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Compatibility/Stability Issues in the Use of Nitride Kernels in LWR TRISO Fuel (open access)

Compatibility/Stability Issues in the Use of Nitride Kernels in LWR TRISO Fuel

The stability of the SiC layer in the presence of free nitrogen will be dependent upon the operating temperatures and resulting nitrogen pressures whether it is at High Temperature Gas-Cooled Reactor (HTGR) temperatures of 1000-1400 C (coolant design dependent) or LWR temperatures that range from 500-700 C. Although nitrogen released in fissioning will form fission product nitrides, there will remain an overpressure of nitrogen of some magnitude. The nitrogen can be speculated to transport through the inner pyrolytic carbon layer and contact the SiC layer. The SiC layer may be envisioned to fail due to resulting nitridation at the elevated temperatures. However, it is believed that these issues are particularly avoided in the LWR application. Lower temperatures will result in significantly lower nitrogen pressures. Lower temperatures will also substantially reduce nitrogen diffusion rates through the layers and nitriding kinetics. Kinetics calculations were performed using an expression for nitriding silicon. In order to further address these concerns, experiments were run with surrogate fuel particles under simulated operating conditions to determine the resulting phase formation at 700 and 1400 C.
Date: February 1, 2012
Creator: Armstrong, Beth L & Besmann, Theodore M
System: The UNT Digital Library
High Performance Computing Facility Operational Assessment, CY 2011 Oak Ridge Leadership Computing Facility (open access)

High Performance Computing Facility Operational Assessment, CY 2011 Oak Ridge Leadership Computing Facility

Oak Ridge National Laboratory's Leadership Computing Facility (OLCF) continues to deliver the most powerful resources in the U.S. for open science. At 2.33 petaflops peak performance, the Cray XT Jaguar delivered more than 1.4 billion core hours in calendar year (CY) 2011 to researchers around the world for computational simulations relevant to national and energy security; advancing the frontiers of knowledge in physical sciences and areas of biological, medical, environmental, and computer sciences; and providing world-class research facilities for the nation's science enterprise. Users reported more than 670 publications this year arising from their use of OLCF resources. Of these we report the 300 in this review that are consistent with guidance provided. Scientific achievements by OLCF users cut across all range scales from atomic to molecular to large-scale structures. At the atomic scale, researchers discovered that the anomalously long half-life of Carbon-14 can be explained by calculating, for the first time, the very complex three-body interactions between all the neutrons and protons in the nucleus. At the molecular scale, researchers combined experimental results from LBL's light source and simulations on Jaguar to discover how DNA replication continues past a damaged site so a mutation can be repaired later. Other …
Date: February 1, 2012
Creator: Baker, Ann E; Barker, Ashley D; Bland, Arthur S Buddy; Boudwin, Kathlyn J.; Hack, James J; Kendall, Ricky A et al.
System: The UNT Digital Library
High Performance Computing Facility Operational Assessment, 2012 Oak Ridge Leadership Computing Facility (open access)

High Performance Computing Facility Operational Assessment, 2012 Oak Ridge Leadership Computing Facility

None
Date: February 1, 2012
Creator: Barker, Ashley D; Bernholdt, David E; Bland, Arthur S Buddy; Hack, James J; Hudson, Douglas L; Messer, Bronson et al.
System: The UNT Digital Library
Analytic approximate radiation effects due to Bremsstrahlung (open access)

Analytic approximate radiation effects due to Bremsstrahlung

The purpose of this note is to provide analytic approximate expressions that can provide quick estimates of the various effects of the Bremsstrahlung radiation produced relatively low energy electrons, such as the dumping of the beam into the beam stop at the ERL or field emission in superconducting cavities. The purpose of this work is not to replace a dependable calculation or, better yet, a measurement under real conditions, but to provide a quick but approximate estimate for guidance purposes only. These effects include dose to personnel, ozone generation in the air volume exposed to the radiation, hydrogen generation in the beam dump water cooling system and radiation damage to near-by magnets. These expressions can be used for other purposes, but one should note that the electron beam energy range is limited. In these calculations the good range is from about 0.5 MeV to 10 MeV. To help in the application of this note, calculations are presented as a worked out example for the beam dump of the R&D Energy Recovery Linac.
Date: February 1, 2012
Creator: Ben-Zvi, Ilan
System: The UNT Digital Library
ITER TCWS Conceptual Design Chit Resolution Report (open access)

ITER TCWS Conceptual Design Chit Resolution Report

Design Chits resulted from the External Conceptual Design Review (CDR) held at Cadarache on July 21-23, 2009 (Reference [5.1.3]). Those Chits were categorized into 3 categories in accordance with the following rules: Category 1 - Chits to be resolved before proceeding with preliminary design; Category 2 - Chits to be resolved during preliminary design; and Category 3 - Chits already resolved or covered by higher category Chits such that no further action is required. Prior to the preliminary design, all the category 1 chits were resolved and the category chit 1 resolution report was approved (Reference [5.1.4]). However, as the design has been evolving, one of the category 1 chits needs to be re-addressed. The purpose of this report is to present the resolutions to one CDR Category 1 Chit (Cat 1 Chit No.5) and twenty-three CDR Category 2 Chits. The Category 2 Chit resolutions presented are listed in order from item number one to item number twenty-three.
Date: February 1, 2012
Creator: Berry, Jan
System: The UNT Digital Library
Framework for Adaptable Operating and Runtime Systems: Final Project Report (open access)

Framework for Adaptable Operating and Runtime Systems: Final Project Report

In this grant, we examined a wide range of techniques for constructing high-performance con#12;gurable system software for HPC systems and its application to DOE-relevant problems. Overall, research and development on this project focused in three specifc areas: (1) software frameworks for constructing and deploying con#12;gurable system software, (2) applcation of these frameworks to HPC-oriented adaptable networking software, (3) performance analysis of HPC system software to understand opportunities for performance optimization.
Date: February 1, 2012
Creator: Bridges, Patrick G.
System: The UNT Digital Library
Grid Modeling for the SunShot Vision Study (open access)

Grid Modeling for the SunShot Vision Study

This document describes the use of production cost modeling in the SunShot Vision study, including methods used to create the SunShot Vision scenarios, their implementation in the Gridview model, and assumptions regarding transmission system and operation of each generator type. It also describes challenges and limitations of modeling solar generation technologies in production cost models, and suggests methods for improving their representation in current models.
Date: February 1, 2012
Creator: Brinkman, G.; Denholm, P.; Drury, E.; Ela, E.; Mai, T.; Margolis, R. et al.
System: The UNT Digital Library
Photoelectronic characterization of heterointerfaces. (open access)

Photoelectronic characterization of heterointerfaces.

In many devices such as solar cells, light emitting diodes, transistors, etc., the performance relies on the electronic structure at interfaces between materials within the device. The objective of this work was to perform robust characterization of hybrid (organic/inorganic) interfaces by tailoring the interfacial region for photoelectron spectroscopy. Self-assembled monolayers (SAM) were utilized to induce dipoles of various magnitudes at the interface. Additionally, SAMs of molecules with varying dipolar characteristics were mixed into spatially organized structures to systematically vary the apparent work function. Polymer thin films were characterized by depositing films of varying thicknesses on numerous substrates with and without interfacial modifications. Hard X-ray photoelectron spectroscopy (HAXPES) was performed to evaluate a buried interface between indium tin oxide (ITO), treated under various conditions, and poly(3-hexylthiophene) (P3HT). Conducting polymer films were found to be sufficiently conducting such that no significant charge redistribution in the polymer films was observed. Consequently, a further departure from uniform substrates was taken whereby electrically disconnected regions of the substrate presented ideally insulating interfacial contacts. In order to accomplish this novel strategy, interdigitated electrodes were used as the substrate. Conducting fingers of one half of the electrodes were electrically grounded while the other set of electrodes were …
Date: February 1, 2012
Creator: Brumbach, Michael Todd
System: The UNT Digital Library
Sandia National Laboratories, California Chemical Management Program annual report. (open access)

Sandia National Laboratories, California Chemical Management Program annual report.

The annual program report provides detailed information about all aspects of the Sandia National Laboratories, California (SNL/CA) Chemical Management Program. It functions as supporting documentation to the SNL/CA Environmental Management System Program Manual. This program annual report describes the activities undertaken during the calender past year, and activities planned in future years to implement the Chemical Management Program, one of six programs that supports environmental management at SNL/CA. SNL/CA is responsible for tracking chemicals (chemical and biological materials), providing Material Safety Data Sheets (MSDS) and for regulatory compliance reporting according to a variety of chemical regulations. The principal regulations for chemical tracking are the Emergency Planning Community Right-to-Know Act (EPCRA) and the California Right-to-Know regulations. The regulations, the Hazard Communication/Lab Standard of the Occupational Safety and Health Administration (OSHA) are also key to the CM Program. The CM Program is also responsible for supporting chemical safety and information requirements for a variety of Integrated Enabling Services (IMS) programs primarily the Industrial Hygiene, Waste Management, Fire Protection, Air Quality, Emergency Management, Environmental Monitoring and Pollution Prevention programs. The principal program tool is the Chemical Information System (CIS). The system contains two key elements: the MSDS library and the chemical container-tracking database …
Date: February 1, 2012
Creator: Brynildson, Mark E.
System: The UNT Digital Library
Strategy Guideline: HVAC Equipment Sizing (open access)

Strategy Guideline: HVAC Equipment Sizing

The heating, ventilation, and air conditioning (HVAC) system is arguably the most complex system installed in a house and is a substantial component of the total house energy use. A right-sized HVAC system will provide the desired occupant comfort and will run efficiently. This Strategy Guideline discusses the information needed to initially select the equipment for a properly designed HVAC system. Right-sizing of an HVAC system involves the selection of equipment and the design of the air distribution system to meet the accurate predicted heating and cooling loads of the house. Right-sizing the HVAC system begins with an accurate understanding of the heating and cooling loads on a space; however, a full HVAC design involves more than just the load estimate calculation - the load calculation is the first step of the iterative HVAC design procedure. This guide describes the equipment selection of a split system air conditioner and furnace for an example house in Chicago, IL as well as a heat pump system for an example house in Orlando, Florida. The required heating and cooling load information for the two example houses was developed in the Department of Energy Building America Strategy Guideline: Accurate Heating and Cooling Load Calculations.
Date: February 1, 2012
Creator: Burdick, A.
System: The UNT Digital Library
DESCRIPTION OF THE TRITIUM-PRODUCING BURNABLE ABSORBER ROD FOR THE COMMERCIAL LIGHT WATER REACTOR TTQP-1-015 Rev 19 (open access)

DESCRIPTION OF THE TRITIUM-PRODUCING BURNABLE ABSORBER ROD FOR THE COMMERCIAL LIGHT WATER REACTOR TTQP-1-015 Rev 19

Tritium-producing burnable absorber rods (TPBARs) used in the U.S. Department of Energy’s Tritium Readiness Program are designed to produce tritium when placed in a Westinghouse or Framatome 17x17 fuel assembly and irradiated in a pressurized water reactor (PWR). This document provides an unclassified description of the current design baseline for the TPBARs. This design baseline is currently valid only for Watts Bar reactor production cores. A description of the Lead Use TPBARs will not be covered in the text of the document, but the applicable drawings, specifications and test plan will be included in the appropriate appendices.
Date: February 1, 2012
Creator: Burns, Kimberly A.; Love, Edward F. & Thornhill, Cheryl K.
System: The UNT Digital Library
Assessment of Strike of Adult Killer Whales by an OpenHydro Tidal Turbine Blade (open access)

Assessment of Strike of Adult Killer Whales by an OpenHydro Tidal Turbine Blade

Report to DOE on an analysis to determine the effects of a potential impact to an endangered whale from tidal turbines proposed for deployment in Puget Sound.
Date: February 1, 2012
Creator: Carlson, Thomas J.; Elster, Jennifer L.; Jones, Mark E.; Watson, Bruce E.; Copping, Andrea E.; Watkins, Michael L. et al.
System: The UNT Digital Library
Center for Programming Models for Scalable Parallel Computing - Towards Enhancing OpenMP for Manycore and Heterogeneous Nodes (open access)

Center for Programming Models for Scalable Parallel Computing - Towards Enhancing OpenMP for Manycore and Heterogeneous Nodes

OpenMP was not well recognized at the beginning of the project, around year 2003, because of its limited use in DoE production applications and the inmature hardware support for an efficient implementation. Yet in the recent years, it has been graduately adopted both in HPC applications, mostly in the form of MPI+OpenMP hybrid code, and in mid-scale desktop applications for scientific and experimental studies. We have observed this trend and worked deligiently to improve our OpenMP compiler and runtimes, as well as to work with the OpenMP standard organization to make sure OpenMP are evolved in the direction close to DoE missions. In the Center for Programming Models for Scalable Parallel Computing project, the HPCTools team at the University of Houston (UH), directed by Dr. Barbara Chapman, has been working with project partners, external collaborators and hardware vendors to increase the scalability and applicability of OpenMP for multi-core (and future manycore) platforms and for distributed memory systems by exploring different programming models, language extensions, compiler optimizations, as well as runtime library support.
Date: February 1, 2012
Creator: Chapman, Barbara
System: The UNT Digital Library
Integrated Radiation Transport and Nuclear Fuel Performance for Assembly-Level Simulations (open access)

Integrated Radiation Transport and Nuclear Fuel Performance for Assembly-Level Simulations

The Advanced Multi-Physics (AMP) Nuclear Fuel Performance code (AMPFuel) is focused on predicting the temperature and strain within a nuclear fuel assembly to evaluate the performance and safety of existing and advanced nuclear fuel bundles within existing and advanced nuclear reactors. AMPFuel was extended to include an integrated nuclear fuel assembly capability for (one-way) coupled radiation transport and nuclear fuel assembly thermo-mechanics. This capability is the initial step toward incorporating an improved predictive nuclear fuel assembly modeling capability to accurately account for source-terms and boundary conditions of traditional (single-pin) nuclear fuel performance simulation, such as the neutron flux distribution, coolant conditions, and assembly mechanical stresses. A novel scheme is introduced for transferring the power distribution from the Scale/Denovo (Denovo) radiation transport code (structured, Cartesian mesh with smeared materials within each cell) to AMPFuel (unstructured, hexagonal mesh with a single material within each cell), allowing the use of a relatively coarse spatial mesh (10 million elements) for the radiation transport and a fine spatial mesh (3.3 billion elements) for thermo-mechanics with very little loss of accuracy. In addition, a new nuclear fuel-specific preconditioner was developed to account for the high aspect ratio of each fuel pin (12 feet axially, but 1 …
Date: February 1, 2012
Creator: Clarno, Kevin T; Hamilton, Steven P; Philip, Bobby; Berrill, Mark A; Sampath, Rahul S; Allu, Srikanth et al.
System: The UNT Digital Library
Updating Interconnection Screens for PV System Integration (open access)

Updating Interconnection Screens for PV System Integration

This white paper evaluates the origins and usefulness of the capacity penetration screen, offer short-term solutions which could effectively allow fast-track interconnection to many PV system applications, and considers longer-term solutions for increasing PV deployment levels in a safe and reliable manner while reducing or eliminating the emphasis on the penetration screen. Short-term and longer-term alternatives approaches are offered as examples; however, specific modifications to screening procedures should be discussed with stakeholders and must ultimately be adopted by state and federal regulatory bodies.
Date: February 1, 2012
Creator: Coddington, M.; Mather, B.; Kroposki, B.; Lynn, K.; Razon, A.; Ellis, A. et al.
System: The UNT Digital Library
2011 Vehicle Technologies Market Report (open access)

2011 Vehicle Technologies Market Report

This report details the major trends in U.S. light-duty vehicle and medium/heavy truck markets as well as the underlying trends that caused them. This report is supported by the U.S. Department of Energy s (DOE) Vehicle Technologies Program (VTP), and, in accord with its mission, pays special attention to the progress of high-efficiency and alternative-fuel technologies. This third edition since this report was started in 2008 offers several marked improvements relative to its predecessors. Most significantly, where earlier editions of this report focused on supplying information through an examination of market drivers, new vehicle trends, and supplier data, this edition uses a different structure. After opening with a discussion of energy and economics, this report features a section each on the light-duty vehicle and heavy/medium truck markets, and concluding with a section each on technology and policy. In addition to making this sectional re-alignment, this year s edition of the report also takes a different approach to communicating information. While previous editions relied heavily on text accompanied by auxiliary figures, this third edition relies primarily on charts and graphs to communicate trends. Any accompanying text serves to introduce the trends communication by the graphic and highlight any particularly salient observations. …
Date: February 1, 2012
Creator: Davis, Stacy Cagle; Boundy, Robert Gary & Diegel, Susan W
System: The UNT Digital Library
Complex Adaptive Systems of Systems (CASOS) engineering environment. (open access)

Complex Adaptive Systems of Systems (CASOS) engineering environment.

Complex Adaptive Systems of Systems, or CASoS, are vastly complex physical-socio-technical systems which we must understand to design a secure future for the nation. The Phoenix initiative implements CASoS Engineering principles combining the bottom up Complex Systems and Complex Adaptive Systems view with the top down Systems Engineering and System-of-Systems view. CASoS Engineering theory and practice must be conducted together to develop a discipline that is grounded in reality, extends our understanding of how CASoS behave and allows us to better control the outcomes. The pull of applications (real world problems) is critical to this effort, as is the articulation of a CASoS Engineering Framework that grounds an engineering approach in the theory of complex adaptive systems of systems. Successful application of the CASoS Engineering Framework requires modeling, simulation and analysis (MS and A) capabilities and the cultivation of a CASoS Engineering Community of Practice through knowledge sharing and facilitation. The CASoS Engineering Environment, itself a complex adaptive system of systems, constitutes the two platforms that provide these capabilities.
Date: February 1, 2012
Creator: Detry, Richard Joseph; Linebarger, John Michael; Finley, Patrick D.; Maffitt, S. Louise; Glass, Robert John, Jr.; Beyeler, Walter Eugene et al.
System: The UNT Digital Library
Measure Guideline: Air Sealing Mechanical Closets in Slab-On-Grade Homes (open access)

Measure Guideline: Air Sealing Mechanical Closets in Slab-On-Grade Homes

This measure guideline describes covers two fundamental retrofit strategies for air sealing around air handling systems that are located within the living space in an enclosed closet: one in which all of the equipment is removed and being replaced, and a closet where the equipment is to remain and existing conditions are sealed. It includes the design and installation details necessary to effectively seal the air handler closet and central return system to maximize the efficiency and safety of the space conditioning system.
Date: February 1, 2012
Creator: Dickson, B.
System: The UNT Digital Library
Inverted Metamorphic Multijunction (IMM) Cell Processing Instructions (open access)

Inverted Metamorphic Multijunction (IMM) Cell Processing Instructions

This technical report details the processing schedule used to fabricate Inverted Metamorphic Multijunction (IMM) concentrator solar cells at The National Renewable Energy Laboratory (NREL). These devices are used as experimental test structures to support the research at NREL that is focused on increasing the efficiency of photovoltaic power conversion. They are not intended to be devices suitable for deployment in working concentrator systems primarily because of heat sinking issues. The process schedule was developed to be compatible with small sample sizes and to afford relatively rapid turn-around times, in support of research efforts. The report describes the use of electro deposition of gold for both the back and front contacts. Electro-deposition is used because of its rapid turn around time and because it is a benign metallization technique that is seldom responsible for damage to the semiconductors. The layer transfer technique is detailed including the use of a commercially available adhesive and the etching away of the parent gallium arsenide substrate. Photolithography is used to define front contact grids as well as the mesa area of the cell. Finally, the selective wet chemical etchant system is introduced and its use to reveal the back contact is described.
Date: February 1, 2012
Creator: Duda, A.; Ward, S. & Young, M.
System: The UNT Digital Library
Study of radiative blast waves generated on the Z-beamlet laser. (open access)

Study of radiative blast waves generated on the Z-beamlet laser.

This document describes the original goals of the project to study the Vishniac Overstability on blast waves produced using the Z-Beamlet laser facility as well as the actual results. The proposed work was to build on earlier work on the facility and result in the best characterized set of data for such phenomena in the laboratory. To accomplish the goals it was necessary to modify the existing probe laser at the facility so that it could take multiple images over the course of 1-2 microseconds. Troubles with modifying the probe laser are detailed as well as the work that went into said modifications. The probe laser modification ended up taking the entire length of the project and were the major accomplishment of the research.
Date: February 1, 2012
Creator: Edens, Aaron D. & Schwarz, Jens
System: The UNT Digital Library
Interface modeling to predict well casing damage for big hill strategic petroleum reserve. (open access)

Interface modeling to predict well casing damage for big hill strategic petroleum reserve.

Oil leaks were found in well casings of Caverns 105 and 109 at the Big Hill Strategic Petroleum Reserve site. According to the field observations, two instances of casing damage occurred at the depth of the interface between the caprock and top of salt. This damage could be caused by interface movement induced by cavern volume closure due to salt creep. A three dimensional finite element model, which allows each cavern to be configured individually, was constructed to investigate shear and vertical displacements across each interface. The model contains interfaces between each lithology and a shear zone to examine the interface behavior in a realistic manner. This analysis results indicate that the casings of Caverns 105 and 109 failed by shear stress that exceeded shear strength due to the horizontal movement of the top of salt relative to the caprock, and tensile stress due to the downward movement of the top of salt from the caprock, respectively. The casings of Caverns 101, 110, 111 and 114, located at the far ends of the field, are predicted to be failed by shear stress in the near future. The casings of inmost Caverns 107 and 108 are predicted to be failed by …
Date: February 1, 2012
Creator: Ehgartner, Brian L. & Park, Byoung Yoon
System: The UNT Digital Library
Suggested guidelines for anti-islanding screening. (open access)

Suggested guidelines for anti-islanding screening.

As increasing numbers of photovoltaic (PV) systems are connected to utility systems, distribution engineers are becoming increasingly concerned about the risk of formation of unintentional islands. Utilities desire to keep their systems secure, while not imposing unreasonable burdens on users wishing to connect PV. However, utility experience with these systems is still relatively sparse, so distribution engineers often are uncertain as to when additional protective measures, such as direct transfer trip, are needed to avoid unintentional island formation. In the absence of such certainty, utilities must err on the side of caution, which in some cases may lead to the unnecessary requirement of additional protection. The purpose of this document is to provide distribution engineers and decision makers with guidance on when additional measures or additional study may be prudent, and also on certain cases in which utilities may allow PV installations to proceed without additional study because the risk of an unintentional island is extremely low. The goal is to reduce the number of cases of unnecessary application of additional protection, while giving utilities a basis on which to request additional study in cases where it is warranted.
Date: February 1, 2012
Creator: Ellis, Abraham & Ropp, Michael
System: The UNT Digital Library
Detention of U.S. Persons as Enemy Belligerents (open access)

Detention of U.S. Persons as Enemy Belligerents

This report provides a background to the National Defense Authorization Act for FY2012, the Authorization to use Military Force act, and the President's power to detain "enemy combatants." It then gives a brief introduction to the law of war pertinent to the detention of different categories of individuals and an overview of U.S. practice during wartime to detain persons deemed dangerous to national security. It concludes by discussion Congress's role in prescribing rules for wartime detention as well as legislative proposals in the 112th Congress to address the detention of U.S. persons.
Date: February 1, 2012
Creator: Elsea, Jennifer K.
System: The UNT Digital Library
Detention of U.S. Persons as Enemy Belligerents (open access)

Detention of U.S. Persons as Enemy Belligerents

The detainee provisions passed as part of the National Defense Authorization Act for FY2012 affirm that the Authorization for Use of Military Force in response to the terrorist attacks of September 11, 2001, authorizes the detention of persons captured in connection with hostilities. This report provides a background to the legal issues presented, followed by a brief introduction to the law of war pertinent to the detention of different categories of individuals. An overview of U.S. practice during wartime to detain persons deemed dangerous to the national security is presented.
Date: February 1, 2012
Creator: Elsea, Jennifer K.
System: The UNT Digital Library