National Library of Energy BETA

Sample records for age age units

  1. AGING GAUGE

    DOE Patents [OSTI]

    Betts, Robert E.; Crawford, John F.

    1989-04-04

    An aging gauge comprising a container having a fixed or a variable sized t opening with a cap which can be opened to control the sublimation rate of a thermally sublimational material contained within the container. In use, the aging gauge is stored with an item to determine total heat the item is subjected to and also the maximum temperature to which the item has been exposed. The aging gauge container contains a thermally sublimational material such as naphthalene or similar material which has a low sublimation rate over the temperature range from about 70.degree. F. to about 160.degree. F. The aging products determined by analyses of a like item aged along with the aging gauge for which the sublimation amount is determined is employed to establish a calibration curve for future aging evaluation. The aging gauge is provided with a means for determining the maximum temperature exposure (i.e., a thermally indicating material which gives an irreversible color change, Thermocolor pigment). Because of the relationship of doubling reaction rates for increases of 10.degree. C., equivalency of item used in accelerated aging evaluation can be obtained by referring to a calibration curve depicting storage temperature on the abscissa scale and multiplier on the ordinate scale.

  2. Aging gauge

    DOE Patents [OSTI]

    Betts, Robert E.; Crawford, John F.

    1989-01-01

    An aging gauge comprising a container having a fixed or a variable sized t opening with a cap which can be opened to control the sublimation rate of a thermally sublimational material contained within the container. In use, the aging gauge is stored with an item to determine total heat the item is subjected to and also the maximum temperature to which the item has been exposed. The aging gauge container contains a thermally sublimational material such as naphthalene or similar material which has a low sublimation rate over the temperature range from about 70.degree. F. to about 160.degree. F. The aging products determined by analyses of a like item aged along with the aging gauge for which the sublimation amount is determined is employed to establish a calibration curve for future aging evaluation. The aging gauge is provided with a means for determining the maximum temperature exposure (i.e., a thermally indicating material which gives an irreversible color change, Thermocolor pigment). Because of the relationship of doubling reaction rates for increases of 10.degree. C., equivalency of item used in accelerated aging evaluation can be obtained by referring to a calibration curve depicting storage temperature on the abscissa scale and multiplier on the ordinate scale.

  3. Accelerated Aging Studies

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Accelerated Aging Studies LA-UR -15-27339 This document is approved for public release; further dissemination unlimited Property (max) log (aging time) Property (failure) Property (time=0) Accelerated Aging Data Predicted Storage Aging Response log (predicted lifetime) Property (max) log (aging time) Property (failure) Property (time=0) Accelerated Aging Data Predicted Storage Aging Response log (predicted lifetime) Accelerated Aging Studies Factors such as temperature, pressure, or radiation

  4. Accelerated Aging Studies

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Accelerated Aging Studies LA-UR -15-27339 This document is approved for public release; further dissemination unlimited Property (max) log (aging time) Property (failure) Property ...

  5. Parylene C Aging Studies.

    SciTech Connect (OSTI)

    Achyuthan, Komandoor; Sawyer, Patricia Sue.; Mata, Guillermo Adrian; White II, Gregory Von; Bernstein, Robert

    2014-09-01

    Parylene C is used in a device because of its conformable deposition and other advantages. Techniques to study Parylene C aging were developed, and %22lessons learned%22 that could be utilized for future studies are the result of this initial study. Differential Scanning Calorimetry yielded temperature ranges for Parylene C aging as well as post-deposition treatment. Post-deposition techniques are suggested to improve Parylene C performance. Sample preparation was critical to aging regimen. Short-term (~40 days) aging experiments with free standing and ceramic-supported Parylene C films highlighted %22lessons learned%22 which stressed further investigations in order to refine sample preparation (film thickness, single sided uniform coating, machine versus laser cutting, annealing time, temperature) and testing issues (%22necking%22) for robust accelerated aging of Parylene C.

  6. Design Evolution Study - Aging Options

    SciTech Connect (OSTI)

    P. McDaniel

    2002-04-05

    The purpose of this study is to identify options and issues for aging commercial spent nuclear fuel received for disposal at the Yucca Mountain Mined Geologic Repository. Some early shipments of commercial spent nuclear fuel to the repository may be received with high-heat-output (younger) fuel assemblies that will need to be managed to meet thermal goals for emplacement. The capability to age as much as 40,000 metric tons of heavy metal of commercial spent nuclear he1 would provide more flexibility in the design to manage this younger fuel and to decouple waste receipt and waste emplacement. The following potential aging location options are evaluated: (1) Surface aging at four locations near the North Portal; (2) Subsurface aging in the permanent emplacement drifts; and (3) Subsurface aging in a new subsurface area. The following aging container options are evaluated: (1) Complete Waste Package; (2) Stainless Steel inner liner of the waste package; (3) Dual Purpose Canisters; (4) Multi-Purpose Canisters; and (5) New disposable canister for uncanistered commercial spent nuclear fuel. Each option is compared to a ''Base Case,'' which is the expected normal waste packaging process without aging. A Value Engineering approach is used to score each option against nine technical criteria and rank the options. Open issues with each of the options and suggested future actions are also presented. Costs for aging containers and aging locations are evaluated separately. Capital costs are developed for direct costs and distributable field costs. To the extent practical, unit costs are presented. Indirect costs, operating costs, and total system life cycle costs will be evaluated outside of this study. Three recommendations for aging commercial spent nuclear fuel--subsurface, surface, and combined surface and subsurface are presented for further review in the overall design re-evaluation effort. Options that were evaluated but not recommended are: subsurface aging in a new subsurface area (high cost); surface aging in the complete waste package (risk to the waste package and impact on the Waste Handling Facility); and aging in the stainless steel liner (impact on the waste package design and new high risk operations added to the waste packaging process). The selection of a design basis for aging will be made in conjunction with the other design re-evaluation studies.

  7. Cancer and Aging

    SciTech Connect (OSTI)

    Campisi, Julie

    2015-05-06

    Berkeley Lab biochemist Judy Campisi discusses her work on understanding the molecular and cellular basis of aging and the control of cellular senescence and its role in tumor suppression.

  8. Aging and the geochemical environment

    SciTech Connect (OSTI)

    Not Available

    1981-01-01

    This report describes and assesses the aging process and related environmental aspects that may provide useful insights toward postponing some of the inevitable effects of aging. Although the Panel on Aging and the Geochemical Environment is convinced that the geochemical environment is associated with aging, it of course recognizes that other factors may also be significant or, perhaps, more important. Accordingly, the report is intended to enhance the awareness of biomedical and geochemical research scientists, decision makers in related areas, and the lay public interested in an understanding of the relation of the geochemical environment to senescence.

  9. Rock of Ages | Open Energy Information

    Open Energy Info (EERE)

    of Ages Jump to: navigation, search Name Rock of Ages Facility Rock of Ages Sector Wind energy Facility Type Small Scale Wind Facility Status In Service Owner Rock of Ages Energy...

  10. Transportation, Aging and Disposal Canister System Performance...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Transportation, Aging and Disposal Canister System Performance Specification: Revision 1 Transportation, Aging and Disposal Canister System Performance Specification: Revision 1 ...

  11. AGING SYSTEM DESIGN DEVELOPMENT STRATEGY

    SciTech Connect (OSTI)

    J. Beesley

    2005-02-07

    This plan provides an overview, work to date, and the path forward for the design development strategy of the Aging cask for aging commercial spent nuclear fuel (CSNF) at the Yucca Mountain Project (YMP) repository site. Waste for subsurface emplacement at the repository includes US Department of Energy (DOE) high-level radioactive waste (HLW), DOE SNF, commercial fuel in dual-purpose canisters (DPCs), uncanistered bare fuel, naval fuel, and other waste types. Table 1-1 lists the types of radioactive materials that may be aged at YMP, and those materials that will not be placed in an aging cask or module. This plan presents the strategy for design development of the Aging system. The Aging system will not handle naval fuel, DOE HLW, MCOs, or DOE SNF since those materials will be delivered to the repository in a state and sequence that allows them to be placed into waste packages for emplacement. Some CSNF from nuclear reactors, especially CSNF that is thermally too hot for emplacement underground, will need to be aged at the repository.

  12. AGING FACILITY CRITICALITY SAFETY CALCULATIONS

    SciTech Connect (OSTI)

    C.E. Sanders

    2004-09-10

    The purpose of this design calculation is to revise and update the previous criticality calculation for the Aging Facility (documented in BSC 2004a). This design calculation will also demonstrate and ensure that the storage and aging operations to be performed in the Aging Facility meet the criticality safety design criteria in the ''Project Design Criteria Document'' (Doraswamy 2004, Section 4.9.2.2), and the functional nuclear criticality safety requirement described in the ''SNF Aging System Description Document'' (BSC [Bechtel SAIC Company] 2004f, p. 3-12). The scope of this design calculation covers the systems and processes for aging commercial spent nuclear fuel (SNF) and staging Department of Energy (DOE) SNF/High-Level Waste (HLW) prior to its placement in the final waste package (WP) (BSC 2004f, p. 1-1). Aging commercial SNF is a thermal management strategy, while staging DOE SNF/HLW will make loading of WPs more efficient (note that aging DOE SNF/HLW is not needed since these wastes are not expected to exceed the thermal limits form emplacement) (BSC 2004f, p. 1-2). The description of the changes in this revised document is as follows: (1) Include DOE SNF/HLW in addition to commercial SNF per the current ''SNF Aging System Description Document'' (BSC 2004f). (2) Update the evaluation of Category 1 and 2 event sequences for the Aging Facility as identified in the ''Categorization of Event Sequences for License Application'' (BSC 2004c, Section 7). (3) Further evaluate the design and criticality controls required for a storage/aging cask, referred to as MGR Site-specific Cask (MSC), to accommodate commercial fuel outside the content specification in the Certificate of Compliance for the existing NRC-certified storage casks. In addition, evaluate the design required for the MSC that will accommodate DOE SNF/HLW. This design calculation will achieve the objective of providing the criticality safety results to support the preliminary design of the Aging Facility. As the ongoing design evolution remains fluid, the results from this design calculation should be evaluated for applicability to any new or modified design. Consequently, the results presented in this document are limited to the current design. The information contained in this document was developed by Environmental and Nuclear Engineering and is intended for the use of Design and Engineering in its work regarding the various criticality related activities performed in the Aging Facility. Yucca Mountain Project personnel from Environmental and Nuclear Engineering should be consulted before the use of the information for purposes other than those stated herein or use by individuals other than authorized personnel in Design and Engineering.

  13. Non-uniform Aging on Super Duty Diesel Truck Aged Urea Cu/Zeolite...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Aging on Super Duty Diesel Truck Aged Urea CuZeolite SCR Catalysts Non-uniform Aging on Super Duty Diesel Truck Aged Urea CuZeolite SCR Catalysts CuZeolite SCR catalysts aged ...

  14. Cell Senescence: Aging and Cancer

    ScienceCinema (OSTI)

    Campisi, Judith

    2013-05-29

    Scientists have identified a molecular cause behind the ravages of old age and in doing so have also shown how a natural process for fighting cancer in younger persons can actually promote cancer in older individuals.

  15. The age of the universe

    SciTech Connect (OSTI)

    Schramm, D.N.

    1996-10-01

    An overview of the current controversy on the age of the universe is presented. It is shown that the age of the oldest star, globular clusters, yields an age estimate of approximately 14 {+-} 2 {+-} 2 Gyr (where the first {+-} is statistical and the second systematic, and the two should {ital not} be added in quadrature), with a firm lower bound of {ge} 10 Gyr. It is shown how radioactive dating, nucleocosmochronology, also yields a firm lower bound of {approx_gt} 10 Gyr. The currently favored values for the Hubble constant, when converted to ages using a cosmological model with zero cosmological constant, are shown {ital not} to be in conflict with statistical and systematic uncertainties at the present time when one takes both into account, even for critical density universes. 25 refs. , 3 figs., 1 tab.

  16. Mechanical Testing of TR-55 Rubber Thermally Aged Under Tensile...

    Office of Scientific and Technical Information (OSTI)

    Country of Publication: United States Language: English Subject: 36 MATERIALS SCIENCE; AGING; ELONGATION; HEATING; RUBBERS; STIMULI; STRAINS; TESTING; ULTIMATE STRENGTH Word Cloud ...

  17. The Sandia MEMS Passive Shock Sensor : dormancy and aging. (Technical...

    Office of Scientific and Technical Information (OSTI)

    Sponsoring Org: USDOE Country of Publication: United States Language: English Subject: 47 OTHER INSTRUMENTATION; AGING; SENSORS; SHOCK WAVES; PERFORMANCE TESTING; MICROELECTRONIC ...

  18. Understanding aging in pentaerythritol tetranitrate

    SciTech Connect (OSTI)

    Brown, Geoffrey W; Sandstrom, Mary M; Giambra, Anna M; Archuleta, Jose G; Monroe, Deidre C

    2009-01-01

    Pentaerythritol Tetranitrate (PETN) powder is commonly used in detonators because of its sensitivity and explosive power. PETN detonation is largely determined by the average PETN particle size. This is an issue for aging and storage of weapons because PETN has a relatively high vapor pressure and its average particle size changes due to thermal energy input from the environment. PETN aging is a well known problem although the mechanism is not well understood. It is important to understand PETN aging so that predictive models can be constructed that will benefit stockpile surveillance and lifetime extension programs. PETN particles are known to coarsen over time at relatively low temperatures. Particle coarsening requires mass redistribution since decomposition causes powders to become finer as PETN mass is lost. Two possible mechanisms for mass redistribution are vapor phase transfer via sublimation-redeposition and solid-state mass transfer through surface diffusion. In this work we have examined PETN powders us ing permeability, atomic force microscopy (AFM), and optical microscopy based particle analysis. The results of these measurements lead us to a suggested coarsening mechanism that we reproduce with rudimentary simulations. The physical mechanisms used in the simulations are then used to create an empirical model of the coarsening that may be used to make predictions of PETN aging. In the future we will be measuring the vapor pressures and other physical properties of our powders to be able to make predictions using simulations.

  19. Aging and the geochemical environment

    SciTech Connect (OSTI)

    Not Available

    1981-01-01

    The report describes and assesses the aging process and related environmental aspects. Specific geographic areas of increased and decreased longevity were identified and geochemically characterized in terms of surface rocks, drinking water quality, soils, and abnormal absorption of trace elements by plants. Environmental factors that may be related to increased longevity are discussed. 11 references, 32 figures, 8 tables. (ACR)

  20. AGE UFMG Incubator | Open Energy Information

    Open Energy Info (EERE)

    search Name: AGE-UFMG Incubator Place: Brazil Sector: Services Product: General Financial & Legal Services ( Academic Research foundation ) References: AGE-UFMG...

  1. Asian Age Enterprise Ltd | Open Energy Information

    Open Energy Info (EERE)

    Ltd Jump to: navigation, search Name: Asian Age Enterprise Ltd Place: Dhaka, Bangladesh Zip: 1000 Product: Bangladeshi private project developer. References: Asian Age...

  2. Insights gained from aging research

    SciTech Connect (OSTI)

    Blahnik, D.E.; Casada, D.A.; Edson, J.L.; Fineman, D.L.; Gunther, W.E.; Haynes, H.D.; Hoopingarner, K.R.; Jacobus, M.J.; Jarrell, D.B.; Kryter, R.C.; Magelby, H.L.; Murphy, G.A.; Subudhi, M.M.

    1992-03-01

    The US NRC Office of Nuclear Regulatory Research has implemented hardware-oriented engineering research programs to identify and resolve technical issues related to the aging of systems, structures, and components (SSCs) in operating nuclear power plants. This report provides a summary of those research results which have been compiled and published in NUREGS and related technical reports. The systems, components and structures that have been studied are organized by alphabetical order. The research results summary on the SSCs is followed by an assessment guide to emphasize inspection techniques which may be useful for detecting aging degradation in nuclear power plants. This report will be updated periodically to reflect new research results on these or other SSCs.

  3. Transportation, Aging and Disposal Canister System Performance

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Specification: Revision 1 | Department of Energy Transportation, Aging and Disposal Canister System Performance Specification: Revision 1 Transportation, Aging and Disposal Canister System Performance Specification: Revision 1 This document provides specifications for selected system components of the Transportation, Aging and Disposal (TAD) canister-based system. PDF icon Transportation, Aging and Disposal Canister System Performance Specification: Revision 1 More Documents &

  4. Aging of Pentaerythritol Tetranitrate (PETN)

    SciTech Connect (OSTI)

    Foltz, M F

    2009-04-22

    Pentaerythritol tetranitrate (PETN) is a relatively sensitive explosive used in many electroexplosive devices as well as in medicine. Of primary interest to LLNL is its use in items such as exploding bridgewire (EBW) detonators and exploding bridge foil initiators (EFI). In these devices the crystalline powder is pressed into a granular, low-density compact that can be initiated by an exploding wire or foil. The long-term stability of this pressed compact is of interest to weapon stockpile lifetime prediction studies. Key points about potential aging mechanisms can be summarized as follows: (1) There are a number of factors that can contribute to PETN instability. These include particle size, polymorphic phase transitions, crystal structure, impurities, moisture, occlusions, chemical incompatibility and biological (microorganism) action. of these factors the most important for long-term aging of high surface area powders used in detonators appears to be that of particle size growth. (2) There is a great deal of literature on the thermal degradation kinetics of PETN, unfortunately much of it with little bearing on ambient temperature aging during long-term storage. PETN is very stable with respect to thermal decomposition. Low-temperature thermal studies have not revealed evidence of chemical degradation products in archived PETN. Data extrapolated to 30 C predicts a half-life of 12 million years. (3) Moisture seems to lower the activation energy for and accelerate the decomposition of PETN. (4) External drivers affecting stability include temperature, moisture, radiation fields, and stress, while internal drivers include residual solvents, and impurities. Temperature affects kinetic processes of crystal growth such as adsorption, desorption, and diffusion rates of molecules on the surface of PETN crystals. A low-level radiation field may induce unexpected changes in the chemical makeup of PETN and its homologue impurities. Stress at high pressure points caused by crystalline surface irregularities may cause a decrease in surface area over time due to smoothing of contact points and sintering. PETN has been found to contain a number of impurities, including homologues, pentaerythryl ethers with a mixture of hydroxyl and nitrate functional groups, and organic salts, that can alter its physical and chemical properties. (5) The processes of sublimation/recrystallization and surface diffusion are important processes that can cause changes in PETN crystal morphology, particle size distribution and specific surface area. Sublimation feeds a process called Ostwald ripening, which involves the spontaneous growth of larger crystals from those of smaller size. This process proceeds with age regardless of storage conditions unless the crystals are treated to retard growth. The coarsening mechanisms include Ostwald ripening, 'sintering', and surface diffusion. The latter has not been experimentally observed, but a molecular modeling approach has attempted to investigate this phenomenon theoretically. (6) Threshold test fire, particle size distribution, specific surface area, thermal analysis, chemical analysis, powder compact specific surface area and density are approaches that have been used in the attempt to assess changes attributable to aging of PETN, with varying results. The biggest problem lies in the aging mechanism itself, which likely influences small changes in morphology, both internal and external, and particle size distribution changes on a scale too small to reliably monitor. Other aspects, such as subtle changes in density profiles within pressed powder compacts, may be beyond the capability of current technology to assess. Crystal growth significant enough to affect the PETN particle size distribution is expected to impact detonator performance. (7) Factors relevant to stabilizing particle size growth include crystal morphology, powder surface area and particle size distribution; crystal density and internal defects; and powder compact density and density gradients.

  5. SNF AGING SYSTEM DESCRIPTION DOCUMENT

    SciTech Connect (OSTI)

    L.L. Swanson

    2005-04-06

    The purpose of this system description document (SDD) is to establish requirements that drive the design of the spent nuclear fuel (SNF) aging system and associated bases, which will allow the design effort to proceed. This SDD will be revised at strategic points as the design matures. This SDD identifies the requirements and describes the system design, as it currently exists, with emphasis on attributes of the design provided to meet the requirements. This SDD is an engineering tool for design control; accordingly, the primary audience and users are design engineers. This SDD is part of an iterative design process. It leads the design process with regard to the flow down of upper tier requirements onto the system. Knowledge of these requirements is essential in performing the design process. The SDD follows the design with regard to the description of the system. The description provided in the SDD reflects the current results of the design process. Throughout this SDD, the term aging cask applies to vertical site-specific casks and to horizontal aging modules. The term overpack is a vertical site-specific cask that contains a dual-purpose canister (DPC) or a disposable canister. Functional and operational requirements applicable to this system were obtained from ''Project Functional and Operational Requirements'' (F&OR) (Curry 2004 [DIRS 170557]). Other requirements that support the design process were taken from documents such as ''Project Design Criteria Document'' (PDC) (BSC 2004 [DES 171599]), ''Site Fire Hazards Analyses'' (BSC 2005 [DIRS 172174]), and ''Nuclear Safety Design Bases for License Application'' (BSC 2005 [DIRS 171512]). The documents address requirements in the ''Project Requirements Document'' (PRD) (Canori and Leitner 2003 [DIRS 166275]). This SDD includes several appendices. Appendix A is a Glossary; Appendix B is a list of key system charts, diagrams, drawings, lists and additional supporting information; and Appendix C is a list of procedures that will be used to operate the system.

  6. The New ICE Age | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    for the heavy truck market PDF icon deer12gruden.pdf More Documents & Publications The New ICE Age The New ICE Age Roadmapping Engine Technology for Post-2020 Heavy Duty ...

  7. Aging induced property changes in metal tritides

    SciTech Connect (OSTI)

    Schober, T.

    1988-09-01

    Recent aging studies performed on dilute and concentrated metal tritides are reviewed. Also, new results concerning property changes in metal tritides as a function of aging time are included. The authors mainly report on TEM studies of aged tritides, the swelling behavior, hardness measurements, selected mechanical properties, acoustic emission and tritium diffusion experiments. Models of the microstructure of aged tritides are also reported. Density measurements on tritides are discussed.

  8. Characterization of Field-Aged Exhaust Gas Recirculation Cooler...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Field-Aged Exhaust Gas Recirculation Cooler Deposits Characterization of Field-Aged Exhaust Gas Recirculation Cooler Deposits Characterized field-aged exhaust gas recirculation ...

  9. Computational Age Dating of Special Nuclear Materials

    SciTech Connect (OSTI)

    2012-06-30

    This slide-show presented an overview of the Constrained Progressive Reversal (CPR) method for computing decays, age dating, and spoof detecting. The CPR method is: Capable of temporal profiling a SNM sample; Precise (compared with known decay code, such a ORIGEN); Easy (for computer implementation and analysis).  We have illustrated with real SNM data using CPR for age dating and spoof detection. If SNM is pure, may use CPR to derive its age. If SNM is mixed, CPR will indicate that it is mixed or spoofed.

  10. Aging study of boiling water reactor high pressure injection systems

    SciTech Connect (OSTI)

    Conley, D.A.; Edson, J.L.; Fineman, C.F.

    1995-03-01

    The purpose of high pressure injection systems is to maintain an adequate coolant level in reactor pressure vessels, so that the fuel cladding temperature does not exceed 1,200{degrees}C (2,200{degrees}F), and to permit plant shutdown during a variety of design basis loss-of-coolant accidents. This report presents the results of a study on aging performed for high pressure injection systems of boiling water reactor plants in the United States. The purpose of the study was to identify and evaluate the effects of aging and the effectiveness of testing and maintenance in detecting and mitigating aging degradation. Guidelines from the United States Nuclear Regulatory Commission`s Nuclear Plant Aging Research Program were used in performing the aging study. Review and analysis of the failures reported in databases such as Nuclear Power Experience, Licensee Event Reports, and the Nuclear Plant Reliability Data System, along with plant-specific maintenance records databases, are included in this report to provide the information required to identify aging stressors, failure modes, and failure causes. Several probabilistic risk assessments were reviewed to identify risk-significant components in high pressure injection systems. Testing, maintenance, specific safety issues, and codes and standards are also discussed.

  11. Evidence of aging effects on certain safety-related components

    SciTech Connect (OSTI)

    Magleby, H.L.; Atwood, C.L.; MacDonald, P.E.; Edson, J.L.; Bramwell, D.L.

    1996-01-01

    In response to interest shown by the Nuclear Energy Agency (NEA), Principal Working Group I (PWG- 1) of the Committee on the Safety of Nuclear Installations (CSNI) conducted a generic study on the effects of aging of active components in nuclear power plants. (This focus on active components is consistent with PWG-l`s mandate; passive components are primarily within the mandate of PWG-3.) Representatives from France, Sweden, Finland, Japan, the United States, and the United Kingdom participated in the study by submitting reports documenting aging studies performed in their countries. This report consists of summaries of those reports, along with a comparison of the various statistical analysis methods used in the studies. The studies indicate that with some exceptions, active components generally do not present a significant aging problem in nuclear power plants. Design criteria and effective preventative maintenance programs, including timely replacement of components, are effective in mitigating potential aging problems. However, aging studies (such as qualitative and statistical analyses of failure modes and maintenance data) are an important part of efforts to identify and solve potential aging problems. Solving these problems typically includes such strategies as replacing suspect components with improved components, and implementing improved maintenance programs.

  12. Cast Stainless Steel Aging Research Plan

    Broader source: Energy.gov [DOE]

    This work plan proposes to build a systematic knowledge base for the thermal aging behavior of cast stainless steels (CASSs) within a limited time of five years. The final output of execution of...

  13. Documenting stone age cleverness by tool development

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Documenting stone age cleverness by tool development Documenting stone age cleverness by tool development Ancient stone tools show the pace of remarkable technological enhancements over time. March 7, 2013 Ancient stone tools showing the pace of remarkable technological enhancements over time (1.75 to 0.85 million years ago). Credit, Los Alamos National Laboratory. Ancient stone tools showing the pace of remarkable technological enhancements over time (1.75 to 0.85 million years ago). Credit,

  14. Maximum Entry and Mandatory Separation Ages for Certain Security Employees

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2001-10-11

    The policy establishes the DOE policy on maximum entry and mandatory separation ages for primary or secondary positions covered under special statutory retirement provisions and for those employees whose primary duties are the protection of officials of the United States against threats to personal safety or the investigation, apprehension, and detention of individuals suspected or convicted of offenses against the criminal laws of the United States. Admin Chg 1, dated 12-1-11, supersedes DOE P 310.1.

  15. Bayes Method Plant Aging Risk Analysis

    Energy Science and Technology Software Center (OSTI)

    1992-03-13

    DORIAN is an integrated package for performing Bayesian aging analysis of reliability data; e.g. for identifying trends in component failure rates and/or outage durations as a function of time. The user must specify several alternatives hypothesized aging models (i.e. possible trends) along with prior probabilities indicating the subjective probability that each trend is actually the correct one. DORIAN then uses component failure and/or repair data over time to update these prior probabilities and develop amore » posterior probability for each aging model, representing the probability that each model is the correct one in light of the observed data rather than a priori. Mean, median, and 5th and 95th percentile trends are also compiled from the posterior probabilities.« less

  16. Ending Aging in Super Glassy Polymer Membranes

    SciTech Connect (OSTI)

    Lau, CH; Nguyen, PT; Hill, MR; Thornton, AW; Konstas, K; Doherty, CM; Mulder, RJ; Bourgeois, L; Liu, ACY; Sprouster, DJ; Sullivan, JP; Bastow, TJ; Hill, AJ; Gin, DL; Noble, RD

    2014-04-16

    Aging in super glassy polymers such as poly(trimethylsilylpropyne) (PTMSP), poly(4-methyl-2-pentyne) (PMP), and polymers with intrinsic microporosity (PIM-1) reduces gas permeabilities and limits their application as gas-separation membranes. While super glassy polymers are initially very porous, and ultra-permeable, they quickly pack into a denser phase becoming less porous and permeable. This age-old problem has been solved by adding an ultraporous additive that maintains the low density, porous, initial stage of super glassy polymers through absorbing a portion of the polymer chains within its pores thereby holding the chains in their open position. This result is the first time that aging in super glassy polymers is inhibited whilst maintaining enhanced CO2 permeability for one year and improving CO2/N-2 selectivity. This approach could allow super glassy polymers to be revisited for commercial application in gas separations.

  17. Tritium Aging Effects in Palladium on Kieselguhr

    SciTech Connect (OSTI)

    Shanahan, K.L.; Holder, J.S.; Wermer, J.R.

    1998-10-01

    50 weight % Pd on kieselguhr (Pd/k) is used in hydrogen isotope separation processes at the Savannah River Site. Long term aging studies on this material were undertaken in June, 1992. P-c-T data showing the aging effect of tritium loading for long periods will be presented and discussed covering from June, 1992 to March, 1997. Lowering of plateau pressures and increasing indications of in homogeneities have been observed in both tritium and deuterium absorption isotherms at 0 C, and desorption isotherms at 80 and 120 C.

  18. Aging assessment of reactor instrumentation and protection system components. Aging-related operating experiences

    SciTech Connect (OSTI)

    Gehl, A.C.; Hagen, E.W.

    1992-07-01

    A study of the aging-related operating experiences throughout a five-year period (1984--1988) of six generic instrumentation modules (indicators, sensors, controllers, transmitters, annunciators, and recorders) was performed as a part of the Nuclear Plant Aging Research Program. The effects of aging from operational and environmental stressors were characterized from results depicted in Licensee Event Reports (LERs). The data are graphically displayed as frequency of events per plant year for operating plant ages from 1 to 28 years to determine aging-related failure trend patterns. Three main conclusions were drawn from this study: (1) Instrumentation and control (I&C) modules make a modest contribution to safety-significant events: 17% of LERs issued during 1984--1988 dealt with malfunctions of the six I&C modules studied, and 28% of the LERs dealing with these I&C module malfunctions were aging related (other studies show a range 25--50%); (2) Of the six modules studied, indicators, sensors, and controllers account for the bulk (83%) of aging-related failures; and (3) Infant mortality appears to be the dominant aging-related failure mode for most I&C module categories (with the exception of annunciators and recorders, which appear to fail randomly).

  19. The Sandia MEMS Passive Shock Sensor : dormancy and aging. (Technical

    Office of Scientific and Technical Information (OSTI)

    Report) | SciTech Connect The Sandia MEMS Passive Shock Sensor : dormancy and aging. Citation Details In-Document Search Title: The Sandia MEMS Passive Shock Sensor : dormancy and aging. This report presents the results of an aging experiment that was established in FY09 and completed in FY10 for the Sandia MEMS Passive Shock Sensor. A total of 37 packages were aged at different temperatures and times, and were then tested after aging to determine functionality. Aging temperatures were

  20. The Next ICE Age | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    developments in diesel engines for light- and heavy-duty applications PDF icon deer12_ruth.pdf More Documents & Publications The Next ICE Age Cummins SuperTruck Program - Technology and System Level Demonstration of Highly Efficient and Clean, Diesel Powered Class 8 Trucks SuperTruck Program: Engine Project Review

  1. Mechanical Testing of TR-55 Rubber Thermally Aged Under Tensile...

    Office of Scientific and Technical Information (OSTI)

    Mechanical Testing of TR-55 Rubber Thermally Aged Under Tensile Strain Citation Details In-Document Search Title: Mechanical Testing of TR-55 Rubber Thermally Aged Under Tensile ...

  2. Tensile Testing of Aged TR-55 Silicone Rubber (Gamma Radiation...

    Office of Scientific and Technical Information (OSTI)

    Tensile Testing of Aged TR-55 Silicone Rubber (Gamma Radiation Under Tensile Strain): ... Title: Tensile Testing of Aged TR-55 Silicone Rubber (Gamma Radiation Under Tensile ...

  3. Diagnostic and Prognostic Analysis of Battery Performance & Aging...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Diagnostic and Prognostic Analysis of Battery Performance & Aging based on Kinetic and ... More Documents & Publications Diagnostic Testing and Analysis Toward Understanding Aging ...

  4. Space-Age Ceramics Get Their Toughest Test

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Space-Age Ceramics Get Their Toughest Test Print Advanced ceramic composites can withstand ... of the mechanical properties of these space-age materials at ultrahigh temperatures ...

  5. Aging and deaging effects in shape memory alloys (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Aging and deaging effects in shape memory alloys Citation Details In-Document Search Title: Aging and deaging effects in shape memory alloys Authors: Xue, Dezhen ; Zhou, Yumei ; ...

  6. Aging and deaging effects in shape memory alloys (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Aging and deaging effects in shape memory alloys Title: Aging and deaging effects in shape memory alloys Authors: Xue, Dezhen ; Zhou, Yumei ; Ding, Xiangdong ; Lookman, Turab ; ...

  7. Adapting Dry Cask Storage for Aging at a Geologic Repository

    SciTech Connect (OSTI)

    C. Sanders; D. Kimball

    2005-08-02

    A Spent Nuclear Fuel (SNF) Aging System is a crucial part of operations at the proposed Yucca Mountain repository in the United States. Incoming commercial SNF that does not meet thermal limits for emplacement will be aged on outdoor pads. U.S. Department of Energy SNF will also be managed using the Aging System. Proposed site-specific designs for the Aging System are closely based upon designs for existing dry cask storage (DCS) systems. This paper evaluates the applicability of existing DCS systems for use in the SNF Aging System at Yucca Mountain. The most important difference between existing DCS facilities and the Yucca Mountain facility is the required capacity. Existing DCS facilities typically have less than 50 casks. The current design for the aging pad at Yucca Mountain calls for a capacity of over 2,000 casks (20,000 MTHM) [1]. This unprecedented number of casks poses some unique problems. The response of DCS systems to off-normal and accident conditions needs to be re-evaluated for multiple storage casks. Dose calculations become more complicated, since doses from multiple or very long arrays of casks can dramatically increase the total boundary dose. For occupational doses, the geometry of the cask arrays and the order of loading casks must be carefully considered in order to meet ALARA goals during cask retrieval. Due to the large area of the aging pad, skyshine must also be included when calculating public and worker doses. The expected length of aging will also necessitate some design adjustments. Under 10 CFR 72.236, DCS systems are initially certified for a period of 20 years [2]. Although the Yucca Mountain facility is not intended to be a storage facility under 10 CFR 72, the operational life of the SNF Aging System is 50 years [1]. Any cask system selected for use in aging will have to be qualified to this design lifetime. These considerations are examined, and a summary is provided of the adaptations that must be made in order to use DCS technologies successfully at a geologic repository.

  8. Insights into accelerated aging of SSL luminaires

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Davis, J. Lynn; Lamvik, Michael; Bittle, James; Shepherd, Sarah; Yaga, Robert; Baldasaro, Nick; Solano, Eric; Bobashev, Georgiy

    2013-09-30

    Although solid-state lighting (SSL) products are often intended to have product lifetimes of 15 years or more, the rapid change in technology has created a need for accelerated life tests (ALTs) that can be performed in the span of several months. A critical element of interpreting results from any systems-level ALT is understanding of the impact of the test environment on each component. Because of its ubiquity in electronics, the use of temperature-humidity environments as potential ALTs for SSL luminaires was investigated. Results from testing of populations of three commercial 6” downlights in environments of 85oC and 85% relative humiditymore » (RH) and 75oC and 75% RH are reported. These test environments were found to accelerate lumen depreciation of the entire luminaire optical system, including LEDs, lenses, and reflectors. The effects of aging were found to depend strongly on both the optical materials that were used and the design of the luminaire; this shows that the lumen maintenance behavior of SSL luminaires must be addressed at the optical systems level. Temperature-Humidity ALTs can be a useful test in understand lumainaire depreciation provided that proper consideration is given to the different aging rates of various materials. Since the impact of the temperature-humidity environment varies among components of the optical system, uniform aging of all system components in a single test is difficult to achieve.« less

  9. Insights into accelerated aging of SSL luminaires

    SciTech Connect (OSTI)

    Davis, J. Lynn; Lamvik, Michael; Bittle, James; Shepherd, Sarah; Yaga, Robert; Baldasaro, Nick; Solano, Eric; Bobashev, Georgiy

    2013-09-30

    Although solid-state lighting (SSL) products are often intended to have product lifetimes of 15 years or more, the rapid change in technology has created a need for accelerated life tests (ALTs) that can be performed in the span of several months. A critical element of interpreting results from any systems-level ALT is understanding of the impact of the test environment on each component. Because of its ubiquity in electronics, the use of temperature-humidity environments as potential ALTs for SSL luminaires was investigated. Results from testing of populations of three commercial 6 downlights in environments of 85oC and 85% relative humidity (RH) and 75oC and 75% RH are reported. These test environments were found to accelerate lumen depreciation of the entire luminaire optical system, including LEDs, lenses, and reflectors. The effects of aging were found to depend strongly on both the optical materials that were used and the design of the luminaire; this shows that the lumen maintenance behavior of SSL luminaires must be addressed at the optical systems level. Temperature-Humidity ALTs can be a useful test in understand lumainaire depreciation provided that proper consideration is given to the different aging rates of various materials. Since the impact of the temperature-humidity environment varies among components of the optical system, uniform aging of all system components in a single test is difficult to achieve.

  10. COTNAINSETREFERENCE NO OF DOCUMENT BEING CONTINUED ~AGE OF

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    NO OF DOCUMENT BEING CONTINUED ~AGE OF CONINUTIO SHE PF, , '-C c NAME OF OFFEROR OR CONTRACTOR WASHAINGTON. 1 IVEP, PPOTFCIO SDO2LUYI, roLT ITEM NO SUPPLIES/SERVICES QUANTITY UNIT UNIT PRICE AMOUNT App-rl Usel fU))J ( P~~PA 14 CIYBI Pr-' T 1, Contract N umber I)E-AC27-08RVI 4800 Continuation Page, Modification 106 Pagye 3 of 4 Attachment DE-AC27-O8RVI 4800, MODIFICATION 106 Replacement Pages Section B, Page B-3, (2 pages total including this cover page) Tank Operations Contract Section B

  11. Helium Release Behavior of Aged Titanium Tritides

    SciTech Connect (OSTI)

    SHANAHAN, KIRKL.

    2004-07-27

    One sample of bulk Ti has been loaded with a 50 per cent / 50 per cent deuterium/tritium mixture and statically aged for 6.5 years. Thermal desorption of the sample shows an initial release of hydrogen isotopes followed by 3He release. Subsequent D2 loading/desorption was used to quantify the trapped tritium heel. The sample shows an excess hydrogen capacity as a second thermal desorption peak that partially disappears and shifts with annealing at 923-973K. The main hydrogen desorption peak also shifts to higher temperature, indicating a partial reversal of the tritium-decay induced damage by annealing.

  12. Deactivation of Accelerated Engine-Aged and Field-Aged SCR Catalysts and

    Broader source: Energy.gov (indexed) [DOE]

    the Role of the DOC | Department of Energy A technique for accelerated aging of SCR system (DOC -> SCR-> DPF) reveals two deactivation mechanisms and replicates field-aged effects PDF icon deer09_toops.pdf More Documents & Publications Impact of Biodiesel-Based Na on the Selective Catalytic Reduction (SCR) of NOx Using Cu-zeolite Impacts of Biodiesel on Emission Control Devices Vehicle Technologies Office: 2008-2009 Fuels Technologies R&D Progress Report

  13. Overview of Modeling and Simulations of Plutonium Aging

    SciTech Connect (OSTI)

    Schwartz, A J; Wolfer, W G

    2007-04-24

    Computer-aided materials research is now an integral part of science and technology. It becomes particularly valuable when comprehensive experimental investigations and materials testing are too costly, hazardous, or of excessive duration; then, theoretical and computational studies can supplement and enhance the information gained from limited experimental data. Such is the case for improving our fundamental understanding of the properties of aging plutonium in the nuclear weapons stockpile. The question of the effects of plutonium aging on the safety, security, and reliability of the nuclear weapons stockpile emerged after the United States closed its plutonium manufacturing facility in 1989 and decided to suspend any further underground testing of nuclear weapons in 1992. To address this, the Department of Energy's National Nuclear Security Administration (NNSA) initiated a research program to investigate plutonium aging, i.e., the changes with time of properties of Pu-Ga alloys employed in the nuclear weapons and to develop models describing these changes sufficiently reliable to forecast them for several decades. The November 26, 2006 press release by the NNSA summarizes the conclusions of the investigation, '...there appear to be no serious or sudden changes occurring, or expected to occur, in plutonium that would affect performance of pits beyond the well-understood, gradual degradation of plutonium materials'. Furthermore, 'These studies show that the degradation of plutonium in our nuclear weapons will not affect warhead reliability for decades', then NNSA Administrator Linton Brooks said. 'It is now clear that although plutonium aging contributes, other factors control the overall life expectancy of nuclear weapons systems'. The origin of plutonium aging is the natural decay of certain plutonium isotopes. Specifically, it is the process of alpha decay in which a plutonium atom spontaneously splits into a 5 MeV alpha particle and an 85keV uranium recoil. The alpha particle traverses the lattice, slowly loosing energy through electronic excitations, acquiring two electrons to become a helium atom, then finally coming to rest approximately 10 microns away with the generation of a few-hundred Frenkel pairs. The uranium recoil immediately displaces a couple-thousand Pu atoms from their original lattice sites. This process, which occurs at a rate of approximately 41 parts-per-million per year, is the source of potential property changes in aging plutonium. Plutonium aging encompasses many areas of research: radiation damage and radiation effects, diffusion of point defects, impurities and alloying elements, solid state phase transformations, dislocation dynamics and mechanical properties, equations of state under extreme pressures, as well as surface oxidation and corrosion. Theory, modeling, and computer simulations are involved to various degrees in many of these areas. The joint research program carried out at Lawrence Livermore National Laboratory and Los Alamos National Laboratory encompassed experimental measurements of numerous properties of newly fabricated reference alloys, archival material that have accumulated the effects of several decades of radioactive decay, and accelerated aging alloys in which the isotropic composition was adjusted to increase the rate of self-irradiation damage. In particular, the physical and chemical processes of nuclear materials degradation were to be studied individually and in great depth. Closely coupled to the experimental efforts are theory, modeling, and simulations. These efforts, validated by the experiments, aim to develop predictive models to evaluate the effects of age on the properties of plutonium. The need to obtain a scientific understanding of plutonium aging has revitalized fundamental research on actinides and plutonium in particular. For example, the experimental discovery of superconductivity in Pu-based compounds, the observation of helium bubbles in naturally aged material, and the measurement of phonon dispersion properties in gallium-stabilized delta plu

  14. Age Dating of Mixed SNM--Preliminary Investigations

    SciTech Connect (OSTI)

    Yuan, D., Guss, P. P., Yfantis, E., Klingensmith, A., Emer, D.

    2011-12-01

    Recently we investigated the nuclear forensics problem of age determination for mixed special nuclear material (SNM). Through limited computational mixing experiments and interactive age analysis, it was observed that age dating results are generally affected by the mixing of samples with different assays or even by small radioactive material contamination. The mixing and contamination can be detected through interactive age analysis, a function provided by the Decay Interaction, Visualization and Analysis (DIVA) software developed by NSTec. It is observed that for mixed SNM with two components, the age estimators typically fall into two distinct clusters on the time axis. This suggests that averaging or other simple statistical methods may not always be suitable for age dating SNM mixtures. Instead, an interactive age analysis would be more suitable for age determination of material components of such SNM mixtures. This work was supported by the National Center for Nuclear Security (NCNS).

  15. Energy age wind ltd Co KG | Open Energy Information

    Open Energy Info (EERE)

    48291 Sector: Wind energy Product: Energy-age-wind aims to develop small scale vertical-axis wind turbines. References: energy-age-wind ltd & Co. KG1 This article is a stub....

  16. Space-Age Ceramics Get Their Toughest Test

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Space-Age Ceramics Get Their Toughest Test Space-Age Ceramics Get Their Toughest Test Print Wednesday, 17 April 2013 07:23 Advanced ceramic composites can withstand the ultrahigh ...

  17. Space-Age Ceramics Get Their Toughest Test

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Space-Age Ceramics Get Their Toughest Test Space-Age Ceramics Get Their Toughest Test Print Tuesday, 11 December 2012 14:54 Advanced ceramic composites can withstand the ultrahigh ...

  18. Fact #614: March 15, 2010 Average Age of Household Vehicles

    Broader source: Energy.gov [DOE]

    The average age of household vehicles has increased from 6.6 years in 1977 to 9.2 years in 2009. Pickup trucks have the oldest average age in every year listed. Sport utility vehicles (SUVs), first...

  19. Enzyme Structure Provides Insights into Cancer and Aging

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Enzyme Structure Provides Insights into Cancer and Aging Enzyme Structure Provides Insights into Cancer and Aging Print Wednesday, 25 February 2009 00:00 XPD helicase is an enzyme...

  20. Sean; Tanner, Danelle Mary 47 OTHER INSTRUMENTATION; AGING; SENSORS...

    Office of Scientific and Technical Information (OSTI)

    an aging experiment that was established in FY09 and completed in FY10 for the Sandia MEMS Passive Shock Sensor. A total of 37 packages were aged at different temperatures and...

  1. Emerging nondestructive inspection methods for aging aircraft

    SciTech Connect (OSTI)

    Beattie, A; Dahlke, L; Gieske, J

    1994-01-01

    This report identifies and describes emerging nondestructive inspection (NDI) methods that can potentially be used to inspect commercial transport and commuter aircraft for structural damage. The nine categories of emerging NDI techniques are: acoustic emission, x-ray computed tomography, backscatter radiation, reverse geometry x-ray, advanced electromagnetics, including magnetooptic imaging and advanced eddy current techniques, coherent optics, advanced ultrasonics, advanced visual, and infrared thermography. The physical principles, generalized performance characteristics, and typical applications associated with each method are described. In addition, aircraft inspection applications are discussed along with the associated technical considerations. Finally, the status of each technique is presented, with a discussion on when it may be available for use in actual aircraft maintenance programs. It should be noted that this is a companion document to DOT/FAA/CT-91/5, Current Nondestructive Inspection Methods for Aging Aircraft.

  2. Passive absolute age and temperature history sensor

    DOE Patents [OSTI]

    Robinson, Alex; Vianco, Paul T.

    2015-11-10

    A passive sensor for historic age and temperature sensing, including a first member formed of a first material, the first material being either a metal or a semiconductor material and a second member formed of a second material, the second material being either a metal or a semiconductor material. A surface of the second member is in contact with a surface of the first member such that, over time, the second material of the second member diffuses into the first material of the first member. The rate of diffusion for the second material to diffuse into the first material depends on a temperature of the passive sensor. One of the electrical conductance, the electrical capacitance, the electrical inductance, the optical transmission, the optical reflectance, or the crystalline structure of the passive sensor depends on the amount of the second material that has diffused into the first member.

  3. Evaluation of aging degradation of structural components

    SciTech Connect (OSTI)

    Chopra, O.K.; Shack, W.J.

    1992-03-01

    Irradiation embrittlement of the neutron shield tank (NST) A212 Grade B steel from the Shippingport reactor, as well as thermal embrittlement of CF-8 cast stainless steel components from the Shippingport and KRB reactors, has been characterized. Increases in Charpy transition temperature (CTT), yield stress, and hardness of the NST material in the low-temperature low-flux environment are consistent with the test reactor data for irradiations at < 232{degrees}C. The shift in CTT is not as severe as that observed in surveillance samples from the High Flux Isotope Reactor (HFIR): however, it shows very good agreement with the results for HFIR A212-B steel irradiated in the Oak Ridge Research Reactor. The results indicate that fluence rate has not effect on radiation embrittlement at rates as low as 2 {times} 10{sup 8} n/cm{sup 2}{center dot}s at the low operating temperature of the Shippingport NST, i.e., 55{degrees}C. This suggest that radiation damage in Shippingport NST and HFIR surveillance samples may be different because of the neutron spectra and/or Cu and Ni content of the two materials. Cast stainless steel components show relatively modest decreases in fracture toughness and Charpy-impact properties and a small increase in tensile strength. Correlations for estimating mechanical properties of cast stainless steels predict accurate or slightly conservative values for Charpy-impact energy, tensile flow stress, fracture toughness J-R curve, and J{sub IC} of the materials. The kinetics of thermal embrittlement and degree of embrittlement at saturation, i.e., the minimum impact energy achieved after long-term aging, were established from materials that were aged further in the laboratory. The results were consistent with the estimates. The correlations successfully predict the mechanical properties of the Ringhals 2 reactor hot- and crossover-leg elbows (CF-8M steel) after service of {approx}15 y.

  4. Evaluation of aging degradation of structural components

    SciTech Connect (OSTI)

    Chopra, O.K.; Shack, W.J.

    1992-03-01

    Irradiation embrittlement of the neutron shield tank (NST) A212 Grade B steel from the Shippingport reactor, as well as thermal embrittlement of CF-8 cast stainless steel components from the Shippingport and KRB reactors, has been characterized. Increases in Charpy transition temperature (CTT), yield stress, and hardness of the NST material in the low-temperature low-flux environment are consistent with the test reactor data for irradiations at < 232{degrees}C. The shift in CTT is not as severe as that observed in surveillance samples from the High Flux Isotope Reactor (HFIR): however, it shows very good agreement with the results for HFIR A212-B steel irradiated in the Oak Ridge Research Reactor. The results indicate that fluence rate has not effect on radiation embrittlement at rates as low as 2 {times} 10{sup 8} n/cm{sup 2}{center_dot}s at the low operating temperature of the Shippingport NST, i.e., 55{degrees}C. This suggest that radiation damage in Shippingport NST and HFIR surveillance samples may be different because of the neutron spectra and/or Cu and Ni content of the two materials. Cast stainless steel components show relatively modest decreases in fracture toughness and Charpy-impact properties and a small increase in tensile strength. Correlations for estimating mechanical properties of cast stainless steels predict accurate or slightly conservative values for Charpy-impact energy, tensile flow stress, fracture toughness J-R curve, and J{sub IC} of the materials. The kinetics of thermal embrittlement and degree of embrittlement at saturation, i.e., the minimum impact energy achieved after long-term aging, were established from materials that were aged further in the laboratory. The results were consistent with the estimates. The correlations successfully predict the mechanical properties of the Ringhals 2 reactor hot- and crossover-leg elbows (CF-8M steel) after service of {approx}15 y.

  5. Characterizing Radiation-Aged Polysiloxane-Silica Composites...

    Office of Scientific and Technical Information (OSTI)

    Resource Relation: Journal Name: Chemical ... ORGANIC, PHYSICAL AND ANALYTICAL ... CHEMISTRY; AGING; CHAINS; DECAY; MAGNETIZATION; NUCLEAR MAGNETIC RESONANCE; PHYSICS; ...

  6. Aging management guideline for commercial nuclear power plants - heat exchangers

    SciTech Connect (OSTI)

    Booker, S.; Lehnert, D.; Daavettila, N.; Palop, E.

    1994-06-01

    This Aging Management Guideline (AMG) describes recommended methods for effective detection and mitigation of age-related degradation mechanisms in commercial nuclear power plant heat exchangers important to license renewal. The intent of this AMG is to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR 54. This AMG is presented in a manner that allows personnel responsible for performance analysis and maintenance to compare their plant-specific aging mechanisms (expected or already experienced) and aging management program activities to the more generic results and recommendations presented herein.

  7. Weldable, age hardenable, austenitic stainless steel

    DOE Patents [OSTI]

    Brooks, J.A.; Krenzer, R.W.

    1975-07-22

    An age hardenable, austenitic stainless steel having superior weldability properties as well as resistance to degradation of properties in a hydrogen atmosphere is described. It has a composition of from about 24.0 to about 34.0 weight percent (w/o) nickel, from about 13.5 to about 16.0 w/o chromium, from about 1.9 to about 2.3 w/o titanium, from about 1.0 to about 1.5 w/ o molybdenum, from about 0.01 to about 0.05 w/o carbon, from about 0 to about 0.25 w/o manganese, from about 0 to about 0.01 w/o phosphorous and preferably about 0.005 w/o maximum, from about 0 to about 0.010 w/o sulfur and preferably about 0.005 w/o maximum, from about 0 to about 0.25 w/o silicon, from about 0.1 to about 0.35 w/o aluminum, from about 0.10 to about 0.50 w/o vanadium, from about 0 to about 0.0015 w/o boron, and the balance essentially iron. (auth)

  8. Non-uniform Aging on Super Duty Diesel Truck Aged Urea Cu/Zeolite SCR

    Broader source: Energy.gov (indexed) [DOE]

    Catalysts | Department of Energy Cu/Zeolite SCR catalysts aged for 50k miles on a Super Duty diesel truck PDF icon deer10_cheng.pdf More Documents & Publications Deactivation Mechanisms of Base Metal/Zeolite Urea Selective Catalytic Reduction Materials, and Development of Zeolite-Based Hydrocarbon Adsorber Materials Deactivation Mechanisms of Base Metal/Zeolite Urea Selective Catalytic Reduction Materials, and Development of Zeolite-Based Hydrocarbon Adsorber Materials Understanding the

  9. LEAVING THE DARK AGES WITH AMIGA

    SciTech Connect (OSTI)

    Manrique, Alberto; Salvador-Sol, Eduard; Juan, Enric; Rozas, Jos Mara; Sagrist, Antoni; Casteels, Kevin; Hatziminaoglou, Evanthia; Bruzual, Gustavo; Magris, Gladis

    2015-01-01

    We present an Analytic Model of Intergalactic-medium and GAlaxy (AMIGA) evolution since the dark ages. AMIGA is in the spirit of the popular semi-analytic models of galaxy formation, although it does not use halo merger trees but interpolates halo properties in grids that are progressively built. This strategy is less memory-demanding and allows one to start modeling at sufficiently high redshifts and low halo masses to have trivial boundary conditions. The number of free parameters is minimized by making a causal connection between physical processes usually treated as independent of each other, which leads to more reliable predictions. However, the strongest points of AMIGA are the following: (1) the inclusion of molecular cooling and metal-poor, population III (Pop III) stars with the most dramatic feedback and (2) accurate follow up of the temperature and volume filling factor of neutral, singly ionized, and doubly ionized regions, taking into account the distinct halo mass functions in those environments. We find the following general results. Massive Pop III stars determine the intergalactic medium metallicity and temperature, and the growth of spheroids and disks is self-regulated by that of massive black holes (MBHs) developed from the remnants of those stars. However, the properties of normal galaxies and active galactic nuclei appear to be quite insensitive to Pop III star properties due to the much higher yield of ordinary stars compared to Pop III stars and the dramatic growth of MBHs when normal galaxies begin to develop, which cause the memory loss of the initial conditions.

  10. Space-Age Ceramics Get Their Toughest Test

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Space-Age Ceramics Get Their Toughest Test Space-Age Ceramics Get Their Toughest Test Print Wednesday, 17 April 2013 07:23 Advanced ceramic composites can withstand the ultrahigh operational temperatures projected for hypersonic jet and next-generation gas-turbine engines, but real-time analysis of the mechanical properties of these space-age materials at ultrahigh temperatures has been a challenge-until now. Researchers have developed the first testing facility that enables microtomography of

  11. Space-Age Ceramics Get Their Toughest Test

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Space-Age Ceramics Get Their Toughest Test Space-Age Ceramics Get Their Toughest Test Print Tuesday, 11 December 2012 14:54 Advanced ceramic composites can withstand the ultrahigh operational temperatures projected for hypersonic jet and next generation gas turbine engines, but real-time analysis of the mechanical properties of these space-age materials at ultrahigh temperatures has been a challenge - until now. Berkeley Lab and UC Berkeley researchers have developed the first testing facility

  12. Variation of the radiative properties during black carbon aging...

    Office of Scientific and Technical Information (OSTI)

    A theoretical black carbon (BC) aging model is developed to account for three typical evolution stages, namely, freshly emitted aggregates, coated BC by soluble material, and BC ...

  13. An Accelerated Aging Method for Diesel Exhaust Aftertreatment...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    An Accelerated Aging Method for Diesel Exhaust Aftertreatment Systems Poster presented at the 16th Directions in Engine-Efficiency and Emissions Research (DEER) Conference in ...

  14. Rapid Aging Protocols for Diesel Aftertreatment Devices: NOx...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Rapid Aging Protocols for Diesel Aftertreatment Devices: NOx Abatement Catalysts Poster presentation at the 2007 Diesel Engine-Efficiency & Emissions Research Conference (DEER ...

  15. Aging Management Program for Stainless Steel Dry Storage System Canisters

    SciTech Connect (OSTI)

    Dunn, Darrell S.; Lin, Bruce P.; Meyer, Ryan M.; Anderson, Michael T.

    2015-06-01

    This is a conference paper presenting an aging management program for stainless steel dry storage system canisters. NRC is lead author of paper. PNNL provided input.

  16. The Development of Rapid Aging and Poisoning Protocols for Diesel...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    More Documents & Publications CLEERS Aftertreatment Modeling and Analysis Effect of Thermal Aging on NO oxidation and NOx storage in a Fully-Formulated Lean NOx Trap CLEERS ...

  17. Quadrennial Energy Review Storage: Is It Finally Coming of Age...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Powering forward. Together. July 11, 2014 Department of Energy Quadrennial Energy Review Storage: Is It Finally Coming of Age? Arlen Orchard, General Manager & CEO * About SMUD * ...

  18. Space-Age Ceramics Get Their Toughest Test

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Space-Age Ceramics Get Their Toughest Test Print Advanced ceramic composites can withstand the ultrahigh operational temperatures projected for hypersonic jet and next-generation...

  19. Age Inversiones in Media Ambiente AIMA | Open Energy Information

    Open Energy Info (EERE)

    Inversiones in Media Ambiente AIMA Jump to: navigation, search Name: Age Inversiones in Media Ambiente (AIMA) Place: Spain Product: Invests in projects that aim to generate energy...

  20. Y-12 hosts NNSA Aging Infrastructure Workshop | Y-12 National...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    from across the NNSA complex and private industry gathered in Oak Ridge to discuss lessons learned and brainstorm solutions for dealing with the aging nuclear...

  1. Y-12 hosts NNSA aging infrastructure workshop | National Nuclear...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    throughout NNSA and private industry recently gathered in Oak Ridge, Tenn., to discuss lessons learned and brainstorm solutions for dealing with the aging nuclear...

  2. Health, Productivity and Safety in the Workforce: Does Age Make...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... REPORTED HEALTH CONDITIONS* Age** N (%) Depression ***LD Sleeping Problems LD Overweight ... example, 16.3% workers 50 reported depression and had 131.58 (per 100 FTEs) fewer ...

  3. Theoretical foundation for measuring the groundwater age distribution.

    SciTech Connect (OSTI)

    Gardner, William Payton; Arnold, Bill Walter

    2014-01-01

    In this study, we use PFLOTRAN, a highly scalable, parallel, flow and reactive transport code to simulate the concentrations of 3H, 3He, CFC-11, CFC-12, CFC-113, SF6, 39Ar, 81Kr, 4He and themean groundwater age in heterogeneous fields on grids with an excess of 10 million nodes. We utilize this computational platform to simulate the concentration of multiple tracers in high-resolution, heterogeneous 2-D and 3-D domains, and calculate tracer-derived ages. Tracer-derived ages show systematic biases toward younger ages when the groundwater age distribution contains water older than the maximum tracer age. The deviation of the tracer-derived age distribution from the true groundwater age distribution increases with increasing heterogeneity of the system. However, the effect of heterogeneity is diminished as the mean travel time gets closer the tracer age limit. Age distributions in 3-D domains differ significantly from 2-D domains. 3D simulations show decreased mean age, and less variance in age distribution for identical heterogeneity statistics. High-performance computing allows for investigation of tracer and groundwater age systematics in high-resolution domains, providing a platform for understanding and utilizing environmental tracer and groundwater age information in heterogeneous 3-D systems. Groundwater environmental tracers can provide important constraints for the calibration of groundwater flow models. Direct simulation of environmental tracer concentrations in models has the additional advantage of avoiding assumptions associated with using calculated groundwater age values. This study quantifies model uncertainty reduction resulting from the addition of environmental tracer concentration data. The analysis uses a synthetic heterogeneous aquifer and the calibration of a flow and transport model using the pilot point method. Results indicate a significant reduction in the uncertainty in permeability with the addition of environmental tracer data, relative to the use of hydraulic measurements alone. Anthropogenic tracers and their decay products, such as CFC11, 3H, and 3He, provide significant constraint oninput permeability values in the model. Tracer data for 39Ar provide even more complete information on the heterogeneity of permeability and variability in the flow system than the anthropogenic tracers, leading to greater parameter uncertainty reduction.

  4. Aging Behavior and Performance Projections for a Polysulfide Elastomer

    SciTech Connect (OSTI)

    Celina, Mathias C.; Giron, Nicholas Henry; Quintana, Adam

    2015-05-01

    The accelerated aging behavior and aging state of a 30 year old field retrieved polysulfide elastomer was examined. The material is used as an environmental thread sealant for a stainless steel bolt in a steel threaded insert in an aluminum assembly. It is a two component curable polysulfide elastomer that is commercially available in a similar formulation as was applied 30 years ago. The primary goal of this study was to establish if aging over 30 years under moderate aging conditions (mostly ambient temperature and humidity) resulted in significant property changes, or if accelerated aging could identify developing aging pathways which would prevent the extended use of this material. The aging behavior of this material was examined in three ways: A traditional accelerated thermo-oxidative aging study between 95 to 140°C which focused on physical and chemical properties changes, an evaluation of the underlying oxidation rates between RT and 125°C, and an assessment of the aging state of a small 30 year old sample. All three data sets were used to establish aging characteristics, their time evolution, and to extrapolate the observed behavior to predict performance limits at RT. The accelerated aging study revealed a relatively high average activation energy of ~130 kJ/mol which gives overconfident performance predictions. Oxidation rates showed a decreasing behavior with aging time and a lower E a of ~84 kJ/mol from time - temperature superposition , but also predicted sufficient additional performance at RT. Consistent with these projections for extended RT performance, only small changes were observed for the 30 year old material. Extrapolations using this partially aged material also predict ongoing use as a viable option. Unexpected RT degradation could only develop into a concern should the oxidation rate not trend lower over time as was observed at elevated temperature. Considering all data acquired in this limited aging study , there are no immediately apparent concerns with this material for ongoing use. ACKNOWLEDGEMENTS We thank Lisa Deibler for providing us with a small sample of field aged and new commercial material.

  5. A Proof of Concept: Grizzly, the LWRS Program Materials Aging and

    Energy Savers [EERE]

    Degradation Pathway Main Simulation Tool | Department of Energy A Proof of Concept: Grizzly, the LWRS Program Materials Aging and Degradation Pathway Main Simulation Tool A Proof of Concept: Grizzly, the LWRS Program Materials Aging and Degradation Pathway Main Simulation Tool Nuclear power currently provides a significant fraction of the United States' non- carbon emitting power generation. In future years, nuclear power must continue to generate a significant portion of the nation's

  6. Accelerated Aging of Roofing Materials - 2013 BTO Peer Review | Department

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of Energy Materials - 2013 BTO Peer Review Accelerated Aging of Roofing Materials - 2013 BTO Peer Review Emerging Technologies Project for the 2013 Building Technologies Office's Program Peer Review PDF icon emrgtech24_destaillats_040413.pdf More Documents & Publications Accelerated Aging of Roofing Materials Stay-Clean and Durable White Elastomeric Roof Coatings New Cool Roof Coatings and Affordable Cool Color Asphalt

  7. Age and gender specific biokinetic model for strontium in humans

    SciTech Connect (OSTI)

    Shagina, N. B.; Tolstykh, E. I.; Degteva, M. O.; Anspaugh, L. R.; Napier, Bruce A.

    2015-03-01

    A biokinetic model for strontium in humans is necessary for quantification of internal doses due to strontium radioisotopes. The ICRP-recommended biokinetic model for strontium has limitation for use in a population study, because it is not gender specific and does not cover all age ranges. The extensive Techa River data set on 90Sr in humans (tens of thousands of measurements) is a unique source of data on long-term strontium retention for men and women of all ages at intake. These, as well as published data, were used for evaluation of age- and gender-specific parameters for a new compartment biokinetic model for strontium (Sr-AGe model). The Sr-AGe model has similar structure as the ICRP model for the alkaline earth elements. The following parameters were mainly reevaluated: gastro-intestinal absorption and parameters related to the processes of bone formation and resorption defining calcium and strontium transfers in skeletal compartments. The Sr-AGe model satisfactorily describes available data sets on strontium retention for different kinds of intake (dietary and intravenous) at different ages (080 years old) and demonstrates good agreement with data sets for different ethnic groups. The Sr-AGe model can be used for dose assessment in epidemiological studies of general population exposed to ingested strontium radioisotopes.

  8. Nuclear power plant Generic Aging Lessons Learned (GALL). Appendix B

    SciTech Connect (OSTI)

    Kasza, K.E.; Diercks, D.R.; Holland, J.W.; Choi, S.U.

    1996-12-01

    The purpose of this generic aging lessons learned (GALL) review is to provide a systematic review of plant aging information in order to assess materials and component aging issues related to continued operation and license renewal of operating reactors. Literature on mechanical, structural, and thermal-hydraulic components and systems reviewed consisted of 97 Nuclear Plant Aging Research (NPAR) reports, 23 NRC Generic Letters, 154 Information Notices, 29 Licensee Event Reports (LERs), 4 Bulletins, and 9 Nuclear Management and Resources Council Industry Reports (NUMARC IRs) and literature on electrical components and systems reviewed consisted of 66 NPAR reports, 8 NRC Generic Letters, 111 Information Notices, 53 LERs, 1 Bulletin, and 1 NUMARC IR. More than 550 documents were reviewed. The results of these reviews were systematized using a standardized GALL tabular format and standardized definitions of aging-related degradation mechanisms and effects. The tables are included in volume s 1 and 2 of this report. A computerized data base has also been developed for all review tables and can be used to expedite the search for desired information on structures, components, and relevant aging effects. A survey of the GALL tables reveals that all ongoing significant component aging issues are currently being addressed by the regulatory process. However, the aging of what are termed passive components has been highlighted for continued scrutiny. This report consists of Volume 2, which consists of the GALL literature review tables for the NUMARC Industry Reports reviewed for the report.

  9. Seismic ruggedness of aged electrical components: Final report (Phase 2)

    SciTech Connect (OSTI)

    Gleason, J.F.

    1987-01-01

    Seismic tests on new and aged components have shown that, for many types of commonly used nuclear plant electrical components, deterioration due to aging does not significantly affect the ability of the components to function during and after a seismic event. This was demonstrated for capacitors, circuit breakers, contactors (motor starters), control station assemblies, electronic alarms, electronics, fuses, fuse blocks, inductors, meters, motors, pressure transmitters, power supplies, relays, RTDs, solenoid valves, terminal blocks, time delay relays, transformers and switches. A few switch types (limit, pressure and rotary) were observed to be more prone to contact chatter in an aged condition than in an unaged condition. However, the ability of these devices to switch during and after shaking was not affected by aging. These results can be referenced to eliminate the cost of aging prior to seismic qualification testing for many types of electrical components.

  10. Aging management guideline for commercial nuclear power plants-pumps

    SciTech Connect (OSTI)

    Booker, S.; Katz, D.; Daavettila, N.; Lehnert, D.

    1994-03-01

    This Aging Management Guideline (AMG) describes recommended methods for effective detection and mitigation of age-related degradation mechanisms in BWR and PWR commercial nuclear power plant pumps important to license renewal. The intent of this AMG is to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR Part 54. This AMG is presented in a manner that allows personnel responsible for performance analysis and maintenance to compare their plant-specific aging mechanisms (expected or already experienced) and aging management program activities to the more generic results and recommendations presented herein.

  11. Recommendations for the treatment of aging in standard technical specifications

    SciTech Connect (OSTI)

    Orton, R.D.; Allen, R.P.

    1995-09-01

    As part of the US Nuclear Regulatory Commission`s Nuclear Plant Aging Research Program, Pacific Northwest Laboratory (PNL) evaluated the standard technical specifications for nuclear power plants to determine whether the current surveillance requirements (SRs) were effective in detecting age-related degradation. Nuclear Plant Aging Research findings for selected systems and components were reviewed to identify the stressors and operative aging mechanisms and to evaluate the methods available to detect, differentiate, and trend the resulting aging degradation. Current surveillance and testing requirements for these systems and components were reviewed for their effectiveness in detecting degraded conditions and for potential contributions to premature degradation. When the current surveillance and testing requirements appeared ineffective in detecting aging degradation or potentially could contribute to premature degradation, a possible deficiency in the SRs was identified that could result in undetected degradation. Based on this evaluation, PNL developed recommendations for inspection, surveillance, trending, and condition monitoring methods to be incorporated in the SRs to better detect age- related degradation of these selected systems and components.

  12. An aging study of wire chambers with dimethyl ether

    SciTech Connect (OSTI)

    Jibaly, M.; Chrusch, P. Jr.; Hilgenberg, G.; Majewski, S.; Wojcik, R.; Sauli, F.; Gaudaen, J.

    1989-02-01

    The authors report results on the aging of different types of resistive and non-resistive wires in wire chambers filled with dimethyl ether (DME) of varying degrees of purity. Among the Freon impurities detected in our DME batches, only Freon-11 was found to contribute to the aging process. Of the resistive wires, Nicotin and Stablohm produced fast aging, whereas stainless steel withstood extended irradiation in purified DME (up to 1 C/cm) without any apparent damage. Gold-plated tungsten and molybdenum wires produced results comparable to those of the stainless steel.

  13. Fracture and thermal aging of resin-filled silicone elastomers...

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Search Results Journal Article: Fracture and thermal aging of resin-filled ... Publication Date: 2016-03-24 OSTI Identifier: 1236865 Resource Type: Journal Article ...

  14. Enzyme Structure Provides Insights into Cancer and Aging

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Provides Insights into Cancer and Aging Print XPD helicase is an enzyme that unwinds the DNA double helix; it is one component of an essential repair mechanism that maintains the...

  15. Science on Saturday attracts science fans of all ages | Princeton...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science on Saturday attracts science fans of all ages By Jeanne Jackson DeVoe January 28, 2013 Tweet Widget Google Plus One Share on Facebook Joshua E. G. Peek, a Hubble Fellow at ...

  16. Fact #558: February 16, 2009 Transit Vehicle Age and Cost

    Broader source: Energy.gov [DOE]

    Heavy rail cars have the greatest longevity of the transit vehicles listed below with an average vehicle age of more than 22 years. However, in terms of cost for purchasing a new rail car, heavy...

  17. Managing Aging Effects on Dry Cask Storage Systems for Extended...

    Office of Environmental Management (EM)

    dry cask storage system designs; and 4) AMPs and TLAAs for the SSCs that are important to safety in the DCSS designs. PDF icon Managing Aging Effects on Dry Cask Storage Systems...

  18. Tensile-property characterization of thermally aged cast stainless steels

    SciTech Connect (OSTI)

    Michaud, W.F.; Toben, P.T.; Soppet, W.K.; Chopra, O.K.

    1994-02-01

    The effect of thermal aging on tensile properties of cast stainless steels during service in light water reactors has been evaluated. Tensile data for several experimental and commercial heats of cast stainless steels are presented. Thermal aging increases the tensile strength of these steels. The high-C Mo-bearing CF-8M steels are more susceptible to thermal aging than the Mo-free CF-3 or CF-8 steels. A procedure and correlations are presented for predicting the change in tensile flow and yield stresses and engineering stress-vs.-strain curve of cast stainless steel as a function of time and temperature of service. The tensile properties of aged cast stainless steel are estimated from known material information, i.e., chemical composition and the initial tensile strength of the steel. The correlations described in this report may be used for assessing thermal embrittlement of cast stainless steel components.

  19. Enzyme Structure Provides Insights into Cancer and Aging

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Enzyme Structure Provides Insights into Cancer and Aging Print XPD helicase is an enzyme that unwinds the DNA double helix; it is one component of an essential repair mechanism...

  20. Maximum Entry and Mandatory Separation Ages for Certain Security Employees

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2001-10-11

    The Policy in response to government-wide Office of Personnel Management regulations regarding establishment of mandatory retirement ages for employees in certain security related positions. Superseded by DOE P 310.1 Admin Chg 1, 12-1-11.

  1. Light Water Reactor Sustainability Program: Materials Aging and Degradation

    Energy Savers [EERE]

    Technical Program Plan | Department of Energy Program: Materials Aging and Degradation Technical Program Plan Light Water Reactor Sustainability Program: Materials Aging and Degradation Technical Program Plan Components serving in a nuclear reactor plant must withstand a very harsh environment including extended time at temperature, neutron irradiation, stress, and/or corrosive media. The many modes of degradation are complex and vary depending on location and material. However,

  2. Enzyme Structure Provides Insights into Cancer and Aging

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Enzyme Structure Provides Insights into Cancer and Aging Print XPD helicase is an enzyme that unwinds the DNA double helix; it is one component of an essential repair mechanism that maintains the integrity of DNA. XPD is unique, however, in that pinpoint mutations of this single protein are responsible for three different human diseases: in xeroderma pigmentosum (XP), extreme sensitivity to sunlight promotes cancer; Cockayne syndrome (CS) involves stunted growth and premature aging;

  3. Enzyme Structure Provides Insights into Cancer and Aging

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Enzyme Structure Provides Insights into Cancer and Aging Print XPD helicase is an enzyme that unwinds the DNA double helix; it is one component of an essential repair mechanism that maintains the integrity of DNA. XPD is unique, however, in that pinpoint mutations of this single protein are responsible for three different human diseases: in xeroderma pigmentosum (XP), extreme sensitivity to sunlight promotes cancer; Cockayne syndrome (CS) involves stunted growth and premature aging;

  4. Enzyme Structure Provides Insights into Cancer and Aging

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Enzyme Structure Provides Insights into Cancer and Aging Print XPD helicase is an enzyme that unwinds the DNA double helix; it is one component of an essential repair mechanism that maintains the integrity of DNA. XPD is unique, however, in that pinpoint mutations of this single protein are responsible for three different human diseases: in xeroderma pigmentosum (XP), extreme sensitivity to sunlight promotes cancer; Cockayne syndrome (CS) involves stunted growth and premature aging;

  5. Enzyme Structure Provides Insights into Cancer and Aging

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Enzyme Structure Provides Insights into Cancer and Aging Print XPD helicase is an enzyme that unwinds the DNA double helix; it is one component of an essential repair mechanism that maintains the integrity of DNA. XPD is unique, however, in that pinpoint mutations of this single protein are responsible for three different human diseases: in xeroderma pigmentosum (XP), extreme sensitivity to sunlight promotes cancer; Cockayne syndrome (CS) involves stunted growth and premature aging;

  6. Enzyme Structure Provides Insights into Cancer and Aging

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Enzyme Structure Provides Insights into Cancer and Aging Enzyme Structure Provides Insights into Cancer and Aging Print Wednesday, 25 February 2009 00:00 XPD helicase is an enzyme that unwinds the DNA double helix; it is one component of an essential repair mechanism that maintains the integrity of DNA. XPD is unique, however, in that pinpoint mutations of this single protein are responsible for three different human diseases: in xeroderma pigmentosum (XP), extreme sensitivity to sunlight

  7. Modelling aging effects on a thermal cycling absorption process column

    SciTech Connect (OSTI)

    Laquerbe, C.; Contreras, S.; Demoment, J.

    2008-07-15

    Palladium coated on alumina is used in hydrogen separation systems operated at CEA/Valduc, and more particularly in Thermal Cycling Absorption Process columns. With such materials, tritium decay is known to induce aging effects which have direct side effects on hydrogen isotopes absorption isotherms. Furthermore in a TCAP column, aging occurs in an heterogeneous way. The possible impacts of these intrinsic material evolutions on the separation performances are investigated here through a numerical approach. (authors)

  8. Enzyme Structure Provides Insights into Cancer and Aging

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Enzyme Structure Provides Insights into Cancer and Aging Print XPD helicase is an enzyme that unwinds the DNA double helix; it is one component of an essential repair mechanism that maintains the integrity of DNA. XPD is unique, however, in that pinpoint mutations of this single protein are responsible for three different human diseases: in xeroderma pigmentosum (XP), extreme sensitivity to sunlight promotes cancer; Cockayne syndrome (CS) involves stunted growth and premature aging;

  9. Enzyme Structure Provides Insights into Cancer and Aging

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Enzyme Structure Provides Insights into Cancer and Aging Print XPD helicase is an enzyme that unwinds the DNA double helix; it is one component of an essential repair mechanism that maintains the integrity of DNA. XPD is unique, however, in that pinpoint mutations of this single protein are responsible for three different human diseases: in xeroderma pigmentosum (XP), extreme sensitivity to sunlight promotes cancer; Cockayne syndrome (CS) involves stunted growth and premature aging;

  10. Characterizing Radiation-Aged Polysiloxane-Silica Composites: Identifying

    Office of Scientific and Technical Information (OSTI)

    Changes in Network Topology via 1H NMR (Journal Article) | SciTech Connect Journal Article: Characterizing Radiation-Aged Polysiloxane-Silica Composites: Identifying Changes in Network Topology via 1H NMR Citation Details In-Document Search Title: Characterizing Radiation-Aged Polysiloxane-Silica Composites: Identifying Changes in Network Topology via 1H NMR Characterizing and quantifying changes in elastomeric materials upon exposure to harsh environments is important in the estimation of

  11. Space-Age Ceramics Get Their Toughest Test

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Space-Age Ceramics Get Their Toughest Test Print Advanced ceramic composites can withstand the ultrahigh operational temperatures projected for hypersonic jet and next-generation gas-turbine engines, but real-time analysis of the mechanical properties of these space-age materials at ultrahigh temperatures has been a challenge-until now. Researchers have developed the first testing facility that enables microtomography of ceramic composites under controlled loads at ultrahigh temperatures and in

  12. Space-Age Ceramics Get Their Toughest Test

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Space-Age Ceramics Get Their Toughest Test Print Advanced ceramic composites can withstand the ultrahigh operational temperatures projected for hypersonic jet and next-generation gas-turbine engines, but real-time analysis of the mechanical properties of these space-age materials at ultrahigh temperatures has been a challenge-until now. Researchers have developed the first testing facility that enables microtomography of ceramic composites under controlled loads at ultrahigh temperatures and in

  13. Space-Age Ceramics Get Their Toughest Test

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Space-Age Ceramics Get Their Toughest Test Print Advanced ceramic composites can withstand the ultrahigh operational temperatures projected for hypersonic jet and next-generation gas-turbine engines, but real-time analysis of the mechanical properties of these space-age materials at ultrahigh temperatures has been a challenge-until now. Researchers have developed the first testing facility that enables microtomography of ceramic composites under controlled loads at ultrahigh temperatures and in

  14. Space-Age Ceramics Get Their Toughest Test

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Space-Age Ceramics Get Their Toughest Test Print Advanced ceramic composites can withstand the ultrahigh operational temperatures projected for hypersonic jet and next-generation gas-turbine engines, but real-time analysis of the mechanical properties of these space-age materials at ultrahigh temperatures has been a challenge-until now. Researchers have developed the first testing facility that enables microtomography of ceramic composites under controlled loads at ultrahigh temperatures and in

  15. Space-Age Ceramics Get Their Toughest Test

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Space-Age Ceramics Get Their Toughest Test Print Advanced ceramic composites can withstand the ultrahigh operational temperatures projected for hypersonic jet and next-generation gas-turbine engines, but real-time analysis of the mechanical properties of these space-age materials at ultrahigh temperatures has been a challenge-until now. Researchers have developed the first testing facility that enables microtomography of ceramic composites under controlled loads at ultrahigh temperatures and in

  16. Space-Age Ceramics Get Their Toughest Test

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Space-Age Ceramics Get Their Toughest Test Print Advanced ceramic composites can withstand the ultrahigh operational temperatures projected for hypersonic jet and next-generation gas-turbine engines, but real-time analysis of the mechanical properties of these space-age materials at ultrahigh temperatures has been a challenge-until now. Researchers have developed the first testing facility that enables microtomography of ceramic composites under controlled loads at ultrahigh temperatures and in

  17. Space-Age Ceramics Get Their Toughest Test

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Space-Age Ceramics Get Their Toughest Test Print Advanced ceramic composites can withstand the ultrahigh operational temperatures projected for hypersonic jet and next-generation gas-turbine engines, but real-time analysis of the mechanical properties of these space-age materials at ultrahigh temperatures has been a challenge-until now. Researchers have developed the first testing facility that enables microtomography of ceramic composites under controlled loads at ultrahigh temperatures and in

  18. Accelerated Aging of Roofing Materials | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Accelerated Aging of Roofing Materials Accelerated Aging of Roofing Materials Addthis 1 of 2 Berkeley Lab Heat Island Group chemist Mohamad Sleiman prepares to insert clean and soiled roofing specimens into a weatherometer. The weatherometer simulates exposure to heat, moisture, and UV radiation. Image: Heat Island Group, Lawrence Berkeley National Laboratory 2 of 2 Berkeley Lab Heat Island Group chemist Mohamad Sleiman configures a weatherometer to simulate the effects of heat, moisture, and UV

  19. Age-related degradation of Westinghouse 480-volt circuit breakers

    SciTech Connect (OSTI)

    Subudhi, M.; Shier, W.; MacDougall, E. )

    1990-07-01

    An aging assessment of Westinghouse DS-series low-voltage air circuit breakers was performed as part of the Nuclear Plant Aging Research (NPAR) program. The objectives of this study are to characterize age-related degradation within the breaker assembly and to identify maintenance practices to mitigate their effect. Since this study has been promulgated by the failures of the reactor trip breakers at the McGuire Nuclear Station in July 1987, results relating to the welds in the breaker pole lever welds are also discussed. The design and operation of DS-206 and DS-416 breakers were reviewed. Failure data from various national data bases were analyzed to identify the predominant failure modes, causes, and mechanisms. Additional operating experiences from one nuclear station and two industrial breaker-service companies were obtained to develop aging trends of various subcomponents. The responses of the utilities to the NRC Bulletin 88-01, which discusses the center pole lever welds, were analyzed to assess the final resolution of failures of welds in the reactor trips. Maintenance recommendations, made by the manufacturer to mitigate age-related degradation were reviewed, and recommendations for improving the monitoring of age-related degradation are discussed. As described in Volume 2 of this NUREG, the results from a test program to assess degradation in breaker parts through mechanical cycling are also included. The testing has characterized the cracking of center-pole lever welds, identified monitoring techniques to determine aging in breakers, and provided information to augment existing maintenance programs. Recommendations to improve breaker reliability using effective maintenance, testing, and inspection programs are suggested. 13 refs., 21 figs., 8 tabs.

  20. Managing aging in nuclear power plants: Insights from NRC maintenance team inspection reports

    SciTech Connect (OSTI)

    Fresco, A.; Subudhi, M.; Gunther, W.; Grove, E.; Taylor, J.

    1993-12-01

    A plant`s maintenance program is the principal vehicle through which age-related degradation is managed. From 1988 to 1991, the NRC evaluated the maintenance program of every nuclear power plant in the United States. Forty-four out of a total of 67 of the reports issued on these in-depth team inspections were reviewed for insights into the strengths and weaknesses of the programs as related to the need to understand and manage the effects of aging on nuclear plant systems, structures, and components. Relevant information was extracted from these inspection reports and sorted into several categories, including Specific Aging Insights, Preventive Maintenance, Predictive Maintenance and Condition Monitoring, Post Maintenance Testing, Failure Trending, Root Cause Analysis and Usage of Probabilistic Risk Assessment in the Maintenance Process. Specific examples of inspection and monitoring techniques successfully used by utilities to detect degradation due to aging have been identified. The information also was sorted according to systems and components, including: Auxiliary Feedwater, Main Feedwater, High Pressure Injection for both BWRs and PWRs, Service Water, Instrument Air, and Emergency Diesel Generator Air Start Systems, and Emergency Diesel Generators Air Start Systems, emergency diesel generators, electrical components such as switchgear, breakers, relays, and motor control centers, motor operated valves and check valves. This information was compared to insights gained from the Nuclear Plant Aging Research (NPAR) Program. Attributes of plant maintenance programs where the NRC inspectors felt that improvement was needed to properly address the aging issue also are discussed.

  1. Nuclear plant-aging research on reactor protection systems

    SciTech Connect (OSTI)

    Meyer, L.C.

    1988-01-01

    This report presents the rsults of a review of the Reactor Trip System (RTS) and the Engineered Safety Feature Actuating System (ESFAS) operating experiences reported in Licensee Event Reports (LER)s, the Nuclear Power Experience data base, Nuclear Plant Reliability Data System, and plant maintenance records. Our purpose is to evaluate the potential significance of aging, including cycling, trips, and testing as contributors to degradation of the RTS and ESFAS. Tables are presented that show the percentage of events for RTS and ESFAS classified by cause, components, and subcomponents for each of the Nuclear Steam Supply System vendors. A representative Babcock and Wilcox plant was selected for detailed study. The US Nuclear Regulatory Commission's Nuclear Plant Aging Research guidelines were followed in performing the detailed study that identified materials susceptible to aging, stressors, environmental factors, and failure modes for the RTS and ESFAS as generic instrumentation and control systems. Functional indicators of degradation are listed, testing requirements evaluated, and regulatory issues discussed.

  2. Age constraints on fluid inclusions in calcite at Yucca Mountain

    SciTech Connect (OSTI)

    Neymark, Leonid A.; Amelin, Yuri V.; Paces, James B.; Peterman, Zell E.; Whelan, Joseph F.

    2001-04-29

    The {sup 207}Pb/{sup 235}U ages for 14 subsamples of opal or chalcedony layers younger than calcite formed at elevated temperature range between 1.88 {+-} 0.05 and 9.7 {+-} 1.5 Ma with most values older than 6-8 Ma. These data indicate that fluids with elevated temperatures have not been present in the unsaturated zone at Yucca Mountain since about 1.9 Ma and most likely since 6-8 Ma. Discordant U-Pb isotope data for chalcedony subsamples representing the massive silica stage in the formation of the coatings are interpreted using a model of the diffusive loss of U decay products. The model gives an age estimate for the time of chalcedony formation around 10-11 Ma, which overlaps ages of clay minerals formed in tuffs below the water table at Yucca Mountain during the Timber Mountain thermal event.

  3. Diverse ages and origins of basement complexes, Luzon, Philippines

    SciTech Connect (OSTI)

    Geary, E.E.; Harrison, T.M.; Heizler, M.

    1988-04-01

    Geological field investigations and /sup 40/Ar//sup 39/Ar ages from two basement complexes in southeast Luzon document the first known occurrences of pre-Late Cretaceous age rocks in the eastern Philippines. However, individual components within the two complexes vary in age from Late Jurassic (Caramoan basement complex) to Early Cretaceous and early Miocene (Camarines Norte-Calaguas Islands basement complex). These and other data show that southeast Luzon basement complexes are genetically diverse, and they indicate that the concept of an old, autochthonous basement in the Philippines is open to question. This supports the hypothesis that the Philippine Archipelago is an amalgamation of allochthonous Mesozoic and Cenozoic island-arc, ocean-basin, and continental fragments that were assembled during the Tertiary.

  4. Final Report Inspection of Aged/Degraded Containments Program.

    SciTech Connect (OSTI)

    Naus, Dan J; Ellingwood, B R; Oland, C Barry

    2005-09-01

    The Inspection of Aged/Degraded Containments Program had primary objectives of (1) understanding the significant factors relating corrosion occurrence, efficacy of inspection, and structural capacity reduction of steel containments and liners of reinforced concrete containments; (2) providing the United States Nuclear Regulatory Commission (USNRC) reviewers a means of establishing current structural capacity margins or estimating future residual structural capacity margins for steel containments, and concrete containments as limited by liner integrity; (3) providing recommendations, as appropriate, on information to be requested of licensees for guidance that could be utilized by USNRC reviewers in assessing the seriousness of reported incidences of containment degradation; and (4) providing technical assistance to the USNRC (as requested) related to concrete technology. Primary program accomplishments have included development of a degradation assessment methodology; reviews of techniques and methods for inspection and repair of containment metallic pressure boundaries; evaluation of high-frequency acoustic imaging, magnetostrictive sensor, electromagnetic acoustic transducer, and multimode guided plate wave technologies for inspection of inaccessible regions of containment metallic pressure boundaries; development of a continuum damage mechanics-based approach for structural deterioration; establishment of a methodology for reliability-based condition assessments of steel containments and liners; and fragility assessments of steel containments with localized corrosion. In addition, data and information assembled under this program has been transferred to the technical community through review meetings and briefings, national and international conference participation, technical committee involvement, and publications of reports and journal articles. Appendix A provides a listing of program reports, papers, and publications; and Appendix B contains a listing of program-related presentations.

  5. Brain surgery breathes new life into aging plants

    SciTech Connect (OSTI)

    Makansi, J.

    2006-04-15

    Unlike managing the human aging process, extending the life of a power plant often includes brain surgery, modernizing its control and automation system. Lately, such retrofits range from wholesale replacing of existing controls to the addition of specific control elements that help optimize performance. Pending revisions to safety codes and cybersecurity issues also need to be considered. 4 figs.

  6. Aging of Alloy 617 at 650 and 750 Degrees C

    SciTech Connect (OSTI)

    Julian Benz; Thomas Lillo; Richard Wright

    2013-01-01

    Alloy 617 has been selected as the primary candidate for heat exchanger applications in advanced reactors. For the VHTR this application could require extended service up to a reactor outlet temperature of 950°C. A key hurdle to using this alloy in the VHTR heat exchanger application is qualifying the alloy for Section III of the ASME Boiler and Pressure Vessel Code. In order to Code qualify the material it is necessary to characterize the influence of long term aging on the mechanical behavior. Alloy 617 has been aged at 650 and 750°C for times up to 5300 hours. The microstructure after aging has been characterized using optical and transmission electron microscopies. It has been determined that in addition to carbides, a significant volume fraction of ?’ phase (Ni3Al) is formed at these temperatures. The ?’ does not contribute significantly to changing the tensile or impact properties of the aged material. It does, however, appear to increase creep resistance and impede creep crack growth.

  7. Accelerated Light Aging of PV Encapsulants | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    Correlation of Xenon Arc and Mirror Accelerated Outdoor Aging from 1993-1997 PDF icon pvmrw13_uvth_str_reid.pdf More Documents & Publications Literature Review of the Effects of UV Exposure on PV Modules Retrospective Benefit-Cost Evaluation of DOE Investment in Photovoltaic Energy Systems Retrospective Benefit-Cost Evaluation of DOE Investments in Photovoltaic Energy Systems

  8. Decreases in Human Semen Quality with Age Among Healthy Men

    SciTech Connect (OSTI)

    Eskenazi, B.; Wyrobek, A.J.; Kidd, S.A.; Moore, L.; Young, S.S.; Moore, D.

    2001-12-01

    The objective of this report is to characterize the associations between age and semen quality among healthy active men after controlling for identified covariates. Ninety-seven healthy, nonsmoking men between 22 and 80 years without known fertility problems who worked for or retired from a large research laboratory. There was a gradual decrease in all semen parameters from 22-80 years of age. After adjusting for covariates, volume decreased 0.03 ml per year (p = 0.001); sperm concentration decreased 2.5% per year (p = 0.005); total count decreased 3.6% per year of age (p < 0.001); motility decreased 0.7% per year (P < 0.001); progressive motility decreased 3.1% per year (p < 0.001); and total progressively motile sperm decreased 4.8% per year (p < 0.001). In a group of healthy active men, semen volume, sperm concentration, total sperm count, and sperm motility decrease continuously between 22-80 years of age, with no evidence of a threshold.

  9. Characterization of Field-Aged Exhaust Gas Recirculation Cooler Deposits |

    Broader source: Energy.gov (indexed) [DOE]

    Department of Energy Characterized field-aged exhaust gas recirculation coolers from 7 engine manufacturers, discussed differences and commonalities, and provided understanding of cooler fouling and prevention. PDF icon deer10_lance.pdf More Documents & Publications Materials Issues Associated with EGR Systems Materials Issues Associated with EGR Systems Materials Issues Associated with EGR Systems (Agreement ID:18571)

  10. Iodine Loading of NO Aged Silver Exchanged Mordenite

    SciTech Connect (OSTI)

    Patton, K. K.; Bruffey, S. H.; Jubin, J. T.; Walker, Jr., J. F.

    2014-09-30

    In an off-gas treatment system for used nuclear fuel processing, a solid sorbent will typically be exposed to a gas stream for months at a time. This gas stream may be at elevated temperature and could contain water vapor, gaseous nitrogen oxides (NO{sub x}), nitric acid vapors, and a variety of other constituents. For this reason, it is important to evaluate the effects of long-term exposure, or aging, on proposed sorbents. Silver exchanged mordenite (AgZ) is being studied at Oak Ridge National Laboratory (ORNL) to determine its iodine sorption capacity after long term exposure to increasingly more complex chemical environments. Studies previously conducted at ORNL investigated the effects of aging reduced silver exchanged mordenite (Ag{sup 0}Z) in dry air, moist air, and NO2. This study investigated the effects of extended exposure to nitric oxide (NO) gas on the iodine capture performance of Ag{sup 0}Z. A deep bed of Ag{sup 0}Z was aged in a 1% nitric oxide (NO) air stream, and portions of the bed were removed at pre-determined intervals. After being removed from the NO stream, each sample was loaded with iodine in a thin bed configuration. These samples were analyzed by neutron activation analysis (NAA) to quantify the iodine content in the sample. Samples were removed at one week and one month. A 78% decrease in sample capacity was seen after one week of exposure, with no further decrease observed after 1 month of aging. The observed loss in capacity is larger in magnitude than previous studies exposing Ag{sup 0}Z to dry air, moist air, or NO2 gas. The aging study was terminated after one month and repeated; this successfully demonstrated the reproducibility of the results.

  11. Investigation of Aging Mechanisms in Lean NOx Traps

    SciTech Connect (OSTI)

    Mark Crocker

    2010-03-31

    Lean NO{sub x} traps (LNTs) represent a promising technology for the abatement of NO{sub x} under lean conditions. Although LNTs are starting to find commercial application, the issue of catalyst durability remains problematic. LNT susceptibility to sulfur poisoning is the single most important factor determining effective catalyst lifetime. The NO{sub x} storage element of the catalyst has a greater affinity for SO{sub 3} than it does for NO{sub 2}, and the resulting sulfate is more stable than the stored nitrate. Although this sulfate can be removed from the catalyst by means of high temperature treatment under rich conditions, the required conditions give rise to deactivation mechanisms such as precious metal sintering, total surface area loss, and solid state reactions between the various oxides present. The principle objective of this project was to improve understanding of the mechanisms of lean NO{sub x} trap aging, and to understand the effect of washcoat composition on catalyst aging characteristics. The approach utilized involved detailed characterization of model catalysts prior to and after aging, in tandem with measurement of catalyst performance in NO{sub x} storage and reduction. In this manner, NO{sub x} storage and reduction characteristics were correlated with the evolution of catalyst physico-chemical properties upon aging. Rather than using poorly characterized proprietary catalysts, or simple model catalysts of the Pt/BaO/Al{sub 2}O{sub 3} type (representing the first generation of LNTs), Pt/Rh/BaO/Al{sub 2}O{sub 3} catalysts were employed which also incorporated CeO{sub 2} or CeO{sub 2}-ZrO{sub 2}, representing a model system which more accurately reflects current LNT formulations. Catalysts were prepared in which the concentration of each of the main components was systematically varied: Pt (50, 75 or 100 g/ft{sup 3}), Rh (10 or 20 g/ft{sup 3}), BaO (15, 30 or 45 g/L), and either CeO{sub 2} (0, 50 or 100 g/L) or CeO{sub 2}-ZrO{sub 2} (0, 50 or 100 g/L). A high surface area La-stabilized alumina was used to support the BaO phase. Catalysts were obtained by washcoating onto standard cordierite substrates, the total washcoat loading being set at 260 g/L. La-stabilized alumina was used as the balance. Subsequent to de-greening, the NO{sub x} storage and reduction characteristics of the catalysts were evaluated on a bench reactor, after which the catalysts were aged on a bench reactor to the equivalent of ca. 75,000 miles of road aging using a published accelerated aging protocol. The aged catalysts were then subjected to the same evaluation proecdure used for the de-greened catalysts. In addition to the use of standard physico-chemical analytical techniques for studying the fresh and aged model catalysts, use was made of advanced analytical tools for characterizing their NO{sub x} storage/reduction and sulfation/desulfation characteristics, such as Spatially resolved capillary-inlet Mass Spectrometry (SpaciMS) and in situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS).

  12. AGING PERFORMANCE OF MODEL 9975 PACKAGE FLUOROELASTOMER O-RINGS

    SciTech Connect (OSTI)

    Hoffman, E.; Daugherty, W.; Skidmore, E.; Dunn, K.; Fisher, D.

    2011-05-31

    The influence of temperature and radiation on Viton{reg_sign} GLT and GLT-S fluoroelastomer O-rings is an ongoing research focus at the Savannah River National Laboratory. The O-rings are credited for leaktight containment in the Model 9975 shipping package used for transportation of plutonium-bearing materials. At the Savannah River Site, the Model 9975 packages are being used for interim storage. Primary research efforts have focused on surveillance of O-rings from actual packages, leak testing of seals at bounding aging conditions and the effect of aging temperature on compression stress relaxation behavior, with the goal of service life prediction for long-term storage conditions. Recently, an additional effort to evaluate the effect of aging temperature on the oxidation of the materials has begun. Degradation in the mechanical properties of elastomers is directly related to the oxidation of the polymer. Sensitive measurements of the oxidation rate can be performed in a more timely manner than waiting for a measurable change in mechanical properties, especially at service temperatures. Measuring the oxidation rate therefore provides a means to validate the assumption that the degradation mechanisms(s) do not change from the elevated temperatures used for accelerated aging and the lower service temperatures. Monitoring the amount of oxygen uptake by the material over time at various temperatures can provide increased confidence in lifetime predictions. Preliminary oxygen consumption analysis of a Viton GLT-based fluoroelastomer compound (Parker V0835-75) using an Oxzilla II differential oxygen analyzer in the temperature range of 40-120 C was performed. Early data suggests oxygen consumption rates may level off within the first 100,000 hours (10-12 years) at 40 C and that sharp changes in the degradation mechanism (stress-relaxation) are not expected over the temperature range examined. This is consistent with the known long-term heat aging resistance of fluoroelastomers relative to hydrocarbon-based elastomers, and in absence of antioxidants that may be consumed over time. Additional experimental effort will be undertaken in the short term range within the first 100 hours of thermal aging to capture further details of the oxygen consumption rate.

  13. PETN: Variation in Physical and Chemical Characteristics Related to Aging.

    SciTech Connect (OSTI)

    Monroe, D. C.; Laintz, K. E.; Kramer, J. F.; Peterson, P. D.

    2006-01-01

    Physical and chemical analyses of five PETN (pentaerythritol tetranitrate) batches have been conducted to assist in defining powder acceptance criteria for qualification of newly manufactured powders, as well as for examination of potential changes related to aging and thus changes in performance. Results showed that (1) repeatable Fisher Sub-Sieve Sizer measurements (which relate well to historic performance data) could be obtained with consistent sample setup and measurement techniques; (2) BET nitrogen adsorption estimates of surface area correlate well with Fisher measurements and appear less variable; (3) PharmaVision particle size analyses show promise in discriminating among PETN batches; and (4) SEMs are extremely useful in semi-quantitative discrimination among batches. Physical and chemical data will be related to performance data (to be obtained) to develop quantitative physical and chemical tests useful in predicting performance over time, i.e., as powders age.

  14. Manhattan Project: Postscript--The Nuclear Age, 1945-Present

    Office of Scientific and Technical Information (OSTI)

    Government-suggested fallout shelter design, 1950s POSTSCRIPT--THE NUCLEAR AGE (1945-Present) Events Informing the Public, August 1945 The Manhattan Engineer District, 1945-1946 First Steps toward International Control, 1944-1945 Search for a Policy on International Control, 1945 Negotiating International Control, 1945-1946 Civilian Control of Atomic Energy, 1945-1946 Operation Crossroads, July 1946 The VENONA Intercepts, 1946-1980 The Cold War, 1945-1990 Nuclear Proliferation, 1949-present Joe

  15. Materials Compatibility and Aging for Flux and Cleaner Combinations.

    SciTech Connect (OSTI)

    Archuleta, Kim; Piatt, Rochelle

    2015-01-01

    A materials study of high reliability electronics cleaning is presented here. In Phase 1, mixed type substrates underwent a condensed contaminants application to view a worst- case scenario for unremoved flux with cleaning agent residue for parts in a silicone oil filled environment. In Phase 2, fluxes applied to copper coupons and to printed wiring boards underwent gentle cleaning then accelerated aging in air at 65% humidity and 30 O C. Both sets were aged for 4 weeks. Contaminants were no-clean (ORL0), water soluble (ORH1 liquid and ORH0 paste), and rosin (RMA; ROL0) fluxes. Defluxing agents were water, solvents, and engineered aqueous defluxers. In the first phase, coupons had flux applied and heated, then were placed in vials of oil with a small amount of cleaning agent and additional coupons. In the second phase, pairs of copper coupons and PWB were hand soldered by application of each flux, using tin-lead solder in a strip across the coupon or a set of test components on the PWB. One of each pair was cleaned in each cleaning agent, the first with a typical clean, and the second with a brief clean. Ionic contamination residue was measured before accelerated aging. After aging, substrates were removed and a visual record of coupon damage made, from which a subjective rank was applied for comparison between the various flux and defluxer combinations; more corrosion equated to higher rank. The ORH1 water soluble flux resulted in the highest ranking in both phases, the RMA flux the least. For the first phase, in which flux and defluxer remained on coupons, the aqueous defluxers led to worse corrosion. The vapor phase cleaning agents resulted in the highest ranking in the second phase, in which there was no physical cleaning. Further study of cleaning and rinsing parameters will be required.

  16. Accelerated Aging of Roofing Materials | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Materials Accelerated Aging of Roofing Materials 1 of 2 Berkeley Lab Heat Island Group chemist Mohamad Sleiman prepares to insert clean and soiled roofing specimens into a weatherometer. The weatherometer simulates exposure to heat, moisture, and UV radiation. Image: Heat Island Group, Lawrence Berkeley National Laboratory 2 of 2 Berkeley Lab Heat Island Group chemist Mohamad Sleiman configures a weatherometer to simulate the effects of heat, moisture, and UV radiation on roofing materials.

  17. Deactivation mechanisms of NOx storage materials arising from thermal aging

    Broader source: Energy.gov (indexed) [DOE]

    and sulfur poisoning | Department of Energy Presents the reliationship between Pt particle size and NOx storage performance over model catalysts. Novel reaction protocol designed to decouple effects of thermal deactivation and incomplete desulfation. PDF icon deer08_muntean.pdf More Documents & Publications Mechanisms of Sulfur Poisoning of NOx Adsorber (LNT) Materials Investigation of Aging Mechanisms in Lean NOx Traps CLEERS Coordination & Development of Catalyst Process Kinetic

  18. Report on aging of nuclear power plant reinforced concrete structures

    SciTech Connect (OSTI)

    Naus, D.J.; Oland, C.B.; Ellingwood, B.R.

    1996-03-01

    The Structural Aging Program provides the US Nuclear Regulatory Commission with potential structural safety issues and acceptance criteria for use in continued service assessments of nuclear power plant safety-related concrete structures. The program was organized under four task areas: Program Management, Materials Property Data Base, Structural Component Assessment/Repair Technology, and Quantitative Methodology for Continued Service Determinations. Under these tasks, over 90 papers and reports were prepared addressing pertinent aspects associated with aging management of nuclear power plant reinforced concrete structures. Contained in this report is a summary of program results in the form of information related to longevity of nuclear power plant reinforced concrete structures, a Structural Materials Information Center presenting data and information on the time variation of concrete materials under the influence of environmental stressors and aging factors, in-service inspection and condition assessments techniques, repair materials and methods, evaluation of nuclear power plant reinforced concrete structures, and a reliability-based methodology for current and future condition assessments. Recommendations for future activities are also provided. 308 refs., 61 figs., 50 tabs.

  19. 2012 ACCOMPLISHMENTS - TRITIUM AGING STUDIES ON STAINLESS STEELS

    SciTech Connect (OSTI)

    Morgan, M.

    2013-01-31

    This report summarizes the research and development accomplishments during FY12 for the tritium effects on materials program. The tritium effects on materials program is designed to measure the long-term effects of tritium and its radioactive decay product, helium-3, on the structural properties of forged stainless steels which are used as the materials of construction for tritium reservoirs. The FY12 R&D accomplishments include: (1) Fabricated and Thermally-Charged 150 Forged Stainless Steel Samples with Tritium for Future Aging Studies; (2) Developed an Experimental Plan for Measuring Cracking Thresholds of Tritium-Charged-and-Aged Steels in High Pressure Hydrogen Gas; (3) Calculated Sample Tritium Contents For Laboratory Inventory Requirements and Environmental Release Estimates; (4) Published report on Cracking Thresholds and Fracture Toughness Properties of Tritium-Charged-and-Aged Stainless Steels; and, (5) Published report on The Effects of Hydrogen, Tritium, and Heat Treatment on the Deformation and Fracture Toughness Properties of Stainless Steels. These accomplishments are highlighted here and references given to additional reports for more detailed information.

  20. AGING AND IODINE LOADING OF SILVER-FUNCTIONALIZED AEROGELS

    SciTech Connect (OSTI)

    Bruffey, Stephanie H [ORNL; Jubin, Robert Thomas [ORNL; Anderson, Kaara K [ORNL; Walker Jr, Joseph Franklin [ORNL

    2013-01-01

    Engineered silver-functionalized silica aerogels are being investigated for their application in off-gas treatment at a used nuclear fuel reprocessing facility. Reprocessing will release several key volatile radionuclides, including iodine-129. To achieve regulatory compliance, iodine-129 must be removed from any off-gas stream prior to environmental discharge. Silver-functionalized aerogels have been demonstrated to have high iodine capture capacity, high porosity and potential for conversion into a waste form. Capture materials used in off-gas treatment may be exposed to a heated, high humidity, acidic gas stream for months. Extended exposure to this stream could affect sorbent performance. It was the aim of this study to evaluate what impacts might be observed when Ag0-functionalized aerogels prepared at Pacific Northwest National Laboratory were contacted with a dry air stream for up to 6 months and then used to adsorb iodine from a synthetic off-gas stream. Results demonstrate that there is some loss of iodine capture capacity caused by aging, but that this loss is not as marked as for aging of more traditional iodine sorbents, such as silver-impregnated mordenite. Specifically, aging silver-functionalized aerogel under a dry air stream for up to 6 months can decrease its iodine capacity from 41wt% to 32wt%.

  1. Aging and iodine loading of silver-functionalized aerogels

    SciTech Connect (OSTI)

    Bruffey, S.H.; Jubin, R.T.; Anderson, K.K.; Walker, J.F. [Oak Ridge National Laboratory, P.O. Box 2008, MS-6223, Oak Ridge, TN 37831 (United States)

    2013-07-01

    Engineered silver-functionalized silica aerogels are being investigated for their potential application in off-gas treatment at a used nuclear fuel reprocessing facility. Reprocessing will release several key volatile radionuclides, including iodine-129. To achieve regulatory compliance, iodine-129 must be removed from any off-gas stream prior to environmental discharge. Ag{sup 0}-functionalized aerogels have been demonstrated to have high iodine-capture capacity, high porosity, and potential for conversion into a waste form. Capture materials used in off-gas treatment may be exposed to a heated, high-humidity, acidic gas stream for months. Extended exposure to this stream could affect sorbent performance. It was the aim of this study to evaluate what impacts might be observed when Ag{sup 0}-functionalized aerogels prepared at Pacific Northwest National Laboratory were contacted with a dry air stream for up to 6 months and then used to adsorb iodine from a synthetic off-gas stream. Results demonstrate that there is some loss of iodine-capture capacity caused by aging, but that this loss is not as marked as for aging of more traditional iodine sorbents, such as silver-impregnated mordenite. Specifically, aging silver-functionalized aerogel under a dry air stream for up to 6 months can decrease its iodine capacity from 41 wt% to 32 wt%. (authors)

  2. Performance of bolted closure joint elastomers under cask aging conditions

    SciTech Connect (OSTI)

    Verst, C.; Sindelar, R.; Skidmore, E.; Daugherty, W.

    2015-07-23

    The bolted closure joint of a bare spent fuel cask is susceptible to age-related degradation and potential loss of confinement function under long-term storage conditions. Elastomeric seals, a component of the joint typically used to facilitate leak testing of the primary seal that includes the metallic seal and bolting, is susceptible to degradation over time by several mechanisms, principally via thermo-oxidation, stress-relaxation, and radiolytic degradation under time and temperature condition. Irradiation and thermal exposure testing and evaluation of an ethylene-propylene diene monomer (EPDM) elastomeric seal material similar to that used in the CASTOR® V/21 cask for a matrix of temperature and radiation exposure conditions relevant to the cask extended storage conditions, and development of semiempirical predictive models for loss of sealing force is in progress. A special insert was developed to allow Compressive Stress Relaxation (CSR) measurements before and after the irradiation and/or thermal exposure without unloading the elastomer. A condition of the loss of sealing force for the onset of leakage was suggested. The experimentation and modeling being performed could enable acquisition of extensive coupled aging data as well as an estimation of the timeframe when loss of sealing function under aging (temperature/radiation) conditions may occur.

  3. Boiling-Water Reactor internals aging degradation study. Phase 1

    SciTech Connect (OSTI)

    Luk, K.H.

    1993-09-01

    This report documents the results of an aging assessment study for boiling water reactor (BWR) internals. Major stressors for BWR internals are related to unsteady hydrodynamic forces generated by the primary coolant flow in the reactor vessel. Welding and cold-working, dissolved oxygen and impurities in the coolant, applied loads and exposures to fast neutron fluxes are other important stressors. Based on results of a component failure information survey, stress corrosion cracking (SCC) and fatigue are identified as the two major aging-related degradation mechanisms for BWR internals. Significant reported failures include SCC in jet-pump holddown beams, in-core neutron flux monitor dry tubes and core spray spargers. Fatigue failures were detected in feedwater spargers. The implementation of a plant Hydrogen Water Chemistry (HWC) program is considered as a promising method for controlling SCC problems in BWR. More operating data are needed to evaluate its effectiveness for internal components. Long-term fast neutron irradiation effects and high-cycle fatigue in a corrosive environment are uncertainty factors in the aging assessment process. BWR internals are examined by visual inspections and the method is access limited. The presence of a large water gap and an absence of ex-core neutron flux monitors may handicap the use of advanced inspection methods, such as neutron noise vibration measurements, for BWR.

  4. Pressurized-water reactor internals aging degradation study. Phase 1

    SciTech Connect (OSTI)

    Luk, K.H.

    1993-09-01

    This report documents the results of a Phase I study on the effects of aging degradations on pr internals. Primary stressers for internals an generated by the primary coolant flow in the they include unsteady hydrodynamic forces and pump-generated pressure pulsations. Other stressors are applied loads, manufacturing processes, impurities in the coolant and exposures to fast neutron fluxes. A survey of reported aging-related failure information indicates that fatigue, stress corrosion cracking (SCC) and mechanical wear are the three major aging-related degradation mechanisms for PWR internals. Significant reported failures include thermal shield flow-induced vibration problems, SCC in guide tube support pins and core support structure bolts, fatigue-induced core baffle water-jet impingement problems and excess wear in flux thimbles. Many of the reported problems have been resolved by accepted engineering practices. Uncertainties remain in the assessment of long-term neutron irradiation effects and environmental factors in high-cycle fatigue failures. Reactor internals are examined by visual inspections and the technique is access limited. Improved inspection methods, especially one with an early failure detection capability, can enhance the safety and efficiency of reactor operations.

  5. Aging of Iodine-Loaded Silver Mordenite in NO2

    SciTech Connect (OSTI)

    Bruffey, Stephanie H.; Jubin, Robert Thomas; Patton, Kaara K.; Walker Jr, Joseph Franklin

    2014-04-01

    Used nuclear fuel facilities need to control and minimize radioactive emissions. Off-gas systems are designed to remove radioactive contaminants, such as 85Kr, 14C, 3H, and 129I. In an off-gas system, any capture material will be exposed to a gas stream for months at a time. This gas stream may be at elevated temperature and could contain water, NOx gas, or a variety of other constituents comprising the dissolver off-gas stream in a nuclear fuel reprocessing plant. For this reason, it is important to evaluate the effects of long-term exposure, or aging, on proposed capture materials. One material under consideration is reduced silver mordenite (Ag0Z), which is recognized for its efficient iodine capture properties. Iodine is immobilized on Ag0Z as AgI, a solid with low volatility (m.p. ? 500C). The aim of this study was to determine whether extended aging at elevated temperature in a nominally 2% NO2 environment would result in a loss of immobilized iodine from this material due to either physical or chemical changes that might occur during aging. Charges of iodine-loaded reduced silver mordenite (I2-Ag0Z) were exposed to a 2% NO2 environment for 1, 2, 3, and 4 months at 150C, then analyzed for iodine losses The aging study was completed successfully. The material did not visibly change color or form. The results demonstrate that no significant iodine loss was observed over the course of 4 months of 2% NO2 aging of I2-Ag0Z at elevated temperature within the margin of error and the variability (~10%) in the loading along the beds. This provides assurance that iodine will remain immobilized on Ag0Z during extended online use in an off-gas capture treatment system. Future tests should expose I2-Ag0Z to progressively more complex feed gases in an effort to accurately replicate the conditions expected in a reprocessing facility.

  6. New Technologies for Repairing Aging Cables in Nuclear Power Plants

    SciTech Connect (OSTI)

    Simmons, Kevin L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fifield, Leonard S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Westman, Matthew P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-09-11

    The goal of this project is to demonstrate a proof-of-concept for a technique to repair aging cables that have been subjected to degradation associated with long-term thermal and radiation exposure in nuclear power plants. The physical degradation of the aging cables manifests itself primarily as cracking and increased brittleness of the polymeric electrical insulation. Therefore, the proposed cable-repair concept comprises development of techniques to impart a softening agent within the deteriorated polymer insulation jacket so as to regain the ability of the insulation to stretch without failing and possibly to heal existing cracks in the insulation. Our approach is to use commercially available ethylene-propylene rubber (EPR) as the relevant test material, demonstrate the adsorption of chemical treatments in the EPR and quantify changes in resulting physical and mechanical properties. EPR cable samples have been thermally treated in air to produce specimens corresponding to the full range of cable age-performance points from new (>350% elongation at break) to end-of-life (<50% elongation at break). The current focus is on two chemical treatments selected as candidates for restoring age-related cable elasticity loss: a rubber plasticizer and a reactive silane molecule. EPR specimens of 200, 150, 100, and 50% elongation at break have been soaked in the candidate chemical treatments and the kinetics of chemical uptake, measured by change in mass of the samples, has been determined. Mechanical properties as a function of aging and chemical treatment have been measured including ultimate tensile strength, tensile modulus at 50% strain, elongation at break, and storage modulus. Dimensional changes with treatment and changes in glass transition temperature were also investigated. These ongoing experiments are expected to provide insight into the physical-chemical nature of the effect of thermal degradation on EPR rejuvenation limits and to advance novel methods for restoring the ability of degraded EPR to be compliant and resist fracture. The results of this research reveal that absorption of chemical treatments can lower the glass transition temperature and modulus of EPR. Chemical treatments pursued thus far have proven ineffective at restoring EPR strength and elongation at break. Future work will combine the plasticizer modalities found to successfully increase the volume of the EPR, reduce EPR glass transition temperature and reduce EPR modulus with promising chemistries that will repair the damage of the polymer, potentially using the plasticizer as a host for the new chemistry.

  7. Aging assessment of essential HVAC chillers used in nuclear power plants. Phase 1, Volume 1

    SciTech Connect (OSTI)

    Blahnik, D.E.; Klein, R.F.

    1993-09-01

    The Pacific Northwest Laboratory conducted a Phase I aging assessment of chillers used in the essential safety air-conditioning systems of nuclear power plants. Centrifugal chillers in the 75- to 750-ton refrigeration capacity range are the predominant type used. The chillers used, and air-conditioning systems served, vary in design from plant-to-plant. It is crucial to keep chiller internals very clean and to prevent the leakage of water, air, and other contaminants into the refrigerant containment system. Periodic operation on a weekly or monthly basis is necessary to remove moisture and noncondensable gases that gradually build up inside the chiller. This is especially desirable if a chiller is required to operate only as an emergency standby unit. The primary stressors and aging mechanisms that affect chillers include vibration, excessive temperatures and pressures, thermal cycling, chemical attack, and poor quality cooling water. Aging is accelerated by moisture, non-condensable gases (e.g., air), dirt, and other contamination within the refrigerant containment system, excessive start/stop cycling, and operating below the rated capacity. Aging is also accelerated by corrosion and fouling of the condenser and evaporator tubes. The principal cause of chiller failures is lack of adequate monitoring. Lack of performing scheduled maintenance and human errors also contribute to failures.

  8. Accelerated aging of GaAs concentrator solar cells

    SciTech Connect (OSTI)

    Gregory, P.E.

    1982-04-01

    An accelerated aging study of AlGaAs/GaAs solar cells has been completed. The purpose of the study was to identify the possible degradation mechanisms of AlGaAs/GaAs solar cells in terrestrial applications. Thermal storage tests and accelerated AlGaAs corrosion studies were performed to provide an experimental basis for a statistical analysis of the estimated lifetime. Results of this study suggest that a properly designed and fabricated AlGaAs/GaAs solar cell can be mechanically rugged and environmentally stable with projected lifetimes exceeding 100 years.

  9. Tank waste chemistry: A new understanding of waste aging

    SciTech Connect (OSTI)

    Babad, H.; Camaioni, D.M.; Lilga, M.A.; Samuels, W.D.; Strachan, D.M.

    1993-02-01

    There is concern about the risk of uncontrolled exothermic reaction(s) in Hanford Site waste tanks containing NO{sub 3}{sup {minus}}/NO{sub 2} based salts and/or metal hydroxide sludges in combination with organics or ferrocyanides. However, gradual oxidation of the waste in the tanks to less reactive species appears to have reduced the risk. In addition, wastes sampled to date contain sufficiently large quantities of water so that propagation reactions are highly unlikely. This paper investigates various aspects of the aging of Hanford tank wastes.

  10. Estimating the age of alleles by use of intraallelic variability

    SciTech Connect (OSTI)

    Slatkin, M.; Rannala, B.

    1997-02-01

    A method is presented for estimating the age of an allele by use of its frequency and the extent of variation among different copies. The method uses the joint distribution of the number of copies in a population sample and the coalescence times of the intraallelic gene genealogy conditioned on the number of copies. The linear birth-death process is used to approximate the dynamics of a rare allele in a finite population. A maximum-likelihood estimate of the age of the allele is obtained by Monte Carlo integration over the coalescence times. The method is applied to two alleles at the cystic fibrosis (CFTR) locus, {Delta}F508 and G542X, for which intraallelic variability at three intronic microsatellite loci has been examined. Our results indicate that G542X is somewhat older than {Delta}F508. Although absolute estimates depend on the mutation rates at the microsatellite loci, our results support the hypothesis that {Delta}F508 arose <500 generations ({approx}10,000 years) ago. 32 refs., 4 figs.

  11. Aging assessment of surge protective devices in nuclear power plants

    SciTech Connect (OSTI)

    Davis, J.F.; Subudhi, M.; Carroll, D.P.

    1996-01-01

    An assessment was performed to determine the effects of aging on the performance and availability of surge protective devices (SPDs), used in electrical power and control systems in nuclear power plants. Although SPDs have not been classified as safety-related, they are risk-important because they can minimize the initiating event frequencies associated with loss of offsite power and reactor trips. Conversely, their failure due to age might cause some of those initiating events, e.g., through short circuit failure modes, or by allowing deterioration of the safety-related component(s) they are protecting from overvoltages, perhaps preventing a reactor trip, from an open circuit failure mode. From the data evaluated during 1980--1994, it was found that failures of surge arresters and suppressers by short circuits were neither a significant risk nor safety concern, and there were no failures of surge suppressers preventing a reactor trip. Simulations, using the ElectroMagnetic Transients Program (EMTP) were performed to determine the adequacy of high voltage surge arresters.

  12. Helium Nano-Bubble Evolution in Aging Metal Tritides

    SciTech Connect (OSTI)

    Cowgill, Donald F.

    2005-07-15

    A continuum-scale, evolutionary model of bubble nucleation, growth and He release for aging metal tritides is described which accounts for major features of the tritide database. Bubble nucleation, modeled as self-trapping of interstitially diffusing He atoms, occurs during the first few days following tritium introduction into the metal. Bubble growth by dislocation loop punching yields good agreement between He atomic volumes and bubble pressures determined from bulk swelling and {sup 3}He NMR data. The bubble spacing distribution determined from NMR is shown to remain fixed with age, justifying the separation of nucleation and growth phases and providing a sensitive test of the growth formulation. Late in life, bubble interactions are proposed to produce cooperative stress effects, which lower the bubble pressure. Helium generated near surfaces and surface-connected porosity accounts for the low-level early helium release. Use of an average ligament stress criterion predicts an onset of inter-bubble fracture in good agreement with the He/Metal ratio observed for rapid He release. From the model, it is concluded that He retention can be controlled through control of bubble nucleation.

  13. NMR studies of aging effects in palladium tritide

    SciTech Connect (OSTI)

    Abell, G.C.; Attalla, A.

    1988-09-01

    This paper presents Nuclear Magnetic Resonance (NMR) studies of aging phenomena in palladium tritide. /sup 3/He NMR relaxation parameters have been measured as a function of temperature for 6-, 13-, and 22-month-old beta phase palladium tritide. The most significant result of this study is the observation of a solid/fluid phase transition near 250 K of /sup 3/He that has accumulated in the PdT/sub x/ substrate via triton decay. Although the existence of solid helium at relatively high temperatures had been predicted for helium in metals, it had not previously been confirmed in any metal/helium system. The observed melting temperatures, together with the known equation of state for /sup 4/He, allow a determination of the helium density as a function of age. The atomic density obtained in this way is approximately 2.0 times that of palladium metal, agreeing with densities inferred from dilatometric measurements of other metal tritides and also with predictions based on the concept of dislocation loop punching by highly overpressurized He bubbles. The /sup 3/He signal in the 22-month-old sample was sufficiently strong to allow a detailed study of melting as a function of temperature, and provides information on the distribution of densities over the ensemble of bubbles.

  14. Structural aging program to assess the adequacy of critical concrete components in nuclear power plants

    SciTech Connect (OSTI)

    Naus, D.J.; Marchbanks, M.F.; Oland, C.B.; Arndt, E.G.

    1989-01-01

    The Structural Aging (SAG) Program is carried out by the Oak Ridge National Laboratory (ORNL) under sponsorship of the United States Nuclear Regulatory Commission (USNRC). The Program has evolved from preliminary studies conducted to evaluate the long-term environmental challenges to light-water reactor safety-related concrete civil structures. An important conclusion of these studies was that a damage methodology, which can provide a quantitative measure of a concrete structure's durability with respect to potential future requirements, needs to be developed. Under the SAG Program, this issue is being addressed through: establishment of a structural materials information center, evaluation of structural component assessment and repair technologies, and development of a quantitative methodology for structural aging determinations. Progress to date of each of these activities is presented as well as future plans. 7 refs., 5 figs.

  15. Age and location of volcanic centers less than or equal to 3...

    Office of Scientific and Technical Information (OSTI)

    age, are shown. Location of the volcanic vents and rocks were taken from Luedke and Smith (1978). Ages were obtained from the original literature in all cases except for McKee...

  16. Age And Nature Of Deposits On The Submarine Flanks Of Piton De...

    Open Energy Info (EERE)

    Age And Nature Of Deposits On The Submarine Flanks Of Piton De La Fournaise (Reunion Island) Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Age...

  17. Developing 226Ra and 227Ac age-dating techniques for nuclear...

    Office of Scientific and Technical Information (OSTI)

    Accepted Manuscript: Developing 226Ra and 227Ac age-dating techniques for nuclear ... Title: Developing 226Ra and 227Ac age-dating techniques for nuclear forensics to gain ...

  18. Fact #715: February 20, 2012 The Average Age of Light Vehicles Continues to Rise

    Broader source: Energy.gov [DOE]

    The average age for cars and light trucks continues to rise as consumers hold onto their vehicles longer. Between 1995 and 2011, the average age for cars increased by 32% from 8.4 years to 11.1...

  19. APBF- DEC Heavy-Duty NOx Adsorber/DPF Project: Catalyst Aging...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    DEC Heavy-Duty NOx AdsorberDPF Project: Catalyst Aging Study APBF- DEC Heavy-Duty NOx AdsorberDPF Project: Catalyst Aging Study 2004 Diesel Engine Emissions Reduction (DEER) ...

  20. Accelerated Thermal Aging of Fe-Zeolite SCR Catalysts Using an...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Thermal Aging of Fe-Zeolite SCR Catalysts Using an Engine-Based Systems Approach Accelerated Thermal Aging of Fe-Zeolite SCR Catalysts Using an Engine-Based Systems Approach This ...

  1. Characterization of Dry-Air Aged Granules of Silver-Functionalized...

    Office of Scientific and Technical Information (OSTI)

    Dry-Air Aged Granules of Silver-Functionalized Silica Aerogel Citation Details In-Document Search Title: Characterization of Dry-Air Aged Granules of Silver-Functionalized Silica ...

  2. Characterization of Dry-Air Aged Granules of Silver-Functionalized...

    Office of Scientific and Technical Information (OSTI)

    Characterization of Dry-Air Aged Granules of Silver-Functionalized Silica Aerogel Citation Details In-Document Search Title: Characterization of Dry-Air Aged Granules of Silver-Fun...

  3. Delamination Failures in Long-Term Field Aged PV Modules from...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Delamination Failures in Long-Term Field Aged PV Modules from Point of View of Encapsulant Delamination Failures in Long-Term Field Aged PV Modules from Point of View of ...

  4. Accelerated aging tests of liners for uranium mill tailings disposal

    SciTech Connect (OSTI)

    Barnes, S.M.; Buelt, J.L.; Hale, V.Q.

    1981-11-01

    This document describes the results of accelerated aging tests to determine the long-term effectiveness of selected impoundment liner materials in a uranium mill tailings environment. The study was sponsored by the US Department of Energy under the Uranium Mill Tailings Remedial Action Project. The study was designed to evaluate the need for, and the performance of, several candidate liners for isolating mill tailings leachate in conformance with proposed Environmental Protection Agency and Nuclear Regulatory Commission requirements. The liners were subjected to conditions known to accelerate the degradation mechanisms of the various liners. Also, a test environment was maintained that modeled the expected conditions at a mill tailings impoundment, including ground subsidence and the weight loading of tailings on the liners. A comparison of installation costs was also performed for the candidate liners. The laboratory testing and cost information prompted the selection of a catalytic airblown asphalt membrane and a sodium bentonite-amended soil for fiscal year 1981 field testing.

  5. Radiation Therapy for Neovascular Age-related Macular Degeneration

    SciTech Connect (OSTI)

    Kishan, Amar U.; Modjtahedi, Bobeck S.; Morse, Lawrence S.; Lee, Percy

    2013-03-01

    In the enormity of the public health burden imposed by age-related macular degeneration (ARMD), much effort has been directed toward identifying effective and efficient treatments. Currently, anti-vascular endothelial growth factor (VEGF) injections have demonstrated considerably efficacy in treating neovascular ARMD, but patients require frequent treatment to fully benefit. Here, we review the rationale and evidence for radiation therapy of ARMD. The results of early photon external beam radiation therapy are included to provide a framework for the sequential discussion of evidence for the usage of stereotactic radiation therapy, proton therapy, and brachytherapy. The evidence suggests that these 3 modern modalities can provide a dose-dependent benefit in the treatment of ARMD. Most importantly, preliminary data suggest that all 3 can be used in conjunction with anti-VEGF therapeutics, thereby reducing the frequency of anti-VEGF injections required to maintain visual acuity.

  6. Electrochemical Aging of Thermal-Sprayed Zinc Anodes on Concrete

    SciTech Connect (OSTI)

    Holcomb, G.R.; Bullard, S.J.; Covino, B.S. Jr.; Cramer, S.D.; Cryer, C.B.; McGill, G.E.

    1996-10-01

    Thermal-sprayed zinc anodes are used in impressed current cathodic protection systems for some of Oregon's coastal reinforced concrete bridges. Electrochemical aging of zinc anodes results in physical and chemical changes at the zinc-concrete interface. Concrete surfaces heated prior to thermal-spraying had initial adhesion strengths 80 pct higher than unheated surfaces. For electrochemical aging greater than 200 kC/m{sup 2} (5.2 A h/ft{sup 2}), there was no difference in adhesion strengths for zinc on preheated and unheated concrete. Adhesion strengths decreased monotonically after about 400 to 600 kC/m{sup 2} (10.4 to 15.6 A-h/ft{sup 2}) as a result of the reaction zones at the zinc-concrete interface. A zone adjacent to the metallic zinc (and originally part of the zinc coating) was primarily zincite (ZnO), with minor constituents of wulfingite (Zn(OH){sub 2}), simonkolleite (Zn{sub 5}(OH) {sub 8}C{sub l2}{sup .}H{sub 2}O), and hydrated zinc hydroxide sulfates (Zn{sub 4}SO{sub 4}(OH){sub 6}{sup .}xH{sub 2}O). This zone is the locus for cohesive fracture when the zinc coating separates from the concrete during adhesion tests. Zinc ions substitute for calcium in the cement paste adjacent to the coating as the result of secondary mineralization. The initial estimate of the coating service life based on adhesion strength measurements in accelerated impressed current cathodic protection tests is about 27 years.

  7. The effect of chrome adhesion layer on quartz resonator aging. (Technical

    Office of Scientific and Technical Information (OSTI)

    Report) | SciTech Connect Technical Report: The effect of chrome adhesion layer on quartz resonator aging. Citation Details In-Document Search Title: The effect of chrome adhesion layer on quartz resonator aging. This SAND report documents a late start LDRD designed to determine the possible aging effects of a quartz resonator gold adhesion layer. Sandia uses quartz resonators for applications. These applications require a very stable frequency source with excellent aging (low drift)

  8. Aging Impacts Transcriptome but not Genome of Hormone-dependentBreast Cancers

    SciTech Connect (OSTI)

    Yau, Christina; Fedele, Vita; Roydasgupta, Ritu; Fridlyand, Jane; Hubbard, Alan; Gray, Joe W.; Chew, Karen; Dairkee, Shanaz H.; Moore, DanH.; Schittulli, Francesco; Tommasi, Stefania; Paradiso, Angelo; Albertson, Donna G.; Benz, Christopher C.

    2007-10-09

    Age is one of the most important risk factors for human malignancies, including breast cancer; in addition, age-at-diagnosis has been shown to be an independent indicator of breast cancer prognosis. However, except for inherited forms of breast cancer, there is little genetic or epigenetic understanding of the biological basis linking aging with sporadic breast cancer incidence and its clinical behavior.

  9. Accelerated Thermal Aging of Fe-Zeolite SCR Catalysts Using an Engine-Based

    Broader source: Energy.gov (indexed) [DOE]

    Systems Approach | Department of Energy This research points the way for developing a rapid aging cycle for SSCR-DPF systems. PDF icon deer08_bunting.pdf More Documents & Publications Deactivation of Accelerated Engine-Aged and Field-Aged SCR Catalysts and the Role of the DOC Catalyst Characterization Non-Petroleum-Based Fuels: Effects on Emissions Control Technologies

  10. Fuel age impacts on gaseous fission product capture during separations

    SciTech Connect (OSTI)

    Jubin, Robert T.; Soelberg, Nicolas R.; Strachan, Denis M.; Ilas, G.

    2012-09-21

    As a result of fuel reprocessing, volatile radionuclides will be released from the facility stack if no processes are put in place to remove them. The radionuclides that are of concern in this document are 3H, 14C, 85Kr, and 129 Rosnick 2007 I. The question we attempt to answer is how efficient must this removal process be for each of these radionuclides? To answer this question, we examine the three regulations that may impact the degree to which these radionuclides must be reduced before process gases can be released from the facility. These regulations are 40 CFR 61 (EPA 2010a), 40 CFR 190(EPA 2010b), and 10 CFR 20 (NRC 2012), and they apply to the total radonuclide release and to the dose to a particular organ – the thyroid. Because these doses can be divided amongst all the radionuclides in different ways and even within the four radionuclides in question, several cases are studied. These cases consider for the four analyzed radionuclides inventories produced for three fuel types—pressurized water reactor uranium oxide (PWR UOX), pressurized water reactor mixed oxide (PWR MOX), and advanced high-temperature gascooled reactor (AHTGR)—several burnup values and time out of reactor extending to 200 y. Doses to the maximum exposed individual (MEI) are calculated with the EPA code CAP-88 ( , 1992). Two dose cases are considered. The first case, perhaps unrealistic, assumes that all of the allowable dose is assigned to the volatile radionuclides. In lieu of this, for the second case a value of 10% of the allowable dose is arbitrarily selected to be assigned to the volatile radionuclides. The required decontamination factors (DFs) are calculated for both of these cases, including the case for the thyroid dose for which 14C and 129I are the main contributors. However, for completeness, for one fuel type and burnup, additional cases are provided, allowing 25% and 50% of the allowable dose to be assigned to the volatile radionuclides. Because 3H and 85Kr have relatively short half-lives, 12.3 y and 10.7 y, respectively, the dose decreases with the time from when the fuel is removed from the reactor to the time it is processed (herein “fuel age”). One possible strategy for limiting the discharges of these short halflife radionuclides is to allow the fuel to age to take advantage of radioactive decay. Therefore, the doses and required DFs are calculated as a function of fuel age. Here we calculate, given the above constraints and assumptions, the minimum ages for each fuel type that would not require additional effluent controls for the shorter half-life volatile radionuclides based on dose considerations. With respect to 129I doses, we find that the highest dose is calculated with iodine as a fine particulate. The dose scales as the fraction of the total 129I that is particulate. Therefore, we assume for all of our calculations that 100% of the 129I is particulate and allow the user of the results given here to scale our calculated doses to their needs. To summarize the data given in the body and appendices of this report, we find that the principal isotopes of concern are 3H and 129I, the latter requiring the highest DFs. The maximum DF value for 129I is 8000 for the illustrated cases. The required DF for 3H could be as high as 720, depending on the age of the fuel processed. The DF for 85Kr could be up to ~60, depending on fuel age. The DF for 14C is in many cases 1 (no treatment required) but could be as high as 30. The DFs required are within the range of DFs that are reported for the capture technologies that are available for the volatile radionuclides. Achieving the required 129I and 3H DFs is more challenging. Variations in stack design and other design factors may also significantly impact the DF requirements.

  11. A review of lunar chronology revealing a preponderance of 4.34-4.37 Ga ages

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Borg, Lars E.; Gaffney, Amy M.; Shearer, Charles K.

    2014-11-24

    In this study, data obtained from Sm-Nd and Rb-Sr isotopic measurements of lunar highlands’ samples are renormalized to common standard values and then used to define ages with a common isochron regression algorithm. The reliability of these ages is evaluated using five criteria that include whether: (1) the ages are defined by multiple isotopic systems, (2) the data demonstrate limited scatter outside uncertainty, (3) initial isotopic compositions are consistent with the petrogenesis of the samples, (4) the ages are defined by an isotopic system that is resistant to disturbance by impact metamorphism, and (5) the rare-earth element abundances determined bymore » isotope dilution of bulk of mineral fractions match those measured by in situ analyses. From this analysis, it is apparent that the oldest highlands’ rock ages are some of the least reliable, and that there is little support for crustal ages older than ~4.40 Ga. A model age for ur-KREEP formation calculated using the most reliable Mg-suite Sm-Nd isotopic systematics, in conjunction with Sm-Nd analyses of KREEP basalts, is 4389 ± 45 Ma. This age is a good match to the Lu-Hf model age of 4353 ± 37 Ma determined using a subset of this sample suite, the average model age of 4353 ± 25 Ma determined on mare basalts with the 146Sm-142Nd isotopic system, with a peak in Pb-Pb ages observed in lunar zircons of ~4340 ± 20 Ma, and the oldest terrestrial zircon age of 4374 ± 6 Ma. The preponderance of ages between 4.34 and 4.37 Ga reflect either primordial solidification of a lunar magma ocean or a widespread secondary magmatic event on the lunar nearside. The first scenario is not consistent with the oldest ages reported for lunar zircons, whereas the second scenario does not account for concordance between ages of crustal rocks and mantle reservoirs.« less

  12. A review of lunar chronology revealing a preponderance of 4.34-4.37 Ga ages

    SciTech Connect (OSTI)

    Borg, Lars E.; Gaffney, Amy M.; Shearer, Charles K.

    2014-11-24

    In this study, data obtained from Sm-Nd and Rb-Sr isotopic measurements of lunar highlands’ samples are renormalized to common standard values and then used to define ages with a common isochron regression algorithm. The reliability of these ages is evaluated using five criteria that include whether: (1) the ages are defined by multiple isotopic systems, (2) the data demonstrate limited scatter outside uncertainty, (3) initial isotopic compositions are consistent with the petrogenesis of the samples, (4) the ages are defined by an isotopic system that is resistant to disturbance by impact metamorphism, and (5) the rare-earth element abundances determined by isotope dilution of bulk of mineral fractions match those measured by in situ analyses. From this analysis, it is apparent that the oldest highlands’ rock ages are some of the least reliable, and that there is little support for crustal ages older than ~4.40 Ga. A model age for ur-KREEP formation calculated using the most reliable Mg-suite Sm-Nd isotopic systematics, in conjunction with Sm-Nd analyses of KREEP basalts, is 4389 ± 45 Ma. This age is a good match to the Lu-Hf model age of 4353 ± 37 Ma determined using a subset of this sample suite, the average model age of 4353 ± 25 Ma determined on mare basalts with the 146Sm-142Nd isotopic system, with a peak in Pb-Pb ages observed in lunar zircons of ~4340 ± 20 Ma, and the oldest terrestrial zircon age of 4374 ± 6 Ma. The preponderance of ages between 4.34 and 4.37 Ga reflect either primordial solidification of a lunar magma ocean or a widespread secondary magmatic event on the lunar nearside. The first scenario is not consistent with the oldest ages reported for lunar zircons, whereas the second scenario does not account for concordance between ages of crustal rocks and mantle reservoirs.

  13. MILLISECOND PULSAR AGES: IMPLICATIONS OF BINARY EVOLUTION AND A MAXIMUM SPIN LIMIT

    SciTech Connect (OSTI)

    Kiziltan, Buelent; Thorsett, Stephen E., E-mail: bulent@astro.ucsc.ed [Department of Astronomy and Astrophysics, University of California and UCO/Lick Observatory, Santa Cruz, CA 95064 (United States)

    2010-05-20

    In the absence of constraints from the binary companion or supernova remnant, the standard method for estimating pulsar ages is to infer an age from the rate of spin-down. While the generic spin-down age may give realistic estimates for normal pulsars, it can fail for pulsars with very short periods. Details of the spin-up process during the low-mass X-ray binary (LMXB) phase pose additional constraints on the period (P) and spin-down rates ( P-dot ) that may consequently affect the age estimate. Here, we propose a new recipe to estimate millisecond pulsar (MSP) ages that parametrically incorporates constraints arising from binary evolution and limiting physics. We show that the standard method can be improved by this approach to achieve age estimates closer to the true age while the standard spin-down age may overestimate or underestimate the age of the pulsar by more than a factor of {approx}10 in the millisecond regime. We use this approach to analyze the population on a broader scale. For instance, in order to understand the dominant energy loss mechanism after the onset of radio emission, we test for a range of plausible braking indices. We find that a braking index of n = 3 is consistent with the observed MSP population. We demonstrate the existence and quantify the potential contributions of two main sources of age corruption: the previously known 'age bias' due to secular acceleration and 'age contamination' driven by sub-Eddington progenitor accretion rates. We explicitly show that descendants of LMXBs that have accreted at very low rates ( m-dot << M-dot{sub Edd}) will exhibit ages that appear older than the age of the Galaxy. We further elaborate on this technique, the implications and potential solutions it offers regarding MSP evolution, the underlying age distribution, and the post-accretion energy loss mechanism.

  14. Greenhouse gas emissions from landfill leachate treatment plants: A comparison of young and aged landfill

    SciTech Connect (OSTI)

    Wang, Xiaojun; Jia, Mingsheng; Chen, Xiaohai; Xu, Ying; Lin, Xiangyu; Kao, Chih Ming; Chen, Shaohua

    2014-07-15

    Highlights: • Young and aged leachate works accounted for 89.1% and 10.9% of 33.35 Gg CO{sub 2} yr{sup −1}. • Fresh leachate owned extremely low ORP and high organic matter content. • Strong CH{sub 4} emissions occurred in the fresh leachate ponds, but small in the aged. • N{sub 2}O emissions became dominant in the treatment units of both systems. • 8.45–11.9% of nitrogen was removed as the form of N{sub 2}O under steady-state. - Abstract: With limited assessment, leachate treatment of a specified landfill is considered to be a significant source of greenhouse gas (GHG) emissions. In our study, the cumulative GHG emitted from the storage ponds and process configurations that manage fresh or aged landfill leachate were investigated. Our results showed that strong CH{sub 4} emissions were observed from the fresh leachate storage pond, with the fluxes values (2219–26,489 mg C m{sup −2} h{sup −1}) extremely higher than those of N{sub 2}O (0.028–0.41 mg N m{sup −2} h{sup −1}). In contrast, the emission values for both CH{sub 4} and N{sub 2}O were low for the aged leachate tank. N{sub 2}O emissions became dominant once the leachate entered the treatment plants of both systems, accounting for 8–12% of the removal of N-species gases. Per capita, the N{sub 2}O emission based on both leachate treatment systems was estimated to be 7.99 g N{sub 2}O–N capita{sup −1} yr{sup −1}. An increase of 80% in N{sub 2}O emissions was observed when the bioreactor pH decreased by approximately 1 pH unit. The vast majority of carbon was removed in the form of CO{sub 2}, with a small portion as CH{sub 4} (<0.3%) during both treatment processes. The cumulative GHG emissions for fresh leachate storage ponds, fresh leachate treatment system and aged leachate treatment system were 19.10, 10.62 and 3.63 Gg CO{sub 2} eq yr{sup −1}, respectively, for a total that could be transformed to 9.09 kg CO{sub 2} eq capita{sup −1} yr{sup −1}.

  15. Static strain aging behavior of ultra low carbon bake hardening steel

    SciTech Connect (OSTI)

    De, A.K.; Cooman, B.C. de; Vandeputte, S.

    1999-09-10

    A detailed study of static strain aging in ultra low carbon (ULC) steel has not yet been reported. Therefore, the present study was carried out to gain an understanding of the aging kinetics in a ULC steel with a total carbon content of 20 ppm. The influence of dislocation density on the aging process was also taken into account. The kinetics of the aging were determined by means of the measurement of strength properties rather than solute concentration as it was experienced that quantitative estimation of such low amount of carbon during aging course would be too difficult with the existing diagnostic tools.

  16. Helium nano-bubble evolution in aging metal tritides.

    SciTech Connect (OSTI)

    Cowgill, Donald F.

    2004-05-01

    A continuum-scale, evolutionary model of helium (He) nano-bubble nucleation, growth and He release for aging bulk metal tritides is presented which accounts for major features of the experimental database. Bubble nucleation, modeled as self-trapping of interstitially diffusing He atoms, is found to occur during the first few days following tritium introduction into the metal and is sensitive to the He diffusivity and pairing energy. An effective helium diffusivity of 0.3 x 10{sup -16} cm{sup 2}/s at 300 K is required to generate the average bubble density of 5x 1017 bubbles/cm3 observed by transmission electron microscopy (TEM). Early bubble growth by dislocation loop punching with a l/radius bubble pressure dependence produces good agreement with He atomic volumes and bubble pressures determined from swelling data, nuclear magnetic resonance (NMR) measurements, and hydride pressure-composition-temperature (PCT) shifts. The model predicts that later in life neighboring bubble interactions may first lower the loop punching pressure through cooperative stress effects, then raise the pressure by partial blocking of loops. It also accounts for the shape of the bubble spacing distribution obtained from NMR data. This distribution is found to remain fixed with age, justifying the separation of nucleation and growth phases, providing a sensitive test of the growth formulation, and indicating that further significant bubble nucleation does not occur throughout life. Helium generated within the escape depth of surfaces and surface-connected porosity produces the low-level early helium release. Accelerated or rapid release is modeled as inter-bubble fracture using an average ligament stress criterion. Good agreement is found between the predicted onset of fracture and the observed He-metal ratio (HeM) for rapid He release from bulk palladium tritide. An examination of how inter-bubble fracture varies over the bubble spacing distribution shows that the critical Hem will be lower for thin films or small particle material. It is concluded that control of He retention can be accomplished through control of bubble nucleation.

  17. AmeriFlux US-Me4 Metolius-old aged ponderosa pine

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Law, Bev [Oregon State University

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Me4 Metolius-old aged ponderosa pine. Site Description - The site is located on land designated as a Research Natural Area (RNA). The site is very open, with even-aged stands of old-growth trees, young trees and mixed aged stands. The eddy-flux tower footprint was classified as ~ 48% mixed aged, ~27% pure old growth and ~25% young aged stands. The data in this workbook describes the mixed aged component. A separate workbook describes the pure old growth component. Law et al (2001) Global Change Biology 7, 755-777; Law et al (2001) Agricultural and Forest Meteorology 110, 27-43; Anthoni et al (2002) Agricultural and Forest Meteorology 111, 203-222; Irvine & Law (2002) Global Change biology 8,1183-1194, Irivne et al (2004) Tree Physiology 24,753-763.

  18. NEW MEMBERS OF THE SCORPIUS-CENTAURUS COMPLEX AND AGES OF ITS SUB-REGIONS

    SciTech Connect (OSTI)

    Song, Inseok; Zuckerman, B.; Bessell, M. S.

    2012-07-15

    We have spectroscopically identified {approx}100 G-, K-, and M-type members of the Scorpius-Centaurus complex. To deduce the age of these young stars we compare their Li {lambda}6708 absorption line strengths against those of stars in the TW Hydrae association and {beta} Pictoris moving group. These line strengths indicate that Sco-Cen stars are younger than {beta} Pic stars whose ages of {approx}12 Myr have previously been derived from a kinematic traceback analysis. Our derived age, {approx}10 Myr, for stars in the Lower Centaurus Crux and Upper Centaurus Lupus subgroups of ScoCen is younger than previously published ages based on the moving cluster method and upper main-sequence fitting. The discrepant ages are likely due to an incorrect (or lack of) cross-calibration between model-dependent and model-independent age-dating methods.

  19. Aging of nuclear station diesel generators: Evaluation of operating and expert experience: Phase 1, Study

    SciTech Connect (OSTI)

    Hoopingarner, K.R.; Vause, J.W.; Dingee, D.A.; Nesbitt, J.F.

    1987-08-01

    Pacific Northwest Laboratory evaluated operational and expert experience pertaining to the aging degradation of diesel generators in nuclear service. The research, sponsored by the US Nuclear Regulatory Commission (NRC), identified and characterized the contribution of aging to emergency diesel generator failures. This report, Volume I, reviews diesel-generator experience to identify the systems and components most subject to aging degradation and isolates the major causes of failure that may affect future operational readiness. Evaluations show that as plants age, the percent of aging-related failures increases and failure modes change. A compilation is presented of recommended corrective actions for the failures identified. This study also includes a review of current, relevant industry programs, research, and standards. Volume II reports the results of an industry-wide workshop held on May 28 and 29, 1986 to discuss the technical issues associated with aging of nuclear service emergency diesel generators.

  20. Confirmation of a late Oligocene-early Miocene age of the Deseadan Salla Beds of Bolivia

    SciTech Connect (OSTI)

    Naeser, C.W.; McKee, E.H.; Johnson, N.M.; MacFadden, B.J.

    1987-11-01

    Three new fission-track (zircon) and four new K-Ar (biotite) dates corroborate a late Oligocene-early Miocene age (22-28 Ma) for the Salla Beds of Bolivia. These ages contrast markedly with the previously accepted age of about 35 Ma for these strata and their contained faunas, and recasts of order and chronology of interchange between New World and Old World mammals.

  1. Ar-40/Ar-39 Age Constraints for the Jaramillo Normal Subchron...

    Open Energy Info (EERE)

    oxygen isotope, climate record calibration of the astronomical timescale proposed by Johnson (1982) and Shackleton et al. (1990). Ar-40Ar-39 ages of a normally magnetized...

  2. Characterization of Dry-Air Aged Granules of Silver-Functionalized...

    Office of Scientific and Technical Information (OSTI)

    Silica Aerogel Matyas, Josef; Fryxell, Glen E.; Robinson, Matthew J. Reprocessing; Silver-functionalized arogel; Radioiodine; Aging; Sorption; BET; SEM; XRD...

  3. Aging effects in palladium and LaNi sub 4. 25 Al sub 0. 75 tritides

    SciTech Connect (OSTI)

    Nobile, A.; Wermer, J.R. ); Walters, R.T. . Plasma Physics Lab.)

    1992-03-01

    Palladium and LaNi{sub 5{minus}x}Al{sub x} (x = 0.30, 0.75, 0.85), which from reversible hydrides, are used for tritium processing and storage in the Savannah River Site (SRS) tritium facilities. As part of a program to develop technology based on the use of reversible metal hydrides for tritium processing and storage, the effects of aging on the thermodynamic behavior of palladium and LaNi{sub 4.25}Al{sub 0.75} tritides are under investigation. During aging, the {sup 3}He tritium decay product remains in the tritide lattice and changes the thermodynamics of the tritium-metal tritide system. Aging effects in 755-day-aged palladium and 1423-day-aged LaNi{sub 4.25}Al{sub 0.75} tritides are reported. Changes in the thermodynamics are determined by measuring tritium desorption isotherms on aging samples. In palladium, aging deceases the desorption isotherm plateau pressure and changes the {alpha}-phase portion of the isotherm. aging-induced changes in desorption isotherms are more drastic in LaNi{sub 4.25}Al{sub 0.75}. Various processes occurring in the tritide lattice which might be responsible for the observed aging effects in palladium and LaNi{sub 4.25}Al{sub 0.75} tritides are discussed in this paper.

  4. Effect of Thermal Aging on NO oxidation and NOx storage in a...

    Broader source: Energy.gov (indexed) [DOE]

    Thermal aging of LNT has numerous material and chemical effects PDF icon deer09toops.pdf More Documents & Publications Impacts of Biodiesel on Emission Control Devices NOx ...

  5. Characterization of Dry-Air Aged Granules of Silver-Functionalized Silica

    Office of Scientific and Technical Information (OSTI)

    Aerogel (Technical Report) | SciTech Connect Dry-Air Aged Granules of Silver-Functionalized Silica Aerogel Citation Details In-Document Search Title: Characterization of Dry-Air Aged Granules of Silver-Functionalized Silica Aerogel This is a letter report to complete level 3 milestone "Assess aging characteristics of silica aerogels" for DOE FCRD program. Recently, samples of Ag0-functionalized silica aerogel were aged in flowing dry air for up to 6 months and then loaded with

  6. Using Pb-210/Ra-226 disequilibria for sablefish, Anoplopoma fimbria, age validation

    SciTech Connect (OSTI)

    Kastelle, C.R.; Kimura, D.K. ); Nevissi, A.E.; Gunderson, D.R. )

    1994-04-01

    Age determination of sablefish (Anoplopoma fimbria) is typically done by counting growth zones on the burnt cross-section of the otolith. The break-and-burn method of age determination is difficult to apply to sablefish. Therefore, we applied a relatively new method of fish age validation, using the disequilibrium of Pb-210/Ra-226 in the otoliths. This method of validation complements previous methods which used oxytetracycline (OTC) marking to validate incremental growth in sablefish otoliths. The Pb-210/Ra-226 disequilibria generally confirmed the ageing criteria used to interpret the otolith's burnt cross-section.

  7. Fuel Cell Catalysts Caught in the Act of Aging | U.S. DOE Office...

    Office of Science (SC) Website

    Fuel Cell Catalysts Caught in the Act of Aging Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic Energy ...

  8. Semi-Annual Report on Work Supporting the International Forum for Reactor Aging Management (IFRAM)

    SciTech Connect (OSTI)

    Bond, Leonard J.; Brenchley, David L.

    2011-11-30

    During the first six months of this project, Pacific Northwest National Laboratory has provided planning and leadership support for the establishment of the International Forum for Reactor Aging Management (IFRAM). This entailed facilitating the efforts of the Global Steering Committee to prepare the charter, operating guidelines, and other documents for IFRAM. It also included making plans for the Inaugural meeting and facilitating its success. This meeting was held on August 4 5, 2011, in Colorado Springs, Colorado. Representatives from Asia, Europe, and the United States met to share information on reactor aging management and to make plans for the future. Professor Tetsuo Shoji was elected chairperson of the Leadership Council. This kick-off event transformed the dream of an international forum into a reality. On August 4-5, 2011, IFRAM began to achieve its mission. The work completed successfully during this period was built upon important previous efforts. This included the development of a proposal for establishing IFRAM and engaging experts in Asia and Europe. The proposal was presented at Engagement workshops in Seoul, Korea (October 2009) and Petten, The Netherlands (May 2010). Participants in both groups demonstrated strong interest in the establishment of IFRAM. Therefore, the Global Steering Committee was formed to plan and carry out the start-up of IFRAM in 2011. This report builds on the initial activities and documents the results of activities over the last six months.

  9. Aging management of fossil-fired plants of Electricite de France: PVP maintenance aspects

    SciTech Connect (OSTI)

    Thoraval, G.

    1995-12-01

    The generation mix of EDF comprises 17,000 MW of fossil-fired units, the ages of which go from 10 to 32 years. Extensive studies have been launched in 1994, inside the Company, to determine: (1) prospects of needs of the grid (domestic/exports); (2) prospects of possible competition in generation field; (3) environmental aspects and possible evolution; (4) adaptation of management of men and organizations; and (5) management of condition of equipment through maintenance policy. This paper focuses on the last item, spotted on pressure vessels and piping. The question is: How to conserve the ``patrimony`` for very long term, with lowest costs to keep it competitive in its very specific role? Several items are examined: (1) the background, the different programs of retrofitting, refurbishment and life extension; (2) conservation during outages, and mothballing procedures and experience; (3) design review, actual design life expectancy; (4) analysis of aging mechanisms through experience feedback; (5) determination of critical components, analysis of their condition, periodical updating; (6) maintenance adaptation, extensive condition-monitored maintenance approach: use of existing probes and data, development of new devices and skills; (7) policy of progressive replacement of worn-out and potentially dangerous components; examples concerning generic problems; (8) management of requirements of pressure vessels regulations; (9) adaptation of spare parts policy; and (10) research and development needed by life management.

  10. Using naturally occurring radionuclides to determine drinking water age in a community water system

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Waples, James T.; Bordewyk, Jason K.; Knesting, Kristina M.; Orlandini, Kent A.

    2015-07-22

    Drinking water quality in a community water system is closely linked to the age of water from initial treatment to time of delivery. However, water age is difficult to measure with conventional chemical tracers; particularly in stagnant water, where the relationship between disinfectant decay, microbial growth, and water age is poorly understood. Using radionuclides that were naturally present in source water, we found that measured activity ratios of 90Y/90Sr and 234Th/238U in discrete drinking water samples of known age accurately estimated water age up to 9 days old (σest: ± 3.8 h, P < 0.0001, r2 = 0.998, n =more » 11) and 25 days old (σest: ± 13.3 h, P < 0.0001, r2 = 0.996, n = 12), respectively. Moreover, 90Y-derived water ages in a community water system (6.8 × 104 m3 d–1 capacity) were generally consistent with water ages derived from an extended period simulation model. Radionuclides differ from conventional chemical tracers in that they are ubiquitous in distribution mains and connected premise plumbing. The ability to measure both water age and an analyte (e.g., chemical or microbe) in any water sample at any time allows for new insight into factors that control drinking water quality.« less

  11. Aging effects in palladium and LaNi sub 4. 25 Al sub 0. 75 tritides

    SciTech Connect (OSTI)

    Nobile, A.; Wermer, J.R.; Walters, R.T.

    1991-01-01

    Palladium and LaNi{sub 5-x}Al{sub x} (x=0.30, 0.75, 0.85), which form reversible hydrides, are used for tritium processing and storage in the Savannah River Site (SRS) tritium facilities. As part of a program to develop technology based on the use of reversible metal hydrides for tritium processing and storage, the effects of aging on the thermodynamic behavior of palladium and LaNi{sub 4.25}Al{sub 0. 75} tritides are under investigation. During aging, the {sup 3}He tritium decay product remains in the tritide lattice and changes the thermodynamics of the tritium-metal tritide system. Aging effects in 755-day-aged palladium and 1423-day-aged LaNi{sub 4.25}Al{sub 0.75} tritides will be reported. Changes in the thermodynamics were determined by measuring tritium desorption isotherms on aging samples. In palladium, aging decreases the desorption isotherm plateau pressure and changes the {alpha}-phase portion of the isotherm. Aging-induced changes in desorption isotherms are more drastic in LaNi{sub 4.25}Al{sub 0.75}. Among the changes noted are: (1) decreased isotherm plateau pressure, (2) increased isotherm plateau slope, and (3) appearance of deep-trapped tritium, removable only by exchange with deuterium.

  12. Nuclear power plant Generic Aging Lessons Learned (GALL). Main report and appendix A

    SciTech Connect (OSTI)

    Kaza, K.E.; Diercks, D.R.; Holland, J.W.; Choi, S.U.

    1996-12-01

    The purpose of this generic aging lessons learned (GALL) review is to provide a systematic review of plant aging information in order to assess materials and component aging issues related to continued operation and license renewal of operating reactors. Literature on mechanical, structural, and thermal-hydraulic components and systems reviewed consisted of 97 Nuclear Plant Aging Research (NPAR) reports, 23 NRC Generic Letters, 154 Information Notices, 29 Licensee Event Reports (LERs), 4 Bulletins, and 9 Nuclear Management and Resources Council Industry Reports (NUMARC IRs) and literature on electrical components and systems reviewed consisted of 66 NPAR reports, 8 NRC Generic Letters, 111 Information Notices, 53 LERs, 1 Bulletin, and 1 NUMARC IR. More than 550 documents were reviewed. The results of these reviews were systematized using a standardized GALL tabular format and standardized definitions of aging-related degradation mechanisms and effects. The tables are included in volume s 1 and 2 of this report. A computerized data base has also been developed for all review tables and can be used to expedite the search for desired information on structures, components, and relevant aging effects. A survey of the GALL tables reveals that all ongoing significant component aging issues are currently being addressed by the regulatory process. However, the aging of what are termed passive components has been highlighted for continued scrutiny. This document is Volume 1, consisting of the executive summary, summary and observations, and an appendix listing the GALL literature review tables.

  13. Proceedings of the Inaugural Meeting of the International Forum for Reactor Aging Management (IFRAM)

    SciTech Connect (OSTI)

    Bond, Leonard J.; Brenchley, David L.

    2011-09-01

    In almost all countries with nuclear power plants (NPPs), regulatory authorities and the nuclear industry are looking at some form of extended operating periods. To support life extension activities it is necessary to ensure the continued safety and reliability of system, structures, and components, and the component materials. Internationally, a variety of individual national and international activities have been initiated including Plant Life Management through the International Atomic Energy Agency, Electric Power Research Institute’s Long Term Operation program, and various national programs in managing materials degradation and related topics. The U.S. Nuclear Regulatory Commission (NRC) engaged the international community in workshops in 2005-2006 to identify research needs and to collect information in an expert panel report on Proactive Management of Materials Degradation (PMMD), which was reported in NUREG/CR-6923. These results are also available via an Information Tool on the internet at http://pmmd.pnl.gov. This information builds on the extensive compilations known as the GALL Report (Generic Aging Lessons Learned, NUREG-1801, Vols. 1 and 2). Pacific Northwest National Laboratory (PNNL) recently issued a report on the review of various international activities in PMMD (PNNL-17779). There have also been initiatives by Electricite de France, Tokyo Electric Power Company, EPRI, and others to establish a "Materials Aging Institute." Within the materials degradation research community there are also networks and technical meetings focused on some elements of PMMD. In spite of all these efforts, there is currently no forum to bring together these diverse activities and provide coordinated information exchange and prioritization of materials aging management/PMMD topics. It is believed that the International Forum for Reactor Aging Management (IFRAM) would be a good way to achieve this goal and help develop new approaches for ensuring continued safe operation in existing and future nuclear power plants. To begin addressing this need, NRC has established a Proactive Management of Materials Degradation Program for managing in-service degradation of metallic components in aging NPPs. The NRC is seeking to facilitate the establishment of IFRAM as a network of international experts who would exchange information on operating experience, best practices, and emerging knowledge. These experts would be willing to work jointly and leverage the separate efforts of existing national programs into a unified approach to enable the potential for the safe and economic life extension of NPPs. A proposal for establishing IFRAM was developed and presented at Engagement workshops in Seoul, Korea (October 2009) and Petten, The Netherlands (May 2010). Participants in both groups demonstrated strong interest in the establishment of IFRAM. Therefore the Global Steering Committee was formed to plan and carry out the start-up of IFRAM in 2011. This group finalized the documents for IFRAM and organized the kick-off meeting. This document records the contents of the inaugural meeting of IFRAM, which was held August 4-5, 2011, at the Cheyenne Mountain Resort in Colorado Springs, Colorado. Representatives from Asia, Europe, and the United States met to share information on reactor aging management and make plans for the future. Professor Tetsuo Shoji was elected chairperson of the Leadership Council. This kick-off event transformed the dream of an international forum into a reality. IFRAM has begun to achieve its mission.

  14. Aging Management Guideline for commercial nuclear power plants: Power and distribution transformers

    SciTech Connect (OSTI)

    Toman, G.; Gazdzinski, R.

    1994-05-01

    This Aging Management Guideline (AMG) provides recommended methods for effective detection and mitigation of age-related degradation mechanisms in power and distribution transformers important to license renewal in commercial nuclear power plants. The intent of this AMG to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR Part 54. This AMG is presented in a manner which allows personnel responsible for performance analysis and maintenance to compare their plant-specific aging mechanisms (expected or already experienced) and aging management program activities to the more generic results and recommendations presented herein.

  15. Aging Management Guideline for commercial nuclear power plants: Motor control centers; Final report

    SciTech Connect (OSTI)

    Toman, G.; Gazdzinski, R.; O`Hearn, E.

    1994-02-01

    This Aging Management Guideline (AMG) provides recommended methods for effective detection and mitigation of age-related degradation mechanisms in Boiling Water Reactor (BWR) and Pressurized Water Reactor (PWR) commercial nuclear power plant motor control centers important to license renewal. The intent of this AMG is to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR Part 54. This AMG is presented in a manner that allows personnel responsible for performance analysis and maintenance to compare their plant-specific aging mechanisms (expected or already experienced) and aging management program activities to the more generic results and recommendations presented herein.

  16. Aging management guideline for commercial nuclear power plants-stationary batteries. Final report

    SciTech Connect (OSTI)

    Berg, R.; Shao, J.; Krencicki, G.; Giachetti, R.

    1994-03-01

    The Aging Management Guideline (AMG) describes recommended methods for effective detection and mitigation of age-related degradation mechanisms in BWR and PWR commercial nuclear power plant stationary batteries important to license renewal. The intent of this AMG is to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR Part 54. This AMG is presented in a manner that allows personnel responsible for performance analysis and maintenance to compare their plant-specific aging mechanisms (expected or already experienced) and aging management program activities to the more generic results and recommendations presented herein.

  17. Aging Management Guideline for commercial nuclear power plants: Electrical switchgear. Final report

    SciTech Connect (OSTI)

    Toman, G.; Gazdzinski, R.; Schuler, K.

    1993-07-01

    This Aging Management Guideline (AMG) provides recommended methods for effective detection and mitigation of age-related degradation mechanisms in BWR and PWR commercial nuclear power plant electrical switchgear important to license renewal. The latent of this AMG to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR Part 54. This AMG is presented in a manner which allows personnel responsible for performance analysis and maintenance, to compare their plant-specific aging mechanisms (expected or already experienced) and aging management program activities to the more generic results and recommendations presented herein.

  18. Aging management guideline for commercial nuclear power plants - tanks and pools

    SciTech Connect (OSTI)

    Blocker, E.; Smith, S.; Philpot, L.; Conley, J.

    1996-02-01

    Continued operation of nuclear power plants for periods that extend beyond their original 40-year license period is a desirable option for many U.S. utilities. U.S. Nuclear Regulatory Commission (NRC) approval of operating license renewals is necessary before continued operation becomes a reality. Effective aging management for plant components is important to reliability and safety, regardless of current plant age or extended life expectations. However, the NRC requires that aging evaluations be performed and the effectiveness of aging management programs be demonstrated for components considered within the scope of license renewal before granting approval for operation beyond 40 years. Both the NRC and the utility want assurance that plant components will be highly reliable during both the current license term and throughout the extended operating period. In addition, effective aging management must be demonstrated to support Maintenance Rule (10 CFR 50.65) activities.

  19. Cross-sectional relationships of exercise and age to adiposity in60,617 male runners

    SciTech Connect (OSTI)

    Williams, Paul T.; Pate, Russell R.

    2004-06-01

    The objective of this report is to assess in men whether exercise affects the estimated age-related increase in adiposity, and contrariwise, whether age affects the estimated exercise-related decrease in adiposity. Cross-sectional analyses of 64,911 male runners who provided data on their body mass index (97.6 percent), waist (91.1 percent), hip (47.1 percent), and chest circumferences (77.9 percent). Between 18 to 55 years old, the decline in BMI with weekly distance run (slope+-SE) was significantly greater in men 25-55 years old (slope+-:-0.036+-0.001 kg/m2 per km/wk) than in younger men (-0.020+-0.002 kg/m 2 per km/wk). Declines in waist circumference with running distance were also significantly greater in older than younger men (P<10-9 for trend),i.e., the slopes decreased progressively from -0.035+-0.004 cm per km/wk in 18-25 year old men to -0.097+-0.003 cm per km/wk in 50-55 year old men. Increases in BMI with age were greater for men who ran under 16km/wk than for longer distance runners. Waist circumference increased with age at all running levels, but the increase appeared to diminish by running further (0.259+-0.015 cm per year if running<8 km/wk and 0.154+-0.003 cm per year for>16 km/wk). In men over 50 years old, BMI declined -0.038+-0.001 kg/m2 per km/wk run when adjusted for age and declined -0.054+-0.003 kg/m2 (increased 0.021+-0.007 cm) per year of age when adjusted for running distance. Their waist circumference declined-0.096+-0.002 cm per km/wk run when adjusted for age and increased 0.021+-0.007 cm per year of age when adjusted for running distance. These cross-sectional data suggest that age and vigorous exercise interact with each other in affecting mens adiposity, and support the proposition that vigorous physical activity must increase with age to prevent middle-age weight gain. We estimate that a man who ran 16 km/wk at age 25 would need to increase their weekly running distance by 65.7 km/wk by age 50 in order to maintain his same waist circumference.

  20. Preliminary Aging Assessment of Nuclear Air-Treatment and Cooling System Fans

    SciTech Connect (OSTI)

    Winegardner,, W. K.

    1995-07-01

    A preliminary aging assessment of the fans used in nuclear air treatment and cooling systems was performed by the Pacific Northwest Laboratory as part of the U.S. Nuclear Regulatory Commission's Nuclear Plant Aging Research Program. Details from guides and standards for the design, testing, and installation of fans; results of failure surveys; and information concerning stressors, related aging mechanisms, and inspection, surveillance, and monitoring methods (ISMM) were compiled. Failure surveys suggest that about half of the failures reported for fans are primarily associated with aging. Aging mechanisms associated with the various fan components and resulting from mechanical, thermal, and environmental stressors include wear, fatigue, corrosion, and erosion of metals and the deterioration of belts and lubricants. A bearing is the component most frequently linked to fan failure. The assessment also suggests that ISMM that will detect irregularities arising from improper lubrication, cooling, alignment, and balance of the various components should aid in counteracting many of the aging effects that could impair fan performance. An expanded program, to define and evaluate the adequacy of current ISMM and maintenance practices and to include a documented Phase I aging assessment, is recommended.

  1. Consequences of stand age and species functional trait changes on ecosystem water use of forests

    SciTech Connect (OSTI)

    Ewers, Brent; Bond-Lamberty, Benjamin; Mackay, D. Scott

    2011-07-22

    We tested whether using stomatal conductance could capture the dynamic in transpiration with forest age. To do this we by answered the question If we chose a reference stomatal conductance from one stand age of the entire chronosequence to put into a model, would modeled transpiration be biased from the other ages? with a resounding yes. We found that obtaining the right stomatal conductance was crucial for accurate models in two different chronosequences. This strongly suggests that stomatal conductance is the appropriate integrator of inter- and intra-species change in tree transpiration with forest age. If we had tried to use a single reference canopy stomatal conductance, it would not have been able to capture the variability in transpiration with stand age despite the suggestion that hydraulic limitation was consistently acting on the trees; the situation is even more complex in many boreal systems, where a transition to nonstomatal bryophytes may occur over the course of succession. Because we used a biophysical approach, even if our and other researchers chronosequences do not fit the assumptions, the results are still useful. Further, our synthesis of sap flux based estimates of tree transpiration showing a large dynamic suggest that our approach to modeling is crucial in the face of anthropogenic changes to forest age structure. We have now provided the framework for a mechanistically rigorous yet simple approach based on simple tree hydraulics to measuring and modeling stand transpiration with changing forest age and/or species composition.

  2. Energy Saving Melting and Revert Reduction Technology: Aging of Graphitic Cast Irons and Machinability

    SciTech Connect (OSTI)

    Von L. Richards

    2012-09-19

    The objective of this task was to determine whether ductile iron and compacted graphite iron exhibit age strengthening to a statistically significant extent. Further, this effort identified the mechanism by which gray iron age strengthens and the mechanism by which age-strengthening improves the machinability of gray cast iron. These results were then used to determine whether age strengthening improves the machinability of ductile iron and compacted graphite iron alloys in order to develop a predictive model of alloy factor effects on age strengthening. The results of this work will lead to reduced section sizes, and corresponding weight and energy savings. Improved machinability will reduce scrap and enhance casting marketability. Technical Conclusions: ???¢???????¢ Age strengthening was demonstrated to occur in gray iron ductile iron and compacted graphite iron. ???¢???????¢ Machinability was demonstrated to be improved by age strengthening when free ferrite was present in the microstructure, but not in a fully pearlitic microstructure. ???¢???????¢ Age strengthening only occurs when there is residual nitrogen in solid solution in the Ferrite, whether the ferrite is free ferrite or the ferrite lamellae within pearlite. ???¢???????¢ Age strengthening can be accelerated by Mn at about 0.5% in excess of the Mn/S balance Estimated energy savings over ten years is 13.05 trillion BTU, based primarily on yield improvement and size reduction of castings for equivalent service. Also it is estimated that the heavy truck end use of lighter castings for equivalent service requirement will result in a diesel fuel energy savings of 131 trillion BTU over ten years.

  3. Mechanical Testing of TR-55 Rubber Thermally Aged Under Tensile Strain

    Office of Scientific and Technical Information (OSTI)

    (Technical Report) | SciTech Connect Technical Report: Mechanical Testing of TR-55 Rubber Thermally Aged Under Tensile Strain Citation Details In-Document Search Title: Mechanical Testing of TR-55 Rubber Thermally Aged Under Tensile Strain TR-55 rubber specimens were previously subjected to an aging process consisting of the application of a tensile strain of approximately 67%, 100%, 133%, or 167% elongation for 4, 8, 12, or 16 h at either 250 C or room temperature. Control specimens at the

  4. Report on thermal aging effects on tensile properties of ferritic-martensitic steels.

    SciTech Connect (OSTI)

    Li, M.; Soppet, W.K.; Rink, D.L.; Listwan, J.T.; Natesan, K.

    2012-05-10

    This report provides an update on the evaluation of thermal-aging induced degradation of tensile properties of advanced ferritic-martensitic steels. The report is the first deliverable (level 3) in FY11 (M3A11AN04030103), under the Work Package A-11AN040301, 'Advanced Alloy Testing' performed by Argonne National Laboratory, as part of Advanced Structural Materials Program for the Advanced Reactor Concepts. This work package supports the advanced structural materials development by providing tensile data on aged alloys and a mechanistic model, validated by experiments, with a predictive capability on long-term performance. The scope of work is to evaluate the effect of thermal aging on the tensile properties of advanced alloys such as ferritic-martensitic steels, mod.9Cr-1Mo, NF616, and advanced austenitic stainless steel, HT-UPS. The aging experiments have been conducted over a temperature of 550-750 C for various time periods to simulate the microstructural changes in the alloys as a function of time at temperature. In addition, a mechanistic model based on thermodynamics and kinetics has been used to address the changes in microstructure of the alloys as a function of time and temperature, which is developed in the companion work package at ANL. The focus of this project is advanced alloy testing and understanding the effects of long-term thermal aging on the tensile properties. Advanced materials examined in this project include ferritic-martensitic steels mod.9Cr-1Mo and NF616, and austenitic steel, HT-UPS. The report summarizes the tensile testing results of thermally-aged mod.9Cr-1Mo, NF616 H1 and NF616 H2 ferritic-martensitic steels. NF616 H1 and NF616 H2 experienced different thermal-mechanical treatments before thermal aging experiments. NF616 H1 was normalized and tempered, and NF616 H2 was normalized and tempered and cold-rolled. By examining these two heats, we evaluated the effects of thermal-mechanical treatments on material microstructures and associated mechanical properties during long-term aging at elevated temperatures. Thermal aging experiments at different temperatures and periods of time have been completed: 550 C for up to 5000 h, 600 C for up to 7500 h, and 650 C for more than 10,000 h. Tensile properties were measured on thermally aged specimens and aging effect on tensile behavior was assessed. Effects of thermal aging on deformation and failure mechanisms were investigated by using in-situ straining technique with simultaneous synchrotron XRD measurements.

  5. DEUTERIUM, TRITIUM, AND HELIUM DESORPTION FROM AGED TITANIUM TRITIDES. PART I.

    SciTech Connect (OSTI)

    Shanahan, K; Jeffrey Holder, J

    2006-07-10

    Six new samples of tritium-aged bulk titanium have been examined by thermal desorption and isotope exchange chemistry. The discovery of a lower temperature hydrogen desorption state in these materials, previously reported, has been confirmed in one of the new samples. The helium release of the samples shows the more severe effects obtained from longer aging periods, i.e. higher initial He/M ratios. Several of the more aged samples were spontaneously releasing helium. Part I will discuss the new results on the new lower temperature hydrogen desorption state found in one more extensively studied sample. Part II will discuss the hydrogen/helium release behavior of the remaining samples.

  6. DEUTERIUM, TRITIUM, AND HELIUM DESORPTION FROM AGED TITANIUM TRITIDES. PART II.

    SciTech Connect (OSTI)

    Shanahan, K; Jeffrey Holder, J

    2006-08-17

    Six new samples of tritium-aged bulk titanium have been examined by thermal desorption and isotope exchange chemistry. The discovery of a lower temperature hydrogen desorption state in these materials, previously reported, has been confirmed in one of the new samples. The helium release of the samples shows the more severe effects obtained from longer aging periods, i.e. higher initial He/M ratios. Several of the more aged samples were spontaneously releasing helium. Part I discussed the new results on the new lower temperature hydrogen desorption state found in one more extensively studied sample. Part II will discuss the hydrogen/helium release behavior of the remaining samples.

  7. Age-dependent inhibition of pentobarbital sleeping time by ozone in mice and rats

    SciTech Connect (OSTI)

    Canada, A.T.; Calabrese, E.J.; Leonard, D.

    1986-09-01

    The effect of age on the metabolism of pentobarbital in mice and rats was investigated following exposure to 0.3 ppm of ozone for 3.75 hr. Young animals were 2.5 months of age and the mature were 18 months. The pentobarbital sleeping time was significantly prolonged following the ozone exposure in both the mice and rats when compared with an air control. No ozone effect on sleeping time was found in the young animals. The results indicate that there may be an age-related sensitivity to the occurrence of ozone-related inhibition of pentobarbital metabolism.

  8. Effects of aging on the characteristics of TiNiPd shape memory alloy thin films

    SciTech Connect (OSTI)

    Zhang Congchun

    2008-07-15

    TiNiPd thin films have been deposited on glass substrate using R.F. magnetron sputtering. Effects of annealing and aging on the microstructure, phase transformation behaviors and shape memory effects of these thin films have been studied by X-ray diffractometry, differential scanning calorimeter, tensile tests and internal friction characteristics. The TiNiPd thin films annealed at 750 deg. C exhibit uniform martensite/austenite transformations and shape memory effect. Aging at 450 deg. C for 1 h improved the uniformity of transformations and shape memory effect. Long time aging decreased transformation temperatures and increased the brittleness of TiNiPd thin films.

  9. Some aging aspects of DEB getters (Journal Article) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Some aging aspects of DEB getters Citation Details ... OSTI Identifier: 1116888 Report Number(s): LLNL-JRNL-626255 DOE Contract Number: W-7405-ENG-48 Resource Type: Journal ...

  10. Variations in the Retention and Excretion of {sup 137}Cs with Age and Sex

    SciTech Connect (OSTI)

    Boni, A.L.

    2001-08-29

    This report discusses the effects of age and sex on the retention and excretion of {sup 137}Cs in the body in a cross section of the general population over a four-year period.

  11. Organic chemical aging mechanisms: An annotated bibliography. Waste Tank Safety Program

    SciTech Connect (OSTI)

    Samuels, W.D.; Camaioni, D.M.; Nelson, D.A.

    1993-09-01

    An annotated bibliography has been compiled of the potential chemical and radiological aging mechanisms of the organic constituents (non-ferrocyanide) that would likely be found in the UST at Hanford. The majority of the work that has been conducted on the aging of organic chemicals used for extraction and processing of nuclear materials has been in conjunction with the acid or PUREX type processes. At Hanford the waste being stored in the UST has been stabilized with caustic. The aging factors that were used in this work were radiolysis, hydrolysis and nitrite/nitrate oxidation. The purpose of this work was two-fold: to determine whether or not research had been or is currently being conducted on the species associated with the Hanford UST waste, either as a mixture or as individual chemicals or chemical functionalities, and to determine what areas of chemical aging need to be addressed by further research.

  12. Fact #597: November 16, 2009 Median Age of Cars and Trucks Rising in 2008

    Broader source: Energy.gov [DOE]

    The median age of cars and trucks in the U.S. continued to grow in 2008. Due to the economic climate and high gasoline prices that summer, consumers held onto their vehicles longer and delayed new...

  13. Transit times and mean ages for nonautonomous and autonomous compartmental systems

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Rasmussen, Martin; Hastings, Alan; Smith, Matthew J.; Agusto, Folashade B.; Chen-Charpentier, Benito M.; Hoffman, Forrest M.; Jiang, Jiang; Todd-Brown, Katherine E. O.; Wang, Ying; Wang, Ying -Ping; et al

    2016-04-01

    In this study, we develop a theory for transit times and mean ages for nonautonomous compartmental systems. Using the McKendrick–von Förster equation, we show that the mean ages of mass in a compartmental system satisfy a linear nonautonomous ordinary differential equation that is exponentially stable. We then define a nonautonomous version of transit time as the mean age of mass leaving the compartmental system at a particular time and show that our nonautonomous theory generalises the autonomous case. We apply these results to study a nine-dimensional nonautonomous compartmental system modeling the terrestrial carbon cycle, which is a modification of themore » Carnegie–Ames–Stanford approach model, and we demonstrate that the nonautonomous versions of transit time and mean age differ significantly from the autonomous quantities when calculated for that model.« less

  14. New Evidence for the Age of the Youngest Eruptions in the Valles...

    Open Energy Info (EERE)

    reinforce the need to apply a variety of dating methods when evaluating the age of young volcanic events and support the hypothesis that the El Cajete eruptions were part of a...

  15. 230Th/U ages Supporting Hanford Site-Wide Probabilistic Seismic Hazard Analysis

    SciTech Connect (OSTI)

    Paces, James B.

    2014-08-31

    This product represents a USGS Administrative Report that discusses samples and methods used to conduct uranium-series isotope analyses and resulting ages and initial 234U/238U activity ratios of pedogenic cements developed in several different surfaces in the Hanford area middle to late Pleistocene. Samples were collected and dated to provide calibration of soil development in surface deposits that are being used in the Hanford Site-Wide probabilistic seismic hazard analysis conducted by AMEC. The report includes description of sample locations and physical characteristics, sample preparation, chemical processing and mass spectrometry, analytical results, and calculated ages for individual sites. Ages of innermost rinds on a number of samples from five sites in eastern Washington are consistent with a range of minimum depositional ages from 17 ka for cataclysmic flood deposits to greater than 500 ka for alluvium at several sites.

  16. Modeling the mechanical and aging properties of silicone rubber and foam -

    Office of Scientific and Technical Information (OSTI)

    stockpile-historical & additively manufactured materials (Technical Report) | SciTech Connect Technical Report: Modeling the mechanical and aging properties of silicone rubber and foam - stockpile-historical & additively manufactured materials Citation Details In-Document Search Title: Modeling the mechanical and aging properties of silicone rubber and foam - stockpile-historical & additively manufactured materials M97* and M9763 belong to the M97xx series of cellular silicone

  17. Nanoscale dynamics and aging of fibrous peptide-based gels (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect Nanoscale dynamics and aging of fibrous peptide-based gels Citation Details In-Document Search Title: Nanoscale dynamics and aging of fibrous peptide-based gels Authors: Dudukovic, Nikola A. ; Zukoski, Charles F. [1] ; UIUC) [2] + Show Author Affiliations (Buffalo) ( Publication Date: 2014-10-28 OSTI Identifier: 1163382 Resource Type: Journal Article Resource Relation: Journal Name: J. Chem. Phys.; Journal Volume: 141; Journal Issue: (16) ; 10, 2014 Research Org:

  18. Two-Sensor System for Absolute Age and Temperature History - Energy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Innovation Portal Startup America Startup America Industrial Technologies Industrial Technologies Find More Like This Return to Search Two-Sensor System for Absolute Age and Temperature History Sandia National Laboratories Contact SNL About This Technology Publications: PDF Document Publication Market Sheet (718 KB) Technology Marketing Summary Numerous commercial and military applications require knowing the absolute age and/or temperature history of a device or system starting from the

  19. Quench-age method for the fabrication of niobium-aluminum superconductors

    DOE Patents [OSTI]

    Pickus, Milton R.; Ciardella, Robert L.

    1978-01-01

    A flexible Nb.sub.3 Al superconducting wire is fabricated from a niobium-aluminum composite wire by heating to form a solid solution which is retained at room temperature as a metastable solid solution by quenching. The metastable solid solution is then transformed to the stable superconducting A-15 phase by low temperature aging. The transformation induced by aging can be controlled to yield either a multifilamentary or a solid A-15 core surrounded by ductile niobium.

  20. Some aging aspects of DEB getters (Journal Article) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Some aging aspects of DEB getters Citation Details In-Document Search Title: Some aging aspects of DEB getters Authors: Dinh, L N ; Krueger, R ; Cairns, G ; Maxwell, R S Publication Date: 2013-03-04 OSTI Identifier: 1116888 Report Number(s): LLNL-JRNL-626255 DOE Contract Number: W-7405-ENG-48 Resource Type: Journal Article Resource Relation: Journal Name: Journal of Nuclear Materials, vol. 442, na, November 1, 2013, pp. 298

  1. Delta ferrite-containing austenitic stainless steel resistant to the formation of undesirable phases upon aging

    DOE Patents [OSTI]

    Leitnaker, James M.

    1981-01-01

    Austenitic stainless steel alloys containing delta ferrite, such as are used as weld deposits, are protected against the transformation of delta ferrite to sigma phase during aging by the presence of carbon plus nitrogen in a weight percent 0.015-0.030 times the volume percent ferrite present in the alloy. The formation of chi phase upon aging is controlled by controlling the Mo content.

  2. Delta ferrite-containing austenitic stainless steel resistant to the formation of undesirable phases upon aging

    DOE Patents [OSTI]

    Leitnaker, J.M.

    Austenitic stainless steel alloys containing delta ferrite, such as are used as weld deposits, are protected against the transformation of delta ferrite to sigma phase during aging by the presence of carbon plus nitrogen in a weight percent 0.015 to 0.030 times the volume percent ferrite present in the alloy. The formation of chi phase upon aging is controlled by controlling the Mo content.

  3. Using naturally occurring radionuclides to determine drinking water age in a community water system

    SciTech Connect (OSTI)

    Waples, James T.; Bordewyk, Jason K.; Knesting, Kristina M.; Orlandini, Kent A.

    2015-07-22

    Drinking water quality in a community water system is closely linked to the age of water from initial treatment to time of delivery. However, water age is difficult to measure with conventional chemical tracers; particularly in stagnant water, where the relationship between disinfectant decay, microbial growth, and water age is poorly understood. Using radionuclides that were naturally present in source water, we found that measured activity ratios of 90Y/90Sr and 234Th/238U in discrete drinking water samples of known age accurately estimated water age up to 9 days old (σest: ± 3.8 h, P < 0.0001, r2 = 0.998, n = 11) and 25 days old (σest: ± 13.3 h, P < 0.0001, r2 = 0.996, n = 12), respectively. Moreover, 90Y-derived water ages in a community water system (6.8 × 104 m3 d–1 capacity) were generally consistent with water ages derived from an extended period simulation model. Radionuclides differ from conventional chemical tracers in that they are ubiquitous in distribution mains and connected premise plumbing. The ability to measure both water age and an analyte (e.g., chemical or microbe) in any water sample at any time allows for new insight into factors that control drinking water quality.

  4. Tensile Testing of Aged TR-55 Silicone Rubber (Gamma Radiation Under

    Office of Scientific and Technical Information (OSTI)

    Tensile Strain): Load/Unload Cycling Followed by Strain to Failure (Technical Report) | SciTech Connect Technical Report: Tensile Testing of Aged TR-55 Silicone Rubber (Gamma Radiation Under Tensile Strain): Load/Unload Cycling Followed by Strain to Failure Citation Details In-Document Search Title: Tensile Testing of Aged TR-55 Silicone Rubber (Gamma Radiation Under Tensile Strain): Load/Unload Cycling Followed by Strain to Failure Authors: Small IV, W ; Alviso, C T ; Wilson, T S

  5. Beyond Tesla and Edison: Other Luminaries from the Age of Electricity |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Beyond Tesla and Edison: Other Luminaries from the Age of Electricity Beyond Tesla and Edison: Other Luminaries from the Age of Electricity November 25, 2013 - 1:30pm Addthis Electricity pioneer Charles Proteus Steinmetz (center in light-colored suit) poses with Albert Einstein (immediate left) and other inventors at the RCA Brunswick, New Jersey, wireless station in 1921. | Photo courtesy of Franklin Township Public Library Archive. Electricity pioneer Charles Proteus

  6. Effect of Thermal Aging on NO oxidation and NOx storage in a

    Broader source: Energy.gov (indexed) [DOE]

    Fully-Formulated Lean NOx Trap | Department of Energy Thermal aging of LNT has numerous material and chemical effects PDF icon deer09_toops.pdf More Documents & Publications Impacts of Biodiesel on Emission Control Devices NOx Abatement Research and Development CRADA with Navistar Incorporated Thermal Deactivation Mechanisms of Fully-Formed Lean NOx Trap Catalysts Aged by Lean/Rich Cycling

  7. Sixth Status Report: Testing of Aged Softwood Fiberboard Material for the 9975 Shipping Package

    SciTech Connect (OSTI)

    Daugherty, W.

    2015-03-31

    Samples have been prepared from several 9975 lower fiberboard subassemblies fabricated from softwood fiberboard. Physical, mechanical and thermal properties have been measured following varying periods of conditioning in each of several environments. These tests have been conducted in the same manner as previous testing on cane fiberboard samples. Overall, similar aging trends are observed for softwood and cane fiberboard samples, with a few differences. Some softwood fiberboard properties tend to degrade faster in some environments, while some cane fiberboard properties degrade faster in the two most aggressive environments. As a result, it is premature to assume both materials will age at the same rates, and the preliminary aging models developed for cane fiberboard might not apply to softwood fiberboard. However, it is expected that both cane and softwood fiberboard assemblies will perform satisfactorily in conforming packages stored in a typical KAC storage environment for up to 15 years. Samples from an additional 3 softwood fiberboard assemblies have begun aging during the past year to provide information on the variability of softwood fiberboard behavior. Aging and testing of softwood fiberboard will continue and additional data will be collected to support development of an aging model specific to softwood fiberboard.

  8. 230Th-234U Model-Ages of Some Uranium Standard Reference Materials

    SciTech Connect (OSTI)

    Williams, R W; Gaffney, A M; Kristo, M J; Hutcheon, I D

    2009-05-28

    The 'age' of a sample of uranium is an important aspect of a nuclear forensic investigation and of the attribution of the material to its source. To the extent that the sample obeys the standard rules of radiochronometry, then the production ages of even very recent material can be determined using the {sup 230}Th-{sup 234}U chronometer. These standard rules may be summarized as (a) the daughter/parent ratio at time=zero must be known, and (b) there has been no daughter/parent fractionation since production. For most samples of uranium, the 'ages' determined using this chronometer are semantically 'model-ages' because (a) some assumption of the initial {sup 230}Th content in the sample is required and (b) closed-system behavior is assumed. The uranium standard reference materials originally prepared and distributed by the former US National Bureau of Standards and now distributed by New Brunswick Laboratory as certified reference materials (NBS SRM = NBL CRM) are good candidates for samples where both rules are met. The U isotopic standards have known purification and production dates, and closed-system behavior in the solid form (U{sub 3}O{sub 8}) may be assumed with confidence. We present here {sup 230}Th-{sup 234}U model-ages for several of these standards, determined by isotope dilution mass spectrometry using a multicollector ICP-MS, and compare these ages with their known production history.

  9. Powertrain Component Inspection from Mid-Level Blends Vehicle Aging Study

    SciTech Connect (OSTI)

    Shoffner, Brent; Johnson, Ryan; Heimrich, Martin J.; Lochte, Michael

    2010-11-01

    The Energy Independence and Security Act of 2007 calls on the nation to significantly increase its use of renewable fuels to meet its transportation energy needs. The law expands the renewable fuel standard to require use of 36 billion gallons of renewable fuel by 2022. Given that ethanol is the most widely used renewable fuel in the U.S. market, ethanol will likely make up a significant portion of the 36-billion-gallon requirement. The vast majority of ethanol used in the United States is blended with gasoline to create E10-gasoline with up to 10% ethanol. The remaining ethanol is sold in the form of E85 - a gasoline blend with as much as 85% ethanol that can only be used in flexible-fuel vehicles (FFVs). Consumption of E85 is at present limited by both the size of the FFV fleet and the number of E85 fueling stations. Gasoline consumption in the United States is currently about 140 billion gallons per year; thus the maximum use of ethanol as E10 is only about 14 billion gallons. While the U.S. Department of Energy (DOE) remains committed to expanding the E85 infrastructure, that market represented less than 1% of the ethanol consumed in 2010 and will not be able to absorb projected volumes of ethanol in the near term. Because of these factors, DOE and others have been assessing the viability of using mid-level ethanol blends (E15 or E20) as a way to accommodate growing volumes of ethanol. The DOE Mid-Level Ethanol Blends Test Program has been under way since 2007, supported jointly by the Office of the Biomass Program and the Vehicle Technologies Program. One of the larger projects, the Catalyst Durability Study, or Vehicle Aging Study, will be completed early in calendar year 2011. The following report describes a subproject of the Vehicle Aging Study in which powertrain components from 18 of the vehicles were examined at Southwest Research Institute under contract to Oak Ridge National Laboratory (ORNL).

  10. Interactive effects of age and exercise on adiposity measures of41,582 physically active women

    SciTech Connect (OSTI)

    Williams, Paul T.; Satariano William A.

    2004-06-01

    The objective of this report is to assess in women whether exercise affects the estimated age-related increase in adiposity, and contrariwise, whether age affects the estimated exercise-related decrease in adiposity. Cross-sectional analyses of 64,911 female runners who provided data on their body mass index (97.6 percent), waist (91.1percent), and chest circumferences (77.9 percent). Age affected the relationships between vigorous exercise and adiposity. The decline in BMI per km/wk run was linear in 18-25 year olds (-0.023+-0.002 kg/m2 perkm run) and became increasingly nonlinear (convex or upwardly concave) with age. The waist, hip and chest circumferences declined significantly with running distance across all age groups, but the declines were 52-58 percent greater in older than younger women (P<10-5). The relationships between body circumferences and running distance became increasingly convexity (upward concavity) in older women. Conversely, vigorous exercise diminished the apparent increase in adiposity with age. The rise in average BMI with age was greatest in women who ran less than 8 km/week (0.065+-0.005 kg/m2 per y), intermediate of women who ran 8-16km/wk (0.025+-0.004kg/m2 per y) or 16-32 km/wk (0.022+-0.003 kg/m2 pery), and least in those who averaged over 32 km/wk (0.017+-0.001 kg/m2 pery). Before age 45, waist circumference rose 0.055+-0.026 cm in for those who ran 0-8 km/wk, showed no significant change for those who ran 8-40km./wk, and declined -0.057+-0.012 and -0.069+-0.014 cm per year in those who ran 40 -56 and over 56 km/wk. The rise in hip and chest circumferences with age were significantly greater in women who ran under eight km/wk than longer distance runners for hip (0.231+-0.018 vs0.136+-0.004 cm/year) and chest circumferences (0.137+-0.013 vs0.053+-0.003 cm/year). These cross-sectional associations suggest that in women, age and vigorous exercise interact with each other in affecting adiposity. The extent that these cross-sectional associations are causally related to vigorous exercise or are the consequence of self-selection remains to be determined.

  11. The panchromatic Hubble Andromeda Treasury. V. Ages and masses of the year 1 stellar clusters

    SciTech Connect (OSTI)

    Fouesneau, Morgan; Johnson, L. Clifton; Weisz, Daniel R.; Dalcanton, Julianne J.; Williams, Benjamin F.; Bell, Eric F.; Bianchi, Luciana; Caldwell, Nelson; Gouliermis, Dimitrios A.; Guhathakurta, Puragra; Larsen, Sren S.; Rix, Hans-Walter; Seth, Anil C.; Skillman, Evan D.

    2014-05-10

    We present ages and masses for 601 star clusters in M31 from the analysis of the six filter integrated light measurements from near-ultraviolet to near-infrared wavelengths, made as part of the Panchromatic Hubble Andromeda Treasury (PHAT). We derive the ages and masses using a probabilistic technique, which accounts for the effects of stochastic sampling of the stellar initial mass function. Tests on synthetic data show that this method, in conjunction with the exquisite sensitivity of the PHAT observations and their broad wavelength baseline, provides robust age and mass recovery for clusters ranging from ?10{sup 2} to 2 10{sup 6} M {sub ?}. We find that the cluster age distribution is consistent with being uniform over the past 100 Myr, which suggests a weak effect of cluster disruption within M31. The age distribution of older (>100 Myr) clusters falls toward old ages, consistent with a power-law decline of index 1, likely from a combination of fading and disruption of the clusters. We find that the mass distribution of the whole sample can be well described by a single power law with a spectral index of 1.9 0.1 over the range of 10{sup 3}-3 10{sup 5} M {sub ?}. However, if we subdivide the sample by galactocentric radius, we find that the age distributions remain unchanged. However, the mass spectral index varies significantly, showing best-fit values between 2.2 and 1.8, with the shallower slope in the highest star formation intensity regions. We explore the robustness of our study to potential systematics and conclude that the cluster mass function may vary with respect to environment.

  12. Intergrated study of the Devonian-age black shales in eastern Ohio. Final report

    SciTech Connect (OSTI)

    Gray, J.D.; Struble, R.A.; Carlton, R.W.; Hodges, D.A.; Honeycutt, F.M.; Kingsbury, R.H.; Knapp, N.F.; Majchszak, F.L.; Stith, D.A.

    1982-09-01

    This integrated study of the Devonian-age shales in eastern Ohio by the Ohio Department of Natural Resources, Division of Geological Survey is part of the Eastern Gas Shales Project sponsored by the US Department of Energy. The six areas of research included in the study are: (1) detailed stratigraphic mapping, (2) detailed structure mapping, (3) mineralogic and petrographic characterization, (4) geochemical characterization, (5) fracture trace and lineament analysis, and (6) a gas-show monitoring program. The data generated by the study provide a basis for assessing the most promising stratigraphic horizons for occurrences of natural gas within the Devonian shale sequence and the most favorable geographic areas of the state for natural gas exploration and should be useful in the planning and design of production-stimulation techniques. Four major radioactive units in the Devonian shale sequence are believed to be important source rocks and reservoir beds for natural gas. In order of potential for development as an unconventional gas resource, they are (1) lower and upper radioactive facies of the Huron Shale Member of the Ohio Shale, (2) upper Olentangy Shale (Rhinestreet facies equivalent), (3) Cleveland Shale Member of the Ohio Shale, and (4) lower Olentangy Shale (Marcellus facies equivalent). These primary exploration targets are recommended on the basis of areal distribution, net thickness of radioactive shale, shows of natural gas, and drilling depth to the radioactive unit. Fracture trends indicate prospective areas for Devonian shale reservoirs. Good geological prospects in the Devonian shales should be located where the fracture trends coincide with thick sequences of organic-rich highly radioactive shale.

  13. Modeled tephra ages from lake sediments, base of Redoubt Volcano, Alaska

    SciTech Connect (OSTI)

    Schiff, C J; Kaufman, D S; Wallace, K L; Werner, A; Ku, T L; Brown, T A

    2007-02-25

    A 5.6-m-long lake sediment core from Bear Lake, Alaska, located 22 km southeast of Redoubt Volcano, contains 67 tephra layers deposited over the last 8750 cal yr, comprising 15% of the total thickness of recovered sediment. Using 12 AMS {sup 14}C ages, along with the {sup 137}Cs and {sup 210}Pb activities of recent sediment, we evaluated different models to determine the age-depth relation of sediment, and to determine the age of each tephra deposit. The age model is based on a cubic smooth spline function that was passed through the adjusted tephra-free depth of each dated layer. The estimated age uncertainty of the 67 tephras averages {+-} 105 yr (1{sigma}). Tephra-fall frequency at Bear Lake was among the highest during the past 500 yr, with eight tephras deposited compared to an average of 3.7 per 500 yr over the last 8500 yr. Other periods of increased tephra fall occurred 2500-3500, 4500-5000, and 7000-7500 cal yr. Our record suggests that Bear Lake experienced extended periods (1000-2000 yr) of increased tephra fall separated by shorter periods (500-1000 yr) of apparent quiescence. The Bear Lake sediment core affords the most comprehensive tephrochronology from the base of the Redoubt Volcano to date, with an average tephra-fall frequency of once every 130 yr.

  14. NO2 Aging and Iodine Loading of Silver-Functionalized Aerogels

    SciTech Connect (OSTI)

    Patton, K K [ORNL; Bruffey, S H [ORNL; Walker, J F [ORNL; Jubin, R T [ORNL

    2014-07-31

    Off-gas treatment systems in used fuel reprocessing which use fixed-bed adsorbers are typically designed to operate for an extended period of time before replacement or regeneration of the adsorbent. During this time, the sorbent material will be exposed to the off-gas stream. Exposure could last for months, depending on the replacement cycle time. The gas stream will be at elevated temperature and will possibly contain a mixture of water vapor, NOx, nitric acid vapors, and a variety of other constituents in addition to the radionuclides of capture interest. A series of studies were undertaken to evaluate the effects of long-term exposure, or aging, on proposed iodine sorbent materials under increasingly harsh off-gas conditions. Previous studies have evaluated the effects of up to 6 months of aging under dry air and under humid air conditions on the iodine loading behavior of Ag0-functionalized aerogels. This study examines the effects of extended exposure (up to 6 months) to NO2 on the iodine loading capacity of Ag0- functionalized aerogels. Material aged for 1 and 2 months appeared to have a similar total loading capacity to fresh material. Over an aging period of 4 months, a loss of approximately 15% of the total iodine capacity was seen. The iodine capacity loss on silver-functionalized aerogels due to NO2 was smaller than the iodine capacity loss due to humid or dry air aging.

  15. Estimating Small-area Populations by Age and Sex Using Spatial Interpolation and Statistical Inference Methods

    SciTech Connect (OSTI)

    Qai, Qiang; Rushton, Gerald; Bhaduri, Budhendra L; Bright, Eddie A; Coleman, Phil R

    2006-01-01

    The objective of this research is to compute population estimates by age and sex for small areas whose boundaries are different from those for which the population counts were made. In our approach, population surfaces and age-sex proportion surfaces are separately estimated. Age-sex population estimates for small areas and their confidence intervals are then computed using a binomial model with the two surfaces as inputs. The approach was implemented for Iowa using a 90 m resolution population grid (LandScan USA) and U.S. Census 2000 population. Three spatial interpolation methods, the areal weighting (AW) method, the ordinary kriging (OK) method, and a modification of the pycnophylactic method, were used on Census Tract populations to estimate the age-sex proportion surfaces. To verify the model, age-sex population estimates were computed for paired Block Groups that straddled Census Tracts and therefore were spatially misaligned with them. The pycnophylactic method and the OK method were more accurate than the AW method. The approach is general and can be used to estimate subgroup-count types of variables from information in existing administrative areas for custom-defined areas used as the spatial basis of support in other applications.

  16. DOE-sponsored aging management guideline for electrical cable and terminators

    SciTech Connect (OSTI)

    Gazdzinski, R.F.

    1996-03-01

    The DOE-sponsored Aging Management Guideline (AMG) for Electrical Cable and Terminations provides an analysis of the potential age-related degradation mechanisms and effects for low-voltage and medium-voltage extruded cables and associated terminations used in commercial nuclear power plants. The AMG examined historical industry failure data and correlated this with postulated aging mechanisms and effects. Existing and developmental testing and condition monitoring techniques were evaluated, as well as current industry practices, in order to assess whether all significant aging mechanisms/effects are being effectively managed. Results of the study indicate that some aging mechanisms and effects are not directly addressed by current industry maintenance and surveillance practices; however, empirical evidence indicates that low- and medium-voltage cable and terminations are in general very reliable. A limited number of nondestructive (or essentially nondestructive) techniques currently available are potentially useful for evaluating low-voltage cable condition; however, such techniques do not currently exist for monitoring medium-voltage cable. Troubleshooting or diagnostic techniques are available to identify certain types of degradation.

  17. Understanding and managing the effects of battery charger and inverter aging

    SciTech Connect (OSTI)

    Gunther, W. ); Aggarwal, S. )

    1992-01-01

    An aging assessment of battery chargers and inverters was conducted under the auspices of the NRC's Nuclear Plant Aging Research (NPAR) Program. The intentions of this program are to resolve issues related to the aging and service wear of equipment and systems at operating reactor facilities and to assess their impact on safety. Inverters and battery chargers are used in nuclear power plants to perform significant functions related to plant safety and availability. The specific impact of a battery charger or inverter failure varies with plant configuration. Operating experience data have demonstrated that reactor trips, safety injection system actuations, and inoperable emergency core cooling systems have resulted from inverter failures; and dc bus degradation leading to diesel generator inoperability or loss of control room annunication and indication have resulted from battery and battery charger failures. For the battery charger and inverter, the aging and service wear of subcomponents have contributed significantly to equipment failures. This paper summarizes the data and then describes methods that can be used to detect battery charger and inverter degradation prior to failure, as well as methods to minimize the failure effects. In both cases, the managing of battery charger and inverter aging is emphasized. 5 refs.

  18. Understanding and managing the effects of battery charger and inverter aging

    SciTech Connect (OSTI)

    Gunther, W.; Aggarwal, S.

    1992-06-01

    An aging assessment of battery chargers and inverters was conducted under the auspices of the NRC`s Nuclear Plant Aging Research (NPAR) Program. The intentions of this program are to resolve issues related to the aging and service wear of equipment and systems at operating reactor facilities and to assess their impact on safety. Inverters and battery chargers are used in nuclear power plants to perform significant functions related to plant safety and availability. The specific impact of a battery charger or inverter failure varies with plant configuration. Operating experience data have demonstrated that reactor trips, safety injection system actuations, and inoperable emergency core cooling systems have resulted from inverter failures; and dc bus degradation leading to diesel generator inoperability or loss of control room annunication and indication have resulted from battery and battery charger failures. For the battery charger and inverter, the aging and service wear of subcomponents have contributed significantly to equipment failures. This paper summarizes the data and then describes methods that can be used to detect battery charger and inverter degradation prior to failure, as well as methods to minimize the failure effects. In both cases, the managing of battery charger and inverter aging is emphasized. 5 refs.

  19. Predicting age of ovarian failure after radiation to a field that includes the ovaries

    SciTech Connect (OSTI)

    Wallace, W. Hamish B. . E-mail: Hamish.Wallace@ed.ac.uk; Thomson, Angela B.; Saran, Frank; Kelsey, Tom W.

    2005-07-01

    Purpose: To predict the age at which ovarian failure is likely to develop after radiation to a field that includes the ovary in women treated for cancer. Methods and Materials: Modern computed tomography radiotherapy planning allows determination of the effective dose of radiation received by the ovaries. Together with our recent assessment of the radiosensitivity of the human oocyte, the effective surviving fraction of primordial oocytes can be determined and the age of ovarian failure, with 95% confidence limits, predicted for any given dose of radiotherapy. Results: The effective sterilizing dose (ESD: dose of fractionated radiotherapy [Gy] at which premature ovarian failure occurs immediately after treatment in 97.5% of patients) decreases with increasing age at treatment. ESD at birth is 20.3 Gy; at 10 years 18.4 Gy, at 20 years 16.5 Gy, and at 30 years 14.3 Gy. We have calculated 95% confidence limits for age at premature ovarian failure for estimated radiation doses to the ovary from 1 Gy to the ESD from birth to 50 years. Conclusions: We report the first model to reliably predict the age of ovarian failure after treatment with a known dose of radiotherapy. Clinical application of this model will enable physicians to counsel women on their reproductive potential following successful treatment.

  20. Letter report: Population estimates by age, sex and race for 10-county study area

    SciTech Connect (OSTI)

    Pittenger, D B

    1992-02-01

    The Hanford Environmental Does Reconstruction (HEDR) Project was established to estimate radiation doses that people could have received from nuclear operations at the Hanford Site since 1944. To identify groups that may have received doses, population estimates containing age, race, and sex detail for ten counties in Washington and Oregon for the years 1940 to 1980 were prepared by the Demographics Laboratory under a subcontract with the Pacific Northwest Laboratory (PNL). A data base of population information was developed from census reports and published and unpublished collections from the Washington State Office of Financial Management and Center for Population Research. Three estimation methods were then explored: the cohort-component model, cohort interpolation, and age-group interpolation. The estimates generated through cohort and age-group interpolation are considered adequate for initial use in the HEDR Project. Results are presented in two forms: (1) county populations by sex and single year of age and (2) county populations by sex and race for age groupings. These results are made available to the HEDR Project for further refinement into population estimates by county census divisions.

  1. Chaotic behavior of light-assisted physical aging in arsenoselenide glasses

    SciTech Connect (OSTI)

    Shpotyuk, O.; Kozdras, A.; Hacinliyan, A. S.; Skarlatos, Y.; Kusbeyzi Aybar, I.; Aybar, O. O.

    2014-12-15

    The theory of strange attractors is shown to be adequately applicable for analyzing the kinetics of light-assisted physical aging revealed in structural relaxation of Se-rich As-Se glasses below glass transition. Kinetics of enthalpy losses is used to determine the phase space reconstruction parameters. Observed chaotic behaviour (involving chaos and fractal consideration such as detrended fluctuation analysis, attractor identification using phase space representation, delay coordinates, mutual information, false nearest neighbours, etc.) reconstructed via the TISEAN program package is treated within a microstructure model describing multistage aging behaviour in arsenoselenide glasses. This simulation testifies that photoexposure acts as an initiating factor only at the beginning stage of physical aging, thus facilitating further atomic shrinkage of a glassy backbone.

  2. Distinctive microstructural features of aged sodium silicate-activated slag concretes

    SciTech Connect (OSTI)

    San Nicolas, Rackel; Bernal, Susan A.; Meja de Gutirrez, Ruby; Deventer, Jannie S.J. van; Provis, John L.

    2014-11-15

    Electron microscopic characterisation of 7-year old alkali-activated blast-furnace slag concretes enabled the identification of distinct microstructural features, providing insight into the mechanisms by which these materials evolve over time. Backscattered electron images show the formation of Liesegang-type ring formations, suggesting that the reaction at advanced age is likely to follow an Oswald supersaturationnucleationdepletion cycle. Segregation of Ca-rich veins, related to the formation of Ca(OH){sub 2}, is observed in microcracked regions due to the ongoing reaction between the pore solution and available calcium from remnant slag grains. A highly dense and uniform interfacial transition zone is identified between siliceous aggregate particles and the alkali activated slag binders, across the concretes assessed. Alkali-activated slag concretes retain a highly dense and stable microstructure at advanced ages, where any microcracks induced at early ages seem to be partially closing, and the remnant slag grains continue reacting.

  3. Spectroscopic studies of the 110{degree}C thermal aging of PETN

    SciTech Connect (OSTI)

    Dosser, L.R.; Seliskar, C.J.

    1992-07-30

    The 110{degrees}C thermal aging parameters, including initial rates of decomposition, of four types of pentaerythritol tetranitrate (PETN) over a period of ten months are presented. Both decomposition products nitric oxide, NO, and nitrogen dioxide, N0{sub 2} were monitored from multiple, hermetically-sealed, in vacuo samples. Nitric oxide appears to be the first nitrogen oxide product evolved. Nitrogen dioxide produced by abrupt thermal aging is more slowly converted to nitric oxide by a 1:1 process. The behavior of samples of RR5K PETN was significantly different from that of other powders studied. Further work is in progress to better define the thermal aging of RR5K PETN.

  4. Evidence of transition-metal accumulation on aged graphite anodes by SIMS.

    SciTech Connect (OSTI)

    Abraham, D. P.; Spila, T.; Furczon, M. M.; Sammann, E.; Chemical Sciences and Engineering Division; Univ. of Illinois

    2008-01-01

    In cells containing Li{sub 1.05}(Ni{sub 1/3}Co{sub 1/3}Mn{sub 1/3}){sub 0.95}O{sub 2}-based positive and graphite-based negative electrodes, a significant portion of cell impedance rise on aging is known to be from the negative electrode. One possible reason for this impedance rise is the dissolution of transition-metal elements from the oxide electrode that accumulate and create a high-impedance layer at the negative electrode-electrolyte interface. This article details dynamic secondary ion mass spectrometry (SIMS) measurements, which provide a relative comparison of Mn, Co, and Ni contents on fresh, formed, and aged graphite electrodes. The data clearly indicate that these transition-metal elements accumulate at the electrode surface and diffuse into the electrode during cell aging.

  5. Variation of Radiative Properties During Black Carbon Aging. Theoretical and Experimental Intercomparison

    SciTech Connect (OSTI)

    He, Cenlin; Liou, K. N.; Takano, Y.; Zhang, Renyi; Zamora, Misty L.; Yang, Ping; Li, Qinbin; Leung, Lai-Yung R.

    2015-10-28

    A theoretical model is developed to account for black carbon (BC) aging during three major evolution stages, i.e., freshly emitted aggregates, coated particles by soluble materials, and those after further hygroscopic growth. The geometric-optics surface-wave approach is employed to compute BC single-scattering properties at each stage, which are compared with laboratory measurements. Theoretical predictions using input parameters determined from experiments are consistent with measurements in extinction and scattering cross sections for coated BC (within 30 20%) and absorption enhancement from coating (within 15%). The calculated scattering cross sections of fresh BC aggregates are larger than those experimentally measured, because of uncertainties in measurements and calculations. We apply the aging model to compute BC direct radiative forcing (DRF) over the LA Basin using the CalNex 2010 field measurements. Our results demonstrate that accounting for the interactive radiative properties during BC aging is essential in obtaining reliable DRF estimates within a regional context.

  6. Superheated-steam test of ethylene propylene rubber cables using a simultaneous aging and accident environment

    SciTech Connect (OSTI)

    Bennett, P.R.; St. Clair, S.D.; Gilmore, T.W.

    1986-06-01

    The superheated-steam test exposed different ethylene propylene rubber (EPR) cables and insulation specimens to simultaneous aging and a 21-day simultaneous accident environment. In addition, some insulation specimens were exposed to five different aging conditions prior to the 21-day simultaneous accident simulation. The purpose of this superheated-steam test (a follow-on to the saturated-steam tests (NUREG/CR-3538)) was to: (1) examine electrical degradation of different configurations of EPR cables; (2) investigate differences between using superheated-steam or saturated-steam at the start of an accident simulation; (3) determine whether the aging technique used in the saturated-steam test induced artificial degradation; and (4) identify the constituents in EPR that affect moisture absorption.

  7. Significance of locally intensified strain aging to the fracture toughness of welded steel structures

    SciTech Connect (OSTI)

    Dawes, M.G.

    1995-12-31

    A review of past studies shows that tests on specimens notched after welding can give overestimates of the fracture toughness that occurs at the tips of flaws present during welding. This situation results from locally intensified straining and aging embrittlement (LISAE), which has been shown to trigger low stress brittle fractures in both notched and welded wide plate tension tests, and welded structures in service. Although the relative susceptibilities of steels to strain aging embrittlement are sometimes assessed by testing bulk strained and aged samples, the results of such tests may be optimistic. A summary is given of work to develop a fracture toughness test method for LISAE. The new test will give increased confidence and accuracy in fracture assessments, be of use in selecting tough materials, and aid the development of materials that are resistant to LISAE.

  8. Assessment of interfacial microstructure and bond properties in aged GRC using a novel microindentation method

    SciTech Connect (OSTI)

    Zhu, W.; Bartos, P.J.M.

    1997-11-01

    Changes of microstructure and properties in the interfacial zone of glass fiber reinforced cement (GRC) under the effect of aging were investigated. A novel technique based on a microindentation apparatus was developed and successfully used to carry out microstrength testing in the interfacial area and push-in tests on selected individual fibers within a strand. By continuously monitoring load vs. displacement, the new technique allowed the microstrength to be measured in small, porous areas of the fiber-matrix interfacial zone, and particularly within the glass fiber strand/bundle. The results showed that the embrittlement of aged GRC was closely associated with a substantial increase of the microstrength values within the fiber bundle during the aging process. It was also revealed that a wide range of bond properties existed within the fiber strand. The resistance to fiber sliding was much greater at the outer filaments than at the inner central filaments of the fiber strand/bundle.

  9. Ozone induces glucose intolerance and systemic metabolic effects in young and aged brown Norway rats

    SciTech Connect (OSTI)

    Bass, V.; Gordon, C.J.; Jarema, K.A.; MacPhail, R.C.; Cascio, W.E.; Phillips, P.M.; Ledbetter, A.D.; Schladweiler, M.C.; Andrews, D.; Miller, D.; Doerfler, D.L.; Kodavanti, U.P.

    2013-12-15

    Air pollutants have been associated with increased diabetes in humans. We hypothesized that ozone would impair glucose homeostasis by altering insulin signaling and/or endoplasmic reticular (ER) stress in young and aged rats. One, 4, 12, and 24 month old Brown Norway (BN) rats were exposed to air or ozone, 0.25 or 1.0 ppm, 6 h/day for 2 days (acute) or 2 d/week for 13 weeks (subchronic). Additionally, 4 month old rats were exposed to air or 1.0 ppm ozone, 6 h/day for 1 or 2 days (time-course). Glucose tolerance tests (GTT) were performed immediately after exposure. Serum and tissue biomarkers were analyzed 18 h after final ozone for acute and subchronic studies, and immediately after each day of exposure in the time-course study. Age-related glucose intolerance and increases in metabolic biomarkers were apparent at baseline. Acute ozone caused hyperglycemia and glucose intolerance in rats of all ages. Ozone-induced glucose intolerance was reduced in rats exposed for 13 weeks. Acute, but not subchronic ozone increased ?{sub 2}-macroglobulin, adiponectin and osteopontin. Time-course analysis indicated glucose intolerance at days 1 and 2 (2 > 1), and a recovery 18 h post ozone. Leptin increased day 1 and epinephrine at all times after ozone. Ozone tended to decrease phosphorylated insulin receptor substrate-1 in liver and adipose tissues. ER stress appeared to be the consequence of ozone induced acute metabolic impairment since transcriptional markers of ER stress increased only after 2 days of ozone. In conclusion, acute ozone exposure induces marked systemic metabolic impairments in BN rats of all ages, likely through sympathetic stimulation. - Highlights: Air pollutants have been associated with increased diabetes in humans. Acute ozone exposure produces profound metabolic alterations in rats. Age influences metabolic risk factors in aging BN rats. Acute metabolic effects are reversible and repeated exposure reduces these effects. Ozone metabolic effects are only slightly exacerbated in geriatric rats.

  10. FIFTH STATUS REPORT: TESTING OF AGED SOFTWOOD FIBERBOARD MATERIAL FOR THE 9975 SHIPPING PACKAGE

    SciTech Connect (OSTI)

    Daugherty, W.; Skidmore, E.; Dunn, K.

    2014-04-15

    Samples have been prepared from a 9975 lower fiberboard subassembly fabricated from softwood fiberboard. Physical, mechanical and thermal properties have been measured following varying periods of conditioning in each of several environments. These tests have been conducted in the same manner as previous testing on cane fiberboard samples. Overall, similar aging trends are observed for softwood and cane fiberboard samples, with a few differences. Some softwood fiberboard properties tend to degrade faster in elevated humidity environments, while some cane fiberboard properties degrade faster in the hotter dry environments. As a result, it is premature to assume both materials will age at the same rates, and the preliminary aging models developed for cane fiberboard might not apply to softwood fiberboard. However, it is expected that both cane and softwood fiberboard assemblies will perform satisfactorily in conforming packages stored in a typical KAC storage environment for up to 15 years. Aging and testing of softwood fiberboard will continue and additional data will be collected. Additional samples will be added to each aging environment, to support development of an aging model specific to softwood fiberboard. Post-conditioning data have been measured on samples from a single softwood fiberboard assembly, and baseline data are also available from a limited number of vendor-provided samples. This provides minimal information on the possible sample-to-sample variation exhibited by softwood fiberboard. Data to date are generally consistent with the range seen in cane fiberboard, but some portions of the data trends are skewed toward the lower end of that range. Two additional softwood fiberboard source packages have been obtained and will begin to provide data on the range of variability of this material.

  11. Stellar age spreads in clusters as imprints of cluster-parent clump densities

    SciTech Connect (OSTI)

    Parmentier, G.; Grebel, E. K.; Pfalzner, S.

    2014-08-20

    It has recently been suggested that high-density star clusters have stellar age distributions much narrower than that of the Orion Nebula Cluster, indicating a possible trend of narrower age distributions for denser clusters. We show this effect to likely arise from star formation being faster in gas with a higher density. We model the star formation history of molecular clumps in equilibrium by associating a star formation efficiency per free-fall time, ?{sub ff}, to their volume density profile. We focus on the case of isothermal spheres and we obtain the evolution with time of their star formation rate. Our model predicts a steady decline of the star formation rate, which we quantify with its half-life time, namely, the time needed for the star formation rate to drop to half its initial value. Given the uncertainties affecting the star formation efficiency per free-fall time, we consider two distinct values: ?{sub ff} = 0.1 and ?{sub ff} = 0.01. When ?{sub ff} = 0.1, the half-life time is of the order of the clump free-fall time, ?{sub ff}. As a result, the age distributions of stars formed in high-density clumps have smaller full-widths at half-maximum than those of stars formed in low-density clumps. When the star formation efficiency per free-fall time is 0.01, the half-life time is 10 times longer, i.e., 10 clump free-fall times. We explore what happens if the duration of star formation is shorter than 10?{sub ff}, that is, if the half-life time of the star formation rate cannot be defined. There, we build on the invariance of the shape of the young cluster mass function to show that an anti-correlation between the clump density and the duration of star formation is expected. We therefore conclude that, regardless of whether the duration of star formation is longer than the star formation rate half-life time, denser molecular clumps yield narrower star age distributions in clusters. Published densities and stellar age spreads of young clusters and star-forming regions actually suggest that the timescale for star formation is of order 1-4?{sub ff}. We also discuss how the age bin size and uncertainties in stellar ages affect our results. We conclude that there is no need to invoke the existence of multiple cluster formation mechanisms to explain the observed range of stellar age spreads in clusters.

  12. Ageing effect in spray pyrolysed B:SnO{sub 2} thin films for LPG sensing

    SciTech Connect (OSTI)

    Skariah, Benoy E-mail: dr.boben1@gmail.com; Thomas, Boben E-mail: dr.boben1@gmail.com

    2014-10-15

    For LPG sensing, boron doped (0.2 to 0.8 wt. %) polycrystalline tin oxide thin films are deposited by spray pyrolysis in the temperature range 325 - 430 C. Sensor response of 56 % is achieved for 1000 ppm of LPG, at an operating temperature of 350 C. The effects of ageing under ambient conditions on the sensor response are investigated for a storage period of six years. Ageing increases the film resistance but the gas response is lowered. XRD, SEM, FESEM, FTIR and XPS are utilized for structural, morphological and compositional charaterisations.

  13. Examination of 80 deg. C desorption isotherms of tritium aged Pd/k and LANA.75

    SciTech Connect (OSTI)

    Staack, G. C.; Shanahan, K. L.; Walters, R. T.; Pilgrim, R. D.

    2008-07-15

    Metal hydrides, specifically Pd deposited on kieselguhr (Pd/k) and LaNi{sub 4.25}Al{sub 0.75} (LANA.75), have been used at the Savannah River Site for almost twenty years for hydrogen isotope separation and storage. Radiolytic decay of tritium to helium-3 in the metal matrix causes three classic changes in the performance of the hydride: the plateau pressure decreases, the plateau slope increases, and a heel forms, reducing the reversible capacity of the hydride. Deuterium and tritium isotherms were collected on the virgin materials, only tritium isotherms were collected at approximately 2 years, and both deuterium and tritium isotherms were collected at approximately 3.5 years of quiescent aging at 26 deg. C. Each sample was loaded to 0.5-0.6 T/M prior to each aging period. Points of interest include comparisons of each sample at different aging periods and isotope effects on aged hydride isotherms. Partial restoration of thermodynamic properties by sample cycling has been observed in LANA. 75, though not previously reported in Pd. The methods and results are presented. (authors)

  14. Low-Dose, Ionizing Radiation and Age-Related Changes in Skeletal Microarchitecture

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Alwood, Joshua S.; Kumar, Akhilesh; Tran, Luan H.; Wang, Angela; Limoli, Charles L.; Globus, Ruth K.

    2012-01-01

    Osteoporosis can profoundly affect the aged as a consequence of progressive bone loss; high-dose ionizing radiation can cause similar changes, although less is known about lower doses (≤100 cGy). We hypothesized that exposure to relatively low doses of gamma radiation accelerates structural changes characteristic of skeletal aging. Mice (C57BL/6J-10 wk old, male) were irradiated (total body; 0-sham, 1, 10 or 100 cGy 137 Cs) and tissues harvested on the day of irradiation, 1 or 4 months later. Microcomputed tomography was used to quantify microarchitecture of high turnover, cancellous bone. Irradiation at 100 cGy caused transient microarchitectural changes over one month that were only evidentmore » at longer times in controls (4 months). Ex vivo bone cell differentiation from the marrow was unaffected by gamma radiation. In conclusion, acute ionizing gamma irradiation at 100 cGy (but not at 1 cGy or 10 cGy) exacerbated microarchitectural changes normally found during progressive, postpubertal aging prior to the onset of age-related osteoporosis.« less

  15. Effects of main-sequence mass loss on the turnoff ages of globular clusters

    SciTech Connect (OSTI)

    Guzik, J.A.

    1989-01-01

    Willson, Bowen, and Struck-Marcell have proposed that globular cluster main-sequence turnoff ages can be reconciled with the lower ages of the Galaxy and universe deduced from other methods by incorporating an epoch of early main-sequence mass-loss by stars of spectral types A through early-F. The proposed mass loss is pulsation-driven, and facilitated by rapid rotation. This paper presents stellar evolution calculations of Pop. II (Z = 0.001) mass-losing stars of initial mass 0.8 to 1.6 M/sub /circle dot//, with exponentially-decreasing mass loss rates of e-folding times 0.5 to 2.0 Gyr, evolving to a final mass of 0.7 M/sub /circle dot//. The calculations indicate that a globular cluster with apparent turnoff age 18 Gyr could have an actual age as low as /approximately/12 Gyr. Observational implications that may help to verify the hypothesis, e.g. low C/N abundance ratios among red giants following first dredge-up, blue stragglers, red giant deficiencies, and signatures in cluster mass/luminosity functions, are also discussed.25 refs., 4 figs., 3 tabs.

  16. Summary Report of Cable Aging and Performance Data for Fiscal Year 2014.

    SciTech Connect (OSTI)

    Celina, Mathias C.; Celina, Mathias C.; Redline, Erica Marie; Redline, Erica Marie; Bernstein, Robert; Bernstein, Robert; Quintana, Adam; Quintana, Adam; Giron, Nicholas Henry; Giron, Nicholas Henry; White II, Gregory Von; White II, Gregory Von

    2014-09-01

    As part of the Light Water Reactor Sustainability Program, science - based engineering approaches were employed to address cable degradation behavior under a range of exposure environments. Experiments were conducted with the goal to provide best guidance for aged material states, remaining life and expected performance under specific conditions for a range of cable materials. Generic engineering tests , which focus on rapid accelerated aging and tensile elongation , were combined with complementar y methods from polymer degradation science. Sandia's approach, building on previous years' efforts, enabled the generation of some of the necessary data supporting the development of improved lifetime predictions models, which incorporate known material b ehaviors and feedback from field - returned 'aged' cable materials. Oxidation rate measurements have provided access to material behavior under low dose rate thermal conditions, where slow degradation is not apparent in mechanical property changes. Such da ta have shown aging kinetics consistent with established radiati on - thermal degradation models. ACKNOWLEDGEMENTS We gratefully acknowledge ongoing technical support at the LICA facility and extensive sample handling provided by Maryla Wasiolek and Don Hans on. Sam Durbin and Patrick Mattie are recognized for valuable guidance throughout the year and assistance in the preparation of the final report. Doug Brunson is appreciated for sample analysis, compilation and plotting of experimental data.

  17. Basic study of the aging process in solid-dielectric cables (second annual report)

    SciTech Connect (OSTI)

    Not Available

    1982-02-01

    This research program has the two basic objectives of developing an understanding of the basic mechanisms of dielectric aging and of developing an accelerated laboratory test for predicting the service life of underground power transmission cable insulated with solid polyolefin dielectrics. For purposes of this program the polyolefins of interest are limited to conventional low-density polyethylene (LDPE), peroxide-cross-linked, low-density polyethylene (XLPE), and ethylene-propylene rubber (EPR). The program was divided into four sequential tasks: state-of-the-art review of the physics and chemistry of dielectric aging, accelerated life testing, and selected closely related subjects; development of molecular-level models of the dielectric aging process; verification of the aging model through laboratory experimentation with model cables and studies of dielectric material behavior; and development of an accelerated test method and verification of test with full-sized power cable. The general goals and scope of Tasks 1 and 2, which have been completed are reviewed. The initial planning and implementation of Task 3 are described, with detailed discussion of the following activities: detailed planning and initiation of experiments with model cables and slab materials; selection of materials and designs for model cables; manufacture of model cables; evaluation of dielectric materials used for model cable manufacture; establishment of baseline characteristics of model cables; identification of critical equipment and instrument needs; and initial experimental results. (LCL)

  18. AmeriFlux US-Me2 Metolius-intermediate aged ponderosa pine

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Law, Bev [Oregon State University

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Me2 Metolius-intermediate aged ponderosa pine. Site Description - The mean stand age is 64 years old and the stand age of the oldest trees is about 100 years old. This site is one of the Metolius cluster sites with different age and disturbance classes and part of the AmeriFlux network (http://ameriflux.ornl.gov/fullsiteinfo.php?sid=88). The overstory is almost exclusively composed of ponderosa pine trees (Pinus ponderosa Doug. Ex P. Laws) with a few scattered incense cedars (Calocedrus decurrens (Torr.) Florin) and has a peak leaf area index (LAI) of 2.8 m2 m-2. Tree height is relatively homogeneous at about 16 m, and the mean tree density is approximately 325 trees ha-1 (Irvine et al., 2008). The understory is sparse with an LAI of 0.2 m2 m-2 and primarily composed of bitterbrush (Purshia tridentate (Push) DC.) and Manzanita (Arctostaphylos patula Greene). Soils at the site are sandy (69%/24%/7% sand/silt/clay at 0–0.2 m depth and 66%/27%/7% at 0.2–0.5 m depth, and 54%/ 35%/11% at 0.5–1.0 m depth), freely draining with a soil depth of approximately 1.5 m (Irvine et al., 2008; Law et al., 2001b; Schwarz et al., 2004).

  19. AGING BEHAVIOR OF VITON O-RING SEALS IN THE 9975 SHIPPING PACKAGE

    SciTech Connect (OSTI)

    Skidmore, E.; Daugherty, W.; Hoffman, E.; Dunn, K.; Bellamy, S.

    2012-01-13

    The Savannah River Site (SRS) is storing plutonium (Pu) materials in the K-Area Materials Storage (KAMS) facility. The Pu materials were packaged according to the DOE-STD-3013 standard and shipped to the SRS in Type B 9975 packages. The robust 9975 shipping package was not designed for long-term product storage, but it is a specified part of the storage configuration and the KAMS facility safety basis credits the 9975 design with containment. Within the 9975 package, nested stainless steel containment vessels are closed with dual O-ring seals based on Viton{reg_sign} GLT or GLT-S fluoroelastomer. The aging behavior of the O-ring compounds is being studied to provide the facility with advanced notice of nonconformance and to develop life prediction models. A combination of field surveillance, leak testing of surrogate fixtures aged at bounding service temperatures, and accelerated-aging methodologies based on compression stress-relaxation and oxygen consumption analysis is being used to evaluate seal performance. A summary of the surveillance program relative to seal aging behavior is presented.

  20. Variation of the radiative properties during black carbon aging: theoretical and experimental intercomparison

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    He, C.; Liou, K.-N.; Takano, Y.; Zhang, R.; Zamora, M. L.; Yang, P.; Li, Q.; Leung, L. R.

    2015-07-20

    A theoretical black carbon (BC) aging model is developed to account for three typical evolution stages, namely, freshly emitted aggregates, coated BC by soluble material, and BC particles undergoing further hygroscopic growth. The geometric-optics surface-wave (GOS) approach is employed to compute the BC single-scattering properties at each aging stage, which are subsequently compared with laboratory measurements. Theoretical calculations are consistent with measurements in extinction and absorption cross sections for fresh BC aggregates, but overestimate the scattering cross sections for BC mobility diameters of 155, 245, and 320 nm, because of uncertainties associated with theoretical calculations for small particles as wellmore » as laboratory scattering measurements. The measured optical cross sections for coated BC by sulfuric acid and for those undergoing further hygroscopic growth are captured by theoretical calculations using a concentric core-shell structure, with differences of less than 20 %. This suggests that the core-shell shape represents the realistic BC coating morphology reasonably well in this case, which is consistent with the observed strong structure compaction during aging. We find that the absorption and scattering properties of fresh BC aggregates vary by up to 60 % due to uncertainty in the BC refractive index, which, however, is a factor of two smaller in the case of coated BC particles. Sensitivity analyses on the BC morphology show that the optical properties of fresh BC aggregates are more sensitive to fractal dimension than primary spherule size. The absorption and scattering cross sections of coated BC particles vary by more than a factor of two due to different coating structures. We find an increase of 20–250 % in absorption and a factor of 3–15 in scattering during aging, significantly depending on coating morphology and aging stages. Applying the aging model to CalNex 2010 field measurements, we show that the resulting BC direct radiative forcing (DRF) first increases from 1.5 to 1.7 W m-2 and subsequently decreases to 1.0 W m-2 during the transport from the Los Angeles Basin to downwind regions, as a result of the competition between absorption enhancement due to coating and dilution of BC concentration. The BC DRF can vary by up to a factor of two due to differences in BC coating morphology. Thus, an accurate estimate of BC DRF requires the incorporation of a dynamic BC aging process that accounts for realistic morphology in climate models, particularly for the regional analysis with high atmospheric heterogeneity.« less

  1. The ? Andromedae system: new constraints on the companion mass, system age, and further multiplicity

    SciTech Connect (OSTI)

    Hinkley, Sasha; David, Trevor; Hillenbrand, Lynne A.; Pueyo, Laurent; Faherty, Jacqueline K.; Oppenheimer, Ben R.; Brenner, Douglas; Veicht, Aaron; Nilsson, Ricky; Mamajek, Eric E.; Kraus, Adam L.; Rice, Emily L.; Ireland, Michael J.; Vasisht, Gautam; Cady, Eric; Roberts, Jennifer E.; Zimmerman, Neil; Parry, Ian R.; Beichman, Charles; Dekany, Richard; and others

    2013-12-20

    ? Andromedae is a B9IVn star at 52 pc for which a faint substellar companion separated by 55 2 AU was recently announced. In this work, we present the first spectrum of the companion, '? And B,' using the Project 1640 high-contrast imaging platform. Comparison of our low-resolution YJH-band spectra to empirical brown dwarf spectra suggests an early-L spectral type. Fitting synthetic spectra from PHOENIX model atmospheres to our observed spectrum allows us to constrain the effective temperature to ?2000 K as well as place constraints on the companion surface gravity. Further, we use previously reported log(g) and T {sub eff} measurements of the host star to argue that the ? And system has an isochronal age of 220 100 Myr, older than the 30 Myr age reported previously. This interpretation of an older age is corroborated by the photometric properties of ? And B, which appear to be marginally inconsistent with other 10-100 Myr low-gravity L-dwarfs for the spectral type range we derive. In addition, we use Keck aperture masking interferometry combined with published radial velocity measurements to rule out the existence of any tight stellar companions to ? And A that might be responsible for the system's overluminosity. Further, we show that luminosity enhancements due to a nearly 'pole-on' viewing angle coupled with extremely rapid rotation is unlikely. ? And A is thus consistent with its slightly evolved luminosity class (IV), and we propose here that ? And, with a revised age of 220 100 Myr, is an interloper to the 30 Myr Columba association with which it was previously associated. The photometric and spectroscopic evidence for ? And B combined with our reassessment of the system age implies a substellar companion mass of 50{sub ?13}{sup +16} M {sub Jup}, consistent with a brown dwarf rather than a planetary-mass companion.

  2. Aging assessment of essential HVAC chillers used in nuclear power plants

    SciTech Connect (OSTI)

    Blahnik, D.E.; Camp, T.W.

    1996-09-01

    The Pacific Northwest Laboratory conducted a comprehensive aging assessment of chillers used in the essential safety air-conditioning systems in nuclear power plants (NPPs). The chillers used, and air-conditioning systems served, vary in design from plant to plant. The review of operating experience indicated that chillers experience aging degradation and failures. The primary aging factors of concern for chillers include vibration, excessive temperatures and pressures, thermal cycling, chemical attack, and poor quality cooling water. The evaluation of Licensee Event Reports (LERs) indicated that about 38% of the failures were primarily related to aging, 55% were partially aging related, and 7% of the failures were unassignable. About 25% of the failures were primarily caused by human, design, procedure, and other errors. The large number of errors is probably directly related to the complexity of chillers and their interfacing systems. Nearly all of the LERs were the result of entering plant Technical Specification Limiting Condition for Operation (LCO) that initiated remedial actions like plant shutdown procedures. The trend for chiller-related LERs has stabilized at about 0.13 LERs per plant year since 1988. Carefully following the vendor procedures and monitoring the equipment can help to minimize and/or eliminate most of the premature failures. Recording equipment performance can be useful for trending analysis. Periodic operation for a few hours on a weekly or monthly basis is useful to remove moisture and non-condensable gases that gradually build up inside the chiller. Chiller pressurization kits are available that will help minimize the amount of moisture and air ingress to low-pressure chillers during standby periods. The assessment of service life condition monitoring of chillers indicated there are many simple to sophisticated methods available that can help in chiller surveillance and monitoring.

  3. Nuclear power plant cable materials : review of qualification and currently available aging data for margin assessments in cable performance.

    SciTech Connect (OSTI)

    Celina, Mathias Christopher; Gillen, Kenneth Todd; Lindgren, Eric Richard

    2013-05-01

    A selective literature review was conducted to assess whether currently available accelerated aging and original qualification data could be used to establish operational margins for the continued use of cable insulation and jacketing materials in nuclear power plant environments. The materials are subject to chemical and physical degradation under extended radiationthermal- oxidative conditions. Of particular interest were the circumstances under which existing aging data could be used to predict whether aged materials should pass loss of coolant accident (LOCA) performance requirements. Original LOCA qualification testing usually involved accelerated aging simulations of the 40-year expected ambient aging conditions followed by a LOCA simulation. The accelerated aging simulations were conducted under rapid accelerated aging conditions that did not account for many of the known limitations in accelerated polymer aging and therefore did not correctly simulate actual aging conditions. These highly accelerated aging conditions resulted in insulation materials with mostlyinert' aging processes as well as jacket materials where oxidative damage dropped quickly away from the air-exposed outside jacket surface. Therefore, for most LOCA performance predictions, testing appears to have relied upon heterogeneous aging behavior with oxidation often limited to the exterior of the cable cross-section - a situation which is not comparable with the nearly homogenous oxidative aging that will occur over decades under low dose rate and low temperature plant conditions. The historical aging conditions are therefore insufficient to determine with reasonable confidence the remaining operational margins for these materials. This does not necessarily imply that the existing 40-year-old materials would fail if LOCA conditions occurred, but rather that unambiguous statements about the current aging state and anticipated LOCA performance cannot be provided based on original qualification testing data alone. The non-availability of conclusive predictions for the aging conditions of 40-year-old cables implies that the same levels of uncertainty will remain for any re-qualification or extended operation of these cables. The highly variable aging behavior of the range of materials employed also implies that simple, standardized aging tests are not sufficient to provide the required aging data and performance predictions for all materials. It is recommended that focused studies be conducted that would yield the material aging parameters needed to predict aging behaviors under low dose, low temperature plant equivalent conditions and that appropriately aged specimens be prepared that would mimic oxidatively-aged 40- to 60- year-old materials for confirmatory LOCA performance testing. This study concludes that it is not sufficient to expose materials to rapid, high radiation and high temperature levels with subsequent LOCA qualification testing in order to predictively quantify safety margins of existing infrastructure with regard to LOCA performance. We need to better understand how cable jacketing and insulation materials have degraded over decades of power plant operation and how this aging history relates to service life prediction and the performance of existing equipment to withstand a LOCA situation.

  4. Thermal Deactivation Mechanisms of Fully-Formed Lean NOx Trap Catalysts Aged by Lean/Rich Cycling

    Broader source: Energy.gov [DOE]

    Catalysts in fully formulated lean NOx traps are aged and evaluated in a bench-flow reactor using simulated diesel engine exhaust.

  5. The effects of changing exercise levels on weight and age-relatedweight gain

    SciTech Connect (OSTI)

    Williams, Paul T.; Wood, Peter D.

    2004-06-01

    To determine prospectively whether physical activity canprevent age-related weight gain and whether changing levels of activityaffect body weight. DESIGN/SUBJECTS: The study consisted of 8,080 maleand 4,871 female runners who completed two questionnaires an average(+/-standard deviation (s.d.)) of 3.20+/-2.30 and 2.59+/-2.17 yearsapart, respectively, as part of the National Runners' Health Study.RESULTS: Changes in running distance were inversely related to changes inmen's and women's body mass indices (BMIs) (slope+/-standard error(s.e.): -0.015+/-0.001 and -0.009+/-0.001 kg/m(2) per Deltakm/week,respectively), waist circumferences (-0.030+/-0.002 and -0.022+/-0.005 cmper Deltakm/week, respectively) and percent changes in body weight(-0.062+/-0.003 and -0.041+/-0.003 percent per Deltakm/week,respectively, all P<0.0001). The regression slopes were significantlysteeper (more negative) in men than women for DeltaBMI and Deltapercentbody weight (P<0.0001). A longer history of running diminishedthe impact of changing running distance on men's weights. When adjustedfor Deltakm/week, years of aging in men and years of aging in women wereassociated with increases of 0.066+/-0.005 and 0.056+/-0.006 kg/m(2) inBMI, respectively, increases of 0.294+/-0.019 and 0.279+/-0.028 percentin Delta percentbody weight, respectively, and increases of 0.203+/-0.016and 0.271+/-0.033 cm in waist circumference, respectively (allP<0.0001). These regression slopes suggest that vigorous exercise mayneed to increase 4.4 km/week annually in men and 6.2 km/week annually inwomen to compensate for the expected gain in weight associated with aging(2.7 and 3.9 km/week annually when correct for the attenuation due tomeasurement error). CONCLUSIONS: Age-related weight gain occurs evenamong the most active individuals when exercise is constant.Theoretically, vigorous exercise must increase significantly with age tocompensate for the expected gain in weight associated withaging.

  6. Thermal analysis of pentaerythritol tetranitrate and development of a powder aging model

    SciTech Connect (OSTI)

    Brown, Geoffrey W; Sandstrom, Mary M; Giambra, Anna M; Archuleta, Jose G; Monroe, Deirde C

    2009-01-01

    We have applied a range of different physical and thermal analysis techniques to characterize the thermal evolution of the specific surface area of pentaerythritol tetranitrate (PETN) powders. Using atomic force microscopy we have determined that the mass transfer mechanism leading to powder coarsening is probably sublimation and redeposition of PETN. Using thermogravimetric analysis we have measured vapor pressures of PETN powders whose aging will be simulated in future work. For one specific powder we have constructed an empirical model of the coarsening that is fit to specific surface area measurements at 60 C to 70 C to provide predictive capability of that powder's aging. Modulated differential scanning calorimetry and mass spectroscopy measurements highlight some of the thermal behavior of the powders and suggest that homologue-based eutectics and impurities are localized in the powder particles.

  7. Molecular ageing: Free radical initiated epimerization of thymopentin A case study

    SciTech Connect (OSTI)

    Sheykhkarimli, Dayag; Choo, Ken-Loon; Owen, Michael; Csizmadia, Imre G.; Fiser, Bla; Jjrt, Balzs; Viskolcz, Bla

    2014-05-28

    The epimerization of amino acid residues increases with age in living organisms. In the present study, the structural consequences and thermodynamic functions of the epimerization of thymopentin (TP-5), the active site of the thymic hormone thymopoietin, were studied using molecular dynamics and density functional theory methods. The results show that free radical-initiated D-amino acid formation is energetically favoured (?130 kJmol{sup ?1}) for each residue and induces significant changes to the peptide structure. In comparison to the wild-type (each residue in the L-configuration), the radius of gyration of the D-Asp{sup 3} epimer of the peptide decreased by 0.5 , and disrupted the intramolecular hydrogen bonding of the native peptide. Beyond establishing important structural, energetic and thermodynamic benchmarks and reference data for the structure of TP-5, these results disseminate the understanding of molecular ageing, the epimerization of amino acid residues.

  8. Effect of decontamination on aging processes and considerations for life extension

    SciTech Connect (OSTI)

    Diercks, D.R.

    1987-10-01

    The basis for a recently initiated program on the chemical decontamination of nuclear reactor components and the possible impact of decontamination on extended-life service is described. The incentives for extending plant life beyond the present 40-year limit are discussed, and the possible aging degradation processes that may be accentuated in extended-life service are described. Chemical decontamination processes for nuclear plant primary systems are summarized with respect to their corrosive effects on structural alloys, particularly those in the aged condition. Available experience with chemical cleaning processes for the secondary side of PWR steam generators is also briefly considered. Overall, no severe materials corrosion problems have been found that would preclude the use of these chemical processes, but concerns have been raised in several areas, particularly with respect to corrosion-related problems that may develop during extended service.

  9. Compact modeling of total ionizing dose and aging effects in MOS technologies

    SciTech Connect (OSTI)

    Esqueda, Ivan S.; Barnaby, Hugh J.; King, Michael Patrick

    2015-06-18

    This paper presents a physics-based compact modeling approach that incorporates the impact of total ionizing dose (TID) and stress-induced defects into simulations of metal-oxide-semiconductor (MOS) devices and integrated circuits (ICs). This approach utilizes calculations of surface potential (?s) to capture the charge contribution from oxide trapped charge and interface traps and to describe their impact on MOS electrostatics and device operating characteristics as a function of ionizing radiation exposure and aging effects. The modeling approach is demonstrated for bulk and silicon-on-insulator (SOI) MOS device. The formulation is verified using TCAD simulations and through the comparison of model calculations and experimental I-V characteristics from irradiated devices. The presented approach is suitable for modeling TID and aging effects in advanced MOS devices and ICs.

  10. Compact modeling of total ionizing dose and aging effects in MOS technologies

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Esqueda, Ivan S.; Barnaby, Hugh J.; King, Michael Patrick

    2015-06-18

    This paper presents a physics-based compact modeling approach that incorporates the impact of total ionizing dose (TID) and stress-induced defects into simulations of metal-oxide-semiconductor (MOS) devices and integrated circuits (ICs). This approach utilizes calculations of surface potential (ψs) to capture the charge contribution from oxide trapped charge and interface traps and to describe their impact on MOS electrostatics and device operating characteristics as a function of ionizing radiation exposure and aging effects. The modeling approach is demonstrated for bulk and silicon-on-insulator (SOI) MOS device. The formulation is verified using TCAD simulations and through the comparison of model calculations and experimentalmore » I-V characteristics from irradiated devices. The presented approach is suitable for modeling TID and aging effects in advanced MOS devices and ICs.« less

  11. Electrochemical aging of humectant-treated thermal-sprayed zinc anodes for cathodic protection

    SciTech Connect (OSTI)

    Covino, B.S. Jr.; Holcomb, G.R.; Bullard, S.J.; Russell, J.H.; Cramer, S.D.; Bennett, J.E.; Laylor, H.M.

    1999-07-01

    Humectants, substances that promote the retention of moisture, were studied to determine their effectiveness in improving the performance and extending the service life of both new and previously-aged thermal-sprayed Zn anodes used in impressed current (ICCP) and galvanic cathodic protection (GCP) systems for steel-reinforced concrete structures. Potassium acetate, lithium nitrate, and lithium bromide were applied to a series of thermal-sprayed Zn-coated concrete slabs before starting the ICCP or GCP experiment. All of the humectants altered the behavior of the thermal-sprayed Zn anodes. LiNO{sub 3} was the most beneficial for ICCP anodes and LiBr was the most beneficial for GCP anodes. Circuit resistances for ICCP anodes and galvanic current density for GCP anodes are compared on the basis of electrochemical aging, humidity, and type of humectant.

  12. A Vital Legacy: Biological and Environmental Research in the Atomic Age

    DOE R&D Accomplishments [OSTI]

    1997-09-01

    This booklet presents a summary of the five decades of biological and environmental research in the atomic age. It commemorates the contributions to science and society during these decades and concludes with a view to the years ahead. The Contents includes Safety First: in the Shadow of a New Technology; A Healthy Citizenry: Gifts of the New Era; and Environmental Concerns: From Meteorology to Ecology. The conclusion is titled An Enduring Mandate: Looking to the Future.

  13. A vital legacy: Biological and environmental research in the atomic age

    SciTech Connect (OSTI)

    Vaughan, D.

    1997-09-01

    This booklet presents a summary of the five decades of biological and environmental research in the atomic age. It commemorates the contributions to science and society during these decades and concludes with a view to the years ahead. The Contents includes `Safety First: in the Shadow of a New Technology; A Healthy Citizenry: Gifts of the New Era; and Environmental Concerns: From Meteorology to Ecology`. The conclusion is titled `An Enduring Mandate: Looking to the Future`.

  14. Figure 2. Stratigraphic Summary of Ages, Names and Rock Types in the ANWR

    U.S. Energy Information Administration (EIA) Indexed Site

    1002 2. Stratigraphic Summary of Ages, Names and Rock Types in the ANWR 1002 and Coastal Plain Area of the Alaska North Slope. Potentially Productive Reservoirs and Plays Assessed by the USGS are Indicated fig2.jpg (30091 bytes) Source: Edited from U.S. Geological Survey, "The Oil and Gas Resource Potential of the Arctic National Wildlife Refuge 1002 Area, Alaska," Open File Report 98-34, 1999.

  15. LWR Sustainability: Assessment of Aging of Nuclear Power Plant Safety Related Concrete Strutures

    SciTech Connect (OSTI)

    Graves III, Herman; Naus, Dan J

    2013-01-01

    Current regulatory testing and inspection requirements are reviewed and a summary of degradation experience is presented. Techniques commonly used to inspect NPP concrete structures to assess and quantify age-related degradation are summarized. An approach for conduct of condition assessments of structures in NPPs is presented. Criteria, based primarily on visual indications, are provided for use in classification and assessment of concrete degradation. Materials and techniques for repair of degraded structures are generally discussed.

  16. 3 Million Square Feet of Aging Nuclear Weapons Buildings Torn Down |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    National Nuclear Security Administration 3 Million Square Feet of Aging Nuclear Weapons Buildings Torn Down August 13, 2008 Agency Passes Goal One Year Early WASHINGTON, DC - Three million square feet of old buildings, many from the earliest days of the Cold War, have been torn down across the eight sites that make up the National Nuclear Security Administration's (NNSA's) national security complex. This accomplishment, achieved a year early, will allow NNSA to be more efficient in meeting

  17. CP-1 Anniversary: Nuclear Pioneers Remember the Dawn of the Nuclear Age |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Argonne National Laboratory Anniversary: Nuclear Pioneers Remember the Dawn of the Nuclear Age Share Topic Energy Energy sources Nuclear energy On December 2, 1942, 49 scientists, led by Enrico Fermi, made history when Chicago Pile 1 went critical and produced the world's first self-sustaining, controlled nuclear chain reaction. Seventy years later, two of the last surviving CP-1 pioneers, Harold Agnew and Warren Nyer, recall that historic day

  18. Aging and Phase Stability Studies of Alloy 22 FY08 Final Report

    SciTech Connect (OSTI)

    Torres, S G

    2008-04-03

    This report is a compilation of work done over the past ten years in support of phase stability studies of Alloy 22 for the Yucca Mountain Project and contains information previously published, reported, and referenced. Most sections are paraphrased here for the convenience of readers. Evaluation of the fabrication processes involved in the manufacture of waste containers is important as these processes can have an effect on the metallurgical structure of an alloy. Because material properties such as strength, toughness, aging kinetics and corrosion resistance are all dependent on the microstructure, it is important that prototypes be built and evaluated for processing effects on the performance of the material. Of particular importance are welds, which have an as-cast microstructure with chemical segregation and precipitation of complex phases resulting from the welding process. The work summarized in this report contains information on the effects of fabrication processes such as solution annealing, stress mitigation, heat-to-heat variability, and welding on the kinetics of precipitation, mechanical, and corrosion properties. For a waste package lifetime of thousands of years, it is impossible to test directly in the laboratory the behavior of Alloy 22 under expected repository conditions. The changes that may occur in these materials must be accelerated. For phase stability studies, this is achieved by accelerating the phase transformations by increasing test temperatures above those anticipated in the proposed repository. For these reasons, Alloy 22 characterization specimens were aged at Lawrence Livermore National Laboratory (LLNL) Aging Facilities for times from 1 hour up to 8 years at temperatures ranging from 200-750 C. These data as well as the data from specimens aged at 260 C, 343 C, and 427 C for 100,028 hours at Haynes International will be used for performance confirmation and model validation.

  19. CABLE AGING AND CONDITION MONITORING OF RADIATION RESISTANT NANO-DIELECTRICS IN ADVANCED REACTOR APPLICATIONS

    SciTech Connect (OSTI)

    Duckworth, Robert C; Aytug, Tolga; Paranthaman, Mariappan Parans; Kidder, Michelle; Polyzos, Georgios; Leonard, Keith J

    2015-01-01

    Cross-linked polyethylene (XLPE) nanocomposites have been developed in an effort to improve cable insulation lifetime to serve in both instrument cables and auxiliary power systems in advanced reactor applications as well as to provide an alternative for new or retro-fit cable insulation installations. Nano-dielectrics composed of different weight percentages of MgO & SiO2 have been subjected to radiation at accumulated doses approaching 20 MRad and thermal aging temperatures exceeding 100 C. Depending on the composition, the performance of the nanodielectric insulation was influenced, both positively and negatively, when quantified with respect to its electrical and mechanical properties. For virgin unradiated or thermally aged- samples, XLPE nanocomposites with 1wt.% SiO2 showed improvement in breakdown strength and reduction in its dissipation factor when compared to pure undoped- XLPE, while XLPE 3wt.% SiO2 resulted in lower breakdown strength. When aged in air at 120 C, retention of electrical breakdown strength and dissipation factor was observed for XLPE 3wt.% MgO nanocomposites. Irrespective of the nanoparticle species, XLPE nanocomposites that were gamma irradiated up to the accumulated dose of 18 MRad showed a significant drop in breakdown strength especially for particle concentrations greater than 3 wt.%. Additional attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy measurements suggest changes in the structure of the XLPE SiO2 nanocomposites associated with the interaction of silicon and oxygen. Discussion on the relevance of property changes with respect to cable aging and condition monitoring is presented.

  20. Fatigue and Creep Crack Propagation behaviour of Alloy 617 in the Annealed and Aged Conditions

    SciTech Connect (OSTI)

    Julian K. Benz; Richard N. Wright

    2013-10-01

    The crack propagation behaviour of Alloy 617 was studied under various conditions. Elevated temperature fatigue and creep-fatigue crack growth experiments were conducted at 650 and 800 degrees C under constant stress intensity (triangle K) conditions and triangular or trapezoidal waveforms at various frequencies on as-received, aged, and carburized material. Environmental conditions included both laboratory air and characteristic VHTR impure helium. As-received Alloy 617 displayed an increase in the crack growth rate (da/dN) as the frequency was decreased in air which indicated a time-dependent contribution component in fatigue crack propagation. Material aged at 650°C did not display any influence on the fatigue crack growth rates nor the increasing trend of crack growth rate with decreasing frequency even though significant microstructural evolution, including y’ (Ni3Al) after short times, occurred during aging. In contrast, carburized Alloy 617 showed an increase in crack growth rates at all frequencies tested compared to the material in the standard annealed condition. Crack growth studies under quasi-constant K (i.e. creep) conditions were also completed at 650 degrees C and a stress intensity of K = 40 MPa9 (square root)m. The results indicate that crack growth is primarily intergranular and increased creep crack growth rates exist in the impure helium environment when compared to the results in laboratory air. Furthermore, the propagation rates (da/dt) continually increased for the duration of the creep crack growth either due to material aging or evolution of a crack tip creep zone. Finally, fatigue crack propagation tests at 800 degrees C on annealed Alloy 617 indicated that crack propagation rates were higher in air than impure helium at the largest frequencies and lowest stress intensities. The rates in helium, however, eventually surpass the rates in air as the frequency is reduced and the stress intensity is decreased which was not observed at 650 degrees C.

  1. Evolution of Microstructure in a Nickel-based Superalloy as a Function of Ageing Time

    SciTech Connect (OSTI)

    Chen, Wei-Ren; Smith, Gregory Scott; Porcar, L.; Liaw, Peter K; Kai, Ji-Jung; Ren, Yang

    2011-01-01

    An experimental investigation, combining synchrotron X-ray powder diffraction, small-angle neutron-scattering, and transmission electron microscopy, has been undertaken to study the microstructure of nanoprecipitates in a nickel-based superalloy. Upon increasing the ageing time during a heat-treatment process, the average size of the precipitates first decreases before changing to a monotonical growth stage. Possible reasons for this observed structural evolution, which is predicted thermodynamically, are suggested.

  2. Delamination Failures in Long-Term Field Aged PV Modules from Point of View

    Broader source: Energy.gov (indexed) [DOE]

    Dehumidifiers -- v3.0 More Documents & Publications Beverage Vending Machines Metal Halide Lamp Ballasts and Fixtures Residential Dishwashers of Encapsulant | Department of Energy

    PowerPoint presentation was originally given by Tsuyoshi Shioda of Mitsui Chemicals, Inc. on Feb. 26, 2014 during the opening session of the 2013 NREL PV Module Reliability Workshop. It summarizes the study of long-term, field-aged photovoltaic modules with typical delamination failures from the point of

  3. Precipitation in a Cu–Cr–Zr–Mg alloy during aging

    SciTech Connect (OSTI)

    Cheng, J.Y. Shen, B.; Yu, F.X.

    2013-07-15

    The precipitation processes in a Cu-0.69Cr-0.10Zr-0.02Mg alloy aged at 450 °C and 550 °C have been investigated by transmission electron microscopy and high resolution transmission electron microscopy. The precipitation sequence in this alloy aged at 450 °C is: supersaturated solid solution → Guinier–Preston zone (fcc Cr-rich phase) → ordered fcc Cr-rich phase → ordered bcc Cr-rich phase. The precipitation sequence in this alloy aged at 550 °C is: supersaturated solid solution → ordered fcc Cr-rich phase → ordered bcc Cr-rich phase. In the evolution of decomposition, the orientation relationship between the precipitates and the Cu matrix changes from cube-on-cube to Nishiyama–Wassermann orientation. The ordering of Cr-rich precipitates facilitates the formation of the bcc precipitates and promotes the development of Nishiyama–Wassermann orientation. - Highlights: • Two different precipitation sequences in the Cu–Cr–Zr–Mg alloy are proposed. • The changes in orientation relationship of the precipitates are presented. • The roles of ordering and coherent interface of the precipitates are discussed.

  4. Excitation-emission spectra and fluorescence quantum yields for fresh and aged biogenic secondary organic aerosols

    SciTech Connect (OSTI)

    Lee, Hyun Ji; Laskin, Alexander; Laskin, Julia; Nizkorodov, Sergey A.

    2013-05-10

    Certain biogenic secondary organic aerosols (SOA) become absorbent and fluorescent when exposed to reduced nitrogen compounds such as ammonia, amines and their salts. Fluorescent SOA may potentially be mistaken for biological particles by detection methods relying on fluorescence. This work quantifies the spectral distribution and effective quantum yields of fluorescence of SOA generated from two monoterpenes, limonene and a-pinene, and two different oxidants, ozone (O3) and hydroxyl radical (OH). The SOA was generated in a smog chamber, collected on substrates, and aged by exposure to ~100 ppb ammonia vapor in air saturated with water vapor. Absorption and excitation-emission matrix (EEM) spectra of aqueous extracts of aged and control SOA samples were measured, and the effective absorption coefficients and fluorescence quantum yields (~0.005 for 349 nm excitation) were determined from the data. The strongest fluorescence for the limonene-derived SOA was observed for excitation = 420+- 50 nm and emission = 475 +- 38 nm. The window of the strongest fluorescence shifted to excitation = 320 +- 25 nm and emission = 425 +- 38 nm for the a-pinene-derived SOA. Both regions overlap with the excitation-emission matrix (EEM) spectra of some of the fluorophores found in primary biological aerosols. Our study suggests that, despite the low quantum yield, the aged SOA particles should have sufficient fluorescence intensities to interfere with the fluorescence detection of common bioaerosols.

  5. Precipitation kinetics during aging of an alumina-forming austenitic stainless steel

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Trotter, Geneva; Hu, Bin; Sun, Annie Y.; Harder, Reed; Miller, Michael K.; Baker, Ian; Yao, Lan

    2016-04-28

    The microstructural evolution of DAFA26, an alumina-forming austenitic (AFA) stainless steel, was investigated during aging. The effect of aging at 750 °C and 800 °C on the growth of spherical γ’-Ni3(Al, Ti) particles present in the as-processed state was studied extensively using X-ray diffraction, microhardness testing, scanning electron microscopy, transmission electron microscopy, and atom probe tomography. The γ’ particles had a cube-on-cube orientation relationship with the matrix (i.e. ((010)(010)m//(010)(010)p, [100][100]m//[100][100]p)). The coarsening kinetics of γ’-Ni3Al particles were in agreement with the Lifshitz, Slyozof-Wagner theory. Coarse Laves phase particles were also present in the as-processed state, and during the aging processmore » both smaller Laves phase precipitates and B2-NiAl precipitates formed on both the grain boundaries and in the matrix. As a result, the γ’ precipitates were determined to have the most impact on the room temperature hardness.« less

  6. Effects of thyroid hormone on. beta. -adrenergic responsiveness of aging cardiovascular systems

    SciTech Connect (OSTI)

    Tsujimoto, G.; Hashimoto, K.; Hoffman, B.B.

    1987-03-01

    The authors have compared the effects of ..beta..-adrenergic stimulation on the heart and peripheral vasculature of young (2-mo-old) and older (12-mo-old) rats both in the presence and absence of triiodothyronine (T/sub 3/)-induced hyperthyroidism. The hemodynamic consequences of T/sub 3/ treatment were less prominent in the aged hyperthyroid rats compared with young hyperthyroid rats (both in intact and pithed rats). There was a decrease in sensitivity of chronotropic responsiveness to isoproterenol in older pithed rats, which was apparently reversed by T/sub 3/ treatment. The number and affinity of myocardial ..beta..-adrenergic receptor sites measured by (/sup 125/I)cyanopindolol were not significantly different in young and older control rats; also, ..beta..-receptor density increased to a similar extent in both young and older T/sub 3/-treated rats. The ability of isoproterenol to relax mesenteric arterial rings, markedly blunted in older rats, was partially restored by T/sub 3/ treatment without their being any change in isoproterenol-mediated relaxation in the arterial preparation from young rats. The number and affinity of the ..beta..-adrenergic receptors measured in the mesenteric arteries was unaffected by either aging or T/sub 3/ treatment. The data suggest that effects of thyroid hormone and age-related alterations of cardiovascular responsiveness to ..beta..-adrenergic stimulation are interrelated in a complex fashion with a net result that the hyperkinetic cardiovascular manifestations in hyperthyroidism are attenuated in the older animals.

  7. Atomic structure of Cu-10. 9 at % Be alloys in the early stages of aging

    SciTech Connect (OSTI)

    Koo, Y.M.

    1987-01-01

    Diffuse x-ray scattering was employed to investigate the local atomic structure and static strains in a single crystal of a Cu-10.9 at. % Be alloy in the early stages of aging. In addition to these experiments, neutron elastic and inelastic scattering were obtained to investigate the phonon properties in the as-quenched state of this alloy. In the as-quenched state, there is a nearly regular array of small ellipsoidal Be clusters aligned along <100> directions (This produces the tweed contrast seen in TEM). The density of these clusters is 7.5 x 10/sup 26//m/sup 3/. The diffuse streaks seen in electron diffraction patterns are due largely to thermal diffuse scattering. Phonon-dispersion curves show no large differences from those of pure copper, except at (xi xi xi)/sub T/ zone boundary, where there is softening. This difference may be due to a Kohn anomaly. The elastic anisotropy of this alloy increases considerably with alloying, which probably leads to the plate-like GP zone morphology in subsequent aging treatments. The structure of the GP zones is a mixture of Be-rich single- and multi-layered zones. As aging proceeds, the zones grow in thickness.

  8. Modeling tracers of young stellar population age in star-forming galaxies

    SciTech Connect (OSTI)

    Levesque, Emily M.; Leitherer, Claus

    2013-12-20

    The young stellar population of a star-forming galaxy is the primary engine driving its radiative properties. As a result, the age of a galaxy's youngest generation of stars is critical for a detailed understanding of its star formation history, stellar content, and evolutionary state. Here we present predicted equivalent widths for the H?, H?, and Br? recombination lines as a function of stellar population age. The equivalent widths are produced by the latest generations of stellar evolutionary tracks and the Starburst99 stellar population synthesis code, and are the first to fully account for the combined effects of both nebular emission and continuum absorption produced by the synthetic stellar population. Our grid of model stellar populations spans six metallicities (0.001 < Z < 0.04), two treatments of star formation history (a 10{sup 6} M {sub ?} instantaneous burst and a continuous star formation rate of 1 M {sub ?} yr{sup 1}), and two different treatments of initial rotation rate (v {sub rot} = 0.0v {sub crit} and 0.4v {sub crit}). We also investigate the effects of varying the initial mass function. Given constraints on galaxy metallicity, our predicted equivalent widths can be applied to observations of star-forming galaxies to approximate the age of their young stellar populations.

  9. Aging effects in palladium and LaNi{sub 4.25}Al{sub 0.75} tritides

    SciTech Connect (OSTI)

    Nobile, A.; Wermer, J.R.; Walters, R.T.

    1991-12-31

    Palladium and LaNi{sub 5-x}Al{sub x} (x=0.30, 0.75, 0.85), which form reversible hydrides, are used for tritium processing and storage in the Savannah River Site (SRS) tritium facilities. As part of a program to develop technology based on the use of reversible metal hydrides for tritium processing and storage, the effects of aging on the thermodynamic behavior of palladium and LaNi{sub 4.25}Al{sub 0. 75} tritides are under investigation. During aging, the {sup 3}He tritium decay product remains in the tritide lattice and changes the thermodynamics of the tritium-metal tritide system. Aging effects in 755-day-aged palladium and 1423-day-aged LaNi{sub 4.25}Al{sub 0.75} tritides will be reported. Changes in the thermodynamics were determined by measuring tritium desorption isotherms on aging samples. In palladium, aging decreases the desorption isotherm plateau pressure and changes the {alpha}-phase portion of the isotherm. Aging-induced changes in desorption isotherms are more drastic in LaNi{sub 4.25}Al{sub 0.75}. Among the changes noted are: (1) decreased isotherm plateau pressure, (2) increased isotherm plateau slope, and (3) appearance of deep-trapped tritium, removable only by exchange with deuterium.

  10. Leaching of BTEX from Aged Crude Oil Contaminated Model Soils: Experimental and Modeling Results

    SciTech Connect (OSTI)

    Huesemann, Michael H.; Hausmann, Tom S.; Fortman, Timothy J.

    2005-01-01

    It is generally assumed that soil properties such as organic matter content, porosity, and mineral surface area have a significant effect on the bioavailability and leachability of aged petroleum hydrocarbons. In order to test this hypothesis, nine model soils or sorbents (i.e., fine and coarse quartz sand, montmorillonite and kaolinite clay, peat, 60? and 150? silica gel, a loam soil, and non-porous glass beads) were spiked with a crude oil, aged for 27 months in the laboratory, and transferred to glass columns for the performance of continuous flow leaching experiments. The column effluents were periodically sampled for 43 days and analyzed for BTEX. A one-dimensional flow model for predicting the dissolution and dispersion of individual hydrocarbons from a multi-component NAPL such as crude oil was used to fit the leaching data (i.e., the BTEX concentration versus time curves) by adjusting the equilibrium oil-leachate partitioning coefficient (Kol) for each respective hydrocarbon. The Peclet number, which is a measure of dispersion and a required modeling parameter, was measured in separate chloride tracer experiments for each soil column. Results demonstrate that soil properties did not significantly affect the leaching kinetics of BTEX from the columns. Instead, BTEX leaching curves could be successfully fitted with the one-dimensional NAPL dissolution flow model for all sorbents with the exception of montmorillonite clay. The fitting parameter Kol for each hydrocarbon was found to be similar to the Kol values that were independently measured for the same crude oil by Rixey et al. (Journal of Hazardous Materials B, 65: 137-156, 1999). In addition, the fitted Kol values were very similar for BTEX leaching from aged compared to freshly spiked loam soil. These findings indicate that leaching of BTEX in the aged soils that are contaminated with crude oil at the high concentrations commonly found in the environment (i.e., >20,000 mg/kg) was not affected by soil properties or aging but rather was governed by the equilibrium dissolution of these hydrocarbons from the crude oil NAPL that is coating the soil particles.

  11. Variation of the radiative properties during black carbon aging: theoretical and experimental intercomparison

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    He, C.; Liou, K.-N.; Takano, Y.; Zhang, R.; Levy Zamora, M.; Yang, P.; Li, Q.; Leung, L. R.

    2015-10-28

    A theoretical black carbon (BC) aging model is developed to account for three typical evolution stages, namely, freshly emitted aggregates, BC coated by soluble material, and BC particles undergoing further hygroscopic growth. The geometric-optics surface-wave (GOS) approach is employed to compute the BC single-scattering properties at each aging stage, which are subsequently compared with laboratory measurements. Theoretical calculations are consistent with measurements in extinction and absorption cross sections for fresh BC aggregates with different BC sizes (i.e., mobility diameters of 155, 245, and 320 nm), with differences of ≤ 25 %. The measured optical cross sections for BC coated bymore » sulfuric acid and for that undergoing further hygroscopic growth are generally captured (differences < 30 %) by theoretical calculations using a concentric core-shell structure, with an overestimate in extinction and absorption of the smallest BC size and an underestimate in scattering of the largest BC size. We find that the absorption and scattering cross sections of fresh BC aggregates vary by 20–40 and 50–65 %, respectively, due to the use of upper (1.95–0.79i) and lower (1.75–0.63i) bounds of BC refractive index, while the variations are < 20 % in absorption and < 50 % in scattering in the case of coated BC particles. Sensitivity analyses of the BC morphology show that the optical properties of fresh BC aggregates are more sensitive to fractal dimension than primary spherule size. The absorption and scattering cross sections of coated BC particles vary by more than a factor of 2 due to different coating structures. We find an increase of 20–250 % in absorption and a factor of 3–15 in scattering during aging, significantly depending on coating morphology and aging stages. This study suggests that an accurate estimate of BC radiative effects requires the incorporation of a dynamic BC aging process that accounts for realistic coating structures in climate models.« less

  12. Exposure to mercury among Spanish preschool children: Trend from birth to age four

    SciTech Connect (OSTI)

    Llop, Sabrina; Murcia, Mario; Aguinagalde, Xabier; Vioque, Jesus; Rebagliato, Marisa; Iñiguez, Carmen; Lopez-Espinosa, Maria-Jose; Amurrio, Ascensión; María Navarrete-Muñoz, Eva; and others

    2014-07-15

    The purpose of this study is to describe the total hair mercury concentrations and their determinants in preschool Spanish children, as well as to explore the trend in mercury exposure from birth to the age four. This evolution has been scarcely studied in other birth cohort studies. The study population was 580 four year old children participating in the INMA (i.e. Childhood and Environment) birth cohort study in Valencia (2008–2009). Total mercury concentration at age four was measured in hair samples by atomic absorption spectrometry. Fish consumption and other covariates were obtained by questionnaire. Multivariate linear regression models were conducted in order to explore the association between mercury exposure and fish consumption, socio-demographic characteristics and prenatal exposure to mercury. The geometric mean was 1.10 µg/g (95%CI: 1.02, 1.19). Nineteen percent of children had mercury concentrations above the equivalent to the Provisional Tolerable Weekly Intake proposed by WHO. Mercury concentration was associated with increasing maternal age, fish consumption and cord blood mercury levels, as well as decreasing parity. Children whose mothers worked had higher mercury levels than those with non working mothers. Swordfish, lean fish and canned fish were the fish categories most associated with hair mercury concentrations. We observed a decreasing trend in mercury concentrations between birth and age four. In conclusion, the children participating in this study had high hair mercury concentrations compared to reported studies on children from other European countries and similar to other countries with high fish consumption. The INMA study design allows the evaluation of the exposure to mercury longitudinally and enables this information to be used for biomonitoring purposes and dietary recommendations. - Highlights: • The geometric mean of hair Hg concentrations was 1.10 µg/g. • 19% of children had Hg concentrations above the RfD proposed by the WHO. • Hair Hg concentrations in children increased as a function of total fish intake. • Swordfish, lean fish and canned fish were the most related to Hg concentrations. • There was a decrease in Hg concentrations from birth to age four.

  13. Aging Management Guideline for commercial nuclear power plants: Battery chargers, inverters and uninterruptible power supplies. Final report

    SciTech Connect (OSTI)

    Berg, R.; Stroinski, M.; Giachetti, R.

    1994-02-01

    This Aging Management Guideline (AMG) describes recommended methods for effective detection and mitigation of age-related degradation mechanisms in BWR and PWR commercial nuclear power plant battery chargers, inverters and uninterruptible power supplies important to license renewal. The intent of this AMG is to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR Part 54. This AMG is presented in a manner that allows personnel responsible for performance analysis and maintenance to compare their plant-specific aging mechanisms (expected or already, experienced) and aging management program activities to the more generic results and recommendations presented herein.

  14. Methodology for the Incorporation of Passive Component Aging Modeling into the RAVEN/ RELAP-7 Environment

    SciTech Connect (OSTI)

    Mandelli, Diego; Rabiti, Cristian; Cogliati, Joshua; Alfonsi, Andrea; Askin Guler; Tunc Aldemir

    2014-11-01

    Passive system, structure and components (SSCs) will degrade over their operation life and this degradation may cause to reduction in the safety margins of a nuclear power plant. In traditional probabilistic risk assessment (PRA) using the event-tree/fault-tree methodology, passive SSC failure rates are generally based on generic plant failure data and the true state of a specific plant is not reflected realistically. To address aging effects of passive SSCs in the traditional PRA methodology [1] does consider physics based models that account for the operating conditions in the plant, however, [1] does not include effects of surveillance/inspection. This paper represents an overall methodology for the incorporation of aging modeling of passive components into the RAVEN/RELAP-7 environment which provides a framework for performing dynamic PRA. Dynamic PRA allows consideration of both epistemic and aleatory uncertainties (including those associated with maintenance activities) in a consistent phenomenological and probabilistic framework and is often needed when there is complex process/hardware/software/firmware/ human interaction [2]. Dynamic PRA has gained attention recently due to difficulties in the traditional PRA modeling of aging effects of passive components using physics based models and also in the modeling of digital instrumentation and control systems. RAVEN (Reactor Analysis and Virtual control Environment) [3] is a software package under development at the Idaho National Laboratory (INL) as an online control logic driver and post-processing tool. It is coupled to the plant transient code RELAP-7 (Reactor Excursion and Leak Analysis Program) also currently under development at INL [3], as well as RELAP 5 [4]. The overall methodology aims to: • Address multiple aging mechanisms involving large number of components in a computational feasible manner where sequencing of events is conditioned on the physical conditions predicted in a simulation environment such as RELAP-7. • Identify the risk-significant passive components, their failure modes and anticipated rates of degradation • Incorporate surveillance and maintenance activities and their effects into the plant state and into component aging progress. • Asses aging affects in a dynamic simulation environment 1. C. L. SMITH, V. N. SHAH, T. KAO, G. APOSTOLAKIS, “Incorporating Ageing Effects into Probabilistic Risk Assessment –A Feasibility Study Utilizing Reliability Physics Models,” NUREG/CR-5632, USNRC, (2001). 2. T. ALDEMIR, “A Survey of Dynamic Methodologies for Probabilistic Safety Assessment of Nuclear Power Plants, Annals of Nuclear Energy, 52, 113-124, (2013). 3. C. RABITI, A. ALFONSI, J. COGLIATI, D. MANDELLI and R. KINOSHITA “Reactor Analysis and Virtual Control Environment (RAVEN) FY12 Report,” INL/EXT-12-27351, (2012). 4. D. ANDERS et.al, "RELAP-7 Level 2 Milestone Report: Demonstration of a Steady State Single Phase PWR Simulation with RELAP-7," INL/EXT-12-25924, (2012).

  15. Geologic ages and accumulation rates of basalt-flow groups and sedimentary interbeds in selected wells at the Idaho National Engineering Laboratory, Idaho

    SciTech Connect (OSTI)

    Anderson, S.R.; Liszewski, M.J.; Cecil, L.D.

    1997-01-01

    Geologic ages and accumulation rates, estimated from regressions, were used to evaluate measured ages and interpreted stratigraphic and structural relations of basalt and sediment in the unsaturated zone and the Snake River Plain aquifer at the Idaho National Engineering Laboratory (INEL) in eastern Idaho. Geologic ages and accumulation rates were estimated from standard linear regressions of 21 mean potassium-argon (K-Ar) ages, selected mean paleomagnetic ages, and cumulative depths of a composite stratigraphic section composed of complete intervals of basalt and sediment that were deposited in areas of past maximum subsidence. Accumulation rates also were estimated from regressions of stratigraphic intervals in three wells in and adjacent to an area of interpreted uplift at and near the Idaho Chemical Processing Plant (ICPP) and the Test Reactor Area (TRA) to allow a comparison of rates in areas of past uplift and subsidence. Estimated geologic ages range from about 200 thousand to 1.8 million years before present and are reasonable approximations for the interval of basalt and sediment above the effective base of the aquifer, based on reported uncertainties of corresponding measured ages. Estimated ages between 200 and 800 thousand years are within the range of reported uncertainties for all 15 K-Ar ages used in regressions and two out of three -argon ({sup 40}Ar/{sup 39}Ar) ages of duplicate argon samples. Two sets of estimated ages between 800 thousand and 1.8 million years are within the range of reported uncertainties for all seven K-Ar ages used in regressions, which include one shared age of about 800 thousand years. Two sets of ages were estimated for this interval because K-Ar ages make up two populations that agree with previous and revised ages of three paleomagnetic subchrons. The youngest set of ages is consistent with a K-Ar age from the effective base of the aquifer that agrees with previous ages of the Olduvai Normal-Polarity Subchron.

  16. PBX 9404 detonation copper cylinder tests: a comparison of new and aged material

    SciTech Connect (OSTI)

    Hill, Larry G [Los Alamos National Laboratory; Mier, Robert [Los Alamos National Laboratory; Briggs, Matthew E [Los Alamos National Laboratory

    2009-01-01

    We present detonation copper cylinder test results on aged PBX 9404 (94 wt% HMX, 3 wt% CEF, 2.9 wt% NC, 0.1 wt% DPA) explosive. The charges were newly pressed from 37.5 year-old molding powder. We compare these results to equivalent data performed on the same lot when it was 3.5 years old. Comparison of the detonation energy inferred from detonation speed to that inferred from wall motion suggests that the HMX energy is unchanged but the NC energy has decreased to {approx}25% of its original value. The degradation of explosives and their binders is a subject of continual interest. Secondary explosives such as HMX are sufficiently stable near room temperature that they do not measurably degrade over a period of at least several decades. For formulated systems the bigger concern is binder degradation, for which the three main issues are strength, initiation safety, and (if the binder is energetic) energy content. In this paper we examine the detonation energy of new and aged PBX 9404 (94 wt% HMX, 3 wt% tris-{beta} chloroethylphosphate (CEF), 2.9 wt% nitrocellulose (NC), 0.1 wt% diphenylamine (DPA) [1, 2]), measured via the detonation copper cylinder test. In 1959, two independent PBX 9404 accidents [3] raised serious concerns about the safety of the formulation. Over about a decade's time, Los Alamos pursued a safer, energetically equivalent replacement, which ultimately became PBX 9501. In order to accurately compare the performance of the PBX 9404 and PBX 9501 formulations, W. Campbell and R. Engelke (C & E) developed a stringent cylinder test protocol that they called the Los Alamos Precision Cylinder Test [4]. The present aging study is possible because excellent PBX 9404 data from those qualification tests endures.

  17. INTERMEDIATE-AGE STELLAR POPULATIONS IN CLASSICAL QUASI-STELLAR OBJECT HOST GALAXIES

    SciTech Connect (OSTI)

    Canalizo, Gabriela; Stockton, Alan E-mail: stockton@ifa.hawaii.edu

    2013-08-01

    Although mergers and starbursts are often invoked in the discussion of quasi-stellar object (QSO) activity in the context of galaxy evolution, several studies have questioned their importance or even their presence in QSO host galaxies. Accordingly, we are conducting a study of z {approx} 0.2 QSO host galaxies previously classified as passively evolving elliptical galaxies. We present deep Keck/LRIS spectroscopy of a sample of 15 hosts and model their stellar absorption spectra using stellar synthesis models. The high signal-to-noise ratio of our spectra allows us to break various degeneracies that arise from different combinations of models, varying metallicities, and contamination from QSO light. We find that none of the host spectra can be modeled by purely old stellar populations and that the majority of the hosts (14/15) have a substantial contribution from intermediate-age populations with ages ranging from 0.7 to 2.4 Gyr. An average host spectrum is strikingly well fit by a combination of an old population and a 2.1 (+0.5, -0.7) Gyr population. The morphologies of the host galaxies suggest that these aging starbursts were induced during the early stages of the mergers that resulted in the elliptical-shaped galaxies that we observe. The current active galactic nucleus activity likely corresponds to the late episodes of accretion predicted by numerical simulations, which occur near the end of the mergers, whereas earlier episodes may be more difficult to observe due to obscuration. Our off-axis observations prevent us from detecting any current star formation or young stellar populations that may be present in the central few kiloparsecs.

  18. Effect of long-term thermal aging on the fracture toughness of austenitic stainless steel base and weld metals

    SciTech Connect (OSTI)

    Huang, F.F.

    1995-09-27

    Compact tension specimens taken from FFTF primary piping materials (Type 316 stainless steel (SS) and 16-8-2 SS weld metal) and from reactor vessel materials (304 SS and 308 SS weld metal) were heated in laboratory furnaces from 100,000 hours. Fracture toughness testing was performed on these specimens, which are 7.62- and 25.4-mm thick, respectively at the aging temperature (482 and 427 degrees). Results were analyzed with the multiple-specimen method. Thermal aging continues to reduce the fracture toughness of FFTF component materials. Results show that thermal aging has a strong effect on the toughness degradation of weld metals, particularly for 16-8-2 SS weld whose aged/unaged Jc ratio is only 0.31 after 100,000-hour aging. The fracture toughness of the 308 and 16-8-2 SS weld metals fluctuated during 20,000 to 50,000-hour aging but deteriorated as the aging time increased to 100,000 hours; the toughness degradation is significant. Fracture control based on a fracture mechanics approach should be considered

  19. Age and isotopic relationships among the angrites Lewis Cliff 86010 and Angra dos Reis

    SciTech Connect (OSTI)

    Lugmair, G.W. ); Galer, S.J.G. Max-Planck-Inst. fuer Chemie, Mainz )

    1992-04-01

    Results of a wide-ranging isotopic investigation of the unique Antarctican angrite LEW-86010 (LEW) are presented, together with a reassessment of the type angrite Angra dos Reis (ADOR). The principal objectives of this study are to obtain precise radiometric ages, initial Sr isotopic compositions, and to search for the erstwhile presence of the short-lived nuclei {sup 146}Sm and {sup 26}Al via their daughter products. The isotopic compositions of Sm, U, Ca, and Ti were also measured. This allows a detailed appraisal to be made of the relations between, and the genealogy of, these two angrites.

  20. AmeriFlux US-Me5 Metolius-first young aged pine

    SciTech Connect (OSTI)

    Law, Bev

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Me5 Metolius-first young aged pine. Site Description - Previously old-growth ponderosa pine, clearcut in 1978 and allowed to regenerate naturally. Law et al (2001) Global Change Biology 7, 755-777; Law et al (2001) Agricultural and Forest Meteorology 110, 27-43; Anthoni et al (2002) Agricultural and Forest Meteorology 111, 203-222; Irvine & Law (2002) Global Change biology 8,1183-1194, Irivne et al (2004) Tree Physiology 24,753-763.

  1. AN AGE-OLD PHENOMENON; A COMPLEX CHALLENGE Sandia's Combustion Research Facility

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    FALL* 2000 AN AGE-OLD PHENOMENON; A COMPLEX CHALLENGE Sandia's Combustion Research Facility A QUARTERLY RESEARCH & DEVELOPMENT JOURNAL VOLUME 2, NO. 3 ALSO: Sandia Red Team Hacks All Computer Defenses New Power Company Software Helps Keep Nation's Power On S A N D I A T E C H N O L O G Y ON THE COVER: For the cover: The combustion chemistry of a blue methane flame is studied using a molecular-beam mass spectrometer. The toothlike quartz probe provides input to the spectrometer. (Photo by

  2. US/UK second level panel discussions on the health and value of: Ageing and lifetime predictions (u)

    SciTech Connect (OSTI)

    Castro, Richard G

    2011-01-18

    Many healthy physics, engineering, and materials exchanges are being accomplished in ageing and lifetime prediction that directly supports US and UK Stockpile Management Programs. Lifetime assessment studies of silicon foams under compression - Joint AWE/LANLlLLNL study of compression set in stress cushions completed. Provides phenomenological prediction out to 50 years. Polymer volatile out-gassing studies - New exchange on the out-gassing of Ethylene Vinyl Acetate (EVA) using isotopic {sup 13}C labeling studies to interrogate mechanistic processes. Infra-red (IR) gas cell analytical capabilities developed by AWE will be used to monitor polymer out-gassing profiles. Pu Strength ageing Experiments and Constitutive Modeling - In recently compared modeling strategies for ageing effects on Pu yield strength at high strain rates, a US/UK consensus was reached on the general principle that the ageing effect is additive and not multiplicative. The fundamental mechanisms for age-strengthening in Pu remains unknown. Pu Surface and Interface Reactions - (1) US/UK secondment resulted in developing a metal-metal oxide model for radiation damaged studies consistent with a Modified Embedded Atom Method (MEAM) potential; and (2) Joint US/UK collaboration to study the role of impurities in hydride initiation. Detonator Ageing (wide range of activities) - (1) Long-term ageing study with field trials at Pantex incorporating materials from LANL, LLNL, SNL and AWE; (2) Characterization of PETN growth to detonation process; (3) Detonator performance modeling; and (4) Performance fault tree analysis. Benefits are a unified approach to lifetime prediction that Includes: materials characterization and the development of ageing models through improved understanding of the relationship between materials properties, ageing properties and detonator performance.

  3. Assessment of Cable Aging Equipment, Status of Acquired Materials, and Experimental Matrix at the Pacific Northwest National Laboratory

    SciTech Connect (OSTI)

    Fifield, Leonard S.; Westman, Matthew P.; Zwoster, Andy; Schwenzer, Birgit

    2015-03-30

    The need for increased understanding of the aging and degradation behavior for polymer components of nuclear power plant electrical cables is described in this report. The highest priority materials for study and the resources available at PNNL for these studies are also described. The anticipated outcomes of the PNNL work described are : improved understanding of appropriate accelerated aging conditions, improved knowledge of correlation between observable aging indicators and cable condition in support of advanced non-destructive evaluation methods, and practical knowledge of condition-based cable lifetime prediction.

  4. Fracture toughness of plasma-sprayed thermal barrier ceramics: Influence of processing, microstructure, and thermal aging

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Dwivedi, Gopal; Viswanathan, Vaishak; Sampath, Sanjay; Shyam, Amit; Lara-Curzio, Edgar

    2014-06-09

    Fracture toughness has become one of the dominant design parameters that dictates the selection of materials and their microstructure to obtain durable thermal barrier coatings (TBCs). Much progress has been made in characterizing the fracture toughness of relevant TBC compositions in bulk form, and it has become apparent that this property is significantly affected by process-induced microstructural defects. In this investigation, a systematic study of the influence of coating microstructure on the fracture toughness of atmospheric plasma sprayed (APS) TBCs has been carried out. Yttria partially stabilized zirconia (YSZ) coatings were fabricated under different spray process conditions inducing different levelsmore » of porosity and interfacial defects. Fracture toughness was measured on free standing coatings in as-processed and thermally aged conditions using the double torsion technique. Results indicate significant variance in fracture toughness among coatings with different microstructures including changes induced by thermal aging. Comparative studies were also conducted on an alternative TBC composition, Gd2Zr2O7 (GDZ), which as anticipated shows significantly lower fracture toughness compared to YSZ. Furthermore, the results from these studies not only point towards a need for process and microstructure optimization for enhanced TBC performance but also a framework for establishing performance metrics for promising new TBC compositions.« less

  5. A laboratory exposure system to study the effects of aging on super-micron aerosol particles

    SciTech Connect (OSTI)

    Santarpia, Joshua; Sanchez, Andres L.; Lucero, Gabriel Anthony; Servantes, Brandon Lee; Hubbard, Joshua Allen

    2014-02-01

    A laboratory system was constructed that allows the super-micron particles to be aged for long periods of time under conditions that can simulate a range of natural environments and conditions, including relative humidity, oxidizing chemicals, organics and simulated solar radiation. Two proof-of-concept experiments using a non-biological simulant for biological particles and a biological simulant demonstrate the utility of these types of aging experiments. Green Visolite®, which is often used as a tracer material for model validation experiments, does not degrade with exposure to simulated solar radiation, the actual biological material does. This would indicate that Visolite® should be a good tracer compound for mapping the extent of a biological release using fluorescence as an indicator, but that it should not be used to simulate the decay of a biological particle when exposed to sunlight. The decay in the fluorescence measured for B. thurengiensis is similar to what has been previously observed in outdoor environments.

  6. NMR (Nuclear Magnetic Resonance) studies of aging effects in palladium tritide

    SciTech Connect (OSTI)

    Abell, G.C.; Attalla, A.

    1988-01-01

    This paper presents Nuclear Magnetic Resonance (NMR) studies of aging phenomena in palladium tritide. /sup 3/He NMR relaxation parameters have been measured as a function of temperature for 6-, 13-, and 22-month-old beta phase palladium tritide. The most significant result of this study is the observation of a solid/fluid phase transition near 250/degree/K of /sup 3/He that has accumulated in the PdT/sub x/ substrate via triton decay. Although the existence of solid helium at relatively high temperatures had been predicted for helium in metals, it had not previously been confirmed in any metal/helium system. The observed melting temperatures, together with the known equation of state for /sup 4/He, allow a determination of the helium density as a function of age. The atomic density obtained in this way is approximately 2.0 times that of palladium metal, agreeing with densities inferred from dilatometric measurements of other metal tritides and also with predictions based on the concept of dislocation loop punching by highly overpressurized He bubbles. The /sup 3/He signal in the 22-month-old sample was sufficiently strong to allow a detailed study of melting as a function of temperature, and provides information on the distribution of densities over the ensemble of bubbles.

  7. Thermal degradation of new and aged urethane foam and epon 826 epoxy.

    SciTech Connect (OSTI)

    Kruizenga, Alan Michael; Mills, Bernice E.

    2013-08-01

    Thermal desorption spectroscopy was used to monitor the decomposition as a function of temperature for the foam and epoxy as a function of temperature in the range of 60C to 170C. Samples were studied with one day holds at each of the studied temperatures. Both new (FoamN and EpoxyN) and aged (FoamP and EpoxyP) samples were studied. During these ~10 day experiments, the foam samples lost 11 to 13% of their weight and the EpoxyN lost 10% of its weight. The amount of weight lost was difficult to quantify for EpoxyP because of its inert filler. The onset of the appearance of organic degradation products from FoamP began at 110C. Similar products did not appear until 120C for FoamN, suggesting some effect of the previous decades of storage for FoamP. In the case of the epoxies, the corresponding temperatures were 120C for EpoxyP and 110C for EpoxyN. Suggestions for why the aged epoxy seems more stable than newer sample include the possibility of incomplete curing or differences in composition. Recommendation to limit use temperature to 90-100C for both epoxy and foam.

  8. Radiolysis and Ageing of C2-BTP in Cinnamaldehyde/Hexanol Mixtures

    SciTech Connect (OSTI)

    Fermvik, Anna; Ekberg, Christian; Retegan, Teodora; Skarnemark, Gunnar

    2007-07-01

    The separation of actinides from lanthanides is an important step in the alternative methods for nuclear waste treatment currently under development. Polycyclic molecules containing nitrogen are synthesised and used for solvent extraction. A potential problem in the separation process is the degradation of the molecule due to irradiation or ageing. An addition of nitrobenzene has proved to have an inhibitory effect on degradation when added to a system containing C2-BTP in hexanol before irradiation. In this study, 2,6-di(5,6-diethyl-1,2,4-triazine-3-yl)pyridine (C2-BTP) was dissolved in different mixtures of cinnamaldehyde and hexanol and the effects on extraction after ageing and irradiation were investigated. Similar to nitrobenzene, cinnamaldehyde contains an aromatic ring which generally has a relatively high resistance towards radiolysis. Both C2-BTP in cinnamaldehyde and C2-BTP in hexanol seem to degrade with time. The system with C2-BTP in pure hexanol is relatively stable up to 17 days but then starts slowly to degrade. The solution with pure cinnamaldehyde as diluent started to degrade after only {approx}20 hours. The opposite is true for degradation caused by radiolysis; hexanol systems are more sensitive to radiolysis than cinnamaldehyde systems. Most of the radiolytic degradation took place during the first days of irradiation, up to a dose of 4 kGy. (authors)

  9. RECONCILING THE GALACTIC BULGE TURNOFF AGE DISCREPANCY WITH ENHANCED HELIUM ENRICHMENT

    SciTech Connect (OSTI)

    Nataf, David M.; Gould, Andrew P.

    2012-06-01

    We show that the factor {approx}2 discrepancy between spectroscopic and photometric age determinations of the Galactic bulge main-sequence turnoff can be naturally explained by positing an elevated helium enrichment for the bulge relative to that assumed by standard isochrones. Helium enhancement relative to standard isochrones is confirmed at the 2.3{sigma} level. We obtain an upper bound on the helium enrichment for the metal-rich ([Fe/H] Almost-Equal-To +0.30) stars of {Delta}Y Almost-Equal-To +0.11 relative to canonical expectations, given the requirement that the spectroscopic and photometric ages be consistent and the limiting condition of instantaneous star formation. We discuss phenomenological evidence that the bulge may have had a chemical evolution that is distinct from the solar neighborhood in this manner, and we make several testable predictions. Should this emerging picture of the bulge as helium-enhanced hold, it will require the development of new isochrones, new model atmospheres, and modified analysis and cosmological interpretation of the integrated light of other bulges and elliptical galaxies.

  10. Accelerated aging of solid lubricants for the W76-1 TSL : effects of polymer outgassing.

    SciTech Connect (OSTI)

    Dugger, Michael Thomas; Wallace, William O.; Huffman, Elizabeth M.

    2006-09-01

    The behavior of MoS{sub 2} lubricants intended for the W76-1 TSL was evaluated after 17 and 82 thermal cycles, each lasting seven days and including a low temperature of -35 C and a high temperature of 93 C, in a sealed container containing organic materials. The MoS{sub 2} was applied by tumbling with MoS{sub 2} powder and steel pins (harperized), or by spraying with a resin binder (AS Mix). Surface composition measurements indicated an uptake of carbon and silicon on the lubricant surfaces after aging. Oxidation of the MoS{sub 2} on harperized coupons, where enough MoS{sub 2} was present at the surface to result in significant Mo and S concentrations, was found to be minimal for the thermal cycles in an atmosphere of primarily nitrogen. Bare steel surfaces showed a reduction in friction for exposed coupons compared to control coupons stored in nitrogen, at least for the initial cycles of sliding until the adsorbed contaminants were worn away. Lubricated surfaces showed no more than a ten percent increase in steady-state friction coefficient after exposure. Initial coefficient of friction was up to 250 percent higher than steady-state for AS Mix films on H950 coupons after 82 thermal cycles. However, the friction coefficient exhibited by lubricated coupons was never greater than 0.25, and more often less than 0.15, even after the accelerated aging exposures.

  11. Fracture toughness of plasma-sprayed thermal barrier ceramics: Influence of processing, microstructure, and thermal aging

    SciTech Connect (OSTI)

    Dwivedi, Gopal; Viswanathan, Vaishak; Sampath, Sanjay; Shyam, Amit; Lara-Curzio, Edgar

    2014-06-09

    Fracture toughness has become one of the dominant design parameters that dictates the selection of materials and their microstructure to obtain durable thermal barrier coatings (TBCs). Much progress has been made in characterizing the fracture toughness of relevant TBC compositions in bulk form, and it has become apparent that this property is significantly affected by process-induced microstructural defects. In this investigation, a systematic study of the influence of coating microstructure on the fracture toughness of atmospheric plasma sprayed (APS) TBCs has been carried out. Yttria partially stabilized zirconia (YSZ) coatings were fabricated under different spray process conditions inducing different levels of porosity and interfacial defects. Fracture toughness was measured on free standing coatings in as-processed and thermally aged conditions using the double torsion technique. Results indicate significant variance in fracture toughness among coatings with different microstructures including changes induced by thermal aging. Comparative studies were also conducted on an alternative TBC composition, Gd2Zr2O7 (GDZ), which as anticipated shows significantly lower fracture toughness compared to YSZ. Furthermore, the results from these studies not only point towards a need for process and microstructure optimization for enhanced TBC performance but also a framework for establishing performance metrics for promising new TBC compositions.

  12. Characterization of poly(vinyl chloride) aged in a bromine containing electrolyte

    SciTech Connect (OSTI)

    Arnold, C. Jr.; Leo, A.; Tarjani, M.

    1988-01-01

    Poly(vinyl chloride) (PVC) is being considered for use as a flow frame material in a developmental zinc/bromine battery. The choice of PVC was based on its low cost and the ease with which it can be molded into complex parts. The electrolyte used in this battery is a highly corrosive mixture of bromine, zinc bromide, zinc chloride, potassium bromide, potassium chloride and a quaternary amine salt. The quaternary salt serves to reduce the concentration of free bromine in the electrolyte by virtue of its complexing capability. It is well known that aqueous bromine is capable of oxidizing organic compounds. The purpose of the current study was to investigate the effect of a bromine electrolyte on two PVC formulations, PVC-1 and PVC-4. PVC-1 is the designation given to one of B.F. Goodrich's commercial formulations and is the present baseline material for the flow frame. PVC-4 is an experimental B.F. Goodrich formulation that was developed especially for battery applications. We sought answers to such questions as (1) does oxidation and/or bromination take place. (2) does bromine penetrate into the sample and, if so, how far. (3) how are the mechanical and morphological properties affected. and (4) are there differences in stability between PVC-1 and PVC-4. To accelerate the aging processes we aged the PVC samples at an elevated temperature in an electrolyte which did not contain any complexing agent. 5 refs., 6 figs.

  13. Cable Polymer Aging and Condition Monitoring Research at Sandia National Laboratores Under the Nuclear Energy Plant Optimization (NEPO) Program

    SciTech Connect (OSTI)

    K. Gillen; R. Assink; R. Bernstein

    2005-12-23

    This report describes cable polymer aging and condition monitoring research performed at Sandia National Laboratories under the Nuclear Energy Plant Optimization (NEPO) Program from 2000 to 2005. The research results apply to low-voltage cable insulation and Program from 2000 to 2005. The research results apply to low-voltage cable insulation and jacket materials that are commonly used in U.S. nuclear power plants. The research builds upon and is liked to research performed at Sandia from 1977 through 1986, sponsored by the U.S. Nuclear Regulatory Commission. Aged and unaged specimens from that research remained available and were subjected to further testing under the NEPO research effort.The documented results from the earlier research were complemented by subjecting the specimens to new condition monitoring tests. Additional aging regimens were applied to additional specimens to develop aging models for key cable jacket and insulation materials

  14. Review of nuclear power plant safety cable aging studies with recommendations for improved approaches and for future work.

    SciTech Connect (OSTI)

    Gillen, Kenneth Todd; Bernstein, Robert

    2010-11-01

    Many U. S. nuclear power plants are approaching 40 years of age and there is a desire to extend their life for up to 100 total years. Safety-related cables were originally qualified for nuclear power plant applications based on IEEE Standards that were published in 1974. The qualifications involved procedures to simulate 40 years of life under ambient power plant aging conditions followed by simulated loss of coolant accident (LOCA). Over the past 35 years or so, substantial efforts were devoted to determining whether the aging assumptions allowed by the original IEEE Standards could be improved upon. These studies led to better accelerated aging methods so that more confident 40-year lifetime predictions became available. Since there is now a desire to potentially extend the life of nuclear power plants way beyond the original 40 year life, there is an interest in reviewing and critiquing the current state-of-the-art in simulating cable aging. These are two of the goals of this report where the discussion is concentrated on the progress made over the past 15 years or so and highlights the most thorough and careful published studies. An additional goal of the report is to suggest work that might prove helpful in answering some of the questions and dealing with some of the issues that still remain with respect to simulating the aging and predicting the lifetimes of safety-related cable materials.

  15. Aging Behavior of the Viton® Fluoroelastomer O-Rings in the 9975 Shipping Package

    SciTech Connect (OSTI)

    Daugherty, W.; Mcwilliams, A.; Skidmore, E.

    2015-06-09

    The 9975 Type B shipping package is used within the DOE complex for shipping special nuclear materials. This package is re-certified annually in accordance with Safety Analysis Report requirements. The package is also used at the Savannah River Site as part of the long-term storage configuration of special nuclear materials. As such, the packages do not undergo annual recertification during storage, with uncertainty as to how long some of the package components will meet their functional requirements in the storage environment. The packages are currently approved for up to 15 years storage, and work continues to provide a technical basis to extend that period. This paper describes efforts by the Savannah River National Laboratory (SRNL) to extend the service life estimate of Viton® GLT and GLT-S fluoroelastomer O-rings used in the 9975 shipping package. O-rings of both compositions are undergoing accelerated aging at elevated temperature, and are periodically tested for compression stress relaxation (CSR) behavior and leak performance. The CSR behavior of O-rings was evaluated at temperatures from 79 °C to 177 °C. These collective data were used to develop predictive models for extrapolation of CSR behavior to relevant service temperatures (< 75 °C). O-rings were also aged in Primary Containment Vessel (PCV) fixtures at temperatures ranging from 79 °C to 232 °C. The fixtures are helium leak tested periodically to determine if they remain leak-tight. The PCV fixture tests demonstrate that the 9975 O-rings will remain leak-tight at temperatures up to 149 °C for 3 years or more, and no leak failures have been observed with up to 8 years aging at 93 °C. Significantly longer periods of leak-tight service are expected at the lower temperatures actually experienced in the storage environment. The predictive model developed from the CSR data conservatively indicates a service life of more than 20 years at the bounding temperature of 75 °C. Although the relationship between CSR behavior and leak-tight performance has not been established for this design, the CSR predictions for this O-ring are conservative relative to leak-tight performance to date.

  16. U-Pb Ages of Secondary Silica at Yucca Mountain, Nevada: Implications for the Paleohydrology of the Unsaturated Zone

    SciTech Connect (OSTI)

    L.A. Neymark; Y. Amelin; J.B. Paces; Z.E. Peterman

    2001-08-20

    U, Th, and Pb isotopes were analyzed in layers of opal and chalcedony from individual millimeter- to centimeter-thick calcite and silica coatings at Yucca Mountain, Nevada, USA, a site that is being evaluated for a potential high-level nuclear waste repository. These calcite and silica coatings on fractures and in lithophysal cavities in Miocene-age tuffs in the unsaturated zone (UZ) precipitated from descending water and record a long history of percolation through the UZ. Opal and chalcedony have high concentrations of U (10 to 780 ppm) and low concentrations of common Pb as indicated by large values of {sup 206}Pb/{sup 204}Pb (up to 53,806), thus making them suitable for U-Pb age determinations. Interpretations of U-Pb isotopes in opal samples at Yucca Mountain are complicated by the incorporation of excess {sup 234}U at the time of mineral formation, resulting in reverse discordance of U-Pb ages. However, the {sup 207}Pb/{sup 235}U ages are much less affected by deviation from initial secular equilibrium and provide reliable ages of most silica deposits between 0.6 and 9.8 Ma. For chalcedony subsamples showing normal age discordance, these ages may represent minimum times of deposition. Typically, {sup 207}Pb/{sup 235}U ages are consistent with the microstratigraphy in the mineral coating samples, such that the youngest ages are for subsamples from outer layers, intermediate ages are from inner layers, and oldest ages are from innermost layers. {sup 234}U and {sup 230}Th in most silica layers deeper in the coatings are in secular equilibrium with {sup 238}U, which is consistent with their old age and closed system behavior during the past 0.5 m.y. U-Pb ages for subsamples of silica layers from different microstratigraphic positions in individual calcite and silica coating samples collected from lithophysal cavities in the welded part of the Topopah Spring Tuff yield slow long-term average depositional rates of 1 to 5 mm/m.y. These data imply that the deeper parts of the UZ at Yucca Mountain maintained long-term hydrologic stability over the past 10 m.y. despite significant climate variations. U-Pb ages for subsamples of silica layers from different microstratigraphic positions in individual calcite and silica coating samples collected from fractures in the welded part of the overlying Tiva Canyon Tuff indicate larger long-term average depositional rates up to 23 mm/m.y. and an absence of recently deposited materials (ages of outermost layers are 3-5 Ma). These differences between the characteristics of the coatings for samples from the shallower and deeper parts of the UZ may indicate that the nonwelded tuffs (PTn), located between the welded parts of the Tiva Canyon and Topopah Spring Tuffs, play an important role in moderating UZ flow.

  17. Synthesis and characterization of WO{sub 3} nanostructures prepared by an aged-hydrothermal method

    SciTech Connect (OSTI)

    Huirache-Acuna, R.; Paraguay-Delgado, F.; Albiter, M.A.; Lara-Romero, J.; Martinez-Sanchez, R.

    2009-09-15

    Nanostructures of tungsten trioxide (WO{sub 3}) have been successfully synthesized by using an aged route at low temperature (60 deg. C) followed by a hydrothermal method at 200 deg. C for 48 h under well controlled conditions. The material was studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Energy Dispersive Spectroscopy (EDS), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). Specific Surface Area (S{sub BET}) were measured by using the BET method. The lengths of the WO{sub 3} nanostructures obtained are between 30 and 200 nm and their diameters are from 20 to 70 nm. The growth direction of the tungsten oxide nanostructures was determined along [010] axis with an inter-planar distance of 0.38 nm.

  18. EXAMINATION OF 80 DEGREES C DESORPTION ISOTHERMS OFTRITIUM AGED PD/K AND LANA.75

    SciTech Connect (OSTI)

    Staack, G; Kirk Shanahan, K; Tom Walters, T; Roger Pilgrim, R

    2007-08-28

    Metal hydrides, specifically Pd deposited on kieselguhr (Pd/k) and LaNi{sub 4.25}Al{sub 0.75} (LANA.75), have been used at the Savannah River Site for almost twenty years for hydrogen isotope separation and storage. Radiolytic decay of tritium to helium-3 in the metal matrix causes three classic changes in the performance of the hydride: the plateau pressure decreases, the plateau slope increases, and a heel forms, reducing the reversible capacity of the hydride. Deuterium and tritium isotherms were collected on the virgin materials, only tritium isotherms were collected at approximately 2 years, and both deuterium and tritium isotherms were collected at approximately 3.5 years of quiescent aging. Points of interest include those mentioned above as well as the effects of cycling the materials. The methods and results are presented.

  19. The age of the martian meteorite Northwest Africa 1195 and the differentiation history of the shergottites

    SciTech Connect (OSTI)

    Symes, S; Borg, L; Shearer, C; Irving, A

    2007-04-05

    Samarium-neodymium isotopic analyses of unleached and acid-leached mineral fractions from the recently identified olivine-bearing shergottite Northwest Africa 1195 yield a crystallization age of 348 {+-} 19 Ma and an {var_epsilon}{sub Nd}{sup 143} value of +40.1 {+-} 1.3. Maskelynite fractions do not lie on the Sm-Nd isochron and appear to contain a martian surface component with low {sup 147}Sm/{sup 144}Nd and {sup 143}Nd/{sup 144}Nd ratios that was added during shock. The Rb-Sr system is disturbed and does not yield an isochron. Terrestrial Sr appears to have affected all of the mineral fractions, although a maximum initial {sup 87}Sr/{sup 86}Sr ratio of 0.701614 {+-} 16 is estimated by passing a 348 Ma reference isochron through the maskelynite fraction that is least affected by contamination. The high initial {var_epsilon}{sub Nd}{sup 143} value and the low initial {sup 87}Sr/{sup 86}Sr ratio, combined with the geologically young crystallization age, indicate that Northwest Africa 1195 is derived from a source region characterized by a long-term incompatible element depletion. The age and initial Sr and Nd isotopic compositions of Northwest Africa 1195 are very similar to those of Queen Alexandra Range 94201, indicating these samples were derived from source regions with nearly identical Sr-Nd isotopic systematics. These similarities suggest that these two meteorites share a close petrogenetic relationship and might have been erupted from a common volcano. The meteorites Yamato 980459, Dar al Gani 476, Sayh al Uhaymir 005/008, and Dhofar 019 also have relatively old ages between 474-575 Ma and trace element and/or isotopic systematics that are indicative of derivation from incompatible-element-depleted sources. This suggests that the oldest group of meteorites is more closely related to one another than they are to the younger meteorites that are derived from less incompatible-element-depleted sources. Closed-system fractional crystallization of this suite of meteorites is modeled with the MELTS algorithm using the bulk composition of Yamato 980459 as a parent. These models reproduce many of the major element and mineralogical variations observed in the suite. In addition, the rare-earth element systematics of these meteorites are reproduced by fractional crystallization using the proportions of phases and extents of crystallization that are calculated by MELTS. The combined effects of source composition and fractional crystallization are therefore likely to account for the major element, trace element, and isotopic diversity of all shergottites. Thus, assimilation of a martian crustal component is not required to explain the geochemical diversity of the shergottites.

  20. A collaborative success story -- The rebirth of an aging waste-to-energy plant

    SciTech Connect (OSTI)

    Shultz, D.S.

    1996-12-31

    In 1993 American Ref-Fuel purchased an early generation waste-to-energy plant burdened with technical and environmental obsolescence and facing eminent closure. Through the successful collaboration of public regulatory agencies, private industry, local government and organized labor, the facility will be retrofitted and repowered to meet new source performance emission standards and re-established as an integral component in the Niagara Frontier`s solid waste disposal scheme. The environmental revitalization of this Niagara Falls, New York plant will require a capital expenditure of $150 million and construction work is scheduled to be completed by mid 1996. This case study is an example of how aging environmental infrastructure, through careful planning and collaboration between the public and private sector, can be retrofitted for the next century while maintaining employing and contributing over $193 million to the local economy.

  1. Fundamental and applied studies of helium ingrowth and aging in plutonium

    SciTech Connect (OSTI)

    Stevens, M.F.; Zocco, T.; Albers, R.; Becker, J.D.; Walter, K.; Cort, B.; Paisley, D.; Nastasi, M.

    1998-12-31

    This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The purpose of this project was to develop new capabilities to assess the nucleation and growth of helium-associated defects in aged plutonium metal. This effort involved both fundamental and applied models to assist in predicting the transport and kinetics of helium in the metal lattice as well as ab initio calculations of the disposition of gallium in the fcc plutonium lattice and its resulting effects on phase stability. Experimentally this project aimed to establish experimental capabilities crucial to the prediction of helium effects in metals, such as transmission electron microscopy, thermal helium effusion, and the development of a laser-driven mini-flyer for understanding the role of helium and associated defects on shock response of plutonium surrogates.

  2. Campaign 1.7 Pu Aging. Development of Time of Flight Secondary Ion Mass Spectroscopy

    SciTech Connect (OSTI)

    Venhaus, Thomas J.

    2015-09-09

    The first application of Time-of-Flight Secondary Ion Mass Spectroscopy (ToF-SIMS) to an aged plutonium surface has resulted in a rich set of surface chemistry data, as well as some unexpected results. FY15 was highlighted by not only the first mapping of hydrogen-containing features within the metal, but also a prove-in series of experiments using the systems Sieverts Reaction Cell. These experiments involved successfully heating the sample to ~450 oC for nearly 24 hours while the sample was dosed several times with hydrogen, followed by an in situ ToF-SIMS analysis. During this year, the data allowed for better and more consistent identification of the myriad peaks that result from the SIMS sputter process. In collaboration with the AWE (U.K), the system was also fully aligned for sputter depth profiling for future experiments.

  3. The sup 36 Cl ages of the brines in the Magadi-Natron basin, east Africa

    SciTech Connect (OSTI)

    Kaufman, A.; Margaritz, M.A.; Hollos, G. ); Paul, M.; Boaretto, E. ); Hillaire-Marcel, C. ); Taieb, M. )

    1990-10-01

    The depression in the East African Rift which includes both Lake Magadi and Lake Natron forms a closed basin within which almost all the dissolved chloride originates in precipitation, since there is no important source of very ancient sedimentary chloride. This provides an ideal setting for the evaluation of the {sup 36}Cl methodology as a geochemical and hydrological tracer. The main source of recent water, as represented by the most dilute samples measured, is characterized by a {sup 36}Cl/Cl ratio of 2.5 {times} 10{sup {minus}14}, in agreement with the calculated value expected in precipitation. Surface evaporation increases the chlorinity of the local freshwater inflow by about a factor of 110 without changing the isotopic ratio, indicating that little chloride enters the system in the form of sediment leachate. A second type of brine found in the basin occurs in a hot deep groundwater reservoir and is characterized by lower {sup 36}Cl/Cl ratios (<1.2 {times} 10{sup {minus}14}). By comparing this value with the 2.5 {times} 10{sup {minus}14} in recent recharge, one obtains an approximate salt accumulation age of 760 Ka which is consistent with thee time of the first appearance of the lake. These older brines also have lower {sup 18}O and {sup 2}H values which indicate that they were recharged during a climatically different era. The {sup 36}Cl/Cl ratios in the inflowing waters and in the accumulated brine, together with the known age of the Lake Magadi basin, may be used to estimate the importance of the hypogene and epigene, as opposed to the meteoric, mode of {sup 36}Cl production. Such a calculation shows that the hypogene and epigene processes together contribute less than 6% of the total {sup 36}Cl present in the lake.

  4. Differential regulation of apoptosis in slow and fast twitch muscles of aged female F344BN rats

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Rice, Kevin M.; Manne, Nandini D. P. K.; Gadde, Murali K.; Paturi, Satyanarayana; Arvapalli, Ravikumar; Blough, Eric

    2015-03-28

    Age-related muscle atrophy is characterized by decreases in muscle mass and is thought be mediated, at least in part, by increases in myocyte apoptosis. Recent data has demonstrated that the degree of muscle loss with aging may differ between males and females while other work has suggested that apoptosis as indicated by DNA fragmentation may be regulated differently in fast- and slow-twitch muscles. Herein, we investigate how aging affects the regulation of muscle apoptosis in the fast-twitch extensor digitorum longus (EDL) and slow-twitch soleus muscles of young (6-month), aged (26-month), and very aged (30-month) female Fischer 344/NNiaHSD × Brown Norway/BiNiamore » (F344BN) rats. Tissue sections were stained with hydroethidium for ROS and protein extract was subjected to immunoblotting for assessing apoptotic markers. Our data suggest that decreases in muscle mass were associated with increased DNA fragmentation (TUNEL positive) and increases in reactive oxygen species (ROS) as determined by hydroethidium staining in both the EDL and soleus. Similar to our previous work using aged male animals, we observed that the time course and magnitude of changes in Bax, Bcl-2, caspase-3, caspase-9, and cleavage of α-fodrin protein were regulated differently between muscles. As a result, These data suggest that aging in the female F344BN rat is associated with decreases in muscle mass, elevations in ROS level, increased muscle cell DNA fragmentation, and alterations in cell membrane integrity and that apoptotic mechanisms may differ between fiber types.« less

  5. Accelerated Aging of BKC 44306-10 Rigid Polyurethane Foam: FT-IR Spectroscopy, Dimensional Analysis, and Micro Computed Tomography

    SciTech Connect (OSTI)

    Gilbertson, Robert D.; Patterson, Brian M.; Smith, Zachary

    2014-01-02

    An accelerated aging study of BKC 44306-10 rigid polyurethane foam was carried out. Foam samples were aged in a nitrogen atmosphere at three different temperatures: 50 C, 65 C, and 80 C. Foam samples were periodically removed from the aging canisters at 1, 3, 6, 9, 12, and 15 month intervals when FT-IR spectroscopy, dimensional analysis, and mechanical testing experiments were performed. Micro Computed Tomography imaging was also employed to study the morphology of the foams. Over the course of the aging study the foams the decreased in size by a magnitude of 0.001 inches per inch of foam. Micro CT showed the heterogeneous nature of the foam structure likely resulting from flow effects during the molding process. The effect of aging on the compression and tensile strength of the foam was minor and no cause for concern. FT-IR spectroscopy was used to follow the foam chemistry. However, it was difficult to draw definitive conclusions about the changes in chemical nature of the materials due to large variability throughout the samples.

  6. Letter report: Population estimates by age, sex and race for 10-county study area. Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Pittenger, D.B.

    1992-02-01

    The Hanford Environmental Does Reconstruction (HEDR) Project was established to estimate radiation doses that people could have received from nuclear operations at the Hanford Site since 1944. To identify groups that may have received doses, population estimates containing age, race, and sex detail for ten counties in Washington and Oregon for the years 1940 to 1980 were prepared by the Demographics Laboratory under a subcontract with the Pacific Northwest Laboratory (PNL). A data base of population information was developed from census reports and published and unpublished collections from the Washington State Office of Financial Management and Center for Population Research. Three estimation methods were then explored: the cohort-component model, cohort interpolation, and age-group interpolation. The estimates generated through cohort and age-group interpolation are considered adequate for initial use in the HEDR Project. Results are presented in two forms: (1) county populations by sex and single year of age and (2) county populations by sex and race for age groupings. These results are made available to the HEDR Project for further refinement into population estimates by county census divisions.

  7. 230Th-234U Age-Dating Uranium by Mass Spectrometry

    SciTech Connect (OSTI)

    Williams, R W; Gaffney, A M

    2012-04-18

    This is the standard operating procedure used by the Isotope Ratio Mass Spectrometry Group of the Chemical Sciences Division at LLNL for the preparation of a sample of uranium oxide or uranium metal for {sup 230}Th-{sup 234}U age-dating. The method described here includes the dissolution of a sample of uranium oxide or uranium metal, preparation of a secondary dilution, spiking of separate aliquots for uranium and thorium isotope dilution measurements, and purification of uranium and thorium aliquots for mass spectrometry. This SOP may be applied to uranium samples of unknown purity as in a nuclear forensic investigation, and also to well-characterized samples such as, for example, U{sub 3}O{sub 8} and U-metal certified reference materials. The sample of uranium is transferred to a quartz or PFA vial, concentrated nitric acid is added and the sample is heated on a hotplate at approximately 100 C for several hours until it dissolves. The sample solution is diluted with water to make the solution approximately 4 M HNO{sub 3} and hydrofluoric acid is added to make it 0.05 M HF. A secondary dilution of the primary uranium solution is prepared. Separate aliquots for uranium and thorium isotope dilution measurements are taken and spiked with {sup 233}U and {sup 229}Th, respectively. The spiked aliquot for uranium isotope dilution analysis is purified using EiChrom UTEVA resin. The spiked aliquot for thorium isotope dilution analysis is purified by, first, a 1.8 mL AG1x8 resin bed in 9 M HCl on which U adsorbs and Th passes through; second, adsorbing Th on a 1 mL AG1x8 resin bed in 8 M HNO{sub 3} and then eluting it with 9 M HCl followed by 0.1 M HCl + 0.005 M HF; and third, by passing the Th through a final 1.0 mL AG1x8 resin bed in 9 M HCl. The mass spectrometry is performed using the procedure 'Th and U Mass Spectrometry for {sup 230}Th-{sup 234}U Age Dating'.

  8. Mid-infrared followup of cold brown dwarfs: diversity in age, mass and metallicity

    SciTech Connect (OSTI)

    Saumon, Didier; Leggett, Sandy K; Burningham, Ben; Marley, Mark S; Waren, S J; Jones, H R A; Pinfield, D J; Smart, R L

    2009-01-01

    We present new Spitzer IRAC [3.6], [4.5], [5.8] and [8.0] photometry of nine very late-type T dwarfs. Combining this with previously published photometry, we investigate trends with type and color that are useful for both the planning and interpretation of infrared surveys designed to discover the coldest T or Y dwarfs. Brown dwarfs with effective temperature (T{sub eff}) below 700 K emit more than half their flux at wavelengths longer than 3 {micro}m, and the ratio of the mid-infrared flux to the near-infrared flux becomes very sensitive to T{sub eff} at these low temperatures. We confirm that the color H (1.6 {micro}m) - [4.5] is a good indicator of T{sub eff} with a relatively weak dependence on metallicity and gravity. Conversely, the colors H - K (2.2 {micro}m) and [4.5] - [5.8] are sensitive to metallicity and gravity. Thus near- and mid-infrared photometry provide useful indicators of the fundamental properties of brown dwarfs, and if temperature and gravity are known, then mass and age can be reliably determined from evolutionary models. There are twelve dwarfs currently known with H - [4.5] > 3.0, and {approx} 500 < T{sub eff} K {approx}< 800, which we examine in detail. The ages of the dwarfs in the sample range from very young (0.1 - 1.0 Gyr) to relatively old (3 - 12 Gyr). The mass range is possibly as low as 5 Jupiter masses to up to 70 Jupiter masses, i.e. near the hydrogen burning limit. The metallicities also span a large range, from [m/H]= -0.3 to [m/H]= +0.2. The small number of T8 - T9 dwarfs found in the UKIRT Infrared Deep Sky Survey to date appear to be predominantly young low-mass dwarfs. Accurate mid-infrared photometry of cold brown dwarfs is essentially impossible from the ground, and extensions to the mid-infrared space missions warm-Spitzer and WISE are desirable in order to obtain the vital mid-infrared data for cold brown dwarfs, and to discover more of these rare objects.

  9. TCP Final Report: Measuring the Effects of Stand Age and Soil Drainage on Boreal Forest

    SciTech Connect (OSTI)

    Michael L. Goulden

    2007-05-02

    This was a 6-year research project in the Canadian boreal forest that focused on using field observations to understand how boreal forest carbon balance changes during recovery from catastrophic forest fire. The project began with two overarching goals: (1) to develop techniques that would all the year round operation of 7 eddy covariance sites in a harsh environment at a much lower cost than had previously been possible, and (2) to use these measurements to determine how carbon balance changes during secondary succession. The project ended in 2006, having accomplished its primary objectives. Key contributions to DOE during the study were: (1) Design, test, and demonstrate a lightweight, fully portable eddy flux system that exploits several economies of scale to allow AmeriFlux-quality measurements of CO{sub 2} exchange at many sites for a large reduction in cost (Goulden et al. 2006). (2) Added seven year-round sites to AmeriFlux, at a relatively low per site cost using the Eddy Covariance Mesonet approach (Goulden et al. 2006). These data are freely available on the AmeriFlux web site. (3) Tested and rejected the conventional wisdom that forests lose large amounts of carbon during the first decade after disturbance, then accumulate large amounts of carbon for {approx}several decades, and then return to steady state in old age. Rather, we found that boreal forests recovers quickly from fire and begins to accumulate carbon within {approx}5 years after disturbance. Additionally, we found no evidence that carbon accumulation declines in old stands (Goulden et al. 2006, Goulden et al. in prep). (4) Tested and rejected claims based on remote sensing observations (for example, Myneni et al 1996 using AVHRR) that regions of boreal forest have changed markedly in the last 20 years. Rather, we assembled a much richer data set than had been used in the past (eddy covariance observations, tree rings, biomass, NPP, AVHRR, and LandSat), which we used to establish that the forests in our study region have remained largely constant over the last 20 years after accounting for the effects of stand age and succession (McMillen et al. in review).

  10. Evaluation of the effect of organic pro-degradant concentration in polypropylene exposed to the natural ageing

    SciTech Connect (OSTI)

    Montagna, L. S. E-mail: andrecatto@terra.com.br E-mail: mmcforte@hotmail.com Catto, A. L. E-mail: andrecatto@terra.com.br E-mail: mmcforte@hotmail.com Rossini, K. E-mail: andrecatto@terra.com.br E-mail: mmcforte@hotmail.com Forte, M. M. C. E-mail: andrecatto@terra.com.br E-mail: mmcforte@hotmail.com Santana, R. M. C. E-mail: andrecatto@terra.com.br E-mail: mmcforte@hotmail.com

    2014-05-15

    The production and consumption of plastics in the last decade has recorded a remarkable increase in the scientific and industrial interest in environmentally degradable polymer (EDPs). Polymers wastes are deposited improperly, such as dumps, landfills, rivers and seas, causing a serious problem by the accumulation in the environment. The abiotic processes, like the photodegradation, are the most efficient occurring in the open environmental, where the polymers undergo degradation from the action of sunlight that result from direct exposure to solar radiation, however depend of the type of chemical ageing, which is the principal component of climatic ageing. The subject of this work is to study the influence of concentration of organic pro-degradant (1, 2 and 3 % w/w) in the polypropylene (PP) exposed in natural ageing. PP samples with and without the additive were processed in plates square form, obtained by thermal compression molding (TCM) using a press at 200C under 2 tons for 5 min, and then were exposed at natural ageing during 120 days. The presence of organic additive influenced on PP degradability, this fact was assessed by changes in the thermal and morphology properties of the samples after 120 days of natural ageing. Scanning Electronic Microscopy (SEM) results of the morphological surface of the modified PP samples showed greater degradation photochemical oxidative when compared to neat PP, due to increase of rugosity and formation of microvoids. PP samples with different pro-degradant concentration under natural ageing presented a degree of crystallinity, obtained by Differential Scanning Calorimeter (DSC) increases in comparing the neat PP.

  11. Helium bubble linkage and the transition to rapid He release in aging Pd tritide.

    SciTech Connect (OSTI)

    Cowgill, Donald F.

    2006-02-01

    A model is presented for the linking of helium bubbles growing in aging metal tritides. Stresses created by neighboring bubbles are found to produce bubble growth toward coalescence. This process is interrupted by the fracture of ligaments between bubble arrays. The condition for ligament fracture percolates through the material to reach external surfaces, leading to material micro-cracking and the release of helium within the linked-bubble cluster. A comparison of pure coalescence and pure fracture mechanisms shows the critical HeM concentration for bubble linkage is not strongly dependent on details of the linkage process. The combined stress-directed growth and fracture process produces predictions for the onset of rapid He release and the He emission rate. Transition to this rapid release state is determined from the physical size of the linked-bubble clusters, which is calculated from dimensional invariants in classical percolation theory. The result is a transition that depends on material dimensions. The onset of bubble linkage and rapid He release are found to be quite sensitive to the bubble spacing distribution, which is log-normal for bubbles nucleated by self-trapping.

  12. Effect of natural ageing on volume stability of MSW and wood waste incineration residues

    SciTech Connect (OSTI)

    Gori, Manuela; Bergfeldt, Britta; Reichelt, Jrgen; Sirini, Piero

    2013-04-15

    Highlights: ? Natural weathering on BA from MSW and wood waste incineration was evaluated. ? Type of mineral phases, pH and volume stability were considered. ? Weathering reactions effect in improved stability of the materials. - Abstract: This paper presents the results of a study on the effect of natural weathering on volume stability of bottom ash (BA) from municipal solid waste (MSW) and wood waste incineration. BA samples were taken at different steps of treatment (fresh, 4 weeks and 12 weeks aged) and then characterised for their chemical and mineralogical composition and for volume stability by means of the mineralogical test method (M HMVA-StB), which is part of the German quality control system for using aggregates in road construction (TL Gestein-StB 04). Changes of mineralogical composition with the proceeding of the weathering treatment were also monitored by leaching tests. At the end of the 12 weeks of treatment, almost all the considered samples resulted to be usable without restrictions in road construction with reference to the test parameter volume stability.

  13. Structural Aging Program technical progress for period, January 1, 1992--December 31, 1992

    SciTech Connect (OSTI)

    Naus, D.J.; Oland, C.B.

    1993-07-01

    The Structural Aging (SAG) Program is conducted for the Nuclear Regulatory Commission (NRC) by the Oak Ridge National Laboratory (ORNL). The program has the overall objective of preparing an expandable handbook or report which will provide potential structural safety issues and acceptance criteria for use by the NRC in nuclear power plant evaluations of continued service. Initial focus of the program is on concrete and concrete-related materials which comprise safety-related (Category I) structures in light-water reactor facilities. The SAG Program is organized into four tasks: Task S.1 -- Program Management, Task S.2 -- Materials Property Data Base, Task S.3 -- Structural Component Assessment/Repair Technology, and Task S.4 -- Quantitative Methodology for Continued Service Determinations. In meeting the individual objectives of these tasks resources are drawn from ORNL with subcontract support from universities and other research laboratories. This report provides an overview of principal developments in each of the four program tasks from January 1, 1992 to December 31, 1992. Planned activities under each of these tasks are also presented.

  14. Formation and aging of secondary organic aerosol from toluene: changes in chemical composition, volatility, and hygroscopicity

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hildebrandt Ruiz, L.; Paciga, A. L.; Cerully, K. M.; Nenes, A.; Donahue, N. M.; Pandis, S. N.

    2015-07-24

    Secondary organic aerosol (SOA) is transformed after its initial formation, but this chemical aging of SOA is poorly understood. Experiments were conducted in the Carnegie Mellon environmental chamber to form secondary organic aerosol (SOA) from the photo-oxidation of toluene and other small aromatic volatile organic compounds (VOCs) in the presence of NOx under different oxidizing conditions. The effects of the oxidizing condition on organic aerosol (OA) composition, mass yield, volatility, and hygroscopicity were explored. Higher exposure to the hydroxyl radical resulted in different OA composition, average carbon oxidation state (OSc), and mass yield. The OA oxidation state generally increased duringmore » photo-oxidation, and the final OA OSc ranged from -0.29 to 0.16 in the performed experiments. The volatility of OA formed in these different experiments varied by as much as a factor of 30, demonstrating that the OA formed under different oxidizing conditions can have a significantly different saturation concentration. There was no clear correlation between hygroscopicity and oxidation state for this relatively hygroscopic SOA.« less

  15. XPD Helicase Structures and Activities: Insights into the Cancer and Aging Phenotypes from XPD Mutations

    SciTech Connect (OSTI)

    Tainer, John; Fan, Li; Fuss, Jill O.; Cheng, Quen J.; Arvai, Andrew S.; Hammel, Michal; Roberts, Victoria A.; Cooper, Priscilla K.; Tainer, John A.

    2008-06-02

    Mutations in XPD helicase, required for nucleotide excision repair (NER) as part of the transcription/repair complex TFIIH, cause three distinct phenotypes: cancer-prone xeroderma pigmentosum (XP), or aging disorders Cockayne syndrome (CS), and trichothiodystrophy (TTD). To clarify molecular differences underlying these diseases, we determined crystal structures of the XPD catalytic core from Sulfolobus acidocaldarius and measured mutant enzyme activities. Substrate-binding grooves separate adjacent Rad51/RecA-like helicase domains (HD1, HD2) and an arch formed by 4FeS and Arch domains. XP mutations map along the HD1 ATP-binding edge and HD2 DNA-binding channel and impair helicase activity essential for NER. XP/CS mutations both impair helicase activity and likely affect HD2 functional movement. TTD mutants lose or retain helicase activity but map to sites in all four domains expected to cause framework defects impacting TFIIH integrity. These results provide a foundation for understanding disease consequences of mutations in XPD and related 4Fe-4S helicases including FancJ.

  16. REVIEW OF AGING DATA ON EPDM O-RINGS IN THE H1616 SHIPPING PACKAGE

    SciTech Connect (OSTI)

    Skidmore, E.

    2012-03-27

    Currently, all H1616 shipping package containers undergo annual re-verification testing, including containment vessel leak testing to verify leak-tightness (<1 x 10{sup -7} ref cc/sec air) as per ANSI N14.5. The purpose of this literature review is to supplement aging studies currently being performed by SRNL on the EPDM O-rings to provide the technical basis for extending annual re-verification testing for the H1616 shipping package and to predict the life of the seals at bounding service conditions. The available data suggest that the EPDM O-rings can retain significant mechanical properties and sealing force at or below bounding service temperatures (169 F or 76 C) beyond the 1 year maintenance period. Interpretation of available data suggests that a service life of at least 2 years and potentially 4-6 years may be possible at bounding temperatures. Seal lifetimes at lower, more realistic temperatures will likely be longer. Being a hydrocarbon elastomer, EPDM O-rings may exhibit an inhibition period due to the presence of antioxidants. Once antioxidants are consumed, mechanical properties and seal performance could decline at a faster rate. Testing is being performed to validate the assumptions outlined in this report and to assess the long-term performance of O-ring seals under actual service conditions.

  17. Aging model for solid lubricants used in weapon stronglinks: tribological performance and hardware review

    SciTech Connect (OSTI)

    Dugger, M.T.; Peebles, D.E.; Sorroche, E.H.; Varga, K.S.; Bryan, R.M.

    1997-09-01

    The solid lubricant used most extensively in strong links throughout the enduring stockpile contains MoS{sub 2}, which is known to react with oxygen and water vapor resulting in a change in the material`s friction and wear behavior. The authors have examined the frictional behavior of this lubricant as a function of oxidation, in support of efforts to quantify the impact of changes in the material on the dynamic behavior of the MC2969 strong link. Their results show that the friction response of oxidized lubricant is strongly influenced by the amount of burnishing performed on the lubricant after deposition. Low levels of burnish leave a thick film, of which only the near surface degrades during oxidation. Rapid wear of the oxidized material leaves a surface whose properties are the same as non-oxidized material. Higher levels of burnish leave a thinner film of lubricant such that the entire film may be oxidized. The friction coefficient on this surface reaches a steady state value greater than that of non oxidized material. In addition to these fundamental differences in steady state behavior, they have shown that the initial friction coefficient on oxidized surfaces is related to the amount of sulfide converted to sulfate, regardless of the oxidation conditions used. Measurements on parts returned from the stockpile show that the friction behavior of aged hardware is consistent with the behavior observed on controlled substrates containing thin lubricant films.

  18. STAR FORMATION IN ULTRA-FAINT DWARFS: CONTINUOUS OR SINGLE-AGE BURSTS?

    SciTech Connect (OSTI)

    Webster, David; Bland-Hawthorn, Joss; Sutherland, Ralph

    2015-01-30

    We model the chemical evolution of six ultra-faint dwarfs (UFDs): Bootes I, Canes Venatici II, Coma Berenices, Hercules, Leo IV, and Ursa Major I based on their recently determined star formation histories. We show that two single-age bursts cannot explain the observed [α/Fe] versus [Fe/H] distribution in these galaxies and that some self-enrichment is required within the first burst. An alternative scenario is modeled, in which star formation is continuous except for short interruptions when one or more supernovae temporarily blow the dense gas out from the center of the system. This model allows for self-enrichment and can reproduce the chemical abundances of the UFDs in which the second burst is only a trace population. We conclude that the most likely star formation history is one or two extended periods of star formation, with the first burst lasting for at least 100 Myr. As found in earlier work, the observed properties of UFDs can be explained by formation at a low mass (M{sub vir}∼10{sup 7} M{sub ⊙}), rather than being stripped remnants of much larger systems.

  19. Radiochronological Age of a Uranium Metal Sample from an Abandoned Facility

    SciTech Connect (OSTI)

    Meyers, L A; Williams, R W; Glover, S E; LaMont, S P; Stalcup, A M; Spitz, H B

    2012-03-16

    A piece of scrap uranium metal bar buried in the dirt floor of an old, abandoned metal rolling mill was analyzed using multi-collector inductively coupled plasma mass spectroscopy (MC-ICP-MS). The mill rolled uranium rods in the 1940s and 1950s. Samples of the contaminated dirt in which the bar was buried were also analyzed. The isotopic composition of uranium in the bar and dirt samples were both the same as natural uranium, though a few samples of dirt also contained recycled uranium; likely a result of contamination with other material rolled at the mill. The time elapsed since the uranium metal bar was last purified can be determined by the in-growth of the isotope {sup 230}Th from the decay of {sup 234}U, assuming that only uranium isotopes were present in the bar after purification. The age of the metal bar was determined to be 61 years at the time of this analysis and corresponds to a purification date of July 1950 {+-} 1.5 years.

  20. Extended main sequence turnoffs in intermediate-age star clusters: a correlation between turnoff width and early escape velocity

    SciTech Connect (OSTI)

    Goudfrooij, Paul; Kozhurina-Platais, Vera; Kalirai, Jason S.; Correnti, Matteo E-mail: verap@stsci.edu E-mail: correnti@stsci.edu; and others

    2014-12-10

    We present a color-magnitude diagram analysis of deep Hubble Space Telescope imaging of a mass-limited sample of 18 intermediate-age (1-2 Gyr old) star clusters in the Magellanic Clouds, including eight clusters for which new data were obtained. We find that all star clusters in our sample feature extended main-sequence turnoff (eMSTO) regions that are wider than can be accounted for by a simple stellar population (including unresolved binary stars). FWHM widths of the MSTOs indicate age spreads of 200-550 Myr. We evaluate the dynamical evolution of clusters with and without initial mass segregation. Our main results are (1) the fraction of red clump (RC) stars in secondary RCs in eMSTO clusters scales with the fraction of MSTO stars having pseudo-ages of ?1.35 Gyr; (2) the width of the pseudo-age distributions of eMSTO clusters is correlated with their central escape velocity v {sub esc}, both currently and at an age of 10 Myr. We find that these two results are unlikely to be reproduced by the effects of interactive binary stars or a range of stellar rotation velocities. We therefore argue that the eMSTO phenomenon is mainly caused by extended star formation within the clusters; and (3) we find that v {sub esc} ? 15 km s{sup 1} out to ages of at least 100 Myr for all clusters featuring eMSTOs, and v {sub esc} ? 12 km s{sup 1} at all ages for two lower-mass clusters in the same age range that do not show eMSTOs. We argue that eMSTOs only occur for clusters whose early escape velocities are higher than the wind velocities of stars that provide material from which second-generation stars can form. The threshold of 12-15 km s{sup 1} is consistent with wind velocities of intermediate-mass asymptotic giant branch stars and massive binary stars in the literature.

  1. STATUS REPORT FOR AGING STUDIES OF EPDM O-RING MATERIAL FOR THE H1616 SHIPPING PACKAGE

    SciTech Connect (OSTI)

    Stefek, T.; Daugherty, W.; Skidmore, E.

    2012-08-31

    This is an interim status report for tasks carried out per Task Technical Plan SRNL-STI-2011-00506. A series of tasks/experiments are being performed at the Savannah River National Laboratory to monitor the aging performance of ethylene propylene diene monomer (EPDM) Orings used in the H1616 shipping package. The data will support the technical basis to extend the annual maintenance of the EPDM O-rings in the H1616 shipping package and to predict the life of the seals at bounding service conditions. Current expectations are that the O-rings will maintain a seal at bounding normal temperatures in service (152 F) for at least 12 months. The baseline aging data review suggests that the EPDM O-rings are likely to retain significant mechanical properties and sealing force at bounding service temperatures to provide a service life of at least 2 years. At lower, more realistic temperatures, longer service life is likely. Parallel compression stress relaxation and vessel leak test efforts are in progress to further validate this assessment and quantify a more realistic service life prediction. The H1616 shipping package O-rings were evaluated for baseline property data as part of this test program. This was done to provide a basis for comparison of changes in material properties and performance parameters as a function of aging. This initial characterization was limited to physical and mechanical properties, namely hardness, thickness and tensile strength. These properties appear to be consistent with O-ring specifications. Three H1616-1 Containment Vessels were placed in test conditions and are aging at temperatures ranging from 160 to 300 F. The vessels were Helium leak-tested initially and have been tested at periodic intervals after cooling to room temperature to determine if they meet the criterion of leaktightness defined in ANSI standard N14.5-97 (< 1E-07 std cc air/sec at room temperature). To date, no leak test failures have occurred. The cumulative time at temperature ranges from 174 days for the 300 F vessel to 189 days for the 160 F vessel as of 8/1/2012. The compression stress-relaxation (CSR) behavior of H1616 shipping package O-rings is being evaluated to develop an aging model based on material properties. O-ring segments were initially aged at four temperatures (175 F, 235 F, 300 F and 350 F). These temperatures were selected to bound normal service temperatures and to challenge the seals within a reasonable aging period. Currently, samples aging at 300 F and 350 F have reached the mechanical failure point (end of life) which is defined in this study as 90% loss of initial sealing force. As a result, additional samples more recently began aging at {approx}270 F to provide additional data for the aging model. Aging and periodic leak testing of the full containment vessels, as well as CSR testing of O-ring segments is ongoing. Continued testing per the Task Technical Plan is recommended in order to validate the assumptions outlined in this status report and to quantify and validate the long-term performance of O-ring seals under actual service conditions.

  2. POPULATION PARAMETERS OF INTERMEDIATE-AGE STAR CLUSTERS IN THE LARGE MAGELLANIC CLOUD. III. DYNAMICAL EVIDENCE FOR A RANGE OF AGES BEING RESPONSIBLE FOR EXTENDED MAIN-SEQUENCE TURNOFFS

    SciTech Connect (OSTI)

    Goudfrooij, Paul; Kozhurina-Platais, Vera; Puzia, Thomas H.; Chandar, Rupali E-mail: verap@stsci.edu E-mail: rupali.chandar@utoledo.edu

    2011-08-10

    We present a new analysis of 11 intermediate-age (1-2 Gyr) star clusters in the Large Magellanic Cloud based on Hubble Space Telescope imaging data. Seven of the clusters feature main-sequence turnoff (MSTO) regions that are wider than can be accounted for by a simple stellar population, whereas their red giant branches (RGBs) indicate a single value of [Fe/H]. The star clusters cover a range in present-day mass from about 1 x 10{sup 4} M{sub sun} to 2 x 10{sup 5} M{sub sun}. We compare radial distributions of stars in the upper and lower parts of the MSTO region, and calculate cluster masses and escape velocities from the present time back to a cluster age of 10 Myr. Our main result is that for all clusters in our sample with estimated escape velocities v{sub esc} {approx}> 15 km s{sup -1} at an age of 10 Myr, the stars in the brightest half of the MSTO region are significantly more centrally concentrated than the stars in the faintest half and more massive RGB and asymptotic giant branch stars. This is not the case for clusters with v{sub esc} {approx}< 10 km s{sup -1} at an age of 10 Myr. We argue that the wide MSTO region of such clusters is caused mainly by a {approx}200-500 Myr range in the ages of cluster stars due to extended star formation within the cluster from material shed by first-generation stars featuring slow stellar winds. Dilution of this enriched material by accretion of ambient interstellar matter is deemed plausible if the spread of [Fe/H] in this ambient gas was very small when the second-generation stars were formed in the cluster.

  3. Managing aging effects on dry cask storage systems for extended long-term storage and transportation of used fuel - rev. 0

    SciTech Connect (OSTI)

    Chopra, O.K.; Diercks, D.; Fabian, R.; Ma, D.; Shah, V.; Tam, S.W.; Liu, Y.

    2012-07-06

    The cancellation of the Yucca Mountain repository program in the United States raises the prospect of extended long-term storage (i.e., >120 years) and deferred transportation of used fuel at operating and decommissioned nuclear power plant sites. Under U.S. federal regulations contained in Title 10 of the Code of Federal Regulations (CFR) 72.42, the initial license term for an Independent Spent Fuel Storage Installation (ISFSI) must not exceed 40 years from the date of issuance. Licenses may be renewed by the U.S. Nuclear Regulatory Commission (NRC) at the expiration of the license term upon application by the licensee for a period not to exceed 40 years. Application for ISFSI license renewals must include the following: (1) Time-limited aging analyses (TLAAs) that demonstrate that structures, systems, and components (SSCs) important to safety will continue to perform their intended function for the requested period of extended operation; and (2) a description of the aging management program (AMP) for management of issues associated with aging that could adversely affect SSCs important to safety. In addition, the application must also include design bases information as documented in the most recent updated final safety analysis report as required by 10 CFR 72.70. Information contained in previous applications, statements, or reports filed with the Commission under the license may be incorporated by reference provided that those references are clear and specific. The NRC has recently issued the Standard Review Plan (SRP) for renewal of used-fuel dry cask storage system (DCSS) licenses and Certificates of Compliance (CoCs), NUREG-1927, under which NRC may renew a specific license or a CoC for a term not to exceed 40 years. Both the license and the CoC renewal applications must contain revised technical requirements and operating conditions (fuel storage, surveillance and maintenance, and other requirements) for the ISFSI and DCSS that address aging effects that could affect the safe storage of the used fuel. The information contained in the license and CoC renewal applications will require NRC review to verify that the aging effects on the SSCs in DCSSs/ ISFSIs are adequately managed for the period of extended operation. To date, all of the ISFSIs located across the United States with more than 1,500 dry casks loaded with used fuel have initial license terms of 20 years; three ISFSIs (Surry, H.B. Robinson and Oconee) have received their renewed licenses for 20 years, and two other ISFSIs (Calvert Cliffs and Prairie Island) have applied for license renewal for 40 years. This report examines issues related to managing aging effects on the SSCs in DCSSs/ISFSIs for extended long-term storage and transportation of used fuels, following an approach similar to that of the Generic Aging Lessons Learned (GALL) report, NUREG-1801, for the aging management and license renewal of nuclear power plants. The report contains five chapters and an appendix on quality assurance for aging management programs for used-fuel dry storage systems. Chapter I of the report provides an overview of the ISFSI license renewal process based on 10 CFR 72 and the guidance provided in NUREG-1927. Chapter II contains definitions and terms for structures and components in DCSSs, materials, environments, aging effects, and aging mechanisms. Chapter III and Chapter IV contain generic TLAAs and AMPs, respectively, that have been developed for managing aging effects on the SSCs important to safety in the dry cask storage system designs described in Chapter V. The summary descriptions and tabulations of evaluations of AMPs and TLAAs for the SSCs that are important to safety in Chapter V include DCSS designs (i.e., NUHOMS{reg_sign}, HI-STORM 100, Transnuclear (TN) metal cask, NAC International S/T storage cask, ventilated storage cask (VSC-24), and the Westinghouse MC-10 metal dry storage cask) that have been and continue to be used by utilities across the country for dry storage of used fuel to date. The goal of this report is to help establish the technical basis for extended long-term storage and transportation of used fuel.

  4. Thermal aging modeling and validation on the Mo containing Fe-Cr-Ni alloys

    SciTech Connect (OSTI)

    Yang, Ying; Tan, Lizhen; Busby, Jeremy T.

    2015-04-01

    Thermodynamics of intermetallic phases in Fe-rich Fe-Cr-Ni-Mo alloys is critical knowledge to understand thermal aging effect on the phase stability of Mo-containing austenitic steels, which subsequently facilitates alloy design/improvement and degradation mitigation of these materials for reactor applications. Among the intermetallic phases, Chi (χ), Laves, and Sigma (σ) are often of concern because of their tendency to cause embrittlement of the materials. The focus of this study is thermal stability of the Chi and Laves phases as they were less studied compared to the Sigma phase. Coupled with thermodynamic modeling, thermal stability of intermetallic phases in Mo containing Fe-Cr-Ni alloys was investigated at 1000, 850 and 700 C for different annealing times. The morphologies, compositions and crystal structures of the precipitates of the intermetallic phases were carefully examined by scanning electron microscopy, electron probe microanalysis, X-ray diffraction, and transmission electron microscopy. Three key findings resulted from this study. First, the Chi phase is stable at high temperature, and with decreasing temperature it transforms into the Laves phase that is stable at low temperature. Secondly, Cr, Mo, Ni are soluble in both the Chi and Laves phases, with the solubility of Mo playing a major role in the relative stability of the intermetallic phases. Thirdly, in situ transformation from Chi phase to Laves phase was directly observed, which increased the local strain field, generated dislocations in the intermetallic phases, and altered the precipitate phase orientation relationship with the austenitic matrix. The thermodynamic models that were developed and validated were then applied to evaluating the effect of Mo on the thermal stability of intermetallic phases in type 316 and NF709 stainless steels.

  5. Examination of phase transformations and decomposition chemistry in thermally aged thin-film explosives

    SciTech Connect (OSTI)

    Erickson, K.L.; Trott, W.M.; Renlund, A.M.

    1993-09-01

    To develop predictive models for the response of weapon systems to abnormal thermal environments, such as cookoff, an improved understanding of temperature-dependent thermophysical phenomena (such as phase transformations) and decomposition chemistry in totally confined explosive samples is needed. It is particularly important to examine the effects of maintaining-intimate contact between the decomposition products and the remaining condensed-phase explosive during slow reaction at elevated temperatures since confinement of the decomposition products may significantly affect thermophysical phenomena and decomposition reaction rates. The purpose of this work has been to examine experimentally the effects on condensed-phase chemistry which result when decomposition products remain in intimate contact with the reacting explosive during isothermal aging experiments at temperatures below those of the DTA exotherm for the explosive. To provide confinement, minimize vapor space, and permit condensed-phase chemical analysis, experiments were done using thin-film samples of the explosive, which were pressed and sealed between two infrared-transmitting windows, so that condensed-phase chemistry could be monitored using infrared spectroscopy. Experiments were done with NC, HMX, HMX-NC composite, and RDX samples. Results from the experiments with NC showed that for some decomposition mechanisms, the reaction rates for confined samples compared favorably with published reaction rates from unconfined samples. However, the results also demonstrated that for other mechanisms, the reaction rates were significantly affected by confinement of the decomposition products. The experiments with HMX and RDX indicated that some decomposition occurred at temperatures well below the temperatures of the respective DTA exotherms, and the experiments with HMX-NC composite samples showed some interaction between NC and HMX at temperatures as low as 150{degrees}C.

  6. Analog morphocorrelation: new technique with implications for high-resolution absolute age dating

    SciTech Connect (OSTI)

    Arnold, A.J.; Parker, W.C.; Berggren, W.A.

    1986-05-01

    The conventional approach to increased biostratigraphic resolution involves identifying additional datum planes defined by discrete events. Multivariate techniques used to refine a conventional taxonomic zonal scheme offer no improvement in precision; however, since the characters on which the zonal boundaries are based often show continuous stratigraphic variation, they offer an opportunity for continuous stratigraphic correlation based on the stage of evolution. Morphometric analysis was conducted on two lineages: (1) the Globorotalia cibaoensis-G. crassaformis linage, using a reference section from the early Pliocene of the Rio Grande rise, spanning approximately 2.6 m.y.; and (2) the G. conoidea-G.inflata lineage, using a reference section from the late Miocene to the Holocene from the southwest Pacific, spanning approximately 8 m.y. Stepwise multiple regression of morphologic variates generated an equation with an age-prediction precision (95% confidence) of +/- 122 k.y. in the G. crassaformis lineage and +/- 463 k.y. in the G conoidea lineage (accuracy depends on calibration of absolute dates in the reference section and our knowledge of sedimentation rates over the measured interval). Using single-equation analog morphocorrelation, any sample overlapped by the reference lineage can be correlated, which reduce the need for repeated sampling in a search for discrete events. The authors demonstrate that analysis of continuous morphologic variation can increase stratigraphic precision with a few carefully chosen variables, and that analog morpho-correlation can yield absolute dates, rather than relative dates with quantified error. Any disadvantages inherent in analog morphocorrelation are also found in conventional biostratigraphic techniques, but are usually unquantified and unrecognized.

  7. Effects of Acclimation on Poststocking Dispersal and Physiological Condition of Age-1 Pallid Sturgeon

    SciTech Connect (OSTI)

    Oldenburg, Eric W.; Guy, Christopher S.; Cureton, Eli S.; Webb, Molly H.; Gardner, William M.

    2011-03-28

    A propagation program for pallid sturgeon Scaphirhynchus albus in the upper Missouri River was implemented by the U. S. Fish and Wildlife Service in 1997. Preliminary research indicated that many hatchery-reared pallid sturgeon were experiencing significant downstream poststocking dispersal, negatively affecting their recruitment. Therefore, the objective of this study was to evaluate the effects of acclimation to flow and site-specific physicochemical water conditions on poststocking dispersal and physiological condition of age-1 pallid sturgeon. Fish from three acclimation treatments were radio-tagged, released at two locations (Missouri River and Marias River), and monitored using passive telemetry stations. Marias treatment was acclimated to flow and site-specific physicochemical conditions, Bozeman treatment was acclimated to flow only, and traditional treatment had no acclimation (reared under traditional protocol). During both years fish released in the Missouri River dispersed less than fish released in the Marias River. In 2005, Marias treatment dispersed less and nearly twice as many fish remained in the Missouri River reach than traditional treatment. In 2006, pallid sturgeon dispersed similarly among treatments and fish remaining in the Missouri River reach were similar among all treatments. Differences in poststocking dispersal between years may be related to fin curl. Fin curl was present in all fish in 2005 and 27% of the fish in 2006. Pallid sturgeon from all treatments in both years had a greater affinity for the lower reaches of the Missouri River than the upper reaches. Thus, habitat at release site influenced poststocking dispersal more than acclimation treatment. No difference was observed in relative growth rate among treatments in 2006. However, acclimation to flow (i.e., exercise conditioning) may reduce liver fat content. Acclimation conditions used in this study may not benefit pallid sturgeon unless physiological maladies are present. Further, natural resource agencies need to consider stocking location carefully to reduce poststocking dispersal.

  8. LEVERAGING AGING MATERIALS DATA TO SUPPORT EXTENSION OF TRANSPORTATION SHIPPING PACKAGES SERVICE LIFE

    SciTech Connect (OSTI)

    Dunn, K.; Bellamy, S.; Daugherty, W.; Sindelar, R.; Skidmore, E.

    2013-08-18

    Nuclear material inventories are increasingly being transferred to interim storage locations where they may reside for extended periods of time. Use of a shipping package to store nuclear materials after the transfer has become more common for a variety of reasons. Shipping packages are robust and have a qualified pedigree for performance in normal operation and accident conditions but are only certified over an approved transportation window. The continued use of shipping packages to contain nuclear material during interim storage will result in reduced overall costs and reduced exposure to workers. However, the shipping package materials of construction must maintain integrity as specified by the safety basis of the storage facility throughout the storage period, which is typically well beyond the certified transportation window. In many ways, the certification processes required for interim storage of nuclear materials in shipping packages is similar to life extension programs required for dry cask storage systems for commercial nuclear fuels. The storage of spent nuclear fuel in dry cask storage systems is federally-regulated, and over 1500 individual dry casks have been in successful service up to 20 years in the US. The uncertainty in final disposition will likely require extended storage of this fuel well beyond initial license periods and perhaps multiple re-licenses may be needed. Thus, both the shipping packages and the dry cask storage systems require materials integrity assessments and assurance of continued satisfactory materials performance over times not considered in the original evaluation processes. Test programs for the shipping packages have been established to obtain aging data on materials of construction to demonstrate continued system integrity. The collective data may be coupled with similar data for the dry cask storage systems and used to support extending the service life of shipping packages in both transportation and storage.

  9. Structural effects of protein aging: Terminal marking by deamidation in human triosephosphate isomerase

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Torres-Larios, Alfredo; Enríquez-Flores, Sergio; Méndez, Sara -Teresa; Castillo-Villanueva, Adriana; Gómez-Manzo, Saúl; Velázquez, Gabriel López-; Marcial-Quino, Jaime; Torres-Arroyo, Angélica; García-Torres, Itzhel; Reyes-Vivas, Horacio; et al

    2015-04-17

    Deamidation, the loss of the ammonium group of asparagine and glutamine to form aspartic and glutamic acid, is one of the most commonly occurring post-translational modifications in proteins. Since deamidation rates are encoded in the protein structure, it has been proposed that they can serve as molecular clocks for the timing of biological processes such as protein turnover, development and aging. Despite the importance of this process, there is a lack of detailed structural information explaining the effects of deamidation on the structure of proteins. Here, we studied the effects of deamidation on human triosephosphate isomerase (HsTIM), an enzyme formore » which deamidation of N15 and N71 has been long recognized as the signal for terminal marking of the protein. Deamidation was mimicked by site directed mutagenesis; thus, three mutants of HsTIM (N15D, N71D and N15D/N71D) were characterized. The results show that the N71D mutant resembles, structurally and functionally, the wild type enzyme. In contrast, the N15D mutant displays all the detrimental effects related to deamidation. The N15D/N71D mutant shows only minor additional effects when compared with the N15D mutation, supporting that deamidation of N71 induces negligible effects. The crystal structures show that, in contrast to the N71D mutant, where minimal alterations are observed, the N15D mutation forms new interactions that perturb the structure of loop 1 and loop 3, both critical components of the catalytic site and the interface of HsTIM. Based on a phylogenetic analysis of TIM sequences, we propose the conservation of this mechanism for mammalian TIMs.« less

  10. Weakest solar wind of the space age and the current 'MINI' solar maximum

    SciTech Connect (OSTI)

    McComas, D. J.; Angold, N.; Elliott, H. A.; Livadiotis, G.; Schwadron, N. A.; Smith, C. W.; Skoug, R. M.

    2013-12-10

    The last solar minimum, which extended into 2009, was especially deep and prolonged. Since then, sunspot activity has gone through a very small peak while the heliospheric current sheet achieved large tilt angles similar to prior solar maxima. The solar wind fluid properties and interplanetary magnetic field (IMF) have declined through the prolonged solar minimum and continued to be low through the current mini solar maximum. Compared to values typically observed from the mid-1970s through the mid-1990s, the following proton parameters are lower on average from 2009 through day 79 of 2013: solar wind speed and beta (?11%), temperature (?40%), thermal pressure (?55%), mass flux (?34%), momentum flux or dynamic pressure (?41%), energy flux (?48%), IMF magnitude (?31%), and radial component of the IMF (?38%). These results have important implications for the solar wind's interaction with planetary magnetospheres and the heliosphere's interaction with the local interstellar medium, with the proton dynamic pressure remaining near the lowest values observed in the space age: ?1.4 nPa, compared to ?2.4 nPa typically observed from the mid-1970s through the mid-1990s. The combination of lower magnetic flux emergence from the Sun (carried out in the solar wind as the IMF) and associated low power in the solar wind points to the causal relationship between them. Our results indicate that the low solar wind output is driven by an internal trend in the Sun that is longer than the ?11 yr solar cycle, and they suggest that this current weak solar maximum is driven by the same trend.

  11. Microfaunal evidence of age and depositional environments of the Cerro Prieto section (Plio-Pleistocene), Baja California, Mexico

    SciTech Connect (OSTI)

    Ingle, J.C. Jr.

    1982-01-01

    Microfossils including benthic and planktic foraminifera, ostracodes, calcareous algae, fish skeletal material, and fragments of pelecypods were found in 14 core samples from depths of 185 to 1952 m in the Cerro Prieto geothermal field, providing evidence of both the age and depositional history of sediments comprising the 3000-m-thick Pliocene and Pleistocene section in this area. Ostracodes of brackish water and marine origin constitute the most common microfossils present in this sequence occurring in 8 samples; in situ littoral and neritic species of benthic foraminifera occur in 5 samples with planktic species present in 2 samples. Distributional patterns of ostracodes and foraminifera together with previously analyzed lithofacies (Lyons and van de Kamp, 1980) indicate that the Cerro Prieto section represents an intertonguing complex of alluvial, deltaic, estuarine, and shallow marine environments deposited along the front of the Colorado River delta as it prograded across the Salton Trough during Pliocene and Pleistocene time. Foraminiferal evidence indicates that a sand and shale unit commonly present at depths between 700 and 1100 m represents a significant mid-Pleistocene marine incursion in the Cerro Prieto area. Tentative correlation of the Cerro Prieto section with the well dated Palm Springs Formation of the Imperial Valley, California area suggests that the Pliocene/Pleistocene boundary occurs at a depth of approximately 2000 m in the area of well M-93. Reworked specimens of Cretaceous foraminifera and fragments of the Cretaceous pelecypod Inoceramus were found in five samples further substantiating the Colorado Plateau provenance of a significant portion of the Colorado River deltaic sediments in the Cerro Prieto area.

  12. Evaluating the Effects of Aging on Electronic Instrument and Control Circuit Boards and Components in Nuclear Power Plants

    SciTech Connect (OSTI)

    G. William Hannaman; C. Dan Wilkinson

    2005-05-15

    The report describes potentially useful techniques for monitoring the aging of I&C boards. The techniques have been grouped into: periodic testing, reliability modeling, resistance measures, signal comparison, eternal measures, and internal measures, each representing distinct theoretical approaches to detection and evaluation.

  13. Aging characteristics of electron beam and gas tungsten arc fusion zones of Al-Cu-Li alloy 2090

    SciTech Connect (OSTI)

    Sunwoo, A.J. . Center for Advanced Materials); Morris, J.W. Jr. . Dept of Materials Science and Engineering)

    1991-04-01

    A transmission electron microscopy (TEM) investigation of the electron beam (EB) and gas tungsten arc (GTA) fusion zones of 2090 indicates that in both the as-welded and aged conditions, the EB and GTA fusion zones lack the volume fraction and the homogeneity of strengthening precipitates found in the base metal. In the underaged and peak-aged conditions, the [delta][prime] phase is the primary strengthener, the volume fraction of T[sub 1] present being too low to be effective. The T[sub 1] precipitates are found either in the vicinity of other inclusions or at the dendrite boundaries. As the strength increases with postweld aging, the elongation decreased to 1%. The presence of the boundary phases and Cu- and Cl-containing inclusions at the boundaries leads to poor elongation. The joint efficiencies of the peak-aged EB and GTA weldments (EBWs and GTAWs, respectively) are 75 and 55% at 293 K and 75 and 50% at 77 K, respectively. Both EBWs and GTAWs have relatively low elongations.

  14. Petrography, age, and paleomagnetism of basaltic lava flows in coreholes at Test Area North (TAN), Idaho National Engineering Laboratory

    SciTech Connect (OSTI)

    Lanphere, M.A.; Champion, D.E.; Kuntz, M.A.

    1994-12-31

    The petrography, age, and paleomagnetism were determined on basalt from 21 lava flows comprising about 1,700 feet of core from two coreholes (TAN CH No. 1 and TAN CH No. 2) in the Test Area North (TAN) area of the Idaho National Engineering Laboratory (INEL). Paleomagnetic studies were made on two additional cores from shallow coreholes in the TAN area. K-Ar ages and paleomagnetism also were determined on nearby surface outcrops of Circular Butte. Paleomagnetic measurements were made on 416 samples from four coreholes and on a single site in surface lava flows of Circular Butte. K-Ar ages were measured on 9 basalt samples from TAN CH No. 1 and TAN CH No. 2 and one sample from Circular Butte. K-Ar ages ranged from 1.044 Ma to 2.56 Ma. All of the samples have reversed magnetic polarity and were erupted during the Matuyama Reversed Polarity Epoch. The purpose of investigations was to develop a three-dimensional stratigraphic framework for geologic and hydrologic studies including potential volcanic hazards to facilities at the INEL and movement of radionuclides in the Snake River Plain aquifer.

  15. THE INTERIOR STRUCTURE CONSTANTS AS AN AGE DIAGNOSTIC FOR LOW-MASS, PRE-MAIN-SEQUENCE DETACHED ECLIPSING BINARY STARS

    SciTech Connect (OSTI)

    Feiden, Gregory A.; Dotter, Aaron E-mail: aaron.dotter@gmail.com

    2013-03-10

    We propose a novel method for determining the ages of low-mass, pre-main-sequence stellar systems using the apsidal motion of low-mass detached eclipsing binaries. The apsidal motion of a binary system with an eccentric orbit provides information regarding the interior structure constants of the individual stars. These constants are related to the normalized stellar interior density distribution and can be extracted from the predictions of stellar evolution models. We demonstrate that low-mass, pre-main-sequence stars undergoing radiative core contraction display rapidly changing interior structure constants (greater than 5% per 10 Myr) that, when combined with observational determinations of the interior structure constants (with 5%-10% precision), allow for a robust age estimate. This age estimate, unlike those based on surface quantities, is largely insensitive to the surface layer where effects of magnetic activity are likely to be most pronounced. On the main sequence, where age sensitivity is minimal, the interior structure constants provide a valuable test of the physics used in stellar structure models of low-mass stars. There are currently no known systems where this technique is applicable. Nevertheless, the emphasis on time domain astronomy with current missions, such as Kepler, and future missions, such as LSST, has the potential to discover systems where the proposed method will be observationally feasible.

  16. The effect of thermal aging on the thermal conductivity of plasma sprayed and EB-PVD thermal barrier coatings

    SciTech Connect (OSTI)

    Dinwiddie, R.B.; Beecher, S.C.; Porter, W.D.; Nagaraj, B.A.

    1996-05-01

    Thermal barrier coatings (TBCs) applied to the hot gas components of turbine engines lead to enhanced fuel efficiency and component reliability. Understanding the mechanisms which control the thermal transport behavior of the TBCs is of primary importance. Electron beam-physical vapor deposition (EV-PVD) and air plasma spraying (APS) are the two most commonly used coating techniques. These techniques produce coatings with unique microstructures which control their performance and stability. The density of the APS coatings was controlled by varying the spray parameters. The low density APS yttria-partially stabilized zirconia (yttria-PSZ) coatings yielded a thermal conductivity that is lower than both the high density APS coatings and the EB-PVD coatings. The thermal aging of both fully and partially stabilized zirconia are compared. The thermal conductivity of the coatings permanently increases upon exposure to high temperatures. These increases are attributed to microstructural changes within the coatings. This increase in thermal conductivity can be modeled using a relationship which depends on both the temperature and time of exposure. Although the EB-PVD coatings are less susceptible to thermal aging effects, results suggest that they typically have a higher thermal conductivity than APS coatings before thermal aging. The increases in thermal conductivity due to thermal aging for plasma sprayed partially stabilized zirconia have been found to be less than for plasma sprayed fully stabilized zirconia coatings.

  17. A Bayesian Modeling Approach for Estimation of a Shape-Free Groundwater Age Distribution using Multiple Tracers

    SciTech Connect (OSTI)

    Massoudieh, Arash; Visser, Ate; Sharifi, Soroosh; Broers, Hans Peter

    2013-10-15

    The mixing of groundwaters with different ages in aquifers, groundwater age is more appropriately represented by a distribution rather than a scalar number. To infer a groundwater age distribution from environmental tracers, a mathematical form is often assumed for the shape of the distribution and the parameters of the mathematical distribution are estimated using deterministic or stochastic inverse methods. We found that the prescription of the mathematical form limits the exploration of the age distribution to the shapes that can be described by the selected distribution. In this paper, the use of freeform histograms as groundwater age distributions is evaluated. A Bayesian Markov Chain Monte Carlo approach is used to estimate the fraction of groundwater in each histogram bin. This method was able to capture the shape of a hypothetical gamma distribution from the concentrations of four age tracers. The number of bins that can be considered in this approach is limited based on the number of tracers available. The histogram method was also tested on tracer data sets from Holten (The Netherlands; 3H, 3He, 85Kr, 39Ar) and the La Selva Biological Station (Costa-Rica; SF 6, CFCs, 3H, 4He and 14C), and compared to a number of mathematical forms. According to standard Bayesian measures of model goodness, the best mathematical distribution performs better than the histogram distributions in terms of the ability to capture the observed tracer data relative to their complexity. Among the histogram distributions, the four bin histogram performs better in most of the cases. The Monte Carlo simulations showed strong correlations in the posterior estimates of bin contributions, indicating that these bins cannot be well constrained using the available age tracers. The fact that mathematical forms overall perform better than the freeform histogram does not undermine the benefit of the freeform approach, especially for the cases where a larger amount of observed data is available and when the real groundwater distribution is more complex than can be represented by simple mathematical forms.

  18. Nuclear Energy Plant Optimization (NEPO) final report on aging and condition monitoring of low-voltage cable materials.

    SciTech Connect (OSTI)

    Assink, Roger Alan; Gillen, Kenneth Todd; Bernstein, Robert

    2005-11-01

    This report summarizes results generated on a 5-year cable-aging program that constituted part of the Nuclear Energy Plant Optimization (NEPO) program, an effort cosponsored by the U. S. Department of Energy (DOE) and the Electric Power Research Institute (EPRI). The NEPO cable-aging effort concentrated on two important issues involving the development of better lifetime prediction methods as well as the development and testing of novel cable condition-monitoring (CM) techniques. To address improved life prediction methods, we first describe the use of time-temperature superposition principles, indicating how this approach improves the testing of the Arrhenius model by utilizing all of the experimentally generated data instead of a few selected and processed data points. Although reasonable superposition is often found, we show several cases where non-superposition is evident, a situation that violates the constant acceleration assumption normally used in accelerated aging studies. Long-term aging results over extended temperature ranges allow us to show that curvature in Arrhenius plots for elongation is a common occurrence. In all cases the curvature results in a lowering of the Arrhenius activation energy at lower temperatures implying that typical extrapolation of high temperature results over-estimates material lifetimes. The long-term results also allow us to test the significance of extrapolating through the crystalline melting point of semi-crystalline materials. By utilizing ultrasensitive oxygen consumption (UOC) measurements, we show that it is possible to probe the low temperature extrapolation region normally inaccessible to conventional accelerated aging studies. This allows the quantitative testing of the often-used Arrhenius extrapolation assumption. Such testing indicates that many materials again show evidence of ''downward'' curvature (E{sub a} values drop as the aging temperature is lowered) consistent with the limited elongation results and many literature results. It is also shown how the UOC approach allows the probing of temperatures that cross through the crystalline melting point region of semi-crystalline materials such as XLPO and EPR cable insulations. New results on combined environment aging of neoprene and hypalon cable jacketing materials are presented and offer additional evidence in support of our time-temperature-dose rate (t-T-DR) superposition approach that had been used successfully in the past for such situations.

  19. A Bayesian Modeling Approach for Estimation of a Shape-Free Groundwater Age Distribution using Multiple Tracers

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Massoudieh, Arash; Visser, Ate; Sharifi, Soroosh; Broers, Hans Peter

    2013-10-15

    The mixing of groundwaters with different ages in aquifers, groundwater age is more appropriately represented by a distribution rather than a scalar number. To infer a groundwater age distribution from environmental tracers, a mathematical form is often assumed for the shape of the distribution and the parameters of the mathematical distribution are estimated using deterministic or stochastic inverse methods. We found that the prescription of the mathematical form limits the exploration of the age distribution to the shapes that can be described by the selected distribution. In this paper, the use of freeform histograms as groundwater age distributions is evaluated.more » A Bayesian Markov Chain Monte Carlo approach is used to estimate the fraction of groundwater in each histogram bin. This method was able to capture the shape of a hypothetical gamma distribution from the concentrations of four age tracers. The number of bins that can be considered in this approach is limited based on the number of tracers available. The histogram method was also tested on tracer data sets from Holten (The Netherlands; 3H, 3He, 85Kr, 39Ar) and the La Selva Biological Station (Costa-Rica; SF 6, CFCs, 3H, 4He and 14C), and compared to a number of mathematical forms. According to standard Bayesian measures of model goodness, the best mathematical distribution performs better than the histogram distributions in terms of the ability to capture the observed tracer data relative to their complexity. Among the histogram distributions, the four bin histogram performs better in most of the cases. The Monte Carlo simulations showed strong correlations in the posterior estimates of bin contributions, indicating that these bins cannot be well constrained using the available age tracers. The fact that mathematical forms overall perform better than the freeform histogram does not undermine the benefit of the freeform approach, especially for the cases where a larger amount of observed data is available and when the real groundwater distribution is more complex than can be represented by simple mathematical forms.« less

  20. Lipoic acid entrains the hepatic circadian clock and lipid metabolic proteins that have been desynchronized with advanced age

    SciTech Connect (OSTI)

    Keith, Dove; Finlay, Liam; Butler, Judy; Gmez, Luis; Smith, Eric; Moreau, Rgis; Hagen, Tory

    2014-07-18

    Highlights: 24 month old rats were supplemented with 0.2% lipoic acid in the diet for 2 weeks. Lipoic acid shifts phase of core circadian clock proteins. Lipoic acid corrects age-induced desynchronized lipid metabolism rhythms. - Abstract: It is well established that lipid metabolism is controlled, in part, by circadian clocks. However, circadian clocks lose temporal precision with age and correlates with elevated incidence in dyslipidemia and metabolic syndrome in older adults. Because our lab has shown that lipoic acid (LA) improves lipid homeostasis in aged animals, we hypothesized that LA affects the circadian clock to achieve these results. We fed 24 month old male F344 rats a diet supplemented with 0.2% (w/w) LA for 2 weeks prior to sacrifice and quantified hepatic circadian clock protein levels and clock-controlled lipid metabolic enzymes. LA treatment caused a significant phase-shift in the expression patterns of the circadian clock proteins Period (Per) 2, Brain and Muscle Arnt-Like1 (BMAL1), and Reverse Erythroblastosis virus (Rev-erb) ? without altering the amplitude of protein levels during the light phase of the day. LA also significantly altered the oscillatory patterns of clock-controlled proteins associated with lipid metabolism. The level of peroxisome proliferator-activated receptor (PPAR) ? was significantly increased and acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS) were both significantly reduced, suggesting that the LA-supplemented aged animals are in a catabolic state. We conclude that LA remediates some of the dyslipidemic processes associated with advanced age, and this mechanism may be at least partially through entrainment of circadian clocks.

  1. Superconductivity at Dawn of the Iron Age (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    (Johns Hopkins University) Publication Date: 2010-03-03 OSTI Identifier: 1017174 DOE Contract Number: AC02-07CH11359 Resource Type: Conference Resource Relation: Conference: Fermilab Colloquia, Fermi National Accelerator Laboratory (FNAL), Batvia, Illinois (United States), presented on March 03, 2010 Research Org: FNAL (Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)) Sponsoring Org: USDOE Office of Science (SC) Country of Publication: United States Language: English

  2. Superconductivity at Dawn of the Iron Age (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Johns Hopkins University, Baltimore, Maryland, United States Publication Date: 2010-03-03 OSTI Identifier: 987784 DOE Contract Number: AC02-07CH11359 Resource Type: Conference Resource Relation: Conference: Fermilab Colloquia, Fermi National Accelerator Laboratory (FNAL), Batvia, Illinois (United States), presented on March 03, 2010 Publisher: Fermi Colloquia Online Research Org: FNAL (Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)) Sponsoring Org: USDOE Office of

  3. Superconductivity at Dawn of the Iron Age (Conference) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Country of Publication: United States Language: English Subject: 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND ...

  4. Round-robin 230Th–234U age dating of bulk uranium for nuclear forensics

    SciTech Connect (OSTI)

    Gaffney, Amy M.; Hubert, Amélie; Kinman, William S.; Magara, Masaaki; Okubo, Ayako; Pointurier, Fabien; Schorzman, Kerri C.; Steiner, Robert E.; Williams, Ross W.

    2015-07-30

    In an inter-laboratory measurement comparison study, four laboratories determined 230Th–234U model ages of uranium certified reference material NBL U050 using isotope dilution mass spectrometry. The model dates determined by the participating laboratories range from 9 March 1956 to 19 October 1957, and are indistinguishable given the associated measurement uncertainties. As a result, these model ages are concordant with to slightly older than the known production age of NBL U050.

  5. Determining Remaining Useful Life of Aging Cables in Nuclear Power Plants – Interim Study FY13

    SciTech Connect (OSTI)

    Simmons, Kevin L.; Fifield, Leonard S.; Westman, Matthew P.; Ramuhalli, Pradeep; Pardini, Allan F.; Tedeschi, Jonathan R.; Jones, Anthony M.

    2013-09-27

    The most important criterion for cable performance is its ability to withstand a design-basis accident. With nearly 1000 km of power, control, instrumentation, and other cables typically found in an NPP, it would be a significant undertaking to inspect all of the cables. Degradation of the cable jacket, electrical insulation, and other cable components is a key issue that is likely to affect the ability of the currently installed cables to operate safely and reliably for another 20 to 40 years beyond the initial operating life. The development of one or more nondestructive evaluation (NDE) techniques and supporting models that could assist in determining the remaining life expectancy of cables or their current degradation state would be of significant interest. The ability to nondestructively determine material and electrical properties of cable jackets and insulation without disturbing the cables or connections has been deemed essential. Currently, the only technique accepted by industry to measure cable elasticity (the gold standard for determining cable insulation degradation) is the indentation measurement. All other NDE techniques are used to find flaws in the cable and do not provide information to determine the current health or life expectancy. There is no single NDE technique that can satisfy all of the requirements needed for making a life-expectancy determination, but a wide range of methods have been evaluated for use in NPPs as part of a continuous evaluation program. The commonly used methods are indentation and visual inspection, but these are only suitable for easily accessible cables. Several NDE methodologies using electrical techniques are in use today for flaw detection but there are none that can predict the life of a cable. There are, however, several physical and chemical ptoperty changes in cable insulation as a result of thermal and radiation damage. In principle, these properties may be targets for advanced NDE methods to provide early warning of aging and degradation. Examples of such key indicators include changes in chemical structure, mechanical modulus, and dielectric permittivity. While some of these indicators are the basis of currently used technologies, there is a need to increase the volume of cable that may be inspected with a single measurement, and if possible, to develop techniques for in-situ inspection (i.e., while the cable is in operation). This is the focus of the present report.

  6. Carbon-enhanced metal-poor stars: relics from the dark ages

    SciTech Connect (OSTI)

    Cooke, Ryan J.; Madau, Piero

    2014-08-20

    We use detailed nucleosynthesis calculations and a realistic prescription for the environment of the first stars to explore the first episodes of chemical enrichment that occurred during the dark ages. Based on these calculations, we propose a novel explanation for the increased prevalence of carbon-enhanced metal-poor (CEMP) stars with decreasing Fe abundance: the observed chemistry for the most metal-poor Galactic halo stars is the result of an intimate link between the explosions of the first stars and their host minihalo's ability to retain its gas. Specifically, high-energy supernovae produce a near solar ratio of C/Fe, but are effective in evacuating the gas from their host minihalo, thereby suppressing the formation of a second generation of stars. On the other hand, minihalos that host low-energy supernovae are able to retain their gas and form a second stellar generation, but, as a result, the second stars are born with a supersolar ratio of C/Fe. Our models are able to accurately reproduce the observed distributions of [C/Fe] and [Fe/H], as well as the fraction of CEMP stars relative to non-CEMP stars as a function of [Fe/H] without any free parameters. We propose that the present lack of chemical evidence for very massive stars (≳ 140 M {sub ☉}) that ended their lives as a highly energetic pair-instability supernova does not imply that such stars were rare or did not exist; the chemical products of these very massive first stars may have been evacuated from their host minihalos and were never incorporated into subsequent generations of stars. Finally, our models suggest that the most Fe-poor stars currently known may have seen the enrichment from a small multiple of metal-free stars, and need not have been exclusively enriched by a solitary first star. These calculations also add further support to the possibility that some of the surviving dwarf satellite galaxies of the Milky Way are the relics of the first galaxies.

  7. Short term aging of LaNi{sub 4.25}Al{sub 0.75} tritide storage material

    SciTech Connect (OSTI)

    Holder, J.S.

    1994-10-01

    In support of the Tritium Facilities at the Savannah River Site (SRS), the Tritium Exposure Program (TEP) was initiated in 1986 to investigate the effects of tritium aging on metal hydride materials used in tritium processing applications. The primary material selected for tritium storage was the substituted LaNi{sub 5} alloy, LaNi{sub 4.25}Al{sub 0.75} (LANA.75). The substitution of Al for Ni served to lower the plateau pressure of the tritide, and to stabilize the material to cycling and tritium aging effects. The sub-atmospheric plateau pressure, of LANA.75 tritide at room temperature, made it a safe tritium storage medium, and the tritium aging effects were reduced from that of LaNi{sub 5} tritide, but not eliminated. LANA.75 tritides retain the {sup 3}He decay product of absorbed tritium in the metal lattice. As the concentration of {sup 3}He grows, the lattice becomes strained due to the insoluble species. This strain is manifest in tritium aging effects. These effects include (1) a decrease in the equilibrium plateau pressure, (2) an increase in the plateau slope, (3) a reduction in the reversible storage capacity, and (4) the evolution of a tritium heel. The long term aging effects have been studied over the years, however the short term (less than one year) tritium aging effects have not been investigated until now. The acquisition of desorption isotherms at more than one temperature allows the thermodynamic parameters of change in enthalpy, {Delta}H, and change in entropy, {Delta}S, for the {beta}-{alpha} phase transition of the metal tritide to be determined. These parameters are related to the equilibrium pressure, P, and the isothermal temperature, T, through the following relation: where R is the gas constant, and the factor of 1/2 yields results per mole of atomic tritium. A van`t Hoff plot of 1/2 Ln(P) versus 1/T may be fitted to a straight line, with the slope and intercept used to determine {Delta}H and {Delta}S through equation.

  8. Age- and sex-related differences of organic anion-transporting polypeptide gene expression in livers of rats

    SciTech Connect (OSTI)

    Hou, Wei-Yu; Xu, Shang-Fu; Zhu, Qiong-Ni; Lu, Yuan-Fu; Cheng, Xing-Guo; Liu, Jie

    2014-10-15

    Organic anion-transporting polypeptides (Oatps) play important roles in transporting endogenous substances and xenobiotics into the liver and are implicated in drug-drug interactions. Many factors could influence their expression and result in alterations in drug disposition, efficacy and toxicity. This study was aimed to examine the development-, aging-, and sex-dependent Oatps expression in livers of rats. The livers from SD rats during development (− 2, 1, 7, 14, 21, 28, 35, and 60 d) and aging (60, 180, 540 and/or 800 d) were collected and total RNAs were extracted, purified, and subjected to real-time PCR analysis. Total proteins were extracted for western-blot analysis. Results showed that Oatp1a1, Oatp1a4, Oatp1a5 and Oatp1b2 were all hardly detectable in fetal rat livers, low at birth, rapidly increased after weaning (21 d), and reached the peak at 60 d. The Oatps remained stable during the age between 60–180 d, and decreased at elderly (540 and/or 800 d). After birth, Oatp1a1, Oatp1a4, and Oatp1b2 were all highly expressed in liver, in contrast, Oatp1a5 expression was low. Oatp expressions are male-predominant in rat livers. In the livers of aged rats, the Oatp expression decreased and shared a consistent ontogeny pattern at the mRNA and protein level. In conclusion, this study showed that in rat liver, Oatp1a1, Oatp1a4, Oatp1a5 and Oatp1b2 gene expressions are influenced by age and gender, which could provide a basis of individual variation in drug transport, metabolism and toxicity in children, elderly and women. - Highlights: • Oatp1a1, Oatp1a4, Oatp1a5 and Oatp1b2 expression in livers of rats. • Ontogenic changes of Oatps at − 2, 1, 7, 14, 21, 28, 35, and 60 days. • Age-related changes of Oatps at 60, 180, 540, and 800 days. • Sex-difference of Oatps at the both mRNA and protein levels.

  9. Aging Behavior of Viton{sup R} O-Ring Seals in the 9975 Shipping Package - 12594

    SciTech Connect (OSTI)

    Skidmore, T. Eric; Daugherty, William L.; Hoffman, Elizabeth N.; Dunn, Kerry A.; Stephen Bellamy, J.; Shuler, James M.

    2012-07-01

    The Savannah River Site (SRS) is storing plutonium (Pu) materials in the K-Area Materials Storage (KAMS) facility. The Pu materials were packaged according to the DOE-STD-3013 standard and shipped to the SRS in Type B 9975 packages. The robust 9975 shipping package was not designed for long-term product storage, but it is a specified part of the storage configuration and the KAMS facility safety basis credits the 9975 design with containment. Within the 9975 package, nested stainless steel containment vessels are closed with dual O-ring seals based on Viton{sup R} GLT or GLT-S fluoro-elastomer. The aging behavior of the O-ring compounds is being studied to provide the facility with advanced notice of nonconformance and to develop life prediction models. A combination of field surveillance, leak testing of surrogate fixtures aged at bounding service temperatures, and accelerated-aging methodologies based on compression stress-relaxation and oxygen consumption analysis is being used to evaluate seal performance. A summary of the surveillance program relative to seal aging behavior is presented. The aging behavior of fluoro-elastomer seals based on Viton{sup R} GLT and GLT-S is being studied to develop life prediction models in support of long-term storage of plutonium materials in the 9975 shipping packages at the Savannah River Site. Field surveillance data in combination with accelerated-aging data suggest a significant lifetime for the seals. Typical storage conditions are not anticipated to challenge the leak-tightness of the seals for many years. Early life prediction models based on compression stress relaxation indicate a seal lifetime of ?12 years at the maximum service temperature predicted (93 deg. C). Seal lifetimes at lower, more realistic conditions are likely significantly longer. Service life predictions based on CSR data are thus far conservative relative to predictions based on time to leakage failure. Surveillance data on packages examined after 6 years in storage show only minor compression set of the O-rings and no significant degradation. Surveillance and testing will continue as needed to validate and refine life prediction models. (authors)

  10. Management of the aging of critical safety-related concrete structures in light-water reactor plants

    SciTech Connect (OSTI)

    Naus, D.J.; Oland, C.B. ); Arndt, E.G. )

    1990-01-01

    The Structural Aging Program has the overall objective of providing the USNRC with an improved basis for evaluating nuclear power plant safety-related structures for continued service. The program consists of a management task and three technical tasks: materials property data base, structural component assessment/repair technology, and quantitative methodology for continued-service determinations. Objectives, accomplishments, and planned activities under each of these tasks are presented. Major program accomplishments include development of a materials property data base for structural materials as well as an aging assessment methodology for concrete structures in nuclear power plants. Furthermore, a review and assessment of inservice inspection techniques for concrete materials and structures has been complete, and work on development of a methodology which can be used for performing current as well as reliability-based future condition assessment of concrete structures is well under way. 43 refs., 3 tabs.

  11. Cadmium effect on microsomal drug-metabolizing enzyme activity in rat livers with respect to differences in age and sex

    SciTech Connect (OSTI)

    Ando, M.

    1982-04-01

    The effect of cadmium on the hepatic microsomal drug-metabolizing enzyme system was investigated. Cadmium chloride caused the conversion of cytochrome P-450 to P-420 in rat liver microsomes. The destruction of cytochrome P-450 by cadmium caused the reduction of microsomal drug-metabolizing enzyme activity and prolonged the pentobarbital sleeping time. There is a sex-related difference in the ability of cadmium to inhibit the hepatic drug metabolism in rats: male rats are more sensitive to cadmium than females. The effective period when cadmium prolonged their sleep depended upon the age of rats; older rats were more sensitive to cadmium than younger ones. The maximum increase of sleeping time depended upon the dose level of cadium, and the rate constant of the equations seems to depend upon the age of the animals.

  12. Auger electron spectroscopy for the determination of sex and age related Ca/P ratio at different bone sites

    SciTech Connect (OSTI)

    Balatsoukas, Ioannis; Kourkoumelis, Nikolaos; Tzaphlidou, Margaret

    2010-10-15

    The Ca/P ratio of normal cortical and trabecular rat bone was measured by Auger electron spectroscopy (AES). Semiquantitative analysis was carried out using ratio techniques to draw conclusions on how age, sex and bone site affect the relative composition of calcium and phosphorus. Results show that Ca/P ratio is not sex dependent; quite the opposite, bone sites exhibit variations in elemental stoichiometry where femoral sections demonstrate higher Ca/P ratio than rear and front tibias. Age-related changes are more distinct for cortical bone in comparison with the trabecular bone. The latter's Ca/P ratio remains unaffected from all the parameters under study. This study confirms that AES is able to successfully quantify bone mineral main elements when certain critical points, related to the experimental conditions, are addressed effectively.

  13. Effects of aging and oxidation of palladized iron embedded in activated carbon on the dechlorination of 2-chlorobiphenyl

    SciTech Connect (OSTI)

    Hyeok Choi; Souhail R. Al-Abed; Shirish Agarwal

    2009-06-15

    Reactive activated carbon (RAC) impregnated with palladized iron has been developed to effectively treat polychlorinated biphenyls (PCBs) in the environment by coupling adsorption and dechlorination of PCBs. In this study, we addressed the dechlorination reactivity and capacity of RAC toward aqueous 2-chlorobiphenyl (2-ClBP), and its aging and longevity under various oxidizing environments. RAC containing 14.4% Fe and 0.68% Pd used in this study could adsorb 122.6 mg 2-ClBP/g RAC, and dechlorinate 56.5 mg 2-ClBP/g RAC which corresponds to 12% (yield) of its estimated dechlorination capacity. Due to Fe0 oxidation to form oxide passivating layers, Fe{sub 2}O{sub 3}/Fe{sub 3}O{sub 4} (oxide-water interface) and FeOOH/FeO (oxide-metal interface), RAC reactivity decreased progressively over aging under N{sub 2} < H{sub 2}O + N{sub 2} < H{sub 2}O + O{sub 2} conditions. Considering nanoscale Fe/Pd corrosion chemistry, the decline was quite slow at only 5.6%, 19.5%, and 32.5% over one year, respectively. Dissolved oxygen played a crucial role in enhancing 2-ClBP adsorption but inhibiting its dechlorination. The reactivity change could be explained with the properties of the aged RAC including surface area, Fe0 content, and Fe species. During the aging and oxidation, the RAC showed limited dissolution of Fe and Pd. Finally, implementation issues regarding application of RAC system to contaminated sites are discussed. 25 refs., 6 figs., 1 tab.

  14. Development of an aerosol microphysical module: Aerosol Two-dimensional bin module for foRmation and Aging Simulation (ATRAS)

    SciTech Connect (OSTI)

    Matsui, H.; Koike, Makoto; Kondo, Yutaka; Fast, Jerome D.; Takigawa, M.

    2014-09-30

    Number concentrations, size distributions, and mixing states of aerosols are essential parameters for accurate estimation of aerosol direct and indirect effects. In this study, we developed an aerosol module, designated Aerosol Two-dimensional bin module for foRmation and Aging Simulation (ATRAS), that can represent these parameters explicitly by considering new particle formation (NPF), black carbon (BC) aging, and secondary organic aerosol (SOA) processes. A two-dimensional bin representation is used for particles with dry diameters from 40 nm to 10 m to resolve both aerosol size (12 bins) and BC mixing state (10 bins) for a total of 120 bins. The particles with diameters from 1 to 40 nm are resolved using an additional 8 size bins to calculate NPF. The ATRAS module was implemented in the WRF-chem model and applied to examine the sensitivity of simulated mass, number, size distributions, and optical and radiative parameters of aerosols to NPF, BC aging and SOA processes over East Asia during the spring of 2009. BC absorption enhancement by coating materials was about 50% over East Asia during the spring, and the contribution of SOA processes to the absorption enhancement was estimated to be 10 20% over northern East Asia and 20 35% over southern East Asia. A clear north-south contrast was also found between the impacts of NPF and SOA processes on cloud condensation nuclei (CCN) concentrations: NPF increased CCN concentrations at higher supersaturations (smaller particles) over northern East Asia, whereas SOA increased CCN concentrations at lower supersaturations (larger particles) over southern East Asia. Application of ATRAS to East Asia also showed that the impact of each process on each optical and radiative parameter depended strongly on the process and the parameter in question. The module can be used in the future as a benchmark model to evaluate the accuracy of simpler aerosol models and examine interactions between NPF, BC aging, and SOA processes under different meteorological conditions and emissions.

  15. In Situ GISAXS investigation of low-temperature aging in oriented surfactant-mesostructured titania thin films

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Nagpure, Suraj; Das, Saikat; Garlapalli, Ravinder K.; Strzalka, Joseph; Rankin, Stephen E.

    2015-09-11

    In this study, the mechanism of forming orthogonally oriented hexagonal close packed (o-HCP) mesostructures during aging of surfactant-templated titania thin films is elucidated using in situ grazing incidence small-angle x-ray scattering (GISAXS) in a controlled-environment chamber. To promote orthogonal orientation, glass slides are modified with crosslinked Pluronic P123, to provide surfaces chemically neutral towards both blocks of mesophase template P123. At 4 °C and 80% RH, the o-HCP mesophase emerges in thin (~60 nm) films by a direct disorder-to-order transition, with no intermediate ordered mesophase. The Pluronic/titania o-HCP GISAXS intensity emerges only after ~10-12 minutes, much slower than previously reportedmore » for smallmolecule surfactants. The Avrami model applied to the data suggests 2D growth with nucleation at the start of the process with a half-life of 39.7 minutes for the aging time just after the induction period of 7 minutes followed by a period consistent with 1D growth kinetics. Surprisingly, films that are thicker (~250 nm) or cast on unmodified slides form o-HCP mesophase domains, but by a different mechanism (2D growth with continuous nucleation) with faster and less complete orthogonal alignment. Thus, the o-HCP mesophase is favored not only 2 by modifying the substrate, but also by aging at 4 °C, which is below the lower consolute temperature (LCST) of the poly(propylene oxide) block of P123. Consistent with this, in situ GISAXS shows that films aged at room temperature (above the LCST of the PPO block) have randomly oriented HCP mesostructure.« less

  16. Age-related changes in the plasticity and toughness of human cortical bone at multiple length-scales

    SciTech Connect (OSTI)

    Zimmermann, Elizabeth A.; Schaible, Eric; Bale, Hrishikesh; Barth, Holly D.; Tang, Simon Y.; Reichert, Peter; Busse, Bjoern; Alliston, Tamara; Ager III, Joel W.; Ritchie, Robert O.

    2011-08-10

    The structure of human cortical bone evolves over multiple length-scales from its basic constituents of collagen and hydroxyapatite at the nanoscale to osteonal structures at nearmillimeter dimensions, which all provide the basis for its mechanical properties. To resist fracture, bones toughness is derived intrinsically through plasticity (e.g., fibrillar sliding) at structural-scales typically below a micron and extrinsically (i.e., during crack growth) through mechanisms (e.g., crack deflection/bridging) generated at larger structural-scales. Biological factors such as aging lead to a markedly increased fracture risk, which is often associated with an age-related loss in bone mass (bone quantity). However, we find that age-related structural changes can significantly degrade the fracture resistance (bone quality) over multiple lengthscales. Using in situ small-/wide-angle x-ray scattering/diffraction to characterize sub-micron structural changes and synchrotron x-ray computed tomography and in situ fracture-toughness measurements in the scanning electron microscope to characterize effects at micron-scales, we show how these age-related structural changes at differing size-scales degrade both the intrinsic and extrinsic toughness of bone. Specifically, we attribute the loss in toughness to increased non-enzymatic collagen cross-linking which suppresses plasticity at nanoscale dimensions and to an increased osteonal density which limits the potency of crack-bridging mechanisms at micron-scales. The link between these processes is that the increased stiffness of the cross-linked collagen requires energy to be absorbed by plastic deformation at higher structural levels, which occurs by the process of microcracking.

  17. CHARACTERIZING ULTRAVIOLET AND INFRARED OBSERVATIONAL PROPERTIES FOR GALAXIES. I. INFLUENCES OF DUST ATTENUATION AND STELLAR POPULATION AGE

    SciTech Connect (OSTI)

    Mao Yewei; Kong Xu [Center for Astrophysics, University of Science and Technology of China, Hefei 230026 (China); Kennicutt, Robert C. Jr. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA (United Kingdom); Hao, Cai-Na [Tianjin Astrophysics Center, Tianjin Normal University, Tianjin 300387 (China); Zhou Xu, E-mail: owen81@mail.ustc.edu.cn, E-mail: xkong@ustc.edu.cn [National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

    2012-09-20

    The correlation between infrared-to-ultraviolet luminosity ratio and ultraviolet color (or ultraviolet spectral slope), i.e., the IRX-UV (or IRX-{beta}) relation, found in studies of starburst galaxies is a prevalent recipe for correcting extragalactic dust attenuation. Considerable dispersion in this relation discovered for normal galaxies, however, complicates its usability. In order to investigate the cause of the dispersion and to have a better understanding of the nature of the IRX-UV relation, in this paper, we select five nearby spiral galaxies, and perform spatially resolved studies on each of the galaxies, with a combination of ultraviolet and infrared imaging data. We measure all positions within each galaxy and divide the extracted regions into young and evolved stellar populations. By means of this approach, we attempt to discover separate effects of dust attenuation and stellar population age on the IRX-UV relation for individual galaxies. In this work, in addition to dust attenuation, stellar population age is interpreted to be another parameter in the IRX-UV function, and the diversity of star formation histories is suggested to disperse the age effects. At the same time, strong evidence shows the need for more parameters in the interpretation of observational data, such as variations in attenuation/extinction law. Fractional contributions of different components to the integrated luminosities of the galaxies suggest that the integrated measurements of these galaxies, which comprise different populations, would weaken the effect of the age parameter on IRX-UV diagrams. The dependence of the IRX-UV relation on luminosity and radial distance in galaxies presents weak trends, which offers an implication of selective effects. The two-dimensional maps of the UV color and the infrared-to-ultraviolet ratio are displayed and show a disparity in the spatial distributions between the two galaxy parameters, which offers a spatial interpretation of the scatter in the IRX-UV relation.

  18. Photometric investigation of the totally eclipsing contact binary V12 in the intermediate-age open cluster NGC 7789

    SciTech Connect (OSTI)

    Qian, S.-B.; Wang, J.-J.; Liu, L.; Zhou, X.; Essam, A.; Ali, G. B.; Haroon, A.-A.

    2015-02-01

    NGC 7789 is an intermediate-age open cluster with an age similar to the mean age of contact binary stars. V12 is a bright W UMa-type binary star with an orbital period of 0.3917 days. The first complete light curves of V12 in the V, R, and I bands are presented and analyzed with the WilsonDevinney (W-D) method. The results show that V12 is an intermediate-contact binary (f=43.0(2.2)%) with a mass ratio of 3.848, and it is a W-type contact binary where the less massive component is slightly hotter than the more massive one. The asymmetry of the light curves is explained by the presence of a dark spot on the more massive component. The derived orbital inclination (i=83{sub .}{sup ?}6) indicates that it is a totally eclipsing binary, which suggests that the determined parameters are reliable. The orbital period may show a long-term increase at a rate of P-dot =+2.48(0.17)10{sup ?6} days yr{sup ?1} that reveals a rapid mass transfer from the less massive component to the more massive one. However, more observations are needed to confirm this conclusion. The presence of an intermediate-contact binary in an intermediate-age open cluster may suggest that some contact binaries have a very short pre-contact timescale. The presence of a third body and/or stellar collision may help to shorten the pre-contact evolution.

  19. State of the Art Assessment of NDE Techniques for Aging Cable Management in Nuclear Power Plants FY2015

    SciTech Connect (OSTI)

    Glass, Samuel W.; Fifield, Leonard S.; Dib, Gerges; Tedeschi, Jonathan R.; Jones, Anthony M.; Hartman, Trenton S.

    2015-09-08

    This milestone report presents an update on the state-of-the-art review and research being conducted to identify key indicators of in-containment cable aging at nuclear power plants (NPPs), and devise in-situ measurement techniques that are sensitive to these key indicators. The motivation for this study stems from the need to address open questions related to nondestructive evaluation (NDE) of aging cables for degradation detection and estimation of condition-based remaining service life. These questions arise within the context of a second round of license extension for NPPs that would extend the operating license to 60 and 80 years. Within the introduction, a review of recently published U.S. and international research and guidance for cable aging management programs including NDE technologies is provided. As with any “state-of-the-art” report, the observations are deemed accurate as of the publication date but cannot anticipate evolution of the technology. Moreover, readers are advised that research and development of cable NDE technology is an ongoing issue of global concern.

  20. Sr-isotopic composition of marbles from the Puerto Galera area (Mindoro, Philippines): additional evidence for a Paleozoic age of a metamorphic complex in the Philippine island arc

    SciTech Connect (OSTI)

    Knittel, U.; Daniels, U.

    1987-02-01

    The Sr-isotopic composition of marbles from the Puerto Galera area (Mindoro, Philippines) is compatible with either a Tertiary or a Paleozoic age. The former is considered as unlikely because nonmetamorphic sediments of that age overlie the metamorphic complex. This implies that the metamorphic complex does not represent the basement of the Philippine arc but is an accreted terrane.

  1. FORM AND AGING OF PLUTONIUM IN SAVANNAH RIVER SITE WASTE TANK 18

    SciTech Connect (OSTI)

    Hobbs, D.

    2012-02-24

    This report provides a summary of the effects of aging on and the expected forms of plutonium in Tank 18 waste residues. The findings are based on available information on the operational history of Tank 18, reported analytical results for samples taken from Tank 18, and the available scientific literature for plutonium under alkaline conditions. These findings should apply in general to residues in other waste tanks. However, the operational history of other waste tanks should be evaluated for specific conditions and unique operations (e.g., acid cleaning with oxalic acid) that could alter the form of plutonium in heel residues. Based on the operational history of other tanks, characterization of samples from the heel residues in those tanks would be appropriate to confirm the form of plutonium. During the operational period and continuing with the residual heel removal periods, Pu(IV) is the dominant oxidation state of the plutonium. Small fractions of Pu(V) and Pu(VI) could be present as the result of the presence of water and the result of reactions with oxygen in air and products from the radiolysis of water. However, the presence of Pu(V) would be transitory as it is not stable at the dilute alkaline conditions that currently exists in Tank 18. Most of the plutonium that enters Savannah River Site (SRS) high-level waste (HLW) tanks is freshly precipitated as amorphous plutonium hydroxide, Pu(OH){sub 4(am)} or hydrous plutonium oxide, PuO{sub 2(am,hyd)} and coprecipitated within a mixture of hydrous metal oxide phases containing metals such as iron, aluminum, manganese and uranium. The coprecipitated plutonium would include Pu{sup 4+} that has been substituted for other metal ions in crystal lattice sites, Pu{sup 4+} occluded within hydrous metal oxide particles and Pu{sup 4+} adsorbed onto the surface of hydrous metal oxide particles. The adsorbed plutonium could include both inner sphere coordination and outer sphere coordination of the plutonium. PuO{sub 2(am,hyd)} is also likely to be present in deposits and scales that have formed on the steel surfaces of the tank. Over the operational period and after closure of Tank 18, Ostwald ripening has and will continue to transform PuO{sub 2(am,hyd)} to a more crystalline form of plutonium dioxide, PuO{sub 2(c)}. After bulk waste removal and heel retrieval operations, the free hydroxide concentration decreased and the carbonate concentration in the free liquid and solids increased. Consequently, a portion of the PuO{sub 2(am,hyd)} has likely been converted to a hydroxy-carbonate complex such as Pu(OH){sub 2}(CO{sub 3}){sub (s)}. or PuO(CO{sub 3}) {center_dot} xH{sub 2}O{sub (am)}. Like PuO{sub 2(am,hyd)}, Ostwald ripening of Pu(OH){sub 2}(CO{sub 3}){sub (s)} or PuO(CO{sub 3}) {center_dot} xH{sub 2}O{sub (am)} would be expected to occur to produce a more crystalline form of the plutonium carbonate complex. Due to the high alkalinity and low carbonate concentration in the grout formulation, it is expected that upon interaction with the grout, the plutonium carbonate complexes will transform back into plutonium hydroxide. Although crystalline plutonium dioxide is the more stable thermodynamic state of Pu(IV), the low temperature and high water content of the waste during the operating and heel removal periods in Tank 18 have limited the transformation of the plutonium into crystalline plutonium dioxide. During the tank closure period of thousands of years, transformation of the plutonium into a more crystalline plutonium dioxide form would be expected. However, the continuing presence of water, reaction with water radiolysis products, and low temperatures will limit the transformation, and will likely maintain an amorphous Pu(OH){sub 4} or PuO{sub 2(am,hyd)} form on the surface of any crystalline plutonium dioxide produced after tank closure. X-ray Absorption Spectroscopic (XAS) measurements of Tank 18 residues are recommended to confirm coordination environments of the plutonium. If the presence of PuO(CO{sub 3}){sub (am,hyd)} is confirmed by XAS, it is recommended that e

  2. A Proof of Concept: Grizzly, the LWRS Program Materials Aging and Degradation Pathway Main Simulation Tool

    SciTech Connect (OSTI)

    Ben Spencer; Jeremey Busby; Richard Martineau; Brian Wirth

    2012-10-01

    Nuclear power currently provides a significant fraction of the United States’ non-carbon emitting power generation. In future years, nuclear power must continue to generate a significant portion of the nation’s electricity to meet the growing electricity demand, clean energy goals, and ensure energy independence. New reactors will be an essential part of the expansion of nuclear power. However, given limits on new builds imposed by economics and industrial capacity, the extended service of the existing fleet will also be required.

  3. Test series 1: seismic-fragility tests of naturally-aged Class 1E Gould NCX-2250 battery cells

    SciTech Connect (OSTI)

    Bonzon, L. L.; Hente, D. B.; Kukreti, B. M.; Schendel, J. S.; Tulk, J. D.; Janis, W. J.; Black, D A; Paulsen, G. D.; Aucoin, B. D.

    1984-09-01

    The seismic-fragility response of naturally-aged, nuclear station, safety-related batteries is of interest for two reasons: (1) to determine actual failure modes and thresholds; and (2) to determine the validity of using the electrical capacity of individual cells as an indicator of the end-of-life of a battery, given a seismic event. This report covers the first test series of an extensive program using 12-year old, lead-calcium, Gould NCX-2250 cells, from the James A. Fitzpatrick Nuclear Power Station operated by the New York Power Authority. Seismic tests with three cell configurations were performed using a triaxial shake table: single-cell tests, rigidly mounted; multi-cell (three) tests, mounted in a typical battery rack; and single-cell tests specifically aimed towards examining propagation of pre-existing case cracks. In general the test philosophy was to monitor the electrical properties including discharge capacity of cells through a graduated series of g-level step increases until either the shake-table limits were reached or until electrical failure of the cells occurred. Of nine electrically active cells, six failed during seismic testing over a range of imposed g-level loads in excess of a 1-g ZPA. Post-test examination revealed a common failure mode, the cracking at the abnormally brittle, positive lead bus-bar/post interface; further examination showed that the failure zone was extremely coarse grained and extensively corroded. Presently accepted accelerated-aging methods for qualifying batteries, per IEEE Std. 535-1979, are based on plate growth, but these naturally-aged 12-year old cells showed no significant plate growth.

  4. Study of Inhibition, Reactivation and Aging Processes of Pesticides Using Graphene Nanosheets/Gold Nanoparticles-Based Acetylcholinesterase Biosensor

    SciTech Connect (OSTI)

    Zhang, Lin; Long, Linjuan; Zhang, Weiying; Du, Dan; Lin, Yuehe

    2012-09-10

    Organophosphate (OP) and carbamate pesticides exert their toxicity via attacking the hydroxyl moiety of serine in the 'active site' of acetylcholinesterase (AChE). In this paper we developed a stable AChE biosensor based on self-assembling AChE to graphene nanosheet (GN)-gold nanoparticles (AuNPs) nanocomposite electrode for investigation of inhibition, reactivation and aging processes of different pesticides. It is confirmed that pesticides can inhibit AChE in a short time. OPs poisoning is treatable with oximes while carbarmates exposure is insensitive to oximes. The proposed electrochemical approach thus provides a new simple tool for comparison of pesticide sensitivity and guide of therapeutic intervention.

  5. New Technologies for Repairing Aging Cables in Nuclear Power Plants: M3LW-14OR0404015 Cable Rejuvenation Report

    SciTech Connect (OSTI)

    Simmons, Kevin L.; Fifield, Leonard S.; Westman, Matthew P.; Roberts, John A.

    2014-09-08

    The goal of this project is to conceptually demonstrate techniques to repair cables that have degraded through subjection to long-term thermal and radiation exposure in nuclear power plants. In fiscal year 2014 (FY14) we focused on commercially available ethylene-propylene rubber (EPR) as the relevant test material, isolated a high surface area form of the EPR material to facilitate chemical treatment screening and charaterization, and measured chemical changes in the material due to aging and treatment using Fourier Transfrom Infrared (FTIR) spectroscopy.

  6. Aging Study Of EPDM O-Ring Material For The H1616 Shipping Package - Three Year Status

    SciTech Connect (OSTI)

    Stefek, T.; Daugherty, W.; Skidmore, E.

    2015-11-05

    This is a 3-year status report for tasks carried out per Task Technical Plan SRNL-STI-2011-00506. A series of tasks/experiments were performed at the Savannah River National Laboratory (SRNL) to monitor the aging performance of ethylene propylene diene monomer (EPDM) O-rings used in the H1616 shipping package. The test data provide a technical basis to extend the annual maintenance of the H1616 shipping package to three years and to predict the life of the EPDM O-rings at the bounding service conditions.

  7. Chemical aging of single and multicomponent biomass burning aerosol surrogate-particles by OH: implications for cloud condensation nucleus activity

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Slade, J. H.; Thalman, R.; Wang, J.; Knopf, D. A.

    2015-03-06

    Multiphase OH and O3 oxidation reactions with atmospheric organic aerosol (OA) can influence particle physicochemical properties including composition, morphology, and lifetime. Chemical aging of initially insoluble or low soluble single-component OA by OH and O3 can increase their water-solubility and hygroscopicity, making them more active as cloud condensation nuclei (CCN) and susceptible to wet deposition. However, an outstanding problem is whether the effects of chemical aging on their CCN activity are preserved when mixed with other organic or inorganic compounds exhibiting greater water-solubility. In this work, the CCN activity of laboratory-generated biomass burning aerosol (BBA) surrogate-particles exposed to OH andmore » O3 is evaluated by determining the hygroscopicity parameter, κ, as a function of particle type, mixing state, and OH/O3 exposure applying a CCN counter (CCNc) coupled to an aerosol flow reactor (AFR). Levoglucosan (LEV), 4-methyl-5-nitrocatechol (MNC), and potassium sulfate (KS) serve as representative BBA compounds that exhibit different hygroscopicity, water solubility, chemical functionalities, and reactivity with OH radicals, and thus exemplify the complexity of mixed inorganic/organic aerosol in the atmosphere. The CCN activities of all of the particles were unaffected by O3 exposure. Following exposure to OH, κ of MNC was enhanced by an order of magnitude, from 0.009 to ~0.1, indicating that chemically-aged MNC particles are better CCN and more prone to wet deposition than pure MNC particles. No significant enhancement in κ was observed for pure LEV particles following OH exposure. κ of the internally-mixed particles was not affected by OH oxidation. Furthermore, the CCN activity of OH exposed MNC-coated KS particles is similar to the OH unexposed atomized 1 : 1 by mass MNC : KS binary-component particles. Our results strongly suggest that when OA is dominated by water-soluble organic carbon (WSOC) or inorganic ions, chemical aging has no significant impact on OA hygroscopicity. The organic compounds exhibiting low solubility behave as if they are infinitely soluble when mixed with a sufficient amount of water-soluble compounds. At and beyond this point, the particles' CCN activity is governed entirely by the water-soluble fraction and not influenced by the oxidized organic fraction. Our results have important implications for heterogeneous oxidation and its impact on cloud formation given that atmospheric aerosol is a complex mixture of organic and inorganic compounds exhibiting a wide-range of solubilities.« less

  8. Chemical aging of single and multicomponent biomass burning aerosol surrogate particles by OH: implications for cloud condensation nucleus activity

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Slade, J. H.; Thalman, R.; Wang, J.; Knopf, D. A.

    2015-09-14

    Multiphase OH and O3 oxidation reactions with atmospheric organic aerosol (OA) can influence particle physicochemical properties including composition, morphology, and lifetime. Chemical aging of initially insoluble or low-soluble single-component OA by OH and O3 can increase their water solubility and hygroscopicity, making them more active as cloud condensation nuclei (CCN) and susceptible to wet deposition. However, an outstanding problem is whether the effects of chemical aging on their CCN activity are preserved when mixed with other organic or inorganic compounds exhibiting greater water solubility. In this work, the CCN activity of laboratory-generated biomass burning aerosol (BBA) surrogate particles exposed tomore » OH and O3 is evaluated by determining the hygroscopicity parameter, κ, as a function of particle type, mixing state, and OH and O3 exposure applying a CCN counter (CCNc) coupled to an aerosol flow reactor (AFR). Levoglucosan (LEV), 4-methyl-5-nitrocatechol (MNC), and potassium sulfate (KS) serve as representative BBA compounds that exhibit different hygroscopicity, water solubility, chemical functionalities, and reactivity with OH radicals, and thus exemplify the complexity of mixed inorganic/organic aerosol in the atmosphere. The CCN activities of all of the particles were unaffected by O3 exposure. Following exposure to OH, κ of MNC was enhanced by an order of magnitude, from 0.009 to ~ 0.1, indicating that chemically aged MNC particles are better CCN and more prone to wet deposition than pure MNC particles. No significant enhancement in κ was observed for pure LEV particles following OH exposure. κ of the internally mixed particles was not affected by OH oxidation. Furthermore, the CCN activity of OH-exposed MNC-coated KS particles is similar to the OH unexposed atomized 1 : 1 by mass MNC : KS binary-component particles. Our results strongly suggest that when OA is dominated by water-soluble organic carbon (WSOC) or inorganic ions, chemical aging has no significant impact on OA hygroscopicity. The organic compounds exhibiting low solubility behave as if they are infinitely soluble when mixed with a sufficient number of water-soluble compounds. At and beyond this point, the particles' CCN activity is governed entirely by the water-soluble fraction and is not influenced by the oxidized organic fraction. Our results have important implications for heterogeneous oxidation and its impact on cloud formation given that atmospheric aerosol is a complex mixture of organic and inorganic compounds exhibiting a wide range of solubilities.« less

  9. THE RELATIONSHIP BETWEEN {nu}{sub max} AND AGE t FROM ZAMS TO RGB-TIP FOR LOW-MASS STARS

    SciTech Connect (OSTI)

    Tang, Y. K.; Gai, N. E-mail: ning.gai@hotmail.com

    2013-07-10

    Stellar age is an important quantity in astrophysics, which is useful for many fields both in the universe and galaxies. It cannot be determined by direct measurements, but can only be estimated or inferred. We attempt to find a useful indicator of stellar age, which is accurate from the zero-age main sequence to the tip of red giant branch for low-mass stars. Using the Yale Rotation and Evolution Code (YREC), a grid of stellar models has been constructed. Meanwhile, the frequency of maximum oscillations' power {nu}{sub max} and the large frequency separation {Delta}{nu} are calculated using the scaling relations. For the stars, the masses of which are from 0.8 M{sub Sun} to 2.8 M{sub Sun }, we can obtain the {nu}{sub max} and stellar age by combing the scaling relations with the four sets of grid models (YREC, Dotter et al., Marigo et al., and YY isochrones). We find that {nu}{sub max} is tightly correlated and decreases monotonically with the age of the star from the main sequence to the red giant evolutionary stages. Moreover, we find that the line shapes of the curves in the Age versus {nu}{sub max} diagram, which is plotted by the four sets of grid models, are consistent for red giants with masses from 1.1 M{sub Sun} to 2.8 M{sub Sun }. For red giants, the differences of correlation coefficients between Age and {nu}{sub max} for different grid models are minor and can be ignored. Interestingly, we find two peaks that correspond to the subgiants and bump of red giants in the Age versus {nu}{sub max} diagram. By general linear least-squares, we make the polynomial fitting and deduce the relationship between log(Age) and log({nu}{sub max}) in red giants' evolutionary state.

  10. Aging of niobium and tantalum tritides: Evolution of hardness in comparison with other properties

    SciTech Connect (OSTI)

    Schober, T.; Dieker, C.; Trinkaus, H.

    1989-01-01

    Vickers hardness measurements on niobium and tantalum tritides of initial composition NbT/sub 0.0225/ and TaT/sub 0.097/, respectively, performed over the first 20 months after T charging, are reported and interpreted. For both tritides, the hardness increases monotonically, but in a decelerating rate, with the /sup 3/ He concentration built up upon T transmutation. At given /sup 3/ He concentration, the increase per unit /sup 3/ He concentration is stronger for Nb than for Ta. To interpret the observed hardness evolution, existing hardening theories are adjusted to the present microstructural situations. It is concluded that the microstructure developing on /sup 3/ He precipitation is more disperse in the Nb tritide than in the Ta tritide. These findings are supported by conclusions drawn previously from swelling, acoustic emission, and x-ray diffraction measurements of these materials.

  11. Genome-wide Analysis of Drosophila Circular RNAs Reveals Their Structural and Sequence Properties and Age-Dependent Neural Accumulation

    SciTech Connect (OSTI)

    Westholm, Jakub O.; Miura, Pedro; Olson, Sara; Shenker, Sol; Joseph, Brian; Sanfilippo, Piero; Celniker, Susan E.; Graveley, Brenton R.; Lai, Eric C.

    2014-11-26

    Circularization was recently recognized to broadly expand transcriptome complexity. Here, we exploit massive Drosophila total RNA-sequencing data, >5 billion paired-end reads from >100 libraries covering diverse developmental stages, tissues, and cultured cells, to rigorously annotate >2,500 fruit fly circular RNAs. These mostly derive from back-splicing of protein-coding genes and lack poly(A) tails, and the circularization of hundreds of genes is conserved across multiple Drosophila species. We elucidate structural and sequence properties of Drosophila circular RNAs, which exhibit commonalities and distinctions from mammalian circles. Notably, Drosophila circular RNAs harbor >1,000 well-conserved canonical miRNA seed matches, especially within coding regions, and coding conserved miRNA sites reside preferentially within circularized exons. Finally, we analyze the developmental and tissue specificity of circular RNAs and note their preferred derivation from neural genes and enhanced accumulation in neural tissues. Interestingly, circular isoforms increase substantially relative to linear isoforms during CNS aging and constitute an aging biomarker.

  12. Aging of secondary organic aerosol from small aromatic VOCs. Changes in chemical composition, mass yield, volatility and hygroscopicity

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hildebrandt Ruiz, L.; Paciga, A. L.; Cerully, K.; Nenes, A.; Donahue, N. M.; Pandis, S. N.

    2014-12-12

    Secondary organic aerosol (SOA) is transformed after its initial formation, but this chemical aging of SOA is poorly understood. Experiments were conducted in the Carnegie Mellon environmental chamber to form and transform SOA from the photo-oxidation of toluene and other small aromatic volatile organic compounds (VOCs) in the presence of NOx. The effects of chemical aging on organic aerosol (OA) composition, mass yield, volatility and hygroscopicity were explored. Higher exposure to the hydroxyl radical resulted in different OA composition, average carbon oxidation state OSC) and mass yield. The OA oxidation state generally increased during photo-oxidation, and the final OA OSmore » C ranged from -0.29 to 0.45 in the performed experiments. The volatility of OA formed in these different experiments varied by as much as a factor of 30, demonstrating that the OA formed under different oxidizing conditions can have significantly different saturation concentration. There was no clear correlation between hygroscopicity and oxidation state for this relatively hygroscopic SOA.« less

  13. Genome-wide Analysis of Drosophila Circular RNAs Reveals Their Structural and Sequence Properties and Age-Dependent Neural Accumulation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Westholm, Jakub O.; Miura, Pedro; Olson, Sara; Shenker, Sol; Joseph, Brian; Sanfilippo, Piero; Celniker, Susan E.; Graveley, Brenton R.; Lai, Eric C.

    2014-11-26

    Circularization was recently recognized to broadly expand transcriptome complexity. Here, we exploit massive Drosophila total RNA-sequencing data, >5 billion paired-end reads from >100 libraries covering diverse developmental stages, tissues, and cultured cells, to rigorously annotate >2,500 fruit fly circular RNAs. These mostly derive from back-splicing of protein-coding genes and lack poly(A) tails, and the circularization of hundreds of genes is conserved across multiple Drosophila species. We elucidate structural and sequence properties of Drosophila circular RNAs, which exhibit commonalities and distinctions from mammalian circles. Notably, Drosophila circular RNAs harbor >1,000 well-conserved canonical miRNA seed matches, especially within coding regions, and codingmoreconserved miRNA sites reside preferentially within circularized exons. Finally, we analyze the developmental and tissue specificity of circular RNAs and note their preferred derivation from neural genes and enhanced accumulation in neural tissues. Interestingly, circular isoforms increase substantially relative to linear isoforms during CNS aging and constitute an aging biomarker.less

  14. A VLT/FLAMES STUDY OF THE PECULIAR INTERMEDIATE-AGE LARGE MAGELLANIC CLOUD STAR CLUSTER NGC 1846. I. KINEMATICS

    SciTech Connect (OSTI)

    Mackey, A. D.; Da Costa, G. S.; Yong, D.; Ferguson, A. M. N.

    2013-01-01

    In this paper we present high-resolution VLT/FLAMES observations of red giant stars in the massive intermediate-age Large Magellanic Cloud star cluster NGC 1846, which, on the basis of its extended main-sequence turnoff (EMSTO), possesses an internal age spread of Almost-Equal-To 300 Myr. We describe in detail our target selection and data reduction procedures, and construct a sample of 21 stars possessing radial velocities indicating their membership of NGC 1846 at high confidence. We consider high-resolution spectra of the planetary nebula Mo-17, and conclude that this object is also a member of the cluster. Our measured radial velocities allow us to conduct a detailed investigation of the internal kinematics of NGC 1846, the first time this has been done for an EMSTO system. The key result of this work is that the cluster exhibits a significant degree of systemic rotation, of a magnitude comparable to the mean velocity dispersion. Using an extensive suite of Monte Carlo models we demonstrate that, despite our relatively small sample size and the substantial fraction of unresolved binary stars in the cluster, the rotation signal we detect is very likely to be genuine. Our observations are in qualitative agreement with the predictions of simulations modeling the formation of multiple populations of stars in globular clusters, where a dynamically cold, rapidly rotating second generation is a common feature. NGC 1846 is less than one relaxation time old, so any dynamical signatures encoded during its formation ought to remain present.

  15. Constraining the age of the NGC 4565 H I disk WARP: Determining the origin of gas WARPS

    SciTech Connect (OSTI)

    Radburn-Smith, David J.; Dalcanton, Julianne J.; Stilp, Adrienne M.; De Jong, Roelof S.; Streich, David; Bell, Eric F.; Monachesi, Antonela; Dolphin, Andrew E.; Holwerda, Benne W.; Bailin, Jeremy

    2014-01-01

    We have mapped the distribution of young and old stars in the gaseous H I warp of NGC 4565. We find a clear correlation of young stars (<600 Myr) with the warp but no coincident old stars (>1 Gyr), which places an upper limit on the age of the structure. The formation rate of the young stars, which increased ?300 Myr ago relative to the surrounding regions, is (6.3{sub ?1.5}{sup +2.5})10{sup ?5} M {sub ?} yr{sup 1} kpc{sup 2}. This implies a ?60 20 Gyr depletion time of the H I warp, similar to the timescales calculated for the outer H I disks of nearby spiral galaxies. While some stars associated with the warp fall into the asymptotic giant branch (AGB) region of the color-magnitude diagram, where stars could be as old as 1 Gyr, further investigation suggests that they may be interlopers rather than real AGB stars. We discuss the implications of these age constraints for the formation of H I warps and the gas fueling of disk galaxies.

  16. Living in the Nuclear Age: Families and the threat of nuclear war

    SciTech Connect (OSTI)

    Demorest, D.M.

    1991-01-01

    The main interest of this research was to add to the body of knowledge about the possible psychological impact of the nuclear threat on the family unit. Data were utilized from the Family Interaction, Stress and Nuclear War study conducted by Jules Riskin, M.D. and Victoria Dickerson, Ph.D. at the Mental Research Institute in Palo Alto, California. The sample consisted of ten families who were recruited for this study. In order to examine family-interaction variables and the impact of the threat of nuclear war, a standardized semi-structured family interview was conducted. Topics ranged from ordinary activities to external, non-nuclear stresses such as landslides or hurricanes, to the topic of nuclear war. A distinction is drawn between a family's level of nuclear concern while they discuss nuclear issues and a family's level of nuclear concern when viewed in the context of their overall pattern of family communication. In terms of family coping, family nuclear concern was found to be significantly related to two family-coping strategies. Families who utilized the coping strategies of seeking spiritual support and mobilizing the family to acquire and accept help were significantly less concerned about the threat of nuclear war.

  17. Final Report, The Influence of Organic-Aerosol Emissions and Aging on Regional and Global Aerosol Size Distributions and the CCN Number Budget

    SciTech Connect (OSTI)

    Donahue, Neil M.

    2015-12-23

    We conducted laboratory experiments and analyzed data on aging of organic aerosol and analysis of field data on volatility and CCN activity. With supplemental ASR funding we participated in the FLAME-IV campaign in Missoula MT in the Fall of 2012, deploying a two-chamber photochemical aging system to enable experimental exploration of photochemical aging of biomass burning emissions. Results from that campaign will lead to numerous publications, including demonstration of photochemical production of Brown Carbon (BrC) from secondary organic aerosol associated with biomass burning emissions as well as extensive characterization of the effect of photochemical aging on the overall concentrations of biomass burning organic aerosol. Excluding publications arising from the FLAME-IV campaign, project research resulted in 8 papers: [11, 5, 3, 10, 12, 4, 8, 7], including on in Nature Geoscience addressing the role of organic compounds in nanoparticle growth [11

  18. Molecular transformations of phenolic SOA during photochemical aging in the aqueous phase: competition among oligomerization, functionalization, and fragmentation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yu, L.; Smith, J.; Laskin, A.; George, K. M.; Anastasio, C.; Laskin, J.; Dillner, A. M.; Zhang, Q.

    2015-10-30

    Organic aerosol is formed and transformed in atmospheric aqueous phases (e.g., cloud and fog droplets and deliquesced airborne particles containing small amounts of water) through a multitude of chemical reactions. Understanding these reactions is important for a predictive understanding of atmospheric aging of aerosols and their impacts on climate, air quality, and human health. In this study, we investigate the chemical evolution of aqueous secondary organic aerosol (aqSOA) formed during reactions of phenolic compounds with two oxidants the triplet excited state of an aromatic carbonyl (3C*) and hydroxyl radical (OH). Changes in the molecular composition of aqSOA as amorefunction of aging time are characterized using an offline nanospray desorption electrospray ionization mass spectrometer (nano-DESI MS) whereas the real-time evolution of SOA mass, elemental ratios, and average carbon oxidation state (OSC) are monitored using an online aerosol mass spectrometer (AMS). Our results indicate that oligomerization is an important aqueous reaction pathway for phenols, especially during the initial stage of photooxidation equivalent to ? 2 h irradiation under midday, winter solstice sunlight in northern California. At later reaction times functionalization (i.e., adding polar oxygenated functional groups to the molecule) and fragmentation (i.e., breaking of covalent bonds) become more important processes, forming a large variety of functionalized aromatic and open-ring products with higher OSC values. Fragmentation reactions eventually dominate the photochemical evolution of phenolic aqSOA, forming a large number of highly oxygenated open-ring molecules with carbon numbers (nC) below 6. The average nC of phenolic aqSOA decreases while average OSC increases over the course of photochemical aging. In addition, the saturation vapor pressures C*) of dozens of the most abundant phenolic aqSOA molecules are estimated. A wide range of C* values is observed, varying from -20 ?g m-3 for functionalized phenolic oligomers to > 10 ?g m-3 for small open-ring species. The detection of abundant extremely low volatile organic compounds (ELVOC) indicates that aqueous reactions of phenolic compounds are likely an important source of ELVOC in the atmosphere.less

  19. Star-cluster mass and age distributions of two fields in M83 based on HST/WFC3 observations

    SciTech Connect (OSTI)

    Chandar, Rupali; Whitmore, Bradley C.; Calzetti, Daniela; O'Connell, Robert

    2014-05-20

    We study star clusters in two fields in the nearby spiral galaxy M83 using broadband and narrowband optical imaging taken with the Wide Field Camera 3 onboard the Hubble Space Telescope. We present results on the basis of several different catalogs of star clusters in inner and outer fields, and we conclude that different methods of selection do not strongly affect the results, particularly for clusters older than ?10 Myr. The age distributions can be described by a power law, dN/d???{sup ?}, with ? ? 0.84 0.12 in the inner field, and ? ? 0.48 0.12 in the outer field for ? ? 10 Myr. We bracket the difference, ??, between the two fields to be in the 0.18 to 0.36 range, based on estimates of the relative star-formation histories. The mass functions can also be described by a power law, dN/dM?M {sup ?}, with ? ? 1.98 0.14 and ? ? 2.34 0.26 in the inner and outer fields, respectively. We conclude that the shapes of the mass and age distributions of the clusters in the two fields are similar, as predicted by the quasi-universal model. Any differences between the two fields are at the ?2?-3? (?1?-2?) level for the age (mass) distributions. Therefore, any dependence of these distributions on the local environment is probably weak. We compare the shapes of the distributions with those predicted by two popular cluster disruption models. We find that both show evidence that the clusters are disrupted at a rate that is approximately independent of their mass. We compare the shapes of the distributions with those predicted by two popular cluster disruption models, and find that both show evidence that the clusters are disrupted at a rate that is approximately independent of their mass, and that observational results do not support the earlier disruption of lower-mass clusters relative to their higher-mass counterparts.

  20. Seismic fragility testing of naturally-aged, safety-related, class 1E battery cells. [PWR; BWR

    SciTech Connect (OSTI)

    Bonzon, L.L.; Hente, D.B.; Kukreti, B.M.; Schendel, J.S.; Black, D.A.; Paulsen, G.D.; Tulk, J.D.; Janis, W.J.; Aucoin, B.D.

    1984-01-01

    The concern over seismic susceptibility of naturally-aged lead-acid batteries used for safety-related emergency power in nuclear power stations was brought about by battery problems that periodically had been reported in Licensee Event Reports (LERs). The Turkey Point Station had reported cracked and buckled plates in several cells in October 1974 (LER 75-5). The Fitzpatrick Station had reported cracked battery cell cases in October 1977 (LER 77-55) and again in September 1979 (LER 79-59). The Browns Ferry Station had reported a cracked cell leaking a small quantity of electrolyte in July 1981 (LER 81-42). The Indian Point Station had reported cracked and leaking cells in both February (LER 82-7) and April 1982 (LER 82-16); both of these LERs indicated the cracked cells were due to expansion (i.e., growth) of the positive plates.

  1. Constraining dark energy models using the lookback time to galaxy clusters and the age of the universe

    SciTech Connect (OSTI)

    Capozziello, S.; Cardone, V.F.; Funaro, M.; Andreon, S.

    2004-12-15

    An impressive amount of different astrophysical data converges towards the picture of a spatially flat Universe undergoing today a phase of accelerated expansion. The nature of the dark energy dominating the energy content of the Universe is still unknown, and a lot of different scenarios are viable candidates to explain cosmic acceleration. Most of the methods employed to test these cosmological models are essentially based on distance measurements to a particular class of objects. A different method, based on the lookback time to galaxy clusters and the age of the Universe, is used here. In particular, we constrain the characterizing parameters of three classes of dark energy cosmological models to see whether they are in agreement with this kind of data, based on time measurements rather than distance observations.

  2. Assessment of landfill reclamation and the effects of age on the combustion of recovered municipal solid waste

    SciTech Connect (OSTI)

    Forster, G.A.

    1995-01-01

    This report summarized the Lancaster county Solid Waste Management Authorities`s (LCSWMA)landfill reclamation activities, ongoing since 1991. All aspects have been analyzed from the manpower and equipment requirements at the landfill to the operational impacts felt at the LCSWMA Resource Recovery Facility (RRF) where the material is delivered for processing. Characteristics of the reclaimed refuse and soil recovered from trommeling operations are discussed as are results of air monitoring performed at the landfill excavation site and the RRF. The report also discusses the energy value of the reclaimed material and compares this value with those obtained for significantly older reclaimed waste streams. The effects of waste age on the air emissions and ash residue quality at the RRF are also provided. The report concludes by summarizing the project benefits and provides recommendations for other landfill reclamation operations and areas requiring further research.

  3. Initial precipitation and hardening mechanism during non-isothermal aging in an Al–Mg–Si–Cu 6005A alloy

    SciTech Connect (OSTI)

    Yang, Wenchao; Ji, Shouxun; Huang, Lanping; Sheng, Xiaofei; Li, Zhou; Wang, Mingpu

    2014-08-15

    The characterization of precipitation and hardening mechanism during non-isothermal aging had been investigated using high resolution transmission electron microscopy for an Al–Mg–Si–Cu 6005A alloy. It was proposed that the needle-shaped β″ precipitates with a three-dimension coherency strain-field and an increased number density in the Al matrix provided the maximum strengthening effect for the Al–Mg–Si–Cu 6005A alloy. Simultaneously, it was also found that the formation and evolution of clusters in the early precipitation were associated with the vacancy binding energy, during which Si atoms played an important role in controlling the numbers density of Mg/Si co-clusters, and the excess Si atoms provided the increased number of nucleation sites for the subsequent precipitates to strengthen and improve the precipitation rate. Finally, based on the experimental observation and theoretical analysis, the precipitation sequence during the early precipitation in the Al–Mg–Si–Cu 6005A alloy was proposed as: supersaturated solid solution → Si-vacancy pairs, Mg-vacancy pairs and Mg clusters → Si clusters, and dissolution of Mg clusters → Mg atoms diffusion into the existing Si clusters → Mg/Si co-clusters → GP zone. - Highlights: • β″ precipitates provide the maximum strengthening effect for the 6005A alloy. • Si atoms play an important role in controlling the numbers of Mg/Si co-clusters. • The early aging sequence is deduced based on the solute-vacancy binding energy.

  4. Light Water Reactor Sustainability (LWRS) Program – Non-Destructive Evaluation (NDE) R&D Roadmap for Determining Remaining Useful Life of Aging Cables in Nuclear Power Plants

    SciTech Connect (OSTI)

    Simmons, Kevin L.; Ramuhalli, Pradeep; Brenchley, David L.; Coble, Jamie B.; Hashemian, Hash; Konnik, Robert; Ray, Sheila

    2012-09-14

    The purpose of the non-destructive evaluation (NDE) R&D Roadmap for Cables is to support the Materials Aging and Degradation (MAaD) R&D pathway. The focus of the workshop was to identify the technical gaps in detecting aging cables and predicting their remaining life expectancy. The workshop was held in Knoxville, Tennessee, on July 30, 2012, at Analysis and Measurement Services Corporation (AMS) headquarters. The workshop was attended by 30 experts in materials, electrical engineering, U.S. Nuclear Regulatory Commission (NRC), U.S. Department of Energy (DOE) National Laboratories (Oak Ridge National Laboratory, Pacific Northwest National Laboratory, Argonne National Laboratory, and Idaho National Engineering Laboratory), NDE instrumentation development, universities, commercial NDE services and cable manufacturers, and Electric Power Research Institute (EPRI). The motivation for the R&D roadmap comes from the need to address the aging management of in-containment cables at nuclear power plants (NPPs).

  5. A Novel Method for Predicting Late Genitourinary Toxicity After Prostate Radiation Therapy and the Need for Age-Based Risk-Adapted Dose Constraints

    SciTech Connect (OSTI)

    Ahmed, Awad A.; Egleston, Brian; Alcantara, Pino; Li, Linna; Pollack, Alan; Horwitz, Eric M.; Buyyounouski, Mark K.

    2013-07-15

    Background: There are no well-established normal tissue sparing dosevolume histogram (DVH) criteria that limit the risk of urinary toxicity from prostate radiation therapy (RT). The aim of this study was to determine which criteria predict late toxicity among various DVH parameters when contouring the entire solid bladder and its contents versus the bladder wall. The area under the histogram curve (AUHC) was also analyzed. Methods and Materials: From 1993 to 2000, 503 men with prostate cancer received 3-dimensional conformal RT (median follow-up time, 71 months). The whole bladder and the bladder wall were contoured in all patients. The primary endpoint was grade ?2 genitourinary (GU) toxicity occurring ?3 months after completion of RT. Cox regressions of time to grade ?2 toxicity were estimated separately for the entire bladder and bladder wall. Concordance probability estimates (CPE) assessed model discriminative ability. Before training the models, an external random test group of 100 men was set aside for testing. Separate analyses were performed based on the mean age (? 68 vs >68 years). Results: Age, pretreatment urinary symptoms, mean dose (entire bladder and bladder wall), and AUHC (entire bladder and bladder wall) were significant (P<.05) in multivariable analysis. Overall, bladder wall CPE values were higher than solid bladder values. The AUHC for bladder wall provided the greatest discrimination for late bladder toxicity when compared with alternative DVH points, with CPE values of 0.68 for age ?68 years and 0.81 for age >68 years. Conclusion: The AUHC method based on bladder wall volumes was superior for predicting late GU toxicity. Age >68 years was associated with late grade ?2 GU toxicity, which suggests that risk-adapted dose constraints based on age should be explored.

  6. New clues to the cause of extended main-sequence turnoffs in intermediate-age star clusters in the Magellanic Clouds

    SciTech Connect (OSTI)

    Correnti, Matteo; Goudfrooij, Paul; Kalirai, Jason S.; Girardi, Leo; Puzia, Thomas H.; Kerber, Leandro E-mail: goudfroo@stsci.edu E-mail: leo.girardi@oapd.inaf.it E-mail: lkerber@gmail.com

    2014-10-01

    We use the Wide Field Camera 3 on board the Hubble Space Telescope (HST) to obtain deep, high-resolution images of two intermediate-age star clusters in the Large Magellanic Cloud of relatively low mass (?10{sup 4} M {sub ?}) and significantly different core radii, namely NGC 2209 and NGC 2249. For comparison purposes, we also reanalyzed archival HST images of NGC 1795 and IC 2146, two other relatively low-mass star clusters. From the comparison of the observed color-magnitude diagrams with Monte Carlo simulations, we find that the main-sequence turnoff (MSTO) regions in NGC 2209 and NGC 2249 are significantly wider than that derived from simulations of simple stellar populations, while those in NGC 1795 and IC 2146 are not. We determine the evolution of the clusters' masses and escape velocities from an age of 10 Myr to the present age. We find that differences among these clusters can be explained by dynamical evolution arguments if the currently extended clusters (NGC 2209 and IC 2146) experienced stronger levels of initial mass segregation than the currently compact ones (NGC 2249 and NGC 1795). Under this assumption, we find that NGC 2209 and NGC 2249 have estimated escape velocities, V {sub esc} ? 15 km s{sup 1} at an age of 10 Myr, large enough to retain material ejected by slow winds of first-generation stars, while the two clusters that do not feature extended MSTOs have V {sub esc} ? 12 km s{sup 1} at that age. These results suggest that the extended MSTO phenomenon can be better explained by a range of stellar ages rather than a range of stellar rotation velocities or interacting binaries.

  7. Quarterly progress report on configurational diffusion of asphaltenes in fresh and aged catalyst extrudates, September 20, 1995--December 20, 1995

    SciTech Connect (OSTI)

    Guin, J.A.

    1995-12-31

    The objective of this research is to determine the relationship between the size and shape of coal and petroleum macromolecules and their diffusion rates i.e., effective diffusivities, in catalyst pore structures. That is, how do the effective intrapore diffusivities depend on molecule configuration and pore geometry. The research is divided into the following tasks: (1) relationship between effective intrapore diffusion coefficients, molecular size and pore geometry; (2) effects of solvent composition, solute concentration, and temperature on the molecular configuration and diffusion rate of coal and petroleum asphaltenes in catalysts pore; and (3) assessment of diffusional limitations in aged catalysts. This quarter, the GPC column efficiency was rechecked by using acetone injection. The calibration curve for the GPC was rechecked through polystyrene standards with narrow molecular weight distributions. Some experiments on adsorption and diffusion of coal asphaltenes through porous catalysts were performed. The asphaltenes were grouped into nine fractions with the concentration being determined via GPC. It was found that the uptake rate for one asphaltene fraction is different from those for other fractions. Comparison of experimental uptake data shows a difference in hindered diffusion behavior between petroleum asphaltenes and coal asphaltenes.

  8. Thermal Release of 3He from Tritium Aged LaNi4.25Al0.75 Hydride

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Staack, Gregory C.; Crowder, Mark L.; Klein, James E.

    2015-02-01

    Recently, the demand for He-3 has increased dramatically due to widespread use in nuclear nonproliferation, cryogenic, and medical applications. Essentially all of the world’s supply of He-3 is created by the radiolytic decay of tritium. The Savannah River Site Tritium Facilities (SRS-TF) utilizes LANA.75 in the tritium process to store hydrogen isotopes. The vast majority of He-3 “born” from tritium stored in LANA.75 is trapped in the hydride metal matrix. The SRS-TF has multiple LANA.75 tritium storage beds that have been retired from service with significant quantities of He-3 trapped in the metal. To support He-3 recovery, the Savannah Rivermore » National Laboratory (SRNL) conducted thermogravimetric analysis coupled with mass spectrometry (TGA-MS) on a tritium aged LANA.75 sample. TGA-MS testing was performed in an argon environment. Prior to testing, the sample was isotopically exchanged with deuterium to reduce residual tritium and passivated with air to alleviate pyrophoric concerns associated with handling the material outside of an inert glovebox. Analyses indicated that gas release from this sample was bimodal, with peaks near 220 and 490°C. The first peak consisted of both He-3 and residual hydrogen isotopes, the second was primarily He-3. The bulk of the gas was released by 600 °C« less

  9. Bayesian Inference for Time Trends in Parameter Values: Case Study for the Ageing PSA Network of the European Commission

    SciTech Connect (OSTI)

    Dana L. Kelly; Albert Malkhasyan

    2010-06-01

    There is a nearly ubiquitous assumption in PSA that parameter values are at least piecewise-constant in time. As a result, Bayesian inference tends to incorporate many years of plant operation, over which there have been significant changes in plant operational and maintenance practices, plant management, etc. These changes can cause significant changes in parameter values over time; however, failure to perform Bayesian inference in the proper time-dependent framework can mask these changes. Failure to question the assumption of constant parameter values, and failure to perform Bayesian inference in the proper time-dependent framework were noted as important issues in NUREG/CR-6813, performed for the U. S. Nuclear Regulatory Commissions Advisory Committee on Reactor Safeguards in 2003. That report noted that industry lacks tools to perform time-trend analysis with Bayesian updating. This paper describes an application of time-dependent Bayesian inference methods developed for the European Commission Ageing PSA Network. These methods utilize open-source software, implementing Markov chain Monte Carlo sampling. The paper also illustrates the development of a generic prior distribution, which incorporates multiple sources of generic data via weighting factors that address differences in key influences, such as vendor, component boundaries, conditions of the operating environment, etc.

  10. Modeling the formation and aging of secondary organic aerosols in Los Angeles during CalNex 2010

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hayes, P. L.; Carlton, A. G.; Baker, K. R.; Ahmadov, R.; Washenfelder, R. A.; Alvarez, S.; Rappenglück, B.; Gilman, J. B.; Kuster, W. C.; de Gouw, J. A.; et al

    2014-12-20

    Four different parameterizations for the formation and evolution of secondary organic aerosol (SOA) are evaluated using a 0-D box model representing the Los Angeles Metropolitan Region during the CalNex 2010 field campaign. We constrain the model predictions with measurements from several platforms and compare predictions with particle and gas-phase observations from the CalNex Pasadena ground site. That site provides a unique opportunity to study aerosol formation close to anthropogenic emission sources with limited recirculation. The model SOA formed only from the oxidation of VOCs (V-SOA) is insufficient to explain the observed SOA concentrations, even when using SOA parameterizations with multi-generationmore » oxidation that produce much higher yields than have been observed in chamber experiments, or when increasing yields to their upper limit estimates accounting for recently reported losses of vapors to chamber walls. The Community Multiscale Air Quality (WRF-CMAQ) model (version 5.0.1) provides excellent predictions of secondary inorganic particle species but underestimates the observed SOA mass by a factor of 25 when an older VOC-only parameterization is used, which is consistent with many previous model-measurement comparisons for pre-2007 anthropogenic SOA modules in urban areas. Including SOA from primary semi-volatile and intermediate volatility organic compounds (P-S/IVOCs) following the parameterizations of Robinson et al. (2007), Grieshop et al. (2009), or Pye and Seinfeld (2010) improves model/measurement agreement for mass concentration. When comparing the three parameterizations, the Grieshop et al. (2009) parameterization more accurately reproduces both the SOA mass concentration and oxygen-to-carbon ratio inside the urban area. Our results strongly suggest that other precursors besides VOCs, such as P-S/IVOCs, are needed to explain the observed SOA concentrations in Pasadena. All the parameterizations over-predict urban SOA formation at long photochemical ages (≈ 3 days) compared to observations from multiple sites, which can lead to problems in regional and global modeling. Among the explicitly modeled VOCs, the precursor compounds that contribute the greatest SOA mass are methylbenzenes. Polycyclic aromatic hydrocarbons (PAHs) are less important precursors and contribute less than 4% of the SOA mass. The amounts of SOA mass from diesel vehicles, gasoline vehicles, and cooking emissions are estimated to be 16–27, 35–61, and 19–35%, respectively, depending on the parameterization used, which is consistent with the observed fossil fraction of urban SOA, 71 (±3) %. In-basin biogenic VOCs are predicted to contribute only a few percent to SOA. A regional SOA background of approximately 2.1 μg m−3 is also present due to the long distance transport of highly aged OA. The percentage of SOA from diesel vehicle emissions is the same, within the estimated uncertainty, as reported in previous work that analyzed the weekly cycles in OA concentrations (Bahreini et al., 2012; Hayes et al., 2013). However, the modeling work presented here suggests a strong anthropogenic source of modern carbon in SOA, due to cooking emissions, which was not accounted for in those previous studies. Lastly, this work adapts a simple two-parameter model to predict SOA concentration and O/C from urban emissions. This model successfully predicts SOA concentration, and the optimal parameter combination is very similar to that found for Mexico City. This approach provides a computationally inexpensive method for predicting urban SOA in global and climate models. We estimate pollution SOA to account for 26 Tg yr−1 of SOA globally, or 17% of global SOA, 1/3 of which is likely to be non-fossil.« less

  11. FORMATION AND EVOLUTION OF NUCLEAR STAR CLUSTERS WITH IN SITU STAR FORMATION: NUCLEAR CORES AND AGE SEGREGATION

    SciTech Connect (OSTI)

    Aharon, Danor; Perets, Hagai B.

    2015-02-01

    Nuclear stellar cluster (NSCs) are known to exist around massive black holes (MBHs) in galactic nuclei. Two formation scenarios were suggested for their origin: (1) buildup of NSCs from consecutive infall of stellar clusters and (2) continuous in situ star formation. Though the cluster infall scenario has been extensively studied, the in situ formation scenario has been hardly explored. Here we use Fokker-Planck (FP) calculations to study the effects of star formation on the buildup of NSCs and its implications for their long-term evolution and their resulting structure. We use the FP equation to describe the evolution of stellar populations and add appropriate source terms to account for the effects of newly formed stars. We show that continuous star formation even 1-2 pc away from the MBH can lead to the buildup of an NSC with properties similar to those of the Milky Way NSC. We find that the structure of the old stellar population in the NSC with in situ star formation could be very similar to the steady-state Bahcall-Wolf cuspy structure. However, its younger populations do not yet achieve a steady state. In particular, formed/evolved NSCs with in situ star formation contain differential age-segregated stellar populations that are not yet fully mixed. Younger stellar populations formed in the outer regions of the NSC have a cuspy structure toward the NSC outskirts, while showing a core-like distribution inward, with younger populations having larger core sizes. In principal, such a structure can give rise to an apparent core-like radial distribution of younger stars, as observed in the Galactic center.

  12. Material property evaluations of bimetallic welds, stainless steel saw fusion lines, and materials affected by dynamic strain aging

    SciTech Connect (OSTI)

    Rudland, D.; Scott, P.; Marschall, C.; Wilkowski, G.

    1997-04-01

    Pipe fracture analyses can often reasonably predict the behavior of flawed piping. However, there are material applications with uncertainties in fracture behavior. This paper summarizes work on three such cases. First, the fracture behavior of bimetallic welds are discussed. The purpose of the study was to determine if current fracture analyses can predict the response of pipe with flaws in bimetallic welds. The weld joined sections of A516 Grade 70 carbon steel to F316 stainless steel. The crack was along the carbon steel base metal to Inconel 182 weld metal fusion line. Material properties from tensile and C(T) specimens were used to predict large pipe response. The major conclusion from the work is that fracture behavior of the weld could be evaluated with reasonable accuracy using properties of the carbon steel pipe and conventional J-estimation analyses. However, results may not be generally true for all bimetallic welds. Second, the toughness of austenitic steel submerged-arc weld (SAW) fusion lines is discussed. During large-scale pipe tests with flaws in the center of the SAW, the crack tended to grow into the fusion line. The fracture toughness of the base metal, the SAW, and the fusion line were determined and compared. The major conclusion reached is that although the fusion line had a higher initiation toughness than the weld metal, the fusion-line J-R curve reached a steady-state value while the SAW J-R curve increased. Last, carbon steel fracture experiments containing circumferential flaws with periods of unstable crack jumps during steady ductile tearing are discussed. These instabilities are believed to be due to dynamic strain aging (DSA). The paper discusses DSA, a screening criteria developed to predict DSA, and the ability of the current J-based methodologies to assess the effect of these crack instabilities. The effect of loading rate on the strength and toughness of several different carbon steel pipes at LWR temperatures is also discussed.

  13. CSR behavior and aging model for the Viton© Fluorelastomer O-rings in the 9975 shipping package

    SciTech Connect (OSTI)

    Mcwilliams, A. J.; Daugherty, W. L.; Skidmore, T. E.

    2015-12-01

    The 9975 Type B shipping package is used within the DOE complex for shipping special nuclear materials. This package is re-certified annually in accordance with Safety Analysis Report for Packaging (SARP) requirements. The package is also used at the Savannah River Site as part of the long-term storage configuration of special nuclear materials. As such, the packages do not undergo annual recertification during storage, with uncertainty as to how long some of the package components will meet their functional requirements in the storage environment. The packages are currently approved for up to 15 years storage, and work continues to provide a technical basis to extend that period. This report describes efforts by the Savannah River National Laboratory (SRNL) to extend the service life estimate of Viton® GLT and GLT-S fluoroelastomer O-rings used in the 9975 shipping package. O-rings of both GLT and GLT-S compositions are undergoing accelerated aging at elevated temperature, and are periodically tested for compression stress relaxation (CSR) behavior. The CSR behavior of O-rings was evaluated at temperatures from 175 to 400 °F. These collective data were used to develop predictive models for extrapolation of CSR behavior to relevant service temperatures (< 156 °F). The predictive model developed from the CSR data conservatively indicates a service life of approximately 37 years for Viton GLT O-rings at the maximum effective service temperature of 156 °F. The estimated service life for Viton GLT-S O-rings is significantly longer.

  14. Modeling the formation and aging of secondary organic aerosols in Los Angeles during CalNex 2010

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hayes, P. L.; Carlton, A. G.; Baker, K. R.; Ahmadov, R.; Washenfelder, R. A.; Alvarez, S.; Rappenglück, B.; Gilman, J. B.; Kuster, W. C.; de Gouw, J. A.; et al

    2015-05-26

    Four different literature parameterizations for the formation and evolution of urban secondary organic aerosol (SOA) frequently used in 3-D models are evaluated using a 0-D box model representing the Los Angeles metropolitan region during the California Research at the Nexus of Air Quality and Climate Change (CalNex) 2010 campaign. We constrain the model predictions with measurements from several platforms and compare predictions with particle- and gas-phase observations from the CalNex Pasadena ground site. That site provides a unique opportunity to study aerosol formation close to anthropogenic emission sources with limited recirculation. The model SOA that formed only from the oxidationmore » of VOCs (V-SOA) is insufficient to explain the observed SOA concentrations, even when using SOA parameterizations with multi-generation oxidation that produce much higher yields than have been observed in chamber experiments, or when increasing yields to their upper limit estimates accounting for recently reported losses of vapors to chamber walls. The Community Multiscale Air Quality (WRF-CMAQ) model (version 5.0.1) provides excellent predictions of secondary inorganic particle species but underestimates the observed SOA mass by a factor of 25 when an older VOC-only parameterization is used, which is consistent with many previous model–measurement comparisons for pre-2007 anthropogenic SOA modules in urban areas. Including SOA from primary semi-volatile and intermediate-volatility organic compounds (P-S/IVOCs) following the parameterizations of Robinson et al. (2007), Grieshop et al. (2009), or Pye and Seinfeld (2010) improves model–measurement agreement for mass concentration. The results from the three parameterizations show large differences (e.g., a factor of 3 in SOA mass) and are not well constrained, underscoring the current uncertainties in this area. Our results strongly suggest that other precursors besides VOCs, such as P-S/IVOCs, are needed to explain the observed SOA concentrations in Pasadena. All the recent parameterizations overpredict urban SOA formation at long photochemical ages (≈ 3 days) compared to observations from multiple sites, which can lead to problems in regional and especially global modeling. However, reducing IVOC emissions by one-half in the model to better match recent IVOC measurements improves SOA predictions at these long photochemical ages. Among the explicitly modeled VOCs, the precursor compounds that contribute the greatest SOA mass are methylbenzenes. Measured polycyclic aromatic hydrocarbons (naphthalenes) contribute 0.7% of the modeled SOA mass. The amounts of SOA mass from diesel vehicles, gasoline vehicles, and cooking emissions are estimated to be 16–27, 35–61, and 19–35%, respectively, depending on the parameterization used, which is consistent with the observed fossil fraction of urban SOA, 71(±3) %. The relative contribution of each source is uncertain by almost a factor of 2 depending on the parameterization used. In-basin biogenic VOCs are predicted to contribute only a few percent to SOA. A regional SOA background of approximately 2.1 μg m−3 is also present due to the long-distance transport of highly aged OA, likely with a substantial contribution from regional biogenic SOA. The percentage of SOA from diesel vehicle emissions is the same, within the estimated uncertainty, as reported in previous work that analyzed the weekly cycles in OA concentrations (Bahreini et al., 2012; Hayes et al., 2013). However, the modeling work presented here suggests a strong anthropogenic source of modern carbon in SOA, due to cooking emissions, which was not accounted for in those previous studies and which is higher on weekends. Lastly, this work adapts a simple two-parameter model to predict SOA concentration and O/C from urban emissions. This model successfully predicts SOA concentration, and the optimal parameter combination is very similar to that found for Mexico City. This approach provides a computationally inexpensive method for predicting urban SOA in global and climate models. We estimate pollution SOA to account for 26 Tg yr−1 of SOA globally, or 17% of global SOA, one-third of which is likely to be non-fossil.« less

  15. Radiation May Indirectly Impair Growth Resulting in Reduced Standing Height via Subclinical Inflammation in Atomic-Bomb Survivors Exposed at Young Ages

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Nakashima, Eiji; Neriishi, Kazuo; Hsu, Wan-Ling

    2015-01-01

    For youngmore » atomic-bomb (A-bomb) survivors, A-bomb radiation’s (total) effect on standing height is thought to comprise the sum of direct effect and indirect effect via inflammation. With the data of five inflammatory markers—white blood cell count, sialic acid, corrected erythrocyte sedimentation rate (ESR), α 1 globulin, and α 2 globulin—obtained in adulthood during the period 1988 to 1992, a summary inflammatory index was constructed as a surrogate for the five subclinical inflammatory markers. For 3,327 A-bomb survivors exposed at ages of less than 25 years, a structural equation model was analyzed to measure direct radiation effects on adult height as well as mediating effect of radiation via inflammation on the height after adjustment for other risk factors, smoking, cancer, inflammatory disease, obesity, and diabetes mellitus. The mediation proportion of the radiation effect on height via inflammation was approximately 5% for both sexes for all ages, and indirect dose effects via inflammation were statistically significant for both sexes combined and for females exposed at ages 0 to 5 years. Indirect dose effects for all ages via sialic acid, corrected ESR, and α 2 globulin were marginally significant for both sexes combined and for females. These proportions are likely underestimated.« less

  16. Effects of ageing on different binders for retouching and on some binder-pigment combinations used for restoration of wall paintings

    SciTech Connect (OSTI)

    Ropret, P. Zoubek, R.; Skapin, A. Sever Bukovec, P.

    2007-11-15

    In restoration of colour layers, the selection of the most appropriate retouching binder is a very important step that may have a crucial impact on materials durability. As different weather conditions can have versatile influence on stability of colour layers, we determined the effect of ageing on carefully selected samples of binders (Tylose, Klucel, ammonium caseinate, gum arabicum, fish and skin glues and some other synthetic binders) as well as on several binder-pigment combinations (the pigments in combinations being cinnabar, green earth and smalt). The samples were subjected to accelerated ageing tests in climatic chambers. In these tests the temperature and the relative humidity were daily oscillating between - 20 deg. C and 50 deg. C and 50% to 90%, respectively, for a period of one month. Then the samples were exposed to UV and visible light generated by a metal halide lamp for a month. The differences in microstructure before and after ageing were determined by optical and scanning electron microscopy, while the ageing of the organic structures in binders was investigated by Fourier transform infrared (FTIR) microscopy.

  17. Impact of zeolite aging in hot liquid water on activity for acid-catalyzed dehydration of alcohols

    SciTech Connect (OSTI)

    Vjunov, Aleksei; Derewinski, Miroslaw A.; Fulton, John L.; Camaioni, Donald M.; Lercher, Johannes A.

    2015-08-19

    The catalytic performance of zeolite in aqueous medium depends on a multitude of factors, such as the concentration and distribution of active sites and framework integrity. Al Kedge extended Xray absorption fine structure and 27Al MAS NMR spectroscopies in combination with DFT calculations are used to determine the distribution of tetrahedral Al sites both qualitatively and quantitatively for both parent and 48 h 160 C water treated HBEA catalysts. There is no evidence of Al coordination modification after aging in water. The distribution and concentration of Al Tsites, active centers for the dehydration of cyclohexanol, do not markedly impact the catalytic performance in water, because the Brnsted acidic protons are present in the form of hydrated hydronium ions and thus have very similar acid properties. The results suggest that all Brnsted acid sites are equally active in aqueous medium. The decrease of zeolite catalytic performance after water treatment is attributed to the reduced concentration of Brnsted acid sites. Increasing the stability of pore walls and decreasing the rate of SiOSi group hydrolysis may result in improved apparent zeolite catalytic performance in aqueous medium. Authors thank B. W. Arey (PNNL) for HIM measurements, T. Huthwelker for support during Al XAFS measurements at the Swiss Light Source (PSI, Switzerland), J. Z. Hu and S. D. Burton (PNNL) for support during NMR experiments. This work was supported by the U. S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences & Biosciences. MD acknowledges support by the Materials Synthesis and Simulation Across Scales (MS3 Initiative) conducted under Laboratory Directed Research & Development Program at PNNL. HIM imaging and NMR experiments were performed at the Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by the DOE Office of Science, Office of Biological and Environmental Research, located at Pacific Northwest National Laboratory (PNNL). PNNL is a multiprogram national laboratory operated for the DOE by Battelle Memorial Institute under contract # DE-AC05-76RL0-1830

  18. Universities Across the United States Make Strides in Energy...

    Broader source: Energy.gov (indexed) [DOE]

    Energized students on campuses across the United States are learning at a young age just how much money and energy they can save by taking some easy, energy-saving steps. A new ...

  19. Petrography, age, and paleomagnetism of basalt lava flows in coreholes Well 80, NRF 89-04, NRF 89-05, and ICPP 123, Idaho National Engineering Laboratory

    SciTech Connect (OSTI)

    Lanphere, M.A.; Champion, D.E.; Kuntz, M.A.

    1993-12-31

    The petrography, age, and paleomagnetism were determined on basalt from 23 lava flows comprising about 1200 feet of core from four coreholes in the Idaho National Engineering Laboratory (ML). The four coreholes are located in the southwestern part of the INEL. Paleomagnetic measurements were made on 192 samples of basalt, and K-Ar ages were measured on 19 basalt samples. All of the samples have normal magnetic polarity and were erupted during the Brunhes Normal Polarity Epoch. Basalt lava flows in ICPP 123 can be satisfactorily correlated with lava flows in the previously studied corehole at Site E, but correlations cannot be made with confidence between ICPP 123 and the other three coreholes studied in this investigation.

  20. Developing 226Ra and 227Ac age-dating techniques for nuclear forensics to gain insight from concordant and non-concordant radiochronometers

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kayzar, Theresa M.; Williams, Ross W.

    2015-09-26

    The model age or ‘date of purification’ of a nuclear material is an important nuclear forensic signature. In this study, chemical separation and MC-ICP-MS measurement techniques were developed for 226 Ra and 227Ac: grand-daughter nuclides in the 238U and 235U decay chains respectively. The 230Th-234U, 226Ra-238U, 231Pa-235U, and 227Ac-235U radiochronometers were used to calculate model ages for CRM-U100 standard reference material and two highly-enriched pieces of uranium metal from the International Technical Working Group Round Robin 3 Exercise. In conclusion, the results demonstrate the accuracy of the 226Ra-238U and 227Ac-235U chronometers and provide information about nuclide migration during uranium processing.

  1. The overthrusted Zaza Terrane of middle Cretaceous over the North American continental carbonate rocks of upper Jurassic-Lower Cretaceous age - relationships to oil generation

    SciTech Connect (OSTI)

    Echevarria Rodriguez, G.; Castro, J.A.; Amaro, S.V.

    1996-08-01

    The Zaza Terrane is part of the Caribbean plate thrust over the southern edge of the North American basinal and platform carbonate rocks of upper Jurassic-Lower Cretaceous age. Zaza Terrane are volcanic and ophiolitic rocks of Cretaceous age. The ophiolites are mostly serpentines which behave as reservoirs and seals. All Cuban oil fields are either within Zaza Terrane or basinal carbonates underneath, or not far away to the north of the thrust contacts. It appears that the overthrusting of the Zaza Terrane caused the generation of oil in the basinal carbonate source rocks underneath, due to the increase of rock thickness which lowered the oil window to a deeper position and increased the geothermal gradient. Oil generation was after thrusting, during post-orogenic. API gravity of oil is light toward the south and heavy to very heavy to the north. Source rocks to the south are probably of terrigenous origin.

  2. Light Water Reactor Sustainability (LWRS) Program – Non-Destructive Evaluation (NDE) R&D Roadmap for Determining Remaining Useful Life of Aging Cables in Nuclear Power Plants

    SciTech Connect (OSTI)

    Simmons, K.L.; Ramuhali, P.; Brenchley, D.L.; Coble, J.B.; Hashemian, H.M.; Konnick, R.; Ray, S.

    2012-09-01

    Executive Summary [partial] The purpose of the non-destructive evaluation (NDE) R&D Roadmap for Cables is to support the Materials Aging and Degradation (MAaD) R&D pathway. A workshop was held to gather subject matter experts to develop the NDE R&D Roadmap for Cables. The focus of the workshop was to identify the technical gaps in detecting aging cables and predicting their remaining life expectancy. The workshop was held in Knoxville, Tennessee, on July 30, 2012, at Analysis and Measurement Services Corporation (AMS) headquarters. The workshop was attended by 30 experts in materials, electrical engineering, and NDE instrumentation development from the U.S. Nuclear Regulatory Commission (NRC), U.S. Department of Energy (DOE) National Laboratories (Oak Ridge National Laboratory, Pacific Northwest National Laboratory, Argonne National Laboratory, and Idaho National Engineering Laboratory), universities, commercial NDE service vendors and cable manufacturers, and the Electric Power Research Institute (EPRI).

  3. Effect of pre-oxidation and environmental aging on the seal strength of a novel high-temperature solid oxide fuel cell (SOFC) sealing glass with metallic interconnect

    SciTech Connect (OSTI)

    Chou, Y. S.; Stevenson, Jeffry W.; Singh, Prabhakar

    2008-09-15

    A novel high-temperature alkaline-earth silicate sealing glass was developed for solid oxide fuel cell (SOFC) applications. The glass was used to join two ferritic stainless steel coupons for strength evaluation. The steel coupons were pre-oxidized at elevated temperatures to promote thick oxide layers to simulate long-term exposure conditions. In addition, seals to as-received metal coupons were also tested after aging in oxidizing or reducing environments to simulate the actual SOFC environment. Room temperature tensile testing showed strength degradation when using pre-oxidized coupons, and more extensive degradation after aging in air. Fracture surface and microstructural analysis confirmed that the cause of degradation was formation of SrCrO4 at the outer sealing edges exposed to air.

  4. AGING EFFECTS ON THE PROPERTIES OF IMIDAZOLIUM, QUATERNARY AMMONIUM, PYRIDINIUM AND PYRROLIDINIUM-BASED IONIC LIQUIDS USED IN FUEL AND ENERGY PRODUCTION

    SciTech Connect (OSTI)

    Fox, E.

    2013-08-13

    Ionic liquids are often cited for their excellent thermal stability, a key property for their use as solvents and in the chemical processing of biofuels. However, there has been little supporting data on the long term aging effect of temperature on these materials. Imizadolium, quaternary ammonium, pyridinium, and pyrrolidnium-based ionic liquids with the bis(trifluoromethylsulfonyl)imide and bis(perfluoroethylsulfonyl)imide anions were aged for 2520 hours (15 weeks) at 200�C in air to determine the effects of an oxidizing environment on their chemical structure and thermal stability over time. It was found that the minor changes in the cation chemistry could greatly affect the properties of the ILs over time.

  5. Effect of Gaseous Impurities on Long-Term Thermal Cycling and Aging Properties of Complex Hydrides for Hydrogen Storage

    SciTech Connect (OSTI)

    Chandra, Dhanesh; Lamb, Joshua; Chien, Wen-Ming; Talekar, Anjali; and Pal, Narendra.

    2011-03-28

    This program was dedicated to understanding the effect of impurities on Long-Term Thermal Cycling and aging properties of Complex Hydrides for Hydrogen Storage. At the start of the program we found reversibility between Li2NH+LiH  LiH+LiNH2 (yielding ~5.8 wt.%H capacity). Then we tested the effect of impurity in H2 gas by pressure cycling at 255oC; first with industrial gas containing ppm levels of O2 and H2O as major impurities. Both these impurities had a significant impact on the reversibility and decreased the capacity by 2.65 wt.%H. Further increase in number of cycles from 500 to 1100 showed only a 0.2 wt%H more weight loss, showing some capacity is still maintained after a significant number of cycles. The loss of capacity is attributed to the formation of ~55 wt% LiH and ~30% Li2O, as major contaminant phases, along with the hydride Li2NH phase; suggesting loss of nitrogen during cycling. The effect of 100 ppm H2O in H2 also showed a decrease of ~2.5 wt.%H (after 560 cycles), and 100ppm O2 in H2; a loss of ~4.1 wt.%. Methane impurity (100 ppm, 100cycles), showed a very small capacity loss of 0.9 wt.%H under similar conditions. However, when Li3N was pressure cycled with 100ppmN2-H2 there were beneficial effects were observed (255oC); the reversible capacity increased to 8.4wt.%H after 853 cycles. Furthermore, with 20 mol.%N2-H2 capacity increased to ~10 wt.%H after 516 cycles. We attribute this enhancement to the reaction of nitrogen with liquid lithium during cycling as the Gibbs free energy of formation of Li3N (Go = -98.7 kJ/mol) is more negative than that of LiH (Go = -50.3 kJ/mol). We propose that the mitigation of hydrogen capacity losses is due to the destabilization of the LiH phase that tends to accumulate during cycling. Also more Li2NH phase was found in the cycled product. Mixed Alanates (3LiNH2:Li3AlH6) showed that 7 wt% hydrogen desorbed under dynamic vacuum. Equilibrium experiments (maximum 12 bar H2) showed up to 4wt% hydrogen reversibly stored in the material after the first desorption. The activation energy was found to be 51 kJ/mol, as compared to 81 kJ/mol for pure lithium alanate. It is proposed that based on the data obtained and CALPHAD modeling that the improvement in cycling is due to the formation of pure lithium (liquid at 255oC), which is able to react with nitrogen specifically forming Li3N. The presence of nitrogen in the 80/20 molar mixtures in a hydride bed along with hydrogen causes Li to form Li3N rather than LiH, and subsequently regenerates the Li2NH phase and yields a ~10 wt.%H reversibly.

  6. MID-INFRARED HIGH-CONTRAST IMAGING OF HD 114174 B: AN APPARENT AGE DISCREPANCY IN A ''SIRIUS-LIKE'' BINARY SYSTEM

    SciTech Connect (OSTI)

    Matthews, Christopher T.; Crepp, Justin R.; Skemer, Andrew; Hinz, Philip M.; Bailey, Vanessa P.; Defrere, Denis; Leisenring, Jarron; Gianninas, Alexandros; Kilic, Mukremin; Skrutskie, Michael; Esposito, Simone; Puglisi, Alfio

    2014-03-10

    We present new observations of the faint ''Sirius-like'' companion discovered to orbit HD 114174. Previous attempts to image HD 114174 B at mid-infrared wavelengths using NIRC2 at Keck have resulted in a non-detection. Our new L'-band observations taken with the Large Binocular Telescope and L/M-band InfraRed Camera recover the companion (?L = 10.15 0.15mag, ? = 0.''675 0.''016) with a high signal-to-noise ratio (10?). This measurement represents the deepest L' high-contrast imaging detection at subarcsecond separations to date, including extrasolar planets. We confirm that HD 114174 B has near-infrared colors consistent with the interpretation of a cool white dwarf (WD; J L' = 0.76 0.19mag, K L' = 0.64 0.20). New model fits to the object's spectral energy distribution indicate a temperature T {sub eff} = 4260 360K, surface gravity log g = 7.94 0.03, a cooling age t{sub c} ? 7.8Gyr, and mass M = 0.54 0.01 M {sub ?}. We find that the cooling ages given by theoretical atmospheric models do not agree with the age of HD 114174 A derived from both isochronological and gyrochronological analyses. We speculate on possible scenarios to explain the apparent age discrepancy between the primary and secondary. HD114174B is a nearby benchmark WD that will ultimately enable a dynamical mass estimate through continued Doppler and astrometric monitoring. Efforts to characterize its physical properties in detail will test theoretical atmospheric models and improve our understanding of WD evolution, cooling, and progenitor masses.

  7. In Situ GISAXS investigation of low-temperature aging in oriented surfactant-mesostructured titania thin films

    SciTech Connect (OSTI)

    Nagpure, Suraj; Das, Saikat; Garlapalli, Ravinder K.; Strzalka, Joseph; Rankin, Stephen E.

    2015-09-11

    In this study, the mechanism of forming orthogonally oriented hexagonal close packed (o-HCP) mesostructures during aging of surfactant-templated titania thin films is elucidated using in situ grazing incidence small-angle x-ray scattering (GISAXS) in a controlled-environment chamber. To promote orthogonal orientation, glass slides are modified with crosslinked Pluronic P123, to provide surfaces chemically neutral towards both blocks of mesophase template P123. At 4 °C and 80% RH, the o-HCP mesophase emerges in thin (~60 nm) films by a direct disorder-to-order transition, with no intermediate ordered mesophase. The Pluronic/titania o-HCP GISAXS intensity emerges only after ~10-12 minutes, much slower than previously reported for smallmolecule surfactants. The Avrami model applied to the data suggests 2D growth with nucleation at the start of the process with a half-life of 39.7 minutes for the aging time just after the induction period of 7 minutes followed by a period consistent with 1D growth kinetics. Surprisingly, films that are thicker (~250 nm) or cast on unmodified slides form o-HCP mesophase domains, but by a different mechanism (2D growth with continuous nucleation) with faster and less complete orthogonal alignment. Thus, the o-HCP mesophase is favored not only 2 by modifying the substrate, but also by aging at 4 °C, which is below the lower consolute temperature (LCST) of the poly(propylene oxide) block of P123. Consistent with this, in situ GISAXS shows that films aged at room temperature (above the LCST of the PPO block) have randomly oriented HCP mesostructure.

  8. The Carina project. VII. Toward the breaking of the age-metallicity degeneracy of red giant branch stars using the C {sub U,} {sub B,} {sub I} index

    SciTech Connect (OSTI)

    Monelli, M.; Milone, A. P.; Gallart, C.; Aparicio, A. [Instituto de Astrofsica de Canarias, Calle Via Lactea s/n, E-38205 La Laguna, Tenerife (Spain); Fabrizio, M.; Cassisi, S.; Buonanno, R. [Istituto Nazionale di Astrofisica-Osservatorio Astronomico Collurania, Via M. Maggini, I-64100 Teramo (Italy); Bono, G. [Dipartimento di Fisica, Universit di Roma Tor Vergata, Via della Ricerca Scientifica 1, I-00133 Rome (Italy); Stetson, P. B. [Dominion Astrophysical Observatory, NRC-Herzberg, 5071 West Saanich Road, Victoria, BC, V9E 2E7 (Canada); Walker, A. R. [Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory, Casilla 603, La Serena (Chile); Nonino, M. [Istituto Nazionale di Astrofisica-Osservatorio Astronomico di Trieste, Via G. B. Tiepolo 11, I-40131 Trieste (Italy); Dall'Ora, M. [INAFOsservatorio Astronomico di Capodimonte, Salita Moiariello 16, I-80131 Napoli (Italy); Ferraro, I.; Iannicola, G.; Pulone, L. [Istituto Nazionale di Astrofisica-Osservatorio Astronomico di Roma, Via Frascati 33, Monte Porzio Catone, I-00044 Rome (Italy); Thvenin, F., E-mail: monelli@iac.es [Universit de Nice Sophia-antipolis, CNRS, Observatoire de la Cte d'Azur, Laboratoire Lagrange, BP 4229, F-06304 Nice (France)

    2014-12-01

    We present an analysis of photometric and spectroscopic data of the Carina dSph galaxy, testing a new approach similar to that used to disentangle multiple populations in Galactic globular clusters (GCs). We show that a proper color combination is able to separate a significant fraction of the red giant branch (RGB) of the two main Carina populations (the old one, ?12 Gyr, and the intermediate-age one, 4-8 Gyr). In particular, the c {sub U,} {sub B,} {sub I} = (U B) (B I) pseudo-color allows us to follow the RGB of both populations along a relevant portion of the RGB. We find that the oldest stars have a more negative c {sub U,} {sub B,} {sub I} pseudo-color than intermediate-age ones. We correlate the pseudo-color of RGB stars with their chemical properties, finding a significant trend between the iron content and the c {sub U,} {sub B,} {sub I}. Stars belonging to the old population are systematically more metal-poor ([Fe/H] =2.32 0.08 dex) than the intermediate-age ones ([Fe/H] =1.82 0.03 dex). This gives solid evidence of the chemical evolution history of this galaxy, and we have a new diagnostic that can allow us to break the age-metallicity degeneracy of H-burning advanced evolutionary phases. We compared the distribution of stars in the c {sub U,} {sub B,} {sub I} plane with theoretical isochrones, finding that no satisfactory agreement can be reached with models developed in a theoretical framework based on standard heavy element distributions. Finally, we discuss possible systematic differences when compared with multiple populations in GCs.

  9. Influence of multi-step heat treatments in creep age forming of 7075 aluminum alloy: Optimization for springback, strength and exfoliation corrosion

    SciTech Connect (OSTI)

    Arabi Jeshvaghani, R.; Zohdi, H.; Shahverdi, H.R.; Bozorg, M.; Hadavi, S.M.M.

    2012-11-15

    Multi-step heat treatments comprise of high temperature forming (150 Degree-Sign C/24 h plus 190 Degree-Sign C for several minutes) and subsequent low temperature forming (120 Degree-Sign C for 24 h) is developed in creep age forming of 7075 aluminum alloy to decrease springback and exfoliation corrosion susceptibility without reduction in tensile properties. The results show that the multi-step heat treatment gives the low springback and the best combination of exfoliation corrosion resistance and tensile strength. The lower springback is attributed to the dislocation recovery and more stress relaxation at higher temperature. Transmission electron microscopy observations show that corrosion resistance is improved due to the enlargement in the size and the inter-particle distance of the grain boundaries precipitates. Furthermore, the achievement of the high strength is related to the uniform distribution of ultrafine {eta} Prime precipitates within grains. - Highlights: Black-Right-Pointing-Pointer Creep age forming developed for manufacturing of aircraft wing panels by aluminum alloy. Black-Right-Pointing-Pointer A good combination of properties with minimal springback is required in this component. Black-Right-Pointing-Pointer This requirement can be improved through the appropriate heat treatments. Black-Right-Pointing-Pointer Multi-step cycles developed in creep age forming of AA7075 for improving of springback and properties. Black-Right-Pointing-Pointer Results indicate simultaneous enhancing the properties and shape accuracy (lower springback).

  10. Assessment of retrogression and re-aging treatment on microstructural and mechanical properties of Al-Zn-Mg-Cu P/M alloy

    SciTech Connect (OSTI)

    Naeem, Haider T.; Mohammad, Kahtan S.; Hussin, Kamarudin; Tan, T. Qing; Idris, M. Sobri

    2015-05-15

    In order to understand the importance of the retrogression and re-aging as a heat treatment for improving microstructural and mechanical properties of the Al-Zn-Mg-Cu powder metallurgy alloys, Al-Zn-Mg-Cu-Fe-Cr alloys were fabricated from the elemental powders. Green compacts are compressed under compaction pressure about 370 MPa. The sintering process carried out for the samples of aluminum alloys at temperature was 650°C under argon atmosphere for two hours. The sintered compacts were subjected into homogenizing condition at 470°C for 1.5 hours and then aged at 120°C for 24 hours (T6 temper) after that it carried out the retrogressed at 180°C for 30 min., and then re-aged at 120°C for 24 hours (RRA). Observations microstructures were examined using optical, scanning electron microscopy coupled with energy dispersive spectroscopy and X-ray diffraction. Density and porosity content was conducted for the samples of alloys. The result showing that the highest Vickers hardness exhibited for an Al-Zn-Mg-Cu alloy after underwent the retrogression and reaging treatment. Increasing in hardness was because of the precipitation hardening through precipitate the (Mg Zn) and (Mg{sub 2}Zn{sub 11}) phases during matrix of aluminum-alloy.

  11. Thermal Aging Study of a Dow Corning SE 1700 Porous Structure Made by Direct Ink Writing: 1-Year Results and Long-Term Predictions

    SciTech Connect (OSTI)

    Small, Ward; Pearson, Mark A.; Maiti, Amitesh; Metz, Thomas R.; Duoss, Eric B.; Wilson, Thomas S.

    2015-11-13

    Dow Corning SE 1700 (reinforced polydimethylsiloxane) porous structures were made by direct ink writing (DIW). The specimens (~50% porosity) were subjected to various compressive strains (15, 30, 45%) and temperatures (room temperature, 35, 50, 70°C) in a nitrogen atmosphere (active purge) for 1 year. Compression set and load retention of the aged specimens were measured periodically during the study. Compression set increased with strain and temperature. After 1 year, specimens aged at room temperature, 35, and 50°C showed ~10% compression set (relative to the applied compressive deflection), while those aged at 70°C showed 20-40%. Due to the increasing compression set, load retention decreased with temperature, ranging from ~90% at room temperature to ~60-80% at 70°C. Long-term compression set and load retention at room temperature were predicted by applying time-temperature superposition (TTS). The predictions show compression set relative to the compressive deflection will be ~10-15% with ~70-90% load retention after 50 years at 15-45% strain, suggesting the material will continue to be mechanically functional. Comparison of the results to previously acquired data for cellular (M97*, M9760, M9763) and RTV (S5370) silicone foams suggests that the SE 1700 DIW porous specimens are on par with, or outperform, the legacy foams.

  12. A Reanalysis of Curvature in the Dose Response for Cancer and Modifications by Age at Exposure Following Radiation Therapy for Benign Disease

    SciTech Connect (OSTI)

    Little, Mark P.; Stovall, Marilyn; Smith, Susan A.; Kleinerman, Ruth A.

    2013-02-01

    Purpose: To assess the shape of the dose response for various cancer endpoints and modifiers by age and time. Methods and Materials: Reanalysis of the US peptic ulcer data testing for heterogeneity of radiogenic risk by cancer endpoint (stomach, pancreas, lung, leukemia, all other). Results: There are statistically significant (P<.05) excess risks for all cancer and for lung cancer and borderline statistically significant risks for stomach cancer (P=.07), and leukemia (P=.06), with excess relative risks Gy{sup -1} of 0.024 (95% confidence interval [CI] 0.011, 0.039), 0.559 (95% CI 0.221, 1.021), 0.042 (95% CI -0.002, 0.119), and 1.087 (95% CI -0.018, 4.925), respectively. There is statistically significant (P=.007) excess risk of pancreatic cancer when adjusted for dose-response curvature. General downward curvature is apparent in the dose response, statistically significant (P<.05) for all cancers, pancreatic cancer, and all other cancers (ie, other than stomach, pancreas, lung, leukemia). There are indications of reduction in relative risk with increasing age at exposure (for all cancers, pancreatic cancer), but no evidence for quadratic variations in relative risk with age at exposure. If a linear-exponential dose response is used, there is no significant heterogeneity in the dose response among the 5 endpoints considered or in the speed of variation of relative risk with age at exposure. The risks are generally consistent with those observed in the Japanese atomic bomb survivors and in groups of nuclear workers. Conclusions: There are excess risks for various malignancies in this data set. Generally there is a marked downward curvature in the dose response and significant reduction in relative risk with increasing age at exposure. The consistency of risks with those observed in the Japanese atomic bomb survivors and in groups of nuclear workers implies that there may be little sparing effect of fractionation of dose or low-dose-rate exposure.

  13. GRIZZLY Model of Multi-Reactive Species Diffusion, Moisture/Heat Transfer and Alkali-Silica Reaction for Simulating Concrete Aging and Degradation

    SciTech Connect (OSTI)

    Huang, Hai; Spencer, Benjamin W.; Cai, Guowei

    2015-09-01

    Concrete is widely used in the construction of nuclear facilities because of its structural strength and its ability to shield radiation. The use of concrete in nuclear power plants for containment and shielding of radiation and radioactive materials has made its performance crucial for the safe operation of the facility. As such, when life extension is considered for nuclear power plants, it is critical to have accurate and reliable predictive tools to address concerns related to various aging processes of concrete structures and the capacity of structures subjected to age-related degradation. The goal of this report is to document the progress of the development and implementation of a fully coupled thermo-hydro-mechanical-chemical model in GRIZZLY code with the ultimate goal to reliably simulate and predict long-term performance and response of aged NPP concrete structures subjected to a number of aging mechanisms including external chemical attacks and volume-changing chemical reactions within concrete structures induced by alkali-silica reactions and long-term exposure to irradiation. Based on a number of survey reports of concrete aging mechanisms relevant to nuclear power plants and recommendations from researchers in concrete community, we’ve implemented three modules during FY15 in GRIZZLY code, (1) multi-species reactive diffusion model within cement materials; (2) coupled moisture and heat transfer model in concrete; and (3) anisotropic, stress-dependent, alkali-silica reaction induced swelling model. The multi-species reactive diffusion model was implemented with the objective to model aging of concrete structures subjected to aggressive external chemical attacks (e.g., chloride attack, sulfate attack, etc.). It considers multiple processes relevant to external chemical attacks such as diffusion of ions in aqueous phase within pore spaces, equilibrium chemical speciation reactions and kinetic mineral dissolution/precipitation. The moisture/heat transfer module was implemented to simulate long-term spatial and temporal evolutions of the moisture and temperature fields within concrete structures at both room and elevated temperatures. The ASR swelling model implemented in GRIZZLY code can simulate anisotropic expansions of ASR gel under either uniaxial, biaxial and triaxial stress states, and can be run simultaneously with the moisture/heat transfer model and coupled with various elastic/inelastic solid mechanics models that were implemented in GRIZZLY code previously. This report provides detailed descriptions of the governing equations, constitutive equations and numerical algorithms of the three modules implemented in GRIZZLY during FY15, simulation results of example problems and model validation results by comparing simulations with available experimental data reported in the literature. The close match between the experiments and simulations clearly demonstrate the potential of GRIZZLY code for reliable evaluation and prediction of long-term performance and response of aged concrete structures in nuclear power plants.

  14. International Atomic Energy Agency specialists meeting on experience in ageing, maintenance, and modernization of instrumentation and control systems for improving nuclear power plant availability

    SciTech Connect (OSTI)

    Not Available

    1993-10-01

    This report presents the proceedings of the Specialist`s Meeting on Experience in Aging, Maintenance and Modernization of Instrumentation and Control Systems for Improving Nuclear Power Plant Availability that was held at the Ramada Inn in Rockville, Maryland on May 5--7, 1993. The Meeting was presented in cooperation with the Electric Power Research Institute, Oak Ridge National Laboratory and the International Atomic Energy Agency. There were approximately 65 participants from 13 countries at the Meeting. Individual reports have been cataloged separately.

  15. Milestone Report - M4FT-15OR0312026 - Complete NO and NO2 aging of AgZ

    SciTech Connect (OSTI)

    Bruffey, Stephanie H.; Patton, Kaara K.; Walker, Jr, Joseph Franklin; Jubin, Robert Thomas

    2015-03-31

    In an off-gas system within a nuclear fuel reprocessing plant, any capture material will be exposed to a gas stream for months at a time. This gas stream may be at elevated temperature and could contain water, NOx gas, or a variety of other constituents that comprise the off-gas stream. For this reason, it is important to understand the effects of long-term exposure, or aging, on proposed capture materials. One material under consideration is silver-exchanged mordenite (AgZ). The aim of this study was to determine the effect of extended exposure at 150C to an air stream containing NO on the iodine capture capacity of the hydrogen reduced form of AgZ designated as Ag0Z. The study was originally also intended to expand on the static NO2 aging studies by exposing Ag0Z to a flowing stream of NO2 for an extended period of time, but those tests were delayed due to NO2 production schedules by the gas vendor. Unreduced silver mordenite has a loading capacity of approximately 25 mg I/g AgZ and that capacity is increased to 100 mg I/g Ag0Z upon reduction. It appears that extended exposure of AgZ to 1% NO at 150C may not only neutralize the increased capacity gained by reduction, but perhaps degrade the sorbent even further. Loss of 80% of sorbent capacity and surface area was observed after 8 weeks of exposure to a 1% NO stream at 150C. Investigations continue into the effects of aging by off-gas components on iodine sorbents. Future work will age silver mordenite with streams containing NO2. As the simulated off-gas streams become more complex and more corrosive, the ability of AgZ to withstand conditions present in off-gas streams will be more fully known.

  16. A cohort study of developmental polychlorinated biphenyl (PCB) exposure in relation to post-vaccination antibody response at 6-months of age

    SciTech Connect (OSTI)

    Jusko, Todd A.; De Roos, Anneclaire J.; Schwartz, Stephen M.; Program in Epidemiology, Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA ; Paige Lawrence, B.; Palkovicova, Lubica; Nemessanyi, Tomas; Drobna, Beata; Fabisikova, Anna; Kocan, Anton; Sonneborn, Dean; Jahnova, Eva; Kavanagh, Terrance J.; Trnovec, Tomas; Hertz-Picciotto, Irva

    2010-05-15

    Background: Extensive experimental data in animals indicate that exposure to polychlorinated biphenyls (PCBs) during pregnancy leads to changes in offspring immune function during the postnatal period. Whether developmental PCB exposure influences immunologic development in humans has received little study. Methods: The study population was 384 mother-infant pairs recruited from two districts of eastern Slovakia for whom prospectively collected maternal, cord, and 6-month infant blood specimens were available. Several PCB congeners were measured in maternal, cord, and 6-month infant sera by high-resolution gas chromatography with electron capture detection. Concentrations of IgG-specific anti-haemophilus influenzae type b, tetanus toxoid, and diphtheria toxoid were assayed in 6-month infant sera using ELISA methods. Multiple linear regression was used to estimate the relation between maternal, cord, and 6-month infant PCB concentrations and the antibody concentrations evaluated at 6-months of age. Results: Overall, there was little evidence of an association between infant antibody concentrations and PCB measures during the pre- and early postnatal period. In addition, our results did not show specificity in terms of associations limited to a particular developmental period (e.g. pre- vs. postnatal), a particular antibody, or a particular PCB congener. Conclusions: At the PCB concentrations measured in this cohort, which are high relative to most human populations today, we did not detect an association between maternal or early postnatal PCB exposure and specific antibody responses at 6-months of age.

  17. Effects of Aging on PuO2?xH2O Particle Size in Alkaline Solution

    SciTech Connect (OSTI)

    Delegard, Calvin H.

    2013-05-01

    Between 1944 and 1989, 54.5 metric tons of the United States weapons-grade plutonium and an additional 12.9 metric tons of fuel-grade plutonium were produced and separated from irradiated fuel at the Hanford Site. Acidic high-activity wastes containing around 600 kg of plutonium were made alkaline and discharged to underground storage tanks from separations, isolation, and recycle processes to yield average plutonium concentration of about 0.003 grams per liter (or ~0.0002 wt%) in the ~200 million liter tank waste volume. The plutonium is largely associated with low-solubility metal hydroxide/oxide sludges where its low concentration and intimate mixture with neutron-absorbing elements (e.g., iron) are credited in nuclear criticality safety. However, concerns have been expressed that plutonium, in the form of plutonium hydrous oxide, PuO2?xH2O, could undergo sufficient crystal growth through dissolution and reprecipitation in the alkaline tank waste to potentially become separable from neutron absorbing constituents by settling or sedimentation. Thermodynamic considerations and laboratory studies of systems chemically analogous to tank waste show that the plutonium formed in the alkaline tank waste by precipitation through neutralization from acid solution probably entered as 24-nm PuO2?xH2O crystallite particles that, because of their low solubility and opposition from radiolytic processes, grow from that point at exceedingly slow rates, thus posing no risk of physical segregation.

  18. Aging in the relaxor and ferroelectric state of Fe-doped (1-x)(Bi{sub 1/2}Na{sub 1/2})TiO₃-xBaTiO₃ piezoelectric ceramics

    SciTech Connect (OSTI)

    Sapper, Eva; Dittmer, Robert; Rödel, Jürgen; Damjanovic, Dragan; Erdem, Emre; Keeble, David J.; Jo, Wook; Granzow, Torsten

    2014-09-14

    Aging of piezoelectric properties was investigated in lead-free (1–x)(Bi{sub 1/2}Na{sub 1/2})TiO₃-xBaTiO₃ doped with 1at.% Fe. The relaxor character of the un-poled material prevents macroscopic aging effects, while in the field-induced ferroelectric phase aging phenomena are similar to those found in lead zirconate titanate or barium titanate. Most prominent aging effects are the development of an internal bias field and the decrease of switchable polarization. These effects are temperature activated, and can be explained in the framework of defect complex reorientation. This picture is further supported by electron paramagnetic resonance spectra indicating the existence of (Fe{sub Ti}´-V{sub O}{sup ••}){sup •} defect complexes in the Fe-doped material.

  19. Submerged Medium Voltage Cable Systems at Nuclear Power Plants. A Review of Research Efforts Relevant to Aging Mechanisms and Condition Monitoring

    SciTech Connect (OSTI)

    Brown, Jason; Bernstein, Robert; White, II, Gregory Von; Glover, Steven F.; Neely, Jason C.; Pena, Gary; Williamson, Kenneth Martin; Zutavern, Fred J.; Gelbard, Fred

    2015-03-01

    In a submerged environment, power cables may experience accelerated insulation degradation due to water - related aging mechanisms . Direct contact with water or moisture intrusion in the cable insulation s ystem has been identified in the literature as a significant aging stressor that can affect performance and lifetime of electric cables . Progressive reduction of the dielectric strength is commonly a result of water treeing which involves the development of permanent hydrophilic structures in the insulation coinciding with the absorption of water into the cable . Water treeing is a phenomenon in which dendritic microvoids are formed in electric cable insulation due to electrochemic al reactions , electromechanical forces , and diffusion of contaminants over time . These reactions are caused by the combined effect s of water presence and high electrical stress es in the material . Water tree growth follow s a tree - like branching pattern , i ncreasing in volume and length over time . Although these cables can be "dried out," water tree degradation , specifically the growth of hydrophilic regions, is believed to be permanent and typically worsens over time. Based on established research , water treeing or water induced damage can occur in a variety of electric cables including XLPE, TR - XLPE and other insulating materials, such as EPR and butyl rubber . Once water trees or water induced damage form, the dielectric strength of an insulation materia l will decrease gradually with time as the water trees grow in length, which could eventually result in failure of the insulating material . Under wet conditions or i n submerged environments , several environmental and operational parameters can influence w ater tree initiation and affect water tree growth . These parameters include voltage cycling, field frequency, temperature, ion concentration and chemistry, type of insula tion material , and the characteristics of its defects. In this effort, a review of academic and industrial literature was performed to identify : 1) findings regarding the degradation mechanisms of submerged cabling and 2) condition monitoring methods that may prove useful in predict ing the remaining lifetime of submerged medium voltage p ower cables . The re search was conducted by a multi - disciplinary team , and s ources includ ed official NRC reports, n ational l aboratory reports , IEEE standards, conference and journal proceedings , magazine articles , PhD dissertations , and discussions with experts . The purpose of this work was to establish the current state - of - the - art in material degradation modeling and cable condition monitoring techniques and to identify research gaps . Subsequently, future areas of focus are recommended to address these research gaps and thus strengthen the efficacy of the NRC's developing cable condition monitoring program . Results of this literature review and details of the test ing recommendations are presented in this report . FOREWORD To ensure the safe, re liable, and cost - effective long - term operation of nuclear power plants, many systems, structures, and components must be continuously evaluated. The Nuclear Regulatory Commission (NRC) has identified that cables in submerged environments are of concern, particularly as plants are seeking license renewal. To date, there is a lack of consensus on aging and degradation mechanisms even though the area of submerged cables has been extensively studied. Consequently, the ability to make lifetime predictions for submerged cable does not yet exist. The NRC has engaged Sandia National Laboratories (SNL) to lead a coordinated effort to help elucidate the aging and degradation of cables in submerged environments by collaborating with cable manufacturers, utilities, universities, and other government agencies. A team of SNL experts was assembled from the laboratories including electrical condition monitoring, mat erial science, polymer degradation, plasma physics, nuclear systems, and statistics. An objective of this research program is to perform a l iterature r eview to gather a body of knowledge on prior research projects, technical papers, and literature related to cable degradation in a submerged environment. In addition, the information gathered from the literature review will be employed to gain insights for developing an aging coefficient, and to determine which condition monitoring techniques are capable of tracking cable degradation in a submerged environment. Moreover, the information gathered from the l iterature r eview will also be used to determine which approach or approaches are best suited to develop test methods for accelerated aging and condition m onitoring of medium voltage cables. In summary of this initial effort, s ignificant work has been performed on submerged cable insulation degradation; however, there is a lack of uniform theories and acceptance of chemical and physical pathways. This lack of fundamental understanding is coupled with the inability to make predictive statements about material performance in wet or submerged environments. S elect condition monitoring methods known to the industry are discussed in this report and a dditional co ndition monitoring methods were added in this effort based on recommendations from the Nuclear Energy Standards Coordinating Collaborative and available literature. This NUREG review provides additional clarity on the use of condition monitoring methods t o detect water - related damage to medium voltage cable and new methods and approaches proposed in academia and industry. In order t o ensure continued improvement in the efficacy of a cable condition monitoring program, continued research and development (R&D) efforts are necessary. R&D efforts should complement operations, iteratively improving condition monitoring policies, procedures and outcomes. Ideally, field and laboratory data enable improved understanding of material science which in turn inform s the development of new or improved condition monitoring methods and lifetime models. Finally, these improved methods and models aid in the refinement of condition monitoring policies and procedures.

  20. 2009 Coal Age Buyers Guide

    SciTech Connect (OSTI)

    2009-07-15

    The buyers guide lists more than 1200 companies mainly based in the USA, that provide equipment and services to US coal mines and coal preparation plants. The guide is subdivided by product categories.

  1. Compare Activities by Building Age

    U.S. Energy Information Administration (EIA) Indexed Site

    4, 2009 2:52 PM http:www.eia.govconsumptioncommercialdataarchivecbecspba99compareage.html If you are having any technical problems with this site, please contact the EIA...

  2. Properties of aged metal tritides

    SciTech Connect (OSTI)

    McConville, G.T,; Menke, D.A.; West, D.S.; Woods, C.M.

    1994-06-22

    The interaction of tritium with metals is made complex by two phenomena. The first is that the beta decay in the metal produces {sup 3}He. The helium moves to form bubbles. This report shows that growth of the bubbles produces a two-stage swelling of the metal that comes first from the appearance of the helium and second from the relaxation of the lattice disorder. The second phenomena is the steady state ion and free radical concentration in the tritium over gas that interacts with impurities on the metal surface. This report shows that the reaction rates are much faster than for normal hydrogen cleaning.

  3. Coal Age buyers guide 2007

    SciTech Connect (OSTI)

    2007-07-15

    The buyers guide provides a comprehensive list of more than 1,200 suppliers that provide equipment and services to US coal mine and coal preparation plants, mainly based in the USA. Telephone numbers of companies are provided for each product category.

  4. Coal Age buyers guide 2005

    SciTech Connect (OSTI)

    2005-07-01

    The Buyers Guide provides a comprehensive list of more than 1,200 suppliers that provide equipment and services to US coal mine and coal preparation plants, mainly based in the USA. Telephone numbers of companies are provided for each product category.

  5. Coal Age buyers guide 2006

    SciTech Connect (OSTI)

    2006-07-15

    The Buyers Guide provides a comprehensive list of more than 1,200 suppliers that provide equipment and services to US coal mine and coal preparation plants, mainly based in the USA. Telephone numbers of companies are provided for each product category.

  6. Accelerated Aging of Roofing Surfaces

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... Sample 1: White Single-Ply Membrane, 5 Degree Tilt LBNL, Arizona LBNL, Florida LBNL, Ohio ... Budget History FY2010 FY2011 FY2012 DOE Cost-share DOE Cost-share DOE Cost-share 600K ...

  7. 2008 Coal Age buyers guide

    SciTech Connect (OSTI)

    2008-07-15

    The buyers guide lists more than 1200 companies mainly based in the USA, that provide equipment and services to US coal mines and coal preparation plants. The guide is subdivided by product categories.

  8. Thermal Release of 3He from Tritium Aged LaNi4.25Al0.75 Hydride

    SciTech Connect (OSTI)

    Staack, Gregory C.; Crowder, Mark L.; Klein, James E.

    2015-02-01

    Recently, the demand for He-3 has increased dramatically due to widespread use in nuclear nonproliferation, cryogenic, and medical applications. Essentially all of the world’s supply of He-3 is created by the radiolytic decay of tritium. The Savannah River Site Tritium Facilities (SRS-TF) utilizes LANA.75 in the tritium process to store hydrogen isotopes. The vast majority of He-3 “born” from tritium stored in LANA.75 is trapped in the hydride metal matrix. The SRS-TF has multiple LANA.75 tritium storage beds that have been retired from service with significant quantities of He-3 trapped in the metal. To support He-3 recovery, the Savannah River National Laboratory (SRNL) conducted thermogravimetric analysis coupled with mass spectrometry (TGA-MS) on a tritium aged LANA.75 sample. TGA-MS testing was performed in an argon environment. Prior to testing, the sample was isotopically exchanged with deuterium to reduce residual tritium and passivated with air to alleviate pyrophoric concerns associated with handling the material outside of an inert glovebox. Analyses indicated that gas release from this sample was bimodal, with peaks near 220 and 490°C. The first peak consisted of both He-3 and residual hydrogen isotopes, the second was primarily He-3. The bulk of the gas was released by 600 °C

  9. ALPHA SPECTROMETRIC EVALUATION OF SRM-995 AS A POTENTIAL URANIUM/THORIUM DOUBLE TRACER SYSTEM FOR AGE-DATING URANIUM MATERIALS

    SciTech Connect (OSTI)

    Beals, D.

    2011-12-06

    Uranium-233 (t{sub 1/2} {approx} 1.59E5 years) is an artificial, fissile isotope of uranium that has significant importance in nuclear forensics. The isotope provides a unique signature in determining the origin and provenance of uranium-bearing materials and is valuable as a mass spectrometric tracer. Alpha spectrometry was employed in the critical evaluation of a {sup 233}U standard reference material (SRM-995) as a dual tracer system based on the in-growth of {sup 229}Th (t{sub 1/2} {approx} 7.34E3 years) for {approx}35 years following radiochemical purification. Preliminary investigations focused on the isotopic analysis of standards and unmodified fractions of SRM-995; all samples were separated and purified using a multi-column anion-exchange scheme. The {sup 229}Th/{sup 233}U atom ratio for SRM-995 was found to be 1.598E-4 ({+-} 4.50%) using recovery-corrected radiochemical methods. Using the Bateman equations and relevant half-lives, this ratio reflects a material that was purified {approx} 36.8 years prior to this analysis. The calculated age is discussed in contrast with both the date of certification and the recorded date of last purification.

  10. Compliant alkali silicate sealing glass for solid oxide fuel cell applications: Combined stability in isothermal ageing and thermal cycling with YSZ coated ferritic stainless steels

    SciTech Connect (OSTI)

    Chou, Y. S.; Thomsen, Edwin C.; Choi, Jung-Pyung; Stevenson, Jeffry W.

    2012-01-01

    An alkali-containing silicate glass (SCN-1) is currently being evaluated as a candidate sealing glass for solid oxide fuel cell (SOFC) applications. The glass contains about 17 mole% alkalis (K+Na) and has low glass transition and softening temperatures. It remains vitreous and compliant around 750-800oC after sealing without substantial crystallization, as contrary to conventional glass-ceramic sealants, which experience rapid crystallization after the sealing process. The glassy nature and low characteristic temperatures can reduce residual stresses and result in the potential for crack healing. In a previous study, the glass was found to have good thermal cycle stability and was chemically compatible with YSZ coating during short term testing. In the current study, the compliant glass was further evaluated in a more realistic way in that the sealed glass couples were first isothermally aged for 1000h followed by thermal cycling. High temperature leakage was measured. The chemical compatibility was also investigated with powder mixtures at 700 and 800oC to enhance potential interfacial reaction. In addition, interfacial microstructure was examined with scanning electron microscopy and evaluated with regard to the leakage and chemical compatibility results.

  11. Effect of reinforcing particle type on morphology and age-hardening behavior of Al4.5 wt.% Cu based nanocomposites synthesized through mechanical milling

    SciTech Connect (OSTI)

    Mostaed, A.; Saghafian, H.; Mostaed, E.; Shokuhfar, A.; Rezaie, H.R.

    2013-02-15

    The effects of reinforcing particle type (SiC and TiC) on morphology and precipitation hardening behavior of Al4.5%Cu based nanocomposites synthesized via mechanical milling were investigated in the current work. In order to study the microstructure and morphology of mechanically milled powder, X-ray diffraction technique, scanning electron microscopy and high resolution transmission electron microscopy were utilized. Results revealed that at the early stages of mechanical milling, when reinforcing particles are polycrystal, the alloying process is enhanced more in the case of using the TiC particles as reinforcement. But, at the final stages of mechanical milling, when reinforcing particles are single crystal, the alloying process is enhanced more in the case of using the SiC ones. Transmission electron microscopy results demonstrated that Al4.5 wt.%Cu based nanocomposite powders were synthesized and confirmed that the mutual diffusion of aluminum and copper occurs through the interfacial plane of (200). The hardness results showed that not only does introducing 4 vol.% of reinforcing particles (SiC or TiC) considerably decrease the porosity of the bulk composite samples, but also it approximately doubles the hardness of Al4.5 wt.%Cu alloy (53.4 HB). Finally, apart from TEM and scanning electron microscopy observation which are localized, a decline in hardness in the TiC and SiC contained samples, respectively, after 1.5 and 2 h aging time at 473 K proves the fact that the size of SiC particles is smaller than the size of the TiC ones. - Highlights: ? HRTEM results show mutual diffusion of Al and Cu occurs through the (200) planes. ? TiC particles enhance alloying process more than the SiC ones at the early stages of MM. ? SiC particles enhance alloying process more than the TiC ones at the final stages of MM.

  12. THE MASS PROFILE AND SHAPE OF BARS IN THE SPITZER SURVEY OF STELLAR STRUCTURE IN GALAXIES (S{sup 4}G): SEARCH FOR AN AGE INDICATOR FOR BARS

    SciTech Connect (OSTI)

    Kim, Taehyun; Lee, Myung Gyoon; Sheth, Kartik; Muoz-Mateos, Juan-Carlos; Zaritsky, Dennis; Elmegreen, Bruce G.; Athanassoula, E.; Bosma, Albert; Holwerda, Benne; Ho, Luis C.; Comern, Sbastien; Laurikainen, Eija; Salo, Heikki; Knapen, Johan H.; Erroz-Ferrer, Santiago; Hinz, Joannah L.; Buta, Ronald J.; Kim, Minjin; Madore, Barry F.; and others

    2015-01-20

    We have measured the radial light profiles and global shapes of bars using two-dimensional 3.6 ?m image decompositions for 144 face-on barred galaxies from the Spitzer Survey of Stellar Structure in Galaxies. The bar surface brightness profile is correlated with the stellar mass and bulge-to-total (B/T) ratio of their host galaxies. Bars in massive and bulge-dominated galaxies (B/T> 0.2) show a flat profile, while bars in less massive, disk-dominated galaxies (B/T? 0) show an exponential, disk-like profile with a wider spread in the radial profile than in the bulge-dominated galaxies. The global two-dimensional shapes of bars, however, are rectangular/boxy, independent of the bulge or disk properties. We speculate that because bars are formed out of disks, bars initially have an exponential (disk-like) profile that evolves over time, trapping more disk stars to boxy bar orbits. This leads bars to become stronger and have flatter profiles. The narrow spread of bar radial profiles in more massive disks suggests that these bars formed earlier (z > 1), while the disk-like profiles and a larger spread in the radial profile in less massive systems imply a later and more gradual evolution, consistent with the cosmological evolution of bars inferred from observational studies. Therefore, we expect that the flatness of the bar profile can be used as a dynamical age indicator of the bar to measure the time elapsed since the bar formation. We argue that cosmic gas accretion is required to explain our results on bar profile and the presence of gas within the bar region.

  13. Phase transformation between Cu(In,Sn){sub 2} and Cu{sub 2}(In,Sn) compounds formed on single crystalline Cu substrate during solid state aging

    SciTech Connect (OSTI)

    Tian, Feifei; Liu, Zhi-Quan Guo, Jingdong

    2014-01-28

    Interfacial reactions between eutectic SnIn and single crystalline Cu during solid-state aging at low temperature were investigated systematically. Three types of phase transformations between Cu(In,Sn){sub 2} layer and Cu{sub 2}(In,Sn) layer were observed, which are Cu(In,Sn){sub 2} grows and Cu{sub 2}(In,Sn) consumes at 40?C, Cu(In,Sn){sub 2} and Cu{sub 2}(In,Sn) grow simultaneously at 60?C, as well as Cu(In,Sn){sub 2} consumes and Cu{sub 2}(In,Sn) grows at 80 and 100?C. According to physicochemical approach, the chemical reactions at Cu/Cu{sub 2}(In,Sn)/Cu(In,Sn){sub 2}/SnIn interfaces were discussed in detail. It was concluded that the diffusion ability of Cu and In atoms dominated different phase transformations. When diffusion constants k{sub 1In2}?>?8/3k{sub 1Cu2} Cu(In,Sn){sub 2} will grow, and if k{sub 1Cu2}???k{sub 1In2} Cu{sub 2}(In,Sn) will grow. Both Cu(In,Sn){sub 2} and Cu{sub 2}(In,Sn) can grow in the condition of k{sub 1In2} ? k{sub 1Cu2}. The values of k{sub 1Cu2} and k{sub 1In2} at different temperatures on (100)Cu and (111)Cu substrate were also calculated or estimated by analyzing the growth kinetics of the compound layers.

  14. Agent-based model forecasts aging of the population of people who inject drugs in metropolitan Chicago and changing prevalence of hepatitis C infections

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gutfraind, Alexander; Boodram, Basmattee; Prachand, Nikhil; Hailegiorgis, Atesmachew; Dahari, Harel; Major, Marian E.; Kaderali, Lars

    2015-09-30

    People who inject drugs (PWID) are at high risk for blood-borne pathogens transmitted during the sharing of contaminated injection equipment, particularly hepatitis C virus (HCV). HCV prevalence is influenced by a complex interplay of drug-use behaviors, social networks, and geography, as well as the availability of interventions, such as needle exchange programs. To adequately address this complexity in HCV epidemic forecasting, we have developed a computational model, the Agent-based Pathogen Kinetics model (APK). APK simulates the PWID population in metropolitan Chicago, including the social interactions that result in HCV infection. We used multiple empirical data sources on Chicago PWID tomore » build a spatial distribution of an in silico PWID population and modeled networks among the PWID by considering the geography of the city and its suburbs. APK was validated against 2012 empirical data (the latest available) and shown to agree with network and epidemiological surveys to within 1%. For the period 2010–2020, APK forecasts a decline in HCV prevalence of 0.8% per year from 44(±2)% to 36(±5)%, although some sub-populations would continue to have relatively high prevalence, including Non-Hispanic Blacks, 48(±5)%. The rate of decline will be lowest in Non-Hispanic Whites and we find, in a reversal of historical trends, that incidence among non-Hispanic Whites would exceed incidence among Non-Hispanic Blacks (0.66 per 100 per years vs 0.17 per 100 person years). APK also forecasts an increase in PWID mean age from 35(±1) to 40(±2) with a corresponding increase from 59(±2)% to 80(±6)% in the proportion of the population >30 years old. Our research highlight the importance of analyzing sub-populations in disease predictions, the utility of computer simulation for analyzing demographic and health trends among PWID and serve as a tool for guiding intervention and prevention strategies in Chicago, and other major cities.« less

  15. ON THE EXPANSION RATE, AGE, AND DISTANCE OF THE SUPERNOVA REMNANT G266.2–1.2 (Vela Jr.)

    SciTech Connect (OSTI)

    Allen, G. E.; Chow, K.; DeLaney, T.; Filipović, M. D.; Houck, J. C.; Pannuti, T. G.; Stage, M. D. E-mail: kc71135@gmail.com E-mail: m.filipovic@uws.edu.au E-mail: t.pannuti@moreheadstate.edu

    2015-01-10

    An analysis of Chandra ACIS data for two relatively bright and narrow portions of the northwestern rim of G266.2–1.2 (a.k.a. RX J0852.0-4622 or Vela Jr.) reveal evidence of a radial displacement of 2.40 ± 0.56 arcsec between 2003 and 2008. The corresponding expansion rate (0.42 ± 0.10 arcsec yr{sup –1} or 13.6% ± 4.2% kyr{sup –1}) is about half the rate reported for an analysis of XMM-Newton data from a similar, but not identical, portion of the rim over a similar, but not identical, time interval (0.84 ± 0.23 arcsec yr{sup –1}). If the Chandra rate is representative of the remnant as a whole, then the results of a hydrodynamic analysis suggest that G266.2–1.2 is between 2.4 and 5.1 kyr old if it is expanding into a uniform ambient medium (whether or not it was produced by a Type Ia or Type II event). If the remnant is expanding into the material shed by a steady stellar wind, then the age could be as much as 50% higher. The Chandra expansion rate and a requirement that the shock speed be greater than or equal to 1000 km s{sup –1} yields a lower limit on the distance of 0.5 kpc. An analysis of previously published distance estimates and constraints suggests G266.2–1.2 is no further than 1.0 kpc. This range of distances is consistent with the distance to the nearer of two groups of material in the Vela Molecular Ridge (0.7 ± 0.2 kpc) and to the Vel OB1 association (0.8 kpc)

  16. Agent-based model forecasts aging of the population of people who inject drugs in metropolitan Chicago and changing prevalence of hepatitis C infections

    SciTech Connect (OSTI)

    Gutfraind, Alexander; Boodram, Basmattee; Prachand, Nikhil; Hailegiorgis, Atesmachew; Dahari, Harel; Major, Marian E.; Kaderali, Lars

    2015-09-30

    People who inject drugs (PWID) are at high risk for blood-borne pathogens transmitted during the sharing of contaminated injection equipment, particularly hepatitis C virus (HCV). HCV prevalence is influenced by a complex interplay of drug-use behaviors, social networks, and geography, as well as the availability of interventions, such as needle exchange programs. To adequately address this complexity in HCV epidemic forecasting, we have developed a computational model, the Agent-based Pathogen Kinetics model (APK). APK simulates the PWID population in metropolitan Chicago, including the social interactions that result in HCV infection. We used multiple empirical data sources on Chicago PWID to build a spatial distribution of an in silico PWID population and modeled networks among the PWID by considering the geography of the city and its suburbs. APK was validated against 2012 empirical data (the latest available) and shown to agree with network and epidemiological surveys to within 1%. For the period 2010–2020, APK forecasts a decline in HCV prevalence of 0.8% per year from 44(±2)% to 36(±5)%, although some sub-populations would continue to have relatively high prevalence, including Non-Hispanic Blacks, 48(±5)%. The rate of decline will be lowest in Non-Hispanic Whites and we find, in a reversal of historical trends, that incidence among non-Hispanic Whites would exceed incidence among Non-Hispanic Blacks (0.66 per 100 per years vs 0.17 per 100 person years). APK also forecasts an increase in PWID mean age from 35(±1) to 40(±2) with a corresponding increase from 59(±2)% to 80(±6)% in the proportion of the population >30 years old. Our research highlight the importance of analyzing sub-populations in disease predictions, the utility of computer simulation for analyzing demographic and health trends among PWID and serve as a tool for guiding intervention and prevention strategies in Chicago, and other major cities.

  17. RECONNAISSANCE ASSESSMENT OF CO2 SEQUESTRATION POTENTIAL IN THE TRIASSIC AGE RIFT BASIN TREND OF SOUTH CAROLINA, GEORGIA, AND NORTHERN FLORIDA

    SciTech Connect (OSTI)

    Blount, G.; Millings, M.

    2011-08-01

    A reconnaissance assessment of the carbon dioxide (CO{sub 2}) sequestration potential within the Triassic age rift trend sediments of South Carolina, Georgia and the northern Florida Rift trend was performed for the Office of Fossil Energy, National Energy Technology Laboratory (NETL). This rift trend also extends into eastern Alabama, and has been termed the South Georgia Rift by previous authors, but is termed the South Carolina, Georgia, northern Florida, and eastern Alabama Rift (SGFAR) trend in this report to better describe the extent of the trend. The objectives of the study were to: (1) integrate all pertinent geologic information (literature reviews, drilling logs, seismic data, etc.) to create an understanding of the structural aspects of the basin trend (basin trend location and configuration, and the thickness of the sedimentary rock fill), (2) estimate the rough CO{sub 2} storage capacity (using conservative inputs), and (3) assess the general viability of the basins as sites of large-scale CO{sub 2} sequestration (determine if additional studies are appropriate). The CO{sub 2} estimates for the trend include South Carolina, Georgia, and northern Florida only. The study determined that the basins within the SGFAR trend have sufficient sedimentary fill to have a large potential storage capacity for CO{sub 2}. The deeper basins appear to have sedimentary fill of over 15,000 feet. Much of this fill is likely to be alluvial and fluvial sedimentary rock with higher porosity and permeability. This report estimates an order of magnitude potential capacity of approximately 137 billion metric tons for supercritical CO{sub 2}. The pore space within the basins represent hundreds of years of potential storage for supercritical CO{sub 2} and CO{sub 2} stored in aqueous form. There are many sources of CO{sub 2} within the region that could use the trend for geologic storage. Thirty one coal fired power plants are located within 100 miles of the deepest portions of these basins. There are also several cement and ammonia plants near the basins. Sixteen coal fired power plants are present on or adjacent to the basins which could support a low pipeline transportation cost. The current geological information is not sufficient to quantify specific storage reservoirs, seals, or traps. There is insufficient hydrogeologic information to quantify the saline nature of the water present within all of the basins. Water data in the Dunbarton Basin of the Savannah River Site indicates dissolved solids concentrations of greater than 10,000 parts per million (not potential drinking water). Additional reservoir characterization is needed to take advantage of the SGFAR trend for anthropogenic CO{sub 2} storage. The authors of this report believe it would be appropriate to study the reservoir potential in the deeper basins that are in close proximity to the current larger coal fired power plants (Albany-Arabi, Camilla-Ocilla, Alamo-Ehrhardt, and Jedburg basin).

  18. Synergistic Effect of High Charge and Energy Particle Radiation and Chronological Age on Biomarkers of Oxidative Stress and Tissue Degeneration: A Ground-Based Study Using the Vertebrate Laboratory Model Organism Oryzias latipes

    SciTech Connect (OSTI)

    Zheng, Xuan; Zhang, Xinyan; Ding, Lingling; Lee, Jeffrey R.; Weinberger, Paul M.; Dynan, William S.

    2014-11-06

    High charge and energy (HZE) particles are a main hazard of the space radiation environment. Uncertainty regarding their health effects is a limiting factor in the design of human exploration-class space missions, that is, missions beyond low earth orbit. Previous work has shown that HZE exposure increases cancer risk and elicits other aging-like phenomena in animal models. Here, we investigate how a single exposure to HZE particle radiation, early in life, influences the subsequent age-dependent evolution of oxidative stress and appearance of degenerative tissue changes. Embryos of the laboratory model organism, Oryzias latipes (Japanese medaka fish), were exposed to HZE particle radiation at doses overlapping the range of anticipated human exposure. A separate cohort was exposed to reference ?-radiation. Survival was monitored for 750 days, well beyond the median lifespan. The population was also sampled at intervals and liver tissue was subjected to histological and molecular analysis. HZE particle radiation dose and aging contributed synergistically to accumulation of lipid peroxidation products, which are a marker of chronic oxidative stress. This was mirrored by a decline in PPARGC1A mRNA, which encodes a transcriptional co-activator required for expression of oxidative stress defense genes and for mitochondrial maintenance. Consistent with chronic oxidative stress, mitochondria had an elongated and enlarged ultrastructure. Livers also had distinctive, cystic lesions. Depending on the endpoint, effects of ?-rays in the same dose range were either lesser or not detected. Results provide a quantitative and qualitative framework for understanding relative contributions of HZE particle radiation exposure and aging to chronic oxidative stress and tissue degeneration.

  19. Synergistic Effect of High Charge and Energy Particle Radiation and Chronological Age on Biomarkers of Oxidative Stress and Tissue Degeneration: A Ground-Based Study Using the Vertebrate Laboratory Model Organism Oryzias latipes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zheng, Xuan; Zhang, Xinyan; Ding, Lingling; Lee, Jeffrey R.; Weinberger, Paul M.; Dynan, William S.

    2014-11-06

    High charge and energy (HZE) particles are a main hazard of the space radiation environment. Uncertainty regarding their health effects is a limiting factor in the design of human exploration-class space missions, that is, missions beyond low earth orbit. Previous work has shown that HZE exposure increases cancer risk and elicits other aging-like phenomena in animal models. Here, we investigate how a single exposure to HZE particle radiation, early in life, influences the subsequent age-dependent evolution of oxidative stress and appearance of degenerative tissue changes. Embryos of the laboratory model organism, Oryzias latipes (Japanese medaka fish), were exposed to HZEmore » particle radiation at doses overlapping the range of anticipated human exposure. A separate cohort was exposed to reference γ-radiation. Survival was monitored for 750 days, well beyond the median lifespan. The population was also sampled at intervals and liver tissue was subjected to histological and molecular analysis. HZE particle radiation dose and aging contributed synergistically to accumulation of lipid peroxidation products, which are a marker of chronic oxidative stress. This was mirrored by a decline in PPARGC1A mRNA, which encodes a transcriptional co-activator required for expression of oxidative stress defense genes and for mitochondrial maintenance. Consistent with chronic oxidative stress, mitochondria had an elongated and enlarged ultrastructure. Livers also had distinctive, cystic lesions. Depending on the endpoint, effects of γ-rays in the same dose range were either lesser or not detected. Results provide a quantitative and qualitative framework for understanding relative contributions of HZE particle radiation exposure and aging to chronic oxidative stress and tissue degeneration.« less

  20. November 6, 2008; HSS/Union Working Group Meeting on Aging Workforce/Strategic Initiatives - DOE Illness and Injury Surveillance Program Worker Health Summary, 1995-2004

    Energy Savers [EERE]

    U.S. Department of Energy Illness and Injury Surveillance Program Worker Health Summary, 1995-2004 Questions or comments about this report or the Department of Energy's (DOE) Illness and Injury Surveillance Program (IISP) may be directed to: Dr. Cliff Strader at cliff.strader@hq.doe.gov or Dr. Bonnie Richter at bonnie.richter@hq.doe.gov United States Department of Energy Office of Health, Safety and Security Office of Illness and Injury Prevention Programs, HS-13 1000 Independence Avenue, SW

  1. Twenty-First Water Reactor Safety Information Meeting. Volume 3, Primary system integrity; Aging research, products and applications; Structural and seismic engineering; Seismology and geology: Proceedings

    SciTech Connect (OSTI)

    Monteleone, S.

    1994-04-01

    This three-volume report contains 90 papers out of the 102 that were presented at the Twenty-First Water Reactor Safety Information Meeting held at the Bethesda Marriott Hotel, Bethesda, Maryland, during the week of October 25-27, 1993. The papers are printed in the order of their presentation in each session and describe progress and results of programs in nuclear safety research conducted in this country and abroad. Foreign participation in the meeting included papers presented by researchers from France, Germany, Japan, Russia, Switzerland, Taiwan, and United Kingdom. The titles of the papers and the names of the authors have been updated and may differ from those that appeared in the final program of the meeting. Selected papers were indexed separately for inclusion in the Energy Science and Technology Database.

  2. Developing 226Ra and 227Ac age-dating techniques for nuclear forensics to gain insight from concordant and non-concordant radiochronometers

    SciTech Connect (OSTI)

    Kayzar, Theresa M.; Williams, Ross W.

    2015-09-26

    The model age or ‘date of purification’ of a nuclear material is an important nuclear forensic signature. In this study, chemical separation and MC-ICP-MS measurement techniques were developed for 226 Ra and 227Ac: grand-daughter nuclides in the 238U and 235U decay chains respectively. The 230Th-234U, 226Ra-238U, 231Pa-235U, and 227Ac-235U radiochronometers were used to calculate model ages for CRM-U100 standard reference material and two highly-enriched pieces of uranium metal from the International Technical Working Group Round Robin 3 Exercise. In conclusion, the results demonstrate the accuracy of the 226Ra-238U and 227Ac-235U chronometers and provide information about nuclide migration during uranium processing.

  3. VARIATION IN EROSION/DEPOSITION RATES OVER THE LAST FIFTTY YEARS ON ALLUVIAL FAN SURFACES OF L. PLEISTOCENE-MID HOLOCENE AGE, ESTIMATIONS USING 137CS SOIL PROFILE DATA, AMARGOSA VALLEY, NEVADA

    SciTech Connect (OSTI)

    C. Harrington; R. Kelly; K.T. Ebert

    2005-08-26

    Variations in erosion and deposition for the last fifty years (based on estimates from 137Cs profiles) on surfaces (Late Pleistocene to Late Holocene in age) making up the Fortymile Wash alluvial fan south of Yucca Mountain, is a function of surface age and of desert pavement development or absence. For purposes of comparing erosion and deposition, the surfaces can be examined as three groups: (1) Late Pleistocene surfaces possess areas of desert pavement development with thin Av or sandy A horizons, formed by the trapping capabilities of the pavements. These zones of deposition are complemented by coppice dune formation on similar parts of the surface. Areas on the surface where no pavement development has occurred are erosional in nature with 0.0 +/- 0.0 cm to 1.5 +/- 0.5 cm of erosion occurring primarily by winds blowing across the surface. Overall these surfaces may show either a small net depositional gain or small erosional loss. (2) Early Holocene surfaces have no well-developed desert pavements, but may have residual gravel deposits in small areas on the surfaces. These surfaces show the most consistent erosional surface areas on which it ranges from 1.0 +/-.01 cm to 2.0+/- .01 cm. Fewer depositional forms are found on this age of surface so there is probably a net loss of 1.5 cm across these surfaces. (3) The Late Holocene surfaces show the greatest variability in erosion and deposition. Overbank deposition during floods cover many edges of these surfaces and coppice dune formation also creates depositional features. Erosion rates are highly variable and range from 0.0 +/- 0.0 to a maximum of 2.0+/-.01. Erosion occurs because of the lack of protection of the surface. However, the common areas of deposition probably result in the surface having a small net depositional gain across these surfaces. Thus, the interchannel surfaces of the Fortymile Wash fan show a variety of erosional styles as well as areas of deposition. The fan, therefore, is a dynamic system that primarily responds to the incising of the channels into the upper fan surface, and the development of protecting desert pavements with time.

  4. High-Precision Plutonium Isotopic Compositions Measured on Los Alamos National Laboratory’s General’s Tanks Samples: Bearing on Model Ages, Reactor Modelling, and Sources of Material. Further Discussion of Chronometry

    SciTech Connect (OSTI)

    Spencer, Khalil J.; Rim, Jung Ho; Porterfield, Donivan R.; Roback, Robert Clifford; Boukhalfa, Hakim; Stanley, Floyd E.

    2015-06-29

    In this study, we re-analyzed late-1940’s, Manhattan Project era Plutonium-rich sludge samples recovered from the ''General’s Tanks'' located within the nation’s oldest Plutonium processing facility, Technical Area 21. These samples were initially characterized by lower accuracy, and lower precision mass spectrometric techniques. We report here information that was previously not discernable: the two tanks contain isotopically distinct Pu not only for the major (i.e., 240Pu, 239Pu) but trace (238Pu ,241Pu, 242Pu) isotopes. Revised isotopics slightly changed the calculated 241Am-241Pu model ages and interpretations.

  5. Initial Aging Studies of Unfilled VCE

    SciTech Connect (OSTI)

    Letant, S E; Herberg, J L; Wilson, T S; Alviso, C T; Chinn, S C; Maxwell, R S

    2008-10-09

    This report presents initial data on the effects of temperature, oxygen, and radiation on the chemical and structural properties of newly formulated, unfilled VCE. This initial effort focused on a pristine sample, and a replicate sample irradiated in air at a dose of 25MR. Thermal degradation was investigated by performing Thermogravimetric Analysis (TGA), and radiation-induced degradation was investigated using Differential Scanning Calorimetry (DSC), X-ray Diffraction (XRD), Solid Phase MicroExtraction--Gas Chromatography/Mass Spectrometry (SPME-GC/MS), as well as various Nuclear Magnetic Resonance (NMR) techniques including: {sup 13}C, {sup 13}C {sup 1}H cross polarization (CP), and {sup 1}H magic angle spinning (MAS) NMR.

  6. Aging Studies of Filled and Unfilled VCE

    SciTech Connect (OSTI)

    Letant, S; Herberg, J; Alviso, C; Small, W; Mulcahy, H; Pearson, M; Wilson, T; Chinn, S; Maxwell, R

    2009-11-10

    This report presents data on the effects of temperature and gamma radiation on the chemical and structural properties of both filled and unfilled VCE material produced by the Kansas City Plant using WR-qualified processes. Thermal effects up to 300 C and gamma irradiation doses of 1 MRad and 25 MRad were investigated under atmospheric conditions. Characterization techniques used in the study comprise Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), X-ray Diffraction (XRD), Tensile Testing, Solid Phase MicroExtraction - Gas Chromatography/Mass Spectrometry (SPME-GC/MS), phenol extraction followed by HPLC, and various Nuclear Magnetic Resonance (NMR) techniques including: {sup 13}C, {sup 13}C {l_brace}{sup 1}H{r_brace} cross polarization (CP), {sup 1}H magic angle spinning (MAS), 13C{l_brace}{sup 1}H{r_brace} Wide-line-Separation (2D-WISE) and development of Center band-Only Detection of Exchange (CODEX).

  7. Superconductivity at Dawn of the Iron Age

    ScienceCinema (OSTI)

    Tesanovic, Zlatko [Johns Hopkins University, Baltimore, Maryland, United States

    2010-09-01

    Superconductivity is a stunning quantum phenomenon and among the deepest paradigms in all of physics. From fundamental theories of the universe to strange goings-on in exotic materials to medical imaging and cell phones, its conceptual and practical dimensions span a reach as wide as anything in science. Twenty-odd years ago, the discovery of copper oxides ushered in a new era of high-temperature superconductivity, and the joyous exuberance that followed - with physicists throwing everything from fancy gauge theories to synchrotron radiation into its kitchen sink - only recently began to show any signs of waning. In the spring of 2008, as if on cue, a new family of iron pnictide high-temperature superconductors burst on the scene, hinting at an alternative route to room-temperature superconductivity and all of its momentous consequences. Fueled by genuine excitement - and a bit of hype - the iron-based superconductivity turned into a science blockbuster of 2009. I will present a pedagogical review of this new field, contrast the physics of iron- and copper-based systems, and speculate on the microscopic origins of the two types of high-temperature superconductivity.

  8. Little known heroes of the nuclear age

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    entire bodies. Two soldiers just outside the room, Pvt. John E. Tompkins and Pvt. John Hoffman, both Special Engineer Detachment soldiers, were also critically injured. Hoffman...

  9. Emerging NDE Technology for aging aircraft

    SciTech Connect (OSTI)

    Moore, D.G.; Perry, R.L.

    1998-03-01

    This paper presents an overview of several emerging nondestructive evaluation technologies that are being employed or considered for use to inspect commercial transport, commuter aircraft and military aircraft. An overview of the Federal Aviation Administration (FAA) Airworthiness Assurance NDI Validation Center (AANC) is described and how AANC teams with industry, universities, and other federal entities to assess these technologies.

  10. Documenting stone age cleverness by tool development

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Uto (National Institute of Advanced Industrial Science and technology, Japan), Megumi Kondo (Ochanomizu University, Japan), Masayuki Hyodo (Kobe University) and Gen Suwa...

  11. The Next ICE Age | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    Energy Hydro Research Foundation Fellows. | Image courtesy of the Hydro Research Foundation Fellowship Program. Hydro Research Foundation Fellows. | Image courtesy of the Hydro Research Foundation Fellowship Program. Michael Reed Michael Reed Director, Technical and Project Management Division As the nation continues to rely on hydropower to help meet its energy needs, a new generation of engineers and scientists is finding ways to make hydropower technologies more efficient,

  12. Organic Tanks Safety Program: Waste aging studies

    SciTech Connect (OSTI)

    Camaioni, D.M.; Samuels, W.D.; Lenihan, B.D.; Clauss, S.A.; Wahl, K.L.; Campbell, J.A.

    1994-11-01

    The underground storage tanks at the Hanford Complex contain wastes generated from many years of plutonium production and recovery processes, and mixed wastes from radiological degradation processes. The chemical changes of the organic materials used in the extraction processes have a direct on several specific safety issues, including potential energy releases from these tanks. This report details the first year`s findings of a study charged with determining how thermal and radiological processes may change the composition of organic compounds disposed to the tank. Their approach relies on literature precedent, experiments with simulated waste, and studies of model reactions. During the past year, efforts have focused on the global reaction kinetics of a simulated waste exposed to {gamma} radiation, the reactions of organic radicals with nitrite ion, and the decomposition reactions of nitro compounds. In experiments with an organic tank non-radioactive simulant, the authors found that gas production is predominantly radiolytically induced. Concurrent with gas generation they observe the disappearance of EDTA, TBP, DBP and hexone. In the absence of radiolysis, the TBP readily saponifies in the basic medium, but decomposition of the other compounds required radiolysis. Key organic intermediates in the model are C-N bonded compounds such as oximes. As discussed in the report, oximes and nitro compounds decompose in strong base to yield aldehydes, ketones and carboxylic acids (from nitriles). Certain aldehydes can react in the absence of radiolysis to form H{sub 2}. Thus, if the pathways are correct, then organic compounds reacting via these pathways are oxidizing to lower energy content. 75 refs.

  13. Multiscale Concrete Modeling of Aging Degradation

    SciTech Connect (OSTI)

    Hammi, Yousseff; Gullett, Philipp; Horstemeyer, Mark F.

    2015-07-31

    In this work a numerical finite element framework is implemented to enable the integration of coupled multiscale and multiphysics transport processes. A User Element subroutine (UEL) in Abaqus is used to simultaneously solve stress equilibrium, heat conduction, and multiple diffusion equations for 2D and 3D linear and quadratic elements. Transport processes in concrete structures and their degradation mechanisms are presented along with the discretization of the governing equations. The multiphysics modeling framework is theoretically extended to the linear elastic fracture mechanics (LEFM) by introducing the eXtended Finite Element Method (XFEM) and based on the XFEM user element implementation of Giner et al. [2009]. A damage model that takes into account the damage contribution from the different degradation mechanisms is theoretically developed. The total contribution of damage is forwarded to a Multi-Stage Fatigue (MSF) model to enable the assessment of the fatigue life and the deterioration of reinforced concrete structures in a nuclear power plant. Finally, two examples are presented to illustrate the developed multiphysics user element implementation and the XFEM implementation of Giner et al. [2009].

  14. Nuclear Deterrence in the Age of Nonproliferation

    SciTech Connect (OSTI)

    Richardson, J

    2009-01-21

    The fallacy of zero nuclear weapons, even as a virtual goal, is discussed. Because the complete abolition of nuclear weapons is not verifiable, nuclear weapons will always play a role in the calculus of assure, dissuade, deter and defeat (ADDD). However, the relative contribution of nuclear weapons to international security has diminished. To reconstitute the Cold War nuclear capability, with respect to both the nuclear weapons capability and their associated delivery systems, is fiscally daunting and not warranted due to competing budgetary pressures and their relative contribution to international security and nonproliferation. A proposed pathway to a sustainable nuclear weapons capability end-state is suggested which provides enough ADDD; a Dyad composed of fewer delivery and weapon systems, with trickle production at the National Laboratories and private sector to maintain capability and guard against technological surprise.

  15. 3D Printing Comes of Age

    Broader source: Energy.gov [DOE]

    The highlight of this year's International Manufacturing Technology Show (IMTS), held earlier in September at the McCormick Place Convention Center in Chicago, IL, was the electric car produced live during the Show. More than 110,000 people witnessed the representatives from Cincinnati Incorporated, Local Motors, and the Manufacturing Demonstration Facility at Oak Ridge National Laboratory in Tennessee print the working electric car layer by layer using carbon fiber reinforced polymer composite.

  16. NNSA Delivers All Scheduled W76-1 Units to Navy for 2012 | Y-12 National

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Security Complex Delivers All Scheduled ... NNSA Delivers All Scheduled W76-1 Units to Navy for 2012 Posted: November 19, 2012 - 2:28pm The National Nuclear Security Administration (NNSA) today announced that it delivered all of its scheduled W76-1 Submarine Launched Ballistic Missile warhead units to United States Navy in FY 2012. "As our stockpile ages, we have to put ourselves in a position where the president can be certain that it is safe, secure and effective," said NNSA

  17. DISCOVERY OF A FAINT X-RAY COUNTERPART AND A PARSEC-LONG X-RAY TAIL FOR THE MIDDLE-AGED, {gamma}-RAY-ONLY PULSAR PSR J0357+3205

    SciTech Connect (OSTI)

    De Luca, A.; Bignami, G. F.; Marelli, M.; Caraveo, P. A.; Mignani, R. P.; Hummel, W.; Collins, S.; Shearer, A.; Parkinson, P. M. Saz; Belfiore, A.

    2011-06-01

    The Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope opened a new era for pulsar astronomy, detecting {gamma}-ray pulsations from more than 60 pulsars, {approx}40% of which are not seen at radio wavelengths. One of the most interesting sources discovered by LAT is PSR J0357+3205, a radio-quiet, middle-aged ({tau}{sub C} {approx} 0.5 Myr) pulsar standing out for its very low spin-down luminosity (E-dot{sub rot}{approx}6x10{sup 33} erg s{sup -1}), indeed the lowest among non-recycled {gamma}-ray pulsars. A deep X-ray observation with Chandra (0.5-10 keV), coupled with sensitive optical/infrared ground-based images of the field, allowed us to identify PSR J0357+3205 as a faint source with a soft spectrum, consistent with a purely non-thermal emission (photon index {Gamma} = 2.53 {+-} 0.25). The absorbing column (N{sub H} = 8 {+-} 4 x 10{sup 20} cm{sup -2}) is consistent with a distance of a few hundred parsecs. Moreover, the Chandra data unveiled a huge (9 arcmin long) extended feature apparently protruding from the pulsar. Its non-thermal X-ray spectrum points to synchrotron emission from energetic particles from the pulsar wind, possibly similar to other elongated X-ray tails associated with rotation-powered pulsars and explained as bow-shock pulsar wind nebulae (PWNe). However, energetic arguments as well as the peculiar morphology of the diffuse feature associated with PSR J0357+3205 make the bow-shock PWN interpretation rather challenging.

  18. A Hydrostratigraphic Model and Alternatives for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 97: Yucca Flat-Climax Mine, Lincoln and Nye Counties, Nevada

    SciTech Connect (OSTI)

    Geotechnical Sciences Group Bechtel Nevada

    2006-01-01

    A new three-dimensional hydrostratigraphic framework model for the Yucca Flat-Climax Mine Corrective Action Unit was completed in 2005. The model area includes Yucca Flat and Climax Mine, former nuclear testing areas at the Nevada Test Site, and proximal areas. The model area is approximately 1,250 square kilometers in size and is geologically complex. Yucca Flat is a topographically closed basin typical of many valleys in the Basin and Range province. Faulted and tilted blocks of Tertiary-age volcanic rocks and underlying Proterozoic and Paleozoic sedimentary rocks form low ranges around the structural basin. During the Cretaceous Period a granitic intrusive was emplaced at the north end of Yucca Flat. A diverse set of geological and geophysical data collected over the past 50 years was used to develop a structural model and hydrostratigraphic system for the basin. These were integrated using EarthVision? software to develop the 3-dimensional hydrostratigraphic framework model. Fifty-six stratigraphic units in the model area were grouped into 25 hydrostratigraphic units based on each unit's propensity toward aquifer or aquitard characteristics. The authors organized the alluvial section into 3 hydrostratigraphic units including 2 aquifers and 1 confining unit. The volcanic units in the model area are organized into 13 hydrostratigraphic units that include 8 aquifers and 5 confining units. The underlying pre-Tertiary rocks are divided into 7 hydrostratigraphic units, including 3 aquifers and 4 confining units. Other units include 1 Tertiary-age sedimentary confining unit and 1 Mesozoic-age granitic confining unit. The model depicts the thickness, extent, and geometric relationships of these hydrostratigraphic units (''layers'' in the model) along with the major structural features (i.e., faults). The model incorporates 178 high-angle normal faults of Tertiary age and 2 low-angle thrust faults of Mesozoic age. The complexity of the model area and the non-uniqueness of some of the interpretations incorporated into the base model made it necessary to formulate alternative interpretations for some of the major features in the model. Five of these alternatives were developed so they could be modeled in the same fashion as the base model. This work was done for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of the Underground Test Area subproject of the Environmental Restoration Project.

  19. United States

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    l 0 United States Office of Research and Environmental Protection Agency Development Washington, DC 20460 EPA 600/R-94/209 January 1993 Offsite Environment itoring Report adiation Monitoring Around United States Nuclear Test Areas, Calendar Year 1992 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY OFFICE OF RESEARCH AND DEVELOPMENT ENVIRONMENTAL MONITORING SYSTEMS LABORATORY-LAS VEGAS P.O. BOX 93478 LAS VEGAS, NEVADA 89193-3478 , 702/798-2100 April 20, 1995 Dear Reader: Since 1954, the U.S.

  20. United States

    Office of Legacy Management (LM)

    - I United States Department of Energy D lSCk Al M E R "This book was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe

  1. Using physiologically based pharmacokinetic modeling to address nonlinear kinetics and changes in rodent physiology and metabolism due to aging and adaptation in deriving reference values for propylene glycol methyl ether and propylene glycol methyl ether acetate.

    SciTech Connect (OSTI)

    Kirman, C R.; Sweeney, Lisa M.; Corley, Rick A.; Gargas, M L.

    2005-04-01

    Reference values, including an oral reference dose (RfD) and an inhalation reference concentration (RfC), were derived for propylene glycol methyl ether (PGME), and an oral RfD was derived for its acetate (PGMEA). These values were based upon transient sedation observed in F344 rats and B6C3F1 mice during a two-year inhalation study. The dose-response relationship for sedation was characterized using internal dose measures as predicted by a physiologically based pharmacokinetic (PBPK) model for PGME and its acetate. PBPK modeling was used to account for changes in rodent physiology and metabolism due to aging and adaptation, based on data collected during weeks 1, 2, 26, 52, and 78 of a chronic inhalation study. The peak concentration of PGME in richly perfused tissues was selected as the most appropriate internal dose measure based upon a consideration of the mode of action for sedation and similarities in tissue partitioning between brain and other richly perfused tissues. Internal doses (peak tissue concentrations of PGME) were designated as either no-observed-adverse-effect levels (NOAELs) or lowest-observed-adverse-effect levels (LOAELs) based upon the presence or absence of sedation at each time-point, species, and sex in the two year study. Distributions of the NOAEL and LOAEL values expressed in terms of internal dose were characterized using an arithmetic mean and standard deviation, with the mean internal NOAEL serving as the basis for the reference values, which was then divided by appropriate uncertainty factors. Where data were permitting, chemical-specific adjustment factors were derived to replace default uncertainty factor values of ten. Nonlinear kinetics are were predicted by the model in all species at PGME concentrations exceeding 100 ppm, which complicates interspecies and low-dose extrapolations. To address this complication, reference values were derived using two approaches which differ with respect to the order in which these extrapolations were performed: (1) uncertainty factor application followed by interspecies extrapolation (PBPK modeling); and (2) interspecies extrapolation followed by uncertainty factor application. The resulting reference values for these two approaches are substantially different, with values from the former approach being 7-fold higher than those from the latter approach. Such a striking difference between the two approaches reveals an underlying issue that has received little attention in the literature regarding the application of uncertainty factors and interspecies extrapolations to compounds where saturable kinetics occur in the range of the NOAEL. Until such discussions have taken place, reference values based on the latter approach are recommended for risk assessments involving human exposures to PGME and PGMEA.

  2. Deactivation of Accelerated Engine-Aged and Field-Aged SCR Catalysts...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    More Documents & Publications Impact of Biodiesel-Based Na on the Selective Catalytic Reduction (SCR) of NOx Using Cu-zeolite Impacts of Biodiesel on Emission Control Devices ...

  3. United States

    Office of Legacy Management (LM)

    onp5fGonal Ruord United States of America . I. .' - PROCEEDINGS AND DEBATES OF THE 9t?lh CONGRESS, FIRST SESSION United States Government Printing Office SUPERINTENDENT OF DOCUMENTS Wash!ogtm. 0.C 20402 OFFICIAL BUSINESS Penalty for pwate use. sco Congressmal Record (USPS 087-390) Postage and Fees Pad I.) s ~lJ"er"ment Prlntlng OffIce 375 SECOND CLASS NEWSPAPER -...~-- -~- -- --- H 45' 78 ' cCJ~GRESSIONAL RECORD - HOUSE June 28, 1983 H.J. Res. 213: Mr. BOLAND, Mr. WAXM.UG Mr. OBERSTAR.

  4. United States

    Office of Legacy Management (LM)

    onSres;eional atecord United States of America :- PROCEEDINGS AND DEBATES OF THE 981h CONGRESS, FIRST SESSION United States Government Printing Office SUPERINTENDENT OF DOCUMENTS Washwtn. D C 20402 OFFICIAL BUSINESS Penalty for plvate use. $300 Congressmnal Record (USPS 087-390) Postage and Fees Pad U S Government Prtnttng Offlce 375 SECOND CLASS NEWSPAPER H 45' 78 * C.QvGRESSIONAL RECORD - HOUSE .-. June 28, 1983 H.J. Res. 273: Mr. BOLAND. Mr. Whxrdhr?. Mr. OBERsThx. Mi. BEDELL, Mr. BONER of

  5. " Million Housing Units, Final...

    U.S. Energy Information Administration (EIA) Indexed Site

    Final" ,,"Housing Unit Type" ,,"Single-Family Units",,"Apartments in Buildings With" ... ,,"RSEs for Housing Unit Type" ,,"Single-Family Units",,"Apartments in Buildings With" ...

  6. United States

    Energy Savers [EERE]

    Tenaslta Power Services Co. OE Docket No. EA-243-A Order Authorizing Electricity Exports to Canada Order No. EA-243-A March 1,2007 Tenaska Power Services Co. Order No. EA-243-A I. BACKGROUND Exports of elcctricity from the United States to a foreign country are regulated by the Department of Energy (DOE) pursuant to sections 30 I(b) and 402(f) of the Departrncnt of' Energy Organizatio~l Act (42 U, S.C. 7 15 1 (b), 7 1 72Cf)) and rcquirc authorization under section 202(e) of the Federal Power Act

  7. United States

    Energy Savers [EERE]

    BP Energy Company OE Docket No. EA- 3 14 Order Authorizing Electricity Exports to Mexico Order No. EA-3 14 February 22,2007 BP Energy Company Order No. EA-314 I. BACKGROUND Exports of electricity from the United States to a foreign country are regulated by the Department of Energy (DOE) pursuant to sections 301(b) and 402(Q of the Department of Energy Organization Act (42 U.S.C. 7 15 l(b), 7172(f)) and require authorization under section 202(e) of the Federal Power Act (FPA) (16 U.S.C.S24a(e)) .

  8. UNITED STEELWORKERS

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    FOIARequestNovember 13, 2015 UNITED STEELWORKERS " ' " ' " USW Local 12-369 797 Stevens Drive Richland, Washington 99352 --P-hone-509-7-1-3-~J.180-or-FA-X:-509-71-3-1-783- - - * - - - UNRY AND $JIU!N$'!'H FQ.11; wc:HU<Elt5 November 13, 2015 USW-DLR-015-075 Dorothy Riehle, FOIA Officer Depa.rtment of Energy Richland Operations (RL) and (ORP) P.O. Box 550, Mail Stop A7-75 . Richland, WA 99352 SUBJECT: FREEDOM OF INFORMATION ACT AND/OR PRIVACY ACT REQUEST Dear Ms. Riehle: I am

  9. Termination unit

    DOE Patents [OSTI]

    Traeholt, Chresten [Frederiksberg, DK; Willen, Dag [Klagshamn, SE; Roden, Mark [Newnan, GA; Tolbert, Jerry C [Carrollton, GA; Lindsay, David [Carrollton, GA; Fisher, Paul W [Heiskell, TN; Nielsen, Carsten Thidemann [Jaegerspris, DK

    2014-01-07

    This invention relates to a termination unit comprising an end-section of a cable. The end section of the cable defines a central longitudinal axis and comprising end-parts of N electrical phases, an end-part of a neutral conductor and a surrounding thermally insulation envelope adapted to comprising a cooling fluid. The end-parts of the N electrical phases and the end-part of the neutral conductor each comprising at least one electrical conductor and being arranged in the cable concentrically around a core former with a phase 1 located relatively innermost, and phase N relatively outermost in the cable, phase N being surrounded by the neutral conductor, electrical insulation being arrange between neighboring electrical phases and between phase N and the neutral conductor, and wherein the end-parts of the neutral conductor and the electrical phases each comprise a contacting surface electrically connected to at least one branch current lead to provide an electrical connection: The contacting surfaces each having a longitudinal extension, and being located sequentially along the longitudinal extension of the end-section of the cable. The branch current leads being individually insulated from said thermally insulation envelope by individual electrical insulators.

  10. Increasing the resilience and security of the United States' power infrastructure

    SciTech Connect (OSTI)

    Happenny, Sean F.

    2015-08-01

    The United States' power infrastructure is aging, underfunded, and vulnerable to cyber attack. Emerging smart grid technologies may take some of the burden off of existing systems and make the grid as a whole more efficient, reliable, and secure. The Pacific Northwest National Laboratory (PNNL) is funding research into several aspects of smart grid technology and grid security, creating a software simulation tool that will allow researchers to test power infrastructure control and distribution paradigms by utilizing different smart grid technologies to determine how the grid and these technologies react under different circumstances. Understanding how these systems behave in real-world conditions will lead to new ways to make our power infrastructure more resilient and secure. Demonstrating security in embedded systems is another research area PNNL is tackling. Many of the systems controlling the U.S. critical infrastructure, such as the power grid, lack integrated security and the aging networks protecting them are becoming easier to attack.

  11. SEPA United States Environmental Monitoring EPA/600/4-861022

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ... In addition, physical examinations of the off-site residents revealed a normally healthy population consonant with the age and sex distribution of .that population. Community ...

  12. UNITED STATES OF AMERICA DEPARTMENT OF ENERGY OFFICE OF FOSSIL...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    premature death, heart failure, chronic respiratory damage, and premature aging of the lungs. Sierra Club states that significant ozone pollution also damages plants and...

  13. Securing the United States' power infrastructure

    SciTech Connect (OSTI)

    Happenny, Sean F.

    2015-08-01

    The United States’ power infrastructure is aging, underfunded, and vulnerable to cyber attack. Emerging smart grid technologies may take some of the burden off of existing systems and make the grid as a whole more efficient, reliable, and secure. The Pacific Northwest National Laboratory (PNNL) is funding research into several aspects of smart grid technology and grid security, creating a software simulation tool that will allow researchers to test power distribution networks utilizing different smart grid technologies to determine how the grid and these technologies react under different circumstances. Demonstrating security in embedded systems is another research area PNNL is tackling. Many of the systems controlling the U.S. critical infrastructure, such as the power grid, lack integrated security and the networks protecting them are becoming easier to breach. Providing a virtual power substation network to each student team at the National Collegiate Cyber Defense Competition, thereby supporting the education of future cyber security professionals, is another way PNNL is helping to strengthen the security of the nation’s power infrastructure.

  14. Age of the Coso Formation Inyo County California | Open Energy...

    Open Energy Info (EERE)

    the Coso indicates that the Coso Formation contains strata at least as old as 6.0 m.y. (million years) and no younger than 2.5 m.y. Within the Coso Formation, Blancan fossils...

  15. Enzyme Structure Provides Insights into Cancer and Aging

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    protein are responsible for three different human diseases: in xeroderma pigmentosum (XP), extreme sensitivity to sunlight promotes cancer; Cockayne syndrome (CS) involves...

  16. Aging and Embrittlement of High Fluence Stainless Steels

    SciTech Connect (OSTI)

    Was, gary; Jiao, Zhijie; der ven, Anton Van; Bruemmer, Stephen; Edwards, Dan

    2012-12-31

    Irradiation of austenitic stainless steels results in the formation of dislocation loops, stacking fault tetrahedral, Ni-Si clusters and radiation-induced segregation (RIS). Of these features, it is the formation of precipitates which is most likely to impact the mechanical integrity at high dose. Unlike dislocation loops and RIS, precipitates exhibit an incubation period that can extend from 10 to 46 dpa, above which the cluster composition changes and a separate phase, (G-phase) forms. Both neutron and heavy ion irradiation showed that these clusters develop slowly and continue to evolve beyond 100 dpa. Overall, this work shows that the irradiated microstructure features produced by heavy ion irradiation are remarkably comparable in nature to those produced by neutron irradiation at much lower dose rates. The use of a temperature shift to account for the higher damage rate in heavy ion irradiation results in a fairly good match in the dislocation loop microstructure and the precipitate microstructure in austenitic stainless steels. Both irradiations also show segregation of the same elements and in the same directions, but to achieve comparable magnitudes, heavy ion irradiation must be conducted at a much higher temperature than that which produces a match with loops and precipitates. First-principles modeling has confirmed that the formation of Ni-Si precipitates under irradiation is likely caused by supersaturation of solute to defect sinks caused by highly correlated diffusion of Ni and Si. Thus, the formation and evolution of Ni-Si precipitates at high dose in austenitic stainless steels containing Si is inevitable.

  17. Rapid Aging Protocols for Diesel Aftertreatment Devices: NOx Abatement Catalysts

    Broader source: Energy.gov [DOE]

    Poster presentation at the 2007 Diesel Engine-Efficiency & Emissions Research Conference (DEER 2007). 13-16 August, 2007, Detroit, Michigan. Sponsored by the U.S. Department of Energy's (DOE) Office of FreedomCAR and Vehicle Technologies (OFCVT).

  18. Catching the entrepreneurial spirit at a young age

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Mockingbird Books. "Our mission is to create a comfortable, welcoming and inclusive environment for people who want and love to read," the young team wrote. "We will have...

  19. Emissions trading comes of age as a strategic tool

    SciTech Connect (OSTI)

    Pospisil, R.

    1996-03-01

    Trading of emissions credits has quickly evolved from a curiosity to a viable compliance strategy for electric utilities and power-generating industrial firms. A sure sign that emissions trading has matured is the entry of power marketers onto the scene; in bundling pollution allowances with their electricity offerings, they are making their product more attractive - and stealing a page from the coal companies` strategy book to boot. Although most current activity involves credits for sulfur dioxide (SO{sub 2}), nitrogen oxide (NO{sub x}) trading is under way in certain areas as well, although NO{sub x} markets are local and thus slower to develop. However, utilities see economic development potential in this area; some are providing NO{sub x} credits to their industrial customers to help them comply with environmental regulations - and to retain their loyalty when deregulation affords them a choice of electricity suppliers. This paper briefly discusses the issues related to emissions trading.

  20. Space-Age Ceramics Get Their Toughest Test

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    applied loads (10, 127, and 98 newtons, respectively). *Load reading after first matrix crack initiated. The results provide vital information about the underlying failure...