激光干涉法诊断空气开关等离子体的技术研究

介绍了激光干涉技术用于诊断等离子体的基本原理、实验装置及图像处理方法等,通过Mach-Zehnder激光干涉仪诊断了空气开关等离子体。结果表明,该实验装置能够获得高质量的干涉图。通过对干涉图的数值处理,重建了等离子体电子密度的三维分布。空气开关放电后75ns时刻,等离子体的平均电子密度为2×10~(18) cm~(-3),电子温度为0.11eV,等离子体半径为1.1mm,扩散速度为1.4×10~4 m/s。     

Preparation and Photocurrent Performance of Highly Ordered Titania Nanotube Implanted with Ag/Cu Metal Ions

Ag/Cu-doped titania nanotubes （Ag/TiNT, Cu/TiNT） are prepared by a metal vapor vacuum arc implanter. A scanning electronic microscope is employed for microstruetural characterization. The photo-current performance of doped titania nanotubes under UV and visible light is tested by an electrochemical workstation CS300UA, the results show that the absorption edge of both Ag/TiNT and Cu/TiNT samples shifts to the visible light region and the band gap becomes narrower. Ag/TiNT possesses better photo-current ability than Cu/TiNT under UV and visible light. Titania doped with Ag and Cu metal ions is also studied based on the linearized augmented planewave method implemented by WIEN2k package, the result becomes better with the experimental performance.     

Calculation of Electronic Structure of Anatase TiO2 Doped with Transition Metal V,Cr,Fe and Cu Atoms by the Linearized Augmented Plane Wave Method

The electronic density of states and band structures of doped and un-doped anatase TiO2 were studied by the Linearized Augmented Plane Wave method based on the density functional theory. The calculation shows that the band structures of TiO2 crystals doped with transition metal atoms become narrower. Interesting, an excursion towards high energy level with increasing atomic number in the same element period could be observed after doping with transition metal atoms.