In this study, we measured by DSC the latent heat of fusion of ice in various starches (A-type crystalline structure; corn starch, rice starch, waxy corn starch, and glutinous rice starch, B-type crystalline structure; potato starch) whose moisture contents were adjusted to 50%, immediately after and a few days after the high pressure treatment of 600MPa, or after the heat treatment of 80°C and 120°C. We examined the state of the water in the starch-water systems through the comparison of the DSC curves.
The results were as follows: according to the thermograms of the starch-water systems after the high pressure treatment, the endothermic heat flows of starches of A-type crystalline structure varied more greatly than those of B-type crystalline structure, whereas, according to the thermograms of the starch-water systems after the heat treatment, starches of B-type crystalline structure were more strongly affected by heat. Regardless of the kind of starch, starch-water systems subjected to high pressure treatment showed peaks at round 0°C in the thermograms, which shows that the water component in the starches in mainly free water. On the other hand, the peaks of the thermograms of the starch-water systems subjected to heat treatment were under 0°C, which shows that the water component in the starches includes more restricted water. In addition, the waxy starches (waxy corn starch, and glutinous rice starch), which are considered to have high crystallinity, showed that the amount of unfreezable water in the starches remarkably increased with time after the high pressure treatment or the heat treatment, as compared with normal starches.
From the above-mentioned results, we consider that the starches gelatinized by heat treatment or denatured by high pressure treatment are different with respect to the mechanisms of water penetration into starches as well as the distribution of the molecular networks formed by gelatinized starches.

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This study describes the fabrication of humidity sensor of anodized aluminum oxide film for the evolved gas analysis method. Water vapor is rapidly adsorbed on and desorbed from aluminum oxide layer formed by electrolytic anodization. The sensor used in this study detected the relative humidity change quickly. In the low humidity region (0 to 20%RH), it was found that the output of sensor increased linearly with increase in the amount of humidity in atmosphere. This sensor can be applied for analyses and measurments of the decomposition reactions involving water vapor evolution, and also of the reduction reactions of several oxides with hydrogen.

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The thermal unfolding of glutathione synthetase was studied in three different buffers at pH 7.5 by differential scanning calorimetry. Variation of protein concentration caused the change in the peak temperature of DSC curves observed. It was found that the calorimetric enthalpy becomes larger as the buffer ionization heat becomes larger. The results were discussed in the terms of a possible involvement of the process characterized by a dissociation of the terameric enzyme into monomeric unit during the unfolding.

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The order-discorder transition of binary interstitial alloys has been reviewed for the IVA transition metals (titaniuim, zirconium and hafniuim)-oxygen solid solutions. The order-disorder transition models for binary interstitial alloys are lacking, compared to binary substitutional alloys as described in the previous paper. The experimental entropy changes due to the order-disorder transition for binary interstitial alloy are compared to the theoretical values calculated by using statistical thermodynamics. In this paper, heat capacity anomaly in non-equilibrium state observed below the order-disorder transition temperature has been also reviewed.

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Thermodynamic nature of bilayer assembly of phospholipids in aqueous medium have been reviewed mainly from the view point of surface properties of lipid dispersions. In particular, emphasized was usefulness of the equilibrium spreading pressure (Π_e) measurement at the air-water interface related to the phase studies of lipid bilayers. The phospholipids studied were dimyristoylphosphatidylcholine (DMPC), dipalmitoylphosphatidylcholine (DPPC), and dimyristoylphosphatidylglycerol (DMPG). Also described briefly were the precise heat capacity measurements of DMPG dispersion in aqueous NaCl in the temperature range above main transition, the formation of complex between phospholipids and cholesterol, and the solubilization of apolar compounds in DMPC bilayer.

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Calorimetric data on heats of fusion of rocks have been very limited. In our investigation, high-temperature drop calorimetry was performed to measure heats of fusion of mantle rocks in the system CaO-MgO-Al₂O₃-SiO₂. Heats of fusion of natural mantle rocks under high pressure were estimated by correcting effects of FeO and Na₂O components, pressure and temperature on melting enthalpies to the observed heats of fusion. It is suggested that mixing enthalpy of silicate melt in the system CaO-MgO-Al₂O₃-SiO₂ is nearly zero by comparing the heats of fusion determined calorimetrically with those calculated by summing melting enthalpies of CaAl₂Si₂O₈, CaMgSi₂O₆, MgSiO₃ and Mg₂SiO₄.

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