A dialytic battery was constructed; three compartments which were well agitated, were made with a cation exchange membrane and an anion, each having an area of 14 cm², and two Ag·AgCl for the positive electrode and the negative. Discharge characteristics of the battery in which the sodium chloride concentration in the electrode compartments and in the middle compartment were initially 3.5×10⁴mg/liter and 350mg/liter respectively, were in vestigated. The maximum external power obtained has been 22 mW/m². Better efficiency of energy conversion may be obtailled with exchange membranes having low electric resistance and transport number close to unit. The observed E. M. F. was about a half of the theoretical value of the concentration potential at higher concentration ratio 100:1. Decreasing the ratio, the discrepancy becomes less owing to the lessening of electric resistance in the middle compartment.

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A spectrophotometric method for the determination of boron using azomethine H was studied and applied to the analysis of sea water, brine and bittern samples. Boron reacts with azomethine H at pH 4.5-5.8 to form a colored complex having absption maximum at 412 nm, which canb e used for the determination of boron. Beer's law is obeyed up to the concentration of 30μg/25 ml of boron. The apparent molar absorptivity of the complex is 8,300lmol^-1cm^-1 at 412 nm. Some metal ions interfering determination of boron with azomethine H can be effectively masked by EDTA and can be tolerated without further separation. When known amounts of boron wasadded to the sea water samples, the boron was recovered satisfactorily.
Boron content in sea water samples was estimated to be 4.15-4.76mg/liter, and that in brine and bittern samples produced by the ion-exchange membrane method to be respectively 2.67-3.13mg/liter and 53.9-64.1mg/liter. Boron content in those samples produced by the salt-field method was much greater.

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Solubility of krypton in the 0-40 wt% sodium hydroxide aqueous solutions was measured at 10-40°C. And the thermodynamic values on dissolution of krypton were caluculated from the solubility data to serve to the discussion on structure of sodium hydroxide aqueous solution.
Correlation between structure and concentration of sodium hydroxide aqueous solution was investigated on the base of a two-step mechanism of the dissolution process. And it was shown that water structure might be maintained in the sodium hydroxide aqueous solution less than 28.9 wt% but a pseude-structure of NaOH·3.5H₂O crystal might be predominant in 39.9 wt% solution.

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In their previous papers (this Journal, 14, 227 (1960); 26, 205 (1972); 27, 321 (1974)) the authors reported the isotherms of the quinary system NaCl-KCl-MgCl₂-CaCl₂-H₂O at 25°C, 50°C and 75°C.
In this paper, equilibria of the ternary systems NaCl-CaCl₂-H₂O, KCl-CaCl₂-H₂O and the quatermary system NaCl-KCl-CaCl₂-H₂O at 110°C were studied.
This study was done to complete the equilibrium diagram of the five component system NaCl-KCl-MgCl₂-CaCl₂-H₂O at 110°C, which would be useful for the calculation of isothermal evaporation of natural gas brine, ion exchange membrane brine etc.
Based on the data obtained by using the DTA, X-ray analysis, atomic absorption spectroscopy and chemical analysis, isotherms and invariant points of the ternary systems NaCl-CaCl₂-H₂O, KCl-CaCl₂-H₂O and the quaternary system NaCl-KCl-CaCl₂-H₂O were determined.

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