NO2 is the main source of nitrate aerosols, which form an important fraction of PM2.5 and, in the presence of ultraviolet light, of ozone.

二氧化氮是硝酸盐气溶胶的主要来源，构成PM 2.5和在紫外线下臭氧的主要部分。

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In years past, spicules had been judged too cool to be a source of the high temperature plasma that, among other things, generates the sun's ultraviolet light.

过去，人们认为针状体的温度太低，除了产生太阳的紫外线，并不足以作为高温等离子体的发射源。

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Harmful ultraviolet rays cause 90 percent of skin damage [source: Poirot].

紫外线极具杀伤力，足以引起皮肤90%的损坏【Poirot研究中心】。

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