The directional transmittance and reflectance of carbon fiber-sheet (CF-sheet) being in effective use as collecting materials for an air-type solar collector were measured for the normal incidence of radiation beam from three kinds of light sources; laser beam, tungsten lamp and nichrome-wire. As a result, the directional transmittance of the CF-sheet was projected in the propagating direction of an incidence (φ=0°). The sum of the hemispherical transmittance and reflectance was largest for the light source of the laser, medium for the tungsten and smallest for the nichrome-wire.

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A precise thermal expansion measurement system which covers the temperature region from 250 to 360K and measurement results of five low expansion materials (silicon, fused silica SRM739, inver alloy, low expansion ceramic and low expansion glass) are presented. At the present work, an air thermal bath has been incorporated with the double path optical heterodyne interferometer.
The present results of silicon, fused silica and low expansion glass agree very well with the recommended data and other precise data previously reported. The maximum deviations among these data are within 3×10^-8/K.

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The method for measurements of the thermal conductivity of refractories, insulating bricks and structural ceramics, and these standardization in the world were reviewed briefly, relating progress in materials and techniques to the developments in the high temperature industry.
The thermal conductivity of refractories was measured by a panel method which operates with the specimen under a temperature gradient simulating service conditions in the U.S. In 1947, the method was adopted as ASTM C-182, C-201, and C-202. Recently, a transient hot wire (THW) method was adopted as ASTM C-1113.
In Germany, the Didier Research Institute for DIN committee (DRI) selected the THW method as DIN 51046.
There exist the BS 2973 and BS 1902 using a modified ASTM method in the Great Britain. The THW method was tested at British Ceramic Research Association (BCRA).
In France, There isn't standard test method. The Paris institute of the Société Francaise de Céramique (SFC) has compared différent methods such as ASTM, a radial flux and the THW method. After SFC, BCRA and DRI agreed that the THW method (DIN 51046) was to be recommended to the International Organization for standrdization and the THW method was adopeded as ISO 8894-1 in 1987 and 8894-2 (parallel method) in 1990.
In Japan, the ASTM method with reduced test specimen for insulating bricks has been issued as JIS R 2616 in 1959. The apparatus for measuring thermal conductivity of insulating bricks by the THW method was adopted as JIS R 2618, and improved in 1991. There is no standard test method for refractories bricks yet, because it is very difficult to select any method for thermal conductivity measurements of high conductive bricks. In 1991, a laser frash method was adopeted as JIS R 1611 for measuring the thermal conductivity of structural fine ceramics.

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Ceramic-fibrous thermal insulations show very low effective thermal conductivities. Heat transfer characteristics of the insulations change largely with increasing packed density by compression, because contact points between fibers are not fixed. This article introduces an heat transfer model which can predict the effective thermal conductivity on the basis of internal structure of the insulations.

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The fundamental concepts and theories of diffusion for liquids are described. The applications of these theories to diffusion of liquids in high temperatures are introduced in particular emphasis on liquid metals and fused salts. Importance is stressed on the combination of space diffusion experiment, computer experiment and theoretical study for advances of the study of diffusion in liquid state.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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