Factors that influence the extraction of polycyclic aromatic hydrocarbons from coal

IEECAS SKLLQG

岭南东江流域晚更新世哺乳动物化石的新发现

IEECAS SKLLQG

西安地区人工林土壤干层与水分恢复研究

IEECAS SKLLQG

~(146)Tb的能级结构研究

利用能量为161—175MeV的~(32)S束流,通过反应~(118)Sn(~(32)S,1p3n)~(146)Tb研究了双奇核~(146)Tb的高自旋态能级结构。实验进行了γ射线的激发函数、γ射线的各向异性度、X-γ和γ-γ-t符合测量。基于这些测量结果,建立了激发能达8390kev的~(146)Tb核的能级纲图,其中包括新发现的41条γ射线和新建立的27个能级,并指定了~(146)Tb新发现能级的自旋值。用一个h_(11/2)价质子和一个h_(11/2)~(-1)价中子空穴耦合、πh_(11/2)υh_(11/2)~(-1)与~(146)Gd核实激发态的耦合对~(146)Tb的能级结构进行了定性地讨论。

Properties of the beta-delayed proton decay of Ho-146

The proton-rich isotope Ho-148 was produced via the fusion-evaporation reaction Mo-92 (Ni-58, 3p1n). The beta-delayed proton decay of Ho-146 was studied by proton-gamma coincidence measurements using a He-jet tape transport system. The gamma-transitions in Tb-145 following the proton emissions were observed, and the beta-delayed proton branching ratios to the final states in the grand-daughter nucleus Tb-145 were determined. According to the relative branching ratios, the ground-state spin of Ho-146 has been proposed and the possible configuration discussed.

3D Anisotropic Elastoplastic-Damage Model and its Application in Simulating the Behavior of Rock Materials

A 3D anisotropic elastoplastic-damage model was presented based on continuum damage mechanics theory. In this model, the tensor decomposition technique is employed. Combined with the plastic yield rule and damage evolution, the stress tensor in incremental format is obtained. The derivate eigenmodes in the proposed model are assumed to be related with the uniaxial behavior of the rock material. Each eigenmode has a corresponding damage variable due to the fact that damage is a function of the magnitude of the eigenstrain. Within an eigenmodes, different damage evolution can be used for tensile and compressive loadings. This model was also developed into finite element code in explicit format, and the code was integrated into the well-known computational environment ABAQUS using the ABAQUS/Explicit Solver. Numerical simulation of an uniaxial compressive test for a rock sample is used to examine the performance of the proposed model, and the progressive failure process of the rock sample is unveiled.

固体破坏的损伤演化诱致突变现象

介绍了基于细观非线性动力学模型的研究所取得的进展。发现系统显示一种共性特征，称为演化诱致突变，即演化模式从整体稳定向灾变性模式转变，宏观破坏的样本个性行为，以及宏观性质对细观无序性的敏感性。