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Reaction pathway analysis was carried out to investigate the activation energy barriers of Shockley partial dislocation mobility in 3C-SiC. For each partial dislocation, there are two types of dislocations according to which kind of atom, Si or C, comprises the core edge of the dislocation line. In this paper, the partial dislocation is simulated by Vashishta potential functions. Moreover, the activation energy of kink pair nucleation and kink migration are investigated by reaction pathway analysis. The dependence of the activation energy on the driving shear stress is also discussed. The results show that during kink migration, 30° partial dislocations have a lower activation energy barrier than 90° partial dislocation. And, C-core partial dislocations have a higher activation energy barrier than Si-core dislocations for both degrees of partial dislocations during kink migration and nucleation. This conclusion is consistent with the experimental result that Si-core dislocations migrate more readily than C-core dislocations. Furthermore, we found that partial dislocations with larger distance between the dangling bond atoms along the dislocation line have higher activation energy barriers. Based our calculation results, we propose new models to account for the morphological differences in the dislocation lines.

The Caspian Sea has a unique ecosystem that consists of endemic species. The deterioration of the unique ecosystem has become increasingly worrisome since a wide variety of pollutants have been released into the water. Water circulation plays a key role in advection and diffusion of these pollutants. In the present study, water circulation and thermohaline structures in the Caspian Sea were analyzed by means of a three dimensional numerical simulation. The effects of meteorological changes, river inflow, and an icing event were taken into account as boundary conditions. Numerical simulation was carried out for 20 years to achieve stable seasonal variations in model variables. As a result, the horizontal distributions of water temperature and salinity could be reproduced; the gradient of water temperature in the northsouth direction, the decrease in water temperature along the east coast of the middle Caspian Sea due to coastal upwelling, and low salinity in the northern Caspian Sea. The icing event kept the water temperature in the northern Caspian Sea from decreasing to an unrealistic value. The observed cyclonic gyres were basically formed by the density-driven current due to thermohaline structure.

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Node importance ranking of complex networks is of great significance to the study of network robustness. The classical centrality measure degree can reflect the number of neighbors of a node, but it ignores the information between its neighbors. In order to mine the important nodes in the network accurately and efficiently, a method of ranking the node importance of complex networks based on multiattribute evaluation and node deletion is proposed in this paper. Based on the degree attributes of the target node and its neighbors, this method introduces two attributes, which are the local network density centered on the target node and the assortativity coefficient. It takes into account the characteristics of the scale, tightness, and topology of the local area network where the node and its neighbors are located. This paper conducts deliberate attack experiments on four real networks. Through a comparison between the experimental results of the maximal connected coefficient and network efficiency, our approach is proven to be valid and feasible.

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