Results 241 to 250 of about 71,609 (291)

Isotope shift in Cr I

Physics Letters A, 1967
Abstract In transitions of the type 3 d 5 4 s − 3 d 5 4 p in a difference in field shift of 4.4 × 10 -3 cm -1 was found for the isotope pairs 54, 52 and 52, 50. This result signifies a jump of field shift at the closed neutron shell N = 28.
K. Heilig, D. Wendlandt
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Structure of the neutron-rich Cr isotopes

Journal of Physics G: Nuclear and Particle Physics, 2005
The low-lying levels in 59,60Cr have been populated with 13,14C(48Ca, 2p) reactions using a beam energy of 130 MeV. Prompt electromagnetic radiation was detected using the Gammasphere array, in coincidence with recoiling ions measured with the Fragment Mass Analyzer. The residues were selected and identified on the basis of charge-to-mass ratio, energy-
Freeman, S. J., Janssens, R. V F, Deacon, A. N., Xu, F., Calderin, I. J., Carpenter, M. P., Chowdhury, P., Fischer, S. M., Hammond, N. J., Honma, M., Lauritsen, T., Lister, C. J., Khoo, T. L., Mukherjee, G., Seweryniak, D., Smith, J. F., Tabor, S. L., Varley, B. J., Zhu, S.   +18 more
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Oxygen isotope compositions of chondrules in CR chondrites

Geochimica et Cosmochimica Acta, 2006
Abstract We report in situ ion microprobe analyses of oxygen isotopic compositions of olivine, low-Ca pyroxene, high-Ca pyroxene, anorthitic plagioclase, glassy mesostasis, and spinel in five aluminum-rich chondrules and nine ferromagnesian chondrules from the CR carbonaceous chondrites EET92042, GRA95229, and MAC87320.
Alexander N. Krot, Guy Libourel, Marc Chaussidon   +2 more
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Cr isotope systematics in the Connecticut River estuary

Chemical Geology, 2019
Abstract Stable chromium (Cr) isotopes (expressed in δ53Cr as the deviation of 53Cr/52Cr in samples from the international standard NIST SRM 979) are an emerging paleoredox proxy that has been used to track Earth's redox evolution over a range of timescales.
Zeyang Sun, Xiangli Wang, Noah Planavsky
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Two-stage chromium isotope fractionation during microbial Cr(VI) reduction

Water Research, 2019
Chromium isotope fractionation analysis is a promising approach for the assessment of microbial Cr(VI) reduction in groundwater. Understanding the mechanisms and other parameters that control Cr isotope fractionation factors (between the product Cr(III) and reactant Cr (VI)) in microbial Cr(VI) reduction is critical to this application.
Guojun, Chen, Juncheng, Han, Yang, Mu, Huimin, Yu, Liping, Qin   +4 more
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Cr-isotopes: analytical methods, spike calculations and application to Environmental Sciences

Acta Vulcanologica : journal of the national volcanic group of Italy, 2007
Chromium is found in soils and waters from natural sources and anthropogenic activities. It occurs in the environment in two main valence states; hexavalent Cr(VI) and trivalent Cr(III). Within the range of pH and redox potential commonly found in soils and water, there are two trivalent forms of Cr (the Cr3+ cation and the CrO2- anion) and two ...
PETRINI, RICCARDO, Cavazzini G., Slejko F. F.   +2 more
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Cr stable isotope fractionation by evaporation from silicate melts

Chemical Geology, 2022
ISSN:1872 ...
Klemme, Stephan, Genske, Felix, Sossi, Paolo A., Berndt, Jasper, Renggli, Christian J., Stracke, Andreas   +5 more
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Geochemistry and Cr stable isotopes of Cr-contaminated groundwater in León valley, Guanajuato, México

Applied Geochemistry, 2012
Abstract Leon valley, located in the Mexican state of Guanajuato, has a long history (35+ a) of Cr contamination of groundwater and surface water. Here data are presented for Cr, major ion and trace element concentrations and Cr stable isotope measurements of groundwater in a heavily contaminated aquifer in Buenavista, where Cr ore processing residue
Alejandro Villalobos-Aragón, Andre S. Ellis, María A. Armienta, Ofelia Morton-Bermea, Thomas M. Johnson   +4 more
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Isotopic fractionation and reaction kinetics between Cr(III) and Cr(VI) in aqueous media

Geochimica et Cosmochimica Acta, 2010
Abstract The redox-sensitive stable isotope geochemistry of chromium bears the potential to monitor the attenuation of chromate pollution and to investigate changes in environmental conditions in the present and the past. The use of stable Cr isotope data as a geo-environmental tracer, however, necessitates an understanding of the reaction kinetics ...
Zink, Sonja, Schoenberg, Ronny, Staubwasser, Michael   +2 more
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Application of double-spike isotope dilution for the accurate determination of Cr(III), Cr(VI) and total Cr in yeast

Analytical and Bioanalytical Chemistry, 2006
A method is presented for the simultaneous determination of Cr(III) and Cr(VI) in yeast using species-specific double-spike isotope dilution (SSDSID) with anion-exchange liquid chromatography (LC) separation and sector field inductively coupled plasma mass spectrometric (SF-ICP-MS) detection. Total Cr is quantitated using ID SF-ICP-MS.
Yang, L., Ciceri, E., Mester, Z., Sturgeon, R.   +3 more
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