3、Fertilizers--Determination of ammoniacal nitrogen content--Titrimetric method after distillation
4、A yellow colour indicates the presence of ammoniacal nitrogen. Measure the transmittance of the solution by a spectrophotometer and compare the result with the standard curve.
2、Fertilizers--Determination of ammoniacal nitrogen content--Formaldehyde method
1、ammoniacal nitrogen [water quality objective]