| The thesis emphasizes on the irradiation resistance of lead-free glasses and luminescence properties of Pr3+ doped glasses. The main research results are shown as follows.The y-ray irradiation effects on Bi2O3 based borosilicate glasses doped with CeO2 and/or TiO2 are investigated. TiO2 has played a positive role in increasing the irradiation resistance properties of Bi2O3 based glasses, while CeO2 hasn't exhibited the expected effect due to the impact of the high oxidation-reduction potential of Ce4+/Ce3+ pairs, which most likely take part in the reaction process as oxidant in the course of of glass formation. Damage recovery ability of the glasses is pretty low, which depends less upon the compositions of matrix glasses than the kinds of doped stabilizing agents.Intra- and inter-configurational luminescence properties of Pr3+ doped strontium phosphate glasses are studied under excitation wavelength of 290 nm and 447 nm, respectively. Under the excitation at 447 nm, the ratios of intensities of blue, green and red light to that of yellow light can be controlled by adjusting the concentration of Pr3+ ion. And under the excitation at 290 nm, an intensive broad UV emission due to 4f15d1â†'4f2 is observed.The effects of co-dopants, that is, Pr3+-Dy3+ and Pr3+-SnO2, upon the luminescence properties of Pr3+ ion are investigated. Experimental results show that the intensity of Pr3+ ion is enhanced by efficient energy transfer process from Dy3+ ions. Theoretical analysis reveals that the dominant mechanism of energy transfer from Dy3+ ion to Pr3+ ion is quadrupole-quadrupole interactions with the estimated transfer efficiency up to 52.9%. The energy transfer from SnO2 to Pr3+ ion can also be observed in the Pr3+-SnO2 co-doped glasses. Under the excitation at 267 nm, a broad emission with a width at half-maximum about 230 nm is observed, which is bridged by the UV emission of Pr3+ and blue emission of SnO2. Besides, a new red emission at 610 nm appears. |
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