• Title/Summary/Keyword: lead metal

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Characteristics of Lead Removal by Methanotrophic Biomass (메탄자화균에 의한 납의 제거 특성)

  • 이무열;양지원
    • KSBB Journal
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    • v.15 no.5
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    • pp.444-451
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    • 2000
  • Nonliving methanotrophic biomass was used as biosorbent to remove lead which is one of representative pollutants in metal-bearing wastewater. Solution pH, maximum uptake, biosorbent dose and ionic strength were considered as major factors for adsorption experiments. The optimum pH range for lead removal was increased 3.8∼11.0 for methanotrophic biomass compared to biosorbent-free control, pH of 8.4∼11.2. Removal efficiency of lead by methanotrophic biomass was pH dependent, but less sensitive than that of control. In isotherm experiments with 0.2g biosorbent/L at initial solution pH 5.0, methanotrophic biomass took up lead from aqueous solutions to the extent of 1085 mg/g biomass. Removal amount of lead increased with an increase of biomass dose. According to biomass dose for initial 1000 mg Pb/L at initial pH 5.0, the optimum amount of biomass for maximum lead removal per unit methanotrophic biomass was 0.2 g biomass/L. As a result of scanning electron microscope (SEM) micrographs equipped with energy dispersive spectroscopy (EDS), lead removal by methanotrophic biomass seemed to be through adsorptions on the surface of methanotrophic biomass and exopolymers around the biomass. EDS spectra confirmed that lead adsorption appeared on the biomass and exopolymers that may be effective to lead removal comparing before and after contact with lead. Removal efficiency of lead was slightly affected by ionic strength up to 2.0 M of NaCl and NaNO$_3$respectively.

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Characterization of lead isotope emission profiles in non-ferrous smelters in South Korea (국내 비철금속 제련시설에서의 납 동위원소 배출특성 연구)

  • Park, Jin-Ju;Kim, Ki-Jun;Park, Jin-Soo;Yoo, Suk-Min;Park, Kwang-Soo;Seok, Kwang-Seol;Shin, Hyung-Sun;Song, Guem-Joo;Kim, Young-Hee
    • Analytical Science and Technology
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    • v.26 no.5
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    • pp.333-339
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    • 2013
  • This study was conducted to build up the inventories of Pb isotopic compositions of major Pb pollution sources in South Korea. Since non-ferrous metal smelters are one of major anthropogenic sources, two smelters for zinc, each one of smelter for lead and copper were selected for the study. The Pb concentrations and isotopic compositions of metal ores, wastewater, sludge, metal rod and produced sulfuric acid were analysed to understand the Pb isotopic patterns in environment. The isotopic ratio, $^{206}Pb/^{207}Pb$, of zinc ores from zinc smelter were in the range of 1.179~1.198 and the ratio of waste, flue gas and products samples were 1.105~1.147. This results implied that the isotopic patterns of output samples showed mixing patterns between two distinct metal ore soerces. In 2011, major importing countries of zinc ore were Australia, Peru and Mexico. Thus Pb isotopic patterns from zinc smelter is originated from the mixing patterns between less radiogenic Australian ores and more radiogenic South America's ores. Lead smelters also showed the same mixing patterns with those of zinc smelters. However copper smelter showed same Pb isotopic patterns with more radiogenic South America's ores.

Adsorption Characteristics Evaluation of Natural Zeolite for Heavy-metal Contaminated Material Remediation (중금속 오염물질 정화를 위한 천연제올라이트의 흡착특성)

  • Shin, Eun-Chul;Park, Jeong-Jun;Jeong, Cheol-Gyu;Kim, Sung-Hwan
    • Journal of the Korean Geosynthetics Society
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    • v.13 no.2
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    • pp.59-67
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    • 2014
  • The amount of the contaminants that can be adsorbed on the drain was evaluated for the effective remediation of the contaminated soil, and the contaminants adsorptivity of the drain was evaluated by comparing the isothermal adsorption model after carrying out the contaminants adsorption test of the reactants coated on the surface of the drain. The reactant used in the experiment is a natural zeolite, and the contaminants are copper, lead and cadmium. The results that Freundlich and Langmuir adsorption isotherm model are compared to the adsorption amount according to the change of the initial concentration by the contaminants. As a result of the component analysis, because Si, Al and O are contained approximately 28%, 11% and 48%, respectively, it is identified that the material coated on the surface of the drain is the component of the zeolite which is the reactant for the adsorption of the heavy-metal (Cu, Pb, Cd) contaminants. The heavy-metal adsorption kinetic of the zeolite which is the reactant was decreased in order of lead, copper and cadmium. The important factor of the performance evaluation of the adsorbent is the reaction rate, and if zeolite is used as the reactant in the relationship between the maximum amount of adsorption and reaction rate, it can be utilized as the design factor that determine the removal order of the complex heavy-metal. In other words, because the maximum adsorption quantity of lead is smaller compared to copper but the reaction rate is relatively fast, it can be primarily removed, and copper can be removed after removing the lead. It was analyzed that Cadmium can be finally removed after that other heavy-metal is removed.

Studies on the Heavy Metals Elimination and Antioxidation of the Onion Ethnolic Extract (양파 알코올 추출물의 항산화 효과 및 중금속 제거 가능성 연구)

  • Lee, Mi-Kyung;Chung, Young-Hee;Nam, Hyun-Keun
    • Journal of the Korean Applied Science and Technology
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    • v.16 no.2
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    • pp.143-146
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    • 1999
  • In order to study for Onion ethanolic extract on the Heavy Metal Elimination and antioxidation, the peroxide values of oil and eliminated metal were analyzed. The results are follows: It was very effective as a retardant for autoxidation processing of the soybean and olive oil by the Onion ethanolic extract. Quercetin in the Onion ethanolic extract was affected as a ligand for chelating with some metals. Through out this study, Quercetin in the Onion ethanolic extract was affected as eliminator of the Mercury, Lead, and Cadmium.Abstracts In order to study for Onion ethanolic extract on the Heavy Metal Elimination and antioxidation, the peroxide values of oil and eliminated metal were analyzed. The results are follows: It was very effective as a retardant for autoxidation processing of the soybean and olive oil by the Onion ethanolic extract. Quercetin in the Onion ethanolic extract was affected as a ligand for chelating with some metals. Through out this study, quercetin in the Onion ethanolic extract was affected as eliminator of the mercury, lead, and cadmium.

Heavy Metal Characteristics of Fish in Watersheds of the Upper Region of the Nakdong River (낙동강 상류 유역별 서식 어류의 중금속 특성)

  • Kwon, Hee Won;Kim, Young Hun;Kim, Jeong Jin
    • Journal of Environmental Science International
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    • v.31 no.2
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    • pp.103-116
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    • 2022
  • Heavy metal contaminations were investigated in fishes inhabiting the basins of Andong, Imha and Yeongju dam basins along the upper stream of the Nakdong river. The characteristics of heavy metals contamination in fish were investigated based on sampling sites located in the Andong dam basin. The muscle tissue was analyzed for 267 objects of 26 species from the Andong dam, 50 objects of 17 species from Imha dam, 38 objects of 9 species fromYoungju dam basin.The type and amount of heavy metals concentrated in the body of the fishes was found to be species-dependent. The heavy metal species which contamination increase through the Seokpo smelter are chromium, zinc, cadmium, and lead, and these are very likely the influence of the smelter. The concentration of eight heavy metals in fish from the Andong dam basin was higher than that in fish from the Imha and Youngju dam basins; the values for zinc, arsenic, and cadmium were significantly higher. However, mercury and lead exhibited high values in the Imha and Yeongju dam basins, respectively.

Characteristics of Heavy Metal Distribution in Bottom Sdeiments of Tributaries of the Han River (한강유역 주요지천의 저질내 중금속 분포)

  • 허준무;박종안
    • Journal of environmental and Sanitary engineering
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    • v.14 no.3
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    • pp.71-79
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    • 1999
  • The Hg, Cd, Cu, Mn, and Zn in bottom sediments of han river and their tributaries were analyzed to evaluate the seasonal variations of heavy metals. Leaching tests were also performed for estimation of availability of heavy metal retention in sediments. Sediments of Anyang stream showed the highest concentration of heavy metal in the sediment samples. Heavy metal concentration was heavily depended upon the heavy metal source of tributaries of han river and particle distribution. Clay and silt had higher concentration of heavy metals than very fine san and fine sand due to difference of retention capability of heavy metal. The highest concentration of heavy metal was observed in bottom sediments irrespective of sites investigated. Heavy metals and ignition loss showed positive relations, and higher relationships with p-value <0.01 were observed between copper and lead. copper and zinc, and depended on the pH condition of leaching test, and leachated fraction increased with decrease of the pH.

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Effect of Metal Ions on Speroxide Dismutase of the Liver in Senescence-Accelerated Mouse(SAM) (노화촉진생쥐(SAM)의 간에서 금속이온이 SOD의 활성에 미치는 영향)

  • 양미경;박문숙
    • Journal of environmental and Sanitary engineering
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    • v.15 no.2
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    • pp.1-9
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    • 2000
  • This research employed a senescence-accelerated mouse(SAM) to explore the possibility that differences exits among the major antioxidants, superoxid dismutase(SOD), in terms of ability to protect such animal treated with Cu, Fe and Mn. To assess the antioxidants function of metal ions on SAM-R/1 and SAM-P/8 were administered with Cu, Fe and Mn orally. The effect of metal ions on SAM towards reversing oxygen sensitivity was determined as a bioassays of SOD in the mouse liver. The data show that the SOD activity was induced by each metal ions in both SAM-R/1 and SAM-P/8. It suggested that induced SOD by each metal ions may protect against oxidative mediated stress. Finally, overall data lead to the possibility of metal ions as an antioxidants or each metal ions act producer of oxygen radicals in the liver of SAM-R/1 and SAM-P/8.

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Effect of Dietary Cysteine Level on Cadmium on Cadmium and Lead Toxicity in Rats (식이내 Cysteine 수준이 흰쥐의 카드뮴과 납중독에 미치는 영향)

  • 류정미
    • Journal of Nutrition and Health
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    • v.29 no.6
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    • pp.597-607
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    • 1996
  • This study has been investigated the potenial of increased dietary cysteine to alter the effects of cadmium and lead on tissure and bone metal concentrations, excretion and tissue metallothionein(MT) concentrations. Fifty-four male rats of Sprgue-Dawley strain weighing 149$\pm$17g were divided into 9 groups according to body weight. Nine experimental diets with different cadmium (0ppm, 400ppm), lead(0ppm, 710ppm) and cysteine (0.06%, 0.45%, 0.90%) levels were given to rats for 30 days ; Food intake, weight gain, F.E.R, and weights of liver, kidney and femur were decreased in cadmium supplied groups than in cadmium free groups. Urinary and fecal cadmium excretions were increased and MT synthesis we induced in liver, kidney and small intestine in cadmium supplied groups. In lead supplied groups, weight gain and F.E.R were decreased. With cysteine supplementation in cadmium supplied groups, weight gain and F.E.R, and weights of liver, kidney and femur were increased. Cadmium excretion in feces and MT concentrations in liver and kidney were also increased with cysteine supplementation. In lead supplied groups, there was no significant increase in food intake, weight gain and F.E.R with cysteine supplementation. Lead excretion in feces was increased in cysteine supplemented groups. In conclusion, effect of cadmium administration was more toxic than lead adminstration. Cysteine alleviated cadmium and lead toxicity by increasing metallothionein concentration and fecal excretions of heavy metals. Especially, effect of cysteine supplementation was more effective in cadmium groups than in lead groups. Effect of cysteine supplementation was not different with level of cysteine supplementation in both cadmium and lead groups.

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Normalized Contact Force to Minimize "Electrode-Lead" Resistance in a Nanodevice

  • Lee, Seung-Hoon;Bae, Jun;Lee, Seung Woo;Jang, Jae-Won
    • Bulletin of the Korean Chemical Society
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    • v.35 no.8
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    • pp.2415-2418
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    • 2014
  • In this report, the contact resistance between "electrode" and "lead" is investigated for reasonable measurements of samples' resistance in a polypyrrole (PPy) nanowire device. The sample's resistance, including "electrode-lead" contact resistance, shows a decrease as force applied to the interface increases. Moreover, the sample's resistance becomes reasonably similar to, or lower than, values calculated by resistivity of PPy reported in previous studies. The decrease of electrode-lead contact resistance by increasing the applying force was analyzed by using Holm theory: the general equation of relation between contact resistance ($R_H$) of two-metal thin films and contact force ($R_H{\propto}1/\sqrt{F}$). The present investigation can guide a reliable way to minimize electrode-lead contact resistance for reasonable characterization of nanomaterials in a microelectrode device; 80% of the maximum applying force to the junction without deformation of the apparatus shows reasonable values without experimental error.

Comparison of Lead and Cadmium Levels in Tissues of Feral Pigeons(Columba livia) from Rural, Central Urban, and Industrial Complex Areas (섬, 도심, 공단지역에서 서식하는 비둘기의 체내 납, 카드뮴 농도 비교)

  • 남동하;이두표;구태회
    • The Korean Journal of Ecology
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    • v.25 no.5
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    • pp.329-334
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    • 2002
  • In order to compare the lead and cadmium levels, studies of heavy metal accumulation of feral pigeons from rural (Deokjeok island), central urban (Seoul city), and industrial complexes (Ansan, Busan, Ulsan, and Yochon) were conducted. The outstanding result of this study is that feral pigeons in urban and industrial complex areas contain high Pb and Cd concentrations in kidney, bone, liver, and lung tissues compared to those of rural areas. Such a trend was prominent in the target organs, bone and kidney, about 10 times greater than in rural areas. On the other hand, the lead levels of the Yochon Industrial Complex were noticeably lower than those of other industrial complex areas. Not only feral pigeons habit of street and ground feeding, but also atmospheric metal concentration offers an explanation for the heavy metal concentration differences in the study areas.