A novel time-resolved laser fluorescence spectroscopy system for research on complexation of uranium(IV)

Applications of laser spectroscopy in nuclear research and industry

“…Detection can be improved by using picosecond pulsed lasers and a fast response detection device. More recently, the fl uorescence of U(IV) has been detected and analyzed by TRLIF using excitation with femtoseconds pulse laser, and a spectrometer that can record emissions in the UV-Visible region (Kirishima et al , 2003(Kirishima et al , , 2004Lehmann et al , 2009). Table 17.1 summarizes the main characteristics of TRLIF for these actinide species.…”

Applications of Time-Resolved Laser Fluorescence Spectroscopy to the Environmental Biogeochemistry of Actinides

“…Traditional laser systems include the pulsed neodymium‐doped yttrium aluminum garnet (Nd:YAG) laser (Tan et al, 2008) or excimer laser (Kimura and Choppin, 1994; Schmidt et al, 2009). During the last decade, optical parametric oscillators pumped by Nd:YAG lasers have become increasingly state‐of‐the‐art (Heller et al, 2009; Lehmann et al, 2009; Wang et al, 2005b; Wang et al, 2004). Nitrogen gas (Moulin et al, 1995) and titanium‐doped sapphire (Ti:sapphire) (Stumpf et al, 2002b) lasers have also featured prominently in TRLFS studies.…”

“…Mean pulse profiles from all these systems, except for Ti:sapphire lasers, are approximately 5 to 15 ns full width at half maximum, with 0.1 to 10 mJ per pulse at a fixed repetition rate of 5 to 20 Hz. To analyze (i) the effect of actinide ions on organic ligand fluorescence during metal complexation or (ii) the species of U 4+ , Am 3+ , and Bk 3+ , all of which have very short fluorescence decay lifetimes of several nanoseconds, ultra‐short pulsed lasers, such as a Ti:sapphire laser, with regenerative amplifiers having ∼130 fs pulse profiles, >4 mJ per pulse laser power, and 1 kHz repetition rates are required (Aoyagi et al, 2004; Geipel et al, 2004; Toraishi et al, 2004), although an optical parametric oscillator system pumped by a Nd:YAG laser has recently been used to detect U 4+ at concentrations >5 × 10 −7 mol L −1 (Lehmann et al, 2009).…”

“…The fluorescence emitted from the excited metal ions in TRLFS are now routinely measured with optical multichannel analyzers consisting of a Czerney‐Turner type polychromator spectrograph with 50, 300, 600, 1200 grooves per mm grating and an intensified charged‐couple device (ICCD) camera (Grossman et al, 2009; Lehmann et al, 2009; Saito et al, 2010; Toraishi et al, 2004). Synchronization between the laser pulse and an electronic trigger to the ICCD camera is performed using a delay generator or optical delay circuits (Grossman et al, 2009; Lehmann et al, 2009). Although ICCD systems are limited to time resolution in the order of nanoseconds, shorter fluorescent decay lifetimes can be measured when using a femtosecond laser pulse with a streak camera or pump‐and‐probe method (Mizuno et al, 2005; Toraishi et al, 2004).…”

“…The recent development of ultra‐fast TRLFS systems (Aoyagi et al, 2004; Geipel et al, 2004; Lehmann et al, 2009) and the wider application of TRLFS at cryogenic or liquid nitrogen temperatures (Duff et al, 2000; Wang et al, 2005b; Wang et al, 2004; Wang et al, 2008b), which can increase decay lifetimes, have significantly expanded the range of actinide ions that may be analyzed with this advanced spectroscopic technique. Although applications have been limited to speciation analyses of the U 4+ , UO 2 + , and UO 2 2+ ions (Duff et al, 2000; Geipel et al, 2004; Grossman et al, 2009; Kirishima et al, 2003; Lehmann et al, 2009), significant potential exists for characterizing the speciation of other important nuclear fuel cycle actinides that have extremely short fluorescence decay lifetimes, such as americium (Am 3+ ), in biogeochemical studies.…”