• Bulletin of the Korean Chemical Society
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• v.34 no.11
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• pp.3488-3490
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• 2013

• Polymer(Korea)
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• v.38 no.2
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• pp.232-239
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• 2014

Poly(lactic acid)(PLA) nanocomposites containing various nanofillers were synthesized using the solution intercalation method. Organically modified bentonite clay (NSE), octadecylamine-graphene oxide (ODA-GO), and an NSE/ODA-GO complex were utilized as nanofillers in the fabrication of PLA hybrid films. PLA hybrid films with varying nanofiller contents in the range of 0-10 wt% were examined and compared in terms of their thermomechanical properties, morphologies, and oxygen permeabilities. Transmission electron microscopy (TEM) confirmed that most of the NSE and ODA-GO nanofillers were dispersed homogeneously throughout the PLA matrix on the nanoscale, although some agglomerate NSE/ODA-GO complex particles were also formed. Among the three nanofillers for PLA hybrid films, the NSE/ODA-GO complex showed the best improvement in film thermal stability. In contrast, NSE and ODA-GO exhibited the best improvement in tensile mechanical properties and oxygen barrier properties of the PLA hybrid films, respectively.

• Bulletin of the Korean Chemical Society
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• v.25 no.6
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• pp.829-832
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• 2004

The pure product of 2,3-diaminophenazine was prepared by the enzyme-catalyzed reaction of ophenylenediamine-$H_2O_2$-horseradish peroxidase and characterized by UV/Vis spectroscopy, IR spectroscopy and NMR spectroscopy. The electrochemical behaviour of 2,3-diaminophenazine on the glassy carbon electrode was studied. The interaction between 2,3-diaminophenazine and deoxyribonucleic acid was studied by cyclic voltammetry method and UV/Vis spectroscopy, which indicated that the interaction between them is intercalation. The influence of reacting time was also studied. The binding ratio of the 2,3-diaminophenazine-DNA complex is calculated to be 1 : 2 and the binding constant is to be $5.07{\times} 10^3L{\cdot}mol^{-1}$ at room temperature.

• Journal of the Korean Ceramic Society
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• v.22 no.6
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• pp.15-20
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• 1985

In the course of cement hydration it was found that the addition of polyvinyl alcohol(contracted as PVA. here after) only in the cement paste could more influence on the set-retardation the depression of heat evol-ution rate than that of montmorillonit only or PVA-montmorillonie intercalation complex (PMIC) due to the effective adsorption of PVA on cement particles. The improved mechanical strength by addition of montmorillonite and PMIC was observed remarkably up to 0.05wt% due to the decrease of macro-pores caused by lowed viscosity or the acceleration of hydration reaction.

• Journal of the Mineralogical Society of Korea
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• v.19 no.2 s.48
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• pp.123-128
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• 2006

Beidellite, a member of the dioctahedral smectite group, was synthesized hydrothermally from dickite. Organophilic [DEACOOH]-beidellite intercalation complex was formed by the cation exchange reaction between synthetic Na-beidellite and [DEACOOH]Br. The products dried in high vacuum were treated with various organic solvent such as methanol, ethanol, acetone, ether, acetonitrile and caprolactam in order to determine the swelling behaviour of the prepared complexes. After drying under high vacuum, basal spacing of [DEACOOH]-beidellite shows 15.1 ${\AA}$, and it changed to 19.4, 29.9, 15.9, 16.8, 14.8, 26.5 and 14.8 ${\AA}$ under distilled water, methanol, ethanol, acetone, ether, acetonitrile and caporlactam, respectively. Especially, the characteristics of the intercalation complexes and their swelling behavior of the synthetic beidellite and natural montmorillonite were compared.

• Bulletin of the Korean Chemical Society
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• v.17 no.11
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• pp.1004-1009
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• 1996

The interactions between a rod-coil liquid crystalline oligomer, ethyl 4-[4'-oxy-4-biphenylcarbonyloxy]-4'-biphenylcarboxylate with poly(ethylene oxide) (DP=12) (12-4) and LiCF3SO3 have been characterized by using Raman spectroscopy. Band assignments were made comparing the spectrum of 12-4 with those of the poly(ethylene glycol) monomethyl ether(PEGME) (Mw=550) and the ethyl-4'-hydroxybiphenyl-4-carboxylate (EHBPC), which are the coil and mesogen analogues, respectively. Analyzing characteristic bands of the 12-4-salt complex, we have found that the bands belonging to the coil and mesogenic units are changed in both intensities and frequencies. The spectral changes were interpreted from the viewpoint of the complexation between 12-4 and the Li+ ion. However, the possibility that the spectral changes in the mesogenic unit are not due to the complexation with the Li+ ion, but due to the conformational changes by the intercalation of nondissociated LiCF3SO3, is not ruled out.

• Polymer(Korea)
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• v.35 no.1
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• pp.47-51
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• 2011

In this study, illite, an environmental friendly, low cost, and high aspect ratio additive, was used to improve flame retardant property of epoxy and it was fluorinated to enhance dispersion of hydrophilic illite in hydrophobic epoxy by introducing hydrophobic functional groups. Fluorination of illite enhanced illite dispersion ill epoxy solution before curing and that in the complex after curing. These enhanced dispersions were attributed to the increased affinity of illite to hydrophobic epoxy solution induced by fluorination of illite and the increased intercalation of epoxy polymer or exfoliation of illite by epoxy curing. Hence, limited oxygen index(LOI) of fluorinated illite/epoxy complex increased by 24%, compared to that of epoxy, suggesting that the preparation of fluorinated illite/epoxy complex increased their flame retardant properties.

• Journal of the Korean Ceramic Society
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• v.38 no.5
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• pp.431-437
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• 2001

본 연구에서는 양이온 교환반응에 의해 Na-Mont와 R$_{11}$SO$_4$로부터 R$_{11}$SO$_4$-Mont 층간화합물을 합성한 후, 이 R$_{11}$SO$_4$-Mont 층간화합물을 다시 제 4차 유기 양이온인 (Et)$_4$N$^{+}$ 이온 및 (Bu)$_4$N$^{+}$ 이온과 반응시켜 그 거동을 살펴보았다. R$_{11}$SO$_4$-Mont를 (Et)$_4$N$^{+}$이온과 반응시켰을 대보다 (Bu)$_4$N$^{+}$ 이온과 반응시킨 경우에 좀 더 큰 층간거리가 얻어졌다. R$_{11}$SO$_4$-Mont를 (Et)$_4$N$^{+}$이온 및 (Bu)$_4$N$^{+}$과 반응시켜 얻은 층간화합물을 다시 아세토니트릴, 에탄올 및 디옥산과 팽윤반응을 수행한 결과 층간거리가 확장되었으나, 이는 Na-Mont를 R$_{11}$SO$_4$와 48시간 교환 반응시킨 후에 교환용액 하에서 얻은 R$_{11}$SO$_4$-Mont의 층간거리에 불과했다. 원소분석결과, R$_{11}$SO$_4$-Mont와 (Bu)$_4$N$^{+}$를 반응시킬 경우 반응이 반응식 b에 의거 진행되고, (Bu)$_4$N-Mont를 R$_{11}$SO$_4$와 반응시킬 경우에는 반응식 c에 의거 진행됨을 예측할 수 있었다.의거 진행됨을 예측할 수 있었다.

• Advances in nano research
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• v.10 no.4
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• pp.373-383
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• 2021

In this work, silver nitrate complexes of sulfanilamide-5-methyl-2-thiophene carboxaldehyde (SMTCA) ligand intercalated Zn/Al-layered double hydroxide [Ag-SMTCA-LDH] were synthesized for the potential application as an antimicrobial system. The SMTCA ligand was synthesized by reacting sulfanilamide and 5-methyl-2-thiophene carboxaldehyde in methanol and further complexation with silver nitrate metal ions [Ag-SMTCA]. The structural analyses of synthesized compounds confirmed an intercalation of Ag-SMTCA into Zn/Al-NO₃-LDH by flake/restacking method. SMTCA, Ag-SMTCA and Ag-SMTCA-LDH were characterized by ¹H nuclear magnetic resonance (¹H NMR) spectroscopy, Fourier-transform infrared (FTIR), ultraviolet-visible (UV-Vis) spectrophotometer, scanning electron microscopy (SEM) and transmission electron microscopy (TEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). It was found that Ag-SMTCA-LDH exhibited good antimicrobial activity against both gram-positive (Bacillus subtilis, [B. subtilis], Staphylococcus aures, [S. aureus]) and gram-negative (Escherichia coli, [E. coli], Pseudomonas aeruginosa [P. aeroginosa]) bacteria as well as excellent antioxidant activity.

• Journal of the Korean Electrochemical Society
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• v.1 no.1
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• pp.33-39
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• 1998

To AC impedance study was performed in this study on the interfacial reaction between organic electrolyte and amorphous tungsten oxides thin film, cathodically coloring oxide, prepared by e-beam evaporation method in the 1 M $LiClO_4/PC$ organic solution. The electrochemical reactions at the interface were analyzed by the transient method and the complex impedance spectroscopy. The impedance spectrums showed that the electro-chemical intercalation of lithium cations was consisted of the following three steps; the first step, the charge transfer reaction of lithium cation at the interface between amorphous tungsten oxides thin film and the organic electrolyte, the second step, the adsorption of lithium atom on the surface of amorphous tungsten oxides thin film, and then the third step, the absorption and the diffusion of lithium atom into amorphous tungsten oxides thin layer. The bleaching and the coloring characteristics of amorphous tungsten oxides thin film were explained in terms of thermodynamic and kinetic variables, the simulated $R_{ct},\;C_{dl},\;D$ and $\sigma_{Li}$ by CNLS fitting method. Especially it was found that the limiting values of electrochromic reaction were the molar ratio of lithium, y=0.167 and the electrode potential, E=2.245 V (vs. Li).