2015-05-06 BBC:星光七纪元-31
时间：2019-01-23 作者：英语课 分类：探索与发现2015年
And with his colleagues, he did the calculations to prove it. The key was the conditions created in the final stages about massive stars fighting against its gravity. These stars are so massive and hot that they can go through a whole series of nuclear reactions. The ashes of one set of nuclear reactions becomes the fuel for the next set of nuclear reactions. The most massive stars are able to fuse heavier and heavier elements in the series of layers, creating the energy to resist the relentless 1 inward pull of gravity. There is neon and magnesium 2 and more oxygen, then the silicon 3 and sulphur, and finally, in the middle, a core of Iron. And that’s where the fusion 4 starts. With fusion at an end, there is no more energy to fight back. And gravity wins the battle. The star is doomed 5. When that ball of iron, which is a certain critical mass, about the size of the earth but much, much more massive, the electron pressure is no longer able to support it against the inward force of gravity, so it starts to collapse 6. It collapses 7 to a ball, about the size of a city and then rebounds 8, and that rebounce hits the surrounding layers, launching a supernovae explosion. It’s the speed and violence of the collapse of the star’s iron core that triggers the supernovae.
- The traffic noise is relentless.交通车辆的噪音一刻也不停止。
- Their training has to be relentless.他们的训练必须是无情的。
- Magnesium is the nutrient element in plant growth.镁是植物生长的营养要素。
- The water contains high amounts of magnesium.这水含有大量的镁。
- This company pioneered the use of silicon chip.这家公司开创了使用硅片的方法。
- A chip is a piece of silicon about the size of a postage stamp.芯片就是一枚邮票大小的硅片。
- Brass is formed by the fusion of copper and zinc. 黄铜是通过铜和锌的熔合而成的。
- This alloy is formed by the fusion of two types of metal.这种合金是用两种金属熔合而成的。
- The court doomed the accused to a long term of imprisonment. 法庭判处被告长期监禁。
- A country ruled by an iron hand is doomed to suffer. 被铁腕人物统治的国家定会遭受不幸的。
- The country's economy is on the verge of collapse.国家的经济已到了崩溃的边缘。
- The engineer made a complete diagnosis of the bridge's collapse.工程师对桥的倒塌做了一次彻底的调查分析。
- This bridge table collapses. 这张桥牌桌子能折叠。
- Once Russia collapses, the last chance to stop Hitler will be gone. 一旦俄国垮台，抑止希特勒的最后机会就没有了。