dissolved nitrate and nitrite 基本例句 硝态氮 Some commercial laboratories use periodic nitrate tests as guides.许多商业性的试验室已应用定期的硝态氮分析作为指导。 The nitrate vertical transport rule in farmland soil of Tai Lake area was studied.摘要用模拟土柱和田间定期采样的方法对太湖地区农田土壤中硝态氮垂直运移规律进行了研究。