利用X射线衍射仪鉴定肥料尿素真伪的方法研究  

X-ray diffractometer used to non-destructively identifying urea fertilizer product

作　　者：王林洋 唐杉 张育维[1] 温云杰 汪洪 WANG Lin-yang;TANG Shan;ZHANG Yu-wei;WEN Yun-jie;WANG Hong(Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences/National Center for Quality Supervision and Test of Chemical Fertilizers(Beijing)/Laboratory of Quality and Safety Risk Assessment for Agricultural Products from Fertilizer Sources,Ministry of Agriculture and Rural Affairs,Beijing 100081;The Soil and Fertilizer Institute,Anhui Academy of Agricultural Sciences,Hefei Anhui 230031)

机构地区：[1]中国农业科学院农业资源与农业区划研究所,国家化肥质量检验检测中心(北京),农业农村部农产品质量安全肥料源性因子风险评估实验室(北京),北京100081 [2]安徽省农业科学院土壤肥料研究所,安徽合肥230031

出　　处：《中国土壤与肥料》2023年第9期234-240,共7页Soil and Fertilizer Sciences in China

基　　金：国家重点研发计划项目(2022YFD1700603);农业农村部测土配方施肥项目(2019-2023年);国家农产品质量安全风险评估项目(GJFP2019035和GJFP2019037);中央级公益性科研院所基本科研业务费专项(Y2019PT20-04和1610132019018)。

摘　　要：市场上常有尿素假冒伪劣产品出现,给农民和农业生产带来极大危害。根据国家推荐性标准GB/T 2440—2017《尿素》对样品进行技术指标检测,该鉴别方法准确可靠,但检测周期长、成本高、费时费力。为建立一种利用X射线衍射仪(X-ray diffractometer,XRD)鉴别肥料尿素真伪的方法,选择17个不同厂家生产的尿素产品及尿素试剂,利用XRD进行测定,获得样品衍射峰晶面间距d值、峰位2θ角值、衍射相对强度I/I0等特征值,通过平均数计算,建立了尿素XRD特征指纹图谱,得到共有特征峰11个:2θ角值分别为22.25°、24.59°、29.29°、31.64°、35.50°、37.07°、40.48°、41.54°、45.39°、49.53°、54.91°。2θ角值为22.25°时峰强度最大,相对衍射强度定为100%,以此为基准,相对衍射强度为2%~10%和0.5%~2%所对应的特征峰分别各有5个。选择11个不同肥料样品,通过XRD测定,利用相关系数法、夹角余弦法进行相似度匹配,开展XRD鉴定方法的验证研究。结果表明,尿素正品衍射峰晶面间距d值或峰位2θ角值与特征指纹图谱的相关系数及夹角余弦分析结果绝对值较高;伪品和混有尿素的样品的相关系数及夹角余弦分析结果绝对值较低,相似度匹配不高。掺混有部分尿素的样品,虽然也可检测出部分特征峰,但仍可通过相似度匹配开展有效鉴定。本研究建立利用XRD技术有效鉴别肥料尿素真伪的方法,该方法为无损检测,快速、准确、操作简单,可为识别尿素产品质量及其产品监管提供重要的技术支撑。The fake urea products in the market cause great harm to farmers and agricultural production.According to the nationally recommended standard GB/T 2440—2017 Urea,the conventional method for identifying the authenticity of urea products depends on analyzing nutrient contents.It is accurate and reliable,but it takes long time and high cost.The purpose of this study is to establish a non-destructive method for identifying urea fertilizer using X-ray diffractometer(XRD).Seventeen true urea products were selected to be measured by XRD.XRD fingerprint was presented with the parameters including interplanar crystal spacing d value,2θangle value,and relative diffraction intensity I/I0.XRD fingerprint of urea was characterized by eleven peaks as 2θangle values of 22.25°,24.59°,29.29°,31.64°,35.50°,37.07°,40.48°,41.54°,45.39°,49.53°and 54.91°.The peak with 2θ=22.25°showed the highest diffraction intensity,which was defined as 100%of relative intensity.There were 5 peaks with relative diffraction intensity from 2%to 10%.The other 5 peaks had the relative diffraction intensity with a range of 0.5%~2%.To verify this method,the similarity analysis of eleven fertilizer samples for matching urea fingerprint were carried out by correlation coefficient and angle cosine method.The samples were identified as true urea when the absolute values of correlation coefficient and cosine angle were high.While the absolute values of correlation coefficient and cosine angle were lower in the fake urea samples or mixed urea samples which had lower similarities as well.Although some of the characteristic urea peaks could also be detected in the mixed urea samples,these could still be identified by similarity matching.XRD technology could effectively be used for non-destructively identifying the urea fertilizer.It might provide important technical support for ensuring the quality of urea products and its product supervision.

关 键 词：肥料尿素 X射线衍射 指纹图谱 相似度评价 

分 类 号：S143[农业科学—肥料学]