果树中总氮测定的新方法——紫外分光光度法  

A New Method to Determine Total Nitrogen in Fruit Tree by Ultraviolet Spectrometry

作　　者：李秀珍[1] 李学强[1] 朱艾红 

机构地区：[1]河南科技大学,河南洛阳471003 [2]孟津县小浪底镇林科所,河南孟津471100

出　　处：《河南农业大学学报》2006年第3期242-245,共4页Journal of Henan Agricultural University

基　　金：河南省科技攻关项目(0324070091)

摘　　要：以日光温室及露地栽培的甜樱桃植株为试材，通过对干燥方法、微波消解条件、微波消解剂、碱性过硫酸钾浓度、碱性过硫酸钾消解条件等的研究，建立了果树中总氮的分析方法——微波消解．过硫酸钾氧化-紫外可见分光光度法，即样品先经冷冻干燥后磨细，用H2SO4＋H2O2微波消解，再利用碱性过硫酸钾V（NaOH）：V（K2S2O8）=0．15：0．15在123～125℃下保温60min使消解液中的氨和亚硝酸氧化为硝酸盐，最后用紫外可见分光光度法测定样品中的总氮．植物标样GBW07603的平行测定分析表明该方法具有简便、快速、灵敏、准确等特点，适合于植物样品中总氮的测定．A method of microwave digestion-potassium persulfate oxidation-ultraviolet spectrometry was proposed in this paper for the determination of total nitrogen in fruit trees. The samples were dried by lyophilization, then grinded to 80 mesh, and then digested using H2SO4 ＋ H2O2 by microwave digestion. Alkaline K2S2O8 were used to oxidize NH4^＋ and NO2 in digestion solution to NO3 and the optimal conditions were established, under which samples were heated to 120 ℃ for 60 min. Total nitrogen in sample was determined by ultraviolet spectrometry at last. The accuracy of the method was confirmed by determining standard plant sample of GBW 07603. This method was proved to be simple, rapid and repeatable and accurate, and it is suitable for the determination of total nitrogen.

关 键 词：果树 总氮 微波消解 过硫酸钾氧化 

分 类 号：S662.5[农业科学—果树学]