细胞悬浮液介电谱检测与应用研究进展

细胞悬浮液介电谱是一种快速、实时、无损进行细胞物理特性定量研究的方法,在研究细胞构成和细胞生命活动过程中具有重要意义。细胞的结构和组成使其成为介电谱研究最适合的体系之一。细胞悬浮液介电谱随着检测频率的增加呈现α、β和γ三个典型的弛豫,对弛豫类型的解析有助于了解细胞组分和活动的信息。而细胞电参数模型的发展将细胞介电特性的研究深化到亚细胞层面,有助于了解更加细致的细胞组分和生命活动的信息。本文对细胞的介电行为,细胞悬浮液介电谱的检测、解析以及应用进行简要综述。

Research on the Fragment Impact Resistance of a Composite Mast

Due to the unique structural mode and material property of a composite sandwich plate, related research such as fragment impact resistance of a composite mast is short of publication and urgent in this field. In this paper, the commonly accepted sandwich core board theory was modified. Damage caused by a fragment attack was simulated onto a sandwich plate model built with solid and shell elements. It was shown that shear failure and vast matrix cracking are the main reasons for outer coat damage, and tension failure and partial matrix cracking are the cause for inner coat damage. Additionally, according to complexities in actual sea battles, different work conditions of missile attacks were set. Ballistic limit values of different fragment sizes were also obtained, which provides references for enhancing the fragment impact resistance of a composite mast.

A Shell Model Mass Formula for Exotic Light Nuclei

An analytic phenomenological shell model mass formula for light nuclei is constructed. The formula takes into account the non locality of the self consistent single particle potential and the special features of light nuclei, namely： （a） charge and mass distributions are closer to a Gaussian shape than to the shape characteristic in medium and heavy nuclei; （b） the central charge and mass densities are larger than, and decrease towards, the ＂asymptotic＂ values that are the reference parameters for nuclear matter; and （c） after a shell closure, the next level has a larger orbital angular momentum and a noticeably larger mean square radius. Only then a good numerical fit is obtained with parameters consistent with optical model analysis and empirical spin-orbit couplings. A correlation between the ＂skin effect＂ and the symmetry dependence of the optical potential is established. Towards the neutron drip line the potential well depth, the spin-orbit splitting of the single particle levels and the gap between major shells decrease, as has been observed. The ensuing shift and contraction of the single particle level scheme may lead to： （a） to strong configuration mixing and new magic numbers, and （b） the onset of the halo effect, to avoid the expulsion of single particle levels to the continuum.

Healing Temperature of Hybrid Structures Based on Genetic Algorithm

The healing temperature of suspen-dome with stacked arches(SDSA)and arch-supported single-layer lattice shell structures was investigated based on the genetic algorithm. The temperature field of arch under solar radiation was derived by FLUENT to investigate the influence of solar radiation on the determination of the healing temperature. Moreover, a multi-scale model was established to apply the complex temperature field under solar radiation. The change in the mechanical response of these two kinds of structures with the healing temperature was discussed. It can be concluded that solar radiation has great influence on the healing temperature, and the genetic algorithm can be effectively used in the optimization of the healing temperature for hybrid structures.

Modeling stationary and moving cracks in shells by X-FEM with CB shell elements

The continuum-based(CB)shell theory is combined with the extended finite element method(X-FEM)in this paper to model crack propagation in shells under static and dynamic situations.Both jump function and asymptotic crack tip solution are adopted for describing the discontinuity and singularity of the crack in shells.Level set method(LSM)is used to represent the crack surface and define the enriched shape functions.Stress intensity factors(SIFs)are calculated by the displacement interpolation technique to prove the capability of the method and the maximum strain is applied for the fracture criterion.Also,an efficient integration scheme for the CB shell element with cracks is proposed.

Analytical Derivations of Single-Particle Matrix Elements in Nuclear Shell Model

We present analytical method to calculate single particle matrix elements used in atomic and nuclear physics. We show seven different formulas of matrix elements of the operator f(r)d_r^m where f(r) = r~μ, r~μjJ(qr), V(r)corresponding to the Gaussian and the Yukawa potentials used in nuclear shell models and nuclear structure. In addition,we take into account a general integral formula of the matrix element 〈 n′ l′|f(r) d_r^(m) |n l〉 that covers all seven matrix elements obtained analytically.