• Title/Summary/Keyword: Iron pentacarbonyl

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Transition Metal Catalyzed the Double Hydrohydroxymethylation of Carbonyl Compounds by a Carbon Monoxide-Water System (전이금속촉매-일산화탄소-물계에 의한 카르보닐화합물의 이중 히드로히드록시메틸화 반응)

  • Sang Chul Shim;Kyung Eun Min;Keun Tae Huh
    • Journal of the Korean Chemical Society
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    • v.30 no.1
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    • pp.101-104
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    • 1986
  • Dialdehydes such as adipaldehyde, glutaraldehyde, and succinaldehyde were readily reduced to give their corresponding 1,6-hexanediol, 1,5-pentanediol, and 1,4-butanediol in good yields in the presence of catalytic amount of hexarhodium hexadecacarbonyl or iron pentacarbonyl in water and methoxyethanol or ethanol at 180$^{\circ}C$ for 4 hr under carbon monoxide atmosphere. Under the same reaction conditions, diketones such as 2,5-hexanedione, 2,4-pentanedione, and 2,3-butanedione afforded their corresponding 2,5-hexanediol, 2,4-pentanediol and 2,3-butanediol in moderate yields. For double hydrohydroxymethylation of dialdehydes or diketones, rhodium or iron carbonyl complexes are more effective than others. Particularly, benzoquinone gave hydroquinone quantitatively.

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Synthesis and Characteristics of FePt Nanopowder by Chemical Vapor Condensation Process

  • Yu, Ji-Hun;Lee, Dong-Won;Kim, Byoung-Kee;Jang, Tae-Suk
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09b
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    • pp.1196-1197
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    • 2006
  • FePt binary-alloy nanopowder has been successfully synthesized by chemical vapor condensation process with two metal organic precursors, i.e., iron pentacarbonyl and platinum acetylacetonate. Average particle size of the powder was less than 50 nm with very narrow size distribution, revealing high dispersion capability. Characteristics of the powder could be controlled by changing process parameters such as reaction temperature, chamber pressure, as well as gas flow rate. Magnetic properties of the synthesized FePt nanopowder were investigated and analyzed in terms of the powder characteristics.

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Preparation of Poly(vinylpyrrolidone) Coated Iron Oxide Nanoparticles for Contrast Agent (조영제로 활용하기 위한 폴리(비닐피롤리돈)이 코팅된 산화철 나노 입자의 제조)

  • Lee Ha Young;Lim Nak Hyun;Seo Jin A;Khang Gilson;Kim Jungahn;Lee Hai Bang;Cho Sun Hang
    • Polymer(Korea)
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    • v.29 no.3
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    • pp.266-270
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    • 2005
  • Iron oxide nanoparticles were prepared by the thermal decomposition of iron pentacarbonyl (Fe(CO)$_5$) Poly(vinylpyrrolidone) (PVP) was used as surface-modifying agent to control the size of the iron oxide nanoparticles. The crystalline structure of PVP coated iron oxide nanoparticles was determined by XRD. The size of PVP coated iron oxide nanoparticles was determined by TEM and ELS. The particle sizes of PVP coated iron oxide nanoparticles were controlled by adjusting the molar ratio of PVP/Fe (CO)$_5$, solvent and molecular weight of PVP Particle sizes increased with increasing PVP content. Spherical $50\~100$ nm sized iron oxide nanoclusters were produced when dimethylformamide was used as a solvent. And well-defined 10 nm iron oxide nanoparticles were produced in Carbitol. The prepared PVP coated iron oxide nanoparticles exhibited a well-dispersed property in water. The results obtained in this study confirmed the feasibility of the PVP-coated iron oxide nanoparticles as a biomaterial for MRI contrast agent.

Double Convective Assembly Coatings of FePt Nanoparticles to Prevent Particle Coalescence during Annealing

  • Hwang, Yeon
    • Korean Journal of Materials Research
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    • v.21 no.3
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    • pp.156-160
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    • 2011
  • FePt nanoparticles suspension was synthesized by reduction of platinum acetylacetonate and decomposition of iron pentacarbonyl in the presence of oleic acid and oleyl amine. FePt nanoparticles were coated on a substrate by convective assembly from the suspension. To prevent the coalescence during the annealing of FePt nanoparticles double convective coatings were tried. First convective coating was for silica particle assembly on a silicon substrate and second one was for FePt nanoparticles on the previously coated silica layers. It was observed by scanning electron microscopy (SEM) that FePt nanoparticles were dispersed on the silica particle surface. After annealing at $700^{\circ}C$ for 30 minutes under nitrogen atmosphere, FePt nanoparticles on silica particles were maintained in a dispersed state with slight increase of particle size. On the contrary, FePt nanoparticles that were directly coated on silicon substrate showed severe particle growth after annealing due to the close-packing of nanoparticles during assembly. The size variation during annealing was also verified by X-ray diffractometer (XRD). It was suggested that pre-coating, which offered solvent flux oppose to the capillary force between FePt nanoparticles, was an effective method to prevent coalescence of nano-sized particles under high temperature annealing.