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The damage impact of mechanical shocks on stator bar insulation is a key factor in high-voltage motor accidents. This study conducted electrical aging acceleration and breakdown experiments on damaged stator insulating materials to understand failure causes and evaluation methods. The relationship between sample defect area and depth and electrical properties was analyzed, along with the morphology of the damaged surface using a scanning electron microscope. Results show that the defect area correlates with impact mode but does not directly impact electrical performance. Effective insulation thickness is positively linked to electrical performance. This study serves as a valuable reference for evaluating mechanical impact faults in high-voltage motors. [ABSTRACT FROM AUTHOR]

Hyperspectral imaging poses great challenges to traditional camouflage materials, primarily because there is a huge difference between the reflectance spectra of camouflage materials and natural plants in the 1400–2000 nm band. The difficulty of simulating the natural plant spectrum lies in reproducing the absorption peak of water by increasing the water content in a camouflage material. Herein, a mesoporous (MS) material is used to simulate the plant spectrum because such material can absorb and retain a large amount of water. MS was prepared via a two‐step method using tetraethyl orthosilicate and tetrabutyl titanate. The characteristics of the as‐prepared MS were examined via X‐ray diffraction, transmission electron microscopy, ultraviolet–visible diffusion reflectance spectroscopy and nitrogen adsorption–desorption isotherms. In addition, a film was prepared using the fully absorbent mesoporous material, and the water content was determined via near‐infrared spectroscopy and thermogravimetric analysis. The bonding between the mesoporous material and resin was examined via field emission gun scanning electron microscopy. The mechanical properties of the film were measured by a pendulum hardness tester and a cylindrical bending tester. The results indicate that low‐temperature synthesis followed by high‐temperature hydrothermal treatment is conducive to expanding the mesopore aperture, reaching a maximum of 23 nm. Moreover, the regular structure of the as‐prepared titanium‐containing mesoporous material is maintained under high hydrothermal temperature. The mesoporous film exhibits a good water absorption capacity of up to 80% by mass and can effectively simulate the spectrum of plants. The mechanical properties of the film are good, and the hardness of the film is related to the content of mesoporous powder. © 2023 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

In this study, an environment-friendly layered double hydroxide (LDH) film has been deposited on MgCa alloy by a two-step technique. To improve the chemical conversion technique and control the film properties, batch studies have been carried out to address various process parameters such as pH value, treatment temperature and immersion time. The chemical composition was determined by X-ray diffractometry and energy dispersive X-ray spectroscopy. The morphology was characterized by scanning electron microscopy. The corrosion resistance of the samples with various films was compared by polarization curves and immersion test. It is found that the transformation duration of Mg–Fe LDH is long. Too high pH value and temperature has harmful effect on the purity of the film composition. The corrosion resistance of the films formed at low value of pH or high temperature or short treatment time is deteriorative. The optimum process is as follows: the sample is first immersed in the solution containing Fe3+/HCO 3 −/CO 3 2− with a pH value of 5 at a temperature of 55 °C for 1 h to form a precursor film, and then this precursor film is immersed into the solution containing Fe3+/HCO 3 −/CO 3 2− with a pH of 11 at 55 °C for 24 h to obtain the Mg–Fe LDH conversion film. [ABSTRACT FROM AUTHOR]

The advantage of using composite electrode materials for energy storage is, to a large extent, the synergistic role of their components. Our work focuses on the investigation of the interactions of each phase, exploring the patterns found with the change of materials to provide theoretical or experimental foundations for future study. Here, conductive polymers (CPs), including polyaniline (PANi), polypyrrole (PPy), and polythiophene (PTh), as well as reduced graphene oxide (rGO), and TiO2 with the different crystalline phases of anatase and rutile were applied to form a series of free‐standing and flexible binary or ternary composite electrodes. The electrochemical behaviors of these composite electrodes are presented. The results indicate that the synergistic improvement in electrochemical performance is due to the incorporation of the different components. CPs significantly increase the current density of these composite films and contribute their pseudocapacitance to improve the specific capacitance, but lead to a decline in cycle stability. After introducing TiO2, both the specific capacitance and the cycle‐stability of rGO‐TiO2‐CP were synergistically improved. A CP can magnify the pseudocapacitance behavior of any of the TiO2 crystalline phases, and interactions vary with the specific CP and the specific TiO2 crystalline phase employed. The synergistic effects of the as‐prepared composites were theoretically predicted and explored. [ABSTRACT FROM AUTHOR]