• Journal of the Korean GEO-environmental Society
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• v.20 no.11
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• pp.5-10
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• 2019

For the development of long-wavelength responding photocatalyst, Ag was applied to commercial $TiO_2$ to produce $Ag/TiO_2$ photocatalyst. Moreover, micro-emulsion method was used in order to increase the efficiency of the photocatalyst by enhancing the dispersion of Ag. Physical properties of the manufactured catalyst were analyzed by scanning electron microscopy (SEM), field emission transmission electron microscopy (FE-TEM) and diffuse reflectance spectroscopy (DRS). For the catalytic performance measurement, RO 16 (Reactive Orange 16) removal was performed with 25 ppm RO 16 under UV-A (365 nm) irradiation. In addition, ball milling and dip-coating method were used to synthesize the photocatalyst for the comparison of the outcomes of using different synthesis methods. In addition, catalytic performance was improved by varying the Ag content and surfactant content. The highest catalytic performance was shown at $Ag/TiO_2$ synthesized by micro-emulsion method with 2 wt% of Ag content, and 0.5 g of the surfactant.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.667-674
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• 2020

The adsorption of reactive orange 16 (RO 16) dye by activated carbon was investigated using the amount of adsorbent, pH, initial concentration, contact time and temperature as adsorption variables. The investigated process parameters were separation coefficient, rate constant, rate controlling step, activation energy, enthalpy, entropy, and free energy. The adsorption of RO 16 was the highest at pH 3 due to the electrostatic attraction between the cations (H⁺) on the surface of the activated carbon and the sulfonate ions and hydroxy ions possessed by RO 16. Isotherm data were fitted into Langmuir, Freundlich and Temkin isotherm models by applying the evaluated separation factor of Langmuir (RL=0.459~0.491) and Freundlich (1/n=0.398~0.441). Therefore, the adsorption operation of RO 16 by activated carbon was confirmed as an appropriate removal method. Temkin's adsorption energy indicated that this adsorption process was physical adsorption. The adsorption kinetics studies showed that the adsorption of RO 16 follows the pseudo-second-order kinetic model and that the rate controlling step in the adsorption process was the intraparticle diffusion step. The positive enthalpy change indicated an endothermic process. The negative Gibbs free energy change decreased in the order of -3.16 <-11.60 <-14.01 kJ/mol as the temperature increased. Therefore, it was shown that the spontaneity of the adsorption process of RO 16 increases with increasing temperature.

• Journal of Life Science
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• v.18 no.10
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• pp.1331-1335
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• 2008

A Klebsiella pneumoniae WL-5 with the capability of decolorizing several recalcitrant dyes was isolated from activated sludge of an effluent treatment plant of a textile and dyeing industry. This strain showed a higher dye decolorization under static condition and color removal was optimal at pH 6-8 and $30-35^{\circ}C$. More than 90% of its color of Congo Red were reduced within 12 hr at $200\;{\mu}M$ dye concentration. Malachite Green, Brilliant Green and Reactive Black-5 lost over 85% of their colors at $10\;{\mu}M$ dye concentration, but the percentage decolorization of Reactive Red-120, Reactive Orange-16, and Crystal Violet were about 46%, 25%, and 13%, respectively. Decolorizations of Congo Red and triphenylmethane dyes, such as Malachite Green, Brilliant Green, and Crystal Violet were mainly due to adsorption to cells, whereas azo dyes, such as Reactive Black-5, Reactive Red-120, and Reactive Orange-16 seemed to be removed by biodegradation through unknown enzymatic processes.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.12a
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• pp.95-102
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• 2005

For decolorization of synthetic dyes, Isolate fungi were investigated for the decolorization of 8 industrial dyes. One fungus isolated from textile wastewater collected from Banweol industrial complex, Korea showed excellent ability for removing synthetic dyes. Internal Transcribed Spacers (ITS) sequencing result was confirmed as the new Basidomycetes species. HUE05-1 The optimal decolorizaton conditions were pH5, 30$^{\circ}C$ and aerobic condition. HUE05-1 was completely decolorized all dyes in both solid and liquid condition. The result is decolorization effect at Reactive Orange 16; 97.12%, Reactive Blue 19; 92.09%, Reactive Blue 49; 97.04%, Reactive Yellow 145; 95.53%, Acid Orange 10; 99.18%, Acid Violet 43; 98.73%, Acid Blue 350; 94.71%, Disperse Blue 106; 90.07%.

• Journal of Environmental Health Sciences
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• v.32 no.4 s.91
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• pp.381-385
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• 2006

For decolorization of synthetic dyes, One fungus(HUE05-1) which was isolated from textile wastewater collected from industrial complex in Korea showed excellent ability of removing synthetic dyes. This fungus was identified as Basidiomycetes species by Internal Transcribed Spacers (ITS) sequence. Isolated fungi. HUE05-1 completely decolorized all dyes in both solid and liquid condition. The decolorization results were Reactive Orange-16, 97.12%; Reactive Blue-19, 92.09%; Reactive Blue-49, 97.04%; Reactive Yellow-145, 95.53%; Acid Orange-10, 99.18%; Acid Violet-43, 98.73%; Acid Blue-350, 94.71% and Disperse Blue-106, 90.07%.

• KSBB Journal
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• v.18 no.5
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• pp.398-403
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• 2003

Due to the low biodegradability of dyes, conventional biological wastewater treatment systems are inefficient in treating dye wastewater. Various white-rot fungi were investigated for the decolorization of six industrial dyes (reactive blue 5, reactive blue 16, reactive black 5, acid black 52, reactive orange 16, and acid violet 43). Among ten fungi, T. versicolor KCTC 16781 was selected as a testing strain because this had the best performance of decolorization for six dyes from the results of the solid culture experiments. In liquid culture medium, T. versicolor KCTC 16781 decolorized over 96% of six dyes for 48 hrs. Laccase started to produce in the early stage of the culture, and showed the highest peak value of 2.3 U/mL in 24 hrs. Enzyme activity remained constant until the end of culture. Fungal decolorization is a promising alternative to replace or supplement present treatment process.

• Korean Chemical Engineering Research
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• v.57 no.2
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• pp.232-238
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• 2019

Polyethylenimine-crosslinked chitin (PEI-chitin) was developed as a biosorbent to effectively remove dyestuffs from dye-containing wastewater. A representative reactive dye, Reactive Orange 16 (RO16) was used as a model dye. The effect of pH, isotherm, kinetic and desorption experiments were performed to evaluate the adsorption/desorption ability of PEI-chitin for RO16. As a result, the maximum adsorption capacity calculated by the Langmuir model was 266.3 mg/g at pH 2, and the time needed for adsorption equilibrium was evaluated to be about 20, 60, and 240 min for 50, 100, and 200 mg/L, respectively. The desorption experiments were carried out using various eluents such as ammonia/ethanol mixture, NaOH, $NaHCO_3$, and $Na_2CO_3$, and the highest desorption rate was 75.24% in the ammonia/ethanol mixture.

• Textile Coloration and Finishing
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• v.6 no.4
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• pp.9-16
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• 1994

알칼리 수용액 중에서의 Vinylsulfone(VS)계 반응성염료의 혼합상태의 가수분해 반응을 정량적으로 조사하였다. 혼합이량체의 생성 및 분해반응 속도상수를 각각의 염료의 가수분해반응에서 구한 속도상수를 이용하여 계산하였다. 단독이량체를 생성하는 염료들을 조합하였을 경우에는 혼합이량체가 생성되었다. C.I.Reactive Blue 19가 다른 VS계 염료들과 혼합되었을 경우에는 일반적으로 혼합이량체가 생성되었다. Blue 19와 Orange 16의 조합의 경우에는 낮은 염료농도에서만 혼합이량체가 생성되었으며, Red 22의 경우에는 단독 및 혼합이량체가 생성되지 않았다. 단독이량체가 생성되지않는 Orange 7는 다른 VS계 염료들과의 조합에서 혼합이량체를 생성함을 확인하였다. Yellow 17의 혼합이량체의 분해속도 상수값이 가장 큼을 알 수 있었다.

• Journal of Food Hygiene and Safety
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• v.39 no.3
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• pp.273-280
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• 2024

In this study, the antibacterial activity and mechanisms of bitter orange extract, a natural antibacterial agent, were investigated, with a focus on its potential application in washing water for controlling Salmonella Typhimurium contamination of salad, a ready-to-eat food. The minimum inhibitory concentration (MIC) of bitter orange extract against S. Typhimurium was determined using the broth dilution method. Subsequently, S. Typhimurium was exposed to various concentrations of bitter orange extract (1/16 MIC-2 MIC) and growth curves were measured. Following treatment with bitter orange extract, we investigated its antibacterial mechanism by measuring intracellular reactive oxygen species (ROS) levels, alterations in membrane potential and integrity, and nucleic acid leakage in S. Typhimurium. Additionally, salads artificially contaminated with S. Typhimurium were treated with different concentrations of bitter orange extract using the dipping method for various durations to assess the reduction effect. The MIC of bitter orange extract against S. Typhimurium was 195.313 mg/L, and bacterial growth was completely inhibited at a concentration of 1 MIC. Furthermore, an increase in bitter orange extract concentration correlated with elevated intracellular ROS levels, membrane potential disruption, membrane damage, and nucleic acid release. Importantly, salads treated with bitter orange extract exhibited a significant reduction in S. Typhimurium counts compared to the control, and prolonged treatment times resulted in further reductions in bacterial counts. Bitter orange extract was more effective than sodium hypochlorite and can be used as a safer salad wash. These findings indicate the potential treatment of salads to prevent foodborne illnesses.

• Textile Coloration and Finishing
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• v.8 no.1
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• pp.1-7
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• 1996

In discharge printing of cotton fabrics dyed with C.I. Reactive Orange 16(O-16), C.I. Reactive Blue 19(B-19) and C.I. Reactive Black 5(Bl-5), when the dyes were discharged by some chemicals, such as $K_{2}CO_{3}$, BASB, DSR, sarcosine and GSB, the single use of those chemicals made a very poor discharge, but mixing them with $K_{2}CO_{3}$ resulted to the outstanding improvement of discharge. Especially the dischargeability of $K_{2}CO_{3}$ BASB or $K_{2}CO_{3}$+DSR was very gratifying. For O―16, $K_{2}CO_{3}$+ DSR was slightly more effective than $K_{2}$CO$_{3}$+BASB, but for B―19 and Bl―5 $K_{2}CO_{3}$+BASB and $K_{2}CO_{3}$+DSR showed similar good results. In discharging of O―16 and B―19 by $K_{2}CO_{3}$+BASB or $K_{2}CO_{3}$ +DSR, the dischargeabilities of them increased as the time of 102$^{\circ}C$ steaming increased under the condition of 102$^{\circ}C$ steaming and no baking, but not under the condition of 102$^{\circ}C$ steaming and 16$0^{\circ}C$ baking. However for Bl-5, without regard to baking, the 102$^{\circ}C$ steaming of more than 15 minutes caused the discharge to be much more remarkable than that of 8 minutes did. Generally baking elevated the dischargeability, and this was sure in discharging by $K_{2}CO_{3}$+BASB or $K_{2}CO_{3}$+DSR. And it was confirmed that the structure of vinylsulfonyl reactive dyes could effect on the dischargeability because the three dyes, though little, showed different discharge behaviors.