Nate held his lantern high as he came up to Olive and said: "Where is your lamp?
VOA: special.2010.01.09
So, if you use a black lamp or something and you excite something up to a higher energy level and then it relaxes back down to its lower energy state, it's going to emit a new wavelength of light, which is going to be visible to you.
如果你用一个紫外灯或别的,东西把某种分子激发到,更高的能级,然后它会掉回,到低能级,它就会释放,一个新的波长的光,这个光是可见的。
So we can figure out the energy of each photon emitted by our UV lamp by saying e is equal to h c over wavelength.
所以我们可以计算出,每个从紫外光源射出的光子,也就是e等于h乘以c除以波长。
Send these,the homeless, tempest-tost to me, I lift my lamp beside the golden door.
VOA: special.2010.05.06
Imagine I have a little lamp, a little goose- one of those little gooseneck lamps, I'd put it on the table here, I'd put the height about a f-- about a foot off the table. And if I was really good, - I could hit, or time it so that when I hurt- yeah, try again. When I turn this on switch on in the lamp, at exactly the same time, I'm going to hit a key on my computer and start it running.
想象下我有一个那种小雁颈台灯-,我把它放在桌子上,大概离桌子,有一英尺那么高吧,这样挺好的,我可以打开-,或者关闭这灯,并在这同时,我可以让我电脑,开始运行。
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