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This paper presents scientific analyses of the wall paintings in Wudang Lamasery, which is located in the Baotou area of Inner Mongolia, China. Raman spectroscopy was used to analyze the pigments of the mural of the Lam rim Hall. The results show that vermilion, red lead, chrome yellow, emerald green and synthetic ultramarine were used. The existence of synthetic pigments provides a clue for the date the mural was painted. [ABSTRACT FROM AUTHOR]

A novel core–shell architecture is proposed and proved to be effective in achieving temperature-stable LiF-CaTiO3 microwave dielectric ceramics. Dense CaTiO3 ceramics are initially prepared using the solid-state reaction method and then inserted into the inner core of LiF green pellets. The assembled green pellets are pre-densified using a cold-sintering process (150 °C, 350 MPa, 60 min) and then post-annealed at 800 °C to obtain densified core–shell-structured LiF-xwt%CaTiO3 ceramics (x = 3, 5, 10, 15). The SEM images confirm the core-shelled microstructure, and the excellent chemical compatibility between LiF and CaTiO3 components is revealed from the XRD and EDS results. The large negative temperature coefficient of the resonant frequency of LiF ceramics (− 138 ppm/°C) can be effectively tuned to 2.89 ppm/°C at x = 3, together with a Qf value of 26,580 GHz and εr = 10.89. Therefore, cold sintering and post-annealing treatments open up new ways in designing and constructing novel microwave dielectric ceramics with high performance and should also be instructive in areas, such as ferroelectrics and energy storage ceramics. [ABSTRACT FROM AUTHOR]