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The Evolution of Publishing Agreements at the University of Michigan

Description: Article on the evolution of publishing agreements at the University of Michigan Library. Taking as an example an open-access journal with a single editor, this article discusses the various configurations of rights agreements used by the University of Michigan Library throughout the evolution of its publishing operation, the advantages of the various models, and the reasons for moving from one to another.
Date: December 11, 2014
Creator: Hawkins, Kevin S.
Partner: UNT Libraries

Development of small, fast reactor core designs using lead-based coolant.

Description: A variety of small (100 MWe) fast reactor core designs are developed, these include compact configurations, long-lived (15-year fuel lifetime) cores, and derated, natural circulation designs. Trade studies are described which identify key core design issues for lead-based coolant systems. Performance parameters and reactivity feedback coefficients are compared for lead-bismuth eutectic (LBE) and sodium-cooled cores of consistent design. The results of these studies indicate that the superior neutron reflection capability of lead alloys reduces the enrichment and burnup swing compared to conventional sodium-cooled systems; however, the discharge fluence is significantly increased. The size requirement for long-lived systems is constrained by reactivity loss considerations, not fuel burnup or fluence limits. The derated lead-alloy cooled natural circulation cores require a core volume roughly eight times greater than conventional compact systems. In general, reactivity coefficients important for passive safety performance are less favorable for the larger, derated configurations.
Date: June 11, 1999
Creator: Cahalan, J. E.; Hill, R. N.; Khalil, H. S. & Wade, D. C.
Partner: UNT Libraries Government Documents Department

Modeling the wind-fields of accidental releases with an operational regional forecast model

Description: The Atmospheric Release Advisory Capability (ARAC) is an operational emergency preparedness and response organization supported primarily by the Departments of Energy and Defense. ARAC can provide real-time assessments of atmospheric releases of radioactive materials at any location in the world. ARAC uses robust three-dimensional atmospheric transport and dispersion models, extensive geophysical and dose-factor databases, meteorological data-acquisition systems, and an experienced staff. Although it was originally conceived and developed as an emergency response and assessment service for nuclear accidents, the ARAC system has been adapted to also simulate non-radiological hazardous releases. For example, in 1991 ARAC responded to three major events: the oil fires in Kuwait, the eruption of Mt. Pinatubo in the Philippines, and the herbicide spill into the upper Sacramento River in California. ARAC`s operational simulation system, includes two three-dimensional finite-difference models: a diagnostic wind-field scheme, and a Lagrangian particle-in-cell transport and dispersion scheme. The meteorological component of ARAC`s real-time response system employs models using real-time data from all available stations near the accident site to generate a wind-field for input to the transport and dispersion model. Here we report on simulation studies of past and potential release sites to show that even in the absence of local meteorological observational data, readily available gridded analysis and forecast data and a prognostic model, the Navy Operational Regional Atmospheric Prediction System, applied at an appropriate grid resolution can successfully simulate complex local flows.
Date: September 11, 1995
Creator: Albritton, J.R.; Lee, R.L. & Sugiyama, G.
Partner: UNT Libraries Government Documents Department

Phosphate ceramic solidification and stabilization of cesium-containing crystalline silicotitanate resins.

Description: This paper reports on the fabrication and testing of magnesium potassium phosphate (MKP)-bonded cesium-loaded crystalline silicotitanate (CST) resins. Typical waste loading of CST resins in the final waste forms was 50 wt.%. Physical and chemical characterization of the MKP materials has shown them to be physically, chemically, and mineralogically stable. Long-term durability studies (using the AN 16.1 standard test) showed a leachability index of {approx}18 for cesium in the phosphate matrix when exposed to deionized water under ambient and elevated temperatures. Leaching of cesium was somewhat higher than in glass waste forms as per PCT and MCC-1 tests. MKP-based final waste forms showed no significant weight changes after exposure to aqueous media for {approx}90 days, indicating the highly insoluble nature of the phosphate matrix. In addition, durability of the CST-MKP waste forms was further established by freeze-thaw cycling tests.
Date: May 11, 1999
Creator: Langton, C. A.
Partner: UNT Libraries Government Documents Department

Initial generation and separation of {sup 99}Mo at Sandia National Laboratories

Description: Medical isotopes play an important role in the medical industry in both the United States and the world. Isotopes such as {sup 99}Tc, {sup 201}Tl, {sup 111}In, and {sup 123}I are utilized in diagnostic imaging studies, while others such as {sup 131}I and {sup 89}Sr are used as therapeutic agents. The particular medical isotope {sup 99m}Tc is used in 80% of all nuclear medical procedures in the United States. This isotope is produced from the decay of {sup 99}Mo, which has a 66 hour half-life. The importance of {sup 99m}Tc and the fact of its 6 hour half-life indicate the necessity to maintain a constant supply of {sup 99}Mo. The most prominent method for the production of significant quantities of {sup 99}Mo is by fission in highly-enriched uranium loaded targets. This paper describes the work performed at SNL for the production of {sup 99}Mo.
Date: April 11, 1997
Creator: Talley, D.G.; Bourcier, S.C.; McDonald, M.J.; Longley, S.W. & Parma, E.J.
Partner: UNT Libraries Government Documents Department

Ligand-Thickness Effect Leads to Enhanced Preference for Large Anions in Alkali Metal Extraction by Crown Ethers

Description: Jean-Marie Lehn (Nobel laureate, 1987) suggested ligand thickness to be an important consideration in the design of host molecules for cation recognition. We have recently expanded the role of this simple ligand property by demonstrating a case in which ligand thickness contributes significantly to anion discrimination. It was found that in the extraction of sodium nitrate and perchlorate by a simple crown ether, bis(t-octylbenzo)-14-crown-4 (BOB 14C4), the normal preference for perchlorate is almost completely lost when the complex cation has the open-face sandwich vs. the sandwich structure.
Date: July 11, 1999
Creator: Haverlock, T.J.; Moyer, B.A. & Sachleben, R.A.
Partner: UNT Libraries Government Documents Department

Geothermal high temperature instrumentation applications

Description: A quick look at the geothermal industry shows a small industry producing about $1 billion in electric sales annually. The industry is becoming older and in need of new innovative solutions to instrumentation problems. A quick look at problem areas is given along with basic instrumentation requirements. The focus of instrumentation is on high temperature electronics.
Date: June 11, 1998
Creator: Normann, R.A. & Livesay, B.J.
Partner: UNT Libraries Government Documents Department

Control system for BCP processing facility at FNAL

Description: The surface processing is one of the key elements of superconducting RF cavity fabrication. Safety and reliability are the main requirements for the chemical surface treatment facility being developed at FNAL. Accepting the Buffered Chemical Polishing (BCP) as the baseline process, a ''gravity feed and open etching tank'' approach has been chosen at this stage. This choice resulted in the introduction of a control system with a strong automation since the number of elements to be controlled at different steps of the process is rather big. In order to allow for maximum flexibility, two operational modes were defined within the control system: semi-automatic, which requires an operator's decision to move from one stage to another, and manual. This paper describes the main features of the control system for the BCP facility that is under development at FNAL.
Date: September 11, 2003
Creator: al., Cristian Boffo et
Partner: UNT Libraries Government Documents Department

Serving database information using a flexible server in a three tier architecture

Description: The D0 experiment at Fermilab relies on a central Oracle database for storing all detector calibration information. Access to this data is needed by hundreds of physics applications distributed worldwide. In order to meet the demands of these applications from scarce resources, we have created a distributed system that isolates the user applications from the database facilities. This system, known as the Database Application Network (DAN) operates as the middle tier in a three tier architecture. A DAN server employs a hierarchical caching scheme and database connection management facility that limits access to the database resource. The modular design allows for caching strategies and database access components to be determined by runtime configuration. To solve scalability problems, a proxy database component allows for DAN servers to be arranged in a hierarchy. Also included is an event based monitoring system that is currently being used to collect statistics for performance analysis and problem diagnosis. DAN servers are currently implemented as a Python multithreaded program using CORBA for network communications and interface specification. The requirement details, design, and implementation of DAN are discussed along with operational experience and future plans.
Date: August 11, 2003
Creator: al., Lee Lueking et
Partner: UNT Libraries Government Documents Department

Development of Chemical Treatment Alternatives for Tetraphenylborate Destruction in Tank 48H

Description: This study assessed chemical treatment options for decomposing the tetraphenylborate in High Level Waste (HLW) Tank 48H. Tank 48H, located at the Savannah River Site in Aiken, SC, contains approximately one million liters of HLW. The tetraphenylborate slurry represents legacy material from commissioning of an In Tank Precipitation process to separate radioactive cesium and actinides from the nonradioactive chemicals. During early operations, the process encountered an unplanned chemical reaction that catalytically decomposed the excess tetraphenylborate producing benzene. Subsequent research indicated that personnel could not control the operations within the existing equipment to both meet the desired treatment rate for the waste and maintain the benzene concentration within allowable concentrations. Since then, the Department of Energy selected an alternate treatment process for handling high-level waste at the site. However, the site must destroy the tetraphenylborate before returning the tank to HLW service. The research focuses on identifying treatments to decompose tetraphenylborate to the maximum extent feasible, with a preference for decomposition methods that produce carbon dioxide rather than benzene. A number of experiments examined whether the use of oxidants, catalysts or acids proved effective in decomposing the tetraphenylborate. Additional experiments developed an understanding of the solid, liquid and gas decomposition products.
Date: March 11, 2003
Creator: Lambert, D.P.
Partner: UNT Libraries Government Documents Department

California climate change, hydrologic response, and flood forecasting

Description: There is strong evidence that the lower atmosphere has been warming at an unprecedented rate during the last 50 years, and it is expected to further increase at least for the next 100 years. Warmer air mass implies a higher capacity to hold water vapor and an increased likelihood of an acceleration of the global water cycle. This acceleration is not validated and considerable new research has gone into understanding aspects of the water cycle (e.g. Miller et al. 2003). Several significant findings on the hydrologic response to climate change can be reported. It is well understood that the observed and expected warming is related to sea level rise. In a recent seminar at Lawrence Berkeley National Laboratory, James Hansen (Director of the Institute for Space Studies, National Aeronautics and Space Administration) stressed that a 1.25 Wm{sup -2} increase in radiative forcing will lead to an increase in the near surface air temperature by 1 C. This small increase in temperature from 2000 levels is enough to cause very significant impacts to coasts. Maury Roos (Chief Hydrologist, California Department of Water Resources) has shown that a 0.3 m rise in sea level shifts the San Francisco Bay 100-year storm surge flood event to a 10-year event. Related coastal protection costs for California based on sea level rise are shown. In addition to rising sea level, snowmelt-related streamflow represents a particular problem in California. Model studies have indicated that there will be approximately a 50% decrease in snow pack by 2100. This potential deficit must be fully recognized and plans need to be put in place well in advance. In addition, the warmer atmosphere can hold more water vapor and result in more intense warm winter-time precipitation events that result in flooding. During anticipated high flow, reservoirs need to release water ...
Date: November 11, 2003
Creator: Miller, Norman L.
Partner: UNT Libraries Government Documents Department

Fireside corrosion of alloys for combustion power plants.

Description: A program on fireside corrosion is being conducted at Argonne National Laboratory to evaluate the performance of several structural alloys in the presence of mixtures of synthetic coal ash, alkali sulfates, and alkali chlorides. Candidate alloys are also exposed in a small-scale coal-fired combustor at the National Energy Technology Laboratory in Pittsburgh. Experiments in the present program, which addresses the effects of deposit chemistry, temperature, and alloy chemistry on the corrosion response of alloys, were conducted at temperatures in the range of 575-800 C for time periods up to {approx}1850 h. Alloys selected for the study included HR3C, 310TaN, HR120, SAVE 25, NF709, modified 800, 347HFG, and HCM12A. In addition, 800H clad with Alloy 671 was included in several of the exposures. Data were obtained on weight change, scale thickness, internal penetration, microstructural characteristics of corrosion products, mechanical integrity, and cracking of scales. Results showed that relationship of corrosion rates to temperature followed a bell-shaped curve, with peak rates at {approx}725 C, but the rate itself was dependent on the alloy chemistry. Several alloys showed acceptable rates in the sulfate-containing coal-ash environment; but NaCl in the deposit led to catastrophic corrosion at 650 and 800 C.
Date: June 11, 2002
Creator: Natesan, K.; Purohit, A. & Rink, D. L.
Partner: UNT Libraries Government Documents Department

Comparison of the Crevice Corrosion Resistance of Alloys 625 and C22

Description: The effects of electrolyte composition and oxide film age on the crevice corrosion properties of alloys 625 and C22 were studied at 95 C. Critical potentials were determined using conventional current density thresholds. Crevice stabilization potentials are influenced by the bulk electrolyte composition, oxide properties, and alloy dissolution behavior. Repassivation and deactivation potentials are controlled by the chemistry of the crevice solution, mass transport considerations, and the electrochemical properties of the alloys. Critical potential data also showed the large influence of air formed oxide film age on stabilization. Air aged C22 specimens exhibited the highest resistance to crevice corrosion in terms of critical crevice potentials, while freshly polished C22 exhibited the lowest resistance.
Date: November 11, 1999
Creator: Kehler, B.A.; Ilevbare, G.O. & Scully, J.R.
Partner: UNT Libraries Government Documents Department

The scaling relationship between self-potential and fluid flow on Masaya volcano, Nicaragua

Description: The concurrent measurement of self-potential (SP) and soil CO{sub 2} flux (F{sub s}{sup CO2}) in volcanic systems may be an important tool to monitor intrusive activity and understand interaction between magmatic and groundwater systems. However, quantitative relationships between these parameters must be established to apply them toward understanding processes operating at depth. Power-law scaling exponents calculated for SP and F{sub s}{sup CO2} measured along a fault on the flanks of Masaya volcano, Nicaragua indicate a nonlinear relationship between these parameters. Scaling exponents suggest that there is a declining increase in SP with a given increase in F{sub s}{sup CO2}, until a threshold (log F{sub s}{sup CO2} {approx} 2.5 g m{sup -2}d{sup -1}) above which SP remains constant with increasing F{sub s}{sup CO2}. Implications for subsurface processes that may influence SP at Masaya are discussed.
Date: November 11, 2003
Creator: Lewicki, J. L.; Hilley, G. E. & Conner, C.
Partner: UNT Libraries Government Documents Department

Macro and Micro Remote Viewing of Objects in Sealed Gloveboxes

Description: The Savannah River Site uses sophisticated glovebox facilities to process and analyze material that is radiologically contaminated or that must be protected from contamination by atmospheric gases. The analysis can be visual, non destructive measurement, or destructive measurement, and allows for the gathering of information that would otherwise not be obtainable. Macro and Micro systems that cover a range of 2X to 400X magnifications with a robust system compatible with the harsh glovebox environment were installed. Remote video inspection systems were developed and deployed in Savannah River Site glovebox facilities that provide high quality or mega-pixel quality remote views, for remote inspections. The specialized video systems that are the subject of this report exhibited specialized field application of remote video/viewing techniques by expanding remote viewing to high and very high quality viewing in gloveboxes. This technological enhancement will allow the gathering of precision information that is otherwise not available.
Date: February 11, 2004
Creator: Heckendorn, F.M.
Partner: UNT Libraries Government Documents Department

Catalytic autothermal reforming of hydrocarbon fuels for fuel cells.

Description: Fuel cell development has seen remarkable progress in the past decade because of an increasing need to improve energy efficiency as well as to address concerns about the environmental consequences of using fossil fuel for producing electricity and for propulsion of vehicles [1]. The lack of an infrastructure for producing and distributing H{sub 2} has led to a research effort to develop on-board fuel processing technology for reforming hydrocarbon fuels to generate H{sub 2} [2]. The primary focus is on reforming gasoline, because a production and distribution infrastructure for gasoline already exists to supply internal combustion engines [3]. Existing reforming technology for the production of H{sub 2} from hydrocarbon feedstocks used in large-scale manufacturing processes, such as ammonia synthesis, is cost prohibitive when scaled down to the size of the fuel processor required for transportation applications (50-80 kWe) nor is it designed to meet the varying power demands and frequent shutoffs and restarts that will be experienced during normal drive cycles. To meet the performance targets required of a fuel processor for transportation applications will require new reforming reactor technology developed to meet the volume, weight, cost, and operational characteristics for transportation applications and the development of new reforming catalysts that exhibit a higher activity and better thermal and mechanical stability than reforming catalysts currently used in the production of H{sub 2} for large-scale manufacturing processes.
Date: January 11, 2002
Creator: Krumpelt, M.; Krause, T.; Kopasz, J.; Carter, D. & Ahmed, S.
Partner: UNT Libraries Government Documents Department

HYDROGEN OUTGASSING AND SURFACE PROPERTIES OF TIN COATED STAINLESS STEEL CHAMBERS.

Description: The stainless steel vacuum chambers of the 248m accumulator ring of Spallation Neutron Source (SNS) are coated with {approx} 100 nm of titanium nitride (TiN) to reduce the secondary electron yield. The coating is produced by DC magnetron sputtering using a long cathode imbedded with permanent magnets. The outgassing rates of several SNS half-cell chambers were measured with and without TiN coating, and before and after in-situ bake. One potential benefit of a TiN coating is to serve as hydrogen permeation barrier that reduces the ultimate outgassing rate. By varying the coating parameters, films of different surface roughness were produced and analyzed by Auger electron spectroscopy, scanning electron microscopy and atomic force microscopy to illustrate the dependence of the outgassing on the film structure.
Date: November 11, 2002
Creator: HE,P.; HSEUH,H.C.; MAPES,M.; TODD,R.; WEISS,D. & WILSON,D.
Partner: UNT Libraries Government Documents Department

Examination of spent PWR fuel rods after 15 years in dry storage.

Description: Virginia Power Surry Nuclear Station Pressurized Water Reactor (PWR) fuel was stored in a dry inert atmosphere Castor V/21 cask at the Idaho National Environmental and Engineering Laboratory (INEEL) for 15 years at peak cladding temperatures decreasing from about 350 to 150 C. Prior to the storage, the loaded cask was subjected to extensive thermal benchmark tests. The cask was opened to examine the fuel for degradation and to determine if it was suitable for extended storage. No rod breaches had occurred and no visible degradation or crud/oxide spallation were observed. Twelve rods were removed from the center of the T11 assembly and shipped from INEEL to the Argonne-West HFEF for profilometric scans. Four of these rods were punctured to determine the fission gas release from the fuel matrix and internal pressure in the rods. Three of the four rods were cut into five segments each, then shipped to the Argonne-East AGHCF for detailed examination. The test plan calls for metallographic examination of six samples from two of the rods, microhardness and hydrogen content measurements at or near the six metallographic sample locations, tensile testing of six samples from the two rods, and thermal creep testing of eight samples from the two rods to determine the extent of residual creep life. The results from the profilometry (12 rods), gas release measurements (4 rods), metallographic examinations (2 samples from 1 rod), and microhardness and hydrogen content characterization (2 samples from 1 rod) are reported here. The tensile and creep studies are just starting and will be reported at a later date, along with the additional characterization work to be performed. Although only limited prestorage characterization is available, a number of preliminary conclusions can be drawn based on comparison with characterization of Florida Power Turkey Point rods of a similar vintage. Based ...
Date: February 11, 2002
Creator: Einziger, R. E.; Tsai, H. C.; Billone, M. C. & Hilton, B. A.
Partner: UNT Libraries Government Documents Department

Strategies for cost-effective carbon reductions: A sensitivity analysis of alternative scenarios

Description: Analyses of alternative futures often present results for a limited set of scenarios, with little if any sensitivity analysis to identify the factors affecting the scenario results. This approach creates an artificial impression of certainty associated with the scenarios considered, and inhibits understanding of the underlying forces. This paper summarizes the economic and carbon savings sensitivity analysis completed for the Scenarios for a Clean Energy Future study (IWG, 2000). Its 19 sensitivity cases provide insight into the costs and carbon-reduction impacts of a carbon permit trading system, demand-side efficiency programs, and supply-side policies. Impacts under different natural gas and oil price trajectories are also examined. The results provide compelling evidence that policy opportunities exist to reduce carbon emissions and save society money.
Date: July 11, 2001
Creator: Gumerman, Etan; Koomey, Jonathan G. & Brown, Marilyn
Partner: UNT Libraries Government Documents Department

Beauty, charm and hyperon production at fixed-target experiments

Description: Over the years fixed-target experiments have performed numerous studies of particle production in strong interactions. The experiments have been performed with different types of beam particles of varying energies, and many different target materials. Since the physics of particle production is still not understood, ongoing research of phenomena that we observe as beauty, charm and strange-particle production is crucial if we are to gain an understanding of these fundamental processes. It is in this context that recent results from fixed-target experiments on beauty, charm, and hyperon production will be reviewed.
Date: December 11, 2002
Creator: Gottschalk, Erik
Partner: UNT Libraries Government Documents Department