【作者】 苏苓；

【导师】 陶冠红；

【作者基本信息】 苏州大学 ， 应用化学， 2003， 硕士

【摘要】 为了克服温度及加热、冷却时间等因素对测定锰的影响，提出室温下测定痕量锰的新方法，即氨三乙酸（NTA）存在下，在pH5.4的HAc—NaAc缓冲溶液中，锰（Ⅱ）对高碘酸钠氧化季胺[4，4’—对（二甲氨基）—二苯基甲烷]反应有显著的催化作用，并利用流动注射技术分析速度快的特点测定了在602nm处有最大吸收的蓝色不稳定产物。在60样h分析速度下检出限为7.3×10^-11g／mL，线性范围为锰（Ⅱ）0～20μg／L，对10μg／L锰标准溶液测定11次的相对标准偏差为0.5％。应用于天然水样测定，结果令人满意。 本文包括以下主要内容： 第一章是绪论部分。简述了流动注射分析技术的基本理论，阐明了实验的催化动力学基本原理和体系的主要特点，并对催化动力学光度法测定锰的体系和应用进行了综述。 第二章是试验部分。主要介绍实验仪器、实验试剂和实验方法。 第三章是结果与讨论部分。首先论述了体系用于流动注射分析的可能性，然后介绍流动注射分析流路设计及试验参数的优化，探讨了反应的机理，最后检验了共存组分对测定的影响并进行了实际样品的测定。为验证方法的准确性和可靠性，对加拿大国家测量标准所的水质标样SLEW-2按本方法进行了测定。 第四章是结论部分。更多还原

【Abstract】 Trace levels of Mn is determined using flow-injection catalytic kinetic spectrophotometry. Due to the catalytic effects of Mn(II), strongly enhanced by nitrilotriacetic acid, sodium periodate could oxidize tetrabase [4,4’-bis(dimethylamino)-diphenylmethane] rapidly at room temperature in an acetate buffer medium (pH=5.4). Flow injection technique is used to control the merging and reaction timing of the reagents and samples. The measurements are conducted at 602 nm the unstable blue intermediate product of the reaction, which greatly improves the sample throughput. A detection limit (3 o ) of 0.073 ug/L is achieved at a sampling frequency of 60/h.The relative standard deviation is 0.5% for the determination of 10 ug/L Mn (n=l 1).The thesis is divided into four chapters.In the first chapter, a review is provided on the basic theories and advantages of flow injection analysis technique, and the basic principles of catalytic kinetic spectrophotometry and its main characteristics with the emphasis on the applications of manganese analysis by catalytic kinetic spectrophotometry.Chapter 2 introduces the apparatus, the reagents and the methods used in the present study.In the Results and Discussion, practical considerations on flow injection systems for the catalytic kinetic analysis of trace amounts of manganese are discussed, leading to the optimized flow injection manifold used in the present study. The possible mechanism of the kinetic reaction is given and discussed. The physical and chemical parameters are optimized and the potential effects of interferences on determination of manganese are examined. The optimized system is validated by the analysis of an estuarine water reference material, SLEW-2 (National Research Council of Canada) and applied to the analyses of several natural waters with satisfactory recoveries.Chapter 4 summarizes the characteristics of the proposed system.更多还原