Iodine nuclear properties

There are two iodine Mdssbauer resonances. The 27-72-keV transition of I was first observed in 1962 by Jha, Segnan, and Lang [67]. The 57-60-keV transition of I was reported in 1964 by Barros et al. [68]. Both have been used extensively in chemical investigations. The resonance has the better nuclear properties for MOssbauer work, with the unfortunate exception that the ground state is radioactive with a half-life of 1-7 x 10 y. Because of this, I absorbers must be specially prepared and handled, whereas natural iodine comprises the stable I in 100% abundance. 

Table 17.2 Nuclear properties of major iodine isotopes...

Chemical analysis of trace iodine, in either biological or environmental samples, always encounters problems of interference from impurities and uncertainty in chemical yield of analysis. As discussed previously in Chemistry of Iodine Relevance to Radiochemical Studies and Nuclear Properties of Iodine Isotopes , the chemistry of iodine is very complex and isolation or purification of iodine from the sample is a major obstacle in a traditional chemical analysis. 

Table 46.1 Nuclear properties and production model of iodine isotopes with a half life more than 10min ...

In comprehensive treatments of the chemistry of the halogens the properties of fluorine compounds are sufficiently different to motivate a separate chapter. A similar distinction is also practical in a discussion of manifestations of nuclear properties of the halogens, since all stable isotopes of chlorine, bromine and iodine have... 

The NMR properties of the halogens are given in Table 1. The isotopes of chlorine, bromine and iodine have a spin I > Vi and so possess a quadrupole moment. The technique of nuclear quadrupole resonance (NQR) will not be examined in this chapter. The T9F NMR spectra will be discussed as well as the effects of halogen on proton spectra. 

Mossbauer spectroscopy is a nuclear resonance technique and is therefore restricted to particular isotopes with suitable combinations of properties. The severest limitation is the need for gamma-radioactivity, which limits the method to the heavier elements (Z > 18). Amongst the halogens, measurements are possible only for iodine. 

Other accelerator-produced radionuclides are also used in nuclear medicine (Table 19.2). One of the most important radionuclides in this group is This radioisotope of iodine has more favourable properties than it emits only y radiation and its relatively short half-life is more appropriate for medical application. Its production is described in section 12.1. Suitable accelerators for the generation of protons of relatively high energy, and transport facilities, are needed. 

Some of the properties of phenoselenazines, including polarography, electric resistivity, ESR, NMR, crystal structure, and molecular conformation, nuclear spin coupling constants, the cation radical equilibrium constant and the heat of dimerization, the ESR spectrum and mechanism of photoreduction, and the semiconduction behavior of phenoselenazine-iodine complexes, have been reported. 

One of the major goals of research in nuclear medicine is a drug that can be used to demonstrate the brain blood flow pattern. To do this job, a drug should demonstrate four properties. First, it must carry a radioactive isotope that is a positron emitter (best, a fluorine or an iodine atom, for use with the positron camera) that can be put onto the molecule quickly, synthetically, and which will stay on the molecule, metabolically. Second, as to brain entry, the... 

From these two main groups of the Periodic System of Elements, only the elements bromine, iodine, rubidium and cesium are produced by nuclear fission to an extent worth mentioning. Iodine and cesium are of particular interest during plant normal operation as well as in accident situations, because of their comparatively high fission yields, their enhanced mobility in the fuel at higher temperatures and the radiotoxicity of some of their isotopes. Both elements are often summarized under the term volatile fission products their similar properties justify their treatment in the same context, despite pronounced differences in their basic chemical behavior. 

Paquette, J., Ford, B. L. The radiation-induced formation of iodoalkanes and the radiolysis of iodomethane. Proc. 2. CSNI Workshop on Iodine Chemistry in Reactor Safety, Toronto, Can., 1988 Report AECL-9923 (1989), p. 48-73 Paquette, J., Sunder, S., Torgerson, D. F., Wren, C. J., Wren, D. J. The chemistry of iodine and cesium under reactor accident conditions. Proc. 3. BNES Conf. Water Chemistry in Nuclear Reactor Systems, Bournemouth 1983, Vol. 1, p. 71—79 Parsly, L. F. Chemical and physical properties of methyl iodide and its occurrence under reactor accident conditions. Report ORNL-NSIC-82 (1971)... 

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