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To solve the data exchange problem of the DGTD method in the periodic structure materials, a new non-conformal boundary data exchange scheme is proposed in this paper refers to previous works. The scheme is easy to implement and does not require third-party mathematical libraries. The numerical results show its effectiveness and accuracy.

It cannot be neglected that the coupling effect and induced current of large-size victim system from the high-altitude nuclear explosion electromagnetic pulse E3 wave. The Newmark method is used to discretize the time axis in finite element time domain method. In this paper, the time step is chose in the order of seconds. This method is used to calculate and analyze the electromagnetic characteristic of E3. Numerical examples show that the applicability and correctness of the algorithm for the calculation of long pulses.

In this work, we compare the behavior of five kinds of high-density spherical ZnO with different surface morphology as anode materials for nickel/zinc rechargeable batteries to investigate the effects of microstructure and surface properties of ZnO on the electrochemical performance of zinc anodes. For the first time, five spherical ZnO samples with tap densities of 1.62, 2.00, 2.38, 2.83, and 3.12 g cm−3 have been successfully developed via a complexing co-precipitation method by adjusting the composition of alkaline solution and pH value. It is discovered that an enhanced volume specific capacity and more stable cycling performance can be achieved for the anode with spherical ZnO (3.12 g cm−3). Nevertheless, the as-obtained ZnO sample with higher tap density shows slightly worse high-rate performance and lower discharge capacity. Interestingly, as confirmed by the CV and Tafel polarization test, with the increase of ZnO’s tap density, the zinc anodes exhibit better reversibility and higher corrosion resistance. Consequently, the denser solid spherical structure of spherical ZnO is beneficial to effectively adjust its “dissolution-deposition” process, significantly suppressing the outward growth of zinc dendrites and enhancing the batteries’ cycling stability.

High-performance ZnO microspheres doped and coated with carbon has been successfully fabricated by a facile three-step process using trisodium citrate as doping carbon source and glucose as coating carbon source. Compared with carbon free ZnO precursor, the resulting ZnO-N 2 @Cmicrospheresexhibitsuperiorrateperformanceandenhancedcyclingstability.(*) At a rate of 10C (5000 mA g −1 ), the ZnO-N 2 @C exhibits specific discharge capacity and volumetric capacities of 283.4 mAh g −1 and 858.7 mAh cm −3 , respectively, while the values for the carbon free ZnO precursor are only 140.2 mAh g −1 and 423.4 mAh cm −3 . After cycling 200 times at 500 mA g −1 , the obtained ZnO-N 2 @C can maintain a satisfying capacity of 508.2 mAh g −1 , corresponding to a superior capacity retention (94.7%). In contrast, carbon free ZnO can only deliver the capacity of 109.4 mAh g −1 and a capacity retention of 24.7% after 200 cycles. This outstanding improvement is attributed to the synergistic effect of the combined in-situ doping and coating carbon, including reduced charge-transfer resistance, enhanced electrochemical reversibility, and better anti-corrosion capabilities. As a result, it is believed that ZnO-N 2 @C should be an attractive and promising anode material for high power Zinc-Nickel batteries.

A new kind of 3D hierarchical flower-like calcium zincate is successfully achieved by a simple microemulsion method. The obtained sample is constructed with many interconnected rhomboid calcium zincate nanosheets with a thickness of 80–100 nm. When served as anode active material for zinc-based battery, the as-prepared calcium zincate delivers superior high-rate properties and improved cycling stability. At 2, 5, 10, 15, 20C, the flower-like calcium zincate shows higher specific discharge capacities of ～297.7, ～254.6, ～232.5, ～202.8 and ～170.5 mAh g−1, respectively, which are significantly higher than those of the conventional hexagon and rhomboid calcium zincate. Especially, after 400 cycles at 1C/1C, the flower-like CZO achieves a capacity retention of 90.8%, whereas the values for the hexagon and rhomboid samples are only 70.2% and 54.7%, respectively. The pronounced high-rate and cycling properties are attributable to its unique 3D hierarchical flower-like structure and small particle size, which leads to the reduced charge transfer resistance, enhanced reversibility, and improved structural stability. Therefore, the proposed 3D hierarchical flower-like calcium zincate is promising anode material with excellent high-rate and cycling properties for advanced zinc-based rechargeable batteries.