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You just need to remember what's happening to z effective, which really tells us what's happening with all the trends, and once you know z effective, you can figure out, for example, what direction the atomic radius should be going into.
你只需要记住有效核电量的规律，实际上它会告诉我们所有的规律，只要你知道了有效核电量的规律，你就可以判断，比如，原子半径会向着哪个方向发展。
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I put the new trends that are out. So you know,
我会把最新款的放在外面的位置。所以，
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just empirically speaking about the Harvard students, looking the trends and statistics-- empirically speaking, Americans are the most generous people in the world.
或只是说哈佛学生，根据发展趋势和统计，美国人是世界上最慷慨的人。
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We'll then take a turn to talking about the periodic table, we'll look at a bunch of periodic trends, including ionization energy, electron affinity, electronegativity and atomic radius.
然后我们再开始讲元素周期表，我们会看到很多周期性规律，比如电离能，电子亲和能，电负性以及原子半径。
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As I told you, on the first day, I do look at trends.
我告诉你，第一天开始我看重的是趋势。
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So this is, in effect, the backdrop in which in the American academy--influenced, - as we'll now see, by certain trends in the British academy-- arose in the thirties and in the forties.
所以实际上,这就是当时美国学术界，受英国学术界影响-,在三四十年代崛起的背景。
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And there's a lot we can explain by talking about what we see in the periodic table in terms of what different trends are in grouping different elements in different spots within the periodic table.
我们可以解释很多,通过讨论元素,周期表中的内容,按照各种不同的规律,将周期表中不同位置的元素分组归类。
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So, this means we have the general trends down, so we should be able to look at actual atoms in our periodic table and graph them and see that they match up with our trends.
那么，这表示我们已经知道了大体的规律，现在我们可以来看看周期表中的,原子的实际情况，并把它们画出来,看看是否与我们的规律相符。
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But you actually need to keep a few caveats in mind as you do this, which is the fact that trends predict a lot of chemical properties, but they can't predict everything in terms of biological properties.
不过在你使用的过程中,需要牢记一些注意事项,那就是元素周期律可以预言很多化学性质，但是不能预言一切性质,比如生物学性质。
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And the glitch that doesn't make sense just through periodic trends, is that it turns out that the ionization energy of boron is actually less than the ionization energy up beryllium.
仅仅考虑周期性规律,是无法理解这个问题的，这里显示硼的电离能,实际上比铍的要小。
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This is about the periodic trends that we discussed on Wednesday.
这是关于我们在周三讲过的,周期性规律的。
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So, again, this is one of the more straightforward trends.
再说一遍，这是一个更简单直接的规律。
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It decreases. If you're still not completely up on the periodic trends, that is stuff that's going to be on the first exam, so make sure that you're able to do this without taking too much time to think about it.
它会降低，如果你还没有完全掌握周期性规律，而这是第一次考试要求的内容，因此请务必做到不用,想太久就能做到这点。
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And I also wanted you to identify why, it's also important to understand why we have these trends, not just to memorize the trend itself.
而且我还需要大家判断原因是什么，这很重要，对于我们理解,为什么有这些规律，仅仅记住这些规律是不够的。
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So let's turn our attention to a new topic, which is thinking a little bit about the periodic table, and also talking about periodic trends.
我们的新主题上，我们将会讨论一点关于元素周期表的知识，同时也会讲一讲周期性规律。
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