• Environmental Mutagens and Carcinogens
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• v.26 no.2
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• pp.35-40
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• 2006

Background: Inorganic arsenic is a human carcinogen that can target the liver, but its carcinogenic mechanisms are still unknown. Inorganic arsenic induces a spectrum of tumors including hepatocellular carcinoma in mice. Methods: Pregnant C3H mice were supplied with drinking water containing 50 ppm sodium arsenite during their pregnancy. The protein expression profile in the liver of 0.5-day-old. male offsprings exposed transplacentally to sodium arsenite was analyzed using protein 2D gel electrophoresis followed by mass spectrometry (MALDI-TOF). Results: Expression of proteins such as hydroxymethylglutaryl-CoA synthase mitochondrial precursor (HMG-CoA synthase), ${\beta}$-actin (cytoplasmic 1) and apolipoprotein A-IV precursor (Apo-AIV) were induced in mouse liver by sodium arsenite, while uricase (urate oxidase), guanine nucleotidebinding protein beta subunit 2-like 1 (RACK1) and fructose-bisphosphate aldolase B (Aldolase 2) were down-regulated. Summary: Expression of proteins that have been implicated in carcinogenesis, such as HMG-CoA, ${\beta}$-actin, and RACK1, was regulated in the liver of mice transplacentally exposed to inorganic arsenic.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 2000.06a
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• pp.151-163
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• 2000

A polymerized organic-inorganic complexation route is introduced for the synthesis of oxide ceramic powders. Polyvinyl alcohol was used as the organic carrier for precursor ceramic gel. Porous and soft powders, which have a high specific surface area, were obtained after calcinating the aerated precursors. The PVA content and its degree of polymerization had a significant influence on the homogeneity of the final powder. In particular, attrition milling process with the porous powder resulted in ultra-fine particles. In the case of the preparation of cordierite powder, nano-size powder, which has a high specific surface area of 181 ㎡/g, was obtained by the milling process. The complexation route was also applied to the synthesis of unstable phase in room temperature like beta-cristobalite, high temperature form of silica.

• Journal of the Korean Ceramic Society
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• v.34 no.9
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• pp.993-1001
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• 1997

The (0.8PPV+0.2DMPPV) copolymer and silica/borosilicate composites were synthesized by sol-gel process. The organic-inorganic hybrid solution was prepared by using of (0.8PPV+0.2DMPPV) copolymer precursor solution as a raw material for organic components and TEOS and TMB for glass components. Then by drying the solution in vacuum at 5$0^{\circ}C$ for 7days and subsequent heat treatment in vacuum at 15$0^{\circ}C$~30$0^{\circ}C$ for 2h~72h with heating rate of 0.2$^{\circ}C$/min and 1.8$^{\circ}C$/min, the organic-inorganic composites were synthesized. Microstructural evolution of the composites was characterized by DSC, IR spectrocopy, UV/VIS spectroscopy, and TEM. Elimination of the polymer precursor and degradation of the polymer were observed by DSC and Si-O and trans C=C absorption peaks were identified by IR spectra. The polymer was found to be successfully incorporated into the glass matrix and it was confirmed by the absorption peaks from the polymer in the UV/VIS spectra and the TEM results. The absorption peak of the composites was found to shift toward short wavelength side compared to that of the pure polymer and the amount of the blue shift increased with increasing the heat treatment temperature and heat treatment time and with decreasing the heating rate.

• Proceedings of the Korean Vacuum Society Conference
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• 1996.06a
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• pp.31-31
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• 1996

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.178-191
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• 2003

OMC is essentialiy necessary compound in sun goods as organic UV protecting products. But the skin-trouble problem is raising because of skin penetration of OMC. In this study, non-capsulated pure OMC was compared with Organic-Inorganic-Nano-hybrid OMC for skin penetration force and SPF degree. Organic- Inorganic Nano-Hybrid OMC is OMC trapped in the pore of the mesoporous silica synthesized by the sol-gel method after OMC is nanoemulsified in the system of the hydrogenated Lecithin/ Ethanol/caprylic/capric triglyceride/OMC/water. OMC- nano- emulsion was obtained by a microfluidizing process at 1000bar and then micelle size in the nanoemulsion solution is 100-200nm range. Mesoporous silica nano-hybrid OMC was prepared by the process; surfactant was added in dissolved OMC-Nanoemulsion, then the rod Micelle was formed. OMC-nanoemulsion was capsulated in this rod Micelle and then silica precursor was added in the OMC-nanoemulsion solution. Through the hydrolysis reaction of the silica precursor, mesoporous silica concluding OMC-Nanocapsulation was obtained. The nano-hybrid surface of this OMC-Nanoemulsion-Inorganic system was treated with polyalkyl-silane compound. OMC-Mesoporous silica Nano-hybrids coated with polyalkyl-silane compound show the higher sun protecting factor (SPF Analyzer: INDEX 10-15) than pure OMC and could reduce a skin penetration of OMC. The physico-chemical properties of these nano-hybrids measured on the SPF index, partical size, strcture, specific surface area, pore size, morphology, UV absorption, rate of the OMC dissolution using SPF Analyzer, Laser light scattering system, XRD, BET, SEM, chroma Meter, HPLC, Image analyzer, microfluidizer, UV/VIS. spectrometer.

• Applied Chemistry for Engineering
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• v.16 no.5
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• pp.628-634
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• 2005

Zirconia-alumina polymer precursor was prepared from zirconium acetylacetonate (ZA). paluminium nitrate (AN), polyethylene glycol (PEG), and ethyl alcohol via an organic-inorganic solution technique. The thermal properties and viscosity of the polymer precursor were measured by differential scanning calorimetry (DSC), thermograbimetric analyzer (TGA), and dynamic viscometer. The vigorous exothermic reaction with volume expansion occurred at $140^{\circ}C$. The volume expansion was caused by abrupt decomposition of the organic group in metal compounds and the metal ions-PEG reaction. The evidences for these reactions were confirmed by FT-IR and $^{13}C$ solid NMR results. The peak intensity at N-O, O-H and C=C decreased with increasing temperature. This indicated that the decomposition of metal compounds and the metal ions-PEG reaction occurred during the vigorous exothermic reaction. At $800^{\circ}C$ for 2 h, the porous powders transformed to the crystalline $ZrO_2-Al_2O_3$ composites.

• Journal of the Korean Ceramic Society
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• v.30 no.1
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• pp.34-40
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• 1993

ORMOSIL was synthesized with inorganic precursor, TEOS and organic precursor, PDMS, and the variation of composite properties according to the concentration of HCl, solvent content and reaction time were studied. As the concentration of HCl increased, condensation reaction was well proceeded and more regularly distributed network was observed. Increase in reactivity was found with the amount of solvent, and composite had a tendency of forming more porous microstructure as reaction time was increased, which had no influence on the bonding degree.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.727-729
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• 2007

Inorganic-organic hybrid polymer provides various advantages including low-temperature process, high dielectric constant and direct photo-patterning. The hybrid dielectric was synthesized by the sol-gel process in which an acid-catalyzed solution of Si alkoxide and Zr alkoxide was used as a precursor. The electrical performance of transistors with hybrid dielectric was investigated.

• Journal of the Korean Ceramic Society
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• v.50 no.6
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• pp.460-465
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• 2013

Plate-shaped inorganic particles are coated onto a stainless steel substrate by the electrophoretic deposition of a precursor slurry which includes the inorganic particles of $Al_2O_3$ and polymer resin in mixed solvents to mimic the abalone shell structure, which is a composite of plate-shaped inorganic particles and organic interlayer binding materials with a layered orientation. The process parameters of the electrophoretic deposition include the voltage, coating time, and conductivity of the substrate. In addition, the suspension parameters are the particle size, concentration, viscosity, conductivity, and stability. We prepared an organic-inorganic composite coating with a high inorganic solid content by arraying the plate-shaped $Al_2O_3$ particles and electrophoretic resin via an electrophoretic deposition method. We analyzed the effect of the slurry composition and the electrophoretic deposition process parameters on the physical, mechanical and thermal properties of the coating layer, i.e., the thickness, density, particle orientation, Young's modulus and thermogravimetric analysis results.

• Journal of the Korean Ceramic Society
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• v.25 no.1
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• pp.49-53
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• 1988

Polycarbosilane was synthesized from the pyrolysis of polydimethylsilane, which is dechlorinated from dimethyldichlorosilane. The pyrolysis temperature was varied at 280-480$^{\circ}C$ for 2 hours. FT-IR, FT-NMR and GPC measurement were studied on the residue inside the reaction crucible and viscous solution inside the cooling zone respectively. From the viscous solution in the cooling zone at 420$^{\circ}C$, the synthesis of polycarbosilane wa well detected.