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In this study, the enantioselective dissipation behavior of hexaconazole was investigated in cucumber fruit, head cabbage, and two different types of agricultural soils. The dissipation kinetics was determined by reverse-phase liquid chromatography-tandem mass spectrometry on a cellulose tris (3-chloro-4-methylphenylcarbamate) chiral column. Dissipation rates of hexaconazole enantiomers followed first-order kinetics; the residues of (+)-enantiomer decreased more rapidly than (-)-enantiomer in cucumber and head cabbage, resulting in relative enrichment of the (-)-form, while the two enantiomers showed similar degradation rates in the tested soils. These results indicate substantial enantioselectivity in the residue dissipation of hexaconazole enantiomers in cucumber and head cabbage; however, nonenantioselective dissipation was observed in the tested soils.

The increasing significance on the development of high-performance lithium-ion (Li-ion) batteries is calling for new battery materials, theoretical models, and simulation tools. Lithiation-induced deformation in electrodes calls attention to study the multiphysics coupling between mechanics and electrochemistry. In this paper, a simultaneous multiscale and multiphysics model to study the coupled electrochemistry and mechanics in the continuum battery cell level and the microscale particle level was developed and implemented in comsolmultiphysics. In the continuum scale, the porous electrode theory and the classical mechanics model were applied. In the microscale, the specific particle structure has been incorporated into the model. This model was demonstrated to study the effects of mechanical constraints, charging rate, and silicon/C ratio, on the electrochemical performance. This model provides a powerful tool to perform simultaneous multiscale and multiphysics design on Li-ion batteries, from the particle level to full-cell level.

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