases and exhibited a bactericidal mode of action. An amino acid composition analysis of purified lacticin 10790 revealed a high concentration of hydrophobic amino acids. The N terminus of the bacteriocin was found to be blocked, upon analysis by Edman degradation. The results suggest that lacticin 10790 is a class I bacteriocin.

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.275-280
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• 2001

Bacteriocin J105 is a proteinaceous inhibitory substance produced by Latococcus latis subsp. lactis j105 isolated from Kimchi. Bacteriocin J105 was purified to homogeneity by the pH-dependent adsorption-desorption method and reverse-phase HPLC from the culture broth of Lactococcus lactis subsp. lactis J105. Purification of bacteriocin J105 resulted in a 1.47-fold increase in the specific activity and the recovery was 1.5%. Its molecular mass measured by the electrophoretic pattern in the sodium, dodecyl sulfate polyacrylamide gel was about 3.4 kDa. It was stable at $121^{\circ}C$ for 15 min at pH between 2 and 4. However, at pH above 5, bacteriocin was rapidly inactivated. Twenty-one residues from the N-terminal portion of bacteriocin J105 were sequenced using sequence analysis of lantibiotics. Bacteriocin J105 showed significant homology with known nisin A from lactic acid bacteria.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 1999.05a
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• pp.57-57
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• 1999

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.184-184
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• 2006

We have succeeded in the preparation of high molecular weight polybenzimidazoles by solution polycondensation of 3,3'-diaminobenzidine tetrahydrochloride with isophthalic acid, terephthalic acid, or with their derivatives using polyphosphoric acid both as solvent and as condensing agent. Also, we modified phosphoric acid into fluoroalkyl-phosphonic acids[F-PA]. The main reasons are as follows, first of all F-PAs are stronger acids than PA and alkylphosphonic acids which should promote proton hopping and transport. In addition, F-PA has weaker adsorption onto Pt which help to prevent electrocatalyst poisoning and promote higher oxygen reduction activity. The ionic conductivity of 85%-H3PO4 doped membranes show $10^{-2}\;Scm^{-1}\;to\;3{\times}10^{-2}\;Scm^{-1}\;at\;150^{\circ}C$ MEA with 2 %-added electrolyte shows slightly higher cell voltage than the others.