• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.5
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• pp.418-423
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• 2010

Carbon nanotubes (CNTs) were synthesized by Fe-catalytic chemical vapor deposition (CVD) method about $800^{\circ}C$. The influence of process parameters such as pretreatment conditions, gas flow ratio, processing time, etc on the growth of CNTs was investigated by field emission scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. Ammonia was added to acetylene source gas before and during the CNT growth. Different types of CNTs formed depending upon the processing condition. It was found that ammonia prevented amorphous carbons from adsorbing to the outer wall of CNT, resulting in purification of CNTs during CNT growth.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.277-278
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• 2008

Orthorhombic $LiMnO_2$(o-$LiMnO_2$) has attracted public attentions as a cathode materials of Lithium ion battery because it has low cost and high theoretical discharge capacity of 285mAh $g^{-1}$. In our study, o-$LiMnO_2$ is synthesized by quenching method. To verify their phase structure, X-ray diffraction is accomplished. Test cells are assembled to check electrochemical characteristics using acquired o-$LiMnO_2$ cathode and carbon anode. Charge/Discharge cycling was carried out for 50cycles. And impedance was measured at 1, 2, 5, 10, 30, 50cycle. During cycle test, the max discharge capacity was recorded 139mAh $g^{-1}$ at 10cycle.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.10a
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• pp.237-240
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• 2002

Amino terminated polyetherimide(ATPEI) has been synthesized by bisphthalic anhydride arid m-phenylenediamine, after that characterized by differential scanning calorimetry(DSC), thermogravimetric analyzer(TGA). Fourier transform (FT-IR) spectroscopy and gel permeation chromatography(GPC). ATPEI was blend to improve the toughness of bisphenol-A type epoxy resin which was cured by nadic methyl anhydride(NMA). The fracture toughness and the molphology of the toughened epoxy resin was evaluated. The toughness of ATPEI modified epoxy resin was higher than that of the PEI modified epoxy resin. In addtion, carbon fiber/ATPEI modified epoxy resin composites were fabricated and the mechanical properties of the resulted composites were investigated.

• Carbon letters
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• v.2 no.2
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• pp.105-108
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• 2001

In this work, the activated carbons (ACs) with high micropores were synthesized from the polystyrene (PS) with KOH as activating agent. And the influence of activation temperature on porosity of the ACs studied was investigated. The porous structures of ACs were characterized by nitrogen adsorption at 77K using BET and D-R equations, and MP and BJH methods. The weight loss behaviors of the samples impregnated with KOH were also monitored using thermogravimetric analyzer (TGA). As a result, it was found that the samples could be successfully converted into ACs with well-developed micropores. From the results of pore size analysis, it was confirmed that elevated activation temperature does lead to the formation and deepening of microstructures without significant change in mesostructures. A thermogravimetric study showed that KOH could suppress the thermal decomposition of the sample, resulting in the increase of carbon yields.

• Korea-Australia Rheology Journal
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• v.21 no.3
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• pp.185-191
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• 2009

Polystyrene/multi-walled carbon nanotube (PS/MWCNT) composites were prepared by the use of latex technology. The monodisperse PS latex was synthesized by an emulsifier-free emulsion polymerization from styrene/potassium persulfate/water system in the presence of ethanol. The MWCNTs were first treated with acid mixture to eliminate impurities, dispersed in deionized water driven by ultrasonicator, and then mixed with the PS latex. From these mixtures, PS/MWCNT composites were prepared by freeze-drying and subsequent compression molding. In the small-amplitude oscillatory shear experiments, both complex viscosity and storage modulus increased with increasing MWCNT content. A pronounced effect of MWCNT content was observed, resulting in larger storage modulus and stronger yield behavior at low frequencies when compared to unmodified PS. It showed a transition from viscous to elastic behavior with increasing MWCNT content. Over the MWCNT content of 3 wt%, the storage modulus was higher than the loss modulus across all frequencies.

• Journal of Life Science
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• v.9 no.1
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• pp.81-83
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• 1999

2,4-Disubstituted nortropinone derivatives anticipated anticonvulsant activity were respectively synthesized by the reaction of N-substituted nortropinones, ethanol, 5N-NaOH and benzaldehyde ({TEX}$R_{1}${/TEX}CHO)

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.6
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• pp.521-525
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• 2004

Biodegradation of poly(ethylene carbonate) (PEC) and their terpolymers has been investigated in vitro. PEC has been synthesized with ethylene oxide (EO) and carbon dioxide, which is one of the greenhouse gases using Zinc glutarate has been used as catalyst Carbonate terpolymers have been prepared by the use of EO, cyclohexene oxide(CHO), and carbon dioxide. High biodegradability of PEC and terpolymers with EO. has been observed. Very low biodegradation of poly(propylene carbonate) (PPC) and poly(cyclohexene carbonate) (PCHC) has been shown. The weight loss, FT-IR and SEM have been employed to characterize biodegradability.

• Bulletin of the Korean Chemical Society
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• v.28 no.9
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• pp.1545-1548
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• 2007

This paper discusses the racemic and stereoselective synthetic route for novel 4'α -methyl and 6'α -methyl analogues of abacavir. The quaternary carbon at the 4'-position of carbocyclic nucleoside was installed successfully via a Claisen rearrangement. The stereocontrolled construction of a methyl group in the 6'α - position was directed through the Felkin-Anh rule. A Bis-vinyl compound 9 was cyclized successfully using Grubbs' catalyst II to provide a carbocycle nucleus for the target compound. The synthesized compound 15 showed moderate anti-HIV activity (EC50 = 10.67 μM, MT-4 cell lines).

• Macromolecular Research
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• v.10 no.4
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• pp.181-186
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• 2002

The displacement of carbon black to polypyrrole as a catalyst supporter in the fuel electrode of a direct methanol fuel cell was investigated. Polypyrrole was obtained as a black powder by the chemical polymerization of pyrrole with three different oxidants. The synthesized polypyrroles were pasted on carbon paper and transformed to the fuel electrodes with electrochemically deposited platinum. The prepared fuel electrode was assembled and mounted in a unit cell using a membrane and cathodic electrode film. In comparison with the carbon black fuel electrode, the performance of the unit cell was analyzed in relation to the state of the catalyst, the type of oxidant, and the morphology of the polypyrrole powder.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.611-611
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• 2013

In this study, iron oxide nanoclusters layer (Nc) was prepared onto functionalized silicon substrate by wet method. The amine-terminated SAM fabricated on silicon substrate (APTMS/Si) was carried out by UV-treatment and immersed into the FeCl3/HCl aqueous solution. Then, Nc were immobilized onto oxidized SAM silicon substrate (SAMs/Si) through electrostatic interaction between cationic Nc and anionic SAMs/Si. This catalytic layer (Nc/SAMs/Si) was used to grow carbon nanotubes (CNTs). The characterization results clearly show that the well-graphitized CNTs were synthesized by using functionalized silicon substrate as a template having appropriate density of catalyst. These consequences show that SAM containing template is important to achieve the effective layer of catalyst to synthesize CNTs.