The authors found that liquid Cu droplet wetted and spread very widely on a solid substrate of Fe in a reduced atmosphere after the surface oxidation of the substrate. In this study, the wetting behavior of liquid metals (mainly In) to porous layer formed on the iron substrate, which had been prepared by the oxidization and the reduction, was investigated. The morphologies of the porous layer, which were formed on the surface of the iron substrate treated with the oxidation-reduction process, are dependent on the atmospheres (H₂ or Ar) that were used during heating up to various reduction temperatures. The unusual wetting phenomenon of liquid In occurred in all of the iron samples which had been prepared by the oxidation-reduction process. Those results show that pores in the porous layer connect each other in three dimensionally. Liquid Cu, which has a small solubility in Fe, also penetrated into the porous layer. Porous Cu thin film was fabricated by removing the Fe substrate.

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PWFA recycled composite, which is made mostly from plastic waste and fly ash, is one of the materials developed for the purpose of recycling. The authors observed the cutting surface of the composite using a metalloscope and measured the thermal conductivity of the composite using two guarded hot plate apparatus suitable for the different sizes of specimen 100×100 and 50×50 mm² in area.
The spherical particles of fly ash disperse at irregular intervals in the matrix. The matrix composed of the plastic waste and the fire retardant is the continuous phase. And there is a dense area of voids inside the specimen. The thermal conductivity decreases from 0.44 to 0.38 W · m^-1 · K^-1 with increasing the specimen temperature from 250 to 350 K. The data for the specimen 50×50 mm² are lower than those for the specimen 100×100 mm², but agree with those for the specimen 100×100 mm² within 5%.

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The gaseous diffusion coefficients of dimethyl ether (CH₃OCH₃, DME) and diethyl ether (C₂H₅OC₂H₅, DEE) into air, nitrogen and oxygen have been measured in the temperature range 303∼453 K and at atmospheric pressure by the use of the Taylor dispersion method. Both for DME and DEE, the diffusion coefficients do not vary in practice on substituting pure nitrogen or oxygen for air. The diffusion coefficients for DEE are systematically smaller than those for DME by about 35%. The present results can be reproduced well by the functional form D/cm²s^-1 = A (T/K)^B, where D is the diffusion coefficient at 101.325 kPa (1 atm) and T is the absolute temperature. The constants A and B are as follows: DME- (air, nitrogen, oxygen), A = 6.61×10^-6, B = 1.75; DEE- (air, nitrogen, oxygen), A = 3.56×10^-6, B = 1.78.

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Vapor-liquid equilibrium behaviors of 5-hydroxymethylfurfural in methanol, ethanol, and water were measured at atmospheric pressure in the dilute composition range of 5-hydroxymethylfurfural with a recirculation still. Vapor-liquid equilibrium behaviors of citric acid in methanol and ethanol were further measured. Equilibrium compositions were determined with an ultraviolet spectrometer. The volatilities of 5-hydroxymethylfurfural at infinite dilution were determined to be 0.0020, 0.0026, and 0.012, respectively, in methanol, ethanol, and water. The volatilities of citric acid at infinite dilution were determined to be 0.0008 and 0.0012, respectively, in methanol and ethanol.

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