Abstract
The experimental results obtained as follows : (1) In cyanamide solution at pH 8.9 most of cyanamide molecules polymerise to dicyandiamide, but the formation of dicyandiamide is decreased by a addition of Acid earth (Japanease acid clay) or Komaba soil to this solution, and in these solutions Acid earth and Komaba soil adsorb cyanamide and morover Komaba soil hydrolyze cyanamide to urea. From these facts, it is concluded that the adsorption and hydrolysis of cyanamide molecules by Acid earth or Komaba soil disturb the formation of dicyandiamide from cyanamide. (2) In a soil the formation of dicyandiamide from calcium cyanamide is not only affected by a pH value of a soil, but also greatly by the certain colloidal substances which have the catalytic actions of hydrolysis of cyanamide molecules, and the more a soil contains these colloids. the less amount of dicyandiamide formes. (3) Dicyandiamide is more stable in neutral than in acid solution (pH 2.72), but on the contrary guanidinphosphate is relatively stable in acid. (4) Nitrogen and phosphorous of guanylureaphosphate and guanidinphosphate are both absorbed by Komaba soil, at which absorptions those two elements do not appear to be absorbed in these molecular conditions respectively, and nitrogen of the former compound is more easily absorbed than the latter, and dicyandiamide and guanidinhy-drochloride are only slightly. (5) The results of ammonification and nitrification of Lime Nitrogen, urea, dicyandiamide and guanylureaphosphate in paddy-field and field conditions are nearly agree with those of other many investigaters. In above both conditions of soil guanidinphosphate, guanidinnitrate and guanidincarbonate decompose very slow at lower temperature, but slightly rapid at higher temperature, and guanidion salts easier than dicyandiamide.
