• 한국식품과학회지
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• 제18권4호
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• pp.264-269
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• 1986

식품원료의 조리(調理) 및 가공(加工)중 오염된 중금속(重金屬)의 함량변화를 규명하기 위해 쌀과 밀가루를 시료로 수세(水洗), 취반(炊飯)과정 그리고 쿠키, 국수, 빵으로의 가공(加工)중 카드뮴(Cd) 및 납(Pb) 함량의 변화를 측정하였다. 중금속을 인위적으로 오염시킨 쌀을 4희 수세하였을때 Cd는 39.2%, Pb는 34.9%제거되었다. 쌀을 3회 수세후 취반하였을 때 전기밥솥의 경우 Cd는 14.3%, Pb는 17.0% 제거되었으며 압력밥솥의 경우 Cd는 25.5%, Pb는 27.4%가 제거되었다. 취반시 Cd와 Pb의 제거효율을 자연적으로 오염된 쌀과 인위적으로 오염시킨 쌀 간에 또는 전기밥솥과 압력밥솥 간에 유의적인 차이가 없었다. 중금속으로 오염된 밀가루로 쿠키를 구울 때와 제빵시 Cd와 Pb의 제거효과는 기대할 수 없었다. 밀가루로 칼국수를 만들고 이것을 삶았을 때 Cd 및 Pb 함량은 국수 고형물에 75%. 국물에 25%가 이 동하였다.

• 유기물자원화
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• 제21권3호
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• pp.53-63
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• 2013

중금속에 의한 토양오염문제는 주로 폐 금속광산의 주변 농경지등에서 발생되어져 왔으며 이를 해결하기위한 비용은 수질이나 대기오염에 비해서 훨씬 크며 시간도 많이 소요되어진다고 알려져 있다. 지금까지 중금속으로 오염된 토양을 복원시키기 위한 경제적이고 실용적인 많은 기술들이 개발되어지고 제안되어져 왔다. 그래서 본 연구에서는 최근까지 국내/외에서 개발되어지거나 실용화되어지고 있는 다양한 기술들의 특성 및 장 단점 등에 대하여 고찰하고자 한다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.334-337
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• 2002

The drinking water industry faces a growing number of difficultiesin the treatment of groundwater for drinking water production. Groundwater sources are frequently contaminated with nitrates and phosphates due to usage of chemical fertilizer In this study, feasibility of micellar enhanced ultrafiltation (MEUF) was investigated to remediate groundwater contaminated with nitrate and phosphate. Ultrafiltration membrane was cellulose acetate with molecular weight cut off (MWCO) 10,000 and celtyl pyridinium chloride (CPC) was used to form pollutant-micelle complex with nitrate and phosphate. The results show that nitrate and phosphate rejections are satisfactory. The removal efficiency of nitrate and phosphate show 80% and 84% in single pollutant system, respectively with 3 molar ratio of CPC to pollutants. In the multi-pollutant systems, the removalefficiency increased to 90 % and 89 % for nitrate and phosphate, respectively, The presence of nitrate in the solutions did not affect the removal of phosphate and that of phosphate did not affect the removal of nitrate. The concentration of CPC in the permeate and removal efficiency of CPC was a function of the concentration of CPC in the feed solutions.

• 물과 미래
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• 제23권4호
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• pp.477-486
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• 1990

지하수 오염처리에 관한 문제는 수공학 이외에도 지질학, 화학, 독극물학 등의 전문지식이 요구된다는 점에서 Expert System(이하 ES)가 설계되기에 이상적인 환경을 지니고 있는 분야이다. 본 연구의 목적은 오염물질로 오염된 지하수의 처리에 대한 조언과 그것에 대한 추적을 위한 소프트웨어의 개발에 있다. Prolog 언어를 사용하여 개발된 이 프로그램은 현장 실무자에게 독극성의 정도와 화학반응의 축연성, 특정지점의 농도계산을 통하여 현 상황에 대한 심각성의 정도와 대응책을 조언하게 된다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.418-421
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• 2003

Surfactant enhanced in-situ soil flushing was peformed to remediate the soil and groundwater at an oil contaminated site, and the effluent solution was treated by the chemical treatment process including DAF(Dissolved Air Flotation). A section from the contaminated site(4.5m$\times$4.5m$\times$6.0m) was selected for the research, which was composed of heterogeneous sandy and silt-sandy soils with average Hydraulic conductivity of 2.0$\times$10$^{-4}$ cm/sec. Two percent of sorbitan monooleate(POE 20) and 0.07% of iso-prophyl alcohol were mixed for the surfactant solution and 3 pore volumes of surfactant solution were injected to remove oil from the contaminant section. Four injection wells and two extraction wells were built in the section to flush surfactant solution. Water samples taken from extraction wells and the storage tank were analyzed by GC(gas-chromatography) for TPH concentration with different time. Five pore volumes of solution were extracted while TPH concentration in soil and groundwater at the section were below the Waste Water Discharge Limit(WWDL). Total 18.5kg of oil (TPH) was removed from the section. The concentration of heavy metals in the effluent solution also increased with the increase of TPH concentration, suggesting that the surfactant enhanced in-situ flushing be available to remove not only oil but heavy metals from contaminated sites. Results suggest that in-situ soil flushing and chemical treatment process including DAF could be a successful process to remediate contaminated sites distributed in Korea.

• 한국물환경학회지
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• 제20권5호
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• pp.512-519
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• 2004

Hybrid barriers using reduction and immobilization were tested to remediate the groundwater contaminated with multi-pollutants in this study. Iron filings and HDTMA(hexadecyltrimethylammonium)-bentonite were simulated in columns to assess the performance of hybrid barriers for remediation of trichloroethylene(TCE)-contaminated water. TCE reduction rate for the mixture of iron filings and HDTMA-bentonite was about 7 times higher than that for iron filings, only suggesting the reduction of TCE was accelerated when HDTMA-bentonite was mixed with iron filings. TCE reduction rate for the two layers of iron and HDTMA-bentonite was nearly similar to that for iron filings alone, but the partition coefficient($K_d$) for the two layers was 4.5 times higher than for that iron filings only. TCE was immobilized in the first layer with HDTMA-bentonite, and then dechlorinated in the second layer with iron filings. HDTMA-bentonite may contribute to the increase in TCE concentration on iron surface so that more TCE can be reduced. Also, TCE removal in the hybrid barriers was not affected by chromate and naphthalene while the reduction rate of TCE with the co-existing contaminants by iron filings was significantly decreased. Significant TCE removal in this research indicates that the proposed hybrid barrier system has the potential to become the effective remediation alternative during the occurrence of oil shock. Also, if subsurface environments are contaminated with multi-pollutants that contain non-reducible compounds as well as reducible compounds such as TCE, the conventional reactive barriers cannot be applied to this subsurface environment, while the proposed hybrid system can be applied successfully.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권1호
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• pp.13-21
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• 2012

This study reports a surfactant-enhanced in-situ remediation treatment at a test site which is located in a hilly terrain. The leakage oils from a storage tank situated on the top of the hill contaminated soils and groundwater in the lower elevation. Sixteen vertical injection wells (11 m deep) were installed at the top of the hill to introduce 0.1-0.5 vol.% of non-ionic Tween-80 surfactant. The contaminated area that required remediation treatment was about $1,650\;m^2$. Two cycles of injecting surfactant solution followed by water were repeated over approximately 7.5 months: first cycle with 0.5 month of surfactant injection followed by 3 months of water injection, and second cycle with 1 month of surfactant followed by 3 months of water injection. The seasonal fluctuation in groundwater table was also considered in the selection of periods for surfactant and water injection. The results showed that the initial Total Petroleum Hydrocarbon (TPH) concentration of 1,041 mg/kg (maximum 3,605 mg/kg) was reduced significantly down to 76.6 mg/kg in average. After 2nd surfactant injection process finished, average TPH concentration of soils was reduced to 7.5% compared to initial concentration. Also, average BTEX concentration of soils was reduced to 10.8%. This resultes show that the surfactant enhanced in-situ remediation processes can be applicable to LNAPL contaminated site in field scale.

• Restorative Dentistry and Endodontics
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• 제21권2호
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• pp.585-601
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• 1996

The purpose of this study was to elucidate the effect of blood-and saliva-contamination during dentin pretreatment procedure on tensile bond strength, and to investigate the effect of contaminant-removing treatments on the recovery of bond strength of dentin bonding agents. Dentin specimens prepared from freshly extracted bovine mandibular anterior teeth were divided into non-contaminated control and contaminated experimental groups. The specimens of the contaminated group were contaminated with saliva or blood after etching or priming procedure, followed by contaminant-removing treatments. All the specimens were bonded with All Bond$^{(R)}$ 2 dentin bonding agent and Bisfil$^{TM}$ composite resin or Scotchbond$^{TM}$ Multipurpose and Z100. After all the bonded specimens were stored in $37^{\circ}C$ distilled water for 24 hours, tensile bond strengths were measured. The contaminated dentin and fractured dentin surfaces were examined under the scanning electron microscope. The results were as follows : Contaminated specimens showed lower bond strength than non-contaminated ones regardless of the kind of contaminant, contamination time and contaminant-removing treatments, except specimens which were acid-etched following saliva contamination after etching in All Bond$^{(R)}$ 2 groups (p<0.05). Blood contaminant resulted in much bond strength decrease than saliva ones (p<0.01), and contamination after priming resulted in much decrease in bond strength than after etching (p<0.01). Re-etching resulted in increase of bond strength in the specimens contaminated with saliva after etching but not in blood contaminated ones. Re-priming resulted in increase of bond strength in the specimens contaminated after priming regardless of the kind of contaminant.

• Parasites, Hosts and Diseases
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• 제43권2호
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• pp.47-50
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• 2005

A survey was carried out from August to December 2004 in Pusan, Korea to document the presence of free-living amoeba (FLA), including the genus Acanthamoeba, in both contact lens storage cases and domestic tap water. Acanthamoeba was isolated from $5(4.2\%)$ in 120 contact lens storage cases. Four house tap water samples from residents, whose contact lens storage cases had been contaminated by Acanthamoeba, were also found to be contaminated with Acanthamoeba. Therefore, the contamination rate of FLA and Acanthamoeba in domestic tap water was investigated in order to examine the role of domestic tap water in Acanthamoeba contamination of contact lens storage cases. FLA and Acanthamoeba were identified in $97(46.8\%)\;and\;16(7.7\%)$ of the 207 domestic tap water samples, respectively. There were no significant differences between the contamination rates of FLA in tap water according to the filtration plant of origin. No FLA was detected in the tap water directly supplied by the water purification plants. Water storage tanks appear to promote FLA colonization, including Acanthamoeba, in domestic tap water. This increases the risk of Acanthamoeba contamination in contact lens storage cases as well as increasing the risk of Acanthamoeba keratitis.

• 한국식품과학회지
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• 제47권6호
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• pp.719-724
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• 2015

넙치, 방어 어류 2종과 가리비, 참굴 패류 2종에 수산식품의 주요 식중독균인 장염비브리오균(V. parahaemolyticus)을 인위적으로 오염시킨 후, 강산성차아염소산수와 미산성차아염소산수의 살균효과를 조사한 결과를 요약하면 다음과 같다. 넙치에 장염비브리오균을 인위적으로 오염시킨 후, 강산성차아염소산수 및 미산성차아염소산수 공히 10배의 양으로 세정한 결과, 약 4.0 log가 감소하였으며, 30배의 양으로 세정한 경우, 검출한계 이하로 나타나 강력한 살균효과가 있는 것을 확인하였으며 방어에 있어서도 넙치와 비슷한 결과를 확인하였다. 가리비에 장염비브리오균을 인위적으로 오염시킨 후, 강산성차아염소산수 및 미산성차아염소산수 공히 10배의 양으로 세정한 결과, 약 4.2 log가 감소하였으며, 30배의 양으로 세정한 경우에는 장염비브리오균이 검출되지 않아 강력한 살균효과를 나타내었다. 참굴에 장염비브리오균을 인위적으로 오염시킨 후, 강산성차아염소산수 및 미산성차아염소산수 공히 10배의 양으로 세정한 결과, 약 3.8 log가 감소하였으며, 30배의 양으로 세정한 경우, 7.0 log가 감소하여, 강력한 살균효과가 있는 것을 확인하였지만 넙치, 방어, 가리비에 비해서는 살균효과가 다소 낮게 나타났다. 어류 근육이나 가리비에 비해 참굴에 오염된 장염비브리오균에 대한 차아염소산수의 살균효과가 다소 떨어지는 것은 참굴의 표면 구조의 복잡성 때문인 것으로 판단된다.