The effects of isotopic separation on closed nuclear fuel cycles

This paper investigates the potential benefits to the fuel cycle outcomes of removing a single isotope during separation processes. Two strategies for managing the removed isotope are considered. The first strategy looks at removal of a short to intermediate lived isotope from a mass stream to be recycled and subsequently recycling its decay daughter in a transmuting reactor. The second investigates the effect of removing a long lived fission product from high level waste and recycling it into the transmuting reactor. This analysis shows that the removal of Cm-244 using the first strategy provides a marked benefit to several fuel cycle metrics. The second strategy benefits the long term radioactivity measured from the high level waste from isotopes including Zr-93 and Cs-137.Mechanical Engineerin

Wage Concessions and Long-Term Union Wage Flexibility

macroeconomics, wage concessions, union

Advanced underwater lift device

Flexible underwater lift devices ('lift bags') are used in underwater operations to provide buoyancy to submerged objects. Commercially available designs are heavy, bulky, and awkward to handle, and thus are limited in size and useful lifting capacity. An underwater lift device having less than 20 percent of the bulk and less than 10 percent of the weight of commercially available models was developed. The design features a dual membrane envelope, a nearly homogeneous envelope membrane stress distribution, and a minimum surface-to-volume ratio. A proof-of-concept model of 50 kg capacity was built and tested. Originally designed to provide buoyancy to mock-ups submerged in NASA's weightlessness simulators, the device may have application to water-landed spacecraft which must deploy flotation upon impact, and where launch weight and volume penalties are significant. The device may also be useful for the automated recovery of ocean floor probes or in marine salvage applications

Advanced collapsible tank for liquid containment

Tanks for bulk liquid containment will be required to support advanced planetary exploration programs. Potential applications include storage of potable, process, and waste water, and fuels and process chemicals. The launch mass and volume penalties inherent in rigid tanks suggest that collapsible tanks may be more efficient. Collapsible tanks are made of lightweight flexible material and can be folded compactly for storage and transport. Although collapsible tanks for terrestrial use are widely available, a new design was developed that has significantly less mass and bulk than existing models. Modelled after the shape of a sessible drop, this design features a dual membrane with a nearly uniform stress distribution and a low surface-to-volume ratio. It can be adapted to store a variety of liquids in nearly any environment with constant acceleration field. Three models of 10L, 50L, and 378L capacity have been constructed and tested. The 378L (100 gallon) model weighed less than 10 percent of a commercially available collapsible tank of equivalent capacity, and required less than 20 percent of the storage space when folded for transport

Labor Policy and the Great Recession

Labor and Employment Law Under the Obama Administration: A Time for Hope and Change? Symposium held November 12-13, 2010, Indiana University Maurer School of Law, Bloomington, Indiana