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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. …

Using a combination of modeling and experimental work we have developed a new method for purifying water that uses less energy than conventional methods and that can be made selective for removing targeted contaminants. The method uses nanoporous membranes that are permselective for anion or cation transfer. Ion selectivity results from double layer overlap inside the pores such that they dominantly contain ions opposite in charge to the surface charge of the membrane. Membrane charge can be adjusted through functionalization. Experiments confirm membrane permselectivity and overall energy use less than that for conventional electrodialysis. The nanoporous membranes are used in a conventional electrodialysis configuration and can be incorporated in existing electrodialysis systems without modification. The technology merits further development and testing in real systems, and could result in a significant reduction in water treatment costs.