2MeV/amu裸碳离子碰撞氦离子单电离的全微分截面的结构（英文）

用修饰的库仑波(MCB)模型计算入射能量2MeV/amu裸碳离子碰撞氦单电离的全微分截面,并将计算结果与相应的实验数据和其他理论结果进行比较,发现MCB理论在较小的电离电子能量和较大的动量转移条件下与实验结果符合得很好,在动量转移比较小时MCB理论结果binary峰的位置向大角方向发生了偏移。MCB理论和3CW(三体库仑波)理论相似,他们都比3DW-EIS(三体扭曲波程函初态近似)理论符合的好,说明了在微扰势中被动离子与入射粒子的相互作用是不可忽略的。与3CW理论相比,MCB模型在初态波函数和相互作用势中加入扭曲效应,比较发现扭曲效应会影响全微分截面的大小,但影响不是很明显。     

中高能入射条件下裸碳离子碰撞氦原子单电离的全微分截面

利用四体模型计算了100 和 2 MeV/amu裸碳单电离氦原子的全微分截面,其结果与实验数据和其它理论进行了比较。对于高能入射情况,在散射平面小动量转移和中间动量转移时现在的理论结果和实验符合的很好,然而在大动量转移时和在垂直平面有明显差异。对于低能入射情况,四体结果定性与实验结果一致,而且优于三体扭曲波(3DW-EIS)结果,表明四体效应在低能入射比在高能入射时明显。     

中高能入射条件下裸碳离子碰撞氦原子单电离的全微分截面(英文)

利用四体模型计算了100和2MeV/amu裸碳单电离氦原子的全微分截面,其结果与实验数据和其它理论进行了比较.对于高能入射情况,在散射平面小动量转移和中间动量转移时现在的理论结果和实验符合的很好,然而在大动量转移时和在垂直平面有明显差异.对于低能入射情况,四体结果定性与实验结果一致,而且优于三体扭曲波(3DW-EIS)结果,表明四体效应在低能入射比在高能入射时明显.     

100MeV/amu C6+ 碰撞氦原子单电离的全微分截面

利用修正的库仑玻恩近似理论（MCBPT和MCB）计算了散射平面和垂直平面内100MeV/amu C6+ 单电离氦原子的全微分截面,研究了核核作用对截面的影响.其结果与实验数据和3DW理论进行了比较.发现,对于小动量转移,MCBPT计算结果与实验符合的很好;对于大动量转移,MCB结果很好的反映了实验数据.而且,我们详细的分析了扭曲势效应对截面的影响,结果表明随着动量转移的增加扭曲势效应迅速增强.     

16-MeV O7+碰撞氦原子单电离的全微分截面

考虑核间相互作用,利用修正的库仑玻恩模型(MCB-PT)计算了入射能量为16 MeV 的O7+碰撞氦单电离的全微分截面,并将计算结果与最近的实验数据和三体库仑波(3C)模型及含核间相互作用的连续扭曲波程函初态 (CDW-EIS-PT)模型所得结果进行了比较,发现MCB-PT理论结果在中间动量转移条件下binary峰的位置与实验结果符合得很好,且位于动量转移的方向上。此外,分析了扭曲效应对全微分截面的影响,表明随着动量转移的增加,扭曲效应更加明显。     

16-MeV O7+碰撞氦原子单电离的全微分截面

考虑核间相互作用,利用修正的库仑玻恩模型(MCB-PT)计算了入射能量为16 MeV 的O7+碰撞氦单电离的全微分截面,并将计算结果与最近的实验数据和三体库仑波(3C)模型及含核间相互作用的连续扭曲波程函初态 (CDW-EIS-PT)模型所得结果进行了比较,发现MCB-PT理论结果在中间动量转移条件下binary峰的位置与实验结果符合得很好,且位于动量转移的方向上。此外,分析了扭曲效应对全微分截面的影响,表明随着动量转移的增加,扭曲效应更加明显。     

16 MeV O~(7+)碰撞氦原子单电离的全微分截面（英文）

考虑核间相互作用,利用修正的库仑玻恩(MCB-PT)模型计算了入射能量为16 Me V的O~(7+)碰撞氦单电离的全微分截面,并将计算结果与最近的实验数据和三体库仑波(3C)模型及连续扭曲波程函初态(CDW-EIS)模型所得结果进行了比较,发现MCB-PT理论结果在中间动量转移条件下binary峰的位置与实验结果符合得很好,且位于动量转移的方向上.此外,分析了扭曲效应对全微分截面的影响,表明随着动量转移的增加,扭曲效应更加明显.     

AuQ+碰撞氦原子单电离的全微分截面

利用三体扭曲波计算了3.6 MeV/amu的Au^Q+ (Q=24,53)碰撞氦原子单电离的全微分截面,其结果与实验数据和其它理论进行了比较,表明全微分截面受到高电荷入射粒子的强烈影响,敲出的电子被“拖拽”沿着向前的方向. 但是,所有的理论结果都不能呈现实验上全微分截面的独特的向前峰.     

Fully differential cross sections for C6+ single ionization of helium

The three-Coulomb-wave(3C) model is applied to study the single ionization of helium by 2 MeV/amu C6+ impact.Fully differential cross sections(FDCS) are calculated in the scattering plane and the results are compared with experimental data and other theoretical predictions.It is shown that the 3C results of the recoil peak are in very good agreement with experimental observations,and variation of the position of the binary peak with increasing momentum transfer also conforms better to the experimental results.Furthermore,the contributions of different scattering amplitudes are discussed.It turns out that the cross sections are strongly influenced by the interference of these amplitudes.     

100 MeV/amu C~(6+)碰撞氦原子单电离的全微分截面

利用全量子方法改进且加入核核作用(PT)的修正库仑玻恩近似(MCBPT)和前人基于半经典的方法且不考虑核核作用的修正库仑玻恩近似(MCB)计算了散射平面和垂直平面内100 Me V/amu C6+单电离氦原子的全微分截面,研究了核核作用对截面的影响.其结果与实验数据和3DW理论进行了比较.发现,对于小动量转移,MCBPT计算结果与实验符合的很好;对于大动量转移,MCB结果很好的反映了实验数据.而且,我们详细的分析了扭曲势效应对截面的影响,结果表明随着动量转移的增加扭曲势效应迅速增强.     

Higher Order Multipole Potentials and Electrostatic Screening Effects on Cohesive Energy and Bulk Modulus of Metallic Nanoparticles

Higher order multipole potentials and electrostatic screening effects are introduced to incorporate the dangling bonds on the surface of a metallic nanopaticle and to modify the coulomb like potential energy terms, respectively. The total interaction energy function for any metallic nanoparticle is represented in terms of two- and three-body potentials. The two-body part is described by dipole-dipole interaction potential, and in the
three-body part, triple-dipole (DDD) and dipole-dipole-quadrupole (DDQ) terms are included. The size-dependent cohesive energy and bulk modulus are observed to decrease with decreasing sizes, a result which is in good agreement with the experimental values of Mo and W nanoparticles.     

Polyamide 6/modified Carbon Black Nanocomposites Prepared via In Situ Polymerization

Polyamide 6/modified carbon black (PA6/MCB) composites were prepared via in-situ ring opening polymerization of caprolactam in the presence of dispersed carboxyl group modified carbon black (MCB). The dispersion of MCB in the PA6 matrix, nonisothermal crystallization and melting behaviors, and volume resistivity of the composites were investigated by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and a resistivity meter, respectively. The results indicated that MCB dispersed well in the PA6 matrix. When the MCB content was 5 wt%, the MCB particles were of a nanoscale. The conductivity percolation threshold of the PA6/MCB composites was 8 wt% due to the good dispersion of MCB in the PA6 matrix. The addition of MCB elevated the cold crystallization temperature of PA6, reflecting the effectiveness of MCB as nucleating agents. However, the MCB decreased the crystallization enthalpy of PA6 during both heating and cooling processes.     

Crystallization Behavior of Poly(Lactic Acid) Filled with Modified Carbon Black

A novel method was employed to modify the surface of carbon black (CB) by an organic small molecule in a Haake Rheomix mixer. The modified carbon black (MCB) was dispersed uniformly in poly(lactic acid; PLA). The crystallization behaviors of PLA, PLA/CB and PLA/MCB composites were investigated by differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD), small-angle X-ray scattering (SAXS) and polarizing optical microscopy. It is found that the addition of CB or MCB can influence the crystallization behavior of PLA. PLA/MCB has a faster crystallization rate and higher crystallization peak temperature than PLA/CB. For non-isothermal studies, Jeziorny and Mo equations were employed. The Mo equation can well describe the non-isothermal crystallization of the three samples. For PLA/CB and PLA/MCB composites containing 3wt% fillers, the nucleating activity for CB is about 0.32, and about 0.16 for MCB. All these results show that MCB is an effective nucleating agent. PLA/MCB has a higher nucleation rate than PLA/CB because of the finer dispersed particles size and improved interaction between MCB and PLA.     

Coulomb forces in the three-body problem with application to direct nuclear reactions

Faddeev equations are considered in the case of three charged particles interacting with both separable nuclear two-body interactions and also including Coulomb forces. Modified Faddeev equations with Coulomb Green's functions are introduced. The three-body amplitudes are given into pure Coulomb and distorted-Coulomb amplitudes. Introducing a decomposition in the angular momentum states, a set of three-body integral equations is obtained. The effect of pure coulomb amplitudes is studied in direct nuclear reactions and found to give a large contribution to the cross sections. The three-body integral equations obtained are applied for direct nuclear reactions. The angular distributions for¹²C(⁶Li,d)¹⁶O,¹⁶O(⁶Li,d)²⁰Ne, and¹²C(⁶Li,α)¹⁴N transfer reactions are calculated as well as for the⁶Li elastic scattering on¹²C. From the good agreement between the theoretically calculated and experimental data, better spectroscopic factors are extracted. The effect of including Coulomb forces in the three-body problem is found to improve the results by about 16.26%.     

Variational calculation of some S-states of Coulomb three-body systems

A generalized Hylleraas-type basis set with three nonlinear parameters is proposed to study three-body systems interacting via coulomb forces within the framework of non-relativistic quantum mechanics. This basis set improves the rate of convergence with respect to previous ones, specially for non-symmetric systems and excited states of two electron atoms. Accurate binding energies and other properties for S-states of helium-like ions, muonic molecules and the positronium negative ion are reported. Received 21 July 2000 and Received in final form 4 October 2000     

中子物质中的3PF2态超流性和微观三体核力效应

利用Brueckner-Hartree-Fock(BHF)和BCS理论方法，计算了纯中子物质中处于³PF₂态的中子对关联能隙，特别是研究并讨论了微观三体核力对³PF₂态中子超流性强弱的影响. 结果表明：三体核力显著地增强了中子物质中³PF₂态中子超流性；当采用BHF单粒子能谱时，三体核力导致相应的对关联能隙峰值由0.22MeV增大到0.50MeV. 关键词： 中子物质 3PF₂超流性')" href="#">³PF₂超流性 三体核力 BCS理论     

质子碰撞氦原子单电离全微分截面的后碰撞作用和扭曲效应

用扭曲波方法,推广了修正的库仑波恩（MCB）近似计算到重离子碰撞He原子电离问题计算。检查了对75keV 质子碰撞氦原子单电离的全微分截面的应用情况。结果表明,现在的方法定性地产生了实验的峰结构,尤其是在垂直平面。应用MCB方法研究这一碰撞体系中的后碰撞(PCI)效应,发现PCI效应对全微分截面的形状在散射平面和垂直平面都有着强烈的影响。同时,分析了扭曲效应对全微分截面的贡献。表明,随着动量转移的增加,扭曲效应的作用变得越来越重要。尤其是,扭曲效应定性解释了负角区域的结构。     

质子碰撞氦原子单电离全微分截面的后碰撞作用和扭曲效应

用扭曲波方法,推广了修正的库仑波恩（MCB）近似计算到重离子碰撞He原子电离问题计算。检查了对75keV 质子碰撞氦原子单电离的全微分截面的应用情况。结果表明,现在的方法定性地产生了实验的峰结构,尤其是在垂直平面。应用MCB方法研究这一碰撞体系中的后碰撞(PCI)效应,发现PCI效应对全微分截面的形状在散射平面和垂直平面都有着强烈的影响。同时,分析了扭曲效应对全微分截面的贡献。表明,随着动量转移的增加,扭曲效应的作用变得越来越重要。尤其是,扭曲效应定性解释了负角区域的结构。     

Electrical Conductivity of Nonideal Plasma

The electrical conductivity of fully ionized moderately nonideal plasmas with coulomb interaction parameters 0.1 < ? ? 1 where ? = Ze2n1/3/KT is the ratio of coulomb and thermal energies is calculated for displaced Maxwell and Fermi electron distributions, respectively. The electrons are scattered by an effective coulomb potential ?(r) = Zer-1 exp (-r/?) which considers binary (0 < r < ?) and many-body (? < r < ?) interactions. The shielding distance is given by ? = ?(4?n/3Z)-1/3 with ? = ?0?-N ~ 1 for classical plasmas and ? = ?(4?n/3Z)-1/3 with ? = ?0?-N?-M ~ 1 for quantum plasmas, where ? = Ze2n1/3/h2 m-1n2/3 is the ratio of coulomb interaction and quantum potential energies of the electrons. It is shown that the resulting conductivity formulas are applicable to densities up to four orders of magnitude higher than those of the ideal conductivity theory, which breaks down at higher densities because the Debye radius loses its physical meaning as a shielding length and upper impact parameter.     

Ni^2＋：LiNbO3的光学吸收谱和EPR的研究

应用三角晶场中d^2(d^8)电子组态的包括静电相互作用和自旋－轨道耦合相综合利用物强场能量矩阵,采用完全对角化方法,精确地计算了具有C3V对称的Ni^2 :LiNbO3的光学吸收谱和EPR谱。理论结果与实验值符合得很好。