• Nuclear Engineering and Technology
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• 제22권1호
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• pp.1-11
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• 1990

중수는 중수형 원자로의 감속재 및 냉각재로 사용되고 있으며 그 가격이 고가이기 때문에 일단 계통내에서 사용된 후 농도가 낮아진 저등급 중수는 중수승급기를 통해 99.8% 이상으로 농축 재생되어 중수로로 재주입되고 있다. 본 연구에서는 중수승급기의 공정을 면밀히 검토하였고 정상상태의 중수증류공정의 해석을 위하여 이론적인 모델을 제시하였으며 변수들간의 관계식을 설정하였다. 그리고 이 비선형 관계식을 단계적으로 처리하는 알고리즘의 전산 프로그램 UPGR을 개발하였다. 전산코드의 결과는 실제 운전 데이타와 잘 일치하였다. 월성 1호기에서 이를 이용한 운전지침의 제시, 운전효율의 평가, 성능평가 및 성능관리를 수행함으로써 중수승급기의 효율적인 운전에 기여하고 있다.

• 한국토양비료학회지
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• 제49권1호
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• pp.81-86
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• 2016

Heavy metal pollution in agricultural fields at the abandoned metal mines has been serious problems in Korea. In order to manage heavy metal pollution in surface water and soil, numerous remediation strategies have been established. Therefore, main purpose of this research was to examine feasibility of ecological toxicity assessment for establishing management strategy in heavy metal polluted agricultural fields. Heavy metal concentration in surface water and soil was monitored along with ecotoxicity experiment with Daphnia magna and Eisenia fetida. Result showed that high toxicity was observed in heavily polluted agricultural field with heavy metals. In case of mortality of Daphnia magna (85%) and Eisenia fetida (6.7%), the highest ratio was observed when heavy metal concentration in surface and soil was high. Calculated ecotoxicity index (EI) ranged 0.06-0.30 and the highest EI was observed in heavily polluted sites among 5 abandoned metal mines. Overall, ecological toxicity assessment is necessary to evaluate heavy metal pollution in agricultural fields near at the abandoned metal mines along with chemical concentration analysis.

• 한국식품위생안전성학회지
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• 제14권3호
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• pp.305-318
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• 1999

식품의 안전성을 확보하고 건강상의 위험을 방지하기 위하여 또 수산 어패류 중의 중금속 분포상태를 파악하기 위해 국내에서 유통되고 있는 민물어류 11종 166건, 패류 14종 153건 등 총 319건을 대상으로 Pb, Hg, Cd, Cr, Fe, Mn, Zn, Cu 의 8개 금속을 A.A.S. 와 Mercury Analyzer로 측정하여 다음과 같은 결과를 얻었다. 1. 민물어류에서의 중금속 평균함량은 Pb 0.075, Hg 0-.053, Cd 0.002, Cr 0.135, Fe 8.695, Mn 1.078, Sn 9.491, Cu 0.548 mg/kg으로 나타났다. 패류에서의 중금속 평균 함량은 Pb 0.059, Hg 0.007, Cd 0.146, Cr 0.147, Fe 40.808, Mn 7,738, Zn 13.943, Cu 2.731 mg/kg으로 조사되어, Cd , Fe, Mn, Cu 등이 민물어류에 비해 높은 것으로 나타났다. ()P<0.001). 2. 중금속 함량은 산지에 따라 유의한 차이가 있는 것으로 나타났다. 민물어류의 경우 Mn 과 Zn 함량이 지역간의 유의성을 나타냈다. (p<0.001). 패류의 경우는 Fe, Mn, Zn 함량이 지역간의 유의성을 나타내었다. (p<0.01). 3. 계절에 따라 중금속 함량에도 차이가 있는 것으로 나타났다. (p<0.05). 민물어류에서는 겨울철의 Pb, Zn, Cr, Cu 함량이 높은 것으로 나타났고, 패류에서는 겨울철에 Pb, Zn 함량이 높은 것으로 나타났다. 4. 조사된 결과를 종합 고찰하면 우리나라 서식하고 있는 어패류에 함유된 중금속 함량은 유해농도이하이며 , Fe, Mn, Zn 등 미량 영양염류 함량은 비교적 높은 것으로 나타났다.

• 한국물환경학회지
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• 제24권5호
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• pp.533-536
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• 2008

Korean water quality guidelines for agricultural were derived to protect agricultural water uses according to the Canadian methodology. The adverse effect of heavy metals in agricultural water was of concern due to its persistence, bioaccumulation and ecotoxicity to crop plants. The ecotoxicity data of cadmium, copper, lead, and zinc were collected for the crops grown in Korea, and used to estimate the species maximum acceptable toxicant concentration (SMATC), which corresponds to the water quality guideline. Values of irrigation per year and soil bulk density were revised to reflect the Korean situation. The estimated guideline values for cadmium, copper, lead, and zinc were 0.01, 0.5, 0.1, and 1.0 mg/L, respectively. These values are in agreement with the agricultural water quality guidelines of foreign countries and current Korean water quality standard for the protection of public health. Current water quality standards in agricultural uses were for management of public water resource, and was not prepared to protect crop plants from contaminants. The results of this study will be a basis for the designation of Korean water quality guidelines for the protection of agricultural water uses in the future.

• 환경위생공학
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• 제19권2호
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• pp.45-50
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• 2004

To investigate the epilithic diatom community and water quality of the Osan stream, water samples were collected from the eight stations from April to September 2003. Sampling was two times before and after heavy rain. Total 52 diatom were identified and divided into 12 saproxenosus taxa, 6 saprophilous taxa and 34 indifferent taxa, respectively. The DAIpo values higher after heavy rain than before that. According to tolerance degree to the organic water pollution, all sampling stations ranged from $\alpha$-oligosaprobic to $\alpha$-mesosaprobic. Thus, the result indicates that the water quality of Osan stream is gradually improved by heavy rain.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.1-8
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• 2005

Baiyangdian Lake, the largest freshwater lake in North China, is known as 'Pearl of North China' and 'kidney of North China' fur its abundant products and multiple ecological services. However, from the 1970s, due to the ever-increasing discharge of polluted water from upstream rivers, it has been severely polluted. Sediment Investigation and analysis were conducted on contents of heavy metal (Cu, Zn, Cd and Pb) from Baiyangdian Lake in June 2004. Results showed that pollution situation at downriver regions are more serious than that of upstream regions. The seriously polluted spots are access of Fuhe River, original wastewater reservoir of Tanghe River, densely populated Chunshui Village and Wangjiazhai Village. By using method of the potential ecological risk assessment, the heavy metal evaluation of polluted sediment has been conducted. The results showed that the contents of Cd and Pb were very high in sediment of Baiyangdian Lake. There were extremely stronger ecological risk for Cd and slight- medium ecological risk for Pd. According to the current situation of Baiyangdian Lake, countermeasures and suggestions have been put forward.

• 한국농공학회논문집
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• 제48권1호
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• pp.3-10
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• 2006

The chemical fractions of heavy metals were investigated in the soils of reclaimed and natural tidelands of southwest coastal area of Korea. The distribution pattern of each heavy metal in different fractions was in the order: 1) Cu : organic bound > organic complex > residual > exchangeable = water soluble. 2) Cr : residual > organic bound > organic complex > water soluble > exchangeable. 3) Pb : organic bound > residual > organic complex > water soluble > exchangeable. 4) Cd residual > organic bound > organic complex > water soluble = exchangeable. 5) Zn : organic bound > residual > organic complex > water soluble > exchangeable. The content of residual Zn showed positive correlation with organic matter content but organic bound Zn showed negative correlation with CEC. The content of residual and exchangeable Cd showed highly positive correlation with organic matter content but residual, organic bound, and exchangeable Cd showed negative correlations with CEC. Water soluble Pb showed positive correlation with CEC but organic bound Pb showed negative correlation with CEC.

• Membrane and Water Treatment
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• 제11권2호
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• pp.167-172
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• 2020

The effectiveness of in situ sediment capping as a technique for heavy metal risk mitigation in Hyeongsan River estuary, South Korea was studied. Sites in the estuary were found previously to show moderate to high levels of contamination of mercury, methylmercury and other heavy metals. A 400 m x 50 m section of the river was selected for a thin layer capping demonstration, where the total area was divided into 4 sections capped with different combinations of capping materials (zeolite, AC/zeolite, AC/sand, zeolite/sand). Pore water concentrations in the different sites were studied using diffusive gradient in thin film (DGT) probes. All capping amendments showed reduction in the pore water concentration of the different heavy metals with top 5 cm showing %reduction greater than 90% for some heavy metals. The relative maxima for the different metals were found to be translated to lower depths with addition of the caps. For two-layered cap with AC, order of placement should be considered since AC can easily be displaced due to its relatively low density. Investigation of methylmercury (MeHg) in the site showed that MeHg and %MeHg in pore water corresponds well with maxima for sulfide, Fe and Mn suggesting mercury methylation as probably coupled with sulfate, Fe and Mn reduction in sediments. Our results showed that thin-layer capping of active sorbents AC and zeolite, in combination with passive sand caps, are potential remediation strategy for sediments contaminated with heavy metals.

• 한국패류학회지
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• 제7권1호
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• pp.87-93
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• 1991

Heavy metals, Cd, Pb, Cu, Mn, Zn in water, sediments and molluscs along coast line of Hwang-hae(Yellow sea)were examined. The collection sited werer close to esturies of Kum-gang and Mankyeong-Gang, where industries have been rapidly developed along the rivers in recent in recent years. Cadmium and lead in water were 0.32ppb and 4.12 ppb respectively on Kun-san, but not on Jang hang. In general, Cd, Pb, Mn and Zn were detected in the regions of mouth paart of rivers, whereas none or far less amounts were detected from Puan, a control site: 20km apart from estury of Mangyeong Gang. Cd and Pb in sediments of Kunsan were 0.46ppm and 9.31ppm respectively and 0.36ppm and 0.41ppm in Shim-po, but far less amounts in Byeon san.Heavy metals in shellfish were: Cd 0.78ppm and Pb 0.42ppm in Kun san, 0.74ppm and 0.74ppm in Shim po, and showed higher values compare to other sites. In general, heavy metal contamination of sedimets and molluscs in each are were correlated with grade of the water pollution due to heavy metals.

• Toxicological Research
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• 제24권4호
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• pp.297-305
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• 2008

This study was carried out to measure the concentration of heavy metals (Pb, Mn, Cr, Cd, Ni, Zn, and Cu) in water and Bolti fish (Tilapia nilotica) samples collected from Rasheed branch of River Nile, north of El-Giza Governorate, Egypt by atomic absorption spectrophotometry. The investigated districts through which the branch passes include El-Manashi, Gezzaya, El Katta, Abo Ghaleb and Wardan. Based on WHO and FAO safety reference standards, the results of the current study showed that water and fish tissues were found to contain heavy metals at significantly variable concentration levels among the investigated districts. They were polluted with respect to all the metals tested at Gezzaya district. However, the levels of analyzed metals in water and fish tissues were found lower than legal limits in other districts. The heavy metals showed differential bioaccumulation in fish tissues of the different districts as the accumulation pattern (as total heavy metal residues) was district dependant as follow: Gezzaya > Wardan > El Katta > Abo Ghaleb > El Manashi.