Isotopes chloride

There is no reason to believe that any of these reactions involve formation of an intermediate acylium ion (Bentley et al., 1984) but the extent of C—Cl bond breaking probably increases markedly with increasing electron release from a substituent. Kinetic primary chloride isotope effects show that C—Cl bond breaking increases with increasing electron release in hydrolyses of 4-substituted benzoyl chlorides in aqueous acetone (Fry, 1970)... 

One problem is the availability of reliable reference materials for isotope ratio measurements. Certified isotope standard reference materials are available from NIST (National Institute of Standard Reference Materials, http //www.nist.gov/srd/, formerly NBS - National Bureau of Standards) and IRMM (Institute for Reference Materials and Measurements, http //www.irmm.jrc.de). There are isotope standard reference materials for light elements (H, Li, , C, N, O), Mg (magnesium metal isotopic standard NIST SRM 980), and for moderately heavy elements such as (potassium chloride isotopic standard NIST SRM 985), Cr (chromium metal isotopic standard NIST... 

SRM 979), Ni (nickel metal isotopic standard NIST SRM 986), Rb (rubidium chloride isotopic standard NIST SRM 984) and Sr (strontium carbonate isotopic standard NIST SRM 987). In addition, isotope reference materials are available for heavy elements such as T1 (thallium metal isotopic standard NIST SRM 997), Pb (NIST lead standard reference materials SRM 981-983) or U (uranium oxide NIST isotope standard U 005, U020, U350, U500 or U930) and others. The most important isotope standard reference materials applied in inorganic mass spectrometry are summarized in the table in Appendix V.17... 

Figure 26-31 Separation of natural isotopes of 0.56 mM Cl by capillary electrophoresis with indirect spectrophotometrlc detection at 254 nm. Background electrolyte contains 5 mM CrOJ to provide absorbance at 254 nm and 2 mM borate buffer, pH 9.2. The capillary had a diameter of 75 m, a total length of 47 cm (length to detector = 40 cm), and an applied voltage of 20 kV. The difference in electrophoretic mobility of 36C and 37CI is just 0.12%. Conditions were adjusted so that electroosmotlc flow was nearly equal to and opposite electrophoretic flow. The resulting near-zero net velocity gave the two isotopes maximum time to be separated by their slightly different mobilties. [From C. A Lucy and T. L McDonald, "Separation of Chloride Isotopes by Capillary 35 40 45 Electrophoresis Based on the Isotope Effect on Ion Mobility"Anal.

Banks D. A., Gleeson S. A., and Green R. (2000) Determination of the origin of salinity in granite-related fluids evidence from chloride isotopes in fluid inclusions. J. Geochem. Explor. 69-70, 309-312. 

Eastoe C. J., Long A., and Knauth L. P. (1999) Stable chloride isotopes in the Palo Duro Basin, Texas evidence for preservation of Permian evaporite brines. Geochim. Cosmochim. Acta 63, 1375—1382. 

Separation of isotopes is an extremely challenging analytical problem. Lucy and McDonald [4] demonstrated the extraordinary separation power of CE by obtaining a baseline resolution of two chloride isotopes, and Counter migration was... 

Figure 10.5. Separation of chloride isotopes by CE using counter migration (Courtesy of Youchun Shi ).

C. A. Lucy and T. L. McDonald, Separation of chloride isotopes by capillary electrophoresis based on the isotope effect on ion mobility, Anal. Chem., 67,1074,1995. 

The determination of the crystal structure of FsSeOXeOSeFs has confirmed the expected molecular geometry the monomeric units have the OXeO and SeOXe angles 180 and approximately 125°, respectively, although disordering of the O and F atoms has made it impossible to determine certain parameters with sufficient accuracy. Xenon(ii) chloride, isotopically enriched in Xe, has been... 

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