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A simple cost-effective laser-induced breakdown spectroscopy (LIBS) instrument was used for quantification of major elements in several nickel alloys and also sorting them. A compact low-power diode-pumped solid-state laser and a miniature low-resolution spectrometer were assembled for the LIBS instrument. Material properties of the nickel alloys depend mainly on the composition of the major elements, Ni, Cr, and Fe, ranging from a few to ∼60 wt%. The emission peaks at 547.7 nm, 520.4 nm, and 438.1 nm for Ni, Cr, and Fe, respectively, were chosen for this analysis. The analytical performance was found to be enough for the quantification of Ni, Cr, and Fe in the nickel alloys. Limits of detection and accuracy were estimated to be a few weight percent (wt%) and measurement precisions were less than 10% in terms of relative standard deviation. The calibration performance of this intensity-based method was compared with that of the “ratio method” which is used in conventional optical emission spectroscopy analyses. The comparison indicates that the intensity-based method is more appropriate with the low-performance LIBS instrument that detects emission peaks of only a few major elements. Also, multivariate modeling of the six different nickel alloy samples based on the emission peak intensities of Ni, Cr, and Fe was performed using k-nearest neighbors (KNN) and linear discriminant analysis (LDA). The KNN and ordinary LDA models showed 95.0% and 98.3% classification correctness for the separate test data set, respectively. To improve classification performance further, the two-step LDA model was trained. In this approach, the two closest sample classes responsible for the decrease in the classification correctness were separately modeled in the second step to exploit their difference effectively. The two-step LDA model showed 100% correctness in classifying the test objects. Our results indicate that such a low-performance LIBS instrument can be effectively utilized for quantitative analysis of the major elements in the nickel alloys and their rapid identification or sorting in combination with an appropriate multivariate modeling algorithm.

Laser-induced breakdown spectroscopy (LIBS) and near-infrared (NIR) spectroscopy, enabling the measurement of raw bile directly without sample pretreatment, were cooperatively combined to enhance the discrimination of gallbladder cancer (GBC) from other diseases of gallstone and gallbladder (GB) polyp. Since elemental contents and metabolite compositions of bile vary according to the pathological conditions of pancreaticobiliary patients, the use of complementary information could be synergetic to improve disease identification accuracy. The ratios of Mg and Na peak areas (

Ceria doped with low-valence lanthanide cations has been introduced for use as an electrolyte in solid oxide fuel cells (SOFCs). Improving the performance of SOFCs using doped ceria requires an increase in ion mobility across the solid electrolyte. Recently, ceria doped with multiple low-valence lanthanide ions has been found to show better ion mobility than that of the singly doped one. In this work, the feasibility of laser-induced breakdown spectroscopy (LIBS) for stoichiometric analysis of doubly doped ceria, Sm

Laser-induced breakdown spectroscopy (LIBS) was explored for the first time for discrimination of gallbladder (GB) polyp and GB cancer (GBC) by direct measurement of raw bile juice without pretreatment.

Laser-induced breakdown spectroscopy (LIBS) and near-infrared (NIR) spectroscopy were combined to enhance discrimination of soybean paste samples according to geographical origin. Since element and organic component compositions of soybean pastes depend on soybean cultivation areas and fermentation conditions, utilization of two complementary spectroscopic signatures would be synergetic for the discrimination. When the areas of C (A

Gadolinium-doped ceria (GDC) is a functional ceramic material used for the electrolytes and electrodes in solid oxide fuel cells (SOFCs). As the more SOFCs are used in power generation, a demand on the practical and reliable analytical methodology for GDCs would increase further. In this work, we investigated feasibility of the laser-induced breakdown spectroscopy (LIBS) instrument assembled with a compact low-power diode-pumped solid-state laser and a hand-held low-resolution spectrometer for stoichiometric analysis of GDCs. LIBS uses laser ablation sampling that greatly simplifies the sample preparation process by removing acid digestion, high temperature treatment, and further dilution indispensable for conventional elemental analyses. In the observed wavelength region of 397 – 450 nm, Gd and Ce poured out rich emission lines and those were unable to be resolved by the low-resolution spectrometer. However, the characteristic spectral features of Gd and Ce were successfully extracted from the unresolved spectra and well correlated with the mole fractions of Gd in GDCs by means of partial least squares-regression (PLS-R). Our results indicate that the low-performance LIBS instrument and PLS-R calibration can be a cost-effective practical technique for stoichiometric analysis of GDCs.