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Carbon Dioxide Information Analysis Center and World Data Center for Atmospheric Trace Gases Fiscal Year 2001 Annual Report

Description: The Carbon Dioxide Information Analysis Center (CDIAC), which includes the World Data Center (WDC) for Atmospheric Trace Gases, is the primary global change data and information analysis center of the U.S. Department of Energy (DOE). More than just an archive of data sets and publications, CDIAC has, since its inception in 1982, enhanced the value of its holdings through intensive quality assurance, documentation, and integration. Whereas many traditional data centers are discipline-based (for example, meteorology or oceanography), CDIAC's scope includes potentially anything and everything that would be of value to users concerned with the greenhouse effect and global climate change, including concentrations of carbon dioxide (CO{sub 2}) and other radiatively active gases in the atmosphere; the role of the terrestrial biosphere and the oceans in the biogeochemical cycles of greenhouse gases; emissions of CO{sub 2} and other trace gases to the atmosphere; long-term climate trends; the effects of elevated CO{sub 2} on vegetation; and the vulnerability of coastal areas to rising sea levels. CDIAC is located within the Environmental Sciences Division (ESD) at Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. CDIAC is co-located with ESD researchers investigating global-change topics, such as the global carbon cycle and the effects of carbon dioxide on climate and vegetation. CDIAC staff are also connected with current ORNL research on related topics, such as renewable energy and supercomputing technologies. CDIAC is supported by the Environmental Sciences Division (Jerry Elwood, Director) of DOE's Office of Biological and Environmental Research. CDIAC represents DOE in the multi-agency Global Change Data and Information System (GCDIS). Wanda Ferrell is DOE's Program Manager with overall responsibility for CDIAC. Roger Dahlman is responsible for CDIAC's AmeriFlux tasks, and Anna Palmisano for CDIAC's Ocean Data tasks. CDIAC is made up of three groups: Data Systems, Information Services, and Computer Systems, with ...
Date: October 15, 2002
Creator: Cushman, R.M.
Partner: UNT Libraries Government Documents Department

Towards measuring the charge radius of {sup 6}He and {sup 8}He.

Description: We report on the progress towards measuring the charge radius of {sup 6}He and {sup 8}He nuclei by performing laser spectroscopy on these helium atoms in a magneto optical trap (MOT). First tests to produce neutral {sup 6}He atoms via the {sup 12}C({sup 7}Li, {sup 6}He){sup 13}N reaction at the ATLAS accelerator have been successfully conducted. The MOT apparatus including the laser system and the discharge source to populate the metastable level are currently being set up.
Date: May 15, 2002
Creator: Mueller, P.; Wang, L.-B.; Bailey, K.; Drake, G. W. F.; Du, X.; Greens, J. et al.
Partner: UNT Libraries Government Documents Department

Electrical and optical properties of carbon-doped GaN grown by MBE on MOCVD GaN templates using a CCl4 dopant source

Description: Carbon-doped GaN was grown by plasma-assisted molecular-beam epitaxy using carbon tetrachloride vapor as the dopant source. For moderate doping mainly acceptors were formed, yielding semi-insulating GaN. However at higher concentrations p-type conductivity was not observed, and heavily doped films (>5 x 10{sup 20} cm{sup -3}) were actually n-type rather than semi-insulating. Photoluminescence measurements showed two broad luminescence bands centered at 2.2 and 2.9 eV. The intensity of both bands increased with carbon content, but the 2.2 eV band dominated in n-type samples. Intense, narrow ({approx}6 meV) donor-bound exciton peaks were observed in the semi-insulating samples.
Date: April 15, 2002
Creator: Armitage, Rob; Yang, Qing; Feick, Henning; Park, Yeonjoon & Weber, Eicke R.
Partner: UNT Libraries Government Documents Department

NERI Project 99-119. A New Paradigm for Automatic Development of Highly Reliable Control Architectures for Nuclear Power Plants. Phase-2 Progress Report

Description: This report describes the tasks performed and the progress made during Phase 2 of the DOE-NERI project number 99-119 entitled Automatic Development of Highly Reliable Control Architecture for Future Nuclear Power Plants. This project is a collaboration effort between the Oak Ridge National Laboratory (ORNL), The University of Tennessee, Knoxville (UTK) and the North Carolina State University (NCSU). ORNL is the lead organization and is responsible for the coordination and integration of all work.
Date: January 15, 2002
Creator: March-Leuba, JA
Partner: UNT Libraries Government Documents Department

Screw dislocations in GaN

Description: GaN has received much attention over the past few years because of several new applications, including light emitting diodes, blue laser diodes and high-power microwave transistors. One of the biggest problems is a high density of structural defects, mostly dislocations, due to a lack of a suitable lattice-matched substrate since bulk GaN is difficult to grow in large sizes. Transmission Electron Microscopy (TEM) has been applied to study defects in plan-view and cross-sections on samples prepared by conventional techniques such as mechanical thinning and precision ion milling. The density of dislocations close to the sample surface of a 1 mm-thick HVPE sample was in the range of 3x109 cm-2. All three types of dislocations were present in these samples, and almost 50 percent were screw dislocations. Our studies suggest that the core structure of screw dislocations in the same material might differ when the material is grown by different methods.
Date: February 15, 2002
Creator: Liliental-Weber, Zuzanna; Jasinski, Jacek B.; Washburn, Jack & O'Keefe, Michael A.
Partner: UNT Libraries Government Documents Department

Steady-State Simulation of Steam Reforming of INEEL Tank Farm Waste

Description: A steady-state model of the Sodium-Bearing Waste steam reforming process at the Idaho National Engineering and Environmental Laboratory has been performed using the commercial ASPEN Plus process simulator. The preliminary process configuration and its representation in ASPEN are described. As assessment of the capability of the model to mechanistically predict product stream compositions was made, and fidelity gaps and opportunities for model enhancement were identified, resulting in the following conclusions: (1) Appreciable benefit is derived from using an activity coefficient model for electrolyte solution thermodynamics rather than assuming ideality (unity assumed for all activity coefficients). The concentrations of fifteen percent of the species present in the primary output stream were changed by more than 50%, relative to Electrolyte NRTL, when ideality was assumed; (2) The current baseline model provides a good start for estimating mass balances and performing integrated process optimization because it contains several key species, uses a mechanistic electrolyte thermodynamic model, and is based on a reasonable process configuration; and (3) Appreciable improvement to model fidelity can be realized by expanding the species list and the list of chemical and phase transformations. A path forward is proposed focusing on the use of an improved electrolyte thermodynamic property method, addition of chemical and phase transformations for key species currently absent from the model, and the combination of RGibbs and Flash blocks to simulate simultaneous phase and chemical equilibria in the off-gas treatment train.
Date: August 15, 2002
Creator: Nichols, T.T.; Taylor, D.D.; Wood, R.A. & Barnes, C.M.
Partner: UNT Libraries Government Documents Department

Impact of next-generation synchrotron radiation sources on materials research.

Description: Three generations of synchrotron radiation sources have revolutionized our understanding of various correlations in the equilibrium phase of materials through x-ray imaging, spectroscopy and scattering techniques. It is anticipated that new sources based on energy-recovery linacs (ERLs) and x-ray free-electron lasers (FELs) will deliver x-ray pulses that are below a few-hundred femtoseconds in length and have very high coherence. These sources will extend and broaden our current knowledge of materials science. But more importantly, it is expected that these sources will provide the first glimpse of nonequilibrium processes in materials, including nonthermal melting, metal-insulator transitions involving nonequilibrium phases, laser-induced catalytic oxidation, and determining the structure of imperfect nanoparticles lacking crystalline structure.
Date: February 15, 2002
Creator: Shenoy, G. K.
Partner: UNT Libraries Government Documents Department

The structural failure probability analysis of pipe impact onto a concrete wall.

Description: The purpose of this study was to perform a probabilistic safety assessment of a steel pipe impacting against a concrete wall. The probabilistic structural integrity evaluation was coupled with a deterministic FE program, NEPTUNE. This evaluation included deterministic modeling, definition of random variables, description of failure criterion or limit state function, running the probabilistic analysis and reviewing the final results.
Date: May 15, 2002
Creator: Kulak, R.; Merchertas, P. & Petkevicius, K.
Partner: UNT Libraries Government Documents Department

Savings estimates for the ENERGY STAR (registered trademark) voluntary labeling program: 2001 status report

Description: ENERGY STAR(Registered Trademark) is a voluntary labeling program designed to identify and promote energy-efficient products, buildings and practices. Operated jointly by the Environmental Protection Agency (EPA) and the U.S. Department of Energy (DOE), ENERGY STAR labels exist for more than thirty products, spanning office equipment, residential heating and cooling equipment, commercial and residential lighting, home electronics, and major appliances. This report presents savings estimates for a subset of ENERGY STAR program activities, focused primarily on labeled products. We present estimates of the energy, dollar and carbon savings achieved by the program in the year 2000, what we expect in 2001, and provide savings forecasts for two market penetration scenarios for the period 2001 to 2020. The target market penetration forecast represents our best estimate of future ENERGY STAR savings. It is based on realistic market penetration goals for each of the products. We also provide a forecast under the assumption of 100 percent market penetration; that is, we assume that all purchasers buy ENERGY STAR-compliant products instead of standard efficiency products throughout the analysis period.
Date: February 15, 2002
Creator: Webber, Carrie A.; Brown, Richard E.; Mahajan, Akshay & Koomey, Jonathan G.
Partner: UNT Libraries Government Documents Department

UPDATING THE NRC GUIDANCE FOR HUMAN FACTORS ENGINEERING REVIEWS.

Description: The U.S. Nuclear Regulatory Commission (NRC) reviews the human factors engineering (HFE) aspects of nuclear plants. NUREG-0800 (Standard Review Plan), Chapter 18, ''Human Factors Engineering,'' is the principal NRC staff guidance document. Two main documents provide the review criteria to support the evaluations. The HFE Program Review Model (NUREG-0711) addresses the design process from planning to verification and validation to design implementation. The Human-System Interface Design Review Guidelines (NUREG-0700) provides the guidelines for the review of the HFE aspects of human-system interface technology, such as alarms, information systems, controls, and control room design. Since these documents were published in 1994 and 1996 respectively, they have been used by NRC staff, contractors, nuclear industry organizations, as well as by numerous organizations outside the nuclear industry. Using feedback from users and NRC research conducted in recent years, both documents have been revised and updated. This was done to ensure that they remain state-of-the-art evaluation tools for changing nuclear industry issues and emerging technologies. This paper describes the methodology used to revise and update the documents and summarizes the changes made to each and their current contents. Index Terms for this report are: Control system human factors, Ergonomics, Human factors, Nuclear power generation safety.
Date: September 15, 2002
Creator: O HARA,J.M.; BROWN,W.S.; HIGGINS,J.C.; PERSENSKY,J.J.; LEWIS,P.M. & BONGARRA,J.
Partner: UNT Libraries Government Documents Department

Interactive visualization of particle beams for accelerator design

Description: We describe a hybrid data-representation and rendering technique for visualizing large-scale particle data generated from numerical modeling of beam dynamics. The basis of the technique is mixing volume rendering and point rendering according to particle density distribution, visibility, and the user's instruction. A hierarchical representation of the data is created on a parallel computer, allowing real-time partitioning into high-density areas for volume rendering, and low-density areas for point rendering. This allows the beam to be interactively visualized while preserving the fine structure usually visible only with slow point based rendering techniques.
Date: January 15, 2002
Creator: Wilson, Brett; Ma, Kwan-Liu; Qiang, Ji & Ryne, Robert
Partner: UNT Libraries Government Documents Department

INTERNATIONAL UNION OF OPERATING ENGINEERS NATIONAL HAZMAT PROGRAM - PORTER-CABLE CIRCULAR SAW OENHP: 2001-04, VERSION A

Description: Florida International University's (FIU) Hemispheric Center for Environmental Technology (HCET) evaluated five saws for their effectiveness in cutting specially prepared fiberglass-reinforced plywood crates. These crates were built as surrogates for crates that presently hold radioactively contaminated glove boxes at the Department of Energy's (DOE) Los Alamos facility. The Porter-Cable circular saw was assessed on August 15-16, 2001 (Porter-Cable No.1 and Porter-Cable No.2, respectively). During the FIU test of efficacy, a team from the Operating Engineers National Hazmat Program (OENHP) evaluated the occupational safety and health issues associated with this technology. The Porter-Cable saw is a straightforward machine for cutting wood of varying thickness. The blade is fully guarded with a fixed upper and a lower retractable guard. The lower guard retracts as the blade engages the work piece. The unit is operated with an on/off guarded trigger switch and is supported with a handgrip mounted near the front of the saw. The saw is equipped with a directional nozzle, which aims sawdust away from the operator and the line of cut. An optional vacuum system, attached to the directional nozzle, is used to remove and collect dust. During the demonstration of Porter-Cable No.1, personal noise sampling indicated that one worker was under and one was at the Occupational Safety and Health Administration's (OSHA) Action Level of 85 decibels (dBA) with time-weighted averages (TWA's) of 82.7 and 84.6 dBA, respectively. During the demonstration of Porter-Cable No.2, however, both workers did exceed the Action Level with TWA's of 89.7 and 90.0 dBA. These data are not entirely representative as they were gathered during a simulation and not at the actual worksite. Additional sampling should be conducted on-site, but the workers should wear hearing protection until it is determined that it is no longer necessary. The total nuisance dust sample for Porter-Cable No.1 ...
Date: January 15, 2002
Partner: UNT Libraries Government Documents Department

Report on generation IV technical working group 3 : liquid metal reactors.

Description: This paper reports on the first round of R&D roadmap activities of the Generation IV (Gen IV) Technical Working Group (TWG) 3, on liquid metal-cooled reactors. Liquid metal coolants give rise to fast spectrum systems, and thus the reactor systems considered in this TWG are all fast reactors. Gas-cooled fast reactors are considered in the context of TWG 2. As is noted in other Gen IV papers, this first round activity is termed ''screening for potential'', and includes collecting the most complete set of liquid metal reactor/fuel cycle system concepts possible and evaluating the concepts against the Gen IV principles and goals. Those concepts or concept groups that meet the Gen IV principles and which are deemed to have reasonable potential to meet the Gen IV goals will pass to the next round of evaluation. Although we sometimes use the terms ''reactor'' or ''reactor system'' by themselves, the scope of the investigation by TWG 3 includes not only the reactor systems, but very importantly the closed fuel recycle system inevitably required by fast reactors. The response to the DOE Request for Information (RFI) on liquid metal reactor/fuel cycle systems from principal investigators, laboratories, corporations, and other institutions, was robust and gratifying. Thirty three liquid metal concept descriptions, from eight different countries, were ultimately received. The variation in the scope, depth, and completeness of the responses created a significant challenge for the group, but the TWG made a very significant effort not to screen out concepts early in the process.
Date: March 15, 2002
Creator: Lineberry, M. J.; Rosen, S. L. & Sagayama, Y.
Partner: UNT Libraries Government Documents Department

Developing Grid based infrastructure or climate modeling

Description: In this paper we discuss the development of a high performance climate modeling system as an example of the application of Grid based technology to climate modeling. The climate simulation system at Argonne currently includes a scientific modeling interface (Espresso) written in Java which incorporates Globus middleware to facilitate climate simulations on the Grid. The climate modeling system also includes a high performance version of MM5v3.4 modified for long climate simulations on our 512 processor Linux cluster (Chiba City), an interactive web based tool to facilitate analysis and collaboration via the web, and an enhanced version of the Cave5D software capable of visualizing large climate data sets. We plan to incorporate other climate modeling systems such as the Fast Ocean Atmosphere Model (FOAM) and the National Center for Atmospheric Research's (NCAR) Community Climate Systems Model (CCSM) within Espresso to facilitate their application on computational grids.
Date: August 15, 2002
Creator: Taylor, J.; Dvorak, M. & Mickelson, S.
Partner: UNT Libraries Government Documents Department

Wetting and interface integrity of Sn-Ag-Bi solder/Fe-42 percent Ni alloy system

Description: The wetting and interfacial integrity of lead-free Sn-Ag and Sn-Ag-Bi solders with 42 alloy (Fe-42wt percent Ni) were investigated. A tin-iron intermetallic layer formed at the interface and, during cooling, Ni3Sn4 platelets precipitated in the solder. After bonding, the Sn-3Ag joints have a eutectic microstructure, with a fine network of Ag3Sn particles surrounding large primary -Sn grains. Bismuth addition to Sn-3Ag improved wettability, but decreased the joint strength, owing to Bi segregation to the interface.
Date: January 15, 2002
Creator: Hwang, C.-W.; Suganuma, K.; Saiz, E. & Tomsia, A.P.
Partner: UNT Libraries Government Documents Department

Fernald restoration: ecologists and engineers integrate restoration and cleanup

Description: As cleanup workers excavate pits and tear down buildings at the Fernald site in southwest Ohio, site ecologists are working side-by-side to create thriving wetlands and develop the early stages of forest, prairie, and savanna ecosystems to restore natural resources that were impacted by years of site operations. In 1998, the U.S. Department of Energy-Fernald Office (DOE-FN) and its cleanup contractor, Fluor Fernald, Inc., initiated several ecological restoration projects in perimeter areas of the site (e.g., areas not used for or impacted by uranium processing or waste management). The projects are part of Fernald's final land use plan to restore natural resources over 904 acres of the 1,050-acre site. Pete Yerace, the DOE-FN Natural Resource Trustee representative is working with the Fernald Natural Resource Trustees in an oversight role to resolve the state of Ohio's 1986 claim against DOE for injuries to natural resources. Fluor Fernald, Inc., and DOE-FN developed the ''Natural Resource Restoration Plan'', which outlines 15 major restoration projects for the site and will restore injured natural resources at the site. In general, Fernald's plan includes grading to maximize the formation of wetlands or expanded floodplain, amending soil where topsoil has been removed during excavation, and establishing native vegetation throughout the site. Today, with cleanup over 35 percent complete and site closure targeted for 2006, Fernald is entering a new phase of restoration that involves heavily remediated areas. By working closely with engineers and cleanup crews, site ecologists can take advantage of remediation fieldwork (e.g., convert an excavated depression into a wetland) and avoid unnecessary costs and duplication. This collaboration has also created opportunities for relatively simple and inexpensive restoration of areas that were discovered during ongoing remediation. To ensure the survival of the plant material in heavily disturbed soils, Fernald will use techniques such as large-scale soil ...
Date: July 15, 2002
Creator: Woods, Eric & Homer, John
Partner: UNT Libraries Government Documents Department

Equilibria and Stability of JET Discharges with Zero Core Current Density

Description: Injection of Lower Hybrid Heating and Current Drive (LHCD) into the current ramp-up phase of JET [Joint European Torus] discharges can produce extremely reversed q-profiles characterized by a core region of near zero current density (within Motional Stark Effect diagnostic measurement errors). Non-inductive, off-axis co-current drive induces a back electromotive force inside the non-inductive current radius that drives a negative current in the plasma core. The core current density does not go negative, although current diffusion calculations indicate that there is sufficient LHCD to cause this. The clamping of the core current density near zero is consistent with n=0 reconnection events redistributing the core current soon after it goes negative. This is seen in reduced MHD simulations and in nonlinear resistive MHD simulations which predict that these discharges undergo n=0 reconnection events that clamp the core current near zero.
Date: October 15, 2002
Creator: Stratton, B.C.; Hawkes, N.C.; Huysmans, G.T.A.; Breslau, J.A.; Zakharov, L.E.; Alper, B. et al.
Partner: UNT Libraries Government Documents Department

MAPPING INDUCED POLARIZATION WITH NATURAL ELECTROMAGNETIC FIELDS FOR EXPLORATION AND RESOURCES CHARACTERIZATION BY THE MINING INDUSTRY

Description: The objectives of this project is to demonstrate the use of a new geophysical system to collect economically competitive induced polarization (IP) data using natural electromagnetic (EM) field as a source. The proposed technology uses naturally-existing EM fields, which provides greater depth of exploration and significant economic, energy, environmental and safety benefits.
Date: January 15, 2002
Creator: Nichols, Edward
Partner: UNT Libraries Government Documents Department

Uniaxial creep behavior of V-4Cr-4Ti alloy.

Description: We are undertaking a systematic study at Argonne National Laboratory to evaluate the uniaxial creep behavior of V-Cr-Ti alloys in a vacuum environment as a function of temperature in the range of 650-800 C and at applied stress levels of 75-380 MPa. Creep strain in the specimens is measured by a linear-variable-differential transducer, which is attached between the fixed and movable pull rods of the creep assembly. Strain is measured at sufficiently frequent intervals during testing to define the creep strain/time curve. A linear least-squares analysis function is used to ensure consistent extraction of minimum creep rate, onset of tertiary creep, and creep strain at the onset of tertiary creep. Creep test data, obtained at 650, 700, 725, and 800 C, showed power-law creep behavior. Extensive analysis of the tested specimens is conducted to establish hardness profiles, oxygen content, and microstructural characteristics. The data are also quantified by the Larson-Miller approach, and correlations are developed to relate time to rupture, onset of tertiary creep, times for 1 and 2% strain, exposure temperature, and applied stress.
Date: April 15, 2002
Creator: Natesan, K.; Soppet, W.K. & Purohit, A.
Partner: UNT Libraries Government Documents Department

Two energy scales and slow crossover in YbAl3

Description: We present results for YbAl{sub 3} which show that the susceptibility {chi}(T), 4f occupation number n{sub f}(T) and the entropy S(T) exhibit a slow crossover between the Fermi liquid and local moment regimes. In addition both {chi}(T) and the linear specific heat coefficient {gamma} = C/T exhibit low temperature peaks that imply that in addition to the Kondo scale (T{sub K} {approx} 500K) there is a second low temperature scale (T{sub coh} {approx} 50K) for the onset of coherence. We discuss these results in the context of Nozieres' exhaustion in the Anderson lattice.
Date: January 15, 2002
Creator: Lawrence, J.M.; Ebihara, T.; Riseborough, P.S.; Booth, C.H.; Pagliuso, P.G.; Sarrao, J.L. et al.
Partner: UNT Libraries Government Documents Department

Assessing U.S. ESCO industry performance and market trends: Results from the NAESCO database project

Description: The U.S. Energy Services Company (ESCO) industry is often cited as the most successful model for the private sector delivery of energy-efficiency services. This study documents actual performance of the ESCO industry in order to provide policymakers and investors with objective informative and customers with a resource for benchmarking proposed projects relative to industry performance. We have assembled a database of nearly 1500 case studies of energy-efficiency projects - the most comprehensive data set of the U.S. ESCO industry available. These projects include $2.55B of work completed by 51 ESCOs and span much of the history of this industry.
Date: May 15, 2002
Creator: Osborn, Julie; Goldman, Chuck; Hopper, Nicole & Singer, Terry
Partner: UNT Libraries Government Documents Department

Remote sensing of micrometeorological quantities.

Description: This overview of the uses of sodars in meteorological applications categorizes the applications by signal source, specifically amplitude, frequency, or ''visualization'' for example, of vertical time sections of signal amplitude. Examples are shown of data derived from each category. A final section presents the potential for using groups of sodars in networks with other instruments to estimate quantities such as divergence.
Date: May 15, 2002
Creator: Coulter, R. L.
Partner: UNT Libraries Government Documents Department