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We have synthesized a new series of layered oxyselenides La2O3(Mn1−xCox)2Se2 through a solid state reaction method. Their structure and physical properties were studied through powder X-ray diffraction, electric transport measurements, absorption spectroscopy, bulk magnetization and specific heat experiments. These compounds crystallize in layered structures with the space group I4/mmm. All the samples present semiconducting or insulating behavior with the activation energy ranging from 0.134 eV to 0.400 eV. The ferromagnetic (FM) component is induced as Co enters the lattice, and the FM component raises to its maximum when x is 0.6. The competing of FM and antiferromagnetic (AFM) components led to the emergence of a spin-glass like behavior in the intermediate alloys.

Using a modified dynamic Monte Carlo renormalization group method, the two- dimensional kinetic Ising model is studied, and the dynamic critical exponent is obtained. The critical temperature of phase transition can be obtained by the renormalization method for the correlation function. In the method we used, the correlation function is replaced with the absolute value of the magnetization, and it is found that the evolution of the absolute value of the magnetization over time satisfies the power-law form. It is found that the value of the dynamic critical exponent tends to be a stable value in the form of a power-law function as the scale of the system increases. The dynamic critical exponent obtained is z ≃ 2 . 15 . When the modified dynamic Monte Carlo renormalization group method is applied to the two-dimensional Glauber model, the obtained dynamic critical exponent is z ≃ 2 . 25 .

We investigated the physical properties of the cobalt doped layered oxyselenides BiCu1-xCoxSeO. 5% Co doping led to a large increase in the Seebeck coefficient which should be attributed to the magnetic interactions with the magnetic moment carried by Co atoms. The carrier-type of the material is changed from p-type to n-type with 20% Co doping. We studied the thermoelectric property of Bi0.95Ca0.05Cu0.95Co0.05SeO. The dual-doping sample exhibits higher Seebeck coefficient than Ca single doped sample and the ZT was enhanced remarkably. A maximum ZT value of 0.11 was achieved for Bi0.95Ca0.05Cu0.95Co0.05SeO at 300 K.

In this article, we construct a triangle-growing network with tunable clusters and study the social balance dynamics in this network. The built network, which could reflect more features of real communities, has more triangle relations than the ordinary random-growing network. Then we apply the local triad social dynamics to the built network. The effects of the different cluster coefficients and the initial states to the final stationary states are discussed. Some new features of the sparse networks are found as well.

In this paper, we provide a new approach to create weighted scale-free networks by the method of weight redistribution. In our model, from an Erdös and Rényi random graph, with every edge having the same weight one, along with the total number of vertices and the total weight of all edges constant, we redistribute the weight based on our rules. When the network is dynamically stabilized, we find that both the degree and the strength distributions of our model satisfy the power-law form respectively, with the exponents approximating one. To have the power-law exponents tunable, we give each vertex an intrinsic strength initially. When the improved model is dynamically stabilized, we find the power-law exponents become tunable. Numerical results verify our theoretical analysis.

Based on the field-bus technology and combined with the industrial control products, the intelligent power distribution system in box-type substation was investigated. The scheme model for the intelligent power distribution system was constructed using the field-bus technology. The hardware used in the intelligent power distribution system was presented. The intelligent power distribution system presented in this paper improved the technology of the equipment in box-type substation. The stability and reliability of the box-type substation products were enhanced greatly, which satisfied the users.

A node model is proposed to study the self-organized criticality in the small-world networks which represent the social networks. Based on the node model and the social balance dynamics, the social networks are mapped to the thermodynamic systems and the phenomena are studied with physical methods. It is found that the avalanche in the small-world networks at the critical state satisfies the power-law distribution spatially and temporally.