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We encourage you to perform a real-time search of NLEBeta
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1

Magnetic Vortex Core Reversal by Low-Field Excitations  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known...

2

Magnetic Vortex Core Reversal by Low-Field Excitations  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnetic Vortex Core Reversal by 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 films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because 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 thought to be necessary to accomplish this. At the ALS, a team of researchers from Germany, Belgium, and the U.S. has used time-resolved scanning transmission x-ray microscopy (STXM) to observe vortex motion and demonstrate the feasibility of using weak magnetic fields as low as 1.5 millitesla (mT) to reverse the direction of a vortex core. The observed switching mechanism, which can be understood within the framework of micromagnetic theory, gives insights into basic magnetization dynamics and their possible application to data storage technologies.

3

Magnetic Vortex Core Reversal by Low-Field Excitations  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnetic Vortex Core Reversal by Low-Field Excitations Print Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because 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 thought to be necessary to accomplish this. At the ALS, a team of researchers from Germany, Belgium, and the U.S. has used time-resolved scanning transmission x-ray microscopy (STXM) to observe vortex motion and demonstrate the feasibility of using weak magnetic fields as low as 1.5 millitesla (mT) to reverse the direction of a vortex core. The observed switching mechanism, which can be understood within the framework of micromagnetic theory, gives insights into basic magnetization dynamics and their possible application to data storage technologies.

4

Magnetic Vortex Core Reversal by Low-Field Excitations  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnetic Vortex Core Reversal by Low-Field Excitations Print Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because 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 thought to be necessary to accomplish this. At the ALS, a team of researchers from Germany, Belgium, and the U.S. has used time-resolved scanning transmission x-ray microscopy (STXM) to observe vortex motion and demonstrate the feasibility of using weak magnetic fields as low as 1.5 millitesla (mT) to reverse the direction of a vortex core. The observed switching mechanism, which can be understood within the framework of micromagnetic theory, gives insights into basic magnetization dynamics and their possible application to data storage technologies.

5

Magnetic Vortex Core Reversal by Low-Field Excitations  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnetic Vortex Core Reversal by Low-Field Excitations Print Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because 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 thought to be necessary to accomplish this. At the ALS, a team of researchers from Germany, Belgium, and the U.S. has used time-resolved scanning transmission x-ray microscopy (STXM) to observe vortex motion and demonstrate the feasibility of using weak magnetic fields as low as 1.5 millitesla (mT) to reverse the direction of a vortex core. The observed switching mechanism, which can be understood within the framework of micromagnetic theory, gives insights into basic magnetization dynamics and their possible application to data storage technologies.

6

Low-amplitude magnetic vortex core reversal by non-linear interaction between azimuthal spin waves and the vortex gyromode  

SciTech Connect

We show, by experiments and micromagnetic simulations in vortex structures, that an active “dual frequency” excitation of both the sub-GHz vortex gyromode and multi-GHz spin waves considerably changes the frequency response of spin wave mediated vortex core reversal. Besides additional minima in the switching threshold, a significant broadband reduction of the switching amplitudes is observed, which can be explained by non-linear interaction between the vortex gyromode and the spin waves. We conclude that the well known frequency spectra of azimuthal spin waves in vortex structures are altered substantially, when the vortex gyromode is actively excited simultaneously.

Sproll, Markus; Noske, Matthias; Kammerer, Matthias; Dieterle, Georg; Weigand, Markus; Stoll, Hermann; Schütz, Gisela [Max Planck Institute for Intelligent Systems (formerly MPI for Metals Research), Heisenbergstr. 3, 70569 Stuttgart (Germany)] [Max Planck Institute for Intelligent Systems (formerly MPI for Metals Research), Heisenbergstr. 3, 70569 Stuttgart (Germany); Bauer, Hans; Gangwar, Ajay; Woltersdorf, Georg; Back, Christian H. [Department of Physics, University of Regensburg, Universitätsstr. 31, 93040 Regensburg (Germany)] [Department of Physics, University of Regensburg, Universitätsstr. 31, 93040 Regensburg (Germany)

2014-01-06T23:59:59.000Z

7

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

NLE Websites -- All DOE Office Websites (Extended Search)

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print Magnetic thin-film nanostructures can exhibit a magnetic vortex state in which the magnetization vectors lie in the film plane and curl around in a closed loop. At the very center of the vortex, a small, stable core exists where the magnetization points either up or down out of the plane. Three years ago, the discovery of an easy core reversal mechanism at the ALS not only made the possibility of using such systems as magnetic memories much more realistic, it also initiated investigation of the core switching mechanism itself. Now, a Belgian-German-ALS collaboration has used high-resolution, time-resolved, magnetic x-ray microscopy to experimentally reveal the first step of the reversal process: the dynamic deformation of the vortex core. The group also measured a critical vortex velocity above which reversal occurs. Both these observations provide the first experimental support for the postulated reversal mechanism.

8

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

NLE Websites -- All DOE Office Websites (Extended Search)

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print Magnetic thin-film nanostructures can exhibit a magnetic vortex state in which the magnetization vectors lie in the film plane and curl around in a closed loop. At the very center of the vortex, a small, stable core exists where the magnetization points either up or down out of the plane. Three years ago, the discovery of an easy core reversal mechanism at the ALS not only made the possibility of using such systems as magnetic memories much more realistic, it also initiated investigation of the core switching mechanism itself. Now, a Belgian-German-ALS collaboration has used high-resolution, time-resolved, magnetic x-ray microscopy to experimentally reveal the first step of the reversal process: the dynamic deformation of the vortex core. The group also measured a critical vortex velocity above which reversal occurs. Both these observations provide the first experimental support for the postulated reversal mechanism.

9

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

NLE Websites -- All DOE Office Websites (Extended Search)

X-Ray Imaging of the Dynamic X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print Wednesday, 25 November 2009 00:00 Magnetic thin-film nanostructures can exhibit a magnetic vortex state in which the magnetization vectors lie in the film plane and curl around in a closed loop. At the very center of the vortex, a small, stable core exists where the magnetization points either up or down out of the plane. Three years ago, the discovery of an easy core reversal mechanism at the ALS not only made the possibility of using such systems as magnetic memories much more realistic, it also initiated investigation of the core switching mechanism itself. Now, a Belgian-German-ALS collaboration has used high-resolution, time-resolved, magnetic x-ray microscopy to experimentally reveal the first step of the reversal process: the dynamic deformation of the vortex core. The group also measured a critical vortex velocity above which reversal occurs. Both these observations provide the first experimental support for the postulated reversal mechanism.

10

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

NLE Websites -- All DOE Office Websites (Extended Search)

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print Magnetic thin-film nanostructures can exhibit a magnetic vortex state in which the magnetization vectors lie in the film plane and curl around in a closed loop. At the very center of the vortex, a small, stable core exists where the magnetization points either up or down out of the plane. Three years ago, the discovery of an easy core reversal mechanism at the ALS not only made the possibility of using such systems as magnetic memories much more realistic, it also initiated investigation of the core switching mechanism itself. Now, a Belgian-German-ALS collaboration has used high-resolution, time-resolved, magnetic x-ray microscopy to experimentally reveal the first step of the reversal process: the dynamic deformation of the vortex core. The group also measured a critical vortex velocity above which reversal occurs. Both these observations provide the first experimental support for the postulated reversal mechanism.

11

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

NLE Websites -- All DOE Office Websites (Extended Search)

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print Magnetic thin-film nanostructures can exhibit a magnetic vortex state in which the magnetization vectors lie in the film plane and curl around in a closed loop. At the very center of the vortex, a small, stable core exists where the magnetization points either up or down out of the plane. Three years ago, the discovery of an easy core reversal mechanism at the ALS not only made the possibility of using such systems as magnetic memories much more realistic, it also initiated investigation of the core switching mechanism itself. Now, a Belgian-German-ALS collaboration has used high-resolution, time-resolved, magnetic x-ray microscopy to experimentally reveal the first step of the reversal process: the dynamic deformation of the vortex core. The group also measured a critical vortex velocity above which reversal occurs. Both these observations provide the first experimental support for the postulated reversal mechanism.

12

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

NLE Websites -- All DOE Office Websites (Extended Search)

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print Magnetic thin-film nanostructures can exhibit a magnetic vortex state in which the magnetization vectors lie in the film plane and curl around in a closed loop. At the very center of the vortex, a small, stable core exists where the magnetization points either up or down out of the plane. Three years ago, the discovery of an easy core reversal mechanism at the ALS not only made the possibility of using such systems as magnetic memories much more realistic, it also initiated investigation of the core switching mechanism itself. Now, a Belgian-German-ALS collaboration has used high-resolution, time-resolved, magnetic x-ray microscopy to experimentally reveal the first step of the reversal process: the dynamic deformation of the vortex core. The group also measured a critical vortex velocity above which reversal occurs. Both these observations provide the first experimental support for the postulated reversal mechanism.

13

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

NLE Websites -- All DOE Office Websites (Extended Search)

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print Magnetic thin-film nanostructures can exhibit a magnetic vortex state in which the magnetization vectors lie in the film plane and curl around in a closed loop. At the very center of the vortex, a small, stable core exists where the magnetization points either up or down out of the plane. Three years ago, the discovery of an easy core reversal mechanism at the ALS not only made the possibility of using such systems as magnetic memories much more realistic, it also initiated investigation of the core switching mechanism itself. Now, a Belgian-German-ALS collaboration has used high-resolution, time-resolved, magnetic x-ray microscopy to experimentally reveal the first step of the reversal process: the dynamic deformation of the vortex core. The group also measured a critical vortex velocity above which reversal occurs. Both these observations provide the first experimental support for the postulated reversal mechanism.

14

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

NLE Websites -- All DOE Office Websites (Extended Search)

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print Wednesday, 25 November 2009 00:00 Magnetic...

15

Magnetization reversal via single and double vortex states in submicron Permalloy ellipses P. Vavassori,1  

E-Print Network (OSTI)

Magnetization reversal via single and double vortex states in submicron Permalloy ellipses P University, Ithaca, New York, USA Received December 5, 2003; published 3 June 2004 The magnetization reversal of the magnetic field and to occur via the formation of one or two vortices; the one vortex state is nucleated

Metlushko, Vitali

16

Role of the core energy in the vortex Nernst effect  

Science Journals Connector (OSTI)

We present an analytical study of diamagnetism and transport in a film with superconducting phase fluctuations, formulated in terms of vortex dynamics within the Debye-Hückel approximation. We find that the diamagnetic and Nernst signals decay strongly with temperature in a manner that is dictated by the vortex core energy. Using the theory to interpret Nernst measurements of underdoped La2?xSrxCuO4 above the critical temperature regime, we obtain a considerably better fit to the data than a fit based on Gaussian order-parameter fluctuations. Our results indicate that the core energy in this system scales roughly with the critical temperature and is significantly smaller than expected from BCS theory. Furthermore, it is necessary to assume that the vortex mobility is much larger than the Bardeen-Stephen value in order to reconcile conductivity measurements with the same vortex picture. Therefore, either the Nernst signal is not due to fluctuating vortices, or vortices in underdoped La2?xSrxCuO4 have highly unconventional properties.

Gideon Wachtel and Dror Orgad

2014-11-11T23:59:59.000Z

17

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

E-Print Network (OSTI)

structure of magnetic vortex cores. Science 298, 577–580 (D. A. et al. Magnetic domain-wall logic. Science 309, 1688 (L. Magnetic domain-wall racetrack memory. Science 320, 190–

Yu, Young-Sang

2014-01-01T23:59:59.000Z

18

Polarization-selective vortex-core switching by tailored orthogonal Gaussian-pulse currents  

SciTech Connect

We experimentally demonstrate low-power-consumption vortex-core switching in magnetic nanodisks using tailored rotating magnetic fields produced with orthogonal and unipolar Gaussian-pulse currents. The optimal width of the orthogonal pulses and their time delay are found, from analytical and micromagnetic numerical calculations, to be determined only by the angular eigenfrequency {omega}{sub D} for a given vortex-state disk of polarization p, such that {sigma}=1/{omega}{sub D} and ?{Delta}t={pi}/2 p/{omega}{sub D} . The estimated optimal pulse parameters are in good agreement with the experimental results. This work lays a foundation for energy-efficient information recording in vortex-core cross-point architecture.

Jung, H.; Choi, Y. -S.; Yoo, M. -W.; Im, M. -Y.; Kim, S. -K.

2010-10-13T23:59:59.000Z

19

Numerical Simulation of the Meso-? Scale Structure and Evolution of the 1977 Johnstown Flood. Part II: Inertially Stable Warm-Core Vortex and the Mesoscale Convective Complex  

Science Journals Connector (OSTI)

A mesoscale warm-core vortex associated with the mesoscale convective complex (MCC) that produced the 1977 Johnstown flood is examined using a three-dimensional nested-grid model simulation of the flood episode. In the simulation, the vortex ...

Da-Lin Zhang; J. Michael Fritsch

1987-09-01T23:59:59.000Z

20

Memory-bit selection and recording by rotating fields in vortex-core cross-point architecture  

SciTech Connect

In one of our earlier studies [Appl. Phys. Lett. 92, 022509 (2008)], we proposed a concept of robust information storage, recording and readout, which can be implementaed in nonvolatile magnetic random-access memories and is based on the energetically degenerated twofold ground states of vortex-core magnetizations. In the present study, we experimentally demonstrate reliable memory-bit selection and information recording in vortex-core cross-point architecture, specifically using a two-by-two vortex-state disk array. In order to efficiently switch a vortex core positioned at the intersection of crossed electrodes, two orthogonal addressing electrodes are selected, and then two Gaussian pulse currents of optimal pulse width and time delay are applied. Such tailored pulse-type rotating magnetic fields which occurs only at the selected intersection is prerequisite for a reliable memory-bit selection and low-power-consumption recording of information in the existing cross-point architecture.

Yu, Y. -S.; Jung, H.; Lee, K. -S.; Fischer, P.; Kim, S. -K.

2010-10-21T23:59:59.000Z

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Optical excitation of quasiparticle pairs in the vortex core of high- T sub c superconductors  

SciTech Connect

A far-infrared resonance has been observed in superconducting YBa{sub 2}Cu{sub 3}O{sub 7} thin films in the presence of high magnetic fields. It corresponds to the quasiparticle pair creation process inside the vortex core. The resonance frequency is {omega}{sub 0}=1.3{ital kT}{sub {ital c}}/{h bar} with a linewidth 1/{tau}{congruent}0.6{omega}. This value for {omega}{sub 0} implies, within BCS theory, a large energy gap in YBa{sub 2}Cu{sub 3}O{sub 7}.

Karraie, K.; Choi, E.J.; Dunmore, F.; Liu, S.H.; Drew, H.D. (Center for Superconductivity Research, Department of Physics, University of Maryland, College Park, Maryland 20742 (United States) Laboratory for Physical Sciences, College Park, Maryland 20740 (United States)); Li, Q.; Fenner, D.B. (Advanced Fuel Research, E. Hartford, Connecticut 06138 (United States)); Zhu, Y.D.; Zhang, F. (Department of Physics, University of Cincinnati, Cincinnati, Ohio 45221 (United States))

1992-07-06T23:59:59.000Z

22

Tunable negligible-loss energy transfer between dipolar-coupled magnetic disks by stimulated vortex gyration  

E-Print Network (OSTI)

structure of magnetic vortex cores. Science 298, 577– Park,Magnetic vortex core observation in circular dots of Permalloy. Science

Jung, Hyunsung

2014-01-01T23:59:59.000Z

23

Dynamic decay of a single vortex into vortex-antivortex pairs  

SciTech Connect

A variety of metastable states, including vortices, antivortices, and their combinations, is typical for magnetically soft, thin films and patterned structures. The physics of individual spin vortices in patterned structures has been rather extensively explored. In contrast, there are few studies of the vortex–antivortex–vortex (v-av-v) system, in part because the configuration is rather challenging to obtain experimentally. We demonstrate herein how a recently proposed resonant-spin-ordering technique can be used to induce the dynamic decay of a single vortex into v-av states in elongated elements. The approach is based on first driving the system from the linear regime of constant vortex gyrations to the non-linear regime of vortex-core reversals at a fixed excitation frequency, and then subsequently reducing the excitation field back to the linear regime. This procedure stabilizes the system into a v-av-v state that is completely decoupled from the initialization excitation frequency. The newly acquired state is stable in remanence. The dynamic response of this system is expected to demonstrate a number of collective modes, depending on the combination of the vortex core polarities, and/or the excitation field direction, and, hence, is of interest for future studies.

Lendínez, Sergi [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Universidad Barcelona, Departamento Fisica Fonamental, E-08028 Barcelona (Spain); Jain, Shikha; Novosad, Valentyn, E-mail: novosad@anl.gov; Fradin, Frank Y.; Pearson, John E. [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Tejada, Javier [Universidad Barcelona, Departamento Fisica Fonamental, E-08028 Barcelona (Spain); Bader, Samuel D. [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

2014-05-07T23:59:59.000Z

24

Symmetry breaking in the formation of magnetic vortex states in a permalloy nanodisk  

E-Print Network (OSTI)

structure of magnetic vortex cores. Science 298, 6. Fischer,Magnetic Material Center, National Institute for Materials Science (Magnetic vortex core observation in circular dots of Permalloy. Science

Im, Mi-Young

2014-01-01T23:59:59.000Z

25

Z2 index for gapless fermionic modes in the vortex core of three-dimensional paired Dirac fermions  

Science Journals Connector (OSTI)

We consider the gapless modes along the vortex line of the fully gapped, momentum independent paired states of three-dimensional Dirac fermions. For this, we require the solution of fermion zero modes of the corresponding two-dimensional problem in the presence of a point vortex, in the plane perpendicular to the vortex line. Based on the spectral symmetry requirement for the existence of the zero mode, we identify the appropriate generalized Jackiw-Rossi Hamiltonians for different paired states. A four-dimensional generalized Jackiw-Rossi Hamiltonian possesses spectral symmetry with respect to an antiunitary operator, and gives rise to a single zero mode only for the odd vorticity, which is formally described by a Z2 index. In the presence of generic perturbations such as chemical potential, Dirac mass, and Zeeman couplings, the associated two-dimensional problem for the odd parity topological superconducting state maps onto two copies of generalized Jackiw-Rossi Hamiltonian, and consequently an odd vortex binds two Majorana fermions. In contrast, there are no zero-energy states for the topologically trivial s-wave superconductor in the presence of any chiral symmetry breaking perturbation in the particle-hole channel, such as regular Dirac mass. We show that the number of one-dimensional dispersive modes along the vortex line is also determined by the index of the associated two-dimensional problem. For an axial superfluid state in the presence of various perturbations, we discuss the consequences of the Z2 index on the anomaly equations.

Bitan Roy and Pallab Goswami

2014-04-14T23:59:59.000Z

26

Vortex motion rectification in Josephson junction arrays with a ratchet potential  

E-Print Network (OSTI)

By means of electrical transport measurements we have studied the rectified motion of vortices in ratchet potentials engineered on over-damped Josephson junction arrays. The rectified voltage as a function of the vortex density shows a maximum efficiency close a matching condition to the period of the ratchet potential indicating a collective vortex motion. Vortex current reversals where detected varying the driving force and vortex density revealing the influence of vortex-vortex interaction in the ratchet effect.

D. E. Shalom; H. Pastoriza

2004-11-19T23:59:59.000Z

27

Vortex Structure in Charged Condensate  

E-Print Network (OSTI)

We study magnetic fields in the charged condensate that we have previously argued should be present in helium-core white dwarf stars. We show that below a certain critical value the magnetic field is entirely expelled from the condensate, while for larger values it penetrates the condensate within flux-tubes that are similar to Abrikosov vortex lines; yet higher fields lead to the disruption of the condensate. We find the solution for the vortex lines in both relativistic and nonrelativistic theories that exhibit the charged condensation. We calculate the energy density of the vortex solution and the values of the critical magnetic fields. The minimum magnetic field required for vortices to penetrate the helium white dwarf cores ranges from roughly 10^7 to 10^9 Gauss. Fields of this strength have been observed in white dwarfs. We also calculate the London magnetic field due to the rotation of a dwarf star and show that its value is rather small.

Gabadadze, Gregory

2009-01-01T23:59:59.000Z

28

Vortex Structure in Charged Condensate  

E-Print Network (OSTI)

We study magnetic fields in the charged condensate that we have previously argued should be present in helium-core white dwarf stars. We show that below a certain critical value the magnetic field is entirely expelled from the condensate, while for larger values it penetrates the condensate within flux-tubes that are similar to Abrikosov vortex lines; yet higher fields lead to the disruption of the condensate. We find the solution for the vortex lines in both relativistic and nonrelativistic theories that exhibit the charged condensation. We calculate the energy density of the vortex solution and the values of the critical magnetic fields. The minimum magnetic field required for vortices to penetrate the helium white dwarf cores ranges from roughly 10^7 to 10^9 Gauss. Fields of this strength have been observed in white dwarfs. We also calculate the London magnetic field due to the rotation of a dwarf star and show that its value is rather small.

Gregory Gabadadze; Rachel A. Rosen

2009-05-14T23:59:59.000Z

29

Development of vortex state in circular magnetic nanodots: Theory and experiment RID A-9247-2009  

E-Print Network (OSTI)

magnetic vortex. The vortex-core diameter is controlled by competing magnetic energy contributions. For 20-nm-thick Fe dots, the values of the critical diameter (58-60 nm) and the vortex core (16-19 nm) are in very good agreement between the different...

Mejia-Lopez, J.; Altbir, D.; Landeros, P.; Escrig, J.; Romero, A. H.; Roshchin, Igor V.; Li, C-P; Fitzsimmons, M. R.; Batlle, X.; Schuller, Ivan K.

2010-01-01T23:59:59.000Z

30

Vortex configurations of bosons in an optical lattice  

SciTech Connect

The single-vortex problem in a strongly correlated bosonic system is investigated self-consistently within the mean-field theory of the Bose-Hubbard model. Near the superfluid-Mott-insulator transition, the vortex core has a tendency toward the Mott-insulating phase, with the core particle density approaching the nearest commensurate value. If the nearest-neighbor repulsion exists, the charge-density wave order may develop locally in the core. The evolution of the vortex configuration from the strong- to weak-coupling regions is studied. This phenomenon can be observed in systems of rotating ultracold atoms in optical lattices and Josephson-junction arrays.

Wu Congjun; Zhang Shoucheng [Department of Physics, McCullough Building, Stanford University, Stanford, California 94305-4045 (United States); Chen Handong [Department of Applied Physics, McCullough Building, Stanford University, Stanford, California 94305-4045 (United States); Hu Jiangpiang [Department of Physics and Astronomy, University of California, Los Angeles, California 90095-1547 (United States)

2004-04-01T23:59:59.000Z

31

Temperature dependence of vortex charges in high-temperature superconductors  

Science Journals Connector (OSTI)

Using a model Hamiltonian with d-wave superconductivity and competing antiferromagnetic (AF) interactions, the temperature (T) dependence of the vortex charge in high-Tc superconductors is investigated by numerically solving the Bogoliubov–de Gennes equations. The strength of the induced AF order inside the vortex core is T dependent. The vortex charge could be negative when the AF order with sufficient strength is present at low temperatures. At higher temperatures, the AF order may be completely suppressed and the vortex charge becomes positive. A first-order-like transition in the T-dependent vortex charge is seen near the critical temperature TAF. For an underdoped sample, the spatial profiles of the induced spin-density wave and the charge-density wave orders could have stripelike structures at TTs. As a result, a vortex charge discontinuity occurs at Ts.

Yan Chen; Z. D. Wang; C. S. Ting

2003-06-03T23:59:59.000Z

32

Reversal modes in magnetic nanotubes  

E-Print Network (OSTI)

The magnetic switching of ferromagnetic nanotubes is investigated as a function of their geometry. Two independent methods are used: Numerical simulations and analytical calculations. It is found that for long tubes the reversal of magnetization is achieved by two mechanism: The propagation of a transverse or a vortex domain wall depending on the internal and external radii of the tube.

P. Landeros; S. Allende; J. Escrig; E. Salcedo; D. Altbir; E. E. Vogel

2006-11-08T23:59:59.000Z

33

Improved vortex reactor system  

DOE Patents (OSTI)

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.

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

1995-01-01T23:59:59.000Z

34

Field dependence of the vortex structure in d-wave and s-wave superconductors  

Science Journals Connector (OSTI)

We study the vortex structure and its field dependence within the framework of the quasiclassical Eilenberger theory to find the difference between the dx2-y2- and s-wave pairings. We clarify the effect of the dx2-y2-wave nature and the vortex lattice effect on the vortex structure of the pair potential, the internal field and the local density of states. The dx2-y2-wave pairing introduces a fourfold-symmetric structure around each vortex core. With increasing field, their contribution becomes significant to the whole structure of the vortex lattice state, depending on the vortex lattice’s configuration. It is reflected in the form factor of the internal field, which may be detected by small-angle neutron scattering, or the resonance line shape of muon spin resonance and NMR experiments. We also study the induced s- and dxy-wave components around the vortex in dx2-y2-wave superconductors.

Masanori Ichioka; Akiko Hasegawa; Kazushige Machida

1999-04-01T23:59:59.000Z

35

Improved vortex reactor system  

DOE Patents (OSTI)

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.

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

1995-05-09T23:59:59.000Z

36

Vortex Characterization for Engineering Applications  

SciTech Connect

Realistic engineering simulation data often have features that are not optimally resolved due to practical limitations on mesh resolution. To be useful to application engineers, vortex characterization techniques must be sufficiently robust to handle realistic data with complex vortex topologies. In this paper, we present enhancements to the vortex topology identification component of an existing vortex characterization algorithm. The modified techniques are demonstrated by application to three realistic data sets that illustrate the strengths and weaknesses of our approach.

Jankun-Kelly, M; Thompson, D S; Jiang, M; Shannahan, B; Machiraju, R

2008-01-30T23:59:59.000Z

37

Reverse osmosis  

Science Journals Connector (OSTI)

Osmosis is a phenomenon which regulates many biological ... in explaining the biological functions which depend on osmosis, but also in creating conditions for reversing it known as ‘reverse osmosis’. Reverse osmosis

Sudhakar M Rao

2007-05-01T23:59:59.000Z

38

REVERSE OSMOSIS  

Science Journals Connector (OSTI)

REVERSE OSMOSIS ... Concentration of Apple Juice by Reverse Osmosis at Laboratory and Pilot-Plant Scales ... Concentration of Apple Juice by Reverse Osmosis at Laboratory and Pilot-Plant Scales ...

S. Sourirajan; J. P. Agrawal

1969-01-01T23:59:59.000Z

39

Reverse Osmosis  

Science Journals Connector (OSTI)

Osmosis is a phenomenon which regulates many biological ... in explaining the biological functions which depend on osmosis, but also in creating conditions for reversing it known as ‘reverse osmosis’. Reverse osmosis

Sudhakar M. Rao

2011-12-01T23:59:59.000Z

40

Reverse Osmosis  

Science Journals Connector (OSTI)

This chapter provides a survey of reverse osmosis science and technology. It begins with a ... concludes with an account of the principal current reverse osmosis applications.

H. K. Lonsdale

1986-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

High Core Electron Confinement Regimes in FTU Plasmas with Low- or Reversed-Magnetic Shear and High Power Density Electron-Cyclotron-Resonance Heating  

Science Journals Connector (OSTI)

Electron temperatures in excess of 8 keV have been obtained by electron-cyclotron-resonance heating on FTU plasmas at peak densities up to 8×1019 m -3. The magnetic shear in the plasma core is low or negative, and the electron heat diffusivity remains at, or below, the Ohmic level (0.2 m 2/s), in spite of the very large heating power density (10–20 MW/m 3) which produces extremely high temperature gradients (up to 120 keV/m). The ion heat transport remains at the neoclassical level.

P. Buratti et al.

1999-01-18T23:59:59.000Z

42

UBIQUITOUS SOLAR ERUPTIONS DRIVEN BY MAGNETIZED VORTEX TUBES  

SciTech Connect

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 eruption 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 the surrounding material up, generating shocks. Our simulations reveal complicated high-speed flow patterns and thermodynamic and magnetic structure in the erupting vortex tubes. The main new results are: (1) the eruptions are initiated in the subsurface layers and are driven by high-pressure gradients in the subphotosphere and photosphere and by the Lorentz force in the higher atmosphere layers; (2) the fluctuations in the vortex tubes penetrating into the chromosphere are quasi-periodic with a characteristic period of 2-5 minutes; and (3) the eruptions are highly non-uniform: the flows are predominantly downward in the vortex tube cores and upward in their surroundings; the plasma density and temperature vary significantly across the eruptions.

Kitiashvili, I. N.; Kosovichev, A. G. [Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305 (United States); Lele, S. K.; Mansour, N. N.; Wray, A. A., E-mail: irinasun@stanford.edu [Center for Turbulence Research, Stanford University, Stanford, CA 94305 (United States)

2013-06-10T23:59:59.000Z

43

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

SciTech Connect

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.

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)

2012-02-01T23:59:59.000Z

44

Vortex lines and transitions in superfluid hydrodynamics  

Science Journals Connector (OSTI)

...Preface to Vortices, dislocations, and line singularities in partial differential equations...Leslie and J. R. Ockendon. Vortex lines and transitions in superfluid hydrodynamics...nature and the motion of qunatized vortex lines. This paper illustrates the transitions...

1997-01-01T23:59:59.000Z

45

Gravity waves from vortex dipoles and jets  

E-Print Network (OSTI)

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...

Wang, Shuguang

2009-05-15T23:59:59.000Z

46

Flame–vortex interaction in a reacting vortex ring  

Science Journals Connector (OSTI)

Direct numerical simulations are used to study the flame–vortex interaction in a laminar reacting vortex ring. The chemical reaction occurs by a one-step Arrhenius-type reaction that mimics the combustion of typical hydrocarbon and air. The ring is generated by an axisymmetric jet that is impulsed to emit a cold fuel through a nozzle. The fuel enters a quiescent ambient at a much higher temperature. By adjusting the ratio of the ambient and fuel temperatures the ignition either occurs during the formation or post-formation phase of the ring. When ignition occurs during the formation phase of the ring the bulk of combustion is by a flame at the front of the vortex bubble. When ignition is delayed until after the formation phase most of the reaction occurs inside the vortex ring. It is found that premixing the fuel and the oxidizer enhances the amount of product formation. The heat released from the reaction significantly affects production redistribution and diffusion of the vorticity throughout the field. The results of the simulations also reveal that the heat of reaction affects the strain rate fields differently depending on when the ignition of the ring occurs.

J. S. Hewett; C. K. Madnia

1998-01-01T23:59:59.000Z

47

Vortex molecules in Bose-Einstein condensates  

E-Print Network (OSTI)

Stable vortex dimers are known to exist in coherently coupled two component Bose-Einstein condensates (BECs). We construct stable vortex trimers in three component BECs and find that the shape can be controlled by changing the internal coherent (Rabi) couplings. Stable vortex N-omers are also constructed in coherently coupled N-component BECs. We classify all possible N-omers in terms of the mathematical graph theory. Next, we study effects of the Rabi coupling in vortex lattices in two-component BECs. We find how the vortex lattices without the Rabi coupling known before are connected to the Abrikosov lattice of integer vortices with increasing the Rabi coupling. In this process, vortex dimers change their partners in various ways at large couplings. We then find that the Abrikosov lattices are robust in three-component BECs.

Muneto Nitta; Minoru Eto; Mattia Cipriani

2013-07-16T23:59:59.000Z

48

Reconnection of vortex filaments and Kolmogorov spectrum  

E-Print Network (OSTI)

The energy spectrum of the 3D velocity field, induced by collapsing vortex filaments is studied. One of the aims of this work is to clarify the appearance of the Kolmogorov type energy spectrum $E(k)\\varpropto k^{-5/3}$, observed in many numerical works on discrete vortex tubes (quantized vortex filaments in quantum fluids). Usually, explaining classical turbulent properties of quantum turbulence, the model of vortex bundles, is used. This model is necessary to mimic the vortex stretching, which is responsible for the energy transfer in classical turbulence. In our consideration we do not appeal to the possible "bundle arrangement" but explore alternative idea that the turbulent spectra appear from singular solution, which describe the collapsing line at moments of reconnection. One more aim is related to an important and intensively discussed topic - a role of hydrodynamic collapse in the formation of turbulent spectra. We demonstrated that the specific vortex filament configuration generated the spectrum $E...

Nemirovskii, Sergey K

2014-01-01T23:59:59.000Z

49

Quantum Kinematics of Bosonic Vortex Loops  

SciTech Connect

Poisson structure for vortex filaments (loops and arcs) in 2D ideal incompressible fluid is analyzed in detail. Canonical coordinates and momenta on coadjoint orbits of the area-preserving diffeomorphism group, associated with such vortices, are found. The quantum space of states in the simplest case of ''bosonic'' vortex loops is built within a geometric quantization approach to the description of a quantum fluid. Fock-like structure and non-local creation and annihilation operators of quantum vortex filaments are introduced.

Goldin, G.A.; Owczarek, R.; Sharp, D.H.

1999-05-06T23:59:59.000Z

50

Vortex Hydro Energy Develops Transformational Technology to Harness...  

Energy Savers (EERE)

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

51

Core sizes and dynamical instabilities of giant vortices in dilute Bose-Einstein condensates  

SciTech Connect

Motivated by a recent demonstration of cyclic addition of quantized vorticity into a Bose-Einstein condensate, the vortex pump, we study dynamical instabilities and core sizes of giant vortices. The core size is found to increase roughly as a square-root function of the quantum number of the vortex, whereas the strength of the dynamical instability either saturates to a fairly low value or increases extremely slowly for large quantum numbers. Our studies suggest that giant vortices of very high angular momenta may be achieved by gradually increasing the operation frequency of the vortex pump.

Kuopanportti, Pekko; Lundh, Emil; Huhtamaeki, Jukka A. M.; Pietilae, Ville; Moettoenen, Mikko [Department of Applied Physics/COMP, Aalto University School of Science and Technology, P.O. Box 15100, FI-00076 AALTO (Finland); Department of Physics, Umeaa University, SE-90187 Umeaa (Sweden); Department of Applied Physics/COMP, Aalto University School of Science and Technology, P.O. Box 15100, FI-00076 AALTO, Finland and Department of Physics, Okayama University, Okayama 700-8530 (Japan); Department of Applied Physics/COMP, Aalto University School of Science and Technology, P.O. Box 15100, FI-00076 AALTO, Finland and Australian Research Council Centre of Excellence for Quantum Computer Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney NSW 2052 (Australia); Department of Applied Physics/COMP, Aalto University School of Science and Technology, P.O. Box 15100, FI-00076 AALTO, Finland, Australian Research Council Centre of Excellence for Quantum Computer Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney NSW 2052 (Australia) and Low Temperature Laboratory, Aalto University School of Science and Technology, P.O. Box 13500, FI-00076 AALTO (Finland)

2010-02-15T23:59:59.000Z

52

Characterization of The Dalles Dam Spillbay 6 Vortex Using Surface Entrained Sensor Fish Device: Preliminary Report  

SciTech Connect

This document summarizes the pilot study to characterize The Dalles Dam Spillbay 6 vortex using a surface entrained Sensor Fish device. It was conducted by Pacific Northwest National Laboratory (PNNL) on April 13 and 14, 2006. The total spill was controlled at approximately 110 kcfs, the forebay elevation was 157.89 ft, and the discharge of Bay 6 at the tested gate opening of 14 ft was approximately 18 kcfs. The objectives of the full study are to (1) develop baseline conditions for the detailed analysis of Sensor Fish measurements by deploying Sensor Fish in different surface locations in the vortex periphery; (2) observe the entrainment pattern and extract hydraulic data of interest such as acceleration, rotation, pressure, and estimated velocity of Sensor Fish or drogues; (3) integrate the experimental results with companion computational fluid dynamics (CFD) simulations and inertial particle tracking studies. A total of 12 Sensor Fish were released in the surface at upstream edge, left edge, downstream edge, and the core of the vortex at Bay 6. Because of the high discharge, the vortex patterns at the test condition were less consistent than the patterns observed at lower discharges. Compared with the Sensor Fish released at mid-bay at Bay 6, Sensor Fish released from the surface at the vortex experienced higher pressure fluctuations, a larger percentage of severe events, and much more rapid angular velocities.

Deng, Zhiqun; Richmond, Marshall C.; Carlson, Thomas J.

2006-06-22T23:59:59.000Z

53

The idea of vortex energy  

E-Print Network (OSTI)

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.

V. E. Shapiro

2011-09-22T23:59:59.000Z

54

Stability of vortex solitons in a photorefractive optical lattice  

E-Print Network (OSTI)

://www.njp.org/ DOI: 10.1088/1367-2630/6/1/047 Abstract. Stability of on- and off-site vortex solitons with unit stable than off-site ones. Increasing the DC field stabilizes both types of vortex solitons. Contents 1. Introduction 2 2. Off-site vortex solitons 4 3. On-site vortex solitons 9 4. Summary 11 Acknowledgments 11

Yang, Jianke

55

Core Specialization  

NLE Websites -- All DOE Office Websites (Extended Search)

Core Specialization Core Specialization Core Specialization Core Specialization (CS) is a feature of the Cray operating system that allows the user to reserve one or more cores per node for handling system services, and thus reduce the effects of timing jitter due to interruptions from the operating system at the expense of (possibly) requiring more nodes to run an application. The specialized cores may also be used in conjunction with Cray's MPI asynchronous progress engine [1] to improve the overlap of communication and computation for applications that use non-blocking MPI functions. In the absence of CS, the compute cores must service their own non-blocking calls. Hyper-Threading complicates questions abouty the most effective use of processor resources. HT doubles the number of compute stream (i.e.

56

Core Specialization  

NLE Websites -- All DOE Office Websites (Extended Search)

Core Core Specialization Core Specialization Core Specialization (CS) is a feature of the Cray operating system that allows the user to reserve one or more cores per node for handling system services, and thus reduce the effects of timing jitter due to interruptions from the operating system at the expense of (possibly) requiring more nodes to run an application. The specialized cores may also be used in conjunction with Cray's MPI asynchronous progress engine [1] to improve the overlap of communication and computation for applications that use non-blocking MPI functions. In the absence of CS, the compute cores must service their own non-blocking calls. Hyper-Threading complicates questions abouty the most effective use of processor resources. HT doubles the number of compute stream (i.e.

57

Lower pseudogap phase of Mott insulators: A spin/vortex liquid state  

Science Journals Connector (OSTI)

The pseudogap phase is considered to be a new state of matter in the phase string model of the doped Mott insulator, which is composed of two distinct regimes known as the upper and lower pseudogap phases, respectively. The former corresponds to the formation of spin-singlet pairing, the magnetic characterizations of which have been recently studied [Phys. Rev. B 72, 104520 (2005)]. The latter, as a low-temperature regime of the pseudogap phase, is systematically explored in this work, which is characterized by the formation of the Cooper pair amplitude and described by a generalized Ginzburg-Landau theory. Elementary excitation in this phase is a charge-neutral object carrying spin-1?2 and locking with a supercurrent vortex, known as a spinon-vortex composite. Such a lower pseudogap phase can be regarded as a vortex liquid state due to the presence of free spinon vortices. Here thermally excited spinon vortices destroy the phase coherence and are responsible for the nontrivial Nernst effect and diamagnetism. The transport entropy and core energy associated with a spinon vortex are determined by the spin degrees of freedom. Such a spontaneous vortex liquid phase can be also considered as a spin liquid with a finite correlation length and gaped S=1?2 excitations, where a resonancelike nonpropagating spin mode emerges at the antiferromagnetic wavevector (?,?) with a doping-dependent characteristic energy. The superconducting phase is closely related to the lower pseudogap phase by a topological transition with spinon vortices and antivortices forming bound pairs and the emergence of fermionic quasiparticles as holon-spinon-vortex bound objects. A quantitative phase diagram in the parameter space of doping, temperature, and magnetic field is determined. Comparisons with experiments are also made.

Zheng-Yu Weng and Xiao-Liang Qi

2006-10-26T23:59:59.000Z

58

Particle resuspension by an impacting vortex ring  

Science Journals Connector (OSTI)

Coherent vortex structures play a significant and important role in the dynamics of many commonly occurring natural flows, for example turbulent boundary layers and channel flows. One particularly important fe...

Rick J. Munro; Stuart B. Dalziel

2003-01-01T23:59:59.000Z

59

‘Optimal’ vortex rings and aquatic propulsion mechanisms  

Science Journals Connector (OSTI)

...vortex rings and aquatic propulsion mechanisms P. F. Linden...fluid mechanics behind these propulsion mechanisms and show that...over the cycle. 4. FISH PROPULSION BY UNDULATORY SWIMMING Most marine organisms have only discrete...

2004-01-01T23:59:59.000Z

60

Polarization dependent forces in optical vortex pipeline  

Science Journals Connector (OSTI)

We study both, theoretically and in experiments, the dependence of optical forces acting on a spherical particle guided in air with an optical vortex beam, on the light polarization...

Eckerskorn, Niko; Krolikowski, Wieslaw; Shvedov, Vladlen; Rode, Andrei

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Airfoil Vortex Induced Vibration suppression devices  

E-Print Network (OSTI)

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 ...

Lee, Evan J. (Evan Joseph)

2007-01-01T23:59:59.000Z

62

Holographic Vortex Liquids and Superfluid Turbulence  

Science Journals Connector (OSTI)

...of Kelvin waves flowing along vortex strings in 3D quantum turbulence...theory correlators from non-critical string theory . Phys. Lett. B...S. , Emergence of turbulence in an oscillating Bose-Einstein condensate . Phys. Rev...

Paul M. Chesler; Hong Liu; Allan Adams

2013-07-26T23:59:59.000Z

63

Direct Imaging of Antiferromagnetic Vortex States  

NLE Websites -- All DOE Office Websites (Extended Search)

Direct Imaging of Antiferromagnetic Vortex States Print Direct Imaging of Antiferromagnetic Vortex States Print Magnetic materials are characterized by the ordering of electron spins, with nearest-neighbor spins parallel to each other in ferromagnetic (FM) materials and antiparallel to each other in antiferromagnetic (AFM) materials. As the size of a magnetic system is reduced to micron scale, it has been shown that the spins in an FM microstructure can curl around to form a magnetic vortex state. While there has been intensive activity in the study of vortex states in FM disks, there has been no direct observation of such states in an AFM microstructure, although theory predicts many interesting and unique properties for the AFM vortex state. Recently, a research team from Berkeley, Korea, and China has taken the first direct image of an AFM vortex in multilayered magnetic disk structures using x-ray magnetic linear dichroism (XMLD) and photoemission electron microscopy (PEEM) at ALS Beamlines 4.0.2 and 11.0.1 , respectively. The experiments observed two types of AFM vortices, one of which has no analogue in FM vortices.

64

Direct Imaging of Antiferromagnetic Vortex States  

NLE Websites -- All DOE Office Websites (Extended Search)

Direct Imaging of Antiferromagnetic Vortex States Print Direct Imaging of Antiferromagnetic Vortex States Print Magnetic materials are characterized by the ordering of electron spins, with nearest-neighbor spins parallel to each other in ferromagnetic (FM) materials and antiparallel to each other in antiferromagnetic (AFM) materials. As the size of a magnetic system is reduced to micron scale, it has been shown that the spins in an FM microstructure can curl around to form a magnetic vortex state. While there has been intensive activity in the study of vortex states in FM disks, there has been no direct observation of such states in an AFM microstructure, although theory predicts many interesting and unique properties for the AFM vortex state. Recently, a research team from Berkeley, Korea, and China has taken the first direct image of an AFM vortex in multilayered magnetic disk structures using x-ray magnetic linear dichroism (XMLD) and photoemission electron microscopy (PEEM) at ALS Beamlines 4.0.2 and 11.0.1 , respectively. The experiments observed two types of AFM vortices, one of which has no analogue in FM vortices.

65

Direct Imaging of Antiferromagnetic Vortex States  

NLE Websites -- All DOE Office Websites (Extended Search)

Direct Imaging of Antiferromagnetic Vortex States Print Direct Imaging of Antiferromagnetic Vortex States Print Magnetic materials are characterized by the ordering of electron spins, with nearest-neighbor spins parallel to each other in ferromagnetic (FM) materials and antiparallel to each other in antiferromagnetic (AFM) materials. As the size of a magnetic system is reduced to micron scale, it has been shown that the spins in an FM microstructure can curl around to form a magnetic vortex state. While there has been intensive activity in the study of vortex states in FM disks, there has been no direct observation of such states in an AFM microstructure, although theory predicts many interesting and unique properties for the AFM vortex state. Recently, a research team from Berkeley, Korea, and China has taken the first direct image of an AFM vortex in multilayered magnetic disk structures using x-ray magnetic linear dichroism (XMLD) and photoemission electron microscopy (PEEM) at ALS Beamlines 4.0.2 and 11.0.1 , respectively. The experiments observed two types of AFM vortices, one of which has no analogue in FM vortices.

66

Reconnection of vortex filaments and Kolmogorov spectrum  

E-Print Network (OSTI)

The energy spectrum of the 3D velocity field, induced by collapsing vortex filaments is studied. One of the aims of this work is to clarify the appearance of the Kolmogorov type energy spectrum $E(k)\\varpropto k^{-5/3}$, observed in many numerical works on discrete vortex tubes (quantized vortex filaments in quantum fluids). Usually, explaining classical turbulent properties of quantum turbulence, the model of vortex bundles, is used. This model is necessary to mimic the vortex stretching, which is responsible for the energy transfer in classical turbulence. In our consideration we do not appeal to the possible "bundle arrangement" but explore alternative idea that the turbulent spectra appear from singular solution, which describe the collapsing line at moments of reconnection. One more aim is related to an important and intensively discussed topic - a role of hydrodynamic collapse in the formation of turbulent spectra. We demonstrated that the specific vortex filament configuration generated the spectrum $E(k)$ close to the Kolmogorov dependence and discussed the reason for this as well as the reason for deviation. We also discuss the obtained results from point of view of the both classical and quantum turbulence.

Sergey K. Nemirovskii

2014-04-19T23:59:59.000Z

67

Reverse Osmosis and Ultrafiltration  

Science Journals Connector (OSTI)

Economic comparisons indicate reverse osmosis to be more cost effective than distillation ... membranes, leading to a wider scope of reverse osmosis applications, including the purification of used water ... tran...

Prof. Dr. Anthony Delyannis; Dr. Euridike-Emmy Delyannis

1980-01-01T23:59:59.000Z

68

Vortex Hydro Energy LLC | Open Energy Information  

Open Energy Info (EERE)

Hydro Energy LLC Hydro Energy LLC Jump to: navigation, search Name Vortex Hydro Energy LLC Address 4870 West Clark Rd Suite 108 Place Ypsilanti Zip 48197 Sector Marine and Hydrokinetic Phone number 734.971.4020 Website http://www.vortexhydroenergy.c Region United States LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This company is listed in the Marine and Hydrokinetic Technology Database. This company is involved in the following MHK Projects: Marine Hydrodynamics Laboratory at the University of Michigan This company is involved in the following MHK Technologies: Vortex Induced Vibrations Aquatic Clean Energy VIVACE This article is a stub. You can help OpenEI by expanding it. Retrieved from "http://en.openei.org/w/index.php?title=Vortex_Hydro_Energy_LLC&oldid=678497

69

Sediment resuspension and erosion by vortex rings  

Science Journals Connector (OSTI)

Particle resuspension and erosion induced by a vortex ringinteracting with a sediment layer was investigated experimentally using flow visualization (particle image velocimetry) high-speed video and a recently developed light attenuation method for measuring displacements in bed level. Near-spherical sediment particles were used throughout with relative densities of 1.2–7 and diameters ( d ) ranging between 90 and 1600 ? ? m . Attention was focused on initially smooth horizontal bedforms with the vortex ring aligned to approach the bed vertically. Interaction characteristics were investigated in terms of the dimensionless Shields parameter defined using the vortex-ring propagation speed. The critical conditions for resuspension (whereby particles are only just resuspended) were determined as a function of particle Reynolds number (based on the particle settling velocity and d ). The effects of viscous damping were found to be significant for d / ? resuspension volumes are analyzed as a function interaction time impact condition and sediment size.

R. J. Munro; N. Bethke; S. B. Dalziel

2009-01-01T23:59:59.000Z

70

Reversible logic for supercomputing  

Science Journals Connector (OSTI)

This paper is about making reversible logic a reality for supercomputing. Reversible logic offers a way to exceed certain basic limits on the performance of computers, yet a powerful case will have to be made to justify its substantial development expense. ... Keywords: applications modeling, climate change global warming, computer architecture, quantum dot cellular automata, reversible logic, supercomputing

Erik P. DeBenedictis

2005-05-01T23:59:59.000Z

71

Vortex reconnections between coreless vortices in binary condensates  

SciTech Connect

Vortex reconnections plays an important role in the turbulent flows associated with the superfluids. To understand the dynamics, we examine the reconnections of vortex rings in the superfluids of dilute atomic gases confined in trapping potentials using Gross-Petaevskii equation. Further more we study the reconnection dynamics of coreless vortex rings, where one of the species can act as a tracer.

Gautam, S. [Indian Institute of Science, Bangalore-560 012 (India); Suthar, K.; Angom, D. [Physical Research Laboratory, Ahmedabad-380 009 (India)

2014-02-11T23:59:59.000Z

72

PHYSICS OF FLUIDS 24, 125108 (2012) Quantum vortex reconnections  

E-Print Network (OSTI)

is continuous, not discrete, and parts of the initial vortical tubes can be left behind as vortex threads, whichPHYSICS OF FLUIDS 24, 125108 (2012) Quantum vortex reconnections S. Zuccher,1 M. Caliari,1 A. W that the minimum distance between vortices scales differently with time before and after the vortex reconnection

Zuccher, Simone

73

Flow Relationships in Reverse Osmosis  

Science Journals Connector (OSTI)

Flow Relationships in Reverse Osmosis ... Effects of Hydrolysis on Cellulose Acetate Reverse-Osmosis Transport Coefficients ... Effects of Hydrolysis on Cellulose Acetate Reverse-Osmosis Transport Coefficients ...

Ulrich Merten

1963-08-01T23:59:59.000Z

74

Correlated vortex pinning in slightly orthorhombic twinned Ba(Fe1-xCox)2As2 single crystals: Possible shift of the vortex-glass/liquid transition  

SciTech Connect

The interest in twin-boundary (TB) planes as a source of vortex pinning has been recently renewed with the discovery of the new iron-arsenide pnictide superconductors. In the family of compounds Ba(Fe1-xCox)2As2 a structural transition from a tetragonal to orthorhombic lattice takes place for compounds with xvortex cores. In this work we investigate the changes in anisotropy produced by subtle differences in the Co doping level, in the neighborhood of the structural transition, in good-quality single crystals. Using a scaling approach we are able to determine the angular regions where correlated or uncorrelated disorder prevails. In the tetragonal samples (x>xcr) there is no twinning and we find good agreement with the expected scaling function under uncorrelated disorder, with small anisotropy values similar to those reported in the literature. We show that in the orthorhombic samples (xvortex liquid-glass transition temperature.

Bermudez, M. Marziali [Universidad de Buenos Aires; Pasquini, G. [Universidad de Buenos Aires; Budko, Sergey L. [Ames Laboratory; Canfield, Paul C. [Ames Laboratory

2013-02-28T23:59:59.000Z

75

Neutron Scattering Studies of Vortex Matter in Type-II Superconductors  

SciTech Connect

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.

Xinsheng Ling

2012-02-02T23:59:59.000Z

76

Tokamak Equilibria with Reversed Current Density  

Science Journals Connector (OSTI)

Observations of nearly zero toroidal current in the central region of tokamaks (the “current hole”) raises the question of the existence of toroidal equilibria with very low or reversed current in the core. The solutions of the Grad-Shafranov equilibrium equation with hollow toroidal current density profile including negative current density in the plasma center are investigated. Solutions of the corresponding eigenvalue problem provide simple examples of such equilibrium configurations. More realistic equilibria with toroidal current density reversal are computed using a new equilibrium problem formulation and computational algorithm which do not assume nested magnetic surfaces.

A. A. Martynov; S. Yu. Medvedev; L. Villard

2003-08-21T23:59:59.000Z

77

Jammed vortex matter Hajime Yoshino1  

E-Print Network (OSTI)

. Abstract: Irrationally frustrated Josephson junction array (JJA), namely JJA with irrational number density point. Figure 1: Josephson junction array (JJA) on a square lattice. The vertexes and bonds represent- not develop usual periodic vortex lattices. 1 Introduction Josephson junction array under mag- netic field

Katsumoto, Shingo

78

Vortex lines in films: Fields and interactions  

Science Journals Connector (OSTI)

General expressions are given for the magnetic field and energy of arbitrary arrangements of straight and curved vortices in an anisotropic superconductor film of finite thickness within anisotropic London theory. As examples we consider the magnetic field and interaction of straight perpendicular vortex lines in films of finite thickness.

Gilson Carneiro and Ernst Helmut Brandt

2000-03-01T23:59:59.000Z

79

Vortex Jitter in Hover Swathi M. Mula  

E-Print Network (OSTI)

78712, USA Abstract The trajectory of the tip vortex of a reduced-scale, 1 m diameter, four-bladed rotor condition of the rotor is at a blade loading of CT / = 0.0645 and a rotational speed of 1240RPM wake dominated by the tip vortices shed from the rotor blades. The complexity of the flow

Tinney, Charles E.

80

The multiple vortex nature of tropical cyclogenesis  

E-Print Network (OSTI)

) __________________________ __________________________ John Nielsen-Gammon Craig Epifanio (Chair of Committee) (Member) __________________________ __________________________ Fuqing Zhang Hongxing Liu (Member) (Member) December 2004 Major Subject: Atmospheric Sciences... iii ABSTRACT The Multiple Vortex Nature of Tropical Cyclogenesis. (December 2004) Jason Allen Sippel, B.S., Texas A&M University Chair of Advisory Committee: Dr. John Nielsen-Gammon This thesis contains an observational analysis...

Sippel, Jason Allen

2005-02-17T23:59:59.000Z

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Quenching Processes in Flame-Vortex Interactions  

E-Print Network (OSTI)

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

Zingale, Michael

82

Vortex dynamics in 4 Banavara N. Shashikanth  

E-Print Network (OSTI)

during the interaction of a pair of counter-rotating vortices Phys. Fluids 24, 014107 (2012) The onset of oblique vortex shedding behind a heated circular cylinder in laminar wake regime Phys. Fluids 24, 011701 fluids Phys. Fluids 23, 115106 (2011) Asymptotic properties of wall-induced chaotic mixing in point

Shashikanth, Banavara N.

83

Reversible Acid Gas Capture  

SciTech Connect

Pacific Northwest National Laboratory scientist David Heldebrant demonstrates how a new process called reversible acid gas capture works to pull carbon dioxide out of power plant emissions.

Dave Heldebrant

2009-08-01T23:59:59.000Z

84

Reversible Acid Gas Capture  

ScienceCinema (OSTI)

Pacific Northwest National Laboratory scientist David Heldebrant demonstrates how a new process called reversible acid gas capture works to pull carbon dioxide out of power plant emissions.

Dave Heldebrant

2012-12-31T23:59:59.000Z

85

Synthesis and magnetic reversal of bi-conical Ni nanostructures  

SciTech Connect

Template synthesis in polyethylene terephthalate (PET) membranes has been used to grow hour glass shaped nickel nanowires with a constriction in the range of tens of nanometers at the center. Anisotropic magnetoresistance measurements have been performed on a single nanowire to follow magnetization reversal of the structure. The results are explained via 3D micromagnetic simulations showing the appearance of a complex vortex state close to the constriction whose propagation depends on the angle between the cone axis and the applied field. The interest of this original growth process for spintronics is discussed.

Biziere, N. [Laboratoire des Solides Irradies, CEA/CNRS/Ecole Polytechnique, Ecole Polytechnique, 91128 Palaiseau Cedex (France); CEMES-CNRS, 29 Rue Jeanne Marvig, 31055 Toulouse (France); Lassalle Ballier, R.; Viret, M. [Service de Physique de l'Etat Condense, DSM/IRAMIS/SPEC, CEA Saclay URA CNRS 2464, 91191 Gif-Sur-Yvette Cedex (France); Clochard, M. C.; Wade, T. L.; Wegrowe, J. E. [Laboratoire des Solides Irradies, CEA/CNRS/Ecole Polytechnique, Ecole Polytechnique, 91128 Palaiseau Cedex (France); Balanzat, E. [CIMAP, Unite Mixte CEA-CNRS-ENSICAEN, F-14070 Caen Cedex 5 (France)

2011-09-15T23:59:59.000Z

86

Nanoscale strain-induced pair suppression as a vortex-pinning mechanism in high- temperature superconductors  

SciTech Connect

Boosting large-scale superconductor applications require nanostructured conductors with artificial pinning centres immobilizing quantized vortices at high temperature and magnetic fields. Here we demonstrate a highly effective mechanism of artificial pinning centers in solution-derived high-temperature superconductor nanocomposites through generation of nanostrained regions where Cooper pair formation is suppressed. The nanostrained regions identified from transmission electron microscopy devise a very high concentration of partial dislocations associated with intergrowths generated between the randomly oriented nanodots and the epitaxial YBa{sub 2}Cu{sub 3}O{sub 7} matrix. Consequently, an outstanding vortex-pinning enhancement correlated to the nanostrain is demonstrated for four types of randomly oriented nanodot, and a unique evolution towards an isotropic vortex-pinning behaviour, even in the effective anisotropy, is achieved as the nanostrain turns isotropic. We suggest a new vortex-pinning mechanism based on the bond-contraction pairing model, where pair formation is quenched under tensile strain, forming new and effective core-pinning regions.

Llordes, Anna [ICMAB, Barcelona, Spain; Palau, A. [ICMAB, Barcelona, Spain; Gazquez, J. [Oak Ridge National Laboratory (ORNL); Coll, M. [ICMAB, Barcelona, Spain; Vlad, R. [ICMAB, Barcelona, Spain; Pomar, A. [ICMAB, Barcelona, Spain; Arbiol, Jordi [ICMAB, Barcelona, Spain; Guzman, Roger [ICMAB, Barcelona, Spain; Ye, S. [ICMAB, Barcelona, Spain; Rouco, V [ICMAB, Barcelona, Spain; Sandiumenge, Felip [ICMAB, Barcelona, Spain; Ricart, Susagna [ICMAB, Barcelona, Spain; Puig, Teresa [ICMAB, Barcelona, Spain; Varela del Arco, Maria [ORNL; Chataigner, D. [CRISMAT, Caen, France; Vanacken, J. [INPAC-Institute for Nanoscale Physics and Chemistry, Leuven, Belgium; Gutierrez, J. [INPAC-Institute for Nanoscale Physics and Chemistry, Leuven, Belgium; Moschalkov, V. [INPAC-Institute for Nanoscale Physics and Chemistry, Leuven, Belgium; Deutscher, G. [Tel Aviv University; Magen Dominguez, Cesar [ORNL; Obradors, Xavier [ICMAB, Barcelona, Spain

2012-01-01T23:59:59.000Z

87

A Vortex Contactor for Carbon Dioxide Separations  

NLE Websites -- All DOE Office Websites (Extended Search)

Vortex Contactor for Carbon Dioxide Separations Vortex Contactor for Carbon Dioxide Separations Kevin T. Raterman (ratekt@inel.gov; 208-526-5444) Michael McKellar (mgq@inel.gov; 208-526-1346) Anna Podgorney (poloak@inel.gov; 208-526-0064) Douglas Stacey (stacde@inel.gov; 208-526-3938) Terry Turner (tdt@inel.gov; 208-526-8623) Idaho National Engineering and Environmental Laboratory P.O. Box 1625 Idaho Falls, Idaho 83415-2110 Brian Stokes (bxs9@pge.com; 415-972-5591) John Vranicar (jjv2@pge.com; 415-972-5591) Pacific Gas & Electric Company 123 Mission Street San Francisco, CA 94105 Introduction Many analysts 1,2,3 identify carbon dioxide (CO 2 ) capture and separation as a major roadblock in efforts to cost effectively mitigate greenhouse gas emissions via sequestration. An assessment 4 conducted by the International Energy Agency (IEA)

88

Vortex Dynamics in NanoScale Materials  

NLE Websites -- All DOE Office Websites (Extended Search)

Into the Vortex: Dynamics in Nanoscale Materials Into the Vortex: Dynamics in Nanoscale Materials Micron and nanosized magnets are of great interest for their potential applications in new electronic devices, such as magnetic random access memories. As the size of magnets is reduced to a 1-micron scale and below, the boundaries (surfaces, perimeters, etc) of the objects begin to profoundly influence both the static and dynamic behavior of the materials. Researchers from Argonne's Materials Science Division (MSD), Center for Nanoscale Materials (CNM), and Advanced Photon Source (APS) have recently examined the dynamics of 3- to 7-micron-diameter NiFe alloy disks with a combination of theoretical calculations and a new time-resolved magnetic imaging technique using synchrotron-based x-ray photoemission electron

89

Acceleration and vortex filaments in turbulence  

E-Print Network (OSTI)

We report recent results from a high resolution numerical study of fluid particles transported by a fully developed turbulent flow. Single particle trajectories were followed for a time range spanning more than three decades, from less than a tenth of the Kolmogorov time-scale up to one large-eddy turnover time. We present some results concerning acceleration statistics and the statistics of trapping by vortex filaments.

F. Toschi; L. Biferale; G. Boffetta; A. Celani; B. J. Devenish; A. Lanotte

2005-01-23T23:59:59.000Z

90

Synthesis of reversible sequential elements  

Science Journals Connector (OSTI)

To construct a reversible sequential circuit, reversible sequential elements are required. This work presents novel designs of reversible sequential elements such as the D latch, JK latch, and T latch. Based on these reversible latches, we construct ... Keywords: Reversible logic, sequential circuits, sequential elements

Min-Lun Chuang; Chun-Yao Wang

2008-01-01T23:59:59.000Z

91

Jet?vortex Interaction: A Numerical Study  

Science Journals Connector (OSTI)

The interaction of a vortex and a jet plays an important role for many industrial processes such as Carbon Black formation or combustion in diesel engines. The knowledge of physics of these phenomena is crucial for engineers but also for scientists who wish to reveal many interesting and complex issues hidden there. In this research we numerically investigate cases where a cylindrical reactor is charged with gas injected through five ports. The first one is located along the main axis of the cylinder and this leads to the formation of the main jet. The other four ports are situated along the side walls such that the gas entering the cylinder tangentially through them causes a vortex to be formed. The objective of this paper is to show the fundamental physical phenomena and also how the initial and boundary conditions influence the results. Our most important observation at this stage is that the mixing process is more intense if the vortex is inclined towards x?axis. The results are mainly shown as snapshots of gas velocity.

Catalin G. Ilea; Pawel Kosinski; Alex C. Hoffmann

2009-01-01T23:59:59.000Z

92

Liquid Vortex Shielding for Fusion Energy Applications  

SciTech Connect

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.

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)

2005-05-15T23:59:59.000Z

93

Novel Vortex Generator and Mode Converter for Electron Beams  

Science Journals Connector (OSTI)

A mode converter for electron vortex beams is described. Numerical simulations, confirmed by experiment, show that the converter transforms a vortex beam with a topological charge m=±1 into beams closely resembling Hermite-Gaussian HG10 and HG01 modes. The converter can be used as a mode discriminator or filter for electron vortex beams. Combining the converter with a phase plate turns a plane wave into modes with topological charge m=±1. This combination serves as a generator of electron vortex beams of high brilliance.

P. Schattschneider; M. Stöger-Pollach; J. Verbeeck

2012-08-22T23:59:59.000Z

94

Energy Separation And Lox Separation Studies In Vortex Tubes.  

E-Print Network (OSTI)

??Vortex Tube (VT) is a simple device having no moving mechanical parts, in which compressed gas at high pressure is injected through one or more… (more)

Behera, Upendra

2011-01-01T23:59:59.000Z

95

An application of vortex cancellation to vortex generator techniques in low speed wind tunnels  

E-Print Network (OSTI)

'lugs/ft-sec Axial distance between sets of vortex generators root chord lengths /Y Vertical dimension of duct cross section Tube height/Y in. none ~St i t ()i ()2 (), ( )?q Measured at station g 1 Measured at Station 0 8 Upstream srl... TABLE I II BOUNDARY LAYER PROFILE DATA IN THE VICINITY OF A VORTEX FILAMENT AT STATION 0 7 Tube Number I 2 3 4. 5 6 7 8 9 '10 I 2 3 4 5 6 7 8 9 10 I 2 3 4 5 6 7 8 9 10 Ft-Fs in. H 0 1. 31 1. 31 1. 31 I . 26 1. 20...

Mount, Glynn O., Jr

2012-06-07T23:59:59.000Z

96

E-Print Network 3.0 - advanced vortex element Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

method of plasma Summary: with the new simple explanation of the energy separation in vortex tubes described here. Advanced numerical... vortex method of plasma insulation and...

97

E-Print Network 3.0 - accelerated vortex ring Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

left behind... forces were derived from the vortex rings, assuming all propulsive energy to be compiled in the rings... , ending up in a separate vortex ... Source:...

98

Transverse energy circulation and the edge diffraction of an optical vortex beam  

Science Journals Connector (OSTI)

Edge diffraction of a circular Laguerre–Gaussian beam represents an example of the optical vortex symmetry breakdown in which the hidden “vortex” energy...

Bekshaev, Aleksandr Ya; Mohammed, Kadhim A; Kurka, Ivan A

2014-01-01T23:59:59.000Z

99

All Skate, Now Reverse  

E-Print Network (OSTI)

All Skate, Now Reverse is a memoir that consists of personal narratives that are set in or are about my growing up in Nebraska. It is about life and its defining moments, and the collection summons up childhood epiphanies ...

Glover, Angela l.

2008-07-28T23:59:59.000Z

100

Reverse Osmosis Process  

Science Journals Connector (OSTI)

An empirical modeling method has been suggested for the reverse osmosis process. Least-square fitting of data to a third-order’ polynomial has resulted in the accurate modeling of Du Pont’s hollow fiber B-10 m...

Prof. Dr. Anthony Delyannis; Dr. Euridike-Emmy Delyannis

1980-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Reverse Osmosis Membranes  

Science Journals Connector (OSTI)

A bibliography of citations from the U.S. National Technical Information Service data base with 183 abstracts on membranes for reverse osmosis desalination, electro-dialysis desalination and other osmotic desa...

Prof. Dr. Anthony Delyannis; Dr. Euridike-Emmy Delyannis

1980-01-01T23:59:59.000Z

102

Finned Tube With Vortex Generators For A Heat Exchanger.  

DOE Patents (OSTI)

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.

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

2004-09-14T23:59:59.000Z

103

ENERGY LEVEL SPECTROSCOPY OF A BOUND VORTEX-ANTIVORTEX PAIR  

E-Print Network (OSTI)

vortex- antivortex (VAV) state in an annular Josephson junction. The bound VAV pair is formed microwave spectroscopy. Keywords: Macroscopic quantum effects, long Josephson junctions, vortex­9]. Most of the studied systems, such as dc-biased Josephson junctions (JJ), supercon- ducting quantum

Wallraff, Andreas

104

Dynamics of Magnetized Vortex Tubes in the Solar Chromosphere  

E-Print Network (OSTI)

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...

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

2012-01-01T23:59:59.000Z

105

Reversible collisionless magnetic reconnection  

SciTech Connect

Reversible magnetic reconnection is demonstrated for the first time by means of gyrokinetic numerical simulations of a collisionless magnetized plasma. Growth of a current-driven instability in a sheared magnetic field is accompanied by magnetic reconnection due to electron inertia effects. Following the instability growth, the collisionless reconnection is accelerated with development of a cross-shaped structure of current density, and then all field lines are reconnected. The fully reconnected state is followed by the secondary reconnection resulting in a weakly turbulent state. A time-reversed simulation starting from the turbulent state manifests that the collisionless reconnection process proceeds inversely leading to the initial state. During the reversed reconnection, the kinetic energy is reconverted into the original magnetic field energy. In order to understand the stability of reversed process, an external perturbation is added to the fully reconnected state, and it is found that the accelerated reconnection is reversible when the deviation of the E × B streamlines due to the perturbation is comparable with or smaller than a current layer width.

Ishizawa, A.; Watanabe, T.-H. [National Institute for Fusion Science, Toki 509-5292 (Japan)] [National Institute for Fusion Science, Toki 509-5292 (Japan)

2013-10-15T23:59:59.000Z

106

Flow reversal power limit for the HFBR  

SciTech Connect

The High Flux Beam Reactor (HFBR) is a pressurized heavy water moderated and cooled research reactor that began operation at 40 MW. The reactor was subsequently upgraded to 60 MW and operated at that level for several years. The reactor undergoes a buoyancy-driven reversal of flow in the reactor core following certain postulated accidents. Questions which were raised about the afterheat removal capability during the flow reversal transition led to a reactor shutdown and subsequent resumption of operation at a reduced power of 30 MW. An experimental and analytical program to address these questions is described in this report. The experiments were single channel flow reversal tests under a range of conditions. The analytical phase involved simulations of the tests to benchmark the physical models and development of a criterion for dryout. The criterion is then used in simulations of reactor accidents to determine a safe operating power level. It is concluded that the limit on the HFBR operating power with respect to the issue of flow reversal is in excess of 60 MW. Direct use of the experimental results and an understanding of the governing phenomenology supports this conclusion.

Cheng, L.Y.; Tichler, P.R.

1997-01-01T23:59:59.000Z

107

Electromagnetic Behavior of the Vortex Sponge  

Science Journals Connector (OSTI)

In an introductory paper the vortex sponge was shown to be governed in restricted cases by Maxwell's free-space equations. In the present paper analogs to electric and magnetic energies and Poynting's theorem are derived by simple mechanical considerations. Rotational stability suggested originally by MacCullagh as a fundamental property of a luminiferous ether turns out to be a quality of the medium as do the stresses introduced by Faraday and Maxwell to explain the mechanical actions of electric and magnetic fields. A rudimentary model for the electrostatic field is suggested on this basis. A conventional definition of charge and the laws of Coulomb and Biot complete Maxwell's equations for cases including charges and currents. A model of the magnetic field based on the bulk rotation and the Faraday-Maxwell stresses combined with the laws of Coulomb and Biot permits the inference of the Lorentz force. Although numerous gaps occur in the treatment it seems not unlikely that the vortex sponge has the qualities described by the electromagnetic field equations as well as the mechanical attributes required for a model of these fields.

Edward M. Kelly

1964-01-01T23:59:59.000Z

108

Irreversible flow of vortex matter: Polycrystal and amorphous phases Paolo Moretti and M.-Carmen Miguel  

E-Print Network (OSTI)

systems exhibiting this phenomenol- ogy, flux line vortex lattices in type II superconductors rep- resent

Miguel-Lopez, Carmen

109

Potential Flow Model of a Vortex Street Near a Fish-like Body  

E-Print Network (OSTI)

Potential Flow Model of a Vortex Street Near a Fish-like Body Joshua Brulé, University of Maryland to inviscid, irrotational solutions of Navier-Stokes · Vortex potential: "A model of the lateral line of fish for vortex sensing." Ren Z, Mohseni K. 2012 #12;Vortex near a (circular) fish · (Insert your own spherical

Anlage, Steven

110

Vortex-vacancy interactions in two-dimensional easy-plane magnets G. M. Wysin  

E-Print Network (OSTI)

Vortex-vacancy interactions in two-dimensional easy-plane magnets G. M. Wysin Department of Physics of a magnetic vacancy site on a nearby magnetic vortex are analyzed on square, hexagonal and triangular lattices. When the vortex is centered on a vacancy, the critical anisotropies where the stable vortex structure

Wysin, Gary

111

MHK Technologies/Vortex Induced Vibrations Aquatic Clean Energy VIVACE |  

Open Energy Info (EERE)

Vortex Induced Vibrations Aquatic Clean Energy VIVACE Vortex Induced Vibrations Aquatic Clean Energy VIVACE < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Vortex Induced Vibrations Aquatic Clean Energy VIVACE.jpg Technology Profile Primary Organization Vortex Hydro Energy LLC Project(s) where this technology is utilized *MHK Projects/Marine Hydrodynamics Laboratory at the University of Michigan Technology Resource Click here Current/Tidal Technology Type Click here Reciprocating Device Technology Readiness Level Click here TRL 4: Proof of Concept Technology Description The VIVACE (Vortex Induced Vibrations Aquatic Clean Energy) device is based on the extensively studied phenomenon of Vortex Induced Vibrations (VIV), which was first observed five-hundred years ago by Leonardo DaVinci in the form of 'Aeolian Tones.' VIV results from vortices forming and shedding on the downstream side of a bluff body in a current. Vortex shedding alternates from one side to the other, thereby creating a vibration or oscillation. The VIV phenomenon is non-linear, which means it can produce useful energy at high efficiency over a wide range of current speeds and directions.This converter is unlike any existing technology, as it does not use turbines, propellers, or dams. VIVACE converts the horizontal hydrokinetic energy of currents into cylinder mechanical energy. The latter is then converted to electricity through electric power generators.

112

Time reversal communication system  

DOE Patents (OSTI)

A system of transmitting a signal through a channel medium comprises digitizing the signal, time-reversing the digitized signal, and transmitting the signal through the channel medium. The channel medium may be air, earth, water, tissue, metal, and/or non-metal.

Candy, James V. (Danville, CA); Meyer, Alan W. (Danville, CA)

2008-12-02T23:59:59.000Z

113

Reverse Coherent Information  

Science Journals Connector (OSTI)

In this Letter we define a family of entanglement distribution protocols assisted by feedback classical communication that gives an operational interpretation to reverse coherent information, i.e., the symmetric counterpart of the well-known coherent information. This leads to the definition of a new entanglement distribution capacity that exceeds the unassisted capacity for some interesting channels.

Raúl García-Patrón; Stefano Pirandola; Seth Lloyd; Jeffrey H. Shapiro

2009-05-29T23:59:59.000Z

114

Reverse Osmosis Optimization  

Energy.gov (U.S. Department of Energy (DOE))

Report assesses techniques for optimizing reverse osmosis (RO) systems to increase RO system performance and water efficiency. It provides a general description of RO systems, the influence of RO systems on water use, and key areas where RO systems can be optimized to reduce water and energy consumption.

115

Reconnection in orthogonally interacting vortex tubes: Direct numerical simulations and quantifications  

Science Journals Connector (OSTI)

The three?dimensional time evolution of two orthogonally offset cylindrical vortices of equal strength is simulated by solving the hyperviscosity?regularized incompressible Navier–Stokes equations. A Fourier pseudospectral method with a time?split integration scheme is used for the solution. Four runs with different Reynolds numbers ranging between 690–2100 are performed each with a resolution of 963 collocation points. The sequence of important physical processes and the evolution of local and global quantities such as vorticity velocity and mean?square strain rate are presented. It is found that the growth rate of the maximum vorticity is at most exponential. The Reynolds number dependence of the time scale of reconnection the vorticity growth rate and the time at which the maximum vorticity is attained are examined and differences between the present results and Saffman’s essentially two?dimensional model predictions are encountered and elucidated. The distributions of the eigenvalues ? ? ? and the corresponding eigenvectors s ? s ? s ? of the rate of strain tensor S i j are calculated at different times. It is found that as the mean?square strain rate ? increases during the evolution s ? and the vorticity vector ? are perfectly aligned and ?>0 in high ? regions. Strong temporal spatial and Reynolds number dependence of the strain fields is also seen. Evidence is presented that during reconnection the vorticity growth in newly forming bridges takes place in the vicinity of the upper stagnation line segment of the vortex dipole due to the nature of the vortex stretching term. Also examined is the initial finger formation and it is found that the initial nonuniform axial stretching and the displacement of the vortex cores due to a lift force play an important role in this process.

O. N. Boratav; R. B. Pelz; N. J. Zabusky

1992-01-01T23:59:59.000Z

116

Monopole-Antimonopole Chains and Vortex Rings  

E-Print Network (OSTI)

We consider static axially symmetric solutions of SU(2) Yang-Mills-Higgs theory. The simplest such solutions represent monopoles, multimonopoles and monopole-antimonopole pairs. In general such solutions are characterized by two integers, the winding number m of their polar angle, and the winding number n of their azimuthal angle. For solutions with n=1 and n=2, the Higgs field vanishes at m isolated points along the symmetry axis, which are associated with the locations of m monopoles and antimonopoles of charge n. These solutions represent chains of m monopoles and antimonopoles in static equilibrium. For larger values of n, totally different configurations arise, where the Higgs field vanishes on one or more rings, centered around the symmetry axis. We discuss the properties of such monopole-antimonopole chains and vortex rings, in particular their energies and magnetic dipole moments, and we study the influence of a finite Higgs self-coupling constant on these solutions.

Burkhard Kleihaus; Jutta Kunz; Yasha Shnir

2004-05-19T23:59:59.000Z

117

Integrated multi vector vortex beam generator  

E-Print Network (OSTI)

A novel method to generate and manipulate vector vortex beams in an integrated, ring resonator based geometry is proposed. We show numerically that a ring resonator, with an appropriate grating, addressed by a vertically displaced access waveguide emits a complex optical field. The emitted beam possesses a specific polarization topology, and consequently a transverse intensity profile and orbital angular momentum. We propose a combination of several concentric ring resonators, addressed with different bus guides, to generate arbitrary orbital angular momentum qudit states, which could potentially be used for classical and quantum communications. Finally, we demonstrate numerically that this device works as an orbital angular momentum sorter with an average cross-talk of -10 dB between different orbital angular momentum channels.

Sebastian A. Schulz; Taras Machula; Ebrahim Karimi; Robert W. Boyd

2013-03-19T23:59:59.000Z

118

Sustained Self-Reversal in the Reversed-Field Pinch  

Science Journals Connector (OSTI)

Spontaneous reversal of the toroidal field in a reversed-field pinch as a result of low-? (small J?J?) resisitive kink mode activity is investigated with use of a three-dimensional magnetohydrodynamics code. Helical and three-dimensional steady reversed states are obtained. In three dimensions quasisteady fluctuating states are observed above a critical value of the pinch parameter ?.

A. Y. Aydemir and D. C. Barnes

1984-03-12T23:59:59.000Z

119

Argonne CNM Highlight: Biofunctionalized magnetic-vortex microdiscs for  

NLE Websites -- All DOE Office Websites (Extended Search)

Biofunctionalized magnetic-vortex microdiscs for targeted cancer-cell destruction Biofunctionalized magnetic-vortex microdiscs for targeted cancer-cell destruction Magnetic microdisks Reflection optical microscope image of a dried suspension of the discs prepared via magnetron sputtering and optical lithography. Magnetic spin vortex Model of magnetic-vortex spin distribution in a disc. Users from Argonne's Materials Science Division and University of Chicago's Pritzker School of Medicine, working collaboratively on a user science project with CNM's Nanobio Interfaces Group, have discovered that nanostructured magnetic materials offer exciting avenues for probing cell mechanics, activating mechanosensitive ion channels, and advancing potential cancer therapies. Their new report describes an approach based on interfacing cells with lithographically defined microdiscs (1-micron

120

A study on passive methods of vortex induced vibrations suppression  

E-Print Network (OSTI)

A number of engineering systems, including those found in offshore operations, are often affected by vortex-induced vibrations (VIV). This phenomenon is caused by the interaction between a structure and shed vortices which ...

Galvao, Richardo A

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Experimental demonstration of vortex pancake in high temperature superconductor  

Science Journals Connector (OSTI)

In order to demonstrate the existence of the vortex pancake in high temperature superconductor experimentally, a configuration in which the current...E-j relation obtained with this electrodes spatial configurati...

Wei-xian Wang; Yu-heng Zhang

2006-09-01T23:59:59.000Z

122

MHK Technologies/SeaUrchin Vortex Reaction Turbine | Open Energy  

Open Energy Info (EERE)

SeaUrchin Vortex Reaction Turbine SeaUrchin Vortex Reaction Turbine < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage SeaUrchin Vortex Reaction Turbine.jpg Technology Profile Primary Organization Elemental Energy Technologies Limited ABN 46 128 491 903 Technology Resource Click here Current Technology Type Click here Axial Flow Turbine Technology Readiness Level Click here TRL 4 Proof of Concept Technology Description A revolutionary vortex reaction turbine branded the SeaUrchin an advanced third generation marine turbine technology capable of delivering inexpensive small to large scale baseload or predictable electricity by harnessing the kinetic energy of free flowing ocean currents tides and rivers Technology Dimensions Device Testing Date Submitted 55:15.2

123

Self-Consistent Electronic Structure of a dx2-y2 and a dx2-y2 + idxy Vortex  

Science Journals Connector (OSTI)

We investigate quasiparticle states associated with an isolated vortex in a d-wave superconductor using a self-consistent Bogoliubov–de Gennes formalism. For a pure dx2-y2 superconductor we find that there exist no bound states in the core; all the states are extended with continuous energy spectrum. This result is inconsistent with the existing experimental data on cuprates. We propose an explanation for this data in terms of a magnetic-field-induced dx2-y2+idxy state recently invoked in connection with the thermal conductivity measurements on Bi2Sr2CaCu2O8.

M. Franz and Z. Tešanovi?

1998-05-25T23:59:59.000Z

124

Nanoscale strain-induced pair suppression as a source of vortex pinning in high-temperature superconductors  

SciTech Connect

Boosting large-scale superconductor applications require nanostructured conductors with artificial pinning centres immobilizing quantized vortices at high temperature and magnetic fields. Here we demonstrate a highly effective mechanism of artificial pinning centres in solution-derived high-temperature superconductor nanocomposites through generation of nanostrained regions where Cooper pair formation is suppressed. The nanostrained regions identified from transmission electron microscopy devise a very high concentration of partial dislocations associated with intergrowths generated between the randomly oriented nanodots and the epitaxial YBa{sub 2}Cu{sub 3}O{sub 7} matrix. Consequently, an outstanding vortex-pinning enhancement correlated to the nanostrain is demonstrated for four types of randomly oriented nanodot, and a unique evolution towards an isotropic vortex-pinning behaviour, even in the effective anisotropy, is achieved as the nanostrain turns isotropic. We suggest a new vortex-pinning mechanism based on the bond-contraction pairing model, where pair formation is quenched under tensile strain, forming new and effective core-pinning regions.

Llordes, A. [ICMAB, Barcelona, Spain; Palau, A. [ICMAB, Barcelona, Spain; Vlad, R. [ICMAB, Barcelona, Spain; Pomar, A. [ICMAB, Barcelona, Spain; Arbiol, Jordi [ICMAB, Barcelona, Spain; Guzman, Roger [ICMAB, Barcelona, Spain; Gazquez Alabart, Jaume [ORNL; Varela del Arco, Maria [ORNL; Sandiumenge, Felip [ICMAB, Barcelona, Spain; Ricart, Susagna [ICMAB, Barcelona, Spain; Puig, Teresa [ICMAB, Barcelona, Spain; Chataigner, D. [CRISMAT, Caen, France; Vanacken, J. [INPAC-Institute for Nanoscale Physics and Chemistry, Leuven, Belgium; Gutierrez, J. [INPAC-Institute for Nanoscale Physics and Chemistry, Leuven, Belgium; Deutscher, G. [Tel Aviv University; Moschalkov, V. [INPAC-Institute for Nanoscale Physics and Chemistry, Leuven, Belgium; Obradors, Xavier [ICMAB, Barcelona, Spain

2012-01-01T23:59:59.000Z

125

Colloidal fouling of reverse osmosis membranes  

E-Print Network (OSTI)

the rate of fouling of reverse osmosis membranes treating32, 127-135. fouling of reverse osmosis membranes." Buros,Colloidal fouling of reverse osmosis membranes." J. Colloid

Elimelech, Menachem

1994-01-01T23:59:59.000Z

126

Reversible Fuel Cells Workshop | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Reversible Fuel Cells Workshop Reversible Fuel Cells Workshop The National Renewable Energy Laboratory hosted a workshop addressing the current state-of-the-art of reversible fuel...

127

Strain-induced time-reversal odd superconductivity in graphene  

E-Print Network (OSTI)

Time-reversal symmetry breaking superconductors are exotic phases of matter with fascinating properties, which are, however, encountered rather sparsely. Here we identify the possibility of realizing such a superconducting ground state that exhibits an $f+is$ pairing symmetry in strained graphene. Although the underlying attractive interactions need to be sufficiently strong and comparable in pristine graphene to support such pairing state, we argue that strain can be conducive for its formation even for weak interactions. We show that quantum-critical behavior near the transition is controlled by a multicritical point, characterized by various critical exponents computed here in the framework of an $\\epsilon$-expansion near four spacetime dimensions. Furthermore, a vortex in this mixed superconducting state hosts a pair of Majorana fermions supporting a quartet of insulating and superconducting orders, among which topologically nontrivial quantum spin Hall insulator. These findings suggest that strained graphene could provide a platform for the realization of exotic superconducting states of Dirac fermions.

Bitan Roy; Vladimir Juricic

2014-07-31T23:59:59.000Z

128

Reversal bending fatigue testing  

SciTech Connect

Embodiments for apparatuses for testing reversal bending fatigue in an elongated beam are disclosed. Embodiments are configured to be coupled to first and second end portions of the beam and to apply a bending moment to the beam and create a pure bending condition in an intermediate portion of the beam. Embodiments are further configured to cyclically alternate the direction of the bending moment applied to the beam such that the intermediate portion of the beam cyclically bends in opposite directions in a pure bending condition.

Wang, Jy-An John; Wang, Hong; Tan, Ting

2014-10-21T23:59:59.000Z

129

Ultra-Low NOx Advanced Vortex Combustor  

SciTech Connect

An ultra 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 (USDOE NETL) test facility 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/UHC emissions of 4/4/0 ppmv (all emissions are at 15% O2 dry). The design also achieved less than 3 ppmv NOx with combustion efficiencies in excess of 99.5%. The design demonstrated tremendous 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, a pressure drop of 1.75% was measured which is significantly lower than conventional gas turbine combustors. Potentially, this lower pressure drop characteristic of the AVC concept translates into overall gas turbine cycle efficiency improvements of up to one full percentage point. The relatively high velocities and low pressure drops achievable with this technology make the AVC approach an attractive alternative for syngas fuel applications.

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

2006-05-01T23:59:59.000Z

130

ULTRA-LOW NOX ADVANCED VORTEX COMBUSTOR  

SciTech Connect

An ultra 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 (USDOE NETL) test facility 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/UHC emissions of 4/4/0 ppmv (all emissions are at 15% O2 dry). The design also achieved less than 3 ppmv NOx with combustion efficiencies in excess of 99.5%. The design demonstrated tremendous 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, a pressure drop of 1.75% was measured which is significantly lower than conventional gas turbine combustors. Potentially, this lower pressure drop characteristic of the AVC concept translates into overall gas turbine cycle efficiency improvements of up to one full percentage point. The relatively high velocities and low pressure drops achievable with this technology make the AVC approach an attractive alternative for syngas fuel applications.

Ryan G. Edmonds; Robert C. Steele; Joseph T. Williams; Douglas L. Straub; Kent H. Casleton; Avtar Bining

2006-05-01T23:59:59.000Z

131

Wave–vortex interactions in the nonlinear Schrödinger equation  

SciTech Connect

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.

Guo, Yuan, E-mail: yuanguo@cims.nyu.edu; Bühler, Oliver [Courant Institute of Mathematical Sciences, New York University, New York, New York 10012 (United States)] [Courant Institute of Mathematical Sciences, New York University, New York, New York 10012 (United States)

2014-02-15T23:59:59.000Z

132

Experimental Investigations of Vortex Induced Vibration of A Flat Plate in Pitch Oscillation  

E-Print Network (OSTI)

A bluff structure placed in a flowing fluid, may be subjected to vortex-induced vibrations (VIV). For a flat plate with only rotational degree of freedom, the VIV is rotational oscillation. Based on the experimental investigation, vortex...

Yang, Yi

2012-02-14T23:59:59.000Z

133

Generation and Propagation of Inertia Gravity Waves from Vortex Dipoles and Jets Shuguang Wang  

E-Print Network (OSTI)

Generation and Propagation of Inertia Gravity Waves from Vortex Dipoles and Jets Shuguang Wang generation and propagation from jets within idealized vortex dipoles using a nonhydrostatic mesoscale model, moist convection, fronts, upper level jets, geostrophic adjustment and spontaneous generation (Fritts

134

Reverse slapper detonator  

DOE Patents (OSTI)

A reverse slapper detonator (70), and methodology related thereto, are provided. The detonator (70) is adapted to be driven by a pulse of electric power from an external source (80). A conductor (20) is disposed along the top (14), side (18), and bottom (16) surfaces of a sheetlike insulator (12). Part of the conductor (20) comprises a bridge (28), and an aperture (30) is positioned within the conductor (20), with the bridge (28) and the aperture (30) located on opposite sides of the insulator (12). A barrel (40) and related explosive charge (50) are positioned adjacent to and in alignment with the aperture (30), and the bridge (28) is buttressed with a backing layer (60). When the electric power pulse vaporizes the bridge (28), a portion of the insulator (12) is propelled through the aperture (30) and barrel (40), and against the explosive charge (50), thereby detonating it.

Weingart, Richard C. (Livermore, CA)

1990-01-01T23:59:59.000Z

135

Reverse Osmosis Optimization  

SciTech Connect

This technology evaluation was prepared by Pacific Northwest National Laboratory on behalf of the U.S. Department of Energy’s Federal Energy Management Program (FEMP). ¬The technology evaluation assesses techniques for optimizing reverse osmosis (RO) systems to increase RO system performance and water efficiency. This evaluation provides a general description of RO systems, the influence of RO systems on water use, and key areas where RO systems can be optimized to reduce water and energy consumption. The evaluation is intended to help facility managers at Federal sites understand the basic concepts of the RO process and system optimization options, enabling them to make informed decisions during the system design process for either new projects or recommissioning of existing equipment. This evaluation is focused on commercial-sized RO systems generally treating more than 80 gallons per hour.¬

McMordie Stoughton, Kate; Duan, Xiaoli; Wendel, Emily M.

2013-08-26T23:59:59.000Z

136

Properly apply reverse osmosis  

SciTech Connect

Reverse osmosis (RO) is a water purification technique used to reduce the loading of dissolved solids in solution. The popularity of RO for treating boiler feedwater is growing because of the rising cost of ion-exchange-based demineralization as well as safety concerns associated with handling acid and caustic. A properly designed and operated RO-based boiler-feedwater-treatment system can reduce the load to, and costs associated with, ion exchange demineralization. This article discusses RO feedwater quality recommendations, pretreatment techniques, and system monitoring necessary to achieve optimum RO system performance in the most cost-effective manner. Regardless of the application--whether it is the treatment of boiler feedwater, industrial wastewater, or process water--the approach to pretreatment and the other design and operating guidance offered here remains the same.

Kucera, J.

1997-02-01T23:59:59.000Z

137

PHYSICAL REVIEW B 85, 134414 (2012) Nonlinear motion of magnetic vortex cores during fast magnetic pulses  

E-Print Network (OSTI)

pulses Keiki Fukumoto* Japan Synchrotron Radiation Research Institute, Sayo, Hyogo 679-5198, Japan 351-0198, Japan Toyohiko Kinoshita Japan Synchrotron Radiation Research Institute, Sayo, Hyogo 679 Kuniaki Arai Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan

Otani, Yoshichika

138

A constant shear stress core flow model of the bidirectional vortex  

Science Journals Connector (OSTI)

...Chiaverini, M. J., Sauer, J. A. Knuth, W. H. 2004 Numerical code development for simulating gel propellant combustion processes. JANNAF Paper (unclassified). Ogawa, A 1984Estimation of the collection efficiencies of the three types of...

2009-01-01T23:59:59.000Z

139

Sandia National Laboratories: reverse osmosis  

NLE Websites -- All DOE Office Websites (Extended Search)

reverse osmosis ECIS-UNM: Biomimetic Membranes for Water Purification On February 20, 2013, in Advanced Materials Laboratory, Energy Efficiency, Facilities, Global Climate &...

140

Core Drilling Demonstration  

Energy.gov (U.S. Department of Energy (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...

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Mutual Chern-Simons gauge theory of spontaneous vortex phase  

Science Journals Connector (OSTI)

We apply the mutual Chern-Simons effective theory [Kou, Qi, and Weng, Phys. Rev. B 71, 235102 (2005)] of the doped Mott insulator to the study of the so-called spontaneous vortex phase in the low-temperature pseudogap region, which is characterized by strong unconventional superconducting fluctuations. An effective description for the spontaneous vortex phase is derived from the general mutual Chern-Simons Lagrangian, based on which the physical properties including the diamagnetism, spin paramagnetism, magnetoresistance, and the Nernst coefficient, have been quantitatively calculated. The phase boundaries of the spontaneous vortex phase, which sits between the onset temperature Tv and the superconducting transition temperature Tc, are also determined within the same framework. The results are consistent with the experimental measurements of the cuprates.

Xiao-Liang Qi and Zheng-Yu Weng

2007-09-07T23:59:59.000Z

142

Ubiquitous Solar Eruptions Driven by Magnetized Vortex Tubes  

E-Print Network (OSTI)

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.

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

2013-01-01T23:59:59.000Z

143

The effect of surface tension on the Moore singularity of vortex sheet dynamics  

E-Print Network (OSTI)

The effect of surface tension on the Moore singularity of vortex sheet dynamics F. de la Hoz , M's singularities by surface tension in the evolution of vortex sheets and its dependence on Weber number (which is inversely proportional to surface tension coefficient). The curvature of the vortex sheet, instead

Fontelos, Marco

144

Traveling Waves from the Arclength Parameterization: Vortex Sheets with Surface Tension  

E-Print Network (OSTI)

Traveling Waves from the Arclength Parameterization: Vortex Sheets with Surface Tension Benjamin for the vortex sheet with surface tension. We use the angle- arclength description of the interface rather than prove that there exist traveling vortex sheets with surface tension bifurcating from equilibrium. We

Wright, J. Douglas

145

CALTECH ASCI TECHNICAL REPORT 129 On Velocity Structure Functions and the Spherical Vortex Model for  

E-Print Network (OSTI)

the stretched-spiral vortex has been suc- cessfully applied to the calculation of the energy spectrum,6 and some for larger scales is perhaps questionable. Most quantitative vortex-based models have utilized tube and sheetCALTECH ASCI TECHNICAL REPORT 129 On Velocity Structure Functions and the Spherical Vortex Model

Barr, Al

146

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

E-Print Network (OSTI)

, reconnections of stream lines, vortex lines and magnetic flux tubes change the topology of the flowVortex reconnections in atomic condensates at finite temperature A. J. Allen1 , S. Zuccher2 , M (Dated: May 28, 2014) The study of vortex reconnections is an essential ingredient of understanding

Zuccher, Simone

147

Vortex Formation in a Plasma Interacting with Neutral Flow  

SciTech Connect

Recently, it has been observed that there exists a class of vortices which rotates in the opposite direction to ExB drift (referred to as anti-ExB vortex). This result suggests that a predominant force other than electric field is acting on ions. It is found that momentum transport and resultant force generation through the interaction between ions and neutral flow play an essential role on anti-ExB vortex formation. The existence of inward neutral flow, which drives the ions in the anti-ExB direction, has been confirmed using a newly-developed high-resolution laser induced fluorescence (LIF) spectroscopy system.

Tanaka, M. Y.; Ogiwara, K.; Etoh, S. [Department of High Energy Engineering Science, Kyushu University, Kasuga-koen 6-1, Kasuga 816-8580 (Japan); Aramaki, M. [Department of Electrical Engineering, Nagoya University, Chikusa, Nagoya 464-8603 (Japan); Yoshimura, S. [National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292 (Japan); Varanjes, J. [Center for Plasma Astrophysics, Celestijnenlaan 200 B 3001 Leuven (Belgium)

2008-10-15T23:59:59.000Z

148

Laboratory Analysis of Vortex Dynamics For Shallow Tidal Inlets  

E-Print Network (OSTI)

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 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...

Whilden, Kerri Ann

2010-10-12T23:59:59.000Z

149

Revival of Classical Vortex Generators Now for Transition Delay  

Science Journals Connector (OSTI)

Classical vortex generators, known for their efficiency in delaying or even inhibiting boundary layer separation, are here shown to be coveted devices for transition to turbulence delay. The present devices are miniature with respect to classical vortex generators but are tremendously powerful in modulating the laminar boundary layer in the direction orthogonal to the base flow and parallel to the surface. The modulation generates an additional term in the perturbation energy equation, which counteracts the wall-normal production term and, hence, stabilizes the flow. Our experimental results show that these devices are really effective in delaying transition, but we also reveal their Achilles’ heel.

Shahab Shahinfar; Sohrab S. Sattarzadeh; Jens H. M. Fransson; Alessandro Talamelli

2012-08-16T23:59:59.000Z

150

Reversible micromachining locator  

DOE Patents (OSTI)

This invention provides a device which includes a locator, a kinematic mount positioned on a conventional tooling machine, a part carrier disposed on the locator and a retainer ring. The locator has disposed therein a plurality of steel balls, placed in an equidistant position circumferentially around the locator. The kinematic mount includes a plurality of magnets which are in registry with the steel balls on the locator. In operation, a blank part to be machined is placed between a surface of a locator and the retainer ring (fitting within the part carrier). When the locator (with a blank part to be machined) is coupled to the kinematic mount, the part is thus exposed for the desired machining process. Because the locator is removably attachable to the kinematic mount, it can easily be removed from the mount, reversed, and reinserted onto the mount for additional machining. Further, the locator can likewise be removed from the mount and placed onto another tooling machine having a properly aligned kinematic mount. Because of the unique design and use of magnetic forces of the present invention, positioning errors of less than 0.25 micrometer for each machining process can be achieved. 7 figs.

Salzer, L.J.; Foreman, L.R.

1999-08-31T23:59:59.000Z

151

Modelling Reverse Osmosis  

Science Journals Connector (OSTI)

After a brief presentation of the principal kinetic and thermodynamic aspects of the theory of reverse osmosis, the present review examines various physicochemical mechanisms of the selectivity of membranes with respect to electrolyte solutions: the electrochemical mechanism, related to the charge of the pore surface; the dielectric exclusion of ions, due to image forces; and the structural mechanism, due to the change in the properties of water in fine hydrophilic pores. Methods for calculating the changes in the standard chemical potentials of ions on entering the membrane phase, and the effects of the Donnan exclusion of ions with allowance for the different charge of the membrane have been described. It has been concluded that it is appropriate to use charged membranes to separate electrolyte solutions at low concentrations. The problem of the transport of solutions through the fine pores of membranes has been formulated, taking account of the equilibrium distribution coefficients of the ions, their mobility, the charge of the membrane, and the phenomenon of concentration polarisation. Routes to the further development of the theory as applied to membranes of different types, different compositions, and solution concentrations have been discussed. The bibliography contains 84 references.

S S Dukhin; Nikolai V Churaev; V N Shilov; Viktor M Starov

1988-01-01T23:59:59.000Z

152

HYDRATE CORE DRILLING TESTS  

SciTech Connect

The ''Methane Hydrate Production from Alaskan Permafrost'' project is a three-year endeavor being conducted by Maurer Technology Inc. (MTI), Noble, and Anadarko Petroleum, in partnership with the U.S. DOE National Energy Technology Laboratory (NETL). The project's goal is to build on previous and ongoing R&D in the area of onshore hydrate deposition. The project team plans to design and implement a program to safely and economically drill, core and produce gas from arctic hydrates. The current work scope includes drilling and coring one well on Anadarko leases in FY 2003 during the winter drilling season. A specially built on-site core analysis laboratory will be used to determine some of the physical characteristics of the hydrates and surrounding rock. Prior to going to the field, the project team designed and conducted a controlled series of coring tests for simulating coring of hydrate formations. A variety of equipment and procedures were tested and modified to develop a practical solution for this special application. This Topical Report summarizes these coring tests. A special facility was designed and installed at MTI's Drilling Research Center (DRC) in Houston and used to conduct coring tests. Equipment and procedures were tested by cutting cores from frozen mixtures of sand and water supported by casing and designed to simulate hydrate formations. Tests were conducted with chilled drilling fluids. Tests showed that frozen core can be washed out and reduced in size by the action of the drilling fluid. Washing of the core by the drilling fluid caused a reduction in core diameter, making core recovery very difficult (if not impossible). One successful solution was to drill the last 6 inches of core dry (without fluid circulation). These tests demonstrated that it will be difficult to capture core when drilling in permafrost or hydrates without implementing certain safeguards. Among the coring tests was a simulated hydrate formation comprised of coarse, large-grain sand in ice. Results with this core showed that the viscosity of the drilling fluid must also be carefully controlled. When coarse sand was being cored, the core barrel became stuck because the drilling fluid was not viscous enough to completely remove the large grains of sand. These tests were very valuable to the project by showing the difficulties in coring permafrost or hydrates in a laboratory environment (as opposed to a field environment where drilling costs are much higher and the potential loss of equipment greater). Among the conclusions reached from these simulated hydrate coring tests are the following: Frozen hydrate core samples can be recovered successfully; A spring-finger core catcher works best for catching hydrate cores; Drilling fluid can erode the core and reduces its diameter, making it more difficult to capture the core; Mud must be designed with proper viscosity to lift larger cuttings; and The bottom 6 inches of core may need to be drilled dry to capture the core successfully.

John H. Cohen; Thomas E. Williams; Ali G. Kadaster; Bill V. Liddell

2002-11-01T23:59:59.000Z

153

Reverse osmosis reverses conventional wisdom with Superfund cleanup success  

SciTech Connect

Although widely recognized as the most efficient means of water purification, reverse osmosis has not been considered effective for remediating hazardous wastewater. Scaling and fouling, which can cause overruns and downtime, and require membrane replacement, have inhibited success in high-volume wastewater applications. Despite this background, a reverse osmosis technology developed in Europe recently was used successfully to treat large volumes of contaminated water at a major Superfund site in Texas. The technology's success there may increase the chances for reverse osmosis to find wider use in future cleanups and other waste treatment applications.

Collins, M. (French Ltd. Task Group, Crosby, TX (United States)); Miller, K. (Rochem Environmental Inc., Houston, TX (United States))

1994-09-01T23:59:59.000Z

154

New vortex ring configurations for the MAP dyon solutions  

Science Journals Connector (OSTI)

Electrically charged magnetic solutions of SU (2) Yang-Mills-Higgs theory with net zero topological charge has been obtained as axially symmetric saddle-point solutions in Ref. [1]. These solutions are characterized by an integer the winding number n of their azimuthal angle ? and an electric charge parameter 0vortex ring configuration with n=2 ?=0.65 and varying Higgs field strength. Our observations showed that beside the fundamental solution which is an electrically charged MAP solution there also exist two other branches of eclectically charged vortex ring solutions which both appear at ?=20.45. The difference in total energy between these two branches of solution is very small but the difference in diameter of vortex rings of the two branches is quite significant. Finding of a branching phenomena in presence of a fundamental MAP solution has been for the first time. In Ref. [2] new branching solutions occur for the electrically neutral case in presence of fundamental vortex ring solutions but not for the fundamental MAP solution.

2014-01-01T23:59:59.000Z

155

Creation and pinning of vortex-antivortex pairs  

E-Print Network (OSTI)

Computer modeling is reported about the creation and pinning of a magnetic vortex-antivortex (V-AV) pair in a superconducting thin film, due to the magnetic field of a vertical magnetic dipole above the film, and two antidot pins inside the film...

Kim, Sangbum; Hu, Chia-Ren; Andrews, Malcolm J.

2006-01-01T23:59:59.000Z

156

Vortex trimer in three-component Bose-Einstein condensates  

E-Print Network (OSTI)

Vortex trimer is predicted in three-component Bose-Einstein condensates with internal coherent couplings. The molecule is made by three constituent vortices which are bounded by domain walls of the relative phases. We show that the shape and the size of the molecule can be controlled by changing the internal coherent couplings.

Minoru Eto; Muneto Nitta

2012-01-01T23:59:59.000Z

157

High-Resolution Simulations of Parallel BladeVortex Interactions  

E-Print Network (OSTI)

= perturbation pressure coefficient, p ps= 1 2 1U2 1 c = rotor blade chord p = instantaneous airfoil surface­vortex interaction computations Introduction A MAJOR source of rotorcraft noise is generated by the rotor blades on the rotor blades. BVI noise is especially important because it is known to propagate out

Alonso, Juan J.

158

WAVE-VORTEX INTERACTIONS IN THE ATMOSPHERE, AND CLIMATE  

E-Print Network (OSTI)

parcel dynamics, linear modes, balan- ced models, gravity waves, weather and climate prediction Introduction Numerical weather and climate prediction is complicated because only the flow scales larger thanWAVE-VORTEX INTERACTIONS IN THE ATMOSPHERE, AND CLIMATE PREDICTION Onno Bokhove Numerical Analysis

Vellekoop, Michel

159

Modified Black Hole with Polar Jet and Vortex  

E-Print Network (OSTI)

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.

T. Tmmalm

2001-12-06T23:59:59.000Z

160

Vortex strings in electric dipole radiation near a mirror  

Science Journals Connector (OSTI)

Abstract The energy flow pattern of the radiation emitted by an oscillating electric dipole near a mirror has a complicated structure, including numerous singularities and vortices. We consider the flow lines of energy in the plane through the surface normal and the oscillation direction of the dipole. It is shown that the vortices are due to the vanishing of the magnetic field at their centers. The locations of the vortices have the appearance of beads on strings, and there are four such strings. The rotation direction of the energy flow for each vortex on a given string is the same. There are two strings with clockwise rotation and two strings with counterclockwise rotation. Field lines of energy flow either start or end at the center of a vortex. For a given string, field lines end at each vortex or field lines start at each vortex. There are two strings on which field lines end at the centers of the vortices, and there are two strings on which field lines start inside the vortices.

Xin Li; Henk F. Arnoldus

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Tailoring magnetic properties of core/shell nanoparticles and Shouheng Sun  

E-Print Network (OSTI)

in electromagnetic and permanent magnetic applications.10,11 In such a system, the intimate contact be- tween the core and shell leads to effective exchange coupling and therefore cooperative magnetic switching coupled and magneti- zation of both core and shell reverses cooperatively. As a result, the magnetic

Liu, J. Ping

162

Observations on Buoyant Convection in Reverse Osmosis  

Science Journals Connector (OSTI)

Observations on Buoyant Convection in Reverse Osmosis ... Buoyancy Effects in Dead-End Reverse Osmosis:? Visualization by Holographic Interferometry ... Buoyancy Effects in Dead-End Reverse Osmosis:? Visualization by Holographic Interferometry ...

Terry J. Hendricks; Jean F. Macquin; Forman A. Williams

1972-05-01T23:59:59.000Z

163

Reversible concentric ring microfluidic interconnects  

E-Print Network (OSTI)

A reversible, Chip-to-Chip microfluidic interconnect was designed for use in high temperature, high pressure applications such as chemical microreactor systems. The interconnect uses two sets of concentric, interlocking ...

Thompson, Mary Kathryn, 1980-

2004-01-01T23:59:59.000Z

164

Microporous glasses for reverse osmosis  

Science Journals Connector (OSTI)

The preparation, heat-treatment and leaching of phase separable borosilicate glasses which are of interest as possible semipermeable membranes for reverse osmosis applications are described. It is shown that ... ...

P. W. McMillan; C. E. Matthews

1976-01-01T23:59:59.000Z

165

Reversible Dehydrogenation of Magnesium Borohydride to Magnesium...  

NLE Websites -- All DOE Office Websites (Extended Search)

Reversible Dehydrogenation of Magnesium Borohydride to Magnesium Triborane in the Solid State Under Moderate Conditions. Reversible Dehydrogenation of Magnesium Borohydride to...

166

Hollow-Fiber Reverse Osmosis Membranes  

Science Journals Connector (OSTI)

Hollow-fiber membranes for reverse osmosis desalination are typically of the dense wall ... compact modules and further improve the economics of reverse osmosis desalination.

Mark E. Cohen; Michael A. Grable; Billy M. Riggleman

1972-01-01T23:59:59.000Z

167

Vortex motion in Josephson-junction arrays near f=0 and f=1/2  

Science Journals Connector (OSTI)

We study vortex motion in two-dimensional Josephson arrays at magnetic fields near zero and one-half flux quanta per plaquette (f=0 and f=1/2). The array is modeled as a network of resistively and capacitively shunted Josephson junctions at temperature T=0. Calculations are carried out over a range of the McCumber-Stewart junction damping parameter ?. Near both f=0 and f=1/2, the I-V characteristics exhibit two critical currents, Ic1(f) and Ic2(f), representing the critical current for depinning a single vortex, and for depinning the entire ground-state phase configuration. Near f=0, single vortex motion just above Ic1(0) leads to Josephson-like voltage oscillations. The motion of the vortex is seemingly overdamped (i.e., nonhysteretic) even when the individual junction parameters are highly underdamped, in agreement with experiments. At sufficiently large ?, and sufficiently high vortex velocity, the vortex breaks up into a row of resistively switched junctions perpendicular to the current. Near f=1/2, the vortex potential, and corresponding vortex trajectories, are more complicated than near f=0. Nevertheless, the vortex is still ‘‘overdamped’’ even when the individual junctions are highly underdamped, and there is still row-switching behavior at large values of ?. A high-energy vortex in a very underdamped array tends to generate resistively switched rows rather than to move ballistically. Some possible explanations for this behavior are discussed.

Wenbin Yu; K. H. Lee; D. Stroud

1993-03-01T23:59:59.000Z

168

Vortex properties in superconducting Nb/Pd multilayers  

Science Journals Connector (OSTI)

We have investigated the upper critical magnetic field Hc2, the critical current density Jc, and the pinning force Fp in sputtered Nb/Pd multilayers, varying the temperatures T, the Pd thicknesses dPd and the magnetic field H orientation (parallel and perpendicular to the plane of the sample). In perpendicular fields, the vortex dynamics was strongly influenced by grain-boundary pinning. In parallel fields, a peak was observed in the Jc(H) curves for samples with Pd thicknesses dPd>100 Å. After comparing the experimental results with the existing theories, we have related the presence of this peak effect to the matching of vortex kinks with the layered artificial structure.

C. Coccorese; C. Attanasio; L. V. Mercaldo; M. Salvato; L. Maritato; J. M. Slaughter; C. M. Falco; S. L. Prischepa; B. I. Ivlev

1998-04-01T23:59:59.000Z

169

Higher Derivative Corrections to Non-Abelian Vortex Effective Theory  

E-Print Network (OSTI)

We give a systematic method to calculate higher derivative corrections to low-energy effective theories of solitons, which are in general non-linear sigma models on the moduli spaces of the solitons. By applying it to the effective theory of a single BPS non-Abelian vortex in U(N) gauge theory with N fundamental Higgs fields, we obtain four derivative corrections to the effective sigma model on the moduli space C \\times CP^{N-1}. We compare them with the Nambu-Goto action and the Faddeev-Skyrme model. We also show that Yang-Mills instantons/monopoles trapped inside a non-Abelian vortex membrane/string are not modified in the presence of higher derivative terms.

Minoru Eto; Toshiaki Fujimori; Muneto Nitta; Keisuke Ohashi; Norisuke Sakai

2012-04-03T23:59:59.000Z

170

Precession of a single vortex line in superfluid B3  

Science Journals Connector (OSTI)

This paper reports the discovery of a new vortex phenomenon in superfluid B3. A single filament of quantized vortex line precesses as a solid body around a wire extending along the axis of a cylinder. The precession frequency equals the angular velocity of the apparatus at which the presence of a single quantum of circulation minimizes the system’s free energy. The period of precession is related to the circulation quantum and the dimensions of the apparatus. Thus a measurement of the precession period is an accurate determination of the quantum unit. We find ?=(1.020±0.03)h/2m3, where m3 is the mass of the He3 atom.

R. J. Zieve; Yu. Mukharsky; J. D. Close; J. C. Davis; R. E. Packard

1992-03-02T23:59:59.000Z

171

MHK Technologies/Vortex Oscillation | Open Energy Information  

Open Energy Info (EERE)

Oscillation Oscillation < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Vortex Oscillation.jpg Technology Profile Primary Organization Vortex Oscillation Technology Ltd Technology Resource Click here Current Technology Type Click here Attenuator Technology Readiness Level Click here TRL 1 3 Discovery Concept Def Early Stage Dev Design Engineering Technology Description If cylinder or another body is fixed on a moving bonding this force can set the body or its separate parts into oscillation e g elastic slat If the system of mechanical energy output is organized correctly this device can be considered as generator Technology Dimensions Device Testing Date Submitted 08:12.7 << Return to the MHK database homepage Retrieved from

172

-The Core of CS -Curricula  

E-Print Network (OSTI)

- Advanced Courses #12;The Core of CS Curricula #12;CS Body of Knowledge Area > Unit > Topic Core vs elective#12;ACM vs U S I #12;- The Core of CS - Curricula - Introductory Courses - Intermediate Courses Introductory Intermediate Advanced Core Elective Units #12;Courses Introductory Intermediate Advanced Core

Hauswirth, Matthias

173

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

174

Coherence Current, Coherence Vortex, and the Conservation Law of Coherence  

Science Journals Connector (OSTI)

Introducing scalar and vector densities for a mutual coherence function, we present a new conservation law for optical coherence of scalar wave fields in the form of a continuity equation. This coherence conservation law provides new insights into topological phenomena for the complex coherence function. Some properties related to the newly introduced coherence vector density, such as a circulating coherence current associated with a coherence vortex, are investigated both theoretically and experimentally for the first time.

Wei Wang and Mitsuo Takeda

2006-06-08T23:59:59.000Z

175

Core shroud corner joints  

DOE Patents (OSTI)

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

Gilmore, Charles B.; Forsyth, David R.

2013-09-10T23:59:59.000Z

176

Transient vortex events in the initial value problem for turbulence  

E-Print Network (OSTI)

A vorticity surge event that could be a paradigm for a wide class of bursting events in turbulence is studied to examine how the energy cascade is established and how this event could serve as a new test of LES turbulence models. This vorticity surge event is tied to the formation of the energy cascade in a direct numerical simulation by the traditional signatures of a turbulent energy cascade such as spectra approaching -5/3 and strongly Beltramized vortex tubes. A coherent mechanism is suggested by the nearly simultaneous development of a maximum of the peak vorticity $\\|\\omega\\|_\\infty$, growth of the dissipation, the appearance of a helically aligned local vortex configuration and strong, transient oscillations in the helicity wavenumber spectrum. This coherence is also examined for two LES models, a traditional purely dissipative eddy viscosity model and a modern method (LANS$-\\alpha$) that respects the nonlinear transport properties of fluids. Both LES models properly represent the spectral energy and energy dissipation associated with this vorticity surge event. However, only the model that preserves nonlinear fluid transport properties reproduces the helical properties, including Beltrami-like vortex tubes.

Darryl D. Holm; Robert M. Kerr

2001-10-19T23:59:59.000Z

177

Coherence Holography and Spatial Frequency Comb for 3-D Coherence Imaging and Coherence Vortex Generation  

Science Journals Connector (OSTI)

The principle and the applications of a recently proposed unconventional holography technique, coherence holography, applied for coherence vortex generation, and a related technique...

Takeda, Mitsuo; Wang, Wei; Duan, Zhihui; Miyamoto, Yoko; Rosen, Joseph

178

Vortex shedding from square plates near a ground plane: an experimental study.  

E-Print Network (OSTI)

??Vortex shedding frequencies were obtained experimentally for square plates near a ground plane in the Texas Tech wind tunnel. These frequencies, in the form of… (more)

Matty, Rosemary Ricohermoso

1979-01-01T23:59:59.000Z

179

Rotational Doppler-effect due to selective excitation of vector-vortex field in optical fiber  

Science Journals Connector (OSTI)

Experimental demonstration of rotational Doppler-effect due to direct and simultaneous excitation of orthogonal elliptically-polarized fundamental and vortex modes in a two-mode...

Inavalli, V V G Krishna; Viswanathan, Nirmal K

2011-01-01T23:59:59.000Z

180

Oxygen to the core  

NLE Websites -- All DOE Office Websites (Extended Search)

1-01 1-01 For immediate release: 01/10/2013 | NR-13-01-01 Oxygen to the core Anne M Stark, LLNL, (925) 422-9799, stark8@llnl.gov Printer-friendly An artist's conception of Earth's inner and outer core. LIVERMORE, Calif. -- An international collaboration including researchers from Lawrence Livermore National Laboratory has discovered that the Earth's core formed under more oxidizing conditions than previously proposed. Through a series of laser-heated diamond anvil cell experiments at high pressure (350,000 to 700,000 atmospheres of pressure) and temperatures (5,120 to 7,460 degrees Fahrenheit), the team demonstrated that the depletion of siderophile (also known as "iron loving") elements can be produced by core formation under more oxidizing conditions than earlier

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Core assembly storage structure  

DOE Patents (OSTI)

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.

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

1988-01-01T23:59:59.000Z

182

Effects of pressure gradient on global Alfvén eigenmodes in reversed field pinch  

SciTech Connect

The effects of pressure gradient on the existence of global Alfvén eigenmodes (GAE) in Reversed Field Pinch are studied by numerical calculation. It is found that GAEs near the plasma core can exist when pressure gradient is sufficiently large. The calculated mode frequency and structure are consistent with the experimental results in the Madison Symmetric Torus.

Cai, Huishan, E-mail: hscai@mail.ustc.edu.cn [CAS Key Laboratory of Geospace Environment, Department of Modern Physics, University of Science and Technology of China, Hefei 230026 (China)] [CAS Key Laboratory of Geospace Environment, Department of Modern Physics, University of Science and Technology of China, Hefei 230026 (China); Fu, Guoyong, E-mail: fu@pppl.gov [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)] [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Lin, Liang; Ding, Weixing; Brower, D. L. [Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095 (United States)] [Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095 (United States); Liu, D. Y. [Physics Department, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)] [Physics Department, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Hu, Y. J. [Institute of Plasma Physics, CAS (China)] [Institute of Plasma Physics, CAS (China)

2014-02-15T23:59:59.000Z

183

Plasma engineering design of a compact reversed-field pinch reactor (CRFPR)  

SciTech Connect

The rationale for and the characteristics of the high-power-density Compact Reversed-Field Pinch Reactor (CRFPR) are discussed. Particular emphasis is given to key plasma engineering aspects of the conceptual design, including plasma operations, current drive, and impurity/ash control by means of pumped limiters or magnetic divertors. A brief description of the Fusion-Power-Core integration is given.

Bathke, C.G.; Embrechts, M.J.; Hagenson, R.L.; Krakowski, R.A.; Miller, R.L.

1983-01-01T23:59:59.000Z

184

Reverse engineering the human brain  

Science Journals Connector (OSTI)

...Thompson Reverse engineering the human brain Vincent Walsh Department of Experimental...can be used to temporarily prevent the brain from carrying out some of its normal functions...outline some of the advances in understanding brain function made by using TMS, and, in particular...

2000-01-01T23:59:59.000Z

185

Cosmological Significance of Time Reversal  

Science Journals Connector (OSTI)

... reversal at nearly the same time, that time being coincident with the occurrence of the Schwarzschild singularity, that is, the point at which the limiting radius, R = GM/ ... increases it would seem that a phenomenon not dissimilar to the spherical gravitational collapse of Schwarzschild will inevitably commence. This phenomenon depends on the relative velocity, and thus the position ...

KARY MULLIS

1968-05-18T23:59:59.000Z

186

Transport and equilibrium in field-reversed mirrors  

SciTech Connect

Two plasma models relevant to compact torus research have been developed to study transport and equilibrium in field reversed mirrors. In the first model for small Larmor radius and large collision frequency, the plasma is described as an adiabatic hydromagnetic fluid. In the second model for large Larmor radius and small collision frequency, a kinetic theory description has been developed. Various aspects of the two models have been studied in five computer codes ADB, AV, NEO, OHK, RES. The ADB code computes two dimensional equilibrium and one dimensional transport in a flux coordinate. The AV code calculates orbit average integrals in a harmonic oscillator potential. The NEO code follows particle trajectories in a Hill's vortex magnetic field to study stochasticity, invariants of the motion, and orbit average formulas. The OHK code displays analytic psi(r), B/sub Z/(r), phi(r), E/sub r/(r) formulas developed for the kinetic theory description. The RES code calculates resonance curves to consider overlap regions relevant to stochastic orbit behavior.

Boyd, J.K.

1982-09-01T23:59:59.000Z

187

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

E-Print Network (OSTI)

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 ...

Dahl, Jason (Jason Michael)

2008-01-01T23:59:59.000Z

188

AO Core Competency Worksheet  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

AO Core Competency Worksheet AO Core Competency Worksheet 1 DOE CYBER SECURITY EBK: CORE COMPETENCY TRAINING REQUIREMENTS Key Cyber Security Role: Authorizing Official (AO) Role Definition: The AO is the Senior DOE Management Federal official with the authority to formally assume responsibility and be held fully accountable for operating an information system at an acceptable level of risk. Competency Area: Incident Management Functional Requirement: Manage Competency Definition: Refers to the knowledge and understanding of the processes and procedures required to prevent, detect, investigate, contain, eradicate, and recover from incidents that impact the organizational mission as directed by the DOE Cyber Incident Response Capability (CIRC). Behavioral Outcome: Individuals fulfilling the role of AO will have a working knowledge of policies

189

Earth's Core Hottest Layer  

NLE Websites -- All DOE Office Websites (Extended Search)

Earth's Core Hottest Layer Earth's Core Hottest Layer Name: Alfred Status: Grade: 6-8 Location: FL Country: USA Date: Spring 2011 Question: Why is the inner core the hottest layer? How is that possible? Replies: There are two factors causing the center of the Earth hotter than various layers of the Earth's. First, the more dense is the layer. The denser layer, the hotter it will be. In addition, the source of the heating is due to heat produced by nuclear decay. These substances tend to be more dense than lower dense substances. So the source of heat (temperature) is higher, the greater will be the temperature. Having said all that, the reasons are rather more complicated in the "real" Earth. If the inner layers were less dense they would rise (bubble) to the "surface" leaving the inner layers more dense and thus hotter layers.

190

2000 BTS Core Databook  

Buildings Energy Data Book (EERE)

0 BTS CORE DATABOOK 0 BTS CORE DATABOOK 2000 BTS CORE DATABOOK OFFICE OF ENERGY EFFICIENCY AND RENEWABLE ENERGY * U.S. DEPARTMENT OF ENERGY This version is dated: August 7, 2000 DISCLAIMER This document was designed for the internal use of the United States Department of Energy. This document was also designed to be occasionally updated and, therefore, this copy may not reflect the most current version. This document was prepared as account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that

191

van Hove singularities and vortex motion in superconductors B. I. Ivlev,1,2  

E-Print Network (OSTI)

´ 78000, Mexico Received 16 February 2001; published 18 June 2001 When vortices move in a type by an electric current, any peculiarity of the vortex radiation friction due to emission of acoustic waves vortices. When a vortex moves under the action of a transport electric current, an electric field

Kunchur, Milind N.

192

Nucleation-controlled vortex entry in a square-columnar Josephson-junction array  

SciTech Connect

The initial magnetization curve of square-columnar Josephson-junction arrays is calculated from fundamental laws. It is found that the first vortex entry is controlled by vortex nucleation rather than surface depinning and it occurs at a field greater than that predicted by the traditional surface-barrier theory. {copyright} {ital 1997} {ital The American Physical Society}

Chen, D.; Moreno, J.J.; Hernando, A. [Instituto de Magnetismo Aplicado, RENFE-UCM-CSIC, 28230 Las Rozas, Madrid (Spain)] [Instituto de Magnetismo Aplicado, RENFE-UCM-CSIC, 28230 Las Rozas, Madrid (Spain)

1997-08-01T23:59:59.000Z

193

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

E-Print Network (OSTI)

Modeling bubble-vortex interactions Modeling and simulation of multiple bubble entrainment, OR 97331. (Dated: 5 November 2010) 1 #12;Modeling bubble-vortex interactions Simulations of bubble direct numerical simulation whereas motion of subgrid bubbles is modeled using Lagrangian track- ing

Apte, Sourabh V.

194

Generation and Propagation of InertiaGravity Waves from Vortex Dipoles and Jets SHUGUANG WANG*  

E-Print Network (OSTI)

Generation and Propagation of Inertia­Gravity Waves from Vortex Dipoles and Jets SHUGUANG WANG) ABSTRACT This study investigates gravity wave generation and propagation from jets within idealized vortex, geostrophic adjust- ment, and spontaneous generation (Fritts and Alexander 2003, and references therein

195

Hopper Multi-Core FAQ  

NLE Websites -- All DOE Office Websites (Extended Search)

Hopper Multi-Core FAQ Hopper Multi-Core FAQ Hopper Multi-Core FAQ Q. How is Hopper Different than Franklin? A. The new Hopper Phase-II system will have 24 cores per node. Franklin had only four. Q. What else is different? A. There is less memory per core. Hopper has 1.3 GB / core rather than 2.0 GB / core on Franklin. A code using MPI on Hopper may be more likely to exhaust available memory, causing an error. Additionally, Hopper's memory hierarchy is "deeper" and more non-uniform than Franklin's and this can have a big impact on performance in certain cases. Hopper's 24 cores per node are implemented on two sockets, each containing two six-core dies (see the image below). Each of the six-core dies has direct access to one-quarter of the node's total memory. Thus,

196

TMI-2 core examination  

SciTech Connect

The examination of the damaged core at the Three Mile Island Unit 2 (TMI-2) reactor is structured to address the following safety issues: fission product release, transport, and deposition; core coolability; containment integrity; and recriticality during severe accidents; as well as zircaloy cladding ballooning and oxidation during so-called design basis accidents. The numbers of TMI-2 components or samples to be examined, the priority of each examination, the safety issue addressed by each examination, the principal examination techniques to be employed, and the data to be obtained and the principal uses of the data are discussed in this paper.

Hobbins, R.R.; MacDonald, P.E.; Owen, D.E.

1983-01-01T23:59:59.000Z

197

Stripe Domains and First-Order Phase Transition in the Vortex Matter of Anisotropic High-Temperature Superconductors  

E-Print Network (OSTI)

Stripe Domains and First-Order Phase Transition in the Vortex Matter of Anisotropic High-Temperature temperature superconductor and reveal a sharp transition in the state of this phase resulting in regular that can subsequently melt at high temperatures to a vortex liquid, a pinned vortex glassy state that can

Alexei, Koshelev

198

Effect of time-dependent piston velocity program on vortex ring formation in a piston/cylinder arrangement  

E-Print Network (OSTI)

Effect of time-dependent piston velocity program on vortex ring formation in a piston An analytical model describing laminar vortex ring formation in a nozzle flow generator piston/ cylinder.1063/1.2188918 I. INTRODUCTION Vortex rings are usually generated in the laboratory by the motion of a piston

Dabiri, John O.

199

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

E-Print Network (OSTI)

, and parts of the initial vortical tubes can be left behind as vortex threads, which then undergo successivearXiv:1206.2498v2[cond-mat.other]19Nov2012 Quantum vortex reconnections S. Zuccher,1 M. Caliari,1 A with time before and after the vor- tex reconnection. We also compute vortex reconnections using the Biot

Caliari, Marco

200

The role of boundary conditions in a simple model of incipient vortex breakdown F. Gallaire and J.-M. Chomaz  

E-Print Network (OSTI)

. In the labora- tory, it is preferentially studied in vortex tubes, where it is seen in many cases to give riseThe role of boundary conditions in a simple model of incipient vortex breakdown F. Gallaire and J of a hairpin vortex in a shear-thinning fluid governed by a power-law model Phys. Fluids 25, 101703 (2013); 10

Boyer, Edmond

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Concentrating Fruit Juices by Reverse Osmosis  

Science Journals Connector (OSTI)

The difference between reverse osmosis and ultrafiltration lies principally in the retention ... able to retain protein-sized molecules, whereas reverse osmosis membranes retain lower molecular weight solutes suc...

R. L. Merson; G. Paredes; D. B. Hosaka

1980-01-01T23:59:59.000Z

202

Quantum dynamics of a vortex in a Josephson junction  

SciTech Connect

We investigate the tunneling character of vortex in an asymmetrical potential well with a finite barrier by using the periodic instanton method. We obtain the total decay rate which is valid for the entire range of temperature and show how it reduces to the appropriate results for the classical thermal activation at high temperatures, the thermally assisted tunneling at intermediate temperatures, and the pure quantum tunneling at low temperature. We can even give the exact definition of the 'crossover' temperature and find experimental data to support our theoretical analysis.

Li Hong; Liu Wuming [Joint Laboratory of Advanced Technology in Measurements, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080 (China); Shen Shunqing [Department of Physics, University of Hong Kong, Pokfulam Road, Hong Kong (China); Liang Jiuqing [Institute of Theoretical Physics, Shanxi University, Taiyuan, Shanxi 030006 (China)

2005-07-01T23:59:59.000Z

203

Collective Effects in Vortex Movements in Complex Plasmas  

Science Journals Connector (OSTI)

We study the onset and characteristics of vortices in complex (dusty) plasmas using two-dimensional simulations in a setup modeled after the PK-3 Plus laboratory. A small number of microparticles initially self-arranges in a monolayer around the void. As additional particles are introduced, an extended system of vortices develops due to a nonzero curl of the plasma forces. We demonstrate a shear-thinning effect in the vortices. Velocity structure functions and the energy and enstrophy spectra show that vortex flow turbulence is present that is in essence of the “classical” Kolmogorov type.

Mierk Schwabe, Sergey Zhdanov, Christoph Räth, David B. Graves, Hubertus M. Thomas, and Gregor E. Morfill

2014-03-19T23:59:59.000Z

204

Spontaneous vortex phase and pinning in ferromagnetic-superconducting systems  

E-Print Network (OSTI)

of epsilon10 as a function of rho0lambda for the case when n = 1, lambdaxi = 10,R1 = lambda,R2 = 2lambda and deltam = 10. . . . . . . . . . . . . . . 31 ix FIGURE Page 12 A superconducting thin film pierced by a ferromagnetic nano rod of radius R, length L... circle of radius rho0 that depends on the radii and magnetization per unit area of the annulus, and on the SC pene- tration depth lambda. In section five I focus on pinning and spontaneous vortex creation by a ferromagnetic rod which penetrates...

Kayali, Mohammad Amin

2004-09-30T23:59:59.000Z

205

Reversals  

Science Journals Connector (OSTI)

By the fall of 1996, a few months before Jim Hall made the case against the Boeing 737 in his long letter to the...

Gerry Byrne

2002-01-01T23:59:59.000Z

206

Interaction of Josephson Junction and Distant Vortex in Narrow Thin-Film Superconducting Strips  

SciTech Connect

The phase difference between the banks of an edge-type planar Josephson junction crossing the narrow thin-film strip depends on wether or not vortices are present in the junction banks. For a vortex close to the junction this effect has been seen by Golod, Rydh, and Krasnov [Phys. Rev. Lett. 104, 227003 (2010)], who showed that the vortex may turn the junction into ? type. It is shown here that even if the vortex is far away from the junction, it still changes the 0 junction to a ? junction when situated close to the strip edges. Within the approximation used, the effect is independent of the vortex-junction separation, a manifestation of the topology of the vortex phase which extends to macroscopic distances of superconducting coherence.

Kogan, V. G. [Ames Laboratory; Mints, R. G. [Tel Aviv University

2014-01-31T23:59:59.000Z

207

Reverse engineering of integrated circuits  

DOE Patents (OSTI)

Software and a method therein to analyze circuits. The software comprises several tools, each of which perform particular functions in the Reverse Engineering process. The analyst, through a standard interface, directs each tool to the portion of the task to which it is most well suited, rendering previously intractable problems solvable. The tools are generally used iteratively to produce a successively more abstract picture of a circuit, about which incomplete a priori knowledge exists.

Chisholm, Gregory H. (Shorewood, IL); Eckmann, Steven T. (Colorado Springs, CO); Lain, Christopher M. (Pittsburgh, PA); Veroff, Robert L. (Albuquerque, NM)

2003-01-01T23:59:59.000Z

208

Reversible Seeding in Storage Rings  

SciTech Connect

We propose to generate steady-state microbunching in a storage ring with a reversible seeding scheme. High gain harmonic generation (HGHG) and echo-enabled harmonic generation (EEHG) are two promising methods for microbunching linac electron beams. Because both schemes increase the energy spread of the seeded beam, they cannot drive a coherent radiator turn-by-turn in a storage ring. However, reversing the seeding process following the radiator minimizes the impact on the electron beam and may allow coherent radiation at or near the storage ring repetition rate. In this paper we describe the general idea and outline a proof-of-principle experiment. Electron storage rings can drive high average power light sources, and free-electron lasers (FELs) are now producing coherent light sources of unprecedented peak brightness While there is active research towards high repetition rate FELs (for example, using energy recovery linacs), at present there are still no convenient accelerator-based sources of high repetition rate, coherent radiation. As an alternative avenue, we recently proposed to establish steady-state microbunching (SSMB) in a storage ring. By maintaining steady-state coherent microbunching at one point in the storage ring, the beam generates coherent radiation at or close to the repetition rate of the storage ring. In this paper, we propose a method of generating a microbunched beam in a storage ring by using reversible versions of linac seeding schemes.

Ratner, Daniel; Chao, Alex; /SLAC

2011-12-14T23:59:59.000Z

209

SECA Core Technology Program  

NLE Websites -- All DOE Office Websites (Extended Search)

January 27 - January 27 - 28, 2005 Workshop Peer Review Rating Results Summary Donald Collins SECA Core January 2005 Workshop Peer Review Summary - DWC,PM-30,3-10-05 2 of 21 Review Process Summary * Core Technology Project Presentations - Project Objectives & Results - Non-proprietary Information - Industry, National Lab & University Participation * Verbal & Written Constructive Comments - Written Comments on Peer Review Forms - Industry Verbal Feedback at Workshop * Core Participant Review & Reply to Comments - Reply to Comment Issues * DOE NETL Redirect Projects as Needed M a t e r i a l s C o n t r o l s & D i a g n o s t i c s P o w e r E le c t r o n ic s F u e l P r o c e s s i n g Manufacturing M o d e li n g & S im u la ti o n SECA Core January 2005 Workshop Peer Review Summary - DWC,PM-30,3-10-05 3 of 21 Peer Review Questions

210

SECA Core Technology Program  

NLE Websites -- All DOE Office Websites (Extended Search)

May 12 - May 12 - 13, 2004 Workshop Peer Review Rating Results Summary Donald Collins SECA Core May 2004 Workshop Peer Review Summary - DWC,PM-30,5-21-04 2 of 16 Review Process Summary * Core Technology Project Presentations - Project Objectives & Results - Non-proprietary Information - Industry, National Lab & University Participation * Verbal & Written Constructive Comments - Written Comments on Peer Review Forms - Industry Verbal Feedback at Workshop * Core Participant Review & Reply to Comments - Reply to Comment Issues * DOE NETL Redirect Projects as Needed M a t e r i a l s C o n t r o l s & D i a g n o s t i c s P o w e r E le c t r o n ic s F u e l P r o c e s s i n g Manufacturing M o d e li n g & S im u la ti o n SECA Core May 2004 Workshop Peer Review Summary - DWC,PM-30,5-21-04 3 of 16 Peer Review Questions

211

Plan ?: core or cusp?  

Science Journals Connector (OSTI)

......research-article Article Plan beta: core or cusp? Thomas...Breddels (2013) for a detailed review of the more sophisticated numerical...is available for each star (standard technique). Large data sets...velocity space, we use the standard definition, for the velocity......

Thomas D. Richardson; Douglas Spolyar; Matthew D. Lehnert

2014-01-01T23:59:59.000Z

212

Core competence (knowledge) (skill)  

E-Print Network (OSTI)

Core competence 8 5~8 2 3 4 5 6 7 8 PPS003 Ver. 1.1 2011/03/07 #12; 2 (knowledge) (skill) (attitude) Set of skill, knowledge or attitude which should be learned or acquired by each, 2000) (knowledge) (skill) (attitude) Set of skill, knowledge or attitude which should be learned

Wu, Yih-Min

213

Dynamics of core accretion  

Science Journals Connector (OSTI)

......formation, the accretor is of course a rocky planetary core, on to which gas accretion...both cases, the distributions are nearly flat at large distances (i.e.-R H...the evolution of the simulation, using a safety factor of J- 4. Nevertheless, at time......

Andrew F. Nelson; Maximilian Ruffert

2013-01-01T23:59:59.000Z

214

Dynamics of core accretion  

Science Journals Connector (OSTI)

......the accretor is of course a rocky planetary core, on to which...the distributions are nearly flat at large distances (i.e...numerically induced collapse through violation of the Jeans criterion (Truelove...of the simulation, using a safety factor of J- 4. Nevertheless......

Andrew F. Nelson; Maximilian Ruffert

2013-01-01T23:59:59.000Z

215

The Carlson-Simpson Lemma in Reverse Mathematics  

E-Print Network (OSTI)

6.3 Reverse Mathematicswords . . . . . 1.4 Reverse Mathematics diagrams Miller-1.1 Reverse Mathematics . . . . . . 1.2 The Dual Ramsey

Erhard, Julia Christina

2013-01-01T23:59:59.000Z

216

Reversible Fuel Cells Workshop Summary Report | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Reversible Fuel Cells Workshop Summary Report Reversible Fuel Cells Workshop Summary Report Summary and presentations from the NREL Reversible Fuel Cells Workshop held April 19,...

217

Core Holes | Open Energy Information  

Open Energy Info (EERE)

Core Holes Core Holes Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Core Holes Details Activities (8) Areas (7) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Drilling Techniques Exploration Sub Group: Exploration Drilling Parent Exploration Technique: Exploration Drilling Information Provided by Technique Lithology: Core holes are drilled to identify lithology and mineralization Stratigraphic/Structural: Retrieved samples can be used to identify fracture networks or faults Hydrological: Thermal: Thermal conductivity measurements can be done on retrieved samples. Dictionary.png Core Holes: A core hole is a well that is drilled using a hallow drill bit coated with synthetic diamonds for the purposes of extracting whole rock samples from

218

Random center vortex lines in continuous 3D space-time  

E-Print Network (OSTI)

We present a model of center vortices, represented by closed random lines in continuous 2+1- dimensional space- time. These random lines are modeled as being piece-wise linear and an ensemble is generated by Monte Carlo methods. The physical space in which the vortex lines are defined is a cuboid with periodic boundary conditions. Besides moving, growing and shrinking of the vortex configuration, also reconnections are allowed. Our ensemble therefore contains not a fixed, but a variable number of closed vortex lines. This is expected to be important for realizing the deconfining phase transition. Using the model, we study both vortex percolation and the potential V (R) between quark and anti-quark as a function of distance R at different vortex densities, vortex segment lengths, reconnection conditions and at different temperatures. We have found three deconfinement phase transitions, as a function of density, as a function of vortex segment length, and as a function of temperature. The model reproduces the qualitative features of confinement physics seen in SU(2) Yang-Mills theory.

Roman Höllwieser; Derar Altarawneh; Michael Engelhardt

2014-11-26T23:59:59.000Z

219

Core Measure Results  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Core Measure Core Measure Results FY 07 Results FY 08 Results FY 09 Results FY 10 Target FY 10 Customer Perspective: Customer Satisfaction: -Timeliness NM 81 NM NM NM -Quality NM 90 NM NM NM Effective Service Partnership: -Extent of Customer Satisfaction with the responsiveness, etc. NM 87 NM NM NM Internal Business Perspective: Acquisition Excellence: -Extent to which internal quality control systems are effective 86 87 84 87 88 Most Effective Use of Contracting Approaches to Maximize Efficiency and Cost Effectiveness: Use of Electronic Commerce: - % of delivery & purchase orders issued electronically as a % of total simplified actions 70 72 89 99 100 - % of new competitive transactions > $100K conducted through EC 70 72 91 100 95 Performance Based Service Contracts: - PBSCs awarded as a % of eligible new

220

Banded electromagnetic stator core  

DOE Patents (OSTI)

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.

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

1996-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Banded electromagnetic stator core  

DOE Patents (OSTI)

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.

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

1994-01-01T23:59:59.000Z

222

Variable depth core sampler  

DOE Patents (OSTI)

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.

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

1996-01-01T23:59:59.000Z

223

Electromagnetic pump stator core  

DOE Patents (OSTI)

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.

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

1995-01-17T23:59:59.000Z

224

Banded electromagnetic stator core  

DOE Patents (OSTI)

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

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

1996-06-11T23:59:59.000Z

225

Banded electromagnetic stator core  

DOE Patents (OSTI)

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.

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

1994-04-05T23:59:59.000Z

226

Variable depth core sampler  

DOE Patents (OSTI)

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.

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

1996-02-20T23:59:59.000Z

227

Core Analysis | Open Energy Information  

Open Energy Info (EERE)

Core Analysis Core Analysis Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Core Analysis Details Activities (41) Areas (28) Regions (2) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Rock Lab Analysis Parent Exploration Technique: Rock Lab Analysis Information Provided by Technique Lithology: Core analysis is done to define lithology. Stratigraphic/Structural: Core analysis can locate faults or fracture networks. Oriented core can give additional important information on anisotropy. Hydrological: Thermal: Thermal conductivity can be measured from core samples. Cost Information Low-End Estimate (USD): 2,000.00200,000 centUSD 2 kUSD 0.002 MUSD 2.0e-6 TUSD / 30 foot core Median Estimate (USD): 10,000.001,000,000 centUSD

228

Vortex and gap generation in gauge models of graphene  

E-Print Network (OSTI)

Effective quantum field theoretical continuum models for graphene are investigated. The models include a complex scalar field and a vector gauge field. Different gauge theories are considered and their gap patterns for the scalar, vector, and fermion excitations are investigated. Different gauge groups lead to different relations between the gaps, which can be used to experimentally distinguish the gauge theories. In this class of models the fermionic gap is a dynamic quantity. The finite-energy vortex solutions of the gauge models have the flux of the "magnetic field" quantized, making the Bohm-Aharonov effect active even when external electromagnetic fields are absent. The flux comes proportional to the scalar field angular momentum quantum number. The zero modes of the Dirac equation show that the gauge models considered here are compatible with fractionalization.

O. Oliveira; C. E. Cordeiro; A. Delfino; W. de Paula; T. Frederico

2010-12-21T23:59:59.000Z

229

Reverse Computation for Rollback-based Fault Tolerance in Large Parallel Systems  

SciTech Connect

Reverse computation is presented here as an important future direction in addressing the challenge of fault tolerant execution on very large cluster platforms for parallel computing. As the scale of parallel jobs increases, traditional checkpointing approaches suffer scalability problems ranging from computational slowdowns to high congestion at the persistent stores for checkpoints. Reverse computation can overcome such problems and is also better suited for parallel computing on newer architectures with smaller, cheaper or energy-efficient memories and file systems. Initial evidence for the feasibility of reverse computation in large systems is presented with detailed performance data from a particle simulation scaling to 65,536 processor cores and 950 accelerators (GPUs). Reverse computation is observed to deliver very large gains relative to checkpointing schemes when nodes rely on their host processors/memory to tolerate faults at their accelerators. A comparison between reverse computation and checkpointing with measurements such as cache miss ratios, TLB misses and memory usage indicates that reverse computation is hard to ignore as a future alternative to be pursued in emerging architectures.

Perumalla, Kalyan S [ORNL; Park, Alfred J [ORNL

2013-01-01T23:59:59.000Z

230

An overview of time?reversal acoustics  

Science Journals Connector (OSTI)

Time?reversal invariance is a very powerful concept in physics. In the field of acoustics where time reversal invariance occurs time?reversal experiments may be achieved simply with arrays of transmit?receive transducers allowing an incident wave field to be sampled recorded time?reversed and re?emitted. Time reversal mirrors (TRMs) may be used to study random media and chaotic reverberating structures. Common to these complex media is a remarkable robustness exemplified by observations that the more complex the medium between the probe source and the TRM the sharper the focus. TRMs open the way to new signal processings that interest imaging detection telecommunications and therapy. Time reversal mirrors have plenty of applications including ultrasonic therapy and medical imaging non destructive testing telecommunications underwater acoustics seismology sound control home automation. An overview of these fields will be presented.

Mathias Fink

2008-01-01T23:59:59.000Z

231

Watermelon-like iron nanoparticles: Cr doping effect on magnetism and magnetization interaction reversal  

SciTech Connect

Chromium (Cr) forms a solid solution with iron (Fe) lattice when doped in core-shell iron -iron oxide nanocluster (NC) and shows a mixed phase of sigma (?) FeCr and bcc Fe. The Cr dopant affects heavily the magnetization and magnetic reversal process, and causes the hysteresis loop to shrink near the zero field axis. Dramatic transformation happens from dipolar interaction (0 at. % Cr) to strong exchange interaction (8 at. % of Cr) is confirmed from the Henkel plot and delta M plot, and is explained by a water-melon model of core-shell NC system.

Kaur, Maninder; Dai, Qilin; Bowden, Mark E.; Engelhard, Mark H.; Wu, Yaqiao; Tang, Jinke; Qiang, You

2013-06-26T23:59:59.000Z

232

Core Competency Worksheets for Significant Cybersecurity Roles...  

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

Core Competency Worksheets for Significant Cybersecurity Roles Core Competency Worksheets for Significant Cybersecurity Roles The OCIO has developed core competency worksheets for...

233

2001 BTS Core Databook  

Buildings Energy Data Book (EERE)

1 BTS CORE 1 BTS CORE DATABOOK OFFICE OF ENERGY EFFICIENCY AND RENEWABLE ENERGY U.S. DEPARTMENT OF ENERGY This version is dated: November 30, 2001 REVISED data tables on the web site that have been changed since November 30, 2001 include tables: 5.6.7 5.6.8 5.6.9 5.10.8 5.10.9 5.10.10 5.10.11 5.10.12 5.10.13 5.10.14 5.10.15 5.10.16 5.10.17 5.10.18 NEW data tables on the web site that have been added since July 13, 2001 include tables: 5.6.14 5.9.7 5.9.8 5.9.9 REVISED data tables on the web site that have been changed since July 13, 2001 include tables: 4.1.1 4.1.2 4.1.4 4.1.5 4.2.1 4.2.2 4.2.3 4.2.4 4.2.5 4.2.9 4.3.1 4.3.2 4.3.3 4.3.4 4.5.1 4.5.2 4.5.3 5.1.2 5.3.1 5.8.1 5.10.1 6.2.4 7.1.8 7.3.3 These tables are not included in this version of the 2001 BTS Core Databook. DISCLAIMER DISCLAIMER DISCLAIMER DISCLAIMER

234

Core-tube data logger  

SciTech Connect

Wireline core drilling, increasingly used for geothermal exploration, employs a core-tube to capture a rock core sample during drilling. Three types of core-tube data loggers (CTDL) have been built and tested to date by Sandia national Laboratories. They are: (1) temperature-only logger, (2) temperature/inclinometer logger and (3) heat-shielded temperature/inclinometer logger. All were tested during core drilling operations using standard wireline diamond core drilling equipment. While these tools are designed for core-tube deployment, the tool lends itself to be adapted to other drilling modes and equipment. Topics covered in this paper include: (1) description on how the CTDLs are implemented, (2) the components of the system, (3) the type of data one can expect from this type of tool, (4) lessons learned, (5) comparison to its counterpart and (6) future work.

Henfling, J.A.; Normann, R.A.; Knudsen, S.; Drumheller, D.

1997-01-01T23:59:59.000Z

235

Boundary-Layer Effects in Reverse Osmosis  

Science Journals Connector (OSTI)

Boundary-Layer Effects in Reverse Osmosis ... In FO, water is extracted from a feed solution using the high osmotic pressure of a hypertonic solution that flows on ... ...

Ulrich Merten; H. K. Lonsdale; R. L. Riley

1964-01-01T23:59:59.000Z

236

CFD Numerical Simulation of Vortex-Induced Vibration of a Stay Cable under a Wind Profile  

Science Journals Connector (OSTI)

VIV (Vortex-induced vibration) of a stay cable subjected to a wind profile is numerically simulated through combining CFD ... numerical model. Under a profile of mean wind speed, unsteady aerodynamic lift coeffic...

Wenli Chen; Hui Li

2009-01-01T23:59:59.000Z

237

Optimal Excitation of Asymmetric Perturbations on an Axisymmetric Barotropic Vortex: A linear Singular Value Analysis  

Science Journals Connector (OSTI)

Singular vectors on a barotropic circular vortex consisting of three regions of piecewise-constant vorticity are investigated under the L2-norm to reveal the shape and growth rate of possible perturbations that may contribute to the formation of ...

Toshihisa Itano

238

Dynamical mass of a quantum vortex in a Josephson junction array  

SciTech Connect

The real-time response to a small external perturbation of a vortex in a quantum Josephson junction array, with long-range Coulomb interaction between Cooper pairs, is analyzed. While the static damping is zero for vortex velocities below some threshold value v{sub th} (which implies the possibility of ballistic motion), a dynamical friction due to the coupling to the plasma oscillations is always present for frequencies higher than a given threshold {omega}{sub th}. The latter approaches zero when the velocity increases to v{sub th}. However, radiative dissipation of the vortex affects the threshold for ballistic motion. We discuss the conditions under which a mass can be defined for the vortex as a quantum particle. {copyright} {ital 1997} {ital The American Physical Society}

Eckern, U. [Institut fuer Physik, Universitaet Augsburg, D-86135 Augsburg (Germany)] [Institut fuer Physik, Universitaet Augsburg, D-86135 Augsburg (Germany); Luciano, G.; Tagliacozzo, A. [Dipartimento di Scienze Fisiche, Universita di Napoli, Mostra dOltremare Pad. 19, I-80125 Napoli (Italy)] [Dipartimento di Scienze Fisiche, Universita di Napoli, Mostra dOltremare Pad. 19, I-80125 Napoli (Italy); [Istituto Nazionale di Fisica della Materia (INFM), I-16152 Genova (Italy)

1997-12-01T23:59:59.000Z

239

E-Print Network 3.0 - axially-symmetric cyclonic vortex Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

> >> 1 1 APRIL 2002 1213W A N G 2002 American Meteorological Society Summary: and wind fields of the vortex Rossby waves are quasi-balanced, with confluent cyclonic (divergent... ,...

240

Ultraviolet vortex generation using periodically bonded ?-BaB2O4 device  

Science Journals Connector (OSTI)

This paper describes the first demonstration of ultraviolet (266nm) vortex generation using the combination of a frequency-doubled nanosecond green laser, a spiral phase plate, and a...

Sasaki, Yuta; Koyama, Mio; Miyamoto, Katsuhiko; Ariga, Yoshimi; Onda, Tomomi; Shoji, Ichiro; Omatsu, Takashige

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Vortex-Induced Vibration of a slender horizontal cylinder in currents and waves  

E-Print Network (OSTI)

Vortex-Induced Vibration (VIV) is a concern when dealing with slender, flexible structural members of deepwater platforms. While much is known about the characteristics of VIV in uniform and sheared current flows, very little is known about...

Chitwood, James Scott

2012-06-07T23:59:59.000Z

242

Application of fiber Bragg grating based strain sensor in pipeline vortex-induced vibration measurement  

Science Journals Connector (OSTI)

The vortex-induced vibrations (VIV) is an important topic of ... of different methods have been applied to the measurement of VIV, especially for the elongated, ... in stainless steel tubes were applied to the measurement

Liang Ren; ZiGuang Jia; Michael Siu Chun Ho…

2014-09-01T23:59:59.000Z

243

The Roles of Vortex Rossby Waves in Hurricane Secondary Eyewall Formation  

Science Journals Connector (OSTI)

A high-resolution, full-physics model initiated with an idealized tropical cyclone–like vortex is used to simulate and investigate the secondary eyewall formation. The beta skirt axisymmetrization (BSA) hypothesis previously proposed is examined ...

Xin Qiu; Zhe-Min Tan; Qingnong Xiao

2010-06-01T23:59:59.000Z

244

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

E-Print Network (OSTI)

Coherent vortices and their properties were studied in two- and three-layer quasi-geostrophic beta-plane turbulence. Much research has discussed vortex characteristics in a number of applications, but no significant study of vortices in turbulent...

Fox, Amanda Katherine

2012-06-07T23:59:59.000Z

245

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

E-Print Network (OSTI)

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 ...

Farrell, David Emmanuel

2007-01-01T23:59:59.000Z

246

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

E-Print Network (OSTI)

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...

Nelson, Carter T.

2012-06-07T23:59:59.000Z

247

Steady-state and equilibrium vortex configurations, transitions, and evolution in a mesoscopic superconducting cylinder  

E-Print Network (OSTI)

that the system passes through nearly metastable intermediate configurations while seeking the final minimum-energy steady state consistent with the square symmetry of the sample. An efficient scheme to determine the equilibrium vortex configuration in a...

Kim, S.; Hu, Chia-Ren; Andrews, MJ.

2004-01-01T23:59:59.000Z

248

An adaptive mesh method for the simulation of Blade Vortex Interaction  

E-Print Network (OSTI)

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...

Kim, Kyu-Sup

2012-06-07T23:59:59.000Z

249

MEC E 638 VORTEX FLOWS Winter 2014 LARGE-SCALE STRUCTURES IN TURBULENCE PROF L. SIGURDSON  

E-Print Network (OSTI)

to find the characteristic vortex structures; to read the literature, nomenclature, terminology. TOPICS: Professor Lorenz Sigurdson, 5-1B Mech Eng Bldg, lorenz@ualberta.ca, http://websrv.mece.ualberta.ca/intranet

Flynn, Morris R.

250

Visualization of Intricate Flow Structures for Vortex Breakdown Analysis Xavier Tricoche  

E-Print Network (OSTI)

Hansen University of Utah Figure 1: Vortex breakdown bubble in numerical simulation of a cylindrical to study their impact on flight stability. Yet, to fully exploit the huge amount of information contained

Utah, University of

251

Annular Vortex Generation for Inertial Fusion Energy Beam-Line Protection  

SciTech Connect

The use of swirling annular vortex flow inside beam entrance tubes can protect beam-line structural materials in chambers for heavy-ion inertial fusion energy (IFE) applications. An annular wall jet, or vortex tube, is generated by injecting liquid tangent to the inner surface of a tube wall with both axially and azimuthally directed velocity components. A layer of liquid then lines the beam tube wall, which may improve the effectiveness of neutron shielding, and condenses and removes vaporized coolant that may enter the beam tubes. Vortex tubes have been constructed and tested with a thickness of three-tenths the pipe radius. Analysis of the flow is given, along with experimental examples of vortex tube fluid mechanics and an estimate of the layer thickness, based on simple mass conservation considerations.

Pemberton, Steven J.; Abbott, Ryan P.; Peterson, Per F. [University of California (United States)

2003-05-15T23:59:59.000Z

252

Ioniclike energy structure of neutral core-excited states in free Kr clusters  

Science Journals Connector (OSTI)

The development of electronic states in krypton clusters is investigated by high-resolution core-level electron spectroscopy. The energy ordering of bulk versus surface 3d?1np(n>5) core-excited states in neutral clusters is demonstrated to be reversed to the 3d?15p level situation. The cluster 3d?16p,7p states are proven to be at a lower energy than the corresponding atomic levels. These findings reveal the ioniclike energy structure of the neutral cluster core-excited levels. The phenomenon is explained by a spatial spread of the excited orbitals over the cluster lattice.

S. Peredkov; A. Kivimäki; S. L. Sorensen; J. Schulz; N. Mårtensson; G. Öhrwall; M. Lundwall; T. Rander; A. Lindblad; H. Bergersen; S. Svensson; O. Björneholm; M. Tchaplyguine

2005-08-11T23:59:59.000Z

253

Reversible Modification of CdSe-CdS/ZnS Quantum Dot Fluorescence by Surrounding Ca2+  

E-Print Network (OSTI)

Reversible Modification of CdSe-CdS/ZnS Quantum Dot Fluorescence by Surrounding Ca2+ Ions Li Li (3-MPA) coated CdSe-CdS/ZnS core-multishell QDs when free Ca2+ ions were added to and subsequently removed from the QD solution. It was found that QD fluorescence intensity was reduced when Ca2+ ions were

Haviland, David

254

High-frequency vortex dynamics and dissipation of high-temperature superconductors  

Science Journals Connector (OSTI)

The high-frequency vortex dynamics of high-temperature superconductors near the flux-line depinning threshold is investigated based on a thermally activated flux-flow (TAFF) model. Dissipation due to vortex motion driven by a microwave electromagnetic field is studied as a function of the frequency, temperature, dc magnetic field, and microwave power. The generalized TAFF model is also compared to the conventional flux-creep theory and is found qualitatively consistent.

N.-C. Yeh

1991-01-01T23:59:59.000Z

255

Effect of a surface boundary layer on an intensifying, downward-propagating vortex  

E-Print Network (OSTI)

EFFECT OF A SURFACE BOUNDARY LAYER ON AN INTENSIFYING, DOWNWARD-PROPAGATING VORTEX A Thesis by VINCENT TUNSTALL WOOD Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE May 1977 Major Subject: Meteorology EFFECT OF A SURFACE BOUNDARY LAYER ON AN INTENSIFYING, DOWNWARD-PROPAGATING VORTEX A Thesis by VINCENT TUNSTALL WOOD Approved as to style and content by: (Chairman of Committee) (Head of Department...

Wood, Vincent Tunstall

2012-06-07T23:59:59.000Z

256

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

E-Print Network (OSTI)

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.

Timothy D. Andersen; Chjan C. Lim

2006-11-19T23:59:59.000Z

257

ALSNews Vol. 274  

NLE Websites -- All DOE Office Websites (Extended Search)

fields as low as 1.5 millitesla (mT) to reverse the direction of a vortex core. The observed switching mechanism, which can be understood within the framework of micromagnetic...

258

Final report for the field-reversed configuration power plant critical-issue scoping study  

SciTech Connect

This report describes research in which a team from the Universities of Wisconsin, Washington, and Illinois performed a scoping study of critical issues for field-reversed configuration (FRC) power plants. The key tasks for this research were (1) systems analysis of deuterium-tritium (D-T) FRC fusion power plants, and (2) conceptual design of the blanket and shield module for an FRC fusion core.

Santarius, John F.; Mogahed, Elsayed A.; Emmert, Gilbert A.; Khater, Hesham Y.; Nguyen, Canh N.; Ryzhkov, Sergei V.; Stubna, Michael D.; Steinhauer, Loren C.; Miley, George H.

2001-03-01T23:59:59.000Z

259

Modelling vortex-induced fluid–structure interaction  

Science Journals Connector (OSTI)

...Atsavapranee, T Wei, and J McHugh2000The role of turbulent elongational stresses on deflocculation in paper sheet formation. TAPPI J. 83, 70 Sibetheros, I. A., Miskad, R. W., Ventre, A.-V. Lambrakos, K. F. 1994 Flow mapping of the reversing...

2008-01-01T23:59:59.000Z

260

Dynamic core length in saturated core fault current limiters  

Science Journals Connector (OSTI)

A saturated core fault current limiter (SCFCL) is a non-linear core-reactor where the core is saturated by an external superconducting DC bias source to achieve a low core permeability at nominal AC currents. Fault current levels in the AC coils de-saturate the core and transform it to a higher permeability state, hence limiting the fault current. In this work we describe the transition between saturated and de-saturated states in three SCFCL configurations. The 'effective core length', Leff, of the SCFCL, defined as the length of the de-saturated AC core limb, is introduced for exploring this transition as a function of the current, I, in the AC coil. Practically, Leff allows one to see the SCFCL as an inductor with a variable core length, allowing calculations of the impedance of the SCFCL over the whole range of operating currents. The Leff(I) curve is further used to calculate the dynamics of the demagnetization factor in a SCFCL. We show that the strong change in the magnetic induction of a SCFCL at high current is the result of both increasing the effective core length and decreasing the demagnetization factor. The method and results presented here serve as an important tool for comparing between various SCFCL concepts not only by comparing their impedance values at the extreme fault and nominal current conditions but also by providing an insight into the full de-saturation process.

Y Nikulshin; Y Wolfus; A Friedman; Y Yeshurun

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Nonidentified Kikuchi lines with reverse contrast  

SciTech Connect

Electron diffraction patterns of silicon in transmission with contrast reversal from bright to dark for an unidentified Kikuchi line along its length have been obtained. The contrast reversal of an unidentified line is explained within the elementary mechanism of Kikuchi pattern formation taking into account the Kikuchi electron double diffraction.

Karakhanyan, K. R., E-mail: kkarakhanyan@yandex.ru [Yerevan State University (Armenia)

2009-03-15T23:59:59.000Z

262

REVERSIBLE SOLID OXIDE CELLS Mogens Mogensen1  

E-Print Network (OSTI)

The reversibility of solid oxide fuel cells (SOFC), i.e. that they could also work in the solid oxide electrolyser1 REVERSIBLE SOLID OXIDE CELLS Mogens Mogensen1 , Søren Højgaard Jensen1,2 , Anne Hauch1,3 , Ib Chorkendorff2 and Torben Jacobsen3 1 Fuel Cell and Solid State Chemistry Department Risø National Laboratory

263

Numerical simulation of a viscous vortex ring interaction with a density interface  

SciTech Connect

When a vortex-dominated flow interacts with a sharp density interface, the dynamics are characterized by the interaction of baroclinically generated vorticity with the already existing vorticity field. This can be seen in many natural and technology settings; examples are the interaction of a ship or submarine wake with a thermocline, the collision of a buoyant thermal with a temperature inversion, and the interaction of a vortex flow with a flame front. This problem also serves as a generic model for turbulent mixing and entrainment processes across sharp density interfaces. The interaction between vortices and a free surface, with corresponds to the case where the density jump is very large, has been studied fairly extensively, both experimentally and computationally. By comparison, the literature for the more general case of vortex pairs and rings interacting with sharp density interfaces is relatively sparse. Experiments and numerical studies have been performed, but the numerical simulations were confined primarily to vortex pairs, restricted to the inviscid case, and the effect of density variation modeled under the Boussinesq approximation. The experiments were also confined to the Boussinesq regime. In this paper, we study the motion of a vortex ring in a sharply stratified, viscous fluid via a numerical solution of the full Navier-Stokes equations with finite-amplitude density variation. both Boussinesq and non-Boussinesq flow regimes will be studied, the effect of viscosity on the interaction will be examined, and three-dimensional aspects of the motion will be addressed, such as Widnall instability of the vortex ring and vortex reconnection at the interface.

Marcus, D.L.; Bell, J.B.

1990-10-01T23:59:59.000Z

264

Magnetorotational instability, current relaxation, and current-vortex sheet  

SciTech Connect

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.

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)

2013-08-15T23:59:59.000Z

265

Vortex Dynamics for the Ginzburg-Landau-Schrödinger Equation  

E-Print Network (OSTI)

The initial value problem for the Ginzburg-Landau-Schr\\"odinger equation is examined in the $\\epsilon \\rightarrow 0$ limit under two main assumptions on the initial data $\\phi^\\epsilon$. The first assumption is that $\\phi^\\epsilon$ exhibits $m$ distinct vortices of degree $\\pm 1$; these are described as points of concentration of the Jacobian $[J\\phi^\\epsilon]$ of $\\phi^\\epsilon$. Second, we assume energy bounds consistent with vortices at the points of concentration. Under these assumptions, we identify ``vortex structures'' in the $\\epsilon \\rightarrow 0$ limit of $\\phi^\\epsilon$ and show that these structures persist in the solution $u^\\epsilon(t)$ of $GLS_\\epsilon$. We derive ordinary differential equations which govern the motion of the vortices in the $\\epsilon \\rightarrow 0$ limit. The limiting system of ordinary differential equations is a Hamitonian flow governed by the renormalized energy of Bethuel, Brezis and H\\'elein. Our arguments rely on results about the structural stability of vortices which are proved in a separate paper.

James Ellis Colliander; Robert L. Jerrard

1997-12-12T23:59:59.000Z

266

Field-Reversed Configuration Power Plant Critical-Issue Scoping Study  

SciTech Connect

A team from the Universities of Wisconsin, Washington, and Illinois performed an engineering scoping study of critical issues for field-reversed configuration (FRC) power plants. The key tasks for this research were (1) systems analysis for deuterium-tritium (D-T) FRC fusion power plants, and (2) conceptual design of the blanket and shield module for an FRC fusion core. For the engineering conceptual design of the fusion core, the project team focused on intermediate-term technology. For example, one decision was to use steele structure. The FRC systems analysis led to a fusion power plant with attractive features including modest size, cylindrical symmetry, good thermal efficiency (52%), relatively easy maintenance, and a high ratio of electric power to fusion core mass, indicating that it would have favorable economics.

Santarius, J. F.; Mogahed, E. A.; Emmert, G. A.; Khater, H. Y.; Nguyen, C. N.; Ryzhkov, S. V.; Stubna, M. D.

2000-03-31T23:59:59.000Z

267

Reversible chemisorption on highly dispersed Ru catalysts  

SciTech Connect

Hydrogen and carbon monoxide adsorptions have been studied by static gas volumetric measurement on a range of highly dispersed Y-zeolite-supported ruthenium catalysts prepared by ion exchange. At ambient temperature, the absorption isotherms indicated two distinct types of adsorption - reversible (composed of both physisorption and weak chemisorption) and irreversible (strongly chemisorbed). The catalysts were highly dispersed and had average particle diameters ranging from 0.9 to 1.6 nm. Reversible hydrogen chemisorption was found to be a function of average particle diameter and dispersion. On the other hand, reversible carbon monoxide chemisorption seemed to be mainly due to interaction with the support.

Yang, C.H.; Goodwin, J.G. Jr.

1982-11-01T23:59:59.000Z

268

Reverse osmosis desalination: Modeling and experiment  

Science Journals Connector (OSTI)

An analytic model for the performance of reverse osmosis desalination systems is derived. Predictions are shown to agree well with extensive measurements conducted on a commercial multistage reverse osmosis desalination unit over a broad range of operating conditions. The model allows a transparent understanding of the dependence of system performance on key design and operating variables. Identifying the characteristic flow rate and length scale of reverse osmosis systems allows a universal description of the variation of the permeate flow rate and recovery factor with the salinity flow rate and pressure of the feedwater.

Naum Fraidenraich; Olga C. Vilela; Gilmário A. Lima; Jeffrey M. Gordon

2009-01-01T23:59:59.000Z

269

Microsoft Word - IronCore  

NLE Websites -- All DOE Office Websites (Extended Search)

November/December 2013 November/December 2013 Percolation Explains How Earth's Iron Core Formed The formation of Earth's metallic core, which makes up a third of our planet's mass, represents the most significant differentiation event in Earth's history. Earth's present layered structure with a metallic core and an overlying silicate mantle would have required mechanisms to separate iron alloy from a silicate phase. Percolation of liquid iron alloy moving through a solid silicate matrix (much as water percolates through porous rock, or even coffee grinds) has been proposed as a possible model for core formation (Figure 1). Many previous experimental results have ruled out percolation as a major core formation mechanism for Earth at the relatively lower pressure conditions in the upper mantle, but

270

Increasing liquid hydrocarbon recovery from natural gas: Evaluation of the vortex-tube device  

SciTech Connect

The vortex-tube device provides a useful addition to the range of equipment available to the gas industry. It has been shown that the use of vortex-tube equipment permits improved separation in comparison with a Joule-Thomson system, without entering into the cost and complexity of a true isentropic system such as a turbo-expander unit. The comparative advantage of the vortex tube depends upon the inlet conditions of the gas and the pressure drop that is available. An optimum pressure drop of 25--35% of the inlet gas pressure has been confirmed in practice. Although not yet tested on operating plant, it is expected that a loss of performance of vortex-tube units will occur for inlet liquid-to-gas ratios of greater than 20%. Units with up to 5% liquid at the inlet have been successfully operated showing that a single phase gas at the unit inlet is not essential. It is expected that future application of vortex tube units will be concentrated where performance improvements over Joule-Thomson units, at low capital cost, are required.

Hajdik, B. [CBS Engineering, Houston, TX (United States); Steinle, J. [BEB Erdoel and Erdgas GmbH, Hannover (Germany); Lorey, M. [Filtan Analgenbau GmbH, Langenselbold (Germany); Thomas, K. [Falk and Thomas Engineering GmbH, Wettenberg (Germany)

1997-12-31T23:59:59.000Z

271

Direct Imaging of Asymmetric Magnetization Reversal  

NLE Websites -- All DOE Office Websites (Extended Search)

Direct Imaging of Asymmetric Magnetization Reversal Print Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron microscopy at the ALS to directly image the magnetic structure of an exchange-biased film, a team from the University of Washington and the Stanford Synchrotron Radiation Laboratory has identified separate magnetic-reversal mechanisms in the two branches of a hysteresis loop. This advance in fundamental understanding will provide new insights for developing the next generation of information storage and sensing devices where exchange bias is expected to play a critical role.

272

Reversing the Circulation of Magnetic Vortices  

NLE Websites -- All DOE Office Websites (Extended Search)

Reversing the Circulation of Reversing the Circulation of Magnetic Vortices Reversing the Circulation of Magnetic Vortices Print Wednesday, 31 July 2013 00:00 In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can be oriented clockwise or counterclockwise. Previous studies have shown that the polarity can be flipped on command. Now, using time-resolved magnetic soft x-ray microscopy at the ALS, researchers have shown for the first time how to use pulsed magnetic fields to reverse the circulation.

273

Subsurface imaging with reverse vertical seismic profiles  

E-Print Network (OSTI)

This thesis presents imaging results from a 3D reverse vertical seismic profile (RVSP) dataset measured at a hydrocarbon bearing pinnacle reef in northern Michigan. The study presented many challenges in seismic data ...

Krasovec, Mary L. (Mary Lee), 1972-

2001-01-01T23:59:59.000Z

274

How to reverse-engineer quality rankings  

Science Journals Connector (OSTI)

A good or bad product quality rating can make or break an organization. However, the notion of “quality” is often defined by an independent rating ... step in this process is to “reverse-engineer” a rating compan...

Allison Chang; Cynthia Rudin; Michael Cavaretta; Robert Thomas…

2012-09-01T23:59:59.000Z

275

Landfill Leachate Treatment by Reverse Osmosis  

Science Journals Connector (OSTI)

Leachate from landfill sites represents a highly polluted waste water. It containes biodegradable compounds but also inorganic salts and trace recalcitrant pollutants. The reverse osmosis process with or without ...

B. Weber; F. Holz

1991-01-01T23:59:59.000Z

276

Fuel Cell Technologies Office: Reversible Fuel Cells Workshop  

NLE Websites -- All DOE Office Websites (Extended Search)

Reversible Fuel Cells Reversible Fuel Cells Workshop to someone by E-mail Share Fuel Cell Technologies Office: Reversible Fuel Cells Workshop on Facebook Tweet about Fuel Cell Technologies Office: Reversible Fuel Cells Workshop on Twitter Bookmark Fuel Cell Technologies Office: Reversible Fuel Cells Workshop on Google Bookmark Fuel Cell Technologies Office: Reversible Fuel Cells Workshop on Delicious Rank Fuel Cell Technologies Office: Reversible Fuel Cells Workshop on Digg Find More places to share Fuel Cell Technologies Office: Reversible Fuel Cells Workshop on AddThis.com... Publications Program Publications Technical Publications Educational Publications Newsletter Program Presentations Multimedia Conferences & Meetings Annual Merit Review Proceedings Workshop & Meeting Proceedings

277

Highly Reversible Mg Insertion in Nanostructured Bi for Mg Ion...  

NLE Websites -- All DOE Office Websites (Extended Search)

Reversible Mg Insertion in Nanostructured Bi for Mg Ion Batteries. Highly Reversible Mg Insertion in Nanostructured Bi for Mg Ion Batteries. Abstract: Rechargeable magnesium...

278

Materials and System Issues with Reversible SOFC | Department...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Reversible Fuel Cells Workshop Summary Report Advanced Materials for Reversible Solid Oxide Fuel Cell (RSOFC), Dual Mode Operation with Low Degradation Lessons Learned from...

279

Characterization of ion selective membranes for application in reverse  

E-Print Network (OSTI)

Characterization of ion selective membranes for application in reverse electrodialysis systems I would have imagined when I started. i #12;Abstract Reverse electrodialysis (RED) is a renewable

Kjelstrup, Signe

280

Reverse Osmosis for the Separation of Organics from Aqueous Solutions  

Science Journals Connector (OSTI)

Reverse osmosis (RO) has proved reliable and economically ... such effluents often contain organics as solvents. Reverse osmosis is very suitable for the treatment of... Its mod...

R. Rautenbach; I. Janisch

1988-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Discrimination reversal learning in yearling horses  

E-Print Network (OSTI)

DISCRIMINATION REVERSAL LEARNING IN YEARLING HORSES A Thesis by JEANNA CHASTAIN FISKE Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE December 1976... Major Subjects Animal Science DISCRIMINATION REVERSAL LEARNING IN YEARLING HORSES A Thesis by JEANNA CHASTAIN FISKE Approved as to style and content by& Chai an o Committee ad oi epartment Member Nem er December 1976 ABSTRACT Discrimination...

Fiske, Jeanna Chastain

1976-01-01T23:59:59.000Z

282

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

SciTech Connect

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.

Ahsan Choudhuri

2011-03-31T23:59:59.000Z

283

Joule heating induced by vortex motion in a type-II superconductor Z. L. Xiao and E. Y. Andrei  

E-Print Network (OSTI)

Joule heating induced by vortex motion in a type-II superconductor Z. L. Xiao and E. Y. Andrei-II superconductor due to Joule heating induced by vortex motion. The effect of Joule heating is detected s duration, where the Joule heating is negligible and saturates, respectively. The thermometry is based

Andrei, Eva Y.

284

Method for the assessment of airborne off-target pesticide spray concentrations due to aircraft wing-tip vortex  

E-Print Network (OSTI)

that spherical spray droplets are transported by a two dimensional parametric representation of a spray-engulfing aircraft wing-tip vortex pair. Two distinctive flow regions were considered for the spray-vortex dynamics. The first occurs in the vicinity...

Oliva, Sergio Eduardo

2012-06-07T23:59:59.000Z

285

Counter-rotating vortex patches in shear: a model of the effect of wind shear on aircraft trailing vortices  

Science Journals Connector (OSTI)

...significantly a following passenger-containing aircraft and cause an accident. For example, the vortex wake of a Boeing 747 can rotate a Boeing 737 through 45 . This problem is called the trailing-vortex hazard, and since the trailing vortices can...

2002-01-01T23:59:59.000Z

286

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

E-Print Network (OSTI)

of existence, their duration a problem of stability and if there are several we have a problem of vortex mecha- nism is that the bubble loses impulse as the radius of the ring grows due to viscous decay of circulation 6 . A further theory suggests that the vortex bubble the ambient fluid car- ried along

Bolster, Diogo

287

Observation of Hybrid Soliton Vortex-Ring Structures in Bose-Einstein Condensates Naomi S. Ginsberg,1,* Joachim Brand,2  

E-Print Network (OSTI)

-Einstein condensates. We examine both their creation via soliton-vortex collisions and their subsequent development into vortex rings (VRs) [7,8] via the Kadomtsev-Petviashvili, or ``snake,'' instability [9]. In this Letter frequencies !z 2 21 Hz and !x !y 3:0!z in our 4-Dee magnetic trap [14]. We work at temperatures well below

Hau, Lene Vestergaard

288

Reduction of vortex induced forces and motion through surface roughness control  

DOE Patents (OSTI)

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.

Bernitsas, Michael M; Raghavan, Kamaldev

2014-04-01T23:59:59.000Z

289

Experimental study of vortex generators effects on low Reynolds number airfoils in turbulent flow  

Science Journals Connector (OSTI)

In the present work, we study the aerodynamic effects of triangular vortex generators, as passive flow control devices, placed on the upper surface of an airfoil submitted to a low Reynolds number turbulent flow. In the experiments, different configurations of those devices have been studied. An Eppler 387 airfoil was used. The tests were performed in a turbulent boundary layer wind tunnel using a two component aerodynamic balance and flow visualisation systems. Turbulent flow characterisation was made by means of hot wire anemometry. Calculations of local turbulent intensity as well as temporal and spatial turbulent scales were made. Vortex generators were located at 10% and 20% of the airfoil chord from the leading edge, modifying its angle of incidence refereed to the free stream. The results show changes in the aerodynamic section coefficients, C1, Cd and C1, for the different vortex generator configurations. Neither hysteresis effects, nor leading edge bubbles were found in the experiments.

Juan Sebastián Delnero; Julio Marañon Di Leo; Mauricio Ezequiel Camocardi; Mariano A. Martinez; Jorge L. Colman Lerner

2012-01-01T23:59:59.000Z

290

Novel vortex dynamics in untwinned YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} single crystals  

SciTech Connect

Magnetotransport measurements on a clean, untwinned YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} single crystal show that the vortex dynamics at temperatures just below the vortex lattice melting transition are highly dependent on the type of modulation of the probing current. While in the case of DC current the flux flow is disordered, the {open_quotes}shaking{close_quotes} of the vortex lattice by a square-wave current leads to a more uniform vortex motion. A small asymmetry ({approximately}10%) in the durations of the positive and negative parts of the square-wave period induces periodical oscillations of the voltage response amplitude. The period of oscillations ({approximately}100 s) is the same order of magnitude as the time needed for vortices to cross the sample (transit time). The authors relate the observed voltage oscillations to a periodically ordered vortex motion.

Gordeev, S.N.; Oussena, M.; Pinfold, S.; Langan, R.M. [Univ. of Southampton (United Kingdom)] [and others

1996-12-01T23:59:59.000Z

291

Formation of a flux core spheromak  

Science Journals Connector (OSTI)

An alternate design for compact tori specifically of the spheromak type is studied. In this design the ‘‘flux core spheromak’’ [Nucl. Fusion 29 219 (1989)] the externally imposed bias field links the confinement region of closed flux surfaces. The advantages of this configuration are: (i) it enjoys greater stability to magnetohydrodynamic (MHD) modes particularly the tilt and shift; (ii) it has a poloidal divertor and an amount of poloidal flux separating the closed flux surface region from the walls; and (iii) it might be sustained by helicity injection. Results are presented showing the dependence of the geometry on the distribution of bias flux on the conducting walls and showing the optimization of the 2?D formation scheme to minimize the contact of the plasma with coils electrodes and walls. This last topic involves taking advantage of current sheet formation and subsequent tearing as in formation of the MS spheromak [Phys. Fluids 28 3154 (1985)]. The parameters which can be varied to produce this favorable formation scheme via tearing rather than a formation that proceeds off the reversal coils are explored. In addition it is found that there is strong viscous heating of the ions in this early reconnection phase.

John M. Finn; Parvez N. Guzdar

1991-01-01T23:59:59.000Z

292

Phase-locking of driven vortex lattices with transverse ac force and periodic pinning  

SciTech Connect

For a vortex lattice moving in a periodic array we show analytically and numerically that a new type of phase locking occurs in the presence of a longitudinal dc driving force and a transverse ac driving force. This phase locking is distinct from the Shapiro step phase locking found with longitudinal ac drives. We show that an increase in critical current and a fundamental phase-locked step width scale with the square of the driving ac amplitude. Our results should carry over to other systems such as vortex motion in Josephson-junction arrays.

Reichhardt, Charles; Kolton, Alejandro B.; Dominguez, Daniel; Gronbech-Jensen, Niels

2001-10-01T23:59:59.000Z

293

Low-temperature vortex dynamics in a high-temperature superconductor  

Science Journals Connector (OSTI)

Magnetic-field gradients in the mixed state of a type-II superconductor are studied using Tl205 nuclear magnetic resonance (NMR) on Tl2Ba2Ca2Cu3O10+?. An anomalous peak was observed in the temperature dependence of the transverse relaxation rate at T/Tc?0.25. We attribute this behavior to magnetic-field flucutations from vortex dynamics. We interpret this behavior as a crossover of the principal time scale for vortex dynamics with that of the NMR experiment, approximately 100 ?s. The temperature dependence of this time scale is discussed.

Y.-Q. Song; S. Tripp; W. P. Halperin; L. Tonge; T. J. Marks

1994-12-01T23:59:59.000Z

294

The effects of a jet on vortex breakdown over a sharp leading-edge delta wing  

E-Print Network (OSTI)

THE EFFECTS OF A JET ON VORTEX BREAKDOWN OVER A SHARP LEADING-EDGE DELTA WING A Thesis Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE December 1985... Major Subject: Aerospace Engineering THE EFFECTS OF A JET ON VORTEX BREAKDOWN OVER A SHARP LEADING-EDGE DELTA WING A Thesis by IAN KENNETH MAYNARD Approved as to style and content by: Cyrus Ostowar (Chairman of Committee) Stan J Miley (M er...

Maynard, Ian Kenneth

2012-06-07T23:59:59.000Z

295

Dynamic switching of the circulation in tapered magnetic nanodisks  

E-Print Network (OSTI)

spin structure of magnetic vortex cores. Science 298, 577 (Magnetic vortex core observation in circular dots of permalloy. Science

Uhlir, V.

2014-01-01T23:59:59.000Z

296

Alkali solution treatment on sandstone cores  

E-Print Network (OSTI)

was used for filtering the solution before the injection into the core. Hassler-t e Core Holder A stainless steel core holder was used to hold the core for treatment with the solutions. The core sample was positioned in the center of the core holder... and heat the water in the flask. Electric Heatin Ta e A silicone rubber embedded flexible heating tape was used to wrap the core holder to heat the core sample to the desired temperature. The maximum 0 continuous operating temperature of the tape...

Lee, Suk Jin

2012-06-07T23:59:59.000Z

297

Reverse-Engineering Banks' Financial Strength Ratings Using ...  

E-Print Network (OSTI)

Dec 27, 2006 ... reverse-engineering a superior bank rating system, which turns out to ...... sector (

mal92

2009-05-16T23:59:59.000Z

298

Reversed Doppler effect under reflection from a shock electromagnetic wave  

Science Journals Connector (OSTI)

The possibility of observing the reversed Doppler effect in an electrodynamic system of coupled transmission...

A. M. Belyantsev; A. B. Kozyrev

2002-11-01T23:59:59.000Z

299

Reversing the Circulation of Magnetic Vortices  

NLE Websites -- All DOE Office Websites (Extended Search)

Reversing the Circulation of Magnetic Vortices Print Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can be oriented clockwise or counterclockwise. Previous studies have shown that the polarity can be flipped on command. Now, using time-resolved magnetic soft x-ray microscopy at the ALS, researchers have shown for the first time how to use pulsed magnetic fields to reverse the circulation.

300

Reversing the Circulation of Magnetic Vortices  

NLE Websites -- All DOE Office Websites (Extended Search)

Reversing the Circulation of Magnetic Vortices Print Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can be oriented clockwise or counterclockwise. Previous studies have shown that the polarity can be flipped on command. Now, using time-resolved magnetic soft x-ray microscopy at the ALS, researchers have shown for the first time how to use pulsed magnetic fields to reverse the circulation.

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Reversing the Circulation of Magnetic Vortices  

NLE Websites -- All DOE Office Websites (Extended Search)

Reversing the Circulation of Magnetic Vortices Print Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can be oriented clockwise or counterclockwise. Previous studies have shown that the polarity can be flipped on command. Now, using time-resolved magnetic soft x-ray microscopy at the ALS, researchers have shown for the first time how to use pulsed magnetic fields to reverse the circulation.

302

Reversing the Circulation of Magnetic Vortices  

NLE Websites -- All DOE Office Websites (Extended Search)

Reversing the Circulation of Magnetic Vortices Print Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can be oriented clockwise or counterclockwise. Previous studies have shown that the polarity can be flipped on command. Now, using time-resolved magnetic soft x-ray microscopy at the ALS, researchers have shown for the first time how to use pulsed magnetic fields to reverse the circulation.

303

Reversing the Circulation of Magnetic Vortices  

NLE Websites -- All DOE Office Websites (Extended Search)

Reversing the Circulation of Magnetic Vortices Print Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can be oriented clockwise or counterclockwise. Previous studies have shown that the polarity can be flipped on command. Now, using time-resolved magnetic soft x-ray microscopy at the ALS, researchers have shown for the first time how to use pulsed magnetic fields to reverse the circulation.

304

Development of an integrated reverse engineering system  

Science Journals Connector (OSTI)

This paper describes the development of a customised reverse engineering system in which a 3D digitiser (MicroScribe-3DX) has been integrated with a computer-aided design (CAD) system (Pro/ENGINEER). The application programme written in C language enables a real-time input from the digitiser to Pro/ENGINEER. Two Application Programming Interfaces (APIs) were used: the MicroScribe-3D Software Development Kit (SDK) and Pro/TOOLKIT. The former allows the user to develop an integrated system through intuitive and high-level function calls to the digitiser. The latter enables a user to customise a Pro/ENGINEER environment. This system offers an intuitive and user-friendly means for reverse engineering. It also helps to shorten the whole reverse engineering process. This is because the digitised data can be displayed and edited in real time, so that early identification and exclusion of the undesired and incorrect data are made possible.

X.W. Xu; L. Song

2006-01-01T23:59:59.000Z

305

Optimal design of reverse osmosis module networks  

SciTech Connect

The structure of individual reverse osmosis modules, the configuration of the module network, and the operating conditions were optimized for seawater and brackish water desalination. The system model included simple mathematical equations to predict the performance of the reverse osmosis modules. The optimization problem was formulated as a constrained multivariable nonlinear optimization. The objective function was the annual profit for the system, consisting of the profit obtained from the permeate, capital cost for the process units, and operating costs associated with energy consumption and maintenance. Optimization of several dual-stage reverse osmosis systems were investigated and compared. It was found that optimal network designs are the ones that produce the most permeate. It may be possible to achieve economic improvements by refining current membrane module designs and their operating pressures.

Maskan, F.; Wiley, D.E.; Johnston, L.P.M.; Clements, D.J.

2000-05-01T23:59:59.000Z

306

Reversed Doppler Effect in Photonic Crystals  

Science Journals Connector (OSTI)

Nonrelativistic reversed Doppler shifts have never been observed in nature and have only been speculated to occur in pathological systems with simultaneously negative effective permittivity and permeability. This Letter presents a different, new physical phenomenon that leads to a nonrelativistic reversed Doppler shift in light. It arises when light is reflected from a moving shock wave propagating through a photonic crystal. In addition to reflection of a single frequency, multiple discrete reflected frequencies or a 10 GHz periodic modulation can also be observed when a single carrier frequency of wavelength 1????m is incident.

Evan J. Reed; Marin Solja?i?; John D. Joannopoulos

2003-09-23T23:59:59.000Z

307

Tropical cyclone genesis efficiency: mid-level versus bottom vortex Xuyang Ge and Tim Li  

E-Print Network (OSTI)

;4 1. Introduction Tropical cyclone (TC) genesis is the least understood phase in a TC life cycle is cyclogenesis in an environment with a mid-level vortex (EMV). An analysis of the WNP TC genesis in 2000 the QuikSCAT-derived surface wind observations, there was no sign

Li, Tim

308

Cherenkov resonances in vortex dissipation in superconductors B. I. Ivlev and S. Mejia-Rosales  

E-Print Network (OSTI)

, Mexico M. N. Kunchur Department of Physics and Astronomy, University of South Carolina, Columbia, South-two superconductors the magnetic flux is carried by vortices. If the transport electric current greatly exceeds in the crystal the dissipa- tion increases due to Cherenkov emission of sound waves. Each moving vortex creates

Kunchur, Milind N.

309

DETECTION OF VORTEX TUBES IN SOLAR GRANULATION FROM OBSERVATIONS WITH SUNRISE  

SciTech Connect

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.

Steiner, O.; Franz, M.; Bello Gonzalez, N.; Nutto, Ch.; Rezaei, R.; Schmidt, W. [Kiepenheuer-Institut fuer Sonnenphysik, Schoeneckstrasse 6, 79104 Freiburg (Germany); Martinez Pillet, V.; Bonet Navarro, J. A. [Instituto de Astrofisica de Canarias, 38200, La Laguna, Tenerife (Spain); Del Toro Iniesta, J. C. [Instituto de Astrofisica de Andalucia (CSIC), Apdo. de Correos 3004, 18080 Granada (Spain); Domingo, V. [Grupo de Astronomia y Ciencias del Espacio, Universidad de Valencia, 46980 Paterna, Valencia (Spain); Solanki, S. K.; Barthol, P.; Gandorfer, A. [Max-Planck-Institut fuer Sonnensystemforschung, 37191 Katlenburg-Lindau (Germany); Knoelker, M., E-mail: steiner@kis.uni-freiburg.d [High Altitude Observatory, National Center for Atmospheric Research (NCAR), Boulder, CO 80307-3000 (United States)

2010-11-10T23:59:59.000Z

310

ADVANCES IN ATMOSPHERIC SCIENCES, VOL. 27, NO. 2, 2010, 243252 Mesoscale Barotropic Instability of Vortex Rossby  

E-Print Network (OSTI)

ADVANCES IN ATMOSPHERIC SCIENCES, VOL. 27, NO. 2, 2010, 243­252 Mesoscale Barotropic Instability of Vortex Rossby Waves in Tropical Cyclones ZHONG Wei1 ( Í), LU Han-Cheng1 (ö ), and Da-Lin ZHANG2 1 Institute of Meteorology, PLA University of Science and Technology, Nanjing 211101 2 Department

Zhang, Da-Lin

311

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

E-Print Network (OSTI)

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

Dalziel, Stuart

312

Particle resuspension by an impacting vortex ring RICK J. MUNRO & STUART B. DALZIEL  

E-Print Network (OSTI)

Particle resuspension by an impacting vortex ring RICK J. MUNRO & STUART B. DALZIEL Department results from a set of visualization experiments conducted to analyse the hydrodynamic resuspension of particles from a thick horizontal sediment layer. The mechanism employed to produce the resuspension

Dalziel, Stuart

313

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

E-Print Network (OSTI)

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

Dalziel, Stuart

314

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

Science Journals Connector (OSTI)

This paper presents results from an experimental investigation of the interaction of a vortex ring with a particle layer. The flowdynamics during the onset of particle resuspension are analysed using particle image velocimetry while a light attenuation method provides accurate measurements of the final eroded crater shape. This work is a continuation of the research described in R. J. Munro N. Bethke and S. B. Dalziel “Sediment resuspension and erosion by vortex rings ” Phys. Fluids21 046601 (2009)10.1063/1.3083318 which focussed on the general resuspension onset dynamics and initial crater formation. Here we analyse the velocity induced by the vortex ring on the particle layer surface during the resuspension of particles for different particle sizes and the shape and size of the final craters that are formed by the impact of the vortex ring. We find that the boundary condition is characterised by a quasi-slip velocity at the particle layer surface independent of the particle size. The particle diameter and thus bed permeability is found to have a significant effect on the final crater characteristics.

N. Bethke; S. B. Dalziel

2012-01-01T23:59:59.000Z

315

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

E-Print Network (OSTI)

Resuspension onset and crater erosion by a vortex ring interacting with a particle layer N. Bethke://pof.aip.org/features/most_downloaded Information for Authors: http://pof.aip.org/authors #12;PHYSICS OF FLUIDS 24, 063301 (2012) Resuspension onset layer. The flow dynamics during the onset of particle resuspension are analysed using particle image

Dalziel, Stuart

316

Tip Vortex Field Resolution Using an Adaptive Dual-Mesh Computational Nathan Hariharan  

E-Print Network (OSTI)

for the aforementioned unsteady, vortical fields. 1. Introduction 1.1 Background Vortical wakes introduce important AMR in an unstructured Euler solver. Potsdam[3] also applied unstructured AMR to wind turbine wake1 Tip Vortex Field Resolution Using an Adaptive Dual-Mesh Computational Paradigm Nathan Hariharan

Steffen, Michael

317

First-order disorder-driven transition and inverse melting of the vortex lattice  

E-Print Network (OSTI)

`inverse' melting behavior. � 2001 Published by Elsevier Science B.V. Keywords: Type-II superconductivity-order transition (FOT) [1±5] whereas at low temperatures the ordered vortex lattice transforms into a disordered open questions in the phase diagram of HTS is the thermodynamic nature of the disorder-dri- ven

Zeldov, Eli

318

Computational Analysis of a Tip Vortex Structure Shed from a Bioinspired Blade  

E-Print Network (OSTI)

design for this purpose. Different rotor blade designs and relevant insect wings are under study Computational Analysis of a Tip Vortex Structure Shed from a Bioinspired Blade Sebastian was generated with SolidWorks CAD software from measurements performed on a wing sample obtained from

Maccabe, Barney

319

VIVDR -Vortex-induced vibration data repository An overview of available riser datasets  

E-Print Network (OSTI)

VIVDR - Vortex-induced vibration data repository An overview of available riser datasets http://oe.mit.edu/VIV H. Mukundan and M. Triantafyllou 20 April 2008 #12;NDP 38m long riser model datasets #12;33 q Rig q Tension applied through spring-supported clump weights NDP 38m long riser model datasets

320

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

E-Print Network (OSTI)

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

Yang, Jianke

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Effect of asymmetric axial strain on the behavior of the juncture vortex system  

E-Print Network (OSTI)

The objective of this research was to investigate the behavior of the vortex formed in a wing-body juncture in a water tunnel flow. The wing-body juncture was created by mounting a symmetrical airfoil with an elliptical leading edge normal to a flat...

Trosper, Jeffrey Randall

2012-06-07T23:59:59.000Z

322

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

E-Print Network (OSTI)

and mechanical (wind, water flow, vibration, friction and body movement) energies are common in the ambientNanogenerator as an active sensor for vortex capture and ambient wind-velocity detection Rui Zhang principle, ambient wind-speed measurements with the NG are demonstrated. Due to the simple structure, high

Wang, Zhong L.

323

Petrogenesis of the reversely-zoned Turtle pluton, southeastern California  

SciTech Connect

Few plutons with a reversed geometry of a felsic rim and mafic core have been described in the geologic literature. The Turtle pluton of S.E. California is an intrusion composed of a granitic rim and granodioritic core and common microgranitoid enclaves. Field observations, mineral textures and chemistries, major and trace element geochemistry, and isotopic variability support a petrogenetic model of in situ, concomitant, magma mixing and fractional crystallization of rhyolitic magma progressively mixed with an increasing volume of andesitic magma, all without chemical contribution from entrained basaltic enclaves. Hornblende geobarometry indicates the Turtle pluton crystallized at about 3.5 kb. A crystallization sequence of biotite before hornblende (and lack of pyroxenes) suggests the initial granitic magma contained less than 4 wt% H{sub 2}O at temperatures less than 780C. U-Pb, Pb-Pb, Rb-Sr and oxygen isotope studies indicate the terrane intruded by the Turtle pluton is 1.8 Ga, that the Turtle pluton crystallized at 130 Ma, that the Target Granite and garnet aplites are about 100 Ma, and that these intrusions were derived from different sources. Models based on isotopic data suggest the rhyolitic end member magma of the Turtle pluton was derived from mafic igneous rocks, and was not derived from sampled Proterozoic country rocks. Similarity of common Sr and Pb isotopic ratios of these rocks to other Mesozoic intrusions in the Colorado River Region suggest the Turtle pluton and Target Granite have affinities like rocks to the east, including the Whipple Mountains and plutons of western Arizona. P-T-t history of the southern Turtle Mountains implies uplift well into the upper crust by Late Cretaceous time so that the heating and deformation events of the Late Cretaceous and Tertiary observed in flanking ranges did not affect the study area.

Allen, C.M.

1989-01-01T23:59:59.000Z

324

Performance of cholesterol oxidase sequestered within reverse micelles formed in supercritical carbon dioxide  

SciTech Connect

The authors report the first results on an enzyme-induced reaction within the water core of reverse micelles that have been formed in supercritical CO{sub 2} (scCO{sub 2}). By using a perfluoropolyether ammonium carboxylate (PFPE) surfactant, the authors form reverse micelles in scCO{sub 2} with water cores and the authors show that the oxidation of cholesterol by cholesterol oxidase (ChOx) obeys Michaelis-Menten kinetics. The results of their experiments also show that (1) the optimum ChOx activity occurs when the molar ratio of H{sub 2}O-to-PFPE (R) exceeds {approximately}12, (2) the rate constant describing the conversion of the ChOx-cholesterol complex to product ({kappa}{sub cat,app}) is similar to values reported using reverse micelle systems formed in liquid alkanes, (3) the equilibrium constant that describes the ChOx-cholesterol complex dissociation (K{sub m,app}) is optimal at high R values, (4) the best-case K{sub m,app} is {approximately}2-fold better than the value reported using reverse micelles formed in liquid alkanes, (5) there is little change in the ChOx {kappa}{sub cat,app} and K{sub m,app} as the authors adjust the CO{sub 2} pressure between 100 and 260 bar, and (6) the ChOx was active within the PFPE water pool for at least 5 h; however, after 8 or more hours within the PFPE water pool, ChOx became temporarily inactive.

Kane, M.A.; Baker, G.A.; Pandey, S.; Bright, F.V.

2000-05-30T23:59:59.000Z

325

Core Values | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Core Values Core Values Core Values People - People are our most important resource. We respect and use our experience and skills and appreciate our diversity. Business Excellence - We are fiscally responsible and actively pursue best business practices. Safety - We protect our human and material resources and promote safe work practices within the office and at our sites. Communication - We take full advantage of our virtual organization's strengths and share information freely across all levels of the organization. Leadership and Teamwork - We encourage leadership and teamwork at all levels of the organization. We value active participation and demonstrate respect for each other. Customer Service - We openly communicate with all our customers in a timely manner and actively seek opportunities to improve our services.

326

Definition: Core Analysis | Open Energy Information  

Open Energy Info (EERE)

Core Analysis Core Analysis Jump to: navigation, search Dictionary.png Core Analysis Core samples are obtained from drilling a well, typically using a synthetic diamond coated bit that has a hollow center so cylindrical rock samples ("core") can be extracted. Core samples successfully recovered are visually inspected to determine rock type, mineralization, and fracture networks, then certain laboratory analyses may ensue to acquire detailed rock properties. View on Wikipedia Wikipedia Definition A core sample is a cylindrical section of (usually) a naturally occurring substance. Most core samples are obtained by drilling with special drills into the substance, for example sediment or rock, with a hollow steel tube called a core drill. The hole made for the core sample is

327

Multi-core Performance Analysis  

NLE Websites -- All DOE Office Websites (Extended Search)

core Performance Analysis core Performance Analysis HPC Computation 1 Performance Analysis * Compiler Feedback * HWPC Data * Load Balance 2 Compiler Feedback * Before optimizing code, it's critical to know what the compiler does to your code - Loop optimizations - Vectorization - Prefetching - ... * Equally important to what the compiler does is what it doesn't do, and why - Data dependencies - Misplaced branches - Unknown loop counts - ... 3 Enabling Compiler Feedback * Portland Group - Minfo=all - Mneginfo - Minfo=ccff (Common Compiler Feedback Format) * Cray - rm (Fortran) - hlist=m (C/C++) * Intel - vec-report1 * Pathscale - LNO:simd_verbose=ON:vintr_verbose=ON:prefetch_v erbose=ON * GNU - ftree-vectorizer-verbose=1

328

An Explanation for Beta's Mean-reversion  

E-Print Network (OSTI)

for the designation as an UNDERGRADUATE RESEARCH SCHOLAR Approved by Research Advisor: Dr. Dennis Jansen May 2014 Major: Economics TABLE OF CONTENTS Page ABSTRACT.................................................................................................................................. 8 1 ABSTRACT An Explanation for Beta’s Mean Reversion. (May 2014) Connor Matthew Bodkin Department of Economics Texas A&M University Research Advisor: Dr. Dennis Jansen Department of Economics This study aims to improve upon...

Bodkin, Connor Matthew

2013-09-26T23:59:59.000Z

329

Mitochondrial modulation: reversible phosphorylation takes center stage?  

E-Print Network (OSTI)

.5 billion years, mitochondria have evolved from oxygen-scavenging bacterial symbionts into pri- mary controlMitochondrial modulation: reversible phosphorylation takes center stage? David J. Pagliarini1 and Center for Human Genetics Research, Massachusetts General Hospital, Boston, MA 02114, USA In the past 1

Pagliarini, David J.

330

Reversing entanglement change by a weak measurement  

E-Print Network (OSTI)

PHYSICAL REVIEW A 82, 052323 (2010) Reversing entanglement change by a weak measurement Qingqing Sun,1,* M. Al-Amri,2 Luiz Davidovich,3 and M. Suhail Zubairy1 1Department of Physics and Institute for Quantum Science and Engineering, Texas A...

Sun, Qingqing; Al-Amri, M.; Davidovich, Luiz; Zubairy, M. Suhail.

2010-01-01T23:59:59.000Z

331

Compact Reversed-Field Pinch Reactors (CRFPR): preliminary engineering considerations  

SciTech Connect

The unique confinement physics of the Reversed-Field Pinch (RFP) projects to a compact, high-power-density fusion reactor that promises a significant reduction in the cost of electricity. The compact reactor also promises a factor-of-two reduction in the fraction of total cost devoted to the reactor plant equipment (i.e., fusion power core (FPC) plus support systems). In addition to operational and developmental benefits, these physically smaller systems can operate economically over a range of total power output. After giving an extended background and rationale for the compact fusion approaches, key FPC subsystems for the Compact RFP Reactor (CRFPR) are developed, designed, and integrated for a minimum-cost, 1000-MWe(net) system. Both the problems and promise of the compact, high-power-density fusion reactor are quantitatively evaluated on the basis of this conceptual design. The material presented in this report both forms a framework for a broader, more expanded conceptual design as well as suggests directions and emphases for related research and development.

Hagenson, R.L.; Krakowski, R.A.; Bathke, C.G.; Miller, R.L.; Embrechts, M.J.; Schnurr, N.M.; Battat, M.E.; LaBauve, R.J.; Davidson, J.W.

1984-08-01T23:59:59.000Z

332

Large core fiber optic cleaver  

DOE Patents (OSTI)

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.

Halpin, J.M.

1996-03-26T23:59:59.000Z

333

Stellar core collapse and supernova  

SciTech Connect

Massive stars that end their stable evolution as their iron cores collapse to a neutron star or black hole long been considered good candidates for producing Type II supernovae. For many years the outward propagation of the shock wave produced by the bounce of these iron cores has been studied as a possible mechanism for the explosion. For the most part, the results of these studies have not been particularly encouraging, except, perhaps, in the case of very low mass iron cores or very soft nuclear equations of state. The shock stalls, overwhelmed by photodisintegration and neutrino losses, and the star does not explode. More recently, slow late time heating of the envelope of the incipient neutron star has been found to be capable of rejuvenating the stalled shock and producing an explosion after all. The present paper discusses this late time heating and presents results from numerical calculations of the evolution, core collapse, and subsequent explosion of a number of recent stellar models. For the first time they all, except perhaps the most massive, explode with reasonable choices of input physics. 39 refs., 17 figs., 1 tab.

Wilson, J.R.; Mayle, R.; Woosley, S.E.; Weaver, T.

1985-04-01T23:59:59.000Z

334

Stability of Molten Core Materials  

SciTech Connect

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.

Layne Pincock; Wendell Hintze

2013-01-01T23:59:59.000Z

335

Wright State University CORE Scholar  

E-Print Network (OSTI)

Wright State University CORE Scholar Psychology Faculty Publications Psychology 10-1-2010 The Statistical Properties of the Survivor Interaction Contrast Joseph W. Houpt Wright State University - Main Campus, joseph.houpt@wright.edu James T. Townsend Follow this and additional works at: http://corescholar.libraries.wright

Townsend, James T.

336

Tropical Cyclone Initialization with a Spherical High-Order Filter and an Idealized Three-Dimensional Bogus Vortex  

Science Journals Connector (OSTI)

A tropical cyclone initialization method with an idealized three-dimensional bogus vortex of an analytic empirical formula is presented for the track and intensity prediction. The procedure in the new method consists of four steps: the separation ...

In-Hyuk Kwon; Hyeong-Bin Cheong

2010-04-01T23:59:59.000Z

337

Logging-while-coring method and apparatus  

DOE Patents (OSTI)

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.

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

2007-11-13T23:59:59.000Z

338

A REVERSE SHOCK IN GRB 130427A  

SciTech Connect

We present extensive radio and millimeter observations of the unusually bright GRB 130427A at z = 0.340, spanning 0.67-12 days after the burst. We combine these data with detailed multi-band UV, optical, NIR, and Swift X-ray observations and find that the broadband afterglow emission is composed of distinct reverse shock and forward shock contributions. The reverse shock emission dominates in the radio/millimeter and at ?< 0.1 days in the UV/optical/NIR, while the forward shock emission dominates in the X-rays and at ?> 0.1 days in the UV/optical/NIR. We further find that the optical and X-ray data require a wind circumburst environment, pointing to a massive star progenitor. Using the combined forward and reverse shock emission, we find that the parameters of the burst include an isotropic kinetic energy of E{sub K,{sub iso}} ? 2 × 10{sup 53} erg, a mass loss rate of M-dot ?3×10{sup -8} M{sub ?} yr{sup –1} (for a wind velocity of 1000 km s{sup –1}), and a Lorentz factor at the deceleration time of ?(200 s) ? 130. Due to the low density and large isotropic energy, the absence of a jet break to ?15 days places only a weak constraint on the opening angle, ?{sub j} ?> 2.°5, and therefore a total energy of E{sub ?} + E{sub K} ?> 1.2 × 10{sup 51} erg, similar to other gamma-ray bursts (GRBs). The reverse shock emission is detectable in this burst due to the low circumburst density, which leads to a slow cooling shock. We speculate that this property is required for the detectability of reverse shocks in radio and millimeter bands. Following on GRB 130427A as a benchmark event, observations of future GRBs with the exquisite sensitivity of the Very Large Array and ALMA, coupled with detailed modeling of the reverse and forward shock contributions, will test this hypothesis.

Laskar, T.; Berger, E.; Zauderer, B. A.; Margutti, R.; Soderberg, A. M.; Chakraborti, S.; Lunnan, R.; Chornock, R. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Chandra, P. [National Centre for Radio Astrophysics, Tata Institute of Fundamental Research, Pune University Campus, Ganeshkhind, Pune 411 007 (India); Ray, A. [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005 (India)

2013-10-20T23:59:59.000Z

339

On Reverse Engineering in the Cognitive and Brain Andreas Schierwagen  

E-Print Network (OSTI)

On Reverse Engineering in the Cognitive and Brain Sciences Andreas Schierwagen Institute #12;On Reverse Engineering in the Cognitive and Brain Sciences Andreas Schierwagen Institute research initiatives try to utilize the operational principles of organisms and brains to develop

Schierwagen, Andreas

340

Concentration of ultrafiltered benzylpenicillin broths by reverse osmosis  

Science Journals Connector (OSTI)

...Concentration of benzylpenicillin filtered broths purified by ultrafiltration and fermented broths clarified by ultrafiltration was carried out by reverse osmosis. This study was done using a reverse osmosis l...

A. M. A. Nabais; J. P. Cardoso

2000-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Development of Robust Organosilica Membranes for Reverse Osmosis  

Science Journals Connector (OSTI)

Development of Robust Organosilica Membranes for Reverse Osmosis ... polyamide was also reversible, in other words, the N-chlorinated intermediate could be regenerated to initial amide with the alk. ...

Rong Xu; Jinhui Wang; Masakoto Kanezashi; Tomohisa Yoshioka; Toshinori Tsuru

2011-10-31T23:59:59.000Z

342

Tilt and shift mode stability in a spheromak with a flux core  

Science Journals Connector (OSTI)

The stability of spheromak equilibria with a flux core or reversal coil is studied by means of an ideal magnetohydrodynamic (MHD) code. Results depend critically upon whether the flux hole region (the current free area just inside the separatrix) is treated as a perfectly conducting plasma or as a vacuum. This indicates that the tilt and shift modes persist as resistive instabilities if they are stable in ideal MHD. Specifically for nonoptimally shaped equilibria the flux core must nearly touch the current channel if the flux hole is a vacuum whereas the core may be slightly outside the separatrix if the flux hole has conducting plasma. A larger margin exists for optimally shaped equilibria.

John M. Finn

1984-01-01T23:59:59.000Z

343

E-Print Network 3.0 - arc jet heated Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

Engineering 7 Electrical discharges in theElectrical discharges in the Reverse Vortex FlowReverse Vortex Flow Summary: in Vortex Flows -- ICP Discharge in Vortex FlowsICP...

344

Sakhalin reversal tops C. I. S. action  

SciTech Connect

This paper reports that the outlook for joint ventures in the former U.S.S.R. has been badly muddied by Russia's reversal on one of the biggest investment opportunities: development off Sakhalin Island. Russia's Supreme Council has suspended award of a feasibility study of development of oil and gas reserves off Sakhalin to a combine of Marathon Oil Co., McDermott International, and Mitsui and Co., (MMM). Development project cost is pegged at $9 - 10 billion.

Not Available

1992-02-24T23:59:59.000Z

345

Reverse osmosis desalination with osmotic polyelectrolyte intermediate  

E-Print Network (OSTI)

degree of, '8'~STER O"' SCIENCE '!ay ISS7 Nejo? Subje". t: IiI EQICAE ENO& NEERINC REVERSE OSMOSIS DESALINATION WITH OSMOTIC POLYELECTROLYTE INTERMEDIATE A Thesis By THOMAS THEODORE McCONNELL Approved as to style and content by: airman o... , . . . . . . . . . . 91 Calculated Permeability Coefficients of Mem- branes Using Equation (42) Calculated Desalination Ratio from Equation (34) and Weight Per Cent Rejection from Equa- tion (45) for a 3. 5 Weight Per Cent Sodium Chloride Bulk Solution 92 94 Table...

McConnell, Thomas Theodore

2012-06-07T23:59:59.000Z

346

Progress on the Development of Reversible SOFC Stack Technology  

Energy.gov (U.S. Department of Energy (DOE))

Presentation by Casey Brown, Versa Power Systems, at the NREL Reversible Fuel Cells Workshop, April 19, 2011

347

Methods of classical mechanics applied to turbulence stresses in a tip leakage vortex  

SciTech Connect

Moore et al. measured the six Reynolds stresses in a tip leakage vortex in a linear turbine cascade. Stress tensor analysis, as used in classical mechanics, has been applied to the measured turbulence stress tensors. Principal directions and principal normal stresses are found. A solid surface model, or three-dimensional glyph, for the Reynolds stress tensor is proposed and used to view the stresses throughout the tip leakage vortex. Modeled Reynolds stresses using the Boussinesq approximation are obtained from the measured mean velocity strain rate tensor. The comparison of the principal directions and the three-dimensional graphic representations of the strain and Reynolds stress tensors aids in the understanding of the turbulence and what is required to model it.

Moore, J.G.; Schorn, S.A.; Moore, J. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States)

1996-10-01T23:59:59.000Z

348

A model for vortex-induced vibration analysis of long-span bridges  

Science Journals Connector (OSTI)

Abstract Long-span structures are susceptible to wind-induced vibrations due to their low oscillation frequency and low mechanical damping. Although many efforts have been made in the past to model vortex-induced vibration of circular cylinders, limited studies can be found for non-circular cross sections representative of long-span bridge decks. A model for vortex-induced vibration analysis of long-span bridge is presented in this paper. The aeroelastic equation of motion of the model, a procedure to extract aeroelastic coefficients from wind tunnel experiments, analysis of full-scale structures incorporating loss of spanwise correlation of aeroelastic forces, and comparison between simulated and full-scale measured responses on a twin deck bridge (Fred Hartman bridge, Baytown, Texas) are discussed. Six bluff sections – Deer Isle bridge, Tsurumi bridge, Fred Hartman bridge, generic rectangular, H shaped, and circular models – were considered in this research program.

Mehedy Mashnad; Nicholas P. Jones

2014-01-01T23:59:59.000Z

349

Amplitude distribution of magnetoelastic waves propagating in a vortex field in a superconducting layer  

Science Journals Connector (OSTI)

Magnetic field enters the type ? II superconducting body along a discrete arrangement of magnetic vortex lines. In the dynamic case when the magnetic field vary in time around each such a line a supercurrent flows. So the vorticesinteract one to another with the help of the Lorentz force forming this way a new mechanical field of elastic properties. Moreover those lines arrange themselves in a triangular or quadratic lattice. Such a set is observed if the intensity of the applied to the materialmagnetic field is close to its lower limiting value. The paper aims at investigating amplitude distributions of magnetoelastic waves propagating solely in the vortex field of the superconducting layer. Our attention have been focused on the applied magnetic field intensity influence on those amplitudes for various wave frequencies.

Bogdan T. Maruszewski; Andrzej Drzewiecki; Roman Starosta

2008-01-01T23:59:59.000Z

350

Transition fields during geomagnetic reversals and their geodynamic significance  

Science Journals Connector (OSTI)

...show that for certain reversals, a path midway between the two preferred paths (i...show that for certain reversals, a path midway between the two preferred paths (i...show that for certain reversals, a path midway between the two preferred paths (i...

1997-01-01T23:59:59.000Z

351

The Testing of Geomagnetic Reversal Models: Recent Developments [and Discussion  

Science Journals Connector (OSTI)

20 August 1982 research-article The Testing of Geomagnetic Reversal Models: Recent...data are most useful with regard to the testing of geomagnetic reversal models. First...English illus. United Kingdom 1985 The testing of geomagnetic reversal models; recent...

1982-01-01T23:59:59.000Z

352

Reverse Audio Engineering: Model-Based Inversion of Dynamic Range  

E-Print Network (OSTI)

1 Reverse Audio Engineering: Model-Based Inversion of Dynamic Range Compression Stanislaw Gorlow, Graduate Student Member, IEEE and Joshua D. Reiss, Member, IEEE Abstract--Reverse audio engineering so far, reverse audio engineering. I. INTRODUCTION SOUND or audio engineering is an established discipline

353

Processing of Activated Core Components  

SciTech Connect

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

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

2003-02-26T23:59:59.000Z

354

TMI-2 core shipping preparations  

SciTech Connect

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

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

1988-01-01T23:59:59.000Z

355

Laminated electromagnetic pump stator core  

DOE Patents (OSTI)

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.

Fanning, A.W.

1995-08-08T23:59:59.000Z

356

Control of residual aluminum from conventional treatment to improve reverse osmosis performance  

E-Print Network (OSTI)

Deposit Control for Reverse Osmosis Systems , Technicalon Colloidal Fouling in Reverse Osmosis and NanofiltrationSiO 2 ) Scaling for Reverse Osmosis , ASTM Designation D

Gabelich, C J; Ishida, K P; Gerringer, F W; Evangelista, R; Kalyan, M; Suffet, I H

2006-01-01T23:59:59.000Z

357

Reduced gravity Rankine cycle system design and optimization study with passive vortex phase separation  

E-Print Network (OSTI)

REDUCED GRAVITY RANKINE CYCLE SYSTEM DESIGN AND OPTIMIZATION STUDY WITH PASSIVE VORTEX PHASE SEPARATION A Thesis by KEVIN ROBERT SUPAK Submitted to the Office of Graduate Studies of Texas A&M University... SEPARATION A Thesis by KEVIN ROBERT SUPAK Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved by: Chair of Committee, Frederick...

Supak, Kevin Robert

2008-10-10T23:59:59.000Z

358

Effects of syngas composition on combustion induced vortex breakdown (CIVB) flashback in a swirl stabilized combustor  

Science Journals Connector (OSTI)

Flame flashback attributed to combustion induced vortex breakdown (CIVB) is a major design challenge for swirl stabilized burner combustors. This paper presents an experimental investigation of combustion induced vortex breakdown (CIVB) flashback propensity for flames yielded from Hydrogen (H2)–Carbon Monoxide (CO) fuel blends and actual synthesized gas (syngas) mixtures. A two-fold experimental approach, consisting of a high definition digital imaging system and a high speed PIV system, was employed. The main emphasis was on the effect of concentration of different constituents in fuel mixtures on flashback limit. In addition, the effect of Swirl Number on flashback propensity was discussed. The percentage of H2 in fuel mixtures played the dominant role when CIVB flashback occurred. For a given air mass flow rate, the mixture containing a higher percentage of H2 underwent flashback at much leaner conditions. Flashback maps for actual syngas fuel compositions showed a distinct behavior when various concentrations of diluents were introduced in the mixture. For the two major diluents tested, carbon dioxide (CO2) and nitrogen dioxide (NO2), CO2 was more dominant. The effect of Swirl Number on the flashback propensity was also tested and showed a decrease with an increase in Swirl Number. The final portion of this paper also provides an analysis of flow field of reacting flames which revealed complex vortex–chemistry interactions leading to vortex breakdown and flashback. Based on the experimental results a parametric model similar to Peclet Number approach was developed employing a flame quenching concept. A value of the quench parameter, Cquench was obtained from the correlation of flow Peclet Number and flame Peclet Number, which was observed to be dominated by the fuel composition rather than Swirl Number.

Bidhan Dam; Gilberto Corona; Mir Hayder; Ahsan Choudhuri

2011-01-01T23:59:59.000Z

359

Aircraft Emissions Deposited in the Stratosphere and Within the Arctic Polar Vortex. Final report  

SciTech Connect

This report describes an analysis of the quantity of emissions (water vapor, NO(x)) projected to be deposited directly within the Arctic polar vortex by projected fleets of Mach 2.4 high speed civil transports (HSCT`s). It also evaluates the amount of emissions from subsonic aircraft which are emitted into the lower stratosphere using aircraft emission inventories developed earlier for May 1990 as representative of the annual average.

Baughcum, S.L.

1996-04-01T23:59:59.000Z

360

Three-Dimensional Nonlinear Lattices: From Oblique Vortices and Octupoles to Discrete Diamonds and Vortex Cubes  

Science Journals Connector (OSTI)

We construct a variety of novel localized topological structures in the 3D discrete nonlinear Schrödinger equation. The states can be created in Bose-Einstein condensates trapped in strong optical lattices and crystals built of microresonators. These new structures, most of which have no counterparts in lower dimensions, range from multipole patterns and diagonal vortices to vortex “cubes” (stack of two quasiplanar vortices) and “diamonds” (formed by two orthogonal vortices).

R. Carretero-González; P. G. Kevrekidis; B. A. Malomed; D. J. Frantzeskakis

2005-05-23T23:59:59.000Z

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

HyCore | Open Energy Information  

Open Energy Info (EERE)

HyCore Jump to: navigation, search Name: HyCore Place: Norway Sector: Hydro, Solar Product: JV between Umicore and Norsk Hydro to manufacture solar-grade silicon. References:...

362

Matrix Acidizing Parallel Core Flooding Apparatus  

E-Print Network (OSTI)

and provide this information to the field. To conduct various experiments, core flooding setups are created. The setup consists of a core holder, accumulator, overburden pump, injection pump, accumulator, pressure sensors, and a back pressure regulator...

Ghosh, Vivek

2013-07-23T23:59:59.000Z

363

Kelvin-Helmholtz instability in a current-vortex sheet at a 3D magnetic null  

SciTech Connect

We report here, for the first time, an observed instability of a Kelvin-Helmholtz nature occurring in a fully three-dimensional (3D) current-vortex sheet at the fan plane of a 3D magnetic null point. The current-vortex layer forms self-consistently in response to foot point driving around the spine lines of the null. The layer first becomes unstable at an intermediate distance from the null point, with the instability being characterized by a rippling of the fan surface and a filamentation of the current density and vorticity in the shear layer. Owing to the 3D geometry of the shear layer, a branching of the current filaments and vortices is observed. The instability results in a mixing of plasma between the two topologically distinct regions of magnetic flux on either side of the fan separatrix surface, as flux is reconnected across this surface. We make a preliminary investigation of the scaling of the system with the dissipation parameters. Our results indicate that the fan plane separatrix surface is an ideal candidate for the formation of current-vortex sheets in complex magnetic fields and, therefore, the enhanced heating and connectivity change associated with the instabilities of such layers.

Wyper, P. F. [School of Mathematics and Statistics, University of Sheffield, Sheffield S3 7RH (United Kingdom); Pontin, D. I. [Division of Mathematics, University of Dundee, Dundee DD1 4HN (United Kingdom)

2013-03-15T23:59:59.000Z

364

Time Reversal in Solids (Linear and Nonlinear Elasticity): Multimedia Resources in Time Reversal  

DOE Data Explorer (OSTI)

Dynamic nonlinear elastic behavior, nonequilibrium dynamics, first observed as a curiosity in earth materials has now been observed in a great variety of solids. The primary manifestations of the behavior are characteristic wave distortion, and slow dynamics, a recovery process to equilibrium that takes place linearly with the logarithm of time, over hours to days after a wave disturbance. The link between the diverse materials that exhibit nonequilibrium dynamics appears to be the presence of soft regions, thought to be 'damage' at many scales, ranging from order 10-9 m to 10-1 m at least. The regions of soft matter may be distributed as in a rock sample, or isolated, as in a sample with a single crack [LANLhttp://www.lanl.gov/orgs/ees/ees11/geophysics/nonlinear/nonlinear.shtml]. The Geophysics Group (EES-11) at Los Alamos National Laboratory has posted two or more multimedia items under each of the titles below to demonstrate aspects of their work: 1) Source Reconstruction Using Time Reversal; 2) Robustness and Efficiency of Time Reversal Acoustics in Solid Media; 3) Audio Example of Time Reversal - Speech Privacy; 4) Crack Imagining with Time Reversal - Experimental Results; 5) Time Reversal of the 2004 (M9.0) Sumatra Earthquake.

365

The SimCore/Alpha Functional Simulator  

Science Journals Connector (OSTI)

We have developed a function-level processor simulator, SimCore/Alpha Functional Simulator Version 2.0 (SimCore Version 2.0), for processor architecture research and processor education. This paper describes the design and implementation of SimCore Version ...

Kenji Kise; Takahiro Katagiri; Hiroki Honda; Toshitsugu Yuba

2004-06-01T23:59:59.000Z

366

Core Competency Worksheets for Significant Cybersecurity Roles  

Energy.gov (U.S. Department of Energy (DOE))

OCIO has developed core competency worksheets for significant cyber roles to assist training personnel, curricula developers, supervisors, etc. with identifying core skills needed to perform their functional roles. Core competencies can be used to develop training objectives for site or organization-specific role-based training.

367

GCFR core thermal-hydralic design  

SciTech Connect

The approach for developing the thermal-hydraulic core assembly designs for the gas-cooled fast reactor (GCFR) is reviewed, and key considerations for improving the core performance at all power and flow conditions are discussed. It is shown how the thermal-hydraulic core assembly designs evolve from evaluations of plant size, material limitations, safety criteria, and structural performance considerations.

Schleuter, G.; Baxi, C.B.; Bennett, F.O.

1980-05-01T23:59:59.000Z

368

Russian techniques for more productive core drilling  

SciTech Connect

This is a short discussion of the trends and technology being used in Russia to increase the production of core drilling. The currently used rigs are given with the plans for improvement in drive methods and to reduce trip time in the recovery of cores. The recommendations by the Russians to improve the core recovery quality and quantity are also given.

Not Available

1984-09-01T23:59:59.000Z

369

DOE CYBER SECURITY EBK: MINIMUM CORE COMPETENCY TRAINING REQUIREMENTS...  

Office of Environmental Management (EM)

DOE CYBER SECURITY EBK: MINIMUM CORE COMPETENCY TRAINING REQUIREMENTS DOE CYBER SECURITY EBK: MINIMUM CORE COMPETENCY TRAINING REQUIREMENTS DOE CYBER SECURITY EBK: CORE COMPETENCY...

370

DOE CYBER SECURITY EBK: CORE COMPETENCY TRAINING REQUIREMENTS...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

CORE COMPETENCY TRAINING REQUIREMENTS: CA DOE CYBER SECURITY EBK: CORE COMPETENCY TRAINING REQUIREMENTS: CA DOE CYBER SECURITY EBK: CORE COMPETENCY TRAINING REQUIREMENTS. Key Cyber...

371

A reverse counterfactual analysis of causation  

E-Print Network (OSTI)

to justly acknowledge. Particular thanks go to: Knut Nygaard, for pizza and weights in Boston; Julian Hendrix for cat-sitting, house-sitting and wife-sitting while I was at Harvard; Richard Lloyd Morgan, for listening; Jackie Solomon and Maria Whelan... , Schaffer 2007. 4Collins, Hall and Paul say that a divide-and-conquer methodology is acceptable, given how tough the analysis of causation is (Collins et al. 2004, 38–39). 1.5. THINKING ABOUT THE REVERSE COUNTERFACTUAL 13 the difference between e occurring...

Broadbent, Alex

2007-11-20T23:59:59.000Z

372

Steady State Thermoelectric Field-Reversed Configurations  

Science Journals Connector (OSTI)

It is shown that the cross-field thermoelectric force of magnetized plasmas can maintain field-reversed configurations against resistive diffusion, resulting in a steady state device attractive for thermonuclear fusion. If a peaked radial temperature profile is maintained, the thermoelectric force is in the opposite direction to the usual resistive friction, thus maintaining the field configuration. The field maintenance is tantamount to dynamo action, operating even in two dimensions. We show that a steady state device can be made by simply heating the O-point: no external electric fields or particle sources are needed. The feasibility of this scheme for fusion is discussed.

A. B. Hassam; R. M. Kulsrud; R. J. Goldston; H. Ji; M. Yamada

1999-10-11T23:59:59.000Z

373

Kinetic Stability of the Field Reversed Configuration  

SciTech Connect

New computational results are presented which advance the understanding of the stability properties of the Field-Reversed Configuration (FRC). The FRC is an innovative confinement approach that offers a unique fusion reactor potential because of its compact and simple geometry, translation properties, and high plasma beta. One of the most important issues is FRC stability with respect to low-n (toroidal mode number) MHD modes. There is a clear discrepancy between the predictions of standard MHD theory that many modes should be unstable on the MHD time scale, and the observed macroscopic resilience of FRCs in experiments.

E.V. Belova; R.C. Davidson; H. Ji; and M. Yamada

2002-07-09T23:59:59.000Z

374

Core Coupling in Nb-99  

E-Print Network (OSTI)

to be good. NUCLEAR REACTIONS, NUCLEAR STRUCTURE '"Mop, 'He), E =40.7 Mev, measured o(8) 99Nb levels deduced S. Calculated levels, 4, n', 8 NNb, particle- core-coupling model. The proton configurations of nuclei in the Zr-Mo region have been the subject... of much experimental interest. ' ' The only information available on ~Nb, however, was obtained by measurement of y decay following 99Zr P decay, ~ and is rather lim- ited. We have studied the levels of "Nb with the Mo(d, 'He) reaction at 40.7-Me...

Bindal, P. K.; Youngblood, David H.

1974-01-01T23:59:59.000Z

375

SoCore Energy | Open Energy Information  

Open Energy Info (EERE)

SoCore Energy SoCore Energy Jump to: navigation, search Name SoCore Energy Place Chicago, Illinois Zip 60601 Sector Solar Product Chicago-based solar installer and mounting solution company that also arranges for solar loans and PPAs. References SoCore Energy[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. SoCore Energy is a company located in Chicago, Illinois . References ↑ "SoCore Energy" Retrieved from "http://en.openei.org/w/index.php?title=SoCore_Energy&oldid=351218" Categories: Clean Energy Organizations Companies Organizations Stubs What links here Related changes Special pages Printable version Permanent link Browse properties About us Disclaimers Energy blogs

376

Global Stability of the Field Reversed Configuration  

SciTech Connect

New computational results are presented which provide a theoretical basis for the stability of the Field Reversed Configuration (FRC). The FRC is a compact toroid with negligible toroidal field in which the plasma is confined by a poloidal magnetic field associated with toroidal diamagnetic current. Although many MHD modes are predicted to be unstable, FRCs have been produced successfully by several formation techniques and show surprising macroscopic resilience. In order to understand this discrepancy, we have developed a new 3D nonlinear hybrid code (kinetic ions and fluid electrons), M3D-B, which is used to study the role of kinetic effects on the n = 1 tilt and higher n modes in the FRC. Our simulations show that there is a reduction in the tilt mode growth rate in the kinetic regime, but no absolute stabilization has been found for s bar less than or approximately equal to 1, where s bar is the approximate number of ion gyroradii between the field null and the separatrix. However, at low values of s bar, the instabilities saturate nonlinearly through a combination of a lengthening of the initial equilibrium and a modification of the ion distribution function. These saturated states persist for many Alfven times, maintaining field reversal.

E.V. Belova; S.C. Jardin; H. Ji; R.M. Kulsrud; W. Park; M. Yamada

2000-11-15T23:59:59.000Z

377

Turbine blade platform film cooling with simulated stator-rotor purge flow with varied seal width and upstream wake with vortex  

E-Print Network (OSTI)

phase locations to model the unsteady wake formed at the trailing edge of the upstream vane. Delta wings were also placed in four positions to create a vortex similar to the passage vortex at the exit of the vane. The film cooling effectiveness...

Blake, Sarah Anne

2009-05-15T23:59:59.000Z

378

Novel 4-Way Refrigerant Reversing Valve for Heat Pumps  

SciTech Connect

This project is nearing completion. Since the last progress report (November, 1999), all experimental tests have been completed. Preliminary analysis shows the refrigerant pressure drops through the reversing valve were reduced by an average of about 60{percent}, when compared to traditional reversing valves. Also, the prototype reversing valve reduced the overall coefficient of performance (COP) by an average of only 0.45{percent}.

Darin W. Nutter

2000-02-17T23:59:59.000Z

379

Core Capabilities | Argonne National Laboratory  

NLE Websites -- All DOE Office Websites (Extended Search)

The Advanced Photon Source is one of the brightest sources of X-rays in the The Advanced Photon Source is one of the brightest sources of X-rays in the Western Hemisphere. Photons are accelerated to over 99% of the speed of light around its ring, which is the size of a baseball stadium. To view a larger version of the image, click on it. The Center for Nanoscale Materials at Argonne is a premier user facility, providing expertise, instruments, and infrastructure for interdisciplinary nanoscience and nanotechnology research. To view a larger version of the image, click on it. Core Capabilities Argonne's vision is to lead the world in discovery science and engineering that provides technical solutions to the grand challenges of our time. Argonne's vision is to lead the world in discovery science and engineering that provides technical solutions to the grand challenges of our time:

380

Test report -- Prototype core sampler  

SciTech Connect

The purpose of this test is to determine the adequacy of the prototype sampler, provided to Westinghouse Hanford Company (WHC) by DOE-RL. The sampler was fabricated for DOE-RL by the Concord Company by request of DOE-RL. This prototype sampler was introduced as a technology that can be easily deployed (similar to the current auger system) and will reliably collect representative samples. The sampler is similar to the Universal Sampler i.e., smooth core barrel and piston with an O-ring seal, but lacks a rotary valve near the throat of the sampler. This makes the sampler inappropriate for liquid sampling, but reduces the outside diameter of the sampler considerably, which should improve sample recovery. Recovery testing was performed with the supplied sampler in three different consistencies of Kaolin sludge simulants.

Linschooten, C.G.

1995-01-17T23:59:59.000Z

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Nuclear core and fuel assemblies  

DOE Patents (OSTI)

A fast flux nuclear core of a plurality of rodded, open-lattice assemblies having a rod pattern rotated relative to a rod support structure pattern. Elongated fuel rods are oriented on a triangular array and laterally supported by grid structures positioned along the length of the assembly. Initial inter-assembly contact is through strongbacks at the corners of the support pattern and peripheral fuel rods between adjacent assemblies are nested so as to maintain a triangular pitch across a clearance gap between the other portions of adjacent assemblies. The rod pattern is rotated relative to the strongback support pattern by an angle .alpha. equal to sin .sup.-1 (p/2c), where p is the intra-assembly rod pitch and c is the center-to-center spacing among adjacent assemblies.

Downs, Robert E. (Monroeville, PA)

1981-01-01T23:59:59.000Z

382

WAVE-VORTEX MODE COUPLING IN ASTROPHYSICAL ACCRETION DISKS UNDER COMBINED RADIAL AND VERTICAL STRATIFICATION  

SciTech Connect

We examine accretion disk flow under combined radial and vertical stratification utilizing a local Cartesian (or ''shearing box'') approximation. We investigate both axisymmetric and nonaxisymmetric disturbances with the Boussinesq approximation. Under axisymmetric disturbances, a new dispersion relation is derived. It reduces to the Solberg-Hoieland criterion in the case without vertical stratification. It shows that, asymptotically, stable radial and vertical stratification cannot induce any linear instability; Keplerian flow is accordingly stable. Previous investigations strongly suggest that the so-called bypass concept of turbulence (i.e., that fine-tuned disturbances of any inviscid smooth shear flow can reach arbitrarily large transient growth) can also be applied to Keplerian disks. We present an analysis of this process for three-dimensional plane-wave disturbances comoving with the shear flow of a general rotating shear flow under combined stable radial and vertical rotation. We demonstrate that large transient growth occurs for K{sub 2}/k{sub 1} >> 1 and k{sub 3} = 0 or k{sub 1} {approx} k{sub 3}, where k{sub 1}, K{sub 2}, and k{sub 3} are the azimuthal, radial, and vertical components of the initial wave vector, respectively. By using a generalized ''wave-vortex'' decomposition of the disturbance, we show that the large transient energy growth in a Keplerian disk is mainly generated by the transient dynamics of the vortex mode. The analysis of the power spectrum of total (kinetic+potential) energy in the azimuthal or vertical directions shows that the contribution coming from the vortex mode is dominant at large scales, while the contribution coming from the wave mode is important at small scales. These findings may be confirmed by appropriate numerical simulations in the high Reynolds number regime.

Salhi, A. [Departement de Physique, Faculte des Sciences de Tunis, 1060 Tunis (Tunisia); Lehner, T. [LUTH, UMR 8102 CNRS, Observatoire de Paris-Meudon, 5 place de Janssen, F-92195 Meudon (France); Godeferd, F.; Cambon, C. [Laboratoire de Mecanique des Fluides et d'Acoustique, Ecole Centrale de Lyon, Universite de Lyon, UMR 5509, CNRS, INSA, UCB, F-69134 Ecully Cedex (France)

2013-07-10T23:59:59.000Z

383

Non-equilibrium coherent vortex states and subharmonic giant Shapiro steps in Josephson junction arrays  

E-Print Network (OSTI)

This is a review of recent work on the dynamic response of Josephson junction arrays driven by dc and ac currents. The arrays are modeled by the resistively shunted Josephson junction model, appropriate for proximity effect junctions, including self-induced magnetic fields as well as disorder. The relevance of the self-induced fields is measured as a function of a parameter $\\kappa=\\lambda_L/a$, with $\\lambda_L$ the London penetration depth of the arrays, and $a$ the lattice spacing. The transition from Type II ($\\kappa>1$) to Type I ($\\kappa <1$) behavior is studied in detail. We compare the results for models with self, self+nearest-neighbor, and full inductance matrices. In the $\\kappa=\\infty$ limit, we find that when the initial state has at least one vortex-antivortex pair, after a characteristic transient time these vortices unbind and {\\it radiate} other vortices. These radiated vortices settle into a parity-broken, time-periodic, {\\em axisymmetric coherent vortex state} (ACVS), characterized by alternate rows of positive and negative vortices lying along a tilted axis. The ACVS produces subharmonic steps in the current voltage (IV) characteristics, typical of giant Shapiro steps. For finite $\\kappa$ we find that the IV's show subharmonic giant Shapiro steps, even at zero external magnetic field. We find that these subharmonic steps are produced by a whole family of coherent vortex oscillating patterns, with their structure changing as a function of $\\kappa$. In general, we find that these patterns are due to a break down of translational invariance produced, for example, by disorder or antisymmetric edge-fields. The zero field case results are in good qualitative agreement with experiments

Daniel Domínguez; Jorge V. José

1994-07-11T23:59:59.000Z

384

Over Core Stress | Open Energy Information  

Open Energy Info (EERE)

Over Core Stress Over Core Stress Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Over Core Stress Details Activities (1) Areas (1) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Rock Lab Analysis Parent Exploration Technique: Rock Lab Analysis Information Provided by Technique Lithology: Stratigraphic/Structural: Hydrological: Thermal: Dictionary.png Over Core Stress: No definition has been provided for this term. Add a Definition Related Techniques Rock Lab Analysis Core Analysis Cuttings Analysis Isotopic Analysis- Rock Over Core Stress Paleomagnetic Measurements Petrography Analysis Rock Density X-Ray Diffraction (XRD) X-Ray Fluorescence (XRF) References Page Area Activity Start Date Activity End Date Reference Material

385

Dynamic simulation of a reverse Brayton refrigerator  

SciTech Connect

A test refrigerator based on the modified Reverse Brayton cycle has been developed in the Chinese Academy of Sciences recently. To study the behaviors of this test refrigerator, a dynamic simulation has been carried out. The numerical model comprises the typical components of the test refrigerator: compressor, valves, heat exchangers, expander and heater. This simulator is based on the oriented-object approach and each component is represented by a set of differential and algebraic equations. The control system of the test refrigerator is also simulated, which can be used to optimize the control strategies. This paper describes all the models and shows the simulation results. Comparisons between simulation results and experimental data are also presented. Experimental validation on the test refrigerator gives satisfactory results.

Peng, N.; Xiong, L. Y.; Dong, B.; Liu, L. Q. [State Key Laboratory of Technologies in Space Cryogenic Propellants, Technical Institute of Physics and Chemistry, CAS, Beijing, 100190 (China); Lei, L. L.; Tang, J. C. [State Key Laboratory of Technologies in Space Cryogenic Propellants, Technical Institute of Physics and Chemistry, CAS, Beijing, 100190 China and Graduate University of Chinese Academy of Sciences, Beijing, 100190 (China)

2014-01-29T23:59:59.000Z

386

Direct observation of time reversal violation  

SciTech Connect

A direct evidence for Time Reversal Violation (TRV) means an experiment that, considered by itself, clearly shows TRV independent of, and unconnected to, the results for CP Violation. No existing result before the recent BABAR experiment with entangled neutral B mesons had demonstrated TRV in this sense. There is a unique opportunity for a search of TRV with unstable particles thanks to the Einstein-Podolsky-Rosen (EPR) Entanglement between the two neutral mesons in B, and PHI, Factories. The two quantum effects of the first decay as a filtering measurement and the transfer of information to the still living partner allow performing a genuine TRV asymmetry with the exchange of 'in' and 'out' states. With four independent TRV asymmetries, BABAR observes a large deviation of T-invariance with a statistical significance of 14 standard deviations, far more than needed to declare the result as a discovery. This is the first direct observation of TRV in the time evolution of any system.

Bernabeu, J. [Department of Theoretical Physics, University of Valencia, and IFIC, Joint Centre Univ. Valencia-CSIC (Spain)

2013-06-12T23:59:59.000Z

387

Control of magnetization reversal in oriented strontium ferrite thin films  

SciTech Connect

Oriented Strontium Ferrite films with the c axis orientation were deposited with varying oxygen partial pressure on Al{sub 2}O{sub 3}(0001) substrate using Pulsed Laser Deposition technique. The angle dependent magnetic hysteresis, remanent coercivity, and temperature dependent coercivity had been employed to understand the magnetization reversal of these films. It was found that the Strontium Ferrite thin film grown at lower (higher) oxygen partial pressure shows Stoner-Wohlfarth type (Kondorsky like) reversal. The relative importance of pinning and nucleation processes during magnetization reversal is used to explain the type of the magnetization reversal with different oxygen partial pressure during growth.

Roy, Debangsu, E-mail: debangsu@physics.iisc.ernet.in; Anil Kumar, P. S. [Department of Physics, Indian Institute of Science, Bangalore 560012 (India)

2014-02-21T23:59:59.000Z

388

Ethanol separation from molasses based fermentation broth by reverse osmosis  

Science Journals Connector (OSTI)

Irradiated styrene-grafted cellulose acetate membrane was used for the separation of ethanol by reverse osmosis. Ethanol separation from molasses based fermentation broth...

J. P. Choudhury; P. Ghosh; B. K. Guha

1986-10-01T23:59:59.000Z

389

Molecular dynamics simulations of osmosis and reverse osmosis in solutions  

Science Journals Connector (OSTI)

Computer simulation studies using the method of molecular dynamics have been carried out to investigate osmosis and reverse osmosis in solutions separated by semi-permeable membranes....

S. Murad

1996-01-01T23:59:59.000Z

390

Structures of cellulose acetate membranes for reverse osmosis  

Science Journals Connector (OSTI)

Studies under the scanning electron microscope have shown that the cellulose acetate membranes used for reverse osmosis are high-molecular-weight condensation structures of...

I. N. Vlodavets; G. Z. Nefedova…

1977-01-01T23:59:59.000Z

391

Reversible mechanism for spin crossover in transition-metal cyanides  

E-Print Network (OSTI)

We report the mechanisms for reversible and repeatable spin transition in a Prussian blue analog crystal, KCo[Fe(CN)[subscript 6

Kabir, Mohammad Mukul

392

Photochromic Metal-Organic Frameworks: Reversible Control of...  

NLE Websites -- All DOE Office Websites (Extended Search)

Photochromic Metal-Organic Frameworks: Reversible Control of Singlet Oxygen Generation Previous Next List Jihye Park, Dawei Feng, Shuai Yuan and Hong-Cai Zhou, Angew. Chem. Int....

393

Development of Reversible Fuel Cell Systems at Proton Energy...  

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

at Proton Energy Presentation by Everett Anderson, PROTON ON SITE, at the NREL Reversible Fuel Cells Workshop, April 19, 2011 revfcwkshpanderson.pdf More Documents &...

394

Reverse audio engineering for active listening and other applications.  

E-Print Network (OSTI)

??This work deals with the problem of reverse audio engineering for active listening. The format under consideration corresponds to the audio CD. The musical content… (more)

Gorlow, Stasnislaw

2013-01-01T23:59:59.000Z

395

Interconversion of dark soliton and Josephson vortex in a quasi-1D long Bose Josephson junction  

E-Print Network (OSTI)

Dark soliton (DS) and Josephson vortex (JV) in quasi-1D long Bose Josephson junction (BJJ) can be interconverted by tuning Josephson coupling. Rates of the interconversion as well as of the thermally activated phase-slip effect, resulting in the JV switching its vorticity, have been evaluated. The role of quantum phase-slip in creating superposition of JVs with opposite vorticities as a qubit is discussed as well. Utilization of the JV for controlled and coherent transfer of atomic Bose-Einstein condensate (BEC) is suggested.

V. M. Kaurov; A. B. Kuklov

2004-06-15T23:59:59.000Z

396

Vortex states in a binary mixture of Bose-Einstein condensates  

Science Journals Connector (OSTI)

The vortex configurations in the Bose-Einstein condensate of a mixture of two different spin states |F=1,mf=-1? and |2,1? of 87Rb atoms corresponding to the recent experiments by Matthews et al. [Phys. Rev. Lett. 83, 2498 (1999)] are considered in the framework of the Thomas-Fermi approximation as functions of N2/N1, where N1 is the number of atoms in the state |1,-1? and N2 in the state |2,1?. Ranges of this ratio are determined within which the various configurations of the binary condensate are stable.

S. T. Chui; V. N. Ryzhov; E. E. Tareyeva

2001-01-11T23:59:59.000Z

397

Energy-efficient reverse osmosis desalination process  

Science Journals Connector (OSTI)

Abstract A novel energy-efficient reverse osmosis (EERO) process is proposed for which the retentate from single-stage reverse osmosis (SSRO) serves as the feed to a countercurrent membrane cascade with recycle (CMCR). The 3-stage EERO process employs two, whereas the 4-stage EERO process employs three stages in the CMCR. The EERO process is advantageous because of four features: (i) coupling SSRO with a CMCR; (ii) countercurrent retentate and permeate flow; (iii) permeate recycling; and (iv) retentate self-recycling owing to the use of one or more nanofiltration stages. The EERO process was compared to conventional SSRO for both processes operating at the thermodynamic limit and employing an energy-recovery device. For the same overall recovery the osmotic pressure differential is reduced by 33% and 50% relative to SSRO for the 3- and 4-stage ERRO processes, respectively. There is a critical recovery above which the EERO process also can reduce the specific energy consumption (SEC) relative to SSRO for the same recovery. For a typical seawater feed of 35 g/L the 3-stage EERO process can achieve a 75% recovery at a net SEC of 2.746 kWh/m3, an 11.0% reduction in the SEC relative to SSRO for the same recovery. The 4-stage EERO process can achieve a 75% recovery at the same net SEC as SSRO (3.086 kWh/m3). Accounting for the additional membrane area required for the EERO process increases its cost relative to that for SSRO by at most 8%. An additional benefit of the EERO process relative to SSRO is the highly concentrated retentate that reduces the brine disposal volume or can be used to greatly increase the draw potential to harvest its osmotic potential energy via the pressure-retarded osmosis process.

Tzyy Haur Chong; Siew-Leng Loo; William B. Krantz

2015-01-01T23:59:59.000Z

398

Large Pitch Hollow Core Honeycomb Fiber  

Science Journals Connector (OSTI)

A new kind of hollow core photonic crystal fiber (HC-PCF) for broadband guidance is introduced. Structural and optical properties of a fabricated example are detailed.

Beaudou, Benoît; Couny, François; Benabid, Fetah; Roberts, Peter John

399

PULSATING REVERSE DETONATION MODELS OF TYPE Ia SUPERNOVAE. I. DETONATION IGNITION  

SciTech Connect

Observational evidences point to a common explosion mechanism of Type Ia supernovae based on a delayed detonation of a white dwarf (WD). Although several scenarios have been proposed and explored by means of one, two, and three-dimensional simulations, the key point still is the understanding of the conditions under which a stable detonation can form in a destabilized WD. One of the possibilities that have been invoked is that an inefficient deflagration leads to the pulsation of a Chandrasekhar-mass WD, followed by formation of an accretion shock around a carbon-oxygen rich core. The accretion shock confines the core and transforms kinetic energy from the collapsing halo into thermal energy of the core, until an inward moving detonation is formed. This chain of events has been termed Pulsating Reverse Detonation (PRD). In this work we explore the robustness of the detonation ignition for different PRD models characterized by the amount of mass burned during the deflagration phase, M {sub defl}. The evolution of the WD up to the formation of the accretion shock has been followed with a three-dimensional hydrodynamical code with nuclear reactions turned off. We found that detonation conditions are achieved for a wide range of M {sub defl}. However, if the nuclear energy released during the deflagration phase is close to the WD binding energy ({approx}0.46 x 10{sup 51} erg {yields} M {sub defl} {approx} 0.30 M {sub sun}) the accretion shock cannot heat and confine the core efficiently and detonation conditions are not robustly achieved.

Bravo, Eduardo; GarcIa-Senz, Domingo [Department de FIsica i Enginyeria Nuclear, Universitat Politecnica de Catalunya, Diagonal 647, 08028 Barcelona (Spain)], E-mail: eduardo.bravo@upc.edu, E-mail: domingo.garcia@upc.edu

2009-04-20T23:59:59.000Z

400

Femtosecond laser fabrication of micro and nano-disks in single layer graphene using vortex Bessel beams  

SciTech Connect

We report the fabrication of micro and nano-disks in single layer chemical vapor deposition graphene on glass substrate using femtosecond laser ablation with vortex Bessel beams. The fabricated graphene disks with diameters ranging from 650?nm to 4??m were characterized by spatially resolved micro-Raman spectroscopy. The variation of ablation threshold was investigated as a function of the number of pulses showing an incubation effect. A very high degree of size control of the fabricated graphene disks is enabled using a sequence of femtosecond pulses with different vortex orders.

Wetzel, Benjamin, E-mail: benjamin.wetzel@femto-st.fr; Xie, Chen; Lacourt, Pierre-Ambroise; Dudley, John M.; Courvoisier, Francois [Département d'Optique P.M. Duffieux, Institut FEMTO-ST, UMR–6174 CNRS, Université de Franche-Comté, 25030 Besançon (France)] [Département d'Optique P.M. Duffieux, Institut FEMTO-ST, UMR–6174 CNRS, Université de Franche-Comté, 25030 Besançon (France)

2013-12-09T23:59:59.000Z

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Axisymmetric-coherent-vortex states in current-driven Josephson-junction arrays  

SciTech Connect

We present results from an extensive analysis of the dynamic response of Josephson-junction arrays driven by external currents of the form [ital I]=[ital I][sub dc]+[ital I][sub ac]sin(2[pi][nu][ital t]). The dynamics is given by the resistively shunted Josephson-junction model with Johnson noise. We find a stationary [ital axisymmetric][minus][ital coherent][minus][ital vortex] [ital state] (ACVS) away from equilibrium and above a minimum lattice size ([similar to]20[times]20) whenever the initial state has at least one antivortex and a vortex. The ACVS is characterized by tilted rows of oscillating positive and negative vortices, produced by the combined effect of the driving current plus the collective coupling of the nonlinear Josephson oscillators. The ACVS is manifested in the current-voltage characteristics as giant half-integer Shapiro steps, leading to period-two resonances in the spectral function. The stability and properties of the ACVS are studied as a function of frequency, temperature, disorder, edge magnetic fields, and lattice sizes. It is found that the ACVS is a very robust two-dimensional dynamical state that is produced under very diverse circumstances. A connection between the ACVS and half-integer steps seen in proximity effect arrays in zero field is also discussed.

Dominguez, D.; Jose, J.V. (Physics Department, Northeastern University, Boston, Massachusetts 02115 (United States))

1993-11-01T23:59:59.000Z

402

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

E-Print Network (OSTI)

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 $\\pm\\frac{2\\pi n}{e}$ 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 value of Higgs boson mass $0\\leq M_H^2\\leq 80$ at Weinberg angle $\\theta_W=\\frac{\\pi}{4}$.

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

2014-08-20T23:59:59.000Z

403

Tests of time reversal in neutron?nucleus scattering  

Science Journals Connector (OSTI)

Experiments to test time?reversal invariance are discussed. The experiments are based on observables constructed from the momentum and spin vectors of epithermal neutrons and from the spin of an aligned or polarized target. It is shown that the proposed tests are detailed balance tests of time?reversal invariance. The status of the experiments is briefly reviewed.

J. David Bowman

1988-01-01T23:59:59.000Z

404

Reducing current reversal time in electric motor control  

DOE Patents (OSTI)

The time required to reverse current flow in an electric motor is reduced by exploiting inductive current that persists in the motor when power is temporarily removed. Energy associated with this inductive current is used to initiate reverse current flow in the motor.

Bredemann, Michael V

2014-11-04T23:59:59.000Z

405

Hydrogenation of Magnesium Nickel Boride for Reversible Hydrogen Storage  

Science Journals Connector (OSTI)

Hydrogenation of Magnesium Nickel Boride for Reversible Hydrogen Storage ... Use of hydrogen for transportation applications requires materials that not only store hydrogen at high density but that can operate reversibly at temperatures and pressures below approximately 100 °C and 10 bar, respectively. ... This composition is based on assuming the following complete hydrogenation reaction:which stores 2.6 wt % hydrogen. ...

Wen Li; John J. Vajo; Robert W. Cumberland; Ping Liu; Son-Jong Hwang; Chul Kim; Robert C. Bowman, Jr.

2009-11-06T23:59:59.000Z

406

Reverse Ecology: From Systems to Environments and Back  

E-Print Network (OSTI)

Chapter 15 Reverse Ecology: From Systems to Environments and Back Roie Levy and Elhanan Borenstein the environments in which they evolved and are adapted to. Re- verse Ecology--an emerging new frontier's ecology. The Reverse Ecology framework facilitates the translation of high-throughput genomic data

Borenstein, Elhanan

407

Origin of the Core Francis Nimmo  

E-Print Network (OSTI)

Origin of the Core Francis Nimmo Dept. Earth Sciences, University of California, Santa Cruz F. Nimmo, Dept. Earth Sciences, University of California, Santa Cruz, CA 95064, USA (fnimmo@es.ucsc.edu), tel. 831-459-1783, fax. 831-459-3074 1 #12;Origin of the Core All major bodies of the inner solar

Nimmo, Francis

408

Idealized Test Cases for Dynamical Core Experiments  

E-Print Network (OSTI)

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

Jablonowski, Christiane

409

Experto Universitario Java Sesin 1: Spring core  

E-Print Network (OSTI)

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

Escolano, Francisco

410

Module Handbook Core Univ. of Oldenburg  

E-Print Network (OSTI)

· Mechanical and Electrical Systems of the WEC Content: Energy conversion process in Wind Turbines · Wind/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

Habel, Annegret

411

UNL Core for Applied Genomics and Ecology  

E-Print Network (OSTI)

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

Farritor, Shane

412

Synthesis of the Optimal 4-bit Reversible Circuits  

E-Print Network (OSTI)

Optimal synthesis of reversible functions is a non-trivial problem. One of the major limiting factors in computing such circuits is the sheer number of reversible functions. Even restricting synthesis to 4-bit reversible functions results in a huge search space (16!~2^44 functions). The output of such a search alone, counting only the space required to list Toffoli gates for every function, would require over 100 terabytes of storage. In this paper, we present an algorithm that synthesizes an optimal circuit for any 4-bit reversible specification. We employ several techniques to make the problem tractable. We report results from several experiments, including synthesis of random 4-bit permutations, optimal synthesis of all 4-bit linear reversible circuits, synthesis of existing benchmark functions, and distribution of optimal circuits. Our results have important implications for the design and optimization of quantum circuits, testing circuit synthesis heuristics, and performing experiments in the area of quantum information processing.

Oleg Golubitsky; Sean M. Falconer; Dmitri Maslov

2010-03-09T23:59:59.000Z

413

Linear multistep methods for integrating reversible differential equations  

E-Print Network (OSTI)

This paper studies multistep methods for the integration of reversible dynamical systems, with particular emphasis on the planar Kepler problem. It has previously been shown by Cano & Sanz-Serna that reversible linear multisteps for first-order differential equations are generally unstable. Here, we report on a subset of these methods -- the zero-growth methods -- that evade these instabilities. We provide an algorithm for identifying these rare methods. We find and study all zero-growth, reversible multisteps with six or fewer steps. This select group includes two well-known second-order multisteps (the trapezoidal and explicit midpoint methods), as well as three new fourth-order multisteps -- one of which is explicit. Variable timesteps can be readily implemented without spoiling the reversibility. Tests on Keplerian orbits show that these new reversible multisteps work well on orbits with low or moderate eccentricity, although at least 100 steps/radian are required for stability.

Wyn Evans; Scott Tremaine

1999-06-24T23:59:59.000Z

414

Plant experience with temporary reverse osmosis makeup water systems  

SciTech Connect

Pacific Gas and Electric (PG and E) Company's Diablo Canyon Power Plant (DCPP), which is located on California's central coast, has access to three sources of raw water: creek water, well water, and seawater. Creek and well water are DCPP's primary sources of raw water; however, because their supply is limited, these sources are supplemented with seawater. The purpose of this paper is to discuss the temporary, rental, reverse osmosis systems used by PG and E to process DCPP's raw water into water suitable for plant makeup. This paper addresses the following issues: the selection of reverse osmosis over alternative water processing technologies; the decision to use vendor-operated temporary, rental, reverse osmosis equipment versus permanent PG and E-owned and -operated equipment; the performance of DCPP's rental reverse osmosis systems; and, the lessons learned from DCPP's reverse osmosis system rental experience that might be useful to other plants considering renting similar equipment.

Polidoroff, C.

1986-01-01T23:59:59.000Z

415

Core File Settings | Argonne Leadership Computing Facility  

NLE Websites -- All DOE Office Websites (Extended Search)

Core File Settings Core File Settings The following environment variables control core file creation and contents. Specify regular (non-script) jobs using the qsub argument --env (Note: two dashes). Specify script jobs (--mode script) using the --envs (Note: two dashes) or --exp_env (Note: two dashes) options of runjob. For additional information about setting environment variables in your job, visit http://www.alcf.anl.gov/user-guides/running-jobs#environment-variables. Generation The following environment variables control conditions of core file generation and naming: BG_COREDUMPONEXIT=1 Creates a core file when the application exits. This is useful when the application performed an exit() operation and the cause and location of the exit() is not known. BG_COREDUMPONERROR=1

416

BIMETALLIC LITHIUM BOROHYDRIDES TOWARD REVERSIBLE HYDROGEN STORAGE  

SciTech Connect

Borohydrides such as LiBH{sub 4} have been studied as candidates for hydrogen storage because of their high hydrogen contents (18.4 wt% for LiBH{sub 4}). Limited success has been made in reducing the dehydrogenation temperature by adding reactants such as metals, metal oxides and metal halides. However, full rehydrogenation has not been realized because of multi-step decomposition processes and the stable intermediate species produced. It is suggested that adding second cation in LiBH{sub 4} may reduce the binding energy of B-H. The second cation may also provide the pathway for full rehydrogenation. In this work, several bimetallic borohydrides were synthesized using wet chemistry, high pressure reactive ball milling and sintering processes. The investigation found that the thermodynamic stability was reduced, but the full rehydrogenation is still a challenge. Although our experiments show the partial reversibility of the bimetallic borohydrides, it was not sustainable during dehydriding-rehydriding cycles because of the accumulation of hydrogen inert species.

Au, M.

2010-10-21T23:59:59.000Z

417

Liquid suspensions of reversible metal hydrides  

DOE Patents (OSTI)

The reversibility of the process M + x/2 H/sub 2/ ..-->.. MH/sub x/, where M is a metal hydride former that forms a hydride MH/sub x/ in the presence of H/sub 2/, generally used to store and recall H/sub 2/, is found to proceed under a liquid, thereby to reduce contamination, provide better temperature control and provide in situ mobility of the reactants. Thus, a slurry of particles of a metal hydride former with an inert solvent is subjected to temperature and pressure controlled atmosphere containing H/sub 2/, to store hydrogen (at high pressures) and to release (at low pressures) previously stored hydrogen. The direction of the flow of the H/sub 2/ through the liquid is dependent upon the H/sub 2/ pressure in the gas phase at a given temperature. When the former is above the equilibrium absorption pressure of the respective hydride the reaction proceeds to the right, i.e., the metal hydride is formed and hydrogen is stored in the solid particle. When the H/sub 2/ pressure in the gas phase is below the equilibrium dissociation pressure of the respective hydride the reaction proceeds to the left, the metal hydride is decomposed and hydrogen is released into the gas phase.

Reilly, J.J.; Grohse, E.W.; Winsche, W.E.

1983-12-08T23:59:59.000Z

418

POLAR FIELD REVERSAL OBSERVATIONS WITH HINODE  

SciTech Connect

We have been monitoring yearly variation in the Sun's polar magnetic fields with the Solar Optical Telescope aboard Hinode to record their evolution and expected reversal near the solar maximum. All magnetic patches in the magnetic flux maps are automatically identified to obtain the number density and magnetic flux density as a function of the total magnetic flux per patch. The detected magnetic flux per patch ranges over four orders of magnitude (10{sup 15}-10{sup 20} Mx). The higher end of the magnetic flux in the polar regions is about one order of magnitude larger than that of the quiet Sun, and nearly that of pores. Almost all large patches ({>=}10{sup 18} Mx) have the same polarity, while smaller patches have a fair balance of both polarities. The polarity of the polar region as a whole is consequently determined only by the large magnetic concentrations. A clear decrease in the net flux of the polar region is detected in the slow rising phase of the current solar cycle. The decrease is more rapid in the north polar region than in the south. The decrease in the net flux is caused by a decrease in the number and size of the large flux concentrations as well as the appearance of patches with opposite polarity at lower latitudes. In contrast, we do not see temporal change in the magnetic flux associated with the smaller patches (<10{sup 18} Mx) and that of the horizontal magnetic fields during the years 2008-2012.

Shiota, D. [Advanced Science Institute, RIKEN (Institute of Physics and Chemical Research), Wako, Saitama 351-0198 (Japan); Tsuneta, S.; Shimojo, M.; Orozco Suarez, D.; Ishikawa, R. [National Astronomical Observatory of Japan (NAOJ), Mitaka, Tokyo 181-8588 (Japan); Sako, N., E-mail: shiota@riken.jp [Department of Astronomical Science, The Graduate University for Advanced Studies, Mitaka, Tokyo 181-8588 (Japan)

2012-07-10T23:59:59.000Z

419

Durability Evaluation of Reversible Solid Oxide Cells  

SciTech Connect

An experimental investigation on the performance and durability of single solid oxide cells (SOCs) is under way at the Idaho National Laboratory. Reversible operation of SOCs includes electricity generation in the fuel cell mode and hydrogen generation in the electrolysis mode. Degradation is a more significant issue when operating SOCs in the electrolysis mode. In order to understand and mitigate the degradation issues in high temperature electrolysis, single SOCs with different configurations from several manufacturers have been evaluated for initial performance and long-term durability. A new test apparatus for single cell and small stack tests has been developed for this purpose. Cells were obtained from four industrial partners. Cells from Ceramatec Inc. and Materials and Systems Research Inc. (MSRI) showed improved durability in electrolysis mode compared to previous stack tests. Cells from Saint Gobain Advanced Materials Inc. (St. Gobain) and SOFCPower Inc. demonstrated stable performance in the fuel cell mode, but rapid degradation in the electrolysis mode, especially at high current density. Electrolyte-electrode delamination was found to have a significant impact on degradation in some cases. Enhanced bonding between electrolyte and electrode and modification of the electrode microstructure helped to mitigate degradation. Polarization scans and AC impedance measurements were performed during the tests to characterize cell performance and degradation.

Xiaoyu Zhang; James E. O'Brien; Robert C. O'Brien; Gregory K. Housley

2013-11-01T23:59:59.000Z

420

Quantum Dissociation of a Vortex-Antivortex Pair in a Long Josephson Junction M.V. Fistul,1  

E-Print Network (OSTI)

Quantum Dissociation of a Vortex-Antivortex Pair in a Long Josephson Junction M.V. Fistul,1 A VAV pair manifests itself in a switching of the Josephson junction from the superconducting biased single Josephson junctions (JJs), various SQUIDs, and small Josephson junction arrays, contain

Wallraff, Andreas

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to obtain the most current and comprehensive results.


421

Tracking Waves and Vortex Nucleation in Excitable Systems with Anomalous Dispersion N. Manz, C.T. Hamik, and O. Steinbock  

E-Print Network (OSTI)

Tracking Waves and Vortex Nucleation in Excitable Systems with Anomalous Dispersion N. Manz, C obtained from a chemical reaction-diffusion system in which wave propagation is limited to a finite band of wavelengths and in which no solitary pulses exist. Wave patterns increase their size through repeated

Steinbock, Oliver

422

Quantum Hasimoto transformation and nonlinear waves on a superfluid vortex filament under the quantum local induction approximation  

E-Print Network (OSTI)

The Hasimoto transformation between the classical LIA (local induction approximation, a model approximating the motion of a thin vortex filament) and the nonlinear Schr\\"odinger equation (NLS) has proven very useful in the past, since it allows one to construct new solutions to the LIA once a solution to the NLS is known. In the present paper, the quantum form of the LIA (which includes mutual friction effects) is put into correspondence with a type of complex nonlinear dispersive partial differential equation (PDE) with cubic nonlinearity (similar in form to a Ginsburg-Landau equation, with additional nonlinear terms). Transforming the quantum LIA in such a way enables one to obtain quantum vortex filament solutions once solutions to this dispersive PDE are known. From our quantum Hasimoto transformation, we determine the form and behavior of Stokes waves and a standing 1-soliton solution under normal and binormal friction effects. The soliton solution on a quantum vortex filament is a natural generalization of the classical 1-soliton solution constructed mathematically by Hasimoto (which motivated subsequent real-world experiments). The quantum Hasimoto transformation is useful when normal fluid velocity is relatively weak, so for the case where the normal fluid velocity is dominant we resort to other approaches. We consider the dynamics of the tangent vector to the vortex filament directly from the quantum LIA, and this approach, while less elegant than the quantum Hasimoto transformation, enables us to study waves primarily driven by the normal fluid velocity.

Robert A. Van Gorder

2014-11-19T23:59:59.000Z

423

Energy Losses Due to Vortex Shedding from the Lower Edge of a Vertical Plate Attacked by Surface Waves  

Science Journals Connector (OSTI)

...Vertical Plate Attacked by Surface Waves M. Stiassnie E. Naheer Irina Boguslavsky...The ratio between the flux of the energy taken out by the vortex generation process , and the incoming wave energy flux , is shown to be given by where...

1984-01-01T23:59:59.000Z

424

A comparison of ROChem reverse osmosis and spiral wound reverse osmosis membrane modules  

SciTech Connect

Testing of the ROChem Disc Tube[reg sign] reverse osmosis (RO) module's performance on biologically active feed waters has been completed. Both the ROChem module (using Filmtec standard-rejection seawater membranes) and the Filmtec spiral-wound membrane module (using Filmtec high-rejection seawater membranes) were tested with stimulant solutions containing typical bacteria and metal hydroxide levels found in the F/H Effluent Treatment Facility (ETF) influent. Results indicate that the ROChem module gave superior performance over the spiral-wound module. Water flux losses were reduced by over 30% for water recoveries above 40%.

Siler, J.L.

1992-01-31T23:59:59.000Z

425

A comparison of ROChem reverse osmosis and spiral wound reverse osmosis membrane modules  

SciTech Connect

Testing of the ROChem Disc Tube{reg_sign} reverse osmosis (RO) module`s performance on biologically active feed waters has been completed. Both the ROChem module (using Filmtec standard-rejection seawater membranes) and the Filmtec spiral-wound membrane module (using Filmtec high-rejection seawater membranes) were tested with stimulant solutions containing typical bacteria and metal hydroxide levels found in the F/H Effluent Treatment Facility (ETF) influent. Results indicate that the ROChem module gave superior performance over the spiral-wound module. Water flux losses were reduced by over 30% for water recoveries above 40%.

Siler, J.L.

1992-01-31T23:59:59.000Z

426

An experimental investigation of the rolling moment on a flat plate in the presence of a free vortex of known strength  

E-Print Network (OSTI)

not affect their vertical or lateral positioning. The vortex probe assembly is shown in Figure 2. A comparison of the free-stream velocities obtained from the vortex probe assembly and a standard pitot-static tube revealed a difference of less than one...AN EXPERIMENTAL 1NVES1'IGATION OF THE ROLLING MOMENT ON A ILAT PLATE IN THE ?RESENCE OP A FREE VORTEX OF KNOWN STRENGTH A Thesis by MAURICE VERNE VAN DUSEN, JR. Submitted to the Graduate College of Teras A&M University in partial fulfillment...

Van Dusen, Maurice Verne

2012-06-07T23:59:59.000Z

427

Argonne CNM Highlight: Reverse Chemical Switching of a Ferroelectric Film  

NLE Websites -- All DOE Office Websites (Extended Search)

Reverse Chemical Switching of a Ferroelectric Film Reverse Chemical Switching of a Ferroelectric Film Reverse Chemmical Switching of a Ferroelectric Film Ferroelectric materials display a spontaneous electric polarization below the Curie temperature that can be reoriented, typically by applying an electric field. In this study, researchers from Argonne, Northern Illinois University, and The University of Pennsylvania have demonstrated that the chemical environment can control the polarization orientation in an ultrathin ferroelectric film. This is complementary to recent predictions that polarization can affect surface chemistry and illuminates potential applications in sublithographic patterning and electrically tunable catalysts. In situ synchrotron X-ray scattering measurements showed that high or low

428

Biphase turbine for reverse osmosis desalination. Final report  

SciTech Connect

A new hydraulic reaction turbine was designed to recover the power available in the high-pressure waste-brine stream of reverse osmosis desalination systems. A reaction turbine sized for reverse-osmosis systems producing 600 gph was built and tested. The turbine performed well driving either a variable-speed pump or an electrical generator. Measured turbine efficiency (shaft power divided by available power) was 63%, compared with a prediction of 67%. The turbine can be built with larger capacity to reduce the size, weight and power consumption of reverse osmosis desalination systems. Efficiency of larger units is predicted to lie in the range of 65 to 70%.

Limburg, P.L.

1982-12-01T23:59:59.000Z

429

Purication of reghting water containing a uorinated surfactant by reverse osmosis coupled to  

E-Print Network (OSTI)

Purication of reghting water containing a uorinated surfactant by reverse osmosis coupled. Reverse osmosis of pretreated pilot reghting water and concentrated model solutions of pretreated reghting. The concentrate from reverse osmosis could be recycled in electrocoagulation-ltration. Experimental results

Paris-Sud XI, Université de

430

Fouling of reverse osmosis membranes by hydrocarbonated and fluorinated surfactants contained in firefighting water  

E-Print Network (OSTI)

Title: Fouling of reverse osmosis membranes by hydrocarbonated and fluorinated surfactants osmosis efficiently treated the water from fire extinguishment. In this work we focused on the reverse surfactants [1]. Experimental results indicated that electrocoagulation and filtration followed by reverse

Paris-Sud XI, Université de

431

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)

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

Biggs, Alan R.

432

Removal of radionuclides in drinking water by membrane treatment using ultrafiltration, reverse osmosis and electrodialysis reversal  

Science Journals Connector (OSTI)

A pilot plant had been built to test the behaviour of ultrafiltration (UF), reverse osmosis (RO), and electrodialysis reversal (EDR) in order to improve the quality of the water supplied to Barcelona metropolitan area from the Llobregat River. This paper presents results from two studies to reduce natural radioactivity. The results from the pilot plant with four different scenarios were used to design the full-scale treatment plant built (SJD WTP). The samples taken at different steps of the treatment were analysed to determine gross alpha, gross beta and uranium activity. The results obtained revealed a significant improvement in the radiological water quality provided by both membrane techniques (RO and EDR showed removal rates higher than 60%). However, UF did not show any significant removal capacity for gross alpha, gross beta or uranium activities. RO was better at reducing the radiological parameters studied and this treatment was selected and applied at the full scale treatment plant. The RO treatment used at the SJD WTP reduced the concentration of both gross alpha and gross beta activities and also produced water of high quality with an average removal of 95% for gross alpha activity and almost 93% for gross beta activity at the treatment plant.

M. Montaña; A. Camacho; I. Serrano; R. Devesa; L. Matia; I. Vallés

2013-01-01T23:59:59.000Z

433

Effects of atmospheric conditions and control surface deflections on vortex characteristics  

E-Print Network (OSTI)

I I I i. C iS OF:"-:, ','". : iFII! 2! C CO", Df if Of!S f'-, 'ID CO, ", IROI ':L'll ', CI DI. I I ECT IOIIS O', I 'ilORT:-X ' I~OR;. C I L!If ISTICS 0 Thesis by CALVfl'I L!O'. , 'PRD SIIEIIKIR, JR. Subr~i fis!i to the G! ', 'uete Col ieije...7, SST Ci'rcorde, C-SA, and others, induce 'tr. ailing r, ing iiI! vor'-ic, s ?aiich pr: sent a hazard Lo stnal1er ait craft. In this Itir!Osti(dation such vr. i tex charac'ieristics as I!ave Fornations, r;0!e Ienrgths, b(eak t&1es, and vortex...

Shenkir, Calvin Edward

2012-06-07T23:59:59.000Z

434

Mechanical (acoustic?like) wave propagation along a vortex array in the superconducting heterostructure  

Science Journals Connector (OSTI)

Magnetic flux can penetrate the type ? II superconductor in the form of Abrikosov vortices (also called flux lines flux tubes or fluxons) each carrying a quantum of magnetic flux. These tiny vortices of supercurrent tend to arrange themselves in a triangular or quadratic flux?line lattice. Since the vortices are formed by the applied magnetic field around of each of them the supercurrent flows. Moreover there also exist some Lorentz force interactions among them. Those interactions form an origin of an additional mechanical (stress) field occurring in the type?II superconductor. The paper deals with an analysis of elastic (acoustic?like) wave propagation solely along vortices in a heterostructure consisted of the superconducting layer put on the superconducting substrate. Dispersion and the amplitude distribution of those waves in the vortex field existing in that structure has been presented.

Bogdan T. Maruszewski; Andrzej Drzewiecki; Roman Starosta

2008-01-01T23:59:59.000Z

435

Plasma resonance at low magnetic fields as a probe of vortex line meandering in layered superconductors  

Science Journals Connector (OSTI)

We consider the magnetic-field dependence of the plasma resonance frequency in pristine and in irradiated Bi2Sr2CaCu2O8 crystals near Tc. At low magnetic fields we relate linear in field corrections to the plasma frequency to the average distance between the pancake vortices in the neighboring layers (wandering length). We calculate the wandering length in the case of thermal wiggling of vortex lines, taking into account both Josephson and magnetic interlayer coupling of pancakes. Analyzing experimental data, we found that (i) the wandering length becomes comparable with the London penetration depth near Tc and (ii) at small melting fields (line liquid phase in this field range. We also found that pinning by columnar defects affects weakly the field dependence of the plasma resonance frequency near Tc.

L. N. Bulaevskii; A. E. Koshelev; V. M. Vinokur; M. P. Maley

2000-02-01T23:59:59.000Z

436

Plasma resonance at low magnetic fields as a probe of vortex line meandering in layered superconductors  

E-Print Network (OSTI)

We consider the magnetic field dependence of the plasma resonance frequency in pristine and in irradiated Bi$_2$Sr$_2$CaCu$_2$O$_8$ crystals near $T_c$. At low magnetic fields we relate linear in field corrections to the plasma frequency to the average distance between the pancake vortices in the neighboring layers (wandering length). We calculate the wandering length in the case of thermal wiggling of vortex lines, taking into account both Josephson and magnetic interlayer coupling of pancakes. Analyzing experimental data, we found that (i) the wandering length becomes comparable with the London penetration depth near T$_{c}$ and (ii) at small melting fields ($line liquid phase in this field range. We also found that pinning by columnar defects affects weakly the field dependence of the plasma resonance frequency near $T_c$.

L. N. Bulaevskii; A. E. Koshelev; V. M. Vinokur; M. P. Maley

1999-07-29T23:59:59.000Z

437

Vortex precession frequency and its amplitude-dependent shift in cylindrical nanomagnets  

SciTech Connect

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.

Metlov, Konstantin L., E-mail: metlov@fti.dn.ua [Donetsk Institute for Physics and Technology NAS, Donetsk 83114 (Ukraine)

2013-12-14T23:59:59.000Z

438

Cyclostrophic adjustment in swirling gas flows and the Ranque-Hilsch vortex tube effect  

SciTech Connect

A theoretical analysis of cyclostrophic adjustment is presented; i.e., adjustment to balance between pressure gradient and centrifugal force in axisymmetric flow of an inviscid gas is examined. The solution to the problem is represented as the sum of a time-independent (balanced) and time-dependent (wave) components. It is shown that the wave component of the flow in an unbounded domain decays with time, and the corresponding solution reduces to the balanced component. In a bounded domain, the balanced flow component exists against the background of undamped acoustic waves. It is found that the balanced flow is thermally stratified at Mach numbers close to unity, with a substantial decrease in gas temperature (to between -50 and -100 deg. C) in the axial region. This finding, combined with the results of special experiments, is used to explain the Ranque-Hilsch vortex tube effect.

Kalashnik, M. V., E-mail: lingel@obninsk.com; Visheratin, K. N. [SPA Typhoon (Russian Federation)], E-mail: kvisher@typhoon.obninsk.ru

2008-04-15T23:59:59.000Z

439

Dynamic Inductance in Saturated Cores Fault Current Limiters  

Science Journals Connector (OSTI)

The saturated cores Fault Current Limiter (FCL) is one of the leading ... for providing a commercial robust solution to the fault current problem. Basically, the saturated cores FCL ... its saturated cores state ...

Y. Nikulshin; Y. Wolfus; A. Friedman…

2014-09-01T23:59:59.000Z

440

TCEQ-CoreDataForm | Open Energy Information  

Open Energy Info (EERE)

TCEQ-CoreDataForm Jump to: navigation, search OpenEI Reference LibraryAdd to library Form: TCEQ-CoreDataForm Abstract This is the core data form from the Texas Commission on...

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Unearthing the Composition of Our Planet's Core  

NLE Websites -- All DOE Office Websites (Extended Search)

Unearthing the Composition of Our Planet's Core Unearthing the Composition of Our Planet's Core The chemical composition of the Earth's core is surprisingly complicated, according to high-temperature, high-pressure experiments conducted by University of Chicago scientists using the William M. Keck High Pressure Laboratory at the GSECARS facility, APS sector 13. This research has produced experimental evidence suggesting that the Earth's inner core largely consists of two exotic forms of iron (rather than one as previously thought) that appear to be alloyed with silicon. Backscattered electron image of the quenched laser-heated diamond anvil cell sample from 31 GPa and 1976K. ( J.-F. Lin et al.) Above: Backscattered electron image of the quenched laser-heated diamond anvil cell sample from 31 GPa and 1976K. ( J.-F. Lin et al.)

442

GreenCore Capital | Open Energy Information  

Open Energy Info (EERE)

GreenCore Capital GreenCore Capital Jump to: navigation, search Logo: GreenCore Capital Name GreenCore Capital Address 10509 Vista Sorrento Parkway Place San Diego, California Zip 92121 Region Southern CA Area Product Invests in developing promising renewable energy companies Website http://www.greencorecapital.co Coordinates 32.898095°, -117.215736° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":32.898095,"lon":-117.215736,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

443

A New Greenland Deep Ice Core  

Science Journals Connector (OSTI)

...isotopic profile with that from camp Century and with a deep-sea foraminifera...deep-sea cores. The redated Camp Century record suggests a dramatic termination...CENTURIES OF CLIMATIC RECORD FROM CAMP CENTURY ON GREENLAND ICE SHEET, SCIENCE...

W. Dansgaard; H. B. Clausen; N. Gundestrup; C. U. Hammer; S. F. Johnsen; P. M. Kristinsdottir; N. Reeh

1982-12-24T23:59:59.000Z

444

ICE CORE RECORDS | Greenland Stable Isotopes  

Science Journals Connector (OSTI)

Abstract Greenland ice cores contain a wealth of information on past climatic conditions throughout the Northern Hemisphere. A historical perspective on the climatic interpretation of stable isotopes in water and ice is presented in the introduction, while the remainder of the article is devoted to the current interpretation of stable isotope data from Greenland ice cores. The progress in our understanding of stable isotope signals, on timescales from seasons to glacial cycles, is discussed and evaluated through numerous examples from Greenland ice cores. Stable isotope profiles from the Camp Century, Dye-3, GISP2, GRIP, NGRIP, and Renland deep ice cores are emphasized, as they all provide climatic information dating back into the Eemian period.

B.M. Vinther; S.J. Johnsen

2013-01-01T23:59:59.000Z

445

Bacterial Fouling in a Model Core System  

Science Journals Connector (OSTI)

...to reduce permeability. Therefore...aspects of reservoir rock, without...an "open" sandstone. Thus, especially...changes in permeability that occurred...22). The porosity of the cores...liquid storage reservoir with a capacity...

J. C. Shaw; B. Bramhill; N. C. Wardlaw; J. W. Costerton

1985-03-01T23:59:59.000Z

446

Crystallization of the crenarchaeal SRP core  

Science Journals Connector (OSTI)

The conserved ribonucleoprotein core of the signal recognition particle (SRP) has been crystallized. Both crystal forms are highly twinned and an explanation for the possible tetartohedral twinning is presented.

Rosendal, K.R.

2003-12-18T23:59:59.000Z

447

Xenon Oscillations in a VVÉR-1000 Core  

Science Journals Connector (OSTI)

Xenon oscillations – periodic redistribution of the power over ... the large size of this core. The xenon oscillations can be conventionally divided into axial, radial ... paper, methods are described for initiat...

V. A. Tereshonok; V. S. Stepanov; V. P. Povarov; O. V. Lebedev…

2002-10-01T23:59:59.000Z

448

Environmental impact of various kayak core materials  

E-Print Network (OSTI)

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 ...

Kirkland, David R. (David Roger)

2008-01-01T23:59:59.000Z

449

PRELIMINARY TIME ESTIMATES FOR CORING OPERATIONS  

E-Print Network (OSTI)

EQUATIONS 17 FIGURE 1. DRILL STRING ROUND TRIP 19 FIGURE 2. STANDARD ROTARY CORING (RCB) WIRELINE TRIP 21) WIRELINE TRIP 25 FIGURE 5. ESTIMATED RIGGING, WIRELINE, AND SCANNING TIME FOR REENTRY. 27 #12;Preliminary

450

MagLab - Magnetic Core Memory Tutorial  

NLE Websites -- All DOE Office Websites (Extended Search)

grid is made up of wires. The purpose of the horizontal and vertical X and Y Address Lines is to direct current to a specific core. The purpose of the diagonal Sense Lines is to...

451

Armor systems including coated core materials  

DOE Patents (OSTI)

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.

2013-10-08T23:59:59.000Z

452

Armor systems including coated core materials  

DOE Patents (OSTI)

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.

Chu, Henry S. (Idaho Falls, ID); Lillo, Thomas M. (Idaho Falls, ID); McHugh, Kevin M. (Idaho Falls, ID)

2012-07-31T23:59:59.000Z

453

Panelized wall system with foam core insulation  

DOE Patents (OSTI)

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

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

2009-10-20T23:59:59.000Z

454

Iowa's first electrodialysis reversal water treatment plant  

Science Journals Connector (OSTI)

In 1979 the City of Washington was notified by the Iowa Department of Natural Resources (IDNR) that the City was in violation of the radium standard for drinking water. The City of Washington authorized an engineering study to determine the most cost-effective and practical way to remove radium and, at the same time, improve overall water quality. Several possible treatment alternatives were evaluated. It was finally decided to utilize electrodialysis reversal (EDR). Washington obtains its water from three deep wells ranging in capacity from 600–780 gpm. The untreated water withdrawn from the wells first passes through the EDR units. There are three EDR units, each able to produce 285 gpm of finished water. In the future, another EDR unit can be easily added to the other three units, since the new plant was built and plumbed for an additional EDR unit if water demand increased. The Jordan aquifer supply is adequate for current and future needs. The average daily water usage in 1993 was 818,000 gal/d. In order to meet peak flows, it is possible to bypass the EDR units with part of the untreated water and then blend treated and untreated water. The treated water meets IDNR standards of 5.0 pC/L. After the EDR units, the water flows through an aerator where odor-causing gases and carbon dioxide are removed. Aeration reduces the amount of caustic soda and chlorine used in the finished water. The hydrogen sulfide gas leaves the water as it passes through the aerator, and this loss of gas creates less chlorine demand. Total and free chlorine residuals are now detected in every water main of the town, whereas before, the residuals would not be detected in certain area of Washington. Phosphates have been cut back from 7 pounds per day to one pound per day. Better water quality is now being achieved with fewer chemicals added to the finished water. Washington's water treatment plant is the first municipal EDR plant in the State of Iowa and one of the largest municipal installations in the United States.

John Hays

2000-01-01T23:59:59.000Z

455

Reversible Poisoning of the Nickel/Zirconia Solid Oxide Fuel...  

NLE Websites -- All DOE Office Websites (Extended Search)

Poisoning of the NickelZirconia Solid Oxide Fuel Cell Anodes by Hydrogen Chloride in Coal Gas. Reversible Poisoning of the NickelZirconia Solid Oxide Fuel Cell Anodes by Hydrogen...

456

Reverse logistics network design for spent batteries: a simulation study  

Science Journals Connector (OSTI)

End of life (EOL) product management, which encompasses reuse, remanufacturing and materials recycling, requires a structured reverse logistic network in order to collect products efficiently at the end of their life cycle. This work describes modelling and simulation of reverse logistics network design for collection of spent batteries for Sangrur District of North India. To compare different order assignment, a simulation model of forward and reverse logistics networks has been developed. Several simulation experiments have been designed to analyse impact of the system design factors on the operational performance of the reverse logistics system. The simulation results show that the model presented in this paper calculates the battery collection cost, transfer time, transfer cost, and resource utilisation in a predictable manner. Moreover, it provides a tool to understand how the system behaves by carrying out 'what-if' assessments and to identify which parameters are most important for more detailed analysis.

Arvind Jayant; Pardeep Gupta; S.K. Garg

2014-01-01T23:59:59.000Z

457

Reverse Auction Bidding- A Study of Industry Professionals  

E-Print Network (OSTI)

study. (Professional Paper), TAMU, College Station. Smeltzer, L. R., & Carr, A. S. (2003). Electronic reverse auctions: Promises, risks and conditions for success. Industrial Marketing Management, 32(6), 481-488 Thompson, J., & Knoll, H...

Piper, Robert

2013-12-06T23:59:59.000Z

458

First-Principles Prediction of Thermodynamically Reversible Hydrogen...  

NLE Websites -- All DOE Office Websites (Extended Search)

First-Principles Prediction of Thermodynamically Reversible Hydrogen Storage Reactions in the Li-Mg-Ca-B-H system Home Author: V. Ozolins, E. H. Majzoub, C. Wolverton Year: 2009...

459

Hydrogen production in a reversible flow filtration combustion reactor  

Science Journals Connector (OSTI)

The noncatalytic process of syngas production by means of partial oxidation of ... by air oxygen in a reversible flow filtration combustion reactor has been investigated experimentally. We have ... providing the ...

Yu. M. Dmitrenko; P. A. Klevan

2011-11-01T23:59:59.000Z

460

Global confinement and discrete dynamo activity in the MST reversed...  

NLE Websites -- All DOE Office Websites (Extended Search)

confinement and discrete dynamo activity in the MST reversed-field pinch* S. Hokin,+ A. Almagri, S. Assadi, J. Beckstead, G. Chartas, N. Cracker, M. Cudzinovic, D. Den Hat-tog, FL...

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

NETL: Control Technology: ElectroCore Separator  

NLE Websites -- All DOE Office Websites (Extended Search)

ElectroCore Separator ElectroCore Separator LSR Technologies and its subcontractors designed and installed a 8,500 m3/hr (5,000 acfm) Advanced ElectroCore system and a dry sulfur scrubber to test it using an exhaust gas slipstream at Alabama Power Company's Gaston Steam Plant. Shakedown is scheduled for August 15, 2001. The exhaust gas will be from Unit #4 of a 270 MWe sub-critical, pulverized coal boiler burning a low-sulfur bituminous coal. The Advanced ElectroCore system will consist of a conventional upstream ESP, a dry SO2 scrubber, a particle precharger and an Advanced ElectroCore separator. Particle concentrations and size distributions will be measured at the ESP inlet, at the dry scrubber outlet and at the ElectroCore outlet. The concentration of 12 common HAPs will be measured at these locations as well. For purposes of project organization and monitoring, the work will be divided into nine (9) tasks described below.

462

Formed Core Sampler Hydraulic Conductivity Testing  

SciTech Connect

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

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

2012-09-25T23:59:59.000Z

463

Solid oxide fuel cell having monolithic core  

DOE Patents (OSTI)

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

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

1983-10-12T23:59:59.000Z

464

Early Type Galaxy Core Phase Densities  

E-Print Network (OSTI)

Early type galaxies, ellipticals and S0's, have two distinct core density profiles, either a power law or nearly flat in projection. The two core types are distributed with substantial overlap in luminosity, radius, mass and velocity dispersion, however, the cores separate into two distinct distributions in their coarse grain phase density, Q_0 = rho/sigma^3,suggesting that dynamical processes played a dominant role in their origin. The transition phase density separating the two elliptical types is approximately 0.003 M_sun pc^-3 km^-3 s^3,. The Q_0*M_c^2 vs M_c diagram shows that globular clusters, nuclear star clusters and power-law cores fall on what is likely a "collisional" sequence of inspiralling globular clusters. on which the relative core mass excess varies as the bulk stellar mass to the -0.34+/-0.08 power, close to predictions, albeit with a correlation coefficient of -0.46. Both power-law and cored galaxies lie on a single sequence of approximately Q_0 ~r_c^-2.2, suggesting that transport proces...

Carlbeg, Raymond

2014-01-01T23:59:59.000Z

465

Synthesis of Reversible Functions Using Various Gate Libraries and Design Specifications.  

E-Print Network (OSTI)

?? This dissertation is devoted to efficient automated logic synthesis of reversible circuits using various gate types and initial specifications. These Reversible circuits are of… (more)

Alhagi, Nouraddin

2010-01-01T23:59:59.000Z

466

Journal Article: Real-time sub-Ångstrom imaging of reversible...  

Office of Scientific and Technical Information (OSTI)

imaging of reversible and irreversible conformations in rhodium catalysts and graphene Citation Details Title: Real-time sub-ngstrom imaging of reversible and...

467

E-Print Network 3.0 - analogue reverse transcriptase Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

0 Summary: of the Human Immunodeficiency Virus Type 1 Reverse Transcriptase by d4TTP: an Equivalent Incorporation... (HIV-1) reverse transcriptase (RT), there is little detailed...

468

Nano-scale Composite Hetero-structures: Novel High Capacity Reversible...  

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

Nano-scale Composite Hetero-structures: Novel High Capacity Reversible Anodes for Lithium-ion Batteries Nano-scale Composite Hetero-structures: Novel High Capacity Reversible...

469

Reverse osmosis treatment to remove inorganic contaminants from drinking water  

SciTech Connect

The purpose of the research project was to determine the removal of inorganic contaminants from drinking water using several state-of-the-art reverse osmosis membrane elements. A small 5-KGPD reverse osmosis system was utilized and five different membrane elements were studied individually with the specific inorganic contaminants added to several natural Florida ground waters. Removal data were also collected on naturally occurring substances.

Huxstep, M.R.; Sorg, T.J.

1987-12-01T23:59:59.000Z

470

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

NLE Websites -- All DOE Office Websites (Extended Search)

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

471

Core Analysis At International Geothermal Area, Indonesia (Boitnott...  

Open Energy Info (EERE)

Area Indonesia Exploration Technique Core Analysis Activity Date Usefulness not indicated DOE-funding Unknown References Greg N. Boitnott (2003) Core Analysis For The Development...

472

Core Analysis At Fenton Hill HDR Geothermal Area (Laughlin, Et...  

Open Energy Info (EERE)

Activity Details Location Fenton Hill HDR Geothermal Area Exploration Technique Core Analysis Activity Date - 1983 Usefulness useful DOE-funding Unknown Notes A few cores...

473

DOE CYBER SECURITY EBK: MINIMUM CORE COMPETENCY TRAINING REQUIREMENTS...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

DOE CYBER SECURITY EBK: MINIMUM CORE COMPETENCY TRAINING REQUIREMENTS DOE CYBER SECURITY EBK: CORE COMPETENCY TRAINING REQUIREMENTS: CA Cybersecurity Program Manager (CSPM...

474

Smart” Diblock Copolymers as Templates for Magnetic-Core...  

NLE Websites -- All DOE Office Websites (Extended Search)

Smart” Diblock Copolymers as Templates for Magnetic-Core Gold-Shell Nanoparticle Synthesis. Smart” Diblock Copolymers as Templates for Magnetic-Core Gold-Shell...

475

OpenStudio Core Development and Deployment Support - 2014 BTO...  

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

Core Development and Deployment Support - 2014 BTO Peer Review OpenStudio Core Development and Deployment Support - 2014 BTO Peer Review Presenter: Larry Brackney, National...

476

E-Print Network 3.0 - air-suspended solid-core fibers Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

solid core subwavelength ber (a) and suspended porous core... December 2011 | 41 TERAHERTZ Suspended Core Subwavelength Plastic ... Source: Skorobogatiy, Maksim -...

477

Large-Eddy Simulation of Stratified Turbulence. Part II: Application of the Stretched-Vortex Model to the Atmospheric Boundary Layer  

Science Journals Connector (OSTI)

The buoyancy-adjusted stretched-vortex subgrid-scale (SGS) model is assessed for a number of large-eddy simulations (LESs) corresponding to diverse atmospheric boundary layer conditions. The cases considered are free convection, a moderately ...

Georgios Matheou; Daniel Chung

2014-12-01T23:59:59.000Z

478

205Tl NMR observation of vortex lattice formation in the high temperature superconductor Tl2Ba2CuO6  

Science Journals Connector (OSTI)

We report on the asymmetric field distribution of the triangular vortex lattice in the superconductor Tl2Ba2CuO6 as observed by205Tl NMR atB a =4.26 T. A penetra...

M. Mehring; F. Hentsch; Hj. Mattausch…

1989-01-01T23:59:59.000Z

479

Satellite Data Assimilation in Numerical Weather Prediction Models. Part II: Uses of Rain-Affected Radiances from Microwave Observations for Hurricane Vortex Analysis  

Science Journals Connector (OSTI)

A hybrid variational scheme (HVAR) is developed to produce the vortex analysis associated with tropical storms. This scheme allows for direct assimilation of rain-affected radiances from satellite microwave instruments. In the HVAR, the ...

Fuzhong Weng; Tong Zhu; Banghua Yan

2007-11-01T23:59:59.000Z

480

The benefits of hybridising electrodialysis with reverse osmosis  

Science Journals Connector (OSTI)

Abstract A cost analysis reveals that hybridisation of electrodialysis with reverse osmosis is only justified if the cost of water from the reverse osmosis unit is less than 40% of that from a stand-alone electrodialysis system. In such cases the additional reverse osmosis costs justify the electrodialysis cost savings brought about by shifting salt removal to higher salinity, where current densities are higher and equipment costs lower. Furthermore, the analysis suggests that a simple hybrid configuration is more cost effective than a recirculated hybrid, a simple hybrid being one where the reverse osmosis concentrate is fed to the electrodialysis stack and the products from both units are blended, and a recirculated being one hybrid involving recirculation of the electrodialysis product back to the reverse osmosis unit. The underlying rationale is that simple hybridisation shifts salt removal away from the lowest salinity zone of operation, where salt removal is most expensive. Further shifts in the salinity at which salt is removed, brought about by recirculation, do not justify the associated increased costs of reverse osmosis.

Ronan K. McGovern; Syed M. Zubair; John H. Lienhard V

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex core reversal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

A survey of ideal fluid propeller theories and a study of the effects of aerodynamic propeller loading on trailing vortex induced velocity and thrust  

E-Print Network (OSTI)

A SURVEY OF IDEAL FLUID PRO~ THEORIES AND A STUIE OP THE EFFECTS OF AERODYNAMIC PRO~ LOADING ON TRAILING VORTEX INDUCED VELOCITY AND THRUST A Thesis EDWARD MADISON ~ Suhmitted to the Graduate College of Texas A&M University in Partial... fulfillment of the requirement for the degree of MASTER OF SCIENCE August 1969 h'h, jor Suhgect: Mechanical Engineering A SURVEY OF IDEAL FLUID PROPELLEB THEORIES AND A STUDY OF THE EFFKTS OF AERODYKVGC PROPELLER LOADING ON TRAILING VORTEX INDUCED...

Kelley, Edward Madison

2012-06-07T23:59:59.000Z

482

A model of the lateral line of fish for vortex sensing This article has been downloaded from IOPscience. Please scroll down to see the full text article.  

E-Print Network (OSTI)

A model of the lateral line of fish for vortex sensing This article has been downloaded from.1088/1748-3182/7/3/036016 A model of the lateral line of fish for vortex sensing Zheng Ren1 and Kamran Mohseni1,2,3,4 1 Department.iop.org/BB/7/036016 Abstract In this paper, the lateral line trunk canal (LLTC) of a fish is modeled

Mohseni, Kamran

483

Calorimetric study of the transitions between the different vortex states in YBa{sub 2}Cu{sub 3}O{sub 7}.  

SciTech Connect

We have studied the vortex phase diagram of YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} (YBCO) in very strong magnetic field (0-26 Tesla) by a.c. calorimetry. We describe the anomalies associated with the transitions between the different vortex states (solid, liquid, and glass), with special emphasis on the first order flux lattice melting.

Bouquet, F.; Calemczuk, R.; Crabtree, G. W.; Erb, A.; Fisher, R. A.; Junod, A.; Kwok, W. K.; Marcenat, C.; Phillips, N. E.; Roulin, M.; Schilling, A.; Welp, U.

1999-08-17T23:59:59.000Z

484

Overview on Hydrate Coring, Handling and Analysis  

SciTech Connect

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

Jon Burger; Deepak Gupta; Patrick Jacobs; John Shillinglaw

2003-06-30T23:59:59.000Z

485

CFD Analysis of Core Bypass Phenomena  

SciTech Connect

The U.S. Department of Energy is exploring the potential for the VHTR which will be either of a prismatic or a pebble-bed type. One important design consideration for the reactor core of a prismatic VHTR is coolant bypass flow which occurs in the interstitial regions between fuel blocks. Such gaps are an inherent presence in the reactor core because of tolerances in manufacturing the blocks and the inexact nature of their installation. Furthermore, the geometry of the graphite blocks changes over the lifetime of the reactor because of thermal expansion and irradiation damage. The existence of the gaps induces a flow bias in the fuel blocks and results in unexpected increase of maximum fuel temperature. Traditionally, simplified methods such as flow network calculations employing experimental correlations are used to estimate flow and temperature distributions in the core design. However, the distribution of temperature in the fuel pins and graphite blocks as well as coolant outlet temperatures are strongly coupled with the local heat generation rate within fuel blocks which is not uniformly distributed in the core. Hence, it is crucial to establish mechanistic based methods which can be applied to the reactor core thermal hydraulic design and safety analysis. Computational Fluid Dynamics (CFD) codes, which have a capability of local physics based simulation, are widely used in various industrial fields. This study investigates core bypass flow phenomena with the assistance of commercial CFD codes and establishes a baseline for evaluation methods. A one-twelfth sector of the hexagonal block surface is modeled and extruded down to whole core length of 10.704m. The computational domain is divided vertically with an upper reflector, a fuel section and a lower reflector. Each side of the sector grid can be set as a symmetry boundary

Richard W. Johnson; Hiroyuki Sato; Richard R. Schultz

2010-03-01T23:59:59.000Z

486

CFD Analysis of Core Bypass Phenomena  

SciTech Connect

The U.S. Department of Energy is exploring the potential for the VHTR which will be either of a prismatic or a pebble-bed type. One important design consideration for the reactor core of a prismatic VHTR is coolant bypass flow which occurs in the interstitial regions between fuel blocks. Such gaps are an inherent presence in the reactor core because of tolerances in manufacturing the blocks and the inexact nature of their installation. Furthermore, the geometry of the graphite blocks changes over the lifetime of the reactor because of thermal expansion and irradiation damage. The existence of the gaps induces a flow bias in the fuel blocks and results in unexpected increase of maximum fuel temperature. Traditionally, simplified methods such as flow network calculations employing experimental correlations are used to estimate flow and temperature distributions in the core design. However, the distribution of temperature in the fuel pins and graphite blocks as well as coolant outlet temperatures are strongly coupled with the local heat generation rate within fuel blocks which is not uniformly distributed in the core. Hence, it is crucial to establish mechanistic based methods which can be applied to the reactor core thermal hydraulic design and safety analysis. Computational Fluid Dynamics (CFD) codes, which have a capability of local physics based simulation, are widely used in various industrial fields. This study investigates core bypass flow phenomena with the assistance of commercial CFD codes and establishes a baseline for evaluation methods. A one-twelfth sector of the hexagonal block surface is modeled and extruded down to whole core length of 10.704m. The computational domain is divided vertically with an upper reflector, a fuel section and a lower reflector. Each side of the one-twelfth grid can be set as a symmetry boundary

Richard W. Johnson; Hiroyuki Sato; Richard R. Schultz

2009-11-01T23:59:59.000Z

487

Optimization of membrane stack configuration for efficient hydrogen production in microbial reverse-electrodialysis electrolysis cells coupled  

E-Print Network (OSTI)

Optimization of membrane stack configuration for efficient hydrogen production in microbial reverse-electrodialysis 2013 Keywords: Microbial reverse-electrodialysis electrolysis cell Ammonium bicarbonate Hydrogen reverse electrodialysis (RED) stack into the MEC, which was called a microbial reverse-electrodialysis

488

Experimental and thermodynamical analyses of the diesel exhaust vortex generator heat exchanger for optimizing its operating condition  

Science Journals Connector (OSTI)

Abstract In this research, a vortex generator heat exchanger is used to recover exergy from the exhaust of an OM314 diesel engine. Twenty vortex generators with 30° angle of attack are used to increase the heat recovery as well as the low back pressure in the exhaust. The experiments are prepared for five engine loads (0, 20, 40, 60 and 80% of full load), two exhaust gases amount (50 and 100%) and four water mass flow rates (50, 40, 30 and 20 g/s). After a thermodynamical analysis on the obtained data, an optimization study based on Central Composite Design (CCD) is performed due to complex effect of engine loads and water mass flow rates on exergy recovery and irreversibility to reach the best operating condition.

M. Hatami; D.D. Ganji; M. Gorji-Bandpy

2015-01-01T23:59:59.000Z

489

Interstitials, Vacancies and Dislocations in Flux-Line Lattices: A Theory of Vortex Crystals, Supersolids and Liquids  

E-Print Network (OSTI)

We study a three dimensional Abrikosov vortex lattice in the presence of an equilibrium concentration of vacancy, interstitial and dislocation loops. Vacancies and interstitials renormalize the long-wavelength bulk and tilt elastic moduli. Dislocation loops lead to the vanishing of the long-wavelength shear modulus. The coupling to vacancies and interstitials - which are always present in the liquid state - allows dislocations to relax stresses by climbing out of their glide plane. Surprisingly, this mechanism does not yield any further independent renormalization of the tilt and compressional moduli at long wavelengths. The long wavelength properties of the resulting state are formally identical to that of the ``flux-line hexatic'' that is a candidate ``normal'' hexatically ordered vortex liquid state.

M. Cristina Marchetti; Leo Radzihovsky

1999-07-01T23:59:59.000Z

490

Vortex graphs as N-omers and CP(N-1) Skyrmions in N-component Bose-Einstein condensates  

E-Print Network (OSTI)

Stable vortex N-omers are constructed in coherently coupled N-component Bose-Einstein condensates. We classify all possible N-omers in terms of the mathematical graph theory and numerically construct all graphs for N=2,3,4. We also find that N-omers are well described as CP(N-1) skyrmions when inter-component and intra-component couplings are U(N) symmetric, and we evaluate their size dependence on the Rabi coupling.

Minoru Eto; Muneto Nitta

2013-03-25T23:59:59.000Z

491

CA Core Competency Worksheet August 2010  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

CA Core Competency Worksheet August 2010 CA Core Competency Worksheet August 2010 1 DOE CYBER SECURITY EBK: CORE COMPETENCY TRAINING REQUIREMENTS Key Cyber Security Role: Certification Agent (CA) (Also referred to as Security Control Assessor) Role Definition: The CA is the individual responsible for assessing the management, operational, assurance, and technical security controls implemented on an information system via security testing and evaluation (ST&E) methods. This individual must be independent of system development, operation, and deficiency mitigation. Competency Area: Data Security Functional Requirement: Design Competency Definition: Refers to the application of the principles, policies, and procedures necessary to ensure the confidentiality, integrity, availability, and privacy of data in all forms of media (i.e., electronic

492

Deterministic Ratchets, Circle Maps, and Current Reversals R. Salgado-Garcia,1,2  

E-Print Network (OSTI)

- rameters such as ``current quantization,'' current reversal, and devil's staircase phenomena [6,7]. Though

Aldana, Maximino

493

Analytical Chemistry Core Capability Assessment - Preliminary Report  

SciTech Connect

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

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

2012-05-16T23:59:59.000Z

494

Characterization of aircraft noise during thrust reverser engagement  

Science Journals Connector (OSTI)

Airport noise impact on communities has been an area of considerable study. However it has been determined that thrust reverser engagement is an area requiring further research. This paper presents findings on thrust reverser from a noise study done at Washington?Dulles International Airport (IAD) in October of 2004. Previous studies have found that high levels of acoustic energy in commercial aircraft during takeoff are contained below 300 Hz [Sharp Ben H. Guovich Yuri A. and Albee William W. ‘‘Status of Low?Frequency Aircraft Noise Research and Mitigation ’’ Wyle Report WR 01?21 San Francisco September 2001]. Preliminary analysis of thrust reverser signatures indicates similar findings. A categorization of aircraft noise during thrust reverser engagement is given and looks at factors that may affect the noise characteristics. Some of these factors include: plane type engine type and thrust ratings. In addition a brief analysis of frequency weightings of the Equivalent Sound Level (Leq) and Sound Exposure Level (SEL) metrics and their application to thrust reverser noise is discussed. [Work supported by the Federal Aviation Administration.

2005-01-01T23:59:59.000Z

495

Characterization of the fouling phenomenon in reverse osmosis  

SciTech Connect

This dissertation explores the application of a bench scale reverse osmosis test cell apparatus as a research tool. This versatile system was used to explore the response of a reverse osmosis membrane to various types of feedwaters. As a result of this research, an easy, accurate experimental method for predicting the rejection in any reverse osmosis system has been developed and demonstrated. The dissertation illustrates a simple procedure to identify if a precipitating feedwater solution will foul a reverse osmosis membrane. The research also presents evidence that suggests that the common practice of increasing feed flow rates to clean a membrane may not always be an acceptable method to revive a system. In addition to this information about the RO systems, the dissertation provides insight into the environment around the membrane surface. Statistically significant information about the nature and behavior of the membrane permeation coefficient is presented. Evidence is provided to demonstrate the negative effects on membrane performance of small amounts of grease contamination from the process equipment. Insight into the resistive nature of membranes, boundary layers, and fouling deposits is also presented. Throughout the course of this research, the relationship between concentration polarization and the permeate flux is illustrated. This is done first in the traditional terms of wall concentration, and later in terms of flow resistance. This dissertation also provides an experimental demonstration of both the detachment of a boundary layer from a membrane and the resistive nature of a precipitated fouling layer in a reverse osmosis system.

Barger, M.

1989-01-01T23:59:59.000Z

496

Reactor Core Assembly - HFIR Technical Parameters | ORNL Neutron Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

Home › Facilities › HFIR › Reactor Core Assembly Home › Facilities › HFIR › Reactor Core Assembly Reactor Core Assembly The reactor core assembly is contained in an 8-ft (2.44-m)-diameter pressure vessel located in a pool of water. The top of the pressure vessel is 17 ft (5.18 m) below the pool surface, and the reactor horizontal mid-plane is 27.5 ft (8.38 m) below the pool surface. The control plate drive mechanisms are located in a subpile room beneath the pressure vessel. These features provide the necessary shielding for working above the reactor core and greatly facilitate access to the pressure vessel, core, and reflector regions. In-core irradiation and experiment locations (cross section at horizontal midplane) Reactor core assembly Reactor core assembly: (1) in-core irradiation and experiment locations,

497

Experimental optimization of a free vortex propeller runner for micro hydro application  

SciTech Connect

The turbine technology for low head application in the micro hydro range has been vastly neglected despite niche available in scattered regions of valley flows as well as in wastewater canals and other energy recovery schemes, where the available head does not exceed 2 meters. The goal of this study is to develop hydraulically optimized propeller turbines for the micro hydro range with a particular focus on ease of manufacture. This paper presents a wide range of geometrical optimization steps carried out on a propeller runner, whose blades have been designed using the free vortex theory, and operating with a gross head from 1.5 to 2 m and discharge of approximately 75 l/s. It further illustrates 3 stages of geometrical modifications carried out on the runner with an objective of optimizing the runner performance. These modifications comprised of changes to the tip angles (both at the runner inlet and exit) as well as the hub angles (at the runner inlet) of the runner blades. The paper also presents an interesting theoretical methodology to analyze the effects of each optimization stage. This method looks at the relative changes to shaft power and discharge at constant head and speed and gives wonderful insight as to how the internal parameters like Euler shaft work and runner hydraulic losses are behaving with respect to each optimization stage. It was found that the performance of the runner was very sensitive to changes to exit tip angle. At two levels of modification, the discharge increased in the range of 15-30%, while shaft power increased in the range of 12-45%, thus influencing the efficiency characteristics. The results of the runner inlet tip modification were very interesting in that a very significant rise of turbine efficiency was recorded from 55% to 74% at the best efficiency point, which was caused by a reduced discharge consumption as well as a higher power generation. It was also found that the optimization study on a propeller runner has reasonably validated the estimates of the free vortex theory despite small deviations. The final runner configuration demonstrated a maximum efficiency of 74% ({+-}1.8%), which is very encouraging from the perspectives of micro hydro application. The paper concludes with recommendations of a series of optimization steps to increase the efficiency of the runner. It also recommends the attempt of Computational Fluid Dynamics both as a validation and optimization tool for future research on propeller runners. (author)

Singh, Punit; Nestmann, Franz [Institute for Water and River Basin Management (IWG), University of Karlsruhe, Kaiser Str. 12, D 76128 Karlsruhe (Germany)

2009-09-15T23:59:59.000Z

498

SECA Core Technology Program Seal Workshop  

NLE Websites -- All DOE Office Websites (Extended Search)

SECA Core Technology Program Seal Workshop Workshop held at Hyatt Regency, San Antonio August 10, 2007 Workshop organized by: Dr. Ayyakkannu Manivannan, National Energy technology Laboratory Morgantown, WV Dr. Prabhakar Singh Pacific Northwest National Laboratory Richland, WA 1 2 Table of Content * Executive Summary * Meeting Agenda * Presentations * List of Attendees 3 Executive Summary SECA Core Technology Program (SECA CTP) led workshop on the topical area titled "SOFC seal: Technology, Challenges and Future Directions" was held on August 10, 2007 at Hyatt Regency, San Antonio, TX. The workshop was attended by scientists and engineers presently involved in the development, engineering, fabrication, and testing of

499

Thermal metastabilities in the solar core  

E-Print Network (OSTI)

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

Attila Grandpierre; Gabor Agoston

2002-01-18T23:59:59.000Z

500

Wind reversals in turbulent Rayleigh-Benard convection  

E-Print Network (OSTI)

The phenomenon of irregular cessation and subsequent reversal of the large-scale circulation in turbulent Rayleigh-B\\'enard convection is theoretically analysed. The force and thermal balance on a single plume detached from the thermal boundary layer yields a set of coupled nonlinear equations, whose dynamics is related to the Lorenz equations. For Prandtl and Rayleigh numbers in the range $10^{-2} \\leq \\Pr \\leq 10^{3}$ and $10^{7} \\leq \\Ra \\leq 10^{12}$, the model has the following features: (i) chaotic reversals may be exhibited at Ra $\\geq 10^{7}$; (ii) the Reynolds number based on the root mean square velocity scales as $\\Re_{rms} \\sim \\Ra^{[0.41 ... 0.47]}$ (depending on Pr), and as $\\Re_{rms} \\sim \\Pr^{-[0.66 ... 0.76]}$ (depending on Ra); and (iii) the mean reversal frequency follows an effective scaling law $\\omega / (\

Francisco Fontenele Araujo; S. Grossmann; D. Lohse

2005-08-29T23:59:59.000Z