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Sample records for ardennes b-2 reactor

  1. Light water reactor aerosol containment experiment LA4 simulated by JERICHO and AEROSOLS-B2 codes

    SciTech Connect

    Passalacqua, R.; Tarabelli, D.; Renault, C.

    1996-12-01

    Large-scale experiments show that whenever a loss of coolant accident occurs water pools are generated. Stratification of steam-saturated gas develops above growing water pools causing a different thermal hydraulics in the subcompartment where the water pool is located. Hereafter, the LWR Aerosols Containment Experiment (LACE) LA4 experiment, performed at the Hanford Engineering Development Laboratory, will be studied; this experiment exhibited a strong stratification, at all times, above a growing wade pool. JERICHO and AEROSOLS-B2 are part of the Ensemble de Systemes de Codes d`Analyse d`Accident des Reacteurs a Eau (ESCADRE) code system, a tool for evaluating the response of a nuclear plant to severe accidents. These two codes are used here to simulate respectively the thermal hydraulics and the associated aerosol behavior. Code results have shown that modeling large containment thermal hydraulics without taking into account the stratification phenomenon leads to large overpredictions of containment pressure and temperature. If the stratification, above the water pool, is modeled as a zone with a higher steam condensation rate and a higher thermal resistance (that is acting as a barrier to heat exchanges with the upper and larger compartment), ESCADRE predictions match experimental data quite well. The stratification region is believed to be able to affect aerosol behavior; aerosol settling is improved by steam condensation on particles and by diffusiophoresis and thermophoresis. In addition, the lower aerosol concentration throughout the stratification might cause a nonnegligible aerosol concentration gradient and consequently a driving force for the motion of smaller particles toward the pool.

  2. Evaluation of long-term bedload virtual velocity in gravel-bed rivers (Ardenne, Belgium)

    NASA Astrophysics Data System (ADS)

    Houbrechts, Geoffrey; Levecq, Yannick; Peeters, Alexandre; Hallot, Eric; Van Campenhout, Jean; Denis, Anne-Cécile; Petit, François

    2015-12-01

    In many gravel-bed rivers, bed material transfer has been interrupted or perturbed by anthropogenic activities. Currently, restoration projects are being conducted in many countries in order to re-establish bedload continuity. However, until now, few studies have provided indications of the velocity of bed material over the long-term (at least decade to century time-scale). In the context of river restoration projects (e.g. weir removal, addition of spawning gravel), these data are nevertheless crucial to predict the downstream propagation of the geomorphological and biological benefits (e.g. supply-transport equilibrium, morphological and substratum diversity). In our study, PIT-tag tracers were used in eight medium-sized gravel-bed rivers (Ardenne Region, Belgium) to propose a flow competence relationship based on specific stream power, on the one hand, and to determine the long-term virtual velocity of the bed material corresponding to the median diameter (D50) of the surface layer of riffles, on the other hand. After each flow event that exceeded the threshold for sediment entrainment, tagged particles were sought and located, even when they were buried in the subsurface layer. Afterwards, all of the data were used to estimate the virtual velocity of the bed material over the long-term using three approaches. Finally, the results were compared with long-term transport estimations based on iron slag dispersed by the rivers since the end of the middle ages.

  3. Radar rainfall estimation of stratiform winter precipitation in the Belgian Ardennes

    NASA Astrophysics Data System (ADS)

    Hazenberg, P.; Leijnse, H.; Uijlenhoet, R.

    2010-12-01

    Radars are known for their ability to obtain a wealth of information about spatial storm field characteristics. Unfortunately, rainfall estimates obtained by this instrument are known to be affected by multiple sources of error. Especially for stratiform precipitation systems, the quality of radar rainfall estimates starts to decrease at relatively close ranges. In the current study the hydrological potential of weather radar is analyzed during a winter half-year for the hilly region of the Belgian Ardennes. A correction algorithm is proposed which corrects the radar data for errors related to attenuation, ground clutter, anomalous propagation, the vertical profile of reflectivity (VPR) and advection. No final bias correction with respect to rain gauge data was implemented, because that does not add to a better understanding of the quality of the radar. The impact of the different corrections is then being compared to rainfall information sampled by 42 hourly rain gauges. The largest improvement in the quality of the radar data is obtained by correcting for ground clutter. The impact of VPR correction and advection depends on the spatial variability and velocity of the precipitation system. Overall during the winter period, the radar underestimates the amount of precipitation as compared to the rain gauges. Remaining differences between both devices can be attributed to spatial and temporal variability in the type of precipitation which has not been taken into account.

  4. Impact of beaver ponds on river discharge and sediment deposition along the Chevral River, Ardennes, Belgium

    NASA Astrophysics Data System (ADS)

    Nyssen, Jan; Frankl, Amaury; Pontzeele, Jolien; De Visscher, Maarten; Billi, Paolo

    2013-04-01

    With the recovery of the European beaver (Castor fiber) and their capacity to engineer fluvial landscapes, questions arise as to how they influence river discharge and sediment transport. The Chevral river (Ardennes, Belgium) contains two beaver dam sequences which appeared in 2004 and count now about 30 dams. Flow discharges and sediment fluxes were measured at the in- and outflow of each dam sequence. Volumes of sediment deposited behind the dams were measured. Between 2004 and 2011, peak flows were topped off, and the magnitude of extreme events decreased. 1710 m³ of sediment were deposited behind the beaver dams, with an average sediment thickness of 25 cm. The thickness of the sediment layer is related to the area of the beaver ponds. Along the stream, beaver pond sediment thickness displayed a sinusoidal deposition pattern, in which ponds with thick sediment layers were preceded by a series of ponds with thinner sediment layers. A downstream textural coarsening in the dam sequences was also observed, probably due to dam failures subsequent to surges. Differences in sediment flux between the in- and outflow at the beaver pond sequence were related to the river hydrograph, with deposition taking place during the rising limbs and slight erosion during the falling limbs. The seven-year-old sequences have filtered 190 tons of sediment out of the Chevral river, which is of the same order of magnitude as the 374 tons measured in pond deposits, with the difference between the values corresponding to beaver excavations (60 tons), inflow from small tributaries, and runoff from the valley flanks. Hydrogeomorphic effects of C. fiber and C. canadensis activity are similar in magnitude. The detailed analysis of changes to hydrology in beaver pond sequences confirms the potential of beavers to contribute to river and wetland restoration and catchment management.

  5. REACTOR

    DOEpatents

    Szilard, L.

    1963-09-10

    A breeder reactor is described, including a mass of fissionable material that is less than critical with respect to unmoderated neutrons and greater than critical with respect to neutrons of average energies substantially greater than thermal, a coolant selected from sodium or sodium--potassium alloys, a control liquid selected from lead or lead--bismuth alloys, and means for varying the quantity of control liquid in the reactor. (AEC)

  6. Comparison of two landslide susceptibility assessments in the Champagne-Ardenne region (France)

    NASA Astrophysics Data System (ADS)

    Den Eeckhaut, M. Van; Marre, A.; Poesen, J.

    2010-02-01

    The vineyards of the Montagne de Reims are mostly planted on steep south-oriented cuesta fronts receiving a maximum of sun radiation. Due to the location of the vineyards on steep hillslopes, the viticultural activity is threatened by slope failures. This study attempts to better understand the spatial patterns of landslide susceptibility in the Champagne-Ardenne region by comparing a heuristic (qualitative) and a statistical (quantitative) model in a 1120 km² study area. The heuristic landslide susceptibility model was adopted from the Bureau de Recherches Géologiques et Minières, the GEGEAA - Reims University and the Comité Interprofessionnel du Vin de Champagne. In this model, expert knowledge of the region was used to assign weights to all slope classes and lithologies present in the area, but the final susceptibility map was never evaluated with the location of mapped landslides. For the statistical landslide susceptibility assessment, logistic regression was applied to a dataset of 291 'old' (Holocene) landslides. The robustness of the logistic regression model was evaluated and ROC curves were used for model calibration and validation. With regard to the variables assumed to be important environmental factors controlling landslides, the two models are in agreement. They both indicate that present and future landslides are mainly controlled by slope gradient and lithology. However, the comparison of the two landslide susceptibility maps through (1) an evaluation with the location of mapped 'old' landslides and through (2) a temporal validation with spatial data of 'recent' (1960-1999; n = 48) and 'very recent' (2000-2008; n = 46) landslides showed a better prediction capacity for the statistical model produced in this study compared to the heuristic model. In total, the statistically-derived landslide susceptibility map succeeded in correctly classifying 81.0% of the 'old' and 91.6% of the 'recent' and 'very recent' landslides. On the susceptibility map

  7. REACTOR

    DOEpatents

    Roman, W.G.

    1961-06-27

    A pressurized water reactor in which automatic control is achieved by varying the average density of the liquid moderator-cooiant is patented. Density is controlled by the temperature and power level of the reactor ftself. This control can be effected by the use of either plate, pellet, or tubular fuel elements. The fuel elements are disposed between upper and lower coolant plenum chambers and are designed to permit unrestricted coolant flow. The control chamber has an inlet opening communicating with the lower coolant plenum chamber and a restricted vapor vent communicating with the upper coolant plenum chamber. Thus, a variation in temperature of the fuel elements will cause a variation in the average moderator density in the chamber which directly affects the power level of the reactor.

  8. REACTORS

    DOEpatents

    Spitzer, L. Jr.

    1961-10-01

    Thermonuclear reactors, methods, and apparatus are described for controlling and confining high temperature plasma. Main axial confining coils in combination with helical windings provide a rotational transform that avoids the necessity of a figure-eight shaped reactor tube. The helical windings provide a multipolar helical magnetic field transverse to the axis of the main axial confining coils so as to improve the effectiveness of the confining field by counteracting the tendency of the more central lines of force in the stellarator tube to exchange positions with the magnetic lines of force nearer the walls of the tube. (AEC)

  9. Reactor

    DOEpatents

    Evans, Robert M.

    1976-10-05

    1. A neutronic reactor having a moderator, coolant tubes traversing the moderator from an inlet end to an outlet end, bodies of material fissionable by neutrons of thermal energy disposed within the coolant tubes, and means for circulating water through said coolant tubes characterized by the improved construction wherein the coolant tubes are constructed of aluminum having an outer diameter of 1.729 inches and a wall thickness of 0.059 inch, and the means for circulating a liquid coolant through the tubes includes a source of water at a pressure of approximately 350 pounds per square inch connected to the inlet end of the tubes, and said construction including a pressure reducing orifice disposed at the inlet ends of the tubes reducing the pressure of the water by approximately 150 pounds per square inch.

  10. Mixed brittle-plastic deformation behaviour in a slate belt. Examples from the High-Ardenne slate belt (Belgium, Germany)

    NASA Astrophysics Data System (ADS)

    Sintubin, Manuel; van Baelen, Hervé; van Noten, Koen; Muchez, Philippe

    2010-05-01

    In the High-Ardenne slate belt, part of the Rhenohercynian external fold-and-thrust belt at the northern extremity of the Late Palaeozoic Variscan orogen (Belgium, Germany, France), particular quartz vein occurrences can be observed in predominantly fine-grained siliciclastic metasediments. Detailed structural, petrographical and geochemical studies has revealed that these vein occurrences can be related to a mixed brittle-plastic deformation behaviour in a low-grade metamorphic mid-crustal environment. The first type of quartz veins are bedding-perpendicular, lens-shaped extension veins that are confined to the sandstone layers within the multilayer sequence. Fluid inclusion studies demonstrate high fluid pressures suggesting that the individual sandstone bodies acted as isolated high-pressure compartments in an overpressured basin. Hydraulic fracturing occurred during the tectonic inversion (from extension to compression) in the earliest stages of the Variscan orogeny. The vein fill shows a blocky character indicating crystal growth in open cavities. Both the typical lens shape of the veins and the subsequent cuspate-lobate folding of the bed interfaces in between the quartz veins suggest plastic deformation of cohesionless fluid-filled fissures. Metamorphic grade of the host rock and fluid temperature and pressure clearly indicates mid-crustal conditions below the brittle-plastic transition. This first type of quartz veins exemplifies mixed brittle-plastic deformation behaviour, possibly related to a transient deepening of the brittle-plastic transition. This is in contrast with contemporaneous bedding-perpendicular crack-seal veins observed in higher - upper-crustal - structural levels in the slate belt, reflecting pure brittle deformation behaviour. The second type are discordant quartz veins confined to extensional low-angle detachment shear zones. These very irregular veins transect a pre-existing pervasive cleavage fabric. They show no matching walls and

  11. Shape and amount of the Quaternary uplift of the western Rhenish shield and the Ardennes (western Europe)

    NASA Astrophysics Data System (ADS)

    Demoulin, A.; Hallot, E.

    2009-09-01

    A good evaluation of the Quaternary uplift of the Rhenish shield is a key element for the understanding of the Cenozoic geodynamics of the western European platform in front of the alpine arc. Previous maps of the massif uplift relied on fluvial incision data since the time of the rivers' Younger Main Terrace to infer a maximum post-0.73 Ma uplift of ~ 290 m in the SE Eifel. Here, we propose a new interpretation of the incision data of the intra-massif streams, where anomalies in the terrace profiles would result from knickpoint retreat in the tributaries of the main rivers rather than from tectonic deformation. We also use additional geomorphological data referring to (1) deformed Tertiary planation surfaces, (2) the history of stream piracy that severely affected the Meuse basin in the last 1 Ma, and (3) incision data outside the Rhenish shield. A new map of the post-0.73 Ma uplift of the Rhenish shield is drawn on the basis of this enlarged dataset. It reduces the maximum amount of tectonic uplift in the SE Eifel to ~ 140 m and modifies the general shape of the uplift, namely straightening its E-W profile. It is also suggested that an uplift wave migrated across the massif, starting from its southern margin in the early Pleistocene and currently showing the highest intensity of uplift in the northern Ardennes and Eifel. These features seem to favour an uplift mechanism chiefly related to lithospheric folding and minimize the impact on the topography of a more local Eifel plume.

  12. The structure, stability, and infrared spectrum of B 2N, B 2N +, B 2N -, BO, B 2O and B 2N 2.

    NASA Astrophysics Data System (ADS)

    Martin, J. M. L.; François, J. P.; Gijbels, R.

    1992-05-01

    The structure, infrared spectrum, and heat of formation of B 2N, B 2N -, BO, and B 2O have been studied ab initio. B 2N is very stable; B 2O even more so. B 2N, B 2N -, B 2O, and probably B 2N + have symmetric linear ground-state structures; for B 2O, an asymmetric linear structure lies about 12 kcal/mol above the ground state. B 2N +, B 2N - and B 2O have intense asymmetric stretching frequencies, predicted near 870, 1590 and 1400 cm -1, respectively. Our predicted harmonic frequencies and isotopic shifts for B 2O confirm the recent experimental identification by Andrews and Burkholder. Absorptions at 1889.5 and 1998.5 cm -1 in noble-gas trapped boron nitride vapor belong the BNB and BNBN ( 3Π), respectively; a tentative assignment of 882.5 cm -1 to BNB + is proposed. Total atomization energies Σ De (Σ D0) are computed (accuracy ±2 kcal/mol) as: BO 193.1 (190.4), B 2O 292.5 (288.7), B 2N 225.0 (250.3) kcal/mol. The ionization potential and electron affinity of B 2N are predicted to be 8.62±0.1 and 3.34±0.1 eV. The MP4-level additivity approximations involved in G1 theory results in errors on the order of 1 kcal/mol in the Σ De values.

  13. Assessing the Economic Cost of Landslide Damage in Low-Relief Regions: Case Study Evidence from the Flemish Ardennes (Belgium)

    NASA Astrophysics Data System (ADS)

    Vranken, L.; Van Turnhout, P.; Van Den Eeckhaut, M.; Vandekerckhove, L.; Vantilt, G.; Poesen, J.

    2012-04-01

    Several regions around the globe are at risk to incur damage from landslides. These landslides cause significant structural and functional damage to public and private buildings and infrastructure. Numerous studies investigated how natural factors and human activities control the (re-)activation of landslides. However, few studies have concentrated on a quantitative estimate of the overall damage caused by landslides at a regional scale. This study therefore starts with a quantitative economic assessment of the direct and indirect damage caused by landslides in the Flemish Ardennes (Belgium), a low-relief region (area=ca. 700 km2) susceptible to landslides. Based on focus interviews as well as on semi-structured interviews with homeowners, civil servants (e.g. from the technical services from the various towns), or with the owners and providers of lifelines such as electricity and sewage, we have quantitatively estimated the direct and indirect damage induced by landsliding and this for a 10 to 30 year period (depending on the type of infrastructure or buildings). Economic damage to public infrastructure and buildings was estimated for the entire region, while for private damage 10 cases with severe to small damage were quantified. For example, in the last 10 year, costs of road repair augmented to 814 560 €. Costs to repair damaged roads that have not yet been repaired, were estimated at 669 318 €. In the past 30 years, costs of measures to prevent road damage augmented to at least 14 872 380 €. More than 90% of this budget for preventive measures was spent 30 years ago, when an important freeway was damaged and had to be repaired. These preventive measures (building a grout wall and improving the drainage system) were effective as no further damage has been reported until present. To repair and prevent damage to waterworks and sewage systems, expenditures amounted to 551 044 € and this for the last 30 years. In the past 10 years, a new railway line

  14. The Vaporization of B2O3(l) to B2O3(g) and B2O2(g)

    NASA Technical Reports Server (NTRS)

    Jacobson, Nathan S.; Myers, Dwight L.

    2011-01-01

    The vaporization of B2O3 in a reducing environment leads to formation of both B2O3(g) and B2O2(g). While formation of B2O3(g) is well understood, many questions about the formation of B2O2(g) remain. Previous studies using B(s) + B2O3(l) have led to inconsistent thermodynamic data. In this study, it was found that after heating, B(s) and B2O3(l) appear to separate and variations in contact area likely led to the inconsistent vapor pressures of B2O2(g). To circumvent this problem, an activity of boron is fixed with a two-phase mixture of FeB and Fe2B. Both second and third law enthalpies of formation were measured for B2O2(g) and B2O3(g). From these the enthalpies of formation at 298.15 K are calculated to be -479.9 +/- 41.5 kJ/mol for B2O2(g) and -833.4 +/- 13.1 kJ/mol for B2O3(g). Ab initio calculations to determine the enthalpies of formation of B2O2(g) and B2O3(g) were conducted using the W1BD composite method and show good agreement with the experimental values.

  15. Chooz A, First Pressurized Water Reactor to be Dismantled in France - 13445

    SciTech Connect

    Boucau, Joseph; Mirabella, C.; Nilsson, Lennart; Kreitman, Paul J.; Obert, Estelle

    2013-07-01

    Nine commercial nuclear power plants have been permanently shut down in France to date, of which the Chooz A plant underwent an extensive decommissioning and dismantling program. Chooz Nuclear Power Station is located in the municipality of Chooz, Ardennes region, in the northeast part of France. Chooz B1 and B2 are 1,500 megawatt electric (MWe) pressurized water reactors (PWRs) currently in operation. Chooz A, a 305 MWe PWR implanted in two caves within a hill, began operations in 1967 and closed in 1991, and will now become the first PWR in France to be fully dismantled. EDF CIDEN (Engineering Center for Dismantling and Environment) has awarded Westinghouse a contract for the dismantling of its Chooz A reactor vessel (RV). The project began in January 2010. Westinghouse is leading the project in a consortium with Nuvia France. The project scope includes overall project management, conditioning of the reactor vessel (RV) head, RV and RV internals segmentation, reactor nozzle cutting for lifting the RV out of the pit and seal it afterwards, dismantling of the RV thermal insulation, ALARA (As Low As Reasonably Achievable) forecast to ensure acceptable doses for the personnel, complementary vacuum cleaner to catch the chips during the segmentation work, needs and facilities, waste characterization and packaging, civil work modifications, licensing documentation. The RV and RV internals will be segmented based on the mechanical cutting technology that Westinghouse applied successfully for more than 13 years. The segmentation activities cover the cutting and packaging plan, tooling design and qualification, personnel training and site implementation. Since Chooz A is located inside two caves, the project will involve waste transportation from the reactor cave through long galleries to the waste buffer area. The project will end after the entire dismantling work is completed, and the waste storage is outside the caves and ready to be shipped either to the ANDRA (French

  16. Contribution of piezometric measurement to knowledge and management of low water levels: examples on the chalk aquifer in the Champagne Ardennes region

    NASA Astrophysics Data System (ADS)

    Stollsteiner, P.; Bessiere, H.; Nicolas, J.; Allier, D.; Berthet, O.

    2015-04-01

    This article is based on a BRGM study on piezometric indicators, threshold values of discharge and groundwater levels for the assessment of potentially-exploitable water resources of chalky watersheds. A method for estimating low water levels based on groundwater levels is presented from three examples representing chalk aquifers with different cycles: annual, combined and interannual. The first is located in Picardy and the two others in the Champagne-Ardennes region. Piezometers with annual cycles, used in these examples, are supposed to be representative of the aquifer hydro-dynamics. Except for multi-annual systems, the analysis between discharge measurements at a hydrometric station and groundwater levels measured at a piezometer representative of the main aquifer, leads to relatively precise and satisfactory relationships within a chalky context. These relationships may be useful for monitoring, validation, extension or reconstruction of the low water flow data. On the one hand, they allow definition of the piezometric levels corresponding to the different alert thresholds of river discharges. On the other hand, they clarify the proportions of low surface water flow from runoff or drainage of the aquifer. Finally, these correlations give an assessment of the minimum flow for the coming weeks. However, these correlations cannot be used to optimize the value of the exploitable water resource because it seems to be difficult to integrate the value of the effective rainfall that could occur during the draining period. Moreover, in the case of multi-annual systems, the solution is to attempt a comprehensive system modelling and, if it is satisfactory, using the simulated values to get rid of parasites or running the model for forecasting purposes.

  17. 18 CFR 1b.2 - Scope.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Scope. 1b.2 Section 1b.2 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.2 Scope. This part applies to...

  18. 18 CFR 1b.2 - Scope.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Scope. 1b.2 Section 1b.2 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.2 Scope. This part applies to...

  19. 42 CFR 52b.2 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Definitions. 52b.2 Section 52b.2 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.2 Definitions. As used in this part: Act means the Public Health Service Act,...

  20. 42 CFR 52b.2 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Definitions. 52b.2 Section 52b.2 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.2 Definitions. As used in this part: Act means the Public Health Service Act,...

  1. 42 CFR 52b.2 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Definitions. 52b.2 Section 52b.2 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.2 Definitions. As used in this part: Act means the Public Health Service Act,...

  2. 42 CFR 52b.2 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Definitions. 52b.2 Section 52b.2 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.2 Definitions. As used in this part: Act means the Public Health Service Act,...

  3. 42 CFR 52b.2 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Definitions. 52b.2 Section 52b.2 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.2 Definitions. As used in this part: Act means the Public Health Service Act,...

  4. 7 CFR 1b.2 - Policy.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 1 2013-01-01 2013-01-01 false Policy. 1b.2 Section 1b.2 Agriculture Office of the Secretary of Agriculture NATIONAL ENVIRONMENTAL POLICY ACT § 1b.2 Policy. (a) All policies and programs of... compliance with Executive Order 12114, “Environmental Effects Abroad of Major Federal Actions.”...

  5. 18 CFR 1b.2 - Scope.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Scope. 1b.2 Section 1b.2 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.2 Scope. This part applies to...

  6. 18 CFR 1b.2 - Scope.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Scope. 1b.2 Section 1b.2 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.2 Scope. This part applies to...

  7. 18 CFR 1b.2 - Scope.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Scope. 1b.2 Section 1b.2 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.2 Scope. This part applies to...

  8. 12 CFR 264b.2 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 3 2011-01-01 2011-01-01 false Definitions. 264b.2 Section 264b.2 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM RULES... dependents (within the meaning of section 152 of the Internal Revenue Code of 1986 (26 U.S.C. 152)) of...

  9. 38 CFR 18b.2 - Reviewing authority.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) PRACTICE AND PROCEDURE UNDER TITLE VI OF THE CIVIL RIGHTS ACT OF 1964 AND PART 18 OF THIS CHAPTER General Rules § 18b.2 Reviewing authority. The term reviewing authority means the Secretary of Veterans...

  10. B2M — EDRN Public Portal

    Cancer.gov

    B2M, a secreted protein belonging to the beta-2-microglobulin family, is a component of the class I major histocompatibility complex (MHC) on the surface of nearly all nucleated cells and involved in the presentation of peptide antigens to the immune system. A mutation in this gene has been shown to result in hypercatabolic hypoproteinemia. B2M is detected in serum and urine.

  11. Doping-induced superconductivity of ZrB2 and HfB2

    NASA Astrophysics Data System (ADS)

    Barbero, N.; Shiroka, T.; Delley, B.; Grant, T.; Machado, A. Â. J. Â. S.; Fisk, Z.; Ott, H.-R.; Mesot, J.

    2017-03-01

    Unlike the widely studied s -type two-gap superconductor MgB2, the chemically similar compounds ZrB2 and HfB2 do not superconduct above 1 K. Yet it has been shown that small amounts of self or extrinsic doping (in particular with vanadium), can induce superconductivity in these materials. Based on results of different macroscopic and microscopic measurements, including magnetometry, nuclear magnetic resonance (NMR), resistivity, and muon-spin rotation (μ+SR ), we present a comparative study of Zr0.96V0.04B2 and Hf0.97V0.03B2 . Their key magnetic and superconducting features are determined and the results are considered within the theoretical framework of multiband superconductivity proposed for MgB2. Detailed Fermi surface (FS) and electronic structure calculations reveal the difference between MgB2 and transition-metal diborides.

  12. Superconductivity in MgB 2

    NASA Astrophysics Data System (ADS)

    Akimitsu, Jun; Muranaka, Takahiro

    2003-05-01

    We recently discovered that the intermetallic compound magnesium diboride (MgB2) exhibits the highest superconducting transition temperature (Tc=39 K) of all the metallic superconductors. In this paper we report on the basic superconducting characteristics of MgB2 and the current status of the research for the unanswered problem in this superconductivity. Especially, we review the several reports for the superconducting gap (Δ) by the spectroscopic measurements. Moreover we introduce the research into its anisotropic parameter (γ), which is important for the understanding of this superconducting states in this material.

  13. Fast Reactors

    NASA Astrophysics Data System (ADS)

    Esposito, S.; Pisanti, O.

    The following sections are included: * Elementary Considerations * The Integral Equation to the Neutron Distribution * The Critical Size for a Fast Reactor * Supercritical Reactors * Problems and Exercises

  14. Infrared and Ultraviolet Spectra of Diborane(6): B2H6 and B2D6.

    PubMed

    Peng, Yu-Chain; Chou, Sheng-Lung; Lo, Jen-Iu; Lin, Meng-Yeh; Lu, Hsiao-Chi; Cheng, Bing-Ming; Ogilvie, J F

    2016-07-21

    We recorded absorption spectra of diborane(6), B2H6 and B2D6, dispersed in solid neon near 4 K in both mid-infrared and ultraviolet regions. For gaseous B2H6 from 105 to 300 nm, we report quantitative absolute cross sections; for solid B2H6 and for B2H6 dispersed in solid neon, we measured ultraviolet absorbance with relative intensities over a wide range. To assign the mid-infrared spectra to specific isotopic variants, we applied the abundance of (11)B and (10)B in natural proportions; we undertook quantum-chemical calculations of wavenumbers associated with anharmonic vibrational modes and the intensities of the harmonic vibrational modes. To aid an interpretation of the ultraviolet spectra, we calculated the energies of electronically excited singlet and triplet states and oscillator strengths for electronic transitions from the electronic ground state.

  15. CARDIO-i2b2: integrating arrhythmogenic disease data in i2b2.

    PubMed

    Segagni, Daniele; Tibollo, Valentina; Dagliati, Arianna; Napolitano, Carlo; G Priori, Silvia; Bellazzi, Riccardo

    2012-01-01

    The CARDIO-i2b2 project is an initiative to customize the i2b2 bioinformatics tool with the aim to integrate clinical and research data in order to support translational research in cardiology. In this work we describe the implementation and the customization of i2b2 to manage the data of arrhytmogenic disease patients collected at the Fondazione Salvatore Maugeri of Pavia in a joint project with the NYU Langone Medical Center (New York, USA). The i2b2 clinical research chart data warehouse is populated with the data obtained by the research database called TRIAD. The research infrastructure is extended by the development of new plug-ins for the i2b2 web client application able to properly select and export phenotypic data and to perform data analysis.

  16. A Review of Gas-Cooled Reactor Concepts for SDI Applications

    DTIC Science & Technology

    1989-08-01

    Reactor B-2 B.2 NERVA Derivative Reactor B-2 B.3 Pellet-Bed Reactor B-5 B.4 PLUTO Derivative Reactor B-7 B.5 NERVA/ PLUTO Hybrid Reactor...Method °-2 D. 2 Burst-Mode Mass Estimates D-3 D.2.1 Pellet-Bed Reactor D-3 D.2.2 PLUTO Derivative Reactor D-3 D.2.3 NERVA/ PLUTO Hybrid Reactor...Reactor D-5 D.2.9 Foam-Fuel Reactor D-5 D. 3 MMWSS-Mode Mass Estimates D-6 D. 3 .1 Pellet Bed Reactor D-6 D.3.2 PLUTO Derivative D-6 D.3.3

  17. NEUTRONIC REACTOR

    DOEpatents

    Fermi, E.; Zinn, W.H.; Anderson, H.L.

    1958-09-16

    Means are presenied for increasing the reproduction ratio of a gaphite- moderated neutronic reactor by diminishing the neutron loss due to absorption or capture by gaseous impurities within the reactor. This means comprised of a fluid-tight casing or envelope completely enclosing the reactor and provided with a valve through which the casing, and thereby the reactor, may be evacuated of atmospheric air.

  18. B11 NMR in the layered diborides OsB2 and RuB2

    NASA Astrophysics Data System (ADS)

    Suh, B. J.; Zong, X.; Singh, Y.; Niazi, A.; Johnston, D. C.

    2007-10-01

    B11 nuclear magnetic resonance (NMR) measurements have been performed on B11 enriched OsB2 and RuB2 polycrystalline powder samples in an external field of 4.7T and in the temperature range, 4.2KB2 and RuB2 , respectively. The experimental results indicate that a p character dominates the conduction electron wave function at the B site with a negligibly small s character in both compounds.

  19. Lattice Thermal Conductivity from Atomistic Simulations: ZrB2 and HfB2

    NASA Technical Reports Server (NTRS)

    Lawson, John W.; Daw, Murray S.; Bauschlicher, Charles W.

    2012-01-01

    Ultra high temperature ceramics (UHTC) including ZrB2 and HfB2 have a number of properties that make them attractive for applications in extreme environments. One such property is their high thermal conductivity. Computational modeling of these materials will facilitate understanding of fundamental mechanisms, elucidate structure-property relationships, and ultimately accelerate the materials design cycle. Progress in computational modeling of UHTCs however has been limited in part due to the absence of suitable interatomic potentials. Recently, we developed Tersoff style parameterizations of such potentials for both ZrB2 and HfB2 appropriate for atomistic simulations. As an application, Green-Kubo molecular dynamics simulations were performed to evaluate the lattice thermal conductivity for single crystals of ZrB2 and HfB2. The atomic mass difference in these binary compounds leads to oscillations in the time correlation function of the heat current, in contrast to the more typical monotonic decay seen in monoatomic materials such as Silicon, for example. Results at room temperature and at elevated temperatures will be reported.

  20. On the electron affinity of B2

    SciTech Connect

    Glezakou, Vanda A.; Taylor, Peter

    2009-02-02

    We present the results of high-level ab initio calculations on the electron affinity of B2. Our new best estimate of 1.93±0.03 eV is in agreement with previous calculations as well as the sole existing experimental estimate of 1.8 eV, as derived from quantities with an uncertainty of 0.4 eV. The electron affinity of atomic boron, which is much smaller, is also calculated for comparison, and again found to be in good agreement with experiment. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

  1. A monoclonal antibody targeting ErbB2 domain III inhibits ErbB2 signaling and suppresses the growth of ErbB2-overexpressing breast tumors

    PubMed Central

    Meng, Y; Zheng, L; Yang, Y; Wang, H; Dong, J; Wang, C; Zhang, Y; Yu, X; Wang, L; Xia, T; Zhang, D; Guo, Y; Li, B

    2016-01-01

    The anti-ErbB2 antibodies trastuzumab and pertuzumab in combination have recently been approved for the treatment of patients with ErbB2-positive metastatic breast cancer. Pertuzumab, which binds to ErbB2 near the center of domain II, and trastuzumab, which binds to the juxtamembrane region of ErbB2 domain IV, directly interfere with domain II- and domain IV-mediated heterodimerization contacts, respectively. In this study, we report a novel anti-ErbB2 antibody, 3E10, which binds to an epitope in domain III that appears to be located opposite to the dimerization interfaces in domain II and domain IV of ErbB2. Our data show that the 3E10 antibody inhibits ErbB2 heterodimerization via a mechanism that strikingly differs from trastuzumab and pertuzumab. It could be speculated that the 3E10 antibody may affect ErbB2 heterodimerization by causing major conformational changes of ErbB2. Furthermore, 3E10 provides synergistic inhibition of ErbB2 heterodimerization and signaling in combination with either trastuzumab or pertuzumab. The combination of these three anti-ErbB2 antibodies that have complementary mechanisms of action appears to be an extremely potent ErbB2 heterodimerization blocker. Compared with trastuzumab plus pertuzumab, the combination of trastuzumab, pertuzumab and 3E10 provides a more potent blockade of ErbB2 signaling. Consistent with this, trastuzumab plus pertuzumab plus 3E10 results in greater in vitro and in vivo antitumor activity in ErbB2-overexpressing breast tumor models, suggesting its potential use for treating ErbB2-overexpressing breast cancer. PMID:26999718

  2. A monoclonal antibody targeting ErbB2 domain III inhibits ErbB2 signaling and suppresses the growth of ErbB2-overexpressing breast tumors.

    PubMed

    Meng, Y; Zheng, L; Yang, Y; Wang, H; Dong, J; Wang, C; Zhang, Y; Yu, X; Wang, L; Xia, T; Zhang, D; Guo, Y; Li, B

    2016-03-21

    The anti-ErbB2 antibodies trastuzumab and pertuzumab in combination have recently been approved for the treatment of patients with ErbB2-positive metastatic breast cancer. Pertuzumab, which binds to ErbB2 near the center of domain II, and trastuzumab, which binds to the juxtamembrane region of ErbB2 domain IV, directly interfere with domain II- and domain IV-mediated heterodimerization contacts, respectively. In this study, we report a novel anti-ErbB2 antibody, 3E10, which binds to an epitope in domain III that appears to be located opposite to the dimerization interfaces in domain II and domain IV of ErbB2. Our data show that the 3E10 antibody inhibits ErbB2 heterodimerization via a mechanism that strikingly differs from trastuzumab and pertuzumab. It could be speculated that the 3E10 antibody may affect ErbB2 heterodimerization by causing major conformational changes of ErbB2. Furthermore, 3E10 provides synergistic inhibition of ErbB2 heterodimerization and signaling in combination with either trastuzumab or pertuzumab. The combination of these three anti-ErbB2 antibodies that have complementary mechanisms of action appears to be an extremely potent ErbB2 heterodimerization blocker. Compared with trastuzumab plus pertuzumab, the combination of trastuzumab, pertuzumab and 3E10 provides a more potent blockade of ErbB2 signaling. Consistent with this, trastuzumab plus pertuzumab plus 3E10 results in greater in vitro and in vivo antitumor activity in ErbB2-overexpressing breast tumor models, suggesting its potential use for treating ErbB2-overexpressing breast cancer.

  3. Direct inhibition of cell surface ephrin-B2 by recombinant ephrin-B2/FC.

    PubMed

    Xiaodong, Hu; Zhen, Huang; Min, Sun; Zhiming, Cui; Hongyan, Ji; Chong, Zhang; Xuefeng, Tan; Guohua, Jin

    2013-10-18

    First messengers and viral transfection are the two most common ways to stimulate cells for signal output, although their applications are limited. We investigated mechanisms of inducing neural stem cell differentiation using recombinant ephrin-B2/Fc and found that it acted as a ligand and inhibited endogenous ephrin-B2, which maintenance of the neural progenitor cell state, by direct interference. Our results showed the movement of ephrin-B2/Fc within the cell and indicated that it recycled to the plasma membrane surface, revealing a possible pattern of ephrin trafficking. Our results also serve as proof of concept for the reconstruction of the intracellular domain of ephrin using an artificial receptor to direct input signals in future studies.

  4. Producing composite materials based on ZrB2, ZrB2-SiC

    NASA Astrophysics Data System (ADS)

    Mirovoi, Yu A.; Burlachenko, A. G.; Buyakova, S. P.; Sevostiyanova, I. N.; Kulkov, S. N.

    2016-11-01

    The effect of mechanical treatment by planetary ball milling on the properties of hot pressed ZrB2 - SiC ceramics was studied. It has been shown that material densification after mechanical treatment is finished at initial stages of sintering process. Addition of SiC causes a substantial increase in density of the sample to 99% of the theoretical powder containing 20% of silicon carbide, in comparison with samples ZrB2 density not exceeding 76%. It has been shown that all defects which were accumulated during mechanical treatment anneal in hot pressure process and there are no any changes of CDD values in sintered ceramics.

  5. BOILING REACTORS

    DOEpatents

    Untermyer, S.

    1962-04-10

    A boiling reactor having a reactivity which is reduced by an increase in the volume of vaporized coolant therein is described. In this system unvaporized liquid coolant is extracted from the reactor, heat is extracted therefrom, and it is returned to the reactor as sub-cooled liquid coolant. This reduces a portion of the coolant which includes vaporized coolant within the core assembly thereby enhancing the power output of the assembly and rendering the reactor substantially self-regulating. (AEC)

  6. NEUTRONIC REACTOR

    DOEpatents

    Daniels, F.

    1959-10-27

    A reactor in which at least a portion of the moderator is in the form of movable refractory balls is described. In addition to their moderating capacity, these balls may serve as carriers for fissionable material or fertile material, or may serve in a coolant capacity to remove heat from the reactor. A pneumatic system is used to circulate the balls through the reactor.

  7. NUCLEAR REACTOR

    DOEpatents

    Treshow, M.

    1961-09-01

    A boiling-water nuclear reactor is described wherein control is effected by varying the moderator-to-fuel ratio in the reactor core. This is accomplished by providing control tubes containing a liquid control moderator in the reactor core and providing means for varying the amount of control moderatcr within the control tubes.

  8. CONVECTION REACTOR

    DOEpatents

    Hammond, R.P.; King, L.D.P.

    1960-03-22

    An homogeneous nuclear power reactor utilizing convection circulation of the liquid fuel is proposed. The reactor has an internal heat exchanger looated in the same pressure vessel as the critical assembly, thereby eliminating necessity for handling the hot liquid fuel outside the reactor pressure vessel during normal operation. The liquid fuel used in this reactor eliminates the necessity for extensive radiolytic gas rocombination apparatus, and the reactor is resiliently pressurized and, without any movable mechanical apparatus, automatically regulates itself to the condition of criticality during moderate variations in temperature snd pressure and shuts itself down as the pressure exceeds a predetermined safe operating value.

  9. Research reactors

    SciTech Connect

    Tonneson, L.C.; Fox, G.J.

    1996-04-01

    There are currently 284 research reactors in operation, and 12 under construction around the world. Of the operating reactors, nearly two-thirds are used exclusively for research, and the rest for a variety of purposes, including training, testing, and critical assembly. For more than 50 years, research reactor programs have contributed greatly to the scientific and educational communities. Today, six of the world`s research reactors are being shut down, three of which are in the USA. With government budget constraints and the growing proliferation concerns surrounding the use of highly enriched uranium in some of these reactors, the future of nuclear research could be impacted.

  10. Decomposition of the B2-type matrix

    NASA Astrophysics Data System (ADS)

    Gale, W. F.; King, J. E.

    1992-09-01

    The microstructural stability of aluminide diffusion coatings, prepared by means of a two-stage pack-aluminization treatment on single-crystal nickel-base superalloy substrates, is considered in this article. Edge-on specimens of coated superalloy are studied using transmission electron microscopy (TEM). The effects of coating thickness and post-coating heat treatment (duration, temperature, and atmosphere) on coating microstructure are examined. The article discusses the partial transformation of the matrix of the coating, from a B2-type phase (nominally NiAl) to a L12 phase (nominally Ni3(Al, Ti)), during exposure at temperatures of 850 °C and 950 °C in air and in vacuum for up to 138 hours. Three possible processes that can account for decom- position of the coating matrix are investigated, namely, interdiffusion between the coating and the substrate, oxidation of the coating surface, and aging of the coating. Of these processes, aging of the coating is shown to be the predominant factor in the coating transformation under the conditions considered.

  11. Improved Superconducting properties in the Mg(11)B2 low activation superconductor prepared by low-temperature sintering.

    PubMed

    Cheng, Fang; Liu, Yongchang; Ma, Zongqing; Shahriar Al Hossain, M; Somer, M

    2016-05-05

    Mg(11)B2 has a great application prospect in the superconducting coils for fusion reactor as the "low activation superconductors". The un-doped Mg(11)B2 and Cu-doped Mg(11)B2 bulks using (11)B as a boron precursor were fabricated by low-temperature sintering in present work. It was found that the prepared Mg(11)B2 low activation superconductors exhibit better Jc performance than all of other Mg(11)B2 samples reported in previous studies. As for Cu doped Mg(11)B2, minor Cu addition can obviously improve the Mg(11)B2 grain crystallization and reduce the amount of MgO impurity. Hence, improved grain connectivity and higher Jc at low fields is obtained in Cu doped Mg(11)B2 samples. For un-doped samples, refined grains and more MgO impurity with proper size brought about more flux pinning centers, resulting in better Jc performance at high fields.

  12. Improved Superconducting properties in the Mg11B2 low activation superconductor prepared by low-temperature sintering

    PubMed Central

    Cheng, Fang; Liu, Yongchang; Ma, Zongqing; Shahriar Al Hossain, M.; Somer, M.

    2016-01-01

    Mg11B2 has a great application prospect in the superconducting coils for fusion reactor as the “low activation superconductors”. The un-doped Mg11B2 and Cu-doped Mg11B2 bulks using 11B as a boron precursor were fabricated by low-temperature sintering in present work. It was found that the prepared Mg11B2 low activation superconductors exhibit better Jc performance than all of other Mg11B2 samples reported in previous studies. As for Cu doped Mg11B2, minor Cu addition can obviously improve the Mg11B2 grain crystallization and reduce the amount of MgO impurity. Hence, improved grain connectivity and higher Jc at low fields is obtained in Cu doped Mg11B2 samples. For un-doped samples, refined grains and more MgO impurity with proper size brought about more flux pinning centers, resulting in better Jc performance at high fields. PMID:27149682

  13. Characterization of MgB2 Conductors for Coil Development

    NASA Astrophysics Data System (ADS)

    Aslanoglu, Z.; Arda, L.; Akin, Y.; Sumption, M. D.; Tomsic, M.; Hascicek, Y. S.

    2004-06-01

    The effects of the heat treatment conditions on microstructure and the transport critical current density of MgB2 wires, which were fabricated by the Continuous Tube Forming and Filling (CTFF) process, have been investigated. Two types of MgB2 conductors, Fe/MgB2 and Cu/MgB2, were studied. It was found that the sheath materials affect the optimum annealing profile of MgB2 conductor. The annealing temperature for Cu/MgB2 conductors was lower than that for the Fe/MgB2 conductors. The critical current density, Jc was measured to be 1.1×105 A/cm2 at 20 K in-self field for Cu/MgB2 conductor of 1.25 mm in diameter. The processing, microstructure and superconducting properties are presented.

  14. B-2 Extremely High Frequency SATCOM and Computer Increment 1 (B-2 EHF Inc 1)

    DTIC Science & Technology

    2015-12-01

    provide upgraded flight management computer processors , increased data storage, a re-hosted Flight Management Operational Flight Program, and a high...bandwidth data bus in order to prevent degradation of existing capabilities resulting from EHF SATCOM installation. Additionally, the Increment 1...because the program is 90% or more expended and 90% or more delivered. B-2 EHF Inc 1 consists of upgraded flight management processors , increased

  15. Electronic Commerce in Tourism in China: B2B or B2C?

    NASA Astrophysics Data System (ADS)

    Li, Hongxiu; Suomi, Reima

    E-commerce has significantly changed the distribution channels of travel products in the world including China. Online channels are growing important in travel service distribution. In China tourism industry has been developed rapidly with the economic development, more and more international travel service providers are trying to expand their Chinese market through the Internet. This paper sheds lights on the e-commerce development models in China for international travel service providers. It explores the current e-tourism in China from the three different participants in the value chain in tourism industry - consumer, travel agent and travel service provider. The paper also identifies the barriers in B2C arena in international outbound travel market, and discusses the possible approaches for international travel service providers to develop their e-commerce in the huge Chinese market. The results in this study reveal that international travel service providers should focus on B2B model to expand their electronic market in China. B2C development in tourism largely depends on the change of Chinese customers' behavior and the change of international tourism regulations. The findings of the study are expected to assist international travel service providers to understand current e-tourism in China and to support their planning for future e-commerce development in China.

  16. 26 CFR 1.663(b)-2 - Election.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Election. 1.663(b)-2 Section 1.663(b)-2 Internal... TAXES Estates and Trusts Which May Accumulate Income Or Which Distribute Corpus § 1.663(b)-2 Election. (a) Manner and time of election; irrevocability—(1) When return is required to be filed. If a...

  17. 34 CFR 5b.2 - Purpose and scope.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 34 Education 1 2012-07-01 2012-07-01 false Purpose and scope. 5b.2 Section 5b.2 Education Office of the Secretary, Department of Education PRIVACY ACT REGULATIONS § 5b.2 Purpose and scope. (a) This part implements section 3 of the Privacy Act of 1974, 5 U.S.C. 552a (hereinafter referred to as the...

  18. NEUTRONIC REACTOR

    DOEpatents

    Fraas, A.P.; Mills, C.B.

    1961-11-21

    A neutronic reactor in which neutron moderation is achieved primarily in its reflector is described. The reactor structure consists of a cylindrical central "island" of moderator and a spherical moderating reflector spaced therefrom, thereby providing an annular space. An essentially unmoderated liquid fuel is continuously passed through the annular space and undergoes fission while contained therein. The reactor, because of its small size, is particularly adapted for propulsion uses, including the propulsion of aircraft. (AEC)

  19. REACTOR COOLING

    DOEpatents

    Quackenbush, C.F.

    1959-09-29

    A nuclear reactor with provisions for selectively cooling the fuel elements is described. The reactor has a plurality of tubes extending throughout. Cylindrical fuel elements are disposed within the tubes and the coolant flows through the tubes and around the fuel elements. The fuel elements within the central portion of the reactor are provided with roughened surfaces of material. The fuel elements in the end portions of the tubes within the reactor are provlded with low conduction jackets and the fuel elements in the region between the central portion and the end portions are provided with smooth surfaces of high heat conduction material.

  20. NEUTRONIC REACTOR

    DOEpatents

    Metcalf, H.E.; Johnson, H.W.

    1961-04-01

    BS>A nuclear reactor incorporating fuel rods passing through a moderator and including tubes of a material of higher Thermal conductivity than the fuel in contact with the fuel is described. The tubes extend beyond the active portion of the reactor into contant with a fiuld coolant.

  1. NEUTRONIC REACTOR

    DOEpatents

    Wigner, E.P.

    1958-04-22

    A nuclear reactor for isotope production is described. This reactor is designed to provide a maximum thermal neutron flux in a region adjacent to the periphery of the reactor rather than in the center of the reactor. The core of the reactor is generally centrally located with respect tn a surrounding first reflector, constructed of beryllium. The beryllium reflector is surrounded by a second reflector, constructed of graphite, which, in tune, is surrounded by a conventional thermal shield. Water is circulated through the core and the reflector and functions both as a moderator and a coolant. In order to produce a greatsr maximum thermal neutron flux adjacent to the periphery of the reactor rather than in the core, the reactor is designed so tbat the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the materials in the reflector is approximately twice the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the material of the core of the reactor.

  2. 49 CFR 178.33b-2 - Type and size.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Type and size. 178.33b-2 Section 178.33b-2... Specifications for Inside Containers, and Linings § 178.33b-2 Type and size. (a) Single-trip inside containers. (b) The maximum capacity of containers in this class shall not exceed one liter (61.0 cubic...

  3. 49 CFR 178.33b-2 - Type and size.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Type and size. 178.33b-2 Section 178.33b-2... Containers, and Linings § 178.33b-2 Type and size. (a) Single-trip inside containers. (b) The maximum capacity of containers in this class shall not exceed one liter (61.0 cubic inches). The maximum...

  4. B2B Models for DoD Acquisition

    DTIC Science & Technology

    2008-01-15

    public release; distribution is unlimited 12b. DISTRIBUTION CODE 13. ABSTRACT (Maximum 200 words.) A central vision of B2B e - commerce is that...OF ABSTRACT: UU - ii - THIS PAGE INTENTIONALLY LEFT BLANK - iii - Abstract A central vision of B2B e - commerce is that of...goods and services are purchased, pricing mechanisms, the characteristics of the markets, and ownership of marketplace. Keywords: B2B E - Commerce

  5. Nucleolin-binding by ErbB2 enhances tumorigenicity of ErbB2-positive breast cancer

    PubMed Central

    Wolfson, Eya; Goldenberg, Maria; Solomon, Shira; Frishberg, Amit; Pinkas-Kramarski, Ronit

    2016-01-01

    ErbB2 is an important member of the ErbB family, which activates growth and proliferation signaling pathways. ErbB2 is often overexpressed in various malignancies, especially in breast cancer, and is a common target for anti-cancer drugs. Breast cancer is currently one of the leading mortality causes in women, and acquired resistance to ErbB2-targeted therapies is a major obstacle in its treatment. Thus, understanding ErbB2-mediated signaling is crucial for further development of anti-cancer therapeutics and disease treatment. Previously, we have reported that the ErbB receptors interact with the major nucleolar protein nucleolin. In addition to its function in the nucleoli of cells, nucleolin participates in various cellular processes at the cytoplasm and cell-surface. Deregulated nucleolin is frequently overexpressed on the membrane of cancer cells. Here, we show that nucleolin increases colony formation and anchorage-independent growth of ErbB2-overexpressing cells. Importantly, this enhanced tumorigenicity also occurs in human ErbB2-positive breast cancer patients; namely, nucleolin overexpression in these patients is associated with reduced patient survival rates and increased disease-risk. ErbB2-nucleolin complexes are formed endogenously in both normal and cancer cells, and their effect on tumorigenicity is mediated through activation of ErbB2 signaling. Accordingly, nucleolin inhibition reduces cell viability and ErbB2 activation in ErbB2-positive cancer cells. PMID:27542246

  6. Compact Reactor

    SciTech Connect

    Williams, Pharis E.

    2007-01-30

    Weyl's Gauge Principle of 1929 has been used to establish Weyl's Quantum Principle (WQP) that requires that the Weyl scale factor should be unity. It has been shown that the WQP requires the following: quantum mechanics must be used to determine system states; the electrostatic potential must be non-singular and quantified; interactions between particles with different electric charges (i.e. electron and proton) do not obey Newton's Third Law at sub-nuclear separations, and nuclear particles may be much different than expected using the standard model. The above WQP requirements lead to a potential fusion reactor wherein deuterium nuclei are preferentially fused into helium nuclei. Because the deuterium nuclei are preferentially fused into helium nuclei at temperatures and energies lower than specified by the standard model there is no harmful radiation as a byproduct of this fusion process. Therefore, a reactor using this reaction does not need any shielding to contain such radiation. The energy released from each reaction and the absence of shielding makes the deuterium-plus-deuterium-to-helium (DDH) reactor very compact when compared to other reactors, both fission and fusion types. Moreover, the potential energy output per reactor weight and the absence of harmful radiation makes the DDH reactor an ideal candidate for space power. The logic is summarized by which the WQP requires the above conditions that make the prediction of DDH possible. The details of the DDH reaction will be presented along with the specifics of why the DDH reactor may be made to cause two deuterium nuclei to preferentially fuse to a helium nucleus. The presentation will also indicate the calculations needed to predict the reactor temperature as a function of fuel loading, reactor size, and desired output and will include the progress achieved to date.

  7. B2B Models for DoD Acquisition

    DTIC Science & Technology

    2007-07-30

    ar^qb=p`elli=lc=_rpfkbpp=C=mr_if`=mlif`v - i - k^s^i=mlpqdo^ar^qb=p`elli= Abstract A central vision of B2B e - commerce is that of an electronic...are purchased, pricing mechanisms, the characteristics of the markets, and ownership of marketplace. Keywords: B2B E - Commerce , Internet...interest is in the analysis, design and implementation of computer-based information systems. Specifically, he is interested in B2B and B2C e - commerce

  8. NUCLEAR REACTOR

    DOEpatents

    Moore, R.V.; Bowen, J.H.; Dent, K.H.

    1958-12-01

    A heterogeneous, natural uranium fueled, solid moderated, gas cooled reactor is described, in which the fuel elements are in the form of elongated rods and are dlsposed within vertical coolant channels ln the moderator symmetrically arranged as a regular lattice in groups. This reactor employs control rods which operate in vertical channels in the moderator so that each control rod is centered in one of the fuel element groups. The reactor is enclosed in a pressure vessel which ls provided with access holes at the top to facilitate loading and unloadlng of the fuel elements, control rods and control rod driving devices.

  9. NUCLEAR REACTOR

    DOEpatents

    Miller, H.I.; Smith, R.C.

    1958-01-21

    This patent relates to nuclear reactors of the type which use a liquid fuel, such as a solution of uranyl sulfate in ordinary water which acts as the moderator. The reactor is comprised of a spherical vessel having a diameter of about 12 inches substantially surrounded by a reflector of beryllium oxide. Conventionnl control rods and safety rods are operated in slots in the reflector outside the vessel to control the operation of the reactor. An additional means for increasing the safety factor of the reactor by raising the ratio of delayed neutrons to prompt neutrons, is provided and consists of a soluble sulfate salt of beryllium dissolved in the liquid fuel in the proper proportion to obtain the result desired.

  10. NEUTRONIC REACTOR

    DOEpatents

    Anderson, H.L.

    1960-09-20

    A nuclear reactor is described comprising fissionable material dispersed in graphite blocks, helium filling the voids of the blocks and the spaces therebetween, and means other than the helium in thermal conductive contact with the graphite for removing heat.

  11. NEUTRONIC REACTOR

    DOEpatents

    Hurwitz, H. Jr.; Brooks, H.; Mannal, C.; Payne, J.H.; Luebke, E.A.

    1959-03-24

    A reactor of the heterogeneous, liquid cooled type is described. This reactor is comprised of a central region of a plurality of vertically disposed elongated tubes surrounded by a region of moderator material. The central region is comprised of a central core surrounded by a reflector region which is surrounded by a fast neutron absorber region, which in turn is surrounded by a slow neutron absorber region. Liquid sodium is used as the primary coolant and circulates through the core which contains the fuel elements. Control of the reactor is accomplished by varying the ability of the reflector region to reflect neutrons back into the core of the reactor. For this purpose the reflector is comprised of moderator and control elements having varying effects on reactivity, the control elements being arranged and actuated by groups to give regulation, shim, and safety control.

  12. NEUTRONIC REACTOR

    DOEpatents

    Fermi, E.

    1960-04-01

    A nuclear reactor is described consisting of blocks of graphite arranged in layers, natural uranium bodies disposed in holes in alternate layers of graphite blocks, and coolant tubes disposed in the layers of graphite blocks which do not contain uranium.

  13. NEUTRONIC REACTORS

    DOEpatents

    Wigner, E.P.

    1960-11-22

    A nuclear reactor is described wherein horizontal rods of thermal- neutron-fissionable material are disposed in a body of heavy water and extend through and are supported by spaced parallel walls of graphite.

  14. REACTOR SHIELD

    DOEpatents

    Wigner, E.P.; Ohlinger, L.E.; Young, G.J.; Weinberg, A.M.

    1959-02-17

    Radiation shield construction is described for a nuclear reactor. The shield is comprised of a plurality of steel plates arranged in parallel spaced relationship within a peripheral shell. Reactor coolant inlet tubes extend at right angles through the plates and baffles are arranged between the plates at right angles thereto and extend between the tubes to create a series of zigzag channels between the plates for the circulation of coolant fluid through the shield. The shield may be divided into two main sections; an inner section adjacent the reactor container and an outer section spaced therefrom. Coolant through the first section may be circulated at a faster rate than coolant circulated through the outer section since the area closest to the reactor container is at a higher temperature and is more radioactive. The two sections may have separate cooling systems to prevent the coolant in the outer section from mixing with the more contaminated coolant in the inner section.

  15. NUCLEAR REACTOR

    DOEpatents

    Sherman, J.; Sharbaugh, J.E.; Fauth, W.L. Jr.; Palladino, N.J.; DeHuff, P.G.

    1962-10-23

    A nuclear reactor incorporating seed and blanket assemblies is designed. Means are provided for obtaining samples of the coolant from the blanket assemblies and for varying the flow of coolant through the blanket assemblies. (AEC)

  16. NUCLEAR REACTOR

    DOEpatents

    Breden, C.R.; Dietrich, J.R.

    1961-06-20

    A water-soluble non-volatile poison may be introduced into a reactor to nullify excess reactivity. The poison is removed by passing a side stream of the water containing the soluble poison to an evaporation chamber. The vapor phase is returned to the reactor to decrease the concentration of soluble poison and the liquid phase is returned to increase the concentration of soluble poison.

  17. NEUTRONIC REACTORS

    DOEpatents

    Vernon, H.C.

    1959-01-13

    A neutronic reactor of the heterogeneous, fluid cooled tvpe is described. The reactor is comprised of a pressure vessel containing the moderator and a plurality of vertically disposed channels extending in spaced relationship through the moderator. Fissionable fuel material is placed within the channels in spaced relationship thereto to permit circulation of the coolant fluid. Separate means are provided for cooling the moderator and for circulating a fluid coolant thru the channel elements to cool the fuel material.

  18. NUCLEAR REACTOR

    DOEpatents

    Anderson, C.R.

    1962-07-24

    A fluidized bed nuclear reactor and a method of operating such a reactor are described. In the design means are provided for flowing a liquid moderator upwardly through the center of a bed of pellets of a nentron-fissionable material at such a rate as to obtain particulate fluidization while constraining the lower pontion of the bed into a conical shape. A smooth circulation of particles rising in the center and falling at the outside of the bed is thereby established. (AEC)

  19. NUCLEAR REACTOR

    DOEpatents

    Grebe, J.J.

    1959-07-14

    High temperature reactors which are uniquely adapted to serve as the heat source for nuclear pcwered rockets are described. The reactor is comprised essentially of an outer tubular heat resistant casing which provides the main coolant passageway to and away from the reactor core within the casing and in which the working fluid is preferably hydrogen or helium gas which is permitted to vaporize from a liquid storage tank. The reactor core has a generally spherical shape formed entirely of an active material comprised of fissile material and a moderator material which serves as a diluent. The active material is fabricated as a gas permeable porous material and is interlaced in a random manner with very small inter-connecting bores or capillary tubes through which the coolant gas may flow. The entire reactor is divided into successive sections along the direction of the temperature gradient or coolant flow, each section utilizing materials of construction which are most advantageous from a nuclear standpoint and which at the same time can withstand the operating temperature of that particular zone. This design results in a nuclear reactor characterized simultaneously by a minimum critiral size and mass and by the ability to heat a working fluid to an extremely high temperature.

  20. 45 CFR 73b.2 - Rules and regulations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 1 2012-10-01 2012-10-01 false Rules and regulations. 73b.2 Section 73b.2 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION DEBARMENT OR SUSPENSION OF FORMER... those regulations from the Assistant General Counsel, Business and Administrative Law...

  1. 45 CFR 73b.2 - Rules and regulations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Rules and regulations. 73b.2 Section 73b.2 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION DEBARMENT OR SUSPENSION OF FORMER... those regulations from the Assistant General Counsel, Business and Administrative Law...

  2. Plexin-B2 promotes invasive growth of malignant glioma.

    PubMed

    Le, Audrey P; Huang, Yong; Pingle, Sandeep C; Kesari, Santosh; Wang, Huaien; Yong, Raymund L; Zou, Hongyan; Friedel, Roland H

    2015-03-30

    Invasive growth is a major determinant of the high lethality of malignant gliomas. Plexin-B2, an axon guidance receptor important for mediating neural progenitor cell migration during development, is upregulated in gliomas, but its function therein remains poorly understood. Combining bioinformatic analyses, immunoblotting and immunohistochemistry of patient samples, we demonstrate that Plexin-B2 is consistently upregulated in all types of human gliomas and that its expression levels correlate with glioma grade and poor survival. Activation of Plexin-B2 by Sema4C ligand in glioblastoma cells induced actin-based cytoskeletal dynamics and invasive migration in vitro. This proinvasive effect was associated with activation of the cell motility mediators RhoA and Rac1. Furthermore, costimulation of Plexin-B2 and the receptor tyrosine kinase Met led to synergistic Met phosphorylation. In intracranial glioblastoma transplants, Plexin-B2 knockdown hindered invasive growth and perivascular spreading, and resulted in decreased tumor vascularity. Our results demonstrate that Plexin-B2 promotes glioma invasion and vascularization, and they identify Plexin-B2 as a potential novel prognostic marker for glioma malignancy. Targeting the Plexin-B2 pathway may represent a novel therapeutic approach to curtail invasive growth of glioblastoma.

  3. 26 CFR 1.663(b)-2 - Election.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... extensions thereof). Such election shall become irrevocable after the last day prescribed for making it. (2... election shall become irrevocable after the last day prescribed for making it. (b) Elections under prior... 26 Internal Revenue 8 2014-04-01 2014-04-01 false Election. 1.663(b)-2 Section 1.663(b)-2...

  4. 26 CFR 1.663(b)-2 - Election.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... extensions thereof). Such election shall become irrevocable after the last day prescribed for making it. (2... election shall become irrevocable after the last day prescribed for making it. (b) Elections under prior... 26 Internal Revenue 8 2013-04-01 2013-04-01 false Election. 1.663(b)-2 Section 1.663(b)-2...

  5. 26 CFR 1.663(b)-2 - Election.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... extensions thereof). Such election shall become irrevocable after the last day prescribed for making it. (2... election shall become irrevocable after the last day prescribed for making it. (b) Elections under prior... 26 Internal Revenue 8 2011-04-01 2011-04-01 false Election. 1.663(b)-2 Section 1.663(b)-2...

  6. All-MgB2 Josephson tunnel junctions

    NASA Astrophysics Data System (ADS)

    Ueda, K.; Saito, S.; Semba, K.; Makimoto, T.; Naito, M.

    2005-04-01

    Sandwich-type all-MgB2 Josephson tunnel junctions (MgB2/AlOx/MgB2) have been fabricated with as-grown MgB2 films formed by molecular-beam epitaxy. The junctions exhibit substantial superconducting current (IcRN product ˜0.8mV at 4.2 K), a well-defined superconducting gap (Δ=2.2-2.3mV), and clear Fraunhofer patterns. The superconducting gap voltage of Δ agrees well with the smaller gap in the multigap scenario. The results demonstrate that MgB2 has great promise for superconducting electronics that can be operated at T ˜20K.

  7. NEUTRONIC REACTOR

    DOEpatents

    Ohlinger, L.A.; Wigner, E.P.; Weinberg, A.M.; Young, G.J.

    1958-09-01

    This patent relates to neutronic reactors of the heterogeneous water cooled type, and in particular to a fuel element charging and discharging means therefor. In the embodiment illustrated the reactor contains horizontal, parallel coolant tubes in which the fuel elements are disposed. A loading cart containing a magnzine for holding a plurality of fuel elements operates along the face of the reactor at the inlet ends of the coolant tubes. The loading cart is equipped with a ram device for feeding fuel elements from the magazine through the inlot ends of the coolant tubes. Operating along the face adjacent the discharge ends of the tubes there is provided another cart means adapted to receive irradiated fuel elements as they are forced out of the discharge ends of the coolant tubes by the incoming new fuel elements. This cart is equipped with a tank coataining a coolant, such as water, into which the fuel elements fall, and a hydraulically operated plunger to hold the end of the fuel element being discharged. This inveation provides an apparatus whereby the fuel elements may be loaded into the reactor, irradiated therein, and unloaded from the reactor without stopping the fiow of the coolant and without danger to the operating personnel.

  8. Production and characterization of aflatoxin B2a antiserum.

    PubMed Central

    Gaur, P K; Lau, H P; Pestka, J J; Chu, F S

    1981-01-01

    The specificity and sensitivity of antiserum elicited from rabbits against aflatoxin B2a-bovine serum albumin conjugates were characterized with a radioimmunoassay (RIA) and an enzyme-linked immunosorbent assay (ELISA). Aflatoxin B1 was first converted to aflatoxin B2a and then conjugated to bovine serum albumin and horseradish peroxidase by a reductive alkylation method. The antiserum was developed in New Zealand white rabbits by multiple-site injection with the aflatoxin B2a-bovine serum albumin conjugate. Antibody titers were determined by both RIA and ELISA. Competitive RIAs with various aflatoxin analogs indicated that the antiserum was most reactive with aflatoxin B1 and slightly cross-reactive with aflatoxins B2a, B2, and M1. Competitive ELISAs showed the antiserum to be equally specific for aflatoxins B2a and B12 and less reactive with aflatoxins B2 and M1. The relative sensitivities of RIA and ELISA for aflatoxin B1 quantitation were 100 and 10 pg per assay, respectively. PMID:7235694

  9. CRADA Final Report: ErbB2 Targeted Cancer Therapeutics

    SciTech Connect

    Lupu, Ruth

    2002-08-27

    The aim of the study was to design novel therapeutic strategies for the treatment of carcinomas which overexpress the erbB-2 oncogene product and/or the activator (HRG). erbB-2 is a tyrosine kinase growth factor receptor, that overexpression of which in invasive breast, prostate, ovarian and lung carcinomas correlates with poor prognosis and poor overall survival. In breast carcinomas, erbB-2 is overexpressed in 25%-30% of the invasive phenotype and in 70% of ductal carcinomas in situ. On the other hand, the erbB-2 activator, heregulin (HRG) is expressed in about 30% of invasive breast carcinomas and it is highly expressed in other carcinoIl1as including, ovarian, lung, and prostate. Interestingly, only 6% of invasive breast carcinomas co-express both HRG and erbB-2. It is known today that tumors that overexpress erbB-2 are a leading cause of death, making erbB-2 and its activator HRG critical targets for therapy. Targeting both the receptors and the activator would be beneficial for a significant number of cancer patients. At the final stages of the project we had obtained significant improvements over the peptide quality but not significant improvements were made towards the generation of humanized monoclonal antibodies.

  10. POWER REACTOR

    DOEpatents

    Zinn, W.H.

    1958-07-01

    A fast nuclear reactor system ls described for producing power and radioactive isotopes. The reactor core is of the heterogeneous, fluid sealed type comprised of vertically arranged elongated tubular fuel elements having vertical coolant passages. The active portion is surrounded by a neutron reflector and a shield. The system includes pumps and heat exchangers for the primary and secondary coolant circuits. The core, primary coolant pump and primary heat exchanger are disposed within an irapenforate tank which is filled with the primary coolant, in this case a liquid metal such as Na or NaK, to completely submerge these elements. The tank is completely surrounded by a thick walled concrete shield. This reactor system utilizes enriched uranium or plutonium as the fissionable material, uranium or thorium as a diluent and thorium or uranium containing less than 0 7% of the U/sup 235/ isotope as a fertile material.

  11. REACTOR CONTROL

    DOEpatents

    Fortescue, P.; Nicoll, D.

    1962-04-24

    A control system employed with a high pressure gas cooled reactor in which a control rod is positioned for upward and downward movement into the neutron field from a position beneath the reactor is described. The control rod is positioned by a coupled piston cylinder releasably coupled to a power drive means and the pressurized coolant is directed against the lower side of the piston. The coolant pressure is offset by a higher fiuid pressure applied to the upper surface of the piston and means are provided for releasing the higher pressure on the upper side of the piston so that the pressure of the coolant drives the piston upwardly, forcing the coupled control rod into the ncutron field of the reactor. (AEC)

  12. Bioconversion reactor

    DOEpatents

    McCarty, Perry L.; Bachmann, Andre

    1992-01-01

    A bioconversion reactor for the anaerobic fermentation of organic material. The bioconversion reactor comprises a shell enclosing a predetermined volume, an inlet port through which a liquid stream containing organic materials enters the shell, and an outlet port through which the stream exits the shell. A series of vertical and spaced-apart baffles are positioned within the shell to force the stream to flow under and over them as it passes from the inlet to the outlet port. The baffles present a barrier to the microorganisms within the shell causing them to rise and fall within the reactor but to move horizontally at a very slow rate. Treatment detention times of one day or less are possible.

  13. NUCLEAR REACTOR

    DOEpatents

    Christy, R.F.

    1958-07-15

    A nuclear reactor of the homogeneous liquid fuel type is described wherein the fissionable isotope is suspended or dissolved in a liquid moderator such as water. The reactor core is comprised essentially of a spherical vessel for containing the reactive composition surrounded by a reflector, preferably of beryllium oxide. The reactive composition may be an ordinary water solution of a soluble salt of uranium, the quantity of fissionable isotope in solution being sufficient to provide a critical mass in the vessel. The liquid fuel is stored in a tank of non-crtttcal geometry below the reactor vessel and outside of the reflector and is passed from the tank to the vessel through a pipe connecting the two by air pressure means. Neutron absorbing control and safety rods are operated within slots in the reflector adjacent to the vessel.

  14. NEUTRONIC REACTOR

    DOEpatents

    Metcalf, H.E.

    1957-10-01

    A reactor of the type which preferably uses plutonium as the fuel and a liquid moderator, preferably ordinary water, and which produces steam within the reactor core due to the heat of the chain reaction is described. In the reactor shown the fuel elements are essentially in the form of trays and are ventically stacked in spaced relationship. The water moderator is continuously supplied to the trays to maintain a constant level on the upper surfaces of the fuel element as it is continually evaporated by the heat. The steam passes out through the spaces between the fuel elements and is drawn off at the top of the core. The fuel elements are clad in aluminum to prevent deterioration thereof with consequent contamimation of the water.

  15. NEUTRONIC REACTORS

    DOEpatents

    Wigner, E.P.; Young, G.J.

    1958-10-14

    A method is presented for loading and unloading rod type fuel elements of a neutronic reactor of the heterogeneous, solld moderator, liquid cooled type. In the embodiment illustrated, the fuel rods are disposed in vertical coolant channels in the reactor core. The fuel rods are loaded and unloaded through the upper openings of the channels which are immersed in the coolant liquid, such as water. Unloading is accomplished by means of a coffer dam assembly having an outer sleeve which is placed in sealing relation around the upper opening. A radiation shield sleeve is disposed in and reciprocable through the coffer dam sleeve. A fuel rod engaging member operates through the axial bore in the radiation shield sleeve to withdraw the fuel rod from its position in the reactor coolant channel into the shield, the shield snd rod then being removed. Loading is accomplished in the reverse procedure.

  16. Catalytic reactor

    SciTech Connect

    Aaron, Timothy Mark; Shah, Minish Mahendra; Jibb, Richard John

    2009-03-10

    A catalytic reactor is provided with one or more reaction zones each formed of set(s) of reaction tubes containing a catalyst to promote chemical reaction within a feed stream. The reaction tubes are of helical configuration and are arranged in a substantially coaxial relationship to form a coil-like structure. Heat exchangers and steam generators can be formed by similar tube arrangements. In such manner, the reaction zone(s) and hence, the reactor is compact and the pressure drop through components is minimized. The resultant compact form has improved heat transfer characteristics and is far easier to thermally insulate than prior art compact reactor designs. Various chemical reactions are contemplated within such coil-like structures such that as steam methane reforming followed by water-gas shift. The coil-like structures can be housed within annular chambers of a cylindrical housing that also provide flow paths for various heat exchange fluids to heat and cool components.

  17. Operational Art in the 1944 Ardennes Campaign

    DTIC Science & Technology

    1987-05-10

    Dyer, LTC George. =T Cor2s: Spearhead of Patton’s Third m y I Corps History Association, 1947. Eisenhower, John S. D. The Bitter Woods. Putnam’s, New...1984. Published in the U.S. as & Time for Trumoes. Mellenthln, Friedrich Wilhem von, Panzer Battle,% A Study of the Eunloyment of Armor In the Second...Cornell University Press, Ithaca, New York, 1984. Toland, John , Battle - The Story of the 1u3tge. Random House, New York, 1959. Weigley, Russell F

  18. NEUTRONIC REACTOR

    DOEpatents

    Fermi, E.; Szilard, L.

    1957-09-24

    Reactors of the type employing plates of natural uranium in a moderator are discussed wherein the plates are um-formly disposed in parallel relationship to each other thereby separating the moderator material into distinct and individual layers. Each plate has an uninterrupted sunface area substantially equal to the cross-sectional area of the active portion of the reactor, the particular size of the plates and the volume ratio of moderator to uranium required to sustain a chain reaction being determinable from the known purity of these materials and other characteristics such as the predictable neutron losses due to the formation of radioactive elements of extremely high neutron capture cross section.

  19. NEUTRONIC REACTOR

    DOEpatents

    Wigner, E.P.; Weinberg, A.W.; Young, G.J.

    1958-04-15

    A nuclear reactor which uses uranium in the form of elongated tubes as fuel elements and liquid as a coolant is described. Elongated tubular uranium bodies are vertically disposed in an efficient neutron slowing agent, such as graphite, for example, to form a lattice structure which is disposed between upper and lower coolant tanks. Fluid coolant tubes extend through the uranium bodies and communicate with the upper and lower tanks and serve to convey the coolant through the uranium body. The reactor is also provided with means for circulating the cooling fluid through the coolant tanks and coolant tubes, suitable neutron and gnmma ray shields, and control means.

  20. Properties of L=1 B(1) and B(2)* mesons.

    PubMed

    Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Aguilo, E; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Ancu, L S; Andeen, T; Anderson, S; Andrieu, B; Anzelc, M S; Arnoud, Y; Arov, M; Arthaud, M; Askew, A; Asman, B; Assis Jesus, A C S; Atramentov, O; Autermann, C; Avila, C; Ay, C; Badaud, F; Baden, A; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, S; Banerjee, P; Barberis, E; Barfuss, A-F; Bargassa, P; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Bellavance, A; Benitez, J A; Beri, S B; Bernardi, G; Bernhard, R; Berntzon, L; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Biscarat, C; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Borissov, G; Bos, K; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Buchanan, N J; Buchholz, D; Buehler, M; Buescher, V; Burdin, S; Burke, S; Burnett, T H; Buszello, C P; Butler, J M; Calfayan, P; Calvet, S; Cammin, J; Caron, S; Carvalho, W; Casey, B C K; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chan, K; Chandra, A; Charles, F; Cheu, E; Chevallier, F; Cho, D K; Choi, S; Choudhary, B; Christofek, L; Christoudias, T; Cihangir, S; Claes, D; Clément, C; Clément, B; Coadou, Y; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M-C; Crépé-Renaudin, S; Cutts, D; Cwiok, M; da Motta, H; Das, A; Davies, G; De, K; de Jong, S J; de Jong, P; De La Cruz-Burelo, E; Martins, C De Oliveira; Degenhardt, J D; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Dominguez, A; Dong, H; Dudko, L V; Duflot, L; Dugad, S R; Duggan, D; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Ermolov, P; Evans, H; Evdokimov, A; Evdokimov, V N; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Ford, M; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; Garcia, C; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Gelé, D; Gerber, C E; Gershtein, Y; Gillberg, D; Ginther, G; Gollub, N; Gómez, B; Goussiou, A; Grannis, P D; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, J; Guo, F; Gutierrez, P; Gutierrez, G; Haas, A; Hadley, N J; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Hanagaki, K; Hansson, P; Harder, K; Harel, A; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hoeth, H; Hohlfeld, M; Hong, S J; Hooper, R; Hossain, S; Houben, P; Hu, Y; Hubacek, Z; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jarvis, C; Jesik, R; Johns, K; Johnson, C; Johnson, M; Jonckheere, A; Jonsson, P; Juste, A; Käfer, D; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J R; Kalk, J M; Kappler, S; Karmanov, D; Kasper, J; Kasper, P; Katsanos, I; Kau, D; Kaur, R; Kaushik, V; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y M; Khatidze, D; Kim, H; Kim, T J; Kirby, M H; Kirsch, M; Klima, B; Kohli, J M; Konrath, J-P; Kopal, M; Korablev, V M; Kothari, B; Kozelov, A V; Krop, D; Kryemadhi, A; Kuhl, T; Kumar, A; Kunori, S; Kupco, A; Kurca, T; Kvita, J; Lacroix, F; Lam, D; Lammers, S; Landsberg, G; Lazoflores, J; Lebrun, P; Lee, W M; Leflat, A; Lehner, F; Lellouch, J; Lesne, V; Leveque, J; Lewis, P; Li, J; Li, Q Z; Li, L; Lietti, S M; Lima, J G R; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobo, L; Lobodenko, A; Lokajicek, M; Lounis, A; Love, P; Lubatti, H J; Lyon, A L; Maciel, A K A; Mackin, D; Madaras, R J; Mättig, P; Magass, C; Magerkurth, A; Makovec, N; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martin, B; McCarthy, R; Melnitchouk, A; Mendes, A; Mendoza, L; Mercadante, P G; Merkin, M; Merritt, K W; Meyer, J; Meyer, A; Michaut, M; Millet, T; Mitrevski, J; Molina, J; Mommsen, R K; Mondal, N K; Moore, R W; Moulik, T; Muanza, G S; Mulders, M; Mulhearn, M; Mundal, O; Mundim, L; Nagy, E; Naimuddin, M; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Neustroev, P; Nilsen, H; Nomerotski, A; Novaes, S F; Nunnemann, T; O'Dell, V; O'Neil, D C; Obrant, G; Ochando, C; Onoprienko, D; Oshima, N; Osta, J; Otec, R; Y Garzón, G J Otero; Owen, M; Padley, P; Pangilinan, M; Parashar, N; Park, S-J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Penning, B; Perea, P M; Peters, K; Peters, Y; Pétroff, P; Petteni, M; Piegaia, R; Piper, J; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M-E; Polozov, P; Pompos, A; Pope, B G; Popov, A V; Potter, C; da Silva, W L Prado; Prosper, H B; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rakitine, A; Rangel, M S; Rani, K J; Ranjan, K; Ratoff, P N; Renkel, P; Reucroft, S; Rich, P; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Robinson, S; Rodrigues, R F; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Santoro, A; Savage, G; Sawyer, L; Scanlon, T; Schaile, D; Schamberger, R D; Scheglov, Y; Schellman, H; Schieferdecker, P; Schliephake, T; Schmitt, C; Schwanenberger, C; Schwartzman, A; Schwienhorst, R; Sekaric, J; Sengupta, S; Severini, H; Shabalina, E; Shamim, M; Shary, V; Shchukin, A A; Shivpuri, R K; Shpakov, D; Siccardi, V; Simak, V; Sirotenko, V; Skubic, P; Slattery, P; Smirnov, D; Smith, R P; Snow, J; Snow, G R; Snyder, S; Söldner-Rembold, S; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Souza, M; Spurlock, B; Stark, J; Steele, J; Stolin, V; Stone, A; Stoyanova, D A; Strandberg, J; Strandberg, S; Strang, M A; Strauss, M; Strauss, E; Ströhmer, R; Strom, D; Strovink, M; Stutte, L; Sumowidagdo, S; Svoisky, P; Sznajder, A; Talby, M; Tamburello, P; Tanasijczuk, A; Taylor, W; Telford, P; Temple, J; Tiller, B; Tissandier, F; Titov, M; Tokmenin, V V; Tomoto, M; Toole, T; Torchiani, I; Trefzger, T; Tsybychev, D; Tuchming, B; Tully, C; Tuts, P M; Unalan, R; Uvarov, S; Uvarov, L; Uzunyan, S; Vachon, B; van den Berg, P J; van Eijk, B; Van Kooten, R; van Leeuwen, W M; Varelas, N; Varnes, E W; Vartapetian, A; Vasilyev, I A; Vaupel, M; Verdier, P; Vertogradov, L S; Verzocchi, M; Villeneuve-Seguier, F; Vint, P; Vokac, P; Von Toerne, E; Voutilainen, M; Vreeswijk, M; Wagner, R; Wahl, H D; Wang, L; Wang, M H L S; Warchol, J; Watts, G; Wayne, M; Weber, M; Weber, G; Weerts, H; Wenger, A; Wermes, N; Wetstein, M; White, A; Wicke, D; Wilson, G W; Williams, M R J; Wimpenny, S J; Wobisch, M; Wood, D R; Wyatt, T R; Xie, Y; Yacoob, S; Yamada, R; Yan, M; Yasuda, T; Yatsunenko, Y A; Yip, K; Yoo, H D; Youn, S W; Yu, J; Yu, C; Yurkewicz, A; Zatserklyaniy, A; Zeitnitz, C; Zhang, D; Zhao, T; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zieminski, A; Zivkovic, L; Zutshi, V; Zverev, E G

    2007-10-26

    This Letter presents the first strong evidence for the resolution of the excited B mesons B(1) and B(2)* as two separate states in fully reconstructed decays to B(+)(*)pi(-). The mass of B(1) is measured to be 5720.6+/-2.4+/-1.4 MeV/c(2) and the mass difference DeltaM between B(2)* and B(1) is 26.2+/-3.1+/-0.9 MeV/c;{2}, giving the mass of the B(2)* as 5746.8+/-2.4+/-1.7 MeV/c(2). The production rate for B(1) and B(2)* mesons is determined to be a fraction (13.9+/-1.9+/-3.2)% of the production rate of the B+ meson.

  1. Al addition effect of bulk MgB 2 superconductor

    NASA Astrophysics Data System (ADS)

    Shinohara, K.; Ikeda, H.; Yoshizaki, R.

    2007-10-01

    The properties of transport and magnetization have been investigated for bulk MgB2Alx superconductor with Al addition (x = 0, 0.5, 1 wt%). MgB2 bulk samples sintered at different temperatures at 650-740 °C were prepared in the undoped state. The temperature and applied field dependencies of resistivity and magnetization were measured for the samples. The sample sintered at 690 °C exhibited the highest critical current density (Jc) and the lowest resistivity. This undoped sample was chosen as a criterion sample, and the effect of Al addition on the MgB2 bulk was studied from the transport and magnetization properties in a magnetic field. For MgB2Alx bulk samples sintered at 690 °C, the resistivity increased and Jc decreased as amount of Al was increased.

  2. Improvement in the transport critical current density and microstructure of isotopic Mg11B2 monofilament wires by optimizing the sintering temperature

    NASA Astrophysics Data System (ADS)

    Qiu, Wenbin; Jie, Hyunseock; Patel, Dipak; Lu, Yao; Luzin, Vladimir; Devred, Arnaud; Somer, Mehmet; Shahabuddin, Mohammed; Kim, Jung Ho; Ma, Zongqing; Dou, Shi Xue; Hossain, Md. Shahriar Al

    2016-11-01

    Superconducting wires are widely used in fabricating magnetic coils in fusion reactors. In consideration of the stability of 11B against neutron irradiation and lower induced radio-activation properties, MgB2 superconductor with 11B serving as boron source is an alternative candidate to be used in fusion reactor with severe irradiation environment. In present work, a batch of monofilament isotopic Mg11B2 wires with amorphous 11B powder as precursor were fabricated using powder-in-tube (PIT) process at different sintering temperature, and the evolution of their microstructure and corresponding superconducting properties was systemically investigated. Accordingly, the best transport critical current density (Jc) = 2 × 104 A/cm2 was obtained at 4.2 K and 5 T, which is even comparable to multi-filament Mg11B2 isotope wires reported in other work. Surprisingly, transport Jc vanished in our wire which was heat-treated at excessively high temperature (800 °C). Combined with microstructure observation, it was found that lots of big interconnected microcracks and voids that can isolate the MgB2 grains formed in this whole sample, resulting in significant deterioration in inter-grain connectivity. The results can be a constructive guide in fabricating Mg11B2 wires to be used as magnet coils in fusion reactor systems such as ITER-type tokamak magnet.

  3. Improvement in the transport critical current density and microstructure of isotopic Mg(11)B2 monofilament wires by optimizing the sintering temperature.

    PubMed

    Qiu, Wenbin; Jie, Hyunseock; Patel, Dipak; Lu, Yao; Luzin, Vladimir; Devred, Arnaud; Somer, Mehmet; Shahabuddin, Mohammed; Kim, Jung Ho; Ma, Zongqing; Dou, Shi Xue; Hossain, Md Shahriar Al

    2016-11-08

    Superconducting wires are widely used in fabricating magnetic coils in fusion reactors. In consideration of the stability of (11)B against neutron irradiation and lower induced radio-activation properties, MgB2 superconductor with (11)B serving as boron source is an alternative candidate to be used in fusion reactor with severe irradiation environment. In present work, a batch of monofilament isotopic Mg(11)B2 wires with amorphous (11)B powder as precursor were fabricated using powder-in-tube (PIT) process at different sintering temperature, and the evolution of their microstructure and corresponding superconducting properties was systemically investigated. Accordingly, the best transport critical current density (Jc) = 2 × 10(4) A/cm(2) was obtained at 4.2 K and 5 T, which is even comparable to multi-filament Mg(11)B2 isotope wires reported in other work. Surprisingly, transport Jc vanished in our wire which was heat-treated at excessively high temperature (800 °C). Combined with microstructure observation, it was found that lots of big interconnected microcracks and voids that can isolate the MgB2 grains formed in this whole sample, resulting in significant deterioration in inter-grain connectivity. The results can be a constructive guide in fabricating Mg(11)B2 wires to be used as magnet coils in fusion reactor systems such as ITER-type tokamak magnet.

  4. Improvement in the transport critical current density and microstructure of isotopic Mg11B2 monofilament wires by optimizing the sintering temperature

    PubMed Central

    Qiu, Wenbin; Jie, Hyunseock; Patel, Dipak; Lu, Yao; Luzin, Vladimir; Devred, Arnaud; Somer, Mehmet; Shahabuddin, Mohammed; Kim, Jung Ho; Ma, Zongqing; Dou, Shi Xue; Hossain, Md. Shahriar Al

    2016-01-01

    Superconducting wires are widely used in fabricating magnetic coils in fusion reactors. In consideration of the stability of 11B against neutron irradiation and lower induced radio-activation properties, MgB2 superconductor with 11B serving as boron source is an alternative candidate to be used in fusion reactor with severe irradiation environment. In present work, a batch of monofilament isotopic Mg11B2 wires with amorphous 11B powder as precursor were fabricated using powder-in-tube (PIT) process at different sintering temperature, and the evolution of their microstructure and corresponding superconducting properties was systemically investigated. Accordingly, the best transport critical current density (Jc) = 2 × 104 A/cm2 was obtained at 4.2 K and 5 T, which is even comparable to multi-filament Mg11B2 isotope wires reported in other work. Surprisingly, transport Jc vanished in our wire which was heat-treated at excessively high temperature (800 °C). Combined with microstructure observation, it was found that lots of big interconnected microcracks and voids that can isolate the MgB2 grains formed in this whole sample, resulting in significant deterioration in inter-grain connectivity. The results can be a constructive guide in fabricating Mg11B2 wires to be used as magnet coils in fusion reactor systems such as ITER-type tokamak magnet. PMID:27824144

  5. Mechanical and thermal properties of bulk ZrB2

    NASA Astrophysics Data System (ADS)

    Nakamori, Fumihiro; Ohishi, Yuji; Muta, Hiroaki; Kurosaki, Ken; Fukumoto, Ken-ichi; Yamanaka, Shinsuke

    2015-12-01

    ZrB2 appears to have formed in the fuel debris at the Fukushima Daiichi nuclear disaster site, through the reaction between Zircaloy cladding materials and the control rod material B4C. Since ZrB2 has a high melting point of 3518 K, the ceramic has been widely studied as a heat-resistant material. Although various studies on the thermochemical and thermophysical properties have been performed for ZrB2, significant differences exist in the data, possibly due to impurities or the porosity within the studied samples. In the present study, we have prepared a ZrB2 bulk sample with 93.1% theoretical density by sintering ZrB2 powder. On this sample, we have comprehensively examined the thermal and mechanical properties of ZrB2 by the measurement of specific heat, ultrasonic sound velocities, thermal diffusivity, and thermal expansion. Vickers hardness and fracture toughness were also measured and found to be 13-23 GPa and 1.8-2.8 MPa m0.5, respectively. The relationships between these properties were carefully examined in the present study.

  6. Magnetic lenses using different MgB2 bulk superconductors

    NASA Astrophysics Data System (ADS)

    Zhang, Z. Y.; Choi, S.; Matsumoto, S.; Teranishi, R.; Giunchi, G.; Figini Albisetti, A.; Kiyoshi, T.

    2012-02-01

    A magnetic lens allows the concentration of magnetic fields using the diamagnetism of superconductors. The important features of the magnetic lens are a tapered inner diameter from which the magnetic flux is extruded and a slit to suppress the circumference current that shields the magnetic flux. This concept was experimentally confirmed through the use of GdBaCuO bulks and a stack of NbTi/Nb/Cu sheets. We refer to this arrangement as a magnetic lens. The Mg-reactive liquid infiltration (Mg-RLI) process developed by Edison SpA is suitable for the production of large and high-density MgB2 bulks. Three MgB2 bulk magnetic lenses, each with a different microstructure, were fabricated following the Mg-RLI process. The properties of the MgB2 magnetic lenses were measured in a cryocooler system as well as in liquid helium. The results confirmed that the MgB2 bulk magnetic lenses could concentrate a magnetic field and that their field concentration properties were greatly affected by the temperature and the external field. In addition, the microstructure of the MgB2 bulk also had an influence on the magnetic properties at different external fields. The results indicated that the MgB2 lens might be utilized as a field amplifier in intermediate fields.

  7. Memo mediates ErbB2-driven cell motility.

    PubMed

    Marone, Romina; Hess, Daniel; Dankort, David; Muller, William J; Hynes, Nancy E; Badache, Ali

    2004-06-01

    Clinical studies have revealed that cancer patients whose tumours have increased ErbB2 expression tend to have more aggressive, metastatic disease, which is associated with parameters predicting a poor outcome. The molecular basis underlying ErbB2-dependent cell motility and metastases formation, however, still remains poorly understood. In this study, we show that activation of a set of signalling molecules, including MAPK, phosphatidylinositol-3-OH kinase (PI(3)K) and Src, is required for Neu/ErbB2-dependent lamellipodia formation and for motility of breast carcinoma cells. Stimulation of these molecules, however, failed to induce efficient cell migration in the absence of Neu/ErbB2 phosphorylation at Tyr 1201 or Tyr 1227. We describe a novel molecule, Memo (mediator of ErbB2-driven cell motility), that interacts with a phospho-Tyr 1227-containing peptide, most probably through the Shc adaptor protein. After Neu/ErbB2 activation, Memo-defective cells form actin fibres and grow lamellipodia, but fail to extend microtubules towards the cell cortex. Our data suggest that Memo controls cell migration by relaying extracellular chemotactic signals to the microtubule cytoskeleton.

  8. Neutronic reactor

    DOEpatents

    Wende, Charles W. J.

    1976-08-17

    A safety rod for a nuclear reactor has an inner end portion having a gamma absorption coefficient and neutron capture cross section approximately equal to those of the adjacent shield, a central portion containing materials of high neutron capture cross section and an outer end portion having a gamma absorption coefficient at least equal to that of the adjacent shield.

  9. Neutronic reactor

    DOEpatents

    Carleton, John T.

    1977-01-25

    A graphite-moderated nuclear reactor includes channels between blocks of graphite and also includes spacer blocks between adjacent channeled blocks with an axis of extension normal to that of the axis of elongation of the channeled blocks to minimize changes in the physical properties of the graphite as a result of prolonged neutron bombardment.

  10. Sonochemical Reactors.

    PubMed

    Gogate, Parag R; Patil, Pankaj N

    2016-10-01

    Sonochemical reactors are based on the generation of cavitational events using ultrasound and offer immense potential for the intensification of physical and chemical processing applications. The present work presents a critical analysis of the underlying mechanisms for intensification, available reactor configurations and overview of the different applications exploited successfully, though mostly at laboratory scales. Guidelines have also been presented for optimum selection of the important operating parameters (frequency and intensity of irradiation, temperature and liquid physicochemical properties) as well as the geometric parameters (type of reactor configuration and the number/position of the transducers) so as to maximize the process intensification benefits. The key areas for future work so as to transform the successful technique at laboratory/pilot scale into commercial technology have also been discussed. Overall, it has been established that there is immense potential for sonochemical reactors for process intensification leading to greener processing and economic benefits. Combined efforts from a wide range of disciplines such as material science, physics, chemistry and chemical engineers are required to harness the benefits at commercial scale operation.

  11. NEUTRONIC REACTORS

    DOEpatents

    Anderson, H.L.

    1958-10-01

    The design of control rods for nuclear reactors are described. In this design the control rod consists essentially of an elongated member constructed in part of a neutron absorbing material and having tube means extending therethrough for conducting a liquid to cool the rod when in use.

  12. NEUTRONIC REACTOR

    DOEpatents

    Creutz, E.C.; Ohlinger, L.A.; Weinberg, A.M.; Wigner, E.P.; Young, G.J.

    1959-10-27

    BS>A reactor cooled by water, biphenyl, helium, or other fluid with provision made for replacing the fuel rods with the highest plutonium and fission product content without disassembling the entire core and for promptly cooling the rods after their replacement in order to prevent build-up of heat from fission product activity is described.

  13. B-B bond activation and NHC ring-expansion reactions of diboron(4) compounds, and accurate molecular structures of B2(NMe2)4, B2eg2, B2neop2 and B2pin2.

    PubMed

    Eck, Martin; Würtemberger-Pietsch, Sabrina; Eichhorn, Antonius; Berthel, Johannes H J; Bertermann, Rüdiger; Paul, Ursula S D; Schneider, Heidi; Friedrich, Alexandra; Kleeberg, Christian; Radius, Udo; Marder, Todd B

    2017-03-14

    In this detailed study we report on the structures of the widely employed diboron(4) compounds bis(pinacolato)diboron (B2pin2) and bis(neopentyl glycolato)diboron (B2neop2), as well as bis(ethylene glycolato)diboron (B2eg2) and tetrakis(dimethylamino)diboron (B2(NMe2)4), and their reactivity, along with that of bis(catecholato)diboron (B2cat2) with backbone saturated and backbone unsaturared N-heterocyclic carbenes (NHCs) of different steric demand. Depending on the nature of the diboron(4) compound and the NHC used, Lewis-acid/Lewis-base adducts or NHC ring-expansion products stemming from B-B and C-N bond activation have been observed. The corresponding NHC adducts and NHC ring-expanded products were isolated and characterised via solid-state and solution NMR spectroscopy and X-ray diffraction. In general, we observed B-B bond and C-N bond activation at low temperature for B2eg2, at room temperature for B2neop2 and at higher temperature for B2cat2. The reactivity strongly depends on steric effects of the NHCs and the diboron(4) compounds, as well as on the corresponding Lewis-basicity and Lewis-acidity. Our results provide profound insight into the chemistry of these diboron(4) reagents with the nowadays ubiquitous NHCs, the stability of the corresponding NHC adducts and on B-B bond activation using Lewis-bases in general. We demonstrate that B-B bond activation may be triggered even at temperatures as low as -40 °C to -30 °C without any metal species involved. For example, the reactions of B2eg2 with sterically less demanding NHCs such as Me2Im(Me) and iPr2Im in solution led to the corresponding ring-expanded products at low temperatures. Furthermore, boronium [L2B(OR)2](+) and borenium [LB(OR)2](+) cations have been observed from the reaction of the bis-borate B2eg3 with the NHCs iPr2Im and Me2Im(Me), which led to the conclusion that the activation of bis-borates with NHCs (or Lewis-bases in general) might be a facile and simple route to access such species.

  14. Epitaxial MgB2 thin films on ZrB2 buffer layers: structural characterization by synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Ferrando, V.; Tarantini, C.; Bellingeri, E.; Manfrinetti, P.; Pallecchi, I.; Marré, D.; Plantevin, O.; Putti, M.; Felici, R.; Ferdeghini, C.

    2004-12-01

    Structural and superconducting properties of magnesium diboride thin films grown by pulsed laser deposition on zirconium diboride buffer layers were studied. We demonstrate that the ZrB2 layer is compatible with the MgB2 two step deposition process. Synchrotron radiation measurements, in particular anomalous diffraction measurements, allowed us to separate MgB2 peaks from ZrB2 ones and revealed that both layers have a single in plane orientation with a sharp interface between them. Moreover, the buffer layer avoids oxygen contamination from the sapphire substrate. The critical temperature of this film is near 37.6 K and the upper critical field measured at the Grenoble High Magnetic Field Laboratory up to 20.3 T is comparable with the highest ones reported in literature.

  15. Lattice Thermal Conductivity of Ultra High Temperature Ceramics ZrB2 and HfB2 from Atomistic Simulations

    NASA Technical Reports Server (NTRS)

    Lawson, John W.; Murray, Daw S.; Bauschlicher, Charles W., Jr.

    2011-01-01

    Atomistic Green-Kubo simulations are performed to evaluate the lattice thermal conductivity for single crystals of the ultra high temperature ceramics ZrB2 and HfB2 for a range of temperatures. Recently developed interatomic potentials are used for these simulations. Heat current correlation functions show rapid oscillations which can be identified with mixed metal-Boron optical phonon modes. Agreement with available experimental data is good.

  16. Theory of B(2)O and BeB(2) nanotubes: new semiconductors and metals in one dimension.

    PubMed

    Zhang, Peihong; Crespi, Vincent H

    2002-07-29

    We describe two new boron-based nanotubes: B(2)O and BeB(2). Both are isoelectronic to graphite, have reasonable curvature energies, and have already been made in their bulk planar forms. The lowest energy allotrope of planar single-layer B(2)O is a semiconductor with a moderate band gap. The local density approximation band gap of the corresponding (3,0) B(2)O nanotube [similar in size to (9,0) carbon nanotube tube] is direct and around 1.6 eV, within a range inaccessible to previous C or BN nanotubes. Single-layer BeB(2) has a fascinating structure: the Be atoms rest above the boron hexagonal faces, nearly coplanar to the boron sheet. The unusual K-point pi-pi(*) Fermi-level degeneracy of graphite survives, while a new nearly pointlike Fermi surface appears at the M point. As a result, BeB(2) nanotubes are uniformly metallic.

  17. NUCLEAR REACTOR

    DOEpatents

    Treshow, M.

    1958-08-19

    A neuclear reactor is described of the heterogeneous type and employing replaceable tubular fuel elements and heavy water as a coolant and moderator. A pluraltty of fuel tubesa having their axes parallel, extend through a tank type pressure vessel which contatns the liquid moderator. The fuel elements are disposed within the fuel tubes in the reaetive portion of the pressure vessel during normal operation and the fuel tubes have removable plug members at each end to permit charging and discharging of the fuel elements. The fuel elements are cylindrical strands of jacketed fissionable material having helical exterior ribs. A bundle of fuel elements are held within each fuel tube with their longitudinal axes parallel, the ribs serving to space them apart along their lengths. Coolant liquid is circulated through the fuel tubes between the spaced fuel elements. Suitable control rod and monitoring means are provided for controlling the reactor.

  18. NEUTRONIC REACTOR

    DOEpatents

    Wade, E.J.

    1958-09-16

    This patent relates to a reflector means for a neutronic reactor. A reflector comprised of a plurality of vertically movable beryllium control members is provided surrounding the sides of the reactor core. An absorber of fast neutrons comprised of natural uramum surrounds the reflector. An absorber of slow neutrons surrounds the absorber of fast neutrons and is formed of a plurality of beryllium blocks having natural uranium members distributcd therethrough. in addition, a movable body is positioned directly below the core and is comprised of a beryllium reflector and an absorbing member attached to the botiom thereof, the absorbing member containing a substance selected from the goup consisting of natural urantum and Th/sup 232/.

  19. NUCLEAR REACTOR

    DOEpatents

    Grebe, J.J.

    1959-12-15

    A reactor which is particularly adapted tu serve as a heat source for a nuclear powered alrcraft or rocket is described. The core of this reactor consists of a porous refractory modera;or body which is impregnated with fissionable nuclei. The core is designed so that its surface forms tapered inlet and outlet ducts which are separated by the porous moderator body. In operation a gaseous working fluid is circulated through the inlet ducts to the surface of the moderator, enters and passes through the porous body, and is heated therein. The hot gas emerges into the outlet ducts and is available to provide thrust. The principle advantage is that tremendous quantities of gas can be quickly heated without suffering an excessive pressure drop.

  20. Nuclear reactor

    DOEpatents

    Wade, Elman E.

    1979-01-01

    A nuclear reactor including two rotatable plugs and a positive top core holddown structure. The top core holddown structure is divided into two parts: a small core cover, and a large core cover. The small core cover, and the upper internals associated therewith, are attached to the small rotating plug, and the large core cover, with its associated upper internals, is attached to the large rotating plug. By so splitting the core holddown structures, under-the-plug refueling is accomplished without the necessity of enlarging the reactor pressure vessel to provide a storage space for the core holddown structure during refueling. Additionally, the small and large rotating plugs, and their associated core covers, are arranged such that the separation of the two core covers to permit rotation is accomplished without the installation of complex lifting mechanisms.

  1. REACTOR UNLOADING

    DOEpatents

    Leverett, M.C.

    1958-02-18

    This patent is related to gas cooled reactors wherein the fuel elements are disposed in vertical channels extending through the reactor core, the cooling gas passing through the channels from the bottom to the top of the core. The invention is a means for unloading the fuel elements from the core and comprises dump values in the form of flat cars mounted on wheels at the bottom of the core structure which support vertical stacks of fuel elements. When the flat cars are moved, either manually or automatically, for normal unloading purposes, or due to a rapid rise in the reproduction ratio within the core, the fuel elements are permtted to fall by gravity out of the core structure thereby reducing the reproduction ratio or stopping the reaction as desired.

  2. NUCLEAR REACTORS

    DOEpatents

    Koch, L.J.; Rice, R.E. Jr.; Denst, A.A.; Rogers, A.J.; Novick, M.

    1961-12-01

    An active portion assembly for a fast neutron reactor is described wherein physical distortions resulting in adverse changes in the volume-to-mass ratio are minimized. A radially expandable locking device is disposed within a cylindrical tube within each fuel subassembly within the active portion assembly, and clamping devices expandable toward the center of the active portion assembly are disposed around the periphery thereof. (AEC)

  3. Neutronic reactor

    DOEpatents

    Lewis, Warren R.

    1978-05-30

    A graphite-moderated, water-cooled nuclear reactor including a plurality of rectangular graphite blocks stacked in abutting relationship in layers, alternate layers having axes which are normal to one another, alternate rows of blocks in alternate layers being provided with a channel extending through the blocks, said channeled blocks being provided with concave sides and having smaller vertical dimensions than adjacent blocks in the same layer, there being nuclear fuel in the channels.

  4. NUCLEAR REACTOR

    DOEpatents

    Grebe, J.J.

    1961-01-24

    A core structure for neutronic reactors adapted for the propulsion of aircraft and rockets is offered. The core is designed for cooling by gaseous media, and comprises a plurality of hollow tapered tubular segments of a porous moderating material impregniated with fissionable fuel nested about a common axis. Alternate ends of the segments are joined. In operation a coolant gas passes through the porous structure and is heated.

  5. NUCLEAR REACTORS

    DOEpatents

    Long, E.; Ashby, J.W.

    1958-09-16

    ABS>A graphite moderator structure is presented for a nuclear reactor compriscd of an assembly of similarly orientated prismatic graphite blocks arranged on spaced longitudinal axes lying in common planes wherein the planes of the walls of the blocks are positioned so as to be twisted reintive to the planes of said axes so thatthe unlmpeded dtrect paths in direction wholly across the walls of the blocks are limited to the width of the blocks plus spacing between the blocks.

  6. REACTOR CONTROL

    DOEpatents

    Ruano, W.J.

    1957-12-10

    This patent relates to nuclear reactors of the type which utilize elongited rod type fuel elements immersed in a liquid moderator and shows a design whereby control of the chain reaction is obtained by varying the amount of moderator or reflector material. A central tank for containing liquid moderator and fuel elements immersed therein is disposed within a surrounding outer tank providing an annular space between the two tanks. This annular space is filled with liquid moderator which functions as a reflector to reflect neutrons back into the central reactor tank to increase the reproduction ratio. Means are provided for circulating and cooling the moderator material in both tanks and additional means are provided for controlling separately the volume of moderator in each tank, which latter means may be operated automatically by a neutron density monitoring device. The patent also shows an arrangement for controlling the chain reaction by injecting and varying an amount of poisoning material in the moderator used in the reflector portion of the reactor.

  7. EBSD analysis of MgB2 bulk superconductors

    NASA Astrophysics Data System (ADS)

    Koblischka-Veneva, A.; Koblischka, M. R.; Schmauch, J.; Inoue, K.; Muralidhar, M.; Berger, K.; Noudem, J.

    2016-04-01

    The grain orientation, the texture and the grain boundary misorientations are important parameters for the understanding of the magnetic properties of the bulk MgB2 samples intended for super-magnet applications. Such data can be provided by electron backscatter diffraction (EBSD) analysis. However, as the grain size (GS) of the MgB2 bulks is preferably in the 100-200 nm range, the common EBSD technique working in reflection operates properly only on highly dense samples. In order to achieve a reasonably good Kikuchi pattern quality on all samples, we apply here the newly developed transmission EBSD (t-EBSD) technique to several bulk MgB2 samples. This method requires the preparation of TEM slices by means of focused ion-beam milling, which are then analyzed within the SEM, operating with a specific sample holder. We present several EBSD mappings of samples prepared with different techniques and at various reaction temperatures.

  8. The 23 K superconducting phase YPd 2B 2C

    NASA Astrophysics Data System (ADS)

    Sun, Y. Y.; Rusakova, I.; Meng, R. L.; Cao, Y.; Gautier-Picard, P.; Chu, C. W.

    1994-09-01

    We have carried out a systematic structural, electric, and magnetic study on YPdBC samples with different compositions with emphasis on the as-cast and annealed YPd 5B 3C 0.3 which was first reported to superconduct at ∼ 23 K by Cava et al. We found that the tetragonal body-centered YPd 2B 2C with lattice parameters a=3.71 Å and c=10.81 Å is the phase responsible for the 23 K superconductivity and that YPd 2B 2C is metastable, which is consistent with the suggestion made by Cava et al. [1]: it is not stable at high temperatures nor stabilizable by Ni doping, although its isostructural compound, YNi 2B 2C, exists. Two new phases with Y:Pd ratios of 1:7 and 2:3, respectively, have also bee detected.

  9. Neuroendocrine secretory protein 7B2: structure, expression and functions.

    PubMed Central

    Mbikay, M; Seidah, N G; Chrétien, M

    2001-01-01

    7B2 is an acidic protein residing in the secretory granules of neuroendocrine cells. Its sequence has been elucidated in many phyla and species. It shows high similarity among mammals. A Pro-Pro-Asn-Pro-Cys-Pro polyproline motif is its most conserved feature, being carried by both vertebrate and invertebrate sequences. It is biosynthesized as a precursor protein that is cleaved into an N-terminal fragment and a C-terminal peptide. In neuroendocrine cells, 7B2 functions as a specific chaperone for the proprotein convertase (PC) 2. Through the sequence around its Pro-Pro-Asn-Pro-Cys-Pro motif, it binds to an inactive proPC2 and facilitates its transport from the endoplasmic reticulum to later compartments of the secretory pathway where the zymogen is proteolytically matured and activated. Its C-terminal peptide can inhibit PC2 in vitro and may contribute to keep the enzyme transiently inactive in vivo. The PC2-7B2 model defines a new neuroendocrine paradigm whereby proteolytic activation of prohormones and proneuropeptides in the secretory pathway is spatially and temporally regulated by the dynamics of interactions between converting enzymes and their binding proteins. Interestingly, unlike PC2-null mice, which are viable, 7B2-null mutants die early in life from Cushing's disease due to corticotropin ('ACTH') hypersecretion by the neurointermediate lobe, suggesting a possible involvement of 7B2 in secretory granule formation and in secretion regulation. The mechanism of this regulation is yet to be elucidated. 7B2 has been shown to be a good marker of several neuroendocrine cell dysfunctions in humans. The possibility that anomalies in its structure and expression could be aetiological causes of some of these dysfunctions warrants investigation. PMID:11439082

  10. Precipitation method for barium metaborate (BaB2O4) synthesis from borax solution

    NASA Astrophysics Data System (ADS)

    Akşener, Eymen; Figen, Aysel Kantürk; Pişkin, Sabriye

    2013-12-01

    In this study, barium metaborate (BaB2O4, BMB) synthesis from the borax solution was carried out. BMB currently is used in production of ceramic glazes, luminophors, oxide cathodes as well as additives to pigments for aqueous emulsion paints and also β-BaB2O4 single crystals are the best candidate for fabrication of solid-state UV lasers operating at a wavelength of 200 nm due to excellent nonlinear optical properties. In the present study, synthesis was carried out from the borax solution (Na2B4O7ṡ10H2O, BDH) and barium chloride (BaCI2ṡ2H2O, Ba) in the glass-batch reactor with stirring. The effect of, times (5-15 min), molar ratio [stoich.ration (1.0:2.0), 1.25:2.0, 1.5:2.0, 2.5:2:0, 3.0:2.0, 3.5:2.0,4.0:2.0, 5.0:2.0] and also crystallization time (2-6 hour) on the BMB yield (%) was investigated at 80 °C reaction temperature. It is found that, BMB precipitation synthesis with 90 % yield can be performed from 0.50 molar ration (BDH:Ba), under 80 °C, 15 minute, and 6 hours crystallization time. The structural properties of BMB powders were characterized by using XRD, FT-IR and DTA-TG instrumental analysis technique.

  11. Nuclear Reactors. Revised.

    ERIC Educational Resources Information Center

    Hogerton, John F.

    This publication is one of a series of information booklets for the general public published by the United States Atomic Energy Commission. Among the topics discussed are: How Reactors Work; Reactor Design; Research, Teaching, and Materials Testing; Reactors (Research, Teaching and Materials); Production Reactors; Reactors for Electric Power…

  12. 26 CFR 1.167(b)-2 - Declining balance method.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 2 2010-04-01 2010-04-01 false Declining balance method. 1.167(b)-2 Section 1... Declining balance method. (a) Application of method. Under the declining balance method a uniform rate is... declining balance rate may be determined without resort to formula. Such rate determined under section...

  13. 26 CFR 1.167(b)-2 - Declining balance method.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 2 2014-04-01 2014-04-01 false Declining balance method. 1.167(b)-2 Section 1... Declining balance method. (a) Application of method. Under the declining balance method a uniform rate is... declining balance rate may be determined without resort to formula. Such rate determined under section...

  14. 26 CFR 1.167(b)-2 - Declining balance method.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 2 2011-04-01 2011-04-01 false Declining balance method. 1.167(b)-2 Section 1... Declining balance method. (a) Application of method. Under the declining balance method a uniform rate is... declining balance rate may be determined without resort to formula. Such rate determined under section...

  15. 26 CFR 1.167(b)-2 - Declining balance method.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 2 2013-04-01 2013-04-01 false Declining balance method. 1.167(b)-2 Section 1... Declining balance method. (a) Application of method. Under the declining balance method a uniform rate is... declining balance rate may be determined without resort to formula. Such rate determined under section...

  16. 26 CFR 1.167(b)-2 - Declining balance method.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 2 2012-04-01 2012-04-01 false Declining balance method. 1.167(b)-2 Section 1... Declining balance method. (a) Application of method. Under the declining balance method a uniform rate is... declining balance rate may be determined without resort to formula. Such rate determined under section...

  17. Hexagonal OsB2: Sintering, microstructure and mechanical properties

    DOE PAGES

    Xie, Zhilin; Lugovy, Mykola; Orlovskaya, Nina; ...

    2015-02-07

    In this study, the metastable high pressure ReB2-type hexagonal OsB2 bulk ceramics was produced by spark plasma sintering. The phase composition, microstructure, and mechanical behavior of the sintered OsB2 were studied by X-ray diffraction, optical microscopy, TEM, SEM, EDS, and nanoindentation. The produced ceramics was rather porous and contained a mixture of hexagonal (~80 wt.%) and orthorhombic (~20 wt.%) phases as identified by X-ray diffraction and EBSD analysis. Two boron-rich phases, which do not contain Os, were also identified by TEM and SEM/EDS analysis. Nanoindentation measurements yielded a hardness of 31 ± 9 GPa and Young’s modulus of 574 ±more » 112 GPa, indicating that the material is rather hard and very stiff; but, it is very prone to crack formation and propagation, which is indicative of a very brittle nature of this material. Improvements in the sintering regime are required in order to produce dense, homogeneous and single phase hexagonal OsB2 bulk ceramics.« less

  18. Yield stress anomaly in B2 FeAl

    SciTech Connect

    Yoshimi, K.; Hanada, S.; Yoo, M.H.

    1996-12-31

    The studies on yield stress anomaly of B2 FeAl single crystals are reviewed in this paper. A positive temperature dependence of yield stress, so-called yield stress anomaly, is observed in B2 FeAl in which excess vacancies are fully annealed out. Associated with the anomaly, characteristic asymmetry is found between tension and compression. While the strain-rate sensitivity is almost zero in the temperature range of the yield stress anomaly, the stress relaxation becomes significant with increasing temperature, indicating that a recovery process is thermally activated. It is ascertained by the two-surface trace analysis that slip transition from <111> direction at intermediate temperature to <100> at high temperature occurs around the peak temperature. Even at the peak temperature, in addition, operative slip vector for yielding is confirmed to be predominantly <111> by TEM. Also, it is observed that <111>-type superdislocations are frequently climb-dissociated in the temperature range of the anomaly. APB formation on {l_brace}111{r_brace} plane is energetically favorable, which is in agreement with the Flinn`s calculation for the B2 superlattice that APB energy on {l_brace}111{r_brace} plane is lower than that on {l_brace}110{r_brace} plane. Such an anisotropy of APB energy would offer specific driving force for the climb dissociation on <111> superdislocations. On the basis of the observed results, the anomalous strengthening behavior of B2 FeAl single crystals is discussed.

  19. The crystal structure of URu3B2

    NASA Astrophysics Data System (ADS)

    Rogl, Peter

    1980-09-01

    The crystal structure of URu3B2 has been determined by single crystal X-ray analysis. URu3B2 crystallizes in the trigonal space group P3bar (C131) with hexagonal lattice a = 1.09531(14), c = 0.59353 (8) nm, Z = 8. Intensity measurements were obtained from a fourcircle diffractometer. The structure was solved by Patterson methods and refined by full matrix least squares calculation. The final R-value, R = ∑ |ΔF|/∑ F0, is 0.052 for an asymetric set of 962 independent reflections (l-F0l > 2 σ (F0)). The crystal structure is a twofold superstructure (distortion-derivative) of the CeCo3B2-type cell (a = 2a', c = 2c' and thus closely related to the CaCu5 type structure. The coordination numbers of U are 2 U + 12 Ru + (6 B) and those of Ru atoms 4 U + 6 Ru + 4 B. The isolated boron atoms have tetrakaidekahedral metal coordination 6 Ru + 3 U; no boron-boron contacts occur. The structural chemistry of (Th, U, RE)Ru3B2 phases is discussed.

  20. 17 CFR 240.12b-2 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... registrant or any of its parents or subsidiaries. Business combination related shell company: The term business combination related shell company means a shell company (as defined in § 240.12b-2) that is: (1) Formed by an entity that is not a shell company solely for the purpose of changing the corporate...

  1. Nuclear reactor

    DOEpatents

    Pennell, William E.; Rowan, William J.

    1977-01-01

    A nuclear reactor in which the core components, including fuel-rod assemblies, control-rod assemblies, fertile rod-assemblies, and removable shielding assemblies, are supported by a plurality of separate inlet modular units. These units are referred to as inlet module units to distinguish them from the modules of the upper internals of the reactor. The modular units are supported, each removable independently of the others, in liners in the supporting structure for the lower internals of the reactor. The core assemblies are removably supported in integral receptacles or sockets of the modular units. The liners, units, sockets and assmblies have inlet openings for entry of the fluid. The modular units are each removably mounted in the liners with fluid seals interposed between the opening in the liner and inlet module into which the fluid enters and the upper and lower portion of the liner. Each assembly is similarly mounted in a corresponding receptacle with fluid seals interposed between the openings where the fluid enters and the lower portion of the receptacle or fitting closely in these regions. As fluid flows along each core assembly a pressure drop is produced along the fluid so that the fluid which emerges from each core assembly is at a lower pressure than the fluid which enters the core assembly. However because of the seals interposed in the mountings of the units and assemblies the pressures above and below the units and assemblies are balanced and the units are held in the liners and the assemblies are held in the receptacles by their weights as they have a higher specific gravity than the fluid. The low-pressure spaces between each module and its liner and between each core assembly and its module is vented to the low-pressure regions of the vessel to assure that fluid which leaks through the seals does not accumulate and destroy the hydraulic balance.

  2. NUCLEAR REACTORS

    DOEpatents

    Long, E.; Ashley, J.W.

    1958-12-16

    A graphite moderator structure is described for a gas-cooled nuclear reactor having a vertical orlentation wherein the structure is physically stable with regard to dlmensional changes due to Wigner growth properties of the graphite, and leakage of coolant gas along spaces in the structure is reduced. The structure is comprised of stacks of unlform right prismatic graphite blocks positioned in layers extending in the direction of the lengths of the blocks, the adjacent end faces of the blocks being separated by pairs of tiles. The blocks and tiles have central bores which are in alignment when assembled and are provided with cooperatlng keys and keyways for physical stability.

  3. REACTOR COMPONETN

    DOEpatents

    Creutz, E.C.

    1959-10-27

    A reactor fuel element comprised of a slug of fissionable material disposed in a sheath of corrosion resistantmaterial is described. The sheath is in the form of a tubular container closed at one end and is in tight-fitting engagement with the peripheral sunface of the slug. An inner cap is insented into the open end of the sheath against the slug, which end is then bent around the inner cap and welded thereto. An outer cap is then welded around its peripheny to the bent portion of the container.

  4. Photocatalytic reactor

    DOEpatents

    Bischoff, B.L.; Fain, D.E.; Stockdale, J.A.D.

    1999-01-19

    A photocatalytic reactor is described for processing selected reactants from a fluid medium comprising at least one permeable photocatalytic membrane having a photocatalytic material. The material forms an area of chemically active sites when illuminated by light at selected wavelengths. When the fluid medium is passed through the illuminated membrane, the reactants are processed at these sites separating the processed fluid from the unprocessed fluid. A light source is provided and a light transmitting means, including an optical fiber, for transmitting light from the light source to the membrane. 4 figs.

  5. Dynamics of the formation and loss of boron atoms in a H2/B2H6 microwave plasma

    NASA Astrophysics Data System (ADS)

    Duluard, C. Y.; Aubert, X.; Sadeghi, N.; Gicquel, A.

    2016-09-01

    For further improvements in doped-diamond deposition technology, an understanding of the complex chemistry in H2/CH4/B2H6 plasmas is of general importance. In this context, a H2/B2H6 plasma ignited by microwave power in a near resonant cavity at high pressure (100-200 mbar) is studied to measure the B-atom density in the ground state. The discharge is ignited in the gas mixture (0-135 ppm B2H6 in H2) by a 2.45 GHz microwave generator, leading to the formation of a hemispheric plasma core, surrounded by a faint discharge halo filling the remaining reactor volume. Measurements with both laser induced fluorescence and resonant absoption with a boron hollow cathode lamp indicate that the B-atom density is higher in the halo than in the plasma core. When the absorption line-of-sight is positioned in the halo, the absorption is so strong that the upper detection limit is reached. To understand the mechanisms of creation and loss of boron atoms, time-resolved absorption measurements have been carried out in a pulsed plasma regime (10 Hz, duty cycle 50%). The study focuses on the influence of the total pressure, the partial pressure of B2H6, as well as the source power, on the growth and decay rates of boron atoms when the plasma is turned off.

  6. Sintering process and critical current density of low activation Mg11B2 superconductors from low temperature to high temperature

    NASA Astrophysics Data System (ADS)

    Cheng, Fang; Liu, Yongchang; Ma, Zongqing; Shahriar Al Hossain, Md; Somer, M.

    2016-08-01

    As the "low activation" superconductor, Mg11B2 has a potential application in superconducting coils for fusion reactor. In present work, the sintering process and critical current density of low activation Mg11B2 superconductors were systemically studied from low temperature to high temperature. It was found that the Jc and Hirr values of Mg11B2 bulks in present work are both obviously higher than that of those samples prepared in previous studies. Furthermore, the low-temperature sintered samples exhibit better Jc performance at high fields than the high-temperature sintered samples, due to strong grain boundaries pinning. On the other hand, the high-temperature sintered samples have higher Jc at low fields compared to low-temperature sintered samples, mainly owing to their better crystallinity and grain connectivity. The highest Jc value (2.20 ×105 A cm-2 at 20 K, self-field) is obtained in the Mg11B2 sample sintered at 850 °C for 45 min.

  7. Hybrid adsorptive membrane reactor

    NASA Technical Reports Server (NTRS)

    Tsotsis, Theodore T. (Inventor); Sahimi, Muhammad (Inventor); Fayyaz-Najafi, Babak (Inventor); Harale, Aadesh (Inventor); Park, Byoung-Gi (Inventor); Liu, Paul K. T. (Inventor)

    2011-01-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  8. Hybrid adsorptive membrane reactor

    SciTech Connect

    Tsotsis, Theodore T.; Sahimi, Muhammad; Fayyaz-Najafi, Babak; Harale, Aadesh; Park, Byoung-Gi; Liu, Paul K. T.

    2011-03-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  9. Control Means for Reactor

    DOEpatents

    Manley, J. H.

    1961-06-27

    An apparatus for controlling a nuclear reactor includes a tank just below the reactor, tubes extending from the tank into the reactor, and a thermally expansible liquid neutron absorbent material in the tank. The liquid in the tank is exposed to a beam of neutrons from the reactor which heats the liquid causing it to expand into the reactor when the neutron flux in the reactor rises above a predetermincd danger point. Boron triamine may be used for this purpose.

  10. Substitution Effects on MgB2 Superconductivity

    NASA Astrophysics Data System (ADS)

    Liu, Juan; Zhao, Yuan; Yi, Lin

    2008-02-01

    With the help of supercell method, the first-principle calculations were performed for the study of doping crystal Mg1-xAlxB2 and Mg(B1-yCy)2. Analyzing the variations of the charge distribution and the partial densities of states, we found that the compounds with doping Al to MgB2 compound and/or replacing boron by carbon exhibit new covalent bond effects and unexpected electronic properties, related to superconductivity. The study of the density of states indicates that superconductivity decreases with the increase of Al fraction and carbon concentration. There exists a transition of superconductor to non-superconductor with the change of Al doping fraction. The substitution of boron by carbon results in the decrease of the transition temperature since the decrease of the electron concentration and the lattice constant. The theoretical predictions agree with experimental observations.

  11. Active Protection of an MgB2 Test Coil

    PubMed Central

    Park, Dong Keun; Hahn, Seungyong; Bascuñán, Juan; Iwasa, Yukikazu

    2011-01-01

    This paper presents results of a study, experimental and computational, of a detect-and-activate-the-heater protection technique applied to a magnesium diboride (MgB2) test coil operated in semi-persistent mode. The test coil with a winding ID of 25 cm and wound with ~500-m long reacted MgB2 wire was operated at 4.2 K immersed in a bath of liquid helium. In this active technique, upon the initiation of a “hot spot” of a length ~10 cm, induced by a “quench heater,” a “protection heater” (PH) of ~600-cm long planted within the test coil is activated. The normal zone created by the PH is large enough to absorb the test coil’s entire initial stored energy and still keeps the peak temperature within the winding below ~260 K. PMID:22081754

  12. Attempts at doping indium in MgB2

    NASA Astrophysics Data System (ADS)

    Grivel, J.-C.

    2016-12-01

    Indium (In) doped MgB2 polycrystalline samples were prepared by solid-liquid phase reaction in Ar. After reaction at 800 °C, less than 1 at.% Mg was replaced by In in the MgB2 phase, without significant influence on its lattice parameters and only a slight decrease of its superconducting transition temperature. For all studied In concentrations in the nominal composition, the formation of InMg was evidenced by X-ray diffraction. The critical current density and accommodation field of the wires are decreased in the samples containing In. The flux pinning mechanism can be described by surface pinning in both the doped and undoped samples.

  13. Local Strain Development and Property Variability in B2 Intermetallics

    DTIC Science & Technology

    2005-09-19

    COVERED (From - To) 19092005 Final Report 15 Jan 2001 - 30 Apr 2005 4 . TITLE AND SUBTITLE 5a. CONTRACT NUMBER Local Strain Development and Property...Variability in B2 Intermetallics 5b. GRANT NUMBER F49620-01-1-0159 5c. PROGRAM ELEMENT NUMBER 6 . AUTHOR(S) 5d. PROJECT NUMBER Professor Tresa M. Pollock 5e... 4 3.0 The Strain Mapping Technique .............................................. 4 4.0 Intermetallic

  14. Novel Drugs that Target ErbB2

    DTIC Science & Technology

    2011-05-01

    INTRODUCTION Betulinic acid (BA) is relatively non-toxic in rodent studies and highly effective against melanoma in both in vivo and in vitro assays (1...within a month. • An abstract entitled " Betulinic Acid Inhibits BT474 and SKBR3 Breast Cancer Cell Growth by Targeting Sp Proteins and ErbB2" was...presented at the annual meeting of the Society of Toxicology in Salt Lake City, UT in March, 2010. CONCLUSIONS Betulinic acid is a

  15. Regulation of bradykinin B2-receptor expression by oestrogen

    PubMed Central

    Madeddu, Paolo; Emanueli, Costanza; Varoni, Maria Vittoria; Demontis, Maria Piera; Anania, Vittorio; Gorioso, Nicola; Chao, Julie

    1997-01-01

    Tissue kallikrein is overexpressed in the kidney of female rats, this sexual dimorphism being associated with a greater effect of early blockade of bradykinin B2-receptors on female blood pressure phenotype. We evaluated the effect of ovariectomy and oestradiol benzoate (50 μg kg−1 every two days for two weeks) on the vasodepressor response to intra-arterial injection of bradykinin (150–900 ng kg−1) and on the expression of bradykinin B2-receptors.Ovariectomy reduced the magnitude of the vasodepressor response to bradykinin and unmasked a secondary vasopressor effect. Oestrogen replacement restored the vasodepressor response to bradykinin in ovariectomized rats.The vasodepressor responses to sodium nitroprusside (3–18 μg kg−1), acetylcholine (30–600 ng kg−1), desArg9-bradykinin (150–900 ng kg−1) or prostaglandin E2 (30–600 ng kg−1) were significantly reduced by ovariectomy. Oestrogen restored to normal the responses to desArg9-bradykinin, acetylcholine and prostaglandin E2, but not that to sodium nitroprusside.B2-receptor mRNA levels were decreased by ovariectomy in the aorta and kidney and they were restored to normal levels by oestrogen. Neither ovariectomy nor oestradiol affected receptor expression in the heart and uterus.These results indicate that oestrogen regulates B2-receptor gene expression and function. Since kinins exert a cardiovascular protective action, reduction in their vasodilator activity after menopause might contribute to the increased risk of pathological cardiovascular events. Conversely, the cardioprotective effects of oestrogen replacement might be, at least in part, mediated by activation of the kallikrein-kinin system. PMID:9283715

  16. Photophysics and photochemistry of aflatoxins B1 and B2.

    PubMed

    Netto-Ferreira, J C; Heyne, B; Scaiano, J C

    2011-10-01

    Aflatoxins are mycotoxins produced by fungi of the genus Aspergillus, which is widely spread in the tropics and subtropics. To date, aflatoxin phototoxicity has been recognized, but the mechanism responsible for this phototoxicity has not been fully characterized. In the present paper, nanosecond laser flash photolysis studies allowed us to elucidate the photochemical processes undergone by two mycotoxins, namely aflatoxin B(1) and B(2), upon UV irradiation. In brief, photolysis (308 nm) of the aflatoxins leads to intersystem crossing, giving rise to their triplet excited state. The triplet state can readily be quenched by indole and hydroquinone, and also by molecular oxygen yielding singlet oxygen (singlet oxygen quantum yields of 0.51 and 0.59 were found for aflatoxin B(1) and B(2), respectively). In addition, our data indicate the ability of the two aflatoxins to photoionize upon 248 nm excitation. The photoionization quantum yield for aflatoxin B(1) and B(2) have been estimated to be 0.11 and 0.29, respectively.

  17. Modernization of B-2 Data, Video, and Control Systems Infrastructure

    NASA Technical Reports Server (NTRS)

    Cmar, Mark D.; Maloney, Christian T.; Butala, Vishal D.

    2012-01-01

    The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) Plum Brook Station (PBS) Spacecraft Propulsion Research Facility, commonly referred to as B-2, is NASA s third largest thermal-vacuum facility with propellant systems capability. B-2 has completed a modernization effort of its facility legacy data, video and control systems infrastructure to accommodate modern integrated testing and Information Technology (IT) Security requirements. Integrated systems tests have been conducted to demonstrate the new data, video and control systems functionality and capability. Discrete analog signal conditioners have been replaced by new programmable, signal processing hardware that is integrated with the data system. This integration supports automated calibration and verification of the analog subsystem. Modern measurement systems analysis (MSA) tools are being developed to help verify system health and measurement integrity. Legacy hard wired digital data systems have been replaced by distributed Fibre Channel (FC) network connected digitizers where high speed sampling rates have increased to 256,000 samples per second. Several analog video cameras have been replaced by digital image and storage systems. Hard-wired analog control systems have been replaced by Programmable Logic Controllers (PLC), fiber optic networks (FON) infrastructure and human machine interface (HMI) operator screens. New modern IT Security procedures and schemes have been employed to control data access and process control flows. Due to the nature of testing possible at B-2, flexibility and configurability of systems has been central to the architecture during modernization.

  18. Agent-based services for B2B electronic commerce

    NASA Astrophysics Data System (ADS)

    Fong, Elizabeth; Ivezic, Nenad; Rhodes, Tom; Peng, Yun

    2000-12-01

    The potential of agent-based systems has not been realized yet, in part, because of the lack of understanding of how the agent technology supports industrial needs and emerging standards. The area of business-to-business electronic commerce (b2b e-commerce) is one of the most rapidly developing sectors of industry with huge impact on manufacturing practices. In this paper, we investigate the current state of agent technology and the feasibility of applying agent-based computing to b2b e-commerce in the circuit board manufacturing sector. We identify critical tasks and opportunities in the b2b e-commerce area where agent-based services can best be deployed. We describe an implemented agent-based prototype system to facilitate the bidding process for printed circuit board manufacturing and assembly. These activities are taking place within the Internet Commerce for Manufacturing (ICM) project, the NIST- sponsored project working with industry to create an environment where small manufacturers of mechanical and electronic components may participate competitively in virtual enterprises that manufacture printed circuit assemblies.

  19. Fine-Filament MgB2 Superconductor Wire

    NASA Technical Reports Server (NTRS)

    Cantu, Sherrie

    2015-01-01

    Hyper Tech Research, Inc., has developed fine-filament magnesium diboride (MgB2) superconductor wire for motors and generators used in turboelectric aircraft propulsion systems. In Phase I of the project, Hyper Tech demonstrated that MgB2 multifilament wires (<10 micrometers) could reduce alternating current (AC) losses that occur due to hysteresis, eddy currents, and coupling losses. The company refined a manufacturing method that incorporates a magnesium-infiltration process and provides a tenfold enhancement in critical current density over wire made by a conventional method involving magnesium-boron powder mixtures. Hyper Tech also improved its wire-drawing capability to fabricate fine multifilament strands. In Phase II, the company developed, manufactured, and tested the wire for superconductor and engineering current density and AC losses. Hyper Tech also fabricated MgB2 rotor coil packs for a superconducting generator. The ultimate goal is to enable low-cost, round, lightweight, low-AC-loss superconductors for motor and generator stator coils operating at 25 K in next-generation turboelectric aircraft propulsion systems.

  20. Strength anomaly in B2 FeAl single crystals

    SciTech Connect

    Yoshimi, K.; Hanada, S.; Yoo, M.H.; Matsumoto, N.

    1994-12-31

    Strength and deformation microstructure of B2 Fe-39 and 48%Al single crystals (composition given in atomic percent), which were fully annealed to remove frozen-in vacancies, have been investigated at temperatures between room temperature and 1073K. The hardness of as-homogenized Fe-48Al is higher than that of as-homogenized Fe-39Al while after additional annealing at 698K the hardness of Fe-48Al becomes lower than that of Fe-39Al. Fe-39Al single crystals slowly cooled after homogenizing at a high temperature were deformed in compression as a function of temperature and crystal orientation. A peak of yield strength appears around 0.5T{sub m} (T{sub m} = melting temperature). The orientation dependence of the critical resolved shear stress does not obey Schmid`s law even at room temperature and is quite different from that of b.c.c. metals and B2 intermetallics at low temperatures. At the peak temperature slip transition from <111>-type to <001>-type is found to occur macroscopically and microscopically, while it is observed in TEM that some of the [111] dislocations decompose into [101] and [010] on the (1096I) plane below the peak temperature. The physical sources for the positive temperature dependence of yield stress of B2 FeAl are discussed based on the obtained results.

  1. Modernization of B-2 Data, Video, and Control Systems Infrastructure

    NASA Technical Reports Server (NTRS)

    Cmar, Mark D.; Maloney, Christian T.; Butala, Vishal D.

    2012-01-01

    The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) Plum Brook Station (PBS) Spacecraft Propulsion Research Facility, commonly referred to as B-2, is NASA's third largest thermal-vacuum facility with propellant systems capability. B-2 has completed a modernization effort of its facility legacy data, video and control systems infrastructure to accommodate modern integrated testing and Information Technology (IT) Security requirements. Integrated systems tests have been conducted to demonstrate the new data, video and control systems functionality and capability. Discrete analog signal conditioners have been replaced by new programmable, signal processing hardware that is integrated with the data system. This integration supports automated calibration and verification of the analog subsystem. Modern measurement systems analysis (MSA) tools are being developed to help verify system health and measurement integrity. Legacy hard wired digital data systems have been replaced by distributed Fibre Channel (FC) network connected digitizers where high speed sampling rates have increased to 256,000 samples per second. Several analog video cameras have been replaced by digital image and storage systems. Hard-wired analog control systems have been replaced by Programmable Logic Controllers (PLC), fiber optic networks (FON) infrastructure and human machine interface (HMI) operator screens. New modern IT Security procedures and schemes have been employed to control data access and process control flows. Due to the nature of testing possible at B-2, flexibility and configurability of systems has been central to the architecture during modernization.

  2. NEUTRONIC REACTOR

    DOEpatents

    Daniels, F.

    1962-12-18

    A power plant is described comprising a turbine and employing round cylindrical fuel rods formed of BeO and UO/sub 2/ and stacks of hexagonal moderator blocks of BeO provided with passages that loosely receive the fuel rods so that coolant may flow through the passages over the fuels to remove heat. The coolant may be helium or steam and fiows through at least one more heat exchanger for producing vapor from a body of fluid separate from the coolant, which fluid is to drive the turbine for generating electricity. By this arrangement the turbine and directly associated parts are free of particles and radiations emanating from the reactor. (AEC)

  3. NEUTRONIC REACTOR

    DOEpatents

    McGarry, R.J.

    1958-04-22

    Fluid-cooled nuclear reactors of the type that utilize finned uranium fuel elements disposed in coolant channels in a moderater are described. The coolant channels are provided with removable bushings composed of a non- fissionable material. The interior walls of the bushings have a plurality of spaced, longtudinal ribs separated by grooves which receive the fins on the fuel elements. The lands between the grooves are spaced from the fuel elements to form flow passages, and the size of the now passages progressively decreases as the dlstance from the center of the core increases for the purpose of producing a greater cooling effect at the center to maintain a uniform temperature throughout the core.

  4. NEUTRONIC REACTOR

    DOEpatents

    Stewart, H.B.

    1958-12-23

    A nuclear reactor of the type speclfically designed for the irradiation of materials is discussed. In this design a central cyllndrical core of moderating material ls surrounded by an active portlon comprlsed of an annular tank contalning fissionable material immersed ln a liquid moderator. The active portion ls ln turn surrounded by a reflector, and a well ls provided in the center of the core to accommodate the materlals to be irradiated. The over-all dimensions of the core ln at least one plane are equal to or greater than twice the effective slowing down length and equal to or less than twlce the effective diffuslon length for neutrons in the core materials.

  5. Nuclear reactor

    DOEpatents

    Yant, Howard W.; Stinebiser, Karl W.; Anzur, Gregory C.

    1977-01-01

    A nuclear reactor, particularly a liquid-metal breeder reactor, whose upper internals include outlet modules for channeling the liquid-metal coolant from selected areas of the outlet of the core vertically to the outlet plenum. The modules are composed of a highly-refractory, high corrosion-resistant alloy, for example, INCONEL-718. Each module is disposed to confine and channel generally vertically the coolant emitted from a subplurality of core-component assemblies. Each module has a grid with openings, each opening disposed to receive the coolant from an assembly of the subplurality. The grid in addition serves as a holdown for the assemblies of the corresponding subplurality preventing their excessive ejection upwardly from the core. In the region directly over the core the outlet modules are of such peripheral form that they nest forming a continuum over the core-component assemblies whose outlet coolant they confine. Each subassembly includes a chimney which confines the coolant emitted by its corresponding subassemblies to generally vertical flow between the outlet of the core and the outlet plenum. Each subplurality of assemblies whose emitted coolant is confined by an outlet module includes assemblies which emit lower-temperature coolant, for example, a control-rod assembly, or fertile assemblies, and assemblies which emit coolant of substantially higher temperature, for example, fuel-rod assemblies. The coolants of different temperatures are mixed in the chimneys reducing the effect of stripping (hot-cold temperature fluctuations) on the remainder of the upper internals which are composed typically of AISI-304 or AISI-316 stainless steel.

  6. Reactor and method of operation

    DOEpatents

    Wheeler, John A.

    1976-08-10

    A nuclear reactor having a flattened reactor activity curve across the reactor includes fuel extending over a lesser portion of the fuel channels in the central portion of the reactor than in the remainder of the reactor.

  7. High temperature behavior of B2-based ruthenium aluminide systems

    NASA Astrophysics Data System (ADS)

    Cao, Fang

    Ru-modified NiAl-based bond coats have the potential to improve the durability of Superalloy-Thermal Barrier Coating systems (TBCs) for advanced gas turbine engines. A fundamental understanding of the high temperature mechanical behavior across the Ni-Al-Ru B2 phase field can provide direction for the development of these new bond coats for TBCs. The purpose of this study has been to describe the fundamental processes of creep deformation in single phase B2 Ru-Al-Ni ternary alloys which would form the basis for the bond coats. To accomplish this, five ternary alloys with compositions located within the B2 field across the NiAl-RuAl phase region were fabricated and investigated. Special emphasis was placed on characterizing creep deformation and describing the operative creep mechanisms in these alloys. At room temperature, brittle failure was observed in the Ni-rich alloys in compression, while improved strength and ductility were displayed in two Ru-rich ternary alloys at temperatures up to 700°C. Exceptional creep strength was observed in these alloys, as compared to other high melting temperature B2 intermetallics. A continuous increase of the melting temperature and creep resistance with the increasing of the Ru/Ni ratio in these alloys was observed. Post-creep dislocation analyses identified the presence of <100> and <110> edge dislocations in the Ni-rich alloys, while uniformly distributed jogged <100> screw dislocations predominated in the Ru-rich ternary alloys. A transition of the creep mechanism from viscous glide controlled to jogged screw motion in these Ru-Al-Ni ternary B2 alloys with increasing Ru/Ni ratio is demonstrated by the characteristics of the creep deformation process, stress change creep tests, post-creep dislocation analyses, and numerical modeling. Additionally, the knowledge of the cyclic oxidation behavior of ruthenium aluminide-based alloy is essential, as many high-temperature applications for which this intermetallic might be

  8. Fractographic Analysis of HfB2-SiC and ZrB2-SiC Composites

    NASA Technical Reports Server (NTRS)

    Mecholsky, J.J., Jr.; Ellerby, D. T.; Johnson, S. M.; Stackpoole, M. M.; Loehman, R. E.; Arnold, Jim (Technical Monitor)

    2001-01-01

    Hafnium diboride-silicon carbide and zirconium diboride-silicon carbide composites are potential materials for high temperature leading edge applications on reusable launch vehicles. In order to establish material constants necessary for evaluation of in-situ fracture, bars fractured in four point flexure were examined using fractographic principles. The fracture toughness was determined from measurements of the critical crack sizes and the strength values, and the crack branching constants were established to use in forensic fractography of materials for future flight applications. The fracture toughnesses range from about 13 MPam (sup 1/2) at room temperature to about 6 MPam (sup 1/2) at 1400 C for ZrB2-SiC composites and from about 11 MPam (sup 1/2) at room temperature to about 4 MPam (sup 1/2) at 1400 C for HfB2-SiC composites.

  9. Reactor safety method

    DOEpatents

    Vachon, Lawrence J.

    1980-03-11

    This invention relates to safety means for preventing a gas cooled nuclear reactor from attaining criticality prior to start up in the event the reactor core is immersed in hydrogenous liquid. This is accomplished by coating the inside surface of the reactor coolant channels with a neutral absorbing material that will vaporize at the reactor's operating temperature.

  10. Physical property characterization of bulk MgB2 superconductor

    NASA Astrophysics Data System (ADS)

    Awana, V. P. S.; Vajpayee, A.; Mudgel, M.; Ganesan, V.; Awasthi, A. M.; Bhalla, G. L.; Kishan, H.

    2008-04-01

    We report synthesis, structure/micro-structure, resistivity under magnetic field [ρ(T)H], Raman spectra, thermoelectric power S(T), thermal conductivity κ(T), and magnetization of ambient pressure argon annealed polycrystalline bulk samples of MgB2, processed under identical conditions. The compound crystallizes in hexagonal structure with space group P6/mmm. Transmission electron microscopy ( TEM) reveals electron micrographs showing various types of defect features along with the presence of 3 4 nm thick amorphous layers forming the grain boundaries of otherwise crystalline MgB2. Raman spectra of the compound at room temperature exhibited characteristic phonon peak at 600 cm-1. Superconductivity is observed at 37.2 K by magnetic susceptibility χ(T), resistivity ρ(T), thermoelectric power S(T), and thermal conductivity κ(T) measurements. The power law fitting of ρ(T) give rise to Debye temperature (ΘD) at 1400 K which is found consistent with the theoretical fitting of S(T), exhibiting Θ D of 1410 K and carrier density of 3.81 × 1028/m3. Thermal conductivity κ(T) shows a jump at 38 K, i.e., at Tc, which was missing in some earlier reports. Critical current density (Jc) of up to 105 A/cm2 in 1 2 T (Tesla) fields at temperatures (T) of up to 10 K is seen from magnetization measurements. The irreversibility field, defined as the field related to merging of M(H) loops is found to be 78, 68 and 42 kOe at 4, 10 and 20 K respectively. The superconducting performance parameters viz. irreversibility field (Hirr) and critical current density Jc(H) of the studied MgB2 are improved profoundly with addition of nano-SiC and nano-diamond. The physical property parameters measured for polycrystalline MgB2 are compared with earlier reports and a consolidated insight of various physical properties is presented.

  11. Andreev reflections on a MgB2 superconductor

    NASA Astrophysics Data System (ADS)

    Aswal, D. K.; Sen, Shashwati; Gadkari, S. C.; Singh, Ajay; Gupta, S. K.; Gupta, L. C.; Bajpai, A.; Nigam, A. K.

    2002-07-01

    An Andreev-reflection study of MgB2/Ag planar junctions as a function of temperature and magnetic field is reported. The differential resistance (dV/dI) versus voltage (V) characteristics exhibited a distinct double minimum feature. This, together with a comparison of Blonder-Tinkham-Klapwijk theory of isotropic superconductor, indicates that data are not consistent with the weak-coupling BCS theory. This is further supported by unusual temperature and magnetic-field dependence of the tunneling characteristics. The results are discussed using various existing theories.

  12. NIR flaring of the blazar B2 0619+33

    NASA Astrophysics Data System (ADS)

    Carrasco, L.; Carramiñana, A.; Recillas, E.; Porras, A.; Mayya, D. Y.; Escobedo, G.

    2010-09-01

    We report on our recent observation of the blazar B2 0619+33 also known as GB6 J0622+3326 with the CANICA NIR camera on the 2.1m telescope at the Observatorio Astrofísico Guillermo Haro, located in Cananea, Mexico. On September 11th, 2010 (JD24555450.98694), we found this source to be in outburst. On this date the source was found to have a flux corresponding to H = 14.223 +/- 0.05. The source was not detected by the 2mass all sky survey.

  13. A new NIR Flare of B2 0619+33

    NASA Astrophysics Data System (ADS)

    Carrasco, L.; Carraminana, A.; Porras, A.; Recillas, E.; Mayya, D. Y.; Escobedo, G.

    2011-04-01

    We report on our recent observation of the blazar B2 0619+33 also known as GB6 J0622+3326 with the CANICA NIR camera on the 2.1m telescope at the Observatorio Astrofisico Guillermo Haro, located in Cananea, Mexico. On April 22nd, 2011 (JD24555673.635370), we found this source to be in outburst. On this date the source was found to have a flux corresponding to H = 15.328 ± 0.08. The source was not detected by the 2mass all sky survey.

  14. Site Occupancy of Ternary Additions to B2 Alloys

    NASA Technical Reports Server (NTRS)

    Bozzolo, Guillermo H.; Noebe, Ronald D.; Amador, Carlos

    2002-01-01

    In this broad-based survey study, the substitutional site preference of ternary alloying additions to B2 compounds (stable at room temperature and 50/50 composition) is determined using the Bozzolo-Ferrante-Smith (BFS) method for alloys. The method is applied to Ni, Al, Ti, Cr, Cu, Co, Fe, Ta, Hf, Mo, Nb, W, V and Ru additions to NiAl, FeAl, CoAl, CoFe, CoHf, CoTi, FeTi, RuAl, RuSi, RuHf, RuTi, and RuZr. The results are compared, when available, to experimental data and other theoretical results.

  15. Nuclear reactor

    DOEpatents

    Thomson, Wallace B.

    2004-03-16

    A nuclear reactor comprising a cylindrical pressure vessel, an elongated annular core centrally disposed within and spaced from the pressure vessel, and a plurality of ducts disposed longitudinally of the pressure vessel about the periphery thereof, said core comprising an annular active portion, an annular reflector just inside the active portion, and an annular reflector just outside the active a portion, said annular active portion comprising rectangular slab, porous fuel elements radially disposed around the inner reflector and extending the length of the active portion, wedge-shaped, porous moderator elements disposed adjacent one face of each fuel element and extending the length of the fuel element, the fuel and moderator elements being oriented so that the fuel elements face each other and the moderator elements do likewise, adjacent moderator elements being spaced to provide air inlet channels, and adjacent fuel elements being spaced to provide air outlet channels which communicate with the interior of the peripheral ducts, and means for introducing air into the air inlet channels which passes through the porous moderator elements and porous fuel elements to the outlet channel.

  16. Low-noise THz MgB2 Josephson mixer

    NASA Astrophysics Data System (ADS)

    Cunnane, Daniel; Kawamura, Jonathan H.; Acharya, Narendra; Wolak, Matthäus A.; Xi, X. X.; Karasik, Boris S.

    2016-09-01

    The potential applications for high frequency operation of the Josephson effect in MgB2 include THz mixers, direct detectors, and digital circuits. Here we report on MgB2 weak links which exhibit the Josephson behavior up to almost 2 THz and using them for low-noise heterodyne detection of THz radiation. The devices are made from epitaxial film grown in the c-axis direction by the hybrid physical-chemical vapor deposition method. The current in the junctions travels parallel to the surface of the film, thus making possible a large contribution of the quasi-two-dimensional σ-gap in transport across the weak link. These devices are connected to a planar spiral antenna with a dielectric substrate lens to facilitate coupling to free-space radiation for use as a detector. The IcRn product of the junction is 5.25 mV, giving confirmation of a large gap parameter. The sensitivity of the mixer was measured from 0.6 THz to 1.9 THz. At a bath temperature of over 20 K, a mixer noise temperature less than 2000 K (DSB) was measured near 0.6 THz.

  17. Characterization of MgB2 Superconducting Hot Electron Bolometers

    NASA Technical Reports Server (NTRS)

    Cunnane, D.; Kawamura, J. H.; Wolak, M. A.; Acharya, N.; Tan, T.; Xi, X. X.; Karasik, B. S.

    2014-01-01

    Hot-Electron Bolometer (HEB) mixers have proven to be the best tool for high-resolution spectroscopy at the Terahertz frequencies. However, the current state of the art NbN mixers suffer from a small intermediate frequency (IF) bandwidth as well as a low operating temperature. MgB2 is a promising material for HEB mixer technology in view of its high critical temperature and fast thermal relaxation allowing for a large IF bandwidth. In this work, we have fabricated and characterized thin-film (approximately 15 nanometers) MgB2-based spiral antenna-coupled HEB mixers on SiC substrate. We achieved the IF bandwidth greater than 8 gigahertz at 25 degrees Kelvin and the device noise temperature less than 4000 degrees Kelvin at 9 degrees Kelvin using a 600 gigahertz source. Using temperature dependencies of the radiation power dissipated in the device we have identified the optical loss in the integrated microantenna responsible as a cause of the limited sensitivity of the current mixer devices. From the analysis of the current-voltage (IV) characteristics, we have derived the effective thermal conductance of the mixer device and estimated the required local oscillator power in an optimized device to be approximately 1 microwatts.

  18. B2FH, the Cosmic Microwave Background and Cosmology*

    NASA Astrophysics Data System (ADS)

    Burbidge, G.

    In this talk I shall start by describing how we set about and carried out the work that led to the publication of Burbidge et al. (1957, hereafter B2FH). I then shall try and relate this work and the circumstances that surrounded it to the larger problem of the origin and formation of the universe. Here it is necessary to look back at the way that ideas developed and how, in many situations, astronomers went astray. Of course this is a personal view, though I very strongly believe that if he were still here, it is the approach that Fred Hoyle would take. I start by describing the problems originally encountered by Gamow and his associates in trying to decide where the helium was made. This leads me to a modern discussion of the origin of 2D, 3He, 4He and 7Li, originally described by B2FH as due to the x-process. While it is generally argued, following Gamow, Alpher, and Herman, that these isotopes were synthesised in a big bang I shall show that it is equally likely that these isotopes were made in active galactic nuclei, as was the cosmic microwave background (CMB), in a cyclic universe model. The key piece of observational evidence is that the amount of energy released in the conversion of hydrogen to helium in the universe is very close to the energy carried by the CMB, namely ~4.5 × 10-13 erg cm-3.

  19. Analysis of the Defect Structure of B2 Feal Alloys

    NASA Technical Reports Server (NTRS)

    Bozzolo, Guillermo; Ferrante, John; Noebe, Ronald D.; Amador, Carlos

    1995-01-01

    The Bozzolo, Ferrante and Smith (BFS) method for alloys is applied to the study of the defect structure of B2 FeAI alloys. First-principles Linear Muffin Tin Orbital calculations are used to determine the input parameters to the BFS method used in this work. The calculations successfully determine the phase field of the B2 structure, as well as the dependence with composition of the lattice parameter. Finally, the method is used to perform 'static' simulations where instead of determining the ground state configuration of the alloy with a certain concentration of vacancies, a large number of candidate ordered structures are studied and compared, in order to determine not only the lowest energy configurations but other possible metastable states as well. The results provide a description of the defect structure consistent with available experimental data. The simplicity of the BFS method also allows for a simple explanation of some of the essential features found in the concentration dependence of the heat of formation, lattice parameter and the defect structure.

  20. The rat ErbB2 tyrosine kinase receptor produced in plants is immunogenic in mice and confers protective immunity against ErbB2(+) mammary cancer.

    PubMed

    Matić, Slavica; Quaglino, Elena; Arata, Lucia; Riccardo, Federica; Pegoraro, Mattia; Vallino, Marta; Cavallo, Federica; Noris, Emanuela

    2016-01-01

    The rat ErbB2 (rErbB2) protein is a 185-kDa glycoprotein belonging to the epidermal growth factor-related proteins (ErbB) of receptor tyrosine kinases. Overexpression and mutations of ErbB proteins lead to several malignancies including breast, lung, pancreatic, bladder and ovary carcinomas. ErbB2 is immunogenic and is an ideal candidate for cancer immunotherapy. We investigated the possibility of expressing the extracellular (EC) domain of rErbB2 (653 amino acids, aa) in Nicotiana benthamiana plants, testing the influence of the 23 aa transmembrane (TM) sequence on protein accumulation. Synthetic variants of the rErbB2 gene portion encoding the EC domain, optimized with a human codon usage and either linked to the full TM domain (rErbB2_TM, 676 aa), to a portion of it (rErbB2-pTM, 662 aa), or deprived of it (rErbB2_noTM, 653 aa) were cloned in the pEAQ-HT expression vector as 6X His tag fusions. All rErbB2 variants (72-74.5 kDa) were transiently expressed, but the TM was detrimental for rErbB2 EC accumulation. rERbB2_noTM was the most expressed protein; it was solubilized and purified with Nickel affinity resin. When crude soluble extracts expressing rErbB2_noTM were administered to BALB/c mice, specific rErbB2 immune responses were triggered. A potent antitumour activity was induced when vaccinated mice were challenged with syngeneic transplantable ErbB2(+) mammary carcinoma cells. To our knowledge, this is the first report of expression of rErbB2 in plants and of its efficacy in inducing a protective antitumour immune response, opening interesting perspectives for further immunological testing.

  1. Transport simulations of linear plasma generators with the B2.5-Eirene and EMC3-Eirene codes

    DOE PAGES

    Rapp, Juergen; Owen, Larry W.; Bonnin, X.; ...

    2014-12-20

    Linear plasma generators are cost effective facilities to simulate divertor plasma conditions of present and future fusion reactors. For this research, the codes B2.5-Eirene and EMC3-Eirene were extensively used for design studies of the planned Material Plasma Exposure eXperiment (MPEX). Effects on the target plasma of the gas fueling and pumping locations, heating power, device length, magnetic configuration and transport model were studied with B2.5-Eirene. Effects of tilted or vertical targets were calculated with EMC3-Eirene and showed that spreading the incident flux over a larger area leads to lower density, higher temperature and off-axis profile peaking in front of themore » target. In conclusion, the simulations indicate that with sufficient heating power MPEX can reach target plasma conditions that are similar to those expected in the ITER divertor. B2.5-Eirene simulations of the MAGPIE experiment have been carried out in order to establish an additional benchmark with experimental data from a linear device with helicon wave heating.« less

  2. Transport simulations of linear plasma generators with the B2.5-Eirene and EMC3-Eirene codes

    SciTech Connect

    Rapp, Juergen; Owen, Larry W.; Bonnin, X.; Caneses, J. F.; Canik, John M.; Corr, Cormac; Lore, J. D.

    2014-12-20

    Linear plasma generators are cost effective facilities to simulate divertor plasma conditions of present and future fusion reactors. For this research, the codes B2.5-Eirene and EMC3-Eirene were extensively used for design studies of the planned Material Plasma Exposure eXperiment (MPEX). Effects on the target plasma of the gas fueling and pumping locations, heating power, device length, magnetic configuration and transport model were studied with B2.5-Eirene. Effects of tilted or vertical targets were calculated with EMC3-Eirene and showed that spreading the incident flux over a larger area leads to lower density, higher temperature and off-axis profile peaking in front of the target. In conclusion, the simulations indicate that with sufficient heating power MPEX can reach target plasma conditions that are similar to those expected in the ITER divertor. B2.5-Eirene simulations of the MAGPIE experiment have been carried out in order to establish an additional benchmark with experimental data from a linear device with helicon wave heating.

  3. Tokamak reactor studies

    SciTech Connect

    Baker, C.C.

    1981-01-01

    This paper presents an overview of tokamak reactor studies with particular attention to commercial reactor concepts developed within the last three years. Emphasis is placed on DT fueled reactors for electricity production. A brief history of tokamak reactor studies is presented. The STARFIRE, NUWMAK, and HFCTR studies are highlighted. Recent developments that have increased the commercial attractiveness of tokamak reactor designs are discussed. These developments include smaller plant sizes, higher first wall loadings, improved maintenance concepts, steady-state operation, non-divertor particle control, and improved reactor safety features.

  4. Integrated Product and Process Data for B2B Collaboration

    SciTech Connect

    Kulvatunyou, Boonserm; Ivezic, Nenad; Jones, Albert; Wysk, Richard A.

    2003-09-01

    Collaborative development of engineered products in a business-to-business (B2B) environment will require more than just the selection of components from an on-line catalogue. It will involve the electronic exchange of product, process, and production engineering information during both design and manufacturing. While the state-of-the-practice does include a variety of ways to exchange product data electronically, it does not extend to the exchange of manufacturing process data. The reason is simple; process data is usually tied to specific manufacturing resources. These resources are not known typically at product development time. This paper proposes an approach, called an Integrated Product and Process Data (IPPD), where manufacturing process data is considered during product development. This approach replaces traditional process plans, which are resource specific, with a resource-independent process representation. Such a representation will allow a much wider collaboration among business partners and provide the necessary base for collaborative product development.

  5. Semantic ETL into i2b2 with Eureka!

    PubMed

    Post, Andrew R; Krc, Tahsin; Rathod, Himanshu; Agravat, Sanjay; Mansour, Michel; Torian, William; Saltz, Joel H

    2013-01-01

    Clinical phenotyping is an emerging research information systems capability. Research uses of electronic health record (EHR) data may require the ability to identify clinical co-morbidities and complications. Such phenotypes may not be represented directly as discrete data elements, but rather as frequency, sequential and temporal patterns in billing and clinical data. These patterns' complexity suggests the need for a robust yet flexible extract, transform and load (ETL) process that can compute them. This capability should be accessible to investigators with limited ability to engage an IT department in data management. We have developed such a system, Eureka! Clinical Analytics. It extracts data from an Excel spreadsheet, computes a broad set of phenotypes of common interest, and loads both raw and computed data into an i2b2 project. A web-based user interface allows executing and monitoring ETL processes. Eureka! is deployed at our institution and is available for deployment in the cloud.

  6. Semantic ETL into i2b2 with Eureka!

    PubMed Central

    Post, Andrew R.; Krc, Tahsin; Rathod, Himanshu; Agravat, Sanjay; Mansour, Michel; Torian, William; Saltz, Joel H.

    Clinical phenotyping is an emerging research information systems capability. Research uses of electronic health record (EHR) data may require the ability to identify clinical co-morbidities and complications. Such phenotypes may not be represented directly as discrete data elements, but rather as frequency, sequential and temporal patterns in billing and clinical data. These patterns’ complexity suggests the need for a robust yet flexible extract, transform and load (ETL) process that can compute them. This capability should be accessible to investigators with limited ability to engage an IT department in data management. We have developed such a system, Eureka! Clinical Analytics. It extracts data from an Excel spreadsheet, computes a broad set of phenotypes of common interest, and loads both raw and computed data into an i2b2 project. A web-based user interface allows executing and monitoring ETL processes. Eureka! is deployed at our institution and is available for deployment in the cloud. PMID:24303265

  7. Magnetic flux noise in MgB2 superconductor

    NASA Astrophysics Data System (ADS)

    Khare, Neeraj; Singh, D. P.; Gupta, Ajai K.

    2008-05-01

    Magnetic flux noise in MgB2 polycrystalline sample is measured using a high-TC rf-superconducting quantum interference device in the temperature range of 6-40K. A small magnetic field (˜200mG ) was applied while cooling the sample. The flux noise exhibits 1/fα type of behavior with α ˜1.0-1.3 and shows enhanced noise around 24 and 37K. The flux noise seems to originate from thermally activated vortex hopping. The large magnetic noise at 24K indicates the presence of larger density of pinning sites with energies ˜0.061eV leading to enhanced magnetic fluctuations at temperatures much below TC.

  8. Ionization delocalization and ALCHEMI of B2-ordered alloys

    SciTech Connect

    Anderson, I.M.; Bentley, J.

    1995-06-01

    Purpose of this paper is to demonstrate that the major assumption underlying the ALCHEMI formulation is justified: that the degree of ionization localization of an elemental shell can be accounted for by a linear coefficient; and to introduce a potential method, which would be applicable to B2-ordered alloys, of independently extracting the ratio of coefficients L{sub jk} necessary for delocalization correction. A Cr-doped FeAl alloy and a series of Fe-doped NiAl alloys with 0.25-12 at. % Fe were analyzed. Excellent linearity of the data substantiates the use of linear coefficients to model ionization localization. It was investigated whether the L{sub jk} acquired at a (110) systematics orientation could be accurately applied to ALCHEMI data acquired at (200).

  9. Superconductivity of MgB2: covalent bonds driven metallic.

    PubMed

    An, J M; Pickett, W E

    2001-05-07

    A series of calculations on MgB2 and related isoelectronic systems indicates that the layer of Mg2+ ions lowers the nonbonding B pi ( p(z)) bands relative to the bonding sigma ( sp(x)p(y)) bands compared to graphite, causing sigma-->pi charge transfer and sigma band doping of 0.13 holes/cell. Because of their two dimensionality the sigma bands contribute strongly to the Fermi level density of states. Calculated deformation potentials of gamma point phonons identify the B bond stretching modes as dominating the electron-phonon coupling. Superconductivity driven by sigma band holes is consistent with the report of destruction of superconductivity by doping with Al.

  10. Oxidation of ZrB2-and HfB2-Based Ultra-High Temperature Ceramics: Effects of Ta Additions

    NASA Technical Reports Server (NTRS)

    Opila, Elizabeth; Levine, Stanley; Lorinez, Jonathan

    2003-01-01

    Several compositions of ZrB2- and HfB2-based Ultra-High Temperature Ceramics (UHTC) were oxidized in stagnant air at 1627 C in ten minute cycles for times up to 100 minutes. These compositions include: ZrB2 - 20v% SiC, HfB2 - 20v% SiC, ZrB2 - 20v% SiC - 20v% TaSi2, ZrB2 - 33v% SiC, HfB2 - 20v% SiC - 20v% TaSi2, and ZrB2 - 20v% SiC - 20v% TaC. The weight change due to oxidation was recorded. The ZrB2 - 20v% SiC - 20v% TaSi2 composition was also oxidized in stagnant air at 1927 C and in an arc jet atmosphere. Samples were analyzed after oxidation by x-ray diffraction, field emission scanning electron microscopy, and energy dispersive spectroscopy to determine the reaction products and to observe the microstructure. The ZrB2 - 20v% SiC - 20v% TaSi2 showed the lowest oxidation rate at 1627 C, but performed poorly under the more extreme tests due to liquid phase formation. Effects of Ta-additions on the oxidation of the diboride-based UHTC are discussed.

  11. The conserved nhaAR operon is drastically divergent between B2 and non-B2 Escherichia coli and is involved in extra-intestinal virulence.

    PubMed

    Lescat, Mathilde; Reibel, Florence; Pintard, Coralie; Dion, Sara; Glodt, Jérémy; Gateau, Cecile; Launay, Adrien; Ledda, Alice; Cruveiller, Stephane; Cruvellier, Stephane; Tourret, Jérôme; Tenaillon, Olivier

    2014-01-01

    The Escherichia coli species is divided in phylogenetic groups that differ in their virulence and commensal distribution. Strains belonging to the B2 group are involved in extra-intestinal pathologies but also appear to be more prevalent as commensals among human occidental populations. To investigate the genetic specificities of B2 sub-group, we used 128 sequenced genomes and identified genes of the core genome that showed marked difference between B2 and non-B2 genomes. We focused on the gene and its surrounding region with the strongest divergence between B2 and non-B2, the antiporter gene nhaA. This gene is part of the nhaAR operon, which is in the core genome but flanked by mobile regions, and is involved in growth at high pH and high sodium concentrations. Consistently, we found that a panel of non-B2 strains grew faster than B2 at high pH and high sodium concentrations. However, we could not identify differences in expression of the nhaAR operon using fluorescence reporter plasmids. Furthermore, the operon deletion had no differential impact between B2 and non-B2 strains, and did not result in a fitness modification in a murine model of gut colonization. Nevertheless, sequence analysis and experiments in a murine model of septicemia revealed that recombination in nhaA among B2 strains was observed in strains with low virulence. Finally, nhaA and nhaAR operon deletions drastically decreased virulence in one B2 strain. This effect of nhaAR deletion appeared to be stronger than deletion of all pathogenicity islands. Thus, a population genetic approach allowed us to identify an operon in the core genome without strong effect in commensalism but with an important role in extra-intestinal virulence, a landmark of the B2 strains.

  12. Inhibition of ErbB-2 Mitogenic and Transforming Activity by RALT, a Mitogen-Induced Signal Transducer Which Binds to the ErbB-2 Kinase Domain†

    PubMed Central

    Fiorentino, Loredana; Pertica, Chiara; Fiorini, Monia; Talora, Claudio; Crescenzi, Marco; Castellani, Loriana; Alemà, Stefano; Benedetti, Piero; Segatto, Oreste

    2000-01-01

    The product of rat gene 33 was identified as an ErbB-2-interacting protein in a two-hybrid screen employing the ErbB-2 juxtamembrane and kinase domains as bait. This interaction was reproduced in vitro with a glutathione S-transferase fusion protein spanning positions 282 to 395 of the 459-residue gene 33 protein. Activation of ErbB-2 catalytic function was required for ErbB-2–gene 33 physical interaction in living cells, whereas ErbB-2 autophosphorylation was dispensable. Expression of gene 33 protein was absent in growth-arrested NIH 3T3 fibroblasts but was induced within 60 to 90 min of serum stimulation or activation of the ErbB-2 kinase and decreased sharply upon entry into S phase. New differentiation factor stimulation of mitogen-deprived mammary epithelial cells also caused accumulation of gene 33 protein, which could be found in a complex with ErbB-2. Overexpression of gene 33 protein in mouse fibroblasts inhibited (i) cell proliferation driven by ErbB-2 but not by serum, (ii) cell transformation induced by ErbB-2 but not by Ras or Src, and (iii) sustained activation of ERK 1 and 2 by ErbB-2 but not by serum. The gene 33 protein may convey inhibitory signals downstream to ErbB-2 by virtue of its association with SH3-containing proteins, including GRB-2, which was found to associate with gene 33 protein in living cells. These data indicate that the gene 33 protein is a feedback inhibitor of ErbB-2 mitogenic function and a suppressor of ErbB-2 oncogenic activity. We propose that the gene 33 protein be renamed with the acronym RALT (receptor-associated late transducer). PMID:11003669

  13. Inhibition of ErbB-2 mitogenic and transforming activity by RALT, a mitogen-induced signal transducer which binds to the ErbB-2 kinase domain.

    PubMed

    Fiorentino, L; Pertica, C; Fiorini, M; Talora, C; Crescenzi, M; Castellani, L; Alemà, S; Benedetti, P; Segatto, O

    2000-10-01

    The product of rat gene 33 was identified as an ErbB-2-interacting protein in a two-hybrid screen employing the ErbB-2 juxtamembrane and kinase domains as bait. This interaction was reproduced in vitro with a glutathione S-transferase fusion protein spanning positions 282 to 395 of the 459-residue gene 33 protein. Activation of ErbB-2 catalytic function was required for ErbB-2-gene 33 physical interaction in living cells, whereas ErbB-2 autophosphorylation was dispensable. Expression of gene 33 protein was absent in growth-arrested NIH 3T3 fibroblasts but was induced within 60 to 90 min of serum stimulation or activation of the ErbB-2 kinase and decreased sharply upon entry into S phase. New differentiation factor stimulation of mitogen-deprived mammary epithelial cells also caused accumulation of gene 33 protein, which could be found in a complex with ErbB-2. Overexpression of gene 33 protein in mouse fibroblasts inhibited (i) cell proliferation driven by ErbB-2 but not by serum, (ii) cell transformation induced by ErbB-2 but not by Ras or Src, and (iii) sustained activation of ERK 1 and 2 by ErbB-2 but not by serum. The gene 33 protein may convey inhibitory signals downstream to ErbB-2 by virtue of its association with SH3-containing proteins, including GRB-2, which was found to associate with gene 33 protein in living cells. These data indicate that the gene 33 protein is a feedback inhibitor of ErbB-2 mitogenic function and a suppressor of ErbB-2 oncogenic activity. We propose that the gene 33 protein be renamed with the acronym RALT (receptor-associated late transducer).

  14. Photo-activated psoralen binds the ErbB2 catalytic kinase domain, blocking ErbB2 signaling and triggering tumor cell apoptosis.

    PubMed

    Xia, Wenle; Gooden, David; Liu, Leihua; Zhao, Sumin; Soderblom, Erik J; Toone, Eric J; Beyer, Wayne F; Walder, Harold; Spector, Neil L

    2014-01-01

    Photo-activation of psoralen with UVA irradiation, referred to as PUVA, is used in the treatment of proliferative skin disorders. The anti-proliferative effects of PUVA have been largely attributed to psoralen intercalation of DNA, which upon UV treatment, triggers the formation of interstrand DNA crosslinks (ICL) that inhibit transcription and DNA replication. Here, we show that PUVA exerts antitumor effects in models of human breast cancer that overexpress the ErbB2 receptor tyrosine kinase oncogene, through a new mechanism. Independent of ICL formation, the antitumor effects of PUVA in ErbB2+ breast cancer models can instead be mediated through inhibition of ErbB2 activation and signaling. Using a mass spectroscopy-based approach, we show for the first time that photo-activated 8MOP (8-methoxypsoralen) interacts with the ErbB2 catalytic autokinase domain. Furthermore, PUVA can reverse therapeutic resistance to lapatinib and other ErbB2 targeted therapies, including resistance mediated via expression of a phosphorylated, truncated form of ErbB2 (p85(ErbB2)) that is preferentially expressed in tumor cell nuclei. Current ErbB2 targeted therapies, small molecule kinase inhibitors or antibodies, do not block the phosphorylated, activated state of p85(ErbB2). Here we show that PUVA reduced p85(ErbB2) phosphorylation leading to tumor cell apoptosis. Thus, in addition to its effects on DNA and the formation of ICL, PUVA represents a novel ErbB2 targeted therapy for the treatment of ErbB2+ breast cancers, including those that have developed resistance to other ErbB2 targeted therapies.

  15. Hybrid plasmachemical reactor

    SciTech Connect

    Lelevkin, V. M. Smirnova, Yu. G.; Tokarev, A. V.

    2015-04-15

    A hybrid plasmachemical reactor on the basis of a dielectric barrier discharge in a transformer is developed. The characteristics of the reactor as functions of the dielectric barrier discharge parameters are determined.

  16. Attrition reactor system

    SciTech Connect

    Scott, Charles D.; Davison, Brian H.

    1993-01-01

    A reactor vessel for reacting a solid particulate with a liquid reactant has a centrifugal pump in circulatory flow communication with the reactor vessel for providing particulate attrition, resulting in additional fresh surface where the reaction can occur.

  17. Attrition reactor system

    SciTech Connect

    Scott, C.D.; Davison, B.H.

    1993-09-28

    A reactor vessel for reacting a solid particulate with a liquid reactant has a centrifugal pump in circulatory flow communication with the reactor vessel for providing particulate attrition, resulting in additional fresh surface where the reaction can occur. 2 figures.

  18. NEUTRONIC REACTOR POWER PLANT

    DOEpatents

    Metcalf, H.E.

    1962-12-25

    This patent relates to a nuclear reactor power plant incorporating an air-cooled, beryllium oxide-moderated, pebble bed reactor. According to the invention means are provided for circulating a flow of air through tubes in the reactor to a turbine and for directing a sidestream of the circu1ating air through the pebble bed to remove fission products therefrom as well as assist in cooling the reactor. (AEC)

  19. Period meter for reactors

    DOEpatents

    Rusch, Gordon K.

    1976-01-06

    An improved log N amplifier type nuclear reactor period meter with reduced probability for noise-induced scrams is provided. With the reactor at low power levels a sampling circuit is provided to determine the reactor period by measuring the finite change in the amplitude of the log N amplifier output signal for a predetermined time period, while at high power levels, differentiation of the log N amplifier output signal provides an additional measure of the reactor period.

  20. Lattice Thermal Conductivity of Ultra High Temperature Ceramics (UHTC) ZrB2 and HfB2 from Atomistic Simulations

    NASA Technical Reports Server (NTRS)

    Lawson, JOhn W.; Daw, Murray S.; Bauschlicher, Charles W.

    2011-01-01

    Ultra high temperature ceramics (UHTC) including ZrB2 and HfB2 are candidate materials for applications in extreme environments because of their high melting point, good mechanical properties and reasonable oxidation resistance. Unlike many ceramics, these materials have high thermal conductivity which can be advantageous, for example, to reduce thermal shock. Recently, we developed Tersoff style interatomic potentials for both ZrB2 and HfB2 appropriate for atomistic simulations. As an application, Green-Kubo molecular dynamics simulations were performed to evaluate the lattice thermal conductivity for single crystals of ZrB2 and HfB2. The atomic mass difference in these binary compounds leads to oscillations in the time correlation function of the heat current. Results at room temperature and at elevated temperatures will be reported.

  1. NUCLEAR REACTOR CONTROL SYSTEM

    DOEpatents

    Epler, E.P.; Hanauer, S.H.; Oakes, L.C.

    1959-11-01

    A control system is described for a nuclear reactor using enriched uranium fuel of the type of the swimming pool and other heterogeneous nuclear reactors. Circuits are included for automatically removing and inserting the control rods during the course of normal operation. Appropriate safety circuits close down the nuclear reactor in the event of emergency.

  2. Efficient Silicon Reactor

    NASA Technical Reports Server (NTRS)

    Bates, H. E.; Hill, D. M.; Jewett, D. N.

    1983-01-01

    High-purity silicon efficiently produced and transferred by continuous two-cycle reactor. New reactor operates in relatively-narrow temperature rate and uses large surfaces area to minimize heat expenditure and processing time in producing silicon by hydrogen reduction of trichlorosilane. Two cycles of reactor consists of silicon production and removal.

  3. NEUTRONIC REACTOR SHIELDING

    DOEpatents

    Borst, L.B.

    1961-07-11

    A special hydrogenous concrete shielding for reactors is described. In addition to Portland cement and water, the concrete essentially comprises 30 to 60% by weight barytes aggregate for enhanced attenuation of fast neutrons. The biological shields of AEC's Oak Ridge Graphite Reactor and Materials Testing Reactor are particular embodiments.

  4. High solids fermentation reactor

    DOEpatents

    Wyman, Charles E.; Grohmann, Karel; Himmel, Michael E.; Richard, Christopher J.

    1993-01-01

    A fermentation reactor and method for fermentation of materials having greater than about 10% solids. The reactor includes a rotatable shaft along the central axis, the shaft including rods extending outwardly to mix the materials. The reactor and method are useful for anaerobic digestion of municipal solid wastes to produce methane, for production of commodity chemicals from organic materials, and for microbial fermentation processes.

  5. High solids fermentation reactor

    DOEpatents

    Wyman, Charles E.; Grohmann, Karel; Himmel, Michael E.; Richard, Christopher J.

    1993-03-02

    A fermentation reactor and method for fermentation of materials having greater than about 10% solids. The reactor includes a rotatable shaft along the central axis, the shaft including rods extending outwardly to mix the materials. The reactor and method are useful for anaerobic digestion of municipal solid wastes to produce methane, for production of commodity chemicals from organic materials, and for microbial fermentation processes.

  6. Improved vortex reactor system

    DOEpatents

    Diebold, James P.; Scahill, John W.

    1995-01-01

    An improved vortex reactor system for affecting fast pyrolysis of biomass and Refuse Derived Fuel (RDF) feed materials comprising: a vortex reactor having its axis vertically disposed in relation to a jet of a horizontally disposed steam ejector that impels feed materials from a feeder and solids from a recycle loop along with a motive gas into a top part of said reactor.

  7. Advanced Test Reactor Tour

    SciTech Connect

    Miley, Don

    2011-01-01

    The Advanced Test Reactor at Idaho National Laboratory is the foremost nuclear materials test reactor in the world. This virtual tour describes the reactor, how experiments are conducted, and how spent nuclear fuel is handled and stored. For more information about INL research, visit http://www.facebook.com/idahonationallaboratory.

  8. Advanced Test Reactor Tour

    ScienceCinema

    Miley, Don

    2016-07-12

    The Advanced Test Reactor at Idaho National Laboratory is the foremost nuclear materials test reactor in the world. This virtual tour describes the reactor, how experiments are conducted, and how spent nuclear fuel is handled and stored. For more information about INL research, visit http://www.facebook.com/idahonationallaboratory.

  9. MgB2 tunnel junctions with native or thermal oxide barriers

    NASA Astrophysics Data System (ADS)

    Singh, R. K.; Gandikota, R.; Kim, J.; Newman, N.; Rowell, J. M.

    2006-07-01

    MgB2 tunnel junctions (MgB2/barrier/MgB2) were fabricated using a native oxide grown on the bottom MgB2 film as the tunnel barrier. Such barriers therefore survive the deposition of the second electrode at 300°C, even over junction areas of ˜1mm2. Studies of such junctions and those of the type MgB2/native or thermal oxide/metal (Pb, Au, or Ag) show that tunnel barriers grown on MgB2 exhibit a wide range of barrier heights and widths.

  10. Experiences and Future Expectations towards Online Courses--An Empirical Study of the B2C-and B2B-Segments

    ERIC Educational Resources Information Center

    Krämer, Andreas; Böhrs, Sandra

    2016-01-01

    This article explores the future potential for the development of online courses. The findings are based on an empirical study with 3 sample groups: (1) B2C segment in Germany, (2) B2C segment in the United States, and (3) B2B segment (international). In the first step the status quo of the use of e-learning in general and online courses in…

  11. Solute hardening and softening effects in B2 nickel aluminides

    SciTech Connect

    Pike, L.M.; Liu, C.T.; Anderson, I.M.; Chang, Y.A.

    1998-11-01

    The effect of substitutional solute additions including Fe, Mn, and Pd on the hardness of B2-ordered NiAl alloys was investigated. The solid solution hardening behavior of intermetallics is more complex than that of typical metallic solid solutions because of complications arising from the site preference of the solute as well as the effects of the solute on the concentrations of other point defects, e.g., vacancies and anti-site defects. For this reason, care was taken to experimentally establish solute site preferences and point defect concentrations in the NiAl alloys before analyzing the hardness data. By taking these factors into account it was possible to rationalize the observed unusual hardening effects. Three distinct categories of solid solution hardening behavior were encountered. The first was hardening by the solute addition itself. This was observed in the case of Pd additions to Al-poor NiAl. However, when fe or Mn is added to Al-poor NiAl a second category is observed; these elements are seen to soften the material. The third category of behavior is observed when Fe is added to NiAl with a constant Al concentration of 50 at. %. In this case it is vacancies, rather than solute atoms, which harden the material.

  12. Effects of neutron irradiation on polycrystalline Mg11B2

    NASA Astrophysics Data System (ADS)

    Tarantini, C.; Aebersold, H. U.; Braccini, V.; Celentano, G.; Ferdeghini, C.; Ferrando, V.; Gambardella, U.; Gatti, F.; Lehmann, E.; Manfrinetti, P.; Marré, D.; Palenzona, A.; Pallecchi, I.; Sheikin, I.; Siri, A. S.; Putti, M.

    2006-04-01

    We studied the influence of the disorder introduced in polycrystalline MgB2 samples by neutron irradiation. To circumvent self-shielding effects due to the strong interaction between thermal neutrons and B10 we employed isotopically enriched B11 which contains 40 times less B10 than natural B. The comparison of electrical and structural properties of different series of samples irradiated in different neutron sources, also using Cd shields, allowed us to conclude that, despite the low B10 content, the main damage mechanisms are caused by thermal neutrons, whereas fast neutrons play a minor role. Irradiation leads to an improvement in both upper critical field and critical current density for an exposure level in the range 1-2×1018cm-2 . With increasing fluence the superconducting properties are depressed. An in-depth analysis of the critical field and current density behavior has been carried out to identify what scattering and pinning mechanisms come into play. Finally, the correlation between some characteristic lengths and the transition widths is analyzed.

  13. A Novel Stable Binary BeB2 phase

    PubMed Central

    Fan, Changzeng; Jin, Ye; Li, Jian; Dong, Xu

    2014-01-01

    Potential crystal structures of BeB2 were explored using ab initio evolutionary simulations. A new phase with a Cmcm space group was uncovered. It was determined that the Cmcm phase is mechanically and dynamically stable and has a lower enthalpy, from ambient pressure up to 13 GPa, than any previously proposed phases, as measured using first-principles calculations. The crystal structure, phonon dispersion, phase transitions, and mechanical and electronic properties of this phase were investigated. It was determined that the Cmcm phase may transform into the phase at pressures higher than 13 GPa. The band structures and density of states reveal that the Cmcm phase is metallic. In addition, the Vickers hardness was calculated using three empirical models. To explain the origin of the hardness, charge density difference maps and a Mulliken population analysis were carried out, which demonstrated that there are strong covalent interactions between B atoms. By analyzing the Crystal Orbital Hamilton Population (COHP) diagrams, it was determined that the total interaction of the Be-B bonds is stronger than that of the B-B bonds, indicating a very complex bonding feature in the new phase. It was predicted that the new Cmcm phase is nearly absent of superconductivity. PMID:25385147

  14. Lightweight MgB2 superconducting 10 MW wind generator

    NASA Astrophysics Data System (ADS)

    Marino, I.; Pujana, A.; Sarmiento, G.; Sanz, S.; Merino, J. M.; Tropeano, M.; Sun, J.; Canosa, T.

    2016-02-01

    The offshore wind market demands a higher power rate and more reliable turbines in order to optimize capital and operational costs. The state-of-the-art shows that both geared and direct-drive conventional generators are difficult to scale up to 10 MW and beyond due to their huge size and weight. Superconducting direct-drive wind generators are considered a promising solution to achieve lighter weight machines. This work presents an innovative 10 MW 8.1 rpm direct-drive partial superconducting generator using MgB2 wire for the field coils. It has a warm iron rotor configuration with the superconducting coils working at 20 K while the rotor core and the armature are at ambient temperature. A cooling system based on cryocoolers installed in the rotor extracts the heat from the superconducting coils by conduction. The generator's main parameters are compared against a permanent magnet reference machine, showing a significant weight and size reduction. The 10 MW superconducting generator concept will be experimentally validated with a small-scale magnetic machine, which has innovative components such as superconducting coils, modular cryostats and cooling systems, and will have similar size and characteristics as the 10 MW generator.

  15. Damping and modulus measurements in B2 transition metal aluminides

    NASA Technical Reports Server (NTRS)

    Harmouche, M. R.; Wolfenden, A.

    1985-01-01

    The polycrystalline intermetallic alloys FeAl (50.9 to 58.2 percent Fe), NiAl (49.2 to 55.9 percent Ni) and CoAl (48.5 to 52.3 percent Co) have the B2 structure and are of interest for high temperature applications. The PUCOT (piezoelectric ultrasonic composite oscillator technique) has been used to measure mechanical damping or internal friction and Young's modulus has been used as a function of temperature and composition for these materials. The modulus data for six CoAl alloys at temperatures up to 1300 K are presented. Examples are given of the strain amplitude dependence of internal friction for four CoAl alloys. The curves showed the break away phenomenon and are interpreted in terms of a theory dealing with the pinning of dislocation lines and their eventual break away at large strain amplitudes. The dislocation density was calculated to be about 10 to the 8th per sq m. For all the compositions (X1) of CoAl studied, a single equation could be fitted to the data.

  16. Organic Anion–Transporting Polypeptide 1b2 (Oatp1b2) Is Important for the Hepatic Uptake of Unconjugated Bile Acids: Studies in Oatp1b2-Null Mice

    PubMed Central

    Csanaky, Iván L.; Lu, Hong; Zhang, Youcai; Ogura, Kenichiro; Choudhuri, Supratim; Klaassen, Curtis D.

    2011-01-01

    The organic anion–transporting polypeptide 1b family (Oatp1b2 in rodents and OATP1B1/1B3 in humans) is liver-specific and transports various chemicals into the liver. However, the role of the Oatp1b family in the hepatic uptake of bile acids (BAs) into the liver is unknown. Therefore, in Oatp1b2-null mice, the concentrations of BAs in plasma, liver, and bile were compared with wild-type (WT) mice. It was first determined that livers of the Oatp1b2-null mice were not compensated by altered expression of other hepatic transporters. However, the messenger RNA of Cyp7a1 was 70% lower in the Oatp1b2-null mice. Increased expression of fibroblast growth factor 15 in intestines of Oatp1b2-null mice might be responsible for decreased hepatic expression of Cyp7a1 in Oatp1b2-null mice. The hepatic concentration and biliary excretion of conjugated and unconjugated BAs were essentially the same in Oatp1b2-null and WT mice. The serum concentration of taurine-conjugated BAs was essentially the same in the two genotypes. In contrast, the serum concentrations of unconjugated BAs were 3–45 times higher in Oatp1b2-null than WT mice. After intravenous administration of cholate to Oatp1b2-null mice, its clearance was 50% lower than in WT mice, but the clearance of taurocholate was similar in the two genotypes. Conclusion This study indicates that Oatp1b2 has a major role in the hepatic uptake of unconjugated BAs. PMID:20949553

  17. Reactor vessel support system

    DOEpatents

    Golden, Martin P.; Holley, John C.

    1982-01-01

    A reactor vessel support system includes a support ring at the reactor top supported through a box ring on a ledge of the reactor containment. The box ring includes an annular space in the center of its cross-section to reduce heat flow and is keyed to the support ledge to transmit seismic forces from the reactor vessel to the containment structure. A coolant channel is provided at the outside circumference of the support ring to supply coolant gas through the keyways to channels between the reactor vessel and support ledge into the containment space.

  18. Nuclear reactor overflow line

    DOEpatents

    Severson, Wayne J.

    1976-01-01

    The overflow line for the reactor vessel of a liquid-metal-cooled nuclear reactor includes means for establishing and maintaining a continuous bleed flow of coolant amounting to 5 to 10% of the total coolant flow through the overflow line to prevent thermal shock to the overflow line when the reactor is restarted following a trip. Preferably a tube is disposed concentrically just inside the overflow line extending from a point just inside the reactor vessel to an overflow tank and a suction line is provided opening into the body of liquid metal in the reactor vessel and into the annulus between the overflow line and the inner tube.

  19. LCEs for Naval Reactor Benchmark Calculations

    SciTech Connect

    W.J. Anderson

    1999-07-19

    The purpose of this engineering calculation is to document the MCNP4B2LV evaluations of Laboratory Critical Experiments (LCEs) performed as part of the Disposal Criticality Analysis Methodology program. LCE evaluations documented in this report were performed for 22 different cases with varied design parameters. Some of these LCEs (10) are documented in existing references (Ref. 7.1 and 7.2), but were re-run for this calculation file using more neutron histories. The objective of this analysis is to quantify the MCNP4B2LV code system's ability to accurately calculate the effective neutron multiplication factor (k{sub eff}) for various critical configurations. These LCE evaluations support the development and validation of the neutronics methodology used for criticality analyses involving Naval reactor spent nuclear fuel in a geologic repository.

  20. Spinning fluids reactor

    DOEpatents

    Miller, Jan D; Hupka, Jan; Aranowski, Robert

    2012-11-20

    A spinning fluids reactor, includes a reactor body (24) having a circular cross-section and a fluid contactor screen (26) within the reactor body (24). The fluid contactor screen (26) having a plurality of apertures and a circular cross-section concentric with the reactor body (24) for a length thus forming an inner volume (28) bound by the fluid contactor screen (26) and an outer volume (30) bound by the reactor body (24) and the fluid contactor screen (26). A primary inlet (20) can be operatively connected to the reactor body (24) and can be configured to produce flow-through first spinning flow of a first fluid within the inner volume (28). A secondary inlet (22) can similarly be operatively connected to the reactor body (24) and can be configured to produce a second flow of a second fluid within the outer volume (30) which is optionally spinning.

  1. High temperature reactors

    NASA Astrophysics Data System (ADS)

    Dulera, I. V.; Sinha, R. K.

    2008-12-01

    With the advent of high temperature reactors, nuclear energy, in addition to producing electricity, has shown enormous potential for the production of alternate transport energy carrier such as hydrogen. High efficiency hydrogen production processes need process heat at temperatures around 1173-1223 K. Bhabha Atomic Research Centre (BARC), is currently developing concepts of high temperature reactors capable of supplying process heat around 1273 K. These reactors would provide energy to facilitate combined production of hydrogen, electricity, and drinking water. Compact high temperature reactor is being developed as a technology demonstrator for associated technologies. Design has been also initiated for a 600 MWth innovative high temperature reactor. High temperature reactor development programme has opened new avenues for research in areas like advanced nuclear fuels, high temperature and corrosion resistant materials and protective coatings, heavy liquid metal coolant technologies, etc. The paper highlights design of these reactors and their material related requirements.

  2. Reactor water cleanup system

    DOEpatents

    Gluntz, Douglas M.; Taft, William E.

    1994-01-01

    A reactor water cleanup system includes a reactor pressure vessel containing a reactor core submerged in reactor water. First and second parallel cleanup trains are provided for extracting portions of the reactor water from the pressure vessel, cleaning the extracted water, and returning the cleaned water to the pressure vessel. Each of the cleanup trains includes a heat exchanger for cooling the reactor water, and a cleaner for cleaning the cooled reactor water. A return line is disposed between the cleaner and the pressure vessel for channeling the cleaned water thereto in a first mode of operation. A portion of the cooled water is bypassed around the cleaner during a second mode of operation and returned through the pressure vessel for shutdown cooling.

  3. Reactor water cleanup system

    DOEpatents

    Gluntz, D.M.; Taft, W.E.

    1994-12-20

    A reactor water cleanup system includes a reactor pressure vessel containing a reactor core submerged in reactor water. First and second parallel cleanup trains are provided for extracting portions of the reactor water from the pressure vessel, cleaning the extracted water, and returning the cleaned water to the pressure vessel. Each of the cleanup trains includes a heat exchanger for cooling the reactor water, and a cleaner for cleaning the cooled reactor water. A return line is disposed between the cleaner and the pressure vessel for channeling the cleaned water thereto in a first mode of operation. A portion of the cooled water is bypassed around the cleaner during a second mode of operation and returned through the pressure vessel for shutdown cooling. 1 figure.

  4. Variation of properties of glasses along the 3Bi2O3 X 5B2O3-4PbO X B2O3 and PbO X 2B2O3-2PbO X Bi2O3 sections of the PbO-Bi2O3-B2O3 ternary system

    SciTech Connect

    Zargarova, M.I.; Shuster, N.S.

    1985-07-01

    Already published data on the phase diagrams of Pb-B2O3, Bi2O3-B2O3, and PbO-Bi2O3 systems serve as the basis of this investigation, together with original experiments on the PbO-Bi2O3-B2O3 ternary system. The authors establish the quasi binary nature of the 3Bi2O3 X 5B2O3 - 4PbO X B2O3 section with the formation of the congruently melting ternary compound 3Bi2O3 X 8PbO X 7B2O3, and they demonstrate the role of the ternary compound 3Bi2O3 X 8PbO X 7B2O3 as a glass former in the PbO-Bi2O3 - B2O3 system.

  5. Hot corrosion of the B2 nickel aluminides

    NASA Technical Reports Server (NTRS)

    Ellis, David L.

    1993-01-01

    The hot corrosion behavior of the B2 nickel aluminides was studied to determine the inherent hot corrosion resistance of the beta nickel aluminides and to develop a mechanism for the hot corrosion of the beta nickel aluminides. The effects of the prior processing of the material, small additions of zirconium, stoichiometry of the materials, and preoxidation of the samples were also examined. Additions of 2, 5, and 15 w/o chromium were used to determine the effect of chromium on the hot corrosion of the beta nickel aluminides and the minimum amount of chromium necessary for good hot corrosion resistance. The results indicate that the beta nickel aluminides have inferior inherent hot corrosion resistance despite their excellent oxidation resistance. Prior processing and zirconium additions had no discernible effect on the hot corrosion resistance of the alloys. Preoxidation extended the incubation period of the alloys only a few hours and was not considered to be an effective means of stopping hot corrosion. Stoichiometry was a major factor in determining the hot corrosion resistance of the alloys with the higher aluminum alloys having a definitely superior hot corrosion resistance. The addition of chromium to the alloys stopped the hot corrosion attack in the alloys tested. From a variety of experimental results, a complex hot corrosion mechanism was proposed. During the early stages of the hot corrosion of these alloys the corrosion is dominated by a local sulphidation/oxidation form of attack. During the intermediate stages of the hot corrosion, the aluminum depletion at the surface leads to a change in the oxidation mechanism from a protective external alumina layer to a mixed nickel-aluminum spinel and nickel oxide that can occur both externally and internally. The material undergoes extensive cracking during the later portions of the hot corrosion.

  6. Thermal vacuum integrated system test at B-2

    NASA Astrophysics Data System (ADS)

    Kudlac, M. T.; Weaver, H. F.; Cmar, M. D.

    2012-04-01

    The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) Plum Brook Station (PBS) Space Propulsion Research Facility, commonly referred to as B-2, is NASA's third largest thermal vacuum facility. It is the largest designed to store and transfer large quantities of liquid hydrogen and liquid oxygen, and is perfectly suited to support developmental testing of chemical propulsion systems as well as fully integrated stages. The facility is also capable of providing thermal-vacuum simulation services to support testing of large lightweight structures, Cryogenic Fluid Management (CFM) systems, electric propulsion test programs, and other In-Space propulsion programs. A recently completed integrated system test demonstrated the refurbished thermal vacuum capabilities of the facility. The test used the modernized data acquisition and control system to monitor the facility during pump down of the vacuum chamber, operation of the liquid nitrogen heat sink (or cold wall) and the infrared lamp array. A vacuum level of 1.3 × 10-4 Pa (1 × 10-6 torr) was achieved. The heat sink provided a uniform temperature environment of approximately 77 K (139°R) along the entire inner surface of the vacuum chamber. The recently rebuilt and modernized infrared lamp array produced a nominal heat flux of 1.4 kW/m2 at a chamber diameter of 6.7 m (22 ft) and along 11 m (36 ft) of the chamber's cylindrical vertical interior. With the lamp array and heat sink operating simultaneously, the thermal systems produced a heat flux pattern simulating radiation to space on one surface and solar exposure on the other surface. The data acquired matched pretest predictions and demonstrated system functionality.

  7. TiB2 nanostructured coating for GFRP injection moulds.

    PubMed

    Martinho, R P; Silva, F J G; Alexandre, R J D; Baptista, A P M

    2011-06-01

    In the injection moulding of polypropylene reinforced with hard glass fibres, die materials are commonly subjected to severe abrasive wear. In order to improve its wear resistance, an unbalanced magnetron sputtering PVD compositional monolayered coating has been produced. The film was composed by a nanostructured TiB2 monolayer. Microstructure characterization and thickness evaluation were conducted by scanning electron microscopy (SEM). Film topography and roughness were accessed by SEM and Atomic Force Microscopy (AFM). The phase analyse was investigated by X-ray diffraction (XRD), using Cu Kalpha radiation. Scratch tests were conducted in order to study the film adhesion to the substrate. Load-Displacement curves (nanoindentation analysis) allowed measuring the film hardness and Young's modulus. A ball-cratering tribometer was used to determine the micro-abrasion laboratorial wear resistance, under different tests conditions, using SiC particles in distilled water slurry. At the end of these tests, the worn surfaces were analyzed by SEM and Energy Dispersive X-ray Spectroscopy (EDS) in order to compare these results with some other coatings already tested in the same conditions. To test the practical wear resistance, 135000 injection cycles were done in a plastic injection industrial mould. Coated samples were put on the plastic feed canal, after a turbulent zone. In these tests, a 30% (wt) glass fibres reinforced polypropylene was used. Worn sample surfaces were analyzed by SEM after 45.000 and 90.000 cycles. Image analyses were made in order to evaluate the damage increases and to observe the wear mechanisms involved.

  8. Thermal Vacuum Integrated System Test at B-2

    NASA Technical Reports Server (NTRS)

    Kudlac, Maureen T.; Weaver, Harold F.; Cmar, Mark D.

    2012-01-01

    The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) Plum Brook Station (PBS) Space Propulsion Research Facility, commonly referred to as B-2, is NASA s third largest thermal vacuum facility. It is the largest designed to store and transfer large quantities of liquid hydrogen and liquid oxygen, and is perfectly suited to support developmental testing of chemical propulsion systems as well as fully integrated stages. The facility is also capable of providing thermal-vacuum simulation services to support testing of large lightweight structures, Cryogenic Fluid Management (CFM) systems, electric propulsion test programs, and other In-Space propulsion programs. A recently completed integrated system test demonstrated the refurbished thermal vacuum capabilities of the facility. The test used the modernized data acquisition and control system to monitor the facility during pump down of the vacuum chamber, operation of the liquid nitrogen heat sink (or cold wall) and the infrared lamp array. A vacuum level of 1.3x10(exp -4)Pa (1x10(exp -6)torr) was achieved. The heat sink provided a uniform temperature environment of approximately 77 K (140deg R) along the entire inner surface of the vacuum chamber. The recently rebuilt and modernized infrared lamp array produced a nominal heat flux of 1.4 kW/sq m at a chamber diameter of 6.7 m (22 ft) and along 11 m (36 ft) of the chamber s cylindrical vertical interior. With the lamp array and heat sink operating simultaneously, the thermal systems produced a heat flux pattern simulating radiation to space on one surface and solar exposure on the other surface. The data acquired matched pretest predictions and demonstrated system functionality.

  9. Beyond the exchange--the future of B2B.

    PubMed

    Wise, R; Morrison, D

    2000-01-01

    Using the Internet to facilitate business-to-business commerce promises many benefits, such as dramatic cost reductions and greater access to buyers and sellers. Yet little is known about how B2B e-commerce will evolve. The authors argue that changes in the financial services industry over the past two decades provide important clues. Exchanges, they say, are not the primary source of value in information-intensive markets; value tends to accumulate among a diverse group of specialists that focus on such tasks as packaging, standard setting, arbitrage, and information management. Because scale and liquidity are vitally important to efficient trading, today's exchanges will consolidate into a relatively small set of mega-exchanges. Originators will handle the origination and aggregation of complex transactions before sending them on to mega-exchanges for execution. E-speculators, seeking to capitalize on an abundance of market information, will tend to concentrate where relatively standardized products can be transferred easily among a large group of buyers. In many markets, a handful of independent solution providers with well-known brand names and solid reputations will thrive alongside mega-exchanges. Sell-side asset exchanges will create the networks and provide the tools to allow suppliers to trade orders among themselves, sometimes after initial transactions with customers are made on the mega-exchanges. For many companies, traditional skills in such areas as product development, manufacturing, and marketing may become relatively less important, while the ability to understand and capitalize on market dynamics may become considerably more important.

  10. 26 CFR 1.668(b)-2 - Illustration of the provisions of subpart D.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 8 2012-04-01 2012-04-01 false Illustration of the provisions of subpart D. 1.668(b)-2 Section 1.668(b)-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Applicable to Taxable Years Beginning Before January 1, 1969 § 1.668(b)-2 Illustration of the provisions...

  11. 26 CFR 1.668(b)-2 - Illustration of the provisions of subpart D.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 8 2014-04-01 2014-04-01 false Illustration of the provisions of subpart D. 1.668(b)-2 Section 1.668(b)-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Applicable to Taxable Years Beginning Before January 1, 1969 § 1.668(b)-2 Illustration of the provisions...

  12. 26 CFR 1.668(b)-2 - Illustration of the provisions of subpart D.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Illustration of the provisions of subpart D. 1.668(b)-2 Section 1.668(b)-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Taxable Years Beginning Before January 1, 1969 § 1.668(b)-2 Illustration of the provisions of subpart...

  13. 26 CFR 1.668(b)-2 - Illustration of the provisions of subpart D.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 8 2013-04-01 2013-04-01 false Illustration of the provisions of subpart D. 1.668(b)-2 Section 1.668(b)-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Applicable to Taxable Years Beginning Before January 1, 1969 § 1.668(b)-2 Illustration of the provisions...

  14. 26 CFR 1.668(b)-2 - Illustration of the provisions of subpart D.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 8 2011-04-01 2011-04-01 false Illustration of the provisions of subpart D. 1.668(b)-2 Section 1.668(b)-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Applicable to Taxable Years Beginning Before January 1, 1969 § 1.668(b)-2 Illustration of the provisions...

  15. 17 CFR 240.13b2-1 - Falsification of accounting records.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 4 2014-04-01 2014-04-01 false Falsification of accounting records. 240.13b2-1 Section 240.13b2-1 Commodity and Securities Exchanges SECURITIES AND EXCHANGE... Required Reports § 240.13b2-1 Falsification of accounting records. No person shall directly or...

  16. 17 CFR 240.13b2-1 - Falsification of accounting records.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 17 Commodity and Securities Exchanges 3 2013-04-01 2013-04-01 false Falsification of accounting records. 240.13b2-1 Section 240.13b2-1 Commodity and Securities Exchanges SECURITIES AND EXCHANGE... Required Reports § 240.13b2-1 Falsification of accounting records. No person shall directly or...

  17. 26 CFR 1.367(b)-2 - Definitions and special rules.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (QBU) (B1) in France, whose functional currency is the euro. FC2, an unrelated foreign corporation... functional currency of the combined operations of B1 and B2 is the euro. (ii) Result. FC2's acquisition of... currency of the combined operations of B1 and B2 after the exchange is the euro, B2 is deemed to...

  18. 26 CFR 1.367(b)-2 - Definitions and special rules.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... (QBU) (B1) in France, whose functional currency is the euro. FC2, an unrelated foreign corporation... functional currency of the combined operations of B1 and B2 is the euro. (ii) Result. FC2's acquisition of... currency of the combined operations of B1 and B2 after the exchange is the euro, B2 is deemed to...

  19. 26 CFR 1.367(b)-2 - Definitions and special rules.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... (QBU) (B1) in France, whose functional currency is the euro. FC2, an unrelated foreign corporation... functional currency of the combined operations of B1 and B2 is the euro. (ii) Result. FC2's acquisition of... currency of the combined operations of B1 and B2 after the exchange is the euro, B2 is deemed to...

  20. 26 CFR 1.367(b)-2 - Definitions and special rules.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... (QBU) (B1) in France, whose functional currency is the euro. FC2, an unrelated foreign corporation... functional currency of the combined operations of B1 and B2 is the euro. (ii) Result. FC2's acquisition of... currency of the combined operations of B1 and B2 after the exchange is the euro, B2 is deemed to...

  1. 26 CFR 1.367(b)-2 - Definitions and special rules.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... (QBU) (B1) in France, whose functional currency is the euro. FC2, an unrelated foreign corporation... functional currency of the combined operations of B1 and B2 is the euro. (ii) Result. FC2's acquisition of... currency of the combined operations of B1 and B2 after the exchange is the euro, B2 is deemed to...

  2. 17 CFR 240.13b2-1 - Falsification of accounting records.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Falsification of accounting records. 240.13b2-1 Section 240.13b2-1 Commodity and Securities Exchanges SECURITIES AND EXCHANGE... Required Reports § 240.13b2-1 Falsification of accounting records. No person shall directly or...

  3. 26 CFR 1.652(b)-2 - Allocation of income items.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Allocation of income items. 1.652(b)-2 Section 1.652(b)-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Trusts Which Distribute Current Income Only § 1.652(b)-2 Allocation of income...

  4. 26 CFR 1.415(b)-2 - Multiple annuity starting dates. [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 5 2010-04-01 2010-04-01 false Multiple annuity starting dates. 1.415(b)-2 Section 1.415(b)-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Pension, Profit-Sharing, Stock Bonus Plans, Etc. § 1.415(b)-2 Multiple annuity starting...

  5. Expression of the ephrin receptor B2 in the embryonic chicken bursa of Fabricius

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chicken B-cells develop in a specific organ, the bursa of Fabricius. To understand the bursal microenvironment guiding B-cell development, previous studies identified ephrin (Eph) receptor B2 (EphB2) gene transcripts in the embryonic bursa. We hypothesize that the EphB2 receptors and their ligands r...

  6. Alloy Design Data Generated for B2-Ordered Compounds

    NASA Technical Reports Server (NTRS)

    Noebe, Ronald D.; Bozzolo, Guillermo; Abel, Phillip B.

    2003-01-01

    Developing alloys based on ordered compounds is significantly more complicated than developing designs based on disordered materials. In ordered compounds, the major constituent elements reside on particular sublattices. Therefore, the addition of a ternary element to a binary-ordered compound is complicated by the manner in which the ternary addition is made (at the expense of which binary component). When ternary additions are substituted for the wrong constituent, the physical and mechanical properties usually degrade. In some cases the resulting degradation in properties can be quite severe. For example, adding alloying additions to NiAl in the wrong combination (i.e., alloying additions that prefer the Al sublattice but are added at the expense of Ni) will severely embrittle the alloy to the point that it can literally fall apart during processing on cooling from the molten state. Consequently, alloying additions that strongly prefer one sublattice over another should always be added at the expense of that component during alloy development. Elements that have a very weak preference for a sublattice can usually be safely added at the expense of either element and will accommodate any deviation from stoichiometry by filling in for the deficient component. Unfortunately, this type of information is not known beforehand for most ordered systems. Therefore, a computational survey study, using a recently developed quantum approximate method, was undertaken at the NASA Glenn Research Center to determine the preferred site occupancy of ternary alloying additions to 12 different B2-ordered compounds including NiAl, FeAl, CoAl, CoFe, CoHf, CoTi, FeTi, RuAl, RuSi, RuHf, RuTi, and RuZr. Some of these compounds are potential high temperature structural alloys; others are used in thin-film magnetic and other electronic applications. The results are summarized. The italicized elements represent the previous sum total alloying information known and verify the computational

  7. HORIZONTAL BOILING REACTOR SYSTEM

    DOEpatents

    Treshow, M.

    1958-11-18

    Reactors of the boiling water type are described wherein water serves both as the moderator and coolant. The reactor system consists essentially of a horizontal pressure vessel divided into two compartments by a weir, a thermal neutronic reactor core having vertical coolant passages and designed to use water as a moderator-coolant posltioned in one compartment, means for removing live steam from the other compartment and means for conveying feed-water and water from the steam compartment to the reactor compartment. The system further includes auxiliary apparatus to utilize the steam for driving a turbine and returning the condensate to the feed-water inlet of the reactor. The entire system is designed so that the reactor is self-regulating and has self-limiting power and self-limiting pressure features.

  8. Hybrid reactors. [Fuel cycle

    SciTech Connect

    Moir, R.W.

    1980-09-09

    The rationale for hybrid fusion-fission reactors is the production of fissile fuel for fission reactors. A new class of reactor, the fission-suppressed hybrid promises unusually good safety features as well as the ability to support 25 light-water reactors of the same nuclear power rating, or even more high-conversion-ratio reactors such as the heavy-water type. One 4000-MW nuclear hybrid can produce 7200 kg of /sup 233/U per year. To obtain good economics, injector efficiency times plasma gain (eta/sub i/Q) should be greater than 2, the wall load should be greater than 1 MW.m/sup -2/, and the hybrid should cost less than 6 times the cost of a light-water reactor. Introduction rates for the fission-suppressed hybrid are usually rapid.

  9. Efficient generation of B2m-null pigs via injection of zygote with TALENs

    PubMed Central

    Wang, Yong; Du, Yinan; Zhou, Xiaoyang; Wang, Lulu; Li, Jian; Wang, Fengchao; Huang, Zhengen; Huang, Xingxu; Wei, Hong

    2016-01-01

    Donor major histocompatibility complex class I (MHC I) molecules are the main targets of the host immune response after organ allotransplantation. Whether and how MHC I-deficiency of pig donor tissues affects rejection after xenotransplantation has not been assessed. Beta2-microglobulin (B2M) is indispensable for the assembly of MHC I receptors and therefore provides an effective target to disrupt cell surface MHC I expression. Here, we report the one-step generation of mutant pigs with targeted disruptions in B2m by injection of porcine zygotes with B2m exon 2-specific TALENs. After germline transmission of mutant B2m alleles, we obtained F1 pigs with biallelic B2m frameshift mutations. F1 pigs lacked detectable B2M expression in tissues derived from the three germ layers, and their lymphocytes were devoid of MHC I surface receptors. Skin grafts from B2M deficient pigs exhibited remarkably prolonged survival on xenogeneic wounds compared to tissues of non-mutant littermates. Mutant founder pigs with bi-allelic disruption in B2m and B2M deficient F1 offspring did not display visible abnormalities, suggesting that pigs are tolerant to B2M deficiency. In summary, we show the efficient generation of pigs with germline mutations in B2m, and demonstrate a beneficial effect of donor MHC I-deficiency on xenotransplantation. PMID:27982048

  10. NEUTRONIC REACTOR SYSTEM

    DOEpatents

    Goett, J.J.

    1961-01-24

    A system is described which includes a neutronic reactor containing a dispersion of fissionable material in a liquid moderator as fuel and a conveyor to which a portion of the dispersion may be passed and wherein the self heat of the slurry evaporates the moderator. Means are provided for condensing the liquid moderator and returning it to the reactor and for conveying the dried fissionable material away from the reactor.

  11. NEUTRONIC REACTOR CONTROL

    DOEpatents

    Dreffin, R.S.

    1959-12-15

    A control means for a nuclear reactor is described. Particularly a device extending into the active portion of the reactor consisting of two hollow elements coaxially disposed and forming a channel therebetween, the cross sectional area of the channel increasing from each extremity of the device towards the center thereof. An element of neutron absorbing material is slidably positionable within the inner hollow element and a fluid reactor poison is introduced into the channel defined by the two hollow elements.

  12. The Integral Fast Reactor

    SciTech Connect

    Chang, Y.I.

    1988-01-01

    The Integral Fast Reactor (IFR) is an innovative liquid metal reactor concept being developed at Argonne National Laboratory. It seeks to specifically exploit the inherent properties of liquid metal cooling and metallic fuel in a way that leads to substantial improvements in the characteristics of the complete reactor system. This paper describes the key features and potential advantages of the IFR concept, with emphasis on its safety characteristics. 3 refs., 4 figs., 1 tab.

  13. Improved vortex reactor system

    DOEpatents

    Diebold, J.P.; Scahill, J.W.

    1995-05-09

    An improved vortex reactor system is described for affecting fast pyrolysis of biomass and Refuse Derived Fuel (RDF) feed materials comprising: a vortex reactor having its axis vertically disposed in relation to a jet of a horizontally disposed steam ejector that impels feed materials from a feeder and solids from a recycle loop along with a motive gas into a top part of said reactor. 12 figs.

  14. FLOW SYSTEM FOR REACTOR

    DOEpatents

    Zinn, W.H.

    1963-06-11

    A reactor is designed with means for terminating the reaction when returning coolant is below a predetermined temperature. Coolant flowing from the reactor passes through a heat exchanger to a lower reservoir, and then circulates between the lower reservoir and an upper reservoir before being returned to the reactor. Means responsive to the temperature of the coolant in the return conduit terminate the chain reaction when the temperature reaches a predetermined minimum value. (AEC)

  15. University Reactor Sharing Program

    SciTech Connect

    Dr. W.D. Reece

    1999-09-01

    The University Reactor Sharing Program provides funding for reactor experimentation to institutions that do not normally have access to a research reactor. Research projects supported by the program include items such as dating geological material to producing high current super conducting magnets. The funding also gives small colleges and universities the opportunity to use the facility for teaching courses in nuclear processes; specifically neutron activation analysis and gamma spectroscopy.

  16. Microstructure and mechanical properties investigation of in situ TiB2 and ZrB2 reinforced Al-4Cu composites

    NASA Astrophysics Data System (ADS)

    Lutfi Anis, Ahmad; Ramli, Rosmamuhammadani; Darham, Widyani; Zakaria, Azlan; Talari, Mahesh Kumar

    2016-02-01

    Conventional Al-Cu alloys exhibit coarse grain structure leading to inferior mechanical properties in as-cast condition. Expensive thermo-mechanical treatments are needed to improve microstructure and corresponding mechanical properties. In situ Al-based composites were developed to improve mechanical properties by dispersion strengthening and grain refinement obtained by the presence of particulates in the melt during solidification. In this work Al-4Cu - 3TiB2 and Al-4Cu-3ZrB2 in situ composites were prepared by liquid casting method. XRD, electron microscopy and mechanical tests were performed on suitably sectioned and metallographically prepared surfaces to investigate the phase distribution, hardness and tensile properties. It was found that the reinforcement particles were segregated along the grain boundaries of Al dendrites. Tensile fracture morphology for both Al-4Cu - 3TiB2 and Al-4Cu-3ZrB2 were analyzed and compared to determine the fracture propagation mechanism in the composites. Al-4Cu-3ZrB2 in situ composites displayed higher strength and hardness compared to Al-4Cu-3TiB2 which could be ascribed to the stronger interfacial bonding between the Al dendrites and ZrB2 particulates as evidenced from fractographs.

  17. BPO4@B2O3 and (BPO4@B2O3):Eu3+: The novel single-emitting-component phosphors for near UV-white LEDs

    NASA Astrophysics Data System (ADS)

    Cao, Xiyu; Liu, Wei; Jiang, Yu; Cao, Lixin; Su, Ge; Gao, Rongjie

    2016-08-01

    Nowadays much effort has been devoted to exploring novel luminescent materials with low-cost, high stability and excellent luminescent properties. In this paper, a new kind of luminescent material BPO4@B2O3 was prepared by using a facile method. The as-obtained samples contain numerous BPO4 nanoparticles enclosed by amorphous and crystalline B2O3 homogeneously, which exhibits a broad emission band ranging from 380 to 700 nm under near-UV irradiation. More importantly, it is worth noting that the BPO4@B2O3 phosphor exhibits the excellent thermal quenching property, which endows it with a promising prospect as phosphors for high power white LEDs. To further promote its application as white light phosphors, Eu3+ ions were doped into the BPO4@B2O3 samples and prepared the (BPO4@B2O3):Eu3+ phosphors with chromaticity coordinates (0.3022, 0.3122). The corresponding packaging of LEDs indicates that both BPO4@B2O3 and (BPO4@B2O3):Eu3+ can be considered as the promising phosphors for WLEDs.

  18. capB2 Expression Is Associated with Staphylococcus aureus Pathogenicity

    PubMed Central

    Li, Dan; Guo, Yinjuan; Wang, Shanshan; Lv, Jingnan; Qi, Xiuqin; Chen, Zengqiang; Han, Lizhong; Zhang, Xueqing; Wang, Liangxing; Yu, Fangyou

    2017-01-01

    CapB2 is recognized as a tyrosine kinase and is likely a vital factor in extracellular polysaccharide synthesis in Staphylococcus aureus, but its pathogenicity function and regulatory mechanism remain obscure. Here, we demonstrate that CapB2 enhances bacterial virulence in a murine model. Mice infected with the wild type SA75 strain exhibited significantly larger (P < 0.05) skin lesions from days 4 to 7 of infection than those challenged with the capB2 mutant strain. The effect on virulence was reverted by restoring the capB2 mutation to the wild type. The related components of the wild type SA75 cell wall in the capB2 mutant strain (SA75ΔcapB2) were thinner than wild type SA75 strain and the capB2 mutant complemented strain (SA75ΔcapB2-C), which was determined by the transmission electron microscopy. The survival percentages of the wild type strain SA75 and SA75ΔcapB2-C were significantly higher relative to SA75ΔcapB2. The results of qRT-PCR studies also indicated that mutations in regulatory gene sarA led to a drastic increase in capB2 gene transcription, with a 326-fold increase of growth at 6 h compared with the wild type strain, suggesting that sarA is a major negative regulator of capB2 expression. Taken together, these results demonstrate that the expression of CapB2 promotes S. aureus virulence in a mouse model of skin infection, and that capB2 gene transcription is regulated negatively by SarA. PMID:28239370

  19. Secretion of SerpinB2 from endothelial cells activated with inflammatory stimuli

    SciTech Connect

    Boncela, Joanna; Przygodzka, Patrycja; Wyroba, Elzbieta; Papiewska-Pajak, Izabela; Cierniewski, Czeslaw S.

    2013-05-01

    Due to the lack of an N-terminal signal peptide, SerpinB2 (plasminogen activator inhibitor type 2) accumulates in cells and only a small percentage of it is secreted. The extracellular concentration of SerpinB2 significantly increases during inflammation. In the present study we investigated the mechanism with which SerpinB2 can be secreted from endothelial cells activated with LPS. We evaluated the intracellular distribution of SerpinB2 by double immunogold labeling followed by a high resolution electron microscopy analysis. We found that SerpinB2 gathers in the vesicular structures and in the endothelial cell periphery. These vesicles stained positive for the trans-Golgi network marker TGN46, which is consistent with their formation by the endoplasmatic reticulum (ER) and Golgi-dependent pathways. SerpinB2 was delivered to the plasma membrane, apparently together with TGN46 in the same vesicles, which after fusion with the membranes released cargo. Secretion of SerpinB2 was partially inhibited by brefeldin A. The secreted SerpinB2 was predominantly in its nonglycosylated 43 kDa form as evaluated by Western immunoblotting. Our data suggest that increased expression of SerpinB2 by an inflammatory stimulus is sufficient to generate structures that resemble secretory vesicles. These vesicles may represent the mechanism by which high local concentrations of SerpinB2 are released at inflammation sites from endothelial cells. - Highlights: ► LPS stimulates generation of secretory vesicles containing SerpinB2. ► SerpinB2 concentrates in TGN46 positive vesicles close to the plasma membrane. ► Brefeldin A inhibits secretion of SerpinB2. ► The secreted SerpinB2 was predominantly in its nonglycosylated 43 kDa.

  20. c-erbB-2 in serum of patients receiving fractionated paclitaxel chemotherapy.

    PubMed

    Lüftner, D; Schnabel, S; Possinger, K

    1999-01-01

    Humanized anti-c-erbB-2 antibodies (Herceptin) in a weekly schedule are a new therapeutic option for the treatment of c-erbB-2-positive, advanced breast cancer (ABC). Addition of Herceptin to first-line chemotherapy for c-erbB-2 overexpressing ABC increased anticancer activity in a randomized phase III trial. However, except from standard UICC response criteria, there are hitherto no recommendations as to how to monitor Herceptin therapy. In a therapy optimizing study with weekly dose-intensified paclitaxel monotherapy (schedule: 90 mg/m2 weekly x 6, q9w), we correlated the clinical course of stage IV breast cancer in UICC criteria with the course of the shed c-erbB-2 protein fragment and the CA 27.29 serum level. Serum samples were taken weekly from 35 patients to measure the serum c-erbB-2 and CA 27.29 protein levels over time. Up to now, 10 patients (28.5%) are c-erbB-2 positive (> 15 U/mL), with a median baseline protein expression of 65 U/mL. While the overall response rate in the study is 36%, the response rate among c-erbB-2-positive patients is 62%, indicating a high sensitivity of c-erbB-2 positive patients to dose-intense paclitaxel treatment. In all responders the c-erbB-2 serum level decreased below the detection limit either before the clinical diagnosis of response or by the end of the next cycle. However, the normalization of the c-erbB-2 serum level was not specific for responders as patients with stable or progressive disease presented normalized levels or a > 50% decrease of the baseline level, too. The courses of the c-erbB-2 protein levels correlated closely with the courses of CA 27.29. The decrease in the serum c-erbB-2 oncoprotein level might indicate a regression of c-erbB-2 positive tumor load. This may even happen in progressive disease according to UICC criteria when the c-erbB-2-negative tumor fraction progresses while the c-erbB-2-positive fraction is controlled. Another explanation would be that the mechanisms of c-erbB-2 shedding

  1. Gemini vitamin D analog suppresses ErbB2-positive mammary tumor growth via inhibition of ErbB2/AKT/ERK signaling.

    PubMed

    Lee, Hong Jin; So, Jae-Young; DeCastro, Andrew; Smolarek, Amanda; Paul, Shiby; Maehr, Hubert; Uskokovic, Milan; Suh, Nanjoo

    2010-07-01

    Numerous synthetic vitamin D analogs have been studied for their effects on the prevention and treatment of breast cancer. However, the inhibitory effects of naturally occurring 1alpha,25-dihydroxyvitamin D3 or its synthetic analogs on ErbB2 overexpressing mammary tumorigenesis have not been reported. Gemini vitamin D analogs are novel synthetic vitamin D derivatives with a unique structure of two six-carbon chains at C-20. We have previously shown that Gemini vitamin D analogs significantly inhibited carcinogen-induced estrogen receptor (ER)-positive mammary tumorigenesis and reduced ER-negative MCF10DCIS.com xenograft tumor growth without hypercalcemic toxicity. In the present study, we have determined the inhibitory effect of a potent Gemini vitamin D analog BXL0124 (1alpha,25-dihydroxy-20R-21(3-hydroxy-3-deuteromethyl-4,4,4-trideuterobutyl)-23-yne-26,27-hexafluoro-cholecalciferol) on the ErbB2/Her-2/neu overexpressing mammary tumorigenesis. The Gemini BXL0124 inhibits ErbB2-positive mammary tumor growth and down-regulates the phosphorylation of ErbB2, ERK and AKT in tumors of MMTV-ErbB2/neu transgenic mice. These effects of Gemini BXL0124 in vivo were confirmed by using the ErbB2 overexpressing tumor cells derived from the mammary tumors of MMTV-ErbB2/neu mice. In conclusion, the Gemini vitamin D analog BXL0124 inhibits the growth of ErbB2 overexpressing mammary tumors through regulating the ErbB2/AKT/ERK signaling pathways, suggesting that Gemini vitamin D analog may be considered for translational studies.

  2. HOMOGENEOUS NUCLEAR POWER REACTOR

    DOEpatents

    King, L.D.P.

    1959-09-01

    A homogeneous nuclear power reactor utilizing forced circulation of the liquid fuel is described. The reactor does not require fuel handling outside of the reactor vessel during any normal operation including complete shutdown to room temperature, the reactor being selfregulating under extreme operating conditions and controlled by the thermal expansion of the liquid fuel. The liquid fuel utilized is a uranium, phosphoric acid, and water solution which requires no gus exhaust system or independent gas recombining system, thereby eliminating the handling of radioiytic gas.

  3. Membrane reactors at Degussa.

    PubMed

    Wöltinger, Jens; Karau, Andreas; Leuchtenberger, Wolfgang; Drauz, Karlheinz

    2005-01-01

    The review covers the development of membrane reactor technologies at Degussa for the synthesis of fine chemicals. The operation of fed-batch or continuous biocatalytic processes in the enzyme membrane reactor (EMR) is well established at Degussa. Degussa has experience of running EMRs from laboratory gram scale up to a production scale of several hundreds of tons per year. The transfer of the enzyme membrane reactor from biocatalysis to chemical catalysis in the chemzyme membrane reactor (CMR) is discussed. Various homogeneous catalysts have been investigated in the CMR, and the scope and limitation of this new technique is discussed.

  4. Pressurized fluidized bed reactor

    DOEpatents

    Isaksson, J.

    1996-03-19

    A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine. 1 fig.

  5. Pressurized fluidized bed reactor

    DOEpatents

    Isaksson, Juhani

    1996-01-01

    A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine.

  6. Remote Reactor Monitoring

    SciTech Connect

    Bernstein, Adam; Dazeley, Steve; Dobie, Doug; Marleau, Peter; Brennan, Jim; Gerling, Mark; Sumner, Matthew; Sweany, Melinda

    2014-10-21

    The overall goal of the WATCHMAN project is to experimentally demonstrate the potential of water Cerenkov antineutrino detectors as a tool for remote monitoring of nuclear reactors. In particular, the project seeks to field a large prototype gadolinium-doped, water-based antineutrino detector to demonstrate sensitivity to a power reactor at ~10 kilometer standoff using a kiloton scale detector. The technology under development, when fully realized at large scale, could provide remote near-real-time information about reactor existence and operational status for small operating nuclear reactors out to distances of many hundreds of kilometers.

  7. Dual-Layer Oxidation-Protective Plasma-Sprayed SiC-ZrB2/Al2O3-Carbon Nanotube Coating on Graphite

    NASA Astrophysics Data System (ADS)

    Ariharan, S.; Sengupta, Pradyut; Nisar, Ambreen; Agnihotri, Ankur; Balaji, N.; Aruna, S. T.; Balani, Kantesh

    2016-12-01

    Graphite is used in high-temperature gas-cooled reactors because of its outstanding irradiation performance and corrosion resistance. To restrict its high-temperature (>873 K) oxidation, atmospheric-plasma-sprayed SiC-ZrB2-Al2O3-carbon nanotube (CNT) dual-layer coating was deposited on graphite substrate in this work. The effect of each layer was isolated by processing each component of the coating via spark plasma sintering followed by isothermal kinetic studies. Based on isothermal analysis and the presence of high residual thermal stress in the oxide scale, degradation appeared to be more severe in composites reinforced with CNTs. To avoid the complexity of analysis of composites, the high-temperature activation energy for oxidation was calculated for the single-phase materials only, yielding values of 11.8, 20.5, 43.5, and 4.5 kJ/mol for graphite, SiC, ZrB2, and CNT, respectively, with increased thermal stability for ZrB2 and SiC. These results were then used to evaluate the oxidation rate for the composites analytically. This study has broad implications for wider use of dual-layer (SiC-ZrB2/Al2O3) coatings for protecting graphite crucibles even at temperatures above 1073 K.

  8. Dual-Layer Oxidation-Protective Plasma-Sprayed SiC-ZrB2/Al2O3-Carbon Nanotube Coating on Graphite

    NASA Astrophysics Data System (ADS)

    Ariharan, S.; Sengupta, Pradyut; Nisar, Ambreen; Agnihotri, Ankur; Balaji, N.; Aruna, S. T.; Balani, Kantesh

    2017-02-01

    Graphite is used in high-temperature gas-cooled reactors because of its outstanding irradiation performance and corrosion resistance. To restrict its high-temperature (>873 K) oxidation, atmospheric-plasma-sprayed SiC-ZrB2-Al2O3-carbon nanotube (CNT) dual-layer coating was deposited on graphite substrate in this work. The effect of each layer was isolated by processing each component of the coating via spark plasma sintering followed by isothermal kinetic studies. Based on isothermal analysis and the presence of high residual thermal stress in the oxide scale, degradation appeared to be more severe in composites reinforced with CNTs. To avoid the complexity of analysis of composites, the high-temperature activation energy for oxidation was calculated for the single-phase materials only, yielding values of 11.8, 20.5, 43.5, and 4.5 kJ/mol for graphite, SiC, ZrB2, and CNT, respectively, with increased thermal stability for ZrB2 and SiC. These results were then used to evaluate the oxidation rate for the composites analytically. This study has broad implications for wider use of dual-layer (SiC-ZrB2/Al2O3) coatings for protecting graphite crucibles even at temperatures above 1073 K.

  9. Spectroscopic and modeling investigations of the gas-phase chemistry and composition in microwave plasma activated B2H6/Ar/H2 mixtures.

    PubMed

    Ma, Jie; Richley, James C; Davies, David R W; Cheesman, Andrew; Ashfold, Michael N R; Mankelevich, Yuri A

    2010-02-25

    This paper describes a three-pronged study of microwave (MW) activated B(2)H(6)/Ar/H(2) plasmas as a precursor to diagnosis of the B(2)H(6)/CH(4)/Ar/H(2) plasmas used for the chemical vapor deposition of B-doped diamond. Absolute column densities of B atoms and BH radicals have been determined by cavity ring-down spectroscopy as a function of height (z) above a molybdenum substrate and of the plasma process conditions (B(2)H(6) and Ar partial pressures, total pressure, and supplied MW power). Optical emission spectroscopy has been used to explore variations in the relative densities of electronically excited BH, H, and H(2) species as a function of the same process conditions and of time after introducing B(2)H(6) into a pre-existing Ar/H(2) plasma. The experimental measurements are complemented by extensive 2-D(r, z) modeling of the plasma chemistry, which results in refinements to the existing B/H chemistry and thermochemistry and demonstrates the potentially substantial loss of gas-phase BH(x) species through reaction with trace quantities of air/O(2) in the process gas mixture and heterogeneous processes occurring at the reactor wall.

  10. Properties of ZrB2 Thin Films Grown by E-Beam Evaporation

    NASA Astrophysics Data System (ADS)

    Lad, Robert; Stewart, David; Sell, Julia; Bernhardt, George; Frankel, David; University of Maine Team

    2014-03-01

    Zirconium diboride (ZrB2) is a candidate material for many high temperature applications because it has a high melting point, high hardness, thermal shock resistance, and metallic conductivity. However, very little work has been reported concerning growth of ZrB2 thin films and high temperature oxidation behavior. In this study, ZrB2 films with nominal thickness of 200 nm have been deposited using electron-beam evaporation of either ZrB2 pellets or elemental B and Zr sources. The ZrB2 source yields a film that has a 1:1 Zr:B average composition as measured by X-ray photoelectron spectroscopy, consisting of ZrB2 precipitates within an amorphous Zr matrix as determined by X-ray diffraction. Use of elemental B and Zr sources allows precise control of film growth over a range of stoichiometries and yields ZrB2 films with much lower oxygen contamination. After annealing ZrB2 films to 1200°C in air, oxidation leads to a loss of B and formation of a textured monoclinic ZrO2 phase. Several strategies, including deposition of a thin Al2O3 capping layer over the ZrB2 film are being pursued in an attempt to stabilize the electrically conductive ZrB2 phase at high temperature, where it can be used for high temperature electronic devices in harsh environments. Supported by NSF grant # 1309983.

  11. Role of Erbin in ErbB2-dependent breast tumor growth

    PubMed Central

    Tao, Yanmei; Shen, Chengyong; Luo, Shiwen; Traoré, Wilfried; Marchetto, Sylvie; Santoni, Marie-Josée; Xu, Linlin; Wu, Biao; Shi, Chao; Mei, Jinghong; Bates, Ryan; Liu, Xihui; Zhao, Kai; Xiong, Wen-Cheng; Borg, Jean-Paul; Mei, Lin

    2014-01-01

    ErbB2 (v-erb-b2 avian erythroblastic leukemia viral oncogene homolog 2), a receptor tyrosine kinase of the ErbB family, is overexpressed in around 25% of breast cancers. In addition to forming a heterodimer with other ErbB receptors in response to ligand stimulation, ErbB2 can be activated in a ligand-independent manner. We report here that Erbin, an ErbB2-interacting protein that was thought to act as an antitumor factor, is specifically expressed in mammary luminal epithelial cells and facilitates ErbB2-dependent proliferation of breast cancer cells and tumorigenesis in MMTV-neu transgenic mice. Disruption of their interaction decreases ErbB2-dependent proliferation, and deletion of the PDZ domain in Erbin hinders ErbB2-dependent tumor development in MMTV-neu mice. Mechanistically, Erbin forms a complex with ErbB2, promotes its interaction with the chaperon protein HSP90, and thus prevents its degradation. Finally, ErbB2 and Erbin expression correlates in human breast tumor tissues. Together, these observations establish Erbin as an ErbB2 regulator for breast tumor formation and progression. PMID:25288731

  12. Role of Erbin in ErbB2-dependent breast tumor growth.

    PubMed

    Tao, Yanmei; Shen, Chengyong; Luo, Shiwen; Traoré, Wilfried; Marchetto, Sylvie; Santoni, Marie-Josée; Xu, Linlin; Wu, Biao; Shi, Chao; Mei, Jinghong; Bates, Ryan; Liu, Xihui; Zhao, Kai; Xiong, Wen-Cheng; Borg, Jean-Paul; Mei, Lin

    2014-10-21

    ErbB2 (v-erb-b2 avian erythroblastic leukemia viral oncogene homolog 2), a receptor tyrosine kinase of the ErbB family, is overexpressed in around 25% of breast cancers. In addition to forming a heterodimer with other ErbB receptors in response to ligand stimulation, ErbB2 can be activated in a ligand-independent manner. We report here that Erbin, an ErbB2-interacting protein that was thought to act as an antitumor factor, is specifically expressed in mammary luminal epithelial cells and facilitates ErbB2-dependent proliferation of breast cancer cells and tumorigenesis in MMTV-neu transgenic mice. Disruption of their interaction decreases ErbB2-dependent proliferation, and deletion of the PDZ domain in Erbin hinders ErbB2-dependent tumor development in MMTV-neu mice. Mechanistically, Erbin forms a complex with ErbB2, promotes its interaction with the chaperon protein HSP90, and thus prevents its degradation. Finally, ErbB2 and Erbin expression correlates in human breast tumor tissues. Together, these observations establish Erbin as an ErbB2 regulator for breast tumor formation and progression.

  13. Bioassay methods for detection of N-palmitoylbrevetoxin-B2 (BTX-B4).

    PubMed

    Bottein, Marie-Yasmine Dechraoui; Fuquay, Jennifer Maucher; Munday, Rex; Selwood, Andrew I; van Ginkel, Roel; Miles, Christopher O; Loader, Jared I; Wilkins, Alistair L; Ramsdell, John S

    2010-01-01

    Brevetoxins (BTXs) are a class of cyclic polyether toxins produced by the dinoflagellate Karenia brevis. These substances are subject to extensive conjugative metabolism in shellfish. BTX-B forms a conjugate with cysteine and is oxidized and reduced to yield BTX-B2, which is further modified by fatty acid addition via cysteine amide linkage to give biologically active brevetoxin metabolites. In this study, we evaluated the commonly used in vitro (ELISA, radioimmunoassay, receptor binding assay and N2A cytotoxicity assay) and in vivo mouse brevetoxin bioassays for the detection of the brevetoxin fatty acid conjugate N-palmitoylBTX-B2, and compared the results to those for dihydroBTX-B and BTX-B2. The receptor binding assay for N-palmitoylBTX-B2 showed comparable sensitivity to that for dihydroBTX-B, and an 11-fold higher sensitivity than for BTX-B2. Although the ELISA showed similarly high sensitivity to dihydroBTX-B and BTX-B2, with EC(50) values of ca. 0.26 ng/ml, it was 23 times less sensitive to N-palmitoylBTX-B2. On the other hand, the N2A cytotoxicity assay was highly sensitive to N-palmitoylBTX-B2, with an EC(50) of 0.15 ng/ml, but was 12- and 40-fold less sensitive to dihydroBTX-B and BTX-B2, respectively. The relative sensitivity of the N2A cytotoxicity assay for each of these metabolites paralleled that of the mouse bioassay (relative LD(50) values 1:20:30 for N-palmitoylBTX-B2:dihydroBTX-B:BTX-B2). We conclude that the most sensitive bioassay for dihydroBTX-B and BTX-B2 is the ELISA, whereas the N2A cytotoxicity assay is most sensitive for N-palmitoylBTX-B2.

  14. First Observation of the nu(17)-nu(4) Difference Bands of Diborane (10)B(2)H(6) and (11)B(2)H(6).

    PubMed

    Flaud; Lafferty; Bürger; Pawelke; Domenech; Bermejo

    2000-10-01

    An analysis of the nu(17)-nu(4) difference bands near 800 cm(-1) of two isotopic species, (10)B(2)H(6) and (11)B(2)H(6), of diborane has been carried out using infrared spectra recorded with a resolution of ca. 0.003 cm(-1). In addition, the nu(17) band of (10)B(2)H(6) has been recorded and assigned. Since this band in (11)B(2)H(6) had already been studied (R. L. Sams, T. A. Blake, S. W. Sharpe, J.-M. Flaud, and W. J. Lafferty, J. Mol. Spectrosc. 191, 331-342 (1998)), it was possible to derive precise energy levels and Hamiltonian constants for the 4(1) vibrational states of both isotopic species. Copyright 2000 Academic Press.

  15. Observation of b2 symmetry vibrational levels of the SO2C 1B2 state: Vibrational level staggering, Coriolis interactions, and rotation-vibration constants

    DOE PAGES

    Park, G. Barratt; Jiang, Jun; Saladrigas, Catherine A.; ...

    2016-04-14

    Here, the C 1B2 state of SO2 has a double-minimum potential in the antisymmetric stretch coordinate, such that the minimum energy geometry has nonequivalent SO bond lengths. However, low-lying levels with odd quanta of antisymmetric stretch (b2 vibrational symmetry) have not previously been observed because transitions into these levels from the zero-point level of the X~ state are vibronically forbidden. We use IR-UV double resonance to observe the b2 vibrational levels of the C state below 1600 cm–1 of vibrational excitation. This enables a direct characterization of the vibrational level staggering that results from the double-minimum potential. In addition, itmore » allows us to deperturb the strong c-axis Coriolis interactions between levels of a1 and b2 vibrational symmetry, and to determine accurately the vibrational dependence of the rotational constants in the distorted C electronic state.« less

  16. Observation of b2 symmetry vibrational levels of the SO2 C̃ (1)B2 state: Vibrational level staggering, Coriolis interactions, and rotation-vibration constants.

    PubMed

    Park, G Barratt; Jiang, Jun; Saladrigas, Catherine A; Field, Robert W

    2016-04-14

    The C̃ (1)B2 state of SO2 has a double-minimum potential in the antisymmetric stretch coordinate, such that the minimum energy geometry has nonequivalent SO bond lengths. However, low-lying levels with odd quanta of antisymmetric stretch (b2 vibrational symmetry) have not previously been observed because transitions into these levels from the zero-point level of the X̃ state are vibronically forbidden. We use IR-UV double resonance to observe the b2 vibrational levels of the C̃ state below 1600 cm(-1) of vibrational excitation. This enables a direct characterization of the vibrational level staggering that results from the double-minimum potential. In addition, it allows us to deperturb the strong c-axis Coriolis interactions between levels of a1 and b2 vibrational symmetry and to determine accurately the vibrational dependence of the rotational constants in the distorted C̃ electronic state.

  17. CaMsrB2, Pepper Methionine Sulfoxide Reductase B2, Is a Novel Defense Regulator against Oxidative Stress and Pathogen Attack1[C][W

    PubMed Central

    Oh, Sang-Keun; Baek, Kwang-Hyun; Seong, Eun Soo; Joung, Young Hee; Choi, Gyung-Ja; Park, Jeong Mee; Cho, Hye Sun; Kim, Eun Ah; Lee, Sangku; Choi, Doil

    2010-01-01

    Reactive oxygen species (ROS) are inevitably generated in aerobic organisms as by-products of normal metabolism or as the result of defense and development. ROS readily oxidize methionine (Met) residues in proteins/peptides to form Met-R-sulfoxide or Met-S-sulfoxide, causing inactivation or malfunction of the proteins. A pepper (Capsicum annuum) methionine sulfoxide reductase B2 gene (CaMsrB2) was isolated, and its roles in plant defense were studied. CaMsrB2 was down-regulated upon inoculation with either incompatible or compatible pathogens. The down-regulation, however, was restored to the original expression levels only in a compatible interaction. Gain-of-function studies using tomato (Solanum lycopersicum) plants transformed with CaMsrB2 resulted in enhanced resistance to Phytophthora capsici and Phytophthora infestans. Inversely, loss-of-function studies of CaMsrB2 using virus-induced gene silencing in pepper plants (cv Early Calwonder-30R) resulted in accelerated cell death from an incompatible bacterial pathogen, Xanthomonas axonopodis pv vesicatoria (Xav) race 1, and enhanced susceptibility to a compatible bacterial pathogen, virulent X. axonopodis pv vesicatoria race 3. Measurement of ROS levels in CaMsrB2-silenced pepper plants revealed that suppression of CaMsrB2 increased the production of ROS, which in turn resulted in the acceleration of cell death via accumulation of ROS. In contrast, the CaMsrB2-transgenic tomato plants showed reduced production of hydrogen peroxide. Taken together, our results suggest that the plant MsrBs have novel functions in active defense against pathogens via the regulation of cell redox status. PMID:20643759

  18. Polymerization Reactor Engineering.

    ERIC Educational Resources Information Center

    Skaates, J. Michael

    1987-01-01

    Describes a polymerization reactor engineering course offered at Michigan Technological University which focuses on the design and operation of industrial polymerization reactors to achieve a desired degree of polymerization and molecular weight distribution. Provides a list of the course topics and assigned readings. (TW)

  19. N Reactor hydrogen control

    SciTech Connect

    Shuford, D.H.; Kripps, L.J.

    1988-08-01

    Following the accident at the Chernobyl nuclear power reactor in the Soviet Union, a number of reviews were conducted of the N Reactor. Hydrogen generation during postulates severe accidents and the possibility of resulting hydrogen deflagrations/detonations that could affect confinement integrity were issues raised in several reviews, along with recommendations for adding hydrogen mitigation features. To respond to these reviews, an N Reactor Safety Enhancement Program and a subsequent Accelerated Safety Enhancement Program were initiated to address all post-Chernobyl N Reactor review findings. The Safety Enhancement Program and Accelerated Safety Enhancement Program efforts involving hydrogen control included the following: Calculate the potential hydrogen source for a range of severe accidents at the N Reactor to establish an acceptable design basis for the hydrogen mitigation system; Analyze the N Reactor confinement hydrogen mixing capability to identify areas of concern and to the verify effectiveness of the hydrogen mitigation system; Select, design, and construct a hydrogen mitigation system to enhance the N Reactor capability to accommodate possible hydrogen generation from postulated severe accidents; Provide post-accident hydrogen monitoring as an operator aid in assessing confinement conditions. In additions, it was necessary to verify that incorporation of the hydrogen mitigation system had no adverse impact N Reactor safety (e.g., radiological consequence analyses). 77 refs., 25 figs., 10 tabs.

  20. NEUTRONIC REACTOR SYSTEM

    DOEpatents

    Treshow, M.

    1959-02-10

    A reactor system incorporating a reactor of the heterogeneous boiling water type is described. The reactor is comprised essentially of a core submerged adwater in the lower half of a pressure vessel and two distribution rings connected to a source of water are disposed within the pressure vessel above the reactor core, the lower distribution ring being submerged adjacent to the uppcr end of the reactor core and the other distribution ring being located adjacent to the top of the pressure vessel. A feed-water control valve, responsive to the steam demand of the load, is provided in the feedwater line to the distribution rings and regulates the amount of feed water flowing to each distribution ring, the proportion of water flowing to the submerged distribution ring being proportional to the steam demand of the load. This invention provides an automatic means exterior to the reactor to control the reactivity of the reactor over relatively long periods of time without relying upon movement of control rods or of other moving parts within the reactor structure.

  1. NEUTRONIC REACTOR BURIAL ASSEMBLY

    DOEpatents

    Treshow, M.

    1961-05-01

    A burial assembly is shown whereby an entire reactor core may be encased with lead shielding, withdrawn from the reactor site and buried. This is made possible by a five-piece interlocking arrangement that may be easily put together by remote control with no aligning of bolt holes or other such close adjustments being necessary.

  2. REFLECTOR FOR NEUTRONIC REACTORS

    DOEpatents

    Fraas, A.P.

    1963-08-01

    A reflector for nuclear reactors that comprises an assembly of closely packed graphite rods disposed with their major axes substantially perpendicular to the interface between the reactor core and the reflector is described. Each graphite rod is round in transverse cross section at (at least) its interface end and is provided, at that end, with a coaxial, inwardly tapering hole. (AEC)

  3. The Integral Fast Reactor

    SciTech Connect

    Till, C.E.; Chang, Y.I. ); Lineberry, M.J. )

    1990-01-01

    Argonne National Laboratory, since 1984, has been developing the Integral Fast Reactor (IFR). This paper will describe the way in which this new reactor concept came about; the technical, public acceptance, and environmental issues that are addressed by the IFR; the technical progress that has been made; and our expectations for this program in the near term. 5 refs., 3 figs.

  4. Light water reactor program

    SciTech Connect

    Franks, S.M.

    1994-12-31

    The US Department of Energy`s Light Water Reactor Program is outlined. The scope of the program consists of: design certification of evolutionary plants; design, development, and design certification of simplified passive plants; first-of-a-kind engineering to achieve commercial standardization; plant lifetime improvement; and advanced reactor severe accident program. These program activities of the Office of Nuclear Energy are discussed.

  5. Microhardness and microstructure evolution of TiB2 reinforced Inconel 625/TiB2 composite produced by selective laser melting

    NASA Astrophysics Data System (ADS)

    Zhang, Baicheng; Bi, Guijun; Nai, Sharon; Sun, Chen-nan; Wei, Jun

    2016-06-01

    In this study, micron-size TiB2 particles were utilized to reinforce Inconel 625 produced by selective laser melting. Exceptional microhardness 600-700 HV0.3 of the composite was obtained. In further investigation, the microstructure and mechanical properties of Inconel 625/TiB2 composite can be significantly influenced by addition of TiB2 particles during SLM. It was found that the long directional columnar grains observed from SLM-processed Inconel 625 were totally changed to fine dendritic matrix due to the addition of TiB2 particles. Moreover, with laser energy density (LED) of 1200 J/m, a Ti, Mo rich interface around TiB2 particles with fine thickness can be observed by FESEM and EDS. The microstructure evolution can be determined by different laser energy density (LED): under 1200 J/m, γ phase in dendrite grains; under 600 J/m, γ phase in combination of dendritic and acicular grains; under 400 J/m, γ phase acicular grains. Under optimized LED 1200 J/m, the dynamic nanohardness (8.62 GPa) and elastic modulus (167 GPa) of SLM-processed Inconel 625/TiB2 composite are higher compared with those of SLM-processed Inconel 625 (3.97 GPa and 135 GPa, respectively).

  6. Lattice Thermal Conductivity of Ultra High Temperature Ceramics (UHTC) ZrB2 and HfB2 from Atomistic Simulations

    NASA Technical Reports Server (NTRS)

    Lawson, John W.; Daw, Murray S.; Bauschlicher, Charles W.

    2012-01-01

    Ultra high temperature ceramics (UHTC) including ZrB2 and HfB2 have a number of properties that make them attractive for applications in extreme environments. One such property is their high thermal conductivity. Computational modeling of these materials will facilitate understanding of fundamental mechanisms, elucidate structure-property relationships, and ultimately accelerate the materials design cycle. Progress in computational modeling of UHTCs however has been limited in part due to the absence of suitable interatomic potentials. Recently, we developed Tersoff style parameterizations of such potentials for both ZrB2 and HfB2 appropriate for atomistic simulations. As an application, Green-Kubo molecular dynamics simulations were performed to evaluate the lattice thermal conductivity for single crystals of ZrB2 and HfB2. The atomic mass difference in these binary compounds leads to oscillations in the time correlation function of the heat current, in contrast to the more typical monotonic decay seen in monoatomic materials such as Silicon, for example. Results at room temperature and at elevated temperatures will be reported.

  7. ZrB2-HfB2 solid solutions as electrode materials for hydrogen reaction in acidic and basic solutions

    DOE PAGES

    Sitler, Steven J.; Raja, Krishnan S.; Charit, Indrajit

    2016-11-09

    Spark plasma sintered transition metal diborides such as HfB2, ZrB2 and their solid solutions were investigated as electrode materials for electrochemical hydrogen evolutions reactions (HER) in 1 M H2SO4 and 1 M NaOH electrolytes. HfB2 and ZrB2 formed complete solid solutions when mixed in 1:1, 1:4, and 4:1 ratios and they were stable in both electrolytes. The HER kinetics of the diborides were slower in the basic solution than in the acidic solutions. The Tafel slopes in 1 M H2SO4 were in the range of 0.15 - 0.18 V/decade except for pure HfB2 which showed a Tafel slope of 0.38more » V/decade. In 1 M NaOH the Tafel slopes were in the range of 0.12 - 0.27 V/decade. The composition of HfxZr1-xB2 solid solutions with x = 0.2 - 0.8, influenced the exchange current densities, overpotentials and Tafel slopes of the HER. As a result, the EIS data were fitted with a porous film equivalent circuit model in order to better understand the HER behavior. In addition, modeling calculations, using density functional theory approach, were carried out to estimate the density of states and band structure of the boride solid solutions.« less

  8. REACTOR FUEL SCAVENGING MEANS

    DOEpatents

    Coffinberry, A.S.

    1962-04-10

    A process for removing fission products from reactor liquid fuel without interfering with the reactor's normal operation or causing a significant change in its fuel composition is described. The process consists of mixing a liquid scavenger alloy composed of about 44 at.% plutoniunm, 33 at.% lanthanum, and 23 at.% nickel or cobalt with a plutonium alloy reactor fuel containing about 3 at.% lanthanum; removing a portion of the fuel and scavenger alloy from the reactor core and replacing it with an equal amount of the fresh scavenger alloy; transferring the portion to a quiescent zone where the scavenger and the plutonium fuel form two distinct liquid layers with the fission products being dissolved in the lanthanum-rich scavenger layer; and the clean plutonium-rich fuel layer being returned to the reactor core. (AEC)

  9. Status of French reactors

    SciTech Connect

    Ballagny, A.

    1997-08-01

    The status of French reactors is reviewed. The ORPHEE and RHF reactors can not be operated with a LEU fuel which would be limited to 4.8 g U/cm{sup 3}. The OSIRIS reactor has already been converted to LEU. It will use U{sub 3}Si{sub 2} as soon as its present stock of UO{sub 2} fuel is used up, at the end of 1994. The decision to close down the SILOE reactor in the near future is not propitious for the start of a conversion process. The REX 2000 reactor, which is expected to be commissioned in 2005, will use LEU (except if the fast neutrons core option is selected). Concerning the end of the HEU fuel cycle, the best option is reprocessing followed by conversion of the reprocessed uranium to LEU.

  10. Development of a liquid hydrogen transfer pump system with MgB2 wires

    NASA Astrophysics Data System (ADS)

    Kajikawa, Kazuhiro; Kuga, Hirotsugu; Inoue, Takuro; Watanabe, Kazuki; Uchida, Yushi; Nakamura, Taketsune; Kobayashi, Hiroaki; Hongo, Motoyuki; Kojima, Takayuki; Taguchi, Hideyuki; Naruo, Yoshihiro; Wakuda, Tsuyoshi; Tanaka, Kazuhide

    An electric pump composed of an MgB2 motor is combined with superconducting level sensors using thin CuNi-sheathed MgB2 wires to transfer liquid hydrogen. An impeller is attached to the lower end of a rotating shaft on the MgB2 motor and covered with an outer casing to form a centrifugal pump. Then, the MgB2 motor and impeller are placed vertically inside a cryostat with an infill of liquid hydrogen. A glass Dewar vessel is prepared to receive the liquid hydrogen transferred from the cryostat containing the MgB2 motor. The MgB2 sensors are used not only to detect the level of liquid hydrogen but also to control the electric pump on the basis of their pre-estimated calibration curves. By using the assembled pump system, the liquid hydrogen is successfully transferred from the cryostat to the glass Dewar vessel via a transfer tube.

  11. Fast creation of dense MgB2 phase in wires made by IMD process

    NASA Astrophysics Data System (ADS)

    Kováč, P.; Hušek, I.; Melišek, T.; Kopera, L.; Kulich, M.

    2016-10-01

    Single-core MgB2 wires have been made by internal magnesium diffusion (IMD) into boron process. Heat treatments were performed at variable periods (4-90 min) for two adjusted temperatures 635 °C and 650 °C, with an overshoot of ≈20 °C after 5 min. Critical currents of differently treated MgB2/Ti/GlidCop wires have been measured and related with the MgB2 layers. The fast creation MgB2 compound has been observed after 8 min annealing at both temperatures and showing the critical current maxima. The less uniform MgB2 containing cracks was created for longer annealing periods (≥10 min), which resulted in lowered critical currents and worsened thermal stability. The fast creation of dense MgB2 allows it to utilize a continual and short heat treatment process for high current density wires made by IMD.

  12. Oxygen interaction with hexagonal OsB2 at high temperature

    DOE PAGES

    Xie, Zhilin; Blair, Richard G.; Orlovskaya, Nina; ...

    2016-08-10

    The stability of ReB2-type hexagonal OsB2 powder at high temperature with oxygen presence has been studied by thermogravimetric analysis, differential scanning calorimetry, SEM, EDS, and high-temperature scanning transmission electron microscopy and XRD. Results of the study revealed that OsB2 ceramics interact readily with oxygen present in reducing atmosphere, especially at high temperature and produces boric acid, which decomposes on the surface of the powder resulting in the formation of boron vacancies in the hexagonal OsB2 lattice as well as changes in the stoichiometry of the compound. It was also found that under low oxygen partial pressure, sintering of OsB2 powdersmore » occurred at a relatively low temperature (900°C). Finally, hexagonal OsB2 ceramic is prone to oxidation and it is very sensitive to oxygen partial pressures, especially at high temperatures.« less

  13. A role of nesfatin-1/NucB2 in dehydration-induced anorexia.

    PubMed

    Yoshimura, Mitsuhiro; Matsuura, Takanori; Ohkubo, Junichi; Maruyama, Takashi; Ishikura, Toru; Hashimoto, Hirofumi; Kakuma, Tetsuya; Mori, Masatomo; Ueta, Yoichi

    2014-07-15

    Nesfatin-1/NucB2, an anorexigenic molecule, is expressed mainly in the hypothalamus, particularly in the supraoptic nucleus (SON) and the paraventricular nucleus (PVN). Nesfatin-1/NucB2 is also expressed in the subfornical organ (SFO). Because the SON and PVN are involved in body fluid regulation, nesfatin-1/NucB2 may be involved in dehydration-induced anorexia. To clarify the effects of endogenous nesfatin-1/NucB2, we studied changes in nesfatin-1/NucB2 mRNA levels in the SFO, SON, and PVN in adult male Wistar rats after exposure to osmotic stimuli by using in situ hybridization histochemistry. Significant increases in nesfatin-1/NucB2 mRNA levels, ∼2- to 3-fold compared with control, were observed in the SFO, SON, and PVN following water deprivation for 48 h, consumption of 2% NaCl hypertonic saline in drinking water for 5 days, and polyethylene glycol-induced hypovolemia. In addition, nesfatin-1/NucB2 expression was increased in response to water deprivation in a time-dependent manner. These changes in nesfatin-1/NucB2 mRNA expression were positively correlated with plasma sodium concentration, plasma osmolality, and total protein levels in all of the examined nuclei. Immunohistochemistry for nesfatin-1/NucB2 revealed that nesfatin-1/NucB2 protein levels were also increased after 48 h of dehydration and attenuated by 24 h of rehydration. Moreover, intracerebroventricular administration of nesfatin-1/NucB2-neutralizing antibody after 48 h of water deprivation resulted in a significant increase in food intake compared with administration of vehicle alone. These results suggested that nesfatin-1/NucB2 is a crucial peptide in dehydration-induced anorexia.

  14. Regulation of Breast Cancer Cell Repression and Differentiation by ErbB2 Ligand.

    DTIC Science & Technology

    1998-03-01

    Overexpression of erbB2 is known to correlate with poor prognosis in breast, ovarian, stomach and lung cancers (31,32,33). However, the clinical significance...Breast Cancer Cell Repression and Differentiation by ErbB2 Ligand PRINCIPAL INVESTIGATOR: C. Richter King, Ph.D. CONTRACTING ORGANIZATION: Georgetown...Final (1 Sep 94 - 28 Feb 98) 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS Regulation of Breast Cancer Cell Repression and Differentiation by ErbB2 Ligand

  15. Improvement of skin wound healing in diabetic mice by kinin B2 receptor blockade.

    PubMed

    Desposito, Dorinne; Chollet, Catherine; Taveau, Christopher; Descamps, Vincent; Alhenc-Gelas, François; Roussel, Ronan; Bouby, Nadine; Waeckel, Ludovic

    2016-01-01

    Impaired skin wound healing is a major medical problem in diabetic subjects. Kinins exert a number of vascular and other actions limiting organ damage in ischaemia or diabetes, but their role in skin injury is unknown. We investigated, through pharmacological manipulation of bradykinin B1 and B2 receptors (B1R and B2R respectively), the role of kinins in wound healing in non-diabetic and diabetic mice. Using two mouse models of diabetes (streptozotocin-induced and db/db mice) and non-diabetic mice, we assessed the effect of kinin receptor activation or inhibition by subtype-selective pharmacological agonists (B1R and B2R) and antagonist (B2R) on healing of experimental skin wounds. We also studied effects of agonists and antagonist on keratinocytes and fibroblasts in vitro. Levels of Bdkrb1 (encoding B1R) and Bdkrb2 (encoding B2R) mRNAs increased 1-2-fold in healthy and wounded diabetic skin compared with in non-diabetic skin. Diabetes delayed wound healing. The B1R agonist had no effect on wound healing. In contrast, the B2R agonist impaired wound repair in both non-diabetic and diabetic mice, inducing skin disorganization and epidermis thickening. In vitro, B2R activation unbalanced fibroblast/keratinocyte proliferation and increased keratinocyte migration. These effects were abolished by co-administration of B2R antagonist. Interestingly, in the two mouse models of diabetes, the B2R antagonist administered alone normalized wound healing. This effect was associated with the induction of Ccl2 (encoding monocyte chemoattractant protein 1)/Tnf (encoding tumour necrosis factor α) mRNAs. Thus stimulation of kinin B2 receptor impairs skin wound healing in mice. B2R activation occurs in the diabetic skin and delays wound healing. B2R blockade improves skin wound healing in diabetic mice and is a potential therapeutic approach to diabetic ulcers.

  16. Preubiquitinated chimeric ErbB2 is constitutively endocytosed and subsequently degraded in lysosomes

    SciTech Connect

    Vuong, Tram Thu; Berger, Christian; Bertelsen, Vibeke; Rødland, Marianne Skeie; Stang, Espen; Madshus, Inger Helene

    2013-02-01

    The oncoprotein ErbB2 is endocytosis-deficient, probably due to its interaction with Heat shock protein 90. We previously demonstrated that clathrin-dependent endocytosis of ErbB2 is induced upon incubation of cells with Ansamycin derivatives, such as geldanamycin and its derivative 17-AAG. Furthermore, we have previously demonstrated that a preubiquitinated chimeric EGFR (EGFR-Ub{sub 4}) is constitutively endocytosed in a clathrin-dependent manner. We now demonstrate that also an ErbB2-Ub{sub 4} chimera is endocytosed constitutively and clathrin-dependently. Upon expression, the ErbB2-Ub{sub 4} was further ubiquitinated, and by Western blotting, we demonstrated the formation of both Lys48-linked and Lys63-linked polyubiquitin chains. ErbB2-Ub{sub 4} was constitutively internalized and eventually sorted to late endosomes and lysosomes where the fusion protein was degraded. ErbB2-Ub{sub 4} was not cleaved prior to internalization. Interestingly, over-expression of Ubiquitin Interaction Motif-containing dominant negative fragments of the clathrin adaptor proteins epsin1 and Eps15 negatively affected endocytosis of ErbB2. Altogether, this argues that ubiquitination is sufficient to induce clathrin-mediated endocytosis and lysosomal degradation of the otherwise plasma membrane localized ErbB2. Also, it appears that C-terminal cleavage is not required for endocytosis. -- Highlights: ► A chimera containing ErbB2 and a tetra-Ubiquitin chain internalizes constitutively. ► Receptor fragmentation is not required for endocytosis of ErbB2. ► Ubiquitination is sufficient to induce endocytosis and degradation of ErbB2. ► ErbB2-Ub4 is internalized clathrin-dependently.

  17. Development of Specific Inhibitors for Breast Cancer-Associated Variants of ErbB2

    DTIC Science & Technology

    2015-10-01

    methods to identify compounds that can selectively target and inhibit those ErbB2 mutants verified as active. The third objective is to...experimentally test a subset of the most promising compounds for the ability to experimentally inhibit specific ErbB2 mutants . The research team consists of two...screening methods to identify compounds that can selectively target and inhibit those ErbB2 mutants verified as active. The third objective is to

  18. Al-doped MgB2 materials studied using electron paramagnetic resonance and Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Bateni, Ali; Erdem, Emre; Repp, Sergej; Weber, Stefan; Somer, Mehmet

    2016-05-01

    Undoped and aluminum (Al) doped magnesium diboride (MgB2) samples were synthesized using a high-temperature solid-state synthesis method. The microscopic defect structures of Al-doped MgB2 samples were systematically investigated using X-ray powder diffraction, Raman spectroscopy, and electron paramagnetic resonance. It was found that Mg-vacancies are responsible for defect-induced peculiarities in MgB2. Above a certain level of Al doping, enhanced conductive properties of MgB2 disappear due to filling of vacancies or trapping of Al in Mg-related vacancy sites.

  19. Superconducting MgB2 flowers: growth mechanism and their superconducting properties

    NASA Astrophysics Data System (ADS)

    Seong, Won Kyung; Ranot, Mahipal; Lee, Ji Yeong; Yang, Cheol-Woong; Lee, Jae Hak; Oh, Young Hoon; Ahn, Jae-Pyoung; Kang, Won Nam

    2016-04-01

    We report for the first time the growth and the systematic study of the growth mechanism for flower-like MgB2 structures fabricated on the substrates for solid-state electronics by the hybrid physical-chemical vapor deposition (HPCVD) technique. The MgB2 flower has a width of 30 μm and a height of 10 μm. The superconductivity of MgB2 flowers was confirmed by a magnetization measurement, and the transition temperature is 39 K, which is comparable with high-quality bulk samples. The excellent current-carrying capability was demonstrated by MgB2 flowers. To understand the nucleation and growth mechanism of MgB2 flowers a very systematic study was performed by a high-resolution transmission electron microscope (HRTEM) and atom probe (AP) microscopy. The HRTEM revealed that the seed grain of a MgB2 flower has a [101¯0] direction, and the flower is composed of micro-columnar MgB2 grains having pyramidal tips and which are grown along the (0001) plane. A clear understanding of the growth mechanism for MgB2 flowers could lead to the growth of other low-dimensional MgB2 structures for superconducting electronic devices.

  20. Single-crystal X-ray and powder neutron diffraction of ThB 2C (ThB 2C-type)

    NASA Astrophysics Data System (ADS)

    Rogl, Peter; Fischer, Peter

    1989-02-01

    The crystal structure of ThB 2C was determined using single-crystal X-ray and powder neutron diffraction data. ThB 2C crystallizes in the rhombohedral space group R overline3m with a = 0.66761(23), c = 1.13760(31) nm, {c}/{a} = 1.704, V = 0.4391 nm 3, Z = 9 . X-ray intensity data were obtained from a four-circle diffractometer; the structure was solved by Patterson methods and refined by full-matrix least-squares calculation. R = {∑|ΔF|}/{∑|F o| } = 0.034 for an asymmetric set of 219 independent reflections (| Fo| > 2 σ( Fo)). Precise nonmetal atom parameters and bond distances have been derived from room-temperature neutron powder diffraction data employing the Rietveld-Young profile analysis method. The reliability value of the neutron refinement was RI = 0.067. The crystal structure of ThB 2C is a new structure type with slightly puckered 6 3-Th-metal layers alternating with nonmetal layers each composed of hexagons of boron atoms, the hexagons being linked by carbon atoms. Boron atoms are in a triangular prismatic metal surrounding of a tetrakaidekahedral coordination |Th 6B 2C 1|B, whereas carbon atoms occupy the center points of quadratic bipyramids |Th 4B 2|C. The crystal structure of ThB 2C derives from the AlB 2-type structure with carbon atoms entering the boron nets to form a 2∞ - (6B) · (6B(3C)) 2 layer.

  1. Slurry reactor design studies

    SciTech Connect

    Fox, J.M.; Degen, B.D.; Cady, G.; Deslate, F.D.; Summers, R.L. ); Akgerman, A. ); Smith, J.M. )

    1990-06-01

    The objective of these studies was to perform a realistic evaluation of the relative costs of tublar-fixed-bed and slurry reactors for methanol, mixed alcohols and Fischer-Tropsch syntheses under conditions where they would realistically be expected to operate. The slurry Fischer-Tropsch reactor was, therefore, operated at low H{sub 2}/CO ratio on gas directly from a Shell gasifier. The fixed-bed reactor was operated on 2.0 H{sub 2}/CO ratio gas after adjustment by shift and CO{sub 2} removal. Every attempt was made to give each reactor the benefit of its optimum design condition and correlations were developed to extend the models beyond the range of the experimental pilot plant data. For the methanol design, comparisons were made for a recycle plant with high methanol yield, this being the standard design condition. It is recognized that this is not necessarily the optimum application for the slurry reactor, which is being proposed for a once-through operation, coproducing methanol and power. Consideration is also given to the applicability of the slurry reactor to mixed alcohols, based on conditions provided by Lurgi for an Octamix{trademark} plant using their standard tubular-fixed reactor technology. 7 figs., 26 tabs.

  2. Nuclear reactor control column

    DOEpatents

    Bachovchin, Dennis M.

    1982-01-01

    The nuclear reactor control column comprises a column disposed within the nuclear reactor core having a variable cross-section hollow channel and containing balls whose vertical location is determined by the flow of the reactor coolant through the column. The control column is divided into three basic sections wherein each of the sections has a different cross-sectional area. The uppermost section of the control column has the greatest cross-sectional area, the intermediate section of the control column has the smallest cross-sectional area, and the lowermost section of the control column has the intermediate cross-sectional area. In this manner, the area of the uppermost section can be established such that when the reactor coolant is flowing under normal conditions therethrough, the absorber balls will be lifted and suspended in a fluidized bed manner in the upper section. However, when the reactor coolant flow falls below a predetermined value, the absorber balls will fall through the intermediate section and into the lowermost section, thereby reducing the reactivity of the reactor core and shutting down the reactor.

  3. Reactor Safety Research Programs

    SciTech Connect

    Edler, S. K.

    1981-07-01

    This document summarizes the work performed by Pacific Northwest Laboratory (PNL) from January 1 through March 31, 1981, for the Division of Reactor Safety Research within the U.S. Nuclear Regulatory Commission (NRC). Evaluations of nondestructive examination (NDE) techniques and instrumentation are reported; areas of investigation include demonstrating the feasibility of determining the strength of structural graphite, evaluating the feasibility of detecting and analyzing flaw growth in reactor pressure boundary systems, examining NDE reliability and probabilistic fracture mechanics, and assessing the integrity of pressurized water reactor (PWR) steam generator tubes where service-induced degradation has been indicated. Experimental data and analytical models are being provided to aid in decision-making regarding pipeto- pipe impacts following postulated breaks in high-energy fluid system piping. Core thermal models are being developed to provide better digital codes to compute the behavior of full-scale reactor systems under postulated accident conditions. Fuel assemblies and analytical support are being provided for experimental programs at other facilities. These programs include loss-ofcoolant accident (LOCA) simulation tests at the NRU reactor, Chalk River, Canada; fuel rod deformation, severe fuel damage, and postaccident coolability tests for the ESSOR reactor Super Sara Test Program, Ispra, Italy; the instrumented fuel assembly irradiation program at Halden, Norway; and experimental programs at the Power Burst Facility, Idaho National Engineering Laboratory (INEL). These programs will provide data for computer modeling of reactor system and fuel performance during various abnormal operating conditions.

  4. REACTOR BASE, SOUTHEAST CORNER. INTERIOR WILL CONTAIN REACTOR TANK, COOLING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    REACTOR BASE, SOUTHEAST CORNER. INTERIOR WILL CONTAIN REACTOR TANK, COOLING WATER PIPES, COOLING AIR DUCTS, AND SHIELDING. INL NEGATIVE NO. 776. Unknown Photographer, 10/1950 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  5. Aspirin response: Differences in serum thromboxane B2 levels between clinical studies.

    PubMed

    Brun, Charlotte; Daali, Youssef; Combescure, Christophe; Zufferey, Anne; Michelson, Alan D; Fontana, Pierre; Reny, Jean-Luc; Frelinger, Andrew L

    2016-01-01

    Serum thromboxane B2 (TxB2) is a specific marker of platelet inhibition by aspirin. Yet, TxB2 levels differ by up to 10-fold between some aspirin-treated patient cohorts. This study aimed to identify factors responsible for differences in serum TxB2 between cohorts in the ADRIE study (n = 657) and the BOSTON study (n = 678) of aspirin-treated cardiovascular patients originally tested with different ELISA assays. TxB2 levels were assessed in representative subgroups of the two cohorts (34 samples in BOSTON and 39 in ADRIE) by both ELISAs, as well as liquid chromatography and tandem mass spectroscopy (MS). A multivariate analysis was performed on the whole cohort database to identify determinants of the difference of TxB2 levels between cohorts. There was no systematic bias between the original ELISA TxB2 values and the MS values and the median difference was small, 0.12 ng/ml, thus not explaining the difference between median TxB2 levels in the two study populations (7 and 0.6 ng/ml in the ADRIE and BOSTON studies, respectively). In the combined dataset of the ADRIE and BOSTON cohorts (n = 1342), body mass index, age, gender, aspirin dose, time from aspirin intake to blood draw, NSAID intake, platelet count and C-reactive protein were significantly associated with TxB2 levels. After adjustment for patient characteristics, the difference between cohorts did not decrease. Unexplained differences in serum TxB2 levels in different populations of aspirin-treated cardiovascular patients suggest that further studies are needed to confirm the role of serum TxB2 level as a prognostic factor or rather as a marker of therapeutic observance.

  6. Review of magnetic features observed in (A,A')Ni 2B 2C solid solutions

    NASA Astrophysics Data System (ADS)

    Kuznietz, Moshe; Gonçalves, António P.; Almeida, Manuel

    2002-08-01

    The nickel-borocarbides ANi 2B 2C [A=Y, Ln (lanthanide), An(actinide)], crystallizing in the body-centred tetragonal LuNi 2B 2C-type structure, are classified according to the existence or coexistence of superconducting and antiferromagnetic states (AF). The magnetic features observed in polycrystalline (A,A')Ni 2B 2C solid solutions, adopting the same crystal structure, are reviewed and discussed. Published data on the magnetism in (A,Ln)Ni 2B 2C systems (ANi 2B 2C nonmagnetic, A=Y,La,Lu) indicate a gradual rise in the threshold content, x( m), in (Y 1- xLn x)Ni 2B 2C (Ln=Gd,Tb,Dy,Ho,Er) for the establishment of AF states. (A,A')Ni 2B 2C systems with magnetic end compounds show gradual variation in magnetic features when A and A' are both heavy Ln. The behaviour of (A,A')Ni 2B 2C systems of light A (Pr or U) and heavy A' (Dy or Tm) depends on the magnetic structures of the end compounds. In intermediate compositions, incomplete moment compensation in (Pr,Dy)Ni 2B 2C decreases TN, while different moment directions in the end compounds in (U,Dy)Ni 2B 2C lead to a directional frustration of ordered moments. Such a frustration in (U,Tm)Ni 2B 2C is related to different magnetic structures of the end compounds.

  7. Fast Breeder Reactor studies

    SciTech Connect

    Till, C.E.; Chang, Y.I.; Kittel, J.H.; Fauske, H.K.; Lineberry, M.J.; Stevenson, M.G.; Amundson, P.I.; Dance, K.D.

    1980-07-01

    This report is a compilation of Fast Breeder Reactor (FBR) resource documents prepared to provide the technical basis for the US contribution to the International Nuclear Fuel Cycle Evaluation. The eight separate parts deal with the alternative fast breeder reactor fuel cycles in terms of energy demand, resource base, technical potential and current status, safety, proliferation resistance, deployment, and nuclear safeguards. An Annex compares the cost of decommissioning light-water and fast breeder reactors. Separate abstracts are included for each of the parts.

  8. REACTOR CONTROL SYSTEM

    DOEpatents

    MacNeill, J.H.; Estabrook, J.Y.

    1960-05-10

    A reactor control system including a continuous tape passing through a first coolant passageway, over idler rollers, back through another parallel passageway, and over motor-driven rollers is described. Discrete portions of fuel or poison are carried on two opposed active sections of the tape. Driving the tape in forward or reverse directions causes both active sections to be simultaneously inserted or withdrawn uniformly, tending to maintain a more uniform flux within the reactor. The system is particularly useful in mobile reactors, where reduced inertial resistance to control rod movement is important.

  9. NUCLEAR REACTOR FUEL SYSTEMS

    DOEpatents

    Thamer, B.J.; Bidwell, R.M.; Hammond, R.P.

    1959-09-15

    Homogeneous reactor fuel solutions are reported which provide automatic recombination of radiolytic gases and exhibit large thermal expansion characteristics, thereby providing stability at high temperatures and enabling reactor operation without the necessity of apparatus to recombine gases formed by the radiolytic dissociation of water in the fuel and without the necessity of liquid fuel handling outside the reactor vessel except for recovery processes. The fuels consist of phosphoric acid and water solutions of enriched uranium, wherein the uranium is in either the hexavalent or tetravalent state.

  10. COOLED NEUTRONIC REACTOR

    DOEpatents

    Binner, C.R.; Wilkie, C.B.

    1958-03-18

    This patent relates to a design for a reactor of the type in which a fluid coolant is flowed through the active portion of the reactor. This design provides for the cooling of the shielding material as well as the reactor core by the same fluid coolant. The core structure is a solid moderator having coolant channels in which are disposed the fuel elements in rod or slug form. The coolant fluid enters the chamber in the shield, in which the core is located, passes over the inner surface of said chamber, enters the core structure at the center, passes through the coolant channels over the fuel elements and out through exhaust ducts.

  11. Microfluidic electrochemical reactors

    DOEpatents

    Nuzzo, Ralph G [Champaign, IL; Mitrovski, Svetlana M [Urbana, IL

    2011-03-22

    A microfluidic electrochemical reactor includes an electrode and one or more microfluidic channels on the electrode, where the microfluidic channels are covered with a membrane containing a gas permeable polymer. The distance between the electrode and the membrane is less than 500 micrometers. The microfluidic electrochemical reactor can provide for increased reaction rates in electrochemical reactions using a gaseous reactant, as compared to conventional electrochemical cells. Microfluidic electrochemical reactors can be incorporated into devices for applications such as fuel cells, electrochemical analysis, microfluidic actuation, pH gradient formation.

  12. Nuclear reactor reflector

    DOEpatents

    Hopkins, Ronald J.; Land, John T.; Misvel, Michael C.

    1994-01-01

    A nuclear reactor reflector is disclosed that comprises a stack of reflector blocks with vertical water flow passages to cool the reflector. The interface between blocks is opposite support points for reactor fuel rods. Water flows between the reflector and the reactor barrel from passages in a bottom block. The top block contains a flange to limit this flow and the flange has a slot to receive an alignment pin that is welded to the barrel. The pin is held in the slot by two removable shims. Alignment bars extend the length of the stack in slots machined in each block when the stack is assembled.

  13. Nuclear reactor reflector

    DOEpatents

    Hopkins, R.J.; Land, J.T.; Misvel, M.C.

    1994-06-07

    A nuclear reactor reflector is disclosed that comprises a stack of reflector blocks with vertical water flow passages to cool the reflector. The interface between blocks is opposite support points for reactor fuel rods. Water flows between the reflector and the reactor barrel from passages in a bottom block. The top block contains a flange to limit this flow and the flange has a slot to receive an alignment pin that is welded to the barrel. The pin is held in the slot by two removable shims. Alignment bars extend the length of the stack in slots machined in each block when the stack is assembled. 12 figs.

  14. NEUTRONIC REACTOR CONTROL

    DOEpatents

    Metcalf, H.E.

    1958-10-14

    Methods of controlling reactors are presented. Specifically, a plurality of neutron absorber members are adjustably disposed in the reactor core at different distances from the center thereof. The absorber members extend into the core from opposite faces thereof and are operated by motive means coupled in a manner to simultaneously withdraw at least one of the absorber members while inserting one of the other absorber members. This feature effects fine control of the neutron reproduction ratio by varying the total volume of the reactor effective in developing the neutronic reaction.

  15. CONTROL FOR NEUTRONIC REACTOR

    DOEpatents

    Lichtenberger, H.V.; Cameron, R.A.

    1959-03-31

    S>A control rod operating device in a nuclear reactor of the type in which the control rod is gradually withdrawn from the reactor to a position desired during stable operation is described. The apparatus is comprised essentially of a stop member movable in the direction of withdrawal of the control rod, a follower on the control rod engageable with the stop and means urging the follower against the stop in the direction of withdrawal. A means responsive to disengagement of the follower from the stop is provided for actuating the control rod to return to the reactor shut-down position.

  16. Spherical torus fusion reactor

    DOEpatents

    Martin Peng, Y.K.M.

    1985-10-03

    The object of this invention is to provide a compact torus fusion reactor with dramatic simplification of plasma confinement design. Another object of this invention is to provide a compact torus fusion reactor with low magnetic field and small aspect ratio stable plasma confinement. In accordance with the principles of this invention there is provided a compact toroidal-type plasma confinement fusion reactor in which only the indispensable components inboard of a tokamak type of plasma confinement region, mainly a current conducting medium which carries electrical current for producing a toroidal magnet confinement field about the toroidal plasma region, are retained.

  17. ZrB2 thin films deposited on GaN(0001) by magnetron sputtering from a ZrB2 target

    NASA Astrophysics Data System (ADS)

    Tengdelius, Lina; Lu, Jun; Forsberg, Urban; Li, Xun; Hultman, Lars; Janzén, Erik; Högberg, Hans

    2016-11-01

    ZrB2 films were deposited on 900 °C-preheated or non-preheated GaN(0001) surfaces by direct current magnetron sputtering from a compound target. Analytical transmission electron microscopy and scanning transmission electron microscopy with energy dispersive X-ray spectroscopy and electron energy loss spectroscopy revealed a 0001 fiber textured ZrB2 film growth following the formation of a 2 nm thick amorphous BN layer onto the GaN(0001) at a substrate temperature of 900 °C. The amorphous BN layer remains when the substrate temperature is lowered to 500 °C or when the preheating step is removed from the process and results in the growth of polycrystalline ZrB2 films. The ZrB2 growth phenomena on GaN(0001) is compared to on 4H-SiC(0001), Si(111), and Al2O3(0001) substrates, which yield epitaxial film growth. The decomposition of the GaN surface during vacuum processing during BN interfacial layer formation is found to impede epitaxial growth of ZrB2.

  18. Improved Serodiagnosis of Cystic Echinococcosis Using the New Recombinant 2B2t Antigen

    PubMed Central

    Hernández-González, Ana; Santivañez, Saúl; García, Héctor H.; Rodríguez, Silvia; Muñoz, Santiago; Ramos, Guillermo; Orduña, Antonio; Siles-Lucas, Mar

    2012-01-01

    A standardized test for the serodiagnosis of human cystic echinococcosis (CE) is still needed, because of the low specificity and sensitivity of the currently available commercial tools and the lack of proper evaluation of the existing recombinant antigens. In a previous work, we defined the new ELISA-B2t diagnostic tool for the detection of specific IgGs in CE patients, which showed high sensitivity and specificity, and was useful in monitoring the clinical evolution of surgically treated CE patients. Nevertheless, this recombinant antigen gave rise to false-negative results in a percentage of CE patients. Therefore, in an attempt to improve its sensitivity, we constructed B2t-derived recombinant antigens with two, four and eight tandem repeat of B2t units, and tested them by ELISA on serum samples of CE patients and patients with related parasites. The best diagnostic values were obtained with the two tandem repeat 2B2t antigen. The influence of several clinical variables on the performance of the tests was also evaluated. Finally, the diagnostic performance of the 2B2t-ELISA was compared with that of an indirect haemagglutination commercial test. The 2B2t recombinant antigen performed better than the HF and B2t antigens, and the IHA commercial kit. Therefore, this new 2B2t-ELISA is a promising candidate test for the serodiagnosis of CE in clinical settings. PMID:22802975

  19. 26 CFR 31.3302(b)-2 - Proof of additional credit under section 3302(b).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 15 2010-04-01 2010-04-01 false Proof of additional credit under section 3302(b). 31.3302(b)-2 Section 31.3302(b)-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) EMPLOYMENT TAXES AND COLLECTION OF INCOME TAX AT SOURCE EMPLOYMENT TAXES AND COLLECTION OF INCOME TAX AT SOURCE...

  20. 29 CFR 783.26 - The section 6(b)(2) minimum wage requirement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false The section 6(b)(2) minimum wage requirement. 783.26... The section 6(b)(2) minimum wage requirement. Section 6(b), with paragraph (2) thereof, requires the... prescribed by” paragraph (1) of the subsection is the minimum wage rate applicable according to the...

  1. 29 CFR 783.26 - The section 6(b)(2) minimum wage requirement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 3 2012-07-01 2012-07-01 false The section 6(b)(2) minimum wage requirement. 783.26... The section 6(b)(2) minimum wage requirement. Section 6(b), with paragraph (2) thereof, requires the... prescribed by” paragraph (1) of the subsection is the minimum wage rate applicable according to the...

  2. 29 CFR 783.26 - The section 6(b)(2) minimum wage requirement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false The section 6(b)(2) minimum wage requirement. 783.26... The section 6(b)(2) minimum wage requirement. Section 6(b), with paragraph (2) thereof, requires the... prescribed by” paragraph (1) of the subsection is the minimum wage rate applicable according to the...

  3. 29 CFR 783.26 - The section 6(b)(2) minimum wage requirement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 3 2014-07-01 2014-07-01 false The section 6(b)(2) minimum wage requirement. 783.26... The section 6(b)(2) minimum wage requirement. Section 6(b), with paragraph (2) thereof, requires the... prescribed by” paragraph (1) of the subsection is the minimum wage rate applicable according to the...

  4. 29 CFR 783.26 - The section 6(b)(2) minimum wage requirement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 3 2013-07-01 2013-07-01 false The section 6(b)(2) minimum wage requirement. 783.26... The section 6(b)(2) minimum wage requirement. Section 6(b), with paragraph (2) thereof, requires the... prescribed by” paragraph (1) of the subsection is the minimum wage rate applicable according to the...

  5. MgB2 superconductors with abnormally improved Jc sintered after autoxidation of milled original powders

    NASA Astrophysics Data System (ADS)

    Ma, Zongqing; Liu, Yongchang; Huo, Jie; Gao, Zhiming

    2009-12-01

    An autoxidation treatment of short-time milled original powders was introduced for the synthesis of MgB2 superconductors and the critical current density Jc of the sintered MgB2 bulks was measured. It is unusually found that the undoped MgB2 bulks sintered with those autoxided milled original powder exhibit abnormally excellent Jc (above 1×104 A cm-2 even at 3.5 T, 20 K). Combined with the investigation of sintering process, it was found that the autoxidation treatment of the milled powders affects the subsequent sintering process dramatically and finally leads to the formation of MgB2 nanocrystalline with lots of dislocation and self-generated MgO nanoinclusions embedded in them. This unique microstructure brought up a significant improvement of Jc at high fields. Besides, the formation mechanism of this unique microstructure during the sintering process was also discussed in detail. It suggested that the MgO preformed by the reaction between Mg and B2O3 in the interface between Mg particles and B particles might serve as nuclei for the heterogeneous nucleation of the MgB2 phase and finally be included in the MgB2 grains as they grew up. The present method provides possible windows for the development of practical MgB2 superconductors without adopting expensive nanodopants.

  6. 22 CFR 9b.2 - Press correspondents employed by United States media organizations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... news media organizations; (3) Date of birth; (4) Place of birth; (5) Sex; (6) Citizenship; (7) Social... media organizations. 9b.2 Section 9b.2 Foreign Relations DEPARTMENT OF STATE GENERAL REGULATIONS... media organizations. In order to obtain a Department of State press building pass, press...

  7. 26 CFR 31.3406(b)(2)-3 - Window transactions.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 15 2013-04-01 2013-04-01 false Window transactions. 31.3406(b)(2)-3 Section 31... SOURCE Collection of Income Tax at Source § 31.3406(b)(2)-3 Window transactions. (a) Requirement to backup withhold. Withholding under section 3406 applies to a window transaction (as defined in...

  8. 26 CFR 31.3406(b)(2)-3 - Window transactions.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 15 2011-04-01 2011-04-01 false Window transactions. 31.3406(b)(2)-3 Section 31... SOURCE Collection of Income Tax at Source § 31.3406(b)(2)-3 Window transactions. (a) Requirement to backup withhold. Withholding under section 3406 applies to a window transaction (as defined in...

  9. 26 CFR 31.3406(b)(2)-3 - Window transactions.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 15 2014-04-01 2014-04-01 false Window transactions. 31.3406(b)(2)-3 Section 31... SOURCE Collection of Income Tax at Source § 31.3406(b)(2)-3 Window transactions. (a) Requirement to backup withhold. Withholding under section 3406 applies to a window transaction (as defined in...

  10. 26 CFR 31.3406(b)(2)-3 - Window transactions.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 15 2012-04-01 2012-04-01 false Window transactions. 31.3406(b)(2)-3 Section 31... SOURCE Collection of Income Tax at Source § 31.3406(b)(2)-3 Window transactions. (a) Requirement to backup withhold. Withholding under section 3406 applies to a window transaction (as defined in...

  11. 26 CFR 31.3406(b)(2)-3 - Window transactions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 15 2010-04-01 2010-04-01 false Window transactions. 31.3406(b)(2)-3 Section 31... SOURCE Collection of Income Tax at Source § 31.3406(b)(2)-3 Window transactions. (a) Requirement to backup withhold. Withholding under section 3406 applies to a window transaction (as defined in...

  12. 26 CFR 1.6038B-2 - Reporting of certain transfers to foreign partnerships.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... partnerships. 1.6038B-2 Section 1.6038B-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... certain transfers to foreign partnerships. (a) Reporting requirements—(1) Requirement to report transfers. A United States person that transfers property to a foreign partnership in a contribution...

  13. 26 CFR 1.6038B-2 - Reporting of certain transfers to foreign partnerships.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... partnerships. 1.6038B-2 Section 1.6038B-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... certain transfers to foreign partnerships. (a) Reporting requirements—(1) Requirement to report transfers. A United States person that transfers property to a foreign partnership in a contribution...

  14. High Upper Critical Field and Irreversibility Field in MgB2 Coated-Conductor Fibers

    DTIC Science & Technology

    2016-06-13

    for MgB2 by sputtering on Hastelloy 9 and by electroplating on stainless steel .10 These works have gener- ated Hc2 and Hirr values similar to those of...wires because it is brittle and costly, MgB2 coatings can be made on inexpensive and strong metallic wires such as stainless steel .10,26 Therefore

  15. Antibacterial Peptide CecropinB2 Production via Various Host and Construct Systems.

    PubMed

    Lai, Wei-Shiang; Kan, Shu-Chen; Lin, Chia-Chi; Shieh, Chwen-Jen; Liu, Yung-Chuan

    2016-01-16

    Cecropin is a cationic antibacterial peptide composed of 35-39 residues. This peptide has been identified as possessing strong antibacterial activity and low toxicity against eukaryotic cells, and it has been claimed that some types of the cecropin family of peptides are capable of killing cancer cells. In this study, the host effect of cloning antibacterial peptide cecropinB2 was investigated. Three different host expression systems were chosen, i.e., Escherichia coli, Bacillus subtilis and Pichia pastoris. Two gene constructs, cecropinB2 (cecB2) and intein-cecropinB2 (INT-cecB2), were applied. Signal peptide and propeptide from Armigeres subalbatus were also attached to the gene construct. The results showed that the best host for cloning cecropinB2 was P. pastoris SMD1168 harboring the gene of pGAPzαC-prepro-cecB2 via Western blot confirmation. The cecropinB2 that was purified using immobilized-metal affinity chromatography resin showed strong antibacterial activity against the Gram-negative strains, including the multi-drug-resistant bacteria Acinetobacter baumannii.

  16. 22 CFR 9b.2 - Press correspondents employed by United States media organizations.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... news media organizations; (3) Date of birth; (4) Place of birth; (5) Sex; (6) Citizenship; (7) Social... media organizations. 9b.2 Section 9b.2 Foreign Relations DEPARTMENT OF STATE GENERAL REGULATIONS... media organizations. In order to obtain a Department of State press building pass, press...

  17. 22 CFR 9b.2 - Press correspondents employed by United States media organizations.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... news media organizations; (3) Date of birth; (4) Place of birth; (5) Sex; (6) Citizenship; (7) Social... media organizations. 9b.2 Section 9b.2 Foreign Relations DEPARTMENT OF STATE GENERAL REGULATIONS... media organizations. In order to obtain a Department of State press building pass, press...

  18. 22 CFR 9b.2 - Press correspondents employed by United States media organizations.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... news media organizations; (3) Date of birth; (4) Place of birth; (5) Sex; (6) Citizenship; (7) Social... media organizations. 9b.2 Section 9b.2 Foreign Relations DEPARTMENT OF STATE GENERAL REGULATIONS... media organizations. In order to obtain a Department of State press building pass, press...

  19. 22 CFR 9b.2 - Press correspondents employed by United States media organizations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... news media organizations; (3) Date of birth; (4) Place of birth; (5) Sex; (6) Citizenship; (7) Social... media organizations. 9b.2 Section 9b.2 Foreign Relations DEPARTMENT OF STATE GENERAL REGULATIONS... media organizations. In order to obtain a Department of State press building pass, press...

  20. 17 CFR 270.24b-2 - Filing copies of sales literature.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Filing copies of sales literature. 270.24b-2 Section 270.24b-2 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION... literature. Copies of material filed with the Commission for the sole purpose of complying with section...

  1. SerpinB2 is critical to Th2 immunity against enteric nematode infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    SerpinB2, a member of the serine protease inhibitor family, is expressed by macrophages and up-regulated significantly by inflammation. Recent studies implicated a role for SerpinB2 in the control of Th1 and Th2 immune responses, but the mechanisms of these effects are unknown. In the current study...

  2. A Decompositional Approach to Executing Quality Data Model Algorithms on the i2b2 Platform

    PubMed Central

    Mo, Huan; Jiang, Guoqian; Pacheco, Jennifer A.; Kiefer, Richard; Rasmussen, Luke V.; Pathak, Jyotishman; Denny, Joshua C.; Thompson, William K.

    2016-01-01

    The Quality Data Model (QDM) is an established standard for representing electronic clinical quality measures on electronic health record (EHR) repositories. The Informatics for Integrated Biology and the Bedside (i2b2) is a widely used platform for implementing clinical data repositories. However, translation from QDM to i2b2 is challenging, since QDM allows for complex queries beyond the capability of single i2b2 messages. We have developed an approach to decompose complex QDM algorithms into workflows of single i2b2 messages, and execute them on the KNIME data analytics platform. Each workflow operation module is composed of parameter lists, a template for the i2b2 message, an mechanism to create parameter updates, and a web service call to i2b2. The communication between workflow modules relies on passing keys ofi2b2 result sets. As a demonstration of validity, we describe the implementation and execution of a type 2 diabetes mellitus phenotype algorithm against an i2b2 data repository. PMID:27570665

  3. Assessment of vitamin B2 status in performance athletes of various types of sports.

    PubMed

    Rokitzki, L; Sagredos, A; Keck, E; Sauer, B; Keul, J

    1994-02-01

    To determine the vitamin B2 supply, 62 athletes in various types of sports and 16 non-athletes were examined, using a weighed food record (7-day), alpha-EGR determination, microbiological blood, and HPLC urinary measurements. If the guidelines of 1.5 or 1.7 mg/day vitamin B2 or 0.6 mg/4,184 kJ (GRDA) are defined for adequate status, all sports groups (M +/- SEM) are above this level. The vitamin B2 blood concentrations show a range (mean) from 303-372 nmol/liter, which indicates that more than 90% of the athletes are above the reference value of 327 nmol/liter (mean). There is a correlation of r = 0.49 between the vitamin B2 intake (mean over 7 days) and the vitamin B2 blood level. Determination of vitamin B2 blood concentration is characterized by good precision (C.V. +/- 3.2%) and recovery (95.7%). The enzyme activation measurement (alpha-EGR) shows that all of the athletes are below the alpha-EGR reference value of < 1.50 (good supply). No significant correlations could be determined between alpha-EGR and vitamin B2 intake, blood concentrations, and urinary excretion. The measurement also shows high precision (C.V. 1.7%). The Vitamin B2 excretion in urine (mumol/g Cr.) was higher than the reference values for non-athletes in more than 90% of the athletes. There is a correlation of r = 0.89 between the vitamin B2 intake on the last day (Day 7) of the food record and the riboflavin excretion, and between vitamin B2 in blood and urinary excretion of r = 0.52. The C.V. of vitamin B2 urinary measurement using HPLC is 2.5%, with recovery of 98.2%. Combined measurement of vitamin B2 intake, blood concentration, and urine excretion appears to be a suitable procedure for determining the vitamin B2 status. Most of the performance athletes were sufficiently supplied with vitamin B2, compared to the reference values for non-athletes.

  4. Downregulation of kinin B1 receptor function by B2 receptor heterodimerization and signaling.

    PubMed

    Zhang, Xianming; Brovkovych, Viktor; Zhang, Yongkang; Tan, Fulong; Skidgel, Randal A

    2015-01-01

    Signaling through the G protein-coupled kinin receptors B1 (kB1R) and B2 (kB2R) plays a critical role in inflammatory responses mediated by activation of the kallikrein-kinin system. The kB2R is constitutively expressed and rapidly desensitized in response to agonist whereas kB1R expression is upregulated by inflammatory stimuli and it is resistant to internalization and desensitization. Here we show that the kB1R heterodimerizes with kB2Rs in co-transfected HEK293 cells and natively expressing endothelial cells, resulting in significant internalization and desensitization of the kB1R response in cells pre-treated with kB2R agonist. However, pre-treatment of cells with kB1R agonist did not affect subsequent kB2R responses. Agonists of other G protein-coupled receptors (thrombin, lysophosphatidic acid) had no effect on a subsequent kB1R response. The loss of kB1R response after pretreatment with kB2R agonist was partially reversed with kB2R mutant Y129S, which blocks kB2R signaling without affecting endocytosis, or T342A, which signals like wild type but is not endocytosed. Co-endocytosis of the kB1R with kB2R was dependent on β-arrestin and clathrin-coated pits but not caveolae. The sorting pathway of kB1R and kB2R after endocytosis differed as recycling of kB1R to the cell surface was much slower than that of kB2R. In cytokine-treated human lung microvascular endothelial cells, pre-treatment with kB2R agonist inhibited kB1R-mediated increase in transendothelial electrical resistance (TER) caused by kB1R stimulation (to generate nitric oxide) and blocked the profound drop in TER caused by kB1R activation in the presence of pyrogallol (a superoxide generator). Thus, kB1R function can be downregulated by kB2R co-endocytosis and signaling, suggesting new approaches to control kB1R signaling in pathological conditions.

  5. i2b2t2: Unlocking Visualization for Clinical Research

    PubMed Central

    Harris, Daniel R.; Henderson, Darren W.

    2016-01-01

    We introduce a tool that extracts clinical data sets and provides visualizations from clinical data warehouses that use the Informatics for Integrating Biology and the Bedside (i2b2) query tool. Our tool, i2b2t2 (i2b2 to Tableau), can extract and visualize any i2b2 query into a portable format that researchers can easily explore without needing a highly technical or statistical background. This user-friendly format provides a quick visual summary of the queried population and is easily extendable to develop more intricate and robust visualizations. Extraction and visualization can be provided as a service by clinical data warehouses to expedite the release of data sets for research. i2b2t2 also encourages visualization as a self-service; a motivated researcher can develop custom visualizations for exploration or publication. PMID:27570658

  6. Dirac State in the FeB2 Monolayer with Graphene-Like Boron Sheet.

    PubMed

    Zhang, Haijun; Li, Yafei; Hou, Jianhou; Du, Aijun; Chen, Zhongfang

    2016-10-12

    By introducing the commonly utilized Fe atoms into a two-dimensional (2D) honeycomb boron network, we theoretically designed a new Dirac material of FeB2 monolayer with a Fermi velocity in the same order of graphene. The electron transfer from Fe atoms to B networks not only effectively stabilizes the FeB2 networks but also leads to the strong interaction between the Fe and B atoms. The Dirac state in FeB2 system primarily arises from the Fe d orbitals and hybridized orbital from Fe-d and B-p states. The newly predicted FeB2 monolayer has excellent dynamic and thermal stabilities and is also the global minimum of 2D FeB2 system, implying its experimental feasibility. Our results are beneficial to further uncovering the mechanism of the Dirac cones and providing a feasible strategy for Dirac materials design.

  7. In situ synthesis of superconducting MgB2 fibers within a magnesium matrix

    NASA Astrophysics Data System (ADS)

    DeFouw, John D.; Dunand, David C.

    2003-07-01

    Composite wires, consisting of several hundred continuous MgB2 fibers embedded within an Mg matrix, are produced by a casting method, whereby liquid Mg is pressure infiltrated into a preform of aligned B fibers which are subsequently reacted in situ to form MgB2 fibers. Despite defects in the form of small, unreacted B islands and radial cracks from volume expansion, the MgB2 fibers exhibit superconducting properties (Tc=39 K and Jc=360 kA/cm2 at 5 K) comparable to the best results published for bulk MgB2. The fibers are cylindrical and straight, allowing high packing densities within a mechanically tough, thermally dissipating, electrically conductive Mg matrix. The process is scalable to continuous lengths of superconducting Mg/MgB2 wires.

  8. TrpB2 enzymes are O-phospho-l-serine dependent tryptophan synthases.

    PubMed

    Busch, Florian; Rajendran, Chitra; Mayans, Olga; Löffler, Patrick; Merkl, Rainer; Sterner, Reinhard

    2014-09-30

    The rapid increase of the number of sequenced genomes asks for the functional annotation of the encoded enzymes. We used a combined computational-structural approach to determine the function of the TrpB2 subgroup of the tryptophan synthase β chain/β chain-like TrpB1-TrpB2 family (IPR023026). The results showed that TrpB2 enzymes are O-phospho-l-serine dependent tryptophan synthases, whereas TrpB1 enzymes catalyze the l-serine dependent synthesis of tryptophan. We found a single residue being responsible for the different substrate specificities of TrpB1 and TrpB2 and confirmed this finding by mutagenesis studies and crystallographic analysis of a TrpB2 enzyme with bound O-phospho-l-serine.

  9. NEUTRONIC REACTOR FUEL COMPOSITION

    DOEpatents

    Thurber, W.C.

    1961-01-10

    Uranium-aluminum alloys in which boron is homogeneously dispersed by adding it as a nickel boride are described. These compositions have particular utility as fuels for neutronic reactors, boron being present as a burnable poison.

  10. NEUTRONIC REACTOR STRUCTURE

    DOEpatents

    Daniels, F.

    1961-10-24

    A reactor core, comprised of vertical stacks of hexagonal blocks of beryllium oxide having axial cylindrical apertures extending therethrough and cylindrical rods of a sintered mixture of uranium dioxide and beryllium oxide, is described. (AEC)

  11. Reactor Neutrino Spectra

    NASA Astrophysics Data System (ADS)

    Hayes, Anna C.; Vogel, Petr

    2016-10-01

    We present a review of the antineutrino spectra emitted from reactors. Knowledge of these spectra and their associated uncertainties is crucial for neutrino oscillation studies. The spectra used to date have been determined either by converting measured electron spectra to antineutrino spectra or by summing over all of the thousands of transitions that make up the spectra, using modern databases as input. The uncertainties in the subdominant corrections to β-decay plague both methods, and we provide estimates of these uncertainties. Improving on current knowledge of the antineutrino spectra from reactors will require new experiments. Such experiments would also address the so-called reactor neutrino anomaly and the possible origin of the shoulder observed in the antineutrino spectra measured in recent high-statistics reactor neutrino experiments.

  12. Packed Bed Reactor Experiment

    NASA Video Gallery

    The purpose of the Packed Bed Reactor Experiment in low gravity is to determine how a mixture of gas and liquid flows through a packed bed in reduced gravity. A packed bed consists of a metal pipe ...

  13. Ex situ MgB2 barrier behavior of monofilament in situ MgB2 wires with Glidcop® sheath material

    NASA Astrophysics Data System (ADS)

    Kario, A.; Morawski, A.; Häßler, W.; Nenkov, K.; Schubert, M.; Herrmann, M.; Ringsdorf, B.; Schlachter, S. I.; Goldacker, W.; Holzapfel, B.; Schultz, L.

    2010-11-01

    Cost-effective MgB2 wires are highly sought after to replace the widely used NbTi conductors in superconducting magnets, e.g. for magnetic resonance imaging (MRI). One method of choice for lowering conductor costs is to use a less expensive barrier and sheath material. From this point of view copper is a good candidate for the sheath, and additionally has other advantageous properties, e.g. the best electrical and thermal conductivity at operating temperature. One major disadvantage of copper is its high chemical reactivity. This material reacts fast with magnesium and forms Mg-Cu alloys, removing the starting element necessary for MgB2 formation. To prevent this reaction, a special coaxial architecture was applied using ex situ MgB2 powder as a chemical barrier between the copper sheath and the in situ MgB2 powder core. The Glidcop® (dispersed strengthened copper) sheathed MgB2 wires with an ex situ barrier have been fabricated by the conventional powder in tube (PIT) method. Besides avoiding the reaction of Mg and Cu, the barrier also contributes to the superconducting core fraction and increases the filling factor up to 50%. The Glidcop® sheathed wires with an ex situ MgB2 commercial powder used as a barrier have been successfully drawn to a diameter of 1.2 mm and then a pressure-assisted heat treatment was applied. For our case of specified in situ and ex situ powders the pressure-assisted preparation of at least 0.15 GPa was found to be important for the densification of the ex situ barrier.

  14. Mycobacterium smegmatis DinB2 misincorporates deoxyribonucleotides and ribonucleotides during templated synthesis and lesion bypass

    PubMed Central

    Ordonez, Heather; Shuman, Stewart

    2014-01-01

    Mycobacterium smegmatis DinB2 is the founder of a clade of Y-family DNA polymerase that is naturally adept at utilizing rNTPs or dNTPs as substrates. Here we investigate the fidelity and lesion bypass capacity of DinB2. We report that DinB2 is an unfaithful DNA and RNA polymerase with a distinctive signature for misincorporation of dNMPs, rNMPs and oxoguanine nucleotides during templated synthesis in vitro. DinB2 has a broader mutagenic spectrum with manganese than magnesium, though low ratios of manganese to magnesium suffice to switch DinB2 to its more mutagenic mode. DinB2 discrimination against incorrect dNTPs in magnesium is primarily at the level of substrate binding affinity, rather than kpol. DinB2 can incorporate any dNMP or rNMP opposite oxo-dG in the template strand with manganese as cofactor, with a kinetic preference for synthesis of an A:oxo-dG Hoogsteen pair. With magnesium, DinB2 is adept at synthesizing A:oxo-dG or C:oxo-dG pairs. DinB2 effectively incorporates deoxyribonucleotides, but not ribonucleotides, opposite an abasic site, with kinetic preference for dATP as the substrate. We speculate that DinB2 might contribute to mycobacterial mutagenesis, oxidative stress and quiescence, and discuss the genetic challenges to linking the polymerase biochemistry to an in vivo phenotype. PMID:25352547

  15. LytB1 and LytB2 of Mycobacterium tuberculosis Are Not Genetically Redundant

    PubMed Central

    Brown, Amanda Claire; Kokoczka, Rachel; Parish, Tanya

    2015-01-01

    Mycobacterium tuberculosis synthesises isoprenoid precursors via the MEP/DOXP pathway and at least five enzymes in the pathway (Dxs1, Dxr/IspC, IspD, IspF, and GcpE/IspG) are required for growth in vitro. We investigated the role of LytB (IspH) in M. tuberculosis; M. tuberculosis is unusual in that it has two homologs–LytB1 and LytB2. We were unable to delete the lytB2 gene unless we provided an additional copy elsewhere, demonstrating that this is the essential homolog. We expressed lytB1 from the lytB2 promoter and confirmed that this could not complement for loss of function of lytB2, despite LytB1 possessing all the previously described conserved critical residues. Interestingly the sole LytB homolog of Mycobacterium smegmatis was able to compensate for loss of LytB2 in M. tuberculosis. We tested translational fusions of LytB1 and LytB2 for functionality in M. tuberculosis, but only a fusion with 90% N-terminal LytB2 and 10% C-terminal LytB1 was functional. In order to identify the key difference between the two proteins, site directed mutagenesis was used to change LytB2 residues into their counterparts in LytB1. None of these amino acid substitutions was essential for function and all lytB2 mutant alleles were functional. In contrast, mutation of the key residues for [Fe4S4] cluster formation, as well as a catalytic residue in LytB1 did not result in functional complementation. Thus, although LytB1 and LytB2 are not genetically redundant, this is not dependent on small amino acid changes, but is likely to be a result of major overall structural differences. PMID:26309039

  16. Mutational activation of ErbB2 reveals a new protein kinase autoinhibition mechanism.

    PubMed

    Fan, Ying-Xin; Wong, Lily; Ding, Jinhui; Spiridonov, Nikolay A; Johnson, Richard C; Johnson, Gibbes R

    2008-01-18

    Autoinhibition plays a key role in the control of protein kinase activity. ErbB2 is a unique receptor-tyrosine kinase that does not bind ligand but possesses an extracellular domain poised to engage other ErbBs. Little is known about the molecular mechanism for ErbB2 catalytic regulation. Here we show that ErbB2 kinase is strongly autoinhibited, and a loop connecting the alphaC helix and beta4 sheet within the kinase domain plays a major role in the control of kinase activity. Mutations of two Gly residues at positions 776 and 778 in this loop dramatically increase ErbB2 catalytic activity. Kinetic analysis demonstrates that mutational activation is due to approximately 10- and approximately 7-fold increases in ATP binding affinity and turnover number, respectively. Expression of the activated ErbB2 mutants in cells resulted in elevated ligand-independent ErbB2 autophosphorylation, ErbB3 phosphorylation, and stimulation of mitogen-activated protein kinase. Molecular modeling suggests that the ErbB2 kinase domain is stabilized in an inactive state via a hydrophobic interaction between the alphaC-beta4 and activation loops. Importantly, many ErbB2 human cancer mutations have been identified in the alphaC-beta4 loop, including the activating G776S mutation studied here. Our findings reveal a new kinase regulatory mechanism in which the alphaC-beta4 loop functions as an intramolecular switch that controls ErbB2 activity and suggests that loss of alphaC-beta4 loop-mediated autoinhibition is involved in oncogenic activation of ErbB2.

  17. Molten metal reactors

    DOEpatents

    Bingham, Dennis N; Klingler, Kerry M; Turner, Terry D; Wilding, Bruce M

    2013-11-05

    A molten metal reactor for converting a carbon material and steam into a gas comprising hydrogen, carbon monoxide, and carbon dioxide is disclosed. The reactor includes an interior crucible having a portion contained within an exterior crucible. The interior crucible includes an inlet and an outlet; the outlet leads to the exterior crucible and may comprise a diffuser. The exterior crucible may contain a molten alkaline metal compound. Contained between the exterior crucible and the interior crucible is at least one baffle.

  18. Compact power reactor

    DOEpatents

    Wetch, Joseph R.; Dieckamp, Herman M.; Wilson, Lewis A.

    1978-01-01

    There is disclosed a small compact nuclear reactor operating in the epithermal neutron energy range for supplying power at remote locations, as for a satellite. The core contains fuel moderator elements of Zr hydride with 7 w/o of 93% enriched uranium alloy. The core has a radial beryllium reflector and is cooled by liquid metal coolant such as NaK. The reactor is controlled and shut down by moving portions of the reflector.

  19. Future reactor experiments

    SciTech Connect

    Wen, Liangjian

    2015-07-15

    The non-zero neutrino mixing angle θ{sub 13} has been discovered and precisely measured by the current generation short-baseline reactor neutrino experiments. It opens the gate of measuring the leptonic CP-violating phase and enables the neutrino mass ordering. The JUNO and RENO-50 proposals aim at resolving the neutrino mass ordering using reactors. The experiment design, physics sensitivity, technical challenges as well as the progresses of those two proposed experiments are reviewed in this paper.

  20. K-Reactor readiness

    SciTech Connect

    Rice, P.D.

    1991-12-04

    This document describes some of the more significant accomplishments in the reactor restart program and details the magnitude and extent of the work completed to bring K-Reactor to a state of restart readiness. The discussion of restart achievements is organized into the three major categories of personnel, programs, and plant. Also presented is information on the scope and extent of internal and external oversight of the efforts, as well as some details on the startup plan.

  1. Effects of Phase Change and Oxygen Permeability in Oxide Scales on Oxidation Kinetics of ZrB2 and HfB2 (POSTPRINT)

    DTIC Science & Technology

    2009-11-01

    Materials,’’ SAMPE Quar- terly, 2 [3] 1–15 (1971). 10J. B. Berkowitz-Mattuck, ‘‘High-Temperature Oxidation III : Zirconium and Hafnium Diborides ,’’ J...1959). 30L. Kaufman, E. V. Clougherty, and J. B. Berkowitz-Mattuck, ‘‘Oxidation Characteristics of Hafnium and Zirconium Diboride ,’’ Trans. of Met. Soc...interface i B2O3(l)–B2O3(g) interface I. Introduction DIBORIDES of Zr and Hf are now well recognized as the mostpromising refractory materials that are

  2. The 3A2, 1A2, 3B2, and 1B2 electronic states of CH2: Small bond angle states

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Yukio; Schaefer, Henry F., III

    1997-02-01

    Molecular structures with very small bond angles are a curiosity in chemistry. The two triplet (3A2 and 3B2) and two singlet (1A2 and 1B2) excited states of CH2 have been investigated systematically using ab initio electronic structure theory. For these four states total energies and physical properties including geometries, dipole moments, harmonic vibrational frequencies, and associated infrared intensities were determined with the single and double excitation configuration interaction (CISD) method using four different basis sets. It is confirmed in this study that the four states of CH2 all have bent structures with longer CH bond lengths and smaller bond angles than the four lower-lying (X˜, ã, b˜, and c˜) states of CH2. At the CISD optimized geometries single point energies were determined with complete active space self-consistent-field (CASSCF) and CASSCF second-order configuration interaction (SOCI) levels of theory. For the triplet excited states single point energies were also determined employing coupled cluster with single and double excitations (CCSD) and CCSD with perturbative triple excitations methods. At the CISD level with the largest basis set, the triple zeta plus triple polarizations with two sets of higher angular momentum and two sets of diffuse functions basis set [TZ3P(2 f,2d)+2diff], the bond angles were predicted to be 40.6° (3A2), 46.1° (1A2), 76.3° (3B2), and 81.3° (1B2), while the dipole moments were determined to be 2.35 (3A2), 2.26 (1A2), 1.69 (3B2), and 1.60 debye (1B2), respectively. With the most accurate method in this study, the CASSCF-SOCI level with the TZ3P(2 f,2d)+2diff basis set, the energy separations (Te value) between the ground state (X˜ 3B1) and the four excited states were predicted to be 73.7 kcal/mol (3.20 eV, 25 800 cm-1) for the 3A2 state, 96.8 kcal/mol (4.20 eV, 33 800 cm-1) for the 1A2 state, 151.0 kcal/mol (6.55 eV, 52 800 cm-1) for the 3B2 state, and 182.5 kcal/mol (7.91 eV, 63 800 cm-1) for the 1B2

  3. NEUTRONIC REACTOR CONSTRUCTION AND OPERATION

    DOEpatents

    West, J.M.; Weills, J.T.

    1960-03-15

    A method is given for operating a nuclear reactor having a negative coefficient of reactivity to compensate for the change in reactor reactivity due to the burn-up of the xenon peak following start-up of the reactor. When it is desired to start up the reactor within less than 72 hours after shutdown, the temperature of the reactor is lowered prior to start-up, and then gradually raised after start-up.

  4. F Reactor Inspection

    SciTech Connect

    Grindstaff, Keith; Hathaway, Boyd; Wilson, Mike

    2014-10-29

    Workers from Mission Support Alliance, LLC., removed the welds around the steel door of the F Reactor before stepping inside the reactor to complete its periodic inspection. This is the first time the Department of Energy (DOE) has had the reactor open since 2008. The F Reactor is one of nine reactors along the Columbia River at the Department's Hanford Site in southeastern Washington State, where environmental cleanup has been ongoing since 1989. As part of the Tri-Party Agreement, the Department completes surveillance and maintenance activities of cocooned reactors periodically to evaluate the structural integrity of the safe storage enclosure and to ensure confinement of any remaining hazardous materials. "This entry marks a transition of sorts because the Hanford Long-Term Stewardship Program, for the first time, was responsible for conducting the entry and surveillance and maintenance activities," said Keith Grindstaff, Energy Department Long-Term Stewardship Program Manager. "As the River Corridor cleanup work is completed and transitioned to long-term stewardship, our program will manage any on-going requirements."

  5. F Reactor Inspection

    ScienceCinema

    Grindstaff, Keith; Hathaway, Boyd; Wilson, Mike

    2016-07-12

    Workers from Mission Support Alliance, LLC., removed the welds around the steel door of the F Reactor before stepping inside the reactor to complete its periodic inspection. This is the first time the Department of Energy (DOE) has had the reactor open since 2008. The F Reactor is one of nine reactors along the Columbia River at the Department's Hanford Site in southeastern Washington State, where environmental cleanup has been ongoing since 1989. As part of the Tri-Party Agreement, the Department completes surveillance and maintenance activities of cocooned reactors periodically to evaluate the structural integrity of the safe storage enclosure and to ensure confinement of any remaining hazardous materials. "This entry marks a transition of sorts because the Hanford Long-Term Stewardship Program, for the first time, was responsible for conducting the entry and surveillance and maintenance activities," said Keith Grindstaff, Energy Department Long-Term Stewardship Program Manager. "As the River Corridor cleanup work is completed and transitioned to long-term stewardship, our program will manage any on-going requirements."

  6. Moon base reactor system

    NASA Technical Reports Server (NTRS)

    Chavez, H.; Flores, J.; Nguyen, M.; Carsen, K.

    1989-01-01

    The objective of our reactor design is to supply a lunar-based research facility with 20 MW(e). The fundamental layout of this lunar-based system includes the reactor, power conversion devices, and a radiator. The additional aim of this reactor is a longevity of 12 to 15 years. The reactor is a liquid metal fast breeder that has a breeding ratio very close to 1.0. The geometry of the core is cylindrical. The metallic fuel rods are of beryllium oxide enriched with varying degrees of uranium, with a beryllium core reflector. The liquid metal coolant chosen was natural lithium. After the liquid metal coolant leaves the reactor, it goes directly into the power conversion devices. The power conversion devices are Stirling engines. The heated coolant acts as a hot reservoir to the device. It then enters the radiator to be cooled and reenters the Stirling engine acting as a cold reservoir. The engines' operating fluid is helium, a highly conductive gas. These Stirling engines are hermetically sealed. Although natural lithium produces a lower breeding ratio, it does have a larger temperature range than sodium. It is also corrosive to steel. This is why the container material must be carefully chosen. One option is to use an expensive alloy of cerbium and zirconium. The radiator must be made of a highly conductive material whose melting point temperature is not exceeded in the reactor and whose structural strength can withstand meteor showers.

  7. Reactor Safety Research Programs

    SciTech Connect

    Dotson, CW

    1980-08-01

    This document summarizes the work performed by Pacific Northwest laboratory from October 1 through December 31, 1979, for the Division of Reactor Safety Research within the Nuclear Regulatory Commission. Evaluation of nondestructive examination (NDE) techniques and instrumentation are reported; areas of investigation include demonstrating the feasibilty of determining structural graphite strength, evaluating the feasibilty of detecting and analyzing flaw growth in reactor pressure boundary systems, examining NDE reliability and probabilistic fracture mechanics, and assessing the remaining integrity of pressurized water reactor steam generator tubes where service-induced degradation has been indicated. Test assemblies and analytical support are being provided for experimental programs at other facilities. These programs include the loss-of-coolant accident simulation tests at the NRU reactor, Chalk River, Canada; the fuel rod deformation and post-accident coolability tests for the ESSOR Test Reactor Program, lspra, Italy; the blowdown and reflood tests in the test facility at Cadarache, France; the instrumented fuel assembly irradiation program at Halden, Norway; and the experimental programs at the Power Burst Facility, Idaho National Engineering Laboratory. These programs will provide data for computer modeling of reactor system and fuel performance during various abnormal operating conditions.

  8. Signatures of spin-glass behaviour in PrIr2B2 and heavy fermion behaviour in PrIr2B2C.

    PubMed

    Anupam; Anand, V K; Hossain, Z; Adroja, D T; Geibel, C

    2011-09-21

    The magnetic and transport properties of PrIr(2)B(2) and PrIr(2)B(2)C have been investigated by dc and ac magnetic susceptibility, specific heat, electrical resistivity and magnetoresistance measurements. PrIr(2)B(2) forms in CaRh(2)B(2)-type orthorhombic crystal structure (space group Fddd). At low fields the dc magnetic susceptibility of PrIr(2)B(2) exhibits a sharp anomaly near 46 K which is followed by an abrupt increase below 10 K with a peak at 6 K, and split-up in ZFC and FC data below 46 K. In contrast, the specific heat exhibits only a broad Schottky type hump near 9 K which indicates that there is no long range magnetic order in this compound. The thermo-remanent magnetization is found to decay very slowly with a mean relaxation time τ = 3917 s. An ac magnetic susceptibility measurement also observes two sharp anomalies; the peak positions strongly depend on the frequency and shift towards high temperature with an increase in frequency, obeying the Vogel-Fulcher law as expected for a canonical spin-glass system. The two spin-glass transitions occur at freezing temperatures T(f1) = 36 K and T(f2) = 3.5 K with shifts in the freezing temperatures per decade of frequency δT(f1) = 0.044 and δT(f2) = 0.09. An analysis of the frequency dependence of the transition temperature with critical slowing down, τ(max)/τ(0) = [(T(f)-T(SG))/T(SG)](-zν), gives τ(0) = 10(-7) s and exponent zν = 8, and the Vogel-Fulcher law gives an activation energy of 84 K for T(f1) and 27.5 K for T(f2). While zν = 8 is typical for spin-glass system, the characteristic relaxation time τ(0) = 10(-7) s is very large and comparable to that of superspin-glass systems. An addition of C in PrIr(2)B(2) leads to PrIr(2)B(2)C which forms in LuNi(2)B(2)C-type tetragonal structure (space group I4/mmm) and remains paramagnetic down to 2 K. The specific heat data show a broad Schottky type anomaly, which could be fairly reproduced with CEF analysis which suggests that the ground state is a

  9. Adoption of the B2SAFE EUDAT replication service by the EPOS community

    NASA Astrophysics Data System (ADS)

    Cacciari, Claudio; Fares, Massimo; Fiameni, Giuseppe; Michelini, Alberto; Danecek, Peter; Wittenburg, Peter

    2014-05-01

    B2SAFE is the EUDAT service for moving and replicating data between sites and storage systems for different purposes. The goal of B2SAFE is to keep the data from a repository safe by replicating it across different geographical and administrative zones according to a set of well-defined policies. It is also a way to store large volumes of data permanently at those sites which are providing powerful on-demand data analysis facilities. In particular, B2SAFE operates on the domain of registered data where data objects are referable via persistent identifiers (PIDs). B2SAFE is more than just copying data because the PIDs must be carefully managed when data objects are moved or replicated. The EUDAT B2SAFE Service offers functionality to replicate datasets across different data centres in a safe and efficient way while maintaining all information required to easily find and query information about the replica locations. The information about the replica locations and other important information is stored in PID records, each managed in separate administrative domains. The B2SAFE Service is implemented as an iRODS module providing a set of iRODS rules or policies to interface with the EPIC handle API and uses the iRODS middleware to replicate datasets from a source data (or community) centre to a destination data centre. The definition of the dataset(s) to replicate is flexible and up to the communities using the B2SAFE service. While the B2SAFE is internally using the EPIC handle API, communities have the choice to use any PID system they prefer to assign PIDs to their digital objects. A reference to one or more EUDAT B2SAFE PIDs is returned by the B2SAFE service when a dataset is replicated. The presentation will introduce the problem space of B2SAFE, presents the achievements that have been made during the last year for enabling communities to make use of the B2SAFE service, demonstrates a EPOS use cases, outlines the commonalities and differences between the policies

  10. Low-temperature synthesis of MgB2 via powder metallurgy processing

    NASA Astrophysics Data System (ADS)

    Birol, Yucel

    2016-12-01

    Ball-milled Mg/B2O3 powder blends reveal interpenetrating layers of deformed magnesium and boron oxide grains that are increasingly refined with increasing milling time. Boron oxide is reduced by Mg and MgO thus formed reacts with the remaining B2O3 to produce Mg3(BO3)2 during ball milling for 30 min. Both B2O3 and Mg3(BO3)2 react with Mg to produce MgB2 upon further ball milling. An annealing treatment can be employed when ball milling is performed for less than 1 h as thermal exposure of the ball-milled Mg/B2O3 powder blends also leads to the formation of MgB2. The above reactions take place between 500 and 700 °C when the Mg/B2O3 powder blend is ball milled for 30 min, and between 450 and 550 °C, after ball milling for 1 h. This is a very attractive route owing to processing temperatures where the volatility of Mg is no longer a problem.

  11. Anderson lattice in the intermediate valence compound Ce3Ni2B2N3-δ

    NASA Astrophysics Data System (ADS)

    Ali, Tahir; Bauer, Ernst; Hilscher, Gerfried; Michor, Herwig

    2011-03-01

    We have studied magnetic, thermodynamic, and transport properties of Ce3Ni2B2N3-δ and its solid solution with the Tc≃13 K superconductor La3Ni2B2N3-δ. The solid solution (La,Ce)3Ni2B2N3-δ reveals a rapid reduction of Tc by increasing the Ce content with a complete suppression of superconductivity at the composition La2.85Ce0.15Ni2B2N3-δ. The low-temperature properties characterize Ce3Ni2B2N3-δ as an intermediate valence system with a moderately enhanced Sommerfeld value γ≃54 mJ/mol K2 and a susceptibility χ0≃1.6×10-3 emu/mol, increased by about one order of magnitude as compared to the respective value χ0≃0.2×10-3 emu/mol of superconducting La3Ni2B2N3-δ (γ=26 mJ/mol K2) which serves as reference with a nonmagnetic rare earth ion. The electrical resistivity and thermoelectric power of Ce3Ni2B2N3-δ are analyzed in terms of the degenerate Anderson lattice model revealing a characteristic Kondo temperature TKALM~1100 K.

  12. ErbB2 resembles an autoinhibited invertebrate epidermal growth factor receptor

    SciTech Connect

    Alvarado, Diego; Klein, Daryl E.; Lemmon, Mark A.

    2009-09-25

    The orphan receptor tyrosine kinase ErbB2 (also known as HER2 or Neu) transforms cells when overexpressed, and it is an important therapeutic target in human cancer. Structural studies have suggested that the oncogenic (and ligand-independent) signalling properties of ErbB2 result from the absence of a key intramolecular 'tether' in the extracellular region that autoinhibits other human ErbB receptors, including the epidermal growth factor (EGF) receptor. Although ErbB2 is unique among the four human ErbB receptors, here we show that it is the closest structural relative of the single EGF receptor family member in Drosophila melanogaster (dEGFR). Genetic and biochemical data show that dEGFR is tightly regulated by growth factor ligands, yet a crystal structure shows that it, too, lacks the intramolecular tether seen in human EGFR, ErbB3 and ErbB4. Instead, a distinct set of autoinhibitory interdomain interactions hold unliganded dEGFR in an inactive state. All of these interactions are maintained (and even extended) in ErbB2, arguing against the suggestion that ErbB2 lacks autoinhibition. We therefore suggest that normal and pathogenic ErbB2 signalling may be regulated by ligands in the same way as dEGFR. Our findings have important implications for ErbB2 regulation in human cancer, and for developing therapeutic approaches that target novel aspects of this orphan receptor.

  13. EphrinB2 regulates the emergence of a hemogenic endothelium from the aorta

    PubMed Central

    Chen, Inn-Inn; Caprioli, Arianna; Ohnuki, Hidetaka; Kwak, Hyeongil; Porcher, Catherine; Tosato, Giovanna

    2016-01-01

    Adult-type intraembryonic hematopoiesis arises from specialized endothelial cells of the dorsal aorta (DA). Despite the critical importance of this specialized endothelium for establishment of hematopoietic stem cells and adult hematopoietic lineages, the mechanisms regulating its emergence are incompletely understood. We show that EphrinB2, a principal regulator of endothelial cell function, controls the development of endothelium producing adult-type hematopoiesis. The absence of EphrinB2 impairs DA-derived hematopoiesis. Transmembrane EphrinB2 and its EphB4 receptor interact in the emerging DA, which transiently harbors EphrinB2+ and EphB4+ endothelial cells, thereby providing an opportunity for bi-directional cell-to-cell signaling to control the emergence of the hemogenic endothelium. Embryonic Stem (ES) cell-derived EphrinB2+ cells are enriched with hemogenic endothelial precursors. EphrinB2 silencing impairs ES generation of hematopoietic cells but not generation of endothelial cells. The identification of EphrinB2 as an essential regulator of adult hematopoiesis provides important insight in the regulation of early hematopoietic commitment. PMID:27250641

  14. Differential Distribution of Bradykinin B(2) Receptors in the Rat and Human Cardiovascular System.

    PubMed

    Figueroa, Carlos D.; Marchant, Alejandra; Novoa, Ulises; Förstermann, Ulrich; Jarnagin, Kurt; Schölkens, Bernward; Müller-Esterl, Werner

    2001-01-01

    -Bradykinin, a major vasodilator peptide, plays an important role in the local regulation of blood pressure, blood flow, and vascular permeability; however, the cellular distribution of the major bradykinin B(2) receptor in the cardiovascular system is not precisely known. Immunoblot analysis with an anti-peptide antibody to the bradykinin B(2) receptor or chemical cross-linkage with [(125)I]Tyr(0)-bradykinin revealed a band of 69+/-3 kDa at varying intensity in the homogenates of the endothelium and tunica media of the rat aorta and endocardium. Immunostaining showed that the B(2) receptor is abundant in the endothelial linings of the aorta, other elastic arteries, muscular arteries, capillaries, venules, and large veins, where it localizes preferentially to the luminal face of the endothelial cells. In marked contrast, small arterioles (ie, the principal blood-pressure regulating vessels) of the mesenterium, heart, urinary bladder, brain, salivary gland, and kidney had a different staining pattern in which B(2) receptor was prominent in the perivascular smooth muscle cells of the tunica media. A similar distribution pattern was found in mouse as well as in human tissues, indicating that the particular distribution pattern of the B(2) receptor in arterioles is not a species-specific phenomenon. During development, the distribution of B(2) receptor in the heart changes; for example, in the heart of newborn rats, the B(2) receptor was abundant in the myocardium, whereas in the adult heart, the receptor was present in the endocardium of atria, atrioventricular valves, and ventricles but not in the myocardium. Thus, B(2) receptors are localized differentially in different parts of the cardiovascular system: the arterioles have smooth muscle-localized B(2) receptors, and large elastic vessels have endothelium-localized receptors.

  15. Neuropsin cleaves EphB2 in the amygdala to control anxiety

    PubMed Central

    Attwood, Benjamin; Bourgognon, Julie-Myrtille; Patel, Satyam; Mucha, Mariusz; Schiavon, Emanuele; Skrzypiec, Anna E.; Young, Kenneth W.; Shiosaka, Sadao; Korostynski, Michał; Piechota, Marcin; Przewłocki, Ryszard; Pawlak, Robert

    2011-01-01

    Summary A minority of individuals experiencing traumatic events develop anxiety disorders. The reason for the lack of correspondence between the prevalence of exposure to psychological trauma and the development of anxiety is unknown. Extracellular proteolysis contributes to fear-associated responses by facilitating neuronal plasticity at the neuron-matrix interface1-4. Here we show that the serine protease neuropsin is critical for stress-related plasticity in the amygdala by regulating the dynamics of EphB2/NMDA receptor interaction, the expression of Fkbp5 and anxiety-like behaviour. Stress results in neuropsin-dependent cleavage of EphB2 in the amygdala causing dissociation of EphB2 from the NR1-subunit of NMDA receptor and promoting membrane turnover of EphB2 receptors. Dynamic EphB2/NR1 interaction enhances NMDA receptor current, induces the Fkbp5 gene expression and enhances behavioural signatures of anxiety. Upon stress, neuropsin-deficient mice do not show EphB2 cleavage and its dissociation from NR1 resulting in a static EphB2/NR1 interaction, attenuated induction of the Fkbp5 gene and low anxiety. The behavioural response to stress can be restored by intra-amygdala injection of neuropsin into neuropsin-deficient mice and disrupted by the injection of either anti-EphB2 antibodies or silencing the Fkbp5 gene in the amygdala of wild-type animals. Our findings establish a novel neuronal pathway linking stress-induced proteolysis of EphB2 in the amygdala to anxiety. PMID:21508957

  16. Nociceptor-expressed ephrin-B2 regulates inflammatory and neuropathic pain

    PubMed Central

    2010-01-01

    Background EphB receptors and their ephrin-B ligands play an important role in nervous system development, as well as synapse formation and plasticity in the adult brain. Recent studies show that intrathecal treatment with EphB-receptor activator ephrinB2-Fc induced thermal hyperalgesia and mechanical allodynia in rat, indicating that ephrin-B2 in small dorsal root ganglia (DRG) neurons and EphB receptors in the spinal cord modulate pain processing. To examine the role of ephrin-B2 in peripheral pain pathways, we deleted ephrin-B2 in Nav1.8+ nociceptive sensory neurons with the Cre-loxP system. Sensory neuron numbers and terminals were examined using neuronal makers. Pain behavior in acute, inflammatory and neuropathic pain models was assessed in the ephrin-B2 conditional knockout (CKO) mice. We also investigated the c-Fos expression and NMDA receptor NR2B phosphorylation in ephrin-B2 CKO mice and littermate controls. Results The ephrin-B2 CKO mice were healthy with no sensory neuron loss. However, pain-related behavior was substantially altered. Although acute pain behavior and motor co-ordination were normal, inflammatory pain was attenuated in ephrin-B2 mutant mice. Complete Freund's adjuvant (CFA)-induced mechanical hyperalgesia was halved. Formalin-induced pain behavior was attenuated in the second phase, and this correlated with diminished tyrosine phosphorylation of N-methyl-D-aspartic acid (NMDA) receptor subunit NR2B in the dorsal horn. Thermal hyperalgesia and mechanical allodynia were significantly reduced in the Seltzer model of neuropathic pain. Conclusions Presynaptic ephrin-B2 expression thus plays an important role in regulating inflammatory pain through the regulation of synaptic plasticity in the dorsal horn and is also involved in the pathogenesis of some types of neuropathic pain. PMID:21059214

  17. Molecular cloning and characterization of SoxB2 gene from Zhikong scallop Chlamys farreri

    NASA Astrophysics Data System (ADS)

    He, Yan; Bao, Zhenmin; Guo, Huihui; Zhang, Yueyue; Zhang, Lingling; Wang, Shi; Hu, Jingjie; Hu, Xiaoli

    2013-11-01

    The Sox proteins play critical roles during the development of animals, including sex determination and central nervous system development. In this study, the SoxB2 gene was cloned from a mollusk, the Zhikong scallop ( Chlamys farreri), and characterized with respect to phylogeny and tissue distribution. The full-length cDNA and genomic DNA sequences of C. farreri SoxB2 ( Cf SoxB2) were obtained by rapid amplification of cDNA ends and genome walking, respectively, using a partial cDNA fragment from the highly conserved DNA-binding domain, i.e., the High Mobility Group (HMG) box. The full-length cDNA sequence of Cf SoxB2 was 2 048 bp and encoded 268 amino acids protein. The genomic sequence was 5 551 bp in length with only one exon. Several conserved elements, such as the TATA-box, GC-box, CAAT-box, GATA-box, and Sox/sry-sex/testis-determining and related HMG box factors, were found in the promoter region. Furthermore, real-time quantitative reverse transcription PCR assays were carried out to assess the mRNA expression of Cf SoxB 2 in different tissues. SoxB2 was highly expressed in the mantle, moderately in the digestive gland and gill, and weakly expressed in the gonad, kidney and adductor muscle. In male and female gonads at different developmental stages of reproduction, the expression levels of Cf SoxB2 were similar. Considering the specific expression and roles of SoxB 2 in other animals, in particular vertebrates, and the fact that there are many pallial nerves in the mantle, cerebral ganglia in the digestive gland and gill nerves in gill, we propose a possible essential role in nervous tissue function for Sox B 2 in C. farreri.

  18. Primary Role for Kinin B1 and B2 Receptors in Glioma Proliferation.

    PubMed

    Nicoletti, Natália Fontana; Sénécal, Jacques; da Silva, Vinicius Duval; Roxo, Marcelo R; Ferreira, Nelson Pires; de Morais, Rafael Leite T; Pesquero, João Bosco; Campos, Maria Martha; Couture, Réjean; Morrone, Fernanda Bueno

    2016-11-16

    This study investigated the role of kinins and their receptors in malignant brain tumors. As a first approach, GL-261 glioma cells were injected (2 × 10(5) cells in 2 μl/2 min) into the right striatum of adult C57/BL6 wild-type, kinin B1 and B2 receptor knockout (KOB1R and KOB2R) and B1 and B2 receptor double knockout mice (KOB1B2R). The animals received the selective B1R (SSR240612) and/or B2R (HOE-140) antagonists by intracerebroventricular (i.c.v.) route at 5, 10, and 15 days. The tumor size quantification, mitotic index, western blot analysis, quantitative autoradiography, immunofluorescence, and confocal microscopy were carried out in brain tumor samples, 20 days after tumor induction. Our results revealed an uncontrolled tumor growing in KOB1R or SSR240612-treated mice, which was blunted by B2R blockade with HOE-140, suggesting a crosstalk between B1R and B2R in tumor growing. Combined treatment with B1R and B2R antagonists normalized the upregulation of tumor B1R and decreased the tumor size and the mitotic index, as was seen in double KOB1B2R. The B1R was detected on astrocytes in the tumor, indicating a close relationship between this receptor and astroglial cells. Noteworthy, an immunohistochemistry analysis of tumor samples from 16 patients with glioma diagnosis revealed a marked B1R immunopositivity in low-grade gliomas or in older glioblastoma individuals. Furthermore, the clinical data revealed a significantly higher immunopositivity for B1R, when compared to a lower B2R immunolabeling. Taken together, our results show that blocking simultaneously both kinin receptors or alternatively stimulating B1R may be of therapeutic value in the treatment of brain glioblastoma growth and malignancy.

  19. Reactor Safety Planning for Prometheus Project, for Naval Reactors Information

    SciTech Connect

    P. Delmolino

    2005-05-06

    The purpose of this letter is to submit to Naval Reactors the initial plan for the Prometheus project Reactor Safety work. The Prometheus project is currently developing plans for cold physics experiments and reactor prototype tests. These tests and facilities may require safety analysis and siting support. In addition to the ground facilities, the flight reactor units will require unique analyses to evaluate the risk to the public from normal operations and credible accident conditions. This letter outlines major safety documents that will be submitted with estimated deliverable dates. Included in this planning is the reactor servicing documentation and shipping analysis that will be submitted to Naval Reactors.

  20. REACTOR GROUT THERMAL PROPERTIES

    SciTech Connect

    Steimke, J.; Qureshi, Z.; Restivo, M.; Guerrero, H.

    2011-01-28

    Savannah River Site has five dormant nuclear production reactors. Long term disposition will require filling some reactor buildings with grout up to ground level. Portland cement based grout will be used to fill the buildings with the exception of some reactor tanks. Some reactor tanks contain significant quantities of aluminum which could react with Portland cement based grout to form hydrogen. Hydrogen production is a safety concern and gas generation could also compromise the structural integrity of the grout pour. Therefore, it was necessary to develop a non-Portland cement grout to fill reactors that contain significant quantities of aluminum. Grouts generate heat when they set, so the potential exists for large temperature increases in a large pour, which could compromise the integrity of the pour. The primary purpose of the testing reported here was to measure heat of hydration, specific heat, thermal conductivity and density of various reactor grouts under consideration so that these properties could be used to model transient heat transfer for different pouring strategies. A secondary purpose was to make qualitative judgments of grout pourability and hardened strength. Some reactor grout formulations were unacceptable because they generated too much heat, or started setting too fast, or required too long to harden or were too weak. The formulation called 102H had the best combination of characteristics. It is a Calcium Alumino-Sulfate grout that contains Ciment Fondu (calcium aluminate cement), Plaster of Paris (calcium sulfate hemihydrate), sand, Class F fly ash, boric acid and small quantities of additives. This composition afforded about ten hours of working time. Heat release began at 12 hours and was complete by 24 hours. The adiabatic temperature rise was 54 C which was within specification. The final product was hard and displayed no visible segregation. The density and maximum particle size were within specification.

  1. Phase transitions in a MgB2 granular BCS superconductor in weak magnetic fields

    NASA Astrophysics Data System (ADS)

    Derevyanko, V. V.; Sungurov, M. S.; Sukhareva, T. V.; Finkel', V. A.; Shakhov, Yu. N.

    2017-02-01

    The character of temperature dependences of the electric conductivity of MgB2 granular BCS superconductors at temperatures of 35-45 K in external magnetic fields H ext of up to 2 kOe is studied. An increase in the superconducting transition width Δ T c with an increase in Hext is found. The presence of a system of weak links in MgB2-based granular superconductors is established. On the basis of experimental data, MgB2 granular superconductor is assigned to two-level superconducting systems and the H-T phase diagram is constructed.

  2. Procyanidin dimer B2-mediated IRAK-M induction negatively regulates TLR4 signaling in macrophages

    SciTech Connect

    Sung, Nak-Yun; Yang, Mi-So; Song, Du-Sub; Kim, Jae-Kyung; Park, Jong-Heum; Song, Beom-Seok; Park, Sang-Hyun; Lee, Ju-Woon; Park, Hyun-Jin; Kim, Jae-Hun; Byun, Eui-Baek; Byun, Eui-Hong

    2013-08-16

    Highlights: •Pro B2 elevated the expression of IRAK-M, a negative regulator of TLR signaling. •LPS-induced expression of cell surface molecules was inhibited by Pro B2. •LPS-induced production of pro-inflammatory cytokines was inhibited by Pro B2. •Pro B2 inhibited LPS-induced activation of MAPKs and NF-κB through IRAK-M. •Pro B2 inactivated naïve T cells by inhibiting LPS-induced cytokines via IRAK-M. -- Abstract: Polyphenolic compounds have been found to possess a wide range of physiological activities that may contribute to their beneficial effects against inflammation-related diseases; however, the molecular mechanisms underlying this anti-inflammatory activity are not completely characterized, and many features remain to be elucidated. In this study, we investigated the molecular basis for the down-regulation of toll-like receptor 4 (TLR4) signal transduction by procyanidin dimer B2 (Pro B2) in macrophages. Pro B2 markedly elevated the expression of the interleukin (IL)-1 receptor-associated kinase (IRAK)-M protein, a negative regulator of TLR signaling. Lipopolysaccharide (LPS)-induced expression of cell surface molecules (CD80, CD86, and MHC class I/II) and production of pro-inflammatory cytokines (tumor necrosis factor-α, IL-1β, IL-6, and IL-12p70) were inhibited by Pro B2, and this action was prevented by IRAK-M silencing. In addition, Pro B2-treated macrophages inhibited LPS-induced activation of mitogen-activated protein kinases such as extracellular signal-regulated kinase 1/2, p38, and c-Jun N-terminal kinase and the translocation of nuclear factor κB and p65 through IRAK-M. We also found that Pro B2-treated macrophages inactivated naïve T cells by inhibiting LPS-induced interferon-γ and IL-2 secretion through IRAK-M. These novel findings provide new insights into the understanding of negative regulatory mechanisms of the TLR4 signaling pathway and the immune-pharmacological role of Pro B2 in the immune response against the development

  3. Determination of Burgers vectors in close-packed metals using g.b = 2 contrast.

    NASA Technical Reports Server (NTRS)

    Kestenbach, H.-J.; Hren, J. J.

    1972-01-01

    Reexamination of dislocation images giving double contrast in the electron microscope for g.b = 2 as a possible means for Burgers vector determinations. In fcc foils which have been cut parallel to an active slip plane, the g.b = 2 criterion provides a quick positive Burgers vector analysis which can be carried out during observation. The method is also applicable to basal dislocations in hcp. A comparison between calculated two-beam profiles and experimental images in aluminum is discussed, and several commonly observed characteristics of g.b = 2 contrast are described.

  4. Role of ErbB2 in Corneal Epithelial Wound Healing

    PubMed Central

    Xu, Ke-Ping; Riggs, April; Ding, Yu; Yu, Fu-Shin X.

    2009-01-01

    Purpose Human corneal epithelial cells (HCECs) were functionally depleted of erbB2 to elucidate its role in epidermal growth factor (EGF) receptor (EGFR) activation-dependent cell migration. Methods The retrovirus pBabe-5R, which encodes an erbB2 single-chain antibody with an endoplasmic reticulum (ER)–targeting sequence, and control pBabe-puro were used to infect THCE cells (an SV40-immortalized HCEC line). Several cell lines expressing 5R were selected along with a pBabe-puro control line. The depletion of erbB2 was verified by cell surface biotinylation of proteins, followed by streptavidin precipitation and subsequent detection of erbB2 by immunoblot analysis. Activation of erbBs was analyzed by immunoprecipitation using the phosphotyrosine antibody pY20, followed by Western blot analysis with erbB1 or erbB2 antibodies. Phosphorylation of extracellular signal-regulated kinase (ERK) and phosphatidylinositol 3′-kinase (PI3K) was analyzed by Western blot with antibodies specific to phosphorylated proteins. Effects of erbB2 depletion on heparin-binding EGF-like growth factor (HB-EGF)–induced cell migration were determined by Boyden chamber migration assay and by scratch wound assay. Results Wounding induced erbB2 tyrosine phosphorylation. Expression of 5R encoding an erbB2 single-chain antibody with an endoplasmic reticulum–targeting sequence depleted the cell surface expression of erbB2 in HCECs. Wounding resulted in a rapid increase in the phosphorylation of erbB1 in both 5R-expressing and control cells, whereas wound-induced erbB2 phosphorylation in 5R-expressing cells was not detectable. Depletion of functional erbB2 attenuated the healing of scratch wounds in the presence of HB-EGF and impaired both chemotactic migration stimulated by HB-EGF and haptotactic migration toward a fibronectin-collagen I (3:1; FNC) coating mix. Expression of 5R affected both the intensity and the duration of wound-induced, EGFR-elicited ERK and PI3K activation. Inhibition of

  5. FASN, ErbB2-mediated glycolysis is required for breast cancer cell migration.

    PubMed

    Zhou, Lan; Jiang, Sufang; Fu, Qiang; Smith, Kelly; Tu, Kailing; Li, Hua; Zhao, Yuhua

    2016-05-01

    Both fatty acid synthase (FASN) and ErbB2 have been shown to promote breast cancer cell migration. However, the underlying molecular mechanism remains poorly understood and there is no reported evidence that directly links glycolysis to breast cancer cell migration. In this study, we investigated the role of FASN, ErbB2-mediated glycolysis in breast cancer cell migration. First, we compared lactate dehydrogenase A (LDHA) protein levels, glycolysis and cell migration between FASN, ErbB2-overexpressing SK-BR-3 cells and FASN, ErbB2-low-expressing MCF7 cells. Then, SK-BR-3 cells were treated with cerulenin (Cer), an inhibitor of FASN, and ErbB2, LDHA protein levels, glycolysis, and cell migration were detected. Next, we transiently transfected ErbB2 plasmid into MCF7 cells and detected FASN, LDHA protein levels, glycolysis and cell migration. Heregulin-β1 (HRG-β1) is an activator of ErbB2 and 2-deoxyglucose (2-DG) and oxamate (OX) are inhibitors of glycolysis. MCF7 cells were treated with HRG-β1 alone, HRG-β1 plus 2-DG, OX or cerulenin and glycolysis, and cell migration were measured. We found that FASN, ErbB2-high-expressing SK-BR-3 cells displayed higher levels of glycolysis and migration than FASN, ErbB2-low-expressing MCF7 cells. Inhibition of FASN by cerulenin impaired glycolysis and migration in SK-BR-3 cells. Transient overexpression of ErbB2 in MCF7 cells promotes glycolysis and migration. Moreover, 2-deoxyglucose (2-DG), oxamate (OX), or cerulenin partially reverses heregulin-β1 (HRG-β1)-induced glycolysis and migration in MCF7 cells. In conclusion, this study demonstrates that FASN, ErbB2-mediated glycolysis is required for breast cancer cell migration. These novel findings indicate that targeting FASN, ErbB2-mediated glycolysis may be a new approach to reverse breast cancer cell migration.

  6. Low-temperature Mechanical Properties of Bulk MgB2 Fabricated by Hot Isostatic Pressing

    NASA Astrophysics Data System (ADS)

    Murakami, A.; Teshima, H.; Naito, T.; Fujishiro, H.; Kudo, T.; Iwamoto, A.

    Mechanical properties ina MgB2superconducting bulk sample,whose packing ratio is 92%,fabricated by hot isostatic pressing (HIP)areevaluated at 77 K through bending tests.The fracture strength at 77 K is higher than at room temperature. From the bending test result at 77 K, the fracture strength of ideal bulk MgB2,whose packing ratio is 100%,is estimated. The fracture strength at very low temperature of the HIP bulk MgB2is also estimated from the bending test results at 77 K and room temperature.

  7. Development of Specific Inhibitors for Breast Cancer-Associated Variants of ErbB2

    DTIC Science & Technology

    2015-10-01

    project, we have expressed and purified the wild-type ErbB2 kinase domain and four cancer-associated mutants , one of which (G776C) has not previously been...reported. We have developed a kinase assay to be used in inhibitor screening. All four mutants are hyperactivated (relative to wild-type ErbB2...first objective is to test the cellular and in vitro kinase activity of all of the ErbB2 mutants . The second objective is to use computational screening

  8. Improving magnetic properties of MgB2 bulk superconductors by synthetic engine oil treatment

    NASA Astrophysics Data System (ADS)

    Taylan Koparan, E.; Savaskan, B.; Yanmaz, E.

    2016-08-01

    The present study focuses on the effects of standby time of the MgB2 samples immersed in synthetic engine oil on the critical current density (Jc(H)), magnetic field dependence of the pinning force density fp(b) and Tc performances of MgB2 bulk superconductors. Synthetic engine oil was used as a product which is cheap and a rich carbon source. Manufactured MgB2 pellet samples were immersed at different standby time of 30 min, 120 min, 300 min and 1440 min in synthetic engine oil after the first heating process. Finally, MgB2 samples immersed in synthetic engine oil were sintered at 1000 °C and kept for 15 min in Ar atmosphere. The critical current density of all of MgB2 samples immersed at different standby time in engine oil in whole field range was better than that of the pure MgB2 sample because of the number of the pinning centers. The MgB2 sample immersed at 300 min standby time in synthetic engine oil has the best performance compared to other samples. The Jc value for the pure sample is 2.0 × 103 A/cm2, whereas for the MgB2 sample immersed at 300 min standby time in engine oil the Jc is enhanced to 4.8 × 103A/cm2 at 5 K and 3 T. The superconducting transition temperature (Tc) did not change with the increasing standby time of the samples in synthetic engine oil at all. The best diamagnetic property was obtained from the sample which kept in synthetic engine oil for 300 min. Synthetic engine oil treatment results in remarkable improvement of the critical current density and pinning force performances of MgB2 superconductors. It was found that all MgB2 samples have a different pinning property at different measuring temperatures. Using synthetic engine oil as a product which is cheap and a rich carbon source in MgB2 bulk superconductors makes MgB2 samples immersed in synthetic engine oil a good candidate for industrial applications.

  9. Glass formation and crystallization of high lead content PbO-B2O3 compositions

    NASA Technical Reports Server (NTRS)

    Weinberg, Michael C.; Smith, Gary L.; Neilson, George F.

    1986-01-01

    The glass-forming and undercooling ability of PbO-B2O3 melts in the 2PbO.B2O3 to 4PbO.B2O3 composition range were studied. The glass formation propensities were investigated as a function of cooling rate and sample mass. A qualitative investigation of the crystallization process(es) preventing glass formation was made, and it was concluded that under normal circumstances heterogeneous nucleation was the common occurrence. Hence, it was concluded that such compositions are prime candidates for containerless experiments aboard the Space Shuttle.

  10. Aspirin Hydrolysis in Plasma Is a Variable Function of Butyrylcholinesterase and Platelet-activating Factor Acetylhydrolase 1b2 (PAFAH1b2)*

    PubMed Central

    Zhou, Gang; Marathe, Gopal K.; Hartiala, Jaana; Hazen, Stanley L.; Allayee, Hooman; Tang, W. H. Wilson; McIntyre, Thomas M.

    2013-01-01

    Aspirin is rapidly hydrolyzed within erythrocytes by a heterodimer of PAFAH1b2/PAFAH1b3 but also in plasma by an unidentified activity. Hydrolysis in both compartments was variable, with a 12-fold variation in plasma among 2226 Cleveland Clinic GeneBank patients. Platelet inhibition by aspirin was suppressed in plasma that rapidly hydrolyzed aspirin. Plasma aspirin hydrolysis was significantly higher in patients with coronary artery disease compared with control subjects (16.5 ± 4.4 versus 15.1 ± 3.7 nmol/ml/min; p = 3.4 × 10−8). A genome-wide association study of 2054 GeneBank subjects identified a single locus immediately adjacent to the BCHE (butyrylcholinesterase) gene associated with plasma aspirin hydrolytic activity (lead SNP, rs6445035; p = 9.1 × 10−17). However, its penetrance was low, and plasma from an individual with an inactivating mutation in BCHE still effectively hydrolyzed aspirin. A second aspirin hydrolase was identified in plasma, the purification of which showed it to be homomeric PAFAH1b2. This is distinct from the erythrocyte PAFAH1b2/PAFAH1b3 heterodimer. Inhibitors showed that both butyrylcholinesterase (BChE) and PAFAH1b2 contribute to aspirin hydrolysis in plasma, with variation primarily reflecting non-genetic variation of BChE activity. Therefore, aspirin is hydrolyzed in plasma by two enzymes, BChE and a new extracellular form of platelet-activating factor acetylhydrolase, PAFAH1b2. Hydrolytic effectiveness varies widely primarily from non-genetic variation of BChE activity that affects aspirin bioavailability in blood and the ability of aspirin to inhibit platelet aggregation. PMID:23508960

  11. German Special Operations in the 1944 Ardennes Offensive

    DTIC Science & Technology

    1994-06-03

    through the maze of traffic jams and poor roads, Skorzeny could not assemble them for an attack on the 19th, and accordingly the operation was...requesting care for his men.9 0 Von der Heydte traveled east on the 21st with his executive officer and runner towards Monschau, wlhich he a.bwned was In

  12. REACTOR AND NOVEL METHOD

    DOEpatents

    Young, G.J.; Ohlinger, L.A.

    1958-06-24

    A nuclear reactor of the type which uses a liquid fuel and a method of controlling such a reactor are described. The reactor is comprised essentially of a tank for containing the liquid fuel such as a slurry of discrete particles of fissionnble material suspended in a heavy water moderator, and a control means in the form of a disc of neutron absorbirg material disposed below the top surface of the slurry and parallel thereto. The diameter of the disc is slightly smaller than the diameter of the tank and the disc is perforated to permit a flow of the slurry therethrough. The function of the disc is to divide the body of slurry into two separate portions, the lower portion being of a critical size to sustain a nuclear chain reaction and the upper portion between the top surface of the slurry and the top surface of the disc being of a non-critical size. The method of operation is to raise the disc in the reactor until the lower portion of the slurry has reached a critical size when it is desired to initiate the reaction, and to lower the disc in the reactor to reduce the size of the lower active portion the slurry to below criticality when it is desired to stop the reaction.

  13. EBT reactor analysis

    SciTech Connect

    Uckan, N. A.; Jaeger, E. F.; Santoro, R. T.; Spong, D. A.; Uckan, T.; Owen, L. W.; Barnes, J. M.; McBride, J. B.

    1983-08-01

    This report summarizes the results of a recent ELMO Bumpy Torus (EBT) reactor study that includes ring and core plasma properties with consistent treatment of coupled ring-core stability criteria and power balance requirements. The principal finding is that constraints imposed by these coupling and other physics and technology considerations permit a broad operating window for reactor design optimization. Within this operating window, physics and engineering systems analysis and cost sensitivity studies indicate that reactors with <..beta../sub core/> approx. 6 to 10%, P approx. 1200 to 1700 MW(e), wall loading approx. 1.0 to 2.5 MW/m/sup 2/, and recirculating power fraction (including ring-sustaining power and all other reactors auxiliaries) approx. 10 to 15% are possible. A number of concept improvements are also proposed that are found to offer the potential for further improvement of the reactor size and parameters. These include, but are not limited to, the use of: (1) supplementary coils or noncircular mirror coils to improve magnetic geometry and reduce size, (2) energetic ion rings to improve ring power requirements, (3) positive potential to enhance confinement and reduce size, and (4) profile control to improve stability and overall fusion power density.

  14. Methanation assembly using multiple reactors

    DOEpatents

    Jahnke, Fred C.; Parab, Sanjay C.

    2007-07-24

    A methanation assembly for use with a water supply and a gas supply containing gas to be methanated in which a reactor assembly has a plurality of methanation reactors each for methanating gas input to the assembly and a gas delivery and cooling assembly adapted to deliver gas from the gas supply to each of said methanation reactors and to combine water from the water supply with the output of each methanation reactor being conveyed to a next methanation reactor and carry the mixture to such next methanation reactor.

  15. Abnormal development of the cerebral cortex and cerebellum in the setting of lamin B2 deficiency

    PubMed Central

    Coffinier, Catherine; Chang, Sandy Y.; Nobumori, Chika; Tu, Yiping; Farber, Emily A.; Toth, Julia I.; Fong, Loren G.; Young, Stephen G.

    2010-01-01

    Nuclear lamins are components of the nuclear lamina, a structural scaffolding for the cell nucleus. Defects in lamins A and C cause an array of human diseases, including muscular dystrophy, lipodystrophy, and progeria, but no diseases have been linked to the loss of lamins B1 or B2. To explore the functional relevance of lamin B2, we generated lamin B2-deficient mice and found that they have severe brain abnormalities resembling lissencephaly, with abnormal layering of neurons in the cerebral cortex and cerebellum. This neuronal layering abnormality is due to defective neuronal migration, a process that is dependent on the organized movement of the nucleus within the cell. These studies establish an essential function for lamin B2 in neuronal migration and brain development. PMID:20145110

  16. Superior homogeneity of trapped magnetic field in superconducting MgB2 bulk magnets

    NASA Astrophysics Data System (ADS)

    Ishihara, A.; Akasaka, T.; Tomita, M.; Kishio, K.

    2017-03-01

    Homogeneity of trapped magnetic field in radial and circumferential directions of high temperature superconducting bulk magnets, MgB2 (T c ˜38.3 K) and YBa2Cu3O y (T c ˜91.5 K), have been measured. In polycrystalline MgB2 bulks, the circularity of trapped magnetic field in a cylindrical disk is over 97% at 20-32.5 K, while that of YBa2Cu3O y was ˜87% at 77 K. Magnetic field distribution of MgB2 bulk was satisfactorily homogeneous and these measurements suggest MgB2 bulks with highly efficient cryocoolers should be very useful for novel high field permanent magnet applications.

  17. Multiband behavior signature in Hf0.97V0.03B2 superconductor compound

    NASA Astrophysics Data System (ADS)

    Renosto, Sergio; Cigarroa, Orlando; Grant, Ted; Dos Santos, Carlos A. Moreira; Aguiar, J. Albino; Fisk, Zachary; Machado, A. Jefferson

    2014-03-01

    Isostructural MgB2 compounds which crystallizes in AlB2 prototype structure have been received much attention due to its potential for exhibit multiband behavior. Although there are many MB2 compounds (M - refractory metal) superconductivity it is too hard of find in the MB2 compounds. However, previous studies have been shown that Zr1-xVxB2 exhibit superconducting behavior with signature of multiband. Within this context, in this work, we are showing preliminary results of the partial substitution of Hf for V in the Hf1-xVxB2 with bulk superconductivity. Hall effect, magnetization, specific heat and resistivity measurements strongly suggest that this new compound represents a new example of multiband behavior.

  18. ErbB2 is required for cardiomyocyte proliferation in murine neonatal hearts

    PubMed Central

    Ma, Hong; Yin, Chaoying; Zhang, Yingao; Qian, Li; Liu, Jiandong

    2017-01-01

    It has been long recognized that the mammalian heart loses its proliferative capacity soon after birth, yet, the molecular basis of this loss of cardiac proliferation postnatally is largely unknown. In this study, we found that cardiac ErbB2, a member of the epidermal growth factor receptor family, exhibits a rapid and dramatic decline in expression at the neonatal stage. We further demonstrate that conditional ablation of ErbB2 in the ventricular myocardium results in upregulation of negative cell cycle regulators and a significant reduction in cardiomyocyte proliferation during the narrow neonatal proliferative time window. Together, our data reveal a positive correlation between the expression levels of ErbB2 with neonatal cardiomyocyte proliferation and suggest that reduction in cardiac ErbB2 expression may contribute to the loss of postnatal cardiomyocyte proliferative capacity. PMID:27390088

  19. 26 CFR 1.662(b)-2 - Character of amounts; when charitable contributions are made.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Income Or Which Distribute Corpus § 1.662(b)-2 Character of amounts; when charitable contributions are... instrument and local law capital gains are added to corpus. During the taxable year the trust...

  20. EphB2 guides axons at the midline and is necessary for normal vestibular function

    NASA Technical Reports Server (NTRS)

    Cowan, C. A.; Yokoyama, N.; Bianchi, L. M.; Henkemeyer, M.; Fritzsch, B.

    2000-01-01

    Mice lacking the EphB2 receptor tyrosine kinase display a cell-autonomous, strain-specific circling behavior that is associated with vestibular phenotypes. In mutant embryos, the contralateral inner ear efferent growth cones exhibit inappropriate pathway selection at the midline, while in mutant adults, the endolymph-filled lumen of the semicircular canals is severely reduced. EphB2 is expressed in the endolymph-producing dark cells in the inner ear epithelium, and these cells show ultrastructural defects in the mutants. A molecular link to fluid regulation is provided by demonstrating that PDZ domain-containing proteins that bind the C termini of EphB2 and B-ephrins can also recognize the cytoplasmic tails of anion exchangers and aquaporins. This suggests EphB2 may regulate ionic homeostasis and endolymph fluid production through macromolecular associations with membrane channels that transport chloride, bicarbonate, and water.

  1. Safety Analysis Report: X17B2 beamline Synchrotron Medical Research Facility

    SciTech Connect

    Gmuer, N.F.; Thomlinson, W.

    1990-02-01

    This report contains a safety analysis for the X17B2 beamline synchrotron medical research facility. Health hazards, risk assessment and building systems are discussed. Reference is made to transvenous coronary angiography. (LSP)

  2. 2. VIEW OF NORTHERN WATER TANK (FEATURE B2), FACING SOUTH. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. VIEW OF NORTHERN WATER TANK (FEATURE B-2), FACING SOUTH. THE ADIT ROAD IS SHOWN IN THE RIGHT SIDE OF THE PHOTO. - Nevada Lucky Tiger Mill & Mine, Water Tanks, East slope of Buckskin Mountain, Paradise Valley, Humboldt County, NV

  3. Proton Mobility in b2 Ion Formation and Fragmentation Reactions of Histidine-Containing Peptides

    NASA Astrophysics Data System (ADS)

    Nelson, Carissa R.; Abutokaikah, Maha T.; Harrison, Alex G.; Bythell, Benjamin J.

    2016-03-01

    A detailed energy-resolved study of the fragmentation reactions of protonated histidine-containing peptides and their b2 ions has been undertaken. Density functional theory calculations were utilized to predict how the fragmentation reactions occur so that we might discern why the mass spectra demonstrated particular energy dependencies. We compare our results to the current literature and to synthetic b2 ion standards. We show that the position of the His residue does affect the identity of the subsequent b2 ion (diketopiperazine versus oxazolone versus lactam) and that energy-resolved CID can distinguish these isomeric products based on their fragmentation energetics. The histidine side chain facilitates every major transformation except trans-cis isomerization of the first amide bond, a necessary prerequisite to diketopiperazine b2 ion formation. Despite this lack of catalyzation, trans-cis isomerization is predicted to be facile. Concomitantly, the subsequent amide bond cleavage reaction is rate-limiting.

  4. Superconducting characteristics of short MgB2 wires of long level sensor for liquid hydrogen

    NASA Astrophysics Data System (ADS)

    Takeda, M.; Inoue, Y.; Maekawa, K.; Matsuno, Y.; Fujikawa, S.; Kumakura, H.

    2015-12-01

    To establish the worldwide storage and marine transport of hydrogen, it is important to develop a high-precision and long level sensor, such as a superconducting magnesium diboride (MgB2) level sensor for large liquid hydrogen (LH2) tanks on board ships. Three 1.7- m-long MgB2 wires were fabricated by an in situ method, and the superconducting characteristics of twenty-four 20-mm-long MgB2 wires on the 1.7-m-long wires were studied. In addition, the static level-detecting characteristics of five 500-mm-long MgB2 level sensors were evaluated under atmospheric pressure.

  5. 76 FR 54772 - Federal Management Regulation; FMR Bulletin PBS-2011-B2; Redesignations of Federal Buildings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-02

    ... ADMINISTRATION Federal Management Regulation; FMR Bulletin PBS-2011-B2; Redesignations of Federal Buildings AGENCY: Public Buildings Service (P), General Services Administration. ACTION: Notice of a bulletin. SUMMARY: The attached bulletin announces the designation and redesignation of two Federal...

  6. Looking Southwest at Reactor Box Furnaces With Reactor Boxes and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking Southwest at Reactor Box Furnaces With Reactor Boxes and Repossessed Uranium in Recycle Recovery Building - Hematite Fuel Fabrication Facility, Recycle Recovery Building, 3300 State Road P, Festus, Jefferson County, MO

  7. Amygdala EphB2 Signaling Regulates Glutamatergic Neuron Maturation and Innate Fear

    PubMed Central

    Zhu, Xiao-Na; Liu, Xian-Dong; Zhuang, Hanyi; Henkemeyer, Mark

    2016-01-01

    The amygdala serves as emotional center to mediate innate fear behaviors that are reflected through neuronal responses to environmental aversive cues. However, the molecular mechanism underlying the initial neuron responses is poorly understood. In this study, we monitored the innate defensive responses to aversive stimuli of either elevated plus maze or predator odor in juvenile mice and found that glutamatergic neurons were activated in amygdala. Loss of EphB2, a receptor tyrosine kinase expressed in amygdala neurons, suppressed the reactions and led to defects in spine morphogenesis and fear behaviors. We further found a coupling of spinogenesis with these threat cues induced neuron activation in developing amygdala that was controlled by EphB2. A constitutively active form of EphB2 was sufficient to rescue the behavioral and morphological defects caused by ablation of ephrin-B3, a brain-enriched ligand to EphB2. These data suggest that kinase-dependent EphB2 intracellular signaling plays a major role for innate fear responses during the critical developing period, in which spinogenesis in amygdala glutamatergic neurons was involved. SIGNIFICANCE STATEMENT Generation of innate fear responses to threat as an evolutionally conserved brain feature relies on development of functional neural circuit in amygdala, but the molecular mechanism remains largely unknown. We here identify that EphB2 receptor tyrosine kinase, which is specifically expressed in glutamatergic neurons, is required for the innate fear responses in the neonatal brain. We further reveal that EphB2 mediates coordination of spinogenesis and neuron activation in amygdala during the critical period for the innate fear. EphB2 catalytic activity plays a major role for the behavior upon EphB–ephrin-B3 binding and transnucleus neuronal connections. Our work thus indicates an essential synaptic molecular signaling within amygdala that controls synapse development and helps bring about innate fear emotions

  8. An ANFIS-based on B2C electronic commerce transaction

    NASA Astrophysics Data System (ADS)

    Lin, Juan; Liu, Chenlian; Guo, Yongning

    2014-10-01

    The purpose of this study is to use an adaptive-network-based fuzzy inference system to model a fuzzy logic-based system (FIS) for supporting decision-making process in B2C electronic commerce transaction. Firstly we introduce FIS in B2C electronic commerce transaction and ANFIS. Then we use ANFIS to model FIS with different membership functions(MF). Lastly we give a conclusion.

  9. RelB/NF-κB2 regulates corticotropin-releasing hormone in the human placenta.

    PubMed

    Wang, Bingbing; Parobchak, Nataliya; Rosen, Todd

    2012-08-01

    Placental CRH may be part of a clock that governs the length of human gestation. The mechanism underlying differential regulation of CRH in the human placenta is poorly understood. We report here that constitutively activated RelB/nuclear factor-κB2 (NF-κB)-2 (p100/p52) acts as an endogenous stimulatory signal to regulate CRH by binding to an NF-κB enhancer of CRH gene promoter in the human placenta. Nuclear staining of NF-κB2 and RelB in villous syncytiotrophoblasts and cytotrophoblasts was coupled with cytoplasmic CRH in syncytial knots of cytotrophoblasts. Chromatin immunoprecipitation identified that CRH gene associated with both RelB and NF-κB2 (p52). Dexamethasone increased synthesis and nuclear translocation of RelB and NF-κB2 (p52) and their association with the CRH gene. In contrast, progesterone, a down-regulator of placental CRH, repressed NF-κB2 (p100) processing, nuclear translocation of RelB and NF-κB2 (p52), and their association with the CRH gene. Luciferase reporter assay determined that the NF-κB enhancer of CRH was sufficient to regulate transcriptional activity of a heterologous promoter in primary cytotrophoblasts. RNA interference-mediated repression of RelB or NF-κB2 resulted in significant inhibition of CRH at both transcriptional and translational levels and prevented the dexamethasone-mediated up-regulation of CRH transcription and translation. These results suggest that the noncanonical NF-κB pathway regulates CRH production in the human placenta and is responsible for the positive regulation of CRH by glucocorticoids.

  10. An ANFIS-based on B2C electronic commerce transaction

    SciTech Connect

    Lin, Juan; Liu, Chenlian; Guo, Yongning

    2014-10-06

    The purpose of this study is to use an adaptive-network-based fuzzy inference system to model a fuzzy logic-based system (FIS) for supporting decision-making process in B2C electronic commerce transaction. Firstly we introduce FIS in B2C electronic commerce transaction and ANFIS. Then we use ANFIS to model FIS with different membership functions(MF). Lastly we give a conclusion.

  11. Reactor for exothermic reactions

    DOEpatents

    Smith, Jr., Lawrence A.; Hearn, Dennis; Jones, Jr., Edward M.

    1993-01-01

    A liquid phase process for oligomerization of C.sub.4 and C.sub.5 isoolefins or the etherification thereof with C.sub.1 to C.sub.6 alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120.degree. to 300.degree. F. Wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled.

  12. Reactor for exothermic reactions

    DOEpatents

    Smith, L.A. Jr.; Hearn, D.; Jones, E.M. Jr.

    1993-03-02

    A liquid phase process is described for oligomerization of C[sub 4] and C[sub 5] isoolefins or the etherification thereof with C[sub 1] to C[sub 6] alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120 to 300 F. Wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled.

  13. A NEUTRONIC REACTOR

    DOEpatents

    Luebke, E.A.; Vandenberg, L.B.

    1959-09-01

    A nuclear reactor for producing thermoelectric power is described. The reactor core comprises a series of thermoelectric assemblies, each assembly including fissionable fuel as an active element to form a hot junction and a thermocouple. The assemblies are disposed parallel to each other to form spaces and means are included for Introducing an electrically conductive coolant between the assemblies to form cold junctions of the thermocouples. An electromotive force is developed across the entire series of the thermoelectric assemblies due to fission heat generated in the fuel causing a current to flow perpendicular to the flow of coolant and is distributed to a load outside of the reactor by means of bus bars electrically connected to the outermost thermoelectric assembly.

  14. MERCHANT MARINE SHIP REACTOR

    DOEpatents

    Mumm, J.F.; North, D.C. Jr.; Rock, H.R.; Geston, D.K.

    1961-05-01

    A nuclear reactor is described for use in a merchant marine ship. The reactor is of pressurized light water cooled and moderated design in which three passes of the water through the core in successive regions of low, intermediate, and high heat generation and downflow in a fuel region are made. The foregoing design makes a compact reactor construction with extended core life. The core has an egg-crate lattice containing the fuel elements confined between a lower flow baffle and upper grid plate, with the latter serving also as part of a turn- around manifold from which the entire coolant is distributed into the outer fuel elements for the second pass through the core. The inner fuel elements are cooled in the third pass.

  15. Merchant Marine Ship Reactor

    DOEpatents

    Sankovich, M. F.; Mumm, J. F.; North, Jr, D. C.; Rock, H. R.; Gestson, D. K.

    1961-05-01

    A nuclear reactor for use in a merchant marine ship is described. The reactor is of pressurized, light water cooled and moderated design in which three passes of the water through the core in successive regions of low, intermediate, and high heat generation and downflow in a fuel region are made. The design makes a compact reactor construction with extended core life. The core has an egg-crate lattice containing the fuel elements that are confined between a lower flow baffle and upper grid plate, with the latter serving also as part of a turn- around manifold from which the entire coolant is distributed into the outer fuel elements for the second pass through the core. The inner fuel elements are cooled in the third pass. (AEC)

  16. Heat dissipating nuclear reactor

    DOEpatents

    Hunsbedt, A.; Lazarus, J.D.

    1985-11-21

    Disclosed is a nuclear reactor containment adapted to retain and cool core debris in the unlikely event of a core meltdown and subsequent breach in the reactor vessel. The reactor vessel is seated in a cavity which has a thick metal sidewall that is integral with a thick metal basemat at the bottom of the cavity. The basemat extends beyond the perimeter of the cavity sidewall. Underneath the basemat is a porous bed with water pipes and steam pipes running into it. Water is introduced into the bed and converted into steam which is vented to the atmosphere. A plurality of metal pilings in the form of H-beams extend from the metal base plate downwardly and outwardly into the earth.

  17. Nuclear reactor safety device

    DOEpatents

    Hutter, Ernest

    1986-01-01

    A safety device is disclosed for use in a nuclear reactor for axially repositioning a control rod with respect to the reactor core in the event of an upward thermal excursion. Such safety device comprises a laminated helical ribbon configured as a tube-like helical coil having contiguous helical turns with slidably abutting edges. The helical coil is disclosed as a portion of a drive member connected axially to the control rod. The laminated ribbon is formed of outer and inner laminae. The material of the outer lamina has a greater thermal coefficient of expansion than the material of the inner lamina. In the event of an upward thermal excursion, the laminated helical coil curls inwardly to a smaller diameter. Such inward curling causes the total length of the helical coil to increase by a substantial increment, so that the control rod is axially repositioned by a corresponding amount to reduce the power output of the reactor.

  18. Thermionic Reactor Design Studies

    SciTech Connect

    Schock, Alfred

    1994-08-01

    Paper presented at the 29th IECEC in Monterey, CA in August 1994. The present paper describes some of the author's conceptual designs and their rationale, and the special analytical techniques developed to analyze their (thermionic reactor) performance. The basic designs, first published in 1963, are based on single-cell converters, either double-ended diodes extending over the full height of the reactor core or single-ended diodes extending over half the core height. In that respect they are similar to the thermionic fuel elements employed in the Topaz-2 reactor subsequently developed in the Soviet Union, copies of which were recently imported by the U.S. As in the Topaz-2 case, electrically heated steady-state performance tests of the converters are possible before fueling.

  19. Dynamic bed reactor

    SciTech Connect

    Stormo, K.E.

    1996-07-02

    A dynamic bed reactor is disclosed in which a compressible open cell foam matrix is periodically compressed and expanded to move a liquid or fluid through the matrix. In preferred embodiments, the matrix contains an active material such as an enzyme, biological cell, chelating agent, oligonucleotide, adsorbent or other material that acts upon the liquid or fluid passing through the matrix. The active material may be physically immobilized in the matrix, or attached by covalent or ionic bonds. Microbeads, substantially all of which have diameters less than 50 microns, can be used to immobilize the active material in the matrix and further improve reactor efficiency. A particularly preferred matrix is made of open cell polyurethane foam, which adsorbs pollutants such as polychlorophenol or o-nitrophenol. The reactors of the present invention allow unidirectional non-laminar flow through the matrix, and promote intimate exposure of liquid reactants to active agents such as microorganisms immobilized in the matrix. 27 figs.

  20. Dynamic bed reactor

    SciTech Connect

    Stormo, Keith E.

    1996-07-02

    A dynamic bed reactor is disclosed in which a compressible open cell foam matrix is periodically compressed and expanded to move a liquid or fluid through the matrix. In preferred embodiments, the matrix contains an active material such as an enzyme, biological cell, chelating agent, oligonucleotide, adsorbent or other material that acts upon the liquid or fluid passing through the matrix. The active material may be physically immobilized in the matrix, or attached by covalent or ionic bonds. Microbeads, substantially all of which have diameters less than 50 microns, can be used to immobilize the active material in the matrix and further improve reactor efficiency. A particularly preferred matrix is made of open cell polyurethane foam, which adsorbs pollutants such as polychlorophenol or o-nitrophenol. The reactors of the present invention allow unidirectional non-laminar flow through the matrix, and promote intimate exposure of liquid reactants to active agents such as microorganisms immobilized in the matrix.

  1. Heat dissipating nuclear reactor

    DOEpatents

    Hunsbedt, Anstein; Lazarus, Jonathan D.

    1987-01-01

    Disclosed is a nuclear reactor containment adapted to retain and cool core debris in the unlikely event of a core meltdown and subsequent breach in the reactor vessel. The reactor vessel is seated in a cavity which has a thick metal sidewall that is integral with a thick metal basemat at the bottom of the cavity. The basemat extends beyond the perimeter of the cavity sidewall. Underneath the basemat is a porous bed with water pipes and steam pipes running into it. Water is introduced into the bed and converted into steam which is vented to the atmosphere. A plurality of metal pilings in the form of H-beams extends from the metal base plate downwardly and outwardly into the earth.

  2. REACTOR CONTROL DEVICE

    DOEpatents

    Graham, R.H.

    1962-09-01

    A wholly mechanical compact control device is designed for automatically rendering the core of a fission reactor subcritical in response to core temperatures in excess of the design operating temperature limit. The control device comprises an expansible bellows interposed between the base of a channel in a reactor core and the inner end of a fuel cylinder therein which is normally resiliently urged inwardly. The bellows contains a working fluid which undergoes a liquid to vapor phase change at a temperature substantially equal to the design temperature limit. Hence, the bellows abruptiy expands at this limiting temperature to force the fuel cylinder outward and render the core subcritical. The control device is particularly applicable to aircraft propulsion reactor service. (AEC)

  3. Erythropoietin promotes bone formation through EphrinB2/EphB4 signaling.

    PubMed

    Li, C; Shi, C; Kim, J; Chen, Y; Ni, S; Jiang, L; Zheng, C; Li, D; Hou, J; Taichman, R S; Sun, H

    2015-03-01

    Recent studies have demonstrated that erythropoietin (EPO) has extensive nonhematopoietic biological functions. However, little is known about how EPO regulates bone formation, although several studies suggested that EPO can affect bone homeostasis. In this study, we investigated the effects of EPO on the communication between osteoclasts and osteoblasts through the ephrinB2/EphB4 signaling pathway. We found that EPO slightly promotes osteoblastic differentiation with the increased expression of EphB4 in ST2 cells. However, EPO increased the expression of Nfatc1 and ephrinB2 but decreased the expression of Mmp9 in RAW264.7 cells, resulting in an increase of ephrinB2-expressing osteoclasts and a decrease in resorption activity. The stimulation of ephrinB2/EphB4 signaling via ephrinB2-Fc significantly promoted EPO-mediated osteoblastic differentiation in ST2 cells. EphB4 knockdown through EphB4 shRNA inhibited EPO-mediated osteoblastic phenotypes. Furthermore, in vivo assays clearly demonstrated that EPO efficiently induces new bone formation in the alveolar bone regeneration model. Taken together, these results suggest that ephrinB2/EphB4 signaling may play an important role in EPO-mediated bone formation.

  4. Mechanical and tribological characterization of TiB2 thin films.

    PubMed

    Silva, F J G; Casais, R C B; Martinho, R P; Baptista, A P M

    2012-12-01

    Titanium Diboride (TiB2) presents high mechanical and physical properties. Some wear studies were also carried out in order to evaluate its tribological properties. One of the most popular wear tests for thin films is the ball-cratering configuration. This work was focused on the study of the tribological properties of TiB2 thin films using micro-abrasion tests and following the BS EN 1071-6: 2007 standard. Due to high hardness usually patented by these films, diamond was selected as abrasive on micro-abrasion tests. Micro-abrasion wear tests were performed under five different durations, using the same normal load, speed rotation and ball. Films were deposited by unbalanced magnetron sputtering Physical Vapour Deposition (PVD) technique using TiB2 targets. TiB2 films were characterized using different methods as Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), Atomic Force Microscopy (AFM), X-ray Diffraction (XRD), Electron Probe Micro-Analyser (EPMA), Ultra Micro Hardness and Scratch-test Analysis, allowing to confirm that TiB2 presents adequate mechanical and physical properties. Ratio between hardness (coating and abrasive particles), wear resistance and wear coefficient were studied, showing that TiB2 films shows excellent properties for tribological applications.

  5. Critical determination of the frequency of c-erbB-2 amplification in breast cancer.

    PubMed Central

    Hubbard, A. L.; Doris, C. P.; Thompson, A. M.; Chetty, U.; Anderson, T. J.

    1994-01-01

    Tissues from 323 methacarn-fixed and paraffin-embedded breast cancers were assessed for c-erbB-2 gene amplification by differential polymerase chain reaction (dPCR). The sensitivity of dPCR was ascertained using cell lines with c-erbB-2 amplification, and the relationship between dPCR ratio value and gene copy number was established. In clinical material the technique was not affected by the DNA contribution of normal tissue elements or by cancer DNA ploidy change. c-erbB-2 gene amplification was detected in 55% of invasive cancers and in 66% of in situ cancers. c-erbB-2 protein overexpression in breast cancer cells, as determined by specific immunohistochemistry, was only detected in 11% of invasive cancers and 43% of in situ cancers. Comparisons show that a substantial number of cancers with c-erbB-2 amplification lack detectable protein overexpression. This illustrates the complex nature of c-erbB-2 gene disregulation in cancer and suggests that multiple combinations of biological events and consequences are possible. Images Figure 3 PMID:7915911

  6. SerpinB2 regulates stromal remodelling and local invasion in pancreatic cancer.

    PubMed

    Harris, N L E; Vennin, C; Conway, J R W; Vine, K L; Pinese, M; Cowley, M J; Shearer, R F; Lucas, M C; Herrmann, D; Allam, A H; Pajic, M; Morton, J P; Biankin, A V; Ranson, M; Timpson, P; Saunders, D N

    2017-03-27

    Pancreatic cancer has a devastating prognosis, with an overall 5-year survival rate of ~8%, restricted treatment options and characteristic molecular heterogeneity. SerpinB2 expression, particularly in the stromal compartment, is associated with reduced metastasis and prolonged survival in pancreatic ductal adenocarcinoma (PDAC) and our genomic analysis revealed that SERPINB2 is frequently deleted in PDAC. We show that SerpinB2 is required by stromal cells for normal collagen remodelling in vitro, regulating fibroblast interaction and engagement with collagen in the contracting matrix. In a pancreatic cancer allograft model, co-injection of PDAC cancer cells and SerpinB2(-/-) mouse embryonic fibroblasts (MEFs) resulted in increased tumour growth, aberrant remodelling of the extracellular matrix (ECM) and increased local invasion from the primary tumour. These tumours also displayed elevated proteolytic activity of the primary biochemical target of SerpinB2-urokinase plasminogen activator (uPA). In a large cohort of patients with resected PDAC, we show that increasing uPA mRNA expression was significantly associated with poorer survival following pancreatectomy. This study establishes a novel role for SerpinB2 in the stromal compartment in PDAC invasion through regulation of stromal remodelling and highlights the SerpinB2/uPA axis for further investigation as a potential therapeutic target in pancreatic cancer.Oncogene advance online publication, 27 March 2017; doi:10.1038/onc.2017.63.

  7. High critical currents in iron-clad superconducting MgB2 wires.

    PubMed

    Jin, S; Mavoori, H; Bower, C; van Dover, R B

    2001-05-31

    Technically useful bulk superconductors must have high transport critical current densities, Jc, at operating temperatures. They also require a normal metal cladding to provide parallel electrical conduction, thermal stabilization, and mechanical protection of the generally brittle superconductor cores. The recent discovery of superconductivity at 39 K in magnesium diboride (MgB2) presents a new possibility for significant bulk applications, but many critical issues relevant for practical wires remain unresolved. In particular, MgB2 is mechanically hard and brittle and therefore not amenable to drawing into the desired fine-wire geometry. Even the synthesis of moderately dense, bulk MgB2 attaining 39 K superconductivity is a challenge because of the volatility and reactivity of magnesium. Here we report the successful fabrication of dense, metal-clad superconducting MgB2 wires, and demonstrate a transport Jc in excess of 85,000 A cm-2 at 4.2 K. Our iron-clad fabrication technique takes place at ambient pressure, yet produces dense MgB2 with little loss of stoichiometry. While searching for a suitable cladding material, we found that other materials dramatically reduced the critical current, showing that although MgB2 itself does not show the 'weak-link' effect characteristic of the high-Tc superconductors, contamination does result in weak-link-like behaviour.

  8. Crystal Structures, Stabilities, Electronic Properties, and Hardness of MoB2: First-Principles Calculations.

    PubMed

    Ding, Li-Ping; Shao, Peng; Zhang, Fang-Hui; Lu, Cheng; Ding, Lei; Ning, Shu Ya; Huang, Xiao Fen

    2016-07-18

    On the basis of the first-principles techniques, we perform the structure prediction for MoB2. Accordingly, a new ground-state crystal structure WB2 (P63/mmc, 2 fu/cell) is uncovered. The experimental synthesized rhombohedral R3̅m and hexagonal AlB2, as well as theoretical predicted RuB2 structures, are no longer the most favorite structures. By analyzing the elastic constants, formation enthalpies, and phonon dispersion, we find that the WB2 phase is thermodynamically and mechanically stable. The high bulk modulus B, shear modulus G, low Poisson's ratio ν, and small B/G ratio are benefit to its low compressibility. When the pressure is 10 GPa, a phase transition is observed between the WB2-MoB2 and the rhombohedral R3̅m MoB2 phases. By analyzing the density of states and electron density, we find that the strong covalent is formed in MoB2 compounds, which contributes a great deal to its low compressibility. Furthermore, the low compressibility is also correlated with the local buckled structure.

  9. Wettability and Reactivity of ZrB2 Substrates with Liquid Al

    NASA Astrophysics Data System (ADS)

    Nowak, R.; Sobczak, N.; Bruzda, G.; Wojewoda-Budka, J.; Litynska-Dobrzynska, L.; Homa, M.; Kaban, I.; Xi, L.; Jaworska, L.

    2016-08-01

    Wetting characteristics of the Al/ZrB2 system were experimentally determined by the sessile drop method with application of separate heating of the ZrB2 and Al samples and combined with in situ cleaning of Al drop from native oxide film directly in vacuum chamber. The tests were performed in ultrahigh vacuum of 10-6 mbar at temperatures 710, 800, and 900 °C as well as in flowing inert gas (Ar) atmosphere at 1400 °C. The results evidenced that liquid Al does not wet ZrB2 substrate at 710 and 800 °C, forming high contact angles ( θ) of 128° and 120°, respectively. At 900 °C, wetting phenomenon ( θ < 90°) occurs in 29th minute and the contact angle decreases monotonically to the final value of 80°. At 1400 °C, wetting takes place immediately after drop deposition with a fast decrease in the contact angle to 76°. The solidified Al/ZrB2 couples were studied by scanning and transmission electron microscopy coupled with x-ray energy diffraction spectroscopy. Structural characterization revealed that only in the Al/ZrB2 couple produced at the highest temperature of 1400 °C new phases (Al3Zr, AlB2 and α-Al2O3) were formed.

  10. Erythropoietin Promotes Bone Formation through EphrinB2/EphB4 Signaling

    PubMed Central

    Li, C.; Shi, C.; Kim, J.; Chen, Y.; Ni, S.; Jiang, L.; Zheng, C.; Li, D.; Hou, J.; Sun, H.

    2015-01-01

    Recent studies have demonstrated that erythropoietin (EPO) has extensive nonhematopoietic biological functions. However, little is known about how EPO regulates bone formation, although several studies suggested that EPO can affect bone homeostasis. In this study, we investigated the effects of EPO on the communication between osteoclasts and osteoblasts through the ephrinB2/EphB4 signaling pathway. We found that EPO slightly promotes osteoblastic differentiation with the increased expression of EphB4 in ST2 cells. However, EPO increased the expression of Nfatc1 and ephrinB2 but decreased the expression of Mmp9 in RAW264.7 cells, resulting in an increase of ephrinB2-expressing osteoclasts and a decrease in resorption activity. The stimulation of ephrinB2/EphB4 signaling via ephrinB2-Fc significantly promoted EPO-mediated osteoblastic differentiation in ST2 cells. EphB4 knockdown through EphB4 shRNA inhibited EPO-mediated osteoblastic phenotypes. Furthermore, in vivo assays clearly demonstrated that EPO efficiently induces new bone formation in the alveolar bone regeneration model. Taken together, these results suggest that ephrinB2/EphB4 signaling may play an important role in EPO-mediated bone formation. PMID:25586589

  11. An anti-ErbB2 fully human antibody circumvents trastuzumab resistance

    PubMed Central

    Wang, Chao; Wang, Huajing; Yang, Yang; Chong, Xiaodan; Xia, Tian; Meng, Yanchun; Wang, Yuxiao; Lu, Cuihua; Zhou, Lijun; Li, Bohua

    2016-01-01

    Trastuzumab, an anti-HER2/ErbB2 humanized antibody, has shown great clinical benefits in ErbB2-positive breast cancer treatment. Despite of its effectiveness, response rate to trastuzumab is limited and resistance is common. Here, we developed a new anti-ErbB2 antibody, denoted as H2-18, which was isolated from a phage display human antibody library. Previous studies have demonstrated that trastuzumab recognizes the juxtamembrane region of domain IV, and pertuzumab, another humanized ErbB2-specific antibody, binds to ErbB2 near the center of domain II. Our crystallographic analysis showed that the epitope recognized by H2-18 is within domain I of the ErbB2 molecule. H2-18 potently induced programmed cell death (PCD) in both trastuzumab-sensitive and -resistant breast cancer cell lines, while trastuzumab and pertuzumab, either used alone or in combination, only exhibits very weak PCD-inducing activity. More importantly, H2-18 could inhibit the growth of trastuzumab-resistant breast cancer cells far more effectively than trastuzumab plus pertuzumab, both in vitro and in vivo. In conclusion, H2-18 shows a unique ability to overcome trastuzumab resistance, suggesting that it has the great potential to be translated to the clinic. PMID:27564098

  12. Cyclin B2 and p53 control proper timing of centrosome separation

    PubMed Central

    Nam, Hyun-Ja; van Deursen, Jan M.

    2015-01-01

    Cyclins Bl and B2 are frequently elevated in human cancers and are associated with tumour aggressiveness and poor clinical outcome; however, whether and how B-type cyclins drive tumorigenesis is unknown. Here we show that cyclin Bl and B2 transgenic mice are highly prone to tumours, including tumour types where B-type cyclins serve as prognosticators. Cyclins Bl and B2 both induce aneuploidy when overexpressed but through distinct mechanisms, with cyclin Bl inhibiting separase activation, leading to anaphase bridges, and cyclin B2 triggering aurora-A-mediated Plkl hyperactivation, resulting in accelerated centrosome separation and lagging chromosomes. Complementary experiments revealed that cyclin B2 and p53 act antagonistically to control aurora-A-mediated centrosome splitting and accurate chromosome segregation in normal cells. These data demonstrate a causative link between B-type cyclin overexpression and tumour pathophysiology, and uncover previously unknown functions of cyclin B2 and p53 in centrosome separation that may be perturbed in many human cancers. PMID:24776885

  13. EphrinB2 drives perivascular invasion and proliferation of glioblastoma stem-like cells

    PubMed Central

    Krusche, Benjamin; Ottone, Cristina; Clements, Melanie P; Johnstone, Ewan R; Goetsch, Katrin; Lieven, Huang; Mota, Silvia G; Singh, Poonam; Khadayate, Sanjay; Ashraf, Azhaar; Davies, Timothy; Pollard, Steven M; De Paola, Vincenzo; Roncaroli, Federico; Martinez-Torrecuadrada, Jorge; Bertone, Paul; Parrinello, Simona

    2016-01-01

    Glioblastomas (GBM) are aggressive and therapy-resistant brain tumours, which contain a subpopulation of tumour-propagating glioblastoma stem-like cells (GSC) thought to drive progression and recurrence. Diffuse invasion of the brain parenchyma, including along preexisting blood vessels, is a leading cause of therapeutic resistance, but the mechanisms remain unclear. Here, we show that ephrin-B2 mediates GSC perivascular invasion. Intravital imaging, coupled with mechanistic studies in murine GBM models and patient-derived GSC, revealed that endothelial ephrin-B2 compartmentalises non-tumourigenic cells. In contrast, upregulation of the same ephrin-B2 ligand in GSC enabled perivascular migration through homotypic forward signalling. Surprisingly, ephrin-B2 reverse signalling also promoted tumourigenesis cell-autonomously, by mediating anchorage-independent cytokinesis via RhoA. In human GSC-derived orthotopic xenografts, EFNB2 knock-down blocked tumour initiation and treatment of established tumours with ephrin-B2-blocking antibodies suppressed progression. Thus, our results indicate that targeting ephrin-B2 may be an effective strategy for the simultaneous inhibition of invasion and proliferation in GBM. DOI: http://dx.doi.org/10.7554/eLife.14845.001 PMID:27350048

  14. Fabrication of Al-TiB2 Nanocomposites by Flux-Assisted Melt Stirring

    NASA Astrophysics Data System (ADS)

    Nabawy, Ahmed M.; Chen, X.-Grant

    2015-08-01

    The fabrication process for Al-TiB2 nanocomposites, in which TiB2 nanoparticles were incorporated into aluminum with K2ZrF6 flux-assisted melt stirring, was studied. The microstructure of the Al-TiB2 nanocomposites was investigated using scanning electron microscopy and transmission electron microscopy. The strengthening effect of TiB2 nanoparticles on the aluminum matrix was examined by microhardness measurements. Results revealed that TiB2 nanoparticles were successfully incorporated and dispersed into the aluminum melt in the presence of the K2ZrF6 flux during mechanical stirring. In the as-cast microstructure, most nanoparticles segregated in the interdendritic regions as a result of particle redistribution during solidification. The addition of 2, 5, and 10 wt pct TiB2 nanoparticles increased the composite hardness by 60, 90, and 150 pct, respectively, when compared to commercial purity aluminum. The role of K2ZrF6 flux agent on the incorporation of nanoparticles into aluminum melt was discussed.

  15. SupraMolecular BioVectors (SMBV) improve antisense inhibition of erbB-2 expression.

    PubMed Central

    Allal, C.; Sixou, S.; Kravtzoff, R.; Soulet, N.; Soula, G.; Favre, G.

    1998-01-01

    New therapeutic strategies are now being developed against adenocarcinoma associated with erbB-2 amplification, particularly by inhibiting p185erbB-2 expression. Antisense oligodeoxynucleotides seem promising for this purpose as long as they are efficiently protected against degradation and targeted into the cells. We present antisense oligonucleotide carriers, the supramolecular biovectors (SMBVs), for which we have already demonstrated the ability to improve both cellular uptake and protection of oligodeoxynucleotide. The present work demonstrates that SMBVs elicit a specific and non-toxic action of antisense compounds in a cell model, irrespective of their sensitivity to nucleases. This is a major point, considering the specificity problems associated with the use of nuclease-resistant phosphorothioate oligodeoxynucleotide. SMBVs improve antisense efficiency of oligodeoxynucleotide designed against p185erbB-2, with a complete growth arrest of SK-Br-3, human adenocarcinoma mammary cells that overexpress p185erbB-2 and no effect on MCF-7 cells that normally express p185erbB-2. The comparison of SMBVs with DOTAP reveals the statistically higher efficiency of SMBVs, which allows the antisense inhibition of p185erbB-2 expression in 65-75% of SK-Br-3 cells (P < 0.05). The efficiency and controlled synthesis of SMBVs underline their potentialities as oligodeoxynucleotide carriers for in vivo experiments. PMID:9652760

  16. Nuclear reactor apparatus

    DOEpatents

    Wade, Elman E.

    1978-01-01

    A lifting, rotating and sealing apparatus for nuclear reactors utilizing rotating plugs above the nuclear reactor core. This apparatus permits rotation of the plugs to provide under the plug refueling of a nuclear core. It also provides a means by which positive top core holddown can be utilized. Both of these operations are accomplished by means of the apparatus lifting the top core holddown structure off the nuclear core while stationary, and maintaining this structure in its elevated position during plug rotation. During both of these operations, the interface between the rotating member and its supporting member is sealingly maintained.

  17. Fast quench reactor method

    DOEpatents

    Detering, Brent A.; Donaldson, Alan D.; Fincke, James R.; Kong, Peter C.; Berry, Ray A.

    1999-01-01

    A fast quench reaction includes a reactor chamber having a high temperature heating means such as a plasma torch at its inlet and a means of rapidly expanding a reactant stream, such as a restrictive convergent-divergent nozzle at its outlet end. Metal halide reactants are injected into the reactor chamber. Reducing gas is added at different stages in the process to form a desired end product and prevent back reactions. The resulting heated gaseous stream is then rapidly cooled by expansion of the gaseous stream.

  18. NEUTRONIC REACTOR SYSTEM

    DOEpatents

    Daniels, F.

    1957-10-15

    Gas-cooled solid-moderator type reactors wherein the fissionable fuel and moderator materials are each in the form of solid pebbles, or discrete particles, and are substantially homogeneously mixed in the proper proportion and placed within the core of the reactor are described. The shape of these discrete particles must be such that voids are present between them when mixed together. Helium enters the bottom of the core and passes through the voids between the fuel and moderator particles to absorb the heat generated by the chain reaction. The hot helium gas is drawn off the top of the core and may be passed through a heat exchanger to produce steam.

  19. THERMAL NUCLEAR REACTOR

    DOEpatents

    Fenning, F.W.; Jackson, R.F.

    1957-09-24

    Nuclear reactors of the graphite moderated air cooled type in which canned slugs or rods of fissile material are employed are discussed. Such a reactor may be provided with a means for detecting dust particles in the exhausted air. The means employed are lengths of dust absorbent cord suspended in vertical holes in the shielding structure above each vertical coolant flow channel to hang in the path of the cooling air issuing from the channels, and associated spindles and drive motors for hauling the cords past detectors, such as Geiger counters, for inspecting the cords periodically. This design also enables detecting the individual channel in which a fault condition may have occurred.

  20. Diagnostics for hybrid reactors

    NASA Astrophysics Data System (ADS)

    Orsitto, Francesco Paolo

    2012-06-01

    The Hybrid Reactor(HR) can be considered an attractive actinide-burner or a fusion assisted transmutation for destruction of transuranic(TRU) nuclear waste. The hybrid reactor has two important subsystems: the tokamak neutron source and the blanket which includes a fuel zone where the TRU are placed and a tritium breeding zone. The diagnostic system for a HR must be as simple and robust as possible to monitor and control the plasma scenario, guarantee the protection of the machine and monitor the transmutation.

  1. Particle bed reactor modeling

    NASA Technical Reports Server (NTRS)

    Sapyta, Joe; Reid, Hank; Walton, Lew

    1993-01-01

    The topics are presented in viewgraph form and include the following: particle bed reactor (PBR) core cross section; PBR bleed cycle; fuel and moderator flow paths; PBR modeling requirements; characteristics of PBR and nuclear thermal propulsion (NTP) modeling; challenges for PBR and NTP modeling; thermal hydraulic computer codes; capabilities for PBR/reactor application; thermal/hydralic codes; limitations; physical correlations; comparison of predicted friction factor and experimental data; frit pressure drop testing; cold frit mask factor; decay heat flow rate; startup transient simulation; and philosophy of systems modeling.

  2. Perspectives on reactor safety

    SciTech Connect

    Haskin, F.E.; Camp, A.L.

    1994-03-01

    The US Nuclear Regulatory Commission (NRC) maintains a technical training center at Chattanooga, Tennessee to provide appropriate training to both new and experienced NRC employees. This document describes a one-week course in reactor, safety concepts. The course consists of five modules: (1) historical perspective; (2) accident sequences; (3) accident progression in the reactor vessel; (4) containment characteristics and design bases; and (5) source terms and offsite consequences. The course text is accompanied by slides and videos during the actual presentation of the course.

  3. Fast quench reactor method

    SciTech Connect

    Detering, B.A.; Donaldson, A.D.; Fincke, J.R.; Kong, P.C.; Berry, R.A.

    1999-08-10

    A fast quench reaction includes a reactor chamber having a high temperature heating means such as a plasma torch at its inlet and a means of rapidly expanding a reactant stream, such as a restrictive convergent-divergent nozzle at its outlet end. Metal halide reactants are injected into the reactor chamber. Reducing gas is added at different stages in the process to form a desired end product and prevent back reactions. The resulting heated gaseous stream is then rapidly cooled by expansion of the gaseous stream. 8 figs.

  4. Diagnostics for hybrid reactors

    SciTech Connect

    Orsitto, Francesco Paolo

    2012-06-19

    The Hybrid Reactor(HR) can be considered an attractive actinide-burner or a fusion assisted transmutation for destruction of transuranic(TRU) nuclear waste. The hybrid reactor has two important subsystems: the tokamak neutron source and the blanket which includes a fuel zone where the TRU are placed and a tritium breeding zone. The diagnostic system for a HR must be as simple and robust as possible to monitor and control the plasma scenario, guarantee the protection of the machine and monitor the transmutation.

  5. Fusion reactor pumped laser

    DOEpatents

    Jassby, Daniel L.

    1988-01-01

    A nuclear pumped laser capable of producing long pulses of very high power laser radiation is provided. A toroidal fusion reactor provides energetic neutrons which are slowed down by a moderator. The moderated neutrons are converted to energetic particles capable of pumping a lasing medium. The lasing medium is housed in an annular cell surrounding the reactor. The cell includes an annular reflecting mirror at the bottom and an annular output window at the top. A neutron reflector is disposed around the cell to reflect escaping neutrons back into the cell. The laser radiation from the annular window is focused onto a beam compactor which generates a single coherent output laser beam.

  6. LINGO-1 regulates oligodendrocyte differentiation by inhibiting ErbB2 translocation and activation in lipid rafts.

    PubMed

    Lee, Xinhua; Shao, Zhaohui; Sheng, Guoqing; Pepinsky, Blake; Mi, Sha

    2014-05-01

    Oligodendrocyte differentiation is negatively regulated by LINGO-1 and positively regulated by the ErbB2 receptor tyrosine kinase. In wild-type oligodendrocytes, inhibition of ErbB2 blocks differentiation, whereas activation of ErbB2 promotes differentiation. In LINGO-1(-/-) oligodendrocytes, inhibition of ErbB2 blocks oligodendrocyte differentiation; whereas activation of ErbB2 does not enhance differentiation. Biological and biochemical evidence showing that LINGO-1 can directly bind to ErbB2, block ErbB2 translocation into lipid rafts, and inhibit its phosphorylation for activation. The study demonstrates a novel regulatory mechanism of ErbB2 function whereby LINGO-1 suppresses oligodendrocyte differentiation by inhibiting ErbB2 translocation and activation in lipid rafts.

  7. Direct Observation of b_2 Vibrational Levels in the ^1B_2 tilde{C} State of SO_2: Precise Measurement of ν_3 Level Staggerings

    NASA Astrophysics Data System (ADS)

    Park, Barratt; Jiang, Jun; Womack, Carrie; Richter, Peter; Field, Robert W.; Whitehill, Andrew Richard; Ono, Shuhei

    2014-06-01

    The ^1B_2 tilde{C} STATE OF SO_2 has been the subject of extensive investigation because it is important in the atmospheric photodissociation of SO_2. The state has a double-minimum potential in the dissociation coordinate, ν_3, arising from vibronic interactions, leading to a staggering of vibrational levels with v_3 odd vs. even. We report the first direct observations of the v_3 fundamental and of other levels with b_2 vibrational symmetry (odd v_3). Our work has made use of LIF, IR-UV double resonance, and coherent MODR techniques. Implications of the precision measurement of v_3 staggerings to the determination of double-minimum potential barrier and to vibronic coupling will be discussed.

  8. Ab initio Computations of the Electronic, Mechanical, and Thermal Properties of Ultra High Temperature Ceramics (UHTC) ZrB2 and HfB2

    NASA Technical Reports Server (NTRS)

    Lawson, John W.; Bauschlicher, Charles W.; Daw, Murray

    2011-01-01

    Refractory materials such as metallic borides, often considered as ultra high temperature ceramics (UHTC), are characterized by high melting point, high hardness, and good chemical inertness. These materials have many applications which require high temperature materials that can operate with no or limited oxidation. Ab initio, first principles methods are the most accurate modeling approaches available and represent a parameter free description of the material based on the quantum mechanical equations. Using these methods, many of the intrinsic properties of these material can be obtained. We performed ab initio calculations based on density functional theory for the UHTC materials ZrB2 and HfB2. Computational results are presented for structural information (lattice constants, bond lengths, etc), electronic structure (bonding motifs, densities of states, band structure, etc), thermal quantities (phonon spectra, phonon densities of states, specific heat), as well as information about point defects such as vacancy and antisite formation energies.

  9. DISSOCIATION OF B2H6 AND ADSORPTION OF THE FRAGMENTS OF B2H6 ON THE STEPPED Ge(100) SURFACE

    NASA Astrophysics Data System (ADS)

    Türkmenoğlu, Mustafa; Katircioğlu, Şenay

    2012-06-01

    In this work, the p-type doping of the SA type stepped Ge(100) surface by a diborane (B2H6) gas flow has been simulated by the possible dissociation and adsorption models. The most probable dissociation model of B2H6 and adsorption models of the fragments of B2H6 on the stepped Ge(100) surface have been determined by the local minimum total energy and/or binding energy calculations based on the Density functional (B3LYP/6-3g) and Hartree-Fock (HF/STO-3g) theories, respectively. The present calculations have shown that, the step region (for both up and down terraces) of the stepped Ge(100) surface has the most attractive sites for BH3 molecules determined to be the first dissociation fragments of B2H6 by an external energy of 1.3 eV. It has been found that, at the first step of the adsorption, BH3 can dissociate to BH2 and BH fragments on the stepped Ge(100) surface. While BH3 and BH2 products prefer to be attached to a single surface Ge atom, BH is bridged between two adjacent surface Ge atoms. According to the present optimization calculations, the p-type doping process of the stepped Ge(100) surface has started with the adsorption of BH3 on the electron deficient site (buckled down) of the Ge dimer bond close to the step edge and ended with the substitutional occupation of the Ge site in the layers of the surface by B atom. The beginning of the p-type doping of the stepped Ge(100) surface has been illustrated by the electronic states of B appeared in the optical energy gap of Ge very close to the edge of the HOMO.

  10. Mechanical properties of ZrB2- and HfB2-based ultra-high temperature ceramics fabricated by spark plasma sintering

    SciTech Connect

    Zapata-Solvas, E.; Jayaseelan, D.; Lin, Hua-Tay; Brown, P.; Lee, W.E.

    2013-01-01

    Flexural strengths at room temperature, at 1400 C in air and at room temperature after 1 h oxidation at 1400 C were determined for ZrB2- and HfB2-based ultra-high temperature ceramics (UHTCs). Defects caused by electrical discharge machining (EDM) lowered measured strengths significantly and were used to calculate fracture toughness via a fracture mechanics approach. ZrB2 with 20 vol.% SiC had room temperature strength of 700 90 MPa, fracture toughness of 6.4 0.6 MPa, Vickers hardness at 9.8 N load of 21.1 0.6 GPa, 1400 C strength of 400 30 MPa and room temperature strength after 1 h oxidation at 1400 C of 678 15 MPa with an oxide layer thickness of 45 5 m. HfB2 with 20 vol.% SiC showed room temperature strength of 620 50 MPa, fracture toughness of 5.0 0.4 MPa, Vickers hardness at 9.8 N load of 27.0 0.6 GPa, 1400 C strength of 590 150 MPa and room temperature strength after 1 h oxidation at 1400 C of 660 25 MPa with an oxide layer thickness of 12 1 m. 2 wt.% La2O3 addition to UHTCs slightly reduced mechanical performance while increasing tolerance to property degradation after oxidation and effectively aided internal stress relaxation during spark plasma sintering (SPS) cooling, as quantified by X-ray diffraction (XRD). Slow crack growth was suggested as the failure mechanism at high temperatures as a consequence of sharp cracks formation during oxidation.

  11. Reactor operation environmental information document

    SciTech Connect

    Haselow, J.S.; Price, V.; Stephenson, D.E.; Bledsoe, H.W.; Looney, B.B.

    1989-12-01

    The Savannah River Site (SRS) produces nuclear materials, primarily plutonium and tritium, to meet the requirements of the Department of Defense. These products have been formed in nuclear reactors that were built during 1950--1955 at the SRS. K, L, and P reactors are three of five reactors that have been used in the past to produce the nuclear materials. All three of these reactors discontinued operation in 1988. Currently, intense efforts are being extended to prepare these three reactors for restart in a manner that protects human health and the environment. To document that restarting the reactors will have minimal impacts to human health and the environment, a three-volume Reactor Operations Environmental Impact Document has been prepared. The document focuses on the impacts of restarting the K, L, and P reactors on both the SRS and surrounding areas. This volume discusses the geology, seismology, and subsurface hydrology. 195 refs., 101 figs., 16 tabs.

  12. Contribution of proton release to the B2 photocurrent of bacteriorhodopsin.

    PubMed

    Misra, S

    1998-07-01

    The contribution of proton release from the so-called proton release group to the microsecond B2 photocurrent from bacteriorhodopsin (bR) oriented in polyacrylamide gels was determined. The fraction of the B2 current due to proton release was resolved by titration of the proton release group in M. At pH values below the pKa of the proton release group in M, the proton release group cannot release its proton during the first half of the bacteriorhodopsin photocycle. At these pH values, the B2 photocurrent is due primarily to translocation of the Schiff base proton to Asp85. The B2 photocurrent was measured in wild-type bR gels at pH 4.5-7.5, in 100 mM KCl/50 mM phosphate. The B2 photocurrent area (proportional to the amount of charge moved) exhibits a pH dependence with a pKa of 6.1. This is suggested to be the pKa of the proton release group in M; the value obtained is in good agreement with previous results obtained by examining photocycle kinetics and pH-sensitive dye signals. In the mutant Glu204Gln, the B2 photocurrent of the mutant membranes was pH independent between pH 4 and 7. Because the proton release group is incapacitated, and early proton release is eliminated in the Glu204Gln mutant, this supports the idea that the pH dependence of the B2 photocurrent in the wild type reflects the titration of the proton release group. In wild-type bacteriorhodopsin, proton release contributes approximately half of the B2 area at pH 7.5. The B2 area in the Glu204Gln mutant is similar to that in the wild type at pH 4.5; in both cases, the B2 current is likely due only to movement of the Schiff base proton to Asp85.

  13. Reactor operation safety information document

    SciTech Connect

    Not Available

    1990-01-01

    The report contains a reactor facility description which includes K, P, and L reactor sites, structures, operating systems, engineered safety systems, support systems, and process and effluent monitoring systems; an accident analysis section which includes cooling system anomalies, radioactive materials releases, and anticipated transients without scram; a summary of onsite doses from design basis accidents; severe accident analysis (reactor core disruption); a description of operating contractor organization and emergency planning; and a summary of reactor safety evolution. (MB)

  14. REACTOR FUEL ELEMENTS TESTING CONTAINER

    DOEpatents

    Whitham, G.K.; Smith, R.R.

    1963-01-15

    This patent shows a method for detecting leaks in jacketed fuel elements. The element is placed in a sealed tank within a nuclear reactor, and, while the reactor operates, the element is sparged with gas. The gas is then led outside the reactor and monitored for radioactive Xe or Kr. (AEC)

  15. EMERGENCY SHUTDOWN FOR NUCLEAR REACTORS

    DOEpatents

    Paget, J.A.; Koutz, S.L.; Stone, R.S.; Stewart, H.B.

    1963-12-24

    An emergency shutdown or scram apparatus for use in a nuclear reactor that includes a neutron absorber suspended from a temperature responsive substance that is selected to fail at a preselected temperature in excess of the normal reactor operating temperature, whereby the neutron absorber is released and allowed to fall under gravity to a preselected position within the reactor core is presented. (AEC)

  16. The First Reactor.

    ERIC Educational Resources Information Center

    Department of Energy, Washington, DC.

    On December 2, 1942, in a racquet court underneath the West Stands of Stagg Field at the University of Chicago, a team of scientists led by Enrico Fermi created the first controlled, self-sustaining nuclear chain reaction. This updated and revised story of the first reactor (or "pile") is based on postwar interviews (as told to Corbin…

  17. NEUTRONIC REACTOR FUEL ELEMENT

    DOEpatents

    Horning, W.A.; Lanning, D.D.; Donahue, D.J.

    1959-10-01

    A fuel slug for a reactor which acts as a safety device is described. The fuel slug is an aluminum tube with a foil lining the inside surface of the tube, the foil being fabricated of uranium in a lead matrix.

  18. NEUTRONIC REACTOR FUEL ELEMENT

    DOEpatents

    Stacy, J.T.

    1958-12-01

    A reactor fuel element having a core of molybdenum-uranium alloy jacketed in stainless steel is described. A barrier layer of tungsten, tantalum, molybdenum, columbium, or silver is interposed between the core and jacket to prevent formation of a low melting eutectic between uranium and the varlous alloy constituents of the stainless steel.

  19. NEUTRONIC REACTOR STRUCTURE

    DOEpatents

    Weinberg, A.M.; Vernon, H.C.

    1961-05-30

    A neutronic reactor is described. It has a core consisting of natural uranium and heavy water and having a K-factor greater than unity which is surrounded by a reflector consisting of natural uranium and ordinary water having a Kfactor less than unity.

  20. JACKETED REACTOR FUEL ELEMENT

    DOEpatents

    Smith, K.F.; Van Thyne, R.J.

    1958-12-01

    A fuel element is described for fast reactors comprised of a core of uranium metal containing material and a jacket around the core, the jacket consisting of from 2.5 to 15 percent of titanium, from 1 to 5 percent of niobium, and from 80 to 96.5 percent of vanadium.

  1. Nuclear reactor installation

    SciTech Connect

    Straub, H.

    1987-09-29

    A nuclear reactor installation is described comprising a pressure vessel having a pair of concentric walls defining a peripheral chamber therebetween; a reactor core disposed within the pressure vessel for heating a primary coolant; a cooling circuit for conveying a secondary coolant in heat exchange relation with the primary coolant. The circuit includes at least one primary heat exchanger within the pressure vessel, at least one secondary heat exchanger outside the pressure vessel, coolant lines extending through the pressure vessel and connecting the heat exchanges together, and circulating means for circulating a secondary coolant through the heat exchangers; a heat sink extending around the pressure vessel; a source of at least one flowable heat-insulating agent outside the pressure vessel; a source of at least one flowable heat-conductive agent outside the pressure vessel; first means communicating the source of heat-insulating agent with the peripheral chamber during normal operation of the reactor core; and second means communicating the source of heat-conductive agent with the peripheral chamber to fill the chamber with heat-conductive agent in response to a disturbance in reactor core cooling.

  2. Plasma core reactor applications

    NASA Technical Reports Server (NTRS)

    Latham, T. S.; Rodgers, R. J.

    1976-01-01

    Analytical and experimental investigations were conducted to demonstrate the feasibility of fissioning uranium plasma core reactors and to characterize space and terrestrial applications for such reactors. Uranium hexafluoride fuel is injected into core cavities and confined away from the surface by argon buffer gas injected tangentially from the peripheral walls. Radiant heat transfer calculations were performed for a six-cavity reactor configuration. Axial working fluid channels are located along a fraction of each cavity peripheral wall. Results of calculations for outward-directed radiant energy fluxes corresponding to radiating temperatures of 2000 to 5000 K indicate total operating pressures from 80 to 650 atm, centerline temperatures from 6900 to 30,000 K, and total radiated powers from 25 to 2500 MW, respectively. Applications are described for this type of reactor such as (1) high-thrust, high specific impulse space propulsion, (2) highly efficient systems for generation of electricity, and (3) hydrogen or synthetic fuel production systems using the intense radiant energy fluxes.

  3. NUCLEAR REACTOR FUEL ELEMENT

    DOEpatents

    Currier, E.L. Jr.; Nicklas, J.H.

    1963-06-11

    A fuel plate is designed for incorporation into control rods of the type utilized in high-flux test reactors. The fuel plate is designed so that the portion nearest the poison section of the control rod contains about one-half as much fissionable material as in the rest of the plate, thereby eliminating dangerous flux peaking in that portion. (AEC)

  4. Nuclear Reactors and Technology

    SciTech Connect

    Cason, D.L.; Hicks, S.C.

    1992-01-01

    This publication Nuclear Reactors and Technology (NRT) announces on a monthly basis the current worldwide information available from the open literature on nuclear reactors and technology, including all aspects of power reactors, components and accessories, fuel elements, control systems, and materials. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database during the past month. Also included are US information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency`s Energy Technology Data Exchange or government-to-government agreements. The digests in NRT and other citations to information on nuclear reactors back to 1948 are available for online searching and retrieval on the Energy Science and Technology Database and Nuclear Science Abstracts (NSA) database. Current information, added daily to the Energy Science and Technology Database, is available to DOE and its contractors through the DOE Integrated Technical Information System. Customized profiles can be developed to provide current information to meet each user`s needs.

  5. Nuclear reactor building

    DOEpatents

    Gou, Perng-Fei; Townsend, Harold E.; Barbanti, Giancarlo

    1994-01-01

    A reactor building for enclosing a nuclear reactor includes a containment vessel having a wetwell disposed therein. The wetwell includes inner and outer walls, a floor, and a roof defining a wetwell pool and a suppression chamber disposed thereabove. The wetwell and containment vessel define a drywell surrounding the reactor. A plurality of vents are disposed in the wetwell pool in flow communication with the drywell for channeling into the wetwell pool steam released in the drywell from the reactor during a LOCA for example, for condensing the steam. A shell is disposed inside the wetwell and extends into the wetwell pool to define a dry gap devoid of wetwell water and disposed in flow communication with the suppression chamber. In a preferred embodiment, the wetwell roof is in the form of a slab disposed on spaced apart support beams which define therebetween an auxiliary chamber. The dry gap, and additionally the auxiliary chamber, provide increased volume to the suppression chamber for improving pressure margin.

  6. Thermal Reactor Safety

    SciTech Connect

    Not Available

    1980-06-01

    Information is presented concerning fire risk and protection; transient thermal-hydraulic analysis and experiments; class 9 accidents and containment; diagnostics and in-service inspection; risk and cost comparison of alternative electric energy sources; fuel behavior and experiments on core cooling in LOCAs; reactor event reporting analysis; equipment qualification; post facts analysis of the TMI-2 accident; and computational methods.

  7. WATER BOILER REACTOR

    DOEpatents

    King, L.D.P.

    1960-11-22

    As its name implies, this reactor utilizes an aqueous solution of a fissionable element salt, and is also conventional in that it contains a heat exchanger cooling coil immersed in the fuel. Its novelty lies in the utilization of a cylindrical reactor vessel to provide a critical region having a large and constant interface with a supernatant vapor region, and the use of a hollow sleeve coolant member suspended from the cover assembly in coaxial relation with the reactor vessel. Cool water is circulated inside this hollow coolant member, and a gap between its outer wall and the reactor vessel is used to carry off radiolytic gases for recombination in an external catalyst chamber. The central passage of the coolant member defines a reflux condenser passage into which the externally recombined gases are returned and condensed. The large and constant interface between fuel solution and vapor region prevents the formation of large bubbles and minimizes the amount of fuel salt carried off by water vapor, thus making possible higher flux densities, specific powers and power densities.

  8. NETL - Chemical Looping Reactor

    SciTech Connect

    2013-07-24

    NETL's Chemical Looping Reactor unit is a high-temperature integrated CLC process with extensive instrumentation to improve computational simulations. A non-reacting test unit is also used to study solids flow at ambient temperature. The CLR unit circulates approximately 1,000 pounds per hour at temperatures around 1,800 degrees Fahrenheit.

  9. Neutronic reactor thermal shield

    DOEpatents

    Wende, Charles W. J.

    1976-06-15

    1. The method of operating a water-cooled neutronic reactor having a graphite moderator which comprises flowing a gaseous mixture of carbon dioxide and helium, in which the helium comprises 40-60 volume percent of the mixture, in contact with the graphite moderator.

  10. NUCLEAR REACTOR COOLANT

    DOEpatents

    Colichman, E.L.

    1959-10-20

    The formation of new reactor coolants which suppress polymerization resulting from pyrolytic and radiation decomposition is described. The coolants consist of polyphenyls and condensed ring compounds having from two to about four carbon rings and from 0.1 to about 5% of beryllium or magnesium dispersed in the hydrocarbon.

  11. NUCLEAR REACTOR COOLANT

    DOEpatents

    Colichman, E.L.

    1959-10-20

    The formation of new reactor coolants which suppress polymerization resulting from pyrolitic and radiation decomposition is described. The coolants consist of polyphenyls and condensed ring compounds having from two to about four carbon rings and from 0.1 to about 10% of an alkall metal dispersed in the hydrocarbon.

  12. Fossil fuel furnace reactor

    DOEpatents

    Parkinson, William J.

    1987-01-01

    A fossil fuel furnace reactor is provided for simulating a continuous processing plant with a batch reactor. An internal reaction vessel contains a batch of shale oil, with the vessel having a relatively thin wall thickness for a heat transfer rate effective to simulate a process temperature history in the selected continuous processing plant. A heater jacket is disposed about the reactor vessel and defines a number of independent controllable temperature zones axially spaced along the reaction vessel. Each temperature zone can be energized to simulate a time-temperature history of process material through the continuous plant. A pressure vessel contains both the heater jacket and the reaction vessel at an operating pressure functionally selected to simulate the continuous processing plant. The process yield from the oil shale may be used as feedback information to software simulating operation of the continuous plant to provide operating parameters, i.e., temperature profiles, ambient atmosphere, operating pressure, material feed rates, etc., for simulation in the batch reactor.

  13. Nuclear reactor building

    DOEpatents

    Gou, P.F.; Townsend, H.E.; Barbanti, G.

    1994-04-05

    A reactor building for enclosing a nuclear reactor includes a containment vessel having a wetwell disposed therein. The wetwell includes inner and outer walls, a floor, and a roof defining a wetwell pool and a suppression chamber disposed there above. The wetwell and containment vessel define a drywell surrounding the reactor. A plurality of vents are disposed in the wetwell pool in flow communication with the drywell for channeling into the wetwell pool steam released in the drywell from the reactor during a LOCA for example, for condensing the steam. A shell is disposed inside the wetwell and extends into the wetwell pool to define a dry gap devoid of wetwell water and disposed in flow communication with the suppression chamber. In a preferred embodiment, the wetwell roof is in the form of a slab disposed on spaced apart support beams which define there between an auxiliary chamber. The dry gap, and additionally the auxiliary chamber, provide increased volume to the suppression chamber for improving pressure margin. 4 figures.

  14. Integral Fast Reactor concept

    SciTech Connect

    Till, C.E.; Chang, Y.I.

    1986-01-01

    The Integral Fast Reactor (IFR) is an innovative LMR concept, being developed at Argonne National Laboratory, that fully exploits the inherent properties of liquid metal cooling and metallic fuel to achieve breakthroughs in economics and inherent safety. This paper describes key features and potential advantages of the IFR concept, technology development status, fuel cycle economics potential, and future development path.

  15. NEUTRONIC REACTOR CONTROL ELEMENT

    DOEpatents

    Beaver, R.J.; Leitten, C.F. Jr.

    1962-04-17

    A boron-10 containing reactor control element wherein the boron-10 is dispersed in a matrix material is describeri. The concentration of boron-10 in the matrix varies transversely across the element from a minimum at the surface to a maximum at the center of the element, prior to exposure to neutrons. (AEC)

  16. REACTOR UNLOADING MEANS

    DOEpatents

    Cooper, C.M.

    1957-08-20

    A means for remotely unloading irradiated fuel slugs from a neutronic reactor core and conveying them to a remote storage tank is reported. The means shown is specifically adapted for use with a reactor core wherein the fuel slugs are slidably held in end to end abutting relationship in the horizontal coolant flow tubes, the slugs being spaced from tae internal walls of the tubes to permit continuous circulation of coolant water therethrough. A remotely operated plunger at the charging ends of the tubes is used to push the slugs through the tubes and out the discharge ends into a special slug valve which transfers the slug to a conveying tube leading into a storage tank. Water under pressure is forced through the conveying tube to circulate around the slug to cool it and also to force the slug through the conveving tube into the storage tank. The slug valve and conveying tube are shielded to prevent amy harmful effects caused by the radioactive slug in its travel from the reactor to the storage tank. With the disclosed apparatus, all the slugs in the reactor core can be conveyed to the storage tank shortly after shutdown by remotely located operating personnel.

  17. Neutronic Reactor Structure

    DOEpatents

    Vernon, H. C.; Weinberg, A. M.

    1961-05-30

    The neutronic reactor is comprised of a core consisting of natural uranium and heavy water with a K-factor greater than unity. The core is surrounded by a reflector consisting of natural uranium and ordinary water with a Kfactor less than unity. (AEC)

  18. NETL - Chemical Looping Reactor

    ScienceCinema

    None

    2016-07-12

    NETL's Chemical Looping Reactor unit is a high-temperature integrated CLC process with extensive instrumentation to improve computational simulations. A non-reacting test unit is also used to study solids flow at ambient temperature. The CLR unit circulates approximately 1,000 pounds per hour at temperatures around 1,800 degrees Fahrenheit.

  19. NEUTRONIC REACTOR FUEL PUMP

    DOEpatents

    Cobb, W.G.

    1959-06-01

    A reactor fuel pump is described which offers long life, low susceptibility to radiation damage, and gaseous fission product removal. An inert-gas lubricated bearing supports a journal on one end of the drive shsft. The other end has an impeller and expansion chamber which effect pumping and gas- liquid separation. (T.R.H.)

  20. MULTISTAGE FLUIDIZED BED REACTOR

    DOEpatents

    Jonke, A.A.; Graae, J.E.A.; Levitz, N.M.

    1959-11-01

    A multistage fluidized bed reactor is described in which each of a number of stages is arranged with respect to an associated baffle so that a fluidizing gas flows upward and a granular solid downward through the stages and baffles, whereas the granular solid stopsflowing downward when the flow of fluidizing gas is shut off.

  1. Stabilized Spheromak Fusion Reactors

    SciTech Connect

    Fowler, T

    2007-04-03

    The U.S. fusion energy program is focused on research with the potential for studying plasmas at thermonuclear temperatures, currently epitomized by the tokamak-based International Thermonuclear Experimental Reactor (ITER) but also continuing exploratory work on other plasma confinement concepts. Among the latter is the spheromak pursued on the SSPX facility at LLNL. Experiments in SSPX using electrostatic current drive by coaxial guns have now demonstrated stable spheromaks with good heat confinement, if the plasma is maintained near a Taylor state, but the anticipated high current amplification by gun injection has not yet been achieved. In future experiments and reactors, creating and maintaining a stable spheromak configuration at high magnetic field strength may require auxiliary current drive using neutral beams or RF power. Here we show that neutral beam current drive soon to be explored on SSPX could yield a compact spheromak reactor with current drive efficiency comparable to that of steady state tokamaks. Thus, while more will be learned about electrostatic current drive in coming months, results already achieved in SSPX could point to a productive parallel development path pursuing auxiliary current drive, consistent with plans to install neutral beams on SSPX in the near future. Among possible outcomes, spheromak research could also yield pulsed fusion reactors at lower capital cost than any fusion concept yet proposed.

  2. Space reactor shielding fabrication

    NASA Technical Reports Server (NTRS)

    Welch, F. H.

    1972-01-01

    The fabrication of space reactor neutron shielding by a melting and casting process utilizing lithium hydride is described. The first neutron shield fabricated is a large pancake shape 86 inches in diameter, containing about 1700 pounds of lithium hydride. This shield, fabricated by the unique melting and casting process, is the largest lithium hydride shield ever built.

  3. NEUTRONIC REACTOR SHIELD

    DOEpatents

    Fermi, E.; Zinn, W.H.

    1957-09-24

    The reactor radiation shield material is comprised of alternate layers of iron-containing material and compressed cellulosic material, such as masonite. The shielding material may be prefabricated in the form of blocks, which can be stacked together in ary desired fashion to form an effective shield.

  4. Fusion reactor materials

    SciTech Connect

    none,

    1989-01-01

    This paper discuses the following topics on fusion reactor materials: irradiation, facilities, test matrices, and experimental methods; dosimetry, damage parameters, and activation calculations; materials engineering and design requirements; fundamental mechanical behavior; radiation effects; development of structural alloys; solid breeding materials; and ceramics.

  5. NEUTRONIC REACTOR CONTROL

    DOEpatents

    Untermyer, S.; Hutter, E.

    1959-08-01

    This patent relates to "shadow" control of a nuclear reactor. The control means comprises a plurality ot elongated rods disposed adjacent and parallel to each other, The morphology and effects of gases generated within sections of neutron absorbing materials and equal length sections of neutron permeable materials together with means for longitudinally pcsitioning the rcds relative to each other.

  6. NRC Targets University Reactors.

    ERIC Educational Resources Information Center

    Marshall, Eliot

    1984-01-01

    The Nuclear Regulatory Commission (NRC) wants universities to convert to low-grade fuel in their research reactions. Researchers claim the conversion, which will bring U.S. reactors in line with a policy the NRC is trying to impress on foreigners, could be financially and scientifically costly. Impact of the policy is considered. (JN)

  7. Reactor component automatic grapple

    DOEpatents

    Greenaway, Paul R.

    1982-01-01

    A grapple for handling nuclear reactor components in a medium such as liquid sodium which, upon proper seating and alignment of the grapple with the component as sensed by a mechanical logic integral to the grapple, automatically seizes the component. The mechanical logic system also precludes seizure in the absence of proper seating and alignment.

  8. Cermet fuel reactors

    SciTech Connect

    Cowan, C.L.; Palmer, R.S.; Van Hoomissen, J.E.; Bhattacharyya, S.K.; Barner, J.O.

    1987-09-01

    Cermet fueled nuclear reactors are attractive candidates for high performance space power systems. The cermet fuel consists of tungsten-urania hexagonal fuel blocks characterized by high strength at elevated temperatures, a high thermal conductivity and resultant high thermal shock resistance. Key features of the cermet fueled reactor design are (1) the ability to achieve very high coolant exit temperatures, and (2) thermal shock resistance during rapid power changes, and (3) two barriers to fission product release - the cermet matrix and the fuel element cladding. Additionally, thre is a potential for achieving a long operating life because of (1) the neutronic insensitivity of the fast-spectrum core to the buildup of fission products and (2) the utilization of a high strength refractory metal matrix and structural materials. These materials also provide resistance against compression forces that potentially might compact and/or reconfigure the core. In addition, the neutronic properties of the refractory materials assure that the reactor remains substantially subcritical under conditions of water immersion. It is concluded that cermet fueled reactors can be utilized to meet the power requirements for a broad range of advanced space applications. 4 refs., 4 figs., 3 tabs.

  9. ErbB2-dependent chemotaxis requires microtubule capture and stabilization coordinated by distinct signaling pathways.

    PubMed

    Benseddik, Khedidja; Sen Nkwe, Nadine; Daou, Pascale; Verdier-Pinard, Pascal; Badache, Ali

    2013-01-01

    Activation of the ErbB2 receptor tyrosine kinase stimulates breast cancer cell migration. Cell migration is a complex process that requires the synchronized reorganization of numerous subcellular structures including cell-to-matrix adhesions, the actin cytoskeleton and microtubules. How the multiple signaling pathways triggered by ErbB2 coordinate, in time and space, the various processes involved in cell motility, is poorly defined. We investigated the mechanism whereby ErbB2 controls microtubules and chemotaxis. We report that activation of ErbB2 increased both cell velocity and directed migration. Impairment of the Cdc42 and RhoA GTPases, but not of Rac1, prevented the chemotactic response. RhoA is a key component of the Memo/ACF7 pathway whereby ErbB2 controls microtubule capture at the leading edge. Upon Memo or ACF7 depletion, microtubules failed to reach the leading edge and cells lost their ability to follow the chemotactic gradient. Constitutive ACF7 targeting to the membrane in Memo-depleted cells reestablished directed migration. ErbB2-mediated activation of phospholipase C gamma (PLCγ) also contributed to cell guidance. We further showed that PLCγ signaling, via classical protein kinases C, and Memo signaling converged towards a single pathway controlling the microtubule capture complex. Finally, inhibiting the PI3K/Akt pathway did not affect microtubule capture, but disturbed microtubule stability, which also resulted in defective chemotaxis. PI3K/Akt-dependent stabilization of microtubules involved repression of GSK3 activity on the one hand and inhibition of the microtubule destabilizing protein, Stathmin, on the other hand. Thus, ErbB2 triggers distinct and complementary pathways that tightly coordinate microtubule capture and microtubule stability to control chemotaxis.

  10. A new scaling relation for n-AlN doped superconducting MgB2

    NASA Astrophysics Data System (ADS)

    Tripathi, D.; Dey, T. K.

    2013-09-01

    The scaling behavior of nano-aluminum nitride added polycrystalline MgB2 superconductor is discussed. A series of polycrystalline MgB2 samples with different amounts of nanosized AlN addition are synthesized by solid reaction. All the synthesized pellets are subjected to x-ray diffraction, field emission gun scanning electron microscopy (FEG-SEM), and transmission electron microscopy (TEM) to examine their micro-structural features. A marginal decrease in lattice parameters of pure MgB2 with AlN nanoparticles addition is observed. Surface morphology reveals randomly oriented hexagonal MgB2 grains decorated with AlN nanoparticles between the grain boundaries and also scattered on the grain surface. For higher concentration, n-AlN agglomerates are visible. Resistivity data confirm a decrease in superconducting transition temperature (Tc) from 38.5 to 37 K and increase in transition width (ΔTc) with increased loading of n-AlN in MgB2. The critical current density (Jc) of the pellets at 4, 10, 20, and 30 K is evaluated from the magnetization data between ±6 T and is explained well in the framework of collective pinning model. The normalized pinning force density of n-AlN doped MgB2 at various temperatures indicates an excellent scaling with respect to Hn (the field corresponding to which Fp drops to half of its maximum value) as the scaling field. A new scaling expression derived, using the expression of field dependence of Jc proposed by "collective pinning model" in small bundle regime, demonstrates an excellent agreement with the measured normalized pinning force density (viz., Fp/Fpmax vs. hn) of the AlN nanoparticles doped MgB2 superconductors.

  11. Alternative approaches to fusion. [reactor design and reactor physics for Tokamak fusion reactors

    NASA Technical Reports Server (NTRS)

    Roth, R. J.

    1976-01-01

    The limitations of the Tokamak fusion reactor concept are discussed and various other fusion reactor concepts are considered that employ the containment of thermonuclear plasmas by magnetic fields (i.e., stellarators). Progress made in the containment of plasmas in toroidal devices is reported. Reactor design concepts are illustrated. The possibility of using fusion reactors as a power source in interplanetary space travel and electric power plants is briefly examined.

  12. TOPICAL REVIEW: The widely variable resistivity of MgB2 samples

    NASA Astrophysics Data System (ADS)

    Rowell, John M.

    2003-06-01

    In this brief review, I consider a rather mundane property of MgB2, namely its resistivity as a function of temperature. It turns out that a comparison of resistivity data for a wide variety of samples, from single crystals to films, wires and polycrystalline bulk, is surprisingly informative. The majority of samples of MgB2 exhibit resistivities that are much higher than the low values that are seen in a relatively small number of single crystals, bulk samples and films. In many cases, the resistivity is increased over the single crystal values by orders of magnitude. Even at these high values, there is often still a metallic temperature dependence of the resistivity, and surprisingly, Tc is often at or near the bulk value of 39 K. The resistivity increase has been ascribed to a reduction in the effective current-carrying cross-sectional area of the sample. If this loss of cross-sectional area is the dominant factor contributing to the increase in resistivity of MgB2 samples, then the critical current density must be decreased by the same loss in the effective area. Comparisons of the MgB2 resistivity with the properties of disordered 'cluster compound' superconductors, of HTS materials and of granular Al (heavily contaminated with oxygen), show similarities between the MgB2 behaviour and the results of the HTS and Al studies. I discuss various effects that might contribute to the reduction in effective sample area in MgB2 samples, to the increase in resistivity and to a reduction in Jc. I speculate that a Josephson junction model of the grain boundaries in MgB2 might apply to samples with extremely high resistivities. Alternatively, it has been suggested that the two-band nature of MgB2 can result in an unusual behaviour of its resistivity and Tc as the material changes from the 'clean' to 'dirty' limits. I conclude that measurements of both the resistivity and the transport critical current density in a wide variety of bulk and film samples would be very useful

  13. The phase analysis of spark plasma sintered MgB2 after ball milling.

    PubMed

    Kang, Deuk-Kyun; Kim, Dong-Woong; Kim, Cheol-Jin; Ahn, In-Shup

    2010-01-01

    Mg and amorphous B powders below 10 and 3 micro meter were used as raw materials, and mixed by planetary-mill for 9 hours at argon atmosphere. MgB2 bulk was fabricated at the various temperatures by Spark Plasma Sintering. In the sintering process, mixed powders were sintered in graphite mold, at the pressure of 55 Mpa. The fabricated MgB2 samples were evaluated with XRD, EDS, FE-SEM, PPMS. MgB2, MgO and Fe phases were observed from XRD result. In the results, MgO and Fe were impurity which may affect superconducting properties of MgB2 samples, and it's distribution could be confirmed from EDS mapping result. In order to confirm the formation of MgB2 phase, DTA was used as heating rate of 10 degrees C/min at Ar atmosphere from room temperature to 1200 degrees C. In the PPMS result, the Tc (critical temperature) was about 21 K, and the density of spark plasma sintered samples increased to 1.87 g/cm3 by increasing sintering temperature.

  14. Hexagonal OsB2 reduction upon heating in H2 containing environment

    DOE PAGES

    Xie, Zhilin; Blair, Richard G.; Orlovskaya, Nina; ...

    2014-10-23

    The stability of hexagonal ReB2 type OsB2 powder upon heating under reforming gas was investigated. Pure Os metal particles were detected by powder X-ray diffraction starting at 375⁰ C and complete transformation of OsB2 to metallic Os was observed at 725⁰ C. The mechanisms of precipitation of metallic Os is proposed and changes in the lattice parameters of OsB2 upon heating are analysed in terms of the presence of oxygen or water vapour in the heating chamber. Previous studies suggested that Os atoms possess (0) valence, while B atoms possess both (+3) and ( 3) valences in the alternating boron/osmiummore » sheet structure of hexagonal (P63/mmc, No. 194) OsB2; if controllable method for Os removal from the lattice could be found, the opportunity would arise to form two-dimensional (2D) layers consisting of pure B atoms.« less

  15. Infralimbic EphB2 Modulates Fear Extinction in Adolescent Rats

    PubMed Central

    Cruz, Emmanuel; Soler-Cedeño, Omar; Negrón, Geovanny; Criado-Marrero, Marangelie; Chompré, Gladys

    2015-01-01

    Adolescent rats are prone to impaired fear extinction, suggesting that mechanistic differences in extinction could exist in adolescent and adult rats. Since the infralimbic cortex (IL) is critical for fear extinction, we used PCR array technology to identify gene expression changes in IL induced by fear extinction in adolescent rats. Interestingly, the ephrin type B receptor 2 (EphB2), a tyrosine kinase receptor associated with synaptic development, was downregulated in IL after fear extinction. Consistent with the PCR array results, EphB2 levels of mRNA and protein were reduced in IL after fear extinction compared with fear conditioning, suggesting that EphB2 signaling in IL regulates fear extinction memory in adolescents. Finally, reducing EphB2 synthesis in IL with shRNA accelerated fear extinction learning in adolescent rats, but not in adult rats. These findings identify EphB2 in IL as a key regulator of fear extinction during adolescence, perhaps due to the increase in synaptic remodeling occurring during this developmental phase. PMID:26354908

  16. Effects of Metal Powder Addition in Ni-Sheathed PIT MgB2 Tapes

    NASA Astrophysics Data System (ADS)

    Tachikawa, K.; Yamada, Y.; Katagiri, K.; Kumakura, H.; Iwamoto, A.; Watanabe, K.

    2004-06-01

    The effect of different metal powder additions on the transport current and stress/strain performance of ex-situ processed MgB2 tapes with Ni sheath has been studied. The metal powder added to the core exhibits elongated morphology after the fabrication. The addition of low melting point metal powder, e.g. In and Sn, produces an appreciable increase in the Jc of MgB2 core. An addition of 10 vol% In enhances Jc by a factor of 6 to 7 after the combination of rolling and annealing at 200 °C, up to the order of 105 A/cm2 at 0.5 T and 4.2 K. An addition of 10 vol% Sn enhances Jc by a factor of ˜ 3. The In and Sn additions also appreciably increase the n-value of the current-voltage transition. Both In and Sn metals infiltrate into gaps between MgB2 grains, improving the linkage of the grains. Current may transfer through the impregnated metal by the proximity effect. Furthermore, the metal powder addition appreciably improves the strain tolerance in MgB2 tapes. The low melting point metal powder addition is a relatively simple and easy approach to yield better transport current and stress/strain performance in ex-situ MgB2 tapes.

  17. EphrinB2 repression through ZEB2 mediates tumour invasion and anti-angiogenic resistance

    PubMed Central

    Depner, C.; zum Buttel, H.; Böğürcü, N.; Cuesta, A. M.; Aburto, M. R.; Seidel, S.; Finkelmeier, F.; Foss, F.; Hofmann, J.; Kaulich, K.; Barbus, S.; Segarra, M.; Reifenberger, G.; Garvalov, B. K.; Acker, T.; Acker-Palmer, A.

    2016-01-01

    Diffuse invasion of the surrounding brain parenchyma is a major obstacle in the treatment of gliomas with various therapeutics, including anti-angiogenic agents. Here we identify the epi-/genetic and microenvironmental downregulation of ephrinB2 as a crucial step that promotes tumour invasion by abrogation of repulsive signals. We demonstrate that ephrinB2 is downregulated in human gliomas as a consequence of promoter hypermethylation and gene deletion. Consistently, genetic deletion of ephrinB2 in a murine high-grade glioma model increases invasion. Importantly, ephrinB2 gene silencing is complemented by a hypoxia-induced transcriptional repression. Mechanistically, hypoxia-inducible factor (HIF)-1α induces the EMT repressor ZEB2, which directly downregulates ephrinB2 through promoter binding to enhance tumour invasiveness. This mechanism is activated following anti-angiogenic treatment of gliomas and is efficiently blocked by disrupting ZEB2 activity. Taken together, our results identify ZEB2 as an attractive therapeutic target to inhibit tumour invasion and counteract tumour resistance mechanisms induced by anti-angiogenic treatment strategies. PMID:27470974

  18. Mechanical Properties of In-Situ FeAl-TiB2 Intermetallic Matrix Composites

    NASA Astrophysics Data System (ADS)

    Kim, Jonghoon; Park, Bonggyu; Park, Yongho; Park, Ikmin; Lee, Heesoo

    Intermetallic matrix composites reinforced with ceramic particles have received a great deal of attention. Iron aluminide is known to be a good material for the matrix in such composites. Two processes were used to fabricate FeAl-TiB2 intermetallic matrix composites. One was liquid melt in-situ mixing, and the other was arc melting and suction casting processes. FeAl-TiB2 IMCs obtained by two different methods were investigated to elucidate the influence of TiB2 content. In both methods, the grain size in the FeAl alloy decreased with the presence of titanium diboride. The grain size of in-situ FeAl-TiB2 IMCs became smaller than that of arc FeAl-TiB2 IMCs. Significant increase in fracture stress and hardness was achieved in the composites. The in-situ process gives clean, contamination-free matrix/reinforcement interface which maintained good bonding causing high load bearing capability. This contributed to the increase in the mechanical properties of composites.

  19. Critical current density and grain connectivity of Bi-2223 added MgB2 superconductor

    NASA Astrophysics Data System (ADS)

    Tripathi, D.; Dey, T. K.

    2014-04-01

    Polycrystalline MgB2 with addition of 0, 1, 3, and 5 wt. % of Bi-2223(Bi1.8Pb0.26Sr2Ca2Cu3O10+x) powder has been synthesized by solid reaction process. The effect of Bi-2223 addition on current transport and superconducting properties of polycrystalline MgB2 superconductor is discussed. Four probe DC resistivity measurement shows that low level of Bi-2223 addition hardly affects the superconducting transition temperature, Tc of MgB2. The modified Bloch- Gruneisen (B-G) analysis of normal state resistivity data reveals a decrease in intergrain connectivity and increase in intragrain connectivity of MgB2 by Bi-2223 addition. The critical current density of present set of samples is estimated from M- H hysteresis loop in the light of Bean's model. MgB2 added with 1 wt. % of Bi- 2223 added gives the best performance (˜ 2 times enhancement in Jc) amongst the studied samples.

  20. Abbreviated New Drug Applications and 505(b)(2) Applications. Final rule.

    PubMed

    2016-10-06

    The Food and Drug Administration (FDA, the Agency, or we) is issuing a final rule to implement Title XI of the Medicare Prescription Drug, Improvement, and Modernization Act of 2003 (MMA), which amended provisions of the Federal Food, Drug, and Cosmetic Act (the FD&C Act) that govern the approval of 505(b)(2) applications and abbreviated new drug applications (ANDAs). This final rule implements portions of Title XI of the MMA that pertain to provision of notice to each patent owner and the new drug application (NDA) holder of certain patent certifications made by applicants submitting 505(b)(2) applications or ANDAs; the availability of 30-month stays of approval on 505(b)(2) applications and ANDAs that are otherwise ready to be approved; submission of amendments and supplements to 505(b)(2) applications and ANDAs; and the types of bioavailability and bioequivalence data that can be used to support these applications. This final rule also amends certain regulations regarding 505(b)(2) applications and ANDAs to facilitate compliance with and efficient enforcement of the FD&C Act.