原文由 andy917(andy917) 发表:
我也被這樣的問題揪心著:測的7E都可以,就是鉻的檢測值在25ppm左右浮動,而且我連續做了三天,每天四平行!開始我懷疑是標樣材質不均勻,先用XRF掃後和標值差不多,接著我把它剪碎了後再均勻稱量,得到的ICP最後檢測結果依舊。還請路過的大俠指教一二!
Additional Material Information | |
Mass Fraction 1 [mg/kg] | |
Acid digestible Cr | 2.9 – 16.2 |
1) Range of results obtained by conventional acid digestion of the material in 9 laboratories. The value of the amount of acid digestible Cr depends on the sample intake as well as on digestion conditions (acid mix, temperature, pressure). |
原文由 damoguyan(damoguyan) 发表:原文由 andy917(andy917) 发表:
我也被這樣的問題揪心著:測的7E都可以,就是鉻的檢測值在25ppm左右浮動,而且我連續做了三天,每天四平行!開始我懷疑是標樣材質不均勻,先用XRF掃後和標值差不多,接著我把它剪碎了後再均勻稱量,得到的ICP最後檢測結果依舊。還請路過的大俠指教一二!
用微波多消解几遍,不要看消解清了(眼看澄清不算,继续消解几遍)
我用一个比较差的微波一次消解眼看是澄清的,但测试结果老是20-60ppmCR(很多次都这样)
后来消解2遍,得到CR108PPM,有时间大家也多消解几次试试。。。。
EC681K证书中有以下说明,CR的值在20-80之间也是正常的:
你这消解用什么试剂,什么升温程序,能将里面的CR做的这么好,108PPM?
Additional Material InformationMassFraction1
[mg/kg]
Acid digestible Cr2.9 – 16.2
1) Range of results obtained by conventional acid digestion of the material in 9 laboratories. The value of the amount
of acid digestible Cr depends on the sample intake as well as on digestion conditions (acid mix, temperature, pressure).
DESCRIPTIONOFTHESAMPLE
The sample consists of approximately 100 g granulate of low-density polyethylene (LDPE) spiked with various pigments to obtain the desired element contents.
Note: A significant fraction of Cr is in the form of Cr2O3. Not all digestion methods will therefore result in full digestion.