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141.
This paper recalls the formalism of H. J. Leisi, which shows an alternative way to understand Perturbed Angular Correlation
Spectroscopy: as a quantum interference effect.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
142.
Light charged particles emitted in heavy-ion induced reactions, their spectra and angular distributions measured over a range
of energies, carry the signature of the underlying reaction mechanisms. Analysis of data of light charged particles, both
inclusive and exclusive measured in coincidence with gamma rays, fission products, evaporation residues have yielded interesting
results which bring out the influence of nuclear structure, nuclear mean field and dynamics on the emission of these particles. 相似文献
143.
F.S.V. Bazn 《Applied mathematics and computation》2008,200(2):537
A method for computing highly accurate numerical solutions of 1D convection–diffusion equations is proposed. In this method, the equation is first discretized with respect to the spatial variable, transforming the original problem into a set of ordinary differential equations, and then the resulting system is integrated in time by the fourth-order Runge–Kutta method. Spatial discretization is done by using the Chebyshev pseudospectral collocation method. Before describing the method, we review a finite difference-based method by Salkuyeh [D. Khojasteh Salkuyeh, On the finite difference approximation to the convection–diffusion equation, Appl. Math. Comput. 179 (2006) 79–86], and, contrary to the proposal of the author, we show that this method is not suitable for problems involving time dependent boundary conditions, which calls for revision. Stability analysis based on pseudoeigenvalues to determine the maximum time step for the proposed method is also carried out. Superiority of the proposed method over a revised version of Salkuyeh’s method is verified by numerical examples. 相似文献
144.
研究谐振子势与高斯势联合势阱中玻色爱因斯坦凝聚体的基态。发现凝聚体形成巨涡旋时,其涡旋个数等于平均角动量,且凝聚体密度分布和角动量密度分布相同,进而得到凝聚体形成巨涡旋时所处基态是角动量的本征态。发现势阱从各向同性的环形势阱逐渐变为各向异性的环形势阱的过程中,凝聚体的平均角动量与涡旋个数之比先由1平缓下降,然后迅速下降,最后保持在0.5附近。同时给出凝聚体密度分布和角动量分布的特征,并作出相应解释。 相似文献
145.
Based on the beyond-mean-field Skyrme–Hartree–Fock model, impurity effects of the Λhyperon in the hypernuclear systems ${}_{\,{\rm{\Lambda }}}^{25}$ Mg and ${}_{\,{\rm{\Lambda }}}^{29}$ Si are investigated, respectively. Four cases, in which the Λhyperon occupies the single-particle orbitals ${\rm{\Lambda }}$[000]${\tfrac{1}{2}}^{+}$, ${\rm{\Lambda }}$[110]${\tfrac{1}{2}}^{-}$, ${\rm{\Lambda }}$[101]${\tfrac{3}{2}}^{-}$ and ${\rm{\Lambda }}$[101]${\tfrac{1}{2}}^{-}$, are focused. In each case, the potential energy surface and the energy curves projected on certain angular momenta are employed to show the influence of the Λhyperon on the nuclear core. Beside the shrinkage effect that is induced by the Λhyperon occupying the sΛ orbital, it is found that the Λhyperon on the pΛ orbital, ${\rm{\Lambda }}$[110]${\tfrac{1}{2}}^{-}$, drives the nuclear core toward a prolate shape, while the ones on the other two pΛ orbitals, ${\rm{\Lambda }}$[101]${\tfrac{3}{2}}^{-}$ and ${\rm{\Lambda }}$[101]${\tfrac{1}{2}}^{-}$, drive the nuclear core toward an oblate shape. The energy spectra and the corresponding intra-band E2 transition rates for the rotational bands are given as a prediction for future experiments. 相似文献
146.
147.
148.
三马山小区巴东组三段泥质灰岩由于岩溶溶蚀作用已全部发生了变形 ,根据变形程度的差别 ,可将变形区分为三个地带 ,即上部轻度溶蚀沉降地带 (Ⅰ ) ,中部溶蚀沉降地带 (Ⅱ )和下部沿江滑坡 (Ⅲ )。建筑设施主要分布在中部溶蚀沉降地带 ,应注意防水。下部沿江滑坡治理难度大 ,不适于移民迁建。 相似文献
149.
基于弹塑性力学和损伤理论,建立了一个与应力球张量有关的具损伤正交各向异性材料的混合硬化屈服准则,该准则无量纲化后与各向同性材料的Mises准则同构,在此基础上,建立了正交各向异性材料的增量型和全量型弹塑性损伤本构方程,并以具确定弱区域正交各向异性矩形薄板为例,根据屈曲时的能量准则和全量理论,以等效塑性应变为内变量,对其弹塑性屈曲问题进行了分析,讨论了几何参数和弱区域对正交各向异性薄板弹塑性屈曲临界应力的影响. 相似文献
150.
The steady-state conjugated turbulent heat transfer with axial conduction in the wall and convection boundary conditions is solved with the generalized integral transform technique for the flow of Newtonian fluid in parallel-plate duct. A lumped wall model that neglects transverse temperature gradients in the solid but that takes into account the axial heat conduction along the wall is adopted. Highly accurate results are presented for the fluid bulk and wall temperatures and Nusselt number. The effects of the conjugation parameter, Biot number, and the dimensionless channel length on Nusselt number and fluid bulk and wall temperatures are systematically investigated. 相似文献