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Workshop report - Bridging the Climate Information held at Argonne National Laboratory September 29, 1999 (open access)

Workshop report - Bridging the Climate Information held at Argonne National Laboratory September 29, 1999

In a recent report entitled The Regional Impacts of Climate Change it was concluded that the technological capacity to adapt to climate change is likely to be readily available in North America, but its application will be realized only if the necessary information is available (sufficiently far in advance in relation to the planning horizons and lifetimes of investments) and the institutional and financial capacity to manage change exists. The report also acknowledged that one of the key factors that limit the ability to understand the vulnerability of subregions of North America to climate change, and to develop and implement adaptive strategies to reduce that vulnerability, is the lack of accurate regional projections of climate change, including extreme events. In particular, scientists need to account for the physical-geographic characteristics (e.g., the Great Lakes, coastlines, and mountain ranges) that play a significant role in the North America climate and also need to consider the feedback between the biosphere and atmosphere.
Date: March 10, 2000
Creator: Taylor, J.
System: The UNT Digital Library
Fusion option to dispose of spent nuclear fuel and transuranic elements (open access)

Fusion option to dispose of spent nuclear fuel and transuranic elements

The fusion option is examined to solve the disposition problems of the spent nuclear fuel and the transuranic elements. The analysis of this report shows that the top rated solution, the elimination of the transuranic elements and the long-lived fission products, can be achieved in a fusion reactor. A 167 MW of fusion power from a D-T plasma for sixty years with an availability factor of 0.75 can transmute all the transuranic elements and the long-lived fission products of the 70,000 tons of the US inventory of spent nuclear fuel generated up to the year 2015. The operating time can be reduced to thirty years with use of 334 MW of fusion power, a system study is needed to define the optimum time. In addition, the fusion solution eliminates the need for a geological repository site, which is a major advantage. Meanwhile, such utilization of the fusion power will provide an excellent opportunity to develop fusion energy for the future. Fusion blankets with a liquid carrier for the transuranic elements can achieve a transmutation rate for the transuranic elements up to 80 kg/MW.y of fusion power with k{sub eff} of 0.98. In addition, the liquid blankets have several advantages relative …
Date: February 10, 2000
Creator: Gohar, Y.
System: The UNT Digital Library
Hanford Site Groundwater Monitoring for Fiscal Year 1999 (open access)

Hanford Site Groundwater Monitoring for Fiscal Year 1999

This report presents the results of groundwater and vadose zone monitoring and remediation for fiscal year 1999 on the US. Department of Energy's Hanford Site, Washington. Water-level monitoring was performed to evaluate groundwater flow directions, to track changes in water levels, and to relate such changes to evolving disposal practices. Measurements for site-wide maps were conducted in June in past years and are now measured in March to reflect conditions that are closer to average. Water levels over most of the Hanford Site continued to decline between June 1998 and March 1999. The most widespread radiological contaminant plumes in groundwater were tritium and iodine-129. Concentrations of carbon-14, strontium-90, technetium-99, and uranium also exceeded drinking water standards in smaller plumes. Cesium-137 and plutonium exceeded standards only near the 216-B-5 injection well. Derived concentration guide levels specified in US Department of Energy Order 5400.5 were exceeded for plutonium, strontium-90, tritium, and uranium in small plumes or single wells. Nitrate and carbon tetrachloride are the most extensive chemical contaminants. Chloroform, chromium, cis-1,2dichloroethylene, cyanide, fluoride, and trichloroethylene also were present in smaller areas at levels above their maximum contaminant levels. Metals such as aluminum, cadmium, iron, manganese, and nickel exceeded their maximum contaminant levels …
Date: May 10, 2000
Creator: Hartman, MJ; Morasch, LF & Webber, WD
System: The UNT Digital Library
Hydrolysis of late-washed, irradiated tetraphenylborate slurry simulants I: Phenylboric acid hydrolysis kinetics (open access)

Hydrolysis of late-washed, irradiated tetraphenylborate slurry simulants I: Phenylboric acid hydrolysis kinetics

The attached report details the kinetics of phenylboric acid reaction at 90 degrees C during precipitate hydrolysis processing of late-washed, irradiated tetraphenylborate slurry simulants.
Date: February 10, 2000
Creator: Marek, J.C.
System: The UNT Digital Library
The Fermilab computing farms in 1999 (open access)

The Fermilab computing farms in 1999

The farms in 1999 changed in two major ways. First, PC's running Linux continued to expand and this allowed for the reduction of the SGI and IBM components of the farms. Second, the first large farms for CDF and D0 Run II were purchased and installed in 1999. Simultaneously, a large increment for non-Run II computing was made. The farms continue to provide large CPU resources for those experiments and calculations which benefit from this type of computing (large CPU, low I/O, dedicated resources). Farms usage will continue to increase given the demands of the user community (reflecting the scientific program) and the preparation for and beginning of Run II.
Date: May 10, 2000
Creator: al., Marina Albert et
System: The UNT Digital Library
Fractured petroleum reservoirs (open access)

Fractured petroleum reservoirs

Total compressibility in a fractured reservoir is estimated using the pressure response due to gravitational potential variations. Both the moon and the sun gravitational potentials are accounted for using the full expression by inclusion of longer-period components. The semi-diurnal and diurnal pressure data show substantial long-term variations. The gravitational potential also contains the same variation trend; the ratio between the potential and pressure has a fairly uniform value over successive cycles. The computed total compressibility is also fairly constant and independent of the cycle. Results show the effects of the time interval over which the pressure measurements are performed as well as the location.
Date: January 10, 2000
Creator: Firoozabadi, A.; Chang, E. & Tang, G.Q.
System: The UNT Digital Library
Studies of Radiation-Produced Radicals and Radical Ions. Final technical report, July 15, 1994 to December 14, 1999 (open access)

Studies of Radiation-Produced Radicals and Radical Ions. Final technical report, July 15, 1994 to December 14, 1999

None
Date: March 10, 2000
Creator: Williams, T. Ffrancon
System: The UNT Digital Library
Second ILAW Site Borehole Characterization Plan (open access)

Second ILAW Site Borehole Characterization Plan

This plan describes the characterization work that will be preformed on the second borehole to be drilled in support of the Immobilized Low-Activity Waste Performance Assessment
Date: August 10, 2000
Creator: Reidel, Steve
System: The UNT Digital Library
Molecular mechanisms controlling proton pumping by bacteriorhodopsin. Final report (open access)

Molecular mechanisms controlling proton pumping by bacteriorhodopsin. Final report

Bacteriorhodopsin (bR) is the simplest biological system for the transduction of light energy. Light energy is directly converted to transmembrane proton gradient by a single, small membrane protein. The extraordinary stability of bR makes it an outstanding subject for bioenergetic studies. This project has focused on the role of interactions between key residues of the pigment involved in light-induced proton transfer. Methods to estimate the strength of these interactions and their correlation with the rate and efficiency of proton transfer have been developed. The concept of the coupling of the protonation states of key groups has been applied to individual steps of the proton transfer with the ultimate goal of understanding on the molecular level the driving forces for proton transport and the pathway of the transported proton in bT. The mechanism of light-induced proton release, uptake and the mechanism of recovery of initial state of bT has been examined. The experiments were performed with genetically engineered, site-specific mutants of bR. This has enabled us to characterize the role of individual amino acid residues in bR. Time resolved and low temperature absorption spectroscopy and light-induced photocurrent measurements were used in order to study the photochemical cycle and proton transfer in …
Date: February 10, 2000
Creator: Crouch, Rosalie K. & Ebrey, Thomas G.
System: The UNT Digital Library
China energy, environment, and climate study: Background issues paper (open access)

China energy, environment, and climate study: Background issues paper

The total costs and impacts of expanding energy use in China will depend, in part, on a number of important factors, an understanding of which is vital for China's policy-makers. These issues include the additional environmental and public health impacts associated with energy use, the economic costs of infrastructure expansion to meet growing energy needs, and the potential role that renewable energy technologies could play if pushed hard in China's energy future. This short report summarizes major trends and issues in each of these three areas.
Date: October 10, 2000
Creator: Sinton, Jonathan E.; Fridley, David G.; Logan, Jeffrey; Guo, Yuan; Wang, Bangcheng & Xu, Qing
System: The UNT Digital Library
The potential for buoyant displacement gas release events in Tank 241-SY-102 after waste transfer from Tank 241-SY-101 (open access)

The potential for buoyant displacement gas release events in Tank 241-SY-102 after waste transfer from Tank 241-SY-101

Tank 241-SY-101 (SY-101) is a double-shell, radioactive waste storage tank with waste that, before the recent transfer and water back-dilution operations, was capable of retaining gas and producing buoyant displacement (BD) gas release events (GREs). Some BD GREs caused gas concentrations in the tank headspace to exceed the lower flammability limit (LFL). A BD GRE occurs when a portion of the nonconvective layer retains enough gas to become buoyant, rises to the waste surface, breaks up, and releases some of its stored gas. The installation of a mixer pump in 1993 successfully mitigated gas retention in the settled solids layer in SY-101 and has since prevented BD GREs. However, operation of the mixer pump over the years caused gas retention in the floating crust layer and a corresponding accelerated waste level growth. The accelerating crust growth trend observed in 1997--98 led to initiation of sequences of waste removal and water back-dilutions in December 1999. Waste is removed from the mixed slurry layer in Tank SY-101 and transferred into Tank 241-Sy-102 (SY-102). Water is then added back to dissolve soluble solids that retain gas. The initial transfer of 89,500 gallons of SY-101 waste, diluted in-line at 0.94:1 by volume with water, …
Date: May 10, 2000
Creator: Wells, B. E.; Meyer, P. A. & Chen, G.
System: The UNT Digital Library
Second ILAW Site Borehole Characterization Plan (open access)

Second ILAW Site Borehole Characterization Plan

The US Department of Energy's Hanford Site has the most diverse and largest amounts of radioactive tank waste in the US. High-level radioactive waste has been stored at Hanford since 1944. Approximately 209,000 m{sup 3} (54 Mgal) of waste are currently stored in 177 tanks. Vitrification and onsite disposal of low-activity tank waste (LAW) are embodied in the strategy described in the Tri-Party Agreement. The tank waste is to be retrieved, separated into low- and high-level fractions, and then immobilized. The low-activity vitrified waste will be disposed of in the 200 East Area of the Hanford Site. This report is a plan to drill and characterize the second borehole for the Performance Assessment. The first characterization borehole was drilled in 1998. The plan describes data collection activities for determining physical and chemical properties of the vadose zone and saturated zone on the northeast side of the proposed disposal site. These data will then be used in the 2005 Performance Assessment.
Date: August 10, 2000
Creator: Valenta, M. M.; Moreno, J. R.; Martin, M. B.; Ferri, R. E.; Houston, D. G. & Reidel, S. P.
System: The UNT Digital Library
Population Characteristics and Seasonal Movement Patterns of the Rattlesnake Hills Elk Herd - Status Report 2000 (open access)

Population Characteristics and Seasonal Movement Patterns of the Rattlesnake Hills Elk Herd - Status Report 2000

Wildlife biologists documented an isolated elk population in 1972 on the U.S. Department of Energy's (DOE) Hanford Site. Since then the herd has grown, exceeding 800 animals in 1999. Limited harvests on adjacent private lands have occurred since 1986. The large herd size coupled with limited annual harvest have increased concerns about private land crop damages, vehicle collisions, degradation of the native environment, and the herd's use of radiologically controlled areas on the Hanford Site. As a result, in 1999, a decision was made by the Washington Department of Fish and Wildlife (WDFW) (animal management), the U.S. Fish and Wildlife Service (USFWS) (land management), and DOE (landowner) to conduct a large-scale animal roundup to remove elk from the DOE-owned lands and relocate them to distant areas within Washington State. The interagency roundup and relocation occurred in spring 2000. This report presents the current status of the herd size and composition, annual removal estimates, and some limited seasonal area-use patterns by several radio-collared elk subsequent to the large-scale elk roundup. The elk herd maintained an approximate 25% annual increase until 2000. A large harvest offsite in 1999 coupled with the large-scale roundup in spring 2000 reduced herd size to the current …
Date: October 10, 2000
Creator: Tiller, Brett L; Cadwell, Larry L; Zufelt, Rhett K; Turner, Scott D & Turner, Gerald K
System: The UNT Digital Library
PVMaT improvements in the Solarex photovoltaic module manufacturing technology: Annual subcontract report: May 5, 1998 -- April 30, 1999 (open access)

PVMaT improvements in the Solarex photovoltaic module manufacturing technology: Annual subcontract report: May 5, 1998 -- April 30, 1999

This report describes work done by Solarex during the first year of this subcontract. The objective of this three-year PVMaT program is to continue the advancement of Solarex PV manufacturing technologies to design and implement a process that produces polycrystalline silicon PV modules that can be sold profitably for $2.00 per peak watt or less and that will increase the production capacity of the Frederick plant to at least 25 megawatts per year. Accomplishments during the first year of the program include: (1) Verification of the process to produce SiF{sub 4}, the precursor to silicon feedstock. (2) Design of a silicon feedstock pilot facility using the SiNaF process. (3) Development of and transfer to manufacturing of a process to use thinner wire in the wire saw. (4) Completion of a production trial with recycled SiC. (5) Laboratory development of a selective emitter process using rapid thermal processing. (6) Fabrication of high-efficiency polycrystalline cells using silicon nitride from three different sources. (7) Development of a new encapsulation formulation and laboratory demonstration of a 6-minute lamination cycle. (8) Implementation of an automated laminator. (9) Laboratory demonstration of automated handling of ceramics.
Date: January 10, 2000
Creator: Wohlgemuth, J.
System: The UNT Digital Library
Organic carbon burial in the Cape Hatteras ocean margins. Relationships with mineral surfaces (open access)

Organic carbon burial in the Cape Hatteras ocean margins. Relationships with mineral surfaces

This project examined controls on organic carbon preservation in ocean margin sediments around Cape Hatteras, USA. Grain size variation explained most variance in sedimentary organic carbon concentrations. Normalizing to grain surface areas allowed identification of areas of particularly high organic matter loading - i.e., the upper slope regions. Spatial variations in concentrations are influenced by redistribution of organoclay aggregates. This region has higher grain size-normalized organic carbon concentrations than any other ocean margin environment with an aerobic water column studied to date. Small scale variations in the Chesapeake Bay were also studied.
Date: February 10, 2000
Creator: Mayer, Lawrence M.
System: The UNT Digital Library
COPS: Large-scale nonlinearly constrained optimization problems (open access)

COPS: Large-scale nonlinearly constrained optimization problems

The authors have started the development of COPS, a collection of large-scale nonlinearly Constrained Optimization Problems. The primary purpose of this collection is to provide difficult test cases for optimization software. Problems in the current version of the collection come from fluid dynamics, population dynamics, optimal design, and optimal control. For each problem they provide a short description of the problem, notes on the formulation of the problem, and results of computational experiments with general optimization solvers. They currently have results for DONLP2, LANCELOT, MINOS, SNOPT, and LOQO.
Date: February 10, 2000
Creator: Bondarenko, A. S.; Bortz, D. M. & More, J. J.
System: The UNT Digital Library
Multi Canister Overpack (MCO) Combustible Gas Management Leak Test Acceptance Criteria (OCRWM) (open access)

Multi Canister Overpack (MCO) Combustible Gas Management Leak Test Acceptance Criteria (OCRWM)

The purpose of this document is to support the Spent Nuclear Fuel Project's combustible gas management strategy while avoiding the need to impose any requirements for oxygen free atmospheres within storage tubes that contain multi-canister overpacks (MCO). In order to avoid inerting requirements it is necessary to establish and confirm leak test acceptance criteria for mechanically sealed and weld sealed MCOs that are adequte to ensure that, in the unlikely event the leak test results for any MCO were to approach either of those criteria, it could still be handled and stored in stagnant air without compromising the SNF Project's overall strategy to prevent accumulation of combustible gas mixtures within MCOs or within their surroundings. To support that strategy, this document: (1) establishes combustible gas management functions and minimum functional requirements for the MCO's mechanical seals and closure weld(s); (2) establishes a maximum practical value for the minimum required initial MCO inert backfill gas pressure; and (3) based on items 1 and 2, establishes and confirms leak test acceptance criteria for the MCO's mechanical seal and final closure weld(s).
Date: October 10, 2000
Creator: SHERRELL, D.L.
System: The UNT Digital Library
Gas Composition Transients in the Cold Vacuum Drying (CVD) Facility (open access)

Gas Composition Transients in the Cold Vacuum Drying (CVD) Facility

The purpose of this document is to evaluate selected problems involving the prediction of transient gas compositions during Cold Vacuum Drying operations. The problems were evaluated to answer specific design questions. The document is formatted as a topical report with each section representing a specific problem solution. The problem solutions are reported in the calculation format specified in HNF-1613, Rev. 0, EP 7.6.
Date: May 10, 2000
Creator: Packer, M. J.
System: The UNT Digital Library
Open Source Software Licenses for Livermore National Laboratory (open access)

Open Source Software Licenses for Livermore National Laboratory

This paper attempts to develop supporting material in an effort to provide new options for licensing Laboratory-created software. Where employees and the Lab wish to release software codes as so-called ''Open Source'', they need, at a minimum, new licensing language for their released products. Several open source software licenses are reviewed to understand their common elements, and develop recommendations regarding new language.
Date: August 10, 2000
Creator: Busby, L.
System: The UNT Digital Library
Laser Guide Star Based Astrophysics at Lick Observatory (open access)

Laser Guide Star Based Astrophysics at Lick Observatory

The resolution of ground-based telescopes is typically limited to {approx}1 second of arc because of the blurring effects of atmospheric turbulence. Adaptive optics (AO) technology senses and corrects for the optical distortions due to turbulence hundreds of times per second using high-speed sensors, computers, deformable mirror, and laser technology. The goal of this project is to make AO systems widely useful astronomical tools providing resolutions up to an order of magnitude better than current, ground-based telescopes. Astronomers at the University of California Lick Observatory at Mt. Hamilton now routinely use the LLNL developed AO system for high resolution imaging of astrophysical objects. We report here on the instrument development progress and on the science observations made with this system during this 3-year ERI project.
Date: March 10, 2000
Creator: Max, C; Gavel, D.; Friedman, H.; Olivier, S.; Macintosh, B.; Brase, J. et al.
System: The UNT Digital Library
Modeling and Computer Simulation: Molecular Dynamics and Kinetic Monte Carlo (open access)

Modeling and Computer Simulation: Molecular Dynamics and Kinetic Monte Carlo

Recent years have witnessed tremendous advances in the realistic multiscale simulation of complex physical phenomena, such as irradiation and aging effects of materials, made possible by the enormous progress achieved in computational physics for calculating reliable, yet tractable interatomic potentials and the vast improvements in computational power and parallel computing. As a result, computational materials science is emerging as an important complement to theory and experiment to provide fundamental materials science insight. This article describes the atomistic modeling techniques of molecular dynamics (MD) and kinetic Monte Carlo (KMC), and an example of their application to radiation damage production and accumulation in metals. It is important to note at the outset that the primary objective of atomistic computer simulation should be obtaining physical insight into atomic-level processes. Classical molecular dynamics is a powerful method for obtaining insight about the dynamics of physical processes that occur on relatively short time scales. Current computational capability allows treatment of atomic systems containing as many as 10{sup 9} atoms for times on the order of 100 ns (10{sup -7}s). The main limitation of classical MD simulation is the relatively short times accessible. Kinetic Monte Carlo provides the ability to reach macroscopic times by modeling diffusional …
Date: October 10, 2000
Creator: Wirth, B. D.; Caturla, M. J. & Diaz de la Rubia, T.
System: The UNT Digital Library
[Draft of the NCAMSC Final Financial Report] (open access)

[Draft of the NCAMSC Final Financial Report]

Draft of the financial report from the National Center for Art Museum/School Collaborations funding for the North Texas Institute for Educators on the Visual Arts.
Date: May 10, 2000
Creator: unknown
System: The UNT Digital Library
Population Characteristics and Seasonal Movement Patterns of the Rattlesnake Hills Elk Herd - Status Report 2000 (open access)

Population Characteristics and Seasonal Movement Patterns of the Rattlesnake Hills Elk Herd - Status Report 2000

Population characteristics of the Rattlesnake Hills elk herd indicate reduced herd growth rates from the 1980s compared to the 1990s (McCorquodale 1988; Eberhardt 1996). However, the population continued to grow approximately 25% annually through the 1990s, reaching a high of 838 animals in summer 1999. Calf recruitment rates appear to be cyclic and are likely related to reduced calf survival during the first weeks of life; however, late-term abortions may also have occurred. The cause(s) could be predator-related and/or a function of shifts in nutritional condition (age-class distributions, assuming older-age cows are less likely to recruit calves, major climate shifts) or changes in the human-related disturbances during gestation, and/or calf rearing periods. In fall 1999 and spring 2000, the population was reduced from 838 individuals to 660 individuals. The primary controlling factors were modified hunting seasons on private and state lands and the large-scale roundup conducted in spring 2000. Continued removal of animals (particularly females) within the population will be pivotal to maintain the population at a level that minimizes land damage complaints, animal-vehicle collisions, use of central Hanford areas, and deterioration of natural resources.
Date: October 10, 2000
Creator: Tiller, B. L.; Zufelt, R. K.; Turner, S.; Cadwell, L. L.; Bender, L. & Turner, G. K.
System: The UNT Digital Library
The House Apportionment Formula in Theory and Practice (open access)

The House Apportionment Formula in Theory and Practice

This report has four major purposes: to summarize the constitutional and statutory requirements governing apportionment; to explain how the current apportionment formula works in theory and in practice; to summarize recent challenges to it on grounds of unfairness; and to explain the reasoning underlying the choice of the equal proportions method over its chief alternative, major fractions.
Date: October 10, 2000
Creator: Huckabee, David C.
System: The UNT Digital Library