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Carbon fibre-reinforced plastic (CFRP) composites, prized for their exceptional properties, often encounter surface quality issues during slotting due to their inherent heterogeneity. This paper tackles CFRP slotting challenges by employing multi-tooth mills in experiments with various fibre orientations and tool feed rates. In-plane scratching tests are performed under linearly varying loads; then, slotting experiments are conducted at different parameters. The scratching test results indicate that the fibre orientation and cutting angles have significant influences on forces and fracture process. The slotting experiments demonstrate that cutting forces and surface roughness Sa of the bottom slotting surface are notably affected by the fibre orientation, with disparities between up-milling and down-milling sides. Reorganising Sa data by local fibre cutting angle θ highlights consistent Sa variations between up-milling and down-milling sides for 0° ≤ θ ≤ 90°, with lower Sa on the up-milling side. However, for 90° < θ ≤ 150°, Sa variations diverge, with lower Sa on the down-milling side. Unexpectedly, Sa on the down-milling side decreases with increasing θ in this range. Additionally, the tool feed rate exerts a more pronounced influence on Sa on the up-milling side. [ABSTRACT FROM AUTHOR]

Wear resistance and wet grip resistance are the main properties of tires, but they are often contradictory and difficult to synergize. In this paper, drawing on the bionics concept, the bionic topography of the pits was introduced into the design of the tread rubber structure, and the synergistic improvement mechanism of the tire tread rubber with the bionic pit structures was explored. The overall performance improvement of tread compounds provided a new approach. The research showed that the designed high wear resistance tire tread compounds W2 had the best wear resistance, and the high wet grip resistance tire tread compounds S3 had the best‐wet grip resistance. When the diameter of the bionic unit was 2.5 mm and the pit number was 6, the wear resistance rate of the sample was the highest (about 11.86%), and the wear amount was 70.6; the maximum wet friction coefficient of the sample sliding on the sandpaper surface and the smooth glass surface was 0.834 and 0.71, the corresponding wet grip resistance improvement rates were also 11.89% and 12.34%, respectively. Experiments have proved that the tire tread compounds with the bionic pit structures composed of W2S3 can effectively synergistically improve wet grip resistance and wear resistance. [ABSTRACT FROM AUTHOR]

The materials or bionic methods available cannot further solve the contradiction between the wear resistance and wet resistance of tire tread compounds. In this study, a convex‐hull bionic tire tread compound was designed and produced according to the difference in wear resistance between two types of tire tread compounds. The effects of the bionic structure on the wear resistance and wet resistance of the tire tread compounds were explored by analyzing the changes in wear loss, wear surface characteristics, and wet friction coefficient. The wear resistance and wet resistance of the convex‐hull bionic tire tread compound were collaboratively improved. The largest increasing rate of wear resistance was 9%, and the largest increasing rates of wet sliding ability on sand paper surface and on smooth glass surface were 3.4% and 4.2%, respectively. The coupling design of materials and bionic structures offers a new way to improve the overall performances of tire tread compounds. [ABSTRACT FROM AUTHOR]

We introduce the background of Shanghai medical purchasing service and supervision platform (later we call it "open platform") and the effect of its implementation. We also analyze the problems occurred by medical institutions in the management of supplies, explore how to use open platform to strengthen the management of medical supplies, further optimize the structure of supplies, standardize the clinical reasonable use and charges, and ensure the quality, safety and traceability of supplies.