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搜索结果: 1-4 共查到国际动态 理学 atmospheric oxygen相关记录4条 . 查询时间(0.122 秒)
Oxygen first accumulated in the Earth's atmosphere about 2.4 billion years ago, during the Great Oxidation Event. A long-standing puzzle has been that geologic clues suggest early bacteria were photos...
Variations in the amount of oxygen in Earth's atmosphere significantly altered global climate throughout the planet's history. Efforts to reconstruct past climates must include this previously overloo...
The period of extended low oxygen, which spanned from roughly 2 to less than 1 billion years ago, was a time of remarkable chemical stability in the Earth's oceans and atmosphere. A University of Cali...
November 29, 2006,PASADENA, Calif.--Two and a half billion years ago, when our evolutionary ancestors were little more than a twinkle in a bacterium's plasma membrane, the process known as photosynthe...

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