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A user's guide to the GoldSim/BLT-MS integrated software package:a low-level radioactive waste disposal performance assessment model

Mattie, Patrick; Knowlton, Robert G.; Arnold, Bill W.

Sandia National Laboratories (Sandia), a U.S. Department of Energy National Laboratory, has over 30 years experience in the assessment of radioactive waste disposal and at the time of this publication is providing assistance internationally in a number of areas relevant to the safety assessment of radioactive waste disposal systems. In countries with small radioactive waste programs, international technology transfer program efforts are often hampered by small budgets, schedule constraints, and a lack of experienced personnel. In an effort to surmount these difficulties, Sandia has developed a system that utilizes a combination of commercially available software codes and existing legacy codes for probabilistic safety assessment modeling that facilitates the technology transfer and maximizes limited available funding. Numerous codes developed and endorsed by the United States Nuclear Regulatory Commission (NRC) and codes developed and maintained by United States Department of Energy are generally available to foreign countries after addressing import/export control and copyright requirements. From a programmatic view, it is easier to utilize existing codes than to develop new codes. From an economic perspective, it is not possible for most countries with small radioactive waste disposal programs to maintain complex software, which meets the rigors of both domestic regulatory requirements and international peer review. Therefore, revitalization of deterministic legacy codes, as well as an adaptation of contemporary deterministic codes, provides a credible and solid computational platform for constructing probabilistic safety assessment models. This document is a reference users guide for the GoldSim/BLT-MS integrated modeling software package developed as part of a cooperative technology transfer project between Sandia National Laboratories and the Institute of Nuclear Energy Research (INER) in Taiwan for the preliminary assessment of several candidate low-level waste repository sites. Breach, Leach, and Transport-Multiple Species (BLT-MS) is a U.S. NRC sponsored code which simulates release and transport of contaminants from a subsurface low-level waste disposal facility. GoldSim is commercially available probabilistic software package that has radionuclide transport capabilities. The following report guides a user through the steps necessary to use the integrated model and presents a successful application of the paradigm of renewing legacy codes for contemporary application.

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TYPE SAND Report YEAR 2007
DOIOSTI

Sandia National Laboratories California Environmental Monitoring Program Annual Report

Holland, Robert C.

The annual program report provides detailed information about all aspects of the SNL/CA Environmental Monitoring Program for a given calendar year. It functions as supporting documentation to the SNL/CA Environmental Management System Program Manual. The 2006 program report describes the activities undertaken during the past year, and activities planned in future years to implement the Environmental Monitoring Program, one of six programs that supports environmental management at SNL/CA.

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TYPE SAND Report YEAR 2007
DOIOSTI

Dynamic Fracture of a Mild Steel Plate

Sandia journal manuscript; Not yet accepted for publication

Todd, Steven N.

A detonating explosive in contact or in close proximity with a material can impart an extremely strong impulsive load that nucleates the growth of cracks and voids at multiple sites simultaneously. This paper uses experimental results to show void nucleation and fractures that developed during the impulsive loading of a mild steel plate. Additionally, a numerical simulation that matches the experimental results shows the the progression, amplitude, and interaction of the stress wave as it propagates through the thickness of the plate. Through this simulation, one can see where the fractures might initiate due to large triaxial stresses. Finally, the paper discusses the possible mechanisms that initiate and generate the fracture surfaces found in the mild steel plate experiment.

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TYPE Journal Article YEAR 2007
OSTI

Collection and processing data for high quality CCD images

Doerry, Armin W.

Coherent Change Detection (CCD) with Synthetic Aperture Radar (SAR) images is a technique whereby very subtle temporal changes can be discerned in a target scene. However, optimal performance requires carefully matching data collection geometries and adjusting the processing to compensate for imprecision in the collection geometries. Tolerances in the precision of the data collection are discussed, and anecdotal advice is presented for optimum CCD performance. Processing considerations are also discussed.

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TYPE SAND Report YEAR 2007
DOIOSTI

Nanoporous microbead supported bilayers: stability, physical characterization, and incorporation of functional transmembrane proteins

Brozik, Susan M.

The introduction of functional transmembrane proteins into supported bilayer-based biomimetic systems presents a significant challenge for biophysics. Among the various methods for producing supported bilayers, liposomal fusion offers a versatile method for the introduction of membrane proteins into supported bilayers on a variety of substrates. In this study, the properties of protein containing unilamellar phosphocholine lipid bilayers on nanoporous silica microspheres are investigated. The effects of the silica substrate, pore structure, and the substrate curvature on the stability of the membrane and the functionality of the membrane protein are determined. Supported bilayers on porous silica microspheres show a significant increase in surface area on surfaces with structures in excess of 10 nm as well as an overall decrease in stability resulting from increasing pore size and curvature. Comparison of the liposomal and detergent-mediated introduction of purified bacteriorhodopsin (bR) and the human type 3 serotonin receptor (5HT3R) are investigated focusing on the resulting protein function, diffusion, orientation, and incorporation efficiency. In both cases, functional proteins are observed; however, the reconstitution efficiency and orientation selectivity are significantly enhanced through detergent-mediated protein reconstitution. The results of these experiments provide a basis for bulk ionic and fluorescent dye-based compartmentalization assays as well as single-molecule optical and single-channel electrochemical interrogation of transmembrane proteins in a biomimetic platform.

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TYPE SAND Report YEAR 2007
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Neutron spectrometer for improved SNM search

Aigeldinger, Georg

With the exception of large laboratory devices with very low sensitivities, a neutron spectrometer have not been built for fission neutrons such as those emitted by special nuclear materials (SNM). The goal of this work was to use a technique known as Capture Gated Neutron Spectrometry to develop a solid-state device with this functionality. This required modifications to trans-stilbene, a known solid-state scintillator. To provide a neutron capture signal we added lithium to this material. This unique triggering signal allowed identification of neutrons that lose all of their energy in the detector, eliminating uncertainties that arise due to partial energy depositions. We successfully implemented a capture gated neutron spectrometer and were able to distinguish an SNM like fission spectrum from a spectrum stemming from a benign neutron source.

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TYPE SAND Report YEAR 2007
DOIOSTI

Fuel traps: mapping stability via water association

Sabo, Dubravko S.; Greathouse, Jeffery A.; Leung, Kevin; Cygan, Randall T.; Alam, Todd M.; Varma, Sameer; Martin, Marcus G.

Hydrogen storage is a key enabling technology required for attaining a hydrogen-based economy. Fundamental research can reveal the underlying principles controlling hydrogen uptake and release by storage materials, and also aid in characterizing and designing novel storage materials. New ideas for hydrogen storage materials come from exploiting the properties of hydrophobic hydration, which refers to water s ability to stabilize, by its mode of association, specific structures under specific conditions. Although hydrogen was always considered too small to support the formation of solid clathrate hydrate structures, exciting new experiments show that water traps hydrogen molecules at conditions of low temperatures and moderate pressures. Hydrogen release is accomplished by simple warming. While these experiments lend credibility to the idea that water could form an environmentally attractive alternative storage compound for hydrogen fuel, which would advance our nation s goals of attaining a hydrogen-based economy, much work is yet required to understand and realize the full potential of clathrate hydrates for hydrogen storage. Here we undertake theoretical studies of hydrogen in water to establish a firm foundation for predictive work on clathrate hydrate H{sub 2} storage capabilities. Using molecular simulation and statistical mechanical theories based in part on quantum mechanical descriptions of molecular interactions, we characterize the interactions between hydrogen and liquid water in terms of structural and thermodynamic properties. In the process we validate classical force field models of hydrogen in water and discover new features of hydrophobic hydration that impact problems in both energy technology and biology. Finally, we predict hydrogen occupancy in the small and large cages of hydrogen clathrate hydrates, a property unresolved by previous experimental and theoretical work.

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TYPE SAND Report YEAR 2007
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Interim report:feasibility of microscale glucose reforming for renewable hydrogen

Norman, Kirsten

Micro-scale aqueous steam reforming of glucose is suggested as a novel method of H{sub 2} production for micro fuel cells. Compact fuel cell systems are a viable alternative to batteries as a portable electrical power source. Compared with conventional lithium polymer batteries, hydrocarbon powered fuel cells are smaller, weigh less, and have a much higher energy density. The goal of this project is to develop a hydrocarbon powered microfuel processor capable of driving an existing microfuel cell, and this interim report provides a summary of the engineering information for microscale reforming of carbohydrates and the summarizes the work completed as of September 2006. Work on this program will continue. Gas analysis of the gas evolved from glucose breakdown using a quadrupole mass spectrometer is now possible due do significant modifications to the vacuum chamber and to the mass spectrometer electronics. Effective adhesion of Pt/Al{sub 2}O{sub 3} to 316SS microstructured catalyst plates is still under investigation. Electrophoretic and dip coat methods of catalyst deposition have produced coatings with poor adhesion and limited available Pt surface area.

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TYPE SAND Report YEAR 2007
DOIOSTI
Results 82401–82500 of 99,299
Results 82401–82500 of 99,299