Abstract : the influence of electron screening on electroncaptu re for the most abundant nuclei in massive stars at the presupernova stage is discussed by using the shell model . it is shown that the total rate of chance of el ectronfraction should be multiplied by a factor of about 0 . 8 0 . 9 with the elec tron screeningtaken into account 文摘:利用核的壳层模型,讨论了电荷屏蔽对超新星的前身星阶段一些较丰的核在一些重要的温度-密度点的电子俘获率的影响,结果表明由于电荷屏蔽的作用其电子丰度变化率须乘以一个0 . 8 0 . 9的因子