• Journal of Korean Society of Environmental Engineers
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• v.32 no.12
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• pp.1134-1140
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• 2010

Ozonation is a promising process that can effectively reduce the occurrence of micropollutants and pathogen in water. This study investigated the performance of ozonation for the removal of pharmaceuticals and personal care products (PPCPs) in secondary effluent from wastewater treatment plant. Moreover, the disinfection potential of ozonation applied for PPCPs removal was discussed. Secondary effluent filtered by sand filter was used for tested water, and ozonation was performed under 2, 4 and 6 mg/L of ozone doses. As a result, 6 mg/L of ozone dose (ozone consumption : 4.4 mg/L) was essential for the effective removal of 37 PPCPs in tested water. Several previous studies showed that the operation condition could achieve approximately 3 log inactivation of total coliform and enteroviruses. On the other hand, dissolved ozone concentration in tested water increased by 1.8 mg/L under 6 mg/L of ozone dose, probably resulting in the increase of bromate formation potential. This result implies that as alternatives to suppress the bromate formation potential during the oxidation of PPCPs by ozone, investigations on advanced oxidation processes are required.

• Journal of the Korean Applied Science and Technology
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• v.35 no.3
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• pp.757-767
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• 2018

In the propane dehydrogenation reaction proceeding at high temperature, the main cause of deactivation of the catalyst is coke deposition and sintering. In order to investigate the catalysts for reducing such inactivation, we have investigated the applicability of $MgAl_2O_4$ as a carrier for the catalytic dehydrogenation reaction. $MgAl_2O_4$ was prepared by Alcohthermal method at calcination temperature of 800, 900, $1000^{\circ}C$, and $Pt-Sn/MgAl_2O_4$ catalyst was prepared by supporting Pt and Sn by co-impregnation method. The reaction temperature was conducted at a high temperature of 650, $600^{\circ}C$ to confirm the thermal stability. As a result of the reaction experiment, it was confirmed that the conversion rate and yield of propane dehydrogenation reaction test were higher than that of the carrier-applied catalyst having a carrier calcination temperature of 900 and $1000^{\circ}C$, when the carrier-applied catalyst having a calcination temperature of $800^{\circ}C$ was used, It was found that the yield was higher than that of $Pt-Sn/{\theta}-Al_2O_3$ at $650^{\circ}C$. TGA, BET, XRD, CO-chemisorption, and SEM-EDS analyzes were performed for characterization. $MgAl_2O_4-800^{\circ}C$ was correlated with the relationship between good yield, Pt dispersion and low deactivation rate.

• Korean Journal of Weed Science
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• v.6 no.1
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• pp.76-84
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• 1986

All combinations of oxyfluorfen in 5 dosages and glyphosate in 4 dosages were used to assess the onto-drifting pattern of herbicide inactivation in three different type, such as check soil ($O^-M^-$), organic soil ($O^+M^-$), and micro-organism soil ($O^+M^+$). The plant used for bioassay was rape-hybrid. From the results, it was recognized that the herbicide inactivation is strongly achieved in order of $O^+M^+$ > $O^+M^-$ > $O^-M^-$ soil. Also, the inactivation of oxyfluorfen in soil tended to depend rather on soil microorganisms than organic matter, and to be promoted earlier by paraquat mixture than by that of glyphosate. Average 50 and 95% inactivated time (in days) of herbicides were getting shorten in order of $O^+M^+$, $O^+M^-$, $O^-M^-$, rather prolonged in mixture than in oxyfluorfen single treatment, and rather prolonged in high dose than in low dose, respectively.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2004.11a
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• pp.205-206
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• 2004

국내 정수처리에 있어 기존 장티프스, 콜레라 등과 같은 병원성 세균의 소독 뿐만아니라 최근에는 지아디아, 크립토스포리디움과 같은 병원성 원생동물의 불활성화에 대하여 많은 관심을 가져야 하며 적정한 소독능을 확보하기 위해서는 정수지의 도류벽 설치, 용량확장, 수위비조절 및 잔류염소 농도 조절 등의 운영 및 시설개선이 필요한 것으로 판단된다.

• Analytical Science and Technology
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• v.5 no.4
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• pp.471-475
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• 1992

We have developed the methodology for the quantitative analysis of microencapsulation yield and optimized the conditions for the microencapsulation of ${\beta}$-galactosidase by butter oil. The degree of ${\beta}$-galactosidase deactivation by the microencapsulation process was the value of 5.2% of initial activity. And the yield for the microencapsulation of ${\beta}$-galactosidase by the indirect, heat treatment, and enzymatic methodology were 92.6%, 88.6%, and 94.1%, respectively.

• Applied Biological Chemistry
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• v.22 no.1
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• pp.24-27
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• 1979

A study was carried out about the effect of free fatty acids and lecithin on the thermal inactivation of horseradish peroxidase. In presence of lecithin peroxidase was inactivated very rapidly at $70^{\circ}C$ and pH 7.0, and showed also a rapid inactivation curve at $0^{\circ}C$ and pH 4.0. Linoleic acid was more effective in an $O_2-stream$ than in a $N_2-stream$, but oleic acid showed a similar tendency in the presence of $O_2-and\;N_2$ stream. From the results of the experiment we suggested that the opening of the heme crevis of peroxidase in the presence of lecithin and the produced lipidperoxide from linoleic acid may accelerate the thermal inactivation of horseradish peroxidase respectively.

• Journal of Korean Society of Water and Wastewater
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• v.33 no.5
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• pp.379-388
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• 2019

Chlorination and UV illumination are being widely applied to inactivate a number of pathogenic microbials in the environment. Here, we evaluated the inactivation efficiency of individual and combined treatments of chlorination and UV under various aqueous conditions. UV dosage was required higher in waste water than in phosphate buffer to achieve the similar disinfecting efficiency. Free chlorine generated by electrolysis of waste water was abundant enough to inactivate microbials. Based on these, hybrid system composed of sequential treatment of electrolysis-mediated chlorination and UV treatment was developed under waste water conditions. Compared to individual treatments, hybrid system inactivated bacteria (i.e., E. coli and S. typhimurium) and viruses (i.e., MS-2 bacteriophage, rotavirus, and norovirus) more efficiently. The hybrid system also mitigated the photo re-pair of UV-driven DNA damages of target bacteria. The combined results suggested the hybrid system would achieve high inactivation efficiency and safety on various pathogenic microbials in wastewater.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1175-1183
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• 1997

Lethal effects of high voltage pulsed electric fields (PEF) on suspensions of Lactobacillus plantarum cells in phosphate buffer solution were examined by using continuous recycle treatment system. Critical electric field strength and treatment time needed for inactivation of L. plantarum were 13.6 kV/cm and $16.1\;{\mu}s$ at room temperature, respectively. As decrease in frequency (decreasing pulse number), the degree of inactivation of L. plantarum was increased. A 2.5 log reduction in microbial population could be achieved with an electric field strength of 80 kV/cm, 300 Hz frequency and $2000\;{\mu}s$ treatment time. Survivability was decreased with increase in total treatment time (cycle number) and frequency at the same cycle number. As sterilization model of continuous recycle PEF treatment, $logS=-N_m\;log\;m+B$ and $N_m=k_1\;P_n+k_2$ were established. This model was very well fitted to tile empirical data. The rate of inactivation increased with increase in the processing temperature. The maximum reduction in survivability (5.6 log reduction) was obtained with 80 kV/cm electric field strength at $50^{\circ}C$ for $1000\;{\mu}s$ treatment.

• Journal of Plant Biology
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• v.33 no.4
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• pp.277-283
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• 1990

Inactivation and reactivation of photosynthetic oxygen evolving complex were studied with isolated spinach (Spinacia oleraceda. L.) photosystem II particles by the activity of oxygen evolution and chlorophyll fluorescence. When the particles were treated with Tris and urea, the oxygen evolution was inactivated and three polypeptides having molecular weights of 33 kDa, 24 kDa and 18 kDa were simultaneously released. But in NaCl-treated particles, two polypeptides of 24 kDa and 18 kDa were removed from PS II particles. The oxygen evolution activities of Tris and urea-treated particles were not restored by adding cation ions (Mg2+, Mn2+ and Ca2+), but the NaCl-treated particles were restored by exogenously added Ca2+. The removal of these extrinsic polypeptides, especially 33 kDa, markedly showed the decrease of the variable fluorescence (Fv). These results are likely to be due to dissipate thermal energy by antenna of photosystem II complexes.

• Journal of Sericultural and Entomological Science
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• v.51 no.1
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• pp.36-40
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• 2013

To promote the consumption of mulberry fruit, we manufactured mulberry fruit wine with 'simheung' by different processing methods and analyzed cyanidin-3-glucoside(C3G) stability and antioxidant capacity. In the processing of mulberry fruit alcoholic drink, 3 minutes blanching using microwave inhibited the C3G destruction by maintaining the antioxidant capacity and inactivation of enzymes related to pigment's stability. And freeze-dried mulberry fruit was the highest C3G pigment content and antioxidant capacity. Nevertheless, this is not recommended because the economic burden of the cost of freeze-drying. In conclusion, when processing mulberry fruit wine, the addition of citric acid and the enzyme's inactivation treatment were considered more effective than storage containers (transparent glass, brown glass bottles, aluminum foil, green glass, translucent glass bottles).