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In the frame work of chiral perturbation theory, a modified effective Lagrangian for meson-baryon system is constructed, where the SU(3) breaking effect for meson is considered. The difference between physical and chiral limit decay constants is taken into account. Calculated to one loop at O(p3), the sigma terms and strangeness contents of baryon octet are obtained.

Assuming that the recently theta(+) and other exotic resonances belong to the pentaquark (1) over bar(0) over bar of SU(3)(f) with J(P) = 1/2, we constructed a relativistic effective lagrangian in the frame work of baryon chiral perturbation theory. The masses of pentaquarks under isospin symmetry is determined by calculating the propagator to one loop, where the extended on-mass-shell renormalization scheme is applied. Using the experimental data for masses of (+theta), Xi and N, we estimated the mass of Sigma and the sigma terms.

Based on the theory of conservation of momentum, a theoretical method of calculating the shock pressure induced by laser loading via diagnosing plasma recoil momentum is presented. When a high-power laser irradiates a solid target surface, the plasma jet with high velocity induced by laser has a recoil effect on the target. Then the plasma recoil momentum induced by laser irradiating solid target can be calculated by the distribution of electron plasma. At the same time, the subcritical electron plasma density could be measured by interferometry and the supercritical plasma density could be fitted into exponential function form. So the variation of shock wave pressure could be calculated via diagnosing plasma recoil momentum. This method does not consider the relationship between D and u, nor uses the window material nor needs the steady shock propagation. It is a useful method of studying the material property under high strain rate and isentropic compression. Numerical simulation results using one-dimensional radiation hydro code called MULTI for laser intensities ranging from 51012 W/cm2 to 51013 W/cm2 are presented. The electron temperature is nearly equal to the ion temperature for the laser pulse duration 2 ns but much greater than the ion temperature for = 1 ns. This means for that ns pulse duration, the difference between electron and ion temperature could be ignored in general. And in order to fit the shock pressure value more exactly, the density of ablation surface nabl = n0exp(-1) is used in the simulations. The simulation results indicate that the value of calculating shock pressure obtained via diagnosing plasma recoil momentum is similar to the shock pressure calculated by MULTI simulation for ns pulse duration. And the value of calculating shock pressure is also similar to the experimental value for pulse duration = 5 ns. From the simulation results, it is obvious that the method of calculating the shock pressure via diagnosing plasma recoil momentum is effective and feasible.

The research about multiple middle agents chiefly focus on a variety of different architectures to increase system flexibility nowadays, but the optimal design to the architecture is very rare. This paper proposed a optimal logical ring architecture of multiple middle agents in multi-agent systems, according to probability theory, the system are simplified by reducing the numbers of middle agents under the condition of the system is not broken down with definite probability. The optimization results show that the stability and flexibility of the system don't decrease although reducing the number of middle agents, moreover, middle agents can accomplish more tasks in the logical ring. Analysis results show that the presented method is effective and feasible.

The thermal properties of cold dense nuclear matter are investigated with chiral perturbation theory. The evolution curves for the baryon number density, baryon number susceptibility, pressure and the equation of state are obtained. The chiral condensate is calculated and our result shows that when the baryon chemical potential goes beyond $1150 \mathrm{MeV}$, the absolute value of the quark condensate decreases rapidly, which indicates a tendency of chiral restoration., Comment: 17 pages, 9 figures, revtex4

The effect of Sb doping on thermoelectric transport properties of N-type half-Heusler compounds Zr0.25Hf0.25Ti0.5NiSn1-xSbx (x=0, 0.002, 0.005, 0.01, 0.02, 0.03) was studied. Results show that with increasing Sb doping amount, the carrier concentration of the samples increases while the electrical resistivity decreases, especially sharply at low temperature range (~300 K). The Seebeck coefficient decreases, and the temperatures at which the Seebeck coefficient reaches climax move to higher ones. Therefore, the power factor increases by ~20%. The total thermal conductivity increases mainly due to the enhancement of electrical thermal conductivity, the lattice thermal conductivity remains almost unchanged. For the samples with x