定氯化钾溶液提取分光光度法.PDF

中华人民共和国国家环境保护标准 HJ 634—2012 土壤 氨氮、亚硝酸盐氮、硝酸盐氮的测 定 氯化钾溶液提取-分光光度法 Soil-Determination of ammonium,nitrite and nitrate by extraction with potassium chloride solution -spectrophotometric methods （发布稿） 本电子版为发布稿。请以中国环境科学出版社出版的正式标准文本为准。 2012-02-29 发布 2012-06-01 实施 环 境 保 护 部 发布 目 次 前 言 ······························································································································ ············· II 1 适用范围 ······························································································································ · 1 2 规范性引用文件 ··················································································································· 1 3 方法原理 ······························································································································ · 1 4 试剂和材料 ··························································································································· 1 5 仪器和设备 ··························································································································· 4 6 样品 ······························································································································ ········· 5 7 分析步骤 ······························································································································ · 5 8 结果计算与表示 ··················································································································· 7 9 精密度和准确度 ··················································································································· 8 10 质量保证和质量控制 ·············