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Gordon Conference - Cluster, Nanocrystals and Nanostructures - July 29th - August 3rd, 2007 (open access)

Gordon Conference - Cluster, Nanocrystals and Nanostructures - July 29th - August 3rd, 2007

None
Date: June 14, 2007
Creator: A. Welford Castleman, Jr.
Object Type: Report
System: The UNT Digital Library
Hydrogen Permeability of Mulitphase V-Ti-Ni Metallic Membranes (open access)

Hydrogen Permeability of Mulitphase V-Ti-Ni Metallic Membranes

None
Date: February 14, 2006
Creator: ADAMS, THAD
Object Type: Article
System: The UNT Digital Library
EXAMPLE OF A RISK BASED DISPOSAL APPROVAL SOLIDIFICATION OF HANFORD SITE TRANSURANIC (TRU) WASTE (open access)

EXAMPLE OF A RISK BASED DISPOSAL APPROVAL SOLIDIFICATION OF HANFORD SITE TRANSURANIC (TRU) WASTE

The Hanford Site requested, and the U.S. Environmental Protection Agency (EPA) Region 10 approved, a Toxic Substances Control Act of 1976 (TSCA) risk-based disposal approval (RBDA) for solidifying approximately four cubic meters of waste from a specific area of one of the K East Basin: the North Loadout Pit (NLOP). The NLOP waste is a highly radioactive sludge that contained polychlorinated biphenyls (PCBs) regulated under TSCA. The prescribed disposal method for liquid PCB waste under TSCA regulations is either thermal treatment or decontamination. Due to the radioactive nature of the waste, however, neither thermal treatment nor decontamination was a viable option. As a result, the proposed treatment consisted of solidifying the material to comply with waste acceptance criteria at the Waste Isolation Pilot Plant (WPP) in Carlsbad, New Mexico, or possibly the Environmental Restoration Disposal Facility at the Hanford Site, depending on the resulting transuranic (TRU) content of the stabilized waste. The RBDA evaluated environmental risks associated with potential airborne PCBs. In addition, the RBDA made use of waste management controls already in place at the treatment unit. The treatment unit, the T Plant Complex, is a Resource Conservation and Recovery Act of 1976 (RCRA)-permitted facility used for storing and …
Date: November 14, 2007
Creator: AL, PRIGNANO
Object Type: Article
System: The UNT Digital Library
A Measurement of the Spatial Distribution of Diffuse TeV Gamma Ray Emission from the Galactic Plane with Milagro (open access)

A Measurement of the Spatial Distribution of Diffuse TeV Gamma Ray Emission from the Galactic Plane with Milagro

Diffuse {gamma}-ray emission produced by the interaction of cosmic-ray particles with matter and radiation in the Galaxy can be used to probe the distribution of cosmic rays and their sources in different regions of the Galaxy. With its large field of view and long observation time, the Milagro Gamma Ray Observatory is an ideal instrument for surveying large regions of the Northern Hemisphere sky and for detecting diffuse {gamma}-ray emission at very high energies. Here, the spatial distribution and the flux of the diffuse {gamma}-ray emission in the TeV energy range with a median energy of 15 TeV for Galactic longitudes between 30{sup o} and 110{sup o} and between 136{sup o} and 216{sup o} and for Galactic latitudes between -10{sup o} and 10{sup o} are determined. The measured fluxes are consistent with predictions of the GALPROP model everywhere except for the Cygnus region (l {element_of} [65{sup o}, 85{sup o}]). For the Cygnus region, the flux is twice the predicted value. This excess can be explained by the presence of active cosmic ray sources accelerating hadrons which interact with the local dense interstellar medium and produce gamma rays through pion decay.
Date: May 14, 2008
Creator: Abdo, A. A.; Allen, B.; Aune, T.; Berley, D.; Blaufuss, E.; Casanova, S. et al.
Object Type: Article
System: The UNT Digital Library
Electricity: The Road Toward Restructuring (open access)

Electricity: The Road Toward Restructuring

The Public Utility Holding Company Act of 1935 (PUHCA) and the Federal Power Act (FPA) were enacted to eliminate unfair practices and other abuses by electricity and gas holding companies by requiring federal control and regulation of interstate public utility holding companies. Comprehensive energy legislation has passed the House and Senate. The House passed H.R. 6 on April 11, 2003. On July 31, 2003, the Senate suspended debate on S. 14, inserted the text of H.R. 4 (107th Congress) as a substitute, and passed H.R. 6. A conference agreement was reached November 17, 2003, and passed by the House the next day. H.R. 6 includes an electricity title that would, in part, repeal PUHCA, would prospectively repeal the mandatory purchase requirement under PURPA, and would create an electric reliability organization. On June 15, 2004, H.R. 4503, a comprehensive energy policy bill, passed the House.
Date: March 14, 2003
Creator: Abel, Amy & Parker, Larry
Object Type: Report
System: The UNT Digital Library
HCCI Combustion: Analysis and Experiments (open access)

HCCI Combustion: Analysis and Experiments

Homogeneous charge compression ignition (HCCI) is a new combustion technology that may develop as an alternative to diesel engines with high efficiency and low NOx and particulate matter emissions. This paper describes the HCCI research activities being currently pursued at Lawrence Livermore National Laboratory and at the University of California Berkeley. Current activities include analysis as well as experimental work. On analysis, we have developed two powerful tools: a single zone model and a multi-zone model. The single zone model has proven very successful in predicting start of combustion and providing reasonable estimates for peak cylinder pressure, indicated efficiency and NOX emissions. This model is being applied to develop detailed engine performance maps and control strategies, and to analyze the problem of engine startability. The multi-zone model is capable of very accurate predictions of the combustion process, including HC and CO emissions. The multi-zone model h as applicability to the optimization of combustion chamber geometry and operating conditions to achieve controlled combustion at high efficiency and low emissions. On experimental work, we have done a thorough evaluation of operating conditions in a 4-cylinder Volkswagen TDI engine. The engine has been operated over a wide range of conditions by adjusting the …
Date: May 14, 2001
Creator: Aceves, Salvador M.; Flowers, Daniel L.; Martinez-Frias, Joel; Smith, J. Ray; Dibble, Robert; Au, Michael et al.
Object Type: Article
System: The UNT Digital Library
Declarations of War and Authorizations for the Use of Military Force: Historical Background and Legal Implications (open access)

Declarations of War and Authorizations for the Use of Military Force: Historical Background and Legal Implications

This report provides historical background on the enactment of declarations of war and authorizations for the use of force and analyzes their legal effects under international and domestic law. It also sets forth their texts in two appendices. Because the statutes that confer standby authority on the President and the executive branch potentially play such a large role in an armed conflict to which the United States is a party, the report includes an extensive listing and summary of the statutes that are triggered by a declaration of war, a declaration of national emergency, and/or the existence of a state of war. The report concludes with a summary of the Congressional procedures applicable to the enactment of a declaration of war or authorization for the use of force and to measures under the War Powers Resolution.
Date: January 14, 2003
Creator: Ackerman, David M. & Grimmett, Richard F.
Object Type: Report
System: The UNT Digital Library
Assessing Terrorist Motivations for Attacking Critical "Chemical" Infrastructure (open access)

Assessing Terrorist Motivations for Attacking Critical "Chemical" Infrastructure

Certain types of infrastructure--critical infrastructure (CI)--play vital roles in underpinning our economy, security, and way of life. One particular type of CI--that relating to chemicals--constitutes both an important element of our nation's infrastructure and a particularly attractive set of potential targets. This is primarily because of the large quantities of toxic industrial chemicals (TICs) it employs in various operations and because of the essential economic functions it serves. This study attempts to minimize some of the ambiguities that presently impede chemical infrastructure threat assessments by providing new insight into the key motivational factors that affect terrorist organizations propensity to attack chemical facilities. Prepared as a companion piece to the Center for Nonproliferation Studies August 2004 study--''Assessing Terrorist Motivations for Attacking Critical Infrastructure''--it investigates three overarching research questions: (1) why do terrorists choose to attack chemical-related infrastructure over other targets; (2) what specific factors influence their target selection decisions concerning chemical facilities; and (3) which, if any, types of groups are most inclined to attack chemical infrastructure targets? The study involved a multi-pronged research design, which made use of four discrete investigative techniques to answer the above questions as comprehensively as possible. These include: (1) a review of terrorism and threat …
Date: December 14, 2004
Creator: Ackerman, G.; Bale, J. & Moran, K.
Object Type: Report
System: The UNT Digital Library
Top physics: measurement of the tt-bar production cross section in pp-bar collisions at s**(1/2) = 1.96 tev using dilepton event (open access)

Top physics: measurement of the tt-bar production cross section in pp-bar collisions at s**(1/2) = 1.96 tev using dilepton event

We report a measurement of the t{bar t} production cross section using dilepton events with jets and missing transverse energy in p{bar p} collisions at a center-of-mass energy of 1.96 TeV. Using a 197 {+-} 12 pb{sup -1} data sample recorded by the upgraded Collider Detector at Fermilab, we use two complementary techniques to select candidate events. We compare the number of observed events and selected kinematical distributions with the predictions of the standard model and find good agreement. The combined result of the two techniques yields a t{bar t} production cross section of 7.0{sub -2.1}{sup +2.4}(stat){sub -1.1}{sup _1.6}(syst) {+-} 0.4(lum) pb.
Date: October 14, 2004
Creator: Acosta, D.
Object Type: Report
System: The UNT Digital Library
Top physics: search for anomalous kinematics in t anti-t dilepton events at cdf ii (open access)

Top physics: search for anomalous kinematics in t anti-t dilepton events at cdf ii

We report on a search for anomalous kinematics of t{bar t} dilepton events in p{bar p} collisions at {radical}s = 1.96 TeV using 193 pb{sup -1} of data collected with the CDF II detector. We developed a new a priori technique designed to isolate the subset in a data sample revealing the largest deviation from standard model (SM) expectations and to quantify the significance of this departure. In the four-variable space considered, no particular subset shows a significant discrepancy and we find that the probability of obtaining a data sample less consistent with the SM than what is observed is 1.0-4.5%.
Date: December 14, 2004
Creator: Acosta, D.
Object Type: Report
System: The UNT Digital Library
Tank Characterization Report for Double Shell Tank 241AZ102 (open access)

Tank Characterization Report for Double Shell Tank 241AZ102

None
Date: September 14, 2000
Creator: Adams, M. R.
Object Type: Report
System: The UNT Digital Library
Orientation for New State WAP Directors and Staff (open access)

Orientation for New State WAP Directors and Staff

NASCSP has been providing The Orientation for New Weatherization Assistance Program (WAP) State Directors and Staff yearly for the past four years. This report is a general description of the trainings and supporting documentation from the most recent event. The Orientation and Training provides attendees with a comprehensive overview of the WAP from the federal, state, and local perspectives. A variety of presenters make information available on a wide range of subjects deemed necessary to effectively operate the Program. During the first day of training, staff from the Department of Energy WAP office, NASCSP, the National Energy Assistance Director's Association, Economic Opportunity Studies, and Oak Ridge National Laboratory present materials and participate in open discussion with the attendees about the federal program requirements. Some of the day's subjects include: History of the WAP; Funding, Rules, Regulations, and Program Guidance Documents; WAP State Plan Application Process and Submission; Training and Technical Assistance Activity; Administration and Federal/State Monitoring Requirements; and National Significance of WAP and the Political Process. The second day focuses on implementation strategies for the Program. Presenters from state offices and local management provide their perspective on the following subjects: Utility Restructuring Integration Strategies; Program Expansion Issues; Integration of New …
Date: April 14, 2003
Creator: Adams, Robert & Barone, Tracy
Object Type: Report
System: The UNT Digital Library
Meteorological Support at the Savanna River Site (open access)

Meteorological Support at the Savanna River Site

The Department of Energy (DOE) operates many nuclear facilities on large complexes across the United States in support of national defense. The operation of these many and varied facilities and processes require meteorological support for many purposes, including: for routine operations, to respond to severe weather events, such as lightning, tornadoes and hurricanes, to support the emergency response functions in the event of a release of materials to the environment, for engineering baseline and safety documentation, as well as hazards assessments etc. This paper describes a program of meteorological support to the Savannah River Site, a DOE complex located in South Carolina.
Date: October 14, 2005
Creator: Addis, Robert P.
Object Type: Article
System: The UNT Digital Library
Modeling the Cathodic Region in Crevice Corrosion Under a Thin Electrolyte Film Including Particulates (open access)

Modeling the Cathodic Region in Crevice Corrosion Under a Thin Electrolyte Film Including Particulates

Crevice corrosion may be limited by the capacity of the external cathodic region to support anodic dissolution currents within the crevice. The analysis here focuses on behavior of metal surfaces covered by a thin ({approx}microns) layer of the electrolyte film including particulates. The particulates can affect the cathode current capacity (I{sub total}) by increasing the solution resistance (''volume effect'') and by decreasing the electrode area (''surface effect''). In addition, there can be particulate effects on oxygen reduction kinetics and oxygen transport. This work simulates and characterizes the effect of a uniform particulate monolayer on the cathode current capacity for steady state conditions in the presence of a thin electrolyte film. Particulate configurations with varying particle size, shape, arrangement, volume fraction, and electrode area coverage were numerically modeled as a function of the properties of the system. It is observed that the effects of particles can be fully accounted for in terms of two corrections: the volume blockage effect on the electrolyte resistivity can be correlated using Bruggeman's equation, and the electrode coverage effect can be modeled in terms of a simple area correction to the kinetics expression. For the range of parameters analyzed, applying these two correction factors, cathodes covered …
Date: March 14, 2006
Creator: Agarwal, A. S.; Landau, U.; Shan, X. & Payer, J. H.
Object Type: Report
System: The UNT Digital Library
Supporting Dynamic Ad hoc Collaboration Capabilities (open access)

Supporting Dynamic Ad hoc Collaboration Capabilities

Modern HENP experiments such as CMS and Atlas involve as many as 2000 collaborators around the world. Collaborations this large will be unable to meet often enough to support working closely together. Many of the tools currently available for collaboration focus on heavy-weight applications such as videoconferencing tools. While these are important, there is a more basic need for tools that support connecting physicists to work together on an ad hoc or continuous basis. Tools that support the day-to-day connectivity and underlying needs of a group of collaborators are important for providing light-weight, non-intrusive, and flexible ways to work collaboratively. Some example tools include messaging, file-sharing, and shared plot viewers. An important component of the environment is a scalable underlying communication framework. In this paper we will describe our current progress on building a dynamic and ad hoc collaboration environment and our vision for its evolution into a HENP collaboration environment.
Date: July 14, 2003
Creator: Agarwal, Deborah A. & Berket, Karlo
Object Type: Article
System: The UNT Digital Library
The Eastern Statesman (Wilburton, Okla.), Vol. 81, No. 10, Ed. 1 Friday, February 14, 2003 (open access)

The Eastern Statesman (Wilburton, Okla.), Vol. 81, No. 10, Ed. 1 Friday, February 14, 2003

Biweekly student newspaper from Eastern Oklahoma State College in Wilburton, Oklahoma that includes local, state, and campus news along with advertising.
Date: February 14, 2003
Creator: Agent, Alicia
Object Type: Newspaper
System: The Gateway to Oklahoma History
On the Increasing Fragility of Human Teeth with Age: ADeep-Ultraviolet Resonance Raman Study (open access)

On the Increasing Fragility of Human Teeth with Age: ADeep-Ultraviolet Resonance Raman Study

Ultraviolet resonance Raman spectroscopy (UVRRS) using 244nm excitation was used to investigate the impact of aging on humandentin. The intensity of a spectroscopic feature from the peptide bondsin the collagen increases with tissue age, similar to a finding reportedpreviously for human cortical bone.
Date: July 14, 2006
Creator: Ager, J. W., III; Nalla, R. K.; Balooch, G.; Kim, G.; Pugach, M.; Habelitz, S. et al.
Object Type: Article
System: The UNT Digital Library
The Black Hole in the Throat - Thermodynamics of Strongly Coupled Cascading Gauge Theories (open access)

The Black Hole in the Throat - Thermodynamics of Strongly Coupled Cascading Gauge Theories

We numerically construct black hole solutions corresponding to the deconfined, chirally symmetric phase of strongly coupled cascading gauge theories at various temperatures. We compute the free energy as a function of the temperature, and we show that it becomes positive below some critical temperature, indicating the possibility of a first order phase transition at which the theory deconfines and restores the chiral symmetry.
Date: June 14, 2007
Creator: Aharony, Ofer; /Weizmann Inst. /Stanford U., ITP /SLAC; Buchel, Alex; Phys., /Western Ontario U. /Perimeter Inst. Theor.; Kerner, Patrick & U., /Western Ontario
Object Type: Report
System: The UNT Digital Library
European Union–U.S. Trade and Investment Relations: Key Issues (open access)

European Union–U.S. Trade and Investment Relations: Key Issues

None
Date: February 14, 2008
Creator: Aheam, Raymond J.; Fischer, John W.; Goldfarb, Charles B.; Hanrahan, Charles E.; Eubanks, Walter W. & Rubin, Janice E.
Object Type: Report
System: The UNT Digital Library
U.S.-European Union Relations and the 2007 Summit (open access)

U.S.-European Union Relations and the 2007 Summit

This report evaluates the results of the annual U.S.-EU summit on April 30, 2007, in Washington, DC.
Date: May 14, 2007
Creator: Ahearn, Raymond; Archick, Kristin & Belkin, Paul
Object Type: Report
System: The UNT Digital Library
Measured energy savings from the application of reflective roofsin 2 small non-residential buildings (open access)

Measured energy savings from the application of reflective roofsin 2 small non-residential buildings

Energy use and environmental parameters were monitored in two small (14.9 m{sup 2}) non-residential buildings during the summer of 2000. The buildings were initially monitored for about 1 1/2 months to establish a base condition. The roofs of the buildings were then painted with a white coating and the monitoring was continued. The original solar reflectivities of the roofs were about 26%; after the application of roof coatings the reflectivities increased to about 72%. The monitored electricity savings were about 0.5kWh per day (33 Wh/m2 per day). The estimated annual savings are about 125kWh per year (8.4 kWh/m2); at a cost of $0.1/kWh, savings are about $0.86/m2 per year. Obviously, it costs significantly more than this amount to coat the roofs with reflective coating, particularly because of the remote locations of these buildings. However, since the prefabricated roofs are already painted green at the factory, painting them a white (reflective) color would bring no additional cost. Hence, a reflective roof saves energy at no incremental cost.
Date: January 14, 2003
Creator: Akbari, Hashem
Object Type: Article
System: The UNT Digital Library
Urban Surfaces and Heat Island Mitigation Potentials (open access)

Urban Surfaces and Heat Island Mitigation Potentials

Data on materials and surface types that comprise a city, i.e. urban fabric, are needed in order to estimate the effects of light-colored surfaces (roofs and pavements) and urban vegetation (trees, grass, shrubs) on the meteorology and air quality of a city. We discuss the results of a semi-automatic statistical approach used to develop data on surface-type distribution and urban-fabric makeup using aerial color orthophotography, for four metropolitan areas of Chicago, IL, Houston, TX, Sacramento, CA, and Salt Lake City, UT. The digital high resolution (0.3 to 0.5-m) aerial photographs for each of these metropolitan areas covers representative urban areas ranging from 30 km{sup 2} to 52 km{sup 2}. Major land-use types examined included: commercial, residential, industrial, educational, and transportation. On average, for the metropolitan areas studied, vegetation covers about 29-41% of the area, roofs 19-25%, and paved surfaces 29-39%. For the most part, trees shade streets, parking lots, grass, and sidewalks. At ground level, i.e., view from below the tree canopies, vegetation covers about 20-37% of the area, roofs 20-25%, and paved surfaces 29-36%.
Date: June 14, 2007
Creator: Akbari, Hashem; Akbari, Hashem & Shea Rose, Leanna
Object Type: Article
System: The UNT Digital Library
Global Cooling: Increasing World-Wide Urban Albedos to Offset CO2 (open access)

Global Cooling: Increasing World-Wide Urban Albedos to Offset CO2

Modification of urban albedos reduces summertime urban temperatures, resulting in a better urban air quality and building air-conditioning savings. Furthermore, increasing urban albedos has the added benefit of reflecting some of the incoming global solar radiation and countering to some extent the effects of global warming. In many urban areas, pavements and roofs constitute over 60% of urban surfaces (roof 20-25%, pavements about 40%). Using reflective materials, both roof and the pavement albedos can be increased by about 0.25 and 0.10, respectively, resulting in a net albedo increase for urban areas of about 0.1. Many studies have demonstrated building cooling-energy savings in excess of 20% upon raising roof reflectivity from an existing 10-20% to about 60% (a U.S. potential savings in excess of $1 billion (B) per year in net annual energy bills). On a global basis, our preliminary estimate is that increasing the world-wide albedos of urban roofs and paved surfaces will induce a negative radiative forcing on the earth equivalent to removing {approx} 22-40 Gt of CO{sub 2} from the atmosphere. Since, 55% of the emitted CO{sub 2} remains in the atmosphere, removal of 22-40 Gt of CO{sub 2} from the atmosphere is equivalent to reducing global CO{sub …
Date: January 14, 2008
Creator: Akbari, Hashem; Menon, Surabi & Rosenfeld, Arthur
Object Type: Article
System: The UNT Digital Library
Development of a Novel Catalyst for NO Decomposition (open access)

Development of a Novel Catalyst for NO Decomposition

Air pollution arising from the emission of nitrogen oxides as a result of combustion taking place in boilers, furnaces and engines, has increasingly been recognized as a problem. New methods to remove NOx emissions significantly and economically must be developed. The current technology for post-combustion removal of NO is the selective catalytic reduction (SCR) of NO by ammonia or possibly by a hydrocarbon such as methane. The catalytic decomposition of NO to give N2 will be preferable to the SCR process because it will eliminate the costs and operating problems associated with the use of an external reducing species. The most promising decomposition catalysts are transition metal (especially copper)-exchanged zeolites, perovskites, and noble metals supported on metal oxides such as alumina, silica, and ceria. The main shortcoming of the noble metal reducible oxide (NMRO) catalysts is that they are prone to deactivation by oxygen. It has been reported that catalysts containing tin oxide show oxygen adsorption behavior that may involve hydroxyl groups attached to the tin oxide. This is different than that observed with other noble metal-metal oxide combinations, which have the oxygen adsorbing on the noble metal and subsequently spilling over to the metal oxide. This observation leads one …
Date: March 14, 2007
Creator: Akyurtlu, Ates & Akyurtlu, Jale F.
Object Type: Report
System: The UNT Digital Library