• The Plant Pathology Journal
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• 제32권4호
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• pp.329-339
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• 2016

The short-term effects of low-level contamination by heavy metals (As, Cd, Cu, and Pb) on the soil health were examined by analyzing soil nematode community in soils planted with tomatoes. For this, the soils were irrigated with five metal concentrations ([1, 1/4, $1/4^2$, $1/4^3$, and 0] ${\times}$ maximum concentrations [MC] detected in irrigation waters near abandoned mine sites) for 18 weeks. Heavy metal concentrations were significantly increased in soils irrigated with MC of heavy metals, among which As and Cu exceeded the maximum heavy metal residue contents of soil approved in Korea. In no heavy metal treatment controls, nematode abundances for all trophic groups (except omnivorous-predatory nematodes [OP]) and colonizer-persister (cp) values (except cp-4-5) were significantly increased, and all maturity indices (except maturity index [MI] of plant-parasitic nematodes) and structure index (SI) were significantly decreased, suggesting the soil environments might have been disturbed during 18 weeks of tomato growth. There were no concentration-dependent significant decreases in richness, abundance, or MI for most heavy metals; however, their significant decreases occurred in abundance and richness of OP and cp-4, MI2-5 (excluding cp-1) and SI, indicating disturbed soil ecosystems, at the higher concentrations (MC and MC/4) of Pb that had the most significant negative correlation coefficients for heavy metal concentrations and nematode community among the heavy metals. Therefore, the short-term effects of low-level heavy metal contamination on soil health can be analyzed by nematode community structures before the appearance of plant damages caused by the abiotic agents, heavy metals.

• 한국환경보건학회지
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• 제43권5호
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• pp.393-400
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• 2017

This study was investigated on pH, heavy metals, oils and solvents in 34 surface soil samples and the samples are collected at two times for 17 farmland sites around 7 industrial areas in Northern Gyeonggi Province. As a result of pH for soil contamination monitoring network, the range of pH showed 4.4~8.4 and average was 6.3. The range of pH for Agricultural land around industrial area was 6.7~7.5 and average indicated 7.1 that mostly showed neutral condition in this area. he average concentrations of Cu, Pb, Ni, As and $Cr^{6+}$ are lower than Korea soil contamination worrisome levels at region 1 and the mean levels of farmland from the soil quality monitoring network. The average concentrations of Zn, Cd and Hg didn't exceed the soil contamination worrisome levels at region 1 but slightly higher than the mean levels of farmland from the soil quality monitoring network. The heavy metal levels of all samples are within Korea soil contamination worrisome levels at region 1. The results showed that the detected heavy metal concentrations ranged from N.D. to ~32.7% of Korea soil contamination worrisome levels at region 1. BTEX, TPH, TCE and PCE were not detected in all samples and thus the farmland around the industrial areas were free from oils and solvents contamination.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.271-274
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• 2002

Heavy metal concentrations of roadside soils around interchanges were found to decrease as Zn)Cu>Pb and be lower than the legal guideline levels. The concentrations of Cu, Pb and Zn in roadside soils around Kyeong-bu highway interchanges were 1.3 to 1.5 times higher those around Yeong-dong highway interchanges. Difference of heavy metal concentrations in soils seems to be caused by difference of traffic volume between Kyeong-bu and Yeong-dong highway interchanges. This means that contamination of interchange roadside soils mainly depends on traffic volume.

• Applied Biological Chemistry
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• 제45권2호
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• pp.92-96
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• 2002

서울시 주요 도로변 토양의 현재 오염정도와 앞으로 있을 오염에 대한 비교 자료를 구축할 목적으로 서울시의 25개 구 중 5개 구(강동구, 광진구, 노원구, 서대문구, 성동구)를 선정하여 토양 오염도를 조사하였다. 시료의 채취는 각 구의 주요 도로변에서 50지점을 선정하여 실시하였으며, 가로수 식수대 내의 표토(1-5rm)와 심토(20-50 cm)에서 시료를 채취하였다. 채취된 총 시료는 표토와 심토 각각 250점이었으며, 채취된 시료를 풍건시킨 후 2mm체로 쳐서 분석에 이용하였다. 분석항목은 pH를 비롯한 토양의 이화학적 특성과 중금속(Cd, Cu, Pb, Zn) 이었다. 조사 결과 토성은 사양토와 양질사토가 주를 이루었다. 토양 pH는 4.5-10.0의 범위에서 표토와 심토의 평균이 각각 7.52, 7.50으로 약알칼리성을 나타내어 서울 주변 산림지대의 pH값보다 높은 수치를 보였다. 검출된 중금속 농도의 범위는 Cd, Cu, Pb, Zn에 대하여 각각 $0.01{\sim}1.19$, N.D.(not detected)${\sim}234.45$, $N.D.{\sim}381.23$, $2.97{\sim}737.59\;mg\;kg^{-1}$이었다. 각 구에서 측정된 중금속 농도 평균의 대부분은 토양환경보전법상 우려기준을 초과하지는 않았으나 서울시 근교 도시림의 중금속 함량보다는 상당히 높은 값을 나타내었다. 그리고 일부 조사지점에서 토양환경보전법상의 우려기준을 초과하는 지점에 있었으며, 특히 성동구의 Cu 평균 함량은 토양환경보전법상의 우려기준을 초과하여 정밀조사 및 오염 확산 방지를 위한 조치가 필요할 것으로 생각된다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제15권3호
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• pp.1-6
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• 2010

This study investigated the change of metal contamination levels according to amendment of enforcement regulation of the Soil Environmental Conservation Act in Korea. As an analytical result of 87 samples in abandoned metallic mine area, the extracted amount of As, Pb and Cu with aqua regia was 4.3~29.6 times higher than that with hydrochloric acid extraction and the number of samples, which contamination levels were found to exceed soil contamination standards, was also increased. On the other hand, in case of Cd, Zn, and Ni, the number of samples, which contamination levels were found to exceed soil contamination standards, was decreased or similar. These results can be used as a preliminary material in comparison between the soil pollution data accumulated previously and the data obtained by the revised standard method for the examination of soil pollution.

• 한국재료학회지
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• 제14권8호
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• pp.552-557
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• 2004

Thin Ni-B films, 1 ${\mu}m$ thick, were electrolessly deposited on Cu bus electrode fabricated by electro deposition. The purpose of these films is to encapsulate Cu electrodes for preventing Cu oxidation and to serve as a diffusion barrier against copper contamination of dielectric layer in AC-plasma display panel. The layers were heat treated at $580^{\circ}C$(baking temperature of dielectric layer) with and without pre-annealing at $300^{\circ}C$($Ni_{3}B$ formation temperature) for 30 minutes. In the layer with pre-annealing, amount of Cu diffusion was lower about 5 times than that in the layer without pre-annealing. The difference of Cu concentration could be attributed to Cu diffusion before $Ni_{3}B$ formation at grain boundaries. However, the diffusion behavior of the layer with pre-annealing was similar to that of the layer without pre-annealing after $Ni_{3}B$ formation. With increasing annealing time, Cu concentration of both layers increased due to grain growth.

• 한국재료학회지
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• 제16권2호
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• pp.80-84
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• 2006

The removal efficiency of Cu and Fe contaminants on the silicon wafer surface was examined to investigate the effect of cleaning solutions on the behavior of metallic impurities. Silicon wafers were intentionally contaminated with Cu and Fe solutions by spin coating and cleaned in different types of cleaning solutions based on $NH_4OH/H_2O_2/H_2O\;(SC1),\;H_2O_2/HCl/H_2O$ (SC2), and/or HCl/$H_2O$ (m-SC2) mixtures. The concentration of metallic contaminants on the silicon wafer surface before and after cleaning was analyzed by vapor phase decomposition/inductively coupled plasma-mass spectrometry (VPD/ICP-MS). Cu ions were effectively removed both in alkali (SC1) and in acid (SC2) based solutions. When $H_2O_2$ was not added to SC2 solution like m-SC2, the removal efficiency of Cu impurities was decreased drastically. The efficiency of Cu ions in SC1 was not changed by increasing cleaning temperature. Fe ions were soluble only in acid solution like SC2 or m-SC2 solution. The removal efficiencies of Fe ions in acid solutions were enhanced by increasing cleaning temperature. It is found that the behavior of metallic contaminants as Cu and Fe from silicon surfaces in cleaning solutions could be explained in terms of Pourbaix diagram.

• 대한임상검사과학회지
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• 제41권1호
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• pp.31-36
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• 2009

The exposure of human beings to toxic trace metals (Cu, Zn) continues to be an important public health issue and concern. This study was conducted to assess the exposure to trace metals (Cu, Zn) in the general Korean population by inductively coupled plasma mass spectrometry (ICP-MS) and Atomic absorption spectrometry (AAS). Serum samples were obtained from 40 healthy volunteers. Specimens were collected in special container and we applied sample processing to minimize contamination. We used ICP-MS and AAS to analyze simultaneously the concentration of metals including copper, zinc. Distribution of trace metal levels in the general healthy population showed lower values. The results in this study can provide background data for clinical studies associated with trace metal exposure in the korean population.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.1292-1295
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• 2004

본 연구는 Cu CMP공정 중 알루미나 연마입자의 wafer 표면에서의 점착과 오염을 AFM (Atomic Force Microscopy)을 사용하여 슬러리내에서 점착력 측정과 실제 연마 후 wafer 표면의 오염을 실험적으로 비교 평가하였다. 연마입자의 adhesionn force 측정에 있어서도 역시 wafer들의 zetapotential 결과와 잘 일치하였으며, 모든 wafer 종류에 관계없이, 산성 영역에서 염기성영역의 슬러리가 적용됨에 따라 adhesion force가 작아짐을 확인할 수 있었다. 특히 FSG wafer의 zetapotential 결과는 비록 산성 분위기에서는 양성 전하값을 나타내었으나, 염기성 분위기의 pH에서는 급격하게 음성 전하값을 나타내었고, 이는 adhesionn force결과와 FESEM 결과와 잘 일치하였다.

• 대한방사선치료학회지
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• 제8권1호
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• pp.41-54
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• 1996

The secondary electrons developed by interaction between primary beam and a tray mounted for blocks in Megavoltage irradiation result in excess soft radiation dose to the surface layer. To reduce this electron contamination, electron filters have been used to be attached under a tray. Various filters with Cu and Al plates in six different thickness and Cu/Al combined plates in 3 different thickness were tested to measure the reduction rate of secondary electron contamination to the surface layer. The measurement to find optimal filter was performed on 6MV linear accelerator in $10 cm{\times}10 cm$ field size and fixed 78.5cm source to measurement points distance from surface to maximum build up point in 2mm intervals. The result was analyzed as the ratio of measured doses with using filters, to standard doses of measured open beam. The result of this study was fellowing : 1. The contaminated low energy radiation were mainly produced by blocking tray. 2. The surface absorbed dose was slowly increased by increasing irradiation field size but rapidly increased at field size above $15cm{\times}15cm$. 3. Al plate upto 2.5mm thickness used as a filter was found to be inadequate due to the failure of reduction of the surface absorbed dose below doses of the under surface upto the maximal build up. Cu 0.5mm plate and Cu 0.28mm/A1 1.5mm compound plate were found to be optimal filters. 4. By using these 2 filters, the absorbed dose to the surface were effectively reduced $5.5\%$ in field size $4cm{\times}4cm,\;11.3\%$ in field size $10cm{\times}10cm,\;22.3\%$ in field size $25cm{\times}25cm$. 5. In field size $10cm{\times}10cm$, the absorbed dose to the surface of irradiation was reduced by setting TSD 20cm at least,. but effective and enough dose reduction could be achieved by setting TSD 30cm as 2 optimal filters used. 6. More surface dose absorbed at TSD less than 7.4cm with a tray and filters together indicated that soft radiation was also developed by filters. 7. The variation of PDD by the different size of irradiation field was minimal as 2 optimal filters used. There was also not different in variation of PDD according to using any of two different filters. 8. PDD was not effected either by various TSD or by using the different filter among two.