The exothermic phenomena in the air oxidation of the mixture of sodium sulfide with carbonaceous materials were investigated by means of calorimetry.
Anhydrous sodium sulfide and three kinds of commercially available carbon blacks were used. The calorific values of the mixtures varied with the difference in the kind of carbon black used. Sodium sulfide in the mixture changed into sodium thiosulfate, sodium sulfite and sodium sulfate during the exothermic reaction.
Similar chemical changes on sodium sulfide were observed in aqueous sodium sulfide solution in which carbon black was dispersed.
From these results, it seems reasonable to assume that several kinds of functional groups, for example, carboxyl or phenol group on the surface of carbon black have great effects in the exothermic reaction.

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The equilibrium decomposition pressures of vanadium (IV) oxide sulfate (VOSO₄) and the related thermodynamic data of thermal decompositions have been determined by a transpiration method and an electrochemical method using a ZrO₂-CaO solid electrolyte.
The Gibbs energies for the reaction:
2VOSO₄=V₂O₅+SO₂+SO₃ (1)
can be expressed by
ΔG°=329.1+0.36T(kJ) (680-863K).
Also the Gibbs energies for the reaction:
VOSO₄=1/2V₂O₄+SO₃ (2)
can be expressed by
ΔG°=204.2-0.21T(kJ) (843-863K).
Further, based upon the equilibrium decomposition pressure data for the thermal decompositions as mentioned above, SO₂, SO₃ and O₂ partial pressure dependence on the decomposition reaction rate have been investigated by an isothermal weight-change determination method varing the atmosphere. The reaction (1) in 1atm N₂ and SO₂-SO₃-N₂ (490-520°C), and O₂-N₂ (450-500°C) atmospheres was explained by a contracting cube model kinetic equation and both SO₂-SO₃ and O₂ partial pressure dependence were clearly obtained. The reaction (2) in 1atm SO₂ atmosphere (570-591°C) was explained by Avrami-Erofeev kinetic equation. The activation energies were also discussed.

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The influence of metallic ions such as Cd²⁺, Cu²⁺ and Hg²⁺ on the poly (A)·poly (U) duplex formed by an equimolar mixture of poly (A) and poly (U) was studied by using a modified differential scanning calorimeter (DSC) with a help of the spectral measurements.
The transition temperature, T₁, of poly (A)·poly (U) duplex shows a definite value of about 315K which is nearly independent of r (the mole ratio of metallic ion to phosphate in polynucleotide).
While, the dependence of the heat of helix-coil transition, ΔH, on r was divided into two cases: in the first case, when r is less than 10^-2, ΔH for Cu²⁺ and Cd²⁺ systems increases with an increase of r, but ΔH for Hg²⁺ system is a definite value which is nearly independent of r. In the second case, when r is in excess of 10^-2, ΔH for all systems shows a drastic decrease as r increases.
From the results of spectral measurements obtained, poly (A)·poly (U) duplex seems to form a complex with Cu²⁺ or Hg²⁺ at room temperature when r is more than 10^-2 except for Cd²⁺ system, and random coil structure of poly (A) and poly (U) obtained in which are the helix-coil transition of poly (A)·poly (U) duplex interacts also with metallic ions, and its interaction is expected to be exothermic. While, the behavior for Cd²⁺ system is the same to that of Cu²⁺ or Hg²⁺ system. However, the effects of poly (A)·poly (U) duplex on Cd²⁺ may differ from those of Cu²⁺ or Hg²⁺ systems.

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The method for analyzing crystallization kinetics by DSC was discussed on the basis of nucleation and growth equations. It was found that crystallization mechanism, that is, whether bulk crystallization or surface crystallization occurs, is very important for obtaining the meaningful activation energy. This was ascertained by applying the analytical formulae to the crystallization of Li₂O·2SiO₂ glass of which kinetic data on crystallization were already well known. It was also found that the so-called Kissinger plot is valid only when crystallization starts at the surface and growth progresses towards the inside of the glass one-dimensionally. It was concluded that the crystallization mechanism should be known in order to obtain the meaningful activation energy.

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Dynamic mechanical properties of composites, glass reinforced aromatic polyamideimide and BT resin, were measured by means of flextural osillation with a du pont 980 Dynamic Mechanical Analyzer (DMA), and tensile osillations with a Rheovibron DDV-II-C were used for comparison.
Corresponding molecular relaxations were found for each osillation mode.
It was found that flextural osillation mode (DMA) is particularly sensitive for a part of composites with low rigidity, while tensile osillation mode is susceptive for a part of composites with high rigidity.
DMA is especially well suited for study of dynamic mechanical properties of polymer composites.

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