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To solve high-temperature-induced hazards in mines, heat-insulating materials were prepared by utilising basalt fibres and high-strength ceramsite combined with cementing materials. Through orthogonal tests and data analyses, the optimal combination of the heat-insulating materials doped with basalt fibres was determined as A1B1C1, that is, doping with 45% basalt fibres, a length of the basalt fibres of 6 mm, and doping with 20% ceramsite. The performance indices corresponding to the optimal comprehensive combination of the heat-insulating materials doped with basalt fibres included a density of 1200 kg/m3, thermal conductivity of 0.151 W/(mK), compressive strength of 9.7 MPa, flexural strength of 3.6 MPa, and a water-seepage depth of 25.4 mm. Numerical simulations verified that the materials presented favourable thermal insulation performance.

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Empirical potential is vital to the classic atomic simulation, especially for the study of phase transitions, as well as the solid-interface. In this paper, we attempt to set up a uniform procedure for the validation among different potentials before the formal simulation study of phase transitions of metals. Two main steps are involved: (1) the prediction of the structures of both solid and liquid phases and their mutual transitions, i.e. melting and crystallization; (2) the prediction of vital thermodynamic (the equilibrium melting point at ambient pressure) and dynamic properties (the degrees of superheating and undercooling). We applied this procedure to the testing of seven published embedded-atom potentials (MKBA (Mendelev et al 2008 Philos. Mag. 88 1723), MFMP (Mishin et al 1999 Phys. Rev. B 59 3393), MDSL (Sturgeon and Laird 2000 Phys. Rev. B 62 14720), ZM (Zope and Mishin 2003 Phys. Rev. B 68 024102), LEA (Liu et al 2004 Model. Simul. Mater. Sci. Eng. 12 665), WKG (Winey et al 2009 Model. Simul. Mater. Sci. Eng. 17 055004) and ZJW (Zhou et al 2004 Phys. Rev. B 69 144113)) for the description of the solid–liquid transition of Al. All the predictions of structure, melting point and superheating/undercooling degrees were compared with the experiments or theoretical calculations. Then, two of them, MKBA and MDSL, were proven suitable for the study of the solid–liquid transition of Al while the residuals were unqualified. However, potential MKBA is more accurate to predict the structures of solid and liquid, while MDSL works a little better in the thermodynamic and dynamic predictions of solid–liquid transitions.

To determine the quality and the exact position of interiaces from High Resolution Electron Microscopy (HREM) images. comparison with simulated images is required. In the case of GaAs I AlAs interiaces. the different layers are commonly distinguished by the di.fference in mean intensity between the GaAs and AlAs images. Hov;ever, the mean intensity of a lattice image is influenced by suriace damage resulting from specimen preparation and by inelastic scattering processes. This makes calculation of the mean intensities, and hence comparison between experimental and simulated images, extremely difficult.