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The geometric model of thermal barrier coatings (TBCs) was established. Two cases based on the standard thickness of the ceramic layer existed. These were the steps of TBCs thickness were being higher than the standard layer and those of lower than standard layer. The heat transfer processes of these two cases were simulated with the ANSYS software. The change process of thermal effusivity was analyzed in the two cases and the coating thickness differences effect on the surface temperature distributions of TBCs was analyzed through the time course curves of temperature difference. Moreover, the difficulty of detection for these two cases with infrared nondestructive testing was discussed according to maximum temperature difference and the maximum temperature contrast ratio. The result demonstrated that all curves of thermal effusivity with various thickness differences coincided with each other at the initial and longer times, where the ceramic layer thickness was lower than the standard layer. This was more easily detectable compared to the higher thickness and the maximum temperature contrast ratio or the maximum temperature difference increased as the coating thickness difference increased.

This paper investigates magnetic field and stress-induced magnetic domain reorientation and its correlation with Magnetic Barkhausen Noise (MBN). The magnetic domain dynamics and MBN of grain-oriented transverse and longitudinal electrical steels are studied by using time-resolved magneto-optical imaging. Time and frequency-domain characteristics of MBN signal are investigated for evaluation of stress state and magnetocrystalline anisotropy. Transitions between magnetic domain states with differing tensile stress and magnetic anisotropy directly influence the MBN signal. Its shown that 180° domain wall (DW) reorganization and DW-type conversion generate peaks in the MBN measurement for longitudinal and transverse electrical steel, respectively. The magnetic domain imaging reveals complicated domain arrangement processes in transverse electrical steel. The results provide a physical insight into bulk micromagnetic phenomena.

Land surface temperature is an important indicator for characterizing the habitat conditions and ecological disturbances of ion-adsorbed rare earth mining areas. Because the ions in an ion-adsorbed type rare earth mining area are scattered and the area of a single mining site is small, it is important to obtain practical surface temperature data for monitoring the ecological environment of the area. In this study, Landsat-8 and Gaofen-1(GF-1) satellite images were used as data sources. In view of the characteristics of rare earth mining areas, and the thermal infrared data were used to retrieve the land surface temperature (LST), a land surface temperature downscaling model TDFSU based on remote sensing data fusion and mixed pixel decomposition is proposed. ultimately verifying the quantitative and qualitative accuracy of the downscaled results. The results show that the model can effectively improve the spatial resolution of surface temperature and reflect the spatial differences of surface temperature. This model has high feasibility and applicability in ionic rare earth mining areas.