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Ductility Characterization of U-6Nb and Ta-W Alloys

Description: We have previously evaluated the ductility behaviors of U-6Nb and pure Ta. One important observation was that both alloys have very stable necking ductility independent of test conditions. In contrast, uniform ductility varied significantly depending upon strain rates and temperatures. In general, higher strain rate and lower temperature reduce the uniform ductility. Using literature data, we have developed two dynamic ductility models to predict the ductility behaviors of pure-Ta and water-quenched U-6Nb respectively under extreme conditions. In this study we further evaluate the aging effect on U-6Nb and the W-addition effect on Ta. For U-6Nb, the objective is to determine whether or not the ductility degradation by low-temperature aging mostly measured in quasi-static condition can still be observed under dynamic loading (high strain rate) condition. For Ta-W alloys, the focus is to identify the key control parameter so that the optimal condition of high-strength/high-ductility of Ta-10W can be achieved for certain defense-related applications.
Date: September 15, 2006
Creator: Sun, T & Cervantes, O
Partner: UNT Libraries Government Documents Department

The US nuclear weapon infrastructure and a stable global nuclear weapon regime

Description: US nuclear weapons capabilities -- extant force structure and nuclear weapons infrastructure as well as declared policy -- influence other nations' nuclear weapons postures, at least to some extent. This influence can be desirable or undesirable, and is, of course, a mixture of both. How strong the influence is, and its nature, are complicated, controversial, and -- in our view -- not well understood but often overstated. Divergent views about this influence and how it might shape the future global nuclear weapons regime seem to us to be the most serious impediment to reaching a national consensus on US weapons policy, force structure and supporting infrastructure. We believe that a paradigm shift to capability-based deterrence and dissuasion is not only consistent with the realities of the world and how it has changed, but also a desirable way for nuclear weapon postures and infrastructures to evolve. The US and other nuclear states could not get to zero nor even reduce nuclear arms and the nuclear profile much further without learning to manage latent capability. This paper has defined three principles for designing NW infrastructure both at the 'next plateau' and 'near zero.' The US can be a leader in reducing weapons and infrastructure and in creating an international regime in which capability gradually substitutes for weapons in being and is transparent. The current 'strategy' of not having policy or a Congressionally-approved plan for transforming the weapons complex is not leadership. If we can conform the US infrastructure to the next plateau and architect it in such a way that it is aligned with further arms reductions, it will have these benefits: The extant stockpile can be reduced in size, while the smaller stockpile still deters attack on the US and Allies. The capabilities of the infrastructure will dissuade emergence of new ...
Date: January 1, 2009
Creator: Immele, John D & Wagner, Richard L
Partner: UNT Libraries Government Documents Department

Reliability Degradation Due to Stockpile Aging

Description: The objective of this reseach is the investigation of alternative methods for characterizing the reliability of systems with time dependent failure modes associated with stockpile aging. Reference to 'reliability degradation' has, unfortunately, come to be associated with all types of aging analyes: both deterministic and stochastic. In this research, in keeping with the true theoretical definition, reliability is defined as a probabilistic description of system performance as a funtion of time. Traditional reliability methods used to characterize stockpile reliability depend on the collection of a large number of samples or observations. Clearly, after the experiments have been performed and the data has been collected, critical performance problems can be identified. A Major goal of this research is to identify existing methods and/or develop new mathematical techniques and computer analysis tools to anticipate stockpile problems before they become critical issues. One of the most popular methods for characterizing the reliability of components, particularly electronic components, assumes that failures occur in a completely random fashion, i.e. uniformly across time. This method is based primarily on the use of constant failure rates for the various elements that constitute the weapon system, i.e. the systems do not degrade while in storage. Experience has shown that predictions based upon this approach should be regarded with great skepticism since the relationship between the life predicted and the observed life has been difficult to validate. In addition to this fundamental problem, the approach does not recognize that there are time dependent material properties and variations associated with the manufacturing process and the operational environment. To appreciate the uncertainties in predicting system reliability a number of alternative methods are explored in this report. All of the methods are very different from those currently used to assess stockpile reliability, but have been used extensively in various forms outside Sandia ...
Date: April 1, 1999
Creator: Robinson, David G.
Partner: UNT Libraries Government Documents Department

EFFECT OF TRITIUM AND DECAY HELIUM ON WELDMENT FRACTURE TOUGHNESS

Description: The fracture toughness data collected in this study are needed to assess the long-term effects of tritium and its decay product on tritium reservoirs. The results show that tritium and decay helium have negative effects on the fracture toughness properties of stainless steel and its weldments. The data and report from this study has been included in a material property database for use in tritium reservoir modeling efforts like the Technology Investment Program ''Lifecycle Engineering for Tritium Reservoirs''. A number of conclusions can be drawn from the data: (1) For unexposed Type 304L stainless steel, the fracture toughness of weldments was two to three times higher than the base metal toughness. (2) Tritium exposure lowered the fracture toughness properties of both base metals and weldments. This was characterized by lower J{sub Q} values and lower J-da curves. (3) Tritium-exposed-and-aged base metals and weldments had lower fracture toughness values than unexposed ones but still retained good toughness properties.
Date: September 26, 2006
Creator: Morgan, M; Scott West, S & Michael Tosten, M
Partner: UNT Libraries Government Documents Department

SELF-ORGANIZED CRITICALITY AND CELLULAR AUTOMATA

Description: Cellular automata provide a fascinating class of dynamical systems based on very simple rules of evolution yet capable of displaying highly complex behavior. These include simplified models for many phenomena seen in nature. Among other things, they provide insight into self-organized criticality, wherein dissipative systems naturally drive themselves to a critical state with important phenomena occurring over a wide range of length and the scales. This article begins with an overview of self-organized criticality. This is followed by a discussion of a few examples of simple cellular automaton systems, some of which may exhibit critical behavior. Finally, some of the fascinating exact mathematical properties of the Bak-Tang-Wiesenfeld sand-pile model [1] are discussed.
Date: January 1, 2007
Creator: CREUTZ,M.
Partner: UNT Libraries Government Documents Department

Magnetic Resonance Based Diagnostics for Polymer Production and Surveillance

Description: In an effort to develop a magnetic resonance based diagnostic tool to be used for polymer production and surveillance, we have investigated the use of magnetic resonance imaging (MRI) and unilateral relaxometry. MRI provides a spatial map of the polymer, which can be correlated to the structure heterogeneity. Though highly detailed information can be obtained with MRI, the high equipment cost and expertise required to operate the system makes it a poor choice for a production setting. Unilateral relaxometry via the NMR MOUSE provides rapid, inexpensive polymer screening, useful in the development in new polymer parts or to identify potentially defective components. The NMR ProFiler (originally called the NMR MOUSE) was procured by Kansas City originally for production support of the W80 LEP with future applications as a surveillance diagnostic. A robotic autosampler has been designed allowing the detection of several components without the need for any human interaction. A summary of the qualification experiments and results to date from the ProFiler and the robotic unit will be presented.
Date: September 27, 2006
Creator: Chinn, S; Herberg, J; Gjersing, E; Cook, A; Sawvel, A M; Maxwell, R et al.
Partner: UNT Libraries Government Documents Department

2007 Inventory of Radiochemistry Detector Elements and Compounds

Description: Since the last report, there have been no material changes in the detector element inventories in buildings 151 and 332 at LLNL. Stable element inventories in building 151 have remained stable since the inventory in September 2005. For the first time in many years, Stockpile Radiochemistry personnel viewed radioactive tracer materials that reside in building 332. A list of LLNL tracers and locations are available under separate cover. Despite the recent NNSA agreement to retain 2.8 kg of {sup 233}U for programmatic purposes, we have yet to identify a location that is appropriate and will accept the material. A recent visit to the Oak Ridge National Laboratory (ORNL) in September 2006 revealed nearly 190 kg of material with very high {sup 233}U content scheduled for down-blending in various chemical and isotopic forms. The chemical form, isotopic and chemical purities of this material were such that roughly 150 kg of the material was of comparable composition to the desired tracer package material and would be acceptable for use in an underground test, should the US even conduct such a test. Efforts continue to remove 2.8 kg of material from the down-blend cue and reserve it for the Test Readiness mission.
Date: April 5, 2007
Creator: Kenneally, J & Roberts, K
Partner: UNT Libraries Government Documents Department

The Deformation-DIA: A Novel Apparatus for Measuring the Strength of Materials at High Strain to Pressures at Elevated Temperature

Description: The primary focus of this 3-year project was to develop and put to use an instrument to test experimentally the effect of pressure on body centered cubic (BCC) metals and other materials of interest to the Stockpile Stewardship program. Well-resolved materials testing requires measurements of load and deformation rate be measured at separable conditions of temperature, pressure, and plastic strain. The new apparatus at the heart of this work, the Deformation-DIA (D-DIA), began the project as a design concept. Its principal feature would be the capability to extend the conditions for such controlled materials testing from the current pressure limit of about 3 to almost 15 GPa, a factor of 5 increase. Once constructed and successfully tested, the plan of the project was to deform samples of BCC metals at arbitrary temperature and high pressures in order to provide preliminary measurements of strength and to prove its worth to the Stockpile Stewardship program. The project has been a stunning success. Progress toward demonstrating the worth of the D-DIA as a workhorse instrument for materials strength measurement at high pressure was given a huge boost by the fact that the machine itself functioned flawlessly from the very start, allowing the investigators to focus on measurement quality rather than technical operational issues. By the end of the project, we had deformed several samples of polycrystalline molybdenum (Mo) and tantalum (Ta) under very precisely controlled conditions, and for the Ta, had produced the first rudimentary measurements of strength to pressures of 8 GPa.
Date: March 10, 2004
Creator: Durham, W
Partner: UNT Libraries Government Documents Department

Questions and Answers Regarding Actions to Take When Ending Shelter-in-Place

Description: Shelter-in-place has found increasing acceptance as an effective protective action option for communities participating in the Chemical Stockpile Emergency Preparedness Program. Studies have confirmed that it can provide optimum protection under certain accident conditions. However, emergency managers and planners, as well as the public, continue to be troubled by the need to end sheltering when the plume has passed in order to avoid sustained exposure to the small amount of agent that has penetrated the shelter. One of the concerns posed by this necessity is uncertainty regarding what hazards will then be faced in the environment outside the shelter and what actions can be taken to avoid those hazards. This report attempts to address those uncertainties. It recognizes that there is an extremely low probability that the environment outside the shelter will be contaminated with chemical agent residue. However, as people comply with an official recommendation to leave their shelters, they probably can't be certain that the environment is free from contamination. Therefore, this report identifies and explains specific and simple actions they can take to avoid the possibility of exposure to chemical agent hazards outside their shelters. It addresses such issues as the actions people should take upon ending shelter-in-place, what clothing they should wear, how they should handle animals, and what they should do about food in their homes and produce in their gardens.
Date: December 30, 2003
Creator: Shumpert, B.
Partner: UNT Libraries Government Documents Department

APPLICATION OF RISK MANAGEMENT PRACTICES TO NNSA TRITIUM READINESS SUBPROGRAM

Description: The National Nuclear Security Administration (NNSA), Office of Stockpile Technology (NNSA/NA-123) chartered a risk assessment of the Tritium Readiness (TR) Subprogram to identify risks and to develop handling strategies with specific action items that could be scheduled and tracked to completion in order to minimize program failures. This assessment was performed by a team of subject matter experts (SMEs) comprised of representatives from various organizations participating in the TR Subprogram. The process was coordinated by Savannah River Site, Systems Engineering (SRS/SE) with support from Subprogram Team. The Risk Management Process steps performed during this risk assessment were: Planning, Identification, Grading, Handling, and Impact Determination. All of the information captured during the risk assessment was recorded in a database. The team provided estimates for the cost and schedule impacts of implementing the recommended handling strategies and facilitated the risk based cost contingency analysis. The application of the Risk Management Practices to the NNSA Tritium Readiness Subprogram resulted in: (1) The quarterly review and update of the Risk Management Database to include an evaluation of all existing risks and the identification/evaluation of any potential new risks. (2) The risk status and handling strategy action item tracking mechanism that has visibility and buy-in throughout the Tritium Readiness Subprogram to ensure that approved actions are completed as scheduled and that risk reduction is being achieved. (3) The generation of a risk-based cost contingency estimate that may be used by the Tritium Readiness Subprogram Manager in establishing future year program budgets.
Date: January 31, 2007
Creator: Shete, S & Srini Venkatesh, S
Partner: UNT Libraries Government Documents Department

Towards Understanding the Mechanism of PETN Coarsening

Description: The long-term goal is to determine the mechanism of PETN crystallization and coarsening at the solid-vapor interface and to quantify the thermodynamic and kinetic parameters that control those processes. We achieve this goal by investigating the surface evolution of synthetic PETN single crystals using in situ atomic force microscopy (AFM) at various temperatures.
Date: March 23, 2005
Creator: Qiu, R; Overturf, G; Gee, R; Burnham, A; Weeks, B & De Yoreo, J
Partner: UNT Libraries Government Documents Department

Surveillance metrics sensitivity study.

Description: In September of 2009, a Tri-Lab team was formed to develop a set of metrics relating to the NNSA nuclear weapon surveillance program. The purpose of the metrics was to develop a more quantitative and/or qualitative metric(s) describing the results of realized or non-realized surveillance activities on our confidence in reporting reliability and assessing the stockpile. As a part of this effort, a statistical sub-team investigated various techniques and developed a complementary set of statistical metrics that could serve as a foundation for characterizing aspects of meeting the surveillance program objectives. The metrics are a combination of tolerance limit calculations and power calculations, intending to answer level-of-confidence type questions with respect to the ability to detect certain undesirable behaviors (catastrophic defects, margin insufficiency defects, and deviations from a model). Note that the metrics are not intended to gauge product performance but instead the adequacy of surveillance. This report gives a short description of four metrics types that were explored and the results of a sensitivity study conducted to investigate their behavior for various inputs. The results of the sensitivity study can be used to set the risk parameters that specify the level of stockpile problem that the surveillance program should be addressing.
Date: September 1, 2011
Creator: Hamada, Michael S. (Los Alamos National Laboratory); Bierbaum, Rene Lynn & Robertson, Alix A. (Lawrence Livermore Laboratory)
Partner: UNT Libraries Government Documents Department

The Reutter/Wade Toxicity Report and CSEPP Civilian Emergency Planning

Description: The Reutter/Wade analysis (Reutter and Wade 1994) was undertaken to improve the technical basis for assessing battlefield casualties from deployment of chemical weapons containing nerve and sulfur mustard agent payloads. The analysis sought to utilize available data and modern, accepted, toxicological methods to develop agent-specific casualty estimators for U.S. military forces. The authors also estimated qualitative confidence levels for each estimator based on the quality and quantity of the data. For percutaneous and inhalation vapor exposures, the report estimated cumulative exposures necessary to achieve lethal (LCt{sub 50}), severe (ED{sub 50}), threshold (percutaneous vapor only, ECt{sub 50}), or mild (nasal vapor, ECt{sub 50}) effects. For percutaneous liquid exposures, the report estimated lethal (LD{sub 50}) and severe (ED{sub 50}) doses. The vapor exposures necessary to achieve mild ocular effects were also estimated. This report examines potential implications of the Reutter/Wade study for off-site or civilian emergency planning in the Chemical Stockpile Emergency Preparedness Program (CSEPP) and summarizes principal findings of the Reutter/Wade report, the National Academy review of Reutter/Wade, and the Institute for Defense Analysis (IDA) expert panel assessment of Reutter/Wade casualty estimators. This report also identifies how estimates of human health effects are used in CSEPP, organized by functional planning topics. Finally CSEPP casualty estimators are considered in light of the Reutter/Wade work.
Date: August 4, 1999
Creator: Sorensen, J.H.
Partner: UNT Libraries Government Documents Department

Level-2 Milestone 3244: Deploy Dawn ID Machine for Initial Science Runs

Description: This report documents the delivery, installation, integration, testing, and acceptance of the Dawn system, ASC L2 milestone 3244: Deploy Dawn ID Machine for Initial Science Runs, due September 30, 2009. The full text of the milestone is included in Attachment 1. The description of the milestone is: This milestone will be a result of work started three years ago with the planning for a multi-petaFLOPS UQ-focused platform (Sequoia) and will be satisfied when a smaller ID version of the final system is delivered, installed, integrated, tested, accepted, and deployed at LLNL for initial science runs in support of SSP mission. The deliverable for this milestone will be a LA petascale computing system (named Dawn) usable for code development and scaling necessary to ensure effective use of a final Sequoia platform (expected in 2011-2012), and for urgent SSP program needs. Allocation and scheduling of Dawn as an LA system will likely be performed informally, similar to what has been used for BlueGene/L. However, provision will be made to allow for dedicated access times for application scaling studies across the entire Dawn resource. The milestone was completed on April 1, 2009, when science runs began running on the Dawn system. The following sections describe the Dawn system architecture, current status, installation and integration time line, and testing and acceptance process. A project plan is included as Attachment 2. Attachment 3 is a letter certifying the handoff of the system to a nuclear weapons stockpile customer. Attachment 4 presents the results of science runs completed on the system.
Date: September 21, 2009
Creator: Fox, D
Partner: UNT Libraries Government Documents Department

Science and Technology Review July/August 2010

Description: This issue has the following articles: (1) Deterrence with a Minimum Nuclear Stockpile - Commentary by Bruce T. Goodwin; (2) Enhancing Confidence in the Nation's Nuclear Stockpile - Livermore experts are participating in a national effort aimed at predicting how nuclear weapon materials and systems will likely change over time; (3) Narrowing Uncertainties - For climate modeling and many other fields, understanding uncertainty, or margin of error, is critical; (4) Insight into a Deadly Disease - Laboratory experiments reveal the pathogenesis of tularemia in host cells, bringing scientists closer to developing a vaccine for this debilitating disease. (5) Return to Rongelap - On the Rongelap Atoll, Livermore scientists are working to minimize radiological exposure for natives now living on or wishing to return to the islands.
Date: May 27, 2010
Creator: Blobaum, K M
Partner: UNT Libraries Government Documents Department

Science and technology in the stockpile stewardship program, S & TR reprints

Description: This document reports on these topics: Computer Simulations in Support of National Security; Enhanced Surveillance of Aging Weapons; A New Precision Cutting Tool: The Femtosecond Laser; Superlasers as a Tool of Stockpile Stewardship; Nova Laser Experiments and Stockpile Stewardship; Transforming Explosive Art into Science; Better Flash Radiography Using the FXR; Preserving Nuclear Weapons Information; Site 300Õs New Contained Firing Facility; The Linear Electric Motor: Instability at 1,000 gÕs; A Powerful New Tool to Detect Clandestine Nuclear Tests; High Explosives in Stockpile Surveillance Indicate Constancy; Addressing a Cold War Legacy with a New Way to Produce TATB; JumpinÕ Jupiter! Metallic Hydrogen; Keeping the Nuclear Stockpile Safe, Secure, and Reliable; The Multibeam FabryÐPerot Velocimeter: Efficient Measurements of High Velocities; Theory and Modeling in Material Science; The Diamond Anvil Cell; Gamma-Ray Imaging Spectrometry; X-Ray Lasers and High-Density Plasma
Date: April 8, 1998
Creator: Storm, E
Partner: UNT Libraries Government Documents Department

Infrastructure for distributed enterprise simulation

Description: Traditional discrete-event simulations employ an inherently sequential algorithm and are run on a single computer. However, the demands of many real-world problems exceed the capabilities of sequential simulation systems. Often the capacity of a computer`s primary memory limits the size of the models that can be handled, and in some cases parallel execution on multiple processors could significantly reduce the simulation time. This paper describes the development of an Infrastructure for Distributed Enterprise Simulation (IDES) - a large-scale portable parallel simulation framework developed to support Sandia National Laboratories` mission in stockpile stewardship. IDES is based on the Breathing-Time-Buckets synchronization protocol, and maps a message-based model of distributed computing onto an object-oriented programming model. IDES is portable across heterogeneous computing architectures, including single-processor systems, networks of workstations and multi-processor computers with shared or distributed memory. The system provides a simple and sufficient application programming interface that can be used by scientists to quickly model large-scale, complex enterprise systems. In the background and without involving the user, IDES is capable of making dynamic use of idle processing power available throughout the enterprise network. 16 refs., 14 figs.
Date: January 1, 1998
Creator: Johnson, M.M.; Yoshimura, A.S. & Goldsby, M.E.
Partner: UNT Libraries Government Documents Department

Enhanced Gas Analysis for Diagnostics and Surveillance (EGADS): Contamination-free sampling and analysis

Description: Providing uncontaminated weapon internal atmosphere samples and measuring their dew points is of paramount importance for enhanced surveillance and accelerated aging. The authors are developing and integrating four types of gas sampling systems for use throughout the weapons complex. They are utilizing tools to extract time/age information from the gas analysis of weapon internal atmospheres.
Date: October 1, 1997
Creator: Maestas, L.M.; Guilinger, T.R. & Kelly, M.J.
Partner: UNT Libraries Government Documents Department

Quality prediction and mistake proofing: An LDRD final report

Description: Sandia National Laboratories is responsible for assuring that the US nuclear deterrent remains credible and that the one in a billion disaster of unintended nuclear detonation never occurs. Letting mistake-generated defects into the stockpile would undermine its mission. The current era of shrinking stockpiles is shrinking Sandia`s opportunities to discover and correct mistakes and fine tune processes over long production runs. In response, Sandia has chosen to develop and use a science-based, life cycle systems engineering practices that, in part, require understanding the design to manufacturing issues in enough detail to tune processes and eliminate mistakes before ever making a part. Defect prevention is a key area of concern that currently lacks sufficient theoretical understanding. This report is the result of a scoping study in the application of best-practice quality techniques that could address Sandia`s stockpile mission. The study provides detail on sources and control of mistakes, poka-yoke or mistake-proofing techniques, the Toyota Production system, and design theory in relation to manufacturing quality prediction. Scoping experiments are described and areas for future research are identified.
Date: March 1, 1998
Creator: McDonald, M.J.
Partner: UNT Libraries Government Documents Department

Low energy demonstration accelerator technical area 53

Description: As part of the Department of Energy`s (DOE) need to maintain the capability of producing tritium in support of its historic and near-term stewardship of the nation`s nuclear weapons stockpile, the agency has recently completed a Programmatic Environmental Impact Statement for Tritium Supply and Recycling. The resulting Record of Decision (ROD) determined that over the next three years the DOE would follow a dual-track acquisition strategy that assures tritium production for the nuclear weapon stockpile in a rapid, cost effective, and safe manner. Under this strategy the DOE will further investigate and compare two options for producing tritium: (1) purchase of an existing commercial light-water reactor or irradiation services with an option to purchase the reactor for conversion to a defense facility; and (2) design, build, and test critical components of a system for accelerator production of tritium (APT). The final decision to select the primary production option will be made by the Secretary of Energy in the October 1998 time frame. The alternative not chosen as the primary production method, if feasible, would be developed as a back-up tritium supply source. This Environmental Assessment (EA) analyzes the potential environmental effects that would be expected to occur if the DOE were to design, build, and test critical prototypical components of the accelerator system for tritium production, specifically the front-end low-energy section of the accelerator, at Los Alamos National Laboratory. The Low Energy Demonstration Accelerator (LEDA) would be incrementally developed and tested in five separate stages over the next seven years. The following issues were evaluated for the proposed action: utility demands, air, human health, environmental restoration, waste management, transportation, water, threatened and endangered species, wetlands, cultural resources, and environmental justice.
Date: April 1, 1996
Partner: UNT Libraries Government Documents Department

Reaching Part Per Trillion Clean-Up Criteria for Mercury in Water

Description: In the last couple of years, emphasis on environmental mercury contamination and elimination of mercury use has increased. The U.S. Department of Energy has for many decades maintained a stockpile of elemental mercury for operations and, as a consequence of its routine use, spills have occurred. These historical spills have resulted in some contamination of water streams and soils. In this work we examine a newly developed technique for removal of mercury from contaminated groundwater. In this application the mercury concentration was approximately 2.3 parts per billion and the treatment criterion was 200 parts per trillion. Several forms of mercury species contributed to the contamination. The treatment technique developed for this water was to convert all forms of mercury, through a series of fast chemical reactions, to elemental mercury, which was air-stripped from the water. This paper presents preliminary laboratory work on the method.
Date: February 24, 2003
Creator: Klasson, K. T.; Kosny, K.; Drescher, S. R.; Southworth, G. R. & Hensley, J. F.
Partner: UNT Libraries Government Documents Department