stable isotope

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isotope

 [i´so-tōp]
a chemical element having the same atomic number as another (i.e., the same number of nuclear protons), but having a different atomic mass (i.e., a different number of nuclear neutrons).
radioactive isotope radioisotope.
stable isotope one that does not transmute into another element with emission of corpuscular or electromagnetic radiations.

sta·ble i·so·tope

a nonradioactive nuclide; an isotope that shows no tendency to undergo radioactive decomposition.

sta·ble i·so·tope

(stā'bĕl ī'sŏ-tōp)
A nonradioactive nuclide; an isotope that shows no tendency to undergo radioactive decomposition.

sta·ble i·so·tope

(stā'bĕl ī'sŏ-tōp)
A nonradioactive nuclide; an isotope that shows no tendency to undergo radioactive decomposition.
References in periodicals archive ?
Large variations in [delta][sup.13][C.sub.CH4] values from the IsoJar[TM] measurements (Figure 1) were attributed to methane-oxidizing bacterial activity using sulfate ions in the deep underground environment or to isotopic fractionation during gas migration through fractures [14].
Liu, "Sulfur isotopic fractionation and mechanism for Thermochemical Sulfate Reduction genetic [H.sub.2]S," Acta Petrologica Sinica, vol.
The abundance of [.sup.13]C in marine organic matter and isotopic fractionation in the global biogeochemical cycle of carbon during the past 800 Ma.
It is possible that the Fe isotopic fractionation between the F1 and F2 fractions in the upper 30 cm and lower 30 cm reflects a soil redox change with the lower (deeper?) soils being enriched in [Fe.sup.2+].
Since the analytes underwent physical adsorption and desorption processes before the carbon isotope analysis, several experiments had to be conducted to detect whether carbon isotopic fractionation has occurred during the SPME extraction processes.
Thus, the reaction required to mobilize copper for sedimentary deposits involves the reduction of copper, which would be expected to induce isotopic fractionation favoring [sup.63]Cu, assuming that copper extraction from the source material was incomplete.
reported that the Fe dissimilatory reduction (DIR) promoted by Geobacter sulfurreducens and Shewanella putrefaciens strains caused Fe isotopic fractionation of approximately 2.2[per thousand], with final Fe(II) species enriched in light isotopes [76], which demonstrated that the Fe isotope composition of Fe[(II).sub.aq] is largely controlled by isotopic exchange with a reactive Fe(III) pool that lies in the outer layers of the ferric oxide substrate.
The stable isotope ratios of individual elements are affected by two main factors, namely isotopic fractionation and radioactive decay.
We considered an isotopic fractionation across trophic levels of 3.4 [per thousand] for [delta][sup.15] and 1.0 [per thousand] for [delta][sup.13]C (Vander-Zanden & Rasmussen, 2001; Post, 2002; Wing et al., 2008).
Among the topics are instrumental isotopic fractionation, measurement strategies, chemical imaging, inductively coupled plasma mass spectroscopy, thermal ionization mass spectrometry, secondary ion mass spectroscopy, and gas source isotope ratio mass spectrometry for analyzing noble gases.
Isotopic fractionation of carbon/nitrogen of Mycenas and plants at field sites can reveal the mushroomA[sup.3]s source of carbon, and co-culturing of biotrophic Mycenas together with plants will provide direct evidence for the nature of their relationship(s).