• 한국환경과학회지
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• 제15권5호
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• pp.405-415
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• 2006

Sixteen soil samples around six areas (residental area, traffic area, power plant area, incineration area and factory area) where the stationary and mobile sources of polycyclic aromatic hydrocarbons (PAHs) are estimated to be emitted in Jeju City, were collected during Feburuary to March, 2004, and analyzed for 16 PAHs recommended by US EPA as primary pollutants to investigate their distribution characteristics. The concentrations of total PAHs (t-PAHs) and total carcinogenic PAHs $(t-PAH_{CARC})$ in soils of Jeju City were in the range of $21.7\sim264.2ng/g$ on a dry weight basis with a mean value of 87.2 ng/g and $6.3\sim118.0ng/g$ with a mean value of 33.4 ng/g, respectively. The concentrations of t-PAHs were low in comparison with those in soils of other domestic and foreign countries. The mean concentrations of t-PAHs and $(t-PAH_{CARC})$ with area decreased in the following sequences: traffic area> incineration area > factory area > power generation area > harbor area enli residental area. The correlation between t-PAHs and $(t-PAH_{CARC})$ were very high $(\gamma^2=0.9701)$, indicating that $(t-PAH_{CARC})$ concentration increases in proportion with t-PAHs. Comparing the distribution ratio of ring PAHs with area among 16 PAHs, it decreased in the order of 4-ring > 5-ring > 6-ring > 3-ring > 2-ring in all the areas except for harbor area. whitens for harbor area it was similar among 3-, 4- and 5-ring with high value. Low and no correlations between t-PAHs and soil compositions (organic matter content and particle size distribution) were observed, which is considered to be caused by the complex factors, such as the loading and characteristics of PAHs and diverse soil environment change, etc. From the examination of the three PAH origin indices, such as LMW/HMW (low molecular weight $2\sim3$ ring PAHs over high molecular weight $4\sim6$ ring PAHs), phenanthrene/anthracene ratio and fluoranthene/pyrene ratio, it can be concluded that the soil PAH contaminations were ascribed to strong pyrogenic origin in ail areas except for harbor area and to both pyrogenic and petrogenic origins.

• 한국환경과학회지
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• 제24권11호
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• pp.1343-1362
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• 2015

As a result of analysis based on the observed data for BOD, COD and TOC in order to manage non-biodegradable organics in the Geumho River, COD/BOD ratio was analyzed as the occupying predominance proportion. In this study, the classification(changes in water quality measurement : increase, equal, decrease) and measurement of BOD and COD were analyzed for trends over the past 10 years from 2005 to 2014 in the Geumho River. The Geumho River is expected to need non-biodegradable organics management because BOD was found to be reduced 61.1% and COD was found to be increased 50%. As a result of the analysis of land use, the Geumho-A is a unit watershed area of $921.13km^2$, which is the most common area that is occupied by forests. The Geumho-B is a unit watershed area of $436.8km^2$, which is the area that is highest occupied by agriculture and grass of 24.84%. The Geumho-C is a unit watershed area of $704.56km^2$ accounted for 40.29% of the entire watershed, which is the area that is occupied by urban of 15.12%. Load of non-biodegradable organics, which is not easy biodegradable according to the discharge, appeared to be increased because flow coefficient of COD and TOC at the Geumho-B were estimated larger than 1 value. The management of non-point sources of agricultural land is required because the Geumho-B watershed area occupied by the high proportion of agriculture and field. In this segment it showed to increase the organics that biodegradation is difficult because the ratio of BOD and TOC was decreased rapidly from GR7 to GR8. Thus, countermeasures will be required for this.

• 한국환경농학회지
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• 제26권1호
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• pp.25-35
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• 2007

인공습지나 수변녹지 및 완충 저류지와 같은 수질정화시설을 조성하는데 이용할 수 있는 수생식물을 선발하고자 낙동강 하류에 자생하는 수생식물과 외래 수생식물, 습생작물을 대상으로 부영양화 성분(T-N, T-P) 및 EC 관련 무기성분에 대한 정화능력을 검정하였다. 수생식물의 생육기간 동안 $225{\sim}444\;L\;m^{-2}$ 범위의 생활오폐수를 사용하였으며, 건물생산량이 많았던 벼와 부들, 줄, 비자루국화, 율무, 털물참새피 등이 350 L $m^{-2}$ 이상으로 가장 많은 생활하수를 소모하였다. 질소와 인의 체내흡수량과 실제 정화능력(정화효율 및 정화량) 및 수확 후 토양을 분석한 결과, 초장이 크면서 건물량도 많았던 벼, 비자루국화, 부들, 율무, 털물참새피, 줄 등이 부영양화성분에 대한 우수 정화식물로 선발되었다. 무기성분 중 K에 대한 정화력은 부영양화성분의 우수 정화식물로 선발된 수생식물과 더불어 물상추와 부레옥잠이 높은 결과를 보였다. EC와 관련이 높은 Ca와 Na, Cl에 대한 정화효과가 우수한 수생식물로는 물상추와 부레옥잠, 털물참새피가 선발되었으며, 특히 털물참새피는 $SO_4$에 대한 정화효과도 뛰어났다.

• 상하수도학회지
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• 제18권3호
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• pp.392-400
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• 2004

This research uses the $TiO_2$/UV process to verify the most suitable condition and possibility to dispose dyeing wastewater that contains pigment and a large amount of pollutants. For this, this research has enforced experiments that compare photo adsorption, photolysis, and photo catalyst oxidation reaction, and also evaluated and analyzed the change of pH and $TiO_2$ dosage, irradiation rates of ultraviolet rays and the dosage change and injection method of $H_2O_2$. According to the results of the dyeing wastewater experiment of storehouse catalyst that uses the new form of $TiO_2$, the photo catalyst oxidation reaction proved to be more effective than photo adsorption and photolysis; 35%, 21% in the case of $TCOD_{cr}$ and 39%, 28% in the case of chromaticity. Taking into consideration the reaction time, amount of photo catalyst reaction and irradiation amount of ultraviolet rays, the decomposition efficiency of pH change proved to be most effective at pH 4. On the whole, the acidity area proved to be effective in dyeing water exclusion than neutral and alkalinity areas. Having evaluated the influence of $TiO_2$ dosage, not only does the decomposition efficiency continuously improve as the $TiO_2$ dosage increases but the shielding effect does not occur also when the $TiO_2$ is at a fixed state. The influence of ultraviolet irradiation amount concluded in the result that as the ultraviolet irradiation amount increases the decomposition efficiency continually increased, but in the case of chromaticity when the irradiation amount was higher than 37.8mW/cm2 the removal efficiency is slowed remarkably. The influence of $H_2O_2$ dosage evaluation reached the results that although the decomposition efficiency increases with the increase of $H_2O_2$ dosage, when above 150mg (total dosage: 1200mg) $H_2O_2$ consumes OH radical itself and reduces the decomposition efficiency. Also in the case of the $H_2O_2$ injection method rather than injecting in the whole amount of $H_2O_2$ (1200mg) needed at the beginning all at once, injecting divided quantities of $H_2O_2$ whenever the electric current density falls below 10mgfl reduces the wases of OH radical due to an excess of $H_2O_2$ and in tum heightens the decomposition efficiency.

• 과학기술학연구
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• 제10권1호
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• pp.107-152
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• 2010

이 논문은 아토피 질환에 대한 '한국적'인 이해와 대응을 낳은 역사적 과정을 살펴본다. 유전적 소인이 있는 특이면역성 질환 아토피는 외국의 경우에 '환경병'으로 인식되는 우가 드물다. 하지만 한국에서 아토피는 '환경호르몬' 등의 위험요소들과 결부되며 표적 환경병의 지위를 갖고 있다. 아토피에 대한 이러한 이해는 사전예방원칙과, 매체중심이 아닌 수용자중심의 환경오염 관리라는 전향적 원칙을 내세운 2008년의 환경보건법 탄생에 중요한 역할을 했다. 논문은 이 규제과정에 있어서 대중의 지식적 정치적 활동의 역할을 살펴본다. '아토피 = 환경병'으로 아토피를 이해하는 데 있어 가장 중요한 역할을 한 것은 아토피 아이들을 둔 아토피 엄마들이다. 이들은 의학과 독성학 등 과학계의 성과는 물론 본의 '아토피 아이, 지구의 아이'와 같은 환자조직의 활동경험과 성과를 이용, 대중적 호소력을 발휘한 '아토피 이론'을 제시했다. 이들은 과학적 불확실성을 전용하는 편, 한의학계, 생협, 민노당 등과도 지식 정치적 연대를 형성함으로써 환경보건법이라는 성과를 내게 된다. 이 논문은 이 과정을 검토함에 있어 '대중'이라는 주체가 성되어가는 역사성과 사회적 이슈 형성의 문화적 맥락에 관심을 돌린다. 이러한 연구는 위험규제나 정책연구 등에 역사적 역동성에 대한 논의의 단초를 만들 수 있다.

• 한국세라믹학회지
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• 제45권12호
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• pp.839-844
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• 2008

$TiO_2$ is an environment-friendly semiconducting material, and it has photocatalytic and hydrophilic effect. There are a lot of reports on the photocatalytic characteristics of $TiO_2$, such as organic pollutants resolving, anti-bacterial, and self-purification material. In this paper, $TiO_2$ micron-sized powders were deposited on the glass by room temperature powder spray in vacuum process, so called aerosol deposition (AD), and nano-grained $TiO_2$ photocatalytic thin films were fabricated. The thickness of the films were controlled by changing the number of deposition cycle. Morphologies and characteristics of the AD-$TiO_2$ thin films were examined by SEM, TEM, XRD, and UV-Visible Spectrophotometer. As the thickness of $TiO_2$ films increased, surface roughness increased. By this increment, the reaction area between film and pollutant was enlarged, resulting in better photocatalytic property.

• 한국대기환경학회지
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• 제33권2호
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• pp.87-96
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• 2017

In this study, 4 gases containing typical chlorinated volatile organic compounds (VOCs) were treated by ultraviolet (UV) irradiation. The typical chlorinated VOCs are dichloromethane (DCM), trichloromethane (TCM), carbon tetrachloride (CTC) and trichloroethylene (TCE). The removal efficiency (RE) and the products of chlorinated VOCs by UV irradiation are investigated. At this time, 2 types of background gas (air and nitrogen) were used to figure out the RE by photooxidation and photolysis. The specification of UV-lamp used in this study was low-pressure mercury lamp emitting wavelength of 185~254 nm. The experimental conditions were set as initial VOC concentration of $180{\pm}10ppm$, empty bed retention time (EBRT) of 53 s, temperature of $23{\pm}2^{\circ}C$ and relative humidity of $65{\pm}5%$. In the photolysis condition with nitrogen ($N_2$) as background gas, the averaged RE of the 4 types of chlorinated VOCs was about 24% higher than that with photooxidation; and the REs of VOCs except CTC were confirmed as >99%. The composition of off-gases after UV photooxidation in air was investigated and several intermediates from DCM, TCM and TCE were detected by GC/MS. Among them, phosgene which is a toxics was detected as an intermediate of TCM. In addition, the concentration of carbon dioxide ($CO_2$) in the off-gases was measured to calculate the mineralization rate (MR). With the photooxidation, TCE showed the highest RE (>99%) while MR was the lowest (17%); and the MR of DCM was the highest (86%). In addition, particulate matters (PM) in the off-gases was also detected and high concentrated $PM_{10}$ ($21,580{\mu}g{\cdot}m^{-3}$) and $PM_{2.5}$ ($6,346{\mu}g{\cdot}m^{-3}$) were detected in TCE off-gas. More than 99% of the chlorinated VOCs could be removed using UV254-185 nm lamp, while it is necessary to conduct further studies on the production and treatment of secondary pollutants.

• 한국수자원학회논문집
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• 제47권12호
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• pp.1135-1143
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• 2014

본 연구에서는 사상성 조류로 구성된 수질정화시설의 수질정화효율을 평가하고자 충남 서산시 음암면에 소재한 성암저수지 유입하천 홍수부지에 test-bed를 설치하고 유입하천수를 대상으로 현장적용실험을 실시하였다. 수질항목별로 정화효율을 평가한 결과, SS 80.9%, COD 74.6%, T-N 76.8%, T-P 84.4%, DTN 93.8%, DTP 98.3%의 제거효율을 보였다. 수온에 따른 정화효율은 수온이 약 $20^{\circ}C$로 유지되어 수질정화효율에 미치는 영향은 없는 것으로 나타났다. 수리학적 체류시간(HRT)은 SS 및 TP 처리효율과 유의한 상관성이 있는 것으로 나타났고, 체류시간을 5일로 했을 때 SS, TP 처리효율이 좋은 것으로 나타났다. 유입수의 COD/TN에 따른 처리효율은 TN, TP 모두 C/N비가 낮을수록 증가하였고, 유입수의 COD/TP에 따른 처리효율도 C/P비가 낮을수록 TN, TP 모두 처리효율이 증가하는 것으로 나타났다.

• 한국습지학회지
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• 제19권1호
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• pp.69-79
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• 2017

국내의 상수원으로 사용하는 수질보호구역은 주로 농촌지역인 경우가 많다. 농촌지역의 경우 인구수 및 인구밀도가 높지 않아 하수도 시스템 보급이 열악하여 상수원 관리를 위해서는 농촌지역의 하수처리에 관리가 필요하다. 본 연구에서는 농촌지역에 위치한 마을하수도 4개소와 하수처리장의 운전결과를 분석하였다. 마을하수도보다 하수처리장에서 고농도의 오염물질이 유입되었으며, 방류수 수질 기준은 모두 만족하는 것으로 나타났다. 하지만 마을하수도의 방류수의 오염물질 농도가 하수처리장보다 더 높은 것으로 조사되었다. 처리 효율에서는 median 값으로 유기물(BOD, COD)의 경우 약 5%정도, 영양염류(T-N, T-P)의 경우 최대 30%정도 높게 검출되었다. 또한 오염물질 처리효율에 MLSS, DO 및 체류시간과 같은 생물반응조 운전 인자가 미치는 영향에 대해 분석하였다. 그 결과 운전 조건에 따라 오염물질 처리효율이 변하는 것으로 나타났다. 따라서 농촌지역에서 하수 관리를 위해서는 생물 반응조 운전 조건 등의 유지관리에 주의를 기울여야 한다.

• Environmental Analysis Health and Toxicology
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• 제10권1_2호
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• pp.1-14
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• 1995

The purpose of this research is to assess the health risk of pollutants in drinking water and recommend the guidelines and management plans for maintaining good quality of drinking water. This study has been funded as a national project for three years from 1992 to 1995. This study(the second year, 1993-1994) was conducted to monitor 32 species of carcinogenic chemicals such as volatile organic compounds(VOCs), polynuclear aromatic hydrocarbons(PAHs), pesticides and heavy metals of drinking water at some area in six cities of Korea, and evaluate health risk due to these chemicals through four main steps of risk assessment in drinking water. In hazard identification, 32 species of carcinogenic chemicals were identified by the US EPA classification system. In the step of exposure assessment, sampling of raw, treated and tap water from the public water supply system had been conducted from 1993 to 1994, and 32 chemicals were analyzed. In dose-response assessment, cancer potencies, unit risk estimates and virtually safe doses of carcinogens were obtained by TOX-RISK (Version 3.1). In risk characterization of detected chemicals, health risk due to carcinogens such as vinyl chloride, carbon tetrachloride, dichloromethane, 1, 2-dichloromethane, chloroform, benzene and arsenic of tap water in several cities exceeded 10$^{-5}$ level. We suggest that non-regulated chemicals which exceed 10$^{-5}$ excess cancer risk level, such as vinyl chloride, carbon tetrachloride and 1, 2-dichloroethane, should be monitored periodically and be regulated by the Drinking Water Management Act, and database for exposure parameter of our own situation should be established.