The IAEA Marine Environment Laboratory (IAEA-MEL) in Monaco has conducted intercomparison exercises on radionuclides in marine samples for many years as part of its contribution to the IAEA's program of Analytical Quality Control Services (AQCS). An important part of the AQCS program has been a production of Reference Materials (RMs) and their provision to radioanalytical laboratories. The RMs have been developed for different marine matrices (sediment, water, biota), with accuracy and precision required for the present state of the art of radiometrics and mass spectrometry methods. The RMs have been produced as the final products of world-wide intercomparison exercises organized during last 30 years. A total of 44 intercomparison exercises were undertaken and 39 RMs were produced for radionuclides in the marine environment. All required matrices (seawater, biota, sediment) have been covered with radionuclide concentrations ranging from typical environmental levels to elevated levels affected by discharges from nuclear reprocessing plants. The long-term availability of RMs (over 10 years) requires the use of very specific techniques to collect and pretreat large quantities of material (e.g., in excess of 100 kg) in order to ensure sample stability and homogenization of any analytes of interest. The production of a RM is therefore a …

We have been developing a semiconductor Compton telescope to explore the universe in the energy band from several tens of keV to a few MeV. We use a Si strip and CdTe pixel detector for the Compton telescope to cover an energy range from 60 keV. For energies above several hundred keV, the higher efficiency of CdTe semiconductor in comparison with Si is expected to play an important role as an absorber and a scatterer. In order to demonstrate the spectral and imaging capability of a CdTe-based Compton Telescope, we have developed a Compton telescope consisting of a stack of CdTe pixel detectors as a small scale prototype. With this prototype, we succeeded in reconstructing images and spectra by solving the Compton equation from 122 keV to 662 keV. The energy resolution (FWHM) of reconstructed spectra is 7.3 keV at 511 keV and 3.1 keV at 122 keV, respectively. The angular resolution obtained at 511 keV is measured to be 12.2{sup o}(FWHM).

An explosive bonding procedure for joining 9.5 mm thick niobium plate to 203 mm thick 6061-T651 Al plate has been developed in order to maximize the bond tensile and impact strengths and the amount of bonded material across the surface of the plate. This procedure improves upon previous efforts, in which the 9.5 mm thick niobium plate is bonded directly to 6061-T4 Al plate. In this improved procedure, thin Nb and Al interlayers are explosively clad between the thicker niobium and aluminum plates. Bonds produced using these optimized parameters display a tensile strength of approximately 255 MPa and an impact strength per unit area of approximately 0.148 J/mm{sup 2}. Specialized mechanical testing geometries and procedures are required to measure these bond properties because of the unique bond geometry. In order to ensure that differences in the thermal expansion coefficients of aluminum and niobium do not adversely affect the bond strength, the effects of thermal cycling at temperatures between -22 C and 45 C on the mechanical properties of these bonds have also been investigated by testing samples in both the as-received and thermal cycled conditions. Based on the results obtained from this series of mechanical tests, thermal cycling is shown …

Hydrocarbon synthesis from photocatalytic reactions of CO{sub 2} and H{sub 2}O over various catalysts has been studied by UV-visible light. The quantum efficiencies suggest that Pd/TiO{sub 2} sol gel exhibits the highest activity for hydrocarbon synthesis from photocatalytic reactions. The in situ IR was able to monitor the adsorbed hydrocarbon species. The UV-visible, IR spectroscopy and XRD techniques were used to characterize the catalysts to obtain the information of properties of the process and catalyst before/after reaction. The UV-visible spectroscopy provides the information about the surface band gap energy of each catalyst. In situ UV-visible studies reveals that TiO{sub 2}-supported catalysts require the higher energy (i.e. shorter wavelength) to pass through the water-thin film deposited on the surface to activate the photocatalytic reaction. XRD data show there is changes in the crystal structure of TiO{sub 2} sol gel from photon energy during photo reaction. Studies on photocatalytic oxidation of methylene blue show that the photocatalytic oxidation rate is significantly higher than the photocatalytic reduction rate on TiO{sub 2} based catalysts. The information from this study can lead to a better understanding of the nature of the catalysts and photoreaction processes, which might provide the information to develop better catalysts and …

A scheme for the solution of the time dependent Maxwell's equations on composite overlapping grids is described. The method uses high-order accurate approximations in space and time for Maxwell's equations written as a second-order vector wave equation. High-order accurate symmetric difference approximations to the generalized Laplace operator are constructed for curvilinear component grids. The modified equation approach is used to develop high-order accurate approximations that only use three time levels and have the same time-stepping restriction as the second-order scheme. Discrete boundary conditions for perfect electrical conductors and for material interfaces are developed and analyzed. The implementation is optimized for component grids that are Cartesian, resulting in a fast and efficient method. The solver runs on parallel machines with each component grid distributed across one or more processors. Numerical results in two- and three-dimensions are presented for the fourth-order accurate version of the method. These results demonstrate the accuracy and efficiency of the approach.

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Funeral program for Mrs. Annie W. Collins, born July 30, 1916 and died September 17, 2005. The funeral was held September 23, 2005 at West End Baptist Church, officiated by Doctor A. Bernard Devers, I. The funeral arrangements were made through Sutton-Sutton Mortuary , Inc.

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This report examines the provisions in the Homeland Security Act of 2002.

This report considers the future of the U.S. tanker fleet for aerial refueling.

This report discuses the responsibilities of the office and process for appointment of the Chief Justice of the United States.

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The Social Services Block Grant (SSBG) is a flexible source of funds that states may use to support a wide variety of social services activities. States have broad discretion over the use of these funds. This short report provides background information on the SSBG and tracks relevant legislation and appropriations measures.

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The authors present measurements of branching ratios and CP-violating asymmetries for neutral B decays into quasi two-body final states dominated by the modes {rho}{sup {+-}}{pi}{sup {-+}} and {rho}{sup {+-}}K{sup {-+}}. The data set used for these measurements was recorded during the 1999-2002 period, and corresponds to a total integrated luminosity of 81.9 fb{sup -1} taken on the {Upsilon}(4S) peak, and 9.5 fb{sup -1} taken 40 MeV off-peak. From a time-dependent maximum likelihood fit they find for the branching fractions {Beta}({rho}{sup 2}{pi}{sup {-+}}) = (22.6 {+-} 1.8(stat) {+-} 2.2(syst)) x 10{sup -6}, {Beta}({rho}{sup {+-}}K{sup {-+}}) = (7.3{sub -1.2}{sup +1.3}(stat) {+-} 1.3(syst)) x 10{sup -6}. For the CP violation parameters, they measure: {Alpha}{sub CP}{sup pK} = 0.28 {+-} 0.17(stat) {+-} 0.080(syst), {Alpha}{sub CP}{sup pk} = -0.18 {+-} 0.08(stat) {+-} 0.029(syst), C{sub pk} = 0.36 {+-} 0.18(stat) {+-} 0.041(syst), S{sub pt} = 0.19 {+-} 0.24(stat) {+-} 0.031(syst), and for the remaining parameters, required to fully describe the time dependence of the B{sup 0}({bar B}{sup 0} {yields} {rho}{sup {+-}}{pi}{sup {-+}}) decays, they obtain {Delta}C{sub pn} = 0.28{sub -0.19}{sup +0.18}(stat) {+-} 0.043(syst), {Delta}S{sub pk} = 0.15 {+-} 0.25(stat) {+-} 0.025(syst).

This chapter describes procedures for the collection and analysis of samples of various matrices for the purpose of determining the presence of chemical agents in a civilian setting. This appendix is intended to provide the reader with sufficient information to make informed decisions about the sampling and analysis process and to suggest analytical strategies that might be implemented by the scientists performing sampling and analysis. This appendix is not intended to be used as a standard operating procedure to provide detailed instructions as to how trained scientists should handle samples. Chemical agents can be classified by their physical and chemical properties. Table 1 lists the chemical agents considered by this report. In selecting sampling and analysis methods, we have considered procedures proposed by the Organization for Prohibition of Chemical Weapons (OPCW), the U. S. Environmental Protection Agency (EPA), and peer-reviewed scientific literature. EPA analytical methods are good resources describing issues of quality assurance with respect to chain-of-custody, sample handling, and quality control requirements.

The production of hydrogen via the thermochemical splitting of water is being considered as a primary means for utilizing the heat from advanced nuclear reactors to provide fuel for a hydrogen economy. The Hybrid Sulfur (HyS) Process is one of the baseline candidates identified by the U.S. Department of Energy [1] for this purpose. The HyS Process is a two-step hybrid thermochemical cycle that only involves sulfur, oxygen and hydrogen compounds. Recent work has resulted in an improved process design with a calculated overall thermal efficiency (nuclear heat to hydrogen, higher heating value basis) approaching 50%. Economic analyses indicate that a nuclear hydrogen plant employing the HyS Process in conjunction with an advanced gas-cooled nuclear reactor system can produce hydrogen at competitive prices. Experimental work has begun on the sulfur dioxide depolarized electrolyzer, the major developmental component in the cycle. Proof-of-concept tests have established proton-exchange-membrane cells (a state-of-the-art technology) as a viable approach for conducting this reaction. This is expected to lead to more efficient and economical cell designs than were previously available. Considerable development and scale-up issues remain to be resolved, but the development of a viable commercial-scale HyS Process should be feasible in time to meet the commercialization …

A new Timing and Synchronization System component, the Universal Networked Timer (UNT), is under development at the National Spherical Torus Experiment (NSTX). The UNT is a second-generation multifunction timing device that emulates the timing functionality and electrical interfaces originally provided by various CAMAC modules. Using Field Programmable Gate Array (FPGA) technology, each of the UNT's eight channels can be dynamically programmed to emulate a specific CAMAC module type. The timer is compatible with the existing NSTX timing and synchronization system and will also support a (future) clock system with extended performance. To assist system designers and collaborators, software will be written to integrate the UNT with EPICS, MDSplus, and LabVIEW. This paper will describe the timing capabilities, hardware design, programming/software support, and the current status of the Universal Networked Timer at NSTX.

Superconducting Radio Frequency (SRF) accelerating structures present a unique design environment for the high-power radio frequency (RF) antennas that deliver power to the cavity to establish the electromagnetic fields and ultimately accelerate beam. These RF couplers need to reliably transmit high power RF with low reflection and insertion loss, while simultaneously maintaining cavity vacuum, minimizing heat leak into the cryomodule, and not adversely affecting the RF cavity or cryomodule mechanics upon cool down. While a majority of research and development (R&D) on SRF couplers have been focused on electron accelerators, advances made in high-power ion accelerator design for the Spallation Neutron Source (SNS), the Japan Proton Accelerator Research Complex (JPARC), and the Rare Isotope Accelerator (RIA) have necessitated developing high-power RF couplers for these applications as well. This paper examines the present state of RF coupler development and R&D for superconducting ion accelerator applications.

The recent advent of parallel machines with tens of thousands of processors is presenting new challenges for obtaining scalability. A particular challenge for large-scale scientific software is determining the inter-processor communications required by the computation when a global description of the data is unavailable or too costly to store. We present a type of rendezvous algorithm that determines communication partners in a scalable manner by assuming the global distribution of the data. We demonstrate the scaling properties of the algorithm on up to 32,000 processors in the context of determining communication patterns for a matrix-vector multiply in the hypre software library. Our algorithm is very general and is applicable to a variety of situations in parallel computing.

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