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High-strength aluminum alloy have become one of the most commonly used metal materials for aerospace and automotive application parts due to its high strength， low density， excellent ductility and corrosion resistance. Wire arc additive manufacturing （WAAM） has the ability to rapidly in-situ form and manufacture complex structural parts， and is very suitable for the manufacturing of medium or large high-strength aluminium alloy parts. The current status of high-strength aluminum alloy WAAM processes and equipment， the inherent properties and defects of high-strength aluminum alloy WAAM， and the main performance optimization methods were comprehensively analyzed in this paper. The inherent characteristics of the microstructure and properties as well as the impact of hybrid additive manufacturing technologies on the microstructure and properties were discussed. Opinions are put forward on issues such as metallurgical defects， characteristic performance requirements， the advantages and disadvantages of various optimization processes in WAAM. Development directions such as a comprehensive evaluation system， composition design and wire development， special heat treatment systems and synergy of composite additive manufacturing technology are proposed. Such proposals are expected to provide references for the performance improvement and application promotion of high-strength aluminum alloys manufactured via WAAM.

Epigenetics is a biological process that modifies and regulates gene expression, affects neuronal function, and contributes to pain. However, the mechanism by which epigenetics facilitates and maintains chronic pain is poorly understood. We aimed to determine whether [N.sup.6]-methyladenosine (m6A) specifically modified by methyltransferase-like 14 (METTL14) alters neuronal activity and governs pain by sensitizing the GluN2A subunit of the N-methyl-D-aspartate receptor (NMDAR) in the dorsal root ganglion (DRG) neurons in a model of chemotherapy-induced neuropathic pain (CINP). Using dot blotting, immunofluorescence, gain/loss-of-function, and behavioral assays, we found that m6A levels were upregulated in L4-L6 DRG neurons in CINP in a DBP/METTL14-dependent manner, which was also confirmed in human DRGs. Blocking METTL14 reduced m6A methylation and attenuated pain hypersensitivity. Mechanistically, METTL14-mediated m6A modification facilitated the synaptic plasticity of DRG neurons by enhancing the GluN2A subunit of NMDAR, and inhibiting METTL14 blocked this effect. In contrast, overexpression of METTL14 upregulated m6A modifications, enhanced presynaptic NMDAR activity in DRG neurons, and facilitated pain sensation. Our findings reveal a previously unrecognized mechanism of METTL14-mediated m6A modification in DRG neurons to maintain neuropathic pain. Targeting these molecules may provide a new strategy for pain treatment., Introduction Chemotherapy-induced neuropathic pain (CINP) is a debilitating complication caused by damage to the peripheral nervous system by chemotherapeutic agents, including paclitaxel (1). CINP occurs in approximately 50% to 90% [...]

Carbon hydrocarbon compounds, especially low-carbon hydrocarbons (C1–C3), are vital raw materials in the petrochemical industry, but their efficient separation has great challenges due to their similar molecular structures and properties. In contrast to traditional low-temperature distillation and absorption separation technologies, selective adsorption employing porous materials as adsorbent has the advantages of low energy consumption, high efficiency, and high selectivity, indicating broad application possibilities in the field of low-carbon hydrocarbon separation. In this paper, the recent progress in the separation and purification of hydrocarbon mixtures by means of the two kinds of porous materials (metal–organic frameworks and molecular sieves) that have been widely used in recent years is reviewed, including purification of methane and separation of ethylene/ethane, propylene/propane, and some high-carbon hydrocarbon isomers. The structure–activity relationships between their chemical composition, structural characteristics, and separation performance are discussed to understand the separation mechanism. In conclusion, the issues encountered in the application of metal–organic frameworks and molecular sieves in the separation of low-carbon hydrocarbons are discussed in light of the current context of "carbon neutrality". [ABSTRACT FROM AUTHOR]

The separation of mixtures with close boiling points is a critical task in the petrochemical industry, and one such mixture that requires separation is o-xylene/styrene. The STED process is used to separate o-xylene/styrene, which contains a certain amount of organic sulfur in the product due to the limitations of the process. In this study, the process underwent enhancements to attain the effective separation of styrene and accomplish deep desulfurization. A mixture of sulfolane (SUL) and N-methylpyrrolidone (NMP) was selected as the extraction solvent after calculating the UNIFAC group contributions. An orthogonal experiment was conducted to investigate the effects of the solvent/oil ratio, reflux ratio, water addition rate, and solvent ratio on the product. The correspondence between each factor and the indexes examined was determined, enabling the optimization and prediction of the styrene product quality. The final optimized conditions for the extractive distillation column are as follows: solvent/oil ratio of 7, reflux ratio of 4.5, water addition rate of 6000 kg/h, and a solvent ratio of 9:1. Under optimal conditions, the purity of the product was observed to be greater than that of the original process and the sulfur content of the product can be reduced to lower than 10 ppm at the cost of an increase of 12.31% in energy consumption. [ABSTRACT FROM AUTHOR]