The growth thermograms observed with a multiplex isothermal calorimeter during growth at 30°C were employed for the determination of various parameters characterizing the growth and heat production of a Saccharomyces cerevisiae strain. The heat evolution curve, cell number curve and ethanol production curve determined for the yeast culture were found to be correlated, and the values of the growth rate constant μ determined from these curves were, respectively, 0.37, 0.34 and 0.32h^-1. From the correlation existing between the heat evolution curve and the cell number curve, an average heat evolution Q=(1.35±0.02)×10^-7 J cell^-1 and a corresponding q₁=20±3pW cell^-1 for the average heat evolution rate for a single cell were determined. Similar considerations allowed the determination of the average heat amount (Q_E=147.6kJ mol^-1) and the average number of yeast cells (N_E=1.09×10¹² cell mol^-1) associated with the production of one mole of ethanol. On the second hand, a new method was proposed for the determination of the average heat evolution rate per cell, which requires only the knowledge of the initial number of cells (the inoculum size) and the selection of an arbitrary level α on the time derivative of the heat evolution curve observed for the yeast culture. The values of q₁ determined using this method were found to depend on the level α, but the average was q₁=28.0±2.4pW cell^-1, which is relatively close to the value determined by the classic method.

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In this study, we investigated thermal properties of native ovalbumin (OVA) solutions as well as gels prepared by high temperature heat treatment using differential scanning calorimetry (DSC). The denaturation temperature, t_d, and the heat of denaturation, ΔH, of native OVA in water were found to take a constant value of 75.0°C and 890kJ mol^-1 for OVA concentration C ranging from 5 to 58 wt%, respectively, whereas rising of t_d and a decrease in ΔH occurred with a further increase in C. Assumption of the closest packing for OVA with bound water at C=58wt% gives that the amount of bound water on the OVA surface is 0.36g per g of OVA with C < 58wt% and decreases with increasing C. The thickness of the surface layer is then estimated as 0.36nm for OVA sphere with the diameter of 5.6nm. Aqueous OVA solutions with C≥10wt% showed three exothermic peaks at around 140°C, 170°C and 220°C, which may be related to transformation from the randomly aggregated state of OVA to stable gel network, to breakage of the S-S bond and to degradation of the protein itself, respectively. Circular dichroism measurement revealed that a decrease in α-helix content at around 80°C was followed by decreases in the β-sheet and the β-turn contents at higher temperature, which indicate that changes in the secondary structure of OVA play a deterministic role for gel formation in the temperature range of 100-140°C and for subsequent transformation to the random coil form before degradation starts at 200°C. Two organic solvents, glycerin and ethylene glycol, and their water mixtures were used as solvent to study the effect of hydrophobicity on thermal behaviour of OVA. Quite complicated changes in t_d and ΔH with mixing ratio were observed, and ethylene glycol was found to interact more strongly with native OVA than glycerin did.

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High temperature heat capacity of fluorite compounds has been reviewed. The lambda-type peak originating from the order-disorder transition of an anion sublattice has been found in many fluorite compounds at high temperatures. By doping, two different changes of the transition temperature and/or the peak shape of the heat capacity were observed in the phase transition of fluorite halides. The onset temperature of UO₂, at which heat capacity started to increase rapidly, was observed to increase with dopant content.

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8 years has passed since the announcement of cold fusion in 1989. During this period many works have been done and many reports have been published including both negative and positive results. In this paper these results were summarized mainly from the heat measurement or the calorimetry. Although many results showed that something happened especially for excess heat, the results can not be connected to fusion reactions. Further study is necessary for this phenomena.

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