• 청정기술
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• 제23권1호
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• pp.27-33
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• 2017

본 연구에서는 중금속 7종(Cu, Cd, Cr, As(III), As(V), Zn, Ni) 및 나노입자 5종(CuO, ZnO, NiO, $TiO_2$, $Fe_2O_3$)에 대한 독성을 수계 대표 생물종인 녹조류 Chlorella vulgaris를 이용한 생물검정법으로 평가하였다. 조류에 미치는 영향은 흡광도, 클로로필 및 개체수 측정에 대한 결과를 통합하여 평가하였다. 중금속의 통합결과독성($TEC_{50}$) 순서는 Cr ($0.7mgL^{-1}$) > Cu ($1.7mgL^{-1}$) > Cd ($3.2mgL^{-1}$) > Zn ($3.9mgL^{-1}$) > Ni ($13.2mgL^{-1}$) > As(III) ($17.8mgL^{-1}$) ${\gg}$ As(V) (> $1000mgL^{-1}$)로 나타났다. 중금속은 측정종말점에 따라 일부 상이한 민감도와 독성이 조사되었다. 나노입자의 독성($TEC_{50}$) 순서는 ZnO ($2.4mgL^{-1}$) > NiO ($21.1mgL^{-1}$) > CuO ($36.6mgL^{-1}$) > $TiO_2$ ($62.5mgL^{-1}$) > $Fe_2O_3$ ($82.7mgL^{-1}$)로 나타났다. 나노입자는 측정종말점간에 비슷한 민감도와 독성을 보였다. 따라서 오염물의 독성을 평가하기 위해서 단일 방법에 의한 결과보다는 다양한 측정종말점의 통합결과에 근거한 접근이 적절할 것이다.

• 청정기술
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• 제24권4호
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• pp.293-300
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• 2018

설파메톡사졸(sulfamethoxazole, SMX)은 박테리아 치료를 위해 사람과 동물에게 널리 사용되어 온 설파아미드계열의 합성 항생제이다. 이들 대부분은 난분해성 물질로서 분해되지 않고 환경생태계에 노출되어 심각한 환경문제를 일으키게 된다. 본 연구에서는 난분해성 SMX를 분해하기 위하여 $Cu/Al_2O_3$ 촉매를 이용한 촉매습식과산화(catalytic wet peroxide oxidation, CWPO) 공정을 수행하였고, SMX를 완전히 분해하기 위한 최적의 온도, 촉매 주입량, 과산화수소($H_2O_2$)의 농도 등을 조사하였다. 1기압, $40^{\circ}C$에서 $H_2O_2$ 0.79 mM과 6 g의 10 wt% $Cu/Al_2O_3$ 촉매를 사용하여 20분 이내에 SMX가 완전히 분해되는 것으로 관찰되었다. 그러나 SMX는 완전히 무기화 되지 못하고, 중간생성물인 hydroylated-SMX, sulfanilic acid, 4-aminobenzenesulfinic acid, nitrobenzene을 거쳐 유기산으로 분해된 후 최종적으로 무기화 되었다. 이들 중간생성물의 거동을 파악하여 SMX의 분해 반응경로를 예측하였고 불균일 촉매의 내구성을 알아보기 위하여 10 wt% $Cu/Al_2O_3$ 촉매를 연속적으로 재사용 하여 SMX 분해율을 조사하였다. SMX의 분해율은 촉매를 5회 이상 재 사용하였을 때 다소 낮아졌지만 촉매의 활성도는 전반적으로 매우 안정적이었다.

• 자원환경지질
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• 제47권4호
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• pp.405-420
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• 2014

도심환경의 인위적 오염원에 의한 토양오염과 대기오염의 특성을 파악하기 위하여 서울지역 가로수의 플라타너스 잎과 토양을 격자형으로 52개의 지역에서 시료채취 및 중금속원소 함량을 측정하였다. 비교 대조를 위하여 비교적 오염이 적을 것으로 예상되는 충청남도 예산에 전원지역에서 2개 지점의 시료를 분석하였다. 서울시 토양 내 중금속 함량을 지역별로 측정한 결과, Cd, Co, Cr, Ni은 산업지역에서, Cu, Zn, Pb는 교통량 밀집지역에서 높았고, 도심 내 전원지역은 비교 대조지역보다 높은 중금속 함량을 보였다. 플라타너스 잎의 세척 전과 후의 차이는 Cd, Cu, Pb, Zn가 교통량 밀집지역에서 높았다. 토양은 Cd-Co, Cr-Ni, Cu-Zn, Pb-Zn는 상관계수 값이 0.8이상으로 양의 상관성을 보여 이들 원소간의 배출원은 유사하고, 플라타너스 잎은 Pb-Cu, Cu-Zn 원소간 상관성이 높았다. 플라타너스 잎의 중금속 조성이 토양으로부터 기인되는지를 확인하기 위해 토양과 세척한 잎과의 관계를 분석한 결과, Cr, Cu, Pb, Zn는 양의 상관성을 보였고, 반면 Cd, Co, Fe, Mn, Ni은 이들의 상관성이 낮은 것으로 보여 이들 원소들은 대기로부터 기인된 것으로 생각된다. 서울지역의 중금속 원소 분산을 등함량도의 원소별 패턴을 분석한 결과, 토양은 산업지역에서 Ni, Cr원소와 교통량 밀집지역에서 Cd, Cu, Zn원소의 오염도가 크고, 세척하지 않은 잎에 대한 Cd-Pb, Cu-Zn의 오염양상이 유사한 것으로 나타났다. 대기 중 부유된 원소별 부화지수 값을 예측을 위해 가로수 잎의 원소별 부화지수 값을 분석한 결과, Cu, Zn, Pb, Mn, Co, Ni, Cd, Cr 순으로 높았으며, 특히 서울지역에서는 Cu, Zn, Pb, Mn 으로 인한 오염이 심각한 것으로 판단된다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권6호
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• pp.111-116
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• 2015

The soil sample obtained from shooting area contaminated with Pb, Cu, and Zn was investigated to determine the chemical forms of heavy metals with Tessier’s sequential extraction method, which is constituted of five fractions such as ‘exchangeable’, ‘bound to carbonate’, ‘bound to oxide’, ‘bound to organic matter’, and residual fractions. The amount of organic matter was measured by loss on ignition (LOI) and then the results of ‘bound to organic matter’ and LOI were compared. The sequential extraction results show that 4.7%-45% of Pb, 6.2%-25.9% of Cu and 3.9%-15.3% of Zn belong to the ‘bound to organic matter’ fraction, but LOI result shows that only 1.0%-2.8% of organic matter exists in the soil sample. In heavy medium separation tests, because Pb and Cu extracted in ‘bound to organic matter’ and residual fractions were removed, the heavy metals in the fractions would exist as heavier forms. These results suggest that the part of heavy metal extracted in ‘bound to organic matter’ fraction would result from the oxidation of metallic forms by hydrogen peroxide and nitric acid used in the fraction, and, consequently, that the ‘bound to organic matter’ fraction should be investigated in detail to determine the removal method and treatment capacity when the Tessier’s sequential extraction method is used to examine heavy metal contaminants resulted from elemental metal like bullets.

• 한국환경과학회지
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• 제15권12호
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• pp.1171-1175
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• 2006

Deposited road particles (DRPs) were analysed for heavy metal concentrations at four different roads in a city, Korea. The samples were collected using a roadway surface vacuum cleaning vehicle which was commonly used in collecting roadway surface particles. Six particle size ranges were analyzed separately for twelve heavy metal elements (Cd, Cr, Pb, Ni, Al, As, Co, Cu, Fe, Mn, Zn and Hg). At all sampling sites, the high concentration of the heavy metals occurred in the <74um particle size range, which conventional roadway cleaning vehicles do not remove efficiently. The Pb concentration significantly increased with decreasing particle size of DRPs, and other toxic heavy metals (Cd, Cr and Ni) also showed similar results. The heavy metal concentrations in the smaller size fraction of DRPs is important because they are contaminants that are preferentially transported by road runoff during rainfall.

• 분석과학
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• 제16권2호
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• pp.174-178
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• 2003

Analytical chemists frequently use filter papers during the course of experiments without any hesitation. However, the results of analysis could be deteriorated by the various ions which are extracted from filter papers. In some filter paper made for qualitative use, about $300{\mu}g$ sodium and many other cations were detected. Although the quantities of contaminants was low in the filter paper made for quantitative use, significant amount of Fe, Si, Al, Cu and Zn was detected as well as alkali element. Many cations and anions were also detected in the filtrate obtained from the glass fiber filter.

• 한국물환경학회지
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• 제32권6호
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• pp.546-551
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• 2016

In this study, capping with recycled aggregate and natural zeolite in marine sediment was performed to investigate its inhibitory effect on pollutants released from sediment to seawater. An experiment was performed by capping with amendments for 60 days, and concentrations of organic matter (COD), nitrate, phosphate and metallic elements (Ni, Zn, Cu, Pb, Cd, As, and Cr) were measured. Two capping materials effectively suppressed pollutant release. Recycled aggregate showed better effectiveness for organic pollutant, nitrate and phosphate release. Meanwhile, natural zeolite was effective for metallic elements. As a result, recycled aggregate and natural zeolite can be considered as cost-effective/inexpensive capping material candidates. Also, the capping material can be selected according to the target pollutant.

• Bulletin of the Korean Chemical Society
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• 제35권1호
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• pp.69-75
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• 2014

Accurate analysis of fly ash particles is not trivial because of complex nature in physical and chemical properties. SPLITT fractionation (SF) was employed to fractionate the fly ash particles into subpopulations in large quantities. Then the SF-fractions were analyzed by the steric mode of sedimentation field-flow fractionation (Sd/StFFF) for size analysis. The SF-fractions were also analyzed by ICP-OES. The results showed that the fly ash is mainly composed of Fe, Ca, Mg and Mn. No particular trends were observed between the particle size and the concentrations of Fe, Ca, Mg, while Mn, Cu and Zn were in higher concentrations in smaller particles. Sample preparation procedures were established, where the fly ash particles were sieved to remove large contaminants, and then washed with acetone to remove organics on the surface of particles. The sample preparation and analysis methods developed in this study could be applied to other environmental particles.

• Advances in environmental research
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• 제2권2호
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• pp.99-118
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• 2013

Rainwater runoff has been identified as a significant source of contaminants having tremendous impact on the receiving aquatic environment. In the present study, trace element transport by the surface runoff in the predominantly urban catchment of Guwahati city, India was monitored with a view to determine the chemical denudation rates of the land surface. A number of trace metals, namely Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn were measured in the runoff after 70 major rain events within the city. Cadmium was found to be the least abundant metal and Iron was the most abundant metal in the runoff. The results are interpreted on the basis of temporal and spatial variations in their concentrations. These variations are quite large in some of the events and reflect changes in the local environmental setting, differences in water utilization, variations in runoff volume, gradient and quality.

• Bulletin of the Korean Chemical Society
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• 제20권9호
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• pp.1040-1044
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• 1999

A micro porous PTFE membrane desolvator (MMD) was built and evaluated for the on-line removal of organic solvents to facilitate the determination of trace metal contaminants in the solvents by ICP-AES. Three organic solvents, isopropyl alcohol (IPA), methanol, and dimethy sulfoxide (DMSO) were studied. The MMD reduced organic solvent concentration in the sample aerosol stream by 82% to 89%, as indicated by monitoring C(I) emission. Net signal intensity of Fe, Al, and Cu was increasing with higher organic solvent concentration, with the rate of increase being solvent dependent. The signal intensities for Mg and Pb followed the trend with the C(I) signal. Changing the sweep gas flow rate affected the optimum signal intensity. Wine samples were analyzed by the method of standard addition. The concentrations of B, Al, and Mg were determined with a relative precision of less than 2.3%.