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Molybdenum isotope

Henrich and WolP have studied the formation of Mo(CO)5 by catching Mo and Mo recoils in Cr(CO)g. The Molybdenum isotopes were produced in several different reactions, so that the recoil energy varied over a wide range. It was found that the yields of Mo(CO)g with the two isotopes differed from each other, but varied only slightly as a function of initial recoil energy. These authors were also able to show that the isotope effect of about 8% is nearly insensitive to radiation received by the sample (and catcher) during the bombardment. They argued that there remains only one possible cause of this isotope effect, that is, differences in the de-excitation schemes of the product nuclei. [Pg.79]

Arnold, G.L., Anbar, A.D., Barling, J. and Lyons, T.W. (2004). Molybdenum isotope evidence for widespread anoxia in mid-Proterozoic oceans. Science, 304, 87-90... [Pg.33]

Molybdenum isotope variations appear to be on the order of 3.5%o in Mo/ Mo ratios, where the largest fractionation is seen between aqueous Mo in seawater and that incorporated in Fe-Mn crusts and nodules on the seafloor (Chapter 12 Anbar 2004). This isotopic contrast is interpreted to reflect fractionation by Mo sorption to Mn oxide-rich sediments relative to aqueous Mo. The 5 Mo values for euxinic sediments in turn are distinct from those of Fe-Mn crusts, highlighting the isotopic contrasts between major repositories of Mo in surface and near-surface environments. As discussed by Anbar (2004) in Chapter 12, a major focus of research on Mo isotopes has been the potential use as a paleoredox indicator in marine systems. [Pg.12]

Barling J, Anbar AD (2004) Molybdenum isotope fractionation during adsorption by manganese oxides. Earth Planet Sci Lett 217 315-329... [Pg.22]

Nicolussi GK, Pellin MJ, Lewis RS, Davis AM, Amari S, Clayton RN (1998a) Molybdenum isotopic composition of individual presolar silicon carbide grains from the Murchison meteorite. Geochim Cosmochim Acta 62 1093-1104... [Pg.61]

Russel WA, Papanastassiou DA, Tomhrello TA (1978) Ca isotope fractionation on the Earth and other solar system materials. Geochim Cosmochim Acta 42 1075-1090 Sakata KI, Kawahata K (1994) Reduction of fundamental polyatomic ions in inductively coupled plasma mass spectrometry. Spectrochim Acta Atom Spectrosc PartB 49 1027-1038 Siehert, C, Nagler, TF, Kramers JD (2001) Determination of molybdenum isotope fractionation by doublespike multicollector inductively coupled plasma mass spectrometry. Geochem Geophys Geosyst 2 2000GC000124... [Pg.149]

Aveston J, Anacker EW, Johnson JS (1964) Hydrolysis of molybdenum (VI). Ultracentrifugation, acidity measurements, and Raman spectra of polymolybdates. Inorg Chem 3 735-746 Baes Jr. CF, Mesmer RE (1986) The Hydrolysis of Cations. Krieger Publishing Company, Melbourne, EL Barling J, Anbar AD (2004) Molybdenum isotope fractionation during adsorption by manganese oxides. Earth Planet Sci Lett, in press... [Pg.451]

Matthews A, Zhu X-K, O Nions K (2001) Kinetic iron stable isotope fractionation between iron (—II) and (—III) complexes in solution. Earth Planet Sci Lett 192 81-92 McManus J, Nagler TE, Siebert C, Wheat CG, Hammond DE (2002) Oceanic molybdenum isotope fractionation Diagenesis and hydrothermal ridge-flank alteration. Geochem Geophys Geosys 3 2002GC000356... [Pg.453]

Siebert C, Nagler TF, von Blanckenburg F, Kramers JD (2003) Molybdenum isotope records as a potential new proxy for paleoceanography. Earth Planet Sci Lett 211 159-171 Stiefel El (1997) Chemical keys to molybdenum enzymes. J Chem Soc Dalton Trans 3915-3923 Stumm W, Morgan JJ (1996) Aquatic Chemistry. New York John Wiley and Sons... [Pg.453]

Yin QZ, Jacobsen SB, Yamashita K (2002) Diverse supernova sources of pre-solar material inferred from molybdenum isotopes in meteorites. Nature 415 881-883 Young ED, Galy A, Nagahara H (2001) Kinetic and equilibrium mass-dependent isotope fractionation laws in nature and their geochemical and cosmochemical significance. Geochim Cosmochim Acta 66 1095-1104... [Pg.454]

Poreda R, Schilling JG, Craig H (1986) Helium and hydrogen isotopes in ocean-ridge basalts north and south of Iceland. Earth Planet Sci Lett 78 1-17 Poulson RL, Siebert C, McManus J, Berelson WM (2006) Authigenic molybdenum isotope signatures in marine sediments. Geology 34 617-620... [Pg.264]

Siebert C, McManus J, Bice A, Poulson R, Berelson WM (2006b) Molybdenum isotope signatures in continental margin sediments. Earth Planet Sci Lett 241 723-733 Sime NG, De la Rocha C, Galy A (2005) Negligible temperature dependence of calcium isotope fractionation in 12 species of planktonic foraminifera. Earth Planet Sci Lett 232 51-66 Simon K (2001) Does 5D from fluid inclusions in quartz reflect the original hydrothermal fluid Chem Geol 177 483 95... [Pg.271]

Molybdenum hexafluoride is used for separation of molybdenum isotopes. [Pg.590]

Nicolussi, G. K., Pellin, M. J., Lewis, R. S. et al. (1998) Molybdenum isotopic compositions of individual presolar silicon carbide grains from the Murchison meteorite. Geochimica et Cosmochimica Acta, 62, 1093-1104. [Pg.155]

Molybdenum isotope ratio measurements by MC-ICP-MS (Plasma 54) have been carried out using Zr or Ru elemental spikes to study the mass discrimination during the whole analytical procedure including sample preparation.146 A laboratory fractionation of Mo isotopes of about 0.15 % is observed during ion exchange by offline Mo separation. Using this analytical technique, possible natural isotope variation of Mo can be determined with a precision of 0.02 %. [Pg.238]

Figure 10 Molybdenum isotopic patterns measured by RIMS in a type X and a mainstream SiC grain (source Pellin et al, 1999). Figure 10 Molybdenum isotopic patterns measured by RIMS in a type X and a mainstream SiC grain (source Pellin et al, 1999).
R. N. (1999) Molybdenum isotopic composition of single silicon carbide grains from supernovae. In Lunar Planet Sci. XXX, 1969. The Lunar and Planetary Institute, Houston (CD-ROM). [Pg.41]

Dauphas N., Marty B., and Reisberg L. (2002) Inference on terrestrial genesis from molybdenum isotope systematics. Geophys. Res. Lett. 29, 1084 doi 10.1029/2001GL014237. [Pg.545]

Arnold G. E., Anbar A. D., and Barling J. (2002) Oxygenation of Proterozoic oceans insight from molybdenum isotopes (abstr.). Geochim. Cosmochim. Acta 66 (15A), A30 (abstracts of the 12th V. M. Goldschmidt Conference, Davos, Switzerland, August 18-23, 2002). [Pg.3462]

See other pages where Molybdenum isotope is mentioned: [Pg.453]    [Pg.230]    [Pg.231]    [Pg.259]    [Pg.271]    [Pg.130]    [Pg.135]    [Pg.15]    [Pg.1352]    [Pg.658]    [Pg.944]    [Pg.392]    [Pg.197]    [Pg.14]    [Pg.31]    [Pg.31]    [Pg.31]    [Pg.34]    [Pg.34]    [Pg.37]   
See also in sourсe #XX -- [ Pg.89 ]

See also in sourсe #XX -- [ Pg.213 ]



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