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Dimethachlon, a dicarboximide fungicide, has gained widespread usage in Asian countries. While considered a low-toxicity fungicide, concerns regarding potential health effects, such as nephrotoxicity, have emerged. To date, neither China nor other countries have established maximum residue limit (MRL) for dimethachlon on grapes, and exposure risk assessment of dimethachlon is lacking. Here, we developed a QuEChERS method coupled with gas chromatography-mass spectrometry (GC–MS) to investigate the dissipation rates and terminal residues of dimethachlon in grapes, along with an assessment of dietary risk to consumers. Our results indicated that the average recoveries of dimethachlon in grapes ranged from 74 to 76%. The limit of quantification (LOQ) was 0.050 mg/kg. After undergoing 112 days of storage at −18 °C, the dissipation rate of dimethachlon in grapes was found to be less than 30%, suggesting a state of stable storage. In the context of good agricultural practice (GAP) guidelines, the half-lives of dimethachlon in grapes were 14.3–18.1 days, which is notably longer compared to the reported values for other crops. The terminal residues of dimethachlon in grapes at 14 and 21 days were found to be < 0.05–0.53 mg/kg and < 0.05–0.29 mg/kg, respectively. Regarding the dietary risk assessment, the calculated risk quotient (RQ) value was significantly below 100%, indicating a negligible chronic risk of dimethachlon in grapes at the recommended dosage. This study provides an important reference for the analysis of dimethachlon and offers valuable empirical data to support the establishment of MRL. [ABSTRACT FROM AUTHOR]

The hydrogen‐bonded organic frameworks (HOFs) have rarely been considered for photocatalytic application, given their weak stability and low activity. One presumably effective strategy to improve the photocatalytic performance of the HOFs is to produce a core–shell composite by fabricating a particular nanostructure using stable HOFs. To this end, the surface‐functionalized metal–organic frameworks (MOFs) are used as the host matrix to support the in situ assembly and subsequent multisite growth of the stable HOFs. MOF@HOF eventually obtains core–shell hybrids, i.e., NH2‐UiO‐66@DAT‐HOF. This newly synthesized core–shell nanostructure exhibits excellent stability and superb photocatalytic performance. For example, in terms of tetracycline degradation, the optimal composite presents an apparent reaction rate constant of 60.7 and 7.6 times higher than its parent materials NH2‐UiO‐66 and DAT‐HOF. Such a pronounced enhancement in photocatalytic efficiency of the hybrid material is attributed to the broader visible‐light utilization range compared to its individual parent material as well as the efficient separation of charge carriers supported by the S‐scheme heterojunction. In addition, it is particularly notable that the photocatalytic efficiency of the yielded core–shell nanostructure can remain high after several‐cycle applications. This work provides a universal scheme for synthesizing the MOF@HOF core–shell hybrids. [ABSTRACT FROM AUTHOR]