976 resultados para SIO2


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Silica spheres doped with Eu(TTFA)(3) and/or Sm(TTFA)(3) were synthesized by using the modified Stober method. The transmission electron microscope image reveals that the hybrid spheres have smooth surfaces and an average diameter of about 210 nm. Fluorescence spectrometer was used to analyze the fluorescence properties of hybrid spheres. The results show that multiple energy transfer processes are simultaneously achieved in the same samples co-doped with Eu (TTFA)(3) and Sm(TTFA)(3), namely between the ligand and Eu3+ ion, the ligand and Sm3+ ion, and Sm3+ ion and Eu3+, ion. Energy transfer of Sm3+-> Eu3+, in the hybrid spheres leads to fluorescence enhancement of Eu3+ emission by approximately an order of magnitude. The lifetimes of the hybrid spheres were also measured.

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The interaction of Co with Si and SiO2 during rapid thermal annealing has been investigated. Phase sequence, layer morphology, and reaction kinetics were studied by sheet resistance, x-ray diffraction, Auger electron spectroscopy, x-ray photoelectron spectroscopy, and scanning electron microscopy. With increasing annealing temperature, Co film on Si(100) is transformed sequentially into Co2Si, CoSi, and finally CoSi2 which corresponds to the minimum of sheet resistance. No evidence of silicide formation was observed for Co/SiO2 annealed even at the high temperature of 1050-degrees-C.

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用双源电子束蒸发的方法,在K9玻璃基片上蒸镀Si和SiO2的混合膜.通过改变两种膜料蒸发速率的比例,得到的各个膜层,其折射率大小在两种膜料折射率之间的范围内变化.从实验上得出了混合膜层的折射率随Si和SiO2蒸发速率比变化的规律,并讨论了这种淀积方法的优越性.