• 제목/요약/키워드: MnAl

검색결과 1,114건 처리시간 0.027초

BCC계 Ti-Cr-V 합금의 전기화학적 특성에 미치는 Mn 및 $AB_5$계 합금 첨가 효과 (Effects of the Addition of Mn and $AB_5$ Type Alloy on the Electrochemical Characteristics of Ti-Cr-V BCC Type Alloys)

  • 김종연;유정현;박충년;박찬진;최전;조성욱
    • 한국수소및신에너지학회논문집
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    • 제18권1호
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    • pp.52-59
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    • 2007
  • We investigated the effects of the addition of Mn and $AB_5$ type alloy on the electrochemical characteristics of Ti-Cr-V BCC type alloys as anode materials for Ni-MH battery. The activation behavior and discharge capacity of the BCC type alloys were significantly improved by ball-milling with the $LmNi_{4.1}Al_{0.25}Mn_{0.3}Co_{0.65}$ alloy, because the $AB_5$ type alloy acted as hydrogen path on the surface of the BCC type alloy. Among the Mn substituted alloys($Mn=0.03%{\sim}0.08%$), the $Ti_{0.32}Cr_{0.38}Mn_{0.05}V_{0.25}$ alloy ball-milled with $AB_5$ type alloy exhibited the greatest discharge capacity of $336\;mAh{\cdot}g^{-1}$. In addition, Mn substituted alloys exhibited the lower plateau pressure in P-C- T curve, the better hydrogen storage capacity and faster surface activation compared with the alloy without Mn.

Removal of Heavy Metals by Cladophora sp. in Batch Culture: The Effect of Wet-mixed Solidified Soil (loess) on Bioremoval Capacities

  • Kim, Jin-Hee;Lee, Kyung-Lak;Kim, Sook-Chan;Kim, Han-Soon
    • 생태와환경
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    • 제40권4호
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    • pp.537-545
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    • 2007
  • The heavy metal removal capacity of filamentous green alga Cladophora sp. cultured together with wet-mixed solidified soil (loess) was tested. A Cladophora sp. was cultured for 5d, with added Chu No. 10 medium, in stream water contaminated by high concentration of heavy metals from a closed mine effluent. Heavy metal ion concentrations of the medium and in algal tissue were measured every day during the experiment. Dissolved metals (Al, Cd, Cu, Fe, Mn, Zn) in medium were rapidly removed (over 90% elimination) within 1-2d when alga and loess were added. Dissolved heavy metals dropped by only 10% when algae were cultured without loess. The Cladophora sp. accumulated much more heavy metals when cultured with loess than when the alga was cultured alone. Cladophora sp. exhibited a maximum uptake capacity for Al ($17,000{\mu}g^{-1}$ algal dry weight). The metal bioremoval capacities of the algae were in the order Al, Fe, Cu, Mn, Zn and Cd. The heavy metal removal capacity of Cladophora sp. showed significant increases when wet-mixed solidified soil was added to culture media.

제주도 대기 분진 중 미량금속의 농도 특성 (Trace Metals in Airborne Particulates Collected at Cheju Island, Korea)

  • 최만식;박은주
    • 한국대기환경학회지
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    • 제15권6호
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    • pp.727-738
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    • 1999
  • Total 76 aerosol samples were collected at Sungsan in Cheju Inland by high volume air sample for 1 year, from May 1995 to April 1996, and were analyzed for major elements(Na, Mg, Ca, Al, Fe) and trace elements(Mn, Co, Ni, Zn, Cd, Pb, U) by ICP/AES and ICP/MS. This study aims to determine the concentrations of trace metals and their seasonal variations in the atmosphere of Cheju Island, where is the remote area from pollution sources and also is the midway of transport of Asian continental materials into the western North Pacific. The concentrations of Na and Mg contributed by sea-salt aerosols were similar to those in the western part of Cheju island(Kosan) and in the western coast of Korea(Mallipo). They showed the highest value in summer and the lowest in spring and winter. Crustal metals(Al, Fe, Ca, Mn, Co, U) were 2~3 times lower than those of Mallipo. These metals showed the lowest values in summer and the highest in spring. Pollution-derived metals (Zn, Cd and Pb) were 2~4 times lower than those in Malipo. Some elemental ratios in aerosols grouped by three wind directions(north-northwest, east, and south-southwest) such as Fe/Al and Pb/Zn are presented as useful tracers indicating source areas, and their differentiation may be explained by geology and fuel types of source areas.

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Removal Efficiency of Arsenic by Adsorbents having Different Type of Metal Oxides

  • Min, Sang-Yoon;Kim, Byeong-Kwon;Park, Sun-Ju;Chang, Yoon-Young;Yang, Jae-Kyu
    • Environmental Engineering Research
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    • 제14권2호
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    • pp.134-139
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    • 2009
  • In this study, oxidation of As (III) as well as removal of total arsenic by adsorbents coated with single oxides or multi-oxides (Fe (III), Mn (IV), Al (III)) was investigated. In addition, multi-functional properties of adsorbents coated with multi-oxides were evaluated. Finally, application of activated carbon impregnated with Fe or Mn-oxides on the treatment of As (III) or As (V) was studied. As (V) adsorption results with adsorbents containing Fe and Al shows that adsorbents containing Fe show a greater removal of As (V) at pH 4 than at pH 7. In contrast adsorbents containing Al shows a favorable removal of As (V) at pH 7 than at pH 4. In case of iron sand, it has a negligible adsorption capacity for As (V) although it contains 217.9 g-Fe/kg-adsorbent, Oxidation result shows that manganese coated sand (MCS) has the greatest As (III) oxidation capacity among all metal oxides at pH 4. Oxidation efficiency of As (III) by IMCS (iron and manganese coated sand) was less than that by MCS. However the total removed amount of arsenic by IMCS was greater than that by MCS.