• Title/Summary/Keyword: 내오존

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Effect of Ozone on Gas Separation Membranes for On-Board Inert Gas Generation System (OBIGGS) (OBIGGS용 기체 분리막에서 오존이 미치는 영향)

  • Jung, Kyung Nam;Woo, Seung Moon;Kim, Se Jong;Kim, Ji Hyeon;Han, Sang Hoon;Nam, Sang Yong
    • Membrane Journal
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    • v.28 no.6
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    • pp.406-413
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    • 2018
  • In OBIGGS, a small amount of ozone in the atmosphere damages the polymer membrane. Therefore, the ozone removal device is installed at the front end to prevent the damage of the membrane by reducing the concentration of ozone in the gas delivered to the membrane. In this study, two hollow fiber membranes, PI and PSf, used to fabrication hollow fiber module with an effective membrane area of $6.37cm^2$ for gas separation in OBIGGS. The ozone concentration in the chamber was maintained at 2-3 ppm. The gas was continuously supplied into the module by using a pump. The gas permeation characteristics and the tensile strength were evaluated as a function of ozone exposure time. The PI-based hollow fiber membrane showed only 20% reduction in the transmittance, and remained its original uniformity without any significant changes. However, when PSf type hollow fiber membranes were used, the permeability decreased by more than 80% and the tensile strength decreased by more than 70%.

Effect of Operating Parameters on Ozone Generation in Dielectric Barrier Discharge Process (무성방전내에서 오존 발생에 미치는 운전변수의 영향)

  • 이현돈;이은영;이용환;최유리;정재우
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.05b
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    • pp.383-384
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    • 2003
  • 오존은 산업적으로 널리 활용되고 있으며 특히, 매우 넓은 환경공학적 응용분야를 가지고 있다. 오존의 산업적 적용은 1900년대 초부터 음용수 처리를 위해 시작되었으며 현재까지 폐수처리, 화학물질 합성, 재료의 부식 정도 측정, 수영장 소독, 치료용 목적, 냉각수 살균, pulp bleaching, 악취 및 대기 오염물질 처리 등의 광범위한 산업적 응용분야를 가지고 있다. 오존을 생성시키기 위한 대표적인 공정으로는 무성방전(dielectric barrier discharge, DBD) 공정, 전기 분해법(electrolysis), 자외선 조사법(UV irradiation)을 들 수 있으며 가장 널리 활용되고 있는 공정은 1857년 Simens에 의해 개발된 DBD 공정이다. (중략)

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Optimal Conditions for Improving Enzyme Preteatment Efficiency in Sludge Reduction Process. (슬러지 저감시 효소 전처리의 효율 향상 및 최적화 연구)

  • 김정래;심상준
    • Microbiology and Biotechnology Letters
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    • v.32 no.2
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    • pp.166-171
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    • 2004
  • In this study, we introduced enzymatic pretreatment method, together with ozone treatment for sludge digestion. We optimized the amount of enzyme and ozone, respectively for the successful sludge pretreatment. As a result, we found that as more enzyme is used, higher sludge hydrolysis efficiency was obtained. When we treated sludge by ozone ranging from 0.01g $O_3$/g SS to 0.04 g $O_3$/g SS without enzyme treatment, 0.04 g $O_3$/g SS showed the highest increase of SCOD. Meanwhile, when protease was used together with the same ozone dosage ranges, 0.03g $O_3$/g SS ozonation resulted in the highest increase of SCOD. The sludge pretreatment was optimized by controlling the amount of enzyme and ozone.

Air Pollution Tolerance Index (APTI) of Main Street Trees Following Ozone Exposure (주요 가로수 묘목의 오존노출에 따른 대기오염내성지수 비교)

  • Cho, Su Bin;Lee, Hyung Sup;Lee, Jong Kyu;Park, Sang Hee;Kim, Han Dong;Kwak, Myeong Ja;Lee, Keum Ah;Lim, Yea Ji;Woo, Su Young
    • Journal of Korean Society of Forest Science
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    • v.109 no.1
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    • pp.50-61
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    • 2020
  • Street trees are very important to urban environments as they can alleviate air pollution. However, when ozone is absorbed through the stomata, it can induce the formation of free radicals inside the tree, negatively affecting the vegetation. The present study investigated the Air Pollution Tolerance Index (APTI) of four major street tree species: Prunus yedoensis, Zelkova serrata, Chionanthus retusus, and Pinus densiflora. Two-year-old seedlings were placed in a phytotron and fumigated with 100 nL·L-1 (ppb) ozone for 4 weeks, following which the ascorbic acid contents, chlorophyll contents, leaf pHs, and relative water contents were measured. There was no significant difference in the APTI of Prunus yedoensis and Zelkova serrata between the ozone and control treatments. By contrast, the ozone treatment caused the APTI of Chionanthus retusus to increase and that of Pinus densiflora to decrease compared with the respective controls. These results suggest that the APTI of these tree species exhibit very different responses to ozone. Therefore, more detailed research should be conducted on a range of species in the future.

A Study of Characteristic of Oriental Herbal Medicine Storage System using Ozone Lamp (오존램프를 이용한 한약재 저장 장치의 특성 연구)

  • Woo, Sung-Hun;Lee, Kwang-Sik
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.21 no.1
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    • pp.98-103
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    • 2007
  • We made a oriental herbal medicine storage system and studied a preservation characteristic of oriental herbal medicine in this research. The lamp(OZ-Lamp) in a storage system is the low pressure ultraviolet lamp which radiates the sterilizing and ozonic rays. We made research ozone generation and electric discharge characteristic of a oriental herbal medicine storage system, which have radiation feature of ultraviolet rays of a short wavelength to be happened in the electric discharge. Also, we made research an ingredient and quality characteristic of oriental herbal medicine according to ozone treatment storage.

Prediction of Ozone Formation Based on Neural Network and Stochastic Method (인공신경망 및 통계적 방법을 이용한 오존 형성의 예측)

  • Oh, Sea Cheon;Yeo, Yeong-Koo
    • Clean Technology
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    • v.7 no.2
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    • pp.119-126
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    • 2001
  • The prediction of ozone formation was studied using the neural network and the stochastic method. Parameter estimation method and artificial neural network(ANN) method were employed in the stochastic scheme. In the parameter estimation method, extended least squares(ELS) method and recursive maximum likelihood(RML) were used to achieve the real time parameter estimation. Autoregressive moving average model with external input(ARMAX) was used as the ozone formation model for the parameter estimation method. ANN with 3 layers was also tested to predict the ozone formation. To demonstrate the performance of the ozone formation prediction schemes used in this work, the prediction results of ozone formation were compared with the real data. From the comparison it was found that the prediction schemes based on the parameter estimation method and ANN method show an acceptable accuracy with limited prediction horizon.

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Anti-microbial Activity Effects of Ozonized Olive Oil Against Bacteria and Candida albicans (오존화 올리브 오일의 세균과 Candida alicans에 대한 항미생물 활성 효과)

  • Chung, Kyung Tae;Kim, Byoung Woo
    • Journal of Life Science
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    • v.29 no.2
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    • pp.223-230
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    • 2019
  • Ozone is a gaseous molecule able to kill microorganisms, such as yeast, fungi, bacteria, and protozoa. However, ozone gas is unstable and cannot be used easily. In order to utilize ozone properly and efficiently, plant oil can be employed. Ozone reacts with C-C double bonds of fatty acids, converting to ozonized oil. In this reaction, ozonide is produced within fatty acids and the resulting ozonized oil has various biological functions. In this study, we showed that ozonized oil has antimicrobial activity against fungi and bacteria. To test the antimicrobial activity of ozonized oil, we produced ozonized olive oil. Ozonized olive oil was applied to Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. Antimicrobial activity was assayed using the disk diffusion method following the National Committee for Clinical Laboratory Standards. Minimal inhibitory concentrations (MIC) were 0.25 mg for S. aureus, 0.5 mg for S. epidermidis, 3.0 mg for P. aeruginosa, and 1.0 mg for E. coli. Gram positive bacteria were more susceptible than Gram negative bacteria. We compared growth inhibition zones against S. aureus and MRSA, showing that the ozonized olive oil was more effective on MRSA than S. aureus. Furthermore, the ozonized olive oil killed C. albicans within an hour. These data suggested that ozonized olive oil could be an alternative drug for MRSA infection and could be utilized as a potent antimicrobial and antifungal substance.