摘要
铌、钽、锆、铪、稀土等伴生放射性矿样品较难用常规的混酸分解,采用过氧化钠在700℃下熔融,热水提取,硝酸酸化,用紫外脉冲荧光法进行铀的测定,方法简单,抗基体干扰能力强。测定范围为0.66μg·g~(-1)~4 500μg·g~(-1),在铀含量为3 000μg·g~(-1)时,方法的精密度2.55%,在300μg·g~(-1)左右时,方法的正确度5.21%。
NORM samples with Nb, Ta, Zr, Hf and Rare Earth Elements are difficult to be decomposed by mixed acid. In this paper, NORM samples were fused with Na_2O_2 at 700 ℃, extracted by hot water, acidized with nitric acid, and the uranium content was measured by Ultraviolet Pulse Fluorometry. The method is simple, and has strong anti-matrix interference ability. The measuring range of U is 0.66 μg·g~(-1)~4 500 μg·g~(-1), precision with relative standard deviation is 2.55% when the content of U is 3 000 μg·g~(-1), trueness with relative bias is 5.21% when the U content is 300 μg·g~(-1).
引文
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