• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.479-482
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• 2003

In this study, the solubilization of dense nonaqueous phase liquid (DNAPL) using oil-based emulsion was investigated for aquifer remediation. The micro-sized oil emulsion has large surface areas and buoyancy force, therefore it can be effective in treating DNAPL pool of the aquifer without downward migration of DNAPLs. The emulsion was prepared using silicone oil and mechanical homogenization. And the prepared emulsion had micro-sized similar distribution: 99 % in number and 80 % in volume were less than 10${\mu}{\textrm}{m}$. As target pollutants, trichloroethylene and 1, 2 dichlorobenzene were selected. All of used DNAPLs were solubilized successfully in oil-based emulsion. Even at low oil percentage, emulsion showed good solubility against pollutants. Therefore, the remediation using oil-based emulsion was considered as an effective alternative in dealing with DNAPLs of the aquifer.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.3
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• pp.265-265
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• 1998

The phase behavior of chlorinated hydrocarbon/mixed surfactants/water microemulsion systems were investigated for dry cleaning solvent properties. With appropriate surfactant mixtures, Winsor type I-III-II microemulsions were generated which is the same as hydrocarbon systems. For perchloroethylene(PCE) with mixed Tween systems, the optimum salinity(S*) decreases and the optimum solubilization parameter(o*) increases with decreas- ing HLB. For PCE with mixed Aerosol MA and ethoxylated alcohol systems, S* and o* both increase with increasing ethylene oxide moles. For dichlorobenzene(DCB) with mixed Aerosol MA and ethoxylated or propoxylated sulfate systems, S* and o* both increase with increasing ethylene oxide moles or propylene oxide moles.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.3
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• pp.365-373
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• 1998

The phase behavior of chlorinated hydrocarbon/mixed surfactants/water microemulsion systems were investigated for dry cleaning solvent properties. With appropriate surfactant mixtures, Winsor type I-III-II microemulsions were generated which is the same as hydrocarbon systems. For perchloroethylene(PCE) with mixed Tween systems, the optimum salinity(S*) decreases and the optimum solubilization parameter(o*) increases with decreas- ing HLB. For PCE with mixed Aerosol MA and ethoxylated alcohol systems, S* and o* both increase with increasing ethylene oxide moles. For dichlorobenzene(DCB) with mixed Aerosol MA and ethoxylated or propoxylated sulfate systems, S* and o* both increase with increasing ethylene oxide moles or propylene oxide moles.

• Bulletin of the Korean Chemical Society
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• v.24 no.9
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• pp.1329-1332
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• 2003

Stepwise dechlorination of 1,2,4-trichlorobenzene was observed at a glassy carbon electrode in dimethylformamide containing 0.1 M tetraethylammonium perchlorate. Especially, dechlorination to dichlorobenzene and further to monochlorobenzene or benzene was successfully demonstrated with a porous reticulated vitreous carbon electrode. Electrochemical dechlorination of polychlorobenzenes employing a flow cell with a reticulated vitreous carbon working electrode is also described. Preliminary experiments with a flow cell showed that dechlorination of trichlorobenzene to dichlorobenzene was partially completed while dechlorination to benzene or monochlorobenzene was not successful, suggesting that a flow rate and electrolysis time should be further optimized for the complete electrolysis.

• Bulletin of the Korean Chemical Society
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• v.16 no.6
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• pp.507-511
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• 1995

Catalytic chlorination of chlorobenzene was studied in vapor phase using various solid-acid catalysts such as silica-alumina, alumina, zeolite and a modified clay prepared by impregnating bentonite with ferric chloride. The conversions of both chlorine gas and chlorobenzene showed high over silica-alumina, alumina and modified clay catalysts. However relatively large amounts of polychlorinated benzene derivatives were also observed. The active species of catalytic activity in chlorination of chlorobenzene in vapor phase were proved to be as Lewis acid sites by in-situ IR experiments. The strength of Lewis acid sites which were effective for the vapor-phase chlorination seemed to be having Hammett acidity Ho >-3.0. The selectivity to dichlorobenzenes was proved to be high over the zeolite catalyst due to their shape-selective properties. p-Dichlorobenzene or dichlorobenzene selectivities were improved more or less by changing the reaction conditions.

• Elastomers and Composites
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• v.49 no.2
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• pp.155-159
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• 2014

High resolution ultrasonic spectroscopy was used to observe the oxidation of [$C_{70}$]fullerene with 3-chloroperoxy benzoic acid in 1,2-dichlorobenzene. UV-vis spectroscopy and X-ray diffraction confirmed the resulting roducts of [$C_{70}$]fullerene oxidation.

• Applied Chemistry for Engineering
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• v.20 no.5
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• pp.522-526
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• 2009

The catalytic oxidation of 1,2-dichloribenzene (1,2-DCB) and simultaneous catalytic reduction of nitrogen oxides over the single catalyst has been investigated over various metals (Ru, Mn, Co and Fe) supported on $Al_2O_3$ and $CeO_{2}$. The activity of the different catalysts for catalytic oxidation of 1,2-dichloribenzene depended on the used metal, Ru/Co/$Al_2O_3$, Mn-Fe/CeO2 and Cr/$Al_2O_3$ (commercial catalysts) being the most actives ones. In the catalytic oxidation of chlorobenzene (CB), Ru/Co/$Al_2O_3$ is better than Pt-Pd/$Al_2O_3$, which is the well-known catalyst good for VOC oxidation. Furthermore, it has a good durability on the deactivation by $Cl_2$ and sulfur. For nitrogen oxides (NOx) removal, NOx conversion was 70% at $260^{\circ}C$.

• 산업보건소식
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• no.45
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• pp.46-48
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• 1987

산업이 다양화.고도화됨에 따라 생산공정중에 불가피하게 발생되는 수많은 유해물질의 포집, 분석 방법에 대하여 우리실정에 알맞는 표준방법을 정함으로써 사업장 유해환경측정에 참고가 되고 나아가서 작업환경측정방법의 일원화를 도모하고자 노동부 국립노동과학연구소에서 수년간에 걸쳐 비교 연구하여 최근 보고한 바 있는 유해물질의 표준 실험 방법을 소개하고자 한다.

• Korean Chemical Engineering Research
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• v.47 no.6
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• pp.747-754
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• 2009

In this study, adsorption isotherms of o-DCB(ortho-dichlorobenzene) on an activated carbon heated at $1000^{\circ}C$ for 24 hours were obtained by experiment and were predicted by using molecular simulation. The initial molecular structure of the activated carbon was designed on the basis of its molecular formula and functional groups ratio measured experimentally. Then, the molecular structure was optimized using the COMPASS(condensed-phase optimized molecular potentials for atomistic simulation studies) force field. The particle porosity, specific surface area, and particle density obtained from the optimized molecular structure of activated carbon were compared with those experimental data. The errors between experimental data and simulation results of the particle porosity, specific surface area, and particle density were shown as 7.6, 3.8, and 2.8%, respectively. Adsorption isotherms constants of o-DCB are calculated by the GCMC(grand canonical Monte Carlo) method in the optimized molecular structure of activated carbon. The simulation result of the adsorption isotherms showed an error of under 3%, compared to that of experimental data. Adsorption isotherms, adsorption heat and pore diffusivity of 2,3,7,8-TCDD(tetrachlorodibenzo-p-dioxin) was finally obtained in the same molecular structure of the activated carbon as used for o-DCB. Thus, adsorption characteristics of persistent organic pollutants on activated carbon, which are not easy to experimentally evaluate, are predicted by the molecular simulation.

• Journal of Aquaculture
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• v.21 no.1
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• pp.7-12
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• 2008

Toxicity of ten commercial disinfectants(hydrogen peroxide, sodium hypochlorite, chlorine dioxide, povidon iodine, formaldehyde, glutaraldehyde, quaternary ammonium compounds(QAC), didecyl dimethyl ammonium chloride(DDAC), ortho-dichlorobenzene, and copper sulfate) was measured by chinook salmon embryo-214 cell line and three fish species: flounder Paralichthys olivaceus, black rockfish Sebastes pachycephalus, and black sea bream Acanthopagrus schlegelii. The $LC_{50}$ levels of 24 hours acute toxicity with the ten disinfectants were tested in three species of fish. Effectiveness of ten chemical disinfectants were varied by each chemical as well as by species. Hydrogen peroxide showed the higest activity at 201, 269, and 139 ppm in the flounder, the black rockfish, and black sea bream, respectively. DDAC showed the lowest activity at 2.1, 1.0, and 1.5 ppm in the flounder, the black rockfish, and black sea bream, respectively. The highest variation was observed in copper sulfate by both the chemicals and the species.