A novel way for electrification of mineral particles by electronbeam irradiation was proposed. The effect of irradiation dose oncharge/mass ratio was investigated experimentally. The charge/massratio of electrified mi...A novel way for electrification of mineral particles by electronbeam irradiation was proposed. The effect of irradiation dose oncharge/mass ratio was investigated experimentally. The charge/massratio of electrified mineral powders after irradiation was meas- uredby an instrument based on the principle of electrostatic induction.The experimental results showed that the charge/mass ratio is lar-gely dependent on radiation dose and electric physical properties ofminerals. The mechanism of electrification by electron beam irradi-ation is discussed. it is suggested that the essential ofelectrification by electron beam irradiation is a process ofretardation and charge deposition of incident electrons in materials.展开更多
A novel quasi-opitcal resonance system modified axisymmetrical quasi-optical cavity of oblique ratation(MAQCOR)-is proposed using the laplace integral transormation the kinetic theory of the high relativsitic electron...A novel quasi-opitcal resonance system modified axisymmetrical quasi-optical cavity of oblique ratation(MAQCOR)-is proposed using the laplace integral transormation the kinetic theory of the high relativsitic electron cyclotron maser with MAQCORis carried out within the framowrk of the linearized vlasov-mxawel eauations the formulas of beamwave intreaction power starting current and frequency shift have been derived some important plroblems such as high-order harmonic modes competition inflneces of the rationg angle and space charge and space chrage effcet are andlyaed and discussed in detall and a serios fo new condinsions are obtained a theoretical bssia is laid for the design of this novel qussi-optical gyrotron展开更多
The grain refinement mechanism and texture evolution of electromagnetically formed polycrystalline Cu sheets were investigated using the electron back-scattered diffraction(EBSD) technique. It is found that the averag...The grain refinement mechanism and texture evolution of electromagnetically formed polycrystalline Cu sheets were investigated using the electron back-scattered diffraction(EBSD) technique. It is found that the average grain size decreases from 35.88 μm to 8.77 μm. The grain refinement was mainly attributed to dynamic recrystallization(DRX) at the grain boundary regions of bulged Cu samples where the inhomogeneous dislocation density and the large lattice misorientation were observed. The DRX mechanisms at the grain boundaries were discussed with respect to the strain-induced grain boundary migration nucleation. Moreover, the orientation distribution function(ODF) of the sample with the strain of 50% demonstrated a strong {110}<211> texture and a relatively weak {001}<100> texture. The texture evolution was discussed using the plastic work values of the grains with various orientations, which were calculated according to the Taylor model and the virtual work principle. The experimental results show that the expended plastic work of the grains with {110} orientation is 9.69 MPa, which is distinctly higher than those of the grains with the {001} and {111} orientations. This indicates that the formation of the {110} orientated texture would be preferred with increasing strain in good agreement with the experimental result.展开更多
The formula of input impedance of dipole antenna in Gigahertz Transverse ElectroM agnetic(GTEM) cell based on the dyadic Green's function is first obtained in this paper. The validation of the formula is verified ...The formula of input impedance of dipole antenna in Gigahertz Transverse ElectroM agnetic(GTEM) cell based on the dyadic Green's function is first obtained in this paper. The validation of the formula is verified by the results of theoretical derivation and simulation with well agreements. In comparison with the formula of input impedance in free space, the relationship between the change of input impedance with the length of antenna and the position of antenna in GTEM cell is obtained. In addition, some meaningful conclusions are presented, which not only can be referred by the further research of ElectroM agnetic Interference(EMI) measurements in GTEM cell, but also provide the theoretical basis for testing compensation and error analysis.展开更多
基金[This work was financial supported by the National Natural Science Foundation of China (No.59874002).]
文摘A novel way for electrification of mineral particles by electronbeam irradiation was proposed. The effect of irradiation dose oncharge/mass ratio was investigated experimentally. The charge/massratio of electrified mineral powders after irradiation was meas- uredby an instrument based on the principle of electrostatic induction.The experimental results showed that the charge/mass ratio is lar-gely dependent on radiation dose and electric physical properties ofminerals. The mechanism of electrification by electron beam irradi-ation is discussed. it is suggested that the essential ofelectrification by electron beam irradiation is a process ofretardation and charge deposition of incident electrons in materials.
基金the National Natural Science Foundation of China the Doctoral Fund of Education Committee of China
文摘A novel quasi-opitcal resonance system modified axisymmetrical quasi-optical cavity of oblique ratation(MAQCOR)-is proposed using the laplace integral transormation the kinetic theory of the high relativsitic electron cyclotron maser with MAQCORis carried out within the framowrk of the linearized vlasov-mxawel eauations the formulas of beamwave intreaction power starting current and frequency shift have been derived some important plroblems such as high-order harmonic modes competition inflneces of the rationg angle and space charge and space chrage effcet are andlyaed and discussed in detall and a serios fo new condinsions are obtained a theoretical bssia is laid for the design of this novel qussi-optical gyrotron
基金Funded by the National Fundamental Research Program of China(No.2011CB012806)
文摘The grain refinement mechanism and texture evolution of electromagnetically formed polycrystalline Cu sheets were investigated using the electron back-scattered diffraction(EBSD) technique. It is found that the average grain size decreases from 35.88 μm to 8.77 μm. The grain refinement was mainly attributed to dynamic recrystallization(DRX) at the grain boundary regions of bulged Cu samples where the inhomogeneous dislocation density and the large lattice misorientation were observed. The DRX mechanisms at the grain boundaries were discussed with respect to the strain-induced grain boundary migration nucleation. Moreover, the orientation distribution function(ODF) of the sample with the strain of 50% demonstrated a strong {110}<211> texture and a relatively weak {001}<100> texture. The texture evolution was discussed using the plastic work values of the grains with various orientations, which were calculated according to the Taylor model and the virtual work principle. The experimental results show that the expended plastic work of the grains with {110} orientation is 9.69 MPa, which is distinctly higher than those of the grains with the {001} and {111} orientations. This indicates that the formation of the {110} orientated texture would be preferred with increasing strain in good agreement with the experimental result.
基金Supported by Chinese Academy of Sciences(No.Y140110213)
文摘The formula of input impedance of dipole antenna in Gigahertz Transverse ElectroM agnetic(GTEM) cell based on the dyadic Green's function is first obtained in this paper. The validation of the formula is verified by the results of theoretical derivation and simulation with well agreements. In comparison with the formula of input impedance in free space, the relationship between the change of input impedance with the length of antenna and the position of antenna in GTEM cell is obtained. In addition, some meaningful conclusions are presented, which not only can be referred by the further research of ElectroM agnetic Interference(EMI) measurements in GTEM cell, but also provide the theoretical basis for testing compensation and error analysis.
