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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 .

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]

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]

Abstract: Lead zirconate titanate (PZT) based piezoelectric composites embedded with ZnO nanowhiskers (ZnOw) were investigated to clarify the optimal sintering condition for densification, microstructure, and electrical properties. The samples are characterized by X-ray diffraction analysis and scanning electron microscopy. The results show that the increase of the sintering temperature and time is quite effective in improving the densification and piezoelectric properties of the PZT/ZnOw composites. However, the relative density and piezoelectric properties deteriorate as the composites are sintered over the optimal sintering condition. Particularly, the PZT/ZnOw composites sintered at 1150°C for 2h show excellent electrical properties of piezoelectric constant d 33 ∼471pC/N, relative dielectric constant ɛ ∼3838, planar electromechanical coupling factor k p ∼0.543, remnant polarization P r ∼23.2μC/cm2 and coercive field E c ∼9.2kV/cm. [Copyright &y& Elsevier]

Abstract: ZnO whiskers and Sb2O3 co-modified lead zirconate titanate (denoted as PZT/ZnO w /Sb2O3) piezoelectric composites were fabricated using a solid state sintering technique. The characteristic diffraction peaks of the PZT perovskite and ZnO phases were identified from all the composites, suggesting the retention of these individual phases. The grain size of PZT was found to be reduced with Sb2O3 addition. A high relative density of 96.5%–99.1% was achieved in PZT co-doped with ZnO w and Sb2O3. Both the piezoelectric and mechanical properties of the PZT/ZnO w /Sb2O3 composites showed significant improvement over the monolithic PZT. The intrinsic effects of ZnO w and Sb2O3 on the electrical and mechanical properties of the PZT/ZnO w /Sb2O3 composites were discussed. [Copyright &y& Elsevier]

Purpose: To evaluate the diagnostic accuracy of ultrasonograph and fine-needle aspiration cytologic examination (USG-FNAC) in the staging of axillary lymph node metastasis in breast cancer patients., Methods: We conducted an electronic search of the literature addressing the performance of USG-FNAC in diagnosis of axillary lymph node metastasis in databases such as Pubmed, Medline, Embase, Ovid and Cochrane library. We introduced a series of diagnostic test indices to evaluate the performance of USG-FNAC by the random effect model (REM), including sensitivity, specificity, likelihood ratios, and diagnostic odds ratios and area under the curve (AUC)., Results: A total of 20 studies including 1371 cases and 1289 controls were identified. The pooled sensitivity was determined to be 0.66 (95% CI 0.64-0.69), specificity 0.98 (95% CI 0.98-0.99), positive likelihood ratio 22.7 (95% CI 15.0-34.49), negative likelihood ratio 0.32 (95% CI 0.25-0.41), diagnostic OR 84.2 (95% CI 53.3-133.0). Due to the marginal threshold effect found in some indices of diagnostic validity, we used a summary SROC curve to aggregate data, and obtained a symmetrical curve with an AUC of 0.942., Conclusion: The results of this meta-analysis indicated that the USG-FNAC techniques have acceptable diagnostic validity indices and can be used for early staging of axillary lymph node in breast cancer patients.

Purpose: Any association between the CYP1A1 Ile462Val polymorphism and endometrial cancer risk remains inconclusive. For a more precise estimate, we performed the present meta-analysis., Methods: PUBMED, OVID and EMBASE were searched for the studies which met inclusion criteria. Data in all eligible studies were evaluated and extracted by two authors independently. The meta-analysis estimated pooled odds ratio (OR) with 95% confidence interval (CI) for endometrial cancer risk attributable to the CYP1A1 Ile462Val polymorphism., Results: A total of 7 studies were included in this meta-analysis. The results indicated no association between endometrial cancer risk and the CYP1A1 Ile462Val polymorphism (for Val vs Ile allele model [OR 1.09, 95% CI 0.73-1.62]; for Val.Val vs Ile.Ile genotype model [OR 1.54, 95% CI 0.56-4.23]; for (Ile.Val + Val.Val) vs Ile.Ile genotype model [OR 1.08, 95% CI 0.71-1.63]; for Val.Val vs (Ile.Ile + Ile.Val) genotype model [OR 1.46, 95% CI 0.53-4.04])., Conclusions: This meta-analysis suggests that there is no association between endometrial cancer risk and the CYP1A1 Ile462Val polymorphism.