The forced Rayleigh scattering method has many unique characteristics which are lacking in other conventional methods for the measurement of the thermophysical properties. By this optical method, the thermal diffusivity can be measured within 1ms, by a volume of about 10mm³ and in a contact-free manner. In the present paper, we demonstrate the promising applicability of this method to the measurements of liquid crystal and high-temperature molten salts.

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Thermophysical properties of intermetallic compound TiAl have been examined in the temperature range 300 to 900K under a vacuum of 1mPa. TiAl is an intermetallic compound of metallic side whose crystal structure contains about 30% covalent bonding. The measuring method employed in this study is the direct electrical heating method improved for the simultaneous measurement of thermal expansion, electrical resistivity, total hemispherical emissivity, specific heat, and thermal conductivity. Rectangular rod samples (1.22×8.02×110mm) of Ti-34wt%Al intermetallic compound are used. The specific heat is determined by measuring the temperature change of the sample resulting from a step-wise current change. The thermal conductivity is obtained from measuring the temperatures at three points of the steady-state temperature-distribution caused by the passage of a constant current without auxiliarily heating both sample holders. Some of the results are compared with the literature values of Titanium base alloy (Ti6Al-4V). The uncertainties of the obtained data of specific heat and thermal conductivity are estimated to be 4.5 and 5.5%, respectively. From these results, the influence of the existence of covalent bond in the crystal structure of TiAl on the thermophysical properties is found to be about 20% in this temperature range.

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We calculated mesurement error in guarded hot plate method to be based on Woodside equation. And the relations between scattering of thermal conductivity mesurement and water content, diameter of fiber, shot content and density in building materials are presented.

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[in Japanese]

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[in Japanese]

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Recently, industries have frequently dealt with mixtures which exhibit a drastic change in phase states in compliance with operation conditions of processes. Such phase behavior including a kind of phase equilibria has not yet been properly investigated. In this paper, a classification for phase behavior is discussed for purpose of predicting phase behavior of binary mixtures.

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The present studies on physical and chemical properties of environmentally acceptable fluorocarbons are reviewed briefly. Updated informations on ODP, GWP, toxicity and flammability are listed for CFCs, Halons, HCFCs and HFCs in Table 1. The necessity of measurements on thermophysical properties for mixtures is stressed.

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[in Japanese]

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[in Japanese]

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