ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 1975-1979  (8)
  • 1970-1974  (10)
Collection
Keywords
Years
Year
  • 1
    facet.materialart.
    Unknown
    Heterogeneities in the solar nebula (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Oxygen isotopic compositions of the high-temperature phases in carbonaceous chondrites define a mixing line with an 0-16-rich component and show little superimposed chemical isotope fractionation. Within a single inclusion in Allende, variations of delta 0-18 and delta 0-17 of 39 thousands are found. The ordinary chondrites are slightly displaced from the terrestrial fractionation trend, implying that at least 0.2 percent of the oxygen in terrestrial rocks was derived from the 0-16-rich component.
    Keywords: ASTROPHYSICS
    Type: NASA, Washington The Soviet-Am. Conf. on Cosmochem. of the Moon and Planets, Pt. 2; p 781-785
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 2
    facet.materialart.
    Unknown
    Oxygen isotope cosmothermometer. (1972)
    In:  Other Sources
    Details
    Publication Date: 2019-06-27
    Description: Variations in oxygen isotopic abundances of meteoritic minerals, chondrules, whole meteorites, and planets are discussed in terms of a model involving isotopic exchange between primordial dust and a cooling solar nebular gas. From the temperature-dependence of the isotopic fractionation factors, temperatures have been assigned to the processes of initial condensation, chondrule formation, and planetary accretion. Separated phases from carbonaceous chondrites fall into three isotopic groups representing widely differing conditions of formation: (1) low-iron olivine and pyroxene, and calcium-aluminum silicates condensed at temperatures above 1000 K; (2) high-iron olivine and pyroxene melted to form chondrules after prior cooling and exchange to temperatures of 530-620 K; and (3) hydrous silicates condensed at temperatures below 400 K.
    Keywords: INSTRUMENTATION AND PHOTOGRAPHY
    Type: Geochimica et Cosmochimica Acta; 36; Feb. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 3
    facet.materialart.
    Unknown
    Oxygen isotope temperatures of 'equilibrated' ordinary chondrites. (1972)
    In:  Other Sources
    Details
    Publication Date: 2019-06-27
    Description: Measurements have been made of O-18/O-16 ratios of coexisting minerals (plagioclase, pyroxene, olivine) from nine ordinary chondrites. The O-18 content of a given mineral increases systematically from H through L to LL group. Isotope fractionations for mineral pairs fall on a concordancy line, suggesting that these minerals were crystallized in oxygen isotope equilibrium. The isotopic temperature is estimated to be 950 (plus or minus 100) C for seven of the type 5 and type 6 chondrites.
    Keywords: SPACE SCIENCES
    Type: Geochimica et Cosmochimica Acta; 36; Feb. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 4
    facet.materialart.
    Unknown
    A component of primitive nuclear composition in carbonaceous meteorites (1973)
    In:  Other Sources
    Details
    Publication Date: 2019-06-27
    Description: Oxygen isotope analysis of anhydrous high-temperature phases from carbonaceous meteorite chondrites indicates a high degree of O(17) and O(18) isotope depletion. The isotope decay is believed to be a result of nuclear rather than chemical processes caused by the admixture of a component consisting of almost pure O(16). It is theorized that this component may predate the solar system and may represent interstellar dust with a separate history of nucleosynthesis.
    Keywords: SPACE SCIENCES
    Type: Science; 182; Nov. 2
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 5
    facet.materialart.
    Unknown
    Distribution of the pre-solar component in Allende and other carbonaceous chondrites (1977)
    In:  Other Sources
    Details
    Publication Date: 2019-06-27
    Description: Detailed analyses of separated phases of several Allende Ca-Al-rich inclusions are reported which reveal a consistent pattern of large O-16 enrichments in spinel, pyroxene, and sometimes olivine, and small O-16 enrichments in melilite, feldspathoids, and grossular. The heterogeneous distribution of the O-16 excesses, together with their enhancement in minerals believed to be early solar nebular condensates, suggests the existence of pre-solar carriers of the isotopic anomaly, probably grains or molecules with oxygen which was nearly pure O-16. Pre-solar grains of corundum or spinel, and pre-solar molecules of SiO are considered possibilities. Excess O-16, relative to terrestrial abundances, has been found in all samples of C2, C3 (the Allende is this kind), and C4 carbonaceous chondrites which have been analyzed. No direct correlation has yet been observed between the oxygen anomalies and isotope anomalies in neon, magnesium, or xenon.
    Keywords: LUNAR AND PLANETARY EXPLORATION
    Type: Earth and Planetary Science Letters; 34; 2, Ma; Mar. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 6
    facet.materialart.
    Unknown
    Oxygen isotope fractionation in Apollo 12 rocks and soils (1971)
    In:  CASI
    Details
    Publication Date: 2019-06-27
    Description: Oxygen isotopic compositions and fractionations between coexisting minerals found in lunar samples from Apollo 11 and Apollo 12 flights
    Keywords: SPACE SCIENCES
    Type: NASA-CR-114925
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 7
    facet.materialart.
    Unknown
    Loss of oxygen, silicon, sulfur, and potassium from the lunar regolith (1974)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: The processes of formation and maturation of lunar soils lead to enrichments in the heavy stable isotopes of oxygen, silicon, sulfur, and potassium. The isotopic enrichment implies substantial losses of these elements from the moon. Vaporization by micrometeorite impact and by ion sputtering have removed at least 1% of the mass of the regolith. The losses of sulfur and potassium amount to at least 20-30% of their original abundance in the regolith.
    Keywords: LUNAR AND PLANETARY EXPLORATION
    Type: Lunar Science Conference; Mar 18, 1974 - Mar 22, 1974; Houston, TX
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 8
    facet.materialart.
    Unknown
    Oxygen isotopic constraints on the composition of the moon (1974)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: The mean oxygen isotopic composition of 5 Apollo 17 soils, one Apollo 17 breccia and one Apollo 12 soil is delta O-18 = 5.63 + or - .05 and delta O-17 = 3.8 + or - .2%. These values are within several tenths of a part permil of the composition of a large fraction of the lunar interior. High-temperature condensate aggregates from Allende and other C2 and C3 chondrites are vastly enriched in O-16 compared to this composition. The moon cannot be a mixture of ordinary chondrites and Allende inclusions, nor can it be derived from such a mixture by chemical fractionation processes. The moon's isotopic composition is consistent with a mixture of high- and low-temperature condensates but the refractory fraction would have to be free of the O-16-rich component so prevalent in the meteoritic aggregates, a fact which makes such models less attractive than they once seemed.
    Keywords: LUNAR AND PLANETARY EXPLORATION
    Type: Lunar Science Conference; Mar 18, 1974 - Mar 22, 1974; Houston, TX
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 9
    facet.materialart.
    Unknown
    Genetic relations between the moon and meteorites (1975)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: The moon is shown to have an oxygen isotope distribution similar to that of the earth and the differentiated meteorites (achondrites, mesosiderites, pallasites, irons) but, according to the same criterion, the moon is unrelated to the ordinary chondrites or carbonaceous chondrites. The principal differences between the inferred chemical composition of the moon and that of chondritic meteorites is the depletion of volatile and semivolatile elements, the enrichment of uranium by a factor of 10-15, and the enrichment of the source regions of mare basalts in LIL elements by a factor of 5-10. The reported data support the theory that the moon was formed by the capture of differentiated meteorites. Volatile-element depletion and 'refractory' element enrichment are considered.
    Keywords: LUNAR AND PLANETARY EXPLORATION
    Type: Lunar Science Conference; Mar 17, 1975 - Mar 21, 1975; Houston, TX
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 10
    facet.materialart.
    Unknown
    Consortium investigation of breccia 67435 (1976)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: The paper presents results of the initial phase of a consortium investigation of lunar rock 67435, a glass coated breccia which contains a unique spinel-troctolite clast. These results include oxygen isotopic data for the host breccia, bulk composition data for the host breccia, glass coating and a large aphanitic clast, and detailed petrographic descriptions of all lithologies encountered.
    Keywords: LUNAR AND PLANETARY EXPLORATION
    Type: Lunar Science Conference; Mar 15, 1976 - Mar 19, 1976; Houston, TX
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...