We studied the local structure and properties of six-fold coordinated silicon(Si[6]) in BaOSiO2-P2O5 glasses. Nuclear magnetic resonance(NMR) and Raman spectroscopy revealed the existence of sixfold coordinated silico...We studied the local structure and properties of six-fold coordinated silicon(Si[6]) in BaOSiO2-P2O5 glasses. Nuclear magnetic resonance(NMR) and Raman spectroscopy revealed the existence of sixfold coordinated silicon species and network former units(NFUs) in the BaO-SiO2-P2O5 glasses. The glass transition temperature(Tg), which was measured by differential scanning calorimetry, increased rapidly along with the increase of SiO2 from 0 to 10 mol%, then declined and finally increased again, which showed a "Z" trend along with the increase of SiO2 while the density of the glasses showed the opposite trend. When the addition of SiO2 is 16 mol%, Tg decreased to an extremely low value(807.9 K). Besides, the Vickers indentation hardness(Hv) had been significantly enhanced from 4.66 to 6.63 GPa by adding 16 mol% SiO2. Furthermore, the liquid fragility index(m) of the glasses declined slowly firstly and then increased rapidly when the amount of SiO2 is greater than 13 mol%.展开更多
提出了一种新的可用于RoF(Radio over Fiber)系统的六倍频毫米波信号的产生方法,通过设置两级联MZM调制器各自的偏置状态,并联合控制它们之间的光载波时延以及驱动信号间的相位差,来产生六倍频毫米波信号。在毫米波信号模块产生的基础上...提出了一种新的可用于RoF(Radio over Fiber)系统的六倍频毫米波信号的产生方法,通过设置两级联MZM调制器各自的偏置状态,并联合控制它们之间的光载波时延以及驱动信号间的相位差,来产生六倍频毫米波信号。在毫米波信号模块产生的基础上,针对两种不同的数据加载方式,构建相应的下行传输链路,对光毫米波传输特性进行了理论分析和仿真验证。展开更多
基金Funded by National Natural Science Foundation of China(Nos.51772223,51372180)
文摘We studied the local structure and properties of six-fold coordinated silicon(Si[6]) in BaOSiO2-P2O5 glasses. Nuclear magnetic resonance(NMR) and Raman spectroscopy revealed the existence of sixfold coordinated silicon species and network former units(NFUs) in the BaO-SiO2-P2O5 glasses. The glass transition temperature(Tg), which was measured by differential scanning calorimetry, increased rapidly along with the increase of SiO2 from 0 to 10 mol%, then declined and finally increased again, which showed a "Z" trend along with the increase of SiO2 while the density of the glasses showed the opposite trend. When the addition of SiO2 is 16 mol%, Tg decreased to an extremely low value(807.9 K). Besides, the Vickers indentation hardness(Hv) had been significantly enhanced from 4.66 to 6.63 GPa by adding 16 mol% SiO2. Furthermore, the liquid fragility index(m) of the glasses declined slowly firstly and then increased rapidly when the amount of SiO2 is greater than 13 mol%.
文摘提出了一种新的可用于RoF(Radio over Fiber)系统的六倍频毫米波信号的产生方法,通过设置两级联MZM调制器各自的偏置状态,并联合控制它们之间的光载波时延以及驱动信号间的相位差,来产生六倍频毫米波信号。在毫米波信号模块产生的基础上,针对两种不同的数据加载方式,构建相应的下行传输链路,对光毫米波传输特性进行了理论分析和仿真验证。