摘要
非完全消化处理样品，即在低温下用高氯酸-硝酸混合酸(1+4)消解样品，再用乳化剂 OP溶解消解过程中产生的油脂而配制成均匀、透明的样品溶液。样品处理条件为：酸溶剂种类为硝酸-高氯酸混合酸，酸溶剂用量是5ml、最佳消解温度是60℃，最佳消解时间为30min。
建立了非完全消化-火焰原子吸收光谱法快速测定水果中的铁、锌的分析方法，用标准曲线法测定。实验的仪器条件选择如下：测定样品中铁元素含量时，最佳波长为236.1nm，最佳灯电流为2mA，最佳燃气流量为1L/min。测定样品中锌元素含量时，最佳波长为201.8nm，最佳灯电流为8mA，最佳燃气流量为1.5L/min。对非完全消化法样品处理条件、混合酸及介质的影响、样品处理条件、背景吸收干扰及检出限进行了考察。测定结果的相对标准偏差小于2％。样品的回收率为99.5-106.8%.非完全消化法处理样品较完全消化、干灰化更简便、快速、准确。
100g新鲜水果样品中铁元素含量范围为18.68-65.25μg/g。六种水果含量由大到小依次为：杏﹥油桃﹥芒果﹥草莓﹥香蕉﹥梨；锌元素含量范围是51.63-166.87μg/g。含量由大到小依次为：草莓﹥杏﹥芒果﹥油桃﹥梨﹥香蕉。
关键词：火焰原子吸收光谱法；水果；铁；锌
Abstract
The sample was treated by noncomplete digestion method, which is digested in mixed acid of HClO4-HNO3 (1+4) under low temperature. The fat produced during the digestion process was dissolved by adding emulsifier OP and given a homogeneous and transparant solution of sample. The sample processing condition: the kind of acid solvent is nitric acid - perchloric acid, the used amount of acid solvent is 5ml, the optimal digestion temperature is 60℃ and the optimal digestion time is 30min.
A noncomplete digestion-flame atomic absorption spectromery for rapid determination of iron and zinc in fruits have been developed and the level curve method was used to determine. When determining the content of iron in sample, the optimal wave length, the optimal lamp electric current and the optimal gas flow is 236.1nm, 2mA, 1L/min, respectively. And when determining the content of zinc in sample, the optimal wave length, the optimal lamp electric无忧论文 【http://www.uklunwen.com】 current and the optimal gas flow is 201.8nm, 8mA, 1.5L/min, respectively. The pretreatment conditions of sample in noncomplete digestion method, effects of mixed acid of HClO4- HNO3(1+4)and medium, the pretreatment condition of sample, background absorption interference and detection limit were studied.The relative standard deviations were less than 3.8％.The recoveries were from 99.5% to 106.8%. The sample that was treated by nonconplete digestion method was more convenient and accurater than treated by digestion method and dry ashing.
In these six samples, the iron seauence of these fruits is from 16.68 to 65.25μg/g on the 100g crisp samples. In these six fruits, the iron content is subdivided in descending order: apricot> peach> mango> strawberry> banana> pear. And the zinc seauence is from 51.63 to 166.87μg/g. The zinc content is subdivided in descending order: strawberry> apricot> mango> peach> pear> banana.
Key words：flam e atomic absorption spectrometry; fruit; iron; zinc
|
|
论文题目：
（环境）香蕉等水果中铁、锌元素含量的测定 
