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It is still a great challenge to develop effective strategies to improve the low electrogenerated chemiluminescence (ECL) of air-saturated luminol. Herein, the synergistic effects of Ti3C2-TiO2-AuNPs nano hybrid and high-intensity focused ultrasound pretreatment (ultrasound-pretreatment) were used to significantly improve the ECL emission of the air-saturated luminol, and the mechanism was proposed. The ultrasound-pretreatment as a green method with the cavitation effect could form O2–• and H2O2 in situ as an initiator. TiO2 and Au nanoparticles (AuNPs) were in situ decorated on the Ti3C2 surface to form Ti3C2-TiO2-AuNPs, and it was proved as a highly efficient booster which could catalyze and aggregate H2O2 to the O2–•. The utilization rate of intermediates has been greatly improved. Exosomes as model targets can be sensitively detected by the ECL sensor. The detection limit was 195 particles μL−1. The detection results of exosomes in actual samples are satisfactory. We believe that the ultrasound-pretreatment strategy could be extended to the sensitive detection in the biological sample.

Catalysis covers almost all the chemical reactions or processes aiming for many applications. Sonochemistry has emerged in designing and developing the synthesis of nano-structured materials, and the latest progress mainly focuses on the synthetic strategies, product properties as well as catalytic applications. This current review simply presents the sonochemical effects under ultrasound irradiation, roughly describes the ultrasound-synthesized inorganic nano-materials, and highlights the sonochemistry applications in the inorganics-based catalysis processes including reduction, oxidation, degradation, polymerization, etc. Or all in all, the review hopes to provide an integrated understanding of sonochemistry, emphasize the great significance of ultrasound-assisted synthesis in structured materials as a unique strategy, and broaden the updated applications of ultrasound irradiation in the catalysis fields.

In order to cope with the continuous development of information technology, the data volume of edge devices in the power supply network is increasing rapidly, and the higher requirements for real-time data processing and transmission bandwidth are put forward, the author proposes the research on security protection of multi-source data in smart grid based on edge computing. Established a distribution network safety risk map, calculated and analyzed safety risks through potential functions, and obtained node potential values and key node data; The intelligent grid multi-source heterogeneous data monitoring model based on edge computing can realize the timely perception and real-time response of distribution network faults, shorten the outage time, and improve the power supply reliability and user satisfaction of the distribution network. The results indicate that: Taking a distribution network line in a certain area as an example, the highest potential value is node 9, followed by nodes 10 and 3. This indicates that in order to ensure the reliable operation of the distribution network and avoid power outages, it is necessary to improve the repair capacity, the proportion of old equipment, and the power supply radius exceeding the standard. Conclusion: The effectiveness of potential function in risk assessment of edge computing is verified, which can provide theoretical guidance for distribution network fault diagnosis.

Purpose: Type 2 diabetes mellitus (T2DM) is associated with a greater risk of Alzheimer's disease. Synaptic impairment and protein aggregates have been reported in the brains of T2DM models. Here, we assessed whether neurodegenerative changes in synaptic vesicle 2 A (SV2A), γ-aminobutyric acid type A (GABAA) receptor, amyloid-β, tau and receptor for advanced glycosylation end product (RAGE) can be detected in vivo in T2DM rats. Methods: Positron emission tomography (PET) using [18F]SDM-8 (SV2A), [18F]flumazenil (GABAA receptor), [18F]florbetapir (amyloid-β), [18F]PM-PBB3 (tau), and [18F]FPS-ZM1 (RAGE) was carried out in 12-month-old diabetic Zucker diabetic fatty (ZDF) and SpragueDawley (SD) rats. Immunofluorescence staining, Thioflavin S staining, proteomic profiling and pathway analysis were performed on the brain tissues of ZDF and SD rats. Results: Reduced cortical [18F]SDM-8 uptake and cortical and hippocampal [18F]flumazenil uptake were observed in 12-month-old ZDF rats compared to SD rats. The regional uptake of [18F]florbetapir and [18F]PM-PBB3 was comparable in the brains of 12-month-old ZDF and SD rats. Immunofluorescence staining revealed Thioflavin S-negative, phospho-tau-positive inclusions in the cortex and hypothalamus in the brains of ZDF rats and the absence of amyloid-beta deposits. The level of GABAA receptors was lower in the cortex of ZDF rats than SD rats. Proteomic analysis further demonstrated that, compared with SD rats, synaptic-related proteins and pathways were downregulated in the hippocampus of ZDF rats. Conclusion: These findings provide in vivo evidence for regional reductions in SV2A and GABAA receptor levels in the brains of aged T2DM ZDF rats.

The microstructural features of long period stacking ordered (LPSO) phase in Mg–(11-x)Gd–xY–1Zn–0.3Zr (wt.%) alloys were optimized by adjusting Gd/Y ratios to10:1, 8:3, 6:5, 4:7 and 2:9, respectively. Superior high-temperature strength was successfully obtained in the extruded 6Gd–5Y alloy with ultimate tensile strength (UTS) values of 338 MPa and 286 MPa at 250 °C and 300 °C, respectively. In the as-cast alloys, with the decrease of Gd/Y ratio, the type of intermetallic compound gradually changed from (Mg, Zn)3(Gd, Y) (W) to LPSO phase. After homogenization, the W phase was completely converted to LPSO phase except for the 10Gd–1Y alloy. Importantly, the block-shaped LPSO phases with the smallest size and the abundant lamellar LPSO phases were formed in the 6Gd–5Y alloy, which significantly influenced the microstructures of the extruded alloy. Firstly, the small sized block-shaped LPSO phase before extrusion provided favorable conditions for the formation of thin plate-shaped LPSO phase at DRXed regions, which effectively hindered the grain boundary migration at high temperature due to superior thermal stability. Secondly, the profuse lamellar LPSO phases prior to extrusion contributed to the highest density of low angle grain boundaries (LAGBs) and residual dislocations in the extruded 6Gd–5Y alloy, which obstructed dislocation slip at elevated temperatures. In addition, the abundant lamellar LPSO phase also caused the fine DRXed grain size and strong basal texture to enhance the high-temperature strength of the extruded 6Gd–5Y alloy.

In this work, novel turned-bearing extrusions (TBE) conducted by using the dies with the single corner and double corner, named SC-TBE and DC-TBE respectively, are developed to introduce additional shear strain during the preparation of AZ31 alloy sheets, which is expected to improve the strengths of sheets. Numerical simulations are conducted to uncover the effect of additional shear deformation on the microstructure during the TBE. The results show that the high strain during the TBE leads to a high nucleation rate for dynamic recrystallization (DRX), resulting in grain refinement of the extruded Mg alloy sheet. However, the high strain also increases the temperature of the material due to the heat generated by plastic deformation, which provides a great driving force for grain growth and consumes dislocations. As these two effects compete with each other when increasing the strain near the die orifice, the SC-TBE sheet has finer grains and a higher residual dislocation density compared to the DC-TBE sheet or the sheet prepared by the conventional extrusion (CE). Fine-grain strengthening and substructure strengthening work together and enhance the tensile yield strength (TYS) of the SC-TBE sheet. The TYSs along extrusion direction (ED), transverse direction (TD) and 45° direction (the half angle between ED and TD) of the SC-TBE sheet are improved by 32 MPa, 65 MPa and 35 MPa respectively compared with the CE sheet. The findings of this research provide some new insights into the development of new preparation methods for Mg alloy sheets with higher strength.