Radionuclides plutonium

Millions of radioactive sources exist around the world, usually distributed not only at nuclear power plants, but also medical radiotherapy facihties and industrial irradiators. Unfortunately, the radioactive materials housed in these places are often not under adequate control and are therefore susceptible to theft by terrorists.34 The appalling events of September 11, 2001, spawned a major international initiative to strengthen security for such materials and facihties worldwide. Highly toxic radionuchdes (plutonium radionuclides, 210Po or 137Cs) at trace level are increasingly being used as modern weapons to kill undesirable persons. 

Activity Determination of Polonium, Radiolead, Uranium, and Plutonium Radionuclides... 

FIGURE 11.6 Alpha spectra of plutonium radionuclides (238Pu, 239 24opLI, and 242Pu). 

If the background count is very low, and during the analysis time A0 = At (for uranium and plutonium radionuclides), then... 

The radioactivities of the plutonium radionuclides in the high-level wastes from fuel reprocessing are shown as a function of storage time in Fig. 8.8 [PI], Because the initial plutonium quantities are due only to the small fraction, e.g., 0.5 percent, of the plutonium that is lost to these wastes in reprocessing, larger quantities appear after a few years due to the decay of americium and curium. The Pu increases with time because of the decay of " Am and Cm, Pu increases from the decay of Am and Cm, and Pu increases due to the decay of Cm. Therefore, even though the total actinide activity in these wastes is dominated by plutonium after the americium has decayed, the plutonium in the wastes at this time is due mainly to the earlier decay of americium and curium and not to the small fraction of plutonium lost to the wastes in fuel reprocessing. 

Noshkin V, Wong K, Marsh K, et al. 1976. Plutonium radionuclides in the groundwaters at... 

Reactor plutonium recovered from low enriched uranium spent fuel (less than 5% U-235) constitutes a typical example of a mixture of radionuclides with known identity and quantity for each constituent. Calculations according to para. 404 of the Regulations result in activity limits independent of the abundance of the plutonium radionuclides and the bumup within the range 10 000-40 000 MW d/t. The following values for reactor plutonium can be used within the above range of bumup, the Am-241 buildup taken into account, up to five years after recovery ... 

An interesting aspect of the characterization of plutonium as Pu(V) in the Irish Sea, Lake Michigan, and Pond 3513 is that the origins of the radionuclides are different in each system, i.e., fuel reprocessing waste, fallout, and laboratory effluents, respectively. 

Workers at plutonium reprocessing facilities, nuclear reactors, transuranium and low level waste storage facilities, or those engaged in the production or processing of243Am or241 Am may be occupationally exposed to americium. In addition, workers at sites where nuclear testing was conducted may also be exposed to americium. Workers in nuclear power stations may be exposed to airborne radionuclides. The... 

ICP-MS (inductively coupled plasma mass spectrometry) is frequently used for determining ultratrace amounts of technetium [9]. In spite of the high cost of the equipment, this detection method is far superior to other radiometric methods as regards sensitivity. When a double focussing high-resolution system is used (HR-ICP-MS) and an ultrasonic nebulizer is introduced [10], the detection limit is in the order 0.002 mBq. The ICP-MS method has been successfully applied to the determination of environmental "Tc as well as to other long-lived radionuclides of neptunium and plutonium in the environment. 

Radiometric detection technology, 21 271 Radiometric ore sorting, 16 626 Radiometric techniques, for plutonium analysis, 19 699-700 Radiometry, 23 142-143 Radionuclide removal... 

Table 2.1 lists specific radionuclides that may be present in nuclear fuel rods or industrial sources used to construct a dirty bomb. It also lists the radiological half-lives of each radionuclide, whether they are present in fresh or spent fuel rods, and their potential industrial applications. Note that the actual suites of isotopes for given fuel rods will vary depending on the origin and composition of the original fuel mixture. The uranium and plutonium isotopes found in fuel rods may also be found... 

Disposal of spent nuclear fuel and other radioactive wastes in the subsurface and assessment of the hazards associated with the potential release of these contaminants into the environment require knowledge of radionuclide geochemistry. Plutonium (Pu), for example, exhibits complex environmental chemistry understanding the mechanism of Pu oxidation and subsequent reduction, particularly by Mn-bearing minerals, is of major importance for predicting the fate of Pu in the subsurface. 

Carpenter R, Beasley TM, Zahnie D, et al. 1987. Cycling of fallout (plutonium, americium-241, cesium-137) and natural (uranium, thorium, lead-210) radionuclides in Washington continental slope sediments. Geochim Cosmochim Acta 51 1897-1921. 

Santschi PH, Li YH, Adler DM, et al. 1983. The relative mobility of natural (thorium, lead and polonium) and fallout (plutonium, americium, cesium) radionuclides in the coastal marine environment Results from model ecosystems (MERL) and Narragansett Bay. Geochim Cosmochim Acta 47 201-210. 

Singh, NP, Ibrahim SA, Cohen N, et al. 1979. Simultaneous determination of alpha-emitting radionuclides of thorium plutonium in human tissues including bone. Analytical Chem 51 1978-1981. 

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