Sample records for liquid-iron outer core

  1. Experimental partitioning of uranium between liquid iron sulfide and liquid silicate: Implications for radioactivity in the Earth's core

    E-Print Network [OSTI]

    Minarik, William

    Experimental partitioning of uranium between liquid iron sulfide and liquid silicate: Implications Measurable uranium (U) is found in metal sulfide liquids in equilibrium with molten silicate at conditions shows that K is depleted in the Earth by $50%, while U and Th are slightly enriched (Palme and O

  2. Uranium partitioning between liquid iron and silicate melt at high pressures: implications for uranium solubility in planetary cores

    E-Print Network [OSTI]

    Xuezhao Bao; Richard A. Secco; Joel E. Gagnon; Brian J. Fryer

    2006-06-29T23:59:59.000Z

    We have investigated the partitioning of U between silicate melt and Fe liquid at pressures of 3.0 to14.5 GPa and temperatures of 1660 to 2500 oC. The solubility of U in liquid Fe is in the range of 0.6 to 800 ppm and increases with temperature (T) and pressure (P). When P = or > 7 GPa and T > Tmelt of the silicate phase (olivine), the U concentration in Fe is 3 to 5 times greater than for run products where T Tmelt of the silicate phase), then > 2.4 ppb U could have entered the core. Alternatively, if a core with same composition formed by percolation (T Uranium; partition coefficients; high pressure; dynamos; planetary cores; heat sources, LA-ICP-MS.

  3. Faraday Discuss., 1997, 106, 205217 First principles calculations on crystalline and liquid iron at

    E-Print Network [OSTI]

    Vocadlo, Lidunka

    Hauptstrasse 8-10/136, A-1040 V ienna, Austria Ab initio electronic structure calculations, based upon density on liquid iron and we present the Ðrst ab initio quantum molecular dynamics calculations on the structure and transport properties of liquid iron under core conditions. Our calculations show that the structure

  4. Title of dissertation: LIQUID SODIUM MODEL OF EARTH'S OUTER CORE Woodrow Shew, Doctor of Philosophy, 2004

    E-Print Network [OSTI]

    Lathrop, Daniel P.

    motions (i.e. the energy injection scale for the underlying fluid motion). We observe a sensitive a knee in the energy spectrum of outer core fluid motions associated with convective length and time for the following things: Nate boxed wine, boxing, poker, golf, mad editing skills Colin general rabblerousing Matt

  5. Transitions between turbulent and laminar superfluid vorticity states in the outer core of a neutron star

    E-Print Network [OSTI]

    C. Peralta; A. Melatos; M. Giacobello; A. Ooi

    2006-07-08T23:59:59.000Z

    We investigate the global transition from a turbulent state of superfluid vorticity to a laminar state, and vice versa, in the outer core of a neutron star. By solving numerically the hydrodynamic Hall-Vinen-Bekarevich-Khalatnikov equations for a rotating superfluid in a differentially rotating spherical shell, we find that the meridional counterflow driven by Ekman pumping exceeds the Donnelly-Glaberson threshold throughout most of the outer core, exciting unstable Kelvin waves which disrupt the rectilinear vortex array, creating a vortex tangle. In the turbulent state, the torque exerted on the crust oscillates, and the crust-core coupling is weaker than in the laminar state. This leads to a new scenario for the rotational glitches observed in radio pulsars: a vortex tangle is sustained in the differentially rotating outer core by the meridional counterflow, a sudden spin-up event brings the crust and core into corotation, the vortex tangle relaxes back to a rectilinear vortex array, then the crust spins down electromagnetically until enough meridional counterflow builds up to reform a vortex tangle. The turbulent-laminar transition can occur uniformly or in patches; the associated time-scales are estimated from vortex filament theory. We calculate numerically the global structure of the flow with and without an inviscid superfluid component, for Hall-Vinen and Gorter-Mellink forms of the mutual friction. We also calculate the post-glitch evolution of the angular velocity of the crust and its time derivative, and compare the results with radio pulse timing data, predicting a correlation between glitch activity and Reynolds number.

  6. MHD evolution of a fragment of a CME core in the outer solar corona

    E-Print Network [OSTI]

    P. Pagano; F. Reale; S. Orlando; G. Peres

    2007-01-05T23:59:59.000Z

    Detailed hydrodynamic modeling explained several features of a fragment of the core of a Coronal Mass Ejection observed with SoHO/UVCS at 1.7 Ro on 12 December 1997, but some questions remained unsolved. We investigate the role of the magnetic fields in the thermal insulation and the expansion of an ejected fragment (cloud) traveling upwards in the outer corona. We perform MHD simulations including the effects of thermal conduction and radiative losses of a dense spherical or cylindrical cloud launched upwards in the outer corona, with various assumptions on the strength and topology of the ambient magnetic field; we also consider the case of a cylindrical cloud with an internal magnetic field component along its axis. We find that a weak ambient magnetic field (beta~20) with open topology provides both significant thermal insulation and large expansion. The cylindrical cloud expands more than the spherical one.

  7. Core-level satellites and outer core-level multiplet splitting in Mn model compounds

    SciTech Connect (OSTI)

    Nelson, A. J. [Lawrence Livermore National Laboratory, University of California, Livermore, California 94550 (United States)] [Lawrence Livermore National Laboratory, University of California, Livermore, California 94550 (United States); Reynolds, John G. [Lawrence Livermore National Laboratory, University of California, Livermore, California 94550 (United States)] [Lawrence Livermore National Laboratory, University of California, Livermore, California 94550 (United States); Roos, Joseph W. [Ethyl Corporation, Richmond, Virginia 23217 (United States)] [Ethyl Corporation, Richmond, Virginia 23217 (United States)

    2000-07-01T23:59:59.000Z

    We report a systematic study of the Mn 2p, 3s, and 3p core-level photoemission and satellite structures for Mn model compounds. Charge transfer from the ligand state to the 3d metal state is observed and is distinguished by prominent shake-up satellites. We also observe that the Mn 3s multiplet splitting becomes smaller as the Mn oxidation state increases, and that 3s-3d electron correlation reduces the branching ratio of the {sup 7}S:{sup 5}S states in the Mn 3s spectra. In addition, as the ligand electronegativity decreases, the spin-state purity is lost in the 3s spectra, as evidenced by peak broadening. Our results are best understood in terms of the configuration-interaction model including intrashell electron correlation, charge transfer, and final-state screening. (c) 2000 American Vacuum Society.

  8. A Modification of the Inner and Outer Core for Reactor Pressure Vessel Lifetime Extension

    SciTech Connect (OSTI)

    Seo, Bo Kyun [Hanyang University (Korea, Republic of); Kim, Jong Kyung [Hanyang University (Korea, Republic of); Shin, Chang Ho [Hanyang University (Korea, Republic of); Kwon, Tae Je [Nuclear Fuel Company (Korea, Republic of)

    2001-03-15T23:59:59.000Z

    The feasibility of nuclear power plant lifetime extension was examined by reducing the fast neutron fluence at the reactor pressure vessel (RPV) and relieving irradiation embrittlement of materials, and thus ensuring enough structural integrity beyond the design lifetime. Two fluence reduction options, peripheral assembly replacement and additional shield installation in the outer core structures, were applied to the Kori Unit-1 reactor, and the fluence reduction effect was carefully analyzed. For an accurate estimate of the neutron fluence at the RPV and a reasonable description of the modified peripheral assemblies, a full-scope explicit modeling of a Monte Carlo simulation was employed in all calculations throughout this study. The Kori Unit-1 cycle-16 core was modeled on a three-dimensional representation by using the MCNP4B code, and the fluence distribution was estimated at the inner wall beltline around the circumferential weld of the RPV. On the basis of fracture toughness requirements of the RPV, the two modified cases were predicted to have an additional life of 7 to 10 effective full-power years. Throughout the core nuclear characteristics analyses, it was confirmed that the critical peaking factors for safe reactor operation were satisfied with the design limits.

  9. SOHO, the Solar and Heliospheric Observatory, is a project of international cooperation between ESA and NASA to study the Sun, from its deep core to the outer

    E-Print Network [OSTI]

    cooperation between ESA and NASA to study the Sun, from its deep core to the outer corona, and the solar wind and dynamics of the solar interior? · Why does the solar corona exist and how is it heated to the extremely

  10. Distribution of U and Th and Their Nuclear Fission in the Outer Core of the Earth and Their effects on the Geodynamics

    E-Print Network [OSTI]

    Bao, Xuezhao

    2009-01-01T23:59:59.000Z

    Here we propose that there is a lot of heat producing elements U and Th in the outer core of the Earth. The heat released from them is the major energy source for driving the material movement within the interior of Earth, including plate motion. According to seismic tomography, the hottest area is the mantle under the central Pacific Ocean. Combined with geomagnetic data, it is derived that the magnetic and heat convection centers deviate from the geographic center to the Pacific direction for 400 km. Therefore, U and Th are more concentrated in a position close to the equator in the lower outer core under the central Pacific Ocean, and have formed a large U, Th-rich center there. Another small U, Th-rich center is located in a position close to the equator in the lower outer core under Africa, which is directly opposite of the large U, Th-rich center past the solid inner core. The two U, Th-rich centers may have led to the formation of the Pacific and Africa super-plumes and are offering energy to run the p...

  11. Iron under Earth's core conditions: Liquid-state thermodynamics and high-pressure melting curve from ab initio calculations

    E-Print Network [OSTI]

    Alfè, Dario

    Hugoniot curves cross the melting line, and the sound speed and Gru¨neisen parameter along the HugoniotIron under Earth's core conditions: Liquid-state thermodynamics and high-pressure melting curve-augmented-wave implementation are used to calculate the free energy and a range of other thermodynamic properties of liquid iron

  12. Material with core-shell structure

    DOE Patents [OSTI]

    Luhrs, Claudia (Rio Rancho, NM); Richard, Monique N. (Ann Arbor, MI); Dehne, Aaron (Maumee, OH); Phillips, Jonathan (Rio Rancho, NM); Stamm, Kimber L. (Ann Arbor, MI); Fanson, Paul T. (Brighton, MI)

    2011-11-15T23:59:59.000Z

    Disclosed is a material having a composite particle, the composite particle including an outer shell and a core. The core is made from a lithium alloying material and the outer shell has an inner volume that is greater in size than the core of the lithium alloying material. In some instances, the outer mean diameter of the outer shell is less than 500 nanometers and the core occupies between 5 and 99% of the inner volume. In addition, the outer shell can have an average wall thickness of less than 100 nanometers.

  13. Electromagnetic pump stator core

    DOE Patents [OSTI]

    Fanning, Alan W. (San Jose, CA); Olich, Eugene E. (Aptos, CA); Dahl, Leslie R. (Livermore, CA)

    1995-01-01T23:59:59.000Z

    A stator core for supporting an electrical coil includes a plurality of groups of circumferentially abutting flat laminations which collectively form a bore and perimeter. A plurality of wedges are interposed between the groups, with each wedge having an inner edge and a thicker outer edge. The wedge outer edges abut adjacent ones of the groups to provide a continuous path around the perimeter.

  14. JOURNAL DE PHYSIQUE Colloque C2, supplkment au n " 3, Tome 40, mars 1979,page C2-632 A?PLICATIilN OF MOSSBAUER SPECTF!OSC3?Y TO DEOXIDATION FROM LIQUID IRON BY ALUMINIUM

    E-Print Network [OSTI]

    Boyer, Edmond

    , because electrons of iron species leaned around aluminium species in Fe-A1 alloy. I. Introduction?PLICATIilN OF MOSSBAUER SPECTF!OSC3?Y TO DEOXIDATION FROM LIQUID IRON BY ALUMINIUM S. Watanabe, A. ~hkawa*,Y. Kaneko and Y liquide par l'aluminium. L'hercy- nite FeAl 0 et les formes y, K, 8 et or de A1203 sont les formes d

  15. Electromagnetic pump stator core

    DOE Patents [OSTI]

    Fanning, A.W.; Olich, E.E.; Dahl, L.R.

    1995-01-17T23:59:59.000Z

    A stator core for supporting an electrical coil includes a plurality of groups of circumferentially abutting flat laminations which collectively form a bore and perimeter. A plurality of wedges are interposed between the groups, with each wedge having an inner edge and a thicker outer edge. The wedge outer edges abut adjacent ones of the groups to provide a continuous path around the perimeter. 21 figures.

  16. Laminated electromagnetic pump stator core

    DOE Patents [OSTI]

    Fanning, A.W.

    1995-08-08T23:59:59.000Z

    A stator core for an electromagnetic pump includes a plurality of circumferentially abutting tapered laminations extending radially outwardly from a centerline axis to collectively define a radially inner bore and a radially outer circumference. Each of the laminations includes radially inner and outer edges and has a thickness increasing from the inner edge toward the outer edge to provide a substantially continuous path adjacent the circumference. This pump is used in nuclear fission reactors. 19 figs.

  17. 4/3/12 2:13 PMMantle Convection: Earth's Interior Page 1 of 3http://conman.geos.vt.edu/~sdk/mantle/interior.html

    E-Print Network [OSTI]

    Smith-Konter, Bridget

    spherical shells: the crust, the mantle, and the core. The crust ranges from 6 to 70 kilometers thick minerals and the liquid iron outer core. #12;4/3/12 2:13 PMMantle Convection: Earth's Interior Page 2 of 3, O) in the Sun's outer corona and show no indication of chemical alteration since their formation

  18. Turbine airfoil with outer wall thickness indicators

    DOE Patents [OSTI]

    Marra, John J; James, Allister W; Merrill, Gary B

    2013-08-06T23:59:59.000Z

    A turbine airfoil usable in a turbine engine and including a depth indicator for determining outer wall blade thickness. The airfoil may include an outer wall having a plurality of grooves in the outer surface of the outer wall. The grooves may have a depth that represents a desired outer surface and wall thickness of the outer wall. The material forming an outer surface of the outer wall may be removed to be flush with an innermost point in each groove, thereby reducing the wall thickness and increasing efficiency. The plurality of grooves may be positioned in a radially outer region of the airfoil proximate to the tip.

  19. Turbine airfoil with a compliant outer wall

    DOE Patents [OSTI]

    Campbell, Christian X. (Oviedo, FL); Morrison, Jay A. (Oviedo, FL)

    2012-04-03T23:59:59.000Z

    A turbine airfoil usable in a turbine engine with a cooling system and a compliant dual wall configuration configured to enable thermal expansion between inner and outer layers while eliminating stress formation in the outer layer is disclosed. The compliant dual wall configuration may be formed a dual wall formed from inner and outer layers separated by a support structure. The outer layer may be a compliant layer configured such that the outer layer may thermally expand and thereby reduce the stress within the outer layer. The outer layer may be formed from a nonplanar surface configured to thermally expand. In another embodiment, the outer layer may be planar and include a plurality of slots enabling unrestricted thermal expansion in a direction aligned with the outer layer.

  20. Banded electromagnetic stator core

    DOE Patents [OSTI]

    Fanning, A.W.; Gonzales, A.A.; Patel, M.R.; Olich, E.E.

    1994-04-05T23:59:59.000Z

    A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups. 5 figures.

  1. Banded electromagnetic stator core

    DOE Patents [OSTI]

    Fanning, A.W.; Gonzales, A.A.; Patel, M.R.; Olich, E.E.

    1996-06-11T23:59:59.000Z

    A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups. 5 figs.

  2. DI in the outer Galaxy

    E-Print Network [OSTI]

    Jayaram N. Chengalur; Robert Braun; W. Butler Burton

    1997-01-13T23:59:59.000Z

    We report on a deep search with the Westerbork Synthesis Radio Telescope towards the galactic anticenter for the 327 MHz hyperfine transition of DI. This is a favorable direction for a search because: (i) the HI optical depth is high due to velocity crowding; (ii) the observed molecular column density is low (implying that most of the deuterium would probably be in atomic form, rather than in HD); and (iii) the stellar reprocessing should be minimal. Our observations are about a factor of two more sensitive than previous searches for DI in this direction. We detect a low significance (about 4 sigma) feature, consistent in both amplitude and center frequency with an emission feature reported previously (Blitz & Heiles 1987). If this is the DI line, then the implied N_D/N_H of 3.9+/-1.0 x 10^-5 is comparable to the inferred pre-solar deuterium abundance. Our observation is consistent with the recent low measurements of D/H towards high-redshift Lyman-limit systems. On the other hand, if the reports of high DI abundance (about 24 x 10^-5) in such systems are confirmed, then our observations imply that even in regions of reduced star formation within the outer Galaxy, the DI abundance has been reduced by a factor of about 6 from the primordial abundance.

  3. CONCURRENCY AND COMPUTATION: PRACTICE AND EXPERIENCE Concurrency Computat.: Pract. Exper. 1; 1:1 Prepared using cpeauth.cls [Version: 2002/09/19 v2.02

    E-Print Network [OSTI]

    Jimack, Peter

    numerical calculations. For asymptotically large problems the spherical transform is shown conducting fluid (liquid iron plus a small percentage of lighter elements) confined to the outer core, a 2260 km thick spherical shell some 2800 km below Earth's surface. In this dynamo process, movement

  4. Thermal metastabilities in the solar core

    E-Print Network [OSTI]

    Attila Grandpierre; Gabor Agoston

    2002-01-18T23:59:59.000Z

    Linear stability analysis indicates that solar core is thermally stable for infinitesimal internal perturbations. For the first time, thermal metastabilities are found in the solar core when outer perturbations with significant amplitude are present. The obtained results show that hot bubbles generated by outer perturbations may travel a significant distance in the body of the Sun. These deep-origin hot bubbles have mass, energy, and chemical composition that may be related to solar flares. The results obtained may have remarkable relations to activity cycles in planets like Jupiter and also in extrasolar planetary systems.

  5. Beyond the Active Site: The Impact of the Outer Coordination...

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

    the Active Site: The Impact of the Outer Coordination Sphere on Electrocatalysts for Hydrogen Production and Oxidation. Beyond the Active Site: The Impact of the Outer Coordination...

  6. Core Specialization

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

    cores per node for handling system services, and thus reduce the effects of timing jitter due to interruptions from the operating system at the expense of (possibly) requiring...

  7. A new method of coating oilfield core for laboratory studies

    SciTech Connect (OSTI)

    Menzie, D.E.; Dutta, S.; Shadizadeh, R.S.

    1988-05-01T23:59:59.000Z

    A new method has been developed for coating oilfield core for laboratory studies. It consists of applying a steel coating and aluminum wraps around the outer surface of a core. The strength of the coating, the short time needed to apply it, and its low cost are the major advantages of this new method.

  8. Lateral restraint assembly for reactor core

    DOE Patents [OSTI]

    Gorholt, Wilhelm (San Diego, CA); Luci, Raymond K. (Del Mar, CA)

    1986-01-01T23:59:59.000Z

    A restraint assembly for use in restraining lateral movement of a reactor core relative to a reactor vessel wherein a plurality of restraint assemblies are interposed between the reactor core and the reactor vessel in circumferentially spaced relation about the core. Each lateral restraint assembly includes a face plate urged against the outer periphery of the core by a plurality of compression springs which enable radial preloading of outer reflector blocks about the core and resist low-level lateral motion of the core. A fixed radial key member cooperates with each face plate in a manner enabling vertical movement of the face plate relative to the key member but restraining movement of the face plate transverse to the key member in a plane transverse to the center axis of the core. In this manner, the key members which have their axes transverse to or subtending acute angles with the direction of a high energy force tending to move the core laterally relative to the reactor vessel restrain such lateral movement.

  9. CLOSURE WELD DEVELOPMENT FOR 3013 OUTER CONTAINERS

    SciTech Connect (OSTI)

    Daugherty, W.; Howard, S.; Peterson, K.; Stokes, M.

    2009-11-10T23:59:59.000Z

    Excess plutonium materials in the DOE complex are packaged and stored in accordance with DOE-STD-3013. This standard specifies requirements for the stabilization of such materials and subsequent packaging in dual nested seal-welded containers. Austenitic stainless steels have been selected for container fabrication. The inner 3013 container provides contamination control while the outer 3013 container is the primary containment vessel and is the focus of this paper. Each packaging site chose a process for seal welding the outer 3013 containers in accordance with its needs and expertise. The two processes chosen for weld closure were laser beam welding (LBW) and gas tungsten arc welding (GTAW). Following development efforts, each system was qualified in accordance with DOE-STD-3013 prior to production use. The 3013 outer container closure weld joint was designed to accommodate the characteristics of a laser weld. This aspect of the joint design necessitated some innovative process and equipment considerations in the application of the GTAW process. Details of the weld requirements and the development processes are presented and several potential enhancements for the GTAW system are described.

  10. In Outer Space without a Space Suit?

    E-Print Network [OSTI]

    Alexander Bolonkin

    2008-06-24T23:59:59.000Z

    The author proposes and investigates his old idea - a living human in space without the encumbrance of a complex space suit. Only in this condition can biological humanity seriously attempt to colonize space because all planets of Solar system (except the Earth) do not have suitable atmospheres. Aside from the issue of temperature, a suitable partial pressure of oxygen is lacking. In this case the main problem is how to satiate human blood with oxygen and delete carbonic acid gas (carbon dioxide). The proposed system would enable a person to function in outer space without a space suit and, for a long time, without food. That is useful also in the Earth for sustaining working men in an otherwise deadly atmosphere laden with lethal particulates (in case of nuclear, chemical or biological war), in underground confined spaces without fresh air, under water or a top high mountains above a height that can sustain respiration.

  11. Core Specialization

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisitingContract Management Fermi Site Office (FSO) FSOConvertingCopy ServicesCore

  12. "The Voyager Mission to the Outer Planets and Interstellar Space...

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

    October 17, 2012, 4:15pm Colloquia MBG Auditorium "The Voyager Mission to the Outer Planets and Interstellar Space", Dr. Alan C. Cummings, California Institute of Technology...

  13. Outcome-Space Outer Approximation Algorithm for Linear ...

    E-Print Network [OSTI]

    2007-07-20T23:59:59.000Z

    Jul 20, 2007 ... This paper presents an outcome-space outer approximation algo- rithm for globally solving the linear multiplicative programming prob- lem.

  14. Crystallographic Structure of SurA, a Molecular Chaperone that Facilitates Folding of Outer Membrane Porins

    SciTech Connect (OSTI)

    Bitto, E.

    2002-01-01T23:59:59.000Z

    The SurA protein facilitates correct folding of outer membrane proteins in gram-negative bacteria. The sequence of Escherichia coli SurA presents four segments, two of which are peptidyl-prolyl isomerases (PPIases); the crystal structure reveals an asymmetric dumbbell, in which the amino-terminal, carboxy-terminal, and first PPIase segments of the sequence form a core structural module, and the second PPIase segment is a satellite domain tethered approximately 30 A from this module. The core module, which is implicated in membrane protein folding, has a novel fold that includes an extended crevice. Crystal contacts show that peptides bind within the crevice, suggesting a model for chaperone activity whereby segments of polypeptide may be repetitively sequestered and released during the membrane protein-folding process.

  15. Incorporating Peptides in the Outer Coordination Sphere of Bio-inspired Electrocatalysts for Hydrogen Production

    SciTech Connect (OSTI)

    Jain, Avijita; Lense, Sheri; Linehan, John C.; Raugei, Simone; Cho, Herman M.; DuBois, Daniel L.; Shaw, Wendy J.

    2011-04-01T23:59:59.000Z

    Four new cyclic 1,5-diaza-3,7-diphosphacyclooctane ligands have been prepared and used to synthesize [Ni(PPh2NR2)2]2+ complexes in which R is a mono- or dipeptide. These complexes represent a first step in developing an outer coordination sphere for this class of complexes that can mimic the outer coordination sphere of the active sites of hydrogenase enzymes. Importantly, these complexes retain the electrocatalytic activity of the parent [Ni(PPh2NPh2)2]2+ complex in acetonitrile solution with turnover frequencies (TOF) for hydrogen production ranging from 14 to 25 s-1 in the presence of p-cyanoanilinium trifluoromethanesulphonic acid and 135-1000 s-1 in the presence of triflic acid salt of protonated dimethylformamide, with moderately low overpotentials, ~0.3 V. The addition of small amounts of water result in rate increases of 5-7 times. Unlike the parent complex, these complexes demonstrate dynamic structural transformations in solution whereby the dipeptide tail interacts with the nickel center. These results establish a building block from which larger peptide scaffolding can be added to allow the [Ni(PR2NR’2)2]2+ molecular catalytic core to begin to mimic the multifunctional outer coordination sphere of enzymes. This work was supported by the US Department of Energy Basic Energy Sciences' Chemical Sciences, Geosciences & Biosciences Division. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

  16. Chemical Convention in the Lunar Core from Melting Experiments on the Ironsulfur System

    SciTech Connect (OSTI)

    Li, J.; Liu, J.; Chen, B.; Li, Z.; Wang, Y. (Michigan); (UC)

    2012-03-26T23:59:59.000Z

    By reanalyzing Apollo lunar seismograms using array-processing methods, a recent study suggests that the Moon has a solid inner core and a fluid outer core, much like the Earth. The volume fraction of the lunar inner core is 38%, compared with 4% for the Earth. The pressure at the Moon's core-mantle boundary is 4.8 GPa, and that at the ICB is 5.2 GPa. The partially molten state of the lunar core provides constraints on the thermal and chemical states of the Moon: The temperature at the inner core boundary (ICB) corresponds to the liquidus of the outer core composition, and the mass fraction of the solid core allows us to infer the bulk composition of the core from an estimated thermal profile. Moreover, knowledge on the extent of core solidification can be used to evaluate the role of chemical convection in the origin of early lunar core dynamo. Sulfur is considered an antifreeze component in the lunar core. Here we investigate the melting behavior of the Fe-S system at the pressure conditions of the lunar core, using the multi-anvil apparatus and synchrotron and laboratory-based analytical methods. Our goal is to understand compositionally driven convection in the lunar core and assess its role in generating an internal magnetic field in the early history of the Moon.

  17. Outer core density heterogeneity and the discrepancy between PKP and PcP travel time observations

    E-Print Network [OSTI]

    Boschi, Lapo

    . Soldati Istituto Nazionale di Geofisica e Vulcanologia, Rome, Italy L. Boschi Dipartimento di Fisica, Universita' di Napoli Federico II, Naples, Italy A. Piersanti Istituto Nazionale di Geofisica e Vulcanologia

  18. Electrocatalysts having gold monolayers on platinum nanoparticle cores, and uses thereof

    DOE Patents [OSTI]

    Adzic, Radoslav; Zhang, Junliang

    2010-04-27T23:59:59.000Z

    The invention relates to gold-coated particles useful as fuel cell electrocatalysts. The particles are composed of an electrocatalytically active core at least partially encapsulated by an outer shell of gold or gold alloy. The invention more particularly relates to such particles having a noble metal-containing core, and more particularly, a platinum or platinum alloy core. In other embodiments, the invention relates to fuel cells containing these electrocatalysts and methods for generating electrical energy therefrom.

  19. atlantic outer continental: Topics by E-print Network

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

    was true when the North Atlantic Ocean on multidecadal time scales. That is, a warm (cold) North Atlantic Ocean produces a wet (dry) condition Wang, Chunzai 96 OUTER MEASURE...

  20. Spiral density waves in the outer galactic gaseous discs

    E-Print Network [OSTI]

    Khoperskov, S A

    2015-01-01T23:59:59.000Z

    Deep HI observations of the outer parts of disc galaxies demonstrate the frequent presence of extended, well-developed spiral arms far beyond the optical radius. To understand the nature and the origin of such outer spiral structure, we investigate the propagation in the outer gaseous disc of large-scale spiral waves excited in the bright optical disc. Using hydrodynamical simulations, we show that non-axisymmetric density waves, penetrating in the gas through the outer Lindblad resonance, can exhibit relatively regular spiral structures outside the bright optical stellar disc. For low-amplitude structures, the results of numerical simulations match the predictions of a simple WKB linear theory. The amplitude of spiral structure increases rapidly with radius. Beyond $\\approx 2$ optical radii, spirals become nonlinear (the linear theory becomes quantitatively and qualitatively inadequate) and unstable to Kelvin-Helmholtz instability. In numerical simulations, in models for which gas is available very far out, ...

  1. CORE GAS SLOSHING IN ABELL 1644

    SciTech Connect (OSTI)

    Johnson, Ryan E.; Wegner, Gary A. [Department of Physics and Astronomy, Wilder Lab, Dartmouth College, Hanover, NH 03755 (United States); Markevitch, Maxim; Jones, Christine; Forman, William R., E-mail: ryan.e.johnson@dartmouth.ed, E-mail: gary.a.wegner@bellz.dartmouth.ed, E-mail: mmarkevitch@cfa.harvard.ed, E-mail: cjf@cfa.harvard.ed, E-mail: wrf@cfa.harvard.ed [Smithsonian Astrophysical Observatory, Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)

    2010-02-20T23:59:59.000Z

    We present an analysis of a 72 ks Chandra observation of the double cluster Abell 1644 (z = 0.047). The X-ray temperatures indicate that the masses are M{sub 500} = (2.6 +- 0.4) x 10{sup 14} h {sup -1} M{sub sun} for the northern sub-cluster and M{sub 500} = (3.1 +- 0.4) x 10{sup 14} h {sup -1} M{sub sun} for the southern, main cluster. We identify a sharp edge in the radial X-ray surface brightness of the main cluster, which we find to be a cold front, with a jump in temperature of a factor of {approx}3. This edge possesses a spiral morphology characteristic of core gas sloshing around the cluster potential minimum. We present observational evidence, supported by hydrodynamic simulations, that the northern sub-cluster is the object that initiated the core gas sloshing in the main cluster at least 700 Myr ago. We discuss reheating of the main cluster's core gas via two mechanisms brought about by the sloshing gas: first, the release of gravitational potential energy gained by the core's displacement from the potential minimum, and second, a dredging inward of the outer, higher entropy cluster gas along finger-shaped streams. We find that the available gravitational potential energy is small compared to the energy released by the cooling gas in the core.

  2. The outer filament of Centaurus A as seen by MUSE

    E-Print Network [OSTI]

    Santoro, F; Morganti, R; Oosterloo, T A; Tremblay, G

    2015-01-01T23:59:59.000Z

    We investigate signatures of a jet-interstellar medium (ISM) interaction using optical integral-field observations of the so-called outer filament near Centaurus A, expanding on previous results obtained on a more limited area. Using the Multi Unit Spectroscopic Explorer (MUSE) on the VLT during science verification, we observed a significant fraction of the brighter emitting gas across the outer filament. The ionized gas shows complex morphology with compact blobs, arc-like structures and diffuse emission. Based on the kinematics, we identified three main components. The more collimated component is oriented along the direction of the radio jet. The other two components exhibit diffuse morphology together with arc-like structures also oriented along the radio jet direction. Furthermore, the ionization level of the gas is found to decrease from the more collimated component to the more diffuse components. The morphology and velocities of the more collimated component confirm our earlier results that the outer...

  3. Core Drilling Demonstration

    Broader source: Energy.gov [DOE]

    Tank Farms workers demonstrate core drilling capabilities for Hanford single-shell tanks. Core drilling is used to determine the current condition of each tank to assist in the overall assessment...

  4. Plasma in the outer heliosphere and the heliosheath

    E-Print Network [OSTI]

    Richardson, John

    from from 2004 to 2006.1. The top panel shows the solar wind speed, the middle panel the solar wind dynamic pressure, and the bottom panel the >0.5 MeV ion counting rate. From mid-2002 to mid-2005 the solar in the outer heliosphere. We present recent data which shows that the solar wind speed is decreasing

  5. Heating the Outer Heliosphere by Pickup Charles W. Smith

    E-Print Network [OSTI]

    Richardson, John

    Heating the Outer Heliosphere by Pickup Protons Charles W. Smith£ , Philip A. Isenberg£ , William H the ability of a turbulent cascade within the solar wind to heat the thermal protons. Several sources of energy are required to accom- plish the observed heating. Wind shear and shocks originating

  6. Annular core liquid-salt cooled reactor with multiple fuel and blanket zones

    DOE Patents [OSTI]

    Peterson, Per F.

    2013-05-14T23:59:59.000Z

    A liquid fluoride salt cooled, high temperature reactor having a reactor vessel with a pebble-bed reactor core. The reactor core comprises a pebble injection inlet located at a bottom end of the reactor core and a pebble defueling outlet located at a top end of the reactor core, an inner reflector, outer reflector, and an annular pebble-bed region disposed in between the inner reflector and outer reflector. The annular pebble-bed region comprises an annular channel configured for receiving pebble fuel at the pebble injection inlet, the pebble fuel comprising a combination of seed and blanket pebbles having a density lower than the coolant such that the pebbles have positive buoyancy and migrate upward in said annular pebble-bed region toward the defueling outlet. The annular pebble-bed region comprises alternating radial layers of seed pebbles and blanket pebbles.

  7. 2 Geomagnetic dipole moment collapse by convective mixing in the core 3 Lijun Liu1

    E-Print Network [OSTI]

    Olson, Peter L.

    through 13 expulsion of mostly poloidal magnetic field by convective 14 upwellings. The dipole fieldkinematic dynamo waves [Gubbins, 1987]. Like resistive 58instabilities, dynamo wave mechanisms are limited on relatively long time scales 61in the outer core. 62[4] Numerical dynamos reveal there are fast, advection- 63

  8. Experimental constraints on the thermodynamics and sound velocities of hcp-Fe to core pressures

    E-Print Network [OSTI]

    Jackson, Jennifer M.

    that comprises the volume-dependent phonon density of states (DOS) of e-Fe at eleven compression points. From information about the partitioning behavior of iron isotopes in equilibrium processes involving solid e providing a new tight constraint on the density dependence of e-Fe's sound velocities to outer core

  9. Manipulation of emission energy in GaAs/AlGaAs core-shell nanowires with radial heterostructure

    SciTech Connect (OSTI)

    Barbosa, B. G.; Arakaki, H.; Souza, C. A. de; Pusep, Yu. A. [Instituto de Fisica de São Carlos, Universidade de São Paulo, 13560-970 Sao Carlos, SP (Brazil)

    2014-03-21T23:59:59.000Z

    Photoluminescence was studied in GaAs/AlGaAs nanowires (NWs) with different radial heterostructures. We demonstrated that manipulation of the emission energy may be achieved by appropriate choice of the shell structure. The emission at highest energy is generated in the NWs with tunneling thin AlGaAs inner shell and thin GaAs outer shell due to recombination of the photoexcited electrons confined in the outer shell with the holes in the core. Lower energy emission was shown to occur in the NWs with thick outer shell grown in the form of a short-period GaAs/AlGaAs multiple quantum well structure. In this case, the tunneling probability through the multiple quantum wells controls the energy emitted by the NWs. The doping of core results in dominated low energy emission from the GaAs core.

  10. On the outer boundary of the sunspot penumbra

    E-Print Network [OSTI]

    B. Kalman

    2002-02-06T23:59:59.000Z

    Comparison of photographic observations and vector-magnetograph measurements demonstrate, that the outer boundary of the sunspot penumbra --even in complex sunspot groups-- closely follows the 0.075T isogauss line of the total value of the magnetic field, corresponding approximately to the equipartition value in the photosphere. Radio observations also show this feature. The thick penumbra model with interchange convection (Jahn and Schmidt, 1994) gives the best explanation of the penumbral structure.

  11. Structural basis for alginate secretion across the bacterial outer membrane

    SciTech Connect (OSTI)

    Whitney, J.C.; Robinson, H.; Hay, I. D.; Li, C.; Eckford, P. D. W.; Amaya, M. F.; Wood, L. F.; Ohman, D. E.; Bear, C. E.; Rehm, B. H.; Howell, P. L.

    2011-08-09T23:59:59.000Z

    Pseudomonas aeruginosa is the predominant pathogen associated with chronic lung infection among cystic fibrosis patients. During colonization of the lung, P. aeruginosa converts to a mucoid phenotype characterized by the overproduction of the exopolysaccharide alginate. Secretion of newly synthesized alginate across the outer membrane is believed to occur through the outer membrane protein AlgE. Here we report the 2.3 {angstrom} crystal structure of AlgE, which reveals a monomeric 18-stranded {beta}-barrel characterized by a highly electropositive pore constriction formed by an arginine-rich conduit that likely acts as a selectivity filter for the negatively charged alginate polymer. Interestingly, the pore constriction is occluded on either side by extracellular loop L2 and an unusually long periplasmic loop, T8. In halide efflux assays, deletion of loop T8 ({Delta}T8-AlgE) resulted in a threefold increase in anion flux compared to the wild-type or {Delta}L2-AlgE supporting the idea that AlgE forms a transport pathway through the membrane and suggesting that transport is regulated by T8. This model is further supported by in vivo experiments showing that complementation of an algE deletion mutant with {Delta}T8-AlgE impairs alginate production. Taken together, these studies support a mechanism for exopolysaccharide export across the outer membrane that is distinct from the Wza-mediated translocation observed in canonical capsular polysaccharide export systems.

  12. The Role of a Dipeptide Outer-Coordination Sphere on H2 -Production...

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

    Dipeptide Outer-Coordination Sphere on H2 -Production Catalysts: Influence on Catalytic Rates and Electron The Role of a Dipeptide Outer-Coordination Sphere on H2 -Production...

  13. New mineralogy of the outer solar system and the high-pressure behaviour of methane 

    E-Print Network [OSTI]

    Maynard-Casely, Helen E.

    2009-01-01T23:59:59.000Z

    This thesis will introduce the study of methane as a mineral. Along with ammonia and water, methane is one of the main planetary-forming materials in the outer solar system. The topic of `new mineralogy of the outer solar ...

  14. Secure Core Contact Information

    E-Print Network [OSTI]

    Secure Core Contact Information C. E. Irvine irvine@nps.edu 831-656-2461 Department of Computer for the secure management of local and/or remote information in multiple contexts. The SecureCore project Science Graduate School of Operations and Information Sciences www.cisr.nps.edu Project Description

  15. Core shroud corner joints

    DOE Patents [OSTI]

    Gilmore, Charles B.; Forsyth, David R.

    2013-09-10T23:59:59.000Z

    A core shroud is provided, which includes a number of planar members, a number of unitary corners, and a number of subassemblies each comprising a combination of the planar members and the unitary corners. Each unitary corner comprises a unitary extrusion including a first planar portion and a second planar portion disposed perpendicularly with respect to the first planar portion. At least one of the subassemblies comprises a plurality of the unitary corners disposed side-by-side in an alternating opposing relationship. A plurality of the subassemblies can be combined to form a quarter perimeter segment of the core shroud. Four quarter perimeter segments join together to form the core shroud.

  16. Turbine exhaust diffuser with region of reduced flow area and outer boundary gas flow

    DOE Patents [OSTI]

    Orosa, John

    2014-03-11T23:59:59.000Z

    An exhaust diffuser system and method for a turbine engine. The outer boundary may include a region in which the outer boundary extends radially inwardly toward the hub structure and may direct at least a portion of an exhaust flow in the diffuser toward the hub structure. At least one gas jet is provided including a jet exit located on the outer boundary. The jet exit may discharge a flow of gas downstream substantially parallel to an inner surface of the outer boundary to direct a portion of the exhaust flow in the diffuser toward the outer boundary to effect a radially outward flow of at least a portion of the exhaust gas flow toward the outer boundary to balance an aerodynamic load between the outer and inner boundaries.

  17. Midland Core Repository

    SciTech Connect (OSTI)

    Tyler, Noel

    2000-08-14T23:59:59.000Z

    This report summarizes activities for the repository during this quarter. The repository holds drill cores and cuttings samples from oil wells that can be viewed or checked out by users.

  18. Emergency core cooling system

    DOE Patents [OSTI]

    Schenewerk, William E. (Sherman Oaks, CA); Glasgow, Lyle E. (Westlake Village, CA)

    1983-01-01T23:59:59.000Z

    A liquid metal cooled fast breeder reactor provided with an emergency core cooling system includes a reactor vessel which contains a reactor core comprising an array of fuel assemblies and a plurality of blanket assemblies. The reactor core is immersed in a pool of liquid metal coolant. The reactor also includes a primary coolant system comprising a pump and conduits for circulating liquid metal coolant to the reactor core and through the fuel and blanket assemblies of the core. A converging-diverging venturi nozzle with an intermediate throat section is provided in between the assemblies and the pump. The intermediate throat section of the nozzle is provided with at least one opening which is in fluid communication with the pool of liquid sodium. In normal operation, coolant flows from the pump through the nozzle to the assemblies with very little fluid flowing through the opening in the throat. However, when the pump is not running, residual heat in the core causes fluid from the pool to flow through the opening in the throat of the nozzle and outwardly through the nozzle to the assemblies, thus providing a means of removing decay heat.

  19. MCNP LWR Core Generator

    SciTech Connect (OSTI)

    Fischer, Noah A. [Los Alamos National Laboratory

    2012-08-14T23:59:59.000Z

    The reactor core input generator allows for MCNP input files to be tailored to design specifications and generated in seconds. Full reactor models can now easily be created by specifying a small set of parameters and generating an MCNP input for a full reactor core. Axial zoning of the core will allow for density variation in the fuel and moderator, with pin-by-pin fidelity, so that BWR cores can more accurately be modeled. LWR core work in progress: (1) Reflectivity option for specifying 1/4, 1/2, or full core simulation; (2) Axial zoning for moderator densities that vary with height; (3) Generating multiple types of assemblies for different fuel enrichments; and (4) Parameters for specifying BWR box walls. Fuel pin work in progress: (1) Radial and azimuthal zoning for generating further unique materials in fuel rods; (2) Options for specifying different types of fuel for MOX or multiple burn assemblies; (3) Additional options for replacing fuel rods with burnable poison rods; and (4) Control rod/blade modeling.

  20. Core Values | Department of Energy

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

    Core Values Core Values People - People are our most important resource. We respect and use our experience and skills and appreciate our diversity. Business Excellence - We are...

  1. Magnetic Fields in Molecular Cloud Cores

    E-Print Network [OSTI]

    Shantanu Basu

    2004-10-22T23:59:59.000Z

    Observations of magnetic field strengths imply that molecular cloud fragments are individually close to being in a magnetically critical state, even though both magnetic field and column density measurements range over two orders of magnitude. The turbulent pressure also approximately balances the self-gravitational pressure. These results together mean that the one-dimensional velocity dispersion $\\sigv$ is proportional to the mean \\Alf speed of a cloud $\\va$. Global models of MHD turbulence in a molecular cloud show that this correlation is naturally satisfied for a range of different driving strengths of the turbulence. For example, an increase of turbulent driving causes a cloud expansion which also increases $\\va$. Clouds are in a time averaged balance but exhibit large oscillatory motions, particularly in their outer rarefied regions. We also discuss models of gravitational fragmentation in a sheet-like region in which turbulence has already dissipated, including the effects of magnetic fields and ion-neutral friction. Clouds with near-critical mass-to-flux ratios lead to subsonic infall within cores, consistent with some recent observations of motions in starless cores. Conversely, significantly supercritical clouds are expected to produce extended supersonic infall.

  2. Coalescence of bubbles and drops in an outer fluid

    E-Print Network [OSTI]

    Joseph D. Paulsen; Rémi Carmigniani; Anerudh Kannan; Justin C. Burton; Sidney R. Nagel

    2014-07-24T23:59:59.000Z

    When two liquid drops touch, a microscopic connecting liquid bridge forms and rapidly grows as the two drops merge into one. Whereas coalescence has been thoroughly studied when drops coalesce in vacuum or air, many important situations involve coalescence in a dense surrounding fluid, such as oil coalescence in brine. Here we study the merging of gas bubbles and liquid drops in an external fluid. Our data indicate that the flows occur over much larger length scales in the outer fluid than inside the drops themselves. Thus we find that the asymptotic early regime is always dominated by the viscosity of the drops, independent of the external fluid. A phase diagram showing the crossovers into the different possible late-time dynamics identifies a dimensionless number that signifies when the external viscosity can be important.

  3. Potential alternative energy technologies on the Outer Continental Shelf.

    SciTech Connect (OSTI)

    Elcock, D.; Environmental Assessment

    2007-04-20T23:59:59.000Z

    This technical memorandum (TM) describes the technology requirements for three alternative energy technologies for which pilot and/or commercial projects on the U.S. Outer Continental Shelf (OCS) are likely to be proposed within the next five to seven years. For each of the alternative technologies--wind, wave, and ocean current--the TM first presents an overview. After each technology-specific overview, it describes the technology requirements for four development phases: site monitoring and testing, construction, operation, and decommissioning. For each phase, the report covers the following topics (where data are available): facility description, electricity generated, ocean area (surface and bottom) occupied, resource requirements, emissions and noise sources, hazardous materials stored or used, transportation requirements, and accident potential. Where appropriate, the TM distinguishes between pilot-scale (or demonstration-scale) facilities and commercial-scale facilities.

  4. A DETAILED KINEMATIC MAP OF CASSIOPEIA A'S OPTICAL MAIN SHELL AND OUTER HIGH-VELOCITY EJECTA

    SciTech Connect (OSTI)

    Milisavljevic, Dan [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA, 02138 (United States); Fesen, Robert A., E-mail: dmilisav@cfa.harvard.edu [6127 Wilder Lab, Department of Physics and Astronomy, Dartmouth College, Hanover, NH 03755 (United States)

    2013-08-01T23:59:59.000Z

    We present three-dimensional (3D) kinematic reconstructions of optically emitting material in the young Galactic supernova remnant Cassiopeia A (Cas A). These Doppler maps have the highest spectral and spatial resolutions of any previous survey of Cas A and represent the most complete catalog of its optically emitting material to date. We confirm that the bulk of Cas A's optically bright ejecta populate a torus-like geometry tilted approximately 30 Degree-Sign with respect to the plane of the sky with a -4000 to +6000 km s{sup -1} radial velocity asymmetry. Near-tangent viewing angle effects and an inhomogeneous surrounding circumstellar material/interstellar medium environment suggest that this geometry and velocity asymmetry may not be faithfully representative of the remnant's true 3D structure or the kinematic properties of the original explosion. The majority of the optical ejecta are arranged in several well-defined and nearly circular ring-like structures with diameters between approximately 30'' (0.5 pc) and 2' (2 pc). These ejecta rings appear to be a common phenomenon of young core-collapse remnants and may be associated with post-explosion input of energy from plumes of radioactive {sup 56}Ni-rich ejecta that rise, expand, and compress non-radioactive material. Our optical survey encompasses Cas A's faint outlying ejecta knots and exceptionally high-velocity NE and SW streams of S-rich debris often referred to as ''jets''. These outer knots, which exhibit a chemical make-up suggestive of an origin deep within the progenitor star, appear to be arranged in opposing and wide-angle outflows with opening half-angles of Almost-Equal-To 40 Degree-Sign.

  5. Storm/substorm signatures in the outer belt

    SciTech Connect (OSTI)

    Korth, A.; Friedel, R.H.W.; Mouikis, C. [Max-Planck-Inst. fuer Aeronomie, Lindau (Germany); Fennell, J.F. [Aerospace Corp., El Segundo, CA (United States)

    1998-12-01T23:59:59.000Z

    The response of the ring current region is compared for periods of storm and substorm activity, with an attempt to isolate the contributions of both processes. The authors investigate CRRES particle data in an overview format that allows the display of long-term variations of the outer radiation belt. They compare the evolution of the ring current population to indicators of storm (Dst) and substorm (AE) activity and examine compositional changes. Substorm activity leads to the intensification of the ring current at higher L (L {approximately} 6) and lower ring current energies compared to storms (L {approximately} 4). The O{sup +}/H{sup +} ratio during substorms remains low, near 10%, but is much enhanced during storms (can exceed 100%). They conclude that repeated substorms with an AE {approximately} 900 nT lead to a {Delta}Dst of {approximately} 30 nT, but do not contribute to Dst during storm main phase as substorm injections do not form a symmetric ring current during such disturbed times.

  6. GRAIN SORTING IN COMETARY DUST FROM THE OUTER SOLAR NEBULA

    SciTech Connect (OSTI)

    Wozniakiewicz, P. J.; Bradley, J. P.; Ishii, H. A. [Institute of Geophysics and Planetary Physics, Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Brownlee, D. E. [Department of Astronomy, University of Washington, Seattle, WA (United States); Kearsley, A. T. [Department of Mineralogy, Natural History Museum, London SW7 5BD (United Kingdom); Burchell, M. J.; Price, M. C., E-mail: P.Wozniakiewicz@kent.ac.uk [School of Physical Sciences, University of Kent, Canterbury, Kent CT2 7NH (United Kingdom)

    2012-12-01T23:59:59.000Z

    Most young stars are surrounded by a disk of gas and dust. Close to the hot stars, amorphous dust grains from the parent molecular cloud are reprocessed into crystals that are then distributed throughout the accretion disk. In some disks, there is a reduction in crystalline grain size with heliocentric distance from the star. We investigated crystalline grain size distributions in chondritic porous (CP) interplanetary dust particles (IDPs) believed to be from small, icy bodies that accreted in outer regions of the solar nebula. The grains are Mg-rich silicates and Fe-rich sulfides, the two most abundant minerals in CP IDPs. We find that they are predominantly <0.25 {mu}m in radius with a mean grain size that varies from one CP IDP to another. We report a size-density relationship between the silicates and sulfides. A similar size-density relationship between much larger silicate and sulfide grains in meteorites from the asteroid belt is ascribed to aerodynamic sorting. Since the silicate and sulfide grains in CP IDPs are theoretically too small for aerodynamic sorting, their size-density relationship may be due to another process capable of sorting small grains.

  7. Exploring the Outer Solar System with the ESSENCE Supernova Survey

    SciTech Connect (OSTI)

    Becker, A.C.; /Washington U., Seattle, Astron. Dept.; Arraki, K.; /Washington U., Seattle, Astron. Dept.; Kaib, N.A.; /Washington U., Seattle, Astron. Dept.; Wood-Vasey, W.M.; /Harvard-Smithsonian Ctr. Astrophys.; Aguilera, C.; /Cerro-Tololo InterAmerican Obs.; Blackman, J.W.; /Australian Natl. U., Canberra; Blondin, S.; /Harvard-Smithsonian Ctr. Astrophys.; Challis, P.; /Harvard-Smithsonian Ctr. Astrophys.; Clocchiatti, A.; /Rio de Janeiro, Pont. U. Catol.; Covarrubias, R.; /Kyushu Sangyo U.; Damke, G.; /Cerro-Tololo InterAmerican Obs.; Davis, T.M.; /Bohr Inst. /Queensland U.; Filippenko, A.V.; /UC, Berkeley; Foley, R.J.; /UC, Berkeley; Garg, A.; /Harvard-Smithsonian Ctr. Astrophys. /Harvard U.; Garnavich, P.M.; /Notre Dame U.; Hicken, M.; /Harvard-Smithsonian Ctr. Astrophys. /Harvard U.; Jha, S.; /Harvard U. /SLAC; Kirshner, R.P.; /Harvard-Smithsonian Ctr. Astrophys.; Krisciunas, K.; /Notre Dame U. /Texas A-M; Leibundgut, B.; /Munich, Tech. U. /UC, Berkeley /NOAO, Tucson /Washington U., Seattle, Astron. Dept. /Fermilab /Harvard-Smithsonian Ctr. Astrophys. /Harvard U. /Chile U., Santiago /Ohio State U. /Cerro-Tololo InterAmerican Obs. /Harvard U. /Baltimore, Space Telescope Sci. /Johns Hopkins U. /Australian Natl. U., Canberra /Australian Natl. U., Canberra /Cerro-Tololo InterAmerican Obs. /Munich, Tech. U. /Harvard-Smithsonian Ctr. Astrophys. /Harvard U. /Cerro-Tololo InterAmerican Obs. /Texas A-M /Cerro-Tololo InterAmerican Obs.

    2011-11-10T23:59:59.000Z

    We report the discovery and orbital determination of 14 trans-Neptunian objects (TNOs) from the ESSENCE Supernova Survey difference imaging data set. Two additional objects discovered in a similar search of the SDSS-II Supernova Survey database were recovered in this effort. ESSENCE repeatedly observed fields far from the solar system ecliptic (-21{sup o} < {beta} < -5{sup o}), reaching limiting magnitudes per observation of I {approx} 23.1 and R {approx} 23.7. We examine several of the newly detected objects in detail, including 2003 UC{sub 414}, which orbits entirely between Uranus and Neptune and lies very close to a dynamical region that would make it stable for the lifetime of the solar system. 2003 SS{sub 422} and 2007 TA{sub 418} have high eccentricities and large perihelia, making them candidate members of an outer class of TNOs. We also report a new member of the 'extended' or 'detached' scattered disk, 2004 VN{sub 112}, and verify the stability of its orbit using numerical simulations. This object would have been visible to ESSENCE for only {approx}2% of its orbit, suggesting a vast number of similar objects across the sky. We emphasize that off-ecliptic surveys are optimal for uncovering the diversity of such objects, which in turn will constrain the history of gravitational influences that shaped our early solar system.

  8. Logic-Based Outer-Approximation Algorithm for Solving Discrete-Continuous Dynamic

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    In this work we present an extension of the Logic Outer-Approximation algorithm for deal- ing with disjunctive.e. the control actions) may involve logic decisions that can be modeled as disjunctions [16], [17] giving riseLogic-Based Outer-Approximation Algorithm for Solving Discrete-Continuous Dynamic Optimization

  9. Are energetic electrons in the solar wind the source of the outer radiation belt?

    E-Print Network [OSTI]

    Li, Xinlin

    Are energetic electrons in the solar wind the source of the outer radiation belt? Xinlin Li,1 D. N in the solar wind are the source of the outer rela- tivistic electron radiation belt. Though there is some radiation belt, the phase space density of 20-200 keV electrons in the solar wind is not adequate to supply

  10. A parametric study of the source rate for outer radiation belt electrons using a Kalman filter

    E-Print Network [OSTI]

    Li, Xinlin

    A parametric study of the source rate for outer radiation belt electrons using a Kalman filter Q increasingly popular to describe the outer radiation belt energetic electron environment. We use a Kalman included. We augment the Kalman filter to include the intensity of local acceleration in the state vector

  11. The Solar Wind in the Outer Heliosphere at Solar John D. Richardson and Chi Wang

    E-Print Network [OSTI]

    Richardson, John

    The Solar Wind in the Outer Heliosphere at Solar Maximum John D. Richardson and Chi Wang Center solar wind observations in the outer heliosphere, concentrating on the recent data near solar maximum. The speed and temperature tend to be lower at solar maximum, due to the lack of coronal holes. The near

  12. 1. THE RADIATION BELTS The outer zone radiation belts consist of energetic elec-

    E-Print Network [OSTI]

    Elkington, Scot R.

    1. THE RADIATION BELTS The outer zone radiation belts consist of energetic elec- trons trapped in the geomagnetic field. The dynamics of the belts are dictated by the global and local electric and mag- netic electrons in the outer zone and electric and magnetic field variations occurring on ULF time scales

  13. Variable depth core sampler

    DOE Patents [OSTI]

    Bourgeois, P.M.; Reger, R.J.

    1996-02-20T23:59:59.000Z

    A variable depth core sampler apparatus is described comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member. 7 figs.

  14. Core-collapse Supernovae

    SciTech Connect (OSTI)

    Hix, William Raphael [ORNL; Lentz, E. J. [University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL); Baird, Mark L [ORNL; Chertkow, Merek A [ORNL; Lee, Ching-Tsai [University of Tennessee, Knoxville (UTK); Blondin, J. M. [North Carolina State University; Bruenn, S. W. [Florida Atlantic University, Boca Raton; Messer, Bronson [ORNL; Mezzacappa, Anthony [ORNL

    2013-01-01T23:59:59.000Z

    Marking the inevitable death of a massive star, and the birth of a neutron star or black hole, core-collapse supernovae bring together physics at a wide range in spatial scales, from kilometer-sized hydrodynamic motions (growing to gigameter scale) down to femtometer scale nuclear reactions. Carrying 10$^{51}$ ergs of kinetic energy and a rich-mix of newly synthesized atomic nuclei, core-collapse supernovae are the preeminent foundries of the nuclear species which make up ourselves and our solar system. We will discuss our emerging understanding of the convectively unstable, neutrino-driven explosion mechanism, based on increasingly realistic neutrino-radiation hydrodynamic simulations that include progressively better nuclear and particle physics. Recent multi-dimensional models with spectral neutrino transport from several research groups, which slowly develop successful explosions for a range of progenitors, have motivated changes in our understanding of the neutrino reheating mechanism. In a similar fashion, improvements in nuclear physics, most notably explorations of weak interactions on nuclei and the nuclear equation of state, continue to refine our understanding of how supernovae explode. Recent progress on both the macroscopic and microscopic effects that affect core-collapse supernovae are discussed.

  15. Aging and Phase Stability of Waste Package Outer Barrier

    SciTech Connect (OSTI)

    F. Wong

    2004-09-28T23:59:59.000Z

    This report was prepared in accordance with ''Technical Work Plan for: Regulatory Integration Modeling and Analysis of the Waste Form and Waste Package'' (BSC 2004 [DIRS 171583]). This report provides information on the phase stability of Alloy 22, the current waste package outer barrier material. The goal of this model is to determine whether the single-phase solid solution is stable under repository conditions and, if not, how fast other phases may precipitate. The aging and phase stability model, which is based on fundamental thermodynamic and kinetic concepts and principles, will be used to provide predictive insight into the long-term metallurgical stability of Alloy 22 under relevant repository conditions. The results of this model are used by ''General Corrosion and Localized Corrosion of Waste Package Outer Barrier'' as reference-only information. These phase stability studies are currently divided into three general areas: Tetrahedrally close-packed (TCP) phase and carbide precipitation in the base metal; TCP and carbide precipitation in welded samples; and Long-range ordering reactions. TCP-phase and carbide precipitates that form in Alloy 22 are generally rich in chromium (Cr) and/or molybdenum (Mo) (Raghavan et al. 1984 [DIRS 154707]). Because these elements are responsible for the high corrosion resistance of Alloy 22, precipitation of TCP phases and carbides, especially at grain boundaries, can lead to an increased susceptibility to localized corrosion in the alloy. These phases are brittle and also tend to embrittle the alloy (Summers et al. 1999 [DIRS 146915]). They are known to form in Alloy 22 at temperatures greater than approximately 600 C. Whether these phases also form at the lower temperatures expected in the repository during the 10,000-year regulatory period must be determined. The kinetics of this precipitation will be determined for both the base metal and the weld heat-affected zone (HAZ). The TCP phases (P, {mu}, and {sigma}) are present in the weld metal in the as-welded condition. It may be possible to eliminate these phases through a solution anneal heat treatment, but that may not be possible for the closure weld because the spent nuclear fuel cladding cannot be heated to more than 350 C. The effects of any stress mitigation techniques (such as laser peening or solution heat treating) that may be used to reduce the tensile stresses on the closure welds must also be determined. Cold-work will cause an increase in dislocation density, and such an increase in dislocation density may cause an increase in diffusion rates that control precipitation kinetics (Porter et al. 1992 [DIRS 161265]; Tawancy et al. 1983 [DIRS 104991]). Long-range order (LRO) occurs in nickel (Ni)-Cr-Mo alloys (such as Alloy 22) at temperatures less than approximately 600 C. This ordering has been linked to an increased susceptibility of Ni-Cr-Mo alloys to stress corrosion cracking and hydrogen embrittlement (Tawancy et al. 1983 [DIRS 104991]). These analyses provide information on the rate at which LRO may occur in Alloy 22 under repository conditions. Determination of the kinetics of transformations through experimental techniques requires that the transformations being investigated be accelerated due to the fact that the expected service life is at least 10,000 years. Phase transformations are typically accelerated through an increase in temperature. The rate of transformation is determined at the higher temperature and is extrapolated to the lower temperatures of interest.

  16. ARM - Ice Cores

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006Datastreamstwrcam40m DocumentationJanuary 9, 2009 [Events, FeatureListGeneralPastIce Cores Outreach Home Room

  17. 2001 BTS Core Databook

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch >InternshipDepartment of Energy with6, 2014, 6:32 p.m. (MST)BTS CORE

  18. Measurements of DT alpha particle loss near the outer midplane of TFTR

    SciTech Connect (OSTI)

    Zweben, S.J.; Darrow, D.S.; Herrmann, H.W.; Redi, M.H.; Schivell, J.; White, R.B.

    1995-07-01T23:59:59.000Z

    Measurements of DT alpha particle loss to the outer midplane region of TFTR have been made using a radially movable scintillator detector. The conclusion from this data is that mechanisms determining the DT alpha loss to the outer midplane are not substantially different from those for DD fusion products. Some of these results are compared with a simplified theoretical model for TF ripple-induced alpha loss, which is expected to be the dominant classical alpha loss mechanism near the outer midplane. An example of plasma-driven MHD-induced alpha particle loss is shown, but no signs of any ``collective`` alpha instability-induced alpha loss have yet been observed.

  19. Particle trap to sheath contact for a gas-insulated transmission line having a corrugated outer conductor

    DOE Patents [OSTI]

    Fischer, William H. (Pittsburgh, PA); Cookson, Alan H. (Pittsburgh, PA); Yoon, Kue H. (Pittsburgh, PA)

    1984-04-10T23:59:59.000Z

    A particle trap to outer elongated conductor or sheath contact for gas-insulated transmission lines. The particle trap to outer sheath contact of the invention is applicable to gas-insulated transmission lines having either corrugated or non-corrugated outer sheaths. The contact of the invention includes an electrical contact disposed on a lever arm which in turn is rotatably disposed on the particle trap and biased in a direction to maintain contact between the electrical contact and the outer sheath.

  20. Coupling between JET Pedestal ne-Te and Outer Target Plate Recycling: Consequences for JET ITER-Like-Wall Operation

    E-Print Network [OSTI]

    Coupling between JET Pedestal ne-Te and Outer Target Plate Recycling: Consequences for JET ITER-Like-Wall Operation

  1. Effect of outer hair cell piezoelectricity on high-frequency receptor potentials

    E-Print Network [OSTI]

    Popel, Aleksander S.

    The low-pass voltage response of outer hair cells predicted by conventional equivalent circuit analysis, 1996; Ruggero, 1992 . Passive vibration of the basilar membrane and tecto- rial membrane in the cochlea

  2. Kinetics of Reduction of Fe(III) Complexes by Outer Membrane...

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

    outer-membrane cytochromes, particularly MtrC and OmcA, are suspected to function as terminal reductases and are responsible for its enzymatic catalysis capability. So far, the...

  3. Turbine airfoil with dual wall formed from inner and outer layers separated by a compliant structure

    DOE Patents [OSTI]

    Campbell; Christian X. (Oviedo, FL), Morrison; Jay A. (Oviedo, FL)

    2011-12-20T23:59:59.000Z

    A turbine airfoil usable in a turbine engine with a cooling system and a compliant dual wall configuration configured to enable thermal expansion between inner and outer layers while eliminating stress formation is disclosed. The compliant dual wall configuration may be formed a dual wall formed from inner and outer layers separated by a compliant structure. The compliant structure may be configured such that the outer layer may thermally expand without limitation by the inner layer. The compliant structure may be formed from a plurality of pedestals positioned generally parallel with each other. The pedestals may include a first foot attached to a first end of the pedestal and extending in a first direction aligned with the outer layer, and may include a second foot attached to a second end of the pedestal and extending in a second direction aligned with the inner layer.

  4. Identification and Characterization of UndA-HRCR-6, an Outer...

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

    MR-1 mutant’s ability to reduce solid phase ferrihydrite at 40% of that for MR-1 wild type, (ii) increased extracellular formation of UO2 associated with the outer membrane...

  5. Transport of Magnetic Fields in Convective, Accreting Supernova Cores

    E-Print Network [OSTI]

    Christopher Thompson; Norman Murray

    2001-05-24T23:59:59.000Z

    We consider the amplification and transport of a magnetic field in the collapsed core of a massive star, including both the region between the neutrinosphere and the shock, and the central, opaque core. An analytical argument explains why rapid convective overturns persist within a newly formed neutron star for roughly 10 seconds ($> 10^3$ overturns), consistent with recent numerical models. A dynamical balance between turbulent and magnetic stresses within this convective layer corresponds to flux densities in excess of $10^{15}$G. Material accreting onto the core is heated by neutrinos and also becomes strongly convective. We compare the expected magnetic stresses in this convective `gain layer' with those deep inside the neutron core. Buoyant motions of magnetized fluid are greatly aided by the intense neutrino flux. We calculate the transport rate through a medium containing free neutrons protons, and electrons, in the limiting cases of degenerate or non-degenerate nucleons. Fields stronger than $\\sim 10^{13}$ G are able to rise through the outer degenerate layers of the neutron core during the last stages of Kelvin-Helmholtz cooling (up to 10 seconds post-collapse), even though these layers have become stable to convection. We also find the equilibrium shape of a thin magnetic flux rope in the dense hydrostatic atmosphere of the neutron star, along with the critical separation of the footpoints above which the rope undergoes unlimited expansion against gravity. The implications of these results for pulsar magnetism are summarized, and applied to the case of late fallback over the first 1,000-10,000 s of the life of a neutron star

  6. Evidence for a New Elliptical-Galaxy Paradigm: Sersic and Core Galaxies

    E-Print Network [OSTI]

    I. Trujillo; Peter Erwin; A. Asensio Ramos; Alister W. Graham

    2004-03-29T23:59:59.000Z

    We fit the surface-brightness profiles of 21 elliptical galaxies using both the Sersic function and a new empirical model which combines an inner power law with an outer Sersic function. The profiles are combinations of deconvolved HST profiles from the literature and ellipse fits to the full WFPC2 mosaic images, and thus span a radial range from ~ 0.02 arcsec to ~ twice the half-light radius. We are able to accurately fit the entire profiles using either the Sersic function or our new model. In doing so, we demonstrate that most, if not all, so-called ``power-law'' galaxies are better described as ``Sersic galaxies'' -- they are well modeled by the three-parameter Sersic profile into the limits of HST resolution -- and that ``core'' galaxies are best understood as consisting of an outer Sersic profile with an inner power-law cusp, which is a downward deviation from the inward extrapolation of the Sersic profile. This definition of cores resolves ambiguities that result when the popular ``Nuker law'' is fitted to the profiles of ellipticals and bulges, particularly at lower luminosities. We also find that using the Nuker law to model core-galaxy nuclear profiles systematically overestimates the core radii by factors of 1.5--4.5 and underestimates the inner power-law slope by ~ 20--40% or more.

  7. HTTF Core Stress Analysis

    SciTech Connect (OSTI)

    Brian D. Hawkes; Richard Schultz

    2012-07-01T23:59:59.000Z

    In accordance with the need to determine whether cracking of the ceramic core disks which will be constructed and used in the High Temperature Test Facility (HTTF) for heatup and cooldown experiments, a set of calculation were performed using Abaqus to investigate the thermal stresses levels and likelihood for cracking. The calculations showed that using the material properties provided for the Greencast 94F ceramic, cracking is predicted to occur. However, this modeling does not predict the size or length of the actual cracks. It is quite likely that cracks will be narrow with rough walls which would impede the flow of coolant gases entering the cracks. Based on data recorded at Oregon State University using Greencast 94F samples that were heated and cooled at prescribed rates, it was concluded that the likelihood that the cracks would be detrimental to the experimental objectives is small.

  8. OPTICAL COLORS OF INTRACLUSTER LIGHT IN THE VIRGO CLUSTER CORE

    SciTech Connect (OSTI)

    Rudick, Craig S.; Mihos, J. Christopher; Harding, Paul; Morrison, Heather L. [Department of Astronomy, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106 (United States); Feldmeier, John J. [Department of Physics and Astronomy, Youngstown State University, Youngstown, OH 44555 (United States); Janowiecki, Steven, E-mail: csr10@case.ed [Department of Astronomy, Indiana University, 727 East 3rd Street, Bloomington, IN 47405 (United States)

    2010-09-01T23:59:59.000Z

    We continue our deep optical imaging survey of the Virgo cluster using the CWRU Burrell Schmidt telescope by presenting B-band surface photometry of the core of the Virgo cluster in order to study the cluster's intracluster light (ICL). We find ICL features down to {mu}{sub B} {approx}29 mag arcsec{sup -2}, confirming the results of Mihos et al., who saw a vast web of low surface brightness streams, arcs, plumes, and diffuse light in the Virgo cluster core using V-band imaging. By combining these two data sets, we are able to measure the optical colors of many of the cluster's low surface brightness features. While much of our imaging area is contaminated by galactic cirrus, the cluster core near the cD galaxy, M87, is unobscured. We trace the color profile of M87 out to over 2000'', and find a blueing trend with radius, continuing out to the largest radii. Moreover, we have measured the colors of several ICL features which extend beyond M87's outermost reaches and find that they have similar colors to the M87's halo itself, B - V {approx}0.8. The common colors of these features suggest that the extended outer envelopes of cD galaxies, such as M87, may be formed from similar streams, created by tidal interactions within the cluster, that have since dissolved into a smooth background in the cluster potential.

  9. Test of In-core Flux Detectors in KNK II

    E-Print Network [OSTI]

    Hoppe, P

    1979-01-01T23:59:59.000Z

    The development of in-core detectors for Liquid Metal Fast Breeder Reactors (LMFBRs) is still in an early stage, and little operation experience is available. Therefore self-powered neutron and gamma detectors and neutron sensitive ionization chambers -especially developed for LMFBRs- have been tested in the Fast Sodium Cooled Test Reactor KNK II. Seven flux detectors have been installed in the core of KNK II by means of a special test rig. Five of them failed already within the first week during operation in the reactor. Due to measurements of electrical resistances and capacities, sodium penetrating into the detectors or cables probably seems to be the cause. As tests prior to the installation in the core proved the tightness of all detectors, it is suspected that small cracks have developed in the detector casings or in the outer cable sheaths during their exposure to the hot coolant. Two ionization chambers did not show these faults. However, one of them failed because the saturation current plateau disap...

  10. Operations of a Radioisotope-based Propulsion System Enabling CubeSat Exploration of the Outer Planets

    SciTech Connect (OSTI)

    Dr. Steven Howe; Nathan Jerred; Troy Howe; Adarsh Rajguru

    2014-05-01T23:59:59.000Z

    Exploration to the outer planets is an ongoing endeavor but in the current economical environment, cost reduction is the forefront of all concern. The success of small satellites such as CubeSats launched to Near-Earth Orbit has lead to examine their potential use to achieve cheaper science for deep space applications. However, to achieve lower cost missions; hardware, launch and operations costs must be minimized. Additionally, as we push towards smaller exploration beds with relative limited power sources, allowing for adequate communication back to Earth is imperative. Researchers at the Center for Space Nuclear Research are developing the potential of utilizing an advanced, radioisotope-based system. This system will be capable of providing both the propulsion power needed to reach the destination and the additional requirements needed to maintain communication while at location. Presented here are a basic trajectory analysis, communication link budget and concept of operations of a dual-mode (thermal and electric) radioisotope-based propulsion system, for a proposed mission to Enceladus (Saturnian icy moon) using a 6U CubeSat payload. The radioisotope system being proposed will be the integration of three sub-systems working together to achieve the overall mission. At the core of the system, stored thermal energy from radioisotope decay is transferred to a passing propellant to achieve high thrust – useful for quick orbital maneuvering. An auxiliary closed-loop Brayton cycle can be operated in parallel to the thrusting mode to provide short bursts of high power for high data-rate communications back to Earth. Additionally, a thermal photovoltaic (TPV) energy conversion system will use radiation heat losses from the core. This in turn can provide the electrical energy needed to utilize the efficiency of ion propulsion to achieve quick interplanetary transit times. The intelligent operation to handle all functions of this system under optimized conditions adds to the complexity of the mission architecture.

  11. Electron Abundance in Protostellar Cores

    E-Print Network [OSTI]

    Paolo Padoan; Karen Willacy; William Langer; Mika Juvela

    2004-06-23T23:59:59.000Z

    The determination of the fractional electron abundance, Xe, in protostellar cores relies on observations of molecules, such as DCO+, H13CO+ and CO, and on chemical models to interpret their abundance. Studies of protostellar cores have revealed significant variations of Xe from core to core within a range 10^-8core age, extinction and density. We compute numerically the intensity of the radiation field within a density distribution generated by supersonic turbulence. Taking into account the lines of sight in all directions, the effective visual extinction in dense regions is found to be always much lower than the extinction derived from the column density along a fixed line of sight. Dense cores with volume and column densities comparable to observed protostellar cores have relatively low mass-averaged visual extinction, 2mag <= A_V <= 5mag, such that photo-ionization can sometimes be as important as cosmic ray ionization. Chemical models, including gas-grain chemistry and time dependent gas depletion and desorption, are computed for values of visual extinction in the range 2mag <= A_V <= 6mag, and for a hydrogen gas density of 10^4cm^-3$, typical of protostellar cores. The models presented here can reproduce some of the observed variations of ion abundance from core to core as the combined effect of visual extinction and age variations. The range of electron abundances predicted by the models is relatively insenstive to density over 10^4 to 10^6 cm^{-3}.

  12. Bent core liquid crystal elastomers

    SciTech Connect (OSTI)

    Verduzco, R.; DiMasi, E.; Luchette, P.; Ho Hong, S.; Harden, J.; Palffy-Muhoray, P.; Kilbey II, S.M.; Sprunt, S.; Gleeson, G.T. Jakli, A.

    2010-07-28T23:59:59.000Z

    Liquid crystal (LC) elastomers with bent-core side-groups incorporate the properties of bent-core liquid crystals in a flexible and self-supporting polymer network. Bent-core liquid crystal elastomers (BCEs) with uniform alignment were prepared by attaching a reactive bent-core LC to poly(hydrogenmethylsiloxane) and crosslinking with a divinyl crosslinker. Phase behavior studies indicate a nematic phase over a wide temperature range that approaches room temperature, and thermoelastic measurements show that these BCEs can reversibly change their length by more than a factor of two upon heating and cooling. Small-angle X-ray scattering studies reveal multiple, broad low-angle peaks consistent with short-range smectic C order of the bent-core side groups. A comparison of these patterns with predictions of a Landau model for short-range smectic C order shows that the length scale for smectic ordering in BCEs is similar to that seen in pure bent-core LCs. The combination of rubber elasticity and smectic ordering of the bent-core side groups suggests that BCEs may be promising materials for sensing, actuating, and other advanced applications.

  13. The great dichotomy of the Solar System: small terrestrial embryos and massive giant planet cores

    E-Print Network [OSTI]

    Morbidelli, A; Jacobson, S; Bitsch, B

    2015-01-01T23:59:59.000Z

    The basic structure of the solar system is set by the presence of low-mass terrestrial planets in its inner part and giant planets in its outer part. This is the result of the formation of a system of multiple embryos with approximately the mass of Mars in the inner disk and of a few multi-Earth-mass cores in the outer disk, within the lifetime of the gaseous component of the protoplanetary disk. What was the origin of this dichotomy in the mass distribution of embryos/cores? We show in this paper that the classic processes of runaway and oligarchic growth from a disk of planetesimals cannot explain this dichotomy, even if the original surface density of solids increased at the snowline. Instead, the accretion of drifting pebbles by embryos and cores can explain the dichotomy, provided that some assumptions hold true. We propose that the mass-flow of pebbles is two-times lower and the characteristic size of the pebbles is approximately ten times smaller within the snowline than beyond the snowline (respective...

  14. Preliminary engineering studies for the support shell of the outer tracker of the SDC detector

    SciTech Connect (OSTI)

    Vandergriff, D.H.; Mayhall, J.

    1991-09-01T23:59:59.000Z

    The Solenoidal Detector Collaboration (SDC) detector is in the conceptual design phase. ORNL is currently working with various sub-groups on the design of the outer tracker portion of the SDC detector. A major focus in the outer tracker design is the structure that mounts and supports the tracking elements. This structure must meet extreme requirements of alignment and stability while containing a minimum of material. This report describes the requirements, evaluations, and analyses that have been performed on the two options being explored; a cylindrical support shell and a modular support shell.

  15. The outer disks of galaxies: "To be or not to be truncated?"

    E-Print Network [OSTI]

    M. Pohlen; I. Trujillo

    2005-09-02T23:59:59.000Z

    We have in recent years come to view the outer parts of galaxies as having vital clues about their formation and evolution. Here, we would like to briefly present our results from a complete sample of nearby, late-type, spiral galaxies, using data from the SDSS survey, especially focused on the stellar light distribution in the outer disk. Our study shows that only the minority of late-type galaxies show a classical, exponential Freeman Type I profile down to the noise limit, whereas the majority exhibit either downbending (stellar truncation as introduced 1979 by Piet van der Kruit) or upbending profiles.

  16. Modeling the deep penetration of outer belt electrons during the ``Halloween'' magnetic storm in 2003

    E-Print Network [OSTI]

    Li, Xinlin

    of this model is that the inputs are solely from measurements of current solar wind and energetic electrons. During the geomagnetic storm of October/November 2003, the intensity peak of the outer radiation belt model is developed, using the measurements of relativistic electrons at geosynchronous orbit

  17. Evaluation of outer flaws in titanium alloys using eddy current measuring system

    SciTech Connect (OSTI)

    Chady, T.; Psuj, G.; Kowalczyk, J. [Department of Electrical and Computer Engineering, West Pomeranian University of Technology in Szczecin, ul. Sikorskiego 37, 70-313 Szczecin (Poland)

    2011-06-23T23:59:59.000Z

    In this paper results of shallow outer flaw detection in thick titanium alloy specimens is presented. In order to increase efficiency of inspections of minor defects an eddy current measuring system with a lock-in amplifier was used. The measurements were carried out for flat and cylindrical specimens with artificial flaws.

  18. Gas & Stars Aging low-mass stars eject their outer layers.

    E-Print Network [OSTI]

    Barnes, Joshua Edward

    Recycling Gas & Stars #12;Aging low-mass stars eject their outer layers. M57:The Ring Nebula #12;Thor's Emerald Helmet Winds from high-mass stars blow bubbles of hot gas. #12;Supernova blast waves in stars are mixed back into the gas. NGC 6992: Filaments of theVeil Nebula #12;Bubbles blown by high

  19. Atlantic update, July 1986--June 1990: Outer Continental Shelf oil and gas activities

    SciTech Connect (OSTI)

    Karpas, R.M.; Gould, G.J.

    1990-10-01T23:59:59.000Z

    This report describes outer continental shelf oil and gas activities in the Atlantic Region. This edition of the Atlantic Update includes an overview of the Mid-Atlantic Planning Area and a summary of the Manteo Prospect off-shore North Carolina. 6 figs., 8 tabs.

  20. Production and Pressure Decline Curves for Wet Gas Sands With Closed Outer Boundaries

    E-Print Network [OSTI]

    Mohaghegh, Shahab

    . SPE SPE 23442 Production and Pressure Decline Curves for Wet Gas Sands With Closed Outer, Richardson, TX 7S0834S36 U.5A. Telex, 730989 SPEDAL. ABSTRACT A family of pressure and production decline as gas reservoirs which produce substan- tial amounts of water together with ~as. Production of water

  1. Energetic outer radiation-belt electron precipitation during recurrent solar activity

    E-Print Network [OSTI]

    Otago, University of

    on the atmosphere [Seppälä et al., 2004]. During some intense solar storms solar protons in the energy range 1Energetic outer radiation-belt electron precipitation during recurrent solar activity Mark A and Physical Sciences, University of Newcastle, Callaghan, Australia. Russell S. Grew School of Mathematical

  2. Oxygen Transport from the Outer Boundary of a Pulsating Arteriole Wall to the

    E-Print Network [OSTI]

    Salamon, Peter

    Oxygen Transport from the Outer Boundary of a Pulsating Arteriole Wall to the Surrounding Tissue In all living organisms, oxygen transport from arterioles to the surrounding tissue is critical for survival. However, the exact nature of the transport of oxygen from the arteriole to the surrounding tissue

  3. Distribution and abundance of endangered Florida Key deer on outer islands

    E-Print Network [OSTI]

    Watts, Dominque Elijah

    2007-04-25T23:59:59.000Z

    parameters has limited status assessment and management of Key deer on outer islands. Traditional survey techniques for Key deer on Big Pine and No Name keys include road-counts, strip-counts, and mark-recapture methods. However, practical limitations render...

  4. Electron loss rates from the outer radiation belt caused by the filling of the outer plasmasphere: the calm before the storm

    SciTech Connect (OSTI)

    Borovsky, Joseph E [Los Alamos National Laboratory; Denton, Michael H [LANCASTER UNIV

    2009-01-01T23:59:59.000Z

    Measurements from 7 spacecraft in geosynchronous orbit are analyzed to determine the decay rate of the number density of the outer electron radiation belt prior to the onset of high-speed-stream-driven geomagnetic storms. Superposed-data analysis is used wan(?) a collection of 124 storms. When there is a calm before the storm, the electron number density decays exponentially before the storm with a 3.4-day e-folding time: beginning about 4 days before storm onset, the density decreases from {approx}4x10{sup -4} cm{sup -3} to {approx}1X 10{sup -4} cm{sup -3}. When there is not a calm before the storm, the number-density decay is very smalL The decay in the number density of radiation-belt electrons is believed to be caused by pitch-angle scattering of electrons into the atmospheric loss cone as the outer plasmasphere fills during the calms. While the radiation-belt electron density decreases, the temperature of the electron radiation belt holds approximately constant, indicating that the electron precipitation occurs equally at all energies. Along with the number density decay, the pressure of the outer electron radiation belt decays and the specific entropy increases. From the measured decay rates, the electron flux to the atmosphere is calculated and that flux is 3 orders of magnitude less than thermal fluxes in the magnetosphere, indicating that the radiation-belt pitch-angle scattering is 3 orders weaker than strong diffusion. Energy fluxes into the atmosphere are calculated and found to be insufficient to produce visible airglow.

  5. NON-EQUILIBRIUM CHEMISTRY OF DYNAMICALLY EVOLVING PRESTELLAR CORES. II. IONIZATION AND MAGNETIC FIELD

    SciTech Connect (OSTI)

    Tassis, Konstantinos; Willacy, Karen; Yorke, Harold W.; Turner, Neal J. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

    2012-07-20T23:59:59.000Z

    We study the effect that non-equilibrium chemistry in dynamical models of collapsing molecular cloud cores has on measurements of the magnetic field in these cores, the degree of ionization, and the mean molecular weight of ions. We find that OH and CN, usually used in Zeeman observations of the line-of-sight magnetic field, have an abundance that decreases toward the center of the core much faster than the density increases. As a result, Zeeman observations tend to sample the outer layers of the core and consistently underestimate the core magnetic field. The degree of ionization follows a complicated dependence on the number density at central densities up to 10{sup 5} cm{sup -3} for magnetic models and 10{sup 6} cm{sup -3} in non-magnetic models. At higher central densities, the scaling approaches a power law with a slope of -0.6 and a normalization which depends on the cosmic-ray ionization rate {zeta} and the temperature T as ({zeta}T){sup 1/2}. The mean molecular weight of ions is systematically lower than the usually assumed value of 20-30, and, at high densities, approaches a value of 3 due to the asymptotic dominance of the H{sup +}{sub 3} ion. This significantly lower value implies that ambipolar diffusion operates faster.

  6. Gelcasting Alumina Cores for Investment Casting

    SciTech Connect (OSTI)

    Janney, M A; Klug, F J

    2001-01-01T23:59:59.000Z

    General Electric currently uses silica investment casting cores for making superalloy turbine blades. The silica core technology does not provide the degree of dimensional control needed for advanced turbine system manufacture. The sum of the various process variables in silica core manufacturing produces cores that have more variability than is allowed for in advanced, power-generation gas turbine airfoils.

  7. Sequence stratigraphic-based reservoir architecture in late Jurrassic outer-ramp carbonates, Hanifa Formation, Saudi Arabia

    SciTech Connect (OSTI)

    Markello, J.R.; Stockton, M.L. (Mobile E P Technical Center, Dallas, TX (United States)); McGuire, M.; Al'Shammery, M.J.; Al'Amoudi M.O. (Saudi Aramco, Dhahran (Saudi Arabia))

    1996-01-01T23:59:59.000Z

    The Hanifa Formation (135-160m tk; Kimmeridgian age), in our study area, comprises one 3rd-order, coarsening-upward, type 2 stratigraphic sequence. Sediments formed in outer ramp, ramp-margin and basinal environments defining a transition between the Rimthan Arch carbonate platform and adjacent Arabian intrashelf basin. Quantification of Hanifa reservoir architecture for simulation involved development of field-scale geologic models based on sequence stratigraphic principles. No seismic and biostratigraphic data were available. Sequence interpretations were based on regional facies and parasequence analysis from 32 cores and 142 gamma-ray/porosity logs. In the study area, the Hanifa Formation has basinward-thinning tabular geometry, and contains (1) a lower member of organic-rich muddy carbonates and (2) an upper reservoir member of thick, medium to coarse-grained skeletal packstones, skeletal peloidal grainstones, skeletal intraclast conglomerates, and stromatoporoid boundstones. The Hanifa reservoir consists of, from oldest to youngest: (1) a highstand systems tract: aggrading and prograding, sigmoidal-shaped parasequences and parasequence sets of grainstrines, conglomerates and boundstones, capped by a subaqueous, type 2 sequence boundary; (2) a shelf margin wedge: prograding to aggrading, sigmoidal to tabular-shaped parasequences and parasequence sets of skeletal packstones, grainstones and local boundstones showing maximum basinward progradation; and (3) a transgressive systems tract: backstepping tabular-shaped parasequences of grainstones capped by a drowning surface. All facies are interpreted to have formed in subtidal settings of water depths from 5 to 150m. No evidence was found for shoal-water bank, lagoonal or peritidal deposition or for subaerial exposure in any facies.

  8. Sequence stratigraphic-based reservoir architecture in late Jurrassic outer-ramp carbonates, Hanifa Formation, Saudi Arabia

    SciTech Connect (OSTI)

    Markello, J.R.; Stockton, M.L. [Mobile E & P Technical Center, Dallas, TX (United States); McGuire, M.; Al`Shammery, M.J.; Al`Amoudi M.O. [Saudi Aramco, Dhahran (Saudi Arabia)

    1996-12-31T23:59:59.000Z

    The Hanifa Formation (135-160m tk; Kimmeridgian age), in our study area, comprises one 3rd-order, coarsening-upward, type 2 stratigraphic sequence. Sediments formed in outer ramp, ramp-margin and basinal environments defining a transition between the Rimthan Arch carbonate platform and adjacent Arabian intrashelf basin. Quantification of Hanifa reservoir architecture for simulation involved development of field-scale geologic models based on sequence stratigraphic principles. No seismic and biostratigraphic data were available. Sequence interpretations were based on regional facies and parasequence analysis from 32 cores and 142 gamma-ray/porosity logs. In the study area, the Hanifa Formation has basinward-thinning tabular geometry, and contains (1) a lower member of organic-rich muddy carbonates and (2) an upper reservoir member of thick, medium to coarse-grained skeletal packstones, skeletal peloidal grainstones, skeletal intraclast conglomerates, and stromatoporoid boundstones. The Hanifa reservoir consists of, from oldest to youngest: (1) a highstand systems tract: aggrading and prograding, sigmoidal-shaped parasequences and parasequence sets of grainstrines, conglomerates and boundstones, capped by a subaqueous, type 2 sequence boundary; (2) a shelf margin wedge: prograding to aggrading, sigmoidal to tabular-shaped parasequences and parasequence sets of skeletal packstones, grainstones and local boundstones showing maximum basinward progradation; and (3) a transgressive systems tract: backstepping tabular-shaped parasequences of grainstones capped by a drowning surface. All facies are interpreted to have formed in subtidal settings of water depths from 5 to 150m. No evidence was found for shoal-water bank, lagoonal or peritidal deposition or for subaerial exposure in any facies.

  9. Intrinsic Shapes of Molecular Cloud Cores

    E-Print Network [OSTI]

    C. E. Jones; Shantanu Basu; John Dubinski

    2001-01-08T23:59:59.000Z

    We conduct an analysis of the shapes of molecular cloud cores using recently compiled catalogs of observed axis ratios of individual cores mapped in ammonia or through optical selection. We apply both analytical and statistical techniques to deproject the observed axis ratios in order to determine the true distribution of cloud core shapes. We find that neither pure oblate nor pure prolate cores can account for the observed distribution of core shapes. Intrinsically triaxial cores produce distributions which agree with observations. The best-fit triaxial distribution contains cores which are more nearly oblate than prolate.

  10. Grain alignment in starless cores

    SciTech Connect (OSTI)

    Jones, T. J.; Bagley, M. [Minnesota Institute for Astrophysics, University of Minnesota, Minneapolis, MN 55455 (United States); Krejny, M. [Cree Inc., 4600 Silicon Dr., Durham, NC (United States); Andersson, B.-G. [SOFIA Science Center, USRA, Moffett Field, CA (United States); Bastien, P., E-mail: tjj@astro.umn.edu [Centre de recherche en astrophysique du Québec and Départment de Physique, Université de Montréal, Montréal (Canada)

    2015-01-01T23:59:59.000Z

    We present near-IR polarimetry data of background stars shining through a selection of starless cores taken in the K band, probing visual extinctions up to A{sub V}?48. We find that P{sub K}/?{sub K} continues to decline with increasing A{sub V} with a power law slope of roughly ?0.5. Examination of published submillimeter (submm) polarimetry of starless cores suggests that by A{sub V}?20 the slope for P versus ? becomes ??1, indicating no grain alignment at greater optical depths. Combining these two data sets, we find good evidence that, in the absence of a central illuminating source, the dust grains in dense molecular cloud cores with no internal radiation source cease to become aligned with the local magnetic field at optical depths greater than A{sub V}?20. A simple model relating the alignment efficiency to the optical depth into the cloud reproduces the observations well.

  11. Reactor core isolation cooling system

    DOE Patents [OSTI]

    Cooke, Franklin E. (San Jose, CA)

    1992-01-01T23:59:59.000Z

    A reactor core isolation cooling system includes a reactor pressure vessel containing a reactor core, a drywell vessel, a containment vessel, and an isolation pool containing an isolation condenser. A turbine is operatively joined to the pressure vessel outlet steamline and powers a pump operatively joined to the pressure vessel feedwater line. In operation, steam from the pressure vessel powers the turbine which in turn powers the pump to pump makeup water from a pool to the feedwater line into the pressure vessel for maintaining water level over the reactor core. Steam discharged from the turbine is channeled to the isolation condenser and is condensed therein. The resulting heat is discharged into the isolation pool and vented to the atmosphere outside the containment vessel for removing heat therefrom.

  12. Reactor core isolation cooling system

    DOE Patents [OSTI]

    Cooke, F.E.

    1992-12-08T23:59:59.000Z

    A reactor core isolation cooling system includes a reactor pressure vessel containing a reactor core, a drywell vessel, a containment vessel, and an isolation pool containing an isolation condenser. A turbine is operatively joined to the pressure vessel outlet steamline and powers a pump operatively joined to the pressure vessel feedwater line. In operation, steam from the pressure vessel powers the turbine which in turn powers the pump to pump makeup water from a pool to the feedwater line into the pressure vessel for maintaining water level over the reactor core. Steam discharged from the turbine is channeled to the isolation condenser and is condensed therein. The resulting heat is discharged into the isolation pool and vented to the atmosphere outside the containment vessel for removing heat therefrom. 1 figure.

  13. Core-melt source reduction system

    DOE Patents [OSTI]

    Forsberg, C.W.; Beahm, E.C.; Parker, G.W.

    1995-04-25T23:59:59.000Z

    A core-melt source reduction system for ending the progression of a molten core during a core-melt accident and resulting in a stable solid cool matrix. The system includes alternating layers of a core debris absorbing material and a barrier material. The core debris absorbing material serves to react with and absorb the molten core such that containment overpressurization and/or failure does not occur. The barrier material slows the progression of the molten core debris through the system such that the molten core has sufficient time to react with the core absorbing material. The system includes a provision for cooling the glass/molten core mass after the reaction such that a stable solid cool matrix results. 4 figs.

  14. Core-melt source reduction system

    DOE Patents [OSTI]

    Forsberg, Charles W. (Oak Ridge, TN); Beahm, Edward C. (Oak Ridge, TN); Parker, George W. (Concord, TN)

    1995-01-01T23:59:59.000Z

    A core-melt source reduction system for ending the progression of a molten core during a core-melt accident and resulting in a stable solid cool matrix. The system includes alternating layers of a core debris absorbing material and a barrier material. The core debris absorbing material serves to react with and absorb the molten core such that containment overpressurization and/or failure does not occur. The barrier material slows the progression of the molten core debris through the system such that the molten core has sufficient time to react with the core absorbing material. The system includes a provision for cooling the glass/molten core mass after the reaction such that a stable solid cool matrix results.

  15. Massive Quiescent Cores in Orion. -- II. Core Mass Function

    E-Print Network [OSTI]

    Li, D; Goldsmith, P F; Langer, W D

    2006-01-01T23:59:59.000Z

    We have surveyed submillimeter continuum emission from relatively quiescent regions in the Orion molecular cloud to determine how the core mass function in a high mass star forming region compares to the stellar initial mass function. Such studies are important for understanding the evolution of cores to stars, and for comparison to formation processes in high and low mass star forming regions. We used the SHARC II camera on the Caltech Submillimeter Observatory telescope to obtain 350 \\micron data having angular resolution of about 9 arcsec, which corresponds to 0.02 pc at the distance of Orion. Our analysis combining dust continuum and spectral line data defines a sample of 51 Orion molecular cores with masses ranging from 0.1 \\Ms to 46 \\Ms and a mean mass of 9.8 \\Ms, which is one order of magnitude higher than the value found in typical low mass star forming regions, such as Taurus. The majority of these cores cannot be supported by thermal pressure or turbulence, and are probably supercritical.They are th...

  16. Kansalliskirjasto Dublin Core Dublin Core metadataformaatin suomalainen versio

    E-Print Network [OSTI]

    Rodriguez, Carlos

    - Medical Subject Headings 3. DDC - Dewey Decimal Classification 4. LCC - Library of Congress Classification: - Merkintäjärjestelmät: #12;Kansalliskirjasto Dublin Core 2(6) 1. LCSH - Library of Congress Subject Headings 2. MESH 5. UDC - Universal Decimal Classification Suomalaiset merkintäjärjestelmät katso sfs_aihe.pdf Kuvaus

  17. Core Values | The Ames Laboratory

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power Administration would likeConstitution AndControllingCool MagneticCoos BayCore FileCore

  18. Laminated grid and web magnetic cores

    DOE Patents [OSTI]

    Sefko, John (Monroeville, PA); Pavlik, Norman M. (Plum Borough, PA)

    1984-01-01T23:59:59.000Z

    A laminated magnetic core characterized by an electromagnetic core having core legs which comprise elongated apertures and edge notches disposed transversely to the longitudinal axis of the legs, such as high reluctance cores with linear magnetization characteristics for high voltage shunt reactors. In one embodiment the apertures include compact bodies of microlaminations for more flexibility and control in adjusting permeability and/or core reluctance.

  19. Influence of core size on the upconversion luminescence properties of spherical Gd{sub 2}O{sub 3}:Yb{sup 3+}/Er{sup 3+}@SiO{sub 2} particles with core-shell structures

    SciTech Connect (OSTI)

    Zheng, Kezhi; Liu, Zhenyu; Liu, Ye; Song, Weiye; Qin, Weiping, E-mail: wpqin@jlu.edu.cn [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012 (China)

    2013-11-14T23:59:59.000Z

    Spherical SiO{sub 2} particles with different sizes (30, 80, 120, and 180?nm) have been coated with Gd{sub 2}O{sub 3}:Yb{sup 3+}/Er{sup 3+} layers by a heterogeneous precipitation method, leading to the formation of core-shell structural Gd{sub 2}O{sub 3}:Yb{sup 3+}/Er{sup 3+}@SiO{sub 2} particles. The samples were characterized by using X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, upconversion (UC) emission spectra, and fluorescent dynamical analysis. The obtained core-shell particles have perfect spherical shape with narrow size distribution. Under the excitation of 980?nm diode laser, the core-shell samples showed size-dependent upconversion luminescence (UCL) properties. The inner SiO{sub 2} cores in core-shell samples were proved to have limited effect on the total UCL intensities of Er{sup 3+} ions. The UCL intensities of core-shell particles were demonstrated much higher than the values obtained in pure Gd{sub 2}O{sub 3}:Yb{sup 3+}/Er{sup 3+} with the same phosphor volume. The dependence of the specific area of a UCL shell on the size of its inner SiO{sub 2} particle was calculated and analyzed for the first time. It was confirmed that the surface effect came from the outer surfaces of emitting shells is dominant in influencing the UCL property in the core-shell samples. Three-photon UC processes for the green emissions were observed in the samples with small sizes of SiO{sub 2} cores. The results of dynamical analysis illustrated that more nonradiative relaxation occurred in the core-shell samples with smaller SiO{sub 2} core sizes.

  20. Large core fiber optic cleaver

    DOE Patents [OSTI]

    Halpin, J.M.

    1996-03-26T23:59:59.000Z

    The present invention relates to a device and method for cleaving optical fibers which yields cleaved optical fiber ends possessing high damage threshold surfaces. The device can be used to cleave optical fibers with core diameters greater than 400 {micro}m. 30 figs.

  1. Large core fiber optic cleaver

    DOE Patents [OSTI]

    Halpin, John M. (Livermore, CA)

    1996-01-01T23:59:59.000Z

    The present invention relates to a device and method for cleaving optical fibers which yields cleaved optical fiber ends possessing high damage threshold surfaces. The device can be used to cleave optical fibers with core diameters greater than 400 .mu.m.

  2. Stability of Molten Core Materials

    SciTech Connect (OSTI)

    Layne Pincock; Wendell Hintze

    2013-01-01T23:59:59.000Z

    The purpose of this report is to document a literature and data search for data and information pertaining to the stability of nuclear reactor molten core materials. This includes data and analysis from TMI-2 fuel and INL’s LOFT (Loss of Fluid Test) reactor project and other sources.

  3. DISTRIBUTION COEFICIENTS (KD) GENERATED FROM A CORE SAMPLE COLLECTED FROM THE SALTSTONE DISPOSAL FACILITY

    SciTech Connect (OSTI)

    Almond, P.; Kaplan, D.

    2011-04-25T23:59:59.000Z

    Core samples originating from Vault 4, Cell E of the Saltstone Disposal Facility (SDF) were collected in September of 2008 (Hansen and Crawford 2009, Smith 2008) and sent to SRNL to measure chemical and physical properties of the material including visual uniformity, mineralogy, microstructure, density, porosity, distribution coefficients (K{sub d}), and chemical composition. Some data from these experiments have been reported (Cozzi and Duncan 2010). In this study, leaching experiments were conducted with a single core sample under conditions that are representative of saltstone performance. In separate experiments, reducing and oxidizing environments were targeted to obtain solubility and Kd values from the measurable species identified in the solid and aqueous leachate. This study was designed to provide insight into how readily species immobilized in saltstone will leach from the saltstone under oxidizing conditions simulating the edge of a saltstone monolith and under reducing conditions, targeting conditions within the saltstone monolith. Core samples were taken from saltstone poured in December of 2007 giving a cure time of nine months in the cell and a total of thirty months before leaching experiments began in June 2010. The saltstone from Vault 4, Cell E is comprised of blast furnace slag, class F fly ash, portland cement, and Deliquification, Dissolution, and Adjustment (DDA) Batch 2 salt solution. The salt solution was previously analyzed from a sample of Tank 50 salt solution and characterized in the 4QCY07 Waste Acceptance Criteria (WAC) report (Zeigler and Bibler 2009). Subsequent to Tank 50 analysis, additional solution was added to the tank solution from the Effluent Treatment Project as well as from inleakage from Tank 50 pump bearings (Cozzi and Duncan 2010). Core samples were taken from three locations and at three depths at each location using a two-inch diameter concrete coring bit (1-1, 1-2, 1-3; 2-1, 2-2, 2-3; 3-1, 3-2, 3-3) (Hansen and Crawford 2009). Leaching experiments were conducted with a section of core sample 3-2. All cores from location 3 were drilled without using water. Core sample 3-2 was drilled from approximately six inches to a depth of approximately 13 inches. Approximately six inches of the core was removed but it broke into two pieces during removal from the bit. At the time of drilling, core material appeared olive green in color (Smith 2008). The fact that the samples were cored as olive green and were received after storage with a gray outer layer is indicative that some oxidation had occurred prior to leaching studies.

  4. Logging-while-coring method and apparatus

    DOE Patents [OSTI]

    Goldberg, David S.; Myers, Gregory J.

    2007-01-30T23:59:59.000Z

    A method and apparatus for downhole coring while receiving logging-while-drilling tool data. The apparatus includes core collar and a retrievable core barrel. The retrievable core barrel receives core from a borehole which is sent to the surface for analysis via wireline and latching tool The core collar includes logging-while-drilling tools for the simultaneous measurement of formation properties during the core excavation process. Examples of logging-while-drilling tools include nuclear sensors, resistivity sensors, gamma ray sensors, and bit resistivity sensors. The disclosed method allows for precise core-log depth calibration and core orientation within a single borehole, and without at pipe trip, providing both time saving and unique scientific advantages.

  5. Logging-while-coring method and apparatus

    DOE Patents [OSTI]

    Goldberg, David S. (New York, NY); Myers, Gregory J. (Cornwall, NY)

    2007-11-13T23:59:59.000Z

    A method and apparatus for downhole coring while receiving logging-while-drilling tool data. The apparatus includes core collar and a retrievable core barrel. The retrievable core barrel receives core from a borehole which is sent to the surface for analysis via wireline and latching tool The core collar includes logging-while-drilling tools for the simultaneous measurement of formation properties during the core excavation process. Examples of logging-while-drilling tools include nuclear sensors, resistivity sensors, gamma ray sensors, and bit resistivity sensors. The disclosed method allows for precise core-log depth calibration and core orientation within a single borehole, and without at pipe trip, providing both time saving and unique scientific advantages.

  6. A note on the rigidity of marginally outer trapped 2-spheres

    E-Print Network [OSTI]

    Galloway, Gregory J

    2015-01-01T23:59:59.000Z

    As discussed in the paper, in a matter-filled spacetime, perhaps with positive cosmological constant, a stable marginally outer trapped 2-sphere must satisfy a certain area inquality. Namely, its area must be bounded above by $4\\pi/c$, where $c > 0$ is a lower bound on a natural energy momentum term. In this paper we consider the rigidity that results for stable, or weakly outermost, marginally outer trapped 2-spheres that achieve this upper bound on the area. The "canonical" dynamical horizon in Vaidya spacetime and certain spacelike hypersurfaces in Nariai spacetime provide illustrations of the main results. These results may be viewed as spacetime analogues of the rigidity results of Bray, Brendle and Neves [10] concerning area minimizing 2-spheres in Riemannian 3-manifolds with scalar curvature having positive lower bound.

  7. A density-temperature description of the outer electron radiation belt during geomagnetic storms

    SciTech Connect (OSTI)

    Borovsky, Joseph E [Los Alamos National Laboratory; Cayton, Thomas E [Los Alamos National Laboratory; Denton, Michael H [LANCASTER UNIV

    2009-01-01T23:59:59.000Z

    Electron flux measurements from 7 satellites in geosynchronous orbit from 1990-2007 are fit with relativistic bi-Maxwellians, yielding a number density n and temperature T description of the outer electron radiation belt. For 54.5 spacecraft years of measurements the median value ofn is 3.7x10-4 cm-3 and the median value ofT is 142 keY. General statistical properties of n, T, and the 1.1-1.5 MeV flux J are investigated, including local-time and solar-cycle dependencies. Using superposed-epoch analysis triggered on storm onset, the evolution of the outer electron radiation belt through high-speed-steam-driven storms is investigated. The number density decay during the calm before the storm is seen, relativistic-electron dropouts and recoveries from dropout are investigated, and the heating of the outer electron radiation belt during storms is examined. Using four different triggers (SSCs, southward-IMF CME sheaths, southward-IMF magnetic clouds, and minimum Dst), CME-driven storms are analyzed with superposed-epoch techniques. For CME-driven storms an absence of a density decay prior to storm onset is found, the compression of the outer electron radiation belt at time of SSC is analyzed, the number-density increase and temperature decrease during storm main phase is seen, and the increase in density and temperature during storm recovery phase is observed. Differences are found between the density-temperature and the flux descriptions, with more information for analysis being available in the density-temperature description.

  8. Wind induced circulation on the outer continental shelf of Texas, spring 1982 

    E-Print Network [OSTI]

    Beard, Daniel Walker

    1984-01-01T23:59:59.000Z

    in the record is offshore, to the southeast. On the 29th of March, in the wake of strong northeast winds, the current shifted to the west. In general, the westward direction was maintained throughout the deployment period. However, there was one occurrence... WIND INDUCED CIRCULATION ON THE OUTER CONTINENTAL SHELF OF TEXAS, SPRING 1982 A Thesis by DANIEL WALKER BEARD Submitted to the Graduate College of Texas AE M University in partial fulfillment of the requirements for the degree of MASTER...

  9. Self-actuated nuclear reactor shutdown system using induction pump to facilitate sensing of core coolant temperature

    DOE Patents [OSTI]

    Sievers, Robert K. (N. Huntingdon, PA); Cooper, Martin H. (Churchill, PA); Tupper, Robert B. (Greensburg, PA)

    1987-01-01T23:59:59.000Z

    A self-actuated shutdown system incorporated into a reactivity control assembly in a nuclear reactor includes pumping means for creating an auxiliary downward flow of a portion of the heated coolant exiting from the fuel assemblies disposed adjacent to the control assembly. The shutdown system includes a hollow tubular member which extends through the outlet of the control assembly top nozzle so as to define an outer annular flow channel through the top nozzle outlet separate from an inner flow channel for primary coolant flow through the control assembly. Also, a latching mechanism is disposed in an inner duct of the control assembly and is operable for holding absorber bundles in a raised position in the control assembly and for releasing them to drop them into the core of the reactor for shutdown purposes. The latching mechanism has an inner flow passage extending between and in flow communication with the absorber bundles and the inner flow channel of the top nozzle for accommodating primary coolant flow upwardly through the control assembly. Also, an outer flow passage separate from the inner flow passage extends through the latching mechanism between and in flow communication with the inner duct and the outer flow channel of the top nozzle for accommodating inflow of a portion of the heated coolant from the adjacent fuel assemblies. The latching mechanism contains a magnetic material sensitive to temperature and operable to cause mating or latching together of the components of the latching mechanism when the temperature sensed is below a known temperature and unmating or unlatching thereof when the temperature sensed is above a given temperature. The temperature sensitive magnetic material is positioned in communication with the heated coolant flow through the outer flow passage for directly sensing the temperature thereof. Finally, the pumping means includes a jet induction pump nozzle and diffuser disposed adjacent the bottom nozzle of the control assembly and in flow communication with the inlet thereof. The pump nozzle is operable to create an upward driving flow of primary coolant through the pump diffuser and then to the absorber bundles. The upward driving flow of primary coolant, in turn, creates a suction head within the outer flow channel of the top nozzle and thereby an auxiliary downward flow of the heated coolant portion exiting from the upper end of the adjacent fuel assemblies through the outer flow channel to the pump nozzle via the outer flow passage of the latching mechanism and an annular space between the outer and inner spaced ducts of the control assembly housing. The temperature of the heated coolant exiting from the adjacent fuel assemblies can thereby be sensed directly by the temperature sensitive magnetic material in the latching mechanism.

  10. Westinghouse Fuel Assemblies Performance after Operation in South-Ukraine NPP Mixed Core

    SciTech Connect (OSTI)

    Abdullayev, A. M.; Kulish, G. V.; Slyeptsov, O.; Slyeptsov, S.; Aleshin, Y.; Sparrow, S.; Lashevych, P.; Sokolov, D.; Latorre, Richard

    2013-09-14T23:59:59.000Z

    The evaluation of WWER-1000 Westinghouse fuel performance was done using the results of post–irradiation examinations of six LTAs and the WFA reload batches that have operated normally in mixed cores at South-Ukraine NPP, Unit-3 and Unit-2. The data on WFA/LTA elongation, FR growth and bow, WFA bow and twist, RCCA drag force and drag work, RCCA drop time, FR cladding integrity as well as the visual observation of fuel assemblies obtained during the 2006-2012 outages was utilized. The analysis of the measured data showed that assembly growth, FR bow, irradiation growth, and Zr-1%Nb grid and ZIRLO cladding corrosion lies within the design limits. The RCCA drop time measured for the LTA/WFA is about 1.9 s at BOC and practically does not change at EOC. The measured WFA bow and twist, and data of drag work on RCCA insertion showed that the WFA deformation in the mixed core is mostly controlled by the distortion of Russian FAs (TVSA) having the higher lateral stiffness. The visual inspection of WFAs carried out during the 2012 outages revealed some damage to the Zr-1%Nb grid outer strap for some WFAs during the loading sequence. The performed fundamental investigations allowed identifying the root cause of grid outer strap deformation and proposing the WFA design modifications for preventing damage to SG at a 225 kg handling trip limit.

  11. DETECTING THE RAPIDLY EXPANDING OUTER SHELL OF THE CRAB NEBULA: WHERE TO LOOK

    SciTech Connect (OSTI)

    Wang Xiang; Ferland, G. J. [Department of Physics and Astronomy, University of Kentucky, Lexington, KY 40506 (United States); Baldwin, J. A.; Loh, E. D.; Richardson, C. T., E-mail: xiang.wang@uky.edu [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824-2320 (United States)

    2013-09-10T23:59:59.000Z

    We present a range of steady-state photoionization simulations, corresponding to different assumed shell geometries and compositions, of the unseen postulated rapidly expanding outer shell to the Crab Nebula. The properties of the shell are constrained by the mass that must lie within it, and by limits to the intensities of hydrogen recombination lines. In all cases the photoionization models predict very strong emissions from high ionization lines that will not be emitted by the Crab's filaments, alleviating problems with detecting these lines in the presence of light scattered from brighter parts of the Crab. The near-NIR [Ne VI] {lambda}7.652 {mu}m line is a particularly good case; it should be dramatically brighter than the optical lines commonly used in searches. The C IV {lambda}1549 doublet is predicted to be the strongest absorption line from the shell, which is in agreement with Hubble Space Telescope observations. We show that the cooling timescale for the outer shell is much longer than the age of the Crab, due to the low density. This means that the temperature of the shell will actually ''remember'' its initial conditions. However, the recombination time is much shorter than the age of the Crab, so the predicted level of ionization should approximate the real ionization. In any case, it is clear that IR observations present the best opportunity to detect the outer shell and so guide future models that will constrain early events in the original explosion.

  12. Extended core for motor/generator

    DOE Patents [OSTI]

    Shoykhet, Boris A.

    2005-05-10T23:59:59.000Z

    An extended stator core in a motor/generator can be utilized to mitigate losses in end regions of the core and a frame of the motor/generator. To mitigate the losses, the stator core can be extended to a length substantially equivalent to or greater than a length of a magnetically active portion in the rotor. Alternatively, a conventional length stator core can be utilized with a shortened magnetically active portion to mitigate losses in the motor/generator. To mitigate the losses in the core caused by stator winding, the core can be extended to a length substantially equivalent or greater than a length of stator winding.

  13. Extended core for motor/generator

    DOE Patents [OSTI]

    Shoykhet, Boris A.

    2006-08-22T23:59:59.000Z

    An extended stator core in a motor/generator can be utilized to mitigate losses in end regions of the core and a frame of the motor/generator. To mitigate the losses, the stator core can be extended to a length substantially equivalent to or greater than a length of a magnetically active portion in the rotor. Alternatively, a conventional length stator core can be utilized with a shortened magnetically active portion to mitigate losses in the motor/generator. To mitigate the losses in the core caused by stator winding, the core can be extended to a length substantially equivalent or greater than a length of stator winding.

  14. Failure of a neutrino-driven explosion after core-collapse may lead to a thermonuclear supernova

    E-Print Network [OSTI]

    Kushnir, Doron

    2014-01-01T23:59:59.000Z

    We demonstrate that $\\sim10$ seconds after core-collapse of a massive star, a thermonuclear explosion of the outer shells is possible for some (tuned) initial density and composition profiles, assuming the neutrinos failed to explode the star. The explosion may lead to a successful supernova, as first suggested by Burbidge, Burbidge, Fowler and Hoyle (1957). We perform a series of one-dimensional (1D) calculations of collapsing massive stars with simplified initial density profiles (similar to the results of stellar evolution calculations) and various compositions (not similar to 1D stellar evolution calculations). We assume that the neutrinos escaped with negligible effect on the outer layers, which inevitably collapse. As the shells collapse, they compress and heat up adiabatically, enhancing the rate of thermonuclear burning. In some cases, where significant shells of mixed helium and oxygen are present with pre-collapsed burning times of $\\lesssim100\\,\\textrm{s}$ ($\\approx10$ times the free-fall time), a ...

  15. EARLY EVOLUTION OF PRESTELLAR CORES

    SciTech Connect (OSTI)

    Horedt, G. P., E-mail: g.horedt@online.de [Kronwinkler 50, D-81245, Munich (Germany)

    2013-08-20T23:59:59.000Z

    Prestellar cores are approximated by singular polytropic spheres. Their early evolution is studied analytically with a Bondi-like scheme. The considered approximation is meaningful for polytropic exponents {gamma} between 0 and 6/5, implying radial power-law density profiles between r {sup -1} and r {sup -2.5}. Gravitationally unstable Jeans and Bonnor-Ebert masses differ at most by a factor of 3.25. Tidally stable prestellar cores must have a mean density contrast {approx}> 8 with respect to the external parent cloud medium. The mass-accretion rate relates to the cube of equivalent sound speed, as in Shu's seminal paper. The prestellar masses accreted over 10{sup 5} years cover the whole stellar mass spectrum; they are derived in simple closed form, depending only on the polytropic equation of state. The stellar masses that can be formed via strict conservation of angular momentum are at most of the order of a brown dwarf.

  16. Processing of Activated Core Components

    SciTech Connect (OSTI)

    Friske, A.; Gestermann, G.; Finkbeiner, R.

    2003-02-26T23:59:59.000Z

    Used activated components from the core of a NPP like control elements, water channels from a BWR, and others like in-core measurement devices need to be processed into waste forms suitable for interim storage, and for the final waste repository. Processing of the activated materials can be undertaken by underwater cutting and packaging or by cutting and high-pressure compaction in a hot cell. A hot cell is available in Germany as a joint investment between GNS and the Karlsruhe Research Center at the latter's site. Special transport equipment is available to transport the components ''as-is'' to the hot cell. Newly designed underwater processing equipment has been designed, constructed, and operated for the special application of NPP decommissioning. This equipment integrates an underwater cutting device with an 80 ton force underwater in-drum compactor.

  17. TMI-2 core shipping preparations

    SciTech Connect (OSTI)

    Ball, L.J.; (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Barkanic, R.J. (Bechtel North American Power Corporation (United States)); Conaway, W.T. II (GPU Nuclear Corporation, Three Mile Island, Middletown, PA (United States)); Schmoker, D.S. (Nuclear Packaging, Inc., Federal Way, WA (United States))

    1988-01-01T23:59:59.000Z

    Shipping the damaged core from the Unit 2 reactor of Three Mile Island Nuclear Power Station near Harrisburg, PA, to the Idaho National Engineering Laboratory near Idaho Falls, ID, required development and implementation of a completely new spent fuel transportation system. This paper describes the equipment developed, the planning and activities used to implement the hardware systems into the facilities, and the planning involved in making the rail shipments. It also includes a summary of recommendations resulting from this experience.

  18. False Vacuum Lumps with the Fermionic Core

    E-Print Network [OSTI]

    Yutaka Hosotani; Ramin G. Daghigh

    2004-01-30T23:59:59.000Z

    Stable gravitating lumps with a false vacuum core surrounded by the true vacuum in a scalar field potential exist in the presence of fermions at the core. These objects may exist in the universe at various scales.

  19. Scaling Turbo Boost to a 1000 cores

    E-Print Network [OSTI]

    S, Ananth Narayan; Fedorova, Alexandra

    2010-01-01T23:59:59.000Z

    The Intel Core i7 processor code named Nehalem provides a feature named Turbo Boost which opportunistically varies the frequencies of the processor's cores. The frequency of a core is determined by core temperature, the number of active cores, the estimated power consumption, the estimated current consumption, and operating system frequency scaling requests. For a chip multi-processor(CMP) that has a small number of physical cores and a small set of performance states, deciding the Turbo Boost frequency to use on a given core might not be difficult. However, we do not know the complexity of this decision making process in the context of a large number of cores, scaling to the 100s, as predicted by researchers in the field.

  20. Coring in deep hardrock formations

    SciTech Connect (OSTI)

    Drumheller, D.S.

    1988-08-01T23:59:59.000Z

    The United States Department of Energy is involved in a variety of scientific and engineering feasibility studies requiring extensive drilling in hard crystalline rock. In many cases well depths extend from 6000 to 20,000 feet in high-temperature, granitic formations. Examples of such projects are the Hot Dry Rock well system at Fenton Hill, New Mexico and the planned exploratory magma well near Mammoth Lakes, California. In addition to these programs, there is also continuing interest in supporting programs to reduce drilling costs associated with the production of geothermal energy from underground sources such as the Geysers area near San Francisco, California. The overall progression in these efforts is to drill deeper holes in higher temperature, harder formations. In conjunction with this trend is a desire to improve the capability to recover geological information. Spot coring and continuous coring are important elements in this effort. It is the purpose of this report to examine the current methods used to obtain core from deep wells and to suggest projects which will improve existing capabilities. 28 refs., 8 figs., 2 tabs.

  1. Granular Dynamics in Pebble Bed Reactor Cores

    E-Print Network [OSTI]

    Laufer, Michael Robert

    2013-01-01T23:59:59.000Z

    a simulant fluid to match the dynamics of fuel pebbles andfuel pebbles through reactor cores with and without coupled fluid

  2. FISSION REACTORS KEYWORDS: core-barrel vibra-

    E-Print Network [OSTI]

    Demazière, Christophe

    FISSION REACTORS KEYWORDS: core-barrel vibra- tions, in-core neutron noise, shell- mode vibrations CALCULATION OF THE NEUTRON NOISE INDUCED BY SHELL-MODE CORE-BARREL VIBRATIONS IN A 1-D, TWO-GROUP, TWO-REGION SLAB REACTOR MODEL CARL SUNDE,* CHRISTOPHE DEMAZI�RE, and IMRE PÁZSIT Chalmers University of Technology

  3. UW-Milwaukee Strategic Planning Core Team

    E-Print Network [OSTI]

    Saldin, Dilano

    UW-Milwaukee Strategic Planning Core Team MINUTES November 19, 2012 Regents Room, Chapman Hall, 10 Strategic Planning Core team with oversight, coordination, and providing campus leadership with strategic strategic planning framework. c. Distinguished Core Team from Operational teams (Functional and Thematic). 4

  4. Surface tension of the core-crust interface of neutron stars with global charge neutrality

    E-Print Network [OSTI]

    Jorge A. Rueda; Remo Ruffini; Yuan-Bin Wu; She-Sheng Xue

    2014-03-19T23:59:59.000Z

    It has been shown recently that taking into account strong, weak, electromagnetic, and gravitational interactions, and fulfilling the global charge neutrality of the system, a transition layer will happen between the core and crust of neutron stars, at the nuclear saturation density. We use relativistic mean field theory together with the Thomas-Fermi approximation to study the detailed structure of this transition layer and calculate its surface and Coulomb energy. We find that the surface tension is proportional to a power-law function of the baryon number density in the core bulk region. We also analyze the influence of the electron component and the gravitational field on the structure of the transition layer and the value of the surface tension to compare and contrast with known phenomenological results in nuclear physics. Based on the above results we study the instability against Bohr-Wheeler surface deformations in the case of neutron stars obeying global charge neutrality. Assuming the core-crust transition at nuclear density $\\rho_{core}\\approx 2.7 * 10^{14}$ g cm$^{-3}$, we find that the instability sets the upper limit to the crust density, $\\rho_{crust}^{crit}\\approx 1.2 * 10^{14}$ g cm$^{-3}$. This result implies a nonzero lower limit to the maximum electric field of the core-crust transition surface and makes inaccessible a limit of quasilocal charge neutrality in the limit $\\rho_{crust}=\\rho_{core}$. The general framework presented here can be also applied to study the stability of sharp phase transitions in hybrid stars as well as in strange stars, both bare and with outer crust. The results of this work open the way to a more general analysis of the stability of these transition surfaces, accounting for other effects such as gravitational binding, centrifugal repulsion, magnetic field induced by rotating electric field, and therefore magnetic dipole-dipole interactions.

  5. Development and exploration of the core-corona model of imploding plasma loads. Final report, 5 February 1979-5 March 1980

    SciTech Connect (OSTI)

    Guillory, J.; Terry, R.

    1980-07-01T23:59:59.000Z

    This program has as its primary objective the quantitative exploration and generalization of the core-corona model of imploding plasma load dynamics in close collaboration with radiation physics and modeling work. As a qualitative summary, one may say that the core-corona model arises from four physical considerations, all interrelated. The first assumption is that of a sharp density falloff in the outer regions of the annular plasma load. The transition region between the dense core plasma and the halo of corona plasma surrounding it is associated with a change from classical to anomalous resistivity, due to the onset of marginally stable microturbulence in the low density corona plasma. The second assumption is that the high-density annular wire/plasma core stops a penetrating coronal electron in distances short compared to the core dimensions, so that the coronal heating can couple to the core and soften the implosion. However, it is important to note that coronal electrons will not tend to execute straight orbits into the core, due to the large magnetic fields in the current carrying zone on the core surface. A third ingredient in the core/corona equation is an isothermal corona, and for this one must assume the corona to be sufficiently limited in space that equilibration to an isothermal pressure balance can be established rapidly as the core annulus implodes. The corona continuously re-established its pressure balance as the transition interface moves inward. The final constraint in the original core-corona model equations was that of quasi-static heat balance between ohmic heating in the corona, net deposition of hot electron energy into the core, and coronal radiative losses.

  6. Apparatus and methods for installing, removing and adjusting an inner turbine shell section relative to an outer turbine shell section

    DOE Patents [OSTI]

    Leach, David (Niskayuna, NY); Bergendahl, Peter Allen (Scotia, NY); Waldo, Stuart Forrest (Salem, NC); Smith, Robert Leroy (Milford, OH); Phelps, Robert Kim (Milford, OH)

    2001-01-01T23:59:59.000Z

    A turbine includes upper and lower inner shell sections mounting the nozzles and shrouds and which inner shell is supported by pins secured to a surrounding outer shell. To disassemble the turbine for access to the inner shell sections and rotor, an alignment fixture is secured to the lower outer shell section and has pins engaging the inner shell section. To disassemble the turbine, the inner shell weight is transferred to the lower outer shell section via the alignment fixture and cradle pins. Roller assemblies are inserted through access openings vacated by support pins to permit rotation of the lower inner shell section out of and into the lower outer shell section during disassembly and assembly. The alignment fixture includes adjusting rods for adjusting the inner shell axially, vertically, laterally and about a lateral axis. A roller over-cage is provided to rotate the inner shell and a dummy shell to facilitate assembly and disassembly in the field.

  7. Use of X-ray Absorption Spectroscopy to Distinguish Between Inner And Outer-sphere Pb Adsorption Complexes on Montmorillonite

    E-Print Network [OSTI]

    Sparks, Donald L.

    Use of X-ray Absorption Spectroscopy to Distinguish Between Inner And Outer-sphere Pb Adsorption on the functional groups at the edges of the montmorillonite. At I = 0.002 M Pb absorption was less dependent

  8. Particle trap to sheath non-binding contact for a gas-insulated transmission line having a corrugated outer conductor

    DOE Patents [OSTI]

    Fischer, William H. (Pittsburgh, PA)

    1984-04-24T23:59:59.000Z

    A non-binding particle trap to outer sheath contact for use in gas insulated transmission lines having a corrugated outer conductor. The non-binding feature of the contact according to the teachings of the invention is accomplished by having a lever arm rotatably attached to a particle trap by a pivot support axis disposed parallel to the direction of travel of the inner conductor/insulator/particle trap assembly.

  9. The Expulsion of Stellar Envelopes in Core-Collapse Supernovae

    E-Print Network [OSTI]

    Christopher D. Matzner; Christopher F. McKee

    1998-07-04T23:59:59.000Z

    We examine the relation between presupernova stellar structure and the distribution of ejecta in core-collapse supernovae, assuming adiabatic, spherically symmetric flow. We develop a simple yet accurate formula for the blastwave shock velocity, and demonstrate that the entire final density distribution can be approximated with simple models for the final pressure distribution, along with the approximate shock-deposited entropy, in a way that matches the results of simulations. We find that the distribution of density in a star's ejecta depends on whether its outer envelope is radiative or convective, and if convective, on the composition structure of the star; simple approximate forms are presented for red and blue supergiant ejecta. Our models are most accurate for the high-velocity ejecta from the periphery of a star, where the shock dynamics are predictable. We present formulae for the final density distribution of this material, for both radiative and efficiently convective envelopes. These formulae limit to the well-known planar, self-similar solutions for mass shells approaching the stellar surface. But, the assumption of adiabatic flow fails at low optical depth, so this planar limit need not be attained. Formulae are given for the observable properties of the X-ray burst accompanying shock emergence, and their dependence on the parameters of the explosion. Motivated by the relativistic expansion recently inferred by Kulkarni et al. (1998) for the synchrotron shell around SN1998bw, we estimate the criterion for relativistic mass ejection and the rest mass of relativistic ejecta.

  10. Generator stator core vent duct spacer posts

    DOE Patents [OSTI]

    Griffith, John Wesley (Schenectady, NY); Tong, Wei (Clifton Park, NY)

    2003-06-24T23:59:59.000Z

    Generator stator cores are constructed by stacking many layers of magnetic laminations. Ventilation ducts may be inserted between these layers by inserting spacers into the core stack. The ventilation ducts allow for the passage of cooling gas through the core during operation. The spacers or spacer posts are positioned between groups of the magnetic laminations to define the ventilation ducts. The spacer posts are secured with longitudinal axes thereof substantially parallel to the core axis. With this structure, core tightness can be assured while maximizing ventilation duct cross section for gas flow and minimizing magnetic loss in the spacers.

  11. An Outer Planet Beyond Pluto and Origin of the Trans-Neptunian Belt Architecture

    E-Print Network [OSTI]

    Patryk Sofia Lykawka; Tadashi Mukai

    2007-12-13T23:59:59.000Z

    Trans-Neptunian objects (TNOs) are remnants of a collisionally and dynamically evolved planetesimal disk in the outer solar system. This complex structure, known as the trans-Neptunian belt (or Edgeworth-Kuiper belt), can reveal important clues about disk properties, planet formation, and other evolutionary processes. In contrast to the predictions of accretion theory, TNOs exhibit surprisingly large eccentricities, e, and inclinations, i, which can be grouped into distinct dynamical classes. Several models have addressed the origin and orbital evolution of TNOs, but none have reproduced detailed observations, e.g., all dynamical classes and peculiar objects, or provided insightful predictions. Based on extensive simulations of planetesimal disks with the presence of the four giant planets and massive planetesimals, we propose that the orbital history of an outer planet with tenths of Earth's mass can explain the trans-Neptunian belt orbital structure. This massive body was likely scattered by one of the giant planets, which then stirred the primordial planetesimal disk to the levels observed at 40-50 AU and truncated it at about 48 AU before planet migration. The outer planet later acquired an inclined stable orbit (>100 AU; 20-40 deg) because of a resonant interaction with Neptune (an r:1 or r:2 resonance possibly coupled with the Kozai mechanism), guaranteeing the stability of the trans-Neptunian belt. Our model consistently reproduces the main features of each dynamical class with unprecedented detail; it also satisfies other constraints such as the current small total mass of the trans-Neptunian belt and Neptune's current orbit at 30.1 AU. We also provide observationally testable predictions.

  12. Core Competencies | Department of Energy

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 1112011AT&T, Inc.'sEnergyTexas1.SpaceFluorControlsEnergy Copy of FINAL SG DemoCore

  13. Core Universities | ornl.gov

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power Administration would likeConstitution AndControllingCool MagneticCoos BayCore File

  14. Core Holes | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand JumpConceptual Model, clickInformationNew|Core Analysis At Geysers| Open EnergyAl., 1987) | Open

  15. Core Analysis | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty EditCalifornia:PowerCER.pngRoofs and Heat Islands Jump|Information Dobson, EtCore

  16. The core legion object model

    SciTech Connect (OSTI)

    Lewis, M.; Grimshaw, A. [Univ. of Virginia, Charlottesville, VA (United States)

    1996-12-31T23:59:59.000Z

    The Legion project at the University of Virginia is an architecture for designing and building system services that provide the illusion of a single virtual machine to users, a virtual machine that provides secure shared object and shared name spaces, application adjustable fault-tolerance, improved response time, and greater throughput. Legion targets wide area assemblies of workstations, supercomputers, and parallel supercomputers, Legion tackles problems not solved by existing workstation based parallel processing tools; the system will enable fault-tolerance, wide area parallel processing, inter-operability, heterogeneity, a single global name space, protection, security, efficient scheduling, and comprehensive resource management. This paper describes the core Legion object model, which specifies the composition and functionality of Legion`s core objects-those objects that cooperate to create, locate, manage, and remove objects in the Legion system. The object model facilitates a flexible extensible implementation, provides a single global name space, grants site autonomy to participating organizations, and scales to millions of sites and trillions of objects.

  17. New Opportunities for Outer Solar System Science using Radioisotope Electric Propulsion

    SciTech Connect (OSTI)

    Noble, Robert J.; /SLAC; Amini, Rashied; Beauchamp, Patricia M.; /Caltech, JPL; Bennett, Gary L.; /Metaspace Enterprises; Brophy, John R.; Buratti, Bonnie J.; Ervin, Joan; /Caltech, JPL; Fernandez, Yan R.; /Central Florida U.; Grundy, Will; /Lowell Observ.; Khan, Mohammed Omair; /Caltech, JPL; King, David Q.; /Aerojet; Lang, Jared; /Caltech, JPL; Meech, Karen J.; /Hawaii U.; Newhouse, Alan; Oleson, Steven R.; Schmidt, George R.; /GRC; Spilker, Thomas; West, John L.; /Caltech, JPL; ,

    2010-05-26T23:59:59.000Z

    Today, our questions and hypotheses about the Solar System's origin have surpassed our ability to deliver scientific instruments to deep space. The moons of the outer planets, the Trojan and Centaur minor planets, the trans-Neptunian objects (TNO), and distant Kuiper Belt objects (KBO) hold a wealth of information about the primordial conditions that led to the formation of our Solar System. Robotic missions to these objects are needed to make the discoveries, but the lack of deep-space propulsion is impeding this science. Radioisotope electric propulsion (REP) will revolutionize the way we do deep-space planetary science with robotic vehicles, giving them unprecedented mobility. Radioisotope electric generators and lightweight ion thrusters are being developed today which will make possible REP systems with specific power in the range of 5 to 10 W/kg. Studies have shown that this specific power range is sufficient to perform fast rendezvous missions from Earth to the outer Solar System and fast sample return missions. This whitepaper discusses how mobility provided by REP opens up entirely new science opportunities for robotic missions to distant primitive bodies. We also give an overview of REP technology developments and the required next steps to realize REP.

  18. Magnetic Untwisting in Solar Jets that Go into the Outer Corona in Polar Coronal Holes

    E-Print Network [OSTI]

    Moore, Ronald L; Falconer, David A

    2015-01-01T23:59:59.000Z

    We study 14 large solar jets observed in polar coronal holes. In EUV movies from SDO/AIA, each jet appears similar to most X-ray jets and EUV jets that erupt in coronal holes, but each is exceptional in that it goes higher than most, so high that it is observed in the outer corona beyond 2.2 RSun in images from the SOHO/LASCO/C2 coronagraph. From AIA He II 304 {\\AA} movies and LASCO/C2 running-difference images of these high-reaching jets, we find: (1) the front of the jet transits the corona below 2.2 RSun at a speed typically several times the sound speed; (2) each jet displays an exceptionally large amount of spin as it erupts; (3) in the outer corona, most of the jets display measureable swaying and bending of a few degrees in amplitude; in three jets the swaying is discernibly oscillatory with a period of order 1 hour. These characteristics suggest that the driver in these jets is a magnetic-untwisting wave that is basically a large-amplitude (i.e., non-linear) torsional Alfven wave that is put into the ...

  19. The Roles of Outer Membrane Cytochromes of Shewanella and Geobacter in Extracellular Electron Transfer

    SciTech Connect (OSTI)

    Shi, Liang; Richardson, David; Wang, Zheming; Kerisit, Sebastien N.; Rosso, Kevin M.; Zachara, John M.; Fredrickson, Jim K.

    2009-08-01T23:59:59.000Z

    As key components of the electron transfer (ET) pathways used for dissimilatory reduction of solid iron [Fe(III)] and manganese [Mn(IV)] (hydr)oxides, outer membrane cytochromes MtrC and OmcA of Shewanella oneidensis MR-1 and OmcE and OmcS of Geobacter sulfurreducens mediate ET reactions extracellularly. Cell surface-exposed MtrC and OmcA can transfer electrons directly to the metal oxides. S. oneidensis MR-1 cells also secrete flavins that can facilitate ET to the oxides. The secreted flavins are thought to serve either as chelators that form soluble Fe(III)/Mn(IV)-flavin complexes or as electron shuttles that ferry the electrons from cell-associated ET proteins to the metal oxides. Cell-surface localization may also permit MtrC and OmcA to transfer electrons extracellularly to either flavin-chelated Fe(III)/Mn(IV) or oxidized flavins. OmcE and OmcS are proposed to be located on the Geobacter cell surface where they are believed to function as the intermediates to relay electrons to type IV pili, which are then hypothesized to transfer electrons directly to the metal oxides. Thus, cell surface-localization positions these outer membrane cytochromes to transfer electrons to Fe(III)/Mn(IV) oxides external to the bacterial cells either directly, indirectly, or both, demonstrating a common strategy shared by Shewanella and Geobacter for extracellular reduction of the oxides.

  20. Examining the specific entropy (density of adiabatic invariants) of the outer electron radiation belt

    SciTech Connect (OSTI)

    Borovsky, Joseph E [Los Alamos National Laboratory; Denton, Michael H [LANCASTER UNIV

    2008-01-01T23:59:59.000Z

    Using temperature and number-density measurements of the energetic-electron population from multiple spacecraft in geosynchronous orbit, the specific entropy S = T/n{sup 2/3} of the outer electron radiation belt is calculated. Then 955,527 half-hour-long data intervals are statistically analyzed. Local-time and solar-cycle variations in S are examined. The median value of the specific entropy (2.8 x 10{sup 7} eVcm{sup 2}) is much larger than the specific entropy of other particle populations in and around the magnetosphere. The evolution of the specific entropy through high-speed-stream-driven geomagnetic storms and through magnetic-cloud-driven geomagnetic storms is studied using superposed-epoch analysis. For high-speed-stream-driven storms, systematic variations in the entropy associated with electron loss and gain and with radiation-belt heating are observed in the various storm phases. For magnetic-cloud-driven storms, multiple trigger choices for the data superpositions reveal the effects of interplanetary shock arrival, sheath driving, cloud driving, and recovery phase. The specific entropy S = T/n{sup 2/3} is algebraically expressed in terms of the first and second adiabatic invariants of the electrons: this allows a relativistic expression for S in terms of T and n to be derived. For the outer electron radiation belt at geosynchronous orbit, the relativistic corrections to the specific entropy expression are -15%.

  1. The Nature of Blue Cores in Spheroids: a Possible Connection with AGN and Star Formation

    E-Print Network [OSTI]

    Felipe Menanteau; Andre R. Martel; Paolo Tozzi; Brenda Frye; Holland C. Ford; Leopoldo Infante; Narciso Benitez; Gaspar Galaz; Daniel Coe; Garth D. Illingworth; George F. Hartig; Marc Clampin

    2004-11-04T23:59:59.000Z

    We investigate the physical nature of blue cores in early-type galaxies through the first multi-wavelength analysis of a serendipitously discovered field blue-nucleated spheroid in the background of the deep ACS/WFC griz multicolor observations of the cluster Abell 1689. The resolved g-r, r-i and i-z color maps reveal a prominent blue core identifying this galaxy as a ``typical'' case study, exhibiting variations of 0.5-1.0 mag in color between the center and the outer regions, opposite to the expectations of reddened metallicity induced gradients in passively evolved ellipticals. From a Magellan-Clay spectrum we secure the galaxy redshift at $z=0.624$. We find a strong X-ray source coincident with the spheroid galaxy. Spectral features and a high X-ray luminosity indicate the presence of an AGN in the galaxy. However, a comparison of the X-ray luminosity to a sample derived from the Chandra Deep Field South displays Lx to be comparable to Type I/QSO galaxies while the optical flux is consistent with a normal star-forming galaxy. We conclude that the galaxy's non-thermal component dominates at high-energy wavelengths while we associate the spheroid blue light with the stellar spectrum of normal star-forming galaxies. We argue about a probable association between the presence of blue cores in spheroids and AGN activity.

  2. Coupled Full-Core Problem witssh VERA

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

    Inc Rensselaer Polytechnic Institute Core Physics, Inc. Southern States Energy Board City University of New York Texas A&M University Florida State University University of...

  3. Sandia National Laboratories: QD core shell heterostructures

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

    QD core shell heterostructures Introduction of Prof. David Kelley and UC Merced to SSLS On January 11, 2012, in Energy Efficiency, News, News & Events, Partnership, Solid-State...

  4. The Outer Stellar Populations and Environments of Unusually HI-rich Galaxies

    E-Print Network [OSTI]

    Kauffmann, Guinevere

    2015-01-01T23:59:59.000Z

    We investigate the nature of HI-rich galaxies from the ALFALFA and GASS surveys, which are defined as galaxies in the top 10th percentile in atomic gas fraction at a given stellar mass. We analyze outer (R>1.5 Re) stellar populations for a subset of face-on systems using optical g-r versus r-z colour/colour diagrams. The results are compared with those from control samples that are defined without regard to atomic gas content, but are matched in redshift, stellar mass and structural parameters. HI-rich early-type (C>2.6) and late-type (C 10.5) HI-rich galaxies, regardless of type.

  5. Analyses of a steel containment vessel with an outer contact structure under severe internal overpressurization conditions

    SciTech Connect (OSTI)

    Porter, V.L.

    1993-12-31T23:59:59.000Z

    Many Mark-I and Mark-II BWR plants are designed with a steel vessel as the primary containment. Typically, the steel containment vessel (SCV) is enclosed within a reinforced concrete shield building with only a small gap (50--90mm) separating the two structures. This paper describes finite element analyses performed to evaluate the effects of contact and friction between a steel containment vessel and an outer contact structure when the containment vessel is subjected to large internal pressures. These computations were motivated by a joint program on containment integrity involving the Nuclear Power Engineering Corporation (NUPEC) of Japan, the US Nuclear Regulatory Commission (NRC), and Sandia National Laboratories for testing model containments.

  6. THE ACS NEARBY GALAXY SURVEY TREASURY. III. CEPHEIDS IN THE OUTER DISK OF M81

    SciTech Connect (OSTI)

    McCommas, Les P.; Williams, Benjamin F.; Dalcanton, Julianne J.; Davis, Matthew R. [Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195 (United States); Yoachim, Peter [Department of Astronomy and McDonald Observatory, University of Texas, Austin, TX 78712 (United States); Dolphin, Andrew E. [Raytheon Corporation, 870 Winter Street Waltham, MA 02451 (United States)], E-mail: lmccomma@astro.washington.edu, E-mail: jd@astro.washington.edu, E-mail: ben@astro.washington.edu, E-mail: mrdavis@astro.washington.edu, E-mail: yoachim@astro.as.utexas.edu, E-mail: adolphin@ratheon.com

    2009-06-15T23:59:59.000Z

    The ACS Nearby Galaxy Survey Treasury (ANGST) has acquired deep ACS imaging of a field in the outer disk of the large spiral galaxy M81. These data were obtained over a total of 20 Hubble Space Telescope orbits, providing a baseline long enough to reliably identify Cepheid variable stars in the field. Fundamental mode and first overtone types have been distinguished through comparative fits with corresponding Cepheid light curve templates derived from principal component analysis of confirmed Cepheids in the Large Magellanic Cloud (LMC), Small Magellanic Cloud, and Milky Way. A distance modulus of 27.78 {+-} 0.05 {sub r} {+-} 0.14 {sub s} with a corresponding distance of 3.60 {+-} 0.23 Mpc has been calculated from a sample of 11 fundamental mode and two first overtone Cepheids (assuming an LMC distance modulus of {mu}{sub LMC} = 18.41 {+-} 0.10 {sub r} {+-} 0.13 {sub s})

  7. OUTER-DISK POPULATIONS IN NGC 7793: EVIDENCE FOR STELLAR RADIAL MIGRATION

    SciTech Connect (OSTI)

    Radburn-Smith, David J.; Dalcanton, Julianne J. [Department of Astronomy, University of Washington, Seattle, WA 98195 (United States); Roskar, Rok [Institut fuer Theoretische Physik, Universitaet Zuerich (Switzerland); Debattista, Victor P. [Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE (United Kingdom); Streich, David; De Jong, Roelof S.; Vlajic, Marija [Leibniz-Institut fuer Astrophysik Potsdam, D-14482 Potsdam (Germany); Holwerda, Benne W. [European Space Agency, ESTEC, 2200 AG Noordwijk (Netherlands); Purcell, Chris W. [Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Dolphin, Andrew E. [Raytheon, 1151 E. Hermans Road, Tucson, AZ 85756 (United States); Zucker, Daniel B. [Department of Physics and Astronomy, Macquarie University, NSW 2109 (Australia)

    2012-07-10T23:59:59.000Z

    We analyzed the radial surface brightness profile of the spiral galaxy NGC 7793 using HST/ACS images from the GHOSTS survey and a new HST/WFC3 image across the disk break. We used the photometry of resolved stars to select distinct populations covering a wide range of stellar ages. We found breaks in the radial profiles of all stellar populations at 280'' ({approx}5.1 kpc). Beyond this disk break, the profiles become steeper for younger populations. This same trend is seen in numerical simulations where the outer disk is formed almost entirely by radial migration. We also found that the older stars of NGC 7793 extend significantly farther than the underlying H I disk. They are thus unlikely to have formed entirely at their current radii, unless the gas disk was substantially larger in the past. These observations thus provide evidence for substantial stellar radial migration in late-type disks.

  8. Protective effect of taurine on the light-induced disruption of isolated frog rod outer segments

    SciTech Connect (OSTI)

    Pasantes-Morales, H.; Ademe, R.M.; Quesada, O.

    1981-01-01T23:59:59.000Z

    Isolated frog rod outer segments (ROS) incubated in a Krebs-bicarbonate medium, and illuminated for 2 h, show a profound alteration in their structure. This is characterized by distention of discs, vesiculation, and a marked swelling. The light-induced ROS disruption requires the presence of bicarbonate and sodium chloride. Replacement of bicarbonate by TRIS or HEPES protects ROS structure. Also, substitution of sodium chloride by sucrose or choline chloride maintains unaltered the ROS structure. Deletion of calcium, magnesium, or phosphate does not modify the effect produced by illumination. An increased accumulation of labeled bicarbonate and tritiated water is observed in illuminated ROS, as compared with controls in the dark. The presence of taurine, GABA, or glycine, at concentrations of 5-25 mM, effectively counteracts the light-induced ROS disruption. Taurine (25 mM) reduces labeled bicarbonate and tritiated water levels to those observed in the dark incubated ROS.

  9. NON-EQUILIBRIUM CHEMISTRY OF DYNAMICALLY EVOLVING PRESTELLAR CORES. I. BASIC MAGNETIC AND NON-MAGNETIC MODELS AND PARAMETER STUDIES

    SciTech Connect (OSTI)

    Tassis, Konstantinos; Willacy, Karen; Yorke, Harold W.; Turner, Neal J. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

    2012-07-01T23:59:59.000Z

    We combine dynamical and non-equilibrium chemical modeling of evolving prestellar molecular cloud cores and investigate the evolution of molecular abundances in the contracting core. We model both magnetic cores, with varying degrees of initial magnetic support, and non-magnetic cores, with varying collapse delay times. We explore, through a parameter study, the competing effects of various model parameters in the evolving molecular abundances, including the elemental C/O ratio, the temperature, and the cosmic-ray ionization rate. We find that different models show their largest quantitative differences at the center of the core, whereas the outer layers, which evolve slower, have abundances which are severely degenerate among different dynamical models. There is a large range of possible abundance values for different models at a fixed evolutionary stage (central density), which demonstrates the large potential of chemical differentiation in prestellar cores. However, degeneracies among different models, compounded with uncertainties induced by other model parameters, make it difficult to discriminate among dynamical models. To address these difficulties, we identify abundance ratios between particular molecules, the measurement of which would have maximal potential for discrimination among the different models examined here. In particular, we find that the ratios between NH{sub 3} and CO, NH{sub 2} and CO, and NH{sub 3} and HCO{sup +} are sensitive to the evolutionary timescale, and that the ratio between HCN and OH is sensitive to the C/O ratio. Finally, we demonstrate that measurements of the central deviation (central depletion or enhancement) of abundances of certain molecules are good indicators of the dynamics of the core.

  10. Can direct extracellular electron transfer occur in the absence of outer membrane cytochromes in Desulfovibrio vulgaris?

    SciTech Connect (OSTI)

    Elias, Dwayne A [ORNL] [ORNL; Zane, Mr. Grant M. [University of Missouri, Columbia] [University of Missouri, Columbia; Auer, Dr. Manfred [Lawrence Berkeley National Laboratory (LBNL)] [Lawrence Berkeley National Laboratory (LBNL); Fields, Dr. Matthew Wayne [Montana State University] [Montana State University; Wall, Judy D. [University of Missouri] [University of Missouri; Gorby, Dr. Yuri A. [J. Craig Venter Institute] [J. Craig Venter Institute

    2010-01-01T23:59:59.000Z

    Extracellular electron transfer has been investigated over several decades via forms of soluble electron transfer proteins that are exported for extracellular reoxidation. More recently, several organisms have been shown to reduce extracellular metals via the direct transfer of electron through appendages; also known as nanowires. They have been reported most predominantly in Shewanella and Geobacter. While the relevancy and composition of these structures in each genus has been debated, both possess outer membrane cytochrome complexes that could theoretically come into direct contact with solid phase oxidized metals. Members of the genus Desulfovibrio apparently have no such cytochromes although similar appendages are present, are electrically conductive, and are different from flagella. Upon U(VI)-reduction, the structures in Desulfovibrio become coated with U(IV). Deletion of flagellar genes did not alter soluble or amorphous Fe(III) or U(VI) reduction, or appendage appearance. Removal of the chromosomal pilA gene hampered amorphous Fe(III)-reduction by ca. 25%, but cells lacking the native plasmid, pDV1, reduced soluble Fe(III) and U(VI) at ca. 50% of the wild type rate while amorphous Fe(III)-reduction slowed to ca. 20% of the wild type rate. Appendages were present in all deletions as well as pDV1, except pilA. Gene complementation restored all activities and morphologies to wild type levels. This suggests that pilA encodes the structural component, whereas genes within pDV1 may provide the reactive members. How such appendages function without outer membrane cytochromes is under investigation.

  11. TURBULENCE IN THE OUTER REGIONS OF PROTOPLANETARY DISKS. I. WEAK ACCRETION WITH NO VERTICAL MAGNETIC FLUX

    SciTech Connect (OSTI)

    Simon, Jacob B.; Armitage, Philip J.; Beckwith, Kris [JILA, University of Colorado and NIST, 440 UCB, Boulder, CO 80309-0440 (United States)] [JILA, University of Colorado and NIST, 440 UCB, Boulder, CO 80309-0440 (United States); Bai, Xue-Ning; Stone, James M., E-mail: jbsimon@jila.colorado.edu [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)

    2013-02-10T23:59:59.000Z

    We use local numerical simulations to investigate the strength and nature of magnetohydrodynamic (MHD) turbulence in the outer regions of protoplanetary disks, where ambipolar diffusion is the dominant non-ideal MHD effect. The simulations include vertical stratification and assume zero net vertical magnetic flux. We employ a super time-stepping technique to ameliorate the Courant restriction on the diffusive time step. We find that in idealized stratified simulations, with a spatially constant ambipolar Elsasser number Am, turbulence driven by the magnetorotational instability (MRI) behaves in a similar manner as in prior unstratified calculations. Turbulence dies away for Am {<=} 1, and becomes progressively more vigorous as ambipolar diffusion is decreased. Near-ideal MHD behavior is recovered for Am {>=} 10{sup 3}. In the intermediate regime (10 {<=} Am {<=} 10{sup 3}) ambipolar diffusion leads to substantial increases in both the period of the MRI dynamo cycle and the characteristic scales of magnetic field structures. To quantify the impact of ambipolar physics on disk accretion, we run simulations at 30 AU and 100 AU that include a vertical Am profile based upon far-ultraviolet (FUV) ionized disk models. These models develop a vertically layered structure analogous to the Ohmic dead zone that is present at smaller radii. We find that, although the levels of surface turbulence can be strong (and consistent with constraints on turbulent line widths at these radii), the inferred accretion rates are at least an order of magnitude smaller than those observed in T Tauri stars. This discrepancy is very likely due to the assumption of zero vertical magnetic field in our simulations and suggests that vertical magnetic fields are essential for MRI-driven accretion in the outer regions of protoplanetary disks.

  12. A MEGACAM SURVEY OF OUTER HALO SATELLITES. II. BLUE STRAGGLERS IN THE LOWEST STELLAR DENSITY SYSTEMS

    SciTech Connect (OSTI)

    Santana, Felipe A.; Munoz, Ricardo R. [Departamento de Astronomia, Universidad de Chile, Camino El Observatorio 1515, Las Condes, Santiago (Chile); Geha, Marla [Astronomy Department, Yale University, New Haven, CT 06520 (United States); Cote, Patrick; Stetson, Peter [Herzberg Institute of Astrophysics, National Research Council of Canada, Victoria, BC, V9E 2E7 (Canada); Simon, Joshua D. [Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Djorgovski, S. G., E-mail: fsantana@das.uchile.cl, E-mail: rmunoz@das.uchile.cl [Astronomy Department, California Institute of Technology, Pasadena, CA, 91125 (United States)

    2013-09-10T23:59:59.000Z

    We present a homogeneous study of blue straggler stars across 10 outer halo globular clusters, 3 classical dwarf spheroidal galaxies, and 9 ultra-faint galaxies based on deep and wide-field photometric data taken with MegaCam on the Canada-France-Hawaii Telescope. We find blue straggler stars to be ubiquitous among these Milky Way satellites. Based on these data, we can test the importance of primordial binaries or multiple systems on blue straggler star formation in low-density environments. For the outer halo globular clusters, we find an anti-correlation between the specific frequency of blue stragglers and absolute magnitude, similar to that previously observed for inner halo clusters. When plotted against density and encounter rate, the frequency of blue stragglers is well fit by a single trend with a smooth transition between dwarf galaxies and globular clusters; this result points to a common origin for these satellites' blue stragglers. The fraction of blue stragglers stays constant and high in the low encounter rate regime spanned by our dwarf galaxies, and decreases with density and encounter rate in the range spanned by our globular clusters. We find that young stars can mimic blue stragglers in dwarf galaxies only if their ages are 2.5 {+-} 0.5 Gyr and they represent {approx}1%-7% of the total number of stars, which we deem highly unlikely. These results point to mass-transfer or mergers of primordial binaries or multiple systems as the dominant blue straggler formation mechanism in low-density systems.

  13. A Particle Simulation for the Global Pulsar Magnetosphere: the Pulsar Wind linked to the Outer Gaps

    E-Print Network [OSTI]

    Tomohide Wada; Shinpei Shibata

    2007-01-05T23:59:59.000Z

    Soon after the discovery of radio pulsars in 1967, the pulsars are identified as strongly magnetic (typically $10^{12}$G) rapidly rotating ($\\sim 10^{2}-0.1$ Hz) neutron stars. However, the mechanism of particle acceleration in the pulsar magnetosphere has been a longstanding problem. The central problem is why the rotation power manifests itself in both gamma-ray beams and a highly relativistic wind of electron-positron plasmas, which excites surrounding nebulae observed in X-ray. Here we show with a three dimensional particle simulation for the global axisymmetric magnetosphere that a steady outflow of electron-positron pairs is formed with associated pair sources, which are the gamma-ray emitting regions within the light cylinder. The magnetic field is assumed to be dipole, and to be consistent, pair creation rate is taken to be small, so that the model might be applicable to old pulsars such as Geminga. The pair sources are charge-deficient regions around the null surface, and we identify them as the outer gap. The wind mechanism is the electromagnetic induction which brings about fast azimuthal motion and eventually trans-field drift by radiation drag in close vicinity of the light cylinder and beyond. The wind causes loss of particles from the system. This maintains charge deficiency in the outer gap and pair creation. The model is thus in a steady state, balancing loss and supply of particles. Our simulation implies how the wind coexists with the gamma-ray emitting regions in the pulsar magnetosphere.

  14. Simulating the outer layers of Procyon A: a comparison with the Sun

    E-Print Network [OSTI]

    F. J. Robinson; P. Demarque; D. B. Guenther; Y. -C. Kim; K. L. Chan

    2005-06-30T23:59:59.000Z

    Compared to the Sun, the atmospheric structure and convective flow in Procyon A exhibit the following characteristics: (1) the highly superadiabatic transition layer (SAL) is located at much shallower optical depth; it is in a dynamically active region, and its outer region is located part of the time in the optically thin atmosphere; (2) the outer region of the SAL moves from an optically thin region to thick region and back again over a time of 20-30 minutes. This motion, which is driven by the granulation, takes place in a time approximately half the turnover time of the largest granules; The main reason for the radically different radiative-convective behaviour in Procyon A compared to the Sun is the role played by turbulent eddies in determining the overall flow/thermal structure. The turbulent pressure and turbulent kinetic energy can exceed 50 % of the local gas pressure (compared to about 10-20 % in the Sun). The Procyon A simulation thus reveals two distinct timescales - the autocorrelation time of the vertical velocity and the characteristic timescale of the SAL which is tied to granulation. Just below the surface the autocorrelation decay time is about 5 minutes in Procyon A, and the SAL motion timescale is 20-30 mins. When the SAL penetrates the optically thin region there are efficient radiative losses and the peak of the SAL is low. We speculate that these losses damp out the relative amplitudes in luminosity (temperature fluctuations) compared to velocity (Doppler). Although this will not affect the frequencies of the peaks in the power spectrum, it will probably lower the average amplitude of the peaks relative to the noise background.

  15. Apparatus and methods for relieving thermally induced stresses in inner and outer bands of thermally cooled turbine nozzle stages

    DOE Patents [OSTI]

    Yu, Yufeng Phillip (Guilderland, NY); Itzel, Gary Michael (Clifton Park, NY); Correia, Victor H. S. (Milton Mills, NH)

    2002-01-01T23:59:59.000Z

    To control the temperature mismatch between the inner and outer bands and covers forming plenums with the inner and outer bands on sides thereof remote from the hot gas path, passages extend from the leading edge of the covers in communication with the hot gases of combustion to the trailing edge of the covers in communication with the hot gas flowpath. A mixing chamber is provided in each passage in communication with compressor discharge air for mixing the hot gases of combustion and compressor discharge air for flow through the passage, thereby heating the cover and minimizing the temperature differential between the inner and outer bands and their respective covers. The passages are particularly useful adjacent the welded or brazed joints between the covers and inner band portions.

  16. Core-Level Activity Prediction for Multi-Core Power Management

    E-Print Network [OSTI]

    John, Lizy Kurian

    1 Core-Level Activity Prediction for Multi-Core Power Management W. Lloyd Bircher1 and Lizy, University of Texas at Austin Abstract - Existing power management techniques operate by reducing performance generated by the workloads on individual cores. This causes sub-optimal power management and over

  17. Core Science Requirement Final Document Page 1 THE CORE SCIENCE REQUIREMENT and

    E-Print Network [OSTI]

    Lagalante, Anthony F.

    Core Science Requirement ­ Final Document ­ Page 1 THE CORE SCIENCE REQUIREMENT and MENDEL SCIENCE EXPERIENCE COURSES Core requirement of 2 semesters of science with laboratory; requirement to be met by the end of the sophomore year Rationale Science literacy is an integral part of the intellectual

  18. Pre-supernova neutrino emissions from ONe cores in the progenitors of core-collapse supernovae: are they distinguishable from those of Fe cores?

    E-Print Network [OSTI]

    Kato, Chinami; Yamada, Shoichi; Takahashi, Koh; Umeda, Hideyuki; Yoshida, Takashi; Ishidoshiro, Koji

    2015-01-01T23:59:59.000Z

    Aiming to distinguish two types of progenitors of core collapse supernovae, i.e., one with a core composed mainly of oxygen and neon (abbreviated as ONe core) and the other with an iron core (or Fe core), we calculated the luminosities and spectra of neutrinos emitted from these cores prior to gravitational collapse, taking neutrino oscillation into account. We found that the total energies emitted as $\\bar{\

  19. The Formation and Evolution of Prestellar Cores

    E-Print Network [OSTI]

    Philippe André; Shantanu Basu; Shu-ichiro Inutsuka

    2008-01-28T23:59:59.000Z

    Improving our understanding of the initial conditions and earliest stages of star formation is crucial to gain insight into the origin of stellar masses, multiple systems, and protoplanetary disks. We review the properties of low-mass dense cores as derived from recent millimeter/submillimeter observations of nearby molecular clouds and discuss them in the context of various contemporary scenarios for cloud core formation and evolution. None of the extreme scenarios can explain all observations. Pure laminar ambipolar diffusion has relatively long growth times for typical ionization levels and has difficulty satisfying core lifetime constraints. Purely hydrodynamic pictures have trouble accounting for the inefficiency of core formation and the detailed velocity structure of individual cores. A possible favorable scenario is a mixed model involving gravitational fragmentation of turbulent molecular clouds close to magnetic criticality. The evolution of the magnetic field and angular momentum in individual cloud cores after the onset of gravitational collapse is also discussed. In particular, we stress the importance of radiation-magnetohydrodynamical processes and resistive MHD effects during the protostellar phase. We also emphasize the role of the formation of the short-lived first (protostellar) core in providing a chance for sub-fragmentation into binary systems and triggering MHD outflows. Future submillimeter facilities such as Herschel and ALMA will soon provide major new observational constraints in this field. On the theoretical side, an important challenge for the future will be to link the formation of molecular clouds and prestellar cores in a coherent picture.

  20. UW-Milwaukee Strategic Planning Core Team

    E-Print Network [OSTI]

    Saldin, Dilano

    UW-Milwaukee Strategic Planning Core Team Minutes Tuesday, December 18, 2012 Regents Room, Chapman Hall, 8-10 a.m. 1. Welcome and meeting objectives 2. Core Team Suggested Guidelines ("Ground Rules") a. Communication (within team and with across campus and others) Input is always welcomed Open communication

  1. UNL Core for Applied Genomics and Ecology

    E-Print Network [OSTI]

    Farritor, Shane

    UNL Core for Applied Genomics and Ecology Bioinformatics training Roche 454 GS-FLX Registration, Microbiomes, Variant Analysis, Whole Genomes, Transcriptomes Data Analysis and Statistics CAGE database and employer. University of Nebraska-Lincoln*Core for Applied Genomics and Ecology* 323 Filley Hall *Lincoln

  2. Idealized Test Cases for Dynamical Core Experiments

    E-Print Network [OSTI]

    Jablonowski, Christiane

    Idealized Test Cases for Dynamical Core Experiments Christiane Jablonowski (University of Michigan-13/2006 #12;Motivation · Test cases for 3D dynamical cores on the sphere ­ are hard to find in the literature groups ­ lack standardized & easy-to-use analysis techniques · Idea: Establish a collection of test cases

  3. Moving core beam energy absorber and converter

    DOE Patents [OSTI]

    Degtiarenko, Pavel V.

    2012-12-18T23:59:59.000Z

    A method and apparatus for the prevention of overheating of laser or particle beam impact zones through the use of a moving-in-the-coolant-flow arrangement for the energy absorbing core of the device. Moving of the core spreads the energy deposition in it in 1, 2, or 3 dimensions, thus increasing the effective cooling area of the device.

  4. Experto Universitario Java Sesin 1: Spring core

    E-Print Network [OSTI]

    Escolano, Francisco

    Enterprise Spring © 2012-2013 Depto. Ciencia de la Computación e IA Spring core Puntos a tratar 2 #12;Experto Universitario Java Enterprise Spring © 2012-2013 Depto. Ciencia de la Computación e IA;Experto Universitario Java Enterprise Spring © 2012-2013 Depto. Ciencia de la Computación e IA Spring core

  5. Method and apparatus for recovering unstable cores

    DOE Patents [OSTI]

    McGuire, Patrick L. (Los Alamos, NM); Barraclough, Bruce L. (Los Alamos, NM)

    1983-01-01T23:59:59.000Z

    A method and apparatus suitable for stabilizing hydrocarbon cores are given. Such stabilized cores have not previously been obtainable for laboratory study, and such study is believed to be required before the hydrate reserves can become a utilizable resource. The apparatus can be built using commercially available parts and is very simple and safe to operate.

  6. Module Handbook Core Univ. of Oldenburg

    E-Print Network [OSTI]

    Habel, Annegret

    Energy Conversion Process · Location Dependence of Wind Energy Potential and Wind Energy Forecasting/EUREC Course 2008/2009 #12;EUREC Core Courses at University of Oldenburg, 1st Semester Wind Energy Module Module Description: Wind Energy Field: Core Oldenburg Courses: Wind Energy Wind Energy

  7. CFD Solvers on Many-core Processors

    E-Print Network [OSTI]

    Brandvik, Tobias

    2008-11-11T23:59:59.000Z

    cores with 4 · 106 transistors each gives 10 times the performance as 1 big core 0 0.5 1 1.5 2 2.5 3 3.5 4 x 108Number of transistors P e r f o r m a n c e CFD Solvers on Many-core Processors – p.8/36 Everyone is going parallel Every major chip vendor... on Many-core Processors – p.22/36 Stencil operations Evaluate ?2u?x2 on a regular grid: DO K=2,NK-1 DO J=2,NJ-1 DO I=2,NI-1 D2UDX2(I,J,K) = (U(I+1,J,K) - 2.0*U(I,J,K) + & U(I-1,J,K))/(DX*DX) END DO END DO END DO CFD Solvers on Many-core Processors – p.23...

  8. PRISMATIC CORE COUPLED TRANSIENT BENCHMARK

    SciTech Connect (OSTI)

    J. Ortensi; M.A. Pope; G. Strydom; R.S. Sen; M.D. DeHart; H.D. Gougar; C. Ellis; A. Baxter; V. Seker; T.J. Downar; K. Vierow; K. Ivanov

    2011-06-01T23:59:59.000Z

    The Prismatic Modular Reactor (PMR) is one of the High Temperature Reactor (HTR) design concepts that have existed for some time. Several prismatic units have operated in the world (DRAGON, Fort St. Vrain, Peach Bottom) and one unit is still in operation (HTTR). The deterministic neutronics and thermal-fluids transient analysis tools and methods currently available for the design and analysis of PMRs have lagged behind the state of the art compared to LWR reactor technologies. This has motivated the development of more accurate and efficient tools for the design and safety evaluations of the PMR. In addition to the work invested in new methods, it is essential to develop appropriate benchmarks to verify and validate the new methods in computer codes. The purpose of this benchmark is to establish a well-defined problem, based on a common given set of data, to compare methods and tools in core simulation and thermal hydraulics analysis with a specific focus on transient events. The benchmark-working group is currently seeking OECD/NEA sponsorship. This benchmark is being pursued and is heavily based on the success of the PBMR-400 exercise.

  9. Feasibility of Partial ZrO[subscript 2] Coatings on Outer Surface of Annular UO[subscript 2] Pellets to Control Gap Conductance

    E-Print Network [OSTI]

    Feinroth, H.

    The viability of depositing a thin porous coating of zirconia on the outer surface of an annular UO[subscript 2] pellet

  10. Solar wind structure in the outer heliosphere J.D. Richardson a,b,*, Y. Liu a

    E-Print Network [OSTI]

    California at Berkeley, University of

    Solar wind structure in the outer heliosphere J.D. Richardson a,b,*, Y. Liu a , C. Wang b a Kavli Academy of Sciences, P.O. Box 8701, Beijing 100080, China Received 29 November 2006; received in revised form 8 February 2007; accepted 27 March 2007 Abstract A solar wind parcel evolves as it moves outward

  11. Equatorial symmetry of Boussinesq convective solutions in a rotating spherical shell allowing rotation of the inner and outer spheres

    SciTech Connect (OSTI)

    Kimura, Keiji; Takehiro, Shin-ichi; Yamada, Michio [Research Institute for Mathematical Sciences, Kyoto University, Kyoto 606-8502 (Japan)

    2014-08-15T23:59:59.000Z

    We investigate properties of convective solutions of the Boussinesq thermal convection in a moderately rotating spherical shell allowing the respective rotation of the inner and outer spheres due to the viscous torque of the fluid. The ratio of the inner and outer radii of the spheres, the Prandtl number, and the Taylor number are fixed to 0.4, 1, and 500{sup 2}, respectively. The Rayleigh number is varied from 2.6 × 10{sup 4} to 3.4 × 10{sup 4}. In this parameter range, the behaviours of obtained asymptotic convective solutions are almost similar to those in the system whose inner and outer spheres are restricted to rotate with the same constant angular velocity, although the difference is found in the transition process to chaotic solutions. The convective solution changes from an equatorially symmetric quasi-periodic one to an equatorially symmetric chaotic one, and further to an equatorially asymmetric chaotic one, as the Rayleigh number is increased. This is in contrast to the transition in the system whose inner and outer spheres are assumed to rotate with the same constant angular velocity, where the convective solution changes from an equatorially symmetric quasi-periodic one, to an equatorially asymmetric quasi-periodic one, and to equatorially asymmetric chaotic one. The inner sphere rotates in the retrograde direction on average in the parameter range; however, it sometimes undergoes the prograde rotation when the convective solution becomes chaotic.

  12. Core analysis workstation development and verification

    SciTech Connect (OSTI)

    Mays, C.W.; Kochendarfer, R.A.; Mays, B.E.

    1987-01-01T23:59:59.000Z

    An engineering workstation utilizing a three-dimensional reactor simulator along with a series of auxiliary programs has been developed for use in predicting core reactivity and power distributions. This workstation can be used by both core analysis and core operations personnel. Expected applications are power distribution analyses, technical specification limit verification, and various types of reactivity analyses. Reactor operations personnel can quickly simulate load follow or other reactor maneuvers and, through the interactive graphics capability of the personal computer, the reactor responses, such as power distribution and control rod position, can be displayed and understood by operations personnel.

  13. A trans-outer membrane porin-cytochrome protein complex for extracellular electron transfer by Geobacter sulfurreducens PCA

    SciTech Connect (OSTI)

    Liu, Yimo; Wang, Zheming; Liu, Juan; Levar, Caleb; Edwards, Marcus; Babauta, Jerome T.; Kennedy, David W.; Shi, Zhi; Beyenal, Haluk; Bond, Daniel R.; Clarke, Thomas A.; Butt, Julea N.; Richardson, David J.; Rosso, Kevin M.; Zachara, John M.; Fredrickson, Jim K.; Shi, Liang

    2014-09-24T23:59:59.000Z

    The multiheme, outer membrane c-type cytochrome (c-Cyt) OmcB of Geobacter sulfurreducens was previously proposed to mediate electron transfer across the outer membrane. However, the underlying mechanism has remained uncharacterized. In G. sulfurreducens, the omcB gene is part of two tandem four-gene clusters, each is predicted to encode a transcriptional factor (OrfR/OrfS), a porin-like outer membrane protein (OmbB/OmbC), a periplasmic c-type cytochrome (OmaB/OmaC), and an outer membrane c-Cyt (OmcB/OmcC), respectively. Here we showed that OmbB/OmbC, OmaB/OmaC and OmcB/OmcC of G. sulfurreducens PCA formed the porin-cytochrome (Pcc) protein complexes, which were involved in transferring electrons across the outer membrane. The isolated Pcc protein complexes reconstituted in proteoliposomes transferred electrons from reduced methyl viologen across the lipid bilayer of liposomes to Fe(III)-citrate and ferrihydrite. The pcc clusters were found in all eight sequenced Geobacter and 11 other bacterial genomes from six different phyla, demonstrating a widespread distribution of Pcc protein complexes in phylogenetically diverse bacteria. Deletion of ombB-omaB-omcB-orfS-ombC-omaC-omcC gene clusters had no impact on the growth of G. sulfurreducens PCA with fumarate, but diminished the ability of G. sulfurreducens PCA to reduce Fe(III)-citrate and ferrihydrite. Complementation with the ombB-omaB-omcB gene cluster restored the ability of G. sulfurreducens PCA to reduce Fe(III)-citrate and ferrihydrite.

  14. Incorporation of silica into baroplastic core-shell nanoparticles

    E-Print Network [OSTI]

    Hewlett, Sheldon A

    2006-01-01T23:59:59.000Z

    Core-shell baroplastics are nanophase materials that exhibit pressure-induced flow at low temperatures and high pressures. Core-shell baroplastics used in this work are comprised of a low Tg poly(butyl acrylate) (PBA) core ...

  15. Initial Data for General Relativity Containing a Marginally Outer Trapped Torus

    E-Print Network [OSTI]

    Sascha Husa

    1996-06-15T23:59:59.000Z

    Asymptotically flat, time-symmetric, axially symmetric and conformally flat initial data for vacuum general relativity are studied numerically on $R^3$ with the interior of a standard torus cut out. By the choice of boundary condition the torus is marginally outer trapped, and thus a surface of minimal area. Apart from pure scaling the standard tori are parameterized by a radius $a\\in [0,1]$, where $a=0$ corresponds to the limit where the boundary torus degenerates to a circle and $a=1$ to a torus that touches the axis of symmetry. Noting that these tori are the orbits of a $U(1)\\times U(1)$ conformal isometry allows for a simple scheme to solve the constraint, involving numerical solution of only ordinary differential equations.The tori are unstable minimal surfaces (i.e. only saddle points of the area functional) and thus can not be apparent horizons, but are always surrounded by an apparent horizon of spherical topology, which is analyzed in the context of the hoop conjecture and isoperimetric inequality for black holes.

  16. The Outer Tracker Detector of the HERA-B Experiment Part I: Detector

    E-Print Network [OSTI]

    Albrecht, H

    2005-01-01T23:59:59.000Z

    The HERA-B Outer Tracker is a large system of planar drift chambers with about 113000 read-out channels. Its inner part has been designed to be exposed to a particle flux of up to 2.10^5 cm^-2 s^-1, thus coping with conditions similar to those expected for future hadron collider experiments. 13 superlayers, each consisting of two individual chambers, have been assembled and installed in the experiment. The stereo layers inside each chamber are composed of honeycomb drift tube modules with 5 and 10 mm diameter cells. Chamber aging is prevented by coating the cathode foils with thin layers of copper and gold, together with a proper drift gas choice. Longitudinal wire segmentation is used to limit the occupancy in the most irradiated detector regions to about 20 %. The production of 978 modules was distributed among six different laboratories and took 15 months. For all materials in the fiducial region of the detector good compromises of stability versus thickness were found. A closed-loop gas system supplies th...

  17. 3D convection simulations of the outer layers of the Sun using realistic physics

    E-Print Network [OSTI]

    F. J. Robinson; P. Demarque; L. H. Li; S. Sofia; Y. -C. Kim; K. L. Chan; D. B. Guenther

    2002-12-12T23:59:59.000Z

    This paper describes a series of 3D simulations of shallow inefficient convection in the outer layers of the Sun. The computational domain is a closed box containing the convection-radiation transition layer, located at the top of the solar convection zone. The most salient features of the simulations are that: i)The position of the lower boundary can have a major effect on the characteristics of solar surface convection (thermal structure, kinetic energy and turbulent pressure). ii)The width of the box has only a minor effect on the thermal structure, but a more significant effect on the dynamics (rms velocities). iii)Between the surface and a depth of 1 Mm, even though the density and pressure increase by an order of magnitude, the vertical correlation length of vertical velocity is always close to 600 km. iv) In this region the vertical velocity cannot be scaled by the pressure or the density scale height. This casts doubt on the applicability of the mixing length theory, not only in the superadiabatic layer, but also in the adjacent underlying layers. v) The final statistically steady state is not strictly dependent on the initial atmospheric stratification.

  18. Mapping the Outer Edge of the Young Stellar Cluster in the Galactic Center

    E-Print Network [OSTI]

    Støstad, Morten N; Murray, Norm; Lu, Jessica R; Yelda, Sylvana; Ghez, Andrea M

    2015-01-01T23:59:59.000Z

    We present new near-infrared spectroscopic observations of the outer edges of the young stellar cluster around the supermassive black hole at the Galactic center. The observations show a break in the surface-density profile of young stars at approximately 13 arcsec (0.52 pc). These observations spectroscopically confirm previous suggestions of a break based on photometry. Using Gemini North's Near-Infrared Integral Field Spectrometer (NIFS) we are able to detect and separate early- and late-type stars with a 75% completeness at Ks = 15.5. We sample a region with radii between 7" to 23" (0.28 pc to 0.92 pc) from Sgr A*, and present new spectral classifications of 144 stars brighter than Ks = 15.5, where 140 stars are late-type (> 1 Gyr) and only four stars are early-type (young, 4-6 Myr). A broken power-law fit of the early-type surface-density matches well with our data and previously published values. The projected surface-density of late-type stars is also measured and found to be consistent with previous r...

  19. KSI's Cross Insulated Core Transformer Technology

    SciTech Connect (OSTI)

    Uhmeyer, Uwe [Kaiser Systems, Inc, 126 Sohier Road, Beverly, MA 01915 (United States)

    2009-08-04T23:59:59.000Z

    Cross Insulated Core Transformer (CCT) technology improves on Insulated Core Transformer (ICT) implementations. ICT systems are widely used in very high voltage, high power, power supply systems. In an ICT transformer ferrite core sections are insulated from their neighboring ferrite cores. Flux leakage is present at each of these insulated gaps. The flux loss is raised to the power of stages in the ICT design causing output voltage efficiency to taper off with increasing stages. KSI's CCT technology utilizes a patented technique to compensate the flux loss at each stage of an ICT system. Design equations to calculate the flux compensation capacitor value are presented. CCT provides corona free operation of the HV stack. KSI's CCT based High Voltage power supply systems offer high efficiency operation, high frequency switching, low stored energy and smaller size over comparable ICT systems.

  20. Magnetic core studies at LBNL and LLNL

    E-Print Network [OSTI]

    Molvik, A.W.

    2008-01-01T23:59:59.000Z

    LLNL) and DE-AC03-76SF00098 (LBNL). References Wayne Meier,Magnetic Core Studies at LBNL and LLNL A. W. Molvik a,* , A.Livermore, CA 94550, USA LBNL, Berkeley, CA 94720, USA c

  1. Panelized wall system with foam core insulation

    DOE Patents [OSTI]

    Kosny, Jan (Oak Ridge, TN); Gaskin, Sally (Houston, TX)

    2009-10-20T23:59:59.000Z

    A wall system includes a plurality of wall members, the wall members having a first metal panel, a second metal panel, and an insulating core between the first panel and the second panel. At least one of the first panel and the second panel include ridge portions. The insulating core can be a foam, such as a polyurethane foam. The foam can include at least one opacifier to improve the k-factor of the foam.

  2. Viscosity anomaly in core-softened liquids

    E-Print Network [OSTI]

    Yu. D. Fomin; V. N. Ryzhov

    2013-03-18T23:59:59.000Z

    The present article presents a molecular dynamics study of several anomalies of core-softened systems. It is well known that many core-softened liquids demonstrate diffusion anomaly. Usual intuition relates the diffusion coefficient to shear viscosity via Stockes-Einstein relation. However, it can break down at low temperature. In this respect it is important to see if viscosity also demonstrates anomalous behavior.

  3. Formed Core Sampler Hydraulic Conductivity Testing

    SciTech Connect (OSTI)

    Miller, D. H.; Reigel, M. M.

    2012-09-25T23:59:59.000Z

    A full-scale formed core sampler was designed and functionally tested for use in the Saltstone Disposal Facility (SDF). Savannah River National Laboratory (SRNL) was requested to compare properties of the formed core samples and core drilled samples taken from adjacent areas in the full-scale sampler. While several physical properties were evaluated, the primary property of interest was hydraulic conductivity. Differences in hydraulic conductivity between the samples from the formed core sampler and those representing the bulk material were noted with respect to the initial handling and storage of the samples. Due to testing conditions, the site port samples were exposed to uncontrolled temperature and humidity conditions prior to testing whereas the formed core samples were kept in sealed containers with minimal exposure to an uncontrolled environment prior to testing. Based on the results of the testing, no significant differences in porosity or density were found between the formed core samples and those representing the bulk material in the test stand.

  4. Solid oxide fuel cell having monolithic core

    DOE Patents [OSTI]

    Ackerman, J.P.; Young, J.E.

    1983-10-12T23:59:59.000Z

    A solid oxide fuel cell is described for electrochemically combining fuel and oxidant for generating galvanic output, wherein the cell core has an array of electrolyte and interconnect walls that are substantially devoid of any composite inert materials for support. Instead, the core is monolithic, where each electrolyte wall consists of thin layers of cathode and anode materials sandwiching a thin layer of electrolyte material therebetween. The electrolyte walls are arranged and backfolded between adjacent interconnect walls operable to define a plurality of core passageways alternately arranged where the inside faces thereof have only the anode material or only the cathode material exposed. Means direct the fuel to the anode-exposed core passageways and means direct the oxidant to the anode-exposed core passageways and means direct the oxidant to the cathode-exposed core passageway; and means also direct the galvanic output to an exterior circuit. Each layer of the electrolyte and interconnect materials is of the order of 0.002 to 0.01 cm thick; and each layer of the cathode and anode materials is of the order of 0.002 to 0.05 cm thick.

  5. Core-Shell Structured Magnetic Ternary Nanocubes

    SciTech Connect (OSTI)

    Wang, Lingyan; Wang, Xin; Luo, Jin; Wanjala, Bridgid N.; Wang, Chong M.; Chernova, Natalya; Engelhard, Mark H.; Liu, Yao; Bae, In-Tae; Zhong, Chuan-Jian

    2010-12-01T23:59:59.000Z

    While transition metal-doped ferrite nanoparticles constitute an important class of soft magnetic nanomaterials with spinel structures, the ability to control the shape and composition would enable a wide range of applications in homogeneous or heterogeneous reactions such as catalysis and magnetic separation of biomolecules. This report describes novel findings of an investigation of core-shell structured MnZn ferrite nanocubes synthesized in organic solvents by manipulating the reaction temperature and capping agent composition in the absence of the conventionally-used reducing agents. The core-shell structure of the highly-monodispersed nanocubes (~20 nm) are shown to consist of an Fe3O4 core and an (Mn0.5Zn0.5)(Fe0.9, Mn1.1)O4 shell. In comparison with Fe3O4 and other binary ferrite nanoparticles, the core-shell structured nanocubes were shown to display magnetic properties regulated by a combination of the core-shell composition, leading to a higher coercivity (~350 Oe) and field-cool/zero-field-cool characteristics drastically different from many regular MnZn ferrite nanoparticles. The findings are discussed in terms of the unique core-shell composition, the understanding of which has important implication to the exploration of this class of soft magnetic nanomaterials in many potential applications such as magnetic resonance imaging, fuel cells, and batteries.

  6. The compactness of presupernova stellar cores

    SciTech Connect (OSTI)

    Sukhbold, Tuguldur; Woosley, S. E., E-mail: sukhbold@ucolick.org [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)

    2014-03-01T23:59:59.000Z

    The success or failure of the neutrino-transport mechanism for producing a supernova in an evolved massive star is known to be sensitive not only to the mass of the iron core that collapses, but also to the density gradient in the silicon and oxygen shells surrounding that core. Here we study the systematics of a presupernova core's 'compactness' as a function of the mass of the star and the physics used in its calculation. Fine-meshed surveys of presupernova evolution are calculated for stars from 15 to 65 M {sub ?}. The metallicity and the efficiency of semiconvection and overshoot mixing are both varied and bare carbon-oxygen cores are explored as well as full hydrogenic stars. Two different codes, KEPLER and MESA, are used for the study. A complex interplay of carbon and oxygen burning, especially in shells, can cause rapid variations in the compactness for stars of very nearly the same mass. On larger scales, the distribution of compactness with main sequence mass is found to be robustly non-monotonic, implying islands of 'explodabilty,' particularly around 8-20 M {sub ?} and 25-30 M {sub ?}. The carbon-oxygen (CO) core mass of a presupernova star is a better, (though still ambiguous) discriminant of its core structure than the main sequence mass.

  7. CSAT Role-Based/Core Competency Training Program | Department...

    Energy Savers [EERE]

    Services Training Cybersecurity Training Warehouse DOE Training & Education CSAT Role-BasedCore Competency Training Program CSAT Role-BasedCore Competency Training...

  8. Probing the Dynamics of a Protein Hydrophobic Core by Deutron...

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

    Dynamics of a Protein Hydrophobic Core by Deutron Solid-State Nuclear Magnetic Resonance Spectroscopy . Probing the Dynamics of a Protein Hydrophobic Core by Deutron Solid-State...

  9. Synthesis of Lutetium Phosphate/Apoferritin Core-Shell Nanoparticles...

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

    Lutetium PhosphateApoferritin Core-Shell Nanoparticles for Potential Applications in Radioimmunoimaging and Synthesis of Lutetium PhosphateApoferritin Core-Shell Nanoparticles...

  10. Nanoscale Alloying, Phase-Segregation, and Core-Shell Evolution...

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

    Alloying, Phase-Segregation, and Core-Shell Evolution of Gold-Platinum Nanoparticles and Their Electrocatalytic Effect Nanoscale Alloying, Phase-Segregation, and Core-Shell...

  11. Biocompatible core-shell magnetic nanoparticles for cancer treatment...

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

    Biocompatible core-shell magnetic nanoparticles for cancer treatment. Biocompatible core-shell magnetic nanoparticles for cancer treatment. Abstract: Non-toxic magnetic...

  12. Thermonuclear explosion of rotating massive stars could explain core-collapse supernovae

    E-Print Network [OSTI]

    Kushnir, Doron

    2015-01-01T23:59:59.000Z

    It is widely thought that core-collapse supernovae (CCSNe), the explosions of massive stars following the collapse of the stars' iron cores, is obtained due to energy deposition by neutrinos. So far, this scenario was not demonstrated from first principles. Kushnir and Katz (2014) have recently shown, by using one-dimensional simulations, that if the neutrinos failed to explode the star, a thermonuclear explosion of the outer shells is possible for some (tuned) initial profiles. However, the energy released was small and negligible amounts of ejected $^{56}$Ni were obtained, implying that these one-dimensional collapse induced thermonuclear explosions (CITE) are unlikely to represent typical CCSNe. Here I provide evidence supporting a scenario in which the majority of CCSNe are the result of CITE. I use two-dimensional simulations to show that collapse of stars that include slowly (few percent of breakup) rotating $\\sim0.1-10\\,M_{\\odot}$ shells of mixed helium-oxygen, leads to an ignition of a thermonuclear d...

  13. Turbulence driven diffusion in protoplanetary disks - chemical effects in the outer disk

    E-Print Network [OSTI]

    K. Willacy; W. D. Langer; M. Allen; G. Bryden

    2006-03-03T23:59:59.000Z

    The dynamics and chemistry of protostellar disks are likely to be intricately linked, with dynamical processes altering the chemical composition, and chemistry, in turn, controlling the ionization structure and hence the ability of the magneto-rotational instability to drive the disk turbulence. Here we present the results from the first chemical models of the outer regions (R > 100 AU) of protoplanetary disks to consider the effects of turbulence driven diffusive mixing in the vertical direction. We show that vertical diffusion can greatly affect the column densities of many species, increasing them by factors of up to two orders of magnitude. Previous disk models have shown that disks can be divided into three chemically distinct layers, with the bulk of the observed molecular emission coming from a region between an atomic/ionic layer on the surface of the disk and the midplane regoin where the bulk of molecules are frozen onto grains. Diffusion retains this three layer structure, but increases the depth of the molecular layer by bringing atoms and atomic ions form by photodissociation in the surface layers into the shielded molecular layer where molecules can reform. For other species, notably NH3 and N2H+, the column densities are relatively unaffected by diffusion. These species peak in abundance near the midplane where most other molecules are heavily depleted, rather than in the molecular layer above. Diffusion only affects the abundances of those molecules with peak abundances in the molecular layer. We find that diffusion does not affect the ionization fraction of the disk. We compare the calculated column densities to observations of DM Tau, LkCa 15 and TW Hya and find good agreement for many molecules with a diffusion coefficient of 1e18 cm^2 s^-1.

  14. Overview on Hydrate Coring, Handling and Analysis

    SciTech Connect (OSTI)

    Jon Burger; Deepak Gupta; Patrick Jacobs; John Shillinglaw

    2003-06-30T23:59:59.000Z

    Gas hydrates are crystalline, ice-like compounds of gas and water molecules that are formed under certain thermodynamic conditions. Hydrate deposits occur naturally within ocean sediments just below the sea floor at temperatures and pressures existing below about 500 meters water depth. Gas hydrate is also stable in conjunction with the permafrost in the Arctic. Most marine gas hydrate is formed of microbially generated gas. It binds huge amounts of methane into the sediments. Worldwide, gas hydrate is estimated to hold about 1016 kg of organic carbon in the form of methane (Kvenvolden et al., 1993). Gas hydrate is one of the fossil fuel resources that is yet untapped, but may play a major role in meeting the energy challenge of this century. In June 2002, Westport Technology Center was requested by the Department of Energy (DOE) to prepare a ''Best Practices Manual on Gas Hydrate Coring, Handling and Analysis'' under Award No. DE-FC26-02NT41327. The scope of the task was specifically targeted for coring sediments with hydrates in Alaska, the Gulf of Mexico (GOM) and from the present Ocean Drilling Program (ODP) drillship. The specific subjects under this scope were defined in 3 stages as follows: Stage 1: Collect information on coring sediments with hydrates, core handling, core preservation, sample transportation, analysis of the core, and long term preservation. Stage 2: Provide copies of the first draft to a list of experts and stakeholders designated by DOE. Stage 3: Produce a second draft of the manual with benefit of input from external review for delivery. The manual provides an overview of existing information available in the published literature and reports on coring, analysis, preservation and transport of gas hydrates for laboratory analysis as of June 2003. The manual was delivered as draft version 3 to the DOE Project Manager for distribution in July 2003. This Final Report is provided for records purposes.

  15. Development of Toroidal Core Transformers

    SciTech Connect (OSTI)

    Leon, Francisco

    2014-05-31T23:59:59.000Z

    The original objective of this project was to design, build and test a few prototypes of singlephase dry-type distribution transformers of 25 kVA, 2.4 kV primary to 120 V transformers using cores made of a continuous steel strip shaped like a doughnut (toroid). At different points during the development of the project, the scope was enhanced to include the more practical case of a 25 kVA transformer for a 13.8 kV primary system voltage. Later, the scope was further expanded to design and build a 50 kVA unit to transformer voltage from 7.62 kV to 2x120 V. This is a common transformer used by Con Edison of New York and they are willing to test it in the field. The project officially started in September 2009 and ended in May 2014. The progress was reported periodically to DOE in eighteen quarterly reports. A Continuation Application was submitted to DOE in June 2010. In May 2011 we have requested a non-cost extension of the project. In December 2011, the Statement of Project Objectives (SOPO) was updated to reflect the real conditions and situation of the project as of 2011. A second Continuation Application was made and funding was approved in 2013 by DOE and the end date was extended to May 2014. The technical challenges that were overcome in this project include: the development of the technology to pass the impulse tests, derive a model for the thermal performance, produce a sound mechanical design, and estimate the inrush current. However, the greatest challenge that we faced during the development of the project was the complications of procuring the necessary parts and materials to build the transformers. The actual manufacturing process is relatively fast, but getting all parts together is a very lengthy process. The main products of this project are two prototypes of toroidal distribution transformers of 7.62 kV (to be used in a 13.8 kV system) to 2x120 V secondary (standard utilization voltage); one is rated at 25 kVA and the other at 50 kVA. The 25 kVA transformer passed the impulse test in KEMA high-voltage laboratories. Additional products include: nine papers published in the IEEE Transactions on Power Delivery, one patent has been filed, three PhD students weresupported from beginning to graduation, five postdoctoral fellows, and three MSc students were partially supported. The electrical characteristics of our dry-type toroidal transformers are similar to those of the oil-immersed pole mounted transformers currently in use by many utilities, but toroids have higher efficiency. The no-load losses of the 50 kVA prototype are only 45 W. A standard transformer has no-load losses between 90 and 240 W. Thus, even the finest transformer built today with standard technology has double the amount of no-load losses than the prototype toroidal transformer. When the manufacturing process is prepared for mass production, the cost of a dry-type toroidal transformer would be similar to the price of an oil-filed standard design. However, because of the greatly reduced losses, the total ownership cost of a toroidal transformer could be about half of a traditional design. We got a grant from Power Bridge NY in the amount of $149,985 from June 2014 to May 2015 to continue developing the transformer with commercialization objectives. We are considering the possibility to incorporate a company to manufacture the transformers and have contacted investors. The current status of the real life testing is as follows: after several months of silence, Con Edison has re-started conversations and has shown willingness to test the transformer. Other companies, PSE&G and National Grid have recently also shown interest and we will present our product to them soon.

  16. A transmission/escape probabilities model for neutral particle transport in the outer regions of a diverted tokamak

    SciTech Connect (OSTI)

    Stacey, W.M.

    1992-12-01T23:59:59.000Z

    A new computational model for neutral particle transport in the outer regions of a diverted tokamak plasma chamber is presented. The model is based on the calculation of transmission and escape probabilities using first-flight integral transport theory and the balancing of fluxes across the surfaces bounding the various regions. The geometrical complexity of the problem is included in precomputed probabilities which depend only on the mean free path of the region.

  17. A proposal for federal legislation for the protection and preservation of submerged cultural resources on the outer continental shelf

    E-Print Network [OSTI]

    Hamilton, Richard Evans

    1978-01-01T23:59:59.000Z

    on the Outer Continental Shelf. (August 1978) Richard Evans Hamilton, B. S. , University of Michigan Chairman of Advisory Committee: John L. Seymour This thesis examines English and American court cases to determine the origin and applications of the so.... With these techniques, in 1968 and 1969, archaeo- logists raised and reconstructed an entire fourth-century B. C. merchant vessel sunk off the coast of Kyrenia, Cyprus. Borrowing 5 the technology of the offshore oil industry, in the form of magneto- meters, metal...

  18. Hurricane Andrew's impact on natural gas and oil facilities on the outer continental shelf (interim report as of November 1993)

    SciTech Connect (OSTI)

    Daniels, G.R.

    1994-01-01T23:59:59.000Z

    The interim report reviews Hurricane Andrew's impact on Federal Outer Continental Shelf (OCS) natural gas and oil drilling and production facilities. The report provides background on Hurricane Andrew's progression, discusses how OCS operators responded to the storm, summarizes the types of damage to offshore facilies caused by Hurricane Andrew, and discusses Minerals Management Service's continuing damage assessment and repair efforts. The summaries of damage estimates are presented in tables in Appendix 1. A glossary of report terminology is provided in Appendix 2.

  19. Solid oxide fuel cell having monolithic core

    DOE Patents [OSTI]

    Ackerman, John P. (Downers Grove, IL); Young, John E. (Woodridge, IL)

    1984-01-01T23:59:59.000Z

    A solid oxide fuel cell for electrochemically combining fuel and oxidant for generating galvanic output, wherein the cell core has an array of electrolyte and interconnect walls that are substantially devoid of any composite inert materials for support. Instead, the core is monolithic, where each electrolyte wall consists of thin layers of cathode and anode materials sandwiching a thin layer of electrolyte material therebetween, and each interconnect wall consists of thin layers of the cathode and anode materials sandwiching a thin layer of interconnect material therebetween. The electrolyte walls are arranged and backfolded between adjacent interconnect walls operable to define a plurality of core passageways alternately arranged where the inside faces thereof have only the anode material or only the cathode material exposed. Means direct the fuel to the anode-exposed core passageways and means direct the oxidant to the cathode-exposed core passageway; and means also direct the galvanic output to an exterior circuit. Each layer of the electrolyte and interconnect materials is of the order of 0.002-0.01 cm thick; and each layer of the cathode and anode materials is of the order of 0.002-0.05 cm thick.

  20. HIGH-ALBEDO C-COMPLEX ASTEROIDS IN THE OUTER MAIN BELT: THE NEAR-INFRARED SPECTRA

    SciTech Connect (OSTI)

    Kasuga, Toshihiro [Public Relations Center, National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Usui, Fumihiko; Hasegawa, Sunao [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo-ku, Sagamihara 252-5210 (Japan); Ootsubo, Takafumi [Astronomical Institute, Tohoku University, 6-3 Aoba, Aramaki, Aoba-ku, Sendai 980-8578 (Japan); Kuroda, Daisuke, E-mail: toshi.kasuga@nao.ac.jp [Okayama Astrophysical Observatory, National Astronomical Observatory of Japan, 3037-5 Honjo, Kamogata, Asakuchi, Okayama 719-0232 (Japan)

    2013-07-01T23:59:59.000Z

    Primitive, outer-belt asteroids are generally of low albedo, reflecting carbonaceous compositions like those of CI and CM meteorites. However, a few outer-belt asteroids having high albedos are known, suggesting the presence of unusually reflective surface minerals or, conceivably, even exposed water ice. Here, we present near-infrared (1.1-2.5 {mu}m) spectra of four outer-belt C-complex asteroids with albedos {>=}0.1. We find no absorption features characteristic of water ice (near 1.5 and 2.0 {mu}m) in the objects. Intimate mixture models set limits to the water ice by weight {<=}2%. Asteroids (723) Hammonia and (936) Kunigunde are featureless and have (60%-95%) amorphous Mg pyroxenes that might explain the high albedos. Asteroid (1276) Ucclia also shows a featureless reflection spectrum with (50%-60%) amorphous Mg pyroxenes. Asteroid (1576) Fabiola shows a possible weak, broad absorption band (1.5-2.1 {mu}m). The feature can be reproduced by (80%) amorphous Mg pyroxenes or orthopyroxene (crystalline silicate), either of which is likely to cause its high albedo. We discuss the origin of high-albedo components in primitive asteroids.

  1. Core-annular flow through a horizontal pipe: Hydrodynamic counterbalancing of buoyancy force on core

    E-Print Network [OSTI]

    Vuik, Kees

    Core-annular flow through a horizontal pipe: Hydrodynamic counterbalancing of buoyancy force of a high-viscosity liquid core surrounded by a low-viscosity liquid annular layer through a horizontal pipe through a horizontal pipe. Since the densities of the two liq- uids are almost always different, gravity

  2. Neutrino flavor transformation in core-collapse supernovae

    E-Print Network [OSTI]

    Cherry, John F.; Cherry, John F.

    2012-01-01T23:59:59.000Z

    in Supernovae . . . . . . . . . . . . . . . . . . . . .Collapse Supernovae . . . . . . . . . . . . . . . . . . . .Mechanisms of Core-Collapse Supernovae: Simulation Results

  3. 2.0 CORE LOGO 2.01 OVERVIEW

    E-Print Network [OSTI]

    Dellaire, Graham

    2.0 CORE LOGO 2.01 OVERVIEW 2.02 CLEAR SPACE AND MINIMUM SIZE 2.03 EXAMPLES OF PLACEMENT APPLIED TO THE CORE LOGO 2.08 APPLYING THE LOGO PROPERLY 2.09 LINKS TO DALHOUSIE AUTHORIZED CORE LOGO as a university with real substance and stature, and seen as a vibrant, welcoming community. Our core logo

  4. MODELING THE FORMATION OF GIANT PLANET CORES. I. EVALUATING KEY PROCESSES

    SciTech Connect (OSTI)

    Levison, Harold F. [Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80302 (United States); Thommes, Edward [Department of Physics, University of Guelph, Guelph, Ontario N1G 2W1 (Canada); Duncan, Martin J. [Department of Physics, Queen's University, Kingston, Ontario K7L 3N6 (Canada)], E-mail: hal@boulder.swri.edu

    2010-04-15T23:59:59.000Z

    One of the most challenging problems we face in our understanding of planet formation is how Jupiter and Saturn could have formed before the solar nebula dispersed. The most popular model of giant planet formation is the so-called core accretion model. In this model a large planetary embryo formed first, mainly by two-body accretion. This is then followed by a period of inflow of nebular gas directly onto the growing planet. The core accretion model has an Achilles heel, namely the very first step. We have undertaken the most comprehensive study of this process to date. In this study, we numerically integrate the orbits of a number of planetary embryos embedded in a swarm of planetesimals. In these experiments, we have included a large number of physical processes that might enhance accretion. In particular, we have included (1) aerodynamic gas drag, (2) collisional damping between planetesimals, (3) enhanced embryo cross sections due to their atmospheres, (4) planetesimal fragmentation, and (5) planetesimal-driven migration. We find that the gravitational interaction between the embryos and the planetesimals leads to the wholesale redistribution of material-regions are cleared of material and gaps open near the embryos. Indeed, in 90% of our simulations without fragmentation, the region near those embryos is cleared of planetesimals before much growth can occur. Thus, the widely used assumption that the surface density distribution of planetesimals is smooth can lead to misleading results. In the remaining 10% of our simulations, the embryos undergo a burst of outward migration that significantly increases growth. On timescales of {approx}10{sup 5} years, the outer embryo can migrate {approx}6 AU and grow to roughly 30 M {sub +}. This represents a largely unexplored mode of core formation. We also find that the inclusion of planetesimal fragmentation tends to inhibit growth except for a narrow range of fragment migration rates.

  5. Start-up fuel and power flattening of sodium-cooled candle core

    SciTech Connect (OSTI)

    Takaki, Naoyuki; Sagawa, Yu; Umino, Akitake [Department of Nuclear Safety Engineering, Tokyo City University 1-28-1 Tamazutsumi, Setagaya, Tokyo 158-8557 (Japan); Sekimoto, Hiroshi [University of California, Berkeley, CA 94720 (United States)

    2013-07-01T23:59:59.000Z

    The hard neutron spectrum and unique power shape of CANDLE enable its distinctive performances such as achieving high burnup more than 30% and exempting necessity of both enrichment and reprocessing. On the other hand, they also cause several challenging problems. One is how the initial fuel can be prepared to start up the first CANDLE reactor because the equilibrium fuel composition that enables stable CANDLE burning is complex both in axial and radial directions. Another prominent problem is high radial power peaking factor that worsens averaged burnup, namely resource utilization factor in once-through mode and shorten the life time of structure materials. The purposes of this study are to solve these two problems. Several ideas for core configurations and startup fuel using single enrichment uranium and iron as a substitute of fission products are studied. As a result, it is found that low enriched uranium is applicable to ignite the core but all concepts examined here exceeded heat limits. Adjustment in enrichment and height of active and burnt zone is opened for future work. Sodium duct assemblies and thorium fuel assemblies loaded in the center region are studied as measures to reduce radial power peaking factor. Replacing 37 fuels by thorium fuel assemblies in the zeroth to third row provides well-balanced performance with flattened radial power distribution. The CANDLE core loaded with natural uranium in the outer and thorium in the center region achieved 35.6% of averaged burnup and 7.0 years of cladding life time owing to mitigated local fast neutron irradiation at the center. Using thorium with natural or depleted uranium in CANDLE reactor is also beneficial to diversifying fission resource and extending available term of fission energy without expansion of needs for enrichment and reprocessing.

  6. Asteroseismic Diagnostics of Stellar Convective Cores

    E-Print Network [OSTI]

    Anwesh Mazumdar; Sarbani Basu; Braxton L. Collier; Pierre Demarque

    2006-08-16T23:59:59.000Z

    We present a detailed study of the small frequency separations as diagnostics of the mass of the convective core and evolutionary stage of solar-type stars. We demonstrate how the small separations can be combined to provide sensitive tests for the presence of convective overshoot at the edge of the core. These studies are focused on low degree oscillation modes, the only modes expected to be detected in distant stars. Using simulated data with realistic errors, we find that the mass of the convective core can be estimated to within 5% if the total stellar mass is known. Systematic errors arising due to uncertainty in the mass could be up to 20%. The evolutionary stage of the star, determined in terms of the central hydrogen abundance using our proposed technique, however, is much less sensitive to the mass estimate.

  7. Analytical Chemistry Core Capability Assessment - Preliminary Report

    SciTech Connect (OSTI)

    Barr, Mary E. [Los Alamos National Laboratory; Farish, Thomas J. [Los Alamos National Laboratory

    2012-05-16T23:59:59.000Z

    The concept of 'core capability' can be nebulous one. Even at a fairly specific level, where core capability equals maintaining essential services, it is highly dependent upon the perspective of the requestor. Samples are submitted to analytical services because the requesters do not have the capability to conduct adequate analyses themselves. Some requests are for general chemical information in support of R and D, process control, or process improvement. Many analyses, however, are part of a product certification package and must comply with higher-level customer quality assurance requirements. So which services are essential to that customer - just those for product certification? Does the customer also (indirectly) need services that support process control and improvement? And what is the timeframe? Capability is often expressed in terms of the currently utilized procedures, and most programmatic customers can only plan a few years out, at best. But should core capability consider the long term where new technologies, aging facilities, and personnel replacements must be considered? These questions, and a multitude of others, explain why attempts to gain long-term consensus on the definition of core capability have consistently failed. This preliminary report will not try to define core capability for any specific program or set of programs. Instead, it will try to address the underlying concerns that drive the desire to determine core capability. Essentially, programmatic customers want to be able to call upon analytical chemistry services to provide all the assays they need, and they don't want to pay for analytical chemistry services they don't currently use (or use infrequently). This report will focus on explaining how the current analytical capabilities and methods evolved to serve a variety of needs with a focus on why some analytes have multiple analytical techniques, and what determines the infrastructure for these analyses. This information will be useful in defining a roadmap for what future capability needs to look like.

  8. Development of Yangbajing Air shower Core detector array for a new EAS hybrid Experiment

    E-Print Network [OSTI]

    Jinsheng Liu; Jing Huang; Ding Chen; Ying Zhang; Liuming Zhai; Xu Chen; Xiaobin Hu; Yuhui Lin; Xueyao Zhang; Cunfeng Feng; Huanyu Jia; Xunxiu Zhou; DanZengLuoBu; Tianlu Chen; Haijin Li; Maoyuan Liu; Aifang Yuan

    2015-01-26T23:59:59.000Z

    Aiming at the observation of cosmic-ray chemical composition at the "knee" energy region, we have been developinga new type air-shower core detector (YAC, Yangbajing Air shower Core detector array) to be set up at Yangbajing (90.522$^\\circ$ E, 30.102$^\\circ$ N, 4300 m above sea level, atmospheric depth: 606 g/m$^2$) in Tibet, China. YAC works together with the Tibet air-shower array (Tibet-III) and an underground water cherenkov muon detector array (MD) as a hybrid experiment. Each YAC detector unit consists of lead plates of 3.5 cm thick and a scintillation counter which detects the burst size induced by high energy particles in the air-shower cores. The burst size can be measured from 1 MIP (Minimum Ionization Particle) to $10^{6}$ MIPs. The first phase of this experiment, named "YAC-I", consists of 16 YAC detectors each having the size 40 cm $\\times$ 50 cm and distributing in a grid with an effective area of 10 m$^{2}$. YAC-I is used to check hadronic interaction models. The second phase of the experiment, called "YAC-II", consists of 124 YAC detectors with coverage about 500 m$^2$. The inner 100 detectors of 80 cm $\\times $ 50 cm each are deployed in a 10 $\\times$ 10 matrix from with a 1.9 m separation and the outer 24 detectors of 100 cm $\\times$ 50 cm each are distributed around them to reject non-core events whose shower cores are far from the YAC-II array. YAC-II is used to study the primary cosmic-ray composition, in particular, to obtain the energy spectra of proton, helium and iron nuclei between 5$\\times$$10^{13}$ eV and $10^{16}$ eV covering the "knee" and also being connected with direct observations at energies around 100 TeV. We present the design and performance of YAC-II in this paper.

  9. Effect of various solvents on core behavior

    E-Print Network [OSTI]

    Irby, Tom L

    1956-01-01T23:59:59.000Z

    -Section of Core Holder with Core 12 6. Effect of Dri-Film on Sessile Drop Ratios of Kerosene on Silica Crystals in Brine 7. Bar Graph Showing Results of Water Flood Test 8. Plot of Resistivity vs. Brine Saturation for Tests No. 1, 4, 7, 9 and 14 27 9. Plot... Resistance Measurements at Various Brine Saturations For Displacement of Brine with Kerosene 35 III. Electrical Resistance Measurements at Various Brine Saturations for Displacement of Brine with East Texas Crude-Kerosene Mixture 36 ABSTRACT Recently...

  10. Core Values Postcard | The Ames Laboratory

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisitingContract Management Fermi Site Office (FSO) FSOConvertingCopy ServicesCoreCore

  11. 510 Plant Disease / Vol. 97 No. 4 Etiology of Moldy Core, Core Browning, and Core Rot of Fuji Apple in China

    E-Print Network [OSTI]

    Biggs, Alan R.

    Province, 712000, P. R. China; and Alan R. Biggs, Kearneysville Tree Fruit Research and Education Center., Zhang, R., Sun, G. Y., Zha, Y. L., and Biggs, A. R. 2013. Etiology of moldy core, core browning

  12. Fabricating the Solid Core Heatpipe Reactor

    SciTech Connect (OSTI)

    Ring, Peter J.; Sayre, Edwin D. [Advanced Methods and Materials, Inc., 1190 Mountain View-Alviso Road, Suite P, Sunnyvale, CA 94089 (United States); Houts, Mike [NASA Marshall Space Flight Center, Huntsville, Alabama 35812 (United States)

    2006-01-20T23:59:59.000Z

    The solid core heatpipe nuclear reactor has the potential to be the most dependable concept for the nuclear space power system. The design of the conversion system employed permits multiple failure modes instead of the single failure mode of other concepts. Regardless of the material used for the reactor, either stainless steel, high-temperature alloys, Nb1Zr, Tantalum Alloys or MoRe Alloys, making the solid core by machining holes in a large diameter billet is not satisfactory. This is because the large diameter billet will have large grains that are detrimental to the performance of the reactor due to grain boundary diffusion. The ideal fabrication method for the solid core is by hot isostatic pressure diffusion bonding (HIPing). By this technique, wrought fine-grained tubes of the alloy chosen are assembled into the final shape with solid cusps and seal welded so that there is a vacuum in between all surfaces to be diffusion bonded. This welded structure is then HIPed for diffusion bonding. A solid core made of Type 321 stainless steel has been satisfactorily produced by Advanced Methods and Materials and is undergoing evaluation by NASA Marshall Space Flight Center.

  13. UW-Milwaukee Strategic Planning Core Team

    E-Print Network [OSTI]

    Saldin, Dilano

    UW-Milwaukee Strategic Planning Core Team MINUTES Wednesday, February 13, 2013 Lubar Hall, N440, 9 a.m. 1. Welcome 2. Finalized Thematic Team memberships Thematic Team members were identified with the student association to identify potential students to serve on the Thematic teams. 3. Updates

  14. Power excursion analysis for high burnup cores

    SciTech Connect (OSTI)

    Diamond, D.J.; Neymotin, L.; Kohut, P. [Brookhaven National Lab., Upton, NY (United States)

    1996-02-01T23:59:59.000Z

    A study was undertaken of power excursions in high burnup cores. There were three objectives in this study. One was to identify boiling water reactor (BWR) and pressurized water reactor (PWR) transients in which there is significant energy deposition in the fuel. Another was to analyze the response of BWRs to the rod drop accident (RDA) and other transients in which there is a power excursion. The last objective was to investigate the sources of uncertainty in the RDA analysis. In a boiling water reactor, the events identified as having significant energy deposition in the fuel were a rod drop accident, a recirculation flow control failure, and the overpressure events; in a pressurized water reactor, they were a rod ejection accident and boron dilution events. The RDA analysis was done with RAMONA-4B, a computer code that models the space- dependent neutron kinetics throughout the core along with the thermal hydraulics in the core, vessel, and steamline. The results showed that the calculated maximum fuel enthalpy in high burnup fuel will be affected by core design, initial conditions, and modeling assumptions. The important uncertainties in each of these categories are discussed in the report.

  15. Interactive Termination Proofs using Termination Cores

    E-Print Network [OSTI]

    Manolios, Panagiotis "Pete"

    Interactive Termination Proofs using Termination Cores Panagiotis Manolios and Daron Vroon College@ccs.neu.edu, daron.vroon@gmail.com Abstract. Recent advances in termination analysis have yielded new methods and determining how to proceed. In this paper, we address the issue of building termination analysis engines

  16. Convective cores in galactic cooling flows

    E-Print Network [OSTI]

    A. Kritsuk; T. Plewa; E. Mueller

    2001-05-02T23:59:59.000Z

    We use hydrodynamic simulations with adaptive grid refinement to study the dependence of hot gas flows in X-ray luminous giant elliptical galaxies on the efficiency of heat supply to the gas. We consider a number of potential heating mechanisms including Type Ia supernovae and sporadic nuclear activity of a central supermassive black hole. As a starting point for this research we use an equilibrium hydrostatic recycling model (Kritsuk 1996). We show that a compact cooling inflow develops, if the heating is slightly insufficient to counterbalance radiative cooling of the hot gas in the central few kiloparsecs. An excessive heating in the centre, instead, drives a convectively unstable outflow. We model the onset of the instability and a quasi-steady convective regime in the core of the galaxy in two-dimensions assuming axial symmetry. Provided the power of net energy supply in the core is not too high, the convection remains subsonic. The convective pattern is dominated by buoyancy driven large-scale mushroom-like structures. Unlike in the case of a cooling inflow, the X-ray surface brightness of an (on average) isentropic convective core does not display a sharp maximum at the centre. A hybrid model, which combines a subsonic peripheral cooling inflow with an inner convective core, appears to be stable. We also discuss observational implications of these results.

  17. Magnetic Fields in Quasar Cores II

    E-Print Network [OSTI]

    G. B. Taylor

    1999-11-22T23:59:59.000Z

    Multi-frequency polarimetry with the Very Long Baseline Array (VLBA) telescope has revealed absolute Faraday Rotation Measures (RMs) in excess of 1000 rad/m/m in the central regions of 7 out of 8 strong quasars studied (e.g., 3C 273, 3C 279, 3C 395). Beyond a projected distance of ~20 pc, however, the jets are found to have |RM| < 100 rad/m/m. Such sharp RM gradients cannot be produced by cluster or galactic-scale magnetic fields, but rather must be the result of magnetic fields organized over the central 1-100 pc. The RMs of the sources studied to date and the polarization properties of BL Lacs, quasars and galaxies are shown to be consistent so far with the predictions of unified schemes. The direct detection of high RMs in these quasar cores can explain the low fractional core polarizations usually observed in quasars at centimeter wavelengths as the result of irregularities in the Faraday screen on scales smaller than the telescope beam. Variability in the RM of the core is reported for 3C 279 between observations taken 1.5 years apart, indicating that the Faraday screen changes on that timescale, or that the projected superluminal motion of the inner jet components samples a new location in the screen with time. Either way, these changes in the Faraday screen may explain the dramatic variability in core polarization properties displayed by quasars.

  18. Positron annihilation with core and valence electrons

    E-Print Network [OSTI]

    Green, D G

    2015-01-01T23:59:59.000Z

    $\\gamma$-ray spectra for positron annihilation with the core and valence electrons of the noble gas atoms Ar, Kr and Xe is calculated within the framework of diagrammatic many-body theory. The effect of positron-atom and short-range positron-electron correlations on the annihilation process is examined in detail. Short-range correlations, which are described through non-local corrections to the vertex of the annihilation amplitude, are found to significantly enhance the spectra for annihilation on the core orbitals. For Ar, Kr and Xe, the core contributions to the annihilation rate are found to be 0.55\\%, 1.5\\% and 2.2\\% respectively, their small values reflecting the difficulty for the positron to probe distances close to the nucleus. Importantly however, the core subshells have a broad momentum distribution and markedly contribute to the annihilation spectra at Doppler energy shifts $\\gtrsim3$\\,keV, and even dominate the spectra of Kr and Xe at shifts $\\gtrsim5$\\,keV. Their inclusion brings the theoretical ...

  19. Core-mantle interactions for Mercury

    E-Print Network [OSTI]

    Lemaitre, B Noyelles J Dufey A

    2010-01-01T23:59:59.000Z

    Mercury is the target of two space missions: MESSENGER (NASA) which orbit insertion is planned for March 2011, and ESA/JAXA BepiColombo, that should be launched in 2014. Their instruments will observe the surface of the planet with a high accuracy (about 1 arcsec for BepiColombo), what motivates studying its rotation. Mercury is assumed to be composed of a rigid mantle and an at least partially molten core. We here study the influence of the core-mantle interactions on the rotation perturbed by the solar gravitational interaction, by modeling the core as an ellipsoidal cavity filled with inviscid fluid of constant uniform density and vorticity. We use both analytical (Lie transforms) and numerical tools to study this rotation, with different shapes of the core. We express in particular the proper frequencies of the system, because they characterize the response of Mercury to the different solicitations, due to the orbital motion of Mercury around the Sun. We show that the longitudinal motion of Mercury is not...

  20. IS ACTIVE REGION CORE VARIABILITY AGE DEPENDENT?

    SciTech Connect (OSTI)

    Ugarte-Urra, Ignacio [College of Science, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States); Warren, Harry P. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States)

    2012-12-10T23:59:59.000Z

    The presence of both steady and transient loops in active region cores has been reported from soft X-ray and extreme-ultraviolet observations of the solar corona. The relationship between the different loop populations, however, remains an open question. We present an investigation of the short-term variability of loops in the core of two active regions in the context of their long-term evolution. We take advantage of the nearly full Sun observations of STEREO and Solar Dynamics Observatory spacecraft to track these active regions as they rotate around the Sun multiple times. We then diagnose the variability of the active region cores at several instances of their lifetime using EIS/Hinode spectral capabilities. We inspect a broad range of temperatures, including for the first time spatially and temporally resolved images of Ca XIV and Ca XV lines. We find that the active region cores become fainter and steadier with time. The significant emission measure at high temperatures that is not correlated with a comparable increase at low temperatures suggests that high-frequency heating is viable. The presence, however, during the early stages, of an enhanced emission measure in the ''hot'' (3.0-4.5 MK) and ''cool'' (0.6-0.9 MK) components suggests that low-frequency heating also plays a significant role. Our results explain why there have been recent studies supporting both heating scenarios.

  1. CT Scans of Cores Metadata, Barrow, Alaska 2015

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

    Katie McKnight; Tim Kneafsey; Craig Ulrich

    Individual ice cores were collected from Barrow Environmental Observatory in Barrow, Alaska, throughout 2013 and 2014. Cores were drilled along different transects to sample polygonal features (i.e. the trough, center and rim of high, transitional and low center polygons). Most cores were drilled around 1 meter in depth and a few deep cores were drilled around 3 meters in depth. Three-dimensional images of the frozen cores were constructed using a medical X-ray computed tomography (CT) scanner. TIFF files can be uploaded to ImageJ (an open-source imaging software) to examine soil structure and densities within each core.

  2. Cold Molecular Gas as a Possible Component of Dark Matter in the Outer Parts of Disk Galaxies

    E-Print Network [OSTI]

    Ronald J. Allen; Rosa Diaz-Miller

    2004-03-16T23:59:59.000Z

    In the last few years new evidence has been presented for the presence of ongoing massive star formation in the outer HI disks of galaxies. These discoveries strongly suggest that precursor molecular gas must also be present in some physical state which is escaping detection by the usual means (CO(1-0), IR, etc.). We present a model for such a gas in a framework which views the HI as the result of an ongoing ``photodissociation dust grain reformation'' equilibrium in a cold, clumpy molecular medium with a small area filling factor.

  3. Analysis of core samples from the BPXA-DOE-USGS Mount Elbert gas hydrate stratigraphic test well: Insights into core disturbance and handling

    E-Print Network [OSTI]

    Kneafsey, Timothy J.

    2010-01-01T23:59:59.000Z

    Mount Elbert Well) during drilling and coring operationsWell in February 2007. Coring was performed while using a custom oil-based drillingWell, pressure coring was not used, thus the core was depressurized upon ascent. Drilling

  4. A STUDY OF A FAILED CORONAL MASS EJECTION CORE ASSOCIATED WITH AN ASYMMETRIC FILAMENT ERUPTION

    SciTech Connect (OSTI)

    Joshi, Navin Chandra; Srivastava, Abhishek K.; Uddin, Wahab; Kayshap, Pradeep [Aryabhatta Research Institute of Observational Sciences (ARIES), Manora Peak, Nainital-263 002 (India); Filippov, Boris [Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation, Russian Academy of Sciences, Troitsk, Moscow (Russian Federation); Chandra, Ramesh, E-mail: navin@aries.res.in, E-mail: njoshi98@gmail.com, E-mail: aks@aries.res.in [Department of Physics, D.S.B. Campus, Kumaun University, Nainital-263 002, Uttarakhand (India)

    2013-07-01T23:59:59.000Z

    We present multi-wavelength observations of an asymmetric filament eruption and associated coronal mass ejection (CME) and coronal downflows on 2012 June 17 and 18 from 20:00-05:00 UT. We use SDO/AIA and STEREO-B/SECCHI observations to understand the filament eruption scenario and its kinematics, while LASCO C2 observations are analyzed to study the kinematics of the CME and associated downflows. SDO/AIA limb observations show that the filament exhibits a whipping-like asymmetric eruption. STEREO/EUVI disk observations reveal a two-ribbon flare underneath the southeastern part of the filament that most probably occurred due to reconnection processes in the coronal magnetic field in the wake of the filament eruption. The whipping-like filament eruption later produces a slow CME in which the leading edge and the core propagate, with an average speed of Almost-Equal-To 540 km s{sup -1} and Almost-Equal-To 126 km s{sup -1}, respectively, as observed by the LASCO C2 coronagraph. The CME core formed by the eruptive flux rope shows outer coronal downflows with an average speed of Almost-Equal-To 56 km s{sup -1} after reaching Almost-Equal-To 4.33 R{sub Sun }. Initially, the core decelerates at Almost-Equal-To 48 m s{sup -2}. The plasma first decelerates gradually up to a height of Almost-Equal-To 4.33 R{sub Sun} and then starts accelerating downward. We suggest a self-consistent model of a magnetic flux rope representing the magnetic structure of the CME core formed by an eruptive filament. This rope loses its previous stable equilibrium when it reaches a critical height. With some reasonable parameters, and inherent physical conditions, the model describes the non-radial ascending motion of the flux rope in the corona, its stopping at some height, and thereafter its downward motion. These results are in good agreement with observations.

  5. Differential stoichiometry among core ribosomal proteins

    E-Print Network [OSTI]

    Nikolai Slavov; Sefan Semrau; Edoardo Airoldi; Bogdan Budnik; Alexander van Oudenaarden

    2015-04-15T23:59:59.000Z

    Understanding the regulation and structure of ribosomes is essential to understanding protein synthesis and its deregulation in disease. While ribosomes are believed to have a fixed stoichiometry among their core ribosomal proteins (RPs), some experiments suggest a more variable composition. Testing such variability requires direct and precise quantification of RPs. We used mass-spectrometry to directly quantify RPs across monosomes and polysomes of mouse embryonic stem cells (ESC) and budding yeast. Our data show that the stoichiometry among core RPs in wild-type yeast cells and ESC depends both on the growth conditions and on the number of ribosomes bound per mRNA. Furthermore, we find that the fitness of cells with a deleted RP-gene is inversely proportional to the enrichment of the corresponding RP in polysomes. Together, our findings support the existence of ribosomes with distinct protein composition and physiological function.

  6. The core structure of presolar graphite onions

    E-Print Network [OSTI]

    P. Fraundorf; Martin Wackenhut

    2001-10-28T23:59:59.000Z

    Of the ``presolar particles'' extracted from carbonaceous chondrite dissolution residues, i.e. of those particles which show isotopic evidence of solidification in the neighborhood of other stars prior to the origin of our solar system, one subset has an interesting concentric graphite-rim/graphene-core structure. We show here that single graphene sheet defects in the onion cores (e.g. cyclopentane loops) may be observable edge-on by HREM. This could allow a closer look at models for their formation, and in particular strengthen the possibility that growth of these assemblages proceeds atom-by-atom with the aid of such in-plane defects, under conditions of growth (e.g. radiation fluxes or grain temperature) which discourage the graphite layering that dominates subsequent formation of the rim.

  7. MOX fuel arrangement for nuclear core

    DOE Patents [OSTI]

    Kantrowitz, M.L.; Rosenstein, R.G.

    1998-10-13T23:59:59.000Z

    In order to use up a stockpile of weapons-grade plutonium, the plutonium is converted into a mixed oxide (MOX) fuel form wherein it can be disposed in a plurality of different fuel assembly types. Depending on the equilibrium cycle that is required, a predetermined number of one or more of the fuel assembly types are selected and arranged in the core of the reactor in accordance with a selected loading schedule. Each of the fuel assemblies is designed to produce different combustion characteristics whereby the appropriate selection and disposition in the core enables the resulting equilibrium cycle to closely resemble that which is produced using urania fuel. The arrangement of the MOX rods and burnable absorber rods within each of the fuel assemblies, in combination with a selective control of the amount of plutonium which is contained in each of the MOX rods, is used to tailor the combustion characteristics of the assembly. 38 figs.

  8. MOX fuel arrangement for nuclear core

    DOE Patents [OSTI]

    Kantrowitz, Mark L. (Portland, CT); Rosenstein, Richard G. (Windsor, CT)

    1998-01-01T23:59:59.000Z

    In order to use up a stockpile of weapons-grade plutonium, the plutonium is converted into a mixed oxide (MOX) fuel form wherein it can be disposed in a plurality of different fuel assembly types. Depending on the equilibrium cycle that is required, a predetermined number of one or more of the fuel assembly types are selected and arranged in the core of the reactor in accordance with a selected loading schedule. Each of the fuel assemblies is designed to produce different combustion characteristics whereby the appropriate selection and disposition in the core enables the resulting equilibrium cycle to closely resemble that which is produced using urania fuel. The arrangement of the MOX rods and burnable absorber rods within each of the fuel assemblies, in combination with a selective control of the amount of plutonium which is contained in each of the MOX rods, is used to tailor the combustion characteristics of the assembly.

  9. Mox fuel arrangement for nuclear core

    DOE Patents [OSTI]

    Kantrowitz, Mark L. (Portland, CT); Rosenstein, Richard G. (Windsor, CT)

    2001-05-15T23:59:59.000Z

    In order to use up a stockpile of weapons-grade plutonium, the plutonium is converted into a mixed oxide (MOX) fuel form wherein it can be disposed in a plurality of different fuel assembly types. Depending on the equilibrium cycle that is required, a predetermined number of one or more of the fuel assembly types are selected and arranged in the core of the reactor in accordance with a selected loading schedule. Each of the fuel assemblies is designed to produce different combustion characteristics whereby the appropriate selection and disposition in the core enables the resulting equilibrium cycle to closely resemble that which is produced using urania fuel. The arrangement of the MOX rods and burnable absorber rods within each of the fuel assemblies, in combination with a selective control of the amount of plutonium which is contained in each of the MOX rods, is used to tailor the combustion. characteristics of the assembly.

  10. MOX fuel arrangement for nuclear core

    DOE Patents [OSTI]

    Kantrowitz, Mark L. (Portland, CT); Rosenstein, Richard G. (Windsor, CT)

    2001-07-17T23:59:59.000Z

    In order to use up a stockpile of weapons-grade plutonium, the plutonium is converted into a mixed oxide (MOX) fuel form wherein it can be disposed in a plurality of different fuel assembly types. Depending on the equilibrium cycle that is required, a predetermined number of one or more of the fuel assembly types are selected and arranged in the core of the reactor in accordance with a selected loading schedule. Each of the fuel assemblies is designed to produce different combustion characteristics whereby the appropriate selection and disposition in the core enables the resulting equilibrium cycle to closely resemble that which is produced using urania fuel. The arrangement of the MOX rods and burnable absorber rods within each of the fuel assemblies, in combination with a selective control of the amount of plutonium which is contained in each of the MOX rods, is used to tailor the combustion characteristics of the assembly.

  11. Resilient Core Networks for Energy Distribution

    SciTech Connect (OSTI)

    Kuntze, Nicolai; Rudolph, Carsten; Leivesley, Sally; Manz, David O.; Endicott-Popovsky, Barbara E.

    2014-07-28T23:59:59.000Z

    Abstract—Substations and their control are crucial for the availability of electricity in today’s energy distribution. Ad- vanced energy grids with Distributed Energy Resources require higher complexity in substations, distributed functionality and communication between devices inside substations and between substations. Also, substations include more and more intelligent devices and ICT based systems. All these devices are connected to other systems by different types of communication links or are situated in uncontrolled environments. Therefore, the risk of ICT based attacks on energy grids is growing. Consequently, security measures to counter these risks need to be an intrinsic part of energy grids. This paper introduces the concept of a Resilient Core Network to interconnected substations. This core network provides essen- tial security features, enables fast detection of attacks and allows for a distributed and autonomous mitigation of ICT based risks.

  12. Assessment of CRBR core disruptive accident energetics

    SciTech Connect (OSTI)

    Theofanous, T.G.; Bell, C.R.

    1984-03-01T23:59:59.000Z

    The results of an independent assessment of core disruptive accident energetics for the Clinch River Breeder Reactor are presented in this document. This assessment was performed for the Nuclear Regulatory Commission under the direction of the CRBR Program Office within the Office of Nuclear Reactor Regulation. It considered in detail the accident behavior for three accident initiators that are representative of three different classes of events; unprotected loss of flow, unprotected reactivity insertion, and protected loss of heat sink. The primary system's energetics accommodation capability was realistically, yet conservatively, determined in terms of core events. This accommodation capability was found to be equivalent to an isentropic work potential for expansion to one atmosphere of 2550 MJ or a ramp rate of about 200 $/s applied to a classical two-phase disassembly.

  13. Thomson scattering for core plasma on DEMO

    SciTech Connect (OSTI)

    Mukhin, E. E.; Kurskiev, G. S.; Tolstyakov, S. Yu.; Bukreev, I. M.; Chernakov, P. V.; Kochergin, M. M.; Koval, A. N.; Litvinov, A. E.; Masyukevich, S. V.; Razdobarin, A. G.; Semenov, V. V. [Ioffe Physical Technical Institute, 26 Polytechnicheskaya St., St. Petersburg (Russian Federation); Kukushkin, A. B.; Sdvizhenskii, P. A. [NRC Kurchatov Institute, 1, Akademika Kurchatova pl., Moscow, 123182 (Russian Federation); Andrew, P. [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul Lez Durance (France)

    2014-08-21T23:59:59.000Z

    This paper describes the challenges of Thomson scattering implementation for core plasma on DEMO and evaluates the capability to measure extremely high electron temperature range 0.5-40keV. A number of solutions to be developed for ITER diagnostics are suggested in consideration of their realization for DEMO. New approaches suggested for DEMO may also be of interest to ITER and currently operating magnetic confinement devices.

  14. Core/Multishell Nanowire Heterostructures as Multicolor,

    E-Print Network [OSTI]

    Li, Yat

    of dislocations originating from lattice mismatch between GaN and a planar growth substrate. Second, alloys of III by metal-organic chemical vapor deposition with an n-GaN core and InxGa1-xN/GaN/p-AlGaN/p-GaN shells, where controlled during synthesis. Electrical measurements show that the p-AlGaN/p-GaN shell structure yields

  15. DOE GIS core team - a best practice

    SciTech Connect (OSTI)

    Bollinger, J. (James); Bhaduri, Budhendra; Bleakly, D. R. (Denise R.); Brady-Sabeff, Liz; Guber, Al; Guziel, K. A.; Hargrove, Susan; Lee, J. (John); Lee, R. (Randy); Mickus, Kurt; Morehouse, David; Moore, K. (Kevin); Ramsdell, Amy; Rich, P. M. (Paul M.)

    2004-01-01T23:59:59.000Z

    Large government organizations such as the Department of Energy (DOE) are challenged with identifying and implementing best geospatial information management practices to ensure that operational needs are met and government objectives are achieved. Geographic Information System (GIS) professionals, complex wide within the Department, conduct spatial information management practices on a daily basis to complete a wide variety of science and engineering tasks. The DOE Office of the CIO recognized the wealth of geospatial information management knowledge within the DOE complex and formed the DOE GIS Core Team in 2001 as a result. The team is comprised of GIS experts-representing all major DOE labs, site facilities, and programs-who volunteer their time to address issues impacting the entire complex. These include the President's management agenda (with emphasis on the Geospatial One-Stop), homeland security, emergency response, site management, software and geospatial data licensing, and federal, national, and international standards governing the creation and dissemination of geospatial data. The strength of the DOE GIS Core Team is the wide diversity of GIS and scientific expertise represented on the team, which allows it to provide the DOE CIO's office with sound guidance on complex wide issues from a GIS practitioner's perspective. The Core Team's mission is 'to foster technical excellence and communication, to identify and advocate best business practices, and to provide sound recommendations on policy and standards.' As a first step toward identifying best practices the feam conducted a survey of all known GIS assets across the DOE complex. The survey identified each site's GIS expertise, operating systems architecture and software applications, major project areas supported, and a number of other metrics important to the operation of a GIS organization. Results of the survey will be discussed, along with the mission of the Core Team. A broad overview of best practices utilized by many of the leading GIS organizations across the complex will also be provided.

  16. CORE BUSINESS COURSES ACCT 210 ACCOUNTING CR

    E-Print Network [OSTI]

    Shihadeh, Alan

    P.O.Box: CORE BUSINESS COURSES ACCT 210 ACCOUNTING CR ACCT 215 ACCT 217 to ACCT 250 3 BUSS 200 ACCT 217 to ACCT 250 3 BUSS 211 ACCT 217 to ACCT 250 3 BUSS 230 ACCT 217 to ACCT 250 3 BUSS 239 Any business elective 3 BUSS 240 Total Crs 15 BUSS 245 BIDS CR BUSS 248 INFO 205 3 BUSS 249 DCSN 205 3 DCSN 200

  17. Armored spring-core superconducting cable and method of construction

    DOE Patents [OSTI]

    McIntyre, Peter M. (611 Montclair, College Station, TX 77840); Soika, Rainer H. (1 Hensel, #X4C, College Station, TX 77840)

    2002-01-01T23:59:59.000Z

    An armored spring-core superconducting cable (12) is provided. The armored spring-core superconducting cable (12) may include a spring-core (20), at least one superconducting strand (24) wound onto the spring-core (20), and an armored shell (22) that encases the superconducting strands (24). The spring-core (20) is generally a perforated tube that allows purge gases and cryogenic liquids to be circulated through the armored superconducting cable (12), as well as managing the internal stresses within the armored spring-core superconducting cable (12). The armored shell (22) manages the external stresses of the armored spring-core superconducting cable (12) to protect the fragile superconducting strands (24). The armored spring-core superconducting cable (12) may also include a conductive jacket (34) formed outwardly of the armored shell (22).

  18. Clocking the Rise and Fall of Core-Collapse Supernovae

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

    The Rise and Fall of Core-Collapse Supernovae The Rise and Fall of Core-Collapse Supernovae 2D and 3D Models Shed New Light on What Fuels an Exploding Star July 2, 2015 | Tags:...

  19. aml1 core site: Topics by E-print Network

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

    but also helps improve the QoS of the core network and saves the carriers' OPEX and CAPEX on their core networks. Ouyang, Ye; 10.5121ijngn.2010.2105 2010-01-01 6...

  20. arabidopsis core cell: Topics by E-print Network

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

    but also helps improve the QoS of the core network and saves the carriers' OPEX and CAPEX on their core networks. Ouyang, Ye; 10.5121ijngn.2010.2105 2010-01-01 53 Systematic...

  1. Biomarkers Core Lab Price List Does NOT Include

    E-Print Network [OSTI]

    Grishok, Alla

    v3102014 Biomarkers Core Lab Price List Does NOT Include Kit Cost PURCHASED by INVESTIGATOR/1/2013 Page 1 of 5 #12;Biomarkers Core Lab Price List Does NOT Include Kit Cost PURCHASED by INVESTIGATOR

  2. Au34-: A Fluxional Core-Shell Cluster. | EMSL

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

    Au34-: A Fluxional Core-Shell Cluster. Au34-: A Fluxional Core-Shell Cluster. Abstract: Among the large Aun – clusters for n > 20, the photoelectron spectra of Au34...

  3. annular core research reactor: Topics by E-print Network

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

    261 DIRECT EXPERIMENTAL TESTS AND COMPARISON BETWEEN SUB-MINIATURE FISSION CHAMBERS AND SPND FOR FIXED IN-CORE INSTRUMENTATION OF LWR CiteSeer Summary: A fixed in-core...

  4. STRUCTURE OF THE SUN'S CORE: EVOLUTIONAL AND SEISMOLOGICAL CONSTRAINTS

    E-Print Network [OSTI]

    ­generating core where the thermonuclear reactions are significant; there is definitely variable hydrogen approximate, of course. We set the core's upper boundary at 10 million K assuming that thermonuclear reactions

  5. Ice chemistry in starless molecular cores

    E-Print Network [OSTI]

    Kalvans, Juris

    2015-01-01T23:59:59.000Z

    Starless molecular cores are natural laboratories for interstellar molecular chemistry research. The chemistry of ices in such objects was investigated with a three-phase (gas, surface, and mantle) model. We considered the center part of five starless cores, with their physical conditions derived from observations. The ice chemistry of oxygen, nitrogen, sulfur, and complex organic molecules (COMs) was analyzed. We found that an ice-depth dimension, measured, e.g., in monolayers, is essential for modeling of chemistry in interstellar ices. Particularly, the H2O:CO:CO2:N2:NH3 ice abundance ratio regulates the production and destruction of minor species. It is suggested that photodesorption during core collapse period is responsible for high abundance of interstellar H2O2 and O2H, and other species synthesized on the surface. The calculated abundances of COMs in ice were compared to observed gas-phase values. Smaller activation barriers for CO and H2CO hydrogenation may help explain the production of a number of...

  6. Essential Ingredients in Core-collapse Supernovae

    SciTech Connect (OSTI)

    Hix, William Raphael [ORNL; Lentz, E. J. [University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL); Endeve, Eirik [ORNL; Baird, Mark L [ORNL; Chertkow, Merek A [ORNL; Harris, James A [ORNL; Messer, Bronson [ORNL; Mezzacappa, Anthony [ORNL; Bruenn, S. W. [Florida Atlantic University, Boca Raton; Blondin, J. M. [North Carolina State University

    2014-01-01T23:59:59.000Z

    Marking the inevitable death of a massive star, and the birth of a neutron star or black hole, core-collapse supernovae bring together physics at a wide range in spatial scales, from kilometer-sized hydrodynamic motions (eventually growing to gigameter scale) down to femtometer scale nuclear reactions. Carrying 10$^{44}$ joules of kinetic energy and a rich-mix of newly synthesized atomic nuclei, core-collapse supernovae are the preeminent foundries of the nuclear species which make up ourselves and our solar system. We will discuss our emerging understanding of the convectively unstable, neutrino-driven explosion mechanism, based on increasingly realistic neutrino-radiation hydrodynamic simulations that include progressively better nuclear and particle physics. Recent multi-dimensional models with spectral neutrino transport from several research groups, which slowly develop successful explosions for a range of progenitors, have motivated changes in our understanding of the neutrino reheating mechanism. In a similar fashion, improvements in nuclear physics, most notably explorations of weak interactions on nuclei and the nuclear equation of state, continue to refine our understanding of how supernovae explode. Recent progress on both the macroscopic and microscopic effects that affect core-collapse supernovae are discussed.

  7. Shear viscosity in neutron star cores

    E-Print Network [OSTI]

    P. S. Shternin; D. G. Yakovlev

    2008-08-21T23:59:59.000Z

    We calculate the shear viscosity $\\eta = \\eta_{e\\mu}+\\eta_{n}$ in a neutron star core composed of nucleons, electrons and muons ($\\eta_{e\\mu}$ being the electron-muon viscosity, mediated by collisions of electrons and muons with charged particles, and $\\eta_{n}$ the neutron viscosity, mediated by neutron-neutron and neutron-proton collisions). Deriving $\\eta_{e\\mu}$, we take into account the Landau damping in collisions of electrons and muons with charged particles via the exchange of transverse plasmons. It lowers $\\eta_{e\\mu}$ and leads to the non-standard temperature behavior $\\eta_{e\\mu}\\propto T^{-5/3}$. The viscosity $\\eta_{n}$ is calculated taking into account that in-medium effects modify nucleon effective masses in dense matter. Both viscosities, $\\eta_{e\\mu}$ and $\\eta_{n}$, can be important, and both are calculated including the effects of proton superfluidity. They are presented in the form valid for any equation of state of nucleon dense matter. We analyze the density and temperature dependence of $\\eta$ for different equations of state in neutron star cores, and compare $\\eta$ with the bulk viscosity in the core and with the shear viscosity in the crust.

  8. Gas core nuclear rocket feasibility project

    SciTech Connect (OSTI)

    Howe, S.D.; DeVolder, B.; Thode, L.; Zerkle, D.

    1997-09-01T23:59:59.000Z

    The next giant leap for mankind will be the human exploration of Mars. Almost certainly within the next thirty years, a human crew will brave the isolation, the radiation, and the lack of gravity to walk on and explore the Red planet. However, because the mission distances and duration will be hundreds of times greater than the lunar missions, a human crew will face much greater obstacles and a higher risk than those experienced during the Apollo program. A single solution to many of these obstacles is to dramatically decrease the mission duration by developing a high performance propulsion system. The gas core nuclear rocket (GCNR) has the potential to be such a system. The gas core concept relies on the use of fluid dynamic forces to create and maintain a vortex. The vortex is composed of a fissile material which will achieve criticality and produce high power levels. By radiatively coupling to the surrounding fluids, extremely high temperatures in the propellant and, thus, high specific impulses can be generated. The ship velocities enabled by such performance may allow a 9 month round trip, manned Mars mission to be considered. Alternatively, one might consider slightly longer missions in ships that are heavily shielded against the intense Galactic Cosmic Ray flux to further reduce the radiation dose to the crew. The current status of the research program at the Los Alamos National Laboratory into the gas core nuclear rocket feasibility will be discussed.

  9. Essential ingredients in core-collapse supernovae

    SciTech Connect (OSTI)

    Hix, W. Raphael [Physics Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6354 (United States) [Physics Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6354 (United States); Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200 (United States); Lentz, Eric J.; Chertkow, M. Austin; Harris, J. Austin [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200 (United States)] [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200 (United States); Endeve, Eirik [Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6008 (United States)] [Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6008 (United States); Baird, Mark [Reactor and Nuclear Systems Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6003 (United States)] [Reactor and Nuclear Systems Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6003 (United States); Messer, O. E. Bronson [Physics Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6354 (United States) [Physics Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6354 (United States); Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200 (United States); Center for Computational Sciences, Oak Ridge National Laboratory, Oak Ridge TN 37831-6008 (United States); Mezzacappa, Anthony [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200 (United States) [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200 (United States); Joint Institute for Computational Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6173 (United States); Bruenn, Stephen [Department of Physics, Florida Atlantic University, 777 W Glades Road, Boca Raton, FL 33431-0991 (United States)] [Department of Physics, Florida Atlantic University, 777 W Glades Road, Boca Raton, FL 33431-0991 (United States); Blondin, John [Department of Physics, North Carolina State University, Raleigh, NC 27695-8202 (United States)] [Department of Physics, North Carolina State University, Raleigh, NC 27695-8202 (United States)

    2014-04-15T23:59:59.000Z

    Carrying 10{sup 44} joules of kinetic energy and a rich mix of newly synthesized atomic nuclei, core-collapse supernovae are the preeminent foundries of the nuclear species which make up our solar system and ourselves. Signaling the inevitable death of a massive star, and the birth of a neutron star or black hole, core-collapse supernovae combine physics over a wide range in spatial scales, from kilometer-sized hydrodynamic motions (eventually growing to gigameter scale) down to femtometer-scale nuclear reactions. We will discuss our emerging understanding of the convectively-unstable, neutrino-driven explosion mechanism, based on increasingly realistic neutrino radiation hydrodynamic simulations that include progressively better nuclear and particle physics. Multi-dimensional models with spectral neutrino transport from several research groups, which slowly develop successful explosions for a range of progenitors, have recently motivated changes in our understanding of the neutrino reheating mechanism. In a similar fashion, improvements in nuclear physics, most notably explorations of weak interactions on nuclei and the nuclear equation of state, continue to refine our understanding of the births of neutron stars and the supernovae that result. Recent progress on both the macroscopic and microscopic effects that affect core-collapse supernovae are discussed.

  10. Identification of Human Gene Core Promoters Michael Q. Zhang1

    E-Print Network [OSTI]

    Identification of Human Gene Core Promoters in Silico Michael Q. Zhang1 Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724 USA Identification of the 5 -end of human genes requires--CorePromoter. Our experiments indicate that when given a 1- to 2-kb extended promoter, CorePromoter will correctly

  11. OSCAR Parallelizing Compiler Cooperative Heterogeneous Multi-core Architecture

    E-Print Network [OSTI]

    Kasahara, Hironori

    OSCAR Parallelizing Compiler Cooperative Heterogeneous Multi-core Architecture Akihiro Hayashi,kamiyama,watanabe,takeshi,mase}@kasahara.cs.waseda.ac.jp 1. Background Heterogeneous multi-core architectures, which integrates multiple general purpose CPU, powerful parallelizing compiler for hetero- geneous multi-core architectures is expected. Furthermore

  12. Transforming A Linear Algebra Core to An FFT Accelerator

    E-Print Network [OSTI]

    Batory, Don

    Transforming A Linear Algebra Core to An FFT Accelerator Ardavan Pedram, John McCalpin, Andreas the modifications required to transform a highly-efficient, specialized linear algebra core into an efficient engine computations and propose extensions to the micro-architecture of the baseline linear algebra core. Along

  13. Apollo Rock Reveals Moon Had Molten Core | Universe Additional Resources

    E-Print Network [OSTI]

    Weiss, Benjamin P.

    Apollo Rock Reveals Moon Had Molten Core | Universe Today Subscribe Podcast Home Additional Apollo Rock Reveals Moon Had Molten Core Written by Nancy Atkinson If you're new here, you may want to subscribe to my RSS feed. Thanks for visiting! Apollo Rock Reveals Moon Had Molten Core | Universe Today

  14. Hydrogen issue in Core Collapse Supernovae

    E-Print Network [OSTI]

    A. Elmhamdi; I. J. Danziger; D. Branch; B. Leibundgut

    2006-11-06T23:59:59.000Z

    We discuss results of analyzing a time series of selected photospheric-optical spectra of core collapse supernovae (CCSNe). This is accomplished by means of the parameterized supernovae synthetic spectrum (SSp) code ``SYNOW''. Special attention is addressed to traces of hydrogen at early phases, especially for the stripped-envelope SNe (i.e. SNe Ib-c). A thin low mass hydrogen layer extending to very high ejection velocities above the helium shell, is found to be the most likely scenario for Type Ib SNe.

  15. Multilevel transport solution of LWR reactor cores

    SciTech Connect (OSTI)

    Jose Ignacio Marquez Damian; Cassiano R.E. de Oliveira; HyeonKae Park

    2008-09-01T23:59:59.000Z

    This work presents a multilevel approach for the solution of the transport equation in typical LWR assemblies and core configurations. It is based on the second-order, even-parity formulation of the transport equation, which is solved within the framework provided by the finite element-spherical harmonics code EVENT. The performance of the new solver has been compared with that of the standard conjugate gradient solver for diffusion and transport problems on structured and unstruc-tured grids. Numerical results demonstrate the potential of the multilevel scheme for realistic reactor calculations.

  16. Hunton Group core workshop and field trip

    SciTech Connect (OSTI)

    Johnson, K.S. [ed.

    1993-12-31T23:59:59.000Z

    The Late Ordovician-Silurian-Devonian Hunton Group is a moderately thick sequence of shallow-marine carbonates deposited on the south edge of the North American craton. This rock unit is a major target for petroleum exploration and reservoir development in the southern Midcontinent. The workshop described here was held to display cores, outcrop samples, and other reservoir-characterization studies of the Hunton Group and equivalent strata throughout the region. A field trip was organized to complement the workshop by allowing examination of excellent outcrops of the Hunton Group of the Arbuckle Mountains.

  17. GreenCore Capital | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation, search OpenEI ReferenceJump to: navigation,IISrl Jump to: navigation,GreenCore

  18. VERA Core Physics Benchmark Progression Problems Specifications

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps to Predict4 VARIATIONS IN THEVERA Core Physics

  19. Core File Settings | Argonne Leadership Computing Facility

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power Administration would likeConstitution AndControllingCool MagneticCoos BayCore File Settings

  20. The Hubble Wide Field Camera 3 Test of Surfaces in the Outer Solar System: Spectral Variation on Kuiper Belt Objects

    E-Print Network [OSTI]

    Fraser, Wesley C; Glass, Florian

    2015-01-01T23:59:59.000Z

    Here we present additional photometry of targets observed as part of the Hubble Wide Field Camera 3 Test of Surfaces in the Outer Solar System. 12 targets were re-observed with the Wide Field Camera 3 in optical and NIR wavebands designed to compliment those used during the first visit. Additionally, all observations originally presented by Fraser and Brown (2012) were reanalyzed through the same updated photometry pipeline. A reanalysis of the optical and NIR colour distribution reveals a bifurcated optical colour distribution and only two identifiable spectral classes, each of which occupies a broad range of colours and have correlated optical and NIR colours, in agreement with our previous findings. We report the detection of significant spectral variations on 5 targets which cannot be attributed to photometry errors, cosmic rays, point spread function or sensitivity variations, or other image artifacts capable of explaining the magnitude of the variation. The spectrally variable objects are found to have ...

  1. Crystal Structures of the Outer Membrane Domain of Intimin and Invasin from Enterohemorrhagic E. coli and Enteropathogenic Y. pseudotuberculosis

    SciTech Connect (OSTI)

    Fairman, James W.; Dautin, Nathalie; Wojtowicz, Damian; Liu, Wei; Noinaj, Nicholas; Barnard, Travis J.; Udho, Eshwar; Przytycka, Teresa M.; Cherezov, Vadim; Buchanan, Susan K. (CUA); (Einstein); (NIH); (Scripps)

    2012-12-10T23:59:59.000Z

    Intimins and invasins are virulence factors produced by pathogenic Gram-negative bacteria. They contain C-terminal extracellular passenger domains that are involved in adhesion to host cells and N-terminal {beta} domains that are embedded in the outer membrane. Here, we identify the domain boundaries of an E. coli intimin {beta} domain and use this information to solve its structure and the {beta} domain structure of a Y. pseudotuberculosis invasin. Both {beta} domain structures crystallized as monomers and reveal that the previous range of residues assigned to the {beta} domain also includes a protease-resistant domain that is part of the passenger. Additionally, we identify 146 nonredundant representative members of the intimin/invasin family based on the boundaries of the highly conserved intimin and invasin {beta} domains. We then use this set of sequences along with our structural data to find and map the evolutionarily constrained residues within the {beta} domain.

  2. 1.2 CORE INTERPRETATION AND SEDIMENTOLOGICAL ANALYSIS 1.2.1 Generalized Core Description

    E-Print Network [OSTI]

    Schechter, David S.

    reservoir quality. Carbonate rocks are not very common in the analyzed cores. Lithofacies L2: Shales. Shale infrequently; the black color of these shales is a function of their high organic carbon content. Organics siltstone. This lithofacies is characterized by alternations of light and dark colored fine laminae, each

  3. Fuel Breeding and Core Behavior Analyses on In Core Fuel Management of Water Cooled Thorium Reactors

    SciTech Connect (OSTI)

    Permana, Sidik [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, 2-12-1-N1-17, O-okayama, Meguro-ku, Tokyo 152-8550 (Japan); Department of Physics, Bandung Institute of Technology, Gedung Fisika, Jl. Ganesha 10, Bandung 40132 (Indonesia); Sekimoto, Hiroshi [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, 2-12-1-N1-17, O-okayama, Meguro-ku, Tokyo 152-8550 (Japan); Waris, Abdul; Subhki, Muhamad Nurul [Department of Physics, Bandung Institute of Technology, Gedung Fisika, Jl. Ganesha 10, Bandung 40132 (Indonesia); Ismail, [BAPETEN (Indonesia)

    2010-12-23T23:59:59.000Z

    Thorium fuel cycle with recycled U-233 has been widely recognized having some contributions to improve the water-cooled breeder reactor program which has been shown by a feasible area of breeding and negative void reactivity which confirms that fissile of 233U contributes to better fuel breeding and effective for obtaining negative void reactivity coefficient as the main fissile material. The present study has the objective to estimate the effect of whole core configuration as well as burnup effects to the reactor core profile by adopting two dimensional model of fuel core management. About more than 40 months of cycle period has been employed for one cycle fuel irradiation of three batches fuel system for large water cooled thorium reactors. All position of fuel arrangement contributes to the total core conversion ratio which gives conversion ratio less than unity of at the BOC and it contributes to higher than unity (1.01) at the EOC after some irradiation process. Inner part and central part give the important part of breeding contribution with increasing burnup process, while criticality is reduced with increasing the irradiation time. Feasibility of breeding capability of water-cooled thorium reactors for whole core fuel arrangement has confirmed from the obtained conversion ratio which shows higher than unity. Whole core analysis on evaluating reactivity change which is caused by the change of voided condition has been employed for conservative assumption that 100% coolant and moderator are voided. It obtained always a negative void reactivity coefficient during reactor operation which shows relatively more negative void coefficient at BOC (fresh fuel composition), and it becomes less negative void coefficient with increasing the operation time. Negative value of void reactivity coefficient shows the reactor has good safety properties in relation to the reactivity profile which is the main parameter in term of criticality safety analysis. Therefore, this evaluation has confirmed that breeding condition and negative coefficient can be obtained simultaneously for water-cooled thorium reactor obtains based on the whole core fuel arrangement.

  4. CORRELATING INFALL WITH DEUTERIUM FRACTIONATION IN DENSE CORES

    SciTech Connect (OSTI)

    Schnee, Scott; Brunetti, Nathan; Friesen, Rachel [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Di Francesco, James; Johnstone, Doug; Pon, Andy [National Research Council Canada, Herzberg Institute of Astrophysics, 5071 West Saanich Road Victoria, BC V9E 2E7 (Canada); Caselli, Paola, E-mail: sschnee@nrao.edu [School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT (United Kingdom)

    2013-11-10T23:59:59.000Z

    We present a survey of HCO{sup +} (3-2) observations pointed toward dense cores with previous measurements of N(N{sub 2}D{sup +})/N(N{sub 2}H{sup +}). Of the 26 cores in this survey, 5 show the spectroscopic signature of outward motion, 9 exhibit neither inward nor outward motion, 11 appear to be infalling, and 1 is not detected. We compare the degree of deuterium fractionation with infall velocities calculated from the HCO{sup +} spectra and find that those cores with [D]/[H] > 0.1 are more likely to have the signature of inward motions than cores with smaller [D]/[H] ratios. Infall motions are also much more common in cores with masses exceeding their thermal Jeans masses. The fastest infall velocity measured belongs to one of the two protostellar cores in our survey, L1521F, and the observed motions are typically on the order of the sound speed.

  5. Radio Galaxies in Cooling Cores: Insights from a Complete Sample

    E-Print Network [OSTI]

    J. A. Eilek; F. N. Owen

    2006-12-04T23:59:59.000Z

    We have observed a new, complete, cooling-core sample with the VLA, in order to understand how the massive black hole in the central galaxy interacts with the local cluster plasma. We find that every cooling core is currently being energized by an active radio jet, which has probably been destabilized by its interaction with the cooling core. We argue that current models of cooling-core radio galaxies need to be improved before they can be used to determine the rate at which the jet is heating the cooling core. We also argue that the extended radio haloes we see in many cooling-core clusters need extended, in situ re-energization, which cannot be supplied solely by the central galaxy.

  6. Supernova Seismology: Gravitational Wave Signatures of Rapidly Rotating Core Collapse

    E-Print Network [OSTI]

    Fuller, Jim; Abdikamalov, Ernazar; Ott, Christian

    2015-01-01T23:59:59.000Z

    Gravitational waves (GW) generated during a core-collapse supernova open a window into the heart of the explosion. At core bounce, progenitors with rapid core rotation rates exhibit a characteristic GW signal which can be used to constrain the properties of the core of the progenitor star. We investigate the dynamics of rapidly rotating core collapse, focusing on hydrodynamic waves generated by the core bounce and the GW spectrum they produce. The centrifugal distortion of the rapidly rotating proto-neutron star (PNS) leads to the generation of axisymmetric quadrupolar oscillations within the PNS and surrounding envelope. Using linear perturbation theory, we estimate the frequencies, amplitudes, damping times, and GW spectra of the oscillations. Our analysis provides a qualitative explanation for several features of the GW spectrum and shows reasonable agreement with nonlinear hydrodynamic simulations, although a few discrepancies due to non-linear/rotational effects are evident. The dominant early postbounce...

  7. Turbine component casting core with high resolution region

    DOE Patents [OSTI]

    Kamel, Ahmed; Merrill, Gary B.

    2014-08-26T23:59:59.000Z

    A hollow turbine engine component with complex internal features can include a first region and a second, high resolution region. The first region can be defined by a first ceramic core piece formed by any conventional process, such as by injection molding or transfer molding. The second region can be defined by a second ceramic core piece formed separately by a method effective to produce high resolution features, such as tomo lithographic molding. The first core piece and the second core piece can be joined by interlocking engagement that once subjected to an intermediate thermal heat treatment process thermally deform to form a three dimensional interlocking joint between the first and second core pieces by allowing thermal creep to irreversibly interlock the first and second core pieces together such that the joint becomes physically locked together providing joint stability through thermal processing.

  8. Geologic analysis of Devonian Shale cores

    SciTech Connect (OSTI)

    none,

    1982-02-01T23:59:59.000Z

    Cleveland Cliffs Iron Company was awarded a DOE contract in December 1977 for field retrieval and laboratory analysis of cores from the Devonian shales of the following eleven states: Michigan, Illinois, Indiana, Ohio, New York, Pennsylvania, West Virginia, Maryland, Kentucky, Tennessee and Virginia. The purpose of this project is to explore these areas to determine the amount of natural gas being produced from the Devonian shales. The physical properties testing of the rock specimens were performed under subcontract at Michigan Technological University (MTU). The study also included LANDSAT information, geochemical research, structural sedimentary and tectonic data. Following the introduction, and background of the project this report covers the following: field retrieval procedures; laboratory procedures; geologic analysis (by state); references and appendices. (ATT)

  9. A Core Equilibrium Convergence in a Public Goods Economy

    E-Print Network [OSTI]

    Allouch, N

    A core-equilibrium convergence in a public goods economy? Nizar Allouch Queen Mary University of London School of Economics and Finance n.allouch@qmul.ac.uk April 15, 2010 Abstract This paper shows a core-equilibrium convergence in a public goods... economy where consumers’ preferences display warm glow effects. We demonstrate that if each consumer becomes satiated to other con- sumers’ provision, then as the economy grows large the core shrinks to the set of Edgeworth allocations. Moreover, we show...

  10. Graded core/shell semiconductor nanorods and nanorod barcodes

    DOE Patents [OSTI]

    Alivisatos, A. Paul; Scher, Erik C.; Manna, Liberato

    2013-03-26T23:59:59.000Z

    Graded core/shell semiconductor nanorods and shapped nanorods are disclosed comprising Group II-VI, Group III-V and Group IV semiconductors and methods of making the same. Also disclosed are nanorod barcodes using core/shell nanorods where the core is a semiconductor or metal material, and with or without a shell. Methods of labeling analytes using the nanorod barcodes are also disclosed.

  11. Graded core/shell semiconductor nanorods and nanorod barcodes

    DOE Patents [OSTI]

    Alivisatos, A. Paul (Oakland, CA); Scher, Erik C. (San Francisco, CA); Manna, Liberato (Palo Del Collie, IT)

    2009-05-19T23:59:59.000Z

    Disclosed herein is a graded core/shell semiconductor nanorod having at least a first segment of a core of a Group II-VI, Group III-V or a Group IV semiconductor, a graded shell overlying the core, wherein the graded shell comprises at least two monolayers, wherein the at least two monolayers each independently comprise a Group II-VI, Group III-V or a Group IV semiconductor.

  12. Graded core/shell semiconductor nanorods and nanorod barcodes

    DOE Patents [OSTI]

    Alivisatos, A. Paul (Oakland, CA); Scher, Erik C. (San Francisco, CA); Manna, Liberato (Lecce, IT)

    2010-12-14T23:59:59.000Z

    Graded core/shell semiconductor nanorods and shaped nanorods are disclosed comprising Group II-VI, Group III-V and Group IV semiconductors and methods of making the same. Also disclosed are nanorod barcodes using core/shell nanorods where the core is a semiconductor or metal material, and with or without a shell. Methods of labeling analytes using the nanorod barcodes are also disclosed.

  13. Rapid Characterization of Drill Core and Cutting Mineralogy using...

    Open Energy Info (EERE)

    Characterization of Drill Core and Cutting Mineralogy using Infrared Spectroscopy Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Rapid...

  14. Core excitation effects in the breakup of halo nuclei

    SciTech Connect (OSTI)

    Moro, A. M.; Diego, R. de; Lay, J. A.; Crespo, R.; Johnson, R. C.; Arias, J. M.; Gomez-Camacho, J. [Departamento de FAMN, Universidad de Sevilla, Apartado 1065, E-41080 Sevilla (Spain); Centro de Fisica Nuclear, Universidade de Lisboa, Av. Prof. Gama Pinto 2, 1649-003 Lisboa (Portugal) and Departamento de Fisica, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, Av. Prof. Cavaco Silva, Taguspark (Portugal); Physics Department, University of Surrey, Guildford Surrey, GU2 7XH (United Kingdom); Departamento de FAMN, Universidad de Sevilla, Apartado 1065, E-41080 Sevilla (Spain); Departamento de FAMN, Universidad de Sevilla, Apartado 1065, E-41080 Sevilla (Spain) and Centro Nacional de Aceleradores, Universidad de Sevilla/Junta de Andalucia, E-41092 Sevilla (Spain)

    2012-10-20T23:59:59.000Z

    The role of core excitation in the structure and dynamics of two-body halo nuclei is investigated. We present calculations for the resonant breakup of {sup 11}Be on protons at an incident energy of 63.7 MeV/nucleon, where core excitation effects were shown to be important. To describe the reaction, we use a recently developed extension of the DWBA formalism which incorporates these core excitation effects within the no-recoil approximation. The validity of the no-recoil approximation is also examined by comparing with DWBA calculations which take into account core recoil. In addition, calculations with two different continuum representations are presented and compared.

  15. Physics-based multiscale coupling for full core nuclear reactor...

    Office of Scientific and Technical Information (OSTI)

    multiscale coupling for full core nuclear reactor simulation Numerical simulation of nuclear reactors is a key technology in the quest for improvements in efficiency, safety,...

  16. 2006-7 Alphabetical Listing of Core Courses Area Course

    E-Print Network [OSTI]

    Buehrer, R. Michael

    and Civilization 7 BSE 4394 Water Supply and Sanitation in Developing Countries core2006.xls 1 8/1/2006 #12

  17. Core Holes At Valles Caldera - Sulphur Springs Geothermal Area...

    Open Energy Info (EERE)

    of core holes were drilled from 1984 to 1988 as a part of the Continental Scientific Drilling Program (CSDP) to better understand the stratigraphy, structure, hydrothermal...

  18. Core Holes At Valles Caldera - Redondo Geothermal Area (Goff...

    Open Energy Info (EERE)

    of core holes were drilled from 1984 to 1988 as a part of the Continental Scientific Drilling Program (CSDP) to better understand the stratigraphy, structure, hydrothermal...

  19. annular core research: Topics by E-print Network

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

    Nuclear Technologies Websites Summary: -rod power-density profiles from in-core neutron flux measurements J. Kenneth Shultis? Department is proposed for determining power-density...

  20. PE06 -Beginning & Intermediate Core Training Class Syllabus

    E-Print Network [OSTI]

    PE06 - Beginning & Intermediate Core Training Class Syllabus Instructor: Sandra Marbut Office attendance requirements as outlined on this syllabus 3. Pass midterm examination 4. Submit their final

  1. Core Analysis At Long Valley Caldera Geothermal Area (Pribnow...

    Open Energy Info (EERE)

    to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Core Analysis At Long Valley Caldera Geothermal Area (Pribnow, Et Al., 2003) Exploration Activity...

  2. Core Analysis At Valles Caldera - Sulphur Springs Geothermal...

    Open Energy Info (EERE)

    to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Core Analysis At Valles Caldera - Sulphur Springs Geothermal Area (Ito & Tanaka, 1995) Exploration...

  3. Core Analysis At Fenton Hill HDR Geothermal Area (Brookins &...

    Open Energy Info (EERE)

    to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Core Analysis At Fenton Hill HDR Geothermal Area (Brookins & Laughlin, 1983) Exploration Activity...

  4. Percolation Explains How Earth's Iron Core Formed | Stanford...

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

    history. Earth's present layered structure with a metallic core and an overlying silicate mantle would have required mechanisms to separate iron alloy from a silicate phase....

  5. Super-Resolution Fluorescence Nanoscopy Applied to Image Core...

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

    Super-Resolution Fluorescence Nanoscopy Applied to Image Core-Shell Photoswitching Nanoparticles and their Self-Assemblies . Super-Resolution Fluorescence Nanoscopy Applied to...

  6. Rapid characterization of drill core and cutting mineralogy using...

    Open Energy Info (EERE)

    characterization of drill core and cutting mineralogy using infrared spectroscopy Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Rapid...

  7. Core Analysis At Valles Caldera - Sulphur Springs Geothermal...

    Open Energy Info (EERE)

    of the Valles caldera system. Notes Core samples were waxed upon retrieval to reduce drying and atmospheric alteration, and thermal conductivities were measured at a mean...

  8. apple core rot: Topics by E-print Network

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

    China Biology and Medicine Websites Summary: Province, 712000, P. R. China; and Alan R. Biggs, Kearneysville Tree Fruit Research and Education Center, moldy core was very common in...

  9. Matrix Acidizing Core Flooding Apparatus: Equipment and Procedure Description

    E-Print Network [OSTI]

    Grabski, Elizabeth 1985-

    2012-12-10T23:59:59.000Z

    ..................................................................... 3 1.4 Apparatus Requirements .................................................................................. 4 1.5 Objective and Approach .................................................................................. 7 II... ............................................................................ 10 2.3 Core Holders .................................................................................................. 15 2.4 Overburden Pump .......................................................................................... 17...

  10. Inward shift of outer radiation belt electrons as a function of Dst index and the influence of the solar wind on electron injections

    E-Print Network [OSTI]

    Li, Xinlin

    Inward shift of outer radiation belt electrons as a function of Dst index and the influence of the solar wind on electron injections into the slot region H. Zhao1 and X. Li1 Received 30 July 2012; revised 11 November 2012; accepted 13 November 2012. [1] The radial positioning of radiation belt

  11. 0 1 2 3 4 5 Fig. S1. Core photograph combined with Ca, Mn, Fe counts and Mn/Fe ratio determined by XRF core

    E-Print Network [OSTI]

    Gilli, Adrian

    1. Core photograph combined with Ca, Mn, Fe counts and Mn/Fe ratio determined by XRF core scanning determined by XRF core scanning on core ZH10-19 from Lake Zurich recovered in 135 m water depth (2 m above counts and Mn/Fe ratio determined by XRF core scanning on core ZH10-21 from Lake Zurich recovered in 123

  12. Full Core 3-D Simulation of a Partial MOX LWR Core

    SciTech Connect (OSTI)

    S. Bays; W. Skerjanc; M. Pope

    2009-05-01T23:59:59.000Z

    A comparative analysis and comparison of results obtained between 2-D lattice calculations and 3-D full core nodal calculations, in the frame of MOX fuel design, was conducted. This study revealed a set of advantages and disadvantages, with respect to each method, which can be used to guide the level of accuracy desired for future fuel and fuel cycle calculations. For the purpose of isotopic generation for fuel cycle analyses, the approach of using a 2-D lattice code (i.e., fuel assembly in infinite lattice) gave reasonable predictions of uranium and plutonium isotope concentrations at the predicted 3-D core simulation batch average discharge burnup. However, it was found that the 2-D lattice calculation can under-predict the power of pins located along a shared edge between MOX and UO2 by as much as 20%. In this analysis, this error did not occur in the peak pin. However, this was a coincidence and does not rule out the possibility that the peak pin could occur in a lattice position with high calculation uncertainty in future un-optimized studies. Another important consideration in realistic fuel design is the prediction of the peak axial burnup and neutron fluence. The use of 3-D core simulation gave peak burnup conditions, at the pellet level, to be approximately 1.4 times greater than what can be predicted using back-of-the-envelope assumptions of average specific power and irradiation time.

  13. Nitrogen and Oxygen Abundance Variations in the Outer Ejecta of Eta Carinae: Evidence for Recent Chemical Enrichment

    E-Print Network [OSTI]

    Nathan Smith; Jon A. Morse

    2004-02-20T23:59:59.000Z

    We present optical spectra of the ionized `Outer Ejecta' of Eta Carinae that reveal differences in chemical composition at various positions. In particular, young condensations just outside the dusty Homunculus Nebula show strong nitrogen lines and little or no oxygen -- but farther away, nitrogen lines weaken and oxygen lines become stronger. The observed variations in the apparent N/O ratio may signify either that the various blobs were ejected with different abundances, or more likely, that the more distant condensations are interacting with normal-composition material. The second hypothesis is supported by various other clues involving kinematics and X-ray emission, and would suggest that Eta Car is enveloped in a ``cocoon'' deposited by previous stellar-wind mass loss. In particular, all emission features where we detect strong oxygen lines are coincident with or outside the soft X-ray shell. In either case, the observed abundance variations suggest that Eta Car's ejection of nitrogen-rich material is a recent phenomenon -- taking place in just the last few thousand years. Thus, Eta Carinae may be at a critical stage of evolution when ashes of the CNO cycle have just appeared at its surface. Finally, these spectra reveal some extremely fast nitrogen-rich material, with Doppler velocities up to 3200 km/s, and actual space velocities that may be much higher. This is the fastest material yet seen in Eta Car's nebula, but with unknown projection angles its age is uncertain.

  14. Regulations Related to the Outer Continental Shelf Moratoria and Implications of Not Renewing the Moratoria (released in AEO2009)

    Reports and Publications (EIA)

    2009-01-01T23:59:59.000Z

    From 1982 through 2008, Congress annually enacted appropriations riders prohibiting the Minerals Management Service (MMS) of the U.S. Department of the Interior from conducting activities related to leasing, exploration, and production of oil and natural gas on much of the federal Outer Continental Shelf (OCS). Further, a separate executive ban (originally put in place in 1990 by President George H.W. Bush and later extended by President William J. Clinton through 2012) also prohibited leasing on the OCS, with the exception of the Western Gulf of Mexico, portions of the Central and Eastern Gulf of Mexico, and Alaska. In combination, those actions prohibited drilling along the Atlantic and Pacific coasts, in the eastern Gulf of Mexico, and in portions of the central Gulf of Mexico. The Gulf of Mexico Energy Security Act of 2006 (Public Law 109-432) imposed yet a third ban on drilling through 2022 on tracts in the Eastern Gulf of Mexico that are within 125 miles of Florida, east of a dividing line known as the Military Mission Line, and in the Central Gulf of Mexico within 100 miles of Florida.

  15. PWR core monitoring and simulation during load follow operation

    SciTech Connect (OSTI)

    Beard, C. (Westinghouse Electric Corp., Pittsburgh, PA (USA). Commercial Nuclear Fuel Div.); Winter, M.; Niederer, R. (Commonwealth Edison Co., Zion, IL (USA))

    1989-01-01T23:59:59.000Z

    This paper presents a new operation core support system developed for pressurized water reactors. This system provides an enhanced understanding of the operating core with significant benefits in operational flexibility. It also permits evaluation of alternatives and specific situations that allows for enhanced operation of the unit, which provides benefits in power capability and minimizes potential operational issues.

  16. Abell 1201: a Minor merger at second core passage

    E-Print Network [OSTI]

    Ma, Cheng-Jiun; Nulsen, Paul E J; McNamara, Brian R; Murray, Stephen S; Couch, Warrick J

    2012-01-01T23:59:59.000Z

    We present an analysis of the structures and dynamics of the merging cluster Abell~1201, which has two sloshing cold fronts around a cooling core, and an offset gas core approximately 500kpc northwest of the center. New Chandra and XMM-Newton data reveal a region of enhanced brightness east of the offset core, with breaks in surface brightness along its boundary to the north and east. This is interpreted as a tail of gas stripped from the offset core. Gas in the offset core and the tail is distinguished from other gas at the same distance from the cluster center chiefly by having higher density, hence lower entropy. In addition, the offset core shows marginally lower temperature and metallicity than the surrounding area. The metallicity in the cool core is high and there is an abrupt drop in metallicity across the southern cold front. We interpret the observed properties of the system, including the placement of the cold fronts, the offset core and its tail in terms of a simple merger scenario. The offset cor...

  17. Monday, March 13, 2006 MARS: CORE TO CLOUDS

    E-Print Network [OSTI]

    Rathbun, Julie A.

    with current orbital configurations. We run the model for five years with a northern water ice cap then release Core [#1500] We present new melting data in the system Fe-Ni-S at Martian core pressures, using multi. Clouds, Cap, and Consequences: Outflow Events and Mars Hesperian Climate [#1484] We focus on how outflows

  18. How good are the Common Core Mathematics Standards?

    E-Print Network [OSTI]

    Wu, Hung-Hsi

    the grade 8 CA standards. Rather, there is a trade-off: each does some things that the other doesn't. #12How good are the Common Core Mathematics Standards? Concord, CA October 29, 2012 H. Wu sets of math standards in the nation, maybe the best. Why did it adopt the CCSSM (Common Core State

  19. Vector spectropolarimetry of dark-cored penumbral filaments with Hinode

    E-Print Network [OSTI]

    L. R. Bellot Rubio; S. Tsuneta; K. Ichimoto; Y. Katsukawa; B. W. Lites; S. Nagata; T. Shimizu; R. A. Shine; Y. Suematsu; T. D. Tarbell; A. M. Title; J. C. del Toro Iniesta

    2007-08-21T23:59:59.000Z

    We present spectropolarimetric measurements of dark-cored penumbral filaments taken with Hinode at a resolution of 0.3". Our observations demonstrate that dark-cored filaments are more prominent in polarized light than in continuum intensity. Far from disk center, the Stokes profiles emerging from these structures are very asymmetric and show evidence for magnetic fields of different inclinations along the line of sight, together with strong Evershed flows of at least 6-7 km/s. In sunspots closer to disk center, dark-cored penumbral filaments exhibit regular Stokes profiles with little asymmetries due to the vanishing line-of-sight component of the horizontal Evershed flow. An inversion of the observed spectra indicates that the magnetic field is weaker and more inclined in the dark cores as compared with the surrounding bright structures. This is compatible with the idea that dark-cored filaments are the manifestation of flux tubes carrying hot Evershed flows.

  20. The Aquila prestellar core population revealed by Herschel

    E-Print Network [OSTI]

    Könyves, V; Men'shchikov, A; Schneider, N; Arzoumanian, D; Bontemps, S; Attard, M; Motte, F; Didelon, P; Maury, A; Abergel, A; Ali, B; Baluteau, J -P; Bernard, J -Ph; Cambrésy, L; Cox, P; Di Francesco, J; di Giorgio, A M; Griffin, M J; Hargrave, P; Huang, M; Kirk, J; Li, J Z; Martin, P; Minier, V; Molinari, S; Olofsson, G; Pezzuto, S; Russeil, D; Roussel, H; Saraceno, P; Sauvage, M; Sibthorpe, B; Spinoglio, L; Testi, L; Ward-Thompson, D; White, G; Wilson, C D; Woodcraft, A; Zavagno, A

    2010-01-01T23:59:59.000Z

    The origin and possible universality of the stellar initial mass function (IMF) is a major issue in astrophysics. One of the main objectives of the Herschel Gould Belt Survey is to clarify the link between the prestellar core mass function (CMF) and the IMF. We present and discuss the core mass function derived from Herschel data for the large population of prestellar cores discovered with SPIRE and PACS in the Aquila Rift cloud complex at d ~ 260 pc. We detect a total of 541 starless cores in the entire ~11 deg^2 area of the field imaged at 70-500 micron with SPIRE/PACS. Most of these cores appear to be gravitationally bound, and thus prestellar in nature. Our Herschel results confirm that the shape of the prestellar CMF resembles the stellar IMF, with much higher quality statistics than earlier submillimeter continuum ground-based surveys.

  1. Process to make core-shell structured nanoparticles

    DOE Patents [OSTI]

    Luhrs, Claudia; Phillips, Jonathan; Richard, Monique N

    2014-01-07T23:59:59.000Z

    Disclosed is a process for making a composite material that contains core-shell structured nanoparticles. The process includes providing a precursor in the form of a powder a liquid and/or a vapor of a liquid that contains a core material and a shell material, and suspending the precursor in an aerosol gas to produce an aerosol containing the precursor. In addition, the process includes providing a plasma that has a hot zone and passing the aerosol through the hot zone of the plasma. As the aerosol passes through the hot zone of the plasma, at least part of the core material and at least part of the shell material in the aerosol is vaporized. Vapor that contains the core material and the shell material that has been vaporized is removed from the hot zone of the plasma and allowed to condense into core-shell structured nanoparticles.

  2. Solid oxide fuel cell with monolithic core

    DOE Patents [OSTI]

    McPheeters, C.C.; Mrazek, F.C.

    1988-08-02T23:59:59.000Z

    A solid oxide fuel cell in which fuel and oxidant gases undergo an electrochemical reaction to produce an electrical output includes a monolithic core comprised of a corrugated conductive sheet disposed between upper and lower generally flat sheets. The corrugated sheet includes a plurality of spaced, parallel, elongated slots which form a series of closed, linear, first upper and second lower gas flow channels with the upper and lower sheets within which a fuel gas and an oxidant gas respectively flow. Facing ends of the fuel cell are generally V-shaped and provide for fuel and oxidant gas inlet and outlet flow, respectively, and include inlet and outlet gas flow channels which are continuous with the aforementioned upper fuel gas and lower oxidant gas flow channels. The upper and lower flat sheets and the intermediate corrugated sheet are preferably comprised of ceramic materials and are securely coupled together such as by assembly in the green state and sintering together during firing at high temperatures. A potential difference across the fuel cell, or across a stacked array of similar fuel cells, is generated when an oxidant gas such as air and a fuel such as hydrogen gas is directed through the fuel cell at high temperatures, e.g., between 700 C and 1,100 C. 8 figs.

  3. Advanced High Temperature Reactor Neutronic Core Design

    SciTech Connect (OSTI)

    Ilas, Dan [ORNL] [ORNL; Holcomb, David Eugene [ORNL] [ORNL; Varma, Venugopal Koikal [ORNL] [ORNL

    2012-01-01T23:59:59.000Z

    The AHTR is a 3400 MW(t) FHR class reactor design concept intended to serve as a central generating station type power plant. While significant technology development and demonstration remains, the basic design concept appears sound and tolerant of much of the remaining performance uncertainty. No fundamental impediments have been identified that would prevent widespread deployment of the concept. This paper focuses on the preliminary neutronic design studies performed at ORNL during the fiscal year 2011. After a brief presentation of the AHTR design concept, the paper summarizes several neutronic studies performed at ORNL during 2011. An optimization study for the AHTR core is first presented. The temperature and void coefficients of reactivity are then analyzed for a few configurations of interest. A discussion of the limiting factors due to the fast neutron fluence follows. The neutronic studies conclude with a discussion of the control and shutdown options. The studies presented confirm that sound neutronic alternatives exist for the design of the AHTR to maintain full passive safety features and reasonable operation conditions.

  4. Solid oxide fuel cell with monolithic core

    DOE Patents [OSTI]

    McPheeters, Charles C. (Plainfield, IL); Mrazek, Franklin C. (Hickory Hills, IL)

    1988-01-01T23:59:59.000Z

    A solid oxide fuel cell in which fuel and oxidant gases undergo an electrochemical reaction to produce an electrical output includes a monolithic core comprised of a corrugated conductive sheet disposed between upper and lower generally flat sheets. The corrugated sheet includes a plurality of spaced, parallel, elongated slots which form a series of closed, linear, first upper and second lower gas flow channels with the upper and lower sheets within which a fuel gas and an oxidant gas respectively flow. Facing ends of the fuel cell are generally V-shaped and provide for fuel and oxidant gas inlet and outlet flow, respectively, and include inlet and outlet gas flow channels which are continuous with the aforementioned upper fuel gas and lower oxidant gas flow channels. The upper and lower flat sheets and the intermediate corrugated sheet are preferably comprised of ceramic materials and are securely coupled together such as by assembly in the green state and sintering together during firing at high temperatures. A potential difference across the fuel cell, or across a stacked array of similar fuel cells, is generated when an oxidant gas such as air and a fuel such as hydrogen gas is directed through the fuel cell at high temperatures, e.g., between 700.degree. C. and 1100.degree. C.

  5. CHARACTERIZATION OF CORE SAMPLE COLLECTED FROM THE SALTSTONE DISPOSAL FACILITY

    SciTech Connect (OSTI)

    Cozzi, A.; Duncan, A.

    2010-01-28T23:59:59.000Z

    During the month of September 2008, grout core samples were collected from the Saltstone Disposal Facility, Vault 4, cell E. This grout was placed during processing campaigns in December 2007 from Deliquification, Dissolution and Adjustment Batch 2 salt solution. The 4QCY07 Waste Acceptance Criteria sample collected on 11/16/07 represents the salt solution in the core samples. Core samples were retrieved to initiate the historical database of properties of emplaced Saltstone and to demonstrate the correlation between field collected and laboratory prepared samples. Three samples were collected from three different locations. Samples were collected using a two-inch diameter concrete coring bit. In April 2009, the core samples were removed from the evacuated sample container, inspected, transferred to PVC containers, and backfilled with nitrogen. Samples furthest from the wall were the most intact cylindrically shaped cored samples. The shade of the core samples darkened as the depth of coring increased. Based on the visual inspection, sample 3-3 was selected for all subsequent analysis. The density and porosity of the Vault 4 core sample, 1.90 g/cm{sup 3} and 59.90% respectively, were comparable to values achieved for laboratory prepared samples. X-ray diffraction analysis identified phases consistent with the expectations for hydrated Saltstone. Microscopic analysis revealed morphology features characteristic of cementitious materials with fly ash and calcium silicate hydrate gel. When taken together, the results of the density, porosity, x-ray diffraction analysis and microscopic analysis support the conclusion that the Vault 4, Cell E core sample is representative of the expected waste form.

  6. Outer automorphism groups Dissertation

    E-Print Network [OSTI]

    Braun, Gábor

    Naturwissenschaften von Gábor Braun geboren in Budapest, Ungarn vorgelegt beim Fachbereich Mathematik der Universität

  7. Outer Continental Shelf Production

    Gasoline and Diesel Fuel Update (EIA)

    and public understanding regarding energy and its interaction with the economy and the environment. EIA is the nation's premier source of energy information and, by law, its...

  8. An In-Core Power Deposition and Fuel Thermal Environmental Monitor for Long-Lived Reactor Cores

    SciTech Connect (OSTI)

    Don W. Miller

    2004-09-28T23:59:59.000Z

    The primary objective of this program is to develop the Constant Temperature Power Sensor (CTPS) as in-core instrumentation that will provide a detailed map of local nuclear power deposition and coolant thermal-hydraulic conditions during the entire life of the core.

  9. EVERY BCG WITH A STRONG RADIO AGN HAS AN X-RAY COOL CORE: IS THE COOL CORE-NONCOOL CORE DICHOTOMY TOO SIMPLE?

    SciTech Connect (OSTI)

    Sun, M., E-mail: msun@virginia.ed [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904-4325 (United States)

    2009-10-20T23:59:59.000Z

    The radio active galactic nucleus (AGN) feedback in X-ray cool cores has been proposed as a crucial ingredient in the evolution of baryonic structures. However, it has long been known that strong radio AGNs also exist in 'noncool core' clusters, which brings up the question whether an X-ray cool core is always required for the radio feedback. In this work, we present a systematic analysis of brightest cluster galaxies (BCGs) and strong radio AGNs in 152 groups and clusters from the Chandra archive. All 69 BCGs with radio AGN more luminous than 2 x 10{sup 23} W Hz{sup -1} at 1.4 GHz are found to have X-ray cool cores. BCG cool cores can be divided into two classes: the large cool core (LCC) class and the corona class. Small coronae, easily overlooked at z > 0.1, can trigger strong heating episodes in groups and clusters, long before LCCs are formed. Strong radio outbursts triggered by coronae may destroy embryonic LCCs and thus provide another mechanism to prevent the formation of LCCs. However, it is unclear whether coronae are decoupled from the radio feedback cycles as they have to be largely immune to strong radio outbursts. Our sample study also shows the absence of groups with a luminous cool core while hosting a strong radio AGN, which is not observed in clusters. This points to a greater impact of radio heating on low-mass systems than clusters. Few L {sub 1.4GHz} > 10{sup 24} W Hz{sup -1} radio AGNs (approx16%) host an L {sub 0.5-10keV} > 10{sup 42} erg s{sup -1} X-ray AGN, while above these thresholds, all X-ray AGNs in BCGs are also radio AGNs. As examples of the corona class, we also present detailed analyses of a BCG corona associated with a strong radio AGN (ESO 137-006 in A3627) and one of the faintest coronae known (NGC 4709 in the Centaurus cluster). Our results suggest that the traditional cool core/noncool core dichotomy is too simple. A better alternative is the cool core distribution function, with the enclosed X-ray luminosity or gas mass.

  10. Targeted Protein Degradation of Outer Membrane Decaheme Cytochrome MtrC Metal Reductase in Shewanella oneidensis MR-1 Measured Using Biarsenical Probe CrAsH-EDT2

    SciTech Connect (OSTI)

    Xiong, Yijia; Chen, Baowei; Shi, Liang; Fredrickson, Jim K.; Bigelow, Diana J.; Squier, Thomas C.

    2011-10-14T23:59:59.000Z

    Development of efficient microbial biofuel cells requires an ability to exploit interfacial electron transfer reactions to external electron acceptors, such as metal oxides; such reactions occur in the facultative anaerobic gram-negative bacterium Shewanella oneidensis MR-1 through the catalytic activity of the outer membrane decaheme c-type cytochrome MtrC. Central to the utility of this pathway to synthetic biology is an understanding of cellular mechanisms that maintain optimal MtrC function, cellular localization, and renewal by degradation and resynthesis. In order to monitor trafficking to the outer membrane, and the environmental sensitivity of MtrC, we have engineered a tetracysteine tag (i.e., CCPGCC) at its C-terminus that permits labeling by the cell impermeable biarsenical fluorophore, carboxy-FlAsH (CrAsH) of MtrC at the surface of living Shewanella oneidensis MR-1 cells. In comparison, the cell permeable reagent FlAsH permits labeling of the entire population of MtrC, including proteolytic fragments resulting from incorrect maturation. We demonstrate specific labeling by CrAsH of engineered MtrC which is dependent on the presence of a functional type-2 secretion system (T2S), as evidenced by T2S system gspD or gspG deletion mutants which are incapable of CrAsH labeling. Under these latter conditions, MtrC undergoes proteolytic degradation to form a large 35-38 kDa fragment; this degradation product is also resolved during normal turnover of the CrAsH-labeled MtrC protein. No MtrC protein is released into the medium during turnover, suggesting the presence of cellular turnover systems involving MtrC reuptake and degradation. The mature MtrC localized on the outer membrane is a long-lived protein, with a turnover rate of 0.043 hr-1 that is insensitive to O2 concentration. Maturation of MtrC is relatively inefficient, with substantial rates of turnover of the immature protein prior to export to the outer membrane (i.e., 0.028 hr-1) that are consistent with the inherent complexity associated with correct heme insertion and acylation of MtrC that occurs in the periplasm prior to its targeting to the outer membrane. These latter results suggest that MtrC protein trafficking to the outer membrane and its subsequent degradation are tightly regulated, which is consistent with cellular processing pathways that target MtrC to extracellular structures and their possible role in promoting electron transfer from Shewanella to extracellular acceptors.

  11. Apparatus and method for controlling the temperature of the core of a super-conducting transformer

    SciTech Connect (OSTI)

    Golner, Thomas; Pleva, Edward; Mehta, Shirish

    2006-10-10T23:59:59.000Z

    An apparatus for controlling the temperature of a core of a transformer is provided that includes a core, a shield surrounding the core, a cast formed between the core and the shield, and tubing positioned on the shield. The cast directs heat from the core to the shield and cooling fluid is directed through the tubing to cool the shield.

  12. Silicon and Nickel Enrichment in Planet-Host Stars: Observations and Implications for the Core-Accretion Theory of Planet Formation

    E-Print Network [OSTI]

    Sarah E. Robinson; Gregory Laughlin; Peter Bodenheimer; Debra Fischer

    2006-01-27T23:59:59.000Z

    We present evidence that stars with planets exhibit statistically significant silicon and nickel enrichment over the general metal-rich population. We also present simulations which predict silicon enhancement of planet hosts within the context of the core-accretion hypothesis for giant planet formation. Because silicon and oxygen are both alpha elements, [Si/Fe] traces [O/Fe], so the silicon enhancement in planet hosts predicts that these stars are oxygen-rich as well. We present new numerical simulations of planet formation by core accretion that establish the timescale on which a Jovian planet reaches rapid gas accretion, t_rga, as a function of solid surface density sigma_solid: (t_rga / 1 Myr) = (sigma_solid / 25.0 g cm^{-2})^{-1.44}. This relation enables us to construct Monte Carlo simulations that predict the fraction of star-disk systems that form planets as a function of [Fe/H], [Si/Fe], disk mass, outer disk radius and disk lifetime. Our simulations reproduce both the known planet-metallicity correlation and the planet-silicon correlation reported in this paper. The simulations predict that 16% of Solar-type stars form Jupiter-mass planets, in agreement with 12% predicted from extrapolation of the observed planet frequency-semimajor axis distribution. Although a simple interpretation of core accretion predicts that the planet-silicon correlation should be much stronger than the planet-nickel correlation, we observe the same degree of silicon and nickel enhancement in planet hosts. If this result persists once more planets have been discovered, it might indicate a complexity in the chemistry of planet formation beyond the simple accumulation of solids in the core accretion theory.

  13. On the perspectives of testing the Dvali-Gabadadze-Porrati gravity model with the outer planets of the Solar System

    E-Print Network [OSTI]

    Lorenzo Iorio; Giuseppe Giudice

    2006-07-31T23:59:59.000Z

    The multidimensional braneworld gravity model by Dvali, Gabadadze and Porrati was primarily put forth to explain the observed acceleration of the expansion of the Universe without resorting to dark energy. One of the most intriguing features of such a model is that it also predicts small effects on the orbital motion of test particles which could be tested in such a way that local measurements at Solar System scales would allow to get information on the global properties of the Universe. Lue and Starkman derived a secular extra-perihelion \\omega precession of 5\\times 10^-4 arcseconds per century, while Iorio showed that the mean longitude \\lambda is affected by a secular precession of about 10^-3 arcseconds per century. Such effects depend only on the eccentricities e of the orbits via second-order terms: they are, instead, independent of their semimajor axes a. Up to now, the observational efforts focused on the dynamics of the inner planets of the Solar System whose orbits are the best known via radar ranging. Since the competing Newtonian and Einsteinian effects like the precessions due to the solar quadrupole mass moment J2, the gravitoelectric and gravitomagnetic part of the equations of motion reduce with increasing distances, it would be possible to argue that an analysis of the orbital dynamics of the outer planets of the Solar System, with particular emphasis on Saturn because of the ongoing Cassini mission with its precision ranging instrumentation, could be helpful in evidencing the predicted new features of motion. In this note we investigate this possibility in view of the latest results in the planetary ephemeris field. Unfortunately, the current level of accuracy rules out this appealing possibility and it appears unlikely that Cassini and GAIA will ameliorate the situation.

  14. Heterogeneous-k-core versus Bootstrap Percolation on Complex Networks

    E-Print Network [OSTI]

    G. J. Baxter; S. N. Dorogovtsev; A. V. Goltsev; J. F. F. Mendes

    2010-12-20T23:59:59.000Z

    We introduce the heterogeneous-$k$-core, which generalizes the $k$-core, and contrast it with bootstrap percolation. Vertices have a threshold $k_i$ which may be different at each vertex. If a vertex has less than $k_i$ neighbors it is pruned from the network. The heterogeneous-$k$-core is the sub-graph remaining after no further vertices can be pruned. If the thresholds $k_i$ are $1$ with probability $f$ or $k \\geq 3$ with probability $(1-f)$, the process forms one branch of an activation-pruning process which demonstrates hysteresis. The other branch is formed by ordinary bootstrap percolation. We show that there are two types of transitions in this heterogeneous-$k$-core process: the giant heterogeneous-$k$-core may appear with a continuous transition and there may be a second, discontinuous, hybrid transition. We compare critical phenomena, critical clusters and avalanches at the heterogeneous-$k$-core and bootstrap percolation transitions. We also show that network structure has a crucial effect on these processes, with the giant heterogeneous-$k$-core appearing immediately at a finite value for any $f > 0$ when the degree distribution tends to a power law $P(q) \\sim q^{-\\gamma}$ with $\\gamma < 3$.

  15. One pass core design of a super fast reactor

    SciTech Connect (OSTI)

    Liu, Qingjie; Oka, Yoshiaki [Cooperative Major in Nuclear Energy, Waseda University, Tokyo 169-8555 (Japan)

    2013-07-01T23:59:59.000Z

    One pass core design for Supercritical-pressure light water-cooled fast reactor (Super FR) is proposed. The whole core is cooled with upward flow in one through flow pattern like PWR. Compared with the previous two pass core design; this new flow pattern can significantly simplify the core concept. Upper core structure, coolant flow scheme as well as refueling procedure are as simple as in PWR. In one pass core design, supercritical-pressure water is at approximately 25.0 MPa and enters the core at 280 C. degrees and is heated up in one through flow pattern upwardly to the average outlet temperature of 500 C. degrees. Great density change in vertical direction can cause significant axial power offset during the cycle. Meanwhile, Pu accumulated in the UO{sub 2} fuel blanket assemblies also introduces great power increase during cycle, which requires large amount of flow for heat removal and makes the outlet temperature of blanket low at the beginning of equilibrium cycle (BOEC). To deal with these issues, some MOX fuel is applied in the bottom region of the blanket assembly. This can help to mitigate the power change in blanket due to Pu accumulation and to increase the outlet temperature of the blanket during cycle. Neutron transport and thermohydraulics coupled calculation shows that this design can satisfy the requirement in the Super FR principle for both 500 C. degrees outlet temperature and negative coolant void reactivity. (authors)

  16. A method for reducing encapsulation stress to ferrite pot cores

    SciTech Connect (OSTI)

    Sanchez, R.O.

    1994-08-01T23:59:59.000Z

    This paper describes a method of reducing the mechanical stress caused when a ferrite pot core is encapsulated in a rigid epoxy. the stresses are due to the differences of coefficient of thermal expansion between the two materials. A stress relief medium, phenolic micro-balloon-filled, syntactic polysulfide, is molded into the shape of the pot core. The molded polysulfide is bonded to the core prior to encapsulation. The new package design has made a significant difference in the ability to survive temperature cycles.

  17. Exploiting Symmetry in Integer Convex Optimization using Core Points

    E-Print Network [OSTI]

    Herr, Katrin; Schürmann, Achill

    2012-01-01T23:59:59.000Z

    We consider convex programming problems with integrality constraints that are invariant under a linear symmetry group. We define a core point of such a symmetry group as an integral point for which the convex hull of its orbit does not contain integral points other than the orbit points themselves. These core points allow us to decompose symmetric integer convex programming problems. Especially for symmetric integer linear programs we describe two algorithms based on this decomposition. Using a characterization of core points for direct products of symmetric groups, we show that prototype implementations can compete with state-of-the art commercial solvers and solve an open MIPLIB problem.

  18. Novel stacked folded cores for blast-resistant sandwich beams

    E-Print Network [OSTI]

    Schenk, M.; Guest, S. D.; McShane, G. J.

    2014-08-23T23:59:59.000Z

    the hinge lines is likely to be large, and therefore the material will be susceptible to damage and thermal softening in practice. This would in turn influence the compressive strength of the cellular material. However, we opt to omit these details... depth (Dc) and n2 = 25 along the core length (Lc). There are a total of s = 5 layers across the width of the core (Wc), with n3 = 2 pairs of layers A and B (Fig. 1). For a fixed core envelope, specifying the number of unit cells n1, n2 and n3...

  19. Cool core cycles: Cold gas and AGN jet feedback in cluster cores

    E-Print Network [OSTI]

    Prasad, Deovrat; Babul, Arif

    2015-01-01T23:59:59.000Z

    Using high-resolution 3-D and 2-D (axisymmetric) hydrodynamic simulations in spherical geometry, we study the evolution of cool cluster cores heated by feedback-driven bipolar active galactic nuclei (AGN) jets. Condensation of cold gas, and the consequent enhanced accretion, is required for AGN feedback to balance radiative cooling with reasonable efficiencies, and to match the observed cool core properties. A feedback efficiency (mechanical luminosity $\\approx \\epsilon \\dot{M}_{\\rm acc} c^2$; where $\\dot{M}_{\\rm acc}$ is the mass accretion rate at 1 kpc) as small as $5 \\times 10^{-5}$ is sufficient to reduce the cooling/accretion rate by $\\sim 10$ compared to a pure cooling flow. This value is smaller compared to the ones considered earlier, and is consistent with the jet efficiency and the fact that only a small fraction of gas at 1 kpc is accreted on to the supermassive black hole (SMBH). We find hysteresis cycles in all our simulations with cold mode feedback: {\\em condensation} of cold gas when the ratio...

  20. Impact of Limitations on Access to Oil and Natural Gas Resources in the Federal Outer Continental Shelf (released in AEO2009)

    Reports and Publications (EIA)

    2009-01-01T23:59:59.000Z

    The U.S. offshore is estimated to contain substantial resources of both crude oil and natural gas, but until recently some of the areas of the lower 48 states Outer Continental Shelf (OCS) have been under leasing moratoria. The Presidential ban on offshore drilling in portions of the lower 48 OCS was lifted in July 2008, and the Congressional ban was allowed to expire in September 2008, removing regulatory obstacles to development of the Atlantic and Pacific OCS.

  1. Les populations priurbaines face l'automobile en grande couronne francilienne Population and automobile dependence in the outer suburbs of Paris

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Les populations périurbaines face à l'automobile en grande couronne francilienne Population and automobile dependence in the outer suburbs of Paris Titre courant : les populations périurbaines face à l'automobile se propose d'identifier si l'automobile qui a participé au développement des espaces périurbains et

  2. Cooling curves and initial models for low-mass white dwarfs (<0.25 Msun) with helium core

    E-Print Network [OSTI]

    Marek J. Sarna; Ene Ergma; Jelena Antipova

    2000-02-11T23:59:59.000Z

    We present a detailed calculation of the evolution of low-mass ($< 0.25~M_\\odot $) helium white dwarfs. These white dwarfs (the optical companions to binary millisecond pulsars) are formed via long-term, low-mass binary evolution. After detachment from the Roche lobe, the hot helium cores have a rather thick hydrogen layer with mass between 0.01 to 0.06$~M_\\odot $. Due to mixing between the core and outer envelope, the surface hydrogen content is 0.5 to 0.35, depending on the initial value of the heavy element (Z) and the initial secondary mass. We found that the majority of our computed models experience one or two hydrogen shell flashes. We found that the mass of the helium dwarf in which the hydrogen shell flash occurs depends on the chemical composition. The minimum helium white dwarf mass in which a hydrogen flash takes place is 0.213$~M_\\odot $ (Z=0.003), 0.198$~M_\\odot $ (Z=0.01), 0.192$~M_\\odot $ (Z=0.02) or 0.183$~M_\\odot $ (Z=0.03). The duration of the flashes (independent of chemical composition) is between few $\\times 10^6 $ years to few $\\times 10^7 $ years. In several flashes the white dwarf radius will increase so much that it forces the model to fill its Roche lobe again. Our calculations show that cooling history of the helium white dwarf depends dramatically on the thickness of the hydrogen layer. We show that the transition from a cooling white dwarf with a temporary stable hydrogen-burning shell to a cooling white dwarf in which almost all residual hydrogen is lost in a few thermal flashes (via Roche-lobe overflow) occurs between 0.183-0.213$~M_\\odot $ (depending on the heavy element value).

  3. Characterization of a high-temperature superconducting conductor on round core cables in magnetic fields up to 20 T

    SciTech Connect (OSTI)

    van der Laan, Danko [Advanced Conductor Technologies; Noyes, Patrick [National High Magnetic Field Laboratory; Miller, George [National High Magnetic Field Laboratory; Weijers, Hubertus [National High Magnetic Field Laboratory; Willering, Gerard [CERN

    2013-02-13T23:59:59.000Z

    The next generation of high-field magnets that will operate at magnetic fields substantially above 20 T, or at temperatures substantially above 4.2 K, requires high-temperature superconductors (HTS). Conductor on round core (CORC) cables, in which RE-Ba{sub 2}Cu{sub 3}O{sub 7-{delta}} (RE = rare earth) (REBCO) coated conductors are wound in a helical fashion on a fl?exible core, are a practical and versatile HTS cable option for low-inductance, high-field magnets. We performed the first tests of CORC magnet cables in liquid helium in magnetic fields of up to 20 T. A record critical current I{sub c} of 5021 A was measured at 4.2 K and 19 T. In a cable with an outer diameter of 7.5 mm, this value corresponds to an engineering current density J{sub e} of 114 A mm{sup -2} , the highest J{sub e} ever reported for a superconducting cable at such high magnetic fields. Additionally, the first magnet wound from an HTS cable was constructed from a 6 m-long CORC cable. The 12-turn, double-layer magnet had an inner diameter of 9 cm and was tested in a magnetic field of 20 T, at which it had an I{sub c} of 1966 A. The cables were quenched repetitively without degradation during the measurements, demonstrating the feasibility of HTS CORC cables for use in high-field magnet applications.

  4. Core-Shell Nanopillar Array Solar Cells using Cadmium Sulfide Coating on Indium Phosphide Nanopillars

    E-Print Network [OSTI]

    Tu, Bor-An Clayton

    2013-01-01T23:59:59.000Z

    Yang, “Solution-processed core-shell nanowires for efficientYong, “Fabrication of ZnO/CdS core/shell nanowire arrays fornew fabrication method for core-shell nanopillar array solar

  5. Full Core, Heterogeneous, Time Dependent Neutron Transport Calculations with the 3D Code DeCART

    E-Print Network [OSTI]

    Hursin, Mathieu

    2010-01-01T23:59:59.000Z

    core layout for the 1/8th PWR core model ________________ 76and future of the NEACRP PWR core transient benchmark. 199449. Hursin, M. (2008). PWR Control Rod Ejection Analysis

  6. Ferrite-Cored Solenoidal Induction Coil Sensor for BUD (MM-1667)

    E-Print Network [OSTI]

    Morrison, F.

    2012-01-01T23:59:59.000Z

    following observations: 1) A ferrite-cored solenoidal coilthe same order as L. 2) A ferrite-cored solenoidal coil canstable response. 4) Feedback ferrite-cored solenoidal coils

  7. SPATIAL AND TEMPORAL VARIABILITY OF NET ACCUMULATION FROM SHALLOW CORES FROM

    E-Print Network [OSTI]

    Moore, John

    SPATIAL AND TEMPORAL VARIABILITY OF NET ACCUMULATION FROM SHALLOW CORES FROM VESTFONNA ICE CAP variability of net accumulation from shallow cores from Vestfonna ice cap (Nordaustlandet, Svalbard. We analyse ice cores from Vestfonna ice cap (Nordaustlandet, Svalbard). Oxygen isoto- pic

  8. Cooling, Gravity and Geometry: Flow-driven Massive Core Formation

    E-Print Network [OSTI]

    Fabian Heitsch; Lee Hartmann; Adrianne D. Slyz; Julien E. G. Devriendt; Andreas Burkert

    2007-09-15T23:59:59.000Z

    We study numerically the formation of molecular clouds in large-scale colliding flows including self-gravity. The models emphasize the competition between the effects of gravity on global and local scales in an isolated cloud. Global gravity builds up large-scale filaments, while local gravity -- triggered by a combination of strong thermal and dynamical instabilities -- causes cores to form. The dynamical instabilities give rise to a local focusing of the colliding flows, facilitating the rapid formation of massive protostellar cores of a few 100 M$_\\odot$. The forming clouds do not reach an equilibrium state, though the motions within the clouds appear comparable to ``virial''. The self-similar core mass distributions derived from models with and without self-gravity indicate that the core mass distribution is set very early on during the cloud formation process, predominantly by a combination of thermal and dynamical instabilities rather than by self-gravity.

  9. Core Analysis At Valles Caldera - Sulphur Springs Geothermal...

    Open Energy Info (EERE)

    References Giday WoldeGabriel, Fraser Goff (1992) K-Ar Dates Of Hydrothermal Clays From Core Hole Vc-2B, Valles Caldera, New Mexico And Their Relation To Alteration In A...

  10. Hanging core support system for a nuclear reactor. [LMFBR

    DOE Patents [OSTI]

    Burelbach, J.P.; Kann, W.J.; Pan, Y.C.; Saiveau, J.G.; Seidensticker, R.W.

    1984-04-26T23:59:59.000Z

    For holding the reactor core in the confining reactor vessel, a support is disclosed that is structurally independent of the vessel, that is dimensionally accurate and stable, and that comprises tandem tension linkages that act redundantly of one another to maintain stabilized core support even in the unlikely event of the complete failure of one of the linkages. The core support has a mounting platform for the reactor core, and unitary structure including a flange overlying the top edge of the reactor vessels, and a skirt and box beams between the flange and platform for establishing one of the linkages. A plurality of tension rods connect between the deck closing the reactor vessel and the platform for establishing the redundant linkage. Loaded Belleville springs flexibly hold the tension rods at the deck and separable bayonet-type connections hold the tension rods at the platform.

  11. What could a million cores do to solve Integer Programs?

    E-Print Network [OSTI]

    Thorsten Koch,,,

    Jan 8, 2012 ... ensuring that the data required to perform each of these task is locally available to the core ... considered comparatively energy efficient. Since the ...... nical Report CentER Discussion Paper 2007-20, Tilburg University, The.

  12. Sterile neutrino oscillations in core-collapse supernova simulations

    E-Print Network [OSTI]

    Warren, MacKenzie L; Mathews, Grant; Hidaka, Jun; Kajino, Toshitaka

    2014-01-01T23:59:59.000Z

    We have made core-collapse supernova simulations that allow oscillations between electron neutrinos (or their anti particles) with right-handed sterile neutrinos. We have considered a range of mixing angles and sterile neutrino masses including those consistent with sterile neutrinos as a dark matter candidate. We examine whether such oscillations can impact the core bounce and shock reheating in supernovae. We identify the optimum ranges of mixing angles and masses that can dramatically enhance the supernova explosion by efficiently transporting electron anti-neutrinos from the core to behind the shock where they provide additional heating leading to much larger explosion kinetic energies. We show that an interesting oscillation in the neutrino luminosity develops due to a cycle of depletion of the neutrino density by conversion to sterile neutrinos that shuts off the conversion, followed by a replenished neutrino density as neutrinos transport through the core.

  13. A many-core software framework for embedded space computing

    E-Print Network [OSTI]

    Sun, Eugene Yu-Ting

    2013-01-01T23:59:59.000Z

    Space computing has long called for powerful yet power-efficient hardware for on-board computation. The emergence of many-core CPUs on a single die provides one potential solution. The development of processors like Maestro ...

  14. Evidence for a Weak Iron Core at Earth's Center

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

    Iron Core at Earth's Center Print Seismic waves that pass through the center of the Earth travel faster going from pole to pole than along the equatorial plane-why? One theory...

  15. Doubling Estimates of Light Elements in the Earth's Core | Advanced...

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

    relation of both hcp-Fe and the iron-silicon alloy at 300 K. The inner core of the Earth is the remotest area on the globe, mostly impossible to study directly. It is an area...

  16. Earth's Core Reveals an Inner Weakness | Advanced Photon Source

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

    their results to core conditions and found that the strength of iron deep within the Earth is lower than previously thought. This weakness may explain how the crystal structure...

  17. Porous Core-Shell Nanostructures for Catalytic Applications

    E-Print Network [OSTI]

    Ewers, Trevor David

    2012-01-01T23:59:59.000Z

    Titanium Incorporation within Silica Shell . 7.3 Pyridine5 Oxidative Growth of ZnO for Core-Shell Catalysis 5.13.3.2 Shell interaction dependent catalysis 3.3.3 Thermal

  18. Complex Modulus Prediction of Asphalt Concrete Pavement Cores 

    E-Print Network [OSTI]

    Ling, Meng

    2013-12-02T23:59:59.000Z

    . For field cores complex modulus measuring methods, except some expensive pavement field testers, empirical and semiempirical models are widely used, but an accurate mechanical test method is more desired. In this research, Arizona, Yellowstone National Park...

  19. Selected Data from Continental Scientific Drilling Core Holes...

    Open Energy Info (EERE)

    Selected Data from Continental Scientific Drilling Core Holes VC-1 and VC-2A, Valles Caldera, New Mexico Jump to: navigation, search OpenEI Reference LibraryAdd to library Report:...

  20. Scattering of infrared light by dielectric core-shell particles

    E-Print Network [OSTI]

    Thiessen, E; Heinisch, R L; Fehske, H

    2015-01-01T23:59:59.000Z

    We study the scattering of infrared light by small dielectric core-shell particles taking a sapphire sphere with a CaO core as an example. The extinction efficiency of such a particle shows two intense series of resonances attached, respectively, to in-phase and out-of-phase multipolar polarization-induced surface charges build-up, respectively, at the core-shell and the shell-vacuum interface. Both series, the character of the former may be labelled bonding and the character of the latter antibonding, give rise to anomalous scattering. For a given particle radius and filling factor the Poynting vector field shows therefore around two wave numbers the complex topology of this type of light scattering. Inside the particle the topology depends on the character of the resonance. The dissipation of energy inside the particle also reflects the core-shell structure. It depends on the resonance and shows strong spatial variations.

  1. A Critique of Core--Collapse Supernova Theory Circa 1997

    E-Print Network [OSTI]

    Adam Burrows

    1997-03-02T23:59:59.000Z

    There has been a new infusion of ideas in the study of the mechanism and early character of core--collapse supernovae. However, despite recent conceptual and computational progress, fundamental questions remain. Some are summarize herein.

  2. analysis identifies core: Topics by E-print Network

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

    not only from rotating core-collapse and bounce, the subsequent ring down of the proto-neutron star (PNS) as previously identified, but also from the formation of...

  3. The Faculty of Arts and Sciences High Performance Computing Core

    E-Print Network [OSTI]

    O'Hern, Corey S.

    The Faculty of Arts and Sciences High Performance Computing Core Advanced Computational Support/09/2010-9FAS HPC Center #12;Understanding Data Requirements 04/09/2010-10FAS HPC Center Source: Adriana Corona

  4. Core/corona modeling of diode-imploded annular loads

    SciTech Connect (OSTI)

    Terry, R.E.; Guillory, J.U.

    1980-11-07T23:59:59.000Z

    The effects of a tenuous exterior plasma corona with anomalous resistivity on the compression and heating of a hollow, collisional aluminum z-pinch plasma are predicted by a one-dimensional code. As the interior ('core') plasma is imploded by its axial current, the energy exchange between core and corona determines the current partition. Under the conditions of rapid core heating and compression, the increase in coronal current provides a trade-off between radial acceleration and compression, which reduces the implosion forces and softens the pitch. Combined with a heuristic account of energy and momentum transport in the strongly coupled core plasma and an approximate radiative loss calculation including Al line, recombination and Bremsstrahlung emission, the current model can provide a reasonably accurate description of imploding annular plasma loads that remain azimuthally symmetric. The implications for optimization of generator load coupling are examined.

  5. Core Holes At Valles Caldera - Sulphur Springs Geothermal Area...

    Open Energy Info (EERE)

    Dennis L. Nielson, Pisto Larry, C.W. Criswell, R. Gribble, K. Meeker, J.A. Musgrave, T. Smith, D. Wilson (1989) Scientific Core Hole Valles Caldera No. 2B (VC-2B), New Mexico:...

  6. Earth's Inner Core dynamics induced by the Lorentz force

    E-Print Network [OSTI]

    Lasbleis, M; Cardin, P; Labrosse, S

    2015-01-01T23:59:59.000Z

    Seismic studies indicate that the Earth's inner core has a complex structure and exhibits a strong elastic anisotropy with a cylindrical symmetry. Among the various models which have been proposed to explain this anisotropy, one class of models considers the effect of the Lorentz force associated with the magnetic field diffused within the inner core. In this paper we extend previous studies and use analytical calculations and numerical simulations to predict the geometry and strength of the flow induced by the poloidal component of the Lorentz force in a neutrally or stably stratified growing inner core, exploring also the effect of different types of boundary conditions at the inner core boundary (ICB). Unlike previous studies, we show that the boundary condition that is most likely to produce a significant deformation and seismic anisotropy is impermeable, with negligible radial flow through the boundary. Exact analytical solutions are found in the case of a negligible effect of buoyancy forces in the inne...

  7. High-voltage air-core pulse transformers

    SciTech Connect (OSTI)

    Rohwein, G. J.

    1981-01-01T23:59:59.000Z

    General types of air core pulse transformers designed for high voltage pulse generation and energy transfer applications are discussed with special emphasis on pulse charging systems which operate up to the multi-megavolt range. The design, operation, dielectric materials, and performance are described. It is concluded that high voltage air core pulse transformers are best suited to applications outside the normal ranges of conventional magnetic core transformers. In general these include charge transfer at high power levels and fast pulse generation with comparatively low energy. When properly designed and constructed, they are capable of delivering high energy transfer efficiency and have demonstrated superior high voltage endurance. The principal disadvantage of high voltage air core transformers is that they are not generally available from commercial sources. Consequently, the potential user must become thoroughly familiar with all aspects of design, fabrication and system application before he can produce a high performance transformer system. (LCL)

  8. Webinar: Review Core Competencies for Appraisers to Value Green Buildings

    Broader source: Energy.gov [DOE]

    The Appraisal Foundation is developing a document to describe the fundamentals of the Valuation of Green Buildings. This document highlights the core skill sets and data necessary for appraisers to...

  9. Structural Flexibility of the Nucleosome Core Particle at Atomic...

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

    have been performed on a complete nucleosome core particle with and without N-terminal histone tails for more than 20 ns. Main purpose of the simulations was to study the...

  10. A Plastic-Core Compact Heat Exchanger for Energy Conservation

    E-Print Network [OSTI]

    Lazaridis, A.; Rafailidis, E.

    This paper describes a compact, single-pass, cross-flow type, gas-to-gas heat exchanger with a polyolefin (polyethylene or polypropylene) core whose seams are welded through a proprietary process. It is constructed of several extruded polyolefin...

  11. The End of Core: Should Disruptive Innovation in Telecommunication

    E-Print Network [OSTI]

    de Weck, Olivier L.

    The End of Core: Should Disruptive Innovation in Telecommunication Invoke Discontinuous Regulation, USA Master of Science, Technology and Policy Program Massachusetts Institute of Technology, USA of Doctor of Philosophy in Technology, Management, and Policy at the Massachusetts Institute of Technology

  12. Solid0Core Heat-Pipe Nuclear Batterly Type Reactor

    SciTech Connect (OSTI)

    Ehud Greenspan

    2008-09-30T23:59:59.000Z

    This project was devoted to a preliminary assessment of the feasibility of designing an Encapsulated Nuclear Heat Source (ENHS) reactor to have a solid core from which heat is removed by liquid-metal heat pipes (HP).

  13. A Plastic-Core Compact Heat Exchanger for Energy Conservation 

    E-Print Network [OSTI]

    Lazaridis, A.; Rafailidis, E.

    1995-01-01T23:59:59.000Z

    This paper describes a compact, single-pass, cross-flow type, gas-to-gas heat exchanger with a polyolefin (polyethylene or polypropylene) core whose seams are welded through a proprietary process. It is constructed of several extruded polyolefin...

  14. Superconducting shielded core reactor with reduced AC losses

    DOE Patents [OSTI]

    Cha, Yung S.; Hull, John R.

    2006-04-04T23:59:59.000Z

    A superconducting shielded core reactor (SSCR) operates as a passive device for limiting excessive AC current in a circuit operating at a high power level under a fault condition such as shorting. The SSCR includes a ferromagnetic core which may be either closed or open (with an air gap) and extends into and through a superconducting tube or superconducting rings arranged in a stacked array. First and second series connected copper coils each disposed about a portion of the iron core are connected to the circuit to be protected and are respectively wound inside and outside of the superconducting tube or rings. A large impedance is inserted into the circuit by the core when the shielding capability of the superconducting arrangement is exceeded by the applied magnetic field generated by the two coils under a fault condition to limit the AC current in the circuit. The proposed SSCR also affords reduced AC loss compared to conventional SSCRs under continuous normal operation.

  15. annular core pulse: Topics by E-print Network

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

    A good un- derstanding- tions. For example, the use of core-annular flows facilitates water-lubricated transport of heavy viscous oils by providing new approaches to mitigate...

  16. A Critique of Core-Collapse Supernova Theory Circa 1997

    E-Print Network [OSTI]

    Burrows, A

    1998-01-01T23:59:59.000Z

    There has been a new infusion of ideas in the study of the mechanism and early character of core--collapse supernovae. However, despite recent conceptual and computational progress, fundamental questions remain. Some are summarize herein.

  17. Technische Universitt Mnchen Potentials and Challenges for Multi-Core

    E-Print Network [OSTI]

    Berns, Karsten

    · Object recognition · Motor control · Current Sensing Motor Motor Motor Processing Units and Workload-Core in Robotic Applications Folie 2 Technische Universität München Embedded Systems Trends Embedded Systems control · Torque control · Movement coordination Task Coordination · Platform control · Localization

  18. Summary of multi-core hardware and programming model investigations

    SciTech Connect (OSTI)

    Kelly, Suzanne Marie; Pedretti, Kevin Thomas Tauke; Levenhagen, Michael J.

    2008-05-01T23:59:59.000Z

    This report summarizes our investigations into multi-core processors and programming models for parallel scientific applications. The motivation for this study was to better understand the landscape of multi-core hardware, future trends, and the implications on system software for capability supercomputers. The results of this study are being used as input into the design of a new open-source light-weight kernel operating system being targeted at future capability supercomputers made up of multi-core processors. A goal of this effort is to create an agile system that is able to adapt to and efficiently support whatever multi-core hardware and programming models gain acceptance by the community.

  19. SBIR Final Report. Liquid Core Optical Scintillating Fibers

    SciTech Connect (OSTI)

    Beetz, C.P.; Steinbeck, J.; Buerstler, R.

    2000-05-16T23:59:59.000Z

    This Phase I SBIR project focused on developing flexible scintillating liquid core optical fibers, with potential uses in high-energy calorimetry, tracking, preradiators, active targets or other fast detectors. Progress on the six tasks of the project is summarized. The technical developments involve three technology components: (1) highly flexible capillaries or tubes of relatively low n (index of refraction) to serve as cladding and liquid core containment; (2) scintillator (and clear) fluids of relatively high n to serve as a core-- these fluids must have a high light transmission and, for some applications, radiation hardness; (3) optical end plugs, plug insertion, and plug-cladding tube sealing technology to contain the core fluids in the tubes, and to transmit the light.

  20. Neutronic evaluation of GCFR core diluents and reflectors

    E-Print Network [OSTI]

    Yu, Kun, 1974-

    2003-01-01T23:59:59.000Z

    Materials are evaluated for use as in-core diluents and as peripheral reflectors for Gas-Cooled Fast Reactor (GFR) service, using coupled Monte Carlo (MCNP) and isotopics (ORIGEN) codes. The principal performance indices ...

  1. advanced core design: Topics by E-print Network

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

    SiCfSiC at a substantially lower temperature California at San Diego, University of 2 Fusion Engineering and Design 82 (2007) 217236 Advanced power core system for the Plasma...

  2. Laboratory methods for enhanced oil recovery core floods

    SciTech Connect (OSTI)

    Robertson, E.P.; Bala, G.A.; Thomas, C.P.

    1994-03-01T23:59:59.000Z

    Current research at the Idaho National Engineering Laboratory (INEL) is investigating microbially enhanced oil recovery (MEOR) systems for application to oil reservoirs. Laboratory corefloods are invaluable in developing technology necessary for a field application of MEOR. Methods used to prepare sandstone cores for experimentation, coreflooding techniques, and quantification of coreflood effluent are discussed in detail. A technique to quantify the small volumes of oil associated with laboratory core floods is described.

  3. Gravitating Fermionic Lumps with a False Vacuum Core

    E-Print Network [OSTI]

    Ramin G. Daghigh; Yutaka Hosotani

    2004-02-03T23:59:59.000Z

    We investigate gravitating lumps with a false vacuum core surrounded by the true vacuum in a scalar field potential. Such configurations become possible in the Einstein gravity in the presence of fermions at the core. Gravitational interactions as well as Yukawa interactions are essential for such lumps to exist. The mass and size of gravitating lumps sensitively depend on the scale characterizing the scalar field potential and the density of fermions. These objects can exist in the universe at various scales.

  4. Oxide Shell Reduction and Magnetic Property Changes in Core-Shell...

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

    Shell Reduction and Magnetic Property Changes in Core-Shell Fe Nanoclusters under Ion Irradiation. Oxide Shell Reduction and Magnetic Property Changes in Core-Shell Fe Nanoclusters...

  5. Core/Shell heterojunction nanowire solar cell fabricated by lithographically patterned nanowire electrodeposition method

    E-Print Network [OSTI]

    Ghosh, Somnath

    2012-01-01T23:59:59.000Z

    Menke. Gold Core–Semiconductor Shell Nanowires Prepared bycarrier concentration in CIS shell at different depositionMerced Dissertation: Core/Shell Heterojunction Nanowires

  6. Comparative genomics of the core and accessory genomes of 48 Sinorhizobium strains comprising five genospecies

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    annotation and comparative genomics. Database (Oxford) 2009,et al. : Comparative genomics of the core and accessoryComparative genomics of the core and accessory genomes of 48

  7. Efficiency of static core turn-off in a system-on-a-chip with variation

    DOE Patents [OSTI]

    Cher, Chen-Yong; Coteus, Paul W; Gara, Alan; Kursun, Eren; Paulsen, David P; Schuelke, Brian A; Sheets, II, John E; Tian, Shurong

    2013-10-29T23:59:59.000Z

    A processor-implemented method for improving efficiency of a static core turn-off in a multi-core processor with variation, the method comprising: conducting via a simulation a turn-off analysis of the multi-core processor at the multi-core processor's design stage, wherein the turn-off analysis of the multi-core processor at the multi-core processor's design stage includes a first output corresponding to a first multi-core processor core to turn off; conducting a turn-off analysis of the multi-core processor at the multi-core processor's testing stage, wherein the turn-off analysis of the multi-core processor at the multi-core processor's testing stage includes a second output corresponding to a second multi-core processor core to turn off; comparing the first output and the second output to determine if the first output is referring to the same core to turn off as the second output; outputting a third output corresponding to the first multi-core processor core if the first output and the second output are both referring to the same core to turn off.

  8. ESPP Functional Genomics and Imaging Core: Cell wide analysis of Metal-Reducing Bacteria

    E-Print Network [OSTI]

    Mukhopadhyay, Aindrila

    2014-01-01T23:59:59.000Z

    and Environmental Research, Genomics:GTL Program throughESPP Functional Genomics and Imaging Core: Cell widemetals. The Functional Genomics and Imaging Core (FGIC)

  9. home of the Get Home Delivery | Today's Paper

    E-Print Network [OSTI]

    Weiss, Benjamin P.

    : 1 engine missing from jet in Hudson 01.16.09 Israel to vote Saturday on Gaza truce 01.16.09 Obama, with a liquid iron core that spun like a dynamo to produce a magnetic field much like Earth's but very much magnetism bound inside its modern rocks. It also fits in with many current theories that around 4.5 billion

  10. HAZING POLICY Clemson University's core values are Integrity, Honesty and Respect. Hazing is not consistent with these core

    E-Print Network [OSTI]

    Stuart, Steven J.

    HAZING POLICY Clemson University's core values are Integrity, Honesty and Respect. Hazing; or · Potentially harmful to o Physical safety/health o Psychological well-being o Opportunities for Academic

  11. Giant planet formation: episodic impacts vs. gradual core growth

    E-Print Network [OSTI]

    Broeg, Christopher

    2011-01-01T23:59:59.000Z

    We describe the growth of gas giant planets in the core accretion scenario. The core growth is not modeled as a gradual accretion of planetesimals but as episodic impacts of large mass ratios, i.e. we study impacts of 0.02 - 1 Earth masses onto cores of 1-15 Earth masses. Such impacts could deliver the majority of solid matter in the giant impact regime. We focus on the thermal response of the envelope to the energy delivery. Previous studies have shown that sudden shut off of core accretion can dramatically speed up gas accretion. We therefore expect that giant impacts followed by periods of very low core accretion will result in a net increase in gas accretion rate. This study aims at modelling such a sequence of events and to understand the reaction of the envelope to giant impacts in more detail. To model this scenario, we spread the impact energy deposition over a time that is long compared to the sound crossing time, but very short compared to the Kelvin-Helmholtz time. The simulations are done in spher...

  12. An expert system for PWR core operation management

    SciTech Connect (OSTI)

    Ida, Toshio; Masuda, Masahiro; Nishioka, Hiromasa

    1988-01-01T23:59:59.000Z

    Planning for restartup after planned or unplanned reactor shutdown and load-follow operations is an important task in the core operation management of pressurized water reactors (PWRs). These planning problems have been solved by planning experts using their expertise and the computational prediction of core behavior. Therefore, the quality of the plan and the time consumed in the planning depend heavily on the skillfulness of the planning experts. A knowledge engineering approach has been recently considered as a promising means to solve such complicated planning problems. Many knowledge-based systems have been developed so far, and some of them have already been applied because of their effectiveness. The expert system REPLEX has been developed to aid core management engineers in making a successful plan for the restartup or the load-follow operation of PWRs within a shorter time. It can maintain planning tasks at a high-quality level independent of the skillfulness of core management engineers and enhance the efficiency of management. REPLEX has an explanation function that helps user understanding of plans. It could be a useful took, therefore, for the training of core management engineers.

  13. The Role of a Dipeptide Outer-Coordination Sphere on H2 -Production Catalysts: Influence on Catalytic Rates and Electron Transfer

    SciTech Connect (OSTI)

    Reback, Matthew L.; Ginovska-Pangovska, Bojana; Ho, Ming-Hsun; Jain, Avijita; Squier, Thomas C.; Raugei, Simone; Roberts, John A.; Shaw, Wendy J.

    2013-02-04T23:59:59.000Z

    The outer-coordination sphere of enzymes acts to fine-tune the active site reactivity and control catalytic rates, suggesting that incorporation of analogous structural elements into molecular catalysts may be necessary to achieve rates comparable to those observed in enzyme systems at low overpotentials. In this work, we evaluate the effect of an amino acid and dipeptide outer-coordination sphere on [Ni(PPh2NPh-R2)2]2+ hydrogen production catalysts. A series of 12 new complexes containing non-natural amino acids or dipeptides were prepared to test the effects of positioning, size, polarity and aromaticity on catalytic activity. The non-natural amino acid was either 3-(meta- or para-aminophenyl)propionic acid terminated as an acid, an ester or an amide. Dipeptides consisted of one of the non-natural amino acids coupled to one of four amino acid esters: alanine, serine, phenylalanine or tyrosine. All of the catalysts are active for hydrogen production, with rates averaging ~1000 s-1, 40% faster than the unmodified catalyst. Structure and polarity of the aliphatic or aromatic side chains of the C-terminal peptide do not strongly influence rates. However, the presence of an amide bond increases rates, suggesting a role for the amide in assisting catalysis. Overpotentials were lower with substituents at the N-phenyl meta position. This is consistent with slower electron transfer in the less compact, para-substituted complexes, as shown in digital simulations of catalyst cyclic voltammograms and computational modeling of the complexes. Combining the current results with insights from previous results, we propose a mechanism for the role of the amino acid and dipeptide based outer-coordination sphere in molecular hydrogen production catalysts.

  14. Core Microturbulence and Edge MHD Interplay and Stabilization by Fast Ions in Tokamak Confined Plasmas

    E-Print Network [OSTI]

    Core Microturbulence and Edge MHD Interplay and Stabilization by Fast Ions in Tokamak Confined Plasmas

  15. Safety and core design of large liquid-metal cooled fast breeder reactors

    E-Print Network [OSTI]

    Qvist, Staffan Alexander

    2013-01-01T23:59:59.000Z

    breeder reactors typically operate with an inner core of high fissile content surrounded by breeding blankets

  16. Energy-Aware Scheduling for Aperiodic Tasks on Multi-core Processors

    E-Print Network [OSTI]

    Wu, Jie

    consumed by processors or processing cores. To facilitate energy-efficient design, the Dynamic Voltage

  17. Containment, Equivalence and Coreness from CSP to QCSP and beyond

    E-Print Network [OSTI]

    Madelaine, Florent

    2012-01-01T23:59:59.000Z

    The constraint satisfaction problem (CSP) and its quantified extensions, whether without (QCSP) or with disjunction (QCSP_or), correspond naturally to the model checking problem for three increasingly stronger fragments of positive first-order logic. Their complexity is often studied when parameterised by a fixed model, the so-called template. It is a natural question to ask when two templates are equivalent, or more generally when one "contain" another, in the sense that a satisfied instance of the first will be necessarily satisfied in the second. One can also ask for a smallest possible equivalent template: this is known as the core for CSP. We recall and extend previous results on containment, equivalence and "coreness" for QCSP_or before initiating a preliminary study of cores for QCSP which we characterise for certain structures and which turns out to be more elusive.

  18. Assessment of HCDA energetics in the CRBRP heterogeneous reactor core

    SciTech Connect (OSTI)

    Rhow, S K; Switick, D M; McElroy, J L; Joe, B W; Elawar, Z J

    1981-03-27T23:59:59.000Z

    The results of hypothetical core disruptive event analyses for the CRBRP heterogeneous reactor core are reported. The analytical results cover a large number of parametric cases including variations in design parameters and phenomenological assumptions. Reactor core configurations at the beginning of cycle one and end of cycle four are evaluated. The energetic consequences are evaluated based upon both fuel expansion thermodynamic work potential and a relative probability assignment. It is concluded that the structural loads, which result from 101 megajoules of available expansion work at sodium slug impact on the reactor closure head (equivalent to 661 megajoules of fuel expansion work to one atmosphere), is an adequate energetic consequence envelope for use in specifying the Structural Margins Beyond the Design Basis.

  19. Heatup of the TMI-2 lower head during core relocation

    SciTech Connect (OSTI)

    Wang, S.K.; Sienicki, J.J.; Spencer, B.W.

    1989-01-01T23:59:59.000Z

    An analysis has been carried out to assess the potential of a melting attack upon the reactor vessel lower head and incore instrument nozzle penetration weldments during the TMI core relocation event at 224 minutes. Calculations were performed to determine the potential for molten corium to undergo breakup into droplets which freeze and form a debris bed versus impinging upon the lower head as one or more coherent streams. The effects of thermal-hydraulic interactions between corium streams and water inside the lower plenum, the effects of the core support assembly structure upon the corium, and the consequences of corium relocation by way of the core former region were examined. 19 refs., 24 figs.

  20. MHD Simulations of Core Collapse Supernovae with Cosmos++

    E-Print Network [OSTI]

    Akiyama, Shizuka

    2010-01-01T23:59:59.000Z

    We performed 2D, axisymmetric, MHD simulations with Cosmos++ in order to examine the growth of the magnetorotational instability (MRI) in core--collapse supernovae. We have initialized a non--rotating 15 solar mass progenitor, infused with differential rotation and poloidal magnetic fields. The collapse of the iron core is simulated with the Shen EOS, and the parametric Ye and entropy evolution. The wavelength of the unstable mode in the post--collapse environment is expected to be only ~ 200 m. In order to achieve the fine spatial resolution requirement, we employed remapping technique after the iron core has collapsed and bounced. The MRI unstable region appears near the equator and angular momentum and entropy are transported outward. Higher resolution remap run display more vigorous overturns and stronger transport of angular momentum and entropy. Our results are in agreement with the earlier work by Akiyama et al. (2003) and Obergaulinger et al. (2009).

  1. Apparatus For Laminating Segmented Core For Electric Machine

    DOE Patents [OSTI]

    Lawrence, Robert Anthony (Kokomo, IN); Stabel, Gerald R (Swartz Creek, MI)

    2003-06-17T23:59:59.000Z

    A segmented core for an electric machine includes segments stamped from coated electric steel. The segments each have a first end, a second end, and winding openings. A predetermined number of segments are placed end-to-end to form layers. The layers are stacked such that each of the layers is staggered from adjacent layers by a predetermined rotation angle. The winding openings of each of the layers are in vertical alignment with the winding openings of the adjacent layers. The stack of layers is secured to form the segmented core.

  2. Prediction of core saturation instability at an HVDC converter

    SciTech Connect (OSTI)

    Burton, R.S. [Teshmont Consultants, Inc., Winnipeg, Manitoba (Canada)] [Teshmont Consultants, Inc., Winnipeg, Manitoba (Canada); Fuchshuber, C.F. [Alberta Power Ltd., Edmonton, Alberta (Canada)] [Alberta Power Ltd., Edmonton, Alberta (Canada); Woodford, D.A. [Manitoba HVDC Research Centre, Winnipeg, Manitoba (Canada)] [Manitoba HVDC Research Centre, Winnipeg, Manitoba (Canada); Gole, A.M. [Univ. of Manitoba, Winnipeg, Manitoba (Canada)] [Univ. of Manitoba, Winnipeg, Manitoba (Canada)

    1996-10-01T23:59:59.000Z

    Core saturation instability has occurred on several HVDC schemes resulting from interactions between second harmonic and dc quantities (voltages and currents) on the ac side of the converter and fundamental frequency quantities on the dc side of the converter. The instability can be reinforced by unbalanced saturation of the converter transformers. The paper presents an analytical method which can be used to quickly screen ac and dc system operating conditions to predict where core saturation instability is likely to occur. Analytical results have been confirmed using the digital transients simulation program PSCAD/EMTDC.

  3. Acknowledging the Input of Core Facilities A common question of labs when working with core facilities is how best to acknowledge or include as authors the

    E-Print Network [OSTI]

    Richardson, David

    Acknowledging the Input of Core Facilities A common question of labs when working with core facilities is how best to acknowledge or include as authors the Core in the publication of results, the decision of inclusion on manuscripts or acknowledgement is up to the senior author (or PI

  4. Investigating the Effects of Core Length on Pore Volume to Breakthrough (PVBT) Behavior in Carbonate Core Samples during Matrix Acidizing with Hydrochloric Acid 

    E-Print Network [OSTI]

    Nour, Mohamed

    2014-05-06T23:59:59.000Z

    an increased PVBT for 20 inch cores compared to the 6 inch samples. Results from CAT scan experiments show enlarged worm-holing and face dissolution on the 20 inch cores compared to the 6 inch cores, due to increased acid spending at the same acid concentration...

  5. Multi-core and Many-core Shared-memory Parallel Raycasting Volume Rendering Optimization and Tuning

    SciTech Connect (OSTI)

    Howison, Mark

    2012-01-31T23:59:59.000Z

    Given the computing industry trend of increasing processing capacity by adding more cores to a chip, the focus of this work is tuning the performance of a staple visualization algorithm, raycasting volume rendering, for shared-memory parallelism on multi-core CPUs and many-core GPUs. Our approach is to vary tunable algorithmic settings, along with known algorithmic optimizations and two different memory layouts, and measure performance in terms of absolute runtime and L2 memory cache misses. Our results indicate there is a wide variation in runtime performance on all platforms, as much as 254% for the tunable parameters we test on multi-core CPUs and 265% on many-core GPUs, and the optimal configurations vary across platforms, often in a non-obvious way. For example, our results indicate the optimal configurations on the GPU occur at a crossover point between those that maintain good cache utilization and those that saturate computational throughput. This result is likely to be extremely difficult to predict with an empirical performance model for this particular algorithm because it has an unstructured memory access pattern that varies locally for individual rays and globally for the selected viewpoint. Our results also show that optimal parameters on modern architectures are markedly different from those in previous studies run on older architectures. And, given the dramatic performance variation across platforms for both optimal algorithm settings and performance results, there is a clear benefit for production visualization and analysis codes to adopt a strategy for performance optimization through auto-tuning. These benefits will likely become more pronounced in the future as the number of cores per chip and the cost of moving data through the memory hierarchy both increase.

  6. Core Design and Scalability of Tiled SDF Architecture

    E-Print Network [OSTI]

    Giorgi, Roberto

    Core Design and Scalability of Tiled SDF Architecture Roberto Giorgi, Zdravko Popovic Dept be applied on the SDF architecture. KEYWORDS: multiprocessor architectures, scalability, wire delay, chip is based on the SDF architecture [9] [10]. SDF exploits a simple paradigm that is based on dataflow

  7. Serially connected solid oxide fuel cells having monolithic cores

    DOE Patents [OSTI]

    Herceg, J.E.

    1985-05-20T23:59:59.000Z

    Disclosed is a solid oxide fuel cell for electrochemically combining fuel and oxidant for generating galvanic output. The cell core has an array of cell segments electrically serially connected in the flow direction, each segment consisting of electrolyte walls and interconnect that are substantially devoid of any composite inert materials for support. Instead, the core is monolithic, where each electrolyte wall consists of thin layers of cathode and anode materials sandwiching a thin layer of electrolyte material therebetween. Means direct the fuel to the anode-exposed core passageways and means direct the oxidant to the cathode-exposed core passageways; and means also direct the galvanic output to an exterior circuit. Each layer of the electrolyte composite materials is of the order of 0.002 to 0.01 cm thick; and each layer of the cathode and anode materials is of the order of 0.002 to 0.05 cm thick. Between 2 and 50 cell segments may be connected in series.

  8. Generation of Core/shell Nanoparticles with Laser Ablation 

    E-Print Network [OSTI]

    Jo, Young Kyong

    2012-10-19T23:59:59.000Z

    Two types of core/shell nanoparticles (CS-NPs) generation based on laser ablation are developed in this study, namely, double pulse laser ablation and laser ablation in colloidal solutions. In addition to the study of the generation mechanism of CS...

  9. Soft-core processor study for node-based architectures.

    SciTech Connect (OSTI)

    Van Houten, Jonathan Roger; Jarosz, Jason P.; Welch, Benjamin James; Gallegos, Daniel E.; Learn, Mark Walter

    2008-09-01T23:59:59.000Z

    Node-based architecture (NBA) designs for future satellite projects hold the promise of decreasing system development time and costs, size, weight, and power and positioning the laboratory to address other emerging mission opportunities quickly. Reconfigurable Field Programmable Gate Array (FPGA) based modules will comprise the core of several of the NBA nodes. Microprocessing capabilities will be necessary with varying degrees of mission-specific performance requirements on these nodes. To enable the flexibility of these reconfigurable nodes, it is advantageous to incorporate the microprocessor into the FPGA itself, either as a hardcore processor built into the FPGA or as a soft-core processor built out of FPGA elements. This document describes the evaluation of three reconfigurable FPGA based processors for use in future NBA systems--two soft cores (MicroBlaze and non-fault-tolerant LEON) and one hard core (PowerPC 405). Two standard performance benchmark applications were developed for each processor. The first, Dhrystone, is a fixed-point operation metric. The second, Whetstone, is a floating-point operation metric. Several trials were run at varying code locations, loop counts, processor speeds, and cache configurations. FPGA resource utilization was recorded for each configuration. Cache configurations impacted the results greatly; for optimal processor efficiency it is necessary to enable caches on the processors. Processor caches carry a penalty; cache error mitigation is necessary when operating in a radiation environment.

  10. Mapping the core mass function to the initial mass function

    E-Print Network [OSTI]

    Guszejnov, David

    2014-01-01T23:59:59.000Z

    It has been shown that fragmentation within self-gravitating, turbulent molecular clouds ("turbulent fragmentation") can naturally explain the observed properties of protostellar cores, including the core mass function (CMF). Here, we extend recently-developed analytic models for turbulent fragmentation to follow the time-dependent hierarchical fragmentation of self-gravitating cores, until they reach effectively infinite density (and form stars). We show that turbulent fragmentation robustly predicts two key features of the IMF. First, a high-mass power-law scaling very close to the Salpeter slope, which is a generic consequence of the scale-free nature of turbulence and self-gravity. We predict the IMF slope (-2.3) is slightly steeper then the CMF slope (-2.1), owing to the slower collapse and easier fragmentation of large cores. Second, a turnover mass, which is set by a combination of the CMF turnover mass (a couple solar masses, determined by the `sonic scale' of galactic turbulence, and so weakly depend...

  11. COLLEGE OF MEDIA CORE (12 hrs) Media & Society

    E-Print Network [OSTI]

    Mohaghegh, Shahab

    hrs) Visual Journalism/ New Media JRL 225 (3 hrs) Media Ethics & Law JRL 428 (3 hrs) STRATEGICCOLLEGE OF MEDIA CORE (12 hrs) Intro to Media & Society JRL 101 (3 hrs) Media Writing JRL 215 (3: Creative I ADV 401 (3 hrs) Media Planning & Strategy ADV 403 (3 hrs) Interactive Marketing Communications

  12. Page 1 of 7 Catamount Software Architecture with Dual Core

    E-Print Network [OSTI]

    Brightwell, Ron

    , Dual Core. 1.0 Background A massively parallel processor (MPP), high performance computing (HPC) system of Energy's National Nuclear Security Administration under contract DE-AC04- 94AL85000. synchronization on node specialization [3]. Sets of nodes in an MPP are designated to perform specific tasks, each running

  13. FACETS: Framework Application for Core-Edge Transport Simulations

    E-Print Network [OSTI]

    -institutional main project: Tech-X (Physics, CS/AM); LLNL (Physics, CS/AM); PPPL (Physics); ANL (CS/AM); UCSD (Physics); CSU (AM); ORNL (CS, perf); ParaTools (CS, perf) · Appended SAP: GA, ORNL · Advisory: Columbia transitions · Core is a collisionless, 1D transport system with local, only-cross-surface fluxes · Edge

  14. Small core axial compressors for high efficiency jet aircraft

    E-Print Network [OSTI]

    DiOrio, Austin Graf

    2012-01-01T23:59:59.000Z

    This thesis quantifies mechanisms that limit efficiency in small core axial compressors, defined here as compressor exit corrected flow between 1.5 and 3.0 lbm/s. The first part of the thesis describes why a small engine ...

  15. Predictors of Threat and Error Management: Identification of Core

    E-Print Network [OSTI]

    Predictors of Threat and Error Management: Identification of Core Nontechnical Skills In normal flight operations, crews are faced with a variety of external threats and commit a range of errors of these threats and errors therefore forms an essential element of enhancing performance and minimizing risk

  16. Generation of Core/shell Nanoparticles with Laser Ablation

    E-Print Network [OSTI]

    Jo, Young Kyong

    2012-10-19T23:59:59.000Z

    Two types of core/shell nanoparticles (CS-NPs) generation based on laser ablation are developed in this study, namely, double pulse laser ablation and laser ablation in colloidal solutions. In addition to the study of the generation mechanism of CS...

  17. High-index-core Bragg fibers: dispersion Juan A. Monsoriu

    E-Print Network [OSTI]

    Fernández de Córdoba, Pedro

    . P. Yeh, A. Yariv, and E. Marom, "Theory of Bragg fiber," J. Opt. Soc. Am. 68, 1196-1201 (1978). 4. Y. Xu, G.X. Ouyang, R.K. Lee, and A. Yariv, "Asymptotic Matrix Theory of Bragg Fibers," J. LightwaveHigh-index-core Bragg fibers: dispersion properties Juan A. Monsoriu Departamento de Física

  18. A Document Model Management Framework based on Core Components

    E-Print Network [OSTI]

    A Document Model Management Framework based on Core Components Michael Strommer, Christian Pichler for a consistent framework for the management of electronic business documents, together with tool support rises. Tools, that foster the management of document models in a way to overcome interoperability issues

  19. Next Generation Sequencing at the University of Chicago Genomics Core

    SciTech Connect (OSTI)

    Faber, Pieter [University of Chicago

    2013-04-24T23:59:59.000Z

    The University of Chicago Genomics Core provides University of Chicago investigators (and external clients) access to State-of-the-Art genomics capabilities: next generation sequencing, Sanger sequencing / genotyping and micro-arrays (gene expression, genotyping, and methylation). The current presentation will highlight our capabilities in the area of ultra-high throughput sequencing analysis.

  20. Measurement of Electromagnetic Parameters and FDTD Modeling of Ferrite Cores

    E-Print Network [OSTI]

    Koledintseva, Marina Y.

    Measurement of Electromagnetic Parameters and FDTD Modeling of Ferrite Cores Jianfeng Xu #1 products based on magneto-dielectric (ferrite) materials with desirable frequency responses that satisfy simulation tool that could deal with frequency- dispersive materials. An example of a ferrite material

  1. Continuously Optimized Reliable Energy (CORE) Microgrid: Models & Tools (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-07-01T23:59:59.000Z

    This brochure describes Continuously Optimized Reliable Energy (CORE), a trademarked process NREL employs to produce conceptual microgrid designs. This systems-based process enables designs to be optimized for economic value, energy surety, and sustainability. Capabilities NREL offers in support of microgrid design are explained.

  2. I. Required core Chemistry Courses (1905 & 1925) Chemistry

    E-Print Network [OSTI]

    Advisor: Advisee: I. Required core Chemistry Courses (1905 & 1925) Chemistry CH 111 PY 211 _____ PY 212 _____ (or PY 242 _____ or PY 252 ______) II. Chemistry Options (one required) 1905 (Concentration in Chemistry) Option A (2 advanced CH courses, 401 or higher, only one may

  3. Energy-Efficient Computing with Heterogeneous Multi-Cores

    E-Print Network [OSTI]

    Mitra, Tulika

    Energy-Efficient Computing with Heterogeneous Multi-Cores Tulika Mitra School of Computing National the application can be exploited leading to faster and energy-efficient computing. This paper describes of such architectures for improved energy-efficiency. I. INTRODUCTION The past decade has witnessed an unprecedented

  4. Core design studies for advanced burner test reactor.

    SciTech Connect (OSTI)

    Yang, W. S.; Kim, T. K.; Hill, R. N.; Nuclear Engineering Division

    2008-01-01T23:59:59.000Z

    The U.S. government announced in February 2006 the Global Nuclear Energy Partnership (GNEP) to expand the use of nuclear energy to meet increasing global energy demand, to address nuclear waste management concerns and to promote non-proliferation. The advanced burner reactor (ABR) based on a fast spectrum is one of the three major technologies to be demonstrated in GNEP. In FY06, a pre-conceptual design study was performed to develop an advanced burner test reactor (ABTR) that supports development of a prototype full-scale ABR, which would be followed by commercial deployment of ABRs. The primary objectives of the ABTR were (1) to demonstrate reactor-based transmutation of transuranics (TRU) as part of an advanced fuel cycle, (2) to qualify the TRU-containing fuels and advanced structural materials needed for a full-scale ABR, (3) to support the research, development and demonstration required for certification of an ABR standard design by the U.S. Nuclear Regulatory Commission. Based on these objectives, core design and fuel cycle studies were performed to develop ABTR core designs, which can accommodate the expected changes of the TRU feed and the conversion ratio. Various option and trade-off studies were performed to determine the appropriate power level and conversion ratio. Both ternary metal alloy (U-TRU-10Zr) and mixed oxide (UO{sub 2}-TRUO{sub 2}) fuel forms have been considered with TRU feeds from weapons-grade plutonium (WG-Pu) and TRU recovered from light water reactor spent fuel (LWR-SF). Reactor performances were evaluated in detail including equilibrium cycle core parameters, mass flow, power distribution, kinetic parameters, reactivity feedback coefficient, reactivity control requirements and shutdown margins, and spent fuel characteristics. Trade-off studies on power level suggested that about 250 MWt is a reasonable compromise to allow a low project cost, at the same time providing a reasonable prototypic irradiation environment for demonstrating TRU-based fuels. Preliminary design studies showed that it is feasible to design the ABTR to accommodate a wide range of conversion ratio (CR) by employing different assembly designs. The TRU enrichments required for various conversion ratios and the irradiation database suggested a phased approach with initial startup using conventional enrichment plutonium-based fuel and gradual transitioning to full core loading of transmutation fuel after its qualification phase (resulting in {approx}0.6 CR). The low CR transmutation fuel tests can be accommodated in the designated test assemblies, and if fully developed, core conversion to low CR fuel can be envisioned. Reference ABTR core designs with a rated power of 250 MWt were developed for ternary metal alloy and mixed oxide fuels based on WG-Pu feed. The reference core contains 54 driver, 6 test fuel, and 3 test material assemblies. For the startup core designs, the calculated TRU conversion ratio is 0.65 for the metal fuel core and 0.64 for the oxide fuel core. Both the metal and oxide cores show good performances. The metal fuel core requires an average TRU enrichment of 18.8% and yields a reactivity swing of 1.2 %{Delta}k over the 4-month cycle. The core average flux level is {approx}2.4 x 10{sup 15} n/cm{sup 2}s, and test assembly flux level is {approx}2.8 x 10{sup 15} n/cm{sup 2}s. Compared to the metal fuel core, the lower density oxide fuel core requires an average TRU enrichment of 21.8%, which results in a 780 kg TRU loading (as compared to 732 kg for metal) despite a {approx}9% smaller heavy metal inventory. The lower heavy metal inventory increases the burnup reactivity swing by {approx}10% and reduces the flux levels by {approx}8%. Alternative designs were also studied for a LWR-SF TRU feed and a low conversion ratio, including the recycle of the ABTR spent fuel TRU. The lower fissile contents of the LWR-SF TRU relative to the WG-Pu TRU significantly increase the required TRU enrichment of the startup cores to maintain the same cycle length. The even lower fissile fraction of the ABTR spent fuel TRU furt

  5. Organic Embedded Architecture for Sustainable FPGA Soft-Core Processors

    E-Print Network [OSTI]

    DeMara, Ronald F.

    Organic Embedded Architecture for Sustainable FPGA Soft-Core Processors KENING ZHANG, JAAFAR ________________________________________________________________________ An Organic Embedded System (OES) architecture is developed for sustainable performance using SRAM-based Field. In addition to simulation, the proposed OES architecture synthesized from HDL was prototyped on Xilinx Virtex

  6. accident core heatup: Topics by E-print Network

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

    accident core heatup First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Appendix 10 Spent Fuel Heatup Time...

  7. A Solid Core Heatpipe Reactor with Cylindrical Thermoelectric Converter Modules

    SciTech Connect (OSTI)

    Sayre, Edwin D. [218 Brooke Acres Drive, Los Gatos, CA 95032 (United States); Vaidyanathan, Sam [6663 Pomander Place, San Jose, CA 95120 (United States)

    2006-01-20T23:59:59.000Z

    A nuclear space power system that consists of a solid metal nuclear reactor core with heat pipes carrying energy to a cylindrical thermoelectric converter surrounding each of the heat pipes with a heat pipe radiator surrounding the thermoelectric converter is the most simple and reliable space power system. This means no single point of failure since each heat pipe and cylindrical converter is a separate power system and if one fails it will not affect the others. The heat pipe array in the solid core is designed so that if an isolated heat pipe or even two adjacent heat pipes fail, the remaining heat pipes will still transport the core heat without undue overheating of the uranium nitride fuel. The primary emphasis in this paper is on simplicity, reliability and fabricability of such a space nuclear power source. The core and heat pipes are made of Niobium 1% Zirconium alloy (Nb1Zr), with rhenium lined fuel tubes, bonded together by hot isostatic pressure (HIPing) and with sodium as the heat pipe working fluid, can be operated up to 1250K. The cylindrical thermoelectric converter is made by depositing the constituents of the converter around a Nb1%Zr tube and encasing it in a Nb 1% Zr alloy tube and HIPing the structure to get final bonding and to produce residual compressive stresses in all brittle materials in the converter. A radiator heat pipe filled with potassium that operates at 850K is bonded to the outside of the cylindrical converter for cooling. The solid core heat pipe and cylindrical converter are mated by welding during the final assembly. A solid core reactor with 150 heat pipes with a 0.650-inch (1.65 cm) ID and a 30-inch (76.2 cm) length with an output of 8 Watts per square inch as demonstrated by the SP100 PD2 cell tests will produce about 80 KW of electrical power. An advanced solid core reactor made with molybdenum 47% rhenium alloy, with lithium heat pipes and the PD2 theoretical output of 11 watts per square inch or advanced higher temperature converter to operate at 1350K could produce a greater output of approximately 100KW.

  8. ON THE INTERNAL DYNAMICS OF STARLESS CORES: STABILITY OF STARLESS CORES WITH INTERNAL MOTIONS AND COLLAPSE DYNAMICS

    SciTech Connect (OSTI)

    Seo, Young Min; Shirley, Yancy L. [Department of Astronomy and Steward Observatory, University of Arizona, Tucson, AZ (United States); Hong, Seung Soo [Astronomy Program, Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of)

    2013-05-20T23:59:59.000Z

    In order to understand the collapse dynamics of observed low-mass starless cores, we revise the conventional stability condition of hydrostatic Bonnor-Ebert spheres to take internal motions into account. Because observed starless cores resemble Bonnor-Ebert density structures, the stability and dynamics of the starless cores are frequently analyzed by comparing to the conventional stability condition of a hydrostatic Bonnor-Ebert sphere. However, starless cores are not hydrostatic but have observed internal motions. In this study, we take gaseous spheres with a homologous internal velocity field and derive stability conditions of the spheres utilizing a virial analysis. We propose two limiting models of spontaneous gravitational collapse: the collapse of critical Bonnor-Ebert spheres and uniform density spheres. The collapse of these two limiting models is intended to provide the lower and the upper limits, respectively, of the infall speeds for a given density structure. The results of our study suggest that the stability condition sensitively depends on internal motions. A homologous inward motion with a transonic speed can reduce the critical size compared to the static Bonnor-Ebert sphere by more than a factor of two. As an application of the two limiting models of spontaneous gravitational collapse, we compare the density structures and infall speeds of the observed starless cores L63, L1544, L1689B, and L694-2 to the two limiting models. L1689B and L694-2 seem to have been perturbed to result in faster infall motions than for spontaneous gravitational collapse.

  9. All Metal Iron Core For A Low Aspect Ratio Tokamak

    SciTech Connect (OSTI)

    D.A. Gates, C. Jun, I. Zatz, A. Zolfaghari

    2010-06-02T23:59:59.000Z

    A novel concept for incorporating a iron core transformer within a axisymmetric toroidal plasma containment device with a high neutron flux is described. This design enables conceptual design of low aspect ratio devices which employ standard transformer-driven plasma startup by using all-metal high resistance separators between the toroidal field windings. This design avoids the inherent problems of a multiturn air core transformer which will inevitably suffer from strong neutron bombardment and hence lose the integrity of its insulation, both through long term material degradation and short term neutron- induced conductivity.. A full 3-dimensional model of the concept has been developed within the MAXWELL program and the resultant loop voltage calculated. The utility of the result is found to be dependent on the resistivity of the high resistance separators. Useful loop voltage time histories have been obtained using achievable resistivities.

  10. NEUTRON RADIOGRAPHY (NRAD) REACTOR 64-ELEMENT CORE UPGRADE

    SciTech Connect (OSTI)

    John D. Bess

    2014-03-01T23:59:59.000Z

    The neutron radiography (NRAD) reactor is a 250 kW TRIGA (registered) (Training, Research, Isotopes, General Atomics) Mark II , tank-type research reactor currently located in the basement, below the main hot cell, of the Hot Fuel Examination Facility (HFEF) at the Idaho National Laboratory (INL). It is equipped with two beam tubes with separate radiography stations for the performance of neutron radiography irradiation on small test components. The interim critical configuration developed during the core upgrade, which contains only 62 fuel elements, has been evaluated as an acceptable benchmark experiment. The final 64-fuel-element operational core configuration of the NRAD LEU TRIGA reactor has also been evaluated as an acceptable benchmark experiment. Calculated eigenvalues differ significantly (approximately +/-1%) from the benchmark eigenvalue and have demonstrated sensitivity to the thermal scattering treatment of hydrogen in the U-Er-Zr-H fuel.

  11. Pulsed Magnetic Welding for Advanced Core and Cladding Steel

    SciTech Connect (OSTI)

    Cao, Guoping; Yang, Yong

    2013-12-19T23:59:59.000Z

    To investigate a solid-state joining method, pulsed magnetic welding (PMW), for welding the advanced core and cladding steels to be used in Generation IV systems, with a specific application for fuel pin end-plug welding. As another alternative solid state welding technique, pulsed magnetic welding (PMW) has not been extensively explored on the advanced steels. The resultant weld can be free from microstructure defects (pores, non-matallic inclusions, segregation of alloying elements). More specifically, the following objectives are to be achieved, 1) To design a suitable welding apparatus fixture, and optimize welding parameters for repeatable and acceptable joining of the fuel pin end-plug. The welding will be evaluated using tensile tests for lap joint weldments and helium leak tests for the fuel pin end-plug. 2) investigate the microstructural and mechanical properties changes in PMW weldments of proposed advanced core and cladding alloys. 3) Simulate the irradiation effects on the PWM weldments using ion irradiation.

  12. Support arrangements for core modules of nuclear reactors. [PWR

    DOE Patents [OSTI]

    Bollinger, L.R.

    1983-11-03T23:59:59.000Z

    A support arrangement is provided for the core modules of a nuclear reactor which provides support access through the control drive mechanisms of the reactor. This arrangement provides axial support of individual reactor core modules from the pressure vessel head in a manner which permits attachment and detachment of the modules from the head to be accomplished through the control drive mechanisms after their leadscrews have been removed. The arrangement includes a module support nut which is suspended from the pressure vessel head and screw threaded to the shroud housing for the module. A spline lock prevents loosening of the screw connection. An installation tool assembly, including a cell lifting and preloading tool and a torquing tool, fits through the control drive mechanism and provides lifting of the shroud housing while disconnecting the spline lock, as well as application of torque to the module support nut.

  13. Magnetorotational instability in cool cores of galaxy clusters

    E-Print Network [OSTI]

    Nipoti, C; Ettori, S; Bianconi, M

    2015-01-01T23:59:59.000Z

    Clusters of galaxies are embedded in halos of optically thin, gravitationally stratified, weakly magnetized plasma at the system's virial temperature. Due to radiative cooling and anisotropic heat conduction, such intracluster medium (ICM) is subject to local instabilities, which are combinations of the thermal, magnetothermal and heat-flux-driven buoyancy instabilities. If the ICM rotates significantly, its stability properties are substantially modified and, in particular, also the magnetorotational instability (MRI) can play an important role. We study simple models of rotating cool-core clusters and we demonstrate that the MRI can be the dominant instability over significant portions of the clusters, with possible implications for the dynamics and evolution of the cool cores. Our results give further motivation for measuring the rotation of the ICM with future X-ray missions such as ASTRO-H and ATHENA.

  14. MISALIGNMENT OF MAGNETIC FIELDS AND OUTFLOWS IN PROTOSTELLAR CORES

    SciTech Connect (OSTI)

    Hull, Charles L. H.; Plambeck, Richard L.; Bower, Geoffrey C.; Heiles, Carl; Meredith Hughes, A. [Astronomy Department and Radio Astronomy Laboratory, University of California, Berkeley, CA 94720-3411 (United States); Bolatto, Alberto D.; Jameson, Katherine; Mundy, Lee; Pound, Marc W. [Astronomy Department and Laboratory for Millimeter-wave Astronomy, University of Maryland, College Park, MD 20742 (United States); Carpenter, John M.; Lamb, James W.; Pillai, Thushara [Department of Astronomy, California Institute of Technology, 1200 E. California Blvd., MC 249-17, Pasadena, CA 91125 (United States); Crutcher, Richard M.; Hakobian, Nicholas S.; Kwon, Woojin; Looney, Leslie W. [Department of Astronomy, University of Illinois at Urbana-Champaign, 1002 W Green Street, Urbana, IL 61801 (United States); Fiege, Jason D.; Franzmann, Erica [Department of Physics and Astronomy, University of Manitoba, Winnipeg, MB R3T 2N2 (Canada); Houde, Martin [Department of Physics and Astronomy, University of Western Ontario, London, ON N6A 3K7 (Canada); Matthews, Brenda C., E-mail: chat@astro.berkeley.edu [Department of Physics and Astronomy, University of Victoria, 3800 Finnerty Rd., Victoria, BC V8P 5C2 (Canada); and others

    2013-05-10T23:59:59.000Z

    We present results of {lambda}1.3 mm dust-polarization observations toward 16 nearby, low-mass protostars, mapped with {approx}2.''5 resolution at CARMA. The results show that magnetic fields in protostellar cores on scales of {approx}1000 AU are not tightly aligned with outflows from the protostars. Rather, the data are consistent with scenarios where outflows and magnetic fields are preferentially misaligned (perpendicular), or where they are randomly aligned. If one assumes that outflows emerge along the rotation axes of circumstellar disks, and that the outflows have not disrupted the fields in the surrounding material, then our results imply that the disks are not aligned with the fields in the cores from which they formed.

  15. Laser cutting apparatus for nuclear core fuel subassembly

    DOE Patents [OSTI]

    Walch, Allan P. (Manchester, CT); Caruolo, Antonio B. (Vernon, CT)

    1982-02-23T23:59:59.000Z

    The object of the invention is to provide a system and apparatus which employs laser cutting to disassemble a nuclear core fuel subassembly. The apparatus includes a gantry frame (C) which straddles the core fuel subassembly (14), an x-carriage (22) travelling longitudinally above the frame which carries a focus head assembly (D) having a vertically moving carriage (46) and a laterally moving carriage (52), a system of laser beam transferring and focusing mirrors carried by the x-carriage and focusing head assembly, and a shroud follower (F) and longitudinal follower (G) for following the shape of shroud (14) to maintain a beam focal point (44) fixed upon the shroud surface for accurate cutting.

  16. Neutrinos and nucleosynthesis in core-collapse supernovae

    SciTech Connect (OSTI)

    Fröhlich, C.; Casanova, J. [Department of Physics, North Carolina State University, Raleigh, NC, 27695 (United States); Hempel, M.; Liebendörfer, M. [Departement für Physik, Universität Basel, CH-4056 Basel (Switzerland); Melton, C. A. [Department of Physics, North Carolina State University, Raleigh, NC 27695 (United States); Perego, A. [Institut für Kernphysik, Technische Universität Darmstadt, D-64289 Darmstadt (Germany)

    2014-01-01T23:59:59.000Z

    Massive stars (M > 8-10 M{sub ?}) undergo core collapse at the end of their life and explode as supernova with ~ 10?¹ erg of kinetic energy. While the detailed supernova explosion mechanism is still under investigation, reliable nucleosynthesis calculations based on successful explosions are needed to explain the observed abundances in metal-poor stars and to predict supernova yields for galactic chemical evolution studies. To predict nucleosynthesis yields for a large number of progenitor stars, computationally efficient explosion models are required. We model the core collapse, bounce and subsequent explosion of massive stars assuming spherical symmetry and using detailed microphysics and neutrino physics combined with a novel method to artificially trigger the explosion (PUSH). We discuss the role of neutrinos, the conditions in the ejecta, and the resulting nucleosynthesis.

  17. Magnetized neutron stars with superconducting cores: Effect of entrainment

    E-Print Network [OSTI]

    Palapanidis, K; Lander, S K

    2015-01-01T23:59:59.000Z

    We construct equilibrium configurations of magnetized, two-fluid neutron stars using an iterative numerical method. We assume that the neutron star has two regions: the core, which is modelled as a two-component fluid consisting of type-II superconducting protons and superfluid neutrons, and the crust, a region composed of normal matter. Taking a new step towards more complete equilibrium models, we include the effect of entrainment, which implies that a magnetic force acts on neutrons, too. We consider purely poloidal field cases and present improvements to an earlier numerical scheme for solving equilibrium equations, by introducing new convergence criteria. We find that entrainment results in qualitative differences in the structure of field lines across the crust-core boundary and along the magnetic axis.

  18. Core-Collapse Supernovae Induced by Anisotropic Neutrino Radiation

    E-Print Network [OSTI]

    Yuko Motizuki; Hideki Madokoro; Tetsuya Shimizu

    2004-06-11T23:59:59.000Z

    We demonstrate the important role of anisotropic neutrino radiation on the mechanism of core-collapse supernova explosions. Through a new parameter study with a fixed radiation field of neutrinos, we show that prolate explosions caused by globally anisotropic neutrino radiation is the most effective mechanism of increasing the explosion energy when the total neutrino luminosity is given. This is suggestive of the fact that the expanding materials of SN 1987A has a prolate geometry.

  19. Multidimensional, multiphysics simulations of core-collapse supernovae

    SciTech Connect (OSTI)

    Messer, Bronson [ORNL; Mezzacappa, Anthony [ORNL; Blondin, J. M. [North Carolina State University; Bruenn, S. W. [Florida Atlantic University; Hix, William Raphael [ORNL

    2008-01-01T23:59:59.000Z

    CHIMERA is a multi-dimensional radiation hydrodynamics code designed to study core-collapse supernovae. The code is made up of three essentially independent parts: a hydrodynamics module, a nuclear burning module, and a neutrino transport solver combined within an operator-split approach. We review the code's architecture and some recently improved implementations used in the code. We also briefly discuss preliminary results obtained with the code in three spatial dimensions.

  20. Multidimensional, multiphysics simulations of core-collapse supernovae

    SciTech Connect (OSTI)

    Messer, Bronson [ORNL; Mezzacappa, Anthony [ORNL; Blondin, J. M. [North Carolina State University; Bruenn, S. W. [Florida Atlantic University; Hix, William Raphael [ORNL

    2008-01-01T23:59:59.000Z

    CHIMERA is a multi-dimensional radiation hydrodynamics code designed to study core-collapse supernovae. The code is made up of three essentially independent parts: a hydrodynamics module, a nuclear burning module, and a neutrino transport solver combined within an operator-split approach. We review the code s architecture and some recently improved implementations used in the code. We also briefly discuss preliminary results obtained with the code in three spatial dimensions.

  1. Multimessengers from 3D Core-Collapse Supernovae

    E-Print Network [OSTI]

    Yakunin, Konstantin N; Mezzacappa, Anthony; Messer, O E Bronson; Lentz, Eric J; Bruenn, Stephen W; Hix, W Rafael; Harris, J Austin

    2015-01-01T23:59:59.000Z

    We present gravitational wave and neutrino signatures obtained in our first principle 3D core-collapse supernova simulation of 15M non-rotating progenitor with Chimera code. Observations of neutrinos emitted by the forming neutron star, and gravitational waves, which are produced by hydrodynamic instabilities is the only way to get direct information about the supernova engine. Both GW and neutrino signals show different phases of supernova evolution.

  2. The Enzyme-mimic Activity of Ferric Nano-Core Residing in Ferritin...

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

    The Enzyme-mimic Activity of Ferric Nano-Core Residing in Ferritin and Its Biosensing Applications. The Enzyme-mimic Activity of Ferric Nano-Core Residing in Ferritin and Its...

  3. Excited Carrier Dynamics of ?-Cr2O3/?-Fe2O3 Core...

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

    Excited Carrier Dynamics of ?-Cr2O3?-Fe2O3 Core-Shell Nanostructures. Excited Carrier Dynamics of ?-Cr2O3?-Fe2O3 Core-Shell Nanostructures. Abstract: In...

  4. Ion irradiation of Fe-Fe oxide core-shell nanocluster films:...

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

    irradiation of Fe-Fe oxide core-shell nanocluster films: Effect of interface on stability of magnetic properties. Ion irradiation of Fe-Fe oxide core-shell nanocluster films:...

  5. Size dependence of inter- and intra-cluster interactions in core...

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

    Size dependence of inter- and intra-cluster interactions in core-shell iron-iron oxide nanoclusters. Size dependence of inter- and intra-cluster interactions in core-shell...

  6. Hollow Core-Shell Structured Porous Si-C Nanocomposites for Li...

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

    Hollow Core-Shell Structured Porous Si-C Nanocomposites for Li-Ion Battery Anodes. Hollow Core-Shell Structured Porous Si-C Nanocomposites for Li-Ion Battery Anodes. Abstract:...

  7. Eects of thermo-chemical mantle convection on the thermal evolution of the Earth's core

    E-Print Network [OSTI]

    Tackley, Paul J.

    E¡ects of thermo-chemical mantle convection on the thermal evolution of the Earth's core Takashi in the core with a fully dynamic thermo-chemical mantle convection model is developed to investigate

  8. Neutral carbohydrate geochemistry of particulate material (trap and core sediments) in an eutrophic lake (Aydat,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Neutral carbohydrate geochemistry of particulate material (trap and core sediments) in an eutrophic Carbohydrate compositions were determined on sinking particles and core samples from eutrophic lake Aydat; Eutrophic lake; Aydat lake 1. Introduction Polysaccharides are common structural and storage polymers

  9. A sequential partly iterative approach for multicomponent reactive transport with CORE2D

    E-Print Network [OSTI]

    Samper, J.

    2009-01-01T23:59:59.000Z

    Juncosa R. , Delgado J. and Montenegro L. (2000) CORE 2D : App. Samper, J. , Yang, C. , Montenegro, L. , 2003. CORE 2DSamper, J. , Zhang, G. , Montenegro, L. , 2006a. Coupled

  10. andrill and-1b core: Topics by E-print Network

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

    cyclic cohomology of corings on which para Hopf algebroids act. Bahram Rangipour (OSU; Ohio; US) 14 Towards Principled Core Ontologies CiteSeer Summary: An important issue in the...

  11. Best Practices for Teaching Core Competencies to Baldrige Examiners in State Baldrige Programs

    E-Print Network [OSTI]

    Brooks, Sandra E.

    2011-08-08T23:59:59.000Z

    The purpose of this study was to determine the core competencies needed by state Baldrige examiners, to identify best practices in examiner training programs provided by state Baldrige organizations, and to identify best practices for teaching core...

  12. FRESH INSIGHTS ON THE STRUCTURE OF THE SOLAR CORE

    SciTech Connect (OSTI)

    Basu, Sarbani [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States); Chaplin, William J.; Elsworth, Yvonne [School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); New, Roger [Faculty of Arts, Computing, Engineering and Sciences, Sheffield Hallam University, Sheffield S1 1WB (United Kingdom); Serenelli, Aldo M. [Max Planck Institute for Astrophysics K. Schwarzschild Str. 1, Garching, D-85471 (Germany)], E-mail: sarbani.basu@yale.edu, E-mail: w.j.chaplin@bham.ac.uk, E-mail: y.p.elsworth@bham.ac.uk, E-mail: r.new@shu.ac.uk, E-mail: aldos@mpa-garching.mpg.de

    2009-07-10T23:59:59.000Z

    We present new results on the structure of the solar core, obtained with new sets of frequencies of solar low-degree p modes obtained from the BiSON network. We find that different methods used in extracting the different sets of frequencies cause shifts in frequencies, but the shifts are not large enough to affect solar structure results. We find that the BiSON frequencies show that the solar sound speed in the core is slightly larger than that inferred from data from Michelson Doppler Imager low-degree modes, and the uncertainties on the inversion results are smaller. Density results also change by a larger amount, and we find that solar models now tend to show smaller differences in density compared to the Sun. The result is seen at all radii, a result of the fact that conservation of mass implies that density differences in one region have to cancel out density differences in others, since our models are constructed to have the same mass as the Sun. The uncertainties on the density results are much smaller too. We attribute the change in results to having more, and lower frequency, low-degree mode frequencies available. These modes provide greater sensitivity to conditions in the core.

  13. Sustained concrete attack by low-temperature, fragmented core debris

    SciTech Connect (OSTI)

    Tarbell, W.W.; Bradley, D.R.; Blose, R.E.; Ross, J.W.; Gilbert, D.W.

    1987-07-01T23:59:59.000Z

    Four experiments were performed to study the interactions between low-temperature core debris and concretes typical of reactor structures. The tests addressed accident situations where the core debris is at elevated temperature, but not molten. Concrete crucibles were formed in right-circular cylinders with 45 kg of steel spheres (approx.3-mm diameter) as the debris simulant. The debris was heated by an inductive power supply to nominal temperatures of 1473 K to 1673 K. Two tests were performed on each of two concrete types using either basalt or limestone aggregate. For each concrete, one test was performed with water atop the debris while the second had no water added. The results show that low-temperature core debris will erode either basalt or limestone-common sand concretes. Downward erosion rates of 3 to 4 cm/hr were recorded for both concrete types. The limestone concrete produced a crust layer within the debris bed that was effective in preventing the downward intrusion of water. The basalt concrete crust was formed above the debris and consisted of numerous, convoluted, thin layers. Carbon dioxide and water release from the decomposition of concrete were partially reduced by the metallic debris to yield carbon monoxide and hydrogen, respectively. The overlying water pool did not effect the reduction reactions.

  14. Application of Covariances to Fast Reactor Core Analysis

    SciTech Connect (OSTI)

    Ishikawa, M. [Japan Atomic Energy Agency (JAEA), O-arai, Ibaraki, 311-1393 (Japan)], E-mail: ishikawa.makoto@jaea.go.jp

    2008-12-15T23:59:59.000Z

    In the present paper, the current status of covariance applications to fast reactor analysis and design is summarized with actual examples. The covariance applications are classified into three fields. First, covariances are used to quantify the uncertainty of nuclear core parameters such as criticality, control rod worth, reaction rate ratio, power distribution, sodium void reactivity, etc. The special features of the Japanese case are to include both the burnup-related parameters such as burnup reactivity loss or fuel composition changes, and the temperature-related parameter, that is, the Doppler reactivity. Second, covariances are used to select the important nuclides, reactions and energy ranges which are dominant to the uncertainty of core parameters, and to give nuclear scientists recommendations to improve the accuracy of the data. Finally, covariances are used to improve the accuracy of core design values by adopting the integral data such as the critical experiments and the power reactor operation data. The way toward improvement is classified into the conventional E/C (Experiment/Calculation) bias method and the more comprehensive cross section adjustment based on the Bayesian theorem and the generalized least square method. In Japan, an adjusted group-constant set, ADJ2000R, is now being used in the design work for future fast reactors.

  15. Natural thorium isotopes in marine sediment core off Labuan port

    SciTech Connect (OSTI)

    Hafidz, B. Y.; Asnor, A. S.; Terence, R. C.; Mohamed, C. A. R. [School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia 43600, Bangi, Selangor (Malaysia)

    2014-02-12T23:59:59.000Z

    Sediment core was collected from Labuan port and analyzed to determine the radioactivity of thorium (Th) isotopes. The objectives of this study are to determine the possible sources of Th isotopes at Labuan port and estimates the sedimentation rate based on {sup 228}Th/{sup 232}Th model. The results suggest the {sup 230}Th and {sup 232}Th might be originated from terrestrial sedimentary rock while {sup 228}Th originated by authigenic origin. High ratio value of {sup 230}Th/{sup 232}Th detected at the top surface sediment indicates the increasing of {sup 230}Th at the recent years which might be contributed from the anthropogenic sources. The sedimentation rate of core sediment from Labuan Port was successfully estimated by using {sup 228}Th/{sup 232}Th model. The result show high sedimentation rate with 4.67 cm/year indicates rapid deposition occurred at this study area due to the high physical activity at the Labuan port. By assume the constant sedimentation rate at this area; we estimated the age of 142 cm core sediment obtained from Labuan port is 32 years started from 1981 to 2012. This chronology will be used in forthcoming research to investigate the historical profile of anthropogenic activities affecting the Labuan port.

  16. Application of an artificial neural network to reactor core analysis

    SciTech Connect (OSTI)

    Seung Hwan Seong; Un Chul Lee [Seoul National Univ. (Korea, Republic of)

    1995-12-31T23:59:59.000Z

    To analyze three-dimensional reactor core behaviors, the finite difference or the finite element method have generally been used. Nodal method is adopted as another tool for analyzing transient core characteristics. These methods, however, require much calculation time to solve very complicated iterations for better convergence. Especially when the transient states are to be predicted, none of these methods can meet the requirements within the time span in which the operator can react. To overcome these difficulties, a new analytic model based on the artificial neural networks (ANNs) is suggested. Because trained ANNs are capable of modeling the input/output relationships of a nonlinear system without complex analogy, they are able to map the power distributions and calculate the eigenvalue corresponding to the core conditions in a short time and utilize the previous results by updating the weights of inter-connection between input and output patterns. To confirm the accuracy and capability, daily load-follow operation in a pressurized water reactor (PWR) is simulated using the new analytic model.

  17. The origin of complex organic molecules in prestellar cores

    E-Print Network [OSTI]

    Vastel, Charlotte; Lefloch, Bertrand; Bachiller, Raphael

    2014-01-01T23:59:59.000Z

    Complex organic molecules (COMs) have been detected in a variety of environments, including cold prestellar cores. Given the low temperature of these objects, these last detections challenge existing models. We report here new observations towards the prestellar core L1544. They are based on an unbiased spectral survey of the 3mm band at the IRAM-30m telescope, as part of the Large Program ASAI. The observations allow us to provide the full census of the oxygen bearing COMs in this source. We detected tricarbon monoxide, methanol, acetaldehyde, formic acid, ketene, and propyne with abundances varying from 5e-11 to 6e-9. The non-LTE analysis of the methanol lines shows that they are likely emitted at the border of the core, at a radius of ~8000 AU where T~10 K and nH2~2e4 cm-3. Previous works have shown that water vapour is enhanced in the same region because of the photodesorption of water ices. We propose that a non-thermal desorption mechanism is also responsible for the observed emission of methanol and CO...

  18. Beamed Core Antimatter Propulsion: Engine Design and Optimization

    E-Print Network [OSTI]

    Ronan Keane; Wei-Ming Zhang

    2012-05-16T23:59:59.000Z

    A conceptual design for beamed core antimatter propulsion is reported, where electrically charged annihilation products directly generate thrust after being deflected and collimated by a magnetic nozzle. Simulations were carried out using the Geant4 (Geometry and tracking) software toolkit released by the CERN accelerator laboratory for Monte Carlo simulation of the interaction of particles with matter and fields. Geant permits a more sophisticated and comprehensive design and optimization of antimatter engines than the software environment for simulations reported by prior researchers. The main finding is that effective exhaust speeds Ve ~ 0.69c (where c is the speed of light) are feasible for charged pions in beamed core propulsion, a major improvement over the Ve ~ 0.33c estimate based on prior simulations. The improvement resulted from optimization of the geometry and the field configuration of the magnetic nozzle. Moreover, this improved performance is realized using a magnetic field on the order of 10 T at the location of its highest magnitude. Such a field could be produced with today's technology, whereas prior nozzle designs anticipated and required major advances in this area. The paper also briefly reviews prospects for production of the fuel needed for a beamed core engine.

  19. automatically generated multi-core: Topics by E-print Network

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

    applications is not suited to multi-core architectures. The Algorithm Architecture Matching (AAM) methodology optimizes static application implementation on...

  20. Collapse mechanisms of sandwich beams with composite faces and a foam core,

    E-Print Network [OSTI]

    Fleck, Norman A.

    - strated for aluminium alloy face sheets and polymeric foam cores, it has since been extended to other

  1. Axion dark matter, solitons, and the cusp-core problem

    E-Print Network [OSTI]

    David J. E. Marsh; Ana-Roxana Pop

    2015-06-17T23:59:59.000Z

    Self-gravitating bosonic fields can support stable and localised field configurations. For real fields, these solutions oscillate in time and are known as oscillatons. The density profile is static, and is soliton. Such solitons should be ubiquitous in models of axion dark matter, with the soliton characteristic mass and size depending on some inverse power of the axion mass. Stable configurations of non-relativistic axions are studied numerically using the Schr\\"{o}dinger-Poisson system. This method, and the resulting soliton density profiles, are reviewed. Using a scaling symmetry and the uncertainty principle, the core size of the soliton can be related to the central density and axion mass, $m_a$, in a universal way. Solitons have a constant central density due to pressure-support, unlike the cuspy profile of cold dark matter (CDM). One consequence of this fact is that solitons composed of ultra-light axions (ULAs) may resolve the `cusp-core' problem of CDM. In DM halos, thermodynamics will lead to a CDM-like Navarro-Frenk-White profile at large radii, with a central soliton core at small radii. Using Monte-Carlo techniques to explore the possible density profiles of this form, a fit to stellar-kinematical data of dwarf spheroidal galaxies is performed. In order for ULAs to resolve the cusp-core problem (without recourse to baryon feedback or other astrophysical effects) the axion mass must satisfy $m_a<1.1\\times 10^{-22}\\text{ eV}$ at 95\\% C.L. On the other hand, ULAs with $m_a\\lesssim 1\\times 10^{-22}\\text{ eV}$ are in some tension with cosmological structure formation. An axion solution to the cusp-core problem thus makes novel predictions for future measurements of the epoch of reionisation. On the other hand, this can be seen as evidence that structure formation could soon impose a \\emph{Catch 22} on axion/scalar field DM, similar to the case of warm DM.

  2. Analysis of core samples from the BPXA-DOE-USGS Mount Elbert gas hydrate stratigraphic test well: Insights into core disturbance and handling

    SciTech Connect (OSTI)

    Kneafsey, Timothy J.; Lu, Hailong; Winters, William; Boswell, Ray; Hunter, Robert; Collett, Timothy S.

    2009-09-01T23:59:59.000Z

    Collecting and preserving undamaged core samples containing gas hydrates from depth is difficult because of the pressure and temperature changes encountered upon retrieval. Hydrate-bearing core samples were collected at the BPXA-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well in February 2007. Coring was performed while using a custom oil-based drilling mud, and the cores were retrieved by a wireline. The samples were characterized and subsampled at the surface under ambient winter arctic conditions. Samples thought to be hydrate bearing were preserved either by immersion in liquid nitrogen (LN), or by storage under methane pressure at ambient arctic conditions, and later depressurized and immersed in LN. Eleven core samples from hydrate-bearing zones were scanned using x-ray computed tomography to examine core structure and homogeneity. Features observed include radial fractures, spalling-type fractures, and reduced density near the periphery. These features were induced during sample collection, handling, and preservation. Isotopic analysis of the methane from hydrate in an initially LN-preserved core and a pressure-preserved core indicate that secondary hydrate formation occurred throughout the pressurized core, whereas none occurred in the LN-preserved core, however no hydrate was found near the periphery of the LN-preserved core. To replicate some aspects of the preservation methods, natural and laboratory-made saturated porous media samples were frozen in a variety of ways, with radial fractures observed in some LN-frozen sands, and needle-like ice crystals forming in slowly frozen clay-rich sediments. Suggestions for hydrate-bearing core preservation are presented.

  3. NANO EXPRESS Open Access Au/Pd core-shell nanoparticles with varied hollow

    E-Print Network [OSTI]

    Liu, Fuqiang

    NANO EXPRESS Open Access Au/Pd core-shell nanoparticles with varied hollow Au cores for enhanced has been developed to synthesize Au/Pd core-shell nanoparticles via galvanic replacement of Cu by Pd on hollow Au nanospheres. The unique nanoparticles were characterized by X-ray diffraction, X

  4. Idealized test cases for the dynamical cores of Atmospheric General Circulation Models

    E-Print Network [OSTI]

    Jablonowski, Christiane

    Idealized test cases for the dynamical cores of Atmospheric General Circulation Models: A proposal) Ram Nair (NCAR) Mark Taylor (Sandia National Laboratory) May/29/2008 1 Idealized test cases for 3D dynamical cores This document describes the idealized dynamical core test cases that are proposed

  5. General Behavioral Thermal Modeling and Characterization for Multi-core Microprocessor Design

    E-Print Network [OSTI]

    Tan, Sheldon X.-D.

    General Behavioral Thermal Modeling and Characterization for Multi-core Microprocessor Design Thom-performance multi-core microprocessor design. The new approach builds the thermal behavioral models from ability. Experimental results on a real quad-core microprocessor show that ThermSID is more accurate than

  6. Sources of uncertainty in ice core data A contribution to the Workshop on

    E-Print Network [OSTI]

    Sources of uncertainty in ice core data A contribution to the Workshop on Reducing and Representing - 11, 2008 Eric J. Steig, University of Washington Seattle, WA 98195 1. Background Ice cores provide of these species (among them aerosols and greenhouse gases, and of course snow accumulation). Ice core records

  7. Chemical concentration measurement in blood serum and urine samples using liquid-core optical fiber Raman

    E-Print Network [OSTI]

    Berger, Andrew J.

    Chemical concentration measurement in blood serum and urine samples using liquid-core optical fiber in clinical blood serum and urine samples using liquid-core optical fiber (LCOF) Raman spectroscopy-core optical fiber (LCOF) geome- try can enhance the collected Raman signal from nonturbid aqueous samples by 1

  8. Correction method for absorption-dependent signal enhancement by a liquid-core optical fiber

    E-Print Network [OSTI]

    Berger, Andrew J.

    Correction method for absorption-dependent signal enhancement by a liquid-core optical fiber Dahu-core optical fiber (LCOF) geometry is absorption dependent. This dependence leads to a disruption of the usual refractive index, a liquid-core optical fiber (LCOF) is formed. Light rays within the critical angle can

  9. Deep Infrared Imaging of the R Coronae Australis Cloud Core Bruce A. Wilking

    E-Print Network [OSTI]

    Wilking, Bruce A.

    Deep Infrared Imaging of the R Coronae Australis Cloud Core Bruce A. Wilking Department of Physics hzinnecker@aip.de ABSTRACT Infrared images of the R Coronae Australis molecular core in broad­band J, H through about 80% of the depth of the molecular core. As few as 22, and as many as 40, sources

  10. Characterization of Composite Cores for High Temperature-Low Sag (HTLS)

    E-Print Network [OSTI]

    Characterization of Composite Cores for High Temperature-Low Sag (HTLS) Conductors Final Project project T-33 titled "Characterization of Composite Cores for High Temperature-Low Sag (HTLS) Conductors/University Cooperative Research Center since 1996 PSERC #12;Characterization of Composite Cores for High Temperature-Low

  11. IEC Device Core Physics Explorations* John F. Santarius and Gilbert A. Emmert

    E-Print Network [OSTI]

    IEC Device Core Physics Explorations* John F. Santarius and Gilbert A. Emmert Fusion Technology Institute 2 IEC Core Explorations for Spherically Converging Ions in the Presence of Grid Wires Early Analyses of IEC Core Convergence Predicted Potential Structures · R.L. Hirsch, "Inertial

  12. k-core (bootstrap) percolation on complex networks: Critical phenomena and nonlocal effects

    E-Print Network [OSTI]

    A. V. Goltsev; S. N. Dorogovtsev; J. F. F. Mendes

    2006-02-28T23:59:59.000Z

    We develop the theory of the k-core (bootstrap) percolation on uncorrelated random networks with arbitrary degree distributions. We show that the k-core percolation is an unusual, hybrid phase transition with a jump emergence of the k-core as at a first order phase transition but also with a critical singularity as at a continuous transition. We describe the properties of the k-core, explain the meaning of the order parameter for the k-core percolation, and reveal the origin of the specific critical phenomena. We demonstrate that a so-called ``corona'' of the k-core plays a crucial role (corona is a subset of vertices in the k-core which have exactly k neighbors in the k-core). It turns out that the k-core percolation threshold is at the same time the percolation threshold of finite corona clusters. The mean separation of vertices in corona clusters plays the role of the correlation length and diverges at the critical point. We show that a random removal of even one vertex from the k-core may result in the collapse of a vast region of the k-core around the removed vertex. The mean size of this region diverges at the critical point. We find an exact mapping of the k-core percolation to a model of cooperative relaxation. This model undergoes critical relaxation with a divergent rate at some critical moment.

  13. Detecting shape defects in ferrite cores \\Lambda Dmitry Chetverikov and Judit Verest'oy

    E-Print Network [OSTI]

    Chetverikov, Dmitry

    Detecting shape defects in ferrite cores \\Lambda Dmitry Chetverikov and Judit Verest'oy Computer of the objects. The method is applied to the visual inspection and dimensional measurement of ferrite cores CIPA­CT94 0153 CRASH (for CRAck and SHape defect detection in ferrite cores) which has been in progress

  14. Accurate Prediction of Ferrite Core Loss with Nonsinusoidal Waveforms Using Only Steinmetz

    E-Print Network [OSTI]

    Accurate Prediction of Ferrite Core Loss with Nonsinusoidal Waveforms Using Only Steinmetz IN POWER ELECTRONICS 1 Accurate Prediction of Ferrite Core Loss with Nonsinusoidal Waveforms Using Only of ferrite core loss for nonsinu- soidal waveforms separates a flux trajectory into major and minor loops via

  15. 216-Day report for Tank 241-C-111, cores 58 and 59

    SciTech Connect (OSTI)

    Rice, A.D.

    1994-12-05T23:59:59.000Z

    Three core samples from tank C-111, and a field blank, were received by the 222-S laboratories. Cores 58, 59, and the field blank were analyzed in accordance with plans. A hot cell blank was analyzed at the direction of the hot cell chemist. No sample results exceeded the notification limits. Core 60 was not analyzed.

  16. Long-term records of atmospheric deposition of mercury in peat cores

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Long-term records of atmospheric deposition of mercury in peat cores from Arctic, and comparisonD dissertation February 2004 #12;Long-term records of atmospheric deposition of mercury in peat cores from Arctic in southern Ontario recorded by peat cores from three bogs: comparison with natural "background" values (past

  17. Data Locality Optimization for Synthesis of Efficient Out-of-Core Algorithms

    E-Print Network [OSTI]

    Baumgartner, Gerald

    Data Locality Optimization for Synthesis of Efficient Out-of-Core Algorithms Sandhya Krishnan1,choppellav @ornl.gov Abstract. This paper describes an approach to synthesis of efficient out-of-core code for the generation of out-of-core code. Experimental measurements are provided that show a good match with model

  18. Data Locality Optimization for Synthesis of Efficient Out-of-Core Algorithms

    E-Print Network [OSTI]

    Ramanujam, J. "Ram"

    Data Locality Optimization for Synthesis of Efficient Out-of-Core Algorithms Sandhya Krishnan1,choppellav}@ornl.gov Abstract. This paper describes an approach to synthesis of efficient out-of-core code for a class for the generation of out-of-core code. Experimental measurements are provided that show a good match with model

  19. A Core Grid Ontology for the Semantic Grid Wei Xing Marios D. Dikaiakos

    E-Print Network [OSTI]

    Pallis, George

    A Core Grid Ontology for the Semantic Grid Wei Xing Marios D. Dikaiakos Department of Computer, we propose a Core Grid Ontology (CGO) that defines fundamental Grid-specific concepts, and the re- lationships between them. One of the key goals is to make this Core Grid Ontology general enough and easily

  20. An Algorithm for In-Core Frequent Itemset Mining on Streaming Data Ruoming Jin Gagan Agrawal

    E-Print Network [OSTI]

    Agrawal, Gagan

    .ohio-state.edu Abstract Frequent itemset mining is a core data mining operation and has been extensively studied over Frequent itemset mining is a core data mining operation and has been extensively studied over the lastAn Algorithm for In-Core Frequent Itemset Mining on Streaming Data Ruoming Jin Gagan Agrawal

  1. AUGUST 2014 | DALHOUSIE BRAND GUIDE AND TOOL KIT 3.0 CORE LOGO AND

    E-Print Network [OSTI]

    Lotze, Heike K.

    AUGUST 2014 | DALHOUSIE BRAND GUIDE AND TOOL KIT 3.0 CORE LOGO AND EXTENSIONS 3.01 USING YOUR 2014 | DALHOUSIE BRAND GUIDE AND TOOL KIT 3.0 CORE LOGO AND EXTENSIONS | 3.01 USING YOUR FACULTY NAME of Dalhousie core brand logo extensions, these logos will be created and provided to you by Creative Services

  2. Thermal hydraulics analysis of the MIT research reactor in support of a low enrichment uranium (LEU) core conversion

    E-Print Network [OSTI]

    Ko, Yu-Chih, Ph. D. Massachusetts Institute of Technology

    2008-01-01T23:59:59.000Z

    The MIT research reactor (MITR) is converting from the existing high enrichment uranium (HEU) core to a low enrichment uranium (LEU) core using a high-density monolithic UMo fuel. The design of an optimum LEU core for the ...

  3. Technically superior but unloved : a multi-faceted perspective on multi-core's failure to meet expectations in embedded systems

    E-Print Network [OSTI]

    Ledger, Dan

    2011-01-01T23:59:59.000Z

    A growing number of embedded multi-core processors from several vendors now offer several technical advantages over single-core architectures. However, despite these advantages, adoption of multi-core processors in embedded ...

  4. BMUS PROGRAMME Each small square box represents 0.5 unit. The shaded areas are the core

    E-Print Network [OSTI]

    Sheldon, Nathan D.

    BMUS PROGRAMME Each small square box represents 0.5 unit. The shaded areas are the core component of each year. The optional component can be made up of 0.5 units or whole units of Intermediate (I unit) Core 1102 (1 unit) Core 1103 (0.5 unit) Core 1104 (0.5 unit) Core 1105 (0.5 unit) Core 1106 (0.5

  5. CN-Cycle Solar Neutrinos and Sun's Primordial Core Metalicity

    E-Print Network [OSTI]

    W. C. Haxton; A. M. Serenelli

    2008-05-14T23:59:59.000Z

    We argue that it may be possible to exploit neutrinos from the CN cycle and pp chain to determine the primordial solar core abundances of C and N at an interesting level of precision. Such a measurement would allow a comparison of the Sun's deep interior composition with it surface, testing a key assumption of the standard solar model (SSM), a homogeneous zero-age Sun. It would also provide a cross-check on recent photospheric abundance determinations that have altered the once excellent agreement between the SSM and helioseismology. As further motivation, we discuss a speculative possibility in which photospheric abundance/helioseismology puzzle is connected with the solar-system metal differentiation that accompanied formation of the gaseous giant planets. The theoretical relationship between core C and N and the 13N and 15O solar neutrino fluxes can be made more precise (and more general) by making use of the Super-Kamiokande and SNO 8B neutrino capture rates, which calibrate the temperature of the solar core. The primordial C and N abundances can then be obtained from these neutrino fluxes and from a product of nuclear rates, with little residual solar model dependence. We describe some of the recent experimental advances that could allow this comparison to be made (theoretically) at about the 9% level, and note that this uncertainty may be reduced further due to ongoing work on the S-factor for 14N(p,gamma). The envisioned measurement might be possible in deep, large-volume detectors using organic scintillator, e.g., Borexino or SNO+

  6. Challenges for coring deep permafrost on earth and mars

    SciTech Connect (OSTI)

    Pfiffner, Susan Marie [ORNL; Onstott, Tullis [Princeton University; Ruskeeniemi, T [Geological Survey of Finland; Talikka, M [Geological Survey of Finland; Bakermans, Corien [Michigan State University, East Lansing; McGown, Daniel [Princeton University; Chan, E. [Princeton University; Johnson, Adam [Indiana University; Phelps, Tommy Joe [ORNL; Le Puil, M [University of Tennessee, Knoxville (UTK); Difurio, Sarah A [ORNL; Pratt, L.M. [Indiana University; Stotler, R [University of Waterloo, Canada; Frape, S [University of Waterloo, Canada; Telling, J [University of Toronto; Lollar, Barbara Sherwood [University of Toronto; Neill, I [Wolfden Resources, Inc., Ontario, Canada; Zerbin, B [Major Drilling Group International, Inc., Manitoba, Canada

    2008-01-01T23:59:59.000Z

    A scientific drilling expedition to the High Lake region of Nunavut, Canada, was recently completed with the goals of collecting samples and delineating gradients in salinity, gas composition, pH, pe, and microbial abundance in a 400 m thick permafrost zone and accessing the underlying pristine subpermafrost brine. With a triple-barrel wireline tool and the use of stringent quality assurance and quality control (QA/QC) protocols, 200 m of frozen, Archean, mafic volcanic rock was collected from the lower boundary that separates the permafrost layer and subpermafrost saline water. Hot water was used to remove cuttings and prevent the drill rods from freezing in place. No cryopegs were detected during penetration through the permafrost. Coring stopped at the 535 m depth, and the drill water was bailed from the hole while saline water replaced it. Within 24 hours, the borehole iced closed at 125 m depth due to vapor condensation from atmospheric moisture and, initially, warm water leaking through the casing, which blocked further access. Preliminary data suggest that the recovered cores contain viable anaerobic microorganisms that are not contaminants even though isotopic analyses of the saline borehole water suggests that it is a residue of the drilling brine used to remove the ice from the upper, older portion of the borehole. Any proposed coring mission to Mars that seeks to access subpermafrost brine will not only require borehole stability but also a means by which to generate substantial heating along the borehole string to prevent closure of the borehole from condensation of water vapor generated by drilling.

  7. Core Overshoot: An Improved Treatment and Constraints from Seismic Data

    E-Print Network [OSTI]

    Christian W. Straka; Pierre Demarque; D. B. Guenther

    2005-05-01T23:59:59.000Z

    We present a comprehensive set of stellar evolution models for Procyon A in an effort to guide future measurements of both traditional stellar parameters and seismic frequencies towards constraining the amount of core overshoot in Procyon A and possibly other stars. Current observational measurements of Procyon A when combined with traditional stellar modeling only place a large upper limit on overshoot of alphaOV < 1.1. By carrying out a detailed pulsation analysis, we further demonstrate, how p- and g-mode averaged spacings can be used to gain better estimates of the core size. For both p- and g-modes, the frequency spacings for models without overshoot are clearly separated from the models with overshoot. In addition, measurements of the l=0 averaged small p-mode spacings could be used to establish Procyon A's evolutionary stage. For a fixed implementation of overshoot and under favorable circumstances, the g-mode spacings can be used to determine the overshoot extent to an accuracy of +-0.05 Hp. However, we stress that considerable confusion is added due to the unknown treatment of the overshoot region. This ambiguity might be removed by analyzing many different stars. A simple non-local convection theory developed by Kuhfuss is implemented in our stellar evolution code and contrasted with the traditional approaches. We show that this theory supports a moderate increase of the amount of convective overshoot with stellar mass of Delta(alphaOV) = +0.10 between 1.5 Msun and 15 Msun. This theory places an upper limit on Procyon A's core overshoot extent of ~0.4 Hp which matches the limit imposed by Roxburgh's integral criterion.

  8. A computer program to determine the specific power of prismatic-core reactors

    SciTech Connect (OSTI)

    Dobranich, D.

    1987-05-01T23:59:59.000Z

    A computer program has been developed to determine the maximum specific power for prismatic-core reactors as a function of maximum allowable fuel temperature, core pressure drop, and coolant velocity. The prismatic-core reactors consist of hexagonally shaped fuel elements grouped together to form a cylindrically shaped core. A gas coolant flows axially through circular channels within the elements, and the fuel is dispersed within the solid element material either as a composite or in the form of coated pellets. Different coolant, fuel, coating, and element materials can be selected to represent different prismatic-core concepts. The computer program allows the user to divide the core into any arbitrary number of axial levels to account for different axial power shapes. An option in the program allows the automatic determination of the core height that results in the maximum specific power. The results of parametric specific power calculations using this program are presented for various reactor concepts.

  9. Dissipation and Rheology of Sheared Soft-Core Frictionless Disks

    E-Print Network [OSTI]

    Daniel Vågberg; Peter Olsson; S. Teitel

    2014-09-17T23:59:59.000Z

    We use numerical simulations to investigate the effect of different dissipative models on the shearing rheology of massive soft-core frictionless disks in two dimensions. We show that the presence of Newtonian (overdamped) vs Bagnoldian (inertial) rheology is related to the formation of large connected clusters of disks, and that sharp transitions may exist between the two as system parameters vary. In the limit of strongly inelastic collisions, we find that rheological curves collapse to a well-defined limit when plotted against an appropriate dimensionless strain rate.

  10. Space variations in axis height of the jet stream core

    E-Print Network [OSTI]

    Leutwyler, Cooke Hearon

    1965-01-01T23:59:59.000Z

    , In addition to the overall in- crease in the number of flights, the advent of jet and turboprop airpla, nes makes the jet stream level, viz. , 25, 000 to 45, 000 ft, the most desirable level for fuel economy during flight. Once man began to move about...SPACE VARIATIONS IN AKIS HEIGHT OF THE JET STREAM CORE A Thesis By COOKE HEARON LEUTWYLER, CAPT USAF Submitted to the Graduate College of the Texas ASM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE...

  11. Simulated ALMA observations of collapsing low-mass dense cores

    E-Print Network [OSTI]

    Levrier, F; Maury, A J; Henning, Th; Launhardt, R; Dullemond, C

    2013-01-01T23:59:59.000Z

    We present a possible identification strategy for first hydrostatic core (FHSC) candidates and make predictions of ALMA dust continuum emission maps from these objects. We analyze the results given by the different bands and array configurations and identify which combinations of the two represent our best chance of solving the fragmentation issue in these objects. If the magnetic field is playing a role, the emission pattern will show evidence of a pseudo-disk and even of a magnetically driven outflow, which pure hydrodynamical calculations cannot reproduce.

  12. A star harbouring a wormhole at its core

    SciTech Connect (OSTI)

    Dzhunushaliev, Vladimir [Institute for Basic Research, Eurasian National University, Astana, 010008 (Kazakhstan); Folomeev, Vladimir [Institute of Physicotechnical Problems and Material Science of the NAS of the Kyrgyz Republic, 265 a, Chui Street, Bishkek, 720071 (Kyrgyzstan); Kleihaus, Burkhard; Kunz, Jutta, E-mail: vdzhunus@krsu.edu.kg, E-mail: vfolomeev@mail.ru, E-mail: kleihaus@theorie.physik.uni-oldenburg.de, E-mail: kunz@theorie.physik.uni-oldenburg.de [Institut für Physik, Universität Oldenburg, Postfach 2503 D-26111 Oldenburg (Germany)

    2011-04-01T23:59:59.000Z

    We consider a configuration consisting of a wormhole filled by a perfect fluid. Such a model can be applied to describe stars as well as neutron stars with a nontrivial topology. The presence of a tunnel allows for motion of the fluid, including oscillations near the core of the system. Choosing the polytropic equation of state for the perfect fluid, we obtain static regular solutions. Based on these solutions, we consider small radial oscillations of the configuration and show that the solutions are stable with respect to linear perturbations in the external region.

  13. Core-Corona Separation in Ultrarelativistic Heavy Ion Collisions

    SciTech Connect (OSTI)

    Werner, Klaus [SUBATECH, University of Nantes-IN2P3/CNRS-EMN, Nantes 44000 (France)

    2007-04-13T23:59:59.000Z

    Simple geometrical considerations show that the collision zone in high energy nuclear collisions may be divided into a central part ('core'), with high energy densities, and a peripheral part ('corona'), with smaller energy densities, more like in pp or pA collisions. We present calculations that allow us to separate these two contributions, and which show that the corona contribution is quite small (but not negligible) for central collisions, but gets increasingly important with decreasing centrality. We will discuss consequences concerning results obtained in heavy ion collisions at the BNL Relativistic Heavy Ion Collider and CERN Super Proton Synchrotron.

  14. EMISSION MEASURE DISTRIBUTION AND HEATING OF TWO ACTIVE REGION CORES

    SciTech Connect (OSTI)

    Tripathi, Durgesh [Inter-University Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411 007 (India); Klimchuk, James A. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Mason, Helen E., E-mail: durgesh@iucaa.ernet.in [Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom)

    2011-10-20T23:59:59.000Z

    Using data from the Extreme-ultraviolet Imaging Spectrometer aboard Hinode, we have studied the coronal plasma in the core of two active regions. Concentrating on the area between opposite polarity moss, we found emission measure distributions having an approximate power-law form EM{proportional_to}T{sup 2.4} from log T = 5.5 up to a peak at log T = 6.55. We show that the observations compare very favorably with a simple model of nanoflare-heated loop strands. They also appear to be consistent with more sophisticated nanoflare models. However, in the absence of additional constraints, steady heating is also a viable explanation.

  15. Bolometric and UV light curves of core-collapse supernovae

    SciTech Connect (OSTI)

    Pritchard, T. A.; Roming, P. W. A. [Department of Astronomy and Astrophysics, Penn State University, 525 Davey Lab, University Park, PA 16802 (United States); Brown, Peter J. [Department of Physics and Astronomy, George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Texas A. and M. University, 4242 TAMU, College Station, TX 77843 (United States); Bayless, Amanda J. [Southwest Research Institute, Department of Space Science, 6220 Culebra Road, San Antonio, TX 78238 (United States); Frey, Lucille H. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2014-06-01T23:59:59.000Z

    The Swift UV-Optical Telescope (UVOT) has been observing core-collapse supernovae (CCSNe) of all subtypes in the UV and optical since 2005. Here we present 50 CCSNe observed with the Swift UVOT, analyzing their UV properties and behavior. Where we have multiple UV detections in all three UV filters (? {sub c} = 1928-2600 Å), we generate early time bolometric light curves, analyze the properties of these light curves and the UV contribution to them, and derive empirical corrections for the UV-flux contribution to optical-IR based bolometric light curves.

  16. Full Core Reactor Analysis: Running Denovo on Jaguar

    SciTech Connect (OSTI)

    Jarrell, Joshua J [ORNL] [ORNL; Godfrey, Andrew T [ORNL] [ORNL; Evans, Thomas M [ORNL] [ORNL; Davidson, Gregory G [ORNL] [ORNL

    2013-01-01T23:59:59.000Z

    Fully-consistent, full-core, 3D, deterministic neutron transport simulations using the orthogonal mesh code Denovo were run on the massively parallel computing architecture Jaguar XT5. Using energy and spatial parallelization schemes, Denovo was able to efficiently scale to more than 160k processors. Cell-homogenized cross sections were used with step-characteristics, linear-discontinuous finite element, and trilinear-discontinuous finite element spatial methods. It was determined that using the finite element methods gave considerably more accurate eigenvalue solutions for large-aspect ratio meshes than using step-characteristics.

  17. System Study: High-Pressure Core Spray 1998–2012

    SciTech Connect (OSTI)

    T. E. Wierman

    2013-10-01T23:59:59.000Z

    This report presents an unreliability evaluation of the high-pressure core spray (HPCS) at 8 U.S. commercial boiling water reactors. Demand, run hours, and failure data from fiscal year 1998 through 2012 for selected components were obtained from the Equipment Performance and Information Exchange (EPIX). The unreliability results are trended for the most recent 10 year period while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the HPCS results.

  18. System Study: Reactor Core Isolation Cooling 1998–2012

    SciTech Connect (OSTI)

    T. E. Wierman

    2013-10-01T23:59:59.000Z

    This report presents an unreliability evaluation of the reactor core isolation cooling (RCIC) system at 31 U.S. commercial boiling water reactors. Demand, run hours, and failure data from fiscal year 1998 through 2012 for selected components were obtained from the Equipment Performance and Information Exchange (EPIX). The unreliability results are trended for the most recent 10 year period while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing trend was identified in the HPCI results. Statistically significant decreasing trends were identified for RCIC start-only and 8-hour trends.

  19. seca-core-tech-sofc-interconnect | netl.doe.gov

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron4 Self-Scrubbing:,, ,Development ofrluyendiNeed for713thProgramCoreSECA

  20. SECURITY CORE FUNCTION AND DEFINITION REPORT | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOrigin ofEnergy at Waste-to-EnergySEAB_Minutes_1_20_11.pdfSEB SecretariatJ-1SECURITY CORE