ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • LUNAR AND PLANETARY EXPLORATION  (9)
  • SPACE SCIENCES  (3)
  • LEIS  (2)
Sammlung
Schlagwörter
Verlag/Herausgeber
Erscheinungszeitraum
  • 1
    Digitale Medien
    Digitale Medien
    The growth mechanism of nickel in the preparation of Ni/Al2O3 catalysts studied by LEIS, XPS and catalytic activity (1994)
    Springer
    Catalysis letters 25 (1994), S. 315-324 
    Details
    ISSN: 1572-879X
    Schlagwort(e): Ni/Al2O3 catalysts ; growth mechanism ; hydrogenation of toluene ; surface characterization ; ALE ; LEIS ; ISS ; XPS
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract A series of Ni/Al2O3 catalysts prepared from vapor phase by the atomic layer epitaxy (ALE) technique have been studied. A model is proposed for the growth mechanism of nickel in its oxidic form on alumina, from sequences of treatments with Ni(acac)2 and air. In the study activity measurements were combined with surface analysis by LEIS and XPS. During the first preparation sequence (〈 5 wt% Ni) atomically dispersed nickel is obtained on the alumina support. The nickel atoms are catalytically inactive, but act as nuclei for the growth of the catalytically active Ni-species during the subsequent preparation sequences. The highest utilization of nickel atoms in the hydrogenation of toluene was obtained when the nickel nuclei were covered with one layer of active nickel species.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00816311
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 2
    Digitale Medien
    Digitale Medien
    Characterization of a Pt-Pd combustion catalyst on an alumina washcoat, with and without prior hydrothermal treatment of the washcoat (1992)
    Springer
    Catalysis letters 13 (1992), S. 27-37 
    Details
    ISSN: 1572-879X
    Schlagwort(e): Pt-Pd/alumina ; combustion catalyst ; hydrothermal treatment ; xylene oxidation ; light-off temperature ; TEM/STEM/EDS ; LEIS
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract Two Pt/Pd catalysts on cordierite monoliths were prepared by impregnating two differently treated alumina washcoats with 10 μmol [Pt+Pd] per gram catalyst in the atomic ratio Pt/Pd=4.0. Both washcoats were first thermally treated, calcined, for 2 h at 550 °C in air and one of them was additionally treated, hydrothermally, in 100% steam for 2 h at 814 °C. The hydrothermally treated catalyst was more active for complete oxidation of xylene in air: its light-off temperature was 232 °C, compared to 259 °C for the sample calcined only. To explain this higher activity, both catalysts were characterized by BET surface area, pore-size distribution, hydrogen chemisorption, X-ray diffraction, TEM/STEM/EDS and low-energy ion scattering spectroscopy (LEIS). The catalyst with a hydrothermally treated washcoat had 30% lower surface area, larger alumina crystal size, higher degree of crystallization of alumina and larger average catalyst pore size (11 nm vs. 6 nm), than the one with the washcoat, treated only thermally. The LEIS results indicated a surface enrichment of Pd on both catalysts. The Pt signal in LEIS was higher for the hydrothermally treated sample.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00770944
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 3
    facet.materialart.
    Unbekannt
    Major and trace element chemistry of Boulder 1 at Station 2, Apollo 17 (1975)
    In:  Other Sources
    Details
    Publikationsdatum: 2011-08-16
    Beschreibung: Twenty-seven samples from Boulder 1 at Station 2 are analyzed for major and trace elements by atomic absorption spectrophotometry and neutron activation analysis. Two types of matrix and several types of clast materials are characterized on the basis of their chemistry. It is shown that one matrix type is a common material at the Apollo 17 site, while the other is probably exotic to that site. The most unusual clast materials found are coarse norite (an old rock no longer found in millimeter fragments at the site) and pigeonite basalt (possibly a highland volcanic rock). It is concluded that the boulder-forming process combined materials from at least two different localities or vertical strata.
    Schlagwort(e): LUNAR AND PLANETARY EXPLORATION
    Materialart: The Moon; 14; Nov
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
  • 4
    facet.materialart.
    Unbekannt
    Major and trace element concentrations in samples from 72275 and 72255 (1974)
    In:  Other Sources
    Details
    Publikationsdatum: 2011-08-16
    Beschreibung: Analytical data have been obtained for Co, Sc, Hf, Zn, Cr, Ga, Rb, Cs, Ni, major elements, and rare earth elements in eight samples from boulder 1. The data for trace elements were obtained by radiochemical neutron activation analysis. Major elements, except Na and Mn, were obtained by atomic absorption spectral photometry. Values for Na and Mn were obtained by neutron activation analysis of the same powder that was later dissolved to provide the atomic absorption analyses.
    Schlagwort(e): SPACE SCIENCES
    Materialart: Smithsonian Astrophys. Obs. Interdisciplinary Studies of Samples from Boulder 1, Sta. 2, Apollo 17, Vol. 1; p 121-129
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
  • 5
    facet.materialart.
    Unbekannt
    Rare earths, other trace elements and iron in Luna 20 samples. (1973)
    In:  Other Sources
    Details
    Publikationsdatum: 2019-06-27
    Beschreibung: The results of the analysis by neutron activation of six samples from the Luna 20 mission and one sample of less than 1 mm fines from Apollo 16 are reported. The concentrations of the rare-earth elements (REE) in the samples of fines from Luna 20 and Apollo 16 are less than those found for corresponding materials from the mare areas but a negative Eu anomaly is still present. The concentrations of the REE in fines from Luna 20 are only about two-thirds as great as in the sample of Apollo 16 fines, but the concentration of Co, Sc and Cr are greater by factors ranging from 1.5 to 2.3.
    Schlagwort(e): SPACE SCIENCES
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
  • 6
    facet.materialart.
    Unbekannt
    A geochemical and petrographic study of 1-2-mm fines from Apollo 17 (1975)
    In:  Other Sources
    Details
    Publikationsdatum: 2019-07-13
    Beschreibung: Samples of fines less than 1-mm and 155 1-2 mm particles from several Apollo 17 sites were analyzed for Na, Sc, Cr, Mn, Fe, Co, Ni, Hf, Ta, Th, and REE. Products of comminution and construction are present in the 1-2 mm particles, and the compositions of the rock fragments clearly indicate the general chemical characteristics of their parent rock types. The likely sources of materials for the glassy particles are considered. Glasses are enriched over their parent soils in Fe, Sc, Mn, and Cr, and are relatively enriched in light REE, so that some chemical fractionation accompanies glass-forming processes. Elements were determined by instrumental neutron activation analysis.
    Schlagwort(e): LUNAR AND PLANETARY EXPLORATION
    Materialart: Lunar Science Conference; Mar 17, 1975 - Mar 21, 1975; Houston, TX
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
  • 7
    facet.materialart.
    Unbekannt
    Major and trace element compositions of matrix and aphanitic clasts from consortium breccia 73215 (1976)
    In:  Other Sources
    Details
    Publikationsdatum: 2019-07-13
    Schlagwort(e): LUNAR AND PLANETARY EXPLORATION
    Materialart: Lunar Science Conference; Mar 15, 1976 - Mar 19, 1976; Houston, TX
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
  • 8
    facet.materialart.
    Unbekannt
    Drive tube 60009 - A chemical study of magnetic separates of size fractions from five strata (1976)
    In:  Other Sources
    Details
    Publikationsdatum: 2019-07-13
    Beschreibung: Each bulk soil and both the magnetic and nonmagnetic components of the 90-150 micron and below 20 micron fractions of five soils from drive tube 60009 were analyzed. Samples were analyzed for FeO, Na2O, Sc, Cr, Co, Ni, Hf, Ta, Th, La, Ce, Sm, Eu, Tb, Yb, and Lu by neutron activation analysis. Several samples were fused and analyzed for major elements by electron microprobe analysis. Compositional variations are not systematically related to depth. The compositions of the five soils studied are well explained by a two-component mixing model whose end members are a submature Apollo 16-type soil and an extremely immature anorthositic material similar to 60025. There is evidence that the anorthositic component had received a small amount of exposure before these soils were mixed. After mixing, the soils received little exposure suggesting mixing and deposition on a rapid time scale.
    Schlagwort(e): LUNAR AND PLANETARY EXPLORATION
    Materialart: Lunar Science Conference; Mar 15, 1976 - Mar 19, 1976; Houston, TX
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
  • 9
    facet.materialart.
    Unbekannt
    Trace element distribution in mineral separates of the Allende inclusions and their genetic implications (1977)
    In:  Other Sources
    Details
    Publikationsdatum: 2019-06-27
    Beschreibung: Concentrations of the rare earth elements (REE), Sc, Co, Fe, Zn, Ir, Na, and Cr were determined for mineral separates of the coarseand fine-grained types (group I and II) of the Allende inclusions. These data in combination with other data suggest that the minerals in the coarse-grained inclusions (group I) crystallized in a closed system with respect to refractory elements although a totally molten stage is precluded. The data also indicate that fine-grained (group II) inclusions were formed by condensation from a super-cooled nebular gas; REE-rich clinopyroxene and spinel were formed earlier than REE-poor sodalite and nepheline. In addition, pre-existing Mg isotope anomalies in the coarse-grained inclusions must have been erased during the heating stage.
    Schlagwort(e): LUNAR AND PLANETARY EXPLORATION
    Materialart: Geochimica et Cosmochimica Acta; 41; Nov. 197
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
  • 10
    facet.materialart.
    Unbekannt
    Major and trace element abundances in samples from the lunar highlands (1973)
    In:  Other Sources
    Details
    Publikationsdatum: 2019-07-13
    Beschreibung: Analyses for major elements, REE, Co, Cr, Cs, Ga, Hf, Ni, Rb, Sc, and Zn have been done on samples of Apollo 16 rocks 60025, 60335, 64455, 65015, 67075, and 67629 and on fines 60601, 61221, 61241, 64501, 65701, 67601, and 69941. FeO, Na2O, REE, Co, Cr, Hf, and Sc have been determined in four 4-5 mg chips from 65015 and 20 individual, 2.5-9.5 mg fragments from 65702. It appears that trace element characteristics of small fragments are similar to those of larger rocks. No simple mixing relationship was found among KREEP basalts, VHA basalts, anorthosites, fines, and meteorites. Balances could not be simultaneously achieved for Al2O3 and LIL elements, using analyzed samples as end members for mixing models. Most samples analyzed have negative Eu anomalies, in contrast to the positive anomalies expected for plagioclase cumulates. Most samples may be derived from LIL-rich liquids that flowed into highland valleys.
    Schlagwort(e): SPACE SCIENCES
    Materialart: Lunar Science Conference; Mar 05, 1973 - Mar 08, 1973; Houston, TX
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...