Depending on what kind of chemistry you go in to, you might accidentally memorize parts of the table, which is fine, but what you really want to know how to do is know how to use the periodic table.

取决于你今后从事哪个方向的化学研究，你可能会不经意地记住周期表的某一部分，这就够了，但是要注意,你真正需要知道的是如何使用元素周期表。

麻省理工公开课 - 化学原理课程节选

And what we've been talking about with all of these properties are, of course, how can we figure out what that is for a certain atom by looking at the periodic table, so we want to think about the periodic trend for atomic radius.

对于我们讲过的这些性质，我们所讨论的一直都是,当然是，我们如何能够判断某一个原子的这些性质,通过观察周期表，因此我们需要思考一下原子半径的周期性规律。

麻省理工公开课 - 化学原理课程节选

We need to add something else in order to explain what is going on in the Periodic Table.

我们需要引其他一些东西进来才能解释清楚,元素周期表中发生的这种现象。

麻省理工公开课 - 固态化学导论课程节选

So this line or these lines of code up here are arguably constant time steps to say if N is less than 2 in return, that it will always take maybe one step, maybe two steps, some number of fixed CPU cycles.

如果N小于2并返回,那么这些行所对应的代码,通常只需要执行一步，或者两步，具体数字与CPU周期有关。

哈佛公开课 - 计算机科学课程节选

So, then all we need to do to determine which elements that corresponds to is take a look at our periodic table.

因此，我们需要做的只剩下,在元素周期表中寻找,对应的元素有哪些。

麻省理工公开课 - 化学原理课程节选

You will be asked to write down the periodic table.

你需要默写周期表。

麻省理工公开课 - 固态化学导论课程节选

So this is not even thinking about the other electron shielding, just if we think of the fact, all we need to think about is that the effect of going to a further away n n as we go down the table.

到现在我们甚至还没有考虑,其它电子的屏蔽效果，即使我们要考虑这个因素，我们需要考虑也就是,沿着周期表的某一列往下走，距离会逐渐变远,将起最重要的作用，actually，dominates,这一结果所产生的影响。

麻省理工公开课 - 化学原理课程节选

The period, that's right. So, it's going to take one period to move that long. And another way 1 we can say period is just 1 over nu or 1 over the frequency So, now we know both the distance traveled and the time the elapsed.

还是？周期，对的,它需要一个周期的时间,另一种说法是周期是,除以nu，也就是1除以频率,现在我们同时知道了。

麻省理工公开课 - 化学原理课程节选