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Production of [15O] Water at Low-Energy Proton Cyclotrons

Description: We report a simple system for producing [15O]H2O from nitrogen-15 in a nitrogen/hydrogen gas target with recycling of the target nitrogen, allowing production on low-energy proton-only accelerators with minimal consumption of isotopically enriched nitrogen-15. The radiolabeled water is separated from the target gas and radiolytically produced ammonia by temporary freezing in a small trap at -40 C.
Date: December 12, 2005
Creator: Powell, James & O'Neil, James P.
Partner: UNT Libraries Government Documents Department

Production of an Accelerated Oxygen-14 Beam

Description: BEARS is an ongoing project to provide a light-ion radioactive-beam capability at the 88-Inch Cyclotron at LBNL. Light radioactive isotopes are produced at a 10 MeV proton medical cyclotron, transported 350 m via a high-speed gas transport capillary, cryogenically separated, and injected into the 88-Inch Cyclotron's ion source. The first radioactive beam successfully accelerated was Carbon-11 and beams of intensity more than 108 ions/sec have been utilized for experiments. Development of Oxygen-14 as the second BEARS beam presented considerable technical challenges, both due to its short half-life of 71 seconds and the radiation chemistry of oxygen in the target. The usual techniques developed for medical uses of Oxygen-15 involve the addition of significant amounts of carrier oxygen, something that would overload the ion source. As a solution, Oxygen-14 is produced as water in a carrier-free form, and is chemically converted in two steps to carbon dioxide, a form readily usable by the BEARS. This system has been built and is operational, and initial tests of accelerating an Oxygen-14 beam have been performed.
Date: May 3, 2002
Creator: Powell, James; O'Neil, James P. & Cerny, Joseph
Partner: UNT Libraries Government Documents Department

Reducing Our Carbon Footprint through Ridesharing

Description: This report discusses research on reducing our carbon footprint through ridesharing. The focus of this research project was to analyze and collect travel trajectories to calculate carbon footprints under different travel modes and identify ways to reduce it.
Date: 2012
Creator: Garrett, Kim; Bell, Jesse; Huang, Yan & Powell, James
Partner: UNT College of Engineering

The fierce urgency of now: a proactive, pervasive content awareness tool

Description: Information awareness is distinct from explicit infonnation seeking, such as searching. We describe an information awareness tool that supports text composition by providing awareness of relevant content and references proactively and non-intrusively. As a user composes text, the tool automatically searches mUltiple sources, retrieves results, and displays links to the results. The tool has been implemented using Web 2.0 and Digital Library 2.0 technologies, and is flexible and highly configurable.
Date: January 1, 2009
Creator: Powell, James E; Collins, Linn M & Martinez, Mark L B
Partner: UNT Libraries Government Documents Department

Using architectures for semantic interoperability to create journal clubs for emergency response

Description: In certain types of 'slow burn' emergencies, careful accumulation and evaluation of information can offer a crucial advantage. The SARS outbreak in the first decade of the 21st century was such an event, and ad hoc journal clubs played a critical role in assisting scientific and technical responders in identifying and developing various strategies for halting what could have become a dangerous pandemic. This research-in-progress paper describes a process for leveraging emerging semantic web and digital library architectures and standards to (1) create a focused collection of bibliographic metadata, (2) extract semantic information, (3) convert it to the Resource Description Framework /Extensible Markup Language (RDF/XML), and (4) integrate it so that scientific and technical responders can share and explore critical information in the collections.
Date: January 1, 2009
Creator: Powell, James E; Collins, Linn M & Martinez, Mark L B
Partner: UNT Libraries Government Documents Department

Study of the 11C(p,gamma) reaction via the indirect d(11C,12N)ntransfer reaction

Description: The {sup 11}C(p,{gamma}){sup 12}N reaction is expected to be an important branch point in supermassive low-metallicity stars because it could produce CNO seed nuclei before the traditional triple-alpha process turns on. In the present work, the d({sup 11}C, {sup 12}N)n transfer reaction was employed to evaluate this reaction using a radioactive ion beam of 150 MeV {sup 11}C with 6 x 10{sup 5} ions/s on target from the BEARS project at the 88-inch cyclotron at Lawrence Berkeley National Laboratory. Excellent agreement was obtained between the experimental cross sections ({theta}{sub c.m.} = 10.9{sup o} to 71.5{sup o}) and DWBA calculations. The asymptotic normalization coefficient was deduced to be (C{sub eff}{sup 12N}){sup 2} = (C{sub p1/2}{sup 12N}){sup 2} + (C{sub p3/2}{sup 12N}){sup 2} = 1.83 {+-} 0.27 fm{sup -1}.
Date: January 7, 2008
Creator: Lee, Dongwon; Powell, James; Perajarvi, Kari; Guo, Fanqing; Moltz, Dennis & Cerny, Joseph
Partner: UNT Libraries Government Documents Department

Protocols for Authorized Release of Concrete

Description: Much of the clean or slightly contaminated concrete from Decontamination and Decommissioning (D&D) activities could be re-used. Currently, there is no standardized approach, or protocol, for managing the disposition of such materials. Namely, all potential disposition options for concrete, including authorized release for re-use, are generally not fully evaluated in D&D projects, so large quantities have been unduly disposed of as low-level radioactive waste. As a result, costs of D&D have become prohibitively high, hindering expedient cleanup of surplus facilities. The ability to evaluate and implement the option of authorized release of concrete from demolition would result in significant cost savings, while maintaining protection of environmental health and safety, across the Department of Energy (DOE) complex. The Idaho National Engineering and Environmental Laboratory (INEEL), Argonne National Laboratory East (ANL-E), and Vanderbilt University have teamed to develop a protocol for the authorized release of concrete, based on the existing DOE guidance of Order 5400.5, that applies across the DOE complex. The protocol will provide a streamlined method for assessing risks and costs, and reaching optimal disposal options, including re-use of the concrete within the DOE system.
Date: June 1, 2000
Creator: Smith, Agatha Marie; Meservey, Richard Harlan; Chen, S.Y.; Powell, James Edward & PArker, F.
Partner: UNT Libraries Government Documents Department

Personalizing situation awareness

Description: Emergency responders need access to information but what counts as actionable information depends on their role, task, location, and other variables. For example, experts who have unique knowledge and experience and are called on to serve as scientific and teclmical responders, require correspondingly unique situation awareness in order to do their work. In our research-in-progress we leverage emerging and evolving web and digital library technologies to create personalized situation awareness tools that address the needs of these scientific and technical responders in real time, through focused information collection, extraction, integration, representation, and dissemination. We describe three personalized situation awareness tools in this paper: the Theme Awareness Tool (THEMAT), Social Awareness Tool (SAT), and Expertise Awareness Tool (EXPAT). The concepts and technologies we are developing in collaboration with experts apply to those who use the Web, in general, and offer an approach to the general issue of HCI design for emergencies.
Date: January 1, 2009
Creator: Collins, Linn Marks; Powell, James E; Roman, Jorge R; Martinez, Mark L B & Mane, Ketan K
Partner: UNT Libraries Government Documents Department

Design and Implementation of a Facility for Discovering New Scintillator Materials

Description: We describe the design and operation of a high-throughput facility for synthesizing thousands of inorganic crystalline samples per year and evaluating them as potential scintillation detector materials. This facility includes a robotic dispenser, arrays of automated furnaces, a dual-beam X-ray generator for diffractometery and luminescence spectroscopy, a pulsed X-ray generator for time response measurements, computer-controlled sample changers, an optical spectrometer, and a network-accessible database management system that captures all synthesis and measurement data.
Date: April 25, 2008
Creator: Derenzo, Stephen; Derenzo, Stephen E; Boswell, Martin S.; Bourret-Courchesne, Edith; Boutchko, Rostyslav; Budinger, Thomas F. et al.
Partner: UNT Libraries Government Documents Department