Isotopes s. Compounds

Californium s greatest danger is as a biological bone-seeking radioactive element, which can be both a radiation hazard and a useful treatment for bone cancer. If mishandled, all of californium s isotopes and compounds can be a potential radiation poison. 

Burreau S, Broman D, Zebuhr Y. 1999. Biomagnification quantification of PBDEs in fish using stable nitrogen isotopes. Organohalogen Compounds 40 363-366. 

A complete analysis of the IR spectra of thienothiophenes 1 and 2 in the gaseous, liquid, and crystalline states was carried out by Kimel feld et al.196,197 The following isotopically substituted compounds were also studied 2-deuterothieno[2,3-6]thiophene (l-2d), 2-deuterothieno[3,2-h]-thiophene (2-2d), 2,5-dideuterothieno[2,3-ft]thiophene (l. S-dj), and 2,5-dideuterothieno[3,2-i]thiophene (2-2,5-d2). The IR spectra of oriented polycrystalline films of all compounds were measured in polarized light, and Raman spectra of liquid thienothiophenes 1, l-2d, and l-2,5-d2, of crystals of thienothiophenes 2 and 2-2,5-d2 and melts of thienothiophenes 2 and 2-2d were analyzed. The planar structure of point-group C2ll for thienothiophene 1 in the liquid and gaseous states was assumed. Then the thirty vibrations of compounds 1 and l-2,5-d2 can be divided into four symmetry classes A2 (11), I (10), A2 (4), and B2 (5) the vibrations of molecule (l-2d) (C, symmetry) are divided into two classes A (21) and A" (9). 

Ognibene, T. J., and Vogel, J. S. (2004). Highly sensitive 14C and 3H quantification of biochemical samples using accelerator mass spectrometry. In Synthesis and Applications of Isotopically Labelled Compounds (Dean, D. C., Filer, C. N., and McCarthy, K. E., Eds.). Wiley, Hoboken, NJ, pp. 293-295. 

Cerling s primary objective was the identification of the processes controlling the carbon-isotope composition of soil CO2, and a quantitative means of describing the process. In terms of notation, carbon isotopes in compounds are evaluated as the ratio (R) of the rare to common stable isotope of carbon ( C/ C) and are reported in delta notation 8 C(%o) = (RJRstd 1)1,000, where R and R td refer to the carbon-isotope ratios of the sample and the international standard, respectively (Friedman and O Neil, 1977). 

IR-4.5.3.2 Specifically labelled compounds An isotopically labelled compound is called a specifically labelled compound when a unique isotopically substituted compound is added formally to the analogous isotopically unmodified compound. A specifically labelled compound is indicated by enclosing the appropriate nuclide symbol(s) and multiplying subscript (if any) in square brackets. 

M. Zielinski and M. Kanska, Synthesis and Uses of Isotopically Labelled Compounds of Bismuth, Antimony and Arsenic, Chap. 15 in The Chemistry of Organic Arsenic, Antimony and Bismuth Compounds (Ed. S. Patai), Wiley, Chichester, 1994. 

Sulfur is a good candidate, with two of its four stable isotopes ( S and S) satisfying criterion (1), and several gaseous compounds satisfying criterion (2), notably SO2 and HaS. In a gas of solar composition, sulfur fails to satisfy criterion (3), and, in fact, NMD effects reports in meteorites are rare and very small (36). However, in the Earth s hydrogen-free atmosphere, NMD effects in sulfur, apparently due to photolysis of volcanic SO2, are well-established (57). 

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