• Title/Summary/Keyword: NiCd

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Distribution of trace metals in the deep ocean waters of the East Sea (동해심층수 개발해역의 미량금속 분포)

  • Kim, Kyung-Tae;Jang, Si-Hun;Kim, Eun-Soo;Cho, Sung-Rok;Park, Jun-Kun;Moon, Deok-Soo;Kim, Hyeon-Ju
    • Proceedings of KOSOMES biannual meeting
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    • 2006.11a
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    • pp.163-168
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    • 2006
  • In order to develop the deep ocean water, we performed to study the characteristics of vertical distribution of dissolved trace metals(Cd, Co, Cu, Ni, Pb, Zn) from Apr. to Oct., 2005 in the East Sea. Total six sampling sites were selected in Gangwon-Do and Gyeongsanbuk-Do. Accuracy of the analytical procedures was assessed by the SRM(CASS-4) for dissolved metals in seawater. The mean recoveries of CASS-4 ranged from 89.4% for Co to 99.8% for Cd. In this study, the dissolved metal concentrations varied with space, time and element. The metal concentrations showed wide range in the surface. Cd, Ni and Zn showed a nutrient-type profile with surface depletion and enrichment at depth. However, Co, Cu and Pb were irregular in the vertical distribution. All metal concentrations studied in this study are lower than the criteria of Korean drinking water.

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Studies on Heavy Metal Dissolution Characteristics from Sediments of Andong Dam (안동댐 퇴적물의 중금속 용출 특성 연구)

  • Seo, Jeong Min;Kim, Young Hun;Kim, Jeong Jin
    • Journal of the Mineralogical Society of Korea
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    • v.32 no.4
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    • pp.303-312
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    • 2019
  • In this study, X-ray diffraction, ICP analysis, and leaching experiments were performed to analyze the heavy metals and dissolution characteristics of Andong dam sediments. As a result of X-ray diffraction analysis, Andong dam sediment consists of quartz, plagioclase, chlorite and illite. ICP analysis of sediment showed very high concentrations of As and Cd. Leaching experiments were performed in aerobic and anaerobic condition in a disturbed state. The results of leaching experiment showed that more heavy metals were leached in aerobic than anaerobic conditions. Heavy metal that increased in concentration with time in aerobic conditions were Mn, Zn and Cd, and those in anaerobic conditions were Mn, Fe and As. The leaching ratio of heavy metal concentration in sediment was Mn > Cd > Zn > Ni > Cu > As > Pb ≒ Fe ≒ Cr and Mn > As > Cu > Ni > Zn > Pb ≒ Cd ≒ Fe ≒ Cr in aerobic and anaerobic conditions, respectively.

Heavy metals in the surface waters and sediments of Jinhae Bay, Korea (진해만 표층수와 표층 퇴적물 중의 중금속 분포)

  • Kim, Kyung-Tae;Kim, Eun-Soo;Cho, Sung-Rok;Kim, Jong-Kun;Park, Jun-Kun
    • Proceedings of KOSOMES biannual meeting
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    • 2007.05a
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    • pp.27-33
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    • 2007
  • Heavy metals in the surface seawaters and sediments were measured in Jinhae Bay. The high concentrations of heavy metals in the seawaters were found at the stations near the islands. In the sea waters, the mean concentrations of dissolved heavy metals except for Pb were not higher than previous data in this bay. Higher heavy metal contents in the surface sediments were observed at the stations adjacent to the Kojedo or Kadukdo of the Kadoksudo. The contents of Co, Ni, Zn, Cu, As and Cd in the surface sediments showed relatively high correlation coefficients with IL and COD. The order of enrichment factors(EFs) of heavy metals in the sediments was As>Cd>Pb>Zn>Co>Cu>Hg>Ni, and the EFs of As, Cd, Pb and Zn were higher than 1.

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Emission Characteristics of Blue Fluorescent OLED with Anode Materials (양극 물질에 따른 청색 형광 OLED의 발광 특성)

  • Kong, Do-Hoon;Lee, Yo-Seb;Ju, Sung-Hoo;Yang, Jae-Woong
    • Journal of the Korean institute of surface engineering
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    • v.48 no.3
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    • pp.121-125
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    • 2015
  • We studied the blue fluorescent OLED with Mg:Ag, Al, Ni as anode materials. Blue fluorescent OLEDs were fabricated using Anode / $MoO_3$ (3 nm) / 2-TNATA (60 nm) / NPB (30 nm) / SH-1 : BD-2 (5 vol.%, 30 nm) / Bphen (40 nm) / Liq (1 nm) / Al (150 nm). Current density of OLED with Mg:Ag was not measured due to too low work function, and that of OLED with Al showed $45.2mA/cm^2$ at 12 V. Luminance and Current efficiency of OLED with Al showed $385.1cd/m^2$ and 0.9 cd/A. Current density of OLED with Ni of 8, 10, 12 nm thickness showed 10, 12.9, $37.2mA/cm^2$, respectively. Luminance and Current efficiency of OLED with Ni of 8, 10, 12 nm thickness showed 670.9, 991.2, $1,320cd/m^2$ and 6.7, 7.7, 3.6 cd/A, respectively. Transmittance of Al was 52.2% at 476 nm wavelength and that of Ni of 8, 10, 12 nm thickness was 79, 77, 74 %, respectively. In spite of best current density, OLED with Al showed the lowest luminance and current efficiency because of low work function and poor transmittance. When thickness of Ni was increased to 12nm, current efficiency was sharply lower owing to bad transmittance and unbalance of holes and electrons. Finally, OLED with Ni of 10 nm thicknes showed the highest current efficiency.

Characteristics of Heavy Metal Pollution in Contaminated Roadside Sediments in Jeonju City, Korea (전주시 도로변 퇴적물의 중금속 오염 특성)

  • Cho, Ktu-Seong
    • Journal of the Korean earth science society
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    • v.24 no.8
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    • pp.711-720
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    • 2003
  • To study characteristics of the heavy metal pollution, sediment samples were collected at 67 sites on the roadside of Jeonju city during summer and winter, 2002. The total concentration of metals including Cd, Co, Cr, Cu, Ni, Pb, Zn, and Mn in the sediment samples were determined. The results indicate that the roadside sediments in Jeonju city have lower (1/2 to 1/7 times) concentrations of Zn, Cu, Pb and Cd than the metal concentrations previously reported for roadside soil, dust and sewage sludges in Seoul. However, the metal concentrations are higher than environmental quality criteria in soil suggested from several countries, and Zn, Cu, Pb and Cd contents are usually 2-7 times higher than the world average contents of the metals in natural soil. Although pollution index and concentrations of Cr, Ni, Pb and Zn in the roadside sediments at industrial area were usually higher than those of downtown and residential area, the metal having small vehicle- and steel-related industries had high concentrations of metals. The results of chemical partitioning analysis showed that Pb, Zn and Mn are mainly associated with carbonate/adsorbed and Fe-Mn oxide phases but that Cu is largely associated with the organic and sulfide fractions. It thus indicates that both large and small (vehicle- and steel-related) industries are main sources of heavy metal contamination. Due to high solubility of the carbonate phases by natural leaching episodes, the carbonate/adsorbed Cd, Co, Ni, Pb, Zn and Mn in the roadside sediments may serve as a potential source of contamination.

Characteristics and Assessment of Metal Pollution and their Potential Source in Stormwater Runoff from Shihwa Industrial Complex, Korea (시화산업단지 강우유출수 내 중금속 오염도 평가 및 오염원 추적 연구)

  • Lee, Jihyun;Jeong, Hyeryeong;Choi, Jin-Young;Ra, Kongtae
    • Korean Journal of Ecology and Environment
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    • v.53 no.1
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    • pp.91-101
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    • 2020
  • Stormwater runoff is known as a major non-point water pollution source that transports heavy metals, which have accumulated in road surface, to stream and coastal area. Dissolved and particulate metals in stormwater runoffs have been investigated to understand the outflow characteristics of heavy metals during rainfall events and to identify their pollution sources. The concentration of dissolved Co and Ni decreased after the outflow with high concentrations at the beginning of the rainfall, and other metals showed different characteristics depending on the rainfall and rate of discharge. Particulate metals showed a similar trend with the temporal variation of suspended solids concentration in stormwater runoffs. The results of geo-accumulation index (Igeo) indicated that the stormwater runoffs from industrial region were very highly polluted with Cu, Zn and Cd. As a result of comparing the metal concentrations of <125 ㎛ for road dust near the study area, Cu, Zn and Cd were originated from inside of metal manufacturing facilities rather than traffic activities at road surface and these metals accumulated on the surface area of facilities were transported to the water environments during stormwater event. The average discharged amounts of heavy metals for one rainfall event were Cr 128 g, Co 12.35 g, Ni 98.5 g, Cu 607.5 g, Zn 8,429.5 g, As 6.95 g, Cd 3.7 g, Pb 251.75 g, indicating that metal runoff loads in the stormwater runoffs are closely related to surrounding industry types.

Wet Deposition of Heavy metals in Suwon Area (수원지역 빗물의 중금속 함량 평가)

  • Jung, Goo-Bok;Lee, Jong-Sik;Kim, Won-Il;Kim, Jin-Ho;Yun, Sun-Gang
    • Korean Journal of Environmental Agriculture
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    • v.26 no.2
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    • pp.116-123
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    • 2007
  • This experiment was conducted to investigate the distribution and burden characteristics of heavy metals in the rainwater sampled at Suwon area, in the middle part of Korea, from April 2002 to October 2003. The relationship between concentration of heavy metal and other chemical properties in the rainwater was also evaluated. Chemical properties in the rainwater were various differences with raining periods and years. It appeared that a weighted average pH of rainwater was ranged from 4.7 to 5.5. Heavy metal concentrations in the rainwater were ranked as Zn>Pb>Cu>Ni>Cr>As>Cd. As compared with heavy metal concentrations of rainwater in 2002, Cd, Cu and As were higher than other element in 2003. There were positive correlation between major ionic components, such as Ca, Mg, and K, and heavy metal concentrations of rainwater, and As, CU, Cu, Zn and Ni were relatively higher relationship than Pb and Cr in respective to correlation coefficient. For heavy metal distribution of rainwater, the order of average enrichment factors was Cd>Pb>AS>Cu>Zn>Ni>Cr, and these were relatively higher than the natural component such as Fe, Mg and Ca. The monthly enrichment factors were relatively high in the spring (from April to May) at Suwon. The monthly amount of heavy metal precipitation was high in the rainy season from June to August because of great influence of rainfall.

Complex Formation of Transition and Post-Transition Metal Ions with 1,15-Diaza-3,4 : 12,13-dibenzo-5,8,11-trioxacyclooctadecane (전이 및 중금속이온과 1,15-diaza-3,4 : 12,13-dibenzo-5,8,11-trioxa-cyclooctadecane과의 착물형성)

  • Kim, Si-Joong;Lee, Myung-Jae;Koo, Chang-Hyung;Woo, Kyoun-Ja
    • Journal of the Korean Chemical Society
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    • v.35 no.6
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    • pp.645-652
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    • 1991
  • The stability constants$(K_f)$ of the complexes of some transition and post-transition metal ions (Co(Ⅱ), Ni(Ⅱ), Cu(Ⅱ), Zn(Ⅱ), Cd(Ⅱ), Pb(Ⅱ), Hg(Ⅱ)) with $N_2O_3$-donor macrocyclic ligand, 1,15-diaza-3,4 : 12,13-dibenzo-5,8,11-trioxacyclooctadecane ($NtnOdienH_4$), have been determined by potentiometry in aqueous solution at $25^{\circ}C$. Log $K_f$ values of the complexes were : Co(Ⅱ): 3.83, Ni(Ⅱ) : 4.56, Cu(Ⅱ) : 7.74, Zn(Ⅱ) : 4.98, Cd(Ⅱ) : 3.91, Pb(Ⅱ) : 6.65, and Hg(Ⅱ) : 14.87. The order of stabilities of transition metal complexes was the same as the natural order of stability proposed by Williams-Irving. In post-transition metal complexes, the order of stabilities was Cd(Ⅱ) < Pb(Ⅱ) < Hg(Ⅱ), and the covalent character in metal ion-donor atoms bonds appeared a dominant factor in the stability. In methanol solution, each metal ion forms 1 : 1 complex, while Ni(Ⅱ) ion forms both 1 : 1 and 1 : 2 complexes. It was confirmed by $^1H-$ and $^{13}C-$NMR spectral study that the nitrogen atoms in the ligand were major contributors for the complexation of post-transition metal ions with the ligand. It was shown, by elementry analysis, electrical conductivity and magnetic susceptibility measurements, and spectral analysis, that solid Cu(Ⅱ)-and Zn(Ⅱ)-complexes have a distorted octahedral and a tetrahedral structure, respectively.

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퇴적물의 산성화에 따른 우수관 퇴적물의 중금속 용출특성과 존재형태 연구

  • 이평구;유연희
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2001.09a
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    • pp.249-253
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    • 2001
  • 퇴적물에 오염된 중금속의 지화학적 특성을 규명하고자, 연속추출방법을 이용하여 구성광물 과의 지구화학적 수반관계와 산성화에 따른 중금속 용출특성을 연구하였다. 용출실험과 연속추출 실험을 종합한 연구결과, 서울시 도로변의 하수퇴적물이 산성비와 같은 요인에 의해 pH 5.0정도의 약산성환경과 접촉하였을 때 중금속의 상대적인 용출특성은 Zn>>Cd$\geq$Co>Ni>Cu$\geq$Pb>Cr이며, 원소별 용출량은 Zn 40-90%, Cd 10-30%, Co 15-25%, Ni 5-25%, Cu 0-20%, Pb 0% 및 Cr 0% 이었다. 하수퇴적물에 오염된 Zn, Cd, Cu 및 Ni의 용출은 매우 우려할 만한 수준이며, 수계의 물리화학적 변화(pH 등)에 따라 이들 원소의 일부분이 용해되어 지표수 및 강물을 오염시킬 것으로 예상된다.

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동전기 현상을 이용한 광미의 중금속류(As,Pb,Cd,Zn,Cu,Ni) 제거효율 연구

  • On Ji-Won;Choi Chang-Sik;Kim Ho
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2006.04a
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    • pp.224-225
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    • 2006
  • 점토성 오염토양을 원위치 정화하는데 효과적인 것으로 알려진 Electrokinetic정화기술을 이용하여 폐광산의 광미를 대상으로 실험을 수행하였다. 실험은 초기 인가 전류 0.01A, 170V의 정전압모드로 약 950시간동안 운전하였으며, 투입된 총전력량은 5671.455 WH으로시간당 5.97W의 전력이 투입되는 것이다. 중금속류(As,Pb,Cd,Zn,Cu,Ni)에 대하여 $50{\sim}90%$의 제거효율을 보였으며 중금속 농도는 점차 감소하고 중금속별로 $Zn{\cong}Cd>Ni>Cu{\cong}Pb{\cong}As$ 의 경향을 보였다.

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