• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 총회 및 춘계학술발표회
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• pp.140-143
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• 2001

The packed column experiments were conducted with commercial Jumunjin sand(SOM content : 0.01 %) and a field soil(SOM content : 0.08 %) in order to understand the effects of water content and soil organic matter(SOM) on the transport of gaseous ozone in unsaturated soil contaminated with phenanthrene. Water content and SOM content were artificially controlled. As water content increased, earlier breakthrough was observed in the beginning of BTC of ozone, because direct contact of gaseous ozone with SOM and phenanthrene was prevented by water film formed between soil particles and gaseous ozone. The total removal of phenanthrene in Jumunjin sand was not affected by water content which was more than 99% at different water content(4.4, 8, 17.3%). However, the removal in field soil at water content 6.5 % and 20 % was 98% and 80 %.

• 동아시아식생활학회지
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• 제4권2호
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• pp.69-74
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• 1994

In order to improve the shelf-life of Tofu, the elimination of contaminated bacteria by ozone treatment was examined. Tofu prepared from ozone treated-soybean was investigated for microbial, physicochemical and sensory changes during storage at 20$^{\circ}C$ and 30$^{\circ}C$. As a result of treatment in ozonic water by 2~4ppm/sec for 3 hours, 90~98% of the total bacteria in material soybean for Tofu was eliminated. At 20$^{\circ}C$, control Tofu prepared from ozone treated-soybean was found to be spoiled after 72 hous. Titratable acidity and sensory changes of Tofu was increased as spoilage of Tofu was progressed, but pH was decreased at the first day of storage, and after that it was increased. At 30$^{\circ}C$, there was no remarkable difference between Tofu of control and Tofu prepared from ozone treated-soybean.

• 한국물환경학회지
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• 제20권2호
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• pp.126-131
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• 2004

This research sought to compare chlorine, chlorine dioxide and ozone as chemical disinfectants of drinking water, with inactivation of total coliform as the indicator. The inactivation of total coliform was tested against several variables, including the dose of disinfectant, contact time, pH, temperature and DOC. A series of batch processes were performed on water samples taken from the outlet of a settling basin in a conventional surface water treatment system that is provided with the raw water drawn from the mid-stream of the Han River. Injection of 1 mg/L of chlorine, chlorine dioxide and ozone resulted in nearly 2.4, 3.0 and 3.9 log inactivation, respectively, of total coliform at 5 min. To achieve 99.9 % the inactivation, the disinfectants were required in concentrations of 1.70, 1.00 and 0.60 mg/L for chlorine, chlorine dioxide and ozone, respectively. Bactericidal effects generally decreased as pH increased in the range of pH 6 to 9. The influence of pH change on the killing effect of chlorine dioxide was not strong, but that on ozone and free chlorine was sensitive. The activation energies of chlorine, chlorine dioxide and ozone were 36,053, 29,822 and 24,906 J/mol for coliforms with inactivation effects being shown in the lowest orders of these.

• Korean Chemical Engineering Research
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• 제44권6호
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• pp.644-649
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• 2006

본 연구에서는 다양한 조건에서 기체상태의 오존처리된 활성탄소를 이용하여 수용액 상태에서의 Cr(VI)의 흡착특성에 대하여 고찰하였다. 오존처리된 활성탄소의 표면특성의 변화는 pH, 산도-염기도, FT-IR을 이용하였으며, $N_2$/77K 등온 흡착특성은 BET식, Boer의 t-plot, 그리고 Horvath-Kawazoe의 slit pore model을 이용하여 확인하였다. 또한, 총 Cr의 흡착량은 ICP-AES를 이용하여 확인하였다. 실험 결과, 오존처리는 활성탄소의 표면에 산소를 함유한 극성 관능기를 증가시켰으며, 이로 표면산도 또한 증가되었다. 한편, 오존처리의 영향으로 보이는 활성탄소의 비표면적과 미세기공 부피의 감소가 관찰되었지만, 활성탄소의 총 Cr 흡착량은 오존처리 시간이 증가할수록 비례적으로 증가하였다. 이는 활성탄소의 Cr 흡착특성이 비표면적보다 상대적으로 표면에 형성된 극성 관능기의 영향을 크게 받는 것으로 판단된다.

• 한국토양비료학회지
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• 제47권5호
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• pp.362-367
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• 2014

This study was performed to test the applicability of the ozone/hydroxy radical reaction system, which applied advanced oxidation processes, to remove total petroleum hydrocarbon (TPH) from the fine soil in washing water of the soil washing process. Removal efficiency was tested on 40 L of washing water in a pilot reaction tank. Fine soil contaminated with $800mg\;kg^{-1}$ TPH was prepared at 5% and 10% suspended solids. Testing conditions included ozone/hydroxy radical flow rates of 40, 80, and $120L\;min^{-1}$, and processing time of 2 to 12 hours. The removal efficiency of petroleum hydrocarbon from water waster by ozone/hydroxy radical was increased with higher flow rates and lower percentages of suspended solids. Optimal efficiency was achieved at $80L\;min^{-1}$ flow rate for 4 hours for the 5% suspended solids, and $120L\;min^{-1}$ for 6 hours for the 10% suspended solids. These results verified the efficiency of hydroxy radical in removing TPH and the applicability of the ozone/hydroxy radical reaction system in the field.

• 한국산업융합학회 논문집
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• 제10권1호
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• pp.15-20
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• 2007

The aim of this study is to measure the removal characteristics of organic matter and bacteria with the use of ozone to reduce the problems caused by bacteria and organic matter which appear in sea-water is summer season. When the total input of ozone was $1.4mg/{\ell}O_3$, the removal rate of bacteria and E-coli from sea-water proved to be 100%. With the same input of ozone, on the other hand, the removal rate of COD turned to be relatively low, 50%, which was to the fact that sea-water consists of salt matter which is a kind of COD matter. This result supports the idea that we can keep using ozone steadily in the future to remove organic matters and bacteria from sea-water because ozone destructs relatively less salt matter in sea-water. Also, the treatment effect rate of SS, turbidity and organic matters such as $NH_3$-N, $NO_3$-N etc, was very high. As a result, we assume that the treatment of organic matter in sea-water with ozone is very effective

• Ocean and Polar Research
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• 제26권3호
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• pp.439-451
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• 2004

Total solar irradiance (750), total UV irradiunce (TUV) and erythemal UV irradiance (EUV) measured at King Sejong station $(62.22^{\circ}S,\;58.78^{\circ}W)$ in west Antarctica have been used together with total ozone, cloud amount and snow cover to examine the effects of ozone, cloud and snow surface on these surface solar inadiunce over the period of 1998-2003. The data of three solar components for each scan were grouped by cloud amount, n in oktas $(0{\leq}n<3,\;3{\leq}n<4,\;4{\leq}n<5,\;5{\leq}n<6,\;6{\leq}n<7\;and\;7{\leq}n<8)$ and plotted against solar zenith angle (SZA) over the range of $45^{\circ}\;to\;75^{\circ}$. The radiation amplification factor (RAE) is used to quantify ozone effect on EUV. RAF of EUV decreases from 1.51 to 0.94 under clear skies but increases from 0.94 to 1.85 under cloudy skies as SZA increases, and decreases from 1.51 to 1.01 as cloud amount increases. The effects of cloud amount and snow surface on EUV are estimated as a function of SZA and cloud amount after normalization of the data to the reference total ozone of 300 DU. In order to analyse the transmission of solar radiation by cloud, regression analyses have been performed for the maximum values of solar irradiance on clear sky conditions $(0{\leq}n<3)$ and the mean values on cloudy conditions, respectively. The maximum regression values for the clear sky cases were taken to represent minimum aerosol conditions fur the site and thus appropriate for use as a normalization (reference) factor for the other regressions. The overall features for the transmission of the three solar components show a relatively high values around SZAs of $55^{\circ}\;and\;60^{\circ}$ under all sky conditions and cloud amounts $4{\leq}n<5$ and $5{\leq}n<6$. The transmission is, in general, the largest in TUV and the smallest in EUV among the three components of the solar irradiance. If the ground is covered with snow on partly cloudy days $(6{\leq}n<7)$, EUV increases by 20 to 26% compared to snow-free surface around SZA $60^{\circ}-65^{\circ}$, due to multiple reflections and scattering between the surface and the clouds. The relative difference between snow surface and snow-free surface slowly increases from 9% to 20% as total ozone increases from 100 DU to 400 DU under partly cloud conditions $(3{\leq}n<6)$ at SZA $60^{\circ}$. The snow effects on TUV and TSO are relatively high with 32% and 34%, respectively, under clear sky conditions, while the effects changes to 36% and 20% for TUV and TSO, respectively, as cloud amount increases.

• 대한환경공학회지
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• 제22권10호
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• pp.1825-1832
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• 2000

유류화합물(디젤)로 오염된 불포화층 토양에 대한 현장오존복원공정의 기초연구로, 토양조건에 따른 오존의 이동과 분해, 디젤과의 반응경향을 조사하였다. 건조상태에서 유기물을 제거한 모래와 glass beads 충진컬럼에서 기상 오존의 분해를 조사한 결과 일차반응으로 가정시 반응 속도상수값(k)이 각각 $9.9{\times}10^{-3}s{^{-1}}$와 $4.3{\times}10^{-4}s{^{-1}}$로 나타나 모래의 경우 철 (Fe), 망간(Mn) 성분 등의 촉매작용으로 25배 가량 반감기가 짧은 것을 확인할 수 있었다. 디젤로 오염시킨 현장 토양과 모래를 컬럼에 충진하여 동일조건하에서 오존주입시 토양입자의 크기와 유 무기물의 함량 차에 의한 오존이동상에 지체효과 및 소모량의 차이를 관찰하였고, 50mL/min의 유속에서 공기만을 주입시 DRO(diesel range organic) 기준 초기 디젤총량($800{\pm}50mg/kg$)의 30%가 제거된데 비해 오존을 6mg/min으로 16시간 주입한 결과 각각 80% 이상이 제거되었다. 오존주입시간에 따라 컬럼의 유출 입부에 잔류하는 TPH(total petroleum hydrocarbon)와 DRO 중 aliphatic계열 8개 물질들의 농도를 비교/분석한 결과, 낮은 탄소수 물질들로의 전환과정을 거쳐 유체의 흐름에 따라 컬럼 밖으로 이동됨을 확인하였고, 토양내 수분함량은 오염 토양복원에 오존을 적용시 중요한 인자임을 확인하였다.

• Asian Journal of Atmospheric Environment
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• 제9권4호
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• pp.237-246
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• 2015

We conducted intensive observations of ozone, CO, $NO_x$ (=NO and $NO_2$), $NO_y$ (total odd nitrogen species including particulate nitrate) and total nitrate (the sum of gaseous $HNO_3$ and particulate nitrate) at Cape Hedo, Okinawa, Japan, from 19 March to 3 April, 2009, to investigate ozone production during long-range transport from the Asian continent. Ozone production efficiency (OPE) was used to evaluate photochemical ozone production. OPE is defined as the number of molecules of ozone produced photochemically during the lifetime of a $NO_x$ molecule. OPE is calculated by the ratio of the concentration increase of ozone to that of $NO_z$ ($=NO_y-NO_x$). Average OPE during observation was estimated to be $12.6{\pm}0.5$, but concentrations of ozone increased nonlinearly with those of $NO_z$. This non-linearity suggests that OPE depends on air mass origin and $NO_z$ concentrations. There were very different values of OPE for the same air mass origin, so that only the air mass origin alone does not control OPE. OPE was low when $NO_z$ concentration was high. We examined the correlation between $NO_z$ and $CO/NO_y$ ratios, which we used instead of the ratio of non-methane hydrocarbons (NMHCs) to $NO_x$. The $CO/NO_y$ ratios decreased with increasing $NO_z$ concentrations. These results indicate that competition reactions of OH with NMHCs and $NO_2$ are the rate determining steps of photochemical ozone production during long-range transport from the Asian continent to Cape Hedo, for high concentrations of nitrogen oxides.

• 한국대기환경학회지
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• 제11권1호
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• pp.85-93
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• 1995

Measurements of ground level ozone concentrations were made in a rural area of Chongwon (Choongbook Province) from June 1993 to July 1994. High values frequently exceeding 100 ppb (ambient air qualyty standard of Korea) were recorded. High ozone concentrations in the boundary layer were primarily correlated with the several meteorological parameters in warm seasons: pressure, radiation, temperature, precipitation and wind velocity. The annual average concentration of ozone at Chongwon was 17ppb, and this value was relatively higher than those for other cities in Korea. O$\_$3/ concentrations were observed to increase when the ridge of a surface anticyclone was passing over the region, and maximum values(.geq.100 ppb) were observed on the rear sides of high pressure centers and in the warm sectors of cyclones(well head of cold fronts). The ozone concentrations had a negative correlation with the concentration of primary pollutants(e.g., total hydrocarbons).