Power scaling of printed-circuit-board preionized TEA CO2 laser up to 3.6 kW

A high average power, high-repetition-rate TEA CO₂ laser employing printed-circuit-board preionizer is described. The power scaling of this preionization configuration has been demonstrated. The average output power reaches 3.6 kW at pulse repetition rate of 180 pps. Furthermore, the scaling-up ability of the rotating spark gap as high-voltage switch for high-average-power gas laser has been validated.     

The primary investigation of optical-limiting effects of optical active phthalocyanine derivative TMBO-SiPc

The optical-limiting property of an optically active phthalocyanine derivative with different configuration in chloroform solution was measured at 532 nm with 10 ns pulses. The excited state absorption cross-section σ_ex of the derivative was determined with the Z-scan technique. The results showed that the phthalocyanine derivative possesses larger σ_ex than the ground state absorption cross-section σ₀, indicating that it is a material for reverse saturable absorption. And it is specially noticed that the change in the optically active configuration affects its optical-limiting property significantly.     

CO_2 Reforming of CH_4 over Ni/CeO_2-ZrO_2-Al_2O_3 Prepared by Hydrothermal Synthesis Method

The Ni/CeO2-ZrO2-Al2O3 catalyst with different Al2O3 and NiO contents were prepared by hydrothermal synthesis method. The catalytic performance for CO2 reforming of CH4 reaction, the interaction among components and the relation between Ni content and catalyst surface basicity were investigated. Results show that the interaction between NiO and Al2O3 is stronger than that between NiO and CeO2-ZrO2.The addition of Al2O3 can prevent the formation of large metallic Ni ensembles, increase the dispersion of Ni, and improve catalytic activity, but excess Al2O3 causes the catalyst to deactivate easily. The interaction between NiO and CeO2 results in more facile reduction of surface CeO2. The existence of a small amount of metallic Ni can increase the number of basic sites. As metallic Ni may preferentially reside on the strong basic sites, increasing Ni content can weaken the catalyst basicity.     

Apparatus for High-Resolution Solid Hydrogen Matrix Isolation Spectroscopy and Its Application

Apparatus integrating a Fourier transform-infrared (FT-IR) spectrometer and a mid-infrared difference frequency generation (DFG) laser spectrometer was built for the study of the matrix isolation spectrum in solid molecular hydrogen. A 3-cm-long molecular hydrogen crystal was grown in a liquid-helium Dewar, and its infrared absorption spectrum in the 1-5 μm region was recorded to test the system. The W₀(0) (ν=0←0, J=6←0) line around 2410 cm⁻¹ of solid hydrogen was investigated with the DFG laser spectroscopy. High-resolution matrix isolation spectrum of CO² co-deposited with hydrogen on a BaF₂ cold plate at liquid-helium temperature was studied.     

KxCoO2·yH2O(x《0.2,y≤0.8)的晶体结构、输运及磁学性质

利用熔融KOH和Co3O4在较低温度(480℃)下反应制备出K0.36CoO2,然后用高锰酸钾溶液和饱和的过硫酸钾溶液进行氧化处理.氧化的同时伴随有水分子嵌入.K0.36CoO2用高锰酸钾和过硫酸钾溶液处理后分别得到K0.12CoO2·0.8H2O和K0.16CO2·0.6H2O.这两种化合物都属于六角晶系,表现出金属行为,脱水后主相变为正交结构并且呈现出半导体特性.K0.16CoO2·0.6H2O在56K附近可能存在自旋玻璃转变行为或其他涨落.随着钾含量的减少和水含量的增多,样品的自旋玻璃行为受到抑制或发生磁性相分离.样品K0.12CoO2·0.8H2O在零场冷却和有场冷却曲线上的分叉现象基本上消失.还讨论了产生KxCoO2与NaxCoO2体系结构和物性差别的原因.     

Enhancement of Overall Photovoltaic Efficiency by Changing the Position of the Attaching Group -RSO3- on the Hemicyanine Dye Molecules

A new photoresponsive D-π-A dye, mPS, has been designed and synthesized.Compared to the parent dye PS, IPCE values in the region from 400 nm to 560 nm was greatly improved upon changing the attaching group from the p- position to the o- position of the π-conjugation bridge. A solar cell based on mPS generated a remarkably high overall yield η of 5.4% under irradiation of 80.0 mW cm^-2 white light from a Xe lamp, Compared with PS, the overall yield η increased by 64%.     

线性代数网上学习系统的开发与研究

本文简要介绍线性代数学习网站的系统研究与开发设计．涉及到网络数据库、ASP、界面设计等多种技术.该线性代数网上学习系统为老师和学生提供了交流平台，其界面美观、操作简便．具有良好的应用前景.     

HL－1装置辅助加热等对能量约束的影响

在ＨＬ－１托卡马克上进行了辅助加热、加料、电流驱动的物理实验研究。在改善等离子体约束方面，某些实验取得了较好的结果。在适当的稳定放电条件下，低杂波电流驱动和弹丸注入辅助加料，均能使等离子体能量约束得到一定程度的改善，与相同密度条件下的欧姆加热放电相比，能量约束时间提高了约３０％。在电子回旋共振加热等离子体实验中，等离子体总能量明显增加，但与相同密度条件下的欧姆加热放电相比，能量约束时间减少了约２０％。     

Studies on the chemical constituents of the South China Sea sponge Phacellia fusca

Three pyrrololactam alkaloids have been isolated from the marine sponge Phacellia fusca Schmidt collected from the South China Sea, and their structures were determined as 1–3 , on the grounds of spectral data. This is the first report of these compounds from this sponge. The structure of 1 was confirmed by X-ray analysis.