Reported here are the results of point-contact electron-tunneling measurements in the high-T, superconductors YBa2Cu307 z and T12Ba&Ca2Cu3OIO+g. The ratio 2A/kT, is 4.0 -5.8 {probability maximum near 4.8) for Y-Ba-Cu-0 and 4.6 for Tl-Ba-Ca-Cu-O. Both are consistent with strongcoupling superconductivity.The measurements at 600 different locations of the same sample of YBa&Cu307 -$ were performed. The energy distribution of energy gaps with the regularity of the ratio 1:3:5reported by Kirk et al. have not been seen in our experiment.

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Bicrystalline ZnO nanocombs have been prepared by zinc powder evaporation proces s at 650℃. The structure of bicrystalline ZnO nanocombs was characterized by XR D, HTEM, SAD, etc., which indicate that the as-synthesized sample are composed of two crystals that form a twin structure parallel to the (1 1 3) plane with th e growth direction of the branching nanowires and the main stems closely paralle l to〈0 0 0 1〉 and〈0 1 1 0〉，respectively. Due to the unique twin structures, both sides of the main stems could be Zn-terminated ZnO (0 0 0 1) polar surface s, which are chemically active. Therefore the aligned branching nanowires can be grown from both sides of the main stems, which is consistent with the structure of the bicrystalline nanomaterials we have obtained. The growth of bicrystallin e ZnO nanocombs bears direct evidence to the polar-surface dominated growth mech anism of the ZnO nanomaterials.

With the rapid development of science and technology, simulation has become an indispensable means to study the laws of objective things. This paper introduces the concept, method and challenge of system simulation. The key of modeling in system simulation is put forward. Finally, the common modeling methods of information systems are introduced, and the advantages and disadvantages of different modeling methods and applications are compared and analyzed.