From Nucleons To Nuclei To Fusion Reactions (open access)

From Nucleons To Nuclei To Fusion Reactions

Nuclei are prototypes of many-body open quantum systems. Complex aggregates of protons and neutrons that interact through forces arising from quantum chromo-dynamics, nuclei exhibit both bound and unbound states, which can be strongly coupled. In this respect, one of the major challenges for computational nuclear physics, is to provide a unified description of structural and reaction properties of nuclei that is based on the fundamental underlying physics: the constituent nucleons and the realistic interactions among them. This requires a combination of innovative theoretical approaches and high-performance computing. In this contribution, we present one of such promising techniques, the ab initio no-core shell model/resonating-group method, and discuss applications to light nuclei scattering and fusion reactions that power stars and Earth-base fusion facilities.
Date: February 15, 2012
Creator: Quaglioni, S; Navratil, P; Roth, R & Horiuchi, W
Object Type: Article
System: The UNT Digital Library
MIX and Instability Growth from Oblique Shock (open access)

MIX and Instability Growth from Oblique Shock

We have studied the formation and evolution of shock-induced mix resulting from interface features in a divergent cylindrical geometry. In this research a cylindrical core of high-explosive was detonated to create an oblique shock wave and accelerate the interface. The interfaces studied were between the high-explosive/aluminum, aluminum/plastic, and finally plastic/air. Pre-emplaced surface features added to the aluminum were used to modify this interface. Time sequence radiographic imaging quantified the resulting instability formation from the growth phase to over 60 {micro}s post-detonation. Thus allowing the study of the onset of mix and evolution to turbulence. The plastic used here was porous polyethylene. Radiographic image data are compared with numerical simulations of the experiments.
Date: July 22, 2011
Creator: Molitoris, J D; Batteux, J D; Garza, R G; Tringe, J W; Souers, P C & Forbes, J W
Object Type: Article
System: The UNT Digital Library
Hydrogen Storage in Metal-Organic Frameworks (open access)

Hydrogen Storage in Metal-Organic Frameworks

Conventional storage of large amounts of hydrogen in its molecular form is difficult and expensive because it requires employing either extremely high pressure gas or very low temperature liquid. Because of the importance of hydrogen as a fuel, the DOE has set system targets for hydrogen storage of gravimetric (5.5 wt%) and volumetric (40 g L-1) densities to be achieved by 2015. Given that these are system goals, a practical material will need to have higher capacity when the weight of the tank and associated cooling or regeneration system is considered. The size and weight of these components will vary substantially depending on whether the material operates by a chemisorption or physisorption mechanism. In the latter case, metal-organic frameworks (MOFs) have recently been identified as promising adsorbents for hydrogen storage, although little data is available for their sorption behavior. This grant was focused on the study of MOFs with these specific objectives. (1) To examine the effects of functionalization, catenation, and variation of the metal oxide and organic linkers on the low-pressure hydrogen adsorption properties of MOFs. (2) To develop a strategy for producing MOFs with high surface area and porosity to reduce the dead space and increase the hydrogen …
Date: April 26, 2012
Creator: Yaghi, Omar M.
Object Type: Report
System: The UNT Digital Library
10 CFR 830 Major Modification Determination for the ATR Diesel Bus (E-3) and Switchgear Replacement (open access)

10 CFR 830 Major Modification Determination for the ATR Diesel Bus (E-3) and Switchgear Replacement

Near term replacement of aging and obsolescent original ATR equipment has become important to ensure ATR capability in support of NE’s long term national missions. To that end, a mission needs statement has been prepared for a non-major system acquisition which is comprised of three interdependent subprojects. The first project, subject of this determination, will replace the existent diesel-electrical bus (E-3) and associated switchgear. More specifically, INL proposes transitioning ATR to 100% commercial power with appropriate emergency backup to include: • Provide commercial power as the normal source of power to the ATR loads currently supplied by diesel-electric power. • Provide backup power to the critical ATR loads in the event of a loss of commercial power. • Replace obsolescent critical ATR power distribution equipment, e.g., switchgear, transformers, motor control centers, distribution panels. Completion of this and two other age-related projects (primary coolant pump and motor replacement and emergency firewater injection system replacement) will resolve major age related operational issues plus make a significant contribution in sustaining the ATR safety and reliability profile. The major modification criteria evaluation of the project pre-conceptual design identified several issues make the project a major modification: 1. Evaluation Criteria #2 (Footprint change). The addition …
Date: May 1, 2011
Creator: Duckwtiz, Noel
Object Type: Report
System: The UNT Digital Library
Wind energy Computerized Maintenance Management System (CMMS) : data collection recommendations for reliability analysis. (open access)

Wind energy Computerized Maintenance Management System (CMMS) : data collection recommendations for reliability analysis.

This report addresses the general data requirements for reliability analysis of fielded wind turbines and other wind plant equipment. The report provides a rationale for why this data should be collected, a list of the data needed to support reliability and availability analysis, and specific data recommendations for a Computerized Maintenance Management System (CMMS) to support automated analysis. This data collection recommendations report was written by Sandia National Laboratories to address the general data requirements for reliability analysis of operating wind turbines. This report is intended to help develop a basic understanding of the data needed for reliability analysis from a Computerized Maintenance Management System (CMMS) and other data systems. The report provides a rationale for why this data should be collected, a list of the data needed to support reliability and availability analysis, and specific recommendations for a CMMS to support automated analysis. Though written for reliability analysis of wind turbines, much of the information is applicable to a wider variety of equipment and analysis and reporting needs. The 'Motivation' section of this report provides a rationale for collecting and analyzing field data for reliability analysis. The benefits of this type of effort can include increased energy delivered, decreased …
Date: January 1, 2012
Creator: Peters, Valerie A. & Ogilvie, Alistair B.
Object Type: Report
System: The UNT Digital Library
Calibrating transport lines using LOCO techniques (open access)

Calibrating transport lines using LOCO techniques

With the 12GeV upgrade underway at CEBAF, there is a need to re-characterize the beamlines after the modifications made to it to accommodate running at higher energies. We present a linear perturbation approach to calibrating the optics model of transport lines. This method is adapted from the LOCO method in use for storage rings. We consider the effect of quadrupole errors, dipole construction errors as well as beam position monitors and correctors calibrations. The ideal model is expanded to first order in Taylor series of the quadrupole errors. A set of difference orbits obtained by exciting the correctors along the beamline is taken, yielding the measured response matrix. An iterative procedure is invoked and the quadrupole errors as well as beam position monitors and corrector calibration factors are obtained. Here we present details of the method and results of first measurements at CEBAF in early 2011.
Date: September 1, 2011
Creator: Roblin, Yves
Object Type: Article
System: The UNT Digital Library
Event-by-event study of photon observables in spontaneous and thermal fission (open access)

Event-by-event study of photon observables in spontaneous and thermal fission

None
Date: September 26, 2012
Creator: Vogt, R & Randrup, J
Object Type: Article
System: The UNT Digital Library
4 kW Test of Solid Oxide Electrolysis Stacks with Advanced Electrode-Supported Cells (open access)

4 kW Test of Solid Oxide Electrolysis Stacks with Advanced Electrode-Supported Cells

A new test stand has been developed at the Idaho National Laboratory for multi-kW testing of solid oxide electrolysis stacks. This test stand will initially be operated at the 4 KW scale. The 4 kW tests will include two 60-cell stacks operating in parallel in a single hot zone. The stacks are internally manifolded with an inverted-U flow pattern and an active area of 100 cm2 per cell. Process gases to and from the two stacks are distributed from common inlet/outlet tubing using a custom base manifold unit that also serves as the bottom current collector plate. The solid oxide cells incorporate a negative-electrode-supported multi-layer design with nickel-zirconia cermet negative electrodes, thin-film yttria-stabilized zirconia electrolytes, and multi-layer lanthanum ferrite-based positive electrodes. Treated metallic interconnects with integral flow channels separate the cells and electrode gases. Sealing is accomplished with compliant mica-glass seals. A spring-loaded test fixture is used for mechanical stack compression. Due to the power level and the large number of cells in the hot zone, process gas flow rates are high and heat recuperation is required to preheat the cold inlet gases upstream of the furnace. Heat recuperation is achieved by means of two inconel tube-in-tube counter-flow heat exchangers. …
Date: June 1, 2012
Creator: O'Brien, J. E.; Zhang, X.; Housley, G. K.; Moore-McAteer, L. & Tao, G.
Object Type: Article
System: The UNT Digital Library
Gamma ray imaging of the imploding shell using NIS hardware (open access)

Gamma ray imaging of the imploding shell using NIS hardware

None
Date: June 12, 2013
Creator: Izumi, N & Tommasini, R
Object Type: Report
System: The UNT Digital Library
Commercial Central Air Conditioners, Purchasing Specifications for Energy-Efficient Products (Fact Sheet) (open access)

Commercial Central Air Conditioners, Purchasing Specifications for Energy-Efficient Products (Fact Sheet)

Energy efficiency purchasing specifications for federal procurements of commercial central air conditioners.
Date: February 1, 2011
Creator: unknown
Object Type: Report
System: The UNT Digital Library
REMOVAL OF LEGACY PLUTONIUM MATERIALS FROM SWEDEN (open access)

REMOVAL OF LEGACY PLUTONIUM MATERIALS FROM SWEDEN

U.S. Department of Energy’s National Nuclear Security Administration (NNSA) Office of Global Threat Reduction (GTRI) recently removed legacy plutonium materials from Sweden in collaboration with AB SVAFO, Sweden. This paper details the activities undertaken through the U.S. receiving site (Savannah River Site (SRS)) to support the characterization, stabilization, packaging and removal of legacy plutonium materials from Sweden in 2012. This effort was undertaken as part of GTRI’s Gap Materials Program and culminated with the successful removal of plutonium from Sweden as announced at the 2012 Nuclear Security Summit. The removal and shipment of plutonium materials to the United States was the first of its kind under NNSA’s Global Threat Reduction Initiative. The Environmental Assessment for the U.S. receipt of gap plutonium material was approved in May 2010. Since then, the multi-year process yielded many first time accomplishments associated with plutonium packaging and transport activities including the application of the of DOE-STD-3013 stabilization requirements to treat plutonium materials outside the U.S., the development of an acceptance criteria for receipt of plutonium from a foreign country, the development and application of a versatile process flow sheet for the packaging of legacy plutonium materials, the identification of a plutonium container configuration, the first …
Date: August 18, 2013
Creator: Dunn, Kerry A.; Bellamy, J. Steve; Chandler, Greg T.; Iyer, Natraj C.; Koenig, Rich E.; Leduc, D. et al.
Object Type: Article
System: The UNT Digital Library

High Throughput Pretreatment and Enzyme Hydrolysis of Biomass: Screening Recalcitrance in Large Sample Populations

Presentation on the execution of the first high-throughput thermochemical pretreatment/enzyme digestion pipeline for screening biomass for recalcitrance.
Date: October 1, 2010
Creator: Decker, S. R.
Object Type: Presentation
System: The UNT Digital Library
Advanced inactive materials for improved lithium-ion battery safety. (open access)

Advanced inactive materials for improved lithium-ion battery safety.

None
Date: November 1, 2012
Creator: Orendorff, Christopher J.; Nagasubramanian, Ganesan; Lambert, Timothy N.; Fenton, Kyle Ross; Apblett, Christopher Alan; Shaddix, Christopher R. et al.
Object Type: Report
System: The UNT Digital Library
2010-2012 Hestec Bowl (open access)

2010-2012 Hestec Bowl

This is the Financial Status Report for this project for the period from May 1, 2012 to September 30, 2012.
Date: October 29, 2012
Creator: De La Rosa Ortiz, Stacey
Object Type: Text
System: The UNT Digital Library
NREL Invention Speeds Solar Cell Quality Testing for Industry (Fact Sheet) (open access)

NREL Invention Speeds Solar Cell Quality Testing for Industry (Fact Sheet)

A solid-state optical system, invented by the National Renewable Energy Laboratory (NREL), measures solar cell quantum efficiency (QE) in less than a second, enabling a suite of new capabilities for solar cell manufacturers. QE is a measurement of how cells respond to light across the solar spectrum, but traditional methods for measuring QE had been too slow, limiting its application to small samples pulled from the production line and analyzed in laboratories. NREL's technique, commercialized by Tau Science as the FlashQE(TM) system, uses a solid-state light source, synchronized electronics, and advanced mathematical analysis to parallel-process QE data in a tiny fraction of the time required by the current method, allowing its use on every solar cell passing through a production line.
Date: August 1, 2013
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Summary of operations and performance of the Utica aquifer and North Lake Basin Wetlands restoration project in December 2010-November 2011. (open access)

Summary of operations and performance of the Utica aquifer and North Lake Basin Wetlands restoration project in December 2010-November 2011.

None
Date: September 19, 2012
Creator: LaFreniere, L. M.
Object Type: Report
System: The UNT Digital Library
Energy Retrofit Field Study and Best Practices in a Hot-Humid Climate (open access)

Energy Retrofit Field Study and Best Practices in a Hot-Humid Climate

Energy efficiency improvement as a component of comprehensive renovation was investigated under U.S. Department of Energy (DOE) funding of the Building America Partnership for Improved Residential Construction (BA-PIRC). Researchers at the Florida Solar Energy Center (FSEC) worked with affordable housing partners renovating foreclosed homes built from the 1950's through the 2000's in the hot-humid climate (within the Southern census region), primarily in Florida. Researchers targeted a 30% improvement in whole-house energy efficiency along with the health and safety, durability, and comfort guidelines outlined in DOE's Builders Challenge Program (Version 1) Quality Criteria.
Date: March 1, 2013
Creator: McIvaine, J.; Sutherland, K. & Martin, E.
Object Type: Report
System: The UNT Digital Library
Max Tech and Beyond: High-Intensity Discharge Lamps (open access)

Max Tech and Beyond: High-Intensity Discharge Lamps

High-intensity discharge (HID) lamps are most often found in industrial and commercial applications, and are the light source of choice in street and area lighting, and sports stadium illumination. HID lamps are produced in three types - mercury vapor (MV), high pressure sodium (HPS) and metal halide (MH). Of these, MV and MH are considered white-light sources (although the MV exhibits poor color rendering) and HPS produces a yellow-orange color light. A fourth lamp, low-pressure sodium (LPS), is not a HID lamp by definition, but it is used in similar applications and thus is often grouped with HID lamps. With the notable exception of MV which is comparatively inefficient and in decline in the US from both a sales and installed stock point of view; HPS, LPS and MH all have efficacies over 100 lumens per watt. The figure below presents the efficacy trends over time for commercially available HID lamps and LPS, starting with MV and LPS in 1930's followed by the development of HPS and MH in the 1960's. In HID lamps, light is generated by creating an electric arc between two electrodes in an arc tube. The particles in the arc are partially ionized, making them electrically …
Date: April 1, 2012
Creator: Scholand, Michael
Object Type: Report
System: The UNT Digital Library
Developement of 3D Vertically Integrated Pattern Recognition Associative Memory (VIPRAM) (open access)

Developement of 3D Vertically Integrated Pattern Recognition Associative Memory (VIPRAM)

Many next-generation physics experiments will be characterized by the collection of large quantities of data, taken in rapid succession, from which scientists will have to unravel the underlying physical processes. In most cases, large backgrounds will overwhelm the physics signal. Since the quantity of data that can be stored for later analysis is limited, real-time event selection is imperative to retain the interesting events while rejecting the background. Scaling of current technologies is unlikely to satisfy the scientific needs of future projects, so investments in transformational new technologies need to be made. For example, future particle physics experiments looking for rare processes will have to address the demanding challenges of fast pattern recognition in triggering as detector hit density becomes significantly higher due to the high luminosity required to produce the rare processes. In this proposal, we intend to develop hardware-based technology that significantly advances the state-of-the-art for fast pattern recognition within and outside HEP using the 3D vertical integration technology that has emerged recently in industry. The ultimate physics reach of the LHC experiments will crucially depend on the tracking trigger's ability to help discriminate between interesting rare events and the background. Hardware-based pattern recognition for fast triggering on …
Date: April 13, 2011
Creator: Deputch, G.; Hoff, J.; Lipton, R.; Liu, T.; Olsen, J.; Ramberg, E. et al.
Object Type: Report
System: The UNT Digital Library
Efficient Graph Based Assembly of Short-Read Sequences on Hybrid Core Architecture (open access)

Efficient Graph Based Assembly of Short-Read Sequences on Hybrid Core Architecture

Advanced architectures can deliver dramatically increased throughput for genomics and proteomics applications, reducing time-to-completion in some cases from days to minutes. One such architecture, hybrid-core computing, marries a traditional x86 environment with a reconfigurable coprocessor, based on field programmable gate array (FPGA) technology. In addition to higher throughput, increased performance can fundamentally improve research quality by allowing more accurate, previously impractical approaches. We will discuss the approach used by Convey?s de Bruijn graph constructor for short-read, de-novo assembly. Bioinformatics applications that have random access patterns to large memory spaces, such as graph-based algorithms, experience memory performance limitations on cache-based x86 servers. Convey?s highly parallel memory subsystem allows application-specific logic to simultaneously access 8192 individual words in memory, significantly increasing effective memory bandwidth over cache-based memory systems. Many algorithms, such as Velvet and other de Bruijn graph based, short-read, de-novo assemblers, can greatly benefit from this type of memory architecture. Furthermore, small data type operations (four nucleotides can be represented in two bits) make more efficient use of logic gates than the data types dictated by conventional programming models.JGI is comparing the performance of Convey?s graph constructor and Velvet on both synthetic and real data. We will present preliminary results on …
Date: March 22, 2011
Creator: Sczyrba, Alex; Pratap, Abhishek; Canon, Shane; Han, James; Copeland, Alex; Wang, Zhong et al.
Object Type: Article
System: The UNT Digital Library
Multitasking mesoporous nanomaterials for biorefinery applications (open access)

Multitasking mesoporous nanomaterials for biorefinery applications

Mesoporous silica nanoparticles (MSNs) have attracted great interest for last two decades due to their unique and advantageous structural properties, such as high surface area, pore volume, stable mesostructure, tunable pore size and controllable particle morphology. The robust silica framework provides sites for organic modifications, making MSNs ideal platforms for adsorbents and supported organocatalysts. In addition, the pores of MSNs provide cavities/ channels for incorporation of metal and metal oxide nanoparticle catalysts. These supported metal nanoparticle catalysts benefit from confined local environments to enhance their activity and selectivity for various reactions. Biomass is considered as a sustainable feedstock with potential to replace diminishing fossil fuels for the production of biofuels. Among several strategies, one of the promising methods of biofuel production from biomass is to reduce the oxygen content of the feedstock in order to improve the energy density. This can be achieved by creating C-C bonds between biomass derived intermediates to increase the molecular weight of the final hydrocarbon molecules. In this context, pore size and organic functionality of MSNs are varied to obtain the ideal catalyst for a C-C bond forming reaction: the aldol condensation. The mechanistic aspects of this reaction in supported heterogeneous catalysts are explored. The …
Date: May 2, 2013
Creator: Kandel, Kapil
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Collapsing Bubble in Metal for High Energy Density Physics Study (open access)

Collapsing Bubble in Metal for High Energy Density Physics Study

This paper presents a new idea to produce matter in the high energy density physics (HEDP) regime in the laboratory using an intense ion beam. A gas bubble created inside a solid metal may collapse by driving it with an intense ion beam. The melted metal will compress the gas bubble and supply extra energy to it. Simulations show that the spherical implosion ratio can be about 5 and at the stagnation point, the maximum density, temperature and pressure inside the gas bubble can go up to nearly 2 times solid density, 10 eV and a few megabar (Mbar) respectively. The proposed experiment is the first to permit access into the Mbar regime with existing or near-term ion facilities, and opens up possibilities for new physics gained through careful comparisons of simulations with measurements of quantities like stagnation radius, peak temperature and peak pressure at the metal wall.
Date: April 13, 2011
Creator: Ng, S. F.; Barnard, J. J.; Leung, P. T. & Yu, S. S.
Object Type: Article
System: The UNT Digital Library
Fighting Fire with Fire: Modeling the Datacenter-Scale Effects of Targeted Superlattice Thermal Management (open access)

Fighting Fire with Fire: Modeling the Datacenter-Scale Effects of Targeted Superlattice Thermal Management

Local thermal hot-spots in microprocessors lead to worst case provisioning of global cooling resources, especially in large-scale systems. However, efficiency of cooling solutions degrade non-linearly with supply temperature, resulting in high power consumption and cost in cooling - 50 {approx} 100% of IT power. Recent advances in active cooling techniques have shown on-chip thermoelectric coolers (TECs) to be very efficient at selectively eliminating small hot-spots, where applying current to a superlattice film deposited between silicon and the heat spreader results in a Peltier effect that spreads the heat and lowers the temperature of the hot-spot significantly to improve chip reliability. In this paper, we propose that hot-spot mitigation using thermoelectric coolers can be used as a power management mechanism to allow global coolers to be provisioned for a better worst case temperature leading to substantial savings in cooling power. In order to quantify the potential power savings from using TECs in data center servers, we present a detailed power model that integrates on-chip dynamic and leakage power sources, heat diffusion through the entire chip, TEC and global cooler efficiencies, and all their mutual interactions. Our multiscale analysis shows that, for a typical data center, TECs allow global coolers to operate …
Date: November 11, 2010
Creator: Biswas, S; Tiwari, M; Theogarajan, L; Sherwood, T P & Chong, F T
Object Type: Article
System: The UNT Digital Library
Solar Energy Windows and Smart IR Switchable Building Technologies (open access)

Solar Energy Windows and Smart IR Switchable Building Technologies

The three building envelope functions with the largest impact on the energy usage are illumination, energy flux and energy production. In general, these three functions are addressed separately in the building design. A step change toward a zero-energy building can be achieved with a glazing system that combines these three functions and their control into a single unit. In particular, significant value could be realized if illumination into the building is dynamically controlled such that it occurs during periods of low load on the grid (e.g., morning) to augment illumination supplied by interior lights and then to have that same light diverted to PV energy production and the thermal energy rejected during periods of high load on the grid. The objective of this project is to investigate the feasibility of a glazing unit design that integrates these three key functions (illumination and energy flux control, and power production) into a single module.
Date: September 30, 2011
Creator: McCarny, James & Kornish, Brian
Object Type: Report
System: The UNT Digital Library