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Cost-Effective Silicon Wafers for Solar Cells (open access)

Cost-Effective Silicon Wafers for Solar Cells

Advanced Research Projects Agency-Energy project sheet summarizing general information about a new program for hydrogen fuel cell vehicles (project title "Direct Wafer Enabling Terawatt Photovoltaics") including critical needs, innovation and advantages, impacts, and contact information. This sheet is the first open solicitation, announcing funding opportunities for involvement in the project.
Date: May 11, 2012
Creator: 1366 Technologies, Inc.
Object Type: Text
System: The UNT Digital Library
Local Effects of Biased Electrodes in the Divertor of NSTX (open access)

Local Effects of Biased Electrodes in the Divertor of NSTX

The goal of this paper is to characterize the effects of small non-axisymmetric divertor plate electrodes on the local scrape-off layer plasma. Four small rectangular electrodes were installed into the outer divertor plates of NSTX. When the electrodes were located near the outer divertor strike point and biased positively, there was an increase in the nearby probe currents and probe potentials and an increase in the LiI light emission at the large major radius end of these electrodes. When an electrode located farther outward from the outer divertor strike point was biased positively, there was sometimes a significant decrease in the LiI light emission at the small major radius end of this electrode, but there were no clear effects on the nearby probes. No non-local effects were observed with the biasing of these electrodes.
Date: May 7, 2012
Creator: : S. Zweben, M.D. Campanell, B.C. Lyons, R.J. Maqueda, Y. Raitses, A.L. Roquemore and F. Scotti
Object Type: Report
System: The UNT Digital Library
Analysis of Vernier Scans during the PP2PP run in 2009 (pp at 100 GeV/beam) (open access)

Analysis of Vernier Scans during the PP2PP run in 2009 (pp at 100 GeV/beam)

N/A
Date: May 1, 2012
Creator: A., Drees
Object Type: Report
System: The UNT Digital Library
Shielding of a hadron in a finite e-beam (open access)

Shielding of a hadron in a finite e-beam

The thorough study of coherent electron cooling, the modern cooling technique capable to deal with accelerators operating in the range of few TeVs, rises many interesting questions. One of them is a shielding dynamics of a hadron in an electron beam. Now this effect is computed analytically in the infinite beam approximation. Many effects are drastically different in finite and infinite plasmas. Here we propose a method to compute the dynamical shielding effect in a finite cylindrical plasma - the realistic model of an electron beam in accelerators.
Date: May 20, 2012
Creator: A., Elizarov; Litvinenko, V. & Wang, G.
Object Type: Article
System: The UNT Digital Library
Towards demonstration of electron cooling with bunched electron beam (open access)

Towards demonstration of electron cooling with bunched electron beam

N/A
Date: May 1, 2012
Creator: A., Fedotov
Object Type: Report
System: The UNT Digital Library
Optics modification of the electron collector for the Relativistic Heavy Ion Collider Electron Beam Ion Source (open access)

Optics modification of the electron collector for the Relativistic Heavy Ion Collider Electron Beam Ion Source

N/A
Date: May 1, 2012
Creator: A., Pikin; Alessi, J.G.; Beebe, E.N.; Raparia, D. & Snydstrup, L.
Object Type: Report
System: The UNT Digital Library
Optics modification of the electron collector for the Relativistic Heavy Ion Collider Electron Beam Ion Source (open access)

Optics modification of the electron collector for the Relativistic Heavy Ion Collider Electron Beam Ion Source

N/A
Date: May 1, 2012
Creator: A., Pikin; Alessi, J.G.; Beebe, E.N.; Raparia, D. & Snydstrup, L.
Object Type: Report
System: The UNT Digital Library
Porosity in millimeter-scale welds of stainless steel : three-dimensional characterization. (open access)

Porosity in millimeter-scale welds of stainless steel : three-dimensional characterization.

A variety of edge joints utilizing a continuous wave Nd:YAG laser have been produced and examined in a 304-L stainless steel to advance fundamental understanding of the linkage between processing and resultant microstructure in high-rate solidification events. Acquisition of three-dimensional reconstructions via micro-computed tomography combined with traditional metallography has allowed for qualitative and quantitative characterization of weld joints in a material system of wide use and broad applicability. The presence, variability and distribution of porosity, has been examined for average values, spatial distributions and morphology and then related back to fundamental processing parameters such as weld speed, weld power and laser focal length.
Date: May 1, 2012
Creator: Aagesen, Larry K. & Madison, Jonathan D.
Object Type: Report
System: The UNT Digital Library
$W$ boson polarization measurement in the $t\bar{t}$ dilepton channel using the CDF II Detector (open access)

$W$ boson polarization measurement in the $t\bar{t}$ dilepton channel using the CDF II Detector

We present a measurement of W boson polarization in top-quark decays in t{bar t} events with decays to dilepton final states using 5.1 fb{sup -1} integrated luminosity in p{bar p} collisions collected by the CDF II detector at the Tevatron. A simultaneous measurement of the fractions of longitudinal (f{sub 0}) and right-handed (f{sub +}) W bosons yields the results f{sub 0} = 0.71{sub -0.17}{sup +0.18}(stat) {+-} 0.06(syst) and f{sub +} = -0.07 {+-} 0.09(stat) {+-} 0.03(syst). Combining this measurement with our previous result based on single lepton final states, we obtain f{sub 0} = 0.84 {+-} 0.09(stat) {+-} 0.05(syst) and f{sub +} = -0.16 {+-} 0.05(stat) {+-} 0.04(syst). The results are consistent with standard model expectation.
Date: May 1, 2012
Creator: Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the Cosmic Ray e+ plus e- Spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope (open access)

Measurement of the Cosmic Ray e+ plus e- Spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope

Designed as a high-sensitivity gamma-ray observatory, the Fermi Large Area Telescope is also an electron detector with a large acceptance exceeding 2 m{sup 2}sr at 300 GeV. Building on the gamma-ray analysis, we have developed an efficient electron detection strategy which provides sufficient background rejection for measurement of the steeply-falling electron spectrum up to 1 TeV. Our high precision data show that the electron spectrum falls with energy as E{sup -3.0} and does not exhibit prominent spectral features. Interpretations in terms of a conventional diffusive model as well as a potential local extra component are briefly discussed.
Date: May 14, 2012
Creator: Abdo, Aous A.; /Naval Research Lab, Wash., D.C.; Ackermann, M.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Ajello, M.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. et al.
Object Type: Article
System: The UNT Digital Library
Conversion Tower for Dispatchable Solar Power (open access)

Conversion Tower for Dispatchable Solar Power

Advanced Research Projects Agency-Energy project sheet summarizing general information about the High Energy Advanced Thermal Storage (HEATS) program including critical needs, innovation and advantages, impacts, and contact information. This sheet discusses new system architecture for a solar-electric conversion tower as part of the "High-Efficiency Solar-Electric Conversion Power Tower" project.
Date: May 25, 2012
Creator: Abengoa Solar, Inc.
Object Type: Text
System: The UNT Digital Library
A METHODOLOGY FOR DETERMINING THE DOSE RATE FOR BOUNDING MASS LIMITS IN A 9977 PACKAGING (open access)

A METHODOLOGY FOR DETERMINING THE DOSE RATE FOR BOUNDING MASS LIMITS IN A 9977 PACKAGING

The Small Gram Quantity (SGQ) concept is based on the understanding that the hazards associated with the shipment of a radioactive material are directly proportional to its mass. This study describes a methodology that estimates the acceptable masses for several neutron and gamma emitting isotopes that can be shipped in a 9977 Package compliant with the Title 10 of the Code of Federal Regulations, Part 71 (10CFR71) external radiation level limits. 10CFR71.33 states that a shipping application identifies the radioactive and fissile materials at their maximum quantity and provides an evaluation demonstrating compliance with the external radiation standards. Since rather small amounts of some isotopes emit sufficiently strong radiation to produce a large external dose rate, quantifying of the dose rate for a proposed content is a challenging issue for the SGQ approach. It is essential to quantify external radiation levels from several common gamma and neutron sources that can be safely placed in a specific packaging, to ensure compliance with federal regulations. A methodology was established for determining the dose rate for bounding mass limits for a set of isotopes in the Model 9977 Shipping Package. Calculations were performed to estimate external radiation levels using the MCNP radiation transport …
Date: May 24, 2012
Creator: Abramczyk, G.; Bellamy, S.; Nathan, S. & Loftin, B.
Object Type: Article
System: The UNT Digital Library

Unified Digital Format Registry (UDFR) Understanding the System and Service

Presentation for the 2012 International Internet Preservation Consortium General Assembly. Slides for a workshop about the Unified Digital Format Registry (UDFR) service.
Date: May 4, 2012
Creator: Abrams, Stephen; Colvin, Lisa Dawn & Salve, Abhishek
Object Type: Presentation
System: The UNT Digital Library
Fish Health Studies Associated with the Kingston Fly Ash Spill, Spring 2009 - Fall 2010 (open access)

Fish Health Studies Associated with the Kingston Fly Ash Spill, Spring 2009 - Fall 2010

On December 22, 2008, over 4 million cubic meters of fly ash slurry was released into the Emory River when a dike surrounding a solid waste containment area at the Tennessee Valley Authority's (TVA) Kingston Fossil Plant ruptured. One component of TVA's response to the spill is a biological monitoring program to assess short- and long-term ecological responses to the ash and associated chemicals, including studies on fish health and contaminant bioaccumulation. These studies were initiated in early Spring 2009 for the purposes of: (1) documenting the levels of fly ash-associated metals in various tissues of representative sentinel fish species in the area of the fly ash spill, (2) determining if exposure to fly ash-associated metals causes short, intermediate, or long-term health effects on these sentinel fish species, (3) assessing if there are causal relationships between exposure to metals and health effects on fish, (4) evaluating, along with information from other ecological and physicochemical studies, the nature and route of contaminant transfer though food chains into higher level consumers, (5) providing important information for the Ecological Risk Assessment (ERA) for the Kingston fly ash project, and (6) serving as an important technology information transfer or model study focused on how …
Date: May 1, 2012
Creator: Adams, Marshall & Fortner, Allison M
Object Type: Report
System: The UNT Digital Library
Bioaccumulation Studies Associated with the Kingston Fly Ash Spill, Spring 2009 - Fall 2010 (open access)

Bioaccumulation Studies Associated with the Kingston Fly Ash Spill, Spring 2009 - Fall 2010

In December 2008, an ash dike at the Tennessee Valley Authority (TVA) Kingston Fossil Plant ruptured, releasing over one billion gallons of coal fly ash into the Emory and Clinch Rivers. Coal fly ash may contain several contaminants of concern, but of these selenium (Se) and arsenic (As) have been highlighted because of their toxicity and tendency to bioaccumulate in aquatic food chains. To assess the potential impact of the spilled fly ash on humans and the environment, a comprehensive biological and environmental monitoring program was established, for which resident aquatic organisms (among other sample media) are collected to determine contaminant exposure and evaluate the risk to humans and wildlife. Studies on bioaccumulation and fish health are major components of the TVA Biological Monitoring Program for the Kingston fly ash project. These studies were initiated in early Spring 2009 for the purposes of: (1) documenting the levels of fly ash-associated metals in various tissues of representative sentinel fish species in the area of the fly ash spill, (2) determining if exposure to fly ash-associated metals causes short, intermediate, or long-term health effects on these sentinel fish species, (3) assessing if there are causal relationships between exposure (to metals) and effects …
Date: May 1, 2012
Creator: Adams, Marshall; Brandt, Craig C & Fortner, Allison M
Object Type: Report
System: The UNT Digital Library
METAL MEDIA FILTERS, AG-1 SECTION FI (open access)

METAL MEDIA FILTERS, AG-1 SECTION FI

One application of metal media filters is in various nuclear air cleaning processes including applications for protecting workers, the public and the environment from hazardous and radioactive particles. To support this application the development of the ASME AG-1 FI Standard on Metal Media has been under way for more than ten years. Development of the proposed section has required resolving several difficult issues associated with operating conditions (media velocity, pressure drop, etc.), qualification testing, and quality acceptance testing. Performance characteristics of metal media are dramatically different than the glass fiber media with respect to parameters like differential pressures, operating temperatures, media strength, etc. These differences make existing data for a glass fiber media inadequate for qualifying a metal media filter for AG-1. In the past much work has been conducted on metal media filters at facilities such as Lawrence Livermore National Laboratory (LLNL) and Savannah River National Laboratory (SRNL) to qualify the media as High Efficiency Particulate Air (HEPA) Filters. Particle retention testing has been conducted at Oak Ridge Filter Test Facility and at Air Techniques International (ATI) to prove that the metal media meets or exceeds the 99.97% particle retention required for a HEPA Filter. Even with his testing, …
Date: May 23, 2012
Creator: Adamson, D.
Object Type: Article
System: The UNT Digital Library
Oral History Interview with Al Adkins, May 25, 2012 transcript

Oral History Interview with Al Adkins, May 25, 2012

The National Museum of the Pacific War presents an interview with Al Adkins. Adkins joined the Marine Corps in the fall of 1942. He served with the 6th Marine Division, 22nd Marine Regiment. They participated in the Battle of Eniwetok in the Marshall Islands. On Guadalcanal, they formed the 1st Provisional Marine Brigade, participating in the Battle of Guam until they disbanded in September of 1944. Continuing on with the 22nd Marines, Adkins served in the Battle of Okinawa. He returned to the US and received his discharge in September of 1945.
Date: May 25, 2012
Creator: Adkins, Al
Object Type: Sound
System: The Portal to Texas History
Oral History Interview with Al Adkins, May 25, 2012 (open access)

Oral History Interview with Al Adkins, May 25, 2012

The National Museum of the Pacific War presents an interview with Al Adkins. Adkins joined the Marine Corps in the fall of 1942. He served with the 6th Marine Division, 22nd Marine Regiment. They participated in the Battle of Eniwetok in the Marshall Islands. On Guadalcanal, they formed the 1st Provisional Marine Brigade, participating in the Battle of Guam until they disbanded in September of 1944. Continuing on with the 22nd Marines, Adkins served in the Battle of Okinawa. He returned to the US and received his discharge in September of 1945.
Date: May 25, 2012
Creator: Adkins, Al
Object Type: Text
System: The Portal to Texas History
LITERATURE REVIEW ON IMPACT OF GLYCOLATE ON THE 2H EVAPORATOR AND THE EFFLUENT TREATMENT FACILITY (open access)

LITERATURE REVIEW ON IMPACT OF GLYCOLATE ON THE 2H EVAPORATOR AND THE EFFLUENT TREATMENT FACILITY

Glycolic acid (GA) is being studied as an alternate reductant in the Defense Waste Processing Facility (DWPF) feed preparation process. It will either be a total or partial replacement for the formic acid that is currently used. A literature review has been conducted on the impact of glycolate on two post-DWPF downstream systems - the 2H Evaporator system and the Effluent Treatment Facility (ETF). The DWPF recycle stream serves as a portion of the feed to the 2H Evaporator. Glycolate enters the evaporator system from the glycolate in the recycle stream. The overhead (i.e., condensed phase) from the 2H Evaporator serves as a portion of the feed to the ETF. The literature search revealed that virtually no impact is anticipated for the 2H Evaporator. Glycolate may help reduce scale formation in the evaporator due to its high complexing ability. The drawback of the solubilizing ability is the potential impact on the criticality analysis of the 2H Evaporator system. It is recommended that at least a theoretical evaluation to confirm the finding that no self-propagating violent reactions with nitrate/nitrites will occur should be performed. Similarly, identification of sources of ignition relevant to glycolate and/or update of the composite flammability analysis to …
Date: May 10, 2012
Creator: Adu-Wusu, K.
Object Type: Report
System: The UNT Digital Library
Engineering Enzymes in Energy Crops (open access)

Engineering Enzymes in Energy Crops

Advanced Research Projects Agency-Energy project sheet summarizing general information about a new program to engineer plants to produce enzymes that will reduce costs in the production of biofuel (project title "Conditionally Activated Enzymes Expressed in Cellulosic Energy Crops") including critical needs, innovation and advantages, impacts, and contact information. This sheet is the first open solicitation, announcing funding opportunities for involvement in the project.
Date: May 11, 2012
Creator: Agrivdia
Object Type: Text
System: The UNT Digital Library
Interpersonal Factors Related to the Pursuit of a Higher Education Among First Generation Undergraduate Students (open access)

Interpersonal Factors Related to the Pursuit of a Higher Education Among First Generation Undergraduate Students

The typical educational stressors experienced by college students, in conjunction with developmental stressors such as separation from parents, individuation, and perceived social support, can interact to impact adaptation significantly. First generation college students (students who are the first in their family to attend college) can experience stressors beyond the typical educational stressors experienced by later generation college students, including lack of support from family and peers as well as financial difficulties that can interact to impact the pursuit of an education beyond the undergraduate level. The present study examined factors that may be especially influential in the pursuit of a higher education for first generation college students. Results indicated that aspects of family enmeshment were related to academic motivation for first generation students, but not for later generation students. Exploratory analysis showed that family and finances were mentioned more often among first generation students when compared to later generation students as stressors that strongly influence the desire to continue beyond the undergraduate level.
Date: May 2012
Creator: Aguirre, Jacqueline S.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
General Satisfaction of Students in 100% Online Courses in the Department of Learning Technologies at the University of North Texas (open access)

General Satisfaction of Students in 100% Online Courses in the Department of Learning Technologies at the University of North Texas

The purpose of this study was to examine whether there are significant relationships between the general satisfaction of students and learner-content interaction, learner-instructor interaction, learner-learner interaction, and learner-technology interaction in 100% online courses. There were 310 responses from the students. This study did not use data from duplicate students and instructors. Excel was used to find duplicate students and instructors; therefore, 128 responses were deleted. After examination of box plots, an additional four cases were removed because they were outliers on seven or more variables. Nineteen responses were deleted because they did not answer all questions of interest, resulting in a total sample of 159 students. Multiple regression analysis was used to examine the relationship between the four independent variables and the dependent variable. In addition to tests for statistical significance, practical significance was evaluated with the multiple R2 , which reported the common variance between independent variables and dependent variable. The two variables of learner-content and learner-instructor interaction play a significant role in predicting online satisfaction. Minimally, the variable learner-technology can predict online satisfaction and is an important construct that must be considered when offering online courses. Results of this study provide help in establishing a valid and reliable …
Date: May 2012
Creator: Ahn, Byungmun
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Lifecycle Management of ETDs: Toward A Collaborative Approach To Stakeholders' Involvement In ETDs Curation

This presentation discusses the management and curation of Electronic Theses and Dissertations (ETDs). It highlights and discusses the early findings of an IMLS-funded project on Lifecycle Management of ETDs.
Date: May 2012
Creator: Alemneh, Daniel Gelaw; Henry, Geneva & Stark, Shannon
Object Type: Presentation
System: The UNT Digital Library

"Mapping the Southwest": UNT-UTA Collaborative Project

This presentation discusses a collaborative project between the University of North Texas (UNT) and the University of Texas at Arlington (UTA) to digitize 5,000 historically-significant, rare maps of the American southwest.
Date: May 2012
Creator: Alemneh, Daniel Gelaw; Jones, Jerrell & Hodges, Ann
Object Type: Presentation
System: The UNT Digital Library