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This study aimed to investigate the effect of ultrasound (US) treatment on the quality maintenance of fresh-cut broccoli during storage. Fresh-cut broccoli was treated ultrasonically at 40 kHz and different power levels (200, 250, 300, 350 and 400 W) for 10 min and then stored at 10 ℃ for up to 96 h. The changes of appearance and microbial load were measured to determine the optimum parameters of US treatment for fresh-cut broccoli. Furthermore, the effect of the optimum US treatment on chlorophyll degradation and the changes in bioactive components in fresh-cut broccoli was studied. The obtained data indicated that US treatments at all power levels tested delayed the increase of yellowing index, L* value, total mold and yeast count and total bacterial count, and inhibited the decrease of H value, the 300 W power being the most effective in maintaining the appearance and microbial quality of fresh-cut broccoli. US treatment at 300 W effectively inhibited the activities of chlorophyllase and Mg-dechelatase, contributing to maintaining higher contents of chlorophyll a, chlorophyll b and total chlorophyll of fresh-cut broccoli. Meanwhile, this treatment maintained higher contents of bioactive ingredients such as vitamin C, total phenols, total glucosinolates and sulforaphane, and improved the scavenging capacity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radicals. Therefore, these results indicated that US treatment could not only effectively slow down the yellowing of fresh-cut broccoli, but also maintain higher contents of bioactive compounds, thus playing a fresh-keeping role.

The challenging issues for the practical application of lithium metal batteries (LMBs) are the fragile solidelectrolyte interphase (SEI) layer and uncontrollable growth of Li dendrites induced by nonuniform Li deposition. In this work, to enable homogeneous Li deposition and a stable SEI layer, a fluorinated gold (Au) doped titanium silicalite (ATSF) is prepared by a facile synthetic process to modify the Cu current collector for a stable Li metal anode. Driven by the Li affinity of Au nanoparticles and microporous properties of titanium silicalite, uniform Li nucleation and homogeneous Li deposition can be realized on the modified Cu current collector. Simultaneously, the doping of fluorine in ATSF facilitates the formation of the LiF-rich SEI layer for a more stable Li stripping/plating process. Consequently, the ATSF5/Cu current collector exhibits a high coulombic efficiency (CE) of 96.8% even after 600 cycles and a long-term cycling stability of 1100 h with remarkably low and stable overpotential. When paired with a high-mass-loading LiFePO4 cathode (∼2.3 mA h cm−2), the Li-metal full cell demonstrates an exceptional capacity retention of 97.9% with a high CE of 99.8% after 200 cycles. Furthermore, the LFP full cell with the Li@ATSF-5/Cu anode also displays superior cycling performance under harsh test conditions. This simple current collector modification through constructing a multi-functional zeolite matrix layer provides a new choice for achieving stable cycling performance of LMBs. [ABSTRACT FROM AUTHOR]