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molecular clouds

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Journal Article
Published: 01 January 2008
Reviews in Mineralogy and Geochemistry (2008) 68 (1): 55-72.
...Adam G. Jensen; F. Markwick-Kemper; Theodore P. Snow Abstract The oxygen that is observed in the Solar System today is a remnant of the interstellar oxygen that was in the dense molecular cloud that collapsed to form the Solar System. While the chemical evolution of the Galaxy has progressed since...
Journal Article
Journal: Elements
Published: 01 April 2018
Elements (2018) 14 (2): 101-106.
...Hikaru Yabuta; Scott A. Sandford; Karen J. Meech Abstract Organic molecules and volatiles (e.g. H 2 O, CO, CO 2 ) are the major components of comets. The majority of the organic compounds found within comets were produced by ice irradiation in dense molecular clouds and in the protoplanetary disk...
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Journal Article
Journal: Elements
Published: 01 February 2011
Elements (2011) 7 (1): 23-28.
...Douglas Rumble, III; Edward D. Young; Anat Shahar; Weifu Guo Abstract Stable isotopes record the evolution of planetary systems, beginning with stars coalescing from molecular clouds, followed by the nucleosynthesis of elements in stars, and proceeding to the accretion and differentiation...
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Journal Article
Published: 01 November 2008
American Mineralogist (2008) 93 (11-12): 1693-1720.
...Robert M. Hazen; Dominic Papineau; Wouter Bleeker; Robert T. Downs; John M. Ferry; Timothy J. McCoy; Dimitri A. Sverjensky; Hexiong Yang Abstract The mineralogy of terrestrial planets evolves as a consequence of a range of physical, chemical, and biological processes. In pre-stellar molecular...
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Journal Article
Published: 01 January 2008
Reviews in Mineralogy and Geochemistry (2008) 68 (1): 187-218.
... the disk at high incident angles causes a similar horizon of CO photodestruction. Variations in 16 O could also have been inherited from self-shielding by CO in the molecular cloud that gave rise to the protosun. The overall consequence of CO self-shielding is conversion of CO gas to 16 O-poor H 2 O. A key...
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Journal Article
Journal: Elements
Published: 01 August 2010
Elements (2010) 6 (4): 223-228.
...Guenter Engling; András Gelencsér Abstract Atmospheric brown clouds are atmospheric accumulations of carbonaceous aerosol particles spanning vast areas of the globe. They have recently gained much attention, from the scientific community and from the general population, as they severely impact...
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Series: Geological Society, London, Special Publications
Published: 01 January 2004
DOI: 10.1144/GSL.SP.2004.237.01.04
EISBN: 9781862394858
... Abstract Over the past 10 years, investigations into the characteristics of the high molecular weight hydrocarbon (HMWHC) fraction in crude oils and, to a lesser extent, source rock extracts have continued to reveal novel information concerning the distribution of hydrocarbons >C 40...
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Journal Article
Published: 01 January 2006
Reviews in Mineralogy and Geochemistry (2006) 61 (1): 127-180.
... by multiplying by the molecular weight. Other magnetic balances apply similar principles and by the addition of Dewar and heating coil systems, susceptibility can be studied as a function of temperature and Curie and Néel points can be determined. In the case of ferri- or ferromagnetic materials...
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Journal Article
Published: 01 January 2006
Reviews in Mineralogy and Geochemistry (2006) 61 (1): 231-264.
... on molecular orbital and band theories, although for transition metal sulfides, the ligand (or crystal) field theories have also provided useful insights. Atomistic modeling, a quantitative approach developed from the ionic view has also, perhaps surprisingly, proved useful for certain applications...
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Journal Article
Published: 01 January 2006
Reviews in Mineralogy and Geochemistry (2006) 61 (1): 181-229.
... in molecular units. In infrared spectroscopy in its simplest forms, infrared light is passed through a sample (gas, liquid, powdered solid or single crystal) and its selective absorption measured as a function of the wavelength of that light. Reflection of infrared light from a powder or polished crystal...
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Journal Article
Published: 01 January 2006
Reviews in Mineralogy and Geochemistry (2006) 61 (1): 505-556.
... on sulfide mineral surfaces where cleavage quality is poor. Surface or step edge stoichiometry can be altered to attain charge neutrality and stability by forming vacancies. Formation energies for neutral vacancies in sulfide minerals can be addressed using molecular modeling approaches, but they can also...
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Journal Article
Journal: Clay Minerals
Published: 01 March 2019
Clay Minerals (2019) 54 (1): 49-56.
.... Adsorption complexes of the 5-ASA conformers (a) F1 and (b,c) F2 on the kaolinite siloxane surface optimized with (a,b) CVFFH and with (c) DFT. Fig. 2. Molecular structure of 5-ASA optimized with CVFFH, conformers (a) F1, (b) F2 and (c) the anion form F3. The H, C, O, N and Na atoms are in white...
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Journal Article
Published: 01 January 2017
Reviews in Mineralogy and Geochemistry (2017) 82 (1): 27-63.
... can be related to the difference in the Helmholtz free energy of the pure isotopomers ( AX′, AX, BX′ and BX ): The Helmholtz free energy is related to the molecular partition function, Q by : (5) β A X = ( m ′ m ) 3 2 × ( M M...
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Journal Article
Published: 01 August 2016
Clays and Clay Minerals (2016) 64 (4): 389-400.
... of practical and inexpensive decontamination techniques. In this work, molecular dynamics simulations were carried out to determine the thermodynamics of Cs + adsorption at the basal surface of six 2:1 phyllosilicate minerals, namely pyrophyllite, illite, muscovite, phlogopite, celadonite, and margarite...
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Journal Article
Published: 01 November 2018
Reviews in Mineralogy and Geochemistry (2018) 84 (1): 57-83.
... ). These findings are crucial for understanding droplet nucleation phenomena in water vapor, aerosols, clouds and atmospheric chemistry processes occurring at the nanodroplet interior and surfaces. The interpretation of mass spectrometric and IRMPD spectra builds critically on results from molecular simulations...
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Journal Article
Published: 01 January 2009
Bulletin de la Société Géologique de France (2009) 180 (1): 39-43.
...Gareth Nelson; Pauline Y. Ladiges Abstract In molecular dating, branch lengths are considered parameters that may be estimated by counting similarities and differences in DNA sequences. Long and short branches imply long and short time spans, which might appear informative additions when imposed...
Journal Article
Published: 01 January 2001
Reviews in Mineralogy and Geochemistry (2001) 42 (1): 485-531.
... was approximated by a finite basis set wavefunction Φ′ . The wavefunction Φ′ may be, as another layer of approximation, separated into a product of functions dependent only on coordinates of a single electron. These single electron coordinate functions are called “molecular orbitals” Ψ i and may...
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Journal Article
Published: 01 January 2001
Reviews in Mineralogy and Geochemistry (2001) 42 (1): 199-271.
... of this approach for geoscience applications. It is the principal goal of this review to demonstrate the methodological application and the utility of molecular modeling techniques for fundamental studies of semiconducting mineral surfaces. Essential background material pertaining to the physics and chemistry...
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Journal Article
Published: 01 January 2000
Reviews in Mineralogy and Geochemistry (2000) 41 (1): 335-419.
... pressure data (a general feature of many molecular systems, as discussed above for the rare gas solids). More recently, the data have been examined using additional phenomenological equation of state formulations ( Cohen et al. 2000 ) ( Fig. 6a ). As shown in the first synchrotron measurements to 26.5 GPa...
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Series: Geological Society, London, Special Publications
Published: 01 January 2013
DOI: 10.1144/SP380.7
EISBN: 9781862396456
... for a range of ashes and their mineral and rock components. An irony of remote sensing is that often properties of the target need to be known to make full use of the remote measurement. In the case of gaseous species this is the molecular spectroscopy of the target gas. For aerosol or cloud, a priori...
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