Silver nuclides

Hodge VF, Folson TR. 1972. Estimate of the world budget of fallout silver nuclides. Nature 237 98-99. 

Therefore, the preliminary investigation described herein examined several aspects of the behavior of the equilibrium distribution coefficients for the sorption of rubidium, cesium, strontium, barium, silver, cadmium, cerium, promethium, europium, and gadolinium from aqueous sodium chloride solutions. These solutions initially contained one and only one of the nuclides of interest. For the nuclides selected, values of Kp were then... 

For the nuclides studied (rubidium, cesium, strontium, bariun silver, cadmium, cerium, promethium, europium, and gadolinium) the distribution coefficients generally vary from about 10 ml/gm at solution-phase concentrations on the order of 10 mg-atom/ml to 10 and greater at concentrations on the order of 10 and less. These results are encouraging with regard to the sediment being able to provide a barrier to migration of nuclides away from a waste form and also appear to be reasonably consistent with related data for similar oceanic sediments and related clay minerals found within the continental United States. 

In series 2 a silver nitrate solution spiked with the radioactive nuclide "°Ag was mixed with a sodium selenite solution. The pH was again adjusted from about 1.2 to 12.5 in the mixtures. After equilibration the phases were separated and the pH determined. The total concentration of dissolved silver was found by scintillation spectrometry. The solubility determinations were performed at total concentrations of selenite at 6.45 X 10 0.10, and 0.20 M. 

The principal barriers against fission product release into the environment are the high quality TRISO fuel, the reactor pressure vessel, and the reactor building. The calculation of the fission product release during normal operation of the reactor (Fig. 3-5) which determines the contamination of the primary circuit and thus the source term in case of a depressurization or a water ingress accident has again identified silver to be the nuclide with the largest release fraction. 

Several techniques to measure air concentrations are outlined by Breslin (1980). Most of the techniques for measuring radon use the fact that both radon-222 and the short-lived daughters are alpha- emitting nuclides. The sample is collected and taken back to the laboratory for "alpha-counting" or an alpha-detector is taken to the field for on-site measurement. There are several ways to measure alpha decay. A scintillation flask is one of the oldest and most commonly used methods. The flask is equipped with valves which are lined with a phosphor (silver-activated zinc sulfide) and emit light flashes when bombarded with alpha particles. Other methods draw the air through a filter (or filters) for a variety of time intervals and then count the number of alpha-decays occurring on the filter. EPA (1986) and NCRP (1988) reports provide more in-depth discussions of these methods. 

Folsom, T. R., R. Grismore, and D. R. Young. 1970. Long-lived y-ray emitting nuclide silver-108m found in Pacific marine organisms and used for dating. Nature (London) 227(5261) 941-943. 

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