详细信息
Li_2O-Na_2O-Al_2O_3-SiO_2系玻璃中的Na^+自扩散
Na^+ Self Diffusion in Li_2 O-Na_2 O-Al_2O_3-SiO_2 System Glasses
文献类型:期刊文献
中文题名:Li_2O-Na_2O-Al_2O_3-SiO_2系玻璃中的Na^+自扩散
英文题名:Na^+ Self Diffusion in Li_2 O-Na_2 O-Al_2O_3-SiO_2 System Glasses
作者:杜永娟[1];周永祥[2]
机构:[1]华东化工学院无机材料系;[2]华东化工学院物理系
年份:1989
卷号:15
期号:6
起止页码:750
中文期刊名:华东化工学院学报
收录:Scopus;CSCD:【CSCD2011_2012】;
语种:中文
中文关键词:玻璃;钠离子;自扩散;Li2O;Na2O
外文关键词:sodium ion; self diffusion; activation energy; glass; concentration dependence; mixed alkali effect: radioactive isotope method
摘要:应用放射性同位素法,研究了xLi_2O·(31.8-x)Na_2O·5.8Al_2O_3·62.4SiO_2(mol%)系玻璃中的Na^+自扩散温度范围为250~450℃。从实测数据,用数值法与图解法求得Na^+的自扩散系数D_(Na)~*。根据玻璃的组成和扩散温度,D_(Na)~*值变化于8.8×10^(-8)~1.1×10^(-11)cm^2s^(-1)。随着玻璃中Na_2O含量的减少,D_(Na)~*逐渐降低,显示明显的双碱效应。由不同碱离子的Dietzel场强之差,讨论了这种双碱效应。D_(Na)~*随温度指数上升,符合Arrhenius方程。据此方程,应用最小二乘法,获得扩散活化能E和指数前项D_o,E值约为79~91kJ/mol。
The Na^+ self diffusion in x Li_2O·(31.8-x) Na_2O·5.8 Al_2O_3· SiO_2 glasses (mol%) was studied at 250~450℃ by the radioactive isotope method. The Na^+ self diffusion coefficient D_(Na)~*, was numerically and graphically evaluated from the measured diffusion profile. D_(Na)~* varies between 8.8×10^(-8)~1.1×10^(-11)cm^2s^(-1), depending on the glass composition and the diffusion temperature. With increasing Na_2O-content in the glass, D_(Na)~* increases gradually, showing a pronouced mixed alkali effect, which was discussed on the basis of the difference between Dietzel's field strengths of the different alkali ions. D_(Na)~*, increases exponentially with the temperature and obeys Arrhenius equation. According to this equation the activation energy E and the preexponential term D_0 were evaluated by using the least square method. The value of E is about 79~91 kJ/mol.
参考文献:
正在载入数据...
