长江三角洲沉积物标准物质研制

美国、加拿大等国家先后研制了10余个海湾和河口沉积物标准物质,但定值成分较少,大多侧重于有机污染物和放射性核素值。我国于2007年研制了3个黄河三角洲沉积物标准物质,为进一步满足近海地球化学调查及资源勘探的需要,本文按照ISO导则35和国家一级标准物质技术规范,研制了2个长江三角洲沉积物标准物质。按照不同粒径采集两个候选物样品,样品经干燥、球磨至200目,采用电感耦合等离子体质谱和发射光谱法进行均匀性检验,结果表明F实测值小于列表临界值F0.05(24,25)=1.96,样品均匀性良好。在两年时间内采用X射线荧光光谱法进行了4次稳定性检验,未发现统计学意义上的明显变化,样品稳定性良好。由12家有技术权威的实验室共采用13种准确、可靠的分析方法进行协作定值,最终定值元素53项,涵盖了主量、微量及全部稀土元素,其中主量成分含量呈梯度分布,如Al2O3的含量分别为16.42%、11.48%。该系列标准物质定值元素种类多,定值方法准确,能够为河口三角洲地区地质及环境调查的分析测试工作提供可靠的质量保证。

Preparation of Yangtze River Delta Sediment Reference Materials

More than 10 harbour and estuarine sediment reference materials have been developed in United States, Canada and other countries, but most of them focus on organic pollutants and radionuclide and lack certified values. Three sediment reference materials of the Yellow river delta have been prepared in China in 2007. In order to meet the needs of offshore marine sediments geochemical survey and resource exploration, two sediment standard materials of the Yangtze river delta were prepared according to ISO guidelines and technical standards for reference standards at the national level. Two samples were collected according to the different particle sizes, and were dried and ball milled to 200 mesh. Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) were used to test the homogeneity. Results show that the F values for the variance test were less than the threshold, which indicates good homogeneity. X-ray Fluorescence Spectroscopy was used for four-time stability test in two years. No statistically significant changes were observed and the stability of the samples was good. A total of 13 accurate and reliable analytical methods were used in 12 technologically significant laboratories to finalize the contents of 53 elements. The major elements show gradient distribution with 16.42% and 11.48% of Al₂O₃. These two reference materials have multiple elements with determined values by accurate and reliable methods, which can provide quality assurance for the analysis and testing during geological and environmental survey in the Delta region.