Final Assembly of Cryogenic Targets for NIF (open access)

Final Assembly of Cryogenic Targets for NIF

None
Date: February 9, 2010
Creator: Swisher, M F; Montesanti, R C; Alger, E T; Castro, C; Dzenitis, E G; Edwards, G J et al.
Object Type: Article
System: The UNT Digital Library
Analysis of Drought Impacts on Electricity Production in the Western and Texas Interconnections of the United States. (open access)

Analysis of Drought Impacts on Electricity Production in the Western and Texas Interconnections of the United States.

Electricity generation relies heavily on water resources and their availability. To examine the interdependence of energy and water in the electricity context, the impacts of a severe drought to assess the risk posed by drought to electricity generation within the western and Texas interconnections has been examined. The historical drought patterns in the western United States were analyzed, and the risk posed by drought to electricity generation within the region was evaluated. The results of this effort will be used to develop scenarios for medium- and long-term transmission modeling and planning efforts by the Western Electricity Coordination Council (WECC) and the Electric Reliability Council of Texas (ERCOT). The study was performed in response to a request developed by the Western Governors Association in conjunction with the transmission modeling teams at the participating interconnections. It is part of a U.S. Department of Energy-sponsored, national laboratory-led research effort to develop tools related to the interdependency of energy and water as part of a larger interconnection-wide transmission planning project funded under the American Recovery and Reinvestment Act. This study accomplished three main objectives. It provided a thorough literature review of recent studies of drought and the potential implications for electricity generation. It analyzed …
Date: February 9, 2012
Creator: Harto, C. B.; Yan, Y. E.; Demissie, Y. K.; Elcock, D.; Tidwell, V. C.; Hallett, K. et al.
Object Type: Report
System: The UNT Digital Library
PREPARING FOR A SUCCESSFUL EVMS CERTIFICATION (open access)

PREPARING FOR A SUCCESSFUL EVMS CERTIFICATION

The client, a government agency, requires its contractor to obtain an Earned Value Management System (EVMS) certification that meets the intent of ANSI/EIA-748-B, Earned Value Management Systems. The contractor has extensive experience with certification preparation, having completed two certifications within two years. Information from a previous EVMS certification and internal system surveillances are used to prepare for client-based EVMS certifications and bi-annual surveillances. The contractor also sent members of its group to assist other companies preparing for surveillances and certifications to perform 'Black Hat Reviews.' This paper is a lessons learned on preparing a team for EVMS certification. The information is also applicable for surveillances, since the contractor prepares its team for the surveillance in the same manner as the initial certification. Some of the areas covered include required documents, tracing the data through the systems, Control Account Manager (CAM) preparation, and system verification.
Date: February 9, 2011
Creator: SL, CROWE & AD, BASCHE
Object Type: Article
System: The UNT Digital Library
Linear and Nonlinear Spectroscopic Probing of Solute Interactions with Chemically Modified Silica Surfaces (open access)

Linear and Nonlinear Spectroscopic Probing of Solute Interactions with Chemically Modified Silica Surfaces

Solar energy conversion through biology would provide a renewable and nonpolluting abundance of energy. The bacterium Halobacterium salinarum converts solar to electrical energy by virtue of a transmembrane protein, bacteriorhodopsin. This transmembrane protein pumps protons across a nonconducting bilayer upon irradiation with green light. The bacterium evolved to perform this function inefficiently. If we were able to understand this process to engineer this protein for efficiency, then inexpensive energy production could be achieved. There are tens of thousands of different types of halobacteria, giving the opportunity to study different efficiencies and relating these to the protein structures. Technology does not yet exist to perform such screening. The goal of this research is to generate new separation technology that can ultimately enable such screening. This involves creating a method for separating oriented and functional transmembrane proteins that remain in an electrically insulating lipid bilayer, with aqueous solutions on either side of the bilayer. A pH change across the lipid bilayer upon irradiation of a known concentration of proteins would probe function. Differences in proton pumping efficiency for different proteins variants would provide structure-function information for engineering the proteins. A schematic diagram from the original proposal is shown here. The idea is …
Date: February 9, 2011
Creator: Wirth, Mary J
Object Type: Report
System: The UNT Digital Library
Laser supported solid state absorption fronts in silica (open access)

Laser supported solid state absorption fronts in silica

We develop a model based on simulation and experiment that explains the behavior of solid-state laser-supported absorption fronts generated in fused silica during high intensity (up to 5GW/cm{sup 2}) laser exposure. We find that the absorption front velocity is constant in time and is nearly linear in laser intensity. Further, this model can explain the dependence of laser damage site size on these parameters. This behavior is driven principally by the temperature-activated deep sub band-gap optical absorptivity, free electron transport and thermal diffusion in defect-free silica for temperatures up to 15,000K and pressures < 15GPa. The regime of parameter space critical to this problem spans and extends that measured by other means. It serves as a platform for understanding general laser-matter interactions in dielectrics under a variety of conditions.
Date: February 9, 2010
Creator: Carr, C W & Bude, J D
Object Type: Article
System: The UNT Digital Library
Finding Regions of Interest on Toroidal Meshes (open access)

Finding Regions of Interest on Toroidal Meshes

Fusion promises to provide clean and safe energy, and a considerable amount of research effort is underway to turn this aspiration intoreality. This work focuses on a building block for analyzing data produced from the simulation of microturbulence in magnetic confinementfusion devices: the task of efficiently extracting regions of interest. Like many other simulations where a large amount of data are produced,the careful study of ``interesting'' parts of the data is critical to gain understanding. In this paper, we present an efficient approach forfinding these regions of interest. Our approach takes full advantage of the underlying mesh structure in magnetic coordinates to produce acompact representation of the mesh points inside the regions and an efficient connected component labeling algorithm for constructingregions from points. This approach scales linearly with the surface area of the regions of interest instead of the volume as shown with bothcomputational complexity analysis and experimental measurements. Furthermore, this new approach is 100s of times faster than a recentlypublished method based on Cartesian coordinates.
Date: February 9, 2011
Creator: Wu, Kesheng; Sinha, Rishi R; Jones, Chad; Ethier, Stephane; Klasky, Scott; Ma, Kwan-Liu et al.
Object Type: Article
System: The UNT Digital Library
Calculation of the Non-Inductive Current Profile in High-Performance NSTX Plasmas (open access)

Calculation of the Non-Inductive Current Profile in High-Performance NSTX Plasmas

The constituents of the current profile have been computed for a wide range of high-performance plasmas in NSTX [M. Ono, et al., Nuclear Fusion 40, 557 (2000)]; these include cases designed to maximize the non-inductive fraction, pulse length, toroidal-β, or stored energy. In the absence of low-frequency MHD activity, good agreement is found between the reconstructed current profile and that predicted by summing the independently calculated inductive, pressure-driven, and neutral beam currents, without the need to invoke any anomalous beam ion diffusion. Exceptions occur, for instance, when there are toroidal Alfven eigenmode avalanches or coupled m/n=1/1+2/1 kink-tearing modes. In these cases, the addition of a spatially and temporally dependent fast ion diffusivity can reduce the core beam current drive, restoring agreement between the reconstructed profile and the summed constituents, as well as bringing better agreement between the simulated and measured neutron emission rate. An upper bound on the fast ion diffusivity of ~0.5-1 m2/sec is found in “MHD-free” discharges, based on the neutron emission, time rate of change of the neutron signal when a neutral beam is stepped, and reconstructed on-axis current density.
Date: February 9, 2011
Creator: Gerhardt, S P; Gates, D; Kaye, S; Menard, J; Bell, M G; Bell, R E et al.
Object Type: Report
System: The UNT Digital Library
Vacuum-Ultraviolet Photoionization and Mass Spectrometric Characterization of Lignin Monomers Coniferyl and Sinapyl Alcohols (open access)

Vacuum-Ultraviolet Photoionization and Mass Spectrometric Characterization of Lignin Monomers Coniferyl and Sinapyl Alcohols

The fragmentation mechanisms of monolignols under various energetic processes are studied with jet-cooled thermal desorption molecular beam (TDMB) mass spectrometry (MS), 25 keV Bi3+ secondary ion MS (SIMS), synchrotron vacuum-ultraviolet secondary neutral MS (VUV-SNMS) and theoretical methods. Experimental and calculated appearance energies of fragments observed in TDMB MS indicate that the coniferyl alcohol photoionization mass spectra contain the molecular parent and several dissociative photoionization products. Similar results obtained for sinapyl alcohol are also discussed briefly. Ionization energies of 7.60 eV ? 0.05 eV for coniferyl alcohol and<7.4 eV for both sinapyl and dihydrosinapyl alcohols are determined. The positive ion SIMS spectrum of coniferyl alcohol shares few characteristic peaks (m/z = 137 and 151) with the TDMB mass spectra, shows extensive fragmentation, and does not exhibit clear molecular parent signals. VUV-SNMS spectra, on the other hand, are dominated by the parent ion and main fragments also present in the TDMB spectra. Molecular fragmentation in VUV-SNMS spectra can be reduced by increasing the extraction delay time. Some features resembling the SIMS spectra are also observed in the desorbed neutral products. The monolignol VUV-SNMS peaks shared with the TDMB mass spectra suggest that dissociative photoionization of ion-sputtered neutral molecules predominate in the VUV-SNMS …
Date: February 9, 2011
Creator: Takahashi, Lynelle K.; Zhou, Jia; Kostko, Oleg; Golan, Amir; Leone, Stephen R. & Ahmed, Musahid
Object Type: Article
System: The UNT Digital Library
Design of Genomic Signatures of Pathogen Identification & Characterization (open access)

Design of Genomic Signatures of Pathogen Identification & Characterization

This chapter will address some of the many issues associated with the identification of signatures based on genomic DNA/RNA, which can be used to identify and characterize pathogens for biodefense and microbial forensic goals. For the purposes of this chapter, we define a signature as one or more strings of contiguous genomic DNA or RNA bases that are sufficient to identify a pathogenic target of interest at the desired resolution and which could be instantiated with particular detection chemistry on a particular platform. The target may be a whole organism, an individual functional mechanism (e.g., a toxin gene), or simply a nucleic acid indicative of the organism. The desired resolution will vary with each program's goals but could easily range from family to genus to species to strain to isolate. The resolution may not be taxonomically based but rather pan-mechanistic in nature: detecting virulence or antibiotic-resistance genes shared by multiple microbes. Entire industries exist around different detection chemistries and instrument platforms for identification of pathogens, and we will only briefly mention a few of the techniques that we have used at Lawrence Livermore National Laboratory (LLNL) to support our biosecurity-related work since 2000. Most nucleic acid based detection chemistries involve …
Date: February 9, 2010
Creator: Slezak, T.; Gardner, S.; Allen, J.; Vitalis, E. & Jaing, C.
Object Type: Book
System: The UNT Digital Library
Development of a Conceptual Chum Salmon Emergence Model for Ives Island (open access)

Development of a Conceptual Chum Salmon Emergence Model for Ives Island

The objective of the study described herein was to develop a conceptual model of chum salmon emergence that was based on empirical water temperature of the riverbed and river in specific locations where chum salmon spawn in the Ives Island area. The conceptual model was developed using water temperature data that have been collected in the past and are currently being collected in the Ives Island area. The model will be useful to system operators who need to estimate the complete distribution of chum salmon emergence (first emergence through final emergence) in order to balance chum salmon redd protection and power system operation.
Date: February 9, 2011
Creator: Murray, Christopher J.; Geist, David R.; Arntzen, Evan V.; Bott, Yi-Ju & Nabelek, Marc A.
Object Type: Report
System: The UNT Digital Library
Scientific and Computational Challenges of the Fusion Simulation Program (FSP) (open access)

Scientific and Computational Challenges of the Fusion Simulation Program (FSP)

This paper highlights the scientific and computational challenges facing the Fusion Simulation Program (FSP) a major national initiative in the United States with the primary objective being to enable scientific discovery of important new plasma phenomena with associated understanding that emerges only upon integration. This requires developing a predictive integrated simulation capability for magnetically-confined fusion plasmas that are properly validated against experiments in regimes relevant for producing practical fusion energy. It is expected to provide a suite of advanced modeling tools for reliably predicting fusion device behavior with comprehensive and targeted science-based simulations of nonlinearly-coupled phenomena in the core plasma, edge plasma, and wall region on time and space scales required for fusion energy production. As such, it will strive to embody the most current theoretical and experimental understanding of magnetic fusion plasmas and to provide a living framework for the simulation of such plasmas as the associated physics understanding continues to advance over the next several decades. Substantive progress on answering the outstanding scientific questions in the field will drive the FSP toward its ultimate goal of developing the ability to predict the behavior of plasma discharges in toroidal magnetic fusion devices with high physics fidelity on all relevant …
Date: February 9, 2011
Creator: Tang, William M.
Object Type: Article
System: The UNT Digital Library
Technical assessment of compressed hydrogen storage tank systems for automotive applications. (open access)

Technical assessment of compressed hydrogen storage tank systems for automotive applications.

The performance and cost of compressed hydrogen storage tank systems has been assessed and compared to the U.S. Department of Energy (DOE) 2010, 2015, and ultimate targets for automotive applications. The on-board performance and high-volume manufacturing cost were determined for compressed hydrogen tanks with design pressures of 350 bar ({approx}5000 psi) and 700 bar ({approx}10,000 psi) capable of storing 5.6 kg of usable hydrogen. The off-board performance and cost of delivering compressed hydrogen was determined for hydrogen produced by central steam methane reforming (SMR). The main conclusions of the assessment are that the 350-bar compressed storage system has the potential to meet the 2010 and 2015 targets for system gravimetric capacity but will not likely meet any of the system targets for volumetric capacity or cost, given our base case assumptions. The 700-bar compressed storage system has the potential to meet only the 2010 target for system gravimetric capacity and is not likely to meet any of the system targets for volumetric capacity or cost, despite the fact that its volumetric capacity is much higher than that of the 350-bar system. Both the 350-bar and 700-bar systems come close to meeting the Well-to-Tank (WTT) efficiency target, but fall short by …
Date: February 9, 2011
Creator: Hua, T. Q.; Ahluwalia, R. K.; Peng, J. K.; Kromer, M.; Lasher, S.; McKenney, K. et al.
Object Type: Report
System: The UNT Digital Library
2011 Raditation & Climate Gordon Research Conference (July 10-15 2011- Colby College, Waterville, Maine) (open access)

2011 Raditation & Climate Gordon Research Conference (July 10-15 2011- Colby College, Waterville, Maine)

The 2011 Gordon Research Conference on Radiation and Climate will present cutting-edge research on outstanding issues in climate change, particularly those in which the interactions between clouds, aerosols, and precipitation play a major role. The Conference will feature a broad range of topics, including grand challenges in atmospheric radiation and climate, cloud and water vapor feedbacks, aerosol-cloud-precipitation-climate interactions across scales, new approaches for remote sensing and in-situ observations of clouds, aerosols and precipitation, and multi-scale modeling challenges. The invited speakers will present the most important recent advances and future challenges in these areas. The Conference will bring together a collection of leading investigators who are at the forefront of their field, and will provide opportunities for scientists, especially junior scientists and graduate students, to present their work in poster format and exchange ideas with leaders in the field. The collegial atmosphere of this Conference, with programmed discussion sessions as well as opportunities for informal gatherings in the afternoons and evenings, provides an avenue for scientists from different disciplines to brainstorm and promotes cross-disciplinary collaborations in the various research areas represented.
Date: February 9, 2012
Creator: Hoggblom, Prof. Max
Object Type: Article
System: The UNT Digital Library
NIF Target Assembly Metrology and Results (open access)

NIF Target Assembly Metrology and Results

None
Date: February 9, 2010
Creator: Alger, E T; Kroll, J J; Hughes, J; Dzenitis, E G; Montesanti, R; Swisher, M et al.
Object Type: Article
System: The UNT Digital Library
An imaging proton spectrometer for short-pulse laser plasma experiments (open access)

An imaging proton spectrometer for short-pulse laser plasma experiments

Ultra intense short pulse laser pulses incident on solid targets can generate energetic protons. In additions to their potentially important applications such as in cancer treatments and proton fast ignition, these protons are essential to understand the complex physics of intense laser plasma interaction. To better understand these laser-produced protons, we designed and constructed a novel, spatially imaging proton spectrometer that will not only provide at high-resolution the energy distribution, but also the protons angular characteristics. The information obtained from this spectrometer compliments those from other methods using radiochromic film packs, CR39 films and other protons spectrometers. The basic characterizations and example data from this diagnostics will be presented. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344, as part of the Cimarron project funded by LDRD-09SI11.
Date: February 9, 2010
Creator: Chen, H.; Hazi, A.; van Maren, R.; Chen, S.; Fuchs, J.; Gauthier, M. et al.
Object Type: Article
System: The UNT Digital Library
Ergonomics and Engineering - Designing for the perfect fit...even for Cinderella's glass slipper (open access)

Ergonomics and Engineering - Designing for the perfect fit...even for Cinderella's glass slipper

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Date: February 9, 2010
Creator: Alexandre, Melanie & Naca, Christine
Object Type: Report
System: The UNT Digital Library