• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.448-452
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• 2001

An Experimental study was carried out to develop a simple method of processing copper waste sludge which is produced by PBC manufacturing. The procedure is based on leaching of wet sludge in 2N H$_2$SO$_4$, and the solid / liquid ratio is controlled approximately at 1/10. The recovery of copper is 85.4%, and pH of the leachate is 3.20. Adding ammonia solution into leachate forms ammine, and hydroxide compounds derived from other impurities in leachate at pH 10. The hydroxide compound can be treated by ferrite process, and the product is a stable oxide compound. Then the ammine solution is heated to evaporate ammonia, and the copper hydroxide is formed. Heating at 8$0^{\circ}C$by aeration, copper hydroxide is transformed into copper oxide with a purity of 98.4%. This process can recover most copper from sludge and the residue can be stabilized by the formation of a stable oxide compound which is not hazardous to environment.

• 한국식품위생안전성학회:학술대회논문집
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• 한국식품위생안전성학회 1994년도 하계 학술 심포지움
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• pp.7-15
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• 1994

Dietary life of Korean population was greatly improved by the increased food production, enlarged food processing and betterment of food distribution system during the last three decades. On the other hand, food pollution issues have arisen from the increased use of chemicals and advancements in analytical techniques and toxicological information. The health risk of hazardous substances in Korean diet was estimated to be in the decreasing order of heavy metals>pesticide residues>food additives>mycotoxins>radionuclides>PCBs whereas consumers do not recognize it in the same order. It is needed to evaluate the food safety more accurately based on scientific evidences and to adopt reasonable regulatory measures in Korea for the benefits of people's health and national interest.

• 한국환경과학회지
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• 제2권1호
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• pp.9.2-19
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• 1993

A laboratory study was conducted to investigate the immobilization of the laboratory waste sludge, mainly from chemical oxygen demand (COD) waste, using cementitious binders. The binders were: Ordinary Portland Cement (OPC), and lime-Rice Husk Ash (RHA) cement. The economic evaluation was done for three different kinds of cementitious binders, namely, OPC, Portaind Rice Husk Ash Cement (PRHAC) which contained rice husk ash U percent by dry weight, and lime-RHA cement. The result showed that lime-RHA cement was the cheapest. The applicability of Freundlich's desorption isotherm was studied to assess the teachability of sludges. The teachability of cement mortars was found to follow the desorption isotherms. Therefore, it was concluded that based on this test, the leachate concentrations of the solidified heavy metals could be predicted, approximately by the Freundlich's isotherm desorption modeling.

• 한국생산제조학회지
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• 제18권3호
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• pp.300-306
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• 2009

Welding technology is applicable in many kinds of fields, with the help of its advantages such as easy operational procedure and structural simplification. However, in the process of welding, hazardous materials and fumes cause huge fire broke-outs, explosions, and health-conscious problems. Also, as heavy metals in fumes have a harmful effect on the environment, recently, this has emerged as a urgent social issue. This study has been aimed at the recommendation of the most environment-friendly, among materials currently used in plumbing welding, and it has been done at the result of the analysis of amount, ingredient, and size in collected fumes created in the experiment of welding five rods to galvanized steel pipes and steel pipe ones. At the test result, due to the effect of Zn-coating, galvanized steel pipes, when welded to rods, created more fumes than steel pipe ones. In the mean time, when it comes to welding rods, among five, WR-03 produced fumes the least. Therefore, a combination of the test results clearly indicates that the case of welding WR-03 to cast-iron pipes turned out to be the most environment-friendly.

• Journal of Microbiology and Biotechnology
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• 제30권5호
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• pp.681-688
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• 2020

Bacterial cell-based biosensors, or whole-cell bioreporters (WCBs), are an alternative tool for the quantification of hazardous materials. Most WCBs share similar working mechanisms. In brief, the recognition of a target by sensing domains induces a biological event, such as changes in protein conformation or gene expression, providing a basis for quantification. WCBs targeting heavy metal(loid)s employ metalloregulators as sensing domains and control the expression of genes in the presence of target metal(loid) ions, but the diversity of targets, specificity, and sensitivity of these WCBs are limited. In this study, we genetically engineered the metal-binding loop (MBL) of ZntR, which controls the znt-operon in Escherichia coli. In the MBL of ZntR, three Cys sites interact with metal ions. Based on the crystal structure of ZntR, MBL sequences were modified by site-directed mutagenesis. As a result, the metal-sensing properties of WCBs differed depending on amino acid sequences and the new selectivity to Cr or Pb was observed. Although there is room for improvement, our results support the use of currently available WCBs as a platform to generate new WCBs to target other environmental pollutants including metal(loid)s.

• 한국환경농학회지
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• 제5권1호
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• pp.43-47
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• 1986

온산(溫山)공업단지 조성(造成)에 따른 농작물(農作物)의 오염(汚染)가능성을 조사하기 위하여 1978년 3월부터 12월에 걸쳐 주변 농경지에서 재배된 농작물(農作物)(수도, 보리, 대두, 채소, 과일)중의 중금속 농도를 분석한 결과는 다음과 같다. 중금속 함량은 농작물의 종류, 부위, 재배지역에 따라 약간의 차이가 있었으나 일정한 경향은 찾아 볼 수 없었다. 분석한 농작물 시료의 평균치(平均値)를 보면(풍건물(風乾物)기준) As 0.23 ppm, Cd 0.46 ppm, Cu 4.88 ppm, Hg 0.09 ppm, Pb 3.86 ppm, Zn 41.3 ppm으로서 이 지역에 대한 자연함유량(自然含有量) 기준(基準)으로 이용할 수 있을 것이다.

• 융합정보논문지
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• 제10권12호
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• pp.208-215
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• 2020

본 연구는 SUKI를 활용하여 두피의 중금속 감소에 대해 미치는 영향에 대해 알아보았다. 연구대상자는 총 26명이었으며 실험군과 대조군 각각 13명이었다. SUKI 도구를 활용한 두피 중금속 배출에 대한 중재를 8주간 주 2회씩 실시하였고, 결과는 다음과 같다. 총 각각 8 종목의 실험군과 대조군의 비교에서 실험군에서 유의한 차이가 있었다. 실험군의 중금속인 Hg, Pb, Al, Cd, As, Ba, Ur, Cs 중에서 6가지 항목의 Hg, Al, Cd, As, Ba, Ur과 같은 중금속들에서 통계적으로 유의한 감소(p<.05)를 보여주었으며, Pb, Cs 는 유의하지 않았다. 그리고 해당 유해중금속 중에서 Al, Ba, Hg가 가장 큰 차이의 감소율을 나타냈다. 따라서 SUKI 도구의 중재가 일부 중금속 배출에 영향을 줄 수 있다는 것을 시사한다(p<.05). 결론적으로 향후 지속적인 연구를 통해 두피의 중금속 배출을 위한 기초자료로 활용될 수 있을 것으로 사료된다.

• 한국식품위생안전성학회지
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• 제35권6호
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• pp.581-586
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• 2020

본 연구는 현재 유통 중인 다이어트 제품 62건에 대한 부정유해물질의 실태조사를 위하여 비만치료제 및 그 유사물질 6종(오르리스타트, 시부트라민, 데스메틸시부트라민, 디데스메틸시부트라민, 클로로시부트라민, 클로로시펜트라민)과 중금속(납, 카드뮴, 비소) 함량을 조사하였다. 연구결과, 다이어트 제품 62건에 대하여 비만치료제 및 그 유사물질 6종은 검출되지 않았다. 중금속은 납, 카드뮴, 비소 각각 다류의 경우 ND-0.177 mg/kg, 0.002-0.233 mg/kg, 0.001-0.188 mg/kg, 캔디류의 경우 ND-0.370 mg/kg, 0.003-0.057 mg/kg, 0.007-0.120 mg/kg, 체중조절용조제식품의 경우 ND-0.055 mg/kg, 0.012-0.045 mg/kg, 0.010-0.163 mg/kg의 함량을 나타냈다. 기준 규격이 설정되어있지 않은 기타가공식품의 경우 납, 카드뮴, 비소 각각 ND-2.324 mg/kg, 0.004-0.936 mg/kg, 0.003-21.247 mg/kg의 함량을 보였으며, 비소의 경우 2건이 PTWI 기준치 이상의 수치를 보였다. 결과적으로 식품군의 안전관리를 위하여 향후 기준 규격이 없는 기타가공식품 유형에 대한 적절한 기준 설정이 필요할 것으로 사료된다.

• Journal of Ecology and Environment
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• 제47권3호
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• pp.157-167
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• 2023

Background: The most hazardous wastewater sources in the northern part of the Middle Nile Delta, Egypt; receiving a massive amount of agricultural, industrial, and sewage drainage are Kitchener drain which is one of the tallest drainage systems, and Burullus Lake which represents the 2nd largest Egyptian coastal lake. Results: The current work is to determine the abundance and frequency of cyanophytes, chlorophytes, and bacillariophytes and the correlation between them and environmental abiotic components. Among sixty nine microalgal species, 19 species are belong Cyanophyta, 26 belong Chlorophyta and 24 belong Bacillariophyta. Genus Scenedesmus (Chlorophyta) was the most abundant in the study area (13 species), followed by Genus Oscillatoria (9 species) and Genus Navicula (7 species). Nostoc muscorum and Chlorella vulgaris were the most common and recorded in all sites (100% of the locations) under study. The application of the two-way indicator species analysis (TWINSPAN) and detrended correspondence analysis revealed agglomerating of 4 groups (communities) at 4th level of classification and reasonable segregation between these groups. Zinc, cadmium and lead were showed the highest levels (0.26±0.03, 0.26±0.06, and 0.17±0.01 ppm, respectively). Conclusions: The correlation analysis between water and community variables indicated a high negative correlation of total algae richness with nickel (r = -0.936, p < 0.01). Cyanophyta and Bacillariophyta were correlated negatively (r = -0.842, p < 0.01). However, Chlorophyta showed a negative richness with each of Ni and Pb (r = -0.965, -0.873, respectively) on one hand and a high positive correlation was revealed (r = 0.964) with all environmental variables on the other hand.

• 한국건설순환자원학회논문집
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• 제1권3호
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• pp.204-210
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• 2013

상동지역 중석광 광미의 품질 특성을 파악하기 위해 XRD 및 PSA를 사용하여 광물학적인 특성을 검토하였다. XRD분석 결과 상동지역 중석광 광미내에는 석영(quartz), 녹니석(chlorite), 회장석(anorthite) 그리고 코디에라이트(cordierite) 등이 함유되어 있는 것으로 파악되었다. 또한, 상동지역 중석광 광미의 용출 특성을 파악하기 위해 광미를 혼합한 모르터를 제작하여 KSLT의 규정에 의해 실험한 결과 폐기물 관리법 시행규칙에 제시된 유해물질 함유 기준값 보다 낮은 결과를 나타내었으며, 특히, 고루슬래그 미분말의 혼합률이 증가할수록 중금속의 농도는 감소함을 알 수 있다.