熱測定
Online ISSN : 1884-1899
Print ISSN : 0386-2615
ISSN-L : 0386-2615
5 巻, 1 号
選択された号の論文の4件中1~4を表示しています
  • Shoji Ichihara, Tomohiko Takahama, Hideaki Nakagawa
    1978 年 5 巻 1 号 p. 2-10
    発行日: 1978/02/05
    公開日: 2009/09/07
    ジャーナル フリー
    DSC has been widely used for thermal analysis of various materials. But the methods of measurements and the reliability of the obtained data have been discussed very little. So we tried to investigate these problems from the point of view of temperature distribution in the sample and thermal balance of the sample. It was proved that the temperature distribution in the sample must be taken into consideration, even if the quantity of the sample used is small. Read out temperature diverges from the true temperature linearly with scanning rate. It is necessary to obtain the corrected base line for the measurements of heat of fusion of the materials of large temperature range of melting.
  • Yasuo Noda, Keiji Naito
    1978 年 5 巻 1 号 p. 11-18
    発行日: 1978/02/05
    公開日: 2009/09/07
    ジャーナル フリー
    The thermal conductivity of MnxFe3-xO4 with various compositions (x=0, 0.25, 0.5, 0.8, 1.0, 1.5) and hematite, and the thermal diffusivity of MnxFe3-xO4 (x=0.8, 1.0, 1.5) were measured by means of a scanning temperature method in the temperature range from 200 to 700K. An anomaly of ferrimagnetic transition was observed in the thermal diffusivity measurement for each sample, and the peak temperatures varied with the composition (x=0.8, 1.0, 1.5) were in good agreement with those observed in the permeability measurements. The anomaly was not as clearly observed in the thermal conductivity measurement as in the thermal diffusivity measurement. The measured values for thermal conductivity of MnxFe3-xO4 were so low that the phonon mean free paths calculated from the thermal conductivity data were comparable with the lattice constant. The thermal conductivity of MnxFe3-xO4 was strongly dependent on composition x and showed the maxima at the compositions with x=0 and 1.0.
  • 相分離の観測
    谷口 雅男
    1978 年 5 巻 1 号 p. 19-33
    発行日: 1978/02/05
    公開日: 2009/09/07
    ジャーナル フリー
    Conditions and ranges of stability of nonstoichiometric compounds are thermodynamically reviewed focusing the separation of phase based on the equilibrium pressure-composition isotherm. The recent precedent isotherms for the some of transition metal oxides and sulfides are chosen in this introductory paper.
    Nonstoichiometric compounds are essentially high temperature species with wide homogeneity range. At low temperature these high temperature species separate to the super structure species or the equilibrium state of two phases coexistence.
    The observations of separation of phase are very significantly for the characterization of chemical structure of solids. Especially the developments of detective technique or high resolution observation and in situ experimental proceedures will give us the much more precise informations concerning the separation of phase and a new phase with a proper crystal structure.
    The well characterized nonstoichiometric high purity compounds are very valuable in the field of material science.
  • III.マクロな状態を対象とする熱測定
    高橋 克忠
    1978 年 5 巻 1 号 p. 34-44
    発行日: 1978/02/05
    公開日: 2009/09/07
    ジャーナル フリー
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