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    The second ACTRIS inter-comparison (2016) for Aerosol Chemical Speciation Monitors (ACSM): Calibration protocols and instrument performance evaluations
    (Philadelphia, Pa.: Taylor & Francis, 2019) Freney, Evelyn; Zhang, Yunjiang; Croteau, Philip; Amodeo, Tanguy; Williams, Leah; Truong, François; Petit, Jean-Eudes; Sciare, Jean; Sarda-Esteve, Roland; Bonnaire, Nicolas; Arumae, Tarvo; Aurela, Minna; Bougiatioti, Aikaterini; Mihalopoulos, Nikolaos; Coz, Esther; Artinano, Begoña; Crenn, Vincent; Elste, Thomas; Heikkinen, Liine; Poulain, Laurent; Wiedensohler, Alfred; Herrmann, Hartmut; Priestman, Max; Alastuey, Andres; Stavroulas, Iasonas; Tobler, Anna; Vasilescu, Jeni; Zanca, Nicola; Canagaratna, Manjula; Carbone, Claudio; Flentje, Harald; Green, David; Maasikmets, Marek; Marmureanu, Luminita; Cruz Minguillon, Maria; Prevot, Andre S.H.; Gros, Valerie; Jayne, John; Favez, Olivier
    This work describes results obtained from the 2016 Aerosol Chemical Speciation Monitor (ACSM) intercomparison exercise performed at the Aerosol Chemical Monitor Calibration Center (ACMCC, France). Fifteen quadrupole ACSMs (Q_ACSM) from the European Research Infrastructure for the observation of Aerosols, Clouds and Trace gases (ACTRIS) network were calibrated using a new procedure that acquires calibration data under the same operating conditions as those used during sampling and hence gets information representative of instrument performance. The new calibration procedure notably resulted in a decrease in the spread of the measured sulfate mass concentrations, improving the reproducibility of inorganic species measurements between ACSMs as well as the consistency with co-located independent instruments. Tested calibration procedures also allowed for the investigation of artifacts in individual instruments, such as the overestimation of m/z 44 from organic aerosol. This effect was quantified by the m/z (mass-to-charge) 44 to nitrate ratio measured during ammonium nitrate calibrations, with values ranging from 0.03 to 0.26, showing that it can be significant for some instruments. The fragmentation table correction previously proposed to account for this artifact was applied to the measurements acquired during this study. For some instruments (those with high artifacts), this fragmentation table adjustment led to an “overcorrection” of the f44 (m/z 44/Org) signal. This correction based on measurements made with pure NH4NO3, assumes that the magnitude of the artifact is independent of chemical composition. Using data acquired at different NH4NO3 mixing ratios (from solutions of NH4NO3 and (NH4)2SO4) we observe that the magnitude of the artifact varies as a function of composition. Here we applied an updated correction, dependent on the ambient NO3 mass fraction, which resulted in an improved agreement in organic signal among instruments. This work illustrates the benefits of integrating new calibration procedures and artifact corrections, but also highlights the benefits of these intercomparison exercises to continue to improve our knowledge of how these instruments operate, and assist us in interpreting atmospheric chemistry. © 2019, © 2019 Author(s). Published with license by Taylor & Francis Group, LLC.
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    Nuevo sistema integrado cromatografía líquida de alta resolución / nebulizador hidráulico de alta presión y temperatura (HPLC/HT-HHPN) para la separación automática de la matriz en la determinación de metales en salmueras con espectrometría de absorción atómica (FAAS)
    (Sao Paulo : Scielo, 2000) Yáñez, J.; Berndt, H.
    An integrated HPF-system using HPLC and HT-HHP-nebulizer is used for matrix separation by the determination of heavy metals in highly concentrated solutions with FAAS. The separation of the matrix (NaCl) is achieved in a HPLC RP-C18 column after heavy metal complexing with trans-1,2-diaminciclohexane-N,N,N ,N -tetraacetic acid (CDTA). Matrix separation and the metal determination can be realized in less than one minute, without any interference from the matrix. The detection limits of Cd(II), Co(II), Cr(VI), Cu(II), Mn(II) and Zn(II) by FAAS were improved in one order of magnitude in compare with the direct determination by pneumatic nebulization nebulizer.
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    Special issue on “Ultrasound-assisted engineering of materials for biomedical uses”
    (Amsterdam [u.a.] : Elsevier Science, 2022) Besford, Quinn A.; Cavalieri, Francesca
    [no abstract available]
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    Author Correction: Surface acoustic wave nebulization improves compound selectivity of low-temperature plasma ionization for mass spectrometry
    (London : Nature Publishing Group, 2021) Kiontke, Andreas; Roudini, Mehrzad; Billig, Susan; Fakhfouri, Armaghan; Winkler, Andreas; Birkemeyer, Claudia
    Correction to: Scientific Reports https://doi.org/10.1038/s41598-021-82423-w, published online 03 February 2021