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Sample records for doe sodium bearing

  1. Steam Reforming Application for Treatment of DOE Sodium Bearing Tank Wastes at INL for ICP

    SciTech Connect

    J. Bradley Mason; Kevin Ryan; Scott Roesener; Michael Cowen; Duane Schmoker; Pat Bacala; Bill Landman

    2006-03-01

    The patented THOR® steam reforming waste treatment technology has been selected as the technology of choice for treatment of Sodium Bearing Waste (SBW) at the Idaho National Laboratory (INL) for the Idaho Cleanup Project (ICP). SBW is an acidic tank waste at the Idaho Nuclear Technology and Engineering Center (INTEC) at INL. It consists primarily of waste from decontamination activities and laboratory wastes. SBW contains high concentrations of nitric acid, alkali and aluminum nitrates, with minor amounts of many inorganic compounds including radionuclides, mainly cesium and strontium. The THOR® steam reforming process will convert the SBW tank waste feed into a dry, solid, granular product. The THOR® technology was selected to treat SBW, in part, because it can provide flexible disposal options to accommodate the final disposition path selected for SBW. THOR® can produce a final end-product that will meet anticipated requirements for disposal as Remote-Handled TRU (RH-TRU) waste; and, with modifications, THOR® can also produce a final endproduct that could be qualified for disposal as High Level Waste (HLW). SBW treatment will be take place within the Integrated Waste Treatment Unit (IWTU), a new facility that will be located at the INTEC. This paper provides an overview of the THOR® process chemistry and process equipment being designed for the IWTU.

  2. Steam Reforming Application for Treatment of DOE Sodium Bearing Tank Wastes at Idaho National Laboratory for Idaho Cleanup Project

    SciTech Connect

    Landman, W.; Roesener, S.; Mason, B.; Wolf, K.; Amaria, N.

    2007-07-01

    The patented THOR{sup R} steam reforming waste treatment technology has been selected by the Department of Energy (DOE) as the technology of choice for treatment of about one million gallons of Sodium Bearing Waste (SBW) at the Idaho National Laboratory (INL). SBW is an acidic waste created primarily from cleanup of the fuel reprocessing equipment at the Idaho Nuclear Technology and Engineering Center (INTEC) at the INL. SBW contains high concentrations of nitric acid and alkali and aluminum nitrates with minor amounts of many inorganic compounds including radionuclides, mainly cesium. The steam reforming process will convert the SBW into dry, solid, carbonate and aluminate minerals supporting a preferred path for disposal as remote handled transuranic (RH-TRU) waste at the Waste Isolation Pilot Project (WIPP). The Idaho Cleanup Project (ICP) will design, build, and operate an Integrated Waste Treatment Unit (IWTU) that will comprise an integrated THOR{sup R} process system that will utilize dual fluidized bed steam reformers (FBSR) for treatment of the SBW. Design of the IWTU is nearing completion. The IWTU will be constructed at INTEC, immediately east of the New Waste Calcine Facility (NWCF), with planned fabrication and construction to start in early 2007 upon receipt of needed permits and completion of design and engineering. This paper provides a project and process overview of the IWTU and discusses the design and construction status. IWTU equipment and facility designs and bases will be presented. (authors)

  3. Steam Reforming Technology Demonstration Program for Treatment of DOE Sodium Bearing Tank Wastes at Idaho National Laboratory

    SciTech Connect

    Ryan, K.; Mason, B.; Wolf, K.; Olson, A.

    2007-07-01

    The patented THOR{sup R} steam reforming waste treatment technology has been selected by the Department of Energy (DOE) for treatment of Sodium Bearing Waste (SBW) at the Idaho National Laboratory (INL). SBW is an acidic waste created primarily from cleanup of the fuel reprocessing equipment at the Idaho Nuclear Technology and Engineering Center (INTEC) at the INL. The SBW contains high concentrations of nitric acid and alkali and aluminum nitrates, along with many other inorganic compounds, including substantial levels of radionuclides. As part of the implementation of the THOR{sup R} process at INTEC, an engineering-scale test demonstration (ESTD) was conducted using a specially designed pilot plant located at Hazen Research, Inc. in Golden Colorado. The purpose of the ESTD was to confirm and optimize operation of the THOR{sup R} dual fluidized bed steam reforming (FBSR) process for treating the SBW. The performance of the integrated FBSR thermal and off-gas systems was demonstrated while treating waste simulants representative of the actual SBW. Simulants were utilized that consisted of highly acidic nitrate solutions, with both dissolved and undissolved solids (UDS). The SBW simulant solutions were converted into a dry, granular solid, consisting of carbonate and aluminate product compounds. The successful performance of the integrated FBSR system was verified and demonstrated. (authors)

  4. Steam Reforming Application for Treatment of DOE Sodium Bearing Tank Wastes at Idaho National Laboratory for Idaho Cleanup Project

    SciTech Connect

    Mason, J.B.; Wolf, K.; Ryan, K.; Roesener, S.; Cowen, M.; Schmoker, D.; Bacala, P.; Landman, B.

    2006-07-01

    The patented THOR{sup R} steam reforming waste treatment technology has been selected as the technology of choice for treatment of Sodium Bearing Waste (SBW) at the Idaho National Laboratory (INL) for the Idaho Cleanup Project (ICP). SBW is an acidic tank waste at the Idaho Nuclear Technology and Engineering Center (INTEC) at INL. It consists primarily of waste from decontamination activities and laboratory wastes. SBW contains high concentrations of nitric acid, alkali and aluminum nitrates, with minor amounts of many inorganic compounds including radionuclides, mainly cesium and strontium. The THOR{sup R} steam reforming process will convert the SBW tank waste feed into a dry, solid, granular product. The THOR{sup R} technology was selected to treat SBW, in part, because it can provide flexible disposal options to accommodate the final disposition path selected for SBW. THOR{sup R} can produce a final end-product that will meet anticipated requirements for disposal as Remote-Handled TRU (RH-TRU) waste; and, with modifications, THOR{sup R} can also produce a final end-product that could be qualified for disposal as High Level Waste (HLW). SBW treatment will be take place within the Integrated Waste Treatment Unit (IWTU), a new facility that will be located at the INTEC. This paper provides an overview of the THOR{sup R} process chemistry and process equipment being designed for the IWTU. (authors)

  5. Sodium Bearing Waste Processing Alternatives Analysis

    SciTech Connect

    Murphy, James Anthony; Palmer, Brent J; Perry, Keith Joseph

    2003-12-01

    A multidisciplinary team gathered to develop a BBWI recommendation to DOE-ID on the processing alternatives for the sodium bearing waste in the INTEC Tank Farm. Numerous alternatives were analyzed using a rigorous, systematic approach. The data gathered were evaluated through internal and external peer reviews for consistency and validity. Three alternatives were identified to be top performers: Risk-based Calcination, MACT to WIPP Calcination and Cesium Ion Exchange. A dual-path through early Conceptual design is recommended for MACT to WIPP Calcination and Cesium Ion Exchange since Risk-based Calcination does not require design. If calcination alternatives are not considered based on giving Type of Processing criteria significantly greater weight, the CsIX/TRUEX alternative follows CsIX in ranking. However, since CsIX/TRUEX shares common uncertainties with CsIX, reasonable backups, which follow in ranking, are the TRUEX and UNEX alternatives. Key uncertainties must be evaluated by the decision-makers to choose one final alternative. Those key uncertainties and a path forward for the technology roadmapping of these alternatives is provided.

  6. Steam Reforming Technology Demonstration for Conversion of DOE Sodium-Bearing Tank Wastes at Idaho National Laboratory into a Leach-Resistant Alkali Aluminosilicate Waste Form

    SciTech Connect

    Ryan, K.; Bradley Mason, J.; Evans, B.; Vora, V.; Olson, A.

    2008-07-01

    The patented THOR{sup R} fluidized-bed steam reforming (FBSR) technology was selected by the U.S. Department of Energy (DOE) for treatment of sodium-bearing waste (SBW) in the Integrated Waste Treatment Unit (IWTU), currently under construction at the Idaho National Laboratory (INL) Site.1 SBW is an acidic waste created primarily from cleanup of the fuel reprocessing equipment at the Idaho Nuclear Technology and Engineering Center (INTEC) at the INL. The SBW contains high concentrations of nitric acid, and alkali and aluminum nitrates, along with many other inorganic compounds, including substantial levels of radionuclides. As part of the implementation of the THOR{sup R} process at INTEC, an engineering-scale technology demonstration (ESTD) was conducted using a specially designed pilot plant located at Hazen Research, Inc. in Golden Colorado. This ESTD confirmed the efficacy of the THOR{sup R} FBSR process to convert the SBW into a granular carbonate-based waste form suitable for disposal at the Waste Isolation Pilot Plant (WIPP). DOE authorized, as a risk reduction measure, the performance of an additional ESTD to demonstrate the production of an insoluble mineralized product, in the event that an alternate disposition path is required. The additional ESTD was conducted at the Hazen Research facility using the THOR{sup R} process and the same SBW simulant employed previously. An alkali aluminosilicate mineral product was produced that exhibited excellent leach resistance and chemical durability. The demonstration established general system operating parameters for a full-scale facility; provided process off-gas data that confirmed operation within regulatory limits; determined that the mineralized product exhibits superior leach resistance and durability, compared to Environmental Assessment (EA) and Low-activity Reference Material (LRM) glasses, as indicated by the Product Consistency Test (PCT); ascertained that Cs and Re (a surrogate for Tc) were non

  7. Sodium-Bearing Waste Treatment Alternatives Implementation Study

    SciTech Connect

    Charles M. Barnes; James B. Bosley; Clifford W. Olsen

    2004-07-01

    The purpose of this document is to discuss issues related to the implementation of each of the five down-selected INEEL/INTEC radioactive liquid waste (sodium-bearing waste - SBW) treatment alternatives and summarize information in three main areas of concern: process/technical, environmental permitting, and schedule. Major implementation options for each treatment alternative are also identified and briefly discussed. This report may touch upon, but purposely does not address in detail, issues that are programmatic in nature. Examples of these include how the SBW will be classified with respect to the Nuclear Waste Policy Act (NWPA), status of Waste Isolation Pilot Plant (WIPP) permits and waste storage availability, available funding for implementation, stakeholder issues, and State of Idaho Settlement Agreement milestones. It is assumed in this report that the SBW would be classified as a transuranic (TRU) waste suitable for disposal at WIPP, located in New Mexico, after appropriate treatment to meet transportation requirements and waste acceptance criteria (WAC).

  8. Sodium-bearing Waste Treatment Technology Evaluation Report

    SciTech Connect

    Charles M. Barnes; Arlin L. Olson; Dean D. Taylor

    2004-05-01

    Sodium-bearing waste (SBW) disposition is one of the U.S. Department of Energy (DOE) Idaho Operation Office’s (NE-ID) and State of Idaho’s top priorities at the Idaho National Engineering and Environmental Laboratory (INEEL). The INEEL has been working over the past several years to identify a treatment technology that meets NE-ID and regulatory treatment requirements, including consideration of stakeholder input. Many studies, including the High-Level Waste and Facilities Disposition Environmental Impact Statement (EIS), have resulted in the identification of five treatment alternatives that form a short list of perhaps the most appropriate technologies for the DOE to select from. The alternatives are (a) calcination with maximum achievable control technology (MACT) upgrade, (b) steam reforming, (c) cesium ion exchange (CsIX) with immobilization, (d) direct evaporation, and (e) vitrification. Each alternative has undergone some degree of applied technical development and preliminary process design over the past four years. This report presents a summary of the applied technology and process design activities performed through February 2004. The SBW issue and the five alternatives are described in Sections 2 and 3, respectively. Details of preliminary process design activities for three of the alternatives (steam reforming, CsIX, and direct evaporation) are presented in three appendices. A recent feasibility study provides the details for calcination. There have been no recent activities performed with regard to vitrification; that section summarizes and references previous work.

  9. Idaho Nuclear Technology and Engineering Center (INTEC) Sodium Bearing Waste - Waste Incidental to Reprocessing Determination

    SciTech Connect

    Jacobson, Victor Levon

    2002-08-01

    U.S. Department of Energy Manual 435.1-1, Radioactive Waste Management, Section I.1.C, requires that all radioactive waste subject to Department of Energy Order 435.1 be managed as high-level radioactive waste, transuranic waste, or low-level radioactive waste. Determining the radiological classification of the sodium-bearing waste currently in the Idaho Nuclear Technology and Engineering Center Tank Farm Facility inventory is important to its proper treatment and disposition. This report presents the technical basis for making the determination that the sodium-bearing waste is waste incidental to spent fuel reprocessing and should be managed as mixed transuranic waste. This report focuses on the radiological characteristics of the sodiumbearing waste. The report does not address characterization of the nonradiological, hazardous constituents of the waste in accordance with Resource Conservation and Recovery Act requirements.

  10. Feed Composition for Sodium-Bearing Waste Treatment Process

    SciTech Connect

    Barnes, C.M.

    2000-10-30

    Treatment of sodium-bearing waste (SBW) at the Idaho Nuclear Technology and Engineering Center (INTEC) within the Idaho National Engineering and Environmental Laboratory is mandated by a Settlement Agreement between the Department of Energy and the State of Idaho. One of the requirements of the Settlement Agreement is to complete treatment of SBW by December 31, 2012. To support both design and development studies for the SBW treatment process, detailed feed compositions are needed. This report contains the expected compositions of these feed streams and the sources and methods used in obtaining these compositions.

  11. Adsorption of sodium lauryl sulfate onto arsenic-bearing ferrihydrite.

    PubMed

    Quan, C; Khoe, G; Bagster, D

    2001-02-01

    Ferrihydrite is an excellent adsorbent for binding trace toxic contaminants such as arsenic, and precipitate flotation of the arsenic-bearing ferrihydrite has been studied. Anionic surfactants such as sodium lauryl sulfate (SLS) and sodium oleate (NaOL) are suitable collectors for the flotation. The adsorption of SLS both alone and after the subsequent addition of NaOL on these precipitates at pH 4-5 was measured. It has been shown that the synergistic effect of the two surfactants on flotation is dependent on their addition order. The presence of NaOL before SLS in the conditioning stage can prevent the adsorption of SLS because of the electrostatic shielding of adsorption sites on the precipitates. The post addition of NaOL to the SLS-bearing precipitates can promote the flocculation of the precipitates and enhance entrainment of SLS for better flotation. The SLS adsorption data fit better with the modified Frumkin isotherm than the Langmuir isotherm. Thermodynamic parameters (-delta Gads0,delta Hads0, and delta Sads0) have been derived from the analysis of the adsorption isotherms. The results suggest that the adsorption of SLS on AFH is physical and exothermic. PMID:11229002

  12. Feasibility Study for Vitrification of Sodium-Bearing Waste

    SciTech Connect

    J. J. Quigley; B. D. Raivo; S. O. Bates; S. M. Berry; D. N. Nishioka; P. J. Bunnell

    2000-09-01

    Treatment of sodium-bearing waste (SBW) at the Idaho Nuclear Technology and Engineering Center (INTEC) within the Idaho National Engineering and Environmental Laboratory is mandated under a Settlement Agreement between the Department of Energy and the State of Idaho. One of the requirements of the Settlement Agreement is the complete calcination (i.e., treatment) of all SBW by December 31, 2012. One of the proposed options for treatment of SBW is vitrification. This study will examine the viability of SBW vitrification. This study describes the process and facilities to treat the SBW, from beginning waste input from INTEC Tank Farm to the final waste forms. Schedules and cost estimates for construction and operation of a Vitrification Facility are included. The study includes a facility layout with drawings, process description and flow diagrams, and preliminary equipment requirements and layouts.

  13. Glass Formulation Development for INEEL Sodium-Bearing Waste

    SciTech Connect

    Vienna, John D.; Buchmiller, William C.; Crum, Jarrod V.; Graham, Dennis D.; Kim, Dong-Sang; Macisaac, Brett D.; Schweiger, Michael J.; Peeler, David K.; Edwards, Tommy B.; Reamer, Irene A.; Workman, R. J.

    2002-08-01

    Studies were performed to develop and test a glass formulation for immobilization of sodium-bearing waste (SBW). SBW is a high soda, acid high activity waste stored at the INEEL in 10 underground tanks. It was determined in previous studies that SBW?s sulfur content dictates the its loading in borosilicate glasses to be melted by currently assumed processes. If the sulfur content (which is ~4.5 mass% SO3 on a non-volatile oxide basis in SBW) of the melter feed is too high then a molten alkali sulfate containing salt phase accumulates on the melt surface. The avoidance of salt accumulation during the melter process and the maximization of sulfur incorporation into the glass melt were the main focus of this development work. A glass was developed for 20 mass% SBW (on a non-volatile oxide basis), which contained 0.91 mass% SO3, that met all the processing and product quality constraint determined for SBW vitrification at a planned INEEL treatment plant?SBW-22-20. This report summarizes the formulation efforts and presents the data developed on a series of glasses with simulated SBW. Summary

  14. Pre-Decisional Sodium Bearing Waste Technology Development Roadmap FY-01 Update

    SciTech Connect

    Mc Dannel, Gary Eidson

    2001-09-01

    This report provides an update to the Sodium Bearing Waste (SBW) Technology Development Roadmap generated a year ago. It outlines progress made to date and near-term plans for the technology development work necessary to support processing SBW. In addition, it serves as a transition document to the Risk Management Plan (RMP) required by the Project per DOE Order 413.3, “Program and Project Management for the Acquisition of Capital Assets.” Technical uncertainties have been identified as design basis elements (DBEs) and captured in a technical baseline database. As the risks are discovered, assessed, and mitigated, the status of the DBEs in the database will be updated and tracked to closure.

  15. Glass Formulation Development for INEEL Sodium-Bearing Waste

    SciTech Connect

    J.D. Vienna; M.J. Schweiger; D.E. Smith; H.D. Smith; J.V. Crum; D.K. Peeler; I.A. Reamer; C.A. Musick; R.D. Tillotson

    1999-08-03

    For about four decades, radioactive wastes have been collected and calcined from nuclear fuels reprocessing at the Idaho Nuclear Technology and Engineering Center (INTEC), formerly Idaho Chemical Processing Plant (ICPP). Over this time span, secondary radioactive wastes have also been collected and stored as liquid from decontamination, laboratory activities, and fuel-storage activities. These liquid wastes are collectively called sodium-bearing wastes (SBW). About 5.7 million liters of these wastes are temporarily stored in stainless steel tanks at the Idaho National Engineering and Environmental Laboratory (INEEL). Vitrification is being considered as an immobilization step for SBW with a number of treatment and disposal options. A systematic study was undertaken to develop a glass composition to demonstrate direct vitrification of INEEL's SBW. The objectives of this study were to show the feasibility of SBW vitrification, not a development of an optimum formulation. The waste composition is relatively high in sodium, aluminum, and sulfur. A specific composition and glass property restrictions, discussed in Section 2, were used as a basis for the development. Calculations based on first-order expansions of selected glass properties in composition and some general tenets of glass chemistry led to an additive (fit) composition (68.69 mass % SiO{sub 2}, 14.26 mass% B{sub 2}O{sub 3}, 11.31 mass% Fe{sub 2}O{sub 3}, 3.08 mass% TiO{sub 2}, and 2.67 mass % Li{sub 2}O) that meets all property restrictions when melted with 35 mass % of SBW on an oxide basis, The glass was prepared using oxides, carbonates, and boric acid and tested to confirm the acceptability of its properties. Glass was then made using waste simulant at three facilities, and limited testing was performed to test and optimize processing-related properties and confirm results of glass property testing. The measured glass properties are given in Section 4. The viscosity at 1150 C, 5 Pa{center_dot}s, is

  16. Test Summary Report INEEL Sodium-Bearing Waste Vitrification Demonstration RSM-01-1

    SciTech Connect

    Goles, Ronald W.; Perez, Joseph M.; Macisaac, Brett D.; Siemer, Darryl D.; Mccray, John A.

    2001-05-21

    The U.S. Department of Energy's Idaho National Engineering and Environmental Laboratory is storing large amounts of radioactive and mixed wastes. Most of the sodium-bearing wastes have been calcined, but about a million gallons remain uncalcined, and this waste does not meet current regulatory requirements for long-term storage and/or disposal. As a part of the Settlement Agreement between DOE and the State of Idaho, the tanks currently containing SBW are to be taken out of service by December 31, 2012, which requires removing and treatment the remaining SBW. Vitrification is the option for waste disposal that received the highest weighted score against the criteria used. Beginning in FY 2000, the INEEL high-level waste program embarked on a program for technology demonstration and development that would lead to conceptual design of a vitrification facility in the event that vitrification is the preferred alternative for SBW disposal. The Pacific Northwest National Laborator's Research-Scale Melter was used to conduct these initial melter-flowsheet evaluations. Efforts are underway to reduce the volume of waste vitrified, and during the current test, an overall SBW waste volume-reduction factor of 7.6 was achieved.

  17. Review of FY2001 Development Work for Vitrification of Sodium Bearing Waste

    SciTech Connect

    Barnes, C.M.; Taylor, D.D.

    2002-09-09

    Treatment of sodium-bearing waste (SBW) at the Idaho Nuclear Technology and Engineering Center (INTEC) within the Idaho National Engineering and Environmental Laboratory is mandated by the Settlement Agreement between the Department of Energy and the State of Idaho. This report discusses significant findings from vitrification technology development during 2001 and their impacts on the design basis for SBW vitrification.

  18. Review of FY 2001 Development Work for Vitrification of Sodium Bearing Waste

    SciTech Connect

    Taylor, Dean Dalton; Barnes, Charles Marshall

    2002-09-01

    Treatment of sodium-bearing waste (SBW) at the Idaho Nuclear Technology and Engineering Center (INTEC) within the Idaho National Engineering and Environmental Laboratory is mandated by the Settlement Agreement between the Department of Energy and the State of Idaho. This report discusses significant findings from vitrification technology development during 2001 and their impacts on the design basis for SBW vitrification.

  19. Preparation and characterization of sodium bearing perovskite phases

    SciTech Connect

    Kulkarni, N.K. Sali, S.K.; Mudher, K.D. Singh; Venugopal, V.

    2008-02-05

    Ceramic waste-forms constitute a major alternative to glass for immobilization of radionuclides in solid phase, with advantage of greater stability in the presence of water at moderate temperature. CaZrO{sub 3} and SrZrO{sub 3} with ABO{sub 3} perovskite structure are suitable host matrices for fixation of sodium and neodymium. Three new phases with compositions Na{sub 0.5}Nd{sub 0.5}ZrO{sub 3}, Ca{sub 0.44}Na{sub 0.28}Nd{sub 0.28}ZrO{sub 3} and Sr{sub 0.6}Na{sub 0.2}Nd{sub 0.2}ZrO{sub 3} have been synthesized and characterized as orthorhombic phases. The crystal structure of Ca{sub 0.44}Na{sub 0.28}Nd{sub 0.28}ZrO{sub 3} was derived from the crystallographic parameters of CaZrO{sub 3} using X-ray powder diffraction data in the orthorhombic system by Rietveld profile method. Preliminary leaching studies carried out in a digestion bomb showed low leachability of sodium and neodymium in water at 70 deg. C from Ca{sub 0.44}Na{sub 0.28}Nd{sub 0.28}ZrO{sub 3} matrix as compared to that from Sr{sub 0.6}Na{sub 0.2}Nd{sub 0.2}ZrO{sub 3} matrix.

  20. Idaho Nuclear Technology and Engineering Center Sodium-Bearing Waste Treatment Research and Development FY-2002 Status Report

    SciTech Connect

    Herbst, Alan Keith; Deldebbio, John Anthony; Mc Cray, John Alan; Kirkham, Robert John; Olson, Lonnie Gene; Scholes, Bradley Adams

    2002-09-01

    The Idaho National Engineering and Environmental Laboratory (INEEL) is considering several optional processes for disposal of liquid sodium-bearing waste. During fiscal year 2002, immobilization-related research included of grout formulation development for sodium-bearing waste, absorption of the waste on silica gel, and off-gas system mercury collection and breakthrough using activated carbon. Experimental results indicate that sodium-bearing waste can be immobilized in grout at 70 weight percent and onto silica gel at 74 weight percent. Furthermore, a loading of 11 weight percent mercury in sulfur-impregnated activated carbon was achieved with 99.8% off-gas mercury removal efficiency.

  1. Alternative TRUEX-Based Pretreatment Processing of INEEL Sodium Bearing Waste

    SciTech Connect

    Rapko, Brian M.; Fiskum, Sandra K.; Lumetta, Gregg J.

    2000-09-27

    The goals of this study were to demonstrate a selective complexant for separating mercury from the transuranic (TRU) elements in the transuranic extraction (TRUEX) process and to demonstrate alternative stripping methods to eliminate phosphorus-containing, actinide stripping agents during TRUEX processing. The work described in this report provides the basis for implementing an improved TRUEX-based flowsheet for processing INEEL sodium-bearing waste using only minor modifications to the current Idaho National Engineering and Environmental Laboratory (INEEL) flowsheet design.

  2. Leaching of vanadium, sodium, and silicon from molten V-Ti-bearing slag obtained from low-grade vanadium-bearing titanomagnetite

    NASA Astrophysics Data System (ADS)

    Zhu, Yuan-yuan; Yi, Ling-yun; Zhao, Wei; Chen, De-sheng; Zhao, Hong-xin; Qi, Tao

    2016-08-01

    The water leaching process of vanadium, sodium, and silicon from molten vanadium-titanium-bearing (V-Ti-bearing) slag obtained from low-grade vanadium-bearing titanomagnetite was investigated systematically. The results show that calcium titanate, sodium aluminosilicate, sodium oxide, silicon dioxide and sodium vanadate are the major components of the molten V-Ti-bearing slag. The experimental results indicate that the liquid-solid (L/S) mass ratio significantly affects the leaching process because of the respective solubilities and diffusion rates of the components. A total of 83.8% of vanadium, 72.8% of sodium, and 16.1% of silicon can be leached out via a triple counter-current leaching process under the optimal conditions of a particle size below 0.074 mm, a temperature of 90°C, a leaching time of 20 min, an L/S mass ratio of 4:1, and a stirring speed of 300 r/min. The kinetics of vanadium leaching is well described by an internal diffusion-controlled model and the apparent activation energy is 11.1 kJ/mol. The leaching mechanism of vanadium was also analyzed.

  3. Feed Composition for Sodium-Bearing Waste Treatment Process, Rev. 3

    SciTech Connect

    Barnes, Charles Marshall

    2003-09-01

    Treatment of sodium-bearing waste (SBW) at the Idaho Nuclear Technology and Engineering Center (INTEC) within the Idaho National Engineering and Environmental Laboratory is mandated by a Settlement Agreement between the Department of Energy and the State of Idaho. One of the requirements of the Settlement Agreement is to complete treatment of SBW by December 31, 2012. To support both design and development studies for the SBW treatment process, detailed feed compositions are needed. This report contains the expected compositions of these feed streams and the sources and methods used in obtaining these compositions.

  4. Phase 2 THOR Steam Reforming Tests for Sodium Bearing Waste Treatment

    SciTech Connect

    Nicholas R. Soelberg

    2004-01-01

    About one million gallons of acidic, hazardous, and radioactive sodium-bearing waste is stored in stainless steel tanks at the Idaho Nuclear Technology and Engineering Center (INTEC), which is a major operating facility of the Idaho National Engineering and Environmental Laboratory. Steam reforming is a candidate technology being investigated for converting the waste into a road ready waste form that can be shipped to the Waste Isolation Pilot Plant in New Mexico for interment. A steam reforming technology patented by Studsvik, Inc., and licensed to THOR Treatment Technologies has been tested in two phases using a Department of Energy-owned fluidized bed test system located at the Science Applications International Corporation (SAIC) Science and Technology Applications Research Center located in Idaho Falls, Idaho. The Phase 1 tests were reported earlier in 2003. The Phase 2 tests are reported here. For Phase 2, the process feed rate, stoichiometry, and chemistry were varied to identify and demonstrate process operation and product characteristics under different operating conditions. Two test series were performed. During the first series, the process chemistry was designed to produce a sodium carbonate product. The second series was designed to produce a more leach-resistant, mineralized sodium aluminosilicate product. The tests also demonstrated the performance of a MACT-compliant off-gas system.

  5. Suitability of Silica Gel to Process INEEL Sodium Bearing Waste - Letter Report

    SciTech Connect

    Kirkham, Robert John; Herbst, Alan Keith

    2000-09-01

    The suitability of using the silica gel process for Idaho National Engineering and Environmental Laboratory (INEEL) sodium bearing waste was investigated during fiscal year 2000. The study was co-funded by the Tanks Focus Area as part of TTP No. ID-77WT-31 and the High Level Waste Program. The task also included the investigation of possible other absorbents. Scoping tests and examination of past work showed that the silica gel absorption/adsorption and drying method was the most promising; thus only silica gel was studied and not other absorbents. The documentation on the Russian silica gel process provided much of the needed information but did not provide some of the processing detail so these facts had to be inferred or gleaned from the literature.

  6. Modeling of NOx Destruction Options for INEEL Sodium-Bearing Waste Vitrification

    SciTech Connect

    Wood, Richard Arthur

    2001-09-01

    Off-gas NOx concentrations in the range of 1-5 mol% are expected as a result of the proposed vitrification of sodium-bearing waste at the Idaho National Engineering and Environmental Laboratory. An existing kinetic model for staged combustion (originally developed for NOx abatement from the calcination process) was updated for application to vitrification offgas. In addition, two new kinetic models were developed to assess the feasibility of using selective non-catalytic reduction (SNCR) or high-temperature alone for NOx abatement. Each of the models was developed using the Chemkin code. Results indicate that SNCR is a viable option, reducing NOx levels to below 1000 ppmv. In addition, SNCR may be capable of simultaneously reducing CO emissions to below 100 ppmv. Results for using high-temperature alone were not as promising, indicating that a minimum NOx concentration of 3950 ppmv is achievable at 3344°F.

  7. Process Options Description for Vitrification Flowsheet Model of INEEL Sodium Bearing Waste

    SciTech Connect

    Nichols, Todd Travis; Taylor, Dean Dalton; Lauerhass, Lance; Barnes, Charles Marshall

    2001-02-01

    The purpose of this document is to provide the technical information to Savannah River Site (SRS) personnel that is required for the development of a basic steady-state process simulation of the vitrification treatment train of sodium bearing waste (SBW) at Idaho National Engineering and nvironmental Laboratory (INEEL). INEEL considers simulation to have an important role in the integration/optimization of treatment process trains for the High Level Waste (HLW) Program. This project involves a joint Technical Task Plan (TTP ID77WT31, Subtask C) between SRS and INEEL. The work scope of simulation is different at the two sites. This document addresses only the treatment of SBW at INEEL. The simulation model(s) is to be built by SRS for INEEL in FY-2001.

  8. Glass Formulation Development for INEEL Sodium -Bearing Waste (FY2001 WM-180)

    SciTech Connect

    Peeler, D.K.

    2001-09-21

    A systematic study was undertaken to develop a glass composition to demonstrate the vitrification flowsheet of the Idaho National Engineering and Environmental Laboratory's sodium bearing waste (SBW) using the latest WM-180 tank composition. Although the previous study did not restrict waste loadings (WLs) based on the potential to form a segregated salt layer, avoiding its development in a melter is beneficial and was the primary focus from the glass-formulation perspective. The testing results described in this report were aimed at providing a candidate glass composition for use in a scaled melter demonstration of direct vitrification of WM-180 in the Research Scale Melter (RSM) at Pacific Northwest National Laboratory and the EV-16 melter at the Clemson Environmental Technology Laboratory.

  9. Na3Ti2(PO4)(3) as a sodium-bearing anode for rechargeable aqueous sodium-ion batteries

    SciTech Connect

    Li, Z; Ravnsbaek, DB; Xiang, K; Chiang, YM

    2014-07-01

    Na3Ti2(PO4)(3) synthesized as fine carbon-coated powders is demonstrated for the first time to be a suitable sodium-bearing anode material for rechargeable aqueous sodium-ion batteries (ANaBs). Importantly, Na3Ti2(PO4)(3) is found to be stable in deoxygenated water, enabling use of this material in aqueous systems. As a sodiated anode, it allows use of sodium-depleted cathode materials that require supply of sodium-ions from the anode. As an example, we demonstrate for the first time the use of olivine FePO4 as a cathode in an ANaB. (C) 2014 Elsevier B.V. All rights reserved.

  10. Does despotic behavior or food search explain the occurrence of problem brown bears in Europe?

    PubMed Central

    Elfström, Marcus; Zedrosser, Andreas; Jerina, Klemen; Støen, Ole-Gunnar; Kindberg, Jonas; Budic, Lara; Jonozovič, Marko; Swenson, Jon E

    2014-01-01

    Bears foraging near human developments are often presumed to be responding to food shortage, but this explanation ignores social factors, in particular despotism in bears. We analyzed the age distribution and body condition index (BCI) of shot brown bears in relation to densities of bears and people, and whether the shot bears were killed by managers (i.e., problem bears; n = 149), in self-defense (n = 51), or were hunter-killed nonproblem bears (n = 1,896) during 1990–2010. We compared patterns between areas with (Slovenia) and without supplemental feeding (Sweden) of bears relative to 2 hypotheses. The food-search/food-competition hypothesis predicts that problem bears should have a higher BCI (e.g., exploiting easily accessible and/or nutritious human-derived foods) or lower BCI (e.g., because of food shortage) than nonproblem bears, that BCI and human density should have a positive correlation, and problem bear occurrence and seasonal mean BCI of nonproblem bears should have a negative correlation (i.e., more problem bears during years of low food availability). Food competition among bears additionally predicts an inverse relationship between BCI and bear density. The safety-search/naivety hypothesis (i.e., avoiding other bears or lack of human experience) predicts no relationship between BCI and human density, provided no dietary differences due to spatiotemporal habitat use among bears, no relationship between problem bear occurrence and seasonal mean BCI of nonproblem bears, and does not necessarily predict a difference between BCI for problem/nonproblem bears. If food competition or predation avoidance explained bear occurrence near settlements, we predicted younger problem than nonproblem bears and a negative correlation between age and human density. However, if only food search explained bear occurrence near settlements, we predicted no relation between age and problem or nonproblem bear status, or between age and human density. We found

  11. Paramont's Black Bear No. 4 mine does it right, again

    SciTech Connect

    Sanda, A.

    2007-07-15

    The Paramont Coal Company Virginia, LLC, a subsidiary of Alpha Natural Resources, recently won the '2007 overall award for excellence in mining and reclamation from the Virginia Division of Mined Land Reclamation and the Virginia Mining Association. Coal People Magazine recently visited Black Bear No. 4 mine where a settling pond was being removed and stream bed placed to drain the area, part of the 451-acre award winning reclamation project. The article recounts discussions with mining engineers about the company's operations with emphasis on the Black Bear No. 4 mine. Black Bear No. 1 mine won five state and national awards last year for conservation and land management practices. 8 photos.

  12. Spatial distribution of interstellar dust in the Sun's vicinity. Comparison with neutral sodium-bearing gas

    NASA Astrophysics Data System (ADS)

    Vergely, J.-L.; Valette, B.; Lallement, R.; Raimond, S.

    2010-07-01

    Aims: 3D tomography of the interstellar dust and gas may be useful in many respects, from the physical and chemical evolution of the interstellar medium itself to foreground decontamination of the cosmic microwave background, or various studies of the environments of specific objects. However, while spectral data cubes of the galactic emission become increasingly precise, the information on the distance to the emitting regions has not progressed as well and relies essentially on the galactic rotation curve. Our goal here is to bring more precise information on the distance to nearby interstellar dust and gas clouds within 250 pc. Methods: We apply the best available calibration methods to a carefully screened set of stellar Strömgren photometry data for targets possessing a Hipparcos parallax and spectral type classification. We combine the derived interstellar extinctions and the parallax distances for about 6000 stars to build a 3D tomography of the local dust. We use an inversion method based on a regularized Bayesian approach and a least squares criterion, optimized for this specific data set. We apply the same inversion technique to a totally independent set of neutral sodium absorption data available for about 1700 target stars. Results: We obtain 3D maps of the opacity and the distance to the main dust-bearing clouds within 250 pc and identify in those maps well-known dark clouds and high galactic more diffuse entities. We calculate the integrated extinction between the Sun and the cube boundary and compare this with the total galactic extinction derived from infrared 2D maps. The two quantities reach similar values at high latitudes, as expected if the local dust content is satisfyingly reproduced and the dust is closer than 250 pc. Those maps show a larger high latitude dust opacity in the North compared to the South, reinforcing earlier evidences. Interestingly the gas maps do not show the same asymmetry, suggesting a polar asymmetry of the dust to gas

  13. Phase 2 TWR Steam Reforming Test for Sodium-Bearing Waste Treatment

    SciTech Connect

    Nicholas R. Soelberg; Doug Marshall; Dean Taylor; Steven Bates

    2004-01-01

    About one million gallons of acidic, hazardous, and radioactive sodium-bearing waste (SBW) is stored in stainless steel tanks a the Idaho Nuclear Technology and Engineering Center (INTEC), which is a major operating facility of the Idaho National Engineering and Environmental Laboratory (INEEL). Steam reforming is a candidate technology being investigated for converting the SBW into a road ready waste form that can be shipped to the Waste Isolation Pilot Plant in New Mexico for interment. Fluidized bed steam reforming technology, licensed to ThermoChem Waste Remediation, LLC (TWR) by Manufacturing Technology Conversion International, was tested in two phases using an INEEL (Department of Energy) fluidized bed test system located at the Science Applications International Corporation (SAIC) Science and Technology Applications Research Center in Idaho Falls, Idaho. The Phase 1 tests were reported earlier. The Phase 2 tests are reported here. For Phase 2, the process feed rate, reductant stoichiometry, and process temperature were varied to identify and demonstrate how the process might be optimized to improve operation and product characteristics. The first week of testing was devoted primarily to process chemistry and the second week was devoted more toward bed stability and particle size control.

  14. Process Options Description for Vitrification Flowsheet Model of INEEL Sodium Bearing Waste

    SciTech Connect

    Nichols, T.T.; Taylor, D.D.; Lauerhass, L.; Barnes, C.M.

    2002-02-21

    The technical information required for the development of a basic steady-state process simulation of the vitrification treatment train of sodium bearing waste (SBW) at Idaho National Engineering and Environmental Laboratory (INEEL) is presented. The objective of the modeling effort is to provide the predictive capability required to optimize an entire treatment train and assess system-wide impacts of local changes at individual unit operations, with the aim of reducing the schedule and cost of future process/facility design efforts. All the information required a priori for engineers to construct and link unit operation modules in a commercial software simulator to represent the alternative treatment trains is presented. The information is of a mid- to high-level nature and consists of the following: (1) a description of twenty-four specific unit operations--their operating conditions and constraints, primary species and key outputs, and the initial modeling approaches that will be used in the first year of the simulation's development; (2) three potential configurations of the unit operations (trains) and their interdependencies via stream connections; and (3) representative stream compositional makeups.

  15. Sulfur Partitioning During Vitrification of INEEL Sodium Bearing Waste: Status Report

    SciTech Connect

    Darab, John G.; Graham, Dennis D.; Macisaac, Brett D.; Russell, Renee L.; Smith, Harry D.; Vienna, John D.; Peeler, David K.

    2001-07-31

    The sodium bearing tank waste (SBW) at Idaho National Engineering and Environmental Laboratory (INEEL) contains high concentrations of sulfur (roughly 5 mass% of SO3 on a nonvolatile oxide basis). The amount of sulfur that can be feed to the melter will ultimately determine the loading of SBW in glass produced by the baseline (low-temperature, joule-heated, liquid-fed, ceramic-lined) melter. The amount of sulfur which can be fed to the melter is determined by several major factors including: the tolerance of the melter for an immiscible salt layer accumulation, the solubility of sulfur in the glass melt, the fraction of sulfur removed to the off-gas, and the incorporation of sulfur into the glass up to it?s solubility limit. This report summarizes the current status of testing aimed at determining the impacts of key chemical and physical parameters on the partitioning of sulfur between the glass, a molten salt, and the off-gas.

  16. Composition and Simulation of Tank WM-180 Sodium Bearing Waste at INTEC

    SciTech Connect

    Christian, Jerry Dale

    2001-04-01

    The 1-million liters of sodium-bearing waste in the WM-180 tank at the Idaho Nuclear Technology and Engineering Center has been concentrated and will be the first to be processed, at its current composition, by vitrification to prepare the radioactive waste for disposition. The waste has been sampled and analyzed for cations, anions, and radionuclides in the liquid and in the small amount of solids that were entrained with the liquid during sampling. The analytical results have been evaluated and a non-radioactive simulant composition and preparation procedure developed and demonstrated to result in a clear solution. The evaluation and results are reported here. This simulant is suitable for performing laboratory and pilot-scale tests in order to develop the vitrification technology. The solids entrained from the tank with the liquid sample amount to 0.06% of the dissolved solids in the liquid. While their elemental and radionuclide composition was determined, qualitative characterization using x-ray diffraction was not possible. Because of the interest in the properties of solids that may be in the bottom of the WM-180 tank, for tank closure activities, thermodynamic modeling was performed of potential precipitates that may be in equilibrium with the solution. The results were used to derive a possible chemical composition of the solids.

  17. Thermal analysis for fuel handling system for sodium cooled reactor considering minor actinide-bearing metal fuel.

    SciTech Connect

    Chikazawa, Y.; Grandy, C.; Nuclear Engineering Division

    2009-03-01

    The Advanced Burner Reactor (ABR) is one of the components of the Global Nuclear Energy Partnership (GNEP) used to close the fuel cycle. ABR is a sodium-cooled fast reactor that is used to consume transuranic elements resulting from the reprocessing of light water reactor spent nuclear fuel. ABR-1000 [1000 MW(thermal)] is a fast reactor concept created at Argonne National Laboratory to be used as a reference concept for various future trade-offs. ABR-1000 meets the GNEP goals although it uses what is considered base sodium fast reactor technology for its systems and components. One of the considerations of any fast reactor plant concept is the ability to perform fuel-handling operations with new and spent fast reactor fuel. The transmutation fuel proposed as the ABR fuel has a very little experience base, and thus, this paper investigates a fuel-handling concept and potential issues of handling fast reactor fuel containing minor actinides. In this study, two thermal analyses supporting a conceptual design study on the ABR-1000 fuel-handling system were carried out. One analysis investigated passive dry spent fuel storage, and the other analysis investigated a fresh fuel shipping cask. Passive dry storage can be made suitable for the ABR-1000 spent fuel storage with sodium-bonded metal fuel. The thermal analysis shows that spent fast reactor fuel with a decay heat of 2 kW or less can be stored passively in a helium atmosphere. The 2-kW value seems to be a reasonable and practical level, and a combination of reasonably-sized in-sodium storage followed by passive dry storage could be a candidate for spent fuel storage for the next-generation sodium-cooled reactor with sodium-bonded metal fuel. Requirements for the shipping casks for minor actinide-bearing fuel with a high decay heat level are also discussed in this paper. The shipping cask for fresh sodium-cooled-reactor fuel should be a dry type to reduce the reaction between residual moisture on fresh fuel and the

  18. Characterization of Tank WM-189 Sodium-bearing Waste at INTEC, Rev. 1

    SciTech Connect

    Batcheller, Thomas Aquinas; Taylor, Dean Dalton

    2003-07-01

    Idaho Nuclear Technology and Engineering Center 300,000-gallon vessel WM-189 was filled in late 2001 with concentrated sodium bearing waste (SBW). Three airlifted liquid samples and a steam jetted slurry sample were obtained for quantitative analysis and characterization of WM-189 liquid phase SBW and tank heel sludge. Estimates were provided for most of the reported data values, based on the greater of (a) analytical uncertainty, and (b) variation of analytical results between nominally similar samples. A consistency check on the data was performed by comparing the total mass of dissolved solids in the liquid, as measured gravimetrically from a dried sample, with the corresponding value obtained by summing the masses of cations and anions in the liquid, based on the reported analytical data. After reasonable adjustments to the nitrate and oxygen concentrations, satisfactory consistency between the two results was obtained. A similar consistency check was performed on the reported compositional data for sludge solids from the steam jetted sample. In addition to the compositional data, various other analyses were performed: particle size distribution was measured for the sludge solids, sludge settling tests were performed, and viscosity measurements were made. WM-189 characterization results were compared with those for WM-180, and other Tank Farm Facility tank characterization data. A 2-liter batch of WM-189 simulant was prepared and a clear, stable solution was obtained, based on a general procedure for mixing SBW simulant that was develop by Dr. Jerry Christian. This WM-189 SBW simulant is considered suitable for laboratory testing for process development.

  19. Design and characterization of microporous zeolitic hydroceramic waste forms for the solidification and stabilization of sodium bearing wastes

    NASA Astrophysics Data System (ADS)

    Bao, Yun

    During the production of nuclear weapon by the DOE, large amounts of liquid waste were generated and stored in millions of gallons of tanks at Savannah River, Hanford and INEEL sites. Typically, the waste contains large amounts of soluble NaOH, NaNO2 and NaNO3 and small amounts of soluble fission products, cladding materials and cleaning solution. Due to its high sodium content it has been called sodium bearing waste (SBW). We have formulated, tested and evaluated a new type of hydroceramic waste form specifically designed to solidify SBW. Hydroceramics can be made from an alumosilicate source such as metakaolin and NaOH solutions or the SBW itself. Under mild hydrothermal conditions, the mixture is transformed into a solid consisting of zeolites. This process leads to the incorporation of radionuclides into lattice sites and the cage structures of the zeolites. Hydroceramics have high strength and inherent stability in realistic geologic settings. The process of making hydroceramics from a series of SBWs was optimized. The results are reported in this thesis. Some SBWs containing relatively small amounts of NaNO3 and NaNO2 (SigmaNOx/Sigma Na<25 mol%) can be directly solidified with metakaolin. The remaining SBW having high concentrations of nitrate and nitrite (SigmaNOx/Sigma Na>25 mol%) require pretreatment since a zeolitic matrix such as cancrinite is unable to host more than 25 mol% nitrate/nitrite. Two procedures to denitrate/denitrite followed by solidification were developed. One is based on calcination in which a reducing agent such as sucrose and metakaolin have been chosen as a way of reducing nitrate and nitrite to an acceptable level. The resulting calcine can be solidified using additional metakaolin and NaOH to form a hydroceramic. As an alternate, a chemical denitration/denitrition process using Si and Al powders as the reducing agents, followed by adding metakaolin to the solution prepare a hydroceramic was also investigated. Si and Al not only are

  20. Converting Simulated Sodium-bearing Waste into a Single Solid Waste Form by Evaporation: Laboratory- and Pilot-Scale Test Results on Recycling Evaporator Overheads

    SciTech Connect

    Griffith, D.; D. L. Griffith; R. J. Kirkham; L. G. Olson; S. J. Losinski

    2004-01-01

    Conversion of Idaho National Engineering and Environmental Laboratory radioactive sodium-bearing waste into a single solid waste form by evaporation was demonstrated in both flask-scale and pilot-scale agitated thin film evaporator tests. A sodium-bearing waste simulant was adjusted to represent an evaporator feed in which the acid from the distillate is concentrated, neutralized, and recycled back through the evaporator. The advantage to this flowsheet is that a single remote-handled transuranic waste form is produced in the evaporator bottoms without the generation of any low-level mixed secondary waste. However, use of a recycle flowsheet in sodium-bearing waste evaporation results in a 50% increase in remote-handled transuranic volume in comparison to a non-recycle flowsheet.

  1. Laser fluorescence studies of the chemical interactions of sodium species with sulfur bearing fuels

    NASA Technical Reports Server (NTRS)

    Steinberg, M.; Schofield, K.

    1983-01-01

    By using a large matrix of fuel rich and fuel lean H2/O2/N2 and fuel rich C2H2/O2/N2 flames, the behavior of sodium and its interactions with sulfur at high temperatures was extensively characterized. OH concentrations were measured for each flame using the previously validated laser induced fluorescence technique. Sodium atomic concentrations were obtained by the saturated laser fluorescence method. Measurements were made in the absence and presence of up to 2% sulfur. In oxygen rich systems sodium is depleted by NaO2 and NaOH formation. The relative amounts of each are controlled by the degree of nonequilibration of the flame radicals and by the temperature. The bond strength of NaO2 was established. For the first time, a complete understanding of the complex behavior of sodium in fuel lean H2/O2 flames has emerged and computer modeling has permitted various rate constants of Na, NaO2 and NaOH reactions to be approximately fixed.

  2. Spectrophotometric determination of fluoride in fluoride-bearing minerals after decomposition by fusion with sodium hydroxide.

    PubMed

    Adelantado, J V; Martinez, V P; Moreno, A C; Reig, F B

    1985-03-01

    The decomposition of highly insoluble minerals (fluorspar and cryolite) by fusion with molten alkali-metal hydroxides is studied. The introduction of additives such as aluminium compounds or sodium peroxide to obtain total liberation of fluoride from calcium fluoride samples, is tested. The fusion is done in a silver crucible with a Bunsen burner. The cooled melt is easily soluble, giving solutions suitable for spectrophotometric fluoride determination by the Zr(IV)-fluoride-Erichrome Cyanine R method. PMID:18963832

  3. Testing and Disposal Strategy for Secondary Wastes from Vitrification of Sodium-Bearing Waste at the Idaho Nuclear Technology and Engineering Center

    SciTech Connect

    Herbst, Alan Keith

    2002-01-01

    The Idaho National Engineering and Environmental Laboratory (INEEL) is considering vitrification to process liquid sodium-bearing waste. Preliminary studies were completed to evaluate the potential secondary wastes comprise acidic and caustic scrubber solutions, HEPA filters, activated carbon, and ion exchange media. Possible treatment methods, waste forms, and disposal sites are evaluated from radiological and mercury contamination estimates.

  4. Testing and Disposal Strategy for Secondary Wastes from Vitrification of Sodium-Bearing Waste at Idaho Nuclear Technology and Engineering Center

    SciTech Connect

    Herbst, Alan K.

    2002-01-02

    The Idaho National Engineering and Environmental Laboratory (INEEL) is considering vitrification to process liquid sodium-bearing waste. Preliminary studies were completed to evaluate the potential secondary wastes comprise acidic and caustic scrubber solutions, HEPA filters, activated carbon, and ion exchange media. Possible treatment methods, waste forms, and disposal sites are evaluated from radiological and mercury contamination estimates.

  5. Out-Of-Drum Grout Mixer Testing With Simulated Liquid Effluents Originating From Sodium-Bearing Waste at the Idaho Nuclear Technology and Engineering Center

    SciTech Connect

    B. A. Scholes; A. K. Herbst; S. V. Raman; S. H. Hinckley

    2003-09-01

    The Idaho National Engineering and Environmental Laboratory (INEEL) is considering several optional processes for disposal of liquid sodium-bearing waste. During fiscal year 2003, alternatives were evaluated for grout formulation development and associated mixing for the Sodium-Bearing Waste cesium ion exchange process. The neutralization agents calcium or sodium hydroxide and the solidification agents Portland cement, with or without blast furnace slag were evaluated. A desired uniform formulation was pursued to develop a grout waste form without any bleed liquid and solidify within a reasonable period of about twenty-eight days. This testing evaluates the out-of-drum alternative of mixing the effluent with solidification agents prior to being poured into drums versus the in-drum alternative of mixing them all together after being poured into the drums. Experimental results indicate that sodium-bearing waste can be immobilized in grout using the Autocon continuous mixer within the range of 66 to 72 weight percent. Furthermore, a loading of 30 weight percent NWCF scrubber simulant also produced an acceptable grout waste form.

  6. Baseline Flowsheet Generation for the Treatment and Disposal of Idaho National Engineering and Environmental Laboratory Sodium Bearing Waste

    SciTech Connect

    Barnes, Charles Marshall; Lauerhass, Lance; Olson, Arlin Leland; Taylor, Dean Dalton; Valentine, James Henry; Lockie, Keith Andrew

    2002-02-01

    The High-Level Waste (HLW) Program at the Idaho National Engineering and Environmental Laboratory (INEEL) must implement technologies and processes to treat and qualify radioactive wastes located at the Idaho Nuclear Technology and Engineering Center (INTEC) for permanent disposal. This paper describes the approach and accomplishments to date for completing development of a baseline vitrification treatment flowsheet for sodium-bearing waste (SBW), including development of a relational database used to manage the associated process assumptions. A process baseline has been developed that includes process requirements, basis and assumptions, process flow diagrams, a process description, and a mass balance. In the absence of actual process or experimental results, mass and energy balance data for certain process steps are based on assumptions. Identification, documentation, validation, and overall management of the flowsheet assumptions are critical to ensuring an integrated, focused program. The INEEL HLW Program initially used a roadmapping methodology, developed through the INEEL Environmental Management Integration Program, to identify, document, and assess the uncertainty and risk associated with the SBW flowsheet process assumptions. However, the mass balance assumptions, process configuration and requirements should be accessible to all program participants. This need resulted in the creation of a relational database that provides formal documentation and tracking of the programmatic uncertainties related to the SBW flowsheet.

  7. Baseline Flowsheet Generation for the Treatment and Disposal of Idaho National Engineering and Environmental Laboratory Sodium Bearing Waste

    SciTech Connect

    Barnes, C.M.; Lauerhass, L.; Olson, A.L.; Taylor, D.D.; Valentine, J.H.; Lockie, K.A.

    2002-01-16

    The High-Level Waste (HLW) Program at the Idaho National Engineering and Environmental Laboratory (INEEL) must implement technologies and processes to treat and qualify radioactive wastes located at the Idaho Nuclear Technology and Engineering Center (INTEC) for permanent disposal. This paper describes the approach and accomplishments to date for completing development of a baseline vitrification treatment flowsheet for sodium-bearing waste (SBW), including development of a relational database used to manage the associated process assumptions. A process baseline has been developed that includes process requirements, basis and assumptions, process flow diagrams, a process description, and a mass balance. In the absence of actual process or experimental results, mass and energy balance data for certain process steps are based on assumptions. Identification, documentation, validation, and overall management of the flowsheet assumptions are critical to ensuring an integrated, focused program. The INEEL HLW Program initially used a roadmapping methodology, developed through the INEEL Environmental Management Integration Program, to identify, document, and assess the uncertainty and risk associated with the SBW flowsheet process assumptions. However, the mass balance assumptions, process configuration and requirements should be accessible to all program participants. This need resulted in the creation of a relational database that provides formal documentation and tracking of the programmatic uncertainties related to the SBW flowsheet.

  8. FY-97 operations of the pilot-scale glass melter to vitrify simulated ICPP high activity sodium-bearing waste

    SciTech Connect

    Musick, C.A.

    1997-11-01

    A 3.5 liter refractory-lined joule-heated glass melter was built to test the applicability of electric melting to vitrify simulated high activity waste (HAW). The HAW streams result from dissolution and separation of Idaho Chemical Processing Plant (ICPP) calcines and/or radioactive liquid waste. Pilot scale melter operations will establish selection criteria needed to evaluate the application of joule heating to immobilize ICPP high activity waste streams. The melter was fabricated with K-3 refractory walls and Inconel 690 electrodes. It is designed to be continuously operated at 1,150 C with a maximum glass output rate of 10 lbs/hr. The first set of tests were completed using surrogate HAW-sodium bearing waste (SBW). The melter operated for 57 hours and was shut down due to excessive melt temperatures resulting in low glass viscosity (< 30 Poise). Due to the high melt temperature and low viscosity the molten glass breached the melt chamber. The melter has been dismantled and examined to identify required process improvement areas and successes of the first melter run. The melter has been redesigned and is currently being fabricated for the second run, which is scheduled to begin in December 1997.

  9. Secondary Waste Considerations for Vitrification of Sodium-Bearing Waste at the Idaho Nuclear Technology and Engineering Center FY-2001 Status Report

    SciTech Connect

    Herbst, A.K.; Kirkham, R.J.; Losinski, S.J.

    2002-09-26

    The Idaho Nuclear Technology and Engineering Center (INTEC) is considering vitrification to process liquid sodium-bearing waste. Preliminary studies were completed to evaluate the potential secondary wastes from the melter off-gas clean up systems. Projected secondary wastes comprise acidic and caustic scrubber solutions, HEPA filters, activated carbon, and ion exchange media. Possible treatment methods, waste forms, and disposal sites are evaluated from radiological and mercury contamination estimates.

  10. Secondary Waste Considerations for Vitrification of Sodium-Bearing Waste at the Idaho Nuclear Techology and Engineering Center FY-2001 Status Report

    SciTech Connect

    Herbst, Alan Keith; Kirkham, Robert John; Losinski, Sylvester John

    2001-09-01

    The Idaho Nuclear Technology and Engineering Center (INTEC) is considering vitrification to process liquid sodium-bearing waste. Preliminary studies were completed to evaluate the potential secondary wastes from the melter off-gas clean up systems. Projected secondary wastes comprise acidic and caustic scrubber solutions, HEPA filters, activated carbon, and ion exchange media. Possible treatment methods, waste forms, and disposal sites are evaluated from radiological and mercury contamination estimates.

  11. Demonstration of a SREX flowsheet for the partitioning of strontium and lead from actual ICPP sodium-bearing waste

    SciTech Connect

    Law, J.D.; Wood, D.J.; Olson, L.G.; Todd, T.A.

    1997-08-01

    Laboratory experimentation has indicated that the SREX process is effective for partitioning {sup 90}Sr and Pb from acidic radioactive waste solutions located at the Idaho Chemical Processing Plant. Previous countercurrent flowsheet testing of the SREX process with simulated waste resulted in 99.98% removal of Sr and 99.9% removal of Pb. Based on the results of these studies, a demonstration of the SREX flowsheet was performed. The demonstration consisted of (1) countercurrent flowsheet testing of the SREX process using simulated sodium-bearing waste spiked with {sup 85}Sr and (2) countercurrent flowsheet testing of the SREX process using actual waste from tank WM-183. All testing was performed using 24 stages of 2-cm diameter centrifugal contactors which are installed in the Remote Analytical Laboratory hot cell. The flowsheet tested consisted of an extraction section (0. 15 M 4`,4`(5)-di-(tert-butyldicyclohexo)-18-crown-6 and 1.5 M TBP in Isopar-L{reg_sign}), a 2.0 MHNO{sub 3} scrub section to remove extracted K from the SREX solvent, a 0.05 M HNO{sub 3} strip section for the removal of Sr from the SREX solvent, a 0.1 M ammonium citrate strip section for the removal of Pb from the SREX solvent, and a 3.0 M HNO{sub 3} equilibration section. The behavior of {sup 90}Sr, Pb, Na, K, Hg, H{sup +}, the actinides, and numerous other non-radioactive elements was evaluated. The described flowsheet successfully extracted and selectively stripped Sr and Ph from the SBW simulant and the actual tank waste. For the testing with actual tank waste (WM - 183), removal efficiencies of 99.995 % and >94% were obtained for {sup 90}Sr and Pb, respectively.

  12. DURABILITY TESTING OF FLUIDIZED BED STEAM REFORMER WASTE FORMS FOR SODIUM BEARING WASTE AT IDAHO NATIONAL LABORATORY

    SciTech Connect

    Crawford, C; Carol Jantzen, C

    2007-08-27

    Fluidized Bed Steam Reforming (FBSR) processing of Sodium Bearing Waste simulants was performed in December 2006 by THOR{sup sm} Treatment Technologies LLC (TTT) The testing was performed at the Hazen Research Inc. (HRI) pilot plant facilities in Golden, CO. FBSR products from these pilot tests on simulated waste representative of the SBW at the Idaho Nuclear Technology and Engineering Center (INTEC) were subsequently transferred to the Savannah River National Laboratory (SRNL) for characterization and leach testing. Four as-received Denitration and Mineralization Reformer (DMR) granular/powder samples and four High Temperature Filter (HTF) powder samples were received by SRNL. FBSR DMR samples had been taken from the ''active'' bed, while the HTF samples were the fines collected as carryover from the DMR. The process operated at high fluidizing velocities during the mineralization test such that nearly all of the product collected was from the HTF. Active bed samples were collected from the DMR to monitor bed particle size distribution. Characterization of these crystalline powder samples shows that they are primarily Al, Na and Si, with > 1 wt% Ca, Fe and K. The DMR samples contained less than 1 wt% carbon and the HTF samples ranged from 13 to 26 wt% carbon. X-ray diffraction analyses show that the DMR samples contained significant quantities of the Al{sub 2}O{sub 3} startup bed. The DMR samples became progressively lower in starting bed alumina with major Na/Al/Si crystalline phases (nepheline and sodium aluminosilicate) present as cumulative bed turnover occurred but 100% bed turnover was not achieved. The HTF samples also contained these major crystalline phases. Durability testing of the DMR and HTF samples using the ASTM C1285 Product Consistency Test (PCT) 7-day leach test at 90 C was performed along with several reference glass samples. Comparison of the normalized leach rates for the various DMR and HTF components was made with the reference glasses and

  13. Does taurine deficiency cause metabolic bone disease and rickets in polar bear cubs raised in captivity?

    PubMed

    Chesney, Russell W; Hedberg, Gail E; Rogers, Quinton R; Dierenfeld, Ellen S; Hollis, Bruce E; Derocher, Andrew; Andersen, Magnus

    2009-01-01

    Rickets and fractures have been reported in captive polar bears. Taurine (TAU) is key for the conjugation of ursodeoxycholic acid (UDCA), a bile acid unique to bears. Since TAU-conjugated UDCA optimizes fat and fat-soluble vitamin absorption, we asked if TAU deficiency could cause vitamin D malabsorption and lead to metabolic bone disease in captive polar bears. We measured TAU levels in plasma (P) and whole blood (WB) from captive and free-ranging cubs and adults, and vitamin D3 and TAU concentrations in milk samples from lactating sows. Plasma and WB TAU levels were significantly higher in cubs vs captive and free-ranging adult bears. Vitamin D in polar bear milk was 649.2 +/- 569.2 IU/L, similar to that found in formula. The amount of TAU in polar bear milk is 3166.4 +/- 771 nmol/ml, 26-fold higher than in formula. Levels of vitamin D in bear milk and formula as well as in plasma do not indicate classical nutritional vitamin D deficiency. Higher dietary intake of TAU by free-ranging cubs may influence bile acid conjugation and improve vitamin D absorption. PMID:19239163

  14. Does Replacing Sodium Excreted in Sweat Attenuate the Health Benefits of Physical Activity?

    PubMed

    Turner, Martin J; Avolio, Alberto P

    2016-08-01

    International guidelines suggest limiting sodium intake to 86-100 mmol/day, but average intake exceeds 150 mmol/day. Participants in physical activities are, however, advised to increase sodium intake before, during and after exercise to ensure euhydration, replace sodium lost in sweat, speed rehydration and maintain performance. A similar range of health benefits is attributable to exercise and to reduction in sodium intake, including reductions in blood pressure (BP) and the increase of BP with age, reduced risk of stroke and other cardiovascular diseases, and reduced risk of osteoporosis and dementia. Sweat typically contains 40-60 mmol/L of sodium, leading to approximately 20-90 mmol of sodium lost in one exercise session with sweat rates of 0.5-1.5 L/h. Reductions in sodium intake of 20-90 mmol/day have been associated with substantial health benefits. Homeostatic systems reduce sweat sodium as low as 3-10 mmol/L to prevent excessive sodium loss. "Salty sweaters" may be individuals with high sodium intake who perpetuate their "salty sweat" condition by continual replacement of sodium excreted in sweat. Studies of prolonged high intensity exercise in hot environments suggest that sodium supplementation is not necessary to prevent hyponatremia during exercise lasting up to 6 hr. We examine the novel hypothesis that sodium excreted in sweat during physical activity offsets a significant fraction of excess dietary sodium, and hence may contribute part of the health benefits of exercise. Replacing sodium lost in sweat during exercise may improve physical performance, but may attenuate the long-term health benefits of exercise. PMID:26841436

  15. Optimization of hydraulic cement admixture waste forms for sodium-bearing, high aluminum, and high zirconium wastes

    SciTech Connect

    Herbst, A.K.

    1997-08-01

    A three-way blend of portland cement, blast furnace slag, and fly ash was successfully tested on simulated acidic high sodium, aluminum, and zirconium low-level wastes (LLW). Grout cubes were prepared at various waste loadings to maximize loading while meeting compressive strength and leach resistance requirements. For sodium LLW, a 21% waste loading achieves a volume reduction of 3.3 and a compressive strength of 2750 pounds per square inch while meeting leach, mix, and flow requirements. It was found that the sulfur in the slag reduces the chromium leach rate below regulatory limits. For aluminum LLW, a 10% waste loading achieves a volume reduction of 8.5 and a compressive strength of 4.50 pounds per square inch while meeting leach requirements. Likewise for zirconium LLW, a 21% waste loading achieves a volume reduction of 8.3 and a compressive strength of 3570 pounds per square inch.

  16. Immobilization of sodium and phosphorus-bearing PW-7a waste in SYNROC. Progress report. [SYNROC C

    SciTech Connect

    Ringwood, A.E.

    1982-08-09

    The phosphorus, sodium and gadolinium-rich PW-7a waste can be successfully incorporated in SYNROC-C. However, a new accessory phase, a Ca,Na,Ba phosphate isostructural with Ca/sub 5/Na/sub 2/(PO/sub 4/)/sub 4/ apppears in the SYNROC mineralogy. There is no evidence for the partition of key radionuclides (e.g. Sr, REE and hence actinides) into this phosphate. Its poor resistance to groundwater dissolution, whilst hardly desirable, may therefore not have a serious effect on the leaching performance of SYNROC containing PW-7a. 9 tables.

  17. Does oral buffered sodium supplementation reduce nausea and vomiting during an ultramarathon?

    PubMed

    Hoffman, Martin D; Stuempfle, Kristin J

    2016-01-01

    This work examines whether nausea or vomiting during an ultramarathon are due to a fluid or electrolyte imbalance, and if these symptoms can be reduced through the use of buffered sodium supplements. Starters (n = 376) of a 161.3-km ultramarathon underwent body weight measurements, 74.5% completed a post-race questionnaire, and 53.0% also underwent a post-race blood draw. The incidence of nausea or vomiting progressively increased during the race, and affected 60% of runners overall. Weight change and rate of sodium intake in supplements or in buffered sodium supplements did not differ between those with and without nausea or vomiting. Post-race serum sodium concentration also did not differ between those with and without symptoms in the last race segment. We conclude that weight change, the rate of sodium intake in supplements or in buffered sodium supplements, and serum sodium concentration are not related to symptoms of nausea or vomiting during a 161-km ultramarathon. PMID:26967492

  18. Grizzly bear

    USGS Publications Warehouse

    Schwartz, C.C.; Miller, S.D.; Haroldson, M.A.

    2003-01-01

    The grizzly bear inspires fear, awe, and respect in humans to a degree unmatched by any other North American wild mammal. Like other bear species, it can inflict serious injury and death on humans and sometimes does. Unlike the polar bear (Ursus maritimus) of the sparsely inhabited northern arctic, however, grizzly bears still live in areas visited by crowds of people, where presence of the grizzly remains physically real and emotionally dominant. A hike in the wilderness that includes grizzly bears is different from a stroll in a forest from which grizzly bears have been purged; nighttime conversations around the campfire and dreams in the tent reflect the presence of the great bear. Contributing to the aura of the grizzly bear is the mixture of myth and reality about its ferocity. unpredictable disposition, large size, strength, huge canines, long claws, keen senses, swiftness, and playfulness. They share characteristics with humans such as generalist life history strategies. extended periods of maternal care, and omnivorous diets. These factors capture the human imagination in ways distinct from other North American mammals. Precontact Native American legends reflected the same fascination with the grizzly bear as modern stories and legends (Rockwell 1991).

  19. Does Mama Bear Always Serve the Porridge? Sex-Role Stereotyping in School Reading Materials.

    ERIC Educational Resources Information Center

    Hagar, Margaret E.; Deffenbaugh, Sue

    Sex role stereotyping is the process by which people are defined by their sex rather than by their thoughts, feelings, interests, and abilities. It is the portrayal of people in typical situations as determined by their sex and does not allow either males or females to express the totality of their humanity. This paper discusses the problem of sex…

  20. Novel papillomavirus isolated from the oral mucosa of a polar bear does not cluster with other papillomaviruses of carnivores.

    PubMed

    Stevens, Hans; Rector, Annabel; Bertelsen, Mads F; Leifsson, Pall S; Van Ranst, Marc

    2008-05-25

    Papillomatosis has been documented in several carnivores, and papillomavirus (PV) types have been characterized from lesions in a number of carnivore species: the canine oral PV (COPV), the Felis domesticus PV type 1 (FdPV-1) isolated from a Persian cat, the Procyon lotor PV type 1 (PlPV-1) isolated from a raccoon, the canine PV type 2 (CPV-2) from a dog's foot pad lesion and the canine PV type 3 (CPV-3) associated with a canine epidermodysplasia verruciformis - like disease. A tissue sample was taken from a papillomatous lesion on the oral mucosa of a polar bear (Ursus maritimus). Extracted DNA was used as a template for multiply primed rolling-circle amplification (RCA), and restriction enzyme analysis of the RCA product indicated the presence of papillomaviral DNA. The genome of this PV was cloned and the complete genomic sequence was determined. The Ursus maritimus PV type 1 (UmPV-1) genome counts 7582 basepairs and is smaller than that of other papillomaviruses from carnivore species. UmPV-1 contains the typical noncoding region NCR1, but unlike the carnivore PVs of the Lambda genus, UmPV-1 does not possess a second noncoding region NCR2. Phylogenetic analysis based on a nucleotide sequence alignment of the L1 ORF of UmPV-1 and 51 other PV types indicates that UmPV-1 does not cluster with any of the other carnivore PVs, but branches off near the root of the common branch of the genus Alphapapillomavirus. PMID:18215475

  1. Lawrence Livermore National Laboratory Measurements of Plutonium-bearing Oxide in DOE-STD-3013-2000 Containers Using Calorimetry and Gamma Isotopic Analyses

    SciTech Connect

    Dearborn, D M; Keeton, S C

    2004-06-23

    Lawrence Livermore National Laboratory (LLNL) routinely uses calorimetry and gamma isotopic analyses (Cal/Iso) for the accountability measurement of plutonium (Pu) bearing items. In the past 15 years, the vast majority of those items measured by Cal/Iso were contained in a thin-walled convenience can enclosed in another thin-walled outer container. However, LLNL has recently begun to use DOE-STD-3013-2000 containers as well. These DOE-STD-3013-2000 containers are comprised of a stainless steel convenience can enclosed in welded stainless steel primary and secondary containers. In addition to the fact that the wall thickness of the DOE-STD-3013-2000 containers is much greater than that of other containers in our experience, the DOE-STD-3013-2000 containers appear to have larger thermal insulation characteristics. To date, we have derived Pu-mass values from Cal/Iso measurements of 74 different DOE-STD-3013-2000 containers filled with Pu-bearing oxide or mixed uranium-plutonium (U-Pu) oxide material. Both water-bath and air-bath calorimeters were used for these measurements and both use software to predict when thermal equilibrium is attained. Our experience has shown that after apparent equilibrium has been attained, at least one more complete cycle, and sometimes two or three more complete cycles, is required to gain a measure of true thermal equilibrium. Otherwise, the derived Pu-mass values are less than would be expected from a combination of previously measured Pu-bearing items and would contribute to increased loss in our inventory difference determinations. Conclusions and recommendations drawn from LLNL experience with measurements of Pu mass in Pu-bearing oxide or mixed U-Pu oxide in DOE-STD-3013-2000 containers using the Cal/Iso technique are included.

  2. Sodium selenite supplementation does not fully restore oxidative stress-induced deiodinase dysfunction: Implications for the nonthyroidal illness syndrome

    PubMed Central

    Wajner, Simone Magagnin; Rohenkohl, Helena Cecin; Serrano, Tulio; Maia, Ana Luiza

    2015-01-01

    Nonthyroidal illness syndrome (NTIS) is marked by low T3 and high reverse T3 levels. The physiopathology is poorly understood but involves oxidative stress-induced disruption of the iodothyronine deiodinases, which activate or inactivate thyroid hormones. Selenium, an essential trace element, exerts antioxidant function mainly through the thioredoxin reductase (TRx) and glutathione peroxidase (GPx) redox-regulating systems. We evaluated the effect of sodium selenite on IL6-induced disruption on deiodinase function. Cell lines expressing endogenous deiodinases type 1(D1), 2(D2) or 3(D3) (HepG2, MSTO, and MCF-7 cells, respectively) were used in an intact cell model that mimics the deiodination process under physiological conditions of substrate and cofactor, in the presence or not of IL6, with or without selenite. Deiodinase activity was quantified by the amount of iodine-125 in the medium (D1 and D2) or by ion-exchange chromatography (D3). Oxidative stress was evaluated by measuring reactive species (RS), carbonyl content as well as enzymatic and non-enzymatic antioxidant defenses. Results: IL6 induced ROS and carbonyl content in all 3 cell lines (all P<0.001). Increased ROS was paralleled by D1 and D2-decreased T3-production (P<0.01) and increased D3-catalyzed T3-inactivation (P<0.001). Selenite decreases the IL6-induced ROS and carbonyl content, while enhances Gpx and Trx activities. Nevertheless, it failed on restoring D1 or D2 function and only attenuates D3 activation (P<0.05). In conclusion, although sodium selenite reduces IL6-induced redox imbalance it does not fully repair deiodinase function. These results shed light on NTIS physiopathology and might explain why low T3 levels are unaffected by selenium supplementation in sick patients. PMID:26402162

  3. A single dose of sodium nitrate does not improve oral glucose tolerance in patients with type 2 diabetes mellitus.

    PubMed

    Cermak, Naomi M; Hansen, Dominique; Kouw, Imre W K; van Dijk, Jan-Willem; Blackwell, Jamie R; Jones, Andrew M; Gibala, Martin J; van Loon, Luc J C

    2015-08-01

    Dietary nitrate (NO3(-)) supplementation has been proposed as an emerging treatment strategy for type 2 diabetes. We hypothesized that ingestion of a single bolus of dietary NO3(-) ingestion improves oral glucose tolerance in patients with type 2 diabetes. Seventeen men with type 2 diabetes (glycated hemoglobin, 7.3% ± 0.2%) participated in a randomized crossover experiment. The subjects ingested a glucose beverage 2.5 hours after consumption of either sodium NO3(-) (0.15 mmol NaNO3(-) · kg(-1)) or a placebo solution. Venous blood samples were collected before ingestion of the glucose beverage and every 30 minutes thereafter during a 2-hour period to assess postprandial plasma glucose and insulin concentrations. The results show that plasma NO3(-) and nitrite levels were increased after NaNO3(-) as opposed to placebo ingestion (treatment-effect, P = .001). Despite the elevated plasma NO3(-) and nitrite levels, ingestion of NaNO3(-) did not attenuate the postprandial rise in plasma glucose and insulin concentrations (time × treatment interaction, P = .41 for glucose, P = .93 for insulin). Despite the lack of effect on oral glucose tolerance, basal plasma glucose concentrations measured 2.5 hours after NaNO3(-) ingestion were lower when compared with the placebo treatment (7.5 ± 0.4 vs 8.3 ± 0.4 mmol/L, respectively; P = .04). We conclude that ingestion of a single dose of dietary NO3(-) does not improve subsequent oral glucose tolerance in patients with type 2 diabetes. PMID:26092495

  4. Bearing system

    DOEpatents

    Kapich, Davorin D.

    1987-01-01

    A bearing system includes backup bearings for supporting a rotating shaft upon failure of primary bearings. In the preferred embodiment, the backup bearings are rolling element bearings having their rolling elements disposed out of contact with their associated respective inner races during normal functioning of the primary bearings. Displacement detection sensors are provided for detecting displacement of the shaft upon failure of the primary bearings. Upon detection of the failure of the primary bearings, the rolling elements and inner races of the backup bearings are brought into mutual contact by axial displacement of the shaft.

  5. Synergistic ablation does not affect atrophy or altered myosin heavy chain expression in the non-weight bearing soleus muscle

    NASA Technical Reports Server (NTRS)

    Linderman, J. K.; Talmadge, R. J.; Gosselink, K. L.; Tri, P. N.; Roy, R. R.; Grindeland, R. E.

    1996-01-01

    The purpose of this study was to investigate whether the soleus muscle undergoes atrophy and alterations in myosin heavy chain (MHC) composition during non-weight bearing in the absence of synergists. Thirty-two female rats were randomly assigned to four groups: control (C), synergistic ablation (ABL) of the gastrocnemius and plantaris muscles to overload the soleus muscle, hindlimb suspension (HLS), or a combination of synergistic ablation and hindlimb suspension (HLS-ABL). After 28 days of hindlimb suspension, soleus atrophy was more pronounced in HLS (58%) than in HLS-ABL (43%) rats. Compared to C rats, non-weight bearing decreased mixed and myofibrillar protein contents and Type I MHC 49%, 45%, and 7%, respectively, in HLS animals. In addition, de novo expression of fast Type IIx and Type IIb MHC (5% and 2%, respectively) was observed in HLS animals. Similarly, when compared to C rats, mixed and myofibrillar protein contents and Type I MHC decreased 43%, 46%, and 4%, respectively, in HLS-ABL animals. Also, de novo expression of Type IIx (4%) and IIb (1%) MHC was observed. Collectively, these data indicate that the loss of muscle protein and Type I MHC, and the de novo expression of Type IIx and Type IIb MHC in the rat soleus occur independently of the presence of synergists during non-weight bearing. Furthermore, these results confirm the contention that soleus mass and MHC expression are highly sensitive to alterations in mechanical load.

  6. Effect of iron content on the structure and disorder of iron-bearing sodium silicate glasses: A high-resolution 29Si and 17O solid-state NMR study

    NASA Astrophysics Data System (ADS)

    Kim, Hyo-Im; Sur, Jung Chul; Lee, Sung Keun

    2016-01-01

    Despite its geochemical importance and implications for the properties of natural magmatic melts, understanding the detailed structure of iron-bearing silicate glasses remains among the outstanding problems in geochemistry. This is mainly because solid-state NMR techniques, one of the most versatile experimental methods to probe the structure of oxide glasses, cannot be fully utilized for exploring the structural details of iron-bearing glasses as the unpaired electrons in Fe induce strong local magnetic fields that mask the original spectroscopic features (i.e., paramagnetic effect). Here, we report high-resolution 29Si and 17O solid-state NMR spectra of iron-bearing sodium silicate glasses (Na2O-Fe2O3-SiO2, Fe3+/ΣFe = 0.89 ± 0.04, thus containing both ferric and ferrous iron) with varying XFe2O3 [=Fe2O3/(Na2O + Fe2O3)], containing up to 22.9 wt% Fe2O3. This compositional series involves Fe-Na substitution at constant SiO2 contents of 66.7 mol% in the glasses. For both nuclides, the NMR spectra exhibit a decrease in the signal intensities and an increase in the peak widths with increasing iron concentration partly because of the paramagnetic effect. Despite the intrinsic difficulties that result from the pronounced paramagnetic effect, the 29Si and 17O NMR results yield structural details regarding the effect of iron content on Q speciation, spatial distribution of iron, and the extent of polymerization in the iron-bearing silicate glasses. The 29Si NMR spectra show an apparent increase in highly polymerized Q species with increasing XFe2O3 , suggesting an increase in the degree of melt polymerization. The 17O 3QMAS NMR spectra exhibit well-resolved non-bridging oxygen (NBO, Na-O-Si) and bridging oxygen (BO, Si-O-Si) peaks with varying iron concentration. By replacing Na2O with Fe2O3 (and thus with increasing iron content), the fraction of Na-O-Si decreases. Quantitative consideration of this effect confirms that the degree of polymerization is likely to

  7. DOE STI Product/Final Report Number 3 Electrochemical Investigation of Novel Electrolytes for Ambient Temperature Sodium Batteries

    SciTech Connect

    Kim, Ketack; Lang, Christopher M.; Doyle, Kevin; Kohl, Paul A.

    2005-12-01

    The need for low-cost, high-energy density, durable, secondary batteries continues to rise with the demands of the electronics and automobile industries. A room-temperature version of the (high-temperature) ''Zebra Cell'' may provide an interesting technology for portable electronics and transportation. Sodium-based batteries have received attention as an alternative to the lithium-based batteries due to several factors including the absence of dendrite formation during sodium deposition and the abundance of sodium. This work focused on (1) the development of room-temperature ionic liquids (IL) for use in electrochemical devices, including batteries, (2) development and evaluation of secondary sodium batteries using room-temperature ILs, and (3) advancing the fundamental understanding of the electrochemical processes involving ILs and battery technology. Several objectives were accomplished during this program.

  8. Physical, Chemical and Structural Evolution of Zeolite-Containing Waste Forms Produced from Metakaolinite and Calcined Sodium Bearing Waste (HLW and/or LLW)

    SciTech Connect

    Grutzeck, Michael W.

    2005-06-27

    Zeolites are extremely versatile. They can adsorb liquids and gases and serve as cation exchange media. They occur in nature as well cemented deposits. The ancient Romans used blocks of zeolitized tuff as a building material. Using zeolites for the management of radioactive waste is not a new idea, but a process by which the zeolites can be made to act as a cementing agent is. Zeolitic materials are relatively easy to synthesize from a wide range of both natural and man-made substances. The process under study is derived from a well known method in which metakaolin (an impure thermally dehydroxylated kaolinite heated to {approx}700 C containing traces of quartz and mica) is mixed with sodium hydroxide (NaOH) and reacted in slurry form (for a day or two) at mildly elevated temperatures. The zeolites form as finely divided powders containing micrometer ({micro}m) sized crystals. However, if the process is changed slightly and only just enough concentrated sodium hydroxide solution is added to the metakaolinite to make a thick crumbly paste and then the paste is compacted and cured under mild hydrothermal conditions (60-200 C), the mixture will form a hard ceramic-like material containing distinct crystalline tectosilicate minerals (zeolites and feldspathoids) imbedded in an X-ray amorphous hydrated sodium aluminosilicate matrix. Due to its lack of porosity and vitreous appearance we have chosen to call this composite a ''hydroceramic''.

  9. Linear magnetic bearing

    NASA Technical Reports Server (NTRS)

    Studer, P. A. (Inventor)

    1983-01-01

    A linear magnetic bearing system having electromagnetic vernier flux paths in shunt relation with permanent magnets, so that the vernier flux does not traverse the permanent magnet, is described. Novelty is believed to reside in providing a linear magnetic bearing having electromagnetic flux paths that bypass high reluctance permanent magnets. Particular novelty is believed to reside in providing a linear magnetic bearing with a pair of axially spaced elements having electromagnets for establishing vernier x and y axis control. The magnetic bearing system has possible use in connection with a long life reciprocating cryogenic refrigerator that may be used on the space shuttle.

  10. N-Indolylglycosides bearing modifications at the glucose C6-position as sodium-dependent glucose co-transporter 2 inhibitors.

    PubMed

    Chu, Kuang-Feng; Yao, Chun-Hsu; Song, Jen-Shin; Chen, Chiung-Tong; Yeh, Teng-Kuang; Hsieh, Tsung-Chih; Huang, Chung-Yu; Wang, Min-Hsien; Wu, Szu-Huei; Chang, Wei-En; Chao, Yu-Sheng; Lee, Jinq-Chyi

    2016-05-15

    Suppression of glucose reabsorption through the inhibition of sodium-dependent glucose co-transporter 2 (SGLT2) is a promising therapeutic approach for the treatment of type 2 diabetes. To investigate the effect of C6-substitution on inhibition of SGLT2 by N-indolylglucosides, a small library of 6-triazole, 6-amide, 6-urea, and 6-thiourea N-indolylglycosides were synthesized and tested. A detailed structure-activity relationship (SAR) study culminated in the identification of 6-amide derivatives 6a and 6o as potent SGLT2 inhibitors, which were further tested for inhibitory activity against SGLT1. The data obtained indicated that 6a and 6o are mildly to moderately selective for SGLT2 over SGLT1. Both compounds were also evaluated in a urinary glucose excretion test and pharmacokinetic study; 6a was found capable of inducing urinary glucose excretion in normal SD rats. PMID:27075813

  11. Ad libitum Pasture Feeding in Late Pregnancy Does Not Improve the Performance of Twin-bearing Ewes and Their Lambs

    PubMed Central

    Corner-Thomas, R. A.; Back, P. J.; Kenyon, P. R.; Hickson, R. E.; Ridler, A. L.; Stafford, K. J.; Morris, S. T.

    2015-01-01

    The present study evaluated the effect of controlled ryegrass-white clover herbage availability from day 128 until day 142 of pregnancy in comparison to unrestricted availability, on the performance of twin-bearing ewes of varying body condition score (BCS; 2.0, 2.5, or 3.0) and their lambs. It was hypothesised that under conditions of controlled herbage availability, the performance of lambs born to ewes with a greater BCS would be greater than those born to ewes with a lower BCS. During the period that the nutritional regimens were imposed, the pre- and post-grazing herbage masses of the Control regimen (1,070±69 and 801±30 kg dry matter [DM]/ha) were lower than the ad libitum regimen (1,784±69 and 1,333±33 kg DM/ha; p<0.05). The average herbage masses during lactation were 1,410±31 kg DM/ha. Nutritional regimen had no effect on ewe live weight, BCS and back fat depth or on lamb live weight, indices of colostrum uptake, maximal heat production, total litter weight weaned or survival to weaning (p>0.05). The difference in ewe BCSs and back fats observed among body condition groups was maintained throughout pregnancy (p<0.05). At weaning, ewes from the BCS2.0 group had lower BCS and live weight (2.4±0.2, 74.3±2.6 kg) than both the BCS2.5 (2.6±0.2, 78.6±2.4 kg) and BCS3.0 ewes (2.7±0.2, 79.0±2.6 kg; p<0.05), which did not differ (p>0.05). Ewe BCS group had no effect on lamb live weight at birth or weaning or on maximal heat production (p>0.05). Serum gamma glutamyl transferase concentrations of lambs born to BCS3.0 ewes were higher within 36 hours of birth than lambs born to BCS2.0 ewes and BCS2.5 ewes (51.8±1.9 vs 46.5±1.9 and 45.6±1.9 IU/mL, respectively [p<0.05]). There was, however, no effect of ewe body condition on lamb plasma glucose concentration (p>0.05). Lamb survival was the only lamb parameter that showed an interaction between ewe nutritional regimen and ewe BCS whereby survival of lambs born to BCS2.5 and BCS3.0 ewes differed but only

  12. THRUST BEARING

    DOEpatents

    Heller, P.R.

    1958-09-16

    A thrust bearing suitable for use with a rotor or blower that is to rotate about a vertical axis is descrihed. A centrifagal jack is provided so thnt the device may opernte on one hearing at starting and lower speeds, and transfer the load to another bearing at higher speeds. A low viscosity fluid is used to lubricate the higher speed operation bearing, in connection with broad hearing -surfaces, the ability to withstand great loads, and a relatively high friction loss, as contraated to the lower speed operatio;n bearing which will withstand only light thrust loads but is sufficiently frictionfree to avoid bearing seizure during slow speed or startup operation. An axially aligned shaft pin provides the bearing surface for low rotational speeds, but at higher speed, weights operating against spring tension withdraw nthe shaft pin into the bearing proper and the rotor shaft comes in contact with the large bearing surfaces.

  13. Sodium waste technology: A summary report. [Melt-drain-evaporation-calcination (MEDEC)

    SciTech Connect

    Abrams, C.S.; Witbeck, L.C.

    1987-01-01

    The Sodium Waste Technology (SWT) Program was established to resolve long-standing issues regarding disposal of sodium-bearing waste and equipment. Comprehensive SWT research programs investigated a variety of approaches for either removing sodium from sodium-bearing items, or disposal of items containing sodium residuals. The most successful of these programs was the design, test, and the production operation of the Sodium Process Demonstration Facility at ANL-W. The technology used was a series of melt-drain-evaporate operations to remove nonradioactive sodium from sodium-bearing items and then converting the sodium to storable compounds.

  14. Serum sodium based modification of the MELD does not improve prediction of outcome in acute liver failure

    PubMed Central

    2013-01-01

    Background Acute liver failure (ALF) is a devastating clinical syndrome with a high mortality rate. The MELD score has been implied as a prognostic tool in ALF. Hyponatremia is associated with lethal outcome in ALF. Inclusion of serum sodium (Na) into the MELD score was found to improve its predictive value in cirrhotic patients. Therefore the aim of this study was to determine whether inclusion of serum Na improves the predictive value of MELD in ALF compared to established criteria. Methods In a prospective single center study (11/2006–12/2010), we recruited 108 consecutive ALF patients (64% females / 36% males), who met the criteria defined by the “Acute Liver Failure Study Group Germany”. Upon admission, clinical and laboratory data were collected, King’s College Criteria (KCC), Model of End Stage Liver Disease score (MELD), and serum sodium based modifications like the MELD-Na score and the United Kingdom Model of End Stage Liver Disease score (UKELD) were calculated and area under the receiver operating characteristic curve analyses were performed regarding the prediction of spontaneous recovery (SR) or non-spontaneous recovery (NSR; death or transplantation). Results Serum bilirubin was of no prognostic value in ALF, and Na also failed to predict NSR in ALF. The classical MELD score was superior to sodium-based modifications and KCC. Conclusions We validated the prognostic value of MELD-Na and UKELD in ALF. Classic MELD score calculations performed superior to KCC in the prediction of NSR. Serum Na and Na-based modifications of MELD did not further improve its prognostic value. PMID:23551795

  15. Journal bearing

    DOEpatents

    Menke, John R.; Boeker, Gilbert F.

    1976-05-11

    1. An improved journal bearing comprising in combination a non-rotatable cylindrical bearing member having a first bearing surface, a rotatable cylindrical bearing member having a confronting second bearing surface having a plurality of bearing elements, a source of lubricant adjacent said bearing elements for supplying lubricant thereto, each bearing element consisting of a pair of elongated relatively shallowly depressed surfaces lying in a cylindrical surface co-axial with the non-depressed surface and diverging from one another in the direction of rotation and obliquely arranged with respect to the axis of rotation of said rotatable member to cause a flow of lubricant longitudinally along said depressed surfaces from their distal ends toward their proximal ends as said bearing members are rotated relative to one another, each depressed surface subtending a radial angle of less than 360.degree., and means for rotating said rotatable bearing member to cause the lubricant to flow across and along said depressed surfaces, the flow of lubricant being impeded by the non-depressed portions of said second bearing surface to cause an increase in the lubricant pressure.

  16. Geophagy by yellowstone grizzly bears

    USGS Publications Warehouse

    Mattson, D.J.; Green, G.I.; Swalley, R.

    1999-01-01

    We documented 12 sites in the Yellowstone ecosystem where grizzly bears (Ursus arctos horribilis) had purposefully consumed soil (an activity known as geophagy). We also documented soil in numerous grizzly bear feces. Geophagy primarily occurred at sites barren of vegetation where surficial geology had been modified by geothermal activity. There was no evidence of ungulate use at most sites. Purposeful consumption of soil by bears peaked first from March to May and again from August to October, synchronous with peaks in consumption of ungulate meat and mushrooms. Geophageous soils were distinguished from ungulate mineral licks and soils in general by exceptionally high concentrations of potassium (K) and high concentrations of magnesium (Mg) and sulphur (S). Our results do not support the hypotheses that bears were consuming soil to detoxify secondary compounds in grazed foliage, as postulated for primates, or to supplement dietary sodium, as known for ungulates. Our results suggest that grizzly bears could have been consuming soil as an anti-diarrheal.

  17. The Switch from Low-Pressure Sodium to Light Emitting Diodes Does Not Affect Bat Activity at Street Lights

    PubMed Central

    Rowse, Elizabeth G.; Harris, Stephen; Jones, Gareth

    2016-01-01

    We used a before-after-control-impact paired design to examine the effects of a switch from low-pressure sodium (LPS) to light emitting diode (LED) street lights on bat activity at twelve sites across southern England. LED lights produce broad spectrum ‘white’ light compared to LPS street lights that emit narrow spectrum, orange light. These spectral differences could influence the abundance of insects at street lights and thereby the activity of the bats that prey on them. Most of the bats flying around the LPS lights were aerial-hawking species, and the species composition of bats remained the same after the switch-over to LED. We found that the switch-over from LPS to LED street lights did not affect the activity (number of bat passes), or the proportion of passes containing feeding buzzes, of those bat species typically found in close proximity to street lights in suburban environments in Britain. This is encouraging from a conservation perspective as many existing street lights are being, or have been, switched to LED before the ecological consequences have been assessed. However, lighting of all spectra studied to date generally has a negative impact on several slow-flying bat species, and LED lights are rarely frequented by these ‘light-intolerant’ bat species. PMID:27008274

  18. The Switch from Low-Pressure Sodium to Light Emitting Diodes Does Not Affect Bat Activity at Street Lights.

    PubMed

    Rowse, Elizabeth G; Harris, Stephen; Jones, Gareth

    2016-01-01

    We used a before-after-control-impact paired design to examine the effects of a switch from low-pressure sodium (LPS) to light emitting diode (LED) street lights on bat activity at twelve sites across southern England. LED lights produce broad spectrum 'white' light compared to LPS street lights that emit narrow spectrum, orange light. These spectral differences could influence the abundance of insects at street lights and thereby the activity of the bats that prey on them. Most of the bats flying around the LPS lights were aerial-hawking species, and the species composition of bats remained the same after the switch-over to LED. We found that the switch-over from LPS to LED street lights did not affect the activity (number of bat passes), or the proportion of passes containing feeding buzzes, of those bat species typically found in close proximity to street lights in suburban environments in Britain. This is encouraging from a conservation perspective as many existing street lights are being, or have been, switched to LED before the ecological consequences have been assessed. However, lighting of all spectra studied to date generally has a negative impact on several slow-flying bat species, and LED lights are rarely frequented by these 'light-intolerant' bat species. PMID:27008274

  19. Polar Bear

    USGS Publications Warehouse

    Amstrup, S.D.; DeMaster

    1988-01-01

    Polar bears are long-lived, late-maturing carnivores that have relatively low rates of reproduction and natural mortality. Their populations are susceptible to disturbance from human activities, such as the exploration and development of mineral resources or hunting. Polar bear populations have been an important renewable resource available to coastal communities throughout the Arctic for thousands of years.

  20. Fluoride coatings make effective lubricants in molten sodium environment

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Coating bearing surfaces with calcium fluoride-barium fluoride film provides effective lubrication against sliding friction in molten sodium and other severe environments at high and low temperatures.

  1. 21 CFR 573.700 - Sodium nitrite.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Sodium nitrite. 573.700 Section 573.700 Food and... Listing § 573.700 Sodium nitrite. Sodium nitrite may be safely used in canned pet food containing meat and... byproducts so that the level of sodium nitrite does not exceed 20 parts per million. (b) To assure safe...

  2. 21 CFR 573.700 - Sodium nitrite.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Sodium nitrite. 573.700 Section 573.700 Food and... Listing § 573.700 Sodium nitrite. Sodium nitrite may be safely used in canned pet food containing meat and... byproducts so that the level of sodium nitrite does not exceed 20 parts per million. (b) To assure safe...

  3. 21 CFR 573.700 - Sodium nitrite.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Sodium nitrite. 573.700 Section 573.700 Food and... Listing § 573.700 Sodium nitrite. Sodium nitrite may be safely used in canned pet food containing meat and... byproducts so that the level of sodium nitrite does not exceed 20 parts per million. (b) To assure safe...

  4. The sodium glucose cotransporter 2 inhibitor empagliflozin does not prolong QT interval in a thorough QT (TQT) study

    PubMed Central

    2013-01-01

    Background Empagliflozin is a potent, selective sodium glucose cotransporter 2 (SGLT2) inhibitor in development as an oral antidiabetic treatment. This QT interval study assessed potential effects of empagliflozin on ventricular repolarisation and other electrocardiogram (ECG) parameters. Methods A randomised, placebo-controlled, single-dose, double-blind, five-period crossover study incorporating a novel double-placebo period design to reduce sample size, while maintaining full statistical power. Treatments: single empagliflozin doses of 25 mg (therapeutic) and 200 mg (supratherapeutic), matching placebo and open-label moxifloxacin 400 mg (positive control). Triplicate 12-lead ECGs of 10 second duration were recorded at baseline and during the first 24 hours after dosing. The primary endpoint was mean change from baseline (MCfB) in the population heart rate-corrected QT interval (QTcN) between 1–4 hours after dosing. Results Thirty volunteers (16 male, 14 female, mean [range] age: 34.5 [18–52] years) were randomised. The placebo-corrected MCfB in QTcN 1–4 hours after dosing was 0.6 (90% CI: -0.7, 1.9) ms and -0.2 (-1.4, 0.9) ms for empagliflozin 25 mg and 200 mg, respectively, below the ICH E14 defined threshold of regulatory concern 10 ms. Assay sensitivity was confirmed by a placebo-corrected MCfB in QTcN 2–4 hours post-dose of 12.4 (10.7, 14.1) ms with moxifloxacin 400 mg. Empagliflozin tolerability was good for all volunteers; 23.3% experienced adverse events (AEs) with empagliflozin and 27.6% with placebo. The most frequent AE was nasopharyngitis. Conclusions/interpretation Single doses of empagliflozin 25 mg and 200 mg were not associated with QTcN prolongation and were well tolerated in healthy volunteers. Trial registration ClinicalTrials.gov: NCT01195675 PMID:23617452

  5. Magnetic Bearing

    NASA Technical Reports Server (NTRS)

    1996-01-01

    AVCON, Inc. produces advanced magnetic bearing systems for industrial use, offering a unique technological approach based on contract work done at Marshall Space Flight Center and Lewis Research Center. Designed for the turbopump of the Space Shuttle main engine, they are now used in applications such as electric power generation, petroleum refining, machine tool operation and natural gas pipelines. Magnetic bearings support moving machinery without physical contact; AVCON's homopolar approach is a hybrid of permanent and electromagnets which are one-third the weight, smaller and more power- efficient than previous magnetic bearings.

  6. Foil bearings

    NASA Technical Reports Server (NTRS)

    Elrod, David A.

    1993-01-01

    The rolling element bearings (REB's) which support many turbomachinery rotors offer high load capacity, low power requirements, and durability. Two disadvantages of REB's are: (1) rolling or sliding contact within the bearing has life-limiting consequences; and (2) REB's provide essentially no damping. The REB's in the Space Shuttle Main Engine (SSME) turbopumps must sustain high static and dynamic loads, at high speeds, with a cryogenic fluid as lubricant and coolant. The pump end ball bearings limit the life of the SSME high pressure oxygen turbopump (HPOTP). Compliant foil bearing (CFB) manufacturers have proposed replacing turbopump REB's with CFB's CFB's work well in aircraft air cycle machines, auxiliary power units, and refrigeration compressors. In a CFB, the rotor only contracts the foil support structure during start up and shut down. CFB damping is higher than REB damping. However, the load capacity of the CFB is low, compared to a REB. Furthermore, little stiffness and damping data exists for the CFB. A rotordynamic analysis for turbomachinery critical speeds and stability requires the input of bearing stiffness and damping coefficients. The two basic types of CFB are the tension-dominated bearing and the bending-dominated bearing. Many investigators have analyzed and measured characteristics of tension-dominated foil bearings, which are applied principally in magnetic tape recording. The bending-dominated CFB is used more in rotating machinery. This report describes the first phase of a structural analysis of a bending-dominated, multileaf CFB. A brief discussion of CFB literature is followed by a description and results of the present analysis.

  7. Sodium-Glucose Linked Cotransporter-2 Inhibition Does Not Attenuate Disease Progression in the Rat Remnant Kidney Model of Chronic Kidney Disease

    PubMed Central

    Zhang, Yanling; Thai, Kerri; Kepecs, David M.; Gilbert, Richard E.

    2016-01-01

    Pharmacological inhibition of the proximal tubular sodium-glucose linked cotransporter-2 (SGLT2) leads to glycosuria in both diabetic and non-diabetic settings. As a consequence of their ability to modulate tubuloglomerular feedback, SGLT2 inhibitors, like agents that block the renin-angiotensin system, reduce intraglomerular pressure and single nephron GFR, potentially affording renoprotection. To examine this further we administered the SGLT2 inhibitor, dapagliflozin, to 5/6 (subtotally) nephrectomised rats, a model of progressive chronic kidney disease (CKD) that like CKD in humans is characterised by single nephron hyperfiltration and intraglomerular hypertension and where angiotensin converting enzyme inhibitors and angiotensin receptor blockers are demonstrably beneficial. When compared with untreated rats, both sham surgery and 5/6 nephrectomised rats that had received dapagliflozin experienced substantial glycosuria. Nephrectomised rats developed hypertension, heavy proteinuria and declining GFR that was unaffected by the administration of dapagliflozin. Similarly, SGLT2 inhibition did not attenuate the extent of glomerulosclerosis, tubulointerstitial fibrosis or overexpression of the profibrotic cytokine, transforming growth factor-ß1 mRNA in the kidneys of 5/6 nephrectomised rats. While not precluding beneficial effects in the diabetic setting, these findings indicate that SGLT2 inhibition does not have renoprotective effects in this classical model of progressive non-diabetic CKD. PMID:26741142

  8. Seismic bearing

    NASA Astrophysics Data System (ADS)

    Power, Dennis

    2009-05-01

    Textron Systems (Textron) has been using geophones for target detection for many years. This sensing capability was utilized for detection and classification purposes only. Recently Textron has been evaluating multiaxis geophones to calculate bearings and track targets more specifically personnel. This capability will not only aid the system in locating personnel in bearing space or cartesian space but also enhance detection and reduce false alarms. Textron has been involved in the testing and evaluation of several sensors at multiple sites. One of the challenges of calculating seismic bearing is an adequate signal to noise ratio. The sensor signal to noise ratio is a function of sensor coupling to the ground, seismic propagation and range to target. The goals of testing at multiple sites are to gain a good understanding of the maximum and minimum ranges for bearing and detection and to exploit that information to tailor sensor system emplacement to achieve desired performance. Test sites include 10A Site Devens, MA, McKenna Airfield Ft. Benning, GA and Yuma Proving Ground Yuma, AZ. Geophone sensors evaluated include a 28 Hz triax spike, a 15 Hz triax spike and a hybrid triax spike consisting of a 10 Hz vertical geophone and two 28 Hz horizontal geophones. The algorithm uses raw seismic data to calculate the bearings. All evaluated sensors have triaxial geophone configuration mounted to a spike housing/fixture. The suite of sensors also compares various types of geophones to evaluate benefits in lower bandwidth. The data products of these tests include raw geophone signals, seismic features, seismic bearings, seismic detection and GPS position truth data. The analyses produce Probability of Detection vs range, bearing accuracy vs range, and seismic feature level vs range. These analysis products are compared across test sites and sensor types.

  9. Sodium Test

    MedlinePlus

    ... be limited. Home Visit Global Sites Search Help? Sodium Share this page: Was this page helpful? Also known as: Na Formal name: Sodium Related tests: Chloride , Bicarbonate , Potassium , Electrolytes , Osmolality , Basic ...

  10. Dietary Sodium Reduction Does Not Affect Circulating Glucose Concentrations in Fasting Children or Adults: Findings from a Systematic Review and Meta-Analysis1234

    PubMed Central

    Patel, Sheena M; Cobb, Paul; Saydah, Sharon; Zhang, Xuanping; de Jesus, Janet M; Cogswell, Mary E

    2015-01-01

    Background: Although evidence shows that reduced sodium intake lowers blood pressure, some studies suggest that sodium reduction may adversely affect insulin resistance and glucose tolerance. Objectives: The objectives were to assess the effects of sodium reduction on glucose tolerance, evaluate strengths and weaknesses of the relevant scientific literature, and provide direction for future research. Methods: We searched The Cochrane Library, MEDLINE, EMBASE, CINAHL, and Web of Science through August 2014. Both randomized and nonrandomized intervention trials were included in our meta-analyses. The effects of sodium reduction on glucose tolerance were evaluated in 37 articles, but because of a lack of comparable data, 8 trials were excluded from the meta-analyses. Results: Participants were 10–79 y old, either primarily healthy or with hypertension. In meta-analyses of 20 randomized, crossover trials (n = 504 participants) and 9 nonrandomized crossover trials (n = 337), circulating glucose concentrations of fasting participants were not affected by reduction in sodium intake. In contrast, in meta-analyses of 19 of the 20 randomized, crossover trials (n = 494), fasting insulin concentrations were 9.53 pmol/L higher (95% CI: 5.04, 14.02 pmol/L higher) with sodium reduction. In 9 nonrandomized trials (n = 337), fasting insulin did not differ with reduced sodium intake. Results differed little when the analyses were restricted to studies with a low risk of bias and duration of ≥7 d. Conclusions: This meta-analysis revealed no evidence that, in trials with a short intervention and large reductions in sodium, circulating glucose concentrations differed between groups. Recommendations for future studies include extending intervention durations, ensuring comparability of groups at baseline through randomization, and assessing sodium intakes relevant to population sodium reduction. In addition, analyses on other metabolic variables were limited because of the number of

  11. Sodium nitrate co-ingestion with protein does not augment postprandial muscle protein synthesis rates in older, type 2 diabetes patients.

    PubMed

    Kouw, Imre W K; Cermak, Naomi M; Burd, Nicholas A; Churchward-Venne, Tyler A; Senden, Joan M; Gijsen, Annemarie P; van Loon, Luc J C

    2016-08-01

    The age-related anabolic resistance to protein ingestion is suggested to be associated with impairments in insulin-mediated capillary recruitment and postprandial muscle tissue perfusion. The present study investigated whether dietary nitrate co-ingestion with protein improves muscle protein synthesis in older, type 2 diabetes patients. Twenty-four men with type 2 diabetes (72 ± 1 yr, 26.7 ± 1.4 m/kg(2) body mass index, 7.3 ± 0.4% HbA1C) received a primed continuous infusion of l-[ring-(2)H5]phenylalanine and l-[1-(13)C]leucine and ingested 20 g of intrinsically l-[1-(13)C]phenylalanine- and l-[1-(13)C]leucine-labeled protein with (PRONO3) or without (PRO) sodium nitrate (0.15 mmol/kg). Blood and muscle samples were collected to assess protein digestion and absorption kinetics and postprandial muscle protein synthesis rates. Upon protein ingestion, exogenous phenylalanine appearance rates increased in both groups (P < 0.001), resulting in 55 ± 2% and 53 ± 2% of dietary protein-derived amino acids becoming available in the circulation over the 5h postprandial period in the PRO and PRONO3 groups, respectively. Postprandial myofibrillar protein synthesis rates based on l-[ring-(2)H5]phenylalanine did not differ between groups (0.025 ± 0.004 and 0.021 ± 0.007%/h over 0-2 h and 0.032 ± 0.004 and 0.030 ± 0.003%/h over 2-5 h in PRO and PRONO3, respectively, P = 0.7). No differences in incorporation of dietary protein-derived l-[1-(13)C]phenylalanine into de novo myofibrillar protein were observed at 5 h (0.016 ± 0.002 and 0.014 ± 0.002 mole percent excess in PRO and PRONO3, respectively, P = 0.8). Dietary nitrate co-ingestion with protein does not modulate protein digestion and absorption kinetics, nor does it further increase postprandial muscle protein synthesis rates or the incorporation of dietary protein-derived amino acids into de novo myofibrillar protein in older, type 2 diabetes patients. PMID:27221118

  12. Alignment and operability analysis of a vertical sodium pump

    SciTech Connect

    Gupta, V.K.; Fair, C.E.

    1981-01-01

    With the objective of identifying important alignment features of pumps such as FFTF, HALLAM, EBR II, PNC, PHENIX, and CRBR, alignment of the vertical sodium pump for the Clinch River Breeder Reactor Plant (CRBRP) is investigated. The CRBRP pump includes a flexibly coupled pump shaft and motor shaft, two oil-film tilting-pad hydrodynamic radial bearings in the motor plus a vertical thrust bearing, and two sodium hydrostatic bearings straddling the double-suction centrifugal impeller in the pump.

  13. System for testing bearings

    NASA Astrophysics Data System (ADS)

    Gibson, John C.

    1993-07-01

    Disclosed here is a system for testing bearings wherein a pair of spaced bearings provides support for a shaft on which is mounted a bearing to be tested, this bearing being mounted in a bearing holder spaced from and in alignment with the pair of bearings. The bearing holder is provided with an annular collar positioned in an opening in the bearing holder for holding the bearing to be tested. A screw threaded through the bearing holder into engagement with the annular collar can be turned to force the collar radially out of alignment with the pair of bearings to apply a radial load to the bearing.

  14. Io's fast sodium: Implications for molecular and atomic atmospheric escape

    NASA Technical Reports Server (NTRS)

    Wilson, Jody K.; Schneider, Nicholas M.

    1994-01-01

    Recent observational evidence for sodium-bearing molecular ions in the Io plasma torus has strong implications for the nature of Io's atmosphere (Schneider et al. 1991). We use a Monte Carlo model offast-sodium production to analyze high-resolution ground-based images of sodium emission. We find the observations can be explained if a significant fraction of Io's exobase is molecular, possible including a sodium-bearing molecule, Total sodium loss rates from Io imply a collisionally thick atmosphere. Most of the images indicate significant slow-down of the corotating plasma near Io.

  15. CUSHIONED BEARING

    DOEpatents

    Rushing, F.C.

    1960-09-01

    A vibration damping device effective to dampen vibrations occurring at the several critical speeds encountered in the operation of a high-speed centrifuge is described. A self-centering bearing mechanism is used to protect both the centrifuge shaft and the damping mechanism. The damping mechanism comprises spaced-apant, movable, and stationary sleeve members arranged concentrically of a rotating shaft with a fluid maintained between the members. The movable sleeve member is connected to the shaft for radial movement therewith.

  16. Tooling Converts Stock Bearings To Custom Bearings

    NASA Technical Reports Server (NTRS)

    Fleenor, E. N., Jr.

    1983-01-01

    Technique for reworking stock bearings saves time and produces helicopter-rotor bearings ground more precisely. Split tapered ring at one end of threaded bolt expands to hold inside of inner race bearing assembly; nut, at other end of bolt, adjusts amount of spring tension. Piece of hardware grasps bearing firmly without interfering with grinding operation. Operation produces bearing of higher quality than commercially available bearings.

  17. Bending fatigue of electron-beam-welded foils. Application to a hydrodynamic air bearing in the Chrysler/DOE upgraded automotive gas tubine engine

    NASA Technical Reports Server (NTRS)

    Saltsman, J. F.; Halford, G. R.

    1984-01-01

    A hydrodynamic air bearing with a compliment surface is used in the gas generator of an upgraded automotive gas turbine engine. In the prototype design, the compliant surface is a thin foil spot welded at one end to the bearing cartridge. During operation, the foil failed along the line of spot welds which acted as a series of stress concentrators. Because of its higher degree of geometric uniformity, electron beam welding of the foil was selected as an alternative to spot welding. Room temperature bending fatigue tests were conducted to determine the fatigue resistance of the electron beam welded foils. Equations were determined relating cycles to crack initiation and cycles to failure to nominal total strain range. A scaling procedure is presented for estimating the reduction in cyclic life when the foil is at its normal operating temperature of 260 C (500 F).

  18. Measuring environmental stress in East Greenland polar bears, 1892-1927 and 1988-2009: what does hair cortisol tell us?

    PubMed

    Bechshøft, T Ø; Rigét, F F; Sonne, C; Letcher, R J; Muir, D C G; Novak, M A; Henchey, E; Meyer, J S; Eulaers, I; Jaspers, V L B; Eens, M; Covaci, A; Dietz, R

    2012-09-15

    Hair sampled from 96 East Greenland polar bears (Ursus maritimus) over the periods 1892-1927 and 1988-2009 was analyzed for cortisol as a proxy to investigate temporal patterns of environmental stress. Cortisol concentration was independent of sex and age, and was found at significantly higher (p<0.001) concentrations in historical hair samples (1892-1927; n=8) relative to recent ones (1988-2009; n=88). In addition, there was a linear time trend in cortisol concentration of the recent samples (p<0.01), with an annual decrease of 2.7%. The recent hair samples were also analyzed for major bioaccumulative, persistent organic pollutants (POPs). There were no obvious POP related time trends or correlations between hair cortisol and hair POP concentrations. Thus, polar bear hair appears to be a relatively poor indicator of the animal's general POP load in adipose tissue. However, further investigations are warranted to explore the reasons for the temporal decrease found in the bears' hair cortisol levels. PMID:22572112

  19. Sodium Oxybate

    MedlinePlus

    ... if you use or have ever used street drugs, or if you have overused prescription medications. Sodium oxybate may be harmful when taken by people other than the person for whom it was prescribed. Do not sell or give your sodium oxybate to anyone else; selling or sharing it is against the law. Store ...

  20. Alaskan brown bears, humans, and habituation

    USGS Publications Warehouse

    Smith, Thomas; Herrero, Stephen; DeBruyn, Terry D.

    2005-01-01

    We present a new paradigm for understanding habituation and the role it plays in brown bear (Ursus arctos) populations and interactions with humans in Alaska. We assert that 3 forms of habituation occur in Alaska: bear-to-bear, bear-to-human, and human-to-bear. We present data that supports our theory that bear density is an important factor influencing a bear’s overt reaction distance (ORD); that as bear density increases, overt reaction distance decreases, as does the likelihood of bear– human interactions. We maintain that the effects of bear-to-bear habituation are largely responsible for not only shaping bear aggregations but also for creating the relatively safe environment for bear viewing experienced at areas where there are high densities of brown bears. By promoting a better understanding of the forces that shape bear social interactions within populations and with humans that mingle with them, we can better manage human activities and minimize bear–human conflict.

  1. Measuring environmental stress in East Greenland polar bears, 1892–1927 and 1988–2009: what does hair cortisol tell us?

    PubMed Central

    TØ, Bechshøft; Rigét, FF; Sonne, C; Letcher, RJ; Muir, DCG; Novak, MA; Henchey, E; Meyer, JS; Eulaers; Jaspers, VLB; Eens, M; Covaci, A; Dietz, R

    2012-01-01

    Hair sampled from 96 East Greenland polar bears (Ursus maritimus) over the periods 1892–1927 and 1988–2009 was analyzed for cortisol as a proxy to investigate temporal patterns of environmental stress. Cortisol concentration was independent of sex and age, and was found at significantly higher (p < 0.001) concentrations in historical hair samples (1892–1927; n = 8) relative to recent ones (1988–2009; n = 88). In addition, there was a linear time trend in cortisol concentration of the recent samples (p < 0.01), with an annual decrease of 2.7 %. The recent hair samples were also analyzed for major bioaccumulative, persistent organic pollutants (POPs). There were no obvious POP related time trends or correlations between hair cortisol and hair POP concentrations. Thus, polar bear hair appears to be a relatively poor indicator of the animal’s general POP load in adipose tissue. However, further investigations are warranted to explore the reasons for the temporal decrease found in the bears’ hair cortisol levels. PMID:22572112

  2. Teflon lubrication of liquid oxygen turbopump bearings

    NASA Technical Reports Server (NTRS)

    Naerheim, Y.; Stocker, P. J.

    1989-01-01

    Ball bearings with glass fiber reinforced Teflon ball retainers from hot-fired liquid oxygen turbopumps were analyzed by X-ray photoelectron spectroscopy to determine the extent of Teflon transfer and/or chemical reaction at the bearing surface. No Teflon, but metal fluorides could be found on the metal surface. This indicates that Teflon decomposes and reacts with the bearing steel to form fluorides. Hence, Teflon does not appear to function directly as a lubricant under these operating conditions.

  3. Fluid lubricated bearing construction

    DOEpatents

    Dunning, John R.; Boorse, Henry A.; Boeker, Gilbert F.

    1976-01-01

    1. A fluid lubricated thrust bearing assembly comprising, in combination, a first bearing member having a plain bearing surface, a second bearing member having a bearing surface confronting the bearing surface of said first bearing member and provided with at least one spiral groove extending inwardly from the periphery of said second bearing member, one of said bearing members having an axial fluid-tight well, a source of fluid lubricant adjacent to the periphery of said second bearing member, and means for relatively rotating said bearing members to cause said lubricant to be drawn through said groove and to flow between said bearing surfaces, whereby a sufficient pressure is built up between said bearing surfaces and in said well to tend to separate said bearing surfaces.

  4. Cryogenic turbopump bearing materials

    NASA Technical Reports Server (NTRS)

    Bhat, Biliyar N.

    1989-01-01

    Materials used for modern cryogenic turbopump bearings must withstand extreme conditions of loads and speeds under marginal lubrication. Naturally, these extreme conditions tend to limit the bearing life. It is possible to significantly improve the life of these bearings, however, by improving the fatigue and wear resistance of bearing alloys, and improving the strength, liquid oxygen compatibility and lubricating ability of the bearing cage materials. Improved cooling will also help to keep the bearing temperatures low and hence prolong the bearing life.

  5. Cluster ion beam profiling of organics by secondary ion mass spectrometry--does sodium affect the molecular ion intensity at interfaces?

    PubMed

    Green, Felicia M; Gilmore, Ian S; Seah, Martin P

    2008-12-01

    The use of cluster ion beam sputtering for depth profiling organic materials is of growing technological importance and is a very active area of research. At the 44th IUVSTA Workshop on "Sputtering and Ion Emission by Cluster Ion Beams", recent results were presented of a cluster ion beam depth profile of a thin organic molecular layer on a silicon wafer substrate. Those data showed that the intensity of molecular secondary ions is observed to increase at the interface and this was explained in terms of the higher stopping power in the substrate and a consequently higher sputtering yield and even higher secondary ion molecular sputtering yield. An alternative hypothesis was postulated in the workshop discussion which may be paraphrased as: "under primary ion bombardment of an organic layer, mobile ions such as sodium may migrate to the interface with the inorganic substrate and this enhancement of the sodium concentration increases the ionisation probability, so increasing the molecular ion yield observed at the interface". It is important to understand if measurement artefacts occur at interfaces for quantification as these are of great technological relevance - for example, the concentration of drug in a drug delivery system. Here, we evaluate the above hypothesis using a sample that exhibits regions of high and low sodium concentration at both the organic surface and the interface with the silicon wafer substrate. There is no evidence to support the hypothesis that the probability of molecular secondary ion ionisation is related to the sodium concentration at these levels. PMID:19039819

  6. 21 CFR 173.385 - Sodium methyl sulfate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... subsequent treatment with sodium bicarbonate. (b) It does not exceed 0.1 percent by weight of the pectin. ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sodium methyl sulfate. 173.385 Section 173.385... Sodium methyl sulfate. Sodium methyl sulfate may be present in pectin in accordance with the...

  7. 21 CFR 173.385 - Sodium methyl sulfate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... pectin by sulfuric acid and methyl alcohol and subsequent treatment with sodium bicarbonate. (b) It does... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Sodium methyl sulfate. 173.385 Section 173.385... CONSUMPTION Specific Usage Additives § 173.385 Sodium methyl sulfate. Sodium methyl sulfate may be present...

  8. 21 CFR 173.385 - Sodium methyl sulfate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... sulfuric acid and methyl alcohol and subsequent treatment with sodium bicarbonate. (b) It does not exceed 0... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium methyl sulfate. 173.385 Section 173.385 Food... Specific Usage Additives § 173.385 Sodium methyl sulfate. Sodium methyl sulfate may be present in pectin...

  9. 21 CFR 173.385 - Sodium methyl sulfate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... pectin by sulfuric acid and methyl alcohol and subsequent treatment with sodium bicarbonate. (b) It does... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Sodium methyl sulfate. 173.385 Section 173.385... CONSUMPTION Specific Usage Additives § 173.385 Sodium methyl sulfate. Sodium methyl sulfate may be present...

  10. Modeling sulfate reduction in methane hydrate-bearing continental margin sediments: Does a sulfate-methane transition require anaerobic oxidation of methane?

    USGS Publications Warehouse

    Malinverno, A.; Pohlman, J.W.

    2011-01-01

    The sulfate-methane transition (SMT), a biogeochemical zone where sulfate and methane are metabolized, is commonly observed at shallow depths (1-30 mbsf) in methane-bearing marine sediments. Two processes consume sulfate at and above the SMT, anaerobic oxidation of methane (AOM) and organoclastic sulfate reduction (OSR). Differentiating the relative contribution of each process is critical to estimate methane flux into the SMT, which, in turn, is necessary to predict deeper occurrences of gas hydrates in continental margin sediments. To evaluate the relative importance of these two sulfate reduction pathways, we developed a diagenetic model to compute the pore water concentrations of sulfate, methane, and dissolved inorganic carbon (DIC). By separately tracking DIC containing 12C and 13C, the model also computes ??13C-DIC values. The model reproduces common observations from methane-rich sediments: a well-defined SMT with no methane above and no sulfate below and a ??13C-DIC minimum at the SMT. The model also highlights the role of upward diffusing 13C-enriched DIC in contributing to the carbon isotope mass balance of DIC. A combination of OSR and AOM, each consuming similar amounts of sulfate, matches observations from Site U1325 (Integrated Ocean Drilling Program Expedition 311, northern Cascadia margin). Without AOM, methane diffuses above the SMT, which contradicts existing field data. The modeling results are generalized with a dimensional analysis to the range of SMT depths and sedimentation rates typical of continental margins. The modeling shows that AOM must be active to establish an SMT wherein methane is quantitatively consumed and the ??13C-DIC minimum occurs. The presence of an SMT generally requires active AOM. Copyright 2011 by the American Geophysical Union.

  11. Acifluorfen, sodium

    Integrated Risk Information System (IRIS)

    Acifluorfen , sodium ; CASRN 62476 - 59 - 9 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcino

  12. Sodium diethyldithiocarbamate

    Integrated Risk Information System (IRIS)

    Sodium diethyldithiocarbamate ; CASRN 148 - 18 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Non

  13. Sodium fluoroacetate

    Integrated Risk Information System (IRIS)

    Sodium fluoroacetate ; CASRN 62 - 74 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogen

  14. Sodium azide

    Integrated Risk Information System (IRIS)

    Sodium azide ; CASRN 26628 - 22 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Ef

  15. Sodium cyanide

    Integrated Risk Information System (IRIS)

    Jump to main content . Integrated Risk Information System Recent Additions | Contact Us Search : All EPA IRIS • You are here : EPA Home • Research • Environmental Assessment • IRIS • IRIS Summaries Redirect Page As of September 28 , 2010 , the assessment summary for sodium cyanide is included in the

  16. Molecular phylogeny and SNP variation of polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus) derived from genome sequences.

    PubMed

    Cronin, Matthew A; Rincon, Gonzalo; Meredith, Robert W; MacNeil, Michael D; Islas-Trejo, Alma; Cánovas, Angela; Medrano, Juan F

    2014-01-01

    We assessed the relationships of polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus) with high throughput genomic sequencing data with an average coverage of 25× for each species. A total of 1.4 billion 100-bp paired-end reads were assembled using the polar bear and annotated giant panda (Ailuropoda melanoleuca) genome sequences as references. We identified 13.8 million single nucleotide polymorphisms (SNP) in the 3 species aligned to the polar bear genome. These data indicate that polar bears and brown bears share more SNP with each other than either does with black bears. Concatenation and coalescence-based analysis of consensus sequences of approximately 1 million base pairs of ultraconserved elements in the nuclear genome resulted in a phylogeny with black bears as the sister group to brown and polar bears, and all brown bears are in a separate clade from polar bears. Genotypes for 162 SNP loci of 336 bears from Alaska and Montana showed that the species are genetically differentiated and there is geographic population structure of brown and black bears but not polar bears. PMID:24477675

  17. Zinc absorption from zinc oxide, zinc sulfate, zinc oxide + EDTA, or sodium-zinc EDTA does not differ when added as fortificants to maize tortillas.

    PubMed

    Hotz, Christine; DeHaene, Jessica; Woodhouse, Leslie R; Villalpando, Salvador; Rivera, Juan A; King, Janet C

    2005-05-01

    The fortification of staple foods with zinc may play an important role in achieving adequate zinc intakes in countries at risk of zinc deficiency. However, little is known about the relative bioavailability of different zinc compounds that may be used in food fortification. The objective of this study was to measure and compare fractional zinc absorption from a test meal that included a maize tortilla fortified with zinc oxide, zinc sulfate, zinc oxide + EDTA, or sodium-zinc EDTA. A double isotopic tracer ratio method ((67)Zn as oral tracer and (70)Zn as intravenous tracer) was used to estimate zinc absorption in 42 Mexican women living in a periurban community of Puebla State, Mexico. The test meal consisted of maize tortillas, yellow beans, chili sauce, and milk with instant coffee; it contained 3.3 mg zinc and had a phytate:zinc molar ratio of 17. Fractional zinc absorption did not differ significantly between the test groups (ANOVA; P > 0.05). Percent absorptions were (mean +/- SD) zinc oxide, 10.8 +/- 0.9; zinc sulfate, 10.0 +/- 0.02; zinc oxide + EDTA, 12.7 +/- 1.5; and sodium-zinc EDTA, 11.1 +/- 0.7. We conclude that there was no difference in zinc absorption from ZnO and ZnSO(4) when added as fortificants to maize tortillas and consumed with beans and milk. The addition of EDTA with zinc oxide or the use of prechelated sodium-zinc EDTA as fortificants did not result in higher zinc absorption from the test meal. PMID:15867288

  18. Restoration of bearings

    NASA Technical Reports Server (NTRS)

    Parker, R. J.; Zaretsky, E. V.; Hanau, H.

    1977-01-01

    Process consisting of grinding raceways to oversize but original quality condition and installing new oversize balls or bearings restores wornout ball and roller bearings to original quality, thereby doubling their operating life. Evaluations reveal process results in restoration of 90% of replaced bearings at less than 50% of new-bearing costs.

  19. Passive magnetic bearing configurations

    DOEpatents

    Post, Richard F.

    2011-01-25

    A journal bearing provides vertical and radial stability to a rotor of a passive magnetic bearing system when the rotor is not rotating and when it is rotating. In the passive magnetic bearing system, the rotor has a vertical axis of rotation. Without the journal bearing, the rotor is vertically and radially unstable when stationary, and is vertically stable and radially unstable when rotating.

  20. Rolling-Element Bearings

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.; Anderson, W. J.

    1983-01-01

    Rolling element bearings are a precision, yet simple, machine element of great utility. A brief history of rolling element bearings is reviewed and the type of rolling element bearings, their geometry and kinematics, as well as the materials they are made from and the manufacturing processes they involve are described. Unloaded and unlubricated rolling element bearings, loaded but unlubricated rolling element bearings and loaded and lubricated rolling element bearings are considered. The recognition and understanding of elastohydrodynamic lubrication covered, represents one of the major development in rolling element bearings.

  1. Test Your Sodium Smarts

    MedlinePlus

    ... You may be surprised to learn how much sodium is in many foods. Sodium, including sodium chloride ... foods with little or no salt. Test your sodium smarts by answering these 10 questions about which ...

  2. Low sodium level

    MedlinePlus

    Low sodium level is a condition in which the amount of sodium (salt) in the blood is lower ... and this causes many of the symptoms of low sodium. With low sodium level (hyponatremia), the imbalance of ...

  3. Introduction to ball bearings

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.; Dowson, D.

    1981-01-01

    The purpose of a ball bearing is to provide a relative positioning and rotational freedom while transmitting a load between two structures, usually a shaft and a housing. For high rotational speeds (e.g., in gyroscope ball bearings) the purpose can be expanded to include rotational freedom with practically no wear in the bearing. This condition can be achieved by separating the bearing parts with a coherent film of fluid known as an elastohydrodynamic film. This film can be maintained not only when the bearing carries the load on a shaft, but also when the bearing is preloaded to position the shaft to within micro- or nano-inch accuracy and stability. Background information on ball bearings is provided, different types of ball bearings and their geometry and kinematics are defined, bearing materials, manufacturing processes, and separators are discussed. It is assumed, for the purposes of analysis, that the bearing carries no load.

  4. High efficiency magnetic bearings

    NASA Technical Reports Server (NTRS)

    Studer, Philip A.; Jayaraman, Chaitanya P.; Anand, Davinder K.; Kirk, James A.

    1993-01-01

    Research activities concerning high efficiency permanent magnet plus electromagnet (PM/EM) pancake magnetic bearings at the University of Maryland are reported. A description of the construction and working of the magnetic bearing is provided. Next, parameters needed to describe the bearing are explained. Then, methods developed for the design and testing of magnetic bearings are summarized. Finally, a new magnetic bearing which allows active torque control in the off axes directions is discussed.

  5. Protocol: does sodium nitrite administration reduce ischaemia-reperfusion injury in patients presenting with acute ST segment elevation myocardial infarction? Nitrites in acute myocardial infarction (NIAMI)

    PubMed Central

    2013-01-01

    Background Whilst advances in reperfusion therapies have reduced early mortality from acute myocardial infarction, heart failure remains a common complication, and may develop very early or long after the acute event. Reperfusion itself leads to further tissue damage, a process described as ischaemia-reperfusion-injury (IRI), which contributes up to 50% of the final infarct size. In experimental models nitrite administration potently protects against IRI in several organs, including the heart. In the current study we investigate whether intravenous sodium nitrite administration immediately prior to percutaneous coronary intervention (PCI) in patients with acute ST segment elevation myocardial infarction will reduce myocardial infarct size. This is a phase II, randomised, placebo-controlled, double-blinded and multicentre trial. Methods and outcomes The aim of this trial is to determine whether a 5 minute systemic injection of sodium nitrite, administered immediately before opening of the infarct related artery, results in significant reduction of IRI in patients with first acute ST elevation myocardial infarction (MI). The primary clinical end point is the difference in infarct size between sodium nitrite and placebo groups measured using cardiovascular magnetic resonance imaging (CMR) performed at 6–8 days following the AMI and corrected for area at risk (AAR) using the endocardial surface area technique. Secondary end points include (i) plasma creatine kinase and Troponin I measured in blood samples taken pre-injection of the study medication and over the following 72 hours; (ii) infarct size at six months; (iii) Infarct size corrected for AAR measured at 6–8 days using T2 weighted triple inversion recovery (T2-W SPAIR or STIR) CMR imaging; (iv) Left ventricular (LV) ejection fraction measured by CMR at 6–8 days and six months following injection of the study medication; and (v) LV end systolic volume index at 6–8 days and six months. Funding, ethics and

  6. Low sodium diet (image)

    MedlinePlus

    ... for you. Look for these words on labels: low-sodium, sodium-free, no salt added, sodium-reduced, or ... for you. Look for these words on labels: low-sodium, sodium-free, no salt added, sodium-reduced, or ...

  7. Closure Welding of Plutonium Bearing Storage Containers

    SciTech Connect

    Cannell, G.R.

    2002-02-28

    A key element in the Department of Energy (DOE) strategy for the stabilization, packaging and storage of plutonium-bearing materials involves closure welding of DOE-STD-3013 Outer Containers (3013 container). The 3013 container provides the primary barrier and pressure boundary preventing release of plutonium-bearing materials to the environment. The final closure (closure weld) of the 3013 container must be leaktight, structurally sound and meet DOE STD 3013 specified criteria. This paper focuses on the development, qualification and demonstration of the welding process for the closure welding of Hanford PFP 3013 outer containers.

  8. Conservation of the Yellowstone grizzly bear

    USGS Publications Warehouse

    Mattson, David J.; Reid, Matthew M.

    1991-01-01

    We review literature relevant to the conservation of Yellowstone's grizzly bear population and appraise the bear's long-term viability. We conclude that the population is isolated and vulnerable to epidemic perturbation and that the carrying capacity of the habitat is likely to shift downward under conditions of climate change. Viability analyses based on the assumption that future habitats will closely resemble those existing at present have limited applicability; more information is needed on the autecology of important bear foods and on the implications of landscape-scale changes for bear population dynamics. Optimism over prospects of long-term persistence for Yellowstone's grizzly bears does not seem to be warranted and management of this population should be conservative and not unduly swayed on short-term positive trends.

  9. Chronic Vitamin C Deficiency Promotes Redox Imbalance in the Brain but Does Not Alter Sodium-Dependent Vitamin C Transporter 2 Expression

    PubMed Central

    Paidi, Maya D.; Schjoldager, Janne G.; Lykkesfeldt, Jens; Tveden-Nyborg, Pernille

    2014-01-01

    Vitamin C (VitC) has several roles in the brain acting both as a specific and non-specific antioxidant. The brain upholds a very high VitC concentration and is able to preferentially retain VitC even during deficiency. The accumulation of brain VitC levels much higher than in blood is primarily achieved by the sodium dependent VitC transporter (SVCT2). This study investigated the effects of chronic pre-and postnatal VitC deficiency as well as the effects of postnatal VitC repletion, on brain SVCT2 expression and markers of oxidative stress in young guinea pigs. Biochemical analyses demonstrated significantly decreased total VitC and an increased percentage of dehydroascorbic acid, as well as increased lipid oxidation (malondialdehyde), in the brains of VitC deficient animals (p < 0.0001) compared to controls. VitC repleted animals were not significantly different from controls. No significant changes were detected in either gene or protein expression of SVCT2 between groups or brain regions. In conclusion, chronic pre-and postnatal VitC deficiency increased brain redox imbalance but did not increase SVCT2 expression. Our findings show potential implications for VitC deficiency induced negative effects of redox imbalance in the brain and provide novel insight to the regulation of VitC in the brain during deficiency. PMID:24787032

  10. Mechanical spin bearings

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (Inventor)

    1998-01-01

    A spin bearing assembly including, a pair of mutually opposing complementary bearing support members having mutually spaced apart bearing support surfaces which may be, for example, bearing races and a set of spin bearings located therebetween. Each spin bearing includes a pair of end faces, a central rotational axis passing through the end faces, a waist region substantially mid-way between the end faces and having a first thickness dimension, and discrete side surface regions located between the waist region and the end faces and having a second thickness dimension different from the first thickness dimension of the waist region and wherein the side surface regions further have respective curvilinear contact surfaces adapted to provide a plurality of bearing contact points on the bearing support members.

  11. Axial Halbach Magnetic Bearings

    NASA Technical Reports Server (NTRS)

    Eichenberg, Dennis J.; Gallo, Christopher A.; Thompson, William K.

    2008-01-01

    Axial Halbach magnetic bearings have been investigated as part of an effort to develop increasingly reliable noncontact bearings for future high-speed rotary machines that may be used in such applications as aircraft, industrial, and land-vehicle power systems and in some medical and scientific instrumentation systems. Axial Halbach magnetic bearings are passive in the sense that unlike most other magnetic bearings that have been developed in recent years, they effect stable magnetic levitation without need for complex active control.

  12. Supertough Stainless Bearing Steel

    NASA Technical Reports Server (NTRS)

    Olson, Gregory B.

    1995-01-01

    Composition and processing of supertough stainless bearing steel designed with help of computer-aided thermodynamic modeling. Fracture toughness and hardness of steel exceeds those of other bearing steels like 440C stainless bearing steel. Developed for service in fuel and oxidizer turbopumps on Space Shuttle main engine. Because of strength and toughness, also proves useful in other applications like gears and surgical knives.

  13. 1-Way Bearing

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (Inventor)

    2003-01-01

    A one-way bearing is provided having sprags and rolling bearings both disposed between an inner and an outer race. The sprags may comprise three-dimensional sprags for preventing rotation in a non-preferential direction. The roll- ing bearings may comprise thrust rollers for transmitting axial, tilt, and radial loads between the inner and outer races.

  14. 21 CFR 184.1769a - Sodium metasilicate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sodium metasilicate. 184.1769a Section 184.1769a... GRAS § 184.1769a Sodium metasilicate. (a) Sodium metasilicate (CAS Reg. No. 6834-92-0) is a strongly alkaline white powder. It does not occur naturally but rather is synthesized by melting sand with...

  15. The Sodium Process Facility at Argonne National Laboratory-West

    SciTech Connect

    Michelbacher, J.A.; Henslee, S.P. McDermott, M.D.; Price, J.R.; Rosenberg, K.E.; Wells, P.B.

    1998-07-01

    Argonne National Laboratory-West (ANL-W) has approximately 680,000 liters of raw sodium stored in facilities on site. As mandated by the State of Idaho and the US Department of Energy (DOE), this sodium must be transformed into a stable condition for land disposal. To comply with this mandate, ANL-W designed and built the Sodium Process Facility (SPF) for the processing of this sodium into a dry, sodium carbonate powder. The major portion of the sodium stored at ANL-W is radioactively contaminated. The sodium will be processed in three separate and distinct campaigns: the 290,000 liters of Fermi-1 primary sodium, the 50,000 liters of the Experimental Breeder Reactor-II (EBR-II) secondary sodium, and the 330,000 liters of the EBR-II primary sodium. The Fermi-1 and the EBR-II secondary sodium contain only low-level of radiation, while the EBR-II primary sodium has radiation levels up to 0.5 mSv (50 mrem) per hour at 1 meter. The EBR-II primary sodium will be processed last, allowing the operating experience to be gained with the less radioactive sodium prior to reacting the most radioactive sodium. The sodium carbonate will be disposed of in 270 liter barrels, four to a pallet. These barrels are square in cross-section, allowing for maximum utilization of the space on a pallet, minimizing the required landfill space required for disposal.

  16. Bearings working group

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The service life of the Space Shuttle Main Engine (SSME) turbomachinery bearings was a predominant factor in engine durability and maintenance problems. Recent data has indicated that bearing life is about one order of magnitude lower than the goal of seven and one-half hours particularly those in the High Pressure Oxidizer Turbopump (HPOTP). Bearing technology, primarily cryogenic turbomachinery bearing technology, is expanded by exploring the life and performance effects of design changes; design concept changes; materials changes; manufacturing technique changes; and lubrication system changes. Each variation is assessed against the current bearing design in full scale cryogenic tests.

  17. Cryogenic Hybrid Magnetic Bearing

    NASA Technical Reports Server (NTRS)

    Meeks, Crawford R.; Dirusso, Eliseo; Brown, Gerald V.

    1994-01-01

    Cryogenic hybrid magnetic bearing is example of class of magnetic bearings in which permanent magnets and electromagnets used to suspend shafts. Electromagnets provide active control of position of shaft. Bearing operates at temperatures from -320 degrees F (-196 degrees C) to 650 degrees F (343 degrees C); designed for possible use in rocket-engine turbopumps, where effects of cryogenic environment and fluid severely limit lubrication of conventional ball bearings. This and similar bearings also suitable for terrestrial rotating machinery; for example, gas-turbine engines, high-vacuum pumps, canned pumps, precise gimbals that suspend sensors, and pumps that handle corrosive or gritty fluids.

  18. Low sodium level

    MedlinePlus

    Low sodium level is a condition in which the amount of sodium (salt) in the blood is lower than normal. The ... Sodium is found mostly in the body fluids outside the cells. It is very important for maintaining ...

  19. Variation of sodium on Mercury with solar radiation pressure

    NASA Astrophysics Data System (ADS)

    Potter, A. E.; Morgan, T. H.

    1987-09-01

    Sodiums atoms in the atmosphere of Mercury can be accelerated by solar radiation pressure, and several authors have suggested that radiation pressure could sweep sodium off the planet. As a consequence, the sodium abundance might be expected to decrease as the radiation pressure increases. The authors have measured the average sodium abundance over a range of solar radiation pressures and found that the sodium abundance does decrease with increasing radiation pressure. Possible explanations for the observed variation are (1) that radiation pressure sweeps away transient high-velocity sodium atoms generated upon meteoric material impacts, thus reducing the supply rate of sodium, or (2) that the accommodation coefficient of sodium for surface interactions is less than unity, so that radiation pressure can effectively push sodium to the dark side of the planet, where it cannot be detected by scattered sunlight.

  20. Bearings: Technology and needs

    NASA Technical Reports Server (NTRS)

    Anderson, W. J.

    1982-01-01

    A brief status report on bearing technology and present and near-term future problems that warrant research support is presented. For rolling element bearings a material with improved fracture toughness, life data in the low Lambda region, a comprehensive failure theory verified by life data and incorporated into dynamic analyses, and an improved corrosion resistant alloy are perceived as important needs. For hydrodynamic bearings better definition of cavitation boundaries and pressure distributions for squeeze film dampers, and geometry optimization for minimum power loss in turbulent film bearings are needed. For gas film bearings, foil bearing geometries that form more nearly optimum film shapes for maximum load capacity, and more effective surface protective coatings for high temperature operation are needed.

  1. Atmospheric Dispersion of Sodium Aerosol due to a Sodium Leak in a Fast Breeder Reactor Complex

    NASA Astrophysics Data System (ADS)

    Punitha, G.; Sudha, A. Jasmin; Kasinathan, N.; Rajan, M.

    Liquid sodium at high temperatures (470 K to 825 K) is used as the primary and secondary coolant in Liquid Metal cooled Fast Breeder Reactors (LMFBR). In the event of a postulated sodium leak in the Steam Generator Building (SGB) of a LMFBR, sodium readily combusts in the ambient air, especially at temperatures above 523 K. Intense sodium fire results and sodium oxide fumes are released as sodium aerosols. Sodium oxides are readily converted to sodium hydroxide in air due to the presence of moisture in it. Hence, sodium aerosols are invariably in the form of particulate sodium hydroxide. These aerosols damage not only the equipment and instruments due to their corrosive nature but also pose health hazard to humans. Hence, it is essential to estimate the concentration of sodium aerosols within the plant boundary for a sodium leak event. The Gaussian Plume Dispersion Model can obtain the atmospheric dispersion of sodium aerosols in an open terrain. However, this model does not give accurate results for dispersion in spaces close to the point of release and with buildings in between. The velocity field due to the wind is altered to a large extent by the intervening buildings and structures. Therefore, a detailed 3-D estimation of the velocity field and concentration has to be obtained through rigorous computational fluid dynamics (CFD) approach. PHOENICS code has been employed to determine concentration of sodium aerosols at various distances from the point of release. The dispersion studies have been carried out for the release of sodium aerosols at different elevations from the ground and for different wind directions.

  2. Effects of bearing deadbands on bearing loads and rotor stability

    NASA Technical Reports Server (NTRS)

    1984-01-01

    A generic model of a turbopump, simplified to bring out these effects is examined. This model demonstrates that bearing deadbands which are of the same order of magnitude or larger than the center-of-mass offset of a rotor due to mass imbalances cause significantly different dynamic behavior than would be expected of a linear, dynamical system. This fundamentally nonlinear behavior yields altered stability characteristics and altered bearing loading tendencies. It is shown that side forces can enhance system stability in the small, i.e., as long as the mass imbalance does not exceed some thresholds value or as long as no large, impulsive disturbances cause the motion to depart significantly from the region of stability. Limit cycles are investigated in this report and techniques for determining these limit cycles are developed. These limit cycles are the major source of bearing loading and appear in both synchronous and nonsynchronous forms. The synchronous limit cycles are driven by rotor imbalances. The nonsynchronous limit cycles (also called subsynchronous whirls) are self-excited and are the sources of instability.

  3. Bear Spray Safety Program

    USGS Publications Warehouse

    Blome, C.D.; Kuzniar, R.L.

    2009-01-01

    A bear spray safety program for the U.S. Geological Survey (USGS) was officially initiated by the Firearms Safety Committee to address accident prevention and to promote personnel training in bear spray and its transportation, storage, and use for defense against wild animals. Used as part of a system including firearms, or used alone for those who choose not to carry a firearm, bear spray is recognized as an effective tool that can prevent injury in a wild animal attack.

  4. Monitoring grizzly bear population trends

    USGS Publications Warehouse

    Eberhardt, L.L.; Knight, R.R.; Blanchard, B.M.

    1986-01-01

    A simple different equation model was developed to provide additional perspective on observed mortality and trend data on Yellowstone grizzly bears (Ursus arctos horribilis). Records of mortalities of adult females from 1959 to 1985 were utilized, in conjunction with data on females with cubs. The overall downward trend of observed numbers of females with cubs generally agrees with the model calculations but does not adequately reflect mortality from 1970 to 1974. The model may be useful in developing a composite index of population trend.

  5. Diclofenac sodium.

    PubMed

    Small, R E

    1989-08-01

    The pharmacology, pharmacokinetics, clinical efficacy, adverse effects, and dosage of diclofenac sodium are reviewed. Diclofenac, the first nonsteroidal anti-inflammatory agent (NSAID) to be approved that is a phenylacetic acid derivative, competes with arachidonic acid for binding to cyclo-oxygenase, resulting in decreased formation of prostaglandins. The drug has both analgesic and antipyretic activities. Diclofenac is efficiently absorbed from the gastrointestinal tract; peak plasma concentrations occur 1.5 to 2.0 hours after ingestion in fasting subjects. Even though diclofenac has a relatively short elimination half-life in plasma (1.5 hours), it persists in synovial fluid. The drug is metabolized in the liver and is eliminated by urinary and biliary excretion. In clinical trials, diclofenac was as effective as aspirin, diflunisal, indomethacin, sulindac, ibuprofen, ketoprofen, and naproxen in improving function and reducing pain in patients with rheumatoid arthritis. For treatment of osteoarthritis, diclofenac was equivalent in efficacy to aspirin, diflunisal, indomethacin, sulindac, ibuprofen, ketoprofen, naproxen, flurbiprofen, mefenamic acid, and piroxicam. Diclofenac was as effective as indomethacin or sulindac in treating ankylosing spondylitis. The most frequent adverse effects reported for diclofenac were gastrointestinal, but these effects were fewer and less serious than occurred with aspirin or indomethacin; in addition, diclofenac caused fewer central nervous system reactions than indomethacin. Diclofenac is administered in divided doses with meals. The recommended total daily dosage is 100 to 150 mg (osteoarthritis and ankylosing spondylitis) or 150 to 200 mg (rheumatoid arthritis). Diclofenac is effective, but no more so than other NSAIDs. It is structurally distinct and offers another choice in the treatment of rheumatological conditions. PMID:2670397

  6. Bearing restoration by grinding

    NASA Technical Reports Server (NTRS)

    Hanau, H.; Parker, R. J.; Zaretsky, E. V.; Chen, S. M.; Bull, H. L.

    1976-01-01

    A joint program was undertaken by the NASA Lewis Research Center and the Army Aviation Systems Command to restore by grinding those rolling-element bearings which are currently being discarded at aircraft engine and transmission overhaul. Three bearing types were selected from the UH-1 helicopter engine (T-53) and transmission for the pilot program. No bearing failures occurred related to the restoration by grinding process. The risk and cost of a bearing restoration by grinding programs was analyzed. A microeconomic impact analysis was performed.

  7. Extending bearing life

    SciTech Connect

    Boyer, D.

    1997-08-01

    Long-term bearing operation cannot be achieved unless proper handling, storage, installation, and maintenance procedures are followed. These factors can shorten--sometimes drastically--expected bearing service life. Failures are generally related to improper lubrication or installation and induced conditions. Most major bearing manufacturers offer technical assistance in inspection, evaluation, and reporting on bearings which have failed in service. Actual percentages associated with each failure category vary, depending on the source, but generally they are 70% from lubrication and installation, 20% from induced factors, and 10% from reaching their fatigue limit or design life. The paper describes lubricant-related failures and procedures for the correct handling, storage, installation, and maintenance.

  8. Sodium blood test

    MedlinePlus

    ... foods. The most common form of sodium is sodium chloride, which is table salt. This test is usually done as part of an electrolyte or basic metabolic panel blood test . Your blood sodium level represents a balance between the sodium and ...

  9. External Coulomb-Friction Damping For Hydrostatic Bearings

    NASA Technical Reports Server (NTRS)

    Buckmann, Paul S.

    1992-01-01

    External friction device damps vibrations of shaft and hydrostatic ring bearing in which it turns. Does not rely on wear-prone facing surfaces. Hydrostatic bearing ring clamped in radially flexing support by side plates clamped against radial surfaces by spring-loaded bolts. Plates provide friction against radial motions of shaft.

  10. Amended safety assessment of sodium picramate and picramic acid.

    PubMed

    Becker, Lillian C; Bergfeld, Wilma F; Belsito, Donald V; Klaassen, Curtis D; Marks, James G; Shank, Ronald C; Slaga, Thomas J; Snyder, Paul W; Alan Andersen, F

    2009-01-01

    Sodium picramate is the sodium salt of picramic acid, a substituted phenolic compound. Sodium picramate and picramic acid function as hair colorants; they are reportedly used in 31 and 3 hair-dye products, respectively. No concentration-of-use data were available for sodium picramate, but picramic acid was reported to be used at 0.6%. The Cosmetic Ingredient Review Expert Panel recognized that adding picramic acid to a hair-dye formulation likely results in formation of a salt such as sodium picramate, which suggested that safety test data for one ingredient would be applicable to the other. Hair dyes containing these ingredients bear a caution statement and patch test instructions for determining whether the product causes skin irritation. The panel finds that the available data support the safety of these colorants in hair dyes and expects that sodium picramate would be used at concentrations comparable to those reported for picramic acid. PMID:20086193

  11. Passive Magnetic Bearing

    NASA Technical Reports Server (NTRS)

    Studer, P. A.

    1983-01-01

    Magnetic bearing for limited rotation devices requires no feedback control system to sense and correct shaft position. Passive Magnetic Torsion Bearing requires no power supply and has no rubbing parts. Torsion wire restrains against axial instability. Magnetic flux geometry chosen to assure lateral stability with radial restoring force that maintains alignment.

  12. Bearing servicing tool

    NASA Technical Reports Server (NTRS)

    Boyce, Rex A. (Inventor)

    1992-01-01

    A tool for removing and/or replacing bearings in situ is presented. The tool is comprised of a brace having a first end adapted to engage a first end of the bearing housing, and a second end adapted to engage a second end of the bearing housing. If the two ends of the bearing housing are different in configuration, then the respective ends of the brace are configured accordingly. An elongate guide member integral with the brace has two parts, each projecting endwise from a respective end of the brace. A removable pressure plate can be mounted on either part of the guide member for longitudinal movement therealong and has first and second ends of different configurations adapted to engage the first and second ends of the bearing. A threaded-type drive is cooperative between the guide and the pressure plate to move the pressure plate longitudinally along the guide and apply a force to the bearing, either to remove the bearing from its housing, or to emplace a new bearing in the housing.

  13. Bearing fatigue investigation 3

    NASA Technical Reports Server (NTRS)

    Nahm, A. H.; Bamberger, E. N.; Signer, H. R.

    1982-01-01

    The operating characteristics of large diameter rolling-element bearings in the ultra high speed regimes expected in advanced turbine engines for high performance aircraft were investigated. A high temperature lubricant, DuPont Krytox 143 AC, was evaluated at bearing speeds to 3 million DN. Compared to the results of earlier, similar tests using a MIL-L-23699 (Type II) lubricant, bearings lubricated with the high density Krytox fluid showed significantly higher power requirements. Additionally, short bearing lives were observed when this fluid was used with AISI M50 bearings in an air atmosphere. The primary mode of failure was corrosion initiated surface distress (fatigue) on the raceways. The potential of a case-carburized bearing to sustain a combination of high-tangential and hertzian stresses without experiencing race fracture was also investigated. Limited full scale bearing tests of a 120 mm bore ball bearing at a speed of 25,000 rpm (3 million DN) indicated that a carburized material could sustain spalling fatigue without subsequent propagation to fracture. Planned life tests of the carburized material had to be aborted, however, because of apparent processing-induced material defects.

  14. Cylindrical bearing analysis

    NASA Technical Reports Server (NTRS)

    Kleckner, R. J.; Pirvics, J.

    1981-01-01

    Program CYBEAN computes behavior of rolling-element bearings including effects of bearing geometry, shaft misalinement, and temperature. Accurate assessment is possible for various outer-ring and housing configurations. CYBEAN is structured for coordinated execution of modules that perform specific analytical tasks. It is written in FORTRAN IV for use on the UNIVAC 1100/40 computer.

  15. Arcturus and the Bears

    NASA Astrophysics Data System (ADS)

    Antonello, E.

    2009-08-01

    Arcturus is the brightest star in Bootes. The ancient Greek name Arktouros means Bear Guard. The star, however, is not close to Ursa Maior (Big She-Bear) and Ursa Minor (Little She-Bear), as the name would suggest. This curious discrepancy could be explained by the star proper motion, assuming the name Bear Guard is a remote cultural heritage. The proper motion analysis could allow us to get an insight also into an ancient myth regarding Ursa Maior. Though we cannot explain scientifically such a myth, some interesting suggestions can be obtained about its possible origin, in the context of the present knowledge of the importance of the cult of the bear both during the Palaeolithic times and for several primitive populations of modern times, as shown by the ethnological studies.

  16. OTV bearing deflection investigation

    NASA Astrophysics Data System (ADS)

    Reimer, B. L.; Diepenbrock, R. T.; Millis, M. G.

    1993-04-01

    The primary goal of the Bearing Deflectometer Investigation was to gain experience in the use of fiber optic displacement probe technology for bearing health monitoring in a liquid hydrogen turbo pump. The work specified in this Task Order was conducted in conjunction with Air Force Rocket Propulsion Laboratory Contract F04611-86-C-0010. APD conducted the analysis and design coordination to provide a displacement probe design compatible with the XLR-134 liquid hydrogen turbo pump assembly (TPA). Specifications and requirements of the bearing deflectometer were established working with Mechanical Technology Instruments, Inc. (MTI). The TPA design accommodated positioning of the probe to measure outer race cyclic deflections of the pump inlet bearing. The fiber optic sensor was installed as required in the TPA and sensor output was recorded during the TPA testing. Data review indicated that no bearing deflection signature could be differentiated from the inherent system noise. Alternate sensor installations were not investigated, but might yield different results.

  17. 49 CFR 215.107 - Defective plain bearing box: General.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD FREIGHT CAR SAFETY STANDARDS Freight Car Components... service a car, if the car has— (a) A plain bearing box that does not contain visible free oil; (b) A...

  18. 49 CFR 215.107 - Defective plain bearing box: General.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD FREIGHT CAR SAFETY STANDARDS Freight Car Components... service a car, if the car has— (a) A plain bearing box that does not contain visible free oil; (b) A...

  19. 49 CFR 215.107 - Defective plain bearing box: General.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD FREIGHT CAR SAFETY STANDARDS Freight Car Components... service a car, if the car has— (a) A plain bearing box that does not contain visible free oil; (b) A...

  20. 49 CFR 215.107 - Defective plain bearing box: General.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD FREIGHT CAR SAFETY STANDARDS Freight Car Components... service a car, if the car has— (a) A plain bearing box that does not contain visible free oil; (b) A...

  1. 49 CFR 215.107 - Defective plain bearing box: General.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD FREIGHT CAR SAFETY STANDARDS Freight Car Components... service a car, if the car has— (a) A plain bearing box that does not contain visible free oil; (b) A...

  2. Touchdown Ball-Bearing System for Magnetic Bearings

    NASA Technical Reports Server (NTRS)

    Kingsbury, Edward P.; Price, Robert; Gelotte, Erik; Singer, Herbert B.

    2003-01-01

    The torque-limited touchdown bearing system (TLTBS) is a backup mechanical-bearing system for a high-speed rotary machine in which the rotor shaft is supported by magnetic bearings in steady-state normal operation. The TLTBS provides ball-bearing support to augment or supplant the magnetic bearings during startup, shutdown, or failure of the magnetic bearings. The TLTBS also provides support in the presence of conditions (in particular, rotational acceleration) that make it difficult or impossible to control the magnetic bearings or in which the magnetic bearings are not strong enough (e.g., when the side load against the rotor exceeds the available lateral magnetic force).

  3. Magnetically-controlled bearing lubrication

    NASA Technical Reports Server (NTRS)

    Whitaker, A. F.

    1977-01-01

    Proposed magnetic-lubricant ball-bearing assembly has permanently-magnetized bearing retainer fabricated of porous material. Pores of retainer are filled with ferrolubricant. Surface tension causes retainer to deliver sufficient lubricant to nonmagnetic ball bearings.

  4. Evidence for ammonium-bearing minerals in Ceres

    NASA Technical Reports Server (NTRS)

    King, T. V. V.; Clark, R. N.; Calvin, W. M.; Sherman, D. M.; Swayze, G. A.; Brown, R. H.

    1991-01-01

    Evidence for ammonium-bearing minerals was found on the surface of the largest asteroid Ceres. The presence of ammonium-bearing clays suggests that Ceres has experienced a period of alteration by substantial amounts of an ammonium-bearing fluid. The presence of the ammonium-bearing clays does not preclude Ceres maintaining a volatile inventory in the core or in a volatile-rich zone at some distance below the surface. Telescopic observations of Ceres, using the 3.0 meter NASA Infrared telescope facility prompted this reevaluation of its surface mineralogy.

  5. Ball Bearing Mechanics

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.; Dowson, D.

    1981-01-01

    Load-deflection relationships for different types of elliptical contacts such as those found in a ball bearing are developed. Simplified expressions that allow quick calculations of deformation to be made simply from a knowledge of the applied load, the material properties, and the geometry of the contacting elements are presented. Ball bearings subjected to radial, thrust and combined ball loads are analyzed. A design criterion for fatigue life of ball bearings is developed. The section of a satisfactory lubricant, as well as describing systems that provide a constant flow of lubricant to the contact, is considered.

  6. Magnetic bearing update

    SciTech Connect

    Fowler, T.K.

    1995-05-25

    Stabilization of whirl instability by floppy, viscous bearing mounts is discussed and required material properties are estimated for the new tilt-whirl mode in eddy-current stabilized magnetic bearings. A relatively low Young`s modules Y {approximately} 10{sup 5} and high viscosity {zeta} {approximately} 10{sup 7} are required (both in MKS units), suggesting the need for careful mounting design. New information on periodic bearings shows that, thus far, Earshaw`s Theorem cannot be defeated by periodicity, despite the author`s earlier claims.

  7. Ball and Roller Bearings. A Teaching Reference.

    ERIC Educational Resources Information Center

    American Association for Vocational Instructional Materials, Athens, GA.

    The manual provides a subject reference for ball and roller bearings. The following topics are included: (1) bearing nomenclature, (2) bearing uses, (3) bearing capacities, (4) shop area working conditions, (5) bearing removal, (6) bearing cleaning and inspection, (7) bearing replacement, (8) bearing lubrication, (9) bearing installation, (10)…

  8. Arkansas black bear hunter survey

    USGS Publications Warehouse

    Pharris, Larry D.; Clark, Joseph D.

    1987-01-01

    Questionnaires were mailed to black bear (Ursus americanus) hunters in Arkansas following the 1980-84 bear seasons to determine participation, hunter success, and number of bears observed by hunters. Man-days of hunting to harvest a bear ranged from 148 to 671 and hunter success ranged from 0.4% to 2.2%. With the exception of 1980, number of permits issued, man-days of bear hunting, and bears harvested appear affected by hunting permit cost. 

  9. Diclofenac sodium overdose

    MedlinePlus

    Diclofenac sodium is a prescription medicine used to relieve pain and swelling. It is a nonsteroidal anti-inflammatory drug (NSAID). Diclofenac sodium overdose occurs when someone takes more than the ...

  10. Sodium Ferric Gluconate Injection

    MedlinePlus

    Sodium ferric gluconate injection is used to treat iron-deficiency anemia (a lower than normal number of ... are also receiving the medication epoetin (Epogen, Procrit). Sodium ferric gluconate injection is in a class of ...

  11. Docusate Sodium and Pregnancy

    MedlinePlus

    ... live chat Live Help Fact Sheets Share Docusate Sodium Friday, 01 April 2016 In every pregnancy, a ... This sheet talks about whether exposure to docusate sodium may increase the risk for birth defects over ...

  12. Sodium carbonate poisoning

    MedlinePlus

    Sodium carbonate (known as washing soda or soda ash) is a chemical found in many household and ... products. This article focuses on poisoning due to sodium carbonate. This article is for information only. Do ...

  13. Diclofenac sodium overdose

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/002630.htm Diclofenac sodium overdose To use the sharing features on this page, please enable JavaScript. Diclofenac sodium is a prescription medicine used to relieve pain ...

  14. Fractional excretion of sodium

    MedlinePlus

    FE sodium; FENa ... to a lab. There, they are examined for salt (sodium) and creatinine levels. Creatinine is a chemical waste ... your normal foods with a normal amount of salt, unless otherwise instructed by your health care provider. ...

  15. Sodium blood test

    MedlinePlus

    ... able to conserve water) Too much salt or sodium bicarbonate in the diet Use of certain medicines, including corticosteroids, laxatives, lithium, and medicines such as ibuprofen or naproxen Lower than normal sodium level is called hyponatremia. It may be due ...

  16. Roller bearing geometry design

    NASA Technical Reports Server (NTRS)

    Savage, M.; Pinkston, B. H. W.

    1976-01-01

    A theory of kinematic stabilization of rolling cylinders is extended and applied to the design of cylindrical roller bearings. The kinematic stabilization mechanism puts a reverse skew into the rolling elements by changing the roller taper. Twelve basic bearing modification designs are identified amd modeled. Four have single transverse convex curvature in their rollers while eight have rollers which have compound transverse curvature made up of a central cylindrical band surrounded by symmetric bands with slope and transverse curvature. The bearing designs are modeled for restoring torque per unit axial displacement, contact stress capacity, and contact area including dynamic loading, misalignment sensitivity and roller proportion. Design programs are available which size the single transverse curvature roller designs for a series of roller slopes and load separations and which design the compound roller bearings for a series of slopes and transverse radii of curvature. The compound rollers are proportioned to have equal contact stresses and minimum size. Design examples are also given.

  17. Magnetically levitated superconducting bearing

    SciTech Connect

    Weinberger, B.R.; Lynds, L. Jr.

    1993-10-26

    A magnetically levitated superconducting bearing includes a magnet mounted on a shaft that is rotatable around an axis of rotation and a Type II superconductor supported on a stator in proximity to the magnet. The superconductor is positioned so that when it is cooled to its superconducting state in the presence of a magnetic field, it interacts with the magnet to produce an attractive force that levitates the magnet and supports a load on the shaft. The interaction between the superconductor and magnet also produces surface screening currents that generate a repulsive force perpendicular to the load. The bearing also has means for maintaining the superconductor at a temperature below its critical temperature. The bearing could also be constructed so the magnet is supported on the stator and the superconductor is mounted on the shaft. The bearing can be operated by cooling the superconductor to its superconducting state in the presence of a magnetic field. 6 figures.

  18. Hydrostatic bearing support

    NASA Technical Reports Server (NTRS)

    Cunningham, R. E. (Inventor)

    1977-01-01

    A hydrostatic bearing support system is provided which comprises a bearing housing having a polygonally configured outer surface which defines at least three symmetrically disposed working faces and a plurality of pressure plates, each of which is disposed relatively opposite a corresponding working face and spaced therefrom to define a gap therebetween. A hydrostatic support film is created in the gap for supporting the housing in spaced relationship to the pressure plates.

  19. Gear bearing drive

    NASA Technical Reports Server (NTRS)

    Weinberg, Brian (Inventor); Mavroidis, Constantinos (Inventor); Vranish, John M. (Inventor)

    2011-01-01

    A gear bearing drive provides a compact mechanism that operates as an actuator providing torque and as a joint providing support. The drive includes a gear arrangement integrating an external rotor DC motor within a sun gear. Locking surfaces maintain the components of the drive in alignment and provide support for axial loads and moments. The gear bearing drive has a variety of applications, including as a joint in robotic arms and prosthetic limbs.

  20. Deformable bearing seat

    NASA Technical Reports Server (NTRS)

    Moreman, O. S., III (Inventor)

    1977-01-01

    A deformable bearing seat is described for seating a bearing assembly in a housing. The seat includes a seating surface in the housing having a first predetermined spheroidal contour when the housing is in an undeformed mode. The seating surface is deformable to a second predetermined spherically contoured surface when the housing is in a deformed mode. The seat is particularly adaptable for application to a rotating blade and mounting ring assembly in a gas turbine engine.

  1. Load responsive hydrodynamic bearing

    DOEpatents

    Kalsi, Manmohan S.; Somogyi, Dezso; Dietle, Lannie L.

    2002-01-01

    A load responsive hydrodynamic bearing is provided in the form of a thrust bearing or journal bearing for supporting, guiding and lubricating a relatively rotatable member to minimize wear thereof responsive to relative rotation under severe load. In the space between spaced relatively rotatable members and in the presence of a liquid or grease lubricant, one or more continuous ring shaped integral generally circular bearing bodies each define at least one dynamic surface and a plurality of support regions. Each of the support regions defines a static surface which is oriented in generally opposed relation with the dynamic surface for contact with one of the relatively rotatable members. A plurality of flexing regions are defined by the generally circular body of the bearing and are integral with and located between adjacent support regions. Each of the flexing regions has a first beam-like element being connected by an integral flexible hinge with one of the support regions and a second beam-like element having an integral flexible hinge connection with an adjacent support region. A least one local weakening geometry of the flexing region is located intermediate the first and second beam-like elements. In response to application of load from one of the relatively rotatable elements to the bearing, the beam-like elements and the local weakening geometry become flexed, causing the dynamic surface to deform and establish a hydrodynamic geometry for wedging lubricant into the dynamic interface.

  2. Magnetic bearing and motor

    NASA Technical Reports Server (NTRS)

    Studer, P. A. (Inventor)

    1983-01-01

    A magnetic bearing for passively suspending a rotatable element subjected to axial and radial thrust forces is disclosed. The magnetic bearing employs a taut wire stretched along the longitudinal axis of the bearing between opposed end pieces and an intermediate magnetic section. The intermediate section is segmented to provide oppositely directed magnetic flux paths between the end pieces and may include either an axially polarized magnets interposed between the segments. The end pieces, separated from the intermediate section by air gaps, control distribution of magnetic flux between the intermediate section segments. Coaxial alignment of the end pieces with the intermediate section minimizes magnetic reluctance in the flux paths endowing the bearing with self-centering characteristics when subjected to radial loads. In an alternative embodiment, pairs of oppositely wound armature coils are concentrically interposed between segments of the intermediate section in concentric arcs adjacent to radially polarized magnets to equip a magnetic bearing as a torsion drive motor. The magnetic suspension bearing disclosed provides long term reliability without maintenance with application to long term space missions such as the VISSR/VAS scanning mirror instrument in the GOES program.

  3. Investigation of Pressurized Wave Bearings

    NASA Technical Reports Server (NTRS)

    Keith, Theo G., Jr.; Dimofte, Florin

    2003-01-01

    The wave bearing has been pioneered and developed by Dr. Dimofte over the past several years. This bearing will be the main focus of this research. It is believed that the wave bearing offers a number of advantages over the foil bearing, which is the bearing that NASA is currently pursuing for turbomachinery applications. The wave bearing is basically a journal bearing whose film thickness varies around the circumference approximately sinusoidally, with usually 3 or 4 waves. Being a rigid geometry bearing, it provides precise control of shaft centerlines. The wave profile also provides good load capacity and makes the bearing very stable. Manufacturing techniques have been devised that should allow the production of wave bearings almost as cheaply as conventional full-circular bearings.

  4. RUBBER BEARINGS FOR DOWN-HOLE PUMPS

    SciTech Connect

    Bob Sullivan Mammoth Pacific, L.P.

    2005-09-07

    Synopsis of project activity: 1998--Awarded cost share grant from DOE. 1st Qtr 1999--Developed fail safe lubricating system. 2nd Qtr 1999--Performed first large scale test with nitrile based bearings. It failed due to material swelling. Failure was blamed on improper tolerance. 3rd Qtr 1999--Material tests were performed with autoclaves and exposure tests to Casa Diablo fluids. Testing of Viton materials began. Alternate bearing designs were developed to limit risk of improper tolerances. 4th Qtr 1999--Site testing indicated a chemical attack on the bearing material caused the test failure and not improper bearing tolerance. 1st Qtr 2000--The assistance of Brookhaven National Laboratory was obtained in evaluating the chemical attack. The National Laboratory also began more elaborate laboratory testing on bearing materials. 2nd Qtr 2000--Testing indicated Viton was an inappropriate material due to degradation in Casa Diablo fluid. Testing of EPDM began. 3rd Qtr 2001--EPDM bearings were installed for another large scale test. Bearings failed again due to swelling. Further testing indicated that larger then expected oil concentrations existed in lubricating water geothermal fluid causing bearing failure. 2002-2003--Searched for and tested several materials that would survive in hot salt and oil solutions. Kalrez{reg_sign}, Viton{reg_sign}ETP 500 and Viton{reg_sign}GF were identified as possible candidates. 2003-2005--Kalrez{reg_sign}has shown superior resistance to downhole conditions at Casa Diablo from among the various materials tested. Viton ETP-500 indicated a life expectancy of 13 years and because it is significantly less expensive then Kalrez{reg_sign}, it was selected as the bearing material for future testing. Unfortunately during the laboratory testing period Dupont Chemical chose to stop manufacturing this specific formulation and replaced it with Viton ETP 600S. The material is available with six different fillers; three based on zinc oxide and three

  5. Rechargeable sodium alloy anode

    SciTech Connect

    Jow, T.R.

    1988-06-28

    A secondary battery is described comprising: (a) an anode which comprises an alloy of sodium and one or metals selected from the group consisting of tin, lead antimony, bismuth, selenium and tellerium, (b) an electrolyte comprising one or more organic solvents and one or more sodium salts dissolved therein forming dissolved sodium cations in solution; and (c) a cathode; the sodium cations from the electrolyte alloying with the one or more metals of the alloy in the anode during the charging of the battery and sodium in the alloy disoloving in the electrolyte during the discharging of the battery.

  6. Simple modeling of hydrostatic bearings

    NASA Astrophysics Data System (ADS)

    Hull, Charlie

    2014-07-01

    Hydrostatic bearings are a key component for many large telescopes due to their high load bearing capacity, stiffness and low friction. A simple technique is presented to model these bearings to understand the effects of geometry, oil viscosity, flow control, temperature, etc. on the bearings behavior.

  7. Climate Drives Polar Bear Origins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In their provocative analysis of northern bears (“Nuclear genomic sequences reveal that polar bears are an old and distinct bear lineage,” Reports, 20 April, p. 344), F. Hailer et al. use independent nuclear loci to show that polar bears originated during the middle Pleistocene, rather than during t...

  8. Magnetic Bearing Consumes Low Power

    NASA Technical Reports Server (NTRS)

    Studer, P. A.

    1982-01-01

    Energy-efficient linear magnetic bearing maintains a precise small separation between its moving and stationary parts. Originally designed for cryogenic compressors on spacecraft, proposed magnetic bearing offers an alternative to roller or gas bearing in linear motion system. Linear noncontacting bearing operates in environments where lubricants cannot be used.

  9. Factors contributing to the breakdown of sodium beta-alumina

    SciTech Connect

    Buechele, A.C.

    1982-05-01

    Clarification of the breakdown process occurring during charge transfer in sodium beta alumina solid electrolytes was derived from: (1) studying the effects of molten sodium contact at 350/sup 0/C on single crystal sodium beta alumina and polycrystalline sodium beta alumina; (2) determination of critical current density by monitoring acoustic emissions accompanying crack growth in sodium/sodium beta alumina/sodium cells subjected to linear current ramping at 1 mA cm/sup -2/ sec/sup -1/; (3) failure analysis conducted on cycled electrolytes, some from commercial sodium/sulfur cells, which had been subjected to up to 703 Ahr cm/sup -2/ of charge transfer. Gray coloration developing in beta aluminas in contact with molten sodium was found to be a consequence of formation, through reduction by sodium, of oxygen vacancies charge compensated by electrons. Electronic conductivity of the electrolyte increases as a result. No second phase formation was detected. Colored electrolytes from sodium/sulfur cells show evidence of a newly recognized degradation mechanism in which fracture occurs when sodium is reduced and deposited internally under pressure as metal in regions where an electronic conductivity gradient exists. Heating colored beta aluminas in air produces reoxidation and bleaching. Kinetics and other properties of the coloration and bleaching processes were determined. Critical current density was found to bear an inverse relation to average electrolyte grain size. Evidence was found in the cycled electrolytes for a slow crack growth mechanism and a progressive mode of degradation advancing from the sulfur electrode interface. Implications of the findings for the construction and operation of sodium/sulfur battery systems are discussed.

  10. Sodium Recycle Economics for Waste Treatment Plant Operations

    SciTech Connect

    Sevigny, Gary J.; Poloski, Adam P.; Fountain, Matthew S.

    2008-03-01

    Sodium recycle at the Hanford Waste Treatment Plant (WTP) would reduce the number of glass canisters produced, and has the potential to save the U.S. Department of Energy (DOE) tens of millions of dollars. The sodium, added in the form of sodium hydroxide, was originally added to minimize corrosion of carbon-steel storage tanks from acidic reprocessing wastes. In the baseline Hanford treatment process, sodium hydroxide is required to leach gibbsite and boehmite from the high level waste (HLW) sludge. In turn, this reduces the amount of HLW glass produced. Currently, a significant amount of additional sodium hydroxide will be added to the process to maintain aluminate solubility at ambient temperatures during ion exchange of cesium. The vitrification of radioactive waste is limited by sodium content, and this additional sodium mass will increase low-activity waste-glass mass.

  11. Fluid lubricated bearing assembly

    DOEpatents

    Boorse, Henry A.; Boeker, Gilbert F.; Menke, John R.

    1976-01-01

    1. A support for a loaded rotatable shaft comprising in combination on a housing having a fluid-tight cavity encasing an end portion of said shaft, a thrust bearing near the open end of said cavity for supporting the axial thrust of said shaft, said thrust bearing comprising a thrust plate mounted in said housing and a thrust collar mounted on said shaft, said thrust plate having a central opening the peripheral portion of which is hermetically sealed to said housing at the open end of said cavity, and means for supplying a fluid lubricant to said thrust bearing, said thrust bearing having a lubricant-conducting path connecting said lubricant supplying means with the space between said thrust plate and collar intermediate the peripheries thereof, the surfaces of said plate and collar being constructed and arranged to inhibit radial flow of lubricant and, on rotation of said thrust collar, to draw lubricant through said path between the bearing surfaces and to increase the pressure therebetween and in said cavity and thereby exert a supporting force on said end portion of said shaft.

  12. Improved pH buffering agent for sodium hypochlorite

    NASA Technical Reports Server (NTRS)

    Nash, J. R.; Veeder, L. N.

    1969-01-01

    Sodium citrate/citric acid was found to be an effective buffer for pH control when used with sodium hypochlorite. The mixture does not corrode aluminum. The buffer appears to form a type of conversion coating that may provide corrosion-resistant properties to aluminum in other applications.

  13. Solving bearing overheating problems

    SciTech Connect

    Jendzurski, T.

    1995-05-08

    Overheating is a major indicator, along with vibration and noise, of an underlying problem affecting a bearing or related components. Because normal operating temperatures vary widely from one application to another, no single temperature is a reliable sign of overheating in every situation. By observing an application when it is running smoothly, a technician can establish a benchmark temperature for a particular bearing arrangement. Wide deviations from this accepted norm generally indicate troublesome overheating. The list of possible causes of over-heating ranges from out-of-round housings and oversize shaft diameters to excessive lubrication and bearing preloading. These causes fall into two major categories: improper or faulty lubrication and mechanical problems, such as incorrect fits and tolerances. These are discussed along with solutions.

  14. Radial Halbach Magnetic Bearings

    NASA Technical Reports Server (NTRS)

    Eichenberg, Dennis J.; Gallo, Christopher A.; Thompson, William K.

    2009-01-01

    Radial Halbach magnetic bearings have been investigated as part of an effort to develop increasingly reliable noncontact bearings for future high-speed rotary machines that may be used in such applications as aircraft, industrial, and land-vehicle power systems and in some medical and scientific instrumentation systems. Radial Halbach magnetic bearings are based on the same principle as that of axial Halbach magnetic bearings, differing in geometry as the names of these two types of bearings suggest. Both radial and axial Halbach magnetic bearings are passive in the sense that unlike most other magnetic bearings that have been developed in recent years, they effect stable magnetic levitation without need for complex active control. Axial Halbach magnetic bearings were described in Axial Halbach Magnetic Bearings (LEW-18066-1), NASA Tech Briefs, Vol. 32, No. 7 (July 2008), page 85. In the remainder of this article, the description of the principle of operation from the cited prior article is recapitulated and updated to incorporate the present radial geometry. In simplest terms, the basic principle of levitation in an axial or radial Halbach magnetic bearing is that of the repulsive electromagnetic force between (1) a moving permanent magnet and (2) an electric current induced in a stationary electrical conductor by the motion of the magnetic field. An axial or radial Halbach bearing includes multiple permanent magnets arranged in a Halbach array ("Halbach array" is defined below) in a rotor and multiple conductors in the form of wire coils in a stator, all arranged so the rotary motion produces an axial or radial repulsion that is sufficient to levitate the rotor. A basic Halbach array (see Figure 1) consists of a row of permanent magnets, each oriented so that its magnetic field is at a right angle to that of the adjacent magnet, and the right-angle turns are sequenced so as to maximize the magnitude of the magnetic flux density on one side of the row while

  15. Magnetic bearings for spacecraft

    NASA Technical Reports Server (NTRS)

    Studer, P. A.

    1972-01-01

    Magnetic bearings have been successfully applied to motorized rotor systems in the multi-kilogram range, at speeds up to 1200 radians per second. These engineering models also indicated the need for continued development in specific areas to make them feasible for spacecraft applications. Significant power reductions have recently been attained. A unique magnetic circuit, combining permanent magnets with electromagnetic control, has a bidirectional forcing capability with improved current sensitivity. The multi-dimensional nature of contact-free rotor support is discussed. Stable continuous radial suspension is provided by a rotationally symmetric permanent magnet circuit. Two bearings, on a common shaft, counteract the normal instability perpendicular to the rotational axis. The axial direction is servoed to prevent contact. A new bearing technology and a new field of application for magnetics is foreseen.

  16. Partial tooth gear bearings

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (Inventor)

    2010-01-01

    A partial gear bearing including an upper half, comprising peak partial teeth, and a lower, or bottom, half, comprising valley partial teeth. The upper half also has an integrated roller section between each of the peak partial teeth with a radius equal to the gear pitch radius of the radially outwardly extending peak partial teeth. Conversely, the lower half has an integrated roller section between each of the valley half teeth with a radius also equal to the gear pitch radius of the peak partial teeth. The valley partial teeth extend radially inwardly from its roller section. The peak and valley partial teeth are exactly out of phase with each other, as are the roller sections of the upper and lower halves. Essentially, the end roller bearing of the typical gear bearing has been integrated into the normal gear tooth pattern.

  17. Modelling Cometary Sodium Tails

    NASA Astrophysics Data System (ADS)

    Birkett, K. S.; Jones, G. H.; Coates, A. J.

    2013-12-01

    Neutral sodium is readily observed in cometary spectra and can be seen to form its own distinct tail at high activity comets. Solar radiation pressure accelerates the sodium atoms antisunward and, as strong sodium absorption lines are present in the solar spectrum, the magnitude of this force is dependent upon the Doppler shift of the incident solar radiation. Therefore the heliocentric velocity of the sodium atom directly determines its acceleration. This can produce unique effects, such as a stagnation region. Sodium is relatively easy to detect and so can potentially be used to trace mechanisms in the coma that are otherwise difficult to observe. The source of neutral sodium in the tail currently remains unknown. We have therefore developed a new, three dimensional Monte-Carlo model of neutral cometary sodium in order to facilitate testing of different source production functions. It includes weightings due to neutral sodium lifetime, variation of cometary sodium emission due to Fraunhofer absorption lines and solar flux variation with heliocentric distance. The Swings and Greenstein effects, which can have particularly dramatic effects in near-Sun comets, are also considered comprehensively. Preliminary results from this model are presented, focusing on a comparison of predictions of the neutral sodium tail of Comet C/2012 S1 (ISON) with initial observations.

  18. Blood Pump Bearing System

    NASA Technical Reports Server (NTRS)

    Aber, Gregory S. (Inventor)

    2000-01-01

    An apparatus is provided for a blood pump bearing system within a pump housing to support long-term highspeed rotation of a rotor with an impeller blade having a plurality of individual magnets disposed thereon to provide a small radial air gap between the magnets and a stator of less than 0.025 inches. The bearing system may be mounted within a flow straightener, diffuser, or other pump element to support the shaft of a pump rotor. The bearing system includes a zirconia shaft having a radiused end. The radiused end has a first radius selected to be about three times greater than the radius of the zirconia shaft. The radiused end of the zirconia shaft engages a flat sapphire endstone. Due to the relative hardness of these materials a flat is quickly produced during break-in on the zirconia radiused end of precisely the size necessary to support thrust loads whereupon wear substantially ceases. Due to the selection of the first radius, the change in shaft end-play during pump break-in is limited to a total desired end-play of less than about 0.010 inches. Radial loads are supported by an olive hole ring jewel that makes near line contact around the circumference of the Ir shaft to support big speed rotation with little friction. The width of olive hole ring jewel is small to allow heat to conduct through to thereby prevent heat build-up in the bearing. A void defined by the bearing elements may fill with blood that then coagulates within the void. The coagulated blood is then conformed to the shape of the bearing surfaces.

  19. Blood Pump Bearing System

    NASA Technical Reports Server (NTRS)

    Aber, Gregory S. (Inventor)

    1999-01-01

    Methods and apparatus are provided for a blood pump bearing system within a pump housing to support long-term high-speed rotation of a rotor with an impeller blade having a plurality of individual magnets disposed thereon to provide a small radial air gap between the magnets and a stator of less than 0.025 inches. The bearing system may be mounted within a flow straightener, diffuser, or other pump element to support the shaft of a pump rotor. The bearing system includes a zirconia shaft having a radiused end. The radiused end has a first radius selected to be about three times greater than the radius of the zirconia shaft. The radiused end of the zirconia shaft engages a flat sapphire endstone. Due to the relative hardness of these materials a flat is quickly produced during break-in on the zirconia radiused end of precisely the size necessary to support thrust loads whereupon wear substantially ceases. Due to the selection of the first radius, the change in shaft end-play during pump break-in is limited to a total desired end-play of less than about 0.010 inches. Radial loads are supported by an olive hole ring jewel that makes near line contact around the circumference of the shaft to support high speed rotation with little friction. The width of olive hole ring jewel is small to allow heat to conduct through to thereby prevent heat build-up in the bearing. A void defined by the bearing elements may fill with blood that then coagulates within the void. The coagulated blood is then conformed to the shape of the bearing surfaces.

  20. Modular gear bearings

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (Inventor)

    2009-01-01

    A gearing system using modular gear bearing components. Each component is composed of a core, one or more modules attached to the core and two or more fastening modules rigidly attaching the modules to the core. The modules, which are attached to the core, may consist of gears, rollers or gear bearing components. The core orientation affects the orientation of the modules attached to the core. This is achieved via the keying arrangement of the core and the component modules that attach to the core. Such an arrangement will also facilitate the phase tuning of gear modules with respect to the core and other gear modules attached to the core.

  1. Sodium remote from Io

    NASA Astrophysics Data System (ADS)

    Brown, R. A.; Schneider, N. M.

    1981-12-01

    Measurements of sodium emission lines originating in the middle Jupiter magnetosphere are measured, confirming the wide dispersal of neutral sodium in the Jovian system in at least two distinct manifestations. Candidate neutral transport processes in the context of the observed kinematical signatures are discussed. It is argued that the normal emission feature is produced by sodium atoms on bound elliptical orbits originating in the Io sodium cloud but with apojove in the field of view. Observations of the fast sodium feature indicate that atoms episodically acquire a broad range of line-of-sight velocities above the Jupiter gravitational escape speed and far above the speeds characteristic of surface-sputtered atoms. Three suggested reactions are distinguished according to (1) production rates based on estimated plasmaspheric properties, (2) kinematical signature, and (3) the timing of occurrences of the fast sodium feature.

  2. History of ball bearings

    NASA Technical Reports Server (NTRS)

    Dowson, D.; Hamrock, B. J.

    1981-01-01

    The familiar precision rolling-element bearings of the twentieth century are products of exacting technology and sophisticated science. Their very effectiveness and basic simplicity of form may discourage further interest in their history and development. Yet the full story covers a large portion of recorded history and surprising evidence of an early recognition of the advantages of rolling motion over sliding action and progress toward the development of rolling-element bearings. The development of rolling-element bearings is followed from the earliest civilizations to the end of the eighteenth century. The influence of general technological developments, particularly those concerned with the movement of large building blocks, road transportation, instruments, water-raising equipment, and windmills are discussed, together with the emergence of studies of the nature of rolling friction and the impact of economic factors. By 1800 the essential features of ball and rolling-element bearings had emerged and it only remained for precision manufacture and mass production to confirm the value of these fascinating machine elements.

  3. Hybrid superconductor magnet bearings

    SciTech Connect

    Chu, W.

    1995-04-01

    Hybrid superconductor magnet bearings (HSMB`s) utilize high temperature superconductors (HTS`s) together with permanent magnets to form a frictionless interface between relatively rotating parts. They are low mass, stable, and do not incur expenditure of energy during normal operation. There is no direct physical contact between rotor and stator, and hence there is no wear and tear. However, just as any other applications of HTS`s, it requires a very cold temperature to function. Whereas this might be perceived as a disadvantage on earth, it is of no great concern in space or on the moon. To astronomers, the moon is an excellent site for an observatory, but the cold and dusty vacuum environment on the moon precludes the use of mechanical bearings on the telescope mounts. Furthermore, drive mechanisms with very fine steps, and hence bearings with extremely low friction are needed to track a star from the moon, because the moon rotates very slowly. All aspects considered, the HSMB is about the only candidate that fits in naturally. Here, the authors present a design for one such bearing, capable of supporting a telescope that weighs about 3 lbs on Earth.

  4. Hybrid superconductor magnet bearings

    NASA Astrophysics Data System (ADS)

    Chu, Wei-Kan

    1995-04-01

    Hybrid superconductor magnet bearings (HSMB's) utilize high temperature superconductors (HTS's) together with permanent magnets to form a frictionless interface between relatively rotating parts. They are low mass, stable, and do not incur expenditure of energy during normal operation. There is no direct physical contact between rotor and stator, and hence there is no wear and tear. However, just as any other applications of HTS's, it requires a very cold temperature to function. Whereas this might be perceived as a disadvantage on earth, it is of no great concern in space or on the moon. To astronomers, the moon is an excellent site for an observatory, but the cold and dusty vacuum environment on the moon precludes the use of mechanical bearings on the telescope mounts. Furthermore, drive mechanisms with very fine steps, and hence bearings with extremely low friction are needed to track a star from the moon, because the moon rotates very slowly. All aspects considered, the HSMB is about the only candidate that fits in naturally. Here, we present a design for one such bearing, capable of supporting a telescope that weighs about 3 lbs on Earth.

  5. Magnetic Bearings For Turbopumps

    NASA Technical Reports Server (NTRS)

    Meeks, Crawford R.; Mendez, Antonio J.

    1995-01-01

    Report presents study of feasibility of magnetic bearings in turbopumps. Liquid-oxygen turbopump in space shuttle main engine selected for study. Other potential applications include manned and unmanned spacecraft, gas turbines for commercial and military aircraft, turbomachinery for petro-chemical and gas operations, suspension systems for precise machinery, and precise pointing and tracking systems.

  6. The Teddy Bears' Disc.

    ERIC Educational Resources Information Center

    Laurillard, Diana

    1985-01-01

    Reports an evaluation of the Teddy Bear disc, an interactive videodisc developed at the Open University for a second-level course in metallurgy and materials technology. Findings from observation of students utilizing the videodisc are reviewed; successful design features and design problems are considered; and development costs are outlined. (MBR)

  7. Hybrid superconductor magnet bearings

    NASA Technical Reports Server (NTRS)

    Chu, Wei-Kan

    1995-01-01

    Hybrid superconductor magnet bearings (HSMB's) utilize high temperature superconductors (HTS's) together with permanent magnets to form a frictionless interface between relatively rotating parts. They are low mass, stable, and do not incur expenditure of energy during normal operation. There is no direct physical contact between rotor and stator, and hence there is no wear and tear. However, just as any other applications of HTS's, it requires a very cold temperature to function. Whereas this might be perceived as a disadvantage on earth, it is of no great concern in space or on the moon. To astronomers, the moon is an excellent site for an observatory, but the cold and dusty vacuum environment on the moon precludes the use of mechanical bearings on the telescope mounts. Furthermore, drive mechanisms with very fine steps, and hence bearings with extremely low friction are needed to track a star from the moon, because the moon rotates very slowly. All aspects considered, the HSMB is about the only candidate that fits in naturally. Here, we present a design for one such bearing, capable of supporting a telescope that weighs about 3 lbs on Earth.

  8. Composite Bear Canister

    NASA Technical Reports Server (NTRS)

    Chung, W. Richard; Jara, Steve; Suffel, Susan

    2003-01-01

    To many national park campers and mountain climbers saving their foods in a safe and unbreakable storage container without worrying being attacked by a bear is a challenging task. In some parks, the park rangers have mandated that park visitors rent a bear canister for their food storage. Commercially available bear canisters are made of ABS plastic, weigh 2.8 pounds, and have a 180 cubic inch capacity for food storage. A new design with similar capacity was conducted in this study to reduce its weight and make it a stiffer and stronger canister. Two prototypes incorporating carbon prepreg with and without honeycomb constructions were manufactured using hand lay-up and vacuum bag forming techniques. A 6061-T6-aluminum ring was machined to dimensions in order to reinforce the opening area of the canister. Physical properties (weight and volume) along with mechanical properties (flexural strength and specific allowable moment) of the newly fabricated canisters are compared against the commercial ones. The composite canister weighs only 56% of the ABS one can withstand 9 times of the force greater. The advantages and limitations of using composite bear canisters will be discussed in the presentation.

  9. Optimal Synchronizability of Bearings

    NASA Astrophysics Data System (ADS)

    Araújo, N. A. M.; Seybold, H.; Baram, R. M.; Herrmann, H. J.; Andrade, J. S., Jr.

    2013-02-01

    Bearings are mechanical dissipative systems that, when perturbed, relax toward a synchronized (bearing) state. Here we find that bearings can be perceived as physical realizations of complex networks of oscillators with asymmetrically weighted couplings. Accordingly, these networks can exhibit optimal synchronization properties through fine-tuning of the local interaction strength as a function of node degree [Motter, Zhou, and Kurths, Phys. Rev. E 71, 016116 (2005)PLEEE81539-3755]. We show that, in analogy, the synchronizability of bearings can be maximized by counterbalancing the number of contacts and the inertia of their constituting rotor disks through the mass-radius relation, m˜rα, with an optimal exponent α=α× which converges to unity for a large number of rotors. Under this condition, and regardless of the presence of a long-tailed distribution of disk radii composing the mechanical system, the average participation per disk is maximized and the energy dissipation rate is homogeneously distributed among elementary rotors.

  10. Magnetically leviated superconducting bearing

    DOEpatents

    Weinberger, Bernard R.; Lynds, Jr., Lahmer

    1993-01-01

    A magnetically levitated superconducting bearing includes a magnet (2) mounted on a shaft (12) that is rotatable around an axis of rotation and a Type II superconductor (6) supported on a stator (14) in proximity to the magnet (2). The superconductor (6) is positioned so that when it is cooled to its superconducting state in the presence of a magnetic field, it interacts with the magnet (2) to produce an attractive force that levitates the magnet (2) and supports a load on the shaft (12). The interaction between the superconductor (6) and magnet(2) also produces surface screening currents (8) that generate a repulsive force perpendicular to the load. The bearing also has means for maintaining the superconductor at a temperature below its critical temperature (16, 18). The bearing could also be constructed so the magnet (2) is supported on the stator (14) and the superconductor (6) is mounted on the shaft (12). The bearing can be operated by cooling the superconductor (6) to its superconducting state in the presence of a magnetic field.

  11. Sodium Polystyrene Sulfonate

    MedlinePlus

    ... allergic to sodium polystyrene sulfonate, other polystyrene sulfonate resins, any other medications, or any of the ingredients ... salt substitutes containing potassium or foods that are high in potassium.

  12. Lubricant effects on bearing life

    NASA Technical Reports Server (NTRS)

    Zaretsky, Erwin V.

    1986-01-01

    Lubricant considerations for rolling-element bearings have within the last two decades taken on added importance in the design and operation of mechanical systems. The phenomenon which limits the useful life of bearings is rolling-element or surface pitting fatigue. The elastohydrodynamic (EHD) film thickness which separates the ball or roller surface from those of the raceways of the bearing directly affects bearing life. Chemical additives added to the lubricant can also significantly affect bearings life and reliability. The interaction of these physical and chemical effects is important to the design engineer and user of these systems. Design methods and lubricant selection for rolling-element bearings are presented and discussed.

  13. Magnetic-Bearing Test Fixture

    NASA Technical Reports Server (NTRS)

    Groom, Nelson J.; Poole, William L.

    1991-01-01

    Microcomputer-controlled magnetic-bearing test fixture used to develop approaches to design of controls for magnetic bearing actuators designed and constructed. Includes load cells connected to bar, in turn, connected through screw positioners to geared drive motors. Position of equivalent suspended element sensed by position sensors and controlled by drive motors. Provides control of gap in magnetic bearing and of current in electromagnet coil. Measurements made include magnetic-bearing gaps, magnetic flux in bearing gaps, and bearing forces. Approaches to linearization and control developed by use of fixture applicable to wide range of small-gap suspension systems.

  14. Flexure Bearing Reduces Startup Friction

    NASA Technical Reports Server (NTRS)

    Clingman, W. Dean

    1991-01-01

    Design concept for ball bearing incorporates small pieces of shim stock, wire spokes like those in bicycle wheels, or other flexing elements to reduce both stiction and friction slope. In flexure bearing, flexing elements placed between outer race of ball bearing and outer ring. Elements flex when ball bearings encounter small frictional-torque "bumps" or even larger ones when bearing balls encounter buildups of grease on inner or outer race. Flexure of elements reduce high friction slopes of "bumps", helping to keep torque between outer ring and inner race low and more nearly constant. Concept intended for bearings in gimbals on laser and/or antenna mirrors.

  15. Tribology of hard bearing coatings

    SciTech Connect

    Santavy, A.P.; Scattergood, R.O.

    1996-12-31

    The performance of a linear sliding contact bearing is dictated by a frictional effect called stiction. Stiction exists when the static coefficient of friction is substantially higher than the dynamic coefficient. Stiction can cause chatter or jerky motion when attempting to move a slide at low speed. The force required to overcome static friction will cause deflection in the structure of the machine. If the dynamic coefficient is less than the static coefficient, when the slide breaks loose the friction force is suddenly reduced and there is an excess force on the slide and it is accelerated by this unbalanced force. As the slide moves relative to the rest of the structure the force due to the deflection of the structure is relieved. The inertia of the slide will carry it beyond the equilibrium point until the force on the slide is less than that required to overcome dynamic friction and the slide will stop. This process repeats. At high speeds, chatter does not occur because the velocity due to the suddenly unbalanced force at breakaway is small compared to the overall velocity so that the slide never comes to rest. For friction materials with a dynamic coefficient that is not less than static, stiction induced chatter does not occur because there is no excess force when the slide breaks away.

  16. Caustic Recycling Pilot Unit to Separate Sodium from LLW at Hanford Site - 12279

    SciTech Connect

    Pendleton, Justin; Bhavaraju, Sai; Priday, George; Desai, Aditya; Duffey, Kean; Balagopal, Shekar

    2012-07-01

    As part of the Department of Energy (DOE) sponsored Advanced Remediation Technologies initiative, a scheme was developed to combine Continuous Sludge Leaching (CSL), Near-Tank Cesium Removal (NTCR), and Caustic Recycling Unit (CRU) using Ceramatec technology, into a single system known as the Pilot Near-Tank Treatment System (PNTTS). The Cesium (Cs) decontaminated effluent from the NTCR process will be sent to the caustic recycle process for recovery of the caustic which will be reused in another cycle of caustic leaching in the CSL process. Such an integrated mobile technology demonstration will give DOE the option to insert this process for sodium management at various sites in Hanford, and will minimize the addition of further sodium into the waste tanks. This allows for recycling of the caustic used to remove aluminum during sludge washing as a pretreatment step in the vitrification of radioactive waste which will decrease the Low Level Waste (LLW) volume by as much as 39%. The CRU pilot process was designed to recycle sodium in the form of pure sodium hydroxide. The basis for the design of the 1/4 scale pilot caustic recycling unit was to demonstrate the efficient operation of a larger scale system to recycle caustic from the NTCR effluent stream from the Parsons process. The CRU was designed to process 0.28 liter/minute of NTCR effluent, and generate 10 M concentration of 'usable' sodium hydroxide. The proposed process operates at 40 deg. C to provide additional aluminum solubility and then recover the sodium hydroxide to the point where the aluminum is saturated at 40 deg. C. A system was developed to safely separate and vent the gases generated during operation of the CRU with the production of 10 M sodium hydroxide. Caustic was produced at a rate between 1.9 to 9.3 kg/hr. The CRU was located inside an ISO container to allow for moving of the unit close to tank locations to process the LLW stream. Actual tests were conducted with the NTCR effluent simulant

  17. Particle migration through sealed bearings

    SciTech Connect

    Sundvold, P.D.

    1993-08-01

    Tests were performed to determine the ability of various types of shielded bearings to isolate particulate from a clean environment in support of the Direct Optical Initiation (DOI) program. In the DOI firing system, a stronglink mechanism will share the same environment with a high-powered laser which needs uncontaminated optics to perform properly. Two commercially available shielded and sealed bearings were tested along with a sealed bearing designed at Allied Signal Inc., Kansas City Division (KCD). The KCD-designed bearing proved to be the best barrier, but the torque required to function the bearing was magnitudes above the commercial bearings. The commercial sealed bearing was an effective barrier, allowing a small fraction of particles to migrate through, and had a relatively low running torque. The shielded bearing was not acceptable as a particle barrier.

  18. Vygotsky and the Three Bears

    ERIC Educational Resources Information Center

    Kulczewski, Peggy

    2004-01-01

    Peggy Kulczewski, a kindergarten classroom teacher, remembers the day when students enjoyed a story she told them from the book "The Three Bears". The students' discussion about comparison of the bears was very helpful to the whole group.

  19. Magnetic bearings grow more attractive

    SciTech Connect

    Not Available

    1993-10-01

    Advances in materials and electronics have enabled designers to devise simpler, smaller magnetic bearings. As a result, costs have dropped, widening the applications for these very-low-friction devices. Avcon (Advanced Controls Technology) has patented a permanent-magnet bias actively controlled bearing. Here high-energy rare earth permanent-magnet materials supply the basic bearing load levitation, while servo-driven electromagnets generate stabilization and centering forces for motion contol. Previous heavy-duty magnetic bearings used electromagnets entirely for suspension and control, which led to large bearings and control systems with higher power requirements. Avcon has developed several types of permanent-magnet bias bearings. The simplest is the radial repulsion bearing. Avcon's homopolar permanent-magnet bias active bearing is the most versatile of the company's designs.

  20. Thermophysical properties of sodium

    NASA Technical Reports Server (NTRS)

    Golden, G. H.; Tokar, J. V.

    1969-01-01

    Assessment is given of physical and thermodynamic properties of sodium. FORTRAN subroutine computes enthalphy and entropy of sodium in given state, and composition, molecular weight, volume, and compressibility factor of corresponding vapor. Tabular results for saturated liquid and vapor are presented for a 500-2500 degree F range.

  1. Externally Pressurized Journal Gas Bearings

    NASA Technical Reports Server (NTRS)

    Laub, John H.

    1959-01-01

    Externally pressurized gas-lubricated bearings with multiple orifice feed are investigated. An analytical treatment is developed for a semi-cylindrical bearing with 9 orifices and for a cylindrical journal bearing with 192 radial and 24 axial orifices. Experiments are described on models of the two bearing configurations with specially designed fixtures which incorporate pneumatic loading and means for determining pressure profiles, gas flow and gap height. The correlation between theory and experiment is satisfactory.

  2. Passive magnetic bearing system

    DOEpatents

    Post, Richard F.

    2014-09-02

    An axial stabilizer for the rotor of a magnetic bearing provides external control of stiffness through switching in external inductances. External control also allows the stabilizer to become a part of a passive/active magnetic bearing system that requires no external source of power and no position sensor. Stabilizers for displacements transverse to the axis of rotation are provided that require only a single cylindrical Halbach array in its operation, and thus are especially suited for use in high rotation speed applications, such as flywheel energy storage systems. The elimination of the need of an inner cylindrical array solves the difficult mechanical problem of supplying support against centrifugal forces for the magnets of that array. Compensation is provided for the temperature variation of the strength of the magnetic fields of the permanent magnets in the levitating magnet arrays.

  3. Magnetic bearing and motor

    NASA Technical Reports Server (NTRS)

    Studer, Philip A. (Inventor)

    1983-01-01

    A magnetic bearing assembly (10) has an intermediate rotatable section (33) having an outer cylindrical member (30) coaxially suspended by a torsion wire (72) around an axially polarized cylindrical magnet (32). Axial alignment between the pole faces (40-43) of the intermediate section (33) and end surfaces (50-53) of opposed end bells (20, 22) provides a path of least reluctance across intervening air gaps (60-63) for the magnetic flux emanating from magnet (32). Radial dislocation increases the reluctance and creates a radial restoring force. Substitution of radially polarized magnets 107 fixed to a magnetically permeable cylinder (32') and insertion of pairs of armature coil windings (109-112) between the cylinder pair (33') provides an integral magnetic bearing and torsion motor (100) able to provide arcuately limited rotational drive.

  4. Centrifugally decoupling touchdown bearings

    DOEpatents

    Post, Richard F

    2014-06-24

    Centrifugally decoupling mechanical bearing systems provide thin tensioned metallic ribbons contained in a support structure. This assembly rotates around a stationary shaft being centered at low speeds by the action of the metal ribbons. Tension springs are connected on one end to the ribbons and on the other end to the support structure. The ribbons pass through slots in the inner ring of the support structure. The spring preloading thus insures contact (or near-contact) between the ribbons and the shaft at rotation speeds below the transition speed. Above this speed, however, the centrifugal force on the ribbons produces a tensile force on them that exceeds the spring tensile force so that the ribbons curve outward, effectively decoupling them from mechanical contact with the shaft. They still remain, however, in position to act as a touchdown bearing in case of abnormally high transverse accelerations.

  5. Rotating plug bearing and seal

    DOEpatents

    Wade, Elman E.

    1977-01-01

    A bearing and seal structure for nuclear reactors utilizing rotating plugs above the nuclear reactor vessel. The structure permits lubrication of bearings and seals of the rotating plugs without risk of the lubricant draining into the reactor vessel below. The structure permits lubrication by utilizing a rotating outer race bearing.

  6. Frictionless Bearing Uses Permanent Magnets

    NASA Technical Reports Server (NTRS)

    1965-01-01

    The purpose of this innovation was to develop a frictionless bearing for high speed, light load applications. The device involves the incorporation of permanent magnets in the bearing design. The repulsion of like magnetic poles provides concentric support of the inner member so that no metallic contact occurs between the bearing surfaces.

  7. Big Bear Solar Observatory

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Big Bear Solar Observatory (BBSO) is located at the end of a causeway in a mountain lake more than 2 km above sea level. The site has more than 300 sunny days a year and a natural inversion caused by the lake which makes for very clean images. BBSO is the only university observatory in the US making high-resolution observations of the Sun. Its daily images are posted at http://www.bbso.njit.e...

  8. Radium bearing waste disposal

    SciTech Connect

    Tope, W.G.; Nixon, D.A.; Smith, M.L.; Stone, T.J.; Vogel, R.A.; Schofield, W.D.

    1995-07-01

    Fernald radium bearing ore residue waste, stored within Silos 1 and 2 (K-65) and Silo 3, will be vitrified for disposal at the Nevada Test Site (NTS). A comprehensive, parametric evaluation of waste form, packaging, and transportation alternatives was completed to identify the most cost-effective approach. The impacts of waste loading, waste form, regulatory requirements, NTS waste acceptance criteria, as-low-as-reasonably-achievable principles, and material handling costs were factored into the recommended approach.

  9. Magnetic translator bearings

    NASA Technical Reports Server (NTRS)

    Hockney, Richard L. (Inventor); Downer, James R. (Inventor); Eisenhaure, David B. (Inventor); Hawkey, Timothy J. (Inventor); Johnson, Bruce G. (Inventor)

    1990-01-01

    A magnetic bearing system for enabling translational motion includes a carriage and a shaft for movably supporting the carriage; a first magnetic bearing fixed to one of the carriage and shaft and slidably received in a first channel of the other of the carriage and shaft. The first channel is generally U shaped with two side walls and a back wall. The magnetic bearing includes a pair of spaced magnetic pole pieces, each pole piece having a pair of electromagnetic coils mounted on poles on opposite ends of the pole piece proximate the side walls, and a third electromagnetic coil mounted on a pole of the pole piece proximate the backwall; a motion sensor for sensing translational motion along two axes and rotationally about three axes of the carriage and shaft relative to each other; and a correction circuit responsive to the sensor for generating a correction signal to drive the coils to compensate for any misalignment sensed between the carriage and the shaft.

  10. The series hybrid bearing - A new high speed bearing concept.

    NASA Technical Reports Server (NTRS)

    Anderson, W. J.; Fleming, D. P.; Parker, R. J.

    1971-01-01

    The series-hybrid bearing couples a fluid-film bearing with a rolling-element bearing such that the rolling-element bearing inner race runs at a fraction of shaft speed. A series-hybrid bearing was analyzed and experiments were run at thrust loads from 100 to 300 lb and speeds from 4000 to 30,000 rpm. Agreement between theoretical and experimental speed sharing was good. The lowest speed ratio (ratio of ball bearing inner-race speed to shaft speed) obtained was 0.67. This corresponds to an approximate reduction in DN value of 1/3. For a ball bearing in a 3 million DN application, fatigue life would theoretically be improved by a factor as great as 8.

  11. Decode the Sodium Label Lingo

    MedlinePlus

    ... For Preschooler For Gradeschooler For Teen Decode the Sodium Label Lingo Published January 24, 2013 Print Email Reading food labels can help you slash sodium. Here's how to decipher them. "Sodium free" or " ...

  12. Design of a compliant passive magnetic bearing for use in SIRTF's Tertiary Mirror Assembly

    NASA Technical Reports Server (NTRS)

    Cannon, David M.; Brereton, Margot; Dill, Harry; Sullivan, Mark

    1990-01-01

    A proposed baseline design for the Space Infrared Telescope Facility includes a Tertiary Mirror Assembly (TMA) which selectively redirects the telescope's converging science beam to each of several instruments. The TMA's mirror rotates on an axis coincident with the beam's axis, and is held steady during observation by a kinematic mount. A bearing has been designed whose compliance causes minimal interference with the precision of the kinematic mount, and which is well suited to the particular requirements of a cryogenic satellite such as SIRTF. The bearing suspends its rotor by taking advantage of the repulsion between a superconductor and a magnet. It potentially eliminates problems associated with mechanical bearings that arise in similar applications, such as lubricant loss or failure, bearing wear, and sensitivity to particulates, and does so without imposing the thermal load of a bearing heater or active magnetic bearing. The bearing shows promise of offering an alternative to ball bearings in cryogenic applications where some compliance is acceptable or advantageous.

  13. Lactic acid conversion to 2,3-pentanedione and acrylic acid over silica-supported sodium nitrate: Reaction optimization and identification of sodium lactate as the active catalyst

    SciTech Connect

    Wadley, D.C.; Tam, M.S.; Miller, D.J.

    1997-01-15

    Lactic acid is converted to 2,3-pentanedione, acrylic acid, and other products in vapor-phase reactions over silica-supported sodium lactate formed from sodium nitrate. Multiparameter optimization of reaction conditions using a Box-Benkhen experimental design shows that the highest yield and selectivity to 2,3-pentanedione are achieved at low temperature, elevated pressure, and long contact time, while yield and selectivity to acrylic acid are most favorable at high temperature, low pressure, and short contact time. Post-reaction Fourier transform infrared spectroscopic analyses of the catalyst indicate that sodium nitrate as the initial catalyst material is transformed to sodium lactate at the onset of reaction via proton transfer from lactic acid to nitrate. The resultant nitric acid vaporizes as it is formed, leaving sodium lactate as the sole sodium-bearing species on the catalyst during reaction. 19 refs., 8 figs., 5 tabs.

  14. METHOD FOR REMOVING SODIUM OXIDE FROM LIQUID SODIUM

    DOEpatents

    Bruggeman, W.H.; Voorhees, B.G.

    1957-12-01

    A method is described for removing sodium oxide from a fluent stream of liquid sodium by coldtrapping the sodium oxide. Apparatus utilizing this method is disclosed in United States Patent No. 2,745,552. Sodium will remain in a molten state at temperatures below that at which sodium oxide will crystallize out and form solid deposits, therefore, the contaminated stream of sodium is cooled to a temperature at which the solubility of sodium oxide in sodium is substantially decreased. Thereafter the stream of sodium is passed through a bed of stainless steel wool maintained at a temperature below that of the stream. The stream is kept in contact with the wool until the sodium oxide is removed by crystal growth on the wool, then the stream is reheated and returned to the system. This method is useful in purifying reactor coolants where the sodium oxide would otherwise deposit out on the walls and eventually plug the coolant tubes.

  15. Anti-backlash gear bearings

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (Inventor)

    2009-01-01

    A gear bearing having a first gear and a second gear, each having a plurality of teeth. Each gear operates on two non-parallel surfaces of the opposing gear teeth to perform both gear and bearing functions simultaneously. The gears are moving at substantially the same speed at their contact points. The gears may be roller gear bearings or phase-shifted gear bearings, and may be arranged in a planet/sun system or used as a transmission. One preferred embodiment discloses and describes an anti-backlash feature to counter ''dead zones'' in the gear bearing movement.

  16. Hybrid Bearing Prognostic Test Rig

    NASA Technical Reports Server (NTRS)

    Dempsey, Paula J.; Certo, Joseph M.; Handschuh, Robert F.; Dimofte, Florin

    2005-01-01

    The NASA Glenn Research Center has developed a new Hybrid Bearing Prognostic Test Rig to evaluate the performance of sensors and algorithms in predicting failures of rolling element bearings for aeronautics and space applications. The failure progression of both conventional and hybrid (ceramic rolling elements, metal races) bearings can be tested from fault initiation to total failure. The effects of different lubricants on bearing life can also be evaluated. Test conditions monitored and recorded during the test include load, oil temperature, vibration, and oil debris. New diagnostic research instrumentation will also be evaluated for hybrid bearing damage detection. This paper summarizes the capabilities of this new test rig.

  17. Bearing for liquid metal pump

    DOEpatents

    Dickinson, Robert J.; Wasko, John; Pennell, William E.

    1984-01-01

    A liquid metal pump bearing support comprises a series of tangentially oriented spokes that connect the bearing cylinder to the pump internals structure. The spokes may be arranged in a plurality of planes extending from the bearing cylinder to the pump internals with the spokes in one plane being arranged alternately with those in the next plane. The bearing support structure provides the pump with sufficient lateral support for the bearing structure together with the capability of accommodating differential thermal expansion without adversely affecting pump performance.

  18. Bearing, gearing, and lubrication technology

    NASA Technical Reports Server (NTRS)

    Anderson, W. J.

    1978-01-01

    Results of selected NASA research programs on rolling-element and fluid-film bearings, gears, and elastohydrodynamic lubrication are reported. Advances in rolling-element bearing material technology, which have resulted in a significant improvement in fatigue life, and which make possible new applications for rolling bearings, are discussed. Research on whirl-resistant, fluid-film bearings, suitable for very high-speed applications, is discussed. An improved method for predicting gear pitting life is reported. An improved formula for calculating the thickness of elastohydrodynamic films (the existence of which help to define the operating regime of concentrated contact mechanisms such as bearings, gears, and cams) is described.

  19. Bearing construction for refrigeration compressor

    SciTech Connect

    Middleton, M.G.; Nelson, R.T.

    1988-01-12

    A hermetic refrigeration compressor has a cylinder block and a crankshaft rotatable about a vertical axis to reciprocate a piston in a cylinder on the cylinder block. A separate bearing housing is secured to the central portion of the cylinder block and extends vertically along the crankshaft, where it carries a pair of roller bearings to journal the crankshaft. The crankshaft has a radially extending flange which is journaled by a thrust-type roller bearing above the bearing housing to absorb the vertical forces on the crankshaft so that all three of the roller bearings are between the crankshaft and the bearing housing to maintain and control the close tolerances required by such bearings. 4 figs.

  20. Bearing construction for refrigeration compresssor

    DOEpatents

    Middleton, Marc G.; Nelson, Richard T.

    1988-01-01

    A hermetic refrigeration compressor has a cylinder block and a crankshaft rotatable about a vertical axis to reciprocate a piston in a cylinder on the cylinder block. A separate bearing housing is secured to the central portion of the cylinder block and extends vertically along the crankshaft, where it carries a pair of roller bearings to journal the crankshaft. The crankshaft has a radially extending flange which is journaled by a thrust-type roller bearing above the bearing housing to absorb the vertical forces on the crankshaft so that all three of the roller bearings are between the crankshaft and the bearing housing to maintain and control the close tolerances required by such bearings.

  1. Damping Bearings In High-Speed Turbomachines

    NASA Technical Reports Server (NTRS)

    Von Pragenau, George L.

    1994-01-01

    Paper presents comparison of damping bearings with traditional ball, roller, and hydrostatic bearings in high-speed cryogenic turbopumps. Concept of damping bearings described in "Damping Seals and Bearings for a Turbomachine" (MFS-28345).

  2. Submersible sodium pump

    DOEpatents

    Brynsvold, Glen V.; Lopez, John T.; Olich, Eugene E.; West, Calvin W.

    1989-01-01

    An electromagnetic submerged pump has an outer cylindrical stator with an inner cylindrical conductive core for the submerged pumping of sodium in the cylindrical interstitial volume defined between the stator and core. The cylindrical interstitial volume is typically vertically oriented, and defines an inlet at the bottom and an outlet at the top. The outer stator generates upwardly conveyed toroidal magnetic fields, which fields convey preferably from the bottom of the pump to the top of the pump liquid sodium in the cold leg of a sodium cooled nuclear reactor. The outer cylindrical stator has a vertically disposed duct surrounded by alternately stacked layers of coil units and laminates.

  3. SODIUM DEUTERIUM REACTOR

    DOEpatents

    Oppenheimer, E.D.; Weisberg, R.A.

    1963-02-26

    This patent relates to a barrier system for a sodium heavy water reactor capable of insuring absolute separation of the metal and water. Relatively cold D/sub 2/O moderator and reflector is contained in a calandria into which is immersed the fuel containing tubes. The fuel elements are cooled by the sodium which flows within the tubes and surrounds the fuel elements. The fuel containing tubes are surrounded by concentric barrier tubes forming annular spaces through which pass inert gases at substantially atmospheric pressure. Header rooms above and below the calandria are provided for supplying and withdrawing the sodium and inert gases in the calandria region. (AEC)

  4. Submersible sodium pump

    DOEpatents

    Brynsvold, G.V.; Lopez, J.T.; Olich, E.E.; West, C.W.

    1989-11-21

    An electromagnetic submerged pump has an outer cylindrical stator with an inner cylindrical conductive core for the submerged pumping of sodium in the cylindrical interstitial volume defined between the stator and core. The cylindrical interstitial volume is typically vertically oriented, and defines an inlet at the bottom and an outlet at the top. The outer stator generates upwardly conveyed toroidal magnetic fields, which fields convey preferably from the bottom of the pump to the top of the pump liquid sodium in the cold leg of a sodium cooled nuclear reactor. The outer cylindrical stator has a vertically disposed duct surrounded by alternately stacked layers of coil units and laminates. 14 figs.

  5. The chemistry of sodium chloride involvement in processes related to hot corrosion. [in gas turbine engines

    NASA Technical Reports Server (NTRS)

    Stearns, C. A.; Kohl, F. J.; Fryburg, G. C.

    1979-01-01

    Thermodynamic and mass transport calculations, and laboratory experiments elucidating the behavior of sodium chloride in combustion environments, in the deposition process, and in reactions with certain oxides on the surfaces of superalloys are summarized. It was found that some of the ingested salt is separated out of the air stream by the compressor. However, sodium chloride does pass from the compressor to the combustor where numerous chemical reactions take place. Here some of the salt is vaporized to yield gaseous sodium chloride molecules. Hydrogen and oxygen atoms present in the combustion products react with some sodium chloride to yield other gaseous species such as sodium, and a fraction of the salt remains as particulates. Both the gas phase and condensed sodium chloride can lead to sodium sulfate formation by various routes, all of which involve reaction with sulfur oxides and oxygen. In addition to contributing to the formation of sodium sulfate, the sodium chloride can contribute to corrosion directly.

  6. Effect of Bearing Cleaning on Long Term Bearing Life

    NASA Technical Reports Server (NTRS)

    Jett, Tim; Thom, R. L.

    1999-01-01

    For many years chlorofluorocarbon (CFC) based solvents, such as CFC-113 and 1,1,1, trichloroethane (TCA), were used as bearing cleaning solvents for space mechanism bearings. The 1995 ban on the production of ozone depleting chemicals (ODC) such as CFCs caused a change requiring the use of ODC-free cleaners for precision bearing cleaning. With this change the question arises; what effect if any do these new cleaners have on long term bearing life? The purpose of this study was to evaluate this effect. A one year test using 60 small electrical motors (two bearings per motor) was conducted in a high vacuum environment (2.0 x 10(exp -6) torr) at a temperature of 90 C. Prior to testing the bearings were cleaned with one of four cleaners. These cleaners included two aqueous based cleaners, a CFC based cleaner and supercritical carbon dioxide. Three space compatible greases were tested. After testing, the mass of each lubricated bearing was measured both pre and post test. Along with mass loss measurements a profilometer trace of each bearing was taken to measure post test wear of the bearings. In addition, the bearings were visually examined and analyzed using an optical microscope.

  7. Combination radial and thrust magnetic bearing

    NASA Technical Reports Server (NTRS)

    Blumenstock, Kenneth A. (Inventor)

    2002-01-01

    A combination radial and thrust magnetic bearing is disclosed that allows for both radial and thrust axes control of an associated shaft. The combination radial and thrust magnetic bearing comprises a rotor and a stator. The rotor comprises a shaft, and first and second rotor pairs each having respective rotor elements. The stator comprises first and second stator elements and a magnet-sensor disk. In one embodiment, each stator element has a plurality of split-poles and a corresponding plurality of radial force coils and, in another embodiment, each stator element does not require thrust force coils, and radial force coils are replaced by double the plurality of coils serving as an outer member of each split-pole half.

  8. Introgressive hybridization: brown bears as vectors for polar bear alleles.

    PubMed

    Hailer, Frank

    2015-03-01

    The dynamics and consequences of introgression can inform about numerous evolutionary processes. Biologists have therefore long been interested in hybridization. One challenge, however, lies in the identification of nonadmixed genotypes that can serve as a baseline for accurate quantification of admixture. In this issue of Molecular Ecology, Cahill et al. (2015) analyse a genomic data set of 28 polar bears, eight brown bears and one American black bear. Polar bear alleles are found to be introgressed into brown bears not only near a previously identified admixture zone on the Alaskan Admiralty, Baranof and Chichagof (ABC) Islands, but also far into the North American mainland. Elegantly contrasting admixture levels at autosomal and X chromosomal markers, Cahill and colleagues infer that male-biased dispersal has spread these introgressed alleles away from the Late Pleistocene contact zone. Compared to a previous study on the ABC Island population in which an Alaskan brown bear served as a putatively admixture-free reference, Cahill et al. (2015) utilize a newly sequenced Swedish brown bear as admixture baseline. This approach reveals that brown bears have been impacted by introgression from polar bears to a larger extent (up to 8.8% of their genome), than previously known, including the bear that had previously served as admixture baseline. No evidence for introgression of brown bear into polar bear is found, which the authors argue could be a consequence of selection. Besides adding new exciting pieces to the puzzle of polar/brown bear evolutionary history, the study by Cahill and colleagues highlights that wildlife genomics is moving from analysing single genomes towards a landscape genomics approach. PMID:25775930

  9. Gold-bearing skarns

    USGS Publications Warehouse

    Theodore, Ted G.; Orris, Greta J.; Hammerstrom, Jane M.; Bliss, James D.

    1991-01-01

    In recent years, a significant proportion of the mining industry's interest has been centered on discovery of gold deposits; this includes discovery of additional deposits where gold occurs in skarn, such as at Fortitude, Nevada, and at Red Dome, Australia. Under the classification of Au-bearing skarns, we have modeled these and similar gold-rich deposits that have a gold grade of at least 1 g/t and exhibit distinctive skarn mineralogy. Two subtypes, Au-skarns and byproduct Au-skarns, can be recognized on the basis of gold, silver, and base-metal grades, although many other geological factors apparently are still undistinguishable largely because of a lack of detailed studies of the Au-skarns. Median grades and tonnage for 40 Au-skarn deposits are 8.6 g/t Au, 5.0 g/t Ag, and 213,000 t. Median grades and tonnage for 50 byproduct and Au-skarn deposits are 3.7 g/t Au, 37 g/t Ag, and 330,000 t. Gold-bearing skarns are generally calcic exoskarns associated with intense retrograde hydrosilicate alteration. These skarns may contain economic amounts of numerous other commodities (Cu, Fe, Pb, Zn, As, Bi, W, Sb, Co, Cd, and S) as well as gold and silver. Most Au-bearing skarns are found in Paleozoic and Cenozoic orogenic-belt and island-arc settings and are associated with felsic to intermediate intrusive rocks of Paleozoic to Tertiary age. Native gold, electru, pyrite, pyrrhotite, chalcopyrite, arsenopyrite, sphalerite, galena, bismuth minerals, and magnetite or hematite are the most common opaque minerals. Gangue minerals typically include garnet (andradite-grossular), pyroxene (diopside-hedenbergite), wollastonite, chlorite, epidote, quartz, actinolite-tremolite, and (or) calcite.

  10. Linear magnetic bearings

    NASA Technical Reports Server (NTRS)

    Goldowskiy, M. P.

    1984-01-01

    A self regulating, nonfrictional, active magnetic bearing is disclosed which has an elongated cylindrical housing for containing a shaft type armature with quadrature positioned shaft position sensors and equidistantly positioned electromagnets located at one end of the housing. Each set of sensors is responsive to orthogonal displacement of the armature and is used to generate control signals to energize the electromagnets to center the armature. A bumper magnet assembly is located at one end of the housing for dampening any undesired axial movement of the armature or to axially move the armature either continuously or fixedly.

  11. Sodium hypochlorite poisoning

    MedlinePlus

    ... poisoning, especially if the product is mixed with ammonia. This article is for information only. Do NOT ... hypochlorite, which may cause severe injury. NEVER mix ammonia with sodium hypochlorite (bleach or bleach-containing products). ...

  12. Sodium bisulfate poisoning

    MedlinePlus

    ... in large amounts. This article discusses poisoning from swallowing sodium bisulfate. This article is for information only. ... Symptoms from swallowing more than a tablespoon of this acid may include: Burning pain in the mouth Chest pain from burns ...

  13. Sodium hydroxide poisoning

    MedlinePlus

    Agency for Toxic Substances and Disease Registry (ATSDR). Medical Management Guidelines for Sodium Hydroxide (NaOH) . Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service. Available at: www.atsdr.cdc. ...

  14. Sodium Polystyrene Sulfonate

    MedlinePlus

    ... comes as a suspension and as an oral powder for suspension to take by mouth. The suspension ... evenly.If you are taking sodium polystyrene sulfonate powder by mouth, mix the powder with 20 to ...

  15. Sodium hypochlorite dental accidents.

    PubMed

    Goswami, Mridula; Chhabra, Nidhi; Kumar, Gyanendra; Verma, Mahesh; Chhabra, Anuj

    2014-02-01

    Sodium hypochlorite is widely used in dentistry as an intra-canal irrigant, for debridement and to disinfect root canals. Although it is considered to be safe, serious mishap can result from its inappropriate use, and this has been reported infrequently in the literature. Two unusual cases of sodium hypochlorite toxicity and their successful non-surgical management are described in a 14-year-old girl and a 13-year-old boy. PMID:24090808

  16. Aerospace applications of magnetic bearings

    NASA Technical Reports Server (NTRS)

    Downer, James; Goldie, James; Gondhalekar, Vijay; Hockney, Richard

    1994-01-01

    Magnetic bearings have traditionally been considered for use in aerospace applications only where performance advantages have been the primary, if not only, consideration. Conventional wisdom has been that magnetic bearings have certain performance advantages which must be traded off against increased weight, volume, electric power consumption, and system complexity. These perceptions have hampered the use of magnetic bearings in many aerospace applications because weight, volume, and power are almost always primary considerations. This paper will review progress on several active aerospace magnetic bearings programs at SatCon Technology Corporation. The magnetic bearing programs at SatCon cover a broad spectrum of applications including: a magnetically-suspended spacecraft integrated power and attitude control system (IPACS), a magnetically-suspended momentum wheel, magnetic bearings for the gas generator rotor of a turboshaft engine, a vibration-attenuating magnetic bearing system for an airborne telescope, and magnetic bearings for the compressor of a space-rated heat pump system. The emphasis of these programs is to develop magnetic bearing technologies to the point where magnetic bearings can be truly useful, reliable, and well tested components for the aerospace community.

  17. Effect of Bearing Cleaning on Long Term Bearing Life

    NASA Technical Reports Server (NTRS)

    Jett, Timothy Raymond; Thom, Robert L.

    1998-01-01

    For many years chlorofluorocarbon (CFC ) based solvents, such as Freon and 1,1,1, Trichloroethane (TCA), were used as bearing cleaning solvents for space mechanisms. The 1995 ban on the production of ozone depleting chemicals (ODC) such as CFCs caused a change to new ODC-free cleaners for the precision bearing cleaning. With this change the question arises what effect if any do these new cleaners have on long term bearing life. The purpose of this study was to evaluate this effect. A one year test using 60 small electrical motors (two bearings per motor) was conducted in a high vacuum environment (2.0* 10(exp -6) torr) at a temperature of 90C. Prior to testing the bearings were cleaned with one of four cleaners. These cleaners included two aqueous based cleaners, a CFC based cleaner and supercritical carbon dioxide. Three space compatible greases were tested. After testing the mass of each lubricated bearing was measured both pre and post test. Along with mass loss measurements a profilometer trace of each bearing was taken to measure post test wear of the bearings. In addition the bearings were visually examined and analyzed using an optical microscope.

  18. Reduction in bearing size due to superconductors in magnetic bearings

    NASA Technical Reports Server (NTRS)

    Rao, Dantam K.; Lewis, Paul; Dill, James F.

    1991-01-01

    A design concept that reduces the size of magnetic bearings is assessed. The small size will enable magnetic bearings to fit into limited available bearing volume of cryogenic machinery. The design concept, called SUPERC, uses (high Tc) superconductors or high-purity aluminum conductors in windings instead of copper. The relatively high-current density of these conductors reduces the slot radial thickness for windings, which reduces the size of the bearings. MTI developed a sizing program called SUPERC that translates the high-current density of these conductors into smaller sized bearings. This program was used to size a superconducting bearing to carry a 500 lb. load. The sizes of magnetic bearings needed by various design concepts are as follows: SUPERC design concept = 3.75 in.; magnet-bias design concept = 5.25 in.; and all electromagnet design concept = 7.0 in. These results indicate that the SUPERC design concept can significantly reduce the size of the bearing. This reduction, in turn, reduces the weight and yields a lighter bearing. Since the superconductors have inherently near-zero resistance, they are also expected to save power needed for operation considerably.

  19. Series-hybrid bearing - An approach to extending bearing fatigue life at high speeds

    NASA Technical Reports Server (NTRS)

    Anderson, W. J.; Coe, H. H.; Fleming, D. P.; Parker, R. J.

    1971-01-01

    Fluid film bearing of hybrid device consists of orifice compensated annular thrust bearing and self-acting journal bearing. In series hybrid bearing, both ball bearing and annular thrust bearing carry full system thrust load, but two bearings share speed. Operation of system is stable and automatically fail-safe.

  20. Spin bearing retainer design optimization

    NASA Technical Reports Server (NTRS)

    Boesiger, Edward A.; Warner, Mark H.

    1991-01-01

    The dynamics behavior of spin bearings for momentum wheels (control-moment gyroscope, reaction wheel assembly) is critical to satellite stability and life. Repeated bearing retainer instabilities hasten lubricant deterioration and can lead to premature bearing failure and/or unacceptable vibration. These instabilities are typically distinguished by increases in torque, temperature, audible noise, and vibration induced by increases into the bearing cartridge. Ball retainer design can be optimized to minimize these occurrences. A retainer was designed using a previously successful smaller retainer as an example. Analytical methods were then employed to predict its behavior and optimize its configuration.

  1. Seismic evaluation of a large nuclear pump bearing using non-linear dynamic analysis

    SciTech Connect

    Huber, K.A.; Hugins, M.S.

    1983-01-01

    Hydrostatic bearings of a large vertical pump using sodium as the lubricant were critically examined to determine their ability to withstand seismic loads. Initial linear dynamics analyses predicted journal displacements to exceed bearing clearance by a ratio of 3:1. Equivalent time-history excitations were then developed from the response spectra to determine the number, magnitude, and duration of the bearing impact loads. Predicted loads were further reduced by 50% by modeling non-linear bearing characteristics normally present but not generally included in conventional linear analyses. Results are presented of the comprehensive design evaluation performed, based on these non-linear predictions, that assess stress, wear, and fatigue to demonstrate hydrostatic bearing integrity.

  2. Superconducting levitating bearing

    NASA Technical Reports Server (NTRS)

    Moon, Francis C. (Inventor)

    1996-01-01

    A superconducting bearing assembly includes a coil field source that may be superconducting and a superconducting structure. The coil field source assembly and superconducting structure are positioned so as to enable relative rotary movement therebetween. The structure and coil field source are brought to a supercooled temperature before a power supply induces a current in the coil field source. A Meissner-like effect is thereby obtained and little or no penetration of the field lines is seen in the superconducting structure. Also, the field that can be obtained from the superconducting coil is 2-8 times higher than that of permanent magnets. Since the magnetic pressure is proportioned to the square of the field, magnetic pressures from 4 to 64 times higher are achieved.

  3. The polar bear phenomena

    SciTech Connect

    Maw, P.K. ); Lane, M.T.

    1990-02-01

    Results from measuring the thermal profile of polar bear pelts, reflectiveness of the pelts, and total thermal conversion data lead to the conclusion that the pelts from an ultra-efficient thermal diode for solar-thermal conversion. The transfer of the thermal energy from the surface of the fur to the skin where it is absorbed cannot be thermal, and therefore must be radiative. This process must have an efficiency of better than 90:0090 percent to account for measured values. The radiative transfer process is not known at present. To understand it, a detailed knowledge of the microscopic parameters of the pelts must be obtained. This is the current thrust of the polar solar research. If the process can be understood and synthesized,it will provide a major breakthrough in the area of solar-thermal energy conversion.

  4. Technology gap analysis on sodium-cooled reactor fuel handling system supporting advanced burner reactor development.

    SciTech Connect

    Chikazawa, Y.; Farmer, M.; Grandy, C.; Nuclear Engineering Division

    2009-03-01

    The goals of the Global Nuclear Energy Partnership (GNEP) are to expand the use of nuclear energy to meet increasing global energy demand in an environmentally sustainable manner, to address nuclear waste management issues without making separated plutonium, and to address nonproliferation concerns. The advanced burner reactor (ABR) is a fast reactor concept which supports the GNEP fuel cycle system. Since the integral fast reactor (IFR) and advanced liquid-metal reactor (ALMR) projects were terminated in 1994, there has been no major development on sodium-cooled fast reactors in the United States. Therefore, in support of the GNEP fast reactor program, the history of sodium-cooled reactor development was reviewed to support the initiation of this technology within the United States and to gain an understanding of the technology gaps that may still remain for sodium fast reactor technology. The fuel-handling system is a key element of any fast reactor design. The major functions of this system are to receive, test, store, and then load fresh fuel into the core; unload from the core; then clean, test, store, and ship spent fuel. Major requirements are that the system must be reliable and relatively easy to maintain. In addition, the system should be designed so that it does not adversely impact plant economics from the viewpoints of capital investment or plant operations. In this gap analysis, information on fuel-handling operating experiences in the following reactor plants was carefully reviewed: EBR-I, SRE, HNPF, Fermi, SEFOR, FFTF, CRBR, EBR-II, DFR, PFR, Rapsodie, Phenix, Superphenix, KNK, SNR-300, Joyo, and Monju. The results of this evaluation indicate that a standardized fuel-handling system for a commercial fast reactor is yet to be established. However, in the past sodium-cooled reactor plants, most major fuel-handling components-such as the rotatable plug, in-vessel fuel-handling machine, ex-vessel fuel transportation cask, ex-vessel sodium-cooled storage

  5. Introduction to magnetic bearings

    NASA Astrophysics Data System (ADS)

    Skowronski, Lori; Bisese, Anne

    1993-04-01

    Multi-axis suspension has several advantages over single axis system, in that it provides control of an object with precision in two or three orthogonal axes. In this report, we discuss the primary use of magnetic-bearing suspension and it's relevance to what was formally known as NASA's Annular Suspension and Pointing System (ASPS). This system is an experimental pointing system with applications for the space shuttle and the space station programs. The objectives behind this magnetic suspension research project are to provide insight to the use of the ASPS configuration, to control the solar panels of the space station. This is important to maintain the correct position of the panels in relation to the sun and orbiting space station for the continuous supply of solar energy. Since the panels are suspended, they can be aligned with minimum outside interference. The approach of using magnetic suspension technology guarantees mechanical isolation since there are no contacting surfaces. This isolation reduces vibration transmission and mechanical wear which in turn extends the life of the payload and of the carrier. It should be noted that ASPS has a high pointing accuracy along the line of 0.01 arc-second. This research will be done in a laboratory setting by incorporating five bearing stations and one motion control station. We will attempt to suspend an object of dead weight similar to that of a solar panel. The long term applications may include deep-space navigation, fire control in weapon systems, and an improved mass transit system.

  6. Introduction to magnetic bearings

    NASA Technical Reports Server (NTRS)

    Skowronski, Lori; Bisese, Anne

    1993-01-01

    Multi-axis suspension has several advantages over single axis system, in that it provides control of an object with precision in two or three orthogonal axes. In this report, we discuss the primary use of magnetic-bearing suspension and it's relevance to what was formally known as NASA's Annular Suspension and Pointing System (ASPS). This system is an experimental pointing system with applications for the space shuttle and the space station programs. The objectives behind this magnetic suspension research project are to provide insight to the use of the ASPS configuration, to control the solar panels of the space station. This is important to maintain the correct position of the panels in relation to the sun and orbiting space station for the continuous supply of solar energy. Since the panels are suspended, they can be aligned with minimum outside interference. The approach of using magnetic suspension technology guarantees mechanical isolation since there are no contacting surfaces. This isolation reduces vibration transmission and mechanical wear which in turn extends the life of the payload and of the carrier. It should be noted that ASPS has a high pointing accuracy along the line of 0.01 arc-second. This research will be done in a laboratory setting by incorporating five bearing stations and one motion control station. We will attempt to suspend an object of dead weight similar to that of a solar panel. The long term applications may include deep-space navigation, fire control in weapon systems, and an improved mass transit system.

  7. Io's sodium cloud

    NASA Astrophysics Data System (ADS)

    Goldberg, B. A.; Garneau, G. W.; Lavoie, S. K.

    1984-11-01

    The first two-dimensional images of the source region of Io's neutral sodium cloud have been acquired by ground-based observation. Observed asymmetries in its spatial brightness distribution provide new evidence that the cloud is supplied by sodium that is ejected nonisotropically from Io or its atmosphere. Complementary, high-time-resolution, calibrated image sequences that give the first comprehensive picture of the variations of the fainter regions of the cloud extending more than 100,000 kilometers from Io were also obtained. These data demonstrate that the cloud exhibits a persistent systematic behavior coupled with Io's orbital position, a distinct 'east-west orbital asymmetry', a variety of spatial morphologies, and true temporal changes. The geometric stability of the sodium source is also indicated. Isolation of the cloud's temporal changes constitutes an important milestone toward its utilization as a long-term probe of Io and the inner Jovian magnetosphere.

  8. Sodium sulfur battery seal

    DOEpatents

    Mikkor, Mati

    1981-01-01

    This disclosure is directed to an improvement in a sodium sulfur battery construction in which a seal between various battery compartments is made by a structure in which a soft metal seal member is held in a sealing position by holding structure. A pressure applying structure is used to apply pressure on the soft metal seal member when it is being held in sealing relationship to a surface of a container member of the sodium sulfur battery by the holding structure. The improvement comprises including a thin, well-adhered, soft metal layer on the surface of the container member of the sodium sulfur battery to which the soft metal seal member is to be bonded.

  9. Getting Your Political Bearings

    ERIC Educational Resources Information Center

    Owen, Jane

    2007-01-01

    Being an instructional leader is important, but no one can be an instructional leader without a job. Political astuteness is key to survival in the principalship. The salient question, of course, is, How does one become politically astute? This process involves learning how to conscientiously and accurately keep a finger on the pulse of the…

  10. Service Lives Of Restored Bearings

    NASA Technical Reports Server (NTRS)

    Zaretsky, Erwin V.

    1988-01-01

    Rebuilt units last almost as long as new ones. Report describes theoretical and experiemental studies of lifetimes of restored ball and cylindrical-roller bearings. Results of this and related studies have implications of economy and safety in modern high-speed machinery, especially in aircraft industry, where inspection and rejection or replacing of bearings are new standard practice.

  11. Lubrication of rolling element bearings

    NASA Technical Reports Server (NTRS)

    Parker, R. J.

    1980-01-01

    This paper is a broad survey of the lubrication of rolling-element bearings. Emphasis is on the critical design aspects related to speed, temperature, and ambient pressure environment. Types of lubrication including grease, jets, mist, wick, and through-the-race are discussed. The paper covers the historical development, present state of technology, and the future problems of rolling-element bearing lubrication.

  12. Permanent-Magnet Meissner Bearing

    NASA Technical Reports Server (NTRS)

    Robertson, Glen A.

    1994-01-01

    Permanent-magnet meissner bearing features inherently stable, self-centering conical configuration. Bearing made stiffer or less stiff by selection of magnets, springs, and spring adjustments. Cylindrical permanent magnets with axial magnetization stacked coaxially on rotor with alternating polarity. Typically, rare-earth magnets used. Magnets machined and fitted together to form conical outer surface.

  13. Nonlinear control of magnetic bearings

    NASA Technical Reports Server (NTRS)

    Pradeep, A. K.; Gurumoorthy, R.

    1994-01-01

    In this paper we present a variety of nonlinear controllers for the magnetic bearing that ensure both stability and robustness. We utilize techniques of discontinuous control to design novel control laws for the magnetic bearing. We present in particular sliding mode controllers, time optimal controllers, winding algorithm based controllers, nested switching controllers, fractional controllers, and synchronous switching controllers for the magnetic bearing. We show existence of solutions to systems governed by discontinuous control laws, and prove stability and robustness of the chosen control laws in a rigorous setting. We design sliding mode observers for the magnetic bearing and prove the convergence of the state estimates to their true values. We present simulation results of the performance of the magnetic bearing subject to the aforementioned control laws, and conclude with comments on design.

  14. Space Station alpha joint bearing

    NASA Technical Reports Server (NTRS)

    Everman, Michael R.; Jones, P. Alan; Spencer, Porter A.

    1987-01-01

    Perhaps the most critical structural system aboard the Space Station is the Solar Alpha Rotary Joint which helps align the power generation system with the sun. The joint must provide structural support and controlled rotation to the outboard transverse booms as well as power and data transfer across the joint. The Solar Alpha Rotary Joint is composed of two transition sections and an integral, large diameter bearing. Alpha joint bearing design presents a particularly interesting problem because of its large size and need for high reliability, stiffness, and on orbit maintability. The discrete roller bearing developed is a novel refinement to cam follower technology. It offers thermal compensation and ease of on-orbit maintenance that are not found in conventional rolling element bearings. How the bearing design evolved is summarized. Driving requirements are reviewed, alternative concepts assessed, and the selected design is described.

  15. Effects of bearing cleaning and lube environment on bearing performance

    NASA Technical Reports Server (NTRS)

    Ward, Peter C.

    1995-01-01

    Running torque data of SR6 ball bearings are presented for different temperatures and speeds. The data are discussed in contrast to generally used torque prediction models and point out the need to obtain empirical data in critical applications. Also, the effects of changing bearing washing techniques from old, universally used CFC-based systems to CFC-free aqueous/alkaline solutions are discussed. Data on wettability, torque and lubricant life using SR3 ball bearings are presented. In general, performance is improved using the new aqueous washing techniques.

  16. Chlorite (sodium salt)

    Integrated Risk Information System (IRIS)

    Chlorite ( sodium salt ) ; CASRN 7758 - 19 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarc

  17. Dalapon, sodium salt

    Integrated Risk Information System (IRIS)

    Dalapon , sodium salt ; CASRN 75 - 99 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinoge

  18. Sodium sulfur battery seal

    DOEpatents

    Topouzian, Armenag

    1980-01-01

    This invention is directed to a seal for a sodium sulfur battery in which a flexible diaphragm sealing elements respectively engage opposite sides of a ceramic component of the battery which separates an anode compartment from a cathode compartment of the battery.

  19. Does salt increase thirst?

    PubMed

    Leshem, Micah

    2015-02-01

    Our diet is believed to be overly rich in sodium, and it is commonly believed that sodium intake increases drinking. Hence the concern of a possible contribution of dietary sodium to beverage intake which in turn may contribute to obesity and ill health. Here we examine whether voluntary, acute intake of a sodium load, as occurs in routine eating and snacking, increases thirst and drinking. We find that after ingesting 3.5 or 4.4 g NaCl (men) and 1.9 or 3.7 g (women) on nuts during 15 minutes, there is no increase in thirst or drinking of freely available water in the following 2 h compared with eating similar amounts of sugared or unflavored nuts. This suggests that routine ingestion of boluses of salt (~30-40% of daily intake for men, ~ 20-40% for women) does not increase drinking. Methodological concerns such as about nuts as vehicle for sodium suggest further research to establish the generalizability of this unexpected result. PMID:25447020

  20. Excess Sodium Tetraphenylborate and Intermediates Decomposition Studies

    SciTech Connect

    Barnes, M.J.; Peterson , R.A.

    1998-04-01

    The stability of excess amounts of sodium tetraphenylborate (NaTPB) in the In-Tank Precipitation (ITP) facility depends on a number of variables. Concentration of palladium, initial benzene, and sodium ion as well as temperature provide the best opportunities for controlling the decomposition rate. This study examined the influence of these four variables on the reactivity of palladium-catalyzed sodium tetraphenylborate decomposition. Also, single effects tests investigated the reactivity of simulants with continuous stirring and nitrogen ventilation, with very high benzene concentrations, under washed sodium concentrations, with very high palladium concentrations, and with minimal quantities of excess NaTPB. These tests showed the following.The testing demonstrates that current facility configuration does not provide assured safety of operations relative to the hazards of benzene (in particular to maintain the tank headspace below 60 percent of the lower flammability limit (lfl) for benzene generation rates of greater than 7 mg/(L.h)) from possible accelerated reaction of excess NaTPB. Current maximal operating temperatures of 40 degrees C and the lack of protection against palladium entering Tank 48H provide insufficient protection against the onset of the reaction. Similarly, control of the amount of excess NaTPB, purification of the organic, or limiting the benzene content of the slurry (via stirring) and ionic strength of the waste mixture prove inadequate to assure safe operation.

  1. Bearing Strengths of Some Wrought-aluminum Alloys

    NASA Technical Reports Server (NTRS)

    Moore, R L; Wescoat, C

    1943-01-01

    Although a number of investigations of the bearing strength of aluminum alloys have been made, the problem remains one of considerable interest to the aircraft industry. For this reason it has seemed advisable to make additional tests of the commonly used aircraft alloys in an effort to establish a better basis for the selection of allowable bearing values. Current design practice does not recognize the effect of edge distance upon bearing strengths, and for this reason edge distance was one of the principal variables considered in this investigation. The increasing emphasis being placed upon permanent set limitations makes it essential that more information on bearing yield phenomena be obtained. The object of this investigation was to determine bearing yield and ultimate strengths of the following aluminum alloy products: 17S-T, 24S-T, Alclad 24S-T, 24S-RT, 52S-0, 52S-1/2H, 52S-H, 53S-T, and 61S-T extrusions. Ratios of these bearing properties to tensile properties were also determined.

  2. Magnetic Bearings at Draper Laboratory

    NASA Technical Reports Server (NTRS)

    Kondoleon, Anthony S.; Kelleher, William P.; Possel, Peter D.

    1996-01-01

    Magnetic bearings, unlike traditional mechanical bearings, consist of a series of components mated together to form a stabilized system. The correct design of the actuator and sensor will provide a cost effective device with low power requirements. The proper choice of a control system utilizes the variables necessary to control the system in an efficient manner. The specific application will determine the optimum design of the magnetic bearing system including the touch down bearing. Draper for the past 30 years has been a leader in all these fields. This paper summarizes the results carried out at Draper in the field of magnetic bearing development. A 3-D radial magnetic bearing is detailed in this paper. Data obtained from recently completed projects using this design are included. One project was a high radial load (1000 pound) application. The second was a high speed (35,000 rpm), low loss flywheel application. The development of a low loss axial magnetic bearing is also included in this paper.

  3. SSME turbopump bearing analytical study

    NASA Technical Reports Server (NTRS)

    Kannel, J. W.; Merriman, T.

    1980-01-01

    Three shuttle pump bearings operating under severe overspeed and shut-down conditions are evaluated. The specific parameters investigated include outer race stresses, cage stresses, cage-race drag, bearing heating, and crush loading. A quasi-dynamic version of the BASDAP computer code was utilized which involved the calculation of ball-race forces (inner and outer), contact pressures, contact dimensions, and contact angles as a function of (1) axial load, (2) radial load, and (3) centrifugal load on the bearing. Generally, radial loads on the order of 13,300 N (3000 pounds) per bearing or 26,700 N (6000 pounds) per bearing pair, could be expected to cause severe problems to any of the bearings with a 17,800 N (4000 pounds) axial load. Further, when possible temperature excursions are considered, even a load of 8900 N (2000 pounds) may be excessive. However, high momentary radial loads with a 3800 N (850 pounds) axial load would not be anticipated to cause catastrophic failure of the fuel pump bearing.

  4. Hybrid Hydrostatic/Transient Roller Bearing Assembly

    NASA Technical Reports Server (NTRS)

    Justak, John F.

    1992-01-01

    Proposed bearing assembly for shaft of high-speed turbopump includes both hydrostatic and rolling-element bearings. Rolling-element bearing unloaded at high speed by centrifugal expansion of outer race and transient retainer.

  5. Two pad axially grooved hydrostatic bearing

    NASA Technical Reports Server (NTRS)

    San Andres, Luis A. (Inventor)

    1995-01-01

    A hydrostatic bearing having two axial grooves on opposite sides of the bearing for breaking the rotational symmetry in the dynamic force coefficients thus reducing the whirl frequency ratio and increasing the damping and stiffness of the hydrostatic bearing.

  6. 49 CFR 229.69 - Side bearings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ....69 Side bearings. (a) Friction side bearings with springs designed to carry weight may not have more than 25 percent of the springs in any one nest broken. (b) Friction side bearings may not be run...

  7. 49 CFR 229.69 - Side bearings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ....69 Side bearings. (a) Friction side bearings with springs designed to carry weight may not have more than 25 percent of the springs in any one nest broken. (b) Friction side bearings may not be run...

  8. 49 CFR 229.69 - Side bearings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ....69 Side bearings. (a) Friction side bearings with springs designed to carry weight may not have more than 25 percent of the springs in any one nest broken. (b) Friction side bearings may not be run...

  9. Fluid Film Bearing Code Development

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The next generation of rocket engine turbopumps is being developed by industry through Government-directed contracts. These turbopumps will use fluid film bearings because they eliminate the life and shaft-speed limitations of rolling-element bearings, increase turbopump design flexibility, and reduce the need for turbopump overhauls and maintenance. The design of the fluid film bearings for these turbopumps, however, requires sophisticated analysis tools to model the complex physical behavior characteristic of fluid film bearings operating at high speeds with low viscosity fluids. State-of-the-art analysis and design tools are being developed at the Texas A&M University under a grant guided by the NASA Lewis Research Center. The latest version of the code, HYDROFLEXT, is a thermohydrodynamic bulk flow analysis with fluid compressibility, full inertia, and fully developed turbulence models. It can predict the static and dynamic force response of rigid and flexible pad hydrodynamic bearings and of rigid and tilting pad hydrostatic bearings. The Texas A&M code is a comprehensive analysis tool, incorporating key fluid phenomenon pertinent to bearings that operate at high speeds with low-viscosity fluids typical of those used in rocket engine turbopumps. Specifically, the energy equation was implemented into the code to enable fluid properties to vary with temperature and pressure. This is particularly important for cryogenic fluids because their properties are sensitive to temperature as well as pressure. As shown in the figure, predicted bearing mass flow rates vary significantly depending on the fluid model used. Because cryogens are semicompressible fluids and the bearing dynamic characteristics are highly sensitive to fluid compressibility, fluid compressibility effects are also modeled. The code contains fluid properties for liquid hydrogen, liquid oxygen, and liquid nitrogen as well as for water and air. Other fluids can be handled by the code provided that the

  10. Io's Sodium Cloud (Clear Filter)

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This image of Jupiter's moon Io and its surrounding sky is shown in false color. It was taken at 5 hours 30 minutes Universal Time on Nov. 9, 1996 by the solid state imaging (CCD) system aboard NASA's Galileo spacecraft, using a clear filter whose wavelength range was approximately 400 to 1100 nanometers. This picture differs in two main ways from the green-yellow filter image of the same scene which was released yesterday.

    First, the sky around Io is brighter, partly because the wider wavelength range of the clear filter lets in more scattered light from Io's illuminated crescent and from Prometheus' sunlit plume. Nonetheless, the overall sky brightness in this frame is comparable to that seen through the green-yellow filter, indicating that even here much of the diffuse sky emission is coming from the wavelength range of the green-yellow filter (i.e., from Io's Sodium Cloud).

    The second major difference is that a quite large roundish spot has appeared in Io's southern hemisphere. This spot -- which has been colored red -- corresponds to thermal emission from the volcano Pele. The green-yellow filter image bears a much smaller trace of this emission because the clear filter is far more sensitive to those relatively long wavelengths where thermal emission is strongest.

    The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov.

  11. Random bearings and their stability.

    PubMed

    Mahmoodi Baram, Reza; Herrmann, Hans J

    2005-11-25

    Self-similar space-filling bearings have been proposed some time ago as models for the motion of tectonic plates and appearance of seismic gaps. These models have two features which, however, seem unrealistic, namely, high symmetry in the arrangement of the particles, and lack of a lower cutoff in the size of the particles. In this work, an algorithm for generating random bearings in both two and three dimensions is presented. Introducing a lower cutoff for the sizes of the particles, the instabilities of the bearing under an external force such as gravity, are studied. PMID:16384225

  12. Bears, Big and Little. Young Discovery Library Series.

    ERIC Educational Resources Information Center

    Pfeffer, Pierre

    This book is written for children 5 through 10. Part of a series designed to develop their curiosity, fascinate them and educate them, this volume describes: (1) the eight species of bears, including black bear, brown bear, grizzly bear, spectacled bear, sun bear, sloth bear, polar bear, and giant panda; (2) geographical habitats of bears; (3)…

  13. Does osteoarthritis of the knee also have a psychogenic component? Psycho-emotional treatment with a radio-electric device vs. intra-articular injection of sodium hyaluronate: an open-label, naturalistic study.

    PubMed

    Castagna, Alessandro; Rinaldi, Salvatore; Fontani, Vania; Aravagli, Lucia; Mannu, Piero; Margotti, Matteo Lotti

    2010-01-01

    This study is to compare, in patients suffering of knee joint disorder, the effects of intra-articular injection of Sodium Hyaluronate, and those of a treatment aiming at the improvement of the emotional status carried out by means of a Radio Electric Device (REAC). 30 subjects were divided into two groups: 15 who preferred a non-drugs approach (Group A) and 15 who preferred an infiltrative treatment (Group B). The evaluations were expressed for both pain level and knee bending and extension. Group A showed significant decrease in pain, stiffness, joint noises and intra-articular effusion, and significant improvement in motion range, without any patients worsening. 8 patients showed complete disappearance of pain in Visual Analog Pain Scale (VAS) evaluation, evident by a level of 0. The initial VAS results were between 8 and 4. One month after treatment's end, VAS results of the patients in Group A were between 3 and 0. Group B showed significant decrease in pain, stiffness, joint noises and intra-articular effusion, but no significant improvement in motion range; 2 of 15 patients showed worsening symptoms and no significant improvement in muscular hypotrophy. Initial VAS results were between 7 and 4. One month after treatment's end, VAS results were between 6 and 0. PMID:20578643

  14. High-Temperature, High-Load-Capacity Radial Magnetic Bearing

    NASA Technical Reports Server (NTRS)

    Provenza, Andrew; Montague, Gerald; Kascak, Albert; Palazzolo, Alan; Jansen, Ralph; Jansen, Mark; Ebihara, Ben

    2005-01-01

    A radial heteropolar magnetic bearing capable of operating at a temperature as high as 1,000 F (=540 C) has been developed. This is a prototype of bearings for use in gas turbine engines operating at temperatures and speeds much higher than can be withstood by lubricated rolling-element bearings. It is possible to increase the maximum allowable operating temperatures and speeds of rolling-element bearings by use of cooling-air systems, sophisticated lubrication systems, and rotor-vibration- damping systems that are subsystems of the lubrication systems, but such systems and subsystems are troublesome. In contrast, a properly designed radial magnetic bearing can suspend a rotor without contact, and, hence, without need for lubrication or for cooling. Moreover, a magnetic bearing eliminates the need for a separate damping system, inasmuch as a damping function is typically an integral part of the design of the control system of a magnetic bearing. The present high-temperature radial heteropolar magnetic bearing has a unique combination of four features that contribute to its suitability for the intended application: 1. The wires in its electromagnet coils are covered with an insulating material that does not undergo dielectric breakdown at high temperature and is pliable enough to enable the winding of the wires to small radii. 2. The processes used in winding and potting of the coils yields a packing factor close to 0.7 . a relatively high value that helps in maximizing the magnetic fields generated by the coils for a given supplied current. These processes also make the coils structurally robust. 3. The electromagnets are of a modular C-core design that enables replacement of components and semiautomated winding of coils. 4. The stator is mounted in such a manner as to provide stable support under radial and axial thermal expansion and under a load as large as 1,000 lb (.4.4 kN).

  15. Analysis of an arched outer-race ball bearing considering centrifugal forces

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.; Anderson, W. J.

    1972-01-01

    A Newton-Raphson method of iteration was used in evaluating the radial and axial projection of the distance between the ball center and the outer raceway groove curvature center (V and W). Fatigue life evaluations were made. The similar analysis of a conventional bearing can be directly obtained from the arched bearing analysis by simply letting the amount of arching be zero (g = 0) and not considering equations related to the unloaded half of the outer race. The analysis was applied to a 150-mm angular contact ball bearing. Results for life, contact loads, and angles are shown for a conventional bearing (g = 0) and two arched bearings (g = 0.127 mm (0.005 in.), and 0.254 mm (0.010 in.)). The results indicate that an arched bearing is highly desirable for high speed applications. In particular, for a DN value of 3 million (20,000 rpm) and an applied axial load of 4448 N (1000 lb), an arched bearing shows an improvement in life of 306 percent over that of a conventional bearing. At 4.2 million DN (28,000 rpm), the corresponding improvement is 340 percent. It was also found for low speeds, the arched bearing does not offer the advantages that it does for high speed applications.

  16. Sputter etching of hemispherical bearings

    NASA Technical Reports Server (NTRS)

    Schiesser, R. J.

    1972-01-01

    Technique was developed for fabricating three dimensional pumping grooves on gas bearings by sputter etching. Method eliminates problems such as groove nonuniformity, profile, and finish, which are associated with normal grooving methods.

  17. Mixed-mu superconducting bearings

    DOEpatents

    Hull, J.R.; Mulcahy, T.M.

    1998-03-03

    A mixed-mu superconducting bearing is disclosed including a ferrite structure disposed for rotation adjacent a stationary superconductor material structure and a stationary permanent magnet structure. The ferrite structure is levitated by said stationary permanent magnet structure. 9 figs.

  18. Mixed-mu superconducting bearings

    DOEpatents

    Hull, John R.; Mulcahy, Thomas M.

    1998-01-01

    A mixed-mu superconducting bearing including a ferrite structure disposed for rotation adjacent a stationary superconductor material structure and a stationary permanent magnet structure. The ferrite structure is levitated by said stationary permanent magnet structure.

  19. A Passive Magnetic Bearing Flywheel

    NASA Technical Reports Server (NTRS)

    Siebert, Mark; Ebihara, Ben; Jansen, Ralph; Fusaro, Robert L.; Morales, Wilfredo; Kascak, Albert; Kenny, Andrew

    2002-01-01

    A 100 percent passive magnetic bearing flywheel rig employing no active control components was designed, constructed, and tested. The suspension clothe rotor was provided by two sets of radial permanent magnetic bearings operating in the repulsive mode. The axial support was provided by jewel bearings on both ends of the rotor. The rig was successfully operated to speeds of 5500 rpm, which is 65 percent above the first critical speed of 3336 rpm. Operation was not continued beyond this point because of the excessive noise generated by the air impeller and because of inadequate containment in case of failure. Radial and axial stiffnesses of the permanent magnetic bearings were experimentally measured and then compared to finite element results. The natural damping of the rotor was measured and a damping coefficient was calculated.

  20. ATM CMG bearing failure analysis

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The cause or causes for the failure of ATM CMG S/N 5 (Skylab 1) and the anomalies associated with ATM CMG S/N 6 (Skylab 2) were investigated. Skylab telemetry data were reviewed and presented in the form of parameter distributions. The theory that the problems were caused by marginal bearing lubrication was studied along with the effects of orbital conditions on lubricants. Bearing tests were performed to investigate the effect of lubricant or lack of lubricant in the ATM CMG bearings and the dispersion and migration of the lubricant. The vacuum and weightless conditions of space were simulated in the bearing tests. Analysis of the results of the tests conducted points to inadequate lubrication as the predominant factor causing the failure of ATM CMG S/N 5 (Skylab 1) and the anomalies associated with ATM CMG S/N 6 (Skylab 2).

  1. High-temperature bearing lubricants

    NASA Technical Reports Server (NTRS)

    Anderson, W. J.; Parker, R. J.; Zaretsky, E. V.

    1968-01-01

    Synthetic paraffinic oil lubricates ball bearings at temperatures in the 600 degrees F range. The lubricant contains antiwear and antifoam additives, is thermally stable in the high temperature range, but requires protection from oxygen.

  2. Flex bearing UUEC, volume 2

    NASA Technical Reports Server (NTRS)

    Clapper, M. L.

    1993-01-01

    This volume, Volume 2, of this Flex Bearing UUEC Final Report documents findings and data pertaining to Team B's tasks. Team B was organized as one of two sub-teams of the Unplanned/Unintended Event or Condition (UUEC) board established per InterOffice Memorandum (IOM) A100-FY93-072. Team A determined the cause of the unacceptable unbonds (referred to as 'heat-affect' unbonds), including the initial, light rust film, in the FSM #3 flex bearing was overheating of the Forward End Ring (FER) during cure, specifically in zone 8 of the mold. Team A's findings are documented in Volume 1 of this report. Team B developed flight rationale for existing bearings, based on absence or presence of an unpropitious unbond condition like that in FSM #3's flex bearing.

  3. Myrmecophagy by Yellowstone grizzly bears

    USGS Publications Warehouse

    Mattson, D.J.

    2001-01-01

    I used data collected during a study of radio-marked grizzly bears (Ursus arctos horribilis) in the Yellowstone region from 1977 to 1992 to investigate myrmecophagy by this population. Although generally not an important source of energy for the bears (averaging 8 mm long) nested in logs over small ants (6 mm long) nested under stones. Optimal conditions for consumption of ants occurred on the warmest sites with ample substrate suitable for ant nests. For ants in mounds, this occurred at low elevations at non-forested sites. For ants in logs, this occurred at low elevations or on southerly aspects where there was abundant, large-diameter, well-decomposed woody debris under an open forest canopy. Grizzly bears selected moderately decomposed logs 4a??5 dm in diameter at midpoint. Ants will likely become a more important food for Yellowstone's grizzly bears as currently important foods decline, owing to disease and warming of the regional climate.

  4. Lateral dampers for thrust bearings

    NASA Technical Reports Server (NTRS)

    Hibner, D. H.; Szafir, D. R.

    1985-01-01

    The development of lateral damping schemes for thrust bearings was examined, ranking their applicability to various engine classes, selecting the best concept for each engine class and performing an in-depth evaluation. Five major engine classes were considered: large transport, military, small general aviation, turboshaft, and non-manrated. Damper concepts developed for evaluation were: curved beam, constrained and unconstrained elastomer, hybrid boost bearing, hydraulic thrust piston, conical squeeze film, and rolling element thrust face.

  5. Polyurethane retainers for ball bearings

    NASA Technical Reports Server (NTRS)

    Christy, R. I.

    1973-01-01

    Evaluation of a new ball bearing retainer material is reported. A special composite polyurethane foam ball retainer has been developed that has virtually zero wear, is chemically inert to hydrocarbon lubricants, and stores up to 60 times as much lubricant per unit volume as the most commonly used retainer material, cotton phenolic. This new retainer concept shows promise of years of ball bearing operation without reoiling, based on life testing in high vacuum.

  6. High-speed motion picture camera experiments of cavitation in dynamically loaded journal bearings

    NASA Technical Reports Server (NTRS)

    Jacobson, B. O.; Hamrock, B. J.

    1982-01-01

    A high-speed camera was used to investigate cavitation in dynamically loaded journal bearings. The length-diameter ratio of the bearing, the speeds of the shaft and bearing, the surface material of the shaft, and the static and dynamic eccentricity of the bearing were varied. The results reveal not only the appearance of gas cavitation, but also the development of previously unsuspected vapor cavitation. It was found that gas cavitation increases with time until, after many hundreds of pressure cycles, there is a constant amount of gas kept in the cavitation zone of the bearing. The gas can have pressures of many times the atmospheric pressure. Vapor cavitation bubbles, on the other hand, collapse at pressures lower than the atmospheric pressure and cannot be transported through a high-pressure zone, nor does the amount of vapor cavitation in a bearing increase with time. Analysis is given to support the experimental findings for both gas and vapor cavitation.

  7. ENHANCING DAMAGE VISIBILITY ON METALLIC BEARING SURFACES: A SIMPLE TECHNIQUE FOR PHOTOGRAPHY AND VIEWING

    PubMed Central

    Heiner, Anneliese D.; Kruger, Karen M.; Baer, Thomas E.; Brown, Thomas D.

    2012-01-01

    Damage to metallic bearing surfaces typically involves scratches, scrapes, metal transfer, and organic deposits. This damage can cause accelerated wear of the opposing surface and subsequent implant failure. Photography and viewing of metallic bearing surfaces, for documenting this damage, is hindered by optical reflectivity. This note demonstrates a simple, practical technique for metallic bearing surface photography and viewing that minimizes this reflectivity problem, that does not involve any modification of the bearing surface, and that allows for improved observation and documentation of overall damage. When the metallic bearing surface is placed within a tube of translucent material, the appearance of damage on that bearing surface is dramatically enhanced, showing up against a smooth, even background with excellent contrast and with fine detail achievable. PMID:23333257

  8. Sodium disorders in the elderly.

    PubMed Central

    Tareen, Naureen; Martins, David; Nagami, Glenn; Levine, Barton; Norris, Keith C.

    2005-01-01

    Disorders of sodium imbalance are commonly encountered in clinical practice and can have a substantial impact on the prognosis of the patient. These disorders are more common in the elderly. Sodium disorders can cause serious neurologic symptoms and even death, particularly among hospitalized patients. The identification of sodium abnormalities and appropriate clinical intervention are critical for improving patient outcomes. Early recognition of hyponatremia and hypernatremia can provide a clue to an underlying disorder. In this update, we have summarized age-related homeostatic changes that impair sodium balance, medications that alter salt and water handling, and the recognition and management of sodium disorders in elderly patients. PMID:15712785

  9. SSME Long-life Bearings

    NASA Technical Reports Server (NTRS)

    Butner, M. F.; Murphy, B. T.

    1986-01-01

    Hybrid hydrostatic/ball bearings for LH2 and LO2 service in turbopumps were studied as a means of improving speed and life capabilities. Four hybrid bearing configurations were designed with emphasis on achieving maximum stiffness and damping. Parallel load bearings were tested at steady-state and transient conditions with LH2 (externally fed) and LN2 (internally fed). The hydrostatic elements were tested with Freon 113 for empirical determination of dynamic characteristics. Tests using an eccentric journal for loading showed the externally and internally fed hydrostatic bearings to have significant separated coefficients of direct stiffness and damping. For the internally fed bearing, the strongly speed-dependent cross-coupling stiffness arising from fluid swirl, along with significant cross-coupling damping, resulted in low net effective stiffness and damping. The test method used can produce separated coefficients with a sufficiently elliptic journal orbit; otherwise, only net effective coefficients combining direct and cross-coupling terms can be determined. Testing with nonsynchronous excitation is recommended to avoid this restriction. Investigation of hard materials, including ceramics, is recommended as a means of eliminating the need for the rolling bearing for startup and shutdown support. The testing was performed in 1984 (LH2), 1985 (LN2) and 1985-86 (Freon).

  10. Designing Rolling-Element Bearings

    NASA Technical Reports Server (NTRS)

    Moore, James D., Jr.

    2007-01-01

    Bearing Analysis Tool (BAT) is a computer program for designing rolling-element bearings for cryogenic turbomachines. BAT provides a graphical user interface (GUI) that guides the entry of data to develop mathematical models of bearings. The GUI breaks model data into logical subsets that are entered through logic-driven input screens. The software generates a threedimensional graphical model of a bearing as the data are entered. Most dataentry errors become immediately obvious in the graphical model. BAT provides for storage of all the data on a shaft/bearing system, enabling the creation of a library of proven designs. Data from the library can be transferred to subsequent projects by use of simple cut-and-paste routines. BAT includes a library of temperature- dependent cryogenic bearing-material properties for use in the mathematical models. BAT implements algorithms that (1) enable the user to select combinations of design and/or operating-condition parameters, and then (2) automatically optimize the design by performing trade studies over all of the parameter combinations. This feature enables optimization over a large trade space in a fraction of the time taken when using prior bearingmodel software.

  11. Gimbal bearing design considerations and friction control

    NASA Technical Reports Server (NTRS)

    Kramer, N. R.

    1979-01-01

    The design considerations of bearing selection, bearing fits, bearing installation, and thermal control are discussed for a gimbal with a high stiffness, low friction torque requirement. Tradeoffs between a quad set of small diameter spread apart or a large diameter bearing pair resulted in a cleaner, lighter, stiffer unit with the latter selection. Bearing fits were designed to eliminate clearances with tolerances of .00127 mm 00005 in) on the bearing shafts and housings. The problems in metrology are discussed and a perferred technique for measurement of small cross-section bearings described. A technique for installation to assure proper seating of the bearing is offered. Where transient thermal conditions are involved, a method of controlling bearing friction by active control of bearing temperature gradients including the use of bearing unload test curves is described.

  12. Testing and Lubrication for Single Race Bearings

    SciTech Connect

    Steinhoff, R.G.

    1998-03-04

    Three ES and H-compatible lubricants (Environment, Safety and Health) for single race bearing applications and one hybrid-material single race bearings were evaluated and compared against single race bearings with trichlorotrifluoroethane (Freon) deposition of low molecular weight polytetrafluoroethylene (PTFE) bearing lubricant extracted from Vydax{trademark}. Vydax is a product manufactured by DuPont consisting of various molecular weights of PTFE suspended in trichlorotrifluoroethane (Freon), which is an ozone-depleting solvent. Vydax has been used as a bearing lubricant in stronglink mechanisms since 1974. Hybrid bearings with silicon nitride balls and molded glass-nylon-Teflon retainers, bearings lubricated with titanium carbide (TiC) on the balls, bearings lubricated with sputtered MoS{sub 2} on races and retainers, and bearings lubricated with electrophoretically deposited MoS{sub 2} were evaluated. The bearings were maintained in a preloaded state in bearing cartridges during cycling and vibration tests. Bearings with electrophoretically deposited MoS{sub 2} performed as well as bearings lubricated with Vydax and were the best performing candidate. All candidates were suitable for low preload applications. Bearings with TiC coated balls and bearings lubricated with sputtered MoS{sub 2} on the races and retainers performed well at high preloads, though not as well as bearings lubricated with electrophoretic deposition of MoS{sub 2}. Bearings with silicon nitride balls were not suitable for high preload applications.

  13. 21 CFR 184.1733 - Sodium benzoate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... GRAS § 184.1733 Sodium benzoate. (a) Sodium benzoate is the chemical benzoate of soda (C7H5NaO2), produced by the neutralization of benzoic acid with sodium bicarbonate, sodium carbonate, or sodium... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sodium benzoate. 184.1733 Section 184.1733...

  14. 21 CFR 184.1736 - Sodium bicarbonate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Sodium bicarbonate. 184.1736 Section 184.1736 Food... Specific Substances Affirmed as GRAS § 184.1736 Sodium bicarbonate. (a) Sodium bicarbonate (NaHCO3, CAS Reg. No. 144-55-8) is prepared by treating a sodium carbonate or a sodium carbonate and sodium...

  15. 21 CFR 184.1736 - Sodium bicarbonate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sodium bicarbonate. 184.1736 Section 184.1736 Food... GRAS § 184.1736 Sodium bicarbonate. (a) Sodium bicarbonate (NaHCO3, CAS Reg. No. 144-55-8) is prepared by treating a sodium carbonate or a sodium carbonate and sodium bicarbonate solution with...

  16. 21 CFR 184.1736 - Sodium bicarbonate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium bicarbonate. 184.1736 Section 184.1736 Food... Specific Substances Affirmed as GRAS § 184.1736 Sodium bicarbonate. (a) Sodium bicarbonate (NaHCO3, CAS Reg. No. 144-55-8) is prepared by treating a sodium carbonate or a sodium carbonate and sodium...

  17. 21 CFR 184.1736 - Sodium bicarbonate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Sodium bicarbonate. 184.1736 Section 184.1736 Food... Specific Substances Affirmed as GRAS § 184.1736 Sodium bicarbonate. (a) Sodium bicarbonate (NaHCO3, CAS Reg. No. 144-55-8) is prepared by treating a sodium carbonate or a sodium carbonate and sodium...

  18. 21 CFR 201.64 - Sodium labeling.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... this section). (e) The term very low sodium may be used in the labeling of OTC drug products intended.... (f) The term low sodium may be used in the labeling of OTC drug products intended for oral ingestion... the term sodium. (h) The terms sodium free, very low sodium, and low sodium shall be in print size...

  19. 77 FR 70423 - Black Bear Hydro Partners, LLC and Black Bear Development Holdings, LLC and Black Bear SO, LLC...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-26

    ... Energy Regulatory Commission Black Bear Hydro Partners, LLC and Black Bear Development Holdings, LLC and Black Bear SO, LLC; Notice of Application for Partial Transfer of Licenses, and Soliciting Comments and Motions To Intervene On October 25, 2012, Black Bear Hydro Partners, LLC, sole licensee (transferor)...

  20. Wall pressure exerted by hydrogenation of sodium aluminum hydride.

    SciTech Connect

    Perras, Yon E.; Dedrick, Daniel E.; Zimmerman, Mark D.

    2009-06-01

    Wall pressure exerted by the bulk expansion of a sodium aluminum hydride bed was measured as a function of hydrogen content. A custom apparatus was designed and loaded with sodium alanates at densities of 1.0, 1.1, and 1.16 g/cc. Four complete cycles were performed to identify variations in measured pressure. Results indicated poor correlation between exerted pressure and hydrogen capacity of the sodium alanate beds. Mechanical pressure due to the hydrogenation of sodium alanates does not influence full-scale system designs as it falls within common design factors of safety. Gas pressure gradients within the porous solid were identified and may limit reaction rates, especially for high aspect ratio beds.

  1. High Temperature Superconducting Bearings for Lunar Telescope Mounts

    NASA Technical Reports Server (NTRS)

    Lamb, Mark; BuiMa, Ki; Cooley, Rodger; Mackey, Daniel; Meng, Ruling; Chu, Ching Wu; Chu, Wei Kan; Chen, Peter C.; Wilson, Thomas

    1995-01-01

    A telescope to be installed on the lunar surface in the near future must work in a cold and dusty vacuum environment for long periods without on site human maintenance. To track stars, the drive mechanism must be capable of exceedingly fine steps and repeatability. Further, the use of lightweight telescopes for obvious economic benefits burdens the requirement for stable support and rotation. Conventional contact bearings and gear drives have numerous failure modes under such a restrictive and harsh environment. However, hybrid superconducting magnetic bearings (HSMB) fit in naturally. These bearings are stable, light, passive, and essentially frictionless, allowing high precision electronic positioning control. By passive levitation, the HSMB does not wear out and requires neither maintenance nor power. A prototype illustrating the feasibility of this application is presented.

  2. Emersion Testing of Phenix Reactor Components From Liquid Sodium

    SciTech Connect

    Baque, F.

    2002-07-01

    The life extension of the Phenix LMFR involved the inspection of reactor vessel internal structures: among other techniques, a visual inspection was performed of the above core structure, fuel assembly heads and upper components. To make this inspection possible, a partial draining of the main vessel from primary liquid sodium was carried out (sodium at 180 and argon cover at 150 ). The test program aimed at obtaining further knowledge on the process of wetting of sodium - as pure metal - on Phenix Plant assembly heads - made of stainless steel -, as well as on the internal structure welding, was carried out from November 1998 to January 1999. The main results were as follows: - the sodium meniscus measured during sodium lowering against the non-wet vertical structures reaches 10 mm in height. On wetted structures, it reaches only 5.3 mm. - when sodium level decreases, the process if very regular. However, re-flooding is carried out in stages. - a difference of 0.2 mm between two heads altitudes is enough to observe successively each of the heads. - the quality of sodium does not modify the wetting process (in the range of cold trap temperature: 110-140 deg. C). - the influence of lighting is important. - the visibility limit of emerging electro-eroded cracks (from 0.17 to 1.0 mm) is at 0.20 mm. - the visibility of a horizontal welding, machined or not, is good when the lighting is sufficient. - the superficial flow of sodium only modifies the wetting process for the closest heads. A final test allowed to observe that the global inclination of the assembly head mock-up does not modify the wetting process. These experimental results were part of the feasibility demonstration of the visual inspection within the actual Phenix Plant that was undertaken in 2001. (authors)

  3. Bear reintroduction: Lessons and challenges

    USGS Publications Warehouse

    Clark, Joseph D.; Huber, Djuro; Servheen, Christopher

    2002-01-01

    Reintroduction is defined as an attempt to establish a species in an area that was once part of its historical range, but from which it has been extirpated or become extinct. Historically, one of the most successful programs was the reintroduction of 254 American black bears (Ursus americanus) from Minnesota to the Interior Highlands of Arkansas in the 1960s; that population has grown to >2,500 today. More recent efforts have involved fewer but better monitored animals and have sometimes employed techniques to improve site fidelity and survival. In Pennsylvania, for example, pregnant female American black bears were successfully translocated from winter dens, the premise being that the adult females would be less likely to return because of the presence of young cubs. That winter-release technique was compared to summer trapping and release in Tennessee; winter releases resulted in greater survival and reduced post-release movements. Homing has not been a problem for small numbers of brown bears (Ursus arctos) reintroduced to the Cabinet-Yaak ecosystem in Montana and Idaho and to the mountains of Austria and France. Reintroduction success appears to be correlated with translocation distance and is greater for subadults and females. As with any small population, reintroduced bear populations are susceptible to environmental variation and stochastic demographic and genetic processes. Although managers have focused on these biological barriers, sociopolitical impediments to bear reintroduction are more difficult to overcome. Poor public acceptance and understanding of bears are the main reasons some reintroduction programs have been derailed. Consequently, the public should be involved in the reintroduction process from the outset; overcoming negative public perceptions about bear reintroduction will be our greatest challenge.

  4. Hydrostatic liquid-bearing for precision gyro

    NASA Technical Reports Server (NTRS)

    Sgambati, R. J.

    1971-01-01

    Unit with 2W power increase and slightly larger overall dimensions performs as well as or better than its gas-bearing counterpart. Liquid-bearings are built by reworking serviceable gas-bearing components /sleeves, endplates, and cylinders/. Hydrostatic bearing is self-centered, requiring no magnetic suspension or centering jewel.

  5. 36 CFR 13.1236 - Bear orientation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Bear orientation. 13.1236... Developed Area § 13.1236 Bear orientation. All persons visiting the BCDA must receive an NPS-approved Bear Orientation. Failure to receive an NPS-approved Bear Orientation is prohibited....

  6. 36 CFR 13.1236 - Bear orientation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Bear orientation. 13.1236... Developed Area § 13.1236 Bear orientation. All persons visiting the BCDA must receive an NPS-approved Bear Orientation. Failure to receive an NPS-approved Bear Orientation is prohibited....

  7. 36 CFR 13.1236 - Bear orientation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Bear orientation. 13.1236... Developed Area § 13.1236 Bear orientation. All persons visiting the BCDA must receive an NPS-approved Bear Orientation. Failure to receive an NPS-approved Bear Orientation is prohibited....

  8. 49 CFR 229.69 - Side bearings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Side bearings. 229.69 Section 229.69....69 Side bearings. (a) Friction side bearings with springs designed to carry weight may not have more than 25 percent of the springs in any one nest broken. (b) Friction side bearings may not be run...

  9. 36 CFR 13.1236 - Bear orientation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Bear orientation. 13.1236... Developed Area § 13.1236 Bear orientation. All persons visiting the BCDA must receive an NPS-approved Bear Orientation. Failure to receive an NPS-approved Bear Orientation is prohibited....

  10. 49 CFR 229.69 - Side bearings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Side bearings. 229.69 Section 229.69....69 Side bearings. (a) Friction side bearings with springs designed to carry weight may not have more than 25 percent of the springs in any one nest broken. (b) Friction side bearings may not be run...

  11. 36 CFR 13.1236 - Bear orientation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Bear orientation. 13.1236... Developed Area § 13.1236 Bear orientation. All persons visiting the BCDA must receive an NPS-approved Bear Orientation. Failure to receive an NPS-approved Bear Orientation is prohibited....

  12. Investigations of a bearing fault detector for railroad bearings

    NASA Technical Reports Server (NTRS)

    Wilson, D. S.; Frarey, J. L.

    1975-01-01

    The laboratory tests are described which were conducted on new and damaged bearings to determine the feasibility of using high-frequency vibration as a diagnostic tool. A high-frequency band pass filter and demodulator was assembled to permit field measurements of the high-frequency vibrations. Field tests were conducted on an actual truck and on an axle assembly run in a grease test rig. These field tests were directed toward demonstration of the suitability and capabilities of the high-frequency technique for field application. Two specific areas of field application were identified as being cost effective for railroad use. One area is the examination of railroad roller bearings at a derailment site, and the second is as a wayside detector to supplement present hot box detectors for defective roller bearings.

  13. Sodium channel Nax is a regulator in epithelial sodium homeostasis.

    PubMed

    Xu, Wei; Hong, Seok Jong; Zhong, Aimei; Xie, Ping; Jia, Shengxian; Xie, Zhong; Zeitchek, Michael; Niknam-Bienia, Solmaz; Zhao, Jingling; Porterfield, D Marshall; Surmeier, D James; Leung, Kai P; Galiano, Robert D; Mustoe, Thomas A

    2015-11-01

    The mechanisms by which the epidermis responds to disturbances in barrier function and restores homeostasis are unknown. With a perturbation of the epidermal barrier, water is lost, resulting in an increase in extracellular sodium concentration. We demonstrate that the sodium channel Nax functions as a sodium sensor. With increased extracellular sodium, Nax up-regulates prostasin, which results in activation of the sodium channel ENaC, resulting in increased sodium flux and increased downstream mRNA synthesis of inflammatory mediators. Nax is present in multiple epithelial tissues, and up-regulation of its downstream genes is found in hypertrophic scars. In animal models, blocking Nax expression results in improvement in scarring and atopic dermatitis-like symptoms, both of which are pathological conditions characterized by perturbations in barrier function. These findings support an important role for Nax in maintaining epithelial homeostasis. PMID:26537257

  14. Hydrostatic bearings for a turbine fluid flow metering device

    DOEpatents

    Fincke, J.R.

    1982-05-04

    A rotor assembly fluid metering device has been improved by development of a hydrostatic bearing fluid system which provides bearing fluid at a common pressure to rotor assembly bearing surfaces. The bearing fluid distribution system produces a uniform film of fluid between bearing surfaces and allows rapid replacement of bearing fluid between bearing surfaces, thereby minimizing bearing wear and corrosion. 3 figs.

  15. Hydrostatic bearings for a turbine fluid flow metering device

    DOEpatents

    Fincke, James R.

    1982-01-01

    A rotor assembly fluid metering device has been improved by development of a hydrostatic bearing fluid system which provides bearing fluid at a common pressure to rotor assembly bearing surfaces. The bearing fluid distribution system produces a uniform film of fluid between bearing surfaces and allows rapid replacement of bearing fluid between bearing surfaces, thereby minimizing bearing wear and corrosion.

  16. Cryogenic Magnetic Bearing Test Facility (CMBTF)

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The Cryogenic Magnetic Bearing Test Facility (CMBTF) was designed and built to evaluate compact, lightweight magnetic bearings for use in the SSME's (space shuttle main engine) liquid oxygen and liquid hydrogen turbopumps. State of the art and tradeoff studies were conducted which indicated that a hybrid permanent magnet bias homopolar magnetic bearing design would be smaller, lighter, and much more efficient than conventional industrial bearings. A test bearing of this type was designed for the test rig for use at both room temperature and cryogenic temperature (-320 F). The bearing was fabricated from state-of-the-art materials and incorporated into the CMBTF. Testing at room temperature was accomplished at Avcon's facility. These preliminary tests indicated that this magnetic bearing is a feasible alternative to older bearing technologies. Analyses showed that the hybrid magnetic bearing is one-third the weight, considerably smaller, and uses less power than previous generations of magnetic bearings.

  17. Application of foil bearings to helium turbocompressor

    SciTech Connect

    Chen, H.Ming; Howarth, R.; Bernard, Geren; Theilacker, Jay C.; Soyars, William M.; /Fermilab

    2001-01-01

    Hydrodynamic gas-lubricated foil bearings are ideal for machinery that operates at high speed or in extreme-temperature environments. As motors and generators run at higher speeds with more torque capacity, the need for commonly available, robust, high-speed, low-loss foil bearings is clear. This paper presents an application example of the successful replacement of a tape-type bearing for a bump-type bearing in a helium turbocompressor. Both bearing types are described, as are the steps involved in design and fabrication of the bump bearing, and results of comparison tests between the original and replacement bearings. Methods to analyze bump-type foil bearings with commercially available software are reviewed to further emphasize the inherent simplicity of these bearings. By providing the engineering community with the understanding needed to successfully apply foil bearings, the authors hope that the benefits and true potential of this technology will finally be realized.

  18. Superconductor bearings, flywheels and transportation

    NASA Astrophysics Data System (ADS)

    Werfel, F. N.; Floegel-Delor, U.; Rothfeld, R.; Riedel, T.; Goebel, B.; Wippich, D.; Schirrmeister, P.

    2012-01-01

    This paper describes the present status of high temperature superconductors (HTS) and of bulk superconducting magnet devices, their use in bearings, in flywheel energy storage systems (FESS) and linear transport magnetic levitation (Maglev) systems. We report and review the concepts of multi-seeded REBCO bulk superconductor fabrication. The multi-grain bulks increase the averaged trapped magnetic flux density up to 40% compared to single-grain assembly in large-scale applications. HTS magnetic bearings with permanent magnet (PM) excitation were studied and scaled up to maximum forces of 10 kN axially and 4.5 kN radially. We examine the technology of the high-gradient magnetic bearing concept and verify it experimentally. A large HTS bearing is tested for stabilizing a 600 kg rotor of a 5 kWh/250 kW flywheel system. The flywheel rotor tests show the requirement for additional damping. Our compact flywheel system is compared with similar HTS-FESS projects. A small-scale compact YBCO bearing with in situ Stirling cryocooler is constructed and investigated for mobile applications. Next we show a successfully developed modular linear Maglev system for magnetic train operation. Each module levitates 0.25t at 10 mm distance during one-day operation without refilling LN2. More than 30 vacuum cryostats containing multi-seeded YBCO blocks are fabricated and are tested now in Germany, China and Brazil.

  19. PRESSURE DEVELOPMENT IN SEALED CONTAINERS WITH PLUTONIUM BEARING MATERIALS

    SciTech Connect

    Duffey, J.; Livingston, R.

    2010-02-01

    Gas generation by plutonium-bearing materials in sealed containers has been studied. The gas composition and pressure are determined over periods from months to years. The Pu-bearing materials studied represent those produced by all of the major processes used by DOE in the processing of plutonium and include the maximum amount of water (0.5% by weight) allowed by DOE's 3013 Standard. Hydrogen generation is of high interest and the Pu-bearing materials can be classed according to how much hydrogen is generated. Hydrogen generation by high-purity plutonium oxides packaged under conditions typical for actual 3013 materials is minimal, with very low generation rates and low equilibrium pressures. Materials with chloride salt impurities have much higher hydrogen gas generation rates and result in the highest observed equilibrium hydrogen pressures. Other materials such as those with high metal oxide impurities generate hydrogen at rates in between these extremes. The fraction of water that is converted to hydrogen gas as equilibrium is approached ranges from 0% to 25% under conditions typical of materials packaged to the 3013 Standard. Generation of both hydrogen and oxygen occurs when liquid water is present. The material and moisture conditions that result in hydrogen and oxygen generation for high-purity plutonium oxide and chloride salt-bearing plutonium oxide materials have been characterized. Other gases that are observed include nitrous oxide, carbon dioxide, carbon monoxide, and methane.

  20. Does every US smoker bear the same cigarette tax?

    PubMed Central

    Xu, Xin; Malarcher, Ann; O’Halloran, Alissa; Kruger, Judy

    2015-01-01

    Aims To evaluate state cigarette excise tax pass-through rates for selected price-minimizing strategies. Design Multivariate regression analysis of current smokers from a stratified, national, dual-frame telephone survey. Setting United States. Participants A total of 16 542 adult current smokers aged 18 years or older. Measurements Cigarette per pack prices paid with and without coupons were obtained for pack versus carton purchase, use of generic brands versus premium brands, and purchase from Indian reservations versus outside Indian reservations. Findings The average per pack prices paid differed substantially by price-minimizing strategy. Smokers who used any type of price-minimizing strategies paid substantially less than those who did not use these strategies (P < 0.05). Premium brand users who purchased by pack in places outside Indian reservations paid the entire amount of the excise tax, together with an additional premium of 7–10 cents per pack for every $1 increase in excise tax (pass-through rate of 1.07–1.10, P < 0.05). In contrast, carton purchasers, generic brand users or those who were likely to make their purchases on Indian reservations paid only 30–83 cents per pack for every $1 tax increase (pass-through rate of 0.30–0.83, P < 0.05). Conclusions Many smokers in the United States are able to avoid the full impact of state excise tax on cost of smoking by buying cartons, using generic brands and buying from Indian reservations. PMID:24861973

  1. Sodium homeostasis with chronic sodium loading in preascitic cirrhosis

    PubMed Central

    Wong, F; Liu, P; Blendis, L

    2001-01-01

    BACKGROUND—Preascitic cirrhotic patients receiving 200 mmol of sodium daily for seven days remain in positive sodium balance. Thereafter, sodium handling is unknown.
AIM—To assess renal sodium handling in preascitic cirrhosis on a high sodium diet for five weeks.
METHODS—Sixteen biopsy proven preascitic cirrhotics were assessed at weekly intervals for five weeks on a diet of 200 mmol sodium/day using a daily weight diary and weekly 24 hour urinary sodium estimations. Fasting supine neurohormone levels were measured at baseline and weekly for five weeks while haemodynamics were measured at baseline and at five weeks.
RESULTS—The daily diet of 200 mmol of sodium resulted in weight gain and a positive sodium balance for three weeks, associated with significant suppression of plasma renin activity and aldosterone levels, and a significant rise in plasma atrial natriuretic peptide levels (p<0.05). Patients' weights plateaued during week 4, associated with complete sodium balance and significant suppression of plasma noradrenaline levels (p<0.05). This was followed by a negative sodium balance and weight loss, and finally complete sodium balance, again despite a mean net gain of 2.3 (0.3) kg, associated with a return of plasma renin activity and aldosterone levels to within normal ranges. The lack of increase in central blood volume in addition to the persistent increase in plasma atrial natriuretic peptide levels indicated that residual volume expansion, consequent to persistent weight gain, was distributed on the venous side of the circulation. No free fluid was seen on repeat abdominal ultrasound after five weeks.
CONCLUSION—Preascitic cirrhotics have a natriuretic "escape" after three weeks on high sodium dietary intake, associated with elevated plasma atrial natriuretic peptide levels and suppression of the renin-angiotensin-aldosterone system. With continued suppressed sympathetic activity, preascitics re-establish complete sodium balance

  2. Mercury's sodium exosphere

    NASA Astrophysics Data System (ADS)

    Schmidt, Carl A.

    In this dissertation I examine the properties and origins of the most energetic component of Mercury's atmosphere and how it couples to the planet's magnetosphere and space environment. Mercury' s atmosphere consists of particles liberated from its surface that follow ballistic, collisionless trajectories under the influence of gravity and solar radiation pressure. This tenuous atmosphere can be classified as an exosphere where the exobase boundary is the planet's surface. To explain how this exosphere is sustained, a number of theories have been presented: (1) thermal evaporation from the hot surface; (2) photo-desorption of surface materials by UV solar radiation; (3) sputtering by plasma surface interactions; and (4) vaporization of the surface by micro-meteorite impacts. Using a 3-dimensional numerical model, I determine the role each source has in populating the exosphere. New observations of Mercury's escaping atmosphere are presented using novel imaging techniques in which sodium acts as a tracer to identify atmospheric sources. I discuss the implications of these measurements for our understanding of the physical processes at work in the exosphere, and provide a foundation for modeling such processes. For the first time, this work quantifies the variability in the loss of Mercury's sodium as a seasonal effect. My observations show that atmospheric escape can, at times, exceed 1024 Na atoms/s, nearly twice the highest rate previously reported. By forward modeling Mercury' s atmospheric escape, I place new constraints on the source properties and eliminate the prevailing theory that the escaping tail is sputtered from the surface by solar wind ions. The MESSENGER spacecraft has recently discovered that sodium is distributed unevenly over the surface and that the magnetosphere is offset from the planet's center. Using the first model to include these effects, I demonstrate the magnetosphere's influence upon exospheric sources by simulating asymmetries observed

  3. Magnetometry with mesospheric sodium

    PubMed Central

    Higbie, James M.; Rochester, Simon M.; Patton, Brian; Holzlöhner, Ronald; Bonaccini Calia, Domenico; Budker, Dmitry

    2011-01-01

    Measurement of magnetic fields on the few 100-km length scale is significant for many geophysical applications including mapping of crustal magnetism and ocean circulation measurements, yet available techniques for such measurements are very expensive or of limited accuracy. We propose a method for remote detection of magnetic fields using the naturally occurring atomic sodium-rich layer in the mesosphere and existing high-power lasers developed for laser guide star applications. The proposed method offers a dramatic reduction in cost and opens the way to large-scale, parallel magnetic mapping and monitoring for atmospheric science, navigation, and geophysics. PMID:21321235

  4. Magnetometry with mesospheric sodium.

    PubMed

    Higbie, James M; Rochester, Simon M; Patton, Brian; Holzlöhner, Ronald; Bonaccini Calia, Domenico; Budker, Dmitry

    2011-03-01

    Measurement of magnetic fields on the few 100-km length scale is significant for many geophysical applications including mapping of crustal magnetism and ocean circulation measurements, yet available techniques for such measurements are very expensive or of limited accuracy. We propose a method for remote detection of magnetic fields using the naturally occurring atomic sodium-rich layer in the mesosphere and existing high-power lasers developed for laser guide star applications. The proposed method offers a dramatic reduction in cost and opens the way to large-scale, parallel magnetic mapping and monitoring for atmospheric science, navigation, and geophysics. PMID:21321235

  5. [Controlled weight bearing after osteosynthesis].

    PubMed

    Perren, T; Matter, P

    1993-01-01

    Patient compliance with postoperative partial weight bearing can be a difficult management problem. The problem may be intentional or unintentional. There is no objective way to assess the amount of weight placed on the lower extremity by the patient. It is our clinical suspicion that patients place more weight than is desirable on the effected limb. There are few reports in the literature on this topic. One study has confirmed our suspicion of poor patient compliance with postoperative weight bearing. Our goal is to develop a system to accurately assess weight bearing and to improve this aspect of postoperative fracture care. Through an active feedback device we hope to improve patient education and understanding. We plan to study the clinical applications of using a pressure sensitive shoe insert device. Our ultimate goal is to improve upon the present device and to study the clinical application of there use. PMID:8123330

  6. 'Dodo' and 'Baby Bear' Trenches

    NASA Technical Reports Server (NTRS)

    2008-01-01

    NASA's Phoenix Mars Lander's Surface Stereo Imager took this image on Sol 11 (June 5, 2008), the eleventh day after landing. It shows the trenches dug by Phoenix's Robotic Arm. The trench on the left is informally called 'Dodo' and was dug as a test. The trench on the right is informally called 'Baby Bear.' The sample dug from Baby Bear will be delivered to the Phoenix's Thermal and Evolved-Gas Analyzer, or TEGA. The Baby Bear trench is 9 centimeters (3.1 inches) wide and 4 centimeters (1.6 inches) deep.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  7. Sodium bicarbonate in chemical flooding: Part 1: Topical report. [Sodium bicarbonate and sodium carbonate

    SciTech Connect

    Peru, D.A.; Lorenz, P.B.

    1987-07-01

    To compare oil recovery and alkali consumption in alkaline flooding using sodium bicarbonate with other alkaline agents, coreflooding experiments were performed in turn with viscosified sodium bicarbonate and viscosified sodium carbonate solutions. Oil recovery was monitored, and the effluent brine from these corefloods was analyzed for silicon, aluminum, pH, and total inorganic carbon. The results indicate that viscosified sodium bicarbonate recovered more of the asphaltic Cerro-Negro crude than of the less asphaltic Wilmington crude oil. The recovery efficiency using the viscosified sodium carbonate was similar for the two crudes. For both crudes, the percent oil recovery using viscosified sodium carbonate was slightly higher than that using the viscosified sodium bicarbonate. Mineral dissolution and decrease in pH were found to be greater in corefloods using viscosified sodium carbonate. Total inorganic carbon recovery can be obtained in corefloods with either agent, provided that a sufficient water drive follows the chemical slug. Long-term experiments were performed by recirculating alkaline solutions through oil-free, unfired Berea sandstone to monitor the rock/alkali interactions. The experimental results indicate an eight-fold decrease in quartz dissolution by sodium bicarbonate compared with sodium carbonate. Moderate magnesium solubility was observed at the pH of the bicarbonate solution. Low solubility of magnesium and aluminum at the pH of the carbonate indicates the possible formation of precipitates. In these experiments 13% of the carbonate was converted to bicarbonate. Total alkalinity was not significantly decreased with either agent. 18 refs., 5 tabs.

  8. Sodium Benzoate for Treatment of Hepatic Encephalopathy

    PubMed Central

    Misel, Michael L.; Patton, Heather; Mendler, Michel

    2013-01-01

    Hepatic encephalopathy (HE) is a serious but usually reversible neuropsychiatric complication of cirrhosis, inborn errors of metabolism involving disorders of the urea cycle, and noncirrhotic portosystemic shunting that most commonly arises from a transjugular intrahepatic portosystemic shunting procedure. Symptoms can include alterations in cognitive function, neuromuscular activity, and consciousness, as well as sleep disorders and mood changes. HE is associated with significant morbidity and mortality and, if not properly treated, will lead to increased hospital admissions and healthcare costs. Although the standard therapies of lactulose and rifaximin (Xifaxan, Salix) are effective for most patients, these drugs may be associated with significant adverse effects and expense and, in some patients, inadequate therapeutic response. A need for adjunctive therapies exists. Drugs that target serum and tissue ammonia metabolism and elimination may be important adjuncts to drugs that reduce ammonia production and absorption from the gastrointestinal tract for patients with severe or persistent overt symptoms of HE. Sodium benzoate is an inexpensive adjunctive agent that can be used in addition to lactulose and rifaximin and may provide an option for some select patients with refractory HE who have failed to respond to standard therapies or who cannot afford them. Although sodium benzoate does not share the same adverse effect profiles of standard therapies for HE, its efficacy has not been well established. Given the significant dose-dependent sodium content of this therapy, it may not be appropriate for patients with significant fluid retention or kidney dysfunction. PMID:24711766

  9. Iron Phosphate Glasses for Vitrifying DOE High Priority Nuclear Wastes

    SciTech Connect

    Kim, C.W.; Day, D.E.

    2004-03-29

    Iron phosphate glasses have been studied as an alternative glass for vitrifying Department of Energy (DOE) high priority wastes. The high priority wastes were the Low Activity Waste (LAW) and the High Level Waste (HLW) with high chrome content stored at Hanford, WA, and the Sodium Bearing Waste (SBW) stored at the Idaho National Engineering and Environmental Laboratory. These wastes were recommended by Tanks Focus Area since they were expected to require special attention when vitrified in borosilicate glasses. All three of these wastes have been successfully vitrified in iron phosphate glasses at waste loadings ranging from a low of 32 wt% for the high sulfate LAW to 40 wt% for the SBW to a high of 75 wt% for the high chrome HLW. In addition to these desirable high waste loadings, the iron phosphate glasses were easily melted, typically between 950 and 1200 C, in less than 4 hours in commercial refractory oxide containers. It is noteworthy that the chemical durability of both glassy and deliberately crystallized iron phosphate wasteforms not only met, but significantly exceeded, all current DOE chemical durability requirements as measured by the Product Consistency Test (PCT) and Vapor Hydration Test (VHT). The high waste loading, low melting temperature, rapid furnace throughput (short melting time) and their outstanding chemical durability could significantly accelerate the clean up effort and reduce the time and cost of vitrifying these high priority wastes.

  10. Air bearing vacuum seal assembly

    DOEpatents

    Booth, Rex

    1978-01-01

    An air bearing vacuum seal assembly capable of rotating at the speed of several thousand revolutions per minute using an air cushion to prevent the rotating and stationary parts from touching, and a two stage differential pumping arrangement to maintain the pressure gradient between the air cushion and the vacuum so that the leak rate into the vacuum is, for example, less than 1 .times. 10.sup.-4 Pa m.sup.3 /s. The air bearing vacuum seal has particular application for mounting rotating targets to an evacuated accelerator beam tube for bombardment of the targets with high-power charged particle beams in vacuum.

  11. An Assessment of Gas Foil Bearing Scalability and the Potential Benefits to Civilian Turbofan Engines

    NASA Technical Reports Server (NTRS)

    Bruckner, Robert J.

    2010-01-01

    Over the past several years the term oil-free turbomachinery has been used to describe a rotor support system for high speed turbomachinery that does not require oil for lubrication, damping, or cooling. The foundation technology for oil-free turbomachinery is the compliant foil bearing. This technology can replace the conventional rolling element bearings found in current engines. Two major benefits are realized with this technology. The primary benefit is the elimination of the oil lubrication system, accessory gearbox, tower shaft, and one turbine frame. These components account for 8 to 13 percent of the turbofan engine weight. The second benefit that compliant foil bearings offer to turbofan engines is the capability to operate at higher rotational speeds and shaft diameters. While traditional rolling element bearings have diminished life, reliability, and load capacity with increasing speeds, the foil bearing has a load capacity proportional to speed. The traditional applications for foil bearings have been in small, lightweight machines. However, recent advancements in the design and manufacturing of foil bearings have increased their potential size. An analysis, grounded in experimentally proven operation, is performed to assess the scalability of the modern foil bearing. This analysis was coupled to the requirements of civilian turbofan engines. The application of the foil bearing to larger, high bypass ratio engines nominally at the 120 kN (approx.25000 lb) thrust class has been examined. The application of this advanced technology to this system was found to reduce mission fuel burn by 3.05 percent.

  12. Slow Sodium: An Oral Slowly Released Sodium Chloride Preparation

    PubMed Central

    Clarkson, E. M.; Curtis, J. R.; Jewkes, R. J.; Jones, B. E.; Luck, V. A.; de Wardener, H. E.; Phillips, N.

    1971-01-01

    The use of a slowly released oral preparation of sodium chloride is described. It was given to patients and athletes to treat or prevent acute and chronic sodium chloride deficiency. Gastrointestinal side effects were not encountered after the ingestion of up to 500 mEq in one day or 200 mEq in 10 minutes. PMID:5569979

  13. A Simple Quantitative Synthesis: Sodium Chloride from Sodium Carbonate.

    ERIC Educational Resources Information Center

    Gold, Marvin

    1988-01-01

    Describes a simple laboratory procedure for changing sodium carbonate into sodium chloride by adding concentrated HCl to cause the reaction and then evaporating the water. Claims a good stoichiometric yield can be obtained in one three-hour lab period. Suggests using fume hood for the reaction. (ML)

  14. Slow sodium: an oral slowly released sodium chloride preparation.

    PubMed

    Clarkson, E M; Curtis, J R; Jewkes, R J; Jones, B E; Luck, V A; de Wardener, H E; Phillips, N

    1971-09-11

    The use of a slowly released oral preparation of sodium chloride is described. It was given to patients and athletes to treat or prevent acute and chronic sodium chloride deficiency. Gastrointestinal side effects were not encountered after the ingestion of up to 500 mEq in one day or 200 mEq in 10 minutes. PMID:5569979

  15. GENOTOXICITY STUDIES OF SODIUM DICHLOROACETATE AND SODIUM TRICHLOROACETATE

    EPA Science Inventory

    The genotoxic properties of sodium dichloroacetate (DCA) and sodium trichloroacetate (TCA)were evaluated in several short-term in vitro and in vivo assays. Neither compound was mutagenic in tester strain TA102 in the Salmonella mutagenicity assay. Both DCA and TCA were weak induc...

  16. Vibrations of Hybrid Ceramic Ball Bearings

    NASA Astrophysics Data System (ADS)

    Ohta, H.; Kobayashi, K.

    1996-05-01

    Hybrid ceramic ball bearings with silicone nitride balls and steel rings were tested, and the vibration characteristics were compared with those of conventional steel ball bearings. In this study, two types of hybrid ceramic ball bearings and two types of conventional steel ball bearings were used as test bearings. The test bearings were operated under several rotational speeds and axial loads. The radial and the axial vibrations on the outer ring of each test bearing were detected by an accelerometer. The vibrations were examined by using an FFT analyzer. From the experimental results, analysis and discussion, the vibration characteristics of hybrid ceramic ball bearings, compared with those of conventional steel ball bearings, are explained.

  17. Wave Journal Bearing. Part 1: Analysis

    NASA Technical Reports Server (NTRS)

    Dimofte, Florin

    1995-01-01

    A wave journal bearing concept features a waved inner bearing diameter of the non-rotating bearing side and it is an alternative to the plain journal bearing. The wave journal bearing has a significantly increased load capacity in comparison to the plain journal bearing operating at the same eccentricity. It also offers greater stability than the plain circular bearing under all operating conditions. The wave bearing's design is relatively simple and allows the shaft to rotate in either direction. Three wave bearings are sensitive to the direction of an applied stationary side load. Increasing the number of waves reduces the wave bearing's sensitivity to the direction of the applied load relative to the wave. However, the range in which the bearing performance can be varied decreases as the number of waves increases. Therefore, both the number and the amplitude of the waves must be properly selected to optimize the wave bearing design for a specific application. It is concluded that the stiffness of an air journal bearing, due to hydrodynamic effect, could be doubled and made to run stably by using a six or eight wave geometry with a wave amplitude approximately half of the bearing radial clearance.

  18. Dietary intake of sodium chloride in the rat influences [3H]nitrendipine binding to adrenal glomerulosa cell membranes but does not alter binding to vascular smooth muscle membranes.

    PubMed Central

    Schiebinger, R J

    1985-01-01

    Angiotensin II-stimulated secretion by adrenal glomerulosa cells and contraction by vascular smooth muscle (VSM) are dependent on calcium influx through membrane calcium channels. We have examined the hypothesis that the altered responsiveness of adrenal glomerulosa cells and VSM to angiotensin II during NaCl restriction may be associated with a change in membrane calcium channel number. To test this hypothesis, female rats were placed on a high or low NaCl diet. On the 14th day, membranes were prepared from the zona glomerulosa, aorta, mesenteric artery, and uterus. [3H]Nitrendipine binding was used to monitor calcium channel number. The [3H]nitrendipine binding capacity was observed to be higher in the zona glomerulosa during NaCl restriction than during high NaCl intake (83 +/- 18 vs. 49 +/- 9 fmol/mg protein, P less than 0.025, n = 6 paired experiments). The binding capacities of [3H]nitrendipine on the low and high NaCl diet were similar in the mesenteric artery (10 +/- 1 vs. 9 +/- 1 fmol/mg protein, n = 8), aorta (33 +/- 5 vs. 35 +/- 8 fmol/mg protein, n = 5), or uterus (87 +/- 15 vs. 85 +/- 16 fmol/mg protein, n = 4), respectively. The dissociation constants of [3H]nitrendipine binding did not differ on a low or high NaCl intake in the zona glomerulosa (0.84 +/- .12 vs. 0.79 +/- .10 nM), mesenteric artery (0.82 +/- .06 vs. 83 +/- .05 nM), aorta (0.90 +/- .11 vs. 0.92 +/- .12 nM), or uterus (0.55 +/- .12 vs. 0.56 +/- .10 nM), respectively. We conclude that the blunted response of VSM to angiotensin II during NaCl restriction is best explained by the previously reported lower number of angiotensin II receptors since calcium channel number does not change. In the adrenal glomerulosa cell, NaCl restriction is associated with a higher number of membrane calcium channels and angiotensin II receptors. The increase in calcium channel number may reflect the influence of an unknown factor(s) believed to be necessary for the full expression of the adrenal glomerulosa

  19. Fuzzy control of magnetic bearings

    NASA Technical Reports Server (NTRS)

    Feeley, J. J.; Niederauer, G. M.; Ahlstrom, D. J.

    1991-01-01

    The use of an adaptive fuzzy control algorithm implemented on a VLSI chip for the control of a magnetic bearing was considered. The architecture of the adaptive fuzzy controller is similar to that of a neural network. The performance of the fuzzy controller is compared to that of a conventional controller by computer simulation.

  20. Inserts Automatically Lubricate Ball Bearings

    NASA Technical Reports Server (NTRS)

    Hager, J. A.

    1983-01-01

    Inserts on ball-separator ring of ball bearings provide continuous film of lubricant on ball surfaces. Inserts are machined or molded. Small inserts in ball pockets provide steady supply of lubricant. Technique is utilized on equipment for which maintenance is often poor and lubrication interval is uncertain, such as household appliances, automobiles, and marine engines.

  1. High performance rolling element bearing

    NASA Technical Reports Server (NTRS)

    Bursey, Jr., Roger W. (Inventor); Olinger, Jr., John B. (Inventor); Owen, Samuel S. (Inventor); Poole, William E. (Inventor); Haluck, David A. (Inventor)

    1993-01-01

    A high performance rolling element bearing (5) which is particularly suitable for use in a cryogenically cooled environment, comprises a composite cage (45) formed from glass fibers disposed in a solid lubricant matrix of a fluorocarbon polymer. The cage includes inserts (50) formed from a mixture of a soft metal and a solid lubricant such as a fluorocarbon polymer.

  2. Gradient Tempering Of Bearing Races

    NASA Technical Reports Server (NTRS)

    Parr, Richardson A.

    1991-01-01

    Gradient-tempering process increases fracture toughness and resistance to stress-corrosion cracking of ball-bearing races made of hard, strong steels and subject to high installation stresses and operation in corrosive media. Also used in other applications in which local toughening of high-strength/low-toughness materials required.

  3. Intelligent Engine Systems: Bearing System

    NASA Technical Reports Server (NTRS)

    Singh, Arnant P.

    2008-01-01

    The overall requirements necessary for sensing bearing distress and the related criteria to select a particular rotating sensor were established during the phase I. The current phase II efforts performed studies to evaluate the Robustness and Durability Enhancement of the rotating sensors, and to design, and develop the Built-in Telemetry System concepts for an aircraft engine differential sump. A generic test vehicle that can test the proposed bearing diagnostic system was designed, developed, and built. The Timken Company, who also assisted with testing the GE concept of using rotating sensors for the differential bearing diagnostics during previous phase, was selected as a subcontractor to assist General Electric (GE) for the design, and procurement of the test vehicle. A purchase order was prepared to define the different sub-tasks, and deliverables for this task. The University of Akron was selected to provide the necessary support for installing, and integrating the test vehicle with their newly designed test facility capable of simulating the operating environment for the planned testing. The planned testing with good and damaged bearings will be on hold pending further continuation of this effort during next phase.

  4. Satellite monitoring of black bear.

    NASA Technical Reports Server (NTRS)

    Craighead, J. J.; Craighead, F. C., Jr.; Varney, J. R.; Cote, C. E.

    1971-01-01

    Description of a feasibility experiment recently performed to test the use of a satellite system for telemetering environmental and physiological data from the winter den of a 'hibernating' black bear, Ursus americanus. The instrumentation procedure and evaluations of the equipment performance and sensory data obtained are discussed in detail.

  5. Sodium Recycle Economics for Waste Treatment Plant Operations

    SciTech Connect

    Sevigny, Gary J.; Poloski, Adam P.; Fountain, Matthew S.

    2008-08-31

    Sodium recycle at the Hanford Waste Treatment Plant (WTP) would reduce the number of glass canisters produced, and has the potential to significantly reduce the cost to the U.S. Department of Energy (DOE) of treating the tank wastes by hundreds of millions of dollars. The sodium, added in the form of sodium hydroxide, was originally added to minimize corrosion of carbon-steel storage tanks from acidic reprocessing wastes. In the baseline Hanford treatment process, sodium hydroxide is required to leach gibbsite and boehmite from the high level waste (HLW) sludge. In turn, this reduces the amount of HLW glass produced. Currently, a significant amount of additional sodium hydroxide will be added to the process to maintain aluminate solubility at ambient temperatures during ion exchange of cesium. The vitrification of radioactive waste is limited by sodium content, and this additional sodium mass will increase low-activity waste-glass mass. An electrochemical salt-splitting process, based on sodium-ion selective ceramic membranes, is being developed to recover and recycle sodium hydroxide from high-salt radioactive tank wastes in DOE’s complex. The ceramic membranes are from a family of materials known as sodium (Na)—super-ionic conductors (NaSICON)—and the diffusion of sodium ions (Na+) is allowed, while blocking other positively charged ions. A cost/benefit evaluation was based on a strategy that involves a separate caustic-recycle facility based on the NaSICON technology, which would be located adjacent to the WTP facility. A Monte Carlo approach was taken, and several thousand scenarios were analyzed to determine likely economic results. The cost/benefit evaluation indicates that 10,000–50,000 metric tons (MT) of sodium could be recycled, and would allow for the reduction of glass production by 60,000–300,000 MT. The cost of the facility construction and operation was scaled to the low-activity waste (LAW) vitrification facility, showing cost would be

  6. Antimicrobial and antioxidant effects of sodium acetate, sodium lactate, and sodium citrate in refrigerated sliced salmon

    PubMed Central

    Sallam, Khalid Ibrahim

    2007-01-01

    This study was carried out to evaluate the microbiological quality and lipid oxidation of fresh salmon slices treated by dipping in 2.5% (w/v) aqueous solution of sodium acetate (NaA), sodium lactate (NaL), or sodium citrate (NaC) and stored at 1 °C. The results revealed that these salts were efficient (P < 0.05) against the proliferation of various categories of spoilage microorganisms; including aerobic and psychrotrophic populations, Pseudomonas spp., H2S-producing bacteria, lactic acid bacteria, and Enterobacteriaceae. The general order of antibacterial activity of the different organic salts used was; sodium acetate > sodium lactate > sodium citrate. Lipid oxidation, as expressed by peroxide value (PV) and thiobarbituric acid (TBA) value, was significantly (P < 0.05) delayed in NaA- and NaC-treated samples. The antioxidant activity followed the order: NaC > NaA > NaL. The shelf life of the treated products was extended by 4–7 days more than that of the control. Therefore, sodium acetate, sodium lactate, and sodium citrate can be utilized as safe organic preservatives for fish under refrigerated storage. PMID:17471315

  7. Sodium dichromate expedited response action assessment

    SciTech Connect

    Not Available

    1993-09-01

    The US Environmental Protection Agency (EPA) and Washington Department of Ecology (Ecology) recommended that the US Department of Energy (DOE) perform an expedited response action (ERA) for the Sodium Dichromate Barrel Disposal Landfill. The ERA lead regulatory agency is Ecology and EPA is the support agency. The ERA was categorized as non-time-critical, which required preparation of an engineering evaluation and cost analysis (EE/CA). The EE/CA was included in the ERA proposal. The EE/CA is a rapid, focused evaluation of available technologies using specific screening factors to assess feasibility, appropriateness, and cost. The ERA goal is to reduce the potential for any contaminant migration from the landfill to the soil column, groundwater, and Columbia River. Since the Sodium Dichromate Barrel Disposal Landfill is the only waste site within the operable unit, the removal action may be the final remediation of the 100-IU-4 Operable Unit. This ERA process started in March 1992. The ERA proposal went through a parallel review process with Westinghouse Hanford Company (WHC), DOE Richland Operations (RL), EPA, Ecology, and a 30-day public comment period. Ecology and EPA issued an Action Agreement Memorandum in March 1993 (Appendix A). The memorandum directed excavation of all anomalies and disposal of the collected materials at the Hanford Site Central Landfill. Primary field activities were completed by the end of April 1993. Final waste disposal of a minor quantity of hazardous waste was completed in July 1993.

  8. Sodium channels in the cytoplasm of Schwann cells

    SciTech Connect

    Ritchie, J.M. ); Black, J.A.; Waxman, S.G. Veterans Affairs Medical Center, West Haven, CT ); Angelides, K.J. )

    1990-12-01

    Immunoblotting, ultrastructural immunocytochemistry, and tritiated saxitoxin (({sup 3}H)STX) binding experiments were used to study sodium channel localization in Schwann cells. Polyclonal antibody 7493, which is directed against purifed sodium channels from rat brain, specifically recognized a 260-kDa protein corresponding to the {alpha} subunit of the sodium channel in immunoblots of crude glycoproteins from rat sciatic nerve. Electron microscopic localization of sodium channel immunoreactivity within adult rat sciatic nerves reveals heavy staining of the axon membrane at the node of Ranvier, in contrast to the internodal axon membrane, which does not stain. Schwann cells including perinodal processes also exhibit antibody 7493 immunoreactivity, localized within both the cytoplasm and the plasmalemma of the Schwann cell. To examine further the possibility that sodium channels are localized within Schwann cell cytoplasm, ({sup 3}H)STX binding was studied in cultured rabbit Schwann cells, both intact and after homogenization. Saturable binding of STX was singificantly higher in homogenized Schwann cells than in intact Schwann cells. Moreover, the equilibrium dissociation constant was higher for homogenized preparations (1.77 {plus minus} 0.37 nM) than for intact Schwann cells (1.06 {plus minus} 0.29 nM). These data suggest the presence of an intracellular pool of sodium channels or channel presursors in Schwann cells.

  9. Sodium channels in the cytoplasm of Schwann cells.

    PubMed Central

    Ritchie, J M; Black, J A; Waxman, S G; Angelides, K J

    1990-01-01

    Immunoblotting, ultrastructural immunocytochemistry, and tritiated saxitoxin ([3H]STX) binding experiments were used to study sodium channel localization in Schwann cells. Polyclonal antibody 7493, which is directed against purified sodium channels from rat brain, specifically recognizes a 260-kDa protein corresponding to the alpha subunit of the sodium channel in immunoblots of crude glycoproteins from rat sciatic nerve. Electron microscopic localization of sodium channel immunoreactivity within adult rat sciatic nerves reveals heavy staining of the axon membrane at the node of Ranvier, in contrast to the internodal axon membrane, which does not stain. Schwann cells including perinodal processes also exhibit antibody 7493 immunoreactivity, localized within both the cytoplasm and the plasmalemma of the Schwann cell. To examine further the possibility that sodium channels are localized within Schwann cell cytoplasm, [3H]STX binding was studied in cultured rabbit Schwann cells, both intact and after homogenization. Saturable binding of STX was significantly higher in homogenized Schwann cells (410 +/- 37 fmol/mg of protein) than in intact Schwann cells (214 +/- 21 fmol/mg of protein). Moreover, the equilibrium dissociation constant was higher for homogenized preparations (1.77 +/- 0.37 nM) than for intact Schwann cells (1.06 +/- 0.29 nM). These data suggest the presence of an intracellular pool of sodium channels or channel precursors in Schwann cells. Images PMID:2174558

  10. [Determination of furbenicillin sodium and its related substances by HPLC].

    PubMed

    Chang, Yan; Tian, Ye; Ma, Yue; Hu, Chang-qin

    2015-12-01

    Furbenicillin is a broad-spectrum semisynthetic penicillin with strong antibacterial activity against Gram-negative bacteria. Furbenicillin sodium is determined by volumetric method in current criteria. However, the criteria does not contain an assay of related substances of furbenicillin sodium. In this study, we established a method for detection and analysis of furbenicillin sodium and its related substances by HPLC. The analysis was performed with a C18 column under a gradient elution, the detection wavelength was 225 nm, and the column temperature was 35 degrees C. The reliability and accuracy of established method was validated in this study. Pure samples of furbenicillin sodium and its related substances were prepared. The structures, biological activities, and chromatographic retention behaviors of furbenicillin sodium and its related substances were identified using NMR, CLSI agar dilution method, and HPLC. All results in the current study provide ample evidence that this method is able to determine the reasonable limits in the quality-control protocol for furbenicillin sodium. PMID:27169288

  11. 21 CFR 184.1763 - Sodium hydroxide.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... empirical formula is NaOH. Sodium hydroxide is prepared commercially by the electrolysis of sodium chloride... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Sodium hydroxide. 184.1763 Section 184.1763 Food... Specific Substances Affirmed as GRAS § 184.1763 Sodium hydroxide. (a) Sodium hydroxide (NaOH, CAS Reg....

  12. 21 CFR 184.1763 - Sodium hydroxide.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... empirical formula is NaOH. Sodium hydroxide is prepared commercially by the electrolysis of sodium chloride... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Sodium hydroxide. 184.1763 Section 184.1763 Food... Specific Substances Affirmed as GRAS § 184.1763 Sodium hydroxide. (a) Sodium hydroxide (NaOH, CAS Reg....

  13. 21 CFR 184.1763 - Sodium hydroxide.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... empirical formula is NaOH. Sodium hydroxide is prepared commercially by the electrolysis of sodium chloride... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium hydroxide. 184.1763 Section 184.1763 Food... Specific Substances Affirmed as GRAS § 184.1763 Sodium hydroxide. (a) Sodium hydroxide (NaOH, CAS Reg....

  14. 21 CFR 184.1763 - Sodium hydroxide.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... empirical formula is NaOH. Sodium hydroxide is prepared commercially by the electrolysis of sodium chloride... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Sodium hydroxide. 184.1763 Section 184.1763 Food... Specific Substances Affirmed as GRAS § 184.1763 Sodium hydroxide. (a) Sodium hydroxide (NaOH, CAS Reg....

  15. 21 CFR 201.64 - Sodium labeling.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... contains sodium bicarbonate, sodium phosphate, or sodium biphosphate as an active ingredient for oral... 21 Food and Drugs 4 2013-04-01 2013-04-01 false Sodium labeling. 201.64 Section 201.64 Food and... LABELING Labeling Requirements for Over-the-Counter Drugs § 201.64 Sodium labeling. (a) The labeling...

  16. 21 CFR 184.1733 - Sodium benzoate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Specific Substances Affirmed as GRAS § 184.1733 Sodium benzoate. (a) Sodium benzoate is the chemical benzoate of soda (C7H5NaO2), produced by the neutralization of benzoic acid with sodium bicarbonate, sodium... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Sodium benzoate. 184.1733 Section 184.1733...

  17. 21 CFR 201.64 - Sodium labeling.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... contains sodium bicarbonate, sodium phosphate, or sodium biphosphate as an active ingredient for oral... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Sodium labeling. 201.64 Section 201.64 Food and... LABELING Labeling Requirements for Over-the-Counter Drugs § 201.64 Sodium labeling. (a) The labeling...

  18. 21 CFR 201.64 - Sodium labeling.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... contains sodium bicarbonate, sodium phosphate, or sodium biphosphate as an active ingredient for oral... 21 Food and Drugs 4 2012-04-01 2012-04-01 false Sodium labeling. 201.64 Section 201.64 Food and... LABELING Labeling Requirements for Over-the-Counter Drugs § 201.64 Sodium labeling. (a) The labeling...

  19. 21 CFR 184.1733 - Sodium benzoate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Substances Affirmed as GRAS § 184.1733 Sodium benzoate. (a) Sodium benzoate is the chemical benzoate of soda (C7H5NaO2), produced by the neutralization of benzoic acid with sodium bicarbonate, sodium carbonate, or... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium benzoate. 184.1733 Section 184.1733 Food...

  20. 21 CFR 184.1733 - Sodium benzoate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Specific Substances Affirmed as GRAS § 184.1733 Sodium benzoate. (a) Sodium benzoate is the chemical benzoate of soda (C7H5NaO2), produced by the neutralization of benzoic acid with sodium bicarbonate, sodium... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Sodium benzoate. 184.1733 Section 184.1733...

  1. 21 CFR 201.64 - Sodium labeling.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... contains sodium bicarbonate, sodium phosphate, or sodium biphosphate as an active ingredient for oral... 21 Food and Drugs 4 2014-04-01 2014-04-01 false Sodium labeling. 201.64 Section 201.64 Food and... LABELING Labeling Requirements for Over-the-Counter Drugs § 201.64 Sodium labeling. (a) The labeling...

  2. 21 CFR 186.1756 - Sodium formate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sodium formate. 186.1756 Section 186.1756 Food and....1756 Sodium formate. (a) Sodium formate (CHNaO2, CAS Reg. No. 141-53-7) is the sodium salt of formic acid. It is produced by the reaction of carbon monoxide with sodium hydroxide. (b) The ingredient...

  3. 21 CFR 184.1724 - Sodium alginate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium alginate. 184.1724 Section 184.1724 Food and... Substances Affirmed as GRAS § 184.1724 Sodium alginate. (a) Sodium alginate (CAS Reg. No. 9005-38-3) is the sodium salt of alginic acid, a natural polyuronide constituent of certain brown algae. Sodium alginate...

  4. 21 CFR 184.1724 - Sodium alginate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sodium alginate. 184.1724 Section 184.1724 Food... GRAS § 184.1724 Sodium alginate. (a) Sodium alginate (CAS Reg. No. 9005-38-3) is the sodium salt of alginic acid, a natural polyuronide constituent of certain brown algae. Sodium alginate is prepared by...

  5. Action of insecticidal N-alkylamides at site 2 of the voltage-sensitive sodium channel

    SciTech Connect

    Ottea, J.A.; Payne, G.T.; Soderlund, D.M. )

    1990-08-01

    Nine synthetic N-alkylamides were examined as inhibitors of the specific binding of ({sup 3}H)batrachotoxinin A 20{alpha}-benzoate (({sup 3}H)BTX-B) to sodium channels and as activators of sodium uptake in mouse brain synaptoneurosomes. In the presence of scorpion (Leiurus quinquestriatus) venom, the six insecticidal analogues were active as both inhibitors of ({sup 3}H)BTX-B binding and stimulators of sodium uptake. These findings are consistent with an action of these compounds at the alkaloid activator recognition site (site 2) of the voltage-sensitive sodium channel. The three noninsecticidal N-alkylamides also inhibited ({sup 3}H)BTX-B binding but were ineffective as activators of sodium uptake. Concentration-response studies revealed that some of the insecticidal amides also enhanced sodium uptake through a second, high-affinity interaction that does not involve site 2, but this secondary effect does not appear to be correlated with insecticidal activity. The activities of N-alkylamides as sodium channel activators were influenced by the length of the alkenyl chain and the location of unsaturation within the molecule. These results further define the actions of N-alkylamides on sodium channels and illustrate the significance of the multiple binding domains of the sodium channel as target sites for insect control agents.

  6. Robust and intelligent bearing estimation

    SciTech Connect

    Claassen, J.P.

    1998-07-01

    As the monitoring thresholds of global and regional networks are lowered, bearing estimates become more important to the processes which associate (sparse) detections and which locate events. Current methods of estimating bearings from observations by 3-component stations and arrays lack both accuracy and precision. Methods are required which will develop all the precision inherently available in the arrival, determine the measurability of the arrival, provide better estimates of the bias induced by the medium, permit estimates at lower SNRs, and provide physical insight into the effects of the medium on the estimates. Initial efforts have focused on 3-component stations since the precision is poorest there. An intelligent estimation process for 3-component stations has been developed and explored. The method, called SEE for Search, Estimate, and Evaluation, adaptively exploits all the inherent information in the arrival at every step of the process to achieve optimal results. In particular, the approach uses a consistent and robust mathematical framework to define the optimal time-frequency windows on which to make estimates, to make the bearing estimates themselves, and to withdraw metrics helpful in choosing the best estimate(s) or admitting that the bearing is immeasurable. The approach is conceptually superior to current methods, particular those which rely on real values signals. The method has been evaluated to a considerable extent in a seismically active region and has demonstrated remarkable utility by providing not only the best estimates possible but also insight into the physical processes affecting the estimates. It has been shown, for example, that the best frequency at which to make an estimate seldom corresponds to the frequency having the best detection SNR and sometimes the best time interval is not at the onset of the signal. The method is capable of measuring bearing dispersion, thereby withdrawing the bearing bias as a function of frequency

  7. Himalayan black bear mauling: offense or defense?

    PubMed

    Thakur, Jagdeep Singh; Mohan, Chander; Sharma, Dev R

    2007-01-01

    The Asiatic Black Bear (Ursus thibetanus or Selenarctos thibetanus), also known as the Tibetan black bear, the Himalayan black bear, or the moon bear is a omnivorous mammal. This animal is declared threatened animal and rarely comes in human contact. Recent decrease in forest area has, however, increased the chances of bear-human interaction, hence causing injuries to humans. There is only one published report in English literature on Himalayan black bear mauling. We present 5 cases referred to our department over a period of 1 year. PMID:17606040

  8. TOOL ASSEMBLY WITH BI-DIRECTIONAL BEARING

    DOEpatents

    Longhurst, G.E.

    1961-07-11

    A two-direction motion bearing which is incorporated in a refueling nuclear fuel element trsnsfer tool assembly is described. A plurality of bi- directional bearing assembliesare fixed equi-distantly about the circumference of the transfer tool assembly to provide the tool assembly with a bearing surface- for both axial and rotational motion. Each bi-directional bearing assembly contains a plurality of circumferentially bulged rollers mounted in a unique arrangement which will provide a bearing surface for rotational movement of the tool assembly within a bore. The bi-direc tional bearing assembly itself is capable of rational motion and thus provides for longitudinal movement of the tool assembly.

  9. Advanced Active-Magnetic-Bearing Thrust-Measurement System

    NASA Technical Reports Server (NTRS)

    Imlach, Joseph; Kasarda, Mary; Blumber, Eric

    2008-01-01

    An advanced thrust-measurement system utilizes active magnetic bearings to both (1) levitate a floating frame in all six degrees of freedom and (2) measure the levitation forces between the floating frame and a grounded frame. This system was developed for original use in measuring the thrust exerted by a rocket engine mounted on the floating frame, but can just as well be used in other force-measurement applications. This system offers several advantages over prior thrust-measurement systems based on mechanical support by flexures and/or load cells: The system includes multiple active magnetic bearings for each degree of freedom, so that by selective use of one, some, or all of these bearings, it is possible to test a given article over a wide force range in the same fixture, eliminating the need to transfer the article to different test fixtures to obtain the benefit of full-scale accuracy of different force-measurement devices for different force ranges. Like other active magnetic bearings, the active magnetic bearings of this system include closed-loop control subsystems, through which the stiffness and damping characteristics of the magnetic bearings can be modified electronically. The design of the system minimizes or eliminates cross-axis force-measurement errors. The active magnetic bearings are configured to provide support against movement along all three orthogonal Cartesian axes, and such that the support along a given axis does not produce force along any other axis. Moreover, by eliminating the need for such mechanical connections as flexures used in prior thrust-measurement systems, magnetic levitation of the floating frame eliminates what would otherwise be major sources of cross-axis forces and the associated measurement errors. Overall, relative to prior mechanical-support thrust-measurement systems, this system offers greater versatility for adaptation to a variety of test conditions and requirements. The basic idea of most prior active-magnetic-bearing

  10. No sodium in the vapour plumes of Enceladus.

    PubMed

    Schneider, Nicholas M; Burger, Matthew H; Schaller, Emily L; Brown, Michael E; Johnson, Robert E; Kargel, Jeffrey S; Dougherty, Michele K; Achilleos, Nicholas A

    2009-06-25

    The discovery of water vapour and ice particles erupting from Saturn's moon Enceladus fuelled speculation that an internal ocean was the source. Alternatively, the source might be ice warmed, melted or crushed by tectonic motions. Sodium chloride (that is, salt) is expected to be present in a long-lived ocean in contact with a rocky core. Here we report a ground-based spectroscopic search for atomic sodium near Enceladus that places an upper limit on the mixing ratio in the vapour plumes orders of magnitude below the expected ocean salinity. The low sodium content of escaping vapour, together with the small fraction of salt-bearing particles, argues against a situation in which a near-surface geyser is fuelled by a salty ocean through cracks in the crust. The lack of observable sodium in the vapour is consistent with a wide variety of alternative eruption sources, including a deep ocean, a freshwater reservoir, or ice. The existing data may be insufficient to distinguish between these hypotheses. PMID:19553993

  11. Sodium heat transfer system modeling

    NASA Astrophysics Data System (ADS)

    Baker, A. F.; Fewell, M. E.

    1983-11-01

    The sodium heat transfer system of the international energy agency (IEA) small solar power systems (SSPS) central receiver system (CRS), which includes the heliostat field, receiver, hot and cold storage vessels, and sodium/water steam generator was modeled. The computer code SOLTES (simulator of large thermal energy systems), was used to model this system. The results from SOLTES are compared to measured data.

  12. ID-69 Sodium drain experiments

    SciTech Connect

    Johnston, D.C.

    1996-09-19

    This paper describes experiments to determine the sodium retention and drainage from the two key areas of an ID-69. This information is then used as the initiation point for guidelines of how to proceed with washing an ID-69 in the IEM Cell Sodium Removal System.

  13. A time delay controller for magnetic bearings

    NASA Technical Reports Server (NTRS)

    Youcef-Toumi, K.; Reddy, S.

    1991-01-01

    The control of systems with unknown dynamics and unpredictable disturbances has raised some challenging problems. This is particularly important when high system performance needs to be guaranteed at all times. Recently, the Time Delay Control has been suggested as an alternative control scheme. The proposed control system does not require an explicit plant model nor does it depend on the estimation of specific plant parameters. Rather, it combines adaptation with past observations to directly estimate the effect of the plant dynamics. A control law is formulated for a class of dynamic systems and a sufficient condition is presented for control systems stability. The derivation is based on the bounded input-bounded output stability approach using L sub infinity function norms. The control scheme is implemented on a five degrees of freedom high speed and high precision magnetic bearing. The control performance is evaluated using step responses, frequency responses, and disturbance rejection properties. The experimental data show an excellent control performance despite the system complexity.

  14. Hybrid bearings for turbopumps and the like

    NASA Technical Reports Server (NTRS)

    Justak, John F. (Inventor); Owens, Gregg R. (Inventor)

    1994-01-01

    In rocket engines power is usually obtained by burning fuel and oxidizer which are mixed, pressurized, and directed to a combustion chamber by means of turbopumps. Roller bearings are generally used in these turbopumps, but because of bearing demands hydrostatic bearings were proposed. The use of such bearings is quite feasible because during flight hydrostatic lubrication can reduce roller bearing wear. A disadvantage of such proposals is that during startup, acceleration, and shutdown high pressure fluids are not available for hydrostatic bearings. The fluid lubrication film is not always present in bearings of turbopumps. During these periods a second bearing is required to carry the load. This requirement suggests the use of hybrid bearings in rocket engine turbopumps. Such duplex bearings were provided, but when their inner races are keyed to the shaft or journal two of them are required. And such duplex bearings do not wear evenly. A hybrid hydrostatic-rolling element bearing was provided wherein the rolling element bearing is locked on the stationary housing rather than on the rotating journal.

  15. Journal and Wave Bearing Impedance Calculation Software

    NASA Technical Reports Server (NTRS)

    Hanford, Amanda; Campbell, Robert

    2012-01-01

    The wave bearing software suite is a MALTA application that computes bearing properties for user-specified wave bearing conditions, as well as plain journal bearings. Wave bearings are fluid film journal bearings with multi-lobed wave patterns around the circumference of the bearing surface. In this software suite, the dynamic coefficients are outputted in a way for easy implementation in a finite element model used in rotor dynamics analysis. The software has a graphical user interface (GUI) for inputting bearing geometry parameters, and uses MATLAB s structure interface for ease of interpreting data. This innovation was developed to provide the stiffness and damping components of wave bearing impedances. The computational method for computing bearing coefficients was originally designed for plain journal bearings and tilting pad bearings. Modifications to include a wave bearing profile consisted of changing the film thickness profile given by an equation, and writing an algorithm to locate the integration limits for each fluid region. Careful consideration was needed to implement the correct integration limits while computing the dynamic coefficients, depending on the form of the input/output variables specified in the algorithm.

  16. Short-bearing approximation for full journal bearings

    NASA Technical Reports Server (NTRS)

    Ocvirk, F W

    1952-01-01

    A short-bearing approximation of pressure distribution in the oil film is presented which is an extension of the pressure-distribution function of Michell and Cardullo and includes end-leakage effects. Equations giving applied load, attitude angle, location and magnitude of peak film pressure, friction, and required oil flow rate as functions of the eccentricity ratio are also given. The capacity number, a basic non dimensional quantity resulting from this analysis is the product of the Sommerfeld number and the square of the length-diameter ratio. Curves determined by this analysis are compared with previously published experimental data and theoretical curves of Sommerfeld and Cameron and Wood. Conclusions reached indicate that this approximation is of practical value for analysis of short bearings.

  17. Mobile bearing and fixed bearing total knee arthroplasty

    PubMed Central

    Dolfin, Marco; Saccia, Francesco

    2016-01-01

    The mobile bearing (MB) concept in total knee arthroplasty (TKA) was developed as an alternative to fixed bearing (FB) implants in order to reduce wear and improve range of motion (ROM), especially focused on younger patients. Unfortunately, its theoretical advantages are still controversial. In this paper we exhibit a review of the more recent literature available comparing FB and MB designs in biomechanical and clinical aspects, including observational studies, clinical trials, national and international registries analyses, randomized controlled trials, meta-analyses and Cochrane reviews. Except for some minor aspects, none of the studies published so far has reported a significant improvement related to MBs regarding patient satisfaction, clinical, functional and radiological outcome or medium and long-term survivorship. Thus the presumed superiority of MBs over FBs appears largely inconsistent. The routine use of MB is not currently supported by adequate evidences; implant choice should be therefore made on the basis of other factors, including cost and surgeon experience. PMID:27162777

  18. Evolutionary primacy of sodium bioenergetics

    PubMed Central

    Mulkidjanian, Armen Y; Galperin, Michael Y; Makarova, Kira S; Wolf, Yuri I; Koonin, Eugene V

    2008-01-01

    Background The F- and V-type ATPases are rotary molecular machines that couple translocation of protons or sodium ions across the membrane to the synthesis or hydrolysis of ATP. Both the F-type (found in most bacteria and eukaryotic mitochondria and chloroplasts) and V-type (found in archaea, some bacteria, and eukaryotic vacuoles) ATPases can translocate either protons or sodium ions. The prevalent proton-dependent ATPases are generally viewed as the primary form of the enzyme whereas the sodium-translocating ATPases of some prokaryotes are usually construed as an exotic adaptation to survival in extreme environments. Results We combine structural and phylogenetic analyses to clarify the evolutionary relation between the proton- and sodium-translocating ATPases. A comparison of the structures of the membrane-embedded oligomeric proteolipid rings of sodium-dependent F- and V-ATPases reveals nearly identical sets of amino acids involved in sodium binding. We show that the sodium-dependent ATPases are scattered among proton-dependent ATPases in both the F- and the V-branches of the phylogenetic tree. Conclusion Barring convergent emergence of the same set of ligands in several lineages, these findings indicate that the use of sodium gradient for ATP synthesis is the ancestral modality of membrane bioenergetics. Thus, a primitive, sodium-impermeable but proton-permeable cell membrane that harboured a set of sodium-transporting enzymes appears to have been the evolutionary predecessor of the more structurally demanding proton-tight membranes. The use of proton as the coupling ion appears to be a later innovation that emerged on several independent occasions. Reviewers This article was reviewed by J. Peter Gogarten, Martijn A. Huynen, and Igor B. Zhulin. For the full reviews, please go to the Reviewers' comments section. PMID:18380897

  19. 40 CFR 415.170 - Applicability; description of the sodium dichromate and sodium sulfate production subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... sodium dichromate and sodium sulfate production subcategory. 415.170 Section 415.170 Protection of... MANUFACTURING POINT SOURCE CATEGORY Sodium Dichromate and Sodium Sulfate Production Subcategory § 415.170 Applicability; description of the sodium dichromate and sodium sulfate production subcategory. The provisions...

  20. Improved transducer for squeeze-film bearings

    NASA Technical Reports Server (NTRS)

    Hoogenbloom, L.

    1971-01-01

    Transducer amplifies vibrations produced by piezoelectric drivers, creating greater amplitudes than were possible with direct drive devices. Drivers isolated from bearing surfaces result in bearings with high axial load capacity and stiffness, thus, wear on ceramic cylinders is reduced.

  1. Rolling Element Bearing Stiffness Matrix Determination (Presentation)

    SciTech Connect

    Guo, Y.; Parker, R.

    2014-01-01

    Current theoretical bearing models differ in their stiffness estimates because of different model assumptions. In this study, a finite element/contact mechanics model is developed for rolling element bearings with the focus of obtaining accurate bearing stiffness for a wide range of bearing types and parameters. A combined surface integral and finite element method is used to solve for the contact mechanics between the rolling elements and races. This model captures the time-dependent characteristics of the bearing contact due to the orbital motion of the rolling elements. A numerical method is developed to determine the full bearing stiffness matrix corresponding to two radial, one axial, and two angular coordinates; the rotation about the shaft axis is free by design. This proposed stiffness determination method is validated against experiments in the literature and compared to existing analytical models and widely used advanced computational methods. The fully-populated stiffness matrix demonstrates the coupling between bearing radial, axial, and tilting bearing deflections.

  2. A Preliminary Foil Gas Bearing Performance Map

    NASA Technical Reports Server (NTRS)

    DellaCorte, Christopher; Radil, Kevin C.; Bruckner, Robert J.; Howard, S. Adam

    2006-01-01

    Recent breakthrough improvements in foil gas bearing load capacity, high temperature tribological coatings and computer based modeling have enabled the development of increasingly larger and more advanced Oil-Free Turbomachinery systems. Successful integration of foil gas bearings into turbomachinery requires a step wise approach that includes conceptual design and feasibility studies, bearing testing, and rotor testing prior to full scale system level demonstrations. Unfortunately, the current level of understanding of foil gas bearings and especially their tribological behavior is often insufficient to avoid developmental problems thereby hampering commercialization of new applications. In this paper, a new approach loosely based upon accepted hydrodynamic theory, is developed which results in a "Foil Gas Bearing Performance Map" to guide the integration process. This performance map, which resembles a Stribeck curve for bearing friction, is useful in describing bearing operating regimes, performance safety margins, the effects of load on performance and limiting factors for foil gas bearings.

  3. Happy Birthday Smokey Bear from Joe Acaba

    NASA Video Gallery

    Expedition 32 Flight Engineer Joe Acaba wishes Smokey Bear a Happy Birthday. For 68 years Smokey Bear has been promoting fire safety and prevention through the message, “Only You Can Prevent Wild...

  4. Sodium fire testing: structural evaluation of sodium fire suppression system

    SciTech Connect

    1984-08-01

    This report describes the development and the lessons learned from the Clinch River Breeder Reactor Sodium Fire Testing Program (DRS 26.03). The purpose of this program was to evaluate the behavior of the Sodium Fire Suppression System and validate the analytical techniques used in the calculation of the effects of sodium fires in air-filled cells. This report focuses on the fire suppression capability and the structural integrity of the Fire Suppression System. System features are discussed; the test facility is described and the key results are provided. Modifications to the fire suppression system and the plant made as a result of test experience are also discussed.

  5. Stable isotopes to detect food-conditioned bears and to evaluate human-bear management

    USGS Publications Warehouse

    Hopkins, John B., III; Koch, Paul L.; Schwartz, Charles C.; Ferguson, Jake M.; Greenleaf, Schuyler S.; Kalinowski, Steven T.

    2012-01-01

    We used genetic and stable isotope analysis of hair from free-ranging black bears (Ursus americanus) in Yosemite National Park, California, USA to: 1) identify bears that consume human food, 2) estimate the diets of these bears, and 3) evaluate the Yosemite human–bear management program. Specifically, we analyzed the isotopic composition of hair from bears known a priori to be food-conditioned or non-food-conditioned and used these data to predict whether bears with an unknown management status were food-conditioned (FC) or non-food-conditioned (NFC). We used a stable isotope mixing model to estimate the proportional contribution of natural foods (plants and animals) versus human food in the diets of FC bears. We then used results from both analyses to evaluate proactive (population-level) and reactive (individual-level) human–bear management, and discussed new metrics to evaluate the overall human–bear management program in Yosemite. Our results indicated that 19 out of 145 (13%) unknown bears sampled from 2005 to 2007 were food-conditioned. The proportion of human food in the diets of known FC bears likely declined from 2001–2003 to 2005–2007, suggesting proactive management was successful in reducing the amount of human food available to bears. In contrast, reactive management was not successful in changing the management status of known FC bears to NFC bears, or in reducing the contribution of human food to the diets of FC bears. Nine known FC bears were recaptured on 14 occasions from 2001 to 2007; all bears were classified as FC during subsequent recaptures, and human–bear management did not reduce the amount of human food in the diets of FC bears. Based on our results, we suggest Yosemite continue implementing proactive human–bear management, reevaluate reactive management, and consider removing problem bears (those involved in repeated bear incidents) from the population.

  6. Tables of thermodynamic properties of sodium

    SciTech Connect

    Fink, J.K.

    1982-06-01

    The thermodynamic properties of saturated sodium, superheated sodium, and subcooled sodium are tabulated as a function of temperature. The temperature ranges are 380 to 2508 K for saturated sodium, 500 to 2500 K for subcooled sodium, and 400 to 1600 K for superheated sodium. Tabulated thermodynamic properties are enthalpy, heat capacity, pressure, entropy, density, instantaneous thermal expansion coefficient, compressibility, and thermal pressure coefficient. Tables are given in SI units and cgs units.

  7. 21 CFR 186.1770 - Sodium oleate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sodium oleate. 186.1770 Section 186.1770 Food and....1770 Sodium oleate. (a) Sodium oleate (C18H33O2Na, CAS Reg. No. 143-19-1) is the sodium salt of oleic.... Commercially, sodium oleate is made by mixing and heating flaked sodium hydroxide and oleic acid. (b)...

  8. Mercury in polar bears from Alaska

    SciTech Connect

    Lentfer, J.W.; Galster, W.A.

    1987-04-01

    Alaskan polar bear (Ursus maritimus) muscle and liver samples collected in 1972 were analyzed for total mercury. Bears north of Alaska had more mercury than bears west of Alaska. The only difference between young and adult animals was in the northern area where adults had more mercury in liver tissue than young animals. Levels were probably not high enough to be a serious threat to bears.

  9. Research In Diagnosing Bearing Defects From Vibrations

    NASA Technical Reports Server (NTRS)

    Zoladz, T.; Earhart, E.; Fiorucci, T.

    1995-01-01

    Report describes research in bearing-defect signature analysis - use of vibration-signal analysis to diagnose defects in roller and ball bearings. Experiments performed on bearings in good condition and other bearings in which various parts scratched to provide known defects correlated with vibration signals. Experiments performed on highly instrumented motor-driven rotor assembly at speeds up to 10,050 r/min, using accelerometers, velocity probes, and proximity sensors mounted at various locations on assembly to measure vibrations.

  10. Human impacts on bear habitat use

    USGS Publications Warehouse

    Mattson, David J.

    1990-01-01

    : Human effects on bear habitat use are mediated through food biomass changes, bear tolerance of humans and their impacts, and human tolerance of bears. Large-scale changes in bear food biomass have been caused by conversion of wildlands and waterways to intensive human use, and by the introduction of exotic pathogens. Bears consume virtually all human foods that have been established in former wildlands, but bear use has been limited by access. Air pollution has also affected bear food biomass on a small scale and is likely to have major future impacts on bear habitat through climatic warming. Major changes in disturbance cycles and landscape mosaics wrought by humans have further altered temporal and spatial pulses of bear food production. These changes have brought short-term benefits in places, but have also added long-term stresses to most bear populations. Although bears tend to avoid humans, they will also use exotic and native foods in close proximity to humans. Subadult males and adult females are more often impelled to forage closer to humans because of their energetic predicament and because more secure sites are often preempted by adult males. Although male bears are typically responsible for most livestock predation, adult females and subadult males are more likely to be habituated to humans because they tend to forage closer to humans. Elimination of human-habituated bears predictably reduces effective carrying capacity and is more likely to be a factor in preserving bear populations where humans are present in moderate-to-high densities. If humans desire to preserve viable bear populations, they will either have to accept increased risk of injury associated with preserving habituated animals, or continue to crop habituated bears while at the same time preserving large tracts of wildlands free from significant human intrusion.

  11. Thin film superconductor magnetic bearings

    DOEpatents

    Weinberger, Bernard R.

    1995-12-26

    A superconductor magnetic bearing includes a shaft (10) that is subject to a load (L) and rotatable around an axis of rotation, a magnet (12) mounted to the shaft, and a stator (14) in proximity to the shaft. The stator (14) has a superconductor thin film assembly (16) positioned to interact with the magnet (12) to produce a levitation force on the shaft (10) that supports the load (L). The thin film assembly (16) includes at least two superconductor thin films (18) and at least one substrate (20). Each thin film (18) is positioned on a substrate (20) and all the thin films are positioned such that an applied magnetic field from the magnet (12) passes through all the thin films. A similar bearing in which the thin film assembly (16) is mounted on the shaft (10) and the magnet (12) is part of the stator (14) also can be constructed.

  12. Dynamics of air bearing sliders

    NASA Astrophysics Data System (ADS)

    Witelski, T. P.

    1998-03-01

    In this paper we present new results for the dynamics of a problem for the interaction of a compressible gas flow with a movable rigid surface. Compressible lubrication theory is applied to describe the dynamics of the vertical motion of air bearing sliders used in computer hard disk drives. In the limit of large bearing number we show this problem can be reduced to a nonlinear integrodifferential equation. Linear stability analysis and perturbation methods show that over the range of possible slider positions there is an infinite sequence of Hopf bifurcations yielding stable large amplitude periodic orbits. The dynamics of near-crash behavior and interaction with a moving disk surface are also addressed.

  13. Thin film superconductor magnetic bearings

    SciTech Connect

    Weinberger, B.R.

    1995-12-26

    A superconductor magnetic bearing includes a shaft that is subject to a load (L) and rotatable around an axis of rotation, a magnet mounted to the shaft, and a stator in proximity to the shaft. The stator has a superconductor thin film assembly positioned to interact with the magnet to produce a levitation force on the shaft that supports the load (L). The thin film assembly includes at least two superconductor thin films and at least one substrate. Each thin film is positioned on a substrate and all the thin films are positioned such that an applied magnetic field from the magnet passes through all the thin films. A similar bearing in which the thin film assembly is mounted on the shaft and the magnet is part of the stator also can be constructed. 8 figs.

  14. Air Bearing Lift Pad (ABLP)

    NASA Technical Reports Server (NTRS)

    Dane, Dan H.; Blaise, Herman T.

    1968-01-01

    Typical air bearings float on air films of only a few thousandths of an inch and so will only operate above very smooth, even surfaces. For the mechanical simulation of space, the small drag of the bladder type air pads is much more than can be coped with, and the practicality of large floor areas being machined for precision air bearings is nonexistent. To enable operation above surfaces that undulate slightly or feature cracks and discontinuities, an ABLP has been developed. It consists of a rigid pad beneath which an inflatable bladder is mounted. The bladder is inflated with air which then escapes through passages into a cavity in the center of the bladder to produce the lifting energy. As the air escapes about the perimeter of the bladder, a certain degree of balance and equilibrium is imparted to the pad as it is able to move a limited weight across slightly uneven surfaces.

  15. Susceptibility of Clostridium difficile to the food preservatives sodium nitrite, sodium nitrate and sodium metabisulphite.

    PubMed

    Lim, Su-Chen; Foster, Niki F; Riley, Thomas V

    2016-02-01

    Clostridium difficile is an important enteric pathogen of humans and food animals. Recently it has been isolated from retail foods with prevalences up to 42%, prompting concern that contaminated foods may be one of the reasons for increased community-acquired C. difficile infection (CA-CDI). A number of studies have examined the prevalence of C. difficile in raw meats and fresh vegetables; however, fewer studies have examined the prevalence of C. difficile in ready-to-eat meat. The aim of this study was to investigate the in vitro susceptibility of 11 C. difficile isolates of food animal and retail food origins to food preservatives commonly used in ready-to-eat meats. The broth microdilution method was used to determine the minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) for sodium nitrite, sodium nitrate and sodium metabisulphite against C. difficile. Checkerboard assays were used to investigate the combined effect of sodium nitrite and sodium nitrate, commonly used in combination in meats. Modal MIC values for sodium nitrite, sodium nitrate and sodium metabisulphite were 250 μg/ml, >4000 μg/ml and 1000 μg/ml, respectively. No bactericidal activity was observed for all three food preservatives. The checkerboard assays showed indifferent interaction between sodium nitrite and sodium nitrate. This study demonstrated that C. difficile can survive in the presence of food preservatives at concentrations higher than the current maximum permitted levels allowed in ready-to-eat meats. The possibility of retail ready-to-eat meats contaminated with C. difficile acting as a source of CDI needs to be investigated. PMID:26700884

  16. Foil bearing lubrication theory including compressibility effects

    NASA Technical Reports Server (NTRS)

    Gorla, Rama Subba Reddy; Catalano, Daniel A.

    1987-01-01

    An analysis is presented to determine the film thickness in a foil bearing. Using the Reynolds equation and including the compressibility effects of the gas, an equation was developed applicable to the film thickness in a foil bearing. The bearing was divided into three regions, namely, the entrance region, middle region and exit region. Solutions are obtained for the film thickness in each region.

  17. Passive Thermal Management of Foil Bearings

    NASA Technical Reports Server (NTRS)

    Bruckner, Robert J. (Inventor)

    2015-01-01

    Systems and methods for passive thermal management of foil bearing systems are disclosed herein. The flow of the hydrodynamic film across the surface of bearing compliant foils may be disrupted to provide passive cooling and to improve the performance and reliability of the foil bearing system.

  18. 49 CFR 229.64 - Plain bearings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Plain bearings. 229.64 Section 229.64 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION....64 Plain bearings. A plain bearing box shall contain visible free oil and may not be cracked to...

  19. 49 CFR 229.64 - Plain bearings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Plain bearings. 229.64 Section 229.64 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION....64 Plain bearings. A plain bearing box shall contain visible free oil and may not be cracked to...

  20. 14 CFR 25.623 - Bearing factors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Bearing factors. 25.623 Section 25.623... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General § 25.623 Bearing factors. (a) Except... subject to pounding or vibration, must have a bearing factor large enough to provide for the effects...

  1. 14 CFR 25.623 - Bearing factors.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Bearing factors. 25.623 Section 25.623... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General § 25.623 Bearing factors. (a) Except... subject to pounding or vibration, must have a bearing factor large enough to provide for the effects...

  2. 14 CFR 29.623 - Bearing factors.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Bearing factors. 29.623 Section 29.623... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.623 Bearing factors. (a... subject to pounding or vibration, must have a bearing factor large enough to provide for the effects...

  3. 14 CFR 29.623 - Bearing factors.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Bearing factors. 29.623 Section 29.623... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.623 Bearing factors. (a... subject to pounding or vibration, must have a bearing factor large enough to provide for the effects...

  4. 14 CFR 27.623 - Bearing factors.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Bearing factors. 27.623 Section 27.623... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction General § 27.623 Bearing factors. (a) Except... subject to pounding or vibration, must have a bearing factor large enough to provide for the effects...

  5. 49 CFR 229.64 - Plain bearings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Plain bearings. 229.64 Section 229.64 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION....64 Plain bearings. A plain bearing box shall contain visible free oil and may not be cracked to...

  6. 14 CFR 27.623 - Bearing factors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Bearing factors. 27.623 Section 27.623... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction General § 27.623 Bearing factors. (a) Except... subject to pounding or vibration, must have a bearing factor large enough to provide for the effects...

  7. 14 CFR 29.623 - Bearing factors.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Bearing factors. 29.623 Section 29.623... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.623 Bearing factors. (a... subject to pounding or vibration, must have a bearing factor large enough to provide for the effects...

  8. 14 CFR 29.623 - Bearing factors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Bearing factors. 29.623 Section 29.623... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.623 Bearing factors. (a... subject to pounding or vibration, must have a bearing factor large enough to provide for the effects...

  9. 14 CFR 23.623 - Bearing factors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Bearing factors. 23.623 Section 23.623... Bearing factors. (a) Each part that has clearance (free fit), and that is subject to pounding or vibration, must have a bearing factor large enough to provide for the effects of normal relative motion. (b)...

  10. 14 CFR 29.623 - Bearing factors.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Bearing factors. 29.623 Section 29.623... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.623 Bearing factors. (a... subject to pounding or vibration, must have a bearing factor large enough to provide for the effects...

  11. 14 CFR 25.623 - Bearing factors.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Bearing factors. 25.623 Section 25.623... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General § 25.623 Bearing factors. (a) Except... subject to pounding or vibration, must have a bearing factor large enough to provide for the effects...

  12. 14 CFR 23.623 - Bearing factors.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Bearing factors. 23.623 Section 23.623... Bearing factors. (a) Each part that has clearance (free fit), and that is subject to pounding or vibration, must have a bearing factor large enough to provide for the effects of normal relative motion. (b)...

  13. 14 CFR 27.623 - Bearing factors.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Bearing factors. 27.623 Section 27.623... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction General § 27.623 Bearing factors. (a) Except... subject to pounding or vibration, must have a bearing factor large enough to provide for the effects...

  14. 14 CFR 23.623 - Bearing factors.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Bearing factors. 23.623 Section 23.623... Bearing factors. (a) Each part that has clearance (free fit), and that is subject to pounding or vibration, must have a bearing factor large enough to provide for the effects of normal relative motion. (b)...

  15. 49 CFR 229.64 - Plain bearings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Plain bearings. 229.64 Section 229.64 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION....64 Plain bearings. A plain bearing box shall contain visible free oil and may not be cracked to...

  16. 14 CFR 27.623 - Bearing factors.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Bearing factors. 27.623 Section 27.623... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction General § 27.623 Bearing factors. (a) Except... subject to pounding or vibration, must have a bearing factor large enough to provide for the effects...

  17. 14 CFR 23.623 - Bearing factors.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Bearing factors. 23.623 Section 23.623... Bearing factors. (a) Each part that has clearance (free fit), and that is subject to pounding or vibration, must have a bearing factor large enough to provide for the effects of normal relative motion. (b)...

  18. 14 CFR 25.623 - Bearing factors.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Bearing factors. 25.623 Section 25.623... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General § 25.623 Bearing factors. (a) Except... subject to pounding or vibration, must have a bearing factor large enough to provide for the effects...

  19. 14 CFR 25.623 - Bearing factors.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Bearing factors. 25.623 Section 25.623... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General § 25.623 Bearing factors. (a) Except... subject to pounding or vibration, must have a bearing factor large enough to provide for the effects...

  20. 14 CFR 27.623 - Bearing factors.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Bearing factors. 27.623 Section 27.623... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction General § 27.623 Bearing factors. (a) Except... subject to pounding or vibration, must have a bearing factor large enough to provide for the effects...

  1. 14 CFR 23.623 - Bearing factors.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Bearing factors. 23.623 Section 23.623... Bearing factors. (a) Each part that has clearance (free fit), and that is subject to pounding or vibration, must have a bearing factor large enough to provide for the effects of normal relative motion. (b)...

  2. 49 CFR 229.64 - Plain bearings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Plain bearings. 229.64 Section 229.64 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION....64 Plain bearings. A plain bearing box shall contain visible free oil and may not be cracked to...

  3. Steels For Rolling-Element Bearings

    NASA Technical Reports Server (NTRS)

    Zaretsky, Erwin V.

    1988-01-01

    Bearing lives increased by attention to details of processing and applications. NASA technical memorandum discusses selection of steels for long-life rolling-element bearings. After brief review of advances in manufacturing, report discusses effect of cleanliness of bearing material on fatigue in rolling element. Also discusses fracture toughnesses of through-hardened and case-hardened materials.

  4. Cryptosporidiosis in a black bear in Virginia.

    PubMed

    Duncan, R B; Caudell, D; Lindsay, D S; Moll, H D

    1999-04-01

    Cryptosporidiosis has not been previously reported in black bears in North America, either free-roaming or captive. However, oocysts have been documented in two captive Malayan sun bears (Helarctos malayanus) located in zoological parks in Taiwan. Developmental stages of Cryptosporidium parvum were observed in tissue sections from the small intestine of a black bear cub found dead in Virginia (USA). PMID:10231767

  5. Cool Polar Bears: Dabbing on the Texture

    ERIC Educational Resources Information Center

    O'Connell, Jean

    2011-01-01

    In this article, the author describes how her second-graders created their cool polar bears. The students used the elements of shape and texture to create the bears. They used Monet's technique of dabbing paint so as to give the bear some texture on his fur.

  6. Magnetic bearings for vibration control

    NASA Technical Reports Server (NTRS)

    Schweitzer, G.

    1985-01-01

    A survey is presented on the research of the Institute of Mechanics of the ETH in the field of vibration control with magnetic bearings. It shows a method for modelling an elastic rotor so that it can be represented by a low order model amenable to control techniques. It deals with the control law and spill-over effects, and it also discusses experimental results for an active resonance damper.

  7. Rolling element bearings in space

    NASA Technical Reports Server (NTRS)

    Kannel, J. W.; Dufrane, K. F.

    1986-01-01

    Some of the advances in tribology that have been associated with aerospace mechanisms are discussed. The needs of aerospace have been the dominant forces leading to improvements in understanding and applying tribology technology. In the past two decades improvements in understanding bearing torque, elastohydrodynamic lubrication, lubricant distribution, cage stability, and transfer film lubricants have been made. It is anticipated that further developments will be made in response to future aerospace requirements.

  8. Computational studies of nonstoichiometric sodium auride clusters.

    PubMed

    Lin, Ying-Chan; Sundholm, Dage

    2012-05-31

    The molecular structures of low-lying isomers of anionic and neutral sodium auride clusters have been studied computationally at the second-order Møller-Plesset perturbation theory level using quadruple-ζ basis sets augmented with a double set of polarization functions. The first vertical detachment energies were calculated at the Møller-Plesset level as the energy difference between the cluster anion and the corresponding neutral cluster. The photodetachment energies of higher-lying ionization channels were calculated by adding electronic excitation energies of the neutral clusters to the first vertical detachment energy. The excitation energies were calculated at the linear response approximate coupled-cluster singles and doubles level using the anionic cluster structures. The obtained ionization energies for NaAu(-), NaAu(2)(-), NaAu(3)(-), NaAu(4)(-), Na(2)Au(2)(-), Na(2)Au(3)(-), Na(3)Au(3)(-), and Na(2)Au(4)(-) were compared to values deduced from experimental photoelectron spectra. Comparison of the calculated photoelectron spectra for a few energetically low-lying isomers shows that the energetically lowest cluster structures obtained in the calculations do not always correspond to the clusters produced experimentally. Spin-component-scaled second-order Møller-Plesset perturbation theory calculations shift the order of the isomers such that the observed clusters more often correspond to the energetically lowest structure, whereas the spin-component-scaled approach does not improve the photodetachment energies of the sodium aurides. The potential energy surface of the sodium aurides is very soft, with several low-lying isomers requiring an accurate electron correlation treatment. The calculations show that merely the energetic criterion is not a reliable means to identify the structures of the observed sodium auride clusters; other experimental information is needed to ensure a correct assignment of the cluster structures. The cluster structures of

  9. Fault Tolerant Homopolar Magnetic Bearings

    NASA Technical Reports Server (NTRS)

    Li, Ming-Hsiu; Palazzolo, Alan; Kenny, Andrew; Provenza, Andrew; Beach, Raymond; Kascak, Albert

    2003-01-01

    Magnetic suspensions (MS) satisfy the long life and low loss conditions demanded by satellite and ISS based flywheels used for Energy Storage and Attitude Control (ACESE) service. This paper summarizes the development of a novel MS that improves reliability via fault tolerant operation. Specifically, flux coupling between poles of a homopolar magnetic bearing is shown to deliver desired forces even after termination of coil currents to a subset of failed poles . Linear, coordinate decoupled force-voltage relations are also maintained before and after failure by bias linearization. Current distribution matrices (CDM) which adjust the currents and fluxes following a pole set failure are determined for many faulted pole combinations. The CDM s and the system responses are obtained utilizing 1D magnetic circuit models with fringe and leakage factors derived from detailed, 3D, finite element field models. Reliability results are presented vs. detection/correction delay time and individual power amplifier reliability for 4, 6, and 7 pole configurations. Reliability is shown for two success criteria, i.e. (a) no catcher bearing contact following pole failures and (b) re-levitation off of the catcher bearings following pole failures. An advantage of the method presented over other redundant operation approaches is a significantly reduced requirement for backup hardware such as additional actuators or power amplifiers.

  10. The sodium/sulphur battery

    NASA Astrophysics Data System (ADS)

    Sudworth, J. L.

    1984-02-01

    Problems encountered in the design and development of a practical sodium/sulphur battery are reviewed and several solutions are offered. Consideration is given to the degradation of the solid electrolyte, beta alumina; problems with the sodium electrode associated with the sodium/beta alumina interface; and the loss of capacity identified with the sulphur electrode. Attention is also given to the search for corrosion-resistant materials for use as the current collector and to the geometry of the cell design. Criteria for a successful road vehicle battery are discussed.

  11. Sodium MRI: methods and applications.

    PubMed

    Madelin, Guillaume; Lee, Jae-Seung; Regatte, Ravinder R; Jerschow, Alexej

    2014-05-01

    Sodium NMR spectroscopy and MRI have become popular in recent years through the increased availability of high-field MRI scanners, advanced scanner hardware and improved methodology. Sodium MRI is being evaluated for stroke and tumor detection, for breast cancer studies, and for the assessment of osteoarthritis and muscle and kidney functions, to name just a few. In this article, we aim to present an up-to-date review of the theoretical background, the methodology, the challenges, limitations, and current and potential new applications of sodium MRI. PMID:24815363

  12. Sodium MRI: Methods and applications

    PubMed Central

    Madelin, Guillaume; Lee, Jae-Seung; Regatte, Ravinder R.; Jerschow, Alexej

    2014-01-01

    Sodium NMR spectroscopy and MRI have become popular in recent years through the increased availability of high-field MRI scanners, advanced scanner hardware and improved methodology. Sodium MRI is being evaluated for stroke and tumor detection, for breast cancer studies, and for the assessment of osteoarthritis and muscle and kidney functions, to name just a few. In this article, we aim to present an up-to-date review of the theoretical background, the methodology, the challenges and limitations, and current and potential new applications of sodium MRI. PMID:24815363

  13. Cannibalism and predation on black bears by grizzly bears in the Yellowstone ecosystem, 1975-1990

    USGS Publications Warehouse

    Mattson, D.J.; Knight, R.R.; Blanchard, B.M.

    1992-01-01

    We documented one instance of an adult male grizzly bear preying upon a black bear and four instances where circumstantial evidence suggested that grizzly bears (two cubs-of-the-year, one yearling female that was injured, and one adult male) had been preyed upon by conspecifics. We also examined feces of grizzly bears for bear remains. Remains of bears tended to be more common in spring feces and did not differ in frequency between early and late years of the study. Our observations generally support existing hypotheses concerning cannibalism among bears.

  14. Equations For Elastohydrodynamic Lubrication Of Bearings

    NASA Technical Reports Server (NTRS)

    Zaretsky, Erwin V.

    1993-01-01

    Equation for thickness of elastohydrodynamic (EHD) lubricant film in rolling-element bearing reduced to simplified form involving only inside and outside diameters of bearing, speed of rotation, parameter related to type of lubricant, and viscosity of lubricant at temperature of bearing. In addition, experimentally derived graph of EHD-film-thickness-reduction factor as function of contact-lubricant-flow number. Accounts for lubricant starvation within Hertzian contact. Graph relating ratio of minimum film thickness to composite roughness of bearing surfaces and to lubrication-life correction factor also provided. Life-correction factor used to determine resultant life of bearing.

  15. Heuristic explanation of journal bearing instability

    NASA Technical Reports Server (NTRS)

    Crandall, S. H.

    1982-01-01

    A fluid-filled journal bearing is viewed as a powerful pump circulating fluid around the annular space between the journal and the bearing. A small whirling motion of the journal generates a wave of thickness variation progressing around the channel. The hypothesis that the fluid flow drives the whirl whenever the mean of the pumped fluid velocity is greater than the peripheral speed of the thickness variation wave is discussed and compared with other simple explanations of journal bearing instability. It is shown that for non-cavitation long bearings the hypothesis predicts instability onset correctly for unloaded bearings but gradually overpredicts the onset speed as the load is increased.

  16. Valve assembly having remotely replaceable bearings

    DOEpatents

    Johnson, Evan R.; Tanner, David E.

    1980-01-01

    A valve assembly having remotely replaceable bearings is disclosed wherein a valve disc is supported within a flow duct for rotation about a pair of axially aligned bearings, one of which is carried by a spindle received within a diametral bore in the valve disc, and the other of which is carried by a bearing support block releasably mounted on the duct circumferentially of an annular collar on the valve disc coaxial with its diametrical bore. The spindle and bearing support block are adapted for remote removal to facilitate servicing or replacement of the valve disc support bearings.

  17. Ball Bearing Analysis with the ORBIS Tool

    NASA Technical Reports Server (NTRS)

    Halpin, Jacob D.

    2016-01-01

    Ball bearing design is critical to the success of aerospace mechanisms. Key bearing performance parameters, such as load capability, stiffness, torque, and life all depend on accurate determination of the internal load distribution. Hence, a good analytical bearing tool that provides both comprehensive capabilities and reliable results becomes a significant asset to the engineer. This paper introduces the ORBIS bearing tool. A discussion of key modeling assumptions and a technical overview is provided. Numerous validation studies and case studies using the ORBIS tool are presented. All results suggest the ORBIS code closely correlates to predictions on bearing internal load distributions, stiffness, deflection and stresses.

  18. Mechanism of sodium chloride in promoting reduction of high-magnesium low-nickel oxide ore

    PubMed Central

    Zhou, Shiwei; Wei, Yonggang; Li, Bo; Wang, Hua; Ma, Baozhong; Wang, Chengyan

    2016-01-01

    Sodium chloride has been proved that it is an effective promoter for the reduction of high-magnesium, low-nickel oxide ore. The aim of current work is to clarify the promotion behavior of sodium chloride in the roasting reduction process. The influence of moisture on the reduction of ore in the presence of sodium chloride is studied to get clear comprehension of promotion process. In the presence of moisture, the HCl is produced by pyrohydrolysis of sodium chloride for chlorinating nickel and iron oxides, moreover, interactions between metallic oxides and sodium chloride are also a way for chlorination at high temperature (>802 °C); subsequently, the metal chloride would be reduced by reductant. In the absence of moisture, the magnetic separation results show that the recoveries of iron and nickel have a significant increase; moreover, olivine structure would be destroyed gradually with the increase of roasting temperature in the action of sodium chloride, and the sodium chloride existed in high-magnesium, low-nickel oxide ore could make the NiO isolate from NiO-bearing minerals. The NiO reacts with Fe2O3 at high temperature to form NiFe2O4, which is conductive to the formation of Ni-Fe alloy during the reduction process. PMID:27374991

  19. Mechanism of sodium chloride in promoting reduction of high-magnesium low-nickel oxide ore.

    PubMed

    Zhou, Shiwei; Wei, Yonggang; Li, Bo; Wang, Hua; Ma, Baozhong; Wang, Chengyan

    2016-01-01

    Sodium chloride has been proved that it is an effective promoter for the reduction of high-magnesium, low-nickel oxide ore. The aim of current work is to clarify the promotion behavior of sodium chloride in the roasting reduction process. The influence of moisture on the reduction of ore in the presence of sodium chloride is studied to get clear comprehension of promotion process. In the presence of moisture, the HCl is produced by pyrohydrolysis of sodium chloride for chlorinating nickel and iron oxides, moreover, interactions between metallic oxides and sodium chloride are also a way for chlorination at high temperature (>802 °C); subsequently, the metal chloride would be reduced by reductant. In the absence of moisture, the magnetic separation results show that the recoveries of iron and nickel have a significant increase; moreover, olivine structure would be destroyed gradually with the increase of roasting temperature in the action of sodium chloride, and the sodium chloride existed in high-magnesium, low-nickel oxide ore could make the NiO isolate from NiO-bearing minerals. The NiO reacts with Fe2O3 at high temperature to form NiFe2O4, which is conductive to the formation of Ni-Fe alloy during the reduction process. PMID:27374991

  20. Mechanism of sodium chloride in promoting reduction of high-magnesium low-nickel oxide ore

    NASA Astrophysics Data System (ADS)

    Zhou, Shiwei; Wei, Yonggang; Li, Bo; Wang, Hua; Ma, Baozhong; Wang, Chengyan

    2016-07-01

    Sodium chloride has been proved that it is an effective promoter for the reduction of high-magnesium, low-nickel oxide ore. The aim of current work is to clarify the promotion behavior of sodium chloride in the roasting reduction process. The influence of moisture on the reduction of ore in the presence of sodium chloride is studied to get clear comprehension of promotion process. In the presence of moisture, the HCl is produced by pyrohydrolysis of sodium chloride for chlorinating nickel and iron oxides, moreover, interactions between metallic oxides and sodium chloride are also a way for chlorination at high temperature (>802 °C) subsequently, the metal chloride would be reduced by reductant. In the absence of moisture, the magnetic separation results show that the recoveries of iron and nickel have a significant increase; moreover, olivine structure would be destroyed gradually with the increase of roasting temperature in the action of sodium chloride, and the sodium chloride existed in high-magnesium, low-nickel oxide ore could make the NiO isolate from NiO-bearing minerals. The NiO reacts with Fe2O3 at high temperature to form NiFe2O4, which is conductive to the formation of Ni-Fe alloy during the reduction process.

  1. Chromatographic (TLC) differentiation of grizzly bear and black bear scats

    USGS Publications Warehouse

    Picton, Harold D.; Kendall, Katherine C.

    1994-01-01

    While past work concluded that thin-layer chromatography (TLC) was inadequate for the separation of grizzly (Ursus arctos horribilis) and black bear (U. americanus) scats, our study found differences adequate for species separation. A key was constructed using 19 of 40 data points recorded on each(N)=356 profiles of 178) know-species scat. Accuracy was best for late summer scats (94%). Methods for specimen preparation, analysis, and reading the TLC profiles are discussed. Factors involved in scat variation were tested.

  2. CALANDRIA TYPE SODIUM GRAPHITE REACTOR

    DOEpatents

    Peterson, R.M.; Mahlmeister, J.E.; Vaughn, N.E.; Sanders, W.J.; Williams, A.C.

    1964-02-11

    A sodium graphite power reactor in which the unclad graphite moderator and fuel elements are contained within a core tank is described. The core tank is submersed in sodium within the reactor vessel. Extending longitudinally through the core thnk are process tubes with fuel elements positioned therein. A bellows sealing means allows axial expansion and construction of the tubes. Within the core tank, a leakage plenum is located below the graphite, and above the graphite is a gas space. A vent line regulates the gas pressure in the space, and another line removes sodium from the plenum. The sodium coolant flows from the lower reactor vessel through the annular space between the fuel elements and process tubes and out into the reactor vessel space above the core tank. From there, the heated coolant is drawn off through an outlet line and sent to the heat exchange. (AEC)

  3. Lubrication for high load duplex bearings

    SciTech Connect

    Steinhoff, R.G.

    1997-08-01

    Three ES and H-compatible lubricants (Environment, Safety and Health) for high load duplex bearing applications were evaluated and compared against trichlorotrifluoroethane (Freon) deposition of low molecular weight polytetrafluoroethylene (PTFE) bearing lubricant extracted from Vydax{trademark}. Vydax is a product manufactured by DuPont consisting of various molecular weights of PTFE suspended in trichlorotrifluoroethane (Freon) which is an ozone-depleting solvent. Bearings with Supercritical CO{sub 2} deposition of PTFE extracted from Vydax AR/IPA, bearings with titanium carbide coated balls, and bearings with diamond-like carbon races and retainers were evaluated. Bearings with Supercritical CO{sub 2} deposition of PTFE from Vydax AR/IPA performed as well as bearings with Freon deposition of PTFE from Freon-based Vydax.

  4. Pratt and Whitney cryogenic turbopump bearing experience

    NASA Technical Reports Server (NTRS)

    Poole, W. E.; Bursey, R. W., Jr.

    1988-01-01

    Successful, reusable bearings require lubrication, traditionally, a transfer film from sacrificial cage wear. Early testing included materials screening programs to identify suitable cryogenic cage materials. A specially developed element tester that simulated the function of a ball bearing cage was used. Suitable materials must provide lubrication with an acceptably low wear rate, without abrading contacting surfaces. The most promising materials were tested in full scale bearings at speeds up to 4 MDN. Teflon, filled with 40 percent bronze powder, was the best performing material. A variety of bearings were designed and successfully tested in LH2 and LOX. Bearings with bronze filled Teflon cages were successfully tested for 150 hrs. In overload tests, the same design was tested for 5 hrs at maximum Hertz stresses above 450 ksi and an additional 5 hrs with a maximum Hertz stress exceeding 500 ksi. Four bearings were tested in LOX for 25 hrs, with a maximum time per bearing of 10 hrs.

  5. Contact Sensors on Ceramic Ball Bearings

    NASA Astrophysics Data System (ADS)

    Yi, Jia; Just-Agosto, Frederick; Romero, Edwar

    2002-01-01

    Integration of micro contact sensors onto a ball bearing is a critical technology necessary for on-line bearing health monitoring in an industrial harsh environment and evaluation of the bearing performance and design. The current planner fabrication methods offered by the MEMS technology restrict the possibility of integrating micro sensor onto a double contoured bearing surface in a more traditional manufacturing environment. We have developed an unique technique to directly fabricate micron-sized pressure and temperature sensors onto a miniature ceramic ball bearing. A complete fabrication process, based on sensor design, surface preparation, optimized sputtering parameters, photolithographic techniques and sensor post-treatment, is described. Pressure and temperature measurement results on a miniature ceramic ball bearing show good correlation with numerical thermal-EHL analysis and good wear resistance. Keywords: Ball Bearing, Thin film Sensor, Pressure sensor, Temperature Sensor, adhesion, wear resistance, Non-developable surface, and thermal-EHL.

  6. Design review of fluid film bearing testers

    NASA Technical Reports Server (NTRS)

    Scharrer, Joseph K.

    1993-01-01

    The designs of three existing testers (Hybrid Bearing Tester, OTV Bearing Tester, and Long Life Bearing Tester) owned by NASA were reviewed for their capability to serve as a multi-purpose cryogenic fluid film bearing tester. The primary tester function is the validation of analytical predictions for fluid film bearing steady state and dynamic performance. Evaluation criteria were established for test bearing configurations, test fluids, instrumentation, and test objectives. Each tester was evaluated with respect to these criteria. A determination was made of design improvements which would allow the testers to meet the stated criteria. The cost and time required to make the design changes were estimated. A recommendation based on the results of this study was made to proceed with the Hybrid Bearing Tester.

  7. Wave Journal Bearings Under Dynamic Loads

    NASA Technical Reports Server (NTRS)

    Hendricks, Robert C.; Dimofte, Florin

    2002-01-01

    The dynamic behavior of the wave journal bearing was determined by running a three-wave bearing with an eccentrically mounted shaft. A transient analysis was developed and used to predict numerical data for the experimental cases. The three-wave journal bearing ran stably under dynamic loads with orbits well inside the bearing clearance. The orbits were almost circular and nearly free of the influence of, but dynamically dependent on, bearing wave shape. Experimental observations for both the absolute bearing-housing-center orbits and the relative bearing-housing-center-to-shaft-center orbits agreed well with the predictions. Moreover, the subsynchronous whirl motion generated by the fluid film was found experimentally and predicted theoretically for certain speeds.

  8. Evaluation of rotating, incompressibly lubricated, pressurized thrust bearings

    NASA Technical Reports Server (NTRS)

    Fleming, D. P.

    1971-01-01

    Program evaluates a series hybrid, fluid film ball bearing consisting of an orifice compensated pressurized thrust bearing in conjunction with a self-acting journal bearing. Oil viscosities corresponding to experimentally measured ball bearing outer-race temperatures were used.

  9. Genomic evidence of geographically widespread effect of gene flow from polar bears into brown bears

    PubMed Central

    Cahill, James A; Stirling, Ian; Kistler, Logan; Salamzade, Rauf; Ersmark, Erik; Fulton, Tara L; Stiller, Mathias; Green, Richard E; Shapiro, Beth

    2015-01-01

    Polar bears are an arctic, marine adapted species that is closely related to brown bears. Genome analyses have shown that polar bears are distinct and genetically homogeneous in comparison to brown bears. However, these analyses have also revealed a remarkable episode of polar bear gene flow into the population of brown bears that colonized the Admiralty, Baranof and Chichagof islands (ABC islands) of Alaska. Here, we present an analysis of data from a large panel of polar bear and brown bear genomes that includes brown bears from the ABC islands, the Alaskan mainland and Europe. Our results provide clear evidence that gene flow between the two species had a geographically wide impact, with polar bear DNA found within the genomes of brown bears living both on the ABC islands and in the Alaskan mainland. Intriguingly, while brown bear genomes contain up to 8.8% polar bear ancestry, polar bear genomes appear to be devoid of brown bear ancestry, suggesting the presence of a barrier to gene flow in that direction. PMID:25490862

  10. Genomic evidence of geographically widespread effect of gene flow from polar bears into brown bears.

    PubMed

    Cahill, James A; Stirling, Ian; Kistler, Logan; Salamzade, Rauf; Ersmark, Erik; Fulton, Tara L; Stiller, Mathias; Green, Richard E; Shapiro, Beth

    2015-03-01

    Polar bears are an arctic, marine adapted species that is closely related to brown bears. Genome analyses have shown that polar bears are distinct and genetically homogeneous in comparison to brown bears. However, these analyses have also revealed a remarkable episode of polar bear gene flow into the population of brown bears that colonized the Admiralty, Baranof and Chichagof islands (ABC islands) of Alaska. Here, we present an analysis of data from a large panel of polar bear and brown bear genomes that includes brown bears from the ABC islands, the Alaskan mainland and Europe. Our results provide clear evidence that gene flow between the two species had a geographically wide impact, with polar bear DNA found within the genomes of brown bears living both on the ABC islands and in the Alaskan mainland. Intriguingly, while brown bear genomes contain up to 8.8% polar bear ancestry, polar bear genomes appear to be devoid of brown bear ancestry, suggesting the presence of a barrier to gene flow in that direction. PMID:25490862

  11. [Hypolactatemic effect of sodium difluoroacetate].

    PubMed

    Dalstein, J M; Ribes, G; Campo, P; Loubatières-Mariani, M M

    1980-01-01

    In the anesthetized rat, the intraperitoneal injection of 40 mg/kg sodium difluoroacetate (DFA), an activator of the pyruvate dehydrogenase, counteracted the hyperlactatemia induced by a high dose of phenformin (40 mg/kg) injected concomitantly. In the normal conscious dog, the administration of 150 mg/kg by gastric intubation decreased the blood lactate and pyruvate levels; however, this effect was less marked than that produced by the same dose of sodium dichloroacetate (DCA). PMID:6449260

  12. Designing prosthetic knee joints with bio-inspired bearing surfaces.

    PubMed

    Qiu, Mingfeng; Chyr, Anthony; Sanders, Anthony P; Raeymaekers, Bart

    2014-09-01

    It has long been known that articular cartilage exhibits a surface microtexture with shallow indentations. By contrast, prosthetic joints consist of ultra-smooth bearing surfaces, the longevity of which does not reach that of natural cartilage. We show that adding a microtexture to the smooth femoral component of a prosthetic knee joint reduces friction by increasing the lubricant film thickness between the bearing surfaces of the knee. We have implemented an elastohydrodynamic lubrication model to optimize the geometry of the microtexture, while taking into account the deformation of the polyethylene tibial insert. We have manufactured several microtexture designs on a surrogate femoral component, and experimentally demonstrate that the microtexture reduces friction between the surrogate femoral component and tibial insert. PMID:25049441

  13. Performance analysis of bearings-only tracking algorithm

    NASA Astrophysics Data System (ADS)

    van Huyssteen, David; Farooq, Mohamad

    1998-07-01

    A number of 'bearing-only' target motion analysis algorithms have appeared in the literature over the years, all suited to track an object based solely on noisy measurements of its angular position. In their paper 'Utilization of Modified Polar (MP) Coordinates for Bearings-Only Tracking' Aidala and Hammel advocate a filter in which the observable and unobservable states are naturally decoupled. While the MP filter has certain advantages over Cartesian and pseudolinear extended Kalman filters, it does not escape the requirement for the observer to steer an optimum maneuvering course to guarantee acceptable performance. This paper demonstrates by simulation the consequence if the observer deviates from this profile, even if it is sufficient to produce full state observability.

  14. Development and Evaluation of Titanium Spacesuit Bearings

    NASA Technical Reports Server (NTRS)

    Rhodes, Richard; Battisti, Brian; Ytuarte, Raymond, Jr.; Schultz, Bradley

    2016-01-01

    The Z-2 Prototype Planetary Extravehicular Space Suit Assembly is a continuation of NASA's Z-series of spacesuits, designed with the intent of meeting a wide variety of exploration mission objectives, including human exploration of the Martian surface. Incorporating titanium bearings into the Z-series space suit architecture allows us to reduce mass by an estimated 23 lbs per suit system compared to the previously used stainless steel bearing race designs, without compromising suit functionality. There are two obstacles to overcome when using titanium for a bearing race- 1) titanium is flammable when exposed to the oxygen wetted environment inside the space suit and 2) titanium's poor wear properties are often challenging to overcome in tribology applications. In order to evaluate the ignitability of a titanium space suit bearing, a series of tests were conducted at White Sands Test Facility (WSTF) that introduced the bearings to an extreme test profile, with multiple failures imbedded into the test bearings. The testing showed no signs of ignition in the most extreme test cases; however, substantial wear of the bearing races was observed. In order to design a bearing that can last an entire exploration mission (approx. 3 years), design parameters for maximum contact stress need to be identified. To identify these design parameters, bearing test rigs were developed that allow for the quick evaluation of various bearing ball loads, ball diameters, lubricants, and surface treatments. This test data will allow designers to minimize the titanium bearing mass for a specific material and lubricant combination and design around a cycle life requirement for an exploration mission. This paper reviews the current research and testing that has been performed on titanium bearing races to evaluate the use of such materials in an enriched oxygen environment and to optimize the bearing assembly mass and tribological properties to accommodate for the high bearing cycle life for an

  15. Sodium and water: an overview.

    PubMed

    Papper, S

    1976-01-01

    The renal regulation of sodium is intertwined with the extracellular fluid volume (ECFV). Most adjustments in sodium elimination in man are accomplished via alterations in tubular reabsorption. The latter is sensitive to change in ECFV. An expanded ECFV results in less reabsorption and more excretion of sodium, and a contracted ECFV has the converse effect. There are direct and indirect mechanisms whereby ECFV influences sodium reabsorption. Patients with nephrotic syndrome, heart failure, and cirrhosis "behave" physiologically as normal individuals with a contracted ECFV. Water balance is normally determined by intake and losses in sweat which is always hypoosmotic to plasma, by evaporation from skin and lungs, and through renal excretion. The major factors that determine the ability to concentrate the urine are (1) the establishment of a concentrated environment around the collecting ducts, and (2) the elaboration and effects on the kidney of antidiuretic hormone. The evaluation of a patient with abnormalities of sodium and water rests initially and largely on clinical information. The clinical setting provides clues to anticipating, preventing, and interpreting distortions of body sodium and water. The laboratory can detect an abnormality, confirm or refute clinical assessment, and assist in the quantitative aspects of treatment and its efficacy. PMID:961714

  16. Hydrostatic bearings for a turbine fluid flow metering device

    DOEpatents

    Fincke, J.R.

    1980-05-02

    A rotor assembly fluid metering device has been improved by development of a hydrostatic bearing fluid system which provides bearing fluid at a common pressure to rotor assembly bearing surfaces. The bearing fluid distribution system produces a uniform film of fluid distribution system produces a uniform film of fluid between bearing surfaces and allows rapid replacement of bearing fluid between bearing surfaces, thereby minimizing bearing wear and corrosion.

  17. Are Reductions in Population Sodium Intake Achievable?

    PubMed Central

    Levings, Jessica L.; Cogswell, Mary E.; Gunn, Janelle Peralez

    2014-01-01

    The vast majority of Americans consume too much sodium, primarily from packaged and restaurant foods. The evidence linking sodium intake with direct health outcomes indicates a positive relationship between higher levels of sodium intake and cardiovascular disease risk, consistent with the relationship between sodium intake and blood pressure. Despite communication and educational efforts focused on lowering sodium intake over the last three decades data suggest average US sodium intake has remained remarkably elevated, leading some to argue that current sodium guidelines are unattainable. The IOM in 2010 recommended gradual reductions in the sodium content of packaged and restaurant foods as a primary strategy to reduce US sodium intake, and research since that time suggests gradual, downward shifts in mean population sodium intake are achievable and can move the population toward current sodium intake guidelines. The current paper reviews recent evidence indicating: (1) significant reductions in mean population sodium intake can be achieved with gradual sodium reduction in the food supply, (2) gradual sodium reduction in certain cases can be achieved without a noticeable change in taste or consumption of specific products, and (3) lowering mean population sodium intake can move us toward meeting the current individual guidelines for sodium intake. PMID:25325254

  18. 21 CFR 184.1763 - Sodium hydroxide.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... hydroxide is prepared commercially by the electrolysis of sodium chloride solution and also by reacting... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sodium hydroxide. 184.1763 Section 184.1763 Food... GRAS § 184.1763 Sodium hydroxide. (a) Sodium hydroxide (NaOH, CAS Reg. No. 1310-73-2) is also known...

  19. 21 CFR 184.1724 - Sodium alginate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Sodium alginate. 184.1724 Section 184.1724 Food... Specific Substances Affirmed as GRAS § 184.1724 Sodium alginate. (a) Sodium alginate (CAS Reg. No. 9005-38-3) is the sodium salt of alginic acid, a natural polyuronide constituent of certain brown...

  20. 21 CFR 172.170 - Sodium nitrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Sodium nitrate. 172.170 Section 172.170 Food and... Preservatives § 172.170 Sodium nitrate. The food additive sodium nitrate may be safely used in or on specified... follows: (1) As a preservative and color fixative, with or without sodium nitrite, in smoked,...

  1. 21 CFR 173.73 - Sodium polyacrylate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Sodium polyacrylate. 173.73 Section 173.73 Food... Polymer Substances and Polymer Adjuvants for Food Treatment § 173.73 Sodium polyacrylate. Sodium... the polyacrylic acid with an aqueous sodium hydroxide solution. As determined by a method...

  2. 21 CFR 172.175 - Sodium nitrite.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Sodium nitrite. 172.175 Section 172.175 Food and... Preservatives § 172.175 Sodium nitrite. The food additive sodium nitrite may be safely used in or on specified... follows: (1) As a color fixative in smoked cured tunafish products so that the level of sodium...

  3. 21 CFR 582.2727 - Sodium aluminosilicate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Sodium aluminosilicate. 582.2727 Section 582.2727 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Sodium aluminosilicate. (a) Product. Sodium aluminosilicate (sodium silicoaluminate). (b) Tolerance....

  4. 21 CFR 182.2727 - Sodium aluminosilicate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium aluminosilicate. 182.2727 Section 182.2727 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD... Sodium aluminosilicate. (a) Product. Sodium aluminosilicate (sodium silicoaluminate). (b) Tolerance....

  5. 21 CFR 172.175 - Sodium nitrite.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Sodium nitrite. 172.175 Section 172.175 Food and... Preservatives § 172.175 Sodium nitrite. The food additive sodium nitrite may be safely used in or on specified... follows: (1) As a color fixative in smoked cured tunafish products so that the level of sodium...

  6. 21 CFR 186.1750 - Sodium chlorite.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Sodium chlorite. 186.1750 Section 186.1750 Food... of Specific Substances Affirmed as GRAS § 186.1750 Sodium chlorite. (a) Sodium chlorite (NaCLO2, CAS... passing chlorine dioxide into a solution of sodium hydroxide and hydrogen peroxide. (b) the ingredient...

  7. 21 CFR 182.2727 - Sodium aluminosilicate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Sodium aluminosilicate. 182.2727 Section 182.2727 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD... Sodium aluminosilicate. (a) Product. Sodium aluminosilicate (sodium silicoaluminate). (b) Tolerance....

  8. 21 CFR 186.1750 - Sodium chlorite.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Sodium chlorite. 186.1750 Section 186.1750 Food... of Specific Substances Affirmed as GRAS § 186.1750 Sodium chlorite. (a) Sodium chlorite (NaCLO2, CAS... passing chlorine dioxide into a solution of sodium hydroxide and hydrogen peroxide. (b) the ingredient...

  9. 21 CFR 182.2727 - Sodium aluminosilicate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Sodium aluminosilicate. 182.2727 Section 182.2727 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD... Sodium aluminosilicate. (a) Product. Sodium aluminosilicate (sodium silicoaluminate). (b) Tolerance....

  10. 21 CFR 184.1724 - Sodium alginate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Sodium alginate. 184.1724 Section 184.1724 Food... Specific Substances Affirmed as GRAS § 184.1724 Sodium alginate. (a) Sodium alginate (CAS Reg. No. 9005-38-3) is the sodium salt of alginic acid, a natural polyuronide constituent of certain brown...

  11. 21 CFR 172.170 - Sodium nitrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Sodium nitrate. 172.170 Section 172.170 Food and... Preservatives § 172.170 Sodium nitrate. The food additive sodium nitrate may be safely used in or on specified... follows: (1) As a preservative and color fixative, with or without sodium nitrite, in smoked,...

  12. 21 CFR 184.1792 - Sodium sesquicarbonate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Sodium sesquicarbonate. 184.1792 Section 184.1792... Listing of Specific Substances Affirmed as GRAS § 184.1792 Sodium sesquicarbonate. (a) Sodium... naturally occurring impure sodium sesquicarbonate. (b) The ingredient meets the specifications of the...

  13. 21 CFR 582.2727 - Sodium aluminosilicate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Sodium aluminosilicate. 582.2727 Section 582.2727 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Sodium aluminosilicate. (a) Product. Sodium aluminosilicate (sodium silicoaluminate). (b) Tolerance....

  14. 21 CFR 172.175 - Sodium nitrite.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium nitrite. 172.175 Section 172.175 Food and... Preservatives § 172.175 Sodium nitrite. The food additive sodium nitrite may be safely used in or on specified... follows: (1) As a color fixative in smoked cured tunafish products so that the level of sodium...

  15. 21 CFR 173.73 - Sodium polyacrylate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Sodium polyacrylate. 173.73 Section 173.73 Food... Polymer Substances and Polymer Adjuvants for Food Treatment § 173.73 Sodium polyacrylate. Sodium... the polyacrylic acid with an aqueous sodium hydroxide solution. As determined by a method...

  16. 21 CFR 182.2727 - Sodium aluminosilicate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Sodium aluminosilicate. 182.2727 Section 182.2727 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD... Sodium aluminosilicate. (a) Product. Sodium aluminosilicate (sodium silicoaluminate). (b) Tolerance....

  17. 21 CFR 582.1745 - Sodium carboxymethylcellulose.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Sodium carboxymethylcellulose. 582.1745 Section... Food Additives § 582.1745 Sodium carboxymethylcellulose. (a) Product. Sodium carboxymethyl- cellulose is the sodium salt of carboxymethylcellulose not less than 99.5 percent on a dry-weight basis,...

  18. 21 CFR 186.1750 - Sodium chlorite.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Sodium chlorite. 186.1750 Section 186.1750 Food... of Specific Substances Affirmed as GRAS § 186.1750 Sodium chlorite. (a) Sodium chlorite (NaCLO2, CAS... passing chlorine dioxide into a solution of sodium hydroxide and hydrogen peroxide. (b) the ingredient...

  19. 21 CFR 582.1745 - Sodium carboxymethylcellulose.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Sodium carboxymethylcellulose. 582.1745 Section... Food Additives § 582.1745 Sodium carboxymethylcellulose. (a) Product. Sodium carboxymethyl- cellulose is the sodium salt of carboxymethylcellulose not less than 99.5 percent on a dry-weight basis,...

  20. 21 CFR 184.1792 - Sodium sesquicarbonate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sodium sesquicarbonate. 184.1792 Section 184.1792... GRAS § 184.1792 Sodium sesquicarbonate. (a) Sodium sesquicarbonate (Na2CO3·NaHCO3·2H2O, CAS Reg. No..., centrifugation, and drying; (2) double refining of trona ore, a naturally occurring impure sodium...