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Phase II Hydrologic Data for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 98: Frenchman Flat, Nye County, Nevada, Rev. No.: 0

Description: This report documents pertinent hydrologic data and data analyses as part of the Phase II Corrective Action Investigation (CAI) for Frenchman Flat (FF) Corrective Action Unit (CAU): CAU 98. The purpose of this data compilation and related analyses is to provide the primary reference to support the development of the Phase II FF CAU groundwater flow model.
Date: December 1, 2004
Creator: McCord, John
Partner: UNT Libraries Government Documents Department

Molecular Characterization of the Role of a Calcium Channel in Plant Development

Description: A stimulus-induced change in cellular Ca2+ levels is a critical component of energy transduction in plant and animal development. Demonstrating Ca2+'s involvement in any developmental process requires identification of mechanisms that regulate these Ca2+ changes. In plants, biochemical studies have implicated the activity of Ca2+ channels in increases in cellular Ca2+ levels; however, molecular evidence for these transporters is lacking. Our studies used the mosses Physcomitrella patens and Funaria hygrometrica to establish a role for Ca2+ in hormone-induced morphogenesis and to use this developmental process to identify transporters responsible for increasing cytosolic Ca2+ levels. Using 1,4-dihydropyridines (DHPs), molecules that block Ca2+ movement through voltage-dependent channels in animal cells, we have shown that Ca2+ is important early in the transition from filamentous to meristematic-like growth that occurs in response to the plant hormone cytokinin. In addition to inhibiting moss growth (see below), these Ca2+ channel blockers prevent Ca2+ transport into moss cells (Schumaker and Gizinski, 1993) and bind specifically to two proteins in the moss plasma membrane (Schumaker and Gizinski, 1994; 1996; Dietrich et al., unpublished results). We used tandem mass spectrometry of the partially purified DHP-binding proteins with the goal of identifying the putative Ca2+ channel and providing sequence information for studies to understand channel expression, regulation, structure, and function during development. In addition, we used insertional mutagenesis to identify additional components of the pathway underlying hormone-induced morphogenesis.
Date: December 21, 2004
Creator: Schumaker, Karen S.
Partner: UNT Libraries Government Documents Department

Gyrokinetic Studies of Turbulence in Steep Gradient Region: Role of Turbulence Spreading and E x B Shear

Description: An integrated program of gyrokinetic particle simulation and theory has been developed to investigate several outstanding issues in both turbulence and neoclassical physics. Gyrokinetic particle simulations of toroidal ion temperature gradient (ITG) turbulence spreading using the GTC code and its related dynamical model have been extended to the case with radially increasing ion temperature gradient, to study the inward spreading of edge turbulence toward the core. Due to turbulence spreading from the edge, the turbulence intensity in the core region is significantly enhanced over the value obtained from simulations of the core region only. Even when the core gradient is within the Dimits shift regime (i.e., self-generated zonal flows reduce the transport to a negligible value), a significant level of turbulence and transport is observed in the core due to spreading from the edge. The scaling of the turbulent front propagation speed is closer to the prediction from our nonlinear diffusion model than one based on linear toroidal coupling. A calculation of ion poloidal rotation in the presence of sharp density and toroidal angular rotation frequency gradients from the GTC-Neo particle simulation code shows that the results are significantly different from the conventional neoclassical theory predictions. An energy conserving set of a fully electromagnetic nonlinear gyrokinetic Vlasov equation and Maxwell's equations, which is applicable to edge turbulence, is being derived via the phase-space action variational Lie perturbation method. Our generalized ordering takes the ion poloidal gyroradius to be on the order of the radial electric field gradient length.
Date: December 21, 2004
Creator: Hahm, T.S.; Lin, Z.; Diamond, P.H.; Rewoldt, G.; Wang, W.X.; Ethier, S. et al.
Partner: UNT Libraries Government Documents Department

YUMMY: The Yucca Mountain MCNP-Library

Description: Point-wise libraries provided with the MCNP code contain neutron data for a limited number of temperatures. However, it is important to have the option of using data from a wide range of temperatures for transport calculations. For this purpose, a multi-temperature, ACE-format neutron library was generated for 134 nuclides, as requested by Yucca Mountain Project (YMP) staff. The library is referred to as YUMMY (YUcca Mountain MCNP-librarY). The neutron cross section data are based on ENDF/B-V or ENDF/B-VI evaluations that were requested by YMP staff. This document provides the details of the new library and its use in criticality safety benchmark problems, a Pressurized Water Reactor design and waste package models in MCNP4C.
Date: December 10, 2004
Creator: Alpan, FA
Partner: UNT Libraries Government Documents Department

Higher Order Lagrange Finite Elements In M3D

Description: The M3D code has been using linear finite elements to represent multilevel MHD on 2-D poloidal planes. Triangular higher order elements, up to third order, are constructed here in order to provide M3D the capability to solve highly anisotropic transport problems. It is found that higher order elements are essential to resolve the thin transition layer characteristic of the anisotropic transport equation, particularly when the strong anisotropic direction is not aligned with one of the Cartesian coordinates. The transition layer is measured by the profile width, which is zero for infinite anisotropy. It is shown that only higher order schemes have the ability to make this layer converge towards zero when the anisotropy gets stronger and stronger. Two cases are considered. One has the strong transport direction partially aligned with one of the element edges, the other doesn't have any alignment. Both cases have the strong transport direction misaligned with the grid line by some angles.
Date: December 17, 2004
Creator: Chen, J.; Strauss, H.R.; Jardin, S.C.; Park, W.; Sugiyama, L.E.; Fu, G. et al.
Partner: UNT Libraries Government Documents Department

Interfacial Reduction - Oxidation Mechanisms Governing Fate and Transport of Contaminants in the Vadose Zone

Description: Many soil contamination sites at Department of Energy installations contain radionuclides and toxic metals such as technetium (Tc), uranium (U) and chromium (Cr). In Situ Gaseous Reduction (ISGR) using dilute hydrogen sulfide (H2S) as reductant is a technology uniquely suitable for the vadose zone soil remediation to reduce and immobilize these contaminants. It is conceivable that the ISGR approach can be applied either to immobilize pre-existing contaminants or to create a reductive permeable reactive barrier (PRB) through hydrogen sulfide gas treatment of soils for contaminant interception. This project aims to improve our understanding of the complex interactions among the contaminants (U and Tc), H2S, and various soil constituents. The collaborative effort involving the University of Missouri-Columbia, Pacific Northwest National Laboratory, and Illinois Institute of Technology will provide the knowledge needed to further develop and optimize the ISGR technology. Specific research tasks include: (a) examine the reduction kinetics of Tc(VII) and U(VI) by H2S; (b) measure the reduction kinetics of Tc(VII) and U(VI) by iron sulfides; (c) characterize the speciation of immobilized Tc and U and investigate the immobilization mechanisms; (d) assess the long-term stability of the contaminants immobilized by the ISGR treatment; and (e) validate the pure phase experimental results under natural soil conditions.
Date: December 1, 2004
Creator: Deng, Baolin
Partner: UNT Libraries Government Documents Department

Interaction of Ambipolar Plasma Flow with Magnetic Islands in a Quasi-axisymmetric Stellarator

Description: A reference equilibrium for the U.S. National Compact Stellarator Experiment is predicted to be sufficiently close to quasi-symmetry to allow the plasma to flow in the toroidal direction with little viscous damping, yet to have sufficiently large deviations from quasi-symmetry that nonambipolarity significantly affects the physics of the shielding of resonant magnetic perturbations by plasma flow. The unperturbed velocity profile is modified by the presence of an ambipolar potential, which broadens the profile and improves the shielding near the plasma edge. In the presence of a resonant magnetic field perturbation, nonambipolar transport produces a radial current, and the resulting jxB force resists departures from the ambipolar velocity and enhances the shielding.
Date: December 17, 2004
Creator: Reiman, A.; Zarnstorff, M.; Mikkelsen, D.; Owen, L.; Mynick, H.; Hudson, S. et al.
Partner: UNT Libraries Government Documents Department

Final Report for Award DE-FG02-99ER54554 Kinetics of Electron Fluxes in Low-Pressure Nonthermal Plasmas

Description: This grant has focused on the study of several aspects of electron kinetics in low pressure plasmas. Entirely new effects arise from the fact that the electron kinetics is governed by non-local effects, in which the electron distribution function is not equilibrium with the local electric field but is governed by spatial transport effects. In this grant, we were able to demonstrate several previously un-studied effects which are a direct result of the nonlocal transport. These are: (1) The existence of a ''convective cell' in electron phase space. The phenomenon was observed and studied in CW plasma conditions. (2) The occurrence of non-collisional cooling of electrons through an effect known as ''diffusive cooling''.
Date: December 13, 2004
Creator: Kortshagen, Uwe
Partner: UNT Libraries Government Documents Department

Field-Scale In Situ Measurements of Vadose Zone Flow and Transport Using Multiple Tracers at INEEL Vadose Zone Research Park (VZRP)

Description: This study is aimed at obtaining a better understanding of vadose zone flow and transport processes at the field scale and establishing defensible links between laboratory- and field-derived transport parameters for conservative and reactive elements in the vadose zone. The study site (Vadose Zone Research Park [VZRP] at INEEL) provides a three dimensional instrumentation array strategically surrounding a new infiltration pond slated for initial use in the upcoming year, and the Big Lost River, and intermittent stream proximal to the infiltration ponds. The proposed research will utilize the infiltration ponds and the Big Lost River to study the effects of fluid flux, water chemistry and degree of saturation on contaminant transport in the vadose zone. Our research plan has four major objectives: (1) determine the transport of conservative and reactive solute and colloid tracers through the vadose zone and local perched water zones; (2) examine isotopic variations of U and Sr and compare these to introduced sorbing and non-sorbing tracers; (3) develop and calibrate a conceptual flow and transport model, and (4) examine the effects of flow and geochemical transients on tracer transport.
Date: December 1, 2004
Creator: Asmerom, Yemane
Partner: UNT Libraries Government Documents Department

A New Framework for Adaptive Sampling and Analysis During Long-Term Monitoring and Remedial Action Management

Description: The Argonne team has gathered available data on monitoring wells and measured hydraulic heads from the Argonne 317/319 site and sent it to UIUC. Xiaodong Li, a research assistant supported by the project, has reviewed the data and has fit initial spatiotemporal statistical models to it. Another research assistant, Yonas Demissie, has completed generation of the artificial data that will be used for model development and testing. In order to generate the artificial data a detailed groundwater flow and contaminant transport model was developed based upon characteristics of the 317/319 site. The model covers a multi-year time horizon that includes both before and after planting of the trees. As described in the proposal, the artificial data is created by adding ''measurement'' error to the ''true'' value from the numerical model. To date, only simple white noise error models have been considered. He is now reviewing the literature and beginning to develop a hierarchical modeling approach for the artificial data. Abhishek Singh, a third research assistant supported by the project, is implementing learning models for learning users preferences in an interactive genetic algorithm for solving the inverse problem. Meghna Babbar, the fourth research assistant supported by the project, has been improving the user interface for the interactive genetic algorithm and preparing a long-term monitoring design problem for testing the approach. Gayathri Gopalakrishnan, the last research assistant who is partially supported by the project, has collected substantial data from the 317/319 phytoremediation site at Argonne and has begun learning approaches for modeling these data.
Date: December 1, 2004
Creator: Minsker, Barbara
Partner: UNT Libraries Government Documents Department

Research Leading to High Throughput Manufacturing of Thin-Film CdTe PV Modules: Annual Technical Report, September 2003-September 2004

Description: First Solar is actively commercializing CdTe-based thin-film photovoltaics. During the past year, major additions of production capability have been completed, as well as process improvements to achieve higher throughput and efficiency and greater durability. This report presents the results of Phase II of the subcontract, entitled ''Research Leading to High Throughput Manufacturing of Thin-Film CdTe PV Modules.'' The subcontract supports several important aspects needed for high-volume manufacturing of high-efficiency modules, including exploration of large-area advanced front-contact window layers, improvements of the semiconductor deposition system, advancement in understanding of post-deposition processing steps and accelerated life testing methods, and progress in the environmental, health and safety programs. Work under this subcontract contributes to the overall manufacturing operation. During Phase II, average module efficiency (total area) on the production line was improved from 7.9% to 8.6% due primarily to process optimization. At the same, time production volume for commercial sales increased from 2.5 MW in 2003 to an estimated 6 MW in 2004. Much of the new 25 MW/yr production line has been qualified, and production volume is steadily increasing.
Date: December 1, 2004
Creator: Powell, R. C.
Partner: UNT Libraries Government Documents Department

Characterization of U(VI) Sorption-Desoprtion Processes and Model Upscaling

Description: In order to apply predictive reactive transport models to the Hanford site, detailed knowledge of the speciation of contaminants is required. Important speciation parameters include: (1) oxidation state; (2) the local molecular structure surrounding contaminant elements; (3) the type and binding of a contaminant ion sorption complex (if adsorbed); (4) the type(s) of phase within which a contaminant is structurally incorporated [e.g., present in a three-dimensional precipitate(s)]; (5) the phase associations of a contaminant; (6) the microscopic distribution of a contaminant within sediments and soils. In the present study, we have used synchrotron-based X-ray spectroscopic methods to study the speciation of U and Cu in contaminated soil and sediment samples from the Hanford Site. To complement and complete our initial XAFS investigation of U speciation in contaminated vadose zone sediments below tank BX-102, we have also performed mXRD studies of two sediment sample to identify the specific U(VI)-silicate phase present. Samples from the 300 Area were examined by mSXRF to determine the microscopic distribution and element associations of Cu and U. These samples were also analyzed by U LIII- and Cu K-edge XAFS spectroscopy to determine the chemical speciation of these elements.
Date: December 1, 2004
Creator: Ball, William P.
Partner: UNT Libraries Government Documents Department

An Evaluation of UDP Transport Protocols

Description: Although the speed of LAN and WAN networking is growing at an exponential rate, the applications that use those networks have not followed suit. With fiber optic interconnects, gigahertz processor speeds, and 10 gigabit per second network interface cards, hardware does not seem to be the limiting factor. It is becoming increasingly obvious that the protocols that are the basis of networking today are ill-suited to a new generation of networking technology. For this reason, Oak Ridge National Laboratory is particularly interested in improving bulk transfers over high-bandwidth, high-latency networks because of its involvement in storage and in the transfer of data for cutting-edge scientific applications. This report summarizes our evaluation of a new group of protocols specifically designed to get more useful bandwidth from today's high speed, wide area networks.
Date: December 21, 2004
Creator: Carter, S
Partner: UNT Libraries Government Documents Department

Analysis of Savannah Survey Sediment Collections of 30 Sep 04

Description: This report summarizes laboratory radiochemical analyses of sediment samples collected by the Defense Threat Reduction Agency during the DoD Savannah Survey operations of Sep 04. The analytic goal was to determine if Wassaw Sound sediment collections of 30 Sep 04 display evidence for local anthropogenic uranium, as distinct from the recognized regional background stemming from the Savannah River Site (SRS). Radiochemical methods were selected to maximize detection sensitivity for such anthropogenic uranium. Within the suite of twelve collections, there would be evidence for a localized source if individual collections were to differ from the population as a whole. If in fact non-natural uranium were observed, definitive determination of whether the source was SRS effluent or a localized release would likely involve additional field sampling. These collections were logged by the LLNL Forensics Science Center, photographed, and laboratory chain-of-custody was begun. The inventory received at LLNL is reported in Table 1. The separate collections were not assigned any relative priority among them. LLNL has separately reviewed detailed records of the item in question, and determined what materials are involved and what radiochemical assays are of value. Attempting quantitative estimates of source-item material release, transport, and collection levels would be quite uncertain. Rather, present assays examine for departure from natural background isotopic compositions. To summarize the findings, analyses for all collections displayed natural uranium isotopic composition--considering the {sup 238}U/{sup 235}U and {sup 236}U/{sup 235}U ratios--within measurement uncertainties, which were quite low. No one collection or set of collections stood apart from the others in its uranium isotopes. These {sup 238}U/{sup 235}U data uncertainty levels also determined with 99.5% confidence (a three-standard-deviation determination) that no more than 0.46% of the total uranium present in the Savannah Survey collections could be depleted uranium. Based on gamma spectroscopy assays of {sup 137}Cs specific activity (Becquerels ...
Date: December 3, 2004
Creator: Wimer, N; Hutcheon, I; Esser, B & Ramon, E
Partner: UNT Libraries Government Documents Department

Final Report of the Grant: ''Vertical Transport and Mixing in Complex Terrain Airsheds''

Description: Stable stratification associated with nocturnal thermal circulation in areas of complex terrain leads to interesting and important phenomena that govern local meteorology and contaminant dispersion. Given that most urban areas are in complex topography, understanding and prediction of such phenomena are of immediate practical importance. This project dealt with theoretical, laboratory, numerical and field experimental studies aimed at understanding stratified flow and turbulence phenomena in urban areas, with particular emphasis on flow, turbulence and contaminant transport and diffusion in such flows. A myriad of new results were obtained and some of these results were used to improve the predictive capabilities of the models.
Date: December 29, 2004
Creator: Berman, Harindra Joseph Fernando James Anderson Don Boyer Neil
Partner: UNT Libraries Government Documents Department