• Journal of Korean Society of Water and Wastewater
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• v.20 no.1
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• pp.79-85
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• 2006

Innovated technique to oxidize pollutants has been developed. The technique for this study uses plasma discharge in 2-phase (Air-Water) and is called Discharged Water Generating (DWG) system. It produces electric arc which generates not only the physical decomposing power against the pollutants but also oxidants to sterilize pollutants depending on the inlet gas species. These physical and chemical products play an important role in COD decrease and biodegradability enhancement. The enhancement of biodegradability for the refractory organic substances in aqueous solution was estimated in this study. Argon discharge reduced NBDCOD of EDTA from 58.7mg/L to 38.8mg/L, but oxygen discharge and ozonation reduced it to 37.74mg/L and 38.73mg/L respectively. Furthermore, Argon discharge changed 1181mg/L of NBDCOD of dye effluent into 606mg/L but oxygen discharge and ozonation changed it into 888mg/L and 790mg/L respectively.

• Textile Coloration and Finishing
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• v.22 no.2
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• pp.94-100
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• 2010

Colored compounds adsorption from the textile dyeing effluents on activated carbons produced from various indigenous vegetable sources by zinc chloride activation is studied. The most important parameters in chemical activation were found to be the chemical ratio of $ZnCl_2$ to feed (3:1), carbonization temperature (460-470 $^{\circ}C$) and time of activation (75 min). The absorbance at 511 nm (red effluent) and 615 nm (blue effluent) are used for estimation of color. It is established that at optimum temperature ($50^{\circ}C$), time of contact (30-40 min) and adsorbent loading (2 g/L), activated carbons developed from rain tree (Samanea saman) saw dust and blackberry (Randia formosa) tree saw dust showed great capability to remove color materials from the effluents. It is observed that adsorption of reactive dyes by all types of activated carbons is more than that of disperse dyes. It is explained that because of its acidic nature the activated carbon can adsorb better reactive dye particles containing large number of nitrogen sites and $-SO_3Na$ group in their structure. The use of activated carbons from the indigenous biomass would be economical, because saw dusts are readily available waste worldwide.

• Korean Chemical Engineering Research
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• v.46 no.2
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• pp.310-315
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• 2008

Organic-inorganic hybrid solutions were made using glycidoxypropyl trimethoxysilane (GPTMS) and vinyltriethoxysilane (VTES) as starting materials by sol-gel method. Photochromic coating solutions were prepared by mixing the solution of photochromic dye (spiropyran) dissolved in ethylacetate with the organic-inorganic hybrid solutions. Photochromic films were prepared on polycarbonate sheets by spin coating and cured for 2 h at $100^{\circ}C$. The resulting films exhibited a reversible color change upon irradiation with UV light from transparent to blue. The color-fading speed and pencil hardness of the coating films increased with increasing the GPTMS content in the coating solutions.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.7
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• pp.641-646
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• 2005

To fabricate a single layer white organic light emitting diode (OLED), a novel non-conjugated blue emitting material PPPMA-co-DTPM copolymer was synthesized containing a perylene moiety unit with hole transporting and blue emitting ability and a triazine moiety unit with electron transporting ability. The devices were fabricated using PPPMA-co-DTPM $(PPPMA[70\;wt\%]:DTPM[30\;wt\%])$ copolymer by varying the doping concentrations of each red, green and blue fluorescent dye, by molecular-dispersing into Toluene solvent with spin coating method. In case of ITO/PPPMA-co-DTPM:TPB$(3\;mol\%):C6(0.04\;mol\%):NR(0.015\;mol\%)/Al$ structure, as they were molecular-dispersing into 30 mg/ml Toluene solvent, nearly-pure white light was obtained both (0.325, 0.339) in the CIE coordinates at 18 V and (0.335, 0.345) at 15 V. The turn-on voltage was 3 V, the light-emitting turn-on voltage was 4 V, and the maximum external quantum efficiency was $0.667\%$ at 24.5 V. Also, in case of using 40 mg/ml Toluene solvent, the CIE coordinate was (0.345, 0.342) at 20 V.

• Textile Coloration and Finishing
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• v.26 no.4
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• pp.283-289
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• 2014

This study describes the feasibility and optimization of reactive dyeing on bio treated cotton knitted fabrics. For this, cotton knitted fabrics distinctly with two different enzymes, alkaline Pectinases(Scourzyme $L^{(R)}$) and Pectate lyases(Bactosol Co. ip $liquor^{(R)}$). In this way by increasing the concentration and processing temperature, the access of enzymes towards the fatty and waxy substrate was found to be accelerated. To achieve higher absorbency and whiteness index, a series of experiments was carried out to assure that Pectate lyases enzymes possesses high access towards the fats and waxes at high temperature. To this end, cotton knitted fabrics was dyed without oxidative bleaching step. The Pectate lyases scoured and dyed fabrics showed less color difference when 2% dye shade is used. The fabrics pre-scoured with Pectate lyases showed good the light and washing fastness properties, compared to the conventional and Pectinases dyed fabrics. However pectinases enzymes showed lower activity at high temperature, caused poor wettability and whiteness index of fabrics. The improvement of the accessibility of enzyme to the pectin at higher temperature Pectate lyases treatment before dyeing was found to be useful for subsequent pectin degradation in cotton knitted fabrics.

• Korean Chemical Engineering Research
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• v.46 no.1
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• pp.112-117
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• 2008

Organic-inorganic hybrid solutions were prepared via sol-gel method using glycidoxypropyl trimethoxysilane (GPTMS) and methyl triethoxysilane (MTES) as starting precursors at a molar ratio of 1:1. The photochromic coating solutions were prepared by mixing the solutions of photochromic dye (spiropyran) dissolved in ethylacetate (EA) with the organic-inorganic hybrid solutions. Photochromic films were prepared on polycarbonate substrate by spin coating and cured for 2 h at $100^{\circ}C$. The resulting films exhibited a reversible color change upon irradiation with UV light. The photochromic properties of the films showed that the color-fading speed increases with increasing the EA content in the coating solutions.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.2
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• pp.217-222
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• 2004

The white-light-emitting organic LED(OLED) with two-wavelength was fabricated using the DPVBi of blue emitting material and a series of orange color fluorescent dye(Rubrene) by vacuum evaporation processes. The basic structure of white-light-emitting OLED was ITO/NPB(150$\AA$)/DPVBi/Rubrene/BCP(100$\AA$)/Alq$_3$(150$\AA$)/Al(600$\AA$). We analyzed the fabricated device through the changes of the DPVBi and Rubrene layer's thickness. We obtained the white-light-emitting OLED with white color light and the CIE coordinate of the device was (0.29, 0.33) at applied voltage of 13V when the thickness of DPVBi layer was 210$\AA$ and the thickness of Rubrene layer was 180$\AA$. At a current of 100㎃/$\textrm{cm}^2$, the quantum efficiency was 0.35％ and at a voltage of 20V, it was 0.405％.

• Analytical Science and Technology
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• v.10 no.3
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• pp.225-229
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• 1997

The stability of Rhodamine 6G Perchlorate(Rh6GP) doped in organically modified silicate(Ormosil) was investigated after the Ormosil was synthesized by sol-gel process. The composition of the Ormosil which makes organic dye molecules stable and dimer-free was decided from comparing absorption peaks of dye molecules in sol state, in wet gel and in completely dried gel. The stable and dimer-free Rh6GP doped in the Ormosil was achieved in the 0.1 molar ratio of HCl/TEOS.

• Journal of the Korean Chemical Society
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• v.39 no.3
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• pp.143-149
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• 1995

At low concentration a simplified model of organic dye-surfactant system has been used to evaluate. By applying the resultant three parameter equation to the experimental data, values for the equilibrium constants for the ion-pair formation $(K_O)$, surfactant molecule addition to aggregates $(K_S)$ and dye aggregation reactions $(K_D)$ could be calculated and changes of free energy have obtained from its values. $K_O$ and K_S$ values were larger than those expected electrostatic interaction indicatihng a hydrophobic contribution and the $K_D$ values were about 10~20 times higher than those found for association in pure aqueous solutions which can be ascribed to the screening effect of the electrostatic repulsion.

• Journal of Environmental Science International
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• v.13 no.6
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• pp.551-560
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• 2004

The feasibility and efficiency of the hydrogen peroxide produced by an electrolysis cell reactor was investigated, From regulating voltages for the given reaction time, the concentration of the hydrogen peroxide was gradually increased with increasing voltages. Optimal voltage range was found to be 10～15 V. The concentration of hydrogen peroxide was much higher with oxygen gas than without oxygen gas in the cathodic chamber. But there was a little difference in the generating rate of hydrogen peroxide regardless of the presence of nitrogen gas. Under given conditions, the maximum value of ICE(Instantaneous Current Efficiency) was about 38%, and then current density was 74 $mA/\textrm{cm}^2.$ The specific energy consumption was $0.694[kWh/kg-H_2O_2].$ Since Esp (Specific Energy Consumption)was very little value, It did not demand high energy in this system. Using the hydrogen peroxide gained in the experiment, Fenton's reaction was conducted and the removal of nitrobenzene, 3-chlorophenol and dye wastewater was studied. This results were very similar to the Fenton's reaction by using commercial hydrogen peroxide.