Emf measurements were made across the lithium-rich half of the lithiumaluminum system at temperatures from 390 ~ to 550~ using a cell of the type Li/LiC1-KC1 (or LiF-LiC1-LiBr)/Li-A1. The lithium activity increases from 0.007 to approximately 0.7 over the composition range of 48-56 atomic percent (a/o) lithium (the E-phase region). A compound, Li3A12, rather than Li2A1, as reported in standard compilations, exists at temperatures up to the peritectic decomposition at 520r and forms a two-phase region of high lithium activity (>0.85) with the lithium-rich liquid phase. This compound has an estimated free energy of formation of --58 kJ/mole at 700~ The emf data indicate that the lithium-rich liquidus is about 2 a/o richer in lithium than the composition shown in standard compilations of binary phase diagrams.

Effective dose-equivalent responses have been calculated for external exposure from residual photon emitters in soil. The calculations are based on the assumption that the receptor is located 1 m above the contaminated ground. A Monte Carlo algorithm was developed to perform the photon transport calculation for the soil/air configuration, in which the soil constituents were assumed to be similar to those of the earth's crust. Photon cross-sections for soil were based on the latest cross-sectional information generated by the U.S. National Institute of Standards and Technology. For every incident photon at the receptor, an estimate of the air-absorbed dose was calculated first and then converted into the effective dose equivalent. The effective dose equivalent is based on the concept of weighted organ doses, as recommended by the ICRP. The ICRP's latest conversion coefficients were used to transform point air-absorbed doses into effective dose equivalents. Baseline effective dose responses were obtained for monoenergetic photon sources assumed to be distributed uniformly in soil for energies ranging from 0.01 to 10 MeV, soil thicknesses from 0 to 5 mean-free-path (mfp) lengths, and soil densities from 1 to 2 g cm-3. On the basis of the calculated dose responses, empirical relationships were obtained for correlating the dose responses with the soil depths and densities for each source energy. The derived correlations contain a convenient exponential form that describes the depth-dose relationship for an estimated accuracy within about 15%; soil densities show an inverse relationship with dose responses. Results of the effective dose-equivalent response can be used to calculate effective dose-equivalent responses for gamma-emitting radionuclides that are commonly identified as residual radioactive materials in soil.

Die EMK‐Messungen erfolgen an Ketten des Typs Abei Temperaturen zwischen 390 und 550°C. Die Li‐Aktivität steigt bei Änderung der Legierungszusammensetzung von 48 auf 56 Atom % (β‐Phasenbereich) stufenweise von 0,007 bis 0,7 an.

In 2002, the National Council on Radiation Protection and Measurements (NCRP) issued Report No. 141, Managing Potentially Radioactive Scrap Metal. The report evaluates management policy and related issues regarding scrap metal generated in regulated facilities that have been under radiological control or have radiological concerns. It has been estimated that more than 9 million metric tons of scrap metal of all types that have been associated with the production or use of radioactive materials will be generated during the coming decades at various facilities across the United States. Currently, disposition of such metal has encountered particular obstacles, primarily because of the lack of a consistent disposition policy, systematic regulatory provisions, and, above all, public understanding. Without clarity in the regulatory passage, much of the scrap metal, including metal that has not been contaminated, could be mischaracterized as low-level radioactive waste, resulting in a costly disposition operation. NCRP Report No. 141 identifies this general category of metal as "potentially radioactive scrap metal" (PRSM) and discusses the viable disposition options for facilitating its management. Because much of the PRSM has been found to contain very low residual radioactivity or even none at all, one consideration is to release such metal outside of the radiological control framework. This would require the development and implementation of a set of strict release standards in the United States that would necessarily be risk-based and supported by a comprehensive management scheme. Developing a policy of this kind, however, would entail the resolution of many issues, not the least of which would be public acceptance, including that of the metal industry, of the possible recycling of PRSM in the general commerce.

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