等电荷态离子与He原子碰撞中的转移电离过程研究

采用位置灵敏探测和飞行时间技术测量了等电荷态离子C^q 、N^q 、O^q 、Ne^q (q=4，5，6，7)与He原子碰撞中，转移电离截面与单电子俘获截面的比值Ro研究了相同q入射的情况下，R与入射离子核电荷数Z的依赖关系。在统计蒸发模型的基础上对实验结果进行了解释。     

氟化类金刚石薄膜的拉曼和红外光谱结构研究

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Deposition of Diamond-Like carbon Films by High-Intensity Pulsed Ion Beam Ablation at Various Substrate Temperatures

Diamond-like carbon (DLC) films have been deposited on to Si substrates at substrate temperatures from 255℃ to 400O℃ by a high-intensity pulsed-ion-beam (HIPIB) ablation deposition technique. The formation of DLC is confirmed by Raman spectroscopy. According to an x-ray photoelectron spectroscopy analysis, the concentration of sp^3 carbon in the films is about 40% when the substrate temperature is below 300℃ C. With increasing substratetemperature from 25℃ to 400℃, the concentration of sp^3 carbon decreases from 43% to 8%. In other words,sp3 carbon is graphitized into sp^2 carbon when the substrate temperature is above 300℃. The results of xray diffraction and atomic force microscopy show that, with increasing the substrate temperature, the surface roughness and the friction coefficient increase, and the microhardness and the residual stress of the films decrease.     

Stone代数的Cayley表示定理

首先通过集代数得到了Stone代数的表示定理,然后证明了每一个Stone代数均嵌入到某个集合X上的一个Stone映射类S中.     

四维Minkowski空间中类时超曲面的de Sitter Gauss映射的奇点分类

本文通过类时超曲面与超平面的切触关系, 对类时超曲面的de Sitter Gauss映射的奇点进行了分类.