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Sampling and Analysis Instruction for the 120-F-1 Glass Dump Site

Description: This sampling and analysis instruction has been prepared to clearly define the sampling and analysis activities to be performed to develop the basis for surveillance and maintenance of the 120-F-1 Glass Dumpsite. The purpose of this investigation is to augment historical information and obtain data to establish a technical basis for surveillance and maintenance at the site.
Date: March 1, 1998
Creator: Brown, T.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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{sup 170}Er: The search for multiphonon vibrations in a rotational nucleus

Description: To search for candidates for 2-phonon vibrations, {sup 170}Er was studied with the inelastic neutron scattering reaction. The level scheme was extended using {gamma}{gamma} coincidences and excitation functions. Spins were deduced from angular distribution measurements, and the Doppler-shift attenuation method (DSAM) was used to determine lifetimes.
Date: December 20, 1999
Creator: Garrett, P.; Warr, N.; Brown, T. B. & Martin, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Photoneutron production in electron beam stop for dual-axis radiographic hydrotest facility (DARHT)

Description: A beam stop design for an electron linear accelerator was analyzed from the perspective of photoneutron production and subsequent dose. Sophisticated nuclear data modeling codes were used to generate the photoneutron production cross sections and spectra that were then used in MCNP transport calculations. The resulting neutron dose exceeded limits for workers present in the experimental area while the accelerators are producing electron beam pulses. Therefore, the beam stop was redesigned to li… more
Date: March 1, 1998
Creator: Chadwick, M. B.; Brown, T. H. & Little, R. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Simplified approach for estimating large early release frequency

Description: The US Nuclear Regulatory Commission (NRC) Policy Statement related to Probabilistic Risk Analysis (PRA) encourages greater use of PRA techniques to improve safety decision-making and enhance regulatory efficiency. One activity in response to this policy statement is the use of PRA in support of decisions related to modifying a plant`s current licensing basis (CLB). Risk metrics such as core damage frequency (CDF) and Large Early Release Frequency (LERF) are recommended for use in making risk-i… more
Date: April 1, 1998
Creator: Pratt, W.T.; Mubayi, V.; Nourbakhsh, H.; Brown, T. & Gregory, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Foil fabrication for the ROMANO event. Revision 1

Description: The Vacuum Processes Lab (VPL), of LLNL's M.E. Dept. - Material Fabrication Division (MFD), conducted various vacuum related support activities for the ROMANO nuclear physics experiment. This report focuses on the foil fabrication activities carried out between July and November 1983 for the ROMANO event. Other vacuum related activities for ROMANO, such as outgassing tests of materials, are covered in separate documentation. VPL was asked to provide 270 coated Parylene foils for the ROMANO even… more
Date: June 13, 1984
Creator: Romo, J. G., Jr.; Weed, J. W.; Griggs, G. E.; Brown, T. G. & Tassano, P. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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DEALS magnet concept and its applcations to high density, high field tokamak systems

Description: The goal of the DEALS program is to develop a demountable TF magnet system concept that will reduce construction and life cycle costs, enhance the accessibility of components inside the coil system, and increase the chances for being able to use large high-field magnet systems in post TFTR reactor experiments. These experiments are projected to occur during the mid 1980's, with conceptual designs beginning in two or three years. A number of recent studies have highlighted the need for Tokamak f… more
Date: January 1, 1977
Creator: Hsieh, S.Y.; Powell, J.; Lehner, J.; Bezler, P.; Laverick, C.; Finkelman, M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Risk contribution from low power, shutdown, and other operational modes beyond full power

Description: During 1989 the Nuclear Regulatory Commission (NRC) initiated an extensive program to carefully examine the potential risks during low power and shutdown operations. Two plants, Surry (a pressurized water reactor) and Grand Gulf (a boiling water reactor), were selected for study by Brookhaven National Laboratory and Sandia National Laboratories, respectively. The program objectives included assessing the risks of severe accidents initiated during plant operational states other than full power a… more
Date: January 1, 1995
Creator: Whitehead, D. W.; Brown, T. D.; Chu, T. L. & Pratt, W. T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Response of C3 and C4 plants to middle-Holocene climatic variation near the prairie-forest ecotone of Minnesota, U.S.A.

Description: Paleorecords of the middle Holocene (MH) from the North American midcontinent can offer insights into ecological responses to pervasive drought that may accompany future climatic warming. We analyzed MH sediments from West Olaf Lake (WOL) and Steel Lake (SL) in Minnesota to examine the effects of warm/dry climatic conditions on prairie-woodland ecosystems. Mineral composition and carbonate {delta}{sup 18}O were used to determine climatic variations, whereas pollen assemblages, charcoal {delta}{… more
Date: December 24, 2003
Creator: Nelson, D. M.; Hu, F. S.; Tian, J.; Stefanova, I. & Brown, T. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of novel activated carbon-based adsorbents for control of Mercury emissions from coal-fired power plants

Description: The overall objective of this study is to evaluate pertinent design and operational parameters that would enable successful application of adsorption-based technologies for the reduction of mercury emissions from coal-fired power plants. The first part of the study will evaluate the most suitable impregnate for its ability to enhance the adsorptive capacity of activated carbon for mercury vapor under various process conditions. The second part of the study will evaluate the rate of mercury upta… more
Date: January 1, 1998
Creator: Vidic, R.D.; Liu, W. & Brown, T. D., University of Pittsburgh
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Application of Bomb Radiocarbon Chronologies to Shortfin Mako (Isurus oxyrinchus)

Description: There is an ongoing disagreement regarding the aging of the shortfin mako due to a difference of interpretation in the periodic deposition of vertebral growth band pairs, especially for the larger size classes. Using analysis of length-month information, tagging data, and length-frequency analysis, concluded that two band pairs were formed in the vertebral centrum every year (biannual band-pair interpretation). Cailliet et al. (1983), however, presented growth parameters based on the common ass… more
Date: July 16, 2007
Creator: Ardizzone, D; Cailliet, G M; Natanson, L J; Andrews, A H; Kerr, L A & Brown, T A
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Glacial Refugium of Pinus pumila (Pall.) Regel in Northeastern Siberia

Description: One of the most glowing representatives of the Kolyma flora [1], ''Pinus pumila'' (Pall.) Regel (Japanese stone pine), is a typical shrub in larch forests of the northern Okhotsk region, basins of the Kolyma and Indigirka rivers, and high-shrub tundra of the Chukchi Peninsula. It also forms a pine belt in mountains above the forest boundary, which gives way to the grass-underbrush mountain tundra and bald mountains. In the southern Chukchi Peninsula, ''Pinus pumila'' along with ''Duschekia frut… more
Date: February 10, 2007
Creator: Shilo, N A; Lozhkin, A V; Anderson, P M; Brown, T A; Pakhomov, A Y & Solomatkina, T B
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Ion-Source Modeling and Improved Performance of the CAMS High-Intensity Cs-Sputter Ion Source

Description: The interior of the high-intensity Cs-sputter source used in routine operations at the Center for Accelerator Mass Spectrometry (CAMS) has been computer modeled using the program NEDLab, with the aim of improving negative ion output. Space charge effects on ion trajectories within the source were modeled through a successive iteration process involving the calculation of ion trajectories through Poisson-equation-determined electric fields, followed by calculation of modified electric fields inc… more
Date: October 22, 1999
Creator: Brown, T. A.; Roberts, M. L. & Southon, J. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Bayesian methods for the combination of core sampling data with historical models for tank characterization

Description: A wide variety of information is available on the contents of the nuclear waste tanks at the Hanford site. This report describes an attempt to combine several sources of information using a Bayesian statistical approach. This methodology allows the combination of multiple disparate information sources. After each source of information is summarized in terms of a probability distribution function (pdf), Bayes` theorem is applied to combine them. This approach has been applied to characterizing t… more
Date: July 1, 1995
Creator: York, J. C.; Remund, K. M.; Chen, G.; Simpson, B. C. & Brown, T. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Market assessment and technical feasibility study of PFBC ash use

Description: The overall objectives of this study are to determine the market potential and the technical feasibility of using PFBC ash in high volume ash use applications. The information will be of direct use to the utility industry in assessing the economics of PFBC power generation in light of ash disposal avoidance through ash marketing. In addition, the research is expected to result in the generation of generic data on the use of PFBC ash that could lead to novel processing options and procedures. Th… more
Date: October 1, 1994
Creator: Smith, V. E.; Bland, A. E.; Brown, T. H.; Georgiou, D. N. & Wheeldon, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Collectivity of the ''Three-Phonon'' Region in {sup 100}Ru

Description: We have studied the quadrupole degree of freedom in a typical vibrational nucleus, {sup 100}Ru. From inelastic neutron scattering at the Van de Graaff accelerator of the University of Kentucky, lifetimes of states in {sup 100}Ru were determined. Absolute transition rates or limits thereon were extracted and compared to the theoretical description of this nucleus.
Date: December 21, 1999
Creator: Genilloud, L.; Brown, T.B.; Corminboeuf, G & Garrett, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Age validation of canary rockfish (Sebastes pinniger) using two independent otolith techniques: lead-radium and bomb radiocarbon dating.

Description: Canary rockfish (Sebastes pinniger) have long been an important part of recreational and commercial rockfish fishing from southeast Alaska to southern California, but localized stock abundances have declined considerably. Based on age estimates from otoliths and other structures, lifespan estimates vary from about 20 years to over 80 years. For the purpose of monitoring stocks, age composition is routinely estimated by counting growth zones in otoliths; however, age estimation procedures and li… more
Date: November 4, 2007
Creator: Andrews, A H; Kerr, L A; Cailliet, G M; Brown, T A; Lundstrom, C C & Stanley, R D
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Impact of a poloidal divertor in ignition tokamak design

Description: System design studies were performed to assess the effect of assuming a poloidal divertor instead of a limiter as a means of impurity control for ignition tokamak configurations. Results show that for the nominal Tokamak Fusion Core Experiment (TFCX) device with superconducting TF coils, a feasible poloidal divertor configuration can be obtained without increasing the major radius. In the TFCX nominal copper TF coil device, however, field limits at the PF coils are exceeded when the effects of … more
Date: January 1, 1985
Creator: Strickler, D. J.; Peng, Y. K. M.; Brown, T. G.; Dabiri, A. E.; Lee, V. D. & Miller, J. B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Evaluation of potential severe accidents during low power and shutdown operations at Grand Gulf, Unit 1. Analysis of core damage frequency from internal events for plant operational state 5 during a refueling outage. Internal events appendices K to M

Description: This report provides supporting documentation for various tasks associated with the performance of the probabilistic risk assessment for Plant Operational State 5 (approximately Cold Shutdown as defined by Grand Gulf Technical Specifications) during a refueling outage at Grand Gulf, Unit 1 as documented in Volume 2, Part 1 of NUREG/CR-6143. The report contains the following appendices: K - HEP Locator Files; L - Supporting Information for the Plant Damage State Analysis; M - Summary of Results … more
Date: July 1, 1994
Creator: Forester, J.; Yakle, J.; Walsh, B.; Darby, J.; Whitehead, D.; Staple, B. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Iodine-129 AMS for Earth Science, Biomedical, and National Security Applications

Description: This Laboratory Directed Research and Development project created the capability to analyze the radionuclide iodine-129 ({sup 129}I) by accelerator mass spectrometry (AMS) in the CAMS facility at LLNL, and enhanced our scientific foundation for its application through development of sample preparation technology required for environmental, biomedical, and national security applications. The project greatly improved our environmental iodine extraction and concentration methodology, and developed… more
Date: February 20, 2007
Creator: Nimz, G. J.; Brown, T. A.; Tumey, S. J.; Marchetti, A. A. & Vu, A. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Actinide Measurements by Accelerator Mass Spectrometry at Lawrence Livermore National Laboratory

Description: We report on the development of an accelerator mass spectrometry (AMS) system for the measurement of actinides at Lawrence Livermore National Laboratory. This AMS system is centered on a recently completed heavy isotope beam line that was designed particularly for high sensitivity, robust, high-throughput measurements of actinide concentrations and isotopic ratios. A fast isotope switching capability has been incorporated in the system, allowing flexibility in isotope selection and for the quas… more
Date: September 25, 2003
Creator: Brown, T A; Marchetti, A A; Martinelli, R E; Cox, C C; Knezovich, J P & Hamilton, T F
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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DEVELOPMENTS IN THE MEASUREMENT OF ACTINIDES AND129I AT LLNL BY ACCELERATOR MASS SPECTROMETRY

Description: The application of ultra-sensitive heavy isotope measurements continues to expand in a variety of fields relevant to the management of nuclear materials, including nuclear isotope forensics and radiobioassay. We have developed a heavy isotope accelerator mass spectrometry (AMS) system at Lawrence Livermore National Laboratory's (LLNL) Center for Accelerator Mass Spectrometry (CAMS). The system was designed particularly for the measurement of actinide concentrations and isotopic ratios, but also… more
Date: January 13, 2005
Creator: Brown, T A; Marchetti, A A; Weyhenmeyer, C E; Knezovich, J P; Hamilton, T F & Nimz, G J
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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