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ÇóÖú¸÷λÄÜÈË¡£ СµÜ×î½ü¿´µ½Ò»ÆªÎÄÏ×ÊǹØÓÚCeO2ÔÚ²£Á§ÌåÖеļì²â¡£ ÀïÃæ¸øÁËÕâôһ¸öͼ XRD patterns gave direct evidence of CeO2 nanocrystals in RTT glasses, whereas no diffraction peaks could be detected in non-RTT samples with less than 5 mol% Ce (cf. the 1% case in Figure 4£¨¾ÍÊÇÎÒÉÏ´«µÄÕâÕÅͼ£©). Raman spectra cannot give directly the value of the CeO2 cluster dimensions, but need calibration through XRD or TEM analysis. By use of the full widths at half-height of the CeO2 X-ray diffraction peaks, analyzed through the Scherrer equation, the mean crystalline size was determined in the glasses containing 1, 2, 3, and 5 mol % Ce after RTT, obtaining values in the 15-20 nm range (Figure 5£¨ÉÏ´«µÄµÚ¶þÕÅͼ£©).A calibration on well-crystallized CeO2 was taken into account. The error bars in Figure 5 correspond to deviations between results from different Bragg peaks in the CeO2 XRD pattern. In the case of the 5% sample before RTT, very broad peaks appeared corresponding to a crystal size of about 5 nm. ÕâÀïÃæ˵¸ù¾ÝÔÚCeO2µÄXRDÖв»Í¬²¼À­¸ñ·åÀ´È·¶¨µÄÎó²î¡£Ê×ÏȶÔÓÚ²¼À­¸ñ·åСµÜ¾Í²»ÊǺÜÃ÷°×ÊÇʲô¶«Î÷¡£ÔÚÍøÉϲéÁËÒ»ÏÂҲ˵µÃ²»Çå²»³þµÄ¡£µÚ¶þ£¬Èç¹ûÎÒҪŪÇå³þÕâ¸öÎó²îµ½µ×ÊÇÔõô¼ÆËãµÄÊDz»ÊÇ»¹ÒªÈ¥ÕÒCeO2ÔÚXRDÀïÃæµÄ²»Í¬µÄ²¼À­¸ñ·å£¬Õâ¸öÒªÔõôÕÒ£¿Çó½Ì´óʦ¡£ (Fig. 4) Fig. 5

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