Two approaches for the analysis of DSC and DTA curves have been examined experimentally using pure indium and anthracene as well as by electric and infrared pulse heating of the sample container. Melting curves of triangular shape were obtained. The approach based on the theory of heat transfer was found to be valid in the melting of pure substances. On the other hand, the other approach based on the linear theory of control and measurement was found to be valid in the electric heating and the infrared irradiation experiments by examining linearity and superposition. The differing results depending on conditions are explained by the fundamental equation of heat transfer and apparatus design.

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The heat capacity of vacuum greases has been measured by laser-flash calorimetry at a temperature region from 80 to 400K. Both Apiezon-N and -T showed an anomaly in heat capacity from 220 to 320K, while silicone grease showed a sharp anomaly around 230K. The best choice of a vacuum grease is discussed for the use in maintaining thermal contact between sample and light-absorbing disk in laser-flash calorimetry.

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A direct-current power amplifier has been constructed for use in a temperature controller, in which a light-coupled transistor (electro-optical coupler) incorporated in the amplifier circuit separates the potentiometric null detector from the heater circuit with respect to the electrical potential relative to the ground. This feature gives a wider choice of the grounding points and larger tolerance about the electrical insulation between the thermocouple and heater in the thermostat than is possible with a direct-coupled amplifier. By using a copper-constantan thermocouple as the thermometer, temperature stabilization within 3mK was readily attained at 220K. Application of the apparatus in the adiabatic calorimetry is suggested.

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In the previous papers, we measured the heat of dilution of the atactic polystyrene solution and found that the interaction heat parameter between the polymer and the solvent depended on the concentration and molecular weight of the polymer.
In this paper, we measured the heats of dilution of the isotactic polystyrene-toluene and -anisole systems in order to see the effect of tacticity on the solution property. The results indicate that the isotactic-anisole system behaves similarly, but the isotactic-toluene system dissimilarly to the atactic polystyrene solutions.

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The thermodynamic relations of chemical equilibrium of the multi-steps reactions in aqueous solutions are roughly summarized for calorimetric measurements of the reactions of metal-ligand complex formation.
Two types of the computational analysis of enthalpy measurements are introduced, the one calculates the enthalpies by using the known equilibrium constants come from the other measurements and the other simultaneously obtains the enthalpies and the equilibrium constants. A few types of calorimeters which have ever used are introduced and the titration calorimeter is favourable because of the needs of many successive data for the enthalpy measurements of the reactions of metal-ligand complex formation.

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