| Abstract
| - Time-resolved laser-induced fluorescence (TRLIF) hasbeen used for direct uranium(VI) determination in thenuclear reprocessing medium. To take into account thedifferent phenomena that affect the uranyl fluorescence(absorption, quenching, and complexation), a model hasbeen defined. A spectral deconvolution procedureallowsuranium speciation in nitric acid and therefore nitratedetermination with good accuracy. After normalizationofthe fluorescence intensity, it is then possible to reachtheuranium concentration. Results obtained on syntheticsolutions and, above all, on reprocessing samples by theapplication of this model are presented and comparedwith results from other techniques. The limit ofdetectionfor uranium analysis in reprocessing matrices is in thesubmilligram per liter range, and a ratio of Pu/U as highas 105 can be directly analyzed.
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