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The Natural History of Oxygen
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 discu...
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Formato: | Texto |
Lenguaje: | English |
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The Rockefeller University Press
1965
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2195461/ https://www.ncbi.nlm.nih.gov/pubmed/5859927 |
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author | Dole, Malcolm |
author_facet | Dole, Malcolm |
author_sort | Dole, Malcolm |
collection | PubMed |
description | 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. |
format | Text |
id | pubmed-2195461 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 1965 |
publisher | The Rockefeller University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-21954612008-04-23 The Natural History of Oxygen Dole, Malcolm J Gen Physiol Structure and Function of Oxygen 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. The Rockefeller University Press 1965-09-01 /pmc/articles/PMC2195461/ /pubmed/5859927 Text en Copyright © 1965 by The Rockefeller University Press This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/). |
spellingShingle | Structure and Function of Oxygen Dole, Malcolm The Natural History of Oxygen |
title | The Natural History of Oxygen |
title_full | The Natural History of Oxygen |
title_fullStr | The Natural History of Oxygen |
title_full_unstemmed | The Natural History of Oxygen |
title_short | The Natural History of Oxygen |
title_sort | natural history of oxygen |
topic | Structure and Function of Oxygen |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2195461/ https://www.ncbi.nlm.nih.gov/pubmed/5859927 |
work_keys_str_mv | AT dolemalcolm thenaturalhistoryofoxygen AT dolemalcolm naturalhistoryofoxygen |