Study of Heterogeneouse Processes Related to the Chemistry of Tropospheric Oxidants and Aerosols (open access)

Study of Heterogeneouse Processes Related to the Chemistry of Tropospheric Oxidants and Aerosols

The objective of the studies was to elucidate the heterogeneous chemistry of tropospheric aerosols. Experiments were designed to measure both specifically needed parameters, and to obtain systematic data required to build a fundamental understanding of the nature of gas-surface physical and chemical interactions
Date: February 13, 2013
Creator: Davidovits, Paul; Worsnop, D R; Jayne, J T & Colb, C E
Object Type: Report
System: The UNT Digital Library
The Color Glass Condensate, Glasma and the Quark Gluon Plasma in the Context of Recent pPb Results from LHC (open access)

The Color Glass Condensate, Glasma and the Quark Gluon Plasma in the Context of Recent pPb Results from LHC

N/A
Date: February 2, 2013
Creator: McLerran, L.
Object Type: Article
System: The UNT Digital Library
Preliminary photovoltaic arc-fault prognostic tests using sacrificial fiber optic cabling. (open access)

Preliminary photovoltaic arc-fault prognostic tests using sacrificial fiber optic cabling.

Through the New Mexico Small Business Assistance Program, Sandia National Laboratories worked with Sentient Business Systems, Inc. to develop and test a novel photovoltaic (PV) arc-fault detection system. The system operates by pairing translucent polymeric fiber optic sensors with electrical circuitry so that any external abrasion to the system or internal heating causes the fiber optic connection to fail or detectably degrade. A periodic pulse of light is sent through the optical path using a transmitter-receiver pair. If the receiver does not detect the pulse, an alarm is sounded and the PV system can be de-energized. This technology has the unique ability to prognostically determine impending failures to the electrical system in two ways: (a) the optical connection is severed prior to physical abrasion or cutting of PV DC electrical conductors, and (b) the polymeric fiber optic cable melts via Joule heating before an arc-fault is established through corrosion. Three arc-faults were created in different configurations found in PV systems with the integrated fiber optic system to determine the feasibility of the technology. In each case, the fiber optic cable was broken and the system annunciated the fault.
Date: February 1, 2013
Creator: Johnson, Jay; Blemel, Kenneth D. & Peter, Francis
Object Type: Report
System: The UNT Digital Library
Plasma-Accelerated Flyer-Plates for Equation of State Studies (open access)

Plasma-Accelerated Flyer-Plates for Equation of State Studies

None
Date: February 13, 2012
Creator: Fratanduono, D E; Smith, R F; Boehly, T R; Eggert, J H; Braun, D G & Collins, G W
Object Type: Article
System: The UNT Digital Library
Guiding Center Equations for Ideal Magnetohydrodynamic Modes (open access)

Guiding Center Equations for Ideal Magnetohydrodynamic Modes

Guiding center simulations are routinely used for the discovery of mode-particle resonances in tokamaks, for both resistive and ideal instabilities and to find modifications of particle distributions caused by a given spectrum of modes, including large scale avalanches during events with a number of large amplitude modes. One of the most fundamental properties of ideal magnetohydrodynamics is the condition that plasma motion cannot change magnetic topology. The conventional representation of ideal magnetohydrodynamic modes by perturbing a toroidal equilibrium field through δ~B = ∇ X (ξ X B) however perturbs the magnetic topology, introducing extraneous magnetic islands in the field. A proper treatment of an ideal perturbation involves a full Lagrangian displacement of the field due to the perturbation and conserves magnetic topology as it should. In order to examine the effect of ideal magnetohydrodynamic modes on particle trajectories the guiding center equations should include a correct Lagrangian treatment. Guiding center equations for an ideal displacement ξ are derived which perserve the magnetic topology and are used to examine mode particle resonances in toroidal confinement devices. These simulations are compared to others which are identical in all respects except that they use the linear representation for the field. Unlike the case …
Date: February 21, 2013
Creator: White, Roscoe B.
Object Type: Report
System: The UNT Digital Library
Vehicle Technologies' Fact of the Week 2012 (open access)

Vehicle Technologies' Fact of the Week 2012

Each week the U.S. Department of Energy s Vehicle Technology Office (VTO) posts a Fact of the Week on their website: http://www1.eere.energy.gov/vehiclesandfuels/ . These Facts provide statistical information, usually in the form of charts and tables, on vehicle sales, fuel economy, gasoline prices, and other transportation-related trends. Each Fact is a stand-alone page that includes a graph, text explaining the significance of the data, the supporting information on which the graph was based, and the source of the data. A link to the current week s Fact is available on the VTO homepage, but older Facts are archived and still available at: http://www1.eere.energy.gov/vehiclesandfuels/facts/. This report is a compilation of the Facts that were posted during calendar year 2012. The Facts were written and prepared by staff in Oak Ridge National Laboratory's Center for Transportation Analysis.
Date: February 1, 2013
Creator: Davis, Stacy Cagle; Diegel, Susan W; Moore, Sheila A & Boundy, Robert Gary
Object Type: Report
System: The UNT Digital Library
Analysis of Pu-Only Partitioning Strategies in LMFBR Fuel Cycles (open access)

Analysis of Pu-Only Partitioning Strategies in LMFBR Fuel Cycles

Sodium cooled Fast Reactors (SFR) have been under consideration for production of electricity, fissile material production, and for destruction of transuranics for decades. The neutron economy of a SFR can be operated in one of two ways. One possibility is to operate the reactor in a transuranic burner mode which has been the focus of active R&D in the last 15 years. However, prior to that the focus was on breeding transuranics. This later mode of managing the neutron economy relies on ensuring the maximum fuel utilization possible in such a way as to maximize the amount of plutonium produced per unit of fission energy in the reactor core. The goal of maximizing plutonium production in this study is as fissile feed stock for the production of MOX fuel to be used in Light Water Reactors (LWR). Throughout the l970’s, this fuel cycle scenario was the focus of much research by the Atomic Energy Commission in the event that uranium supplies would be scarce. To date, there has been sufficient uranium to supply the once through nuclear fuel cycle. However, interest in a synergistic relationship Liquid Metal Fast Breeder Reactors (LMFBR) and a consumer LWR fleet persists, prompting this study. …
Date: February 1, 2013
Creator: Bays, Samuel & Youinou, Gilles
Object Type: Report
System: The UNT Digital Library
EGS rock reactions with Supercritical CO2 saturated with water and water saturated with Supercritical CO2 (open access)

EGS rock reactions with Supercritical CO2 saturated with water and water saturated with Supercritical CO2

EGS using CO2 as a working fluid will likely involve hydro-shearing low-permeability hot rock reservoirs with a water solution. After that process, the fractures will be flushed with CO2 that is maintained under supercritical conditions (> 70 bars). Much of the injected water in the main fracture will be flushed out with the initial CO2 injection; however side fractures, micro fractures, and the lower portion of the fracture will contain connate water that will interact with the rock and the injected CO2. Dissolution/precipitation reactions in the resulting scCO2/brine/rock systems have the potential to significantly alter reservoir permeability, so it is important to understand where these precipitates form and how are they related to the evolving ‘free’ connate water in the system. To examine dissolution / precipitation behavior in such systems over time, we have conducted non-stirred batch experiments in the laboratory with pure minerals, sandstone, and basalt coupons with brine solution spiked with MnCl2 and scCO2. The coupons are exposed to liquid water saturated with scCO2 and extend above the water surface allowing the upper portion of the coupons to be exposed to scCO2 saturated with water. The coupons were subsequently analyzed using SEM to determine the location of reactions …
Date: February 1, 2013
Creator: Mattson, Earl D.; McLing, Travis L.; Smith, William & Palmer, Carl
Object Type: Article
System: The UNT Digital Library
Highly Insulating Windows Volume Purchase Program Final Report (open access)

Highly Insulating Windows Volume Purchase Program Final Report

This report summarizes the Highly Insulating Windows Volume Purchase Program, conduced by PNNL for DOE-BTP, including a summary of outcomes and lessons learned.
Date: February 1, 2013
Creator: Parker, Graham B.; Mapes, Terry S. & Zalis, W. J.
Object Type: Report
System: The UNT Digital Library
Analysis of the Impact of Balancing Area Cooperation on the Operation of WECC and the Compounding Effect of Wind and Solar Generation (open access)

Analysis of the Impact of Balancing Area Cooperation on the Operation of WECC and the Compounding Effect of Wind and Solar Generation

It is the intent of this analysis to examine the operational benefits of increased cooperation between a large number of WECC operating regions.
Date: February 1, 2013
Creator: Jordan, G. & Piwko, D.
Object Type: Report
System: The UNT Digital Library
A VUV Photoionization Study of the Combustion-Relevant Reaction of the Phenyl Radical (C6H5) with Propylene (C3H6) in a High Temperature Chemical Reactor (open access)

A VUV Photoionization Study of the Combustion-Relevant Reaction of the Phenyl Radical (C6H5) with Propylene (C3H6) in a High Temperature Chemical Reactor

We studied the reaction of phenyl radicals (C6H5) with propylene (C3H6) exploiting a high temperature chemical reactor under combustion-like conditions (300 Torr, 1,200-1,500 K). The reaction products were probed in a supersonic beam by utilizing tunable vacuum ultraviolet (VUV) radiation from the Advanced Light Source and recording the photoionization efficiency (PIE) curves at mass-to-charge ratios of m/z = 118 (C9H10+) and m/z = 104 (C8H8+). Our results suggest that the methyl and atomic hydrogen losses are the two major reaction pathways with branching ratios of 86 10 percent and 14 10 percent. The isomer distributions were probed by fitting the recorded PIE curves with a linear combination of the PIE curves of the individual C9H10 and C8H8 isomers. Styrene (C6H5C2H3) was found to be the exclusive product contributing to m/z = 104 (C8H8+), whereas 3-phenylpropene, cis-1-phenylpropene, and 2-phenylpropene with branching ratios of 96 4 percent, 3 3 percent, and 1 1 percent could account for signal at m/z = 118 (C9H10+). Although searched for carefully, no evidence of the bicyclic indane molecule could be provided. The reaction mechanisms and branching ratios are explained in terms of electronic structure calculations nicely agreeing with a recent crossed molecular beam study on this …
Date: February 22, 2012
Creator: Manoa, University of Hawaii at; Laboratories, Sandia National; Zhang, Fangtong; Kaiser, Ralf I.; Golan, Amir; Ahmed, Musahid et al.
Object Type: Article
System: The UNT Digital Library
PV output smoothing using a battery and natural gas engine-generator. (open access)

PV output smoothing using a battery and natural gas engine-generator.

In some situations involving weak grids or high penetration scenarios, the variability of photovoltaic systems can affect the local electrical grid. In order to mitigate destabilizing effects of power fluctuations, an energy storage device or other controllable generation or load can be used. This paper describes the development of a controller for coordinated operation of a small gas engine-generator set (genset) and a battery for smoothing PV plant output. There are a number of benefits derived from using a traditional generation resource in combination with the battery; the variability of the photovoltaic system can be reduced to a specific level with a smaller battery and Power Conditioning System (PCS) and the lifetime of the battery can be extended. The controller was designed specifically for a PV/energy storage project (Prosperity) and a gas engine-generator (Mesa Del Sol) currently operating on the same feeder in Albuquerque, New Mexico. A number of smoothing simulations of the Prosperity PV were conducted using power data collected from the site. By adjusting the control parameters, tradeoffs between battery use and ramp rates could be tuned. A cost function was created to optimize the control in order to balance, in this example, the need to have low …
Date: February 1, 2013
Creator: Johnson, Jay; Ellis, Abraham; Denda, Atsushi; Morino, Kimio; Shinji, Takao; Ogata, Takao et al.
Object Type: Report
System: The UNT Digital Library
Final scientific and technical report for grant DE-AI02-93ER40784: Fundamental Physics with Cold Neutrons (open access)

Final scientific and technical report for grant DE-AI02-93ER40784: Fundamental Physics with Cold Neutrons

There have been a growing number of notable results in fundamental neutron physics, which are briefly summarized.
Date: February 7, 2013
Creator: Dewey, Maynard, S.
Object Type: Report
System: The UNT Digital Library
Energy Recovery Linac: Beam Dynamics, Parameters and Physics to be learned (open access)

Energy Recovery Linac: Beam Dynamics, Parameters and Physics to be learned

N/A
Date: February 1, 2010
Creator: D., Kayran
Object Type: Report
System: The UNT Digital Library
Thermal dissociation behavior and dissociation enthalpies of methane-carbon dioxide mixed hydrates (open access)

Thermal dissociation behavior and dissociation enthalpies of methane-carbon dioxide mixed hydrates

Replacement of methane with carbon dioxide in hydrate has been proposed as a strategy for geologic sequestration of carbon dioxide (CO{sub 2}) and/or production of methane (CH{sub 4}) from natural hydrate deposits. This replacement strategy requires a better understanding of the thermodynamic characteristics of binary mixtures of CH{sub 4} and CO{sub 2} hydrate (CH{sub 4}-CO{sub 2} mixed hydrates), as well as thermophysical property changes during gas exchange. This study explores the thermal dissociation behavior and dissociation enthalpies of CH{sub 4}-CO{sub 2} mixed hydrates. We prepared CH{sub 4}-CO{sub 2} mixed hydrate samples from two different, well-defined gas mixtures. During thermal dissociation of a CH{sub 4}-CO{sub 2} mixed hydrate sample, gas samples from the head space were periodically collected and analyzed using gas chromatography. The changes in CH{sub 4}-CO{sub 2} compositions in both the vapor phase and hydrate phase during dissociation were estimated based on the gas chromatography measurements. It was found that the CO{sub 2} concentration in the vapor phase became richer during dissociation because the initial hydrate composition contained relatively more CO{sub 2} than the vapor phase. The composition change in the vapor phase during hydrate dissociation affected the dissociation pressure and temperature; the richer CO{sub 2} in the vapor …
Date: February 15, 2011
Creator: Kwon, T.H.; Kneafsey, T.J. & Rees, E.V.L.
Object Type: Article
System: The UNT Digital Library
Enhanced Ex-Vessel Analysis for Fukushima Daiichi Unit 1: Melt Spreading and Core-Concrete Interaction Analyses with MELTSPREAD & CORQUENCH (open access)

Enhanced Ex-Vessel Analysis for Fukushima Daiichi Unit 1: Melt Spreading and Core-Concrete Interaction Analyses with MELTSPREAD & CORQUENCH

None
Date: February 1, 2013
Creator: Robb, Kevin R; Farmer, Mitchell & Francis, Matthew W
Object Type: Report
System: The UNT Digital Library
Final Technical Report (open access)

Final Technical Report

The research project focuses on the following topics: a) removal of artifacts in the Doppler spectra from the ARM cloud radars, b) development of the second generation Active Remote Sensing of Cloud Layers (ARSCL) cloud data products, and c) evaluation of ARM cloud property retrievals within the framework of the EarthCARE simulator. We continue to pursue research on areas related to radiative transfer, atmospheric heating rates and related dynamics (topics of interest to the ARM science community at this time) and to contribute on an ad-hoc basis to the science of other ARM-supported principal investigators.
Date: February 22, 2010
Creator: Eugene Clothiaux, Johannes Verlinde, Jerry Harrington
Object Type: Report
System: The UNT Digital Library
SLAC Cosmic Ray Telescope Facility (open access)

SLAC Cosmic Ray Telescope Facility

SLAC does not have a test beam for the HEP detector development at present. We have therefore created a cosmic ray telescope (CRT) facility, which is presently being used to test the FDIRC prototype. We have used it in the past to debug this prototype with the original SLAC electronics before going to the ESA test beam. Presently, it is used to test a new waveform digitizing electronics developed by the University of Hawaii, and we are also planning to incorporate the new Orsay TDC/ADC electronics. As a next step, we plan to put in a full size DIRC bar box with a new focusing optics, and test it together with a final SuberB electronics. The CRT is located in building 121 at SLAC. We anticipate more users to join in the future. This purpose of this note is to provide an introductory manual for newcomers.
Date: February 15, 2010
Creator: Va'vra, J.
Object Type: Report
System: The UNT Digital Library
Report of On-Site Inspection Workshop-20 (open access)

Report of On-Site Inspection Workshop-20

None
Date: February 6, 2013
Creator: Sweeney, J.
Object Type: Report
System: The UNT Digital Library
Atmosphere-Land-Surface Interaction over the Southern Great Plains: Diagnosis of Mechanisms from SGP ARM Data (open access)

Atmosphere-Land-Surface Interaction over the Southern Great Plains: Diagnosis of Mechanisms from SGP ARM Data

Work reported included analysis of pentad (5 day) averaged data, proposal of a hypothesis concerning the key role of the Atlantic Multi-decadal Oscillation in 20th century drought and wet periods over the Great Plains, analysis of recurrent super-synoptic evolution of the Great Plains low-level jet, and study of pentad evolution of the 1988 drought and 1993 flood over the Great Plains from a NARR perspective on the atmospheric and terrestrial water balance.
Date: February 1, 2013
Creator: Nigam, Sumant
Object Type: Report
System: The UNT Digital Library
CO and CO2 Hydrogenation to Methanol Calculated Using the BEEF-vdW Functional (open access)

CO and CO2 Hydrogenation to Methanol Calculated Using the BEEF-vdW Functional

None
Date: February 21, 2013
Creator: Studt, Felix; Abild-Pedersen, Frank; Varley, Joel B. & Norskov, Jens K.
Object Type: Article
System: The UNT Digital Library
Turbine Reliability and Operability Optimization through the use of Direct Detection Lidar Final Technical Report (open access)

Turbine Reliability and Operability Optimization through the use of Direct Detection Lidar Final Technical Report

The goal of this Department of Energy (DOE) project is to increase wind turbine efficiency and reliability with the use of a Light Detection and Ranging (LIDAR) system. The LIDAR provides wind speed and direction data that can be used to help mitigate the fatigue stress on the turbine blades and internal components caused by wind gusts, sub-optimal pointing and reactionary speed or RPM changes. This effort will have a significant impact on the operation and maintenance costs of turbines across the industry. During the course of the project, Michigan Aerospace Corporation (MAC) modified and tested a prototype direct detection wind LIDAR instrument; the resulting LIDAR design considered all aspects of wind turbine LIDAR operation from mounting, assembly, and environmental operating conditions to laser safety. Additionally, in co-operation with our partners, the National Renewable Energy Lab and the Colorado School of Mines, progress was made in LIDAR performance modeling as well as LIDAR feed forward control system modeling and simulation. The results of this investigation showed that using LIDAR measurements to change between baseline and extreme event controllers in a switching architecture can reduce damage equivalent loads on blades and tower, and produce higher mean power output due to fewer …
Date: February 1, 2013
Creator: Johnson, David K.; Lewis, Matthew J.; Pavlich, Jane C.; Wright, Alan D.; Johnson, Kathryn E. & Pace, Andrew M.
Object Type: Report
System: The UNT Digital Library
2012 Annual Progress Report for Propulsion Materials (open access)

2012 Annual Progress Report for Propulsion Materials

This report is about the progress report for Propulsion Materials.
Date: February 1, 2013
Creator: Haynes, James A
Object Type: Report
System: The UNT Digital Library
Ridge-Valley Graphs: Combinatorial Ridge Detection Using Jacobi Sets (open access)

Ridge-Valley Graphs: Combinatorial Ridge Detection Using Jacobi Sets

None
Date: February 4, 2011
Creator: Norgard, G & Bremer, P T
Object Type: Report
System: The UNT Digital Library