The pupa of silkworm was putrefied in a jar at room temperature for 57 days and the extract was subjected to the analyses, and found : 1.) a large quantity of propionic acid was produced ; 2.) all the amino acids and organic bases, with an exception of putresin, disappeared entirely ; 3.) 82% the total nitrogen present in the putrefied mass was found to be ammoniacal which suggests that the original nitrogenous substance in the pupa was in easily decomposable form.

抄録全体を表示

Various nitrogenous organic fertilizers was added to the soils from both the dry-farm and the paddy-field, and their effect on the form of iron was investigated. It was found that the amount of ferrous iron was increased in all the soils, particulary it is noteworthy that a marked increase of the ferrous iron which is soluble in dilute acid took place in the paddy-field soil.

抄録全体を表示

The possibility of using selenium in place of yellow mercuric oxide in the total nitrogen determination was investigated, taking rape cake, bone meal, hoof meal and calcium cyanide, and found that 0.2g. selenium is equally efficient as the catalyser as 0.7g. of the mercuric oxide ; the digestion was faciliated by the use of selenium together with potassium sulfate ; in case of selenium, no addition of precipitator is necessary in distillation ; if phosphate determination made in the digested solution, it can be carried out easily after precipitating the selenium by adding powdered zinc ; also economically, the use of selenium is advantageous.

抄録全体を表示