Publications by authors named "M A Meneses-Nava"

Laser-induced breakdown spectroscopy is presented for trace element detection of liquid samples by analyzing a single droplet levitated by ultrasonic waves. A single liquid droplet is placed in the node of a standing acoustic wave produced by a uniaxial levitator for further chemical analysis. The acoustic levitator consists of a commercial Langevin-type transducer, attached to a concave mechanical amplifier, and a concave reflector.

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This work proposes a method to perform elemental identification on plasmas produced using the laser-induced breakdown spectroscopy (LIBS) technique. The method is based on the preservation of the relative relevance of the spectral line emission intensities, which is lost during the parametric correlation procedure, by the introduction of a similitude coefficient called wavelength similarity coefficient. Furthermore, it was shown that for identification purposes, a simplified plasma model is sufficient to predict adequately the relative emission intensities in LIBS plasmas.

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In this Research Article, the effect of two techniques for top-electrode deposition in organic photovoltaics (OPVs) cells with the configuration ITO/PEDOT:PSS/PTB7-Th:PCBM/PFN/top-electrode is analyzed. One deposition was made by evaporation under high vacuum, meanwhile the other was carried out at normal room atmosphere; for the former, a double layer of Ca and the eutectic alloy Field's metal (FM) was thermally evaporated, while for the latter FM was deposited just by melting and dropping it on top of the delimited active area at temperatures about 90 °C. The average short-circuit photocurrent density, open circuit voltage and fill factor for devices with either Ca/FM (evaporated) or FM (by dripping) cathode, were very similar: around 13.

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The use of double-pulse laser-induced breakdown spectroscopy (DP-LIBS) in quantitative analysis generally depends on standards and calibration curves. To our knowledge, in this Letter, we report the first quantitative analysis based on DP-LIBS at low ablative energies with a self-calibrated method. We compare the effects of plasmas on the calibration-free LIBS technique, generated by DP-LIBS, and the traditional single-pulse (SP) LIBS on a steel sample.

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Laser-induced breakdown spectroscopy (LIBS) is evaluated as a potential analytic technique for rapid screening and quality control of anti-diabetic tablets. This paper proposes a simple LIBS-based method for the quantitative analysis of two active pharmaceutical ingredients (APIs): metformin (Met) and glybenclamide (Gly). In order to quantify both APIs, chlorine (Cl) concentration was estimated by employing the Cl/Br optical emission ratio, where Br was introduced as internal standard.

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