作者机构：
[徐志峰] Physics and Information Sciences College, Hunan Normal University, Changsha 410081, China;[徐志峰; 周光辉] Department of Physics, Hunan City College, Yiyang 413000, China
期刊：
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS,2004年222(1-2):44-52 ISSN：0168-583X
通讯作者：
Fan, S
作者机构：
Inst Atom Energy, China Nucl Data Ctr, Beijing 102413, Peoples R China.;Shanghai Univ, Shanghai Appl Radiat Inst, Shanghai 201800, Peoples R China.;Hunan City Univ, Dept Phys, Yiyang 413000, Peoples R China.;NW Univ Xian, Dept Phys, Xian 710006, Peoples R China.;[Fan, S] Inst Atom Energy, China Nucl Data Ctr, POB 275,41, Beijing 102413, Peoples R China.
通讯机构：
[Fan, S] I;Inst Atom Energy, China Nucl Data Ctr, POB 275,41, Beijing 102413, Peoples R China.
摘要：
The Second Virial Coefficient of a Classical Mixed GasAbstract:In this paper,canonical ensemble theory is applied to investigate the second Virial coefficient of a classical mixed gas and the limitative expression of the second Virial coefficient formula is discussed;in the meantime, the application of the investigation conclusion is put out.
作者机构：
[李天然] Department of Mathematics, Hunan City College, Yiyang, 413000, China;[陈传淼] Institute of Computation, Hunan Normal University, Changsha, 410081, China
期刊：
Nuclear Science and Engineering,2004年147(1):63-72 ISSN：0029-5639
通讯作者：
Fan, S
作者机构：
[Fan, S] Inst Atom Energy, Beijing 102413, Peoples R China.;Shanghai Univ, Shanghai Appl Radiat Inst, Shanghai 201800, Peoples R China.;Hunan City Univ, Dept Phys, Yiyang 413049, Peoples R China.;N China Elect Power Univ, Beijing 102206, Peoples R China.;NW Univ Xian, Dept Phys, Xian 710006, Peoples R China.
通讯机构：
[Fan, S] I;Inst Atom Energy, Beijing 102413, Peoples R China.
摘要：
To simplify the calculation, some assumptions are considered in the current work. The preequilibrium emission in the first step in the equilibrium process, which is characterized by exciton n = 3 and "never come back, " is considered in the preequilibrium emission process; the alpha emission is only completed with the neutron and proton emission, and the second particle emission is neglected. Under those assumptions, a semiempirical systematics of the cross section for the (n, a) reaction is obtained on the basis of the evaporation and exciton models for the energies ranging up to 20 Me V Within the nuclide mass region of 23 less than or equal to A < 209, a strong dependence on (N - Z + 1)/A and the incident neutron has been observed. The predictions of the semiempirical systematics with the global parameter of the excitation functions for the (n,alpha) reaction are in good agreement with the experimental data.
