Application of Stable Isotopes

The application of stable isotopes has been introduced in Chapter 6, and the following is devoted to illustrating specific applications. 

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Advanced Seminar volume reflects the greatly expanded awareness of the importance of diet reconstruction for understanding past human health and behavior. It also reflects the growing number of applications of stable isotope and trace element analyses of bones and teeth. 

Farquhar, G.D., Hubick, K.T., Condon, A.G. Richards, R.A. (1988). Carbon isotope fractionation and plant water-use efficiency. In Applications of Stable Isotope Ratios to Ecological Research, ed. P.W. Rundel, J.R. Ehleringer K.A. Nagy, pp.21 0. New York Springer-Verlag. 

Hintelmann H, Evans RD. 1997. Application of stable isotopes in environmental tracer studies — measurement of monomethyhnercury (CKjEg ) by isotope dilution ICP-MS and detection of species transformation. Fresenius J Anal Chem 358 378-385. 

With the application of FIA in the mixture analytical mode for the analysis of environmental samples and after a marginal sample pretreatment by SPE, matrix effects are a high probability. But, as cited previously [27—31], matrix effects were not only observed with FIA but also in LC-MS and MS—MS modes. Advice to overcome these problems by, e.g. an improved sample preparation, dilution of the analyte solution, application of stable isotopic modification of LC conditions [29] or even application of two-dimensional LC separations [27], postcolumn standard addition [29], addition of additives into the mobile phase (e.g. propionic acid, ammonium formate) [34,35] or even matrix compounds [32] were proposed and discussed. 

During the last decade knowledge of the ion chemistry of nitro compounds in the gas phase has increased significantly, partly due to the more widespread use of specialized techniques. Thus various ionization methods, in particular electron impact ionization and chemical ionization, have been used extensively. In addition, structure investigations as well as studies on fragmentation pathways have involved metastable ion dissociations, collision activation and neutralization/reionization studies, supplementary to studies carried out in order to disclose the associated reaction energetics and reaction dynamics. In general, the application of stable isotopes plays a crucial role in the in-depth elucidation of the reaction mechanisms. 

In summary, the application of stable isotopes to groundwater studies is based on the fact that the isotopic composition of water behaves conservatively in low-temperature environments where water-rock contact times are short relative to the kinetics of mineral-water isotope exchange reactions. 

Many of the processes responsible for isotope fractionations in the Earth s atmosphere may also occur in the atmospheres of other planetary systems, such as the atmospheric escape of atoms and molecules to outer space. Likely unique to Earth are isotope fractionations related to biological processes or to interactions with the ocean. One aspect of atmospheric research which has great potential for the application of stable isotope investigations is the study of anthropogenic pollution. 

Another application of stable isotopes in clastic rocks is the analysis of weathering profiles, which can potentially provide insight into the continental climate during... 

Table 8.5 Application of stable isotope ratio measurements.

Hydrogeologists take a variety of approaches in quantifying the rates of groundwater exchange with lakes. These approaches can be physically or chemically based isotopic approaches are one example of the chemical methods. The application of stable isotopes to the study of groundwater-lake systems is the primary focus of this chapter. 

Isotopes of oxygen and hydrogen are useful tracers of water sources because they are constituents of the water molecule itself and because they are conservative in aquifers at near-surface temperatures. Isotopic techniques take advantage of the fact that lakes and their surrounding ground-water systems are usually isotopically distinct. Applications of stable isotopes for the study of lakes were first described by Dincer (10) and were discussed in several subsequent review articles (11-14). Most applications of isotopic techniques to lake systems are designed for the determination of water balances, nutrient-uptake studies, and paleotemperature reconstructions. 

Mutlib, A., Lam, W., Atherton, J., Chen, H., Galatsis, P., and Stolle, W. (2005). Application of stable isotope labeled glutathione and rapid scanning mass spectrometers in detecting and characterizing reactive metabolites. Rapid Commun. Mass Spectrom. 19 3482-3492. 

Much of what is currently known about the Earth s climate comes from the application of stable isotopes collected from ocean drill cores in marine sediments (e.g., Zachos et al. 2001). These isotopic data sets provide detailed records of how the Earth s oceans have responded to changing climate and are extremely valuable in assessing global climate histories down to millennial scales. Similar detailed isotopic records for terrestrial systems are, however, uncommon and frequently continuous terrestrial climate records that span millions to tens of millions of years are not preserved in the terrestrial geologic record. With the advent of paleoaltimetry studies targeted directly at the coupled isotopic effects of changes in climate... 

APPLICATIONS OF STABLE ISOTOPE PALEOALTIMETRY Tracking of orogenic rain shadows... 

In this chapter, we discuss paleoaltimetric application of stable isotopes in fossils. Fossils share some features of other stable isotope proxies, for example in their link to atmospheric circulation patterns and meteoric water compositions. However they differ in other key respects, for example in their link to biology, and in their preservation of seasonal isotope variations, reflecting seasonal climate. These variations complicate some interpretations, but also provide alternative approaches to constrain elevations. 

Haskins, N. J. (1982). The application of stable isotopes in biomedical research. Biomed. Mass Spectrom. 9, 269-277. 

Food authentication, application of stable isotope tracers, characterization of complex metallobiomolecules, and investigation of their role in biological processes are all areas in which ICP-MS can play a more and more critical role. Speciation will continue to be a very dynamic field of investigation and the integration of speciation and metabolism studies with the use of stable isotopes as species-specific tracers is likely to become a research area of vital importance. On... 

Separation and Applications of Stable Isotopes, Avona and Spicer, American Laboratory, April 1987. 

It appears likely that the application of stable isotope techniques to the study of paleonutrition will continue. Carbon isotopes have been shown to be useful to trace the introductions of tropical Ck crops into temperate regions where C3 plants predominate. Other recent studies with carbon isotopes have demonstrated that seafoods are more enriched in than terrestrial foods, and that the proportions of marine vs land-derived foods can be estimated in prehistoric coastal people ( ). Elements other than carbon may demonstrate isotopic distributions that will provide useful dietary information. For example, ratios of... 

This phenomenon forms the basis for the formulations of Urey (1947) and Bigeleisen and Mayer (1947) for the temperature dependence of isotopic exchange between two molecules. With the nearly simultaneous development of the isotope-ratio mass spectrometer by Nier et al. (1947), the potential for application of stable isotopes was created. Other isotopic fractionation processes are observed in kinetics, diffusion, evaporation-condensation, crystallization, and biology (e.g., photosynthesis, respiration, nitrogen fixation, sulfate reduction, and transpiration). The concomitant isotopic fractionations can also be used to provide details of the relevant process. 

Elements in nature come in forms called isotopes that differ only in the number of their neutrons. Most isotopes are stable and can be distinguished from their counterparts simply by their masses. Remarkably, isotopes are associated with a few simple and mass-dependent traits that result in a wide range of useful isotopic signals in natural processes. Coupled with the invention of the isotope ratio mass spectrometer in 1940s (McKinney et al., 1950 Nier, 1947) stable isotope signals provide the basis for application of stable isotopes to environmental sciences. Stable isotopes are denoted by their atomic mass such as and for the two stable isotopes of carbon, and 0, and for the stable isotopes of oxygen. Because the heavy isotope is normally rare (e.g., -1.1% for i c, 0.2% for 0, and 0.04% for O), routine measurements of the absolute isotopic concentrations is difficult and not reliable. Alternatively, the ratio, R, of the rare to the abundant isotopes is measured, such as... 

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