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Les techniques de spectroscopie laser sont de plus en plus employees pour l'analyse elementaire a bas niveau et la speciation des actinides et autres radionucleides d'interet. A partir d'une recherche bibliographique et des experiences developpees au sein du Laboratoire de spectroscopie laser analytique, le principe, les performances, les applications ainsi que les avantages et les inconvenients de ces differentes techniques laser sont presentes, une comparaison est effectuee avec une autre technique (non-laser) analytique performante, la torche a plasma – spectrometrie de masse. Les differentes techniques laser presentees sont en spectroscopie moleculaire : la lentille thermique, la spectrofluorimetrie laser a resolution temporelle, la fluorescence induite par laser de l'iode, et en spectroscopie atomique : la spectroscopie optogalvanique, la fluorescence induite par laser en four de graphite, la fluorescence induite par laser dans une torche a plasma, la spectroscopie d'ionisation resonnante colineaire et l'ionisation laser couplee a la spectrometrie de masse. Les principaux avantages des techniques de spectroscopie laser sont l'absence de preparation d'echantillon, la rapidite, la selectivite, la sensibilite ainsi que la possibilite de pouvoir effectuer des analyses a distance via fibre optique.

A comparison between nitrogen and tripled Nd-YAG laser source for Time-Resolved Laser- Induced Fluorescence (TRLIF) of uranium in nitric acid solutions in the framework of on-line feasibility has been performed. Hence, for uranium on-line monitoring with fiber optics, nitrogen laser (337 nm), most usual source in TRLIF has several drawback; poor beam quality and non negligible nitric acid absorption at 337 nm. Tripled Nd-YAG laser (355 nm) despite lower uranium absorption coefficient has several advantages: no influence of nitric acid absorption, better beam quality, better fiber transmission and solid state technology. No significant difference for fluorescence spectra and lifetimes are observed for both lasers. Limit of detection for direct determination of uranium in nitric acid by TRLIF is in the μ/l (10−8 M) range for both lasers.

Time-Resolved Laser-Induced Fluorescence (TRLIF) is a very sensitive and selective method that has been used for actinides and lanthanides analysis in the nuclear fuel cycle. This technique has been used in different fields such as in geology, in the Purex process, in the environment, in the medical and in waste storage assessment. Spectroscopic data, limits of detection and results obtained in previously quoted fields are presented.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Time-Resolved Laser-Induced Fluorescence (TRLIF) is a very sensitive and selective method that has been used for actinides and lanthanides analysis in the nuclear fuel cycle. This technique has been used in different fields such as in geology, in the Purex process, in the environment, in the medical and in waste storage assessment. Spectroscopic data, limits of detection and results obtained in previously quoted fields are presented.

Time Resolved Laser-Induced Spectrofluorometry (TRLIS) is a ve sensitive and ?' selective method that has been used for actinides and lanthanides analysis in the nuc ear fuel cycle. This technique has been used in different fields such as in geology, in the Purex process, in the environment, in the medical and in waste storage assessment. Spectroscopic data (A excitation, X emission, lifetime), limits of detection and results obtained in previously quoted fields are presented.