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        검색결과 1,696

        1101.
        2013.01 KCI 등재 서비스 종료(열람 제한)
        The purpose of this study is to assess the effects of heavy metal concentrations in the blood and urine of the general population. This research had been conducted from April to December 2008, studying 545 residents of Daejeon and Chungcheong Province. Through the concentrations of heavy metals(Pb, Cd, Hg, As, Mn) in the biota samples and questionnaires, the residents heavy metal exposure level and the influential factors according to personal characteristics or lifestyle were evaluated. As to the heavy metal concentration in the blood and urine of the comparing region, were As and Mn statistically significant(p<0.01, p<0.05). Blood lead and urinary mercury concentrations were higher in males than females. The heavy metal concentration for each age group increased blood mercury. The concentration of all heavy metals were higher in the drinkers than in the non-drinkers. Blood lead and mercury concentrations were higher in the smokers than in the non-smokers, but the urinary cadmium, arsenic and blood manganese was higher in the non-smokers than in the smokers. As to the blood lead and urinary cadmium concentration according to the food preference fish showed high concentration. To clarify the factors affecting the heavy metal concentration in biota among subjects multiple regression analysis was conducted. As a results, it turned out that as to lead content in blood, sex, age and smoking have influence on the subjects with explanatory adequacy of 14.0 %. These results demonstrated that the factors affected the concentrations of heavy metals in blood and urine. The results of this study could be used as the foundational data for setting the health risk assessment.
        1102.
        2012.12 KCI 등재 서비스 종료(열람 제한)
        The objective of this study was to evaluate the immobilization of heavy metals (Cu, Pb, Zn and Cd) in an abandoned mine soil by applying both soluble phosphates and steel slag as stabilizers. The application rate of stabilizers to soils was determinated based on PO4/Pb molar ratio of 2.0 for phosphates and on weight/weight ratio of 2, 5, 10% for steel slag, respectively. Immobilization efficiency of heavy metals in the contaminated soils was evaluated by toxicity characteristics leaching procedure (TCLP). After adding both phosphate and slag, the immobilization efficiencies of Cu, Zn and Cd increased significantly (about 14% - 40%) compared to those of treatment with soluble phosphate alone. The increae in immobilization efficiencies of Cu was the greatest. Whereas, immobilization efficiency of Pb was not significantly different from those with soluble phosphate alone. Among the tested three phosphates (Na2HPO4 ·12H2O, Ca(H2PO4)2 ·H2O, (NH4)2HPO4), the immobilization efficiencies with Na2HPO4 ·12H2O increased more than those of other phosphates. Results of sequential extraction analysis indicated that fraction of reducible form (F3) and residual form (F5) increased, while mobile forms (F1, and F2) decreased after immobilization treatment with both stabilizers resulting in decrease in leachability of heavy meyals in the treated soils. Residual fraction of Cu after treatnment was the highest as 68.5%, it was followed by Cu > Pb > Zn > Cd.
        1103.
        2012.12 KCI 등재 서비스 종료(열람 제한)
        The amount of contaminated dredged materials are increasing every year in Korea. Secondary contamination would be expected, if contaminated marine clayey slurry remains without treatment. Therefore, the appropriate remedial treatments are required in order to prevent secondary contamination. Electrokinetic method is especially suitable for low permeability dredged clayey soils because pore fluid can be easily transported by electric field. Hydrogen ions created by electrolysis enhance the remedial processes by desorbing heavy metal contaminants from slurry soil surfaces. This study investigated variation of electrical current and voltage gradient during the treatment, and ICP analysis as well as pH measurements were carried out to measure zinc concentration during and after the treatment.
        1104.
        2012.12 KCI 등재 서비스 종료(열람 제한)
        This study was conducted to determine the contents of heavy metal in commercial herbal medicines. The monitoring of lead, arsenic, cadmium and mercury was carried out on 100 samples with 10 kinds of herbal medicines. The contents of heavy metal were measured by inductively coupled plasma atomic emission spectrometry (ICP-AES) and mercury analyzer. The mean values of heavy metal contents for herbal medicines were Pb 1.87 mg/kg, As 0.39 mg/kg, Cd 0.26 mg/kg and Hg 0.021 mg/kg. Of the total samples, 19 samples (19%, 4 types) were violated the KFDA regulatory guidance of heavy metal in herbal medicines (9 samples on Pb, 10 samples on Cd). Among these 19 unsuitable samples, 16 samples were domestic and 3 samples were imported. Therefore, we need continuously monitoring to ensure confidence and safety for these herbal medicines.
        1105.
        2012.12 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        원전에서 발생되는 방사성폐기물에 대한 고화처리 방법 중 하나인 유리화기술이 일부 가연성폐기물에 대해 적용되고 있다. 국내외적으로 중저준위 방사성폐기물의 효과적인 감용과 안정적인 처분을 위해 다양한 폐기물에 대한 유리화기술 적용방안이 확대 연구되고 있으며, 최근에는 가연성폐기물 뿐만 아니라 알루미늄 금속과 같은 비가연성폐기물에도 유리화 연구가 활발하게 진행되고 있다. 공기조화계통 (HVAC)에는 주로 필터가 이용되고 있으며, 사용 후 필터는 여과재 (유리섬유 및 알루미늄)를 이용하여 배기체를 흡착하기 때문에 방사성폐기물로 처리가 되어야 한다. 본 연구는 필터에 대한 처리기술 연구를 위해 유도가열식 저온용융로 (Cold Crucible Induction Melter: CCIM)를 이용한 유리화 타당성 연구를 수행하였다. 사용후 필터에 대한 유리화 (Vitrification)는 먼저 유리섬유 및 알루미늄 함량을 고려한 최적의 유리조성을 개발 하였으며, 개발된 유리조성을 이용하여 최적의 폐기물 저감을 위한 용융변수와 최종 생성된 유리고화체의 특성을 분석하였다. 사용후 필터 유리화용 조성유리는 주로 SiO2와 B2O3로 구성되어 있다. 전기로를 이용한 용융물 특성시험에서는 폐기물 투입률 및 최종 생성물인 유리고화체의 특성이 검토되었다. 본 연구에서는 알루미늄 금속과 유리섬유로 구성된 필터에 대한 유리조성 개발과 이를 통해 생성된 유리고화체의 물리화학적 특성을 검토하고 유리화 타당성을 확인하였다.
        1106.
        2012.11 KCI 등재 서비스 종료(열람 제한)
        Waste dusts generated from various metallurgical processes were investigated for effective management of the designated waste in South Korea. Source of the study were selected based on the industries registered on the Allbarosystem. Raw material, products and manufacturing process were investigated on-site and leaching behavior of six heavy metals (Cr6+, Cd, Cu, Pb, Hg, As) along with CN was studied in 41 waste dust samples. We identified 14 samples exceeded the Korean regulation standard out of which 5 samples were designated waste. We suggest that regular monitoring is essential for the proper management.
        1107.
        2012.11 KCI 등재 서비스 종료(열람 제한)
        This paper describes the domestic and international status for melt decontamination, which has been known as the most effective technology for the volume reduction and recycling of the metal wastes generated from nuclear facilities. The recycle or self disposal of metallic wastes can be considered as one of the waste management options under the circumstances of the capacity limitation of a waste disposal in Korea. The limited recycle or self disposal of the metal wastes through an melt decontamination have the merit from the positive view point of the increase in resource recyclability as well as the decrease in the amount of wastes to be disposed resulting the reduction of disposal cost and the enhancement of disposal safety. Among the scenarios for recycle and reuse of the radioactive metallic wastes, the most feasible and reasonable one is limited reuse option, in which the ingot can be recycled as the products such as the waste drums and ISO containers. Prior to recycle and reuse in the nuclear sector, however, the regulatory criteria for the recycle and reuse of metallic wastes should be established in parallel with the development of the recycling technology.
        1108.
        2012.10 KCI 등재 서비스 종료(열람 제한)
        The objective of this study was to evaluate the immobilization efficiency and sequential extraction of soluble phosphates (Na2HPO4 ·12H2O, Ca(H2PO4)2 ·H2O, (NH4)2HPO4) for the stabilization of heavy metals (Cu, Pb, Zn and Cd) in abandoned mine soil. The application rate of stabilizers to soils was determinated PO4/Pbtotal molar ratio of 0.5, 1.0, 2.0, 4.0. The immobilization efficiency was evaluate of TCLP (EPA method 1311) used in a landfill for heavy metals. After processing stabilization, the immobilization efficiency of Pb is more than 95% at molar ratio of 2.0 regardless kind of phosphate. For Cu Zn and Cd, on the other hand, the efficiency has the range of from 30% to 50%, even though molar ratio increase up to 4.0. It is relatively low in comparison with Pb. Leachability of heavy metals was reduced with increasing amounts of added phosphate. Phosphates, Na2HPO4 ·12H2O was more immobilization than Ca(H2PO4)2 ·H2O, (NH4)2HPO4. After sequential extraction, form of heavy metals in soil tends to increase strongly bond like forms of organic matter-bound(F4) and residual (F5). Especially the stable residual form increases in all metals. The growth rate of residual fraction was a little different heavy metals. The growth rate of Zn is greatest increased from 17% to 22% than other metals, it was followed by Zn > Cd > Pb > Cu. Phosphates, Ca(H2PO4)2 ·H2O was the greatest increased for residual fraction.
        1109.
        2012.10 KCI 등재 서비스 종료(열람 제한)
        The effects of sole, mixture heavy metals and soil samples was assessed based on the seed (Lactuca sativa L.) germination. In general, tested sole metals were showed considerable sensitivity on the germination, showing following EC50s: As(III) 1.02 mg/L, Cr(VI) 1.33 mg/L, Cu 2.26 mg/L, Cd 2.61 mg/L, As(V) 3.00 mg/L. Though obvious patterns were not observed on the effects by binary mixture metal, generally more synergistic mode was observed rather than antagonistic or additive. No significant correlation between toxicity and total metal contents was observed, but two groups classified according to contaminated arsenic concentration, showed considerable differences. Interactive effects of metals may vary depending on the bioassays used as well as on the mixture metals and their respective concentrations. Therefore, more detailed evaluation, such as with battery of assays, sample grouping and various mixtures, may comprise a useful tool for the assessment of the environmental samples with mixture contaminants.
        1119.
        2012.09 KCI 등재 서비스 종료(열람 제한)
        There are some problems of lacking the information on the safety of cement products and for determining harmfulness due to differences in the concentrations of heavy metals according to organizations. Thus, the harmfulness of heavy metals in cement products has been monitored by one time per month since August 2008 and the results have also been noticed for every month. In this study, the concentrations of seven different heavy metals (Cr(Ⅵ), T-Cr, Cd, Cu, Pb, As, and Hg) in cement products collected from 11 factories of 9 manufacturers are verified for every month and changes in the concentrations are also compared with the cement products of Japan, Germany, USA, and China. The company, HO, in domestic companies represents the highest values in four items and AJ shows the next high values. Thus, regarding these two manufacturers, it is necessary to take an effort for reducing the concentrations of five heavy metals through considering the major and alternative raw materials for producing their cement products. the chrome conversion rates in domestic cement products are about 36.4 % and that exhibits higher rates about 16.0 % and 8.3 %, 2.3 and 4.3 times, than that of Japan and USA, respectively.
        1120.
        2012.09 KCI 등재 서비스 종료(열람 제한)
        An issue of environmental pollutions has been aroused according to increases in recycling alternative raw materials and alternative fuels, which are the inputed wastes of cement kilns in Korea. Also, the infections of heavy metals in cement products on healths and environments have been issued by the National Assembly and the press. Thus, in this study, a total of 198 waste samples, 109 alternative raw material samples and 89 alternative fuel samples, which are the coprocessing wastes in eight major cement producers in Korea, are collected for two months. Then, 18 different heavy metals according to types of wastes are analyzed and the concentrations of the alternative raw materials and alternative fuels are investigated for comparing them with the foreign management guidelines. In the case of the alternative raw materials, although arsenic, cadmium, and copper do not exceed the domestic autonomy agreement guideline, lead exceeds the autonomy agreement guideline, 1,000 mg/kg. In the case of mercury, it satisfies the references of domestic guideline (2.0 mg/kg), Switzerland criteria (0.5 mg/kg), and France criteria (10.0 mg/kg). In the case of the alternative fuel, arsenic, cadmium, copper, and lead satisfy the autonomy agreement guideline, and the average content concentration of Hg represents 0.7702 mg/kg and that satisfies the references of autonomy agreement guideline (1.2 mg/kg) and France criteria (10.0 mg/kg). However, it slightly exceeds the references of Germany guideline (0.6 mg/kg) and Switzerland criteria (0.5 mg/kg). In particular, some of dust, WDF, waste synthesis resin, and purified oil show a high detection level in mercury and that leads to increase the average concentration. In addition, by investigating the concentration of heavy metals in various auxiliary wastes loaded to cement kilns in Korea, a management reference for such alternative raw materials and alternative fuels for future cement kilns in stages is proposed.