Results 11 to 20 of about 367,412 (259)
Reactions of Graphene Nano-Flakes in Materials Chemistry and Astrophysics
Physchem, 2022 The elucidation of the mechanism of the chemical evolution of the universe is one of the most important themes in astrophysics. Polycyclic aromatic hydrocarbons (PAHs) provide a two-dimensional reaction field in a three-dimensional interstellar space ...
Hiroto Tachikawa, Tetsuji Iyama
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Origin of Life: The Point of No Return
Life, 2020 Origin of life research is one of the greatest scientific frontiers of mankind. Many hypotheses have been proposed to explain how life began. Although different hypotheses emphasize different initial phenomena, all of them agree around one important ...
Dimiter Kunnev
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Universe, 2022 In this paper, we make use of data collected for open cluster members by high-resolution spectroscopic surveys and programmes (i.e., APOGEE, Gaia-ESO, GALAH, OCCASO, and SPA). These data have been homogenised and then analysed as a whole.
Lorenzo Spina +2 more
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Volatile Organic Compounds of Bryophytes from Peninsular Malaysia and Their Roles in Bryophytes
Plants, 2022 Volatile emissions from 22 bryophyte species from Peninsular Malaysia were collected using a dynamic headspace technique and analyzed by gas chromatography–mass spectrometry (GC-MS).
Chin Wen Koid +9 more
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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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, 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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THE PROTOBIOLOGICAL THEORY OF CEILINGS AND FLOORS, OR CHEMICAL EVOLUTION AS A PLANETARY PROCESS [PDF]
Filozofia i NaukaThe article presents a modern protobiological theory based on the classical archetype. It connects the issues of origins of life with the theory of the hierarchy of matter and recognizes that error correction occurs within hierarchical and dynamic living
Alicja Kubica
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Origin of the Reductive Tricarboxylic Acid (rTCA) Cycle-Type CO2 Fixation: A Perspective
Life, 2017 The reductive tricarboxylic acid (rTCA) cycle is among the most plausible candidates for the first autotrophic metabolism in the earliest life. Extant enzymes fixing CO2 in this cycle contain cofactors at the catalytic centers, but it is unlikely that ...
Norio Kitadai +2 more
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Prebiotic Chemistry: Geochemical Context and Reaction Screening
Life, 2013 The origin of life on Earth is widely believed to have required the reactions of organic compounds and their self- and/or environmental organization. What those compounds were remains open to debate, as do the environment in and process or processes by ...
Henderson James Cleaves
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Molecular Asymmetry in Prebiotic Chemistry: An Account from Meteorites
Life, 2016 Carbonaceous Chondrite (CC) meteorites are fragments of asteroids, solar planetesimals that never became large enough to separate matter by their density, like terrestrial planets.
Sandra Pizzarello
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