A transient calorimetric technique for measuring total hemispherical emissivities ε_TH of metals at low temperatures has been improved to be more accurate and to make time-interval of measurement shorter.
The accuracy of this technique mainly depends upon the heat loss through thermocouple leads Qt. To reduce Qt, an iron-constantan thermocouple of diameter about 20μm which suspends a specimen and measures its temperature, is used, and temperature distributions of the thermocouple leads are controlled by a guard heater attached to the other sides of the thermocouple leads.
Qt evaluated by heat conduction analysis taking account of radiative heat transfer from the leads is less than 8% of the total power loss of copper thin wire, and 2% for copper thin plate.
The total hemispherical emissivity ε_TH of an annealed copper thin wire which was mechanically polished was in good agreement with the extrapolated lines from the data reported by us [22-24] at high temperatures. The annealing process reduces the ε_TH of copper. This result may be explained from conditions of surface layer: damaged surface by mechanical polishing, recrystallization and growth of crystal grain due to annealing. Reduction of the ε_TH of annealed copper may improve the performance of vacuum insulation.

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We have measured thermal diffusivity of a polyethylene composite filled with copper particles, by a laser flash method, and discussed on the effect of d/l (diameter of particle/sample thickness) on the thermal diffusivity. In the case that d/l is less than 0.3-0.4, the thermal diffusivity can be considered as an effective thermal diffusivity. The d/l (=0.3-0.4) value corresponds to the value of d/l (=0.3), at which CVF value in the electric conductivity of the polyethylene composite begins to decrease. The thermal conductivity was calculated from the thermal diffusivity measured by the laser flash method. The calculated conductivity was found to agree with the thermal conductivity which was measured by another method (steady state and comparison method). Further, our equation was found to be most excellently adaptable to the thermal conductivity of the polyethylene composites.

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This paper deals with density, specific heat and thermal conductivity of the fine capsulated latent heat storage material water mixture. The capsulalated latent heat storage material consists of the pentadecane (C₁₅H₃₂, melting point of 283.1K) and the melamine resin as the core latent heat storage material and the encapsulating material, respectively. The measured results of the mixture thermophysical properties, i.e., density, specific heat and thermal conductivity, have been discussed over the temperature region of solid and liquid phases of the core material (pentadecane). It is clarified that the additional properties law can he applied to the estimation of the density and specific heat of the mixture. Moreover it is noticed that the thermal conductivity of the mixture can be estimated by Eucken's model.

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It is necessary to know many kinds of thermophysical properties and investigate the characteristics on combustion field in order to utilize the combustion energy since the combustion of fuels is a very complex phenomena with turbulent flow field, heat transfer and chemical reactions. This paper discusses the summary and problems of combustion modeling and importance of essential thermophysical properties to estimate the combustion field.

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The oxygen transfer from blood to the living tissue has been considered from the macroscopic point of view such as Krogh's model, however, recent studies emphasized the effect of heterogeneous structure comprised of cells. The minimum oxygen partial pressure near the intima of large blood vessel appears due to the blood flow structure, and this appearance of hypoxia in the vessel is associated with the localization of atherosclerotic lesion. The oxygen transfer from the capillary to the muscle is augmented by the myoglobin, developing the steep gradient of oxygen partial pressure near the capillary and this feature of oxygen transport is different from the classic Krogh model. The oxygen transfer process in the tissue has arisen the bioengineering interests and this review article roughly surveys the some recent studies of oxygen transfer in the living tissue.

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1. Some interesting standards and draft standards of ISO and outlook of CEN organization are introduced.
2. An example of comparison of an ISO standards with the relevant ones in JIS is described to show how much difference the have and what changes are needed in JIS for the conformity with ISO.
3. How to obtain informations on TC_s. SC_s and WG of ISO and CEN is given.

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[in Japanese]

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