Interaction of radionuclides with argillite from the Eleana Formation on the Nevada Test Site

Distribution coefficients have been determined for {sup 137}Cs, {sup 85}Sr, {sup 144}Ce, {sup 99}Tc, {sup 152}Eu, {sup 238}Pu, {sup 244}Cm, and {sup 243}Am between argillite from the Eleana Formation on the Nevada Test Site (NTS) and several aqueous phases. Radionuclide concentrations in the range of 1 to 0.001 {mu}Ci/ml were used with contact times of 14, 28, and 56 days. Reaction mechanism, concentration effects, exchange capacity, equilibration times, and particle size effects were addressed in a more comprehensive study of the interaction of argillite with Cs in deionized water. The experimental parameters used in the distribution coefficient measurements were based in part on this work. The aqueous phases included a simulated groundwater with composition based on the analysis of a NTS groundwater, the same simulant and deionized water which were pre-equilibrated with powdered argillite, and a groundwater simulant with approximately the same qualitative composition of the NTS simulant, but with a higher ionic strength. A system to provide continuous pH control by CO{sub 2} addition during equilibration of the argillite-solution mixtures was designed and assembled. Initial experiments were done with Cs and Eu and the effects of pH on their distribution coefficients are discussed

Interaction of radionuclides with geomedia from the Nevada Test Site

Aqueous/solid distribution coefficients have been measured for {sup 137}Cs, {sup 85}Sr, {sup 99}Tc, {sup 152}Eu, {sup 144}Ce, {sup 238}Pu, {sup 243}Am and {sup 244}Cm on powdered argillite and hornfels obtained from the Nevada Test Site. The fluid phases included a groundwater simulant and deionized water preequilibrated with powdered argillite. Distribution coefficients for lanthanides and actinides are generally high and Eleana shale was found to effectively sorb technetium

Interaction of radionuclides with argillite from the Eleana Formation on the Nevada Test Site

Distribution coefficients have been determined for {sup 137}Cs, {sup 85}Sr, {sup 144}Ce, {sup 99}Tc, {sup 152}Eu, {sup 238}Pu, {sup 244}Cm, and {sup 243}Am between argillite from the Eleana Formation on the Nevada Test Site (NTS) and several aqueous phases. Radionuclide concentrations in the range of 1 to 0.001 {mu}Ci/ml were used with contact times of 14, 28, and 56 days. Reaction mechanism, concentration effects, exchange capacity, equilibration times, and particle size effects were addressed in a more comprehensive study of the interaction of argillite with Cs in deionized water. The experimental parameters used in the distribution coefficient measurements were based in part on this work. The aqueous phases included a simulated groundwater with composition based on the analysis of a NTS groundwater, the same simulant and deionized water which were pre-equilibrated with powdered argillite, and a groundwater simulant with approximately the same qualitative composition of the NTS simulant, but with a higher ionic strength. A system to provide continuous pH control by CO{sub 2} addition during equilibration of the argillite-solution mixtures was designed and assembled. Initial experiments were done with Cs and Eu and the effects of pH on their distribution coefficients are discussed

Three-dimensional harmonic oscillator and time evolution in quantum mechanics

The problem of defining time (or phase) operator for three-dimensional harmonic oscillator has been analyzed. A new formula for this operator has been derived. The results have been used to demonstrate a possibility of representing quantum-mechanical time evolution in the framework of an extended Hilbert space structure. Physical interpretation of the extended structure has been discussed shortly, too.Comment: 14 pages; submitted to Phys Rev

A Framework for Verifying Data-Centric Protocols

International audienceData centric languages, such as recursive rule based languages, have been proposed to program distributed applications over networks. They simplify greatly the code, while still admitting efficient distributed execution. We show that they also provide a promising approach to the verification of distributed protocols, thanks to their data centric orientation, which allows us to explicitly handle global structures such as the topology of the network. We consider a framework using an original formalization in the Coq proof assistant of a distributed computation model based on message passing with either synchronous or asynchronous behavior. The declarative rules of the Netlog language for specifying distributed protocols and the virtual machines for evaluating these rules are encoded in Coq as well. We consider as a case study tree protocols, and show how this framework enables us to formally verify them in both the asynchronous and synchronous setting

Multifragmentation of 197-Au by 5.0 - 14.6 GeV/c Proton and pi- Beams

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

Understanding How Inequality in the Distribution of Income Affects Health

Research on the determinants of health has almost exclusively focused on the individual but it seems clear we cannot understand or improve patterns of population health without engaging structural determinants at the societal level. This article traces the development of research on income distribution and health to the most recent epidemiologic studies from the USA that show how income inequality is related to age-adjusted mortality within the 50 States. (r 520.62, p 5 0.0001) even after accounting for absolute levels of income. We discuss potential material, psychological, social and behavioral pathways through which income distribution might be linked to health status. Distributional aspects of the economy are important determinants of health and may well provide one of the most pertinent indicators of overall social well-being.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66686/2/10.1177_135910539700200303.pd

Origins of the Ambient Solar Wind: Implications for Space Weather

The Sun's outer atmosphere is heated to temperatures of millions of degrees, and solar plasma flows out into interplanetary space at supersonic speeds. This paper reviews our current understanding of these interrelated problems: coronal heating and the acceleration of the ambient solar wind. We also discuss where the community stands in its ability to forecast how variations in the solar wind (i.e., fast and slow wind streams) impact the Earth. Although the last few decades have seen significant progress in observations and modeling, we still do not have a complete understanding of the relevant physical processes, nor do we have a quantitatively precise census of which coronal structures contribute to specific types of solar wind. Fast streams are known to be connected to the central regions of large coronal holes. Slow streams, however, appear to come from a wide range of sources, including streamers, pseudostreamers, coronal loops, active regions, and coronal hole boundaries. Complicating our understanding even more is the fact that processes such as turbulence, stream-stream interactions, and Coulomb collisions can make it difficult to unambiguously map a parcel measured at 1 AU back down to its coronal source. We also review recent progress -- in theoretical modeling, observational data analysis, and forecasting techniques that sit at the interface between data and theory -- that gives us hope that the above problems are indeed solvable.Comment: Accepted for publication in Space Science Reviews. Special issue connected with a 2016 ISSI workshop on "The Scientific Foundations of Space Weather." 44 pages, 9 figure

Measurement of the B0-anti-B0-Oscillation Frequency with Inclusive Dilepton Events

The $B^0$-$\bar B^0$ oscillation frequency has been measured with a sample of 23 million \B\bar B pairs collected with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we select events in which both B mesons decay semileptonically and use the charge of the leptons to identify the flavor of each B meson. A simultaneous fit to the decay time difference distributions for opposite- and same-sign dilepton events gives $\Delta m_d = 0.493 \pm 0.012{(stat)}\pm 0.009{(syst)}$ ps$^{-1}$.Comment: 7 pages, 1 figure, submitted to Physical Review Letter