• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 추계학술발표회
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• pp.291-295
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• 2002

We measured the concentrations of heavy metals and VOCs in groundwaters (N=38) in Seoul. The comparison of our data with U.S. Environmental Protection Agency's Maximum Contaminant Levels for Drinking Water and with the Korean Drinking Water Standards shows that most of the metals except for Fe and Mn do not exceed the levels. However, the concentrations of most heavy metals (esp., Zn, Cu, Cr, Ni) tend to increase in residential and industrialized areas. The examination of the metal speciation using Anodic Stripping Voltammetry (ASV) and TOC analyzer Indicates that large amounts of Zn occur as labile metal fraction, whereas Cu occurs as non- labile forms at many sites, possibly due to its tendency to be adsorbed onto inorganic colloidal particles to form electroinactive species in groundwater. The most frequently existed VOCs in Seoul groundwaters are trichloroethylene and tetrachloroethylene, especially in agricultural, industrial, and high traffic areas.

• Membrane and Water Treatment
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• 제7권6호
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• pp.555-571
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• 2016

Heavy metal contamination has attracted considerable attention during recent decades due to the potential risk brought about for human beings and the environment. Several adsorbent materials are utilized for the purification of contaminated water resources among which chitosan is considered as an appropriate alternative. Copper is a heavy metal contaminants found in several industrial wastewaters and its adsorption on porous and macroporous chitosan membranes is investigated in this study. Membranes are prepared by phase inversion and particulate leaching method and their morphology is characterized using SEM analysis. Batch adsorption experiments are performed and it is found that copper adsorption on macroporous chitosan membrane is higher than porous membrane. The iso-steric heat of adsorption was determined by analyzing the variations of temperature to investigate its effect on adsorption characteristics of macroporous chitosan membranes. Furthermore, desorption experiments were studied using NaCl and EDTA as eluants. The mechanism of copper adsorption was also investigated using XPS spectroscopy which confirms simultaneous occurrence of chelation and electrostatic adsorption mechanisms.

• 한국식품영양과학회지
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• 제28권1호
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• pp.22-27
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• 1999

This study was performed to investigated the contamination levels of harmful heavy metals were sampled from Aug. 1 to Aug. 31, 1997, at 9 areas in Cheonbuk area. The heavy metal contents were determinated by ICPS(Inductively Coupled Plasma Spectrometer) method. The levels of total lead, cadmium, aluminum, iron and copper were determined and the results were summarized as follows: The minimum and maximum values(ppm) of 9 areas of Carassius auratus were Pb: 2.03~6.19, Cd: 0.06~ 0.76, Al: 8.84~23.5, Zn: 10.68~48.71, Cu: 0.60~1.51ppm. Among the five heavy metals contents, the highest was zinc and the lowest was cadmium. The results showed that the contents of Pb, Cd, Al, Zn and Cu in Carassius auratus were lower than the FAO/WHO maximum allowance.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.611-612
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• 2006

In a manufacturing technique of the sintered filter, pressureless sintering method has good permeability, it is not need the binder and lubricant used on compacting process, so it has little contamination and it is easy to control the pore size and shape but the mechanical strength is low relatively and it is difficult that parts of complicate form are manufactured. In the case of manufacturing the filter by press and sintering method, in order to be satisfactory characteristic of un-pressed filter, in this study sintered metal filter fabricated by using 30-40mesh stainless steel 316L powder and additive agents. Porosity and structure of pores, permeability and mechanical strength of the sintered filter were investigated with the variation sintering conditions. Porosity was nearly constant about $60{\sim}70%$, density, permeability and mechanical strength were changed markedly with quantity of additive materials and sintering conditions.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.422-423
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• 2006

Ultrasonic-milling of metal oxide nanopowders for the preparation of tungsten heavy alloys was investigated. Milling time was selected as a process variable. XRD results of metal oxide nanopowders ultrasonic-milled for 50 and 100h showed that mean crystallite size reduced with increasing milling time and there was no evidence of contamination or change of composition by impurities. It was found that nanocomposite powders reduced at $800^{\circ}C$ in $H_2$ atmosphere had a composition of 93.1W-4.9Ni-2.0Fe by EDX analysis. Hardness of sintered samples of 50 and 100h was 390 and 463 Hv, respectively, which corresponds to the hardness of commercial products.

• Mycobiology
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• 제44권4호
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• pp.277-282
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• 2016

In this study, we collected rhizosphere soils and root samples from a post-mining area and a natural forest area in Jecheon, Korea. We extracted spores of arbuscular mycorrhizal fungi (AMF) from rhizospheres, and then examined the sequences of 18S rDNA genes of the AMF from the collected roots of plants. We compared the AMF communities in the post-mining area and the natural forest area by sequence analysis of the AMF spores from soils and of the AMF clones from roots. Consequently, we confirmed that the structure of AMF communities varied between the post-mining area and the natural forest area and showed significant relationship with heavy metal contents in soils. These results suggest that heavy metal contamination by mining activity significantly affects the AMF community structure.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.295.1-295.1
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• 2002

Metallothioneins (MTs) are a go up of heavy metal-binding proteins characterized by cystein-rich low molecular weight(6000 - 10.000 Da). They plays a major role in the detoxification of heavy metals and also in scavenging of superoxide radicals. They are known to be induced by heavy metals in various organs of different species and represent a potential biomarker of aquatic heavy metal contamination. (omitted)

• 한국환경과학회지
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• 제16권5호
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• pp.657-664
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• 2007

The content and distribution of some heavy metals (Fe, Mn, Cr, Co, Cu, Ni, Zn and Pb) were investigated in the <$63{\mu}m$ bed sediments of the Mangyeong river to recognize the extent of contamination. Results showed that a wide range of concentrations was apparent for every metal. These variations were particularly significant at the confluence of tributaries. High levels of metals occur mainly in the confluence of tributaries. Geoaccumulation indexes have been calculated to assess whether the concentration observed represent background or contaminated levels. It is proved that the Mangyeong River is moderately to strongly polluted for Mn, Cr, Cu, Zn and Pb. The spatial extent of pollution was examined, and it was found that the most polluted area is located in the confluence of Iksan and Jeonju tributaries.

• 펄프종이기술
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• 제41권2호
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• pp.55-63
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• 2009

This study was performed to evaluate the heavy metal contents in various packaging board. Domestic and foreign OCC (old corrugated containers) and old duplex boards were used as raw materials. Tests were made for the printed and unprinted parts of the sample. Heavy metal contents of old food packaging boards made from virgin pulp fibers were also evaluated. The contents of heavy metals including lead (Pb), cadmium (Cd), barium (Ba), arsenic (As), antimony (Sb), selenium (Se), and mercury (Hg) were determined using ICP-AES (Inductively Coupled Plasma - Atomic Emission Spectrometer), and CV-AAS (Cold vapor-atomic absorption spectrometer) after digesting the samples in a microwave oven. The contents of heavy metals contained in domestic packaging board were higher than those in overseas samples, and OCC showed higher contents of heavy metals than old duplex boards. Printed parts gave greater heavy metal contents than unprinted parts. Results indicate that recycling of paper and paperboard products increases the heavy metal contamination of the paper packaging products and this derives mostly from the heavy metals contained in printing inks. Recycling processes that decrease heavy metals in recycled fibers and new printing inks that contains less heavy metals should be developed to solve the problem associated with the heavy metals in packaging paper products.

• 생태와환경
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• 제43권3호
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• pp.377-384
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• 2010

안동호와 임하호에 서식하고 있고 누치(H. labeo)의 부위(아가미, 신장, 뼈, 비늘, 근육)에 따른 각 조직 내 중금속(Al, As, Cr, Cd, Hg, Pb, Cu, Fe, Mn, Zn) 함량을 측정하여 양호의 서식환경에 따른 누치의 부위별 중금속 축적량을 알아보고자 하였다. 안동호와 임하호에 서식하는 누치의 중금속 함량은 안동호에서 높았으며, As, Cd과 Hg은 함량의 차이가 컸다. Al, As와 Fe의 함량은 모두 아가미 조직에서 가장 높았고 근육 조직에서 가장 낮았으며, Zn 함량은 조사된 모든 부위에서 거의 동일한 수준을 보였다. 또한 Al, Cr, Cu와 Mn 함량은 임하호에 서식하는 누치에서 보다는 안동호에 서식하는 누치의 아가미와 신장 조직에서 높게 나타났다. 본 연구의 결과 안동호에 서식하는 누치가 임하호에 서식하는 누치보다 중금속 함량이 높았으며, 이는 안동호의 수질과 저니에서 중금속 함량이 높은 것으로 보아 수환경의 수질과 저니에 포함된 유기물을 어류가 먹이로 섭취함으로써 어류에서도 높은 함량을 보인 것으로 생각된다.