Magnetic dynamic properties of Fe nanorings with small defects were simulated with Monte Carlo method. It is found that hysteresis loops of small defect Fe nanoring have "bistable" characteristics, which is consistent with experimental results. Energy research shows that vortex states appear in the region of local energy minimum. Remanence of defect system changes with defect location: The remanence increases first and then decreases with the increase of Y, and remains relatively stable in the middle region. Spin configuration of the system explains the above phenomenon well.

Numerical Hankel transform for circularly symmetric system at variable sampling intervals in input and optput planes is presented. An improved hybrid algorithm by using quasi Gradient Decent algorithm and spectrum selectivity is applied to the design of pure phase elements (PPE) in uniform illumination. Considering heat conductivity the simulated result shows that 97.2% of the incident beam energy is homogeneously concentrated into the desired focal spot in the target plane, and it fits to the required profile with the top profile error 1.1%.

A new numerical computational Method,Differential Quadrature Domain Decomposition Method,is presented based on the advantages of Differential Quadrature Method and Domain Decomposition Method.Numerical examples find the method is more convenient and efficient for a kind of free boundary problems of parabolic equation with weak singularity in the initial value.

A random fractal model of the drop size and space distribution in dropwise condensation is presented.The boundary conditions of heat conduction through the condensate wall are defined by use of the heat transfer model through a single drop proposed by Rose.Thus,the mathematical model of dropwise condensation heat transfer is established.A numerical simulation of dropwise condensation heat transfer of water on the copper wall has been performed.The results agree well with the bulk of existing experimental data and the precision is higher than that of the model proposed by Rose.

The computation is clarified for the electron beam density modulation in optical klystron on storage ring free electron laser with three different methods,and the effects of electron beam parameters on density modulation are also studied.The numerical results show that the three dimensional simulation is necessary.

The generation of pulsed high-energy-density plasma by electromagnetic implosion of cylindrical gas shell (i.e.,hollow Z pinches)has been investigated theoretically using a one-dimensional code proposed here.The main mechanism of EM implosion process involves hydrodynamics,radiation in the collapsing plasma,and equation of LR circuit.The discrepancy between the numerically computed results and the experementally measured results is found to be less than 10%.It is shown that this code can be used as a tool to design new EM implosion device.

Sub-critical breeder fuelling actinide series and driven by D-T fusion neutrons can use uranium source effectively.Due to k_eff less than 1 and low blanket power density,it has good safety quality.Because of the strong neutron breeding capability,the breeder can be driven by a small neutron source.With a 50~100 M Wt fusion core,the reactor can produce 1 GWe energy,1000 kg fertile to support 3~4 PW Rs as the same power,and burn actinides produced by 3~4 PW Rs.At the same time,the reactor blanket can also produce sufficient tritium for fusion reaction.

The theoretical analyses of the beam emittance on SG-1 FEL device have been presented in this paper. The measured beam emittance is about (0.4-0.5) rad·cm. From the experimental beam quantity and numerical simulation resalt, it appears that the quantity of beam current is good enough to abandom the 9-m-long beam modulated system, while substituting with 2-m-long drifting focusing regiou.