中国海大陆架沉积物超细标准物质系列研制

5个中国海大陆架沉积物标准物质的原样分别取自东海和南海,样品风干后,先经球磨制备成200目的均匀粉体,再用气流磨进一步加工成超细粒度的均匀样品.采用激光粒度仪检测了样品的粒度分布,5个样品的平均粒度均小于4 μm(约800目).采用高精度的XRF检验了样品的均匀性并以高灵敏度的ICP-AES、ICP-MS相配合确定了其最小取样量(5 mg).有12个实验室参加了合作定值研究,定值组分均为60个,其中MSCS-1,2分别有50和51个组分定为标准值,MSCS-3,4,5有52个组分定为标准值.全组分百分总和分别为99.9%, 99.9%, 100.4%, 100.1%和99.7%.

Preparation of Five China Sea and Continental Shelf Sediment Reference Materials with Ultra Fine Particle Size

The preparation and certification of five China Sea and continental shelf sediment reference materials MSCS-1- 5 are reported. The raw samples were collected separately from the East China Sea and the South China Sea. First,they were ground by a ball mill to a homogenous powder of less than 74μm,then these samples was further processed by an ultra-fine processing technique,a jet mill,to form an ultra-fine powder. The particle size distribution of the samples was determined with a laser particle-analyser,their average particle size is < 4μm. The homogeneity was tested by high-precision WD-XRF and the minimum sampling mass is 5 mg,which was confirmed by XRF,ICP-AES and ICP-MS. Twelve laboratories participated in the cooperative study and 60 constituents were determined. 50 and 51 components were certified as certified values and 1 and 2 components as reference values respectively for MSCS-1 and MSCS-2,52 constituents were certified as certified values for MSCS-3,4 and 5. The sum of the major and minor components in the five reference materials MSCS-1 -5 is 99.9% ,99.6% ,100.4% ,100.1% and 99.7% ,respectively.