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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
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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
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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
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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
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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
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Capabilities, methodologies, and use of the cambio file-translation application

Lasche, George

This report describes the capabilities, methodologies, and uses of the Cambio computer application, designed to automatically read and display nuclear spectral data files of any known format in the world and to convert spectral data to one of several commonly used analysis formats. To further assist responders, Cambio incorporates an analysis method based on non-linear fitting techniques found in open literature and implemented in openly published source code in the late 1980s. A brief description is provided of how Cambio works, of what basic formats it can currently read, and how it can be used. Cambio was developed at Sandia National Laboratories and is provided as a free service to assist nuclear emergency response analysts anywhere in the world in the fight against nuclear terrorism.

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TYPE SAND Report YEAR 2007
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Macro-meso-microsystems integration in LTCC : LDRD report

Rohde, Steven B.; Okandan, Murat; Pfeifer, Kent B.; De Smet, Dennis; Patel, Kamlesh; Ho, Clifford K.; Nordquist, Christopher D.; Walker, Charles; Rohrer, Brandon R.; Buerger, Stephen P.; Turner, Timothy; Wroblewski, Brian W.

Low Temperature Cofired Ceramic (LTCC) has proven to be an enabling medium for microsystem technologies, because of its desirable electrical, physical, and chemical properties coupled with its capability for rapid prototyping and scalable manufacturing of components. LTCC is viewed as an extension of hybrid microcircuits, and in that function it enables development, testing, and deployment of silicon microsystems. However, its versatility has allowed it to succeed as a microsystem medium in its own right, with applications in non-microelectronic meso-scale devices and in a range of sensor devices. Applications include silicon microfluidic ''chip-and-wire'' systems and fluid grid array (FGA)/microfluidic multichip modules using embedded channels in LTCC, and cofired electro-mechanical systems with moving parts. Both the microfluidic and mechanical system applications are enabled by sacrificial volume materials (SVM), which serve to create and maintain cavities and separation gaps during the lamination and cofiring process. SVMs consisting of thermally fugitive or partially inert materials are easily incorporated. Recognizing the premium on devices that are cofired rather than assembled, we report on functional-as-released and functional-as-fired moving parts. Additional applications for cofired transparent windows, some as small as an optical fiber, are also described. The applications described help pave the way for widespread application of LTCC to biomedical, control, analysis, characterization, and radio frequency (RF) functions for macro-meso-microsystems.

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TYPE SAND Report YEAR 2007
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On the application of computational fluid dynamics codes for liquefied natural gas dispersion

Journal of Hazardous Materials

Luketa-Hanlin, Anay; Koopman, Ronald P.; Ermak, Donald L.

Computational fluid dynamics (CFD) codes are increasingly being used in the liquefied natural gas (LNG) industry to predict natural gas dispersion distances. This paper addresses several issues regarding the use of CFD for LNG dispersion such as specification of the domain, grid, boundary and initial conditions. A description of the k-ε model is presented, along with modifications required for atmospheric flows. Validation issues pertaining to the experimental data from the Burro, Coyote, and Falcon series of LNG dispersion experiments are also discussed. A description of the atmosphere is provided as well as discussion on the inclusion of the Coriolis force to model very large LNG spills. © 2006 Elsevier B.V. All rights reserved.

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TYPE Journal Article YEAR 2007
ScopusOSTI

Markov Models and the Ensemble Kalman Filter for Estimation of Sorption Rates

Sandia journal manuscript; Not yet accepted for publication

Vugrin, Eric; Mckenna, Sean A.; Vugrin, Kay E.W.

Non-equilibrium sorption of contaminants in ground water systems is examined from the perspective of sorption rate estimation. A previously developed Markov transition probability model for solute transport is used in conjunction with a new conditional probability-based model of the sorption and desorption rates based on breakthrough curve data. Two models for prediction of spatially varying sorption and desorption rates along a one-dimensional streamline are developed. These models are a Markov model that utilizes conditional probabilities to determine the rates and an ensemble Kalman filter (EKF) applied to the conditional probability method. Both approaches rely on a previously developed Markov-model of mass transfer, and both models assimilate the observed concentration data into the rate estimation at each observation time. Initial values of the rates are perturbed from the true values to form ensembles of rates and the ability of both estimation approaches to recover the true rates is examined over three different sets of perturbations. The models accurately estimate the rates when the mean of the perturbations are zero, the unbiased case. Finally, for the cases containing some bias, addition of the ensemble Kalman filter is shown to improve accuracy of the rate estimation by as much as an order of magnitude.

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TYPE Presentation YEAR 2007
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Advanced imaging of multiple mRNAs in brain tissue using a custom hyperspectral imager and multivariate curve resolution

Journal of Neuroscience Methods

Sutherland, Vicki L.; Timlin, Jerilyn A.; Nieman, Linda T.; Guzowski, John F.; Chawla, Monica K.; Worley, Paul F.; Roysam, Badri; McNaughton, Bruce L.; Sinclair, Michael B.; Barnes, Carol A.

Simultaneous imaging of multiple cellular components is of tremendous importance in the study of complex biological systems, but the inability to use probes with similar emission spectra and the time consuming nature of collecting images on a confocal microscope are prohibitive. Hyperspectral imaging technology, originally developed for remote sensing applications, has been adapted to measure multiple genes in complex biological tissues. A spectral imaging microscope was used to acquire overlapping fluorescence emissions from specific mRNAs in brain tissue by scanning the samples using a single fluorescence excitation wavelength. The underlying component spectra obtained from the samples are then separated into their respective spectral signatures using multivariate analyses, enabling the simultaneous quantitative measurement of multiple genes either at regional or cellular levels. © 2006 Elsevier B.V. All rights reserved.

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TYPE Journal Article YEAR 2007
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Wire initiation critical for radiation symmetry in Z-pinch-driven dynamic hohlraums

Physical Review Letters

Sanford, T.W.L.; Jennings, C.A.; Rochau, G.A.; Rosenthal, Stephen E.; Sarkisov, G.S.; Sasorov, P.V.; Stygar, William A.; Bennett, Lawrence F.; Bliss, David E.; Chittenden, J.P.; Cuneo, Michael E.; Haines, M.G.; Leeper, Ramon J.; Mock, R.C.; Nash, Thomas J.; Peterson, D.L.

Axial symmetry in x-ray radiation of wire-array z pinches is important for the creation of dynamic hohlraums used to compress inertial-confinement-fusion capsules. We present the first evidence that this symmetry is directly correlated with the magnitude of the negative radial electric field along the wire surface. This field (in turn) is inferred to control the initial energy deposition into the wire cores, as well as any current shorting to the return conductor. © 2007 The American Physical Society.

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TYPE Conference YEAR 2007
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Hierarchical probabilistic regionalization of volcanism for Sengan region, Japan

Geotechnical and Geological Engineering

Kulatilake, Pinnaduwa H.S.W.; Park, Jinyong; Balasingam, Pirahas; Mckenna, Sean A.

A 1 km square regular grid system created on the Universal Transverse Mercator zone 54 projected coordinate system is used to work with volcanism related data for Sengan region. The following geologic variables were determined as the most important for identifying volcanism: geothermal gradient, groundwater temperature, heat discharge, groundwater pH value, presence of volcanic rocks and presence of hydrothermal alteration. Data available for each of these important geologic variables were used to perform directional variogram modeling and kriging to estimate geologic variable vectors at each of the 23949 centers of the chosen 1 km cell grid system. Cluster analysis was performed on the 23949 complete variable vectors to classify each center of 1 km cell into one of five different statistically homogeneous groups with respect to potential volcanism spanning from lowest possible volcanism to highest possible volcanism with increasing group number. A discriminant analysis incorporating Bayes' theorem was performed to construct maps showing the probability of group membership for each of the volcanism groups. The said maps showed good comparisons with the recorded locations of volcanism within the Sengan region. No volcanic data were found to exist in the group 1 region. The high probability areas within group 1 have the chance of being the no volcanism region. Entropy of classification is calculated to assess the uncertainty of the allocation process of each 1 km cell center location based on the calculated probabilities. The recorded volcanism data are also plotted on the entropy map to examine the uncertainty level of the estimations at the locations where volcanism exists. The volcanic data cell locations that are in the high volcanism regions (groups 4 and 5) showed relatively low mapping estimation uncertainty. On the other hand, the volcanic data cell locations that are in the low volcanism region (group 2) showed relatively high mapping estimation uncertainty. The volcanic data cell locations that are in the medium volcanism region (group 3) showed relatively moderate mapping estimation uncertainty. Areas of high uncertainty provide locations where additional site characterization resources can be spent most effectively. The new data collected can be added to the existing database to perform future regionalized mapping and reduce the uncertainty level of the existing estimations. © Springer Science+Business Media B.V. 2006.

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TYPE Conference YEAR 2007
ScopusOSTI

Modal deposition of shock energy

Proposed for publication in Earthquake Engineering and Structural Dynamics.

Edwards, Timothy S.; Segalman, Daniel J.

A relatively new concept in the field of mechanical shock analysis has been introduced whereby an analysis is made on the work done on structures by the excitation force. The energy imparted to a structure by the excitation can then be divided into various storage and loss mechanisms within the structure. These energies can be used to both evaluate shock response severity and characterize the underlying excitation. Previous work has illustrated the many advantages of the energy methods over traditional shock response spectrum techniques. This work will show that the energy delivered to a MDOF system is uncoupled between modes. Therefore, the total deformational energy delivered to a MDOF system is a weighted sum of the uncoupled modal contributions. This leads to the ability to compute input energy on a modal basis using uncoupled, SDOF calculations. Further, the internal storage and loss energies are also uncoupled. When the input excitation is broadband, the energy input into a MDOF structure by ground motion is dominated by that mode with the largest fraction of participating mass, often the fundamental mode of the system. This leads to the justification for treating complex structures as SDOF oscillators when using energy methods to evaluate both the underlying excitation and the structural response.

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TYPE Journal Article YEAR 2007
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Results 82401–82600 of 99,299
Results 82401–82600 of 99,299