Thermal properties of water and benzene confined within silica-gel mesoporous materials MCM-41 and SBA-15 were investigated by adiabatic calorimetry. Confined water crystallized at low temperature while forming a boundary water layer of an amorphous state. The layer buffered the water content which is located in internal part of the pore from the effect of the pore wall, and kept it like bulk water. Confined benzene was affected by the presence of the pore wall. The configuration entropy S_conf of confined benzene in a liquid state decreased with decreasing a pores size. Crystallizations of both liquids were inhibited when they were confined within small pores of certain pore diameters, respectively. Both liquids confined within such small pores became stabilized at low temperature in different ways, respectively.

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Here, our recent study on the oxygen-storage materials BaLnMn₂O_5+δ with Ln = La, Nd, Gd, and Y is reviewed. The redox characteristics of these materials were systematically investigated employing the reductive water dissolution by the deoxygenated δ = 0 form. The Ln = La, Nd, and Gd compounds were found to show a capability to produce hydrogen gas through the water dissolution at 500 °C, whereas the Ln = Y compound was unreactive to water. The present study also revealed that the reactivity significantly depends on the Ln species: the larger the Ln³⁺ ionic size, the higher reactivity the BaLnMn₂O_5.0 samples exhibit. The experimental data were discussed on the basis of thermodynamic energetics by quantum chemical calculations.

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The orthorhombic-tetragonal structural phase transition behaviors of Pr₂NiO_4+δ and Nd₂NiO_4+δ were investigated by DSC and TG–DTA under controlled oxygen partial pressure, P(O₂), and their difference was discussed. Endothermic peak corresponding to the structural phase transition was observed in DSC curves. The transition temperature, T_p, decreases with decreasing P(O₂) both in Pr₂NiO_4+δ and Nd₂NiO_4+δ. A discrete weight variation originating from the variation of oxygen content, Δδ, was observed during the phase transition both in Pr₂NiO_4+δ and Nd₂NiO_4+δ. The Δδ of Pr₂NiO_4+δ was larger than that of Nd₂NiO_4+δ, and the Δδ of Pr₂NiO_4+δ increased with decreasing P(O₂), while that of Nd₂NiO_4+δ was independent on P(O₂), suggesting that not only the valence of Ni but also that of Pr changed during the phase transition in Pr₂NiO_4+δ. From the Ellingham diagram prepared using T_p measured by DSC under various P(O₂), ΔH° and ΔS° at the phase transition were evaluated. It was revealed that ΔH° of Nd₂NiO_4+δ is larger than that of Pr₂NiO_4+δ, whereas ΔS° shows little difference, showing agreement with higher T_p of Nd₂NiO_4+δ that that of Pr₂NiO_4+δ.

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To improve the thermal conductivity of epoxy resin without losing the insulation, epoxy/silicon nitride (Si₃N₄) nanowire composites were produced. β-Si₃N₄ nanowires were synthesized by the carbothermal reduction and nitridation of a homogeneous mixture of silica (SiO₂), carbon, and a small amount of cobalt via the vapor–liquid–solid (VLS) mechanism. The ratio of β to α phase in the product Si₃N₄ increased with heat-treatment temperature; however, the undesirable SiC also increased. By increasing the nitrogen gas pressure in the heat treatment, the ratio of β- to α-Si₃N₄ increased without producing SiC. The epoxy composite containing Si₃N₄ nanowires of 60 vol.% showed high thermal conductivity of 9.2 Wm^-1K^-1 along the preferred orientation of the nanowires.

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