Gadolinium nuclides

HPLC-ICP-MS and CE-ICP-MS, are compared with the table values and theoretical results. 155Gd is the most highly abundant nuclide. Compared to the isotope pattern in natural samples more light gadolinium nuclides with a typical isotopic pattern were formed by the irradiation of with high energy protons. 

Silvery, artificial element generated by beta decay from a plutonium isotope (239Pu). Chemically similar to gadolinium. Like Eu and Gd, Am and Cm are difficult to separate. It can be produced in kilogram amounts. The most common isotope is 244Cm with a half-life of 18.1 years. Is used for thermoelectric nuclide batteries in satellites and pacemakers. It is strongly radioactive and hence also suitable for material analysis. 

Table 9.41 Nuclide abundances of gadolinium (%) produced via spallation reactions in an irradiated tantalum target via spallation reactions.

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. 

Calculations indicate the most effecive use of soluble poisons may involve mixtures of several different elements, such as a mixture of boron and gadolinium, since one nuclide is more effective than another in absorbing neutrons from different portions of the neutron spectrum as the fuel concentration, or H/X ratio, is varied. As these are the first data known to be reported on boron-gadolinium mixtures, the data provide the only validation points for calculations of the mixed absorber effects. 

Because of the high radiotoxicity of most of the actinide nuclides, only very limited studies of the biokinetics of plutonium and other important actinides are possible in human volunteers. As our information about the long-term retention of actinides is limited, there is interest in the possible use of stable lanthanide elements as surrogates for the actinides for long-term biokinetic studies in humans. The aim of such studies is to inject appropriate stable isotopes of lanthanides such as cerium, europium, and gadolinium into human volunteers and then to measure the excretion of the lanthanide in urine and faeces by mass spectrometry, charged-particle activation analysis or similar methods. Also, limited human studies can also be carried out using small doses of appropriate lanthanide radionuclides (Bailey 1989). 

Gadolinium-146 undergoes electron capture. Identify the product, and use Figure 23.2 to find the modes of decay and the other two nuclides in the series below ... 

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