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pro vyhledávání: '"Roger G. Burns"'
Autor:
Roger G. Burns
Publikováno v:
Perovskite: A Structure of Great Interest to Geophysics and Materials Science
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::0166ce402a22edee5a9737115d5c65ab
https://doi.org/10.1029/gm045p0081
https://doi.org/10.1029/gm045p0081
Publikováno v:
Meteoritics. 30:625-633
— Mossbauer spectroscopy is a very useful tool for identifying ferric iron weathering products in meteorites because of the capability to quantify the relative amounts of ferric iron in them. Mossbauer measurements were made of 33 Antarctic H chond
Autor:
Roger G. Burns
Publikováno v:
Hyperfine Interactions. 91:739-745
The variety of coordination numbers, symmetries, distortions and ligand environments in thermally-stable iron-bearing minerals provide wide ranges of chemical shift (δ) and quadrupole splitting (δ) parameters, which serve to characterize the crysta
Autor:
Roger G. Burns, Duncan S. Fisher
Publikováno v:
Hyperfine Interactions. 91:571-576
Determination of oxidation states and the crystal chemistry of iron-bearing minerals in carbonaceous chondrites by Mossbauer spectroscopy is complicated by thermally-induced electron-hopping in cronstedtite, superparamagnetism of hydrous ferric oxide
Autor:
Roger G. Burns
Publikováno v:
Geochimica et Cosmochimica Acta. 57:4555-4574
Ferric-bearing assemblages on Mars indicate that oxidative weathering of surface basalts has occurred during the evolution of the Red Planet. In aqueous environments chemical weathering proceeded through stages of dissolution of Fe 2+ -bearing silica
Autor:
Roger G. Burns
Publikováno v:
Geochimica et Cosmochimica Acta. 57:4551-4554
The topics covered with respect to chemical weathering on Mars include the following: Mars soil, mineralogy, spectroscopic analysis, clays, silicates, oxidation, iron oxides, water, chemical reactions, geochemistry, minerals, Mars atmosphere, atmosph
Publikováno v:
Geochimica et Cosmochimica Acta. 57:4583-4595
Spectroscopic analyses show that Fe(3+)-doped smectites prepared in the laboratory exhibit important similarities to the soils on Mars. Ferrihydrite has been identified as the interlayer ferric component in Fe(3+)-doped smectites by a low quadrupole
Autor:
Roger G. Burns
Publikováno v:
Mineralogical Applications of Crystal Field Theory. :470-474
Autor:
Marilyn M. Lindstrom, Ludolf Schultz, E. S. Michlovich, S. Vogt, Derek W. G. Sears, John F. Wacker, Duncan S. Fisher, Cecilia Satterwhite, T. Loeken, David W. Mittlefehldt, P. Scherer, Michael E. Zolensky, Michael E. Lipschutz, Roger G. Burns, Paul H. Benoit, Stephen F. Wolf, R.T. Dodd
Publikováno v:
Meteoritics. 28:528-537
The Noblesville meteorite is a genomict, regolith breccia (H6 clasts in H4 matrix). Moessbauer analysis confirms that Noblesville is unusually fresh, not surprising in view of its recovery immediately after its fall. It resembles 'normal' H4-6 chondr
Autor:
Duncan S. Fisher, Roger G. Burns
Publikováno v:
Journal of Geophysical Research: Planets. 98:3365-3372
A model of acid weathering is proposed for the iron-rich basalts on Mars. Aqueous oxidation of iron sulfides released SO4(2-) and H(+) ions that initiated the dissolution of basaltic ferromagnesian silicates and released Fe(2+) ions. The Fe(2+) ions