Possible periodic structures resulting from three-dimensional Penrose tiling (3DPT) by introducing the so-called phason strain are studied. Only two types of cubic structures, simple cubic (sc) and body centered cubic (bcc), are possible. Numbers of the unit-cells, which are the same as those of the 3DPT, within each structure matrix of the sc/bcc structure are also given.

With a 30keV mini-separator at the accelerator laboratory of Fudan University, we have successfully obtained about 1 nA fullerene ion beam. Under the same conditions, we have also observed the fragment ions C⁺_n (n=20-40). The C⁺₆₀(C⁺₇₀) beams will be used study collision between fullerene and electrons, atoms and photons.

It is shown that the supersymmetry breaking can be realized dynamically by Nambu-Jona-Lasinio (NJL) mechanism. The supersymmetry behavior at finite temperature is also investigated and shown that the supersymmetry broken dynamically at zero temperature can be restored at finite temperature.

Using a Q-Q poteiitia1 with the color screening effect due to the creation of light quark pairs, the spectra of bb and cc systems are calculated. An improved fit for the masses of the lightly excited states can be obtained. In particular, the ψ(4160) might be assigned as the 4.5 cc state.

New calculations for the total reaction cross sections and production cross sections of the energetic particles are carried out via the nuclear transport theory. The experimental total reaction cross sections can be reproduced. In addition, the effects of some ingredients 011 the total reaction cross sections can be easily analyzed. It is found that the total reaction cross sections are sensitive to the nuclear equation of state below 100MeV/u and the in-medium nucleon-nucleon cross section in the full energy range addressed. While the π - meson production cross sections can be also calculated.

The experimental data of proton and pion rapidity distributions and proton transverse mass distribution in reaction of (14.6AGeV/c)Si + Au are compared with a simple relativistic hadronic cascade simulation. The theoretical results seem to prefer the statement of strong but incomplete nuclear stopping at AGS energy.

By using the feature that KNbO₃ :Fe bas fast response time, we demonstrate a KNbO₃ :Fe optical frequency discriminator (KOFD) which is based on the method of the-delayed laser-induced double)le gratings. This KOFD can be used to measure the frequency difference between two laser fields.

We present measurements of two-photon absorption (TPA) coefficient of C₆₀ thin film at 633nm. Large values of β~5 cm/W were determined. Nearly-resonant TPA transition around 3.76 eV absorption region was discussed.

By using a pulsed dye Laser of nanosecond level as a pomp source, we have investigated stimulated Raman scattering and stimulated four-photon mixing in Er³⁺ doped silica fibers. The experimental results show that all lines, including the pump radiation line, are obviously broadened and the anti-Stokes lines of stimulated four-photon mixing arc greatly enhanced, and that the enhancement effect is independent of the wavelength.

The small scale density fluctuations in the interior of HT-6M Ohmic plasma have been studied by CO₂ laser collective scattering system in deuterium discharges covering a range of n_eq_a (chord-average density times safety factor at the limiter) and energy confinement time. The relative density fluctuations level in the interior is inversely proportional to the toroidal magnetic field and average density, and the energy confinement time T_E decreases with the fluctuation level increasing in the region where T_E linearly increases with n_eq_a and satisfies the Goldston scaling Jaw. It is suggested that the microturbulence in the interior zone is responsible for anomalous transport in tokamaks.

Neutron diffraction and inelastic scattering were carried out on YBa_2-xSr_x Cu₃O_7-y(x=0.5, 1.0, 1.25). It was confirmed that the substitution of Sr for Ba in YBa₂Cu₃O_7-y increases the oxygen vacancies in the Cu O chain. Moreover, the substitution strengthens the coupling between the Ba O plane the Cu O chain, and reduces the crystal stability. These are possible causes of T_c depression for Sr substituted YBa₂Cu₃O_7-y.

The spiral and ordinary dislocations both running nearly perpendicular to the (001) growth surface of thallium acid phthalate, were revealed and identified by x-ray topography. They play an unexpectedly important role on that face by providing the self-perpetuating step sources so as to accelerate its growth rate or even to change its crystal morphology.

The behaviors of piezoresistivity in a new series of composite materials composed of TiC particles in polyvinyl chloride (PVC) insulating polymer are investigated. Experimental results show a Pronounced change in resistivity with pressure, making the composite materials attractive candidates for pressure or stress sensors with sensitivities much higher than the conventional semiconductive silicon materials. Piczoresistive effect of TiC-PVC composite is related to the difference in the elastic properties of the TiC particles and PVC polymer, and to the large changes in resistivity with concentration close to 25 vol%TiC in composite.

Magnetic hysteresis loops arid magnetization relaxation of a zone-melted YBa₂Cu₃0_6+x sample were measured by superconducting quantum interference device (SQUID) at temperature from 4.5 to 70 K. The logarithmic behavior of magnetic decay at 4.5 K arid the gradual deviation as the temperature is increased demonstrated important role of nonlinear current density dependence of effective flux pinning potential U( J) in high temperature superconductors.

The exact solutions via Bethe ansatz to the One-D spin fluctuation model for J ＞0 and J ＜0 are presented . The bound states are discussed based on the Bethe ansatz equations. It is shown that the antiferromagnetic spin fluctuation leads to bound states like Cooper pairs and ferromagnetic spin fluctuation to no bound state. Also we point out that our model is much similar to the δ–potential Fermi gas model.

Superconducting compound (Sr_0.86Nd_0.14) CuO₂ with the infinite layer structure was synthesized under high pressure. This tetragonal structure a x a transforms into a superstructure 2√2a x 2√2a when the sample was in situ heated in transmission electron microscope to about 600K. An anormalous resistance change of the sample during heating in vacuum to 400°C confirmed the phase transformation. After the superlattice formation, the sample lost its superconductivity and became semiconducting.

A Robertson- Walker geometry with nonminimal coupled scalar field has been quantized by the canonical formulation for constrained Hamiltonian systems. The exact solutions have been found for corresponding Wheeler-DeWitt equation. These solutions satisfy the needs of Hawking's boundary condition for the wormhole wave function. Thus they can provide a quantum-mechanical description of wormholes in a theory with a nonminimal coupled scalar field. The characteristic scale of the ground state of the wormhole is of the order of Planck length.

The second quantization is introduced to the approach proving Hawking radiation, suggested by Damour and Ruffini. A wave packet around an event horizon can be expanded by two alternative complete sets respectively. Making use of the Bogolubov transformation between the two sets of modes, Hawking effect can be shown.