Results 201 to 210 of about 10,798 (236)

RAMAN-GEOTHERMOMETER FOR CARBONACEOUS CHONDRITES

Доклады Российской академии наук. Физика, технические науки, 2023
Samples of the Murchison meteorite (carbonaceous chondrite, type CM2) were kept isothermally in a specially designed device at temperatures of 200, 500 and 800°C. After the samples cooled down in an inert helium atmosphere, Raman scattering spectra were taken.
S. A. Voropaev, A. P. Krivenko, N. V. Dushenko   +2 more
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Amino acids in carbonaceous chondrites

Origins of Life, 1974
For almost 20 years laboratory experiments have advanced the concepts of chemical evolution, particularly with regard to formation of the amino acids. What has been generally lacking is concrete natural evidence for this chemical evolution hypothesis.
J G, Lawless, E, Peterson
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Deuterium in carbonaceous chondrites

Earth and Planetary Science Letters, 1980
Hydrogen isotopic compositions in seven carbonaceous chondrites lie in the range -70 to +771 per thousand relative to standard mean ocean water. These values decrease, to a range from -145 to +219 per thousand, after low-temperature oxidation in an oxygen plasma.
Y KOLODNY, J KERRIDGE, I KAPLAN
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Xenon in Carbonaceous Chondrites

Nature Physical Science, 1972
Carbonaceous chondrites contain two isotopically distinct components of trapped xenon which cannot be explained by the occurrence of nuclear or fractionation processes within these meteorites.
O. K. MANUEL, E. W. HENNECKE, D. D. SABU
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Matrices of Carbonaceous Chondrite Meteorites

Annual Review of Earth and Planetary Sciences, 1993
The morphology, classification, and chemistry of the matrices of carbonaceous chondrite (CC) meteorites is reviewed based on recent research results. The various kinds of CCs are examined in terms of their matrix mineralogy. Alteration processes in CCs are discussed.
P R Buseck, X Hua
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The ultraviolet spectra of carbonaceous chondrites

Celestial Mechanics and Dynamical Astronomy, 1992
Optical spectroscopy of meteorites is an important laboratory tool for the study of the origin and evolution of solar and galactic interstellar minor bodies. In the region from the visible to the ultraviolet, the absorption spectra have hitherto been measured on the Bruderheim (Egan and Hilgeman, 1975), the Orgueil (Huffman, 1977), the Murchison ...
T. Inagaki, S. Yabushita, K. Wada
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Carbonaceous chondrites as bioengineered comets

SPIE Proceedings, 2012
The discovery of microfossils on carbonaceous meteorites has electrified the public with the first concrete evidence of extraterrestrial biology. But how these organisms colonized and grew on the parent body–the comet–remains a mystery. We report on several features of cyanobacteria that permit them to bioengineer comets, as well as a tantalizing ...
Robert B. Sheldon, Richard Hoover
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Organic Matter in Carbonaceous Chondrites

1986
Carbonaceous chondrites are objects of great interest for chemists and astrophysicists. They contain a large number of abiogenic organic molecules and they are fragments of the least metamorphized bodies which exist in the solar system. Therefore, the study of carbonaceous chondrites affords information about the state of matter 4.5 Gyr ago.
Françoise Mullie, Jacques Reisse
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Boron in Carbonaceous Chondrites

Nature, 1968
BORON is remarkable in that its compounds are common and inexpensive although the element occurs quite low on the cosmic abundance scale, alongside lithium and beryllium. The cosmic scarcity of these three light elements is related to the ease with which their nuclei are disintegrated during nucleogenesis, whereas the terrestrial familiarity of borates
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