标题： 利用调幅压力和非经典成核理论估算岩浆中气泡核的表面张力 显示英文标题

标题： Surface tension estimation of bubble nuclei in magma using spinodal pressure and nonclassical nucleation theory

摘要： 努力通过理论模型和实验室实验来估算火山产物的气孔结构中的熔岩减压速率已经取得进展。理论模型基于成核理论，其中熔体与气泡核之间的表面张力是最强影响成核的参数。 由于直接估算表面张力很困难，人们通过反演实验样品的气泡数密度（BND）来计算它，使用经典或非经典成核理论公式。 然而，在考虑表面张力饱和度依赖性的非经典情况下，以前未知自旋odal极限（表面张力变为零的地方）的压力，这需要复杂的数学运算。 在这项研究中，通过对水饱和硅酸盐熔体近似为由硅酸盐和水组成的两组分对称规则溶液，自旋odal压力从吉布斯能曲线确定后被代入非经典公式。 这种方法使得利用过去的减压实验数据更直接地估算表面张力成为可能。 尽管如此，得到的表面张力值比使用经典公式的更分散，表明目前用非经典公式应用于岩浆起泡是不合适的。 解决这个问题可能需要综合理解表面张力对饱和度和气泡半径的依赖性。 这种理解将能够更准确地估算表面张力，并有助于协调理论和实验BND值之间的差异。 显示英文摘要

摘要： Efforts to estimate the magma decompression rate from the vesicular texture of volcanic products have progressed through the development of theoretical models and laboratory experiments. The theoretical model is based on nucleation theory, with the surface tension between the melt and bubble nucleus being the parameter that most strongly governs nucleation. Since direct estimation of surface tension is difficult, it has been calculated by inverting the bubble number density (BND) from experimental samples using classical or nonclassical nucleation theory formulas. However, in the nonclassical case, which accounts for the supersaturation dependence of surface tension, the pressure at the spinodal limit (where surface tension becomes zero) was previously unknown, necessitating complex mathematical operations. In this study, the spinodal pressure determined from the Gibbs energy curve was substituted into the nonclassical formula by approximating the water-saturated silicate melt as a two-component symmetric regular solution composed of silicate and water. This approach allowed for a more straightforward estimation of surface tension using data from past decompression experiments. Nevertheless, the resulting surface tension values were more scattered than those obtained using the classical formula, suggesting that applying the nonclassical formula to magma vesiculation is not valid at present. Resolving this issue will likely require an integrated understanding of the dependence of surface tension on both supersaturation and bubble radius. Such understanding would enable more accurate estimation of surface tension and contribute to reconciling the discrepancy between theoretical and experimental BND values.