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Physical properties, such as dielectric loss, acoustic velocity and electrical conductivity of glasses containing several glass-forming oxides were measured at temperatures in the range from −200°C to 200°C. The relationships between the structure and properties of the glasses, and the change in coordination number of individual glass-forming cations in alkali-containing glasses were analysed. It is shown that the glasses containing several glass-forming oxides are characterized by an inhomogeneous structure. 相似文献
94.
Transition metal (TM) ions have been used as colouring agents in the glass industry for a long time. Recently, great attention has been paid to the TM ion doped glasses for the development of new lasers or luminescence materials. The absorption spectra of TM ions in different kinds of glasses have been studied extensively, but little work has been done for fluorescence and relaxation spectra. In this paper emphasis is laid on analysing the influence of chemical bond characteristics of the base glass on the spectra and the site structure of transition metal ions in glasses. Recent experimental results about the luminescence characteristics of low valence ions (such as Ti3+, Cr3+, V2+, Mn2+, Cu+, Mo3+) in glasses are also reported. 相似文献
95.
Blue ray optical storage is one of the important trends in the area of information storage, and attracts a number of researchers. Static tester for blue ray optical storage plays an important role in storage media research. We designed and constructed a static tester, in which modularization makes it very convenient to expand function. Employment of modulation/demodulation technique weakens test error so as to increase test precision. Focus move mode and the nano-positioners facilitate the relocation of recording marks. Only one laser with wavelength 406.7 nm is used. In this paper, system design and characteristics are represented in detail, and some experimental results are also given to show that the static tester can perform successfully, acting as research platform for blue ray optical storage. 相似文献
96.
亚酞菁薄膜的光谱和光存储性质研究 总被引:3,自引:0,他引:3
利用真空蒸镀法制备了一种新的三硝基溴硼亚酞菁(BTN-SubPc)薄膜。在室温下测试了该亚酞菁染料在溶液和薄膜态的吸收光谱、薄膜态的反射和透过光谱,发现该薄膜在500nm-650nm波长范围内具有优良的吸收和反射特性。在632.8nm光盘静态测试仪上测试了覆盖有金属反射层的BTN-SubPc薄膜的静态光存储性能,结果表明,用较小功率和较窄脉宽的激光辐照膜片时,可获得大于30%的反射率对比度,显示出该材料用作短波长光存储介质(特别是用于可录型数字多用光盘)的巨大潜力。 相似文献
97.
Da Yue CHEN Fu Xi ZHANG 《数学学报(英文版)》2007,23(11):1949-1954
The authors consider the simple random walk on the infinite cluster of the Bernoulli bond percolation of trees, and investigate the relation between the speed of the simple random walk and the retaining probability p by studying three classes of trees. A sufficient condition is established for Galton-Watson trees. 相似文献
98.
Ti:Al2O3晶体的电子自旋共振谱研究 总被引:2,自引:1,他引:1
Ti:Al2O3晶体中的顺磁中心Ti^3+由于强烈的晶格自旋耦合而使其电子自旋共振吸收只有在液拟温度附近才能看到,本实验在液氮温度附近记录到由许多强的的吸收峰迭加于Ti^3+宽吸收线所组成的电子自旋共振谱,这些吸吸收峰被认为是Al2O3基质中的Fe^3+,Mn^2+,Cr^3+,Mo^3+,Fe^2+,Co^2+等杂质的共振吸收及Ti^2+3A2g基态的双量子跃迁造成的。 相似文献
99.
用单块电子俘获器件,以一种新方法一时域编码方法,实现了所有16种布尔逻辑运算.根据电子俘获材料的存贮和可擦除特性,按特定顺序进行一系列单元操作,可测到每种布尔逻辑函数,同一般光学逻辑处理器相比,这种处理器具有新的自由度一时域自由度,文末给出了实验结果. 相似文献
100.
报道了在C60与NH2(CH2)3Si(OC2H5)3中的胺基反应生成C60-NH2(CH2)3Si(OC2H5)3物质后引入r-缩水甘油醚基丙基三甲氧基硅烷「CH2OCHCH2OCH2CH2CH2Si(OCH3)3,3-Glycidoxypropltrimethoxysilane,简称KH560」与二甲基二乙氧基硅烷「(CH3)2Si(OC2H5)2,Diethoxydimethylsilane 相似文献