• Journal of the Korean Ceramic Society
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• v.52 no.6
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• pp.489-496
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• 2015

In this study, novel $Ag_2Se$ sensitized $TiO_2$ nanocomposites were prepared by facile sonochemical assisted synthesis method. The as-prepared products were characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis, transmission electron microscopy (TEM), and N2 adsorption BET analysis. The as-prepared $Ag_2Se/TiO_2$ nanocomposites simultaneously possessed great adsorptivity for organic dyes and efficient charge separation properties. In the decolorization of rhodamine B, a significant enhancement in the reaction rate was observed for the $Ag_2Se/TiO_2$ nanocomposite compared to the cases of using pure P25 or $TiO_2$. The sonocatalysis activity was higher due to the greater formation of reactive radicals, as well as to the increase of the active surface area of the $Ag_2Se/TiO_2$ nanocomposite.

• Journal of Ginseng Research
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• v.10 no.2
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• pp.193-199
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• 1986

To investigate the stability of ginseng saponin, various physical and chemical treatments for red ginseng alcohol extract (70% ethyl alcohol) were carried out, and then the variations of ginseng saponin in extract were investigated by high performance liquid chromatography (HPLC) method. Irradiation of ${\gamma}$-ray, and ultraviolet ray, sonocatalysis by ultrasonicator, treatment of electronic range, catalytic ozonation did not or slightly affect degradation of ginseng saponins, but they were degraded by heat treatment.

• Journal of Korean Society on Water Environment
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• v.28 no.2
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• pp.219-223
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• 2012

The fixed solid catalysts such as glass bead, steel mesh, and $TiO_2$ coated ceramic bead were used to investigate effect of radical production at different frequencies. The radical production rate at 300 kHz was faster than that at 35 kHz without solid, but the tendency was changed with the presence of glass bead. The presence of glass beads create non-continuous points between the solid and liquid phases leading to increased formation of cavitation bubbles. However, the radical production decreased when steel mesh was used at 35 kHz although the surface area of contact with liquid was same when glass bead was used. Hence the solid catalyst did not always enhance the radical production. The radical production using $TiO_2$ coated ceramic bead was dramatically increased at 35 kHz due to the breakage of $TiO_2$ coated ceramic bead. Therefore the radical productions at 300 kHz using fixed solid catalysts generally increased while at 35 kHz the results fluctuated according to the experimental conditions.