The sweat fingerprint left on them can not be photographed directly because it cannot be seen by naked eyes due to sweat's volatilization and object's permeability.

由于汗液的挥发性和客体的渗透性，部分的汗液挥发到空气中或是渗透到客体中，无色的汗液手印很难用肉眼观察到，因此难以进行直接拍照。

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Photographed Baby Do not forget to leave when receiving mail! The two sides at the same time-line can be directly Wang Wang; QQ Shipping!

拍下宝贝时千万别忘记了留下收货邮箱！ 双方同时在线就可以直接用旺旺；QQ发货！

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The far hemisphere was first photographed by the Soviet Luna 3 probe in 1959, and was first directly observed by human eyes when the Apollo 8 mission orbited the Moon in 1968.

这个远处的半球第一次是在1959年由苏联月神3好宇宙飞船探测器拍摄到的，而且它第一次被人类肉眼发现是在1968年阿波罗8号环绕月球时出现的。

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