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In the face of global climate change and the need for energy diversification, electrocatalytic technology emerges as an eco‐friendly solution. However, persistent electrode failures hinder long‐term stability. This review comprehensively outlines the primary causes leading to the failure of self‐supported electrodes, encompassing substrate passivation, substrate/catalyst dissolution, CO poisoning, catalyst migration and agglomeration, as well as cathodic etching. Proposed strategies center on material design, emphasizing anchoring, lattice matching, substrate stability, and morphological control. Advanced characterization techniques and in situ technologies offer promising ways. The integrated deployment of these strategies will provide crucial guidance and support for the sustainable advancement of electrocatalytic technology. [ABSTRACT FROM AUTHOR]

The electrocatalytic selective oxidation of 5‐hydroxymethylfurfural (HMF) presents a highly efficient and eco‐friendly method for biomass utilization. Herein, we synthesized pure β‐Ni(OH)2 and amorphous Ni(OH)2 on nickel foam (NF) using a facile stepwise electrodeposition technique and evaluated their catalytic performances for the oxidation of HMF to 2,5‐furan dicarboxylic acid (FDCA). The β‐Ni(OH)2 nanosheets‐decorated electrode (β‐NiNS/NF) exhibited excellent interfacial lattice matching with the substrate nickel, resulting in enhanced electron transfer at the catalyst‐substrate interface, as confirmed by electrochemical analysis. Consequently, the β‐NiNS/NF electrode displayed improved intrinsic electrocatalytic activity and interfacial stability. Additionally, it demonstrated effective HMF adsorption capability. These advantageous properties led to enhanced HMF conversion, selectivity, and structural stability. Notably, the β‐NiNS/NF electrode achieved an unprecedented FDCA yield of 80.6 % under relatively large current density galvanostatic electrolysis commonly used in industry. Moreover, our investigation identified a novel possible oxidation pathway during HMF electrocatalysis. This study not only showcases an efficient and scalable synthetic approach but also highlights the potential of the β‐NiNS/NF electrode for industrial HMF electrocatalytic oxidation under conditions involving relatively large applied currents. [ABSTRACT FROM AUTHOR]

The high temperature deformation behaviors of low-carbon steel QD08 were investigated by hot compression tests over temperatures from 1000°C to 1200°C and strain rates from 0.1 to 10 s −1 . In order to describe the flow characteristics, a constitutive equation was developed and the relation between the flow stress and Zener–Hollomon parameter was successfully analyzed via the hyperbolic sine function under the whole range of deformation condition. It can be found that the critical strain ε c increases with parameter Z increasing; the critical conditions for onset of dynamic recrystallization is ε > ε c = 61 . 9381 Z 0 . 1033 . Based on dynamic material model and Prasad’s instability criterion, the power dissipation map and the instability map were developed. The results show that the security domain of hot deformation for low-carbon steel QD08 at the temperature range between 1070°C and 1100°C, and strain rate range of around 5–10 s −1 , with a higher power dissipation factor, maintains a smooth variation, under stable deformation conditions. On the basis of processing map, the optimal deformation processing parameters are the hot deformation temperature range from 1070°C to 1100°C, and strain rate range from 5 to 10 s −1 .

Spindles are among the key parts of rotatory machinery and featured widely in a variety of industrial equipment. Fracture failure of a spindle (caused either by inappropriate design or operation) could lead to significant economic losses or high numbers of casualties. Using data from accidents, caused by spindle fracture in centrifuges in China as an example, this research work systematically investigates the reasons leading to the fracture failure of the spindles in operation. Our methods include analysing the chemical composition, micro-morphology, and mechanical properties of the fractures. Our results show that the spindle failure is due to a form of fatigue fracturing caused by stress concentration and alternative bending stress. A finite element method was additionally utilised to further calculate and analyse the stress distribution over a spindle. It was discovered that the stress is severely concentrated at the transition fillet of the spindle. Finally, we show that the stress distribution in the spindle can be improved by adopting a structure in the form of a conic section and by reducing the eccentric moment. In this way, the fatigue resistance of a spindle can be enhanced. [ABSTRACT FROM AUTHOR]

Due to various errors such as the radial distortion of lenses and perspective distortion in digital images, there are non-linear geometric distortions in such images. Therefore, a new method based on the black-white square array is proposed to calibrate visual measuring systems at a micro-sized measurement scale. Meanwhile, by analysing the sources of error, the binary cubic polynomial model for a curved error surface is established. Thereafter, the sub-pixel coordinates of each edge of the checkerboard calibration board are extracted to obtain the coordinates of corner points, which are regarded as the actual point coordinates. Later, the actual point coordinates are combined with the theoretical point coordinates to establish equations, so as to find the coefficients of the error model through fitting. On this basis, calibration is performed on the backlight visual measuring system at a micro-sized measurement scale. As verified experimentally, the proposed method is endowed with high measurement accuracy and robustness. Meanwhile, characterised by its simple and reliable calibration process, it has been applied in a system used for detecting the aperture and centre distance of the intermediate features in gear pumps. [ABSTRACT FROM AUTHOR]