Radioisotope generators

Unlike radioisotope generators, nuclear reactors utilize the much more intense process of nuclear chain reaction. Since this process is controlled in the reactor, the energy output could be regulated depending on the system s requirements. It actually could produce twice its nominal power, if necessai"y. Nuclear reactors can pro dde greater electrical output than radioisotope generators using the same types of thermal converters. This output is comparable to that of fuel cells and solar arrays, while nuclear reactors are more durable and compact. 

Radioisotope generators provide a desirable alternative to cyclotrons for the production of short lived positron emitters. A fully automated microprocessor controlled generator system for obtaining 76 sec rubidium-82 is described in detail. 

Production of Sr-82. An important consideration in the development of radioisotope generators is the availability, cost, and radionuclidic purity of the long-lived parent. In the case of Sr-82, the 25 day radionuclide is needed in 100-200 mCi amounts in order to provide adequate elution yields of Rb-82 from one loading of Sr-82 every three months. Initially the Sr-82 for the generator was produced at the Lawrence Berkeley Laboratory (LBL) 88-inch cyclotron by the Rb-85 (p,4n) Sr-82 nuclear reaction (12). However, because of the long irradiation time required to produce... 

The valuable tracer ""Tc used in nuclear medicine can be obtained as the pertechnetate ion using a Mo Tc generator (see Radioisotope Generators), which takes advantage of the equilibrium between the parent radionuchde Mo and the daughter radionuclide Tc. The separation between the two radionuclides is done on an alumina coluum by the selective elution of [ "Tc04] with a saline solution. 

Unstable Nuclei and Radioactive Decay 4.16. Radioisotope generators... 

Such systems are called radioisotope generators. Rn is sometimes used for the radiotherapeutic treatment of cancer. This product is isolated by separating it as a gas from the parent substance Ra which is normally in the form of solid or a solution of RaBr2. Rn grows into the radium sample with a half-life of 3.8 d. After a 2-week period, following a separation of radon from radiiun, approximately 90% of the maximum amount of radon has grown back in the radium sample. Consequently, it is useful to separate Rn each 2 weeks from the radium samples since further time provides very little additional radioactivity. The Rn is an a emitter the ther utic value comes from the irradiation of the tissue by the y-rays of the decay daughters Pb and Bi which reach radioactive uilibrium extremely rapidly with the Rn. 

Another commonly used radioisotope generator is Te from which may be milked. In this case is adsorbed as barium tellurite on an alumina column, and the removed by passage of 0.01 M ammonia through the column. The is used both diagnostically and therapeutically for thyroid cancer. 

Schumacher J, Maier-Borst W (1981). A new Ge/ Ga radioisotope generator system for production of 68Ga in dilute HCl. Int. J. Appl. Radiat. Isot. 32 31-36. 

Abstract A short history and treatment of the various aspects of nuclear forensic analysis is followed by a discussion of the most common chemical procedures, including applications of tracers, radioisotopic generators, and sample chronometry. Analytic methodology discussed includes sample preparation, radiation detection, various forms of microscopy, and mass-spectrometric techniques. The chapter concludes with methods for the production and treatment of special nuclear materials and with a description of several actual case studies conducted at Livermore. 

Figure 32.17. Aerogel composite panels for thermal insulation of a Stirling radioisotope generator heat source.

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