A novel pore-array intensified tube-in-tube microchannel (PA) with high throughput was developed to couple with a high-shear mixer (PAHSM) for improving its mixing performance. Effects of structural and operating parameters were intensively investigated with the Villermaux/Dushman system. The results indicated that the mixing performance in PAHSM was significantly impacted by the structural parameters, and it increased with both the rotor speed and flow rate but not with the flow ratio. The micromixing time estimated with the incorporation model could reach 10–4 s. Compared with other mixing devices, the PA liquid distributor can significantly enhance the mixing performance of HSM with high throughput but low pressure drop. An artificial neural network (ANN) was applied to correlate the micromixing time with the investigated parameters, and the comparison between the model and experimental data indicated that it was an efficient method to fit experimental data in the PAHSM.

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Dense networks of deformation twins endow metals and alloys with unprecedented mechanical properties. However, the formation mechanism of these hierarchical twin structures remains under debate, especially their relations with the imperfect nature of twin boundaries (TBs). Here, we investigate the intrinsic deformability of defective TBs in face-centered cubic metallic materials, where the inherent kinks on a set of primary TBs are demonstrated to facilitate the formation of secondary and hierarchical nanotwins. This defect-driven hierarchical twinning propensity is critically dependent on the kink height, which proves to be generally applicable in a variety of metals and alloys with low stacking fault energies. As a geometric extreme, a fivefold twin can be constructed via this self-activated hierarchical twinning mechanism. These findings differ from the conventional twinning mechanisms, enriching our understanding of twinning-mediated plasticity in metallic materials.

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The effects of various structural and operating parameters on liquid–liquid dispersion and selectivity of chemical reactions in inline single-row teethed high shear mixers (HSMs) were studied by a parallel competitive reaction system. The product distribution X S was applied to evaluate the mass transfer characteristics. The results show that X S decreases evidently at first in tandem with a slight increase as the rotor speed and flow rate rise. The results also indicate that the structural parameters of the rotors play a more important role in enhancing the mass transfer efficiency at higher rotor speed. Compared with adjusting other structural parameters, increasing the teeth number of the rotor can most significantly decrease both X S and Sauter mean drop size d 32. Computational fluid dynamics was applied to predict the flow and power characteristics. Furthermore, a dimensionless correlation for X S is established to provide references for the design and optimization of inline HSMs in liquid–liquid systems.

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