To study system-generated electromagnetic pulse(SGEMP) produced by complex model, a 3D particle in cell (PIC) code is exploited. A function module is appended to characterize cosine angular distribution and exponential energy spectra of photoelectron. For validation, external SGEMP effects induced by photoelectrons emitted from cylinder top surface is simulated and are compared with those by 2D code from literature. Subsequently, external SGEMP effects induced by photoelectrons emitted from half-side surface of a cylinder are studied. It shows that intense of electric field could get 56 kV·m^-1 and magnetic field is 3.0×10^-6T as emitting current is 3.3 A.

Structural,elastic,and electronic properties of B4,B3,and B1 ZnO under 0~15 GPa are studied with first-principles method combined with energe-of-state and elastic calculations.It shows that under 0~15 GPa,the energy of B4 ZnO is always lower than that of B3 ZnO.Either B4 or B3 transforms to B1 at a critical pressure,i.e.,11.8 GPa for B4 and 12.4 GPa for B3.As B4 transforms to B1,volume of the system reduces to about 88.3% of the initial value.The results agree with available experimental and theoretical data.The shear modulii reduce rapidly as the pressure is larger than 6 GPa,which means that some structural change may happen.It agrees with recent experimental results.Electronic properties show that the interaction between Zn 3d and O 2p reduces as the pressure increases.