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As the planning and dispatching of new types of power systems become increasingly complicated， dynamic and dubious， it is very challenging to lay down operating mode for power grid that satisfies both security and economic constraints. This process typically requires intensive manual tuning and simulation calculations to search for feasible solutions in a high-dimensional action space that fulfills the requirements on safety and economy of the grid in ground state and fault conditions. Therefore， an approach based on multi-DRL-agent architecture is proposed to describe the problem as a Markov decision process （MDP）. The approach automatically adjusts different types of controllable grid resources by training centralized and distributed multi-DRL-agent to control the power of transmission lines， thus complying with various safety indicators of grid operation. The method is proved to be effective in a power grid model.

The critical experimental device with spent fuel can be used to carry out critical experimental research on spent fuel storage. Considering its high radioactivity，the best way to carry out the experiment is to take the method of extrapolating water level to criticality. At present, the critical experimental device with spent fuel has not been built yet, thus the simulation experiment of water level extrapolation is carried out in a critical experimental device with similar core structure and physical characteristics, which is a uranium rod grid device with light water as moderator. In this experiment, the normal extrapolation curve cannot be obtained because of the shielding effect of water deepens with the rise of water level. In this paper, the extrapolation process was simulated by Monte Carlo program, and the characteristics of neutron count rate changing with water level were studied when the neutron source and detector were arranged in different relative positions, thus the optimal arrangement scheme of detector and neutron source was given. In addition, an extrapolation method with water level worth as extrapolation parameter was proposed, which eliminates the influence of uneven water level coefficient when extrapolating to criticality with water level, and makes the extrapolation result more accurate.

Three‐coil inductive power transfer (IPT) charging system can not only achieve inherent constant current (CC) to constant voltage (CV) transition but also tolerate load open‐circuit. However, due to the cross‐coupling between the auxiliary coil and the receiver coil, the output voltage in CV mode may deviate from the CV voltage significantly, which makes the design freedom of the three‐coil coupler low. By replacing the auxiliary coil with a transformer, an improved auxiliary circuit is proposed in this paper to address the cross‐coupling issue and to increase the design freedom of the loosely coupled transformer (LCT). The improved auxiliary circuit can achieve load short‐circuit and open‐circuit protection. Besides, the optimization design of LCT is easy to achieve by load impedance matching. The operating principle and parameters design of the improved auxiliary circuit are discussed. A 1 kW experimental prototype is built to verify the feasibility of the proposed method. [ABSTRACT FROM AUTHOR]

Dickeya dadantii is a common pathogen of bacterial soft rot on a wide range of plants, including several crops. In this study, we present the complete genome sequence of the D. dadantii type strain DSM18020T. The genome was assembled using PacBio technology, resulting in a 4,997,541 bp circular chromosome with a G+C content of 56.5%. Our sequence analyses predicted 4277 protein-encoding genes, including several associated with known bacterial virulence factors and secondary metabolites. Comparative genomics analysis between Dickeya revealed that the category of 'metabolism' is the most important in both the core and accessory genomes, while the category of 'information storage and processing' is the most dominant in unique genomes. These findings will not only help us to understand the pathogenic mechanisms of D. dadantii DSM18020T, but also provide us with useful information for new control strategies against this phytopathogen. [ABSTRACT FROM AUTHOR]

A ethylene - octene copolymer (OBC)/waste polystyrene (WPS) compatibilizing masterbatch was prepared through the Friedel-Crafts alkylation reaction. The effects of anhydrous; AlCl3 dossage on the grafting rate of WPS and the properties of the masterbatch and the effects of the masterbatch dosage on the comprehensive performance of ethylene -propylene-diene rubber (EPDM) were investigated. The results indicated that WPS could react with OBC to form an OBC-g-WPS graft copolymer. There was no gelation at an anhydrous AlCl3 dosage of 0. 4 and a WPS grafting rate of 25. 3 wt%, resulting in the best comprehensive properties of the masterbatch. When this compatibilizing masterbatch was used for EPDM, the resultant rubber exhibited higher tensile strength, higher tear strength, and better heat aging resistance than pure EPDM vulcanized rubber, and its performance was also better than that of the EPDM containing the same amount of an OBC/WPS physical blend. Scanning electron microscopy indicated that WPS was uniformly dispersed in the vulcanized EPDM rubber with the addition of the OBC/WPS compatibilizing masterbatch. [ABSTRACT FROM AUTHOR]

Traditional optical communication using single narrow-band photodetectors (PDs) has poor confidentiality because all information and data are exposed to free space. With the development of science and technology, even the optical communication in the solar-blind ultraviolet (UV) band carries the risk of eavesdropping. Dual-band PDs have potential applications in secure and reliable optical communication through a combination of optical encryption and algorithmic encryption. In this paper, self-powered Cu2O/Ga2O3 heterojunction PDs with solar-blind UV-visible photodetection were fabricated. By adjusting the pH value of the Cu2O electrolyte, the crystallization quality and grain orientation of the Cu2O thin film were improved, and the interface transfer resistance of the heterojunctions was decreased. The Cu2O/Ga2O3 PDs fabricated in Cu2O electrolyte with a pH value of 9.5 demonstrated the optimized solar-blind UV-visible photoresponse characteristics. In the absence of applied bias, the device exhibited a responsivity of 0.12 mA W−1, a rise time of 2.48 ms and a fall time of 11.72 ms at 254 nm. The responsivity reaches 19 mA W−1 when illuminated at 475 nm, and the rise and fall times are 0.96 and 9.12 ms, respectively. Utilizing the excellent photoresponse characteristics of the solar-blind UV-visible band, the device was used to design and demonstrate a proof-of-concept optical communication system for secure data transmission. The proposed system features two independent light channels, utilizing solar-blind UV light as the information carrier and visible light for key transmission. By implementing specific algorithms, this design ensures safe and reliable communication. [ABSTRACT FROM AUTHOR]

AbstractIn order to improve the hardness of the copper surface, reduce its friction coefficient, and adjust the overall performance of the coating, a TiB2/Cu composite coating with multilayer structure was prepared by electrodeposition. The microstructure of the composite coating was analyzed by SEM and XRD. The microhardness and friction characteristics of the coating were tested, and the differences in the microstructures and properties of different coating structures were analyzed. Microstructure coatings with two layers (Cu + TiB2/Cu) and three layers (Cu + TiB2/Cu + Cu) were prepared on the copper substrate by electrodeposition. The TiB2 particles reduced the deposition rate of the TiB2/Cu composite coating by electrodeposition, by up to 29%. The TiB2 particles in the electrolyte increased the discharge voltage of the electrodeposition process. The content of TiB2 affected the microhardness, friction, and wear properties of the TiB2/Cu composite coating. The TiB2 particles increased the microhardness of the TiB2/Cu composite coating by 61%. The multilayer-structured coating prepared by electrodeposition could control the overall properties of the coating. The microhardness and friction coefficient of the TiB2/Cu + Cu coating were between those of the Cu and TiB2/Cu composite coatings. [ABSTRACT FROM AUTHOR]

Despite remarkable advances in the diagnosis of invasive fungal infections (IFIs), rapid, specific, sensitive, and cost-effective detection methods remain elusive. Due to their stability, ease of production, and specificity to signature molecules of fungal pathogens, short single-stranded sequences of DNA, RNA, and XNA, collectively called aptamers, have emerged as promising diagnostic markers. In this perspective, we summarize recent progress in aptamer-based diagnostic tools for IFIs and discuss how these tools could potentially meet the needs and provide economical and simple solutions for point-of-care for better management of IFIs. [ABSTRACT FROM AUTHOR]

All-solid-state lithium–sulfur batteries are considered one of the most promising candidates for energy storage devices due to their high energy density and safety. However, the poor electron transport of sulfur-based cathodes significantly reduces their reaction kinetics, resulting in low utilization efficiency and subpar rate performance. Herein, leveraging the similar chemical properties of sulfur and selenium, we uniformly deposit SexS1−x (x = 0–0.3) solid solutions with different selenium content on the surface of active carbon via a facile melt-diffusion method to achieve SexS1−x@AC (x = 0–0.3) composite materials. The introduction of selenium effectively enhances the lithium-ion diffusion coefficient of the SexS1−x@AC (x = 0–0.3) cathodes, and improves the stability of the cathode/solid electrolyte interface. With the increase in selenium content, the reaction kinetics of the SexS1−x@AC (x = 0–0.3) cathodes are altered. Specifically, the average lithium-ion diffusion coefficients for the S@AC and Se0.2S0.8@AC cathodes are 6.11 × 10−14 and 1.65 × 10−13 cm2 s−1, respectively, showing a twofold increase. Concurrently, the Se0.2S0.8@AC cathode exhibits higher discharge capacity (698.8 mA h g−1) than that of the S@AC cathode (501.3 mA h g−1) at 1 A g−1. Surprisingly, even when the mass loading increases to 8.85 mg cm−2, the Se0.2S0.8@AC cathode still shows superior cycling stability, which is attributed to the fast ionic/electronic transport pathways within the cathode. Moreover, the Se0.2S0.8@AC cathode maintains good physical contact at the cathode/SE interface after cycling. In all-solid-state lithium–sulfur batteries, the introduction of selenium in the sulfur cathode enhances reaction kinetics (1.65 × 10−13 cm2 s−1), provides additional reactive sites, and significantly improves the electrochemical performance of Se0.2S0.8@AC even with high mass loading (8.85 mg cm−2). [ABSTRACT FROM AUTHOR]

Streptococcus pneumoniae is the major cause of invasive pneumococcal disease. However, the global population structure remains largely unexplored. In this study, we investigated the spatial and temporal patterns of genetic variation of S. pneumoniae based on archived multilocus sequence typing data from PubMLST.org. Our analyses demonstrated both shared and unique distributions of sequence types (STs) and allele types among regional populations. Among the 17 915 global STs, 36 representing 15 263 isolates were broadly shared among all six continents, consistent with recent clonal dispersal and expansion of this pathogen. The analysis of molecular variance revealed that >96% genetic variations were found within individual regional populations. However, though low (<4%), statistically significant genetic differentiation among regional populations was observed. Comparisons between non-clone-corrected and clone-corrected datasets showed that localized clonal expansion contributed significantly to the observed genetic differentiations among regions. Temporal analyses of the isolates showed that implementation of pneumococcal conjugate vaccine impacted the distributions of STs, but the effect on population structure was relatively limited. Linkage disequilibrium analyses identified evidence for recombination in all continental populations; however, the inferred recombination was not random. We discussed the limitations and implications of our analyses to the global epidemiology and future vaccine developments for S. pneumoniae. [ABSTRACT FROM AUTHOR]