• Title/Summary/Keyword: Molybdenum

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Preparative and Thermal Studies of Tris (8-hydroxyquinolino)molybdenum (III) (Tris(8-hydroxyquinolino) molybdenum (III)의 합성과 열적 성질에 관하여)

  • Choi, Q. Won;Oh, Joon-Suk;Lee, Kwang-Woo;Lee, Won
    • Journal of the Korean Chemical Society
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    • v.12 no.4
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    • pp.146-149
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    • 1968
  • A new chelate compound, tris(8-bydroxyquinolino)molybdenum(III), [$Mo(C_9H_6ON)_3$], has been prepared by the method of electrolytic reduction of the acidic molybdate solution. Thermal decomposition products of the chelate has been studied by DTA and TGA method. It is concluded that the decomposition product is a yellowish green colored bis(8-hydroxyquinolino)dioxo molybdenum(VI), [$MoO_2(C_9H_6ON)_2$].

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Geochemical Correlations Between Uranium and Other Components in U-bearing Formations of Ogcheon Belt (옥천대(沃川帶) 함(含)우라늄지층중(地層中)의 우라늄과 타성분(他成分)과의 상관관계(相關關係))

  • Lee, Min Sung;Chon, Hyo Taek
    • Economic and Environmental Geology
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    • v.13 no.4
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    • pp.241-246
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    • 1980
  • Some components in uranium-bearing formations which consist mainly of black shale, slate. and low grade coal-bearing formation of Ogcheon Belt were processed statistically in order to find out the geochemical correlations with uranium. Geochemical enrichment of uranium, vanadium and molybdenum in low grade coal-bearing formations and surrounding rocks is remarkable in the studied area. Geochemical correlation coefficient of uranium and molybdenum in the rocks displays about 0.6, and that of uranium and fixed carbon about 0.4. Uranium and vanadium in uranium-bearing low grade coals denote very high correlation with fixed carbon, which is considered to be responsible for enrichment of metallic elements, especially molybdenum. Close geochemical correlation of uranium-molybdenum couple in the rocks can be applied as a competent exploration guide to low grade uranium deposits of this area.

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Characteristics of Microstructure of Hardfacing Layer of Stellite 6 with Mo Addition (몰리브덴을 첨가하여 PTAW법으로 육성된 Stellite 6합금의 미세조직 특성평가)

  • 신종철;김재수;이덕열;양재웅;윤진국;노대호;이종권
    • Journal of the Korean institute of surface engineering
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    • v.35 no.4
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    • pp.241-248
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    • 2002
  • Hardfacing layers of Stellite 6 alloy with different molybdenum content are deposited on AISI 1045 carbon steel using plasma transferred arc welding (PTAW). The properties of the hardfacing layer are investigated in order to clarify the effect of molybdenum addition to the cobalt-base alloy. With an increase in molybdenum contents, the size of Cr-rich carbides in the interdendritic region is abruptly refined, but volume fraction of the carbide slightly increases. Also, with an increase of Mo, $M_{6}$ C type carbides are formed instead of Cr-rich $M_{7}$ $C_{3}$ type carbided, and this microstructural change enhanced the mechanical properties of Stellite 6 alloy.

The Effects of Molybdenum Content on the Dynamic Properties of Tungsten-based Heavy Alloys

  • Lee, Woei-Shyan;Chan, Tien-Yin
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09b
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    • pp.1155-1156
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    • 2006
  • Hopkinson bar dynamic test under strain rates ranging from 2000 $s^{-1}$ to 8000 $s^{-1}$ at room temperature revealed that the flow stress of tungsten heavy alloys depended strongly on the strain, strain rate, and the content of molybdenum. The variation of flow stress was caused by the competition between work hardening and heat softening in the materials at different strain rates. The high temperature strength of the matrix phase was increased by the addition of molybdenum, which enhanced the strength of the tungsten heavy alloys in high strain rate test.

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Synthesis and Characterization of Molybdenum(V) Complexes with Tridentate Schiff Bases

  • Jung Sook Kim;Bon Kweon Koo
    • Bulletin of the Korean Chemical Society
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    • v.13 no.5
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    • pp.507-511
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    • 1992
  • Six-coordinate molybdenum(V) complexes X[MoO$(NCS)_2$(L)], where X=$PyH^+$, $Me_4N^+$, $Et_4N^+$, n-$Bu_4N^+$, and L= the tridentate schiff base dianions derived from the condensation reaction between various salicylaldehydes and 2-aminophenol have been synthesized. The complexes have been characterized by elemental analysis, conductivity, UV-visible, IR, $^1H$-NMR, and mass spectroscopy. The coordination around the molybdenum appears to be distorted octahedral. A tridentate ligand containing the ONO donor atoms occupies meridional positions with the N atom trans to the terminal oxo group. Two NCS ligands bond to the molybdenum through the N atom and are cis to the Mo = $O_t$ group. The electrochemical behaviors of the complexes have also been investigated by cyclic voltammetry in dimethylsulfoxide.

Molybdenum Dialkyl Dithiocarbamate의 摩擦特性

  • 김영환;김형자;김정곤
    • Tribology and Lubricants
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    • v.6 no.1
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    • pp.68-73
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    • 1990
  • 본 논문은 油溶性 몰리브덴系 化合物 중 Molybdenum dialkyl dithiocarbamate(以後 MoDTC로 略함)를 潤滑油 添加濟로 사용해 摩擦實驗을 통하여 마찰감소 작용의 메카니즘을 解明하고 특히 마찰표면에 생성될 MoS$_2$ 막의 효과에 관해 중점을 두고 雰圍氣의 효과로부터 MoDTC의 마찰감소작용의 인자에 대한 고찰을 행하였다.