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Chemical Evolution of Galaxies
Annual Review of Astronomy and Astrophysics, 1976The various nucleosynthetic processes needed to account for the formation of the different nuclear species have been described in the previous chapters as well as the location of these nucleosynthetic events. At the beginning of this monograph, the evolution of the matter which constitutes the celestial bodies such as planets, stars and galaxies was ...
Audouze, J., Tinsley, B.M.
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Chemical Evolution of the Galaxy
Annual Review of Astronomy and Astrophysics, 1991Since the discovery of the cosmic microwave background ( 1 84), it is gen erally assumed that the universe originated from a hot big bang (78). Detailed nucleosynthesis calculations based on the hot big bang model (e.g. 4, 1 82, 221 ) showed that no element heavier than 9Be could have been synthesized primordially with an abundance exceeding 101 4 by ...
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Chemical evolution of photosynthesis
Origins of Life, 1976The principles of biological evolution of photosynthesis are established, but the ways of chemical evolution are unclear yet. The model systems will help to elucidate the problem. Every type of photosynthesis requires photoreceptor absorbing solar radiation. We studied as photoreceptors inorganic components of Earth crust, some coenzymes and porphyrins
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The role of phosphorus in chemical evolution
Chemical Society Reviews, 2005AbstractFor Abstract see ChemInform Abstract in Full Text.
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Chemical Evolution and the Origin of Life
Nature, 1964Theory and experimental program in support of chemical approach to life origin and ...
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Pathways of Chemical Evolution of Photosynthesis
Origins of Life, 1974The primary metabolism of protobionts was probably based on the electron transfer reactions regulated by catalysts or photosensitizing pigments. The action of photoreceptive pigments was inevitable in the case of electron transfer leading to light energy storage in the reaction products.
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1997
Even if we take a ‘replicators first’ view of the origin of life, we still have to explain how a chemical environment arose that was sufficiently diverse for such replicators to be formed. As a minimum, we must explain the abiotic formation of sugars and amino acids, and of nucleotides or of some simpler molecules capable of base pairing, and hence of ...
John Maynard Smith, Eors Szathmary
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Even if we take a ‘replicators first’ view of the origin of life, we still have to explain how a chemical environment arose that was sufficiently diverse for such replicators to be formed. As a minimum, we must explain the abiotic formation of sugars and amino acids, and of nucleotides or of some simpler molecules capable of base pairing, and hence of ...
John Maynard Smith, Eors Szathmary
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Early Years Educator, 2008
Thankfully, the vast majority of parents want the very best for their children. However, many will be unaware of the hidden dangers that many baby care products carry for even the youngest babies.
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Thankfully, the vast majority of parents want the very best for their children. However, many will be unaware of the hidden dangers that many baby care products carry for even the youngest babies.
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The evolution of the chemical isotopes as an analog of biological evolution
Journal of Theoretical Biology, 1980Abstract A comparison is made between a biological adaptive landscape and the chemical isotopic landscape defined with three dimensions: the number of protons, the number of neutrons, and the stability of each isotopic nucleus. The courses of both biological and elemental evolution have been stochastic, leading from the simple to the complex; this is
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