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Assistance After Hurricanes and Other Disasters: FY2004 and FY2005 Supplemental Appropriations

Description: After a series of devastating hurricanes struck Florida and other states in the summer of 2004, the 108th Congress passed two emergency supplemental appropriations statutes that provide a total of $16.475 billion to areas stricken by the hurricanes and other natural disasters. The House and Senate quickly approved legislation (H.R. 5005) the day after President Bush submitted a request on September 6 for $2 billion in FY2004 funding, largely in response to the devastation caused by Hurricanes Charley and Frances in Florida. The other issue that was a matter of public debate focused on a proposed amendment in the House to fully offset the cost of the FY2005 supplemental through a proportional reduction in discretionary funds; the House rejected the amendment.
Date: October 22, 2004
Creator: Bea, Keith & Chite, Ralph M.

FY04&05 LDRD Final Report Fission Fragment Sputtering

Description: Fission fragments born within the first 7 {micro}m of the surface of U metal can eject a thousand or more atoms per fission event. Existing data in the literature show that the sputtering yield ranges from 10 to 10,000 atoms per fission event near the surface, but nothing definitive is known about the energy of the sputtered clusters. Experimental packages were constructed allowing the neutron irradiation of natural uranium foils to investigate the amount of material removed per fission event and the kinetic energy distribution of the sputtered atoms. Samples were irradiated but were never analyzed after irradiation. Similar experiments were attempted in a non-radioactive environment using accelerator driven ions in place of fission induced fragments. These experiments showed that tracks produced parallel to the surface (and not perpendicular to the surface) are the primary source of the resulting particulate ejecta. Modeling studies were conducted in parallel with the experimental work. Because the reactor irradiation experiments were not analyzed, data on the energy of the resulting particulate ejecta was not obtained. However, some data was found in the literature on self sputtering of {sup 252}Cf that was used to estimate the velocity and hence the energy of the ejected particulates. Modeling of the data in the literature showed that the energy of the ejecta was much lower than had been anticipated. A mechanism to understand the nature of the ejecta was pursued. Initially it was proposed that the fission fragment imparts its momenta on the electrons which then impart their momenta on the nuclei. Once the nuclei are in motion, the particulate ejecta would result. This initial model was wrong. The error was in the assumption that the secondary electrons impart their momenta directly on the nuclei. Modeling and theoretical considerations showed that the secondary electrons scatter many times before ...
Date: February 22, 2006
Creator: Ebbinghaus, B; Trelenberg, T; Meier, T; Felter, T; Sturgeon, J; Kuboda, A et al.

FY04 LDRD Final Report:Properties of Actinide Nanostructures

Description: Two papers completely describe the objectives and work performed in this laboratory directed research and development (LDRD) project. The first paper published in Review of Scientific Instruments (UCRL-JC-152913) describes the purpose, construction, and operation of a novel instrument to produce and characterize actinide nanostructures by pulsed laser deposition. The second paper submitted to Physical Review B (UCRL-JRNL-209427) describes our work quantifying the oxidation of pulsed laser deposited depleted uranium nanostructures by following the evolution of the electronic structure.
Date: February 22, 2005
Creator: Hamza, A. V.; Trelenberg, T. W. & Tobin, J. G.