We study type I clathrate Ba8Cu5.1Ge40.2Sn0.7 single crystals (space group Pm3̄n, no. 223, a = 10.7151(3)) grown using a Sn flux method, and the thermoelectric figure of merit ZT of single crystals reaches a maximum value of 0.6 at 773 K.

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With the advancement of electrode materials for lithium-ion batteries (LIBs), it has been recognized that their surface/interface structures are essential to their electrochemical performance. Therefore, the engineering of their surface by various coating technologies is the most straightforward and effective strategy to obtain the desirable battery characteristics. Coating the electrode materials' surface to form a specifically designed structure/composition can effectively improve the stability of the electrode/electrolyte interface, suppress structural transformation, improve the conductivity of the active materials and consequently lead to enhanced cycle stability and rate capability of LIBs. However, due to the restrictions of conventional coating methods, it is still very hard to obtain a conformal and multifunctional coating layer. This paper focuses on recent advances and summarizes the challenges in the development of surface coating technologies for LIBs. Based on these factors, the new concepts of 'ultrathin conformal coating', 'continuous phase coating' and 'multifunctional coating' are proposed and discussed, followed by the authors' rational perspectives on the future development and potential research hot spot in the surface/ interface engineering of LIB materials and systems.

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Based on the structure of permanent magnet (PM) spring, composed of one fixed end magnet and one moving magnet, a nonlinear resonant electromagnetic micro-generator is designed, which is suitable for human wrist vertical shaking and can be used as an emergency power source for portable electronic products, such as cell phone. Generator model is built under the condition of resistive load, which has been solved numerically through simulation. The model is validated by the measured results and can be used for further study of generator optimization and power processing circuits. The experimental results show that the prototype could generate power as high as 50 mW under the condition of simple harmonic driving acceleration with the amplitude of 0.8g(7.84 m/s2) and the frequency of 3.33 Hz.

Magnetoacoustic Tomography (MAT) is a new imaging method. MAT combines the good contrast of electrical impedance tomography with the good spatial resolution of ultrasound imaging. Magnetoacoustic Tomography includes Magnetoacoustic Tomography with magnetic induction and Magnetoacoustic Tomography with injecting current. In this paper we researched the later imaging method mainly; in paper we studied the parameters of AC power supply, which was injected to the imaging sample. At the same time, the waveforms of experiment were given and analyzed, which provides theoretical basis for the selection of power supply used in the subsequent experiments.