Sample records for 400-ton yin-yang magnet

  1. [1] Akira Kageyama and Tetsuya Sato, The "Yin-Yang Grid": An Overset Grid in Spherical Geometry, to be published Geochem. Geophys. Geosyst., E-print: physics/0403123

    E-Print Network [OSTI]

    Jablonowski, Christiane

    , Conservative CIP transport in meteorological models, submitted to JSME International Journal, 2004 [5] R. Jakob results of introduced simulation code on Yin-Yang grid system with mass conservation. Furthermore, we will introduce conservation scheme of the total energy and potential enstrophy. Figure 8 shows that Rossby

  2. Linear Extrusion 400 Tons/Day Dry Solids Pump

    SciTech Connect (OSTI)

    Kenneth Sprouse; David Matthews

    2008-04-30T23:59:59.000Z

    Pratt & Whitney Rocketdyne (PWR) has developed an innovative gasifier concept that uses rocket engine experience to significantly improve gasifier performance, life, and cost compared to current state-of-the-art systems. The PWR gasifier concept uses a compact and highly efficient (>50%) dry solids pump that has excellent availability (>99.5%). PWR is currently developing this dry solids pump under a U.S. Department of Energy (DOE) cooperative agreement. The conceptual design on two dry solids pumps were completed under this agreement and one pump concept was selected for preliminary design. A preliminary design review (PDR) of the selected pump was presented on September 20, 2007 to PWR management and numerous technical specialists. Feedback from the PDR review team has been factored into the design and a Delta-PDR was held on April 9, 2008.

  3. An ancient Chinese wisdom for metabolic engineering: Yin-Yang (Journal

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem Not Found Item Not Found The itemAIR SEPARATION BYAbrasion andArticle) | DOE

  4. Pharmacogenomics and the Yin/Yang actions of ginseng: anti-tumor, angiomodulating and steroid-like activities of ginsenosides

    E-Print Network [OSTI]

    Yue, Patrick Ying Kit; Mak, Nai Ki; Cheng, Yuen Kit; Leung, Kar Wah; Ng, Tzi Bun; Fan, Tai-Ping; Yeung, Hin Wing; Wong, Ricky Ngok Shun

    2007-05-15T23:59:59.000Z

    , Tennis Court Road, CB2 1PD, UK and 5International Society for Chinese Medicine, A & C, 1st floor, Block 2, University of Macau, Av. Padre Tomas Pereira, Taipa, Macao SAR, China Email: Patrick Ying Kit Yue - patrick@hkbu.edu.hk; Nai Ki Mak - nkmak... 's sarcoma Neoplasms Psoriasis Ulcer Skin Dysfunctional uterine bleeding Endometriosis Neoplasms Placental insufficiency Cancer Reproductive system Rheumatoid arthritis Bones, joints Ulcer Cancer Crohn's disease Digestive systemPage 8 of 21 (page number...

  5. Bitmaps for a Digital Theory of Everything Raymond Aschheim

    E-Print Network [OSTI]

    German, Dan-Adrian

    , yin.yang= NKS08-Aschheim-DigitalToeSlides30.nb 5 #12;Multiplicative group of eight elements 6 NKS08 elements of the multiplicative group group8 generates 24 elements which are 3 families of eight products.yin = yin.yang So they are multiplicative generators of a 8 elements multiplicative group. group8 = : yin4

  6. Magnetic investigations

    SciTech Connect (OSTI)

    Bath, G.D.; Jahren, C.E.; Rosenbaum, J.G. [Geological Survey, Denver, CO (USA); Baldwin, M.J. [Fenix and Scisson, Inc., Mercury, NV (USA)

    1983-12-31T23:59:59.000Z

    Air and ground magnetic anomalies in the Climax stock area of the NTS help define the gross configuration of the stock and detailed configuration of magnetized rocks at the Boundary and Tippinip faults that border the stock. Magnetizations of geologic units were evaluated by measurements of magnetic properties of drill core, minimum estimates of magnetizations from ground magnetic anomalies for near surface rocks, and comparisons of measured anomalies with anomalies computed by a three-dimensional forward program. Alluvial deposits and most sedimentary rocks are nonmagnetic, but drill core measurements reveal large and irregular changes in magnetization for some quartzites and marbles. The magnetizations of quartz monzonite and granodiorite near the stock surface are weak, about 0.15 A/m, and increase at a rate of 0.00196 A/m/m to 1.55 A/m, at depths greater than 700 m (2300 ft). The volcanic rocks of the area are weakly magnetized. Aeromagnetic anomalies 850 m (2800 ft) above the stock are explained by a model consisting of five vertical prisms. Prisms 1, 2, and 3 represent the near surface outline of the stock, prism 4 is one of the models developed by Whitehill (1973), and prism 5 is modified from the model developed by Allingham and Zietz (1962). Most of the anomaly comes from unsampled and strongly-magnetized deep sources that could be either granite or metamorphosed sedimentary rocks. 48 refs., 23 figs., 3 tabs.

  7. Magnetic Field Safety Magnetic Field Safety

    E-Print Network [OSTI]

    McQuade, D. Tyler

    Magnetic Field Safety Training #12;Magnetic Field Safety Strong Magnetic Fields exist around energized magnets. High magnetic fields alone are a recognized hazard only for personnel with certain medical conditions such as pacemakers, magnetic implants, or embedded shrapnel. In addition, high magnetic

  8. Strange Magnetism

    E-Print Network [OSTI]

    Thomas R. Hemmert; Ulf-G. Meissner; Sven Steininger

    1998-11-09T23:59:59.000Z

    We present an analytic and parameter-free expression for the momentum dependence of the strange magnetic form factor of the nucleon and its corresponding radius which has been derived in Heavy Baryon Chiral Perturbation Theory. We also discuss a model-independent relation between the isoscalar magnetic and the strange magnetic form factors of the nucleon based on chiral symmetry and SU(3) only. These limites are used to derive bounds on the strange magnetic moment of the proton from the recent measurement by the SAMPLE collaboration.

  9. Magnetic shielding

    DOE Patents [OSTI]

    Kerns, J.A.; Stone, R.R.; Fabyan, J.

    1985-02-12T23:59:59.000Z

    A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines.

  10. Magnetic nanotubes

    DOE Patents [OSTI]

    Matsui, Hiroshi (Glen Rock, NJ); Matsunaga, Tadashi (Tokyo, JP)

    2010-11-16T23:59:59.000Z

    A magnetic nanotube includes bacterial magnetic nanocrystals contacted onto a nanotube which absorbs the nanocrystals. The nanocrystals are contacted on at least one surface of the nanotube. A method of fabricating a magnetic nanotube includes synthesizing the bacterial magnetic nanocrystals, which have an outer layer of proteins. A nanotube provided is capable of absorbing the nanocrystals and contacting the nanotube with the nanocrystals. The nanotube is preferably a peptide bolaamphiphile. A nanotube solution and a nanocrystal solution including a buffer and a concentration of nanocrystals are mixed. The concentration of nanocrystals is optimized, resulting in a nanocrystal to nanotube ratio for which bacterial magnetic nanocrystals are immobilized on at least one surface of the nanotubes. The ratio controls whether the nanocrystals bind only to the interior or to the exterior surfaces of the nanotubes. Uses include cell manipulation and separation, biological assay, enzyme recovery, and biosensors.

  11. Magnets & Magnet Condensed Matter Science

    E-Print Network [OSTI]

    McQuade, D. Tyler

    18 No. 1 CONDENSED MATTER SCIENCE Technique development, graphene, magnetism & magnetic materials Pressure 9 Metal to Insulator Transition on the N=0 Landau Level in Graphene 10 Evidence for Fractional Quantum Hall States in Suspended Bilayer and Trilayer Graphene 11 Fractional Quantum Hall Effect

  12. Low dimensional magnetism

    E-Print Network [OSTI]

    Kjall, Jonas Alexander

    2012-01-01T23:59:59.000Z

    Magnetism in Ultracold Gases 4 Magnetic phase diagram of aMagnetism . . . . . . . . . . . .1.3 Magnetism in condensedIntroduction 1 Brief introduction to magnetism 1.1 Classic

  13. Controlling Magnetism at the Nanoscale

    E-Print Network [OSTI]

    Wong, Jared

    2012-01-01T23:59:59.000Z

    Manipulation of Magnetism - External148 Conclusion A The Magnetism Cheat Sheet A.1 Magnetic157 A.2 Magnetism Unit Conversion

  14. Neutrino magnetic moment in a magnetized plasma

    E-Print Network [OSTI]

    N. V. Mikheev; E. N. Narynskaya

    2010-11-08T23:59:59.000Z

    The contribution of a magnetized plasma to the neutrino magnetic moment is calculated. It is shown that only part of the additional neutrino energy in magnetized plasma connecting with its spin and magnetic field strength defines the neutrino magnetic moment. It is found that the presence of magnetized plasma does not lead to the considerable increase of the neutrino magnetic moment in contrast to the results presented in literature previously.

  15. Petroglyphs, Lighting, and Magnetism

    E-Print Network [OSTI]

    Walker, Merle F

    2007-01-01T23:59:59.000Z

    1950 Electricity and Magnetism: Theory and Applications.I Petroglyphs, Lightning, and Magnetism | Walker Figure 8.I Petroglyphs, Lightning, and Magnetism | Walker Figure IL

  16. Magnetic Catalysis vs Magnetic Inhibition

    E-Print Network [OSTI]

    Kenji Fukushima; Yoshimasa Hidaka

    2012-09-06T23:59:59.000Z

    We discuss the fate of chiral symmetry in an extremely strong magnetic field B. We investigate not only quark fluctuations but also neutral meson effects. The former would enhance the chiral-symmetry breaking at finite B according to the Magnetic Catalysis, while the latter would suppress the chiral condensate once B exceeds the scale of the hadron structure. Using a chiral model we demonstrate how neutral mesons are subject to the dimensional reduction and the low dimensionality favors the chiral-symmetric phase. We point out that this effect, the Magnetic Inhibition, can be a feasible explanation for recent lattice-QCD data indicating the decreasing behavior of the chiral-restoration temperature with increasing B.

  17. Magnetic Stereoscopy

    E-Print Network [OSTI]

    Thomas Wiegelmann; Bernd Inhester

    2006-12-21T23:59:59.000Z

    The space mission STEREO will provide images from two viewpoints. An important aim of the STEREO mission is to get a 3D view of the solar corona. We develop a program for the stereoscopic reconstruction of 3D coronal loops from images taken with the two STEREO spacecraft. A pure geometric triangulation of coronal features leads to ambiguities because the dilute plasma emissions complicates the association of features in image 1 with features in image 2. As a consequence of these problems the stereoscopic reconstruction is not unique and multiple solutions occur. We demonstrate how these ambiguities can be resolved with the help of different coronal magnetic field models (potential, linear and non-linear force-free fields). The idea is that, due to the high conductivity in the coronal plasma, the emitting plasma outlines the magnetic field lines. Consequently the 3D coronal magnetic field provides a proxy for the stereoscopy which allows to eliminate inconsistent configurations. The combination of stereoscopy and magnetic modelling is more powerful than one of these tools alone. We test our method with the help of a model active region and plan to apply it to the solar case as soon as STEREO data become available.

  18. Superconducting Magnet Division

    E-Print Network [OSTI]

    Superconducting Magnet Division DOE NP Program Review - July 06 1 Brookhaven Magnet Division - Nuclear Physics Program Support Activities Superconducting Magnet Program RHIC Operations Support Spin Summary Peter Wanderer, DOE review, July 25, 2006 Acting Head, Superconducting Magnet Division #12

  19. Magnetic Reconnection

    SciTech Connect (OSTI)

    Masaaki Yamada, Russell Kulsrud and Hantao Ji

    2009-09-17T23:59:59.000Z

    We review the fundamental physics of magnetic reconnection in laboratory and space plasmas, by discussing results from theory, numerical simulations, observations from space satellites, and the recent results from laboratory plasma experiments. After a brief review of the well-known early work, we discuss representative recent experimental and theoretical work and attempt to interpret the essence of significant modern findings. In the area of local reconnection physics, many significant findings have been made with regard to two- uid physics and are related to the cause of fast reconnection. Profiles of the neutral sheet, Hall currents, and the effects of guide field, collisions, and micro-turbulence are discussed to understand the fundamental processes in a local reconnection layer both in space and laboratory plasmas. While the understanding of the global reconnection dynamics is less developed, notable findings have been made on this issue through detailed documentation of magnetic self-organization phenomena in fusion plasmas. Application of magnetic reconnection physics to astrophysical plasmas is also brie y discussed.

  20. Patterned Magnetic Nanostructures and Quantized Magnetic Disks

    E-Print Network [OSTI]

    -increasing demands in data storage and to new applications of magnetic devices in the field of sensors. NewPatterned Magnetic Nanostructures and Quantized Magnetic Disks STEPHEN Y. CHOU Invited Paper, opens up new opportunities for engineering innovative magnetic materials and devices, developing ultra

  1. An optimized magnet for magnetic refrigeration

    E-Print Network [OSTI]

    Bjørk, R; Smith, A; Christensen, D V; Pryds, N

    2014-01-01T23:59:59.000Z

    A magnet designed for use in a magnetic refrigeration device is presented. The magnet is designed by applying two general schemes for improving a magnet design to a concentric Halbach cylinder magnet design and dimensioning and segmenting this design in an optimum way followed by the construction of the actual magnet. The final design generates a peak value of 1.24 T, an average flux density of 0.9 T in a volume of 2 L using only 7.3 L of magnet, and has an average low flux density of 0.08 T also in a 2 L volume. The working point of all the permanent magnet blocks in the design is very close to the maximum energy density. The final design is characterized in terms of a performance parameter, and it is shown that it is one of the best performing magnet designs published for magnetic refrigeration.

  2. Superconducting Magnet Division

    E-Print Network [OSTI]

    Gupta, Ramesh

    Superconducting Magnet Division Permanent Magnet Designs with Large Variations in Field Strength the residual field of the magnetized bricks by concentrating flux lines at the iron pole. Low Field Design Medium Field Design Superconducting Magnet Division Dipole and Quadrupole Magnets for RHIC e

  3. Superconducting magnet

    DOE Patents [OSTI]

    Satti, John A. (Naperville, IL)

    1980-01-01T23:59:59.000Z

    A superconducting magnet designed to produce magnetic flux densities of the order of 4 to 5 Webers per square meter is constructed by first forming a cable of a plurality of matrixed superconductor wires with each wire of the plurality insulated from each other one. The cable is shaped into a rectangular cross-section and is wound with tape in an open spiral to create cooling channels. Coils are wound in a calculated pattern in saddle shapes to produce desired fields, such as dipoles, quadrupoles, and the like. Wedges are inserted between adjacent cables as needed to maintain substantially radial placement of the long dimensions of cross sections of the cables. After winding, individual strands in each of the cables are brought out to terminals and are interconnected to place all of the strands in series and to maximize the propagation of a quench by alternating conduction from an inner layer to an outer layer and from top half to bottom half as often as possible. Individual layers are separated from others by spiraled aluminum spacers to facilitate cooling. The wound coil is wrapped with an epoxy tape that is cured by heat and then machined to an interference fit with an outer aluminum pipe which is then affixed securely to the assembled coil by heating it to make a shrink fit. In an alternate embodiment, one wire of the cable is made of copper or the like to be heated externally to propagate a quench.

  4. Nanostructured magnetic materials

    E-Print Network [OSTI]

    Chan, Keith T.

    2011-01-01T23:59:59.000Z

    Magnetism and Magnetic Materials Conference, Atlanta, GA (Nanostructured Magnetic Materials by Keith T. Chan Doctor ofinduced by a Si-based material occurs at a Si/Ni interface

  5. Interface Magnetism in Multiferroics

    E-Print Network [OSTI]

    He, Qing

    2011-01-01T23:59:59.000Z

    1.2.1 Magnetism . . . . . . . . . . . . . . . . . . . 1.2.2domain walls . . . . . 3 Magnetism of domain walls in BiFeOof electrical control of magnetism in mixed phase BiFeO 3

  6. Laced permanent magnet quadrupole drift tube magnets

    SciTech Connect (OSTI)

    Feinberg, B.; Behrsing, G.U.; Halbach, K.; Marks, J.S.; Morrison, M.E.; Nelson, D.H.

    1989-03-01T23:59:59.000Z

    Twenty-three laced permanent magnet quadrupole drift tube magnets have been constructed, tested, and installed in the SuperHILAC heavy ion linear accelerator at LBL, marking the first accelerator use of this new type of quadrupole. The magnets consist of conventional tape-wound quadrupole electromagnets, using iron pole-pieces, with permanent magnet material (samarium cobalt) inserted between the poles to reduce the effects of saturation. The iron is preloaded with magnetic flux generated by the permanent magnet material, resulting in an asymmetrical saturation curve. Since the polarity of the individual quadrupole magnets in a drift tube linac is never reversed, we can take advantage of this asymmetrical saturation to provide about 20% greater focusing strength than is available with conventional quadrupoles, while replacing the vanadium permendur poletips with iron poletips. Comparisons between these magnets and conventional tape-wound quadrupoles will be presented. 3 refs., 5 figs.

  7. SUPERCONDUCTING MAGNETIC ENERGY STORAGE

    E-Print Network [OSTI]

    Hassenzahl, W.

    2011-01-01T23:59:59.000Z

    Superconducting 30-MJ Energy Storage Coil", Proc. 19 80 ASC,Superconducting Magnetic Energy Storage Plant", IEEE Trans.SlIperconducting Magnetic Energy Storage Unit", in Advances

  8. SUPERCONDUCTING MAGNETIC ENERGY STORAGE

    E-Print Network [OSTI]

    Hassenzahl, W.

    2011-01-01T23:59:59.000Z

    Design of the BPA Superconducting 30-MJ Energy Storagefor a Utility Scale Superconducting Magnetic Energy Storagefor a Lnrge Scale Superconducting Magnetic Energy Storage

  9. Laced permanent magnet quadrupole drift tube magnets

    SciTech Connect (OSTI)

    Feinberg, B.; Behrsing, G.U.; Halbach, K.; Marks, J.S.; Morrison, M.E.; Nelson, D.H.

    1988-10-01T23:59:59.000Z

    A laced permanent magnet quadrupole drift tube magnet has been constructed for a proof-of-principle test. The magnet is a conventional tape-wound quadrupole electromagnet, using iron pole- pieces, with the addition of permanent magnet material (neodymium iron) between the poles to reduce the effects of saturation. The iron is preloaded with magnetic flux generated by the permanent magnet material, resulting in an asymmetrical saturation curve. Since the polarity of the quadrupole magnets in a drift tube linac is not reversed we can take advantage of this asymmetrical saturation to provide greater focusing strength. The magnet configuration has been optimized and the vanadium permendur poles needed in a conventional quadrupole have been replaced with iron poles. The use of permanent magnet material has allowed us to increase the focusing strength of the magnet by about 20% over that of a conventional tape-wound quadrupole. Comparisons will be made between this magnet and the conventional tape-wound quadrupole. 3 refs., 5 figs.

  10. Introduction Magnetic Anisotropy of

    E-Print Network [OSTI]

    Rossak, Wilhelm R.

    not completely understood interesting for dilute magnetic semiconductors (DMSs) transparent ferromagnets

  11. Magnetic Imaging Wolfgang Kuch

    E-Print Network [OSTI]

    Kuch, Wolfgang

    Magnetic Imaging Wolfgang Kuch Freie Universit¨at Berlin, Institut f¨ur Experimentalphysik, Arnimallee 14, 14195 Berlin, Germany kuch@physik.fu-berlin.de Abstract. Imaging of magnetic domains has- ern techniques is used nowadays routinely for magnetic imaging of magnetic ma- terials

  12. Superconducting Magnet Division

    E-Print Network [OSTI]

    McDonald, Kirk

    Superconducting Magnet Division Ramesh Gupta 20T Target Solenoid with HTS Insert Solenoid Capture Laboratory New York, USA http://www.bnl.gov/magnets/staff/gupta #12;Superconducting Magnet Division Ramesh of HTS may significantly reduce the amount of Tungsten shielding · Summary #12;Superconducting Magnet

  13. Nanocomposite Magnets: Transformational Nanostructured Permanent Magnets

    SciTech Connect (OSTI)

    None

    2010-10-01T23:59:59.000Z

    Broad Funding Opportunity Announcement Project: GE is using nanomaterials technology to develop advanced magnets that contain fewer rare earth materials than their predecessors. Nanomaterials technology involves manipulating matter at the atomic or molecular scale, which can represent a stumbling block for magnets because it is difficult to create a finely grained magnet at that scale. GE is developing bulk magnets with finely tuned structures using iron-based mixtures that contain 80% less rare earth materials than traditional magnets, which will reduce their overall cost. These magnets will enable further commercialization of HEVs, EVs, and wind turbine generators while enhancing U.S. competitiveness in industries that heavily utilize these alternatives to rare earth minerals.

  14. Magnetic infrasound sensor

    DOE Patents [OSTI]

    Mueller, Fred M. (Los Alamos, NM); Bronisz, Lawrence (Los Alamos, NM); Grube, Holger (Los Alamos, NM); Nelson, David C. (Santa Fe, NM); Mace, Jonathan L. (Los Alamos, NM)

    2006-11-14T23:59:59.000Z

    A magnetic infrasound sensor is produced by constraining a permanent magnet inside a magnetic potential well above the surface of superconducting material. The magnetic infrasound sensor measures the position or movement of the permanent magnet within the magnetic potential well, and interprets the measurements. Infrasound sources can be located and characterized by combining the measurements from one or more infrasound sensors. The magnetic infrasound sensor can be tuned to match infrasound source types, resulting in better signal-to-noise ratio. The present invention can operate in frequency modulation mode to improve sensitivity and signal-to-noise ratio. In an alternate construction, the superconductor can be levitated over a magnet or magnets. The system can also be driven, so that time resolved perturbations are sensed, resulting in a frequency modulation version with improved sensitivity and signal-to-noise ratio.

  15. Tamper resistant magnetic stripes

    DOE Patents [OSTI]

    Naylor, Richard Brian (Albuquerque, NM); Sharp, Donald J. (Albuquerque, NM)

    1999-01-01T23:59:59.000Z

    This invention relates to a magnetic stripe comprising a medium in which magnetized particles are suspended and in which the encoded information is recorded by actual physical rotation or alignment of the previously magnetized particles within the flux reversals of the stripe which are 180.degree. opposed in their magnetic polarity. The magnetized particles are suspended in a medium which is solid, or physically rigid, at ambient temperatures but which at moderately elevated temperatures, such as 40.degree. C., is thinable to a viscosity permissive of rotation of the particles therein under applications of moderate external magnetic field strengths within acceptable time limits.

  16. Journal of Magnetism and Magnetic Materials ] (

    E-Print Network [OSTI]

    McHenry, Michael E.

    magnetic properties were measured with a vibrating sample magnetometer. The mass-specific power loss.40.Rs Keywords: Nanocrystalline alloys; Amorphous alloys; Field annealing; Power loss; Soft magnets the hysteretic power loss while maintaining high-temperature operability [4]. Other goals have included studies

  17. Magnetic Materials Group

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

    for magnetic circular dichroism (XMCD) and magnetic scattering experiments. Sunset Yellow 6-ID-B: Resonant and In-Field Scattering Beamline 6-ID-B,C is the primary beamline on...

  18. Recent lunar magnetism

    E-Print Network [OSTI]

    Buz, Jennifer

    2011-01-01T23:59:59.000Z

    The magnetization of young lunar samples (magnetic fields (e.g. core dynamo and long-lived impact plasma fields) have not been present within the last 1.5 Ga. To better ...

  19. Active magnetic regenerator

    DOE Patents [OSTI]

    Barclay, John A. (Los Alamos, NM); Steyert, William A. (Los Alamos, NM)

    1982-01-01T23:59:59.000Z

    The disclosure is directed to an active magnetic regenerator apparatus and method. Brayton, Stirling, Ericsson, and Carnot cycles and the like may be utilized in an active magnetic regenerator to provide efficient refrigeration over relatively large temperature ranges.

  20. Magnetism Theory Group / POSTECH Magnetism Theory Group / POSTECH

    E-Print Network [OSTI]

    Min, Byung Il

    Magnetism Theory Group / POSTECH #12;Magnetism Theory Group / POSTECH #12;Magnetism Theory Group / POSTECH #12;Magnetism Theory Group / POSTECH #12;Magnetism Theory Group / POSTECH J.H . Park et al. #12;'s of FeinCsm e tal The chargeandorbitalordering geom etryin YB a C o 2 O 5 S. K. Kwon etal .Magnetism Theory

  1. Magnetic susceptibility in QCD

    E-Print Network [OSTI]

    V. D. Orlovsky; Yu. A. Simonov

    2014-05-12T23:59:59.000Z

    Magnetic susceptibility in the deconfined phase of QCD is calculated in a closed form using a recent general expression for the quark gas pressure in magnetic field. Quark selfenergies are entering the result via Polyakov line factors and ensure the total paramagnetic effect, increasing with temperature. A generalized form of magnetic susceptibility in nonzero magnetic field suitable for experimental and lattice measurements is derived, showing a good agreement with available lattice data.

  2. Noble gas magnetic resonator

    DOE Patents [OSTI]

    Walker, Thad Gilbert; Lancor, Brian Robert; Wyllie, Robert

    2014-04-15T23:59:59.000Z

    Precise measurements of a precessional rate of noble gas in a magnetic field is obtained by constraining the time averaged direction of the spins of a stimulating alkali gas to lie in a plane transverse to the magnetic field. In this way, the magnetic field of the alkali gas does not provide a net contribution to the precessional rate of the noble gas.

  3. Magnetic nanohole superlattices

    DOE Patents [OSTI]

    Liu, Feng

    2013-05-14T23:59:59.000Z

    A magnetic material is disclosed including a two-dimensional array of carbon atoms and a two-dimensional array of nanoholes patterned in the two-dimensional array of carbon atoms. The magnetic material has long-range magnetic ordering at a temperature below a critical temperature Tc.

  4. Magnetically attached sputter targets

    DOE Patents [OSTI]

    Makowiecki, D.M.; McKernan, M.A.

    1994-02-15T23:59:59.000Z

    An improved method and assembly for attaching sputtering targets to cathode assemblies of sputtering systems which includes a magnetically permeable material is described. The magnetically permeable material is imbedded in a target base that is brazed, welded, or soldered to the sputter target, or is mechanically retained in the target material. Target attachment to the cathode is achieved by virtue of the permanent magnets and/or the pole pieces in the cathode assembly that create magnetic flux lines adjacent to the backing plate, which strongly attract the magnetically permeable material in the target assembly. 11 figures.

  5. The chiral magnetic nanomotors

    E-Print Network [OSTI]

    Morozov, Konstantin I

    2013-01-01T23:59:59.000Z

    Propulsion of the chiral magnetic nanomotors powered by a rotating magnetic field is in the focus of the modern biomedical applications. This technology relies on strong interaction of dynamic and magnetic degrees of freedom of the system. Here we study in detail various experimentally observed regimes of the helical nanomotor orientation and propulsion depending on the actuation frequency, and establish the relation of these two properties with remanent magnetization and geometry of the helical nanomotors. The theoretical predictions for the transition between the regimes and nanomotor orientation and propulsion speed are in excellent agreement with available experimental data. The proposed theory offers a few simple guidelines towards the optimal design of the magnetic nanomotors. In particular, efficient nanomotors should be fabricated of hard magnetics, e.g., cobalt, magnetized transversally and have the geometry of a normal helix with a helical angle of 35-45 degrees.

  6. Passive magnetic bearing system

    DOE Patents [OSTI]

    Post, Richard F.

    2014-09-02T23:59:59.000Z

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

  7. Pulse magnetic welder

    DOE Patents [OSTI]

    Christiansen, D.W.; Brown, W.F.

    1984-01-01T23:59:59.000Z

    A welder is described for automated closure of fuel pins by a pulsed magnetic process in which the open end of a length of cladding is positioned within a complementary tube surrounded by a pulsed magnetic welder. Seals are provided at each end of the tube, which can be evacuated or can receive tag gas for direct introduction to the cladding interior. Loading of magnetic rings and end caps is accomplished automatically in conjunction with the welding steps carried out within the tube.

  8. Magnetic latching solenoid

    DOE Patents [OSTI]

    Marts, Donna J. (Idaho Falls, ID); Richardson, John G. (Idaho Falls, ID); Albano, Richard K. (Idaho Falls, ID); Morrison, Jr., John L. (Idaho Falls, ID)

    1995-01-01T23:59:59.000Z

    This invention discloses a D.C. magnetic latching solenoid that retains a moving armature in a first or second position by means of a pair of magnets, thereby having a zero-power requirement after actuation. The first or second position is selected by reversing the polarity of the D.C. voltage which is enough to overcome the holding power of either magnet and transfer the armature to an opposite position. The coil is then de-energized.

  9. Holographic Magnetic Phase Transition

    E-Print Network [OSTI]

    Gilad Lifschytz; Matthew Lippert

    2009-06-21T23:59:59.000Z

    We study four-dimensional interacting fermions in a strong magnetic field, using the holographic Sakai-Sugimoto model of intersecting D4 and D8 branes in the deconfined, chiral-symmetric parallel phase. We find that as the magnetic field is varied, while staying in the parallel phase, the fermions exhibit a first-order phase transition in which their magnetization jumps discontinuously. Properties of this transition are consistent with a picture in which some of the fermions jump to the lowest Landau level. Similarities to known magnetic phase transitions are discussed.

  10. Magnetic Braids Anthony Yeates

    E-Print Network [OSTI]

    Dundee, University of

    flux function Main result Conclusion 2. Thermonuclear confinement devices. ITER (Internat'l Thermonuclear Experimental Reactor). Inside the KSTAR tokamak. Correspond to periodic magnetic braids. 4 / 22

  11. Charge and magnetization inhomogeneities in diluted magnetic semiconductors

    E-Print Network [OSTI]

    Timm, Carsten

    2006-03-01T23:59:59.000Z

    It is predicted that III-V diluted magnetic semiconductors can exhibit stripelike modulations of magnetization and carrier concentration. This inhomogeneity results from the strong dependence of the magnetization on the carrier concentration. Within...

  12. Journal of Magnetism and Magnetic Materials 252 (2002) 159161 Magnetically induced alignment of FNS

    E-Print Network [OSTI]

    Reznikov, Yuri

    Journal of Magnetism and Magnetic Materials 252 (2002) 159­161 Magnetically induced alignment the observation of magnetically controlled anchoring of ferro-nematic suspensions. We found that application of a weak magnetic field to a cell with the ferro-suspension induces an easy orientation axis with weak

  13. High Temperature, Permanent Magnet Biased Magnetic Bearings

    E-Print Network [OSTI]

    Gandhi, Varun R.

    2010-07-14T23:59:59.000Z

    , then the molding process was carried out to form the potting cement on the each stator. After this the stators are baked in the oven and once ready the magnets and back-irons are put onto the stator. Shown below in Figure 3-11 is an assembly tool designed... rings. The bearing and its support rings were then carried onto the test rig and mounted at one end of the table. Throughout the assembly process a lot of care had to be taken so as to avoid damaging of the permanent magnets, stator and its coils...

  14. Magnetic Gas Sensing Using a Dilute Magnetic Semiconductor. ...

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

    Abstract: The authors report on a magnetic gas sensing methodology to detect hydrogen using the ferromagnetic properties of a nanoscale dilute magnetic semiconductor...

  15. Superconducting Magnet Division

    E-Print Network [OSTI]

    Ohta, Shigemi

    Superconducting Magnet Division MAGNETIC DESIGN OF E-LENS SOLENOID AND CORRECTOR SYSTEM FOR RHIC* R.6 A gun collectors gun Combined Horizontal and Vertical Corrector Design Both types of dipole correctors. Gupta, M. Anerella, W. Fischer, G. Ganetis, X. Gu, A. Ghosh, A. Jain, P. Kovach, A. Marone, S. Plate, A

  16. Passive magnetic bearing configurations

    DOE Patents [OSTI]

    Post, Richard F. (Walnut Creek, CA)

    2011-01-25T23:59:59.000Z

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

  17. Active Magnetic Regenerator Experimental Optimization

    E-Print Network [OSTI]

    Victoria, University of

    the potential to create more efficient and compact refrigeration devices is an Active Magnetic Regenerative temperature refrigerators, as well as efficient gas liquefaction plants (AMRLs). Active Magnetic Regenerator Refrigeration exploits the magnetocaloric effect displayed by magnetic materials whereby a reversible

  18. Review and comparison of magnet designs for magnetic refrigeration

    E-Print Network [OSTI]

    Bjørk, R; Smith, A; Pryds, N

    2014-01-01T23:59:59.000Z

    One of the key issues in magnetic refrigeration is generating the magnetic field that the magnetocaloric material must be subjected to. The magnet constitutes a major part of the expense of a complete magnetic refrigeration system and a large effort should therefore be invested in improving the magnet design. A detailed analysis of the efficiency of different published permanent magnet designs used in magnetic refrigeration applications is presented in this paper. Each design is analyzed based on the generated magnetic flux density, the volume of the region where this flux is generated and the amount of magnet material used. This is done by characterizing each design by a figure of merit magnet design efficiency parameter, $\\Lambda_\\mathrm{cool}$. The designs are then compared and the best design found. Finally recommendations for designing the ideal magnet design are presented based on the analysis of the reviewed designs.

  19. Condensed Matter and Magnet Science

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

    and HC) Suite of nondestructive pulsed magnets up to 100 tesla Thermoacoustics and fluid dynamics Transport, magnetism, and thermodynamic characterization at extreme conditions of...

  20. QUENCHES IN LARGE SUPERCONDUCTING MAGNETS

    E-Print Network [OSTI]

    Eberhard, P.H.

    2010-01-01T23:59:59.000Z

    QUENCHES IN LARGE SUPERCONDUCTING MAGNETS. P. H. Eberhard,Study of an Unprotected Superconducting Coil Going Normal,"Method for Testing Superconducting Magnets," LBL Physics

  1. Large Magnetization at Carbon Surfaces

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

    Large Magnetization at Carbon Surfaces Large Magnetization at Carbon Surfaces Print Wednesday, 31 August 2011 00:00 From organic matter to pencil lead, carbon is a versatile...

  2. Journal of Magnetism and Magnetic Materials ] (

    E-Print Network [OSTI]

    Schumann, Rolf

    width of internal field fluctuations. For the ``normal'' TR of the metallic magnets SmCo5; Sm2Co17 of the parameters for SmCo5 and barium ferrite. Susceptibility measurements with small alternating fields, carried out at different points of the TR curve, as well as repeating TR-experiments at SmCo5 demonstrate

  3. Permanent magnet energy conversion machine with magnet mounting arrangement

    DOE Patents [OSTI]

    Hsu, John S. (Oak Ridge, TN); Adams, Donald J. (Knoxville, TN)

    1999-01-01T23:59:59.000Z

    A hybrid permanent magnet dc motor includes three sets of permanent magnets supported by the rotor and three sets of corresponding stators fastened to the surrounding frame. One set of magnets operates across a radial gap with a surrounding radial gap stator, and the other two sets of magnets operate off the respective ends of the rotor across respective axial gaps.

  4. Magnetic Resonance Imaging System Based on Earth's Magnetic Field

    E-Print Network [OSTI]

    Stepi?nik, Janez

    Magnetic Resonance Imaging System Based on Earth's Magnetic Field Ales Mohoric,1,* Gorazd Planinsic magnetic field can be partly compensated by the receiving coil design and shielding of electromagnetic pick and must be monitored accurately.[8­ 10] The importance of NMR in a non-uniform magnetic field

  5. Moment free toroidal magnet

    DOE Patents [OSTI]

    Bonanos, Peter (East Brunswick, NJ)

    1983-01-01T23:59:59.000Z

    A toroidal magnet for confining a high magnetic field for use in fusion reactor research and nuclear particle detection. The magnet includes a series of conductor elements arranged about and fixed at its small major radius portion to the outer surface of a central cylindrical support each conductor element having a geometry such as to maintain the conductor elements in pure tension when a high current flows therein, and a support assembly which redistributes all or part of the tension which would otherwise arise in the small major radius portion of each coil element to the large major radius portion thereof.

  6. Modular tokamak magnetic system

    DOE Patents [OSTI]

    Yang, Tien-Fang (Wayland, MA)

    1988-01-01T23:59:59.000Z

    A modular tokamak system comprised of a plurality of interlocking moldules. Each module is comprised of a vacuum vessel section, a toroidal field coil, moldular saddle coils which generate a poloidal magnetic field and ohmic heating coils.

  7. Geometrically frustrated quantum magnets

    E-Print Network [OSTI]

    Nikolić , Predrag, 1974-

    2004-01-01T23:59:59.000Z

    (cont.) more general lessons on frustrated quantum magnetism. At the end, we demonstrate some new mathematical tools on two other frustrated two-dimensional systems, and summarize our conclusions, with an outlook to remaining ...

  8. Ultrafast Magnetic Light

    E-Print Network [OSTI]

    Makarov, Sergey V; Krasnok, Alexander E; Belov, Pavel A

    2015-01-01T23:59:59.000Z

    We propose a novel concept for efficient dynamic tuning of optical properties of a high refractive index subwavelength nanoparticle with a magnetic Mie-type resonance by means of femtosecond laser radiation. This concept is based on ultrafast generation of electron-hole plasma within such nanoparticle, drastically changing its transient dielectric permittivity. This allows to manipulate by both electric and magnetic nanoparticle responses, resulting in dramatic changes of its extinction cross section and scattering diagram. Specifically, we demonstrate the effect of ultrafast switching-on a Huygens source in the vicinity of the magnetic dipole resonance. This approach enables to design ultrafast and compact optical switchers and modulators based on the "ultrafast magnetic light" concept.

  9. Magnetic gripper device

    DOE Patents [OSTI]

    Meyer, Ross E. (Los Alamos, NM)

    1993-01-01T23:59:59.000Z

    A climbing apparatus is provided for climbing ferromagnetic surfaces, such as storage tanks and steel frame structures. A magnet assembly is rotatably mounted in a frame assembly. The frame assembly provides a pair of cam surfaces having different dimensions so that, when the frame is rotated, the cam surfaces contact the ferromagnetic surface to separate the magnet assembly from the surface. The different cam dimensions enable one side of the magnet at a time to be detached from the surface to reduce the effort needed to disengage the climbing apparatus. The cam surface also provides for smoothly attaching the apparatus. A hardened dowel pin is also attached to the frame and the pointed end of the dowel engages the surface when the magnet is attached to the surface to prevent downward sliding movement of the assembly under the weight of the user.

  10. Magnetic gripper device

    DOE Patents [OSTI]

    Meyer, R.E.

    1993-03-09T23:59:59.000Z

    A climbing apparatus is provided for climbing ferromagnetic surfaces, such as storage tanks and steel frame structures. A magnet assembly is rotatably mounted in a frame assembly. The frame assembly provides a pair of cam surfaces having different dimensions so that, when the frame is rotated, the cam surfaces contact the ferromagnetic surface to separate the magnet assembly from the surface. The different cam dimensions enable one side of the magnet at a time to be detached from the surface to reduce the effort needed to disengage the climbing apparatus. The cam surface also provides for smoothly attaching the apparatus. A hardened dowel pin is also attached to the frame and the pointed end of the dowel engages the surface when the magnet is attached to the surface to prevent downward sliding movement of the assembly under the weight of the user.

  11. Magnetic susceptibility, magnetization, magnetic moment and characterization of Carancas meteorite

    E-Print Network [OSTI]

    Rosales, Domingo

    2015-01-01T23:59:59.000Z

    On September, 15th, 2007, in the community of Carancas (Puno, Peru) a stony meteorite formed a crater explosive type with a mean diameter of 13.5 m. some samples meteorite fragments were collected. The petrologic analysis performed corresponds to a meteorite ordinary chondrite H 4-5. In this paper we have analyzed the magnetic properties of a meteorite fragment with a proton magnetometer. Also in order to have a complete characterization of the Carancas meteorite and its crater, from several papers, articles and reports, we have made a compilation of the most important characteristics and properties of this meteorite.

  12. Engineering problems of tandem-mirror reactors

    SciTech Connect (OSTI)

    Moir, R.W.; Barr, W.L.; Boghosian, B.M.

    1981-10-22T23:59:59.000Z

    We have completed a comparative evaluation of several end plug configurations for tandem mirror fusion reactors with thermal barriers. The axi-cell configuration has been selected for further study and will be the basis for a detailed conceptual design study to be carried out over the next two years. The axi-cell end plug has a simple mirror cell produced by two circular coils followed by a transition coil and a yin-yang pair, which provides for MHD stability. This paper discusses some of the many engineering problems facing the designer. We estimated the direct cost to be 2$/W/sub e/. Assuming total (direct and indirect) costs to be twice this number, we need to reduce total costs by factors between 1.7 and 2.3 to compete with future LWRs levelized cost of electricity. These reductions may be possible by designing magnets producing over 20T made possible by use of combinations of superconducting and normal conducting coils as well as improvements in performance and cost of neutral beam and microwave power systems. Scientific and technological understanding and innovation are needed in the area of thermal barrier pumping - a process by which unwanted particles are removed (pumped) from certain regions of velocity and real space in the end plug. Removal of exhaust fuel ions, fusion ash and impurities by action of a halo plasma and plasma dump in the mirror end region is another challenging engineering problem discussed in this paper.

  13. Permanent Magnet Ecr Plasma Source With Magnetic Field Optimization

    DOE Patents [OSTI]

    Doughty, Frank C. (Plano, TX); Spencer, John E. (Plano, TX)

    2000-12-19T23:59:59.000Z

    In a plasma-producing device, an optimized magnet field for electron cyclotron resonance plasma generation is provided by a shaped pole piece. The shaped pole piece adjusts spacing between the magnet and the resonance zone, creates a convex or concave resonance zone, and decreases stray fields between the resonance zone and the workpiece. For a cylindrical permanent magnet, the pole piece includes a disk adjacent the magnet together with an annular cylindrical sidewall structure axially aligned with the magnet and extending from the base around the permanent magnet. The pole piece directs magnetic field lines into the resonance zone, moving the resonance zone further from the face of the magnet. Additional permanent magnets or magnet arrays may be utilized to control field contours on a local scale. Rather than a permeable material, the sidewall structure may be composed of an annular cylindrical magnetic material having a polarity opposite that of the permanent magnet, creating convex regions in the resonance zone. An annular disk-shaped recurve section at the end of the sidewall structure forms magnetic mirrors keeping the plasma off the pole piece. A recurve section composed of magnetic material having a radial polarity forms convex regions and/or magnetic mirrors within the resonance zone.

  14. Magnetic coupling device

    DOE Patents [OSTI]

    Nance, Thomas A. (Aiken, SC)

    2009-08-18T23:59:59.000Z

    A quick connect/disconnect coupling apparatus is provided in which a base member is engaged by a locking housing through a series of interengagement pins. The pins maintain the shaft in a locked position. Upon exposure to an appropriately positioned magnetic field, pins are removed a sufficient distance such that the shaft may be withdrawn from the locking housing. The ability to lock and unlock the connector assembly requires no additional tools or parts apart from a magnetic key.

  15. Magnetic fluorescent lamp

    DOE Patents [OSTI]

    Berman, S.M.; Richardson R.W.

    1983-12-29T23:59:59.000Z

    The radiant emission of a mercury-argon discharge in a fluorescent lamp assembly is enhanced by providing means for establishing a magnetic field with lines of force along the path of electron flow through the bulb of the lamp assembly, to provide Zeeman splitting of the ultraviolet spectral line. Optimum results are obtained when the magnetic field strength causes a Zeeman splitting of approximately 1.7 times the thermal line width.

  16. Freely oriented portable superconducting magnet

    DOE Patents [OSTI]

    Schmierer, Eric N. (Los Alamos, NM); Prenger, F. Coyne (Los Alamos, NM); Hill, Dallas D. (Los Alamos, NM)

    2010-01-12T23:59:59.000Z

    A freely oriented portable superconducting magnet is disclosed. Coolant is supplied to the superconducting magnet from a repository separate from the magnet, enabling portability of the magnet. A plurality of support assemblies structurally anchor and thermally isolate the magnet within a thermal shield. A plurality of support assemblies structurally anchor and thermally isolate the thermal shield within a vacuum vessel. The support assemblies restrain movement of the magnet resulting from energizing and cooldown, as well as from changes in orientation, enabling the magnet to be freely orientable.

  17. Magnetic metallic multilayers

    SciTech Connect (OSTI)

    Hood, R.Q.

    1994-04-01T23:59:59.000Z

    Utilizing self-consistent Hartree-Fock calculations, several aspects of multilayers and interfaces are explored: enhancement and reduction of the local magnetic moments, magnetic coupling at the interfaces, magnetic arrangements within each film and among non-neighboring films, global symmetry of the systems, frustration, orientation of the various moments with respect to an outside applied field, and magnetic-field induced transitions. Magnetoresistance of ferromagnetic-normal-metal multilayers is found by solving the Boltzmann equation. Results explain the giant negative magnetoresistance encountered in these systems when an initial antiparallel arrangement is changed into a parallel configuration by an external magnetic field. The calculation depends on (1) geometric parameters (thicknesses of layers), (2) intrinsic metal parameters (number of conduction electrons, magnetization, and effective masses in layers), (3) bulk sample properties (conductivity relaxation times), (4) interface scattering properties (diffuse scattering versus potential scattering at the interfaces, and (5) outer surface scattering properties (specular versus diffuse surface scattering). It is found that a large negative magnetoresistance requires considerable asymmetry in interface scattering for the two spin orientations. Features of the interfaces that may produce an asymmetrical spin-dependent scattering are studied: varying interfacial geometric random roughness with no lateral coherence, correlated (quasi-periodic) roughness, and varying chemical composition of the interfaces. The interplay between these aspects of the interfaces may enhance or suppress the magnetoresistance, depending on whether it increases or decreases the asymmetry in the spin-dependent scattering of the conduction electrons.

  18. Magnetic monopole and the nature of the static magnetic field

    E-Print Network [OSTI]

    Xiuqing Huang

    2008-12-10T23:59:59.000Z

    We investigate the factuality of the hypothetical magnetic monopole and the nature of the static magnetic field. It is shown from many aspects that the concept of the massive magnetic monopoles clearly is physically untrue. We argue that the static magnetic field of a bar magnet, in fact, is the static electric field of the periodically quasi-one-dimensional electric-dipole superlattice, which can be well established in some transition metals with the localized d-electron. This research may shed light on the perfect unification of magnetic and electrical phenomena.

  19. Active magnetic regenerator

    DOE Patents [OSTI]

    Barclay, J.A.; Steyert, W.A.

    1981-01-27T23:59:59.000Z

    An apparatus and method for refrigeration are disclosed which provides efficient refrigeration over temperature ranges in excess of 20/sup 0/C and which requires no maintenance and is, therefore, usable on an unmanned satellite. The apparatus comprises a superconducting magnet which may be solenoidal. A piston comprising a substance such as a rare earth substance which is maintained near its Curie temperature reciprocates through the bore of the solenoidal magnet. A magnetic drive rod is connected to the piston and appropriate heat sinks are connected thereto. The piston is driven by a suitable mechanical drive such as an electric motor and cam. In practicing the invention, the body of the piston is magnetized and demagnetized as it moves through the magnetic field of the solenoid to approximate any of the following cycles or a condition thereof as well as, potentially, other cycles: Brayton, Carnot, Ericsson, and Stirling. Advantages of the present invention include: that refrigeration can be accomplished over at least a 20/sup 0/C scale at superconducting temperatures as well as at more conventional temperatures; very high efficiency, high reliability, and small size. (LCL)

  20. Frustrated Magnetism in Low-Dimensional Lattices

    E-Print Network [OSTI]

    Tovar, Mayra

    2011-01-01T23:59:59.000Z

    and C. Baines. Quantum magnetism in the paratacamite family:14] Stephen Blundell. Magnetism in Condensed Matter. OxfordElectrons and Quantum Magnetism. Graduate Texts in Con-

  1. Magnetic spectroscopy and microscopy of functional materials

    E-Print Network [OSTI]

    Jenkins, C.A.

    2012-01-01T23:59:59.000Z

    transitions for magnetic refrigeration. Appl Phys Lett, 97(these e?ects in magnetic refrigeration and actuation makesheat ?ow with the goal of magnetic refrigeration (adiabatic

  2. Superconducting Magnet Technology for Future Hadron Colliders

    E-Print Network [OSTI]

    Scanlan, R.M.

    2011-01-01T23:59:59.000Z

    I. Superconducting Magnet Technology for Future Hadl"On1994. M.N. Wilson, Superconducting Magnets (Clarendon Press,The application of superconducting magnets to large-scale

  3. Superconducting magnetic coil

    DOE Patents [OSTI]

    Aized, D.; Schwall, R.E.

    1999-06-22T23:59:59.000Z

    A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil. 15 figs.

  4. Superconducting magnetic coil

    DOE Patents [OSTI]

    Aized, Dawood (Marlboro, MA); Schwall, Robert E. (Northborough, MA)

    1999-06-22T23:59:59.000Z

    A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil.

  5. Magnetic fluid flow phenomena in DC and rotating magnetic fields

    E-Print Network [OSTI]

    Rhodes, Scott E. (Scott Edward), 1981-

    2004-01-01T23:59:59.000Z

    An investigation of magnetic fluid experiments and analysis is presented in three parts: a study of magnetic field induced torques in magnetorheological fluids, a characterization and quantitative measurement of properties ...

  6. Magnetic catalysis and inverse magnetic catalysis in QCD

    E-Print Network [OSTI]

    Niklas Mueller; Jan M. Pawlowski

    2015-02-27T23:59:59.000Z

    We investigate the effects of strong magnetic fields on the QCD phase structure at vanishing density by solving the gluon and quark gap equations, and by studying the dynamics of the quark scattering with the four-fermi coupling. The chiral crossover temperature as well as the chiral condensate are computed. For asymptotically large magnetic fields we find magnetic catalysis, while we find inverse magnetic catalysis for intermediate magnetic fields. Moreover, for large magnetic fields the chiral phase transition for massless quarks turns into a crossover. The underlying mechanisms are then investigated analytically within a few simplifications of the full numerical analysis. We find that a combination of gluon screening effects and the weakening of the strong coupling is responsible for the phenomenon of inverse catalysis. In turn, the magnetic catalysis at large magnetic field is already indicated by simple arguments based on dimensionality.

  7. Magnetic nanowire based high resolution magnetic force microscope probes

    E-Print Network [OSTI]

    Qin, Lu-Chang

    -resolution magnetic force microscope probes using preformed magnetic nanowires. Nickel and cobalt nanowires produced by electrodeposition were directly assembled onto the tip of a commercial atomic force microscope cantilever

  8. Magnetic Field Measurement System

    SciTech Connect (OSTI)

    Kulesza, Joe; Johnson, Eric; Lyndaker, Aaron; Deyhim, Alex; Waterman, Dave; Blomqvist, K. Ingvar [Advanced Design Consulting USA, 126 Ridge Road, P.O. Box 187, Lansing, NY 14882 (United States); Dunn, Jonathan Hunter [MAX-lab, SE-221 00 Lund (Sweden)

    2007-01-19T23:59:59.000Z

    A magnetic field measurement system was designed, built and installed at MAX Lab, Sweden for the purpose of characterizing the magnetic field produced by Insertion Devices (see Figure 1). The measurement system consists of a large granite beam roughly 2 feet square and 14 feet long that has been polished beyond laboratory grade for flatness and straightness. The granite precision coupled with the design of the carriage yielded minimum position deviations as measured at the probe tip. The Hall probe data collection and compensation technique allows exceptional resolution and range while taking data on the fly to programmable sample spacing. Additional flip coil provides field integral data.

  9. Cool Magnetic Molecules

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

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

  10. Magnetic nanoworms Systematic Surface Engineering of Magnetic Nanoworms

    E-Print Network [OSTI]

    Bhatia, Sangeeta

    Magnetic nanoworms Systematic Surface Engineering of Magnetic Nanoworms for in vivo Tumor Targeting and Engineering Program Department of Chemistry and Biochemistry University of California, San Diego 9500 Gilman magnetic materials nanoworms peptides tumor targeting 694 ß 2009 Wiley-VCH Verlag GmbH & Co. KGa

  11. Magnetic Coordinates for Systems with Imperfect Magnetic Surfaces

    E-Print Network [OSTI]

    Dewar, Robert L.

    Magnetic Coordinates for Systems with Imperfect Magnetic Surfaces R. L. Dewar and S. R. Hudson & Engineering, The Australian National University, Canberra, A.C.T. 0200, Australia e-mail: robert-orbits, and the surfaces are formed from a continuous one-parameter family of such orbits. Magnetic field-line flow

  12. Magnetic refrigeration apparatus and method

    DOE Patents [OSTI]

    Barclay, John A. (Los Alamos, NM); Overton, Jr., William C. (Los Alamos, NM); Stewart, Walter F. (Los Alamos, NM)

    1984-01-01T23:59:59.000Z

    The disclosure relates to refrigeration through magnetizing and demagnitizing a body by rotating it within a magnetic field. Internal and external heat exchange fluids and in one embodiment, a regenerator, are used.

  13. Large Magnetization at Carbon Surfaces

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

    Large Magnetization at Carbon Surfaces Print From organic matter to pencil lead, carbon is a versatile element. Now, another use has been found: magnets. One would not expect pure...

  14. Optically Enhanced Magnetic Resonance

    E-Print Network [OSTI]

    Suter, Dieter

    , like spatial structures or molecular dynamics. While the direct excitation of nuclear spin transitions.1 Motivation The physical mechanism of nuclear magnetic resonance spectroscopy, the excitation of transitions light for polarizing the spin system or for observing its dynamics. This possibility arises from

  15. Rotary magnetic heat pump

    DOE Patents [OSTI]

    Kirol, Lance D. (Shelly, ID)

    1988-01-01T23:59:59.000Z

    A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation.

  16. Rotary magnetic heat pump

    DOE Patents [OSTI]

    Kirol, L.D.

    1987-02-11T23:59:59.000Z

    A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation. 5 figs.

  17. Magnetic resonance apparatus

    DOE Patents [OSTI]

    Jackson, Jasper A. (Los Alamos, NM); Cooper, Richard K. (Los Alamos, NM)

    1982-01-01T23:59:59.000Z

    Means for producing a region of homogeneous magnetic field remote from the source of the field, wherein two equal field sources are arranged axially so their fields oppose, producing a region near the plane perpendicular to the axis midway between the sources where the radial component of the field goes through a maximum. Near the maximum, the field is homogeneous over prescribed regions.

  18. Magnetic Monopole Searches

    E-Print Network [OSTI]

    G. Giacomelli; L. Patrizii

    2005-06-07T23:59:59.000Z

    In these lecture notes we discuss the status of the searches for classical Dirac Magnetic Monopoles (MMs) at accelerators, for GUT superheavy MMs in the penetrating cosmic radiation and for Intermediate Mass MMs. Also the searches for nuclearites and Q-balls are considered.

  19. Magnetic refrigeration for spacecraft systems

    SciTech Connect (OSTI)

    Barclay, J.A.

    1981-01-01T23:59:59.000Z

    Magnetic refrigerators, i.e., those that use the magnetocaloric effect of a magnetic working material in a thermodynamic cycle, offer potentially reliable, and efficient refrigeration over a variety of temperature ranges and cooling powers. A descriptive analysis of magnetic refrigeration systems is performed with particular emphasis on more efficient infrared detector cooling. Three types of magnetic refrigerator designs are introduced to illustrate some of the possibilities.

  20. Ames Lab 101: Magnetic Refrigeration

    ScienceCinema (OSTI)

    Pecharsky, Vitalij

    2013-03-01T23:59:59.000Z

    Vitalij Pecharsky, distinguished professor of materials science and engineering, discusses his research in magnetic refrigeration at Ames Lab.

  1. Ames Lab 101: Magnetic Refrigeration

    SciTech Connect (OSTI)

    Pecharsky, Vitalij

    2011-01-01T23:59:59.000Z

    Vitalij Pecharsky, distinguished professor of materials science and engineering, discusses his research in magnetic refrigeration at Ames Lab.

  2. Magnetic reconnection in nontoroidal plasmas

    SciTech Connect (OSTI)

    Boozer, Allen H. [Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 (United States)

    2005-07-15T23:59:59.000Z

    Magnetic reconnection is a major issue in solar and astrophysical plasmas. The mathematical result that the evolution of a magnetic field with only point nulls is always locally ideal limits the nature of reconnection in nontoroidal plasmas. Here it is shown that the exponentially increasing separation of neighboring magnetic field lines, which is generic, tends to produce rapid magnetic reconnection if the length of the field lines is greater than about 20 times the exponentiation, or Lyapunov, length.

  3. Future Directions for Magnetic Sensors

    E-Print Network [OSTI]

    and Engineering Laboratory Magnetic tunnel junction (MTJ) sensors are rapidly becoming the technology of choiceFuture Directions for Magnetic Sensors: HYBRIDMATERIALS Our goal is to develop the scientific expertise needed to allow modeling and simulation to become the driving force in improving magnetic sensors

  4. Club! page 16 Using magnets

    E-Print Network [OSTI]

    Weston, Ken

    at the Magnet Lab like? Often, it's about solving problems. That's what engineers Scott Bole and Lee Marks didRobotics Club! page 16 Using magnets to analyze oil page 28 #12;editor's note What's a typical day recently. Their story began when Lee noticed something odd going on during a magnet-building project: When

  5. LABORATORY VI ELECTRICITY FROM MAGNETISM

    E-Print Network [OSTI]

    Minnesota, University of

    LABORATORY VI ELECTRICITY FROM MAGNETISM Lab VI - 1 In the previous problems you explored the magnetic field and its effect on moving charges. You also saw how electric currents could create magnetic can give rise to electric currents. This is the effect that allows the generation of electricity

  6. Enlarge Image Peer pressure. Magnetic

    E-Print Network [OSTI]

    Thywissen, Joseph

    to stick it to your refrigerator, but an ultra-cold gas magnetizes itself just as do metals such as ironEnlarge Image Peer pressure. Magnetic domains in steel (vertical bans) arise when neighboring electrons point their magnetic poles in the same direction. CREDIT: ZUREKS, CHRIS VARDON

  7. Low-temperature magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, J.A.

    1983-05-26T23:59:59.000Z

    The invention relates to magnetic refrigeration and more particularly to low temperature refrigeration between about 4 and about 20 K, with an apparatus and method utilizing a belt of magnetic material passed in and out of a magnetic field with heat exchangers within and outside the field operably disposed to accomplish refrigeration.

  8. Low-temperature magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, John A. (Los Alamos, NM)

    1985-01-01T23:59:59.000Z

    The disclosure is directed to a low temperature 4 to 20 K. refrigeration apparatus and method utilizing a ring of magnetic material moving through a magnetic field. Heat exchange is accomplished in and out of the magnetic field to appropriately utilize the device to execute Carnot and Stirling cycles.

  9. Low field magnetic resonance imaging

    DOE Patents [OSTI]

    Pines, Alexander (Berkeley, CA); Sakellariou, Dimitrios (Billancourt, FR); Meriles, Carlos A. (Fort Lee, NJ); Trabesinger, Andreas H. (London, GB)

    2010-07-13T23:59:59.000Z

    A method and system of magnetic resonance imaging does not need a large homogenous field to truncate a gradient field. Spatial information is encoded into the spin magnetization by allowing the magnetization to evolve in a non-truncated gradient field and inducing a set of 180 degree rotations prior to signal acquisition.

  10. Method of making permanent magnets

    DOE Patents [OSTI]

    McCallum, R.W.; Dennis, K.W.; Lograsso, B.K.; Anderson, I.E.

    1993-09-07T23:59:59.000Z

    A method for making an isotropic permanent magnet comprises atomizing a melt of a rare earth-transition metal alloy (e.g., an Nd--Fe--B alloy enriched in Nd and B) under conditions to produce protectively coated, rapidly solidified, generally spherical alloy particles. Wherein a majority of the particles are produced/size classified within a given size fraction (e.g., 5 to 40 microns diameter) exhibiting optimum as-atomized magnetic properties and subjecting the particles to concurrent elevated temperature and elevated isotropic pressure for a time effective to yield a densified, magnetically isotropic magnet compact having enhanced magnetic properties and mechanical properties. 13 figures.

  11. Magnetic Edge States in Graphene

    E-Print Network [OSTI]

    Gabriela Murguia

    2010-08-29T23:59:59.000Z

    Magnetic confinement in graphene has been of recent and growing interest because its potential applications in nanotechnology. In particular, the observation of the so called magnetic edge states in graphene has opened the possibility to deepen into the generation of spin currents and its applications in spintronics. We study the magnetic edge states of quasi-particles arising in graphene monolayers due to an inhomogeneous magnetic field of a magnetic barrier in the formalism of the two-dimensional massless Dirac equation. We also show how the solutions of such states in each of both triangular sublattices of the graphene are related through a supersymmetric transformation in the quantum mechanical sense.

  12. Fast superconducting magnetic field switch

    DOE Patents [OSTI]

    Goren, Yehuda (Mountain View, CA); Mahale, Narayan K. (The Woodlands, TX)

    1996-01-01T23:59:59.000Z

    The superconducting magnetic switch or fast kicker magnet is employed with electron stream or a bunch of electrons to rapidly change the direction of flow of the electron stream or bunch of electrons. The apparatus employs a beam tube which is coated with a film of superconducting material. The tube is cooled to a temperature below the superconducting transition temperature and is subjected to a constant magnetic field which is produced by an external dc magnet. The magnetic field produced by the dc magnet is less than the critical field for the superconducting material, thus, creating a Meissner Effect condition. A controllable fast electromagnet is used to provide a magnetic field which supplements that of the dc magnet so that when the fast magnet is energized the combined magnetic field is now greater that the critical field and the superconducting material returns to its normal state allowing the magnetic field to penetrate the tube. This produces an internal field which effects the direction of motion and of the electron stream or electron bunch. The switch can also operate as a switching mechanism for charged particles.

  13. Transient magnetic field and temperature modeling in large magnet applications

    SciTech Connect (OSTI)

    Gurol, H.; Hardy, G.E.; Peck, S.D.; Leung, E. (General Dynamics Corp., San Diego, CA (USA). Space Systems Div.)

    1989-07-01T23:59:59.000Z

    This paper discusses a coupled magnetic/thermal model developed to study heat and magnetic field diffusion in conducting materials subject to time-varying external fields. There are numerous applications, both military and commercial. These include: energy storage devices, pulsed power transformers, and electromagnetic launchers. The time scales of interest may range from a magnetic field pulse of a microsecond in an electromagnetic launcher, to hundreds of seconds in an energy storage magnet. The problem can be dominated by either the magnetic field or heat diffusion, depending on the temperature and the material properties of the conductor. In general, heat diffuses much more rapidly in high electrical conductivity materials of cryogenic temperatures. The magnetic field takes longer to diffuse, since screening currents can be rapidly set up which shield the interior of the material from further magnetic field penetration. Conversely, in high resistivity materials, the magnetic field diffuses much more rapidly. A coupled two-dimensional thermal/magnetic model has been developed. The results of this model, showing the time and spatial variation of the magnetic field and temperature, are discussed for the projectile of an electromagnetic launcher.

  14. Magnetic shielding design analysis

    SciTech Connect (OSTI)

    Kerns, J.A.; LaPaz, A.D.; Fabyan, J.

    1983-12-27T23:59:59.000Z

    Two passive magnetic-shielding-design approaches for static external fields are reviewed. The first approach uses the shielding solutions for spheres and cylinders while the second approach requires solving Maxwell's equations. Experimental data taken at LLNL are compared with the results from these shieldings-design methods, and improvements are recommended for the second method. Design considerations are discussed here along with the importance of material gaps in the shield.

  15. High Magnetic Field Multipoles Generated by Superconductor Magnetization within a Set of Nested Superconducting Correction Coils

    E-Print Network [OSTI]

    Green, M.A.

    2011-01-01T23:59:59.000Z

    magnetization of the superconductor in the long correctorsMultipoles Generated by Superconductor Magnetization WithinMULTIPOLES GENERATED BY SUPERCONDUCTOR MAGNETIZATION WITHIN

  16. Continuous magnetic separator and process

    DOE Patents [OSTI]

    Oder, Robin R. (Export, PA); Jamison, Russell E. (Lower Burrell, PA)

    2008-04-22T23:59:59.000Z

    A continuous magnetic separator and process for separating a slurry comprising magnetic particles into a clarified stream and a thickened stream. The separator has a container with a slurry inlet, an overflow outlet for the discharge of the clarified slurry stream, and an underflow outlet for the discharge of a thickened slurry stream. Magnetic particles in the slurry are attracted to, and slide down, magnetic rods within the container. The slurry is thus separated into magnetic concentrate and clarified slurry. Flow control means can be used to control the ratio of the rate of magnetic concentrate to the rate of clarified slurry. Feed control means can be used to control the rate of slurry feed to the slurry inlet.

  17. Thin film superconductor magnetic bearings

    DOE Patents [OSTI]

    Weinberger, Bernard R. (Avon, CT)

    1995-12-26T23:59:59.000Z

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

  18. Magnetic cooling at Risoe DTU

    E-Print Network [OSTI]

    Nielsen, K K; Jensen, J B; Bahl, C R H; Pryds, N; Smith, A; Nordentoft, A; Hattel, J

    2009-01-01T23:59:59.000Z

    Magnetic refrigeration at room temperature is of great interest due to a long-term goal of making refrigeration more energy-efficient, less noisy and free of any environmentally hostile materials. A refrigerator utilizing an active magnetic regenerator (AMR) is based on the magnetocaloric effect, which manifests itself as a temperature change in magnetic materials when subjected to a varying magnetic field. In this work we present the current state of magnetic refrigeration research at Risoe DTU with emphasis on the numerical modeling of an existing AMR test machine. A 2D numerical heat-transfer and fluid-flow model that represents the experimental setup is presented. Experimental data of both no-heat load and heat load situations are compared to the model. Moreover, results from the numerical modeling of the permanent magnet design used in the system are presented.

  19. Journal of Magnetism and Magnetic Materials 281 (2004) 272275 Effects of high magnetic field annealing on texture and

    E-Print Network [OSTI]

    Garmestani, Hamid

    Journal of Magnetism and Magnetic Materials 281 (2004) 272­275 Effects of high magnetic field annealing on texture and magnetic properties of FePd D.S. Lia, *, H. Garmestania , Shi-shen Yanb , M China c National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Drive

  20. Journal of Magnetism and Magnetic Materials 286 (2005) 324328 Light-free magnetic resonance force microscopy for studies of

    E-Print Network [OSTI]

    Journal of Magnetism and Magnetic Materials 286 (2005) 324­328 Light-free magnetic resonance force for Physical Sciences, College Park, MD, USA Available online 4 November 2004 Abstract Magnetic resonance force microscopy is a scanned probe technique capable of three-dimensional magnetic resonance imaging. Its

  1. Tests of prototype SSC magnets

    SciTech Connect (OSTI)

    Strait, J.

    1987-04-24T23:59:59.000Z

    Results are presented from tests of the first two full length prototype SSC dipole magnets. Magnetic field measurements have been made at currents up to 2000 A. The two magnets achieved peak currents at 4.5K of 5790 A and 6450 A, respectively, substantially below the short sample limit of 6700 A. These peak values, however, could not be achieved reproducibly. Data are presented from studies performed to try to understand the poor quench performance.

  2. Metallic Magnetic Hetrostructures

    E-Print Network [OSTI]

    Leung, Chi Wah

    cross-over and exchange bias in Co/FeMn/CuNi trilayers’, M.G. Blamire, M. Ali, C.W. Leung, C.H. Marrows and B.J. Hickey, Phys. Rev. Lett., (submitted). iii Presentations - Joint Magnetics Workshop 01 (University of Cardiff, Cardiff, 2001) ‘Study... , in no particular order: Zoe Barber, Ashish Grag, Karen Yates, Neil Mathur, Bas van Aken, Brian Pang, Moon-Ho Jo, James Chapman, Mary Vickers, Neil Todd, Jerome Wolfman, Pak Kin Wong and Robert Hadfield. During the course of the project I have spent two weeks...

  3. Try This: Household Magnets

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening a solidSynthesisAppliancesTrending:Schedule FYHousehold Magnets

  4. Recycling Magnets | Jefferson Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection RadiationRecord-Setting MicroscopyJuneRecycling Magnets July 15, 2013

  5. Measurements of magnetic field alignment

    SciTech Connect (OSTI)

    Kuchnir, M.; Schmidt, E.E.

    1987-11-06T23:59:59.000Z

    The procedure for installing Superconducting Super Collider (SSC) dipoles in their respective cryostats involves aligning the average direction of their field with the vertical to an accuracy of 0.5 mrad. The equipment developed for carrying on these measurements is described and the measurements performed on the first few prototypes SSC magnets are presented. The field angle as a function of position in these 16.6 m long magnets is a characteristic of the individual magnet with possible feedback information to its manufacturing procedure. A comparison of this vertical alignment characteristic with a magnetic field intensity (by NMR) characteristic for one of the prototypes is also presented. 5 refs., 7 figs.

  6. BNL Direct Wind Superconducting Magnets

    SciTech Connect (OSTI)

    Parker, B.; Anerella, M.; Escallier, J.; Ghosh, A.; Jain, A.; Marone, A.; Muratore, A.; Wanderer, P.

    2011-09-12T23:59:59.000Z

    BNL developed Direct Wind magnet technology is used to create a variety of complex multi-functional multi-layer superconducting coil structures without the need for creating custom production tooling and fixturing for each new project. Our Direct Wind process naturally integrates prestress into the coil structure so external coil collars and yokes are not needed; the final coil package transverse size can then be very compact. Direct Wind magnets are produced with very good field quality via corrections applied during the course of coil winding. The HERA-II and BEPC-II Interaction Region (IR) magnet, J-PARC corrector and Alpha antihydrogen magnetic trap magnets and our BTeV corrector magnet design are discussed here along with a full length ILC IR prototype magnet presently in production and the coils that were wound for an ATF2 upgrade at KEK. A new IR septum magnet design concept for a 6.2 T combined-function IR magnet for eRHIC, a future RHIC upgrade, is introduced here.

  7. $?^{-}$, $?^{* -}$, $?^{* -}$ and $?^{-}$ decuplet baryon magnetic moments

    E-Print Network [OSTI]

    Milton Dean Slaughter

    2011-04-04T23:59:59.000Z

    The properties of the ground state $U$-Spin $={3/2}$ baryon decuplet magnetic moments $\\Delta^{-}$, $\\Xi^{* -}$, $\\Sigma^{* -}$ and $\\Omega^{-}$ and their ground state spin 1/2 cousins $p$, $n$, $\\Lambda$, $\\Sigma^{+}$, $\\Sigma^{0}$, $\\Sigma^{-}$, $\\Xi^{+}$, and $\\Xi^{-}$ have been studied for many years with a modicum of success. The magnetic moments of many are yet to be determined. Of the decuplet baryons, only the magnetic moment of the $\\Omega^{-}$ has been accurately determined. We calculate the magnetic moments of the \\emph{physical} decuplet $U$-Spin $={3/2}$ quartet members without ascribing any specific form to their quark structure or intra-quark interactions.

  8. Magnetic Refrigeration | GE Global Research

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

    temperature," said Frank Johnson, a materials scientist and project leader on GE's magnetic refrigeration project. Developed over the past decade, these new magnetocaloric...

  9. Lensless Imaging of Magnetic Nanostructures

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

    this technique has been especially popular in imaging such complex structures as aerogels and yeast cells. When applying the CDI technique to a magnetic system, the same...

  10. Continuous k-Means Monitoring over Moving Objects

    E-Print Network [OSTI]

    Papadias, Dimitris

    Continuous k-Means Monitoring over Moving Objects Zhenjie Zhang, Yin Yang, Anthony K.H. Tung, and Dimitris Papadias Abstract-- Given a dataset P, a k-means query returns k points in space (called centers study continuous k-means computation at a server that monitors a set of moving objects. Re-evaluating k-means

  11. ORIGINAL PAPER Tribute to Dick Post on His 90th Birthday

    E-Print Network [OSTI]

    that I learned about Dick's interest in electric cars. He and his son Steve published this in Sci-invented the Yin Yang in the first place. Dick also invented Direct Conversion, to make electricity by fusion at very high speed, and a specially-designed electric motor that could deliver 100 horsepower in a device

  12. Size and polydispersity effect on the magnetization of densely packed magnetic nanoparticles.

    E-Print Network [OSTI]

    Boyer, Edmond

    Size and polydispersity effect on the magnetization of densely packed magnetic nanoparticles Paris 13, 93017 Bobigny, France. The magnetic properties of densely packed magnetic nanoparticles (MNP) assemblies are investi- gated from Monte Carlo simulations. The case of iron oxide nanoparticles

  13. Electric-Field Control of Magnetism Intrinsic magnetoelectric coupling describes the microscopic interaction between magnetic and

    E-Print Network [OSTI]

    Maroncelli, Mark

    Electric-Field Control of Magnetism Intrinsic magnetoelectric coupling describes the microscopic interaction between magnetic and electric polarization in a single-phase material. The control of the magnetic of the two interactions. Moderate biaxial compression precipitates local magnetic competition

  14. Global Electrical Conductivity Magnetic Satellite Induction Studies

    E-Print Network [OSTI]

    Constable, Steve

    · Geomagnetic depth sounding (GDS) method Measure horizontal and vertical magnetic fields 2nd-varying magnetic field induces electric currents in conductors. × E = - B t Secondary magnetic fields created by these currents appose the primary magnetic field. So, conductors attenuate magnetic fields. 2nd

  15. Background Material Important Questions about Magnetism

    E-Print Network [OSTI]

    Mojzsis, Stephen J.

    Background Material Important Questions about Magnetism: 1) What is Magnetism?Magnetism is a force or repulsion due to charge is called the electric force. But what about magnetism, is there a fundamental property of some matter that makes things magnetic? The answer is: "sort of." Electric current

  16. Nanolithographically defined magnetic structures and quantum magnetic disk (invited)

    E-Print Network [OSTI]

    - creasing demands for magnetic storage devices with higher density, faster speed, lower power consumption, smaller size, and lower weight than the current state-of-the-art devices. Presently, most magnetic storage. Chou, Peter R. Krauss, and Linshu Kong NanoStructure Laboratory, Department of Electrical Engineering

  17. Magnetic Patterning of Permanent-Magnet Rotors for Microscale Motor/Generators

    E-Print Network [OSTI]

    Magnetic Patterning of Permanent-Magnet Rotors for Microscale Motor/Generators I. Zana* , F, USA Abstract We present and characterize a process to pattern magnetic poles on small permanent-magnet, this approach uses a ferromagnetic magnetizing head (MH) and an externally applied magnetic field, and it offers

  18. SOLAR MAGNETIC TRACKING. IV. THE DEATH OF MAGNETIC FEATURES

    SciTech Connect (OSTI)

    Lamb, D. A.; Howard, T. A.; DeForest, C. E. [Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80302 (United States); Parnell, C. E. [School of Mathematics and Statistics, University of St. Andrews, St. Andrews, KY16 9SS (United Kingdom); Welsch, B. T., E-mail: derek@boulder.swri.edu [Space Sciences Laboratory, University of California-Berkeley, 7 Gauss Way, Berkeley, CA 94720 (United States)

    2013-09-10T23:59:59.000Z

    The removal of magnetic flux from the quiet-Sun photosphere is important for maintaining the statistical steady state of the magnetic field there, for determining the magnetic flux budget of the Sun, and for estimating the rate of energy injected into the upper solar atmosphere. Magnetic feature death is a measurable proxy for the removal of detectable flux, either by cancellation (submerging or rising loops, or reconnection in the photosphere) or by dispersal of flux. We used the SWAMIS feature tracking code to understand how nearly 2 Multiplication-Sign 10{sup 4} magnetic features die in an hour-long sequence of Hinode/SOT/NFI magnetograms of a region of the quiet Sun. Of the feature deaths that remove visible magnetic flux from the photosphere, the vast majority do so by a process that merely disperses the previously detected flux so that it is too small and too weak to be detected, rather than completely eliminating it. The behavior of the ensemble average of these dispersals is not consistent with a model of simple planar diffusion, suggesting that the dispersal is constrained by the evolving photospheric velocity field. We introduce the concept of the partial lifetime of magnetic features, and show that the partial lifetime due to Cancellation of magnetic flux, 22 hr, is three times slower than previous measurements of the flux turnover time. This indicates that prior feature-based estimates of the flux replacement time may be too short, in contrast with the tendency for this quantity to decrease as resolution and instrumentation have improved. This suggests that dispersal of flux to smaller scales is more important for the replacement of magnetic fields in the quiet Sun than observed bipolar cancellation. We conclude that processes on spatial scales smaller than those visible to Hinode dominate the processes of flux emergence and cancellation, and therefore also the quantity of magnetic flux that threads the photosphere.

  19. LABORATORY VI ELECTRICITY FROM MAGNETISM

    E-Print Network [OSTI]

    Minnesota, University of

    LABORATORY VI ELECTRICITY FROM MAGNETISM Lab VI - 1 In the previous problems you explored by electric currents. This lab will carry that investigation one step further, determining how changing magnetic fields can give rise to electric currents. This is the effect that allows the generation

  20. Magnetic bags in hyperbolic space

    E-Print Network [OSTI]

    Stefano Bolognesi; Derek Harland; Paul Sutcliffe

    2015-04-07T23:59:59.000Z

    A magnetic bag is an abelian approximation to a large number of coincident SU(2) BPS monopoles. In this paper we consider magnetic bags in hyperbolic space and derive their Nahm transform from the large charge limit of the discrete Nahm equation for hyperbolic monopoles. An advantage of studying magnetic bags in hyperbolic space, rather than Euclidean space, is that a range of exact charge N hyperbolic monopoles can be constructed, for arbitrarily large values of N, and compared with the magnetic bag approximation. We show that a particular magnetic bag (the magnetic disc) provides a good description of the axially symmetric N-monopole. However, an abelian magnetic bag is not a good approximation to a roughly spherical N-monopole that has more than N zeros of the Higgs field. We introduce an extension of the magnetic bag that does provide a good approximation to such monopoles and involves a spherical non-abelian interior for the bag, in addition to the conventional abelian exterior.

  1. Magnetic-field-dosimetry system

    DOE Patents [OSTI]

    Lemon, D.K.; Skorpik, J.R.; Eick, J.L.

    1981-01-21T23:59:59.000Z

    A device is provided for measuring the magnetic field dose and peak field exposure. The device includes three Hall-effect sensors all perpendicular to each other, sensing the three dimensional magnetic field and associated electronics for data storage, calculating, retrieving and display.

  2. Enlarge Image Peer pressure. Magnetic

    E-Print Network [OSTI]

    Enlarge Image Peer pressure. Magnetic domains in steel (vertical bans) arise when neighboring electrons point their magnetic poles in the same direction. CREDIT: ZUREKS, CHRIS VARDON/WIKIMEDIA By Adrian Cho ScienceNOW Daily News 18 September 2009 It would be tough to stick it to your refrigerator

  3. Exergy analysis of magnetic refrigeration

    E-Print Network [OSTI]

    Lucia, Umberto

    2010-01-01T23:59:59.000Z

    One of the main challenges of the industry today is to face its impact on global warming considering that the greenhouse effect problem is not be solved completely yet. Magnetic refrigeration represents an environment-safe refrigeration technology. The magnetic refrigeration is analysed using the second law analysis and introducing exergy in order to obtain a model for engineering application.

  4. Magnetic bags in hyperbolic space

    E-Print Network [OSTI]

    Bolognesi, Stefano; Sutcliffe, Paul

    2015-01-01T23:59:59.000Z

    A magnetic bag is an abelian approximation to a large number of coincident SU(2) BPS monopoles. In this paper we consider magnetic bags in hyperbolic space and derive their Nahm transform from the large charge limit of the discrete Nahm equation for hyperbolic monopoles. An advantage of studying magnetic bags in hyperbolic space, rather than Euclidean space, is that a range of exact charge N hyperbolic monopoles can be constructed, for arbitrarily large values of N, and compared with the magnetic bag approximation. We show that a particular magnetic bag (the magnetic disc) provides a good description of the axially symmetric N-monopole. However, an abelian magnetic bag is not a good approximation to a roughly spherical N-monopole that has more than N zeros of the Higgs field. We introduce an extension of the magnetic bag that does provide a good approximation to such monopoles and involves a spherical non-abelian interior for the bag, in addition to the conventional abelian exterior.

  5. Superconductivity and Magnetism: Materials Properties

    E-Print Network [OSTI]

    .g. within high-Tc superconductivity, magnetic superconductors, MgB2, CMR materials, nanomagnetism and spin#12;#12;Superconductivity and Magnetism: Materials Properties and Developments #12;Copyright 2003 Risø National Laboratory Roskilde, Denmark ISBN 87-550-3244-3 ISSN 0907-0079 #12;Superconductivity

  6. Magnetic Resonance Facility (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-03-01T23:59:59.000Z

    This fact sheet provides information about Magnetic Resonance Facility capabilities and applications at NREL's National Bioenergy Center. Liquid and solid-state analysis capability for a variety of biomass, photovoltaic, and materials characterization applications across NREL. NREL scientists analyze solid and liquid samples on three nuclear magnetic resonance (NMR) spectrometers as well as an electron paramagnetic resonance (EPR) spectrometer.

  7. NANOSCALE STRUCTURALAND MAGNETIC CHARACTERIZATION USING

    E-Print Network [OSTI]

    Dunin-Borkowski, Rafal E.

    of novel nanoscale storage devices and sensors. However, for successful utilization, it is essential]. Such unique properties of magnetic thin films and nanostructures hold great promise for the development to the characterization of nanostructured magnetic materials. 2. ELECTRON MICROSCOPY METHODS In the transmission electron

  8. Plated lamination structures for integrated magnetic devices

    SciTech Connect (OSTI)

    Webb, Bucknell C.

    2014-06-17T23:59:59.000Z

    Semiconductor integrated magnetic devices such as inductors, transformers, etc., having laminated magnetic-insulator stack structures are provided, wherein the laminated magnetic-insulator stack structures are formed using electroplating techniques. For example, an integrated laminated magnetic device includes a multilayer stack structure having alternating magnetic and insulating layers formed on a substrate, wherein each magnetic layer in the multilayer stack structure is separated from another magnetic layer in the multilayer stack structure by an insulating layer, and a local shorting structure to electrically connect each magnetic layer in the multilayer stack structure to an underlying magnetic layer in the multilayer stack structure to facilitate electroplating of the magnetic layers using an underlying conductive layer (magnetic or seed layer) in the stack as an electrical cathode/anode for each electroplated magnetic layer in the stack structure.

  9. Permanent-magnet multipole with adjustable strength

    DOE Patents [OSTI]

    Halbach, K.

    1982-09-20T23:59:59.000Z

    Two or more magnetically soft pole pieces are symmetrically positioned along a longitudinal axis to provide a magnetic field within a space defined by the pole pieces. Two or more permanent magnets are mounted to an external magnetically-soft cylindrical sleeve which rotates to bring the permanent magnets into closer coupling with the pole pieces and thereby adjustably control the field strength of the magnetic field produced in the space defined by the pole pieces. The permanent magnets are preferably formed of rare earth cobalt (REC) material which has a high remanent magnetic field and a strong coercive force. The pole pieces and the permanent magnets have corresponding cylindrical surfaces which are positionable with respect to each other to vary the coupling there between. Auxiliary permanent magnets are provided between the pole pieces to provide additional magnetic flux to the magnetic field without saturating the pole pieces.

  10. Permanent magnet multipole with adjustable strength

    DOE Patents [OSTI]

    Halbach, Klaus (Berkeley, CA)

    1985-01-01T23:59:59.000Z

    Two or more magnetically soft pole pieces are symmetrically positioned along a longitudinal axis to provide a magnetic field within a space defined by the pole pieces. Two or more permanent magnets are mounted to an external magnetically-soft cylindrical sleeve which rotates to bring the permanent magnets into closer coupling with the pole pieces and thereby adjustably control the field strength of the magnetic field produced in the space defined by the pole pieces. The permanent magnets are preferably formed of rare earth cobalt (REC) material which has a high remanent magnetic field and a strong coercive force. The pole pieces and the permanent magnets have corresponding cylindrical surfaces which are positionable with respect to each other to vary the coupling therebetween. Auxiliary permanent magnets are provided between the pole pieces to provide additional magnetic flux to the magnetic field without saturating the pole pieces.

  11. Purification of recombinant proteins with magnetic nanoclusters

    E-Print Network [OSTI]

    Ditsch, Andre (Andre Paul)

    2005-01-01T23:59:59.000Z

    This thesis focused on the development and analysis of a new class of magnetic fluids for recovery of recombinant proteins from fermentation broth. Magnetic fluids are colloidally stable dispersions of magnetic nanoclusters ...

  12. A direct search for Dirac magnetic monopoles

    E-Print Network [OSTI]

    Mulhearn, Michael James

    2005-01-01T23:59:59.000Z

    Magnetic monopoles are highly ionizing and curve in the direction of the magnetic field. A new dedicated magnetic monopole trigger at CDF, which requires large light pulses in the scintillators of the time-of-flight system, ...

  13. Magnetic nanostructures patterned by block copolymer lithography

    E-Print Network [OSTI]

    Ilievski, Filip, 1980-

    2008-01-01T23:59:59.000Z

    The aim of this research was twofold: understanding the methods of patterning magnetic films using self-assembled block copolymer masks and examining the magnetic reversal mechanisms of as deposited and patterned magnetic ...

  14. Exposure guidelines for magnetic fields

    SciTech Connect (OSTI)

    Miller, G.

    1987-12-01T23:59:59.000Z

    The powerful magnetic fields produced by a controlled fusion experiment at Lawrence Livermore National Laboratory (LLNL) necessitated the development of personnel-exposure guidelines for steady magnetic fields. A literature search and conversations with active researchers showed that it is currently possible to develop preliminary exposure guidelines for steady magnetic fields. An overview of the results of past research into the bioeffects of magnetic fields was compiled, along with a discussion of hazards that may be encountered by people with sickle-cell anemia or medical electronic and prosthetic implants. The LLNL steady magnetic-field exposure guidelines along with a review of developments concerning the safety of time-varying fields were also presented in this compilation. Guidelines developed elsewhere for time varying fields were also given. Further research is needed to develop exposure standards for both steady or time-varying fields.

  15. Superconducting magnetic energy storage

    SciTech Connect (OSTI)

    Hassenzahl, W.

    1988-08-01T23:59:59.000Z

    Recent programmatic developments in Superconducting Magnetic Energy Storage (SMES) have prompted renewed and widespread interest in this field. In mid 1987 the Defense Nuclear Agency, acting for the Strategic Defense Initiative Office, issued a request for proposals for the design and construction of SMES Engineering Test Model (ETM). Two teams, one led by Bechtel and the other by Ebasco, are now engaged in the first phase of the development of a 10 to 20 MWhr ETM. This report presents the rationale for energy storage on utility systems, describes the general technology of SMES, and explains the chronological development of the technology. The present ETM program is outlined; details of the two projects for ETM development are described in other papers in these proceedings. The impact of high T/sub c/ materials on SMES is discussed. 69 refs., 3 figs., 3 tabs.

  16. Permanent Magnet Development for Automotive Traction Motors

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

    Permanent Magnet Development for Automotive Traction Motors Includes: Beyond Rare Earth Magnets (BREM) Iver E. Anderson Ames Laboratory (USDOE) Email: andersoni@ameslab.gov Phone:...

  17. Magnetism in metal-organic capsules

    E-Print Network [OSTI]

    Atwood, Jerry L.

    2010-01-01T23:59:59.000Z

    Quantum Spin Chains in Magnetism: Molecules to Materials, J.Magnetism in metal-organic capsules Jerry L. Atwood,* a Euan

  18. A Brief Note on Jupiter's Magnetism

    E-Print Network [OSTI]

    B. G. Sidharth

    1999-05-06T23:59:59.000Z

    A recent model which gives the contribution of the earth's solid core to geo magnetism is seen to explain Jupiter's magnetism also.

  19. Magnetic Nanocrystalline Films Softened by Obliquely Accelerating...

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

    morphology and thereby ability to custom tailor magnetic characteristics. Citation: Meyer DR, M Faheem, M Campanell, J Antony, AM Sharma, and Y Qiang.2007."Magnetic...

  20. Magnetic filtration process, magnetic filtering material, and methods of forming magnetic filtering material

    DOE Patents [OSTI]

    Taboada-Serrano, Patricia; Tsouris, Constantino; Contescu, Cristian I; McFarlane, Joanna

    2013-10-08T23:59:59.000Z

    The present invention provides magnetically responsive activated carbon, and a method of forming magnetically responsive activated carbon. The method of forming magnetically responsive activated carbon typically includes providing activated carbon in a solution containing ions of ferrite forming elements, wherein at least one of the ferrite forming elements has an oxidation state of +3 and at least a second of the ferrite forming elements has an oxidation state of +2, and increasing pH of the solution to precipitate particles of ferrite that bond to the activated carbon, wherein the activated carbon having the ferrite particles bonded thereto have a positive magnetic susceptibility. The present invention also provides a method of filtering waste water using magnetic activated carbon.

  1. Ch 20. Magnetism Liu UCD Phy1B 2012 1

    E-Print Network [OSTI]

    Yoo, S. J. Ben

    Ch 20. Magnetism Liu UCD Phy1B 2012 1 #12;I. MagnetI. Magnet Poles of a magnet: magnetic effect is strongest When the magnet is freely suspended North pole: pointing to north South pole: pointing to south Poles always come in pairs Liu UCD Phy1B 2012 2 #12;Magnetic MaterialsMagnetic Materials Magnetite Fe3O4

  2. Magnetic dipole discharges. III. Instabilities

    SciTech Connect (OSTI)

    Stenzel, R. L.; Urrutia, J. M. [Department of Physics and Astronomy, University of California Los Angeles, California 90095-1547 (United States)] [Department of Physics and Astronomy, University of California Los Angeles, California 90095-1547 (United States); Ionita, C.; Schrittwieser, R. [Institute for Ion Physics and Applied Physics, University of Innsbruck A-6020 Innsbruck (Austria)] [Institute for Ion Physics and Applied Physics, University of Innsbruck A-6020 Innsbruck (Austria)

    2013-08-15T23:59:59.000Z

    Instabilities in a cross-field discharge around a permanent magnet have been investigated. The permanent magnet serves as a cold cathode and the chamber wall as an anode. The magnet is biased strongly negative and emits secondary electrons due to impact of energetic ions. The electrons outside the sheath are confined by the strong dipolar magnetic field and by the ion-rich sheath surrounding the magnet. The electron energy peaks in the equatorial plane where most ionization occurs and the ions are trapped in a negative potential well. The discharge mechanism is the same as that of cylindrical and planar magnetrons, but here extended to a 3-D cathode geometry using a single dipole magnet. While the basic properties of the discharge are presented in a companion paper, the present focus is on various observed instabilities. The first is an ion sheath instability which oscillates the plasma potential outside the sheath below the ion plasma frequency. It arises in ion-rich sheaths with low electron supply, which is the case for low secondary emission yields. Sheath oscillations modulate the discharge current creating oscillating magnetic fields. The second instability is current-driven ion sound turbulence due to counter-streaming electrons and ions. The fluctuations have a broad spectrum and short correlation lengths in all directions. The third type of fluctuations is spiky potential and current oscillations in high density discharges. These appear to be due to unstable emission properties of the magnetron cathode.

  3. Magnetically driven quantum heat engine

    E-Print Network [OSTI]

    Enrique Muñoz; Francisco J. Peña

    2014-05-12T23:59:59.000Z

    We studied the efficiency of two different schemes for a magnetically driven quantum heat engine, by considering as the working substance a single nonrelativistic particle trapped in a cylindrical potential well, in the presence of an external magnetic field. The first scheme is a cycle, composed of two adiabatic and two isoenergetic reversible trajectories in configuration space. The trajectories are driven by a quasistatic modulation of the external magnetic-field intensity. The second scheme is a variant of the former, where the isoenergetic trajectories are replaced by isothermal ones, along which the system is in contact with macroscopic thermostats. This second scheme constitutes a quantum analog of the classical Carnot cycle.

  4. Magnetic cellulose-derivative structures

    DOE Patents [OSTI]

    Walsh, Myles A. (Falmouth, MA); Morris, Robert S. (Fairhaven, MA)

    1986-09-16T23:59:59.000Z

    Structures to serve as selective magnetic sorbents are formed by dissolving a cellulose derivative such as cellulose triacetate in a solvent containing magnetic particles. The resulting solution is sprayed as a fine mist into a chamber containing a liquid coagulant such as n-hexane in which the cellulose derivative is insoluble but in which the coagulant is soluble or miscible. On contact with the coagulant, the mist forms free-flowing porous magnetic microspheric structures. These structures act as containers for the ion-selective or organic-selective sorption agent of choice. Some sorbtion agents can be incorporated during the manufacture of the structure.

  5. The Magnetism of Neutron States

    E-Print Network [OSTI]

    B. G. Sidharth

    2003-10-01T23:59:59.000Z

    The recent measurement by Bignami and co-workers of the magnetic field of a neutron star for the first time gives a value that differs by about two orders of magnitude from the expected value. The speculation has been that the nuclear matter in the neutron stars exhibits some exotic behaviour. In this note we argue that this exotic behaviour is an anomalous statistics obeyed by the neutrons, and moreover these considerations lead to a value of the magnetic field that agrees with the observation. The same considerations also correctly give the magnetic fields of the earth and Jupiter.

  6. Magnetic moment versus tensor charge

    E-Print Network [OSTI]

    M. Mekhfi

    2005-05-10T23:59:59.000Z

    We express the baryon magnetic moments in terms of the baryon tensor charges, considering the quarks as relativistic interacting objects. Once tensor charges get measured accurately, the formula for the baryon magnetic moment will serve to extract precise information on the quark anomalous magnetic moment, the quark effective mass and the ratio of the quark constituent mass to the quark effective mass. The analogous formula for the baryon electric dipole moment is of no great use as it gets eventually sizable contributions from various CP- violating sources not necessary associated to the quark electric dipole moment.

  7. Nuclear magnetic resonance contrast agents

    DOE Patents [OSTI]

    Smith, P.H.; Brainard, J.R.; Jarvinen, G.D.; Ryan, R.R.

    1997-12-30T23:59:59.000Z

    A family of contrast agents for use in magnetic resonance imaging and a method of enhancing the contrast of magnetic resonance images of an object by incorporating a contrast agent of this invention into the object prior to forming the images or during formation of the images. A contrast agent of this invention is a paramagnetic lanthanide hexaazamacrocyclic molecule, where a basic example has the formula LnC{sub 16}H{sub 14}N{sub 6}. Important applications of the invention are in medical diagnosis, treatment, and research, where images of portions of a human body are formed by means of magnetic resonance techniques. 10 figs.

  8. Magnetic nanoparticles for applications in oscillating magnetic field

    SciTech Connect (OSTI)

    Peeraphatdit, Chorthip

    2010-12-15T23:59:59.000Z

    Enzymatic and thermochemical catalysis are both important industrial processes. However, the thermal requirements for each process often render them mutually exclusive: thermochemical catalysis requires high temperature that denatures enzymes. One of the long-term goals of this project is to design a thermocatalytic system that could be used with enzymatic systems in situ to catalyze reaction sequences in one pot; this system would be useful for numerous applications e.g. conversion of biomass to biofuel and other commodity products. The desired thermocatalytic system would need to supply enough thermal energy to catalyze thermochemical reactions, while keeping the enzymes from high temperature denaturation. Magnetic nanoparticles are known to generate heat in an oscillating magnetic field through mechanisms including hysteresis and relaxational losses. We envisioned using these magnetic nanoparticles as the local heat source embedded in sub-micron size mesoporous support to spatially separate the particles from the enzymes. In this study, we set out to find the magnetic materials and instrumental conditions that are sufficient for this purpose. Magnetite was chosen as the first model magnetic material in this study because of its high magnetization values, synthetic control over particle size, shape, functionalization and proven biocompatibility. Our experimental designs were guided by a series of theoretical calculations, which provided clues to the effects of particle size, size distribution, magnetic field, frequency and reaction medium. Materials of theoretically optimal size were synthesized, functionalized, and their effects in the oscillating magnetic field were subsequently investigated. Under our conditions, the materials that clustered e.g. silica-coated and PNIPAM-coated iron oxides exhibited the highest heat generation, while iron oxides embedded in MSNs and mesoporous iron oxides exhibited the least bulk heating. It is worth noting that the specific loss power of PNIPAM-coated Fe{sub 3}O{sub 4} was peculiarly high, and the heat loss mechanism of this material remains to be elucidated. Since thermocatalysis is a long-term goal of this project, we also investigated the effects of the oscillating magnetic field system for the synthesis of 7-hydroxycoumarin-3-carboxylic acid. Application of an oscillating magnetic field in the presence of magnetic particles with high thermal response was found to effectively increase the reaction rate of the uncatalyzed synthesis of the coumarin derivative compared to the room temperature control.

  9. Magnetic Microscopy and Imaging II John Chapman, Chairman Study of in-plane magnetic domains with magnetic transmission

    E-Print Network [OSTI]

    Bayreuther, Günther

    with magnetic transmission x-ray microscopy P. Fischer,a) T. Eimu¨ller, and G. Schu¨tz University of Wu be designed by en- gaging, e.g., the different magnetic couplings between each layers. Due to a balanceMagnetic Microscopy and Imaging II John Chapman, Chairman Study of in-plane magnetic domains

  10. Improved superconducting magnet wire

    DOE Patents [OSTI]

    Schuller, I.K.; Ketterson, J.B.

    1983-08-16T23:59:59.000Z

    This invention is directed to a superconducting tape or wire composed of alternating layers of copper and a niobium-containing superconductor such as niobium of NbTi, Nb/sub 3/Sn or Nb/sub 3/Ge. In general, each layer of the niobium-containing superconductor has a thickness in the range of about 0.05 to 1.5 times its coherence length (which for Nb/sub 3/Si is 41 A) with each copper layer having a thickness in the range of about 170 to 600 A. With the use of very thin layers of the niobium composition having a thickness within the desired range, the critical field (H/sub c/) may be increased by factors of 2 to 4. Also, the thin layers of the superconductor permit the resulting tape or wire to exhibit suitable ductility for winding on a magnet core. These compositions are also characterized by relatively high values of critical temperature and therefore will exhibit a combination of useful properties as superconductors.

  11. Magnet Girder Assembly and Installation

    SciTech Connect (OSTI)

    None

    2012-12-12T23:59:59.000Z

    It takes teamwork to assemble and install magnet girders for the storage ring of the National Synchrotron Light Source II. NSLS-II is now under construction at Brookhaven Lab.

  12. Magnet Girder Assembly and Installation

    ScienceCinema (OSTI)

    None

    2013-07-17T23:59:59.000Z

    It takes teamwork to assemble and install magnet girders for the storage ring of the National Synchrotron Light Source II. NSLS-II is now under construction at Brookhaven Lab.

  13. Magnetically stimulated fluid flow patterns

    ScienceCinema (OSTI)

    Martin, Jim; Solis, Kyle

    2014-08-06T23:59:59.000Z

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  14. Magnetically stimulated fluid flow patterns

    SciTech Connect (OSTI)

    Martin, Jim; Solis, Kyle

    2014-03-06T23:59:59.000Z

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  15. Superconducting Magnets for Particle Accelerators

    E-Print Network [OSTI]

    Rossi, L

    2012-01-01T23:59:59.000Z

    Superconductivity has been the most influential technology in the field of accelerators in the last 30 years. Since the commissioning of the Tevatron, which demonstrated the use and operability of superconductivity on a large scale, superconducting magnets and rf cavities have been at the heart of all new large accelerators. Superconducting magnets have been the invariable choice for large colliders, as well as cyclotrons and large synchrotrons. In spite of the long history of success, superconductivity remains a difficult technology, requires adequate R&D and suitable preparation, and has a relatively high cost. Hence, it is not surprising that the development has also been marked by a few setbacks. This article is a review of the main superconducting accelerator magnet projects; it highlights the main characteristics and main achievements, and gives a perspective on the development of superconducting magnets for the future generation of very high energy colliders.

  16. Magnetically insulated transmission line oscillator

    DOE Patents [OSTI]

    Bacon, Larry D. (Albuquerque, NM); Ballard, William P. (Albuquerque, NM); Clark, M. Collins (Albuquerque, NM); Marder, Barry M. (Albuquerque, NM)

    1988-01-01T23:59:59.000Z

    A magnetically insulated transmission line oscillator employs self-generated magnetic fields to generate microwave energy. An anode of the oscillator includes slow-wave structures which are formed of a plurality of thin conductive vanes defining cavities therebetween, and a gap is formed between the anode and a cathode of the oscillator. In response to a pulsed voltage applied to the anode and cathode, self-generated magnetic fields arfe produced in a cross-field orientation with respect to the orientation of the electric field between the anode and the cathode. The cross-field magnetic fields insulate the flow of electrons in the gap and confine the flow of electrons within the gap.

  17. Are Cluster Magnetic Fields Primordial ?

    E-Print Network [OSTI]

    Robi Banerjee; Karsten Jedamzik

    2004-09-07T23:59:59.000Z

    We present results of a detailed and fully non-linear numerical and analytical investigation of magnetic field evolution from the very earliest cosmic epochs to the present. We find that, under reasonable assumptions concerning the efficiency of a putative magnetogenesis era during cosmic phase transitions, surprisingly strong magnetic fields 10^{-13} - 10^{-11} Gauss, on comparatively small scales 100 pc - 10 kpc may survive to the present. Building on prior work on the evolution of magnetic fields during the course of gravitational collapse of a cluster, which indicates that pre-collapse fields of 4\\times 10^{-12} Gauss extant on small scales may suffice to produce clusters with acceptable Faraday rotation measures, we question the widely hold view that cluster magnetic fields may not be entirely of primordial origin.

  18. The Plasma Magnet John Slough

    E-Print Network [OSTI]

    Shepherd, Simon

    windmill) Two polyphase magnetic coils (stator) are used to drive steady ring currents in the local plasma representation in the ring currents formed when the magnetosphere is compressed by the solar wind. The process

  19. Maxwell's fluid model of magnetism

    E-Print Network [OSTI]

    Robert Brady; Ross Anderson

    2015-02-20T23:59:59.000Z

    In 1861, Maxwell derived two of his equations of electromagnetism by modelling a magnetic line of force as a `molecular vortex' in a fluid-like medium. Later, in 1980, Berry and colleagues conducted experiments on a `phase vortex', a wave geometry in a fluid which is analogous to a magnetic line of force and also exhibits behaviour corresponding to the quantisation of magnetic flux. Here we unify these approaches by writing down a solution to the equations of motion for a compressible fluid which behaves in the same way as a magnetic line of force. We then revisit Maxwell's historical inspiration, namely Faraday's 1846 model of light as disturbances in lines of force. Using our unified model, we show that such disturbances resemble photons: they are polarised, absorbed discretely, obey Maxwell's full equations of electromagnetism to first order, and quantitatively reproduce the correlation that is observed in the Bell tests.

  20. Magnetic Monopole Bibliography-II

    E-Print Network [OSTI]

    S. Balestra; G. Giacomelli; M. Giorgini; L. Patrizii; V. Popa; Z. Sahnoun; V. Togo

    2011-05-27T23:59:59.000Z

    The bibliography compilation on magnetic monopoles is updated to include references from 2000 till mid 2011. It is intended to contain all experimental papers on the subject and only the theoretical papers which have specific experimental implications.

  1. MO. REV. MO. MAGNETIC CLEANLINESS GUIDELINES

    E-Print Network [OSTI]

    Rathbun, Julie A.

    MO. REV. MO. ATM-865 MAGNETIC CLEANLINESS GUIDELINES PAGE 1 Of 3 DATE 4/6/70 The purpose of this ATM is to update the ALSEP Magnetic Cleanliness Guidelines as delineated in A TM-294, dated 1 June. ATM-865 MAGNETIC CLEANLINESS GUIDELINES PAGE 2 OF 3 DATE 4/6/70 A review of the ALSEP Magnetic

  2. Magnetic domains were not found in tetrataenite.

    E-Print Network [OSTI]

    Mountziaris, T. J.

    collaboration with electrical engineers to produce the proper magnetic tape to view domains in. Observing and Industrial Engineering, University of Massachusetts, Amherst, MA 01003 Future Work While the magnetism· Magnetic domains were not found in tetrataenite. · Figure 4 shows magnetic domains found

  3. Ames Lab 101: Ultrafast Magnetic Switching

    ScienceCinema (OSTI)

    Jigang Wang

    2013-06-05T23:59:59.000Z

    Ames Laboratory physicists have found a new way to switch magnetism that is at least 1000 times faster than currently used in magnetic memory technologies. Magnetic switching is used to encode information in hard drives, magnetic random access memory and other computing devices. The discovery potentially opens the door to terahertz and faster memory speeds.

  4. Magnetic Reconnection 6.1 Introduction

    E-Print Network [OSTI]

    Priest, Eric

    6 Magnetic Reconnection 6.1 Introduction Magnetic reconnection is a fundamental process or slow (in a sense defined below), although in many dynamic phenomena such as solar flares it is fast. The main effects of magnetic reconnection are often: (i) to convert some of the magnetic energy into heat

  5. MAGNETIC EXPERIMENTS1,2 INTRODUCTION

    E-Print Network [OSTI]

    APPENDIX 47 APPENDIX MAGNETIC EXPERIMENTS1,2 INTRODUCTION As noted in the Handbook for Shipboard is a vertically downward magnetization, much of which is frequently an easily de- magnetized, or soft, magnetization removed by ~10-mT demagnetization. There is also sometimes a radially inward horizontal component

  6. LAMELLAR MAGNETISM ASSOCIATED WITH NANOSCALE EXSOLUTION

    E-Print Network [OSTI]

    Dunin-Borkowski, Rafal E.

    LAMELLAR MAGNETISM ASSOCIATED WITH NANOSCALE EXSOLUTION IN THE ILMENITE-HEMATITE SOLID SOLUTION-hematite (FeTiO3-Fe2O3) solid solution is one of the most important magnetic phases in nature. Unusual magnetic, magnetic ordering, and exsolution. This presentation describes how this interaction leads to the phenomenon

  7. Stellar Explosions by Magnetic Towers

    E-Print Network [OSTI]

    Dmitri A. Uzdensky; Andrew I. MacFadyen

    2006-05-05T23:59:59.000Z

    We propose a magnetic mechanism for the collimated explosion of a massive star relevant for GRBs, XRFs and asymmetric supernovae. We apply Lynden-Bell's magnetic tower scenario to the interior of a massive rotating star after the core has collapsed to form a black hole with an accretion disk or a millisecond magnetar acting as a central engine. We solve the force-free Grad-Shafranov equation to calculate the magnetic structure and growth of a tower embedded in a stellar environment. The pressure of the toroidal magnetic field, continuously generated by differential rotation of the central engine, drives a rapid expansion which becomes vertically collimated after lateral force balance with the surrounding gas pressure is reached. The collimation naturally occurs because hoop stress concentrates magnetic field toward the rotation axis and inhibits lateral expansion. This leads to the growth of a self-collimated magnetic tower. When embedded in a massive star, the supersonic expansion of the tower drives a strong bow shock behind which an over-pressured cocoon forms. The cocoon confines the tower by supplying collimating pressure and provides stabilization against disruption due to MHD instabilities. Because the tower consists of closed field lines starting and ending on the central engine, mixing of baryons from the cocoon into the tower is suppressed. The channel cleared by the growing tower is thus plausibly free of baryons and allows the escape of magnetic energy from the central engine through the star. While propagating down the stellar density gradient, the tower accelerates and becomes relativistic. During the expansion, fast collisionless reconnection becomes possible resulting in dissipation of magnetic energy which may be responsible for GRB prompt emission.

  8. Neutrino dispersion in magnetized plasma

    E-Print Network [OSTI]

    N. V. Mikheev; E. N. Narynskaya

    2008-12-02T23:59:59.000Z

    The neutrino dispersion in the charge symmetric magnetized plasma is investigated. We have studied the plasma contribution into the additional energy of neutrino and obtained the simple expression for it. We consider in detail the neutrino self-energy under physical conditions of weak field, moderate field and strong field limits. It is shown that our result for neutrino dispersion in moderate magnetic field differ substantially from the previous one in the literature.

  9. Compact magnetic energy storage module

    DOE Patents [OSTI]

    Prueitt, Melvin L. (Los Alamos, NM)

    1994-01-01T23:59:59.000Z

    A superconducting compact magnetic energy storage module in which a plurality of superconducting toroids, each having a toroidally wound superconducting winding inside a poloidally wound superconducting winding, are stacked so that the flow of electricity in each toroidally wound superconducting winding is in a direction opposite from the direction of electrical flow in other contiguous superconducting toroids. This allows for minimal magnetic pollution outside of the module.

  10. Compact magnetic energy storage module

    DOE Patents [OSTI]

    Prueitt, M.L.

    1994-12-20T23:59:59.000Z

    A superconducting compact magnetic energy storage module in which a plurality of superconducting toroids, each having a toroidally wound superconducting winding inside a poloidally wound superconducting winding, are stacked so that the flow of electricity in each toroidally wound superconducting winding is in a direction opposite from the direction of electrical flow in other contiguous superconducting toroids. This allows for minimal magnetic pollution outside of the module. 4 figures.

  11. Superconducting magnet for nuclei orientation

    E-Print Network [OSTI]

    Wang, Fa-Chung

    1968-01-01T23:59:59.000Z

    SUPERCOMDUCTING MAGNET FOR NUCLEI ORIENTATION A . Thesis Pa-Chung Wang Submitted. to the Graduate Co11ege of the Texas AEON University in partial fulfillment of the requirements for the degree of NASTEB OP SCIENCE Nay 1968 Nagor Sub...)cot: Physlos SUPEECOKDUCTING MAGNET FOE NUCLEI OBIENTATION A Thesis by Fa-Chung Wang Approved as to style and content byi (Chairman of Committee) Head of Department) Berber i ~ . /' (joe-ber) / f ~;: ( Niay 1968 + & 0 & z c. i ACKNOWLEDGENENTS...

  12. Writing magnetic patterns with surface acoustic waves

    SciTech Connect (OSTI)

    Li, Weiyang; Buford, Benjamin; Jander, Albrecht; Dhagat, Pallavi, E-mail: dhagat@eecs.oregonstate.edu [School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, Oregon 97331 (United States)

    2014-05-07T23:59:59.000Z

    A novel patterning technique that creates magnetization patterns in a continuous magnetostrictive film with surface acoustic waves is demonstrated. Patterns of 10??m wide stripes of alternating magnetization and a 3??m dot of reversed magnetization are written using standing and focusing acoustic waves, respectively. The magnetization pattern is size-tunable, erasable, and rewritable by changing the magnetic field and acoustic power. This versatility, along with its solid-state implementation (no moving parts) and electronic control, renders it as a promising technique for application in magnetic recording, magnonic signal processing, magnetic particle manipulation, and spatial magneto-optical modulation.

  13. High temperature magnetic properties of SmCo5/-Fe(Co) bulk nanocomposite magnets

    E-Print Network [OSTI]

    Liu, J. Ping

    High temperature magnetic properties of SmCo5/-Fe(Co) bulk nanocomposite magnets Chuanbing Rong://apl.aip.org/about/rights_and_permissions #12;High temperature magnetic properties of SmCo5/a-Fe(Co) bulk nanocomposite magnets Chuanbing Rong,1 containing no heavy rare earths for power applications, SmCo5/Fe bulk nanocomposite magnets with enhanced

  14. The measurement and analysis of the magnetic field of a synchrotron light source magnet 

    E-Print Network [OSTI]

    Graf, Udo Werner

    1994-01-01T23:59:59.000Z

    In this thesis a unique system is used to measure the magnetic field of a superconducting synchrotron light source magnet. The magnet measured is a superferric dipole C-magnet designed to produce a magnetic field up to 3 Tesla in magnitude. Its...

  15. Controlling a magnetic force microscope to track a magnetized nanosize particle

    E-Print Network [OSTI]

    Andersson, Sean B.

    1 Controlling a magnetic force microscope to track a magnetized nanosize particle Dimitar Baronov and Sean B. Andersson Abstract--In this paper, we introduce a scheme for tracking a magnetic nanoparticle moving in three-dimensions using a magnetic force microscope (MFM). The stray magnetic field

  16. ACCEPTANCE SUMMARY FOR LHC MAGNETS BUILT AT BNL Magnet D4L102

    E-Print Network [OSTI]

    Ohta, Shigemi

    the magnet's field quality. Engineering: Escallier reported via email that the magnet met the electricalACCEPTANCE SUMMARY FOR LHC MAGNETS BUILT AT BNL Magnet D4L102 Date of this summary: September 2 on September 2, 2004 and approved the magnet for shipment to CERN. On July 28, R. Ostojic reported that CERN

  17. ACCEPTANCE SUMMARY FOR LHC MAGNETS BUILT AT BNL Magnet: D2L105

    E-Print Network [OSTI]

    Ohta, Shigemi

    of this magnet to be satisfactory [1]. Engineering: Escallier reviewed the electrical tests of the magnetACCEPTANCE SUMMARY FOR LHC MAGNETS BUILT AT BNL Magnet: D2L105 Date of this summary: 20 August 2003 of the minutes, or as footnotes]. Acceptance Status: The BNL committee has approved the magnet for shipment

  18. Design and Analysis of a Nested Halbach Permanent Magnet Magnetic Refrigerator

    E-Print Network [OSTI]

    Victoria, University of

    Design and Analysis of a Nested Halbach Permanent Magnet Magnetic Refrigerator by Armando Tura BEng Committee Design and Analysis of a Nested Halbach Permanent Magnet Magnetic Refrigerator by Armando Tura with the potential to create efficient and compact refrigeration devices is an active magnetic regenerative

  19. MICE Spectrometer Magnet System Progress

    SciTech Connect (OSTI)

    Green, Michael A.; Virostek, Steve P.

    2007-08-27T23:59:59.000Z

    The first magnets for the muon ionization cooling experimentwill be the tracker solenoids that form the ends of the MICE coolingchannel. The primary purpose of the tracker solenoids is to provide auniform 4 T field (to better than +-0.3 percent over a volume that is 1meter long and 0.3 meters in diameter) spectrometer magnet field for thescintillating fiber detectors that are used to analyze the muons in thechannel before and after ionization cooling. A secondary purpose for thetracker magnet is the matching of the muon beam between the rest of theMICE cooling channel and the uniform field spectrometer magnet. Thetracker solenoid is powered by three 300 amp power supplies. Additionaltuning of the spectrometer is provided by a pair of 50 amp power suppliesacross the spectrometer magnet end coils. The tracker magnet will becooled using a pair of 4 K pulse tube coolers that each provide 1.5 W ofcooling at 4.2 K. Final design and construction of the tracker solenoidsbegan during the summer of 2006. This report describes the progress madeon the construction of the tracker solenoids.

  20. Magnetic Monopoles in Spin Ice

    E-Print Network [OSTI]

    Claudio Castelnovo; Roderich Moessner; Shivaji L. Sondhi

    2007-10-31T23:59:59.000Z

    Electrically charged particles, such as the electron, are ubiquitous. By contrast, no elementary particles with a net magnetic charge have ever been observed, despite intensive and prolonged searches. We pursue an alternative strategy, namely that of realising them not as elementary but rather as emergent particles, i.e., as manifestations of the correlations present in a strongly interacting many-body system. The most prominent examples of emergent quasiparticles are the ones with fractional electric charge e/3 in quantum Hall physics. Here we show that magnetic monopoles do emerge in a class of exotic magnets known collectively as spin ice: the dipole moment of the underlying electronic degrees of freedom fractionalises into monopoles. This enables us to account for a mysterious phase transition observed experimentally in spin ice in a magnetic field, which is a liquid-gas transition of the magnetic monopoles. These monopoles can also be detected by other means, e.g., in an experiment modelled after the celebrated Stanford magnetic monopole search.

  1. Optical sensor of magnetic fields

    DOE Patents [OSTI]

    Butler, M.A.; Martin, S.J.

    1986-03-25T23:59:59.000Z

    An optical magnetic field strength sensor for measuring the field strength of a magnetic field comprising a dilute magnetic semi-conductor probe having first and second ends, longitudinally positioned in the magnetic field for providing Faraday polarization rotation of light passing therethrough relative to the strength of the magnetic field. Light provided by a remote light source is propagated through an optical fiber coupler and a single optical fiber strand between the probe and the light source for providing a light path therebetween. A polarizer and an apparatus for rotating the polarization of the light is provided in the light path and a reflector is carried by the second end of the probe for reflecting the light back through the probe and thence through the polarizer to the optical coupler. A photo detector apparatus is operably connected to the optical coupler for detecting and measuring the intensity of the reflected light and comparing same to the light source intensity whereby the magnetic field strength may be calculated.

  2. Magnet Coil Shorted Turn Detector

    SciTech Connect (OSTI)

    Dinkel, J.A.; Biggs, J.E.

    1994-03-01T23:59:59.000Z

    The Magnet Coil Shorted Turn Detector has been developed to facilitate the location of shorted turns in magnet coils. Finding these shorted turns is necessary to determine failure modes that are a necessary step in developing future production techniques. Up to this point, coils with shorted turns had the insulation burned off without the fault having been located. This disassembly process destroyed any chance of being able to find the fault. In order to maintain a flux balance in a coupled system such as a magnet coil, the current in a shorted turn must be opposed to the incident current. If the direction of the current in each conductor can be measured relative to the incident current, then the exact location of the short can be determined. In this device, an AC voltage is applied to the magnet under test. A small hand held B-dot pickup coil monitors the magnetic field produced by current in the individual magnet conductors. The relative phase of this pickup coil voltage is compared to a reference signal derived from the input current to detect a current reversal as the B-dot pickup coil is swept over the conductors of the coil under test. This technique however, is limited to only those conductors that are accessible to the hand held probe.

  3. Signal enhancement using a switchable magnetic trap

    DOE Patents [OSTI]

    Beer, Neil Reginald (Pleasanton, CA)

    2012-05-29T23:59:59.000Z

    A system for analyzing a sample including providing a microchannel flow channel; associating the sample with magnetic nanoparticles or magnetic polystyrene-coated beads; moving the sample with said magnetic nanoparticles or magnetic polystyrene-coated beads in the microchannel flow channel; holding the sample with the magnetic nanoparticles or magnetic polystyrene-coated beads in a magnetic trap in the microchannel flow channel; and analyzing the sample obtaining an enhanced analysis signal. An apparatus for analysis of a sample includes magnetic particles connected to the sample, a microchip, a flow channel in the microchip, a source of carrier fluid connected to the flow channel for moving the sample in the flow channel, an electromagnet trap connected to the flow line for selectively magnetically trapping the sample and the magnetic particles, and an analyzer for analyzing the sample.

  4. Magnetic susceptibility and magnetization properties of asymmetric nuclear matter under a strong magnetic field

    E-Print Network [OSTI]

    A. Rabhi; M. A. Pérez-García; C. Providência; I. Vidaña

    2014-10-10T23:59:59.000Z

    We study the effect of a strong magnetic field on the proton and neutron spin polarization and magnetic susceptibility of asymmetric nuclear matter within a relativistic mean-field approach. It is shown that magnetic fields $B \\sim 10^{16} - 10^{17}$ G have already noticeable effects on the range of densities of interest for the study of the crust of a neutron star. Although the proton susceptibility is larger for weaker fields, the neutron susceptibility becomes of the same order or even larger for small proton fractions and subsaturation densities for $B > 10^{16}$ G. We expect that neutron superfluidity in the crust will be affected by the presence of magnetic fields.

  5. Magnetic response enhancement via electrically induced magnetic moments

    E-Print Network [OSTI]

    B. Jungnitsch; J. Evers

    2008-04-22T23:59:59.000Z

    The realization of negative refraction in atomic gases requires a strong magnetic response of the atoms. Current proposals for such systems achieve an enhancement of the magnetic response by a suitable laser field configuration, but still rely on high gas densities. Thus further progress is desirable, and this requires an understanding of the precise mechanism for the enhancement. Therefore, here we study the magnetic and electric response to a probe field interacting with three-level atoms in ladder configuration. In our first model, the three transitions are driven by a control field and the electric and magnetic component of the probe field, giving rise to a closed interaction loop. In a reference model, the coherent driving is replaced by an incoherent pump field. A time-dependent analysis of the closed-loop system enables us to identify the different contributions to the medium response. A comparison with the reference system then allows one to identify the physical mechanism that leads to the enhancement. It is found that the enhancement occurs at so-called multiphoton resonance by a scattering of the coupling field and the electric probe field mode into the magnetic probe field mode. Based on these results, conditions for the enhancement are discussed.

  6. Modeling spin magnetization transport in a spatially varying magnetic field

    E-Print Network [OSTI]

    Rico A. R. Picone; Joseph L. Garbini; John A. Sidles

    2014-08-13T23:59:59.000Z

    We present a framework for modeling the transport of any number of globally conserved quantities in any spatial configuration and apply it to obtain a model of magnetization transport for spin-systems that is valid in new regimes (including high-polarization). The framework allows an entropy function to define a model that explicitly respects the laws of thermodynamics. Three facets of the model are explored. First, it is expressed as nonlinear partial differential equations that are valid for the new regime of high dipole-energy and polarization. Second, the nonlinear model is explored in the limit of low dipole-energy (semi-linear), from which is derived a physical parameter characterizing separative magnetization transport (SMT). It is shown that the necessary and sufficient condition for SMT to occur is that the parameter is spatially inhomogeneous. Third, the high spin-temperature (linear) limit is shown to be equivalent to the model of nuclear spin transport of Genack and Redfield. Differences among the three forms of the model are illustrated by numerical solution with parameters corresponding to a magnetic resonance force microscopy (MRFM) experiment. A family of analytic, steady-state solutions to the nonlinear equation is derived and shown to be the spin-temperature analog of the Langevin paramagnetic equation and Curie's law. Finally, we analyze the separative quality of magnetization transport, and a steady-state solution for the magnetization is shown to be compatible with Fenske's separative mass transport equation.

  7. Small-scale magnetic buoyancy and magnetic pumping effects in a turbulent convection

    E-Print Network [OSTI]

    I. Rogachevskii; N. Kleeorin

    2006-05-18T23:59:59.000Z

    We determine the nonlinear drift velocities of the mean magnetic field and nonlinear turbulent magnetic diffusion in a turbulent convection. We show that the nonlinear drift velocities are caused by the three kinds of the inhomogeneities, i.e., inhomogeneous turbulence; the nonuniform fluid density and the nonuniform turbulent heat flux. The inhomogeneous turbulence results in the well-known turbulent diamagnetic and paramagnetic velocities. The nonlinear drift velocities of the mean magnetic field cause the small-scale magnetic buoyancy and magnetic pumping effects in the turbulent convection. These phenomena are different from the large-scale magnetic buoyancy and magnetic pumping effects which are due to the effect of the mean magnetic field on the large-scale density stratified fluid flow. The small-scale magnetic buoyancy and magnetic pumping can be stronger than these large-scale effects when the mean magnetic field is smaller than the equipartition field. We discuss the small-scale magnetic buoyancy and magnetic pumping effects in the context of the solar and stellar turbulent convection. We demonstrate also that the nonlinear turbulent magnetic diffusion in the turbulent convection is anisotropic even for a weak mean magnetic field. In particular, it is enhanced in the radial direction. The magnetic fluctuations due to the small-scale dynamo increase the turbulent magnetic diffusion of the toroidal component of the mean magnetic field, while they do not affect the turbulent magnetic diffusion of the poloidal field.

  8. Thermodynamic and transport properties of non-magnetic particles in magnetic fluids

    E-Print Network [OSTI]

    Tejwani, Saurabh

    2009-01-01T23:59:59.000Z

    Magnetic composites, obtained on associating magnetic fluid with non-magnetic particles, offer interesting opportunities in separations, assemblies and other applications, where the microstructure of the composite can be ...

  9. Magnetic Exchange Coupling and Single-Molecule Magnetism in Uranium Complexes

    E-Print Network [OSTI]

    Rinehart, Jeffrey Dennis

    2010-01-01T23:59:59.000Z

    J. -P. ; Kahn, M. L. In Magnetism: Molecules to Materials V.R. Simple Models of Magnetism; Oxford University Press:for interpreting uranium magnetism and will be discussed in

  10. Dynamic control of spin states in interacting magnetic elements

    DOE Patents [OSTI]

    Jain, Shikha; Novosad, Valentyn

    2014-10-07T23:59:59.000Z

    A method for the control of the magnetic states of interacting magnetic elements comprising providing a magnetic structure with a plurality of interacting magnetic elements. The magnetic structure comprises a plurality of magnetic states based on the state of each interacting magnetic element. The desired magnetic state of the magnetic structure is determined. The active resonance frequency and amplitude curve of the desired magnetic state is determined. Each magnetic element of the magnetic structure is then subjected to an alternating magnetic field or electrical current having a frequency and amplitude below the active resonance frequency and amplitude curve of said desired magnetic state and above the active resonance frequency and amplitude curve of the current state of the magnetic structure until the magnetic state of the magnetic structure is at the desired magnetic state.

  11. High performance magnetic bearing systems using high temperature superconductors

    DOE Patents [OSTI]

    Abboud, Robert G. (Barrington Hills, IL)

    1998-01-01T23:59:59.000Z

    A magnetic bearing apparatus and a method for providing at least one stabilizing force in a magnetic bearing structure with a superconducting magnetic assembly and a magnetic assembly, by providing a superconducting magnetic member in the superconducting magnetic assembly with a plurality of domains and arranging said superconducting magnetic member such that at least one domain has a domain C-axis vector alignment angularly disposed relative to a reference axis of the magnetic member in the magnetic assembly.

  12. High performance magnetic bearing systems using high temperature superconductors

    DOE Patents [OSTI]

    Abboud, R.G.

    1998-05-05T23:59:59.000Z

    Disclosed are a magnetic bearing apparatus and a method for providing at least one stabilizing force in a magnetic bearing structure with a superconducting magnetic assembly and a magnetic assembly, by providing a superconducting magnetic member in the superconducting magnetic assembly with a plurality of domains and arranging said superconducting magnetic member such that at least one domain has a domain C-axis vector alignment angularly disposed relative to a reference axis of the magnetic member in the magnetic assembly. 7 figs.

  13. Target Plasma Formation for Magnetic Compression/Magnetized Target Fusion

    SciTech Connect (OSTI)

    Lindemuth, I.R.; Reinovsky, R.E.; Chrien, R.E.; Christian, J.M.; Ekdahl, C.A.; Goforth, J.H.; Haight, R.C.; Idzorek, G.; King, N.S.; Kirkpatrick, R.C.; Larson, R.E.; Morgan, G.L.; Olinger, B.W.; Oona, H.; Sheehey, P.T.; Shlachter, J.S.; Smith, R.C.; Veeser, L.R.; Warthen, B.J.; Younger, S.M. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Chernyshev, V.K.; Mokhov, V.N.; Demin, A.N.; Dolin, Y.N.; Garanin, S.F.; Ivanov, V.A.; Korchagin, V.P.; Mikhailov, O.D.; Morozov, I.V.; Pak, S.V.; Pavlovskii, E.S.; Seleznev, N.Y.; Skobelev, A.N.; Volkov, G.I.; Yakubov, V.A. [All-Russian Scientific Research Institute of Experimental Physics, Arzamas-16 (Russian Federation)] [All-Russian Scientific Research Institute of Experimental Physics, Arzamas-16 (Russian Federation)

    1995-09-04T23:59:59.000Z

    Experimental observations of plasma behavior in a novel plasma formation chamber are reported. Experimental results are in reasonable agreement with two-dimensional magnetohydrodynamic computations suggesting that the plasma could subsequently be adiabatically compressed by a magnetically driven pusher to yield 1 GJ of fusion energy. An explosively driven helical flux compression generator mated with a unique closing switch/opening switch combination delivered a 2.7 MA, 347 {mu}s magnetization current and an additional 5 MA, 2.5 {mu}s electrical pulse to the chamber. A hot plasma was produced and 10{sup 13} D-T fusion reactions were observed.

  14. Electric control of magnetization relaxation in thin film magnetic insulators.

    SciTech Connect (OSTI)

    Wang, Z.; Sun, Y.; Song, Y-Y.; Wu, M.; Schultheiss, H.; Pearson, J. E.; Hoffmann, A. (Materials Science Division); (Colorado State Univ.)

    2011-10-01T23:59:59.000Z

    Control of magnetization relaxation in magnetic insulators via interfacial spin scattering is demonstrated. The experiments use nanometer-thick yttrium iron garnet (YIG)/Pt layered structures, with the Pt layer biased by an electric voltage. The bias voltage produces a spin current across the Pt thickness. As this current scatters off the YIG surface, it exerts a torque on the YIG surface spins. This torque can reduce or enhance the damping and thereby decrease or increase the ferromagnetic resonance linewidth of the YIG film, depending on the field/current configuration.

  15. asymmetric magnetic perturbations: Topics by E-print Network

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

    magnetic field side because energetic particles are more likely to escape the magnetic mirror. The footpoint on the weak magnetic field side is predicted to move more quickly...

  16. Networking with Clinical Nurses: Fusing Magnet & Organizational Missions

    E-Print Network [OSTI]

    Wickline, Mary

    2009-01-01T23:59:59.000Z

    Nurses: Fusing Magnet & Organizational Missions © MaryFusing Magnet & Organizational Missions Mary Wickline, MLIS,Nurses: Fusing Magnet & Organizational Missions © Mary

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

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

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

  18. Interface-induced magnetism in perovskite quantum wells

    E-Print Network [OSTI]

    Jackson, Clayton A; Stemmer, Susanne

    2013-01-01T23:59:59.000Z

    INTERFACE-INDUCED MAGNETISM IN PEROVSKITE . . . PHYSICALR) (2013) Interface-induced magnetism in perovskite quantumelectron gases, and magnetism can all be found in a single

  19. Rock magnetism of remagnetized carbonate rocks: another look

    E-Print Network [OSTI]

    Jackson, M.; Swanson-Hysell, N. L

    2012-01-01T23:59:59.000Z

    and significance of magnetism in sedimentary rocks. Journal1997. Rock Magnetism. ¨ zdemir, O Dunlop, D. J. & Oon July 30, 2013 ROCK MAGNETISM: REMAGNETIZED CARBONATES

  20. Flipping the switch on magnetism in strontium titanate

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

    Flipping the switch on magnetism in strontium titanate Flipping the switch on magnetism in strontium titanate Researchers have found a way to magnetize this material using light,...

  1. Watermelon-like iron nanoparticles: Cr doping effect on magnetism...

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

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

  2. Electrically Controllable Spontaneous Magnetism in Nanoscale Mixed Phase Multiferroics

    E-Print Network [OSTI]

    He, Q.

    2011-01-01T23:59:59.000Z

    Controllable Spontaneous Magnetism in Nanoscale Mixed Phase2001). Chakhalian, J. et al. Magnetism at the interfacelocal nature of this magnetism. We find that the spontaneous

  3. Magnetic refrigeration apparatus with heat pipes

    DOE Patents [OSTI]

    Barclay, J.A.; Prenger, F.C. Jr.

    1985-10-25T23:59:59.000Z

    A magnetic refrigerator operating in the 4 to 20 K range utilizes heat pipes to transfer heat to and from the magnetic material at the appropriate points during the material's movement. In one embodiment circular disks of magnetic material can be interleaved with the ends of the heat pipes. In another embodiment a mass of magnetic material reciprocatingly moves between the end of the heat pipe or pipes that transmits heat from the object of cooling to the magnetic material and the end of the heat pipe or pipes that transmits heat from the magnetic material to a heat sink.

  4. Magnetic refrigeration apparatus with heat pipes

    DOE Patents [OSTI]

    Barclay, John A. (Los Alamos, NM); Prenger, Jr., F. Coyne (Madison, WI)

    1987-01-01T23:59:59.000Z

    A magnetic refrigerator operating in the 4 to 20 K range utilizes heat pipes to transfer heat to and from the magnetic material at the appropriate points during the material's movement. In one embodiment circular disks of magnetic material can be interleaved with the ends of the heat pipes. In another embodiment a mass of magnetic material reciprocatingly moves between the end of the heat pipe of pipes that transmits heat from the object of cooling to the magnetic material and the end of the heat pipe or pipes that transmits heat from the magnetic material to a heat sink.

  5. Thermalization in External Magnetic Field

    E-Print Network [OSTI]

    Ali-Akbari, Mohammad

    2012-01-01T23:59:59.000Z

    In the AdS/CFT framework meson thermalization in the presence of a constant external magnetic field in a strongly coupled gauge theory has been studied. In the gravitational description the thermalization of mesons corresponds to the horizon formation on the flavour D7-brane which is embedded in the AdS_5 x S^5 background in the probe limit. The apparent horizon forms due to the time-dependent change in the baryon number chemical potential, the injection of baryons in the gauge theory. We will numerically show that the thermalization happens even faster in the presence of the magnetic field on the probe brane. We observe that this reduction in the thermalization time sustains up to a specific value of the magnetic field.

  6. Laminated magnet field coil sheath

    DOE Patents [OSTI]

    Skaritka, J.R.

    1987-05-15T23:59:59.000Z

    A method for manufacturing a magnetic cable trim coil in a sheath assembly for use in a cryogenic particle accelerator. A precisely positioned pattern of trim coil turns is bonded to a flexible substrate sheath that is capable of withstanding cryogenic operating conditions. In the method of the invention the flexible substrate sheath, with the trim coil pattern precisely location relative to a bore tube assembly of an accelerator and is then bonded to the bore tube with a tape suitable for cryogenic application. The resultant assembly can be readily handled and installed within an iron magnet yoke assembly of a suitable cryogenic particle accelerator. 1 fig.

  7. Laminated magnet field coil sheath

    DOE Patents [OSTI]

    Skaritka, John R. (Coram, NY)

    1987-12-01T23:59:59.000Z

    a method for manufacturing a magnet cable trim coil in a sheath assembly for use in a cryogenic particle accelerator. A precisely positioned pattern of trim coil turns is bonded to a flexible substrate sheath that is capable of withstanding cryogenic operating conditions. In the method of the invention the flexible sheath, with the trim coil pattern precisely positioned thereon, is accurately positioned at a precise location relative to a bore tube assembly of an accelerator and is then bonded to the bore tube with a tape suitable for cryogenic application. The resultant assembly can be readily handled and installed within an iron magnet yoke assembly of a suitable cryogenic particle accelerator.

  8. Wheel-type magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, John A. (Los Alamos, NM)

    1983-01-01T23:59:59.000Z

    The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load.

  9. Wheel-type magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, J.A.

    1982-01-20T23:59:59.000Z

    The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load.

  10. Wheel-type magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, J.A.

    1983-10-11T23:59:59.000Z

    The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load. 7 figs.

  11. The Cost of Superconducting Magnets as a Function of Stored Energy and Design Magnetic Induction Times the Field Volume

    E-Print Network [OSTI]

    Green, M.A.

    2008-01-01T23:59:59.000Z

    the Cost of Large Superconducting Thin Solenoid Magnets,"The Economics of Large Superconducting Toroidal Magnets forEnergy (MJ) Fig. 2. Superconducting magnet costs (M$) versus

  12. Chapter 20. Magnetic Resonance Imaging Magnetic Resonance Imaging

    E-Print Network [OSTI]

    , and software training from Siemens Medical Solutions; research funding through the Siemens-MIT Alliance and Technology (HST). 2 Siemens Medical Solutions, Erlangen, Germany. #12;Chapter 20. Magnetic Resonance Imaging, Siemens Medical Solutions, Siemens-MIT Alliance, HST Martinos Catalyst Fund. Project Staff: Audrey P. Fan

  13. A GLOBAL MAGNETIC TOPOLOGY MODEL FOR MAGNETIC CLOUDS. I

    SciTech Connect (OSTI)

    Hidalgo, M. A. [Departamento de Fisica, Universidad de Alcala (Spain); Nieves-Chinchilla, T., E-mail: miguel.hidalgo@uah.es, E-mail: teresa.nieves-chinchil-1@nasa.gov [Institute for Astrophysics and Computational Sciences Catholic University of America, Washington, DC (United States)

    2012-04-01T23:59:59.000Z

    We present an analytical approach to the global magnetic field topology of magnetic clouds (MCs) that considers them like close magnetic structures with torus geometry and with a non-uniform (variable maximum radius) cross section along them. Following our previous approach to the problem of MCs (Hidalgo 2003, 2011), we establish an intrinsic coordinate system for that topology, and then we analytically solve the Maxwell equations in terms of it. The purpose of the present work is to present this model, which will lead us to understand in a more realistic way the physical mechanisms inside MCs. The model has a non-force-free character and also takes into account the time evolution of the cross sections of the MCs in their movement through the interplanetary medium. In this first paper, we obtain the expressions for the components of the magnetic field and the plasma current density imposing a large mean radius of the torus, and imposing a circular cross section with a variable maximum radius. Eventually, we fit the model to data related to four well-known MCs measurements at 1 AU, (three of them with circular cross sections and without expansion, as it is deduced from the experimental data). We compare the results of this toroidal model with those obtained with our previous cylindrical circular cross section model, also with a non-force-free character.

  14. Bioinspired synthesis of magnetic nanoparticles

    SciTech Connect (OSTI)

    David, Anand

    2009-05-26T23:59:59.000Z

    The synthesis of magnetic nanoparticles has long been an area of active research. Magnetic nanoparticles can be used in a wide variety of applications such as magnetic inks, magnetic memory devices, drug delivery, magnetic resonance imaging (MRI) contrast agents, and pathogen detection in foods. In applications such as MRI, particle uniformity is particularly crucial, as is the magnetic response of the particles. Uniform magnetic particles with good magnetic properties are therefore required. One particularly effective technique for synthesizing nanoparticles involves biomineralization, which is a naturally occurring process that can produce highly complex nanostructures. Also, the technique involves mild conditions (ambient temperature and close to neutral pH) that make this approach suitable for a wide variety of materials. The term 'bioinspired' is important because biomineralization research is inspired by the naturally occurring process, which occurs in certain microorganisms called 'magnetotactic bacteria'. Magnetotactic bacteria use biomineralization proteins to produce magnetite crystals having very good uniformity in size and morphology. The bacteria use these magnetic particles to navigate according to external magnetic fields. Because these bacteria synthesize high quality crystals, research has focused on imitating aspects of this biomineralization in vitro. In particular, a biomineralization iron-binding protein found in a certain species of magnetotactic bacteria, magnetospirillum magneticum, AMB-1, has been extracted and used for in vitro magnetite synthesis; Pluronic F127 gel was used to increase the viscosity of the reaction medium to better mimic the conditions in the bacteria. It was shown that the biomineralization protein mms6 was able to facilitate uniform magnetite synthesis. In addition, a similar biomineralization process using mms6 and a shorter version of this protein, C25, has been used to synthesize cobalt ferrite particles. The overall goal of this project is to understand the mechanism of magnetite particle synthesis in the presence of the biomineralization proteins, mms6 and C25. Previous work has hypothesized that the mms6 protein helps to template magnetite and cobalt ferrite particle synthesis and that the C25 protein templates cobalt ferrite formation. However, the effect of parameters such as the protein concentration on the particle formation is still unknown. It is expected that the protein concentration significantly affects the nucleation and growth of magnetite. Since the protein provides iron-binding sites, it is expected that magnetite crystals would nucleate at those sites. In addition, in the previous work, the reaction medium after completion of the reaction was in the solution phase, and magnetic particles had a tendency to fall to the bottom of the medium and aggregate. The research presented in this thesis involves solid Pluronic gel phase reactions, which can be studied readily using small-angle x-ray scattering, which is not possible for the solution phase experiments. In addition, the concentration effect of both of the proteins on magnetite crystal formation was studied.

  15. Manipulation and sorting of magnetic particles by a magnetic force microscope on a microfluidic magnetic trap platform

    E-Print Network [OSTI]

    Donahue, Michael J.

    1 Manipulation and sorting of magnetic particles by a magnetic force microscope on a microfluidic magnetic trap platform Elizabeth Mirowski, John Moreland, Arthur Zhang and Stephen E. Russek Electronics and Electrical Engineering Laboratory, National Institute of Standards and Technology, Boulder, CO 80305 Michael

  16. Detrital remanent magnetization in the solar nebula

    E-Print Network [OSTI]

    Fu, Roger Rennan

    We introduce the theoretical basis of a new form of remanent magnetization that likely formed on primitive bodies in the solar system. Accretional detrital remanent magnetization (ADRM) operates via “compass needle”-type ...

  17. Magnetic switch for reactor control rod. [LMFBR

    DOE Patents [OSTI]

    Germer, J.H.

    1982-09-30T23:59:59.000Z

    A magnetic reed switch assembly is described for activating an electromagnetic grapple utilized to hold a control rod in position above a reactor core. In normal operation the magnetic field of a permanent magnet is short-circuited by a magnetic shunt, diverting the magnetic field away from the reed switch. The magnetic shunt is made of a material having a Curie-point at the desired release temperature. Above that temperature the material loses its ferromagnetic properties, and the magnetic path is diverted to the reed switch which closes and short-circuits the control circuit for the control rod electro-magnetic grapple which allows the control rod to drop into the reactor core for controlling the reactivity of the core.

  18. Magnetic bearing element with adjustable stiffness

    DOE Patents [OSTI]

    Post, Richard F

    2013-11-12T23:59:59.000Z

    A compact magnetic bearing element is provided which is made of permanent magnet discs configured to be capable of the adjustment of the bearing stiffness and levitation force over a wide range.

  19. Ames Lab 101: Rare-Earth Magnets

    ScienceCinema (OSTI)

    McCallum, Bill

    2012-08-29T23:59:59.000Z

    Senior Scientist, Bill McCallum, briefly discusses rare-earth magnets and their uses and how Ames Lab is research new ways to save money and energy using magnets.

  20. Magnetic properties in graphene-graphane superlattices

    E-Print Network [OSTI]

    Lee, Joo-Hyoung

    The magnetic properties of graphene-graphane superlattices with zigzag interfaces and separately varying widths are investigated by first-principles density functional calculations. It is demonstrated that magnetic states ...

  1. Platinum dendritic nanoparticles with magnetic behavior

    SciTech Connect (OSTI)

    Li, Wenxian, E-mail: wl240@uowmail.edu.au [Institute for Superconducting and Electronic Materials, University of Wollongong, NSW 2522 (Australia); Solar Energy Technologies, School of Computing, Engineering, and Mathematics, University of Western Sydney, Penrith NSW 2751 (Australia); Sun, Ziqi; Nevirkovets, Ivan P.; Dou, Shi-Xue [Institute for Superconducting and Electronic Materials, University of Wollongong, NSW 2522 (Australia); Tian, Dongliang [Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of the Ministry of Education, School of Chemistry and the Environment, Beihang University, Beijing 100191 (China)

    2014-07-21T23:59:59.000Z

    Magnetic nanoparticles have attracted increasing attention for biomedical applications in magnetic resonance imaging, high frequency magnetic field hyperthermia therapies, and magnetic-field-gradient-targeted drug delivery. In this study, three-dimensional (3D) platinum nanostructures with large surface area that features magnetic behavior have been demonstrated. The well-developed 3D nanodendrites consist of plentiful interconnected nano-arms ?4?nm in size. The magnetic behavior of the 3D dendritic Pt nanoparticles is contributed by the localization of surface electrons due to strongly bonded oxygen/Pluronic F127 and the local magnetic moment induced by oxygen vacancies on the neighboring Pt and O atoms. The magnetization of the nanoparticles exhibits a mixed paramagnetic and ferromagnetic state, originating from the core and surface, respectively. The 3D nanodendrite structure is suitable for surface modification and high amounts of drug loading if the transition temperature was enhanced to room temperature properly.

  2. Magnetic domain walls driven by interfacial phenomena

    E-Print Network [OSTI]

    Emori, Satoru

    2014-01-01T23:59:59.000Z

    A domain wall in a ferromagnetic material is a boundary between differently magnetized regions, and its motion provides a convenient scheme to control the magnetization state of the material. Domain walls can be confined ...

  3. Bipolar pulse field for magnetic refrigeration

    DOE Patents [OSTI]

    Lubell, Martin S. (Oak Ridge, TN)

    1994-01-01T23:59:59.000Z

    A magnetic refrigeration apparatus includes first and second steady state magnets, each having a field of substantially equal strength and opposite polarity, first and second bodies made of magnetocaloric material disposed respectively in the influence of the fields of the first and second steady state magnets, and a pulsed magnet, concentric with the first and second steady state magnets, and having a field which cycles between the fields of the first and second steady state magnets, thereby cyclically magnetizing and demagnetizing and thus heating and cooling the first and second bodies. Heat exchange apparatus of suitable design can be used to expose a working fluid to the first and second bodies of magnetocaloric material. A controller is provided to synchronize the flow of working fluid with the changing states of magnetization of the first and second bodies.

  4. Bipolar pulse field for magnetic refrigeration

    DOE Patents [OSTI]

    Lubell, M.S.

    1994-10-25T23:59:59.000Z

    A magnetic refrigeration apparatus includes first and second steady state magnets, each having a field of substantially equal strength and opposite polarity, first and second bodies made of magnetocaloric material disposed respectively in the influence of the fields of the first and second steady state magnets, and a pulsed magnet, concentric with the first and second steady state magnets, and having a field which cycles between the fields of the first and second steady state magnets, thereby cyclically magnetizing and demagnetizing and thus heating and cooling the first and second bodies. Heat exchange apparatus of suitable design can be used to expose a working fluid to the first and second bodies of magnetocaloric material. A controller is provided to synchronize the flow of working fluid with the changing states of magnetization of the first and second bodies. 2 figs.

  5. HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS

    E-Print Network [OSTI]

    Taylor, C.

    2011-01-01T23:59:59.000Z

    D. C. 'Niobium-Titanium Superconducting Material s ', in S.14, 1982 HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS C.SUMAG-68 HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS* C.

  6. Magnetic chicane for terahertz management

    DOE Patents [OSTI]

    Benson, Stephen (Yorktown, VA); Biallas, George Herman (Yorktown, VA); Douglas, David (Yorktown, VA); Jordan, Kevin Carl (Newport News, VA); Neil, George R. (Williamsburg, VA); Michelle D. Shinn (Newport News, VA); Willams, Gwyn P. (Yorktown, VA)

    2010-12-28T23:59:59.000Z

    The introduction of a magnetic electron beam orbit chicane between the wiggler and the downstream initial bending dipole in an energy recovering Linac alleviates the effects of radiation propagated from the downstream bending dipole that tend to distort the proximate downstream mirror of the optical cavity resonator.

  7. STRONGLY DISORDERED MAGNETS AND SUPERCONDUCTORS

    E-Print Network [OSTI]

    Fominov, Yakov

    STRONGLY DISORDERED MAGNETS AND SUPERCONDUCTORS: SOLUTION ON BETHE LATTICE. 1. Very brief summary. Bethe lattice model: toy model for SIT transition in disordered superconductors. 5. Solution of Bethe. Collaborators: M. Feigelman, M. Mezard. #12;ALTERNATIVE SCENARIOS OF SUPERCONDUCTOR-INSULATOR TRANSITIONS Fermi

  8. Oxime based manganese molecular magnets 

    E-Print Network [OSTI]

    Inglis, Ross

    2010-01-01T23:59:59.000Z

    The synthesis and characterisation of a large family of hexametallic [MnIII 6] Single-Molecule Magnets with general formula [MnIII 6O2(R-sao)6(X)2(L)4-6] (where sao2- = dianion of salicylaldoxime; R = H, Me, Et, Ph; X ...

  9. Magnetically coupled system for mixing

    SciTech Connect (OSTI)

    Miller, III, Harlan; Meichel, George; Legere, Edward; Malkiel, Edwin; Woods, Robert Paul; Ashley, Oliver; Katz, Joseph; Ward, Jason; Petersen, Paul

    2014-04-01T23:59:59.000Z

    The invention provides a mixing system comprising a magnetically coupled drive system and a foil for cultivating algae, or cyanobacteria, in an open or enclosed vessel. The invention provides effective mixing, low energy usage, low capital expenditure, and ease of drive system component maintenance while maintaining the integrity of a sealed mixing vessel.

  10. Turbulence and Magnetic Fields in Clouds

    E-Print Network [OSTI]

    Shantanu Basu

    2004-11-15T23:59:59.000Z

    We discuss several categories of models which may explain the IMF, including the possible role of turbulence and magnetic fields.

  11. Magnetic field topology of accreting white dwarfs

    E-Print Network [OSTI]

    Klaus Reinsch; Fabian Euchner; Klaus Beuermann; Stefan Jordan

    2003-02-04T23:59:59.000Z

    We report first results of our systematic investigation of the magnetic field structure of rotating single magnetic white dwarfs and of white dwarfs in magnetic cataclysmic variables. The global magnetic field distributions on the isolated white dwarf HE1045-0908 and the accreting white dwarfs in EF Eri and CP Tuc have been derived from phase-resolved flux and polarization spectra obtained with FORS1 at the ESO VLT using the systematic method of Zeeman tomography.

  12. Magnetic induction systems to harvest energy from mechanical vibrations

    E-Print Network [OSTI]

    Jonnalagadda, Aparna S

    2007-01-01T23:59:59.000Z

    This thesis documents the design process for magnetic induction systems to harvest energy from mechanical vibrations. Two styles of magnetic induction systems - magnet-through-coil and magnet-across-coils - were analyzed. ...

  13. ACCEPTANCE SUMMARY FOR LHC MAGNETS BUILT AT BNL Magnet D2L109

    E-Print Network [OSTI]

    Ohta, Shigemi

    is at the Web address given above.) Pilat approved the magnet's field quality. Engineering: Escallier reportedACCEPTANCE SUMMARY FOR LHC MAGNETS BUILT AT BNL Magnet D2L109 Date of this summary: 1 July 2005 of the minutes, or as footnotes]. Acceptance status: The BNL magnetic acceptance committee has approved

  14. ACCEPTANCE SUMMARY FOR LHC MAGNETS BUILT AT BNL Magnet D2L103

    E-Print Network [OSTI]

    Ohta, Shigemi

    reviewed the field quality data after the meeting and then approved the magnet [2]. Engineering: EscallierACCEPTANCE SUMMARY FOR LHC MAGNETS BUILT AT BNL Magnet D2L103 Date of this summary: 27 January 2005 of the minutes, or as footnotes]. Acceptance status: The magnet has been approved for acceptance. The field

  15. Magnetic Propulsion of Intense Lithium Streams in a Tokamak Magnetic Field

    E-Print Network [OSTI]

    Zakharov, Leonid E.

    Magnetic Propulsion of Intense Lithium Streams in a Tokamak Magnetic Field Leonid E. Zakharov the theory of magnetic propulsion of liquid lithium streams and their stability in tokamaks takes into account the propulsion e#11;ect, viscosity and the drag force due to magnetic pumping

  16. Wireless Control of Magnetic Helical Microrobots using a Rotating-Permanent-Magnet Manipulator

    E-Print Network [OSTI]

    Bamberg, Stacy Morris

    ]. Helical propulsion using magnetic fields is particularly promising for medical microrobots. HelicalWireless Control of Magnetic Helical Microrobots using a Rotating-Permanent-Magnet Manipulator Thomas W. R. Fountain, Prem V. Kailat, and Jake J. Abbott Abstract-- Magnetic helical medical microrobots

  17. 3060 IEEE TRANSACTIONS ON MAGNETICS, VOL. 40, NO. 4, JULY 2004 Vertically Laminated Magnetic Cores by

    E-Print Network [OSTI]

    laminated, electrodeposited Ni-Fe magnetic cores in microma- chined silicon for the low megahertz frequency--Eddy currents, magnetic cores, MEMS, microma- chining, nickel alloys, permalloy. I. INTRODUCTION ELECTROPLATED electrodeposition of magnetic and sacrificial metal layers [3]; alternating sputtering of thin-film magnetic

  18. NONLINEAR MAGNETIC LEVITATION OF AUTOMOTIVE ENGINE VALVES

    E-Print Network [OSTI]

    Stefanopoulou, Anna

    NONLINEAR MAGNETIC LEVITATION OF AUTOMOTIVE ENGINE VALVES K. Peterson, J.W. Grizzle, and A.G. Stefanopoulou £ ½ £ University of Michigan, Ann Arbor Abstract: Position regulation of a magnetic levitation the region of attraction. The effects of magnetic saturation are included in the model, and accounted

  19. Magnetic multipole redirector of moving plasmas

    DOE Patents [OSTI]

    Crow, James T. (Albuquerque, NM); Mowrer, Gary R. (Cedar Crest, NM)

    1999-01-01T23:59:59.000Z

    A method and apparatus for redirecting moving plasma streams using a multiple array of magnetic field generators (e.g., permanent magnets or current bearing wires). Alternate rows of the array have opposite magnetic field directions. A fine wire mesh may be employed to focus as well as redirect the plasma.

  20. CORONAL MAGNETIC FIELD MEASUREMENTS THROUGH GYRORESONANCE EMISSION

    E-Print Network [OSTI]

    White, Stephen

    Chapter 5 CORONAL MAGNETIC FIELD MEASUREMENTS THROUGH GYRORESONANCE EMISSION Stephen M. White This article reviews the use of gyroresonance emission at radio wavelengths to measure coronal magnetic fields. Keywords: Sun, solar corona, solar magnetic fields, solar radio emission Introduction Since the realization

  1. Magnetic QCA systems G.H. Bernsteina,

    E-Print Network [OSTI]

    Metlushko, Vitali

    Magnetic QCA systems G.H. Bernsteina, *, A. Imrea , V. Metlushkoc , A. Orlova , L. Zhoua , L. Jia in an altogether new paradigm. Magnetic interactions between nanomagnets are sufficiently strong to allow room recent work of the Notre Dame group on magnetically coupled QCA. q 2005 Elsevier Ltd. All rights reserved

  2. Novel Magnetic Hydrogen Sensing: A Case Study Using Antiferromagnetic...

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

    Magnetic Hydrogen Sensing: A Case Study Using Antiferromagnetic Hematite Nanoparticles. Novel Magnetic Hydrogen Sensing: A Case Study Using Antiferromagnetic Hematite...

  3. Progress on Superconducting Magnets for the MICE Cooling Channel

    E-Print Network [OSTI]

    Green, Michael A

    2010-01-01T23:59:59.000Z

    the MICE cooling channel magnets and the progress in theProgress on the Superconducting Magnets for the MICE Cooling

  4. Soft X-ray techniques to study mesoscale magnetism

    E-Print Network [OSTI]

    Kortright, Jeffrey B.

    2003-01-01T23:59:59.000Z

    X-Ray Techniques to Study Mesoscale Magnetism Jeffrey B.X-Ray Techniques to Study Mesoscale Magnetism Jeffrey B.

  5. Strain broadening of the magnetization steps in diluted magnetic semiconductors Yuri G. Rubo* and M. F. Thorpe

    E-Print Network [OSTI]

    Thorpe, Michael

    Strain broadening of the magnetization steps in diluted magnetic semiconductors Yuri G. Rubo* and M alloys diluted magnetic semiconductors results in fluctuations of the exchange constants between semiconducting alloys, the so- called semimagnetic semiconductors or diluted magnetic semiconductors DMS

  6. Local geometrical properties of magnetic configurations with nested equilibrium magnetic surfaces

    SciTech Connect (OSTI)

    Skovoroda, A. A. [Russian Research Centre Kurchatov Institute, Nuclear Fusion Institute (Russian Federation)

    2009-04-15T23:59:59.000Z

    The complete set of universal local relationships between geometrical (the curvature and torsion of the force lines of the magnetic field and the field complementary to it) and magnetic (|B|, |{nabla}{Phi}|, b {center_dot} ({nabla} x b), and the local shear s) quantities in currentless magnetic configurations comprising a system of equilibrium nested magnetic surfaces, including those with several magnetic axes, is derived. Possible applications of these relationships are discussed.

  7. Discovery of magnetic fields in CPNs

    E-Print Network [OSTI]

    S. Jordan; K. Werner; S. J. O'Toole

    2004-10-21T23:59:59.000Z

    For the first time we have directly detected magnetic fields in central stars of planetary nebulae by means of spectro-polarimetry with FORS1 at the VLT. In all four objects of our sample we found kilogauss magnetic fields, in NGC 1360 and LSS1362 with very high significance, while in Abell36 and EGB5 the existence of a magnetic field is probable but with less certainty. This discovery supports the hypothesis that the non-spherical symmetry of most planetary nebulae is caused by magnetic fields in AGB stars. Our high discovery rate demands mechanisms to prevent full conservation of magnetic flux during the transition to white dwarfs.

  8. Baryon onset in a magnetic field

    E-Print Network [OSTI]

    Alexander Haber; Florian Preis; Andreas Schmitt

    2014-12-19T23:59:59.000Z

    The critical baryon chemical potential for the onset of nuclear matter is a function of the vacuum mass and the binding energy. Both quantities are affected by an external magnetic field. We show within two relativistic mean-field models - including magnetic catalysis, but omitting the anomalous magnetic moment - that a magnetic field increases both the vacuum mass and the binding energy. For sufficiently large magnetic fields, the effect on the vacuum mass dominates and as a result the critical baryon chemical potential is increased.

  9. Magnetic field-line lengths inside interplanetary magnetic flux ropes

    E-Print Network [OSTI]

    Hu, Qiang; Krucker, Sam

    2015-01-01T23:59:59.000Z

    We report on the detailed and systematic study of field-line twist and length distributions within magnetic flux ropes embedded in Interplanetary Coronal Mass Ejections (ICMEs). The Grad-Shafranov reconstruction method is utilized together with a constant-twist nonlinear force-free (Gold-Hoyle) flux rope model to reveal the close relation between the field-line twist and length in cylindrical flux ropes, based on in-situ Wind spacecraft measurements. We show that the field-line twist distributions within interplanetary flux ropes are inconsistent with the Lundquist model. In particular we utilize the unique measurements of magnetic field-line lengths within selected ICME events as provided by Kahler et al. (2011) based on energetic electron burst observations at 1 AU and the associated type III radio emissions detected by the Wind spacecraft. These direct measurements are compared with our model calculations to help assess the flux-rope interpretation of the embedded magnetic structures. By using the differen...

  10. Magnetic switch for reactor control rod

    DOE Patents [OSTI]

    Germer, John H. (San Jose, CA)

    1986-01-01T23:59:59.000Z

    A magnetic reed switch assembly for activating an electromagnetic grapple utilized to hold a control rod in position above a reactor core. In normal operation the magnetic field of a permanent magnet is short-circuited by a magnetic shunt, diverting the magnetic field away from the reed switch. The magnetic shunt is made of a material having a Curie-point at the desired release temperature. Above that temperature the material loses its ferromagnetic properties, and the magnetic path is diverted to the reed switch which closes and short-circuits the control circuit for the control rod electromagnetic grapple which allows the control rod to drop into the reactor core for controlling the reactivity of the core.

  11. Nonuniform radiation damage in permanent magnet quadrupoles

    SciTech Connect (OSTI)

    Danly, C. R.; Merrill, F. E.; Barlow, D.; Mariam, F. G. [Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)

    2014-08-15T23:59:59.000Z

    We present data that indicate nonuniform magnetization loss due to radiation damage in neodymium-iron-boron Halbach-style permanent magnet quadrupoles. The proton radiography (pRad) facility at Los Alamos uses permanent-magnet quadrupoles for magnifying lenses, and a system recently commissioned at GSI-Darmsdadt uses permanent magnets for its primary lenses. Large fluences of spallation neutrons can be produced in close proximity to these magnets when the proton beam is, intentionally or unintentionally, directed into the tungsten beam collimators; imaging experiments at LANL’s pRad have shown image degradation with these magnetic lenses at proton beam doses lower than those expected to cause damage through radiation-induced reduction of the quadrupole strength alone. We have observed preferential degradation in portions of the permanent magnet quadrupole where the field intensity is highest, resulting in increased high-order multipole components.

  12. SUPERCONDUCTING MAGNET NEEDS FOR THE ILC.

    SciTech Connect (OSTI)

    PARKER,B.; TOMPKINS, J.C.; KASHIKHIN, VI.; PALMER, M.A.; CLARKE, J.A.

    2007-06-25T23:59:59.000Z

    The ILC Reference Design Report was completed early in February 2007. The Magnet Systems Group was formed to translate magnetic field requirements into magnet designs and cost estimates for the Reference Design. As presently configured, the lLC will have more than 13,000 magnetic elements of which more than 2300 will be based on superconducting technology. This paper will describe the major superconducting magnet needs for the ILC as presently determined by the Area Systems Groups, responsible for beam line design, working with the Magnet Systems Group. The superconducting magnet components include Main Linac quadrupoles, Positron Source undulators, Damping Ring wigglers, a complex array of Final Focus superconducting elements in the Beam Delivery System, and large superconducting solenoids in the e{sup +} and e{sup -} Sources, and the Ring to Main Linac lines.

  13. Superconducting magnet needs for the ILC

    SciTech Connect (OSTI)

    Tompkins, J.C.; Kashikhin, Vl.; /Fermilab; Parker, B.; /Brookhaven; Palmer, M.A. /; Clarke, J.A.; /Daresbury

    2007-06-01T23:59:59.000Z

    The ILC Reference Design Report was completed early in February 2007. The Magnet Systems Group was formed to translate magnetic field requirements into magnet designs and cost estimates for the Reference Design. As presently configured, the ILC will have more than 13,000 magnetic elements of which more than 2300 will be based on superconducting technology. This paper will describe the major superconducting magnet needs for the ILC as presently determined by the Area Systems Groups, responsible for beam line design, working with the Magnet Systems Group. The superconducting magnet components include Main Linac quadrupoles, Positron Source undulators, Damping Ring wigglers, a complex array of Final Focus superconducting elements in the Beam Delivery System, and large superconducting solenoids in the e{sup +} and e{sup -} Sources, and the Ring to Main Linac lines.

  14. Plume detachment from a magnetic nozzle

    SciTech Connect (OSTI)

    Deline, Christopher A. [University of Michigan, Ann Arbor, Michigan 48109 (United States); Bengtson, Roger D.; Breizman, Boris N.; Tushentsov, Mikhail R. [Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States); Jones, Jonathan E.; Chavers, D. Greg; Dobson, Chris C. [Marshall Space Flight Center, Huntsville, Alabama 35805 (United States); Schuettpelz, Branwen M. [University of Alabama at Huntsville, Huntsville, Alabama 35899 (United States)

    2009-03-15T23:59:59.000Z

    High-powered electric propulsion thrusters utilizing a magnetized plasma require that plasma exhaust detach from the applied magnetic field in order to produce thrust. This paper presents experimental results demonstrating that a sufficiently energetic and flowing plasma can indeed detach from a magnetic nozzle. Microwave interferometer and probe measurements provide plume density, electron temperature, and ion flux measurements in the nozzle region. Measurements of ion flux show a low-beta plasma plume which follows applied magnetic field lines until the plasma kinetic pressure reaches the magnetic pressure and a high-beta plume expanding ballistically afterward. Several magnetic configurations were tested including a reversed field nozzle configuration. Despite the dramatic change in magnetic field profile, the reversed field configuration yielded little measurable change in plume trajectory, demonstrating the plume is detached. Numerical simulations yield density profiles in agreement with the experimental results.

  15. Japanese magnetic confinement fusion research

    SciTech Connect (OSTI)

    Davidson, R.C.; Abdou, M.A.; Berry, L.A.; Horton, C.W.; Lyon, J.F.; Rutherford, P.H.

    1990-01-01T23:59:59.000Z

    Six U.S. scientists surveyed and assessed Japanese research and development in magnetic fusion. The technical accomplishments from the early 1980s through June 1989 are reviewed, and the Japanese capabilities and outlook for future contributions are assessed. Detailed evaluations are provided in the areas of basic and applied plasma physics, tokamak confinement, alternate confinement approaches, plasma technology, and fusion nuclear technology and materials.

  16. Modelling of bulk superconductor magnetization

    E-Print Network [OSTI]

    Ainslie, M. D.; Fujishiro, H.

    2015-03-30T23:59:59.000Z

    synchronous motor. It may also be possible to use superconducting materials of different Tcs and a dual cooling system to develop an in-situ FC magnetization process for YBCO bulk plates using the superconducting stator coils of an electric machine... . Furthermore, the relative ease of fabrication of MgB2 materials, as well as their long coherence length [10], lower anisotropy and strongly linked supercurrent flow in untextured polycrystalline samples [11,12], has enabled a number of different processing...

  17. Magnetic Bottles on Riemann Surfaces

    E-Print Network [OSTI]

    Gavriel Segre

    2011-01-17T23:59:59.000Z

    Yves Colin de Verdiere's quantization formalism of magnetic bottles on Riemann surfaces of non null genus is shown to be affected, owing to the Homotopy Superselection Rule, by the phenomenon of the existence of multiple inequivalent quantizations mathematically analogous to the phenomenon of the existence of multiple inequivalent prequantizations of a multiply-connected symplectic manifold in the framework of Souriau-Kostant's Geometric Quantization.

  18. Thermodynamic properties of a magnetically modulated graphene

    E-Print Network [OSTI]

    SK Firoz Islam; Naveen K. Singh; Tarun Kanti Ghosh

    2011-09-12T23:59:59.000Z

    The effect of magnetic modulation on thermodynamic properties of a graphene monolayer in presence of a constant perpendicular magnetic field is reported here. One-dimensional spatial electric or magnetic modulation lifts the degeneracy of the Landau levels and converts into bands and their band width oscillates with magnetic field leading to Weiss-type oscillation in the thermodynamic properties. The effect of magnetic modulation on thermodynamic properties of a graphene sheet is studied and then compared with electrically modulated graphene and magnetically modulated conventional two-dimensional electron gas (2DEG). We observe Weiss-type and de Haas-van Alphen (dHvA) oscillations at low and high magnetic field, respectively. There is a definite phase difference in Weiss-type oscillations in thermodynamic quantities of magnetically modulated graphene in compare to electrically modulated graphene. On the other hand, the phase remains same and amplitude of the oscillation is large when compared with the magnetically modulated 2DEG. Explicit asymptotic expressions of density of states and the Helmholtz free energy are provided to understand the phase and amplitude of the Weiss-type oscillations qualitatively. We also study thermodynamic properties when both electric and magnetic modulations are present. The Weiss-type oscillations still exist when the modulations are out-of-phase.

  19. Magnetic switch for reactor control rod

    SciTech Connect (OSTI)

    Germer, J.H.

    1986-04-15T23:59:59.000Z

    This patent describes a control rod system for a nuclear reactor utilizing an electromagnetic grapple mechanism for holding and releasing a control rod, the improvement comprising a magnetic reed switch assembly having a Curie-point magnetic shunt and responsive to reactor coolant temperature for short circuiting the electromagnetic grapple mechanism causing release of the control rod when the coolant temperature reaches the Curie-point of the magnetic shunt. The magnetic reed switch assembly includes a: a permanent magnet, a pair of magnetic pole pieces located at and in contact with opposite ends of the permanent magnet, the Curie-point magnetic shunt being positioned adjacent the permanent magnet and in contact with the pair of magnetic pole pieces, and a reed switch positioned intermediate the pole pieces and provided with a pair of ferromagnetic reeds, a nonmagnetic enclosure around the reeds, a first of the reeds being secured at one end to a first of the pair of pole pieces, a second of the reeds having one end extending into and secured to a hollow member positioned in and extending through a second of the pair of pole pieces, the one end of the second of the reeds secured to a condector adapted to be connected to the electromagnetic grapple mechanism.

  20. Formation of magnetic discontinuities through viscous relaxation

    SciTech Connect (OSTI)

    Kumar, Sanjay; Bhattacharyya, R. [Udaipur Solar Observatory, Physical Research Laboratory, Dewali, Bari Road, Udaipur-313001 (India); Smolarkiewicz, P. K. [European Centre for Medium-Range Weather Forecasts, Reading RG2 9AX (United Kingdom)

    2014-05-15T23:59:59.000Z

    According to Parker's magnetostatic theorem, tangential discontinuities in magnetic field, or current sheets (CSs), are generally unavoidable in an equilibrium magnetofluid with infinite electrical conductivity and complex magnetic topology. These CSs are due to a failure of a magnetic field in achieving force-balance everywhere and preserving its topology while remaining in a spatially continuous state. A recent work [Kumar, Bhattacharyya, and Smolarkiewicz, Phys. Plasmas 20, 112903 (2013)] demonstrated this CS formation utilizing numerical simulations in terms of the vector magnetic field. The magnetohydrodynamic simulations presented here complement the above work by demonstrating CS formation by employing a novel approach of describing the magnetofluid evolution in terms of magnetic flux surfaces instead of the vector magnetic field. The magnetic flux surfaces being the possible sites on which CSs develop, this approach provides a direct visualization of the CS formation, helpful in understanding the governing dynamics. The simulations confirm development of tangential discontinuities through a favorable contortion of magnetic flux surfaces, as the magnetofluid undergoes a topology-preserving viscous relaxation from an initial non-equilibrium state with twisted magnetic field. A crucial finding of this work is in its demonstration of CS formation at spatial locations away from the magnetic nulls.

  1. Thermal modeling of the Tevatron magnet system

    SciTech Connect (OSTI)

    Jay C. Theilacker; Arkadiy L. Klebaner

    2004-07-20T23:59:59.000Z

    Operation of the Tevatron at lower temperatures, for the purpose of allowing higher energies, has resulted in a renewed interest in thermal modeling of the magnet strings. Static heat load and AC loses in the superconducting coils are initially transported through subcooled liquid helium. Heat exchange between the subcooled liquid and a counter flowing two-phase stream transfers the load to the latent heat. Stratification of the two-phase helium stream has resulted in considerably less heat exchange compared to the original design. Spool pieces have virtually no heat transfer to the two-phase resulting in a ''warm'' dipole just downstream. A model of the magnet string thermal behavior has been developed. The model has been used to identify temperature profiles within magnet strings. The temperature profiles are being used in conjunction with initial magnet quench performance data to predict the location of quench limiting magnets within the Tevatron. During thermal cycles of magnet strings, the model is being used to ''shuffle'' magnets within the magnet string in order to better match the magnets quench performance with its actual predicted temperature. The motivation for this analysis is to raise the operating energy of the Tevatron using a minimal number of magnets from the spares pool.

  2. What Happened with Spectrometer Magnet 2B

    SciTech Connect (OSTI)

    Green, Michael A

    2010-05-27T23:59:59.000Z

    The spectrometer solenoid is supposed to be the first magnets installed in MICE [1]-[4]. This report described what happened during the test of the MICE spectrometer solenoid 2B. First, the report describes the temperatures in the magnet, the cooler top plate and the shield during the run where the magnet quenched at 258 A. During this quench, a lead between the bottom of the HTS leads and the diode bank burned out causing the magnet to quench. Second, three methods for measuring the net heat flow into the cold mass are described. Third, there is a discussion of possible resistive heating in the HTS leads between liquid helium temperature and the copper plate, which is at about 50 K. Fourth, there is a discussion of the measured first stage heat loads in the magnet, when there is no current in the magnet. The first stage heat load calculations are based on knowing the first stage temperatures of the three two-stage pulse tube coolers and the single stage GM cooler. Fifth, the estimated heat load to the first stage when the magnet has current in it is discussed. Sixth, there is a comparison of the stage 1 heat loads in magnet 1A [5], magnet 2A [6], and magnet 2B [7]. Finally there is a discussion of recommended changes for improving the spectrometer solenoids so that the coolers can keep them cold.

  3. Electronic Structure and Magnetism in Diluted Magnetic Semiconductors

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField Campaign:INEAWater UseC Supports -Electronic Structure and Magnetism in

  4. Electronic Structure and Magnetism in Diluted Magnetic Semiconductors

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField Campaign:INEAWater UseC Supports -Electronic Structure and Magnetism

  5. Magnetic Filtration Process, Magnetic Filtering Material, and Method of

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9November 6, InaprilU . SMagellanForming Magnetic

  6. Thermomagnetic burn control for magnetic fusion reactor

    DOE Patents [OSTI]

    Rawls, J.M.; Peuron, A.U.

    1980-07-01T23:59:59.000Z

    Apparatus is provided for controlling the plasma energy production rate of a magnetic-confinement fusion reactor, by controlling the magnetic field ripple. The apparatus includes a group of shield sectors formed of ferromagnetic material which has a temperature-dependent saturation magnetization, with each shield lying between the plasma and a toroidal field coil. A mechanism for controlling the temperature of the magnetic shields, as by controlling the flow of cooling water therethrough, thereby controls the saturation magnetization of the shields and therefore the amount of ripple in the magnetic field that confines the plasma, to thereby control the amount of heat loss from the plasma. This heat loss in turn determines the plasma state and thus the rate of energy production.

  7. Relativistic Shocks: Particle Acceleration and Magnetization

    E-Print Network [OSTI]

    Sironi, Lorenzo; Lemoine, Martin

    2015-01-01T23:59:59.000Z

    We review the physics of relativistic shocks, which are often invoked as the sources of non-thermal particles in pulsar wind nebulae (PWNe), gamma-ray bursts (GRBs), and active galactic nuclei (AGN) jets, and as possible sources of ultra-high energy cosmic-rays. We focus on particle acceleration and magnetic field generation, and describe the recent progress in the field driven by theory advances and by the rapid development of particle-in-cell (PIC) simulations. In weakly magnetized or quasi parallel-shocks (where the magnetic field is nearly aligned with the flow), particle acceleration is efficient. The accelerated particles stream ahead of the shock, where they generate strong magnetic waves which in turn scatter the particles back and forth across the shock, mediating their acceleration. In contrast, in strongly magnetized quasi-perpendicular shocks, the efficiencies of both particle acceleration and magnetic field generation are suppressed. Particle acceleration, when efficient, modifies the turbulence ...

  8. HTS High Gradient Magnetic Separation system

    SciTech Connect (OSTI)

    Daugherty, M.A.; Coulter, J.Y.; Hults, W.L. [and others

    1996-09-01T23:59:59.000Z

    We report on the assembly, characterization and operation of a high temperature superconducting (HTS) magnetic separator. The magnet is made of 624 m of Silver/BSCCO superconducting wire and has overall dimensions of 18 cm OD, 15.5 cm height and 5 cm ID. The HTS current leads are designed to operate with the warm end at 75 K and the cold end cooled by a two stage Gifford-McMahon cryocooler. The upper stage of the cryocooler cools the thermal shield and two heat pipe thermal intercepts. The lower stage of the cryocooler cools the HTS magnet and the bottom end of the HTS current leads. The HTS magnet was initially characterized in liquid cryogens. We report on the current- voltage (I-V) characteristics of the HTS magnet at temperatures ranging from 15 to 40 K. At 40 K the magnet can generate a central field of 2.0 T at a current of 120 A.

  9. Thermomagnetic burn control for magnetic fusion reactor

    DOE Patents [OSTI]

    Rawls, John M. (Del Mar, CA); Peuron, Unto A. (Solana Beach, CA)

    1982-01-01T23:59:59.000Z

    Apparatus is provided for controlling the plasma energy production rate of a magnetic-confinement fusion reactor, by controlling the magnetic field ripple. The apparatus includes a group of shield sectors (30a, 30b, etc.) formed of ferromagnetic material which has a temperature-dependent saturation magnetization, with each shield lying between the plasma (12) and a toroidal field coil (18). A mechanism (60) for controlling the temperature of the magnetic shields, as by controlling the flow of cooling water therethrough, thereby controls the saturation magnetization of the shields and therefore the amount of ripple in the magnetic field that confines the plasma, to thereby control the amount of heat loss from the plasma. This heat loss in turn determines the plasma state and thus the rate of energy production.

  10. Self-assembled magnetic surface swimmers.

    SciTech Connect (OSTI)

    Snezhko, A.; Belkin, M.; Aranson, I. S.; Kwok, W.-K.; Materials Science Division; Illinois Inst. of Tech.

    2009-03-20T23:59:59.000Z

    We report studies of novel self-assembled magnetic surface swimmers (magnetic snakes) formed from a dispersion of magnetic microparticles at a liquid-air interface and energized by an alternating magnetic field. We show that under certain conditions the snakes spontaneously break the symmetry of surface flows and turn into self-propelled objects. Parameters of the driving magnetic field tune the propulsion velocity of these snakelike swimmers. We find that the symmetry of the surface flows can also be broken in a controlled fashion by attaching a large bead to a magnetic snake (bead-snake hybrid), transforming it into a self-locomoting entity. The observed phenomena have been successfully described by a phenomenological model based on the amplitude equation for surface waves coupled to a large-scale hydrodynamic mean flow equation.

  11. Magnetic structure of Coronal Mass Ejections

    E-Print Network [OSTI]

    Lyutikov, Maxim

    2012-01-01T23:59:59.000Z

    We present several models of the magnetic structure of solar coronal mass ejections (CMEs). First, we model CMEs as expanding force-free magnetic structures. While keeping the internal magnetic field structure of the stationary solutions, expansion leads to complicated internal velocities and rotation, while the field structures remain force-free. Second, expansion of a CME can drive resistive dissipation within the CME changing the ionization states of different ions. We fit in situ measurements of ion charge states to the resistive spheromak solutions. Finally, we consider magnetic field structures of fully confined stable magnetic clouds containing both toroidal and poloidal magnetic fields and having no surface current sheets. Expansion of such clouds may lead to sudden onset of reconnection events.

  12. Geometrically induced magnetic catalysis and critical dimensions

    E-Print Network [OSTI]

    Antonino Flachi; Kenji Fukushima; Vincenzo Vitagliano

    2015-04-27T23:59:59.000Z

    We discuss the combined effect of magnetic fields and geometry in interacting fermionic systems. At leading order in the heat-kernel expansion, the infrared singularity (that in flat space leads to the magnetic catalysis) is regulated by the chiral gap effect, and the catalysis is deactivated by the effect of the scalar curvature. We discover that an infrared singularity is found in higher-order terms that mix the magnetic field with curvature, and these lead to a novel form of geometrically induced magnetic catalysis. The dynamical mass squared is then modified not only due to the chiral gap effect by an amount proportional to the curvature, but also by a magnetic shift $\\propto (4-D)eB$, where $D$ represents the number of space-time dimensions. We argue that $D=4$ is a critical dimension across which the behavior of the magnetic shift changes qualitatively.

  13. Planar superconductor/ferromagnet hybrids: Anisotropy of resistivity induced by magnetic templates

    E-Print Network [OSTI]

    Moshchalkov, Victor V.

    of vortices by various magnetic textures: periodic arrays of magnetic dots9,10 or irregular magnetic bubble

  14. A Synergy of Novel Experiments, Materials Science, Fundamental Physics, and Superconducting Magnets

    E-Print Network [OSTI]

    Godeke, Arno

    2007-01-01T23:59:59.000Z

    Fundamental Physics Superconducting Magnets Yields: Accuraterecord setting superconducting magnet systems ITER, NMRScience, Fundamental Physics, and Superconducting Magnets

  15. Magnetism and superconductivi[t]y in Pr-based filled skutterudite arsenides

    E-Print Network [OSTI]

    Sayles, Todd Allen

    2008-01-01T23:59:59.000Z

    1.3 Magnetism . . . . .1.3.3 Itinerant Magnetism . . . . . . . . . . .3.3 Magnetism . . . . . . . . . . . . . . . . . . . . . 3.4

  16. Inversion of marine magnetic anomalies by deconvolution

    E-Print Network [OSTI]

    Harry, Dennis Lee

    1983-01-01T23:59:59.000Z

    -Chairmen of Advisory Committee: Dr. Richard L. Carlson Dr. Phillip D. Rabinowitz Marine magnetic anomalies can be expressed as a convolution between the equivalent magnetic line source in the oceanic crust and a transfer function. The transfer function contains..., with the resulting anomaly still exhibiting sharp reversals. This is compatible with the results of magnetic studies of ophiolites and dredged oceanic rocks, which indicate that a smoothly varying source is more probable than a block model for the generation...

  17. Magnetic anomalies northeast of Shatsky Plateau

    E-Print Network [OSTI]

    Risch, David Lawrence

    1982-01-01T23:59:59.000Z

    MAGNETIC ANOMALIES NORTHEAST OF SHATSKY PLATEAU A Thesis by DAVID LAWRENCE RISCH Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May 1982 Major Subject...: Oceanography MAGNETIC ANOMALIES NORTHEAST OF SHATSKY PLATEAU A Thesis by DAVID LAWRENCE RISCH Approved as to style and content by: C rman Committee Member Member Head of Department May 198Z ABSTRACT Magnetic Anomalies Northeast of Shatsky Plateau...

  18. Permanent magnet edge-field quadrupole

    DOE Patents [OSTI]

    Tatchyn, Roman O. (Mountain View, CA)

    1997-01-01T23:59:59.000Z

    Planar permanent magnet edge-field quadrupoles for use in particle accelerating machines and in insertion devices designed to generate spontaneous or coherent radiation from moving charged particles are disclosed. The invention comprises four magnetized rectangular pieces of permanent magnet material with substantially similar dimensions arranged into two planar arrays situated to generate a field with a substantially dominant quadrupole component in regions close to the device axis.

  19. Magnetism and superconductivity in quark matter

    E-Print Network [OSTI]

    T. Tatsumi; E. Nakano; K. Nawa

    2005-06-01T23:59:59.000Z

    Magnetic properties of quark matter and its relation to the microscopic origin of the magnetic field observed in compact stars are studied. Spontaneous spin polarization appears in high-density region due to the Fock exchange term, which may provide a scenario for the behaviors of magnetars. On the other hand, quark matter becomes unstable to form spin density wave in the moderate density region, where restoration of chiral symmetry plays an important role. Coexistence of magnetism and color superconductivity is also discussed.

  20. Microwave magnetic dynamics in highly conducting magnetic nanostructures

    SciTech Connect (OSTI)

    Kostylev, M.; Ivanov, E.; Samarin, S. [School of Physics M013, The University of Western Australia, Crawley, WA 6009 (Australia); Ding, J.; Adeyeye, A. O. [Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576 (Singapore)

    2014-05-07T23:59:59.000Z

    We performed low-noise broadband microstrip ferromagnetic resonance (FMR) measurements of the resonant modes of an array of metallic ferromagnetic nanostripes. In addition to a strong signal of the fundamental mode, we observed up to five weak-amplitude peaks in the field-resolved FMR traces, depending on the frequency. These higher-order absorption peaks have been theoretically identified as due to resonant excitation of odd and even standing spin waves across the direction of confinement in array plane (i.e., across the stripe width). The theory we developed suggests that the odd modes become excited in the spatially uniform microwave field of the FMR setup due to the large conductivity of metals. This promotes excitation of large-amplitude eddy currents in the sample by the incident microwave magnetic field and ultimately results in excitation of these modes. Following this theory, we found that the eddy current contribution is present only for patterned materials and when the microwave magnetic field is incident on one surface of sample surface, as it is in the case of a microstrip FMR.

  1. Measuring and shimming the magnetic field of a 4 Tesla MRI magnet

    E-Print Network [OSTI]

    Kyriazis, Georgios

    1993-01-01T23:59:59.000Z

    The Biomedical Magnetic Resonance Laboratory (BMRL) of the University of Illinois at Urbana-Champaign (UIUC) has ordered from the Texas Accelerator Center (TAC) a superconducting, self-shielded, solenoidal magnet with a maximum field of 4 Tesla...

  2. Magnetic field-induced phase transformation & power harvesting capabilities in magnetic shape memory alloys

    E-Print Network [OSTI]

    Basaran, Burak

    2011-02-22T23:59:59.000Z

    Magnetic Shape Memory Alloys (MSMAs) combine shape-change/deformationrecovery abilities of heat driven conventional shape memory alloys (SMA) and magnetic field driven magnetostrictives through martensitic transformation. They are promising...

  3. Exchange-Spring Magnets: Nanocomposite Exchange-Spring Magnets for Motor and Generator Applications

    SciTech Connect (OSTI)

    None

    2012-01-01T23:59:59.000Z

    REACT Project: ANL will develop a cost-effective exchange-spring magnet to use in the electric motors of wind generators and EVs that uses no rare earth materials. This ANL exchange-spring magnet combines a hard magnetic outer shell with a soft magnetic inner core—coupling these together increases the performance (energy density and operating temperature). The hard and soft magnet composite particles would be created at the molecular level, followed by consolidation in a magnetic field. This process allows the particles to be oriented to maximize the magnetic properties of low-cost and abundant metals, eliminating the need for expensive imported rare earths. The ultimate goal of this project is to demonstrate this new type of magnet in a prototype electric motor.

  4. Understanding magnetic field reversal mechanisms in mesoscopic magnetic multilayer ring structures

    E-Print Network [OSTI]

    Ng, Bryan

    2008-01-01T23:59:59.000Z

    Patterned pseudo spin-valve rings show great promise for device applications due to their non-volatility and variety of stable magnetic states. However, the magnetic reversal of these elements under an applied field is ...

  5. Integral magnetic ignition pickup trigger

    SciTech Connect (OSTI)

    King, R.

    1992-10-27T23:59:59.000Z

    This patent describes a trigger system for the ignition system of an internal combustion engine having a crankcase with a rotatable crankshaft therein, and a flywheel on one end of the crankcase connected to an end of the crankshaft. It comprises: a nonferromagnetic disk-shaped hub for connection to the crankshaft and rotatable therewith on the end opposite the flywheel; and a stationary sensor mounted adjacent the hub for detecting impulses from the magnetically responsive elements as the hub rotates and utilizing the impulses to trigger the ignition system.

  6. Large Magnetization at Carbon Surfaces

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9 5 - -/e),,sand CERNLandLarge Magnetization at

  7. Large Magnetization at Carbon Surfaces

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9 5 - -/e),,sand CERNLandLarge Magnetization

  8. Lensless Imaging of Magnetic Nanostructures

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9 5 -ofLearningLensless Imaging of Magnetic

  9. Lensless Imaging of Magnetic Nanostructures

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9 5 -ofLearningLensless Imaging of MagneticLensless

  10. Ground Magnetics | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual SiteofEvaluating AGeothermal/ExplorationGoods | OpenInformationMagnetics Jump to:

  11. Direct Imaging of Asymmetric Magnetization Reversal

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

    new information storage and sensing devices. There are two basic energies involved in the manipulation and control of the magnetic properties of materials. Exchange controls...

  12. Mixing zones in magnetized differentially rotating stars

    E-Print Network [OSTI]

    V. Urpin

    2005-09-29T23:59:59.000Z

    We study the secular instability of magnetized differentially rotating radiative zones taking account of viscosity and magnetic and thermal diffusivities. The considered instability generalizes the well-known Goldreich-Schubert-Fricke instability for the case of a sufficiently strong magnetic field. In magnetized stars, instability can lead to a formation of non-spherical unstable zones where weak turbulence mixes the material between the surface and interiors. Such unstable zones can manifest themselves by a non-spherical distribution of abundance anormalies on the stellar surface.

  13. External-field-free magnetic biosensor

    SciTech Connect (OSTI)

    Li, Yuanpeng; Wang, Yi; Klein, Todd; Wang, Jian-Ping, E-mail: jpwang@umn.edu [Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2014-03-24T23:59:59.000Z

    In this paper, we report a magnetic nanoparticle (MNP) detection scheme without the presence of any external magnetic field. The proposed magnetic sensor uses a patterned groove structure within the sensor so that no external magnetic field is needed to magnetize the MNPs. An example is given based on a giant magnetoresistance (GMR) sensing device with a spin valve structure. For this structure, the detection of MNPs located inside the groove and near the free layer is demonstrated under no external magnetic field. Micromagnetic simulations are performed to calculate the signal to noise level of this detection scheme. A maximum signal to noise ratio (SNR) of 18.6?dB from one iron oxide magnetic nanoparticle with 8?nm radius is achieved. As proof of concept, this external-field-free GMR sensor with groove structure of 200?nm?×?200?nm is fabricated using a photo and an electron beam integrated lithography process. Using this sensor, the feasibility demonstration of the detection SNR of 9.3?dB is achieved for 30??l magnetic nanoparticles suspension (30?nm iron oxide particles, 1?mg/ml). This proposed external-field-free sensor structure is not limited to GMR devices and could be applicable to other magnetic biosensing devices.

  14. Interaction of Ferromagnetic and Superconducting Permanent Magnets...

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

    permanent magnet track, was put into operation. A vehicle for 2 passengers, equipped with linear drive propulsion, a noncontact energy supply, a second braking system, and various...

  15. Effect of Minimal lengths on Electron Magnetism

    E-Print Network [OSTI]

    Khireddine Nouicer

    2007-07-13T23:59:59.000Z

    We study the magnetic properties of electron in a constant magnetic field and confined by a isotropic two dimensional harmonic oscillator on a space where the coordinates and momenta operators obey generalized commutation relations leading to the appearance of a minimal length. Using the momentum space representation we determine exactly the energy eigenvalues and eigenfunctions. We prove that the usual degeneracy of Landau levels is removed by the presence of the minimal length in the limits of weak and strong magnetic field.The thermodynamical properties of the system, at high temperature, are also investigated showing a new magnetic behavior in terms of the minimal length.

  16. Magnetic fields in anisotropic relativistic stars

    E-Print Network [OSTI]

    Vladimir Folomeev; Vladimir Dzhunushaliev

    2015-02-28T23:59:59.000Z

    Relativistic, spherically symmetric configurations consisting of a gravitating magnetized anisotropic fluid are studied. For such configurations, we obtain static equilibrium solutions with an axisymmetric, poloidal magnetic field produced by toroidal electric currents. The presence of such a field results in small deviations of the shape of the configuration from spherical symmetry. This in turn leads to the modification of an equation for the current and correspondingly to changes in the structure of the internal magnetic field for the systems supported by the anisotropic fluid, in contrast to the case of an isotropic fluid, where such deviations do not affect the magnetic field.

  17. Revealing Cosmic Magnetism with Radio Polarimetry

    E-Print Network [OSTI]

    Bryan M. Gaensler

    2007-12-18T23:59:59.000Z

    While gravitation sustains the on-going evolution of the cosmos, it is magnetism that breaks gravity's symmetry and that provides the pathway to the non-thermal Universe. By enabling processes such as anisotropic pressure support, particle acceleration, and jet collimation, magnetism has for billions of years regulated the feedback vital for returning matter to the interstellar and intergalactic medium. After reviewing recent results that demonstrate the unique view of magnetic fields provided by radio astronomy, I explain how the Square Kilometre Array will provide data that will reveal what cosmic magnets look like, how they formed, and what role they have played in the evolving Universe.

  18. The Butterfly Effect on Magnetic Vortices

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

    A. Vogel, J.-I. Hong, G. Meier, and P. Fischer, "Stochastic formation of magnetic vortex structures in asymmetric disks triggered by chaotic dynamics," Nature Communications 5,...

  19. Induced Magnetism in Color-Superconducting Media

    E-Print Network [OSTI]

    Efrain J. Ferrer

    2010-01-22T23:59:59.000Z

    The dense core of compact stars is the natural medium for the realization of color superconductivity. A common characteristic of such astrophysical objects is their strong magnetic fields, especially those of the so called magnetars. In this talk, I discuss how a color superconducting core can generate or/and enhance the stellar magnetic field independently of a magnetohydrodynamic dynamo mechanism. The magnetic field generator is in this case a gluonic current which circulates to stabilize the color superconductor in the presence of a strong magnetic field or under the pairing stress produced in the medium by the neutrality and $\\beta$-equilibrium constraints.

  20. Quantitative Modeling of High Temperature Magnetization Dynamics

    SciTech Connect (OSTI)

    Zhang, Shufeng

    2009-03-01T23:59:59.000Z

    Final Technical Report Project title: Quantitative Modeling of High Temperature Magnetization Dynamics DOE/Office of Science Program Manager Contact: Dr. James Davenport

  1. Apparatus and method for magnetically processing a specimen

    DOE Patents [OSTI]

    Ludtka, Gerard M; Ludtka, Gail M; Wilgen, John B; Kisner, Roger A; Jaramillo, Roger A

    2013-09-03T23:59:59.000Z

    An apparatus for magnetically processing a specimen that couples high field strength magnetic fields with the magnetocaloric effect includes a high field strength magnet capable of generating a magnetic field of at least 1 Tesla and a magnetocaloric insert disposed within a bore of the high field strength magnet. A method for magnetically processing a specimen includes positioning a specimen adjacent to a magnetocaloric insert within a bore of a magnet and applying a high field strength magnetic field of at least 1 Tesla to the specimen and to the magnetocaloric insert. The temperature of the specimen changes during the application of the high field strength magnetic field due to the magnetocaloric effect.

  2. Magnetism at spinel thin film interfaces probed through soft x-ray spectroscopy techniques

    E-Print Network [OSTI]

    Chopdekar, R.V.

    2010-01-01T23:59:59.000Z

    Magnetism at spinel thin ?lm interfaces probed through softachievable in bulk form. Magnetism at the interface regionand the origin of the magnetism from multiple magnetic

  3. Gigahertz Non-Volatile Voltage Tuned Magnetic Film Inductors using a Ni/NiFe Core

    E-Print Network [OSTI]

    Lewis, Mark Dylan

    2012-01-01T23:59:59.000Z

    energy harvesting, magnetic recording devices, and electric and magnetic field tunable microwaveenergy harvesting, magnetic recording devices, and electric and magnetic field tunable microwave

  4. amino-functionalized magnetic nano-adsorbent: Topics by E-print...

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

    to have a noncollinear magnetic structure. 1.1 Related Studies 1 unknown authors 8 Superconducting Magnet Division Magnet Note Physics Websites Summary: Magnet Title: Engineering...

  5. Nuclear magnetic absorption line widths in weak magnetic fields with a Robinson oscillator

    E-Print Network [OSTI]

    Flugum, Timothy Lee

    1987-01-01T23:59:59.000Z

    NUCLEAR MAGNETIC ABSORPTION LINE WIDTHS IN WEAK MAGNETIC FIELDS WITH A ROBINSON OSCILLATOR A Thesis by TIMOTHY LEE FLUGUM Subnntted to the Graduate College of Texas ARM University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE August 19SI Major Subject: Physics NUCLEAR MAGNETIC ABSORPTION LINE WIDTHS IN WEAK MAGNETIC FIELDS WITH A ROBINSON OSCILLATOR A Thesis TIMOTHY LEE FLUGUM Approved as to style and content by: Nelson M. Duller (Chairman...

  6. Development of magnetic separation methods of analysis: magnetic field flow fractionation

    E-Print Network [OSTI]

    Garcia-Ramirez, Jaime

    1980-01-01T23:59:59.000Z

    DEVELOPMENT OF MAGNETIC SEPARATION METHODS OF ANALYSIS: MAGNETIC FIELD FLOW FRACTIONATION A Thesis by JAIME GARCIA-RAMIREZ Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE August 1980 Major Subject: Chemistry DEVELOPMENT OF MAGNETIC SEPARATION METHODS OF ANALYSIS: MAGNETIC FIELD FLOW FRACTIONATION A Thesis by JAIME GARCIA-RAMIREZ Approved as to style and content by: (Chairman of Committee) 1...

  7. Method for obtaining large levitation pressure in superconducting magnetic bearings

    DOE Patents [OSTI]

    Hull, J.R.

    1997-08-05T23:59:59.000Z

    A method and apparatus are disclosed for compressing magnetic flux to achieve high levitation pressures. Magnetic flux produced by a magnetic flux source travels through a gap between two high temperature superconducting material structures. The gap has a varying cross-sectional area to compress the magnetic flux, providing an increased magnetic field and correspondingly increased levitation force in the gap. 4 figs.

  8. DESIGN OF BEAM-EXTRACTION SEPTUM MAGNET FOR THE SNS.

    SciTech Connect (OSTI)

    TSOUPAS,N.; LEE,Y.Y.; RANK,J.; TUOZZOLO,J.

    2001-06-18T23:59:59.000Z

    The beam-extraction process from the SNS accumulator ring [1,2] requires a Lambertson septum magnet. In this paper we discuss the geometrical and magnetic field requirements of the magnet and present results obtained from two and three dimensional magnetic field calculations that shows the field quality in the regions of interest of the septum magnet.

  9. YEAR PALAEOMAGNETISM OPTION 5TH WEEK ENVIRONMENTAL MAGNETISM

    E-Print Network [OSTI]

    Niocaill, Conall Mac

    4TH YEAR ­ PALAEOMAGNETISM OPTION ­ 5TH WEEK ­ ENVIRONMENTAL MAGNETISM Questions to be investigated: 1. What is environmental magnetism? 2. What rock magnetic parameters are used in environmental magnetism? 3. What geologic parameters are contributing to the environmental magnetic signals? 4. How can we

  10. Superconducting Magnets Research for a Viable US Fusion Program

    E-Print Network [OSTI]

    refrigeration efficiency and nuclear heating handling. http://magnet.fsu.edu/~lee/plot/plot.htm HTS Range LTSSuperconducting Magnets Research for a Viable US Fusion Program Joseph V. Minervini, Leslie Gaithersburg Marriott Washingtonian Center #12;Magnet Technology Enables Magnetic Confinement Fusion · Magnets

  11. Bose Glass of Quasiparticles in Doped Quantum Magnet Gregory S. Boebinger, National High Magnetic Field Laboratory

    E-Print Network [OSTI]

    Weston, Ken

    Bose Glass of Quasiparticles in Doped Quantum Magnet Gregory S. Boebinger, National High Magnetic. This BEC can localize in the presence of disorder caused by Br- doping to form a Bose Glass. The BEC-Bose Glass (BEC-BG) transition can be carefully controlled by magnetic field, allowing us to sensitively

  12. Superconducting Magnet Safety Nuclear Magnetic Resonance (NMR) facilities present unique hazards not found in most

    E-Print Network [OSTI]

    Maroncelli, Mark

    Superconducting Magnet Safety Nuclear Magnetic Resonance (NMR) facilities present unique hazards not found in most laboratory environments. The NMR facilities maintain superconducting magnets which have the units. Facility design and installation: Design and installation of a new NMR facility requires a number

  13. ECE 390 Electric & Magnetic Fields Catalog Description: Static and quasi-static electric and magnetic fields.

    E-Print Network [OSTI]

    Engineering Magnetics, ECE 593 Structure: Three 80-minute lectures per week Instructors: A. Weisshaar (primaryECE 390 ­ Electric & Magnetic Fields Catalog Description: Static and quasi-static electric and magnetic fields. Credits: 4 Terms Offered: Fall Prerequisites: MTH 255, ENGR 203 (concurrent enrollment

  14. Compatibility of Physics and Engineering in Magnetic Fusion White Paper on Magnetic Fusion Priorities

    E-Print Network [OSTI]

    Compatibility of Physics and Engineering in Magnetic Fusion White Paper on Magnetic Fusion.edu (Dated: July 14, 2012) The compatibility of the requirements of physics and engineering is the fundamental issue in the achievement of useful magnetic fusion energy. Issues that must be addressed include

  15. Magnetic anisotropy in Fe-25Cr-12Co-1Si alloy induced by external magnetic field

    E-Print Network [OSTI]

    Qin, Lu-Chang

    Magnetic anisotropy in Fe-25Cr-12Co-1Si alloy induced by external magnetic field ZHEN Liang( )1 of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China; 2. Department 27599-3255, USA Received 29 June 2006; accepted 15 January 2007 Abstract: Structural and magnetic

  16. On the Dynamics of Magnetic Fluids in Magnetic Resonance Padraig J. Cantillon-Murphy

    E-Print Network [OSTI]

    in Magnetic Resonance Imaging by Padraig J. Cantillon-Murphy B.E., Electrical and Electronic EngineeringOn the Dynamics of Magnetic Fluids in Magnetic Resonance Imaging by Padraig J. Cantillon-Murphy Submitted to the Department of Electrical Engineering and Computer Science in partial fulfillment

  17. Rock magnetic investigation of possible sources of the Bangui magnetic anomaly1 , M., Quesnel2*

    E-Print Network [OSTI]

    Boyer, Edmond

    Rock magnetic investigation of possible sources of the Bangui magnetic anomaly1 2 Ouabego1,2 , M slices of such28 metamorphic rocks, or by an iron-rich mafic source, or by a combination of these two29 source using constraints19 from satellite and ground magnetic field measurements, as well as from surface

  18. Optical pumping magnetic resonance in high magnetic fields: Characterization of nuclear relaxation during pumping

    E-Print Network [OSTI]

    Augustine, Mathew P.

    Optical pumping magnetic resonance in high magnetic fields: Characterization of nuclear relaxation during pumping Matthew P. Augustine and Kurt W. Zilm Department of Chemistry, Yale University, New Haven exchange with optically pumped Rb vapor is investigated in high magnetic field. Operation in a high field

  19. Real-Time Capable Methods to Determine the Magnet Temperature of Permanent Magnet

    E-Print Network [OSTI]

    Paderborn, Universität

    }@lea.upb.de Abstract--The permanent magnet synchronous motor (PMSM) is widely used in highly utilised automotive-based magnet temperature determination methods in PMSM. In this context, the existing publications can field. Keywords--PMSM, permanent magnet temperature, model- based real-time determination, motor control

  20. Tracking a nanosize magnetic particle using a magnetic force Dimitar Baronov, Sean B. Andersson and John Baillieul

    E-Print Network [OSTI]

    Andersson, Sean B.

    Tracking a nanosize magnetic particle using a magnetic force microscope Dimitar Baronov, Sean B. Andersson and John Baillieul Abstract-- A scheme for tracking nano-sized magnetic par- ticles using a magnetic force microscope (MFM) is introduced. The stray magnetic field of the particle induces a shift

  1. Electric Dipole Moment of Magnetic Monopole

    E-Print Network [OSTI]

    Makoto Kobayashi

    2007-03-07T23:59:59.000Z

    The electric dipole moment of magnetic monopoles with spin is studied in the N=2 supersymmetric gauge theory. The dipole moments of the electric charge distributions, as well as the dipole moments due to the magnetic currents, are calculated. The contribution of charge distribution of the fermion to the gyroelectric ratio is expressed by using zeta(3).

  2. Unentangling nuclear magnetic resonance Matthias Bechmann 1

    E-Print Network [OSTI]

    Stepney, Susan

    Unentangling nuclear magnetic resonance computing Matthias Bechmann 1 , John A. Clark 2 , Angelika of York, UK, YO10 5DD Abstract. Nuclear magnetic resonance (NMR) is typically thought of as a possible could be used to perform non-quantum computation: from addressable 3D memory, to a programmable 3D

  3. Fluorescent Magnetic Nanoparticles for Biomedical Applications

    E-Print Network [OSTI]

    Candea, George

    Fluorescent Magnetic Nanoparticles for Biomedical Applications V.M.Dao, Dr. G. Coullerez, Dr. L, the main goal was to synthesize and to characterize novel fluorescent magnetic nanoparticles. These nanoparticles (NPs) involve superparamagnetic iron oxide nanoparticles (SPIONs), a fluorescently-labeled polymer

  4. Ternary Dy-Er-Al magnetic refrigerants

    DOE Patents [OSTI]

    Gschneidner, K.A. Jr.; Takeya, Hiroyuki

    1995-07-25T23:59:59.000Z

    A ternary magnetic refrigerant material comprising (Dy{sub 1{minus}x}Er{sub x})Al{sub 2} for a magnetic refrigerator using the Joule-Brayton thermodynamic cycle spanning a temperature range from about 60K to about 10K, which can be adjusted by changing the Dy to Er ratio of the refrigerant. 29 figs.

  5. Ternary Dy-Er-Al magnetic refrigerants

    DOE Patents [OSTI]

    Gschneidner, Jr., Karl A. (Ames, IA); Takeya, Hiroyuki (Ibaraki, JP)

    1995-07-25T23:59:59.000Z

    A ternary magnetic refrigerant material comprising (Dy.sub.1-x Er.sub.x)Al.sub.2 for a magnetic refrigerator using the Joule-Brayton thermodynamic cycle spanning a temperature range from about 60K to about 10K, which can be adjusted by changing the Dy to Er ratio of the refrigerant.

  6. Migrating Songbirds Recalibrate Their Magnetic Compass Daily

    E-Print Network [OSTI]

    Murphy, Troy G.

    Migrating Songbirds Recalibrate Their Magnetic Compass Daily from Twilight Cues William W. Cochran, the same individuals migrated northward again. We suggest that birds orient with a magnetic compass­3) after a voyage of up to 25,000 km (4, 5). Migratory songbirds can orient on the basis of compass

  7. Wave propagation in the magnetic sun

    E-Print Network [OSTI]

    T. Hartlep; M. S. Miesch; N. N. Mansour

    2008-05-03T23:59:59.000Z

    This paper reports on efforts to simulate wave propagation in the solar interior. Presented is work on extending a numerical code for constant entropy acoustic waves in the absence of magnetic fields to the case where magnetic fields are present. A set of linearized magnetohydrodynamic (MHD) perturbation equations has been derived and implemented.

  8. Jeremy Carter Correctional Magnetic Coils for Beryllium-

    E-Print Network [OSTI]

    Hart, Gus

    Jeremy Carter Correctional Magnetic Coils for Beryllium- based Ion Plasma Chamber Physics 492R the voltage on the far end of the chamber must be turned on. Then a beam of ions is sent into the chamber was to develop and assemble two sets of identical magnetic coils for the Beryllium based plasma chamber

  9. Magnetic positioner having a single moving part

    DOE Patents [OSTI]

    Trumper, David L. (Plaistow, NH); Kim, Won-Jong (Cambridge, MA)

    1999-01-01T23:59:59.000Z

    A magnetic positioner is provided which is capable of providing long travel in two dimension and short travel in the remaining four dimensions. The positioner has a movable stage and a stator oriented adjacent and substantially parallel to this stage. At least three sets of first magnetic elements, which for preferred embodiments are winding sets capable of generating forces in two directions, are on the portion of the stator adjacent to the stage at any given time, and at least two second magnetic elements, which are magnet arrays for the preferred embodiment, are on the stage adjacent to the stator. At least one of the second magnetic elements overlaps multiple first magnetic elements for all positions of the stage relative to the stator, with one magnet overlapping multiple windings for one preferred embodiment of the invention and two magnets on the stage overlapping multiple windings on the stator for a second embodiment. The windings form a linear motor providing forces in both a corresponding long travel dimension and in a dimension perpendicular to both long travel dimensions.

  10. Magnetic/metallic thin films and nanostructures

    E-Print Network [OSTI]

    Lewis, Robert Michael

    examples. During the past decade applications of nano-scale magnetic devices to data storage have hadMagnetic/metallic thin films and nanostructures The College of William and MarY;'l Virginia http://www.as.wm.cdu/Faculty/Lukaszcw.html It is widely believed that revolutionary progress can be made as materials and devices are developed to operate

  11. DC-based magnetic field controller

    DOE Patents [OSTI]

    Kotter, D.K.; Rankin, R.A.; Morgan, J.P.

    1994-05-31T23:59:59.000Z

    A magnetic field controller is described for laboratory devices and in particular to dc operated magnetic field controllers for mass spectrometers, comprising a dc power supply in combination with improvements to a Hall probe subsystem, display subsystem, preamplifier, field control subsystem, and an output stage. 1 fig.

  12. The Plasma Magnet for Deep Space Exploration

    E-Print Network [OSTI]

    Shepherd, Simon

    . Expansion is halted by solar wind pressure is in balance with the magnetic pressure from the driven currentsW RF power ·Magnetic shielding of spacecraft from high energy solar particles ·Magneto-braking in magnetosphere of outer planets ·Electrical power generation from back emf on RF field coils from solar plasma

  13. Mechanical properties of insulators for Accelerator Magnets

    E-Print Network [OSTI]

    McDonald, Kirk

    ­ ~Mylar, glass fibre, epoxy resin ­ ~2mm thick · NbTi Superconducting Magnets ­ ~Kapton & epoxy ­ ~40µm thick · Nb3Sn Superconducting Magnets ­ ~S-glass fibre, epoxy resin, cyanate ester ­ ~400µm thick 3 #12 with epoxy resin 4 Useful to recap glass fibre/polymer composites #12;Glass fibre/epoxy composites 5 ·A

  14. DC-based magnetic field controller

    DOE Patents [OSTI]

    Kotter, Dale K. (Shelley, ID); Rankin, Richard A. (Ammon, ID); Morgan, John P,. (Idaho Falls, ID)

    1994-01-01T23:59:59.000Z

    A magnetic field controller for laboratory devices and in particular to dc operated magnetic field controllers for mass spectrometers, comprising a dc power supply in combination with improvements to a hall probe subsystem, display subsystem, preamplifier, field control subsystem, and an output stage.

  15. Testing neutrino magnetic moments with AGNs

    E-Print Network [OSTI]

    Kari Enqvist; Petteri Keränen; Jukka Maalampi

    1998-06-17T23:59:59.000Z

    We propose to test the magnetic transition moments of Majorana neutrinos by comparing the fluxes of different flavours of neutrinos coming from active galactic nuclei (AGN). We show that, with reasonable assumptions about the magnetic field of the AGN, it is possible to obtain limits on $\

  16. Discovery Research in Magnetic Fusion Energy

    E-Print Network [OSTI]

    Mauel, Michael E.

    a magnetic torus? Helical Coils (Wound in Place) +Toroidal Currents #12;Non-symmetric plasma torus J · P = 0 Surfaces of constant plasma pressure form nested tori not so easy without symmetry-symmetric plasma torus with external helical coils ("stellarator") #12;How to make a magnetic torus? Toroidal Field

  17. Cylindrical Hall Thrusters with Permanent Magnets

    SciTech Connect (OSTI)

    Raitses, Yevgeny; Merino, Enrique; Fisch, Nathaniel J.

    2010-10-18T23:59:59.000Z

    The use of permanent magnets instead of electromagnet coils for low power Hall thrusters can offer a significant reduction of both the total electric power consumption and the thruster mass. Two permanent magnet versions of the miniaturized cylindrical Hall thruster (CHT) of different overall dimensions were operated in the power range of 50W-300 W. The discharge and plasma plume measurements revealed that the CHT thrusters with permanent magnets and electromagnet coils operate rather differently. In particular, the angular ion current density distribution from the permanent magnet thrusters has an unusual halo shape, with a majority of high energy ions flowing at large angles with respect to the thruster centerline. Differences in the magnetic field topology outside the thruster channel and in the vicinity of the channel exit are likely responsible for the differences in the plume characteristics measured for the CHTs with electromagnets and permanent magnets. It is shown that the presence of the reversing-direction or cusp-type magnetic field configuration inside the thruster channel without a strong axial magnetic field outside the thruster channel does not lead to the halo plasma plume from the CHT. __________________________________________________

  18. Simulations of magnetic nanoparticle Brownian motion

    E-Print Network [OSTI]

    Daniel B Reeves; John B Weaver

    2014-03-25T23:59:59.000Z

    Magnetic nanoparticles are useful in many medical applications because they interact with biology on a cellular level thus allowing microenvironmental investigation. An enhanced understanding of the dynamics of magnetic particles may lead to advances in imaging directly in magnetic particle imaging (MPI) or through enhanced MRI contrast and is essential for nanoparticle sensing as in magnetic spectroscopy of Brownian motion (MSB). Moreover, therapeutic techniques like hyperthermia require information about particle dynamics for effective, safe, and reliable use in the clinic. To that end, we have developed and validated a stochastic dynamical model of rotating Brownian nanoparticles from a Langevin equation approach. With no field, the relaxation time toward equilibrium matches Einstein's model of Brownian motion. In a static field, the equilibrium magnetization agrees with the Langevin function. For high frequency or low amplitude driving fields, behavior characteristic of the linearized Debye approximation is reproduced. In a higher field regime where magnetic saturation occurs, the magnetization and its harmonics compare well with the effective field model. On another level, the model has been benchmarked against experimental results, successfully demonstrating that harmonics of the magnetization carry enough information to infer environmental parameters like viscosity and temperature.

  19. MERIT Magnet Testing Wednesday March 29

    E-Print Network [OSTI]

    McDonald, Kirk

    acquisition has been updated with the measured magnet constant. Cooldown displacement fixture and individual displacements have been recorded. Tuesdays measured magnet constant = .16T/79 amps. Power supply data segment voltage taps shown #12;Nitrogen Gas being vented. The vent pipe warms the N2 gas. It actually

  20. Dovetail spoke internal permanent magnet machine

    DOE Patents [OSTI]

    Alexander, James Pellegrino (Ballston Lake, NY); EL-Refaie, Ayman Mohamed Fawzi (Niskayuna, NY); Lokhandwalla, Murtuza (Clifton Park, NY); Shah, Manoj Ramprasad (Latham, NY); VanDam, Jeremy Daniel (West Coxsackie, NY)

    2011-08-23T23:59:59.000Z

    An internal permanent magnet (IPM) machine is provided. The IPM machine includes a stator assembly and a stator core. The stator core also includes multiple stator teeth. The stator assembly is further configured with stator windings to generate a stator magnetic field when excited with alternating currents and extends along a longitudinal axis with an inner surface defining a cavity. The IPM machine also includes a rotor assembly and a rotor core. The rotor core is disposed inside the cavity and configured to rotate about the longitudinal axis. The rotor assembly further includes a shaft. The shaft further includes multiple protrusions alternately arranged relative to multiple bottom structures provided on the shaft. The rotor assembly also includes multiple stacks of laminations disposed on the protrusions and dovetailed circumferentially around the shaft. The rotor assembly further includes multiple pair of permanent magnets for generating a magnetic field, which magnetic field interacts with the stator magnetic field to produce a torque. The multiple pair of permanent magnets are disposed between the stacks. The rotor assembly also includes multiple middle wedges mounted between each pair of the multiple permanent magnets.

  1. Materials Physics Applications: The National High Magnetic Field...

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

    Pulsed Magnetic Field Laboratory of the NHMFL in the form of a 1.4 GVA inertial storage motor-generator for high field pulsed magnets. In addition to the 60 Tesla Long Pulse Magnet...

  2. Experimental study of current-driven turbulence during magnetic reconnection

    E-Print Network [OSTI]

    Fox, William Randolph, II

    2009-01-01T23:59:59.000Z

    Magnetic reconnection is an important process in magnetized plasmas ranging from the laboratory to astrophysical scales. It enables the release of magnetic energy believed to power solar flares and magnetospheric substorms. ...

  3. Electric Field Control of Ferromagnetism and Magnetic Devices Using Multiferroics

    E-Print Network [OSTI]

    Heron, John Thomas

    2013-01-01T23:59:59.000Z

    deplete holes from a magnetic semiconductor (InMnAs) using aof holes in the magnetic semiconductor while the black arrowto investigate magnetic semiconductors in his group. I had

  4. A phenomenological constitutive model for magnetic shape memory alloys

    E-Print Network [OSTI]

    Kiefer, Bjoern

    2007-04-25T23:59:59.000Z

    A thermodynamics-based constitutive model is derived which predicts the nonlinear strain and magnetization response that magnetic shape memory alloys (MSMAs) exhibit when subjected to mechanical and magnetic loads. The model development is conducted...

  5. Characteristics of Graphitic Films for Carbon Based Magnetism and Electronics

    E-Print Network [OSTI]

    Hong, Jeongmin

    2009-01-01T23:59:59.000Z

    A. Rangwala, “Electricity and Magnetism,” 419 (1989) 81. S.L. Helm, “Defect-Induced Magnetism in Graphene,” Phys Rev. BGraphitic Films for Carbon Based Magnetism and Electronics A

  6. Exotic quantum magnetism and superfluidity in optical lattices

    E-Print Network [OSTI]

    Hung, Hsiang-Hsuan

    2011-01-01T23:59:59.000Z

    Chapter 4 Quantum Magnetism in spin-3/2 Systems with98 4.3.1 Quantum magnetism in 1D chains . . . . . . . . .98 4.3.2 Quantum magnetism in 2D square lattices . . . . 108

  7. Magnetism in nanoparticle LaCoO3

    E-Print Network [OSTI]

    Durand, A. M.

    2013-01-01T23:59:59.000Z

    Magnetism in nanoparticle LaCoO 3 A. M. Durand, 1 D. P.o ? 37 K. For T magnetism in bulk LCO is associatedto surfaces or interfaces. The magnetism of LaCoO 3 (LCO) is

  8. Magnetism of Complex Oxide Thin Films and Heterostructures

    E-Print Network [OSTI]

    Iwata, Jodi

    2012-01-01T23:59:59.000Z

    Introduction to Frustrated Magnetism, edited by C. Lacroix,Stöhr and H.C. Siegmann, in Magnetism: From Fundamentals to18] J. B. Goodenough, in Magnetism and the Chemical Bond, (

  9. Integrating giant microwave absorption with magnetic refrigeration in one

    E-Print Network [OSTI]

    Wang, Wei Hua

    Integrating giant microwave absorption with magnetic refrigeration in one multifunctional with magnetic refrigeration in one multifunctional material. This integration not only advances our-compression/expansion refrigeration, magnetic refrigeration exhibits the advantages of high energy efficiency and environment

  10. Simplified Modeling of Active Magnetic Regenerators Thomas Burdyny

    E-Print Network [OSTI]

    Victoria, University of

    , this technology uses the magnetization and demagnetization of environmentally neutral solid refrigerants ...............................................................................................................1 1.2 Magnetic RefrigerationSimplified Modeling of Active Magnetic Regenerators by Thomas Burdyny BEng., University of Victoria

  11. Negative magnetophoresis of submicron species in magnetic nanofluids

    E-Print Network [OSTI]

    Gonzalez, Lino A. (Lino Alberto), 1976-

    2009-01-01T23:59:59.000Z

    In this work we studied the focusing and trapping of submicron, nonmagnetic species immersed in a magnetic nanofluid under applied magnetic fields. Focusing was achieved using two pairs of permanent magnets, which forced ...

  12. Geometrically induced magnetic catalysis and critical dimensions

    E-Print Network [OSTI]

    Antonino Flachi; Kenji Fukushima; Vincenzo Vitagliano

    2015-02-21T23:59:59.000Z

    We discuss the combined effect of magnetic fields and geometry in interacting fermionic systems. At leading order in the heat-kernel expansion, the infrared singularity (that in flat space leads to the magnetic catalysis) is regulated by the chiral gap effect and the catalysis is deactivated by effect of the curvature. We discover that an infrared singularity may reappear from higher-order terms in the heat kernel expansion leading to a novel form of geometrically induced magnetic catalysis (absent in flat space). The dynamical mass squared is then modified not only due to the chiral gap effect by an amount proportional to the curvature, but also by a magnetic shift $\\propto (4-D)eB$ where $D$ represents the number of space-time dimensions. We argue that $D=4$ is a critical dimension across which the behaviour of the magnetic shift changes qualitatively.

  13. Geometrically induced magnetic catalysis and critical dimensions

    E-Print Network [OSTI]

    Flachi, Antonino; Vitagliano, Vincenzo

    2015-01-01T23:59:59.000Z

    We discuss the combined effect of magnetic fields and geometry in interacting fermionic systems. At leading order in the heat-kernel expansion, the infrared singularity (that in flat space leads to the magnetic catalysis) is regulated by the chiral gap effect and the catalysis is deactivated by effect of the curvature. We discover that an infrared singularity may reappear from higher-order terms in the heat kernel expansion leading to a novel form of geometrically induced magnetic catalysis (absent in flat space). The dynamical mass squared is then modified not only due to the chiral gap effect by an amount proportional to the curvature, but also by a magnetic shift $\\propto (4-D)eB$ where $D$ represents the number of space-time dimensions. We argue that $D=4$ is a critical dimension across which the behaviour of the magnetic shift changes qualitatively.

  14. MAGNETIC FIELDS FROM QCD PHASE TRANSITIONS

    SciTech Connect (OSTI)

    Tevzadze, Alexander G. [Faculty of Exact and Natural Sciences, Javakhishvili Tbilisi State University, 1 Chavchavadze Avenue, Tbilisi 0128 (Georgia); Kisslinger, Leonard; Kahniashvili, Tina [McWilliams Center for Cosmology and Department of Physics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213 (United States); Brandenburg, Axel, E-mail: aleko@tevza.org [Nordita, KTH Royal Institute of Technology and Stockholm University, Roslagstullsbacken 23, SE-10691 Stockholm (Sweden)

    2012-11-01T23:59:59.000Z

    We study the evolution of QCD phase transition-generated magnetic fields (MFs) in freely decaying MHD turbulence of the expanding universe. We consider an MF generation model that starts from basic non-perturbative QCD theory and predicts stochastic MFs with an amplitude of the order of 0.02 {mu}G and small magnetic helicity. We employ direct numerical simulations to model the MHD turbulence decay and identify two different regimes: a 'weakly helical' turbulence regime, when magnetic helicity increases during decay, and 'fully helical' turbulence, when maximal magnetic helicity is reached and an inverse cascade develops. The results of our analysis show that in the most optimistic scenario the magnetic correlation length in the comoving frame can reach 10 kpc with the amplitude of the effective MF being 0.007 nG. We demonstrate that the considered model of magnetogenesis can provide the seed MF for galaxies and clusters.

  15. Generation of the magnetic field in jets

    E-Print Network [OSTI]

    V. Urpin

    2006-05-22T23:59:59.000Z

    We consider dynamo action under the combined influence of turbulence and large-scale shear in sheared jets. Shear can stretch turbulent magnetic field lines in such a way that even turbulent motions showing mirror symmetry become suitable for generation of a large-scale magnetic field. We derive the integral induction equation governing the behaviour of the mean field in jets. The main result is that sheared jets may generate a large-scale magnetic field if shear is sufficiently strong. The generated mean field is mainly concentrated in a magnetic sheath surrounding the central region of a jet, and it exhibits sign reversals in the direction of the jet axis. Typically, the magnetic field in a sheath is dominated by the component along the jet that can reach equipartition with the kinetic energy of particles, The field in the central region of jets has a more disordered structure.

  16. Magnetic levitation system for moving objects

    DOE Patents [OSTI]

    Post, R.F.

    1998-03-03T23:59:59.000Z

    Repelling magnetic forces are produced by the interaction of a flux-concentrated magnetic field (produced by permanent magnets or electromagnets) with an inductively loaded closed electric circuit. When one such element moves with respect to the other, a current is induced in the circuit. This current then interacts back on the field to produce a repelling force. These repelling magnetic forces are applied to magnetically levitate a moving object such as a train car. The power required to levitate a train of such cars is drawn from the motional energy of the train itself, and typically represents only a percent or two of the several megawatts of power required to overcome aerodynamic drag at high speeds. 7 figs.

  17. Magnetic levitation system for moving objects

    DOE Patents [OSTI]

    Post, Richard F. (Walnut Creek, CA)

    1998-01-01T23:59:59.000Z

    Repelling magnetic forces are produced by the interaction of a flux-concentrated magnetic field (produced by permanent magnets or electromagnets) with an inductively loaded closed electric circuit. When one such element moves with respect to the other, a current is induced in the circuit. This current then interacts back on the field to produce a repelling force. These repelling magnetic forces are applied to magnetically levitate a moving object such as a train car. The power required to levitate a train of such cars is drawn from the motional energy of the train itself, and typically represents only a percent or two of the several megawatts of power required to overcome aerodynamic drag at high speeds.

  18. Axion emission from a magnetized neutron gas

    SciTech Connect (OSTI)

    Skobelev, V. V., E-mail: v.skobelev@inbox.ru [Moscow State Industrial University (Russian Federation)

    2011-01-15T23:59:59.000Z

    By using the polarization density matrix for a neutron in a magnetic field, the axion luminosity of magnetic neutron stars that is associated with the flip of the anomalous magnetic moment of degenerate nonrelativistic neutrons is calculated. It is shown that, at values of the magnetic-field induction in the region B Greater-Than-Or-Equivalent-To 10{sup 18} G, this mechanism of axion emission is dominant in 'young' neutron stars of temperature about a few tens of MeV units. At B {approx} 10{sup 17} G, it is one of the basic mechanisms. The Fermi energy of a degenerate neutron gas in a magnetic field is found, and it is shown that there is no such mechanism of axion emission in the degenerate case.

  19. Entanglement Entropy of Magnetic Electron Stars

    E-Print Network [OSTI]

    Tameem Albash; Clifford V. Johnson; Scott MacDonald

    2015-04-08T23:59:59.000Z

    We study the behavior of the entanglement entropy in $(2+1)$--dimensional strongly coupled theories via the AdS/CFT correspondence. We consider theories at a finite charge density with a magnetic field, with their holographic dual being Einstein-Maxwell-Dilaton theory in four dimensional anti--de Sitter gravity. Restricting to black hole and electron star solutions at zero temperature in the presence of a background magnetic field, we compute their holographic entanglement entropy using the Ryu-Takayanagi prescription for both strip and disk geometries. In the case of the electric or magnetic zero temperature black holes, we are able to confirm that the entanglement entropy is invariant under electric-magnetic duality. In the case of the electron star with a finite magnetic field, for the strip geometry, we find a discontinuity in the first derivative of the entanglement entropy as the strip width is increased.

  20. Magnetic Fields above the Surface of aSuperconductor with Internal Magnetism

    SciTech Connect (OSTI)

    Bluhm, Hendrik; /Stanford U., Phys. Dept. /SLAC, SSRl

    2007-06-26T23:59:59.000Z

    The author presents a method for calculating the magnetic fields near a planar surface of a superconductor with a given intrinsic magnetization in the London limit. He computes solutions for various magnetic domain boundary configurations and derives relations between the spectral densities of the magnetization and the resulting field in the vacuum half space, which are useful if the magnetization can be considered as a statistical quantity and its features are too small to be resolved individually. The results are useful for analyzing and designing magnetic scanning experiments. Application to existing data from such experiments on Sr{sub 2}RuO{sub 4} show that a domain wall would have been detectable, but the magnetic field of randomly oriented small domains and small defects may have been smaller than the experimental noise level.

  1. Static magnetic field concentration and enhancement using magnetic materials with positive permeability

    E-Print Network [OSTI]

    Sun, F

    2013-01-01T23:59:59.000Z

    In this paper a novel compressor for static magnetic fields is proposed based on finite embedded transformation optics. When the DC magnetic field passes through the designed device, the magnetic field can be compressed inside the device. After it passes through the device, one can obtain an enhanced static magnetic field behind the output surface of the device (in a free space region). We can also combine our compressor with some other structures to get a higher static magnetic field enhancement in a free space region. In contrast with other devices based on transformation optics for enhancing static magnetic fields, our device is not a closed structure and thus has some special applications (e.g., for controlling magnetic nano-particles for gene and drag delivery). The designed compressor can be constructed by using currently available materials or DC meta-materials with positive permeability. Numerical simulation verifies good performance of our device.

  2. Preparation and Magnetic Properties of MnBi-based Hard/Soft Composite Magnets

    SciTech Connect (OSTI)

    Ma, Yilong; Liu, Xubo; Gandha, Kinjal; Vuong, Nguyen V.; Yang, Y. B.; Yang, Jinbo; Poudyal, Narayan; Cui, Jun; Liu, J.Ping

    2014-05-07T23:59:59.000Z

    Bulk anisotropic composite magnets based on MnBi/Co(Fe) exhibiting the different morphology of the soft magnetic phase were prepared by powder metallurgy processing. First, single-phase MnBi bulk magnets were produced using a maximum energy product [(BH)m] of 6.3 MGOe at room temperature. The nanoscale soft phase with the different morphology was then added to form a composite magnet. It was observed that addition of magnetic soft-phase nanoparticles and nanoflakes causes a dramatic coercivity reduction. However, the addition of soft magnetic phase nanowires enhanced the composite magnetization without sacrificing the coercivity. Nevertheless, a kink was still observed on the demagnetization curves and the coercivity decreased when the soft-phase content was larger than 10 wt. %, which was caused by the agglomeration of the soft phase nanowires that also led to a decreased degree of texture.

  3. Magnetization and magnetostriction in highly magnetostrictive materials

    SciTech Connect (OSTI)

    Thoelke, J.B.

    1993-05-26T23:59:59.000Z

    The majority of this research has been in developing a model to describe the magnetostrictive properties of Terfenol-D, Tb{sub 1{minus}x}Dy{sub x}Fe{sub y} (x = 0.7-0.75 and y = 1.8--2.0), a rare earth-iron alloy which displays much promise for use in device applications. In the first chapter an introduction is given to the phenomena of magnetization and magnetostriction. The magnetic processes responsible for the observed magnetic properties of materials are explained. An overview is presented of the magnetic properties of rare earths, and more specifically the magnetic properties of Terfenol-D. In the second chapter, experimental results are presented on three composition of Tb{sub 1{minus}x}Dy{sub x}Fe{sub y} with x = 0.7, y= 1.9, 1.95, and x= 0.73, y= 1.95. The data were taken for various levels of prestress to show the effects of composition and microstructure on the magnetic and magnetostrictive properties of Terfenol-D. In the third chapter, a theoretical model is developed based on the rotation of magnetic domains. The model is used to explain the magnetic and magnetostrictive properties of Terfenol-D, including the observed negative strictions and large change in strain. The fourth chapter goes on to examine the magnetic properties of Terfenol-D along different crystallographic orientations. In the fifth chapter initial data are presented on the time dependence of magnetization in nickel.

  4. Magnetic changes observed in a solar flare

    SciTech Connect (OSTI)

    Moore, R.L.; Hurford, G.J.; Jones, H.P.; Kane, S.R.

    1984-01-01T23:59:59.000Z

    We present observations of a fairly large impulsive flare (1B/M4, starting 17:22 UT, 1980 April 10). Observations of the microwave/hard X-ray burst show the time development of the impulsive energy release. Chromospheric (H..cap alpha..) and photospheric (Fe I lambda5324) filtergrams and photospheric (Fe I lambda8688) magnetograms, intensitygrams, and velocitygrams show magnetic strucutre, flare emission, mass motion, and magnetic changes. From these observations, we conclude: 1. The flare was triggered by a small emerging magnetic bipole. 2. The peak impulsive energy release occurred in the explosive eruption of a filament from over the magnetic inversion line. Hence: a) The filament eruption was the magnetic transient in the heart of the primary energy release in the chromosphere and corona. b) The primary energy release did not occur in approximately stationary magnetic loops, but on field lines undergoing violet motion and drastic changes in direction. 3. In the photospheric magnetograph lines. Fe I lambda5324 and Fe I lambda8688, the impulsive peak of the flare produced emission in a unipolar area of a sunspot. In synchrony with the emission, the polarity of this area transiently reversed in the lambda8688 magnetigrams; apparently, this was an artifact of the line emission. 4. Within a few minutes after the explosive filament eruption. a) A permanent decrease in magnetic flux accompanied the truncation of an umbra. b) A permanent increase in magnetic flux accompanied the severance of the penumbral bridge to a satellite sunspot. Apparently, thee genuine photospheric magnetic changes were consequences of strong flare-wrought magnetic changes in the chromospher and corona.

  5. Stability Properties of Magnetic Tower Jets

    E-Print Network [OSTI]

    Masanori Nakamura; Hui Li; Shengtai Li

    2006-08-31T23:59:59.000Z

    Stability properties of ``magnetic tower'' jets propagating in the gravitationally stratified background have been examined by performing three-dimensional magnetohydrodynamic simulations. The current-carrying, Poynting flux-dominated magnetic tower jet, which possesses a highly wound helical magnetic field, is subject to the current-driven instability (CDI). We find that, under general physical conditions including small perturbations in the initial background profiles, the propagating magnetic tower jets develop the non-axisymmetric, $m=1$ kink mode of the CDI. The kink mode grows on the local Alfv\\'en crossing time scale. In addition, two types of kink modes appear in the system. At the central region where external thermal pressure confinement is strong, only the internal kink mode is excited and will grow. A large distance away from the central region where the external thermal pressure becomes low, the external kink mode is observed. As a result, the exterior of magnetic tower jets will be deformed into a large-scale wiggled structure. We also discuss extensively the different physical processes that contribute to the overall stability properties of the magnetic tower jets. Specifically, when the jet propagates in an initially unperturbed background, we find that they can survive the kink mode beyond the point predicted by the well-known Kruskal-Shafranov (K-S) criterion. The stabilization in this case comes mainly from the dynamical relaxation of magnetic twists during the propagation of magnetic towers; the magnetic pitch is reduced and the corresponding K-S critical wavelength becomes longer as the tower jet proceeds. Furthermore, we show that the pressure-driven and Kelvin-Helmholtz instabilities do not occur in the magnetic tower jets.

  6. Ion Rings for Magnetic Fusion

    SciTech Connect (OSTI)

    Greenly, John, B.

    2005-07-31T23:59:59.000Z

    This Final Technical Report presents the results of the program, Ion Rings for Magnetic Fusion, which was carried out under Department of Energy funding during the period August, 1993 to January, 2005. The central objective of the program was to study the properties of field-reversed configurations formed by ion rings. In order to reach this objective, our experimental program, called the Field-reversed Ion Ring Experiment, FIREX, undertook to develop an efficient, economical technology for the production of field-reversed ion rings. A field-reversed configuration (FRC) in which the azimuthal (field-reversing) current is carried by ions with gyro-radius comparable to the magnetic separatrix radius is called a field-reversed ion ring. A background plasma is required for charge neutralization of the ring, and this plasma will be confined within the ring's closed magnetic flux. Ion rings have long been of interest as the basis of compact magnetic fusion reactors, as the basis for a high-power accelerator for an inertial fusion driver, and for other applications of high power ion beams or plasmas of high energy density. Specifically, the FIREX program was intended to address the longstanding question of the contribution of large-orbit ions to the observed stability of experimental FRCs to the MHD tilt mode. Typical experimental FRCs with s {approx} 2-4, where s is the ratio of separatrix radius to ion gyro-radius, have been stable to tilting, but desired values for a fusion reactor, s > 20, should be unstable. The FIREX ring would consist of a plasma with large s for the background ions, but with s {approx} 1 for the ring ions. By varying the proportions of these two populations, the minimum proportion of large-orbit ions necessary for stability could be determined. The incorporation of large-orbit ions, perhaps by neutral-beam injection, into an FRC has been advanced for the purpose of stabilizing, heating, controlling angular momentum, and aiding the formation of a reactor-scale FRC, and the FIREX program was intended to test the ideas behind this approach. We will describe in this report the technological development path and advances in physics understanding that allowed FIREX to reach a regime in which ion rings were reproducibly created with up to about half the current necessary to produce field reversal. Unfortunately, the experiments were limited to this level by a fundamental, unanticipated aspect of the physics of strong ion rings in plasma. The FIREX ring is a strongly anisotropic, current-carrying population of ions moving faster than the Alfven speed in the background plasma. The rapidly changing ring current excites very large-amplitude Alfven waves in the plasma, and these waves strongly affect the ring, causing rapid energy loss in a way that is not compatible with the success of the ring trapping scenario around which FIREX was designed. The result was that FIREX rings were always very short-lived. We will discuss the implication of these results for possible future use of large-orbit ions in FRCs. In short, it appears that a certain range of the parameters characterizing the ring Alfven mach number and distribution function must be avoided to allow the existence of a long-lived energetic ion component in an FRC. This report will explain why FIREX experimental results cannot be directly scaled to quantitatively predict this range for a particular FRC configuration. This will require accurate, three-dimensional simulations. FIREX results do constitute a very good dataset for validating such a code, and simulations already carried out during this program provide a guide to the important physics involved.

  7. Broadband patterned magnetic microwave absorber

    SciTech Connect (OSTI)

    Li, Wei; Wu, Tianlong; Wang, Wei; Guan, Jianguo, E-mail: guanjg@whut.edu.cn [State Key Lab of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Zhai, Pengcheng [School of Science, Wuhan University of Technology, Wuhan 430070 (China)

    2014-07-28T23:59:59.000Z

    It is a tough task to greatly improve the working bandwidth for the traditional flat microwave absorbers because of the restriction of available material parameters. In this work, a simple patterning method is proposed to drastically broaden the absorption bandwidth of a conventional magnetic absorber. As a demonstration, an ultra-broadband microwave absorber with more than 90% absorption in the frequency range of 4–40 GHz is designed and experimentally realized, which has a thin thickness of 3.7?mm and a light weight equivalent to a 2-mm-thick flat absorber. In such a patterned absorber, the broadband strong absorption is mainly originated from the simultaneous incorporation of multiple ?/4 resonances and edge diffraction effects. This work provides a facile route to greatly extend the microwave absorption bandwidth for the currently available absorbing materials.

  8. The Cost of Superconducting Magnets as a Function of Stored Energy and Design Magnetic Induction Times the Field Volume

    SciTech Connect (OSTI)

    Green, Mike; Green, M.A.; Strauss, B.P.

    2007-08-27T23:59:59.000Z

    By various theorems one can relate the capital cost of superconducting magnets to the magnetic energy stored within that magnet. This is particularly true for magnet where the cost is dominated by the structure needed to carry the magnetic forces. One can also relate the cost of the magnet to the product of the magnetic induction and the field volume. The relationship used to estimate the cost the magnet is a function of the type of magnet it is. This paper updates the cost functions given in two papers that were published in the early 1990 s. The costs (escalated to 2007 dollars) of large numbers of LTS magnets are plotted against stored energy and magnetic field time field volume. Escalated costs for magnets built since the early 1990 s are added to the plots.

  9. Brookhaven-Built Magnet Will Catch Subatomic Debris

    ScienceCinema (OSTI)

    Peter Wanderer

    2013-07-22T23:59:59.000Z

    Peter Wanderer, head of Brookhaven's Superconducting Magnet Division, describes the magnet that's being built for the Facility for Rare Isotope Beams at Michigan State University

  10. advanced permanent magnet: Topics by E-print Network

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

    magnetic poles, so of generation of magnetic elds in astrophysical objects (or in electrically conducting uids) constitutes Khesin, Boris A. 68 Radiation hardness of permanent...

  11. A Renewable Electrochemical Magnetic Immunosensor Based on Gold...

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

    Renewable Electrochemical Magnetic Immunosensor Based on Gold Nanoparticle Labels. A Renewable Electrochemical Magnetic Immunosensor Based on Gold Nanoparticle Labels. Abstract: A...

  12. angle lipomas magnetic: Topics by E-print Network

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

    of ambient magnetic field because it is almost insensitive to the downstream distribution of magnetic field and emitting electrons. We apply our method to a new radio image...

  13. assessing dynamic magnetic: Topics by E-print Network

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

    0 Assessment of Carotid Flow Using Magnetic Resonance Imaging and Computational Fluid Dynamics) direct, model-independent velocity mapping using flow-encoded magnetic resonance...

  14. Oldest Known Magnet's Secrets Revealed Under High Pressures ...

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

    dichroism technique is readily applied to most magnetic materials without the need for isotope enrichment, and provides a true measure of long-range magnetic order." Other...

  15. U. S, Sovernment purposes. Introduction Quadrupole Magnet Measurements

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

    geometry for the measurements of the magnetic center, quadrupole fields and multipole coefficients of quadrupole magnets. The active length of the coil is longer than the...

  16. analyze magnetic flux: Topics by E-print Network

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

    of the cracks are the objective of the inversion process. The proposed procedure Reilly, James P. 47 Quantitative observation of magnetic flux distribution in new magnetic...

  17. High Field Magnet R&D in the USA

    E-Print Network [OSTI]

    Gourlay, S.A.

    2011-01-01T23:59:59.000Z

    beam instmmentation, accelerator physics shIdies, and designShldy in terms of accelerator physics and magnet design.magnet technology and accelerator physics and approach the

  18. Novel Electronic and Magnetic Properties of Graphene Nanoflakes...

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

    Electronic and Magnetic Properties of Graphene Nanoflakes in a Boron Nitride Layer. Novel Electronic and Magnetic Properties of Graphene Nanoflakes in a Boron Nitride Layer....

  19. artificial molecular magnets: Topics by E-print Network

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

    2013-01-04 18 Magnetic anisotropy of elongated thin ferromagnetic nano-islands for artificial spin ice arrays Physics Websites Summary: Magnetic anisotropy of elongated thin...

  20. artificial magnetic fields: Topics by E-print Network

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

    Galea 2003-02-10 74 Magnetic anisotropy of elongated thin ferromagnetic nano-islands for artificial spin ice arrays Physics Websites Summary: Magnetic anisotropy of elongated thin...

  1. artificial magnetic response: Topics by E-print Network

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

    2013-01-04 13 Magnetic anisotropy of elongated thin ferromagnetic nano-islands for artificial spin ice arrays Physics Websites Summary: Magnetic anisotropy of elongated thin...

  2. Optimal Magnetic Shield Design with Second–Order Cone ...

    E-Print Network [OSTI]

    2002-10-31T23:59:59.000Z

    Each car is equipped with several super-conducting magnet units which generate ... Passengers inside the car need to be shielded from the magnetic field.

  3. Dynamic Switching of the Spin Circulation in Tapered Magnetic...

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

    Dynamic Switching of the Spin Circulation in Tapered Magnetic Nanodisks Dynamic Switching of the Spin Circulation in Tapered Magnetic Nanodisks Print Monday, 22 April 2013 12:09...

  4. Ground Magnetics At Neal Hot Springs Geothermal Area (Colwell...

    Open Energy Info (EERE)

    Technique Ground Magnetics Activity Date 2011 - 2011 Usefulness not indicated DOE-funding Unknown Exploration Basis Magnetic surveys were conducted to gain a better...

  5. Core-Shell Structured Magnetic Ternary Nanocubes. | EMSL

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

    Structured Magnetic Ternary Nanocubes. Abstract: While transition metal-doped ferrite nanoparticles constitute an important class of soft magnetic nanomaterials with...

  6. Nuclear Magnetic Resonance Studies on Vanadium(IV) Electrolyte...

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

    Magnetic Resonance Studies on Vanadium(IV) Electrolyte Solutions for Vanadium Redox Flow Battery . Nuclear Magnetic Resonance Studies on Vanadium(IV) Electrolyte Solutions for...

  7. Characteristics of Graphitic Films for Carbon Based Magnetism and Electronics

    E-Print Network [OSTI]

    Hong, Jeongmin

    2009-01-01T23:59:59.000Z

    Spintronics: a spin-based electronics vision for theBased Magnetism and Electronics A Dissertation submitted inBased Magnetism and Electronics by Jeongmin Hong Doctor of

  8. alpha magnetic spectrometer: Topics by E-print Network

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

    23 24 25 Next Page Last Page Topic Index 1 Testing and Final Construction of the Superconducting Magnet for the Alpha Magnetic Spectrometer MIT - DSpace Summary: The Alpha...

  9. New Superconducting Magnet Will Lead to Next Generation of Wind...

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

    New Superconducting Magnet Will Lead to Next Generation of Wind Turbine Generators New Superconducting Magnet Will Lead to Next Generation of Wind Turbine Generators September 12,...

  10. Effects of non-radial magnetic field on measuring magnetic helicity transport across solar photosphere

    E-Print Network [OSTI]

    Song, Yongliang

    2015-01-01T23:59:59.000Z

    It is generally believed that the evolution of magnetic helicity has a close relationship with solar activity. Before the launch of SDO, earlier studies have mostly used MDI/SOHO line of sight magnetograms and assumed that magnetic fields are radial when calculating magnetic helicity injection rate from photospheric magnetograms. However, this assumption is not necessarily true. Here we use the vector magnetograms and line of sight magnetograms, both taken by HMI/SDO, to estimate the effects of non-radial magnetic field on measuring magnetic helicity injection rate. We find that: 1) The effect of non-radial magnetic field on estimating tangential velocity is relatively small; 2) On estimating magnetic helicity injection rate, the effect of non-radial magnetic field is strong when active regions are observed near the limb and is relatively small when active regions are close to disk center; 3) The effect of non-radial magnetic field becomes minor if the amount of accumulated magnetic helicity is the only conce...

  11. Magnets for Muon 6D Cooling Channels

    SciTech Connect (OSTI)

    Johnson, Rolland [Muons, Inc.; Flanagan, Gene [Muons, Inc.

    2014-09-10T23:59:59.000Z

    The Helical Cooling Channel (HCC), an innovative technique for six-dimensional (6D) cooling of muon beams using a continuous absorber inside superconducting magnets, has shown considerable promise based on analytic and simulation studies. The implementation of this revolutionary method of muon cooling requires high field superconducting magnets that provide superimposed solenoid, helical dipole, and helical quadrupole fields. Novel magnet design concepts are required to provide HCC magnet systems with the desired fields for 6D muon beam cooling. New designs feature simple coil configurations that produce these complex fields with the required characteristics, where new high field conductor materials are particularly advantageous. The object of the program was to develop designs and construction methods for HCC magnets and design a magnet system for a 6D muon beam cooling channel. If successful the program would develop the magnet technologies needed to create bright muon beams for many applications ranging from scientific accelerators and storage rings to beams to study material properties and new sources of energy. Examples of these applications include energy frontier muon colliders, Higgs and neutrino factories, stopping muon beams for studies of rare fundamental interactions and muon catalyzed fusion, and muon sources for cargo screening for homeland security.

  12. Manganese containing layer for magnetic recording media

    DOE Patents [OSTI]

    Lambeth, David N. (Pittsburgh, PA); Lee, Li-Lien (Santa Clara, CA); Laughlin, David E. (Pittsburgh, PA)

    1999-01-01T23:59:59.000Z

    The present invention provides for a magnetic recording media incorporating Mn-containing layers between a substrate and a magnetic layer to provide media having increased coercivity and lower noise. The Mn-containing layer can be incorporated in a rotating, translating or stationary recording media to operate in conjunction with magnetic transducing heads for recording and reading of magnetic data, as well as other applications. The magnetic recording medium of the invention preferably includes a Co or Co alloy film magnetic layer, and Mn-containing layer, preferably comprised of VMn, TiMn, MnZn, CrMnMo, CrMnW, CrMnV, and CrMnTi, and most preferably a CrMn alloy, disposed between the substrate and the magnetic layer to promote an epitaxial crystalline structure in the magnetic layer. The medium can further include seed layers, preferably polycrystalline MgO for longitudinal media, underlayers, and intermediate layers. Underlayers and intermediate layers are comprised of materials having either an A2 structure or a B2-ordered crystalline structure disposed between the seed layer and the magnetic layer. Materials having an A2 structure are preferably Cr or Cr alloys, such as CrV, CrMo, CrW and CrTi. Materials having a B2-ordered structure having a lattice constant that is substantially comparable to that of Cr, such as those preferably selected from the group consisting of NiAl, AILCo, FeAl, FeTi, CoFe, CoTi, CoHf, CoZr, NiTi, CuBe, CuZn, A-LMn, AlRe, AgMg, and Al.sub.2 FeMn.sub.2, and is most preferably FeAl or NiAl.

  13. Discovery of magnetic fields in hot subdwarfs

    E-Print Network [OSTI]

    S. J. O'Toole; S. Jordan; S. Friedrich; U. Heber

    2005-03-10T23:59:59.000Z

    We present polarisation measurements of sdB and sdO stars using FORS1 on the VLT. The observations were made as part of a project to determine whether magnetic fields in two super-metal-rich stars can explain their extreme abundance peculiarities. Field strengths of up to ~1.5 kG have been measured at varying levels of significance in each of our six targets, however no clear evidence was found between apparently normal subdwarfs and the metal-rich objects. The origin of the magnetic fields is unknown. We also discuss the implications of our measurements for magnetic flux conservation in late stages of stellar evolution.

  14. Measurement of the somatosensory magnetic evoked potential

    E-Print Network [OSTI]

    Pashkoff, Benjamin Lewis

    1983-01-01T23:59:59.000Z

    5 The SQUID is Mounted for Positioning Within the Carriage. 6 The Magnetic Field of a Square Loop. 7 The Magnetic Field Above the Square Loop. 8 A Steady Magnetic Field Between Two Square Coils. 9 The SQUID Detection Coil and Quartz Coil Form... assembly for the SQUID. This carriage assembly was designed by Col. C, P. Hatsell in order to give the probe four directions of movement. The carriage assembly (see figure 5) is constructed of PLEXIGLAS and aluminum with brass fittings where necessary...

  15. Graphene Nanoribbon in Sharply Localized Magnetic Fields

    E-Print Network [OSTI]

    Abdulaziz D. Alhaidari; Hocine Bahlouli; Abderrahim El Mouhafid; Ahmed Jellal

    2013-03-20T23:59:59.000Z

    We study the effect of a sharply localized magnetic field on the electron transport in a strip (ribbon) of graphene sheet, which allows to give results for the transmission and reflection probability through magnetic barriers. The magnetic field is taken as a single and double delta type localized functions, which are treated later as the zero width limit of gaussian fields. For both field configurations, we evaluate analytically and numerically their transmission and reflection coefficients. The possibility of spacial confinement due to the inhomogeneous field configuration is also investigated.

  16. Hysteresis prediction inside magnetic shields and application

    SciTech Connect (OSTI)

    Mori?, Igor [Observatoire de Paris, SYRTE, Avenue Denfert 77, 75014 Paris (France); CNES, Edouard Belin 18, 31400 Toulouse (France); De Graeve, Charles-Marie [SOGETI High Tech, chemin Laporte 3, 31300 Toulouse (France); Grosjean, Olivier [CNES, Edouard Belin 18, 31400 Toulouse (France); Laurent, Philippe [Observatoire de Paris, SYRTE, Avenue Denfert 77, 75014 Paris (France)

    2014-07-15T23:59:59.000Z

    We have developed a simple model that is able to describe and predict hysteresis behavior inside Mumetal magnetic shields, when the shields are submitted to ultra-low frequency (<0.01 Hz) magnetic perturbations with amplitudes lower than 60??T. This predictive model has been implemented in a software to perform an active compensation system. With this compensation the attenuation of longitudinal magnetic fields is increased by two orders of magnitude. The system is now integrated in the cold atom space clock called PHARAO. The clock will fly onboard the International Space Station in the frame of the ACES space mission.

  17. Nonlinear simulations to optimize magnetic nanoparticle hyperthermia

    SciTech Connect (OSTI)

    Reeves, Daniel B., E-mail: dbr@Dartmouth.edu; Weaver, John B. [Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755 (United States)

    2014-03-10T23:59:59.000Z

    Magnetic nanoparticle hyperthermia is an attractive emerging cancer treatment, but the acting microscopic energy deposition mechanisms are not well understood and optimization suffers. We describe several approximate forms for the characteristic time of Néel rotations with varying properties and external influences. We then present stochastic simulations that show agreement between the approximate expressions and the micromagnetic model. The simulations show nonlinear imaginary responses and associated relaxational hysteresis due to the field and frequency dependencies of the magnetization. This suggests that efficient heating is possible by matching fields to particles instead of resorting to maximizing the power of the applied magnetic fields.

  18. Homomorphic deconvolution of marine magnetic anomalies

    E-Print Network [OSTI]

    Jones, Leo David

    1976-01-01T23:59:59.000Z

    HOMOMORPIIIC DECONVOLUT ION OF MAR INE MAGNETIC ANOMAL I ES A Thesis by LEO DAVID JONES Submitted to the Graduate Colleoe of Texas Ahhi Unis ars i ty in partial fulfillment of the requirement for tne degree MASTEP, OF SCIENCE December 1975... Major Subject: Geophysics HOMOMORPHIC DECONVOLUT ION OF MARINE MAGNETIC ACNOMALIES A Thesis by LEO DAVID JONES Approved es to sty1e and content by: r"hi ~f C itt: Ch h~7 December 1976 ABSTRACT Homomorpi;ic Deconvolution of Marine Magnetic...

  19. Primordial Magnetic Fields in False Vacuum Inflation

    E-Print Network [OSTI]

    A. C. Davis; K. Dimopoulos

    1996-10-25T23:59:59.000Z

    We show that, during false vacuum inflation, a primordial magnetic field can be created, sufficiently strong to seed the galactic dynamo and generate the observed galactic magnetic fields. Considering the inflaton dominated regime, our field is produced by the Higgs-field gradients, resulting from a grand unified phase transition. The evolution of the field is followed from its creation through to the epoch of structure formation, subject to the relevant constraints. We find that it is possible to create a magnetic field of sufficient magnitude, provided the phase transition occurs during the final 5 e-foldings of the inflationary period.

  20. Noncommutative magnetic moment of charged particles

    SciTech Connect (OSTI)

    Adorno, T. C.; Gitman, D. M. [Instituto de Fisica, Universidade de Sao Paulo (Brazil); Shabad, A. E. [P.N. Lebedev Physics Institute, Moscow (Russian Federation); Vassilevich, D. V. [CMCC - Universidade Federal do ABC, Santo Andre, S.P. (Brazil); Department of Physics, St. Petersburg State University (Russian Federation)

    2011-10-15T23:59:59.000Z

    It has been argued that in noncommutative field theories, the sizes of physical objects cannot be taken smaller than an ''elementary length'' related to noncommutativity parameters. By gauge covariantly extending field equations of noncommutative U(1){sub *} theory to cover the presence of external sources, we find electric and magnetic fields produced by an extended static charge. We find that such a charge, apart from being an ordinary electric monopole, is also a magnetic dipole. By writing off the existing experimental clearance in the value of the lepton magnetic moments for the present effect, we get the bound on noncommutativity at the level of 10{sup 4} TeV.

  1. Surface Magnetization of Aperiodic Ising Quantum Chains

    E-Print Network [OSTI]

    L. Turban; B. Berche

    1997-09-11T23:59:59.000Z

    We study the surface magnetization of aperiodic Ising quantum chains. Using fermion techniques, exact results are obtained in the critical region for quasiperiodic sequences generated through an irrational number as well as for the automatic binary Thue-Morse sequence and its generalizations modulo p. The surface magnetization exponent keeps its Ising value, beta_s=1/2, for all the sequences studied. The critical amplitude of the surface magnetization depends on the strength of the modulation and also on the starting point of the chain along the aperiodic sequence.

  2. NATIONAL HIGH MAGNETIC FIELD LABORATORY REPORTSVOLUME 12 N0. 1 2005

    E-Print Network [OSTI]

    Weston, Ken

    , and Geochemistry 14 MAGNET SCIENCE & TECHNOLOGY Engineering Materials, Instrumentation, and Magnet Technology Magnet Science & Technology 42 7 including Engineering Materials, Instrumentation, and Magnet TechnologyNATIONAL HIGH MAGNETIC FIELD LABORATORY REPORTSVOLUME 12 · N0. 1 · 2005 OPERATED BY: FLORIDA STATE

  3. Digital lock-in detection of site-specific magnetism in magnetic materials

    DOE Patents [OSTI]

    Haskel, Daniel (Naperville, IL); Lang, Jonathan C. (Naperville, IL); Srajer, George (Oak Park, IL)

    2008-07-22T23:59:59.000Z

    The polarization and diffraction characteristics of x-rays incident upon a magnetic material are manipulated to provide a desired magnetic sensitivity in the material. The contrast in diffracted intensity of opposite helicities of circularly polarized x-rays is measured to permit separation of magnetic signals by element type and by atomic environment. This allows for the direct probing of magnetic signals from elements of the same species in nonequivalent atomic environments to better understand the behavior and characteristics of permanent magnetic materials. By using known crystallographic information together with manipulation of the polarization of x-rays having energies tuned near element-specific electronic excitations and by detecting and comparing the incident and diffracted photons at the same frequency, more accurate magnetic measurements can be made over shorter observation periods.

  4. Apparatus and method for continuous separation of magnetic particles from non-magnetic fluids

    DOE Patents [OSTI]

    Oder, Robin R. (Export, PA); Jamison, Russell E. (Lower Burrell, PA)

    2010-02-09T23:59:59.000Z

    A magnetic separator vessel (1) for separating magnetic particles from non-magnetic fluid includes a separation chamber having an interior and exterior wall, a top and bottom portion; a magnet (3) having first and second poles (2) positioned adjacent to the exterior wall, wherein the first pole is substantially diametrically opposed to the second pole; a inlet port (5) is directed into the top portion of the separation chamber, wherein the inlet port (5) is positioned adjacent to one of the first and second poles (2), wherein the inlet port (5) is adapted to transfer a mixture into the separation chamber; an underflow port (6) in communication with the bottom portion, wherein the underflow port (6) is adapted to receive the magnetic particles; and an overflow port (9) in communication with the separation chamber, wherein the overflow port (9) is adapted to receive the non-magnetic fluid.

  5. Overcoming inherent magnetic instability, preventing spin canting and magnetic coding in an assembly of ferrimagnetic nanoparticles

    SciTech Connect (OSTI)

    Dey, S.; Kumar, S., E-mail: kumars@phys.jdvu.ac.in [Department of Physics, Jadavpur University, Kolkata 700032 (India); Dey, S. K. [Department of Physics, Jadavpur University, Kolkata 700032 (India); Department of Physics, NITMAS, 24 Pargana (s) 743368 (India); Bagani, K.; Banerjee, S. [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Majumder, S. [Department of Physics, Jadavpur University, Kolkata 700032 (India); Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Roychowdhury, A.; Das, D. [UGC-DAE CSR, Kolkata Centre, III/LB-8, Bidhannagar, Kolkata 700098 (India); Reddy, V. R. [UGC-DAE CSR, University Campus, Khandwa Road, Indore 452001 (India)

    2014-08-11T23:59:59.000Z

    The authors find that for mechanically milled Ni{sub 0.5}Zn{sub 0.5}Fe{sub 2}O{sub 4} (?10?nm), the mechanical strain induced enhancement of anisotropy energy helps to retain stable magnetic order. The reduction of magnetization can be prevented by keeping the cation distribution of nanometric ferrites at its equilibrium ratio. Moreover, the sample can be used in coding, storing, and retrieving of binary bit (“0” and “1”) through magnetic field change.

  6. Electromagnetic Waves Reflectance of Graphene -- Magnetic Semiconductor Superlattice in Magnetic Field

    E-Print Network [OSTI]

    Kuzmin, Dmitry A; Shavrov, Vladimir G

    2014-01-01T23:59:59.000Z

    Electrodynamic properties of the graphene - magnetic semiconductor - graphene superlattice placed in magnetic field have been investigated theoretically in Faraday geometry with taking into account dissipation processes. Frequency and field dependences of the reflectance, transmittance and absorbtance of electromagnetic waves by such superlattice have been calculated for different numbers of periods of the structure and different sizes of the periods with using a transfer matrix method. The possibility of efficient control of electrodynamic properties of graphene - magnetic semiconductor - graphene superlattice has been shown.

  7. Tokamak Physics EXperiment (TPX): Toroidal magnet design, development and manufacture. SDRL 31, Magnet sensors. Volume 4

    SciTech Connect (OSTI)

    Weber, C.M. [Babcock and Wilcox Co., Lynchburg, VA (United States)

    1995-08-18T23:59:59.000Z

    The requirement for magnet sensors to verify the TF magnet system operation and aid in diagnostic assessment are defined. However, generally one does not specify such a system in the absence of a definition of the local I&C system. Also, one would expect that there would be great benefit (economy, redundancy, compatibility, etc.) in specifying common components for all of the magnet system. Thus specifying the sensors requirement we have tried to be flexible to accommodate future adjustments to these systems.

  8. Magnetic Propulsion of Intense Lithium Streams in a Tokamak Magnetic Field

    SciTech Connect (OSTI)

    Leonid E. Zakharov

    2002-03-13T23:59:59.000Z

    The paper gives the theory of magnetic propulsion of liquid lithium streams and their stability in tokamaks. In the approximation of a thin flowing layer the MHD equations are reduced to one integro-differential equation which takes into account the propulsion effect, viscosity and the drag force due to magnetic pumping and other interactions with the magnetic field. A criterion is obtained for the stabilization of the ''sausage'' instability of the streams by centrifugal force.

  9. Cooling system for superconducting magnet

    DOE Patents [OSTI]

    Gamble, B.B.; Sidi-Yekhlef, A.

    1998-12-15T23:59:59.000Z

    A cooling system is configured to control the flow of a refrigerant by controlling the rate at which the refrigerant is heated, thereby providing an efficient and reliable approach to cooling a load (e.g., magnets, rotors). The cooling system includes a conduit circuit connected to the load and within which a refrigerant circulates; a heat exchanger, connected within the conduit circuit and disposed remotely from the load; a first and a second reservoir, each connected within the conduit, each holding at least a portion of the refrigerant; a heater configured to independently heat the first and second reservoirs. In a first mode, the heater heats the first reservoir, thereby causing the refrigerant to flow from the first reservoir through the load and heat exchanger, via the conduit circuit and into the second reservoir. In a second mode, the heater heats the second reservoir to cause the refrigerant to flow from the second reservoir through the load and heat exchanger via the conduit circuit and into the first reservoir. 3 figs.

  10. Magnetic fields in Neutron Stars

    E-Print Network [OSTI]

    Viganò, Daniele; Miralles, Juan A; Rea, Nanda

    2015-01-01T23:59:59.000Z

    Isolated neutron stars show a diversity in timing and spectral properties, which has historically led to a classification in different sub-classes. The magnetic field plays a key role in many aspects of the neutron star phenomenology: it regulates the braking torque responsible for their timing properties and, for magnetars, it provides the energy budget for the outburst activity and high quiescent luminosities (usually well above the rotational energy budget). We aim at unifying this observational variety by linking the results of the state-of-the-art 2D magneto-thermal simulations with observational data. The comparison between theory and observations allows to place two strong constraints on the physical properties of the inner crust. First, strong electrical currents must circulate in the crust, rather than in the star core. Second, the innermost part of the crust must be highly resistive, which is in principle in agreement with the presence of a novel phase of matter so-called nuclear pasta phase.

  11. Magnetic insulation at finite temperatures

    SciTech Connect (OSTI)

    Goedecke, G. H.; Davis, Brian T.; Chen, Chiping [Physics Department, New Mexico State University, Las Cruces, New Mexico 88003 and Raytheon Missile Systems, 1151 E. Hermans Road, Tucson, Arizona 85706 (United States); Intense Beam Theoretical Research Group, Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 and Raytheon Missile Systems, 1151 E. Hermans Road, Tucson, Arizona 85706 (United States)

    2006-08-15T23:59:59.000Z

    A finite-temperature non-neutral plasma (FTNNP) theory of magnetically insulated (MI) electron flows in crossed-field vacuum devices is developed and applied in planar geometry. It is shown that, in contrast to the single type of MI flow predicted by traditional cold-plasma treatments, the nonlinear FTNNP equations admit five types of steady flow, of which three types are MI flows, including flows in which the electric field and/or the tangential velocity at the cathode may be zero or nonzero. It is also shown that finite-temperature Vlasov-Poisson treatments yield solutions for electron number densities and electrostatic potentials that are a subset of the FTNNP solutions. The algorithms that are used to solve the FTNNP equations numerically are discussed, and the numerical results are presented for several examples of the three types of MI flow. Results include prediction of the existence, boundaries, number density profiles, and other properties of sheaths of electrons in the anode-cathode gap.

  12. About the global magnetic fields of stars

    E-Print Network [OSTI]

    Bychkov, V D; Madej, J

    2013-01-01T23:59:59.000Z

    We present a review of observations of the stellar longitudinal (effective) magnetic field ($B_e$) and its properties. This paper also discusses contemporary views on the origin, evolution and structure of $B_e$.

  13. Magnetic fluctuations and heavy electron superconductivity

    SciTech Connect (OSTI)

    Norman, M.R.

    1988-01-01T23:59:59.000Z

    A magnetic fluctuation self-energy based on neutron scattering data is used to calculate mass renormalizations, and superconducting critical temperatures and order parameters, for various heavy electron metals.

  14. Nonlinear boundary value problem of magnetic insulation

    E-Print Network [OSTI]

    A. V. Sinitsyn

    2000-09-09T23:59:59.000Z

    On the basis of generalization of upper and lower solution method to the singular two point boundary value problems, the existence theorem of solutions for the system, which models a process of magnetic insulation in plasma is proved.

  15. Lunar magnetic field measurements with a cubesat

    E-Print Network [OSTI]

    Garrick-Bethell, Ian

    We have developed a mission concept that uses 3-unit cubesats to perform new measurements of lunar magnetic fields, less than 100 meters above the Moon’s surface. The mission calls for sending the cubesats on impact ...

  16. Power-Invariant Magnetic System Modeling 

    E-Print Network [OSTI]

    Gonzalez Dominguez, Guadalupe Giselle

    2012-10-19T23:59:59.000Z

    : the reluctance, as analogous to the electric resistance, should be a dissipative element instead it is an energy storage element. Furthermore, the two other elements are not defined. This difference has initiated a reevaluation of the conventional magnetic model...

  17. Magnetic Barcoded Hydrogel Microparticles for Multiplexed Detection

    E-Print Network [OSTI]

    Bong, Ki Wan

    Magnetic polymer particles have been used in a wide variety of applications ranging from targeting and separation to diagnostics and imaging. Current synthesis methods have limited these particles to spherical or deformations ...

  18. Single echo acquisition magnetic resonance imaging 

    E-Print Network [OSTI]

    McDougall, Mary Preston

    2006-04-12T23:59:59.000Z

    The dramatic improvement in magnetic resonance imaging (MRI) scan time over the past fifteen years through gradient-based methods that sample k-space more efficiently and quickly cannot be sustained, as thresholds regarding ...

  19. Helicopter magnetic survey conducted to locate wells

    SciTech Connect (OSTI)

    Veloski, G.A.; Hammack, R.W.; Stamp, V. (Rocky Mountain Oilfield Testing Center); Hall, R. (Rocky Mountain Oilfield Testing Center); Colina, K. (Rocky Mountain Oilfield Testing Center)

    2008-07-01T23:59:59.000Z

    A helicopter magnetic survey was conducted in August 2007 over 15.6 sq mi at the Naval Petroleum Reserve No. 3’s (NPR-3) Teapot Dome Field near Casper, Wyoming. The survey’s purpose was to accurately locate wells drilled there during more than 90 years of continuous oilfield operation. The survey was conducted at low altitude and with closely spaced flight lines to improve the detection of wells with weak magnetic response and to increase the resolution of closely spaced wells. The survey was in preparation for a planned CO2 flood for EOR, which requires a complete well inventory with accurate locations for all existing wells. The magnetic survey was intended to locate wells missing from the well database and to provide accurate locations for all wells. The ability of the helicopter magnetic survey to accurately locate wells was accomplished by comparing airborne well picks with well locations from an intense ground search of a small test area.

  20. Rotational hysteresis of exchange-spring magnets.

    SciTech Connect (OSTI)

    Jiang, J.S.; Bader, S.D.; Kaper, H.; Leaf, G.K.; Shull, R.D.; Shapiro, A.J.; Gornakov, V.S.; Nikitenko, V.I.; Platt, C.L.; Berkowitz, A.E.; David, S.; Fullerton, E.E.

    2002-03-27T23:59:59.000Z

    We highlight our experimental studies and micromagnetic simulations of the rotational hysteresis in exchange-spring magnets. Magneto-optical imaging and torque magnetometry measurements for SmCo/Fe exchange-spring films with uniaxial in-plane anisotropy show that the magnetization rotation created in the magnetically soft Fe layer by a rotating magnetic field is hysteretic. The rotational hysteresis is due to the reversal of the chirality of the spin spiral structure. Micromagnetic simulations reveal two reversal modes of the chirality, one at low fields due to an in-plane untwisting of the spiral, and the other, at high fields, due to an out-of-plane fanning of the spiral.

  1. Magnetic Activity in Stars, Discs and Quasars

    E-Print Network [OSTI]

    Donald Lynden-Bell

    2000-07-14T23:59:59.000Z

    Although magnetic fields in interstellar matter were postulated almost fifty years ago, magnetohydrodynamic theory was then much hampered by our inability to see what the magnetic field configurations were like and, after a decade of innovative development, cynics, not without some justification, began to claim that anything can happen when magnetism and an imaginative theorist get together. Thus cosmic lightning in particular received a bad press. More recently great advances in observational techniques that we shall hear of from Title, Beck, Moran and Mirabel have enabled us to see not only the sun's magnetic field with unprecedented clarity but the fields in galaxies, quasars and microquasars are now measured and not merely figments of fertile imaginations.

  2. Can (electric-magnetic) duality be gauged?

    SciTech Connect (OSTI)

    Bunster, Claudio [Centro de Estudios Cientificos (CECS), Casilla 1469, Valdivia (Chile); Max-Planck-Institut fuer Gravitationsphysik (Albert-Einstein-Institut), Muehlenberg 1, D-14476 Potsdam (Germany); Henneaux, Marc [Centro de Estudios Cientificos (CECS), Casilla 1469, Valdivia (Chile); Universite Libre de Bruxelles and International Solvay Institutes, ULB-Campus Plaine CP231, B-1050 Brussels (Belgium); Max-Planck-Institut fuer Gravitationsphysik (Albert-Einstein-Institut), Muehlenberg 1, D-14476 Potsdam (Germany)

    2011-02-15T23:59:59.000Z

    There exists a formulation of the Maxwell theory in terms of two vector potentials, one electric and one magnetic. The action is then manifestly invariant under electric-magnetic duality transformations, which are rotations in the two-dimensional internal space of the two potentials, and local. We ask the question: Can duality be gauged? The only known and battle-tested method of accomplishing the gauging is the Noether procedure. In its decanted form, it amounts to turning on the coupling by deforming the Abelian gauge group of the free theory, out of whose curvatures the action is built, into a non-Abelian group which becomes the gauge group of the resulting theory. In this article, we show that the method cannot be successfully implemented for electric-magnetic duality. We thus conclude that, unless a radically new idea is introduced, electric-magnetic duality cannot be gauged. The implication of this result for supergravity is briefly discussed.

  3. NANOSTRUCTURES, MAGNETIC SEMICONDUCTORS AND SPINELECTRONICS Paata Kervalishvili

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    to data storage, switching, lighting and other devices, can lead to substantially new hardwareNANOSTRUCTURES, MAGNETIC SEMICONDUCTORS AND SPINELECTRONICS Paata Kervalishvili Georgian Technical and manipulation on a nanometre scale, which allows the fabrication of nanostructures with the properties mainly

  4. Capacitive Stress Transducers in Model Dipole Magnets

    E-Print Network [OSTI]

    Benson, Christopher P.

    2010-07-14T23:59:59.000Z

    Capacitive stress transducers are used to measure mechanical stresses in the windings of superconducting dipole magnets. These transducers consist of a bonded laminate composed of alternating foils of stainless steel and a high-strength polymer...

  5. Development and characterization of the magnetic plasmatron

    E-Print Network [OSTI]

    Anziani, Felipe Rene, 1981-

    2004-01-01T23:59:59.000Z

    The purpose of this thesis is to investigate the plausibility of developing a low current plasmatron fuel reformer that utilizes magnetic fields to hydrodynamically induce spin of the arc discharge. The proof of principle, ...

  6. Magnetic island evolution in hot ion plasmas

    SciTech Connect (OSTI)

    Ishizawa, A.; Nakajima, N. [National Institute for Fusion Science, Toki 509-5292 (Japan); Waelbroeck, F. L.; Fitzpatrick, R.; Horton, W. [Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States)

    2012-07-15T23:59:59.000Z

    Effects of finite ion temperature on magnetic island evolution are studied by means of numerical simulations of a reduced set of two-fluid equations which include ion as well as electron diamagnetism in slab geometry. The polarization current is found to be almost an order of magnitude larger in hot than in cold ion plasmas, due to the strong shear of ion velocity around the separatrix of the magnetic islands. As a function of the island width, the propagation speed decreases from the electron drift velocity (for islands thinner than the Larmor radius) to values close to the guiding-center velocity (for islands of order 10 times the Larmor radius). In the latter regime, the polarization current is destabilizing (i.e., it drives magnetic island growth). This is in contrast to cold ion plasmas, where the polarization current is generally found to have a healing effect on freely propagating magnetic island.

  7. Flow-controlled magnetic particle manipulation

    DOE Patents [OSTI]

    Grate, Jay W [West Richland, WA; Bruckner-Lea, Cynthia J [Richland, WA; Holman, David A [Las Vegas, NV

    2011-02-22T23:59:59.000Z

    Inventive methods and apparatus are useful for collecting magnetic materials in one or more magnetic fields and resuspending the particles into a dispersion medium, and optionally repeating collection/resuspension one or more times in the same or a different medium, by controlling the direction and rate of fluid flow through a fluid flow path. The methods provide for contacting derivatized particles with test samples and reagents, removal of excess reagent, washing of magnetic material, and resuspension for analysis, among other uses. The methods are applicable to a wide variety of chemical and biological materials that are susceptible to magnetic labeling, including, for example, cells, viruses, oligonucleotides, proteins, hormones, receptor-ligand complexes, environmental contaminants and the like.

  8. PERFORMANCE OF DIPOLE MAGNETS IN HELIUM II

    E-Print Network [OSTI]

    Althaus, R.

    2010-01-01T23:59:59.000Z

    in Pressurized Superfluid Helium", EX5 40 11th InternationalOF DIPOLE MAGNETS IN HELIUM II R. Althaus, S. Cacpi, W.S.OF DIMLE NMMETS IN HELIUM II* R. Althaus, S. Caspl, W.S.

  9. Torus CLAS12-Superconducting Magnet Quench Analysis

    SciTech Connect (OSTI)

    Kashikhin, V S; Elouadhiri, L; Ghoshal, P K; Kashy, D; Makarov, A; Pastor, O; Quettier, L; Velev, G; Wiseman, M

    2014-06-01T23:59:59.000Z

    The JLAB Torus magnet system consists of six superconducting trapezoidal racetrack-type coils assembled in a toroidal configuration. These coils are wound with SSC-36 Nb-Ti superconductor and have the peak magnetic field of 3.6 T. The first coil manufacturing based on the JLAB design began at FNAL. The large magnet system dimensions (8 m diameter and 14 MJ of stored energy) dictate the need for quench protection. Each coil is placed in an aluminum case mounted inside a cryostat and cooled by 4.6 K supercritical helium gas flowing through a copper tube attached to the coil ID. The large coil dimensions and small cryostat thickness drove the design to challenging technical solutions, suggesting that Lorentz forces due to transport currents and eddy currents during quench and various failure scenarios are analyzed. The paper covers the magnet system quench analysis using the OPERA3d Quench code.

  10. Instrumentation for parallel magnetic resonance imaging

    E-Print Network [OSTI]

    Brown, David Gerald

    2007-04-25T23:59:59.000Z

    Parallel magnetic resonance (MR) imaging may be used to increase either the throughput or the speed of the MR imaging experiment. As such, parallel imaging may be accomplished either through a "parallelization" of the MR experiment, or by the use...

  11. Interaction of mesoscopic magnetic textures with superconductors

    E-Print Network [OSTI]

    Erdin, S.; Kayali, AF; Lyuksyutov, Igor F.; Pokrovsky, Valery L.

    2002-01-01T23:59:59.000Z

    Here we report a method to calculate the vortex and magnetization arrangement for a system of interacting superconductors and ferromagnets separated in space. The method is based on static London-Maxwell equations and the corresponding energy...

  12. Capacitive Stress Gauges in Model Dipole Magnets

    E-Print Network [OSTI]

    Ragland, R. Blake

    2009-06-09T23:59:59.000Z

    Capacitive transducers are used to measure mechanical stress in the windings of superconducting magnets. The transducer consists of a bonded laminate of alternating thin foils of stainless steel and high-strength polymer (polyimide). The thin...

  13. A Small Scale Magnetic Particle Relaxometer

    E-Print Network [OSTI]

    El Ghamrawy, Ahmed

    2013-12-09T23:59:59.000Z

    Magnetic Particle Imaging (MPI) is a newly found imaging modality. It utilizes superparamagnetic materials as tracers in the blood stream to obtain very high resolutions. MPI promises to have high sensitivity, high spatial resolution...

  14. Contactless magnetic brake for automotive applications

    E-Print Network [OSTI]

    Gay, Sebastien Emmanuel

    2009-05-15T23:59:59.000Z

    consumption due to power assistance, and requirement for anti-lock controls. To solve these problems, a contactless magnetic brake has been developed. This concept includes a novel flux-shunting structure to control the excitation flux generated by permanent...

  15. HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS

    E-Print Network [OSTI]

    Taylor, C.

    2011-01-01T23:59:59.000Z

    D. C. 'Niobium-Titanium Superconducting Material s ', in S.Nb -Ti and Nb3Sn superconductors. , •• ,""" s. S. Clamp, Tie14, 1982 HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS C.

  16. A Direct Search for Dirac Magnetic Monopoles

    SciTech Connect (OSTI)

    Mulhearn, Michael James

    2004-10-01T23:59:59.000Z

    Magnetic monopoles are highly ionizing and curve in the direction of the magnetic field. A new dedicated magnetic monopole trigger at CDF, which requires large light pulses in the scintillators of the time-of-flight system, remains highly efficient to monopoles while consuming a tiny fraction of the available trigger bandwidth. A specialized offline reconstruction checks the central drift chamber for large dE/dx tracks which do not curve in the plane perpendicular to the magnetic field. We observed zero monopole candidate events in 35.7 pb{sup -1} of proton-antiproton collisions at {radical}s = 1.96 TeV. This implies a monopole production cross section limit {sigma} < 0.2 pb for monopoles with mass between 100 and 700 GeV, and, for a Drell-Yan like pair production mechanism, a mass limit m > 360 GeV.

  17. Magnetic core studies at LBNL and LLNL

    E-Print Network [OSTI]

    Molvik, A.W.

    2008-01-01T23:59:59.000Z

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

  18. Magnetic Resonance Pulse Sequences for Fluorine-19

    E-Print Network [OSTI]

    Terry, Robin

    2014-07-11T23:59:59.000Z

    . Magnetic resonance imaging (MRI) has the ability to noninvasively track the transplanted cells to ensure they are in the desired destination. Unlike other MRI contrast agents, fluorine-19 has the ability to provide unambiguous cell tracking for two reasons...

  19. Magnetism in metal-organic capsules

    SciTech Connect (OSTI)

    Atwood, Jerry L.; Brechin, Euan K; Dalgarno, Scott J.; Inglis, Ross; Jones, Leigh F.; Mossine, Andrew; Paterson, Martin J.; Power, Nicholas P.; Teat, Simon J.

    2010-01-07T23:59:59.000Z

    Nickel and cobalt seamed metal-organic capsules have been isolated and studied using structural, magnetic and computational approaches. Antiferromagnetic exchange in the Ni capsule results from coordination environments enforced by the capsule framework.

  20. Magnetic monopole field exposed by electrons

    E-Print Network [OSTI]

    Béché, A; Van Tendeloo, G; Verbeeck, J

    2013-01-01T23:59:59.000Z

    Magnetic monopoles have provided a rich field of study, leading to a wide area of research in particle physics, solid state physics, ultra-cold gases, superconductors, cosmology, and gauge theory. So far, no true magnetic monopoles were found experimentally. Using the Aharonov-Bohm effect, one of the central results of quantum physics, shows however, that an effective monopole field can be produced. Understanding the effects of such a monopole field on its surroundings is crucial to its observation and provides a better grasp of fundamental physical theory. We realize the diffraction of fast electrons at a magnetic monopole field generated by a nanoscopic magnetized ferromagnetic needle. Previous studies have been limited to theoretical semiclassical optical calculations of the motion of electrons in such a monopole field. Solid state systems like the recently studied 'spin ice' provide a constrained system to study similar fields, but make it impossible to separate the monopole from the material. Free space ...

  1. Heat kernel asymptotics for magnetic Schrödinger operators

    SciTech Connect (OSTI)

    Bolte, Jens, E-mail: jens.bolte@rhul.ac.uk [Department of Mathematics, Royal Holloway, University of London, Egham TW20 0EX (United Kingdom)] [Department of Mathematics, Royal Holloway, University of London, Egham TW20 0EX (United Kingdom); Keppeler, Stefan, E-mail: stefan.keppeler@uni-tuebingen.de [Mathematisches Institut, Universität Tübingen, Auf der Morgenstelle 10, 72076 Tübingen (Germany)] [Mathematisches Institut, Universität Tübingen, Auf der Morgenstelle 10, 72076 Tübingen (Germany)

    2013-11-15T23:59:59.000Z

    We explicitly construct parametrices for magnetic Schrödinger operators on R{sup d} and prove that they provide a complete small-t expansion for the corresponding heat kernel, both on and off the diagonal.

  2. Independent Control of Multiple Magnetic Microrobots in Three Dimensions

    E-Print Network [OSTI]

    Sitti, Metin

    Independent Control of Multiple Magnetic Microrobots in Three Dimensions Eric Diller, Joshua method to independently control multiple sub-mm microrobots in three dimen- sions (3D) using magnetic of geometrically or magnetically distinct microrobots which assume different magnetization directions in a rotating

  3. Calculation Method of Permanent Magnet Pickups for Electric Guitars

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    in the 1930s, when Rickenbacker fitted out a guitar with a magnet and coils, thus designing the first magnetic to look at the types of magnetic circuit for the guitar pickups. We consider in this paper the most usual1 Calculation Method of Permanent Magnet Pickups for Electric Guitars G. Lemarquand and V

  4. Nuclear magnetic resonance offers new insights into Pu 239

    E-Print Network [OSTI]

    - 1 - Nuclear magnetic resonance offers new insights into Pu 239 May 29, 2012 Nuclear magnetic signal of plutonium 239's unique nuclear magnetic resonance signature has been detected by scientists on the subject, "Observation of 239 Pu Nuclear Magnetic Resonance," was published in the May 18 issue of Science

  5. Eddy Currents and Magnetic Calibrations in LDX using a

    E-Print Network [OSTI]

    Eddy Currents and Magnetic Calibrations in LDX using a "Copper Plasma" D.P. Boyle, PPPL M.E. Mauel Calibrate magnetic diagnostics positions and gains Find eddy current decay times Copper Plasma Operation electronically Would be better to measure positions and total gains magnetically #12;Goal: Eddy Currents Magnetic

  6. MODELING OF EDDY CURRENT LOSS AND TEMPERATURE OF THE MAGNETS

    E-Print Network [OSTI]

    Mi, Chunting "Chris"

    MODELING OF EDDY CURRENT LOSS AND TEMPERATURE OF THE MAGNETS IN PERMANENT MAGNET MACHINES@umich.edu Received 24 November 2010 Accepted 16 June 2011 The eddy current loss in the magnets of permanent magnet- mium-iron-boron (NdFeB), and slot/tooth harmonics, there is eddy current loss generated inside

  7. STOCHASTIC ACCELERATION BY A SINGLE WAVE IN A MAGNETIZED PLASMA

    E-Print Network [OSTI]

    Smith, G.R.

    2010-01-01T23:59:59.000Z

    An approach to thermonuclear fusion, initiated in the earlyapproaches to thermonuclear fusion by means of magnetic

  8. Ironless Permanent Magnet Motors: Three-Dimensional Analytical Calculation

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of the magnetic torque exerted between a tile permanent magnet radially magnetized and a winding in ironless structures. Such an expression can be used for calculating the magnetic torque transmitted between the stator or winding dimensions. The ironless structure we consider in this paper is commonly used for high speed

  9. High magnetic field ohmically decoupled non-contact technology

    DOE Patents [OSTI]

    Wilgen, John (Oak Ridge, TN) [Oak Ridge, TN; Kisner, Roger (Knoxville, TN) [Knoxville, TN; Ludtka, Gerard (Oak Ridge, TN) [Oak Ridge, TN; Ludtka, Gail (Oak Ridge, TN) [Oak Ridge, TN; Jaramillo, Roger (Knoxville, TN) [Knoxville, TN

    2009-05-19T23:59:59.000Z

    Methods and apparatus are described for high magnetic field ohmically decoupled non-contact treatment of conductive materials in a high magnetic field. A method includes applying a high magnetic field to at least a portion of a conductive material; and applying an inductive magnetic field to at least a fraction of the conductive material to induce a surface current within the fraction of the conductive material, the surface current generating a substantially bi-directional force that defines a vibration. The high magnetic field and the inductive magnetic field are substantially confocal, the fraction of the conductive material is located within the portion of the conductive material and ohmic heating from the surface current is ohmically decoupled from the vibration. An apparatus includes a high magnetic field coil defining an applied high magnetic field; an inductive magnetic field coil coupled to the high magnetic field coil, the inductive magnetic field coil defining an applied inductive magnetic field; and a processing zone located within both the applied high magnetic field and the applied inductive magnetic field. The high magnetic field and the inductive magnetic field are substantially confocal, and ohmic heating of a conductive material located in the processing zone is ohmically decoupled from a vibration of the conductive material.

  10. Permanent magnet design for high-speed superconducting bearings

    DOE Patents [OSTI]

    Hull, J.R.; Uherka, K.L.; Abdoud, R.G.

    1996-09-10T23:59:59.000Z

    A high temperature superconducting bearing including a permanent magnet rotor levitated by a high temperature superconducting structure is disclosed. The rotor preferably includes one or more concentric permanent magnet rings coupled to permanent magnet ring structures having substantially triangular and quadrangular cross-sections. Both alternating and single direction polarity magnet structures can be used in the bearing. 9 figs.

  11. ONDES DE SPIN MAGNETISM IN THE LIGHT RARE EARTH 'METALS

    E-Print Network [OSTI]

    Boyer, Edmond

    ONDES DE SPIN MAGNETISM IN THE LIGHT RARE EARTH 'METALS A. R. MACKINTOSH H. C. Mrsted Institute terres rares Ikgeres. Abstract. -The magnetic properties of the light rare earth metals are reviewed the last decade, the magnetism of the heavy rare earth metals is now rather well understood. The magnetic

  12. Acta Physicae Superficierum Vol VII 2004 EXPLORING ARTIFICIAL MAGNETISM

    E-Print Network [OSTI]

    Rau, Carl

    Acta Physicae Superficierum · Vol VII · 2004 EXPLORING ARTIFICIAL MAGNETISM FROM THIN FILMS of artificially structured, new magnetic materials play a fundamental role in modern science and technology. From thin films to patterned magnetic nano-structures, these magnetic materials and systems can be utilized

  13. SURFACE ORBITAL MAGNETISM Herv'e KUNZ \\Lambda

    E-Print Network [OSTI]

    SURFACE ORBITAL MAGNETISM Herv'e KUNZ \\Lambda Institut de Physique Th'eorique Ecole Polytechnique F, submitted to a magnetic field. Applying these results to orbital magnetism, we find that at high temperatures or weak magnetic fields the surface magnetisation is always paramag­ netic, but oscillations

  14. Numerical modelling and analysis of a room temperature magnetic

    E-Print Network [OSTI]

    Numerical modelling and analysis of a room temperature magnetic refrigeration system Thomas Frank and analysis of a room temperature magnetic refrigeration system Department: Fuel Cells and Solid State-dimensional mathematical model of an Active Magnetic Regenerator (AMR) system which is used for magnetic refrigeration

  15. Improved Magnetic Fusion Energy Economics Via Massive Resistive Electromagnets

    E-Print Network [OSTI]

    for cryogenic refrigeration plants needed to maintain the magnets' temperature near absolute zero, direct costsImproved Magnetic Fusion Energy Economics Via Massive Resistive Electromagnets Robert D. Woolley for magnetic fusion reactors and instead using resistive magnet designs based on cheap copper or aluminum

  16. Permanent magnet design for high-speed superconducting bearings

    DOE Patents [OSTI]

    Hull, John R. (5519 S. Bruner, Hinsdale, IL 60521); Uherka, Kenneth L. (830 Ironwood, Frankfort, IL 60423); Abdoud, Robert G. (13 Country Oaks La., Barrington Hills, IL 60010)

    1996-01-01T23:59:59.000Z

    A high temperature superconducting bearing including a permanent magnet rotor levitated by a high temperature superconducting structure. The rotor preferably includes one or more concentric permanent magnet rings coupled to permanent magnet ring structures having substantially triangular and quadrangular cross-sections. Both alternating and single direction polarity magnet structures can be used in the bearing.

  17. Tuning magnetic disorder in diluted magnetic semiconductors using high fields to 89 Tesla

    SciTech Connect (OSTI)

    Crooker, Scott A [Los Alamos National Laboratory; Samarth, Nitin [PENN STATE U

    2008-01-01T23:59:59.000Z

    We describe recent and ongoing studies at the National High Magnetic Field Laboratory at Los Alamos using the new '100 Tesla Multi-Shot Magnet', which is presently delivering fields up to {approx}89 T during its commissioning. We discuss the first experiments performed in this magnet system, wherein the linewidth of low-temperature photoluminescence spectra was used to directly reveal the degree of magnetic alloy disorder 'seen' by excitons in single Zn{sub 0.80}Cd{sub 0.22}Mn{sub 0.08}Se quantum wells. The magnetic potential landscape in II-VI diluted magnetic semiconductors (DMS) is typically smoothed when the embedded Mn{sup 2+} spins align in an applied field. However, an important (but heretofore untested) prediction of current models of compositional disorder is that magnetic alloy fluctuations in many DMS compounds should increase again in very large magnetic fields approaching 100 T. We observed precisely this increase above {approx}70 T, in agreement with a simple model of magnetic alloy disorder.

  18. Prospects for x-ray polarimetry measurements of magnetic fields in magnetized liner inertial fusion plasmas

    SciTech Connect (OSTI)

    Lynn, Alan G., E-mail: lynn@ece.unm.edu; Gilmore, Mark [Department of Electrical and Computer Engineering, University of New Mexico, Albuquerque, New Mexico 87131 (United States)

    2014-11-15T23:59:59.000Z

    Magnetized Liner Inertial Fusion (MagLIF) experiments, where a metal liner is imploded to compress a magnetized seed plasma may generate peak magnetic fields ?10{sup 4} T (100 Megagauss) over small volumes (?10{sup ?10}m{sup 3}) at high plasma densities (?10{sup 28}m{sup ?3}) on 100 ns time scales. Such conditions are extremely challenging to diagnose. We discuss the possibility of, and issues involved in, using polarimetry techniques at x-ray wavelengths to measure magnetic fields under these extreme conditions.

  19. MAGNET ENGINEERING AND TEST RESULTS OF THE HIGH FIELD MAGNET R AND D PROGRAM AT BNL.

    SciTech Connect (OSTI)

    COZZOLINO,J.; ANERELLA,M.; ESCALLIER,J.; GANETIS,G.; GHOSH,A.; GUPTA,R.; HARRISON,M.; JAIN,A.; MARONE,A.; MURATORE,J.; PARKER,B.; SAMPSON,W.; SOIKA,R.; WANDERER,P.

    2002-08-04T23:59:59.000Z

    The Superconducting Magnet Division at Brookhaven National Laboratory (BNL) has been carrying out design, engineering, and technology development of high performance magnets for future accelerators. High Temperature Superconductors (HTS) play a major role in the BNL vision of a few high performance interaction region (IR) magnets that would be placed in a machine about ten years from now. This paper presents the engineering design of a ''react and wind'' Nb{sub 3}Sn magnet that will provide a 12 Tesla background field on HTS coils. In addition, the coil production tooling as well as the most recent 10-turn R&D coil test results will be discussed.

  20. Permanent magnet electron beam ion source/trap systems with bakeable magnets for improved operation conditions

    SciTech Connect (OSTI)

    Schmidt, M., E-mail: mike.schmidt@dreebit.com [DREEBIT GmbH, 01109 Dresden (Germany); Zschornack, G.; Kentsch, U.; Ritter, E. [Department of Physics, Dresden University of Technology, 01062 Dresden, Germany and Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Ion Beam Physics and Materials Research, 01328 Dresden (Germany)] [Department of Physics, Dresden University of Technology, 01062 Dresden, Germany and Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Ion Beam Physics and Materials Research, 01328 Dresden (Germany)

    2014-02-15T23:59:59.000Z

    The magnetic system of a Dresden electron beam ion source (EBIS) generating the necessary magnetic field with a new type of permanent magnet made of high energy density NdFeB-type material operable at temperatures above 100?°C has been investigated and tested. The employment of such kind of magnets provides simplified operation without the time-consuming installation and de-installation procedures of the magnets for the necessary baking of the ion source after commissioning and maintenance work. Furthermore, with the use of a new magnetization technique the geometrical filling factor of the magnetic Dresden EBIS design could be increased to a filling factor of 100% leading to an axial magnetic field strength of approximately 0.5 T exceeding the old design by 20%. Simulations using the finite element method software Field Precision and their results compared with measurements are presented as well. It could be shown that several baking cycles at temperatures higher than 100?°C did not change the magnetic properties of the setup.

  1. Correction of Magnetization Sextupole in One-Meter Long Dipole Magnets Using Passing Superconductor

    E-Print Network [OSTI]

    Green, M.A.

    2011-01-01T23:59:59.000Z

    Fermilab Passive SuperconductorTest at the ICFA Workshop,Maydipole magnet. The superconductorin the passivecorrectorcanmagnetizationof the superconductingcable in the test

  2. Manganese-Aluminum-Based Magnets: Nanocrystalline t-MnAI Permanent Magnets

    SciTech Connect (OSTI)

    None

    2012-01-01T23:59:59.000Z

    REACT Project: Dartmouth is developing specialized alloys with magnetic properties superior to the rare earths used in today’s best magnets. EVs and renewable power generators typically use rare earths to turn the axles in their electric motors due to the magnetic strength of these minerals. However, rare earths are difficult and expensive to refine. Dartmouth will swap rare earths for a manganese-aluminum alloy that could demonstrate better performance and cost significantly less. The ultimate goal of this project is to develop an easily scalable process that enables the widespread use of low-cost and abundant materials for the magnets used in EVs and renewable power generators.

  3. Cerium-Based Magnets: Novel High Energy Permanent Magnet Without Critical Elements

    SciTech Connect (OSTI)

    None

    2012-01-01T23:59:59.000Z

    REACT Project: Ames Laboratory will develop a new class of permanent magnets based on the more commonly available element cerium for use in both EVs and renewable power generators. Cerium is 4 times more abundant and significantly less expensive than the rare earth element neodymium, which is frequently used in today’s most powerful magnets. Ames Laboratory will combine other metal elements with cerium to create a new magnet that can remain stable at the high temperatures typically found in electric motors. This new magnetic material will ultimately be demonstrated in a prototype electric motor, representing a cost-effective and efficient alternative to neodymium-based motors.

  4. The measurement and analysis of the magnetic field of a synchrotron light source magnet

    E-Print Network [OSTI]

    Graf, Udo Werner

    1994-01-01T23:59:59.000Z

    section of the magnet shows the symmetric distribution of the coils about the center line of the magnet. The iron yolk which surrounds the conductors is thermally insulated to enhance the efficiency of the cooling system. The entire magnet assembly... of charged particles in a 21 conductor that are exposed to an electric and a magnetic field. The force experienced by these particles is characterized by the Lorentz Equation, F=q(E+vxB) (3) The conductor used for the Hall probe has the shape of a...

  5. Laminated grid and web magnetic cores

    DOE Patents [OSTI]

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

    1984-01-01T23:59:59.000Z

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

  6. Multiscale dynamics of solar magnetic structures

    E-Print Network [OSTI]

    Vadim M. Uritsky; Joseph M. Davila

    2012-01-10T23:59:59.000Z

    Multiscale topological complexity of solar magnetic field is among the primary factors controlling energy release in the corona, including associated processes in the photospheric and chromospheric boundaries. We present a new approach for analyzing multiscale behavior of the photospheric magnetic flux underlying this dynamics as depicted by a sequence of high-resolution solar magnetograms. The approach involves two basic processing steps: (1) identification of timing and location of magnetic flux origin and demise events (as defined by DeForest et al., 2007) by tracking spatiotemporal evolution of unipolar and bipolar photospheric regions, and (2) analysis of collective behavior of the detected magnetic events using a generalized version of Grassberger - Procaccia correlation integral algorithm. The scale-free nature of the developed algorithms makes it possible to characterize the dynamics of the photospheric network across a wide range of distances and relaxation times. Three types of photospheric conditions are considered to test the method: a quiet photosphere, a solar active region (NOAA 10365) in a quiescent non-flaring state, and the same active region during a period of M-class flares. The results obtained show (1) the presence of a topologically complex asymmetrically fragmented magnetic network in the quiet photosphere driven by meso- and supergranulation, (2) the formation of non-potential magnetic structures with complex polarity separation lines inside the active region, and (3) statistical signatures of canceling bipolar magnetic structures coinciding with flaring activity in the active region. Each of these effects can represent an unstable magnetic configuration acting as an energy source for coronal dissipation and heating.

  7. Thermal Casimir Force between Magnetic Materials

    E-Print Network [OSTI]

    G. L. Klimchitskaya; B. Geyer; V. M. Mostepanenko

    2009-11-21T23:59:59.000Z

    We investigate the Casimir pressure between two parallel plates made of magnetic materials at nonzero temperature. It is shown that for real magnetodielectric materials only the magnetic properties of ferromagnets can influence the Casimir pressure. This influence is accomplished through the contribution of the zero-frequency term of the Lifshitz formula. The possibility of the Casimir repulsion through the vacuum gap is analyzed depending on the model used for the description of the dielectric properties of the metal plates.

  8. Safety of magnetic fusion facilities: Requirements

    SciTech Connect (OSTI)

    NONE

    1996-05-01T23:59:59.000Z

    This Standard identifies safety requirements for magnetic fusion facilities. Safety functions are used to define outcomes that must be achieved to ensure that exposures to radiation, hazardous materials, or other hazards are maintained within acceptable limits. Requirements applicable to magnetic fusion facilities have been derived from Federal law, policy, and other documents. In addition to specific safety requirements, broad direction is given in the form of safety principles that are to be implemented and within which safety can be achieved.

  9. A MAGNETIC CALIBRATION OF PHOTOSPHERIC DOPPLER VELOCITIES

    SciTech Connect (OSTI)

    Welsch, Brian T.; Fisher, George H. [Space Sciences Laboratory, University of California, Berkeley, CA 94720-7450 (United States); Sun, Xudong [W. W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305 (United States)

    2013-03-10T23:59:59.000Z

    The zero point of measured photospheric Doppler shifts is uncertain for at least two reasons: instrumental variations (from, e.g., thermal drifts); and the convective blueshift, a known correlation between intensity and upflows. Accurate knowledge of the zero point is, however, useful for (1) improving estimates of the Poynting flux of magnetic energy across the photosphere, and (2) constraining processes underlying flux cancellation, the mutual apparent loss of magnetic flux in closely spaced, opposite-polarity magnetogram features. We present a method to absolutely calibrate line-of-sight (LOS) velocities in solar active regions (ARs) near disk center using three successive vector magnetograms and one Dopplergram coincident with the central magnetogram. It exploits the fact that Doppler shifts measured along polarity inversion lines (PILs) of the LOS magnetic field determine one component of the velocity perpendicular to the magnetic field, and optimizes consistency between changes in LOS flux near PILs and the transport of transverse magnetic flux by LOS velocities, assuming that ideal electric fields govern the magnetic evolution. Previous calibrations fitted the center-to-limb variation of Doppler velocities, but this approach cannot, by itself, account for residual convective shifts at the limb. We apply our method to vector magnetograms of AR 11158, observed by the Helioseismic and Magnetic Imager aboard the Solar Dynamics Observatory, and find clear evidence of offsets in the Doppler zero point in the range of 50-550 m s{sup -1}. In addition, we note that a simpler calibration can be determined from an LOS magnetogram and Dopplergram pair from the median Doppler velocity among all near-disk-center PIL pixels. We briefly discuss shortcomings in our initial implementation, and suggest ways to address these. In addition, as a step in our data reduction, we discuss the use of temporal continuity in the transverse magnetic field direction to correct apparently spurious fluctuations in resolution of the 180 Degree-Sign ambiguity.

  10. A magnetically switched kicker for proton extraction

    SciTech Connect (OSTI)

    Dinkel, J.; Biggs, J.

    1989-03-01T23:59:59.000Z

    The application of magnetic current amplification and switching techniques to the generation of precise high current pulses for switching magnets is described. The square loop characteristic of Metglas tape wound cores at high excitation levels provides excellent switching characteristics for microsecond pulses. The rugged and passive nature of this type pulser makes it possible to locate the final stages of amplification at the load for maximum efficiency. 12 refs., 8 figs.

  11. Colour superconductivity in a strong magnetic field

    E-Print Network [OSTI]

    Efrain J. Ferrer; Vivian de la Incera; Cristina Manuel

    2005-11-30T23:59:59.000Z

    We explore the effects of an applied strong external magnetic field in a three flavour massless colour superconductor. The long-range component of the B field that penetrates the superconductor enhances some quark condensates, leading to a different condensation pattern. The external field also reduces the flavour symmetries in the system, and thus it changes drastically the corresponding low energy physics. Our considerations are relevant for the study of highly magnetized compact stars.

  12. Toroidal constant-tension superconducting magnetic energy storage units

    DOE Patents [OSTI]

    Herring, J.S.

    1992-11-03T23:59:59.000Z

    A superconducting magnetic energy storage unit is provided in which the magnet is wound in a toroidal fashion such that the magnetic field produced is contained only within the bore of the magnet, and thus producing a very low external field. The superconducting magnet includes a coolant channel disposed through the wire. The bore of the magnet comprises a storage volume in which cryogenic coolant is stored, and this volume supplies the coolant to be delivered to the coolant channel in the magnet. 6 figs.

  13. Tearing instability in relativistic magnetically dominated plasmas

    E-Print Network [OSTI]

    S. S. Komissarov; M. Barkov; M. Lyutikov

    2006-06-21T23:59:59.000Z

    Many astrophysical sources of high energy emission, such as black hole magnetospheres, superstrongly magnetized neutron stars (magnetars), and probably relativistic jets in Active Galactic Nuclei and Gamma Ray Bursts involve relativistically magnetically dominated plasma. In such plasma the energy density of magnetic field greatly exceeds the thermal and the rest mass energy density of particles. Therefore the magnetic field is the main reservoir of energy and its dissipation may power the bursting emission from these sources, in close analogy to Solar flares. One of the principal dissipative instabilities that may lead to release of magnetic energy is the tearing instability. In this paper we study, both analytically and numerically, the development of tearing instability in relativistically magnetically-dominated plasma using the framework of resistive magnetodynamics. We confirm and elucidate the previously obtained result on the growth rate of the tearing mode: the shortest growth time is the same as in the case of classical non-relativistic MHD, namely $\\tau =\\sqrt{\\tau_a \\tau_d}$ where $\\tau_a$ is the \\Alfven crossing time and $\\tau_d$ is the resistive time of a current layer.

  14. LIMITS OF Nb3Sn ACCELERATOR MAGNETS

    SciTech Connect (OSTI)

    Caspi, Shlomo; Ferracin, Paolo

    2005-05-01T23:59:59.000Z

    Pushing accelerator magnets beyond 10 T holds a promise of future upgrades to machines like the Tevatron at Fermilab and the LHC at CERN. Exceeding the current density limits of NbTi superconductor, Nb{sub 3}Sn is at present the only practical superconductor capable of generating fields beyond 10 T. Several Nb{sub 3}Sn pilot magnets, with fields as high as 16 T, have been built and tested, paving the way for future attempts at fields approaching 20 T. High current density conductor is required to generate high fields with reduced conductor volume. However this significantly increases the Lorentz force and stress. Future designs of coils and structures will require managing stresses of several 100's of MPa and forces of 10's of MN/m. The combined engineering requirements on size and cost of accelerator magnets will involve magnet technology that diverges from the one currently used with NbTi conductor. In this paper we shall address how far the engineering of high field magnets can be pushed, and what are the issues and limitations before such magnets can be used in particle accelerators.

  15. Magnet end design: The main injector dipoles

    SciTech Connect (OSTI)

    Ostiguy, J.F.

    1991-08-01T23:59:59.000Z

    From the accelerator designer standpoint, one of the quantities of interest in a magnet is the axially integrated transverse field. It is easily shown that the latter satisfies the equations of 2D magnetostatics. This is the basic theoretical result needed to design accelerator magnet ends. Unfortunately, axially integrated fields must be obtained from accurate 3D field maps and magnets ends have historically been designed using a cut and try approach. To a certain extent, this remains true even today; however, the advent of reliable 3D magnet design codes now permits to substantially reduce the costs associated with the construction of various prototypes. In this paper, the theory of magnet end design is reviewed. The design of the end of the dipole magnets of the proposed Fermilab Main Injector is analyzed in a detailed manner using TOSCA, a well-established 3D finite element code. Provided the limitations of the code are well understood by the user, the integrated field profile is satisfactorily predicted.

  16. MAGNETIC LOOPS IN THE QUIET SUN

    SciTech Connect (OSTI)

    Wiegelmann, T.; Solanki, S. K.; Barthol, P.; Gandorfer, A. [Max-Planck-Institut fuer Sonnensystemforschung, Max-Planck-Str. 2, 37191 Katlenburg-Lindau (Germany); Borrero, J. M.; Schmidt, W. [Kiepenheuer-Institut fuer Sonnenphysik, Schoeneckstr. 6, 79104 Freiburg (Germany); Pillet, V. MartInez; Bonet, J. A. [Instituto de Astrofisica de Canarias, C/Via Lactea s/n, 38200 La Laguna, Tenerife (Spain); Del Toro Iniesta, J. C. [Instituto de Astrofisica de Andalucia (CSIC), Apartado de Correos 3004, 18080 Granada (Spain); Domingo, V. [Grupo de Astronomia y Ciencias del Espacio, Universidad de Valencia, 46980 Paterna, Valencia (Spain); Knoelker, M. [High Altitude Observatory, National Center for Atmospheric Research Boulder, CO 80307 (United States); Title, A. M., E-mail: wiegelmann@mps.mpg.d [Lockheed Martin Solar and Astrophysics Laboratory, Bldg. 252, 3251 Hanover Street, Palo Alto, CA 94304 (United States)

    2010-11-10T23:59:59.000Z

    We investigate the fine structure of magnetic fields in the atmosphere of the quiet Sun. We use photospheric magnetic field measurements from SUNRISE/IMaX with unprecedented spatial resolution to extrapolate the photospheric magnetic field into higher layers of the solar atmosphere with the help of potential and force-free extrapolation techniques. We find that most magnetic loops that reach into the chromosphere or higher have one footpoint in relatively strong magnetic field regions in the photosphere. Ninety-one percent of the magnetic energy in the mid-chromosphere (at a height of 1 Mm) is in field lines, whose stronger footpoint has a strength of more than 300 G, i.e., above the equipartition field strength with convection. The loops reaching into the chromosphere and corona are also found to be asymmetric in the sense that the weaker footpoint has a strength B < 300 G and is located in the internetwork (IN). Such loops are expected to be strongly dynamic and have short lifetimes, as dictated by the properties of the IN fields.

  17. Thermodynamic functions of degenerate magnetized electron gas

    SciTech Connect (OSTI)

    Skobelev, V. V., E-mail: v.skobelev@inbox.ru [Moscow State Industrial University (Russian Federation)

    2011-11-15T23:59:59.000Z

    The Fermi energy, pressure, internal energy, entropy, and heat capacity of completely degenerate relativistic electron gas are calculated by numerical methods. It is shown that the maximum admissible magnetic field on the order of 10{sup 9} G in white dwarfs increases the pressure by a factor of 1.06 in the central region, where the electron concentration is {approx}10{sup 33} cm{sup -3}, while the equilibrium radius increases by approximately a factor of 1.03, which obviously cannot be observed experimentally. A magnetic field of {approx}10{sup 8} G or lower has no effect on the pressure and other thermodynamic functions. It is also shown that the contribution of degenerate electron gas to the total pressure in neutron stars is negligible compared to that of neutron gas even in magnetic fields with a maximum induction {approx}10{sup 17} G possible in neutron stars. The neutron beta-decay forbiddeness conditions in a superstrong magnetic field are formulated. It is assumed that small neutron stars have such magnetic fields and that pulsars with small periods are the most probable objects that can have super-strong magnetic fields.

  18. Novel Approach to Linear Accelerator Superconducting Magnet System

    SciTech Connect (OSTI)

    Kashikhin, Vladimir; /Fermilab

    2011-11-28T23:59:59.000Z

    Superconducting Linear Accelerators include a superconducting magnet system for particle beam transportation that provides the beam focusing and steering. This system consists of a large number of quadrupole magnets and dipole correctors mounted inside or between cryomodules with SCRF cavities. Each magnet has current leads and powered from its own power supply. The paper proposes a novel approach to magnet powering based on using superconducting persistent current switches. A group of magnets is powered from the same power supply through the common, for the group of cryomodules, electrical bus and pair of current leads. Superconducting switches direct the current to the chosen magnet and close the circuit providing the magnet operation in a persistent current mode. Two persistent current switches were fabricated and tested. In the paper also presented the results of magnetic field simulations, decay time constants analysis, and a way of improving quadrupole magnetic center stability. Such approach substantially reduces the magnet system cost and increases the reliability.

  19. Adjustable permanent magnet assembly for NMR and MRI

    DOE Patents [OSTI]

    Pines, Alexander; Paulsen, Jeffrey; Bouchard, Louis S; Blumich, Bernhard

    2013-10-29T23:59:59.000Z

    System and methods for designing and using single-sided magnet assemblies for magnetic resonance imaging (MRI) are disclosed. The single-sided magnet assemblies can include an array of permanent magnets disposed at selected positions. At least one of the permanent magnets can be configured to rotate about an axis of rotation in the range of at least +/-10 degrees and can include a magnetization having a vector component perpendicular to the axis of rotation. The single-sided magnet assemblies can further include a magnet frame that is configured to hold the permanent magnets in place while allowing the at least one of the permanent magnets to rotate about the axis of rotation.

  20. Chiral Disorder and Random Matrix Theory with Magnetism

    E-Print Network [OSTI]

    Maciej A. Nowak; Mariusz Sadzikowski; Ismail Zahed

    2013-04-30T23:59:59.000Z

    We revisit the concept of chiral disorder in QCD in the presence of a QED magnetic field |eH|. Weak magnetism corresponds to |eH| magnetism the reverse. Asymptotics (ultra-strong magnetism) is in the realm of perturbative QCD. We analyze weak magnetism using the concept of the quark return probability in the diffusive regime of chiral disorder. The result is in agreement with expectations from chiral perturbation theory. We analyze strong and ultra-strong magnetism in the ergodic regime using random matrix theory including the effects of finite temperature. The strong magnetism results are in agreement with the currently reported lattice data in the presence of a small shift of the Polyakov line. The ultra-strong magnetism results are consistent with expectations from perturbative QCD. We suggest a chiral random matrix effective action with matter and magnetism to analyze the QCD phase diagram near the critical points under the influence of magnetism.