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Cu-based chalcogenide materials exhibit significant promise for the development of Zn-metal-free anode materials for aqueous Zn-ion batteries (AZIBs). Here, we present the establishment of an efficient and universal strategy that capitalizes on the pyrolysis of copper nanoclusters to fabricate conversion-type Cu7S4 anodes engineered for AZIBs, showcasing outstanding electrochemical performance. Furthermore, by exploiting ligand engineering, we enable the precise control of both the type of molecular fragments generated during nanocluster pyrolysis, thus enabling the manipulation of vacancy concentrations and ion/electron migration in the resultant pyrolysis products. In contrast to the direct pyrolysis of metal salts and ligands, the products derived from copper nanoclusters exhibit enhanced specific capacity, rate performance, and overall stability. This research offers valuable insights for the development of novel electrode materials through the pyrolysis of atomically precise nanoclusters. [ABSTRACT FROM AUTHOR]

This study used a combination method of ultrafine grinding and pregelatinization to modify rice starch (RS) to delay its retrogradation and provide a rationale for prolonging rice product shelf life. The structure and physicochemical properties of the pregelatinized ultrafine grinding rice starch (PURS) were compared with those of RS, ultrafine grinding rice starch (URS), and pregelatinized rice starch (PRS). The microstructure, molecular weight, branched starch length distribution, short‐range order, crystal structure, and physical properties of RS, URS, PRS, and PURS were analyzed, respectively. Results showed that RS, URS, PRS, and PURS granules exhibited similar spherical or polygonal shapes, and the content of amylose and short‐branched starch in PURS increased compared with RS, URS, and PRS. Furthermore, the cross‐polarization of PRS and PURS disappeared. Long‐chain amylopectin and average molecular weight of PURS decreased significantly after ultrafine grinding. Our study suggested reduced breakdown value and setback value and improved gel stability, and PURS was beneficial for delaying retrogradation compared to RS, URS, and PRS. The ultrafine grinding method improved the water swelling capacity (WSC), solubility, pasting properties, and gelation properties of PRS. The hardness of PURS was reduced by ultrafine grinding. These suggest that the combination of ultrafine grinding and pregelatinization could improve the properties of RS. Pearson's correlation analysis showed that the structure of PURS significantly influenced the physicochemical properties. The present study was helpful in better understanding the importance of ultrafine grinding in improving the anti‐retrogradation of PURS and provided new insights into extending the shelf life of rice products by ultrafine grinding and pregelatinization. [ABSTRACT FROM AUTHOR]

Objective To study the imaging characteristics of maxillary sinus effusion in drowned bodies, to explore its morphological characteristics and value in the diagnosis of the cause of death, and to provide objective evidence to support the study of virtual anatomy of drowning. Methods The 154 postmortem CT examination cases （31 cases of drowning, 123 cases of non-drowning） of Beijing Public Security Bureau Forensic Center in 2019 were collected. The bodies of all cases were scanned by multi-layer spiral CT before double-blind reading by clinical imaging experts. Maxillary sinus of corpses with maxillary sinus effusion in imaging findings was punctured. The detection rate of maxillary sinus effusion was calculated. The CT value and volume of maxillary sinus effusion were measured on 3D DICOM workstation. Results The detection rate of maxillary sinus effusion in the drowning was 100%, the shape was horizontal liquid level, the volume was 1.2-11.2 mL, the CT value was 6.08-19.02 Hu, with an average value of 12.85 Hu. The detection rate of maxillary sinus effusion in non-drowning was 19.51% （24/123）, the shape was wavy or irregular, and there were bubbles inside, the volume was 0.4-13.4 mL, the CT value was 23.68-77.75 Hu, with an average value of 42.08 Hu. The differences in CT value between the two groups had statistical significance. Conclusion The postmortem CT examination method can be used to observe the shape and measure the CT value of the maxillary sinus effusion in the bodies in water, which can be an auxiliary examination method for identification of drowning.

Luminescent solar concentrators (LSCs) have the advantages of translucency, color tunability, wide incident light angles, and high weak light sensitivity, so they are attractive for practical applications. Reducing the reabsorption loss and increasing the photoluminescence quantum yield (PLQY) are effective strategies to improve the efficiency of LSCs. However, materials possessing small reabsorption and high PLQY simultaneously are rare. In this work, we demonstrate a strategy to overcome the reabsorption obstacle by the Stokes shift synergistic engineering of active materials. For the first time, we designed and synthesized three new quasi-2D perovskite/PVDF composite films by a room temperature solution processing method. The composite films are able to combine energy-funneling and a positive transient Stark shift to achieve a high PLQY and large Stokes shift. The composite films exhibit high water stability and improved ultraviolet (UV) stability. The large area LSC device with a size of 10 × 10 cm2 exhibits a remarkable external optical efficiency (ηext) of up to 4.9%, which is the highest value reported among organic–inorganic hybrid perovskite LSCs. This work demonstrates that the Stokes shift synergistic engineering of quasi-2D perovskite/PVDF composites is an ideal strategy for constructing efficient and stable LSC devices. [ABSTRACT FROM AUTHOR]

Along with the studies of the properties of optical microcavities, the optical nonlinear effects of the material and the interaction between light and matter are becoming important topics. For example, the chaotic effect of the optical field may appear under the strong laser pumping due to the nonlinear effects. In this study, the chaotic phenomenon of photonic superposed states is investigated in an optomagnonical cavity. Through the dynamic evolution of two-mode photons in the cavity, we found that the energy of the system could be transferred between different modes, and the chaotic behaviour can be tuned by the coupling and the dissipation.