A new analytical strategy was developed that integrates a generic sample preparation into a liquid chromatography-multistage ion trap/time-of-flight mass spectrometry (LC-IT(MS(n))/TOF), allowing for large-scale screening and qualitative confirmation of wide-scope illegal adulterants in different food matrices. Samples were pretreated by a fast single-tube multifunction extraction for accurate multistage mass measurement on the hybrid LC-IT/TOF system. A qualitative validation performed for over 500 analyte-matrix pairs showed the method can reduce most of the matrix effects and achieve a lower limit of confirmation at 0.1 mg/kg for 73% of the target compounds. A unique combination of dual-polarity detection, retention time, isotopic profile, and accurate MS(n) spectra enables more comprehensive and precise confirmation, based on the multiparameter matching by automated library searching against the user-created database. Finally, the applicability of this LC-IT(MS(n))/TOF-based screening procedure for discriminating coeluting isobars, identifying nontarget adulterants, and even tentatively elucidating unexpected species in real samples is demonstrated.

Herein, inspired by previous reports on the electrochemical reduction of Al in diverse electrolyte systems, we describe a novel Al-containing solvate ionic liquid (2:1 (mol/mol) mixture of ethylene carbonate (EC) and AlCl 3 ) that allows low-temperature electrochemical deposition of Al and features the advantages of low cost, ease of preparation, and high electrochemical stability. Electrodeposition of Al-Li alloy and Li can also be realized in this system. Additionally, the above ionic liquid exhibited a saturated vapor pressure of 0.0012 kPa and a conductivity of 1.32 mS/cm at 298 K, which was acceptable for practical applications. To elucidate the electrochemical deposition mechanism, the ionic components of the 2:1 EC/AlCl 3 system were characterized by a range of instrumental analysis techniques and theoretical calculations, and Lewis-acidic cations were identified as the electroactive species for Al electrodeposition. Notably, an Al-Li alloy could be obtained by co-deposition in the new solvate ionic liquid, and Li metal could also be electrodeposited on a high-purity Al plate in the form of Al 4 Li 9 and Li 3 Al 2 under ambient conditions using LiCl as a Li source. Al-containing solvate ionic liquids, which to an extent evolved from organic-salts, are of increasing interest. They are expected to gain more attention in the field of electrochemical metallurgy of active metals, due to their higher tunability and lower price.

In this study, a new electrolyte urea/1-ethyl-3-methylimidazolium chloride was developed to replace traditional sulfuric acid in the zinc electroplating process using zinc oxide as a zinc source. The electrochemical behavior of zinc from zinc oxide was investigated in the urea/1-ethyl-3-methylimidazolium chloride electrolyte using chronoamperometric and cyclic voltammetric techniques. The cyclic voltammograms for this electrolyte illustrated that the zinc reduction is a diffusion-controlled irreversible process via a single-step two-electron transfer procedure. Chronoamperometric measurements suggested that the zinc electrodeposition on a tungsten electrode followed a three-dimensional instantaneous nucleation with a diffusion-controlled growth model at 353 K. Electrodeposits from Chronoamperometric measurements were analyzed with various characterization techniques. SEM images show that electrodeposits were flakes-like at low cathodic potentials and became clusters at more negative cathodic potentials. The obtained electrodeposits are metallic zinc, confirmed by XRD and EDS.

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