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So, what we've got here is a source of alpha particles.
我们已经有了一个阿尔法粒子源。
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And there he was able to identify the alpha particle as the helium nucleus.
他证实了,阿尔法粒子就是氦核。
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But it's really interesting the studies that he did do with radium bromide, and he was studying the alpha particles.
但他用溴化镭,做的研究十分有意思，他研究的是alpha粒子。
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This is the analogy to the alpha particle.
这和阿尔法粒子类似。
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He shot alpha particles which have a charge of plus two.
他入射的阿尔法粒子带有两个正电荷。
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Rutherford used alpha particles.
卢瑟福用的是阿尔法粒子。
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And no, it wasn't. When he took away the gold foil the count rate went down to zero.
看看是不是从,其他地方打进来的alpha粒子,但不是，当他拿走。
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And what was known about alpha particles at the time is that they were these charged particles and that they were very heavy.
当时对alpha粒子的理解,是它们是带电的而且非常重，有谁知道的,比Rutherford时代的多吗。
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So, this is an absolutely outstanding discovery, even though, if we think about it, what is the probability that this happened, how often did this happen?
0个alpha粒子，这绝对是一个，很了不起的发现，虽然我们仔细想想？
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And what he would expect is if this Plum Pudding model is true, nothing's really going to happen to the particles, right, they should go straight through, because if they hit an electron, those are so small.
他所预期的是,如果李子布丁模型，是正确的，alpha粒子,不会发生什么事情,对吧，它们会直接穿过去,因为如果它们撞到电子。
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Does anyone know more than what Rutherford knew at the time, what alpha particles actually are?
知道alpha粒子是什么吗？,是的，很好，它们实际上是氦原子？
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We have to build this whole new detector, is this really the best use of my time?
最后测到了132000个alpha粒子，我们还要找什么？
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So basically he's trying to put some atoms in the way of the alpha particle.
把一些原子,放在alpha粒子的路径上。
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So, what he could conclude thus far was that this was really consistent with the Plum Pudding model. All of his heavily-charged alpha particles were going right through this thin layer of gold atoms.
和布丁模型是吻合的,所有的重alpha粒子,都穿过金原子,你们也许会觉得,他可以就此。
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And this is exactly what happened with Marsden who discovered that when he shot the alpha particles at the gold foil he detected something on his detector that click, click, click went a little bit faster.
而对于Marsden来说,就是这样，他发现当他用alpha粒子,轰击金箔的时候，探测器哒哒哒得更快了,他发现一分钟。
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So, what he detected was that there were 20 alpha particles per minute.
可以探测到20个alpha粒子,这个听上去很重要吗？
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We know we started with a 132 000 alpha particles.
看看能不能看到alpha粒子有些人就会问：
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What are we even looking for?
开始有132000个alpha粒子？
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About 10 to 15 years later, another physicist, Ernest Rutherford, actually put this plum pudding model to test, Ernest Rutherford and he did it through studies that he'd been doing on radiation that was emitting something called alpha particles.
因此我们要，在上面再做改进,大概过了10到15年，另外一个物理学家,用实验来检测这个李子布丁模型,他一直从事alpha粒子辐射研究。
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