• 한국토양비료학회지
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• 제47권3호
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• pp.172-178
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• 2014

Soil properties and heavy metal (HM) concentrations in the field soils where balloon flowers (Platycodon grandiflorum, BF) were cultivated, were investigated together with HM (Cd, Cu, Pb, and Zn) accumulation by the BF roots. Basically, in most soils examined (51-97% among 65 samples), the chemical properties including soil pH, organic matter, available-P, and exchangeable cation contents appeared to be lower than the optimal ranges for balloon flower cultivation. There were no samples exceeding the standard limits for HM in soils. Instead, the total HM concentration levels in soils appeared to be maintained at around background levels for general soil in Korea. This implied that elevated HM accumulation in the soils caused by any possible input sources was unlikely. Even though the BF cultivated soils were not contaminated by HM, it was appeared that substantial amount of Cd was accumulated in BF roots with 1.5% and 35% roots samples exceeding the standard limits legislated for BF root ($0.81mg\;kg^{-1}DW$) and herbal plants ($0.3mg\;kg^{-1}DW$), respectively. This implied that the soil HM standard limits based on the total concentration does not reflect well the metal accumulation by plants and also it is likely that the Cd standard limits for BF and herbal plants is too restrict.

• Asian Pacific Journal of Cancer Prevention
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• 제14권6호
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• pp.3393-3402
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• 2013

The increasing scourge of cancer epidemiology is a global concern. With WHO emphasizing that 40% of all cancer cases are preventable, exposure to known and suspected carcinogens must be discouraged. The battle with communicable diseases and other third world challenges has greatly de-emphasized anti-cancer campaigns in sub-Saharan Africa. The abundant deposit of mineral resources in sub-Saharan Africa has attracted high mining activity with its negative environmental aftermath. Poor regulatory mechanisms have led to environmental contamination by products of mining including heavy metals. In addition to poor urban planning, the springing up of settlements in industrial areas has led to generation and exposure to more hazardous wastes consequent on poor disposal systems. Studies establishing close association between exposure to heavy metals and cancer epidemiology in sub-Saharan Africa are increasing. The current review assesses the level of environmental pollution by heavy metals in sub-Saharan Africa, and brings to the fore available evidence implicating such in the increasing cancer epidemiology in the sub-continent.

• Environmental Engineering Research
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• 제18권3호
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• pp.177-189
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• 2013

Studies were carried out on the speciation of heavy metals (Zn, Cu, Mn, Fe, Ni, Pb, Cd, and Cr) during rotary drum composting of water hyacinth (Eichhornia crassipes) for a period of 20 days. Five different proportions of cattle manure, water hyacinth and sawdust were prepared for composting. This study concluded that, rotary drum was very efficient for the degradation of organic matter as well as for the reduction of mobility and bioavailability of heavy metals during water hyacinth composting. The results from the sequential extraction procedure of heavy metals shows that rotary drum composting changed the distribution of five fractions of Zn, Cu, Mn, Fe, Ni, Pb, Cd, and Cr. The highest reduction in the bioavailability factors of Pb and Cd was observed during the process. The total concentration of Cu, Cr, and Cd was very low compared to the other metals (Zn, Mn, Fe, Ni, and Pb); however, the percentage of exchangeable and carbonate fractions of these metals was similar to other metals. These results confirmed that the bioavailability of metals does not depend on the total concentration of metals. From this study, it can be concluded that the addition of an appropriate proportion of cattle manure significantly reduced the mobile and easily available fractions (exchangeable and carbonate fractions) during water hyacinth composting in rotary drum.

• 한국환경과학회지
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• 제21권3호
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• pp.377-382
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• 2012

Recent research has demonstrated that treating poultry litter with alum (aluminum sulfate) and aluminum chloride can remove environmental threats (ammonia, soluble phosphorus and odor) posed by litter. However, scientific information available on heavy metal in poultry litter with liquid aluminum chloride is still lacked. The purpose of this study was to investigate the effects of applying liquid aluminum chloride to rice hulls on heavy metals and to provide basic information to producers. Six hundred 0-d-old broiler were assigned to 4 treatments (control, 100 g, 200 g and 300 g of liquid $AlCl_3$/kg of rice hulls, respectively) with 3 replicates of 50 birds. The experimental period lasted for 6 weeks. Liquid $AlCl_3$ was sprayed on the rice hulls surface using a small hand pump. Total Al contents increased (P<0.05) with the increasing levels of liquid $AlCl_3$ levels over time in comparison with control groups. Total Cu and Pb were lowered in all liquid $AlCl_3$ treatments compared with the controls during 6 weeks. Significant differences in all treatments were found for total Cu contents at 2, 3 and 5 weeks and total Pb at 0, 1, 2 and 3 weeks. Total Zn contents decreased with time when compared with controls. However, no significant differences in total Zn contents were observed among all treatments. In light of environmental managements, spraying liquid $AlCl_3$ to rice hulls indicated the significant advantages in reducing heavy metals as well as improving poultry industrial competitiveness.

• 한국환경농학회지
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• 제23권1호
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• pp.15-21
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• 2004

우리나라 중부지역에서 1998년 $3{\sim}5$월에 과수원 토양 164지점(경기 48, 강원 36, 충북 36, 충남 44지점)을 대상으로 표토($0{\sim}20\;cm$)와 심토($20{\sim}40\;cm$)로 나누어 채취하여 토양내 중금속함량과 분포특성, 총함량에 대한 침출액별 가용성 함량비율 및 토양 이화학성과의 관계를 비교 검토한 결과는 다음과 같다. 과수원 토양중 0.1N-HCl 침출성 평균함량은 Cd 0.080, Cu 4.23, Fb 3.42 mg/ks 1N-HCl 침출성 As 평균함량은 0.44 mg/kg, 중금속 총함량은 Zn 78.9, Ni 16.09 및 Hg 0.052 mg/kg 이었다. 과수원 토양내 중금속 평균함량은 우리나라 토양환경보전법의 토양오염 우려기준(Cd 1.5, Cu 50, Pb 100, Zn 300, Ni 40, Hg 4 mg/kg)과 비교하여 $1/2.5{\sim}1/76.9$ 수준으로 안전하였다. 토양의 중금속 총함량에 대한 침출액별 가용성 함량비율은 Cd $5.4{\sim}9.2$, Cu $27.9{\sim}47.8$, Pb $12.6{\sim}21.8$, Zn $15.8{\sim}20.3$, Ni $5.3{\sim}6.3$, Cr $0.7{\sim}3.6%$ 이었고, 특히 0.05 M-EDTA 침출성 Cu 및 Pb의 침출비율이 상대적으로 높게 나타났다. 토양내 Cd, Pb 및 Ni의 총함량은 모래함량과 부의상관, 미사와 점토함량과는 정의 상관을 보였다. 토양의 중금속 총함량에 대한 침출액별 가용성 함량비율은 점토함량과는 부의 상관을 보였으며, Zn과 Ni의 함량비율은 토양 pH값, 유기물 및 유효인산 함량과 정의 상관을 보였다. 이상의 결과에서 볼 때 과수원 토양의 중금속 함량은 토양환경보전법의 토양오염기준보다 매우 낮아 안전하였으나 영농활동에 의한 영향으로 볼 수 있는 농도수준이 검출된 일부 토양에서 조사되었다. 따라서 최근의 친환경농업 측면으로 볼 때 영농형태별 중금속의 분포 및 농업자재에 의한 농경지내 중금속 부하량에 근거하여 중금속 오염유무를 평가할 수 있는 판단기준에 대한 연구가 필요하다고 생각된다.

• 한국식품과학회지
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• 제42권4호
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• pp.502-507
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• 2010

본 연구에서는 시판중인 일부 채소류의 중금속 함량을 조사해 국외기준과 비교하고 그 안전성을 검증해보고자 하였다. 전국에서 재배되어 시중에서 유통되고 있는 채소류 15종 243건을 시료로 하였다. 시료의 분석방법은 습식분해법 중 microwave 법을 이용하였으며 납, 카드뮴, 비소, 크롬, 구리, 망간, 아연을 유도결합 플라즈마 분광기(inductively coupled plasma spectrometer, ICP)를 이용하여 분석하였다. 조사결과 채소류의 평균 함량(최소-최대함량, mg/kg)은 Pb, 0.0026(ND-0.0313); Cd, 0.0017(ND-0.0280), As, 0.0005(ND-0.0332); Cr, 0.0156(0.0010-0.1798); Cu, 0.3767(0.0556-1.3980); Mn, 3.0214(0.0182-26.4100); Zn, 3.5796(0.830-14.46)으로 나타났다. 본 연구를 통해 얻어진 결과들 중 납, 카드뮴, 비소는 기존 연구결과들과 비슷하거나 낮은 수준이었으며 크롬, 구리, 망간, 아연은 비슷한 수준으로 나타났다. 또한 조사한 품목의 주간 섭취량을 FAO/WHO에서 안전성 평가를 위해 설정한 PTWI와 PMTDI 기준과 비교한 결과 그 수준이 매우 낮아 우리나라에서 재배되는 이들 채소류로부터 섭취하는 중금속 양은 안전한 수준으로 판단되었다. 본 연구결과는 아직 세부기준이 설정되지 않는 채소류의 중금속 기준을 설정하는데 있어 참고 자료로 활용될 수 있을 것으로 기대된다.

• KSBB Journal
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• 제11권2호
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• pp.173-180
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• 1996

S. CereVlSWe를 이용하여 Pb 이온의 흡착 능력을 조사하였다. 살아있는 S. CereVlSWe 및 멸균된 S. cereVlswe 보다 건조분쇄 된 S. cerevisiae가 Pb 흡착 능력이 가장 좋았다. 통일의 중금속 농도에서 중금 속 단위 흡착량은 미생물 농도가 높아짐에 감소하였다. 살아있는 S. cereVlsiae의 흡착 능력 순서는 Pb > >Cu> Cd = Co>Cr > Zn = Ni순이었다. 중금속 흡 착에서 0.1 M NaOH로 24시간 전처리하여 흡착량을 1.5배 증가시킬 수 있었다. 0.1 M HCl 및 0.1 M $H_2S_O4$ 로 Pb이온을 효과적으로 탈착시킬 수 있었다. Pb 이온의 흡착평형은 Freundlich 흡착등온식과 Langmuir 흡착등온식으로 설명할 수 있었다.

• 한국유기농업학회지
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• 제9권1호
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• pp.61-73
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• 2001

This study was conducted to investigate the effect of sewage sludge application on the growth of chinese cabbage and the changes of chemical properties of soil. The experiment were set up with two different place and cultivated from Feb. 10 to June. 20 of 2000. Treatments are 0, 1.25, 2.5, 5, 10 and 20kg/3.3$\m^2$ of sewage sludge applicated into the soil and recorded the growth characteristics. Chemical properties of soil were also analysed before and after treatment. The application of the sewage sludge resulted in increasing the content of EC, cations exchange capacity, available phosphate and organic matter. And increased the growth characteristics in terms of the number of leaves, leaf area, fresh and dry weight regardless of crops experiments. Optimum amount of the sewage sludge depended on chemical properties of soil used. This results demonstrated that application of sewage sludge in the soil attribute to have play an important both improving soil chemical properties and promoting the crop growth. As lowering the soil pH(pH 6) heavy metal content increased compared with higher pH(pH 7). Feasibility was recognized in the application of sewage sludge as a fertilizer for the growth of chinese cabbage. Detrimental effects such as heavy metal in the soil and crop followed by the application of sewage sludge was not observed.

• 한국수산과학회지
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• 제38권3호
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• pp.153-157
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• 2005

The biosorption of Pb and Cr by Sargassum thunbergii was investigated in a batch conditions. The Pb and Cr uptake capacity of Sargassum thunbergii was 232.5 mg Pb/g biomass and 91.6 mg Cr/g biomass, respectively. An adsorption equilibria was reached within about 0.5 hr for both the Pb and the Cr. The adsorption parameters for both the Pb and the Cr were determined according to the Langmuir and Freundlich model. With increasing pH values, more negative sites are becoming available for the adsorption of Pb and Cr. The selectivity of mixture solution showed an uptake order of Pb>Cu>Cr>Cd. Pb and Cr adsorbed by S. thunbergii could be recovered ken 0.1 M HCl, 0.1 M $HNO_3$ and 0.1M EDTA by a desorption process, and the efficiency of Pb desorption was above $95.8\%$, whereas the efficiency of the Cr desorption was below $50.7\%$.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 추계학술발표강연 및 논문개요집
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• pp.93-93
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• 2003

Tungsten and tungsten heavy alloys have widespread application as radiation shielding devices and heavy duty electrical contacts. High density and good room temperature mechanical properties have generated interest in evaluating tungsten and tungsten alloys as kinetic energy penetrators against armor. Nowdays ultra fine-grained tungsten powders are in great interest because higly dense structures can be obtained at low temperature, pressure and lower sintering time. Several physical md chemical methods are available for the synthesis of nanometric metal Powders: ball milling, laser abalation, vapor condensation, chemical precipitation, metallic wire explosion i.e. However production rates of the above mentioned methods are low and further efforts are needed to find out large-scale synthesis methods. From this point of view solid state combustion method ( known as SHS) represents undoubted interest.