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ELECTRON BEAM ION SOURCE PREINJECTOR PROJECT (EBIS) CONCEPTUAL DESIGN REPORT. (open access)

ELECTRON BEAM ION SOURCE PREINJECTOR PROJECT (EBIS) CONCEPTUAL DESIGN REPORT.

This report describes a new heavy ion pre-injector for the Relativistic Heavy Ion Collider (RHIC) based on a high charge state Electron Beam Ion Source (EBIS), a Radio Frequency Quadrupole (RFQ) accelerator, and a short Linac. The highly successful development of an EBIS at BNL now makes it possible to replace the present pre-injector that is based on an electrostatic Tandem with a reliable, low maintenance Linac-based pre-injector. Linac-based pre-injectors are presently used at most accelerator and collider facilities with the exception of RHIC, where the required gold beam intensities could only be met with a Tandem until the recent EBIS development. EBIS produces high charge state ions directly, eliminating the need for the two stripping foils presently used with the Tandem. Unstable stripping efficiencies of these foils are a significant source of luminosity degradation in RHIC. The high reliability and flexibility of the new Linac-based pre-injector will lead to increased integrated luminosity at RHIC and is an essential component for the long-term success of the RHIC facility. This new pre-injector, based on an EBIS, also has the potential for significant future intensity increases and can produce heavy ion beams of all species including uranium beams and, as part of …
Date: February 28, 2005
Creator: ALESSI, J.; BARTON, D.; BEEBE, E.; GASSNER, D. & AL., ET
Object Type: Report
System: The UNT Digital Library
An Order-of-Magnitude Estimation of Benzene Concentration in Saltstone Vault (open access)

An Order-of-Magnitude Estimation of Benzene Concentration in Saltstone Vault

The contents of Tank 48 that include the tetraphenylborate (TPB) precipitates of potassium and cesium will be grouted and stored in the Saltstone vault. The grouting process is exothermic, which should accelerate the decomposition of TPB precipitates eventually to benzene. Because the vault is not currently outfitted with an active ventilation system, there is a concern that a mixture of flammable gases may form in the vapor space of each cell filled with the curing grout. The purpose of this study was to determine if passive breathing induced by the diurnal oscillations of atmospheric pressure would provide any mitigating measure against potential flammability. Specifically, it was requested that a set of algorithms be developed that would predict the equilibrium concentration of benzene as a function of benzene generation rate, fill height, and the amplitude of the barometric pressure oscillations. These algorithms were to be derived based on several simplifying assumptions so that order of magnitude estimates could be made quickly for scoping purposes. This memo documents the resulting algorithms along with those key assumptions made. These algorithms were then applied to simulate several test cases, including the baseline case where the cell was filled to the maximum height of 25 …
Date: February 28, 2005
Creator: ALEXANDER, CHOI
Object Type: Report
System: The UNT Digital Library
Evaluation of Ultra Clean Fuels from Natural Gas (open access)

Evaluation of Ultra Clean Fuels from Natural Gas

ConocoPhillips, in conjunction with Nexant Inc., Penn State University, and Cummins Engine Co., joined with the U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) in a cooperative agreement to perform a comprehensive study of new ultra clean fuels (UCFs) produced from remote sources of natural gas. The project study consists of three primary tasks: an environmental Life Cycle Assessment (LCA), a Market Study, and a series of Engine Tests to evaluate the potential markets for Ultra Clean Fuels. The overall objective of DOE's Ultra Clean Transportation Fuels Initiative is to develop and deploy technologies that will produce ultra-clean burning transportation fuels for the 21st century from both petroleum and non-petroleum resources. These fuels will: (1) Enable vehicles to comply with future emission requirements; (2) Be compatible with the existing liquid fuels infrastructure; (3) Enable vehicle efficiencies to be significantly increased, with concomitantly reduced CO{sub 2} emissions; (4) Be obtainable from a fossil resource, alone or in combination with other hydrocarbon materials such as refinery wastes, municipal wastes, biomass, and coal; and (5) Be competitive with current petroleum fuels. The objectives of the ConocoPhillips Ultra Clean Fuels Project are to perform a comprehensive life cycle analysis and to conduct …
Date: February 28, 2006
Creator: Abbott, Robert; Casey, Edward; Esen, Etop; Smith, Douglas; Burke, Bruce; Nguyen, Binh et al.
Object Type: Report
System: The UNT Digital Library
Nuclear Energy Research Initiative Project No. 02 103 Innovative Low Cost Approaches to Automating QA/QC of Fuel Particle Production Using On Line Nondestructive Methods for Higher Reliability Final Project Report (open access)

Nuclear Energy Research Initiative Project No. 02 103 Innovative Low Cost Approaches to Automating QA/QC of Fuel Particle Production Using On Line Nondestructive Methods for Higher Reliability Final Project Report

This Nuclear Energy Research Initiative (NERI) project was tasked with exploring, adapting, developing and demonstrating innovative nondestructive test methods to automate nuclear coated particle fuel inspection so as to provide the United States (US) with necessary improved and economical Quality Assurance and Control (QA/QC) that is needed for the fuels for several reactor concepts being proposed for both near term deployment [DOE NE & NERAC, 2001] and Generation IV nuclear systems. Replacing present day QA/QC methods, done manually and in many cases destructively, with higher speed automated nondestructive methods will make fuel production for advanced reactors economically feasible. For successful deployment of next generation reactors that employ particle fuels, or fuels in the form of pebbles based on particles, extremely large numbers of fuel particles will require inspection at throughput rates that do not significantly impact the proposed manufacturing processes. The focus of the project is nondestructive examination (NDE) technologies that can be automated for production speeds and make either: (I) On Process Measurements or (II) In Line Measurements. The inspection technologies selected will enable particle “quality” qualification as a particle or group of particles passes a sensor. A multiple attribute dependent signature will be measured and used for qualification …
Date: February 28, 2006
Creator: Ahmed, Salahuddin; Batishko, Charles R.; Flake, Matthew; Good, Morris S.; Mathews, Royce; Morra, Marino et al.
Object Type: Report
System: The UNT Digital Library
The Grand Challenge of Managing the Petascale Facility. (open access)

The Grand Challenge of Managing the Petascale Facility.

This report is the result of a study of networks and how they may need to evolve to support petascale leadership computing and science. As Dr. Ray Orbach, director of the Department of Energy's Office of Science, says in the spring 2006 issue of SciDAC Review, 'One remarkable example of growth in unexpected directions has been in high-end computation'. In the same article Dr. Michael Strayer states, 'Moore's law suggests that before the end of the next cycle of SciDAC, we shall see petaflop computers'. Given the Office of Science's strong leadership and support for petascale computing and facilities, we should expect to see petaflop computers in operation in support of science before the end of the decade, and DOE/SC Advanced Scientific Computing Research programs are focused on making this a reality. This study took its lead from this strong focus on petascale computing and the networks required to support such facilities, but it grew to include almost all aspects of the DOE/SC petascale computational and experimental science facilities, all of which will face daunting challenges in managing and analyzing the voluminous amounts of data expected. In addition, trends indicate the increased coupling of unique experimental facilities with computational facilities, …
Date: February 28, 2007
Creator: Aiken, R. J. & Science, Mathematics and Computer
Object Type: Report
System: The UNT Digital Library
Characterizing the fabric of the urban environment: A case study of Salt Lake City, Utah (open access)

Characterizing the fabric of the urban environment: A case study of Salt Lake City, Utah

Urban fabric data are needed in order to estimate the impact of light-colored surfaces (roofs and pavements) and urban vegetation (trees, grass, shrubs) on the meteorology and air quality of a city, and to design effective implementation programs. In this report, we discuss the result of a semi-automatic Monte-Carlo statistical approach used to develop data on surface-type distribution and city-fabric makeup (percentage of various surface-types) using aerial color orthophotography. The digital aerial photographs for Salt Lake City covered a total of about 34 km2 (13 mi2). At 0.50-m resolution, there were approximately 1.4 x 108 pixels of data. Four major land-use types were examined: (1) commercial, (2) industrial, (3) educational, and (4) residential. On average, for the areas studied, vegetation covers about 46 percent of the area (ranging 44-51 percent), roofs cover about 21 percent (ranging 15-24 percent), and paved surfaces about 26 percent (ranging 21-28 percent). For the most part, trees shade streets, parking lots, grass, and sidewalks. In most non-residential areas, paved surfaces cover 46-66 percent of the area. In residential areas, on average, paved surfaces cover about 32 percent of the area. Land-use/land-cover (LU/LC) data from the United States Geological Survey were used to extrapolate these results …
Date: February 28, 2001
Creator: Akbari, Hashem & Rose, L. Shea
Object Type: Report
System: The UNT Digital Library
Radiation dose measurements of the insertion devices (open access)

Radiation dose measurements of the insertion devices

None
Date: February 28, 2002
Creator: Alderman, J & Job, P. K.
Object Type: Report
System: The UNT Digital Library
Radiation dose measurements of the insertion devices (open access)

Radiation dose measurements of the insertion devices

The Advanced Photon Source (APS) uses Nd-Fe-B permanent magnets in the insertion devices to produce x-rays for scientific research. Earlier investigations have exhibited varying degrees of demagnetization of these magnets due to irradiation from electron beams, {sup 60}Co {gamma}-rays, and high-energy neutrons. Although no detectable radiation-induced demagnetization has been observed in the APS insertion devices so far, partial demagnetization has been observed in at lest one insertion device at the European Synchrotron Radiation Facility (ESRF), where Nd-Fe-B permanent magnets are also used. A growing concern for the APS insertion devices, as well as the permanent magnets that will be used in next generation high-power light sources, like the FEL, resulted from the partial demagnetization observed in the ESRF devices. This concern in relation to radiation-induced demagnetization spurred a long-term project aimed to measure and analyze the total absorbed doses received by the APS insertion devices. The project required a reliable photon high dose dosimetry technique capable of measuring absorbed doses greater than 10{sup 6} rad, which was not readily available at the APS. Through a collaboration with the National Institute of Standards and Technology (NIST), one such technique using radiachromic films was considered, tested, and calibrated at the APS. This …
Date: February 28, 2000
Creator: Alderman, J.; Semones, E. & Job, P.K.
Object Type: Report
System: The UNT Digital Library
Achieve Continuous Injection of Solid Fuels into Advanced Combustion System Pressures (open access)

Achieve Continuous Injection of Solid Fuels into Advanced Combustion System Pressures

This report is a descriptive journey of the Achieve Continuous Injection of Solid Fuels into Advanced Combustion System Pressures.
Date: February 28, 2008
Creator: Aldred, Derek L. & Saunders, Timothy
Object Type: Report
System: The UNT Digital Library
Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 9, Ed. 1 Thursday, February 28, 2008 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 9, Ed. 1 Thursday, February 28, 2008

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: February 28, 2008
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Gravi-Leptogenesis: Leptogenesis From Gravity Waves in Pseudo-Scalar Driven Inflation Models (open access)

Gravi-Leptogenesis: Leptogenesis From Gravity Waves in Pseudo-Scalar Driven Inflation Models

In this talk we present a mechanism for leptogenesis which is based on gravity waves produced during inflation. We show that when inflation is driven by a pseudo-scalar field the metric perturbations generated during inflation can become birefringent, therefore giving a non-vanishing contribution to the gravitational triangle anomaly and sourcing lepton anti-lepton asymmetry. As this asymmetry is sourced by the fields which are active during inflation, it is not washed out or diluted by inflation. The amount of matter asymmetry generated in our model can be of realistic size for the parameters within the range of some inflationary scenarios and grand unified theories.
Date: February 28, 2007
Creator: Alexander, S. H.; Peskin, Michael E. & Sheikh-Jabbari, M. M.
Object Type: Article
System: The UNT Digital Library
Plasma and Ion Assistance in Physical Vapor Deposition: AHistorical Perspective (open access)

Plasma and Ion Assistance in Physical Vapor Deposition: AHistorical Perspective

Deposition of films using plasma or plasma-assist can betraced back surprisingly far, namely to the 18th century for arcs and tothe 19th century for sputtering. However, only since the 1960s thecoatings community considered other processes than evaporation for largescale commercial use. Ion Plating was perhaps the first importantprocess, introducing vapor ionization and substrate bias to generate abeam of ions arriving on the surface of the growing film. Ratherindependently, cathodic arc deposition was established as an energeticcondensation process, first in the former Soviet Union in the 1970s, andin the 1980s in the Western Hemisphere. About a dozen various ion-basedcoating technologies evolved in the last decades, all characterized byspecific plasma or ion generation processes. Gridded and gridless ionsources were taken from space propulsion and applied to thin filmdeposition. Modeling and simulation have helped to make plasma and ionseffects to be reasonably well understood. Yet--due to the complex, oftennon-linear and non-equilibrium nature of plasma and surfaceinteractions--there is still a place for the experience plasma"sourcerer."
Date: February 28, 2007
Creator: Anders, Andre
Object Type: Article
System: The UNT Digital Library
Plasma and Ion Sources in Large Area Coatings: A Review (open access)

Plasma and Ion Sources in Large Area Coatings: A Review

Efficient deposition of high-quality coatings often requires controlled application of excited or ionized particles. These particles are either condensing (film-forming) or assisting by providing energy and momentum to the film growth process, resulting in densification, sputtering/etching, modification of stress, roughness, texture, etc. In this review, the technical means are surveyed enabling large area application of ions and plasmas, with ion energies ranging from a few eV to a few keV. Both semiconductortype large area (single wafer or batch processing with {approx} 1000 cm{sup 2}) and in-line web and glass-coating-type large area (> 10{sup 7} m{sup 2} annually) are considered. Characteristics and differences between plasma and ion sources are explained. The latter include gridded and gridless sources. Many examples are given, including sources based on DC, RF, and microwave discharges, some with special geometries like hollow cathodes and E x B configurations.
Date: February 28, 2005
Creator: Anders, Andre
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 106, No. 278, Ed. 1 Monday, February 28, 2005 (open access)

Altus Times (Altus, Okla.), Vol. 106, No. 278, Ed. 1 Monday, February 28, 2005

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: February 28, 2005
Creator: Andrews, Mike
Object Type: Newspaper
System: The Gateway to Oklahoma History
The United Kingdom: Issues for the United States (open access)

The United Kingdom: Issues for the United States

This report assesses the current state of U.S.-UK relations. It examines the pressures confronting London as it attempts to balance its interests between the United States and the EU, and the prospects for the future of the U.S.-UK partnership, especially in the unfolding Brown era. It also describes UK views on political, security, and economic issues of particular importance to the United States, and their implications for U.S. policy that may be of interest in the second session of the 110th Congress.
Date: February 28, 2008
Creator: Archick, Kristin
Object Type: Report
System: The UNT Digital Library
Analysis of the structure of complex networks at different resolution levels (open access)

Analysis of the structure of complex networks at different resolution levels

Modular structure is ubiquitous in real-world complex networks, and its detection is important because it gives insights in the structure-functionality relationship. The standard approach is based on the optimization of a quality function, modularity, which is a relative quality measure for a partition of a network into modules. Recently some authors have pointed out that the optimization of modularity has a fundamental drawback: the existence of a resolution limit beyond which no modular structure can be detected even though these modules might have own entity. The reason is that several topological descriptions of the network coexist at different scales, which is, in general, a fingerprint of complex systems. Here we propose a method that allows for multiple resolution screening of the modular structure. The method has been validated using synthetic networks, discovering the predefined structures at all scales. Its application to two real social networks allows to find the exact splits reported in the literature, as well as the substructure beyond the actual split.
Date: February 28, 2008
Creator: Arenas, A.; Fernandez, A. & Gomez, S.
Object Type: Article
System: The UNT Digital Library
IMPACTS OF REDUCING CONDITIONS IN THE SATURATED ZONE AT YUCCA MOUNTAIN (open access)

IMPACTS OF REDUCING CONDITIONS IN THE SATURATED ZONE AT YUCCA MOUNTAIN

Variations in groundwater redox chemistry in the saturated zone near Yucca Mountain could have significant repository to the accessible environment. This study examines geochemical data relevant to the distribution of redox impacts on processes associated with the potential transport of redox-sensitive radionuclides from the proposed conditions in the saturated zone, the relationships between redox state and solubility and sorption coefficients for technetium and neptunium, and sensitivity in transport model simulations. Results indicate evidence for a zone of reducing conditions in the volcanic rocks of the saturated zone located to the east and south of the repository and along the inferred flow paths from the repository. A working hypothesis is that these reducing conditions are related to the presence of minor pyrite in the matrix of some volcanic units. Chemical equilibrium modeling of technetium solubility using EQ3/6 software codes is used to estimate the value of solubility limits as a function of Eh. Surface complexation modeling with the EQ3 code is used to estimate neptunium sorption coefficient values as a function of Eh. A general analytical approach, one-dimensional reactive transport modeling, and the three-dimensional saturated zone site-scale transport model using the FEHM software code are used to evaluate the impacts of …
Date: February 28, 2006
Creator: Arnold, B.W.; Meijer, A.; Kalinina, E.; Robinson, B.; Kelkar, S.; Jove-Colon, C. et al.
Object Type: Report
System: The UNT Digital Library
Atmospheric Radiation Measurement Program Facilities Newsletter, February 2003. (open access)

Atmospheric Radiation Measurement Program Facilities Newsletter, February 2003.

Monthly newsletter discussing news and activities related to the Atmospheric Radiation Measurement Program, articles about weather and atmospheric phenomena, and other related topics.
Date: February 28, 2003
Creator: Atmospheric Radiation Measurement Program (U.S.)
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Conference Reports and Joint Explanatory Statements (open access)

Conference Reports and Joint Explanatory Statements

The conference report presents the formal legislative language on which the conference committee has agreed. The joint explanatory statement explains the various elements of the conferees agreement in relation to the positions that the House and Senate had committed to the conference committee.
Date: February 28, 2003
Creator: Bach, Stanley & Davis, Christopher M.
Object Type: Report
System: The UNT Digital Library
Conference Reports and Joint Explanatory Statements (open access)

Conference Reports and Joint Explanatory Statements

The conference report presents the formal legislative language on which the conference committee has agreed. The joint explanatory statement explains the various elements of the conferees’ agreement in relation to the positions that the House and Senate had committed to the conference committee.
Date: February 28, 2003
Creator: Bach, Stanley & Davis, Christopher M.
Object Type: Report
System: The UNT Digital Library
House Rules Affecting Committees (open access)

House Rules Affecting Committees

This report identifies and summarizes the provisions of the House's standing rules and certain other directives that affect committee powers, authority, activities, and operations.
Date: February 28, 2003
Creator: Bach, Stanley & Davis, Christopher M.
Object Type: Report
System: The UNT Digital Library
Senate Rules Affecting Committees (open access)

Senate Rules Affecting Committees

This report identifies and summarizes the provisions of the Senate's standing rules, standing orders, precedents, and other directives that relate to legislative activity in the Senate's standing committees. It covers four main issues: committee organization, committee meetings, hearings, and reporting.
Date: February 28, 2003
Creator: Bach, Stanley & Palmer, Betsy
Object Type: Report
System: The UNT Digital Library
Data Evaluation for 56Co epsilon + beta+ Decay (open access)

Data Evaluation for 56Co epsilon + beta+ Decay

Recommended values for nuclear and atomic data pertaining to the {var_epsilon} + {beta}{sup +} decay of {sup 56}Co are provided here, followed by comments on evaluation procedures and a summary of all available experimental data. {sup 56}Co is a radionuclide which is potentially very useful for Ge detector efficiency calibration because it is readily produced via the {sup 56}Fe(p,n) reaction, its half-life of 77.24 days is conveniently long, and it provides a number of relatively strong {gamma} rays with energies up to {approx}3500 keV. The transition intensities recommended here for the strongest lines will be included in the forthcoming International Atomic Energy Agency Coordinated Research Programme document ''Update of X- and Gamma-ray Decay Data Standards for Detector Calibration and Other Applications'', and the analysis for all transitions along with relevant atomic data have been provided to the Decay Data Evaluation Project.
Date: February 28, 2005
Creator: Baglin, Coral M. & MacMahon, T. Desmond
Object Type: Report
System: The UNT Digital Library
Solution to Problem 11275 (open access)

Solution to Problem 11275

None
Date: February 28, 2007
Creator: Bailey, David H. & Borwein, Jonathan M.
Object Type: Report
System: The UNT Digital Library