One is there's no lag period, notice that antibody levels start rising right away after the second exposure.

第一是没有迟滞期,请注意,抗体浓度迅速上升,在第二次接触抗原时

耶鲁公开课 - 生物医学工程探索课程节选

s1 So for the fourth period, now we're into the 4 s 1 3d for potassium here. And what we notice when we get to the third element in 4s2 and the fourth period is 3d that we go 4 s 2 and then we're back to the 3 d's.

对于第四周期到现在我们来到钾的1,然后我们返回到,我们注意到当我们看到第三个元素,第四周期我们来到,然后我们返回到。

麻省理工公开课 - 化学原理课程节选

It is also interesting to notice who does not colonize at this early period and the answer is all the most famous cities of Greece in the Classical Period.

另一个有意思的问题是,谁在早期并不殖民,答案是,古希腊时期的所有名城

耶鲁公开课 - 古希腊历史简介课程节选