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Sample records for vortex core deformation

  1. X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation

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

    alloy) revealed a way to easily switch the vortex polarization with a small alternating electrical current, but how the switching actually occurred has remained speculative in...

  2. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Magnetic Vortex Core Reversal by Low-Field Excitations Print Wednesday, 28 March 2007 00:00 In micrometer-sized magnetic thin...

  3. Magnetic Vortex Core Reversal by Low-Field Excitations

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACTThousandReport) |Administration SavannahMagnetic Vortex Core

  4. Magnetic Vortex Core Reversal by Low-Field Excitations

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACTThousandReport) |Administration SavannahMagnetic Vortex CoreMagnetic

  5. Magnetic Vortex Core Reversal by Low-Field Excitations

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACTThousandReport) |Administration SavannahMagneticMagnetic Vortex Core

  6. Impact of vortex core structure on equftion of motion V.A.Budarin

    E-Print Network [OSTI]

    1 Impact of vortex core structure on equftion of motion V.A.Budarin National Polytechnical-solid hollow and continuous vortex core wall has been examined in this paper. Two other exact solutions derived of thick-walled cylinders and task about the tube rotation. Comparison of the results obtained has been

  7. Mineral Deformation at Earth's Core-Mantle Boundary

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

    for its liquid-iron outer core), this convection causes deformation of solid rocks by plastic flow. At the core-mantle boundary (CMB), 2900 km deep, seismologists have discovered...

  8. Mineral Deformation at Earth's Core-Mantle Boundary

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

    Because Earth is mostly solid (except for its liquid-iron outer core), this convection causes deformation of solid rocks by plastic flow. At the core-mantle boundary (CMB), 2900 km...

  9. Mineral Deformation at Earth's Core-Mantle Boundary

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

    Mineral Deformation at Earth's Core-Mantle Boundary Print Earth is a dynamic planet in which convection takes place on the scale of thousands of kilometers. Because Earth is mostly...

  10. Magnetic Vortex Core Reversal by Low-Field Excitations

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACTThousandReport) |Administration SavannahMagnetic Vortex

  11. Magnetic Vortex Core Reversal by Low-Field Excitations

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACTThousandReport) |Administration SavannahMagnetic VortexMagnetic

  12. Deep sub-nanosecond reversal of vortex cores confined in a spin-wave potential well

    SciTech Connect (OSTI)

    Dong, Xinwei; Wang, Zhenyu; Wang, Ruifang, E-mail: wangrf@xmu.edu.cn [Department of Physics and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen 361005 (China)

    2014-03-17

    A spin-wave potential well is created in a permalloy nanodisk by setting up a cylindrical cavity in the center of the sample. We then apply a single-harmonic external magnetic field perpendicular to the disk plane to switch the vortex polarity of the sample. Our micromagnetic numerical studies establish that the effective spin-wave confinement by the potential well leads to much stronger magnetization oscillation in the sample. Therefore, the vortex core can be reversed well below 200 ps and over a wide range of field frequency. Our findings present an additional efficient means for ultrafast switching of magnetic vortices.

  13. Role of the Vortex-Core Energy on the Berezinskii-Kosterlitz-Thouless Transition in Thin Films of NbN

    E-Print Network [OSTI]

    Raychaudhuri, Pratap

    Role of the Vortex-Core Energy on the Berezinskii-Kosterlitz-Thouless Transition in Thin Films-Kosterlitz-Thouless (BKT) transition in thin films of NbN at various film thickness, by probing the effect of vortex played by the vortex-core energy in determining the characteristic signatures of the BKT physics, and we

  14. Ultra-fast magnetic vortex core reversal by a local field pulse

    SciTech Connect (OSTI)

    Rückriem, R.; Albrecht, M., E-mail: manfred.albrecht@physik.uni-augsburg.de [Institute of Physics, Chemnitz University of Technology, 09107 Chemnitz (Germany); Schrefl, T. [St. Pölten University of Applied Science, 3100 St. Pölten (Austria)

    2014-02-03

    Magnetic vortex core reversal of a 20-nm-thick permalloy disk with a diameter of 100?nm was studied by micromagnetic simulations. By applying a global out-of-plane magnetic field pulse, it turned out that the final core polarity is very sensitive to pulse width and amplitude, which makes it hard to control. The reason for this phenomenon is the excitation of radial spin waves, which dominate the reversal process. The excitation of spin waves can be strongly suppressed by applying a local field pulse within a small area at the core center. With this approach, ultra-short reversal times of about 15 ps were achieved, which are ten times faster compared to a global pulse.

  15. Strong vortex core pinning and Barkhausen-free magnetization response in thin Permalloy disks induced by implantation of 1 × 10{sup 4} Ga{sup +} ions

    SciTech Connect (OSTI)

    Fani Sani, F., E-mail: fanisani@ualberta.ca, E-mail: mark.freeman@ualberta.ca; Losby, J. E.; Diao, Z.; Parsons, L. C.; Burgess, J. A. J.; Hiebert, W. K.; Freeman, M. R., E-mail: fanisani@ualberta.ca, E-mail: mark.freeman@ualberta.ca [Department of Physics, University of Alberta, Edmonton, Alberta T6G 2G7 (Canada); National Institute for Nanotechnology (NINT), Edmonton, Alberta T6G 2M9 (Canada); Vick, D. [National Institute for Nanotechnology (NINT), Edmonton, Alberta T6G 2M9 (Canada)

    2014-05-07

    Artificial vortex core pinning sites are induced in thin Permalloy disks by point exposure to as few as 10?000 ions from a focused Ga{sup +} beam. These pinning sites yield a first-order change in the magnetization response of the disk. A single site can keep the vortex core pinned over an applied field range comparable to the vortex annihilation field of the unaltered disk. Several widely separated sites can work together to keep the core pinned in one place, while the Barkhausen effect is eliminated from the magnetization curve over a range approaching the saturation moment of the disk.

  16. Mineral Deformation at Earth's Core-Mantle Boundary

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

    crystals), individual crystals deform preferentially along slip planes. This results in crystal rotations that lead to crystallographic preferred orientation ("texture") in the...

  17. Mineral Deformation at Earth's Core-Mantle Boundary

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

    its interior to the surface via convection. Convection not only manifests itself in the plastic deformation of mineral phases due to stress, but it also drives plate tectonics....

  18. On the evolution of vortex rings with swirl

    SciTech Connect (OSTI)

    Naitoh, Takashi, E-mail: naitoh.takashi@nitech.ac.jp [Department of Engineering Physics, Electronics and Mechanics, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Okura, Nobuyuki, E-mail: ohkura@meijo-u.ac.jp [Department of Vehicle and Mechanical Engineering, Meijo University, 1-501 Shiogamaguchi Tempaku-ku, Nagoya 468-8502 (Japan); Gotoh, Toshiyuki, E-mail: gotoh.toshiyuki@nitech.ac.jp [Department of Scientific and Engineering Simulation, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Kato, Yusuke [Controller Business Unit Engineering Division 1, Engineering Department 3, Denso Wave Incorporated, 1 Yoshiike Kusagi Agui-cho, Chita-gun Aichi 470-2297 (Japan)

    2014-06-15

    A laminar vortex ring with swirl, which has the meridional velocity component inside the vortex core, was experimentally generated by the brief fluid ejection from a rotating outlet. The evolution of the vortex ring was investigated with flow visualizations and particle image velocimetry measurements in order to find the influence of swirling flow in particular upon the transition to turbulence. Immediately after the formation of a vortex ring with swirl, a columnar strong vortex along the symmetric axis is observed in all cases of the present experiment. Then the characteristic fluid discharging from a vortex ring with swirl referred to as “peeling off” appears. The amount of discharging fluid due to the “peeling off” increases with the angular velocity of the rotating outlet. We conjectured that the mechanism generating the “peeling off” is related to the columnar strong vortex by close observations of the spatio-temporal development of the vorticity distribution and the cutting 3D images constructed from the successive cross sections of a vortex ring. While a laminar vortex ring without swirl may develop azimuthal waves around its circumference at some later time and the ring structure subsequently breaks, the swirling flow in a vortex ring core reduces the amplification rate of the azimuthal wavy deformation and preserved its ring structure. Then the traveling distance of a vortex ring can be extended using the swirl flow under certain conditions.

  19. NUMERICAL SIMULATION OF VORTEX BREAKDOWN

    E-Print Network [OSTI]

    Prete, Vincenza Del

    2011-01-01

    axis of the tube and is called the vortex core. The basicthe tube plus a perturbation caused by the vortex breakdown.of the tube. Thus the occurrence of the vortex breakdown

  20. Mineral Deformation at Earth's Core-Mantle Boundary

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

    At the core-mantle boundary (CMB), 2900 km deep, seismologists have discovered that seismic waves travel faster in certain directions. This seismic anisotropy appears to be...

  1. Mineral Deformation at Earth's Core-Mantle Boundary

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines light on77 PAGE OFDetectionBenchmark Performance 111.1Mineral Deformation

  2. Mineral Deformation at Earth's Core-Mantle Boundary

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJessework uses concrete7 Assessment ofLana7,Mimicking theMineral Deformation at

  3. Effect of boundary conditions on axial flow in a concentrated vortex core Richard K. Cohn and Manoochehr M. Koochesfahani

    E-Print Network [OSTI]

    Koochesfahani, Manoochehr M.

    of confined flows such as vortex chambers, and swirl separators (e.g., hydrocyclones). More recently

  4. X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation

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

    represents the binary 0 and the other the binary 1. Driven by the consumer's insatiable demand for inexpensive devices that store more data in a smaller area and access it faster...

  5. X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation

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

    devices that store more data in a smaller area and access it faster while consuming less power, the data storage industry is ever on the lookout for new materials with new...

  6. X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout /Two0PhotosPresentationsWorld's largestX-Ray ImagingImaging

  7. X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout /Two0PhotosPresentationsWorld's largestX-Ray

  8. X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout /Two0PhotosPresentationsWorld's largestX-RayX-Ray Imaging of

  9. X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLos Alamos verifies largest single goldWind PowerX-RayX-Ray

  10. X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLos Alamos verifies largest single goldWind PowerX-RayX-RayX-Ray

  11. X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLos Alamos verifies largest single goldWind PowerX-RayX-RayX-RayX-Ray

  12. X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLos Alamos verifies largest single goldWind

  13. X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLos Alamos verifies largest single goldWindX-Ray Imaging of the Dynamic

  14. Vortex pinning by inhomogeneities in type-II superconductors

    E-Print Network [OSTI]

    Chapman, Jon

    Vortex pinning by inhomogeneities in type-II superconductors S.J. Chapman #3;y G. Richardson zx of a curvilinear vortex in an inhomogeneous type-II superconducting material in the limit as the vortex core radius of the superconducting electrons acts as a pinning potential for the vortex, so that vortices will be attracted

  15. Vortex in a relativistic perfect isentropic fluid and Nambu Goto dynamics

    E-Print Network [OSTI]

    B. Boisseau

    1999-11-26

    By a weak deformation of the cylindrical symmetry of the potential vortex in a relativistic perfect isentropic fluid, we study the possible dynamics of the central line of this vortex. In "stiff" material the Nanbu-Goto equations are obtained

  16. NUMERICAL SIMULATION OF VORTEX BREAKDOWN

    E-Print Network [OSTI]

    Prete, Vincenza Del

    2011-01-01

    irrotational vortex. NRC Con. Aero Rep. LR-378. Hald, O. &vortex breakdown" phenomenon. Aero Dept. , Imperial ColI.

  17. Distinct magnetic signatures of fractional vortex configurations in multiband superconductors

    SciTech Connect (OSTI)

    Silva, R. M. da; Domínguez, D.; Aguiar, J. Albino

    2014-12-08

    Vortices carrying fractions of a flux quantum are predicted to exist in multiband superconductors, where vortex core can split between multiple band-specific components of the superconducting condensate. Using the two-component Ginzburg-Landau model, we examine such vortex configurations in a two-band superconducting slab in parallel magnetic field. The fractional vortices appear due to the band-selective vortex penetration caused by different thresholds for vortex entry within each band-condensate, and stabilize near the edges of the sample. We show that the resulting fractional vortex configurations leave distinct fingerprints in the static measurements of the magnetization, as well as in ac dynamic measurements of the magnetic susceptibility, both of which can be readily used for the detection of these fascinating vortex states in several existing multiband superconductors.

  18. American Institute of Aeronautics and Astronautics An Experimental Study of the Stability of a Four-Vortex

    E-Print Network [OSTI]

    Nelson, Robert C.

    . Helium bubbles were introduced into the core region of individual vortices to visualize these wake. These results suggest that the use of helium bubbles is a suitable method for visualizing wake vortices programs can be divided into two categories, vortex detection and vortex alleviation. The vortex detection

  19. Improved vortex reactor system

    DOE Patents [OSTI]

    Diebold, James P. (Lakewood, CO); Scahill, John W. (Evergreen, CO)

    1995-01-01

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

  20. Vortex diode jet

    DOE Patents [OSTI]

    Houck, Edward D. (Idaho Falls, ID)

    1994-01-01

    A fluid transfer system that combines a vortex diode with a jet ejector to transfer liquid from one tank to a second tank by a gas pressurization method having no moving mechanical parts in the fluid system. The vortex diode is a device that has a high resistance to flow in one direction and a low resistance to flow in the other.

  1. The Holographic Superconductor Vortex

    E-Print Network [OSTI]

    Marc Montull; Alex Pomarol; Pedro J. Silva

    2009-09-02

    A gravity dual of a superconductor at finite temperature has been recently proposed. We present the vortex configuration of this model and study its properties. In particular, we calculate the free energy as a function of an external magnetic field, the magnetization and the superconducting density. We also find the two critical magnetic fields that define the region in which the vortex configurations are energetically favorable.

  2. Improved vortex reactor system

    DOE Patents [OSTI]

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

    1995-05-09

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

  3. A Model of Compressor Blade Row Interaction with Shock Induced Vortex Shedding

    E-Print Network [OSTI]

    Cincinnati, University of

    A Model of Compressor Blade Row Interaction with Shock Induced Vortex Shedding Mark G. Turner". The mid and far spacings represent typical axial gaps found in operational fans and compressors. However behind a stator are modeled. The model is based on a Burger vortex core model for shed vortices

  4. Vortex-Based Aero- and Hydrodynamic Estimation

    E-Print Network [OSTI]

    Hemati, Maziar Sam

    2013-01-01

    Vortex-Based Aero- and Hydrodynamic Estimation . . . . . .2 Aero- andbenefit from vortex-based aero- and hydrodynamic estimation.

  5. Two-dimensional model problem to explain counter-rotating vortex pair formation in a transverse jet

    E-Print Network [OSTI]

    Mahesh, Krishnan

    Two-dimensional model problem to explain counter-rotating vortex pair formation in a transverse jet A two-dimensional model problem is used to study the evolution of the cross section of a transverse jet and the counter-rotating vortex pair CVP . The solution to the model problem shows deformation of the jet similar

  6. Dynamics of a relativistic Rankine vortex for a two-constituent superfluid in a weak perturbation of cylindrical symmetry

    E-Print Network [OSTI]

    B. Boisseau

    1999-01-18

    From a recent study of a stationary cylindrical solution for a relativistic two-constituent superfluid at low temperature limit, we propose to specify this solution under the form of a relativistic generalisation of a Rankine vortex (Potential vortex whose the core has a solid body rotation).Then we establish the dynamics of the central line of this vortex by supposing that the deviation from the cylindrical configuration is weak in the neighbourhood of the core of the vortex. In "stiff" material the Nambu-Goto equations are obtained.

  7. MICROMAGNETIC STUDIES OF THE TRANSITION BETWEEN VORTEX AND SINGLE-DOMAIN STATES IN SUB-100 NM NANODOTS 

    E-Print Network [OSTI]

    King, Andrew

    2012-04-26

    20 40 60 80 100 120 140 To ta l E ne rg y (e V ) Vortex-­?Core Posi2on (nm) Total Energy vs. Vortex-­?Core Posi2on 65 nm Diameter Iron Dot 0 kOe 0.5 kOe 17... B ar ri er (e V ) Applied Field (kOe) Energy Barriers vs. Applied Field 40 nm Diameter Iron Dot Vortex Annihila:on Vortex Nuclea:on 21 FIG. 8. Energy barriers plotted versus applied...

  8. Strings, vortex rings, and modes of instability

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

    Gubser, Steven S.; Nayar, Revant; Parikh, Sarthak

    2015-03-01

    We treat string propagation and interaction in the presence of a background Neveu–Schwarz three-form field strength, suitable for describing vortex rings in a superfluid or low-viscosity normal fluid. A circular vortex ring exhibits instabilities which have been recognized for many years, but whose precise boundaries we determine for the first time analytically in the small core limit. Two circular vortices colliding head-on exhibit stronger instabilities which cause splitting into many small vortices at late times. We provide an approximate analytic treatment of these instabilities and show that the most unstable wavelength is parametrically larger than a dynamically generated length scalemore »which in many hydrodynamic systems is close to the cutoff. We also summarize how the string construction we discuss can be derived from the Gross–Pitaevskii Lagrangian, and also how it compares to the action for giant gravitons.« less

  9. Super Stability of Laminar Vortex Flow in Superfluid 3He-B

    E-Print Network [OSTI]

    V. B. Eltsov; R. de Graaf; P. J. Heikkinen; J. J. Hosio; R. Hanninen; M. Krusius; V. S. L'vov

    2010-05-04

    Vortex flow remains laminar up to large Reynolds numbers (Re~1000) in a cylinder filled with 3He-B. This is inferred from NMR measurements and numerical vortex filament calculations where we study the spin up and spin down responses of the superfluid component, after a sudden change in rotation velocity. In normal fluids and in superfluid 4He these responses are turbulent. In 3He-B the vortex core radius is much larger which reduces both surface pinning and vortex reconnections, the phenomena, which enhance vortex bending and the creation of turbulent tangles. Thus the origin for the greater stability of vortex flow in 3He-B is a quantum phenomenon. Only large flow perturbations are found to make the responses turbulent, such as the walls of a cubic container or the presence of invasive measuring probes inside the container.

  10. The internal structure of a vortex in a two-dimensional superfluid with long healing length and its implications

    SciTech Connect (OSTI)

    Klein, Avraham; Aleiner, Igor L.; Agam, Oded

    2014-07-15

    We analyze the motion of quantum vortices in a two-dimensional spinless superfluid within Popov’s hydrodynamic description. In the long healing length limit (where a large number of particles are inside the vortex core) the superfluid dynamics is determined by saddle points of Popov’s action, which, in particular, allows for weak solutions of the Gross–Pitaevskii equation. We solve the resulting equations of motion for a vortex moving with respect to the superfluid and find the reconstruction of the vortex core to be a non-analytic function of the force applied on the vortex. This response produces an anomalously large dipole moment of the vortex and, as a result, the spectrum associated with the vortex motion exhibits narrow resonances lying within the phonon part of the spectrum, contrary to traditional view.

  11. Vortex-Based Aero- and Hydrodynamic Estimation

    E-Print Network [OSTI]

    Hemati, Maziar Sam

    2013-01-01

    1. The strength of a vortex tube is uniform along the tube.3. The strength of a vortex tube is invariant in time. Theof Vortex Ring Formation at the Edge of a Circular Tube. ”

  12. GREEN'S FUNCTIONS OF VORTEX OPERATORS

    E-Print Network [OSTI]

    Polchinski, Joseph

    2013-01-01

    8 g Olesen vortex • , somewhere in space. The tube between cvortex operators have surface clustering, as this implies that magnetic flux is forming into tubes.

  13. Modification of vortex dynamics and transport properties of transitional axisymmetric jets using zero-net-mass-flux actuation

    SciTech Connect (OSTI)

    Önder, Asim; Meyers, Johan

    2014-07-15

    We study the near field of a zero-net-mass-flux (ZNMF) actuated round jet using direct numerical simulations. The Reynolds number of the jet Re{sub D} = 2000 and three ZNMF actuators are used, evenly distributed over a circle, and directed towards the main jet. The actuators are triggered in phase, and have a relatively low momentum coefficient of C{sub ?} = 0.0049 each. We study four different control frequencies with Strouhal numbers ranging from St{sub D} = 0.165 to St{sub D} = 1.32; next to that, also two uncontrolled baseline cases are included in the study. We find that this type of ZNMF actuation leads to strong deformations of the near-field jet region that are very similar to those observed for non-circular jets. At the end of the jet's potential core (x/D = 5), the jet-column cross section is deformed into a hexagram-like geometry that results from strong modifications of the vortex structures. Two mechanisms lead to these modifications, i.e., (i) self-deformation of the jet's primary vortex rings started by distortions in their azimuthal curvature by the actuation, and (ii) production of side jets by the development and subsequent detachment of secondary streamwise vortex pairs. Further downstream (x/D = 10), the jet transforms into a triangular pattern, as the sharp corner regions of the hexagram entrain fluid and spread. We further investigate the global characteristics of the actuated jets. In particular when using the jet preferred frequency, i.e., St{sub D} = 0.33, parameters such as entrainment, centerline decay rate, and mean turbulent kinetic energy are significantly increased. Furthermore, high frequency actuation, i.e., St{sub D} = 1.32, is found to suppress the mechanisms leading to large scale structure growth and turbulent kinetic energy production. The simulations further include a passive scalar equation, and passive scalar mixing is also quantified and visualized.

  14. Motion of a helical vortex

    E-Print Network [OSTI]

    Fuentes, Oscar Velasco

    2015-01-01

    We study the motion of a single helical vortex in an unbounded, inviscid, incompressible fluid. The vortex is an infinite tube whose centerline is a helix and whose cross section is a circle of small radius (compared to the radius of curvature) where the vorticity is uniform and parallel to the centerline. Ever since Joukowsky (1912) deduced that this vortex translates and rotates steadily without change of form, numerous attempts have been made to compute these self-induced velocities. Here we use Hardin's (1982) solution for the velocity field to find new expressions for the vortex's linear and angular velocities. Our results, verified by numerically computing the Helmholtz integral and the Rosenhead-Moore approximation to the Biot-Savart law, are more accurate than previous results over the whole range of values of the vortex pitch and cross-section. We then use the new formulas to study the advection of passive particles near the vortex; we find that the vortex's motion and capacity to transport fluid dep...

  15. Vortex Ring Interaction with a Particle Layer: Implications for Sediment Transport

    E-Print Network [OSTI]

    Dalziel, Stuart

    resuspension has been studied much less. This is an important mechanism, however, as it represents an integral conducted to study particle resuspension by vortex rings colliding with a particle bed. The dynamics at the resuspension onset are investigated, showing that the deformable particle bed resembles a free slip boundary

  16. Elementary Vortex Processes in Thermal Superfluid Turbulence

    E-Print Network [OSTI]

    Kivotides, Demosthenes; Wilkin, S. Louise

    2009-01-01

    a complex system of vortex tubes has only (a vigorouslyIn this context, the vortex tube model (VTM) of Kivotidesstraight normal ?uid vortex tube, suggested an explicit

  17. Gravity waves from vortex dipoles and jets 

    E-Print Network [OSTI]

    Wang, Shuguang

    2009-05-15

    The dissertation first investigates gravity wave generation and propagation from jets within idealized vortex dipoles using a nonhydrostatic mesoscale model. Several initially balanced and localized jets induced by vortex dipoles are examined here...

  18. Permeability Evolution during Deformation of Siliciclastic Sandstones

    E-Print Network [OSTI]

    Permeability Evolution during Deformation of Siliciclastic Sandstones from Moab, Utah O. Kwon1 Core; 0.33-ft)- diameter cores of four sandstones from the Moab area to investigate the effect of total. Sandstones with low bulk porosities (Dewey Bridge and Slickrock Subkha) exhibited an increase in permeability

  19. arXiv:nlin.SI/0612065v129Dec2006 FINITE-GAP SOLUTIONS OF THE VORTEX FILAMENT EQUATION

    E-Print Network [OSTI]

    Calini, Annalisa

    arXiv:nlin.SI/0612065v129Dec2006 FINITE-GAP SOLUTIONS OF THE VORTEX FILAMENT EQUATION: ISOPERIODIC filament equation in a neighborhood of multiply covered circles. We construct these solutions by means that matches the deformation data with the knot type of the resulting filament. 1. Introduction In this sequel

  20. VORTEX CREEP AGAINST TOROIDAL FLUX LINES, CRUSTAL ENTRAINMENT, AND PULSAR GLITCHES

    SciTech Connect (OSTI)

    Gügercino?lu, Erbil; Alpar, M. Ali E-mail: alpar@sabanciuniv.edu

    2014-06-10

    A region of toroidally oriented quantized flux lines must exist in the proton superconductor in the core of the neutron star. This region will be a site of vortex pinning and creep. Entrainment of the neutron superfluid with the crustal lattice leads to a requirement of superfluid moment of inertia associated with vortex creep in excess of the available crustal moment of inertia. This will bring about constraints on the equation of state. The toroidal flux region provides the moment of inertia necessary to complement the crust superfluid with postglitch relaxation behavior fitting the observations.

  1. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    switching mechanism, which can be understood within the framework of micromagnetic theory, gives insights into basic magnetization dynamics and their possible application to...

  2. Electroelastic fields in artificially created vortex cores in...

    Office of Scientific and Technical Information (OSTI)

    37831, USA Institute for Problems of Materials Science, National Academy of Science of Ukraine, Kiev, Ukraine Publication Date: 2015-08-03 OSTI Identifier: 1229566 GrantContract...

  3. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    these structures are highly stable, very strong magnetic fields of around half a tesla (approximately one-third the field of the strongest permanent magnet) were previously...

  4. Vortex Cores of Inertial Particles Tobias Gunther and Holger Theisel

    E-Print Network [OSTI]

    coal combustion. In this paper, we present two strategies for the extraction of the corelines and industrial applications, such as combustion of pulverized coal, sediment transport, helicopter brownout, sand blasting, particu- late pollution control, soiling of cars and many more [24, 27, 20]. In contrast

  5. Electroelastic fields in artificially created vortex cores in epitaxial

    Office of Scientific and Technical Information (OSTI)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing(Journal Article) | SciTech(Journal Article) |ContinuumPhotoactive Biological

  6. Magnetic Vortex Core Reversal by Low-Field Excitations

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJesse BergkampCentermillion toMSDS on the internet TheLaboratory

  7. Magnetic Vortex Core Reversal by Low-Field Excitations

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJesse BergkampCentermillion toMSDS on the internet TheLaboratoryMagnetic

  8. Magnetic Vortex Core Reversal by Low-Field Excitations

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACTThousandReport) |Administration SavannahMagnetic

  9. Localized Induction Equation for Stretched Vortex Filament

    E-Print Network [OSTI]

    Kimiaki Konno; Hiroshi Kakuhata

    2006-03-02

    We study numerically the motion of the stretched vortex filaments by using the localized induction equation with the stretch and that without the stretch.

  10. Light propagation around a relativistic vortex flow of dielectric medium

    E-Print Network [OSTI]

    B. Linet

    2000-11-06

    We determine the path of the light around a dielectric vortex described by the relativistic vortex flow of a perfect fluid.

  11. Vortex Hydro Energy Develops Transformational Technology to Harness...

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

    Vortex Hydro Energy Develops Transformational Technology to Harness Energy from Water Currents Vortex Hydro Energy Develops Transformational Technology to Harness Energy from Water...

  12. The idea of vortex energy

    E-Print Network [OSTI]

    V. E. Shapiro

    2011-09-22

    This work formulates and gives grounds for general principles and theorems that question the energy function doctrine and its quantum version as a genuine law of nature without borders of adequacy. The emphasis is on the domain where the energy of systems is conserved -- I argue that only in its tiny part the energy is in the kinetic, potential and thermal forms describable by a generalized thermodynamic potential, whereas otherwise the conserved energy constitutes a whole linked to vortex forces, and can be a factor of things like persistent currents and dark matter.

  13. Vortex Tubes of Turbulent Solar Convection

    E-Print Network [OSTI]

    Kitiashvili, I N; Mansour, N N; Lele, S K; Wray, A A

    2011-01-01

    Investigation of turbulent properties of solar convection is extremely important for understanding of the multi-scale dynamics observed on the solar surface. In particular, recent high-resolution observations revealed ubiquitous vortical structures, and numerical simulations demonstrated links between the vortex tube dynamics and magnetic field organization, and also importance of vortex tube interactions in the mechanism of acoustic wave excitation on the Sun. In this paper we investigate mechanisms of formation of vortex tubes in highly-turbulent convective flows near the solar surface by using realistic radiative hydrodynamic LES simulations. Analysis of data, obtained by the simulations, indicates two basic processes of the vortex tube formation: 1) development of small-scale convective instability inside convective granules, and 2) a Kelvin-Helmholtz type instability of shearing flows in intergranular lanes. Our analysis shows that vortex stretching during these processes is a primary source of generatio...

  14. EXISTENCE OF KNOTTED VORTEX TUBES IN STEADY EULER FLOWS

    E-Print Network [OSTI]

    Enciso, Alberto

    EXISTENCE OF KNOTTED VORTEX TUBES IN STEADY EULER FLOWS ALBERTO ENCISO AND DANIEL PERALTA-SALAS Abstract. We prove the existence of knotted and linked thin vortex tubes for steady solutions of vortex tubes of a Beltrami field that tends to zero at infinity. The structure of the vortex lines

  15. Under consideration for publication in J. Fluid Mech. 1 Some steady axisymmetric vortex ows past

    E-Print Network [OSTI]

    Fornberg, Bengt

    include vortex rings, bounded vortices attached to the sphere and in nite vortex tubes. Four families to be considered: vortex rings, bounded vortices attached to the sphere, and vortex tubes" extending to in nity. Fornberg and K. Miller = 0: attached vortex vortex ring > 0: vortex tube Figure 1. Examples

  16. Vortex Lattices and Crystalline Geometries

    E-Print Network [OSTI]

    Ning Bao; Sarah Harrison; Shamit Kachru; Subir Sachdev

    2013-04-16

    We consider $AdS_2 \\times R^2$ solutions supported by a magnetic field, such as those which arise in the near-horizon limit of magnetically charged $AdS_4$ Reissner-Nordstrom black branes. In the presence of an electrically charged scalar field, such magnetic solutions can be unstable to spontaneous formation of a vortex lattice. We solve the coupled partial differential equations which govern the charged scalar, gauge field, and metric degrees of freedom to lowest non-trivial order in an expansion around the critical point, and discuss the corrections to the free energy and thermodynamic functions arising from the formation of the lattice. We describe how such solutions can also be interpreted, via S-duality, as characterizing infrared crystalline phases of conformal field theories doped by a chemical potential, but in zero magnetic field; the doped conformal field theories are dual to geometries that exhibit dynamical scaling and hyperscaling violation.

  17. Airfoil Vortex Induced Vibration suppression devices

    E-Print Network [OSTI]

    Lee, Evan J. (Evan Joseph)

    2007-01-01

    Vortex Induced Vibrations (VIV) is a major concern of the offshore oil industry. This problem leads to fatigue failure in the marine risers and causes costly replacement of the risers. Appendages such as helical strakes ...

  18. Halos in a deformed relativistic Hartree-Bogoliubov theory in continuum

    SciTech Connect (OSTI)

    Li Lulu; Meng Jie; Ring, P.; Zhao Enguang; Zhou Shangui

    2012-10-20

    In this contribution we present some recent results about neutron halos in deformed nuclei. A deformed relativistic Hartree-Bogoliubov theory in continuumhas been developed and the halo phenomenon in deformed weakly bound nuclei is investigated. These weakly bound quantum systems present interesting examples for the study of the interdependence between the deformation of the core and the particles in the halo. Magnesium and neon isotopes are studied and detailed results are presented for the deformed neutron-rich and weakly bound nuclei {sup 42}Mg. The core of this nucleus is prolate, but the halo has a slightly oblate shape. This indicates a decoupling of the halo orbitals from the deformation of the core. The generic conditions for the existence of halos in deformed nuclei and for the occurrence of this decoupling effect are discussed.

  19. Topological analysis of paraxially scattered electron vortex beams

    E-Print Network [OSTI]

    Axel Lubk; Laura Clark; Giulio Guzzinati; Jo Verbeeck

    2014-10-10

    We investigate topological aspects of sub-nm electron vortex beams upon elastic propagation through atomic scattering potentials. Two main aspects can be distinguished: (i) Significantly reduced delocalization compared to a similar non-vortex beam if the beam centers on an atomic column and (ii) site symmetry dependent splitting of higher-order vortex beams. Furthermore, the results provide insight into the complex vortex line fabric within the elastically scattered wave containing characteristic vortex loops predominantly attached to atomic columns and characteristic twists of vortex lines around atomic columns.

  20. Low NOx Advanced Vortex Combustor

    SciTech Connect (OSTI)

    Edmonds, R.G. (Ramgen Power Systems, Inc., Bellevue, WA); Williams, J.T. (Ramgen Power Systems, Inc., Bellevue, WA); Steele, R.C. (EPRI); Straub, D.L.; Casleton, K.H.; Bining, Avtar (California Energy Commission, Sacramento, CA)

    2008-05-01

    A lean-premixed advanced vortex combustor (AVC) has been developed and tested. The natural gas fueled AVC was tested at the U.S. Department of Energy’s National Energy Technology Laboratory in Morgantown, WV. All testing was performed at elevated pressures and inlet temperatures and at lean fuel-air ratios representative of industrial gas turbines. The improved AVC design exhibited simultaneous NOx /CO/unburned hydrocarbon (UHC) emissions of 4/4/0 ppmv (all emissions corrected to 15% O2 dry). The design also achieved less than 3 ppmv NOx with combustion efficiencies in excess of 99.5%. The design demonstrated marked acoustic dynamic stability over a wide range of operating conditions, which potentially makes this approach significantly more attractive than other lean-premixed combustion approaches. In addition, the measured 1.75% pressure drop is significantly lower than conventional gas turbine combustors, which could translate into an overall gas turbine cycle efficiency improvement. The relatively high velocities and low pressure drop achievable with this technology make the AVC approach an attractive alternative for syngas fuel applications.

  1. Core Topography

    E-Print Network [OSTI]

    Carter-Thompson, Safiya

    2011-04-20

    Core Topography By Safiya Carter-Thompson Submitted to the graduate degree program in Design and the Graduate Faculty of the University of Kansas in partial fulfillment of the requirements for the degree of Master of Arts...-Thompson certifies that this is the approved version of the following thesis: Core Topography ________________________________ Chairperson Mary Anne Jordan Date approved: April 20 th 2011 iii...

  2. 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

    2006-07-08

    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.

  3. Geometric phases for corotating elliptical vortex patches B. N. Shashikantha)

    E-Print Network [OSTI]

    Shashikanth, Banavara N.

    of an infinitely long rectilinear vortex tube of area A whose vorticity distribution is invariant along the lengthGeometric phases for corotating elliptical vortex patches B. N. Shashikantha) Control and Dynamical September 2000 We describe a geometric phase that arises when two elliptical vortex patches co- rotate

  4. Quasi-two Dimensional Hydrodynamics and Interaction of Vortex Tubes

    E-Print Network [OSTI]

    Zakharov, Vladimir

    Quasi-two Dimensional Hydrodynamics and Interaction of Vortex Tubes Vladimir Zakharov 1 but a careful study of the dynamics of the vortex tubes or their systems in a real 3-dimentional nonstationary for description of this type of flow looks very timely. Another motivation is the vortex dynamics

  5. Rogue Waves on a Vortex Filament St Anne's College

    E-Print Network [OSTI]

    Tarrès, Pierre

    Rogue Waves on a Vortex Filament Rehan Shah St Anne's College University of Oxford A dissertation;Abstract The presence of a standing soliton on a vortex filament has been demonstrated theoretically of the local induction approximation (LIA) governing the motion of a thin vortex filament to those of nonlinear

  6. Inelastic electron-vortex-beam scattering

    E-Print Network [OSTI]

    Ruben Van Boxem; Bart Partoens; Jo Verbeeck

    2015-03-16

    Recent theoretical and experimental developments in the field of electron vortex beam physics have raised questions on what exactly this novelty in the field of electron microscopy (and other fields, such as particle physics) really provides. An important part in the answer to those questions lies in scattering theory. The present investigation explores various aspects of inelastic quantum scattering theory for cylindrically symmetric beams with orbital angular momentum. The model system of Coulomb scattering on a hydrogen atom provides the setting to address various open questions: How is momentum transferred? Do vortex beams selectively excite atoms, and how can one employ vortex beams to detect magnetic transitions? The analytical approach presented here provides answers to these questions. OAM transfer is possible, but not through selective excitation; rather, by pre- and post-selection one can filter out the relevant contributions to a specific signal.

  7. Chiral specific electron vortex beam spectroscopy

    E-Print Network [OSTI]

    J. Yuan; S. M. Lloyd; M. Babiker

    2013-07-29

    Electron vortex beams carry well-defined orbital angular momentum (OAM) about the propagation axis. Such beams are thus characterised by chirality features which make them potentially useful as probes of magnetic and other chiral materials. An analysis of the inelastic processes in which electron vortex beams interact with atoms and which involve OAM exchange is outlined, leading to the multipolar selection rules governing this chiral specific electron vortex beam spectroscopy. Our results show clearly that the selection rules are dependent on the dynamical state and location of the atoms involved. In the most favorable scenario, this form of electron spectroscopy can induce magnetic sublevel transitions which are commonly probed using circularly polarized photon beams.

  8. Optical vortex array in spatially varying lattice

    E-Print Network [OSTI]

    Kapoor, Amit; Senthilkumaran, P; Joseph, Joby

    2015-01-01

    We present an experimental method based on a modified multiple beam interference approach to generate an optical vortex array arranged in a spatially varying lattice. This method involves two steps which are: numerical synthesis of a consistent phase mask by using two-dimensional integrated phase gradient calculations and experimental implementation of produced phase mask by utilizing a phase only spatial light modulator in an optical 4f Fourier filtering setup. This method enables an independent variation of the orientation and period of the vortex lattice. As working examples, we provide the experimental demonstration of various spatially variant optical vortex lattices. We further confirm the existence of optical vortices by formation of fork fringes. Such lattices may find applications in size dependent trapping, sorting, manipulation and photonic crystals.

  9. Convectively driven vortex flows in the Sun

    E-Print Network [OSTI]

    J. A. Bonet; I. Marquez; J. Sanchez Almeida; I. Cabello; V. Domingo

    2008-09-23

    We have discovered small whirlpools in the Sun, with a size similar to the terrestrial hurricanes (<~0.5 Mm). The theory of solar convection predicts them, but they had remained elusive so far. The vortex flows are created at the downdrafts where the plasma returns to the solar interior after cooling down, and we detect them because some magnetic bright points (BPs) follow a logarithmic spiral in their way to be engulfed by a downdraft. Our disk center observations show 0.009 vortexes per Mm^2, with a lifetime of the order of 5 min, and with no preferred sense of rotation. They are not evenly spread out over the surface, but they seem to trace the supergranulation and the mesogranulation. These observed properties are strongly biased by our type of measurement, unable to detect vortexes except when they are engulfing magnetic BPs.

  10. Crystalline Geometries from Fermionic Vortex Lattice

    E-Print Network [OSTI]

    M. Reza Mohammadi Mozaffar; Ali Mollabashi

    2013-08-08

    We study charged Dirac fermions on an AdS$_2\\times R^2$ background with a non-zero magnetic field. Under certain boundary conditions, we show that the charged fermion can make the background unstable, resulting in spontaneously formation of a vortex lattice. We observe that an electric field emerges in the back-reacted solution due to the vortex lattice constructed from spin polarized fermions. This electric field may be extended to the UV boundary which leads to a finite charge density. We also discuss corrections to the thermodynamic functions due to the lattice formation.

  11. Neutron Scattering Studies of Vortex Matter in Type-II Superconductors

    SciTech Connect (OSTI)

    Xinsheng Ling

    2012-02-02

    The proposed program is an experimental study of the fundamental properties of Abrikosov vortex matter in type-II superconductors. Most superconducting materials used in applications such as MRI are type II and their transport properties are determined by the interplay between random pinning, interaction and thermal fluctuation effects in the vortex state. Given the technological importance of these materials, a fundamental understanding of the vortex matter is necessary. The vortex lines in type-II superconductors also form a useful model system for fundamental studies of a number of important issues in condensed matter physics, such as the presence of a symmetry-breaking phase transition in the presence of random pinning. Recent advances in neutron scattering facilities such as the major upgrade of the NIST cold source and the Spallation Neutron Source are providing unprecedented opportunities in addressing some of the longstanding issues in vortex physics. The core component of the proposed program is to use small angle neutron scattering and Bitter decoration experiments to provide the most stringent test of the Bragg glass theory by measuring the structure factor in both the real and reciprocal spaces. The proposed experiments include a neutron reflectometry experiment to measure the precise Q-dependence of the structure factor of the vortex lattice in the Bragg glass state. A second set of SANS experiments will be on a shear-strained Nb single crystal for testing a recently proposed theory of the stability of Bragg glass. The objective is to artificially create a set of parallel grain boundaries into a Nb single crystal and use SANS to measure the vortex matter diffraction pattern as a function of the changing angle between the applied magnetic field to the grain boundaries. The intrinsic merits of the proposed work are a new fundamental understanding of type-II superconductors on which superconducting technology is based, and a firm understanding of phases and phase transitions in condensed matter systems with random pinning. The broader impact of the program includes the training of future generation of neutron scientists, and further development of neutron scattering and complementary techniques for studies of superconducting materials. The graduate and undergraduate students participating in this project will learn the state-of-the-art neutron scattering techniques, acquire a wide range of materials research experiences, and participate in the frontier research of superconductivity. This should best prepare the students for future careers in academia, industry, or government.

  12. Existence of knotted vortex tubes in steady Euler flows

    E-Print Network [OSTI]

    Alberto Enciso; Daniel Peralta-Salas

    2014-10-23

    We prove the existence of knotted and linked thin vortex tubes for steady solutions to the incompressible Euler equation in R^3. More precisely, given a finite collection of (possibly linked and knotted) disjoint thin tubes in R^3, we show that they can be transformed with a C^m-small diffeomorphism into a set of vortex tubes of a Beltrami field that tends to zero at infinity. The structure of the vortex lines in the tubes is extremely rich, presenting a positive-measure set of invariant tori and infinitely many periodic vortex lines. The problem of the existence of steady knotted vortex tubes can be traced back to Lord Kelvin.

  13. Vortex generation in protoplanetary disks with an embedded giant planet

    E-Print Network [OSTI]

    M. de Val-Borro; P. Artymowicz; G. D'Angelo; A. Peplinski

    2007-06-21

    Vortices in protoplanetary disks can capture solid particles and form planetary cores within shorter timescales than those involved in the standard core-accretion model. We investigate vortex generation in thin unmagnetized protoplanetary disks with an embedded giant planet with planet to star mass ratio $10^{-4}$ and $10^{-3}$. Two-dimensional hydrodynamical simulations of a protoplanetary disk with a planet are performed using two different numerical methods. The results of the non-linear simulations are compared with a time-resolved modal analysis of the azimuthally averaged surface density profiles using linear perturbation theory. Finite-difference methods implemented in polar coordinates generate vortices moving along the gap created by Neptune-mass to Jupiter-mass planets. The modal analysis shows that unstable modes are generated with growth rate of order $0.3 \\Omega_K$ for azimuthal numbers m=4,5,6, where $\\Omega_K$ is the local Keplerian frequency. Shock-capturing Cartesian-grid codes do not generate very much vorticity around a giant planet in a standard protoplanetary disk. Modal calculations confirm that the obtained radial profiles of density are less susceptible to the growth of linear modes on timescales of several hundreds of orbital periods. Navier-Stokes viscosity of the order $\

  14. Coreless vortex formation in a spinor Bose-Einstein condensate Topological defects vary between superfluid systems described by scalar and vector

    E-Print Network [OSTI]

    Coreless vortex formation in a spinor Bose-Einstein condensate Topological defects vary between-polarized condensates, line defects such as vortices have cores where the density of condensed particles is necessarily zero to keep the order parameter single-valued. However, in condensates with an internal, spin degree

  15. Vortex dynamics in 4 Banavara N. Shashikanth

    E-Print Network [OSTI]

    Shashikanth, Banavara N.

    of oblique vortex shedding behind a heated circular cylinder in laminar wake regime Phys. Fluids 24, 011701 dynamics of Euler's equations for a constant density fluid flow in R4 is studied. Most of the paper focuses of such work are in Refs. 31, 24, 12, 14, and 11. It is fair to say that, in general, classical fluid flows

  16. Quenching Processes in Flame-Vortex Interactions

    E-Print Network [OSTI]

    Zingale, Michael

    for Astrophysical Thermonuclear Flashes 1 , Chicago, IL 60637 y Department of Astronomy and Astrophysics, University-vortex interactions in order to understand quenching of thermonuclear ames. The key question is|can a ther- monuclear. If a ame encounters a 1) The Center for Astrophysical Thermonuclear Flashes is supported by the Department

  17. Gas core nuclear rocket feasibility project

    SciTech Connect (OSTI)

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

    1997-09-01

    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.

  18. ?-deformation and quantization

    E-Print Network [OSTI]

    Junya Yagi

    2014-08-30

    We formulate a deformation of Rozansky-Witten theory analogous to the $\\Omega$-deformation. It is applicable when the target space $X$ is hyperk\\"ahler and the spacetime is of the form $\\mathbb{R} \\times \\Sigma$, with $\\Sigma$ being a Riemann surface. In the case that $\\Sigma$ is a disk, the $\\Omega$-deformed Rozansky-Witten theory quantizes a symplectic submanifold of $X$, thereby providing a new perspective on quantization. As applications, we elucidate two phenomena in four-dimensional gauge theory from this point of view. One is a correspondence between the $\\Omega$-deformation and quantization of integrable systems. The other concerns supersymmetric loop operators and quantization of the algebra of holomorphic functions on a hyperk\\"ahler manifold.

  19. Arm Weakness and Deformity

    E-Print Network [OSTI]

    Galer, Meghan; Heiner, Jason

    2014-01-01

    Figure. Appearance of the patient’s affected right arm andnormal left arm. Volume XV, NO . 4 : July 2014 WesternI n E mergency M edicine Arm Weakness and Deformity Meghan

  20. Origin and dynamics of vortex rings in drop splashing

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

    Lee, Ji San; Park, Su Ji; Lee, Jun Ho; Weon, Byung Mook; Fezzaa, Kamel; Je, Jung Ho

    2015-09-04

    A vortex is a flow phenomenon that is very commonly observed in nature. More than a century, a vortex ring that forms during drop splashing has caught the attention of many scientists due to its importance in understanding fluid mixing and mass transport processes. However, the origin of the vortices and their dynamics remain unclear, mostly due to the lack of appropriate visualization methods. Here, with ultrafast X-ray phase-contrast imaging, we show that the formation of vortex rings originates from the energy transfer by capillary waves generated at the moment of the drop impact. Interestingly, we find a row ofmore »vortex rings along the drop wall, as demonstrated by a phase diagram established here, with different power-law dependencies of the angular velocities on the Reynolds number. These results provide important insight that allows understanding and modelling any type of vortex rings in nature, beyond just vortex rings during drop splashing.« less

  1. Vortex Bubble Formation in Pair Plasmas

    E-Print Network [OSTI]

    Berezhiani, V I; Mahajan, S M; Aleksi?, B N

    2013-01-01

    It is shown that delocalized vortex solitons in relativistic pair plasmas with small temperature asymmetries can be unstable for intermediate intensities of the background electromagnetic field. Instability leads to the generation of ever-expanding cavitating bubbles in which the electromagnetic fields are zero. The existence of such electromagnetic bubbles is demonstrated by qualitative arguments based on a hydrodynamic analogy, and by numerical solutions of the appropriate Nonlinear Schr\\"odinger equation with a saturating nonlinearity.

  2. Liquid Vortex Shielding for Fusion Energy Applications

    SciTech Connect (OSTI)

    Bardet, Philippe M. [University of California, Berkeley (United States); Supiot, Boris F. [University of California, Berkeley (United States); Peterson, Per F. [University of California, Berkeley (United States); Savas, Oemer [University of California, Berkeley (United States)

    2005-05-15

    Swirling liquid vortices can be used in fusion chambers to protect their first walls and critical elements from the harmful conditions resulting from fusion reactions. The beam tube structures in heavy ion fusion (HIF) must be shielded from high energy particles, such as neutrons, x-rays and vaporized coolant, that will cause damage. Here an annular wall jet, or vortex tube, is proposed for shielding and is generated by injecting liquid tangent to the inner surface of the tube both azimuthally and axially. Its effectiveness is closely related to the vortex tube flow properties. 3-D particle image velocimetry (PIV) is being conducted to precisely characterize its turbulent structure. The concept of annular vortex flow can be extended to a larger scale to serve as a liquid blanket for other inertial fusion and even magnetic fusion systems. For this purpose a periodic arrangement of injection and suction holes around the chamber circumference are used, generating the layer. Because it is important to match the index of refraction of the fluid with the tube material for optical measurement like PIV, a low viscosity mineral oil was identified and used that can also be employed to do scaled experiments of molten salts at high temperature.

  3. Electron vortex orbits and merger T. B. Mitchella)

    E-Print Network [OSTI]

    California at San Diego, University of

    of the spatially extended vortices are calculated by the point vortex approximation, and simple rules are used resulted in predictions for tim

  4. Coseismic sediment deformation during the 1989 Loma Prieta Ronaldo I. Borja1

    E-Print Network [OSTI]

    Borja, Ronaldo I.

    Coseismic sediment deformation during the 1989 Loma Prieta earthquake Ronaldo I. Borja1 and Wai. [1] Inelastic horizontal sediment deformation from the MS 7.1, 17 October 1989 Loma Prieta earthquake data and sediment properties measured from in situ seismic tests and laboratory tests on cored sediment

  5. Dual vortex theory of strongly interacting electrons: A non-Fermi...

    Office of Scientific and Technical Information (OSTI)

    Dual vortex theory of strongly interacting electrons: A non-Fermi liquid with a twist Citation Details In-Document Search Title: Dual vortex theory of strongly interacting...

  6. Deformed Noncommutative Tori

    E-Print Network [OSTI]

    Joakim Arnlind; Harald Grosse

    2012-01-13

    We recall a construction of non-commutative algebras related to a one-parameter family of (deformed) spheres and tori, and show that in the case of tori, the *-algebras can be completed into C*-algebras isomorphic to the standard non-commutative torus. As the former was constructed in the context of matrix (or fuzzy) geometries, it provides an important link to the framework of non-commutative geometry, and opens up for a concrete way to study deformations of non-commutative tori. Furthermore, we show how the well-known fuzzy sphere and fuzzy torus can be obtained as formal scaling limits of finite-dimensional representations of the deformed algebras, and their projective modules are described together with connections of constant curvature.

  7. Almost Optimal Convergence of the Point Vortex Method for Vortex Sheets using Numerical Filtering

    E-Print Network [OSTI]

    Ferguson, Thomas S.

    vortices, numerical filtering, discrete Cauchy­Kowalewski theorem. AMS subject classifications: primary 65M subsequent modes will be dominated by roundoff error. Since these highest modes are amplified the fastest, singularity formation appears to be generic, even for vortex sheets initially near equilibrium [13, 6, 19

  8. Mineral Deformation at Earth's Core-Mantle Boundary

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

    Rocks Flow in the Deep Earth Earth is remarkably plastic. Our planet is slowly cooling as heat is transferred from its interior to the surface via convection. Convection not only...

  9. Mineral Deformation at Earth's Core-Mantle Boundary

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

    In the lower mantle, this magnesium silicate has a crystal structure known as "perovskite." However, at the lowermost mantle, the MgSiO3 is compressed into a new phase known...

  10. Mineral Deformation at Earth's Core-Mantle Boundary

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines light on77 PAGE OFDetectionBenchmark Performance 111.1 33.033.0Min

  11. Mineral Deformation at Earth's Core-Mantle Boundary

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines light on77 PAGE OFDetectionBenchmark Performance 111.1 33.033.0MinMineral

  12. Mineral Deformation at Earth's Core-Mantle Boundary

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines light on77 PAGE OFDetectionBenchmark Performance 111.1

  13. Mineral Deformation at Earth's Core-Mantle Boundary

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines light on77 PAGE OFDetectionBenchmark Performance 111.1Mineral

  14. Mineral Deformation at Earth's Core-Mantle Boundary

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines light on77 PAGE OFDetectionBenchmark Performance 111.1MineralMineral

  15. Mineral Deformation at Earth's Core-Mantle Boundary

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJessework uses concrete7 Assessment ofLana7,Mimicking the Moon'striadMinding

  16. Mineral Deformation at Earth's Core-Mantle Boundary

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJessework uses concrete7 Assessment ofLana7,Mimicking the

  17. One-vortex moduli space and Ricci flow

    E-Print Network [OSTI]

    Nicholas S. Manton

    2008-05-02

    The metric on the moduli space of one abelian Higgs vortex on a surface has a natural geometrical evolution as the Bradlow parameter, which determines the vortex size, varies. It is shown by various arguments, and by calculations in special cases, that this geometrical flow has many similarities to Ricci flow.

  18. High-Resolution Simulations of Parallel BladeVortex Interactions

    E-Print Network [OSTI]

    Alonso, Juan J.

    to that encountered in the simulation of realistic helicopter blade­vortex interaction, but the computational costs aeroacoustics rotor tests [2,3]. These tests were performed on a Mach-scaled Bo-105 rotor and the blade loadsHigh-Resolution Simulations of Parallel Blade­Vortex Interactions Alasdair Thom University

  19. Finned Tube With Vortex Generators For A Heat Exchanger.

    DOE Patents [OSTI]

    Sohal, Manohar S. (Idaho Falls, ID); O'Brien, James E. (Idaho Falls, ID)

    2005-12-20

    A system for and method of manufacturing a finned tube for a heat exchanger is disclosed herein. A continuous fin strip is provided with at one pair of vortex generators. A tube is rotated and linearly displaced while the continuous fin strip with vortex generators is spirally wrapped around the tube.

  20. Finned Tube With Vortex Generators For A Heat Exchanger.

    DOE Patents [OSTI]

    Sohal, Monohar S. (Idaho Falls, ID); O'Brien, James E. (Idaho Falls, ID)

    2004-09-14

    A system for and method of manufacturing a finned tube for a heat exchanger is disclosed herein. A continuous fin strip is provided with at least one pair of vortex generators. A tube is rotated and linearly displaced while the continuous fin strip with vortex generators is spirally wrapped around the tube.

  1. Disordering transitions in vortex matter: peak effect and phase diagram

    E-Print Network [OSTI]

    Scalettar, Richard T.

    Disordering transitions in vortex matter: peak effect and phase diagram C.J. Olson a,*, C- order nature of this transition. In YBCO a rapid increase in Jc as a function of magnetic field vortex phase diagram as a function of magnetic field and temperature. For increasing field or temperature

  2. Vortex Lattice Modelling of Winglets on Wind Turbine Blades

    E-Print Network [OSTI]

    Vortex Lattice Modelling of Winglets on Wind Turbine Blades Mads Døssing Risø-R-1621(EN) Risø Title: Vortex Lattice Modelling of Winglets on Wind Turbine Blades Departments: Wind Energy Department turbines can be increased by the use of winglets without increasing the swept area. This makes them

  3. Nanolaminate deformable mirrors

    DOE Patents [OSTI]

    Papavasiliou, Alexandros P. (Oakland, CA); Olivier, Scot S. (Santa Cruz, CA)

    2009-04-14

    A deformable mirror formed out of two layers of a nanolaminate foil attached to a stiff substrate is introduced. Deformation is provided by an electrostatic force between two of the layers. The internal stiffness of the structure allows for high-spatial-frequency shapes. The nanolaminate foil of the present invention allows for a high-quality mirror surface. The device achieves high precision in the vertical direction by using foils with accurately controlled thicknesses, but does not require high precision in the lateral dimensions, allowing such mirrors to be fabricated using crude lithography techniques. Such techniques allow structures up to about the meter scale to be fabricated.

  4. Nanolaminate deformable mirrors

    DOE Patents [OSTI]

    Papavasiliou, Alexandros P.; Olivier, Scot S.

    2010-04-06

    A deformable mirror formed out of two layers of a nanolaminate foil attached to a stiff substrate is introduced. Deformation is provided by an electrostatic force between two of the layers. The internal stiffness of the structure allows for high-spatial-frequency shapes. The nanolaminate foil of the present invention allows for a high-quality mirror surface. The device achieves high precision in the vertical direction by using foils with accurately controlled thicknesses, but does not require high precision in the lateral dimensions, allowing such mirrors to be fabricated using crude lithography techniques. Such techniques allow structures up to about the meter scale to be fabricated.

  5. Vortex Molecular Crystal and Vortex Plastic Crystal States in Honeycomb and Kagome Pinning Arrays

    E-Print Network [OSTI]

    C. Reichhardt; C. J. Olson Reichhardt

    2007-07-26

    Using numerical simulations, we investigate vortex configurations and pinning in superconductors with honeycomb and kagome pinning arrays. We find that a variety of novel vortex crystal states can be stabilized at integer and fractional matching field densities. The honeycomb and kagome pinning arrays produce considerably more pronounced commensuration peaks in the critical depinning force than triangular pinning arrays, and also cause additional peaks at noninteger matching fields where a portion of the vortices are located in the large interstitial regions of the pinning lattices. For the honeycomb pinning array, we find matching effects of equal strength at most fillings B/B_\\phi=n/2 for n>2, where n is an integer, in agreement with recent experiments. For kagome pinning arrays, pronounced matching effects generally occur at B/B_\\phi=n/3 for n>3, while for triangular pinning arrays pronounced matching effects are observed only at integer fillings B/B_\\phi=n. At the noninteger matching field peaks in the honeycomb and kagome pinning arrays, the interstitial vortices are arranged in dimer, trimer, and higher order n-mer states that have an overall orientational order. We call these n-mer states "vortex molecular crystals" and "vortex plastic crystals" since they are similar to the states recently observed in colloidal molecular crystal systems. We argue that the vortex molecular crystals have properties in common with certain spin systems such as Ising and n-state Potts models. We show that kagome and honeycomb pinning arrays can be useful for increasing the critical current above that of purely triangular pinning arrays.

  6. Vortex lattice for a holographic superconductor

    E-Print Network [OSTI]

    Kengo Maeda; Makoto Natsuume; Takashi Okamura

    2009-12-17

    We investigate the vortex lattice solution in a (2+1)-dimensional holographic model of superconductors constructed from a charged scalar condensate. The solution is obtained perturbatively near the second-order phase transition and is a holographic realization of the Abrikosov lattice. Below a critical value of magnetic field, the solution has a lower free energy than the normal state. Both the free energy density and the superconducting current are expressed by nonlocal functions, but they reduce to the expressions in the Ginzburg-Landau (GL) theory at long wavelength. As a result, a triangular lattice becomes the most favorable solution thermodynamically as in the GL theory of type II superconductors.

  7. Electron vortex beams in a magnetic field and spin filter

    E-Print Network [OSTI]

    Debashree Chowdhury; Banasri Basu; Pratul Bandyopadhyay

    2015-02-25

    We investigate the propagation of electron vortex beams in a magnetic field. It is pointed out that when electron vortex beams carrying orbital angular momentum propagate in a magnetic field, the Berry curvature associated with the scalar electron moving in a cyclic path around the vortex line is modified from that in free space. This alters the spin-orbit interaction, which affects the propagation of nonparaxial beams. The electron vortex beams with tilted vortex lead to spin Hall effect in free space. In presence of a magnetic field in time space we have spin filtering such that either positive or negative spin states emerge in spin Hall currents with clustering of spin $\\frac{1}{2}$ states.

  8. Dynamics of Magnetized Vortex Tubes in the Solar Chromosphere

    E-Print Network [OSTI]

    Kitiashvili, I N; Mansour, N N; Wray, A A

    2012-01-01

    We use 3D radiative MHD simulations to investigate the formation and dynamics of small-scale (less than 0.5 Mm in diameter) vortex tubes spontaneously generated by turbulent convection in quiet-Sun regions with initially weak mean magnetic fields. The results show that the vortex tubes penetrate into the chromosphere and substantially affect the structure and dynamics of the solar atmosphere. The vortex tubes are mostly concentrated in intergranular lanes and are characterized by strong (near sonic) downflows and swirling motions that capture and twist magnetic field lines, forming magnetic flux tubes that expand with height and which attain magnetic field strengths ranging from 200 G in the chromosphere to more than 1 kG in the photosphere. We investigate in detail the physical properties of these vortex tubes, including thermodynamic properties, flow dynamics, and kinetic and current helicities, and conclude that magnetized vortex tubes provide an important path for energy and momentum transfer from the con...

  9. MEMS Actuated Deformable Mirror

    SciTech Connect (OSTI)

    Papavasiliou, A; Olivier, S; Barbee, T; Walton, C; Cohn, M

    2005-11-10

    This ongoing work concerns the creation of a deformable mirror by the integration of MEMS actuators with Nanolaminate foils through metal compression boning. These mirrors will use the advantages of these disparate technologies to achieve dense actuation of a high-quality, continuous mirror surface. They will enable advanced adaptive optics systems in large terrestrial telescopes. While MEMS actuators provide very dense actuation with high precision they can not provide large forces typically necessary to deform conventional mirror surfaces. Nanolaminate foils can be fabricated with very high surface quality while their extraordinary mechanical properties enable very thin, flexible foils to survive the rigors of fabrication. Precise metal compression bonding allows the attachment of the fragile MEMS actuators to the thin nanolaminate foils without creating distortions at the bond sites. This paper will describe work in four major areas: (1) modeling and design, (2) bonding development, (3) nanolaminate foil development, (4) producing a prototype. A first-principles analytical model was created and used to determine the design parameters. A method of bonding was determined that is both strong, and minimizes the localized deformation or print through. Work has also been done to produce nanolaminate foils that are sufficiently thin, flexible and flat to be deformed by the MEMS actuators. Finally a prototype was produced by bonding thin, flexible nanolaminate foils to commercially available MEMS actuators.

  10. Large vortex state in ferromagnetic disks

    E-Print Network [OSTI]

    Metlov, Konstantin L

    2013-01-01

    Magnetic vortices in soft ferromagnetic nano-disks have been extensively studied for at least several decades both for their fundamental (as a "live" macroscopic realization of a field theory model of an elementary particle) as well as applied value for high-speed high-density power-independent information storage. Here it is shown that there is another vortex state in nano-scale ferromagnetic disks of several exchange lengths in size. The energy of this large vortex state is computed numerically (within the framework of Magnetism@home distributed computing project) and its stability is studied analytically, which allows to plot it on magnetic phase diagram. It is the ground state of cylinders of certain sizes and is metastable in a wider set of geometries. Large vortices exist on par with classical ones, while being separated by an energy barrier, controllable by tuning the geometry and material of ferromagnetic disk. This state can be an excellent candidate for magnetic information storage not only because ...

  11. Multistage interaction of a shock wave and a strong vortex Shuhai Zhanga

    E-Print Network [OSTI]

    Zhang, Yong-Tao

    tube, it traveled back toward the vortex and the interaction between the shock and the vortex tookMultistage interaction of a shock wave and a strong vortex Shuhai Zhanga China Aerodynamics; published online 8 November 2005 The interaction between a shock wave and a strong vortex is simulated

  12. The effect of stoichiometry on vortex flame interactions

    SciTech Connect (OSTI)

    Bell, John B.; Brown, Nancy J.; Day, Marcus S.; Frenklach, Michael; Grcar, Joseph F.; Tonse, Shaheen R.

    1999-12-01

    The interaction of a vortex pair with a premixed flame serves as an important prototype for premixed turbulent combustion. In this study, the authors investigate the interaction of a counter-rotating vortex pair with an initially flat premixed methane flame. The authors focus on characterizing the mechanical nature of the flame-vortex interaction and on the features of the interaction strongly affected by fuel equivalence ratio. The authors compare computational solutions obtained using a time-dependent, two-dimensional adaptive low Mach number combustion algorithm that incorporates GRI-Mech 1.2 for the chemistry, thermodynamics and transport of the chemical species. The authors find that the circulation around the vortex scours gas from the preheat zone in front of the flame, making the interaction extremely sensitive to equivalence ratio. For nearly stoichiometric cases, the peak mole fraction of CH across the flame is relatively insensitive to the vortex whereas for richer flames they observe a substantial and rapid decline in the peak CH mole fraction, commencing early in the flame-vortex interaction. The peak concentration of HCO is found to correlate, in both space and time, with the peak heat release across a broad range of equivalence ratios. The model also predicts a measurable increase in C{sub 2}H{sub 2} as a result of interaction with the vortex, and a marked increase in the low temperature chemistry activity.

  13. Loop-deformed Poincaré algebra

    E-Print Network [OSTI]

    Jakub Mielczarek

    2013-04-08

    In this essay we present evidence suggesting that loop quantum gravity leads to deformation of the local Poincar\\'e algebra within the limit of high energies. This deformation is a consequence of quantum modification of effective off-shell hypersurface deformation algebra. Surprisingly, the form of deformation suggests that the signature of space-time changes from Lorentzian to Euclidean at large curvatures. We construct particular realization of the loop-deformed Poincar\\'e algebra and find that it can be related to curved momentum space, which indicates the relationship with recently introduced notion of relative locality. The presented findings open a new way of testing loop quantum gravity effects.

  14. Partially segmented deformable mirror

    DOE Patents [OSTI]

    Bliss, Erlan S. (Danville, CA); Smith, James R. (Livermore, CA); Salmon, J. Thaddeus (Livermore, CA); Monjes, Julio A. (San Ramon, CA)

    1991-01-01

    A partially segmented deformable mirror is formed with a mirror plate having a smooth and continuous front surface and a plurality of actuators to its back surface. The back surface is divided into triangular areas which are mutually separated by grooves. The grooves are deep enough to make the plate deformable and the actuators for displacing the mirror plate in the direction normal to its surface are inserted in the grooves at the vertices of the triangular areas. Each actuator includes a transducer supported by a receptacle with outer shells having outer surfaces. The vertices have inner walls which are approximately perpendicular to the mirror surface and make planar contacts with the outer surfaces of the outer shells. The adhesive which is used on these contact surfaces tends to contract when it dries but the outer shells can bend and serve to minimize the tendency of the mirror to warp.

  15. Ferroelectric nanostructure having switchable multi-stable vortex states

    DOE Patents [OSTI]

    Naumov, Ivan I. (Fayetteville, AR); Bellaiche, Laurent M. (Fayetteville, AR); Prosandeev, Sergey A. (Fayetteville, AR); Ponomareva, Inna V. (Fayetteville, AR); Kornev, Igor A. (Fayetteville, AR)

    2009-09-22

    A ferroelectric nanostructure formed as a low dimensional nano-scale ferroelectric material having at least one vortex ring of polarization generating an ordered toroid moment switchable between multi-stable states. A stress-free ferroelectric nanodot under open-circuit-like electrical boundary conditions maintains such a vortex structure for their local dipoles when subject to a transverse inhomogeneous static electric field controlling the direction of the macroscopic toroidal moment. Stress is also capable of controlling the vortex's chirality, because of the electromechanical coupling that exists in ferroelectric nanodots.

  16. Experimental deformation of muscovite 

    E-Print Network [OSTI]

    Mares, Vanadis Marina

    1992-01-01

    deformed at 45' to (001) exhibit smooth undulatory extinction associated with dislocation glide, with few low-angle kink band boundaries. Basal shear strengths are insensitive to confining pressure between 100 and 400 MPa. Results for samples shortened... and an exponential constant a of 0. 5+0. 2 MPa-1. Samples loaded parallel to the basal plane shorten by the development of sharply defined kink bands. Strengths associated with kink band formation for samples loaded parallel to (001) are higher than those...

  17. Crystalline Scaling Geometries from Vortex Lattices

    E-Print Network [OSTI]

    Ning Bao; Sarah Harrison

    2013-06-25

    We study magnetic geometries with Lifshitz and/or hyperscaling violation exponents (both with a hard wall cutoff in the IR and a smooth black brane horizon) which have a complex scalar field which couples to the magnetic field. The complex scalar is unstable to the production of a vortex lattice in the IR. The lattice is a normalizable mode which is relevant (i.e. grows into the IR.) When one considers linearized backreaction of the lattice on the metric and gauge field, the metric forms a crystalline structure. We analyze the scaling of the free energy, thermodynamic entropy, and entanglement in the lattice phase and find that in the smeared limit, the leading order correction to thermodynamic properties due to the lattice has the scaling behavior of a theory with a hyperscaling violation exponent between 0 and 1, indicating a flow to an effectively lower-dimensional theory in the deep IR.

  18. Fuel injection of coal slurry using vortex nozzles and valves

    DOE Patents [OSTI]

    Holmes, Allen B. (Rockville, MD)

    1989-01-01

    Injection of atomized coal slurry fuel into an engine combustion chamber is achieved at relatively low pressures by means of a vortex swirl nozzle. The outlet opening of the vortex nozzle is considerably larger than conventional nozzle outlets, thereby eliminating major sources of failure due to clogging by contaminants in the fuel. Control fluid, such as air, may be used to impart vorticity to the slurry and/or purge the nozzle of contaminants during the times between measured slurry charges. The measured slurry charges may be produced by a diaphragm pump or by vortex valves controlled by a separate control fluid. Fluidic circuitry, employing vortex valves to alternatively block and pass cool slurry fuel flow, is disclosed.

  19. Riemannian geometrical constraints on magnetic vortex filaments in plasmas

    E-Print Network [OSTI]

    L. C. Garcia de Andrade

    2005-10-16

    Two theorems on the Riemannian geometrical constraints on vortex magnetic filaments acting as dynamos in (MHD) flows are presented. The use of Gauss-Mainard-Codazzi equations allows us to investigate in detail the influence of curvature and torsion of vortex filaments in the MHD dynamos. This application follows closely previous applications to Heisenberg spin equation to the investigations in magnetohydrostatics given by Schief (Plasma Physics J. 10, 7, 2677 (2003)). The Lorentz force on vortex filaments are computed and the ratio between the forces along different directions are obtained in terms of the ratio between the corresponding magnetic fields which equals also the ratio between the Frenet torsion and vortex line curvature. A similar relation between Lorentz forces, magnetic fields and twist, which is proportional to total torsion integral has been obtained by Ricca (Fluid Dyn. Res. 36,319 (2005)) in the case of inflexional desiquilibrium of magnetic flux-tubes. This is due to the fact that the magnetic vortex lines are a limit case of the magnetic flux-tubes when the lenght of the tube is much greater than the radius of the tube. Magnetic helicity equation of the filament allows us again to determine the magnetic fields ratio from Frenet curvature and torsion of the vortex lines.

  20. Turbine component casting core with high resolution region

    DOE Patents [OSTI]

    Kamel, Ahmed; Merrill, Gary B.

    2014-08-26

    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.

  1. Deformation Expression for Elements of Algebra

    E-Print Network [OSTI]

    H. Omori; Y. Maeda; N. Miyazaki; A. Yoshioka

    2011-04-09

    The purpose of this paper is to give a notion of deformation of expressions for elements of algebra. Deformation quantization (cf.[BF]) deforms the commutative world to a non-commutative world. However, this involves deformation of expression of elements of algebras even from a commutative world to another commutative world. This is indeed a deformation of expressions for elements of algebra.

  2. Alleviation of fuselage form drag using vortex flows: Final report

    SciTech Connect (OSTI)

    Wortman, A.

    1987-09-15

    The concept of using vortex generators to reduce the fuselage form drag of transport aircraft combines the outflow from the plane of symmetry which is induced by the rotational component of the vortex flow with the energization of the boundary layer to reduce the momentum thickness and to delay or eliminate flow separation. This idea was first advanced by the author in 1981. Under a DOE grant, the concept was validated in wind tunnel tests of approximately 1:17 scale models of fuselages of Boeing 747 and Lockheed C-5 aircraft. The search for the minimum drag involved three vortex generator configurations with three sizes of each in six locations clustered in the aft regions of the fuselages at the beginning of the tail upsweep. The local Reynolds number, which is referred to the length of boundary layer run from the nose, was approximately 10{sup 7} so that a fully developed turbulent boundary layer was present. Vortex generator planforms ranged from swept tapered, through swept straight, to swept reverse tapered wings whose semi-spans ranged from 50% to 125% of the local boundary layer thickness. Pitch angles of the vortex generators were varied by inboard actuators under the control of an external proportional digital radio controller. It was found that certain combinations of vortex generator parameters increased drag. However, with certain configurations, locations, and pitch angles of vortex generators, the highest drag reductions were 3% for the 747 and about 6% for the C-5, thus confirming the arguments that effectiveness increases with the rate of upsweep of the tail. Greatest gains in performance are therefore expected on aft loading military transports. 10 refs., 11 figs., 1 tab.

  3. Vortex life cycles in two-and three-layer quasi-geostrophic models 

    E-Print Network [OSTI]

    Fox, Amanda Katherine

    2000-01-01

    regimes with jets has occurred. This research attempted to first determine the typical lifetime of a vortex, with considerations of its birth, evolution, and cessation. A vortex census was also performed in an attempt to describe the life cycle...

  4. Wave–vortex interactions in the nonlinear Schrödinger equation

    SciTech Connect (OSTI)

    Guo, Yuan Bühler, Oliver

    2014-02-15

    This is a theoretical study of wave–vortex interaction effects in the two-dimensional nonlinear Schrödinger equation, which is a useful conceptual model for the limiting dynamics of superfluid quantum condensates at zero temperature. The particular wave–vortex interaction effects are associated with the scattering and refraction of small-scale linear waves by the straining flows induced by quantized point vortices and, crucially, with the concomitant nonlinear back-reaction, the remote recoil, that these scattered waves exert on the vortices. Our detailed model is a narrow, slowly varying wavetrain of small-amplitude waves refracted by one or two vortices. Weak interactions are studied using a suitable perturbation method in which the nonlinear recoil force on the vortex then arises at second order in wave amplitude, and is computed in terms of a Magnus-type force expression for both finite and infinite wavetrains. In the case of an infinite wavetrain, an explicit asymptotic formula for the scattering angle is also derived and cross-checked against numerical ray tracing. Finally, under suitable conditions a wavetrain can be so strongly refracted that it collapses all the way onto a zero-size point vortex. This is a strong wave–vortex interaction by definition. The conditions for such a collapse are derived and the validity of ray tracing theory during the singular collapse is investigated.

  5. Habit tic deformity secondary to guitar playing

    E-Print Network [OSTI]

    Wu, Jashin J

    2009-01-01

    KA. Treatment of habit- tic deformity with fluoxetine. ArchHabit tic deformity secondary to guitar playing Jashin J Wuchanges similar to the habit tic deformity may be produced

  6. Distortion of a Steel Cylinder Casting with a Core D. Galles and C. Beckermann

    E-Print Network [OSTI]

    Beckermann, Christoph

    contraction to introduce stresses and distortions. Therefore, deformation models of both the steel and mold process; the measurements show that thermal expansions (of both the outer mold and core) have an immediate are predicted in the core and casting; the results suggest 1) the thermal expansion coefficient of the mold

  7. Resonant amplification of vortex-core oscillations by coherent magnetic-field pulses

    E-Print Network [OSTI]

    Yu, Young-Sang

    2014-01-01

    2002). 41. Cowburn, R. P. Spintronics: Change of direction.Past achievements in spintronics have largely relied on an

  8. Molecular tagging velocimetry measurements of axial flow in a concentrated vortex core

    E-Print Network [OSTI]

    Koochesfahani, Manoochehr M.

    , hydrocyclones) and natural (e.g., tornadoes, hurricanes, dust devils) flow fields. The interaction of vortices

  9. Finite Element Modeling of Drilling Using DEFORM

    E-Print Network [OSTI]

    Gardner, Joel D.; Dornfeld, David

    2006-01-01

    Vijayaraghavan, A. (2005), “Drilling of Fiber- ReinforcedFINITE ELEMENT MODELING OF DRILLING USING DEFORM J. Gardner,of Comprehensive Drilling Simulation Tool” ABSTRACT DEFORM-

  10. The Effects of Wind Tunnel Walls on the Near-field Behavior of a Wingtip Vortex

    E-Print Network [OSTI]

    Hu, Hui

    /vortex interaction on helicopter blades can impact performance and cause undesirable noise and vibration. Vortex completely. This method was applied to investigate the effects of the angle of attack of the test wing vortex structures on dynamics of towed vehicles, tail buffeting, and icing arrays. Blade

  11. Vortex Rings in Bio-inspired and Biological Jet Propulsion Paul S. Krueger1, a

    E-Print Network [OSTI]

    Horth, Lisa

    of the latter, vortex rings are generated by the transient ejection of a jet from a tube or orifice, which leadsVortex Rings in Bio-inspired and Biological Jet Propulsion Paul S. Krueger1, a , Ali A. Moslemi1,b@odu.edu, e wstewart@uci.edu Keywords: Vortex rings, pulsed jets, propulsion, thrust, propulsive efficiency

  12. Vortex pinning in super-conductivity as a rate-independent process

    E-Print Network [OSTI]

    Mielke, Alexander

    : R the magnetic field perpendicular to the plane. The vortex tube density : R is related to ~H via for this case. The modeling assumption in [Cha00] is now that the vortex tubes will not move if the modulus the conservation of the vortex-tube density which is driven by the current J. The second line contains

  13. PHYSICAL REVIEW E 78, 036304 2008 Variational principle in dynamics of a vortex ...lament

    E-Print Network [OSTI]

    Berdichevsky, Victor

    A vortex ...lament is a thin tube such that vorticity is negligible in a vicinity of this tube while insidePHYSICAL REVIEW E 78, 036304 2008 Variational principle in dynamics of a vortex ...lament Victor L in dynamics of vortex ...lament Victor L. Berdichevsky Mechanical Engineering, Wayne State University, Detroit

  14. COLLISIONS OF VORTEX FILAMENT PAIRS VALERIA BANICA, ERWAN FAOU, AND EVELYNE MIOT

    E-Print Network [OSTI]

    Faou, Erwan

    COLLISIONS OF VORTEX FILAMENT PAIRS VALERIA BANICA, ERWAN FAOU, AND EVELYNE MIOT Abstract. We consider the problem of collisions of vortex filaments for a model introduced by Klein, Majda and Damodaran [KMD95] and Zakharov [Z88, Z99] to describe the interaction of almost parallel vortex filaments

  15. Ubiquitous Solar Eruptions Driven by Magnetized Vortex Tubes

    E-Print Network [OSTI]

    Kitiashvili, I N; Lele, S K; Mansour, N N; Wray, A A

    2013-01-01

    The solar surface is covered by high-speed jets transporting mass and energy into the solar corona and feeding the solar wind. The most prominent of these jets have been known as spicules. However, the mechanism initiating these eruptions events is still unknown. Using realistic numerical simulations we find that small-scale eruptions are produced by ubiquitous magnetized vortex tubes generated by the Sun's turbulent convection in subsurface layers. The swirling vortex tubes (resembling tornadoes) penetrate into the solar atmosphere, capture and stretch background magnetic field, and push surrounding material up, generating quasiperiodic shocks. Our simulations reveal a complicated high-speed flow patterns, and thermodynamic and magnetic structure in the erupting vortex tubes. We found that the eruptions are initiated in the subsurface layers and are driven by the high-pressure gradients in the subphotosphere and photosphere, and by the Lorentz force in the higher atmosphere layers.

  16. Optical vortex driven charge current loop and optomagnetism in fullerenes

    E-Print Network [OSTI]

    Wätzel, Jonas; Schäffer, Alexander; Berakdar, Jamal

    2016-01-01

    Endohedral molecular magnets, e.g. as realized in fullerenes containing $\\rm DySc_{2}N$, are promising candidates for molecular electronics and quantum information processing. For their functionalization an ultrafast local magnetization control is essential. Using full ab-initio quantum chemistry calculations we predict the emergence of charge current loops in fullerenes with an associated orbital magnetic moment upon irradiation with weak light vortex pulses that transfer orbital angular momentum. The generated current is controllable by the frequency, the vortex topological charge, and the intensity of the light. Numerical and analytical results show that an ultraviolet vortex femtosecond pulse with an intensity $\\sim10^{13}$ W/cm$^2$ generates non-invasively nA unidirectional surface current with an associated magnetic field of hundreds $\\mu$T at the center of the fullerene.

  17. Low Head, Vortex Induced Vibrations River Energy Converter

    SciTech Connect (OSTI)

    Bernitsas, Michael B.; Dritz, Tad

    2006-06-30

    Vortex Induced Vibrations Aquatic Clean Energy (VIVACE) is a novel, demonstrated approach to extracting energy from water currents. This invention is based on a phenomenon called Vortex Induced Vibrations (VIV), which was first observed by Leonardo da Vinci in 1504AD. He called it ‘Aeolian Tones.’ For decades, engineers have attempted to prevent this type of vibration from damaging structures, such as offshore platforms, nuclear fuel rods, cables, buildings, and bridges. The underlying concept of the VIVACE Converter is the following: Strengthen rather than spoil vortex shedding; enhance rather than suppress VIV; harness rather than mitigate VIV energy. By maximizing and utilizing this unique phenomenon, VIVACE takes this “problem” and successfully transforms it into a valuable resource for mankind.

  18. Small Winding-Number Expansion: Vortex Solutions at Critical Coupling

    E-Print Network [OSTI]

    Keisuke Ohashi

    2015-07-22

    We study an axially symmetric solution of a vortex in the Abelian-Higgs model at critical coupling in detail. Here we propose a new idea for a perturbative expansion of a solution, where the winding number of a vortex is naturally extended to be a real number and the solution is expanded with respect to it around its origin. We test this idea on three typical constants contained in the solution and confirm that this expansion works well with the help of the Pad\\'e approximation. For instance, we analytically reproduce the value of the scalar charge of the vortex with an error of $O(10^{-6})$. This expansion is also powerful even for large winding numbers.

  19. Small Winding-Number Expansion: Vortex Solutions at Critical Coupling

    E-Print Network [OSTI]

    Keisuke Ohashi

    2015-09-01

    We study an axially symmetric solution of a vortex in the Abelian-Higgs model at critical coupling in detail. Here we propose a new idea for a perturbative expansion of a solution, where the winding number of a vortex is naturally extended to be a real number and the solution is expanded with respect to it around its origin. We test this idea on three typical constants contained in the solution and confirm that this expansion works well with the help of the Pad\\'e approximation. For instance, we analytically reproduce the value of the scalar charge of the vortex with an error of $O(10^{-6})$. This expansion is also powerful even for large winding numbers.

  20. Small Winding-Number Expansion: Vortex Solutions at Critical Coupling

    E-Print Network [OSTI]

    Ohashi, Keisuke

    2015-01-01

    We study an axially symmetric solution of a vortex in the Abelian-Higgs model at critical coupling in detail. Here we propose a new idea for a perturbative expansion of a solution, where the winding number of a vortex is naturally extended to be a real number and the solution is expanded with respect to it around its origin. We test this idea on three typical constants contained in the solution and confirm that this expansion works well with the help of the Pad\\'e approximation. For instance, we analytically reproduce the value of the scalar charge of the vortex with an error of $O(10^{-6})$. This expansion is also powerful even for large winding numbers.

  1. Deformed diffusion and generalized Laplacian for directed networks

    E-Print Network [OSTI]

    Michaël Fanuel; Johan A. K. Suykens

    2015-11-02

    A diffusion equation on a complex network is usually implemented with the help of the combinatorial Laplacian which incorporates information about the network structure. In this paper, a deformed diffusion equation on directed networks, governed by a generalized Laplacian, is introduced within a framework of discrete differential forms, closely related to combinatorial Hodge theory. Edge directions are incorporated with the help of an edge flow $1$-form, whose deforming impact is controlled by a coupling constant. Hence, information about the community structure is encoded in the dominant modes in the long time limit. On the one hand, for a small deformation of the combinatorial Laplacian, the dominant modes of the deformed diffusion allow to uncover community structures which are only encoded in the edge directions. We show that the dynamics distinguishes two categories of nodes, i.e. the nodes with a majority of outgoing links from the nodes with a majority of incoming links. Furthermore, the categorization naturally implements the connectivity of nodes and hence, goes beyond a simple degree counting. On the other hand, in the case of maximal deformation, the dominant modes of the dynamics characterize important nodes of the directed network that we name Bi-directional Outer Cores (BOC's) and Bi-directional Inner Cores (BIC's) which are the analogue of connected components of undirected networks. These BIC's and BOC's are shown to support stationary distributions. The relevance of these aspects is illustrated on a series of artificial and real-life directed networks such as a food web and a neuronal network.

  2. 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...

  3. Exploiting lens aberrations to create electron vortex beams

    E-Print Network [OSTI]

    L. Clark; A. Béché; G. Guzzinati; A. Lubk; M. Mazilu; R. Van Boxem; J. Verbeeck

    2013-07-18

    A model for a new electron vortex beam production method is proposed and experimentally demonstrated. The technique calls on the controlled manipulation of the degrees of freedom of the lens aberrations to achieve a helical phase front. These degrees of freedom are accessible by using the corrector lenses of a transmission electron microscope. The vortex beam is produced through a particular alignment of these lenses into a specifically designed astigmatic state and applying an annular aperture in the condensor plane. Experimental results are found to be in good agreement with simulations.

  4. A Non-Abelian Vortex Lattice in Strongly Coupled Systems

    E-Print Network [OSTI]

    Kenny Wong

    2013-10-09

    The AdS/CFT correspondence predicts that background non-abelian magnetic fields induce instabilities in strongly-coupled systems with non-abelian global symmetries. These instabilities lead to the formation of vortex lattices in which the non-abelian currents "antiscreen" the applied magnetic field. From the bulk perspective, this behaviour can be traced to a well-known instability of Yang-Mills theory. We analyse the phase structure of the instability and comment on aspects of the vortex lattice.

  5. Laboratory Analysis of Vortex Dynamics For Shallow Tidal Inlets 

    E-Print Network [OSTI]

    Whilden, Kerri Ann

    2010-10-12

    OF VORTEX DYNAMICS FOR SHALLOW TIDAL INLETS A Thesis by KERRI ANN WHILDEN Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment of the requirements for the degree of MASTER OF SCIENCE August 2009 Major Subject: Ocean... Engineering LABORATORY ANALYSIS OF VORTEX DYNAMICS FOR SHALLOW TIDAL INLETS A Thesis by KERRI ANN WHILDEN Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment of the requirements for the degree of MASTER OF SCIENCE Approved...

  6. Experimental investigation of magnetic anisotropy in spin vortex discs

    SciTech Connect (OSTI)

    Garraud, N. Arnold, D. P.

    2014-05-07

    We present experimental 2D vector vibrating sample magnetometer measurements to demonstrate the shape anisotropy effects occurring in micrometer-diameter supermalloy spin vortex discs. Measurements made for different disc sizes and orientations confirm the out-of-plane susceptibility is several orders of magnitude smaller than the in-plane susceptibility. These results validate with a high certitude that spin vortices with high diameter to thickness ratio retain in-plane-only magnetization, even when subjected to fields in the out-of-plane direction. These results contribute to further computational simulations of the dynamics of spin vortex structures in colloidal suspensions where external fields may be applied in any arbitrary direction.

  7. Variable focal length deformable mirror

    SciTech Connect (OSTI)

    Headley, Daniel (Albuquerque, NM); Ramsey, Marc (Albuquerque, NM); Schwarz, Jens (Albuquerque, NM)

    2007-06-12

    A variable focal length deformable mirror has an inner ring and an outer ring that simply support and push axially on opposite sides of a mirror plate. The resulting variable clamping force deforms the mirror plate to provide a parabolic mirror shape. The rings are parallel planar sections of a single paraboloid and can provide an on-axis focus, if the rings are circular, or an off-axis focus, if the rings are elliptical. The focal length of the deformable mirror can be varied by changing the variable clamping force. The deformable mirror can generally be used in any application requiring the focusing or defocusing of light, including with both coherent and incoherent light sources.

  8. Vortex Diode Analysis and Testing for Fluoride Salt-Cooled High-Temperature Reactors

    SciTech Connect (OSTI)

    Yoder Jr, Graydon L [ORNL; Elkassabgi, Yousri M. [Texas A& M University, Kingsville; De Leon, Gerardo I. [Texas A& M University, Kingsville; Fetterly, Caitlin N. [Texas A& M University, Kingsville; Ramos, Jorge A. [Texas A& M University, Kingsville; Cunningham, Richard Burns [University of Tennessee, Knoxville (UTK)

    2012-02-01

    Fluidic diodes are presently being considered for use in several fluoride salt-cooled high-temperature reactor designs. A fluidic diode is a passive device that acts as a leaky check valve. These devices are installed in emergency heat removal systems that are designed to passively remove reactor decay heat using natural circulation. The direct reactor auxiliary cooling system (DRACS) uses DRACS salt-to-salt heat exchangers (DHXs) that operate in a path parallel to the core flow. Because of this geometry, under normal operating conditions some flow bypasses the core and flows through the DHX. A flow diode, operating in reverse direction, is-used to minimize this flow when the primary coolant pumps are in operation, while allowing forward flow through the DHX under natural circulation conditions. The DRACSs reject the core decay heat to the environment under loss-of-flow accident conditions and as such are a reactor safety feature. Fluidic diodes have not previously been used in an operating reactor system, and therefore their characteristics must be quantified to ensure successful operation. This report parametrically examines multiple design parameters of a vortex-type fluidic diode to determine the size of diode needed to reject a particular amount of decay heat. Additional calculations were performed to size a scaled diode that could be tested in the Oak Ridge National Laboratory Liquid Salt Flow Loop. These parametric studies have shown that a 152.4 mm diode could be used as a test article in that facility. A design for this diode is developed, and changes to the loop that will be necessary to test the diode are discussed. Initial testing of a scaled flow diode has been carried out in a water loop. The 150 mm diode design discussed above was modified to improve performance, and the final design tested was a 171.45 mm diameter vortex diode. The results of this testing indicate that diodicities of about 20 can be obtained for diodes of this size. Experimental results show similar trends as the computational fluid dynamics (CFD) results presented in this report; however, some differences exist that will need to be assessed in future studies. The results of this testing will be used to improve the diode design to be tested in the liquid salt loop system.

  9. The Fabric of Clasts, Veins and Foliations within the Actively Creeping Zones of the San Andreas Fault at SAFOD: Implications for Deformation Processes 

    E-Print Network [OSTI]

    Sills, David Wayne

    2012-02-14

    Recovered core samples from the San Andreas Fault Observatory at Depth (SAFOD), located near Parkfield, CA, offer a unique opportunity to study the products of faulting and to learn about the mechanisms of slip at 3 km depth. Casing deformation...

  10. Deformed Mittag-Leffler Polynomials

    E-Print Network [OSTI]

    Stankovic, Miomir S; Rajkovic, Predrag M

    2010-01-01

    The starting point of this paper are the Mittag-Leffler polynomials introduced by H. Bateman [1]. Based on generalized integer powers of real numbers and deformed exponential function, we introduce deformed Mittag-Leffler polynomials defined by appropriate generating function. We investigate their recurrence relations, differential properties and orthogonality. Since they have all zeros on imaginary axes, we also consider real polynomials with real zeros associated to them.

  11. Investigation of Vortex Structures in Gas-Discharge Nonneutral Electron Plasma: IV. Pulse Ejection of Electrons at the mutual interaction of Vortex Structures

    E-Print Network [OSTI]

    Kervalishvili, N A

    2015-01-01

    The results of experimental investigations of the ejection of electrons from gas-discharge nonneutral electron plasma at interaction of vortex structures have been given. The periodical approach of vortex structures causes the ejection of electrons both from the vortex structures themselves and from the adjacent regions of electron sheath to the end cathodes of discharge device. The ejection takes place in the form of short and long pulses following each other. The nature of these pulses and the dynamics of interaction of vortex structures at their approach were studied.

  12. Elliptic vortex patches: coasts and chaos Andrew Crosby

    E-Print Network [OSTI]

    Lebovitz, Norman

    are important for the transport of heat/salt across the Atlantic and, due to their relatively long life-times (O of such ocean vortices as point vortices and analysing their paths around islands or past coastal gaps presented by Ted were that of motion around a pair of islands (see Figure 2a) where the vortex patch might

  13. -STABILITY AND VORTEX MOTION IN TYPE II SUPERCONDUCTORS

    E-Print Network [OSTI]

    Spirn, Daniel

    -STABILITY AND VORTEX MOTION IN TYPE II SUPERCONDUCTORS MATTHIAS KURZKE AND DANIEL SPIRN Abstract. 1. Introduction 1.1. Physical background. The evolution of a superconducting material is usu- ally of the magnetic field and the electric field potential for a superconducting sample R2 . The parameter

  14. Vortex Rings in a Stratified Fluid M. M. Scase

    E-Print Network [OSTI]

    Dalziel, Stuart

    in a stratified fluid, are developed. These models include both buoyancy forces and the drag due to the generation to investigate the waves generated by the propagation of the vortex ring, the ring is modelled as a sphere, based for describing these wavefronts is given. The drag due to the generated internal wave field is calculated

  15. WAVE-VORTEX INTERACTIONS IN THE ATMOSPHERE, AND CLIMATE

    E-Print Network [OSTI]

    Al Hanbali, Ahmad

    WAVE-VORTEX INTERACTIONS IN THE ATMOSPHERE, AND CLIMATE PREDICTION Onno Bokhove Numerical Analysis, The Netherlands o.bokhove@math.utwente.nl Abstract Can we construct an accurate atmospheric climate model parcel dynamics, linear modes, balan- ced models, gravity waves, weather and climate prediction

  16. Modified Black Hole with Polar Jet and Vortex

    E-Print Network [OSTI]

    T. Tmmalm

    2001-12-06

    There are many models relating an accretion disk of Black Hole to jet outflow. The herein heuristic model describes the continuation of an external accretion disk to an internal accretion disk for less than Black Hole horizon, and subsequent polar jet outflow along polar axis out of polar vortex wherein the event horizon is no longer descriptive.

  17. MOI OF PATTERN FORMATION IN THE VORTEX LANDSCAPE

    E-Print Network [OSTI]

    Wijngaarden, Rinke J.

    1081, 1081 HV Amsterdam, The Netherlands RW@NAT.VU.NL Abstract Due to the occurence of punctuations front were reported by Surdeanu et al.[1]. To local vortex density in the type-II YBa2Cu3O7

  18. Numerical Approximation of Vortex Density Evolution in a Superconductor.

    E-Print Network [OSTI]

    Styles, Vanessa

    Numerical Approximation of Vortex Density Evolution in a Superconductor. C.M. Elliott & V. Styles Abstract A #12;nite volume/element approximation of a mean #12;eld model of superconducting vortices in one approximations of a two-dimensional version of the mean #12;eld model of superconducting vortices considered

  19. Planet Embryos in Vortex Wombs Joseph A. Barranco

    E-Print Network [OSTI]

    Marcus, Philip S.

    Planet Embryos in Vortex Wombs Joseph A. Barranco and Philip S. Marcus Dept. of Astronomy gravitating planetesimals, the "build- ing blocks" of planets. One theory is that the dust grains settle into the mid-plane of the protoplane- tary disk (thin, cool disk of gas and dust in orbit around a newly

  20. Biomedical Engineering Correlation Between Vortex Ring Formation and Mitral

    E-Print Network [OSTI]

    Kheradvar, Arash

    was generated during fluid propulsion and that it is maximal for an annulus diameter close to the normal adult typically develop from a jet or slug of fluid ejected from a nozzle. In fluid mechanics, mitral inflow fluid phenomena observed in the left ventricle during diastole is the presence of vortex rings

  1. Vortex stabilized electron beam compressed fusion grade plasma

    SciTech Connect (OSTI)

    Hershcovitch, Ady

    2014-03-19

    Most inertial confinement fusion schemes are comprised of highly compressed dense plasmas. Those schemes involve short, extremely high power, short pulses of beams (lasers, particles) applied to lower density plasmas or solid pellets. An alternative approach could be to shoot an intense electron beam through very dense, atmospheric pressure, vortex stabilized plasma.

  2. VORTEX: Design and Implementation of an Interactive Volumetric Display

    E-Print Network [OSTI]

    Subramanian, Sriram

    VORTEX: Design and Implementation of an Interactive Volumetric Display Abstract True 3D display systems like volumetric displays allow generation of autostereoscopic, multi-view 3D content that has real custom volumetric display from easily available components. By building a touch-enabled volumetric

  3. Permeability evolution during progressive development of deformation bands in porous sandstones

    E-Print Network [OSTI]

    Permeability evolution during progressive development of deformation bands in porous sandstones B carried out on large (0.1 m) diameter cores of a porous sandstone in order to investigate the evolution from measured bulk parameters. In a test of the model for Clashach sandstone, the parameters vary

  4. Shape of Lambda hypernuclei in (beta,gamma) deformation plane

    E-Print Network [OSTI]

    Myaing Thi Win; K. Hagino; T. Koike

    2010-12-15

    We study the shape of $\\Lambda$ hypernuclei in the full ($\\beta,\\gamma$) deformation plane, including both axially symmetric and triaxial quadrupole deformations. To this end, we use the constrained Skyrme Hartree-Fock+BCS method on the three-dimensional Cartesian mesh. The potential energy surface is analyzed for carbon hypernuclei as well as for sd-shell hypernuclei such as $^{27,29}_{\\Lambda}$Si and $^{25,27}_{\\Lambda}$Mg. We show that the potential energy surface in the ($\\beta,\\gamma$) plane is similar to each other between the hypernuclei and the corresponding core nuclei, although the addition of $\\Lambda$ hyperon makes the energy surface somewhat softer along the $\\gamma$ direction. Our calculation implies that the energy of the $\\gamma$ vibration for $^{25,27}_{\\Lambda}$Mg nuclei is lowered by about 0.15 MeV with respect to that of $^{24,26}$Mg nuclei.

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

    E-Print Network [OSTI]

    Lasbleis, M; Cardin, P; Labrosse, S

    2015-01-01

    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...

  6. Thermal barrier and support for nuclear reactor fuel core

    DOE Patents [OSTI]

    Betts, Jr., William S. (Del Mar, CA); Pickering, J. Larry (Del Mar, CA); Black, William E. (San Diego, CA)

    1987-01-01

    A thermal barrier/core support for the fuel core of a nuclear reactor having a metallic cylinder secured to the reactor vessel liner and surrounded by fibrous insulation material. A top cap is secured to the upper end of the metallic cylinder that locates and orients a cover block and post seat. Under normal operating conditions, the metallic cylinder supports the entire load exerted by its associated fuel core post. Disposed within the metallic cylinder is a column of ceramic material, the height of which is less than that of the metallic cylinder, and thus is not normally load bearing. In the event of a temperature excursion beyond the design limits of the metallic cylinder and resulting in deformation of the cylinder, the ceramic column will abut the top cap to support the fuel core post.

  7. 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

  8. Pressurized water nuclear reactor system with hot leg vortex mitigator

    DOE Patents [OSTI]

    Lau, Louis K. S. (Monroeville, PA)

    1990-01-01

    A pressurized water nuclear reactor system includes a vortex mitigator in the form of a cylindrical conduit between the hot leg conduit and a first section of residual heat removal conduit, which conduit leads to a pump and a second section of residual heat removal conduit leading back to the reactor pressure vessel. The cylindrical conduit is of such a size that where the hot leg has an inner diameter D.sub.1, the first section has an inner diameter D.sub.2, and the cylindrical conduit or step nozzle has a length L and an inner diameter of D.sub.3 ; D.sub.3 /D.sub.1 is at least 0.55, D.sub.2 is at least 1.9, and L/D.sub.3 is at least 1.44, whereby cavitation of the pump by a vortex formed in the hot leg is prevented.

  9. Magneto-Vortex Dynamo Model in Solar convection zone

    E-Print Network [OSTI]

    Sergey V. Ershkov

    2011-01-06

    Here is presented a new magneto-vortex dynamo model for modeling & predicting of a processes in Solar plasma convection zone. Solar convection zone is located above the level r > 0,6-0,7 R, where R is a Solar radius. A key feature of such a model is that equation of Solar plasma motion as well as equation of magnetic fields evolution - are reduced to Helmholtz's vortex equation, which is up-graded in according with alpha-effect (Coriolis force forms an additional vorticity field or magnetic field due to Sun's differential rotation). Such an additional vorticity or magnetic field are proved to be concentrated at the proper belt in Solar convection zone under the influence of Coriolis force (at the middle latitudes of the Sun in respect to equator). Besides, such an an additional vorticity & magnetic fields are to be the basic sources of well-known phenomena "Maunder's butterfly" diagram.

  10. Highly efficient electron vortex beams generated by nanofabricated phase holograms

    SciTech Connect (OSTI)

    Grillo, Vincenzo; Mafakheri, Erfan; Frabboni, Stefano

    2014-01-27

    We propose an improved type of holographic-plate suitable for the shaping of electron beams. The plate is fabricated by a focused ion beam on a silicon nitride membrane and introduces a controllable phase shift to the electron wavefunction. We adopted the optimal blazed-profile design for the phase hologram, which results in the generation of highly efficient (25%) electron vortex beams. This approach paves the route towards applications in nano-scale imaging and materials science.

  11. Vortex energy and 360 Neel walls in thinfilm

    E-Print Network [OSTI]

    .Ignat@math.u-psud.fr) Courant Institute, New York University, New York, NY 10012, USA (e-mail: knuepfer@cims.nyu.edu) 1 #12Vortex energy and 360 ­N´eel walls in thin­film micromagnetics Radu Ignat , Hans Kn¨upfer October-section. The model is based on the following energy functional: E2d (m) = Z B2 |m|2 dx + | ln | 2 Z R2 ||-1

  12. Vortex energy and 360 Neel wall in thinfilm

    E-Print Network [OSTI]

    Ignat, Radu

    .Ignat@math.u-psud.fr) Courant Institute, New York University, New York, NY 10012, USA (e-mail: knuepfer@cims.nyu.edu) 1 #12Vortex energy and 360 ­N´eel wall in thin­film micromagnetics Radu Ignat , Hans Kn¨upfer October-section. The model is based on the following energy functional: E2d (m) = Z B2 |m|2 dx + | ln | 2 Z R2 ||-1

  13. Negative specific heat for quasi-2D vortex structures in electron plasmas: an explicit, closed-form derivation

    E-Print Network [OSTI]

    T. D. Andersen; C. C. Lim

    2008-02-29

    Negative specific heat is a dramatic phenomenon where processes decrease in temperature when adding energy. It has been observed in gravo-thermal collapse of globular clusters. We now report finding this phenomenon in bundles of nearly parallel, periodic, single-sign generalized vortex filaments in the electron magnetohydrodynamic (EMH) model for the unbounded plane under strong magnetic confinement. We derive the specific heat using a steepest descent method and a mean field property. Our derivations show that as temperature increases, the overall size of the system increases exponentially and the energy drops. The implication of negative specific heat is a runaway reaction, resulting in a collapsing inner core surrounded by an expanding halo of filaments.

  14. To mechanics of deformation, flow, and fracture

    E-Print Network [OSTI]

    S. L. Arsenjev

    2008-09-23

    It is stated in the main in essence new approach to mechanics of the stressed state of the solid body from statistically isotropic material and the homogeneous liquid dynamics. The approach essence is in the detected property of the core-shell spontaneous structurization of internal energy of the solid and liquid bodies in its natural state and under action of external forces. The method elements of construction of physically adequate model of the stressed state of the solid and liquid bodies, reproduced exactly its behavior on the stages of elastic and plastic deformation, flow and fracture, are stated. It is adduced a number of the examples of the stressed state construction of the simple form bodies under action of its tension, compression, torsion and at its contact interaction. For the first time it is adduced structure of the principal - normal - stresses in cylindrical bar under action of the torsion moment. The detected property and the developed method is one of necessary bases for construction of physically adequate mathematical model of the stressed state of the body and fluid in contrast to traditional approach.

  15. Equilibrium vortex motion in two- and three-dimensional suprconductors studied with a dc SQUID

    E-Print Network [OSTI]

    Shaw, Timothy J.

    2010-01-01

    is determined by thermal activation between pinning sites.is determined by thermal activation, it is important tothe SQUID washer. Thermal activation of the vortex between

  16. Hummingbirds generate bilateral vortex loops during hovering: evidence from flow visualization

    E-Print Network [OSTI]

    Pournazeri, Sam; Segre, Paolo; Princevac, Marko; Altshuler, Douglas

    2012-01-01

    energetic cost of flight (Rayner and Gordon 1998; Hedenstro¨generates one vortex ring per stroke (Rayner 1979; Ellington1984; Pennycuick 1988; Rayner and Gordon 1998), which would

  17. Quantum mechanical effects from deformation theory

    SciTech Connect (OSTI)

    Much, A. [Max-Planck-Institute for Mathematics in the Sciences, 04103 Leipzig, Germany and Institute for Theoretical Physics, University of Leipzig, 04009 Leipzig (Germany)] [Max-Planck-Institute for Mathematics in the Sciences, 04103 Leipzig, Germany and Institute for Theoretical Physics, University of Leipzig, 04009 Leipzig (Germany)

    2014-02-15

    We consider deformations of quantum mechanical operators by using the novel construction tool of warped convolutions. The deformation enables us to obtain several quantum mechanical effects where electromagnetic and gravitomagnetic fields play a role. Furthermore, a quantum plane can be defined by using the deformation techniques. This in turn gives an experimentally verifiable effect.

  18. Midland Core Repository

    SciTech Connect (OSTI)

    Tyler, Noel

    2000-08-14

    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.

  19. Core assembly storage structure

    DOE Patents [OSTI]

    Jones, Jr., Charles E. (Northridge, CA); Brunings, Jay E. (Chatsworth, CA)

    1988-01-01

    A structure for the storage of core assemblies from a liquid metal-cooled nuclear reactor. The structure comprises an enclosed housing having a substantially flat horizontal top plate, a bottom plate and substantially vertical wall members extending therebetween. A plurality of thimble members extend downwardly through the top plate. Each thimble member is closed at its bottom end and has an open end adjacent said top plate. Each thimble member has a length and diameter greater than that of the core assembly to be stored therein. The housing is provided with an inlet duct for the admission of cooling air and an exhaust duct for the discharge of air therefrom, such that when hot core assemblies are placed in the thimbles, the heat generated will by convection cause air to flow from the inlet duct around the thimbles and out the exhaust duct maintaining the core assemblies at a safe temperature without the necessity of auxiliary powered cooling equipment.

  20. Emergency core cooling system

    DOE Patents [OSTI]

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

    1983-01-01

    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.

  1. MCNP LWR Core Generator

    SciTech Connect (OSTI)

    Fischer, Noah A.

    2012-08-14

    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.

  2. Is inner core seismic anisotropy a marker of plastic flow of cubic iron?

    E-Print Network [OSTI]

    Lincot, A; Cardin, Philippe

    2015-01-01

    This paper investigates whether observations of seismic anisotropy are compatible with a cubic structure of the inner core Fe alloy. We assume that anisotropy is the result of plastic deformation within a large scale flow induced by preferred growth at the inner core equator. Based on elastic moduli from the literature, bcc- or fcc-Fe produce seismic anisotropy well below seismic observations ($\\textless{}0.4\\%$). A Monte-Carlo approach allows us to generalize this result to any form of elastic anisotropy in a cubic system. Within our model, inner core global anisotropy is not compatible with a cubic structure of Fe alloy. Hence, if the inner core material is indeed cubic, large scale coherent anisotropic structures, incompatible with plastic deformation induced by large scale flow, must be present.

  3. Noncommutative supergeometry, duality and deformations

    E-Print Network [OSTI]

    Albert Schwarz

    2002-10-28

    We introduce a notion of $Q$-algebra that can be considered as a generalization of the notion of $Q$-manifold (a supermanifold equipped with an odd vector field obeying $\\{Q,Q\\} =0$). We develop the theory of connections on modules over $Q$-algebras and prove a general duality theorem for gauge theories on such modules. This theorem containing as a simplest case $SO(d,d,{\\bf Z})$-duality of gauge theories on noncommutative tori can be applied also in more complicated situations. We show that $Q$-algebras appear naturally in Fedosov construction of formal deformation of commutative algebras of functions and that similar $Q$-algebras can be constructed also in the case when the deformation parameter is not formal.

  4. Vortex-induced vibration of a circular cylinder with combined in-line and cross-flow motion

    E-Print Network [OSTI]

    Dahl, Jason (Jason Michael)

    2008-01-01

    Deep water, string-like, marine risers subject to strong ocean currents, suffer from vortex-induced vibrations (VIV), where vortex shedding interacts with the structural properties of the riser, resulting in large amplitude ...

  5. All-University Core Curriculum All-University Core Curriculum

    E-Print Network [OSTI]

    All-University Core Curriculum All-University Core Curriculum Office of Vice Provost-UNIVERSITY CORE CURRICULUM (AUCC) All Colorado State University students share a learning experience in common recommendations for satisfying All- University Core Curriculum requirements. A student must earn a cumulative

  6. All-University Core Curriculum All-University Core Curriculum

    E-Print Network [OSTI]

    Collett Jr., Jeffrey L.

    All-University Core Curriculum _______________ 2.3 Page 1 All-University Core Curriculum Office-UNIVERSITY CORE CURRICULUM (AUCC) All Colorado State University students share a learning experience in common if their preferred program of study has particular recommendations for satisfying All- University Core Curriculum

  7. The role of vortex wake dynamics in the flow-induced vibration of tube arrays

    E-Print Network [OSTI]

    Kevlahan, Nicholas

    The role of vortex wake dynamics in the flow-induced vibration of tube arrays N.K.-R. Kevlahan Keywords: Fluid­structure interaction Vortex-induced vibration Tube arrays Potential flow a b s t r a c in the non-resonant flow-induced vibration of periodic tube arrays. This dual approach untangles the effects

  8. Determination of magnetic vortex chirality using lateral spin-valve and Y. Otani

    E-Print Network [OSTI]

    Otani, Yoshichika

    Determination of magnetic vortex chirality using lateral spin-valve geometry T. Kimuraa and Y October 2005 We demonstrate the determination of the vortex chirality using a nonlocal spin-valve measurement technique in a lateral spin valve consisting of a Permalloy Py disk 1 m in diameter and a Py wire

  9. Laminar Flow of a Sheared Vortex Crystal: Scars in Flat Geometry M.-Carmen Miguel,1

    E-Print Network [OSTI]

    Miguel-Lopez, Carmen

    Laminar Flow of a Sheared Vortex Crystal: Scars in Flat Geometry M.-Carmen Miguel,1 Adil Mughal,2 November 2010; published 15 June 2011) We consider the laminar flow of a vortex crystal in the Corbino disk geometry. Laminar flow can be induced by thermal fluctuations melting the crystal, but also by shear stress

  10. Resuspension onset and crater erosion by a vortex ring interacting with a particle layer

    E-Print Network [OSTI]

    Dalziel, Stuart

    Resuspension onset and crater erosion by a vortex ring interacting with a particle layer N. Bethke. Fluids 24, 055106 (2012) Conveyor belt effect in the flow through a tube of a viscous fluid with spinning and crater erosion by a vortex ring interacting with a particle layer N. Bethkea) and S. B. Dalziel

  11. Mixing characteristics of compressible vortex rings interacting with normal shock waves

    SciTech Connect (OSTI)

    Cetegen, B.M. . Mechanical Engineering Dept.); Hermanson, J.C. )

    1995-01-01

    Current interest in the interaction between compressible vortical flows and shock waves is largely motivated by the need to promote rapid, loss-effective mixing and combustion of hydrogen and hydrocarbon fuels for supersonic combustor applications. The instability mechanisms and mixing enhancement arising from the interaction of a compressible vortex ring with a normal shock wave were studied in a colinear, dual-shock tube. This flow geometry simulates features of the interaction of a shock wave with a jet containing streamwise vorticity, a configuration of significant interest for supersonic combustion applications. Flow visualization and quantitative concentration measurements were performed by planar laser Rayleigh scattering. For a given primary shock strength, interfacial instability is more evident in a weak vortex ring than in a strong vortex ring. In all cases, the identity of the vortex ring is lost after a sufficiently long time of interaction. The probability density function of the mixed fluid changes rapidly from a bimodal distribution to a single peak upon processing by a shock wave. The most probable concentration decreases with time, indicating a rapid increase in mixing and dilution of the vortex fluid. The mixing enhancement is most rapid for the case of a strong vortex ring interacting with a strong shock wave, somewhat slower for a weak vortex ring and a strong shock wave, and significantly slower for the case of a strong vortex ring and a weaker shock wave. These observations are consistent with the earlier numerical predictions.

  12. Comparison of optical vortex detection methods for use with a Shack-Hartmann

    E-Print Network [OSTI]

    Dainty, Chris

    Comparison of optical vortex detection methods for use with a Shack-Hartmann wavefront sensor Kevin of de- tecting optical vortices from Shack-Hartmann wavefront sensor (SHWFS) data, the vortex potential of Shack-Hartmann wavefront sensing," J. Refract. Surg. 17, S573­S577 (2001). 13. J. Notaras and C

  13. Numerical Simulation of Vortex Pyrolysis Reactors for Condensable Tar Production from Biomass

    E-Print Network [OSTI]

    Miller, Richard S.

    Numerical Simulation of Vortex Pyrolysis Reactors for Condensable Tar Production from Biomass R. S is performed in order to evaluate the performance and optimal operating conditions of vortex pyrolysis reactors particle pyrolysis is coupled with a compressible Reynolds stress transport model for the turbulent reactor

  14. Nanogenerator as an active sensor for vortex capture and ambient wind-velocity detection

    E-Print Network [OSTI]

    Wang, Zhong L.

    efficiently convert the vortex motion in the atmosphere into electricity. Based on the Karman vortex street in wireless environmental monitoring networks. 1. Introduction Self-powered nanosystem is a promising concept for the realization of environmental wireless sensor networks. Due to the enormous demands of distributed nodes

  15. The critical velocity for vortex existence in a two dimensional rotating Bose-Einstein condensate

    E-Print Network [OSTI]

    Ignat, Radu

    The critical velocity for vortex existence in a two dimensional rotating Bose-Einstein condensate-Einstein condensate. It consists in minimizing a Gross-Pitaevskii functional defined in R2 under the unit mass constraint. We estimate the critical rotational speed 1 for vortex existence in the bulk of the condensate

  16. Generalized London free energy for high-Tc vortex lattices Ian Affleck

    E-Print Network [OSTI]

    Franz, Marcel

    Generalized London free energy for high-Tc vortex lattices Ian Affleck Department of Physics-1829 97 50402-4 The London free energy provides a very simple way of studying the vortex lattice that this effect can arise from additional quartic derivative terms in the Ginzburg-Landau GL free energy4­7 or

  17. A model for universal time scale of vortex ring formation Kamran Mohseni

    E-Print Network [OSTI]

    Mohseni, Kamran

    and Applied Science, 104-44, California Institute of Technology, Pasadena, California 91125 Morteza Gharib Graduate Aeronautical Laboratory, California Institute of Technology, Pasadena, California 91125 Received of the fluid out of the cylinder and the approximation of the vortex at the pinch off moment by a vortex

  18. Modeling bubble-vortex interactions Modeling and simulation of multiple bubble entrainment and interactions with two

    E-Print Network [OSTI]

    Apte, Sourabh V.

    Modeling bubble-vortex interactions Modeling and simulation of multiple bubble entrainment entrainment and interactions with two dimensional vorti- cal flows are preformed using a Discrete Element microbubbles entrained in a traveling vortex tube is studied in detail. The test case resembles the experiments

  19. Electronic states near a quantum fluctuating point vortex in a d-wave superconductor: Dirac fermion theory

    E-Print Network [OSTI]

    -point motion in a d-wave superconductor. The vortex is treated as a point flux tube, carrying fluxElectronic states near a quantum fluctuating point vortex in a d-wave superconductor: Dirac fermion model of the low-energy electronic states in the vicinity of a vortex undergoing quantum zero

  20. Slowing of vortex rings by development of Kelvin waves Robert E. Hershberger, Diogo Bolster, and Russell J. Donnelly*

    E-Print Network [OSTI]

    Bolster, Diogo

    , at least for a straight vortex tube case, results from subjection to a straining field in a planeSlowing of vortex rings by development of Kelvin waves Robert E. Hershberger, Diogo Bolster the slowing of viscous vortex rings. In particular we do so using the concept of drag coefficient, which

  1. Bluff Body Flow Simulation Using a Vortex Element Method

    SciTech Connect (OSTI)

    Anthony Leonard; Phillippe Chatelain; Michael Rebel

    2004-09-30

    Heavy ground vehicles, especially those involved in long-haul freight transportation, consume a significant part of our nation's energy supply. it is therefore of utmost importance to improve their efficiency, both to reduce emissions and to decrease reliance on imported oil. At highway speeds, more than half of the power consumed by a typical semi truck goes into overcoming aerodynamic drag, a fraction which increases with speed and crosswind. Thanks to better tools and increased awareness, recent years have seen substantial aerodynamic improvements by the truck industry, such as tractor/trailer height matching, radiator area reduction, and swept fairings. However, there remains substantial room for improvement as understanding of turbulent fluid dynamics grows. The group's research effort focused on vortex particle methods, a novel approach for computational fluid dynamics (CFD). Where common CFD methods solve or model the Navier-Stokes equations on a grid which stretches from the truck surface outward, vortex particle methods solve the vorticity equation on a Lagrangian basis of smooth particles and do not require a grid. They worked to advance the state of the art in vortex particle methods, improving their ability to handle the complicated, high Reynolds number flow around heavy vehicles. Specific challenges that they have addressed include finding strategies to accurate capture vorticity generation and resultant forces at the truck wall, handling the aerodynamics of spinning bodies such as tires, application of the method to the GTS model, computation time reduction through improved integration methods, a closest point transform for particle method in complex geometrics, and work on large eddy simulation (LES) turbulence modeling.

  2. Gradient catastrophe and flutter in vortex filament dynamics

    E-Print Network [OSTI]

    B. G. Konopelchenko; G. Ortenzi

    2011-06-02

    Gradient catastrophe and flutter instability in the motion of vortex filament within the localized induction approximation are analyzed. It is shown that the origin if this phenomenon is in the gradient catastrophe for the dispersionless Da Rios system which describes motion of filament with slow varying curvature and torsion. Geometrically this catastrophe manifests as a rapid oscillation of a filament curve in a point that resembles the flutter of airfoils. Analytically it is the elliptic umbilic singularity in the terminology of the catastrophe theory. It is demonstrated that its double scaling regularization is governed by the Painlev\\'e-I equation.

  3. Vortex nozzle for segmenting and transporting metal chips from turning operations

    DOE Patents [OSTI]

    Bieg, L.F.

    1993-04-20

    Apparatus for collecting, segmenting and conveying metal chips from machining operations utilizes a compressed gas driven vortex nozzle for receiving the chip and twisting it to cause the chip to segment through the application of torsional forces to the chip. The vortex nozzle is open ended and generally tubular in shape with a converging inlet end, a constant diameter throat section and a diverging exhaust end. Compressed gas is discharged through angled vortex ports in the nozzle throat section to create vortex flow in the nozzle and through an annular inlet at the entrance to the converging inlet end to create suction at the nozzle inlet and cause ambient air to enter the nozzle. The vortex flow in the nozzle causes the metal chip to segment and the segments thus formed to pass out of the discharge end of the nozzle where they are collected, cleaned and compacted as needed.

  4. The Relation Between Dry Vortex Merger and Tropical Cyclone Genesis over the Atlantic Ocean

    SciTech Connect (OSTI)

    Chen, Shu-Hua; Liu, Yi-Chin

    2014-10-27

    A strong, convective African tropical disturbance has a greater chance to develop into a Tropical 23 Depression (TD) if it merges with a shallow, dry vortex (D-vortex) from the north of the African 24 easterly jet (AEJ) after leaving the western coast. Using 11-year reanalysis data we found that the 25 western tip of a vortex strip at northwestern Africa can serve as dry vortices for the D-vortex 26 merger if it shifts southward. Another source of D-vortices is the westward propagating lows 27 along the southern edge of the Saharan air. The D-vortex merger process occurred for 63.5% of 28 tropical cyclones (TCs) or developing systems over the main development region of the Atlantic 29 Ocean, while it occurred for 54% of non-developing systems. TC genesis could be largely 30 controlled by the large-scale environment, but the differences in characteristics of vortices 31 associated with the D-vortex merger between developing and non-developing systems could 32 potentially help determine their destinies; in general, developing systems were dominated by a 33 more intense and moist south vortex, while non-developing systems were dominated by a north 34 vortex which was more intense, drier, and larger in size. Analysis also shows that 74% of intense 35 developing systems were involved with the D-vortex merger process. More attention needs to be 36 paid to the D-vortex merger and the characteristics of those vortices as they can play significant 37 roles or have a strong indication in Atlantic TC genesis.

  5. Formation Flying and Deformable Instruments

    SciTech Connect (OSTI)

    Rio, Yvon

    2009-05-11

    Astronomers have always attempted to build very stable instruments. They fight all that can cause mechanical deformation or image motion. This has led to well established technologies (autoguide, active optics, thermal control, tip/tilt correction), as well as observing methods based on the use of controlled motion (scanning, micro scanning, shift and add, chopping and nodding). Formation flying disturbs this practice. It is neither possible to reduce the relative motion to very small amplitudes, nor to control it at will. Some impacts on Simbol-X instrument design, and operation are presented.

  6. Strategic Plan Core strategies

    E-Print Network [OSTI]

    Oxford, University of

    Strategic Plan 2013­18 Vision Priorities Core strategies Enabling strategies #12;Strategic Plan on the Strategic Plan, ensuring that it continues to meet academic needs, enables us to respond to the external the framework for making the Strategic Plan operational at divisional and service level. ©UniversityofOxford #12

  7. Venturi/vortex technology for controlling chromium electroplating emissions

    SciTech Connect (OSTI)

    Hay, K.J.; Northrup, J. [Army Construction Engineering Research Labs., Champaign, IL (United States); Heck, S.R. [MSE-HKM, Inc., Butte, MT (United States)

    1997-12-31

    A new technology has been developed to control air emissions from hexavalent chromium electroplating tanks. The venturi/vortex scrubber uses a patented drain assembly to pull plating solution, air with toxic particulates above the solution, and unpopped bubbles of generated gases down with a gravity generated vortex effect. The recirculated plating solution acts as the scrubbing liquid and air agitation is eliminated. Separated gases are passed through a condenser/filter to remove any remaining fumes. The device is almost entirely constructed of CPVC. This device offers several advantages over conventional end-of-pipe systems including significantly lower cost, no wastewater, no extensive ventilation system, and emissions are recycled. The system can be is easily retrofitted to existing tanks, however, a loose fitting tank lid is recommended. A pilot demonstration has been performed at Benet Laboratory, Watervliet, NY (US Army) with a 1,500 gallon chromic acid electroplating tank and 1,500 Amps of applied current. Overall chromium emissions results were 0.00002 mg/Amp-hr, surpassing the stringent California State requirement of 0.006 mg/Amp-hr. Emission prevention by capturing unpopped bubbles is the method in which this system reduces the most emissions. The system met current ambient worker safety standards. Two major improvements are recommended: an increase in gas flow rate through the system and a solution to the system`s sensitivity to the plating solution level.

  8. The deformed exponential functions of two variables

    E-Print Network [OSTI]

    Stankovi?, Miomir S; Rajkovi?, Predrag M

    2010-01-01

    In the recent development in a various disciplines of physics, it is noted the need for including the deformed versions of the exponential functions. In this paper, we consider the deformations which have two purposes: to have them like special cases, and, even more, to acquit their inauguration from mathematical point of view. Really, we will show interesting differential and difference properties of our deformations which are important in forming and explanation of continuous and discrete models of numerous phenomena.

  9. MECHANICAL MODELS FOR INTERSEISMIC DEFORMATION IN

    E-Print Network [OSTI]

    Kanda, Ravi

    MECHANICAL MODELS FOR INTERSEISMIC DEFORMATION IN SUBDUCTION ZONES Thesis by Ravi V. S. Kanda that mechanical coupling on such asperities alone is sufficient to explain currently available geodetic

  10. Deformed Geometric Algebra and Supersymmetric Quantum Mechanics

    E-Print Network [OSTI]

    Peter Henselder

    2006-09-09

    Deforming the algebraic structure of geometric algebra on the phase space with a Moyal product leads naturally to supersymmetric quantum mechanics in the star product formalism.

  11. Higher Order Deformations of Complex Structures

    E-Print Network [OSTI]

    Eric D'Hoker; Duong H. Phong

    2015-06-23

    Deformations of complex structures by finite Beltrami differentials are considered on general Riemann surfaces. Exact formulas to any fixed order are derived for the corresponding deformations of the period matrix, Green's functions, and correlation functions in conformal field theories with vanishing total central charge. The stress tensor is shown to give a simple representation of these deformations valid to all orders. Such deformation formulas naturally enter into the evaluation of superstring amplitudes at two-loop order with Ramond punctures, and at higher loop order, in the supergravity formulation of the RNS superstring.

  12. Higher Order Deformations of Complex Structures

    E-Print Network [OSTI]

    D'Hoker, Eric

    2015-01-01

    Deformations of complex structures by finite Beltrami differentials are considered on general Riemann surfaces. Exact formulas to any fixed order are derived for the corresponding deformations of the period matrix, Green's functions, and correlation functions in conformal field theories with vanishing total central charge. The stress tensor is shown to give a simple representation of these deformations valid to all orders. Such deformation formulas naturally enter into the evaluation of superstring amplitudes at two-loop order with Ramond punctures, and at higher loop order, in the supergravity formulation of the RNS superstring.

  13. Improving Preclinical Testing of Deformity Correction Surgery

    E-Print Network [OSTI]

    Borkowski, Sean Leo

    2015-01-01

    permit subsequent testing. ” In other words, non-destructivenon-destructive and do not cause plastic deformation of the intervening tissues or spine structure, thus allowing repeated testing,

  14. 2012 ROCK DEFORMATION: FEEDBACK PROCESSES IN ROCK DEFORMATION GORDON RESEARCH CONFERENCE, AUGUST 19-24, 2012

    SciTech Connect (OSTI)

    Kelemen, Peter

    2012-08-24

    Topics covered include: Failure At High Confining Pressure; Fluid-assisted Slip, Earthquakes & Fracture; Reaction-driven Cracking; Fluid Transport, Deformation And Reaction; Localized Fluid Transport And Deformation; Earthquake Mechanisms; Subduction Zone Dynamics And Crustal Growth.

  15. Illusionist: Transforming Lightweight Cores into Aggressive Cores on Demand

    E-Print Network [OSTI]

    Torrellas, Josep

    Illusionist: Transforming Lightweight Cores into Aggressive Cores on Demand HPCA-19 February 27;Adapting to Application Demands Number of threads to execute is not constant o Many threads available

  16. FEM Analysis ofFEM Analysis of Deformation and Fracture ofDeformation and Fracture of

    E-Print Network [OSTI]

    Grujicic, Mica

    FEM Analysis ofFEM Analysis of Deformation and Fracture ofDeformation and Fracture of Deformation and Fracture in Polycrystalline -TiAl + 2-Ti3Al Single Crystals #12;Use of -TiAl + 2-Ti3Al Alloys-Temperature Ductility ·Low Ambient-Temperature Fracture Toughness (KIC

  17. Large Mesh Deformation Using the Volumetric Graph Laplacian

    E-Print Network [OSTI]

    Kazhdan, Michael

    Large Mesh Deformation Using the Volumetric Graph Laplacian Kun Zhou1 Jin Huang2 John Snyder3 Related Work Deformation on Volumetric Graphs Deformation from 2D curves Results Conclusions #12;11/21/2007 Bhaskar Kishore 3 Outline Introduction Related Work Deformation on Volumetric Graphs Deformation from

  18. Electromagnetic pump stator core

    DOE Patents [OSTI]

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

    1995-01-17

    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.

  19. Disturbed core Undisturbed soil

    E-Print Network [OSTI]

    Pennycook, Steve

    Batch Disturbed core Undisturbed soil column Pedon Field Watershed Multi-scale modeling .001-1 m3 1-10 m3 10-10,000 m3 >10,000 m3 Unraveling the influence of scale on organic C transport Soil through deep soil profiles may be the "missing" C flux in global budgets. Jardine, P.M., M.A. Mayes, J. R

  20. Banded electromagnetic stator core

    DOE Patents [OSTI]

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

    1994-04-05

    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, Alan W. (San Jose, CA); Gonzales, Aaron A. (San Jose, CA); Patel, Mahadeo R. (San Jose, CA); Olich, Eugene E. (Aptos, CA)

    1994-01-01

    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.

  2. Banded electromagnetic stator core

    DOE Patents [OSTI]

    Fanning, Alan W. (San Jose, CA); Gonzales, Aaron A. (San Jose, CA); Patel, Mahadeo R. (San Jose, CA); Olich, Eugene E. (Aptos, CA)

    1996-01-01

    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.

  3. Variable depth core sampler

    DOE Patents [OSTI]

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

    1996-02-20

    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.

  4. Variable depth core sampler

    DOE Patents [OSTI]

    Bourgeois, Peter M. (Hamburg, NY); Reger, Robert J. (Grand Island, NY)

    1996-01-01

    A variable depth core sampler apparatus 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.

  5. Decay of helical Kelvin waves on a quantum vortex filament

    SciTech Connect (OSTI)

    Van Gorder, Robert A.

    2014-07-15

    We study the dynamics of helical Kelvin waves moving along a quantum vortex filament driven by a normal fluid flow. We employ the vector form of the quantum local induction approximation (LIA) due to Schwarz. For an isolated filament, this is an adequate approximation to the full Hall-Vinen-Bekarevich-Khalatnikov dynamics. The motion of such Kelvin waves is both translational (along the quantum vortex filament) and rotational (in the plane orthogonal to the reference axis). We first present an exact closed form solution for the motion of these Kelvin waves in the case of a constant amplitude helix. Such solutions exist for a critical wave number and correspond exactly to the Donnelly-Glaberson instability, so perturbations of such solutions either decay to line filaments or blow-up. This leads us to consider helical Kelvin waves which decay to line filaments. Unlike in the case of constant amplitude helical solutions, the dynamics are much more complicated for the decaying helical waves, owing to the fact that the rate of decay of the helical perturbations along the vortex filament is not constant in time. We give an analytical and numerical description of the motion of decaying helical Kelvin waves, from which we are able to ascertain the influence of the physical parameters on the decay, translational motion along the filament, and rotational motion, of these waves (all of which depend nonlinearly on time). One interesting finding is that the helical Kelvin waves do not decay uniformly. Rather, such waves decay slowly for small time scales, and more rapidly for large time scales. The rotational and translational velocity of the Kelvin waves depend strongly on this rate of decay, and we find that the speed of propagation of a helical Kelvin wave along a quantum filament is large for small time while the wave asymptotically slows as it decays. The rotational velocity of such Kelvin waves along the filament will increase over time, asymptotically reaching a finite value. These decaying Kelvin waves correspond to wave number below the critical value for the Donnelly-Glaberson instability, and hence our results on the Schwarz quantum LIA correspond exactly to what one would expect from prior work on the Donnelly-Glaberson instability.

  6. A Painting Interface for Interactive Surface Deformations

    E-Print Network [OSTI]

    A Painting Interface for Interactive Surface Deformations Jason Lawrence a Thomas Funkhouser a a with a painting interface that gives the user direct, local control over a physical simulation. The "paint" a user- locity, the user can effect surface deformations. We have found that this painting metaphor gives

  7. INTRODUCTION TO THE CORE CURRICULUM

    E-Print Network [OSTI]

    Schrag, Daniel

    1 INTRODUCTION TO THE CORE CURRICULUM The purpose of this guide is to inform members of the Freshman class about Harvard's Core Curriculum. It explains the aims and design of the program, offers some of concentration. I The Core Curriculum for undergraduate education at Harvard is both a requirement

  8. Vortex flow in the technology of radiation wave cracking (RWC)

    E-Print Network [OSTI]

    L. A. Tsoy; V. N. Kolushov; A. G. Komarov; A. N. Tsoy

    2012-09-16

    This article examines the theory of vortex flows in relation to the processes occurring in the radiation-wave cracking of crude oil, when the crude oil is sprayed into the gas stream in the form of a mist and then is fed into the reactor, where it is treated by the accelerated electrons and the UHF radiation. The output of this process are the products with the specified parameters (high-octane petroleum products). This process operates at the ambient pressure and temperature, which makes the process safer for industrial purposes. Besides the process itself, the authors described the equipment used in this process, as well as the parameters of the optimal process.

  9. Stabilization of three-wave vortex beams in the waveguide

    E-Print Network [OSTI]

    Gammal, Arnaldo

    2015-01-01

    We consider two-dimensional (2D) localized vortical modes in the three-wave system with the quadratic ($\\chi ^{(2)}$) nonlinearity, alias nondegenerate second-harmonic-generating system, guided by the isotropic harmonic-oscillator (HO) (alias parabolic) confining potential. In addition to the straightforward realization in optics, the system models mixed atomic-molecular Bose-Einstein condensates (BECs). The main issue is stability of the vortex modes, which is investigated through computation of instability growth rates for eigenmodes of small perturbations, and by means of direct simulations. The threshold of parametric instability for single-color beams, represented solely by the second harmonic (SH) with zero vorticity, is found in an analytical form with the help of the variational approximation (VA). Trapped states with vorticities $\\left( +1,-1,0\\right) $ in the two fundamental-frequency (FF) components and the SH one [the so-called \\textit{hidden-vorticity} (HV) modes] are completely unstable. Also un...

  10. Energy harvesting using vortex-induced vibrations of tensioned cables

    E-Print Network [OSTI]

    Grouthier, Clement; de Langre, Emmanuel

    2012-01-01

    The development of energy harvesting systems based on fluid/structure interactions is part of the global search for innovative tools to produce renewable energy. In this paper, the possibility to harvest energy from a flow using vortex-induced vibrations (VIV) of a tensioned flexible cable is analyzed. The fluid loading on the vibrating solid and resulting dynamics are computed using an appropriate wake-oscillator model, allowing one to perform a systematic parametric study of the efficiency. The generic case of an elastically-mounted rigid cylinder is first investigated, before considering an infinite cable with two different types of energy harvesting : a uniformly spanwise distributed harvesting and then a periodic distribution of discrete harvesting devices. The maximum harvesting efficiency is of the same order for each configuration and is always reached when the solid body and its wake are in a frequency lock-in state.

  11. Fast chirality reversal of the magnetic vortex by electric current

    SciTech Connect (OSTI)

    Lim, W. L. Liu, R. H.; Urazhdin, S.; Tyliszczak, T.; Erokhin, S. G.; Berkov, D.

    2014-12-01

    The possibility of high-density information encoding in magnetic materials by topologically stable inhomogeneous magnetization configurations such as domain walls, skyrmions, and vortices has motivated intense research into mechanisms enabling their control and detection. While the uniform magnetization states can be efficiently controlled by electric current using magnetic multilayer structures, this approach has proven much more difficult to implement for inhomogeneous states. Here, we report direct observation of fast reversal of magnetic vortex by electric current in a simple planar structure based on a bilayer of spin Hall material Pt with a single microscopic ferromagnetic disk contacted by asymmetric electrodes. The reversal is enabled by a combination of the chiral Oersted field and spin current generated by the nonuniform current distribution in Pt. Our results provide a route for the efficient control of inhomogeneous magnetization configurations by electric current.

  12. Gas turbine engine combustor can with trapped vortex cavity

    DOE Patents [OSTI]

    Burrus, David Louis; Joshi, Narendra Digamber; Haynes, Joel Meier; Feitelberg, Alan S.

    2005-10-04

    A gas turbine engine combustor can downstream of a pre-mixer has a pre-mixer flowpath therein and circumferentially spaced apart swirling vanes disposed across the pre-mixer flowpath. A primary fuel injector is positioned for injecting fuel into the pre-mixer flowpath. A combustion chamber surrounded by an annular combustor liner disposed in supply flow communication with the pre-mixer. An annular trapped dual vortex cavity located at an upstream end of the combustor liner is defined between an annular aft wall, an annular forward wall, and a circular radially outer wall formed therebetween. A cavity opening at a radially inner end of the cavity is spaced apart from the radially outer wall. Air injection first holes are disposed through the forward wall and air injection second holes are disposed through the aft wall. Fuel injection holes are disposed through at least one of the forward and aft walls.

  13. Real-time Volumetric Deformable Models for Surgery Simulation using

    E-Print Network [OSTI]

    Real-time Volumetric Deformable Models for Surgery Simulation using Finite Elements volumetric Finite Element models to surgery simulation. In particular it presents three new approaches: Virtual Surgery, Real-Time Deformation, Solid Volumetric Deformable Mod- els, Virtual Reality, Finite

  14. Vortex Induced Vibrations of cylinders : experiments in reducing drag force and amplitude of motion

    E-Print Network [OSTI]

    Farrell, David Emmanuel

    2007-01-01

    Reducing the deleterious effect of Vortex Induced Vibrations (VIV) in marine risers is an important task for ocean engineers; and many competing factors exist in the design of VIV suppression devices. This thesis explores ...

  15. Numerically-based ducted propeller design using vortex lattice lifting line theory

    E-Print Network [OSTI]

    Stubblefield, John M

    2008-01-01

    This thesis used vortex lattice lifting line theory to model an axisymmetrical-ducted propeller with no gap between the duct and the propeller. The theory required to model the duct and its interaction with the propeller ...

  16. Effects of trailing edge flap dynamic deployment on blade-vortex interactions 

    E-Print Network [OSTI]

    Nelson, Carter T.

    1997-01-01

    A theoretical and experimental investigation is undertaken to determine the effects of an actively deployable trailing edge flap on the disturbances created during blade-vortex interactions (BVI). The theoretical model consists of an unsteady panel...

  17. An adaptive mesh method for the simulation of Blade Vortex Interaction 

    E-Print Network [OSTI]

    Kim, Kyu-Sup

    1998-01-01

    An adaptive mesh method for the simulation of parallel ics. Blade Vortex Interaction (BV1) with an active Trailing Edge Flap (TEF) is presented. The two-dimensional 1111-steady problem is solved by a higher order upwind Euler method...

  18. Variability of the polar stratospheric vortex and its impact on surface climate patterns

    E-Print Network [OSTI]

    Sheshadri, Aditi

    2015-01-01

    This thesis investigates various aspects of the variability of the stratospheric polar vortex and the effect of this variability on tropospheric weather and climate patterns on various timescales. In the first part of this ...

  19. Reduced gravity rankine cycle design and optimization with passive vortex phase separation 

    E-Print Network [OSTI]

    Supak, Kevin Robert

    2009-05-15

    turbo machinery, require kilowatts of power and are untested for high vapor flow conditions. The Interphase Transport Phenomena (ITP) laboratory has developed a low-power, passive microgravity vortex phase separator (MVS) which has already proven...

  20. Effect of traveling waves on Vortex-Induced Vibration of long flexible cylinders

    E-Print Network [OSTI]

    Jaiswal, Vivek, Ph. D. Massachusetts Institute of Technology

    2009-01-01

    Offshore marine risers and pipelines, exposed to ocean currents, are susceptible to Vortex-Induced Vibration (VIV). Accurate prediction of VIV is necessary for estimating the fatigue life as well as for taking corrective ...

  1. Vortex-induced vibration of flexible cylinders in time-varying flows

    E-Print Network [OSTI]

    Resvanis, Themistocles L

    2014-01-01

    This thesis investigates two aspects of Vortex-Induced Vibrations (VIV) on long flexible cylinders. The work is split into a minor and major part. The minor part addresses the effect of Reynolds number on flexible cylinder ...

  2. Enhancement of vortex induced forces and motion through surface roughness control

    DOE Patents [OSTI]

    Bernitsas, Michael M. (Saline, MI); Raghavan, Kamaldev (Houston, TX)

    2011-11-01

    Roughness is added to the surface of a bluff body in a relative motion with respect to a fluid. The amount, size, and distribution of roughness on the body surface is controlled passively or actively to modify the flow around the body and subsequently the Vortex Induced Forces and Motion (VIFM). The added roughness, when designed and implemented appropriately, affects in a predetermined way the boundary layer, the separation of the boundary layer, the level of turbulence, the wake, the drag and lift forces, and consequently the Vortex Induced Motion (VIM), and the fluid-structure interaction. The goal of surface roughness control is to increase Vortex Induced Forces and Motion. Enhancement is needed in such applications as harnessing of clean and renewable energy from ocean/river currents using the ocean energy converter VIVACE (Vortex Induced Vibration for Aquatic Clean Energy).

  3. Lagrangian analysis of fluid transport in empirical vortex ring flows Shawn C. Shadden

    E-Print Network [OSTI]

    Marsden, Jerrold

    Lagrangian analysis of fluid transport in empirical vortex ring flows Shawn C. Shadden Control and Dynamical Systems, California Institute of Technology, Pasadena, California 91125 John O. Dabiri Graduate Aeronautical Laboratories and Bioengineering, California Institute of Technology, Pasadena, California 91125

  4. Core-Collapse Supernovae

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News PublicationsAuditsClusterInformationContract Managementthermoelectric powerTheCore

  5. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments? WeDatastreamstps DocumentationAtlanticENAField ParticipantsField Campaign StatisticsPastIce Cores

  6. Modeling fluid flow in deformation bands with stabilized localization...

    Office of Scientific and Technical Information (OSTI)

    Modeling fluid flow in deformation bands with stabilized localization mixed finite elements. Citation Details In-Document Search Title: Modeling fluid flow in deformation bands...

  7. First Generation Advanced High-Strength Steels Deformation Fundamental...

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

    Generation Advanced High-Strength Steels Deformation Fundamentals First Generation Advanced High-Strength Steels Deformation Fundamentals 2012 DOE Hydrogen and Fuel Cells Program...

  8. STATISTICAL MECHANICS MODELING OF MESOSCALE DEFORMATION IN METALS...

    Office of Scientific and Technical Information (OSTI)

    STATISTICAL MECHANICS MODELING OF MESOSCALE DEFORMATION IN METALS Anter El-Azab 36 MATERIALS SCIENCE dislocation dynamics; mesoscale deformation of metals; crystal mechanics...

  9. Deformation mechanisms in a ferritic superalloy revealed by in...

    Office of Scientific and Technical Information (OSTI)

    Deformation mechanisms in a ferritic superalloy revealed by in situ neutron diffraction studies at elevated temperatures Citation Details In-Document Search Title: Deformation...

  10. Explicit mean-field radius for nearly parallel vortex filaments in statistical equilibrium

    E-Print Network [OSTI]

    Timothy D. Andersen; Chjan C. Lim

    2006-11-19

    Geophysical research has focused on flows, such as ocean currents, as two dimensional. Two dimensional point or blob vortex models have the advantage of having a Hamiltonian, whereas 3D vortex filament or tube systems do not necessarily have one, although they do have action functionals. On the other hand, certain classes of 3D vortex models called nearly parallel vortex filament models do have a Hamiltonian and are more accurate descriptions of geophysical and atmospheric flows than purely 2D models, especially at smaller scales. In these ``quasi-2D'' models we replace 2D point vortices with vortex filaments that are very straight and nearly parallel but have Brownian variations along their lengths due to local self-induction. When very straight, quasi-2D filaments are expected to have virtually the same planar density distributions as 2D models. An open problem is when quasi-2D model statistics behave differently than those of the related 2D system and how this difference is manifested. In this paper we study the nearly parallel vortex filament model of Klein, Majda, Damodaran in statistical equilibrium. We are able to obtain a free-energy functional for the system in a non-extensive thermodynamic limit that is a function of the mean square vortex position $R^2$ and solve \\emph{explicitly} for $R^2$. Such an explicit formula has never been obtained for a non-2D model. We compare the results of our formula to a 2-D formula of \\cite{Lim:2005} and show qualitatively different behavior even when we disallow vortex braiding. We further confirm our results using Path Integral Monte Carlo (Ceperley (1995)) \\emph{without} permutations and that the Klein, Majda, Damodaran model's asymptotic assumptions \\emph{are valid} for parameters where these deviations occur.

  11. Vortex in a weakly relativistic Bose gas at zero temperature and relativistic fluid approximation

    E-Print Network [OSTI]

    B. Boisseau

    2004-09-14

    The Bogoliubov procedure in quantum field theory is used to describe a relativistic almost ideal Bose gas at zero temperature. Special attention is given to the study of a vortex. The radius of the vortex in the field description is compared to that obtained in the relativistic fluid approximation. The Kelvin waves are studied and, for long wavelengths, the dispersion relation is obtained by an asymptotic matching method and compared with the non relativistic result.

  12. Investigation of Vortex Structures in Gas-Discharge Nonneutral Electron Plasma: III. Pulse Ejection of Electrons at the Formation and Radial Oscillations of Vortex Structure

    E-Print Network [OSTI]

    Kervalishvili, N A

    2015-01-01

    The results of experimental investigations of electron ejection from gas-discharge nonneutral electron plasma at the formation and radial oscillations of vortex structure have been presented. The electrons are injected from the vortex structure and the adjacent region of electron sheath in the form of pulses the duration and periodicity of which are determined by the processes of evolution and dynamics of this structure. The possible mechanisms of pulse ejection of electrons are considered. The influence of electron ejection on other processes in discharge electron sheath is analyzed.

  13. Deformation of Silica Aerogel During Fluid Adsorption

    E-Print Network [OSTI]

    Tobias Herman; James Day; John Beamish

    2005-06-30

    Aerogels are very compliant materials - even small stresses can lead to large deformations. In this paper we present measurements of the linear deformation of high porosity aerogels during adsorption of low surface tension fluids, performed using a Linear Variable Differential Transformer (LVDT). We show that the degree of deformation of the aerogel during capillary condensation scales with the surface tension, and extract the bulk modulus of the gel from the data. Furthermore we suggest limits on safe temperatures for filling and emptying low density aerogels with helium.

  14. Supersymmetric Deformations of Maximally Supersymmetric Gauge Theories

    E-Print Network [OSTI]

    M. Movshev; A. Schwarz

    2012-06-19

    We study supersymmetric and super Poincar\\'e invariant deformations of ten-dimensional super Yang-Mills theory and of its dimensional reductions. We describe all infinitesimal super Poincar\\'e invariant deformations of equations of motion of ten-dimensional super Yang-Mills theory and its reduction to a point; we discuss the extension of them to formal deformations. Our methods are based on homological algebra, in particular, on the theory of L-infinity and A-infinity algebras. The exposition of this theory as well as of some basic facts about Lie algebra homology and Hochschild homology is given in appendices.

  15. Deformable contours Slides from Prof. Kristen Grauman

    E-Print Network [OSTI]

    Kosecka, Jana

    ;Deformable contours a.k.a. active contours, snakes Given: initial contour (model) near desired object [Snakes contours Given: initial contour (model) near desired object a.k.a. active contours, snakes Figure credit

  16. MEMS deformable mirror CubeSat testbed

    E-Print Network [OSTI]

    Marinan, Anne D.

    To meet the high contrast requirement of 1 × 10[superscript ?10] to image an Earth-like planet around a Sun-like star, space telescopes equipped with coronagraphs require wavefront control systems. Deformable mirrors are ...

  17. Probing deformed commutators with macroscopic harmonic oscillators

    E-Print Network [OSTI]

    Mateusz Bawaj; Ciro Biancofiore; Michele Bonaldi; Federica Bonfigli; Antonio Borrielli; Giovanni Di Giuseppe; Lorenzo Marconi; Francesco Marino; Riccardo Natali; Antonio Pontin; Giovanni A. Prodi; Enrico Serra; David Vitali; Francesco Marin

    2015-08-25

    A minimal observable length is a common feature of theories that aim to merge quantum physics and gravity. Quantum mechanically, this concept is associated to a nonzero minimal uncertainty in position measurements, which is encoded in deformed commutation relations. In spite of increasing theoretical interest, the subject suffers from the complete lack of dedicated experiments and bounds to the deformation parameters are roughly extrapolated from indirect measurements. As recently proposed, low-energy mechanical oscillators could allow to reveal the effect of a modified commutator. Here we analyze the free evolution of high quality factor micro- and nano-oscillators, spanning a wide range of masses around the Planck mass $m_{\\mathrm{P}}$ (${\\approx 22\\,\\mu\\mathrm{g}}$), and compare it with a model of deformed dynamics. Previous limits to the parameters quantifying the commutator deformation are substantially lowered.

  18. HTTF Core Stress Analysis

    SciTech Connect (OSTI)

    Brian D. Hawkes; Richard Schultz

    2012-07-01

    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.

  19. Influence of plastic deformation on bimaterial fault rupture directivity

    E-Print Network [OSTI]

    Dmowska, Renata

    Influence of plastic deformation on bimaterial fault rupture directivity Nora DeDontney,1 Elizabeth of the role of the stress state on the distribution of plastic deformation and the direction of preferred in determining the location of plastic deformation. For different orientations, plastic deformation can

  20. Large Deformation of Nitinol Under Shear Dominant Loading

    E-Print Network [OSTI]

    Daly, Samantha

    Large Deformation of Nitinol Under Shear Dominant Loading S. Daly & D. Rittel & K. Bhattacharya & G in Nitinol under large shear- dominated deformation are presented. To achieve a shear- dominated deformation transformation that is seen in uniaxial testing. The shear-dominant deformation of Nitinol in the plastic regime

  1. Ferromagnetic and antiferromagnetic order in bacterial vortex lattices

    E-Print Network [OSTI]

    Hugo Wioland; Francis G. Woodhouse; Jörn Dunkel; Raymond E. Goldstein

    2015-11-16

    Despite their inherent non-equilibrium nature, living systems can self-organize in highly ordered collective states that share striking similarities with the thermodynamic equilibrium phases of conventional condensed matter and fluid systems. Examples range from the liquid-crystal-like arrangements of bacterial colonies, microbial suspensions and tissues to the coherent macro-scale dynamics in schools of fish and flocks of birds. Yet, the generic mathematical principles that govern the emergence of structure in such artificial and biological systems are elusive. It is not clear when, or even whether, well-established theoretical concepts describing universal thermostatistics of equilibrium systems can capture and classify ordered states of living matter. Here, we connect these two previously disparate regimes: Through microfluidic experiments and mathematical modelling, we demonstrate that lattices of hydrodynamically coupled bacterial vortices can spontaneously organize into distinct phases of ferro- and antiferromagnetic order. The preferred phase can be controlled by tuning the vortex coupling through changes of the inter-cavity gap widths. The emergence of opposing order regimes is tightly linked to the existence of geometry-induced edge currents, reminiscent of those in quantum systems. Our experimental observations can be rationalized in terms of a generic lattice field theory, suggesting that bacterial spin networks belong to the same universality class as a wide range of equilibrium systems.

  2. Magnetorotational instability, current relaxation, and current-vortex sheet

    SciTech Connect (OSTI)

    Silveira, F. E. M. [Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Rua Santa Adélia, 166, CEP 09210-170, Bairro Bangu, Santo André, SP (Brazil)] [Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Rua Santa Adélia, 166, CEP 09210-170, Bairro Bangu, Santo André, SP (Brazil); Galvão, R. M. O. [Instituto de Física, Universidade de São Paulo, Rua do Matão, Travessa R, 187, CEP 05508-090, Cidade Universitária, São Paulo, SP (Brazil)] [Instituto de Física, Universidade de São Paulo, Rua do Matão, Travessa R, 187, CEP 05508-090, Cidade Universitária, São Paulo, SP (Brazil)

    2013-08-15

    The conjugate effect of current relaxation and of current-vortex sheet formation on the magnetorotational instability is explored in a conducting fluid. It is found that the relative amplification of the magnetic viscosity from marginal stability to the instability determined by the maximum growth rate is around 924% when resistive effects dominate, while the corresponding quantity is around 220% in the ideal limit. This shows that the conjugate influence is much more efficient to amplify the magnetic viscosity than just the effect due to the standard magnetic tension. It is also found that the magnitude of the magnetic viscosity is effectively enhanced by the conjugate influence. The results presented here may contribute to the understanding of the various processes that play a significant role in the mechanism of anomalous viscosity observed in Keplerian disks. It is argued that the new effect shall be relevant in thin accretion disks. It is also mentioned that the proposed formulation may be of interest for some theories of magnetic reconnection. Possible extensions of this work are suggested.

  3. Boundary effects on Zircaloy-4 cladding deformation in LOCA simulation tests. [PWR; BWR

    SciTech Connect (OSTI)

    Longest, A.W.; Chapman, R.H.; Crowley, J.L.

    1982-01-01

    Deformation behavior of Zircaloy-4 cladding under simulated loss-of-coolant accident (LOCA) conditions is being investigated in the Multirod Burst Test (MRBT) program in single rod and multirod tests. In these tests, internally-pressurized unirradiated Zircaloy-4 tubes containing internal electrical heaters are heated to failure in a low-pressure, superheated-steam environment (200 < Re < 800). The results provide a data base for evaluating deformation and blockage models employed with design-basis accident sequences to assess LWR core coolability for licensing purposes. Results of a recent 8 X 8 test indicate that models derived from smaller test arrays may not be representative of the behavior in large arrays, particularly for those temperature ranges in which large deformation can be expected. Two MRBT LOCA simulation tests conducted under the same nominal conditions (approx. 10 K/s heating rate from approx. 340/sup 0/C to failure at approx. 770/sup 0/C) were examined to determine the effects of array size and boundary conditions on deformation.

  4. Deforming convex RP3-structures on 3-orbifolds Deforming convex RP3-structures on 3-orbifolds

    E-Print Network [OSTI]

    Choi, Suhyoung

    Deforming convex RP3-structures on 3-orbifolds Deforming convex RP3-structures on 3-orbifolds-structures on 3-orbifolds Introduction Orbifolds and RPn-structures Orbifolds By an n-dimensional orbifold . an inclusion Uj Ui induces an equivariant map ~Uj ~Ui with respect to Gj Gi . A RPn-structure on an orbifold

  5. Deforming convex RP3-structures on 3-orbifolds Deforming convex RP3-structures on 3-orbifolds

    E-Print Network [OSTI]

    Choi, Suhyoung

    Deforming convex RP3-structures on 3-orbifolds Deforming convex RP3-structures on 3-orbifolds-structures on 3-orbifolds Outline A RPn-structure (projectively flat structure; real projective structure; projective structure) on an orbifold is a geometric structure on the orbifold modelled on (RPn, PGL(n + 1, R

  6. A Robust Numerical Method for Integration of Point-Vortex Trajectories in Two Dimensions

    E-Print Network [OSTI]

    Spencer A. Smith; Bruce M. Boghosian

    2010-11-19

    The venerable 2D point-vortex model plays an important role as a simplified version of many disparate physical systems, including superfluids, Bose-Einstein condensates, certain plasma configurations, and inviscid turbulence. This system is also a veritable mathematical playground, touching upon many different disciplines from topology to dynamic systems theory. Point-vortex dynamics are described by a relatively simple system of nonlinear ODEs which can easily be integrated numerically using an appropriate adaptive time stepping method. As the separation between a pair of vortices relative to all other inter-vortex length scales decreases, however, the computational time required diverges. Accuracy is usually the most discouraging casualty when trying to account for such vortex motion, though the varying energy of this ostensibly Hamiltonian system is a potentially more serious problem. We solve these problems by a series of coordinate transformations: We first transform to action-angle coordinates, which, to lowest order, treat the close pair as a single vortex amongst all others with an internal degree of freedom. We next, and most importantly, apply Lie transform perturbation theory to remove the higher-order correction terms in succession. The overall transformation drastically increases the numerical efficiency and ensures that the total energy remains constant to high accuracy.

  7. Transition between vortex rings and MAP solutions for electrically charged magnetic solutions

    SciTech Connect (OSTI)

    Wong, Khai-Ming; Soltanian, Amin; Teh, Rosy

    2014-03-05

    We consider the bifurcation and transition of axially symmetric monopole-antimonopole pair (MAP) and vortex ring solutions in the presence of electric charge for the SU(2) Yang-Mills-Higgs field theory. Here we investigate the properties of MAP/vortex ring solutions with n = 3,? = 0.65, for different Higgs field strength ?. For ? < 4.93, there is only one fundamental branch of vortex ring solution, but at the critical value of ?{sub b} = 4.93, branching happens and 2 sets of new solutions appeared. The new branch with less energy is a full MAP solution while the branch with higher energy contains MAP at the beginning and separation between poles of MAP on the z-axis reduces gradually and at another critical value of ?{sub t} = 14.852, they merge together at z = 0. Beyond this point the solutions change to the vortex ring solutions and a transitions between MAP and vortex ring solutions happens at this branch.

  8. Effects of Combustion-Induced Vortex Breakdown on Flashback Limits of Syngas-Fueled Gas Turbine Combustors

    SciTech Connect (OSTI)

    Ahsan Choudhuri

    2011-03-31

    Turbine combustors of advanced power systems have goals to achieve very low pollutants emissions, fuel variability, and fuel flexibility. Future generation gas turbine combustors should tolerate fuel compositions ranging from natural gas to a broad range of syngas without sacrificing operational advantages and low emission characteristics. Additionally, current designs of advanced turbine combustors use various degrees of swirl and lean premixing for stabilizing flames and controlling high temperature NOx formation zones. However, issues of fuel variability and NOx control through premixing also bring a number of concerns, especially combustor flashback and flame blowout. Flashback is a combustion condition at which the flame propagates upstream against the gas stream into the burner tube. Flashback is a critical issue for premixed combustor designs, because it not only causes serious hardware damages but also increases pollutant emissions. In swirl stabilized lean premixed turbine combustors onset of flashback may occur due to (i) boundary layer flame propagation (critical velocity gradient), (ii) turbulent flame propagation in core flow, (iii) combustion instabilities, and (iv) upstream flame propagation induced by combustion induced vortex breakdown (CIVB). Flashback due to first two foregoing mechanisms is a topic of classical interest and has been studied extensively. Generally, analytical theories and experimental determinations of laminar and turbulent burning velocities model these mechanisms with sufficient precision for design usages. However, the swirling flow complicates the flashback processes in premixed combustions and the first two mechanisms inadequately describe the flashback propensity of most practical combustor designs. The presence of hydrogen in syngas significantly increases the potential for flashback. Due to high laminar burning velocity and low lean flammability limit, hydrogen tends to shift the combustor operating conditions towards flashback regime. Even a small amount of hydrogen in a fuel blend triggers the onset of flashback by altering the kinetics and thermophysical characteristics of the mixture. Additionally, the presence of hydrogen in the fuel mixture modifies the response of the flame to the global effects of stretch and preferential diffusion. Despite its immense importance in fuel flexible combustor design, little is known about the magnitude of fuel effects on CIVB induced flashback mechanism. Hence, this project investigates the effects of syngas compositions on flashback resulting from combustion induced vortex breakdown. The project uses controlled experiments and parametric modeling to understand the velocity field and flame interaction leading to CIVB driven flashback.

  9. Bow-wave-like hydraulic jump and horseshoe vortex around an obstacle in a supercritical open channel flow

    E-Print Network [OSTI]

    Boyer, Edmond

    Bow-wave-like hydraulic jump and horseshoe vortex around an obstacle in a supercritical open the obstacle, two main flow structures are observed: i a hydraulic jump in the near-surface region and ii turbulent regime , the detachment length of the hydraulic jump exceeds the one of the horseshoe vortex

  10. A vortex level set method for the two-way coupling of an incompressible fluid with colliding rigid bodies

    E-Print Network [OSTI]

    Cottet, Georges-Henri

    in a non laminar flow. Here we consider a different approach. The fluid­ solid system is considered rights reserved. Keywords: Incompressible flow; Fluid­solid interaction; Vortex method; Level set methodA vortex level set method for the two-way coupling of an incompressible fluid with colliding rigid

  11. Effect of tube spacing on the vortex shedding characteristics of laminar flow past an inline tube array: A numerical study

    E-Print Network [OSTI]

    Luo, Xiaoyu

    Effect of tube spacing on the vortex shedding characteristics of laminar flow past an inline tube the tubes. Complex flow dynamic phenomena such as reattachment of shear layers, in- duced separation, vortex Accepted 27 October 2008 Available online 14 November 2008 a b s t r a c t The effect of tube spacing

  12. Electron trapping by a current vortex F. Bentosela, a;b P. Exner, c;d and V.A. Zagrebnov a;b

    E-Print Network [OSTI]

    simpler example involves a Pauli electron interacting with a flux tube modelling a vortex magnetic fieldElectron trapping by a current vortex F. Bentosela, a;b P. Exner, c;d and V.A. Zagrebnov a;b a with the magnetic field due to an electric current forming a localized rotationally symmetric vortex. We show

  13. arXiv:cond-mat/0606001v222Jul2006 Electronic states near a quantum fluctuating point vortex in a d-wave superconductor

    E-Print Network [OSTI]

    -wave superconductor. The vortex is treated as a point flux tube, carrying flux of an auxiliary U(1) gauge fieldarXiv:cond-mat/0606001v222Jul2006 Electronic states near a quantum fluctuating point vortex in a d energy electronic states in the vicinity of a vortex under- going quantum zero-point motion in a d

  14. Magnetic monopole versus vortex as gauge-invariant topological objects for quark confinement

    E-Print Network [OSTI]

    Kondo, Kei-Ichi; Shinohara, Toru; Shibata, Akihiro; Kato, Seikou

    2015-01-01

    First, we give a gauge-independent definition of chromomagnetic monopoles in $SU(N)$ Yang-Mills theory which is derived through a non-Abelian Stokes theorem for the Wilson loop operator. Then we discuss how such magnetic monopoles can give a nontrivial contribution to the Wilson loop operator for understanding the area law of the Wilson loop average. Next, we discuss how the magnetic monopole condensation picture are compatible with the vortex condensation picture as another promising scenario for quark confinement. We analyze the profile function of the magnetic flux tube as the non-Abelian vortex solution of $U(N)$ gauge-Higgs model, which is to be compared with numerical simulations of the $SU(N)$ Yang-Mills theory on a lattice. This analysis gives an estimate of the string tension based on the vortex condensation picture, and possible interactions between two non-Abelian vortices.

  15. Spectro-Polarimetric Properties of Small-Scale Plasma Eruptions Driven by Magnetic Vortex Tubes

    E-Print Network [OSTI]

    Kitiashvili, Irina N

    2014-01-01

    Highly turbulent nature of convection on the Sun causes strong multi-scale interaction of subsurface layers with the photosphere and chromosphere. According to realistic 3D radiative MHD numerical simulations ubiquitous small-scale vortex tubes are generated by turbulent flows below the visible surface and concentrated in the intergranular lanes. The vortex tubes can capture and amplify magnetic field, penetrate into chromospheric layers and initiate quasi-periodic flow eruptions that generates Alfv\\'enic waves, transport mass and energy into the solar atmosphere. The simulations revealed high-speed flow patterns, and complicated thermodynamic and magnetic structures in the erupting vortex tubes. The spontaneous eruptions are initiated and driven by strong pressure gradients in the near-surface layers, and accelerated by the Lorentz force in the low chromosphere. In this paper, the simulation data are used to further investigate the dynamics of the eruptions, their spectro-polarimetric characteristics for the...

  16. Magnetic monopole versus vortex as gauge-invariant topological objects for quark confinement

    E-Print Network [OSTI]

    Kei-Ichi Kondo; Takaaki Sasago; Toru Shinohara; Akihiro Shibata; Seikou Kato

    2015-08-08

    First, we give a gauge-independent definition of chromomagnetic monopoles in $SU(N)$ Yang-Mills theory which is derived through a non-Abelian Stokes theorem for the Wilson loop operator. Then we discuss how such magnetic monopoles can give a nontrivial contribution to the Wilson loop operator for understanding the area law of the Wilson loop average. Next, we discuss how the magnetic monopole condensation picture are compatible with the vortex condensation picture as another promising scenario for quark confinement. We analyze the profile function of the magnetic flux tube as the non-Abelian vortex solution of $U(N)$ gauge-Higgs model, which is to be compared with numerical simulations of the $SU(N)$ Yang-Mills theory on a lattice. This analysis gives an estimate of the string tension based on the vortex condensation picture, and possible interactions between two non-Abelian vortices.

  17. Vortex combustor for low NOx emissions when burning lean premixed high hydrogen content fuel

    DOE Patents [OSTI]

    Steele, Robert C. (Woodinville, WA); Edmonds, Ryan G. (Renton, WA); Williams, Joseph T. (Kirkland, WA); Baldwin, Stephen P. (Winchester, MA)

    2009-10-20

    A trapped vortex combustor. The trapped vortex combustor is configured for receiving a lean premixed gaseous fuel and oxidant stream, where the fuel includes hydrogen gas. The trapped vortex combustor is configured to receive the lean premixed fuel and oxidant stream at a velocity which significantly exceeds combustion flame speed in a selected lean premixed fuel and oxidant mixture. The combustor is configured to operate at relatively high bulk fluid velocities while maintaining stable combustion, and low NOx emissions. The combustor is useful in gas turbines in a process of burning synfuels, as it offers the opportunity to avoid use of diluent gas to reduce combustion temperatures. The combustor also offers the possibility of avoiding the use of selected catalytic reaction units for removal of oxides of nitrogen from combustion gases exiting a gas turbine.

  18. Shear Banding and Spatiotemporal Oscillations in Vortex Matter in Nanostructured Superconductors

    E-Print Network [OSTI]

    C. Reichhardt; C. J. Olson Reichhardt

    2009-12-16

    We propose a simple nanostructured pinning array geometry where a rich variety of complex vortex shear banding phenomena can be realized. A single row of pinning sites is removed from a square pinning array. Shear banding effects arise when vortex motion in the pin-free channel nucleates motion of vortices in the surrounding pinned regions, creating discrete steps in the vortex velocity profile away from the channel. Near the global depinning transition, the width of the band of moving vortices undergoes oscillations or fluctuations that can span the entire system. We use simulations to show that these effects should be observable in the transport properties of the system. Similar large oscillations and shear banding effects are known to occur for sheared complex fluids in which different dynamical phases coexist.

  19. Reduction of vortex induced forces and motion through surface roughness control

    DOE Patents [OSTI]

    Bernitsas, Michael M; Raghavan, Kamaldev

    2014-04-01

    Roughness is added to the surface of a bluff body in a relative motion with respect to a fluid. The amount, size, and distribution of roughness on the body surface is controlled passively or actively to modify the flow around the body and subsequently the Vortex Induced Forces and Motion (VIFM). The added roughness, when designed and implemented appropriately, affects in a predetermined way the boundary layer, the separation of the boundary layer, the level of turbulence, the wake, the drag and lift forces, and consequently the Vortex Induced Motion (VIM), and the fluid-structure interaction. The goal of surface roughness control is to decrease/suppress Vortex Induced Forces and Motion. Suppression is required when fluid-structure interaction becomes destructive as in VIM of flexible cylinders or rigid cylinders on elastic support, such as underwater pipelines, marine risers, tubes in heat exchangers, nuclear fuel rods, cooling towers, SPAR offshore platforms.

  20. Random Vortex-Street Model for a Self-Similar Plane Turbulent Jet

    E-Print Network [OSTI]

    Victor L'vov; Anna Pomyalov; Itamar Procaccia; Rama Govindarajan

    2008-03-18

    We ask what determines the (small) angle of turbulent jets. To answer this question we first construct a deterministic vortex-street model representing the large scale structure in a self-similar plane turbulent jet. Without adjustable parameters the model reproduces the mean velocity profiles and the transverse positions of the large scale structures, including their mean sweeping velocities, in a quantitative agreement with experiments. Nevertheless the exact self similar arrangement of the vortices (or any other deterministic model) necessarily leads to a collapse of the jet angle. The observed (small) angle results from a competition between vortex sweeping tending to strongly collapse the jet and randomness in the vortex structure, with the latter resulting in a weak spreading of the jet.

  1. Vortex combustor for low NOX emissions when burning lean premixed high hydrogen content fuel

    DOE Patents [OSTI]

    Steele, Robert C; Edmonds, Ryan G; Williams, Joseph T; Baldwin, Stephen P

    2012-11-20

    A trapped vortex combustor. The trapped vortex combustor is configured for receiving a lean premixed gaseous fuel and oxidant stream, where the fuel includes hydrogen gas. The trapped vortex combustor is configured to receive the lean premixed fuel and oxidant stream at a velocity which significantly exceeds combustion flame speed in a selected lean premixed fuel and oxidant mixture. The combustor is configured to operate at relatively high bulk fluid velocities while maintaining stable combustion, and low NOx emissions. The combustor is useful in gas turbines in a process of burning synfuels, as it offers the opportunity to avoid use of diluent gas to reduce combustion temperatures. The combustor also offers the possibility of avoiding the use of selected catalytic reaction units for removal of oxides of nitrogen from combustion gases exiting a gas turbine.

  2. Tidal deformations of a spinning compact object

    E-Print Network [OSTI]

    Pani, Paolo; Maselli, Andrea; Ferrari, Valeria

    2015-01-01

    The deformability of a compact object induced by a perturbing tidal field is encoded in the tidal Love numbers, which depend sensibly on the object's internal structure. These numbers are known only for static, spherically-symmetric objects. As a first step to compute the tidal Love numbers of a spinning compact star, here we extend powerful perturbative techniques to compute the exterior geometry of a spinning object distorted by an axisymmetric tidal field to second order in the angular momentum. The spin of the object introduces couplings between electric and magnetic deformations and new classes of induced Love numbers emerge. For example, a spinning object immersed in a quadrupolar, electric tidal field can acquire some induced mass, spin, quadrupole, octupole and hexadecapole moments to second order in the spin. The deformations are encoded in a set of inhomogeneous differential equations which, remarkably, can be solved analytically in vacuum. We discuss certain subtleties in defining the multipole mom...

  3. Decoherence of spin-deformed bosonic model

    SciTech Connect (OSTI)

    Dehdashti, Sh.; Mahdifar, A.; Bagheri Harouni, M.; Roknizadeh, R.

    2013-07-15

    The decoherence rate and some parameters affecting it are investigated for the generalized spin-boson model. We consider the spin-bosonic model when the bosonic environment is modeled by the deformed harmonic oscillators. We show that the state of the environment approaches a non-linear coherent state. Then, we obtain the decoherence rate of a two-level system which is in contact with a deformed bosonic environment which is either in thermal equilibrium or in the ground state. By using some recent realization of f-deformed oscillators, we show that some physical parameters strongly affect the decoherence rate of a two-level system. -- Highlights: •Decoherence of the generalized spin-boson model is considered. •In this model the environment consists of f-oscillators. •Via the interaction, the state of the environment approaches non-linear coherent states. •Effective parameters on decoherence are considered.

  4. 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.

    2010-07-28

    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.

  5. Single-vortex pinning and penetration depth in superconducting NdFeAsO1-xFx

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

    Zhang, Jessie T.; Kim, Jeehoon; Huefner, Magdalena; Ye, Cun; Kim, Stella; Canfield, Paul C.; Prozorov, Ruslan; Auslaender, Ophir M.; Hoffman, Jennifer E.

    2015-10-12

    We use a magnetic force microscope (MFM) to investigate single vortex pinning and penetration depth in NdFeAsO1-xFx, one of the highest-Tc iron-based superconductors. In fields up to 20 Gauss, we observe a disordered vortex arrangement, implying that the pinning forces are stronger than the vortex-vortex interactions. We measure the typical force to depin a single vortex, Fdepin ? 4.5 pN, corresponding to a critical current up to Jc ? 7×105 A/cm2. As a result, our MFM measurements allow the first local and absolute determination of the superconducting in-plane penetration depth in NdFeAsO1-xFx, ?ab = 320 ± 60 nm, which ismore »larger than previous bulk measurements.« less

  6. Plastic Deformation of 2D Crumpled Wires

    E-Print Network [OSTI]

    M A F Gomes; V P Brito; A S O Coelho; C C Donato

    2008-11-17

    When a single long piece of elastic wire is injected trough channels into a confining two-dimensional cavity, a complex structure of hierarchical loops is formed. In the limit of maximum packing density, these structures are described by several scaling laws. In this paper it is investigated this packing process but using plastic wires which give origin to completely irreversible structures of different morphology. In particular, it is studied experimentally the plastic deformation from circular to oblate configurations of crumpled wires, obtained by the application of an axial strain. Among other things, it is shown that in spite of plasticity, irreversibility, and very large deformations, scaling is still observed.

  7. Relativistic Electron Vortex Beams: Angular Momentum and Spin-Orbit Interaction

    E-Print Network [OSTI]

    Konstantin Y. Bliokh; Mark R. Dennis; Franco Nori

    2011-09-11

    Motivated by the recent discovery of electron vortex beams carrying orbital angular momentum (AM), we construct exact Bessel-beam solutions of the Dirac equation. They describe relativistic and nonparaxial corrections to the scalar electron beams. We describe the spin and orbital AM of the electron with Berry-phase corrections and predict the intrinsic spin-orbit coupling in free space. This can be observed as a spin-dependent probability distribution of the focused electron vortex beams. Moreover, the magnetic moment is calculated, which shows different $g$-factors for spin and orbital AM and also contains the Berry-phase correction.

  8. Vice President of Core Facilities

    E-Print Network [OSTI]

    MacAdam, Keith

    ) Research Integrity Federal Relations Sponsored Projects Administration, AVPR Advanced Science & Technology Veterinarian Research Communications Centers & Institutes · Center for Applied Energy Research (CAER) · CenterVice President of Research Core Facilities · Clinical Research Development and Operations Center

  9. EFFECT OF GRAIN SIZE ON THE ACOUSTIC EMISSION GENERATED DURING PLASTIC DEFORMATION OF ALUMINUM

    E-Print Network [OSTI]

    Baram, J.

    2013-01-01

    EMISSION GENERATED DURING PLASTIC DEFORMATION OF ALUMINUMEMISSION GENERATED DURING PLASTIC DEFORMATION OF ALUMINUM J.Al 1100 samples during plastic deformation were analyzed

  10. PLASTIC DEFORMATION OF CRYSTALS: ANALYTICAL AND COMPUTER SIMULATION STUDIES OF DISLOCATION GLIDE

    E-Print Network [OSTI]

    Altintas, Sabri

    2011-01-01

    in Rate Processes in Plastic Deformation of Materials, J. C.PLASTIC DEFORMATION OF CRYSTALS: ANALYTICAL AND COMPUTERCAPTIONS FIGURES - iii - PLASTIC DEFORMATION OF CRYSTALS:

  11. Banding in single crystals during plastic deformation

    E-Print Network [OSTI]

    Mahesh, Sivasambu

    Banding in single crystals during plastic deformation M. Arul Kumar a Sivasambu Mahesh a,b a. India. Abstract A rigid-plastic rate-independent crystal plasticity model capable of capturing band- ing such as dense dislocation walls. Key words: crystal plasticity, single crystal, macroscopic shear band, regular

  12. Tidal deformations of a spinning compact object

    E-Print Network [OSTI]

    Paolo Pani; Leonardo Gualtieri; Andrea Maselli; Valeria Ferrari

    2015-06-30

    The deformability of a compact object induced by a perturbing tidal field is encoded in the tidal Love numbers, which depend sensibly on the object's internal structure. These numbers are known only for static, spherically-symmetric objects. As a first step to compute the tidal Love numbers of a spinning compact star, here we extend powerful perturbative techniques to compute the exterior geometry of a spinning object distorted by an axisymmetric tidal field to second order in the angular momentum. The spin of the object introduces couplings between electric and magnetic deformations and new classes of induced Love numbers emerge. For example, a spinning object immersed in a quadrupolar, electric tidal field can acquire some induced mass, spin, quadrupole, octupole and hexadecapole moments to second order in the spin. The deformations are encoded in a set of inhomogeneous differential equations which, remarkably, can be solved analytically in vacuum. We discuss certain subtleties in defining the multipole moments of the central object, which are due to the difficulty in separating the tidal field from the linear response of the object in the solution. By extending the standard procedure to identify the linear response in the static case, we prove analytically that the Love numbers of a Kerr black hole remain zero to second order in the spin. As a by-product, we provide the explicit form for a slowly-rotating, tidally-deformed Kerr black hole to quadratic order in the spin, and discuss its geodesic and geometrical properties.

  13. Joining of advanced materials by superplastic deformation

    DOE Patents [OSTI]

    Goretta, Kenneth C. (Downers Grove, IL); Routbort, Jules L. (Hinsdale, IL); Gutierrez-Mora, Felipe (Woodridge, IL)

    2008-08-19

    A method for utilizing superplastic deformation with or without a novel joint compound that leads to the joining of advanced ceramic materials, intermetallics, and cermets. A joint formed by this approach is as strong as or stronger than the materials joined. The method does not require elaborate surface preparation or application techniques.

  14. Deformation and Forming of Joined Materials

    SciTech Connect (OSTI)

    Carsley, John; Hovanski, Yuri; Clarke, Kester D.; Krajewski, Paul E.

    2014-09-23

    Introductory article to a set of invited papers from the TMS committee on shaping and forming. This paper introduces a set of papers that were prepared to discussing the deformation and forming of joined materials, and to announce an upcoming symposium at the 2015 MS&T meeting in Columbus Ohio.

  15. Partial Dynamical Symmetry in Deformed Nuclei

    E-Print Network [OSTI]

    A. Leviatan

    1996-06-23

    We discuss the notion of partial dynamical symmetry in relation to nuclear spectroscopy. Explicit forms of Hamiltonians with partial $SU(3)$ symmetry are presented in the framework of the interacting boson model of nuclei. An analysis of the resulting spectrum and electromagnetic transitions demonstrates the relevance of such partial symmetry to the spectroscopy of axially deformed nuclei.

  16. Joining of advanced materials by superplastic deformation

    DOE Patents [OSTI]

    Goretta, Kenneth C.; Routbort, Jules L.; Gutierrez-Mora, Felipe

    2005-12-13

    A method for utilizing superplastic deformation with or without a novel joint compound that leads to the joining of advanced ceramic materials, intermetallics, and cermets. A joint formed by this approach is as strong as or stronger than the materials joined. The method does not require elaborate surface preparation or application techniques.

  17. Holistic design for multi-core architectures

    E-Print Network [OSTI]

    Kumar, Rakesh

    2006-01-01

    Design for Adaptability: Power Advantages of A. Discussion of Core Switching . . . . . . . . . . . .power dissipation and expected performance. This simpli?es the design of core- switching

  18. Deformability of Plasmodium falciparum parasitized red blood cells

    E-Print Network [OSTI]

    Mills, John Philip, Ph. D. Massachusetts Institute of Technology

    2007-01-01

    The biophysical properties of the human red blood cell (RBC) permit large deformations required for passage through narrow capillaries and spleen sinusoids. Several pathologic conditions alter RBC deformability that can ...

  19. Low-energy collective modes of deformed superfluid nuclei within...

    Office of Scientific and Technical Information (OSTI)

    Low-energy collective modes of deformed superfluid nuclei within the finite-amplitude method Citation Details In-Document Search Title: Low-energy collective modes of deformed...

  20. Steady state deformation of the Coso Range, east central California...

    Open Energy Info (EERE)

    an area approximately 10 km by 15 km. The deformation is most likely the result of subsidence in an area around the Coso geothermal field. The deformation signal has a...

  1. Large deformation and electrochemistry of polyelectrolyte gels , Xuanhe Zhao b

    E-Print Network [OSTI]

    Suo, Zhigang

    Large deformation and electrochemistry of polyelectrolyte gels Wei Hong a , Xuanhe Zhao b , Zhigang. This paper develops a field theory to couple large deformation and electrochemistry. A specific material

  2. Severe plastic deformation of difficult-to-work alloys 

    E-Print Network [OSTI]

    Yapici, Guney Guven

    2004-09-30

    The present work aims to reveal the microstructural evolution and post-processing mechanical behavior of difficult-to-work alloys upon severe plastic deformation. Severe plastic deformation is applied using equal channel ...

  3. Interaction and Deformation of Viscoelastic Particles. 2. Adhesive Particles

    E-Print Network [OSTI]

    Attard, Phil

    Interaction and Deformation of Viscoelastic Particles. 2. Adhesive Particles Phil Attard Ian Wark, 2001. In Final Form: April 30, 2001 Analyzed is the mutual deformation of adhesive particles the particles' adhesion. An analytic

  4. Effects of subsurface fracture interactions on surface deformation

    E-Print Network [OSTI]

    Jerry, Ruel (Ruel Valentine)

    2013-01-01

    Although the surface deformation resulting from the opening of a single fracture in a layered elastic half-space resembles the observed deformation at the InSalah site, it seems unlikely that only a single fracture is ...

  5. Powder metallurgy processing and deformation characteristics of bulk multimodal nickel

    SciTech Connect (OSTI)

    Farbaniec, L.; Dirras, G.; Krawczynska, A.; Mompiou, F.; Couque, H.; Naimi, F.; Bernard, F.; Tingaud, D.

    2014-08-15

    Spark plasma sintering was used to process bulk nickel samples from a blend of three powder types. The resulting multimodal microstructure was made of coarse (average size ? 135 ?m) spherical microcrystalline entities (the core) surrounded by a fine-grained matrix (average grain size ? 1.5 ?m) or a thick rim (the shell) distinguishable from the matrix. Tensile tests revealed yield strength of ? 470 MPa that was accompanied by limited ductility (? 2.8% plastic strain). Microstructure observation after testing showed debonding at interfaces between the matrix and the coarse entities, but in many instances, shallow dimples within the rim were observed indicating local ductile events in the shell. Dislocation emission and annihilation at grain boundaries and twinning at crack tip were the main deformation mechanisms taking place within the fine-grained matrix as revealed by in-situ transmission electron microscopy. Estimation of the stress from loop's curvature and dislocation pile-up indicates that dislocation emission from grain boundaries and grain boundary overcoming largely contributes to the flow stress. - Highlights: • Bulk multi-modal Ni was processed by SPS from a powder blend. • Ultrafine-grained matrix or rim observed around spherical microcrystalline entities • Yield strength (470 MPa) and ductility (2.8% plastic strain) were measured. • Debonding was found at the matrix/microcrystalline entity interfaces. • In-situ TEM showed twinning, dislocation emission and annihilation at grain boundaries.

  6. Vortex reconnections in atomic condensates at finite temperature A. J. Allen1

    E-Print Network [OSTI]

    Zuccher, Simone

    superfluid turbu- lence, a phenomenon recently also reported in trapped atomic Bose­Einstein condensates, vortex dynamics, quantum turbulence, Bose-Einstein condensates, Superfluid He In classical hydrodynamics 3 He and atomic Bose­Einstein condensates (BECs) is currently debated. For example, one would like

  7. Detection of vortex tubes in solar granulation from observations with Sunrise

    E-Print Network [OSTI]

    Steiner, O; Gonzalez, N Bello; Nutto, Ch; Rezaei, R; Pillet, V Martinez; Navarro, J A Bonet; Iniesta, J C del Toro; Domingo, V; Solanki, S K; Knolker, M; Schmidt, W; Barthol, P; Gandorfer, A

    2010-01-01

    We have investigated a time series of continuum intensity maps and corresponding Dopplergrams of granulation in a very quiet solar region at the disk center, recorded with the Imaging Magnetograph eXperiment (IMaX) on board the balloon-borne solar observatory Sunrise. We find that granules frequently show substructure in the form of lanes composed of a leading bright rim and a trailing dark edge, which move together from the boundary of a granule into the granule itself. We find strikingly similar events in synthesized intensity maps from an ab initio numerical simulation of solar surface convection. From cross sections through the computational domain of the simulation, we conclude that these `granular lanes' are the visible signature of (horizontally oriented) vortex tubes. The characteristic optical appearance of vortex tubes at the solar surface is explained. We propose that the observed vortex tubes may represent only the large-scale end of a hierarchy of vortex tubes existing near the solar surface.

  8. The tangential velocity profile and momentum transfer within a microgravity, vortex separator 

    E-Print Network [OSTI]

    Ellis, Michael Clay

    2009-05-15

    &M University (TAMU) have developed a microgravity vortex separator (MVS) capable of handling both a wide range of inlet conditions and changes in these conditions. To optimize the MVS design, the effects of nozzle area, separator geometry, and inlet flow rate...

  9. RESEARCH ARTICLE Drag and lift reduction of a 3D bluff-body using active vortex

    E-Print Network [OSTI]

    Wesfreid, José Eduardo

    apparatus (chemical industry, energy production). From the academic point of view, it is an exciting-up with motorized vortex generators is proposed. Thanks to this active device. The optimal configurations depending academic and industrial research. From the indus- trial point of view, flow control is a way to increase

  10. Model of coarsening and vortex formation in vibrated granular rods Igor S. Aranson

    E-Print Network [OSTI]

    Tsimring, Lev S.

    Model of coarsening and vortex formation in vibrated granular rods Igor S. Aranson Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439 Lev S. Tsimring Institute for Nonlinear Science spontaneous formation of the long-range orientational order and large- scale vortices in a system of vibrated

  11. 2094 OPTICS LETTERS / Vol. 28, No. 21 / November 1, 2003 Fundamental and vortex solitons in a

    E-Print Network [OSTI]

    Yang, Jianke

    2094 OPTICS LETTERS / Vol. 28, No. 21 / November 1, 2003 Fundamental and vortex solitons in a two-dimensional optical lattice Jianke Yang Department of Mathematics and Statistics, University of Vermont, Burlington-dimensional optically induced waveguide array are reported. In the strong localization regime the fundamental soliton

  12. "Development of a Free Vortex Wake Method Code for Offshore Floating Wind Turbines"

    E-Print Network [OSTI]

    Mountziaris, T. J.

    "Development of a Free Vortex Wake Method Code for Offshore Floating Wind Turbines" Andrew Sciotti Professor Matthew Lackner Shujian Liu Offshore floating wind turbines (OFWTs) require a unique aerodynamic in refining current mathematical models of offshore wind turbines while also allowing efficient simulations

  13. Sediment resuspension and erosion by vortex rings R. J. Munro,1,a

    E-Print Network [OSTI]

    Dalziel, Stuart

    Sediment resuspension and erosion by vortex rings R. J. Munro,1,a N. Bethke,2 and S. B. Dalziel2 1; accepted 26 January 2009; published online 8 April 2009 Particle resuspension and erosion induced-ring propagation speed. The critical conditions for resuspension whereby particles are only just resuspended were

  14. Microoptomechanical pumps assembled and driven by holographic optical vortex Kosta Ladavac

    E-Print Network [OSTI]

    Grier, David

    Microoptomechanical pumps assembled and driven by holographic optical vortex arrays Kosta Ladavac into dynamically reconfigurable microoptomechanical pumps assembled by optical gradient forces and actuated systems has created a need for new meth­ ods to pump and steer fluids through micrometer­scale channels

  15. Microoptomechanical pumps assembled and driven by holographic optical vortex Kosta Ladavac

    E-Print Network [OSTI]

    Grier, David

    Microoptomechanical pumps assembled and driven by holographic optical vortex arrays Kosta Ladavac into dynamically reconfigurable microoptomechanical pumps assembled by optical gradient forces and actuated systems has created a need for new meth- ods to pump and steer fluids through micrometer-scale channels

  16. Hierarchical Colloidal Vortex Rings in a Constant Electric Field Yilong Han and David G. Grier

    E-Print Network [OSTI]

    Grier, David

    in the bulk of charge­stabilized colloidal suspensions when electrohydrodynamic forces due to constant appliedHierarchical Colloidal Vortex Rings in a Constant Electric Field Yilong Han and David G. Grier used [1, 2] to study interfacial col­ loidal electrokinetic phenomena. An aqueous suspension

  17. Hierarchical Colloidal Vortex Rings in a Constant Electric Field Yilong Han and David G. Grier

    E-Print Network [OSTI]

    Grier, David

    in the bulk of charge-stabilized colloidal suspensions when electrohydrodynamic forces due to constant appliedHierarchical Colloidal Vortex Rings in a Constant Electric Field Yilong Han and David G. Grier used [1, 2] to study interfacial col- loidal electrokinetic phenomena. An aqueous suspension

  18. Self-consistent anisotropic oscillator with cranked angular and vortex velocities

    E-Print Network [OSTI]

    G. Rosensteel

    1992-11-05

    The Kelvin circulation is the kinematical Hermitian observable that measures the true character of nuclear rotation. For the anisotropic oscillator, mean field solutions with fixed angular momentum and Kelvin circulation are derived in analytic form. The cranking Lagrange multipliers corresponding to the two constraints are the angular and vortex velocities. Self-consistent solutions are reported with a constraint to constant volume.

  19. Vortex-Pair Dynamics in Anisotropic Bistable Media: A Kinematic Approach Aric Hagberg1

    E-Print Network [OSTI]

    Meron, Ehud

    Alamos, New Mexico 87545, USA 2 Department of Solar Energy and Environmental Physics, BIDR, Ben Gurion type upon rotation by =2. We study vortex-pair dynamics by deriving kinematic equations for a front with contour lines that form a closed loop. Equations of this kind, but for isotropic systems and infinite

  20. A Lagrangian approach to identifying vortex pinch-off Clara O'Farrell1

    E-Print Network [OSTI]

    Dabiri, John O.

    A Lagrangian approach to identifying vortex pinch-off Clara O'Farrell1 and John O. Dabiri2 1 Control and Dynamical Systems, California Institute of Technology, Pasadena, California 91125, USA 2 Graduate Aeronautical Laboratories and Bioengineering, California Institute of Technology, Pasadena

  1. Vortex dynamics in three-dimensional continuous myocardium with fiber rotation: Filament instability and fibrillationa...

    E-Print Network [OSTI]

    Mascia, Corrado

    Vortex dynamics in three-dimensional continuous myocardium with fiber rotation: Filament, or filament. This twist can then significantly alter the dynamics of the filament. This paper explores transmural filament and cause a transition to a wave turbulent state characterized by a high density

  2. Under consideration for publication in J. Fluid Mech. 1 Drop impact into a deep pool: vortex

    E-Print Network [OSTI]

    Deegan, Robert

    Under consideration for publication in J. Fluid Mech. 1 Drop impact into a deep pool: vortex of Michigan, Ann Arbor, Michigan 48109, USA 2 Division of Physical Sciences and Engineering & Clean Combustion Arabia 3 Physics of Fluids Group, Faculty of Science and Technology, Mesa+ Institute, University

  3. Instabilities due a vortex at a density interface: gravitational and centrifugal effects

    E-Print Network [OSTI]

    Dixit, Harish

    Instabilities due a vortex at a density interface: gravitational and centrifugal effects Harish N showed recently that the flow is subject to centrifugal Rayleigh-Taylor and spiral Kelvin for example [5]). In the absence of gravity, centrifugal forces are predominant, and we showed recently [4

  4. Aging memory and glassiness of a driven vortex , Guohong Li1

    E-Print Network [OSTI]

    Andrei, Eva Y.

    1 Aging memory and glassiness of a driven vortex system. Xu Du1 , Guohong Li1 , Eva Y. Andrei1 , M memory, aging and nonlinear-dynamics. Glasses[1-11], interfaces[12] and fractures are some examples[13 the deviation from equilibrium. After removing the force, the system ages with time and its subsequent response

  5. Spin waves in circular soft magnetic dots at the crossover between vortex and single domain state

    E-Print Network [OSTI]

    Metlushko, Vitali

    Facility, Cornell University, Ithaca, New York, 14853 USA 6Departamento de Fisica de Materiales We report on linear spin dynamics in the vortex state of Permalloy cylindrical dots subjected In many physical systems such as liquids, plasma, super- conductors, ferromagnets, etc., the topological

  6. Rotational stability of tidally deformed planetary I. Matsuyama1

    E-Print Network [OSTI]

    Nimmo, Francis

    Rotational stability of tidally deformed planetary bodies I. Matsuyama1 and F. Nimmo2 Received 11 consider the true polar wander (rotational variations driven by mass redistribution) of tidally deformed planetary bodies. The rotation pole of bodies without tidal deformation is stabilized by the component

  7. Poludnista Dorsa, Venus: History and context of a deformation belt

    E-Print Network [OSTI]

    Hansen, Vicki

    Poludnista Dorsa, Venus: History and context of a deformation belt D. A. Young and V. L. Hansen is combined with altimetry data test models of deformation belt evolution in Venus's lowlands. Poludnista Dorsa, a complex 2000-km-long deformation belt, is highly segmented and broadly time transgressive. Long

  8. XT Node Architecture Let's Review: Dual Core v. Quad Core

    E-Print Network [OSTI]

    DDR2 · 10GB/s peak @ 667MHz · 8GB/s nominal STREAMs Quad Core · Core · 2.1Ghz clock frequency · SSE to L1,L2,L3 · Memory · Dual Channel DDR2 · 12GB/s peak @ 800MHz · 10GB/s nominal STREAMs #12;Cray XT4 Node 9.6 GB/sec 9.6GB/sec 9.6 GB/sec 9.6GB/sec 2 ­ 8 GB 12.8 GB/sec direct connect memory (DDR 800) 6

  9. 80 units of core courses 70 units of core courses 70 units of core courses 80 units of core courses Semester 1 Semester 1 Semester 1 Semester 1

    E-Print Network [OSTI]

    Fleming, Andrew J.

    80 units of core courses 70 units of core courses 70 units of core courses 80 units of core courses Semester 1 Semester 1 Semester 1 Semester 1 ARBE1303 10 units ARBE2101 10 units ARBE3100 10 units ARBE4101 10 units Introduction to the Construction Industry Construction Ecology 2 Construction Technology 3

  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)

    2015-01-01

    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, F.E.

    1992-12-08

    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.

  12. Reactor core isolation cooling system

    DOE Patents [OSTI]

    Cooke, Franklin E. (San Jose, CA)

    1992-01-01

    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.

  13. 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

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

    E-Print Network [OSTI]

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

    2006-01-01

    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...

  15. ${\\cal D}$-deformed harmonic oscillators

    E-Print Network [OSTI]

    F. Bagarello; F. Gargano; D. Volpe

    2014-12-30

    We analyze systematically several deformations arising from two-dimensional harmonic oscillators which can be described in terms of $\\cal{D}$-pseudo bosons. They all give rise to exactly solvable models, described by non self-adjoint hamiltonians whose eigenvalues and eigenvectors can be found adopting the quite general framework of the so-called $\\cal{D}$-pseudo bosons. In particular, we show that several models previously introduced in the literature perfectly fit into this scheme.

  16. Biaxially textured articles formed by plastic deformation

    DOE Patents [OSTI]

    Goyal, Amit (Knoxville, TN)

    2001-01-01

    A method of preparing a biaxially textured article comprises the steps of providing a metal preform, coating or laminating the preform with a metal layer, deforming the layer to a sufficient degree, and rapidly recrystallizing the layer to produce a biaxial texture. A superconducting epitaxial layer may then be deposited on the biaxial texture. In some embodiments the article further comprises buffer layers, electromagnetic devices or electro-optical devices.

  17. A shapeable material without plastic deformation

    E-Print Network [OSTI]

    Naomi Oppenheimer; Thomas A. Witten

    2015-06-01

    Randomly crumpled sheets have shape memory. In order to understand the basis of this form of memory, we simulate triangular lattices of springs whose lengths are altered to create a topography with multiple potential energy minima. We then deform these lattices into different shapes and investigate their ability to retain the imposed shape when the energy is relaxed. The lattices are able to retain a range of curvatures. Under moderate forcing from a state of local equilibrium, the lattices deform by several percent but return to their retained shape when the forces are removed. By increasing the forcing until an irreversible motion occurs, we find that the transitions between remembered shapes show co-operativity among several springs. For fixed lattice structures, the shape memory tends to decrease as the lattice is enlarged; we propose ways to counter this decrease by modifying the lattice geometry. We survey the energy landscape by displacing individual nodes. An extensive fraction of these nodes proves to be bistable; they retain their displaced position when the energy is relaxed. Bending the lattice to a stable curved state alters the pattern of bistable nodes. We discuss this shapeability in the context of other forms of material memory and contrast it with the shapeability of plastic deformation. We outline the prospects for making real materials based on these principles.

  18. Shock wave absorber having a deformable liner

    DOE Patents [OSTI]

    Youngdahl, C.K.; Wiedermann, A.H.; Shin, Y.W.; Kot, C.A.; Ockert, C.E.

    1983-08-26

    This invention discloses a shock wave absorber for a piping system carrying liquid. The absorber has a plastically deformable liner defining the normal flow boundary for an axial segment of the piping system, and a nondeformable housing is spaced outwardly from the liner so as to define a gas-tight space therebetween. The flow capacity of the liner generally corresponds to the flow capacity of the piping system line, but the liner has a noncircular cross section and extends axially of the piping system line a distance between one and twenty times the diameter thereof. Gas pressurizes the gas-tight space equal to the normal liquid pressure in the piping system. The liner has sufficient structural capacity to withstand between one and one-half and two times this normal liquid pressures; but at greater pressures it begins to plastically deform initially with respect to shape to a more circular cross section, and then with respect to material extension by circumferentially stretching the wall of the liner. A high energy shock wave passing through the liner thus plastically deforms the liner radially into the gas space and progressively also as needed in the axial direction of the shock wave to minimize transmission of the shock wave beyond the absorber.

  19. Rietveld Analysis of X-ray Powder Diffraction Patterns as a Potential Tool for the Identification of Impact-deformed Carbonate Rocks

    SciTech Connect (OSTI)

    Huson, Sarah A.; Foit, Franklin F.; Watkinson, A. J.; Pope, Michael C.

    2009-11-01

    Previous X-ray powder diffraction (XRD) studies revealed that shock deformed carbonates and quartz have broader XRD patterns than those of unshocked samples. Entire XRD patterns, single peak profiles and Rietveld refined parameters of carbonate samples from the Sierra Madera impact crater, west Texas, unshocked equivalent samples from 95 miles north of the crater and the Mission Canyon Formation of southwest Montana and western Wyoming were used to evaluate the use of X-ray powder diffraction as a potential tool for distinguishing impact deformed rocks from unshocked and tectonically deformed rocks. At Sierra Madera dolostone and limestone samples were collected from the crater rim (lower shock intensity) and the central uplift (higher shock intensity). Unshocked equivalent dolostone samples were collected from well cores drilled outside of the impact crater. Carbonate rocks of the Mission Canyon Formation were sampled along a transect across the tectonic front of the Sevier and Laramide orogenic belts. Whereas calcite subjected to significant shock intensities at the Sierra Madera impact crater can be differentiated from tectonically deformed calcite from the Mission Canyon Formation using Rietveld refined peak profiles, weakly shocked calcite from the crater rim appears to be indistinguishable from the tectonically deformed calcite. In contrast, Rietveld analysis readily distinguishes shocked Sierra Madera dolomite from unshocked equivalent dolostone samples from outside the crater and tectonically deformed Mission Canyon Formation dolomite.

  20. PUBLISHED ONLINE: 18 JANUARY 2009 DOI: 10.1038/NPHYS1177 Evidence for an oscillating soliton/vortex ring by

    E-Print Network [OSTI]

    Loss, Daniel

    soliton/vortex ring by density engineering of a Bose­Einstein condensate I. Shomroni, E. Lahoud, S. Levy and J. Steinhauer* When two Bose­Einstein condensates collide with high collisional energy

  1. A scatter diagram approach to the selection of design currents for prediction of marine riser vortex-induced vibration

    E-Print Network [OSTI]

    Donnelly, Jessica Mary

    2004-01-01

    This paper describes a scatter diagram approach for the classification of large numbers of current profiles for use in the prediction of riser fatigue damage due to vortex-induced vibration. Scatter diagrams have long been ...

  2. arXiv:1206.2498v2[cond-mat.other]19Nov2012 Quantum vortex reconnections

    E-Print Network [OSTI]

    Caliari, Marco

    (Dated: 21 November 2012) We study reconnections of quantum vortices by numerically solving the governing . They are the key to understanding quantum turbulence8 , a disordered state of vortex lines which is easily created

  3. Contributions of the wall boundary layer to the formation of the counter-rotating vortex pair in transverse jets

    E-Print Network [OSTI]

    Schlegel, Fabrice

    Using high-resolution 3-D vortex simulations, this study seeks a mechanistic understanding of vorticity dynamics in transverse jets at a finite Reynolds number. A full no-slip boundary condition, rigorously formulated in ...

  4. Large core fiber optic cleaver

    DOE Patents [OSTI]

    Halpin, J.M.

    1996-03-26

    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.

  5. Chemflex Overview: Common Chemistry core

    E-Print Network [OSTI]

    Gilchrist, James F.

    Advanced chemistry laboratory I CHM 335 3 Advanced chemistry laboratory II Mat 33 3 Engineering materialsChemflex Overview: Common Chemistry core CHM 40, 41 (or CHM 30, 31) 8 Introductory chemistry CHM 110,111,112,113 8 Organic chemistry CHM 332 3 Analytical chemistry CHM 201*** 2 Technical writing CHM

  6. Large core fiber optic cleaver

    DOE Patents [OSTI]

    Halpin, John M. (Livermore, CA)

    1996-01-01

    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.

  7. Stability of Molten Core Materials

    SciTech Connect (OSTI)

    Layne Pincock; Wendell Hintze

    2013-01-01

    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.

  8. The enigma of post-perovskite anisotropy: deformation versus transformation textures

    SciTech Connect (OSTI)

    Miyagi, Lowell; Kanitpanyacharoen, Waruntorn; Stackhouse, Stephen; Militzer, Burkhard; Wenk, Hans-Rudolf

    2012-01-20

    The D'' region that lies just above the core mantle boundary exhibits complex anisotropy that this is likely due to preferred orientation (texturing) of the constituent minerals. (Mg,Fe)SiO{sub 3} post-perovskite is widely thought to be the major mineral phase of the D''. Texture development has been studied in various post-perovskite phases (MgSiO{sub 3}, MgGeO{sub 3}, and CaIrO{sub 3}), and different results were obtained. To clarify this controversy, we report on transformation and deformation textures in MgGeO{sub 3} post-perovskite synthesized and deformed at room temperature in the diamond anvil cell. Transformed from the enstatite phase, MgGeO{sub 3} post-perovskite exhibits a transformation texture characterized by (100) planes at high angles to the direction of compression. Upon subsequent deformation, this texture changes and (001) lattice planes become oriented nearly perpendicular to compression, consistent with dominant (001)[100] slip. When MgGeO{sub 3} post-perovskite is synthesized from the perovskite phase, a different transformation texture is observed. This texture has (001) planes at high angle to compression and becomes slightly stronger upon compression. We also find that the yield strength of MgGeO{sub 3} post-perovskite is dependent on grain size and texture. Finer-grained samples exhibit higher yield strength and are harder to induce plastic deformation. Strong textures also affect the yield strength and can result in higher differential stresses. The inferred dominant (001) slip for pPv is significant for geophysics, because, when applied to geodynamic convection models, it predicts the observed anisotropies of S-waves as well as an anti-correlation between P- and S-waves.

  9. Logging-while-coring method and apparatus

    DOE Patents [OSTI]

    Goldberg, David S.; Myers, Gregory J.

    2007-01-30

    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.

  10. Logging-while-coring method and apparatus

    DOE Patents [OSTI]

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

    2007-11-13

    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.

  11. General rotating quantum vortex filaments in the low-temperature Svistunov model of the local induction approximation

    SciTech Connect (OSTI)

    Van Gorder, Robert A.

    2014-06-15

    In his study of superfluid turbulence in the low-temperature limit, Svistunov [“Superfluid turbulence in the low-temperature limit,” Phys. Rev. B 52, 3647 (1995)] derived a Hamiltonian equation for the self-induced motion of a vortex filament. Under the local induction approximation (LIA), the Svistunov formulation is equivalent to a nonlinear dispersive partial differential equation. In this paper, we consider a family of rotating vortex filament solutions for the LIA reduction of the Svistunov formulation, which we refer to as the 2D LIA (since it permits a potential formulation in terms of two of the three Cartesian coordinates). This class of solutions holds the well-known Hasimoto-type planar vortex filament [H. Hasimoto, “Motion of a vortex filament and its relation to elastica,” J. Phys. Soc. Jpn. 31, 293 (1971)] as one reduction and helical solutions as another. More generally, we obtain solutions which are periodic in the space variable. A systematic analytical study of the behavior of such solutions is carried out. In the case where vortex filaments have small deviations from the axis of rotation, closed analytical forms of the filament solutions are given. A variety of numerical simulations are provided to demonstrate the wide range of rotating filament behaviors possible. Doing so, we are able to determine a number of vortex filament structures not previously studied. We find that the solution structure progresses from planar to helical, and then to more intricate and complex filament structures, possibly indicating the onset of superfluid turbulence.

  12. CORE SHAPES AND ORIENTATIONS OF CORE-SÉRSIC GALAXIES

    SciTech Connect (OSTI)

    Dullo, Bililign T.; Graham, Alister W., E-mail: Bdullo@astro.swin.edu.au [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, Victoria 3122 (Australia)

    2015-01-01

    The inner and outer shapes and orientations of core-Sérsic galaxies may hold important clues to their formation and evolution. We have therefore measured the central and outer ellipticities and position angles for a sample of 24 core-Sérsic galaxies using archival Hubble Space Telescope (HST) images and data. By selecting galaxies with core-Sérsic break radii R{sub b} —a measure of the size of their partially depleted core—that are ? 0.''2, we find that the ellipticities and position angles are quite robust against HST seeing. For the bulk of the galaxies, there is a good agreement between the ellipticities and position angles at the break radii and the average outer ellipticities and position angles determined over R {sub e}/2 < R < R {sub e}, where R {sub e} is the spheroids' effective half light radius. However there are some interesting differences. We find a median ''inner'' ellipticity at R{sub b} of ?{sub med} = 0.13 ± 0.01, rounder than the median ellipticity of the ''outer'' regions ?{sub med} = 0.20 ± 0.01, which is thought to reflect the influence of the central supermassive black hole at small radii. In addition, for the first time we find a trend, albeit weak (2? significance), such that galaxies with larger (stellar deficit-to-supermassive black hole) mass ratios—thought to be a measure of the number of major dry merger events—tend to have rounder inner and outer isophotes, suggesting a connection between the galaxy shapes and their merger histories. We show that this finding is not simply reflecting the well known result that more luminous galaxies are rounder, but it is no doubt related.

  13. Extended core for motor/generator

    DOE Patents [OSTI]

    Shoykhet, Boris A.

    2006-08-22

    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. Extended core for motor/generator

    DOE Patents [OSTI]

    Shoykhet, Boris A.

    2005-05-10

    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.

  15. Large amplitude spin torque vortex oscillations at zero external field using a perpendicular spin polarizer

    SciTech Connect (OSTI)

    Dussaux, A.; Rache Salles, B.; Jenkins, A. S.; Bortolotti, P.; Grollier, J.; Cros, V.; Fert, A.; Khvalkovskiy, A. V.; Kubota, H.; Fukushima, A.; Yakushiji, K.; Yuasa, S.

    2014-07-14

    We investigate the microwave response of a spin transfer vortex based oscillator in a magnetic tunnel junction with an in-plane reference layer combined with a spin valve with an out-of-plane magnetization spin polarizing layer. The main advantage of this perpendicular spin polarizer is to induce a large spin transfer force even at zero magnetic field, thus leading to a record emitted power (up to 0.6??W) associated to a very narrow spectral linewidth of a few hundreds of kHz. The characteristics of this hybrid vortex based spin transfer nano-oscillator obtained at zero field and room temperature are of great importance for applications based on rf spintronic devices as integrated and tunable microwave source and/or microwave detector.

  16. A new reversal mode in exchange coupled antiferromagnetic/ferromagnetic disks: distorted viscous vortex

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

    Gilbert, Dustin A.; Ye, Li; Varea, Aïda; Agramunt-Puig, Sebastià; del Valle, Nuria; Navau, Carles; López-Barbera, José Francisco; Buchanan, Kristen S.; Hoffmann, Axel; Sánchez, Alvar; et al

    2015-04-28

    Magnetic vortices have generated intense interest in recent years due to their unique reversal mechanisms, fascinating topological properties, and exciting potential applications. In addition, the exchange coupling of magnetic vortices to antiferromagnets has also been shown to lead to a range of novel phenomena and functionalities. Here we report a new magnetization reversal mode of magnetic vortices in exchange coupled Ir20Mn80/Fe20Ni80 microdots: distorted viscous vortex reversal. In contrast to the previously known or proposed reversal modes, the vortex is distorted close to the interface and viscously dragged due to the uncompensated spins of a thin antiferromagnet, which leads to unexpectedmore »asymmetries in the annihilation and nucleation fields. These results provide a deeper understanding of the physics of exchange coupled vortices and may also have important implications for applications involving exchange coupled nanostructures.« less

  17. Observation of the Larmor and Gouy Rotations with Electron Vortex Beams

    E-Print Network [OSTI]

    Giulio Guzzinati; Peter Schattschneider; Konstantin Bliokh; Franco Nori; Jo Verbeeck

    2013-02-25

    Electron vortex beams carrying intrinsic orbital angular momentum (OAM) are produced in electron microscopes where they are controlled and focused using magnetic lenses. We observe various rotational phenomena arising from the interaction between the OAM and magnetic lenses. First, the Zeeman coupling, proportional to the OAM and magnetic field strength, produces an OAM-independent Larmor rotation of a mode superposition inside the lens. Second, hen passing through the focal plane, the electron beam acquires an additional Gouy phase dependent on the absolute value of the OAM. This brings about the Gouy rotation of the superposition image proportional to the sign of the OAM. A combination of the Larmor and Gouy effects can result in the addition (or subtraction) of rotations, depending on the OAM sign. This behaviour is unique to electron vortex beams and has no optical counterpart, as Larmor rotation occurs only for charged particles. Our experimental results are in agreement with recent theoretical predictions.

  18. Vortex Formation and Evolution in Planet Harboring Disks under Thermal Relaxation

    E-Print Network [OSTI]

    Gomes, A Lobo; Uribe, A L; Pinilla, P; Surville, C

    2015-01-01

    We study the evolution of planet-induced vortices in radially stratified disks, with initial conditions allowing for radial buoyancy. For this purpose we run global two dimensional hydrodynamical simulations, using the PLUTO code. Planet-induced vortices are a product of the Rossby wave instability (RWI) triggered in the edges of a planetary gap. In this work we assess the influence of radial buoyancy for the development of the vortices. We found that radial buoyancy leads to smoother planetary gaps, which generates weaker vortices. This effect is less pronounced for locally isothermal and quasi-isothermal (very small cooling rate) disks. We observed the formation of two generations of vortices. The first generation of vortices is formed in the outer wall of the planetary gap. The merged primary vortex induces accretion, depleting the mass on its orbit. This process creates a surface density enhancement beyond the primary vortex position. The second generation of vortices arise in this surface density enhance...

  19. Quasi-classical approximation in vortex filament dynamics. Integrable systems, gradient catastrophe and flutter

    E-Print Network [OSTI]

    B. G. Konopelchenko; G. Ortenzi

    2012-06-13

    Quasiclassical approximation in the intrinsic description of the vortex filament dynamics is discussed. Within this approximation the governing equations are given by elliptic system of quasi-linear PDEs of the first order. Dispersionless Da Rios system and dispersionless Hirota equation are among them. They describe motion of vortex filament with slow varying curvature and torsion without or with axial flow. Gradient catastrophe for governing equations is studied. It is shown that geometrically this catastrophe manifests as a fast oscillation of a filament curve around the rectifying plane which resembles the flutter of airfoils. Analytically it is the elliptic umbilic singularity in the terminology of the catastrophe theory. It is demonstrated that its double scaling regularization is governed by the Painleve' I equation.

  20. Weakening of the Stratospheric Polar Vortex by Arctic Sea-Ice Loss

    SciTech Connect (OSTI)

    Kim, Baek-Min; Son, Seok-Woo; Min, Seung-Ki; Jeong, Jee-Hoon; Kim, Seong-Joong; Zhang, Xiangdong; Shim, Taehyoun; Yoon, Jin-Ho

    2014-09-02

    Successive cold winters of severely low temperatures in recent years have had critical social and economic impacts on the mid-latitude continents in the Northern Hemisphere. Although these cold winters are thought to be partly driven by dramatic losses of Arctic sea ice, the mechanism that links sea ice loss to cold winters remains a subject of debate. Here, by conducting observational analyses and model experiments, we show how Arctic sea ice loss and cold winters in extra-polar regions are dynamically connected through the polar stratosphere. We find that decreased sea ice cover during early winter months (November-December), especially over the Barents-Kara seas, enhance the upward propagation of planetary-scale waves with wavenumbers of 1 and 2, subsequently weakening the stratospheric polar vortex in mid-winter (January- February). The weakened polar vortex preferentially induces a negative phase of Arctic Oscillation at the surface, resulting in low temperatures in mid-latitudes.

  1. Magnetic vortex crystal formation in the antidot complement of square artificial spin ice

    SciTech Connect (OSTI)

    Araujo, C. I. L. de Silva, R. C.; Ribeiro, I. R. B.; Nascimento, F. S.; Felix, J. F.; Ferreira, S. O.; Moura-Melo, W. A.; Pereira, A. R.; Mól, L. A. S.

    2014-03-03

    We have studied ferromagnetic nickel thin films patterned with square lattices of elongated antidots that are negative analogues of square artificial spin ice. Micromagnetic simulations and direct current magnetic moment measurements reveal in-plane anisotropy of the magnetic hysteresis loops, and the formation of a dense array of magnetic vortices with random polarization and chirality. These multiply-connected antidot arrays could be superior to lattices of disconnected nanodisks for investigations of vortex switching by applied electric current.

  2. The Minimal Geometric Deformation Approach Extended

    E-Print Network [OSTI]

    Roberto Casadio; Jorge Ovalle; Roldao da Rocha

    2015-09-07

    The minimal geometric deformation approach was introduced in order to study the exterior space-time around spherically symmetric self-gravitating systems, like stars or similar astrophysical objects as well, in the Randall-Sundrum brane-world framework. A consistent extension of this approach is developed here, which contains modifications of both the time component and the radial component of a spherically symmetric metric. A modified Schwarzschild geometry is obtained as an example of its simplest application, and a new solution potentially useful to describe stars in the brane-world is also presented.

  3. Comment on “General rotating quantum vortex filaments in the low-temperature Svistunov model of the local induction approximation” [Phys. Fluids 26, 065105 (2014)

    SciTech Connect (OSTI)

    Hietala, Niklas Hänninen, Risto

    2014-11-15

    Van Gorder considers a formulation of the local induction approximation, which allows the vortex to move in the direction of the reference axis [“General rotating quantum vortex filaments in the low-temperature Svistunov model of the local induction approximation,” Phys. Fluids 26, 065105 (2014)]. However, in his analytical and numerical study he does not use it. A mistake in the torsion of a helical vortex is also corrected.

  4. Laminated electromagnetic pump stator core

    DOE Patents [OSTI]

    Fanning, A.W.

    1995-08-08

    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.

  5. Coring in deep hardrock formations

    SciTech Connect (OSTI)

    Drumheller, D.S.

    1988-08-01

    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.

  6. Acoustic Emissions Monitoring during Inelastic Deformation of Porous Sandstone: Comparison of Three Modes of Deformation

    E-Print Network [OSTI]

    Fortin, Jérôme

    important processes in the oil and gas industry. Hydrocarbon production decreases the pore pressure increases. Under a relatively low effective confining pressure the differential stress attains a peak before--In some reservoirs, large deformations can occur during oil or gas production because of the effective

  7. Overprinting Deformations in Mantle Rocks, Dun Mountain, New Zealand 

    E-Print Network [OSTI]

    Donnelly, Sara

    2014-04-25

    ; Hansen et al., 2012a). Understanding these relationships as well as the nature of deformation in poly- and mono- mineralic rocks give insight to natural deformations in the mantle. Understanding of mantle deformation comes from coupling studies...-pyroxene formulations and argued that the thermometer developed by Taylor (1998) most accurately reproduced temperatures of laboratory experiments designed to equilibrate co-existing pyroxenes. We have applied 22 Figure 8: REE and trace element...

  8. Granular Dynamics in Pebble Bed Reactor Cores

    E-Print Network [OSTI]

    Laufer, Michael Robert

    2013-01-01

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

  9. Triaxially deformed relativistic point-coupling model for $?$ hypernuclei: a quantitative analysis of hyperon impurity effect on nuclear collective properties

    E-Print Network [OSTI]

    W. X. Xue; J. M. Yao; K. Hagino; Z. P. Li; H. Mei; Y. Tanimura

    2015-02-18

    The impurity effect of hyperon on atomic nuclei has received a renewed interest in nuclear physics since the first experimental observation of appreciable reduction of $E2$ transition strength in low-lying states of hypernucleus $^{7}_\\Lambda$Li. Many more data on low-lying states of $\\Lambda$ hypernuclei will be measured soon for $sd$-shell nuclei, providing good opportunities to study the $\\Lambda$ impurity effect on nuclear low-energy excitations. We carry out a quantitative analysis of $\\Lambda$ hyperon impurity effect on the low-lying states of $sd$-shell nuclei at the beyond-mean-field level based on a relativistic point-coupling energy density functional (EDF), considering that the $\\Lambda$ hyperon is injected into the lowest positive-parity ($\\Lambda_s$) and negative-parity ($\\Lambda_p$) states. We adopt a triaxially deformed relativistic mean-field (RMF) approach for hypernuclei and calculate the $\\Lambda$ binding energies of hypernuclei as well as the potential energy surfaces (PESs) in $(\\beta, \\gamma)$ deformation plane. We also calculate the PESs for the $\\Lambda$ hypernuclei with good quantum numbers using a microscopic particle rotor model (PRM) with the same relativistic EDF. The triaxially deformed RMF approach is further applied in order to determine the parameters of a five-dimensional collective Hamiltonian (5DCH) for the collective excitations of triaxially deformed core nuclei. Taking $^{25,27}_{\\Lambda}$Mg and $^{31}_{\\Lambda}$Si as examples, we analyse the impurity effects of $\\Lambda_s$ and $\\Lambda_p$ on the low-lying states of the core nuclei...

  10. Flow rate--pressure drop relation for deformable shallow microfluidic...

    Office of Scientific and Technical Information (OSTI)

    Conference: Flow rate--pressure drop relation for deformable shallow microfluidic channels Citation Details In-Document Search Title: Flow rate--pressure drop relation for...

  11. Modeling Of Surface Deformation From Satellite Radar Interferometry...

    Open Energy Info (EERE)

    with ground-based leveling observations. Two main subsidence areas are observed in the geothermal field, with maximum vertical and horizontal deformation rates of up to 30 mm...

  12. Author's personal copy Large deformation and electrochemistry of polyelectrolyte gels

    E-Print Network [OSTI]

    Hong, Wei

    Author's personal copy Large deformation and electrochemistry of polyelectrolyte gels Wei Hong and electrochemistry. A specific material model is described, including the effects of stretching the network, mixing

  13. Resonant states of deformed nuclei in complex scaling method

    E-Print Network [OSTI]

    Quan Liu; Jian-You Guo; Zhong-Ming Niu; Shou-Wan Chen

    2012-11-29

    We develop a complex scaling method for describing the resonances of deformed nuclei and present a theoretical formalism for the bound and resonant states on the same footing. With $^{31}$Ne as an illustrated example, we have demonstrated the utility and applicability of the extended method and have calculated the energies and widths of low-lying neutron resonances in $^{31}$Ne. The bound and resonant levels in the deformed potential are in full agreement with those from the multichannel scattering approach. The width of the two lowest-lying resonant states shows a novel evolution with deformation and supports an explanation of the deformed halo for $^{31}$Ne.

  14. The effect of nuclear deformation on level statistics

    E-Print Network [OSTI]

    A. Al-Sayed

    2009-03-01

    We analyze the nearest neighbor spacing distributions of low-lying 2+ levels of even-even nuclei. We grouped the nuclei into classes defined by the quadrupole deformation parameter (Beta2). We calculate the nearest neighbor spacing distributions for each class. Then, we determine the chaoticity parameter for each class with the help of the Bayesian inference method. We compare these distributions to a formula that describes the transition to chaos by varying a tuning parameter. This parameter appears to depend in a non-trivial way on the nuclear deformation, and takes small values indicating regularity in strongly deformed nuclei and especially in those having an oblate deformation.

  15. STATISTICAL MECHANICS MODELING OF MESOSCALE DEFORMATION IN METALS...

    Office of Scientific and Technical Information (OSTI)

    and computational modeling of dislocation dynamics of mesoscale deformation of metal single crystals. Specifically, the work aimed to implement a continuum statistical...

  16. Cell Motility and Deformability in the Pathogenesis of Lung Cancer

    E-Print Network [OSTI]

    Pagano, Paul Carmelo

    2015-01-01

    tumor-initiating cells (TICs), cells capable of repopulatingby deformability and analyzed for TIC properties, includingdeformability relates to the TIC phenotype and how they

  17. Sandia Energy - Elucidating the Role of Twin Boundaries in Deformation...

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

    Impact Coupled experiment and modeling reveal the dramatic and complex impact of high-density twin boundaries on microstructure evolution and deformation mechanisms Research...

  18. Ruthenium Aluminides: Deformation Mechanisms and Substructure Development

    SciTech Connect (OSTI)

    Tresa M. Pollock

    2005-05-11

    Structural and functional materials that can operate in severe, high temperature environments are key to the operation of a wide range of energy generation systems. Because continued improvements in the energy efficiency of these systems is critical, the need for new materials with higher temperature capabilities is inevitable. Intermetallic compounds, with strong bonding and generally high melting points offer this possibility for a broad array of components such as coatings, electrode materials, actuators and/or structural elements. RuAl is a very unusual intermetallic compound among the large number of B2compounds that have been identified and investigated to date. This material has a very high melting temperature of 2050?C, low thermal expansion, high thermal conductivity and good corrosion resistance. Unlike most other high temperature B2 intermetallics, RuAl possesses good intrinsic deformability at low temperatures. In this program fundamental aspects of low and high temperature mechanical properties and deformation mechanisms in binary and higher order RuAl-based systems have been investigated. Alloying additions of interest included platinum, boron and niobium. Additionally, preliminary studies on high temperature oxidation behavior of these materials have been conducted.

  19. Spin paramagnetic deformation of a neutron star

    E-Print Network [OSTI]

    Suvorov, A G; Melatos, A

    2015-01-01

    Quantum mechanical corrections to the hydromagnetic force balance equation, derived from the microscopic Schr\\"{o}dinger-Pauli theory of quantum plasmas, modify the equilibrium structure and hence the mass quadrupole moment of a neutron star. It is shown here that the dominant effect --- spin paramagnetism --- is most significant in a magnetar, where one typically has $\\mu_{B}|\\boldsymbol{B}|\\gtrsim k_B T_e$, where $\\mu_{B}$ is the Bohr magneton, $\\boldsymbol{B}$ is the magnetic field, and $T_e$ is the electron temperature. The spin paramagnetic deformation of a nonbarotropic magnetar with a linked poloidal-toroidal magnetic field is calculated to be up to ${{\\sim 10}}$ times greater than the deformation caused solely by the Lorentz force. It depends on the degree of Pauli blocking by conduction electrons and the propensity to form magnetic domains, processes which are incompletely modelled at magnetar field strengths. The star becomes more oblate, as the toroidal field component strengthens. The result impli...

  20. Primordial fluctuations from deformed quantum algebras

    SciTech Connect (OSTI)

    Day, Andrew C. [Department of Applied Mathematics, University of Western Ontario London, ON, Canada N6A 5B7 (Canada); Brown, Iain A. [Institute of Theoretical Astrophysics, University of Oslo P.O. Box 1029 Blindern, N-0315 Oslo (Norway); Seahra, Sanjeev S., E-mail: aday46@uwo.ca, E-mail: ibrown@astro.uio.no, E-mail: sseahra@unb.ca [Department of Mathematics and Statistics, University of New Brunswick Fredericton, NB, Canada E3B 5A3 (Canada)

    2014-03-01

    We study the implications of deformed quantum algebras for the generation of primordial perturbations from slow-roll inflation. Specifically, we assume that the quantum commutator of the inflaton's amplitude and momentum in Fourier space gets modified at energies above some threshold M{sub *}. We show that when the commutator is modified to be a function of the momentum only, the problem of solving for the post-inflationary spectrum of fluctuations is formally equivalent to solving a one-dimensional Schr and quot;odinger equation with a time dependent potential. Depending on the class of modification, we find results either close to or significantly different from nearly scale invariant spectra. For the former case, the power spectrum is characterized by step-like behaviour at some pivot scale, where the magnitude of the jump is O(H{sup 2}/M{sub *}{sup 2}). (H is the inflationary Hubble parameter.) We use our calculated power spectra to generate predictions for the cosmic microwave background and baryon acoustic oscillations, hence demonstrating that certain types of deformations are incompatible with current observations.

  1. Short wavelength topography on the inner-core boundary

    E-Print Network [OSTI]

    Cao, A.; Masson, Y.; Romanowicz, B.

    2006-01-01

    Short wavelength topography on the inner-core boundary Aimin94720 Constraining the topography of the inner-core boundaryindicates the presence of topography at the inner- core

  2. Contractional deformation of porous sandstone: Insights from the Aztec Sandstone, SE Nevada, USA

    E-Print Network [OSTI]

    Fossen, Haakon

    Contractional deformation of porous sandstone: Insights from the Aztec Sandstone, SE Nevada, USA Available online 19 March 2015 Keywords: Sevier thrusting Porous sandstone deformation Deformation bands Contractional deformation a b s t r a c t Contractional deformation of highly porous sandstones is poorly

  3. Generator stator core vent duct spacer posts

    DOE Patents [OSTI]

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

    2003-06-24

    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.

  4. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit the followingConcentratingPortalCool MagneticCopper Palladium-Core

  5. 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoopButtePower Ventures JumpCommercialRenewableGlobal LInformationCore Analysis

  6. Core refueling subsystem design description. Revision 1

    SciTech Connect (OSTI)

    Anderson, J.K.; Harvey, E.C.

    1987-07-01

    The Core Refueling Subsystem of the Fuel Handling and Storage System provides the mechanisms and tools necessary for the removal and replacement of the hexagonal elements which comprise the reactor core. The Core Refueling Subsystem is not "safety-related." The Core Refueling Subsystem equipment is used to prepare the plant for element removal and replacement, install the machines which handle the elements, maintain control of air inleakage and radiation release, transport the elements between the core and storage, and control the automatic and manual operations of the machines. Much of the element handling is performed inside the vessel, and the entire exchange of elements between storage and core is performed with the elements in a helium atmosphere. The core refueling operations are conducted with the reactor module shutdown and the primary coolant pressure slightly subatmospheric. The subsystem is capable of accomplishing the refueling in a reliable manner commensurate with the plant availability requirements.

  7. Plastic deformation in Al (Cu) interconnects stressed by electromigration and studied by synchrotron polychromatic X-ray microdiffraction

    E-Print Network [OSTI]

    Chen, Kai; Advanced Light Source; UCLA

    2008-01-01

    Plastic deformation in Al (Cu) interconnects stressed bygrain orientation [7], study plastic deformation [12-15] andThis aspect of EM-induced plastic deformation in grains

  8. Deformation during casting of steel: model and material C. Beckermann

    E-Print Network [OSTI]

    Beckermann, Christoph

    Deformation during casting of steel: model and material properties C. Monroe C. Beckermann Dimensional differences between a final casting and its design are casting distortions. Distortion is created by the deformation occurring throughout solidification and further cooling during the casting process. Accurate

  9. An experimental study on grain deformation and interactions in an

    E-Print Network [OSTI]

    Tong, Wei

    deformation; B. Crystal plasticity International Journal of Plasticity 20 (2004) 523­542 www knowledge on the plasticity of single crystals, the plastic deformation behavior of a polycrystalline of crystal plasticity while the computational costs are increasingly affordable (Barbe et al., 2001; Goh et

  10. Local Deformations of Polymers with Nonplanar Rigid Main-Chain

    E-Print Network [OSTI]

    Dinner, Aaron

    Local Deformations of Polymers with Nonplanar Rigid Main-Chain Internal Coordinates AARON R. DINNER: A procedure for local deformation of a polymer by concerted rotation of several main-chain dihedral angles has of an RNA hairpin loop in which the main chain (C3 --C4 ) bonds that are constrained by the sugar rings

  11. Seismology of plastic deformation Jero^me Weiss *, Francois Louchet

    E-Print Network [OSTI]

    Weiss, Jérôme

    Seismology of plastic deformation Je´ro^me Weiss *, Franc¸ois Louchet Laboratoire de Glaciologie et-free critical picture of dislocational plasticity that challenges the classical continuum models of plasticity rights reserved. Keywords: Acoustic methods; Dislocation dynamics; Plastic deformation; Self

  12. Micrographic detection of plastic deformation in nickel base alloys

    DOE Patents [OSTI]

    Steeves, Arthur F. (Schenectady, NY); Bibb, Albert E. (Clifton Park, NY)

    1984-01-01

    A method for detecting low levels of plastic deformation in metal articles comprising electrolytically etching a flow free surface of the metal article with nital at a current density of less than about 0.1 amp/cm.sup.2 and microscopically examining the etched surface to determine the presence of alternating striations. The presence of striations indicates plastic deformation in the article.

  13. Medially Based Meshing with Finite Element Analysis of Prostate Deformation

    E-Print Network [OSTI]

    Crouch, Jessica R.

    Medially Based Meshing with Finite Element Analysis of Prostate Deformation Jessica R. Crouch1 have approached prostate imaging problems using meth- ods that incorporate finite element analysis. Assume the prostate is a linearly elastic body and compute its deformation using finite element analysis

  14. Large Deformation of Nitinol Under Shear Dominant Loading

    E-Print Network [OSTI]

    Bhattacharya, Kaushik

    Large Deformation of Nitinol Under Shear Dominant Loading S. Daly & D. Rittel & K. Bhattacharya & G Abstract Full-field quantitative strain maps of phase transformation and plasticity in Nitinol under large that is seen in uniaxial testing. The shear-dominant deformation of Nitinol in the plastic regime exhibits low

  15. Characterisation of severely deformed austenitic stainless steel wire

    E-Print Network [OSTI]

    Cambridge, University of

    . Experimental procedure Stainless steel (316L) wires with 190 mm diameter in the annealed state are usedCharacterisation of severely deformed austenitic stainless steel wire H. S. Wang1 , J. R. Yang1 of 316L austenitic stainless steel has been examined using TEM and X-ray diffraction. The deformation

  16. Skuller: A volumetric shape registration algorithm for modeling skull deformities

    E-Print Network [OSTI]

    Plotkin, Joshua B.

    Skuller: A volumetric shape registration algorithm for modeling skull deformities Yusuf Sahillioglu online 8 April 2015 Keywords: Volumetric shape registration Deformation High-resolution model a b s t r a c t We present an algorithm for volumetric registration of 3D solid shapes. In comparison

  17. DEFORMATION OF THE HURRICANE MOUNTAIN FORMATION MELANGE ALONG TOMHEGAN AND

    E-Print Network [OSTI]

    Beane, Rachel J.

    DEFORMATION OF THE HURRICANE MOUNTAIN FORMATION MELANGE ALONG TOMHEGAN AND COLD STREAMS, WEST through Acadian deformation recorded in foliated pelites of the Hurricane Mountain Formation in west central Maine. The Hurricane Mountain Formation is a melange with a grey sulfidic slate- to gneiss- matrix

  18. Representation Theory of Generalized Deformed Oscillator Algebras

    E-Print Network [OSTI]

    C. Quesne; N. Vansteenkiste

    1997-01-28

    The representation theory of the generalized deformed oscillator algebras (GDOA's) is developed. GDOA's are generated by the four operators ${1,a,a^{\\dag},N}$. Their commutators and Hermiticity properties are those of the boson oscillator algebra, except for $[a, a^{\\dag}]_q = G(N)$, where $[a,b]_q = a b - q b a$ and $G(N)$ is a Hermitian, analytic function. The unitary irreductible representations are obtained by means of a Casimir operator $C$ and the semi-positive operator $a^{\\dag} a$. They may belong to one out of four classes: bounded from below (BFB), bounded from above (BFA), finite-dimentional (FD), unbounded (UB). Some examples of these different types of unirreps are given.

  19. High stroke pixel for a deformable mirror

    DOE Patents [OSTI]

    Miles, Robin R.; Papavasiliou, Alexandros P.

    2005-09-20

    A mirror pixel that can be fabricated using standard MEMS methods for a deformable mirror. The pixel is electrostatically actuated and is capable of the high deflections needed for spaced-based mirror applications. In one embodiment, the mirror comprises three layers, a top or mirror layer, a middle layer which consists of flexures, and a comb drive layer, with the flexures of the middle layer attached to the mirror layer and to the comb drive layer. The comb drives are attached to a frame via spring flexures. A number of these mirror pixels can be used to construct a large mirror assembly. The actuator for the mirror pixel may be configured as a crenellated beam with one end fixedly secured, or configured as a scissor jack. The mirror pixels may be used in various applications requiring high stroke adaptive optics.

  20. The core legion object model

    SciTech Connect (OSTI)

    Lewis, M.; Grimshaw, A.

    1996-12-31

    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.

  1. Electric-magnetic deformations of D=4 gauged supergravities

    E-Print Network [OSTI]

    Inverso, Gianluca

    2015-01-01

    We discuss duality orbits and symplectic deformations of D=4 gauged supergravity theories, with focus on N$\\ge$2. We provide a general constructive framework for computing symplectic deformations starting from a reference gauging, and apply it to many interesting examples. We prove that no continuous deformations are allowed for Fayet-Iliopoulos gaugings of the N=2 STU model and in particular that any $\\omega$ deformation is classically trivial. We further show that although in the N=6 truncation of SO(8) maximal supergravity the $\\omega$ parameter can be dualized away, in the 'twin' N=2 truncation $\\omega$ is preserved and a second, new deformation appears. We further provide a full classification and appropriate duality orbits of certain N=4 gauged supergravities, including all inequivalent SO(4)$^2$ gaugings and several non-compact forms.

  2. EFFECT OF GRAIN SIZE ON THE ACOUSTIC EMISSION GENERATED DURING PLASTIC DEFORMATION OF COPPER

    E-Print Network [OSTI]

    Baram, J.

    2011-01-01

    but only after some extent of plastic deformation, It can,The Inhomogeneity of Plastic Deformation, A.S.M. Seminar,EMISSION GENERATED DURING PLASTIC DEFORMATION OF COPPER J,

  3. Application of spatial correlation functions in permeability estimation of deformation bands in porous rocks

    E-Print Network [OSTI]

    Fossen, Haakon

    localization structures in porous sandstones, known as deformation bands, are reported to perturb functions to estimate the porosity and specific surface area in deformed sandstones from high anisotropy with regard to petrophysical properties in deformed sandstones, and demonstrated variations

  4. Two-step liquid-solid vortex transition with the field along the ab planes in YBa2Cu3O7 crystals

    E-Print Network [OSTI]

    Grigera, Santiago

    , in the mixed state of clean and twinned YBa2Cu3O7 single crystals, support the existence of a vortex and Instituto Balseiro, Comisio´n Nacional de Energi´a Ato´mica, 8400 San Carlos de Bariloche, Argentina-smectic phase when the vortices interact with an attractive periodic potential. The transition from the vortex

  5. A vortex tube is a device of a simple structure with no moving parts that can be used to separate a compressed gas into a hot stream and a cold stream. Many studies have been

    E-Print Network [OSTI]

    A vortex tube is a device of a simple structure with no moving parts that can be used to separate of the energy separation in the vortex tube. Recent rapid development in computational fluid dynamics is providing a powerful tool to investigate the complex flow in the vortex tube. However various issues

  6. Molding the flow of light on the nanoscale: from vortex nanogears to phase-operated plasmonic machinery

    E-Print Network [OSTI]

    Boriskina, Svetlana V; 10.1039/C1NR11406A

    2011-01-01

    Efficient delivery of light into nanoscale volumes by converting free photons into localized charge-density oscillations (surface plasmons) enables technological innovation in various fields from biosensing to photovoltaics and quantum computing. Conventional plasmonic nanostructures are designed as nanoscale analogs of radioantennas and waveguides. Here, we discuss an alternative approach for plasmonic nanocircuit engineering that is based on molding the optical powerflow through 'vortex nanogears' around a landscape of local phase singularities 'pinned' to plasmonic nanostructures. We show that coupling of several vortex nanogears into transmission-like structures results in dramatic optical effects, which can be explained by invoking a hydrodynamic analogy of the 'photon fluid'. The new concept of vortex nanogear transmissions (VNTs) provides new design principles for the development of complex multi-functional phase-operated photonics machinery and, therefore, generates unique opportunities for light gene...

  7. Molding the flow of light on the nanoscale: from vortex nanogears to phase-operated plasmonic machinery

    E-Print Network [OSTI]

    Svetlana V. Boriskina; Bjoern M. Reinhard

    2011-12-07

    Efficient delivery of light into nanoscale volumes by converting free photons into localized charge-density oscillations (surface plasmons) enables technological innovation in various fields from biosensing to photovoltaics and quantum computing. Conventional plasmonic nanostructures are designed as nanoscale analogs of radioantennas and waveguides. Here, we discuss an alternative approach for plasmonic nanocircuit engineering that is based on molding the optical powerflow through 'vortex nanogears' around a landscape of local phase singularities 'pinned' to plasmonic nanostructures. We show that coupling of several vortex nanogears into transmission-like structures results in dramatic optical effects, which can be explained by invoking a hydrodynamic analogy of the 'photon fluid'. The new concept of vortex nanogear transmissions (VNTs) provides new design principles for the development of complex multi-functional phase-operated photonics machinery and, therefore, generates unique opportunities for light generation, harvesting and processing on the nanoscale.

  8. Scattering of electromagnetic waves by vortex density structures associated with interchange instability: Analytical and large scale plasma simulation results

    SciTech Connect (OSTI)

    Sotnikov, V.; Kim, T.; Lundberg, J.; Paraschiv, I.; Mehlhorn, T. A.

    2014-05-15

    The presence of plasma turbulence can strongly influence propagation properties of electromagnetic signals used for surveillance and communication. In particular, we are interested in the generation of low frequency plasma density irregularities in the form of coherent vortex structures. Interchange or flute type density irregularities in magnetized plasma are associated with Rayleigh-Taylor type instability. These types of density irregularities play an important role in refraction and scattering of high frequency electromagnetic signals propagating in the earth ionosphere, in high energy density physics, and in many other applications. We will discuss scattering of high frequency electromagnetic waves on low frequency density irregularities due to the presence of vortex density structures associated with interchange instability. We will also present particle-in-cell simulation results of electromagnetic scattering on vortex type density structures using the large scale plasma code LSP and compare them with analytical results.

  9. Meissner Effect and Vortex Dynamics in Quark Stars -- A Model for Soft Gamma-Ray Repeaters

    E-Print Network [OSTI]

    R. Ouyed; O. Elgaroy; H. Dahle; P. Keranen

    2004-03-24

    We present a new model for soft gamma-ray repeaters based on a quark star born with temperatures above the critical value (T_c) for the onset of the colour-flavor locked superconductivity. The quark star then quickly cools below T_c, expelling a fraction of the surface magnetic field via the Meissner effect. We show that if a small fraction (\\leq 10%) of the surface magnetic field (10^{14} - 10^{15} {\\rm G}) is expelled, it quickly decays via magnetic reconnection and heats up the quark star surface to temperatures > 10^9 {\\rm K}. Created (e^{+},e^{-}) pairs annihilate into gamma rays emitted in a giant burst (the first burst in our model), with a luminosity of \\sim 10^{45} {\\rm ergs} {\\rm s}^{-1}. Subsequent bursts result from the restructuring of the surface magnetic field following the formation and relaxation of a vortex lattice which confines the internal magnetic field. During this phase, energy is sporadically released as a consequence of magnetic reconnection events in the entangled surface magnetic field as it evolves into a smooth, more stable, configuration. The star eventually enters a quiescent phase in which energy is continuously supplied by vortex annihilation at the surface. As the star spins down, the outermost vortex lines will be pushed to the surface where they annihilate and release their confined magnetic field. We show that the corresponding luminosity is L_v \\sim 10^{36} {\\rm ergs} {\\rm s}^{-1} for a typical soft gamma-ray repeater spinning with a period of 8 {\\rm s} and a surface magnetic field not exceeding 10^{15} {\\rm G}. Our model can be applied to any situation where a T>T_{\\rm c} quark star is generated. We discuss the connection between anomalous X-ray pulsars and soft gamma-ray repeaters in the context of our model.

  10. Ultrasound scattering and the study of vortex correlations in disordered flows

    E-Print Network [OSTI]

    Denis Boyer; Fernando Lund

    1999-12-14

    In an idealized way, some turbulent flows can be pictured by assemblies of many vortices characterized by a set of particle distribution functions. Ultrasound provide an useful, nonintrusive, tool to study the spatial structure of vorticity in flows. This is analogous to the use of elastic neutron scattering to determine liquid structure. We express the dispersion relation, as well as the scattering cross section, of sound waves propagating in a ``liquid'' of identical vortices as a function of vortex pair correlation functions. In two dimensions, formal analogies with ionic liquids are pointed out.

  11. Extraordinary optical transmission and vortex excitation by periodic arrays of Fresnel zone plates

    E-Print Network [OSTI]

    Roszkiewicz, A

    2013-01-01

    Extraordinary optical transmission and good focusing properties of a two-dimensional scattering structure is presented. The structure is made of Fresnel zone plates periodically arranged along two orthogonal directions. Each plate consists of two ring-shaped waveguides supporting modes that match the symmetry of a circularly polarized incident plane wave. High field concentration at the focal plane is obtained with short transverse and long longitudinal foci diameters. Optical vortex excitation in a paraxial region of the transmitted field is also observed and analysed in terms of cross-polarisation coupling. The structure presented may appear useful in visualization, trapping and precise manipulations of nanoparticles.

  12. Cool Core Clusters from Cosmological Simulations

    E-Print Network [OSTI]

    Rasia, E; Murante, G; Planelles, S; Beck, A M; Biffi, V; Ragone-Figueroa, C; Granato, G L; Steinborn, L K; Dolag, K

    2015-01-01

    We present results obtained from a set of cosmological hydrodynamic simulations of galaxy clusters, aimed at comparing predictions with observational data on the diversity between cool-core and non-cool-core clusters. Our simulations include the effects of stellar and AGN feedback and are based on an improved version of the Smoothed-Particle-Hydrodynamics code GADGET-3, which ameliorates gas mixing and better captures gas-dynamical instabilities by including a suitable artificial thermal diffusion. In this Letter, we focus our analysis on the entropy profiles, our primary diagnostic to classify the degree of cool-coreness of clusters, and on the iron profiles. In keeping with observations, our simulated clusters display a variety of behaviors in entropy profiles: they range from steadily decreasing profiles at small radii, characteristic of cool-core systems, to nearly flat core isentropic profiles, characteristic of non cool-core systems. Using observational criteria to distinguish between the two classes of...

  13. Antibubbles in a cyclone eyewall

    E-Print Network [OSTI]

    Terwagne, D; Vandewalle, N; Caps, H; Dorbolo, S

    2009-01-01

    A negative bubble, coined antibubble, is composed by a thin air shell that is immersed in a soapy mixture. A large vortex is generated in the liquid using a mixer. An antibubble is then created close to the surface. The antibubble is fastly attracted by the vortex. It rotates arount the core and comes closer and closer. When the stress is large enough, the vortex deforms the antibubble that winds around the eye vortex. The antibubble looks like a spiral. Under some conditions, the antibubble splits into several antibubbles that are ejected out of the eye vortex while the largest part is still trapped the vortex. This latter is elongated and is absorbed to the bottom of the tank before popping. fluid dynamics video

  14. Revised 60-day safety screening and ferrocyanide results for tank 241-BY-108, rotary samples core 98 and core 104

    SciTech Connect (OSTI)

    Baldwin, J.H.

    1996-02-01

    Revised Report for 60-Day Safety Screening Results, Rotary Samples Core 98 and Core 104, Safety Screening and Ferrocyanide Results.

  15. Critical current density and mechanism of vortex pinning in KxFe2-ySe? doped with S

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

    Lei, Hechang; Petrovic, C.

    2011-08-01

    We report the critical current density Jc in KxFe2-ySe2-zSz crystals. The Jc can be enhanced significantly with optimal S doping (z=0.99). For K0.70(7)Fe1.55(7)Se1.01(2)S0.99(2), the weak fishtail effect is found for H II c. The normalized vortex pinning forces follow the scaling law with a maximum position at 0.41 of the reduced magnetic field. These results demonstrate that the small size normal point defects dominate the vortex pinning mechanism.

  16. Thermally Stable Nanocatalyst for High Temperature Reactions: Pt-Mesoporous Silica Core-Shell Nanoparticles

    SciTech Connect (OSTI)

    Joo, Sang Hoon; Park, J.Y.; Tsung, C.-K.; Yamada, Y.; Yang, P.; Somorjai, G.A.

    2008-10-25

    Recent advances in colloidal synthesis enabled the precise control of size, shape and composition of catalytic metal nanoparticles, allowing their use as model catalysts for systematic investigations of the atomic-scale properties affecting catalytic activity and selectivity. The organic capping agents stabilizing colloidal nanoparticles, however, often limit their application in high-temperature catalytic reactions. Here we report the design of a high-temperature stable model catalytic system that consists of Pt metal core coated with a mesoporous silica shell (Pt{at}mSiO{sub 2}). While inorganic silica shells encaged the Pt cores up to 750 C in air, the mesopores directly accessible to Pt cores made the Pt{at}mSiO{sub 2} nanoparticles as catalytically active as bare Pt metal for ethylene hydrogenation and CO oxidation. The high thermal stability of Pt{at}mSiO{sub 2} nanoparticles permitted high-temperature CO oxidation studies, including ignition behavior, which was not possible for bare Pt nanoparticles because of their deformation or aggregation. The results suggest that the Pt{at}mSiO{sub 2} nanoparticles are excellent nanocatalytic systems for high-temperature catalytic reactions or surface chemical processes, and the design concept employed in the Pt{at}mSiO{sub 2} core-shell catalyst can be extended to other metal-metal oxide compositions.

  17. 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)

    2011-11-15

    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.

  18. December 2011 | 41 Suspended Core Subwavelength

    E-Print Network [OSTI]

    Skorobogatiy, Maksim

    fabricated a polyethylene microstructured fiber featuring a subwavelength-size core suspended by very thin shielded from the environment. e experimental modal field distributions were also well reproduced

  19. Relativistic Hartree-Fock-Bogoliubov model for deformed nuclei

    SciTech Connect (OSTI)

    Ebran, J.-P.; Khan, E.; Pena Arteaga, D.; Vretenar, D.

    2011-06-15

    The relativistic Hartree-Fock-Bogoliubov model for axially deformed nuclei (RHFBz) is introduced. The model is based on an effective Lagrangian with density-dependent meson-nucleon couplings in the particle-hole channel, and the central part of the Gogny force is used in the pairing channel. The RHFBz quasiparticle equations are solved by expansion in the basis of a deformed harmonic oscillator. Illustrative RHFBz calculations are performed for carbon, neon, and magnesium isotopes. The effect of explicitly including the pion field is investigated for binding energies, deformation parameters, and charge radii and has an impact on the nuclei's shape.

  20. Venturi/vortex scrubber technology for controlling/recycling chromium electroplating emissions. Final report

    SciTech Connect (OSTI)

    Hay, K.J.; Qi, S.; Holden, B.; Helgeson, N.; Fraser, M.E.

    1999-03-01

    Chromium electroplating is an essential DOD process. Chromium has a combination of qualities that are very difficult to substitute, however, the process itself is inefficient, resulting in the production of byproduct gases that rise and create a mist of chromic acid (strongly regulated as an air pollutant) above the plating tank. Venturi/Vortex Scrubber Technology (VVST) was designed to control chromium electroplating emissions by collecting the gas bubbles before they burst at the solution`s surface. This project demonstrated the Venturi/Vortex Scrubber Technology at the Marine Corps Logistics Base (MCLB) in Albany, GA. This study concluded that the PLRS was able to reduce the flow rate of the current conventional ventilation system at the one tank chromium electroplating facility at MCLB Albany by 63 percent. If new ventilation and control equipment were to be installed at MCLB Albany, this system would offer a 25 percent reduction in capital costs and a 48 percent reduction in annual costs, representing 36 percent in life-cycle cost savings. This study also presented a strong case for the use of Spark-Induced Breakdown Spectroscopy for monitoring real-time chromium emissions above a chromium electroplating tank.

  1. MAP, MAC, and Vortex-rings Configurations in the Weinberg-Salam Model

    E-Print Network [OSTI]

    Rosy Teh; Ban-Loong Ng; Khai-Ming Wong

    2015-03-20

    We report on the presence of new axially symmetric monopoles, antimonopoles and vortex-rings solutions of the SU(2)$\\times$U(1) Weinberg-Salam model of electromagnetic and weak interactions. When the $\\phi$-winding number $n=1$, and 2, the configurations are monopole-antimonopole pair (MAP) and monopole-antimonopole chain (MAC) with poles of alternating sign magnetic charge arranged along the $z$-axis. Vortex-rings start to appear from the MAP and MAC configurations when the winding number $n=3$. The MAP configurations possess zero net magnetic charge whereas the MAC configurations possess net magnetic charge of $4\\pi n/e$. In the MAP configurations, the monopole-antimonopole pair is bounded by the ${\\cal Z}^0$ field flux string and there is an electromagnetic current loop encircling it. The monopole and antimonopole possess magnetic charges $\\pm\\frac{4\\pi n}{e}\\sin^2\\theta_W$ respectively. In the MAC configurations there is no string connecting the monopole and the adjacent antimonopole and they possess magnetic charges $\\pm\\frac{4\\pi n}{e}$ respectively. The MAC configurations possess infinite total energy and zero magnetic dipole moment whereas the MAP configurations which are actually sphalerons possess finite total energy and magnetic dipole moment. The configurations were investigated for varying values of Higgs self-coupling constant $0\\leq \\lambda\\leq 40$ at Weinberg angle $\\theta_W=\\frac{\\pi}{4}$.

  2. Vortex and structural dynamics of a flexible cylinder in cross-flow

    SciTech Connect (OSTI)

    Shang, Jessica K., E-mail: jshang@princeton.edu; Stone, Howard A. [Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544 (United States); Smits, Alexander J. [Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544 (United States); Monash University, VIC 3800 (Australia)

    2014-05-15

    A low-density, flexible cantilevered cylinder was permitted to vibrate freely under the influence of vortex shedding in the laminar flow regime. We find that the vortex-induced vibrations (VIV) of a flexible cantilever depart from those of a flexible cylinder that is fixed at both ends. In particular, we find discontinuous regions of VIV behavior – here called states – as a function of the reduced velocity U{sup *}. These states are demarcated by discrete changes in the dominant eigenmodes of the structural response as the cylinder vibrates in progressively higher structural modes with increasing U{sup *}. The contribution of structural modes can be identified readily by a modal projection of the cylinder oscillation onto known cantilever beam modes. Oscillation frequencies do not monotonically increase with U{sup *}. The wake response between different states is also found to have distinct characteristics; of particular note is the occurrence of a P+S wake over one of these regions, which is associated with a high-amplitude vibration of the cylinder that is due to the constructive interference of contributing eigenmodes.

  3. Direct femtosecond laser ablation of copper with an optical vortex beam

    SciTech Connect (OSTI)

    Anoop, K. K.; Rubano, A.; Marrucci, L.; Bruzzese, R.; Amoruso, S., E-mail: amoruso@na.infn.it [Dipartimento di Fisica, Università di Napoli Federico II, Complesso Universitario di Monte S. Angelo, Via Cintia, I-80126 Napoli (Italy); CNR-SPIN, UOS Napoli, Complesso Universitario di Monte S. Angelo, Via Cintia, I-80126 Napoli (Italy); Fittipaldi, R.; Vecchione, A. [CNR-SPIN, UOS Salerno, Via Giovanni Paolo II 132, I-84084 Fisciano (Italy); Wang, X.; Paparo, D. [CNR-SPIN, UOS Napoli, Complesso Universitario di Monte S. Angelo, Via Cintia, I-80126 Napoli (Italy)

    2014-09-21

    Laser surface structuring of copper is induced by laser ablation with a femtosecond optical vortex beam generated via spin-to-orbital conversion of the angular momentum of light by using a q-plate. The variation of the produced surface structures is studied as a function of the number of pulses, N, and laser fluence, F. After the first laser pulse (N=1), the irradiated surface presents an annular region characterized by a corrugated morphology made by a rather complex network of nanometer-scale ridges, wrinkles, pores, and cavities. Increasing the number of pulses (21000) and a deep crater is formed. The nanostructure variation with the laser fluence, F, also evidences an interesting dependence, with a coarsening of the structure morphology as F increases. Our experimental findings demonstrate that direct femtosecond laser ablation with optical vortex beams produces interesting patterns not achievable by the more standard beams with a Gaussian intensity profile. They also suggest that appropriate tuning of the experimental conditions (F, N) can allow generating micro- and/or nano-structured surface for any specific application.

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

    E-Print Network [OSTI]

    Frey, Jesse C.

    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

  5. 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

  6. 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

  7. 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 plan, per the planning document. Last campus strategic plan was developed in 1996. b. Provost J. Britz

  8. Module Handbook Core Univ. of Oldenburg

    E-Print Network [OSTI]

    Habel, Annegret

    /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 Technology Wind Energy Conversion (Lab) Excursion Tutorial Study Semester: First Semester Module

  9. Core sampling system spare parts assessment

    SciTech Connect (OSTI)

    Walter, E.J.

    1995-04-04

    Soon, there will be 4 independent core sampling systems obtaining samples from the underground tanks. It is desirable that these systems be available for sampling during the next 2 years. This assessment was prepared to evaluate the adequacy of the spare parts identified for the core sampling system and to provide recommendations that may remediate overages or inadequacies of spare parts.

  10. 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-REGION SLAB REACTOR MODEL CARL SUNDE,* CHRISTOPHE DEMAZIÈRE, and IMRE PÁZSIT Chalmers University of Technology. 5 gives a self-contained description of the principles of fluctuation analysis for the diagnostics

  11. Method and apparatus for recovering unstable cores

    DOE Patents [OSTI]

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

    1983-01-01

    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.

  12. Moving core beam energy absorber and converter

    DOE Patents [OSTI]

    Degtiarenko, Pavel V.

    2012-12-18

    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.

  13. Activation of conductive pathways via deformation-induced instabilities

    E-Print Network [OSTI]

    Ni, Xinchen

    2014-01-01

    Inspired by the pattern transformation of periodic elastomeric cellular structures, the purpose of this work is to exploit this unique ability to activate conductive via deformation-induced instabilities. Two microstructural ...

  14. Origin and deformation of Holocene shoreline terraces, Yellowstone Lake, Wyoming

    SciTech Connect (OSTI)

    Meyer, G.A.; Locke, W.W.

    1986-08-01

    Geodetic surveys within the Yellowstone caldera have documented active uplift that is most likely caused by magmatic processes in the upper crust. Along the northeast shore of Yellowstone Lake, maximum relative uplift rates are 10 mm/yr for the period 1923-1975. However, information on deformation prior to historic instrumental records has been lacking. In this study, closely spaced data on elevations of postglacial shoreline terraces around the north end of Yellowstone Lake reveal complex tilting. Though most Holocene deformation is probably magma related, the pattern of shoreline tilting deviates significantly from the historic pattern of roughly symmetric inflation of the caldera. Along the northeast shore, where tilt directions of historic and shoreline deformation are similar, differential uplift of a > 2500-yr-old terrace is roughly 10 m; this gives a maximum uplift rate of 4 mm/yr. These unique Holocene terraces may exist due to episodic deformation because vertical movements affecting the lake outlet directly control lake level.

  15. A Four-Dimensional Viscoelastic Deformation Model For Long Valley...

    Open Energy Info (EERE)

    1995 And 2000 Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: A Four-Dimensional Viscoelastic Deformation Model For Long Valley Caldera,...

  16. Applications of Slattery - Lagoudas' theory for the stress deformation behavior 

    E-Print Network [OSTI]

    Tian, Yongzhe

    2006-10-30

    The thermodynamics of three-dimensional, single-component elastic crystalline solids was developed by Slattery and Lagoudas (2005). Considering the in�¯nitesimal deformations, the stress can be expressed as a function of the lattice vectors...

  17. Non-linear viscoelastic deformation of polymeric solutions 

    E-Print Network [OSTI]

    Sanchez Reyes, Javier

    2000-01-01

    The dynamics of entangled polymeric solutions were studied using drag of borosilicate discs and conventional shear rheometry devices in order to understand the effect of deformation on the relaxation process and the possible ...

  18. Self-sorting of deformable particles in a microfluidic circuit

    E-Print Network [OSTI]

    Raafat, Mohamed Salem

    2010-01-01

    In this thesis, a new microfluidic device is presented for sorting of deformable particles based on the hydrodynamic resistance induced in a microchannel. Hydrodynamic resistance can be related to physical properties, ...

  19. Mechanics of inelastic deformation and delamination in paperboard

    E-Print Network [OSTI]

    Xia, Qingxi, 1973-

    2002-01-01

    Paperboard is one of the most widely used materials. The inelastic deformation of paperboard plays a crucial role during many manufacturing processes (e.g., the converting process whereby paperboard is converted into a ...

  20. 3D deformation field throughout the interior of materials.

    SciTech Connect (OSTI)

    Jin, Huiqing; Lu, Wei-Yang

    2013-09-01

    This report contains the one-year feasibility study for our three-year LDRD proposal that is aimed to develop an experimental technique to measure the 3D deformation fields inside a material body. In this feasibility study, we first apply Digital Volume Correlation (DVC) algorithm to pre-existing in-situ Xray Computed Tomography (XCT) image sets with pure rigid body translation. The calculated displacement field has very large random errors and low precision that are unacceptable. Then we enhance these tomography images by setting threshold of the intensity of each slice. DVC algorithm is able to obtain accurate deformation fields from these enhanced image sets and the deformation fields are consistent with the global mechanical loading that is applied to the specimen. Through this study, we prove that the internal markers inside the pre-existing tomography images of aluminum alloy can be enhanced and are suitable for DVC to calculate the deformation field throughout the material body.

  1. Wavefront control in space with MEMS deformable mirrors

    E-Print Network [OSTI]

    Cahoy, Kerri

    To meet the high contrast requirement of 1 × 10[superscript ?10] to image an Earth-like planet around a Sun-like star, space telescopes equipped with coronagraphs require wavefront control systems. Deformable mirrors (DMs) ...

  2. Seismic tomography and surface deformation in Krýsuvík, SW Iceland

    E-Print Network [OSTI]

    Lu, Jing, S.M. Massachusetts Institute of Technology

    2013-01-01

    The Krýsuvík region of southwestern Iceland is a region of high potential for geothermal energy that is currently experiencing seismic swarm activity and active surface deformation. Understanding the subsurface structure ...

  3. Kinematic models of interseismic deformation in Southern California

    E-Print Network [OSTI]

    Meade, Brendan J. (Brendan Joseph), 1975-

    2004-01-01

    We develop a framework for interpreting geodetic measurements of interseismic deformation and geologic slip rate estimates in terms of block motions. This method accounts for the effects of block rotations and interseismic ...

  4. Coupled heat conduction and deformation in a viscoelastic composite cylinder 

    E-Print Network [OSTI]

    Shah, Sneha

    2010-01-16

    Engineering iii ABSTRACT Coupled Heat Conduction and Deformation in a Viscoelastic Composite Cylinder. (August 2008) Sneha B. Shah, B.E., Gujarat University, India Co-Chairs of Advisory Committee: Dr. Hanifah Muliana Dr. Kumbakonam Rajagopal...

  5. 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

    2015-01-01

    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{\

  6. Effect of nuclear deformation on double beta decay

    SciTech Connect (OSTI)

    Rodin, Vadim [Institute fuer Theoretische Physik der Universitaet Tuebingen, D-72076 Tuebingen (Germany)

    2009-11-09

    The existing ways of accounting for deformation in recent calculations of neutrinoless double beta decay matrix elements are discussed. From an analysis of relevant experimental data it is argued that only {sup 150}Nd reveals convincing evidences of strong static deformation, which should eventually be taken into account in QRPA calculations. A proposal which allows in principle to measure the neutrino less double beta decay Fermi matrix element is briefly described.

  7. Structure and deformation mechanisms along the Tonale Line, n. Italy 

    E-Print Network [OSTI]

    Welker, Mary Clare

    1985-01-01

    of brittle and ductile deformation and for evidence of pore fluids. Synthesis of the field relationships, compositional and petrofabric analyses were carried out to characterize the overall structure, deformation mechanisms and mechanical behavior... whole were leveled down to a chain of fairly low hill s (Tr'umpy, 1973). Currently, the Tonale Line shows no movement, and it is seismically inactive. Both vertical and horizontal displacements are recognized along the fault, most likely from...

  8. Experimental deformation of multilithologic specimens simulating sedimentary facies changes 

    E-Print Network [OSTI]

    Dyke, Lawrence Dana

    1976-01-01

    EXPERIMENTAL DEFORMATION OF MULTILITHOLOGIC SPECIMENS SIMULATING SEDIMENTARY FACIES CHANGES A Thesis by LAWRENCE DANA DYKE Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE December 1976 Major Subject: Geology EXPERIMENTAL DEFORMATION OF MULTILITHOLOGIC SPECIMENS SIMULATING SEDIMENTARY FACIES CHANGES A Thesis by LAWRENCE DANA DYKE Approved as to style and content by: (Chai n Committee) (Head...

  9. TDHF fusion calculations for spherical+deformed systems

    E-Print Network [OSTI]

    A. S. Umar; V. E. Oberacker

    2006-04-04

    We outline a formalism to carry out TDHF calculations of fusion cross sections for spherical + deformed nuclei. The procedure incorporates the dynamic alignment of the deformed nucleus into the calculation of the fusion cross section. The alignment results from multiple E2/E4 Coulomb excitation of the ground state rotational band. Implications for TDHF fusion calculations are discussed. TDHF calculations are done in an unrestricted three-dimensional geometry using modern Skyrme force parametrizations.

  10. A finite element method with mesh adaptivity for computing vortex states in fastrotating BoseEinstein condensates

    E-Print Network [OSTI]

    Recanati, Catherine

    A finite element method with mesh adaptivity for computing vortex states in fast­rotating Bose­Einstein Abstract Numerical computations of stationary states of fast­rotating Bose­Einstein condensates require rotation rates). Key words: Gross--Pitaevskii equation, finite element method, mesh adaptivity, Bose­Einstein

  11. 1242 JOURNAL OF LIGHTWAVE TECHNOLOGY, VOL. 20, NO. 8, AUGUST 2002 Performances of the Data Vortex Switch Architecture

    E-Print Network [OSTI]

    Bergman, Keren

    the efficient scalability of the architecture under uniform and random traffic conditions while maintaining high1242 JOURNAL OF LIGHTWAVE TECHNOLOGY, VOL. 20, NO. 8, AUGUST 2002 Performances of the Data Vortex Switch Architecture Under Nonuniform and Bursty Traffic Qimin Yang, Member, IEEE, and Keren Bergman

  12. First-Order Transition in the Magnetic Vortex Matter in Superconducting MgB2 Tuned by Disorder

    E-Print Network [OSTI]

    Boyer, Edmond

    First-Order Transition in the Magnetic Vortex Matter in Superconducting MgB2 Tuned by Disorder T such as Wigner crystals, charge density waves, magnetic bubble arrays, or vortices in type-II superconductors posi- tional correlations. Vortices in superconductors rapidly became the system of choice

  13. Vortex Nucleation in a Stirred Bose-Einstein Condensate Dissipation and turbulence in superfluid flow often involves the creation and

    E-Print Network [OSTI]

    . This observation confirms the role of discrete surface modes in vortex formation. However, when we used a tightly. The nucleation process has been a subject of much theoretical interest [1]. Experiments with Bose. These resonances were close to the frequencies of excitation for surface modes of different multipolarity

  14. Nonequilibrium dynamic phases and plastic flow of driven vortex lattices in superconductors with periodic arrays of pinning sites

    E-Print Network [OSTI]

    Nori, Franco

    of lattices as a driving force is increased. For superconducting systems, experimental work in neutron conductivity. By monitoring the moving vortex lattice, we show that these features coincide with pronounced by elastic theories. Different system parameters produce other phases, including an ordered channel flow

  15. Effect of time-dependent piston velocity program on vortex ring formation in a piston/cylinder arrangement

    E-Print Network [OSTI]

    Dabiri, John O.

    Graduate Aeronautical Laboratories and Bioengineering, California Institute of Technology, Pasadena velocity fixed. It turned out that the pinch-off was always observed to occur at a stroke ratio L time scale for the pinch-off process formation number was tested by generating vortex rings

  16. To appear in the ACM SIGGRAPH conference proceedings Filament-based smoke with vortex shedding and variational reconnection

    E-Print Network [OSTI]

    Weissmann, Steffen

    To appear in the ACM SIGGRAPH conference proceedings Filament-based smoke with vortex shedding filaments is highly attractive for the creation of special effects because it gives artists full control filaments over time. Because filaments offer a very compact description of fluid flow, real time

  17. Stationary Vortex Loops Induced by Filament Interaction and Local Pinning in a Chemical Reaction-Diffusion System

    E-Print Network [OSTI]

    Steinbock, Oliver

    Stationary Vortex Loops Induced by Filament Interaction and Local Pinning in a Chemical Reaction rings are three-dimensional excitation waves rotating around one-dimensional filament loops but curved filaments. The absence of filament motion can be explained by repulsive interaction

  18. Paper No. 2004-JSC-396 Srivilairit Identification and Analysis of Vortex-Induced Vibrations of a Drilling Riser

    E-Print Network [OSTI]

    Manuel, Lance

    of a deepwater drilling riser. We examine such data from the monitoring of riser accelerations and vortex a deepwater drilling riser. The site has a water depth of 1,000 meters. These riser acceleration data consist of a Drilling Riser using Empirical and Spectral Procedures Tanapat Srivilairit and Lance Manuel Department

  19. Angularly Deformed Special Relativity and its Results for Quantum Mechanics

    E-Print Network [OSTI]

    Lukasz Andrzej Glinka

    2015-09-15

    In this paper, the deformed Special Relativity, which leads to an essentially new theoretical context of quantum mechanics, is presented. The formulation of the theory arises from a straightforward analogy with the Special Relativity, but its foundations are laid through the hypothesis on breakdown of the velocity-momentum parallelism which affects onto the Einstein equivalence principle between mass and energy of a relativistic particle. Furthermore, the derivation is based on the technique of an eikonal equation whose well-confirmed physical role lays the foundations of both optics and quantum mechanics. As a result, we receive the angular deformation of Special Relativity which clearly depicts the new deformation-based theoretical foundations of physics, and, moreover, offers both constructive and consistent phenomenological discussion of the theoretical issues such like imaginary mass and formal superluminal motion predicted in Special Relativity for this case. In the context of the relativistic theory, presence of deformation does not break the Poincar\\'{e} invariance, in particular the Lorentz symmetry, and provides essential modifications of both bosons described through the Klein-Gordon equation and fermions satisfying the Dirac equation. On the other hand, on the level of discussion of quantum theory, there arises the concept of emergent deformed space-time, wherein the presence of angular deformation elucidates a certain new insight into the nature of spin, as well as both the Heisenberg uncertainty principle and the Schr\\"odinger wave equation.

  20. Size effects on the onset of plastic deformation during nanoindentation of thin films and patterned lines

    E-Print Network [OSTI]

    Van Vliet, Krystyn J.

    Size effects on the onset of plastic deformation during nanoindentation of thin films and patterned; accepted 13 August 2003 Plastic deformation of materials exhibits a strong size dependence when, particularly the transition from elastic to plastic deformation and the early stages of plastic deformation. We

  1. Application Of Multilayer Piezoelectric Elements For Resonant Cavity Deformation In VUV-FEL DESY Accelerator

    E-Print Network [OSTI]

    Napieralski, A

    2005-01-01

    Application Of Multilayer Piezoelectric Elements For Resonant Cavity Deformation In VUV-FEL DESY Accelerator

  2. Development of venturi/vortex scrubber technology for controlling chromium electroplating hazardous air emissions. Final report

    SciTech Connect (OSTI)

    Hay, K.J.; Qi, S.; Northrup, J.I.; Heck, S.R.

    1998-07-01

    Chromium has a combination of qualities that give chromium electroplating an important role in coating military hardware and armament. However, chromium electroplating and chromium anodizing operations create hazardous air pollutants in the form of hexavalent chromium. Conventional technologies for controlling this pollutant are expensive, noisy, and use a lot of energy and water. Consequently, an air pollution problem is turned into a water pollution problem that also requires treatment. There is a need for an economical control option that pollutes less than conventional technologies. This project developed control technologies to effectively and economically control hazardous air emissions from Army chromium electroplating and anodizing operations, primarily focusing on the development of the Venturi/Vortex Scrubber technology (VVST).

  3. Non-Diffracting Electron Vortex Beams Balancing Their Electron-Electron Interactions

    E-Print Network [OSTI]

    Maor Mutzafi; Ido Kaminer; Gal Harari; Mordechai Segev

    2015-10-10

    By introducing concepts of beam shaping into quantum mechanics, we show how interference effects of the quantum wavefunction describing multiple electrons can exactly balance the repulsion among the electrons. With proper shaping of the fermionic wavefunction, we propose non-diffracting quantum wavepackets of multiple electrons that can also carry orbital angular momentum, in the form of multi-electron non-diffracting vortex beams. The wavefunction is designed to compensate for both the repulsion between electrons and for the diffraction-broadening. This wavefunction shaping facilitates the use of electron beams of higher current in numerous applications, thereby improving the signal-to-noise-ratio in electron microscopy and related systems without compromising on the spatial resolution. Our scheme potentially applies for any beams of charged particles, such as protons, muons and ion beams.

  4. Vortex Zero Modes, Large Flux Limit and Ambjørn-Nielsen-Olesen Magnetic Instabilities

    E-Print Network [OSTI]

    Stefano Bolognesi; Chandrasekhar Chatterjee; Sven Bjarke Gudnason; Kenichi Konishi

    2014-09-23

    In the large flux limit vortices become flux tubes with almost constant magnetic field in the interior region. This occurs in the case of non-Abelian vortices as well, and the study of such configurations allows us to reveal a close relationship between vortex zero modes and the gyromagnetic instabilities of vector bosons in a strong background magnetic field discovered by Nielsen, Olesen and Ambj{\\o}rn. The BPS vortices are exactly at the onset of this instability, and the dimension of their moduli space is precisely reproduced in this way. We present a unifying picture in which, through the study of the linear spectrum of scalars, fermions and W bosons in the magnetic field background, the expected number of translational, orientational, fermionic as well as semilocal zero modes is correctly reproduced in all cases.

  5. Analytic treatment of vortex states in cylindrical superconductors in applied axial magnetic field

    SciTech Connect (OSTI)

    Ludu, A.; Van Deun, J.; Cuyt, A.; Milosevic, M. V.; Peeters, F. M.

    2010-08-15

    We solve the linear Ginzburg-Landau (GL) equation in the presence of a uniform magnetic field with cylindrical symmetry and we find analytic expressions for the eigenfunctions in terms of the confluent hypergeometric functions. The discrete spectrum results from an implicit equation associated to the boundary conditions and it is resolved in analytic form using the continued fractions formalism. We study the dependence of the spectrum and the eigenfunctions on the sample size and the surface conditions for solid and hollow cylindrical superconductors. Finally, the solutions of the nonlinear GL formalism are constructed as expansions in the linear GL eigenfunction basis and selected by minimization of the free energy. We present examples of vortex states and their energies for different samples in enhancing/suppressing superconductivity surroundings.

  6. Vortex precession frequency and its amplitude-dependent shift in cylindrical nanomagnets

    SciTech Connect (OSTI)

    Metlov, Konstantin L.

    2013-12-14

    Frequency of free magnetic vortex precession in circular soft ferromagnetic nano-cylinders (magnetic dots) of various sizes is an important parameter, used in design of spintronic devices (such as spin-torque microwave nano-oscillators) and characterization of magnetic nanostructures. Here, using a recently developed collective-variable approach to non-linear dynamics of magnetic textures in planar nano-magnets, this frequency and its amplitude-dependent shift are computed analytically and plotted for the full range of cylinder geometries. The frequency shift is positive in large planar dots, but becomes negative in smaller and more elongated ones. At certain dot dimensions, a zero frequency shift is realized, which can be important for enhancing frequency stability of magnetic nano-oscillators.

  7. Optimization of vortex pinning by nanoparticles using simulations of time-dependent Ginzburg-Landau model

    E-Print Network [OSTI]

    A. E. Koshelev; I. A. Sadovskyy; C. L. Phillips; A. Glatz

    2015-10-01

    Introducing nanoparticles into superconducting materials has emerged as an efficient route to enhance their current-carrying capability. We address the problem of optimizing vortex pinning landscape for randomly distributed metallic spherical inclusions using large-scale numerical simulations of time-dependent Ginzburg-Landau equations. We found the size and density of particles for which the highest critical current is realized in a fixed magnetic field. For each particle size and magnetic field, the critical current reaches a maximum value at a certain particle density, which typically corresponds to 15-23% of the total volume being replaced by nonsuperconducting material. For fixed diameter, this optimal particle density increases with the magnetic field. Moreover, we found that the optimal particle diameter slowly decreases with the magnetic field from 4.5 to 2.5 coherence lengths at a given temperature. This result shows that pinning landscapes have to be designed for specific applications taking into account relevant magnetic field scales.

  8. Optimized focal and pupil plane masks for vortex coronagraphs on telescopes with obstructed apertures

    E-Print Network [OSTI]

    Ruane, Garreth J; Huby, Elsa; Mawet, Dimitri; Delacroix, Christian; Carlomagno, Brunella; Piron, Pierre; Swartzlander, Grover A

    2015-01-01

    We present methods for optimizing pupil and focal plane optical elements that improve the performance of vortex coronagraphs on telescopes with obstructed or segmented apertures. Phase-only and complex masks are designed for the entrance pupil, focal plane, and the plane of the Lyot stop. Optimal masks are obtained using both analytical and numerical methods. The latter makes use of an iterative error reduction algorithm to calculate "correcting" optics that mitigate unwanted diffraction from aperture obstructions. We analyze the achieved performance in terms of starlight suppression, contrast, off-axis image quality, and chromatic dependence. Manufacturing considerations and sensitivity to aberrations are also discussed. This work provides a path to joint optimization of multiple coronagraph planes to maximize sensitivity to exoplanets and other faint companions.

  9. Vortex Lattice Studies in CeCoIn? with H?c

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

    Das, P.; White, J. S.; Holmes, A. T.; Gerber, S.; Forgan, E. M.; Bianchi, A. D.; Kenzelmann, M.; Zolliker, M.; Gavilano, J. L.; Bauer, E. D.; et al

    2012-02-01

    We present small angle neutron scattering studies of the vortex lattice (VL) in CeCoIn? with magnetic fields applied parallel (H) to the antinodal [100] and nodal [110] directions. For H II 100], a single VL orientation is observed, while a 90° reorientation transition is found for H II [110]. For both field orientations and VL configurations we find a distorted hexagonal VL with an anisotropy, ?=2.0±0.05. The VL form factor shows strong Pauli paramagnetic effects similar to what have previously been reported for H II [001]. At high fields, above which the upper critical field (Hc2) becomes a first-order transition,more »an increased disordering of the VL is observed.« less

  10. Bounds on topological Abelian string-vortex and string-cigar from information-entropic measure

    E-Print Network [OSTI]

    Correa, R A C; Almeida, C A S; da Rocha, Roldao

    2016-01-01

    In this work we obtain bounds on topological Abelian string-vortex in six dimensions using a new measure of configurational complexity known as configurational entropy. In this way, the information-theoretical measure of six dimensional braneworlds scenarios are capable to probe situations where the parameters responsible for the thickness are arbitrary. The so-called Configurational Entropy (CE) selects the best value of the parameter in the model. This is accomplished by minimizing the CE, namely, by selecting the most appropriate parameters in the model that correspond to the most organized system, based upon Shannon information theory. This information-theoretical measure of complexity provides a complementary perspective to situations where strictly energy-based arguments are inconclusive. We show that the higher the energy the higher the configurational entropy, what shows an important correlation between the energy of the a localized field configuration and its associated entropic measure.

  11. Analytical description of high-aperture STED resolution with 0-2$\\pi$ vortex phase modulation

    E-Print Network [OSTI]

    Xie, Hao; Jin, Dayong; Xi, Peng

    2013-01-01

    Stimulated emission depletion (STED) can achieve optical super-resolution, with the optical diffraction limit broken by the suppression on the periphery of the fluorescent focal spot. Previously, it is generally experimentally accepted that there exists an inverse square root relationship with the STED power and the resolution, yet without strict analytical description. In this paper, we have analytically verified the relationship between the STED power and the achievable resolution from vector optical theory for the widely used 0-2$\\pi$ vortex phase modulation. Electromagnetic fields of the focal region of a high numerical aperture objective are calculated and approximated into polynomials, and analytical expression of resolution as a function of the STED intensity has been derived. As a result, the resolution can be estimated directly from the measurement of the saturation power of the dye and the STED power applied.

  12. Method for the detection of a magnetic field utilizing a magnetic vortex

    DOE Patents [OSTI]

    Novosad, Valentyn (Chicago, IL); Buchanan, Kristen (Batavia, IL)

    2010-04-13

    The determination of the strength of an in-plane magnetic field utilizing one or more magnetically-soft, ferromagnetic member, having a shape, size and material whereas a single magnetic vortex is formed at remanence in each ferromagnetic member. The preferred shape is a thin circle, or dot. Multiple ferromagnetic members can also be stacked on-top of each other and separated by a non-magnetic spacer. The resulting sensor is hysteresis free. The sensor's sensitivity, and magnetic saturation characteristics may be easily tuned by simply altering the material, size, shape, or a combination thereof to match the desired sensitivity and saturation characteristics. The sensor is self-resetting at remanence and therefore does not require any pinning techniques.

  13. 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.

    510 Plant Disease / Vol. 97 No. 4 Etiology of Moldy Core, Core Browning, and Core Rot of Fuji Apple, and core rot of Fuji apple in China. Plant Dis. 97:510-516. `Fuji' apple fruit were collected in Shaanxi to species. Pathogenicity was determined by cutting apple fruit into halves and daubing spore suspensions

  14. OSCAR Parallelizing Compiler Cooperative Heterogeneous Multi-core Architecture

    E-Print Network [OSTI]

    Kasahara, Hironori

    OSCAR Parallelizing Compiler Cooperative Heterogeneous Multi-core Architecture Akihiro Hayashi, powerful parallelizing compiler for hetero- geneous multi-core architectures is expected. Furthermore, cooperative work between parallelizing compiler and hetero- geneous multi-core architectures is important

  15. Environmental impact of various kayak core materials

    E-Print Network [OSTI]

    Kirkland, David R. (David Roger)

    2008-01-01

    This thesis compares the environmental impact of fiberglass, Kevlar, carbon fiber, and cork. A kayak company is interested in using cork as a core material, and would like to claim that it is the most environmentally ...

  16. SF Bay Cores Uncovering Our Dirty Past

    E-Print Network [OSTI]

    FOR? #12;ABSOLUTELY SOMETHING #12;Sediments Tell Our History America's largest core? Even when) > SB, SPB, SUB · Alternative hypotheses?... #12;Old King Coal? U.S. Dept of Energy · Urban residential

  17. KSI's Cross Insulated Core Transformer Technology

    SciTech Connect (OSTI)

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

    2009-08-04

    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.

  18. Armor systems including coated core materials

    DOE Patents [OSTI]

    Chu, Henry S. (Idaho Falls, ID); Lillo, Thomas M. (Idaho Falls, ID); McHugh, Kevin M. (Idaho Falls, ID)

    2012-07-31

    An armor system and method involves providing a core material and a stream of atomized coating material that comprises a liquid fraction and a solid fraction. An initial layer is deposited on the core material by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is less than the liquid fraction of the stream of atomized coating material on a weight basis. An outer layer is then deposited on the initial layer by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is greater than the liquid fraction of the stream of atomized coating material on a weight basis.

  19. Armor systems including coated core materials

    DOE Patents [OSTI]

    2013-10-08

    An armor system and method involves providing a core material and a stream of atomized coating material that comprises a liquid fraction and a solid fraction. An initial layer is deposited on the core material by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is less than the liquid fraction of the stream of atomized coating material on a weight basis. An outer layer is then deposited on the initial layer by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is greater than the liquid fraction of the stream of atomized coating material on a weight basis.

  20. Fluid-driven deformation of a soft granular material

    E-Print Network [OSTI]

    Christopher W. MacMinn; Eric R. Dufresne; John S. Wettlaufer

    2015-02-24

    Compressing a porous, fluid-filled material will drive the interstitial fluid out of the pore space, as when squeezing water out of a kitchen sponge. Inversely, injecting fluid into a porous material can deform the solid structure, as when fracturing a shale for natural gas recovery. These poromechanical interactions play an important role in geological and biological systems across a wide range of scales, from the propagation of magma through the Earth's mantle to the transport of fluid through living cells and tissues. The theory of poroelasticity has been largely successful in modeling poromechanical behavior in relatively simple systems, but this continuum theory is fundamentally limited by our understanding of the pore-scale interactions between the fluid and the solid, and these problems are notoriously difficult to study in a laboratory setting. Here, we present a high-resolution measurement of injection-driven poromechanical deformation in a system with granular microsctructure: We inject fluid into a dense, confined monolayer of soft particles and use particle tracking to reveal the dynamics of the multi-scale deformation field. We find that a continuum model based on poroelasticity theory captures certain macroscopic features of the deformation, but the particle-scale deformation field exhibits dramatic departures from smooth, continuum behavior. We observe particle-scale rearrangement and hysteresis, as well as petal-like mesoscale structures that are connected to material failure through spiral shear banding.