Good thermoelectric materials should have low thermal conductivity, high electrical conductivity, and Seebeck coefficient, which cannot be easily balanced in bulk materials. Exceptionally, the super-ionics in β-Cu2Se can favorably contribute large ionic electrical conductivity and a liquid-like thermal conductivity by Cu+ ions. In the previous work, the superionic mechanism was found to be enhanced by small and randomly orientated lamellae with alternating ordered Se ion monolayer and disordered Cu ion bilayers. Here, we further enhance the superionic mechanism by increasing and better aligning lamellae in bulk Cu1.94Al0.02Se, resulting in a large thermoelectric figure of merit of 2.62 at 756 °C.

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In order to measure the shock initiation behavior of JOB-9003 explosives, Al-based embedded multiple electromagnetic particle velocity gauge technique has been developed. In addition, a gauge element called the shock tracker has been used to monitor the progress of the shock front as a function of time, thus providing a position–time trajectory of the wave front as it moves through the explosive sample. The data is used to determine the position and time for shock to detonation transition. All the experimental results show that the rising-up time of Al-based electromagnetic particle velocity gauge is very short (<20 ns); the reaction-build-up velocity profiles and the position–time for shock to detonation transition of HMX-based plastic bonded explosive (PBX) JOB-9003 with 1–8 mm depth from the origin of the impact plane under different initiation pressures were obtained with high accuracy.