본 연구진은 포항지역을 중심으로 1995년부터 1997년의 3년간 오존존데로 관측한 고도별 오존농도 및 오존전량 자료를 이용하여 오존의 수직분포특성에 대한 연구를 수행하였다. 오존의 수직분포를 체계적으로 밝히기 위해, 지상(100m), 대류권(10km), 하부 성층권(20km), 중부 성층권(30km)을 대표 고도로 설정하여 오존농도의 시 · 공간적 분포특성에 대한 비교분석을 시도하였다. 지상(100m) 오존의 경우, 포항제철이 인접해 있음에도 불구하고, 전반적으로 청정지역에서와 유사한 농도분포를 유지하였다. 봄과 여름에 높고 가을과 겨울에 낮은 농도분포는 기상인자들과의 상관성을 고려할 때, 대체로 광화학 반응에 의한 결과로 보여진다. 대류권(10km) 및 하부 성층권(20km)의 경우 춘고하저(春高夏低)의 전형적인 북반구 대류권 오존의 시간적 경향성을 나타내었다. 이는 고도별 오존농도간의 분석결과 성층권 오존의 대류권 이동 및 광화학 반응과 역전층 형성에 의한 결과로 추정된다. 중부 성층권(30km) 오존의 경우 지상 오존의 농도분포 경향과 매우 유사한 월주기 및 계절주기를 취하였다. Brewer 분광광도계에 의한 오존전량은 성층권 오존량 (Umkehr 법)에 의해 크게 좌우되며, 오존전량은 유해자외선 (UV-B)과의 상관성은 미미하나, 운량과는 음의 상관성을 갖는 것으로 나타났다. 본 연구의 결과 지상권뿐만 아니라 대류권 및 성층권 오존의 시간적 특성을 이해하는데 있어 포항이 해안도시라는 지리학적인 요인이 매우 중요하다는 점을 확인할 수 있다.

본 연구는 반도체 공정중 습식세정시 사용되는 초순수내에서의 오존의 거동과 오존이 주입된 초순수와 실리콘 웨이퍼와의 반응성에 대해 연구하였다. 초순수내 오존의 용해도는 주입되는 오존의 농도와 초순수의 온도가 낮을수록 증가하였고 주입되는 오존의 농도에 정비례하여 증가하였다. 초순수내 오존의 반감기는 초순수내 오존의 용해농도와 초순수의온도가 낮을수록 증가함을 나타내었고 반응차수는 약 1.5로 계산되었다. 초순수의산화환원전위(redox potential)값은 오존 주입시 5분 이내에 포화되어 일정한 값을 나타내었고 주입되는 오존의 농도가 증가함에 따라 약간 증가하였다. HF처리된 실리콘 웨이퍼는 오존이 2ppm 이상 용해된 초순수에서 세정하였을 때 1분 이내에 접촉각이 10˚미만의 친수성 표면을 형성하였고 piranha 세정액(H2SO4과 H2O2의 혼합액)에 의해 형성된 자연산화막보다 오존이 주입된 초순수에 의해 형성된 산화막이 약간 더 두꺼움을 Spectroscopic Ellip-someter에 의해 관찰하였다. 오존의 농도가 1.5ppm에서 90초내에 계면활성제로 오염된 실리콘 웨이퍼를 piranha용액과 오존이 함유된 황산 그리고 오존이 함유된 초순수에서 세정시 오존이 함유된 초순수가 가장 탁월한 오염제거능력을 나타내었다.

For the purpose of improving hygienic quality of dried-Angelica Keiskei Koidz powder, the effects of ozone treatment and gamma irradiation on the microbial decontamination and physicochemical properties were investigated. Gamma irradiation at 5 to 7.5 kGy resulted in sterilizing total aerobic bacteria, molds and coliforms below detective levels, while ozone treatment for 8 hours up to 18 ppm did not sufficiently eliminate the total aerobic bacteria of the sample. The physicochemical properties of the sample were not changed by gamma irradiation up to 7.5 kGy, whereas, ozone treatment caused remarkable changes in pH, TBA value, chlorophyll, carotenoid and fatty acid compositions. Therefore, this investigation demonstrated conclusively that gamma irradiation was more effective than ozone treatment for decontaminating and sterilizing the dried-Angelica Keiskei Koidz powder, with minimal effect on the physicochemical properties analyzed.

반도체 소자가 고집적화 됨에 따라 단위공정의 수가 증가하게 되었고 동시에 실리콘 기판의 오염에 대한 문제가 증가하였다. 실리콘 기판의 주 오염물로는 유기물, 파티클, 금속분순물 등이 있으며 특히, Cu와 Fe과 같은 금속불순물은 이온주입 공정, reactive ion etching, photoresist ashing과 같은 실 공정 중에 1011-1013atoms/㎤정도로 오염이 되고 있다. 그러나 금속불순물 중 Cu와 같은 전기음성도가 실리콘 보다 큰 오염물질은 일반적인 습석세정방법으로는 제거하기 힘들다. 따라서 본 연구에서는 Cu와 Fe과 같은 금속불순물을 제거할 목적을 건식과 습식 세정방법을 혼합한 UV/ozone과 HF세정을 제안하여 실시하였다. CuCI2와 FeCI2 표준용액으로 실리콘 기판을 인위적 오염한 후 split 1(HF-only), split 2 (UV/ozone+HF), split 3 (UV/ozone + HF 2번 반복), split 4(UV/ozone-HF 3번 반복)를 실시하였고 TXRF(Total Reflection X-Ray Fluorescence)와 AFM(Atomic Force Microscope)으로 금속불순물 제거량과 표면거칠기를 각각 측정하였다. 또한 contact angle 측정으로 세정에 따른 표면상태도 측정하였다. TXRF 측정결과 split 4가 가장 적은 양의 금속불순물 잔류량을 보였으며 AFM 분석을 통한 표면거칠기도 가장 작은 RMS 값을 나타내었다. Contact angle 측정 결과 UV/ozone 처리는 친수성 표면을 형성하였고 HF처리는 소수성 표면을 형성하였다.

For the purpose of improving hygienic quality of health-foods, sterilization effects of y ray and ozone on microoganisms associated with food cultured in the media and contaminated in Angelica keiskei powder were investigated. Ozone was immersed in water and sprayed in air, on the concentration of 3 mg liter^(-1) at an air flow rate of 5 liter min'. Test strains cultured in the media completely inhibited by γ-ray at irradiation doses of 0.25--2 kGy. In the case of ozone, test bacteria inactivated after treatment of 10-20 minutes, but test mold, Aspergillus llavus was not effective. Strains contaminated in Angelica keiskei powder completely inhibited by γ-ray at irradiation doses of 2.5-7.5 kGy. However, when the powder was sprayed with ozonized air for 10 hours, Bacillus subtilis and Staphylococcus aureus among five strains were eliminated.

As a preliminary experiment to investigate the effect of ozone sterelization on the ginseng powder, the changes of fatty acid composition and organic acid content and sensory properties in ginseng powder treated with ozone was investigated. Ginseng powder was treated with 0.5 ppm ozone for 24 hours and 48 hours, respectively. With increase in ozone treatment time, the content of crude lipid and total unsaturated fatty acid decreased, whereas composition of total saturated fatty acid increased. Contents of unsaturated fatty acid-linolenic acid, linoleic acid, and oleic acid, etc.-decreased with ozone treatment time, whereas saturated fatty acid of same number-stearic acid-increased. Contents of organic acid were not shown significant changes. Ginseng odor, roasted odor, bitter taste, roasted taste and sweet taste were thicker with ozone treatment times, but pungent taste was thicker with those treatment. These changes of ordors and tastes of ginseng powder with ozone treatment were predicted by oxydation of lipids, flavor components and saponins.

A study on the fouling control by periodical ozone-scrubbing was conducted in a membrane filtration process for drinking water treatment. Hydrophilic hollow fiber polyethylene membrane with pore size of $0.1{\mu}m$ and its surface area of $0.42m^2$ was used. Dead-End filtration method was selected to obtain high efficiency of energy. Laboratory prepared synthetic raw water with kaolin was used and the membranes were scrubbed by ozone once in an hour and once in two hours. When the duration of ozone scrubbing was increased from 10 seconds to 20 seconds, the rate of membrane fouling was significantly decreased. Although the frequency of ozone-scrubbing was reduced from once in an hour to once in two hours. the effect of fouling control was unchanged. However, ozone-scrubbing was not effective after a membrane was fouled and washed with detergent for reuse. Among several possible working effects of ozone, bactericidal effect was confirmed to be the primary reason of fouling control.

Ozone treatment was applied to ginseng powder for the improving hygienic quality of ginseng powder. A bacterial strain was isolated form ginseng powder contaminated. The strain designated as GT4, was identified as Escherichia coli species by IMVIC test method. Ozone inhibited strongly total bacteria and coliforms in ginseng powder(initial concentration 10³/g) at 0.35 ppm. High ozone concentration reduced death time of the total bacteria in ginseng powder. However, ozone treatment caused significant degradation in saponins of ginseng powder. Ozone treatment also caused a increase in Hunter's color L value and decrease in a and b values of ginseng powder.

This study analyzed characteristics of ozone (O3) formation regimes in Busan over a period of recent five years (2015~2019) and compared the findings with those obtained in Seoul. We employed four observed variations: early morning commuting-hour (i.e., 06:00-09:00 LST) nitrogen dioxide (NO2), peak-hour (i.e., 12:00-16:00 LST) O3, 8-hour average O3 (MDA8 O3), and △O3 (=O3_max- O3_min) in Busan and Seoul. In addition, the NO2-O3 relation was assessed to interpret which of NOx-limited or volatile organic compound (VOC)-limited was dominant. In Busan, the annual mean O3 concentration was relatively higher than in Seoul, whereas there were fewer high-concentration days. The Pearson correlation coefficients (R) between Early morning-hour NO2 and the Peak-hour O3 was positive (but close to zero) in Busan and negative in Seoul. Likewise, the R between the Early morning-hour NO2 and the △O3 showed a relatively considerable positive correlation (R=+0.4~0.5) in Busan, while a weak positive correlation (R=+0.1~0.2) in Seoul. From this result, it can be inferred that the O3 formation regime in Busan was intrepreted to be nearly neutral or relatively closer to the NOx-limited regime than Seoul, while Seoul to the VOC-limited regime. The study findings imply that O3 control strategies should be applied differently in Busan and Seoul. The results here were inferred from surface NO2 and O3 observations, and the varification studies based on in-situ VOCs measurements would be needed.

The purpose of this study was to develop a recycling system for ozone off-gas. Although the ozone transmission rate of the injector method differs slightly depending on the ozone injection rate, it reaches approximately 99%, which is very high. During the increase in water inflow to the ozone recycling system from 2 L/min to 10 L/min, the average ozone recycling rate was 99.4% at a 1 ppm ozone injection rate, 98.6% at a 2 ppm ozone injection rate, 98.1% at a 3 ppm ozone injection rate. Ozone treatment facility operating costs can be divided into the costs of pure oxygen production, ozone production, and maintenance. The annual operating costs of ozone treatment facilities in Korea are estimated to be approximately 38.9 billion won. The annual savings are estimated to be approximately 5.8 billion won when the ozone transfer rate of the diffuser method, which is mostly employed in domestic water treatment plants, is 85% and 15% of the ozone is recycled.

In this study, we quantitatively analyze the effect of ocean emission sources on the simulated O3 concentrations in South Korea using the community multi-scale air quality (CMAQ) model. To analyze changes in O3 concentrations by ocean emissions, two different CMAQ simulations considering ocean emissions (OE case) and without considering ocean emissions (NE case) were conducted during the Korea-United States air quality (KORUS-AQ) campaign period (May–June 2016). The changes in the simulated O3 concentrations due to the effect of ocean emissions (OE case-NE case) appeared mostly in the ocean areas (+1.201 ppbv). The effect of ocean emissions was positive during the daytime (+1.813 ppbv), but negative during the nighttime (–0.612 ppbv). Analysis using the integrated process rate (IPR) confirmed that the increase or decrease in O3 concentration by ocean emissions was mainly due to chemical processes. Further analysis using the integrated reaction rate (IRR) showed that the daytime increase in O3 concentration was mainly attributable to the increased O3 production via O + O2 + M → O3 + M reaction as photolysis of NO2 increased due to the added ocean emissions. The nighttime decrease in O3 concentration was mainly due to the increased O3 titration by NO (NO + O3 → O2 + NO2) due to the increased NO emission. These results indicate that the changes in the concentration O3 in the sea area by the effect of ocean emissions are mainly due to increased NOx emissions. However, there could be a number of uncertainties in ocean emissions data used in this study, thus continuous comparative research using the most updated data will need to be carried out in the future.

We analyze the observations of temperature and ozone measured by the Microwave Limb Sounder (MLS) during the period of 2005–2016, to investigate the vertical structures of temperature and ozone in the stratosphere and mesosphere during stratospheric sudden warming (SSW). We compute the height profiles of the correlation coefficients between 55 height levels of MLS temperature anomalies and compare them with the results of Whole Atmosphere Community Climate Model simulations for three major SSWs. We also construct the temperature and ozone anomalies for the events to investigate the changes in the temperature and ozone distributions with height. There seems to always be a relatively weak but broad negative correlation between the temperature anomaly at 10 hPa and temperature anomalies over the entire mesosphere during the period before SSW events. However, this pattern gets stronger in the lower mesosphere but becomes a positive correlation in the upper mesosphere and lower thermosphere after the onset of SSW. We also found that the temperatures from the simulations show a similar trend to the observational results but with smaller variations and the transition height from negative to positive correlation in the mesosphere is much lower in the simulation than in the actual observations.

산업화, 도시화로 인해 수자원의 오염이 악화 되면서 기존에 염소를 이용한 정수처리 방법으로는 깨끗한 물을 공급하는데 어려운 실정이다. 이에 오존을 이용한 고도정수 처리 시설의 도입이 증가하고 있다. 그러나 기존의 방수⋅방식 공법으로 사용되는 에폭시계 방수⋅방식제 및 스테인리스는 오존의 강력한 산화력으로 인해 열화되어 박리 등 문제 발생하였으며, 콘크리트까지 영향을 미쳐 내구성 저하의 원인이 된다. 이에 따라 본 연구에서는 내오존성 및 내화학성이 뛰어난 금속 패널을 기존의 시공법 보다 손쉬운 방법으로 시공하기 위한 방법으로 금속용사 공법을 이용하여 수처리 시설 콘크리트 구조물의 열화를 원천적으로 방지하기 위한 마감공법 개발 연구의 일원으로 용사금속 종류 에 따른 내오존성 평가를 실시하였으며, 실제 하수처리장 환경에서의 전기화학적 안정성능 평가를 실시하였다. 실험결과 용사금속 Ti이 용사 후에도 내오존성이 뛰어난 것으로 나타났으며, 하수처리장 환경에서의 전기화학적 안정성능 평가 결과 용사금속 Ti가 403.83k∙ Ω∙cm2의 가장 높은 분극저항을 나타남으로써 높은 수준의 내구성을 확보하는 것을 확인할 수 있었다.

In this study, the impacts of local meteorology caused by tidal changes in the West Sea on ozone distributions in the Seoul Metropolitan Area (SMA) were analyzed using a meteorological model (WRF) and an air quality (CMAQ) model. This study was carried out during the day (1200–1800 LST) between August 3 and 9, 2016. The total area of tidal flats along with the tidal changes was calculated to be approximately 912 km2, based on data provided by the Environmental Geographic Information Service (EGIS) and the Ministry of Oceans and Fisheries (MOF). Modeling was carried out based on three experiments, and the land cover of the tidal flats for each experiment was designed using the coastal wetlands, water bodies (i.e., high tide), and the barren or sparsely vegetated areas (i.e., low tide). The land cover parameters of the coastal wetlands used in this study were improved in the herbaceous wetland of the WRF using updated albedo, roughness length, and soil heat capacity. The results showed that the land cover variation during high tide caused a decrease in temperature (maximum 4.5℃) and planetary boundary layer (PBL) height (maximum 1200 m), and an increase in humidity (maximum 25%) and wind speed (maximum 1.5 ms-1). These meteorological changes increased the ozone concentration (about 5.0 ppb) in the coastal areas including the tidal flats. The increase in the ozone concentration during high tide may be caused by a weak diffusion to the upper layer due to a decrease in the PBL height. The changes in the meteorological variables and ozone concentration during low tide were lesser than those occurring during high tide. This study suggests that the meteorological variations caused by tidal changes have a meaningful effect on the ozone concentration in the SMA.

Temporal and spatial variations in surface ozone concentrations in Busan were investigated by using observation data from urban air quality sites during 2001-2016. The annual ozone concentrations showed a significant increasing trend of +0.40 ppb yr-1 in this period, with a more rapid increase of +0.81 ppb yr-1 since 2010. For the monthly analysis, the increase in ozone concentration was the greatest in August (+0.68 ppb yr-1). These ozone trends were due mainly to rising temperature (+0.05℃ yr-1) and weak decreasing precipitation (－6.42 mm yr-1). However, the extreme weather events (heat wave, localized heavy rain, etc.) lead to an increase in short-term variability of ozone since 2010. The relatively low ozone concentrations in the downtown area were caused by high NOx emissions from mobile sources. The increases in ozone concentrations were observed at most of the air quality monitoring sites due to the reductions in anthropogenic emissions of NOx during 2001-2015. However, in the southern coastal area, lower rates of increase in ozone concentrations were observed by –0.10~0.25 ppb yr-1 due to the significant NOx emitted by ships in the Busan port and Busan new port.

기존의 정수처리 방법으로는 제거되지 않는 물질이 발생함에 고도정수 처리 시설의 도입이 증가하고 있다. 그러나 오존을 이용한 고도정수처리 시설의 내부 방수·방식재는 오존의 산화력에 의해 열화되며 콘크리트까지 영향을 미쳐 내구성 저하의 원인이 된다. 본 연구에서는 내오존성 및 내화학성이 뛰어난 금속 패널을 기존의 시공법 보다 손쉬운 방법으로 시공하기 위한 방법으로 금속용사 공법을 이용하여 수처 리 시설 콘크리트 구조물의 열화를 원천적으로 방지하기 위한 마감공법 개발 연구의 일원으로 용사금속 종류 및 피막의 표면처리 방법에 따른 내오존성 평가를 실시하였으며, 오존처리 후의 부착강도를 평가하였다. 실험결과 용사금속 Ti이 용사 후에도 내오존성이 뛰어난 것으로 나타 났으며 표면처리 방법으로는 테프론계 봉공처리제를 사용하여 마감하는 것이 내오존성 및 부착성능 확보에 가장 적합한 방법이라 판단된다.

Background : Tropospheric ozone (O3) is a secondary air pollutant that negatively affects numerous agricultural crop and forest. The tropospheric ozone is constantly increasing due to fossil fuel air pollutants. Here, we study the response of tartary buckwheat to ozone gas includes physiological and biochemical changes such as change in gene expression and metabolism. Methods and Results : Tartary buckwheat plants have green stems and leaves under normal conditions, while the plants exposed to the ozone have red stems and reddish green leaves. The expression of most flavonoid biosynthetic genes were significantly upregulated in ozone-treated buckwheat plants, exceting the expression of FtF3’H2. The contents of two anthocyanins, cyanidin 3-O-glucoside and cyanidin 3-O-rutinoside, were significantly increased by ozone treatment. From the metabolic profiling based on the GC-TOF-MS analysis, we identified the effect of ozone on thirty-five metabolites, including sugars, amino acids, and organic acids. Most of the metabolites result in significantly decreased or nearly remain unchanged in the ozone-treated plants compared with untreated plants, excepting alanine, proline, tryptophan, sucrose, and raffinose. To identify the effect of ozone on the leaf, we analyzed the epidermal cells on the leaf surface by scanning electron microscopy. Interestingly, amount of epidermal cells were partially destructed in ozone-treated plants. Conclusion : By analyzing both primary and secondary metabolites of tartary buchwheat without or with ozone, we identified that ozone affects the modulation of the metabolites as well as gene expression in tartary buchwheat.

Recently, Advanced water treatment facilities with Ozone are being introduced domestically. However, waterproofing/corrosion prevention construction method of concrete structure for existing advanced water treatment makes waterproofing/corrosion prevention materials and concrete deteriorated because of strong oxidation of ozone. Therefore, in this study, It was evaluated in Permeability Evaluation of metal spraying coating.

Meteorological characteristics related to variations in ozone (O3) concentrations in the Korean peninsula before, during, and after Typhoon Talas (1112) were analyzed using both observation data and numerical modeling. This case study takes into account a high O3 episode (e.g., a daily maximum of ≥90 ppb) without rainfall. Before the typhoon period, high O3 concentrations in the study areas (e.g., Daejeon, Daegu, and Busan) resulted from the combined effects of stable atmospheric conditions with high temperature under a migratory anticyclone (including subsiding air), and wind convergence due to a change in direction caused by the typhoon. The O3 concentrations during the typhoon period decreased around the study area due to very weak photochemical activity under increased cloud cover and active vertical dispersion under a low pressure system. However, the maximum O3 concentrations during this period were somewhat high (similar to those in the normal period extraneous to the typhoon), possibly because of the relatively slow photochemical loss of O3 by a H2O + O(1D) reaction resulting from the low air temperature and low relative humidity. The lowest O3 concentrations during the typhoon period were relatively high compared to the period before and after the typhoon, mainly due to the transport effect resulting from the strong nocturnal winds caused by the typhoon. In addition, the O3 increase observed at night in Daegu and Busan was primarily caused by local wind conditions (e.g., mountain winds) and atmospheric stagnation in the wind convergence zone around inland mountains and valleys.

The classification of airflow patterns during high ozone (O3) and PM10 episodes on Jeju Island in recent years (2009-2015), as well as their correlation with meteorological conditions according to classified airflow patterns were investigated in this study. The airflow patterns for O3 and PM10 were classified into four types (Types A-D) and three types (Types E-G), respectively, using the HYbrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model and synoptic weather charts. Type A was the most dominant airflow pattern for O3 episodes, being characterized by the transport of airflows from urban and industrial areas in China with the highest frequency (about 69%, with a mean of 67 ppb). With regard to the PM10 episodes, Type E was the most dominant airflow pattern, and was mostly associated with long distance transport from Asian dust source regions along northwesterly winds, having the highest frequency (about 92%, with a mean of 136 μg/m3). The variations in the concentration of O3 and PM10 during the study period were clarified in correlation with two pollutant and meteorological variables; for example, the high (low) O3 and PM10 concentrations with high (low) air temperature and/or wind speed and vice versa for precipitation. The contribution of long-range transport to the observed PM10 levels in urban sites for different airflow patterns (Types E-F), if estimated in comparison to the data from the Gosan background site, was found to account for approximately 87-93% (on average) of its input. The overall results of the present study suggest that the variations in O3 and PM10 concentrations on Jeju Island are mainly influenced by the transport effect, as well as the contribution of local emissions.