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1.
In this paper, we investigate two classes of quasi-linear multi-point boundary value problems with sign-changing nonlinearity. By applications of fixed point index theory, sufficient conditions for the existence of twin positive solutions are established.  相似文献   
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《Physics letters. A》2006,357(6):449-453
By viewing the non-equilibrium transport setup as a quantum open system, we propose a reduced-density-matrix based quantum transport formalism. At the level of self-consistent Born approximation, it can precisely account for the correlation between tunneling and the system internal many-body interaction, leading to certain novel behavior such as the non-equilibrium Kondo effect. It also opens a new way to construct time-dependent density functional theory for transport through large-scale complex systems.  相似文献   
4.
《Physics letters. A》2006,360(2):380-383
One-dimensional dihalide-bridged polymer Co(thiazole)2Cl2 has been studied with the self-consistent full-potential linearized augmented plane wave method (FP_LAPW) based on the density functional theory (DFT). Spin distributions in ferromagnetic and antiferromagnetic states of it have been obtained by the calculation. The electronic structure and magnetic coupling between tow cobalt (II) ions along chain are discussed.  相似文献   
5.
《Physics letters. A》2006,349(6):462-466
Many social, technological, biological and economical systems are best described by evolved network models. In this short Letter, we propose and study a new evolving network model. The model is based on the new concept of neighbourhood connectivity, which exists in many physical complex networks. The statistical properties and dynamics of the proposed model is analytically studied and compared with those of Barabási–Albert scale-free model. Numerical simulations indicate that this network model yields a transition between power-law and exponential scaling, while the Barabási–Albert scale-free model is only one of its special (limiting) cases. Particularly, this model can be used to enhance the evolving mechanism of complex networks in the real world, such as some social networks development.  相似文献   
6.
Golub et al. (2001, BIT, 41, 71–85) gave a generalizedsuccessive over-relaxation method for the augmented systems.In this paper, the connection between the SOR-like method andthe preconditioned conjugate gradient (PCG) method for the augmentedsystems is investigated. It is shown that the PCG method isat least as accurate (fast) as the SOR-like method. Numericalexamples demonstrate that the PCG method is much faster thanthe SOR-like method.  相似文献   
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Positron annihilation lifetime spectroscopy (PALS) based on a pulsed slow positron beam was applied to study mesoporous silica films, synthesized using amphiphilic PEO–PPO–PEO triblock copolymers as structure-directing agents. The pore size depends on the loading of different templates. Larger pores were formed in silica films templated by copolymers with higher molecular-weights. Using 2-dimensional PALS, open porosity of silica films was also found to be influenced by the molecular-weight as well as the ratio of hydrophobic PPO moiety of the templates.  相似文献   
9.
Using the method of diagonalization, in which zero-field wavefunctions from a potential model are chosen as a basis, we calculate positions and widths of anticrossings for highly excited Stark states of Rb with principal quantum number n up to 49. We obtain the theoretical positions and widths in good agreement with available experimental values, and we present scaling laws of the field positions and widths of anticrossings that can be used to provide information for future experiments.  相似文献   
10.
Biosorption of 241Am by a fungus A. niger, including the spore and hyphae, was investigated. The preliminary results showed that the adsorption of 241Am by the microorganism was efficient. More than 96% of the total 241Am could be removed from 241Am solutions of 5.6-111 MBq/l (C o) by spore and hyphaeof A. niger, with adsorbed 241Am metal (Q) of 7.2-142.4 MBq/g biomass, and 5.2-106.5 MBq/g, respectively. The biosorption equilibrium was achieved within 1 hour and the optimum pH range was pH 1-3. No obvious effects on 241Am adsorption by the fungus were observed at 10-45 °C, or in solutions containing Au3+ or Ag+, even 2000 times above the 241Am concentration. The 241Am biosorption by the fungus obeys the Freundlich adsorption equation. There was no significant difference between the adsorption behavior of A. nigerspore and hyphae. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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