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As the demand for power supply increases, the investment in the power transmission system constantly increases. An accurate economic evaluation of the power transmission system is essential for future investment decisions and management. Applying a single method in economic evaluation leads to excessive subjective consciousness and unreasonable weight allocation. The Euclidean distance in the traditional TOPSIS method only partially works on the condition that the criteria are linearly correlated. To solve these problems, an economic evaluation method based on improved TOPSIS and BWM-anti-entropy weight is proposed. For the assignment of weights, the method retains the advantages of subjective and objective weighting methods based on the Nash equilibrium, breaks through the limitation of utilizing a single method, which contributes to one-sided results, and enhances the scientific rigor and rationality of the comprehensive weighting process. Furthermore, based on comprehensive weights, the method improves the TOPSIS by introducing the Mahalanobis distance and Pearson correlation coefficients, which can eliminate the influence of linear correlation. Finally, ten 500 kV transmission and transformation projects are analyzed and ranked to verify the method's feasibility. Empirical analysis shows that the method can effectively evaluate the economic benefits of the power transmission system. [ABSTRACT FROM AUTHOR]

Most self-healing hydrogels always exhibited poor mechanical property which largely limited the applications in many fields. In this work, g-C3N4 nanosheets were introduced to the PVA-borax hydrogel to reinforce the network without sacrificing the self-healing ability. The obtained hydrogel displayed remarkable tensile strength (0.98 MPa), Young's modulus (1.54 MPa) and toughness (4.43 MJ m−3), of which the self-healing efficiency reached to 99 % in 10 min at room temperature. Overall, the strategy proposed in this work provides a simple, operatable and moderate approach to hydrogel with both excellent mechanical property and self-healing ability. [ABSTRACT FROM AUTHOR]

Herein, the microstructure stability of a newly developed hot‐working die (HWD700) steel at elevated temperatures up to 700 °C is investigated using transmission electron microscopy (TEM), selected‐area electron diffraction, energy‐dispersive spectrometer, and high‐resolution transmission electron microscope. The results show that the HWD700 steel exhibits a higher thermal stability than the commercial H13 steel when the temperature is up to 700 °C. After quenching and tempering, high densities of intra‐lath rodlike and inter‐lath spherical MC nano‐carbides and inter‐lath strip‐like M7C3 nano‐carbides are observed in the HWD700 steel. These carbides remain nanoscale at temperatures up to 700 °C. For comparison, rod‐shaped MC nano‐carbides in the tempered H13 steel tend to coarsen and transform into larger M23C6 carbides at temperatures up to 650 °C. The TEM observation further reveals that the interface misfit between the MC nano‐carbide and matrix in the HWD700 steel is as low as 0.88%, lower than that of 14.8% in the H13 steel. This can be the main reason for the improved stability of the HWD700 steel by pinning dislocations and grain boundaries and thereby hindering the recrystallization process at an elevated temperature. [ABSTRACT FROM AUTHOR]