Time-resolved fluorescence spectroscopy light sources

The instrumentation for time-resolved fluorescence spectroscopy shares some similarities with that used for steady-state measurements, in the sense that an excitation source and a detection systems are used. The nature of these components may, and usually does, vary significantly. Namely, a pulsed light source is used in time-resolved spectroscopy, which is at variance with the continuous light source used in steady-state fluorescence. [Pg.824]

Conventional optical absorption spectrometry has detection limits of between 0.01 and 1 mM for the actinides. Highly sensitive spectroscopic methods have been developed, based on powerful laser light sources. Time resolved laser fluorescence spectroscopy (TRLFS), based on the combined measurement of relaxation time and fluorescence wavelength, is capable of speciating Cm(III) down to 10 mol/L but is restricted to fluorescent species like U(VI) and Cm(III). Spectroscopic methods based on the detection of nonradiative relaxation are the laser-induced photoacoustic spectroscopy (LPAS) and the laser-induced thermal leasing spectroscopy (LTLS). Like conventional absorption spectroscopic methods, these newly developed methods are capable of characterizing oxidation and complexation states of actinide ions but with higher sensitivity. [Pg.19]