植物多酚的抗辐射作用

Plant polyphenols that consist of flavonoids, tannins, phenolic acids and anthocyanin are widely found in types of plants in their hulls, xylem, leaves, roots and fruits. Plant polyphenols containing more than one phenolic hydroxyl show diverse biological activities such as antioxidation, free radical scavenging and bacteriostasis. Plant polyphenols can offer protons as hydrogen donator to react with the free radicals to scavenge them, hence it can alleviate the damages of macromolecule, cells and tissues due to radiation and free radicals. This paper reviewed the previous reports about the plant polyphenols that were used in radiation protection.植物多酚是指植物中化学分子结构含有多个酚性羟基的成分，广泛存在于植物的皮、木、叶、根、果实等中，包括黄酮类、鞣质类、酚酸类以及花色苷类等。植物多酚有较强的抗氧化作用，可消除机体内过量的自由基，从而减轻自由基对DNA和蛋白质等机体大分子的损伤，对机体细胞和组织具有保护作用。本文对近年来用于辐射损伤防护的植物多酚类物质进行了归类讨论

Thermal Conductance for Single Wall Carbon Nanotubes

We report a theoretical analysis of the phonon thermal conductance, \kappa (T), for single wall carbon nanotubes (SWCN). In a range of low temperatues up to 100K, \kappa (T) of perfect SWCN is found to increase with temperature, approximately, in a parabolic fashion. This is qualitatively consistent with recent experimental measurements where the tube-tube interactions are negligibly weak. When the carbon-carbon bond length is slightly varied, \kappa (T) is found to be qualitatively unaltered which implies that the anharmonic effect does not change the qualitative behavior of \kappa (T).Comment: Revtex, 4 figure

Constructing minimal telescopers for rational functions in three discrete variables

We present a new algorithm for constructing minimal telescopers for rational functions in three discrete variables. This is the first discrete reduction-based algorithm that goes beyond the bivariate case. The termination of the algorithm is guaranteed by a known existence criterion of telescopers. Our approach has the important feature that it avoids the potentially costly computation of certificates. Computational experiments are also provided so as to illustrate the efficiency of our approach

Phase diagram and exotic spin-spin correlations of anisotropic Ising model on the Sierpi\'nski gasket

The anisotropic antiferromagnetic Ising model on the fractal Sierpi\'{n}ski gasket is intensively studied, and a number of exotic properties are disclosed. The ground state phase diagram in the plane of magnetic field-interaction of the system is obtained. The thermodynamic properties of the three plateau phases are probed by exploring the temperature-dependence of magnetization, specific heat, susceptibility and spin-spin correlations. No phase transitions are observed in this model. In the absence of a magnetic field, the unusual temperature dependence of the spin correlation length is obtained with $0 \leq$J$_b/$J$_a<1$, and an interesting crossover behavior between different phases at J$_b/$J$_a=1$ is unveiled, whose dynamics can be described by the J$_b/$J$_a$-dependence of the specific heat, susceptibility and spin correlation functions. The exotic spin-spin correlation patterns that share the same special rotational symmetry as that of the Sierpi\'{n}ski gasket are obtained in both the $1/3$ plateau disordered phase and the $5/9$ plateau partially ordered ferrimagnetic phase. Moreover, a quantum scheme is formulated to study the thermodynamics of the fractal Sierpi\'{n}ski gasket with Heisenberg interactions. We find that the unusual temperature dependence of the correlation length remains intact in a small quantum fluctuation.Comment: 9 pages, 12 figure