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"But our intelligence community failed to connect those dots."
VOA: standard.2010.01.05
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So, one way we could look at it is by looking at this density dot diagram, where the density of the dots correlates to the probability density.
其中一个理解它的方法,就是通过看这个密度点图，这里点的密度,和概率密度想关联的。
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They have polka dots on them.
鞋上有圆点的花纹。
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DOTS,the Stop TB Strategy was launched in 1994.
VOA: standard.2009.12.09
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And I don't have to worry about these relative dimensions because we know from Marsden's calculations that, on the length scale that I have shown here, these would be just tiny little dots.
我们不必考虑,它们的相对大小,因为从马斯登的计算中我们可以得知，就从我现在给你们演示的这种相对距离来说，这些电子将只是一些很微小的斑点。
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Then, the next challenge was to figure out how to keep the dots on the streets because they were going all over the place.
接下来的挑战是,想办法让这些点固定在,街上，因为,它们总是不停地移动。
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So I said that we want to be talking about valence electrons here, so that means if we're talking about, for example, the octet rule for an f f molecule where we have two fluorine atoms, we need to write the valence electrons as dots around them.
我说过我们在这要讨论的是价电子，这就意味着，如果我们要讨论，比如，关于两个氟原子组成的分子的八隅体规则,我们首先需要把价电子画成围绕在它们周围的点。
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This picture on the bottom here is really just a series of colored dots.
最底下的这张图中,只有一系列彩色的点
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And then, I learned how to move the dots around.
接着我学会了怎样移动这些小点。
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They're just random dots moving around this city.
它们只是随机的点，在城市里移动。
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And then, I put some dots on the map.
接着，我在上面画上了很多小点。
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These are all things that the Bawendi group is working on. What they are real experts in is synthesizing many different kinds of these dots, and they have a synthetic scheme that's used by research groups around the world.
这些是Bawendi组正,在做的工作，他们擅长的是,合成各种量子点，他们的,方法已经被世界各地的,实验组采用，他们组还和。
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So, again we can use these probability density plots, which are just a plot of psi squared, where the density of the dots is proportional to the density, the probability density, at that point.
同样的我们可以利用这些概率密度图，这是psi的平方的图，这里面点的密度，正比于概率密度。
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These junctions, these red dots here are actually made up of proteins, some are synthesized by one cell, some are synthesized by each other, and they lock together to form a very tight barrier, to form a tight junction between the two cells.
这些红点表示细胞连接,实际上是由蛋白质构成的,有些是由一个细胞单独生成的,有些是由两个细胞共同生成,使这两个细胞紧锁在一起形成紧密的屏障,并在两细胞间形成紧密连接
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And the idea is that when you do these Lewis dot structures, we're representing electrons with dots, which we'll see in a minute, and each dot is going to represent a valence electron.
而当你遇到这些路易斯点结构时，我们会将电子用点来表示，我们马上就会看到，每个点都代表了一个价电子。
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And then, I had all these dots moving around this beautiful picture of this map, which represented downtown St. Louis and then later represented New York City, which I was amazed by.
接着我让这些点在这张,漂亮的地图上动来动去，让它们展现出圣路易斯市中心的景象,之后表示出了纽约城，这让我很惊奇。
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So, what you see is near the nucleus, the density is the strongest, the dots are closest together.
你看在核子附近，密度非常高，这些点非常密。
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The issue was that none of the dots had any meaning whatsoever.
问题是，这些点,都没有任何意义。
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So, let's go back to the notes, and let's fill these in, seven electrons. Another way you could have known them was to look at Lewis' notes here, where if look at this box carefully you see there are seven dots around the cube, so there are his seven valence electrons.
那么，让我们回到讲义，把它们填进去，七个电子，还有另外一种方法可以知道这些,那就是看看路易斯的讲义这里，大家可以看到这个立方体周围有七个点,因此有七个价电子。
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So really what I want to point out here is as we get more into describing quantum mechanics these quantum dots are one really good example where a lot of the properties of quantum mechanics apply directly. So, if you're interested, I put the Bawendi lab research website onto your notes.
我真正想说的是，随着,我们学习量子力学的深入,这些量子点是很多量子,力学性质得到直接应用的很好例子,如果你们感兴趣的话，我把Bawendi实验室的,网站放到你们的讲义里去。
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