Isotopic parameter

Other Nuclei. Although most nmr experiments continue to involve H, or both, many other nuclei may also be utilized Several factors, including the value of I for the nucleus, the magnitude of the quadmpolar moment, the natural abundance and magnetogyric ratio of the isotope, or the possibihty of preparing enriched samples, need to be considered. The product of the isotopic parameters can be compared to the corresponding value for providing a measure of relative sensitivity or receptivity. Table 1 summarizes these factors for a number of isotopes. More complete information may... 

Bada, J.L., Peterson, R.O., Schimmelmaim, A. and Hedges, R.E.M. 1990 Moose teeth as monitors of environmental isotopic parameters. Oecologia 82 102-106. 

The injected and produced gases and fluids were sampled and analysed for a broad range of chemical and isotopic parameters (Shevalier et al. 2008). The... 

Table 2. Calcium isotopic compositions of terrestrial volcanic rocks, with other related isotopic parameters.

Flow of groundwater in confined aquifers is determined by the water head gradient and by the degree to which the system is drained. In extreme cases water may be trapped in confined aquifers. The topic of water movement in confined aquifers is best studied by means of chemical and isotopic parameters (section 6.5). 

A groundwater transect through the Episode Valley hydrological, chemical, and isotopic parameters... 

Oceanic region Measured isotopic parameters Suggested main formation pathways References... 

All in all, the complexity of the isotopic data and their interpretation in the Acasta Gneiss Complex illustrate the difficulties inherent in study of planetary evolution using polymeta-morphic gneisses. This is the ultimate cause for the controversies over relaibility of radiogenic isotopic parameters derived from these rocks (e.g., Vervoort et al., 1996 Gmau et al., 1996 Moorbath et al., 1997). 

There are two complementary ways to assess the influence of the origin of a precipitation on its isotopic content. First, the combined measurement of both 5D and 5 0 enables the calculation of a second-order isotopic parameter, the deuterium excess (d=5D —86 0) which (see Section 4.08.4.1) depends on the temperature and relative humidity of the evaporative source (and, to a lesser degree, on the wind speed). In turn, this parameter contains information about conditions prevailing in these source regions and it has been applied, as of early 2000s, only for Antarctic sites (Culfey and Vimeux, 2001 Stenni et al., 2001 Vimeux et al, 2002), to correct the conventional approach for source temperature... 

Figure 1 The <5 N of reactant and product N pools of a single unidirectional reaction as a function of the fraction of the initial reactant supply that is left unconsumed, for two different models of reactant supply and consumption, following the approximate equations given in the text. The Rayleigh model (black lines) applies when a closed pool of reactant N is consumed. The steady-state model (gray lines) applies when reactant N is supplied continuously. The same isotopic parameters, an isotope effect e) of 5%o and a <5 N of 5%o for the initial reactant supply, are used for both the Rayleigh and steady-state models, e is approximately equal to the isotopic difference between reactant N and its product (the instantaneous product in the case of the Rayleigh model).

The research was based on the combination of hydrochemical parameters (major and minor ions and ionic relations) and isotopic parameters (6 Hh2o, 5 Oh2o and 5 8304). 

Corrections lor tbe electronic energy are also given in [85Kn6]. Combined analysis of MODR and optical data in [85Kn6]. [87Mak] gives a combined fit of IR data and the MW data from [85Kno] to the potential coefficients Oj, but the obtained isotope parameters dio and doi contain both the correction for the Bom-Oppenheimer approximation and the field shift. 

Monitoring the contents of stable isotopes by MS in the whole sample or in its individual constituents after GC has isolated them is an approach used to get around the weathering problems. It has been shown that the most common stable isotope parameter used (i.e., the ratio) may... 

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