• 수산경영론집
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• 제53권2호
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• pp.58-72
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• 2022

Fishery products play an important role in Korean food culture, and awareness of the safety of fishery products is increasing in the seafood market. Against this backdrop, Japan has announced a plan to release radioactive water to the sea from 2023. In the case of Korea, it is adjacent to the area to be discharged, so there are concerns about securing the safety of marine products. Therefore, it is necessary to analyze the change in perception and impact of marine product consumers due to the discharge of contaminated water and to study appropriate countermeasures when discharging contaminated water from nuclear power plants. In this study, the current status of radioactive contaminated water discharge in Japan was summarized, and a survey was conducted on the change in the consumption perception of marine products according to the discharge of contaminated water to analyze the factors affecting the consumption change of domestic consumers. According to the survey, 85.3% of the respondents said that it will affect the purchase of domestic marine products if Japan starts discharging contaminated water from nuclear power plants. Moreover, 85.5% of the respondents said it will affect the purchase of imported marine products.

• 한국지하수토양환경학회지:지하수토양환경
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• 제16권3호
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• pp.10-16
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• 2011

The experimental studies for remediation of diesel contaminated soils were performed using subcritical water in laboratory scale. Contaminated soils from industrial area and artificially contaminated soils were utilized for soil remediation. Experimental system was composed for subcritical water to flow upward through the soil packed column for extracting contaminants. 10 g of contaminated soil was packed into the column and water flow rate was 2 mL/min. To evaluate the effects of temperature, pressure and treatment time on the removal efficiency, temperature was changed from 100$^{\circ}C$ to 350$^{\circ}C$, pressure from 50 bar to 220 bar and treatment time at the predetermined temperature from 0 min to 120 min. The purification efficiency increased as temperature increased. However, the effect of pressure and treatment time was low. Temperature 250$^{\circ}C$, pressure 50 bar and treatment time 30 min were selected for optimal operating condition for this study.

• 한국물환경학회지
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• 제27권6호
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• pp.862-867
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• 2011

Pozzolanic-based stabilization/solidification (S/S) is an effective and economic remediation technology to immobilize heavy metals in contaminated soils. In this study, quick lime (CaO) was used to immobilize cadmium and zinc present in waste mine contaminated clayey sand soils. Addition of 5% quicklime to the contaminated soils effectively reduced heavy metal leachability after 2 bed volume operation below the drinking water regulatory limits. Lime addition was revealed to increase the immobilization for all heavy metals in tested pH ranges, so it could be an optimal choice for short-term remediation of heavy metal contaminated soil. The mass balances for these column tests show metal reduction of 92% for Cd and 87% for Zn of total resolved mass in case of 5% lime application.

• Environmental Engineering Research
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• 제18권4호
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• pp.221-227
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• 2013

A risk assessment of environmental media was performed for the inhabitants in the area of the abandoned Nokdong metal mine. Soil, groundwater, and crop samples were collected from September to October 2008 around the mine. After pretreatment of these samples, metal concentrations were measured, and a risk assessment was performed using the Korean soil-contamination risk assessment guidelines. Lead (Pb) and arsenic (As) intake rates were the highest for inhalation of soil dust. The cancer risks from ingestion of As-contaminated groundwater, inhalation of As-, Cd-, and Pb-contaminated soils, and contact of As-contaminated soils exceeded the acceptable risk. The sum of all carcinogenic risks was $9.29{\times}10^{-3}$. The non-carcinogenic risk was highest for ingestion of As-contaminated water (11.0), followed, in descending order, by inhalation of Hg-contaminated soil and ingestion of Pb-contaminated water. Most of the risks were associated with As, Cd, Pb, and Hg contamination, and therefore, these metals were considered to be potential toxic carcinogens and non-carcinogens for humans in this area. In this study, the non-carcinogenic risks of ingestion of contaminated water or crops, as well as those associated with the inhalation of soil dust were observed.

• 한국지하수토양환경학회지:지하수토양환경
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• 제15권6호
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• pp.107-113
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• 2010

This paper presents the prediction of shear strength of oil contaminated clay using fall cone test used to determine the liquid limit of soil. The penetration depth of fall cone is related to water content of soil. Laboratory vane shear can also be related to water content. To explore the relative correlation between penetration depth of fall cone and laboratory vane shear, both fall cone tests and laboratory vane shear test were carried out with water contents of soil. The developed empirical relationships in this studys showed that the shear strength is reduced to 3.9% with 1% increase of oil content. And, the lesser initial water content of contaminated clay, the more shear strength of contaminated clay is affected by oil content.

• 물과 미래
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• 제6권2호
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• pp.19-29
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• 1973

The progressive contamination of water resulted from man's activity and the use of fertilizers is not restricted only to surface water, but also the shallow groundwater is affected. This type of groundwater contamination is mainly restricted to areas composed of permeable, nonconsolidated sediments forming a shallow aquifer. The chloride and the sulfate resulted from man's activity and the use of fertilizers were measured to study the variations of the groundwater contamination. In general, (1) When water level rises, the rate of groundwater contamination becomes less and when water level declines, the rate of contamination is increased. (2) The highly contaminated season is the early-summer and the less contaminated season is the winter or after rainy season. (3) The groundwater in weathering zone without covering layer. (4) The degree of contamination of wells is increased with the increase of well depth and lowing the water table, because of increasing contaminated water from enlargement of the area of influence of the well.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2001년도 추계학술대회(제116회) 및 13회 Workshop 제3회 한ㆍ일 치과보존학회 공동학술대회 초록집
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• pp.577-577
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• 2001

The lastest concepts in bonding are "total etch", in which both enamel and dentin are etched with an acid to remove the smear layers, and "wet dentin" in which the dentin is not blown dry but left moist before application of the bonding primer. Ideally, the application of a bonding agent to tooth structure should be insensitive to minor contamination from oral fluids. Clinically contaminations such as saliva, gingival fluid, blood and handpiece lubricant are often encountered by dentists during preparation of a restoration. The aim of this study was to evaluate the effect of contamination by hem-ostatic agents on shear bond strength of compomer restorations. One hundred and ten extracted human maxillary and mandibular molar teeth were collected. The teeth were cleaned from soft tissue remnant and debris and stored in physiologic solution until they were used. Small flat area on dentin of the buccal surface were wet ground serially with 400, 800 and 1200 abrasive paper on automatic polishing machine. The teeth were randomly divided into 11 groups. Each group was conditioned as follows: Group 1 : Dentin surface was not etched and not contaminated by hemostatic agents. Group2 : Dentin surface was not etched but was contaminated by Astringedent (Ultradent product Inc., Utah, U.S.A.). Group3 : Dentin surface was not etched but was contaminated by Bosmin (Jeil Phann, Korea.). Group4 : Dentin surface was not etched but was contaminated by Epri-dent (Epr Industries, NJ, U.S.A.). Group5: Dentin surface was etched and not contaminated by hemostatic agents. Group 6 : Dentin surface was etched and contaminated by Astringedent. Group7 : Dentin surface was etched and contaminated by Bosmin. Group8 : Dentin surface was etched and contaminated by Epri-dent. Group9 : Dentin surface was contaminated by Astringedent. The contaminated surface was rinsed by water and dried by compressed air. Group10 : Dentin surface was contaminated by Bosmin. The contaminated surface was rinsed by water aud dried by compresfed air. Group 11 : Dentin surface was contaminated by Epri-dent. The contaminated surface was rinsed by water and dried by compresfed air. After surface conditioning, F2000 was applicated on the conditoned dentin surface. The teeth were thermocycled in distilled water at $5^{\circ}C\;and\;55^{\circ}C$ for 1000 cycles. The samples were placed on the binder with the bonded compomer-dentin interface parallel to the lmife-edge shearing rod of the Universal testing machine(Zwick 020, Germany) running at a cross head speed of 1.0mmimin. There were no significant differences in shear bond strength between groups 1 and group 3 and 4, but group 2 showed significant decrease in shear bond strength compared with group 1. There were no significant differences in shear bond strength between group 5 and group 7 and 8, but group 6 showed significant decrease in shear bond strength compared with group 5. There were no significant differences in shear bond strength between group 5 and group 9, 10 and 11.

• 대한환경공학회지
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• 제33권9호
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• pp.670-676
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• 2011

인위적 중금속 오염 토양은 중금속용액과 토양 간 흡착평형, 여과 또는 원심분리, 건조과정을 거쳐 완성되어 토양세척 및 토양독성 실험에 널리 이용되고 있다. 그러나 많은 문헌에서 실험에 사용한 오염토양이 건조과정 이후 충분한 세척을 마친 후 사용되었는지 불분명하다. 본 연구는 중금속 오염 토양 제조 과정에서 최종 세척과정이 중금속 오염 농도에 미치는 영향을 파악하고자 하였다. 3가지 대표적 중금속 오염 토양 제조방법(슬러리 건조법, 평형 후 건조법, 여과 후 건조법)에 의한 중금속(Cd, Pb) 오염 농도 차이를 파악하고 이후 최종 세척과정이 제조 중금속 오염 토양 농도에 미치는 영향을 분석하였다. 중금속용액과 토양을 흡착평형 시킨 후 건조과정만을 거쳐 제조한 오염토양 내 중금속은 이후 단순 세척과정에서 50% 이상 용탈되는 것으로 나타났다. 중금속용액과 토양 간 흡착평형을 거쳐 중금속 오염 토양을 제조한 경우 실험 전 충분한 세척을 거치지 않는다면 이후 토양세척 및 토양독성 실험 결과에 지대한 영향을 미칠 것으로 예상된다. 그러므로 제조오염토양을 이용한 실험에서는 초기 중금속 농도 결정 시점을 중금속 흡착 완료 단계가 아닌, 흡착 후 충분한 세척이 완료된 이후 초기 토양중금속 농도로 결정하는 것이 바람직하다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 창립총회 및 춘계학술발표회
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• pp.84-89
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• 2000

Parametric studies based on laboratory pilot tests were performed to investigate the relationships between electrical resistivity and contaminated soil properties. Three kinds of sandy soils sampled and leachates from a industrial waste landfill were mixed to model the contaminated soils. Electrical resistivity of soils were measured by using a simulated resistivity cone penetrometer probe. In the experiments, the electrical resistivity were observed with changing the water content, void ratio, unit weight, degree of saturation, and concentration of the leachate. The test results show that the electrical resistivity of soils depends largely on the water content and the electrical property of pore water rather than unit weight and types of soils.

• The Korean Journal of Ecology
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• 제19권5호
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• pp.365-373
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• 1996

A survey was carried out to investigate the contamination of streams by the acid mine drainage originated from the abandoned coal mines and coal refuse piles. The physico-KDICical characteristics such as pH, sulfate and elements concentrations in the water and sediment in streams were analyzed. Microbial activity in the sediment was evaluated by measuring dehydrogenase activities. At sites contaminated by acid mine drainage, the pH of the water and sediment declined to acidic range from neutral due to the accumulation of sulfate. The dehydrogenase activity ranged from 12 to $170{\mu}g-TPF{\cdot}g-dry\;soil^{-1}{\cdot}24h^{-1}$ at the contaminated sites, whereas uncontaminated sites had activities of 1,176~4,259 ${\mu}g-TPF{\cdot}g-dry\;soil^{-1}{\cdot}24h^{-1}$. The dehydrogenase activity was significantly affected by low pH of the sediment, indicating that high concentration of sulfate inhibited microbial activity. The concentrations of heavy metals such as Pb and Fe in contaminated sdeiment (37~46 ppm Pb; 46,000~464,000 ppm Fe) were much higher than those in the uncontaminated sediment. The concentration of Al in the contaminated water acidfied by coal mine drainage was in the range of 11 to 42 ppm. Compared with those in the uncontaminated sediment, the concentrations of Mn, Mg and Ca in contaminated sediment were low because of the leaching from soil to water by the acidfied stream water.