采用体心坐标系下振动密耦合方法研究低能电子与H2分子高振动激发散射的动量迁移截面(momen-tum transfer cross section,MTCS)。通过对包含18个振动态、8个分波和16个分子对称性的研究,得到了收敛的密耦合框架下的v=0→v′=5,6,7,8,9,1...采用体心坐标系下振动密耦合方法研究低能电子与H2分子高振动激发散射的动量迁移截面(momen-tum transfer cross section,MTCS)。通过对包含18个振动态、8个分波和16个分子对称性的研究,得到了收敛的密耦合框架下的v=0→v′=5,6,7,8,9,10等几个振动跃迁通道的动量迁移截面值,为进一步精确研究低能电子与H2分子的相互作用机理奠定了基础。展开更多
Applicability of the correlation potential,which is currently used in the local density functional theory,to the low-energy electron-atom and molecule scattering is investigated with some examples of scattering proces...Applicability of the correlation potential,which is currently used in the local density functional theory,to the low-energy electron-atom and molecule scattering is investigated with some examples of scattering processes.展开更多
Transient liquid phase(TLP)bonding was investigated in Hastelloy-X samples with different filler metal thicknesses(20,35,50,65,and 100μm)and holding time(5,20,80,320,and 640 min)to obtain optimum bonding parameters.M...Transient liquid phase(TLP)bonding was investigated in Hastelloy-X samples with different filler metal thicknesses(20,35,50,65,and 100μm)and holding time(5,20,80,320,and 640 min)to obtain optimum bonding parameters.Microstructural evaluations using electron probe microanalysis(EPMA)and electron backscattered diffraction(EBSD)show that the central eutectic phases present in the athermally solidified zone(ASZ)are Ni_(3)B,Ni_(2)Si,and CrB,and the precipitates formed in the diffusion-affected zone(DAZ)are MoB,CrB_(2),and Mo_(2)B_(5).According to the results,decreasing the filler thickness as well as increasing the holding time helps realize the completion of isothermal solidification and reduction in the density of precipitates in the DAZ,leading to a joint with more uniform properties.Diffusion of boron and silicon to longer distances with increasing holding time causes the removal of Cr-rich borides in the DAZ and the formation of Mo-rich silicide at the joint interface.Decrease in hardness of ASZ and DAZ due to the elimination of brittle phases in these zones during long holding time causes more uniform hardness distribution in the joint area.The best results are obtained for the sample joined with the 35μm-thick filler metal for 640 min holding time.展开更多
A new modified formulation of the Additivity Rule (AR) was proposed to calculate the total electron scattering cross sections for CH4, CO2, NO2, and N2O, considering the overlapping between atoms in molecules and the ...A new modified formulation of the Additivity Rule (AR) was proposed to calculate the total electron scattering cross sections for CH4, CO2, NO2, and N2O, considering the overlapping between atoms in molecules and the not fully transparency of the molecules. The present calculation covers the range of impact energy from 10 to 3000 eV. The results are compared with experimental data and other theories where available. The atoms are presented by spherical complex optical potential, which is composed of static, exchange, polarization, and absorption terms.展开更多
We report a facile method to synthesize dispersed Fe304@C nanoparticles （NPs）. Fe304 NPs were firstly prepared via the high temperature diol thermal decomposition method. Fe304@C NPs were fabricated using glucose as...We report a facile method to synthesize dispersed Fe304@C nanoparticles （NPs）. Fe304 NPs were firstly prepared via the high temperature diol thermal decomposition method. Fe304@C NPs were fabricated using glucose as a carbon source by hydro- thermal process. The obtained products were characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM）, vibrating sample magnetometer （VSM） and Raman spectra. The results indicate that the original shapes and magnetic property of Fe304 NPs can be well preserved. The magnetic particles are well dispersed in the carbon matrix. This strategy would provide an efficient approach for existing applications in Li-ion batteries and drug delivery. Meanwhile, it offers the raw materials to assemble future functional nanometer and micrometer superstructures.展开更多
文摘采用体心坐标系下振动密耦合方法研究低能电子与H2分子高振动激发散射的动量迁移截面(momen-tum transfer cross section,MTCS)。通过对包含18个振动态、8个分波和16个分子对称性的研究,得到了收敛的密耦合框架下的v=0→v′=5,6,7,8,9,10等几个振动跃迁通道的动量迁移截面值,为进一步精确研究低能电子与H2分子的相互作用机理奠定了基础。
文摘Applicability of the correlation potential,which is currently used in the local density functional theory,to the low-energy electron-atom and molecule scattering is investigated with some examples of scattering processes.
文摘Transient liquid phase(TLP)bonding was investigated in Hastelloy-X samples with different filler metal thicknesses(20,35,50,65,and 100μm)and holding time(5,20,80,320,and 640 min)to obtain optimum bonding parameters.Microstructural evaluations using electron probe microanalysis(EPMA)and electron backscattered diffraction(EBSD)show that the central eutectic phases present in the athermally solidified zone(ASZ)are Ni_(3)B,Ni_(2)Si,and CrB,and the precipitates formed in the diffusion-affected zone(DAZ)are MoB,CrB_(2),and Mo_(2)B_(5).According to the results,decreasing the filler thickness as well as increasing the holding time helps realize the completion of isothermal solidification and reduction in the density of precipitates in the DAZ,leading to a joint with more uniform properties.Diffusion of boron and silicon to longer distances with increasing holding time causes the removal of Cr-rich borides in the DAZ and the formation of Mo-rich silicide at the joint interface.Decrease in hardness of ASZ and DAZ due to the elimination of brittle phases in these zones during long holding time causes more uniform hardness distribution in the joint area.The best results are obtained for the sample joined with the 35μm-thick filler metal for 640 min holding time.
文摘A new modified formulation of the Additivity Rule (AR) was proposed to calculate the total electron scattering cross sections for CH4, CO2, NO2, and N2O, considering the overlapping between atoms in molecules and the not fully transparency of the molecules. The present calculation covers the range of impact energy from 10 to 3000 eV. The results are compared with experimental data and other theories where available. The atoms are presented by spherical complex optical potential, which is composed of static, exchange, polarization, and absorption terms.
基金supported by the National Natural Science Foundation of China(11274033,61227902,11474015)the Research Fund for the Doctoral Program of Higher Education of China(20131102130005)+2 种基金the Fundamental Research Funds for the Central Universities(YWF-14-RSC-119,YWF-15-WLXY-012)China Scholarship Council(201506025052)Beijing Key Discipline Foundation of Condensed Matter Physics
文摘We report a facile method to synthesize dispersed Fe304@C nanoparticles （NPs）. Fe304 NPs were firstly prepared via the high temperature diol thermal decomposition method. Fe304@C NPs were fabricated using glucose as a carbon source by hydro- thermal process. The obtained products were characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM）, vibrating sample magnetometer （VSM） and Raman spectra. The results indicate that the original shapes and magnetic property of Fe304 NPs can be well preserved. The magnetic particles are well dispersed in the carbon matrix. This strategy would provide an efficient approach for existing applications in Li-ion batteries and drug delivery. Meanwhile, it offers the raw materials to assemble future functional nanometer and micrometer superstructures.
