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The measurement method and quantitative indexes of iron ore consolidation characteristic temperature (CCT) during roasting, including consolidation starting temperature, highest consolidation rate temperature, and consolidation termination temperature, were improved based on previous research. The mineral properties of V–Ti magnetite (Panzhihua) were analyzed, and the CCT of V–Ti magnetite was calculated. To investigate the effect of mineral types on CCT, a series of trials were carried out by using various ores, including high-grade magnetite ore, high silicon iron ore, and V–Ti magnetite ore. The greatest shrinkage of V–Ti magnetite was 6.7%, the consolidation starting temperature was 991 °C, and the termination temperature was 1384 °C. The results of X-ray diffraction analysis indicated that the V–Ti magnetite ore was composed of titanomagnetite, peridotite, and other minerals, which is more complicated than conventional magnetite. As a result, the temperature at the maximum rate of consolidation and the temperature at the termination of consolidation are the greatest. FeTiO3and MgFe2O4in V–Ti magnetite may inhibit the creation of sinter necks between hematite particles. Liquid phase occurs inside the pellet when the temperature surpasses 1250 °C, which may accelerate particle growth and the formation of a sintering neck within the pellets.

Methods of experimental observations, theoretical analysis and meso-scale modeling were used to study the propagation processes of shock waves in dry and wet sandstone under dynamic impact in this paper. According to the results from the dynamic impact experiments with velocity of 0.2–0.5 km/s, it was found that the velocity of shock wave increases linearly with water content. Additionally, the velocity of the shock wave in the sandstone showed a linearly increased regularity with the increasement of the impact velocity, which was proved by theory in this paper. Furthermore, meso-scale simulation models were performed and the simulation results showed that sandstone's porosity reduced the shock waves velocity compared to nonporous materials. Pore space filled with water counteracts the effects of porosity, resulted in larger shock wave velocity.

Hydroxyapatite coatings with biological activity on magnesium alloy can effectively reduce its degradation rate in the physiological environment. Pre-calcification was applied as the pretreatment in this paper. And then, hydroxyapatite coatings were deposited on the surface of the magnesium alloy in non-magnetic field, near the antarctic and the arctic of a constant magnetic field respectively. The morphology, phase composition and crystal structure of the coatings were analyzed using SEM and XRD. The results show that the crystals of the coatings affected by the magnetic fields are preferential orientation significantly.

Microstructure evolution characteristics and the influence of the intial grain size on the dynamic recrystallization of AZ31 were investigated by rolling at deformation temperature of 280 °C, 30% reduction and strain rate of 5.6s-1. The results indicate that under the present deformation condition, when the grain size is 6.2μm the dynamic recrystallization does not occur , twinning dynamic recrystallization (TDRX) occurs when the original grain size are of 7.9μm and 12.7μm, when the original grain size is 21.1μm rotating dynamic recrystallization (RDRX) occurs.

Soil particle transport causes serious environmental problems, and particle interaction forces will be the controlling force for soil transport during rainfall. However, few reports can be found in literature concerning the quantitative evaluation of particle interaction forces on soil particle transport. In this study, purple soil was adopted to study soil particle transport under different force strength conditions of particle interaction during rainfall simulation with precipitation intensity of 150 mm h–1for 110 min. We first analyzed soil particle interaction forces quantitatively under different KNO3and Ca(NO3)2concentrations (0.0001, 0.001, 0.005, 0.01, 0.05, 0.1, and 1 mol L–1) which adjusted surface potential of soil particle from –323 to –50 mV. The results indicated that the net Derjaguin–Landau–Verwey–Overbeek (DLVO) force could not solely cause soil particle transport during rainfall. The hydration repulsive force, which was much stronger than the DLVO force, played a crucial role in soil particle transport. During rainfall, soil particle in aggregate was separated to a distance of 1.5 to 2 nm by the strong hydration repulsive force (swelling process). Then aggregate was thoroughly broken by the electrostatic repulsive force. The hydration repulsive force dominated aggregate swelling, and the electrostatic force determined the transport intensity. We found that, at surface potentials lower than –100 mV, soil transport did not occur even precipitation intensity reaching 150 mm h–1; and –200 mV of surface potential was the critical potential for soil particle transport. We conclude that the surface hydration force and electrostatic repulsive force were the controlling force for soil particle transport during rainfall.

Rapid deposition of hydroxyapatite on Mg-alloy in concentrated simulated body fluid (5×SBF) and modified simulated body fluid (m-SBF) was investigated. By biomineralization method, hydroxyapatite coating was deposited on Mg-alloy with pre-calcification treatment. Scanning electron microscope (SEM), energy disperse spectroscopy (EDS) and X-ray diffraction instrument (XRD) were applied to analyze the deposition product of biomineralization and the related mechanism. The results showed that pre-calcification treatment on Mg-alloy can lead to a quite rapid deposition of hydroxyapatite. Ionic concentrations in SBF solutions affected the structure of hydroxyapatite greatly. A homogeneous plate-like apatite coating was induced on Mg alloy sample in m-SBF solution which is promising for the future practice.