• Title/Summary/Keyword: Levitational gas condensation(LGC)

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A study on the Particulate Properties of Ti-Ni alloy Nanopowders Prepared by Levitational Gas Condensation Method (부양가스증발응축법으로 제조된 Ti-Ni 합금 나노분말의 특성 연구)

  • Han, B.S.;Uhm, Y.R.;Lee, M.K.;Kim, G.M.;Rhee, C.K.
    • Journal of Powder Materials
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    • v.13 no.6 s.59
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    • pp.396-400
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    • 2006
  • The Ti-Ni alloy nanopowders were synthesized by a levitational gas condensation (LGC) by using a micron powder feeding system and their particulate properties were investigated by x-ray diffraction (XRD), transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET) method. The starting Ti and Ni micron powders $150{\mu}m$ were incorporated into the micron powder feeding system. An ingot type of the Ti-Ni ahoy was used as a seed material for the levitation and evaporation reactions. The collected powders were finally passivated by oxidation. The x-ray diffraction experiments have shown that the synthesized powders were completely alloyed with Ti and Ni and comprised of two different cubic and monoclinic crystalline phases. The TEM results showed that the produced powders were very fine and uniform with a spherical particle size of 18 to 32nm. The typical thickness of a passivated oxide layer on the particle surface was about 2 to 3 nm. The specific surface area of the Ti-Ni alloy nanopowders was $60m^2/g$ based on BET method.

The study of Synthesis of Dihydropyrimidine for Cardiotropic Drugs Using New Catalysts on the Basis of Nano Cu Oxides (신촉매 나노 구리산화물을 이용한 심혈관 의약품용 Dihydropyrimidine 제조 연구)

  • Uhm Y. R.;Lee M. K.;Rhee C. K.
    • Journal of Powder Materials
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    • v.12 no.6 s.53
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    • pp.441-446
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    • 2005
  • The copper oxide nano powders were synthesized by levitational gas condensation (LGC) method, and were applied to catalyst to fabricate 3,4-dihydropyrimidin-2-(1H)-one. Processes of adsorption of Biginelli reaction reagents on the copper nanooxide surface $Cu_2O{\circ}CuO$ were studied by IR-spectroscopy. It was shown that benzaldehyde coordination, acetoacetic ether on the oxide surface is carried out with participation of carbonyl fragments, urea by N-H bonds which affects positively on the reagents reactivity.

Effect of Alumina Nanooxide Application on Nitrendipine Manufacturing Process (알루미나 나노산화물이 Nitrendipine 제조 공정에 미치는 영향)

  • Chae, E.J.;Uhm, Y.R.;Han, B.S.;Rhee, C.K.;Park, S.E.
    • Journal of Powder Materials
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    • v.14 no.2 s.61
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    • pp.127-131
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    • 2007
  • The alumina nano powders synthesized by levitational gas condensation (LGC) method were applied to catalyst in manufacturing process of Hanzsch reaction for Nitrendipine. The L-tartaric acid on the surface is carried out with participation of carbonyl fragments, O-H, C-H bonds which affects stereo selectivity, yield on the reagents positively. From the analysis of the IR-spectroscopy, the carbonyl fragments, O-H, and C-H bond were created by the catalytic reaction. From the analysis of the rR-spectroscopy, the carbonyl fragments, O-H, and C-H bond were created by the catalytic reaction. The newly created bonds made a chiral center on the final product.