• 제목/요약/키워드: Solid-State Reaction

검색결과 853건 처리시간 0.037초

La-Ni-O계 화합물의 상전이 및 전기전도도에 관한 연구 (Phase Transition and Electrical Conductivity of La-Ni-O System)

  • 변재동;김진관;김세호;송기영
    • 한국세라믹학회지
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    • 제29권1호
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    • pp.41-47
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    • 1992
  • Phase transition and electrical conductivity of homologous series phases Lan+1NinO3n+1 (n=1,2,3, …, $\infty$) have been investigated. These La-Ni-O chemical compounds were synthesized by solid state reaction. The compound LaNiO3 was thermally stable in air only up to about 1120 K and above this temperature decomposed into homologous series phases Lan+1NinO3n+1 and NiO.

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초음파 분무 열분해법에 의한 $(Zr, SN)TiO_4$ 구형 미분말의 합성 (Preparation of Spherical (Zr, Sn)TiO4 Powders by Ultrasonic Spray Pyrolysis)

  • 조서용;이종흔;김명철;박순자
    • 한국세라믹학회지
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    • 제31권5호
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    • pp.465-470
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    • 1994
  • Fine, spherical (Zr, SN)TiO4 powders were prepared from the aqueous solution of metal chlorides by ultrasonic spray pyrolysis. Single phase (Zr, SN)TiO4 powders could be obtained above $700^{\circ}C$ (=temperature of the reactor) and all powders exhibited sizes in the range of 0.1 to 2.0 ${\mu}{\textrm}{m}$ and a narrow size distribution. The sintering properties of the prepared powders were better than those of the powders from solid-state reaction.

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Hydrothermal synthesis and photoluminescence properties of nanocrystalline $GdBO_3:Eu^{3+}$ phosphor

  • Kim, Tae-Hyung;Kang, Shin-Hoo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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    • pp.717-720
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    • 2005
  • Nanocrystalline $GdBO_3:Eu^{3+}$ was prepared by a hydrothermal method. The as-synthesized powders were spherical shaped agglomerates of nano particles. The luminescent properties were compared with samples synthesized by conventional solid-state reaction method. Both the photoluminescence intensity and chromaticity were improved and a red-shift in the CT band was observed for the hydrothermally synthesized samples.

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초음파 에너지가 mn-Zn Ferrite 분체에 미치는 영향 (Effects of Ultrasonic Energy on Mn-Zn Ferrite Powder Behavior)

  • 이경직;이대희;이석기;이병교
    • 한국세라믹학회지
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    • 제36권7호
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    • pp.751-755
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    • 1999
  • Effect of ultrasonic-wave irradiation on the Mn-Zn ferrite powder suspension prepared by solid-state reaction and alcoholic dehydration methods was investigated. Size distribution and morphology of the powders prepared at different temperature were examined as a function of irradiation time. It was observed that the powders were reduced in size by ultrasonic energy through distinct routes.

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PNN-PZN-PZT계 세라믹의 압전 및 유전특성 (Dielectric and Electric Properties of Ceramics PNN-PZV-PZT)

  • 이수호;손무헌;사공건
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1994년도 하계학술대회 논문집 C
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    • pp.1271-1273
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    • 1994
  • In the field of the optics, precise machine, semiconducting processing, the micro-positioning actuators are required for the control of position in the submicron range. In this study, PNN-PZN-PZT ceramics were fabricated by solid state reaction. The structural, dielectric and electric properties were investigated for sintering condition. The specimen sintered for 1hr at 1,150($^{\circ}C$), had the highest density and dielectric contant.

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Chemical Reactions in Solid State Complexes of 1,2-Polybutadiene and Palladium Chloride : High Temperature Infrared Study

  • Lee, Joon Y.;Laurence A. Belfiore
    • Bulletin of the Korean Chemical Society
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    • 제17권9호
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    • pp.826-830
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    • 1996
  • Fourier transform infrared (FTIR) temperature studies were performed to examine the microstructural changes that occur in annealing process of the thin films of 1,2-polybutadiene (1,2-PBu)/palladium chloride (PdCl2) complex. The disappearance of the infrared absorption intensities at 1640, 1418, 994 and 910 cm-1 signifies the consumption of 1,2-vinyl groups of 1,2-PBu. The progressive loss of unsaturation and production of methyl groups as a function of temperature were identified by the enhanced infrared absorption intensities at 1447 and 1375 cm-1. The loss of pendent carbon-carbon double bond is considered to involve both palladium-catalyzed addition reaction and thermally induced cyclization.

Soft Solution Processing : Low-Energy Direct Fabrication of Advanced Inorganic Materials

  • Masahiro Yoshimura;한규승;Wojciech Suchanek
    • Bulletin of the Korean Chemical Society
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    • 제20권8호
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    • pp.875-878
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    • 1999
  • A new concept ??soft solution processing?? has been introduced to fabricate advanced solid state materials in an economical, environmentally friendly, and energy and material efficient way. The prepared films show the desired and prospective properties despite of low temperature synthesis and no post-synthesis annealing. Successful examples demonstrate that soft solution processing is capable of preparing advanced materials with planned properties through the easy control of reaction conditions in a suitable aqueous solution in a single synthetic step without huge energy consumption and without any sophisticated equipment.