The thermal constants (thermal diffusivity, specific heat, thermal conductivity) of binary oxides (Pr₂O₃-WO₃, Nd₂O₃-CuO) consisting of a mixture of rare-earth metal oxides are measured in the range of -150°C to 800°C by the laser flash method. For the oxide Pr₂O₃ WO₃, two kinds of specimens are synthesized by changing the ratio of the components Pr₂O₃ and WO₃. For the oxide Nd₂O₃-CuO, four kinds of specimens are synthesized by changing oxygen concentration during a firing, and another specimen is synthesized by doping CeO₂. The temperature dependence on the thermal constants of these specimens is investigated and the results are indicated in Figs. 5-10.

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A surface temperature distribution on a metal halide lamp bulb was measured by a thermograph whose original measuring waveband was from 2 to 5μm and limited by a narrow-band interference filter. The lamp bulb made of fused quartz was placed in a vacuum chamber to keep the operating temperature in a range from 800 to 900°C. In order to eliminate intense emission from an arc inside the bulb, the measuring wavelength was selected at an opaque region of the bulb, 4.9μm, after test measurements varying the wavelength from 3.5μm to 5.5μm. Uncertainty of the measured surface temperature was estimated to be smaller than ±15°C in a region near the center of the bulb where the angle of emission was smaller than 50°.

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[in Japanese]

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A futon is the Japanese equivalent of a mattress, which is usually filled with cotton wadding. During uses, moisture gets into the cotton fibers, and a creep of wadding occurs. Airing in the sun is a way to recover the futon, and it is a complex thermal phenomena such as radiation, heat conduction, moisture diffusion, absorption and so on. Use of a futon also causes another complex phenomena. To describe these processes by using thermophysical properties seems to be the only way to gain useful knowledge, but it has a difficulty to cope with the easy change of properties due to deformation by creep.

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This review paper deals with thermophysical properties and heat transfer phenomena of the substances in cold temperature environments. Thermal conductivity, specific heat, thermal diffusivity and thermal expansion coefficient as thermal properties and supercooling water, freezing point regression etc. as heat transfer phenomena are discussed about los temperature substances on the strength of previous works. Moreover, measuring methods of thermophysical properties under the cold temperature condition are also observed in the present review.

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Images of oxygenation state of living body can be obtained by use of time-resolved near-infrared spectroscopy based on the change in the absorption spectra of hemoglobin or myoglobin. The photon-tissue interaction is analyzed by the Monte Carlo method and the Finite Element method to solve the photon diffusion equation. The absorbance extrapolated temporally to the shortest time of flight are shown to provide a set of projection data for the reconstruction by the filtered back projection. FEM (Finite Element Method) analyses are shown to be flexible to the complex change in the distribution of the optical properties. More sophisticated procedures of the inverse problems are expected to be developed for optical-CT (computed tomography) in the near future.

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