• Bulletin of the Korean Chemical Society
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• v.31 no.2
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• pp.470-472
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• 2010

• Analytical Science and Technology
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• v.30 no.4
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• pp.213-219
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• 2017

Polyalkylsiloxane has been spotlighted in pressure-sensitive adhesive (PSA) application due to excellent physical properties and good biocompatibility. Thermal behaviour of polyalkylsiloxane mixtures, such as thermal stability and heat flow, were studied using TG-DTA during catalytic hydrosilation. To understand reaction kinetics of cross-linking, catalytic hydrosilation of polyalkylsiloxane was monitored using variable temperature nuclear magnetic resonance (VT-NMR) as increased temperature. The formation of cross-linking bond $Si-CH_2-CH_2-Si$ was directly observed using distortionless enhanced by polarization transfer (DEPT) technique. Successfully polyalkylsiloxane PSA samples exhibited excellent adhesion properties by cross-linking reaction.

• Journal of Microbiology and Biotechnology
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• v.28 no.2
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• pp.262-266
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• 2018

Phytochemicals have been considered as alternatives for synthetic fungicides because of their biodegradability and low toxicity. In this study, we found that the methanolic extract of Corydalis ternata suppressed the development of plant diseases caused by Puccinia triticina and Colletotrichum coccodes. As the antifungal substance, three isoquinoline alkaloids (dehydrocorydaline, stylopine, and corydaline) were isolated from C. ternata. These active compounds also exhibited in vivo antifungal activity against P. triticina and C. coccodes. Taken together, our results suggest that C. ternata and its active compounds can be used to control plant diseases.

• Bulletin of the Korean Chemical Society
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• v.26 no.10
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• pp.1512-1514
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• 2005

Catalytic properties of Ni-Zr$O_2$ catalysts prepared by coprecipitation have been studied for the gas-phase hydrogenation of 1,3-butadiene to butenes. The coprecipitation method led to the solid solution of Ni-Zr$O_2$, which contains highly resistant Ni species to thermal reduction with H2. Nickel species of the solid solution were highly dispersed in the ZrO2 lattice, so that the reduced catalysts were selective for hydrogenation of 1,3-butadiene to butenes (99.9%) even in the presence of 1-butene.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2005.09a
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• pp.40-44
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• 2005

Catalytic performance of Co catalysts supported on MgO for the formation of multiwall carbon nanotubes (MWCNTs) Having 40-60 nm in diameter has been investigated through acetylene decomposition at $600^{\circ}C$. Scanning electron microscopy measurements show that the nanotubes are chain and coiled structures whereas x-ray diffraction patterns indicate the formation of MWCNTs with Co nanoparticles. In addition Raman spectra confirms the format ion of MWCNTs due to presence of characteristic radial breathing mode along with D and G bands.

• Journal of Electrochemical Science and Technology
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• v.2 no.3
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• pp.174-179
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• 2011

The mesoscopic $Sb_2S_3$-sensitized photoelectrochemical solar cells using cobalt redox electrolyte exhibit nonlinear behavior of power conversion efficiency with illuminated sun intensity. From the measurement of bulk diffusion and electrochemical impedance spectroscopy studies, we suggest that the nonlinearity of device performance with illuminated sun intensity is attributed not to the slow bulk diffusion problem of cobalt electrolyte but to the limited mass transport in narrowed pore volume in mesoscopic $TiO_2$ electrode.

• Membrane Journal
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• v.28 no.3
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• pp.187-195
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• 2018

In this work, the morphology of polyvinylidene-co-hexafluoropropylene (PVDF-co-HFP) membranes were systemically investigated using phase inversion technique, to target membrane contactor applications. As the presence of macrovoids degrade the mechanical integrity of the membranes and jeopardize the long-term stability of membrane contactor processes (e.g. wetting), a wide range of dope compositions and casting conditions was studied to eliminate the undesired macrovoids. The type of solvent had significant effect on the membrane morphology, and the observed morphology were correlated to the physical properties of the solvent and solvent-polymer interactions. In addition, to fabricate macrovoid-free structure, the effects of different coagulation temperatures, inclusion of additives, and addition of nonsolvents were investigated. Due to the slow crystallization rate of P(VDF-co-HFP) polymer, it was found that obtaining porous membrane without macrovoids is difficult using only nonsolvent-induced phase separation method (NIPS). However, combined other phase inversion methods such as evaporation-induced phase separation (EIPS) and vapor-induced phase separation (VIPS), the desired membrane morphology can be obtained without any macrovoids.

• Applied Chemistry for Engineering
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• v.32 no.5
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• pp.569-573
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• 2021

In this study, high-density carbon blocks were manufactured using coke, binder pitch, and impregnated pitch, then the effect of pitch fluidity on the densification of carbon blocks during the impregnation process was investigated. A green block was manufactured through high-pressure figuration of coke and binder pitch, and a carbon block was obtained through a heat treatment process. An impregnation process was performed to remove pores generated by volatilization of the binder pitch during the heat treatment process. The impregnation process was carried out the high-pressure reaction step of impregnating the pitch into the carbon block followed by the pretreatment step of melting the impregnation pitch. Melting of the impregnation pitch was carried out at 140~200 ℃, and the viscosity of the impregnation pitch decreased as the heat treatment temperature increased. The decrease in the viscosity of the impregnation pitch improved the fluidity and effectively impregnated the pores inside the carbon block, reducing the porosity of the carbon block by 83% and increasing the apparent density by 5%.

• Toxicological Research
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• v.21 no.3
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• pp.209-218
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• 2005

We investigated effects of recombinant human erythropoietin (rHuEPO) on profiles of mRNA transcripts in 6 male cynomolgus (M. fascicularis) monkey's spleen for 4 weeks. Six monkeys, composed of control and treatment group (Control : M1, M2, M3: Treatment : M4, M5, M6) were intravenously administered 3 times per week without or with a dose of rHuEPO 2730 IU/0.1 ml/kg. After 4 weeks rHuEPO treatment, spleen was removed for RNA isolation. Splenic gene expression was assessed using Affymetrix U133A 2.0 arrays containing 18,400 transcripts and variants, including 14,500 well-characterized human genes. Gene expression pattern was very different between individuals even in same treatment. In rHuEPO treated groups showed number of genes were up- or down-regulated (M4: 79: M5: 48; M6: 73 genes). Six genes (epidermal growth factor receptor, calgranulin A, estrogen receptor binding site associated antigen, matrix metalloproteinase 19, zinc finger and BTB domain containing 16, progestin and adipoQ receptor) were commonly expressed in rHuEPO treated group. The different individual response could be major considering factor in monkey experiment. Further study is needed to clarify the different individual response to rHuEPO in molecular level. This study will be valuable in the fundamental understanding and validation of molecular toxicology for bio-generic drugs including rHuEPO in cynomolgus monkey.

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.08a
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• pp.151.4-151
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• 1998