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This paper focuses on enhancing the performance of electrocatalytic CO2 reduction reaction (CO2RR) by improving the dispersion of cobalt phthalocyanine (CoPc), especially for the methanol formation with multi-walled carbon nanotubes (CNTs) as a support. The promising CNTs-supported CoPc hybrid was prepared based on ball milling technique, and the surface morphology was characterized by means of those methods such as scanning electron microscopy (SEM), Fourier transform infrared spectrometer (FT-IR) and X-ray photoelectron spectra (XPS). Then, the synergistic effect of CNTs and ball milling on CO2RR performance was analyzed by those methods of cyclic voltammetry (CV), linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), gas chromatography (GC), and proton nuclear magnetic resonance spectroscopy (1HNMR). Subsequently, the reduction mechanism of CO2 on ball-milled CoPc/CNTs was revealed based on the DFT calculations. The results showed that the electrocatalyst CoPc/CNTs hybrid prepared with sonication exhibited a conversion efficiency of CO2 above 60% at -1.0 V vs. RHE, accompanied by the Faradaic efficiencies of nearly 50% for CO and 10% for methanol, respectively. The addition of CNTs as the support improved the utilization efficiency of CoPc and reduced the transfer resistance of species and electrons. Then the ball-milling method further improved the dispersion of CoPc on CNTs, which resulted in the fact that the methanol efficiency was raised by 6% and partial current density was increased by nearly 433%. The better dispersion of CoPc on CNTs adjusted the reduction pathway of CO2 and resulted in the enhancement of methanol selectivity and catalytic activity of CO2. The probable pathway for methanol production was proposed as CO2 → *CO2− → *COOH → *CO → *CHO → *CH2O → *OCH3 → CH3OH. This suggests the significance of the ball-milling method during the preparation of better supported catalysts for CO2RR towards those high-valued products. [ABSTRACT FROM AUTHOR]

Thermal cycling can reduce or eliminate thermal stresses in aluminum matrix composites, which is essential to improve the dimensional stability of the composites. In this work, the effect of thermal cycling process on the thermophysical properties of 6092 aluminum alloy/silicon carbide/zirconium tungstate composites was investigated by combining response surface optimization and multi-objective genetic algorithm. The purpose is to elucidate the effects of the process of heating temperature, heating time and cycles on the coefficient of thermal expansion (CTE), micro-strain and thermal conductivity of the composites. A series of robust response models were proposed and verified using analysis of variance, externally studentized residuals distribution and the predicted residuals distribution. According to these models, the heating temperature, heating time and cycles interact in a nonlinear manner concerning on thermophysical properties. The experimental results confirmed that thermal cycling can effectively reduce or eliminate thermal residual stresses in the composites and induce the phase transformation process of zirconium tungstate. The heating temperature plays a dominant role in promoting the thermal mismatch stress release between the metal matrix and the reinforcing particles. The Pareto-optimal hypersurface results on the response surface were obtained according to the non-dominated sorting genetic algorithms (NSGA-II), indicating that the optimal thermal cycling processes were 200 °C, 2 h and 3 cycles with corresponding CTE, micro-strain and thermal conductivity of 20.55 × 10–6/K, 1.16 × 10–3 and 116.68 W/(m K), respectively. [ABSTRACT FROM AUTHOR]

In this work, the precipitates in Ti-Mo-V steel were systematically characterized by high-resolution transmission electron microscopy (HRTEM). The thermodynamics and kinetics of precipitates in Ti-Mo and Ti-Mo-V steels were theoretically analyzed, and the effect of vanadium on the precipitation behavior was clarified. The results showed that the precipitation volume fraction of the Ti-Mo-V steel was significantly higher than that of Ti-Mo steel. The randomly dispersed precipitation and interphase precipitation (Ti, Mo, V)C particles coexisted in the Ti-Mo-V steel. When the temperature was higher than 872 °C, the addition of vanadium could increase the driving force for (Ti, Mo, V)C precipitation in austenite, resulting in an increased nucleation rate and shortened incubation period, promoting the (Ti, Mo, V)C precipitation. When the temperature was lower than 872 °C, the driving force for (Ti, Mo, V)C precipitation in austenite was lower than that for (Ti, Mo)C precipitation, and the incubation period of (Ti, Mo, V)C precipitation was increased. Moreover, it was also found that the precipitated-time-temperature curve of (Ti, Mo, V)C precipitated in the ferrite region was "C" shaped, but that of (Ti, Mo)C was "ε" shaped, and the incubation period of (Ti, Mo, V)C was significantly shorter than that of (Ti, Mo)C.

Neutrophils play a prominent role in the inflammatory response and are a critical factor in the pathogenesis of acute lung injury (ALI). Despite a deep understanding of neutrophil accumulation in the pulmonary microvasculature during the process of this disease, the regulatory mechanism of neutrophil recruitment remains unclear. This study aimed to explore the functions and signaling pathways of the purinergic receptor P2Y 6 in mediating the innate immune response in ALI. P2Y 6 -deficient mice, bone marrow chimeras, and neutrophilic chimeras were created in this work to explore the function of P2Y 6 in ALI. The results indicated that the extracellular nucleotide UDP was released as a dangerous signal and activated P2Y 6 to promote the inflammatory response and pulmonary damage during the process of ALI. P2Y 6 deficiency may mitigate deterioration of this disease, including reduced ALI-related inflammatory factor release and immune cell invasion. Bone marrow and neutrophil chimeras and adoptive transfer in mice showed that P2Y 6 expression on neutrophils contributed to neutrophil infiltration into lung tissues induced by UDP. Further work indicated that P2Y 6 was involved in the neutrophil migration capability through the ErK signaling pathway by mediating the deformation of F-actin filaments and pseudopodia formation during cell recruitment to pulmonary tissue. Here, we provide evidence for the mechanism by which the purinergic receptor P2Y 6 contributes to ALI development by regulating neutrophil infiltration into lung tissues. These data indicated that P2Y 6 might be a potential therapeutic target for the treatment of this acute severe disease., (Copyright © 2022 Elsevier Inc. All rights reserved.)