Publications by authors named "M A Vargas-Munoz"

This work presents a multisyringe flow injection analysis (MSFIA) system for the automatic extraction and determination of tetracyclines in wastewater samples. The sample was adjusted with NaEDTA buffer before solid-phase extraction with an Oasis HLB column used for the analyte preconcentration. The europium (Eu)-based and citrate-mediated method (using Tris-HCl buffer) was selected for the fluorimetric analysis (λ = 400/612 nm).

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This paper presents data on free-living ticks collected by flagging and using CO traps in three natural areas in Costa Rica: Carara National Park (CNP), Palo Verde National Park (PVNP), and a Private Forest Reserve in Sarapiquí (SPR). Data were analyzed calculating aspects of alpha diversity (species richness, entropy; dominance index, and evenness); and for beta diversity, compositional similarity between communities of ticks was also calculated. We collected 12,795 ticks belonging to 10 species: Amblyomma coelebs, Amblyomma dissimile, Amblyomma mixtum, Amblyomma naponense, Amblyomma cf.

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Article Synopsis
  • Long-chain fatty acids (LCFA) are significant in lipid-rich wastewaters and need to be analyzed effectively in anaerobic digesters.
  • A new method combining in-syringe magnetic stirring-assisted dispersive liquid-liquid microextraction (DLLME) with gas chromatography-mass spectrometry (GC-MS) allows for rapid and precise LCFA analysis without needing derivatization.
  • This method shows excellent detection limits (0.01-0.05 mg L) and precision, successfully identifying palmitic, stearic, and oleic acids in samples from anaerobic digesters and olive mill wastewaters.
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Volatile fatty acids (VFAs) are key parameters to monitor anaerobic digestion processes. Thus, a fast, simple and precise determination of these analytes is necessary for a timely characterization of the biological processes present in municipal solid waste and wastewater treatment plants. In this work, an automated method for the extraction and preconcentration of VFAs, based on dispersive liquid-liquid microextraction with magnetic stirring in syringe, and gas chromatography with flame ionization detector for the separation and detection, is described.

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