Dole M
J Gen Physiol. 1965 Sep;49(1):Suppl:5-27. doi: 10.1085/jgp.49.1.5.
The nuclear reactions occurring in the cores of stars which are believed to produce the element oxygen are first described. Evidence for the absence of free oxygen in the early atmosphere of the earth is reviewed. Mechanisms of creation of atmospheric oxygen by photochemical processes are then discussed in detail. Uncertainty regarding the rate of diffusion of water vapor through the cold trap at 70 km altitude in calculating the rate of the photochemical production of oxygen is avoided by using data for the concentration of hydrogen atoms at 90 km obtained from the Meinel OH absorption bands. It is estimated that the present atmospheric oxygen content could have been produced five to ten times during the earth's history. It is shown that the isotopic composition of atmospheric oxygen is not that of photosynthetic oxygen. The fractionation of oxygen isotopes by organic respiration and oxidation occurs in a direction to enhance the O(18) content of the atmosphere and compensates for the O(18) dilution resulting from photosynthetic oxygen. Thus, an oxygen isotope cycle exists in nature.
首先描述了恒星核心中发生的被认为会产生氧元素的核反应。回顾了地球早期大气中不存在游离氧的证据。然后详细讨论了通过光化学过程产生大气氧的机制。通过使用从迈内尔OH吸收带获得的90公里处氢原子浓度数据，避免了在计算光化学产氧速率时水蒸气通过70公里高度冷阱扩散速率的不确定性。据估计，在地球历史上，目前的大气氧含量可能已经产生了五到十倍。结果表明，大气氧的同位素组成并非光合氧的同位素组成。有机呼吸和氧化过程中氧同位素的分馏发生的方向是增加大气中的O(18)含量，并补偿光合氧导致的O(18)稀释。因此，自然界中存在一个氧同位素循环。
