• Bulletin of the Korean Chemical Society
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• v.13 no.5
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• pp.551-553
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• 1992

An efficient and very short synthesis of epoxy alcohol 5, a key intermediate for leukotriene synthesis, was described. The key reaction involves the regioselective benzylidene acetal formation from methyl 5,6,7-trihydroxyheptanoate 1.

• Journal of the Korean Chemical Society
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• v.55 no.5
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• pp.824-829
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• 2011

In Fischer-Tropsch Synthesis, because of few reactants ($H_2$, CO), scarce operating parameters affected on efficiency especially the selectivity of products. In this research, effect of operating parameters on the selectivity of Co-Mn-$TiO_2$ Fischer-Tropsch synthesis catalyst were studied by design of experimental procedure and Taguchi method. According to this research, interactions between operating factors have a crucial effect on light products selectivity. Among these interactions, (temperature${\times}$feed ratio) has the main influence on light hydrocarbons selectivity. It was concluded that temperature and feed ratio ($H_2$/CO) were the most integral operating parameters for much greater selectivity of light hydrocarbons.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.616-620
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• 2001

The objectives of this study are to investigate the suitability of various coal fly ashes and incineration ashes for zeolite synthesis. Zeolite P and hydroxysodalite are produced from coal fly ash and paper sludge incineration ash. When soluble and acid-soluble materials in incineration fly ash are removed by the water washing or acid washing before hydrothermal synthesis, hydroxysodalite can be produced. The factors to make solid-liquid separation difficult are the calcium component and the unburned carbon in ash.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.3
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• pp.258-261
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• 2006

The addition of zeolite particles enhances the stability of mRNA molecules in a cell-free protein synthesis system. When $20{\mu}g/{\mu}L$ of zeolite (Y5.4) is added to a reaction mixture of cell-free protein synthesis, a substantial increase in protein synthesis is observed. The stabilizing effect of zeolite is most dearly observed in an in vitro translation reaction directed by purified mRNA, as opposed to a coupled transcription and translation reaction. Upon the addition of zeolite in the in vitro translation reaction, the life span of the mRNA molecules is substantially extended, leading to an 80% increase in protein synthesis. The effect of zeolite upon the mRNA stability appears be strongly related to the cation exchange (potassium to sodium) reaction. Our results demonstrate the possibility of modifying this biological process using heterogeneous, non-biological substances in a cell-free protein synthesis system.

• Bulletin of the Korean Chemical Society
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• v.26 no.6
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• pp.880-881
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• 2005

• Journal of the Korean Chemical Society
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• v.54 no.2
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• pp.181-182
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• 2010

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.566-570
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• 2011

An efficient and general synthesis of bibenzyl derivatives bearing pyranyl rings was achieved by ethylenediamine diacetate-catalyzed reactions of 3,5-dihydroxybibenzyl with ${\alpha},{\beta}$-unsaturated aldehydes in moderate yields. These reactions provided naturally occurring compounds 1 and 2 in single step reaction. As an application of this methodology, biologically interesting natural bauhinol D (8) was synthesized by a convergent sequence from readily available benzaldehyde and benzyl phosphonate.

• Bulletin of the Korean Chemical Society
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• v.30 no.11
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• pp.2563-2566
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• 2009

The first total synthesis of naturally occurring prorepensin with a bis-geranylated chalcone has been achieved by a convergent sequence. The key strategy involved in the synthesis of prorepensin was chalcone formation by aldol condensation of the corresponding geranylated acetophenone with geranylated benzaldehyde.

• Journal of the Korean Ceramic Society
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• v.31 no.11
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• pp.1283-1292
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• 1994

Ultra-fine $\beta$-SiC powders were fabricated by self-propagating high temperature synthesis process (SHS) using chemical furnace. The dependences of the C powders with different surface areas, the molar ratios of C/Si, the weight ratios of chemical fuel content, and pellet diameter-size on synthesis were investigated. Compositional and structural characterization of these powders was carried out by scanning electron micrograph and X-ray diffraction. The $\beta$-SiC powders which had C/Si mole ratio=1.05, 3 times chemical fuel contents, and pellet diameter=20 mm were optimum for synthesis efficiency. By optimizing process-variables, it is possible to fabricate $\beta$-SiC powders which have little secondary phases ($\alpha$-SiC).

• Bulletin of the Korean Chemical Society
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• v.28 no.9
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• pp.1493-1498
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• 2007

In this work, alkyl methacrylate-based microgels were synthesized by an experimental design method, and their sebum absorption characteristics were investigated. The results of fractional factorial experimentation indicated that the cross-linking agent content, solvent content, and stirring speed were the main parameters in the synthesis of the microgels. The suitable synthesis conditions were determined by the response surface design method. Through a study of the monomer and solvent effects, it was confirmed that the microgel shows the highest sebum absorption ratio when t-butyl methacrylate is used as a monomer or when acetone is used as a solvent. The optimal microgel synthesis conditions for cosmetic application were determined, and the resulting microgel had a mean particle size of 4.7 μm and a sebum absorption ratio of 435%.