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China's Central Bank Issues Additional Rule on QFII Custodianship
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《China & World Economy》 SCIE 2003年第1期56-56,共1页
China’s central bank issued an additional regulation recently concerning the Qualified Foreign Institutional Investor (QFH) scheme, clarifying key procedural matters when banks apply for a custodian’s role.The gover... China’s central bank issued an additional regulation recently concerning the Qualified Foreign Institutional Investor (QFH) scheme, clarifying key procedural matters when banks apply for a custodian’s role.The government has unveiled the long-awaited reform in the early Nov. 2002, allowing foreigners through such QFHs to trade its A. shares and bonds. Six banks, including three Chinese and three foreign ones, have already applied to 展开更多
关键词 QFII BANK in China’s Central Bank Issues additional rule on QFII Custodianship rule on
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Additivity rule for electron-molecule total cross section calculations at 50-5000 eV: a new geometrical approach
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作者 施德恒 孙金锋 +1 位作者 朱遵略 刘玉芳 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第6期2103-2109,共7页
Taking into consideration the changes of the geometric shielding effect in a molecule as the energy of incident electrons varies, this paper presents an empirical fraction, which depends on the energy of incident elec... Taking into consideration the changes of the geometric shielding effect in a molecule as the energy of incident electrons varies, this paper presents an empirical fraction, which depends on the energy of incident electrons, the target's molecular dimension and the atomic and electronic numbers in the molecule. Using this empirical fraction, it proposes a new formulation of the additivity rule. Employing the new additivity rule, it calculates the total cross sections of electron scattering by C2H4, C6H6, C6H14 and C8H18 over the energy range from 50 to 5000eV. In order to exclude the calculation deviations caused by solving the radial Schrodinger equation of electron scattering by atoms, here the atomic cross sections are derived from the experimental total cross section results of simple molecules (H2, O2, CO) via the inversion algorithm. The quantitative total cross sections are compared with those obtained by experiments and other theories, and good agreement is obtained over a wide energy range, even at energy of several tens of eV. 展开更多
关键词 electron scattering total cross section additivity rule geometric shielding effect
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Total cross sections for electron scattering from fluoromethanes:A revised additivity rule method
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作者 谭晓明 赵刚 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第6期167-171,共5页
The additivity rule for electron-molecule scattering is revised by considering the difference between the free atom and the bound atom in the molecule. The total cross sections for electron scattering from fluorometha... The additivity rule for electron-molecule scattering is revised by considering the difference between the free atom and the bound atom in the molecule. The total cross sections for electron scattering from fluoromethanes (CF4, CF3H, CF2H2, and CFH3) are calculated in an energy range from 100 eV to 1500 eV by the revised additivity rule. The present calculations are compared with the original additivity rule results and the available experimental data. Better agreement with each other is obtained. 展开更多
关键词 total cross section electron scattering revised additivity rule
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An Empirical Formula Approach to Total Cross Sections for Electron Scattering on Polyatomic Molecules
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作者 杜朝玲 孙金锋 +2 位作者 刘玉芳 程光煦 陈延峰 《Chinese Physics Letters》 SCIE CAS CSCD 2005年第11期2801-2804,共4页
Considering the real experimental process of e-molecule scattering a new empirical formula has been developed to calculate the total cross sections (TOSs) for electron scattering on polyatomic molecules (CH4, C2H2,... Considering the real experimental process of e-molecule scattering a new empirical formula has been developed to calculate the total cross sections (TOSs) for electron scattering on polyatomic molecules (CH4, C2H2, CH3OH and CH3F). The present results are compared with other available theoretical results and experimental data. The new formula incorporates an energy factor f(E) to represent the elastic and inelastic changing process during experiments. It depends on no adjustable parameters and has also extended the validity of the empirical approaches to lower energy range further. 展开更多
关键词 HYDROCARBON MOLECULES INTERMEDIATE ENERGIES ADDITIVITY rule CO C2H2 N-2 COLLISIONS POSITRONS
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A modification potential method of calculating total cross sections of electrons scattering from complex molecules C2H6, C2F6, C6H6 and C6F6 at 100 eV-5000 eV
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作者 施德恒 孙金锋 +2 位作者 朱遵略 刘玉芳 杨向东 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第6期1278-1283,共6页
A complex optical model potential modified by incorporating the concept of bonded atom, which takes into consideration the overlapping effect of electron clouds between two atoms in a molecule, is first employed to ca... A complex optical model potential modified by incorporating the concept of bonded atom, which takes into consideration the overlapping effect of electron clouds between two atoms in a molecule, is first employed to calculate the total cross sections for electrons scattering from such complex molecules as C2H6, C2F6, C6H6 and C6F6 using the aclditivity rule model at Hartree-Fock level over the energy range from 100 eV to 5000 eV. The total cross sections are quantitatively compared with those obtained by experiments wherever available, and they are in good agreement with each other over a wide energy range. It is shown that the modified potential together with the additivity rule model is completely suitable for the calculation of total cross sections of electrons scattering from such complex molecules as C2H6, C2F6, C6H6 and C6F6 above 200 eV-300 eV. 展开更多
关键词 total cross section electrons scattering additivity rule atomic and molecular collision
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Total cross sections for electrons scattering from simple molecules containing the larger atom sulfur at 30-5000eV
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作者 施德恒 刘玉芳 +2 位作者 孙金锋 杨向东 朱遵略 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第11期2208-2213,共6页
A complex optical model potential modified by the concept of bonded atom, which takes into consideration the overlapping effect of electron clouds, is employed to calculate the total cross sections for electrons scatt... A complex optical model potential modified by the concept of bonded atom, which takes into consideration the overlapping effect of electron clouds, is employed to calculate the total cross sections for electrons scattering from simple molecules (SO2, H2S, OCS, CS2 and SO3) containing the larger atom, sulfur, at 30-5000eV by using the additivity rule model at Hartree-Fock level. The quantitative molecular total cross section results are compared with those obtained in experiments and other calculations wherever available, and good agreement is obtained. It is shown that the additivity rule model together with the complex optical model potential modified by the concept of bonded atom can give the results closer to the experiments than the one unmodified by it. So, the introduction of bonded-atom concept in complex optical model potential betters the accuracy of the total cross section calculations of electrons from the molecules containing the larger atom, sulfur. 展开更多
关键词 atomic and molecular collision additivity rule bonded atom total cross section
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Absolute differential, elastic integrated and mqment transfer cross sections for electron-OCS collisions at intermediate and high energies
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作者 施德恒 孙金锋 +3 位作者 朱遵略 马恒 刘玉芳 杨向东 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第6期1655-1659,共5页
A complex optical model potential modified by incorporating the concept of bonded atom, which takes into consideration the overlapping effect of electron clouds between atoms in a molecule, is firstly employed to calc... A complex optical model potential modified by incorporating the concept of bonded atom, which takes into consideration the overlapping effect of electron clouds between atoms in a molecule, is firstly employed to calculate the absolute differential, elastic integrated and moment transfer cross sections for electron scattering by OCS over the incident energy range from 200 to 1000 eV using the additivity rule model at Hartree-Fock level. The calculated results are compared with those obtained by experiment and other theories wherever available, and good agreement is obtained over a wide energy range. It is shown that the additivity rule model together with the modified potential is completely suitable for calculating the absolute differential, elastic integrated and moment transfer cross sections of electron scattering by molecules such as OCS. 展开更多
关键词 electron scattering additivity rule differential cross section elastic integrated cross section
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A Modified Potential Method for Electrons Scattering Total Cross Section Calculations on Several Molecules at 30 ~ 5000 eV: CF4, CCl4, CFCl3, CF2Cl2, and CF3Cl
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作者 MA Heng SHI De-Heng +2 位作者 SUN Jin-Feng LIU Yu-Fang ZHU Zun-Lue 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4期697-701,共5页
A complex optical model potential modified by the concept of bonded atom, which takes into consideration the overlapping effect of electron clouds between two atoms in a molecule, is employed to calculate the total cr... A complex optical model potential modified by the concept of bonded atom, which takes into consideration the overlapping effect of electron clouds between two atoms in a molecule, is employed to calculate the total cross sections (TCS5) for electrons scattering from several molecules (CF4, CCl4, CFCl3, CF2 Cl2, and CF3 Cl) over an incident energy range 30 - 5000 eV using the additivity rule model at Hartre-Fock level. The quantitative TCS5 are compared with those obtained by experiments and other theories wherever available, and good agreement is obtained above 100 eV. It is shown that the modified potential can successfully calculate the TCS5 of electron-molecule scattering over a wide energy range, especially at lower energies. 展开更多
关键词 total cross section additivity rule atomic and molecular collision
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A Correlation Potential Method for Electron Scattering Total Cross Section Calculations on Several Diatomic and Polyatomic Molecules over Energy Range 10~5000eV
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作者 LIUYu-Fang SHIDe-Heng +2 位作者 SUNJin-Feng ZHUZun-Lue YANGXiang-Dong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2期309-314,共6页
A complex optical model potential correlated by the concept of bonded atom, which considers the overlapping effect of electron clouds between two atoms in a molecule, is firstly employed to calculate the total cross s... A complex optical model potential correlated by the concept of bonded atom, which considers the overlapping effect of electron clouds between two atoms in a molecule, is firstly employed to calculate the total cross sections for electron scattering on several molecules (NH3, H2O, CH4, CO, N2, O2, and C2H4) over the energy range 10 ~ 5000 eV using the additivity rule model at Hartree-Fock level. The difference between the bonded atom and the free one in states is that the overlapping effect of electron clouds of bonded atoms in a molecule is considered. The quantitative total cross sections are compared with the experimental data and with the other calculations wherever available and good agreement is obtained over the energy range 10 ~ 5000 eV. It is shown that the correlated calculations are much closer to the available experimental data than the uncorrelated ones at lower energies, especially below 500 eV. Therefore,considering the overlapping effect of electron clouds in the complex optical model potential could be helpful for the better accuracy of the total cross section calculations of electron scattering from molecules. 展开更多
关键词 total cross section additivity rule atomic and molecular collision
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Total cross sections for electron scattering from sulfur compounds
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作者 谭晓明 王艳文 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第2期218-222,共5页
The original additivity rule method cannot give good results for electron scattering from SO,SO2,SO2Cl2,SO2ClF,and SO2F2 molecules at low energy,because the electron-molecule scattering is simply reduced to electron-a... The original additivity rule method cannot give good results for electron scattering from SO,SO2,SO2Cl2,SO2ClF,and SO2F2 molecules at low energy,because the electron-molecule scattering is simply reduced to electron-atom scattering.Considering the difference between the bound atom in a molecule and the corresponding free atom,the original additivity rule is revised.With the revised additivity rule,the total cross sections for electron scattering from these molecules are calculated over a wide energy range below 3000 eV and compared with the available experimental and theoretical data.A better agreement between them is obtained. 展开更多
关键词 the revised additivity rule total cross sections electron scattering
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Total Cross Sections for Electron Scattering on Polyatomic Molecules (CH4, CO2,NO2, and N2O) at 10~3000 eV
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作者 SUNJin-Feng XUBin +1 位作者 LIUYu-Fang SHIDe-Heng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5期895-899,共5页
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
关键词 total cross section additivity rule optical potential model
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