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200-BP-1 Prototype Hanford Barrier Annual Monitoring Report for Fiscal Years 2005 Through 2007

Description: A prototype Hanford barrier was deployed over the 216-B-57 Crib at the Hanford Site in 1994 to prevent percolation through the underlying waste and to minimize spreading of buried contaminants. This barrier is being monitored to evaluate physical and hydrologic performance at the field scale. This report summarizes data collected during the period FY 2005 through FY 2007. In FY 2007, monitoring of the prototype Hanford barrier focused on barrier stability, vegetative cover, evidence of plant and animal intrusion, and the main components of the water balance, including precipitation, runoff, storage, drainage, and deep percolation. Owing to a hiatus in funding in FY 2005 through 2006, data collected were limited to automated measurements of the water-balance components. For the reporting period (October 2004 through September 2007) precipitation amount and distribution were close to normal. The cumulative amount of water received from October 1994 through September 2007 was 3043.45 mm on the northern half of the barrier, which is the formerly irrigated treatment, and 2370.58 mm on the southern, non-irrigated treatments. Water storage continued to show a cyclic pattern, increasing in the winter and declining in the spring and summer to a lower limit of around 100 mm in response to evapotranspiration. The 600-mm design storage has never been exceeded. For the reporting period, the total drainage from the soil-covered plots ranged from near zero amounts under the soil-covered plots to almost 20 mm under the side slopes. Over the 13-yr monitoring period, side slope drainage accounted for about 20 percent of total precipitation while the soil-covered plots account for only 0.12 mm total. Above-asphalt and below-asphalt moisture measurements show no evidence of deep percolation of water. Topographic surveys show the barrier and protective side slopes to be stable. Plant surveys show a relatively high coverage of native plants still persists ...
Date: February 1, 2008
Creator: Ward, Andy L.; Link, Steven O.; Strickland, Christopher E.; Draper, Kathryn E. & Clayton, Ray E.
Partner: UNT Libraries Government Documents Department

FY 2005 Congressional Earmark: The Environmental Institute Fellowship Program

Description: Congressional Earmark Funding was used to create a Postdoctoral Environmental Fellowship Program, interdisciplinary Environmental Working Groups, and special initiatives to create a dialogue around the environment at the University of Massachusetts Amherst to mobilize faculty to work together to respond to emerging environmental needs and to build institutional capacity to launch programmatic environmental activities across campus over time. Developing these networks of expertise will enable the University to more effectively and swiftly respond to emerging environmental needs and assume a leadership role in varied environmental fields. Over the course of the project 20 proposals were submitted to a variety of funding agencies involving faculty teams from 19 academic departments; 4 projects were awarded totaling $950,000; special events were organized including the Environmental Lecture Series which attracted more than 1,000 attendees over the course of the project; 75 University faculty became involved in one or more Working Groups (original three Working Groups plus Phase 2 Working Groups); an expertise database was developed with approximately 275 faculty involved in environmental research and education as part of a campus-wide network of environmental expertise; 12 University centers and partners participated; and the three Environmental Fellows produced 3 publications as well as a number of presentations and papers in progress.
Date: February 6, 2007
Creator: Tracey, Sharon & Taupier, Richard
Partner: UNT Libraries Government Documents Department

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.
Partner: UNT Libraries Government Documents Department

FY05 LDRD Final Report A Computational Design Tool for Microdevices and Components in Pathogen Detection Systems

Description: We have developed new algorithms to model complex biological flows in integrated biodetection microdevice components. The proposed work is important because the design strategy for the next-generation Autonomous Pathogen Detection System at LLNL is the microfluidic-based Biobriefcase, being developed under the Chemical and Biological Countermeasures Program in the Homeland Security Organization. This miniaturization strategy introduces a new flow regime to systems where biological flow is already complex and not well understood. Also, design and fabrication of MEMS devices is time-consuming and costly due to the current trial-and-error approach. Furthermore, existing devices, in general, are not optimized. There are several MEMS CAD capabilities currently available, but their computational fluid dynamics modeling capabilities are rudimentary at best. Therefore, we proposed a collaboration to develop computational tools at LLNL which will (1) provide critical understanding of the fundamental flow physics involved in bioMEMS devices, (2) shorten the design and fabrication process, and thus reduce costs, (3) optimize current prototypes and (4) provide a prediction capability for the design of new, more advanced microfluidic systems. Computational expertise was provided by Comp-CASC and UC Davis-DAS. The simulation work was supported by key experiments for guidance and validation at UC Berkeley-BioE.
Date: February 7, 2006
Creator: Trebotich, D.
Partner: UNT Libraries Government Documents Department

FY05 LDRD Final Report Chemical Dynamics At Interfaces

Description: At high pressure and temperature, the phase diagram of elemental carbon is poorly known. We present predictions of diamond and BC8 melting lines and their phase boundary in the solid phase, as obtained from first principles calculations. Maxima are found in both melting lines, with a triple point located at {approx} 850 GPa and {approx} 7400 K. Our results show that hot, compressed diamond is a semiconductor which undergoes metalization upon melting. In contrast, in the stability range of BC8, an insulator to metal transition is likely to occur in the solid phase. Close to the diamond/ and BC8/liquid boundaries, molten carbon is a low-coordinated metal retaining some covalent character in its bonding up to extreme pressures. Our results provide constraints on the carbon equation of state, which is of critical importance for devising models of Neptune, Uranus and white dwarf stars, as well as of extra-solar carbon-rich planets.
Date: February 9, 2006
Creator: Schwegler, E; Ogitsu, T; Bonev, S; Correa, A; Militzer, B & Galli, G
Partner: UNT Libraries Government Documents Department

FY05 LDRD Final Report Coupled Turbulenc/Transport Model for Edge-Plasmas

Description: An edge-plasma simulation for tokamak fusion devices is developed that couples 3D turbulence and 2D transport, including detailed sources and sinks, to determine self-consistent steady-state plasma profiles. Relaxed iterative coupling is shown to be effective when edge turbulence is partially suppressed, for example, by shear E x B shear flow as occurs during the favorable H-mode region. Unsuppressed turbulence is found to lead to large, intermittent edge transport events where the coupling procedure can lead to substantial inaccuracies in describing the true time-averaged plasma behavior.
Date: February 9, 2006
Creator: Rognlien, T; Cohen, R; LoDestro, L; Palasek, R; Umansky, M & Xu, X
Partner: UNT Libraries Government Documents Department

FY05 LDRD Final Report Mapping Phonons at High-pressure

Description: In order to shed light on the intriguing, and not yet fully understood fcc-isostructural {gamma} {yields} {alpha} transition in cerium, we have begun an experimental program aimed at the determination of the pressure evolution of the transverse acoustic (TA) and longitudinal acoustic (LA) phonon dispersions up to and above the transition. {gamma}-Ce Crystals of 60-80 mm diameter and 20 mm thickness were prepared from a large ingot, obtained from Ames Lab, using laser cutting, micro-mechanical and chemical polishing techniques. Three samples with a surface normal approximately oriented along the [110] direction were loaded into diamond anvil cells (DAC), using neon as a pressure transmitting medium. The crystalline quality was checked by rocking curve scans and typical values obtained ranged between one and two degrees. Only a slight degradation in the sample quality was observed when the pressure was increased to reach the {alpha}-phase, and data could be therefore recorded in this phase as well. The spectrometer was operated at 17794 eV in Kirkpatrick-Baez focusing geometry, providing an energy resolution of 3 meV and a focal spot size at the sample position of 30 x 60 mm{sup 2} (horizontal x vertical, FWHM). Eight to ten IXS spectra were typically recorded per phonon branch. Figure 1 reports the pressure dependence of the LA[100] branch in the {gamma}-phase for pressures of 1, 4 and 6 kbar, together with previous inelastic neutron scattering (INS) results [1] at ambient pressure. A clear decrease of the phonon energies with increasing pressure is observed for 1 and 4 kbar, whereas the phonon energies increase again at 6 kbar, still well within the stability field of the {gamma}-phase. Figure 2 reports the LA dispersion along all three main symmetry directions at 6 kbar ({gamma}-phase) and 8 kbar ({alpha}-phase), together with the INS results at ambient conditions. Besides the ...
Date: February 10, 2006
Creator: Farber, D. L.; Antonangelli, D.; Beraud, A.; Krisch, M. & Aracne, C.
Partner: UNT Libraries Government Documents Department

FY05 LDRD Final Report Molecular Engineering of Electrodialysis Membranes 03-ERD-060

Description: 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.
Date: February 22, 2006
Creator: Bourcier, W; O'Brien, K; Sawvel, A; Johnson, M; Bettencourt, K; Letant, S et al.
Partner: UNT Libraries Government Documents Department

FY05 LDRD Final Report Molecular Radiation Biodosimetry LDRD Project Tracking Code: 04-ERD-076

Description: In the event of a nuclear or radiological accident or terrorist event, it is important to identify individuals that can benefit from prompt medical care and to reassure those that do not need it. Achieving these goals will maximize the ability to manage the medical consequences of radiation exposure that unfold over a period of hours, days, weeks, years, depending on dose. Medical interventions that reduce near term morbidity and mortality from high but non-lethal exposures require advanced medical support and must be focused on those in need as soon as possible. There are two traditional approaches to radiation dosimetry, physical and biological. Each as currently practiced has strengths and limitations. Physical dosimetry for radiation exposure is routine for selected sites and for individual nuclear workers in certain industries, medical centers and research institutions. No monitoring of individuals in the general population is currently performed. When physical dosimetry is available at the time of an accident/event or soon thereafter, it can provide valuable information in support of accident/event triage. Lack of data for most individuals is a major limitation, as differences in exposure can be significant due to shielding, atmospherics, etc. A smaller issue in terms of number of people affected is that the same dose may have more or less biological effect on subsets of the population. Biological dosimetry is the estimation of exposure based on physiological or cellular alterations induced in an individual by radiation. The best established and precise biodosimetric methods are measurement of the decline of blood cells over time and measurement of the frequency of chromosome aberrations. In accidents or events affecting small numbers of people, it is practical to allocate the resources and time (days of clinical follow-up or specialists laboratory time) to conduct these studies. However, if large numbers of people have been ...
Date: February 3, 2006
Creator: Jones, I M; A.Coleman, M; Lehmann, J; Manohar, C F; Marchetti, F; Mariella, R et al.
Partner: UNT Libraries Government Documents Department

FY05 LDRD Final Report Sensor Fusion for Regional Monitoring of Nuclear Materials with Ubiquitous Detection

Description: The detection of the unconventional delivery of a nuclear weapon or the illicit transport of fissile materials is one of the most crucial, and difficult, challenges facing us today in national security. A wide array of radiation detectors are now being deployed domestically and internationally to address this problem. This initial deployment will be followed by radiation detection systems, composed of intelligent, networked devices intended to supplement the choke-point perimeter systems with more comprehensive broad-area, or regional coverage. Cataloging and fusing the data from these new detection systems will clearly be one of the most significant challenges in radiation-based security systems. We present here our results from our first 6 months of effort on this project. We anticipate the work will continue as part of the Predictive Knowledge System Strategic Initiative.
Date: February 15, 2006
Creator: Labov, S E & Craig, W W
Partner: UNT Libraries Government Documents Department

FY05 LDRD Final Report Technology Basis for Fluorescence Imaging in the Nuclear Domain (FIND)

Description: Work performed as a part of this ER sets the foundation for applications of high brightness light sources to important homeland security and nonproliferation problems. Extensive modeling has been performed with the aim to understand the performance of a class of interrogation systems that exploit nuclear resonance fluorescence to detect specific isotopes, of particular importance for national security and industry.
Date: February 13, 2006
Creator: Barty, C J
Partner: UNT Libraries Government Documents Department

FY05 LDRD Final ReportNanomaterials for Radiation Detection

Description: We have demonstrated that it is possible to enhance current radiation detection capability by manipulating the materials at the nano level. Fabrication of three-dimensional (3-D) nanomaterial composite for radiation detection has great potential benefits over current semiconductor- and scintillation-based technologies because of the precise control of material-radiation interaction and modulation of signal output. It is also a significant leap beyond current 2-D nanotechnology. Moreover, since we are building the materials using a combination of top-down and bottom-up approaches, this strategy to make radiation detection materials can provide significant improvement to radiation-detection technologies, which are currently based on difficult-to-control bulk crystal growth techniques. We are applying this strategy to tackle two important areas in radiation detection: gamma-rays and neutrons. In gamma-ray detection, our first goal is to employ nanomaterials in the form of quantum-dot-based mixed matrices or nanoporous semiconductors to achieve scintillation output several times over that from NaI(Tl) crystals. In neutron detection, we are constructing a 3-D structure using a doped nanowire ''forest'' supported by a boron matrix and evaluating the detection efficiency of different device geometry with simulation.
Date: February 6, 2006
Creator: Wang, T F; Letant, S E; Nikolic, R J & Chueng, C L
Partner: UNT Libraries Government Documents Department

FY05 LDRD Final ReportTime-Resolved Dynamic Studies using Short Pulse X-Ray Radiation

Description: Established techniques must be extended down to the ps and sub-ps time domain to directly probe product states of materials under extreme conditions. We used short pulse ({le} 1 ps) x-ray radiation to track changes in the physical properties in tandem with measurements of the atomic and electronic structure of materials undergoing fast laser excitation and shock-related phenomena. The sources included those already available at LLNL, including the picosecond X-ray laser as well as the ALS Femtosecond Phenomena beamline and the SSRL based sub-picosecond photon source (SPPS). These allow the temporal resolution to be improved by 2 orders of magnitude over the current state-of-the-art, which is {approx} 100 ps. Thus, we observed the manifestations of dynamical processes with unprecedented time resolution. Time-resolved x-ray photoemission spectroscopy and x-ray scattering were used to study phase changes in materials with sub-picosecond time resolution. These experiments coupled to multiscale modeling allow us to explore the physics of materials in high laser fields and extreme non-equilibrium states of matter. The ability to characterize the physical and electronic structure of materials under extreme conditions together with state-of-the-art models and computational facilities will catapult LLNL's core competencies into the scientific world arena as well as support its missions of national security and stockpile stewardship.
Date: February 10, 2006
Creator: Nelson, A; Dunn, J; van Buuren, T; Budil, K; Sadigh, B; Gilmer, G et al.
Partner: UNT Libraries Government Documents Department

Intelligence Authorization Legislation: Status and Challenges

Description: This report assesses the effects of the absence of intelligence authorization legislation since FY2005. Since FY2005, no annual intelligence authorization bill has been enacted. Although the National Security Act requires intelligence activities to be specifically authorized, this requirement has been satisfied in recent years by one-sentence catch-all provisions in defense appropriations acts authorizing intelligence activities.
Date: February 24, 2009
Creator: Best, Richard A., Jr.
Partner: UNT Libraries Government Documents Department

Multilateral Development Banks: U.S. Contributions FY1998-FY2009

Description: This report shows in tabular form how much the Administration requested and how much Congress appropriated during the past 11 years for U.S. payments to the multilateral development banks (MDBs). It also provides a brief description of the MDBs and the ways they fund their operations.
Date: February 3, 2010
Creator: Sanford, Jonathan E.
Partner: UNT Libraries Government Documents Department

Multilateral Development Banks: U.S. Contributions FY2000-FY2013

Description: This report shows in tabular form how much the Administration requested and how much Congress appropriated for U.S. payments to the multilateral development banks (MDBs) since 2000. It also provides a brief description of the MDBs and the ways they fund their operations. It will be updated periodically as annual appropriation figures are known.
Date: February 1, 2013
Creator: Nelson, Rebecca M.
Partner: UNT Libraries Government Documents Department