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Characterization of Oxy-combustion Impacts in Existing Coal-fired Boilers
Reaction Engineering International (REI) managed a team of experts from University of Utah, Siemens Energy, Praxair, Vattenfall AB, Sandia National Laboratories, Brigham Young University (BYU) and Corrosion Management Ltd. to perform multi-scale experiments, coupled with mechanism development, process modeling and CFD modeling, for both applied and fundamental investigations. The primary objective of this program was to acquire data and develop tools to characterize and predict impacts of CO{sub 2} flue gas recycle and burner feed design on flame characteristics (burnout, NO{sub x}, SO{sub x}, mercury and fine particle emissions, heat transfer) and operational concerns (fouling, slagging and corrosion) inherent in the retrofit of existing coal-fired boilers for oxy-coal combustion. Experimental work was conducted at Sandia National Laboratories’ Entrained Flow Reactor, the University of Utah Industrial Combustion Research Facility, and Brigham Young University. Process modeling and computational fluid dynamics (CFD) modeling was performed at REI. Successful completion of the project objectives resulted in the following key deliverables: 1) Multi-scale test data from 0.1 kW bench-scale, 100 kW and 200 kW laboratory-scale, and 1 MW semi-industrial scale combustors that describe differences in flame characteristics, fouling, slagging and corrosion for coal combustion under air-firing and oxygen-firing conditions, including sensitivity to oxy-burner design and …
Date:
September 30, 2013
Creator:
Adams, Bradley; Davis, Kevin; Senior, Constance; Shim, Hong Shim; Otten, Brydger; Fry, Andrew et al.
Object Type:
Report
System:
The UNT Digital Library
Predictive Science Panel Unclassified Report, LLNL Meeting
None
Date:
September 12, 2013
Creator:
Adams, M
Object Type:
Report
System:
The UNT Digital Library
Compressed Natural Gas (CNG) Transit Bus Experience Survey: April 2009--April 2010
This survey was commissioned by the U.S. Department of Energy (DOE) and the National Renewable Energy Laboratory (NREL) to collect and analyze experiential data and information from a cross-section of U.S. transit agencies with varying degrees of compressed natural gas (CNG) bus and station experience. This information will be used to assist DOE and NREL in determining areas of success and areas where further technical or other assistance might be required, and to assist them in focusing on areas judged by the CNG transit community as priority items.
Date:
September 1, 2010
Creator:
Adams, R. & Horne, D. B.
Object Type:
Report
System:
The UNT Digital Library
U.S. Security Assistance to Lebanon
This report discusses key issues facing U.S. policy makers and Members of Congress when considering U.S. security assistance in the context of U.S. policy toward Lebanon. These key issues include assessing the effectiveness of U.S. assistance programs, assessing overall U.S. policy toward Lebanon, and managing relations with other external actors.
Date:
September 20, 2010
Creator:
Addis, Casey L.
Object Type:
Report
System:
The UNT Digital Library
U.S. Security Assistance to Lebanon
This report discusses key issues facing U.S. policy makers and Members of Congress when considering U.S. security assistance in the context of U.S. policy toward Lebanon. These key issues include assessing the effectiveness of U.S. assistance programs, assessing overall U.S. policy toward Lebanon, and managing relations with other external actors.
Date:
September 20, 2010
Creator:
Addis, Casey L.
Object Type:
Report
System:
The UNT Digital Library
Lifecycle Assessment of Beijing-Area Building Energy Use and Emissions: Summary Findings and Policy Applications
Buildings are at the locus of three trends driving China's increased energy use and emissions: urbanization, growing personal consumption, and surging heavy industrial production. Migration to cities and urban growth create demand for new building construction. Higher levels of per-capita income and consumption drive building operational energy use with demand for higher intensity lighting, thermal comfort, and plug-load power. Demand for new buildings, infrastructure, and electricity requires heavy industrial production. In order to quantify the implications of China's ongoing urbanization, rising personal consumption, and booming heavy industrial sector, this study presents a lifecycle assessment (LCA) of the energy use and carbon emissions related to residential and commercial buildings. The purpose of the LCA model is to quantify the impact of a given building and identify policy linkages to mitigate energy demand and emissions growth related to China's new building construction. As efficiency has become a higher priority with growing energy demand, policy and academic attention to buildings has focused primarily on operational energy use. Existing studies estimate that building operational energy consumption accounts for approximately 25% of total primary energy use in China. However, buildings also require energy for mining, extracting, processing, manufacturing, and transporting materials, as well as energy …
Date:
September 15, 2010
Creator:
Aden, Nathaniel; Qin, Yining & Fridley, David
Object Type:
Report
System:
The UNT Digital Library
Improving Conservation for First-Order System Least Squares Finite-Element Methods
None
Date:
September 5, 2012
Creator:
Adler, J H & Vassilevski, P S
Object Type:
Article
System:
The UNT Digital Library
Gravitomagnetism and Spinor Quantum Mechanics
We give a systematic treatment of a spin 1=2 particle in a combined electromagnetic field and a weak gravitational field that is produced by a slowly moving matter source. This paper continues previous work on a spin zero particle, but it is largely self-contained and may serve as an introduction to spinors in a Riemann space. The analysis is based on the Dirac equation expressed in generally covariant form and coupled minimally to the electromagnetic field. The restriction to a slowly moving matter source, such as the earth, allows us to describe the gravitational field by a gravitoelectric (Newtonian) potential and a gravitomagnetic (frame-dragging) vector potential, the existence of which has recently been experimentally verified. Our main interest is the coupling of the orbital and spin angular momenta of the particle to the gravitomagnetic field. Specifically we calculate the gravitational gyromagnetic ratio as g{sub g} = 1 ; this is to be compared with the electromagnetic gyromagnetic ratio of g{sub e} = 2 for a Dirac electron.
Date:
September 14, 2012
Creator:
Adler, Ronald J.; /Stanford U., HEPL /San Francisco State U.; Chen, Pisin; /Taiwan, Natl. Taiwan U. /KIPAC, Menlo Park /SLAC; Varani, Elisa & /Unlisted
Object Type:
Article
System:
The UNT Digital Library
A Beam Driven Plasma-Wakefield Linear Collider: From Higgs Factory to Multi-TeV
None
Date:
September 30, 2013
Creator:
Adli, E.; Delahaye, J. P.; Gessner, S. J.; Hogan, M. J.; Raubenheimer, T.; An, W. et al.
Object Type:
Article
System:
The UNT Digital Library
A Compact X-Band Linac for an X-Ray FEL
With the growing demand for FEL light sources, cost issues are being reevaluated. To make the machines more compact, higher frequency room temperature linacs are being considered, specifically ones using C-band (5.7 GHz) rf technology, for which 40 MV/m gradients are achievable. In this paper, we show that an X-band (11.4 GHz) linac using the technology developed for NLC/GLC can provide an even lower cost solution. In particular, stable operation is possible at gradients of 100 MV/m for single bunch operation and 70 MV/m for multibunch operation. The concern, of course, is whether the stronger wakefields will lead to unacceptable emittance dilution. However, we show that the small emittances produced in a 250 MeV, low bunch charge, LCLS-like S-band injector and bunch compressor can be preserved in a multi-GeV X-band linac with reasonable alignment tolerances. The successful lasing and operation of the LCLS [1] has generated world-wide interest in X-ray FELs. The demand for access to such a light source by researchers eager to harness the capabilities of this new tool far exceeds the numbers that can be accommodated, spurring plans for additional facilities. Along with cost, spatial considerations become increasingly important for a hard X-ray machine driven by a …
Date:
September 12, 2011
Creator:
Adolphsen, Chris; Huang, Zhirong; Bane, Karl L. F.; Li, Zenghai; Zhou, Feng; Wang, Faya et al.
Object Type:
Article
System:
The UNT Digital Library
PRELIMINARY REPORT ON EVALUATION OF POTENTIAL ELUANTS FOR NON-ACID ELUTION OF CESIUM FROM RESORCINOL-FORMALDEHYDE RESIN
Small-column ion exchange (SCIX) units installed in high-level waste tanks to remove Cs-137 from highly alkaline salt solutions are among the waste treatment plans in the DOE-complex. Spherical Resorcinol-Formaldehyde (sRF) is the ion exchange resin selected for use in the Hanford Waste Treatment and Immobilization Plant (WTP). It is also the primary ion exchange material under consideration for SCIX at the Hanford site. The elution step of the multi-step ion exchange process is typically done with 0.5 M nitric acid. An acid eluant is a potential hazard in the event of a spill, leak, etc. because the high-level waste tanks are made of carbon steel. Corrosion and associated structural damage may ensue. Studies are ongoing to explore non-acid elution as an alternative. Batch contact sorption equilibrium screening tests have been conducted with 36 potential non-acid eluants. The sorption tests involve equilibrating each cesium-containing eluant solution with the sRF resin for 48 hours at 25 C in a shaker oven. In the sorption tests, an eluant is deemed to have a high cesium elution potential if it minimizes cesium sorption onto the sRF resin. The top candidates (based on lowest cesium sorption distribution coefficients) include ammonium carbonate, ammonium carbonate/ammonium hydroxide, ammonium …
Date:
September 1, 2010
Creator:
Adu-Wusu, K. & Pennebaker, F.
Object Type:
Report
System:
The UNT Digital Library
Improved resolution of hydrocarbon structures and constitutional isomers in complex mixtures using Gas Chromatography-Vacuum Ultraviolet-Mass Spectrometry (GC-VUV-MS) (Supplementary Info)
Understanding the composition of complex hydrocarbon mixtures is important for environmental studies in a variety of fields, but many prevalent compounds cannot be confidently identified using traditional gas chromatography-mass spectrometry (GC-MS) techniques. This work uses vacuum-ultraviolet (VUV) ionization to elucidate the structures of a traditionally"unresolved complex mixture" by separating components by GC retention time, tR, and mass-to-charge ratio, m/Q, which are used to determine carbon number, NC, and the number of rings and double bonds, NDBE. Constitutional isomers are resolved based on tR, enabling the most complete quantitative analysis to date of structural isomers in an environmentally-relevant hydrocarbon mixture. Unknown compounds are classified in this work by carbon number, degree of saturation, presence of rings, and degree of branching, providing structural constraints. The capabilities of this analysis are explored using diesel fuel, in which constitutional isomer distribution patterns are shown to be reproducible between carbon numbers and follow predictable rules. Nearly half of the aliphatic hydrocarbon mass is shown to be branched, suggesting branching is more important in diesel fuel than previously shown. The classification of unknown hydrocarbons and the resolution of constitutional isomers significantly improves resolution capabilities for any complex hydrocarbon mixture.
Date:
September 5, 2011
Creator:
Aerosol Dynamics Inc.,; Aerodyne Research, Inc.,; Tofwerk AG, Thun, Switzerland; Isaacman, Gabriel; Wilson, Kevin R.; Chan, Arthur W. H. et al.
Object Type:
Article
System:
The UNT Digital Library
LIPSS Free-Electron Laser Searches for Dark Matter
A variety of Dark Matter particle candidates have been hypothesized by physics Beyond the Standard Model (BSM) in the very light (10{sup -6} - 10{sup -3} eV) range. In the past decade several international groups have conducted laboratory experiments designed to either produce such particles or extend the boundaries in parameter space. The LIght Pseudo-scalar and Scalar Search (LIPSS) Collaboration, using the 'Light Shining through a Wall' (LSW) technique, passes the high average power photon beam from Jefferson Lab's Free-Electron Laser through a magnetic field upstream from a mirror and optical beam dump. Light Neutral Bosons (LNBs), generated by coupling of photons with the magnetic field, pass through the mirror ('the Wall') into an identical magnetic field where they revert to detectable photons by the same coupling process. While no evidence of LNBs was evident, new scalar coupling boundaries were established. New constraints were also determined for hypothetical para-photons and for millicharged fermions. We will describe our experimental setup and results for LNBs, para-photons, and milli-charged fermions. Plans for chameleon particle searches are underway.
Date:
September 1, 2011
Creator:
Afanaciev, Andrei; Beard, Kevin; Biallas, George; Boyce, James R; Minarni, M; Ramdon, R et al.
Object Type:
Article
System:
The UNT Digital Library
Light Water Reactor Sustainability Program Demonst
The online monitoring of active components project
Date:
September 1, 2013
Creator:
Agarwal, Vivek; Lybeck, Nancy J. & Matacia, Laura C.
Object Type:
Report
System:
The UNT Digital Library
Monte Carlo Simulation Tool Installation and Operation Guide
This document provides information on software and procedures for Monte Carlo simulations based on the Geant4 toolkit, the ROOT data analysis software and the CRY cosmic ray library. These tools have been chosen for its application to shield design and activation studies as part of the simulation task for the Majorana Collaboration. This document includes instructions for installation, operation and modification of the simulation code in a high cyber-security computing environment, such as the Pacific Northwest National Laboratory network. It is intended as a living document, and will be periodically updated. It is a starting point for information collection by an experimenter, and is not the definitive source. Users should consult with one of the authors for guidance on how to find the most current information for their needs.
Date:
September 2, 2013
Creator:
Aguayo Navarrete, Estanislao; Ankney, Austin S.; Berguson, Timothy J.; Kouzes, Richard T.; Orrell, John L.; Troy, Meredith D. et al.
Object Type:
Report
System:
The UNT Digital Library
Cosmic Ray Interactions in Shielding Materials
This document provides a detailed study of materials used to shield against the hadronic particles from cosmic ray showers at Earth’s surface. This work was motivated by the need for a shield that minimizes activation of the enriched germanium during transport for the MAJORANA collaboration. The materials suitable for cosmic-ray shield design are materials such as lead and iron that will stop the primary protons, and materials like polyethylene, borated polyethylene, concrete and water that will stop the induced neutrons. The interaction of the different cosmic-ray components at ground level (protons, neutrons, muons) with their wide energy range (from kilo-electron volts to giga-electron volts) is a complex calculation. Monte Carlo calculations have proven to be a suitable tool for the simulation of nucleon transport, including hadron interactions and radioactive isotope production. The industry standard Monte Carlo simulation tool, Geant4, was used for this study. The result of this study is the assertion that activation at Earth’s surface is a result of the neutronic and protonic components of the cosmic-ray shower. The best material to shield against these cosmic-ray components is iron, which has the best combination of primary shielding and minimal secondary neutron production.
Date:
September 8, 2011
Creator:
Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Ankney, Austin S.; Orrell, John L.; Berguson, Timothy J. & Troy, Meredith D.
Object Type:
Report
System:
The UNT Digital Library
Recommendations for a Static Cosmic Ray Shield for Enriched Germanium Detectors
This document provides a detailed study of cost and materials that could be used to shield the detector material of the international Tonne-scale germanium neutrinoless double-beta decay experiment from hadronic particles from cosmic ray showers at the Earth's surface. This work was motivated by the need for a shield that minimizes activation of the enriched germanium during storage; in particular, when the detector material is being worked on at the detector manufacturer's facility. This work considers two options for shielding the detector material from cosmic ray particles. One option is to use a pre-existing structure already located near the detector manufacturer, such as Canberra Industries in Meriden, Connecticut. The other option is to build a shield onsite at a detector manufacturer's site. This paper presents a cost and efficiency analysis of such construction.
Date:
September 21, 2011
Creator:
Aguayo Navarrete, Estanislao; Orrell, John L.; Ankney, Austin S. & Berguson, Timothy J.
Object Type:
Report
System:
The UNT Digital Library
The Future of the Eurozone and U.S. Interests
This report details the consequences of the European financial crisis of 2010 beginning with the economic fallout of the Greek economy. It then highlights six factors that would be instrumental regarding the "Eurozones" future.
Date:
September 14, 2010
Creator:
Ahearn, Raymond J.; Jackson, James K.; Nelson, Rebecca M. & Weiss, Martin A.
Object Type:
Report
System:
The UNT Digital Library
Enabling R&D for accurate simulation of non-ideal explosives.
We implemented two numerical simulation capabilities essential to reliably predicting the effect of non-ideal explosives (NXs). To begin to be able to treat the multiple, competing, multi-step reaction paths and slower kinetics of NXs, Sandia's CTH shock physics code was extended to include the TIGER thermochemical equilibrium solver as an in-line routine. To facilitate efficient exploration of reaction pathways that need to be identified for the CTH simulations, we implemented in Sandia's LAMMPS molecular dynamics code the MSST method, which is a reactive molecular dynamics technique for simulating steady shock wave response. Our preliminary demonstrations of these two capabilities serve several purposes: (i) they demonstrate proof-of-principle for our approach; (ii) they provide illustration of the applicability of the new functionality; and (iii) they begin to characterize the use of the new functionality and identify where improvements will be needed for the ultimate capability to meet national security needs. Next steps are discussed.
Date:
September 1, 2010
Creator:
Aidun, John Bahram; Thompson, Aidan Patrick & Schmitt, Robert Gerard
Object Type:
Report
System:
The UNT Digital Library
Fermi Large Area Telescope Observations of the Supernova Remnant G8.7-0.1
We present a detailed analysis of the GeV gamma-ray emission toward the supernova remnant (SNR) G8.7-0.1 with the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope. An investigation of the relationship between G8.7-0.1 and the TeV unidentified source HESS J1804-216 provides us with an important clue on diffusion process of cosmic rays if particle acceleration operates in the SNR. The GeV gamma-ray emission is extended with most of the emission in positional coincidence with the SNR G8.7-0.1 and a lesser part located outside the western boundary of G8.7-0.1. The region of the gamma-ray emission overlaps spatially connected molecular clouds, implying a physical connection for the gamma-ray structure. The total gamma-ray spectrum measured with LAT from 200 MeV-100 GeV can be described by a broken power-law function with a break of 2.4 {+-} 0.6 (stat) {+-} 1.2 (sys) GeV, and photon indices of 2.10 {+-} 0.06 (stat) {+-} 0.10 (sys) below the break and 2.70 {+-} 0.12 (stat) {+-} 0.14 (sys) above the break. Given the spatial association among the gamma rays, the radio emission of G8.7-0.1, and the molecular clouds, the decay of p0s produced by particles accelerated in the SNR and hitting the molecular clouds naturally …
Date:
September 14, 2012
Creator:
Ajello, M.; Allafort, A.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D. et al.
Object Type:
Article
System:
The UNT Digital Library
ANALYSIS OF PASSIVATED SURFACES FOR MASS SPECTROMETER INLET SYSTEMS BY AUGER ELECTRON AND X-RAY PHOTOELECTRON SPECTROSCOPY
Stainless steel coupons approximately 0.5' in diameter and 0.125' thick were passivated with five different surface treatments and an untreated coupon was left as a control. These surface treatments are being explored for use in tritium storage containers. These coupons were made to allow surface analysis of the surface treatments using well-know surface analysis techniques. Depth profiles using Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS) were performed on these coupons to characterize the surface and near surface regions. Scanning electron microscope (SEM) images were collected as well. All of the surface treatments studied here appear to change the surface morphology dramatically, as evidenced by lack of tool marks on the treated samples. In terms of the passivation treatment, Vendors A-D appeared to have oxide layers that were very similar in thickness to each other (0.7-0.9 nm thick) as well as the untreated samples (the untreated sample oxide layers appeared to be somewhat larger). Vendor E's silicon coating appears to be on the order of 200 nm thick.
Date:
September 1, 2010
Creator:
Ajo, H. & Clark, E.
Object Type:
Report
System:
The UNT Digital Library
The Overseas Private Investment Corporation: Background and Legislative Issues
This report provides: (1) a background on Overseas Private Investment Corporation (OPIC) origins and program operations; (2) discussion of the international development finance context; and (3) analysis of key issues for Congress related to OPIC.
Date:
September 25, 2013
Creator:
Akhtar, Shayerah I.
Object Type:
Report
System:
The UNT Digital Library
Ex-Im Bank: No Quorum, No Problem?
This report discusses the operation on a limited basis of the Export-Import Bank (Ex-Im Bank) despite a renewal of its general statutory charter through FY2019 (P.L. 114-94,
Date:
September 15, 2016
Creator:
Akhtar, Shayerah Ilias
Object Type:
Report
System:
The UNT Digital Library
Export-Import Bank (Ex-Im Bank) Reauthorization
None
Date:
September 2, 2014
Creator:
Akhtar, Shayerah Ilias
Object Type:
Report
System:
The UNT Digital Library