The molar enthalpies of transfer of methanol, 1-propanol, and 1-pentanol from aqueous to aqueous cycloheptaamylose solutions have been determined by direct calorimetric measurements at 298.15K as a function of the mole fraction of the alcohols. The experimental result of the enthalpy for methanol was athermal and those for 1-propanol and 1-pentanol were endothermic. The enthalpies of inclusion of the latter two alcohols by cycloheptaamylose in aqueous solutions have been evaluated by the method proposed earlier by the present authors [Nippon Kagaku Kaishi, 1983 (2), 188.].

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A gas adsorption calorimeter has been remodelled for use in studies of water vapor sorption on biological materials.
Major modifications on a sorption vessel and a water vapor delivery system were made on a commercially available calorimeter. The time constant of the calorimeter response is 2min and the heat effect sensitivity is about 0.12μV/μW.
Test experiments which include electrical calibration and measurements of water vapor sorption on potato starch indicate that the calorimeter is available for studies on the physical properties of water in biological materials.

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Oxygen pump using a calcia stabilized zirconia solid electrolyte with silver electrodes has been made to pump out the impurity oxygen in commercial nitrogen gas. The ability as oxygen pump has been investigated by changing the applied voltage. The oxygen in the gas has been pumped out down to 10^-13 atm at temperatures above 800°C when the applied voltage to the pump was fixed at 1.0V. From the experimental result, it is found that the oxygen pump in the present study is quite satisfactory for a long term use.

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Krafft point is well known as the temperature above which the solubility of a surfactant increases dramatically in aqueous systems. Two kinds of model have so far been proposed to explain this anomalous solution behavior of surfactant. Some new experimental evidences in support of the melting-point model for the Krafft point, one of the above two models, were given recently by the present author and his collaborators. The Krafft point vs. composition curves of the binary surfactant mixtures have been studied and found to be classified into three groups. In the case of group I, there exists a minimum in the Krafft point at a certain composition, whereas the Krafft point for the group II varies monotonously with the composition change. The every diagram of the group III, on the other hand, has a maximum Krafft point. These three types of phase diagrams correspond to the eutectic, solid-solution forming, and addition-compound forming systems observed in the melting point vs. composition curves of the binary mixtures of ordinary substances. A novel Krafft-point depression phenomenon of some zwitterionic surfactants caused by inorganic salts is also argued thermodynamically based on the melting-point model for the Krafft point.

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The thermal endurance occupies very important part in the physical and chemical properties of electrical insulator. Therefore, an estimating method of endurance has been standarized up to the present. This method takes long time over one year to get a measured data. It seems to be inconsistency that such a very slow measurement is called a rapid thermal endurance testing method. At present, the study is making an tremendous rapid progress even in Material Science, and present standardized measurement method cannot keep pace with exploitation of new material. So a new more rapid method which would finish one measurement within a short time, as several weeks, has been pursuing now throughout the world. Based upon such a trends, The Institute of Electrical Engineers of Japan has planned to have committee which determine a new rapid measurement method of thermal endurance of insulators, and carried out some joint experiments with several laboratories on the thermogravimetry. The committee was able to get the some results from the experiment for enamelled wire, and arrive at following conclusion that methods as a) and b) would be one of the most usable for rapid estimate of thermal endurance;
a) a method to use I, and TGI at specified temp.
b) a method to get the ΔE value from a few TG curve.

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