• Title/Summary/Keyword: Metal contamination

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광미를 이용한 납 오염토양의 향상된 Electrokinetic 정화

  • 조용실;김정환;한상재;김수삼
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2002.04a
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    • pp.279-282
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    • 2002
  • In this study, mine tailing buffer zone in cathode was used to overcome precipitation of heavy metals that reducing remediation efficiency during electrokinetic remediation. Test results showed that heavy metal transportation affected by initial soil pH which was verified through traditional test and enhanced test with two type of soils. With mine tailing enhanced method 39% of extraction rate was achieved in surface soil and significant transportation trend was observed in deep soil.

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Metal contamination of fluorides used for municipal water fluoridation and mouth rinse (수돗물 불소화 및 불소양치사업에 사용되는 불소화합물의 금속 오염도)

  • 이은희;송현주;안혜원
    • Proceedings of the Korea Society of Environmental Toocicology Conference
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    • 2001.05a
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    • pp.135-135
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    • 2001
  • 수돗물 불소화사업이란 치아우식증 (충치)을 예방할 목적으로 0.8ppm의 불소를 수돗물에 첨가하는 공중보건사업이며, 수돗물 불소화사업이 시행되지 않고 있는 서울시내 초등학교에서는 1995년부터 불화나트륨용액 (0.2%용액으로 매주 1회 또는 0.05%용액으로 매일 1회)으로 불소양치를 실시하고 있으며, 서울시 일부 보육시설에서는 만4세-6세의 취학전 아동을 대상으로 불소용액양치사업 (0.25% 용액)을 1997년부터 실시하고 있다. (중략)

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Novel Method for the Measurement of Secondary Stickies in Process Water of Newspaper Recycling Mill (신문지 재활용 공정의 이차 점착성 이물질 정량을 위한 새로운 방법)

  • 박진성;류정용;김용환;송봉근
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2002.05a
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    • pp.34-45
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    • 2002
  • The new measuring method of micro-stickies considering both the effects of charge neutralization and evaporation of process water was developed by KRICT PPRC. By the new KRICT method, the contamination of metal dryer surface and other machine clothes could be estimated quickly and simultaneously. According to this study, it could be confirmed that the novel method is a useful one for the evaluation of several treatments regarding the reduction of stickies troubles.

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Supercapacitors using Pure Single-walled Carbon Nanotubes

  • Tanaike, Osamu;Futaba, Don N.;Hata, Kenji;Hatori, Hiroaki
    • Carbon letters
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    • v.10 no.2
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    • pp.90-93
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    • 2009
  • The excellent and characteristic capacitor performance of pure single-walled carbon nanotubes (SWNTs), which differ from conventional activated carbon electrodes, is reported. SWNTs with little bundling showed higher specific capacitance than activated carbons. High operating voltage can be expected for pure SWNTs without metal contamination and graphene edge structure.

Heavy Metal Contents of Soil and Pear Tree near a Major Road (도로변 배나무 과수원 토양과 수체의 중금속 함량)

  • Jeon, Byung-Doo;Choi, Jong-Seung
    • The Journal of Natural Sciences
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    • v.19 no.1
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    • pp.65-75
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    • 2008
  • This research was conducted to determine heavy metal contents of soil and tree in pear orchard located near national road with heavy traffics. Topsoil (0-15 cm depth) and subsoil (15-30 cm) samples in pear orchard located within 40 m from national road had higher Pb, Cu, and Zn contents than background orchard (BG) and these heavy metal contents decreased with distance from road. Topsoil samples taken at 10 m from national road had 4 times higher level in Pb, 3 times in Cu, and 2.5 times in Zn compare to BG. The Cd contents of topsoil in orchard were higher than those of BG but were not in subsoil. Highest heavy metal contents of pear leaves in roadside orchard were 20.08 in Pb, 7.02 in Cu, 30.83 in Zn, and $1.68\;mm.kg^{-1}$ in Cd and these heavy metal contents in roadside orchard were higher than BG. Cd contents of fruit and Pb contents of fruit stalk in roadside orchard were higher than BG and these heavy metal contents decreased with distance up to 40 m from the road.

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Distribution of Cd and Pb Accumulated in Medicinal Plant Roots and Their Cultivation Soils

  • Seo, Byoung-Hwan;Kim, Hyuck Soo;Bae, Jun-Sik;Kim, Won-Il;Hong, Chang-Ho;Kim, Kwon-Rae
    • Korean Journal of Soil Science and Fertilizer
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    • v.48 no.4
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    • pp.278-284
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    • 2015
  • In general, plant roots accumulate more heavy metals than the above ground organs such as leaf, stem, and fruit. This implies that root medicinal plants would be an issue with excessive heavy metal accumulation. Therefore, the current study was carried out to investigate the distribution of heavy metal (focused on Cd and Pb) concentrations in soils and medicinal plant roots grown in different region of Korea. Total 293 samples for each soil and plant were collected along the national wide. Soil pH, total and phytoavailable metal concentrations (1 M $NH_4NO_3$ extracted) in soils were determined and heavy metal concentrations in root of the medicinal plants were analyzed. Heavy metal concentrations of the soil samples studied were not exceeded standard limits legislated in 'Soil Environmental Conservation Act', except 2 samples for Cu. However, substantial amount of Cd was accumulated in medicinal plant roots with 29% samples exceeding the standard limit legislated in 'Pharmaceutical Affairs Act' while all plant samples were lower than the standard limit value for Pb. Also the current study demonstrated that cadmium concentrations in the roots were governed by the phytoavailable Cd in soils, which decreased as soil pH increased. From this result, application of heavy metal immobilization technique using a pH change-induced immobilizing agents can be suggested for safer root medicinal plant production.

Analysis of Copper, Zinc in Serum Using ICP-MS & AAS (ICP-MS와 AAS를 이용한 체내 혈청 Cu, Zn 분석에 관한 연구)

  • Lee, Yea-Jin;Kim, Dong-Yub;Lee, Go-Eun;Jo, Young-Suk
    • Korean Journal of Clinical Laboratory Science
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    • v.41 no.1
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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.

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Time Dependant Ozone Generation due to Oxidation of the Surface of Corona Discharge Wires (코로나방전선 표면 산화에 따른 오존발생량의 경시특성)

  • Jung, Sung-Jin;Park, Seung-Lok;Moon, Jae-Duk
    • Proceedings of the KIEE Conference
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    • 2000.07e
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    • pp.22-25
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    • 2000
  • Time dependent ozone generation characteristics of some oxide layers grown by ozone on the surface of corona discharge wires have been investigated experimentally in air ambience. Four wires of stainless steel, iron, silver and copper were used for the corona discharge wire of an ozone generator. And the effect of the metal oxide layers on ozone generation was studied and the contamination morphology of each layers was characterized. With the SEM images and the EDS spectra, it was found that all the surface of the corona wire were oxidized by the generated ozone and contaminated by airborne particles through the gradient force. As a result, the morphology and the electrical property of metal oxide layer grown on corona wire surface influenced on ozone generation characteristics i.e. discharge mechanisms.

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A Study on Water Quality of Springs in the Suburbs of Chunchon City According to Seasons (춘천근교 약수의 계절별 수질에 관한 보건학적 조사연구)

  • 한돈희;박영의;박찬정;전병구;박갑만
    • Journal of Environmental Health Sciences
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    • v.13 no.1
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    • pp.7-16
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    • 1987
  • A study was carried out to determine the adequacy of springs as drinking water in summer and in winter separately. In this study, environmental sanitation, physio-chemical examination, bacteriologic contamination and the content of heavy metal were included. For this study, samples were collected from 8 springs which were located in the suburbs of Chunchon city. The following results were obtained. 1. There was the covering system in 1 out of 8 springs. 6 out of 8 springs showed contaminating source within lorn. 2. In physio-chemical test, six out of 8 springs were found to be unsafe for the legitimate standard of safty water. 3. Bateriologic examination clone during summer showed the evidence of coilform group at 7 out of 8 springs and during winter showed positivity at 3 out of 8 springs. 4. In the study for heavy metal content, all places showed high iron level beyond the standard level of salty water, and 4 places showed high contents of fluorine, mangan and lead.

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