• 한국지하수토양환경학회지:지하수토양환경
• /
• 제23권1호
• /
• pp.54-62
• /
• 2018

This paper is aimed at source tracking of soil heavy metal contamination at a site established by reusing construction wastes. The soil heavy metal concentration at the study site peaked at a depth range of 5-10 m. Column studies were conducted to investigate the possibility of the contamination scenario of infiltration of stormwater carrying heavy metals of ground origin followed by selective heavy metal accumulation at the 5-10 m depth range. Almost all amount of lead, zinc, cadmium, and nickel introduced to the columns each packed with 0-5 m or 5-10 m field soil were accumulated in the column. The very poor heavy metal mobility in spite of the weak association of the heavy metals with the soil (characterized by a sequential extraction procedure) can be attributed to the high pH (10-11) of the construction wastes. From the results, the heavy metal contamination of the subsurface soil by an external heavy metal source was determined to be very unlikely at the study site. The column study applied in the current study is expected to be a useful methodology to present direct evidence of the contaminant source tracking at soil contamination sites.

• 한국토양비료학회지
• /
• 제49권5호
• /
• pp.524-530
• /
• 2016

Agricultural soils near or around industrial complexes can contain a certain amount of heavy metals that readily enter the food chain and negatively affect human health. Therefore, we conducted the study to investigate the distribution of selected heavy metals, including arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni), lead (Pb), mercury (Hg), and zinc (Zn), in farm-land soils around fifteen industrial complexes in the southwestern provinces, Korea. The concentrations of heavy metals in the soil samples were determined by the pseudo-total aqua regia (3 HCl : $1HNO_3$) digestion procedure. The heavy metal concentrations in most soils examined did not exceed the levels of Soil Contamination Warning Standard (SCWS) for agricultural lands (Region 1) presented in Soil Environment Conservation Law (SECL) established by Ministry of Environment (MOE), Korea. However, only one sampling site showed higher As amount ($27.1mg\;kg^{-1}$) than the SCWS level of As ($25mg\;kg^{-1}$). Pollution index (PI) for heavy metals did not exceed 1.0. The PI values were significantly positively correlated (p < 0.01) with the heavy metal concentrations. In particular, the values of correlation coefficient between the Cd and Pb concentrations and the PI values were higher than those estimated from other combinations, and thus the amounts of Cd and Pb in the agricultural soils highly affected the PI values for the heavy metals.

• 농촌의학ㆍ지역보건
• /
• 제21권1호
• /
• pp.85-95
• /
• 1996

울산 연안의 공업단지를 비철금속 공업을 주로 하는 온산공단과 자동차 및 조선업을 주로 하는 미포공단, 석유화학 공업을 주로 하는 석유화학공단으로 나누어, 이러한 공업단지별로 해수 및 홍합중의 중금속 함량을 측정하고 이에 따른 홍합의 각 중금속 생물농축계수를 산정해 보았다. 시료는 1995년 4월 6일에 채취하였고, 분석방법은 원자흡광광도법에 따랐다. 해수중의 납 함량은 석유화학공단 해역 (1.8${\pm}$2.4ppb)이 가장 높았고, 홍합중의 납 함량도 석유화학공단 해역(0.800${\pm}$0.418ppm)이 가장 높았다. 해수중의 카드뮴 함량은 미포공단해역(1.3${\pm}$1.4ppb)이 가장 높았고, 홍합중의 카드뮴 함량은 석유화학공단 해역(0.282${\pm}$0.07ppm) 이 가장 높았다. 해수중의 수은은 전 해역에서 검출되지 않았고, 홍합중의 수은은 석유화학공단 해역(0.025${\pm}$0.0011ppm)이 가장 높았다. 해수중의 구리 함량은 미포공단 해역이 가장 높았고(0.5${\pm}$0.9ppb), 홍합도 미포공단 해역 (2.132${\pm}$0.526ppm)이 가장 높았다. 해수중의 망간 함량은 미포공단과 석유화학공단 해역이 비슷한 수준요도 나타났고(2.7${\pm}$2.1ppb, 2.4${\pm}$1.5ppb), 홍합에서는 석유화학공단 해역이 가장 높게 나타났다(3.212${\pm}$2.445ppm). 아연함량은 해수와 홍합 모두 미포공단 해역에서 가장 높게(55.6${\pm}$9.4ppb, 19.560${\pm}$9.979ppm) 나타났다. 울산연안 해역에 서식하는 홍합의 중금속 농축계수는 납, 카드뮴, 망간의 경우 평균 1,070배, 1,370배, 1,300배로 비슷하게 나타났고, 수은이 가장 낮은 80배, 구리는 6,940배로 가장 높은 농축률을 보였다. 울산연안 해수의 중금속 농도는 인근 공단별로 차이를 나타내고 있었으며, 카드뮴, 구리, 망간, 아연은 미포공단이 가장 높았고, 납은 석유 화학공단해역이 가장 높았다. 납, 구리, 아연의 경우 해수중의 농도가 높은 지역에서는 홍합중의 농도도 높게 나타났다. 그러나 카드뮴 경우 해수중의 농도는 미포공단에서 가장 높았으나 홍합중의 농도는 석유화학 공단에서 가장 높게 나타나 차이를 보였다. 이상의 결과로 볼 때, 연안 오염의 동태를 파악하기 위해서는 해수보다는 홍합과 간은 부착 패류를 지표종으로 설정하는 것이 타당한 것으로 보인다.

• 한국토양비료학회지
• /
• 제49권5호
• /
• pp.589-597
• /
• 2016

There are a number of industrial complexes which could be a source of heavy metal (loid)s contamination of arable soil in Gyeongnam province of South Korea. Heavy metal (loid)s accumulation of plant is more related to the concentration of plant available heavy metal (loid)s in arable soil than that of total heavy metal (loid)s. The objectives of this study were 1) to examine heavy metal concentrations in soils located near industrial complexes in Gyeongnam province and 2) to determine the relationship between concentration of plant available heavy metal (loid)s and chemical properties of soil. Soil samples were collected from 85 sites of arable lands nearby 7 industrial complexes in Gyeongnam province. Total heavy metal (loid)s concentration, available heavy metal (loid)s concentration, and chemical properties of collected soils were measured. The mean concentrations of arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) in the soils were $5.8mg\;kg^{-1}$, $1.3mg\;kg^{-1}$, $0.03mg\;kg^{-1}$, $51.5mg\;kg^{-1}$, and $68.7mg\;kg^{-1}$, respectively. Total concentration of Cd and Zn in arable soil located near ${\nabla}{\nabla}$ industrial complex exceeded the warning criteria ($4mg\;kg^{-1}$ and $300mg\;kg^{-1}$ for Cd and Zn, respectively) as described by in the soil environmental conservation Act of Korea. The concentration of plant available heavy metal (loid)s was negatively related to the soil pH and available Pb and Zn concentrations had relatively high correlation coefficient when compared with other heavy metal (loid)s. The concentration of plant available Pb and Zn was negatively related to that of organic matter (OM). Based on the above results, it might be a good soil management to control pH and OM concentration with soil amendments such as lime and compost to reduce phytoavailability of heavy metal (loid)s in arable soil located near industrial complex.

• 분석과학
• /
• 제9권4호
• /
• pp.336-344
• /
• 1996

뇨시료 중 혼적량의 코발트, 구리, 니켈, 카드뮴, 납 및 아연을 흑연로 원자흡수분광 광도법으로 정량하기 위한 dithizone이 포함된 chloroform으로의 용매추출에 관하여 연구하였다. 실험조건인 시료의 전처리 과정, 추출용액의 pH, 킬레이트제인 dithizone의 농도, 역추출할 때 사용하는 산의 종류와 농도에 관하여 최적화하였다. 유기물의 방해를 제거하고자 뇨시료 100.0mL에 진한 질산 30mL를 가하고 30% 과산화수소 50mL를 5.0mL씩 단계적으로 가하면서 가열하여 유기물질을 분해하였다. 삭힌 뇨시료를 100mL로 만들어 분별 깔때기에 넣고 시판용 완충용액으로 pH가 8이 되게 조절한 다음 0.1% dithizone을 포함하는 chloroform 15.0mL를 가했다. 진탕기(shaker)를 이용하여 90분 동안 흔들어 준 후 상분리시켜 용매층을 분리하였다. 카드뮴, 납, 아연은 0.2M 질산용액 10.0mL로 역추출하여 직접 정량하였고, 이런 조건으로 역추출되지 않은 코발트, 구리, 니켈은 유기 용매를 증발 건고시킨 다음 잔류물을 $HNO_3$ $H_2O_2$로 녹이고, 정확히 10.0mL가 되게 탈염수로 묽혀서 정량하였다. 최적의 추출조건을 찾기 위하여 인공 뇨시료를 제조하여 검토하였고, 얻은 최적조건으로 검정곡선을 작성하였다. 삭힌 각 시료에 일정량 첨가된 원소를 정량하여 얻은 회수율은 77 내지 109%였고, 검출한계는 Cd(II) 0.09, Pb(II) 0.59, Zn(II) 0.18, Co(II) 0.24, Cu(II) 1.3, Ni(II) 1.7ng/mL였다. 이로써 본 방법이 과량의 유기물과 알칼리 및 알칼리 토금속이 포함된 뇨시료에서 혼적량 원소들을 정량적으로 분리 분석할 수 있음 을 알았다.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
• /
• pp.65-65
• /
• 2015

In this talk, I will introduce two topics. The first topic is the polymer light emitting diodes (PLEDs) using graphene oxide quantum dots as emissive center. More specifically, the energy transfer mechanism as well as the origin of white electroluminescence in the PLED were investigated. The second topic is the facile synthesis of eco-friendly III-V colloidal quantum dots and their application to light emitting diodes. Polymer (organic) light emitting diodes (PLEDs) using quantum dots (QDs) as emissive materials have received much attention as promising components for next-generation displays. Despite their outstanding properties, toxic and hazardous nature of QDs is a serious impediment to their use in future eco-friendly opto-electronic device applications. Owing to the desires to develop new types of nanomaterial without health and environmental effects but with strong opto-electrical properties similar to QDs, graphene quantum dots (GQDs) have attracted great interest as promising luminophores. However, the origin of electroluminescence (EL) from GQDs incorporated PLEDs is unclear. Herein, we synthesized graphene oxide quantum dots (GOQDs) using a modified hydrothermal deoxidization method and characterized the PLED performance using GOQDs blended poly(N-vinyl carbazole) (PVK) as emissive layer. Simple device structure was used to reveal the origin of EL by excluding the contribution of and contamination from other layers. The energy transfer and interaction between the PVK host and GOQDs guest were investigated using steady-state PL, time-correlated single photon counting (TCSPC) and density functional theory (DFT) calculations. Experiments revealed that white EL emission from the PLED originated from the hybridized GOQD-PVK complex emission with the contributions from the individual GOQDs and PVK emissions. (Sci Rep., 5, 11032, 2015). New III-V colloidal quantum dots (CQDs) were synthesized using the hot-injection method and the QD-light emitting diodes (QLEDs) using these CQDs as emissive layer were demonstrated for the first time. The band gaps of the III-V CQDs were varied by varying the metal fraction and by particle size control. The X-ray absorption fine structure (XAFS) results show that the crystal states of the III-V CQDs consist of multi-phase states; multi-peak photoluminescence (PL) resulted from these multi-phase states. Inverted structured QLED shows green EL emission and a maximum luminance of ~45 cd/m2. This result shows that III-V CQDs can be a good substitute for conventional cadmium-containing CQDs in various opto-electronic applications, e.g., eco-friendly displays. (Un-published results).

• 한국토양비료학회지
• /
• 제47권1호
• /
• pp.41-47
• /
• 2014

Agricultural soils surrounding mine areas in South Korea are often contaminated with multiple metals such as Cd, Pb and Zn. It poses potential risks to plants, soil organisms, groundwater, and eventually human health. The aim of this study was to examine the changes in phytoavailability of Cd, Cu, Pb and Zn after application with calcined eggshell (CES; 0, 1, 3, and 5% W/W) in an agricultural soil contaminated by mine tailings. The contents of Cd, Cu, Pb and Zn in soils were 8.79, 65.4, 1602, and $692mgkg^{-1}$ (aqua regia dissolution), respectively. The experiments were conducted with lettuce (Lactuca sativa L. var. longifolia) grown under greenhouse conditions during a 30-d period. $NH_4NO_3$ solution was used to examine the mobile fraction of these metals in soil. The application of CES dramatically increased soil pH and inorganic carbon content in soil due to CaO and $CaCO_3$ of CES. The increased soil pH decreased the mobile fraction of Cd, Pb, Zn: from 3.49 to < $0.01mgkg^{-1}$ for Cd, from 79.4 to $1.75mgkg^{-1}$ for Pb, and from 29.6 to $1.13mgkg^{-1}$ for Zn with increasing treatment of CES from 0 to 5%. In contrast, the mobile fraction of Cu was increased from 0.05 to $3.08mgkg^{-1}$, probably due to the formation of soluble $CuCO_3{^0}$ and Cu-organic complex. This changes in the mobile fraction resulted in a diminished uptake of Cd, Pb and Zn by lettuce and an increased uptake of Cu: from 4.19 to < $0.001mgkg^{-1}$ dry weight (DW) for Cd, from 0.78 to < $0.001mgkg^{-1}$ DW for Pb, and from 133 to $50.0mgkg^{-1}$ DW for Zn and conversely, from 3.79 up to $8.21kg^{-1}$ DW for Cu. The increased contents of Cu in lettuce shoots did not exceed the toxic level of $>25mgkg^{-1}$ DW. The mobile contents of these metals in soils showed a strong relationship with their contents in plant roots and shoots. These results showed that CES effectively reduced the phytoavailability of Cd, Pb, and Zn to lettuce but elevated that of Cu in consequence of the changed binding forms of Cd, Cu, Pb, and Zn in soils. Based on these conclusions, CES can be used as an effective immobilization agent for Cd, Pb and Zn in contaminated soils. However, the CES should be applied in restricted doses due to too high increased pH in soils.

• 대한화학회지
• /
• 제40권12호
• /
• pp.724-732
• /
• 1996

물시료중 흔적량 비스무트, 카드뮴, 납, 코발트를 Cu(II)-pyrrolidinedithiocabamate 착물로 공침부선시켜 분리 정량하는 방법에 관하여 연구하였다. 부선조건인 시료용액의 pH, 공침제로 이용되는 구리의 양, 착화제인 APDC의 양, 저어주는 시간, 계면활성제 등을 조사하여 최적화시켰다. 흔적량 분석원소가 포함된 시료용액 1.0 L에 공침제 이온인 1, 000.mu.g/mL Cu(II) 표준용액을 3mL가하고, 자석젓개로 저으면서 질산 용액으로 pH2.5로 조절하였다. 2.0% ammonium pyrroildinedithiocarbamate(APDC) 용액을 첨가하여 Cu(II)-PDC 착물을 침전시켜 분석원소를 공침시켰다. 여기에 계면활성제인 0.2% sodium laurl sulfate 용액을 가하고, 다공성 유리판을 통해 질소를 불어서 침전을 띄웠다. 표면에 뜬 침전을 포집한 다음, 걸러서 진한 질산으로 녹여 탈염수로 25.0mL가 되게 하였고, 흑연로 원자흡수 분광광도법으로 농축된 분석원소를 정량하였다. 본 방법을 네가지 물시료에 적용하여 흔적량 원소를 동시에 농축 정량하였고, 일정량의 분석원소를 동일 시료에 첨가하여 정량한 회수율 90-120%로서 여기서 제시한 분석법이 흔적량 분석에서 정량적임을 알 수 있었다.

• 자원리싸이클링
• /
• 제26권4호
• /
• pp.50-55
• /
• 2017

복잡한 모체를 갖는 시료에 존재하는 미량의 원소들은 모체방해효과로 인하여 분석이 어렵다. 따라서 시료모체로부터 미량의 원소들을 분리해서 분석할 수 있다면 그 방해 요인을 줄일 수 있어 분석에 많은 도움이 된다. 시료모체와 미량의 원소들을 분리하기 위하여 인듐 수산화물($In(OH)_3$)을 이용하여 시료 내에 존재하는 미량의 원소들을 공동침전시킴으로서 분석물질을 분리시킨 후에 유도 결합 플라즈마-원자 방출 분광법을 이용하여 분석하는 방법에 대한 연구를 하였다. 이 연구에서는 공동침전의 발생과 회수율을 높일 수 있는 최적의 조건을 실험을 통해 설정하였다. 공동침전물을 석영섬유필터를 사용하여 걸러내고, 공침이 발생하는 시료의 pH를 9.5로 조정하였다. 또한 필터의 침전물을 ICP-AES로 측정하기 위해 질산 30% 용액에 1분 동안 담궈 침전물을 녹였고, 침전물이 녹은 질산용액은 온도변화 없이 농축을 진행하는 최적의 조건을 설정하였다. 이 최적조건을 소금시료에 적용하여 분석한 결과, 신안 증도에서의 소금에서는 중금속이 거의 검출 되지 않았지만 전남 영광 소금의 경우 카드뮴을 제외하고 여러개의 중금속이 미량 검출되었다.

• 한국토양비료학회지
• /
• 제48권5호
• /
• pp.332-339
• /
• 2015

The objective of this study was to evaluate the effectiveness of different biochars on the removal of heavy metals from aqueous media. The experiment was carried out in aqueous solutions containing $200mg\;CdL^{-1}$ or $200mg\;PbL^{-1}$ using two different biochars derived from soybean stover and orange peel (20 mg Cd or $Pbg^{-1}$ biochar). After shaking for 24 hours, biochars were filtered out, and Cd and Pb in the filtrate were analyzed by flame atomic absorption spectrophotometer (FAAS). In order to provide information regarding metal binding strength on biochars, sequential extraction was performed by modified SM&T (formerly BCR). The results showed that 70~100% of initially added Cd and Pb was adsorbed on biochars and removed from aqueous solution. The removal rate of Pb (95%, 100%) was higher than that of Cd (70%, 91%). In the case of Cd, orange peel derived biochar (91%) showed higher adsorption rate than soybean stover derived biochar (70%). Cd was adsorbed on the biochar mainly in exchangeable and carbonates fraction (1st phase). In contrast, Pb was adsorbed on it mainly in the form of Fe-Mn oxides and residual fraction (2nd and 4th phase). The existence of Cd and Pb as a form of surface-precipitated complex was also observed on the surfaces of biochars detected by field emission scanning electron microscope (FESEM) and energy dispersive X-ray spectrometer (EDAX).