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Health Effects from Advanced Combustion and Fuel Technologies
This document requires a separate file for the figures. It is for DOE's Office of Vehicle Technologies Annual Report
Date:
January 1, 2010
Creator:
Barone, Teresa L.; Parks, James E., Jr.; Lewis, Samuel Arthur, Sr. & Connatser, Raynella M.
Object Type:
Report
System:
The UNT Digital Library
Higgs searches at the Tevatron
We present the latest results on searches for the standard and beyond-the-standard model Higgs bosons in proton-antiproton collisions at {radical}s = 1.96 TeV by the CDF and D0 experiments at the Fermilab Tevatron. No significant excess is observed above the expected background, and the cross section limits for the Higgs bosons are calculated. It is noticed that the standard model Higgs boson in the mass range 163-166 GeV/c{sup 2} is excluded at the 95% C.L.
Date:
January 1, 2010
Creator:
Yamamoto, Kazuhiro & U., /Osaka City
Object Type:
Article
System:
The UNT Digital Library
High precision thermal stress study on flip chips by synchrotron polychromatic x-ray microdiffraction
The bending and residual stress of flip chips caused by the mismatch of thermal expansion between the chip and the substrate have been measured by polychromatic microfocused synchrotron x-ray beam. Precise orientation information as a function of position on the chip was obtained from Laue diffraction patterns, so that the bending angle with respect to a reference position at the center of the chip can be calculated at each position. This in turn allows deducing the local curvature of the entire flip chip. Local stress distribution was then mapped by applying a modified Stoney's stress-strain equation to the measured curvature. Our study shows that thermal stress on the circuits and the solder joints in a flip chip strongly depend on temperature and the distance from the center of the chip, indicating that interconnects at the corner and edge of a flip chip are of reliability concerns.
Date:
January 1, 2010
Creator:
Chen, Kai; Tamura, Nobumichi; Tang, Wei; Kunz, Martin; Chou, Yi-Chia; Tu, King-Ning et al.
Object Type:
Article
System:
The UNT Digital Library
How physics defines the LHC environment and detectors
None
Date:
January 1, 2010
Creator:
Green, D.
Object Type:
Article
System:
The UNT Digital Library
Hudspeth County Herald and Dell Valley Review (Dell City, Tex.), Vol. 54, No. 7, Ed. 1 Friday, January 1, 2010
Weekly newspaper from Dell City, Texas that includes local, state, and national news along with advertising.
Date:
January 1, 2010
Creator:
Stuart, Andrew
Object Type:
Newspaper
System:
The Portal to Texas History
Hydrogen Production: Fundamentals and Case Study Summaries; Preprint
This paper presents a detailed description of the chemical and electrical processes for electrolysis and fuel cells, discusses important terminology, units of measure, constants, and chemical reactions, and suggests recommendations for calculating electrolyzer and fuel cell performance.
Date:
January 1, 2010
Creator:
Harrison, K. W.; Remick, R.; Hoskin, A. & Martin, G. D.
Object Type:
Article
System:
The UNT Digital Library
Imaging doped silicon test structures using low energy electron microscopy.
This document is the final SAND Report for the LDRD Project 105877 - 'Novel Diagnostic for Advanced Measurements of Semiconductor Devices Exposed to Adverse Environments' - funded through the Nanoscience to Microsystems investment area. Along with the continuous decrease in the feature size of semiconductor device structures comes a growing need for inspection tools with high spatial resolution and high sample throughput. Ideally, such tools should be able to characterize both the surface morphology and local conductivity associated with the structures. The imaging capabilities and wide availability of scanning electron microscopes (SEMs) make them an obvious choice for imaging device structures. Dopant contrast from pn junctions using secondary electrons in the SEM was first reported in 1967 and more recently starting in the mid-1990s. However, the serial acquisition process associated with scanning techniques places limits on the sample throughput. Significantly improved throughput is possible with the use of a parallel imaging scheme such as that found in photoelectron emission microscopy (PEEM) and low energy electron microscopy (LEEM). The application of PEEM and LEEM to device structures relies on contrast mechanisms that distinguish differences in dopant type and concentration. Interestingly, one of the first applications of PEEM was a study of …
Date:
January 1, 2010
Creator:
Nakakura, Craig Yoshimi; Anderson, Meredith Lynn & Kellogg, Gary Lee
Object Type:
Report
System:
The UNT Digital Library
Impacts of Mixing on Acceptable Indoor Air Quality in Homes
Ventilation reduces occupant exposure to indoor contaminants by diluting or removing them. In a multi-zone environment such as a house, every zone will have different dilution rates and contaminant source strengths. The total ventilation rate is the most important factor in determining occupant exposure to given contaminant sources, but the zone-specific distribution of exhaust and supply air and the mixing of ventilation air can play significant roles. Different types of ventilation systems will provide different amounts of mixing depending on several factors such as air leakage, air distribution system, and contaminant source and occupant locations. Most U.S. and Canadian homes have central heating, ventilation, and air conditioning systems, which tend to mix the air; thus, the indoor air in different zones tends to be well mixed for significant fractions of the year. This article reports recent results of investigations to determine the impact of air mixing on exposures of residential occupants to prototypical contaminants of concern. We summarize existing literature and extend past analyses to determine the parameters than affect air mixing as well as the impacts of mixing on occupant exposure, and to draw conclusions that are relevant for standards development and for practitioners designing and installing home ventilation …
Date:
January 1, 2010
Creator:
Sherman, Max H. & Walker, Iain I.
Object Type:
Article
System:
The UNT Digital Library
Improving Biomass Yields: High Biomass, Low Input Dedicated Energy Crops to Enable a Full Scale Bioenergy Industry
Broad Funding Opportunity Announcement Project: Ceres is developing bigger and better grasses for use in biofuels. The bigger the grass yield, the more biomass, and more biomass means more biofuel per acre. Using biotechnology, Ceres is developing grasses that will grow bigger with less fertilizer than current grass varieties. Hardier, higher-yielding grass also requires less land to grow and can be planted in areas where other crops can’t grow instead of in prime agricultural land. Ceres is conducting multi-year trials in Arizona, Texas, Tennessee, and Georgia which have already resulted in grass yields with as much as 50% more biomass than yields from current grass varieties.
Date:
January 1, 2010
Creator:
unknown
Object Type:
Text
System:
The UNT Digital Library
In-Situ Measurements of Low Enrichment Uranium Holdup Process Gas Piping at K-25 - Paper for Waste Management Symposia 2010 East Tennessee Technology Park Oak Ridge, Tennessee
This document is the final version of a paper submitted to the Waste Management Symposia, Phoenix, 2010, abstract BJC/OR-3280. The primary document from which this paper was condensed is In-Situ Measurement of Low Enrichment Uranium Holdup in Process Gas Piping at K-25 Using NaI/HMS4 Gamma Detection Systems, BJC/OR-3355. This work explores the sufficiency and limitations of the Holdup Measurement System 4 (HJVIS4) software algorithms applied to measurements of low enriched uranium holdup in gaseous diffusion process gas piping. HMS4 has been used extensively during the decommissioning and demolition project of the K-25 building for U-235 holdup quantification. The HMS4 software is an integral part of one of the primary nondestructive assay (NDA) systems which was successfully tested and qualified for holdup deposit quantification in the process gas piping of the K-25 building. The initial qualification focused on the measurement of highly enriched UO{sub 2}F{sub 2} deposits. The purpose of this work was to determine if that qualification could be extended to include the quantification of holdup in UO{sub 2}F{sub 2} deposits of lower enrichment. Sample field data are presented to provide evidence in support of the theoretical foundation. The HMS4 algorithms were investigated in detail and found to sufficiently compensate …
Date:
January 1, 2010
Creator:
B., Rasmussen
Object Type:
Report
System:
The UNT Digital Library
Information technology and decision support tools for stakeholder-driven river basin salinity management
Innovative strategies for effective basin-scale salinity management have been developed in the Hunter River Basin of Australia and more recently in the San Joaquin River Basin of California. In both instances web-based stakeholder information dissemination has been a key to achieving a high level of stakeholder involvement and the formulation of effective decision support salinity management tools. A common element to implementation of salinity management strategies in both river basins has been the concept of river assimilative capacity for controlling export salt loading and the potential for trading of the right to discharge salt load to the river - the Hunter River in Australia and the San Joaquin River in California. Both rivers provide basin drainage and the means of exporting salt to the ocean. The paper compares and contrasts the use of monitoring, modeling and information dissemination in the two basins to achieve environmental compliance and sustain irrigated agriculture in an equitable and socially and politically acceptable manner.
Date:
January 1, 2010
Creator:
Quinn, Nigel W. T.; Cozad, Daniel B. & Lee, Gene
Object Type:
Article
System:
The UNT Digital Library
Integrating Primary Care Providers into Community Pandemic Influenza Planning Stakeholder Meeting - Meeting Proceedings
On August 24-26, 2009, a group of subject matter experts convened to begin work on developing tools for primary care provider offices.
Date:
January 1, 2010
Creator:
CHE, HCTT
Object Type:
Article
System:
The UNT Digital Library
International Clean Energy Analysis Gateway: Assisting Developing Countries with Clean Energy Deployment (Fact Sheet)
The International Clean Energy Analysis Gateway seeks to enhance developing country access to energy efficiency and renewable energy analysis tools, databases, methods, and other technical resources in a dynamic user interaction environment. In addition to providing information on available tools, the gateway also is a platform for Web seminars, online training, peer networks, and expert assistance. The gateway is sponsored by the U.S. Department of Energy (DOE) and the United Nations Industrial Development Organization (UNIDO) and managed by the National Renewable Energy Laboratory (NREL). Further cooperation is desired with organizations that can help expand the information presented in the portal and assist with outreach and training.
Date:
January 1, 2010
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Investigation of the carbon dioxide sorption capacity and structural deformation of coal
Due to increasing atmospheric CO2 concentrations causing the global energy and environmental crises, geological sequestration of carbon dioxide is now being actively considered as an attractive option to mitigate greenhouse gas emissions. One of the important strategies is to use deep unminable coal seams, for those generally contain significant quantities of coal bed methane that can be recovered by CO2 injection through enhanced coal bed natural gas production, as a method to safely store CO2. It has been well known that the adsorbing CO2 molecules introduce structural deformation, such as distortion, shrinkage, or swelling, of the adsorbent of coal organic matrix. The accurate investigations of CO2 sorption capacity as well as of adsorption behavior need to be performed under the conditions that coals deform. The U.S. Department of Energy-National Energy Technology Laboratory and Regional University Alliance are conducting carbon dioxide sorption isotherm experiments by using manometric analysis method for estimation of CO2 sorption capacity of various coal samples and are constructing a gravimetric apparatus which has a visual window cell. The gravimetric apparatus improves the accuracy of carbon dioxide sorption capacity and provides feasibility for the observation of structural deformation of coal sample while carbon dioxide molecules interact with coal …
Date:
January 1, 2010
Creator:
Hur, Tae-Bong; Fazio, James; Romanov, Vyacheslav & Harbert, William
Object Type:
Poster
System:
The UNT Digital Library
Investigations into the origins of polyatomic ions in inductively coupled plasma-mass spectrometry
An inductively coupled plasma-mass spectrometer (ICP-MS) is an elemental analytical instrument capable of determining nearly all elements in the periodic table at limits of detection in the parts per quadrillion and with a linear analytical range over 8-10 orders of magnitude. Three concentric quartz tubes make up the plasma torch. Argon gas is spiraled through the outer tube and generates the plasma powered by a looped load coil operating at 27.1 or 40.6 MHz. The argon flow of the middle channel is used to keep the plasma above the innermost tube through which solid or aqueous sample is carried in a third argon stream. A sample is progressively desolvated, atomized and ionized. The torch is operated at atmospheric pressure. To reach the reduced pressures of mass spectrometers, ions are extracted through a series of two, approximately one millimeter wide, circular apertures set in water cooled metal cones. The space between the cones is evacuated to approximately one torr. The space behind the second cone is pumped down to, or near to, the pressure needed for the mass spectrometer (MS). The first cone, called the sampler, is placed directly in the plasma plume and its position is adjusted to the point …
Date:
January 1, 2010
Creator:
McIntyre, Sally M.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Laser Interactions in Nanomaterials Synthesis
Laser interactions with materials have unique advantages to explore the rapid synthesis, processing, and in situ characterization of high quality and novel nanoparticles, nanotubes and nanowires. For example, laser vaporization of solids into background gases provides a wide range of processing conditions for the formation of nanomaterials by both catalyst-free and catalyst-assisted growth processes. Laser interactions with the growing nanomaterials provide remote in situ characterization of their size, structure, and composition with unprecedented temporal resolution. In this article, laser interactions involved in the synthesis of primarily carbon nanostructures are reviewed, including the catalyst-free synthesis of single-walled carbon nanohorns and quantum dots, to the catalyst-assisted growth of single and multi-walled carbon nanotubes.
Date:
January 1, 2010
Creator:
Geohegan, David B.; Puretzky, Alexander A.; Rouleau, Christopher M.; Jackson, Jeremy Joseph; Eres, Gyula; Xiao, Kai et al.
Object Type:
Book
System:
The UNT Digital Library
Latest results from the MINOS experiment
The MINOS experiment utilizes the NuMI neutrino beam to study the phenomenon of neutrino oscillations. Muon neutrinos are sent over a baseline of 735 km, with a detector near the production point at Fermilab and one at the Soudan underground laboratory in northern Minnesota. By observing the {nu}{sub {mu}} disappearance characteristic of oscillations, MINOS can measure the oscillation parameters. MINOS has previously made the best measurement of the atmospheric-regime mass splitting to date. New results are presented in which the data-set is doubled. Further analysis improvements, and the inclusion of additional event samples, further improve the sensitivity to the oscillation parameters. The mixing angle {theta}{sub 13} is currently not measured to differ from zero. By searching for {nu}{sub e} appearance in the {nu}{sub {mu}} beam, MINOS is able to set new limits on the value of {theta}{sub 13}. An observation of the neutral current interaction rate at the far detector allows limits to be placed on the existence of sterile neutrinos. From September 2009 to March 2010, MINOS has taken data with a dedicated {bar {nu}}{sub {mu}} beam, allowing the first direct precision measurement of the antineutrino oscillation parameters in the atmospheric regime.
Date:
January 1, 2010
Creator:
Evans, Justin & London, /University Coll.
Object Type:
Article
System:
The UNT Digital Library
Lightweight storage and overlay networks for fault tolerance.
The next generation of capability-class, massively parallel processing (MPP) systems is expected to have hundreds of thousands to millions of processors, In such environments, it is critical to have fault-tolerance mechanisms, including checkpoint/restart, that scale with the size of applications and the percentage of the system on which the applications execute. For application-driven, periodic checkpoint operations, the state-of-the-art does not provide a scalable solution. For example, on today's massive-scale systems that execute applications which consume most of the memory of the employed compute nodes, checkpoint operations generate I/O that consumes nearly 80% of the total I/O usage. Motivated by this observation, this project aims to improve I/O performance for application-directed checkpoints through the use of lightweight storage architectures and overlay networks. Lightweight storage provide direct access to underlying storage devices. Overlay networks provide caching and processing capabilities in the compute-node fabric. The combination has potential to signifcantly reduce I/O overhead for large-scale applications. This report describes our combined efforts to model and understand overheads for application-directed checkpoints, as well as implementation and performance analysis of a checkpoint service that uses available compute nodes as a network cache for checkpoint operations.
Date:
January 1, 2010
Creator:
Oldfield, Ron A.
Object Type:
Report
System:
The UNT Digital Library
Limitations on the predictions for p(T)-balance in events with a Z-boson and jets
We investigate the impact of theoretical uncertainties on the accuracy of measurements involving hadronic jets. The analysis is performed using events with a Z boson and a single jet observed in p {bar p} collisions at {radical}s = 1.96 TeV in 4.6 fb{sup -1} of data from the Collider Detector at Fermilab (CDF). The transverse momenta (p{sub T}) of the jet and the boson should balance each other due to momentum conservation in the plane transverse to the direction of the p and {bar p} beams. We evaluate the dependence of the measured p{sub T}-balance on theoretical uncertainties associated with initial and final state radiation, choice of renormalization and factorization scales, parton distribution functions, jet-parton matching, calculations of matrix elements, and parton showering. We find that the uncertainty caused by parton showering at large angles is the largest among the listed uncertainties. The proposed method can be re-applied at the LHC experiments to investigate and evaluate the uncertainties on the predicted jet energies. The distributions produced at the CDF environment are intended for comparison to those from modern event generators and new tunes of parton showering. The comparison will allow higher accuracy of the predicted jet energies, and thus an …
Date:
January 1, 2010
Creator:
Paramonov, Alexander A.
Object Type:
Article
System:
The UNT Digital Library
Linux OS Jitter Measurements at Large Node Counts using a BlueGene/L
We present experimental results for a coordinated scheduling implementation of the Linux operating system. Results were collected on an IBM Blue Gene/L machine at scales up to 16K nodes. Our results indicate coordinated scheduling was able to provide a dramatic improvement in scaling performance for two applications characterized as bulk synchronous parallel programs.
Date:
January 1, 2010
Creator:
Jones, Terry R; Tauferner, Mr. Andrew & Inglett, Mr. Todd
Object Type:
Report
System:
The UNT Digital Library
Long-Range Electric Vehicle Batteries: High Energy Density Lithium Batteries
Broad Funding Opportunity Announcement Project: In a battery, metal ions move between the electrodes through the electrolyte in order to store energy. Envia Systems is developing new silicon-based negative electrode materials for Li-Ion batteries. Using this technology, Envia will be able to produce commercial EV batteries that outperform today’s technology by 2-3 times. Many other programs have attempted to make anode materials based on silicon, but have not been able to produce materials that can withstand charge/discharge cycles multiple times. Envia has been able to make this material which can successfully cycle hundreds of times, on a scale that is economically viable. Today, Envia’s batteries exhibit world-record energy densities.
Date:
January 1, 2010
Creator:
unknown
Object Type:
Text
System:
The UNT Digital Library
Low-Cost Flexible Electrochromic Film for Energy Efficient Buildings
Broad Funding Opportunity Announcement Project: ITN is addressing the high cost of electrochromic windows with a new manufacturing process: roll-to-roll deposition of the film onto flexible plastic surfaces. Production of electrochromic films on plastic requires low processing temperatures and uniform film quality over large surface areas. ITN is overcoming these challenges using its previous experience in growing flexible thin-film solar cells and batteries. By developing sensor-based controls, ITN’s roll-to-roll manufacturing process yields more film over a larger area than traditional film deposition methods. Evaluating deposition processes from a control standpoint ultimately strengthens the ability for ITN to handle unanticipated deviations quickly and efficiently, enabling more consistent large-volume production. The team is currently moving from small-scale prototypes into pilot-scale production to validate roll-to-roll manufacturability and produce scaled prototypes that can be proven in simulated operating conditions. Electrochromic plastic films could also open new markets in building retrofit applications, vastly expanding the potential energy savings.
Date:
January 1, 2010
Creator:
unknown
Object Type:
Text
System:
The UNT Digital Library
Measurement of Interfacial Area Production and Permeability within Porous Media
An understanding of the pore-level interactions that affect multi-phase flow in porous media is important in many subsurface engineering applications, including enhanced oil recovery, remediation of dense non-aqueous liquid contaminated sites, and geologic CO2 sequestration. Standard models of two-phase flow in porous media have been shown to have several shortcomings, which might partially be overcome using a recently developed model based on thermodynamic principles that includes interfacial area as an additional parameter. A few static experimental studies have been previously performed, which allowed the determination of static parameters of the model, but no information exists concerning the interfacial area dynamic parameters. A new experimental porous flow cell that was constructed using stereolithography for two-phase gas-liquid flow studies was used in conjunction with an in-house analysis code to provide information on dynamic evolution of both fluid phases and gas-liquid interfaces. In this paper, we give a brief introduction to the new generalized model of two-phase flow model and describe how the stereolithography flow cell experimental setup was used to obtain the dynamic parameters for the interfacial area numerical model. In particular, the methods used to determine the interfacial area permeability and production terms are shown.
Date:
January 1, 2010
Creator:
Crandall, Dustin; Ahmadi, Goodarz & Smith, Duane H.
Object Type:
Article
System:
The UNT Digital Library
Measurement of the inclusive forward-backward t$\bar{t}$ production asymmetry and its rapidity dependence dA<sub>fb</sub>/d(Δy)
Early measurements of a large forward-background asymmetry at the CDF and D0 experiments at Fermilab have generated much recent interest, but were hampered by large uncertainties. We present here a new measurement of the parton level forward-backward asymmetry of pair-produced top quarks, using a high-statistics sample with much improved precision. We study the rapidity, y<sub>top</sub>, of the top quark production angle with respect to the incoming parton momentum in both the lab and t$\bar{t}$ rest frames. We find the parton-level forward-backward asymmetries to be A<sub>fb</sub><sup>p$\bar{t}$</sup> = 0.150 ± 0.050<sup>stat</sup> ± 0.024<sup>syst</sup> A<sub>fb</sub><sup>t$\bar{t}$</sup> = 0.158 ± 0.072{sup stat} ± 0.024<sup>syst</sup>. These results should be compared with the small p$\bar{p}$ frame charge asymmetry expected in QCD at NLO, A<sub>fb</sub> = 0.050 ± 0.015. Additionally, we introduce a measurement of the A<sub>fb</sub> rapidity dependence dA<sub>fb</sub>/d(Δy). We find this to be A<sub>fb</sub><sup>p$\bar{t}$</sup>(|Δy| < 1.0) = 0.026 ± 0.104<sup>stat</sup> ± 0.012 <sup>syst</sup> A<sub>fb</sub><sup>p$\bar{t}$</sup>(|Δy| > 1.0) = 0.611 ± 0.210<sup>stat</sup> ± 0.246<sup>syst</sup> which we compare with model predictions 0.039 ± 0.006 and 0.123 ± 0.018 for the inner and outer rapidities, respectively.
Date:
January 1, 2010
Creator:
Strycker, Glenn Loyd
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library