Improving the Scientific Basis for Managing DOE's Excess Nuclear Materials and Spent Nuclear Fuel (2003) / Chapter Skim
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7 The Higher Actinides
7 The Higher Actinides
Pages 70-80
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From page 70... ...
. DOE's inventory, however, contains substantial amounts of the higher actinides,4 many of which were produced in special campaigns that involved multiple irradiation and separation steps.
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From page 71... ...
Chapter 7 Es, Em 24 9Cf_25°Cf_254Cf_43 38 ,0 y 13 y 900 y Figure 7. ~ The higher actinides were built-up through multiple neutron captures by target isotopes under intense irradiation in DOE's production reactors.
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From page 72... ...
Many studies have been reported in the chemical literature, and a substantial experimental database exists for Np-237 Mossbauer parameters as a function of oxidation state and chemical species (Greenwood and Gibb, 1 971; Long, 1 9841. There are research opportunities to use this technique for fundamental studies that may lead to more efficient separation processes or potentially new uses for neptunium.
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From page 73... ...
feedstock for producing higher actin ides. PIutonium-244 Plutonium-244 is the product of years of intense neutron irradiation of plutonium in nuclear reactors.3 It is used in very small quantities in isotope dilution mass spectrometry to precisely measure the isotopic composition of plutonium being safeguarded by U.S.
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From page 74... ...
As noted earlier, the large demand for Cf-252 envisioned in the mid-1 970s did not materialize. Recently, in treating muscular sarcomas; skin, head and neck tumors; and gynecological tumors, brachytherapy has shown high cure rates and lower recurrence rates compared to other treatment options such as surgery (Fontanesi et al., 1999; Maruyama, 1984 and Maruyama et al., 1986; Rivard et al., 1999; Taeev et al., 2001~.
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From page 75... ...
. New developments continue to arise, such as radioactively tagged monoclonal antibody treatments for leukemia using bismuth-213 being studied at New York City's Sloan Kettering Cancer Center, at ORNL, and at the National Cancer Institute (DOE, 2001 c;Wu, 1997)
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From page 76... ...
A similar center of excellence concept was offered by a previous National Academies' committee, which recommended that EMSP consider establishing field sites for conducting subsurface contamination research to "attract new researchers to the program, encourage both formal and informal multidisciplinary collaborations among researchers, and facilitate the transfer of research results into application" (NRC, 2000, p.
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From page 77... ...
Costs of the EM cleanup program are largely determined by the belief that DOE's former production sites present major health and safety risks. Chapter 7
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From page 78... ...
In Russia, californium has been used mainly in industrial applications rather than in medicine. Uses have included continuous neutron activation analyses in mining operations to sort and grade various ores, reducing production costs.
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From page 79... ...
Use of th is reactor to produce the more stable curium isotopes may have practical benefits as well as encouraging more international collaboration in research on the h igher actin ides. Because the higher actinides are stored as relatively pure, separated materials rather than in the highly heterogeneous mixtures that are characteristic of wastes they are good candidates for long-term storage or disposal in specifically tailored ceramic forms.
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From page 80... ...
With the latter source also producing XPS spectra, one can obtain combined XPS-AES spectra and take advantage of additional spectral parameters on chemical species that cannot be obtained by either XPS or AES alone. The element of imaging adds the possibility of obtaining morphological data concerning interracial reactions on material surfaces.
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