Fertilizers — Determination of ammoniacal nitrogen content in the presence of other substances which release ammonia when treated with sodium hydroxide — Titrimetric method
肥料和灰分;在使用氢氧化钠处理时释放氨的其他物质存在的情况下测定氨氮含量——滴定法
The method consists in entraining, by means of a strong current of air, of the ammonia from a moderately alkaline test mixture at ambient temperature into standard volumetric sulfuric acid solution, and back-titrating of the excess sulfuric acid solution with standard volumetric sodium hydroxide solution.