The magnetic field effect on the α–γ transformation of hypoeutectoid steels (Fe-0.1wt.%C, Fe-0.23wt.%C, and Fe-0.47wt.%C) were investigated by differential thermal analysis under high magnetic fields B up to 26 T. The magnetic field effects for the transformation temperatures A₁ (αFe + Fe₃C → α-Fe + γ-Fe) and A₃ (α-Fe + γ-Fe → γ-Fe) were different from each other. The increment of A₁ induced by the magnetic field was independent from the carbon concentration. A₁ increased linearly for the magnetic field for B < 10 T, whereas A₁ increased quadratically for B > 20 T. A₃ for Fe-0.23 wt.%C increased quadratically against B. When the magnetic field of 26 T was applied, A₁ and A₃ for Fe-0.47wt.%C increased 35 K and 53 K, respectively. The magnetic field effects for the A₁ and A₃ are discussed on the basis of the gain of Zeeman energy for α-Fe.

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The dilution effect of SiC on the measurement of zirconia gel powder samples by temperature programmed desorption (TPD) was investigated for the purpose of reducing the pressure in the analysis chamber of the apparatus and for obtaining sharper TPD curves similar to that of the corresponding zirconia gel film. Zirconia gel powder was added to SiC GC#1500 (Shinano Electric Refining). Mixed powder samples of 49, 59 and 81 wt% SiC were used in this study. When the samples were measured in the TPD apparatus, the pressure in the analysis chamber decreased depending on the amount of SiC added. The peak intensity and temperature of the TPD curves of the samples decreased and the peak temperature also shifted to a lower level corresponding to the SiC content. The TPD curve of a mixed powder sample of zirconia-81wt% SiC was similar to that of the zirconia gel film. These results indicated that small quantities of gases evolved uniformly from the powder, resulting in the decrease of the pressure and the peak temperature shift to a lower level. An FE-SEM analysis of the samples revealed that zirconia gel particles adhered to SiC particles.

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One of the promising methods to develop new oxide ion conductor is changing ordered oxide ion vacancy in oxide material into random one. It was reported that ordered oxide ion vacancy in Ba₂In₂O₅ and Ba₂Fe₂O₅ changed to disorder one at the structural phase transition at about 910 ºC and 850 ºC, respectively. In this report, thermal analyses of the order-disorder phase transition have been summarized. It has been clarified that enough enthalpy is absorbed at the structural phase transition of Ba₂In₂O₅ to make the ordered oxide ion vacancy arrangement completely random. It has also been revealed that the phase transition of Ba₂Fe₂O₅ involves not only order-disorder transition of oxide ion vacancy arrangement but also uptake of oxygen from gas phase, resulting in generation of cubic Ba₂Fe₂O_5+δ at higher temperature than the phase transition temperature. The higher stability of Ba₂Fe₂O_5+δ than Ba₂Fe₂O₅ at high temperature despite of higher oxidation state of Fe can be attributed to larger heat absorption accompanied with order-disorder transition than heat generation due to oxidation of Fe.

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We developed a thermophysical property evaluation instrument of the thin film in out-of-plane direction by the 2ω method. The 2ω method is based on periodic heating and thermoreflectance methods. The measurement result by the 2ω method agrees well with the calculation result on the basis of one-dimensional heat conduction model. The analysis method of the measurement result and the evaluated thermophysical property of the thin film depend on the heating frequency. The 2ω method is expected as the thermal conductivity evaluation of the thermoelectric material film.

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Temperature- and pressure-induced bilayer phase transitions of a series of diacylphosphatidylcholines containing two equivalent linear saturated acyl chains (CnPC: n = 12 – 22) were comprehensively revealed by constructing the temperature (T) – pressure (p) phase diagrams and determining thermodynamic quantities of the phase transitions, which were obtained by combined methods of differential scanning calorimetry under atmospheric pressure and light-transmittance measurements under high pressure. The T–p phase diagrams clarified various interesting aspects of the phase behavior, e.g., polymorphism between the gel phases, change in the gel-phase stability and pressure-induced bilayer interdigitation. Especially, the interdigitation was found to be induced in bilayers of CnPCs for 14 to 21. It turned out from the thermodynamic quantities that the sub-, pre- and main transition are, respectively, an acyl chain-length dependent transition with slow kinetics, an acyl chain-length independent transition with fast kinetics and an acyl chain-length dependent transition with fast kinetics, respectively. The interaction between CnPC molecules in the bilayer membrane was also deduced from the systematic consideration on the bilayer phase transitions of CnPCs.

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