• 한국대기환경학회지
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• 제20권3호
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• pp.345-360
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• 2004

The late sea-breeze and its impacts on ozone distributions were investigated during April to September from 1998 to 2002, in the Busan metropolitan area (including surrounding areas) using the surface ozone concentrations (obtained at 9 monitoring sites), local meteorological variables (obtained near the shore), together with synoptic data. The urban scale ozone concentration was also simulated using the MM5/UAM-V to better understand the role of late sea-breeze in Busan. The results from observation study showed that most of the late sea-breeze occurred when weak offshore synoptic flow (northwesterly) suppressed development of sea - breeze, and the ozone concentration level and frequencies exceeding ozone standard increased with the onset time of sea breeze. We also found that the late sea-breeze clearly induces relatively weak wind speed and high temperature during the daytime As a result it enhances the photochemical ozone accumulation and delays the occurrence time of the averaged maximum ozone concentrations. The results of simulation for high ozone episode (24 August, 2001) by MM5/UAM -V revealed that the late sea-breeze interacted with weak offshore synoptic wind can contribute significantly to high ozone concentration in the coastal urban area. The simulated horizontal and vertical distribution of ozone concentration indicated that ozone can be accumulated over the sea under stagnant condition and return to the land in the late afternoon with the sea breeze, suggesting both the relationship between late sea-breeze and recirculation and the importance of late sea -breeze effects influencing severe ozone pollution in Busan.

• Asian Journal of Atmospheric Environment
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• 제9권1호
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• pp.1-11
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• 2015

Increasing ozone concentrations are observed over Japan from year to year. One cause of high ozone concentration in the Kanto region, which includes areas inland from large coastal cities such as metropolitan Tokyo, is the transportation of precursors by sea breezes. However, high ozone concentrations are also observed in the morning, before sea breezes approach inland areas. In this point, there would be a possibility of residual ozone existing above the nocturnal boundary layer affects the ozone concentration in the following morning. In this study, we utilized the Weather Research and Forecasting model and the Community Multiscale Air Quality model to evaluate the effect of regional precursors and residual ozone on ozone concentrations over the inland Kanto region. The results show that precursors emitted from non-metropolitan areas affected inland ozone concentrations more than did precursors from metropolitan areas. Moreover, calculated results indicate downward transportation of residual ozone, resulting in increased concentration. The residual ozone was also affected by precursors emitted from non-metropolitan areas.

• 한국환경과학회지
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• 제24권1호
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• pp.31-46
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• 2015

In this study, the regional climate (WRF) and air quality (CMAQ) models were used to simulate the effects of future urban growth on surface ozone concentrations in the Seoul metropolitan region (SMR). These analyses were performed based on changes in ozone concentrations during ozone seasons (May-June) for the year 2050 (future) relative to 2012 (present) by urban growth. The results were compared with the impacts of RCP scenarios on ozone concentrations in the SMR. The fractions of urban in the SMR (25.8 %) for the 2050 were much higher than those (13.9 %) for the 2012 and the future emissions (e.g., CO, NO, $NO_2$, $SO_2$, VOC) were increased from 121 % (NO) to 161.3 % ($NO_2$) depending on emission material. The mean and daily maximum 1-h ozone in the SMR increased about 3 - 7 ppb by the effect the RCP scenarios. However, the effect of urban growth reduced the mean ozone by 3 ppb in the SMR and increased the daily maximum 1-h ozone by 2 - 5 ppb over the northeastern SMR and around the coastline. In particular, the ozone pollution days exceeding the 1-h regulatory standard (100 ppb) were far more affected by urban growth than mean values. As a result, the average number of days exceeding the 1-h regulatory standard increased up to 10 times.

• 한국대기환경학회지
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• 제24권3호
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• pp.310-320
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• 2008

Concentration of tropospheric ozone ($O_3$) was investigated for the South Korea. And then the critical ozone levels, expressed as AOT40 (Accumulated exposure over a threshold of 40 ppb) to vegetation have been used in this region within the UNECE (United Nations Economic Commission for Europe) Convention on Long-Range Trans-boundary Air Pollution (CLRTAP). Hourly ozone concentration data from 1996 to 2001 at 26 air monitoring stations was used to estimate the exceedance of the critical levels. It was calculated for daylight hours for each station, and mapped using surface interpolation over the South Korea. The critical levels of ozone have shown the highly exceeded value in the Gyeonggi region, southern coastal region and central inland of the South Korea. It was some different from the typical ozone distribution which represented highly in the western inland and coastal regions. The area exceeding the critical level for crops was founded to be more than 40% of the whole South Korean territory. While that for trees was to be about 17% of the South Korea. The critical ozone critical level was based upon data from experiments on specific species, and thus may not be fully representative for all types of vegetation. Nevertheless, the critical level and its exceedance of the ozone concentration would be one of the useful tools for international agreements on abatement strategies to prevent ecosystem damage.

• 한국구조물진단유지관리공학회 논문집
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• 제22권4호
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• pp.68-75
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• 2018

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 수처리 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 나타났으며 표면처리 방법으로는 테프론계 봉공처리제를 사용하여 마감하는 것이 내오존성 및 부착성능 확보에 가장 적합한 방법이라 판단된다.

• 한국의류산업학회지
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• 제6권4호
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• pp.511-514
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• 2004

We studied on the bleaching properties of silk fabric by vapor type ozone processing using ozone's strong oxidation instead of 28% $H_2O_2$ chemical treatment. When vapor type ozone processing was directly treated to fabrics retaining water to 50~70% pick up ratio, high concentration ozone was generated 14,000ppm(168 mg/h) approximately and finally its bleaching improved. The fabric's bleaching effect was improved because vapor type ozone generated the highest decomposition to oxidation of surface and inter molecules. The experiment revealed that fabric's bleaching was improved by change of the pick-up ratio of vapor type ozone processing. However, tensile strength and elongation were reduced by increase of time, and the time that was assumed as the most optimized time to minimize the reduction of fabric's tensile strength and elongation as well as maximizing the fabric's bleaching was 30 minutes.

• 한국의류산업학회지
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• 제3권4호
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• pp.362-366
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• 2001

We studied on the softness properties of polyester fabric by vapor type ozone processing using ozone's strong oxidation instead of 25% NaOH chemical treatment. When vapor type ozone processing was directly treated to fabrics retaining water to 40% pick up ratio, high concentration ozone was generated oxidation of 3~4% approximately in polyester fabrics and finally its softness improved. The fabric's softness effect was improved because vapor type ozone generated the highest decomposition to oxidation of surface and inter molecules. The experiment revealed that fabric's softness was improved by change of the time of vapor type ozone processing. However, tensile strength and elongation were reduced by increase in time, 60 minute was assumed as the most optimized time to minimize the reduction of fabric's tensile strength and elongation as well as maximizing the fabric's softness.

• 폴리머
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• 제38권5호
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• pp.573-579
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• 2014

탄소나노튜브(CNT), 불소계 아크릴레이트 2,2,2-trifluoroethylmethacrylate(3FMA) 및 유-무기 조성비와 같은 합성조건을 달리하여 제조된 자외선 경화형 유-무기 하이브리드 코팅 막의 표면특성 및 내오존성에 대해 연구하였다. 코팅 막은 금속 알콕사이드 전구체인 tetraethoxysilane(TEOS)와 실란 커플링제인 methacryloyloxypropyltrimethoxysilane (MPTMS)로 구성된 유-무기 혼성 용액에 탄소나노튜브 및 3FMA와 자외선 경화를 위한 유기물을 첨가하여 제조된 코팅제를 자외선 경화시켜 제조하였다. 제조된 코팅 막의 내오존성 및 기재와의 접착력은 TEOS, 3FMA 및 CNT의 함량에 크게 영향을 받는다는 것을 확인하였다. 특히, 탄소나노튜브가 첨가된 코팅 막은 우수한 내오존성 및 접착력 뿐만 아니라 높은 표면경도를 나타내었다. TEOS의 경우, 함량이 증가할수록 표면경도 및 내오존성은 향상되었지만, 기재와의 접착력은 감소되었다. 불소아크릴레이트 3FMA의 경우, 함량이 증가할수록 내오존성은 향상되었지만 표면경도는 감소하였다.

• 한국안전학회지
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• 제14권3호
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• pp.63-68
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• 1999

In this paper, characteristics of ozone generation by using coil and SPCP + DC corona reactor was studied. The ceramic-based surface discharge electrode, which was first invented as a high-efficiency ozonizer, has been used as an experimental plasma chemical reactor.(Surface Induced Plasma Chemical Processing, SPCP.) The electrode, however, has a structural disadvantage that a highly energetic plasma region is localized near the electrode surface, which may make it impossible for higher efficiency to realize. In an attempt to overcome this advantage, we have developed a hybrid reactor which employs a corona discharge unit together with the surface discharge unit. Experimental results suggest that the efficiency of the ozone production rate is improved when positive corona discharge is added.

• Journal of Korean Society for Atmospheric Environment
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• 제18권E3호
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• pp.129-142
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• 2002

This paper provides a long-term perspective for ozone concentrations at 20 national air quality monitoring sites in Seoul from 1989 to 1998, which were managed by the Korean Ministry of Environment. Ozone episodes occurred more frequently in the east areas (Bangi, Guui, Seongsu, and Ssangmun) than in the west area (Guro and Oryu). When an ozone episode happened, hourly ozone concentrations over 80 ppb continued for an average of 4.0 hours at all sites. Annual variations in daily mean and maximum oBone concentrations showed broadly consistent upward trends at Ssangmun and Gwanaksan. Monthly mean ozone concentrations were the highest from May to June and the 99$^{th}$ and 95$^{th}$ percentile levels appeared higher during June, July, and August. The diurnal patterns of hourly mean ozone levels in urban areas showed typical photochemical formation and destruction, while the flat diurnal shape before 1996 at Gwanaksan indicated few significant photochemical reactions due to a lack of precursors of ozone. The occurrence of ozone over 80 ppb was ascribed to meteorological conditions such as high temperature, strong solar radiation, low relative humidity, and low wind speed with winds most frequently in a westerly direction.