• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.652-655
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• 2009

The bimodal porous carbons were synthesized by using imprinting method with templates of SBA-15 particle and silica sphere and applied as supporting materials for the electro-catalyst of polymer electrolyte fuel cell (PEFC). The silica spheres with diameter size of 100 nm and SBA-15 particle having 200 nm -250 nm diameter and 700 nm -900 nm length were synthesized in this work. The bimodal porous carbons (S100) were prepared by using the silica spheres and SBA-15 as templates and mesophase pitch as a carbon source. The PtRu nanoparticle of ca. 1.9 nm were supported on the bimodal porous carbon support and the resulting PtRu/S100 catalysts was tested by the cyclic voltammetry. The use of bimodal porous carbon showed in comparable electro-catalytic activities with commercial catalyst. Though unclear effects of bimodal porosity of supports could be obtained in the scope of this study, morphological advantage in electrical conductivity can be considered on the electro-catalytic activity.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2618-2626
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• 2010

In this paper poly (4-methyl vinylpyridinium hydroxide)/SBA-15 composite was prepared as a highly efficient heterogeneous basic catalyst by in situ polymerization method for the first time. It was characterized by XRD, FT-IR, BET, TGA, SEM and back titration using NaOH. This catalyst exhibited the excellent catalytic activities for the Knoevenagel condensation of various aldehydes with ethyl cyanoacetate. Over this catalyst, ${\alpha},{\beta}$-unsaturated carbonyl compounds were obtained in the reasonable yield at $95^{\circ}C$ in 10 - 30 min in $H_2O$ as a solvent with a 100% selectivity to the condensation products. Catalyst could be easily recycled after the reaction and it could be reused without the significant loss of activity/selectivity performance. No by-product formation, high yields, short reaction times, mild reaction conditions and operational simplicity with reusability of the catalyst were the salient features of the present synthetic protocol. Presence of $H_2O$ as a solvent was also recognized as a "green method".

• Macromolecular Research
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• v.17 no.9
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• pp.638-645
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• 2009

We report the effect of the amount of the mesoporous material, SBA-15, on the basic traits of fully aliphatic polyimides (API). For this purpose, water soluble, fully aliphatic poly(amic acid) triethyl amine salts ($PAA_{(s)}$) were prepared and mixed with various amounts of SBA-15. Fully aliphatic polyimide hybrid composites containing the SBA 15-type mesoporous silica were synthesized successfully from bicyclo [2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride and alicyclic diamine, 4,4'-methylene bis(2-methylcyclohexylamine). The structure of the hybrid composites was confirmed by IR spectroscopic analysis. Scanning electron microscopy revealed the morphology of the compounds. The hybrid composites exhibited good thermal stability, reasonable transparency, and a low dielectric constant.

• Resources Recycling
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• v.22 no.4
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• pp.38-45
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• 2013

The porous ceramic beads using mine tailing were prepared and applied to catalytic converter for NOx/SOx removal. Catalytic support was used synthesized mesoporous silica (SBA-15) which coated on surface. Internal structure for porous ceramic beads was composed of three-dimensional network structure and porosity was about 80%. In addition, the specific surface area for mesoporous silica(SBA-15) coated on converter was significantly increased 55 $m^2/g$ compared with 0.8 $m^2/g$ before coating. NOx/SOx removal experiment was performed using $V_2O_5$ and $V_2O_5$/CuO converter. NOx conversion ratio for $V_2O_5$/CuO converter was approximately increased 10% compared to $V_2O_5$ converter. In addition, catalytic converter of $V_2O_5$/CuO was shown to remove 95% of NOx and 90% of SOx at reaction temperature of $350^{\circ}C$, space velocity of 10000 $h^{-1}$ and $O_2$ concentrations of 5%, respectively.

• Korea Information Processing Society Review
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• v.15 no.6
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• pp.5-13
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• 2008

• Korea Information Processing Society Review
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• v.15 no.6
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• pp.41-51
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• 2008

• Applied Chemistry for Engineering
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• v.26 no.1
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• pp.80-85
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• 2015

Silicon/carbon composites as anode materials for lithium-ion batteries were examined to find the cycle performance and capacity. Silicon/carbon composites were prepared by a two-step method, including the magnesiothermic reduction of SBA-15 (Santa Barbara Amorphous material No. 15) and carbonization of phenol resin. The electrochemical behaviors of lithium ion batteries were characterized by charge/discharge, cycle, cyclic voltammetry and impedance tests. The improved electrochemical performance attributed to the fact that silicon/carbon composites suppress the volume expansion of the silicon particles and enhance the conductivity of silicon/carbon composites (30 ohm) compared to that of using the pure silicon (235 ohm). The anode electrode of silicon/carbon composites showed the high capacity approaching 1,348 mAh/g and the capacity retention ratio of 76% after 50 cycles.

• Journal of the Korea Organic Resources Recycling Association
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• v.15 no.3
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• pp.71-79
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• 2007

The effects of synthetic bulking agent (SBA) on the composting reaction were investigated with a lab-scale composting reactor. The positive effects of SBA addition were observed in composting reactions where relatively tough composting conditions like high water content and no addition of seed compost were provided. Such effects were assumed to be caused by the enhanced free air space in compost mixture. It was additional benefits of using SBA, a bulking agent, that the amount of saw dust, another bulking agent, could be reduced to 50% compared to composting without SBA. Although SBA would be used as a bulking agent, two options are thought to be very important to ensure composting reaction well. One is that optimal water content should be maintained around 60%. The other is that saw dust is inevitable bulking agent to prevent food waste from lumping, so combination use of two ones are necessary.

• Applied Chemistry for Engineering
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• v.31 no.4
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• pp.383-389
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• 2020

Mesoporous silica solid catalysts modified with sulfonic acid were prepared for cationic ring-opening polymerization of octamethylcyclotetrasiloxane (D₄). Two sets of MCM-41 (1.7 and 2.8 nm) and SBA-15 (8.1 and 15.9 nm) with different pore sizes were used as catalyst supports. The surface of silica materials was modified with (3-mercaptopropyl)trimethoxysilane by silylation reaction and oxidized to sulfonic acid. The structures of the prepared catalysts were examined by X-ray diffraction and nitrogen adsorption-desorption. The pore size, specific surface area, and pore volume of the modified solid catalysts decreased slightly. In addition, the modification of the sulfonic acid on the silica surface was confirmed by using infrared spectroscopy and nuclear magnetic resonance spectroscopy. To observe the effect of the particle size on the catalytic activity, it was observed with a scanning electron microscope. The catalysts were used to synthesize PDMS through a ring-opening polymerization of D₄, and the conversion and polymerization rate of the polymerization reaction depended on the pore size, specific surface area, particle size, and particle agglomeration of the catalysts. In order for the polymerization rate, the catalyst prepared with SBA-15 of 8.1 nm pore size had the fastest reaction rate and showed the best catalytic activity.

• Applied Chemistry for Engineering
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• v.16 no.1
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• pp.1-8
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• 2005

Electrorheological (ER) fluids, typically composed of particles having higher dielectric constant or electric conductivity than that of suspending fluids with a low viscosity, undergo dramatic, reversible changes when exposed to an external electric field. Among various electroactive materials, we put our efforts on inorganic materials including zeolite, MCM-41, MCM-41/polyaniline composite and SBA-15/polyaniline composites. Their preparation and ER characteristics are introduced.