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Spark plasma sintering (SPS) of pure commercially sub-micron B₄C powder at 1700–1900${}^{\circ }$C for 20min has been conducted and their wear properties have been investigated by reciprocating friction and wear test. It was found that the relative density increased with the increase and the grain size increased a little at 1700–1900${}^{\circ }$C. Wear mechanisms in the temperature range of 1700–1900${}^{\circ }$C have been proposed such that at 1700${}^{\circ }$C the wear mechanism was dominated by plastic deformation and intergranular fracture, while at 1800–1900${}^{\circ }$C there was transition to the surface fracture or grain pull-out. A model for the spherical abrasive wear was proposed to describe the friction and wear of the B₄C ceramics which is well-fitting with the experimental results.

Bi₂O₃ nanomaterials with a diversity of morphologies, such as nanoparticles, nanorods and nanoplates, were controllably synthesized successfully by a reverse microemulsion route. X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM), and thermogravimetry differential thermal analysis (TG-DTA) were employed to characterize the obtained products. It was found that the size and morphology of bismuth oxide were affected mainly by water content (W₀), and the shape of Bi₂O₃ changed with different W₀. The common role of surfactant adsorbing on the surface of the nanoparticles led to the formation of Bi₂O₃ nanomaterials with specific morphologies. The possible formation mechanisms of these nanostructures were also discussed. With calcination temperature increasing from 275 °C to 350°C, β-Bi₂O₃ has transformed into α-Bi₂O₃ completely.

Buton rock asphalt (BRA) is usually used as modifier applied to bitumen and bituminous mixture. In this paper, the performance of hot in-plant recycling mixture modified by buton rock asphalt are evaluated using rutting test, immersion Marshall test and freeze-thaw split test. The modification mechanisms of buton rock asphalt are studied by element analysis, scanning electron microscope analysis and infrared spectrum analysis. The test results showed that buton rock asphalt could improve the rutting resistance and the ability to anti-water damage of hot in-plant recycling mixture. The combined actions of rock asphalt and RAP asphalt lead to the improvement of high-temperature stability. The high-temperature softening and miscellaneous clusters adsorption of buton rock asphalt reinforce the bonding of asphalt and aggregate, and the rock asphalt powder absorbs asphalt to increase binder viscosity and reduce flow ability, thus improving the moisture susceptibility of asphalt mixture.