A calorimetric analysis was made to characterize quantitatively the action of ethanol on the growth activity of yeast cells at 30°C. By using the multiplex calorimeter previously desinged, the growth thermograms of the yeast grown in liquid media containing ethanol at different concentrations were observed and the inhibitory effect of ethanol on the growth was analyzed in terms of the effect on specific growth activities as evaluated from (1) the change in growth rate constant and (2) the extent in retardation of growth. The ethanol concentration at which the specific growth activity is repressed by 50%, K_i, the index term to express the cooperativity of ethanol action, m, and the minimum inhibition concentration, MIC, determined from the two different view points were found to be in good agreement. From the result obtained it was concluded that the theoretical background employed for the analysis is a reasonable one and that the method of analysis developed here is useful for the quantitative study of the interactions between drugs and microbial cells.

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Excess enthalpies of eight binary mixtures between each of methyl methylthiomethyl sulfoxide (MMTSO) and dimethyl sulfoxide (DMSO) and one of cycloethers (oxepane, oxetane, 3, 4-dihydroxy-2H-pyrane and furan) have been determined at 298.15K. All those mixtures show positive excess enthalpies over the whole range of mole fractions except furan+MMTSO, furan+DMSO, and oxetane+MMTSO. Excess enthalpies of the cycloether+MMTSO or+DMSO decrease with increasing the number of oxygen atoms in the cycloether molecules, except oxolane+MMTSO and increased with increasing methylene radicals in the ring. Excess enthalpies of MMTSO+cycloethers are smaller than those of DMSO+cycloethers for the same cycloether except the 1, 3-dioxolane mixtures. The excess partial molar enthalpies at infinite dilution of mixtures of cycloethers+MMTSO and+DMSO were affected strongly by dipole-induced dipole interactions.

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Recent calorimetric studies on the structural fluctuations and irreversible relaxation processes in supercooled liquids are summarized centering around our works. The temperature jump method in the time domain under constant temperature condition is stressed to be powerful in characterizing the slow dynamics among various methods. The nonlinearity of the relaxation functions to the magnitude of temperature jump has been proved by the method to originate from the non-Arrhenius property of the relaxation times under equilibrium.

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Recent topics on the thermodynamic database have been reviewed with an emphasis on the thermodynamic database MALT2 and related activities. The fundamental idea of constructing the thermodynamic database MALT2 was described together with recent achievements on methods of constructing generalized chemical potential diagrams and of calculating chemical equilibria and their utilization in the materials sciences. Particularly, usefulness of the correlation of the stabilization energy of double oxides with the ionic properties was stressed. Some problems encountered during the utilization of database with advanced software were described. Future prospect on the thermodynamic database of compounds was discussed in comparison with the phase diagram calculations treating the solution properties.

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Several methods such as the direct heating pulse (intermittent) method, the high-temperature differential-scanning method with triple cells, the laser autoclave technique and the high-speed cooling method are described for the heat capacity measurement of both metallic and ceramic materials at high temperatures above 1300K. The principles, instrumentations, recent developments and some experimental results of the two new dynamic techniques at ultra high temperatures above 2000K i.e. the laser autoclave technique and the high-speed cooling method are mainly discussed in detail.

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