Determination of the isotopic composition of enriched materials using laser ablation molecular isotopic spectrometry: partial least squares and multivariate curve resolution for the determination of 15N content in enriched urea

A solid substrate based on clay minerals for sampling organic liquids in molecular LIBS analysis

“…These diatomic emitting species are formed later during the evolution of plasma by diverse reaction mechanisms involving atoms, ions, molecules, molecular fragments and clusters, arising from the ablated mass and the surrounding atmosphere. Therefore, a time of 3.0 μs was adopted for gate-delay, as employed by Santos and Pasquini 17 in urea measurements to determine isotopologues of the CN radical. However, under this condition for carbon molecular radicals it was possible to observe strong emission lines of Mg, Al and Si, as shown in Fig.…”

“…Thus, a gate delay of 3.0 μs and a gate width of 10.0 μs were used, based on optimized parameters described by Santos and Pasquini. 17 Measurements were carried out under a constant flow of argon (7.0 L min −1 ), to eliminate interference from atmospheric air and prevent the combustion of flammables. Use of laser safety eyeglasses is compulsory to perform LIBS measurements.…”

Determination of scaling ions in oilfield produced water by laser-induced breakdown spectroscopy

“…The LIBS instrumentation employed in this work is similar to that described by Santos & Pasquini. 34 A Q-switched Nd:YAG laser (Brilliant Quantel B) operating at 1064 nm, with a repetition rate of 20 Hz and pulse duration of 5 ns, was employed. The laser beam was reflected by a dichroic mirror (Ealing Electron-Optics) positioned at 45° and then focused on the sample surface through a BK-7 plano-convex lens with a focal length of 100 mm (Thorlabs).…”

Calibration free laser ablation molecular isotopic spectrometry (CF-LAMIS) for boron isotopic composition determination

“…In earlier studies of LAMIS at atmospheric pressure, the isotopic data were generated for 2 D/ 1 H, 28–31 89 Sr/ 88 Sr, 32 54 Fe/ 56 Fe, 33 15 N/ 14 N, 34 13 C/ 12 C 35 and 10 B/ 11 B 26,36,37 using chemometrics (partial least squares regression) calibration based LAMIS. Sarkar et al reported a precision as high as 9‰(2 σ ) for 10 B/ 11 B using the LAMIS technique.…”