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超级老快

木虫之王 (文学泰斗)

[求助] 求汉译英两句话,谢谢大家!

在众多的稀土发光离子中,Eu掺杂的发光材料由于优良的荧光特性在照明与显示方面占据着非常重要的科研地位。Eu原子以Eu3+和Eu2+两种离子形式存在与化合物中,Eu3+的发光是由一系列位于红光区域的尖锐发射峰组成, 这些发射峰对应着4f-4f产能级的跃迁,因此发射峰的位置几乎不受晶体场影响。另一方面,对于Eu2+的发光为宽带发射,发射带来自于4f5d-4f的跃迁,由于最外层电子没有被屏蔽,因此,发射带的位置及宽度强烈依赖基质的共价性、阳离子半径大小以及晶场力大小变化,从而发光可从紫光变到红光区域。
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genhunter

至尊木虫 (著名写手)

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超级老快: 金币+70, 翻译EPI+1, ★★★很有帮助 2016-08-17 21:29:57
Europium-doped luminescent materials are unique among many other rare earth ion-doped luminescent materials in their excellent fluorescent properties, and hold very important roles in research and development in areas of lighting and image display. Europium is found in chemicals in two types: Eu3+ and Eu2+.  The light emitted by Eu3+ is composed of a series of sharp emission peaks in red spectrum, which correspond to 4f-4f energy level transitions. Consequently, the frequency of the emission is hardly influenced by the nearby crystalline field. On the other hand, the light emission from Eu2+ originated from 4f5d-4f level transitions covers a broad spectrum. Since the electrons in the outmost layer are unshielded, the frequency of light emitted and the bandwidth are strongly dependent on the covalency ofthe matrix,  the radius of cations,  and the strength of crystalline field. As a result, the spectrum vary from violet to red.
离成功还差一点
2楼2016-08-17 21:12:10
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