• Title/Summary/Keyword: Nd-Cu-Zn

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Heavy Metal Distributions of Soils in the Vicinity of Shi-Hwa Industrial Complex Region (시화공업단지 주변지역 토양의 중금속 분포)

  • 송영배;이상모
    • Journal of Soil and Groundwater Environment
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    • v.8 no.2
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    • pp.87-91
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    • 2003
  • This study was carried out to investigate the heavy metal distributions of soils in the vicinity of Shi-Hwa industrial complex region, where the air pollutants from industrial area could affect the soil environment of near residential and green areas. The ranges of contents of As, Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn in soils were 0.58~3.81, ND~0.91, 0.15~6.33, ND~l.86, 0.14~110.27, ND~l.17, 0.04~10.59, 1.16~86.48 and 1.83~212.65 mg/kg, respectively. For all industrial, residential and green areas, the heavy metal contents were much lower than the standard of Korean Soil Environmental Preservation Act or the critical concentration which phytotoxicity is considered to be possible. Mean values of contents of As were similar in industrial, residential and green areas. However, the mean values of contents of Cd and Cr in industrial area were higher 10 and 5 times than those in residential and green area, respectively. And also the mean values of contents of Co, Cu, Hg, Ni, Pb and Zn in industrial area were higher 2~3 times than those in residential and green area.

EFFECT OF BINARY ADDITIVES ON THE MAGNETIC PROPERTIES OF MECHANICALLY GROUND Fe-Nd-B MAGNETS

  • Jang, T.S.;Park, J.D.;Jeung, W.Y.
    • Journal of the Korean Magnetics Society
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    • v.5 no.5
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    • pp.421-426
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    • 1995
  • The magnetic properties of the hot-pressed magnets made from the Fe-Nd-B alloys, mechanically ground and subsequently blended with binary additives such as Al-Cu and Ag-Zn before hot pressing, were investigated. The coercivities of the magnets increased as the concentration of Al-Cu increased up to 1 wt.% or up to 3 wt.% in the case of Ag-Zn. At higher concentrations the coercivities decreased markedly. The maximum gain in coercivity by the addition was about 20 %. typical values of $_{i}H_{c}$ and $B_{r}$ of a hotpressed magnet containing 1 wt.% Al-Cu were 18 kOe and 7 kG, respectively. It was found that Cu, Ag, and Zn, which diffused into the magnet during hot pressing, were mostly concentrated on the Nd-rich grain boundary phase whereas Al was present not only in the grain boundary region but also in the matrix grains.

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Cu and Zn Ions Adsorption Properties at Various pH with a Synthetic Zeolite (합성 제올라이트를 이용한 pH에 따른 Cu와 Zn 이온의 흡착특성)

  • Lee, Chang-Han
    • Journal of Environmental Science International
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    • v.21 no.7
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    • pp.805-813
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    • 2012
  • The removal property of Cu and Zn ions by chemical precipitation and adsorption using zeolite(Z-C1) prepared from coal fly ash(CFA) were evaluated in this study. Adsorption kinetic and equilibrium mechanisms described to analyze parameters and correlation factors with Lagergen $1^{st}$ and $2^{nd}$ order model and Langmuir and Freundlich model. Analysis of adsorption kinetics data revealed that the pseudo $2^{nd}$ order kinetics mechanism was predominant. The equilibrium data in pH 3 - 5 were able to be fitted well to a Langmuir model, by which the maximum adsorption capacities($q_{max}$) were determined at 124.9 - 140.1 mg $Cu^{2+}/g$ and 153.2 - 166.9 mg $Zn^{2+}/g$, respectively. We found that Z-C1 has a potential application as absorbents in metal ion recovery with low pH.

Heavy Metal Contents in Wild and Cultured Fishes from the Korean Coasts (국내 시중 유통 자연산 및 양식산 활어의 중금속 함량)

  • Mok, Jong-Soo;Shim, Kil-Bo;Lee, Tae-Seek;Song, Ki-Cheol;Lee, Ka-Jeong;Kim, Seong-Gil;Kim, Ji-Hoe
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.42 no.6
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    • pp.561-568
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    • 2009
  • We determined the contents of heavy metals in the muscle of wild and cultured fishes, collected from fish markets located in the eastern (Pohang), western (Gunsan), and southern (Tongyeong) coasts of Korea, from 2004 to 2005. As the results of monitoring the heavy metal contents in spring season, the wild fishes contained the range of Cd (0.01-0.08 mg/kg), Cr (ND-0.28 mg/kg), Cu (0.06-1.53 mg/kg), Hg (0.02-0.16 mg/kg), Mn (0.04-1.15 mg/kg), Ni (ND-0.09 mg/kg), Pb (0.03-0.41 mg/kg), and Zn (1.84-6.61 mg/kg). While for the cultured fishes, Cd (0.01-0.05 mg/kg), Cr (ND-0.17 mg/kg), Cu (0.05-0.61 mg/kg), Hg (0.02-0.13 mg/kg), Mn (0.03-0.17 mg/kg), Ni (ND-0.08 mg/kg), Pb (0.03-0.33 mg/kg), and Zn (2.06-6.20 mg/kg) were contained. In summer season, the contents of heavy metal in the muscle of the wild fishes were as follows: Cd (ND-0.11 mg/kg), Cr (0.01-0.37 mg/kg), Cu (0.21-1.31 mg/kg), Hg (0.01-0.11 mg/kg), Mn (ND-1.47 mg/kg), Ni (ND-0.26 mg/kg), Pb (0.06-0.48 mg/kg), and Zn (2.94-14.38 mg/kg). In comparison, the contents of heavy metal in the muscle of cultured fishes were Cd (ND-0.05 mg/kg), Cr (0.13-0.33 mg/kg), Cu (0.19-0.56 mg/kg), Hg (0.05-0.26 mg/kg), Mn (ND-0.14 mg/kg), Ni (ND-0.58 mg/kg), Pb (0.07-0.45 mg/kg), and Zn (2.43-7.53 mg/kg). Also the fall and the winter season, the heavy metal contents in the fishes showed almost similar with other season, however, Pb was lower and Zn was higher than both spring and summer season. The wild fishes contained the heavy metals a little more than the cultured fishes. We could not observe clear seasonal variation in the heavy metal contents of the fishes. The levels of Hg and Pb in all samples tested did not exceed the maximum permissible levels in the fishes set by the Korean Food & Drug Agency for safe human consumption.

A Study on the Heavy Metal Contents of Root Vegetables on the Retail Markets in Korea (국내에서 시판 중인 근채류의 중금속에 관한 조사 연구)

  • Kim Duck-Woong
    • Journal of the East Asian Society of Dietary Life
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    • v.15 no.4
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    • pp.465-474
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    • 2005
  • This study was conducted to estimate the contents of heavy metals 'mercury(Hg), cadmium(Cd), lead(Pb), arsenic(As), zinc(Zn), copper(Cu), chrome(Cr) and manganese(Mn)' in root vegetables which were produced in Korea. The levels of heavy metals were determined using a mercury analyzer, an ICP(inductively coupled plasma spectrometer) and an AAS(atomic absorption spectrophotometer) after wet digestion. The values of heavy metals 'mean(minimum-maximum)' mg/kg(ppm) in root vegetables (radish, turnip, carrot, ginger, edible burdock, taro, Chinese yam, east indian lotus) were as follows ; Hg : 0.0019(0.0002${\~}$0.0062), Cd : 0.0088(ND${\~}$0.0402), Pb : 0.021(ND${\~}$0.1070), As : 0.0401(ND${\~}$0.1732), Zn : 1.865(0.4186${\~}$6.9319), Cu : 0.648 (0.1826${\~}$4.0172), Cr : 0.121(0.0132${\~}$1.2030), and Mn : 2.730(0.0477${\~}$10.0468) mg/kg. These results showed that Hg were generally similar to and Cd was lower but Ph, As, Zn, Co, Mn were little higher than the levels of those reported contents in root vegetables on retail markets in Korea. Although the tolerable limit of Cd and Hg is not set in a regulation of WHO/FAO, the tested mean levels(Pb, As, Zn, Cu) were lower than the regulated ones of WHO/FAO, Pb '0.1-2.0', As '1.0', Zn '5.0', and Cu 0.1${\~}$50 mg/kg from vegetables. Therefore, root vegetables sold in the retail markets were evaluated as safe in terns of the heavy metal contents.

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Mineral Contents of Korean Apples and Apple Juices (한국산 사과와 사과주스의 무기질 함량)

  • Kim, Tae-Rang;Whang, Hea-Jeang;Yoon, Kwang-Ro
    • Korean Journal of Food Science and Technology
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    • v.28 no.1
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    • pp.90-98
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    • 1996
  • The mineral contents were analyzed for 12 varieties of Korean apples and 9 commercial apple juices by atomic absorption spectrophotometry. On the fresh matter basis, the ash contents of tested apples ranged 0.21-0.48%, Mn 0.20-2.52 ppm, Cu 0.10-1.03 ppm, Fe 0.24-9.88 ppm, Zn 0.09-1.06 ppm, Mg 21.08-99.00 ppm, Ca 15.16-99.56 ppm, K 842.10-1788.10 ppm, Na 10.32-40.53 ppm, P 24.43-90.07 ppm, Pb nd-98.05 ppb, Cd nd-36.08 ppb and Cr 2.25-123.76 ppb. Overally mineral contents of Aori and Jonathan were higher than those of Fuji. The mineral contents of apple cultivated at Wonju, Kangwon and Taegu, $Ky{\check{o}}ngbuk$ were higher than those of the other growing region. The mineral contents of commercial apple juice were ash 0.13-0.36%, Mn 0.24-0.99 ppm, Cu 0.10-0.61 ppm, Fe 0.19-3.70 ppm. Zn 0.20-1.77 ppm, Mg 18.16-49.56 ppm, Ca 14.42-42.30 ppm, K 785.07-1440.30 ppm, Na 14.71-52.58 ppm, P 16.57-63.56 ppm, Pb nd-95.55 ppb, Cd nd-17.65 ppb and Cr 8.60-110.98 ppb, respectively. Comparing mineral contents of apples and commercial apple juices, Cu, Mg, K, Ca and Fe contents of apples were higher and Zn, Na contents were lower than those of apple Juices.

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Studies on the Heavy Metal Content in Some Vegetables Sales on Market in Korea (국내에서 시판 중인 몇몇 채소류의 중금속에 관한 조사 연구)

  • Yoo Choon-Cheol;Kim Duck-Woong
    • The Korean Journal of Food And Nutrition
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    • v.18 no.3
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    • pp.254-264
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    • 2005
  • This study was conducted to estimate the contents of heavy metals 'Hg, Cd, Pb, As, Zn, Cu, Cr, Mn' in some vegetables which were produced in Korea. The levels of heavy metals were determined using a mercury analyzer, an ICP(inductively coupled plasma spectrometer) and an AAS(atomic absorption spectrophotometer) after wet digestion. The values of heavy metals "mean(mini.~maxi.)" ppm(mg/kg) in some vegetables(raw of perilla leaf, chard, small water dropwort, water dropwort, kale, bud of aralia, pumpkin(round type) and pumpkin(long type) were as follows : Hg : 0.0021(0.0006~0.0054)mg/kg, Cd : 0.0035(ND*~0.0377)mg/kg, Pb : 0.0191(0.0023~0.0928)mg/kg, As : 0.0757(ND~0.5294)mg/kg, Zn : 2.6299(0.4478~6.8567)mg/kg, Cu : 1.0261(0.2046~8.9417)mg/kg, Cr : 0.1535 (0.0240~0.4982)mg/kg, Mn : 3.2476(0.3283~9.8280)mg/kg. This results showed that Mn was generally simillar to previous reports and Cd, Hg, Pb were lower than other reseaches, but As was little higher or Zn, Cu, Cr were higher than the levels of those reported contents in some vegetables on domestic supermarkets in Korea, Although tolerable limit of Hg and Cd is not in a regulation of WHO/FAO, these mean levels(Pb, As, Zn, Cu) are lower than recommended levels of WHO/FAO, Pb "0.1~2.0" mg/kg, As "1.0" mg/kg, Zn "5.0" mg/kg and Cu "0.1~50"mg/kg from vegetables in 'the tolerable contents of food' by the FAO/WHO, therefor some vegetables has set to evaluate their safeties.

Heavy Metal Contents in Ginseng and Ginseng Products (인삼 및 인삼제품류의 중금속 함량)

  • Hu, Soo-Jung;Kim, Mee-Hye;Park, Sung-Kug;Lee, Jong-Ok
    • Korean Journal of Food Science and Technology
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    • v.37 no.3
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    • pp.329-333
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    • 2005
  • Contents of heavy metals, mercury (Hg), lead (Pb), cadmium (Cd), arsenic (As), manganese (Mn), zinc (Zn), and copper (Cu), In ginsengs and ginsengs products their safety were evaluated using a mercury analyzer, atomic absorption spectrophotometer and Inductively coupled plasma spectrometer. Contents of heavy metals in ginsengs were [min-max(mean), mg/kg]; Hg 0.002-0.02(0.007), Pb 0.018-0.39(0.106), Cd 0.004-0.413(0.106), As ND-0.094(0.013), Cu 0.24-5.5(3.2), Mn 3.18-50.4(20.09), Zn 0.76-44.27(13.42). Ginseng products values were; Hg 0.0001-0.002(0.001), Pb 0.001-0.133(0.017), Cd ND-0.07(0.004) As ND-0.181(0.008), Cu ND-1.1(0.13), Mn 0.73-30.15(1.61). Zn 0.02-13.42(1.02), similar to those reported by other countries. Average weekly Intakes of Hg, Pb and Cd from ginseng and ginseng products were 0,003, 0.01 and 0,02% of provisional tolerable weekly intake established by FAO/WHO, respectively. Our result could be utilized as important references to establish the standard of lead in ginseng and ginseng products.