• Carbon letters
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• v.18
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• pp.76-79
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• 2016

• Bulletin of the Korean Chemical Society
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• v.14 no.3
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• pp.367-370
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• 1993

• Bulletin of the Korean Chemical Society
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• v.8 no.6
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• pp.480-482
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• 1987

• Journal of Microbiology and Biotechnology
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• v.17 no.8
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• pp.1338-1343
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• 2007

Angiogenesis is an essential step in tumor progress and metastasis. Accordingly, small molecules that inhibit angiogenesis would appear to be a promising way to cure angiogenesis-related diseases, including cancer. In the present study, we report that streptochlorin, a small molecule from marine actinomycete, exhibits a potent antiangiogenic activity. The compound potently inhibited endothelial cell invasion and tube formation stimulated with vascular endothelial cell growth factor (VEGF) at low micromolar concentrations where it showed no cytotoxicity to the cells. In addition, streptochlorin inhibited TNF-${\alpha}$-induced $NF-{\kappa}B$ activation in the newly developed cell-based reporter gene assay. These data demonstrate that streptochlorin is a new inhibitor of $NF-{\kappa}B$ activation and can be a basis for the development of novel anti-angiogenic agents.

• Bulletin of the Korean Chemical Society
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• v.33 no.5
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• pp.1523-1526
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• 2012

In this work, we prepared activated multi-walled carbon nanotubes/polyacrylonitrile (A-MWCNTs/C) composites by film casting and activation method. Electrochemical properties of the composites were investigated in terms of serving as MWCNTs-based electrode materials for electric double layer capacitors (EDLCs). As a result, the A-MWCNTs/C composites had much higher BET specific surface area, and pore volume, and lower volume ratio of micropores than those of pristine MWCNTs/PAN ones. Furthermore, some functional groups were added on the surface of the A-MWCNTs/C composites. The specific capacitance of the A-MWCNTs/C composites was more than 4.5 times that of the pristine ones at 0.1 V discharging voltage owing to the changes of the structure and surface characteristics of the MWCNTs by activation process.

• Journal of the Korean Chemical Society
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• v.41 no.9
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• pp.443-448
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• 1997

Kinetics for the solvolyses of acyl chlorides and alkyl chlorides in hydroxylic solvent mixtures have been measured by conductometric method at various temperatures and pressures. The activation parameters (${\Delta}V^{\neq},\; {\Delta}H^{\neq},\; {\Delta}S^{\neq}$) were estimated from the rate constants. The reactivities of these reactions were also estimated from the correlation of the activation volumes with the activation entropies.

• Journal of the Korean Chemical Society
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• v.25 no.4
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• pp.214-218
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• 1981

Kinetic studies were carried out on urethane polymerization reaction of hydroxyl-terminated polybutadiene with isophorone diisocyanate under presence of Hexogen as solid additive. The rate was found to increase with the amount of Hexogen added. However the rate acceleration was not a catalytic effect but solely due to an increase of activation entropy. The reaction was a good 2nd order process with nearly constant activation energy of 8.4 kcal/mole.

• Carbon letters
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• v.20
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• pp.32-38
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• 2016

In this study, cellulose nanoplates (CNPs) were fabricated using cellulose nanocrystals obtained from commercial microcrystalline cellulose (MCC). Their pyrolysis behavior and the characteristics of the product carbonaceous materials were investigated. CNPs showed a relatively high char yield when compared with MCC due to sulfate functional groups introduced during the manufacturing process. In addition, pyrolyzed CNPs (CCNPs) showed more effective chemical activation behavior compared with MCC-induced carbonaceous materials. The activated CCNPs exhibited a microporous carbon structure with a high surface area of 1310.6 m²/g and numerous oxygen heteroatoms. The results of this study show the effects of morphology and the surface properties of cellulose-based nanomaterials on pyrolysis and the activation process.

• Journal of the Korean Chemical Society
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• v.30 no.2
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• pp.166-171
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• 1986

Hydrogen atom transfer reactions, $RNH_2+CH_3{\to}RNH+CH_4\;where\;R=H\;and\;CH_3$, were studied by MINDO/3 MO method. It is expected that stable complex may exist between $CH_3\;and\;NH_3$. Transition state characteristics and activation parameters including activation entropies have been determined. In cases of absolute and activation entropies, results are found to agree in general with ab initio and experimental values, wherever comparisions are possible.

• Journal of the Korean Chemical Society
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• v.64 no.3
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• pp.145-152
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• 2020

Flip-flop rate constants were measured by dithionite assay of NBD-PE fluorescence in DMPC/POPC vesicles made of various DMPC/POPC ratios. The activation energy, enthalpy, entropy, and free energy were determined based on the transition state theory. We found that the activation energy, enthalpy, and entropy increased as the amount of POPC increased, but the activation free energy was almost constant. These experimental results and other similar studies allow us to propose that the POPC molecules included in DMPC vesicles affect the flip-flop motion of NBD-PE in DMPC/POPC vesicles via increasing the packing order of the ground state of the bilayer of the vesicles. The increase in the packing order in the ground state seems to be a result of the effect of the overall molecular shape of POPC with a monounsaturated tail group, rather than the effect of the longer tail group.