Specifically, what is going on here is the Earth's atmosphere scatters light in the blue and violet wavelength range, so the remaining wavelengths of light appear yellow.

更准确一些的说，地球大气层把蓝色和紫色的波长范围进行散射，所以光线中剩下的波长就显现出了黄色。

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In a trench dug by a University of South Florida Coastal Research Lab team, layers of oil-stained sand light up orange under ultraviolet light. Clean sand appears violet.

南佛罗里达大学海岸研究实验室的团队挖掘的一条地沟，沾了油污的沙子在紫外线下为橙色，而干净的沙子为紫色。

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The scientists needed a source of violet light, and found it in the gold nanoparticles.

因此科学家需要在金色纳米微粒中找到紫光源。

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The action of ultra-violet light from the sun on a molecule called 7-dehydrocholesterol, found in the skin, turns it into the vitamin.

ECONOMIST: Schizophrenia: Let the sun shine in | The