This study explores the feasibility of in situ Lithium (Li) analysis in Magnesium-Lithium (MgLi) alloys using Laser-Induced Breakdown Spectroscopy (LIBS). It focuses on two Li emission lines: Li I 670.8 nm (resonance) and Li I 610.
View Article and Find Full Text PDFThis study introduces a novel and simple way to suppress the self-absorption effect in laser-induced breakdown spectroscopy (LIBS) by utilizing a defocusing laser irradiation technique. For this purpose, a Nd:YAG laser with a wavelength of 1,064 nm and repetition rate of 10 Hz with energy in the range of 10 mJ-50 mJ was used. The laser irradiation was focused by using a 150-mm-focal-length plano-convex lens onto the sample surface under defocusing of approximately -6 mm.
View Article and Find Full Text PDFThis study demonstrates a new approach for suppressing the self-absorption effect in single-pulse laser-induced breakdown spectroscopy (LIBS) using unusual parallel laser irradiation. A nanosecond Nd:YAG laser with a wavelength of 1064 nm was fired parallel to and focused at a very close distance of 1 mm to the sample surface. The experiment was carried out in air at atmospheric pressure.
View Article and Find Full Text PDFSelf-absorption, which is known to severely disturb identification of the emission peak intensity in emission-based spectroscopy, was first studied using ordinary single pulse laser-induced breakdown spectroscopy (LIBS). It was found that severe self-absorption, with an evident self-reversal, occurs in the resonance emission lines of high concentration Na, K, and Al, and thus it is impossible to obtain the linear calibration curve required for quantitative analysis. To overcome this problem, we introduce a double pulse orthogonal technique in which the first laser is fired in a parallel orientation at a varied distance of 2-6 mm from the sample surface.
View Article and Find Full Text PDFLaser-induced breakdown spectroscopy (LIBS) to detect the light elements such as lithium (Li) and boron (B) and heavy elements such as copper (Cu) and lead (Pb) in raw fish samples is reported in this work. This is made possible by understanding that the soft target absorbs recoil energy and as a result, the ablated atoms gushing from the soft target do not acquire sufficient speed to form a shock wave. In order to overcome this problem, we set a subtarget on the back of the soft target so as to produce the repulsion force by which the gushing speed of the ablated atoms is increased, yielding a sufficiently high plasma temperature or sufficiently large thermal energy needed for the excitation of the ablated atoms.
View Article and Find Full Text PDFA unique approach for achieving total suppression of the self-absorption effect in laser-induced breakdown spectroscopy (LIBS) has been demonstrated employing a previously published technique of laser-induced plasma spectroscopy utilizing a helium (He) metastable excited state (LIPS-He*).This achievement was attained by the use of the He metastable excited state (He*) and a Penning-like energy transfer mechanism for the delayed excitation of the ablated analyte atoms. KCl and NaCl samples showed the disappearance of the self-absorption emission lines of K I 766.
View Article and Find Full Text PDFThis study is aimed at elucidating the physical processes responsible for the excellent spectral qualities in terms of full width at half-maximum (fwhm) and signal-to-noise (S/N) ratio shown in a special double pulse laser-induced spectroscopy. Apart from the use of atmospheric He ambient gas, the achievement is due to the first laser for generating He gas plasma and the subsequent use of the second laser pulse for target ablation, in opposite order of the two-laser operations in conventional double pulse LIBS. This setup allows adjustments of the many experimental parameters to yield the optimal condition resulting in 0.
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