Abstract
Commercial DAHG J. P. was kept in various concentrations of aqueous ammonia and the following results were obtained. 1. When the sample was aged in aqueous ammonia, a temporary acceleration of the neutralizing rate was observed at an early stage of the aging process, as was similar to the results obtained in the previous paper. 2. The process of aging was composed of two steps : an increase of the diffraction around 36∼42°of 2θ value and an appearance and development of the peak at 18∼20°of 2θ. The former is considered to be related with the temporary acceleration of the neutralizing rate. 3. Depending on the concentration of aqueous ammonia, the aging product was different, and especially in the case of 28% aqueous ammonia, it resembled to nordstrandite. 4. The growth rate of crystal on the aging, in the case of 28% aqueous ammonia, was explained by the existing experimental equation, i. e., by equation(1). 5. The infrared absorption around 3400 cm-1 was sharp compared with that of the aged sample in various atmosphere under relative humidity in the previous paper, and it was recognized to be shifted remarkably to 3700 cm-1.
