Calibration strategies for determination of the In content in discarded liquid crystal displays (LCD) from mobile phones using laser-induced breakdown spectroscopy (LIBS)

Geochemical and Biological Profiles of a Quartz Stone in the Qaidam Mars Analog Using LIBS: Implications for the Search for Biosignatures on Mars

“…Following data processing techniques described in previous LIBS microbiological studies, all peaks from 200 to 900 nm , were normalized to total peak intensity of LIBS spectra to prevent inconsistencies caused by excitation or emission angles. − PCA was performed for LIBS data based on the correlation matrix of all normalized peak intensities using R software (v4.1.2) . The two-dimensional PCA technique fitted all measurements in a real coordinate space by minimizing the average squared perpendicular distance from points to the component axis.…”

Direct determination of Al and Pb in waste printed circuit boards (PCB) by laser-induced breakdown spectroscopy (LIBS): Evaluation of calibration strategies and economic - environmental questions

“…The study of waste electrical and electronic equipment (WEEE) generation is therefore of great interest due to the environmental, economic, recycling and reuse questions posed by this type of waste (Costa et al 2018a, Tansel, 2017. According to a study published in 2017, the projection of WEEE production is expressive (Andrade et al 2019a(Andrade et al , 2019b(Andrade et al , 2019c(Andrade et al , 2019d), being 52.2 million tons in 2021 (Baldé et al 2017). WEEE contains a diverse, complex and valuable composition, consisting mainly of polymers, metals (base, toxic, noble and technological elements) and ceramics.…”

“…Printed circuit boards (PCB), which are part of the electronic devices present in the WEEE, contain large amounts of valuable and dangerous metals such as, for example, Al and Pb. Depending on the electronic device, the metal content on PCBs can range from 2 to 19% Al and 1 to 3% Pb, among others (Andrade et al 2019b, Arshadi et al 2018, Carvalho et al 2015, Perkins et al 2014, Yamane et al 2011, Yang et al 2019. Aluminum and Pb can be recycled, adding value to the WEEE and generating a source of income.…”

“…In order to overcome these matrix effects, univariate and multivariate calibration strategies are used for LIBS: matrix-matching calibration (MMC) (Costa et al 2018b, Gomes et al 2013, Vieira et al 2018), standard addition (SA) (Yi et al 2016, one-point gravimetric standard addition (OP GSA) (Babos et al 2019), internal standardization (IS) (Aquino et al 2016, Carvalho et al 2018b, Lasheras et al 2013) calibration free (CF) (Calvacante et al 2013, Ciucci et al 1999, Tognoni et al 2010, one-point and multi-line calibration (OP MLC) (Hao et al 2018), multi-energy calibration (MEC) (Andrade et al 2019b, Babos et al 2018, Carvalho et al 2019, Castro et al 2020, Fortunato et al 2019, twopoint calibration transfer (TP CT) (Castro et al 2020), and single-sample calibration (SSC) (Yan et al 2019).…”

Introducing multi-energy ratios as an alternative to multi-energy calibration for Br determination via high-resolution continuum source graphite furnace molecular absorption spectrometry. A case study

“…The advantage of obtaining multiple signals from every aliquot replaces the need to prepare and measure many standards. This approach was labelled multi-energy calibration (MEC) and it has been used for atomic emission techniques such as inductively coupled plasma optical emission spectrometry (ICP OES), 10 microwave-induced plasma optical emission spectrometry (MIP OES) 10,11 and laser-induced breakdown spectrometry, [12][13][14][15][16] as well as for atomic absorption processes, namely high-resolution continuum source flame atomic absorption spectrometry (HR CS FAAS), 10 high-resolution continuum source molecular absorption spectrometry (HR CS MAS) 17 and molecular absorption in the ultraviolet-visible region of the spectra, in addition to fluorescence. 18 The same principle has also been applied to inductively coupled plasma mass spectrometry (ICP-MS) by monitoring different isotopes from the same element, 19,20 and then it has been referred to as multi-isotope calibration.…”