中文摘要：

采用最大拉力圆环法精确系统地测量了锗酸铋熔体体系xBiν20ν3．（1-x）Ge0ν2在0．15〈x≤0．86范围内的表面张力．结果表明：当X≤0．40时，熔体的表面张力随温度的升高而增加；当X≥0．40时，熔体的表面张力随着温度的升高而减小．通过对实验数据的拟合，讨论了表面张力的温度系数dy／dt和体积膨胀系数β等热力学性质．着重讨论了锗酸铋熔体出现的正表面张力系数，并指出单靠Gibbs吸附原理来解释表面张力的温度系数的正负问题是不够完善的．

英文摘要：

The surface tensions of xBi203-（1-x）GeO2 melts of different compositions with 0.15〈x≤0.86 have been measured precisely and systematically by using thering method. The results obtained show that from their melting points up to 1 480 K, when x≤0.40 the surface tensions of the melts increase with the increasing temperature, while x i≥0.40 the values of the surface tension decreased with the increasing temperature. In addition, the temperature coefficients of the surface tension （dγ/dT） and the volume expansion coefficient （β） are calculated from the fitting curves of the surface tension and the density, respectively. The positive and negative temperature coefficients of surface tension have been observed in bismuth germanate system. We discuss further the positive temperature coefficients and a conclusion is drawn that the positive temperature coefficients of the surface tension can not been explained well only by the Gibbs adsororption rule.