• Korean Journal of Weed Science
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• v.18 no.1
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• pp.54-62
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• 1998

This experiment was conducted to find out the effects of ABA and IAA on activities of antioxidant enzymes, antioxidant content, and growth of tobacco under exposure to ozone. The exposure to ozone in tobacco plant significantly decreased plant height, but it did not show any difference in vegetative characteristics except plant height of IAA $10^{-3}$M treated. Total chlorophyll content of NC 82 was dramatically decreased with increase in days after ozone treatment. However, reduction of chlorophyll was minimized when plant growth regulators were treated before ozone exposure. Three days treament of ozone in tobacco increased ascorbic acid of oxidised form, while slightly decreased `in reduced ascorbic acid by IAA treatment. But seven days of ozone treatment showed increase in ascorbic acid and decrease in dehydroascorbic acid. Ozone treatment did not show any difference in glutathione content and glutathione reductase activity when plant growth regulators were treated. Activities of superoxide dismutase(SOD), ascorbate peroxidase(AP) and guaiacol peroxidase(GP) were increased by the exposure to ozone for three days. However, there were no difference in activities of SOD, AP and GP due to exposure to ozone for seven days. These reactions may be interpreted as protective responses to prevent or alleviate the damage of tobacco plant by ozone exposure.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.1
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• pp.90-96
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• 2008

To retain the fresh taste and flavor of Kimchi, ozone treatment was applied for kimchi food materials. In this study, Chinese cabbage and salted Chinese cabbage, the highest portion of Kimchi materials, were treated by ozone ($3{\sim}9$ ppm) and their microbiological and chemical characteristics were investigated. Initial number of total aerobic bacteria of Chinese cabbage and salted Chinese cabbage were $1.3{\sim}10^7$ and $7.1{\sim}10^6$ CFU/g, respectively. However, when ozone was treated, the number was decreased and this decrease of bacterial number was maintained during storage. Yeast and mold populations were $6.0{\times}10^3$ and $1.2{\times}10^3$ CFU/g in Chinese cabbage and salted Chinese cabbage, respectively; however, an ozone treatment also decreased the yeast and mold populations. Other physical and chemical characteristics of ozone treated sample such as color, hardness, contents of ascorbic acid and reducing sugar of Chinese cabbage and salted Chinese cabbage were not different when compared with control.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.255-261
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• 2004

Experiments using ozone are presented for the water purification and wine quality improvement. Advanced oxidation process results reveal water treatment by both ozone and UV radiation increases quality of the takju prepared using a Korean conventional nuruk than with ozone-treatment or convectional method only. Water quality was enhanced by ozone treatment, resulting in 85% reduction of hardness, and 30% increase in total glucose produced due to increased conductivity and biodegradability of water. Although initially decreased slightly due to oxidation of takju, higher than expected ethanol production was observed, with ozone plus UV treatment resulting in 20% higher production compared with other methods.

• Korean Journal of Remote Sensing
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• v.36 no.3
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• pp.461-474
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• 2020

Korea launched Geostationary Environmental Monitoring Satellite (GEMS), a UV/visible spectrometer that measure pollution gases on 18 February 2020. Because satellite retrieval is an ill-posed inverse solving process, the validation with ground-based measurements or other satellite measurements is essential to obtain reliable products. For this purpose, satellite-based OMI and OMPS total column ozone (TCO), and ground-based Pandora TCO in Busan and Seoul were selected for future GEMS validation. First of all, the goal of this study is to validate the ground ozone data using characteristics that satellite data provide coherent ozone measurements on a global basis, although satellite data have a larger error than the ground-based measurements. In the cross validation between Pandora and OMI TCO, we have found abnormal deviation in ozone time series from Pandora #29 observed in Seoul. This shows that it is possible to perform inverse validation of ground data using satellite data. Then OMPS TCO was compared with verified Pandora TCO. Both data shows a correlation coefficient of 0.97, an RMSE of less than 2 DU and the OMPS-Pandora relative mean difference of >4%. The result also shows the OMPS-Pandora relative mean difference with SZA, TCO, cross-track position and season have insignificant dependence on those variables.In addition, we showed that appropriate thresholds depending on the spatial resolution of each satellite sensor are required to eliminate the impact of the cloud on Pandora TCO.

• Journal of the Korean earth science society
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• v.21 no.3
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• pp.287-301
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• 2000

In order to investigate the factors and processes affecting the vertical distributions of ozone, we analyzed the ozone profile data measured using ozonesonde from 1995 to 1997 at Pohang city, Korea. In the course of our study, we analyzed temporal and spatial distribution characteristics of ozone at four different heights: surface (100m), troposphere (10km), lower stratosphere (20km), and middle stratosphere (30km). Despite its proximity to a local, but major, industrial complex known as Pohang Iron and Steel Co. (POSCO), the concentrations of surface ozone in the study area were comparable to those typically observed from rural and/or unpolluted area. In addition, the findings of relative enhancement of ozone at this height, especially between spring and summer may be accounted for by the prevalence of photochemical reactions during that period of year. The temporal distribution patterns for both 10 and 20km heights were quite compatible despite large differences in their altitudes with such consistency as spring maxima and summer minima. Explanations for these phenomena may be sought by the mixed effects of various processes including: ozone transport across two heights, photochemical reaction, the formation of inversion layer, and so on. However, the temporal distribution pattern for the middle stratosphere (30km) was rather comparable to that of the surface. We also evaluated total ozone concentration of the study area using Brewer spectrophotometer. The total ozone concentration data were compared with those derived by combining the data representing stratospheric layers via Umkehr method. The results of correlation analysis showed that total ozone is negatively correlated with cloud cover but not with such parameter as UV-B. Based on our study, we conclude that areal characteristics of Pohang which represents a typical coastal area may be quite important in explaining the distribution patterns of ozone not only from surface but also from upper atmosphere.

• Food Science and Preservation
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• v.8 no.4
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• pp.379-384
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• 2001

This study was conducted to investigate the changes in quality of soybean sprouts grown by ozone treatment during storage. Soybean spouts were cultivated under conditions of ozone water watering after soaking in water (W/W), watering after soaking in ozone water (O/W), ozone water watering after soaking in water (W/O) and ozone water watering after soaking in ozone water (O/O). The ozone concentration in soaking of soybean and watering of soybean sprouts was 0.3 ppm, respectively. No significant difference in shelf-life between W/W soybean sprouts and ozone treated samples showed. But shelf-life of soybean sprouts stored in 0.01 ㎜ polyethylene film at 10$\^{C}$ and 20$\^{C}$ prolonged 4 and 2 days, respectively. The slow growth of total microbe in the ozone treated samples stored at 10$\^{C}$ was observed, whereas that of products at 20$\^{C}$ showed rapid growth during storage. However, no great difference occurred among samples in the changes of moisture, vitamin C and chlorophyll content during storage. Higher hardness of soybean spouts stored at 10$\^{C}$ and 20$\^{C}$ was kept in the O/W and W/O products. Color, flavor and overall acceptability evaluated by sensory teat during storage had higher scores in O/W products as compared to the other samples.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.377-378
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• 2000

1957년 국제지구물리관측년 (IGY：International Geophysical Year) 계획 이래 대기중의 오존전량(total ozone)과 대기중의 수직 층별 오존량의 측정을 위해 본격적으로 전세계적 오존관측망이 운영되기 시작하였다. 이 시점을 기준으로 오존에 관한 연구는 전지구적인 오존전량의 감소경향과 남극상공 성층권에서의 오존량 파괴에 집중되어왔다. 그러나 대기중 오존의 행태를 더 정확하게 이해하고, 각각의 대기권이 서로의 오존량에 미치는 영향을 이해하기 위해서는 대기중 오존의 수직분포에 관한 연구가 대단히 중요하다. (중략)

• Journal of the Korean Society of Tobacco Science
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• v.6 no.2
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• pp.215-219
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• 1984

This experiment was conducted to investigate the effect of physical and chemical characteristics of lower grade tobacco with treatment of ozone. In ozonization of low grade tobacco, optimum moisture was 20 percentage, and decrease ratio of content of tobacco leaf was 30 percentage in nicotine , 15.9 percentage in total volatile base, 10.5 percentage in petroleum-ether-extract, 29.5 percentage in solanesol, and decrease ratio of cigarette smoke composition was 31 percentage in nicotine, 6.08 percentage in tar.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.4
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• pp.597-604
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• 2011

This study was performed to compare finished water quality among three different processes. A detailed assessment of performance was carried out during the five months of operation. Finished water quality was evaluated on the basis of parameters such as Dissolved organic carbon (DOC), $UV_{254}$ absorbance, haloacetic acid formation potential (HAAFP), geosmin, 2-methylisoborneol (2-MIB), heterotrophic bacteria and total coliform bacteria. The treatment processes were Process 1 (coagulation-flocculation-sedimentation-sand filtration-ozone-GAC), Process 2 (coagulation-flocculation-sedimentation -microfiltration-ozone-GAC), and Process 3 (coagulation-flocculation-sedimentation- sand filtration-GAC), compared side by side in the pilot testing. Process 2 was found to have better removal efficiency of DOC, $UV_{254}$ absorbance, HAAFP and heterotrophic bacteria in comparison with process 1 and process 3 under identical conditions. Geosmin, 2-MIB and total coliform bacteria were not detected in finished water from each process.

• Journal of Periodontal and Implant Science
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• v.48 no.3
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• pp.136-151
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• 2018

Purpose: The decontamination procedure is a challenging aspect of surgical regenerative therapy (SRT) of peri-implantitis that affects its success. The purpose of the present study was to determine the impact of additional topical gaseous ozone therapy on the decontamination of implant surfaces in SRT of peri-implantitis. Methods: A total of 41 patients (22 males, 19 females; mean age, $53.55{\pm}8.98years$) with moderate or advanced peri-implantitis were randomly allocated to the test group (ozone group) with the use of sterile saline with additional ozone therapy or the control group with sterile saline alone for decontamination of the implant surfaces in SRT of peri-implantitis. Clinical and radiographic outcomes were evaluated over a period of 12 months. Results: At the 12-month follow-up, the plaque and gingival index values were significantly better in the ozone group (P<0.05). Probing depth decreased from $6.27{\pm}1.42mm$ and $5.73{\pm}1.11mm$ at baseline to $2.75{\pm}0.7mm$ and $3.34{\pm}0.85mm$ at the end of the 12-month observation period in the ozone and control groups, respectively. Similarly, the clinical attachment level values changed from $6.39{\pm}1.23mm$ and $5.89{\pm}1.23mm$ at baseline to $3.23{\pm}1.24mm$ and $3.91{\pm}1.36mm$ at the 12-month follow-up in the ozone and control groups, respectively. According to the radiographic evidence, the defect fill between baseline and 12 months postoperatively was $2.32{\pm}1.28mm$ in the ozone group and $1.17{\pm}0.77mm$ in the control group, which was a statistically significant between-group difference (P<0.05). Conclusions: Implant surface decontamination with the additional use of ozone therapy in SRT of peri-implantitis showed clinically and radiographically significant. Trial registry at ClinicalTrials.gov, NCT03018795.