National Library of Energy BETA

Sample records for 400-ton yin-yang magnet

  1. Design scoping study of the 12T Yin-Yang magnet system for the Tandem Mirror Next Step (TMNS). Final report

    SciTech Connect (OSTI)

    Not Available

    1981-09-01

    The overall objective of this engineering study was to determine the feasibility of designing a Yin-Yang magnet capable of producing a peak field in the windings of 12T for the Tandem Mirror Next Step (TMNS) program. As part of this technical study, a rough order of magnitude (ROM) cost estimate of the winding for this magnet was undertaken. The preferred approach to the winding design of the TMNS plug coil utilizes innovative design concepts to meet the structural, electrical and thermodynamic requirements of the magnet system. Structurally, the coil is radially partitioned into four sections, preventing the accumulation of the radial loads and reacting them into the structural case. To safely dissipate the 13.34 GJ of energy stored in each Yin-Yang magnet, the winding has been electrically subdivided into parallel or nested coils, each having its own power supply and protection circuitry. This arrangement effectively divides the total stored energy of the coils into manageable subsystems. The windings are cooled with superfluid helium II, operated at 1.8K and 1.2 atmospheres. The superior cooling capabilities of helium II have enabled the overall winding envelope to be minimized, providing a current density of 2367 A/CM/sup 2/, excluding substructure.

  2. Structural support conceptual studies for a Yin-Yang magnet of a tandem mirror reactor. Final report, September 1979-August 1980

    SciTech Connect (OSTI)

    Ojalvo, I.U.; Erickson, J.L.

    1980-07-01

    An investigation was made as to whether the TMR Yin-Yang coils will require elaborate external structural restraints. The approach taken was to use a simple coil case of compact design and to add and modify structural members to transfer loads from one coil to the other. The design considerations are described. (MOW)

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

    SciTech Connect (OSTI)

    Wu, Stephen G.; He, Lian; Wang, Qingzhao; Tang, Yinjie J.

    2015-03-20

    In ancient Chinese philosophy, Yin-Yang describes two contrary forces that are interconnected and interdependent. This concept also holds true in microbial cell factories, where Yin represents energy metabolism in the form of ATP, and Yang represents carbon metabolism. Current biotechnology can effectively edit the microbial genome or introduce novel enzymes to redirect carbon fluxes. On the other hand, microbial metabolism loses significant free energy as heat when converting sugar into ATP; while maintenance energy expenditures further aggravate ATP shortage. The limitation of cell powerhouse prevents hosts from achieving high carbon yields and rates. Via an Escherichia coli flux balance analysis model, we further demonstrate the penalty of ATP cost on biofuel synthesis. To ensure cell powerhouse being sufficient in microbial cell factories, we propose five principles: 1. Take advantage of native pathways for product synthesis. 2. Pursue biosynthesis relying only on pathways or genetic parts without significant ATP burden. 3. Combine microbial production with chemical conversions (semi-biosynthesis) to reduce biosynthesis steps. 4. Create minimal cells or use non-model microbial hosts with higher energy fitness. 5. Develop a photosynthesis chassis that can utilize light energy and cheap carbon feedstocks. Meanwhile, metabolic flux analysis can be used to quantify both carbon and energy metabolisms. The fluxomics results are essential to evaluate the industrial potential of laboratory strains, avoiding false starts and dead ends during metabolic engineering

  4. An ancient Chinese wisdom for metabolic engineering: Yin-Yang

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

    Wu, Stephen G.; He, Lian; Wang, Qingzhao; Tang, Yinjie J.

    2015-03-20

    In ancient Chinese philosophy, Yin-Yang describes two contrary forces that are interconnected and interdependent. This concept also holds true in microbial cell factories, where Yin represents energy metabolism in the form of ATP, and Yang represents carbon metabolism. Current biotechnology can effectively edit the microbial genome or introduce novel enzymes to redirect carbon fluxes. On the other hand, microbial metabolism loses significant free energy as heat when converting sugar into ATP; while maintenance energy expenditures further aggravate ATP shortage. The limitation of cell “powerhouse” prevents hosts from achieving high carbon yields and rates. Via an Escherichia coli flux balance analysismore » model, we further demonstrate the penalty of ATP cost on biofuel synthesis. To ensure cell powerhouse being sufficient in microbial cell factories, we propose five principles: 1. Take advantage of native pathways for product synthesis. 2. Pursue biosynthesis relying only on pathways or genetic parts without significant ATP burden. 3. Combine microbial production with chemical conversions (semi-biosynthesis) to reduce biosynthesis steps. 4. Create “minimal cells” or use non-model microbial hosts with higher energy fitness. 5. Develop a photosynthesis chassis that can utilize light energy and cheap carbon feedstocks. Meanwhile, metabolic flux analysis can be used to quantify both carbon and energy metabolisms. The fluxomics results are essential to evaluate the industrial potential of laboratory strains, avoiding false starts and dead ends during metabolic engineering« less

  5. This Week In Petroleum Printer-Friendly Version

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    1, 2005 (Next Release on May 18, 2005) Yin-Yang The ancient Chinese philosophical symbol yin-yang represents the understanding of the workings of the universe. This image may be...

  6. MAGNETS

    DOE Patents [OSTI]

    Hofacker, H.B.

    1958-09-23

    This patent relates to nmgnets used in a calutron and more particularly to means fur clamping an assembly of magnet coils and coil spacers into tightly assembled relation in a fluid-tight vessel. The magnet comprises windings made up of an assembly of alternate pan-cake type coils and spacers disposed in a fluid-tight vessel. At one end of the tank a plurality of clamping strips are held firmly against the assembly by adjustable bolts extending through the adjacent wall. The foregoing arrangement permits taking up any looseness which may develop in the assembly of coils and spacers.

  7. Cosmic magnetism

    SciTech Connect (OSTI)

    Seymour, P.

    1986-01-01

    This book deals with the cosmic magnetism in a non-mathematical way. It uses Faraday's very powerful and highly pictorial concept of lines of magnetic force and their associated physical properties to explain the structure and behavior of magnetic fields in extraterrestrial objects. Contents include: forces of nature; magnetic field of earth; solar and interplanetary magnetic fields; magnetic fields in the solar system; stars and pulsars; and magnetic fields of the milky way and other galaxies.

  8. Household magnets

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

    Now which is stronger, gravity or magnetism? What is going on? How do flexible refrigerator magnets work? Get 2 of these magnets, they are often the size of a business card....

  9. Magnetic shielding

    DOE Patents [OSTI]

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

    1987-10-06

    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 magnetic 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. 3 figs.

  10. Magnetic shielding

    DOE Patents [OSTI]

    Kerns, John A. (Livermore, CA); Stone, Roger R. (Walnut Creek, CA); Fabyan, Joseph (Livermore, CA)

    1987-01-01

    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 magnetic 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.

  11. Magnetic shielding

    DOE Patents [OSTI]

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

    1985-02-12

    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.

  12. Magnetic nanotubes

    DOE Patents [OSTI]

    Matsui, Hiroshi; Matsunaga, Tadashi

    2010-11-16

    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.

  13. Magnetic monopoles

    SciTech Connect (OSTI)

    Fryberger, D.

    1984-12-01

    In this talk on magnetic monopoles, first the author briefly reviews some historical background; then, the author describes what several different types of monopoles might look like; and finally the author discusses the experimental situation. 81 references.

  14. Cool Magnetic Molecules

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

    ... Underlying the magnetocaloric effect is the idea that magnetism is the result of the ... with the magnetic field, the magnetic entropy (disorder) of the system decreases; if ...

  15. Cool Magnetic Molecules

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

    enhanced magnetic refrigeration at very low temperatures. Not Your Mother's Refrigerator Magnets Some day soon, magnets could do more than clutter up the front of your...

  16. Magnetic Reconnection

    SciTech Connect (OSTI)

    Masaaki Yamada, Russell Kulsrud and Hantao Ji

    2009-09-17

    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.

  17. Superconducting magnet

    DOE Patents [OSTI]

    Satti, John A. (Naperville, IL)

    1980-01-01

    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.

  18. Permanent magnet assembly

    DOE Patents [OSTI]

    Chell, Jeremy; Zimm, Carl B.

    2006-12-12

    A permanent magnet assembly is disclosed that is adapted to provide a magnetic field across an arc-shaped gap. Such a permanent magnet assembly can be used, for example, to provide a time-varying magnetic field to an annular region for use in a magnetic refrigerator.

  19. Engineering problems of tandem-mirror reactors

    SciTech Connect (OSTI)

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

    1981-10-22

    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.

  20. Try This: Household Magnets

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

    Now which is stronger, gravity or magnetism? What is going on? How do flexible refrigerator magnets work? Get two of these magnets, they are often the size of a business card....

  1. Using Less Energy in the Kitchen on Thanksgiving | Department of Energy

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

    Using Less Energy in the Kitchen on Thanksgiving Using Less Energy in the Kitchen on Thanksgiving November 16, 2012 - 1:36pm Addthis You can use less energy in your kitchen and still prepare the perfect Thanksgiving feast. | Photo courtesy of ©iStockphoto.com/YinYang You can use less energy in your kitchen and still prepare the perfect Thanksgiving feast. | Photo courtesy of ©iStockphoto.com/YinYang Erin Connealy Communications Specialist, Office of Energy Efficiency and Renewable Energy

  2. Magnetic Membrane System

    DOE Patents [OSTI]

    McElfresh, Michael W.; (Livermore, CA); Lucas, Matthew S.; (Pasadena, CA)

    2004-12-30

    The present invention provides a membrane with magnetic particles. In one embodiment the membrane is created by mixing particles in a non-magnetic base. The membrane may act as an actuator, a sensor, a pump, a valve, or other device. A magnet is operatively connected to the membrane. The magnet acts on and changes the shape of the membrane.

  3. Magnetic Damping For Maglev

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

    Zhu, S.; Cai, Y.; Rote, D. M.; Chen, S. S.

    1998-01-01

    Magnetic damping is one of the important parameters that control the response and stability of maglev systems. An experimental study to measure magnetic damping directly is presented. A plate attached to a permanent magnet levitated on a rotating drum was tested to investigate the effect of various parameters, such as conductivity, gap, excitation frequency, and oscillation amplitude, on magnetic damping. The experimental technique is capable of measuring all of the magnetic damping coefficients, some of which cannot be measured indirectly.

  4. Nanocomposite Magnets: Transformational Nanostructured Permanent Magnets

    SciTech Connect (OSTI)

    2010-10-01

    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.

  5. Magnetic switch coupling to synchronize magnetic modulators

    DOE Patents [OSTI]

    Reed, Kim W. (Albuquerque, NM); Kiekel, Paul (Albuquerque, NM)

    1999-01-01

    Apparatus for synchronizing the output pulses from a pair of magnetic switches. An electrically conductive loop is provided between the pair of switches with the loop having windlings about the core of each of the magnetic switches. The magnetic coupling created by the loop removes voltage and timing variations between the outputs of the two magnetic switches caused by any of a variety of factors. The only remaining variation is a very small fixed timing offset caused by the geometry and length of the loop itself.

  6. Magnetic switch coupling to synchronize magnetic modulators

    DOE Patents [OSTI]

    Reed, K.W.; Kiekel, P.

    1999-04-27

    Apparatus for synchronizing the output pulses from a pair of magnetic switches is disclosed. An electrically conductive loop is provided between the pair of switches with the loop having windings about the core of each of the magnetic switches. The magnetic coupling created by the loop removes voltage and timing variations between the outputs of the two magnetic switches caused by any of a variety of factors. The only remaining variation is a very small fixed timing offset caused by the geometry and length of the loop itself. 13 figs.

  7. 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)

    2006-11-14

    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.

  8. Tamper resistant magnetic stripes

    DOE Patents [OSTI]

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

    1999-01-01

    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.

  9. Lensless Imaging of Magnetic Nanostructures

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

    Lensless Imaging of Magnetic Nanostructures Print Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging...

  10. Lensless Imaging of Magnetic Nanostructures

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

    Imaging of Magnetic Nanostructures Print Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in...

  11. Active magnetic regenerator

    DOE Patents [OSTI]

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

    1982-01-01

    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.

  12. Cool Magnetic Molecules

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

    Cool Magnetic Molecules Cool Magnetic Molecules Print Wednesday, 25 May 2011 00:00 Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost

  13. Magnetic nanohole superlattices

    DOE Patents [OSTI]

    Liu, Feng

    2013-05-14

    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.

  14. Noble gas magnetic resonator

    DOE Patents [OSTI]

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

    2014-04-15

    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.

  15. Rotating superconductor magnet for producing rotating lobed magnetic field lines

    DOE Patents [OSTI]

    Hilal, Sadek K. (Englewood Cliffs, NJ); Sampson, William B. (Bellport, NY); Leonard, Edward F. (Leonia, NJ)

    1978-01-01

    This invention provides a rotating superconductor magnet for producing a rotating lobed magnetic field, comprising a cryostat; a superconducting magnet in the cryostat having a collar for producing a lobed magnetic field having oppositely directed adjacent field lines; rotatable support means for selectively rotating the superconductor magnet; and means for energizing the superconductor magnet.

  16. Magnetically attached sputter targets

    DOE Patents [OSTI]

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

    1994-02-15

    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.

  17. Nanoscale, multidimensional artificial magnet created

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

    Nanoscale, multidimensional artificial magnet created Nanoscale, multidimensional artificial magnet created Applications might range from general magnetism, such as developing sensors, to information encoding. October 26, 2015 Researchers have created a nanoscale, artificial magnet by arranging an array of magnetic nano-islands along a geometry that is not found in natural magnets. As temperature is reduced, magnetic nanoislands (in blue) reach a one-dimensional static, ordered state, while

  18. Passive magnetic bearing system

    DOE Patents [OSTI]

    Post, Richard F.

    2014-09-02

    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.

  19. Pulse magnetic welder

    DOE Patents [OSTI]

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

    1984-01-01

    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.

  20. Magnetic latching solenoid

    DOE Patents [OSTI]

    Marts, D.J.; Richardson, J.G.; Albano, R.K.; Morrison, J.L. Jr.

    1995-11-28

    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. 2 figs.

  1. Cool Magnetic Molecules

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

    Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability

  2. Cool Magnetic Molecules

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

    Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability

  3. Cool Magnetic Molecules

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

    Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability

  4. Cool Magnetic Molecules

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

    Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability

  5. Cool Magnetic Molecules

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

    Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability

  6. Cool Magnetic Molecules

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

    Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability

  7. 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)

    1995-01-01

    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.

  8. Cool Magnetic Molecules

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

    Conversely, introducing a magnetic field to certain materials will cause the material to heat up. This happens because, as the spins in such (paramagnetic) materials align with...

  9. Magnetically leviated superconducting bearing

    DOE Patents [OSTI]

    Weinberger, Bernard R. (Avon, CT); Lynds, Jr., Lahmer (Glastonbury, CT)

    1993-01-01

    A magnetically levitated superconducting bearing includes a magnet (2) mounted on a shaft (12) that is rotatable around an axis of rotation and a Type II superconductor (6) supported on a stator (14) in proximity to the magnet (2). The superconductor (6) is positioned so that when it is cooled to its superconducting state in the presence of a magnetic field, it interacts with the magnet (2) to produce an attractive force that levitates the magnet (2) and supports a load on the shaft (12). The interaction between the superconductor (6) and magnet(2) also produces surface screening currents (8) that generate a repulsive force perpendicular to the load. The bearing also has means for maintaining the superconductor at a temperature below its critical temperature (16, 18). The bearing could also be constructed so the magnet (2) is supported on the stator (14) and the superconductor (6) is mounted on the shaft (12). The bearing can be operated by cooling the superconductor (6) to its superconducting state in the presence of a magnetic field.

  10. Passive magnetic bearing configurations

    DOE Patents [OSTI]

    Post, Richard F. (Walnut Creek, CA)

    2011-01-25

    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.

  11. Novel magnets and superconductors studied by high precision magnetic...

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

    Novel magnets and superconductors studied by high precision magnetic susceptometer under pressure An Inductor-capacitor circuit (LC circuit) is a simple, text-book level electric...

  12. Strain-assisted current-induced magnetization reversal in magnetic...

    Office of Scientific and Technical Information (OSTI)

    Strain-assisted current-induced magnetization reversal in magnetic tunnel junctions: A micromagnetic study with phase-field microelasticity Citation Details In-Document Search ...

  13. Magnet pole tips

    DOE Patents [OSTI]

    Thorn, C.E.; Chasman, C.; Baltz, A.J.

    1981-11-19

    An improved magnet more easily provides a radially increasing magnetic field, as well as reduced fringe field and requires less power for a given field intensity. The subject invention comprises a pair of spaced, opposed magnetic poles which further comprise a pair of pole roots, each having a pole tip attached to its center. The pole tips define the gap between the magnetic poles and at least a portion of each pole tip is separated from its associated pole root. The separation begins at a predetermined distance from the center of the pole root and increases with increasing radial distance while being constant with azimuth within that portion. Magnets in accordance with the subject invention have been found to be particularly advantageous for use in large isochronous cyclotrons.

  14. Magnet pole tips

    DOE Patents [OSTI]

    Thorn, Craig E. (Wading River, NY); Chasman, Chellis (Setauket, NY); Baltz, Anthony J. (Coram, NY)

    1984-04-24

    An improved magnet which more easily provides a radially increasing magnetic field, as well as reduced fringe field and requires less power for a given field intensity. The subject invention comprises a pair of spaced, opposed magnetic poles which further comprise a pair of pole roots, each having a pole tip attached to its center. The pole tips define the gap between the magnetic poles and at least a portion of each pole tip is separated from its associated pole root. The separation begins at a predetermined distance from the center of the pole root and increases with increasing radial distance while being constant with azimuth within that portion. Magnets in accordance with the subject invention have been found to be particularly advantageous for use in large isochronous cyclotrons.

  15. Lensless Imaging of Magnetic Nanostructures

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

    Lensless Imaging of Magnetic Nanostructures Lensless Imaging of Magnetic Nanostructures Print Wednesday, 28 March 2012 00:00 Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine. By studying the basics of magnetism, scientists aim to better understand the fundamental physical principles that govern magnetic systems, perhaps leading to important new technologies. The high brightness and coherence of the

  16. Lensless Imaging of Magnetic Nanostructures

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

    useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine. By studying the basics of magnetism,...

  17. Lensless Imaging of Magnetic Nanostructures

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

    the basics of magnetism, scientists aim to better understand the fundamental physical principles that govern magnetic systems, perhaps leading to important new technologies....

  18. 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...

  19. Speed Limit of Magnetic Recording

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

    from the original magnetization direction can be distinguished as changes in the grey scale contrast. In our images the original magnetization direction corresponds to light...

  20. PLUTONIUM OUGHT TO PRODUCE MAGNETISM.

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

    ... valence states. 1663 October 2015 5 electrical conductivity changes drastically in the presence of a magnetic field, allowing for new spintronic and magnetic- sensing devices. ...

  1. Large Magnetization at Carbon Surfaces

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

    exist even at room temperature. This makes carbon's magnetism an interesting natural effect with potential real-world applications if samples are thin enough. Magnetic hysteresis...

  2. Lensless Imaging of Magnetic Nanostructures

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

    in medicine. By studying the basics of magnetism, scientists aim to better understand the fundamental physical principles that govern magnetic systems, perhaps leading to important...

  3. Magnetic Refrigeration | GE Global Research

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

    Johnson, a materials scientist and project leader on GE's magnetic refrigeration project. ... materials would further improve the competitiveness of magnetic refrigeration technology. ...

  4. Lensless Imaging of Magnetic Nanostructures

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

    Print Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine. By studying...

  5. Magnetic field generator

    DOE Patents [OSTI]

    Krienin, Frank (Shoreham, NY)

    1990-01-01

    A magnetic field generating device provides a useful magnetic field within a specific retgion, while keeping nearby surrounding regions virtually field free. By placing an appropriate current density along a flux line of the source, the stray field effects of the generator may be contained. One current carrying structure may support a truncated cosine distribution, and it may be surrounded by a current structure which follows a flux line that would occur in a full coaxial double cosine distribution. Strong magnetic fields may be generated and contained using superconducting cables to approximate required current surfaces.

  6. Moment free toroidal magnet

    DOE Patents [OSTI]

    Bonanos, Peter (East Brunswick, NJ)

    1983-01-01

    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.

  7. Permanent magnet energy conversion machine with magnet mounting arrangement

    DOE Patents [OSTI]

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

    1999-01-01

    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.

  8. Magnetic Materials Group

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

    4-ID-C: Soft X-ray Magnetic Spectroscopy This beamline operates in the soft x-ray energy spectrum (500 - 2700 eV) using an electromagnetic helical undulator to provide circularly...

  9. Magnetic gripper device

    DOE Patents [OSTI]

    Meyer, R.E.

    1993-03-09

    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, Ross E. (Los Alamos, NM)

    1993-01-01

    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. Modular tokamak magnetic system

    DOE Patents [OSTI]

    Yang, Tien-Fang (Wayland, MA)

    1988-01-01

    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.

  12. Magnetic fluorescent lamp

    DOE Patents [OSTI]

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

    1983-12-29

    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.

  13. Magnetic coupling device

    DOE Patents [OSTI]

    Nance, Thomas A. (Aiken, SC)

    2009-08-18

    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.

  14. Permanent Magnet Ecr Plasma Source With Magnetic Field Optimization

    DOE Patents [OSTI]

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

    2000-12-19

    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.

  15. MAGNETIC NEUTRON SCATTERING

    SciTech Connect (OSTI)

    ZALIZNYAK,I.A.; LEE,S.H.

    2004-07-30

    Much of our understanding of the atomic-scale magnetic structure and the dynamical properties of solids and liquids was gained from neutron-scattering studies. Elastic and inelastic neutron spectroscopy provided physicists with an unprecedented, detailed access to spin structures, magnetic-excitation spectra, soft-modes and critical dynamics at magnetic-phase transitions, which is unrivaled by other experimental techniques. Because the neutron has no electric charge, it is an ideal weakly interacting and highly penetrating probe of matter's inner structure and dynamics. Unlike techniques using photon electric fields or charged particles (e.g., electrons, muons) that significantly modify the local electronic environment, neutron spectroscopy allows determination of a material's intrinsic, unperturbed physical properties. The method is not sensitive to extraneous charges, electric fields, and the imperfection of surface layers. Because the neutron is a highly penetrating and non-destructive probe, neutron spectroscopy can probe the microscopic properties of bulk materials (not just their surface layers) and study samples embedded in complex environments, such as cryostats, magnets, and pressure cells, which are essential for understanding the physical origins of magnetic phenomena. Neutron scattering is arguably the most powerful and versatile experimental tool for studying the microscopic properties of the magnetic materials. The magnitude of the cross-section of the neutron magnetic scattering is similar to the cross-section of nuclear scattering by short-range nuclear forces, and is large enough to provide measurable scattering by the ordered magnetic structures and electron spin fluctuations. In the half-a-century or so that has passed since neutron beams with sufficient intensity for scattering applications became available with the advent of the nuclear reactors, they have became indispensable tools for studying a variety of important areas of modern science, ranging from large-scale structures and dynamics of polymers and biological systems, to electronic properties of today's technological materials. Neutron scattering developed into a vast field, encompassing many different experimental techniques aimed at exploring different aspects of matter's atomic structure and dynamics. Modern magnetic neutron scattering includes several specialized techniques designed for specific studies and/or particular classes of materials. Among these are magnetic reflectometry aimed at investigating surfaces, interfaces, and multilayers, small-angle scattering for the large-scale structures, such as a vortex lattice in a superconductor, and neutron spin-echo spectroscopy for glasses and polymers. Each of these techniques and many others offer exciting opportunities for examining magnetism and warrant extensive reviews, but the aim of this chapter is not to survey how different neutron-scattering methods are used to examine magnetic properties of different materials. Here, we concentrate on reviewing the basics of the magnetic neutron scattering, and on the recent developments in applying one of the oldest methods, the triple axis spectroscopy, that still is among the most extensively used ones. The developments discussed here are new and have not been coherently reviewed. Chapter 2 of this book reviews magnetic small-angle scattering, and modern techniques of neutron magnetic reflectometry are discussed in Chapter 3.

  16. Freely oriented portable superconducting magnet

    DOE Patents [OSTI]

    Schmierer, Eric N.; Prenger, F. Coyne; Hill, Dallas D.

    2010-01-12

    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. Lensless Imaging of Magnetic Nanostructures

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

    Imaging of Magnetic Nanostructures Print Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine. By studying the basics of magnetism, scientists aim to better understand the fundamental physical principles that govern magnetic systems, perhaps leading to important new technologies. The high brightness and coherence of the ALS's soft x-rays have enabled scientists to apply lensless x-ray imaging for the

  18. Lensless Imaging of Magnetic Nanostructures

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

    Imaging of Magnetic Nanostructures Print Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine. By studying the basics of magnetism, scientists aim to better understand the fundamental physical principles that govern magnetic systems, perhaps leading to important new technologies. The high brightness and coherence of the ALS's soft x-rays have enabled scientists to apply lensless x-ray imaging for the

  19. Lensless Imaging of Magnetic Nanostructures

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

    Lensless Imaging of Magnetic Nanostructures Print Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine. By studying the basics of magnetism, scientists aim to better understand the fundamental physical principles that govern magnetic systems, perhaps leading to important new technologies. The high brightness and coherence of the ALS's soft x-rays have enabled scientists to apply lensless x-ray imaging

  20. Lensless Imaging of Magnetic Nanostructures

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

    Lensless Imaging of Magnetic Nanostructures Print Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine. By studying the basics of magnetism, scientists aim to better understand the fundamental physical principles that govern magnetic systems, perhaps leading to important new technologies. The high brightness and coherence of the ALS's soft x-rays have enabled scientists to apply lensless x-ray imaging

  1. Lensless Imaging of Magnetic Nanostructures

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

    Lensless Imaging of Magnetic Nanostructures Print Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine. By studying the basics of magnetism, scientists aim to better understand the fundamental physical principles that govern magnetic systems, perhaps leading to important new technologies. The high brightness and coherence of the ALS's soft x-rays have enabled scientists to apply lensless x-ray imaging

  2. Lensless Imaging of Magnetic Nanostructures

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

    Lensless Imaging of Magnetic Nanostructures Print Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine. By studying the basics of magnetism, scientists aim to better understand the fundamental physical principles that govern magnetic systems, perhaps leading to important new technologies. The high brightness and coherence of the ALS's soft x-rays have enabled scientists to apply lensless x-ray imaging

  3. Lensless Imaging of Magnetic Nanostructures

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

    Lensless Imaging of Magnetic Nanostructures Print Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine. By studying the basics of magnetism, scientists aim to better understand the fundamental physical principles that govern magnetic systems, perhaps leading to important new technologies. The high brightness and coherence of the ALS's soft x-rays have enabled scientists to apply lensless x-ray imaging

  4. Lensless Imaging of Magnetic Nanostructures

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

    Lensless Imaging of Magnetic Nanostructures Print Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine. By studying the basics of magnetism, scientists aim to better understand the fundamental physical principles that govern magnetic systems, perhaps leading to important new technologies. The high brightness and coherence of the ALS's soft x-rays have enabled scientists to apply lensless x-ray imaging

  5. Magnetic reconnection launcher

    DOE Patents [OSTI]

    Cowan, Maynard

    1989-01-01

    An electromagnetic launcher includes a plurality of electrical stages which are energized sequentially in synchrony with the passage of a projectile. Each stage of the launcher includes two or more coils which are arranged coaxially on either closed-loop or straight lines to form gaps between their ends. The projectile has an electrically conductive gap-portion that passes through all the gaps of all the stages in a direction transverse to the axes of the coils. The coils receive an electric current, store magnetic energy, and convert a significant portion of the stored magnetic energy into kinetic energy of the projectile by magnetic reconnection as the gap portion of the projectile moves through the gap. The magnetic polarity of the opposing coils is in the same direction, e.g. N-S-N-S. A gap portion of the projectile may be made from aluminum and is propelled by the reconnection of magnetic flux stored in the coils which causes accelerating forces to act upon the projectile at both the rear vertical surface of the projectile and at the horizontal surfaces of the projectile near its rear. The gap portion of the projectile may be flat, rectangular and longer than the length of the opposing coils and fit loosely within the gap between the opposing coils.

  6. Active magnetic regenerator

    DOE Patents [OSTI]

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

    1981-01-27

    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)

  7. Magnetic nanoparticle temperature estimation

    SciTech Connect (OSTI)

    Weaver, John B.; Rauwerdink, Adam M.; Hansen, Eric W.

    2009-05-15

    The authors present a method of measuring the temperature of magnetic nanoparticles that can be adapted to provide in vivo temperature maps. Many of the minimally invasive therapies that promise to reduce health care costs and improve patient outcomes heat tissue to very specific temperatures to be effective. Measurements are required because physiological cooling, primarily blood flow, makes the temperature difficult to predict a priori. The ratio of the fifth and third harmonics of the magnetization generated by magnetic nanoparticles in a sinusoidal field is used to generate a calibration curve and to subsequently estimate the temperature. The calibration curve is obtained by varying the amplitude of the sinusoidal field. The temperature can then be estimated from any subsequent measurement of the ratio. The accuracy was 0.3 deg. K between 20 and 50 deg. C using the current apparatus and half-second measurements. The method is independent of nanoparticle concentration and nanoparticle size distribution.

  8. Superconducting magnetic coil

    DOE Patents [OSTI]

    Aized, D.; Schwall, R.E.

    1999-06-22

    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.

  9. Superconducting magnetic coil

    DOE Patents [OSTI]

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

    1999-06-22

    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.

  10. Superconducting magnetic coil

    DOE Patents [OSTI]

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

    1996-06-11

    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.

  11. Magnetic imager and method

    DOE Patents [OSTI]

    Powell, J.; Reich, M.; Danby, G.

    1997-07-22

    A magnetic imager includes a generator for practicing a method of applying a background magnetic field over a concealed object, with the object being effective to locally perturb the background field. The imager also includes a sensor for measuring perturbations of the background field to detect the object. In one embodiment, the background field is applied quasi-statically. And, the magnitude or rate of change of the perturbations may be measured for determining location, size, and/or condition of the object. 25 figs.

  12. Magnetic imager and method

    DOE Patents [OSTI]

    Powell, James (Shoreham, NY); Reich, Morris (Kew Garden Hills, NY); Danby, Gordon (Wading River, NY)

    1997-07-22

    A magnetic imager 10 includes a generator 18 for practicing a method of applying a background magnetic field over a concealed object, with the object being effective to locally perturb the background field. The imager 10 also includes a sensor 20 for measuring perturbations of the background field to detect the object. In one embodiment, the background field is applied quasi-statically. And, the magnitude or rate of change of the perturbations may be measured for determining location, size, and/or condition of the object.

  13. Disorder-Induced Microscopic Magnetic Memory

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

    Disorder-Induced Microscopic Magnetic Memory Disorder-Induced Microscopic Magnetic Memory Print Wednesday, 26 October 2005 00:00 The magnetic-recording industry deliberately...

  14. Category:Magnetic Techniques | Open Energy Information

    Open Energy Info (EERE)

    Magnetic Techniques Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermalpower.jpg Looking for the Magnetic Techniques page? For detailed information on Magnetic...

  15. Magnet Motor Corp | Open Energy Information

    Open Energy Info (EERE)

    Magnet Motor Corp Jump to: navigation, search Name: Magnet Motor Corp. Place: Starnberg, Germany Zip: 82319 Sector: Vehicles Product: Magnet motor Corp has been developing and...

  16. Electronic Structure and Magnetism in Diluted Magnetic Semiconductors

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

    Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print Wednesday, 29 November 2006 00:00 The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted

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

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

    Forming Magnetic Filtering Material - Energy Innovation Portal Industrial Technologies Industrial Technologies Find More Like This Return to Search Magnetic Filtration Process, Magnetic Filtering Material, and Method of Forming Magnetic Filtering Material Oak Ridge National Laboratory Contact ORNL About This Technology Technology Marketing SummaryORNL researchers developed a new method for filtering materials and managing wastewater. This invention offers an integrated, intensified process

  18. Rotary magnetic heat pump

    DOE Patents [OSTI]

    Kirol, Lance D. (Shelly, ID)

    1988-01-01

    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.

  19. Rotary magnetic heat pump

    DOE Patents [OSTI]

    Kirol, L.D.

    1987-02-11

    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.

  20. Magnetic resonance apparatus

    DOE Patents [OSTI]

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

    1982-01-01

    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.

  1. 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...

  2. Magnetic Materials | Advanced Photon Source

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

    Materials Internal Magnetic Materials The Magnetic Material Group (MMG) is part of the X-ray Science Division (XSD) at the Advanced Photon Source (APS). Our research focuses on the...

  3. Magnet Cooldown and Warmup Model

    Energy Science and Technology Software Center (OSTI)

    1995-07-11

    This program evaluates cooldown/warmup performance of an SSC magnet or magnet strings, But can be applied to any other iron coldmass which is cooled or warmed by helium.

  4. Magnetic refrigeration apparatus and method

    DOE Patents [OSTI]

    Barclay, J.A.; Overton, W.C. Jr.; Stewart, W.F.

    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.

  5. Magnetic refrigeration apparatus and method

    DOE Patents [OSTI]

    Barclay, John A.; Overton, Jr., William C.; Stewart, Walter F.

    1984-01-01

    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.

  6. Magnetic reconnection launcher

    DOE Patents [OSTI]

    Cowan, M.

    1987-04-06

    An electromagnetic launcher includes a plurality of electrical stages which are energized sequentially in the launcher with the passage of a projectiles. Each stage of the launcher includes two or more coils which are arranged coaxially on either closed-loop or straight lines to form gaps between their ends. The projectile has an electrically conductive gap-portion that passes through all the gaps of all the stages in a direction transverse to the axes of the coils. The coils receive an electric current, store magnetic energy, and convert a significant portion of the stored magnetic energy into kinetic energy of the projectile moves through the gap. The magnetic polarity of the opposing coils is in the same direction, e.g. N-S-N-S. A gap portion of the projectile may be made from aluminum and is propelled by the reconnection of magnetic flux stored in the coils which causes accelerating forces to act upon the projectile and at the horizontal surfaces of the projectile near its rear. The gap portion of the projectile may be flat, rectangular and longer than the length of the opposing coils. The gap portion of the projectile permits substantially unrestricted distribution of the induced currents so that current densities are only high where the useful magnetic force is high. This allows designs which permit ohmic oblation from the rear surfaces of the gap portion of the projectile allowing much high velocities to be achieved. An electric power apparatus controls the electric power supplied to the opposing coils until the gap portion of the projectile substantially occupies the gap between the coils, at which time the coils are supplied with peak current quickly. 8 figs.

  7. Evolution of twisted magnetic fields

    SciTech Connect (OSTI)

    Zweibel, E.G.; Boozer, A.H.

    1985-02-01

    The magnetic field of the solar corona evolves quasistatically in response to slowly changing photospheric boundary conditions. The magnetic topology is preserved by the low resistivity of the solar atmosphere. We show that a magnetic flux coordinate system simplifies the problem of calculating field evolution with invariant topology. As an example, we calculate the equilibrium of a thin magnetic flux tube with small twist per unit length.

  8. Carbon Joins the Magnetic Club

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

    Press Release 29 May 2007 Carbon Joins the Magnetic Club summary written by Brad Plummer, SLAC Communication Office The exclusive club of magnetic elements officially has a new member-carbon. Using a proton beam and advanced x-ray techniques, SLAC researchers in collaboration with colleagues from LBNL and the University of Leipzig in Germany have finally put to rest doubts about carbon's ability to be made magnetic. "In the past, some groups thought they had discovered magnetic

  9. Ames Lab 101: Magnetic Refrigeration

    ScienceCinema (OSTI)

    Pecharsky, Vitalij

    2013-03-01

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

  10. Ames Lab 101: Magnetic Refrigeration

    SciTech Connect (OSTI)

    Pecharsky, Vitalij

    2011-01-01

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

  11. Low-temperature magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, J.A.

    1983-05-26

    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.

  12. Low-temperature magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, John A. (Los Alamos, NM)

    1985-01-01

    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.

  13. 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)

    2010-07-13

    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.

  14. Regenerator for Magnetic Refrigerants - Energy Innovation Portal

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

    Magnetic refrigeration is being investigated as an alternative to conventional gas ... materials may thus have improved properties for magnetic refrigeration. ...

  15. Iterative reconstruction of magnetic induction using Lorentz...

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

    Iterative reconstruction of magnetic induction using Lorentz transmission electron tomography Title Iterative reconstruction of magnetic induction using Lorentz transmission...

  16. Method of making permanent magnets

    DOE Patents [OSTI]

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

    1993-09-07

    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.

  17. Method of making permanent magnets

    DOE Patents [OSTI]

    McCallum, R. William (Ames, IA); Dennis, Kevin W. (Ames, IA); Lograsso, Barbara K. (Ames, IA); Anderson, Iver E. (Ames, IA)

    1993-09-07

    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.

  18. 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 element. Now, another use has been found: magnets. One would not expect pure carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the

  19. Inductrack magnet configuration

    DOE Patents [OSTI]

    Post, Richard Freeman

    2003-10-14

    A magnet configuration comprising a pair of Halbach arrays magnetically and structurally connected together are positioned with respect to each other so that a first component of their fields substantially cancels at a first plane between them, and a second component of their fields substantially adds at this first plane. A track of windings is located between the pair of Halbach arrays and a propulsion mechanism is provided for moving the pair of Halbach arrays along the track. When the pair of Halbach arrays move along the track and the track is not located at the first plane, a current is induced in the windings and a restoring force is exerted on the pair of Halbach arrays.

  20. Inductrack magnet configuration

    DOE Patents [OSTI]

    Post, Richard Freeman

    2003-12-16

    A magnet configuration comprising a pair of Halbach arrays magnetically and structurally connected together are positioned with respect to each other so that a first component of their fields substantially cancels at a first plane between them, and a second component of their fields substantially adds at this first plane. A track of windings is located between the pair of Halbach arrays and a propulsion mechanism is provided for moving the pair of Halbach arrays along the track. When the pair of Halbach arrays move along the track and the track is not located at the first plane, a current is induced in the windings and a restoring force is exerted on the pair of Halbach arrays.

  1. Fast superconducting magnetic field switch

    DOE Patents [OSTI]

    Goren, Y.; Mahale, N.K.

    1996-08-06

    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. 6 figs.

  2. Fast superconducting magnetic field switch

    DOE Patents [OSTI]

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

    1996-01-01

    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.

  3. Magnetic hydrogel with high coercivity

    SciTech Connect (OSTI)

    Szeri, H.; Alvero?lu, E.; Kurtan, U.; ?enel, M.; Baykal, A.

    2013-08-01

    Highlights: Polyacrylamide (PAAm) hydrogels containing magnetic BaFe{sub 12}O{sub 19} nanoparticles have been prepared. Magnetization measurements reveal that hydrogels have hard magnetic properties with high coercivity. Magnetic nanoparticles makes the gel more homogeneous and do not diffuse out of the gel during water intake. These gels are useful in applications as wastewater treatment once gels are magnetized before its usage. - Abstract: This study investigates the synthesis and characterization of polyacrylamide (PAAm) hydrogels containing magnetic BaFe{sub 12}O{sub 19} nanoparticles. Structural, electrical, and magnetic characterization of the gels have been performed with X-ray powder diffractometry, scanning electron microscopy, DC conductivity, magnetization and fluorescence spectroscopy techniques. The preparation and characterization of polyacrylamide (PAAm) hydrogels that contain 5 and 10 mg BaFe{sub 12}O{sub 19} (16 and 21 nm diameter) nanoparticles are described herein. It is seen from the fluorescence spectra that, nanoparticles surrounded to pyranine molecules so that some of pyranine molecules could not bound to the polymer strands. Electrical measurements show that presence of nanoparticles make the gel more homogeneous. Magnetization measurements reveal that hydrogels have hard magnetic properties with quite high coercivity of 4.2 kOe, which does not change with swelling. This feature makes these gels useful in applications as wastewater treatment if they are magnetized before use.

  4. Magnetic resonance apparatus

    DOE Patents [OSTI]

    Jackson, J.A.; Cooper, R.K.

    1980-10-10

    The patent consists of 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 correspondent of the field goes through a maximum. Near the maximum, the field is homogeneous over prescribed regions.

  5. Electronic Structure and Magnetism in Diluted Magnetic Semiconductors

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

    Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted magnetic semiconductors created by doping ions like Mn, Fe, or Co having a net spin into a semiconducting host

  6. Electronic Structure and Magnetism in Diluted Magnetic Semiconductors

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

    Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted magnetic semiconductors created by doping ions like Mn, Fe, or Co having a net spin into a semiconducting host

  7. Electronic Structure and Magnetism in Diluted Magnetic Semiconductors

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

    Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted magnetic semiconductors created by doping ions like Mn, Fe, or Co having a net spin into a semiconducting host

  8. Electronic Structure and Magnetism in Diluted Magnetic Semiconductors

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

    Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted magnetic semiconductors created by doping ions like Mn, Fe, or Co having a net spin into a semiconducting host

  9. Electronic Structure and Magnetism in Diluted Magnetic Semiconductors

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

    Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted magnetic semiconductors created by doping ions like Mn, Fe, or Co having a net spin into a semiconducting host

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

    DOE Patents [OSTI]

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

    2011-11-08

    An apparatus and method for continuous separation of magnetic particles from non-magnetic fluids including particular rods, magnetic fields and flow arrangements.

  11. Continuous magnetic separator and process

    DOE Patents [OSTI]

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

    2008-04-22

    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.

  12. Thin film superconductor magnetic bearings

    DOE Patents [OSTI]

    Weinberger, Bernard R. (Avon, CT)

    1995-12-26

    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.

  13. BNL Direct Wind Superconducting Magnets

    SciTech Connect (OSTI)

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

    2011-09-12

    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.

  14. Ground Magnetics | Open Energy Information

    Open Energy Info (EERE)

    Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Ground Magnetics Details Activities (25) Areas (19) Regions (0) NEPA(1) Exploration...

  15. Large Magnetization at Carbon Surfaces

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

    sensors, and data processing. Fortunately, additional research has proven that etching carbon with sulfuric acid can also make the carbon magnetic, opening the door for...

  16. Magnetic compression laser driving circuit

    DOE Patents [OSTI]

    Ball, D.G.; Birx, D.; Cook, E.G.

    1993-01-05

    A magnetic compression laser driving circuit is disclosed. The magnetic compression laser driving circuit compresses voltage pulses in the range of 1.5 microseconds at 20 kilovolts of amplitude to pulses in the range of 40 nanoseconds and 60 kilovolts of amplitude. The magnetic compression laser driving circuit includes a multi-stage magnetic switch where the last stage includes a switch having at least two turns which has larger saturated inductance with less core material so that the efficiency of the circuit and hence the laser is increased.

  17. 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 carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided

  18. 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 carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided

  19. Summary report for nanoscale magnetics

    SciTech Connect (OSTI)

    Tobin, J.G.; Waddill, G.D.; Jankowski, A.F.; Tamura, E.; Sterne, P.A.; Pappas, D.P.; Tong, S.Y.

    1993-09-23

    We have probed the electronic, geometric, and magnetic nanoscale structure of ultrathin magnetic films, both monolayers and multilayers (Fe/Cu(001), FePt, FeCoPt, UFe{sub 2}, U-S). Techniques used included the MCD (magnetic circular dichroism)-variants of of x-ray absorption, core-level photoemission, and photoelectron diffraction. Progress has been made on nanoscale structure-property relations, in part of coupling of world-class experimentation and theoretical modeling. Feasibility of investigations of 5f magnetism using bulk uranium samples also has been demonstrated.

  20. Measurements of magnetic field alignment

    SciTech Connect (OSTI)

    Kuchnir, M.; Schmidt, E.E.

    1987-11-06

    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.

  1. 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 carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided

  2. 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 carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided

  3. 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 carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided

  4. 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 carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided

  5. Magnetic compression laser driving circuit

    DOE Patents [OSTI]

    Ball, Don G. (Livermore, CA); Birx, Dan (Brentwood, CA); Cook, Edward G. (Livermore, CA)

    1993-01-01

    A magnetic compression laser driving circuit is disclosed. The magnetic compression laser driving circuit compresses voltage pulses in the range of 1.5 microseconds at 20 Kilovolts of amplitude to pulses in the range of 40 nanoseconds and 60 Kilovolts of amplitude. The magnetic compression laser driving circuit includes a multi-stage magnetic switch where the last stage includes a switch having at least two turns which has larger saturated inductance with less core material so that the efficiency of the circuit and hence the laser is increased.

  6. Multiparameter magnetic inspection system with magnetic field control and plural magnetic transducers

    DOE Patents [OSTI]

    Jiles, David C. (Ames, IA)

    1991-04-16

    A multiparameter magnetic inspection system for providing an efficient and economical way to derive a plurality of independent measurements regarding magnetic properties of the magnetic material under investigation. The plurality of transducers for a plurality of different types of measurements operatively connected to the specimen. The transducers are in turn connected to analytical circuits for converting transducer signals to meaningful measurement signals of the magnetic properties of the specimen. The measurement signals are processed and can be simultaneously communicated to a control component. The measurement signals can also be selectively plotted against one another. The control component operates the functioning of the analytical circuits and operates and controls components to impose magnetic fields of desired characteristics upon the specimen. The system therefore allows contemporaneous or simultaneous derivation of the plurality of different independent magnetic properties of the material which can then be processed to derive characteristics of the material.

  7. Multiparameter magnetic inspection system with magnetic field control and plural magnetic transducers

    DOE Patents [OSTI]

    Jiles, D.C.

    1991-04-16

    A multiparameter magnetic inspection system is disclosed for providing an efficient and economical way to derive a plurality of independent measurements regarding magnetic properties of the magnetic material under investigation. The plurality of transducers for a plurality of different types of measurements operatively connected to the specimen. The transducers are in turn connected to analytical circuits for converting transducer signals to meaningful measurement signals of the magnetic properties of the specimen. The measurement signals are processed and can be simultaneously communicated to a control component. The measurement signals can also be selectively plotted against one another. The control component operates the functioning of the analytical circuits and operates and controls components to impose magnetic fields of desired characteristics upon the specimen. The system therefore allows contemporaneous or simultaneous derivation of the plurality of different independent magnetic properties of the material which can then be processed to derive characteristics of the material. 1 figure.

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

    SciTech Connect (OSTI)

    Lamb, D. A.; Howard, T. A.; DeForest, C. E.; Parnell, C. E.; Welsch, B. T.

    2013-09-10

    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.

  9. Magnetic polarizability of the nucleon

    SciTech Connect (OSTI)

    Ragusa, S.

    1996-01-01

    We derive an expression for the magnetic polarizability of the nucleon, as related to sums of products of its electromagnetic transition moments involving the electric and magnetic dipoles and mean-square radii, as well as the electric quadrupole moment. Two sum rules emerge from the calculation. {copyright} {ital 1995 The American Physical Society.}

  10. Magnetic-field-dosimetry system

    DOE Patents [OSTI]

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

    1981-01-21

    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.

  11. Exploration of Artificial Frustrated Magnets

    SciTech Connect (OSTI)

    Samarth, Nitin; Schiffer, Peter

    2015-02-17

    This program encompasses experimental and theoretical studies of arrays of nanometer-scale magnets known as “artificial frustrated magnets”. These magnets are small and closely spaced, so that their behavior as a collective group is complex and reveals insights into how such collections of interacting objects behave as a group. In particular, the placement of the magnets is such that the interactions between them are “frustrated”, in that they compete with each other. These systems are analogs to a class of magnetic materials in which the lattice geometry frustrates interactions between individual atomic moments, and in which a wide range of novel physical phenomena have been recently observed. The advantage to studying the arrays is that they are both designable and resolvable: i.e., the experiments can control all aspects of the array geometry, and can also observe how individual elements of the arrays behave. This research program demonstrated a number of phenomena including the role of multiple collective interactions, the feasibility of using systems with their magnetism aligned perpendicular to the plane of the array, the importance of disorder in the arrays, and the possibility of using high temperatures to adjust the magnet orientations. All of these phenomena, and others explored in this program, add to the body of knowledge around collective magnetic behavior and magnetism in general. Aside from building scientific knowledge in an important technological area, with relevance to computing and memory, the program also gave critical support to the education of students working on the experiments.

  12. Magnetic Resonance Facility (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-03-01

    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.

  13. Superconducting magnetic energy storage

    SciTech Connect (OSTI)

    Hassenzahl, W.

    1988-08-01

    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.

  14. Permanent magnet multipole with adjustable strength

    DOE Patents [OSTI]

    Halbach, Klaus (Berkeley, CA)

    1985-01-01

    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.

  15. Permanent-magnet multipole with adjustable strength

    DOE Patents [OSTI]

    Halbach, K.

    1982-09-20

    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.

  16. The Butterfly Effect on Magnetic Vortices

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

    The Butterfly Effect on Magnetic Vortices The Butterfly Effect on Magnetic Vortices Print Tuesday, 20 January 2015 12:12 Miniature whirlpools of spins, also known as magnetic vortices, are currently a hot topic in magnetism research. In addition to providing insight into fundamental topological properties of materials, magnetic vortices show great potential as building blocks in advanced magnetic technologies. However, a completely reliable control over the vortex spin structure is mandatory

  17. Disorder-Induced Microscopic Magnetic Memory

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

    Disorder-Induced Microscopic Magnetic Memory Disorder-Induced Microscopic Magnetic Memory Print Wednesday, 26 October 2005 00:00 The magnetic-recording industry deliberately introduces carefully controlled disorder into its materials to obtain the desired magnetic properties. But as the density of magnetic disks climbs, the size of the magnetic domains responsible for storage must decrease, posing new challenges. Beautiful theories based on random microscopic disorder have been developed over

  18. Magnetic diagnostics for equilibrium reconstructions with eddy...

    Office of Scientific and Technical Information (OSTI)

    Magnetic diagnostics for equilibrium reconstructions with eddy currents on the lithium tokamak experimenta) Citation Details In-Document Search Title: Magnetic diagnostics for...

  19. National High Magnetic Field Laboratory moves closer

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

    researchers to carefully tune material parameters while perfectly reproducing the non-invasive magnetic field. Such high magnetic fields confine electrons to nanometer scale...

  20. Disorder-Induced Microscopic Magnetic Memory

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

    Disorder-Induced Microscopic Magnetic Memory Print The magnetic-recording industry deliberately introduces carefully controlled disorder into its materials to obtain the desired...

  1. Design Principles for Materials with Magnetic Functionality ...

    Office of Scientific and Technical Information (OSTI)

    Design Principles for Materials with Magnetic Functionality Citation Details In-Document Search Title: Design Principles for Materials with Magnetic Functionality This report ...

  2. Design Principles for Materials with Magnetic Functionality ...

    Office of Scientific and Technical Information (OSTI)

    Design Principles for Materials with Magnetic Functionality Citation Details In-Document Search Title: Design Principles for Materials with Magnetic Functionality You are ...

  3. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their...

  4. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Direct Imaging of Asymmetric Magnetization Reversal Print Wednesday, 28 September 2005 00:00 The phenomenon of exchange bias has...

  5. Category:Ground Magnetics | Open Energy Information

    Open Energy Info (EERE)

    Ground Magnetics Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermalpower.jpg Looking for the Ground Magnetics page? For detailed information on Ground...

  6. Regenerator for Magnetic Refrigerants - Energy Innovation Portal

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

    Description Magnetic refrigeration is being investigated as an alternative to conventional ... These materials may thus have improved properties for magnetic refrigeration. As part of ...

  7. Magnetic Pair Spectrometer Studies of Electromagnetic Transitions...

    Office of Scientific and Technical Information (OSTI)

    Warburton, E. K. PHYSICS; BRANCHING RATIO; CARBON 13; CARBON 14; DECAY; DEUTERON BEAMS; ELECTRIC CHARGES; ENERGY; ENERGY LEVELS; ERRORS; LIFETIME; MAGNETIC FIELDS; MAGNETIC...

  8. Magnetic Pair Spectrometer Studies of Electromagnetic Transitions...

    Office of Scientific and Technical Information (OSTI)

    English Subject: PHYSICS; BRANCHING RATIO; CARBON 13; CARBON 14; DECAY; DEUTERON BEAMS; ELECTRIC CHARGES; ENERGY; ENERGY LEVELS; ERRORS; LIFETIME; MAGNETIC FIELDS; MAGNETIC...

  9. COLLOQUIUM: Laboratory Study of Magnetic Reconnection: Recent...

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

    reconnection is a phenomenon of nature in which magnetic field lines change their topology in plasma and convert magnetic energy to particles by acceleration and heating. It is...

  10. 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

    2013-10-08

    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.

  11. Periodic permanent magnet focused klystron

    DOE Patents [OSTI]

    Ferguson, Patrick; Read, Michael; Ives, R Lawrence

    2015-04-21

    A periodic permanent magnet (PPM) klystron has beam transport structures and RF cavity structures, each of which has permanent magnets placed substantially equidistant from a beam tunnel formed about the central axis, and which are also outside the extent of a cooling chamber. The RF cavity sections also have permanent magnets which are placed substantially equidistant from the beam tunnel, but which include an RF cavity coupling to the beam tunnel for enhancement of RF carried by an electron beam in the beam tunnel.

  12. Magnetic cellulose-derivative structures

    DOE Patents [OSTI]

    Walsh, M.A.; Morris, R.S.

    1986-09-16

    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 sorption agents can be incorporated during the manufacture of the structure. 3 figs.

  13. Magnetic microbes: Bacterial magnetite biomineralization

    SciTech Connect (OSTI)

    Prozorov, Tanya

    2015-09-14

    Magnetotactic bacteria are a diverse group of prokaryotes with the ability to orient and migrate along the magnetic field lines in search for a preferred oxygen concentration in chemically stratified water columns and sediments. These microorganisms produce magnetosomes, the intracellular nanometer-sized magnetic crystals surrounded by a phospholipid bilayer membrane, typically organized in chains. Magnetosomes have nearly perfect crystal structures with narrow size distribution and species-specific morphologies, leading to well-defined magnetic properties. As a result, the magnetite biomineralization in these organisms is of fundamental interest to diverse disciplines, from biotechnology to astrobiology. As a result, this article highlights recent advances in the understanding of the bacterial magnetite biomineralization.

  14. Magnetic cellulose-derivative structures

    DOE Patents [OSTI]

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

    1986-09-16

    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.

  15. Nuclear magnetic resonance contrast agents

    DOE Patents [OSTI]

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

    1997-12-30

    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.

  16. Nuclear magnetic resonance contrast agents

    DOE Patents [OSTI]

    Smith, Paul H.; Brainard, James R.; Jarvinen, Gordon D.; Ryan, Robert R.

    1997-01-01

    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.

  17. Improved superconducting magnet wire

    DOE Patents [OSTI]

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

    1983-08-16

    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.

  18. Magnetic-compression/magnetized-target fusion (MAGO/MTF): A marriage of inertial and magnetic confinement

    SciTech Connect (OSTI)

    Lindemuth, I.R.; Ekdahl, C.A.; Kirkpatrick, R.C.

    1996-12-31

    Intermediate between magnetic confinement (MFE) and inertial confinement (ICF) in time and density scales is an area of research now known in the US as magnetized target fusion (MTF) and in Russian as MAGO (MAGnitnoye Obzhatiye--magnetic compression). MAGO/MTF uses a magnetic field and preheated, wall-confined plasma fusion fuel within an implodable fusion target. The magnetic field suppresses thermal conduction losses in the fuel during the target implosion and hydrodynamic compression heating process. In contrast to direct, hydrodynamic compression of initially ambient-temperature fuel (i.e., ICF), MAGO/MTF involves two steps: (a) formation of a warm (e.g., 100 eV or higher), magnetized (e.g., 100 kG) plasma within a fusion target prior to implosion; (b) subsequent quasi-adiabatic compression by an imploding pusher, of which a magnetically driven imploding liner is one example. In this paper, the authors present ongoing activities and potential future activities in this relatively unexplored area of controlled thermonuclear fusion.

  19. Large Magnetization at Carbon Surfaces

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

    x-ray spectroscopy at ALS Beamline 4.0.2 to study the magnetism of proton-irradiated graphite surfaces in order to understand the effects of hydrogen (i.e. protons) on the...

  20. Magnetically stimulated fluid flow patterns

    SciTech Connect (OSTI)

    Martin, Jim; Solis, Kyle

    2014-03-06

    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.

  1. Magnetically stimulated fluid flow patterns

    ScienceCinema (OSTI)

    Martin, Jim; Solis, Kyle

    2014-08-06

    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.

  2. Lensless Imaging of Magnetic Nanostructures

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

    of x-rays used. This promising method can be used at any coherent light source, including modern x-ray free-electron lasers, where ultrashort pulses would freeze-frame magnetic...

  3. Magnet Girder Assembly and Installation

    ScienceCinema (OSTI)

    None

    2013-07-17

    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.

  4. Lensless Imaging of Magnetic Nanostructures

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

    Gambino, S. Mangin, S. Roy, and P. Fischer, "X-ray diffraction microscopy of magnetic structures," Phys. Rev. Lett. 107, 033904 (2011). ALS Science Highlight 244 ALSNews Vol. 329...

  5. Lensless Imaging of Magnetic Nanostructures

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

    I. McNulty, R. Gambino, S. Mangin, S. Roy, and P. Fischer, "X-ray diffraction microscopy of magnetic structures," Phys. Rev. Lett. 107, 033904 (2011). ALS Science Highlight 244...

  6. Magnetically focused liquid drop radiator

    DOE Patents [OSTI]

    Botts, Thomas E. (Fairfax, VA); Powell, James R. (Shoreham, NY); Lenard, Roger (Redondo Beach, CA)

    1986-01-01

    A magnetically focused liquid drop radiator for application in rejecting rgy from a spacecraft, characterized by a magnetizable liquid or slurry disposed in operative relationship within the liquid droplet generator and its fluid delivery system, in combination with magnetic means disposed in operative relationship around a liquid droplet collector of the LDR. The magnetic means are effective to focus streams of droplets directed from the generator toward the collector, thereby to assure that essentially all of the droplets are directed into the collector, even though some of the streams may be misdirected as they leave the generator. The magnetic focusing means is also effective to suppress splashing of liquid when the droplets impinge on the collector.

  7. Magnetically focused liquid drop radiator

    DOE Patents [OSTI]

    Botts, T.E.; Powell, J.R.; Lenard, R.

    1984-12-10

    A magnetically focused liquid drop radiator for application in rejecting energy from a spacecraft, characterized by a magnetizable liquid or slurry disposed in operative relationship within the liquid droplet generator and its fluid delivery system, in combination with magnetic means disposed in operative relationship around a liquid droplet collector of the LDR. The magnetic means are effective to focus streams of droplets directed from the generator toward the collector, thereby to assure that essentially all of the droplets are directed into the collector, even though some of the streams may be misdirected as they leave the generator. The magnetic focusing means is also effective to suppress splashing of liquid when the droplets impinge on the collector.

  8. Large Magnetization at Carbon Surfaces

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

    Now, researchers are using x-ray spectroscopy at ALS Beamline 4.0.2 to study the magnetism of proton-irradiated graphite surfaces in order to understand the effects of...

  9. 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)

    1988-01-01

    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.

  10. Magnetically insulated transmission line oscillator

    DOE Patents [OSTI]

    Bacon, L.D.; Ballard, W.P.; Clark, M.C.; Marder, B.M.

    1987-05-19

    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 are 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. 11 figs.

  11. Compact magnetic energy storage module

    DOE Patents [OSTI]

    Prueitt, M.L.

    1994-12-20

    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.

  12. Condensed Matter and Magnet Science

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

    CMMS Condensed Matter and Magnet Science The group has a distinguished history of applying cutting-edge condensed matter physics research and high magnetic field science to mission-relevant materials challenges as well as fundamental investigations of emergent physical phenomena. Contact Us Group Leader (acting) Chuck Mielke Email Deputy Group Leader (acting) Leonardo Civale Email Deputy Group Leader (acting) Ross McDonald Email NHMFL-PFF Director Chuck Mielke Email Deputy NHMFL-PFF Director

  13. Compact magnetic energy storage module

    DOE Patents [OSTI]

    Prueitt, Melvin L.

    1994-01-01

    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.

  14. Superconducting magnet development in Japan

    SciTech Connect (OSTI)

    Yasukochi, K.

    1983-05-01

    The present state of R and D works on the superconducting magnet and its applications in Japan are presented. On electrical rotating machines, 30 MVA superconducting synchronous rotary condenser (Mitsubishi and Fuji) and 50 MVA generator are under construction. Two ways of ship propulsion by superconducting magnets are developing. A superconducting magnetically levitated and linear motor propelled train ''MAGLEV'' was developed by the Japan National Railways (JNR). The superconducting magnet development for fusion is the most active field in Japan. The Cluster Test program has been demonstrated on a 10 T Nb/sub 3/Sn coil and the first coil of Large Coil Task in IEA collaboration has been constructed and the domestic test was completed in JAERI. These works are for the development of toroidal coils of the next generation tokamak machine. R and D works on superconducting ohmic heating coil are in progress in JAERI and ETL. The latter group has constructed 3.8 MJ pulsed coil. A high ramp rate of changing field in pulsed magnet, 200 T/s, has been tested successfully. High Energy Physics Laboratory (KEK) are conducting active works. The superconducting ..mu.. meson channel and ..pi.. meson channel have been constructed and are operating successfully. KEK has also a project of big accelerator named ''TRISTAN'', which is similar to ISABELLE project of BNL. Superconducting synchrotron magnets are developed for this project. The development of superconducting three thin wall solenoid has been started. One of them, CDF, is progressing under USA-Japan collaboration.

  15. Optical sensor of magnetic fields

    DOE Patents [OSTI]

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

    1986-03-25

    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.

  16. MICE Spectrometer Magnet System Progress

    SciTech Connect (OSTI)

    Green, Michael A.; Virostek, Steve P.

    2007-08-27

    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.

  17. Steering magnet design for a limited space

    SciTech Connect (OSTI)

    Okamura,M.; Fite, J.; Lodestro, V.; Raparia, D.; Ritter, J.

    2009-05-04

    We compare two extreme designs of steering magnets. The first one is a very thin steering magnet design which occupies only 6 mm in length and can be additionally installed as needed. The other is realized by applying extra coil windings to a quadrupole magnet and does not consume any length. The properties and the features of these steering magnets are discussed.

  18. Ames Lab 101: Ultrafast Magnetic Switching

    ScienceCinema (OSTI)

    Jigang Wang

    2013-06-05

    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.

  19. Signal enhancement using a switchable magnetic trap

    DOE Patents [OSTI]

    Beer, Neil Reginald (Pleasanton, CA)

    2012-05-29

    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.

  20. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron microscopy at the ALS to directly image the magnetic structure of an exchange-biased film,

  1. Disorder-Induced Microscopic Magnetic Memory

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

    Disorder-Induced Microscopic Magnetic Memory Print The magnetic-recording industry deliberately introduces carefully controlled disorder into its materials to obtain the desired magnetic properties. But as the density of magnetic disks climbs, the size of the magnetic domains responsible for storage must decrease, posing new challenges. Beautiful theories based on random microscopic disorder have been developed over the past ten years. To directly compare these theories with precise experiments,

  2. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron microscopy at the ALS to directly image the magnetic structure of an exchange-biased film,

  3. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron microscopy at the ALS to directly image the magnetic structure of an exchange-biased film,

  4. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron microscopy at the ALS to directly image the magnetic structure of an exchange-biased film,

  5. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron microscopy at the ALS to directly image the magnetic structure of an exchange-biased film,

  6. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Direct Imaging of Asymmetric Magnetization Reversal Print Wednesday, 28 September 2005 00:00 The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron

  7. Disorder-Induced Microscopic Magnetic Memory

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

    Disorder-Induced Microscopic Magnetic Memory Print The magnetic-recording industry deliberately introduces carefully controlled disorder into its materials to obtain the desired magnetic properties. But as the density of magnetic disks climbs, the size of the magnetic domains responsible for storage must decrease, posing new challenges. Beautiful theories based on random microscopic disorder have been developed over the past ten years. To directly compare these theories with precise experiments,

  8. Disorder-Induced Microscopic Magnetic Memory

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

    Disorder-Induced Microscopic Magnetic Memory Print The magnetic-recording industry deliberately introduces carefully controlled disorder into its materials to obtain the desired magnetic properties. But as the density of magnetic disks climbs, the size of the magnetic domains responsible for storage must decrease, posing new challenges. Beautiful theories based on random microscopic disorder have been developed over the past ten years. To directly compare these theories with precise experiments,

  9. Disorder-Induced Microscopic Magnetic Memory

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

    Disorder-Induced Microscopic Magnetic Memory Print The magnetic-recording industry deliberately introduces carefully controlled disorder into its materials to obtain the desired magnetic properties. But as the density of magnetic disks climbs, the size of the magnetic domains responsible for storage must decrease, posing new challenges. Beautiful theories based on random microscopic disorder have been developed over the past ten years. To directly compare these theories with precise experiments,

  10. Disorder-Induced Microscopic Magnetic Memory

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

    Disorder-Induced Microscopic Magnetic Memory Print The magnetic-recording industry deliberately introduces carefully controlled disorder into its materials to obtain the desired magnetic properties. But as the density of magnetic disks climbs, the size of the magnetic domains responsible for storage must decrease, posing new challenges. Beautiful theories based on random microscopic disorder have been developed over the past ten years. To directly compare these theories with precise experiments,

  11. Magnetic reconnection | Princeton Plasma Physics Lab

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

    Magnetic reconnection Subscribe to RSS - Magnetic reconnection Magnetic reconnection (henceforth called "reconnection") refers to the breaking and reconnecting of oppositely directed magnetic field lines in a plasma. In the process, magnetic field energy is converted to plasma kinetic and thermal energy. PPPL team wins 80 million processor hours on nation's fastest supercomputer The U.S Department of Energy (DOE) has awarded a total of 80 million processor hours on the fastest

  12. Local stress engineering of magnetic anisotropy in soft magnetic thin films

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect Local stress engineering of magnetic anisotropy in soft magnetic thin films Citation Details In-Document Search Title: Local stress engineering of magnetic anisotropy in soft magnetic thin films The magnetic anisotropy of amorphous thin films was modified laterally by masked ion irradiation without alteration of the intrinsic magnetic properties. The changes were introduced by local ion implantation in a protection layer, causing additional stress-induced

  13. Dynamic control of spin states in interacting magnetic elements

    DOE Patents [OSTI]

    Jain, Shikha; Novosad, Valentyn

    2014-10-07

    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.

  14. Magnetic microbes: Bacterial magnetite biomineralization

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

    Prozorov, Tanya

    2015-09-14

    Magnetotactic bacteria are a diverse group of prokaryotes with the ability to orient and migrate along the magnetic field lines in search for a preferred oxygen concentration in chemically stratified water columns and sediments. These microorganisms produce magnetosomes, the intracellular nanometer-sized magnetic crystals surrounded by a phospholipid bilayer membrane, typically organized in chains. Magnetosomes have nearly perfect crystal structures with narrow size distribution and species-specific morphologies, leading to well-defined magnetic properties. As a result, the magnetite biomineralization in these organisms is of fundamental interest to diverse disciplines, from biotechnology to astrobiology. As a result, this article highlights recent advances inmore » the understanding of the bacterial magnetite biomineralization.« less

  15. Hyperon polarization and magnetic moments

    SciTech Connect (OSTI)

    Lach, J.

    1993-12-01

    Inclusively produced hyperons with significant polarization were first observed at Fermilab about seventeen years ago. This and subsequent experiments showed that {Lambda}{degree} were produced polarized while {bar {Lambda}}{degree} had no polarization in the same kinematical region. This set the stage for many experiments which showed that most hyperons are produced polarized. Recent Fermilab experiments have showed that this phenomena is even more complex and theoretical understanding is still lacking. Nevertheless polarized hyperon beams have been an extremely useful experimental tool in measuring hyperon magnetic moments. Recently, magnetic moment precession of channeled particles in bent crystals has been observed. This opens the possibility of measuring the magnetic moments of charmed baryons.

  16. High performance magnetic bearing systems using high temperature superconductors

    DOE Patents [OSTI]

    Abboud, R.G.

    1998-05-05

    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.

  17. High performance magnetic bearing systems using high temperature superconductors

    DOE Patents [OSTI]

    Abboud, Robert G. (Barrington Hills, IL)

    1998-01-01

    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.

  18. Wheel-type magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, J.A.

    1983-10-11

    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.

  19. Wheel-type magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, John A. (Los Alamos, NM)

    1983-01-01

    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.

  20. Wheel-type magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, J.A.

    1982-01-20

    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.

  1. Laminated magnet field coil sheath

    DOE Patents [OSTI]

    Skaritka, J.R.

    1987-05-15

    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.

  2. Resonant and non-resonant magnetic scattering

    SciTech Connect (OSTI)

    McWhan, D.B.; Hastings, J.B.; Kao, C.C.; Siddons, D.P.

    1991-12-31

    The tunability and the polarization of synchrotron radiation open upon new possibilities for the study of magnetism. Studies on magnetic materials performed at the National Synchrotron Light Source are reviewed, and thy fall into four areas: structure, evolution of magnetic order, separation of L and S, and resonance effects. In the vicinity of atomic absorption edges, the Faraday effect, magnetic circular dichroism, and resonant magnetic scattering are all related resonance effects which measure the spin polarized density of states. The production and analysis of polarized beams are discussed in the context of the study of magnetism with synchrotron radiation.

  3. Resonant and non-resonant magnetic scattering

    SciTech Connect (OSTI)

    McWhan, D.B.; Hastings, J.B.; Kao, C.C.; Siddons, D.P.

    1991-01-01

    The tunability and the polarization of synchrotron radiation open upon new possibilities for the study of magnetism. Studies on magnetic materials performed at the National Synchrotron Light Source are reviewed, and thy fall into four areas: structure, evolution of magnetic order, separation of L and S, and resonance effects. In the vicinity of atomic absorption edges, the Faraday effect, magnetic circular dichroism, and resonant magnetic scattering are all related resonance effects which measure the spin polarized density of states. The production and analysis of polarized beams are discussed in the context of the study of magnetism with synchrotron radiation.

  4. Magnetic refrigeration apparatus with heat pipes

    DOE Patents [OSTI]

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

    1985-10-25

    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.

  5. Magnetic refrigeration apparatus with heat pipes

    DOE Patents [OSTI]

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

    1987-01-01

    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.

  6. Making permanent magnets more powerful and less expensive | The...

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

    Making permanent magnets more powerful and less expensive Today's high-tech and clean energy capabilities are extremely reliant on powerful permanent magnets. Permanent magnets...

  7. Not All Nanodisk Magnetic Vortices Are Created Equally

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

    Not All Nanodisk Magnetic Vortices Are Created Equally Print Magnetic vortices - hurricanes of magnetism only a few atoms across - have generated intense interest in the high-tech...

  8. Design and Synthesis of Novel Diluted Magnetic Semiconductors...

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

    Design and Synthesis of Novel Diluted Magnetic Semiconductors Diluted magnetic semiconductors (DMSs) are semiconductors doped with small amounts of magnetic active transition...

  9. Structural modulations and magnetic properties of off-stoichiometric...

    Office of Scientific and Technical Information (OSTI)

    magnetic shape memory alloys Prev Next Title: Structural modulations and magnetic properties of off-stoichiometric Ni-Mn-Ga magnetic shape memory alloys Authors: ...

  10. Magnetic levitation system for moving objects - Energy Innovation...

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

    Abstract: Repelling magnetic forces are produced by the interaction of a flux-concentrated magnetic field (produced by permanent magnets or electromagnets) with an...

  11. Magnetic dipole interactions in crystals

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

    Johnston, David

    2016-01-13

    The influence of magnetic dipole interactions (MDIs) on the magnetic properties of local-moment Heisenberg spin systems is investigated. A general formulation is presented for calculating the eigenvalues λ and eigenvectors μ ˆ of the MDI tensor of the magnetic dipoles in a line (one dimension, 1D), within a circle (2D) or a sphere (3D) of radius r surrounding a given moment μ → i for given magnetic propagation vectors k for collinear and coplanar noncollinear magnetic structures on both Bravais and non-Bravais spin lattices. Results are calculated for collinear ordering on 1D chains, 2D square and simple-hexagonal (triangular) Bravais lattices,more » 2D honeycomb and kagomé non-Bravais lattices, and 3D cubic Bravais lattices. The λ and μ ˆ values are compared with previously reported results. Calculations for collinear ordering on 3D simple tetragonal, body-centered tetragonal, and stacked triangular and honeycomb lattices are presented for c/a ratios from 0.5 to 3 in both graphical and tabular form to facilitate comparison of experimentally determined easy axes of ordering on these Bravais lattices with the predictions for MDIs. Comparisons with the easy axes measured for several illustrative collinear antiferromagnets (AFMs) are given. The calculations are extended to the cycloidal noncollinear 120 ° AFM ordering on the triangular lattice where λ is found to be the same as for collinear AFM ordering with the same k. The angular orientation of the ordered moments in the noncollinear coplanar AFM structure of GdB 4 with a distorted stacked 3D Shastry-Sutherland spin-lattice geometry is calculated and found to be in disagreement with experimental observations, indicating the presence of another source of anisotropy. Similar calculations for the undistorted 2D and stacked 3D Shastry-Sutherland lattices are reported. The thermodynamics of dipolar magnets are calculated using the Weiss molecular field theory for quantum spins, including the magnetic transition temperature T m and the ordered moment, magnetic heat capacity, and anisotropic magnetic susceptibility χ versus temperature T . The anisotropic Weiss temperature θ p in the Curie-Weiss law for T>T m is calculated. A quantitative study of the competition between FM and AFM ordering on cubic Bravais lattices versus the demagnetization factor in the absence of FM domain effects is presented. The contributions of Heisenberg exchange interactions and of the MDIs to T m and to θ p are found to be additive, which simplifies analysis of experimental data. Some properties in the magnetically-ordered state versus T are presented, including the ordered moment and magnetic heat capacity and, for AFMs, the dipolar anisotropy of the free energy and the perpendicular critical field. The anisotropic χ for dipolar AFMs is calculated both above and below the Néel temperature T N and the results are illustrated for a simple tetragonal lattice with c/a>1, c/a=1 (cubic), and c/a<1 , where a change in sign of the χ anisotropy is found at c/a=1 . Finally, following the early work of Keffer [Phys. Rev. 87, 608 (1952)], the dipolar anisotropy of χ above T N =69 K of the prototype collinear Heisenberg-exchange-coupled tetragonal compound MnF 2 is calculated and found to be in excellent agreement with experimental single-crystal literature data above 130 K, where the smoothly increasing deviation of the experimental data from the theory on cooling from 130 K to T N is deduced to arise from dynamic short-range collinear c -axis AFM ordering in this temperature range driven by the exchange interactions.« less

  12. Bioinspired synthesis of magnetic nanoparticles

    SciTech Connect (OSTI)

    David, Anand

    2009-05-26

    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.

  13. 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)

    2010-12-28

    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.

  14. Magnetically coupled system for mixing

    DOE Patents [OSTI]

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

    2014-04-01

    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.

  15. Magnetically coupled system for mixing

    DOE Patents [OSTI]

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

    2015-09-22

    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.

  16. Magnetic nano-particles | The Ames Laboratory

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

    Magnetic nano-particles The student will be involved in assembling CoFe2O4 nano-particles onto Si wafers for further studies by X-ray magnetic circular dichroism (XMCD) that will...

  17. Platinum dendritic nanoparticles with magnetic behavior

    SciTech Connect (OSTI)

    Li, Wenxian; Sun, Ziqi; Nevirkovets, Ivan P.; Dou, Shi-Xue; Tian, Dongliang

    2014-07-21

    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.

  18. Direct Imaging of Asymmetric Magnetization Reversal

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

    material like iron is itself a tiny magnet represented by a magnetic moment. If the atomic moments are pointing in random directions, they cancel each other out. So, to bring...

  19. Magnetism at Nanoscale | The Ames Laboratory

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

    will be able to sense the extremely weak magnetic fields of just a handful of electrons with the spatial resolution of about 10 nanometers. "We want to determine magnetic...

  20. Generic magnetic fusion reactor cost assessment

    SciTech Connect (OSTI)

    Sheffield, J.

    1984-01-01

    A generic D-T burning magnetic fusion reactor model shows that within the constraints set by generic limitations it is possible for magnetic fusion to be a competitive source of electricity in the 21st century.

  1. How Bacteria Make Magnets | The Ames Laboratory

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

    How Bacteria Make Magnets For a number of animals, including birds, fish and mammals, there is evidence that magnets are used for orientation. However, little is known about how...

  2. Magnetic bearing element with adjustable stiffness

    DOE Patents [OSTI]

    Post, Richard F

    2013-11-12

    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.

  3. Ames Lab 101: Rare-Earth Magnets

    ScienceCinema (OSTI)

    McCallum, Bill

    2012-08-29

    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.

  4. Reversing the Circulation of Magnetic Vortices

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

    the Circulation of Magnetic Vortices Print Wednesday, 31 July 2013 00:00 In magnetic media, information is stored in binary form-one or zero, depending on which way the...

  5. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in...

  6. Bipolar pulse field for magnetic refrigeration

    DOE Patents [OSTI]

    Lubell, M.S.

    1994-10-25

    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.

  7. Bipolar pulse field for magnetic refrigeration

    DOE Patents [OSTI]

    Lubell, Martin S. (Oak Ridge, TN)

    1994-01-01

    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.

  8. Magnetic switch for reactor control rod. [LMFBR

    DOE Patents [OSTI]

    Germer, J.H.

    1982-09-30

    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.

  9. Reversing the Circulation of Magnetic Vortices

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

    very stable and form readily in soft magnetic materials of the sort useful for magnetic random-access memory (MRAM) devices. Interestingly, the formation of such vortices was at...

  10. Chemical synthesis, characterizations and magnetic properties...

    Office of Scientific and Technical Information (OSTI)

    PHYSICAL AND ANALYTICAL CHEMISTRY; 36 MATERIALS SCIENCE; 77 NANOSCIENCE AND NANOTECHNOLOGY; ALLOYS; BCC LATTICES; COERCIVE FORCE; CRYSTALS; LATTICE PARAMETERS; MAGNETIC...

  11. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Reversing the Circulation of Magnetic Vortices Print Wednesday, 31 July 2013 00:00 In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny

  12. Hidden Rotational Symmetries in Magnetic Domain Patterns

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

    Hidden Rotational Symmetries in Magnetic Domain Patterns Hidden Rotational Symmetries in Magnetic Domain Patterns Print Wednesday, 27 June 2012 00:00 Magnetic thin films have complicated domain patterns that may or may not repeat with each cycle through a hysteresis loop. A magnetic thin film with perpendicular anisotropy, such as that used in computer hard drives, for example, commonly exhibits labyrinthine domain patterns. These patterns are disordered over a macroscopic length scale, and

  13. Rotating copper plasmoid in external magnetic field

    SciTech Connect (OSTI)

    Pandey, Pramod K.; Thareja, Raj K.

    2013-02-15

    Effect of nonuniform magnetic field on the expanding copper plasmoid in helium and argon gases using optical emission spectroscopy and fast imaging is presented. We report a peculiar oscillatory rotation of plasmoid in magnetic field and argon ambient. The temporal variation and appearance of the dip in the electron temperature show a direct evidence of the threading and expulsion of the magnetic field lines from the plasmoid. Rayleigh Taylor instability produced at the interface separating magnetic field and plasma is discussed.

  14. Magnetic-cusp, cathodic-arc source

    DOE Patents [OSTI]

    Falabella, Steven (Livermore, CA)

    1995-01-01

    A magnetic-cusp for a cathodic-arc source wherein the arc is confined to the desired cathode surface, provides a current path for electrons from the cathode to the anode, and utilizes electric and magnetic fields to guide ions from the cathode to a point of use, such as substrates to be coated. The magnetic-cusp insures arc stability by an easy magnetic path from anode to cathode, while the straight-through arrangement leads to high ion transmission.

  15. Ground Magnetics (Nannini, 1986) | Open Energy Information

    Open Energy Info (EERE)

    to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Magnetics (Nannini, 1986) Exploration Activity Details Location Unspecified Exploration...

  16. Magnetic multipole redirector of moving plasmas

    DOE Patents [OSTI]

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

    1999-01-01

    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.

  17. Primordial magnetic field limits from cosmological data

    SciTech Connect (OSTI)

    Kahniashvili, Tina [McWilliams Center for Cosmology and Department of Physics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213 (United States); Department of Physics, Laurentian University, Ramsey Lake Road, Sudbury, Ontario P3E 2C (Canada); Abastumani Astrophysical Observatory, Ilia State University, 2A Kazbegi Ave, Tbilisi, GE-0160 (Georgia); Tevzadze, Alexander G. [Abastumani Astrophysical Observatory, Ilia State University, 2A Kazbegi Ave, Tbilisi, GE-0160 (Georgia); Faculty of Exact and Natural Sciences, Tbilisi State University, 1 Chavchavadze Avenue, Tbilisi, GE-0128 (Georgia); Sethi, Shiv K. [McWilliams Center for Cosmology and Department of Physics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213 (United States); Raman Research Institute, Sadashivanagar, Bangalore 560080 (India); Pandey, Kanhaiya [Raman Research Institute, Sadashivanagar, Bangalore 560080 (India); Ratra, Bharat [Department of Physics, Kansas State University, 116 Cardwell Hall, Manhattan, Kansas 66506 (United States)

    2010-10-15

    We study limits on a primordial magnetic field arising from cosmological data, including that from big bang nucleosynthesis, cosmic microwave background polarization plane Faraday rotation limits, and large-scale structure formation. We show that the physically relevant quantity is the value of the effective magnetic field, and limits on it are independent of how the magnetic field was generated.

  18. Electronic structure, magnetic properties, and magnetostructural

    Office of Scientific and Technical Information (OSTI)

    transformations in rare earth dialuminides (Journal Article) | SciTech Connect SciTech Connect Search Results Journal Article: Electronic structure, magnetic properties, and magnetostructural transformations in rare earth dialuminides Citation Details In-Document Search Title: Electronic structure, magnetic properties, and magnetostructural transformations in rare earth dialuminides We report electronic structure, magnetic properties, and magnetostructural transformations of selected rare

  19. Electronic structure, magnetic properties, and magnetostructural

    Office of Scientific and Technical Information (OSTI)

    transformations in rare earth dialuminides (Journal Article) | SciTech Connect SciTech Connect Search Results Journal Article: Electronic structure, magnetic properties, and magnetostructural transformations in rare earth dialuminides Citation Details In-Document Search Title: Electronic structure, magnetic properties, and magnetostructural transformations in rare earth dialuminides We report electronic structure, magnetic properties, and magnetostructural transformations of selected rare

  20. Tiny magnets could work in sensors, information encoding

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

    Tiny magnets could work in sensors, information encoding Tiny magnets could work in sensors, information encoding Scientists have realized a nanoscale, artificial magnet by arranging an array of magnetic nano-islands along a geometry that is not found in natural magnets. November 1, 2015 Tiny magnets could work in sensors, information encoding Researchers have created a nanoscale, artificial magnet by arranging an array of magnetic nano-islands along a geometry that is not found in natural

  1. Deconvolution of mixed magnetism in multilayer graphene

    SciTech Connect (OSTI)

    Swain, Akshaya Kumar; Bahadur, Dhirendra

    2014-06-16

    Magnetic properties of graphite modified at the edges by KCl and exfoliated graphite in the form of twisted multilayered graphene (<4 layers) are analyzed to understand the evolution of magnetic behavior in the absence of any magnetic impurities. The mixed magnetism in multilayer graphene is deconvoluted using Low field-high field hysteresis loops at different temperatures. In addition to temperature and the applied magnetic field, the density of edge state spins and the interaction between them decides the nature of the magnetic state. By virtue of magnetometry and electron spin resonance studies, we demonstrate that ferromagnetism is intrinsic and is due to the interactions among various paramagnetic centers. The strength of these magnetic correlations can be controlled by modifying the structure.

  2. Superconducting magnetic shielding apparatus and method

    DOE Patents [OSTI]

    Clem, J.R.

    1982-07-09

    Disclosed is a method and apparatus for providing magnetic shielding around a working volume. The apparatus includes a hollow elongated superconducting shell or cylinder having an elongated low magnetic pinning central portion, and two high magnetic pinning end regions. Transition portions of varying magnetic pinning properties are interposed between the central and end portions. The apparatus further includes a solenoid substantially coextensive with and overlying the superconducting cylinder, so as to be magnetically coupled therewith. The method includes the steps passing a longitudinally directed current through the superconducting cylinder so as to depin magnetic reservoirs trapped in the cylinder. Next, a circumferentially directed current is passed through the cylinder, while a longitudinally directed current is maintained. Depinned magnetic reservoirs are moved to the end portions of the cylinder, where they are trapped.

  3. Magnetic switch for reactor control rod

    DOE Patents [OSTI]

    Germer, John H. (San Jose, CA)

    1986-01-01

    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.

  4. Magnetic vector field tag and seal

    DOE Patents [OSTI]

    Johnston, Roger G.; Garcia, Anthony R.

    2004-08-31

    One or more magnets are placed in a container (preferably on objects inside the container) and the magnetic field strength and vector direction are measured with a magnetometer from at least one location near the container to provide the container with a magnetic vector field tag and seal. The location(s) of the magnetometer relative to the container are also noted. If the position of any magnet inside the container changes, then the measured vector fields at the these locations also change, indicating that the tag has been removed, the seal has broken, and therefore that the container and objects inside may have been tampered with. A hollow wheel with magnets inside may also provide a similar magnetic vector field tag and seal. As the wheel turns, the magnets tumble randomly inside, removing the tag and breaking the seal.

  5. Superconducting magnetic shielding apparatus and method

    DOE Patents [OSTI]

    Clem, John R. (Ames, IA); Clem, John R. (Ames, IA)

    1983-01-01

    Disclosed is a method and apparatus for providing magnetic shielding around a working volume. The apparatus includes a hollow elongated superconducting shell or cylinder having an elongated low magnetic pinning central portion, and two high magnetic pinning end regions. Transition portions of varying magnetic pinning properties are interposed between the central and end portions. The apparatus further includes a solenoid substantially coextensive with and overlying the superconducting cylinder, so as to be magnetically coupled therewith. The method includes the steps passing a longitudinally directed current through the superconducting cylinder so as to depin magnetic reservoirs trapped in the cylinder. Next, a circumferentially directed current is passed through the cylinder, while a longitudinally directed current is maintained. Depinned magnetic reservoirs are moved to the end portions of the cylinder, where they are trapped.

  6. Superconducting magnetic shielding apparatus and method

    DOE Patents [OSTI]

    Clem, J.R.; Clem, J.R.

    1983-10-11

    Disclosed are a method and apparatus for providing magnetic shielding around a working volume. The apparatus includes a hollow elongated superconducting shell or cylinder having an elongated low magnetic pinning central portion, and two high magnetic pinning end regions. Transition portions of varying magnetic pinning properties are interposed between the central and end portions. The apparatus further includes a solenoid substantially coextensive with and overlying the superconducting cylinder, so as to be magnetically coupled therewith. The method includes the steps passing a longitudinally directed current through the superconducting cylinder so as to depin magnetic reservoirs trapped in the cylinder. Next, a circumferentially directed current is passed through the cylinder, while a longitudinally directed current is maintained. Depinned magnetic reservoirs are moved to the end portions of the cylinder, where they are trapped. 5 figs.

  7. Hermetically sealed superconducting magnet motor

    DOE Patents [OSTI]

    DeVault, Robert C. (Knoxville, TN); McConnell, Benjamin W. (Knoxville, TN); Phillips, Benjamin A. (Benton Harbor, MI)

    1996-01-01

    A hermetically sealed superconducting magnet motor includes a rotor separated from a stator by either a radial gap, an axial gap, or a combined axial and radial gap. Dual conically shaped stators are used in one embodiment to levitate a disc-shaped rotor made of superconducting material within a conduit for moving cryogenic fluid. As the rotor is caused to rotate when the field stator is energized, the fluid is pumped through the conduit.

  8. Magnetic instability of Kondo insulators

    SciTech Connect (OSTI)

    Wang, Ziqiang [Los Alamos National Lab., NM (United States)]|[Boston Univ., MA (United States). Dept. of Physics; Li, Xiao-Ping [Rutgers--the State Univ., Piscataway, NJ (United States). Serin Physics Lab.; Lee, Dung-Hai [International Business Machines Corp., Yorktown Heights, NY (United States). Thomas J. Watson Research Center

    1993-09-01

    We review a number of experiments on isoelectronic, isostructural ternary compounds CeTSn (T=Ni,Pd,Sn) and alloys CeNi{sub 1-x}(Pd,Pt){sub x}Sn, and propose a finite temperature phase diagram describing the evolution of a Kondo insulator to an antiferromagnetic Kondo state with decreasing hybridization or Kondo coupling. We then provide microscopic justifications for the phase diagram by analyzing the magnetic properties of the symmetric Kondo lattice model in two dimensions.

  9. Magnetic transit-time flowmeter

    DOE Patents [OSTI]

    Forster, George A.

    1976-07-06

    The flow rate of a conducting fluid in a stream is determined by disposing two permanent-magnet flowmeters in the stream, one downstream of the other. Flow of the conducting fluid causes the generation of both d-c and a-c electrical signals, the a-c comprising flow noise. Measurement of the time delay between similarities in the a-c signals by cross-correlation methods provides a measure of the rate of flow of the fluid.

  10. Hermetically sealed superconducting magnet motor

    DOE Patents [OSTI]

    DeVault, R.C.; McConnell, B.W.; Phillips, B.A.

    1996-07-02

    A hermetically sealed superconducting magnet motor includes a rotor separated from a stator by either a radial gap, an axial gap, or a combined axial and radial gap. Dual conically shaped stators are used in one embodiment to levitate a disc-shaped rotor made of superconducting material within a conduit for moving cryogenic fluid. As the rotor is caused to rotate when the field stator is energized, the fluid is pumped through the conduit. 6 figs.

  11. Formation of magnetic discontinuities through viscous relaxation

    SciTech Connect (OSTI)

    Kumar, Sanjay; Bhattacharyya, R.; Smolarkiewicz, P. K.

    2014-05-15

    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.

  12. Magnetic design and measurement of nonlinear multipole magnets for the APT beam expander system

    SciTech Connect (OSTI)

    Barlow, D.B.; Shafer, R.E.; Martinez, R.P.; Walstrom, P.L.; Kahn, S.; Jain, A.; Wanderer, P.

    1997-10-01

    Two prototype nonlinear multipole magnets have been designed for use in the 800-MeV beam test of the APT beam-expansion concept at LANSCE. The iron-dominated magnets each consist of three independent coils, two for producing a predominantly octupole field with a tunable duodecapole component, and one for canceling the residual quadrupole field. Two such magnets, one for shaping each transverse plane, are required to produce a rectangular, uniform beam current density distribution with sharp edges on the APT target. This report will describe the magnetic design of these magnets, along with field measurements, and a comparison to the magnetic design.

  13. Toroidal constant-tension superconducting magnetic energy storage units

    DOE Patents [OSTI]

    Herring, J. Stephen (Idaho Falls, ID)

    1992-01-01

    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.

  14. Practical method using superposition of individual magnetic fields for

    Office of Scientific and Technical Information (OSTI)

    initial arrangement of undulator magnets (Journal Article) | SciTech Connect Practical method using superposition of individual magnetic fields for initial arrangement of undulator magnets Citation Details In-Document Search Title: Practical method using superposition of individual magnetic fields for initial arrangement of undulator magnets We have developed a practical method for determining an excellent initial arrangement of magnetic arrays for a pure-magnet Halbach-type undulator. In

  15. Physical Attraction: The Mysteries of Magnetism

    SciTech Connect (OSTI)

    Stohr, Joachim

    2004-12-14

    Most people have intuitive associations with the word 'magnetism' based on everyday life: refrigerator magnets, the compass, north and south poles, or someone's 'magnetic personality'. Few people, however, realize how complicated the phenomenon really is, how much research still deals with the topic today, and how much it penetrates our modern industrialized world - from electricity, wireless communication at the speed of light to magnetic sensors in cars and data storage in computers. Stohr's lecture will provide a glimpse at the magic and science behind magnetism: its long history, scientific breakthroughs in its understanding, and its use in our modern society. In the process Stohr will show how research at SSRL/SLAC is addressing some of the forefront issues in magnetism research and technology today.

  16. Thermomagnetic burn control for magnetic fusion reactor

    DOE Patents [OSTI]

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

    1982-01-01

    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.

  17. Thermomagnetic burn control for magnetic fusion reactor

    DOE Patents [OSTI]

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

    1980-07-01

    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.

  18. Superconducting flat tape cable magnet

    DOE Patents [OSTI]

    Takayasu, Makoto

    2015-08-11

    A method for winding a coil magnet with the stacked tape cables, and a coil so wound. The winding process is controlled and various shape coils can be wound by twisting about the longitudinal axis of the cable and bending following the easy bend direction during winding, so that sharp local bending can be obtained by adjusting the twist pitch. Stack-tape cable is twisted while being wound, instead of being twisted in a straight configuration and then wound. In certain embodiments, the straight length should be half of the cable twist-pitch or a multiple of it.

  19. Magnetic monopoles: a status report

    SciTech Connect (OSTI)

    Carrigan, R.A. Jr.; Trower, W.P.

    1983-03-01

    A solitary, uncorroborated Stanford candidate event is the only evidence that magnetic monpoles derives from Dirac's assertion that monopoles could explain charge quantization and the 't Hooft-Polyakov demonstration that monopoles are an inevitable consequence of many gauge theories currently being used to unify the electroweak (photon-lepton) and nuclear (quark) interactions. The monopole abundance implied by the Stanford event is in clear contradiction to bounds on their number from astronomical data. Fortunately, the already considerable and expanding arsenal of detection techniques are being fashioned to experimentally test the many open questions surrounding monopoles.

  20. Electric/magnetic field sensor

    DOE Patents [OSTI]

    Schill, Jr., Robert A. (Henderson, NV); Popek, Marc [Las Vegas, NV

    2009-01-27

    A UNLV novel electric/magnetic dot sensor includes a loop of conductor having two ends to the loop, a first end and a second end; the first end of the conductor seamlessly secured to a first conductor within a first sheath; the second end of the conductor seamlessly secured to a second conductor within a second sheath; and the first sheath and the second sheath positioned adjacent each other. The UNLV novel sensor can be made by removing outer layers in a segment of coaxial cable, leaving a continuous link of essentially uncovered conductor between two coaxial cable legs.

  1. Plutonium less mysterious with nuclear magnetic resonance

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

    Plutonium less mysterious with nuclear magnetic resonance Plutonium less mysterious with nuclear magnetic resonance For more than 50 years, chemists and physicists have been searching for the plutonium-239 magnetic resonance signal. May 21, 2012 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new

  2. Hidden Rotational Symmetries in Magnetic Domain Patterns

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

    Hidden Rotational Symmetries in Magnetic Domain Patterns Print Magnetic thin films have complicated domain patterns that may or may not repeat with each cycle through a hysteresis loop. A magnetic thin film with perpendicular anisotropy, such as that used in computer hard drives, for example, commonly exhibits labyrinthine domain patterns. These patterns are disordered over a macroscopic length scale, and intuitively we do not expect to observe any symmetry in such systems. Scientists at the

  3. Hidden Rotational Symmetries in Magnetic Domain Patterns

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

    Hidden Rotational Symmetries in Magnetic Domain Patterns Print Magnetic thin films have complicated domain patterns that may or may not repeat with each cycle through a hysteresis loop. A magnetic thin film with perpendicular anisotropy, such as that used in computer hard drives, for example, commonly exhibits labyrinthine domain patterns. These patterns are disordered over a macroscopic length scale, and intuitively we do not expect to observe any symmetry in such systems. Scientists at the

  4. Hidden Rotational Symmetries in Magnetic Domain Patterns

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

    Hidden Rotational Symmetries in Magnetic Domain Patterns Print Magnetic thin films have complicated domain patterns that may or may not repeat with each cycle through a hysteresis loop. A magnetic thin film with perpendicular anisotropy, such as that used in computer hard drives, for example, commonly exhibits labyrinthine domain patterns. These patterns are disordered over a macroscopic length scale, and intuitively we do not expect to observe any symmetry in such systems. Scientists at the

  5. Hidden Rotational Symmetries in Magnetic Domain Patterns

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

    Hidden Rotational Symmetries in Magnetic Domain Patterns Print Magnetic thin films have complicated domain patterns that may or may not repeat with each cycle through a hysteresis loop. A magnetic thin film with perpendicular anisotropy, such as that used in computer hard drives, for example, commonly exhibits labyrinthine domain patterns. These patterns are disordered over a macroscopic length scale, and intuitively we do not expect to observe any symmetry in such systems. Scientists at the

  6. Hidden Rotational Symmetries in Magnetic Domain Patterns

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

    Hidden Rotational Symmetries in Magnetic Domain Patterns Print Magnetic thin films have complicated domain patterns that may or may not repeat with each cycle through a hysteresis loop. A magnetic thin film with perpendicular anisotropy, such as that used in computer hard drives, for example, commonly exhibits labyrinthine domain patterns. These patterns are disordered over a macroscopic length scale, and intuitively we do not expect to observe any symmetry in such systems. Scientists at the

  7. Magnetic microbes: Bacterial magnetite biomineralization (Journal Article)

    Office of Scientific and Technical Information (OSTI)

    | SciTech Connect Magnetic microbes: Bacterial magnetite biomineralization Citation Details In-Document Search This content will become publicly available on September 14, 2016 Title: Magnetic microbes: Bacterial magnetite biomineralization Magnetotactic bacteria are a diverse group of prokaryotes with the ability to orient and migrate along the magnetic field lines in search for a preferred oxygen concentration in chemically stratified water columns and sediments. These microorganisms

  8. Hidden Rotational Symmetries in Magnetic Domain Patterns

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

    Hidden Rotational Symmetries in Magnetic Domain Patterns Print Magnetic thin films have complicated domain patterns that may or may not repeat with each cycle through a hysteresis loop. A magnetic thin film with perpendicular anisotropy, such as that used in computer hard drives, for example, commonly exhibits labyrinthine domain patterns. These patterns are disordered over a macroscopic length scale, and intuitively we do not expect to observe any symmetry in such systems. Scientists at the

  9. Hidden Rotational Symmetries in Magnetic Domain Patterns

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

    Hidden Rotational Symmetries in Magnetic Domain Patterns Print Magnetic thin films have complicated domain patterns that may or may not repeat with each cycle through a hysteresis loop. A magnetic thin film with perpendicular anisotropy, such as that used in computer hard drives, for example, commonly exhibits labyrinthine domain patterns. These patterns are disordered over a macroscopic length scale, and intuitively we do not expect to observe any symmetry in such systems. Scientists at the

  10. Hidden Rotational Symmetries in Magnetic Domain Patterns

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

    Hidden Rotational Symmetries in Magnetic Domain Patterns Print Magnetic thin films have complicated domain patterns that may or may not repeat with each cycle through a hysteresis loop. A magnetic thin film with perpendicular anisotropy, such as that used in computer hard drives, for example, commonly exhibits labyrinthine domain patterns. These patterns are disordered over a macroscopic length scale, and intuitively we do not expect to observe any symmetry in such systems. Scientists at the

  11. Electron Temperature Structures Associated With Magnetic Tearing

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

    Structures Associated With Magnetic Tearing Modes in the Madison Symmetric Torus By Hillary Dianne Stephens A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy (Physics) at the UNIVERSITY OF WISCONSIN - MADISON 2010 i Abstract Tearing mode induced magnetic islands have a significant impact on the thermal char- acteristics of magnetically confined plasmas such as those in the reversed-field pinch. Using a state-of-the-art Thomson scattering

  12. Edward Purcell and Nuclear Magnetic Resonance (NMR)

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

    Edward Mills Purcell and Nuclear Magnetic Resonance (NMR) Resources with Additional Information Edward M. Purcell was awarded the 1952 Nobel Prize in Physics for his "development of new methods for nuclear magnetic precision measurements and discoveries in connection therewith". Purcell first observed nuclear magnetic resonance (NMR) in 1945 while working at the Massachusetts Institute of Technology (MIT) Radiation Laboratory in an after-hours experiment. Edward M. Purcell Courtesy

  13. Permanent magnet edge-field quadrupole

    DOE Patents [OSTI]

    Tatchyn, Roman O. (Mountain View, CA)

    1997-01-01

    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.

  14. Permanent magnet edge-field quadrupole

    DOE Patents [OSTI]

    Tatchyn, R.O.

    1997-01-21

    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. 10 figs.

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

    SciTech Connect (OSTI)

    2012-01-01

    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 corecoupling 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.

  16. EFFECTS OF MAGNETIC FIELDS ON THE PROPAGATION OF NUCLEAR FLAMES IN MAGNETIC WHITE DWARFS

    SciTech Connect (OSTI)

    Kutsuna, Masamichi; Shigeyama, Toshikazu [Research Center for the Early Universe, Graduate School of Science, University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2012-04-10

    We investigate the effects of the magnetic field on the propagation of laminar flames of nuclear reactions taking place in white dwarfs with masses close to the Chandrasekhar limit. We calculate the velocities of laminar flames parallel and perpendicular to uniform magnetic fields as eigenvalues of steady solutions for magnetic hydrodynamical equations. As a result, we find that even when the magnetic pressure does not dominate the entire pressure it is possible for the magnetic field to suppress the flame propagation through the thermal conduction. Above the critical magnetic field, the flame velocity decreases with increasing magnetic field strength as v {approx} B{sup -1}. In media with densities of 10{sup 7}, 10{sup 8}, and 10{sup 9} g cm{sup -3}, the critical magnetic fields are orders of {approx}10{sup 10}, 10{sup 11}, and 10{sup 12} G, respectively.

  17. Batch fabrication of precision miniature permanent magnets

    DOE Patents [OSTI]

    Christenson, Todd R. (Albuquerque, NM); Garino, Terry J. (Albuquerque, NM); Venturini, Eugene L. (Albuquerque, NM)

    2002-01-01

    A new class of processes for fabrication of precision miniature rare earth permanent magnets is disclosed. Such magnets typically have sizes in the range 0.1 to 10 millimeters, and dimensional tolerances as small as one micron. Very large magnetic fields can be produced by such magnets, lending to their potential application in MEMS and related electromechanical applications, and in miniature millimeter-wave vacuum tubes. This abstract contains simplifications, and is supplied only for purposes of searching, not to limit or alter the scope or meaning of any claims herein.

  18. Hidden Rotational Symmetries in Magnetic Domain Patterns

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

    A magnetic thin film with perpendicular anisotropy, such as that used in computer hard drives, for example, commonly exhibits labyrinthine domain patterns. These patterns are...

  19. Hidden Rotational Symmetries in Magnetic Domain Patterns

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

    and magnetization history. Left: A typical speckle pattern from the CoPd multilayer. Color bar at bottom indicates relative intensity. The rotational symmetry of a scattering...

  20. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  1. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  2. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  3. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  4. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  5. The Butterfly Effect on Magnetic Vortices

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

    in advanced magnetic technologies. However, a completely reliable control over the vortex spin structure is ... can significantly determine the final outcome of a process. ...

  6. Electronic & Magnetic Materials & Devices Capabilities | Argonne...

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

    Electronic & Magnetic Materials & Devices Capabilities Synthesis Colloidal chemistry and self-assembly techniques Complex oxide film synthesis via molecular beam epitaxy (DCA R450...

  7. Magnetic-cusp, cathodic-arc source

    DOE Patents [OSTI]

    Falabella, S.

    1995-11-21

    A magnetic-cusp for a cathodic-arc source wherein the arc is confined to the desired cathode surface, provides a current path for electrons from the cathode to the anode, and utilizes electric and magnetic fields to guide ions from the cathode to a point of use, such as substrates to be coated. The magnetic-cusp insures arc stability by an easy magnetic path from anode to cathode, while the straight-through arrangement leads to high ion transmission. 3 figs.

  8. Edward Purcell and Nuclear Magnetic Resonance (NMR)

    Office of Scientific and Technical Information (OSTI)

    Edward Mills Purcell and Nuclear Magnetic Resonance (NMR) Resources with Additional Information Edward M. Purcell was awarded the 1952 Nobel Prize in Physics for his "development...

  9. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  10. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  11. Quantitative Modeling of High Temperature Magnetization Dynamics

    SciTech Connect (OSTI)

    Zhang, Shufeng

    2009-03-01

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

  12. Disorder-Induced Microscopic Magnetic Memory

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

    point for future theories. The Persistence of Memory Magnets are not just for refrigerator doors-they are of paramount importance in today's digital information age. In the...

  13. Neutrons find "missing" magnetism of plutonium

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

    Neutrons find "missing" magnetism of plutonium Alumni Link: Opportunities, News and Resources for Former Employees Latest Issue:September 2015 all issues All Issues submit...

  14. Reversing the Circulation of Magnetic Vortices

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

    No other method can provide similarly comprehensive information about the fastest dynamics of magnetic states on the nanoscale. These instruments are unique and serve the whole...

  15. Aqua Magnetics Inc | Open Energy Information

    Open Energy Info (EERE)

    Zip: 32937 Sector: Ocean Product: Manufactures patented system that converts ocean wave energy into electric power. References: Aqua-Magnetics Inc1 This article is a stub. You...

  16. Practical Considerations in Realizing a Magnetic Centrifugal...

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

    The Magnetic Centrifugal Mass Filter concept represents a variation on the plasma centrifuge, with applications that are particularly promising for high-throughput separation of...

  17. 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)

    2014-03-24

    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.

  18. EMITTANCE COMPENSATION FOR MAGNETIZED BEAMS

    SciTech Connect (OSTI)

    KEWISCH,J.; CHANG, X.

    2007-06-25

    Emittance compensation is a well established technique for minimizing the emittance of an electron beam from a RF photo-cathode gun. Longitudinal slices of a bunch have a small emittance, but due to the longitudinal charge distribution of the bunch and time dependent RF fields they are not focused in the same way, so that the direction of their phase ellipses diverges in phase space and the projected emittance is much larger. Emittance compensation reverses the divergence. At the location where the slopes of the phase ellipses coincide the beam is accelerated, so that the space charge forces are reduced. A recipe for emittance compensation is given in. For magnetized beams (where the angular momentum is non-zero) such emittance compensation is not sufficient because variations in the slice radius lead to variations in the angular speed and therefore to an increase of emittance in the rotating game. We describe a method and tools for a compensation that includes the beam magnetization.

  19. Strain-assisted current-induced magnetization reversal in magnetic tunnel

    Office of Scientific and Technical Information (OSTI)

    junctions: A micromagnetic study with phase-field microelasticity (Journal Article) | SciTech Connect Strain-assisted current-induced magnetization reversal in magnetic tunnel junctions: A micromagnetic study with phase-field microelasticity Citation Details In-Document Search Title: Strain-assisted current-induced magnetization reversal in magnetic tunnel junctions: A micromagnetic study with phase-field microelasticity Effect of substrate misfit strain on current-induced in-plane

  20. 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

    2013-09-03

    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.

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

    DOE Patents [OSTI]

    Hull, J.R.

    1997-08-05

    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.

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

    DOE Patents [OSTI]

    Hull, J.R.

    1996-10-08

    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.

  3. Apparatus and method for handling magnetic particles in a fluid

    DOE Patents [OSTI]

    Holman, David A. (Richland, WA); Grate, Jay W. (West Richland, WA); Bruckner-Lea, Cynthia J. (Richland, WA)

    2000-01-01

    The present invention is an apparatus and method for handling magnetic particles suspended in a fluid, relying upon the known features of a magnetic flux conductor that is permeable thereby permitting the magnetic particles and fluid to flow therethrough; and a controllable magnetic field for the handling. The present invention is an improvement wherein the magnetic flux conductor is a monolithic porous foam.

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

    DOE Patents [OSTI]

    Hull, John R. (Hinsdale, IL)

    1996-01-01

    A method and apparatus 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.

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

    DOE Patents [OSTI]

    Hull, John R. (Hinsdale, IL)

    1997-01-01

    A method and apparatus 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.

  6. DC-based magnetic field controller

    DOE Patents [OSTI]

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

    1994-05-31

    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.

  7. DC-based magnetic field controller

    DOE Patents [OSTI]

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

    1994-01-01

    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.

  8. Magnetic positioner having a single moving part

    DOE Patents [OSTI]

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

    1999-01-01

    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.

  9. Frontiers for Laboratory Research of Magnetic Reconnection

    SciTech Connect (OSTI)

    Ji, Hantao; Guo, Fan

    2015-07-16

    Magnetic reconnection occcurs throughout heliophysical and astrophysical plasmas as well as in laboratory fusion plasmas. Two broad categories of reconnection models exist: collisional MHD and collisionless kinetic. Eight major questions with respect to magnetic connection are set down, and past and future devices for studying them in the laboratory are described. Results of some computerized simulations are compared with experiments.

  10. Vacuum magnetic fields with dense flux surfaces

    SciTech Connect (OSTI)

    Cary, J R

    1982-05-01

    A procedure is given for eliminating resonances and stochasticity in nonaxisymmetric vacuum toroidal magnetic field. The results of this procedure are tested by the surface of section method. It is found that one can obtain magnetic fields with increased rotational transform and decreased island structure while retaining basically the same winding law.

  11. 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)

    2011-08-23

    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.

  12. Ternary Dy-Er-Al magnetic refrigerants

    DOE Patents [OSTI]

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

    1995-07-25

    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.

  13. Ternary Dy-Er-Al magnetic refrigerants

    DOE Patents [OSTI]

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

    1995-07-25

    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.

  14. Ion Rings for Magnetic Fusion

    SciTech Connect (OSTI)

    Greenly, John, B.

    2005-07-31

    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.

  15. Magnetic levitation system for moving objects

    DOE Patents [OSTI]

    Post, Richard F. (Walnut Creek, CA)

    1998-01-01

    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.

  16. Magnetic levitation system for moving objects

    DOE Patents [OSTI]

    Post, R.F.

    1998-03-03

    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. Passive magnetic bearing for a horizontal shaft

    DOE Patents [OSTI]

    Post, Richard F.

    2003-12-02

    A passive magnetic bearing is composed of a levitation element and a restorative element. The levitation element is composed of a pair of stationary arcuate ferromagnetic segments located within an annular radial-field magnet array. The magnet array is attached to the inner circumference of a hollow shaft end. An attractive force between the arcuate segments and the magnet array acts vertically to levitate the shaft, and also in a horizontal transverse direction to center the shaft. The restorative element is comprised of an annular Halbach array of magnets and a stationary annular circuit array located within the Halbach array. The Halbach array is attached to the inner circumference of the hollow shaft end. A repulsive force between the Halbach array and the circuit array increases inversely to the radial space between them, and thus acts to restore the shaft to its equilibrium axis of rotation when it is displaced therefrom.

  18. Tiny Particles with Big Magnetic Power | Argonne National Laboratory

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

    "Magnetic nanofibers" are special not only for their inherent properties as individual magnets, but also for their ability to be manipulated and deposited precisely to form novel materials. PDF icon tiny_magnetic_particles

  19. Magnetic separator having high rate of field change capability

    SciTech Connect (OSTI)

    Tillotson, J.A.; Crowe, K.M.

    1990-12-18

    This paper describes a combination of a large magnet for classifying magnetic particles from a passing fluid stream of magnetic and nonmagnetic particles. The large magnet including a central canister having a diameter exceeding 60-inches. It comprises: first and second manifolds for communicating; magnetic coils; a magnetic field; a power supply; first solid state rectifier circuit; second solid state rectifier circuit; first power supply drive means; and, second power supply drive means.

  20. Method and apparatus for control of a magnetic structure

    DOE Patents [OSTI]

    Challenger, Michael P. (Bothell, WA); Valla, Arthur S. (Bothell, WA)

    1996-06-18

    A method and apparatus for independently adjusting the spacing between opposing magnet arrays in charged particle based light sources. Adjustment mechanisms between each of the magnet arrays and the supporting structure allow the gap between the two magnet arrays to be independently adjusted. In addition, spherical bearings in the linkages to the magnet arrays permit the transverse angular orientation of the magnet arrays to also be adjusted. The opposing magnet arrays can be supported above the ground by the structural support.

  1. Whirlpools on the Nanoscale Could Multiply Magnetic Memory

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

    Whirlpools on the Nanoscale Could Multiply Magnetic Memory Whirlpools on the Nanoscale Could Multiply Magnetic Memory Print Tuesday, 21 May 2013 00:00 Research at the Advanced Light Source may lead to four-bit magnetic cells housed on nanoscale metal disks, instead of the two-bit magnetic domains of standard magnetic memories. In magnetic vortices, parallel electron spins point either clockwise or counterclockwise, while in their crowded centers the spins point either down or up. "From the

  2. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  3. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  4. Early Career: Emergent Atomic and Magnetic Structures | The Ames Laboratory

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

    Early Career: Emergent Atomic and Magnetic Structures Research Personnel Updates Publications They're Alive Read More Caught in the Act! Read More Previous Pause Next Characterization Determining the nature of the macromolecule-mediated magnetic nanoparticle formation: Uniform magnetic nanoparticles with large magnetic moment and controlled magnetic anisotropy have important technological applications from data storage and quantum computing to catalysis and drug delivery. The Emergent Magnetic

  5. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  6. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  7. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  8. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  9. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  10. Magnetic Correlations in the Quasi-Two-Dimensional Semiconducting...

    Office of Scientific and Technical Information (OSTI)

    dramatically. Establishing the nature of the bulk material's magnetism is necessary for understanding the thin-film magnetic behavior and the material's possible applications. ...

  11. Probing nanoscale behavior of magnetic materials with soft x...

    Office of Scientific and Technical Information (OSTI)

    Probing nanoscale behavior of magnetic materials with soft x-ray spectromicroscopy Citation Details In-Document Search Title: Probing nanoscale behavior of magnetic materials with...

  12. Magnetic Field Line Tracing Calculations for Conceptual PFC Design...

    Office of Scientific and Technical Information (OSTI)

    Conference: Magnetic Field Line Tracing Calculations for Conceptual PFC Design in the National Compact Stellarator Experiment Citation Details In-Document Search Title: Magnetic...

  13. Whirlpools on the Nanoscale Could Multiply Magnetic Memory

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

    Whirlpools on the Nanoscale Could Multiply Magnetic Memory Whirlpools on the Nanoscale Could Multiply Magnetic Memory Print Tuesday, 21 May 2013 00:00 Research at the Advanced...

  14. Surface Morphology and Magnetic Anisotropy (Conference) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Conference: Surface Morphology and Magnetic Anisotropy Citation Details In-Document Search Title: Surface Morphology and Magnetic Anisotropy Authors: Lukaszew, R.A. ; Zhang, Z. ;...

  15. Highly Charged Ions in Magnetic Fusion Plasmas: Research Opportunities...

    Office of Scientific and Technical Information (OSTI)

    Highly Charged Ions in Magnetic Fusion Plasmas: Research Opportunities and Diagnostic Necessities Citation Details In-Document Search Title: Highly Charged Ions in Magnetic Fusion ...

  16. Scientists discuss progress toward magnetic fusion energy at...

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

    Scientists discuss progress toward magnetic fusion energy at 2013 AAAS annual meeting ... Scientists participating in the worldwide effort to develop magnetic fusion energy for ...

  17. Pecharsky talks magnetic refrigeration with Forbes | The Ames...

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

    Pecharsky talks magnetic refrigeration with Forbes In a May 6 article, Forbes contributor Hillary Brueck writes about the race to develop magnetic refrigeration and interviewed...

  18. Not All Nanodisk Magnetic Vortices Are Created Equally

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

    Are Created Equally Print Wednesday, 29 August 2012 00:00 Magnetic vortices - hurricanes of magnetism only a few atoms across - have generated intense interest in the...

  19. Tiny Particles with Big Magnetic Power | Argonne National Laboratory

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

    Argonne scientists have developed a new material known as magnetic nanofibers to create more efficient magnets. PDF icon Nano Sheet_tiny particles

  20. Allan Cormack, Computerized Axial Tomography (CAT), and Magnetic...

    Office of Scientific and Technical Information (OSTI)

    Allan M. Cormack, Computerized Axial Tomography (CAT) and Magnetic Resonance Imaging (MRI) Resources with Additional Information magnetic resonance imaging system Computed axial...

  1. Magneto-Optic Biosensor Using Bio-Functionalized Magnetic Nanoparticle...

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

    Magneto-Optic Biosensor Using Bio-Functionalized Magnetic Nanoparticles Technology available for licensing: A long-range interaction between magnetic nanoparticles and an external...

  2. Effect of resonant magnetic perturbations on three dimensional...

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

    Effect of resonant magnetic perturbations on three dimensional equilibria in the Madison Symmetric Torus reversed-field ... mode and produces a rotating magnetic perturbation ...

  3. Driven Skyrmions and Dynamical Transitions in Chiral Magnets...

    Office of Scientific and Technical Information (OSTI)

    Driven Skyrmions and Dynamical Transitions in Chiral Magnets Citation Details In-Document Search Title: Driven Skyrmions and Dynamical Transitions in Chiral Magnets Authors: Lin, ...

  4. Low Temperature Crystal Structure and Magnetic Properties of...

    Office of Scientific and Technical Information (OSTI)

    Low Temperature Crystal Structure and Magnetic Properties of RAl2 Citation Details In-Document Search Title: Low Temperature Crystal Structure and Magnetic Properties of RAl2 Low ...

  5. A Magnetically Controlled Plasma Source Inventor Yevgeny Raitses...

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

    A Magnetically Controlled Plasma Source Inventor Yevgeny Raitses This invention is a multipurpose and highly versatile plasma source that uses applied electric and magnetic fields...

  6. "Permanent Magnet Generator-like AC Current Drive for Torroidal...

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

    Fusion Devices" Inventor..--.. Ali Zolfaghari The scheme is similar to a permanent magnet generator. Large strong permanent magnets placed toroidally on the outside of a torus are...

  7. Novel Flux Coupling Machine without Permanent Magnets - U Machine...

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

    Magnets Novel Flux Coupling Machine without Permanent Magnets Vehicle Technologies Office Merit Review 2014: Alternative High-Performance Motors with Non-Rare Earth Materials...

  8. Magnetic nanohole superlattices (Patent) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Patent: Magnetic nanohole superlattices Citation Details In-Document Search Title: Magnetic nanohole superlattices You are accessing a document from the Department of Energy's...

  9. Topics: Uncovering the physics of magnetic self-organization...

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

    Uncovering the physics of magnetic self-organization and links to astrophysics UW Madison Madison Symmetric Torus Topics: Uncovering the physics of magnetic self-organization and ...

  10. Recycling Magnets from the Factory Floor | The Ames Laboratory

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

    Energy Innovation Hub led by the Ames Laboratory, recovers valuable rare-earth magnetic material from manufacturing waste and creates useful magnets out of it. Ames Laboratory...

  11. Jiangxi Jinli Permanent Magnet Technology Co Ltd | Open Energy...

    Open Energy Info (EERE)

    Jinli Permanent Magnet Technology Co Ltd Jump to: navigation, search Name: Jiangxi Jinli Permanent Magnet Technology Co Ltd Place: Ganzhou, Jiangxi Province, China Sector: Wind...

  12. Hengdian Group DMEGC Magnetics Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Hengdian Group DMEGC Magnetics Co Ltd Jump to: navigation, search Name: Hengdian Group DMEGC Magnetics Co Ltd Place: Dongyang, Zhejiang Province, China Zip: 322118 Product:...

  13. CMI Unique Facility: Thermal Analysis in High Magnetic Fields...

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

    analysis components to be compatible with high magnetic fields and radio frequency induction heating. Thermal analysis of materials at high temperatures and high magnetic fields...

  14. Structural, magnetic, and electronic properties of vanadium-substitute...

    Office of Scientific and Technical Information (OSTI)

    Structural, magnetic, and electronic properties of vanadium-substituted nickel chromium sulfide Citation Details In-Document Search Title: Structural, magnetic, and electronic ...

  15. Dynamic, self-assembled aggregates of magnetized, millimeter...

    Office of Scientific and Technical Information (OSTI)

    magnetized disks floating on a liquid-air interface, and rotating under the influence of a rotating external magnetic field. Spinning of the disks results in...

  16. Proximity-induced magnetism in transition-metal substituted graphene...

    Office of Scientific and Technical Information (OSTI)

    Proximity-induced magnetism in transition-metal substituted graphene Citation Details In-Document Search Title: Proximity-induced magnetism in transition-metal substituted graphene ...

  17. Port hole perturbations to the magnetic field in MST

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

    where the magnetic field is determined primarily by magnet windings, this is straightforward and need only be performed each time major system parameters are changed....

  18. Brookhaven-Built Magnet Will Catch Subatomic Debris

    ScienceCinema (OSTI)

    Peter Wanderer

    2013-07-22

    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

  19. Magnetic Vortex Core Reversal by Low-Field Excitations

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

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

  20. Magnetic flowmeter for electrically conductive liquid

    DOE Patents [OSTI]

    Skladzien, Stanley B. (Elmhurst, IL); Raue, Donald J. (Naperville, IL)

    1982-01-01

    A magnetic flowmeter includes first and second tube sections each having ls of non-magnetic material. The first tube is suitably connected to a process for passing a flow of an electrically conductive fluid to be measured. The second tube is established as a reference containing a still medium and is maintained at the same temperature as the first tube. A rotatable magnet assembly is disposed between the two tubes with at least two magnets attached to radially extending arms from a central shaft. Each magnet includes an air gap suitably sized to pass astraddle the diameter along a portion of the length of each of the two tubes. The magnets are provided in matched pairs spaced 180.degree. apart such that signals will be simultaneously generated in signal leads attached to each of the two tubes. By comparing the signals from the two tubes and varying the rotating speed of the magnet assembly until the signals are equal, or attain a maximum, the flow velocity of the fluid within the first tube can be determined. Through temperature monitoring and appropriate heaters, the two tubes are maintained at the same temperature.

  1. Magnets for Muon 6D Cooling Channels

    SciTech Connect (OSTI)

    Johnson, Rolland; Flanagan, Gene

    2014-09-10

    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.

  2. Magnetic flowmeter for electrically conductive liquid

    DOE Patents [OSTI]

    Skladzien, S.B.; Raue, D.J.

    1980-08-18

    A magnetic flowmeter includes first and second tube sections each having walls of non-magnetic material. The first tube is suitably connected to a process for passing a flow of an electrically conductive fluid to be measured. The second tube is established as a reference containing a still medium and is maintained at the same temperature as the first tube. A rotatable magnet assembly is disposed between the two tubes with at least two magnets attached to radially extending arms from a central shaft. Each magnet includes an air gap suitably sized to pass astraddle the diameter along a portion of the length of each of the two tubes. Two magnets are provided in matched pairs spaced 180/sup 0/ apart such that signals will be simultaneously generated in signal leads attached to each of the two tubes. By comparing the signals from the two tubes and varying the rotating speed of the magnet assembly until the signals are equal, or attain a maximum, the flow velocity of the fluid within the first tube can be determined. Through temperature monitoring and appropriate heaters, the two tubes are maintained at the same temperature.

  3. 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)

    1999-01-01

    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.

  4. Nonlinear simulations to optimize magnetic nanoparticle hyperthermia

    SciTech Connect (OSTI)

    Reeves, Daniel B. Weaver, John B.

    2014-03-10

    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 Nel 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.

  5. Local thermodynamics of a magnetized, anisotropic plasma

    SciTech Connect (OSTI)

    Hazeltine, R. D.; Mahajan, S. M.; Morrison, P. J.

    2013-02-15

    An expression for the internal energy of a fluid element in a weakly coupled, magnetized, anisotropic plasma is derived from first principles. The result is a function of entropy, particle density and magnetic field, and as such plays the role of a thermodynamic potential: it determines in principle all thermodynamic properties of the fluid element. In particular it provides equations of state for the magnetized plasma. The derivation uses familiar fluid equations, a few elements of kinetic theory, the MHD version of Faraday's law, and certain familiar stability and regularity conditions.

  6. Driven reconnection in magnetic fusion experiments

    SciTech Connect (OSTI)

    Fitzpatrick, R.

    1995-11-01

    Error fields (i.e. small non-axisymmetric perturbations of the magnetic field due to coil misalignments, etc.) are a fact of life in magnetic fusion experiments. What effects do error fields have on plasma confinement? How can any detrimental effects be alleviated? These, and other, questions are explored in detail in this lecture using simple resistive magnetohydrodynamic (resistance MHD) arguments. Although the lecture concentrates on one particular type of magnetic fusion device, namely, the tokamak, the analysis is fairly general and could also be used to examine the effects of error fields on other types of device (e.g. Reversed Field Pinches, Stellerators, etc.).

  7. Magnetized liner inertial fusion (MagLIF)

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

    Magnetized liner inertial fusion (MagLIF) [1] is an inertial confinement fusion (ICF) scheme using cylindrical compression of magnetized, preheated DT gas. A 10 - 30 T axial magnetic field reduces electron thermal conductivity allowing near-adiabatic compression at implosion velocities of order 100 km/s, much lower than the 300 km/s or more required for conventional ICF. Preheating to at least 100 eV ensures that keV temperatures are reached with a convergence ratio no greater than 30. The

  8. Nonlinear plasma wave in magnetized plasmas

    SciTech Connect (OSTI)

    Bulanov, Sergei V.; Prokhorov Institute of General Physics, Russian Academy of Sciences, Moscow 119991; Moscow Institute of Physics and Technology, Dolgoprudny, Moscow region 141700 ; Esirkepov, Timur Zh.; Kando, Masaki; Koga, James K.; Hosokai, Tomonao; Zhidkov, Alexei G.; Japan Science and Technology Agency, CREST, 2-1, Yamadaoka, Suita, Osaka 565-0871 ; Kodama, Ryosuke; Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871

    2013-08-15

    Nonlinear axisymmetric cylindrical plasma oscillations in magnetized collisionless plasmas are a model for the electron fluid collapse on the axis behind an ultrashort relativisically intense laser pulse exciting a plasma wake wave. We present an analytical description of the strongly nonlinear oscillations showing that the magnetic field prevents closing of the cavity formed behind the laser pulse. This effect is demonstrated with 3D PIC simulations of the laser-plasma interaction. An analysis of the betatron oscillations of fast electrons in the presence of the magnetic field reveals a characteristic Four-Ray Star pattern.

  9. Determination of the Neutron Magnetic Moment

    DOE R&D Accomplishments [OSTI]

    Greene, G. L.; Ramsey, N. F.; Mampe, W.; Pendlebury, J. M.; Smith, K.; Dress, W. B.; Miller, P. D.; Perrin, P.

    1981-06-01

    The neutron magnetic moment has been measured with an improvement of a factor of 100 over the previous best measurement. Using a magnetic resonance spectrometer of the separated oscillatory field type capable of determining a resonance signal for both neutrons and protons (in flowing H{sub 2}O), we find ..mu..{sub n}/..mu..{sub p} = 0.68497935(17) (0.25 ppM). The neutron magnetic moment can also be expressed without loss of accuracy in a variety of other units.

  10. Cooling system for superconducting magnet

    DOE Patents [OSTI]

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

    1998-12-15

    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.

  11. Cooling system for superconducting magnet

    DOE Patents [OSTI]

    Gamble, Bruce B. (Wellesley, MA); Sidi-Yekhlef, Ahmed (Framingham, MA)

    1998-01-01

    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.

  12. 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)

    2008-07-22

    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.

  13. THE SUBMILLIMETER AND MILLIMETER EXCESS OF THE SMALL MAGELLANIC CLOUD: MAGNETIC DIPOLE EMISSION FROM MAGNETIC NANOPARTICLES?

    SciTech Connect (OSTI)

    Draine, B. T.; Hensley, Brandon

    2012-09-20

    The Small Magellanic Cloud (SMC) has surprisingly strong submillimeter- and millimeter-wavelength emission that is inconsistent with standard dust models, including those with emission from spinning dust. Here, we show that the emission from the SMC may be understood if the interstellar dust mixture includes magnetic nanoparticles, emitting magnetic dipole radiation resulting from thermal fluctuations in the magnetization. The magnetic grains can be metallic iron, magnetite Fe{sub 3}O{sub 4}, or maghemite {gamma}-Fe{sub 2}O{sub 3}. The required mass of iron is consistent with elemental abundance constraints. The magnetic dipole emission is predicted to be polarized orthogonally to the normal electric dipole radiation if the nanoparticles are inclusions in larger grains. We speculate that other low-metallicity galaxies may also have a large fraction of the interstellar Fe in magnetic materials.

  14. 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)

    2010-02-09

    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.

  15. Disorder-Induced Microscopic Magnetic Memory

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

    Magnets are not just for refrigerator doors-they are of paramount importance in today's digital information age. In the face of a rapidly growing appetite for data storage,...

  16. Final Technical Progress Report NANOSTRUCTURED MAGNETIC MATERIALS

    SciTech Connect (OSTI)

    Charles M. Falco

    2012-09-13

    This report describes progress made during the final phase of our DOE-funded program on Nanostructured Magnetic Materials. This period was quite productive, resulting in the submission of three papers and presentation of three talks at international conferences and three seminars at research institutions. Our DOE-funded research efforts were directed toward studies of magnetism at surfaces and interfaces in high-quality, well-characterized materials prepared by Molecular Beam Epitaxy (MBE) and sputtering. We have an exceptionally well-equipped laboratory for these studies, with: Thin film preparation equipment; Characterization equipment; Equipment to study magnetic properties of surfaces and ultra-thin magnetic films and interfaces in multi-layers and superlattices.

  17. Electronic structure, magnetic properties, and magnetostructural...

    Office of Scientific and Technical Information (OSTI)

    Electronic structure, magnetic properties, and magnetostructural transition in Tb5Si2.2Ge1.8 from first principles Citation Details In-Document Search Title: Electronic structure, ...

  18. Hidden Rotational Symmetries in Magnetic Domain Patterns

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

    low-temperature control, and high coherent x-ray flux. The sample used was a CoPd multilayer film that shows perpendicular anisotropy, meaning the magnetization points...

  19. Magnetic island evolution in hot ion plasmas

    SciTech Connect (OSTI)

    Ishizawa, A.; Nakajima, N.; Waelbroeck, F. L.; Fitzpatrick, R.; Horton, W.

    2012-07-15

    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.

  20. "Plasma Thruster with Magnetically Insulated Anode: Inventor...

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

    at least two stages, ionization and acceleration, which are physically separated by the geometry, magnetic field topology and in the case of DC - FR power, by the localized RF...

  1. Direct Imaging of Asymmetric Magnetization Reversal

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

    and H. Ohldag, "Direct imaging of asymmetric magnetization reversal in exchange-biased FeMnPd bilayers by x-ray photoemission electron microscopy," Phys. Rev. Lett. 94, 107203...

  2. Direct Imaging of Asymmetric Magnetization Reversal

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

    H. Ohldag, "Direct imaging of asymmetric magnetization reversal in exchange-biased FeMnPd bilayers by x-ray photoemission electron microscopy," Phys. Rev. Lett. 94, 107203 (2005...

  3. CMC Magnetics Corporation | Open Energy Information

    Open Energy Info (EERE)

    Taiwan Sector: Solar Product: A Taiwanese compact disk manufacturer who has set up a solar cell unit. References: CMC Magnetics Corporation1 This article is a stub. You can...

  4. Hidden Rotational Symmetries in Magnetic Domain Patterns

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

    patterns that may or may not repeat with each cycle through a hysteresis loop. A magnetic thin film with perpendicular anisotropy, such as that used in computer hard drives, for...

  5. Perpendicular Magnetism Unparalleled Find in Single Crystal ...

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

    order coexisting in a single sample. Article Title: Itinerant Ferromagnetism in the As 4p Conduction Band of Ba0.6K0.4Mn2As2 Identified by X-Ray Magnetic Circular Dichroism...

  6. 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

    2011-02-22

    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.

  7. Quadrupole magnet for a rapid cycling synchrotron

    SciTech Connect (OSTI)

    Witte, H.; Berg, J. S.

    2015-05-03

    Rapid Cycling Synchrotrons (RCS) feature interleaved warm and cold dipole magnets; the field of the warm magnets is used to modulate the average bending field depending on the particle energy. It has been shown that RCS can be an attractive option for fast acceleration of particles, for example, muons, which decay quickly. In previous studies it was demonstrated that in principle warm dipole magnets can be designed which can provide the required ramp rates, which are equivalent to frequencies of about 1 kHz. To reduce the losses it is beneficial to employ two separate materials for the yoke; it was also shown that by employing an optimized excitation coil geometry the eddy current losses are acceptable. In this paper we show that the same principles can be applied to quadrupole magnets targeting 30 T/m with a repetition rate of 1kHz and good field quality.

  8. Magnetic Reconnection Experiment (MRX) | Princeton Plasma Physics...

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

    was built to study a fundamental plasma process in a controlled laboratory environment. A plasma is a hot, ionized gas that can be confined using a magnetic field. Plasmas are...

  9. Helicopter magnetic survey conducted to locate wells

    SciTech Connect (OSTI)

    Veloski, G.A.; Hammack, R.W.; Stamp, V.; Hall, R.; Colina, K.

    2008-07-01

    A helicopter magnetic survey was conducted in August 2007 over 15.6 sq mi at the Naval Petroleum Reserve No. 3s (NPR-3) Teapot Dome Field near Casper, Wyoming. The surveys 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.

  10. DOES MAGNETIC-FIELD-ROTATION MISALIGNMENT SOLVE THE MAGNETIC BRAKING CATASTROPHE IN PROTOSTELLAR DISK FORMATION?

    SciTech Connect (OSTI)

    Li Zhiyun [Astronomy Department, University of Virginia, Charlottesville, VA (United States); Krasnopolsky, Ruben; Shang, Hsien [Academia Sinica, Theoretical Institute for Advanced Research in Astrophysics, Taipei, Taiwan (China)

    2013-09-01

    Stars form in dense cores of molecular clouds that are observed to be significantly magnetized. In the simplest case of a laminar (non-turbulent) core with the magnetic field aligned with the rotation axis, both analytic considerations and numerical simulations have shown that the formation of a large, 10{sup 2} AU scale, rotationally supported protostellar disk is suppressed by magnetic braking in the ideal MHD limit for a realistic level of core magnetization. This theoretical difficulty in forming protostellar disks is termed the ''magnetic braking catastrophe''. A possible resolution to this problem, proposed by Hennebelle and Ciardi and Joos et al., is that misalignment between the magnetic field and rotation axis may weaken the magnetic braking enough to enable disk formation. We evaluate this possibility quantitatively through numerical simulations. We confirm the basic result of Joos et al. that the misalignment is indeed conducive to disk formation. In relatively weakly magnetized cores with dimensionless mass-to-flux ratio {approx}> 4, it enabled the formation of rotationally supported disks that would otherwise be suppressed if the magnetic field and rotation axis are aligned. For more strongly magnetized cores, disk formation remains suppressed, however, even for the maximum tilt angle of 90 Degree-Sign . If dense cores are as strongly magnetized as indicated by OH Zeeman observations (with a mean dimensionless mass-to-flux ratio {approx}2), it would be difficult for the misalignment alone to enable disk formation in the majority of them. We conclude that, while beneficial to disk formation, especially for the relatively weak field case, misalignment does not completely solve the problem of catastrophic magnetic braking in general.

  11. Laminated grid and web magnetic cores

    DOE Patents [OSTI]

    Sefko, John; Pavlik, Norman M.

    1984-01-01

    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.

  12. Design of a Geothermal Downhole Magnetic Flowmeter

    SciTech Connect (OSTI)

    Glowka, Dave A.; Normann, Randy A.

    2015-06-15

    This paper covers the development of a 300°C geothermal solid-state magnetic flowmeter (or magmeter) to support in situ monitoring of future EGS (enhanced geothermal system) production wells. Existing flowmeters are simple mechanical spinner sensors. These mechanical sensors fail within as little as 10 hrs, while a solid-state magmeter has the potential for months/years of operation. The design and testing of a magnetic flow sensor for use with existing high-temperature electronics is presented.

  13. Pinpointing the Magnetic Moments of Nuclear Matter

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

    Pinpointing the Magnetic Moments of Nuclear Matter Pinpointing the Magnetic Moments of Nuclear Matter Lattice QCD Calculations Reveal Inner Workings of Lightest Nuclei January 20, 2015 Contact: Kathy Kincade, +1 510 495 2124, kkincade@lbl.gov h3lattice Artist's impression of a triton, the atomic nucleus of a tritium atom. The image shows blue neutrons and a red proton with quarks inside; the arrows indicate the alignments of the spins. Image: William Detmold, MIT A team of nuclear physicists has

  14. Ancient galactic magnetic fields stronger than expected

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

    Ancient galactic magnetic fields Ancient galactic magnetic fields stronger than expected With powerful telescopes and sophisticated measurements, the team probed back in time to see the ancient universe as it existed some 8 to 9 billion years ago. July 23, 2008 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma

  15. Magnetics + Mechanics + Nanoscale = Electromagnetics Future (Tuesday, March

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

    15) | The Ames Laboratory Magnetics + Mechanics + Nanoscale = Electromagnetics Future (Tuesday, March 15) DATE: Tuesday, March 15, 1:10 pm LOCATION: 3043 Coover Hall Greg P. Carman, Professor, Mechanical and Aerospace Engineering Department, UCLA Henry Samueli School of Engineering and Applied Science, University of California, Los Angeles. Efficient control of small scale magnetism presents a significant problem for future miniature electromagnetic devices. In most macroscale

  16. MULTISCALE DYNAMICS OF SOLAR MAGNETIC STRUCTURES

    SciTech Connect (OSTI)

    Uritsky, Vadim M.; Davila, Joseph M.

    2012-03-20

    Multiscale topological complexity of the 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 these 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.) 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 the 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.

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

    SciTech Connect (OSTI)

    2012-01-01

    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 todays 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.

  18. Structures and magnetic properties of Co-Zr-B magnets studied...

    Office of Scientific and Technical Information (OSTI)

    polymorphs, and such motif plays a key role in achieving strong magnetic anisotropy. Boron atoms were found to be able to substitute cobalt atoms or occupy the "interruption"...

  19. Magnetic anisotropy in Ta/CoFeB/MgO investigated by x-ray magnetic...

    Office of Scientific and Technical Information (OSTI)

    AND SUPERFLUIDITY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANISOTROPY; BORON ALLOYS; COBALT; COBALT ALLOYS; IRON; IRON ALLOYS; MAGNESIUM OXIDES; MAGNETIC CIRCULAR...

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

    SciTech Connect (OSTI)

    2012-01-01

    REACT Project: Dartmouth is developing specialized alloys with magnetic properties superior to the rare earths used in todays 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.

  1. Repetitive formation and decay of current sheets in magnetic loops: An origin of diverse magnetic structures

    SciTech Connect (OSTI)

    Kumar, Dinesh; Bhattacharyya, R.; Smolarkiewicz, P. K.

    2015-01-15

    In this work, evolution of an incompressible, thermally homogeneous, infinitely conducting, viscous magnetofluid is numerically explored as the fluid undergoes repeated events of magnetic reconnection. The initial magnetic field is constructed by a superposition of two linear force-free fields and has similar morphology as the magnetic loops observed in the solar corona. The results are presented for computations with three distinct sets of footpoint geometries. To onset reconnection, we rely on numerical model magnetic diffusivity, in the spirit of implicit large eddy simulation. It is generally expected that in a high Lundquist number fluid, repeated magnetic reconnections are ubiquitous and hence can lead to a host of magnetic structures with considerable observational importance. In particular, the simulations presented here illustrate formations of magnetic islands, rotating magnetic helices and rising flux ropes—depending on the initial footpoint geometry but through the common process of repeated magnetic reconnections. Further, we observe the development of extended current sheets in two case studies, where the footpoint reconnections generate favorable dynamics.

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

    SciTech Connect (OSTI)

    Crooker, Scott A; Samarth, Nitin

    2008-01-01

    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.

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

    SciTech Connect (OSTI)

    Lynn, Alan G. Gilmore, Mark

    2014-11-15

    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.

  4. Magnetic order in the induced magnetic moment system Pr3In

    SciTech Connect (OSTI)

    Fanelli, V. R.; Christianson, Andrew D; Jaime, M.; Thompson, J. D.; Lawrence, J. M.; Suzuki, H. S.

    2008-01-01

    Pr3In is a single ground state compound which exhibits antiferromagnetic order below 11.4 K due to the exchange induced admixture of crystalline electric field levels. Additional information regarding the complex magnetic behavior of this compound can be gained through application of magnetic fields. We report specific heat and magnetocaloric effect measurements to 15 T and magnetization measurements to 44 T on single crystal samples of Pr3In. A new magnetic phase is revealed above 1.9 T and below 11.4 K.

  5. Magnetic field transfer device and method

    DOE Patents [OSTI]

    Wipf, S.L.

    1990-02-13

    A magnetic field transfer device includes a pair of oppositely wound inner coils which each include at least one winding around an inner coil axis, and an outer coil which includes at least one winding around an outer coil axis. The windings may be formed of superconductors. The axes of the two inner coils are parallel and laterally spaced from each other so that the inner coils are positioned in side-by-side relation. The outer coil is outwardly positioned from the inner coils and rotatable relative to the inner coils about a rotational axis substantially perpendicular to the inner coil axes to generate a hypothetical surface which substantially encloses the inner coils. The outer coil rotates relative to the inner coils between a first position in which the outer coil axis is substantially parallel to the inner coil axes and the outer coil augments the magnetic field formed in one of the inner coils, and a second position 180[degree] from the first position, in which the augmented magnetic field is transferred into the other inner coil and reoriented 180[degree] from the original magnetic field. The magnetic field transfer device allows a magnetic field to be transferred between volumes with negligible work being required to rotate the outer coil with respect to the inner coils. 16 figs.

  6. Magnetic field transfer device and method

    DOE Patents [OSTI]

    Wipf, Stefan L. (Hamburg, DE)

    1990-01-01

    A magnetic field transfer device includes a pair of oppositely wound inner coils which each include at least one winding around an inner coil axis, and an outer coil which includes at least one winding around an outer coil axis. The windings may be formed of superconductors. The axes of the two inner coils are parallel and laterally spaced from each other so that the inner coils are positioned in side-by-side relation. The outer coil is outwardly positioned from the inner coils and rotatable relative to the inner coils about a rotational axis substantially perpendicular to the inner coil axes to generate a hypothetical surface which substantially encloses the inner coils. The outer coil rotates relative to the inner coils between a first position in which the outer coil axis is substantially parallel to the inner coil axes and the outer coil augments the magnetic field formed in one of the inner coils, and a second position 180.degree. from the first position, in which the augmented magnetic field is transferred into the other inner coil and reoriented 180.degree. from the original magnetic field. The magnetic field transfer device allows a magnetic field to be transferred between volumes with negligible work being required to rotate the outer coil with respect to the inner coils.

  7. Fundamental Scientific Problems in Magnetic Recording

    SciTech Connect (OSTI)

    Schulthess, T.C.; Miller, M.K.

    2007-06-27

    Magnetic data storage technology is presently leading the high tech industry in advancing device integration--doubling the storage density every 12 months. To continue these advancements and to achieve terra bit per inch squared recording densities, new approaches to store and access data will be needed in about 3-5 years. In this project, collaboration between Oak Ridge National Laboratory (ORNL), Center for Materials for Information Technology (MINT) at University of Alabama (UA), Imago Scientific Instruments, and Seagate Technologies, was undertaken to address the fundamental scientific problems confronted by the industry in meeting the upcoming challenges. The areas that were the focus of this study were to: (1) develop atom probe tomography for atomic scale imaging of magnetic heterostructures used in magnetic data storage technology; (2) develop a first principles based tools for the study of exchange bias aimed at finding new anti-ferromagnetic materials to reduce the thickness of the pinning layer in the read head; (3) develop high moment magnetic materials and tools to study magnetic switching in nanostructures aimed at developing improved writers of high anisotropy magnetic storage media.

  8. MAGNETIC LOOPS IN THE QUIET SUN

    SciTech Connect (OSTI)

    Wiegelmann, T.; Solanki, S. K.; Barthol, P.; Gandorfer, A.; Borrero, J. M.; Schmidt, W.; Pillet, V. MartInez; Bonet, J. A.; Domingo, V.; Knoelker, M.; Title, A. M.

    2010-11-10

    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.

  9. Dynamically stable magnetic suspension/bearing system

    DOE Patents [OSTI]

    Post, R.F.

    1996-02-27

    A magnetic bearing system contains magnetic subsystems which act together to support a rotating element in a state of dynamic equilibrium. However, owing to the limitations imposed by Earnshaw`s Theorem, the magnetic bearing systems to be described do not possess a stable equilibrium at zero rotational speed. Therefore, mechanical stabilizers are provided, in each case, to hold the suspended system in equilibrium until its speed has exceeded a low critical speed where dynamic effects take over, permitting the achievement of a stable equilibrium for the rotating object. A state of stable equilibrium is achieved above a critical speed by use of a collection of passive elements using permanent magnets to provide their magnetomotive excitation. The magnetic forces exerted by these elements, when taken together, levitate the rotating object in equilibrium against external forces, such as the force of gravity or forces arising from accelerations. At the same time, this equilibrium is made stable against displacements of the rotating object from its equilibrium position by using combinations of elements that possess force derivatives of such magnitudes and signs that they can satisfy the conditions required for a rotating body to be stably supported by a magnetic bearing system over a finite range of those displacements. 32 figs.

  10. Dynamically stable magnetic suspension/bearing system

    DOE Patents [OSTI]

    Post, Richard F. (Walnut Creek, CA)

    1996-01-01

    A magnetic bearing system contains magnetic subsystems which act together to support a rotating element in a state of dynamic equilibrium. However, owing to the limitations imposed by Earnshaw's Theorem, the magnetic bearing systems to be described do not possess a stable equilibrium at zero rotational speed. Therefore, mechanical stabilizers are provided, in each case, to hold the suspended system in equilibrium until its speed has exceeded a low critical speed where dynamic effects take over, permitting the achievement of a stable equilibrium for the rotating object. A state of stable equilibrium is achieved above a critical speed by use of a collection of passive elements using permanent magnets to provide their magnetomotive excitation. The magnetic forces exerted by these elements, when taken together, levitate the rotating object in equilibrium against external forces, such as the force of gravity or forces arising from accelerations. At the same time, this equilibrium is made stable against displacements of the rotating object from its equilibrium position by using combinations of elements that possess force derivatives of such magnitudes and signs that they can satisfy the conditions required for a rotating body to be stably supported by a magnetic bearing system over a finite range of those displacements.

  11. Permanent magnet design for high-speed superconducting bearings

    DOE Patents [OSTI]

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

    1996-09-10

    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.

  12. Permanent magnet design for high-speed superconducting bearings

    DOE Patents [OSTI]

    Hull, John R.; Uherka, Kenneth L.; Abdoud, Robert G.

    1996-01-01

    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.

  13. High magnetic field ohmically decoupled non-contact technology

    DOE Patents [OSTI]

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

    2009-05-19

    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.

  14. Propulsion and stabilization system for magnetically levitated vehicles

    DOE Patents [OSTI]

    Coffey, Howard T. (Darien, IL)

    1993-06-29

    A propulsion and stabilization system for an inductive repulsion type magnetically levitated vehicle which is propelled and stabilized by a system which includes propulsion windings mounted above and parallel to vehicle-borne suspension magnets. A linear synchronous motor is part of the vehicle guideway and is mounted above and parallel to superconducting magnets attached to the magnetically levitated vehicle.

  15. High performance hybrid magnetic structure for biotechnology applications

    DOE Patents [OSTI]

    Humphries, David E.; Pollard, Martin J.; Elkin, Christopher J.

    2006-12-12

    The present disclosure provides a high performance hybrid magnetic structure made from a combination of permanent magnets and ferromagnetic pole materials which are assembled in a predetermined array. The hybrid magnetic structure provides for separation and other biotechnology applications involving holding, manipulation, or separation of magnetic or magnetizable molecular structures and targets. Also disclosed are: a method of assembling the hybrid magnetic plates, a high throughput protocol featuring the hybrid magnetic structure, and other embodiments of the ferromagnetic pole shape, attachment and adapter interfaces for adapting the use of the hybrid magnetic structure for use with liquid handling and other robots for use in high throughput processes.

  16. Mitigated-force carriage for high magnetic field environments

    DOE Patents [OSTI]

    Ludtka, Gerard M.; Ludtka, Gail M.; Wilgen, John B.; Murphy, Bart L.

    2015-05-19

    A carriage for high magnetic field environments includes a plurality of work-piece separators disposed in an operable relationship with a work-piece processing magnet having a magnetic field strength of at least 1 Tesla for supporting and separating a plurality of work-pieces by a preselected, essentially equal spacing, so that, as a first work-piece is inserted into the magnetic field, a second work-piece is simultaneously withdrawn from the magnetic field, so that an attractive magnetic force imparted on the first work-piece offsets a resistive magnetic force imparted on the second work-piece.

  17. Toroidal constant-tension superconducting magnetic energy storage units

    DOE Patents [OSTI]

    Herring, J.S.

    1992-11-03

    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.

  18. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Magnetic Vortex Core Reversal by Low-Field Excitations Print Wednesday, 28 March 2007 00:00 In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to

  19. Proximity-induced magnetism in transition-metal substituted graphene

    SciTech Connect (OSTI)

    Crook, Charles B.; Constantin, Costel; Ahmed, Towfiq; Zhu, Jian -Xin; Balatsky, Alexander V.; Haraldsen, Jason T.

    2015-08-03

    We investigate the interactions between two identical magnetic impurities substituted into a graphene superlattice. Using a first-principles approach, we calculate the electronic and magnetic properties for transition-metal substituted graphene systems with varying spatial separation. These calculations are compared for three different magnetic impurities, manganese, chromium, and vanadium. We determine the electronic band structure, density of states, and Millikan populations (magnetic moment) for each atom, as well as calculate the exchange parameter between the two magnetic atoms as a function of spatial separation. We find that the presence of magnetic impurities establishes a distinct magnetic moment in the graphene lattice, where the interactions are highly dependent on the spatial and magnetic characteristic between the magnetic and carbon atoms, which leads to either ferromagnetic or antiferromagnetic behavior. Furthermore, through an analysis of the calculated exchange energies and partial density of states, it is determined that interactions between the magnetic atoms can be classified as an RKKY interaction.

  20. Adjustable permanent magnet assembly for NMR and MRI

    DOE Patents [OSTI]

    Pines, Alexander; Paulsen, Jeffrey; Bouchard, Louis S; Blumich, Bernhard

    2013-10-29

    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.

  1. Magnetic and Superconducting Materials at High Pressures

    SciTech Connect (OSTI)

    Struzhkin, Viktor V.

    2015-03-24

    The work concentrates on few important tasks in enabling techniques for search of superconducting compressed hydrogen compounds and pure hydrogen, investigation of mechanisms of high-Tc superconductivity, and exploring new superconducting materials. Along that route we performed several challenging tasks, including discovery of new forms of polyhydrides of alkali metal Na at very high pressures. These experiments help us to establish the experimental environment that will provide important information on the high-pressure properties of hydrogen-rich compounds. Our recent progress in RIXS measurements opens a whole field of strongly correlated 3d materials. We have developed a systematic approach to measure major electronic parameters, like Hubbard energy U, and charge transfer energy Δ, as function of pressure. This technique will enable also RIXS studies of magnetic excitations in iridates and other 5d materials at the L edge, which attract a lot of interest recently. We have developed new magnetic sensing technique based on optically detected magnetic resonance from NV centers in diamond. The technique can be applied to study superconductivity in high-TC materials, to search for magnetic transitions in strongly correlated and itinerant magnetic materials under pressure. Summary of Project Activities; development of high-pressure experimentation platform for exploration of new potential superconductors, metal polyhydrides (including newly discovered alkali metal polyhydrides), and already known superconductors at the limit of static high-pressure techniques; investigation of special classes of superconducting compounds (high-Tc superconductors, new superconducting materials), that may provide new fundamental knowledge and may prove important for application as high-temperature/high-critical parameter superconductors; investigation of the pressure dependence of superconductivity and magnetic/phase transformations in 3d transition metal compounds, including transitions from magnetic to nonmagnetic phases in a broad pressure-temperature range; using X-ray methods including the newly developed RIXS high-pressure technique to explore pressure-tuned electronic excitations in strongly correlated 3d-materials; and advancing transport and magnetic techniques for measurements on small samples at very high pressures in a wide temperature range, with the application of focused ion beam technology and photolithography tailored to the design of microcircuits down to a nanoscale size, thus expanding the horizon in the search for novel physical phenomena at ultrahigh pressures. Apply new optical magnetic sensing techniques with NV- centers in diamond to detect superconductivity and magnetic transitions with unprecedented spatial resolution.

  2. Stochastic Domain-Wall Depinning in Magnetic Nanowires

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

    Stochastic Domain-Wall Depinning in Magnetic Nanowires Stochastic Domain-Wall Depinning in Magnetic Nanowires Print Wednesday, 29 July 2009 00:00 Reliably controlling the motion of magnetic domain walls along magnetic nanowires is a key requirement for current technological development of novel classes of logic and storage devices, but understanding the nature of non-deterministic domain-wall motion remains a scientific challenge. A statistical analysis of high-resolution magnetic soft x-ray

  3. Structural modulations and magnetic properties of off-stoichiometric

    Office of Scientific and Technical Information (OSTI)

    Ni-Mn-Ga magnetic shape memory alloys (Journal Article) | DOE PAGES Structural modulations and magnetic properties of off-stoichiometric Ni-Mn-Ga magnetic shape memory alloys Title: Structural modulations and magnetic properties of off-stoichiometric Ni-Mn-Ga magnetic shape memory alloys Authors: Pramanick, A. ; Wang, X. P. ; An, K. ; Stoica, A. D. ; Yi, J. ; Gai, Z. ; Hoffmann, C. ; Wang, X.-L. Publication Date: 2012-04-16 OSTI Identifier: 1098736 Type: Publisher's Accepted Manuscript

  4. Circular polarization of obliquely propagating whistler wave magnetic field

    SciTech Connect (OSTI)

    Bellan, P. M.

    2013-08-15

    The circular polarization of the magnetic field of obliquely propagating whistler waves is derived using a basis set associated with the wave partial differential equation. The wave energy is mainly magnetic and the wave propagation consists of this magnetic energy sloshing back and forth between two orthogonal components of magnetic field in quadrature. The wave electric field energy is small compared to the magnetic field energy.

  5. Magnetic spectroscopy and microscopy of functional materials

    SciTech Connect (OSTI)

    Jenkins, C.A.

    2011-01-28

    Heusler intermetallics Mn{sub 2}Y Ga and X{sub 2}MnGa (X; Y =Fe, Co, Ni) undergo tetragonal magnetostructural transitions that can result in half metallicity, magnetic shape memory, or the magnetocaloric effect. Understanding the magnetism and magnetic behavior in functional materials is often the most direct route to being able to optimize current materials for todays applications and to design novel ones for tomorrow. Synchrotron soft x-ray magnetic spectromicroscopy techniques are well suited to explore the the competing effects from the magnetization and the lattice parameters in these materials as they provide detailed element-, valence-, and site-specifc information on the coupling of crystallographic ordering and electronic structure as well as external parameters like temperature and pressure on the bonding and exchange. Fundamental work preparing the model systems of spintronic, multiferroic, and energy-related compositions is presented for context. The methodology of synchrotron spectroscopy is presented and applied to not only magnetic characterization but also of developing a systematic screening method for future examples of materials exhibiting any of the above effects. The chapter progression is as follows: an introduction to the concepts and materials under consideration (Chapter 1); an overview of sample preparation techniques and results, and the kinds of characterization methods employed (Chapter 2); spectro- and microscopic explorations of X{sub 2}MnGa/Ge (Chapter 3); spectroscopic investigations of the composition series Mn{sub 2}Y Ga to the logical Mn{sub 3}Ga endpoint (Chapter 4); and a summary and overview of upcoming work (Chapter 5). Appendices include the results of a Think Tank for the Graduate School of Excellence MAINZ (Appendix A) and details of an imaging project now in progress on magnetic reversal and domain wall observation in the classical Heusler material Co{sub 2}FeSi (Appendix B).

  6. NMR system and method having a permanent magnet providing a rotating magnetic field

    SciTech Connect (OSTI)

    Schlueter, Ross D; Budinger, Thomas F

    2009-05-19

    Disclosed herein are systems and methods for generating a rotating magnetic field. The rotating magnetic field can be used to obtain rotating-field NMR spectra, such as magic angle spinning spectra, without having to physically rotate the sample. This result allows magic angle spinning NMR to be conducted on biological samples such as live animals, including humans.

  7. Magnetic and Cryogenic Design of the MICE Coupling Solenoid Magnet System

    SciTech Connect (OSTI)

    Wang, Li; Xu, FengYu; Wu, Hong; Liu, XiaoKum; Li, LanKai; Guo, XingLong; Chen, AnBin; Green, Michael A; Li, D.R.; Virostek, Steve; Pan, H.

    2008-08-02

    The Muon Ionization Cooling Experiment (MICE) will demonstrate ionization cooling in a short section of a realistic cooling channel using a muon beam at Rutherford Appleton Laboratory in the UK. The coupling magnet is a superconducting solenoid mounted around four 201MHz RF cavities, which produces magnetic field up to 2.6 T on the magnet centerline to keep muons within the iris of RF cavities windows. The coupling coil with inner radius of 750mm, length of 285mm and thickness of 102.5mm will be cooled by a pair of 1.5 W at 4.2 K small coolers. This paper will introduce the updated engineering design of the coupling magnet made by ICST in China. The detailed analyses on magnetic fields, stresses induced during the processes of winding, cool down and charging, and cold mass support assembly are presented as well.

  8. Proximity-driven enhanced magnetic order at ferromagnetic-insulator-magnetic-topological-insulator interface

    SciTech Connect (OSTI)

    Li, Mingda; Zhu, Yimei; Chang, Cui -Zu; Kirby, B. J.; Jamer, Michelle E.; Cui, Wenping; Wu, Lijun; Wei, Peng; Heiman, Don; Li, Ju; Moodera, Jagadeesh S.; Katmis, Ferhat

    2015-08-17

    Magnetic exchange driven proximity effect at a magnetic-insulator–topological-insulator (MI-TI) interface provides a rich playground for novel phenomena as well as a way to realize low energy dissipation quantum devices. In this study, we report a dramatic enhancement of proximity exchange coupling in the MI/magnetic-TI EuS/Sb2–xVxTe3 hybrid heterostructure, where V doping is used to drive the TI (Sb2Te3) magnetic. We observe an artificial antiferromagneticlike structure near the MI-TI interface, which may account for the enhanced proximity coupling. The interplay between the proximity effect and doping in a hybrid heterostructure provides insights into the engineering of magnetic ordering.

  9. Simulation of magnetic hysteresis loops and magnetic Barkhausen noise of α-iron containing nonmagnetic particles

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

    Li, Yi; Xu, Ben; Hu, Shenyang; Li, Yulan; Li, Qiulin; Liu, Wei

    2015-07-01

    The magnetic hysteresis loops and Barkhausen noise of a single α-iron with nonmagnetic particles are simulated to investigate into the magnetic hardening due to Cu-rich precipitates in irradiated reactor pressure vessel (RPV) steels. Phase field method basing Landau-Lifshitz-Gilbert (LLG) equation is used for this simulation. The results show that the presence of the nonmagnetic particle could result in magnetic hardening by making the nucleation of reversed domains difficult. The coercive field is found to increase, while the intensity of Barkhausen noise voltage is decreased when the nonmagnetic particle is introduced. Simulations demonstrate the impact of nucleation field of reversed domainsmore » on the magnetization reversal behavior and the magnetic properties.« less

  10. Proximity-driven enhanced magnetic order at ferromagnetic-insulator-magnetic-topological-insulator interface

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

    Li, Mingda; Zhu, Yimei; Chang, Cui -Zu; Kirby, B. J.; Jamer, Michelle E.; Cui, Wenping; Wu, Lijun; Wei, Peng; Heiman, Don; Li, Ju; et al

    2015-08-17

    Magnetic exchange driven proximity effect at a magnetic-insulator–topological-insulator (MI-TI) interface provides a rich playground for novel phenomena as well as a way to realize low energy dissipation quantum devices. In this study, we report a dramatic enhancement of proximity exchange coupling in the MI/magnetic-TI EuS/Sb2–xVxTe3 hybrid heterostructure, where V doping is used to drive the TI (Sb2Te3) magnetic. We observe an artificial antiferromagneticlike structure near the MI-TI interface, which may account for the enhanced proximity coupling. The interplay between the proximity effect and doping in a hybrid heterostructure provides insights into the engineering of magnetic ordering.

  11. Atomic magnetic gradiometer for room temperature high sensitivity magnetic field detection

    DOE Patents [OSTI]

    Xu,Shoujun (Berkeley, CA); Lowery, Thomas L. (Belmont, MA); Budker, Dmitry (El Cerrito, CA); Yashchuk, Valeriy V. (Richmond, CA); Wemmer, David E. (Berkeley, CA); Pines, Alexander (Berkeley, CA)

    2009-08-11

    A laser-based atomic magnetometer (LBAM) apparatus measures magnetic fields, comprising: a plurality of polarization detector cells to detect magnetic fields; a laser source optically coupled to the polarization detector cells; and a signal detector that measures the laser source after being coupled to the polarization detector cells, which may be alkali cells. A single polarization cell may be used for nuclear magnetic resonance (NMR) by prepolarizing the nuclear spins of an analyte, encoding spectroscopic and/or spatial information, and detecting NMR signals from the analyte with a laser-based atomic magnetometer to form NMR spectra and/or magnetic resonance images (MRI). There is no need of a magnetic field or cryogenics in the detection step, as it is detected through the LBAM.

  12. Method for the detection of a magnetic field utilizing a magnetic vortex

    DOE Patents [OSTI]

    Novosad, Valentyn (Chicago, IL); Buchanan, Kristen (Batavia, IL)

    2010-04-13

    The determination of the strength of an in-plane magnetic field utilizing one or more magnetically-soft, ferromagnetic member, having a shape, size and material whereas a single magnetic vortex is formed at remanence in each ferromagnetic member. The preferred shape is a thin circle, or dot. Multiple ferromagnetic members can also be stacked on-top of each other and separated by a non-magnetic spacer. The resulting sensor is hysteresis free. The sensor's sensitivity, and magnetic saturation characteristics may be easily tuned by simply altering the material, size, shape, or a combination thereof to match the desired sensitivity and saturation characteristics. The sensor is self-resetting at remanence and therefore does not require any pinning techniques.

  13. Scaling laws in magnetized plasma turbulence

    SciTech Connect (OSTI)

    Boldyrev, Stanislav

    2015-06-28

    Interactions of plasma motion with magnetic fields occur in nature and in the laboratory in an impressively broad range of scales, from megaparsecs in astrophysical systems to centimeters in fusion devices. The fact that such an enormous array of phenomena can be effectively studied lies in the existence of fundamental scaling laws in plasma turbulence, which allow one to scale the results of analytic and numerical modeling to the sized of galaxies, velocities of supernovae explosions, or magnetic fields in fusion devices. Magnetohydrodynamics (MHD) provides the simplest framework for describing magnetic plasma turbulence. Recently, a number of new features of MHD turbulence have been discovered and an impressive array of thought-provoking phenomenological theories have been put forward. However, these theories have conflicting predictions, and the currently available numerical simulations are not able to resolve the contradictions. MHD turbulence exhibits a variety of regimes unusual in regular hydrodynamic turbulence. Depending on the strength of the guide magnetic field it can be dominated by weakly interacting Alfv\\'en waves or strongly interacting wave packets. At small scales such turbulence is locally anisotropic and imbalanced (cross-helical). In a stark contrast with hydrodynamic turbulence, which tends to ``forget'' global constrains and become uniform and isotropic at small scales, MHD turbulence becomes progressively more anisotropic and unbalanced at small scales. Magnetic field plays a fundamental role in turbulent dynamics. Even when such a field is not imposed by external sources, it is self-consistently generated by the magnetic dynamo action. This project aims at a comprehensive study of universal regimes of magnetic plasma turbulence, combining the modern analytic approaches with the state of the art numerical simulations. The proposed study focuses on the three topics: weak MHD turbulence, which is relevant for laboratory devices, the solar wind, solar corona heating, and planetary magnetospheres; strong MHD turbulence, which is relevant for fusion devices, star formation, cosmic rays acceleration, scattering and trapping in galaxies, as well as many aspects of dynamics, distribution and composition of space plasmas, and the process of magnetic dynamo action, which explains the generation and the structure of magnetic fields in turbulent plasmas. The planned work will aim at developing new analytic approaches, conducting new numerical simulations with currently unmatched resolution, and training students in the methods of the modern theory of plasma turbulence. The work will be performed at the University of Wisconsin--Madison.

  14. Magnetization dynamics of cobalt grown on graphene

    SciTech Connect (OSTI)

    Berger, A. J.; White, S. P.; Adur, R.; Pu, Y.; Hammel, P. C.; Amamou, W.; Kawakami, R. K.

    2014-05-07

    Ferromagnetic resonance (FMR) spin pumping is a rapidly growing field which has demonstrated promising results in a variety of material systems. This technique utilizes the resonant precession of magnetization in a ferromagnet to inject spin into an adjacent non-magnetic material. Spin pumping into graphene is attractive on account of its exceptional spin transport properties. This article reports on FMR characterization of cobalt grown on chemical vapor deposition graphene and examines the validity of linewidth broadening as an indicator of spin pumping. In comparison to cobalt samples without graphene, direct contact cobalt-on-graphene exhibits increased FMR linewidthan often used signature of spin pumping. Similar results are obtained in Co/MgO/graphene structures, where a 1?nm MgO layer acts as a tunnel barrier. However, magnetometry, magnetic force microscopy, and Kerr microscopy measurements demonstrate increased magnetic disorder in cobalt grown on graphene, perhaps due to changes in the growth process and an increase in defects. This magnetic disorder may account for the observed linewidth enhancement due to effects such as two-magnon scattering or mosaicity. As such, it is not possible to conclude successful spin injection into graphene from FMR linewidth measurements alone.

  15. Magnetic tweezers with high permeability electromagnets for fast actuation of magnetic beads

    SciTech Connect (OSTI)

    Chen, La; Offenhusser, Andreas; Krause, Hans-Joachim

    2015-04-15

    As a powerful and versatile scientific instrument, magnetic tweezers have been widely used in biophysical research areas, such as mechanical cell properties and single molecule manipulation. If one wants to steer bead position, the nonlinearity of magnetic properties and the strong position dependence of the magnetic field in most magnetic tweezers lead to quite a challenge in their control. In this article, we report multi-pole electromagnetic tweezers with high permeability cores yielding high force output, good maneuverability, and flexible design. For modeling, we adopted a piece-wise linear dependence of magnetization on field to characterize the magnetic beads. We implemented a bi-linear interpolation of magnetic field in the work space, based on a lookup table obtained from finite element simulation. The electronics and software were custom-made to achieve high performance. In addition, the effects of dimension and defect on structure of magnetic tips also were inspected. In a workspace with size of 0.1 0.1 mm{sup 2}, a force of up to 400 pN can be applied on a 2.8 ?m superparamagnetic bead in any direction within the plane. Because the magnetic particle is always pulled towards a tip, the pulling forces from the pole tips have to be well balanced in order to achieve control of the particles position. Active video tracking based feedback control is implemented, which is able to work at a speed of up to 1 kHz, yielding good maneuverability of the magnetic beads.

  16. Brushed permanent magnet DC MLC motor operation in an external magnetic field

    SciTech Connect (OSTI)

    Yun, J.; St Aubin, J.; Rathee, S.; Fallone, B. G.

    2010-05-15

    Purpose: Linac-MR systems for real-time image-guided radiotherapy will utilize the multileaf collimators (MLCs) to perform conformal radiotherapy and tumor tracking. The MLCs would be exposed to the external fringe magnetic fields of the linac-MR hybrid systems. Therefore, an experimental investigation of the effect of an external magnetic field on the brushed permanent magnet DC motors used in some MLC systems was performed. Methods: The changes in motor speed and current were measured for varying external magnetic field strengths up to 2000 G generated by an EEV electromagnet. These changes in motor characteristics were measured for three orientations of the motor in the external magnetic field, mimicking changes in motor orientations due to installation and/or collimator rotations. In addition, the functionality of the associated magnetic motor encoder was tested. The tested motors are used with the Varian 120 leaf Millennium MLC (Maxon Motor half leaf and full leaf motors) and the Varian 52 leaf MKII MLC (MicroMo Electronics leaf motor) including a carriage motor (MicroMo Electronics). Results: In most cases, the magnetic encoder of the motors failed prior to any damage to the gearbox or the permanent magnet motor itself. This sets an upper limit of the external magnetic field strength on the motor function. The measured limits of the external magnetic fields were found to vary by the motor type. The leaf motor used with a Varian 52 leaf MKII MLC system tolerated up to 450{+-}10 G. The carriage motor tolerated up to 2000{+-}10 G field. The motors used with the Varian 120 leaf Millennium MLC system were found to tolerate a maximum of 600{+-}10 G. Conclusions: The current Varian MLC system motors can be used for real-time image-guided radiotherapy coupled to a linac-MR system, provided the fringe magnetic fields at their locations are below the determined tolerance levels. With the fringe magnetic fields of linac-MR systems expected to be larger than the tolerance levels determined, some form of magnetic shielding would be required.

  17. Critical Magnetic Field Determination of Superconducting Materials

    SciTech Connect (OSTI)

    Canabal, A.; Tajima, T.; Dolgashev, V.A.; Tantawi, S.G.; Yamamoto, T.; /Tsukuba, Natl. Res. Lab. Metrol.

    2011-11-04

    Superconducting RF technology is becoming more and more important. With some recent cavity test results showing close to or even higher than the critical magnetic field of 170-180 mT that had been considered a limit, it is very important to develop a way to correctly measure the critical magnetic field (H{sup RF}{sub c}) of superconductors in the RF regime. Using a 11.4 GHz, 50-MW, <1 {mu}s, pulsed power source and a TE013-like mode copper cavity, we have been measuring critical magnetic fields of superconductors for accelerator cavity applications. This device can eliminate both thermal and field emission effects due to a short pulse and no electric field at the sample surface. A model of the system is presented in this paper along with a discussion of preliminary experimental data.

  18. Spectral line broadening in magnetized black holes

    SciTech Connect (OSTI)

    Frolov, Valeri P.; Shoom, Andrey A.; Tzounis, Christos E-mail: ashoom@ualberta.ca

    2014-07-01

    We consider weakly magnetized non-rotating black holes. In the presence of a regular magnetic field the motion of charged particles in the vicinity of a black hole is modified. As a result, the position of the innermost stable circular orbit (ISCO) becomes closer to the horizon. When the Lorentz force is repulsive (directed from the black hole) the ISCO radius can reach the gravitational radius. In the process of accretion charged particles (ions) of the accreting matter can be accumulated near their ISCO, while neutral particles fall down to the black hole after they reach 6M radius. The sharp spectral line Fe α, emitted by iron ions at such orbits, is broadened when the emission is registered by a distant observer. In this paper we study this broadening effect and discuss how one can extract information concerning the strength of the magnetic field from the observed spectrum.

  19. The superconducting solenoid magnets for MICE

    SciTech Connect (OSTI)

    Green, Michael A.

    2002-12-22

    The Muon Ionization Cooling Experiment (MICE) is a channel of superconducting solenoid magnets. The magnets in MICE are around the RF cavities, absorbers (liquid or solid) and the primary particle detectors [1], [2]. The MICE superconducting solenoid system consists of eighteen coils that are grouped in three types of magnet assemblies. The cooling channel consists of two complete cell of an SFOFO cooling channel. Each cell consists of a focusing coil pair around an absorber and a coupling coil around a RF cavity that re-accelerates the muons to their original momentum. At the ends of the experiment are uniform field solenoids for the particle detectors and a set of matching coils used to match the muon beam to the cooling cells. Three absorbers are used instead of two in order to shield the detectors from dark currents generated by the RF cavities at high operating acceleration gradients.

  20. Demagnetization using a determined estimated magnetic state

    DOE Patents [OSTI]

    Denis, Ronald J; Makowski, Nathanael J

    2015-01-13

    A method for demagnetizing comprising positioning a core within the electromagnetic field generated by a first winding until the generated first electrical current is not substantially increasing, thereby determining a saturation current. A second voltage, having the opposite polarity, is then applied across the first winding until the generated second electrical current is approximately equal to the magnitude of the determined saturation current. The maximum magnetic flux within the core is then determined using the voltage across said first winding and the second current. A third voltage, having the opposite polarity, is then applied across the first winding until the core has a magnetic flux equal to approximately half of the determined maximum magnetic flux within the core.

  1. Transformer current sensor for superconducting magnetic coils

    DOE Patents [OSTI]

    Shen, Stewart S.; Wilson, C. Thomas

    1988-01-01

    A transformer current sensor having primary turns carrying a primary current for a superconducting coil and secondary turns only partially arranged within the primary turns. The secondary turns include an active winding disposed within the primary turns and a dummy winding which is not disposed in the primary turns and so does not experience a magnetic field due to a flow of current in the primary turns. The active and dummy windings are wound in opposite directions or connected in series-bucking relationship, and are exposed to the same ambient magnetic field. Voltages which might otherwise develop in the active and dummy windings due to ambient magnetic fields thus cancel out. The resultant voltage is purely indicative of the rate of change of current flowing in the primary turns.

  2. Atomization methods for forming magnet powders

    DOE Patents [OSTI]

    Sellers, Charles H.; Branagan, Daniel J.; Hyde, Timothy A.

    2000-01-01

    The invention encompasses methods of utilizing atomization, methods for forming magnet powders, methods for forming magnets, and methods for forming bonded magnets. The invention further encompasses methods for simulating atomization conditions. In one aspect, the invention includes an atomization method for forming a magnet powder comprising: a) forming a melt comprising R.sub.2.1 Q.sub.13.9 B.sub.1, Z and X, wherein R is a rare earth element; X is an element selected from the group consisting of carbon, nitrogen, oxygen and mixtures thereof; Q is an element selected from the group consisting of Fe, Co and mixtures thereof; and Z is an element selected from the group consisting of Ti, Zr, Hf and mixtures thereof; b) atomizing the melt to form generally spherical alloy powder granules having an internal structure comprising at least one of a substantially amorphous phase or a substantially nanocrystalline phase; and c) heat treating the alloy powder to increase an energy product of the alloy powder; after the heat treatment, the alloy powder comprising an energy product of at least 10 MGOe. In another aspect, the invention includes a magnet comprising R, Q, B, Z and X, wherein R is a rare earth element; X is an element selected from the group consisting of carbon, nitrogen, oxygen and mixtures thereof; Q is an element selected from the group consisting of Fe, Co and mixtures thereof; and Z is an element selected from the group consisting of Ti, Zr, Hf and mixtures thereof; the magnet comprising an internal structure comprising R.sub.2.1 Q.sub.13.9 B.sub.1.

  3. Electronic structure, magnetic properties, and magnetostructural transition

    Office of Scientific and Technical Information (OSTI)

    in Tb5Si2.2Ge1.8 from first principles (Journal Article) | DOE PAGES Publisher's Accepted Manuscript: Electronic structure, magnetic properties, and magnetostructural transition in Tb5Si2.2Ge1.8 from first principles Title: Electronic structure, magnetic properties, and magnetostructural transition in Tb5Si2.2Ge1.8 from first principles Authors: Paudyal, Durga ; Mudryk, Y. ; Pecharsky, V. K. ; Gschneidner, K. A. Publication Date: 2011-07-27 OSTI Identifier: 1100399 Type: Publisher's Accepted

  4. Electronic structure, magnetic properties, and magnetostructural transition

    Office of Scientific and Technical Information (OSTI)

    in Tb5Si2.2Ge1.8 from first principles (Journal Article) | SciTech Connect Electronic structure, magnetic properties, and magnetostructural transition in Tb5Si2.2Ge1.8 from first principles Citation Details In-Document Search Title: Electronic structure, magnetic properties, and magnetostructural transition in Tb5Si2.2Ge1.8 from first principles Authors: Paudyal, Durga ; Mudryk, Y. ; Pecharsky, V. K. ; Gschneidner, K. A. Publication Date: 2011-07-27 OSTI Identifier: 1100399 Type: Publisher's

  5. Diluted magnetic semiconductor nanowires exhibiting magnetoresistance

    DOE Patents [OSTI]

    Yang, Peidong (El Cerrito, CA); Choi, Heonjin (Seoul, KR); Lee, Sangkwon (Daejeon, KR); He, Rongrui (Albany, CA); Zhang, Yanfeng (El Cerrito, CA); Kuykendal, Tevye (Berkeley, CA); Pauzauskie, Peter (Berkeley, CA)

    2011-08-23

    A method for is disclosed for fabricating diluted magnetic semiconductor (DMS) nanowires by providing a catalyst-coated substrate and subjecting at least a portion of the substrate to a semiconductor, and dopant via chloride-based vapor transport to synthesize the nanowires. Using this novel chloride-based chemical vapor transport process, single crystalline diluted magnetic semiconductor nanowires Ga.sub.1-xMn.sub.xN (x=0.07) were synthesized. The nanowires, which have diameters of .about.10 nm to 100 nm and lengths of up to tens of micrometers, show ferromagnetism with Curie temperature above room temperature, and magnetoresistance up to 250 Kelvin.

  6. High performance hybrid magnetic structure for biotechnology applications

    DOE Patents [OSTI]

    Humphries, David E. (El Cerrito, CA); Pollard, Martin J. (El Cerrito, CA); Elkin, Christopher J. (San Ramon, CA)

    2009-02-03

    The present disclosure provides a high performance hybrid magnetic structure made from a combination of permanent magnets and ferromagnetic pole materials which are assembled in a predetermined array. The hybrid magnetic structure provides means for separation and other biotechnology applications involving holding, manipulation, or separation of magnetic or magnetizable molecular structures and targets. Also disclosed are further improvements to aspects of the hybrid magnetic structure, including additional elements and for adapting the use of the hybrid magnetic structure for use in biotechnology and high throughput processes.

  7. High performance hybrid magnetic structure for biotechnology applications

    DOE Patents [OSTI]

    Humphries, David E; Pollard, Martin J; Elkin, Christopher J

    2005-10-11

    The present disclosure provides a high performance hybrid magnetic structure made from a combination of permanent magnets and ferromagnetic pole materials which are assembled in a predetermined array. The hybrid magnetic structure provides means for separation and other biotechnology applications involving holding, manipulation, or separation of magnetizable molecular structures and targets. Also disclosed are: a method of assembling the hybrid magnetic plates, a high throughput protocol featuring the hybrid magnetic structure, and other embodiments of the ferromagnetic pole shape, attachment and adapter interfaces for adapting the use of the hybrid magnetic structure for use with liquid handling and other robots for use in high throughput processes.

  8. Noise-cancelling quadrature magnetic position, speed and direction sensor

    DOE Patents [OSTI]

    Preston, Mark A. (Niskayuna, NY); King, Robert D. (Schenectady, NY)

    1996-01-01

    An array of three magnetic sensors in a single package is employed with a single bias magnet for sensing shaft position, speed and direction of a motor in a high magnetic noise environment. Two of the three magnetic sensors are situated in an anti-phase relationship (i.e., 180.degree. out-of-phase) with respect to the relationship between the other of the two sensors and magnetically salient target, and the third magnetic sensor is situated between the anti-phase sensors. The result is quadrature sensing with noise immunity for accurate relative position, speed and direction measurements.

  9. The Use of Small Coolers in a Magnetic Field

    SciTech Connect (OSTI)

    Green, Michael A.; Witte, Holger

    2007-07-25

    Small 4 K coolers are used to cool superconducting magnets.These coolers are usually used with high temperature suerconductor (HTS)leads. In most cases, magnet is shielded with iron or active shieldcoils. Thus the field at the cooler is low. There are instances when thecooler must be in a magnetic field. Gifford McMahon (GM) coolers or pulsetube coolers are commercially available to cool the magnets. This paperwill discuss how the two types of coolers are affected by the straymagnetic field. Strategies for using coolers on magnets that generatestray magnetic fields are discussed.

  10. Batch extracting process using magnetic particle held solvents

    DOE Patents [OSTI]

    Nunez, L.; Vandergrift, G.F.

    1995-11-21

    A process is described for selectively removing metal values which may include catalytic values from a mixture containing same, wherein a magnetic particle is contacted with a liquid solvent which selectively dissolves the metal values to absorb the liquid solvent onto the magnetic particle. Thereafter the solvent-containing magnetic particles are contacted with a mixture containing the heavy metal values to transfer metal values into the solvent carried by the magnetic particles, and then magnetically separating the magnetic particles. Ion exchange resins may be used for selective solvents. 5 figs.

  11. Enhanced magnetic hysteresis in Ni-Mn-Ga single crystal and its influence on magnetic shape memory effect

    SciTech Connect (OSTI)

    Heczko, O. Drahokoupil, J.; Straka, L.

    2015-05-07

    Enhanced magnetic hysteresis due to boron doping in combination with magnetic shape memory effect in Ni-Mn-Ga single crystal results in new interesting functionality of magnetic shape memory (MSM) alloys such as mechanical demagnetization. In Ni{sub 50.0}Mn{sub 28.5}Ga{sub 21.5} single crystal, the boron doping increased magnetic coercivity from few Oe to 270?Oe while not affecting the transformation behavior and 10?M martensite structure. However, the magnetic field needed for MSM effect also increased in doped sample. The magnetic behavior is compared to undoped single crystal of similar composition. The evidence from the X-ray diffraction, magnetic domain structure, magnetization loops, and temperature evolution of the magnetic coercivity points out that the enhanced hysteresis is caused by stress-induced anisotropy.

  12. Magnetic switching behaviors of orbital states with different magnetic quantum numbers in Au/Fe/MgO multilayer system

    SciTech Connect (OSTI)

    Suzuki, Kosuke Takubo, Shota; Kato, Tadashi; Yamazoe, Masatoshi; Hoshi, Kazushi; Sakurai, Hiroshi; Homma, Yoshiya; Itou, Masayoshi; Sakurai, Yoshiharu

    2014-08-18

    A spin specific magnetic hysteresis (SSMH) curve and an orbital specific magnetic hysteresis (OSMH) curve are obtained for Fe/Au/Fe/MgO multilayers by magnetic Compton scattering and SQUID magnetometer measurements. The SSMH curve with each contribution of magnetic quantum number |m| = 0, 1, and 2 states is obtained by decomposition analyses of magnetic Compton profiles. Residual magnetization is observed for the SSMH curve with magnetic quantum number |m| = 0, 2 and the OSMH curve. Although the SQUID magnetometer measurements do not show perpendicular magnetic anisotropy (PMA) in the present Fe/Au/Fe/MgO multilayer film, the SSMH curve with magnetic quantum number |m| = 0, 2 and OSMH curve show switching behaviors of PMA.

  13. CaMn2Al10: Itinerant Mn magnetism on the verge of magnetic order

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

    Steinke, L.; Simonson, J. W.; Yin, W. -G.; Smith, G. J.; Kistner-Morris, J. J.; Zellman, S.; Puri, A.; Aronson, M. C.

    2015-07-24

    We report the discovery of CaMn2Al10, a metal with strong magnetic anisotropy and moderate electronic correlations. Magnetization measurements find a Curie-Weiss moment of 0.83μB/Mn, significantly reduced from the Hund's rule value, and the magnetic entropy obtained from specific heat measurements is correspondingly small, only ≈ 9% of Rln2. These results imply that the Mn magnetism is highly itinerant, a conclusion supported by density functional theory calculations that find strong Mn-Al hybridization. Consistent with the layered nature of the crystal structure, the magnetic susceptibility χ is anisotropic below 20 K, with a maximum ratio of χ[010]/χ[001] ≈ 3.5. A strong power-lawmore » divergence χ(T) ~ T–1.2 below 20 K implies incipient ferromagnetic order, an Arrott plot analysis of the magnetization suggests a vanishing low Curie temperature TC ~ 0. Our experiments indicate that CaMn2Al10 is a rare example of a system where the weak and itinerant Mn-based magnetism is poised on the verge of order.« less

  14. The largest and highest powered magnet lab in the world - MagLab

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

    Magnet Time Search Staff Search Publications Search Site The National High Magnetic Field Laboratory Main Menu User Facilities DC Field Electron Magnetic Resonance High BT Ion...

  15. Spintronic transport of a non-magnetic molecule between magnetic electrodes

    SciTech Connect (OSTI)

    Kondo, Hisashi; Ohno, Takahisa; Institute of Industrial Science, University of Tokyo, Meguro, Tokyo 153-8505

    2013-12-02

    The spintronic transport properties of a junction system composed of a non-magnetic molecule sandwiched between ferromagnetic metal electrodes are investigated theoretically using a non-equilibrium Green's function method based on density functional theory. It is revealed that in such a system, the molecular magnetic properties induced by hybridization with the magnetic electrodes play a crucial role. Alignment of the induced molecular spin-split levels is strongly related to the spin injection and tunneling magneto-resistance effects. It is found that in the system with weaker molecule-electrode interaction, stronger spintronic effects of the spin injection and tunneling magneto-resistance are observed.

  16. Effect of Side Permanent Magnets for Reluctance Interior Permanent Magnet Reluctance Machines

    SciTech Connect (OSTI)

    Hsu, John S; Lee, Seong T; Wiles, Randy H; Coomer, Chester; Lowe, Kirk T

    2007-01-01

    A traditional electric machine uses two dimensional magnetic flux paths in its rotor. This paper presents the development work on the utilization of the third dimension of a rotor. As an example, the air gap flux of a radial gap interior permanent magnet motor can be significantly enhanced by additional permanent magnets (PM) mounted at the sides of the rotor. A prototype motor built with this concept provided higher efficiency and required a shorter stator core length for the same power output as the Toyota/Prius traction drive motor.

  17. Magnetic agglomeration method for size control in the synthesis of magnetic nanoparticles

    DOE Patents [OSTI]

    Huber, Dale L. (Albuquerque, NM)

    2011-07-05

    A method for controlling the size of chemically synthesized magnetic nanoparticles that employs magnetic interaction between particles to control particle size and does not rely on conventional kinetic control of the reaction to control particle size. The particles are caused to reversibly agglomerate and precipitate from solution; the size at which this occurs can be well controlled to provide a very narrow particle size distribution. The size of particles is controllable by the size of the surfactant employed in the process; controlling the size of the surfactant allows magnetic control of the agglomeration and precipitation processes. Agglomeration is used to effectively stop particle growth to provide a very narrow range of particle sizes.

  18. Determining the exchange parameters of spin-1 metal-organic molecular magnets in pulsed magnetic fields

    SciTech Connect (OSTI)

    Mcdonald, Ross D; Singleton, John; Lancaster, Tom; Goddard, Paul; Manson, Jamie

    2011-01-14

    We nave measured the high-field magnetization of a number of Ni-based metal-organic molecular magnets. These materials are self-assembly coordination polymers formed from transition metal ions and organic ligands. The chemistry of the compounds is versatile allowing many structures with different magnetic properties to be formed. These studies follow on from previous measurements of the Cu-based analogues in which we showed it was possible to extract the exchange parameters of low-dimensional magnets using pulsed magnetic fields. In our recent experiments we have investigated the compound (Ni(HF{sub 2})(pyz){sub 2})PF{sub 6}, where pyz = pyrazine, and the Ni-ions are linked in a quasi-two-dimensional (Q2D) square lattice via the pyrazine molecules, with the layers held together by HF{sub 2} ligands. We also investigated Ni(NCS){sub 2}(pyzdo){sub 2}, where pyzdo = pyrazine dioxide. The samples are grown at Eastern Washington University using techniques described elsewhere. Measurements are performed at the pulsed magnetic field laboratory in Los Alamos. The magnetization of powdered samples is determined using a compensated coil magnetometer in a 65 T short pulse magnet. Temperatures as low as 500 mK are achievable using a {sup 3}He cryostat. The main figure shows the magnetization of the spin-1 [Ni(HF{sub 2})(pyz){sub 2}]PF{sub 6} compound at 1.43 K. The magnetization rises slowly at first, achieving a rounded saturation whose midpoint is around 19 T. A small anomaly is also seen in the susceptibility at low fields ({approx}3 T), which might be attributed to a spin-flop transition. In contrast, the spin-1/2 [Cu(HF{sub 2})(pyz){sub 2}]PF{sub 6} measured previously has a saturation magnetization of 35.5 T and a strongly concave form of M(B) below this field. This latter compound was shown to be a good example of a Q2D Heisenberg antiferromagnet with the strong exchange coupling (J{sub 2D} = 12.4 K, J{sub {perpendicular}}/J{sub 2D} {approx} 10{sup -2}) directed along the Cu-pyz-Cu directions. The structure of the two compounds is similar, but in the case of the Cu-compound the Cu-Cu pathways are linear, whereas in the Ni-compound they are kinked. The pulsed-field data combined with information from temperature-dependent susceptibility, muon-spin rotation, electron-spin resonance and ligand-field calculations suggest that, far from being magnetically Q2D, the Ni-compound is fairly one-dimensional with the dominant exchange (J{sub 1D} = 3.1 K and J{sub {perpendicular}}/J{sub 1D} = 0.63) directed along the Ni-FHF-Ni direction. Ni(NCS){sub 2}(pyzdo){sub 2} was also investigated. Previous ultra-high field measurements using the 100 T magnet have shown that this compound has a saturation field close to 80 T. The purpose of the present studies is to map out the phase diagram of this material at mid-range fields. The data are shown in the inset to the figure. This continuing project probes the ability of organic ligands to mediate magnetic exchange, the link between structure, dimensionality and bulk magnetic properties, as well as the role of spin number in quantum magnets. Ultimately the investigations aim to determine to what extent it is possible to produce self-assembly molecular materials with tailor-made magnetic characteristics.

  19. Charm production in a strong magnetic field

    SciTech Connect (OSTI)

    Machado, C. S.; Navarra, F. S.; Noronha, J.; Oliveira, E. G. de; Strickland, M.

    2014-11-11

    We discuss the effects of a strong magnetic field on B and D mesons, focusing on the changes of the energy levels and the masses of the bound states. Using the Color Evaporation Model we discuss the possible changes in the production of J/? and ?. We briefly comment the recent experimental data.

  20. Magnetically excited flexural plate wave apparatus

    DOE Patents [OSTI]

    Martin, S.J.; Butler, M.A.; Frye, G.C.; Smith, J.H.

    1998-11-17

    A non-piezoelectric flexural plate wave apparatus having meander-line transducers mounted on a non-piezoelectric membrane is disclosed. A static magnetic field is directed perpendicularly to the conductive legs of the transducers in the plane of the membrane. Single-port, two-port, resonant, non-resonant, eigenmode, and delay-line modes may be employed. 15 figs.

  1. Magnetically excited flexural plate wave apparatus

    DOE Patents [OSTI]

    Martin, Stephen J.; Butler, Michael A.; Frye, Gregory C.; Smith, James H.

    1998-01-01

    A non-piezoelectric flexural plate wave apparatus having meander-line transducers mounted on a non-piezoelectric membrane. A static magnetic field is directed perpendicularly to the conductive legs of the transducers in the plane of the membrane. Single-port, two-port, resonant, non-resonant, eigenmode, and delay-line modes may be employed.

  2. Magnetic fields and galactic star formation rates

    SciTech Connect (OSTI)

    Loo, Sven Van; Tan, Jonathan C.; Falle, Sam A. E. G.

    2015-02-10

    The regulation of galactic-scale star formation rates (SFRs) is a basic problem for theories of galaxy formation and evolution: which processes are responsible for making observed star formation rates so inefficient compared to maximal rates of gas content divided by dynamical timescale? Here we study the effect of magnetic fields of different strengths on the evolution of giant molecular clouds (GMCs) within a kiloparsec patch of a disk galaxy and resolving scales down to ?0.5 pc. Including an empirically motivated prescription for star formation from dense gas (n{sub H}>10{sup 5} cm{sup ?3}) at an efficiency of 2% per local free-fall time, we derive the amount of suppression of star formation by magnetic fields compared to the nonmagnetized case. We find GMC fragmentation, dense clump formation, and SFR can be significantly affected by the inclusion of magnetic fields, especially in our strongest investigated B-field case of 80 ?G. However, our chosen kiloparsec-scale region, extracted from a global galaxy simulation, happens to contain a starbursting cloud complex that is only modestly affected by these magnetic fields and likely requires internal star formation feedback to regulate its SFR.

  3. Magnetic and charge ordering in nanosized manganites

    SciTech Connect (OSTI)

    Zhang, T. Wang, X. P.; Fang, Q. F.; Li, X. G.

    2014-09-15

    Perovskite manganites exhibit a wide range of functional properties, such as colossal magneto-resistance, magnetocaloric effect, multiferroic property, and some interesting physical phenomena including spin, charge, and orbital ordering. Recent advances in science and technology associated with perovskite oxides have resulted in the feature sizes of microelectronic devices down-scaling into nanoscale dimensions. The nanoscale perovskite manganites display novel magnetic and electronic properties that are different from their bulk and film counterparts. Understanding the size effects of perovskite manganites at the nanoscale is of importance not only for the fundamental scientific research but also for developing next generation of electronic and magnetic nanodevices. In this paper, the current understanding and the fundamental issues related to the size effects on the magnetic properties and charge ordering in manganites are reviewed, which covers lattice structure, magnetic and electronic properties in both ferromagnetic and antiferromagnetic based manganites. In addition to review the literatures, this article identifies the promising avenues for the future research in this area.

  4. VINETA II: A linear magnetic reconnection experiment

    SciTech Connect (OSTI)

    Bohlin, H. Von Stechow, A.; Rahbarnia, K.; Grulke, O.; Klinger, T.; Ernst-Moritz-Arndt University, Domstr. 11, 17489 Greifswald

    2014-02-15

    A linear experiment dedicated to the study of driven magnetic reconnection is presented. The new device (VINETA II) is suitable for investigating both collisional and near collisionless reconnection. Reconnection is achieved by externally driving magnetic field lines towards an X-point, inducing a current in the background plasma which consequently modifies the magnetic field topology. Owing to the open field line configuration of the experiment, the current is limited by the axial sheath boundary conditions. A plasma gun is used as an additional electron source in order to counterbalance the charge separation effects and supply the required current. Two drive methods are used in the device. First, an oscillating current through two parallel conductors drive the reconnection. Second, a stationary X-point topology is formed by the parallel conductors, and the drive is achieved by an oscillating current through a third conductor. In the first setup, the magnetic field of the axial plasma current dominates the field topology near the X-point throughout most of the drive. The second setup allows for the amplitude of the plasma current as well as the motion of the flux to be set independently of the X-point topology of the parallel conductors.

  5. Passive levitation in alternating magnetic fields

    DOE Patents [OSTI]

    Romero, Louis (Albuquerque, NM); Christenson, Todd (Albuquerque, NM); Aronson, Eugene A. (Albuquerque, NM)

    2009-06-16

    Stable levitation of an object in an alternating magnetic field can be achieved by eliminating coupling between the rotational and translational forces acting on the object. Stable levitation can also be achieved by varying the coupling between the rotational and translational forces acting on the object, while maintaining one or more of the rotational and translational forces steady in time.

  6. Passive levitation in alternating magnetic fields

    DOE Patents [OSTI]

    Romero, Louis (Albuquerque, NM); Christenson, Todd (Albuquerque, NM); Aronson, Eugene A. (Albuquerque, NM)

    2010-09-14

    Stable levitation of an object in an alternating magnetic field can be achieved by eliminating coupling between the rotational and translational forces acting on the object. Stable levitation can also be achieved by varying the coupling between the rotational and translational forces acting on the object, while maintaining one or more of the rotational and translational forces steady in time.

  7. A TOMOGRAPHIC TECHNIQUE FOR MAGNETIZED BEAM MATCHING.

    SciTech Connect (OSTI)

    MONTAG,C.ET AL.

    2004-07-05

    To maintain low electron beam temperatures in the proposed RHIC electron cooler, careful matching of the magnetized beam from the source to the cooler solenoid is mandatory. We propose a tomographic technique to diagnose matching conditions. First simulation results will be presented.

  8. Basics and prospective of magnetic Heusler compounds

    SciTech Connect (OSTI)

    Felser, Claudia Wollmann, Lukas; Chadov, Stanislav; Fecher, Gerhard H.; Parkin, Stuart S. P.

    2015-04-01

    Heusler compounds are a remarkable class of materials with more than 1000 members and a wide range of extraordinary multi-functionalities including halfmetallic high-temperature ferri- and ferromagnets, multi-ferroics, shape memory alloys, and tunable topological insulators with a high potential for spintronics, energy technologies, and magneto-caloric applications. The tunability of this class of materials is exceptional and nearly every functionality can be designed. Co{sub 2}-Heusler compounds show high spin polarization in tunnel junction devices and spin-resolved photoemission. Manganese-rich Heusler compounds attract much interest in the context of spin transfer torque, spin Hall effect, and rare earth free hard magnets. Most Mn{sub 2}-Heusler compounds crystallize in the inverse structure and are characterized by antiparallel coupling of magnetic moments on Mn atoms; the ferrimagnetic order and the lack of inversion symmetry lead to the emergence of new properties that are absent in ferromagnetic centrosymmetric Heusler structures, such as non-collinear magnetism, topological Hall effect, and skyrmions. Tetragonal Heusler compounds with large magneto crystalline anisotropy can be easily designed by positioning the Fermi energy at the van Hove singularity in one of the spin channels. Here, we give a comprehensive overview and a prospective on the magnetic properties of Heusler materials.

  9. Magnetic mesoporous material for the sequestration of algae

    DOE Patents [OSTI]

    Trewyn, Brian G.; Kandel, Kapil; Slowing, Igor Ivan; Lee, Show-Ling

    2014-09-09

    The present invention provides a magnetic mesoporous nanoparticle that includes a mesoporous silicate nanoparticle and iron oxide. The present invention also provides a method of using magnetic mesoporous nanoparticles to sequester microorganisms from a media.

  10. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    onoff). For magnetic media, binary digits (bits) have historically taken the form of grains of magnetic material in which all the spins are aligned. As we increase the number of...

  11. Deuterium Uptake in Magnetic Fusion Devices with Lithium Conditioned Carbon

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

    Walls | Princeton Plasma Physics Lab Deuterium Uptake in Magnetic Fusion Devices with Lithium Conditioned Carbon Walls American Fusion News Category: U.S. Universities Link: Deuterium Uptake in Magnetic Fusion Devices with Lithium Conditioned Carbon Walls

  12. X-Ray Diffraction Microscopy of Magnetic Structures

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

    Lensless Imaging of Magnetic Nanostructures Work performed on ALS Beamline 12.0.2.2 Citation: J.J. Turner et al., "X-Ray Diffraction Microscopy of Magnetic Structures," Phys....

  13. Magnetism and superconductivity observed to exist in harmony

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

    and helium. "It's really a question of the chicken and the egg," said coauthor Eric Bauer of Los Alamos. "Does superconductivity need magnetism in this state, or does magnetism...

  14. Imaging exotic properties of nanoscale magnetic lattices | Argonne...

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

    of Energy's Office of Basic Energy Sciences, we have shown the signature of magnetic induction associated with a "magnetic monopole" defect for the first time. Some of the most...

  15. Iron-Nitride Alloy Magnets: Transformation Enabled Nitride Magnets Absent Rare Earths (TEN Mare)

    SciTech Connect (OSTI)

    2012-01-01

    REACT Project: Case Western is developing a highly magnetic iron-nitride alloy to use in the magnets that power electric motors found in EVs and renewable power generators. This would reduce the overall price of the motor by eliminating the expensive imported rare earth minerals typically found in todays best commercial magnets. The iron-nitride powder is sourced from abundant and inexpensive materials found in the U.S. The ultimate goal of this project is to demonstrate this new magnet system, which contains no rare earths, in a prototype electric motor. This could significantly reduce the amount of greenhouse gases emitted in the U.S. each year by encouraging the use of clean alternatives to oil and coal.

  16. In-plane electric fields in magnetic islands during collisionless magnetic reconnection

    SciTech Connect (OSTI)

    Chen Lijen; Bhattacharjee, Amitava; Torbert, Roy B.; Bessho, Naoki; Daughton, William; Roytershteyn, Vadim

    2012-11-15

    Magnetic islands are a common feature in both the onset and nonlinear evolution of magnetic reconnection. In collisionless regimes, the onset typically occurs within ion-scale current layers leading to the formation of magnetic islands when multiple X lines are involved. The nonlinear evolution of reconnection often gives rise to extended electron current layers (ECL) which are also unstable to formation of magnetic islands. Here, we show that the excess negative charge and strong out-of-plane electron velocity in the ECL are passed on to the islands generated therein, and that the corresponding observable distinguishing the islands generated in the ECL is the strongly enhanced in-plane electric fields near the island core. The islands formed in ion-scale current layers do not have these properties of the ECL-generated islands. The above result provides a way to assess the occurrence and importance of extended ECLs that are unstable to island formation in space and laboratory plasmas.

  17. Conversion of magnetic energy in the magnetic reconnection layer of a laboratory plasma

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

    Yamada, Masaaki; Yoo, Jongsoo; Jara-Almonte, Jonathan; Ji, Hantao; Kulsrud, Russell M.; Myers, Clayton E.

    2014-09-10

    Magnetic reconnection, in which magnetic field lines break and reconnect to change their topology, occurs throughout the universe. The essential feature of reconnection is that it energizes plasma particles by converting magnetic energy. Despite the long history of reconnection research, how this energy conversion occurs remains a major unresolved problem in plasma physics. Here we report that the energy conversion in a laboratory reconnection layer occurs in a much larger region than previously considered. The mechanisms for energizing plasma particles in the reconnection layer are identified, and a quantitative inventory of the converted energy is presented for the first timemore » in a well defined reconnection layer; 50% of the magnetic energy is converted to particle energy, 2/3 of which transferred to ions and 1/3 to electrons. Our results are compared with simulations and space measurements, for a key step toward resolving one of the most important problems in plasma physics.« less

  18. Conversion of magnetic energy in the magnetic reconnection layer of a laboratory plasma

    SciTech Connect (OSTI)

    Yamada, Masaaki; Yoo, Jongsoo; Jara-Almonte, Jonathan; Ji, Hantao; Kulsrud, Russell M.; Myers, Clayton E.

    2014-09-10

    Magnetic reconnection, in which magnetic field lines break and reconnect to change their topology, occurs throughout the universe. The essential feature of reconnection is that it energizes plasma particles by converting magnetic energy. Despite the long history of reconnection research, how this energy conversion occurs remains a major unresolved problem in plasma physics. Here we report that the energy conversion in a laboratory reconnection layer occurs in a much larger region than previously considered. The mechanisms for energizing plasma particles in the reconnection layer are identified, and a quantitative inventory of the converted energy is presented for the first time in a well defined reconnection layer; 50% of the magnetic energy is converted to particle energy, 2/3 of which transferred to ions and 1/3 to electrons. Our results are compared with simulations and space measurements, for a key step toward resolving one of the most important problems in plasma physics.

  19. Manganese-Based Magnets: Manganese-Based Permanent Magnet with 40 MGOe at 200C

    SciTech Connect (OSTI)

    2012-01-01

    REACT Project: PNNL is working to reduce the cost of wind turbines and EVs by developing a manganese-based nano-composite magnet that could serve as an inexpensive alternative to rare-earth-based magnets. The manganese composite, made from low-cost and abundant materials, could exceed the performance of todays most powerful commercial magnets at temperature higher than 200C. Members of PNNLs research team will leverage comprehensive computer high-performance supercomputer modeling and materials testing to meet this objective. Manganese-based magnets could withstand higher temperatures than their rare earth predecessors and potentially reduce the need for any expensive, bulky engine cooling systems for the motor and generator. This would further contribute to cost savings for both EVs and wind turbines.

  20. International magnetic pulse compression workshop: (Proceedings)

    SciTech Connect (OSTI)

    Kirbie, H.C.; Newton, M.A.; Siemens, P.D.

    1991-04-01

    A few individuals have tried to broaden the understanding of specific and salient pulsed-power topics. One such attempt is this documentation of a workshop on magnetic switching as it applies primarily to pulse compression (power transformation), affording a truly international perspective by its participants under the initiative and leadership of Hugh Kirbie and Mark Newton of the Lawrence Livermore National Laboratory (LLNL) and supported by other interested organizations. During the course of the Workshop at Granlibakken, a great deal of information was amassed and a keen insight into both the problems and opportunities as to the use of this switching approach was developed. The segmented workshop format proved ideal for identifying key aspects affecting optimum performance in a variety of applications. Individual groups of experts addressed network and system modeling, magnetic materials, power conditioning, core cooling and dielectrics, and finally circuits and application. At the end, they came together to consolidate their input and formulate the workshop's conclusions, identifying roadblocks or suggesting research projects, particularly as they apply to magnetic switching's trump card--its high-average-power-handling capability (at least on a burst-mode basis). The workshop was especially productive both in the quality and quantity of information transfer in an environment conducive to a free and open exchange of ideas. We will not delve into the organization proper of this meeting, rather we wish to commend to the interested reader this volume, which provides the definitive and most up-to-date compilation on the subject of magnetic pulse compression from underlying principles to current state of the art as well as the prognosis for the future of magnetic pulse compression as a consensus of the workshop's organizers and participants.