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Abstract: Laser-induced breakdown spectroscopy (LIBS) has been applied for quantitative analysis of Cu in algae plants, an issue of paramount importance for environmental monitoring. For the analysis with LIBS, algae were compacted into solid pellets with powdered calcium hydroxide addition as binder and a pulsed Nd:YAG laser was employed to produce the plasmas in air at atmospheric pressure. In this approach, atomic lines from traces of Cu were detected, as well as other major and minor elements. The plasma was characterized and a calibration curve was constructed with reference samples prepared with calcium hydroxide. The results obtained demonstrated the usefulness of the method for Cu monitoring in algae plants. [Copyright &y& Elsevier]

In this paper, a generalized approach is developed and applied for plasma characterization and quantitative purposes in laser-induced breakdown spectroscopy (LIBS) experiences by employing a selected pair of spectral lines belonging to the same multiplet. It is based on the comparison between experimental ratios of line parameters and the theoretical calculus obtained under the framework of a homogeneous plasma in local thermodynamic equilibrium. The applicability of the method was illustrated by using the atomic resonance transitions 279.55–280.27 nm of Mg II, which are usually detected in laser-induced plasma (LIP) during laser ablation of many kinds of targets. The laser induced plasmas were produced using a Nd:YAG laser from a pressed pellet of powdered calcium hydroxide with a concentration of 300 ppm of Mg. The experimental ratios for peak intensities, total intensities and Stark widths were obtained for different time windows and matched to the theoretical calculus. The temperature and the electron density of the plasma, as well as the Mg columnar density (the atom/ion concentration times the length of the plasma along the line-of-sight), were determined. The results were interpreted under the employed approach. [ABSTRACT FROM AUTHOR]

Abstract: Laser Induced Breakdown Spectroscopy has been applied to the analysis of heavy metals in liquid samples, an issue of major importance for environmental monitoring. In this work, a new approach was developed in which liquid solutions were converted into solid pellets of calcium hydroxide by mixing with CaO. Therefore, liquid sample analysis is replaced by solid matrix analysis, overcoming the well-known difficulties and drawbacks of the analysis of liquid samples, and providing additional advantages with respect to other experimental setups. The plasma was produced in air at atmospheric pressure, by a pulsed Nd:YAG laser. Analytical results were achieved for Cr, Pb, Cd and Zn through calibration curves and limits of detection. [Copyright &y& Elsevier]