By studying bacteria that flourish in the oxygen-free water, scientists hope, among other things, to learn how simple life-forms can lead to more complex ones.
通过研究这些生活在无氧环境下细菌，科研人员希望了解这些简单的生物是如何进化成更为复杂的生物的。
It is the only planet known to have an atmosphere containing free oxygen, oceans of liquid water on its surface, and, of course, life.
也是我们已知的唯一拥有含氧大气、表层液态水海洋以及生命的星球。
The formation of heavy oil reservoirs is chiefly controlled by late uplifting of the basin, biodegradation, water-washing, and free oxygen oxidizing.
重质稠油藏的形成主要受盆地后期抬升活动、生物降解、地层水洗和氧化作用等因素控制。
The reaction related to the method of the invention needs no strict water-free and oxygen-free conditions, occurs smoothly in the air and is easy to operate;
本发明方法所涉及的反应不需要严格的无水无氧条件，在空气中即可顺利发生， 操作方便简单；
The reaction related to the method of the invention needs no strict water-free and oxygen-free conditions, occurs smoothly in the air and is easy to operate;
本发明方法所涉及的反应不需要严格的无水无氧条件，在空气中即可顺利发生， 操作方便简单；
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