科学为什么·英语30篇（1）

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为什么某些岩石在紫外线下会发光？

Some minerals, like fluorite and calcite, absorb invisible ultraviolet light and re-emit it as visible light.
This process is called fluorescence, and it occurs because electrons in the mineral get excited by UV energy.
When those electrons return to their normal state, they release energy as colored light we can see.
The color depends on the mineral’s chemical composition and crystal structure, not on its surface appearance.
Not all rocks glow—only those containing specific trace elements like manganese or rare-earth metals do so.
Fluorescence helps geologists identify minerals quickly in the field without using complex lab equipment.
Sunlight contains a small amount of UV, but stronger artificial UV lamps make the effect much clearer.
Unlike bioluminescence, this glow stops immediately when the UV source is removed.
Scientists also use this property to detect mineral deposits underground using airborne UV sensors.
Even ancient Roman builders unknowingly used fluorescent limestone in some temples that shimmered faintly in daylight.

听 → 读 → 学表达 → 懂 → 今天会说这一句 → 跟读录音 → 自己说一句。

Unlike bioluminescence, this glow stops immediately when the UV source is removed. 与生物发光不同，一旦移除紫外光源，荧光立即消失。
Fluorescence helps geologists identify minerals quickly in the field without using complex lab equipment. 荧光帮助地质学家在野外快速识别矿物，无需复杂实验室设备。
Scientists also use this property to detect mineral deposits underground using airborne UV sensors. 科学家还利用该特性，通过机载紫外传感器探测地下矿藏。

这篇中文题目最接近哪一句？为什么某些岩石在紫外线下会发光？一次学校运动会的通知一份超市购物清单

课文第一句的意思更接近？某些矿物（如萤石和方解石）能吸收不可见的紫外光，并将其重新发射为可见光。今天学校放假了。请把窗户打开。

这一课主要在讲什么？（看英文标题） Why Do Certain Rocks Glow Under Ultraviolet Light? How to cook noodles A maths worksheet

Unlike bioluminescence, this glow stops immediately when the UV source is removed.

Unlike bioluminescence, this glow stops immediately when the UV source is removed.

第一版：录下来、回听、再听标准音。系统打分以后再加。

用今天的表达，自己说一句。

例子：Unlike bioluminescence, this glow stops immediately when the UV source is removed.