Results 31 to 40 of about 6,446,269 (330)
Planet-forming material in a protoplanetary disc: the interplay between chemical evolution and pebble drift [PDF]
Monthly notices of the Royal Astronomical Society, 2019 The composition of gas and solids in protoplanetary discs sets the composition of planets that form out of them. Recent chemical models have shown that the composition of gas and dust in discs evolves on Myr time-scales, with volatile species ...
Richard A. Booth, J. Ilee
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Stellar Chemical Evolution [PDF]
Symposium - International Astronomical Union, 1997 One of the major achievements of astrophysics has been the demonstration that most of the chemical elements have been synthesized in stars: nucleosynthesis calculations of homogeneous and inhomogeneous big bang cosmologies show that, in comparison with the most metal-poor stars currently known, essentially no elements heavier than B existed at the era ...
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Filozofia i NaukaThe article presents the hypothesis of the origin of life. All the basic ideas of the 20th century research program in this area can be found there: the extrapolation of Darwinism into the area of chemical evolution, the influence of solar energy, the ...
Richard Krzymowski
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, 2008 In this series of lectures we first describe the basic ingredients of galactic chemical evolution and discuss both analytical and numerical models. Then we compare model results for the Milky Way, Dwarf Irregulars, Quasars and the Intra-Cluster- Medium with abundances derived from emission lines.
Horst Rauchfuss, Terence N. Mitchell
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Life, 2022 The RNA world hypothesis suggests that chemical networks consisting of functional RNA molecules could have constructed a primitive life-like system leading a first living system.
Kunio Kawamura +8 more
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First results from the IllustrisTNG simulations: a tale of two elements - chemical evolution of magnesium and europium [PDF]
, 2017 The distribution of elements in galaxies provides a wealth of information about their production sites and their subsequent mixing into the interstellar medium. Here we investigate the distribution of elements within stars in the IllustrisTNG simulations.
J. Naiman +11 more
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Galactic Chemical Evolution of Radioactive Isotopes [PDF]
Astrophysical Journal, 2019 The presence of short-lived (∼Myr) radioactive isotopes in meteoritic inclusions at the time of their formation represents a unique opportunity to study the circumstances that led to the formation of the solar system.
Benoit Côté +6 more
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Some Terpenes and Related Derivatives Synthesized in Cold Plasma Systems
Molecules, 1997 The synthesis of bicyclo-[2.2.1]-heptane and bicyclo-[7.2.0]-undec-4-ene derivatives under cold plasma conditions are reported. The reaction systems involve gaseous mixtures at an interface with ice surfaces.
Cristofor I. Simionescu +3 more
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Biology Direct, 2012 Background Our current understanding of evolution is so tightly linked to template-dependent replication of DNA and RNA molecules that the old idea from Oparin of a self-reproducing 'garbage bag' ('coacervate') of chemicals that predated fully-fledged ...
Vasas Vera +4 more
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Traits for chemical evolution in solar twins [PDF]
Astronomy & Astrophysics, 2019 The physical processes driving chemical evolution in the Milky Way can be probed using the distribution of abundances in low-mass FGK type stars in space phase at different times.
P. Jofré, Holly Jackson, M. T. Maia
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