Papers by Author: Ming Li Li

Abstract: The template method combined with sol-dipping deposition or sol-electrophoresis was used to prepare titania (TiO₂) nanowires with shape of rod or string of beads. When irradiated under ultraviolet (UV) light for 1 hour, the degradation rate of methyl orange (MO) using nanowire arrays reached 98.5% which was 1.84 times as much as that of the thin film on glass plate, and when irradiated under visible light for 6 hours, the degradation rate reached 96.7% which was 4.17 times as much as that of the thin film.

Abstract: The template method combined with sol-dipping deposition or sol-electrophoresis was used to prepare titania (TiO₂) nanowires with shape of rod or string of beads. The SEM was used to characterize the surface and cross section of the TiO₂ nanowire arrays. With parallel orientation, the nanowires were uniformly distributed.

Abstract: A new preparation method was developed to produce Si₃N₄-SiO₂-Si₂N₂O composites for broad band radome applications. The three-dimensional cross-linked polyphenylsiloxane (PPS) was used as an organic precursor. The composites obtained through react bonding between Si and the precursor powders in the stream of N₂ were examined. The conversion of the PPS polymer to the ceramic was examined by TG analysis and conventional X-ray diffraction (XRD) techniques. It was found that the ceramics contained a primary Si₂N₂O phase, some β-Si₃N₄ phase and a minor α-SiO₂ phase. Despite low density (1.7-2.0g•cm^-3), the flexural strengths of the composites reaches 195Mpa at room temperature. The ceramic has excellent dielectric properties with dielectric constants as low as 3.2-5.5.