[Measurement of uranium isotope ratio in solid sample by laser ablation and double-beam diode laser atomic absorption].
The 235U/238U isotope ratio was determined by diode laser atomic absorption spectrometry in a plasma induced by a Nd:YAG laser. Two diode lasers, which probed almost the same plasma volume, were used as light sources. 235U and 238U absorption signals were simultaneously measured by tuning the diode lasers to the absorption lines 682.6736 nm and 682.0768 nm, respectively. The optimal focus position for the Nd:YAG laser was found to be 0.4 cm below the sample surface. The precision and accuracy of 235U/238U isotope ratio determination were obtained to be 5% and 2%, respectively. The detection limit of the 235U isotope, evaluated on the basis of 3sigma criteria, was estimated to be 18 microg x g(-1). All these results show an improvement compared with the method in which only one diode laser was used as a light source.
Liu
Hong-tao
HT
Chemistry and Chemical Engineering College, Zhongshan University, Guangzhou 510275, China.
Zhang
Zhan-xia
ZX
Quentmeier
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A
Niemax
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