• Journal of Korean Society of Water and Wastewater
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• v.25 no.5
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• pp.643-649
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• 2011

Degradation of benzothiophene(BT) in the aqueous phase by potassium ferrate(VI) was investigated. Potassium ferrate(VI) was prepared by the wet oxidation method. The degradation efficiency of BT was measured at various values of pH, ferrate(VI) dosage and initial concentration of BT. BT was degraded rapidly within 30 seconds by ferrate(VI). While the highest degradation efficiency was achieved at pH 5, the lowest degradation efficiency was achieved at pH 9. Also, the initial rate constant of BT increased with decreasing of the BT initial concentration. In addition, the intermediate analysis for the reaction of BT and ferrate(VI) has been conducted using GC-MS. Benzene, styrene, benzaldehyde, formaldehyde, benzoic acid, formic acid, and acetic acid were identified as reaction intermediates, and ${SO_4}^{2-}$ was identified as an end product.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.129-129
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• 2010

The conjugated oligomers with rigid and fused-ring structures are of interest for the solution-processable organic thin film transistors (OTFTs) due to their well defined structure and high purity. In this study, alkyl substituted benzothiophene based oligomers were synthesized by a novel route, the key point of which is the acid-induced intermolecular cyclization reaction of aromatic methyl sulfoxides, and were confirmed by $^1H$-NMR and FT-IR studies. The obtained oligomers showed the good solubility in common organic solvents such as hexane, chloroform, and dimethylchloride at room-temperature, which is due to the introduced alkyl chain. The physical and optical properties of the oligomers were studied using differential scanning scalorimetry (DSC), cyclic-voltammetry (CV), UV-visible and PL spectra studies. Solution processed OTFT device based on synthesized oligomers show a high hole mobility of up to $0.01\;cm^2V^{-1}s^{-1}$, $I_{on}/I_{off}$ of $10^5$ and threshold voltage of -14V.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.4
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• pp.527-534
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• 2011

In this research, the photocatalytic degradation of dibenzothiophene (DBT) in $TiO_2$ aqueous suspension has been studied. $TiO_2$ photocatalysts are prepared by a sol-gel method. The dominant anatase-structure on $TiO_2$ particles is observed after calcining the $TiO_2$ gel at $500^{\circ}C$ for 1hr. Photocatalysts with various transition metals (Nd, Pd and Pt) loading are tested to evaluate the effect of transition metal impurities on photodegradation. The photodegradation efficiencies with $TiO_2$ including Pt and Pd are higher than pure $TiO_2$ powder. Also we investigated the applicability of $H_2O_2$ to increase the efficiency of the $TiO_2$ photocatalytic degradation of dibenzothiophene. The degradation efficiency increases with increasing dosage of $H_2O_2$ in the range of 0.01M to 0.1M . The effect of pH is investigated; we obtained the maximum photodegradation efficiency at pH 5. In addition, the intermediate analysis found dihydroxyl -dibenzothiophene as a reaction intermediate of dibenzothiophene during the photodegradation.