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Aiming at the problems such as small target scale, complex background, difficult detection, false detection and leakage detection of aerial insulators in transmission lines, this paper proposes an insulator defect detection algorithm based on improved YOLOv5. Firstly, CBAM attention module is added to the backbone network of YOLOv5 to improve the feature extraction capability of insulator pictures. Secondly, in the feature extraction part, PANet structure is replaced by BiFPN structure to make full use of the underlying feature information. Finally, the improved K-means algorithm is used to determine the prior frame and improve the defect detection accuracy of the insulator. Experimental results show that this method can improve the identification accuracy of insulator defect detection in transmission lines.

The power transformer plays a key role in the power distribution and transmission of the power system of the equipment, if the transformer fault leads to unexpected outage of the power system, then it will have a great threat to the whole power system, through the analysis of the transformer fault text can better guide the procurement of the transformer and fault maintenance. This paper proposes a classification method of transformer fault text based on two feature channels. This method extracts useful text emotion information from different aspects and levels by using two feature vectors, namely word vector and pinyin vector, and inputs it into Bilstm network to extract local and global semantic features. Then the features are fused through the attention mechanism. Finally, the features output by softmax function are classified and predicted. Experimental results show that the proposed method greatly improves the accuracy of transformer fault text classification.

The densification process, microstructure evolution, and final optical quality of the transparent MgO⋅nAl2O3 (n = 1.1 and 1.5) ceramics pre-sintered in air and under vacuum were investigated for the effects of pre-sintering atmosphere. The samples pre-sintered in air exhibited uniform microstructure, which was easier to obtain high optical quality at lower HIP temperatures. However, non-cubic precipitates appeared in the samples with a high Al2O3/MgO ratio after HIP treatment, resulting in the deterioration of transmittance. For the samples pre-sintered under vacuum, a large-grain layer was formed on the sample surface due to accelerated MgO volatilization. However, non-cubic precipitates did not appear due to the generation of oxygen vacancies. The mechanisms of formation of the large-grain layer, non-cubic precipitates were discussed from the viewpoint of MgO vaporization, Al2O3/MgO molar ratio, and oxygen vacancy.

Breast cancer is a common malignant tumor in women. At present, the main treatment for breast cancer is radiotherapy. Due to the difference in radiosensitivity between individuals or tumor cells, the effect of radiotherapy is not good. Therefore, in radiotherapy, how to use various auxiliary means to reduce the radiation resistance of tumor, Therefore, it has become an important research topic to improve the radiosensitivity of the tumor. Fibroblast growth factor-1 (FGF1) plays an important role in tumor migration. Therefore, the study of miR-143-3p increasing the radiosensitivity of breast cancer cells through FGF1 is proposed in this paper. In this study, a control group experiment was set up to study. During the experiment, the relative expression of miR-143-3p was detected by fluorescent quantitative PCR of miRNA, and the cell irradiation experiment was created to analyze the radiosensitivity of breast cancer cells by comparing their survival fraction. The results of this study showed that when the radiation dose was 0, the survival scores of the three groups were all 1. The survival fraction of the experimental group decreased from 0.26 ± 0.045 to 0.068 ± 0.008 when the dose was added to 4Gy. The survival fraction of the experimental group was always greater than that of the two control groups. The results of this study show that miR-143-3p can increase the radiosensitivity of breast cancer cells through FGF1.

A smart manufacturing system (SMS) is a multi-field physical system with complex couplings among various components. Usually, designers in various fields can only design subsystems of an SMS based on the limited cognition of dynamics. Conducting SMS designs concurrently and developing a unified model to effectively imitate every interaction and behavior of manufacturing processes are challenging. As an emerging technology, digital twins can achieve semi-physical simulations to reduce the vast time and cost of physical commissioning/reconfiguration by the early detection of design errors/flaws of the SMS. However, the development of the digital twins concept in the SMS design remains vague. An innovative Function-Structure-Behavior-Control-Intelligence-Performance (FSBCIP) framework is proposed to review how digital twins technologies are integrated into and promote the SMS design based on a literature search in the Web of Science database. The definitions, frameworks, major design steps, new blueprint models, key enabling technologies, design cases, and research directions of digital twins-based SMS design are presented in this survey. It is expected that this survey will shed new light on urgent industrial concerns in developing new SMSs in the Industry 4.0 era.

Novel (Tb1-xLux)2O3 magneto-optical transparent ceramics were prepared through a solid-solution method via vacuum pre-sintering followed by hot isostatic pressing (HIP). The Lu-containing samples were solid-solution phases between Tb2O3 and Lu2O3, which effectively stabilized the phase transition of Tb2O3 during the sintering process. A typical component of (Tb1-xLux)2O3 ceramic with x = 0.5 was selected to study the densification behavior and microstructure evolution in detail. The polished (Tb0.5Lu0.5)2O3 ceramics with a thickness of 3 mm vacuum pre-sintered at 1700 °C under 1.0 × 10−3 Pa combined with HIP post-treatment at 1600 °C showed good magneto-optical property. The Verdet constant measured at 633 nm was -224.33 rad·T−1 m−1, 30% higher than that of Tb3Al5O12 (TAG). However, the in-line transmittance was 73.6% at 633 nm, lower than that of TAG. The (Tb1-xLux)2O3 ceramics will be a promising material for Faraday devices after further improving the optical quality.

Accelerating slow water dissociation kinetics is key to boosting the hydrogen evolution reaction (HER) in alkaline media. We report the synthesis of atomically dispersed MoO

A refractive index fiber probe has been proposed based on a long-tapered microfiber, which was obtained from a long single-mode microfiber by the oxyhydrogen-flame-scanning and stretching method using a multifunctional fiber tapering machine. This microfiber probe was used to detect the refractive index of seawater samples with different concentrations by demodulating the intensity of reflected light. The refractive index sensing performance of the long-tapered microfibers elaborated by the low refractive index UV glue distributing silver nanoparticles and silicon nanoparticles were experimentally demonstrated, compared and analyzed. More stable spectra and sensing performance was obtained for the silicon nanoparticles compared to that of silver nanoparticles. Although a high average refractive index sensitivity of 13.047 dBm R−1IU−1 was obtained for the long-tapered microfiber coated by two layers of silver nanoparticle UV films. However, the quality of the corresponding spectra was severely damaged, and the amplitude of light intensity at different wavelengths varied greatly. These problems can be well avoided for the silicon nanoparticle-decorated microfiber tapers, where the overall monotonic variation of the interference spectral intensity will greatly simplify the signal demodulation process and improve the reliability of the measurement results.

The high incidence of respiratory diseases has dramatically increased the medical burden under the COVID-19 pandemic in the year 2020. It is of considerable significance to utilize a new generation of information technology to improve the artificial intelligence level of respiratory disease diagnosis.Based on the semi-structured data of Chinese Electronic Medical Records (CEMRs) from the China Hospital Pharmacovigilance System, this paper proposed a bi-level artificial intelligence model for the risk classification of acute respiratory diseases. It includes two levels. The first level is a dedicated design of the "BiLSTM+Dilated Convolution+3D Attention+CRF" deep learning model that is used for Chinese Clinical Named Entity Recognition (CCNER) to extract valuable information from the unstructured data in the CEMRs. Incorporating the transfer learning and semi-supervised learning technique into the proposed deep learning model achieves higher accuracy and efficiency in the CCNER task than the popular "Bert+BiLSTM+CRF" approach. Combining the extracted entity data with other structured data in the CEMRs, the second level is a customized XGBoost to realize the risk classification of acute respiratory diseases.The empirical study shows that the proposed model could provide practical technical support for improving diagnostic accuracy.Our study provides a proof-of-concept for implementing a hybrid artificial intelligence-based system as a tool to aid clinicians in tackling CEMR data and enhancing the diagnostic evaluation under diagnostic uncertainty.

Ni3S2 has attracted great interest as a potential alternative catalyst for the oxygen evolution reaction; however, the formation of sulfur–hydrogen bonds on Ni3S2 suppressed the hydrogen evolution ...

Ruthenium (Ru)-based materials have been proven to be highly efficient hydrogen evolution reaction (HER) electrocatalysts and have become the most promising candidates for replacing platinum (Pt)-based electrocatalysts. Herein, we report an easily scalable electrospinning strategy to construct nitrogen-doped carbon nanofibers with porous hierarchical structures and uniformly dispersed Ru nanoparticles (abbreviated as ES-Ru-ZIF-900). Benefiting from the porous fibrous nanoarchitecture caused by the pyrolysis of the zeolitic imidazolate framework-8, the abundant firmly immobilized Ru NPs, and the high conductivity of the N-doped carbon matrix, the resultant ES-Ru-ZIF-900 electrocatalyst exhibits an extraordinary HER performance. ES-Ru-ZIF-900 only needs an overpotential of 21 mV to drive the current density of 10 mA cm−2, and possesses long durability for over 14 h in 1.0 M KOH, superior to Pt/C and most of the non-Pt based electrocatalysts. This work offers a universal and efficient synthetic strategy for preparing metal-based nitrogen-doped carbon hybrid catalysts with enhanced HER activity.

Ru, RuO2 and MoO3 embedded carbon nanorods (Ru-RuO2/MoO3 CNRs) were synthesized through electrospinning and low-temperature calcination. Results of comprehensive characterizations suggest that the strong interaction between Ru and Mo species, large electrochemical surface area, and high electrical conductivity (a proper ratio of RuO2 to Ru) endow Ru-RuO2/MoO3 CNRs-350 with excellent hydrogen evolution reaction (HER) performance.

Phase transformation process of magneto-optical material Tb 2 O 3 at elevated temperature has been investigated in different atmosphere. When heating in air, Tb 2 O 3 is firstly oxidized to TbO 1.81 at 500 °C. Finally, TbO 1.81 is respectively deoxidized to TbO 1.714 at 600 °C and Tb 2 O 3 at 988 °C. It is remarkable that the most stable phase at room temperature is not Tb 2 O 3 , but TbO 1.81 . While sintering in vacuum, the reversible phase transition of Tb 2 O 3 above 1600 °C makes Tb 2 O 3 crack from inside to outside. These findings provide a deep understanding of controlling and avoiding the phase transformations of Tb 2 O 3 , which has great guiding significance to preparing Tb 2 O 3 materials.

Large-scale personalization is becoming a reality. To ensure market competitiveness and economic benefits, enterprises require rapid response capability and flexible manufacturing operations. However, variant design and production line reconfiguration are complicated because it involves the commissioning, replacement, and adaptive integration of equipment and remodification of control systems. Herein, a digital twin-driven production line variant design is presented. As a new technology, the digital twin can realize the parallel control from the physical world to the digital world and accelerate the design process of the production line through a virtual–real linkage. Simultaneously, the actual production line can be simulated to verify the rationality of the design scheme and avoid cost wastage. Four key technologies are described in detail, and a production line variant design platform based on digital twin is built to support rapid production line variant design. Finally, experiments using a smartphone assembly line as an example are performed; the results demonstrate that the proposed method can realize production line variant design and increase production efficiency.

Ruthenium (Ru) as a cheaper alternative to Pt has been studied as a viable alternative for the hydrogen evolution reaction (HER) catalyst, however, no single-atom Ru catalyst has been reported for the HER electrocatalysis. Herein, we design and develop the first type of single-atom Ru based catalyst applied for the HER under pH-universal conditions. This binder-free catalyst consists of single Ru atoms anchored to the surface of MoS2 nanosheets array supported by a carbon cloth (Ru-MoS2/CC, Ru in Ru-MoS2: 0.37 wt%). The abundant dispersed single Ru atoms are highly catalytically active, and the MoS2 array supported 3D porous structure offers more opportunities for active sites and serves as co-catalysts for synergetic catalysis, with accompanying enhanced the electrical conductivity of this array-catalyst. Remarkably, the Ru-MoS2/CC exhibits extremely enhanced catalytic activity compared to that of MoS2/CC and possesses good long-term stability. Density functional theory calculations revealed that the improved catalytic activities stem from the synergistic effect between MoS2 and single-atom Ru. This discovery holds a great potential to accelerate the large-scale binder-free application of single Ru atoms in industry.

Herein, Ni17W3 nanoparticles (NPs) decorated WO2 nanohybrid supported by Ni foam (Ni17W3/WO2/NF) is successfully prepared via annealing Ni4W6O21(OH)2·4H2O/NF under reductive atmosphere and applied ...

Virtual power plant (VPP) composed of a large number of distributed energy resources (DERs) has become a regional multienergy aggregation model to realize the large-scale integration of renewable energy generation into the grid. Due to the characteristics of centralized management, the existing energy operation mode is difficult to simply apply to distributed energy resources transactions. The decentralization, transparency, contract execution automation and traceability of blockchain technology provide a new solution to the aggregation of decentralized resources and the opacity of transactions in VPP. In this paper, the existing problems of virtual power plants are analyzed, and the virtual power plant trading model is designed, which realizes the transparent benefit distribution and message transmission of virtual power plants. The virtual power plant blockchain network based on blockchain technology in this model solves the DERs coordination problem in VPP and the security and efficiency problems in information transmission. Combined with the actual situation of virtual power plant, the blockchain network collaboration mechanism (BNCM), which is convenient to reach agreement, is designed. Compared with the traditional practical Byzantine fault tolerance (PBFT) consensus algorithm, this mechanism can make DERs reach a consensus quickly. Finally, simulation experiments on the consensus algorithm show that the algorithm can reduce the collaboration time between DERs under the premise of ensuring the same fault tolerance rate and is more suitable for VPP scenarios with a large number of DERs.

Ni

Ru, RuO2 and MoO3 embedded carbon nanorods (Ru-RuO2/MoO3 CNRs) were synthesized through electrospinning and low-temperature calcination. Results of comprehensive characterizations suggest that the strong interaction between Ru and Mo species, large electrochemical surface area, and high electrical conductivity (a proper ratio of RuO2 to Ru) endow Ru-RuO2/MoO3 CNRs-350 with excellent hydrogen evolution reaction (HER) performance.

With the integration of distributed generation and the construction of cross-regional long-distance power grids, power systems become larger and more complex. They require faster computing speed and better scalability for power flow calculations to support unit dispatch. Based on the analysis of a variety of parallelization methods, this paper deploys the large-scale power flow calculation task on a cloud computing platform using resilient distributed datasets (RDDs). It optimizes a directed acyclic graph that is stored in the RDDs to solve the low performance problem of the MapReduce model. This paper constructs and simulates a power flow calculation on a large-scale power system based on standard IEEE test data. Experiments are conducted on Spark cluster which is deployed as a cloud computing platform. They show that the advantages of this method are not obvious at small scale, but the performance is superior to the stand-alone model and the MapReduce model for large-scale calculations. In addition, running time will be reduced when adding cluster nodes. Although not tested under practical conditions, this paper provides a new way of thinking about parallel power flow calculations in large-scale power systems.

Here, we describe the synthesis of a novel interwoven NiS/NiS2 structure with an amorphous interface accomplished by carrying out a one-step thermal decomposition of nickel sulfate and thiourea. A partial phase transition from NiS2 to NiS induced the amorphous interface in NiS/NiS2 and was expected to separate the H* and H− intermediates onto different interface sites, and to reduce the interfacial energy and charge-transfer resistance as well. When NiS/NiS2 was applied as an electrocatalyst for overall water splitting (OWS), it achieved a geometrical current density of 100 mA cm−2 at a low overpotential of 248 mV for the hydrogen evolution reaction (HER) and 416 mV for the oxygen evolution reaction (OER), obviously superior to those of the single-phase catalysts. In addition, it was also employed as an efficient bifunctional catalyst for OWS, yielding a current density of 10 mA cm−2 at a voltage of 1.62 V.

The major challenges encountered in the search for the replacement of Pt group materials toward the hydrogen evolution reaction (HER) in alkaline electrolytes are the stabilities and sluggish kinetics of non-noble metal electrocatalysts. MoNi has exhibited considerably higher catalytic activity than MoNi2, MoNi3 and MoNi4 in alkaline electrolytes; however, there are no reports on the application of MoNi to the HER. Herein, we report for the first time the construction of MoNi nanoparticle decorated CoMoO3 cuboid arrays of vertical growth using Ni foam as the scaffold (MoNi/CoMoO3/NF). Owing to the high catalytic activity of MoNi nanoparticles, the interaction between different phases, the ability to increase the active sites of CoMoO3 cuboids and the synergistic effect on the whole, the MoNi/CoMoO3/NF exhibits high stability and activity with zero onset overpotential and a low Tafel slope of 35 mV dec−1, and only 18 mV is needed to afford 10 mA cm−2 in 1 M KOH, which is even better than that of the state-of-the-art Pt/C catalyst. Density functional theory calculations demonstrate that the CoMoO3 and MoNi in MoNi/CoMoO3 synergistically enhanced water splitting activity. Our findings provided a new idea to integrally construct non-noble metal catalysts with outstanding HER performance surpassing that of noble metals.

In a previous study, we reported the positive effects of extremely low frequency electromagnetic field (ELF-MF) exposure on Alzheimer's disease (AD) rats; however, the underlying mechanism remains unclear. In addition, we found that Raf-1 kinase inhibitor protein (RKIP) was downregulated by microwave exposure in the rat hippocampus. Our hypothesis was that RKIP-mediated NF-κB pathway signaling is involved in the effect of ELF-MF on the AD rat. In this study, D-galactose intraperitoneal (50 mg/kg/d for 42 d) and Aβ25-35 hippocampal (5 μL/unilateral, bilateral, single-dose) injection were implemented to establish an AD rat model. Animals were exposed to 50 Hz and 400 µT ELF-MF for 60 continuous days. The spatial memory ability of the rat was then tested using the Morris water maze. Protein expression and interaction were detected by western blotting and co-immunoprecipitation for RKIP-mediated NF-κB pathway factors. The results showed that ELF-MF exposure partially improved the cognitive disorder, upregulated the levels of RKIP, TAK1, and the RKIP/TAK1 interaction, but downregulated p-IKK levels in AD rats. These results indicated that RKIP-mediated NF-κB pathway signaling plays an important role in the ELF-MF exposure-mediated improvements in the AD rat. Our study suggested that ELF-MF exposure might have a potential therapeutic value for AD. Further in depth studies are required in the future.

N-(Aminobutyl)-N-(ethylisoluminol) (ABEI)-functionalized gold nanoparticles (AuNPs) on cobalt disulfide nanowires (ABEI/AuNPs/CoS2 NWs) are rapidly synthesized through a microwave-assisted reduction of chloroauric acid (HAuCl4) on CoS2 NWs with ABEI. The obtained nanohybrids with enhanced chemiluminescence are exploited for the non-enzymatic detection of H2O2.

A TiO2/SiOx/Si composite derived from cellulosic cotton as the structural template was biomimetically synthesized. Modified sol–gel deposition processes were performed to coat each cellulose nanofiber with a SiO2 thin gel layer, followed by layer-by-layer self-assembly processes to form an external TiO2 coating with controllable thickness. The resulted matter was calcined in air to obtain the TiO2/SiO2 composite, which was successively put in N2 atmosphere and treated with magnesiothermic reduction reaction, resulting in the final TiO2/SiOx/Si composite. The composite possessed a typical hierarchical three-dimensional (3D) nanotubular network microstructure precisely inherited from the cellulosic cotton template, and each nanotube had a core-shell nanostructure with Si-based matters as the core and TiO2 coating as the shell. Compared with the bare nanotubular SiOx/Si material, the TiO2/SiOx/Si composite showed a highly enhanced electrochemical performance as an anode material for lithium-ion batteries (LIBs), delivering an initial discharge capacity of 2370 mAh g−1 at a current density of 0.2 A g−1 (an initial Coulombic efficiency of 56.4%), a reversible capacity of 682 mAh g−1 after 100 discharge/charge cycles, and a discharge capacity of 241 mAh g−1 at a high current density of 2.0 A g−1. The excellent specific capacity, cycling stability and rate capability are ascribed to the synergistic effect of the unique 3D porous nanotubular network structure and the uniform TiO2 coating layer, which accommodates the volume variation of Si-based components during cycling, offers sufficient ion transport pathways and improves the electron transfer efficiency. This work provides a facile biomass-based strategy for fabrication of metal oxide/Si composites with well-defined microstructures that exhibit significant potential as anode materials for LIBs.

Transition metal oxides (TMOs) and their heterostructure hybrids have emerged as promising candidates for hydrogen evolution reaction (HER) electrocatalysts based on the recent technological breakthroughs and significant advances. Herein, Ru-Co oxides/Co3 O4 double-shelled hollow polyhedrons (RCO/Co3 O4 -350 DSHPs) with Ru-Co oxides as an outer shell and Co3 O4 as an inner shell by pyrolysis of core-shelled structured RuCo(OH)x @zeolitic-imidazolate-framework-67 derivate at 350 °C are constructed. The unique double-shelled hollow structure provides the large active surface area with rich exposure spaces for the penetration/diffusion of active species and the heterogeneous interface in Ru-Co oxides benefits the electron transfer, simultaneously accelerating the surface electrochemical reactions during HER process. The theory computation further indicates that the existence of heterointerface in RCO/Co3 O4 -350 DSHPs optimize the electronic configuration and further weaken the energy barrier in the HER process, promoting the catalytic activity. As a result, the obtained RCO/Co3 O4 -350 DSHPs exhibit outstanding HER performance with a low overpotential of 21 mV at 10 mA cm-2 , small Tafel slope of 67 mV dec-1 , and robust stability in 1.0 m KOH. This strategy opens new avenues for designing TMOs with the special structure in electrochemical applications.

Self-reconstruction of oxygen evolution reaction (OER) catalyst, especially metal (oxy)hydroxides or oxides, has attracted much attention. Herein, an in-situ self-reconstruction process for Ni, Fe, Zn ternary-metal hydroxides (NFZ-TH) involving significant morphology transformation, and self-modulated electronic structure change of Ni and Fe owing to the etching of Zn species under anodic polarization potential is revealed. NFZ-TH derived materials, undergoing in-situ self-reconstruction (NFZ-TH-SR), exhibits superior OER performance (η = 217 mV @j = 10 mA cm−2geometry) and excellent stability over a period of ~48 h. Nano-pitted surface resulting from etching of Zn species improves the electrochemical surface area. Meanwhile, in NFZ-TH-SR, large amounts of defects induced defect-/corner-sited Fe and adjustability of NiOOH species are verified by Mossbauer spectra and in-situ Raman spectra respectively. Density functional theory calculations give insight that both defect-/corner- sited Fe and Ni at next-nearest-neighbour defect-site have high activity. This paper helps understand that the proposed in-situ self-reconstruction strategy can improve the electrochemical performance of OER catalysts.

The combinations of Earth-abundant materials with noble metals provide an orientation for developing highly active and stable catalysts toward hydrogen production with reduced noble metal loadings. Here, we designed carbon cloth (CC)-supported Earth-abundant Co(OH)2 nanosheets array (Co(OH)2/CC) as an ideal three-dimensional (3D) substrate for Pt electrodeposition (Pt–Co(OH)2/CC, Pt in Pt–Co(OH)2: 5.7 wt %) to achieve top performance of a hydrogen evolution reaction (HER) under alkaline and neutral conditions. The Pt–Co(OH)2/CC catalyst exhibits a near-zero onset overpotential and a Tafel slope of 70 mV dec–1, and it requires an overpotential of 32, 54, and 122 mV to deliver the geometrical current density of 10, 20, and 100 mA cm–2, respectively, with catalytic activities exceeding to those of the commercial Pt/C decorated CC (Pt/C/CC). Furthermore, the HER activity of Co(OH)2 decorated with several transition metals (Ni, Co, and Fe) was demonstrated in experiments, further validating the high HER activi...

The densification and mechanical properties of B4C–TiB2 composites fabricated by reactive pulsed electric current sintering from a mixture of TiC and amorphous B powders were investigated. The excess of B was essential to remove the carbon produced by the reaction. The degassing process at 1900 °C before applying a 50 MPa external pressure greatly improved the densification of the composites. The B4C–41 vol% TiB2 composite obtained at the optimum condition had a high 3-point bending strength of 891 MPa, a Vickers hardness of 28 GPa and a fracture toughness of 4.4 MPa m1/2, respectively.