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Grid-connected offshore wind farms are likely to cause harmonic resonances in the power system that jeopardize the safe operation of the power grid. To this end， the impact of grid-connected offshore wind farms on the transient overvoltage and harmonic resonance characteristics of the onshore power grid PCC （point of common coupling） is studied， and a harmonic resonance management scheme is proposed. Firstly， PSCAD simulation modeling is performed for a grid-connected project of offshore wind farms in Zhejiang Province. Then the transient overvoltage and harmonic resonance characteristics of the grid-connected system under different operation modes are obtained by simulation. The results show that the maximum per-unit value of PCC transient overvoltage is 2.1 p.u.， which is less than the limit value of 3.0 p.u. and meets the safety requirements. Finally， the harmonic suppression strategy of parallel connection with low impedance branch filters five times and seven times respectively at PCC that significantly weakens the harmonic amplification of PCC and reduces the total harmonic distortion rate to less than 1.5%， eliminating the second to seventh low-frequency harmonic amplification.

This paper centers on the core business application—the automatic topology identification in transformer areas—of distribution IoT with new energy as its mainstay. It proposes an automatic topology identification technology testing scheme that considers identification reliability， high identification accuracy， and anti-disturbance capability. Besides， a unique “edge-to-end” interaction test platform for the distribution IoT area is developed. Afterward， the functions and performance of the mainstream technical schemes of Zhejiang Electric Power Co.， Ltd. are evaluated in all aspects. The “active current injection plus frequency-domain signal detection” is selected as the optimal technical scheme for topology identification. The topology identification technology testing and research can lay the application foundation for the subsequent interconnection， intercommunication， and interoperability of the distribution IoT and the transformation of the distribution networks.

In order to solve the issue of low efficiency in retired battery clustering, a method for quickly obtaining a charging curve and Incremental Capacity (IC) curve based on Convolutional Neural Networks (CNN) is proposed. By training a CNN model, the method enables accurate prediction of complete IC curves and V-Q curves from local charging curves starting at any beginning. The prediction accuracy was validated using the Oxford battery degradation dataset, and transfer learning was conducted by fine-tuning the model trained on LCO batteries for use with LFP batteries, which reduced the RMSE of the estimation and validated the generalizability of the model. Peak parameters were extracted from both the original and predicted IC curves for clustering, and the t-test was applied to eliminate outliers, which significantly reduced the time required to obtain clustering features and improved clustering efficiency. [ABSTRACT FROM AUTHOR]

Excessive oxidative stress impairs cartilage matrix metabolism balance, significantly contributing to osteoarthritis (OA) development. Celastrol (CSL), a drug derived from Tripterygium wilfordii , has recognized applications in the treatment of cancer and immune system disorders, yet its antioxidative stress mechanisms in OA remain underexplored. This study aimed to substantiate CSL's chondroprotective effects and unravel its underlying mechanisms. We investigated CSL's impact on chondrocytes under both normal and inflammatory conditions. In vitro , CSL mitigated interleukin (IL)-1β-induced activation of proteinases and promoted cartilage extracellular matrix (ECM) synthesis. In vivo , intra-articular injection of CSL ameliorated cartilage degeneration and mitigated subchondral bone lesions in OA mice. Mechanistically, it was found that inhibiting nuclear factor erythroid 2-related factor 2 (NRF2) abrogated CSL-mediated antioxidative functions and exacerbated the progression of OA. This study is the first to elucidate the role of CSL in the treatment of OA through the activation of NRF2, offering a novel therapeutic avenue for arthritis therapy. [ABSTRACT FROM AUTHOR]

The ability to locate and quantify large strains will significantly improve the real‐world application scenario of flexible and stretchable strain sensors. However, current methods for implementing stretchable distributed strain sensing still face challenges such as complicated demodulation, multisensor crosstalk, and high power consumption. Herein, a self‐powered and stretchable optical fiber strain sensor is reported with distributed sensing capability based on mechanoluminescent optical fiber, where mechanoluminescent phosphors with different emission color light are discretely integrated onto the outer cladding of the elastomer optical fiber. Based on the wavelength coding technique and time‐domain filtering comparison method, the capability of strain magnitude quantification (10–60%) and strain location identification together in a single stretchable optical fiber is successfully realized, even at multiple positions simultaneously in the strain‐applied situation. Moreover, this stretchable optical fiber strain sensor shows insensitivity to bending, compression, and temperature disturbances and outstanding durability (>8000 cycles). Due to the excellent light confinement of the elastomer optical fiber, demonstrations such as bright‐field measurement, saline water operation, and wearable glove application exhibit its potential as a promising technology for future self‐powered distributed optical sensing systems. [ABSTRACT FROM AUTHOR]

In order to attain the pollution characteristics difference between composite rod insulators and standard disc-type suspended insulator which is critical to the insulation selection of transmission line, pollution accumulated on composite rod insulators and standard form suspended insulators suspended in the same tower near typical pollution sources in Zhejiang province were tested, including the equivalent salt deposit density (ESDD) and the non-soluble deposit density (NSDD). Also the factors caused the difference were analysed for the first time. It is shown that in Zhejiang area, the contamination on upper surface of composite insulators is more serious than that of standard form suspended insulators, and the situation is inverse on the lower surface; the entire shed value of ESDD and NSDD from composite insulator is 0.8, 1.27 times of the values from standard form suspended insulators, respectively. The contamination difference of upper surface and lower surface of the composite insulators is smaller than that of standard form suspended insulators. According to the analysis, the rainfall and PM10 concentration could notably effect the ESDD difference between composite insulators and standard form suspended insulators. With stronger rainfall and less PM10 concentration, the ESDD ration of composite insulators and standard form suspended insulators trend to be smaller.

Highly hydrophobic surface property is important for many applications, such as anticorrosion, antifogging, and antifouling. With regard to some practical applications, both mechanical endurance and thermal stability are essential. Here, we report a new method for making highly hydrophobic surfaces with simultaneously enhanced mechanical endurance and thermal stability. Such high-performance hydrophobic surfaces were prepared by coating electrospraying derived fluorinated SiO2 particles on various substrates, including glass slide, ceramic wafer, metal foil, and polymer sheet, with methyl silicone resin as the binder. Fluorinate silane was homogenously doped in the matrix of SiO2 particles, which can provide excellent protection effect. Meanwhile, the thermally stable methyl silicone resin can afford strong binding force between SiO2 particles and the substrates. Therefore, the hydrophobic surfaces created here possess both high mechanical endurance and excellent thermal stability. [ABSTRACT FROM AUTHOR]