Isotope chlorine

AIR. (atmospheric) air, a standard for nitrogen and chlorine isotopes APCL atmospheric-pressure chemical ionization, also called plasmaspray API. atmospheric-pressure ionization... 

SMOC. standard mean ocean chloride (a standard for chlorine isotopes)... 

Dichloronitrotoluenes are indicated by the presence of an odd molecular ion with chlorine isotopes showing two chlorine atoms and losses of 30 and 46 Daltons. Again, when the chlorine atoms are on the benzene ring, the loss of chlorine from the molecular ion does not occur. An M - Cl ion indicates that at least one of the chlorines is on the alkyl group. 

Numata M, N Nakamura, H Koshikawa, Y Terashima (2002) Chlorine isotope fractionation during reductive dechloirination of chlorinated ethenes by anaerobic bacteria. Environ Sci Technol 36 4389-4394. 

Sturchio NC, JL Clausen, IJ Heraty, L Huang, BD Holt, TA Abrajano (1998) Chlorine isotope investigation of natural attenuation of trichloroethene in an aerobic aquifer. Environ Sci Technol 32 3037-3042. 

Lewandowicz A, J Rudzinski, L Tronstad, M Widersten, P Ryberg, O Matsson, P Paneth (2001) Chlorine isotope effects on the haloalkane dehalogenase reaction. J Am Chem Soc 123 4550-4555. 

Figure 19.9 compares the observed and library spectra for dichloro-methane (retention time 3.45 min in the GC-MS run). The prominent chlorine isotope pattern for the two chlorine atoms in this spectrum makes it readily identifiable. The primary fragmentation is loss of a chlorine atom, producing the m/z 49 fragment. While this fragment clearly manifests a chlorine isotope pattern still, it reflects the fact that only one chlorine atom remains. Library search identifies this spectrum as dichloromethane with quality-of-fit measures of greater than 95%. 

The retention time results for 35 chlorinated compounds found in sewage sludge are given in Table 9.9. Not all compounds could be identified. A large number of spectra contained what appeared to be chlorine isotope clusters which are not reported. This could be due to interferences, very low levels, or spurious peaks. Although no structure... 

Although GC-C-IRMS systems that can measure the chlorine isotopic composition of individual chlorinated hydrocarbons are currently unavailable, it is clear that chlorine isotope analysis is also a useful technique to consider for study [614,677,678]. Measurement of chlorine stable isotope ratios in natural samples such as rocks and waters has become routine [626,679,680], but few measurements of chlorine isotopes in chlorinated aliphatic hydrocarbons have been reported [614]. A chlorine isotope effect was found in ferf-butyl chloride [681], demonstrating that 37Cl is more strongly bound to carbon than is 35Cl. Significant differences in the <5i7Cl values of some atmospheric chlorinated... 

Chlorine isotope compositions vary by up to 15%o (Chapter 7 Stewart and Spivack 2004). These large variations in Cl isotope compositions are found in marine environments, including mid-ocean ridge basalts, seafloor and hydrothermal alteration products, and sedimentary pore... 

Schauble EA, Rossman GR, Taylor Jr. HP (2001) Theoretical estimates of equilibrium Fe-isotope fractionations from vibrational spectroscopy. Geochim Cosmochim Acta 65 2487-2497 Schauble EA, Rossman GR, Taylor Jr. HP (2003) Theoretical estimates of equilibrium chlorine-isotope fractionations. Geochim Cosmochim Acta 67 3267-3281 Schauble EA, Rossman GR, Taylor Jr. HP (2004) Theoretical estimates of equilibriimi chromium-isotope fractionations. Chem Geol, in press. 

Skulan JL, Beard BL, Johnson CM (2002) Kinetic and equilibrium Fe isotope fractionation between aqueous Fe(III) and hematite. Geochim Cosmochim Acta 66 2995-3015 Stewart MA, Spivack AJ (2004) The stable-chlorine isotope compositions of natural and anthropogenic materials. Rev Mineral Geochem 55 231-254... 

The Stable-Chlorine Isotope Compositions of Natural and Anthropogenic Materials... 

Variations in chlorine isotopic composition are expressed as a per mil (%o) difference (5 Cl) in a measured Cl/ Cl ratio (R) relative to the measured seawater chloride ratio (Standard Mean Ocean Chloride, SMOC),... 

RESULTS AND IMPLICATIONS OF THE STABLE-CHLORINE ISOTOPIC COMPOSITION OF GEOLOGIC AND ANTHROPOGENIC MATERIALS... 

In order to develop a complete understanding of the distribution of chlorine-isotopes in Earth s exogenic (oceans, crust, and atmosphere) and mantle reservoirs it is necessary to... 

Figure 1. Stable-chlorine isotopic composition of meteorites, igneous and metamorphic rocks and minerals reported as 8 Cl relative to Cl/ Cl in Standard Mean Ocean Chloride (SMOC) represented by die vertical dashed line at 0 %o. Data from Magenheim et al. (1994), Magenheim et al. (1995), Bridges et al. (2001), Eggenkamp and Koster van Groos (1997), Boudreau et al. (1997), Willmore et al. (2002), Musashi et al. (1998), Markl et al. (1997), Eggenkamp and Schuiling(1995). Filled symbols are E-MORB and gray boxes represent preliminary data of E-MORB from Stewart (2000).

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