We use molecular dynamics simulations of the Kremer–Grest (KG) bead–spring model of polymer chains of length between 10 and 500, and a closely related analogue that allows for chain crossing, to clearly delineate the effects of entanglements on the length-scale-dependent chain relaxation in polymer melts. We analyze the resulting trajectories using the Rouse modes of the chains and find that entanglements strongly affect these modes. The relaxation rates of the chains show two limiting effective monomeric frictions, with the local modes experiencing much lower effective friction than the longer modes. The monomeric relaxation rates of longer modes vary approximately inversely with chain length due to kinetic confinement effects. The time-dependent relaxation of Rouse modes has a stretched exponential character with a minimum of stretching exponent in the vicinity of the entanglement chain length. None of these trends are found in models that allow for chain crossing. As a result, these facts, in combination, argue for the confined motion of chains for time scales between the entanglement time and their ultimate free diffusion.
This report presents the results of a series of cable fire-retardant coating tests sponsored by the US Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research and performed at Sandia National Laboratories in conjunction with the National Institute of Standards and Technology (NIST). The goal of the tests was to assess the effects of three commercially available fire-retardant cable coating materials on cable thermal and electrical response behavior under fire-exposure conditions. The specific test objectives were to assess, under severe radiant heating conditions, how the coating materials impacted (1) cable thermal response and (2) electrical integrity behavior. The tests were not explicitly designed to assess the impact of the coatings on cable flammability, although some insights relative to the burning behavior of the coating materials themselves and cable ignition times were gained. NIST is currently investigating these attributes under the Cable Heat Release, Ignition, and Spread in Tray Installations During Fire (CHRISTIEFIRE) program (NUREG/CR-7010). The cables used in construction of the test articles were all seven-conductor 12AWG (American wire gage) control or power type copper conductor electrical cables. Two cable insulation types were represented, a polyethylene thermoplastic material and a cross-linked polyethylene thermoset material. Both cable types used have been tested extensively in recent NRC-sponsored experimental programs involving both circuit failure modes and effects testing and fire growth testing. The test articles included uncoated cables and cables coated with one of three fire-retardant coating materials: Carboline Intumastic 285, Flamemastic F-77, and Vimasco 3i. Test configurations included single lengths of cables, bundles of seven cables, and bundles of ten cables. The tests show that, under certain conditions, the fire-retardant coatings provide a substantial benefit relative to delays in cable heating, ignition and electrical failure times. However, as has been seen in prior test programs, the performance varied substantially among the coating products. The current tests also show that the benefit gained by the coatings was heavily dependent on the thermal mass of the coated cable system. Low thermal mass systems, such as the single lengths of coated cable, saw essentially no net benefit from application of the coatings. Intermediate mass systems, represented by the seven-cable bundles, saw some benefit from application of the coatings, but the benefit was inconsistent, and some cables in the bundles saw essentially no delay in thermal response or time to failure. For the larger thermal mass systems, represented by the ten-cable bundles, the benefit of the coatings was both more pronounced and more consistent with all coatings providing a measurable benefit.
The current system reaction to the loss of a single MPI process is to kill all the remaining processes and restart the application from the most recent checkpoint. This approach will become unfeasible for future extreme scale systems. We address this issue using an emerging resilient computing model called Local Failure Local Recovery (LFLR) that provides application developers with the ability to recover locally and continue application execution when a process is lost. We discuss the design of our software framework to enable the LFLR model using MPI-ULFM and demonstrate the resilient version of MiniFE that achieves a scalable recovery from process failures.
The GADRAS Development project comprises several elements that are all related to the Detector Response Function (DRF), which is the core of GADRAS. An ongoing activity is implementing continuous improvements in the accuracy and versatility of the DRF. The ability to perform rapid computation of the response of gammaray detectors for 3-D descriptions of source objects and their environments is a good example of a recent utilization of this versatility. The 3-D calculations, which execute several orders of magnitude faster than competing techniques, compute the response as an extension of the DRF so the radiation transport problem is never solved explicitly, thus saving considerable computational time. Maintenance of the Graphic User Interface (GUI) and extension of the GUI to enable construction of the 3-D source models is included in tasking for the GADRAS Development project. Another aspect of this project is application of the isotope identification algorithms for search applications. Specifically, SNL is tasked with development of an isotope-identification based search capability for use with the RSL-developed AVID system, which supports simultaneous operation of numerous radiation search assets. A Publically Available (PA) GADRAS-DRF application, which eliminates sensitive analysis components, will soon be available so that the DRF can be used by researchers at universities and corporations.
On September 9, 2014, Sandia National Laboratories, American Gas Association, and Toyota, in support of the U.S. Department of Energy's Fuel Cell Technologies and Vehicle Technologies Offices, convened stakeholders across the hydrogen and natural gas communities to consider opportunities and challenges at the intersection of their development as alternative transportation fuels. Although natural gas and hydrogen have an obvious intersection — natural gas is the feedstock for 95% of the hydrogen produced in the U.S. — little attention has been given to how these fuels can evolve in the context of each other. This workshop explored infrastructure requirements, regional trends, and market opportunities at the intersection of hydrogen fuel cell and natural gas use for on road transportation. The goal of the workshop was to provide background and context for thinking through the dynamic evolution of these two transportation options in tandem, and to identify opportunities that can support the synergistic development of both fuels.
This report documents deep borehole disposal research during FY2014, as directed by U.S. Department of Energy (DOE) Used Fuel Disposition (UFD) Campaign. These research efforts are principally directed at advancing the deep borehole disposal project to the implementation of a full-scale Research, Development, and Demonstration (RD&D) project. Activities of particular relevance to this goal include evaluation of guidelines for selection of a deep borehole field test site, analyses of deep borehole disposal of alternative waste forms, and technical planning for borehole seals research.
Multi-objective optimization is used to find a nondominated set of solutions for two conflicting performance metrics or objective functions. These functions are dependent variables in the system, controlled by a set of independent variables called decision variables. The decision variables represent the inputs to the problem, chosen by the system designer, and are values listed in the solution set. In this study, a multi-objective genetic algorithm compared insulated-gate bipolar transistor (IGBT) failure rate to filter and cooling system costs. This study demonstrated the use of multi-objective optimization for energy storage systems. IGBT failure rate was compared to its associated filter and cooling-system costs as part of the DC-AC inverter power electronics system in a battery energy storage system (BESS). The independent or decision variables were determined to be switching frequency and thermal resistance of a heat sink, Rsink. The final results indicated that high values of switching frequency increased the effects of Rsink. Future work will add additional objective functions and decision variables to the study to optimize additional components in the power electronics system and BESS.
Iron nanoparticles have a number of magnetic properties that make them a potentially useful material for transformer applications. These desirable traits include high saturation magnetization, high susceptibility, and very low magnetic hysteresis. Before iron nanoparticles can even be tested for applicability, however, a number of scientific hurdles must be overcome. First an affordable and scalable synthetic approach must be developed, and the results of these large scale reactions must be fashioned into a solid material. To be of use, this solid material must have very high loading of iron nanoparticles and must be relatively easy to form into desired shapes. To achieve these goals, iron nanoparticles were synthesized by the thermal decomposition of iron pentacarbonyl in the presence of dodecylamine which bound to the surface of the particles. This reaction was scaled up to a multi-gram scale with only minor changes in size and shape control. These particles were then fashioned into “matrix-free nanocomposites”, where the particles were cross-linked to each other. This was achieved by first exchanging the surface coating for a combination of hexylamine and 1,6-diaminohexane. The diamine provided primary amines on the particle surface that were available for further reaction. These were shown to be capable of reacting with a triepoxide cross-linker to form a hard, solid material, analogous to the cure of a common epoxy adhesive. Loading of up to 80% iron by mass (about 43% by volume) was achieved.
This report has been written for the Department of Energy’s Energy Policy and Systems Analysis Office to inform their writing of the Quadrennial Energy Review in the area of energy resilience. The topics of measuring and increasing energy resilience are addressed, including definitions, means of measuring, and analytic methodologies that can be used to make decisions for policy, infrastructure planning, and operations. A risk-based framework is presented which provides a standard definition of a resilience metric. Additionally, a process is identified which explains how the metrics can be applied. Research and development is articulated that will further accelerate the resilience of energy infrastructures.
Reflective particle tags derive their unique identities through utilization of thousands of microscopic reflective elements randomly suspended in a clear adhesive matrix. For verification of a tag's authenticity, an illumination/imaging system is used to "read" information about precise positions and orientations of faceted particles. SNL developed the original Reflective Particle Tag (RPT) system, comprising a tag and an imager, in the 1990's to identify treaty-accountable items. Since then, the RPT system has evolved with advances in computing, imaging, and materials, and is considered a robust, low-cost, hard-to-counterfeit passive tagging system for treaty verification. However, a limitation of the current system is the need to mechanically dock the reader with the tag, which prevents its use in many situations. This paper discusses R&D at SNL to develop a non-contact handheld imaging system that will allow RPT system use in new scenarios and allows automation.
This paper attempts to describe the options to expand the scope of the current Interagency Field Test & Evaluation (IFT&E) objectives to include wind turbine encroachment on agency missions for offshore wind development in the United States. The options described here build on the recently completed IFT&E test campaigns that took place in 2012 and 2013. Those tests, which looked at the CARSR, ASR-11, ARSR-4, and eight proposed mitigation technologies, found that wind turbines can significantly impact the ability of radars to detect aircraft and meet mission requirements above and near wind farms. One of the more immediate successes of the IF&E Program is that today, several of the infill radar technologies which were tested, took the results of their IF&TE performance to move well beyond Technology Readiness Level 6/7 and some have been deployed and are operating at airports in the United Kingdom (UK). As well, the UK Ministry of Defense (MOD) has deployed the replacement radar which was tested to address specific concerns with especially concerning offshore wind farms. The UK MOD continues to test and hopes to refine these systems so that identified shortfalls in surveillance capability and operations which remain can be addressed. Wind energy has been steadily growing in the U.S. With a current capacity of over 60 GW today and the expectation that this capacity will need to grow to 300 GW to meet the U.S. Department of Energy's (DOE) goal of 20% wind energy in the future, offshore wind farms are gaining more attention. The specific impacts of wind turbine interference on maritime radars have not been determined at this time. However, the DOE did fund a study conducted by the University of Texas at Austin entitled, "Assessment of Offshore Wind Farm Effects on Sea Surface, Subsurface and Airborne Electronic Systems," that focused on identifying the broader Wind-Turbine/Radar Interference: Offshore Test Options SAND2014-17870 effects of electromagnetic interference expected to be caused by offshore wind farms.' A review of that study would be worth the reader's time. And while no comprehensive field studies have been accomplished, it is worth noting that many mitigation solutions that were tested I the IFT&E Program are derived from short-range maritime radar systems. The Wind and Water Power Technologies Office (WWPTO), within the DOE Office of Energy Efficiency and Renewable Energy, supports the development, deployment, and commercialization of wind and water power technologies. This report is funded by the WWPTO.
The ASC CSSE project Kelpie is a research and development project focused on developing a distributed, in-memory data management system that can be leveraged in a number of high-performance computing (HPC) applications. After FY13s demonstration that a key/value data store could be implemented on top of the Nessie RDMA/RPC library, we began refactoring Kelpie in FY14 in order to make it more usable by other research teams that need it for upcoming milestones. This report provides a summary of the different efforts in FY14 that took place to make Kelpie a more usable system.
The MELCOR and MACCS computer codes require inputs for radionuclide inventory and decay heat in order to simulate severe accident phenomenology, source term, and consequences. Therefore, Sandia National Laboratories ( SNL ) has developed accurate and automated methods using SCALE 6 in conjunction with automation scripts to directly generate MELCOR and MACCS input records for radionuclide inventories and decay heating. Consistent information between the two codes is essential for realistic modeling of severe nuclear accidents it is the radionuclide inventory and decay power that are the principal safety problems of any severe accident that assumes successful reactor shutdown. SNL plans to conduct best-estimate calculations and uncertainty analyses using MELCOR and MACCS for several reactors, including units 1 - 3 of Fukushima Daiichi, which entail accurate and technically-scrutable information for the input models. The SNL methodology for generating radionuclide and decay power inputs directly from SCALE6 calculations is mostly presented in the context of supporting Fukushima modeling efforts. Furthermore, certain historical assumptions used by MELCOR and MACCS in the abstraction of radionuclide classes and their properties are reviewed, and these assumptions are compared to modern code predictions by SCALE6.
Sandia National Laboratories has prepared a cost estimate budgetary planning for the IDC Reengineering Phase 2 & 3 effort. This report provides the cost estimate and describes the methodology, assumptions, and cost model details used to create the cost estimate.
This work investigated pulsed laser deposition of Cr-doped AlN thin films for use as ferromagnetic layers in memory cells for superconducting electronics. The film morphology, crystalline structure, and magnetization were investigated as a function of laser fluence on the target and background N2 pressure during deposition. Higher laser fluence resulted in films composed of a smooth underlayer with a high density of poorly adhered, rough crystallites at the surface. Lower laser fluence reduced the density of surface crystallites significantly. X-ray diffraction showed that films grown at high laser fluence show crystalline peaks associated with AlN. Both types of films showed hysteretic magnetization curves consistent with films grown by other deposition techniques.
A significant problem in quantum computing is the development of physical realizations of algorithms that are robust against noise. One way to examine and mitigate noise would be to simulate large sets of qubits coupling to the external environment on classical computers. This is extremely challenging as quantum information processing is in some sense tied to computing resources that scale exponentially with the number of computing elements (qubits). In this LDRD, we set the foundation for a computational framework potentially allowing simulations of 1000s of qubits vs. 10s now possible. Exact wave-function-based methods demand exponentially increasing resources with system size. The method proposed, entanglement-functional theory (EFT), requires vastly fewer resources. The crucial step is to map the information contained in the wave-functions into a simpler object with associated 1.) auxiliary gate operations and 2.) entanglement functionals of this object. This is similar to the Time-dependent Density Functional Theory (TDDFT) approach that has revolutionized chemistry and materials science. Instead of dealing with the exponentially large wave-function, EFT works with a polynomially large set of projections (the density) that are easily manipulated through unitary operations. For a given set of quantum gates, an isomorphism exists that relates the sequence of events to the time-dependent density. A system of entangled qubits can be simulated at drastically reduced cost relative to existing state-of-the-art vector-state simulation codes.
The transportation operations model was used to identify options for removing stranded fuel currently in dry storage at nine shutdown reactor sites to a hypothetical consolidated storage facility. The logistical variables included the campaign duration, fuel selection priority, consist size and location of the consolidated storage and maintenance facilities. The major factors affecting the logistics of fuel removal were identified. Recommendations for optimal strategies for the transport of stranded fuel from shutdown sites are made.
We present a review and critique of several methods for the simulation of the dynamics of colloidal suspensions at the mesoscale. We focus particularly on simulation techniques for hydrodynamic interactions, including implicit solvents (Fast Lubrication Dynamics, an approximation to Stokesian Dynamics) and explicit/particle-based solvents (Multi-Particle Collision Dynamics and Dissipative Particle Dynamics). Several variants of each method are compared quantitatively for the canonical system of monodisperse hard spheres, with a particular focus on diffusion characteristics, as well as shear rheology and microstructure. In all cases, we attempt to match the relevant properties of a well-characterized solvent, which turns out to be challenging for the explicit solvent models. Reasonable quantitative agreement is observed among all methods, but overall the Fast Lubrication Dynamics technique shows the best accuracy and performance. We also devote significant discussion to the extension of these methods to more complex situations of interest in industrial applications, including models for non-Newtonian solvent rheology, non-spherical particles, drying and curing of solvent and flows in complex geometries. This work identifies research challenges and motivates future efforts to develop techniques for quantitative, predictive simulations of industrially relevant colloidal suspension processes.
Sandia National Laboratories, New Mexico is a government-owned/contractor-operated facility. Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, manages and operates the laboratory for the U.S. Department of Energy (DOE), National Nuclear Security Administration (NNSA). The DOE/NNSA, Sandia Field Office administers the contract and oversees contractor operations at the site. This annual report summarizes data and the compliance status of Sandia Corporation’s sustainability, environmental protection, and monitoring programs through December 31, 2013. Major environmental programs include air quality, water quality, groundwater protection, terrestrial surveillance, waste management, pollution prevention, environmental restoration, oil and chemical spill prevention, and implementation of the National Environmental Policy Act. Environmental monitoring and surveillance programs are required by DOE Order 231.1B, Environment, Safety, and Health Reporting (DOE 2012).
We report the design, construction, and characterization of a biaxial sample rotation stage for use in a cryogenic system for orientation-dependent studies of anisotropic electronic transport phenomena at low temperatures and high magnetic fields. Our apparatus allows for continuous rotation of a sample about two axes, both independently and simultaneously.
This report describes a model of the displacement of one hydrogen isotope within a metal hydride tube by a different isotope in the gas phase that is blown through the tube. The model incorporates only the most basic parameters to make a clear connection to the theory of open-tube gas chromatography, and to provide a simple description of how the behavior of the system scales with controllable parameters such as gas velocity and tube radius. A single tube can be seen as a building block for more complex architectures that provide higher molar flow rates or other advanced design goals.
Direction of Arrival (DOA) measurements, as with a monopulse antenna, can be compared against Doppler measurements in a Synthetic Aperture Radar ( SAR ) image to determine an aircraft's forward velocity as well as its crab angle, to assist the aircraft's navigation as well as improving high - performance SAR image formation and spatial calibration.
The thermal properties of a commercial copper-diamond composite were measured from below -50°C to above 200°C. The results of thermal expansion, heat capacity, and thermal diffusivity were reported. These data were used to calculate the thermal conductivity of the composite as a function of temperature in the thickness direction. These results are compared with estimated values based on a simple mixing rule and the temperature dependence of these physical properties is represented by curve fitting equations. These fitting equations can be used for thermal modeling of practical devices/systems at their operation temperatures. The results of the mixing rule showed a consistent correlation between the amount of copper and diamond in the composite, based on density, thermal expansion, and heat capacity measurements. However, there was a disparity between measured and estimated thermal diffusivity and thermal conductivity. These discrepancies can be caused by many intrinsic material issues such as lattice defects and impurities, but the dominant factor is attributed to the large uncertainty of the interfacial thermal conductance between diamond and copper.
The miniaturization of explosive components has driven the need for a corresponding miniaturization of the current diagnostic techniques available to measure the explosive phenomena. Laser interferometry and the use of spectrally coated optical windows have proven to be an essential interrogation technique to acquire particle velocity time history data in one- dimensional gas gun and relatively large-scale explosive experiments. A new diagnostic technique described herein allows for experimental measurement of apparent particle velocity time histories in microscale explosive configurations and can be applied to shocks/non-shocks in inert materials. The diagnostic, Embedded Fiber Optic Sensors (EFOS), has been tested in challenging microscopic experimental configurations that give confidence in the technique's ability to measure the apparent particle velocity time histories of an explosive with pressure outputs in the tenths of kilobars to several kilobars. Embedded Fiber Optic Sensors also allow for several measurements to be acquired in a single experiment because they are microscopic, thus reducing the number of experiments necessary. The future of EFOS technology will focus on further miniaturization, material selection appropriate for the operating pressure regime, and extensive hydrocode and optical analysis to transform apparent particle velocity time histories into true particle velocity time histories as well as the more meaningful pressure time histories.
A new process has been developed to characterize the endpoint energy of HERMES III on a shot-to-shot basis using standard dosimetry tools from the Sandia Radiation Measurements Laboratory. Photonuclear activation readings from nickel and gold foils are used in conjunction with calcium fluoride thermoluminescent dosimeters to derive estimated electron endpoint energies for a series of HERMES shots. The results are reasonably consistent with the expected endpoint voltages on those shots.
This white paper provides information and recommendations for an actionable and enforceable corporate policy statement on temperature set points for office and related spaces at Sandia and presents a strategy that balances the need to achieve the energy goals with optimizing employee comfort and productivity.
Herein, we study the durability of the Sandia Bi-Si oxide Glass Composite Material (GCM) waste form when formulated with different weight percent levels of AgI-MOR. The post-iodine exposure AgI-MOR material was provided to SNL by ORNL. Durability results for the GCM fabricated with 22 and 25% AgI-MOR indicate releases of Ag and I at the same low rates as 15% AgI-MOR GCM, and by the same mechanism. Iodine and Ag release is controlled by the low solubility of an amorphous, hydrated silver iodide, not by the surface-controlled dissolution of I2- loaded Ag-Mordenite. Based on this data, we postulate that much higher loading levels of AgIMOR are probable in this GCM waste form, and limits will govern by retention of mechanical integrity of the GCM versus the solubility of silver iodide.
Models are built to understand and predict the behaviors of both natural and artificial systems. Because it is always necessary to abstract away aspects of any non-trivial system being modeled, we know models can potentially leave out important, even critical elements. This reality of the modeling enterprise forces us to consider the prospective impacts of those effects completely left out of a model – either intentionally or unconsidered. Insensitivity to new structure is an indication of diminishing returns. In this work, we represent a hypothetical unknown effect on a validated model as a finite perturbation whose amplitude is constrained within a control region. We find robustly that without further constraints, no meaningful bounds can be placed on the amplitude of a perturbation outside of the control region. Thus, forecasting into unsampled regions is a very risky proposition. We also present inherent difficulties with proper time discretization of models and representing inherently discrete quantities. We point out potentially worrisome uncertainties, arising from mathematical formulation alone, which modelers can inadvertently introduce into models of complex systems.
The Site Exploitation System for Situational Awareness ( SESSA ) tool kit , developed by Sandia National Laboratories (SNL) , is a comprehensive de cision support system for crime scene data acquisition and Sensitive Site Exploitation (SSE). SESSA is an outgrowth of another SNL developed decision support system , the Building R estoration Operations Optimization Model (BROOM), a hardware/software solution for data acquisition, data management, and data analysis. SESSA was designed to meet forensic crime scene needs as defined by the DoD's Military Criminal Investigation Organiza tion (MCIO) . SESSA is a very comprehensive toolki t with a considerable amount of database information managed through a Microsoft SQL (Structured Query Language) database engine, a Geographical Information System (GIS) engine that provides comprehensive m apping capabilities, as well as a an intuitive Graphical User Interface (GUI) . An electronic sketch pad module is included. The system also has the ability to efficiently generate necessary forms for forensic crime scene investigations (e.g., evidence submittal, laboratory requests, and scene notes). SESSA allows the user to capture photos on site, and can read and generate ba rcode labels that limit transcription errors. SESSA runs on PC computers running Windows 7, but is optimized for touch - screen tablet computers running Windows for ease of use at crime scenes and on SSE deployments. A prototype system for 3 - dimensional (3 D) mapping and measur e ments was also developed to complement the SESSA software. The mapping system employs a visual/ depth sensor that captures data to create 3D visualizations of an interior space and to make distance measurements with centimeter - level a ccuracy. Output of this 3D Model Builder module provides a virtual 3D %22walk - through%22 of a crime scene. The 3D mapping system is much less expensive and easier to use than competitive systems. This document covers the basic installation and operation of th e SESSA tool kit in order to give the user enough information to start using the tool kit . SESSA is currently a prototype system and this documentation covers the initial release of the tool kit . Funding for SESSA was provided by the Department of Defense (D oD), Assistant Secretary of Defense for Research and Engineering (ASD(R&E)) Rapid Fielding (RF) organization. The project was managed by the Defense Forensic Science Center (DFSC) , formerly known as the U.S. Army Criminal Investigation Laboratory (USACIL) . ACKNOWLEDGEMENTS The authors wish to acknowledge the funding support for the development of the Site Exploitation System for Situational Awareness (SESSA) toolkit from the Department of Defense (DoD), Assistant Secretary of Defense for Research and Engineering (ASD(R&E)) Rapid Fielding (RF) organization. The project was managed by the Defense Forensic Science Center (DFSC) , formerly known as the U.S. Army Criminal Investigation Laboratory (USACIL). Special thanks to Mr. Garold Warner, of DFSC, who served as the Project Manager. Individuals that worked on the design, functional attributes, algorithm development, system arc hitecture, and software programming include: Robert Knowlton, Brad Melton, Robert Anderson, and Wendy Amai.
The numerical model, SWAN (Simulating WAves Nearshore) , was used to simulate wave conditions in Kaneohe Bay, HI in order to determine the effects of wave energy converter ( WEC ) devices on the propagation of waves into shore. A nested SWAN model was validated then used to evaluate a range of initial wave conditions: significant wave heights (H s ) , peak periods (T p ) , and mean wave directions ( MWD) . Differences between wave height s in the presence and absence of WEC device s were assessed at locations in shore of the WEC array. The maximum decrease in wave height due to the WEC s was predicted to be approximately 6% at 5 m and 10 m water depths. Th is occurred for model initiation parameters of H s = 3 m (for 5 m water depth) or 4 m (10 m water depth) , T p = 10 s, and MWD = 330deg . Subsequently, bottom orbital velocities were found to decrease by about 6%.
The goal s of this study were to develop tools to quantitatively characterize environments where wave energy converter ( WEC ) devices may be installed and to assess e ffects on hydrodynamics and lo cal sediment transport. A large hypothetical WEC array was investigated using wave, hydrodynamic, and sediment transport models and site - specific average and storm conditions as input. The results indicated that there were significant changes in sediment s izes adjacent to and in the lee of the WEC array due to reduced wave energy. The circulation in the lee of the array was also altered; more intense onshore currents were generated in the lee of the WECs . In general, the storm case and the average case show ed the same qualitative patterns suggesting that these trends would be maintained throughout the year. The framework developed here can be used to design more efficient arrays while minimizing impacts on nearshore environmen ts.
The emergence of multiple drug resistant bacteria poses threats to human health, agriculture and food safety. Annually over 100,000 deaths and up to $20 billion loss to the U.S. economy are attributed to multiple drug resistant bacteria. With only four new chemical antibiotics in the drug development pipeline, we are in dire need of new solutions to address the emerging threat of multiple drug resistance. We propose a paradigm-changing approach to address the multi-drug resistant bacteria problem by utilizing Synthetic Biology (SynBio) methodologies to create and evolve “designer” bacteriophages or phages – viruses that specifically infect bacteria – to infect and kill newly emerging pathogenic bacterial strains WITHOUT the need for chemical antibiotics. A major advantage of using phage to combat pathogenic bacteria is that phages can co-evolve with their bacterial host, and Sandia can be the first in the world to establish an industrial scale Synthetic Biology pipeline for phage directed evolution for safe, targeted, customizable solution to bacterial drug resistance. Since there is no existing phage directed evolution effort within or outside of Sandia, this proposal is suitable as a high-risk LDRD effort to create the first pipeline for such an endeavor. The high potential reward nature of this proposal will be the immediate impact in decontamination and restoration of surfaces and infrastructure, with longer term impact in human or animal therapeutics. The synthetic biology and screening approaches will lead to fundamental knowledge of phage/bacteria co-evolution, making Sandia a world leader in directed evolution of bacteriophages.
This installation report describes the May through July 2014 drilling activities performed for the installation of three multi-port soil-vapor monitoring wells (MWL-SV03, MWL-SV04, and MWL-SV05) at the Mixed Waste Landfill (MWL), which is located at Sandia National Laboratories, New Mexico (SNL/NM). SNL/NM is managed and operated by Sandia Corporation (Sandia), a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy (DOE)/National Nuclear Security Administration. The MWL is designated as Solid Waste Management Unit (SWMU) 76 and is located in Technical Area (TA) III (Figure 1-1). The locations of the three soil-vapor monitoring wells (MWL-SV03, MWL-SV04, and MWL-SV05) are shown in Figure 1-2
The Turbulent Combustion Laboratory (TCL) conducts research on combustion in turbulent flow environments. To conduct this research, the TCL utilizes several pulse lasers, a traversable wind tunnel, flow controllers, scientific grade CCD cameras, and numerous other components. Responsible for managing these different data-acquiring instruments and data processing components is the Data Acquisition (DAQ) software. However, the current system is constrained to running through VXI hardware—an instrument-computer interface—that is several years old, requiring the use of an outdated version of the visual programming language, LabVIEW. A new Acquisition System is being programmed which will borrow heavily from either a programming model known as the Current Value Table (CVT) System or another model known as the Server-Client System. The CVT System model is in essence, a giant spread sheet from which data or commands may be retrieved or written to, and the Server-Client System is based on network connections between a server and a client, very much like the Server-Client model of the Internet. Currently, the bare elements of a CVT DAQ Software have been implemented, consisting of client programs in addition to a server program that the CVT will run on. This system is being rigorously tested to evaluate the merits of pursuing the CVT System model and to uncover any potential flaws which may result in further implementation. If the CVT System is chosen, which is likely, then future work will consist of build up the system until enough client programs have been created to run the individual components of the lab. The advantages of such a System will be flexibility, portability, and polymorphism. Additionally, the new DAQ software will allow the Lab to replace the VXI with a newer instrument interface—the PXI—and take advantage of the capabilities of current and future versions of LabVIEW.
I spent the last ten weeks working in the Systems Biology department at Sandia National Laboratories in Livermore, CA. Under the direction of Zachary Bent, I helped do preliminary testing/optimization of a vacuum-driven, capture-based system for pathogen RNA transcript enrichment. I also worked on a project to create mutant Yersinia enterocolitica strains in order to test which genes are involved in intracellular pathogen virulence, as well as sequencing several Klebsiella pneumoniae samples for use by a bioinformaticist.
This summer I worked on projects that involved RNA sequencing of pathogens after an infection of host cells. The goal of these projects was to continue developing pathogen enrichment strategies for transcriptomic analysis, and also to perform hostpathogen interaction studies.
The goal behind the assigned summer project was to investigate the ability of nuclear magnetic resonance spectroscopy (NMR) to identify enantiomers of select chiral organo-fluorophosphates (OFPs) compounds which are analogs of chemical warfare agents (CWAs, e.g. Sarin). This involved investigations utilizing chiral solvating agents (CSAs) and characterizing the binding phenomena with cyclodextrins. The resolution of OFPs enantiomers using NMR would be useful for research into toxicodynamics and toxicokinetics in biological systems due to the widely differing properties of the CWA enantiomers [1]. The optimization of decontamination abilities in the case of a CWA events, with this method’s potential rapidity and robustness, as well as the development of models correlating chiral compounds with CSAs for optimal resolution are all rational benefits of this research.
The RPID Project will be implemented at all SNL facilities for activities involving the processing and/or storing of radioactive materials. This project includes activities at the Tech Area (TA) I, TA II, TA III, TA IV, TA V, Coyote Test Field, and environmental restoration sites at SNL, located in Albuquerque, New Mexico, and the Kauai Test Facility(SNL/KTF). Reference to SNL throughout this document includes facilities and activities at the Albuquerque location and at SNL/KTF.
The Sandia National Laboratories’ Internal Dosimetry Technical Basis Manual is intended to provide extended technical discussion and justification of the internal dosimetry program at SNL. It serves to record the approach to evaluating internal doses from radiobioassay data, and where appropriate, from workplace monitoring data per the Department of Energy Internal Dosimetry Program Guide DOE G 441.1C. The discussion contained herein is directed primarily to current and future SNL internal dosimetrists. In an effort to conserve space in the TBM and avoid duplication, it contains numerous references providing an entry point into the internal dosimetry literature relevant to this program. The TBM is not intended to act as a policy or procedure statement, but will supplement the information normally found in procedures or policy documents. The internal dosimetry program outlined in this manual is intended to meet the requirements of Federal Rule 10CFR835 for monitoring the workplace and for assessing internal radiation doses to workers.
The RPID Project is implemented at all SNL facilities for activities involving the processing and/or storing of radioactive materials. Reference to SNL throughout this document includes all SNL facilities and activities.
This progress report describes work being done at Sandia National Laboratories (SNL) to assess the localized corrosion performance of container/cask materials used in the interim storage of used nuclear fuel. The work involves both characterization of the potential physical and chemical environment on the surface of the storage canisters and how it might evolve through time, and testing to evaluate performance of the canister materials under anticipated storage conditions.
The Light Initiated High Explosive facility utilized a spray deposited coating of silver acetylide - silver nitrate explosive to impart a mechanical shock into targets of interest. A diagnostic was required to measure the explosive deposition in - situ. An X - ray fluorescence spectrometer was deployed at the facility. A measurement methodology was developed to measure the explosive quantity with sufficient accuracy. Through the use of a tin reference material under the silver based explosive, a field calibration relationship has been developed with a standard deviation of 3.2 % . The effect of the inserted tin material into the experiment configuration has been explored.
Recent advances in nanotechnology have enabled researchers to control individual quantum mechanical objects with unprecedented accuracy, opening the door for both quantum and extreme- scale conventional computation applications. As these devices become more complex, designing for facility of control becomes a daunting and computationally infeasible task. Here, motivated by ideas from compressed sensing, we introduce a protocol for the Compressed Optimization of Device Architectures (CODA). It leads naturally to a metric for benchmarking and optimizing device designs, as well as an automatic device control protocol that reduces the operational complexity required to achieve a particular output. Because this protocol is both experimentally and computationally efficient, it is readily extensible to large systems. For this paper, we demonstrate both the bench- marking and device control protocol components of CODA through examples of realistic simulations of electrostatic quantum dot devices, which are currently being developed experimentally for quantum computation.
A modified version of an indust ry standard wave modeling tool was evaluated, optimized, and utilized to investigate model sensitivity to input parameters a nd wave energy converter ( WEC ) array deployment scenarios. Wave propagation was investigated d ownstream of the WECs to evaluate overall near - and far - field effects of WEC arrays. The sensitivity study illustrate d that wave direction and WEC device type we r e most sensitive to the variation in the model parameters examined in this study . Generally, the changes in wave height we re the primary alteration caused by the presence of a WEC array. Specifically, W EC device type and subsequently their size directly re sult ed in wave height variations; however, it is important to utilize ongoing laboratory studies and future field tests to determine the most appropriate power matrix values for a particular WEC device and configuration in order to improve modeling results .
The performance of the Encell Nickel Iron (NiFe) battery was measured. Tests included capacity, capacity as a function of rate, capacity as a function of temperature, charge retention (28-day), efficiency, accelerated life projection, and water refill evaluation. The goal of this work was to evaluate the general performance of the Encell NiFe battery technology for stationary applications and demonstrate the chemistry's capabilities in extreme conditions. Test results have indicated that the Encell NiFe battery technology can provide power levels up to the 6C discharge rate, ampere-hour efficiency above 70%. In summary, the Encell batteries have met performance metrics established by the manufacturer. Long-term cycle tests are not included in this report. A cycle test at elevated temperature was run, funded by the manufacturer, which Encell uses to predict long-term cycling performance, and which passed their prescribed metrics.
Battery separators based upon lithium thiophosphate (LiPS4) have previously been demonstrated at UC Boulder, but the thickness of the separators was too high to be of practical use in a lithium ion battery. The separators are solid phase, which makes them intrinsically less prone to thermal runaway and thereby improves safety. Results of attempting to develop sputtered thin film layers of this material by starting with targets of pure Li, Li2S, and P2S5 are reported. Sputtering rates and film quality and composition are discussed, along with efforts to use Raman spectroscopy to determine quantitative film composition. The latter is a rate limiting step in the investigation of these films, as they are typically thin and require long times to get to sufficient thickness to be analyzed using traditional methods, whereas Raman is particularly well suited to this analysis, if it can be made quantitative. The final results of the film deposition methods are reported, and a path towards new films is discussed. Finally, it should be noted that this program originally began with one graduate student working on the program, but this student ultimately chose to not continue with a PhD. A second student took over in the middle of the effort, and a new program has been proposed with a significantly altered chemistry to take the program in a new direction.
A three dimensional orthotropic elastic constitutive model with continuum damage and cohesive based fracture is implemented for a general polymer matrix composite lamina. The formulation assumes the possibility of distributed (continuum) damage followed b y localized damage. The current damage activation functions are simply partially interactive quadratic strain criteria . However, the code structure allows for changes in the functions without extraordinary effort. The material model formulation, implementation, characterization and use cases are presented.
A modified version of an indust ry standard wave modeling tool, SNL - SWAN, was used to perform model simulations for hourly initial wave conditio ns measured during the month of October 2009. The model was run with an array of 50 wave energy converters (WECs) and compared with model runs without WECs. Maximum changes in H s were found in the lee of the WEC array along the angles of incident wave dire ction and minimal changes were found along the western side of the model domain due to wave shadowing by land. The largest wave height reductions occurred during observed typhoon conditions and resulted in 14% decreases in H s along the Santa Cruz shoreline . Shoreline reductions in H s were 5% during s outh swell wave conditions and negligible during average monthly wave conditions.
Throughout my HS-STEM internship, I worked on two different projects with a systems analysis group at Sandia National Laboratories in Livermore, California (SNLCA). The first, and primary, project entailed building a conceptual model of health surveillance detection of a bioterror attack. The second project was much smaller in scope and looked at cost tradeoffs between volumetric and surface decontamination after the release of anthrax in a city. Both projects helped me to understand the challenges of planning for a bioterror attack and the importance of preparedness in the public health sector.
Environmental contours describing extreme sea states are generated as the input for numerical or physical model simulation s as a part of the stand ard current practice for designing marine structure s to survive extreme sea states. Such environmental contours are characterized by combinations of significant wave height ( ) and energy period ( ) values calculated for a given recurrence interval using a set of data based on hindcast simulations or buoy observations over a sufficient period of record. The use of the inverse first - order reliability method (IFORM) i s standard design practice for generating environmental contours. In this paper, the traditional appli cation of the IFORM to generating environmental contours representing extreme sea states is described in detail and its merits and drawbacks are assessed. The application of additional methods for analyzing sea state data including the use of principal component analysis (PCA) to create an uncorrelated representation of the data under consideration is proposed. A reexamination of the components of the IFORM application to the problem at hand including the use of new distribution fitting techniques are shown to contribute to the development of more accurate a nd reasonable representations of extreme sea states for use in survivability analysis for marine struc tures. Keywords: In verse FORM, Principal Component Analysis , Environmental Contours, Extreme Sea State Characteri zation, Wave Energy Converters
To help members of the workforce understand what factors contribute to Sandia National Laboratories national security mission, the authors describe the evolution of Sandias core mission and its other mission components. The mission of Sandia first as a division of Los Alamos and later as Sandia Corporation underlies our core nuclear weapon mission of today. Sandias mission changed in 1963 and twice more in the 1970s. This report should help staff and management appreciate the need for mission evolution. A clear definition and communication of a consistent corporate mission statement is still needed.
Lauer, Mark A.; Poirier, David R.; Erdmann, Robert G.; Tewari, Surendra N.; Madison, Jonathan D.
This report covers the modeling of seven directionally solidified samples, five under normal gravitational conditions and two in microgravity. A model is presented to predict macrosegregation during the melting phases of samples solidified under microgravitational conditions. The results of this model are compared against two samples processed in microgravity and good agreement is found. A second model is presented that captures thermosolutal convection during directional solidification. Results for this model are compared across several experiments and quantitative comparisons are made between the model and the experimentally obtained radial macrosegregation profiles with good agreement being found. Changes in cross section were present in some samples and micrographs of these are qualitatively compared with the results of the simulations. It is found that macrosegregation patterns can be affected by changing the mold material.
This report provides a detailed characterization Tri-lab Tantalum (Ta) plate jointly purchased from HCStark Inc. by Sandia, Los Alamos and Lawrence Livermore National Laboratories. Data in this report was compiled from series of material and properties characterization experiments carried out at Sandia (SNL) and Los Alamos (LANL) Laboratories through a leveraged effort funded by the C2 campaign. Results include microstructure characterization detailing the crystallographic texture of the material and an increase in grain size near the end of the rolled plate. Mechanical properties evaluations include, compression cylinder, sub-scale tension specimen, micohardness and instrumented indentation testing. The plate was found to have vastly superior uniformity when compare with previously characterized wrought Ta material. Small but measurable variations in microstructure and properties were noted at the end, and at the top and bottom edges of the plate.
The Used Fuel Disposition Campaign (UFDC) of the U.S. Department of Energy (DOE) Office of Nuclear Energy (NE) is conducting research and development (R&D) on generic deep geologic disposal systems (i.e., repositories) for high-activity nuclear wastes (i.e., used nuclear fuel (UNF) and high-level radioactive waste (HLW)) that exist today or that could be generated in future fuel cycles. This report describes specific activities in FY2014 toward the development of an enhanced generic disposal system modeling and analysis capability that utilizes high performance computing (HPC) environments to simulate important multi-physics phenomena and couplings associated with the potential behavior of a geologic repository for UNF and HLW.
The cycling of high-capacity electrode materials for lithium-ion batteries results in significant volumetric expansion and contraction, and this leads to mechanical failure of the electrodes. To increase battery performance and reliability, there is a drive towards the use of nanostructured electrode materials and nanoscale surface coatings. As a part of the Visiting Faculty Program (VFP) last summer, we examined the ability of aluminum oxide and gold film surface coatings to improve the mechanical and cycling properties of vapor-deposited aluminum films in lithium-ion batteries. Nanoscale gold coatings resulted in significantly improved cycling behavior for the thinnest aluminum films whereas aluminum oxide coatings did not improve the cycling behavior of the aluminum films. This summer we performed a similar investigation on vapor-deposited germanium, which has an even higher theoretical capacity per unit mass than aluminum. Because the mechanism of lithium-alloying is different for each electrode material, we expected the effects of coating the germanium surface with aluminum oxide or gold to differ significantly from previous observations. Indeed, we found that gold coatings gave only small or negligible improvements in cycling behavior of germanium films, but aluminum oxide (Al2O3) coatings gave significant improvements in cycling over the range of film thicknesses tested.
A series of field experiments were undertaken to evaluate the performance of the one dimensional time encoded imaging system. The significant detection of a Cf252 fission radiation source was demonstrated at a stand-off of 100 meters. Extrapolations to different quantities of plutonium equivalent at different distances are made. Hardware modifications to the system for follow on work are suggested.
A code for generating MCNP material cards (MatMCNP) has been written and verified for naturally occurring, stable isotopes. The program allows for material specification as either atomic or weight percent (fractions). MatMCNP also permits the specification of enriched lithium, boron, and/or uranium. In addition to producing the material cards for MCNP, the code calculates the atomic (or number) density in atoms/barn-cm as well as the multiplier that should be used to convert neutron and gamma fluences into dose in the material specified.