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Note: This page contains sample records for the topic "imaging current-driven magnetic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
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1

X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires  

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

X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires Print X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires Print The quest to increase both computer data-storage density and the speed at which one can read and write the information remains unconsummated. One novel concept is based on the use of a local electric current to push magnetic domain walls along a thin nanowire. A German, Korean, Berkeley Lab team has used the x-ray microscope XM-1 at the ALS to demonstrate that magnetic domain walls in curved permalloy nanowires can be moved at high speed by injecting nanosecond pulses of spin-polarized currents into the wires, but the motion is largely stochastic. This result will have an impact on the current development of magnetic storage devices in which data is moved electronically rather than mechanically as in computer disk drives.

2

X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires  

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

X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires Print X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires Print The quest to increase both computer data-storage density and the speed at which one can read and write the information remains unconsummated. One novel concept is based on the use of a local electric current to push magnetic domain walls along a thin nanowire. A German, Korean, Berkeley Lab team has used the x-ray microscope XM-1 at the ALS to demonstrate that magnetic domain walls in curved permalloy nanowires can be moved at high speed by injecting nanosecond pulses of spin-polarized currents into the wires, but the motion is largely stochastic. This result will have an impact on the current development of magnetic storage devices in which data is moved electronically rather than mechanically as in computer disk drives.

3

X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires  

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

X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires Print X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires Print The quest to increase both computer data-storage density and the speed at which one can read and write the information remains unconsummated. One novel concept is based on the use of a local electric current to push magnetic domain walls along a thin nanowire. A German, Korean, Berkeley Lab team has used the x-ray microscope XM-1 at the ALS to demonstrate that magnetic domain walls in curved permalloy nanowires can be moved at high speed by injecting nanosecond pulses of spin-polarized currents into the wires, but the motion is largely stochastic. This result will have an impact on the current development of magnetic storage devices in which data is moved electronically rather than mechanically as in computer disk drives.

4

X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires  

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

X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires Print X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires Print The quest to increase both computer data-storage density and the speed at which one can read and write the information remains unconsummated. One novel concept is based on the use of a local electric current to push magnetic domain walls along a thin nanowire. A German, Korean, Berkeley Lab team has used the x-ray microscope XM-1 at the ALS to demonstrate that magnetic domain walls in curved permalloy nanowires can be moved at high speed by injecting nanosecond pulses of spin-polarized currents into the wires, but the motion is largely stochastic. This result will have an impact on the current development of magnetic storage devices in which data is moved electronically rather than mechanically as in computer disk drives.

5

X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires  

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

X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires Print X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires Print The quest to increase both computer data-storage density and the speed at which one can read and write the information remains unconsummated. One novel concept is based on the use of a local electric current to push magnetic domain walls along a thin nanowire. A German, Korean, Berkeley Lab team has used the x-ray microscope XM-1 at the ALS to demonstrate that magnetic domain walls in curved permalloy nanowires can be moved at high speed by injecting nanosecond pulses of spin-polarized currents into the wires, but the motion is largely stochastic. This result will have an impact on the current development of magnetic storage devices in which data is moved electronically rather than mechanically as in computer disk drives.

6

X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires  

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

X-Ray Imaging Current-Driven X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires Print Wednesday, 26 September 2007 00:00 The quest to increase both computer data-storage density and the speed at which one can read and write the information remains unconsummated. One novel concept is based on the use of a local electric current to push magnetic domain walls along a thin nanowire. A German, Korean, Berkeley Lab team has used the x-ray microscope XM-1 at the ALS to demonstrate that magnetic domain walls in curved permalloy nanowires can be moved at high speed by injecting nanosecond pulses of spin-polarized currents into the wires, but the motion is largely stochastic. This result will have an impact on the current development of magnetic storage devices in which data is moved electronically rather than mechanically as in computer disk drives.

7

Current-driven instability of magnetic jets  

E-Print Network (OSTI)

MHD instabilities can be responsible for the complex morphology of astrophysical jets. We consider the stability properties of jets containing both the azimuthal and axial field of subthermal strength. The presence of the magnetic field with complex topology in jets is suggested by theoretical models and it is consistent with recent observations. Stability is discussed by means of a linear analysis of the ideal MHD equations.We argue that, in the presence of azimuthal and axial magnetic fields, the jet is always unstable to non-axisymmetric perturbations. Stabilization does not occur even if the strengths of these field components are comparable. If the axial field is weaker than the azimuthal one, instability occurs for perturbations with any azimuthal wave number $m$, and the growth rate reach a saturation value for small values of $m$. If the axial field is stronger than the toroidal one, the instability shows off for perturbations with relatively large $m$.

Bonanno, Alfio

2010-01-01T23:59:59.000Z

8

Experimental Study of Current-Driven Turbulence During Magnetic Reconnection  

SciTech Connect

CMPD Final Report Experimental Study of Current-Driven Turbulence During Magnetic Reconnection Miklos Porkolab, PI, Jan Egedal, co-PI, William Fox, graduate student. This is the final report for Grant DE-FC02-04ER54786, ?¢????MIT Participation in the Center for Multiscale Plasma Dynamics,?¢??? which was active from 8/1/2004 to 7/31/2010. This Grant supported the thesis work of one MIT graduate student, William Fox, The thesis research consisted of an experimental study of the fluctuations arising during magnetic reconnection in plasmas on the Versatile Toroidal Facility (VTF) at MIT Plasma Science and Fusion Center (PSFC). The thesis was submitted and accepted by the MIT physics Department, ?¢????W. Fox, Experimental Study of Current-Driven Turbulence During Magnetic Reconnection, Ph.D. Thesis, MIT (2009)?¢???. In the VTF experiment reconnection and current-sheet formation is driven by quickly changing currents in a specially arranged set of internal conductors. Previous work on this device [Egedal, et al, PRL 98, 015003, (2007)] identified a ?¢????spontaneous?¢??? reconnection regime. In this work fluctuations were studied using impedance-matched, high-bandwidth Langmuir probes. Strong, broadband fluctuations, with frequencies extending from near the lower-hybrid frequency [fLH = (fcefci)1/2] to the electron cyclotron frequency fce were found to arise during the reconnection events. Based on frequency and wavelength measurements, lower-hybrid waves and Trivelpiece-Gould waves were identified. The lower-hybrid waves are easiest to drive with strong perpendicular drifts or gradients which arise due to the reconnection events; an appealing possibility is strong temperature gradients. The Trivelpiece-Gould modes can result from kinetic, bump-on-tail instability of a runaway electron population energized by the reconnection events. We also observed that the turbulence is often spiky, consisting of discrete positive-potential spikes, which were identified as ?¢????electron phase-space holes,?¢??? a class of nonlinear solitary wave known to evolve from a strong beam-on-tail instability. We established that fast electrons were produced by magnetic reconnection. Overall, these instabilities were found to be a consequence of reconnection, specifically the strong energization of electrons, leading to steep gradients in both coordinate- and velocity-space. Estimates (using quasi-linear theory) of the anomalous resistivity due to these modes did not appear large enough to substantially impact the reconnection process. Relevant publications: ?¢???¢ W. Fox, M. Porkolab, et al, Phys. Rev. Lett. 101, 255003 (2008). ?¢???¢ W. Fox, M. Porkolab, et al, Phys. Plasmas 17, 072303, (2010).

Miklos Porkolab; Jan Egedal-Pedersen; William Fox

2010-08-31T23:59:59.000Z

9

Experimental study of current-driven turbulence during magnetic reconnection  

E-Print Network (OSTI)

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

Fox, William Randolph, II

2009-01-01T23:59:59.000Z

10

X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires  

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

information (0 and 1). A short pulse of electric current pushes the domains through the wire to a fixed readout sensor. Invented at IBM, racetrack memory so far has neither high...

11

Magnetic Imaging  

Science Conference Proceedings (OSTI)

... data-storage and permanent magnets with increased energy products, in ... Optimization of future materials, including improved yields, requires an ...

2012-10-02T23:59:59.000Z

12

Lensless Imaging of Magnetic Nanostructures  

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

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....

13

Lensless Imaging of Magnetic Nanostructures  

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

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....

14

Low field magnetic resonance imaging  

DOE Patents (OSTI)

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.

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

2010-07-13T23:59:59.000Z

15

Lensless Imaging of Magnetic Nanostructures  

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

Lensless Imaging of Magnetic 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 ALS's soft x-rays have enabled scientists to apply lensless x-ray imaging for the first time to nanometer-scale magnetic structures in an alloy. Many Ways To See You open your eyes and detect the light rays streaming through your bedroom window (transmission), illuminating your socks on the floor (scattering). You put on your glasses (refraction) to detect the state of your image in the mirror (reflection). If you are an ALS scientist, perhaps you go to work and shine some x-ray light on a crystal to detect the arrangement of the atoms in the crystal (diffraction). Now, thanks to Turner et al., you can also shine some x-ray light on a magnetic sample to detect the arrangement of its electron spins through a method known as lensless imaging. This last example is an equally valid way to "see," but instead of using windows, lenses, or mirrors to manipulate light and construct an image, mathematical formulas are used to describe the effects that particles and fields in the sample have on the light. These formulas have always contained terms that relate to the electron spin of magnetic atoms, but they were previously ignored. Using the full formula allows for the determination of not only crystal structure, but magnetic spin distribution and orientation as well, with a spatial resolution limited only by the wavelength 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 changes, offering the potential for imaging in unprecedented detail the structure and motion of boundaries between regions with different magnetic orientation.

16

Lensless Imaging of Magnetic Nanostructures  

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

Lensless Imaging of Magnetic Nanostructures Print 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 for the first time to nanometer-scale magnetic structures in an alloy. Many Ways To See You open your eyes and detect the light rays streaming through your bedroom window (transmission), illuminating your socks on the floor (scattering). You put on your glasses (refraction) to detect the state of your image in the mirror (reflection). If you are an ALS scientist, perhaps you go to work and shine some x-ray light on a crystal to detect the arrangement of the atoms in the crystal (diffraction). Now, thanks to Turner et al., you can also shine some x-ray light on a magnetic sample to detect the arrangement of its electron spins through a method known as lensless imaging. This last example is an equally valid way to "see," but instead of using windows, lenses, or mirrors to manipulate light and construct an image, mathematical formulas are used to describe the effects that particles and fields in the sample have on the light. These formulas have always contained terms that relate to the electron spin of magnetic atoms, but they were previously ignored. Using the full formula allows for the determination of not only crystal structure, but magnetic spin distribution and orientation as well, with a spatial resolution limited only by the wavelength 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 changes, offering the potential for imaging in unprecedented detail the structure and motion of boundaries between regions with different magnetic orientation.

17

Lensless Imaging of Magnetic Nanostructures  

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

Lensless Imaging of Magnetic Nanostructures Print 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 for the first time to nanometer-scale magnetic structures in an alloy. Many Ways To See You open your eyes and detect the light rays streaming through your bedroom window (transmission), illuminating your socks on the floor (scattering). You put on your glasses (refraction) to detect the state of your image in the mirror (reflection). If you are an ALS scientist, perhaps you go to work and shine some x-ray light on a crystal to detect the arrangement of the atoms in the crystal (diffraction). Now, thanks to Turner et al., you can also shine some x-ray light on a magnetic sample to detect the arrangement of its electron spins through a method known as lensless imaging. This last example is an equally valid way to "see," but instead of using windows, lenses, or mirrors to manipulate light and construct an image, mathematical formulas are used to describe the effects that particles and fields in the sample have on the light. These formulas have always contained terms that relate to the electron spin of magnetic atoms, but they were previously ignored. Using the full formula allows for the determination of not only crystal structure, but magnetic spin distribution and orientation as well, with a spatial resolution limited only by the wavelength 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 changes, offering the potential for imaging in unprecedented detail the structure and motion of boundaries between regions with different magnetic orientation.

18

Lensless Imaging of Magnetic Nanostructures  

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

Lensless Imaging of Magnetic Nanostructures Print 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 for the first time to nanometer-scale magnetic structures in an alloy. Many Ways To See You open your eyes and detect the light rays streaming through your bedroom window (transmission), illuminating your socks on the floor (scattering). You put on your glasses (refraction) to detect the state of your image in the mirror (reflection). If you are an ALS scientist, perhaps you go to work and shine some x-ray light on a crystal to detect the arrangement of the atoms in the crystal (diffraction). Now, thanks to Turner et al., you can also shine some x-ray light on a magnetic sample to detect the arrangement of its electron spins through a method known as lensless imaging. This last example is an equally valid way to "see," but instead of using windows, lenses, or mirrors to manipulate light and construct an image, mathematical formulas are used to describe the effects that particles and fields in the sample have on the light. These formulas have always contained terms that relate to the electron spin of magnetic atoms, but they were previously ignored. Using the full formula allows for the determination of not only crystal structure, but magnetic spin distribution and orientation as well, with a spatial resolution limited only by the wavelength 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 changes, offering the potential for imaging in unprecedented detail the structure and motion of boundaries between regions with different magnetic orientation.

19

Lensless Imaging of Magnetic Nanostructures  

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

Lensless Imaging of Magnetic Nanostructures Print 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 for the first time to nanometer-scale magnetic structures in an alloy. Many Ways To See You open your eyes and detect the light rays streaming through your bedroom window (transmission), illuminating your socks on the floor (scattering). You put on your glasses (refraction) to detect the state of your image in the mirror (reflection). If you are an ALS scientist, perhaps you go to work and shine some x-ray light on a crystal to detect the arrangement of the atoms in the crystal (diffraction). Now, thanks to Turner et al., you can also shine some x-ray light on a magnetic sample to detect the arrangement of its electron spins through a method known as lensless imaging. This last example is an equally valid way to "see," but instead of using windows, lenses, or mirrors to manipulate light and construct an image, mathematical formulas are used to describe the effects that particles and fields in the sample have on the light. These formulas have always contained terms that relate to the electron spin of magnetic atoms, but they were previously ignored. Using the full formula allows for the determination of not only crystal structure, but magnetic spin distribution and orientation as well, with a spatial resolution limited only by the wavelength 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 changes, offering the potential for imaging in unprecedented detail the structure and motion of boundaries between regions with different magnetic orientation.

20

Magnetic imaging of shipwrecks  

E-Print Network (OSTI)

The ferromagnetic material in a shipwreck on the seabed causes a modification to the earth's magnetic field which can be measured at the surface. Proton magnetometer measurements at the surface are used to locate wrecks. Here I discuss how to interpret such data to explore the shape and orientation of the shipwreck on the seabed. I give details of how to model shipwrecks and deduce the magnetic signal that results. I also discuss how to analyse data in a more general way. As examples, I present and analyse data on the shipwrecks of YSTROOM and BOUBOULINA (ex COLONEL LAMB).

Michael, C

2011-01-01T23:59:59.000Z

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


21

Imaging agents for in vivo magnetic resonance and scintigraphic imaging  

DOE Patents (OSTI)

Methods are provided for in vivo magnetic resonance imaging and/or scintigraphic imaging of a subject using chelated transition metal and lanthanide metal complexes. Novel ligands for these complexes are provided.

Engelstad, Barry L. (Orinda, CA); Raymond, Kenneth N. (Berkeley, CA); Huberty, John P. (Corte Madera, CA); White, David L. (Oakland, CA)

1991-01-01T23:59:59.000Z

22

Imaging agents for in vivo magnetic resonance and scintigraphic imaging  

DOE Patents (OSTI)

Methods are provided for in vivo magnetic resonance imaging and/or scintigraphic imaging of a subject using chelated transition metal and lanthanide metal complexes. Novel ligands for these complexes are provided. No Drawings

Engelstad, B.L.; Raymond, K.N.; Huberty, J.P.; White, D.L.

1991-04-23T23:59:59.000Z

23

Direct Imaging of Asymmetric Magnetization Reversal  

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

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

24

Magnetic resonance imaging in Mexico  

Science Conference Proceedings (OSTI)

MR imaging has experienced an important growth worldwide and in particular in the USA and Japan. This imaging technique has also shown an important rise in the number of MR imagers in Mexico. However

A. O. Rodriguez; R. Rojas; F. A. Barrios

2001-01-01T23:59:59.000Z

25

Filamentation instability of current-driven dust ion-acoustic waves in a collisional dusty plasma  

Science Conference Proceedings (OSTI)

A theoretical investigation has been made of the dust ion-acoustic filamentation instability in an unmagnetized current-driven dusty plasma by using the Lorentz transformation formulas. The effect of collision between the charged particles with neutrals and their thermal motion on this instability is considered. Developing the filamentation instability of the current-driven dust ion-acoustic wave allows us to determine the period and the establishment time of the filamentation structure and threshold for instability development.

Niknam, A. R. [Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Tehran 19839-63113 (Iran, Islamic Republic of); Haghtalab, T.; Khorashadizadeh, S. M. [Physics Department, Birjand University, Birjand 97179-63384 (Iran, Islamic Republic of)

2011-11-15T23:59:59.000Z

26

Application of Parallel Imaging to Murine Magnetic Resonance Imaging  

E-Print Network (OSTI)

The use of parallel imaging techniques for image acceleration is now common in clinical magnetic resonance imaging (MRI). There has been limited work, however, in translating the parallel imaging techniques to routine animal imaging. This dissertation describes foundational level work to enable parallel imaging of mice on a 4.7 Tesla/40 cm bore research scanner. Reducing the size of the hardware setup associated with typical parallel imaging was an integral part of achieving the work, as animal scanners are typically small-bore systems. To that end, an array element design is described that inherently decouples from a homogenous transmit field, potentially allowing for elimination of typically necessary active detuning switches. The unbalanced feed of this "dual-plane pair" element also eliminates the need for baluns in this case. The use of the element design in a 10-channel adjustable array coil for mouse imaging is presented, styled as a human cardiac top-bottom half-rack design. The design and construction of the homogenous transmit birdcage coil used is also described, one of the necessary components to eliminating the active detuning networks on the array elements. In addition, the design of a compact, modular multi-channel isolation preamplifier board is described, removing the preamplifiers from the elements and saving space in the bore. Several additions/improvements to existing laboratory infrastructure needed for parallel imaging of live mice are also described, including readying an animal preparation area and developing the ability to maintain isoflurane anesthesia delivery during scanning. In addition, the ability to trigger the MRI scanner to the ECG and respiratory signals from the mouse in order to achieve images free from physiological motion artifacts is described. The imaging results from the compact 10-channel mouse array coils are presented, and the challenges associated with the work are described, including difficulty achieving sample-loss dominance and signal-to-noise ratio (SNR) limitations. In conclusion, in vivo imaging of mice with cardiac and respiratory gating has been demonstrated. Compact array coils tailored for mice have been studied and potential future work and design improvements for our lab in this area are discussed.

Chang, Chieh-Wei 1980-

2012-12-01T23:59:59.000Z

27

Dust-acoustic filamentation of a current-driven dusty plasma  

Science Conference Proceedings (OSTI)

The thermal motion effect of charged particles in the filamentation of a current-driven dusty plasma in the dust-acoustic frequency region is investigated by using the Lorentz transformed conductivity of the dusty plasma components and the total dielectric permittivity tensor of the dusty plasma in the laboratory frame. Obtaining the dispersion relation for dust-acoustic waves and considering the filamentation instability, the establishment time of the filamentation structure and the instability development threshold are derived. Moreover, it is shown that the current layer divides into separate current filaments.

Khorashadizadeh, S. M.; Haghtalab, T. [Physics Department, Birjand University, Birjand, 97179-63384 (Iran, Islamic Republic of); Niknam, A. R. [Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Tehran, 19839-63113 (Iran, Islamic Republic of)

2011-06-15T23:59:59.000Z

28

Quantitative imaging of stray fields and magnetization distributions in hard magnetic element arrays  

E-Print Network (OSTI)

Quantitative imaging of stray fields and magnetization distributions in hard magnetic element with inverse magnetostatic methods. The method is applied to hard magnetic FePt and PrCo5 films which exhibit of thin hard magnetic elements. We show that by application of the MOIF technique and inverse

Johansen, Tom Henning

29

Magnetic charge crystals imaged in artificial spin ice  

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

Magnetic charge crystals imaged in artificial spin ice Magnetic charge crystals imaged in artificial spin ice Magnetic charge crystals imaged in artificial spin ice Potential data storage and computational advances could follow August 27, 2013 Potential data storage and computational advances could follow A 3-D depiction of the honeycomb artificial spin ice topography after the annealing and cooling protocols. The light and dark colors represent the north and south magnetic poles of the islands. Image by Ian Gilbert, U. of I. Department of Physics and Frederick Seitz Materials Research Laboratory Contact Nancy Ambrosiano Communications Office (505) 667-0471 Email Siv Schwink U. Illinois (217) 300-2201 Email "The emergence of magnetic monopoles in spin ice systems is a particular case of what physicists call fractionalization, or deconfinement of

30

Final Technical Report of DE-FG02-06ER54789 Current-Driven Filament Instabilities in Relativistic Plasmas  

SciTech Connect

This grant has supported a study of some fundamental problems in current- and flowdriven instabilities in plasmas and their applications in inertial confinement fusion (ICF) and astrophysics. It addressed current-driven instabilities and their roles in fast ignition, and flow-driven instabilities and their applications in astrophysics.

Ren, Chuang

2013-02-13T23:59:59.000Z

31

Method for nuclear magnetic resonance imaging  

DOE Patents (OSTI)

A method for in vivo NMR imaging of the blood vessels and organs of a patient characterized by using a dark dye-like imaging substance consisting essentially of a stable, high-purity concentration of D/sub 2/O in a solution with water.

Kehayias, J.J.; Joel, D.D.; Adams, W.H.; Stein, H.L.

1988-05-26T23:59:59.000Z

32

Ultra-low field nuclear magnetic resonance and magnetic resonance imaging to discriminate and identify materials  

DOE Patents (OSTI)

An ultra-low magnetic field NMR system can non-invasively examine containers. Database matching techniques can then identify hazardous materials within the containers. Ultra-low field NMR systems are ideal for this purpose because they do not require large powerful magnets and because they can examine materials enclosed in conductive shells such as lead shells. The NMR examination technique can be combined with ultra-low field NMR imaging, where an NMR image is obtained and analyzed to identify target volumes. Spatial sensitivity encoding can also be used to identify target volumes. After the target volumes are identified the NMR measurement technique can be used to identify their contents.

Kraus, Robert H. (Los Alamos, NM); Matlashov, Andrei N. (Los Alamos, NM); Espy, Michelle A. (Los Alamos, NM); Volegov, Petr L. (Los Alamos, NM)

2010-03-30T23:59:59.000Z

33

Inhibition of the current-driven ion wave instability by electron trapping in the FM-1 spherator  

SciTech Connect

An experimental analysis is made of the scattering of microwaves by the density fluctuations due to the current-driven ion wave instability in a toroidal plasma confinement device, the FM-1 spherator. It is found that the instability exists in the collisional regime and it is inhibited (i.e., quenched by two orders in magnitude) in the trapped-electron (i.e., banana) regime. The inhibition occurs when the electron collision frequency is about equal to the electron bounce frequency between mirror trapping. (auth)

Arunasalam, V.; Okabayaski, M.; Hawryluk, R.J.; Suckewer, S.

1975-10-01T23:59:59.000Z

34

Soft x-ray microscopy - a powerful analytical tool to image magnetism down to fundamental length and times scales  

E-Print Network (OSTI)

image magnetism down to fundamental length and time scalesmicroscopies have to tackle fundamental magnetic length andregard to addressing fundamental magnetic length and time

Fischer, Peter

2008-01-01T23:59:59.000Z

35

Superconducting matrix fault current limiter with current-driven trigger mechanism  

DOE Patents (OSTI)

A modular and scalable Matrix-type Fault Current Limiter (MFCL) that functions as a "variable impedance" device in an electric power network, using components made of superconducting and non-superconducting electrically conductive materials. An inductor is connected in series with the trigger superconductor in the trigger matrix and physically surrounds the superconductor. The current surge during a fault will generate a trigger magnetic field in the series inductor to cause fast and uniform quenching of the trigger superconductor to significantly reduce burnout risk due to superconductor material non-uniformity.

Yuan, Xing (Albany, NY)

2008-04-15T23:59:59.000Z

36

Current driven instabilities of the kinetic shear Alfven wave: application to reversed field pinches and spheromaks  

DOE Green Energy (OSTI)

The kinetic Alfven wave is studied in a cylindrical force-free plasma with self-consistent magnetic fields. This equilibrium represents a reversed field pinch or a spheromak. The stability of the wave is found to depend on the ratio of the electron drift velocity to the Alfven velocity. This ratio varies inversely with the square root of the plasma line density. The critical line density using the Spitzer-Harm electron distribution function is found for reversed field pinches with deuterium plasmas to be approximately 2 x 10/sup 18/ m/sup -1/ and is 5 x 10/sup 17/ m/sup -1/ in spheromaks with hydrogen plasmas. The critical line density is in reasonable agreement with experimental data for reversed field pinches.

Meyerhofer, D.D.; Perkins, F.W.

1984-04-01T23:59:59.000Z

37

Linear and nonlinear dynamics of current-driven waves in dusty plasmas  

SciTech Connect

The linear and nonlinear dynamics of a recently proposed plasma mode of dusty plasma is studied using kappa distribution for electrons. This electrostatic wave can propagate in the plasma due to the sheared flow of electrons and ions parallel to the external magnetic field in the presence of stationary dust. The coupling of this wave with the usual drift wave and ion acoustic wave is investigated. D'Angelo's mode is also modified in the presence of superthermal electrons. In the nonlinear regime, the wave can give rise to dipolar vortex structures if the shear in flow is weaker and tripolar vortices if the flow has steeper gradient. The results have been applied to Saturn's magnetosphere corresponding to negatively charged dust grains. But the theoretical model is applicable for positively charged dust as well. This work will be useful for future observations and studies of dusty environments of planets and comets.

Ahmad, Ali [National Centre for Physics (NCP), Shahdara Valley Road, 44000 Islamabad (Pakistan); Department of Physics, COMSATS Institute of Information Technology (CIIT), Islamabad (Pakistan); Theoretical Plasma Physics Division, PINSTECH, P. O. Nilore, Islamabad (Pakistan); Ali Shan, S.; Haque, Q. [National Centre for Physics (NCP), Shahdara Valley Road, 44000 Islamabad (Pakistan); Theoretical Plasma Physics Division, PINSTECH, P. O. Nilore, Islamabad (Pakistan); Saleem, H. [National Centre for Physics (NCP), Shahdara Valley Road, 44000 Islamabad (Pakistan); Department of Physics, COMSATS Institute of Information Technology (CIIT), Islamabad (Pakistan)

2012-09-15T23:59:59.000Z

38

Microfluidically Cryo-Cooled Planar Coils for Magnetic Resonance Imaging  

E-Print Network (OSTI)

High signal-to-noise ratio (SNR) is typically required for higher resolution and faster speed in magnetic resonance imaging (MRI). Planar microcoils as receiver probes in MRI systems offer the potential to be configured into array elements for fast imaging as well as to enable the imaging of extremely small objects. Microcoils, however, are thermal noise dominant and suffer limited SNR. Cryo-cooling for the microcoils can reduce the thermal noise, however conventional cryostats are not optimum for the microcoils because they typically use a thick vacuum gap to keep samples to be imaged to near room temperature during cryo-cooling. This vacuum gap is typically larger than the most sensitive region of the microcoils that defines the imaging depth, which is approximately the same as the diameters of the microcoils. Here microfluidic technology is utilized to locally cryo-cool the microcoils and minimize the thermal isolation gap so that the imaging surface is within the imaging depth of the microcoils. The first system consists of a planar microcoil with microfluidically cryo-cooling channels, a thin N2 gap and an imaging. The microcoil was locally cryo-cooled while maintaining the sample above 8C. MR images using a 4.7 Tesla MRI system shows an average SNR enhancement of 1.47 fold. Second, the system has been further developed into a cryo-cooled microcoil system with inductive coupling to cryo-cool both the microcoil and the on-chip microfabricated resonating capacitor to further improve the Q improvement. Here inductive coupling was used to eliminate the physical connection between the microcoil and the tuning network so that a single cryocooling microfluidic channel could enclose both the microcoil and the capacitor with minimum loss in cooling capacity. Q improvement was 2.6 fold compared to a conventional microcoil with high-Q varactors and transmission line connection. Microfluidically tunable capacitors with the 653% tunability and Q of 1.3 fold higher compared to a conventional varactor have been developed and demonstrated as matching/tuning networks as a proof of concept. These developed microfluidically cryo-cooling system and tunable capacitors for improving SNR will potentially allow MR microcoils to have high-resolution images over small samples.

Koo, Chiwan

2013-08-01T23:59:59.000Z

39

Magnetic Resonance Imaging at Princeton, UofV, and UNH | U.S...  

Office of Science (SC) Website

Magnetic Resonance Imaging at Princeton, UofV, and UNH Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff...

40

THERMAL IMAGING OF ACTIVE MAGNETIC REGERNERATOR MCE MATERIALS DURING OPERATION  

SciTech Connect

An active magnetic regenerator (AMR) prototype was constructed that incorporates a Gd sheet into the regenerator wall to enable visualization of the system s thermal transients. In this experiment, the thermal conditions inside the AMR are observed under a variety of operating conditions. An infrared (IR) camera is employed to visualize the thermal transients within the AMR. The IR camera is used to visually and quantitatively evaluate the temperature difference and thus giving means to calculate the performance of the system under the various operating conditions. Thermal imaging results are presented for two differing experimental test runs. Real time imaging of the thermal state of the AMR has been conducted while operating the system over a range of conditions. A 1 Tesla twin-coil electromagnet (situated on a C frame base) is used for this experiment such that all components are stationary during testing. A modular, linear reciprocating system has been realized in which the effects of regenerator porosity and utilization factor can be investigated. To evaluate the performance variation in porosity and utilization factor the AMR housing was constructed such that the plate spacing of the Gd sheets may be varied. Each Gd sheet has dimensions of 38 mm wide and 66 mm long with a thickness of 1 mm and the regenerator can hold a maximum of 29 plates with a spacing of 0.25 mm. Quantitative and thermal imaging results are presented for several regenerator configurations.

Shassere, Benjamin [ORNL; West, David L [ORNL; Abdelaziz, Omar [ORNL; Evans III, Boyd Mccutchen [ORNL

2012-01-01T23:59:59.000Z

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


41

Magnetic soft x-ray microscopy-imaging fast spin dynamics inmagnetic nanostructures  

SciTech Connect

Magnetic soft X-ray microscopy combines 15nm spatial resolution with 70ps time resolution and elemental sensitivity. Fresnel zone plates are used as X-ray optics and X-ray magnetic circular dichroism serves as magnetic contrast mechanism. Thus scientifically interesting and technologically relevant low dimensional nanomagnetic systems can be imaged at fundamental length and ultrafast time scales in a unique way. Studies include magnetization reversal in magnetic multilayers, nanopatterned systems, vortex dynamics in nanoelements and spin current induced phenomena.

Fischer, Peter; Kim, Dong-Hyun; Mesler, Brooke L.; Chao, Weilun; Sakdinawat, Anne E.; Anderson, Erik H.

2007-06-01T23:59:59.000Z

42

Segmentation of female pelvic organs in axial magnetic resonance images using coupled geometric deformable models  

Science Conference Proceedings (OSTI)

The segmentation of pelvic structures in magnetic resonance (MR) images of the female pelvic cavity is a challenging task. This paper proposes the use of three novel geometric deformable models to segment the bladder, vagina and rectum in axial MR images. ... Keywords: Bladder, Image segmentation, Imaging appearance, Level set, Prior shape knowledge, Rectum, Vagina

Zhen Ma; Renato M. Natal Jorge; Teresa Mascarenhas; JoO Manuel R. S. Tavares

2013-05-01T23:59:59.000Z

43

Recovery of 3D Solar Magnetic Field Model Parameter Using Image Structure Matching  

Science Conference Proceedings (OSTI)

An approach to recover a 3D solar magnetic field model parameter using intensity images of the Sun's corona is introduced. The approach is a quantitative approach in which the 3D model parameter is determined via an image structure matching scheme. The ... Keywords: 3D Parameter Recovery, Image-based Modeling, Structure Matching

Jong Kwan Lee; G. Allen Gary

2009-05-01T23:59:59.000Z

44

Spectroscopic imaging through magnetic resonance for brain tumour diagnostics: Recent achievements, dilemmas and potential solutions via advances in signal processing  

Science Conference Proceedings (OSTI)

In the very recent period Magnetic Resonance Spectroscopy (MRS) and Spectroscopic Imaging (MRSI) have become key diagnostic modalities for neuro-oncology. MRS and MRSI are now applied extensively for initial detection of brain tumours, for histopathologic ... Keywords: biomedical imaging, brain tumours, magnetic resonance spectroscopic imaging, magnetic resonance spectroscopy, metastatic disease

Karen Belki?; Devad Belki?

2004-04-01T23:59:59.000Z

45

Magnetic resonance imaging of solvent transport in polymer networks  

SciTech Connect

The spectroscopic technique of magnetic resonance imaging (MRI) has recently provided a new window into transport of solvents in polymer networks. Diffusion of solvent as a rate-controlling phenomenon is paramount to understanding transport in many important industrial and biological processes, such as upgrading fossil fuels, film casting and coating, development of photoresists, design of drug-delivery systems, development of solvent resistant polymers, etc. By MRI mapping the migration of solvent molecules through various polymer specimens, researchers Robert Botto and George Cody of Argonne National Laboratory, with support from the Division of Chemical Sciences at DOE, were able to characterize and distinguish between different modes of transport behavior associated with fundamentally different types of polymer systems. The method was applied to rubbers, glassy polymers, and coals. In polymers shown to undergo a glass transition from a rigid to rubbery state, a sharply defined solvent front was observed that propagated through specimens in the manner of a constant velocity shock wave. This behavior was contrasted with a smooth solvent concentration gradient found in polymer systems where no glass transition was observed. The results of this analysis have formed the basis of a new model of anomalous transport in polymeric solids and are helping to ascertain fundamental information on the molecular architectures of these materials.

Botto, R.E.; Cody, G.D.

1995-02-01T23:59:59.000Z

46

Power Quality Investigation at a Midwest Hospital: Magnetic Resonance Imaging System  

Science Conference Proceedings (OSTI)

Recently, a Midwest hospital contacted its electric utility about malfunctions involving imaging systems including magnetic resonance imaging (MRI) and computed tomography (CT). The MRI system was the primary concern for the hospital. The MRI system was manufactured by a leading imaging system manufacturer and the CT system was manufactured by another leading imaging system manufacturer. To begin investigating the problem, the hospital requested that power-line monitoring be conducted at the facility. Th...

2007-07-26T23:59:59.000Z

47

HST.583 Functional Magnetic Resonance Imaging: Data Acquisition and Analysis, Fall 2006  

E-Print Network (OSTI)

This team taught, multidisciplinary course covers the fundamentals of magnetic resonance imaging relevant to the conduct and interpretation of human brain mapping studies. The challenges inherent in advancing our knowledge ...

Gollub, Randy L.

48

Multimodal neuroimaging with simultaneous electroencephalogram and high-field functional magnetic resonance imaging  

E-Print Network (OSTI)

Simultaneous recording of electroencephalogram (EEG) and functional magnetic resonance imaging (tMRI) is an important emerging tool in functional neuroimaging with the potential to reveal new mechanisms for brain function ...

Purdon, Patrick L. (Patrick Lee), 1974-

2005-01-01T23:59:59.000Z

49

Imaging nanoscale magnetic structures with polarized soft x-ray photons  

SciTech Connect

Imaging nanoscale magnetic structures and their fast dynamics is scientifically interesting and technologically of highest relevance. The combination of circularly polarized soft X-ray photons which provide a strong X-ray magnetic circular dichroism effect at characteristic X-ray absorption edges, with a high resolution soft X-ray microscope utilizing Fresnel zone plate optics allows to study in a unique way the stochastical behavior in the magnetization reversal process of thin films and the ultrafast dynamics of magnetic vortices and domain walls in confined ferromagnetic structures. Future sources of fsec short and high intense soft X-ray photon pulses hold the promise of magnetic imaging down to fundamental magnetic length and time scales.

Fischer, P.; Im, M.-Y.

2010-01-18T23:59:59.000Z

50

Automatic segmentation of non-enhancing brain tumors in magnetic resonance images  

Science Conference Proceedings (OSTI)

Tumor segmentation from magnetic resonance (MR) images may aid in tumor treatment by tracking the progress of tumor growth and/or shrinkage. In this paper we present the first automatic segmentation method which separates non-enhancing brain tumors from ... Keywords: Automatic tissue classification, Fuzzy clustering, Image processing, MRI, Non-enhancing brain tumors

Lynn M Fletcher-Heath; Lawrence O Hall; Dmitry B Goldgof; F.Reed Murtagh

2001-01-01T23:59:59.000Z

51

Cranial anatomy and detection of ischemic stroke in the cat by nuclear magnetic resonance imaging  

SciTech Connect

Proton nuclear magnetic resonance (NMR) images of cat heads were obtained using a small, experimental imaging system. As a prelude to the study of experimental ischemic brain infarction, the normal cat head was imaged for identification of anatomical features. Images of one cat which had undergone ligation of the middle cerebral artery three weeks previously showed brain changes associated with chronic ischemic stroke and compared favorably with findings on computed tomography (CT). The NMR images have millimetric spatial resolution. NMR parameters inherent in the tissues provide intensity variations and are sufficiently sensitive to yield contrast resolution surpassing that of CT.

Buonanno, F.S.; Pykett, I.L.; Kistler, J.P.; Vielma, J.; Brady, T.J.; Hinshaw, W.S.; Goldman, M.R.; Newhouse, J.H.; Pohost, G.M.

1982-04-01T23:59:59.000Z

52

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

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

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

53

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

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

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

54

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

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

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

55

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

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

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

56

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

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

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

57

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

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

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

58

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

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

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

59

Magnetic Resonance Imaging at Princeton, UofV, and UNH | U.S. DOE Office of  

Office of Science (SC) Website

Magnetic Resonance Imaging at Magnetic Resonance Imaging at Princeton, UofV, and UNH Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives Magnetic Resonance Imaging at Princeton, UofV, and UNH Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: MRI for hyperpolarized gases Developed at: Princeton, University of Virginia, University of New Hampshire

60

Magneto-Optical Images from the Superconductivity & Magnetism Low-temperature Laboratory  

DOE Data Explorer (OSTI)

This is a small, online collection of video supplements to published papers, images, Flash movies, etc. Activities of the Superconductivity and Magnetism Low-Temperature Lab are focused on the experimental studies of superconductivity, magnetism and their coexistence in novel materials at low temperatures. In addition to the magneto-optical gallery, see the video supplements at http://www.cmpgroup.ameslab.gov/supermaglab/video/index.html

Condensed Matter Physics Group (Iowa State University and Ames Laboratory)

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


61

Scientific Image Gallery from the Applied Superconductivity Center at the National High Magnetic Field Laboratory  

DOE Data Explorer (OSTI)

The Applied Superconductivity Center (ASC) is nested with the National High Magnetic Field Laboratory. Originally located at the University of Wisconsin, ASC transferred to NHMFL or Magnet Lab in 2003. ASC investigates both low and high-temperature materials. Focus areas include grain boundaries; coated conductors, BSCCO, and a new superconductor known as MgB2. The ASC Image Gallery provides graphs with text descriptions and single images with captions. The single images are organized into collections under scientific titles, such as MgB2 mentioned above. Click on the Videos link to see two 3D videos and be sure to check out the link to image collections at other organizations performing superconductivity research.

62

Fast Magnetic Resonance Imaging via Adaptive Broadband Encoding of the MR Signal Content  

E-Print Network (OSTI)

signal is radiated from the sample and decays over time both via the return of the sample's magnetization decays after sample excitation. Relaxation times of the order of 1sec in human tissue make the process studies where a continu- ous series of images is required, for example in contrast bolus tracking

Edelman, Alan

63

Detecting tumor responses to treatment using hyperpolarized 13C magnetic resonance spectroscopic imaging  

E-Print Network (OSTI)

- labeled bicarbonate. Nature 2008, 453:940-943. doi:10.1038/nrc2289 Cite this article as: Brindle: Detecting tumor responses to treatment using hyperpolarized 13C magnetic resonance spectroscopic imaging. BMC Proceedings 2010 4(Suppl 2):O24. Correspondence...

2010-09-24T23:59:59.000Z

64

Elemental and magnetic sensitive imaging using x-ray excited luminescence microscopy  

Science Conference Proceedings (OSTI)

We demonstrate the potential of x-ray excited luminescence microscopy for full-field elemental and magnetic sensitive imaging using a commercially available optical microscope, mounted on preexisting synchrotron radiation (SR) beamline end stations. The principal components of the instrument will be described. Bench top measurements indicate that a resolution of 1 {mu}m or better is possible; this value was degraded in practice due to vibrations and/or drift in the end station and associated manipulator. X-ray energy dependent measurements performed on model solar cell materials and lithographically patterned magnetic thin film structures reveal clear elemental and magnetic signatures. The merits of the apparatus will be discussed in terms of conventional SR imaging techniques.

Rosenberg, R. A.; Zohar, S.; Keavney, D. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Divan, R.; Rosenmann, D. [Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Mascarenhas, A.; Steiner, M. A. [National Renewable Energy Lab, Golden, Colorado 80401 (United States)

2012-07-15T23:59:59.000Z

65

Direct imaging of neural currents using ultra-low field magnetic resonance techniques  

DOE Patents (OSTI)

Using resonant interactions to directly and tomographically image neural activity in the human brain using magnetic resonance imaging (MRI) techniques at ultra-low field (ULF), the present inventors have established an approach that is sensitive to magnetic field distributions local to the spin population in cortex at the Larmor frequency of the measurement field. Because the Larmor frequency can be readily manipulated (through varying B.sub.m), one can also envision using ULF-DNI to image the frequency distribution of the local fields in cortex. Such information, taken together with simultaneous acquisition of MEG and ULF-NMR signals, enables non-invasive exploration of the correlation between local fields induced by neural activity in cortex and more `distant` measures of brain activity such as MEG and EEG.

Volegov, Petr L. (Los Alamos, NM); Matlashov, Andrei N. (Los Alamos, NM); Mosher, John C. (Los Alamos, NM); Espy, Michelle A. (Los Alamos, NM); Kraus, Jr., Robert H. (Los Alamos, NM)

2009-08-11T23:59:59.000Z

66

Remote Energetic Neutral Atom Imaging of Electric Potential Over a Lunar Magnetic Anomaly  

E-Print Network (OSTI)

The formation of electric potential over lunar magnetized regions is essential for understanding fundamental lunar science, for understanding the lunar environment, and for planning human exploration on the Moon. A large positive electric potential was predicted and detected from single point measurements. Here, we demonstrate a remote imaging technique of electric potential mapping at the lunar surface, making use of a new concept involving hydrogen neutral atoms derived from solar wind. We apply the technique to a lunar magnetized region using an existing dataset of the neutral atom energy spectrometer SARA/CENA on Chandrayaan-1. Electrostatic potential larger than +135 V inside the Gerasimovic anomaly is confirmed. This structure is found spreading all over the magnetized region. The widely spread electric potential can influence the local plasma and dust environment near the magnetic anomaly.

Futaana, Y; Wieser, M; Lue, C; Wurz, P; Vorburger, A; Bhardwaj, A; Asamura, K; 10.1002/grl.50135

2013-01-01T23:59:59.000Z

67

Three dimensional nuclear magnetic resonance spectroscopic imaging of sodium ions using stochastic excitation and oscillating gradients  

SciTech Connect

Nuclear magnetic resonance (NMR) spectroscopic imaging of {sup 23}Na holds promise as a non-invasive method of mapping Na{sup +} distributions, and for differentiating pools of Na{sup +} ions in biological tissues. However, due to NMR relaxation properties of {sup 23}Na in vivo, a large fraction of Na{sup +} is not visible with conventional NMR imaging methods. An alternate imaging method, based on stochastic excitation and oscillating gradients, has been developed which is well adapted to measuring nuclei with short T{sub 2}. Contemporary NMR imaging techniques have dead times of up to several hundred microseconds between excitation and sampling, comparable to the shortest in vivo {sup 23}Na T{sub 2} values, causing significant signal loss. An imaging strategy based on stochastic excitation has been developed which greatly reduces experiment dead time by reducing peak radiofrequency (RF) excitation power and using a novel RF circuit to speed probe recovery. Continuously oscillating gradients are used to eliminate transient eddy currents. Stochastic {sup 1}H and {sup 23}Na spectroscopic imaging experiments have been performed on a small animal system with dead times as low as 25{mu}s, permitting spectroscopic imaging with 100% visibility in vivo. As an additional benefit, the encoding time for a 32x32x32 spectroscopic image is under 30 seconds. The development and analysis of stochastic NMR imaging has been hampered by limitations of the existing phase demodulation reconstruction technique. Three dimensional imaging was impractical due to reconstruction time, and design and analysis of proposed experiments was limited by the mathematical intractability of the reconstruction method. A new reconstruction method for stochastic NMR based on Fourier interpolation has been formulated combining the advantage of a several hundredfold reduction in reconstruction time with a straightforward mathematical form.

Frederick, B.deB. [California Univ., Berkeley, CA (United States)]|[Lawrence Berkeley Lab., CA (United States)

1994-12-01T23:59:59.000Z

68

Minute Effects of Sex on the Aging Brain: A Multisample Magnetic Resonance Imaging Study of Healthy Aging and Alzheimer's Disease  

E-Print Network (OSTI)

Age is associated with substantial macrostructural brain changes. While some recent magnetic resonance imaging studies have reported larger age effects in men than women, others find no sex differences. As brain morphometry ...

Fjell, Anders M.

69

Imaging magnetic sources in the presence of superconducting surfaces : model&experiment  

DOE Green Energy (OSTI)

The forward physics model describing the effect of a superconducting surface on the magnetic field distribution resulting from specific magnetic sources has numerous applications ranging from basic physics experiments to large superconducting magnets used in energy storage and magnetic resonance imaging. In this paper, we describe the novel application of a superconducting imaging surface (SIS) to enhance the performance of systems designed to directly observe and localize human brain function. Magnetoencephalography (MEG) measures the weak magnetic fields emanating from the brain as a direct consequence of the neuronal currents resulting from brain function[1]. The extraordinarily weak magnetic fields are measured by an array of SQUID (Superconducting QUantum Interference Device) sensors. The position and vector characteristics of these neuronal sources can be estimated from the inverse solution of the field distribution at the surface of the head. In addition, MEG temporal resolution is unsurpassed by any other method currently used for brain imaging. Although MEG source reconstruction is limited by solutions of the electromagnetic inverse problem, constraints used for source localization produce reliable results. A novel MEG system incorporating a SIS has been designed and built at Los Alamos with the goal of dramatically improving source localization accuracy while mitigating limitations of current systems (e.g. low signal-to-noise, cost, bulk). We incorporate shielding and source field measurement into an integrated design and combine the latest SQUID and data acquisition technology. The Los Alamos MEG system is based on the principal that fields from nearby sources measured by a SQUID sensor array while the SIS simultaneously shields the sensor array from distant noise fields. In general, Meissner currents flow in the surface of superconductors, preventing any significant penetration of magnetic fields. A hemispherical SIS with a brim, or helmet, surrounds the SQUID sensor array largely sheilding the SQUID sensors from sources outside the helmet. We present the general derivation of the forward model used to describe the effect of a SIS on source fields. Experimental data for the SIS-MEG system are compared with computed field distributions for a comprehensive set of sources.

Matlachov, A. N. (Andrei N.); Espy, M. A. (Michelle A.); Volegov, P. (Petr); Flynn, E. R. (Edward. R.); Maharajh, K. (Keeran); Kraus, Robert H., Jr.

2001-01-01T23:59:59.000Z

70

Development of Nuclear Magnetic Resonance Imaging/spectroscopy for improved petroleum recovery. Final report  

SciTech Connect

The overall objectives of this program are to develop and apply Nuclear Magnetic Resonance Imaging (NMRI) and CT X-Ray Scanning methods for determining rock, fluid, and petrophysical properties and for fundamental studies of multiphase flow behavior in porous media. Specific objectives are divided into four subtasks: (1) development of NMRI and CT scanning for the determination of rock-fluid and petrophysical properties; (2) development of NMRI and CT scanning for characterizing conventional multiphase displacement processes; (3) development of NMR and CT scanning for characterizing dispersed phase processes; and (4) miscible displacement studies.

Barrufet, M.A.; Flumerfelt, F.W.; Walsh, M.P.; Watson, A.T.

1994-04-01T23:59:59.000Z

71

Image-Based Monitoring of Magnetic Resonance-Guided Thermoablative Therapies for Liver Tumors  

SciTech Connect

Minimally invasive treatment options for liver tumor therapy have been increasingly used during the last decade because their benefit has been proven for primary and inoperable secondary liver tumors. Among these, radiofrequency ablation has gained widespread consideration. Optimal image-guidance offers precise anatomical information, helps to position interventional devices, and allows for differentiation between already-treated and remaining tumor tissue. Patient safety and complete ablation of the entire tumor are the overriding objectives of tumor ablation. These may be achieved most elegantly with magnetic resonance (MR)-guided therapy, where monitoring can be performed based on precise soft-tissue imaging and additional components, such as diffusion-weighted imaging and temperature mapping. New MR scanner types and newly developed sequence techniques have enabled MR-guided intervention to move beyond the experimental phase. This article reviews the current role of MR imaging in guiding radiofrequency ablation. Signal characteristics of primary and secondary liver tumors are identified, and signal alteration during therapy is described. Diffusion-weighted imaging (DWI) and temperature mapping as special components of MR therapy monitoring are introduced. Practical information concerning coils, sequence selection, and parameters, as well as sequence gating, is given. In addition, sources of artifacts are identified and techniques to decrease them are introduced, and the characteristic signs of residual tumor in T1-, T2-, and DWI are described. We hope to enable the reader to choose MR sequences that allow optimal therapy monitoring depending on the initial signal characteristics of the tumor as well as its size and location in the liver.

Rempp, Hansjoerg, E-mail: hansjoerg.rempp@med.uni-tuebingen.de; Clasen, Stephan [Eberhard Karls University of Tuebingen, Department of Diagnostic and Interventional Radiology (Germany); Pereira, Philippe L. [SLK-Kliniken, Clinic for Radiology, Nuclear Medicine, and Minimal Invasive Therapies (Germany)

2012-12-15T23:59:59.000Z

72

High-Resolution Imaging and Optical Control of Bose-Einstein Condensates in an Atom Chip Magnetic Trap  

E-Print Network (OSTI)

A high-resolution projection and imaging system for ultracold atoms is implemented using a compound silicon and glass atom chip. The atom chip is metalized to enable magnetic trapping while glass regions enable high numerical aperture optical access to atoms residing in the magnetic trap about 100 microns below the chip surface. The atom chip serves as a wall of the vacuum system, which enables the use of commercial microscope components for projection and imaging. Holographically generated light patterns are used to optically slice a cigar-shaped magnetic trap into separate regions; this has been used to simultaneously generate up to four Bose-condensates. Using fluorescence techniques we have demonstrated in-trap imaging resolution down to 2.5 microns

Evan A. Salim; Seth C. Caliga; Jonathan B. Pfeiffer; Dana Z. Anderson

2012-08-24T23:59:59.000Z

73

Diffusion-Weighted Magnetic Resonance Imaging in Monitoring Rectal Cancer Response to Neoadjuvant Chemoradiotherapy  

SciTech Connect

Purpose: To prospectively monitor the response in patients with locally advanced nonmucinous rectal cancer after chemoradiotherapy (CRT) using diffusion-weighted magnetic resonance imaging. The histopathologic finding was the reference standard. Methods and Materials: The institutional review board approved the present study. A total of 62 patients (43 men and 19 women; mean age, 64 years; range, 28-83) provided informed consent. T{sub 2}- and diffusion-weighted magnetic resonance imaging scans (b value, 0 and 1,000 mm{sup 2}/s) were acquired before, during (mean 12 days), and 6-8 weeks after CRT. We compared the median apparent diffusion coefficients (ADCs) between responders and nonresponders and examined the associations with the Mandard tumor regression grade (TRG). The postoperative nodal status (ypN) was evaluated. The Mann-Whitney/Wilcoxon two-sample test was used to evaluate the relationships among the pretherapy ADCs, extramural vascular invasion, early percentage of increases in ADCs, and preoperative ADCs. Results: Low pretreatment ADCs (<1.0 Multiplication-Sign 10{sup -3}mm{sup 2}/s) were correlated with TRG 4 scores (p = .0011) and associated to extramural vascular invasion with ypN+ (85.7% positive predictive value for ypN+). During treatment, the mean percentage of increase in tumor ADC was significantly greater in the responders than in the nonresponders (p < .0001) and a >23% ADC increase had a 96.3% negative predictive value for TRG 4. In 9 of 16 complete responders, CRT-related tumor downsizing prevented ADC evaluations. The preoperative ADCs were significantly different (p = .0012) between the patients with and without downstaging (preoperative ADC {>=}1.4 Multiplication-Sign 10{sup -3}mm{sup 2}/s showed a positive and negative predictive value of 78.9% and 61.8%, respectively, for response assessment). The TRG 1 and TRG 2-4 groups were not significantly different. Conclusion: Diffusion-weighted magnetic resonance imaging seems to be a promising tool for monitoring the response to CRT.

Barbaro, Brunella, E-mail: bbarbaro@rm.unicatt.it [Department of Bioimaging and Radiological Sciences, Catholic University School of Medicine, Rome (Italy); Vitale, Renata; Valentini, Vincenzo; Illuminati, Sonia [Department of Bioimaging and Radiological Sciences, Catholic University School of Medicine, Rome (Italy); Vecchio, Fabio M. [Department of Pathology, Catholic University School of Medicine, Rome (Italy); Rizzo, Gianluca [Department of Surgery, Catholic University School of Medicine, Rome (Italy); Gambacorta, Maria Antonietta [Department of Bioimaging and Radiological Sciences, Catholic University School of Medicine, Rome (Italy); Coco, Claudio; Crucitti, Antonio; Persiani, Roberto; Sofo, Luigi [Department of Surgery, Catholic University School of Medicine, Rome (Italy); Bonomo, Lorenzo [Department of Bioimaging and Radiological Sciences, Catholic University School of Medicine, Rome (Italy)

2012-06-01T23:59:59.000Z

74

Point sensitive NMR imaging system using a magnetic field configuration with a spatial minimum  

DOE Patents (OSTI)

A point-sensitive NMR imaging system (10) in which a main solenoid coil (11) produces a relatively strong and substantially uniform magnetic field and a pair of perturbing coils (PZ1 and PZ2) powered by current in the same direction superimposes a pair of relatively weak perturbing fields on the main field to produce a resultant point of minimum field strength at a desired location in a direction along the Z-axis. Two other pairs of perturbing coils (PX1, PX2; PY1, PY2) superimpose relatively weak field gradients on the main field in directions along the X- and Y-axes to locate the minimum field point at a desired location in a plane normal to the Z-axes. An RF generator (22) irradiates a tissue specimen in the field with radio frequency energy so that desired nuclei in a small volume at the point of minimum field strength will resonate.

Eberhard, Philippe H. (El Cerrito, CA)

1985-01-01T23:59:59.000Z

75

Nuclear magnetic resonance imaging and analysis for determination of porous media properties  

E-Print Network (OSTI)

Advanced nuclear magnetic resonance (NMR) imaging methodologies have been developed to determine porous media properties associated with fluid flow processes. This dissertation presents the development of NMR experimental and analysis methodologies, called NMR probes, particularly for determination of porosity, permeability, and pore-size distributions of porous media while the developed methodologies can be used for other properties. The NMR relaxation distribution can provide various information about porous systems having NMR active nuclei. The determination of the distribution from NMR relaxation data is an ill-posed inverse problem that requires special care, but conventionally the problem has been solved by ad-hoc methods. We have developed a new method based on sound statistical theory that suitably implements smoothness and equality/inequality constraints. This method is used for determination of porosity distributions. A Carr-Purcell-Meiboom-Gill (CPMG) NMR experiment is designed to measure spatially resolved NMR relaxation data. The determined relaxation distribution provides the estimate of intrinsic magnetization which, in turn, is scaled to porosity. A pulsed-field-gradient stimulated-echo (PFGSTE) NMR velocity imaging experiment is designed to measure the superficial average velocity at each volume element. This experiment measures velocity number distributions as opposed to the average phase shift, which is conventionally measured, to suitably quantify the velocities within heterogeneous porous media. The permeability distributions are determined by solving the inverse problem formulated in terms of flow models and the velocity data. We present new experimental designs associated with flow conditions to enhance the accuracy of the estimates. Efforts have been put forth to further improve the accuracy by introducing and evaluating global optimization methods. The NMR relaxation distribution can be scaled to a pore-size distribution once the surface relaxivity is known. We have developed a new method, which avoids limitations on the range of time for which data may be used, to determine surface relaxivity by the PFGSTE NMR diffusion experiment.

Uh, Jinsoo

2005-12-01T23:59:59.000Z

76

Dynamic Contrast-Enhanced Magnetic Resonance Imaging of the Metastatic Potential of Melanoma Xenografts  

SciTech Connect

Purpose: Gadolinium diethylene-triamine penta-acetic acid (Gd-DTPA)-based dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has been suggested as a useful noninvasive method for characterizing the physiologic microenvironment of tumors. In the present study, we investigated whether Gd-DTPA-based DCE-MRI has the potential to provide biomarkers for hypoxia-associated metastatic dissemination. Methods and Materials: C-10 and D-12 melanoma xenografts were used as experimental tumor models. Pimonidazole was used as a hypoxia marker. A total of 60 tumors were imaged, and parametric images of K{sup trans} (volume transfer constant of Gd-DTPA) and v{sub e} (fractional distribution volume of Gd-DTPA) were produced by pharmacokinetic analysis of the DCE-MRI series. The host mice were killed immediately after DCE-MRI, and the primary tumor and the lungs were resected and prepared for histologic assessment of the fraction of pimonidazole-positive hypoxic tissue and the presence of lung metastases, respectively. Results: Metastases were found in 11 of 26 mice with C-10 tumors and 14 of 34 mice with D-12 tumors. The primary tumors of the metastatic-positive mice had a greater fraction of hypoxic tissue (p = 0.00031, C-10; p < 0.00001, D-12), a lower median K{sup trans} (p = 0.0011, C-10; p < 0.00001, D-12), and a lower median v{sub e} (p = 0.014, C-10; p = 0.016, D-12) than the primary tumors of the metastatic-negative mice. Conclusions: These findings support the clinical attempts to establish DCE-MRI as a method for providing biomarkers for tumor aggressiveness and suggests that primary tumors characterized by low K{sup trans} and low v{sub e} values could have a high probability of hypoxia-associated metastatic spread.

Ovrebo, Kirsti Marie; Ellingsen, Christine; Galappathi, Kanthi [Group of Radiation Biology and Tumor Physiology, Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, Oslo (Norway); Rofstad, Einar K., E-mail: einar.k.rofstad@rr-research.no [Group of Radiation Biology and Tumor Physiology, Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, Oslo (Norway)

2012-05-01T23:59:59.000Z

77

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

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

new materials with new switching mechanisms. Uncovered by basic research into the fundamentals of magnetism, one such candidate consists of miniscule magnetic vortices like...

78

Resolving the Impact of Biological Processes on Water Transport in Unsaturated Porous Media Through Nuclear Magnetic Resonance Micro-Imaging  

DOE Green Energy (OSTI)

The magnetic resonance microscopy (MRM) work at Montana State University has extended the imaging of a single biofilm in a 1 mm capillary reactor to correlate T2 magnetic relaxation maps displaying biofilm structure with the corresponding velocity patterns in three dimensions in a Staphylococcus epidermidis biofilm fouled square capillary. A square duct geometry is chosen to provide correlation with existing experiments and simulations, as research bioreactors tend to be of square or rectangular cross section for optical or microelectrode access. The spatially resolved velocity data provide details on the impact of biofilm induced advection on mass transport from the bulk fluid to the biofilm and through the capillary bioreactor.

Seymour, Joseph D.

2005-06-01T23:59:59.000Z

79

A survey of prostate segmentation methodologies in ultrasound, magnetic resonance and computed tomography images  

Science Conference Proceedings (OSTI)

Prostate segmentation is a challenging task, and the challenges significantly differ from one imaging modality to another. Low contrast, speckle, micro-calcifications and imaging artifacts like shadow poses serious challenges to accurate prostate segmentation ... Keywords: CT images, MR images, Prostate gland segmentation methods, TRUS images

Soumya Ghose; Arnau Oliver; Robert Mart; Xavier Llad; Joan C. Vilanova; Jordi Freixenet; Jhimli Mitra; DSir Sidib; Fabrice Meriaudeau

2012-10-01T23:59:59.000Z

80

Discrete magic angle turning system, apparatus, and process for in situ magnetic resonance spectroscopy and imaging  

DOE Patents (OSTI)

Described are a "Discrete Magic Angle Turning" (DMAT) system, devices, and processes that combine advantages of both magic angle turning (MAT) and magic angle hopping (MAH) suitable, e.g., for in situ magnetic resonance spectroscopy and/or imaging. In an exemplary system, device, and process, samples are rotated in a clockwise direction followed by an anticlockwise direction of exactly the same amount. Rotation proceeds through an angle that is typically greater than about 240 degrees but less than or equal to about 360 degrees at constant speed for a time applicable to the evolution dimension. Back and forth rotation can be synchronized and repeated with a special radio frequency (RF) pulse sequence to produce an isotropic-anisotropic shift 2D correlation spectrum. The design permits tubes to be inserted into the sample container without introducing plumbing interferences, further allowing control over such conditions as temperature, pressure, flow conditions, and feed compositions, thus permitting true in-situ investigations to be carried out.

Hu, Jian Zhi (Richland, WA); Sears, Jr., Jesse A. (Kennewick, WA); Hoyt, David W. (Richland, WA); Wind, Robert A. (Kennewick, WA)

2009-05-19T23:59:59.000Z

Note: This page contains sample records for the topic "imaging current-driven magnetic" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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to obtain the most current and comprehensive results.


81

MAGNETIC RESONANCE ELECTRICAL IMPEDANCE TOMOGRAPHY (MR-EIT): A new technique for high resolution conductivity imaging  

E-Print Network (OSTI)

to a conductor generates a constant magnetic field with flux density jB r . If the current carrying conductor potentials and the magnetic fields produced by the probing current are measured. Surface potentials and the point spread function is not space invariant. On the other hand, magnetic field and electrical current

Eyüboðlu, Murat

82

Radiation-Induced Damage to Microstructure of Parotid Gland: Evaluation Using High-Resolution Magnetic Resonance Imaging  

SciTech Connect

Purpose: To elucidate the radiation-induced damage to the microstructure of the parotid gland using high-resolution magnetic resonance imaging. Methods and Materials: High-resolution magnetic resonance imaging of the parotid gland was performed before radiotherapy (RT) and during the RT period or {<=}3 weeks after RT completion for 12 head-and-neck cancer patients using a 1.5-T scanner with a microscopy coil. The maximal cross-sectional area of the gland was evaluated, and changes in the internal architecture of the gland were assessed both visually and quantitatively. Results: Magnetic resonance images were obtained at a median parotid gland dose of 36 Gy (range, 11-64). According to the quantitative analysis, the maximal cross-sectional area of the gland was reduced, the width of the main duct was narrowed, and the intensity ratio of the main duct lumen to background was significantly decreased after RT (p <.0001). According to the visual assessment, the width of the main duct tended to narrow and the contrast of the duct lumen tended to be decreased, but no significant differences were noted. The visibility of the duct branches was unclear in 10 patients (p = .039), and the septum became dense in 11 patients (p = .006) after RT. Conclusion: High-resolution magnetic resonance imaging is a noninvasive method of evaluating radiation-induced changes to the internal architecture of the parotid gland. Morphologic changes in the irradiated parotid gland were demonstrated during the RT course even when a relatively small dose was delivered to the gland.

Kan, Tomoko, E-mail: tkan@grape.med.tottori-u.ac.j [Department of Radiology, Tottori University Faculty of Medicine, Yonago, Tottori (Japan); Kodani, Kazuhiko; Michimoto, Koichi; Fujii, Shinya; Ogawa, Toshihide [Department of Radiology, Tottori University Faculty of Medicine, Yonago, Tottori (Japan)

2010-07-15T23:59:59.000Z

83

Magnetic force microscopy method and apparatus to detect and image currents in integrated circuits  

DOE Patents (OSTI)

A magnetic force microscopy method and improved magnetic tip for detecting and quantifying internal magnetic fields resulting from current of integrated circuits. Detection of the current is used for failure analysis, design verification, and model validation. The interaction of the current on the integrated chip with a magnetic field can be detected using a cantilevered magnetic tip. Enhanced sensitivity for both ac and dc current and voltage detection is achieved with voltage by an ac coupling or a heterodyne technique. The techniques can be used to extract information from analog circuits.

Campbell, Ann. N. (13170-B Central SE #188, Albuquerque, NM 87123); Anderson, Richard E. (2800 Tennessee NE, Albuquerque, NM 87110); Cole, Jr., Edward I. (2116 White Cloud NE, Albuquerque, NM 87112)

1995-01-01T23:59:59.000Z

84

Optimizing a low-energy electron diffraction spin-polarization analyzer for imaging of magnetic surface structures  

Science Conference Proceedings (OSTI)

A newly designed scanning electron microscope with polarization analysis (SEMPA or spin-SEM) for the acquisition of magnetic images is presented. Core component is the spin detector, based on the scattering of low-energy electrons at a W(100) surface in ultrahigh vacuum. The instrument has been optimized with respect to ease of handling and efficiency. The operation and performance of a general low-energy electron diffraction (LEED) detector for SEMPA have been modeled in order to find the optimum operating parameters and to predict the obtainable image asymmetry. Based on the energy dependence of the secondary electron polarization and intensity, the detector output is simulated. For our instrument with optimized performance we demonstrate experimentally 8.6% polarization asymmetry in the domain structure of an iron whisker. This corresponds to 17.2% image contrast, in excellent agreement with the predicted simulated value. A contrast to noise ratio of 27 is achieved at 5 ms acquisition time per pixel.

Froemter, Robert; Hankemeier, Sebastian; Oepen, Hans Peter [Institut fuer Angewandte Physik, Universitaet Hamburg, Jungiusstr. 11, 20355 Hamburg (Germany); Kirschner, Juergen [Max-Planck-Institut fuer Mikrostrukturphysik, Weinberg 2, 06120 Halle (Germany)

2011-03-15T23:59:59.000Z

85

Nuclear magnetic resonance apparatus having semitoroidal rf coil for use in topical NMR and NMR imaging  

DOE Patents (OSTI)

An improved nuclear magnetic resonance (NMR) apparatus for use in topical magnetic resonance (TMR) spectroscopy and other remote sensing NMR applications includes a semitoroidal radio-frequency (rf) coil. The semitoroidal rf coil produces an effective alternating magnetic field at a distance from the poles of the coil, so as to enable NMR measurements to be taken from selected regions inside an object, particularly including human and other living subjects. The semitoroidal rf coil is relatively insensitive to magnetic interference from metallic objects located behind the coil, thereby rendering the coil particularly suited for use in both conventional and superconducting NMR magnets. The semitoroidal NMR coil can be constructed so that it emits little or no excess rf electric field associated with the rf magnetic field, thus avoiding adverse effects due to dielectric heating of the sample or to any other interaction of the electric field with the sample.

Fukushima, Eiichi (Los Alamos, NM); Roeder, Stephen B. W. (La Mesa, CA); Assink, Roger A. (Albuquerque, NM); Gibson, Atholl A. V. (Bryan, TX)

1986-01-01T23:59:59.000Z

86

HST.583 Functional Magnetic Resonance Imaging: Data Acquisition and Analysis, Fall 2002  

E-Print Network (OSTI)

Provides information relevant to the conduct and interpretation of human brain mapping studies. Provides in-depth coverage of the physics of image formation, mechanisms of image contrast, and the physiological basis for ...

Gollub, Randy L.

87

HST.583 Functional Magnetic Resonance Imaging: Data Acquisition and Analysis, Fall 2004  

E-Print Network (OSTI)

Provides information relevant to the conduct and interpretation of human brain mapping studies. Provides in-depth coverage of the physics of image formation, mechanisms of image contrast, and the physiological basis for ...

Gollub, Randy L.

88

Soft x-ray microscopy - a powerful analytical tool to image magnetism down to fundamental length and times scales  

Science Conference Proceedings (OSTI)

The magnetic properties of low dimensional solid state matter is of the utmost interest both scientifically as well as technologically. In addition to the charge of the electron which is the base for current electronics, by taking into account the spin degree of freedom in future spintronics applications open a new avenue. Progress towards a better physical understanding of the mechanism and principles involved as well as potential applications of nanomagnetic devices can only be achieved with advanced analytical tools. Soft X-ray microscopy providing a spatial resolution towards 10nm, a time resolution currently in the sub-ns regime and inherent elemental sensitivity is a very promising technique for that. This article reviews the recent achievements of magnetic soft X-ray microscopy by selected examples of spin torque phenomena, stochastical behavior on the nanoscale and spin dynamics in magnetic nanopatterns. The future potential with regard to addressing fundamental magnetic length and time scales, e.g. imaging fsec spin dynamics at upcoming X-ray sources is pointed out.

Fischer, Peter

2008-08-01T23:59:59.000Z

89

magnets  

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

I I Painless Physics Articles BEAM COOLING August 2, 1996 By Leila Belkora, Office of Public Affairs ACCELERATION August 16, 1996 By Dave Finley, Accelerator Division Head RF August 30, 1996 By Pat Colestock, Accelerator Division FIXED TARGET PHYSICS September 20, 1996 By Peter H. Garbincius, Physics Section FIXED TARGET PHYSICS PART DEUX October 16, 1996 By Peter H. Garbincius, Physics Section and Leila Belkora, Office of Public Affaris CROSS SECTION November 1, 1996 By Doreen Wackeroth, Theoretical Physics Edited by Leila Belkora, Office of Public Affaris MAGNETS PART I November 15, 1996 By Hank Glass, Technical Support Section Edited by Donald Sena, Office of Public Affairs MAGNETS PART II January 10, 1997 By Hank Glass, Technical Support Section Edited by Donald Sena, Office of Public Affairs

90

PUBLISHED ONLINE: 31 MAY 2009 | DOI: 10.1038/NPHYS1300 Experimental onset threshold and magnetic  

E-Print Network (OSTI)

current channels (flux ropes) driven by magnetohydrodynamic (MHD) attraction and a 3D plasma-current-driven instability. Antiparallel magnetic field lines carried by these colliding flux ropes annihilate and drive an electric field. The inflow soon exceeds a threshold for the formation of a reconnection current layer

Loss, Daniel

91

Probing the spin polarization of current by soft x-ray imaging of current-induced magnetic vortex dynamics  

SciTech Connect

Time-resolved soft X-ray transmission microscopy is applied to image the current-induced resonant dynamics of the magnetic vortex core realized in a micron-sized Permalloy disk. The high spatial resolution better than 25 nm enables us to observe the resonant motion of the vortex core. The result also provides the spin polarization of the current to be 0.67 {+-} 0.16 for Permalloy by fitting the experimental results with an analytical model in the framework of the spin-transfer torque.

Kasai, Shinya; Fischer, Peter; Im, Mi-Young; Yamada, Keisuke; Nakatani, Yoshinobu; Kobayashi, Kensuke; Kohno, Hiroshi; Ono, Teruo

2008-12-09T23:59:59.000Z

92

Method for nuclear magnetic resonance imaging using deuterum as a contrast agent  

DOE Patents (OSTI)

A method for in vivo NMR imaging of the blood vessels and organs of a patient characterized by using a dark dye-like imaging substance consisting essentially of a stable, high-purity concentration of D.sub.2 O in a solution with water.

Kehayias, Joseph J. (Chestnut Hill, MA); Joel, Darrel D. (Setauket, NY); Adams, William H. (Eastport, NY); Stein, Harry L. (Glen Head, NY)

1990-01-01T23:59:59.000Z

93

Spheromak Formation and Sustainment Studies at the Sustained Spheromak Physics Experiment Using High-Speed Imaging and Magnetic Diagnostics  

DOE Green Energy (OSTI)

A high-speed imaging system with shutter speeds as fast as 2 ns and double frame capability has been used to directly image the formation and evolution of the Sustained Spheromak Physics Experiment (SSPX). Reproducible plasma features have been identified with this diagnostic and divided in three groups, according to the stage in the discharge at which they occur: (1) breakdown and ejection, (2) sustainment, and (3) decay. During the first stage, plasma descends into the flux conserver shortly after breakdown and a transient plasma column is formed. The column then rapidly bends and simultaneously becomes too dim to photograph a few microseconds after formation. We conjecture that this rapid bending precedes the transfer of toroidal to poloidal flux. During sustainment, a stable plasma column different from the transient one is observed. It has been possible to measure the column diameter and compare it to CORSICA, an MHD equilibrium reconstruction code which showed good agreement with the measurements. Elongation and velocity measurements were made of cathode patterns also seen during this stage, possibly caused by pressure gradients or E x B drifts. The patterns elongate in a toroidal-only direction which depends on the magnetic field polarity. During the decay stage the column diameter expands as the current ramps down, until it eventually dissolves into filaments. With the use of magnetic probes inserted in the gun region, a X-point which moved axially depending on current level and toroidal mode number, was observed in all the stages of the SSPX plasma discharge.

Romero-Talamas, C A; Holcomb, C; Bellan, P M; Hill, D N

2005-11-09T23:59:59.000Z

94

Magnetic Materials Group Homepage  

Science Conference Proceedings (OSTI)

... and simulation to become the driving force in ... develop a real-time magnetic domain imaging ... data-storage and permanent magnets with increased ...

2012-12-03T23:59:59.000Z

95

Combination of diffusion tensor and functional magnetic resonance imaging during recovery from the vegetative state.  

E-Print Network (OSTI)

in functional neuroimaging. J Cogn Neurosci 2003, 15:394-408. 35. Genovese CR, Lazar NA, Nichols T: Thresholding of statistical maps in functional neuroimaging using the false discovery rate. NeuroImage 2002, 15:870-878. 36. Vigneau M, Beaucousin V, Herv PY...

Fernandez-Espejo, Davinia; Junque, Carme; Cruse, Damian; Bernabeu, Montserrat; Roig-Rovira, Teresa; Fabregas, Neus; Rivas, Eva; Mercader, Jose M

2010-09-03T23:59:59.000Z

96

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Magneto-optical image of magnetic fields within a YBCO superconductor showing electrically ... PHY, High-Temp Superconductors See also http ...

97

Abstract-In this study, imaging of electrical current density in conducting objects, which contain nuclear magnetic resonance  

E-Print Network (OSTI)

at each cycle within the object. The applied current pulse creates a measurable magnetic flux density. The component of magnetic flux density parallel to the main magnetic field accumulates an additional phase with and without the current pulse. Measurement of all three components of magnetic flux density makes

Eyüboðlu, Murat

98

Minimally Invasive Magnetic Resonance Imaging-Guided Free-Hand Aspiration of Symptomatic Nerve Route Compressing Lumbosacral Cysts Using a 1.0-Tesla Open Magnetic Resonance Imaging System  

SciTech Connect

Purpose: To evaluate the feasibility of minimally invasive magnetic resonance imaging (MRI)-guided free-hand aspiration of symptomatic nerve route compressing lumbosacral cysts in a 1.0-Tesla (T) open MRI system using a tailored interactive sequence. Materials and Methods: Eleven patients with MRI-evident symptomatic cysts in the lumbosacral region and possible nerve route compressing character were referred to a 1.0-T open MRI system. For MRI interventional cyst aspiration, an interactive sequence was used, allowing for near real-time position validation of the needle in any desired three-dimensional plane. Results: Seven of 11 cysts in the lumbosacral region were successfully aspirated (average 10.1 mm [SD {+-} 1.9]). After successful cyst aspiration, each patient reported speedy relief of initial symptoms. Average cyst size was 9.6 mm ({+-}2.6 mm). Four cysts (8.8 {+-} 3.8 mm) could not be aspirated. Conclusion: Open MRI systems with tailored interactive sequences have great potential for cyst aspiration in the lumbosacral region. The authors perceive major advantages of the MR-guided cyst aspiration in its minimally invasive character compared to direct and open surgical options along with consecutive less trauma, less stress, and also less side-effects for the patient.

Bucourt, Maximilian de, E-mail: mdb@charite.de; Streitparth, Florian, E-mail: florian.streitparth@charite.de; Collettini, Federico [Charite-University Medicine, Department of Radiology (Germany); Guettler, Felix [Jena University, Department of Radiology (Germany); Rathke, Hendrik; Lorenz, Britta; Rump, Jens; Hamm, Bernd [Charite-University Medicine, Department of Radiology (Germany); Teichgraeber, U. K. [Jena University, Department of Radiology (Germany)

2012-02-15T23:59:59.000Z

99

Magnetic Resonance Imaging-Guided Osseous Biopsy in Children With Chronic Recurrent Multifocal Osteomyelitis  

SciTech Connect

Purpose: To report the safety and diagnostic performance of magnetic resonance (MRI)-guided core biopsy of osseous lesions in children with chronic recurrent multifocal osteomyelitis (CRMO) that were visible on MRI but were occult on radiography and computed tomography (CT). Materials and Methods: A retrospective analysis of MRI-guided osseous biopsy performed in seven children (four girls and three boys; mean age 13 years (range 11 to 14) with CRMO was performed. Indication for using MRI guidance was visibility of lesions by MRI only. MRI-guided procedures were performed with 0.2-Tesla (Magnetom Concerto; Siemens, Erlangen, Germany; n = 5) or 1.5-T (Magnetom Espree; Siemens; n = 2) open MRI systems. Core needle biopsy was obtained using an MRI-compatible 4-mm drill system. Conscious sedation or general anesthesia was used. Parameters evaluated were lesion visibility, technical success, procedure time, complications and microbiology, cytology, and histopathology findings. Results: Seven of seven (100%) targeted lesions were successfully visualized and sampled. All obtained specimens were sufficient for histopathological analysis. Length of time of the procedures was 77 min (range 64 to 107). No complications occurred. Histopathology showed no evidence of malignancy, which was confirmed at mean follow-up of 50 months (range 28 to 78). Chronic nonspecific inflammation characteristic for CRMO was present in four of seven (58%) patients, and edema with no inflammatory cells was found in three of seven (42%) patients. There was no evidence of infection in any patient. Conclusion: MRI-guided osseous biopsy is a safe and accurate technique for the diagnosis of pediatric CRMO lesions that are visible on MRI only.

Fritz, Jan, E-mail: jfritz9@jhmi.edu [Johns Hopkins University School of Medicine, Russell H. Morgan Department of Radiology and Radiological Science (United States); Tzaribachev, Nikolay [University Children's Hospital, Eberhard-Karls-University Tuebingen, Division of Pediatric Rheumatology (Germany); Thomas, Christoph [Eberhard-Karls-University Tuebingen, Department of Diagnostic and Interventional Radiology (Germany); Wehrmann, Manfred [Eberhard-Karls-University Tuebingen, Department of Pathology (Germany); Horger, Marius S. [Eberhard-Karls-University Tuebingen, Department of Diagnostic and Interventional Radiology (Germany); Carrino, John A. [Johns Hopkins University School of Medicine, Russell H. Morgan Department of Radiology and Radiological Science (United States); Koenig, Claudius W.; Pereira, Philippe L. [Eberhard-Karls-University Tuebingen, Department of Diagnostic and Interventional Radiology (Germany)

2012-02-15T23:59:59.000Z

100

A Signal-Inducing Bone Cement for Magnetic Resonance Imaging-Guided Spinal Surgery Based on Hydroxyapatite and Polymethylmethacrylate  

Science Conference Proceedings (OSTI)

The aim of this study was to develop a signal-inducing bone cement for magnetic resonance imaging (MRI)-guided cementoplasty of the spine. This MRI cement would allow precise and controlled injection of cement into pathologic lesions of the bone. We mixed conventional polymethylmethacrylate bone cement (PMMA; 5 ml methylmethacrylate and 12 g polymethylmethacrylate) with hydroxyapatite (HA) bone substitute (2-4 ml) and a gadolinium-based contrast agent (CA; 0-60 {mu}l). The contrast-to-noise ratio (CNR) of different CA doses was measured in an open 1.0-Tesla scanner for fast T1W Turbo-Spin-Echo (TSE) and T1W TSE pulse sequences to determine the highest signal. We simulated MRI-guided cementoplasty in cadaveric spines. Compressive strength of the cements was tested. The highest CNR was (1) 87.3 (SD 2.9) in fast T1W TSE for cements with 4 {mu}l CA/ml HA (4 ml) and (2) 60.8 (SD 2.4) in T1W TSE for cements with 1 {mu}l CA/ml HA (4 ml). MRI-guided cementoplasty in cadaveric spine was feasible. Compressive strength decreased with increasing amounts of HA from 46.7 MPa (2 ml HA) to 28.0 MPa (4 ml HA). An MRI-compatible cement based on PMMA, HA, and CA is feasible and clearly visible on MRI images. MRI-guided spinal cementoplasty using this cement would permit direct visualization of the cement, the pathologic process, and the anatomical surroundings.

Wichlas, Florian, E-mail: florian.wichlas@charite.de; Seebauer, Christian J.; Schilling, Rene [University Charite, Center for Musculoskeletal Surgery (Germany); Rump, Jens [University Charite, Department of Radiology (Germany); Chopra, Sascha S. [University Charite, Center for Musculoskeletal Surgery (Germany); Walter, Thula; Teichgraeber, Ulf K. M. [University Charite, Department of Radiology (Germany); Bail, Hermann J. [University Charite, Center for Musculoskeletal Surgery (Germany)

2012-06-15T23:59:59.000Z

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101

Imaging  

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

Imaging Print Imaging Print The wavelengths of soft x-ray photons (1-15 nm) are very well matched to the creation of "nanoscopes" capable of probing the interior structure of biological cells and inorganic mesoscopic systems.Topics addressed by soft x-ray imaging techniques include cell biology, nanomagnetism, environmental science, and polymers. The tunability of synchrotron radiation is absolutely essential for the creation of contrast mechanisms. Cell biology CAT scans are performed in the "water window" (300-500 eV). Nanomagnetism studies require the energy range characteristic of iron, cobalt, and nickel (600-900 eV). Mid- and far-infrared (energies below 1 eV) microprobes using synchrotron radiation are being used to address problems such as chemistry in biological tissues, chemical identification and molecular conformation, environmental biodegradation, mineral phases in geological and astronomical specimens, and electronic properties of novel materials. Infrared synchrotron radiation is focused through, or reflected from, a small spot on the specimen and then analyzed using a spectrometer. Tuning to characteristic vibrational frequencies serves as a sensitive fingerprint for molecular species. Images of the various species are built up by raster scanning the specimen through the small illuminated spot.

102

Improved nuclear magnetic resonance apparatus having semitoroidal rf coil for use in topical NMR and NMR imaging  

DOE Patents (OSTI)

An improved nuclear magnetic resonance (NMR) apparatus for use in topical magnetic resonance (TMR) spectroscopy and other remote sensing NMR applications includes a semitoroidal radio frequency (rf) coil. The semitoroidal rf coil produces an effective alternating magnetic field at a distance from the poles of the coil, so as to enable NMR measurements to be taken from selected regions inside an object, particularly including human and other living subjects. The semitoroidal rf coil is relatively insensitive to magnetic interference from metallic objects located behind the coil, thereby rendering the coil particularly suited for use in both conventional and superconducting NMR magnets. The semitoroidal NMR coil can be constructed so that it emits little or no excess rf electric field associated with the rf magnetic field, thus avoiding adverse effects due to dielectric heating of the sample or to any other interaction of the electric field with the sample.

Fukushima, E.; Roeder, S.B.W.; Assink, R.A.; Gibson, A.A.V.

1984-01-01T23:59:59.000Z

103

Nuclear magnetic resonance contrast agents  

DOE Patents (OSTI)

This invention relates to the field of nuclear magnetic resonance imaging and nuclear magnetic resonance spectroscopy, also known simply as magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS). MRI and MRS are particularly useful in medical research and diagnosis. MRI may be used in addition to x-ray imaging. This invention concerns 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. 2 figs.

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

1989-01-24T23:59:59.000Z

104

Mapping the Flip Angle in Magnetic Resonance Imaging Using the Accelerated 3D Look-Locker Sequence.  

E-Print Network (OSTI)

??In the ongoing quest to extract more information from MRI images, there has arisen a need to rapidly map the flip angle. This has been (more)

Wade, Trevor P

2010-01-01T23:59:59.000Z

105

Near-Electrode Imager  

DOE Patents (OSTI)

An apparatus, near-electrode imager, for employing nuclear magnetic resonance imaging to provide in situ measurements of electrochemical properties of a sample as a function of distance from a working electrode. The near-electrode imager use the radio frequency field gradient within a cylindrical toroid cavity resonator to provide high-resolution nuclear magnetic resonance spectral information on electrolyte materials.

Rathke, Jerome W.; Klingler, Robert J.; Woelk, Klaus; Gerald, Rex E.,II

1999-05-01T23:59:59.000Z

106

Advanced Measurement Laboratory Image Gallery  

Science Conference Proceedings (OSTI)

... This NIST-developed instrument, a scanning electron microscope with spin polarization analysis, is the highest resolution magnetization imaging ...

2010-10-05T23:59:59.000Z

107

The evolution of magnetic tower jets in the laboratory  

E-Print Network (OSTI)

The evolution of laboratory produced magnetic jets is followed numerically through three-dimensional, non-ideal magnetohydrodynamic simulations. The experiments are designed to study the interaction of a purely toroidal field with an extended plasma background medium. The system is observed to evolve into a structure consisting of an approximately cylindrical magnetic cavity with an embedded magnetically confined jet on its axis. The supersonic expansion produces a shell of swept-up shocked plasma which surrounds and partially confines the magnetic tower. Currents initially flow along the walls of the cavity and in the jet but the development of current-driven instabilities leads to the disruption of the jet and a re-arrangement of the field and currents. The top of the cavity breaks-up and a well collimated, radiatively cooled, 'clumpy' jet emerges from the system.

A. Ciardi; S. V. Lebedev; A. Frank; E. G. Blackman; J. P. Chittenden; C. J. Jennings; D. J. Ampleford; S. N. Bland; S. C. Bott; J. Rapley; G. N. Hall; F. A. Suzuki-Vidal; A. Marocchino; T. Lery; C. Stehle

2006-11-14T23:59:59.000Z

108

Time--Distance Helioseismology Data Analysis Pipeline for Helioseismic and Magnetic Imager onboard Solar Dynamics Observatory (SDO/HMI) and Its Initial Results  

E-Print Network (OSTI)

The Helioseismic and Magnetic Imager onboard the Solar Dynamics Observatory (SDO/HMI) provides continuous full-disk observations of solar oscillations. We develop a data-analysis pipeline based on the time-distance helioseismology method to measure acoustic travel times using HMI Doppler-shift observations, and infer solar interior properties by inverting these measurements. The pipeline is used for routine production of near-real-time full-disk maps of subsurface wave-speed perturbations and horizontal flow velocities for depths ranging from 0 to 20 Mm, every eight hours. In addition, Carrington synoptic maps for the subsurface properties are made from these full-disk maps. The pipeline can also be used for selected target areas and time periods. We explain details of the pipeline organization and procedures, including processing of the HMI Doppler observations, measurements of the travel times, inversions, and constructions of the full-disk and synoptic maps. Some initial results from the pipeline, includin...

Zhao, J; Bogart, R S; Parchevsky, K V; Birch, A C; Duvall, T L; Beck, J G; Kosovichev, A G; Scherrer, P H

2011-01-01T23:59:59.000Z

109

Magnetic Field Morphology of Orion-IRc2 from 86 GHz SiO Maser Polarization Images  

E-Print Network (OSTI)

In an attempt to probe the magnetic field morphology near the massive young star Orion-IRc2, we mapped the linear polarization of its J=2-1 SiO masers, in both the v=0 and v=1 vibrational levels, with 0.5 arcsec resolution. The intense v=1 masers are confined to a narrow zone 40 AU from the star. Their polarization position angles vary significantly on time scales of years. For the v=1 masers the stimulated emission rate R is likely to exceed the Zeeman splitting g\\Omega due to any plausible magnetic field; in this case the maser polarization need not correlate with the field direction. The much weaker v=0 masers in the ground vibrational level lie 100-700 AU from IRc2, in what appears to be a flared disk. Their fractional polarizations are as high as 50%. The polarization position angles vary little across the line profile or the emission region, and appear to be stable in time. The position angle, P.A. = 80 degrees, we measure for the J=2-1 masers differs by 70 degrees from that measured for the J=1-0 SiO transition, possibly because of Faraday rotation in the foreground, Orion A, HII region. A rotation measure RM = 3.3 \\times 10^4 rad m$^{-2}$ is required to bring the J=2-1 and J=1-0 position angles into concordance. The intrinsic polarization position angle for both transitions is then 57 degrees, parallel to the plane of the putative disk. Probably the magnetic field threads the disk poloidally. There is little evidence for a pinched or twisted field near the star.

R. L. Plambeck; M. C. H. Wright; R. Rao

2003-07-03T23:59:59.000Z

110

A functional magnetic resonance imaging study of overt letter verbal fluency using a clustered acquisition sequence: greater anterior cingulate activation with increased task demand  

E-Print Network (OSTI)

Regional cerebral activation during a cognitive task can vary with task demand and task performance. In a functional magnetic resonance imaging study, we examined the effect of manipulating task demand on activation during verbal fluency by using easy and hard letters. A clustered image acquisition sequence allowed overt verbal responses to be made in the absence of scanner noise which facilitated online measurement of task performance. Eleven righthanded, healthy male volunteers participated. Twice as many errors were produced with hard as with easy letters (20.8 ? 13.6 and 10.1 ? 10.7 % errors, respectively). For both conditions, the distribution of regional activation was comparable to that reported in studies of covert verbal fluency, but with greater engagement of subcortical areas. The hard condition was associated with greater dorsal anterior cingulate activation than the easy condition. This may reflect the greater demands of the former, particularly in terms of arousal responses with increased task difficulty and the monitoring of potential response errors. 2002 Elsevier Science (USA)

Cynthia H. Y. Fu; Kevin Morgan; John Suckling; Steve C. R. Williams; Chris Andrew; Goparlen N. Vythelingum; Philip K. Mcguire

2002-01-01T23:59:59.000Z

111

Novel motor design for rotating anode x-ray tubes operating in the fringe field of a magnetic resonance imaging system  

SciTech Connect

Purpose: Using hybrid x-ray/MR (XMR) systems for image guidance during interventional procedures could enhance the diagnosis and treatment of neurologic, oncologic, cardiovascular, and other disorders. The authors propose a close proximity hybrid system design in which a C-arm fluoroscopy unit is placed immediately adjacent to the solenoid magnet of a MR system with a minimum distance of 1.2 m between the x-ray and MR imaging fields of view. Existing rotating anode x-ray tube designs fail within MR fringe field environments because the magnetic fields alter the electron trajectories in the x-ray tube and act as a brake on the induction motor, reducing the rotation speed of the anode. In this study the authors propose a novel motor design that avoids the anode rotation speed reduction. Methods: The proposed design replaces the permanent magnet stator found in brushed dc motors with the radial component of the MR fringe field. The x-ray tube is oriented such that the radial component of the MR fringe field is orthogonal to the cathode-anode axis. Using a feedback position sensor and the support bearings as electrical slip rings, the authors use electrical commutation to eliminate the need for mechanical brushes and commutators. A vacuum compatible prototype of the proposed motor design was assembled, and its performance was evaluated at various operating conditions. The prototype consisted of a 3.1 in. diameter anode rated at 300 kHU with a ceramic rotor that was 5.6 in. in length and had a 2.9 in. diameter. The material chosen for all ceramic components was MACOR, a machineable glass ceramic developed by Corning Inc. The approximate weight of the entire assembly was 1750 g. The maximum rotation speed, angular acceleration, and acceleration time of the motor design were investigated, as well as the dependence of these parameters on rotor angular offset, magnetic field strength, and field orientation. The resonance properties of the authors' assembly were also evaluated to determine its stability during acceleration, and a pulse width modulation algorithm was implemented to control the rotation speed of the motor. Results: At a magnetic flux density of 41 mT orthogonal to the axis of rotation (on the lower end of the expected flux density in the MR suite) the maximum speed of the motor was found to be 5150 revolutions per minute (rpm). The acceleration time necessary to reach 3000 rpm was found to be approximately 10 s at 59 mT. The resonance frequency of the assembly with the anode attached was 1310 rpm (21.8 Hz) which is far below the desired operating speeds. Pulse width modulation provides an effective method to control the speed of the motor with a resolution of 100 rpm. Conclusions: The proposed design can serve as a direct replacement to the conventional induction motor used in rotating anode x-ray tubes. It does not suffer from a reduced rotation speed when operating in a MR environment. The presence of chromic steel bearings in the prototype prevented testing at the higher field strengths, and future iterations of the design could eliminate this shortcoming. The prototype assembly demonstrates proof of concept of the authors' design and overcomes one of the major obstacles for a MR compatible rotating anode x-ray tube.

Lillaney, Prasheel; Pelc, Norbert [Department of Radiology, Stanford University, Stanford, California 94305 and Department of Bioengineering, Stanford University, Stanford, California 94305 (United States); Shin Mihye [Department of Radiology, Stanford University, Stanford, California 94305 and Department of Mechanical Engineering, Stanford University, Stanford, California 94305 (United States); Hinshaw, Waldo; Fahrig, Rebecca [Department of Radiology, Stanford University, Stanford, California 94305 (United States); Bennett, N. Robert [Department of Radiology, Stanford University, Stanford, California 94305 and Qualcomm MEMS Technologies, San Jose, California 95134 (United States)

2013-02-15T23:59:59.000Z

112

Magnetic Devices and Nanostructures (2007)  

Science Conference Proceedings (OSTI)

... a form of transmission electron microscopy (TEM) that uses the defection of electrons as they ... Magnetic force microscope image of 100-nanometer ...

2010-10-05T23:59:59.000Z

113

Nuclear magnetic resonance contrast agents  

DOE Patents (OSTI)

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.

Smith, Paul H. (Los Alamos, NM); Brainard, James R. (Los Alamos, NM); Jarvinen, Gordon D. (Los Alamos, NM); Ryan, Robert R. (Los Alamos, NM)

1997-01-01T23:59:59.000Z

114

Nuclear magnetic resonance contrast agents  

DOE Patents (OSTI)

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.

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

1997-12-30T23:59:59.000Z

115

Urinary Tract Effects After Multifocal Nonthermal Irreversible Electroporation of the Kidney: Acute and Chronic Monitoring by Magnetic Resonance Imaging, Intravenous Urography and Urinary Cytology  

Science Conference Proceedings (OSTI)

Purpose: The nonthermal irreversible electroporation (NTIRE) is a novel potential ablation modality for renal masses. The aim of this study was the first evaluation of NTIRE's effects on the renal urine-collecting system using intravenous urography (IVU) and urinary cytology in addition to histology and magnetic resonance imaging (MRI). Methods: Eight percutaneous NTIRE ablations of the renal parenchyma, including the calyxes or pelvis, were performed in three male swine. MRI, IVU, histology, and urinary cytology follow-ups were performed within the first 28 days after treatment. Results: MRI and histological analysis demonstrated a localized necrosis 7 days and a localized scarification of the renal parenchyma with complete destruction 28 days after NTIRE. The urine-collecting system was preserved and showed urothelial regeneration. IVU and MRI showed an unaltered normal morphology of the renal calyxes, pelvis, and ureter. A new urinary cytology phenomenon featured a temporary degeneration by individual vacuolization of detached transitional epithelium cells within the first 3 days after NTIRE. Conclusions: This first urographical, urine-cytological, and MRI evaluation after porcine kidney NTIRE shows multifocal parenchyma destruction while protecting the involved urine-collecting system with regenerated urothelial tissue. NTIRE could be used as a targeted ablation method of centrally located renal masses.

Wendler, Johann Jakob, E-mail: johann.wendler@med.ovgu.de [University of Magdeburg, Department of Urology (Germany); Pech, Maciej [University of Magdeburg, Department of Radiology and Nuclear Medicine (Germany); Porsch, Markus; Janitzky, Andreas [University of Magdeburg, Department of Urology (Germany); Fischbach, Frank [University of Magdeburg, Department of Radiology and Nuclear Medicine (Germany); Buhtz, Peter; Vogler, Klaus [University of Magdeburg, Institute of Pathology (Germany); Huehne, Sarah [University of Magdeburg, Department of Urology (Germany); Borucki, Katrin [University of Magdeburg, Institute of Clinical Chemistry (Germany); Strang, Christof [University of Magdeburg, Department of Anaesthesiology (Germany); Mahnkopf, Dirk [Institute of Medical Technology and Research (Germany); Ricke, Jens [University of Magdeburg, Department of Radiology and Nuclear Medicine (Germany); Liehr, Uwe-Bernd [University of Magdeburg, Department of Urology (Germany)

2012-08-15T23:59:59.000Z

116

Role of Diffusion-Weighted Magnetic Resonance Imaging in Predicting Sensitivity to Chemoradiotherapy in Muscle-Invasive Bladder Cancer  

Science Conference Proceedings (OSTI)

Purpose: In chemoradiation (CRT)-based bladder-sparing approaches for muscle invasive bladder cancer (MIBC), patients who respond favorably to induction CRT enjoy the benefits of bladder preservation, whereas nonresponders do not. Thus, accurate prediction of CRT sensitivity would optimize patient selection for bladder-sparing protocols. Diffusion-weighted MRI (DW-MRI) is a functional imaging technique that quantifies the diffusion of water molecules in a noninvasive manner. We investigated whether DW-MRI predicts CRT sensitivity of MIBC. Methods and Materials: The study cohort consisted of 23 MIBC patients (cT2/T3 = 7/16) who underwent induction CRT consisting of radiotherapy to the small pelvis (40 Gy) with two cycles of cisplatin (20 mg/day for 5 days), followed by partial or radical cystectomy. All patients underwent DW-MRI before the initiation of treatment. Associations of apparent diffusion coefficient (ADC) values with CRT sensitivity were analyzed. The proliferative potential of MIBC was also assessed by analyzing the Ki-67 labeling index (LI) in pretherapeutic biopsy specimens. Results: Thirteen patients (57%) achieved pathologic complete response (pCR) to CRT. These CRT-sensitive MIBCs showed significantly lower ADC values (median, 0.63 Multiplication-Sign 10{sup -3} mm{sup 2}/s; range, 0.43-0.77) than CRT-resistant (no pCR) MIBCs (median, 0.84 Multiplication-Sign 10{sup -3} mm{sup 2}/s; range, 0.69-1.09; p = 0.0003). Multivariate analysis identified ADC value as the only significant and independent predictor of CRT sensitivity (p < 0.0001; odds ratio per 0.001 Multiplication-Sign 10{sup -3} mm{sup 2}/s increase, 1.03; 95% confidence interval, 1.01-1.08). With a cutoff ADC value at 0.74 Multiplication-Sign 10{sup -3} mm{sup 2}/s, sensitivity/specificity/accuracy in predicting CRT sensitivity was 92/90/91%. Ki-67 LI was significantly higher in CRT-sensitive MIBCs (p = 0.0005) and significantly and inversely correlated with ADC values ({rho} = -0.67, p = 0.0007). Conclusions: DW-MRI is a potential biomarker for predicting CRT sensitivity in MIBC. DW-MRI may be useful to optimize patient selection for CRT-based bladder-sparing approaches.

Yoshida, Soichiro [Department of Urology, Tokyo Medical and Dental University Graduate School, Tokyo (Japan); Koga, Fumitaka, E-mail: f-koga.uro@tmd.ac.jp [Department of Urology, Tokyo Medical and Dental University Graduate School, Tokyo (Japan); Kobayashi, Shuichiro [Department of Urology, Tokyo Medical and Dental University Graduate School, Tokyo (Japan); Ishii, Chikako; Tanaka, Hiroshi [Department of Radiology, Ochanomizu Surugadai Clinic, Tokyo (Japan); Tanaka, Hajime; Komai, Yoshinobu; Saito, Kazutaka; Masuda, Hitoshi; Fujii, Yasuhisa; Kawakami, Satoru; Kihara, Kazunori [Department of Urology, Tokyo Medical and Dental University Graduate School, Tokyo (Japan)

2012-05-01T23:59:59.000Z

117

Magnetized and collimated millimeter scale plasma jets with astrophysical relevance  

Science Conference Proceedings (OSTI)

Magnetized collimated plasma jets are created in the laboratory to extend our understanding of plasma jet acceleration and collimation mechanisms with particular connection to astrophysical jets. In this study, plasma collimated jets are formed from supersonic unmagnetized flows, mimicking a stellar wind, subject to currents and magnetohydrodynamic forces. It is found that an external poloidal magnetic field, like the ones found anchored to accretion disks, is essential to stabilize the jets against current-driven instabilities. The maximum jet length before instabilities develop is proportional to the field strength and the length threshold agrees well with Kruskal-Shafranov theory. The plasma evolution is modeled qualitatively using MHD theory of current-carrying flux tubes showing that jet acceleration and collimation arise as a result of electromagnetic forces.

Brady, Parrish C.; Quevedo, Hernan J. [Texas Center for High Intensity Laser Science, University of Texas at Austin, Austin, Texas 78712 (United States); Valanju, Prashant M. [Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712-1060 (United States); Bengtson, Roger D.; Ditmire, Todd [Department of Physics, University of Texas at Austin, Austin, Texas 78712 (United States)

2012-01-15T23:59:59.000Z

118

In Vivo Near-Infrared Spectroscopy and Magnetic Resonance Imaging Monitoring of Tumor Response to Combretastatin A-4-Phosphate Correlated With Therapeutic Outcome  

Science Conference Proceedings (OSTI)

Purpose: To develop a combination treatment consisting of combretastatin A-4-phosphate (CA4P) with radiation based on tumor oxygenation status. Methods and Materials: In vivo near-infrared spectroscopy (NIRS) and diffusion-weighted (DW) magnetic resonance imaging (MRI) were applied to noninvasively monitor changes in tumor blood oxygenation and necrosis induced by CA4P (30 mg/kg) in rat mammary 13762NF adenocarcinoma, and the evidence was used to optimize combinations of CA4P and radiation treatment (a single dose of 5 Gy). Results: NIRS showed decreasing concentrations of tumor vascular oxyhemoglobin and total hemoglobin during the first 2 h after CA4P treatment, indicating significant reductions in tumor blood oxygenation and perfusion levels (p < 0.001). Twenty-four hours later, in response to oxygen inhalation, significant recovery was observed in tumor vascular and tissue oxygenation according to NIRS and pimonidazole staining results, respectively (p < 0.05). DW MRI revealed significantly increased water diffusion in tumors measured by apparent diffusion coefficient at 24 h (p < 0.05), suggesting that CA4P-induced central necrosis. In concordance with the observed tumor oxygen dynamics, we found that treatment efficacy depended on the timing of the combined therapy. The most significant delay in tumor growth was seen in the group of tumors treated with radiation while the rats breathed oxygen 24 h after CA4P administration. Conclusions: Noninvasive evaluation of tumor oxygen dynamics allowed us to rationally enhance the response of syngeneic rat breast tumors to combined treatment of CA4P with radiation.

Zhao Dawen, E-mail: Dawen.Zhao@UTSouthwestern.ed [Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Chang Chenghui [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Kim, Jae G.; Liu Hanli [Joint Program in Biomedical Engineering, University of Texas Arlington and University of Texas Southwestern Medical Center, Arlington, Texas (United States); Mason, Ralph P. [Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Joint Program in Biomedical Engineering, University of Texas Arlington and University of Texas Southwestern Medical Center, Arlington, Texas (United States)

2011-06-01T23:59:59.000Z

119

Value of Diffusion-Weighted Magnetic Resonance Imaging for Prediction and Early Assessment of Response to Neoadjuvant Radiochemotherapy in Rectal Cancer: Preliminary Results  

Science Conference Proceedings (OSTI)

Purpose: To evaluate diffusion-weighted magnetic resonance imaging (DWI) for response prediction before and response assessment during and early after preoperative radiochemotherapy (RCT) for locally advanced rectal cancer (LARC). Methods and Materials: Twenty patients receiving RCT for LARC underwent MRI including DWI before RCT, after 10-15 fractions and 1 to 2 weeks before surgery. Tumor volume and apparent diffusion coefficient (ADC; b-values: 0-1000 s/mm{sup 2}) were determined at all time points. Pretreatment tumor ADC and volume, tumor ADC change ( Increment ADC), and volume change ( Increment V) between pretreatment and follow-up examinations were compared with histopathologic findings after total mesorectal excision (pathologic complete response [pCR] vs. no pCR, ypT0-2 vs. ypT3-4, T-downstaging or not). The discriminatory capability of pretreatment tumor ADC and volume, Increment ADC, and Increment V for the detection of pCR was compared with receiver operating characteristics analysis. Results: Pretreatment ADC was significantly lower in patients with pCR compared with patients without (in mm{sup 2}/s: 0.94 {+-} 0.12 Multiplication-Sign 10{sup -3} vs. 1.19 {+-} 0.22 Multiplication-Sign 10{sup -3}, p = 0.003), yielding a sensitivity of 100% and specificity of 86% for detection of pCR. The volume reduction during and after RCT was significantly higher in patients with pCR compared with patients without (in %: {Delta}V{sub during}: -62 {+-} 16 vs. -33 {+-} 16, respectively, p = 0.015; and {Delta}V{sub post}: -86 {+-} 12 vs. -60 {+-} 21, p = 0.012), yielding a sensitivity of 83% and specificity of 71% for the {Delta}V{sub during} and, respectively, 83% and 86% for the {Delta}V{sub post}. The Increment ADC during ({Delta}ADC{sub during}) and after RCT ({Delta}ADC{sub post}) showed a significantly higher value in patients with pCR compared with patients without (in %: {Delta}ADC{sub during}: 72 {+-} 14 vs. 16 {+-} 12, p = 0.0006; and {Delta}ADC{sub post}: 88 {+-} 35 vs. 26 {+-} 19, p = 0.0011), yielding a sensitivity and specificity of 100% for the {Delta}ADC{sub during} and, respectively, 100% and 93% for the {Delta}ADC{sub post}. Conclusions: These initial findings indicate that DWI, using pretreatment ADC, {Delta}ADC{sub during}, and {Delta}ADC{sub post} may be useful for prediction and early assessment of pathologic response to preoperative RCT of LARC, with higher accuracy than volumetric measurements.

Lambrecht, Maarten, E-mail: maarten.lambrecht@uzleuven.be [Department of Radiation Oncology, UZ Gasthuisberg, Leuven (Belgium); Vandecaveye, Vincent; De Keyzer, Frederik [Department of Radiology, UZ Gasthuisberg, Leuven (Belgium); Roels, Sarah [Department of Radiation Oncology, UZ Gasthuisberg, Leuven (Belgium); Penninckx, Freddy [Department of Abdominal Surgery, UZ Gasthuisberg, Leuven (Belgium); Van Cutsem, Eric [Department of Digestive Oncology, UZ Gasthuisberg, Leuven (Belgium); Filip, Claus [Department of Radiology, UZ Gasthuisberg, Leuven (Belgium); Haustermans, Karin [Department of Radiation Oncology, UZ Gasthuisberg, Leuven (Belgium)

2012-02-01T23:59:59.000Z

120

Superconducting Magnet Division | Brookhaven National Laboratory  

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

accuracy of these probes is 1 part in 10,000 at 23 of the magnet inner radius. Hall and NMR probes are also available. generic image The photo shows a magnet cold mass being...

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


121

ON THE STRUCTURE AND STABILITY OF MAGNETIC TOWER JETS  

SciTech Connect

Modern theoretical models of astrophysical jets combine accretion, rotation, and magnetic fields to launch and collimate supersonic flows from a central source. Near the source, magnetic field strengths must be large enough to collimate the jet requiring that the Poynting flux exceeds the kinetic energy flux. The extent to which the Poynting flux dominates kinetic energy flux at large distances from the engine distinguishes two classes of models. In magneto-centrifugal launch models, magnetic fields dominate only at scales {approx}< 100 engine radii, after which the jets become hydrodynamically dominated (HD). By contrast, in Poynting flux dominated (PFD) magnetic tower models, the field dominates even out to much larger scales. To compare the large distance propagation differences of these two paradigms, we perform three-dimensional ideal magnetohydrodynamic adaptive mesh refinement simulations of both HD and PFD stellar jets formed via the same energy flux. We also compare how thermal energy losses and rotation of the jet base affects the stability in these jets. For the conditions described, we show that PFD and HD exhibit observationally distinguishable features: PFD jets are lighter, slower, and less stable than HD jets. Unlike HD jets, PFD jets develop current-driven instabilities that are exacerbated as cooling and rotation increase, resulting in jets that are clumpier than those in the HD limit. Our PFD jet simulations also resemble the magnetic towers that have been recently created in laboratory astrophysical jet experiments.

Huarte-Espinosa, M.; Frank, A.; Blackman, E. G. [Department of Physics and Astronomy, University of Rochester, 600 Wilson Boulevard, Rochester, NY 14627-0171 (United States); Ciardi, A. [LERMA, Universite Pierre et Marie Curie, Observatoire de Paris, F-92195 Meudon (France); Hartigan, P. [Department of Physics and Astronomy, Rice University, 6100 S. Main, Houston, TX 77521-1892 (United States); Lebedev, S. V.; Chittenden, J. P. [Blackett Laboratory, Imperial College London, SW7 2BW London (United Kingdom)

2012-09-20T23:59:59.000Z

122

Excitation and readout Designs for high field spectroscopic imaging  

E-Print Network (OSTI)

In this thesis we state and demonstrate solutions to three engineering problems that arise in magnetic resonance imaging RF excitation with parallel transmission (pTx) and magnetic resonance spectroscopic imaging (MRSI). ...

Lee, Joonsung

2011-01-01T23:59:59.000Z

123

Edge structure preserving 3-D image denoising  

Science Conference Proceedings (OSTI)

In various applications, including magnetic resonance imaging (MRI) and functional MRI (fMRI), 3- D images get increasingly popular. To improve reliability of subsequent image analyses, 3-D image denoising is often a necessary pre-processing step, which ... Keywords: edge-preserving image restoration, jump regression analysis, surface estimation

Peihua Qiu; Partha Sarathi Mukherjee

2011-01-01T23:59:59.000Z

124

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Image Gallery : Image Details. 72 DPI Image 150 DPI Image No 300 DPI Version. Title: Frequency Comb, Ultrafast Laser. ...

125

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Image Gallery : Image Details. 72 DPI Image 150 DPI Image No 300 DPI Version. Title: Iron-Based Superconductors. Description ...

126

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Image Gallery : Image Details. 72 DPI Image 150 DPI Image No 300 DPI Version. Title: Space Weather Forecasts. Description ...

127

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Image Gallery : Image Details. 72 DPI Image 150 DPI Image No 300 DPI Version. Title: Organic Solar Power. Description ...

128

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image 150 DPI Image 300 DPI Image . Title: Nanotechnology; Biotechnology/Health; Nanocrystals; Hwang. ...

129

A linear helicon plasma device with controllable magnetic field gradient  

Science Conference Proceedings (OSTI)

Current free double layers (CFDLs) are localized potential structures having spatial dimensions - Debye lengths and potential drops of more than local electron temperature across them. CFDLs do not need a current for them to be sustained and hence they differ from the current driven double layers. Helicon antenna produced plasmas in an expanded chamber along with an expanding magnetic field have shown the existence of CFDL near the expansion region. A helicon plasma device has been designed, fabricated, and installed in the Institute for Plasma Research, India to study the role of maximum magnetic field gradient as well as its location with respect to the geometrical expansion region of the chamber in CFDL formation. The special feature of this machine consisting of two chambers of different radii is its capability of producing different magnetic field gradients near the physical boundary between the two chambers either by changing current in one particular coil in the direction opposite to that in other coils and/or by varying the position of this particular coil. Although, the machine is primarily designed for CFDL experiments, it is also capable of carrying out many basic plasma physics experiments such as wave propagation, wave coupling, and plasma instabilities in a varying magnetic field topology. In this paper, we will present the details of the machine construction, its specialties, and some preliminary results about the production and characterization of helicon plasma in this machine.

Barada, Kshitish K.; Chattopadhyay, P. K.; Ghosh, J.; Kumar, Sunil; Saxena, Y. C. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India)

2012-06-15T23:59:59.000Z

130

Superconducting Magnets  

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

magnet technology has allowed physicists to attain higher energies in circular accelerators. One can obtain higher magnetic fields because there is no resistance in a...

131

User Science Images  

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

User Science Images User Science Images User Science Images Sort by: Default | Name | Date (low-high) | Date (high-low) | Category NIMROD-1.png FES: NIMROD Simulation February 18, 2010 | Author(s): Dr. Charlson C. Kim (University of Washington) | Category: Fusion Energy | URL: https://nimrodteam.org/ Download Image: NIMROD-1.png | png | 1.5 MB Trajectory of an energetic ion in a Field Reverse Configuration (FRC) magnetic field. Magnetic separatrix denoted by green surface. Spheres are colored by azimuthal velocity. Image courtesy of Charlson Kim, University of Washington; NERSC repos m487, mp21, m1552 Scheibe.png BER: Pore-Scale Fluid Flow for Subsurface Reactive Transport January 1, 2008 | Author(s): Timothy D. Scheibe, PNNL | Category: Environmental Science | URL: http://http://subsurface.pnl.gov/

132

Fourier Transform Near Infrared Microspectroscopy, Infrared Chemical Imaging, High-Resolution Nuclear Magnetic Resonance and Fluorescence Microspectroscopy Detection of Single Cancer Cells and Single Viral Particles  

E-Print Network (OSTI)

Single Cancer Cells from Human tumors are being detected and imaged by Fourier Transform Infrared (FT-IR), Fourier Transform Near Infrared (FT-NIR)Hyperspectral Imaging and Fluorescence Correlation Microspectroscopy. The first FT-NIR chemical, microscopic images of biological systems approaching one micron resolution are here reported. Chemical images obtained by FT-NIR and FT-IR Microspectroscopy are also presented for oil in soybean seeds and somatic embryos under physiological conditions. FT-NIR spectra of oil and proteins were obtained for volumes as small as two cubic microns. Related, HR-NMR analyses of oil contents in somatic embryos as well as 99% accurate calibrations are also presented here with nanoliter precision. Such high-resolution, 400 MHz H-1 NMR analyses allowed the selection of mutagenized embryos with higher oil content (e.g. >~20%) compared to the average levels in non-mutagenized control embryos. Moreover, developmental changes in single soybean seeds and/or somatic embryos may be monito...

Baianu,I C; Hofmann, N E; Korban, S S; Lozano, P; You, T

2004-01-01T23:59:59.000Z

133

Frontiers in Chemical Imaging Seminar Series  

E-Print Network (OSTI)

Frontiers in Chemical Imaging Seminar Series X-ray Imaging at the Nanoscale Presented by Ian Mc and exquisite sensitivity to elemental, chemical and magnetic states in buried structures. The advent

134

COLLIMATION AND CONFINEMENT OF MAGNETIC JETS BY EXTERNAL MEDIA  

Science Conference Proceedings (OSTI)

We study the collimation of a highly magnetized jet by a surrounding cocoon that forms as a result of the interaction of the jet with the external medium. We show that in regions where the jet is well confined by the cocoon, current-driven instabilities should develop over timescales shorter than the expansion time of the jet's head. We speculate that these instabilities would give rise to complete magnetic field destruction, whereby the jet undergoes a transition from high to low sigma above the collimation zone. Using this assumption, we construct a self-consistent model for the evolution of the jet-cocoon system in an ambient medium of arbitrary density profile. We apply the model to jet breakout in long gamma-ray bursts (GRBs) and show that the jet is highly collimated inside the envelope of the progenitor star and is likely to remain confined well after breakout. We speculate that this strong confinement may provide a channel for magnetic field conversion in GRB outflows, whereby the hot, low-sigma jet section thereby produced is the source of the photospheric emission observed in many bursts.

Levinson, Amir [School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978 (Israel)] [School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978 (Israel); Begelman, Mitchell C., E-mail: Levinson@wise.tau.ac.il, E-mail: mitch@jila.colorado.edu [JILA, University of Colorado and National Institute of Standards and Technology, 440 UCB, Boulder, CO 80309-0440 (United States)

2013-02-20T23:59:59.000Z

135

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image 150 DPI Image 300 DPI Image . Title: Quantum Physics; Quantum Communications; Ultrafast Photon Detector; Nam. ...

136

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image 150 DPI Image 300 DPI Image . Title: Scanning Electron Microscope with Spin Polarization Analysis. ...

137

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image 150 DPI Image 300 DPI Image . Title: Metrology, Basic Units; Mass; Electronic Kilogram. Description ...

138

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image 150 DPI Image 300 DPI Image . Title: Energy; Fossil Fuels;Distillation Curves for Complex Fuel Mixtures. ...

139

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... nist.gov. 72 DPI Image 150 DPI Image 300 DPI Image . Title: Public safety & Smart Grid. Description: Electrical engineer ...

140

Methods for functional brain imaging  

E-Print Network (OSTI)

Magnetic resonance imaging (MRI) has demonstrated the potential for non-invasive mapping of structure and function (fMRI) in the human brain. In this thesis, we propose a series of methodological developments towards ...

Witzel, Thomas, Ph. D. Massachusetts Institute of Technology

2011-01-01T23:59:59.000Z

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


141

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Image Gallery : Image Details. 72 DPI Image No 150 DPI Version 300 DPI Image. Title: Ultrafast Laser Speeds Up Quest for Atomic Control. ...

142

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image 150 DPI Image 300 DPI Image . Title: New Imaging Tool is Boon to Fuel Cell Research. Description: NIST ...

143

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Image Gallery : Image Details. 72 DPI Image 150 DPI Image No 300 DPI Version. Title: House; Trees. Description: *BFRL. Subjects (names): ...

144

Correlated magnetic reversal in periodic stripe patterns  

Science Conference Proceedings (OSTI)

The magnetization reversal in a periodic magnetic stripe array has been studied with a combination of direct and reciprocal space methods: Kerr microscopy and polarized neutron scattering. Kerr images show that during magnetization reversal over a considerable magnetic-field range a ripple domain state occurs in the stripes with magnetization components perpendicular to the stripes. Quantitative analysis of polarized neutron specular reflection, Bragg diffraction, and off-specular diffuse scattering provides a detailed picture of the mean magnetization direction in the ripple domains as well as longitudinal and transverse fluctuations, and reveals a strong correlation of those components over a number of stripes.

Theis-Broehl, Katharina; Toperverg, Boris P.; Leiner, Vincent; Westphalen, Andreas; Zabel, Hartmut; McCord, Jeffrey; Rott, Karsten; Brueckl, Hubert [Department of Physics, Ruhr-University Bochum, 44780 Bochum (Germany); Leibniz Institute for Solid State and Materials Research Dresden, Institute for Metallic Materials, Helmholtzstr. 20, D-01169 Dresden (Germany); Department of Physics, University Bielefeld, Universitaetsstr. 25, 33615 Bielefeld (Germany)

2005-01-01T23:59:59.000Z

145

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... known as 'antiferromagnetic coupling,' in which manganese (Mn) atoms in successive magnetic layers spontaneously orient their magnetization in ...

146

Using X-ray mammograms to assist in microwave breast image interpretation  

Science Conference Proceedings (OSTI)

Current clinical breast imaging modalities include ultrasound, magnetic resonance (MR) imaging, and the ubiquitous X-ray mammography. Microwave imaging, which takes advantage of differing electromagnetic properties to obtain image contrast, shows potential ...

Charlotte Curtis; Richard Frayne; Elise Fear

2012-01-01T23:59:59.000Z

147

Plenary lecture 2: local surface approximation for edge structure preserving 3-D image denoising  

Science Conference Proceedings (OSTI)

In various applications, including magnetic resonance imaging (MRI) and functional MRI (fMRI), 3-D images get increasingly popular. To improve reliability of subsequent image analyses, 3-D image denoising is often a necessary pre-processing step, which ...

Peihua Qiu

2011-01-01T23:59:59.000Z

148

Video Toroid Cavity Imager  

DOE Patents (OSTI)

A video toroid cavity imager for in situ measurement of electrochemical properties of an electrolytic material sample includes a cylindrical toroid cavity resonator containing the sample and employs NMR and video imaging for providing high-resolution spectral and visual information of molecular characteristics of the sample on a real-time basis. A large magnetic field is applied to the sample under controlled temperature and pressure conditions to simultaneously provide NMR spectroscopy and video imaging capabilities for investigating electrochemical transformations of materials or the evolution of long-range molecular aggregation during cooling of hydrocarbon melts. The video toroid cavity imager includes a miniature commercial video camera with an adjustable lens, a modified compression coin cell imager with a fiat circular principal detector element, and a sample mounted on a transparent circular glass disk, and provides NMR information as well as a video image of a sample, such as a polymer film, with micrometer resolution.

Gerald, Rex E. II; Sanchez, Jairo; Rathke, Jerome W.

2004-08-10T23:59:59.000Z

149

Near Infrared Microspectroscopy, Fluorescence Microspectroscopy, Infrared Chemical Imaging and High Resolution Nuclear Magnetic Resonance Analysis of Soybean Seeds, Somatic Embryos and Single Cells  

E-Print Network (OSTI)

Novel methodologies are currently being developed and established for the chemical analysis of soybean seeds, embryos and single cells by Fourier Transform Infrared (FT-IR), Fourier Transform Near Infrared (FT-NIR) Microspectroscopy, Fluorescence and High-Resolution NMR (HR-NMR). The first FT-NIR chemical images of biological systems approaching one micron resolution are presented here. Chemical images obtained by FT-NIR and FT-IR Microspectroscopy are presented for oil in soybean seeds and somatic embryos under physiological conditions. FT-NIR spectra of oil and proteins were obtained for volumes as small as two cubic microns. Related, HR-NMR analyses of oil contents in somatic embryos are also presented here with nanoliter precision. Such 400 MHz 1H NMR analyses allowed the selection of mutagenized embryos with higher oil content (e.g. ~20%) compared to non-mutagenized control embryos. Moreover, developmental changes in single soybean seeds and/or somatic embryos may be monitored by FT-NIR with a precision ...

Baianu, I C; Hofmann, N E; Korban, S S; Lozano, P; You, T; AOCS 94th Meeting, Kansas

2002-01-01T23:59:59.000Z

150

Magnetic Storms  

Science Conference Proceedings (OSTI)

... magnetic reversal. As there is no predictive science of geomagnetism, we currently lack even simple forecasts. Our scientific ...

2010-10-05T23:59:59.000Z

151

Magnetic Properties  

Science Conference Proceedings (OSTI)

...Since the discovery of high-temperature superconductors in 1986 (Ref 10), the demonstration of magnetic flux exclusion

152

A DUAL MODALITY SYSTEM FOR HIGH RESOLUTION -TRUE CONDUCTIVITY IMAGING  

E-Print Network (OSTI)

the difference between the current densities calculated based on the potential and the magnetic field Resonance Current Density Imaging (MRCDI) has been proposed to image current density and magnetic flux the current density at dc and RF frequency (Scoot et al 1995). Using MRCDI, the magnetic flux density

Eyüboðlu, Murat

153

Taking the Stress Out of Magnetic Field Detection  

Science Conference Proceedings (OSTI)

... Transmission electron microscope (TEM) images show sections of a continuous 400 ... that draw in external magnetic field lines and concentrate them ...

2012-10-18T23:59:59.000Z

154

High Field Magnetic Resonance Facility  

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

HFMRF Overview HFMRF Overview Section 2-3-1 High Field Magnetic Resonance Facility The High Field Magnetic Resonance Facility (HFMRF) focuses a significant portion of its research on developing a fundamental, molecular-level understanding of biochemical and biological systems and their response to environmental effects. A secondary focus is materials science, including catalysis and chemical mechanisms and processes. Staff and science consultants within this facility offer expertise in the areas of structural biology, solid-state materials characterization, and magnetic resonance imaging (MRI) techniques. Research activities in the HFMRF include: * structure determination of large molecular assemblies such as protein-DNA (normal and damaged DNA) and protein-RNA complexes

155

Large Magnetization at Carbon Surfaces  

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

Large Magnetization at Carbon 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 scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided valuable insight into how proton irradiation can cause carbon to transform into a ferromagnetic material. 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 hydrogen (i.e. protons) on the electronic structure of carbon. In studying the properties of electrons responsible for magnetic order in graphite, researchers found that a very large magnetic moment is essentially switched on when hydrogen atoms are incorporated at the surface of graphite.

156

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image 150 DPI Image 300 DPI Image . Title: Homeland Security; Chem., Bio, and Other Threats; Standards for Radiation Detection. ...

157

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image 150 DPI Image 300 DPI Image . Title: Iron-based and Copper-Oxide High-Temperature Superconductors. ...

158

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Image Gallery : Image Details. No 72 DPI Version No 150 DPI Version 300 DPI Image. Title: Gold Nano Anchors Put Nanowires in Their Place. ...

159

Magnetic Barcoded Hydrogel Microparticles for Multiplexed Detection  

E-Print Network (OSTI)

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

Bong, Ki Wan

160

Magnetic Materials  

Science Conference Proceedings (OSTI)

Oct 27, 2009 ... Extreme magnetic fields (>2 tesla), especially when combined with temperature, are being shown to revolutionize materials processing and...

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


161

Magnetic nanotubes  

DOE Patents (OSTI)

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.

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

2010-11-16T23:59:59.000Z

162

Superconducting Magnets  

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

Mit Hilfe der Technologie supraleitender Magnete lassen sich in Mit Hilfe der Technologie supraleitender Magnete lassen sich in Ringbeschleunigern höhere Energien erreichen. Weil supraleitende Spulen keinen elektrischen Widerstand aufweisen, können damit stärkere Magnetfelder erzeugt werden. In normal leitenden Elektromagneten wird - wegen des elektrischen Widerstands der Drähte - die Spule aufgeheizt. Auf diese Weise geht sehr viel Energie in Form von Wärme verloren, was die Energiekosten dieser Magnete in die Höhe treibt. Supraleitende Spulen erlauben es, Magnete grosser Feldstärke unter günstigen Bedingungen zu betreiben und damit die Energiekosten zu senken. Durch den Einbau supraleitender Spulen in den Ringbeschleuniger von Fermilab konnte dessen Energie verdoppelt werden.Auch der im Bau befindliche "Large Hadron Collider" am CERN wird supraleitende Magnete

163

Superconductive imaging surface magnetometer  

DOE Patents (OSTI)

An improved pick-up coil system for use with Superconducting Quantum Interference Device gradiometers and magnetometers involving the use of superconducting plates near conventional pick-up coil arrangements to provide imaging of nearby dipole sources and to deflect environmental magnetic noise away from the pick-up coils. This allows the practice of gradiometry and magnetometry in magnetically unshielded environments. One embodiment uses a hemispherically shaped superconducting plate with interior pick-up coils, allowing brain wave measurements to be made on human patients. another embodiment using flat superconducting plates could be used in non-destructive evaluation of materials.

Overton, Jr., William C. (Los Alamos, NM); van Hulsteyn, David B. (Santa Fe, NM); Flynn, Edward R. (Los Alamos, NM)

1991-01-01T23:59:59.000Z

164

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Title: Nanoscale Blasting Adjusts Resistance in Magnetic Sensors. Description: Cartoon illustrates new NIST technique ...

165

Large Magnetization at Carbon Surfaces  

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

Large Magnetization at Carbon Surfaces Print 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 valuable insight into how proton irradiation can cause carbon to transform into a ferromagnetic material. 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 hydrogen (i.e. protons) on the electronic structure of carbon. In studying the properties of electrons responsible for magnetic order in graphite, researchers found that a very large magnetic moment is essentially switched on when hydrogen atoms are incorporated at the surface of graphite.

166

Large Magnetization at Carbon Surfaces  

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

Large Magnetization at Carbon Surfaces Print 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 valuable insight into how proton irradiation can cause carbon to transform into a ferromagnetic material. 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 hydrogen (i.e. protons) on the electronic structure of carbon. In studying the properties of electrons responsible for magnetic order in graphite, researchers found that a very large magnetic moment is essentially switched on when hydrogen atoms are incorporated at the surface of graphite.

167

Large Magnetization at Carbon Surfaces  

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

Large Magnetization at Carbon Surfaces Print 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 valuable insight into how proton irradiation can cause carbon to transform into a ferromagnetic material. 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 hydrogen (i.e. protons) on the electronic structure of carbon. In studying the properties of electrons responsible for magnetic order in graphite, researchers found that a very large magnetic moment is essentially switched on when hydrogen atoms are incorporated at the surface of graphite.

168

Large Magnetization at Carbon Surfaces  

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

Large Magnetization at Carbon Surfaces Print 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 valuable insight into how proton irradiation can cause carbon to transform into a ferromagnetic material. 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 hydrogen (i.e. protons) on the electronic structure of carbon. In studying the properties of electrons responsible for magnetic order in graphite, researchers found that a very large magnetic moment is essentially switched on when hydrogen atoms are incorporated at the surface of graphite.

169

Nuclear Magnetic Resonance Laboratory  

Science Conference Proceedings (OSTI)

Nuclear Magnetic Resonance Laboratory. ... A 600 MHz Nuclear Magnetic Resonance Spectrometer. Analytical Data Compilation Reference Materials. ...

2012-10-01T23:59:59.000Z

170

Quantitative susceptibility mapping and susceptibility-based distortion correction of echo planar images  

E-Print Network (OSTI)

The field of medical image analysis continues to expand as magnetic resonance imaging (MRI) technology advances through increases in field strength and the development of new image acquisition and reconstruction methods. ...

Poynton, Clare (Clare Brenna)

2012-01-01T23:59:59.000Z

171

Learning About Magnets!  

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

the the National High Magnetic Field Laboratory Learning About Name A magnet is a material or object that creates a magnetic fi eld. This fi eld is invisible, but it creates a force that can "attract" or "repel" other magnets and magnetic materials, like iron or nickel. What is a Magnet? This bar magnet is a permanent magnet. Permanent magnets can be found in the Earth as rocks and metals. Magnets have

172

Polarization transfer NMR imaging  

DOE Patents (OSTI)

A nuclear magnetic resonance (NMR) image is obtained with spatial information modulated by chemical information. The modulation is obtained through polarization transfer from a first element representing the desired chemical, or functional, information, which is covalently bonded and spin-spin coupled with a second element effective to provide the imaging data. First and second rf pulses are provided at first and second frequencies for exciting the imaging and functional elements, with imaging gradients applied therebetween to spatially separate the nuclei response for imaging. The second rf pulse is applied at a time after the first pulse which is the inverse of the spin coupling constant to select the transfer element nuclei which are spin coupled to the functional element nuclei for imaging. In a particular application, compounds such as glucose, lactate, or lactose, can be labeled with .sup.13 C and metabolic processes involving the compounds can be imaged with the sensitivity of .sup.1 H and the selectivity of .sup.13 C.

Sillerud, Laurel O. (Los Alamos, NM); van Hulsteyn, David B. (Santa Fe, NM)

1990-01-01T23:59:59.000Z

173

ARTIFACTS IN MAGNETIC RESONANCE IMAGING FROM ...  

Science Conference Proceedings (OSTI)

... We surmise that the symmetric susceptibility artifact is ... It has two components, the first handling material ... the positive z-axis, the z-component of the ...

174

Direct Imaging of Antiferromagnetic Vortex States  

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

unique properties for the AFM vortex state. Recently, a research team from Berkeley, Korea, and China has taken the first direct image of an AFM vortex in multilayered magnetic...

175

Neutrino magnetic moment in a magnetized plasma  

E-Print Network (OSTI)

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

N. V. Mikheev; E. N. Narynskaya

2010-11-08T23:59:59.000Z

176

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image 150 DPI Image No 300 DPI Version. Title: NIST Finds that Ethanol-Loving Bacteria Accelerate Cracking of Pipeline Steels. ...

177

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Title: Nano-Signals Get a Boost from Magnetic Spin Waves. Description: This simulation shows how two nano-oscillators ...

178

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Simultaneously applying a magnetic field causes electrons (ball) to organize in circular orbits, like a dog chasing its tail. ...

179

Magnetization Characterization Laboratory  

Science Conference Proceedings (OSTI)

... use of magnetic materials for motors, generators, transformers ... all depend on the specific magnetic characteristics of ... For example, a magnet used in ...

2012-10-23T23:59:59.000Z

180

SUPERCONDUCTING MAGNETIC ENERGY STORAGE  

E-Print Network (OSTI)

Scale Superconducting Magnetic Energy Storage Plant", IEEEfor SlIperconducting Magnetic Energy Storage Unit", inSuperconducting Magnetic Energy Storage Plant, Advances in

Hassenzahl, W.

2011-01-01T23:59:59.000Z

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


181

MAGNETIC GRID  

DOE Patents (OSTI)

An electronic grid is designed employing magnetic forces for controlling the passage of charged particles. The grid is particularly applicable to use in gas-filled tubes such as ignitrons. thyratrons, etc., since the magnetic grid action is impartial to the polarity of the charged particles and, accordingly. the sheath effects encountered with electrostatic grids are not present. The grid comprises a conductor having sections spaced apart and extending in substantially opposite directions in the same plane, the ends of the conductor being adapted for connection to a current source.

Post, R.F.

1960-08-01T23:59:59.000Z

182

Hyper-resistivity and electron thermal conductivity due to destroyed magnetic surfaces in axisymmetric plasma equilibria  

Science Conference Proceedings (OSTI)

In order to model the effects of small-scale current-driven magnetic fluctuations in a mean-field theoretical description of a large-scale plasma magnetic field B(x,t), a space and time dependent hyper-resistivity {Lambda}(x,t) can be incorporated into the Ohm's law for the parallel electric field E Dot-Operator B. Using Boozer coordinates, a theoretical method is presented that allows for a determination of the hyper-resistivity {Lambda}({psi}) functional dependence on the toroidal magnetic flux {psi} for arbitrary experimental steady-state Grad-Shafranov axisymmetric plasma equilibria, if values are given for the parallel plasma resistivity {eta}({psi}) and the local distribution of any auxiliary plasma current. Heat transport in regions of plasma magnetic surfaces destroyed by resistive tearing modes can then be modeled by an electron thermal conductivity k{sub e}({psi})=({epsilon}{sub 0}{sup 2}m{sub e}/e{sup 2}){Lambda}({psi}), where e and m{sub e} are the electron charge and mass, respectively, while {epsilon}{sub 0} is the permittivity of free space. An important result obtained for axisymmetric plasma equilibria is that the {psi}{psi}-component of the metric tensor of Boozer coordinates is given by the relation g{sup {psi}{psi}}({psi}){identical_to}{nabla}{psi} Dot-Operator {nabla}{psi}=[{mu}{sub 0}G({psi})][{mu}{sub 0}I({psi})]/{iota}({psi}), with {mu}{sub 0} the permeability of free space, G({psi}) the poloidal current outside a magnetic surface, I({psi}) the toroidal current inside a magnetic surface, and {iota}({psi}) the rotational transform.

Weening, R. H. [Department of Radiologic Sciences, Thomas Jefferson University, 901 Walnut Street, Philadelphia, Pennsylvania 19107-5233 (United States)

2012-06-15T23:59:59.000Z

183

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Title: Scanning tunneling microscope; Semiconductor; Spintronics. Description: [Left] A high resolution STM image of a manganese ...

184

SPIE Medical Imaging Medical Imaging  

E-Print Network (OSTI)

1 SPIE Medical Imaging 2006 1 Medical Imaging Fundamentals Kenneth H. Wong, Ph.D. Division of Computer Assisted Interventions and Medical Robotics (CAIMR) Imaging Science and Information Systems (ISIS) Center Department of Radiology Georgetown University SPIE Medical Imaging 2006 2 Main Themes · Describe

Miga, Michael I.

185

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Title: Nanotechnology--Nanomanufacturing; Optical Nano Vision. Description: A new optical imaging technology under ...

186

Carbon Joins the Magnetic Club  

NLE Websites -- All DOE Office Websites (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 carbon," said Hendrik Ohldag, the paper's lead author and SSRL staff scientist. "Unfortunately, they realized later that they were misled by small amounts of iron, cobalt or nickel in their samples." In Leipzig, Ohldag's team applied a beam of protons to disrupt and align a portion of the electrons in samples of pure carbon, magnetizing tiny, measurable spots within the carbon. The team then used the x-ray microscope at ALS to obtain images of the magnetized portions-a measurement only possible with a state-of-the-art microscope that uses the brilliant x-ray beams generated when electrons accelerate around the ring of a synchrotron. The x-ray beam also enabled the team to verify beyond doubt that the sample remained free of impurities during the experiments, unlike the case in previous studies.

187

Questions about Magnets  

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

off just the north (or just the south) end of a magnet? Are magnets stronger than gravity? Hold a magnet in the air. Place a nail against it. The magnet holds the nail up...

188

Frontiers in Chemical Imaging Seminar Series  

E-Print Network (OSTI)

Frontiers in Chemical Imaging Seminar Series Presented by Kannan M. Krishnan, Ph.D. Departments. Central to this work are innovations in chemical synthesis of nanoparticles, their size-dependent magnetic and technological interest, that may provide opportunities for future collaborative research in chemical imaging

189

Is Interleaving in the Agulhas Current Driven by Near-Inertial Velocity Perturbations?  

Science Conference Proceedings (OSTI)

Recent observations taken at a number of latitudes in the Agulhas Current reveal that the water mass structure on either side of its dynamical core is distinctly different. Moreover, interleaving of these distinct water masses is observed at over ...

Lisa M. Beal

2007-04-01T23:59:59.000Z

190

Environmental limits on the non-resonant cosmic-ray current-driven instability  

E-Print Network (OSTI)

We investigate the so-called non-resonant cosmic-ray streaming instability, first discussed by Bell (2004). The extent to which thermal damping and ion-neutral collisions reduce the growth of this instability is calculated. Limits on the growth of the non-resonant mode in SN1006 and RX J1713.7-3946 are presented.

B. Reville; J. G. Kirk; P. Duffy; S. O'Sullivan

2008-02-22T23:59:59.000Z

191

magnets2  

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

II II Painless Physics Articles BEAM COOLING August 2, 1996 By Leila Belkora, Office of Public Affairs ACCELERATION August 16, 1996 By Dave Finley, Accelerator Division Head RF August 30, 1996 By Pat Colestock, Accelerator Division FIXED TARGET PHYSICS September 20, 1996 By Peter H. Garbincius, Physics Section FIXED TARGET PHYSICS PART DEUX October 16, 1996 By Peter H. Garbincius, Physics Section and Leila Belkora, Office of Public Affaris CROSS SECTION November 1, 1996 By Doreen Wackeroth, Theoretical Physics Edited by Leila Belkora, Office of Public Affaris MAGNETS PART I November 15, 1996 By Hank Glass, Technical Support Section Edited by Donald Sena, Office of Public Affairs MAGNETS PART II January 10, 1997 By Hank Glass, Technical Support Section Edited by Donald Sena, Office of Public Affairs

192

Magnetic Reconnection  

SciTech Connect

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.

Masaaki Yamada, Russell Kulsrud and Hantao Ji

2009-09-17T23:59:59.000Z

193

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Title: Carbon Nanotube Measurements. Description: Scanning electron microscope image of 'cleaned' carbon nanotubes at NIST (color added for ...

194

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Description: Engineering design image shows a cross-section of part of the planned ITER fusion reaction vessel. Diverter ...

195

X-Ray Diffraction Microscopy of Magnetic Structures  

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

X-Ray Diffraction Microscopy of Magnetic Structures Print X-Ray Diffraction Microscopy of Magnetic Structures Print science brief icon Scientists working at ALS Beamline 12.0.2.2 have demonstrated a new x-ray technique for producing short-exposure nanoscale images of the magnetic structure of materials. The new method combines aspects of coherent x-ray diffraction, which can determine 3-D charge distributions, and resonant magnetic scattering, which is sensitive to magnetic structures. Physicists have used coherent x-ray diffraction to measure the electron density of complicated molecules. The formula used to make these calculations contains terms that relate to the electron spin of magnetic atoms, but these terms are traditionally ignored since coherent x-ray diffraction has not been used to retrieve magnetic information. Using the full formula allows for the determination of not only the electron density, but also the magnetic spin distribution and its orientation.

196

X-Ray Diffraction Microscopy of Magnetic Structures  

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

X-Ray Diffraction Microscopy of Magnetic Structures Print X-Ray Diffraction Microscopy of Magnetic Structures Print science brief icon Scientists working at ALS Beamline 12.0.2.2 have demonstrated a new x-ray technique for producing short-exposure nanoscale images of the magnetic structure of materials. The new method combines aspects of coherent x-ray diffraction, which can determine 3-D charge distributions, and resonant magnetic scattering, which is sensitive to magnetic structures. Physicists have used coherent x-ray diffraction to measure the electron density of complicated molecules. The formula used to make these calculations contains terms that relate to the electron spin of magnetic atoms, but these terms are traditionally ignored since coherent x-ray diffraction has not been used to retrieve magnetic information. Using the full formula allows for the determination of not only the electron density, but also the magnetic spin distribution and its orientation.

197

X-Ray Diffraction Microscopy of Magnetic Structures  

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

X-Ray Diffraction Microscopy of Magnetic Structures Print X-Ray Diffraction Microscopy of Magnetic Structures Print science brief icon Scientists working at ALS Beamline 12.0.2.2 have demonstrated a new x-ray technique for producing short-exposure nanoscale images of the magnetic structure of materials. The new method combines aspects of coherent x-ray diffraction, which can determine 3-D charge distributions, and resonant magnetic scattering, which is sensitive to magnetic structures. Physicists have used coherent x-ray diffraction to measure the electron density of complicated molecules. The formula used to make these calculations contains terms that relate to the electron spin of magnetic atoms, but these terms are traditionally ignored since coherent x-ray diffraction has not been used to retrieve magnetic information. Using the full formula allows for the determination of not only the electron density, but also the magnetic spin distribution and its orientation.

198

Image Resources  

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

Mosaic of earth and sky images Mosaic of earth and sky images Image Resources Free image resources covering energy, environment, and general science. Here are some links to energy- and environment-related photographic databases. Berkeley Lab Photo Archive Berkeley Lab's online digital image collection. National Science Digital Library (NSDL) NSDL is the Nation's online library for education and research in science, technology, engineering, and mathematics. The World Bank Group Photo Library A distinctive collection of over 11,000 images that illustrate development through topics such as Agriculture, Education, Environment, Health, Trade and more. Calisphere Compiles the digital collections of libraries, museums, and cultural heritage organizations across California, and organizes them by theme, such

199

Superconducting magnet  

DOE Patents (OSTI)

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.

Satti, John A. (Naperville, IL)

1980-01-01T23:59:59.000Z

200

Magnet innovations for linacs  

Science Conference Proceedings (OSTI)

It is possible to produce large magnetic fields at the aperture of permanent magnet quadrupoles, even when the magnetic aperture is very small. That, combined with their compactness, makes permanent magnet quadrupoles very powerful components of small aperture linacs. Results will be presented about past and present work on both fixed and variable strength permanent magnets suitable for use in and around linacs.

Halbach, K.

1986-06-01T23:59:59.000Z

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


201

Studies of the magnetic structure at the ferromagnet - antiferromagnet interface  

SciTech Connect

Antiferromagnetic layers are a scientifically challenging component in magneto-electronic devices such as magnetic sensors in hard disk heads, or magnetic RAM elements. In this paper we show that photo-electron emission microscopy (PEEM) is capable of determining the magnetic structure at the interface of ferromagnets and antiferromagnets with high spatial resolution (down to 20 nm). Dichroism effects at the L edges of the magnetic 3d transition metals, using circularly or linearly polarized soft x-rays from a synchrotron source, give rise to a magnetic image contrast. Images, acquired with the PEEM2 experiment at the Advanced Light Source, show magnetic contrast for antiferromagnetic LaFeO{sub 3}, microscopically resolving the magnetic domain structure in an antiferromagnetically ordered thin film for the first time. Magnetic coupling between LaFeO{sub 3} and an adjacent Co layer results in a complete correlation of their magnetic domain structures. From field dependent measurements a unidirectional anisotropy resulting in a local exchange bias of up to 30 Oe in single domains could be deduced. The elemental specificity and the quantitative magnetic sensitivity render PEEM a perfect tool to study magnetic coupling effects in multi-layered thin film samples.

Scholl, A.; Nolting, F.; Stohr, J.; Luning, J.; Seo, J.W.; Locquet, J.-P.; Anders, S.; Ohldag, H.; Padmore, H.A.

2001-01-02T23:59:59.000Z

202

Magnetics and the body  

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

no magnetic "charges"), such as from electromagnets. Magnetic fields are measured in Tesla (T) or Gauss (G). The Tesla is a very large unit (1 T 10,000 G). Most large magnets...

203

Learning About Magnets!  

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

the National High Magnetic Field Laboratory Learning About Name A magnet is a material or object that creates a magnetic fi eld. This fi eld is invisible, but it creates a force...

204

ALS superbend magnet system  

E-Print Network (OSTI)

ALS Superbend Magnet System J. Zbasnik , S. T. Wang ,of a High-Field Magnet for the ALS, Transactions AppliedRefrigeration options for the ALS Superbend dipole magnets,

2000-01-01T23:59:59.000Z

205

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... on the availability of this image. Title: Tiny Tubes May Aid Pharmacuetical R&D. Description: NIST scientists used pairs of ...

206

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Title: New Imaging Tool is Boon to Fuel Cell Research. ... water being produced and removed inside the maze-like solid housing of fuel cells under a ...

207

Helical Magnets Project | Superconducting Magnet Division  

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

RHIC, the basic construction unit is a superconducting dipole magnet producing a four tesla dipole field that rotates through 360 degrees in a length of 2.4 meters. The magnets...

208

Magnetization of neutron matter  

SciTech Connect

In this paper, we compute magnetization of neutron matter at strong magnetic field using the lowest order constrained variational (LOCV) technique.

Bigdeli, M. [Department of Physics, Zanjan University, P.O. Box 45195-313, Zanjan (Iran, Islamic Republic of)

2011-09-21T23:59:59.000Z

209

SUPERCONDUCTING MAGNETIC ENERGY STORAGE  

E-Print Network (OSTI)

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

Hassenzahl, W.

2011-01-01T23:59:59.000Z

210

NSLS II: Magnetism  

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

spatial ordering of the magnetic moments that is superimposed on the crystal lattice. Why these atomic magnetic moments survive and how they arrange in the solid is the...

211

Regenerator for Magnetic Refrigerants  

Ames Laboratory researchers have developed a new magnetic material that can be used at low temperatures (sub liquid hydrogen) for magnetic refrigerators.

212

Magnetic Switching under Pressure | Advanced Photon Source  

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

Revealing the Secrets of Chemical Bath Deposition Revealing the Secrets of Chemical Bath Deposition DNA Repair Protein Caught in the Act of Molecular Theft Velcro for Nanoparticles A Molecular Fossil Ultrafast Imaging of Electron Waves in Graphene Science Highlights Archives: 2013 | 2012 | 2011 | 2010 2009 | 2008 | 2007 | 2006 2005 | 2004 | 2003 | 2002 2001 | 2000 | 1998 | Subscribe to APS Science Highlights rss feed Magnetic Switching under Pressure DECEMBER 2, 2010 Bookmark and Share A schematic representation of the pressure-induced magnetic switching effect. The colored images highlight the direction of the magnetic orbital (grey plane) for the copper centers (green balls: copper, blue: nitrogen, red: oxygen/water, yellow: fluoride). A material's properties are a critical factor in the way that material

213

Studying Nanoscale Magnetism and its Dynamics with Soft X-ray Microscopy  

Science Conference Proceedings (OSTI)

Magnetic soft X-ray microscopy allows for imaging magnetic structures at a spatial resolution down to 15nm and a time resolution in the sub-100ps regime. Inherent elemental specificity can be used to image the magnetic response of individual components such as layers in multilayered systems. This review highlights current achievements and discusses the future potential of magnetic soft X-ray microscopy at fsec X-ray sources where snapshot images of ultrafast spin dynamics with a spatial resolution below 10nm will become feasible.

Mccall, Monnikue M; Fischer, Peter

2008-05-01T23:59:59.000Z

214

Nanometric Optical Imaging Frontiers in Chemical Imaging  

E-Print Network (OSTI)

Nanometric Optical Imaging Frontiers in Chemical Imaging Seminar Series Presented by... Professor thermal imaging, chemical delivery and other new horizons. Finally, as part of this lecture, Lewis

215

Images, Video, & More  

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

Images, Video, & More Images BABAR Design drawings SLAC Image Gallery: BABAR SLAC Image Gallery: Aerial photos Videos Public lecture on "ANTIMATTER: What is it and where did it...

216

Magnetic Resonance Connectome Automated Pipeline  

E-Print Network (OSTI)

This manuscript presents a novel, tightly integrated pipeline for estimating a connectome, which is a comprehensive description of the neural circuits in the brain. The pipeline utilizes magnetic resonance imaging (MRI) data to produce a high-level estimate of the structural connectivity in the human brain. The Magnetic Resonance Connectome Automated Pipeline (MRCAP) is efficient and its modular construction allows researchers to modify algorithms to meet their specific requirements. The pipeline has been validated and over 200 connectomes have been processed and analyzed to date. This tool enables the prediction and assessment of various cognitive covariates, and this research is applicable to a variety of domains and applications. MRCAP will enable MR connectomes to be rapidly generated to ultimately help spur discoveries about the structure and function of the human brain.

Gray, William R; Vogelstein, Joshua T; Landman, Bennett A; Prince, Jerry L; Vogelstein, R Jacob

2011-01-01T23:59:59.000Z

217

Atomic magnetic gradiometer for room temperature high sensitivity magnetic field detection  

DOE Patents (OSTI)

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.

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)

2009-08-11T23:59:59.000Z

218

DISCONNECTING OPEN SOLAR MAGNETIC FLUX  

SciTech Connect

Disconnection of open magnetic flux by reconnection is required to balance the injection of open flux by coronal mass ejections and other eruptive events. Making use of recent advances in heliospheric background subtraction, we have imaged many abrupt disconnection events. These events produce dense plasma clouds whose distinctive shape can now be traced from the corona across the inner solar system via heliospheric imaging. The morphology of each initial event is characteristic of magnetic reconnection across a current sheet, and the newly disconnected flux takes the form of a 'U-'shaped loop that moves outward, accreting coronal and solar wind material. We analyzed one such event on 2008 December 18 as it formed and accelerated at 20 m s{sup -2} to 320 km s{sup -1}, thereafter expanding self-similarly until it exited our field of view 1.2 AU from the Sun. From acceleration and photometric mass estimates we derive the coronal magnetic field strength to be 8 {mu}T, 6 R{sub Sun} above the photosphere, and the entrained flux to be 1.6 Multiplication-Sign 10{sup 11} Wb (1.6 Multiplication-Sign 10{sup 19} Mx). We model the feature's propagation by balancing inferred magnetic tension force against accretion drag. This model is consistent with the feature's behavior and accepted solar wind parameters. By counting events over a 36 day window, we estimate a global event rate of 1 day{sup -1} and a global solar minimum unsigned flux disconnection rate of 6 Multiplication-Sign 10{sup 13} Wb yr{sup -1} (6 Multiplication-Sign 10{sup 21} Mx yr{sup -1}) by this mechanism. That rate corresponds to {approx} - 0.2 nT yr{sup -1} change in the radial heliospheric field at 1 AU, indicating that the mechanism is important to the heliospheric flux balance.

DeForest, C. E.; Howard, T. A.; McComas, D. J. [Southwest Research Institute, 1050 Walnut Street Suite 300, Boulder, CO 80302 (United States)

2012-01-20T23:59:59.000Z

219

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... from the bright glare in the distance transmit images of a cat-like face at ... Though false color has been added to the cats faces, they are otherwise ...

220

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... a href http://www.nist.gov/public_affairs/images/Nanopore 20device.avi See video /a PHY, DARPA, spectroscopy See also http://www.nist.gov/pml ...

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


221

Nanocomposite Magnets: Transformational Nanostructured Permanent Magnets  

SciTech Connect

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.

None

2010-10-01T23:59:59.000Z

222

HTS Magnet Program | Superconducting Magnet Division  

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

HTS Magnet Program HTS Magnet Program High Temperature Superconductors (HTS) have the potential to revolutionize the field of superconducting magnets for particle accelerators, energy storage and medical applications. This is because of the fact that as compared to the conventional Low Temperature Superconductors (LTS), the critical current density (Jc ) of HTS falls slowly both: as a function of increasing field, and as a function of increasing temperature These unique properties can be utilized to design and build: HTS magnets that produce very high fields (20 - 50 T) HTS magnets that operate at elevated temperatures (20 - 77 K) This is a significant step forward over the convention LTS magnets which generally operate at a temperature of ~4 K and with field usually limited

223

Object extraction from T2 weighted brain MR image using histogram based gradient calculation  

Science Conference Proceedings (OSTI)

Several segmentation methods have been reported with their own pros and cons. Here we proposed a method for object extraction from T2 weighted (T2) brain magnetic resonance (MR) images. The proposed method is purely based on histogram processing for ... Keywords: Cerebrospinal fluid, Gray matter, Magnetic resonance imaging, Object extraction, White matter

Ghulam Gilanie, Muhammad Attique, Hafeez-Ullah, Shahid Naweed, Ejaz Ahmed, Masroor Ikram

2013-09-01T23:59:59.000Z

224

History Images  

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

History Images History Images Los Alamos History in Images Los Alamos has a proud history and heritage of almost 70 years of science and innovation. The people of the Laboratory work on advanced technologies to provide the best scientific and engineering solutions to many of the nation's most crucial security challenges. Click thumbnails to enlarge. Photos arranged by most recent first, horizontal formats before vertical. See Flickr for more sizes and details. Back in the day Back in the day LA bridge in Los Alamos LA bridge in Los Alamos 1945 Army-Navy "E" Award 1945 Army-Navy "E" Award Louis Rosen Louis Rosen Bob Van Ness Robert Kuckuck and Michael Anastasio Bob Van Ness Robert Kuckuck and Michael Anastasio TA-18 TA-18 Elmer Island TU-4 assembly area Elmer Island TU-4 assembly area

225

Stellar Imager (SI): developing and testing a predictive dynamo model for the Sun by imaging other stars  

E-Print Network (OSTI)

The Stellar Imager mission concept is a space-based UV/Optical interferometer designed to resolve surface magnetic activity and subsurface structure and flows of a population of Sun-like stars, in order to accelerate the development and validation of a predictive dynamo model for the Sun and enable accurate long-term forecasting of solar/stellar magnetic activity.

Carpenter, Kenneth G; Karovska, Margarita; Kraemer, Steve; Lyon, Richard; Mozurkewich, David; Airapetian, Vladimir; Adams, John C; Allen, Ronald J; Brown, Alex; Bruhweiler, Fred; Conti, Alberto; Christensen-Dalsgaard, Joergen; Cranmer, Steve; Cuntz, Manfred; Danchi, William; Dupree, Andrea; Elvis, Martin; Evans, Nancy; Giampapa, Mark; Harper, Graham; Hartman, Kathy; Labeyrie, Antoine; Leitner, Jesse; Lillie, Chuck; Linsky, Jeffrey L; Lo, Amy; Mighell, Ken; Miller, David; Noecker, Charlie; Parrish, Joe; Phillips, Jim; Rimmele, Thomas; Saar, Steve; Sasselov, Dimitar; Stahl, H Philip; Stoneking, Eric; Strassmeier, Klaus; Walter, Frederick; Windhorst, Rogier; Woodgate, Bruce; Woodruff, Robert

2010-01-01T23:59:59.000Z

226

Tamper resistant magnetic stripes  

DOE Patents (OSTI)

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.

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

1999-01-01T23:59:59.000Z

227

Agentification of Markov model-based segmentation: Application to magnetic resonance brain scans  

Science Conference Proceedings (OSTI)

Objective: Markov random field (MRF) models have been traditionally applied to the task of robust-to-noise image segmentation. Most approaches estimate MRF parameters on the whole image via a global expectation-maximization (EM) procedure. The resulting ... Keywords: Distributed expectation maximization, Magnetic resonance brain scan segmentation, Markov random field, Medical imaging, Multiagents system

Benoit Scherrer; Michel Dojat; Florence Forbes; Catherine Garbay

2009-05-01T23:59:59.000Z

228

Direct Imaging of Antiferromagnetic Vortex States  

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

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

229

Direct Imaging of Antiferromagnetic Vortex States  

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

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

230

Direct Imaging of Antiferromagnetic Vortex States  

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

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

231

Stochastic Domain-Wall Depinning in Magnetic Nanowires  

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

Stochastic Domain-Wall Depinning in Magnetic Nanowires Print Stochastic Domain-Wall Depinning in Magnetic Nanowires Print 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 microscopy images by a Berkeley Lab-University of Hamburg group has now revealed that the stochastic behavior of the domain-wall depinning field in notch-patterned Ni80Fe20 (permalloy) nanowires depends strongly on the wire width and the notch depth. This result both provides valuable insight into the motion of magnetic-domain walls and opens a path to further technological developments in spintronics applications.

232

Stochastic Domain-Wall Depinning in Magnetic Nanowires  

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

Stochastic Domain-Wall Depinning in Magnetic Nanowires Print Stochastic Domain-Wall Depinning in Magnetic Nanowires Print 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 microscopy images by a Berkeley Lab-University of Hamburg group has now revealed that the stochastic behavior of the domain-wall depinning field in notch-patterned Ni80Fe20 (permalloy) nanowires depends strongly on the wire width and the notch depth. This result both provides valuable insight into the motion of magnetic-domain walls and opens a path to further technological developments in spintronics applications.

233

Argonne CNM Highlight: Biofunctionalized magnetic-vortex microdiscs for  

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

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

234

Stochastic Domain-Wall Depinning in Magnetic Nanowires  

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

Stochastic Domain-Wall Depinning 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 microscopy images by a Berkeley Lab-University of Hamburg group has now revealed that the stochastic behavior of the domain-wall depinning field in notch-patterned Ni80Fe20 (permalloy) nanowires depends strongly on the wire width and the notch depth. This result both provides valuable insight into the motion of magnetic-domain walls and opens a path to further technological developments in spintronics applications.

235

Stochastic Domain-Wall Depinning in Magnetic Nanowires  

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

Stochastic Domain-Wall Depinning in Magnetic Nanowires Print Stochastic Domain-Wall Depinning in Magnetic Nanowires Print 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 microscopy images by a Berkeley Lab-University of Hamburg group has now revealed that the stochastic behavior of the domain-wall depinning field in notch-patterned Ni80Fe20 (permalloy) nanowires depends strongly on the wire width and the notch depth. This result both provides valuable insight into the motion of magnetic-domain walls and opens a path to further technological developments in spintronics applications.

236

Stochastic Domain-Wall Depinning in Magnetic Nanowires  

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

Stochastic Domain-Wall Depinning in Magnetic Nanowires Print Stochastic Domain-Wall Depinning in Magnetic Nanowires Print 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 microscopy images by a Berkeley Lab-University of Hamburg group has now revealed that the stochastic behavior of the domain-wall depinning field in notch-patterned Ni80Fe20 (permalloy) nanowires depends strongly on the wire width and the notch depth. This result both provides valuable insight into the motion of magnetic-domain walls and opens a path to further technological developments in spintronics applications.

237

Stochastic Domain-Wall Depinning in Magnetic Nanowires  

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

Stochastic Domain-Wall Depinning in Magnetic Nanowires Print Stochastic Domain-Wall Depinning in Magnetic Nanowires Print 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 microscopy images by a Berkeley Lab-University of Hamburg group has now revealed that the stochastic behavior of the domain-wall depinning field in notch-patterned Ni80Fe20 (permalloy) nanowires depends strongly on the wire width and the notch depth. This result both provides valuable insight into the motion of magnetic-domain walls and opens a path to further technological developments in spintronics applications.

238

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

SciTech Connect

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.

Yun, J.; St Aubin, J.; Rathee, S.; Fallone, B. G. [Department of Physics, University of Alberta, 11322-89 Avenue, Edmonton, Alberta T6G 2G7 (Canada) and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Physics, University of Alberta, 11322-89 Avenue, Edmonton, Alberta T6G 2G7 (Canada); Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada)

2010-05-15T23:59:59.000Z

239

LHC Magnet Program | Superconducting Magnet Division  

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

Magnet Program Magnet Program The Superconducting Magnet Division is building a number of dipole magnets for the Large Hadron Collider (LHC), which is now under construction at CERN in Geneva, Switzerland. Scheduled to begin operation in 2007, this machine will collide beams of protons with the unprecedented energy of 7 TeV per beam to explore the nature of matter at its most basic level (RHIC can collide beams of protons with energies of 0.25 TeV, but is mostly used to collide heavy ions with energies of 0.1 TeV per nucleon). The magnets are being built as part of the US program, recommended by the High Energy Physics Advisory Panel (HEPAP) and approved by Congress, to contribute to the construction and, later, use of that frontier machine by the US high energy physics community. Fermi National Accelerator Laboratory (FNAL) and

240

Active magnetic regenerator  

SciTech Connect

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.

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

1982-01-01T23:59:59.000Z

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


241

ALS superbend magnet performance  

E-Print Network (OSTI)

ALS Superbend Magnet Performance S. Marks, J. Zbasnik, W.the Advanced Light Source (ALS), with the fourth magnet as ahe Advanced Light Source (ALS) at the Lawrence Berkeley

2001-01-01T23:59:59.000Z

242

Feature-based fusion of medical imaging data  

Science Conference Proceedings (OSTI)

The acquisition of multiple brain imaging types for a given study is a very common practice. There have been a number of approaches proposed for combining or fusing multitask or multimodal information. These can be roughly divided into those that attempt ... Keywords: Data fusion, EEG, functional magnetic resonance imaging (fMRI), independent component analysis (ICA), multivariate data analysis

Vince D. Calhoun; Tlay Adali

2009-09-01T23:59:59.000Z

243

Superconducting magnet of Aurora  

Science Conference Proceedings (OSTI)

The AURORAsuperconducting magnet system is composed of a cylindrical single?body magnet and a refrigeration system for superconducting coils. The magnet generates B z =1 T on the central orbit at the 150 MeV electron beam injection energy and B z =4.3 T at the 650 MeV storage energy. The diameter of the central orbit is 1 m. Iron poles and yokes are used for shielding the magnetic field

T. Takayama; SHI Accelerator Research Group

1989-01-01T23:59:59.000Z

244

Magnetic Materials Staff  

Science Conference Proceedings (OSTI)

... Materials Science and Engineering Division Staff Directory; MML Organization. Contact. Magnetic Materials Group Robert Shull, Group Leader. ...

2012-10-09T23:59:59.000Z

245

Minimum Magnetic Energy Theorem  

E-Print Network (OSTI)

The Thomson's Theorem states that static charge distributions in conductors show up at the conducting surfaces in an equipotential configuration, so that the electrostatic energy is a minimum. In this work we study an analogue statement for magnetic systems: in a given set of conductors, the stored magnetic field energy reaches the minimum value for superficial current distributions so that the magnetic vector potential is tangent to the conductors surfaces. This is the counterpart of Thomson's theorem for the magnetic field.

Fiolhais, M C N

2008-01-01T23:59:59.000Z

246

Magnetic Nanoparticle Metrology  

Science Conference Proceedings (OSTI)

... T2 relaxation times, hysteretic energy loss, etc ... Optimization of magnetic nanoparticle synthesis for ... competition between lattice energies and dipolar ...

2012-12-03T23:59:59.000Z

247

Irreversible magnetic switch  

DOE Patents (OSTI)

This invention is comprised of an irreversible magnetic switch containing a ferromagnetic amorphous metal having a predetermined crystallization temperature in its inductor magnetic path. With the incorporation of such material, the magnetic properties after cooling from a high temperature excursion above its crystallization temperature are only a fraction of the original value. The difference is used to provide a safety feature in the magnetic switch.

Karnowsky, M.M.; Yost, F.G.

1991-12-31T23:59:59.000Z

248

Non-Uniform Switching of the Perpendicular Magnetization in a Spin-Torque Magnetic Nanopillar  

SciTech Connect

Time-resolved scanning transmission x-ray microscopy (STXM) measurements were performed to study the current-induced magnetization switching mechanism in nanopillars exhibiting strong perpendicular magnetic anisotropy (PMA). This technique provides both short time (70 ps) and high spatial (25 nm) resolution. Direct imaging of the magnetization demonstrates that, after an incubation time of {approx} 1.3 ns, a 100 x 300 nm{sup 2} ellipsoidal device switches in {approx} 1 ns via a central domain nucleation and opposite propagation of two domain walls towards the edges. High domain wall velocities on the order of 100m/s are measured. Micromagnetic simulations are shown to be in good agreement with experimental results and provide insight into magnetization dynamics during the incubation and reversal period.

Bernstein, David

2011-06-01T23:59:59.000Z

249

Magnetic nanohole superlattices  

DOE Patents (OSTI)

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.

Liu, Feng

2013-05-14T23:59:59.000Z

250

Tunable Magnetic Regenerator/Refrigerant  

Magnetic regenerators utilize the magnetocaloric effect--the ability of a magnetic field to reduce the magnetic part of a solid materials entropy, generating heat, and then removing the magnetic field, permitting the reduction of temperature with the ...

251

Imaging bolometer  

DOE Patents (OSTI)

Radiation-hard, steady-state imaging bolometer. A bolometer employing infrared (IR) imaging of a segmented-matrix absorber of plasma radiation in a cooled-pinhole camera geometry is described. The bolometer design parameters are determined by modeling the temperature of the foils from which the absorbing matrix is fabricated by using a two-dimensional time-dependent solution of the heat conduction equation. The resulting design will give a steady-state bolometry capability, with approximately 100 Hz time resolution, while simultaneously providing hundreds of channels of spatial information. No wiring harnesses will be required, as the temperature-rise data will be measured via an IR camera. The resulting spatial data may be used to tomographically investigate the profile of plasmas.

Wurden, Glen A. (Los Alamos, NM)

1999-01-01T23:59:59.000Z

252

Imaging bolometer  

DOE Patents (OSTI)

Radiation-hard, steady-state imaging bolometer is disclosed. A bolometer employing infrared (IR) imaging of a segmented-matrix absorber of plasma radiation in a cooled-pinhole camera geometry is described. The bolometer design parameters are determined by modeling the temperature of the foils from which the absorbing matrix is fabricated by using a two-dimensional time-dependent solution of the heat conduction equation. The resulting design will give a steady-state bolometry capability, with approximately 100 Hz time resolution, while simultaneously providing hundreds of channels of spatial information. No wiring harnesses will be required, as the temperature-rise data will be measured via an IR camera. The resulting spatial data may be used to tomographically investigate the profile of plasmas. 2 figs.

Wurden, G.A.

1999-01-19T23:59:59.000Z

253

Neutron Imaging Explored as Complementary Technique for Improving Cancer  

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

Neutron Imaging Explored as Complementary Technique for Improving Cancer Neutron Imaging Explored as Complementary Technique for Improving Cancer Detection August 05, 2013 Researcher Maria Cekanova analyzes the neutron radiographs of a canine breast tumor (black color in top image of monitor screen) using the software to visualize in color the various intensities of neutron transmissions through the breast tissue. ORNL and University of Tennessee collaboration now analyzing first results from neutron radiographs of cancerous tissue samples Today's range of techniques for detection of breast and other cancers include mammography, computed tomography (CT), magnetic resonance imaging (MRI), ultrasound, positron emission tomography (PET), and optical imaging. Each technology has advantages and disadvantages, with limitations either

254

Magnetic damping for maglev  

DOE Green Energy (OSTI)

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

Chen, S.S.; Zhu, S.; Cai, Y.; Rote, D.M. [Argonne National Lab., IL (United States). Energy Technology Div.

1994-12-31T23:59:59.000Z

255

Magnetically attached sputter targets  

DOE Patents (OSTI)

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.

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

1994-02-15T23:59:59.000Z

256

Perfusion Estimated With Rapid Dynamic Contrast-Enhanced Magnetic Resonance Imaging Correlates Inversely With Vascular Endothelial Growth Factor Expression and Pimonidazole Staining in Head-and-Neck Cancer: A Pilot Study  

Science Conference Proceedings (OSTI)

Purpose: To analyze, in a pilot study, rapidly acquired dynamic contrast-enhanced (DCE)-MRI data with a general two-compartment exchange tracer kinetic model and correlate parameters obtained with measurements of hypoxia and vascular endothelial growth factor (VEGF) expression in patients with squamous cell carcinoma of the head and neck. Methods and Materials: Eight patients were scanned before surgery. The DCE-MRI data were acquired with 1.5-s temporal resolution and analyzed using the two-compartment exchange tracer kinetic model to obtain estimates of parameters including perfusion and permeability surface area. Twelve to 16 h before surgery, patients received an intravenous injection of pimonidazole. Samples taken during surgery were used to determine the level of pimonidazole staining using immunohistochemistry and VEGF expression using quantitative real-time polymerase chain reaction. Correlations between the biological and imaging data were examined. Results: Of the seven tumors fully analyzed, those that were poorly perfused tended to have high levels of pimonidazole staining (r = -0.79, p = 0.03) and VEGF expression (r = -0.82, p = 0.02). Tumors with low permeability surface area also tended to have high levels of hypoxia (r = -0.75, p = 0.05). Hypoxic tumors also expressed higher levels of VEGF (r = 0.82, p = 0.02). Conclusions: Estimates of perfusion obtained with rapid DCE-MRI data in patients with head-and-neck cancer correlate inversely with pimonidazole staining and VEGF expression.

Donaldson, Stephanie B., E-mail: Stephanie.donaldson@physics.cr.man.ac.uk [School of Cancer and Enabling Sciences, University of Manchester, Manchester (United Kingdom) and North Western Medical Physics, The Christie, Manchester (United Kingdom); Betts, Guy [School of Cancer and Enabling Sciences, University of Manchester, Manchester (United Kingdom); Bonington, Suzanne C. [Department of Radiology, The Christie, Manchester (United Kingdom); Homer, Jarrod J. [School of Cancer and Enabling Sciences, University of Manchester, Manchester (United Kingdom); Department of Otolaryngology-Head-and-Neck Surgery, Manchester Royal Infirmary, Manchester (United Kingdom); Slevin, Nick J. [Department of Clinical Oncology, The Christie, Manchester (United Kingdom); Kershaw, Lucy E.; Valentine, Helen [School of Cancer and Enabling Sciences, University of Manchester, Manchester (United Kingdom); West, Catharine M.L. [School of Cancer and Enabling Sciences, University of Manchester, Manchester Academic Health Science Centre, Manchester (United Kingdom); Buckley, David L. [School of Cancer and Enabling Sciences, University of Manchester, Manchester (United Kindgom) and Division of Medical Physics, University of Leeds, Leeds (United Kingdom)

2011-11-15T23:59:59.000Z

257

Status of LDRD-DR 20070518 development of a magnetically driven target for thermo-nuclear burn studies (u)  

SciTech Connect

This project is developing a magnetically driven cylindrical confinement system for the creation of a small region of material existing under extreme conditions. Using a Ranchero High Explosive Pulsed Power generator (HEPP) with maximum current ranging from 25- 50 MA depending on the load, a current driven Al cylinder will impact a series of nested, less massive Au shells. Each subsequent shell's inner surface velocity will increase due to it's smaller mass by the ratio 2.01( 1+ m{sub i+ 1}/m i), along with radial convergence. Attaining this ideal result requires highly efficient energy transfer which in turn requires plastic cushions. The final velocity of the last sequential shell will be used to drive a central experimental package in which extreme material conditions will be produced. The inexpensive nature of HEPP and the extreme conditions attainable allow many studies to be conducted in regimes not currently available in the laboratory. One potential central experimental package consists of a cylindrical Inertial Confinement Fusion (ICF) target; a cylindrical Au pusher surrounding frozen DT. This target is used as a design tool. The ICF conditions achieved with such a target would be similar to those created in a double shell ignition capsule at the National Ignition Facility. The system being developed has a range of potential applications.

Watt, Robert G [Los Alamos National Laboratory; Atchison, W L [Los Alamos National Laboratory; Colgate, S A [Los Alamos National Laboratory; Gofoeth, J [Los Alamos National Laboratory; Griego, J [Los Alamos National Laboratory; Guzik, J [Los Alamos National Laboratory; Holtkamp, D [Los Alamos National Laboratory; Idzorek, G [Los Alamos National Laboratory; Kirkpatrick, R [Los Alamos National Laboratory; Menikoff, R [Los Alamos National Laboratory; Meyer, R [Los Alamos National Laboratory; Oona, H [Los Alamos National Laboratory; Reardon, P [Los Alamos National Laboratory; Rousculp, C L [Los Alamos National Laboratory; Sgro, A G [Los Alamos National Laboratory; Tabaka, L [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

258

2-3 High Field Magnetic Resonance Facility  

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

HFMRF Overview HFMRF Overview High Field Magnetic Resonance Facility A significant portion of research conducted in the High Field Magnetic Resonance Facility (HFMRF) focuses on developing a fundamental, molecular-level understanding of biochemi- cal and biological systems and their response to environmental effects. A secondary focus is in materials science and catalysis and the chemical mechanisms and processes that operate in these areas. Resident and matrixed research staff within this facility offer expertise in the areas of structural biology, solid-state materials characterization, and magnetic resonance imaging (MRI) techniques. Instrumentation & Capabilities NMR * 900-MHz NMR (operational in 2004) * 800-MHz NMR * 750-MHz NMR * 600-MHz NMR (2 systems)

259

High Field Magnet R&D |Superconducting Magnet Division  

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

High Field Magnet R&D High Field Magnet R&D The Superconducting Magnet Division is developing advanced magnet designs and magnet-related technologies for high field accelerator magnets. We are currently working on magnets for three inter-related programs: High Field Magnets for Muon Collider Papers, Presentations Common Coil Magnets Papers, Presentations Interaction Region Magnets Papers, Presentations High Temperature Superconductor (HTS) Magnets Papers, Presentations This is part of a multi-lab superconducting magnet development program for new accelerator facilities that would be part of the U.S. High Energy Physics program. These programs (@BNL, @FNAL, @LBNL) are quite complimentary to each other, so that magnet designs and technologies developed at one laboratory can be easily transferred to another. The BNL

260

Cool Magnetic Molecules  

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

Cool Magnetic Molecules 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 considerations as well as by recent improvements in our ability to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to characterize the design of such "molecular coolers." The work targets the synthesis of molecular cluster compounds containing many unpaired electrons ("nanomagnets") for applications involving enhanced magnetic refrigeration at very low temperatures.

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


261

Core-Shell Structured Magnetic Ternary Nanocubes  

DOE Green Energy (OSTI)

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

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

2010-12-01T23:59:59.000Z

262

Dynamic Switching of the Spin Circulation in Tapered Magnetic Nanodisks  

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

Dynamic Switching of the Spin Dynamic Switching of the Spin Circulation in Tapered Magnetic Nanodisks Dynamic Switching of the Spin Circulation in Tapered Magnetic Nanodisks Print Monday, 22 April 2013 12:09 fischer-magnetic vortices Ferromagnetic NiFe disks (500-nm-wide and 20-nm-thick), were fabricated by e-beam lithography onto a waveguide structure. Field pulses, generated by launching current pulses into the waveguide trigger the magnetization dynamics in the elements. Using the soft x-ray microscope XM-1 providing 25-nm spatial resolution, circularly polarized soft x-rays give rise to XMCD contrast which allows to record an image of the in-plane circulation of the magnetic vortex. The topology of vortices-areas where there is a spinning motion around an imaginary axis-is a physical phenomenon which is found across a large

263

Nanoscale magnetic field mapping with a single spin scanning probe magnetometer  

SciTech Connect

We demonstrate quantitative magnetic field mapping with nanoscale resolution, by applying a lock-in technique on the electron spin resonance frequency of a single nitrogen-vacancy defect placed at the apex of an atomic force microscope tip. In addition, we report an all-optical magnetic imaging technique which is sensitive to large off-axis magnetic fields, thus extending the operation range of diamond-based magnetometry. Both techniques are illustrated by using a magnetic hard disk as a test sample. Owing to the non-perturbing and quantitative nature of the magnetic probe, this work should open up numerous perspectives in nanomagnetism and spintronics.

Rondin, L.; Tetienne, J.-P.; Spinicelli, P.; Roch, J.-F.; Jacques, V. [Laboratoire de Photonique Quantique et Moleculaire, Ecole Normale Superieure de Cachan and CNRS UMR 8537, 94235 Cachan Cedex (France); Dal Savio, C.; Karrai, K. [Attocube systems AG, Koeniginstrasse 11A RGB, Munich 80539 (Germany); Dantelle, G. [Laboratoire de Physique de la Matiere Condensee, Ecole Polytechnique and CNRS UMR 7643, 91128 Palaiseau (France); Thiaville, A.; Rohart, S. [Laboratoire de Physique des Solides, Universite Paris-Sud and CNRS UMR 8502, 91405 Orsay (France)

2012-04-09T23:59:59.000Z

264

Pulse magnetic welder  

DOE Patents (OSTI)

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.

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

1984-01-01T23:59:59.000Z

265

Magnetic latching solenoid  

DOE Patents (OSTI)

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.

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

1995-01-01T23:59:59.000Z

266

Magnetic spectroscopy and microscopy of functional materials  

SciTech Connect

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).

Jenkins, C.A.

2011-01-28T23:59:59.000Z

267

New imaging technique provides improved insight into controlling the plasma  

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

New imaging technique provides improved insight into controlling the plasma New imaging technique provides improved insight into controlling the plasma in fusion experiments By John Greenwald December 9, 2013 Tweet Widget Facebook Like Google Plus One Graphic representation of 2D images of fluctuating electron temperatures in a cross-section of a confined fusion plasma. Graphic representation of 2D images of fluctuating electron temperatures in a cross-section of a confined fusion plasma. A key issue for the development of fusion energy to generate electricity is the ability to confine the superhot, charged plasma gas that fuels fusion reactions in magnetic devices called tokamaks. This gas is subject to instabilities that cause it to leak from the magnetic fields and halt fusion reactions. Now a recently developed imaging technique can help researchers improve

268

New imaging technique provides improved insight into controlling the plasma  

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

New imaging technique provides improved insight into controlling the plasma New imaging technique provides improved insight into controlling the plasma in fusion experiments By John Greenwald December 9, 2013 Tweet Widget Facebook Like Google Plus One Graphic representation of 2D images of fluctuating electron temperatures in a cross-section of a confined fusion plasma. Graphic representation of 2D images of fluctuating electron temperatures in a cross-section of a confined fusion plasma. A key issue for the development of fusion energy to generate electricity is the ability to confine the superhot, charged plasma gas that fuels fusion reactions in magnetic devices called tokamaks. This gas is subject to instabilities that cause it to leak from the magnetic fields and halt fusion reactions. Now a recently developed imaging technique can help researchers improve

269

Nanostructrured Magnetic Materials  

Science Conference Proceedings (OSTI)

Aug 8, 2013 ... The demand for OFF-ON becomes increasingly important as ... The residual magnetic flux density and maximum energy product of the...

270

Magnetically leviated superconducting bearing  

DOE Patents (OSTI)

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.

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

1993-01-01T23:59:59.000Z

271

Rare Earth Magnets  

Science Conference Proceedings (OSTI)

Mar 6, 2013 ... Performance and Endurance of Nd-Fe-B Sintered Magnets in E-Motor Application Conditions: Martina Moore1; Ralph Sueptitz1; Margitta...

272

Rare Earth Magnets  

Science Conference Proceedings (OSTI)

Aug 8, 2013 ... Current high performance permanent magnets (PM) for traction motors of (hybrid) electric vehicles use substantial amount of Dy in Nd-Fe-B...

273

Magnetic Materials and Properties  

Science Conference Proceedings (OSTI)

Aug 5, 2013 ... Following vacuum distillation of the Mg-RE alloy, 98% pure RE metals can be recovered, which are then used to synthesize permanent magnet...

274

Magnetism Highlights| Neutron Science | ORNL  

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

Magnetism Magnetism SHARE Magnetism Highlights 1-5 of 5 Results ARCS maps collaborative magnetic spin behavior in iron telluride December 01, 2011 - Researchers have long thought that magnetism and superconductivity are mutually exclusive. The former typically involves localized atomic electrons. The latter requires freely propagating, itinerant electrons. Unexpected Magnetic Excitations in Doped Insulator Surprise Researchers October 01, 2011 - When doping a disordered magnetic insulator material with atoms of a nonmagnetic material, the conventional wisdom is that the magnetic interactions between the magnetic ions in the material will be weakened. Neutron Analysis Reveals Unique Atomic-Scale Behavior of "Cobalt Blue" September 01, 2011 - Neutron scattering studies of "cobalt blue," a

275

Revealing the Degree of Magnetic Frustration by Non-Magnetic Impurities  

SciTech Connect

Imaging the magnetic fields around a non-magnetic impurity can provide a clear benchmark for quantifying the degree of magnetic frustration. Focusing on the strongly frustrated J{sub 1}-J{sub 2} model and the spatially anisotropic J{sub 1a}-J{sub 1b}-J{sub 2} model, very distinct low energy behaviors reflect different levels of magnetic frustration. In the J{sub 1}-J{sub 2} model, bound magnons appear trapped near the impurity in the ground state and strongly reduce the ordered moments for sites proximal to the impurity. In contrast, local moments in the J{sub 1a}-J{sub 1b}-J{sub 2} model are enhanced on the impurity neighboring sites. These theoretical predictions can be probed by experiments such as nuclear magnetic resonance and scanning tunneling microscopy, and the results can elucidate the role of frustration in antiferromagnets and help narrow the possible models to understand magnetism in the iron pnictdies.

Not Available

2011-08-12T23:59:59.000Z

276

FIRST SIMULTANEOUS DETECTION OF MOVING MAGNETIC FEATURES IN PHOTOSPHERIC INTENSITY AND MAGNETIC FIELD DATA  

SciTech Connect

The formation and the temporal evolution of a bipolar moving magnetic feature (MMF) was studied with high-spatial and temporal resolution. The photometric properties were observed with the New Solar Telescope at Big Bear Solar Observatory using a broadband TiO filter (705.7 nm), while the magnetic field was analyzed using the spectropolarimetric data obtained by Hinode. For the first time, we observed a bipolar MMF simultaneously in intensity images and magnetic field data, and studied the details of its structure. The vector magnetic field and the Doppler velocity of the MMF were also studied. A bipolar MMF with its positive polarity closer to the negative penumbra formed, accompanied by a bright, filamentary structure in the TiO data connecting the MMF and a dark penumbral filament. A fast downflow ({<=}2 km s{sup -1}) was detected at the positive polarity. The vector magnetic field obtained from the full Stokes inversion revealed that a bipolar MMF has a U-shaped magnetic field configuration. Our observations provide a clear intensity counterpart of the observed MMF in the photosphere, and strong evidence of the connection between the MMF and the penumbral filament as a serpentine field.

Lim, Eun-Kyung; Yurchyshyn, Vasyl; Goode, Philip, E-mail: eklim@bbso.njit.edu [Big Bear Solar Observatory, New Jersey Institute of Technology, 40386 North Shore Lane, Big Bear City, CA 92314-9672 (United States)

2012-07-01T23:59:59.000Z

277

BEPC-II Magnet Project | Superconducting Magnet Division  

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

BEPC-II Magnet Project BEPC-II Magnet Project Project Overview The BEPC-II magnets are Interaction Region magnets to be used as part of an upgrade to the Beijing Electron Positron Collider. Two magnets will be produced, both of which will be inserted within the solenoidal detector at one of the collision points. Since the best use of the quadrupole focusing in this case requires placing the magnet as close to the collision point as possible, these magnets will be used within the magnetic field of the detector. This constrains the materials that can be used for construction to only non-magnetic materials. It also places severe demands on the structure of the magnet and it's holding supports due to the reaction forces between the solenoid and the magnet. To create the coil pattern for the final magnet, the coils will be

278

FM DANTE fast imaging and variations: emerging rf-based ultrafast imaging techniques  

Science Conference Proceedings (OSTI)

Keywords: DANTE fast imaging, NMR, burst imaging, fast chemical shift imaging, fast imaging, fast spectroscopic imaging, fast susceptibility imaging

Z. H. Cho; Y. M. Ro; I. K. Hong

1998-01-01T23:59:59.000Z

279

Passive magnetic bearing configurations  

Science Conference Proceedings (OSTI)

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.

Post, Richard F. (Walnut Creek, CA)

2011-01-25T23:59:59.000Z

280

EXOTIC MAGNETS FOR ACCELERATORS.  

SciTech Connect

Over the last few years, several novel magnet designs have been introduced to meet the requirements of new, high performance accelerators and beam lines. For example, the FAIR project at GSI requires superconducting magnets ramped at high rates ({approx} 4 T/s) in order to achieve the design intensity. Magnets for the RIA and FAIR projects and for the next generation of LHC interaction regions will need to withstand high doses of radiation. Helical magnets are required to maintain and control the polarization of high energy protons at RHIC. In other cases, novel magnets have been designed in response to limited budgets and space. For example, it is planned to use combined function superconducting magnets for the 50 GeV proton transport line at J-PARC to satisfy both budget and performance requirements. Novel coil winding methods have been developed for short, large aperture magnets such as those used in the insertion region upgrade at BEPC. This paper will highlight the novel features of these exotic magnets.

WANDERER, P.

2005-09-18T23:59:59.000Z

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


281

Split image optical display  

DOE Patents (OSTI)

A video image is displayed from an optical panel by splitting the image into a plurality of image components, and then projecting the image components through corresponding portions of the panel to collectively form the image. Depth of the display is correspondingly reduced.

Veligdan, James T. (Manorville, NY)

2007-05-29T23:59:59.000Z

282

Superconducting Magnet Division  

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

3 - 6/13/06 3 - 6/13/06 Superconducting Magnet Division S&T Committee Program Review June 22-23, 2006 Conference Room A, Bldg. 725, BNL DRAFT AGENDA Thursday, June 22 0830 Executive Session to address the charge S. Aronson (25 min) 0855 Welcome S. Aronson (5 min) 0900 Superconducting Magnet Division Status & M. Harrison (45 + 15 min) Issues - mission statement, core competencies, themes, program, problems, etc. 1000 Themes - Nb3Sn, HTS, Direct wind, Accelerator integration, P. Wanderer (20 + 10 min) rapid cycling Core Competencies 1030 Superconducting Materials A. Ghosh (20 + 5 min) 1055 Break 1110 Magnetic Design R. Gupta (20 + 5 min) 1135 Magnet Construction M. Anerella (20 + 5 min) 1200 Magnet Testing G. Ganetis (20 + 5 min)

283

Cool Magnetic Molecules  

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

Cool Magnetic Molecules Print 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 to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to characterize the design of such "molecular coolers." The work targets the synthesis of molecular cluster compounds containing many unpaired electrons ("nanomagnets") for applications involving enhanced magnetic refrigeration at very low temperatures.

284

Cool Magnetic Molecules  

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

Cool Magnetic Molecules Print 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 to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to characterize the design of such "molecular coolers." The work targets the synthesis of molecular cluster compounds containing many unpaired electrons ("nanomagnets") for applications involving enhanced magnetic refrigeration at very low temperatures.

285

Cool Magnetic Molecules  

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

Cool Magnetic Molecules Print 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 to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to characterize the design of such "molecular coolers." The work targets the synthesis of molecular cluster compounds containing many unpaired electrons ("nanomagnets") for applications involving enhanced magnetic refrigeration at very low temperatures.

286

Cool Magnetic Molecules  

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

Cool Magnetic Molecules Print 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 to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to characterize the design of such "molecular coolers." The work targets the synthesis of molecular cluster compounds containing many unpaired electrons ("nanomagnets") for applications involving enhanced magnetic refrigeration at very low temperatures.

287

Cool Magnetic Molecules  

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

Cool Magnetic Molecules Print 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 to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to characterize the design of such "molecular coolers." The work targets the synthesis of molecular cluster compounds containing many unpaired electrons ("nanomagnets") for applications involving enhanced magnetic refrigeration at very low temperatures.

288

Magnet pole tips  

DOE Patents (OSTI)

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.

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

1984-04-24T23:59:59.000Z

289

Magnet pole tips  

DOE Patents (OSTI)

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.

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

1981-11-19T23:59:59.000Z

290

Magnetization of neutron star matter  

E-Print Network (OSTI)

The magnetization of neutron star matter in magnetic fields is studied by employing the FSUGold interaction. It is found that the magnetic susceptibilities of the charged particles (proton, electron and muon) can be larger than that of neutron. The effects of the anomalous magnetic moments (AMM) of each component on the magnetic susceptibility are examined in detail. It is found that the proton and electron AMM affect their respective magnetic susceptibility evidently in strong magnetic fields. In addition, they are the protons instead of the electrons that contribute most significantly to the magnetization of the neutron star matter in a relative weak magnetic field, and the induced magnetic field due to the magnetization can be appear to be very large. Finally, the effect of the density-dependent symmetry energy on the magnetization is discussed.

Dong, Jianmin; Gu, Jianzhong

2013-01-01T23:59:59.000Z

291

Argonne CNM: Electronic and Magnetic Materials and Devices Research  

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

Electronic & Magnetic Materials & Devices Electronic & Magnetic Materials & Devices Group Leader: Saw-Wai Hla The objective of the Electronic and Magnetic Materials and Devices (EMMD) group at the CNM is to discover, understand, and utilize new electron and spin-based materials and phenomena in constrained geometries. Potential benefits include reduced power dissipation, new medical imaging methods and therapies, improved efficiency of data storage by spin current and electrical field-assisted writing, and enhanced energy conversion in photovoltaic devices. Research Activities Understanding complex magnetic order and coupling phenomena: Magnetic nanostructures are prone to complex magnetic ordering phenomena that do not occur in the bulk and that will have strong impact on the further development of functional magnetic nanostructures. Basic science on the influence of demagnetizing effects, geometrical frustration, next-nearest neighbor exchange interactions, unusual anisotropy values, and the spin-orbit interaction at reduced dimensionality are performed with a special focus on temperature-dependent magnetic order-disorder transitions.

292

Magnetic Thin Films and Devices  

Science Conference Proceedings (OSTI)

... metal atoms that form small magnets with Curie ... a toggle operation of the magnetic state of ... A high-frequency probe driving a microwave waveguide ...

2010-10-05T23:59:59.000Z

293

Experiment Hazard Class 9 - Magnets  

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

hazard classification applies to all experiments involving magnets, magnetic fields, and electric fields. Other hazard classifications such as electrical safety and their...

294

Permanent Magnets for Energy Applications  

Science Conference Proceedings (OSTI)

Mar 13, 2012 ... Magnetic Materials for Energy Applications II: Permanent Magnets for ... to 500% in the last 12 months, the most unstable being the price of Dy.

295

Nanostructured Materials for Magnetic Refrigeration  

Science Conference Proceedings (OSTI)

... of Nd-Fe-B Magnets to the Megawatt Scale Generator for the Wind Turbine ... Low Loss, High Power Density Magnetics in Inductor/Transformer Cores for Army ...

296

Search Publications | Superconducting Magnet Division  

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

Rapid Cycling Magnets Helical Magnets HERA upgrade LHC IR Dipoles RHIC Publications Search Publications Selected Cryogenic Data Notebook Proceedings of the 1968 Summer Study on...

297

Bio-Med Variable Field MRI Project | Superconducting Magnet Division  

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

Bio-Med Variable Field MRI Project Bio-Med Variable Field MRI Project One of the Research and Development projects currently underway is the Bio-Med magnet. Destined for use within the solenoidal field of an MRI, it is designed for use where the subject, in this case a rat, must be tracked in order to obtain an image. Typical MRIs require the subject to remain stationary, and a rat will not normally oblige when it is awake. By moving the composite field (MRI Solenoid plus Bio-Med dipole) to track the rat, it is possible to allow the rat some freedom of motion, while still imaging the brain functions. For the rapid movement typical of a rat, the Bio-Med coil magnet must be capable of very rapid changes in field. Superconducting magnets are typically not designed to allow rapid field variations. To do so typically

298

Methods for magnetic resonance analysis using magic angle technique  

DOE Patents (OSTI)

Methods of performing a magnetic resonance analysis of a biological object are disclosed that include placing the object in a main magnetic field (that has a static field direction) and in a radio frequency field; rotating the object at a frequency of less than about 100 Hz around an axis positioned at an angle of about 54.degree.44' relative to the main magnetic static field direction; pulsing the radio frequency to provide a sequence that includes a phase-corrected magic angle turning pulse segment; and collecting data generated by the pulsed radio frequency. In particular embodiments the method includes pulsing the radio frequency to provide at least two of a spatially selective read pulse, a spatially selective phase pulse, and a spatially selective storage pulse. Further disclosed methods provide pulse sequences that provide extended imaging capabilities, such as chemical shift imaging or multiple-voxel data acquisition.

Hu, Jian Zhi (Richland, WA); Wind, Robert A. (Kennewick, WA); Minard, Kevin R. (Kennewick, WA); Majors, Paul D. (Kennewick, WA)

2011-11-22T23:59:59.000Z

299

Magnetically Driven Accretion  

E-Print Network (OSTI)

We carried out 2.5-dimensional resistive magnetohydrodynamic simulations to study the effects of magnetic diffusivity on magnetically driven mass accretion and jet formation. The initial state is a constant angular-momentum torus threaded by large-scale vertical magnetic fields. Since the angular momentum of the torus is extracted due to magnetic braking, the torus medium falls toward the central region. The infalling matter twists the large-scale magnetic fields and drives bipolar jets. We found that (1) when the normalized magnetic diffusivity, ? ? ?/(r0VK0), where VK0 is the Keplerian rotation speed at a reference radius r = r0, is small (? ? 10 ?3), mass accretion and jet formation take place intermittently; (2) when 10 ?3 ? ? ? 10 ?2, the system evolves toward a quasi-steady state; and (3) when ? ? 10 ?2 the accretion/mass 1 outflow rate decreases with ? and approaches 0. The results of these simulations indicate that in the center of a galaxy which has a super-massive ( ? 10 9 M?) black hole, a massive ( ? 10 8 M?) gas torus and magnetic braking provide a mass accretion rate which is sufficient to explain the activity of AGNs when ? ? 5 10?2.

Takuhito Kuwabara; Kazunari Shibata; Takahiro Kudoh

2000-01-01T23:59:59.000Z

300

Multicolor Underwater Imaging Techniques.  

E-Print Network (OSTI)

??Studies were conducted on multispectral polarimetric subtraction imaging techniques for underwater imaging that use a broadband light source. The main objective of this study was (more)

Waggoner, Douglas Scott

2007-01-01T23:59:59.000Z

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


301

Magnetic field generator  

DOE Patents (OSTI)

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.

Krienin, Frank (Shoreham, NY)

1990-01-01T23:59:59.000Z

302

Moment free toroidal magnet  

DOE Patents (OSTI)

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.

Bonanos, Peter (East Brunswick, NJ)

1983-01-01T23:59:59.000Z

303

Permanent magnet energy conversion machine with magnet mounting arrangement  

DOE Patents (OSTI)

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.

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

1999-01-01T23:59:59.000Z

304

Allan Cormack, Computerized Axial Tomography (CAT), and Magnetic Resonance  

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

Allan M. Cormack, Computerized Axial Tomography (CAT) Allan M. Cormack, Computerized Axial Tomography (CAT) and Magnetic Resonance Imaging (MRI) Resources with Additional Information magnetic resonance imaging system Computed axial tomography, commonly known as CAT scanning, was introduced in 1972. During a CAT scan, a large coil of x-ray tubes rotates around the patient's body, taking x-rays from all angles. A computer integrates all of these x-rays into a single, three-dimensional image on a television screen. The data can be saved on the computer. Allan M. Cormack, a high energy physicist at Tufts University, shared the 1979 Nobel Prize in Physiology and Medicine for his key work in developing the methods for CAT scanners. At the time of development, these methods were widely regarded as the most significant advance in medical radiography since the 1895 discovery of x-rays.

305

Magnetic resonance detection: spectroscopy and imaging of lab ...  

Department of Chemistry, University of California, Berkeley, CA, 94720, USA. E-mail: elharel@berkeley.edu; Tel: +1 510 642 2094

306

Magnetic resonance detection: spectroscopy and imaging of lab ...  

ley in Physical Chemistry under the guidance of Alex Pines in the spring of 2008. His research focus at Berkeley was in devel-oping novel detection ...

307

Magnetic resonance imaging with an optical atomic magnetometer  

p rep o larizatio n an d arrivin g at th e d etectio n regio n , as th e p o larizatio n o f w ater relaxes exp o n en tially d u rin g th is p erio d .

308

Lensless Imaging of Magnetic Nanostructures by X-ray Spectro...  

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

F. Schlotter and J. Sthr (SSRL) The unprecedented properties of X-ray free electron lasers (X-FELs) under development world wide will open the door for entirely new classes of...

309

Magnetic resonance imaging (MRI) has opened unparalleled new  

E-Print Network (OSTI)

Approach to Dynamic Energy Minimization in Wireless Transceivers", A. Iranli, H. Fatemi, M. Pedram, Int;17 Optimization problem · Minimize total energy consumption for a link ­ (A) Minimize energy at transmitter ­ (B of SNR and mod. level Vector upper bound on overall Energy consumption #12;20 Some performance results

Shamir, Ron

310

Magnetic resonance imaging of polymer electrolytes and insertion electrodes.  

DOE Green Energy (OSTI)

This program seeks to better define electrode-electrolyte interfaces and solid-state ion transport mechanisms that are a central feature of fuel cells and advanced electrochemical systems. The goal is to develop a new generation of materials with enhanced energy efficiency and reduced tendency toward dendrite or passive film formation at the electrode-electrolyte interface.

Gerald, R. E., II; Klingler, R. J.; Rathke, J. W.

1999-05-19T23:59:59.000Z

311

A numerical approach : broadband technologies for efficient Magnetic Resonance Imaging  

E-Print Network (OSTI)

(cont.) independent receiver coils in parallel or time-axis compression, can be cast as complementary to broadband MRI encoding. This affords broadband non-Fourier MRI with time efficiencies over current fast MRI methods. ...

Mitsouras, Dimitrios, 1976-

2004-01-01T23:59:59.000Z

312

MagneticsLab  

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

Magnetics Laboratory Magnetics Laboratory Manufacturing Technologies The Magnetics Lab provides customers with design, prototyping, packaging solutions and production of unique magnetic and resistive components from millivolts to extremely high voltage (250KV) components. Capabilities * Design review of specification and requirements * Design and develop from sketches, verbal ideas, or circuit design parameters * Coil windings of any size or configuration * Coil diameter from 0.1 to 24 inches * Low temperature and high temperature coils * Precision resistors from 0.1 ohms to 2 megaohms (non-inductive) * Special high voltage transformers (2KV to 250KV) and high voltage loads (38K ohms to 100K ohms and 2KV to 250KV) Resources * Computer Aided Mechanical Design (Solid Works 3D CAD System) for mechanical

313

SUPERCONDUCTING MAGNET DIVISION  

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

MAGNET DIVISION CY 2013 Tier 1 Inspection Schedule Frequency Building Q1 Q2 Q3 Q4 S 902B (Offices) 11713 62013 S 902A (Offices) 11713 62013 Q 902-High Bay Shop 22113 5...

314

Magnetic gripper device  

DOE Patents (OSTI)

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.

Meyer, R.E.

1992-12-31T23:59:59.000Z

315

Computing with magnets  

Science Conference Proceedings (OSTI)

Researchers are finding ways to develop ultra-efficient and nonvolatile computer processors out of nanoscale magnets. A number of obstacles, however, stand in the way of their commercialization.

Gary Anthes

2012-03-01T23:59:59.000Z

316

Superconducting combined function magnets  

SciTech Connect

Superconducting accelerators and storage rings, presently under construction or in the design phase, are based on separate dipole and quadrupole magnets. It is here suggested that a hybrid lattice configuration consisting of dipoles and combined function gradient magnets would: (1) reduce the number of magnet units and their total cost; and (2) increase the filling factor and thus the energy at a given field. Coil cross sections are presented for the example of the Brookhaven Colliding Beam Accelerator. An asymmetric two-layer cable gradient magnet would have transfer functions of 10.42 G/A and 0.628 G cm/sup -1//A versus 15.77 G/A and 2.03 G cm/sup -1//A of the present separate dipoles and quadrupoles.

Hahn, H.; Fernow, R.C.

1983-01-01T23:59:59.000Z

317

Modular tokamak magnetic system  

DOE Patents (OSTI)

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

Yang, Tien-Fang

1986-11-20T23:59:59.000Z

318

AFRD - Superconducting Magnets  

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

Superconducting Magnets Superconducting Magnets Home Organization Diversity Safety Links Gallery/History Updated July 2008 Ever-stronger magnets (which must be cost-effective as well) are a key to building tomorrow's high-energy accelerators and upgrading today's. Our role— not only a leading R&D group but also the administrators of the multi-institutional National Conductor Development Program— to create both evolutionary improvements and paradigm shifts in the application of accelerator magnets, providing innovative technology that enables new science. Improvements in conductor, innovative structures to solve the challenges of high fields and brittle superconductors, and integration of computerized design and analysis tools are key. The performance requirements of modern accelerators continue to press the

319

Magnetic fluorescent lamp  

DOE Patents (OSTI)

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.

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

1983-12-29T23:59:59.000Z

320

Solar Magnetic Feature Detection and Tracking for Space Weather Monitoring  

E-Print Network (OSTI)

We present an automated system for detecting, tracking, and cataloging emerging active regions throughout their evolution and decay using SOHO Michelson Doppler Interferometer (MDI) magnetograms. The SolarMonitor Active Region Tracking (SMART) algorithm relies on consecutive image differencing to remove both quiet-Sun and transient magnetic features, and region-growing techniques to group flux concentrations into classifiable features. We determine magnetic properties such as region size, total flux, flux imbalance, flux emergence rate, Schrijver's R-value, R* (a modified version of R), and Falconer's measurement of non-potentiality. A persistence algorithm is used to associate developed active regions with emerging flux regions in previous measurements, and to track regions beyond the limb through multiple solar rotations. We find that the total number and area of magnetic regions on disk vary with the sunspot cycle. While sunspot numbers are a proxy to the solar magnetic field, SMART offers a direct diagnos...

Higgins, Paul A; McAteer, R T James; Bloomfield, D Shaun; 10.1016/j.asr.2010.06.024

2010-01-01T23:59:59.000Z

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


321

LABORATORY VI ELECTRICITY FROM MAGNETISM  

E-Print Network (OSTI)

the magnetic field and its effect on moving charges. You also saw how electric currents could create magnetic the magnetic flux through a coil of wire to produce an electric current. You will investigate the current are necessary for a magnetic field to produce an electric current. · Determine the direction of a current

Minnesota, University of

322

Electronic, Magnetic & Photonic Materials Division  

Science Conference Proceedings (OSTI)

... Committee Energy Conversion and Storage Committee Magnetic Materials Committee Nanomaterials Committee Thin Films and Interfaces Committee.

323

Freely oriented portable superconducting magnet  

SciTech Connect

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.

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

2010-01-12T23:59:59.000Z

324

Mining partially annotated images  

Science Conference Proceedings (OSTI)

In this paper, we study the problem of mining partially annotated images. We first define what the problem of mining partially annotated images is, and argue that in many real-world applications annotated images are typically partially annotated and ... Keywords: image annotation completion and prediction, partially annotated training set, semi-supervised learning

Zhongang Qi; Ming Yang; Zhongfei (Mark) Zhang; Zhengyou Zhang

2011-08-01T23:59:59.000Z

325

MAGNETIC NEUTRON SCATTERING  

SciTech Connect

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.

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

2004-07-30T23:59:59.000Z

326

RHIC Project | Superconducting Magnet Division  

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

RHIC Project RHIC Project The Superconducting Magnet Division supplied 1740 magnetic elements, in 888 cryostats, for the RHIC facility at BNL. Of these, 780 magnetic elements were manufactured by Northrop-Grumman (Bethpage, NY) and 360 were made by Everson Electric (Bethlehem, PA). The magnets made in industry used designs developed at BNL. The first cooldown of the magnets for the RHIC engineering run was in 1999. Since then, the magnets have operated very reliably. arc dipole coil and yoke Arc dipole coil and yoke, with magnetic flux lines The magnets provide modest field (3.45 Teslas in the arc dipoles) in a cost-effective design. Key features in the principal bending and focusing magnets include the use of NbTi Rutherford cable, a single-layer coil, and cold iron as both yoke and collar. The magnets operate in forced-flow

327

Ground Magnetics | Open Energy Information  

Open Energy Info (EERE)

Ground Magnetics Ground Magnetics Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Ground Magnetics Details Activities (15) Areas (12) Regions (0) NEPA(1) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Magnetic Techniques Parent Exploration Technique: Magnetic Techniques Information Provided by Technique Lithology: Presence of magnetic minerals such as magnetite. Stratigraphic/Structural: Mapping of basement structures, horst blocks, fault systems, fracture zones, dykes and intrusions. Hydrological: The circulation of hydrothermal fluid may impact the magnetic susceptibility of rocks. Thermal: Rocks lose their magnetic properties at the Curie temperature (580° C for magnetite) [1] and, upon cooling, remagnetize in the present magnetic field orientation. The Curie point depth in the subsurface may be determined in a magnetic survey to provide information about hydrothermal activity in a region.

328

Seismic Imaging and Monitoring  

SciTech Connect

I give an overview of LANL's capability in seismic imaging and monitoring. I present some seismic imaging and monitoring results, including imaging of complex structures, subsalt imaging of Gulf of Mexico, fault/fracture zone imaging for geothermal exploration at the Jemez pueblo, time-lapse imaging of a walkway vertical seismic profiling data for monitoring CO{sub 2} inject at SACROC, and microseismic event locations for monitoring CO{sub 2} injection at Aneth. These examples demonstrate LANL's high-resolution and high-fidelity seismic imaging and monitoring capabilities.

Huang, Lianjie [Los Alamos National Laboratory

2012-07-09T23:59:59.000Z

329

Seismic Imaging and Monitoring  

SciTech Connect

I give an overview of LANL's capability in seismic imaging and monitoring. I present some seismic imaging and monitoring results, including imaging of complex structures, subsalt imaging of Gulf of Mexico, fault/fracture zone imaging for geothermal exploration at the Jemez pueblo, time-lapse imaging of a walkway vertical seismic profiling data for monitoring CO{sub 2} inject at SACROC, and microseismic event locations for monitoring CO{sub 2} injection at Aneth. These examples demonstrate LANL's high-resolution and high-fidelity seismic imaging and monitoring capabilities.

Huang, Lianjie [Los Alamos National Laboratory

2012-07-09T23:59:59.000Z

330

Manhattan Project: Trinity Images  

Office of Scientific and Technical Information (OSTI)

IMAGES IMAGES Trinity Test Site (July 16, 1945) Resources > Photo Gallery The first 0.11 seconds of the Nuclear Age These seven photographs of the Trinity test were taken by time-lapse cameras. The last is 109 milliseconds, or 0.109 seconds, after detonation. Scroll down to view each individual image. The photographs are courtesy the Los Alamos National Laboratory, via the Federation of American Scientists web site. The animation is original to the Office of History and Heritage Resources. The dawn of the Nuclear Age (Trinity image #1) The dawn of the Nuclear Age Trinity image #2 Trinity image #3 Trinity image #4 Trinity image #5 Trinity, 0.09 seconds after detonation (Trinity image #6) Trinity, 0.09 seconds after detonation Trinity, 0.11 seconds after detonation (Trinity image #7)

331

Web accessible image similarity measurements  

Science Conference Proceedings (OSTI)

Web accessible image similarity measurements. Background: There ... messages). Web Access to Image Similarity Measurements. ...

2013-04-16T23:59:59.000Z

332

MAGNETIC FIELD STRUCTURES TRIGGERING SOLAR FLARES AND CORONAL MASS EJECTIONS  

SciTech Connect

Solar flares and coronal mass ejections, the most catastrophic eruptions in our solar system, have been known to affect terrestrial environments and infrastructure. However, because their triggering mechanism is still not sufficiently understood, our capacity to predict the occurrence of solar eruptions and to forecast space weather is substantially hindered. Even though various models have been proposed to determine the onset of solar eruptions, the types of magnetic structures capable of triggering these eruptions are still unclear. In this study, we solved this problem by systematically surveying the nonlinear dynamics caused by a wide variety of magnetic structures in terms of three-dimensional magnetohydrodynamic simulations. As a result, we determined that two different types of small magnetic structures favor the onset of solar eruptions. These structures, which should appear near the magnetic polarity inversion line (PIL), include magnetic fluxes reversed to the potential component or the nonpotential component of major field on the PIL. In addition, we analyzed two large flares, the X-class flare on 2006 December 13 and the M-class flare on 2011 February 13, using imaging data provided by the Hinode satellite, and we demonstrated that they conform to the simulation predictions. These results suggest that forecasting of solar eruptions is possible with sophisticated observation of a solar magnetic field, although the lead time must be limited by the timescale of changes in the small magnetic structures.

Kusano, K.; Bamba, Y.; Yamamoto, T. T. [Solar-Terrestrial Environment Laboratory, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601 (Japan); Iida, Y.; Toriumi, S. [Department of Earth and Planetary Science, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Asai, A., E-mail: kusano@nagoya-u.jp [Unit of Synergetic Studies for Space, Kyoto University, 17 Kitakazan Ohmine-cho, Yamashina-ku, Kyoto 607-8471 (Japan)

2012-11-20T23:59:59.000Z

333

GSI Rapid Cycling Magnets Project | Superconducting Magnet Division  

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

GSI Rapid Cycling Magnets Project GSI Rapid Cycling Magnets Project While superconducting magnets easily achieve higher magnetic fields at lower cost than conventional electromagnets, it is very difficult to ramp superconducting magnets very quickly. But exactly that is needed at the planned new facility of GSI, the Gesellschaft für Schwerionenforschung (Institute for Heavy Ion Research), in Darmstadt, Germany. In the magnets of the SIS 200 ring, one of the components of the new facility, the magnetic field must be ramped from 0.5 Tesla to 4 Tesla at a rate of 1 Tesla per second. This ramp rate is almost 25 times faster than the ramp rate of the Relativistic Heavy Ion Collider (RHIC) magnets at Brookhaven National Lab (BNL), which ramp at a rate of 0.042 Tesla per second. While the SIS 200 magnets also require a slightly higher field strength than the

334

Image registration method for medical image sequences  

DOE Patents (OSTI)

Image registration of low contrast image sequences is provided. In one aspect, a desired region of an image is automatically segmented and only the desired region is registered. Active contours and adaptive thresholding of intensity or edge information may be used to segment the desired regions. A transform function is defined to register the segmented region, and sub-pixel information may be determined using one or more interpolation methods.

Gee, Timothy F.; Goddard, James S.

2013-03-26T23:59:59.000Z

335

Switching a magnetic vortex by interlayer coupling in epitaxially grown Co/Cu/Py/Cu(001) trilayer disks  

SciTech Connect

Epitaxial Py/Cu/Co/Cu(001) trilayers were patterned into micron sized disks and imaged using element-specific photoemission electron microscopy. By varying the Cu spacer layer thickness, we study how the coupling between the two magnetic layers influences the formation of magnetic vortex states. We find that while the Py and Co disks form magnetic vortex domains when the interlayer coupling is ferromagnetic, the magnetic vortex domains of the Py and Co disks break into anti-parallel aligned multidomains when the interlayer coupling is antiferromagnetic. We explain this result in terms of magnetic flux closure between the Py and Co layers for the antiferromagnetic coupling case.

Wu, J.; Carlton, D.; Oelker, E.; Park, J. S.; Jin, E.; Arenholz, E.; Scholl, A.; Hwang, C.; Bokor, J.; Qiu, Z Q

2010-07-16T23:59:59.000Z

336

R&D ERL: Magnetic measurements of the ERL magnets  

SciTech Connect

The magnet system of ERL consists of G5 solenoids, 6Q12 quadrupoles with 0.58 T/m gradient, 3D60 dipoles with 0.4 T central field, 15 and 30 degree Z-bend injection line dipole/quadrupole combined function magnets, and extraction line magnets. More details about the magnets can be found in a report by G. Mahler. Field quality in all the 6Q12 quadrupoles, 3D60 dipoles and the injection line magnets has been measured with either a rotating coil, or a Hall probe mapper. This report presents the results of these magnetic measurements.

Jain, A.

2010-08-01T23:59:59.000Z

337

Magnets and Power Supplies  

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

Bibliography Up: APS Storage Ring Parameters Previous: Longitudinal Bibliography Up: APS Storage Ring Parameters Previous: Longitudinal bunch profile and Magnets and Power Supplies Dipole Magnets and Power Supplies Value Dipole Number 80+1 No. of power supplies 1 Magnetic length 3.06 m Core length 3.00 m Bending radius 38.9611 m Power supply limit 500.0 A Field at 7 GeV 0.599 T Dipole trim coils Number 80+1 No. of power supplies 80 Magnetic length 3.06 m Core length 3.00 m Power supply limit 20.0 A Maximum field 0.04 T Horizontal Correction Dipoles Number 317 No. of power supplies 317 Magnetic length 0.160 m Core length 0.07 m Power supply limit 150.0 A Maximum field 0.16 T Max. deflection at 7 GeV 1.1 mrad Vertical Corrector Dipoles Number 317 No. of power supplies 317

338

Active magnetic regenerator  

DOE Patents (OSTI)

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)

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

1981-01-27T23:59:59.000Z

339

Magnetic reconnection launcher  

DOE Patents (OSTI)

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.

Cowan, Maynard (Albuquerque, NM)

1989-01-01T23:59:59.000Z

340

Magnetic Techniques | Open Energy Information  

Open Energy Info (EERE)

Magnetic Techniques Magnetic Techniques Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Magnetic Techniques Details Activities (0) Areas (0) Regions (0) NEPA(1) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Magnetic Techniques Parent Exploration Technique: Geophysical Techniques Information Provided by Technique Lithology: Presence of magnetic minerals such as magnetite. Stratigraphic/Structural: Mapping of basement structures, horst blocks, fault systems, fracture zones, dykes and intrusions. Hydrological: The circulation of hydrothermal fluid may impact the magnetic susceptibility of rocks. Thermal: Rocks lose their magnetic properties at the Curie temperature (580° C for magnetite) [1] and, upon cooling, remagnetize in the present magnetic field orientation. The Curie point depth in the subsurface may be determined in a magnetic survey to provide information about hydrothermal activity in a region.

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


341

Superconducting magnetic coil  

DOE Patents (OSTI)

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.

Aized, D.; Schwall, R.E.

1999-06-22T23:59:59.000Z

342

Purely magnetic spacetimes  

E-Print Network (OSTI)

Spacetimes in which the electric part of the Weyl tensor vanishes (relative to some timelike unit vector field) are said to be purely magnetic. Examples of purely magnetic spacetimes are known and are relatively easy to construct, if no restrictions are placed on the energy-momentum tensor. However it has long been conjectured that purely magnetic vacuum spacetimes (with or without a cosmological constant) do not exist. The history of this conjecture is reviewed and some advances made in the last year are described briefly. A generalisation of this conjecture first suggested for type D vacuum spacetimes by Ferrando and Saez is stated and proved in a number of special cases. Finally an approach to a general proof of the conjecture is described using the Newman-Penrose formalism based on a canonical null tetrad of the Weyl tensor.

Alan Barnes

2004-01-15T23:59:59.000Z

343

Simple microwave field imaging technique using hot atomic vapor cells  

E-Print Network (OSTI)

We demonstrate a simple technique for microwave field imaging using alkali atoms in a vapor cell. The microwave field to be measured drives Rabi oscillations on atomic hyperfine transitions, which are detected in a spatially resolved way using a laser beam and a CCD camera. Our vapor cell geometry enables single-shot recording of two-dimensional microwave field images with 350 {\\mu}m spatial resolution. Using microfabricated vapor cell arrays, a resolution of a few micrometers seems feasible. All vector components of the microwave magnetic field can be imaged. Our apparatus is simple and compact and does not require cryogenics or ultra-high vacuum.

Bhi, Pascal

2012-01-01T23:59:59.000Z

344

Simple microwave field imaging technique using hot atomic vapor cells  

E-Print Network (OSTI)

We demonstrate a simple technique for microwave field imaging using alkali atoms in a vapor cell. The microwave field to be measured drives Rabi oscillations on atomic hyperfine transitions, which are detected in a spatially resolved way using a laser beam and a camera. Our vapor cell geometry enables single-shot recording of two-dimensional microwave field images with 350 {\\mu}m spatial resolution. Using microfabricated vapor cell arrays, a resolution of a few micrometers seems feasible. All vector components of the microwave magnetic field can be imaged. Our apparatus is simple and compact and does not require cryogenics or ultra-high vacuum.

Pascal Bhi; Philipp Treutlein

2012-07-20T23:59:59.000Z

345

Observation and implications of magnetic domains in lateral spin valves  

Science Conference Proceedings (OSTI)

Co/Cu/Co lateral spin valves (LSV), with Co being the topmost layer, are in situ prepared and measured under ultrahigh vacuum conditions. The clean process yields a non-local spin signal of 0.9 m{Omega}. Scanning electron microscopy with polarization analysis (SEMPA) reveals domain structures in both magnetic electrodes that depend on the LSV dimensions. The spin signal correlates to SEMPA images as well as the anisotropic magnetoresistance of both Co magnets, revealing a strong impact of multi-domain states on the spin signal.

Mennig, J.; Matthes, F.; Buergler, D. E.; Schneider, C. M. [Peter Gruenberg Institute, Electronic Properties (PGI-6) and Juelich-Aachen Research Alliance, Fundamentals of Future Information Technology (JARA-FIT), Forschungszentrum Juelich GmbH, Juelich D-52425 (Germany)

2012-04-01T23:59:59.000Z

346

Requirements of Magnetic Materials for Current Technological ...  

Science Conference Proceedings (OSTI)

Mar 3, 2011 ... Magnetic Materials for Energy Applications: Requirements of Magnetic ... Hard magnetic materials play a significant role in many green...

347

Experiment #7: Magnetic Deflection of Beta Rays  

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

of magnetism. Materials Geiger counter Wooden block (to hold the source) Aluminum shield with hole (for Geiger counter) Two cow magnets Magnet holders Sr-90 (beta source)...

348

The solar magnetic field  

E-Print Network (OSTI)

The magnetic field of the Sun is the underlying cause of the many diverse phenomena combined under the heading of solar activity. Here we describe the magnetic field as it threads its way from the bottom of the convection zone, where it is built up by the solar dynamo, to the solar surface, where it manifests itself in the form of sunspots and faculae, and beyond into the outer solar atmosphere and, finally, into the heliosphere. On the way it, transports energy from the surface and the subsurface layers into the solar corona, where it heats the gas and accelerates the solar wind.

Solanki, Sami K; Schssler, Manfred; 10.1088/0034-4885/69/3/R02

2010-01-01T23:59:59.000Z

349

Ultra-low field nuclear magnetic resonance and magnetic resonance imaging to discriminate and identify materials  

DOE Patents (OSTI)

Method comprising obtaining an NMR measurement from a sample wherein an ultra-low field NMR system probes the sample and produces the NMR measurement and wherein a sampling temperature, prepolarizing field, and measurement field are known; detecting the NMR measurement by means of inductive coils; analyzing the NMR measurement to obtain at least one measurement feature wherein the measurement feature comprises T1, T2, T1.rho., or the frequency dependence thereof; and, searching for the at least one measurement feature within a database comprising NMR reference data for at least one material to determine if the sample comprises a material of interest.

Matlashov, Andrei Nikolaevich; Urbaitis, Algis V.; Savukov, Igor Mykhaylovich; Espy, Michelle A.; Volegov, Petr Lvovich; Kraus, Jr., Robert Henry

2013-03-05T23:59:59.000Z

350

Magnetic structure of Loihi Seamount, an active hotspot volcano in the Hawaiian Island chain  

E-Print Network (OSTI)

The use of geophysical techniques to image the interiors of active volcanoes can provide a better understanding of their structure and plumbing. The need for such information is especially critical for undersea volcanoes, whose environment makes them difficult to investigate. Because undersea volcanoes are made up of highly magnetic basaltic rock, it is possible to use variations in the magnetic field to explore the internal structure of such edifices. This study combines magnetic survey data from 12 research cruises to make a magnetic anomaly map of volcanically active Loihi, located in the Hawaiian Island chain. NRM intensities and susceptibility measurements were measured from recovered rock samples and suggest that magnetic properties of Loihi are widely varied (NRM intensities range from 1-157 A/m and susceptibilities from 1.26 x 10-3 to 3.62 x 10-2 S.I.). The average NRM intensity is 26 A/m. The size and strength of magnetic source bodies were determined by using various modeling techniques. A strongly magnetized shield can explain most of the anomaly with a large nonmagnetic zone inside, beneath the summit. Prominent magnetic highs are located along Loihi's north and south rift zone dikes and modeling solutions suggest strongly magnetized source bodies in these areas as well as a thin, magnetic layer atop the nonmagnetic zone. The strong magnetic anomalies found along the volcano's rift zones cannot be readily attributed to recent lava flows at the surface. Instead, the source bodies must continue several kilometers in depth to give reasonable magnetization values and are interpreted as dike intrusions. Nonmagnetic anomalies at the summit and south of the summit suggest the presence of a magma system. The model solution suggests Loihi is an inhomogeneously magnetized seamount with highly magnetic dike intrusions along the rift zones with a nonmagnetic body at its center overlain with a magnetic layer.

Lamarche, Amy J.

2003-12-01T23:59:59.000Z

351

Fast superconducting magnetic field switch  

DOE Patents (OSTI)

The superconducting magnetic switch or fast kicker magnet is employed with an 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 than 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. Magnetic switches and particularly fast kicker magnets are used in the accelerator industry to quickly deflect particle beams into and out of various transport lines, storage rings, dumps, and specifically to differentially route individual bunches of particles from a train of bunches which are injected or ejected from a given ring.

Goren, Y.; Mahale, N.K.

1995-12-31T23:59:59.000Z

352

Estimation theoretical image restoration  

E-Print Network (OSTI)

In this thesis, we have developed an extensive study to evaluate image restoration from a single image, colored or monochromatic. Using a mixture of Gaussian and Poisson noise process, we derived an objective function to ...

Dolne, Jean J

2008-01-01T23:59:59.000Z

353

Synthetic stereoscopic panoramic images  

Science Conference Proceedings (OSTI)

Presented here is a discussion of the techniques required to create stereoscopic panoramic images. Such images allow interactive exploration of 3D environments with stereoscopic depth cues. If projected in a surround display environment they can engage ...

Paul Bourke

2006-10-01T23:59:59.000Z

354

Nuclear Imaging instrumentation  

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

Nuclear Imaging instrumentation Advances in gamma-ray detection and imaging have increased the pace of discovery in a broad cross-section of the sciences ranging from nuclear...

355

Spectrographic imaging system  

DOE Patents (OSTI)

An imaging system for providing spectrographically resolved images. The system incorporates a one-dimensional spatial encoding mask which enables an image to be projected onto a two-dimensional image detector after spectral dispersion of the image. The dimension of the image which is lost due to spectral dispersion on the two-dimensional detector is recovered through employing a reverse transform based on presenting a multiplicity of different spatial encoding patterns to the image. The system is especially adapted for detecting Raman scattering of monochromatic light transmitted through or reflected from physical samples. Preferably, spatial encoding is achieved through the use of Hadamard mask which selectively transmits or blocks portions of the image from the sample being evaluated.

Morris, Michael D. (Ann Arbor, MI); Treado, Patrick J. (Ann Arbor, MI)

1991-01-01T23:59:59.000Z

356

NIST Image Gallery: Search  

Science Conference Proceedings (OSTI)

... Search Tips - Search index includes image titles, descriptions, other text fields - Searches are case-insensitive - Keyword2 is optional. ...

357

Cell Image Visualization  

Science Conference Proceedings (OSTI)

... Biological cell image analysis projects include methods to measure cell segmentation accuracy and new segmentation methods to track live cells. ...

2011-06-17T23:59:59.000Z

358

Video image position determination  

DOE Patents (OSTI)

An optical beam position controller in which a video camera captures an image of the beam in its video frames, and conveys those images to a processing board which calculates the centroid coordinates for the image. The image coordinates are used by motor controllers and stepper motors to position the beam in a predetermined alignment. In one embodiment, system noise, used in conjunction with Bernoulli trials, yields higher resolution centroid coordinates.

Christensen, Wynn (Los Alamos, NM); Anderson, Forrest L. (Bernalillo, NM); Kortegaard, Birchard L. (Los Alamos, NM)

1991-01-01T23:59:59.000Z

359

Imaging with Scattered Neutrons  

E-Print Network (OSTI)

We describe a novel experimental technique for neutron imaging with scattered neutrons. These scattered neutrons are of interest for condensed matter physics, because they permit to reveal the local distribution of incoherent and coherent scattering within a sample. In contrast to standard attenuation based imaging, scattered neutron imaging distinguishes between the scattering cross section and the total attenuation cross section including absorption. First successful low-noise millimeter-resolution images by scattered neutron radiography and tomography are presented.

H. Ballhausen; H. Abele; R. Gaehler; M. Trapp; A. Van Overberghe

2006-10-30T23:59:59.000Z

360

Moving Magnet Series with  

E-Print Network (OSTI)

material allows for exceptional flux densi- ties in the air gap. The intense magnetic field strengthV/Degree/Second, +/-10% Current, RMS 2.3 2.4 4.1 3.9 A, Maximum Current, Peak 6 8 20 20 A, Maximum Small Angle Step

Kleinfeld, David

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


361

Rotary magnetic heat pump  

DOE Patents (OSTI)

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.

Kirol, Lance D. (Shelly, ID)

1988-01-01T23:59:59.000Z

362

National Magnetic Anomaly Map  

DOE Green Energy (OSTI)

A record of the conclusions of a three-day meeting and workshop of the Committee for a National Magnetic Anomaly Map held in February 1976 is presented. The purpose of he workshop was to prepare a statement of the benefits, objectives, specifications, and requirements of a NMAM and establish a working plan for producing the map. (ACR)

Not Available

1976-01-01T23:59:59.000Z

363

Rotary magnetic heat pump  

DOE Patents (OSTI)

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.

Kirol, L.D.

1987-02-11T23:59:59.000Z

364

Magnetic resonance apparatus  

SciTech Connect

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.

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

1982-01-01T23:59:59.000Z

365

Permanent Magnet Materials  

Science Conference Proceedings (OSTI)

Table 4 Applications of permanent magnet materials...material Primary reason for selection Alternative material Condition or reason favoring selection of alternative material Aircraft magnetos, military or civilian SmCo Maximum energy per unit volume Cast Alnico 5 Availability or cost restraint Alternators SmCo Compactness and reliability Ferrite...

366

Permanent Magnet Materials  

Science Conference Proceedings (OSTI)

Table 4   Applications of permanent magnet materials...material Primary reason for selection Alternative material Condition or reason favoring selection of alternative material Aircraft magnetos, military or civilian SmCo Maximum energy per unit volume Cast Alnico 5 Availability or cost restraint Alternators SmCo Compactness and reliability Ferrite...

367

Magnetic refrigeration apparatus and method  

SciTech Connect

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.

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

1984-01-01T23:59:59.000Z

368

Document Imaging | Department of Energy  

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

Document Imaging Document Imaging Employee Services Cafeterias Conferencing and Special Events Copy Services Document Imaging Exchange Visitors Program Facility Operations Food...

369

Medical imaging systems  

Science Conference Proceedings (OSTI)

A medical imaging system provides simultaneous rendering of visible light and diagnostic or functional images. The system may be portable, and may include adapters for connecting various light sources and cameras in open surgical environments or laparascopic or endoscopic environments. A user interface provides control over the functionality of the integrated imaging system. In one embodiment, the system provides a tool for surgical pathology.

Frangioni, John V

2013-06-25T23:59:59.000Z

370

Acoustic Imaging Suite  

INLs acoustic imaging technology improves methods of capturing moving images of a specified object by using a photorefractive effect to produce a full-field image of the object without using a probe to perform a full scan of the object. INL ...

371

Diagnostic Imaging Emergency Medicine  

E-Print Network (OSTI)

UC Davis Veterinary Diagnostic Imaging Symposium Emergency Medicine May 15, 2011 Gladys Valley Hall devoted to triage, assessment, and imaging diagnostics in emergency medicine. Speakers in this year's symposium include specialists in diagnostic imaging, and emergency and critical care. Sunday May 15, 2011 8

Hammock, Bruce D.

372

Magnetic Devices and Nanostructures (2005)  

Science Conference Proceedings (OSTI)

... Molecular nanomagnets, which are the smallest well defined magnetic ... moment of a specimen as microwave stimulation causes resonance at ...

2010-10-13T23:59:59.000Z

373

Evolution of twisted magnetic fields  

SciTech Connect

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.

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

1985-02-01T23:59:59.000Z

374

ASYMMETRIC MAGNETIZATION REVERSAL IN EXCHANGE ...  

Science Conference Proceedings (OSTI)

... Read-write heads used with magnetically stored data are based on giant magnetoresistance (GMR) sensors. These sensors ...

2001-02-27T23:59:59.000Z

375

Magnetic reconnection launcher  

DOE Patents (OSTI)

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.

Cowan, M.

1987-04-06T23:59:59.000Z

376

Magnetic Helicity in Sphaleron Debris  

E-Print Network (OSTI)

We develop an analytical technique to evaluate the magnetic helicity in the debris from sphaleron decay. We show that baryon number production leads to left-handed magnetic fields, and that the magnetic helicity is conserved at late times. Our analysis explicitly demonstrates the connection between sphaleron-mediated cosmic baryogenesis and cosmic magnetogenesis.

Yi-Zen Chu; James B. Dent; Tanmay Vachaspati

2011-05-18T23:59:59.000Z

377

Low-temperature magnetic refrigerator  

SciTech Connect

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.

Barclay, John A. (Los Alamos, NM)

1985-01-01T23:59:59.000Z

378

Low-temperature magnetic refrigerator  

DOE Patents (OSTI)

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.

Barclay, J.A.

1983-05-26T23:59:59.000Z

379

Optical imaging correlates with magnetic resonance imaging breast density and reveals composition changes during neoadjuvant chemotherapy  

E-Print Network (OSTI)

chemotherapy. Breast Cancer Research 2013 15:R14. SubmitSullivan et al. Breast Cancer Research 2013, 15:R14 http://Sullivan et al. Breast Cancer Research 2013, 15:R14 http://

2013-01-01T23:59:59.000Z

380

HELICAL LENGTHS OF MAGNETIC CLOUDS FROM THE MAGNETIC FLUX CONSERVATION  

SciTech Connect

We estimate axial lengths of helical parts in magnetic clouds (MCs) at 1 AU from the magnetic flux (magnetic helicity) conservation between solar active regions (ARs) and MCs with the event list of Leamon et al. Namely, considering poloidal magnetic flux (PHI{sub P}) conservation between MCs and ARs, we estimated L{sub h} in MCs, where L{sub h} is the axial length of an MC where poloidal magnetic flux and magnetic twist exist. It is found that L{sub h} is 0.01-1.25 AU in the MCs. If the cylinder flux rope picture is assumed, this result leads to a possible new picture of the cylinder model whose helical structure (namely, poloidal magnetic flux) localizes in a part of a MC.

Yamamoto, Tetsuya T. [Solar-Terrestrial Environment Laboratory, Nagoya University, Chikusa, Nagoya, 464-8601 (Japan); Kataoka, R. [Interactive Research Center of Science, Tokyo Institute of Technology, Meguro, 152-8550 (Japan); Inoue, S., E-mail: tyamamot@stelab.nagoya-u.ac.j [National Institute of Information and Communications Technology, Koganei, 184-8795 (Japan)

2010-02-10T23:59:59.000Z

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


381

Magnetic behaviour of europium epitaxial thin films  

Science Conference Proceedings (OSTI)

... Magnetic behaviour of europium epitaxial thin films. Philippe Mangin, University of Nancy and NCNR. We present the magnetic ...

382

Argonne CNM News: Bifunctional Plasmonic/Magnetic Nanoparticles  

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

Bifunctional Plasmonic/Magnetic Nanoparticles Bifunctional Plasmonic/Magnetic Nanoparticles Mark Holt (Argonne Center for Nanoscale Materials) examines a sample in the Hard X-Ray Nanoprobe Evolutional pathway from iron particle seeds with thin layers of amorphous iron oxide coating to hybrid nanoparticles composed of solid Ag nanodomains and hollow Fe3O4 nanoshells. Transmission electron microscopy (TEM) images (false colorized) and corresponding schematic illustration (silver: yellow, iron oxide: blue, iron core: black) of the hybrid particles at different stages along the reaction are highlighted on the edge. The TEM image at the center highlights Ag-Fe3O4 hybrid nanoparticles in which Ag and Fe3O4 are false colorized in orange yellow and blue, respectively. TEM analysis was done at Argonne's Electron Microscopy Center

383

Shape-based image retrieval applied to trademark images  

Science Conference Proceedings (OSTI)

In this chapter, we propose a new shape-based, query-by-example, image database retrieval method that is able to match a query image to one of the images in the database, based on a whole or partial match. The proposed method has two key components: ... Keywords: image databases, shape analysis, shape representation, shape-based image retrieval, trademark image retrieval

Ossama El Badawy; Mohamed Kamel

2004-01-01T23:59:59.000Z

384

SNAP Image Gallery  

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

Images Images Cutaway image of SNAP A cutaway illustration of SNAP showing some of the interior optics. Cutaway image of SNAP A computer generated cutaway illustration of SNAP Cutaway image of SNAP's primary mirror A computer generated cutaway illustration of SNAP's primary mirror image of SNAP spacecraft A computer generated illustration of the SNAP spacecraft computer generated image of SNAP A computer generated illustration of SNAP Before-and-after pictures (and Hubble Space Telescope picture) of a high-redshift supernovae discovered by the Supernova Cosmology Project in March, 1998. Before-and-after pictures (and Hubble Space Telescope picture) of a high-redshift supernovae discovered in March, 1998. This observaton showed that the expansion of the universe was accelerarting. Credit: High Redshift Supernova Search Supernova Cosmology Project

385

Zoomed Functional Imaging in the Human Brain at 7 Tesla with Simultaneous High Spatial and High Temporal Resolution  

E-Print Network (OSTI)

Zoomed Functional Imaging in the Human Brain at 7 Tesla with Simultaneous High Spatial and High and is mainly limited by sensitivity. Here, signal-to-noise gains at high magnetic fields (7 Tesla

386

OpenEI Community - images  

Open Energy Info (EERE)

Image upload with broken thumbnail image http:en.openei.orgcommunitydiscussionimage-upload-broken-thumbnail-image

OpenEI users can upload images to the wiki by typing a new...

387

Similarity Retrieval of Trademark Images  

Science Conference Proceedings (OSTI)

The Artisan system retrieves abstract trademark images by shape similarity. It analyzes each image to characterize key shape components, grouping image regions into families that potentially mirror human image perception, and then derives characteristic ...

John P. Eakins; Jago M. Boardman; Margaret E. Graham

1998-04-01T23:59:59.000Z

388

Magnetic Edge States in Graphene  

E-Print Network (OSTI)

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

Gabriela Murguia

2010-08-29T23:59:59.000Z

389

Towards Understanding Electronic Switching in Magnets | U.S. DOE Office of  

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

Understanding Electronic Switching in Magnets Understanding Electronic Switching in Magnets Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic Energy Sciences Advisory Committee (BESAC) News & Resources Contact Information Basic Energy Sciences U.S. Department of Energy SC-22/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3081 F: (301) 903-6594 E: sc.bes@science.doe.gov More Information » September 2013 Towards Understanding Electronic Switching in Magnets Researchers have invented a new x-ray imaging technique that could reveal key atomic-scale properties in ferroelectric magnetic materials. Print Text Size: A A A Subscribe FeedbackShare Page Click to enlarge photo. Enlarge Photo Image courtesy of Argonne National Laboratory

390

Evidence of small-scale magnetic concentrations dragged by vortex motion of solar photospheric plasma  

E-Print Network (OSTI)

Vortex-type motions have been measured by tracking bright points in high-resolution observations of the solar photosphere. These small-scale motions are thought to be determinant in the evolution of magnetic footpoints and their interaction with plasma and therefore likely to play a role in heating the upper solar atmosphere by twisting magnetic flux tubes. We report the observation of magnetic concentrations being dragged towards the center of a convective vortex motion in the solar photosphere from high-resolution ground-based and space-borne data. We describe this event by analyzing a series of images at different solar atmospheric layers. By computing horizontal proper motions, we detect a vortex whose center appears to be the draining point for the magnetic concentrations detected in magnetograms and well-correlated with the locations of bright points seen in G-band and CN images.

Balmaceda, L; Palacios, J; Cabello, I; Domingo, V

2010-01-01T23:59:59.000Z

391

Magnetized Turbulent Dynamo in Protogalaxies  

Science Conference Proceedings (OSTI)

The prevailing theory for the origin of cosmic magnetic fields is that they have been amplified to their present values by the turbulent dynamo inductive action in the protogalactic and galactic medium. Up to now, in calculation of the turbulent dynamo, it has been customary to assume that there is no back reaction of the magnetic field on the turbulence, as long as the magnetic energy is less than the turbulent kinetic energy. This assumption leads to the kinematic dynamo theory. However, the applicability of this theory to protogalaxies is rather limited. The reason is that in protogalaxies the temperature is very high, and the viscosity is dominated by magnetized ions. As the magnetic field strength grows in time, the ion cyclotron time becomes shorter than the ion collision time, and the plasma becomes strongly magnetized. As a result, the ion viscosity becomes the Braginskii viscosity. Thus, in protogalaxies the back reaction sets in much earlier, at field strengths much lower than those which correspond to field-turbulence energy equipartition, and the turbulent dynamo becomes what we call the magnetized turbulent dynamo. In this paper we lay the theoretical groundwork for the magnetized turbulent dynamo. In particular, we predict that the magnetic energy growth rate in the magnetized dynamo theory is up to ten times larger than that in the kinematic dynamo theory. We also briefly discuss how the Braginskii viscosity can aid the development of the inverse cascade of magnetic energy after the energy equipartition is reached.

Leonid Malyshkin; Russell M. Kulsrud

2002-01-28T23:59:59.000Z

392

Fast superconducting magnetic field switch  

DOE Patents (OSTI)

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.

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

1996-01-01T23:59:59.000Z

393

Magnetohydrodynamic evolution of magnetic skeletons  

E-Print Network (OSTI)

The heating of the solar corona is likely to be due to reconnection of the highly complex magnetic field that threads throughout its volume. We have run a numerical experiment of an elementary interaction between the magnetic field of two photospheric sources in an overlying field that represents a fundamental building block of the coronal heating process. The key to explaining where, how and how much energy is released during such an interaction is to calculate the resulting evolution of the magnetic skeleton. A skeleton is essentially the web of magnetic flux surfaces (called separatrix surfaces) that separate the coronal volume into topologically distinct parts. For the first time the skeleton of the magnetic field in a 3D numerical MHD experiment is calculated and carefully analysed, as are the ways in which it bifurcates into different topologies. A change in topology normally changes the number of magnetic reconnection sites. In our experiment, the magnetic field evolves through a total of six distinct ...

Haynes, A L; Galsgaard, K; Priest, E R; Haynes, Andrew L.; Parnell, Clare E.; Galsgaard, Klaus; Priest, Eric R.

2007-01-01T23:59:59.000Z

394

Giant magnetoresistance in nanogranular magnets.  

Science Conference Proceedings (OSTI)

We study the giant magnetoresistance of nanogranular magnets in the presence of an external magnetic field and finite temperature. We show that the magnetization of arrays of nanogranular magnets has hysteretic behavior at low temperatures leading to a double peak in the magnetoresistance which coalesces at high temperatures into a single peak. We numerically calculate the magnetization of magnetic domains and the motion of domain walls in this system using a combined mean-field approach and a model for an elastic membrane moving in a random medium, respectively. From the obtained results, we calculate the electric resistivity as a function of magnetic field and temperature. Our findings show excellent agreement with various experimental data.

Glatz, A.; Beloborodov, I. S.; Vinokur, V. M.; Materials Science Division; Univ. of Chicago

2008-05-01T23:59:59.000Z

395

Magnetic resonance apparatus  

DOE Patents (OSTI)

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.

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

1980-10-10T23:59:59.000Z

396

Magnetic liquefier for hydrogen  

DOE Green Energy (OSTI)

This document summarizes work done at the Astronautics Technology Center of the Astronautics Corporation of America (ACA) in Phase 1 of a four phase program leading to the development of a magnetic liquefier for hydrogen. The project involves the design, fabrication, installation, and operation of a hydrogen liquefier providing significantly reduced capital and operating costs, compared to present liquefiers. To achieve this goal, magnetic refrigeration, a recently developed, highly efficient refrigeration technology, will be used for the liquefaction process. Phase 1 project tasks included liquefier conceptual design and analysis, preliminary design of promising configurations, design selection, and detailed design of the selected design. Fabrication drawings and vendor specifications for the selected design were completed during detailed design. The design of a subscale, demonstration magnetic hydrogen liquefier represents a significant advance in liquefaction technology. The cost reductions that can be realized in hydrogen liquefaction in both the subscale and, more importantly, in the full-scale device are expected to have considerable impact on the use of liquid hydrogen in transportation, chemical, and electronic industries. The benefits to the nation from this technological advance will continue to have importance well into the 21st century.

NONE

1992-12-31T23:59:59.000Z

397

ARM - Measurement - Hydrometeor image  

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

image image ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Hydrometeor image Images of hydrometeors from which one can derive characteristics such as size and shape. Categories Cloud Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. Field Campaign Instruments LEARJET : Lear Jet PARTIMG : Particle imager UAV-PROTEUS-MICRO : Proteus Cloud Microphysics Instruments SPEC-CPI : Stratton Park Engineering Company - Cloud particle imager UAV-PROTEUS : UAV Proteus

398

Video image position determination  

DOE Patents (OSTI)

The present invention generally relates to the control of video and optical information and, more specifically, to control systems utilizing video images to provide control. Accurate control of video images and laser beams is becoming increasingly important as the use of lasers for machine, medical and experimental processes escalates. In, AURORA, an installation at Los Alamos National Laboratory dedicated to laser fusion research, it is necessary to precisely control the path and angle of up to 96 lasers beams. This invention is comprised of an optical beam position controller in which a video camera captures an image of the beam in its video frames, and conveys those images to a processing board which calculates the centroid coordinates for the image. The image coordinates are used by motor controllers and stepper motors to position the beam in a predetermined alignment. In one embodiment, system noise, used in conjunction with Bernoulli trials, yields higher resolution centroid coordinates.

Christensen, W.; Anderson, F.L.; Kortegaard, B.L.

1990-01-01T23:59:59.000Z

399

Video image position determination  

DOE Patents (OSTI)

The present invention generally relates to the control of video and optical information and, more specifically, to control systems utilizing video images to provide control. Accurate control of video images and laser beams is becoming increasingly important as the use of lasers for machine, medical and experimental processes escalates. In, AURORA, an installation at Los Alamos National Laboratory dedicated to laser fusion research, it is necessary to precisely control the path and angle of up to 96 lasers beams. This invention is comprised of an optical beam position controller in which a video camera captures an image of the beam in its video frames, and conveys those images to a processing board which calculates the centroid coordinates for the image. The image coordinates are used by motor controllers and stepper motors to position the beam in a predetermined alignment. In one embodiment, system noise, used in conjunction with Bernoulli trials, yields higher resolution centroid coordinates.

Christensen, W.; Anderson, F.L.; Kortegaard, B.L.

1990-12-31T23:59:59.000Z

400

Linear Collider Final Focus Magnet Construction | Superconducting Magnet  

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

Linear Collider Final Focus Magnet Construction Linear Collider Final Focus Magnet Construction The final focus magnets for the International Linear Collider require very small quadrupoles be placed within the detector background field for both the entrance and exit beams. The use of superconducting magnets for this function provide solutions to several problems confronting the machine designers. One constraint is the operation within the 3 tesla detector field. The direct wind magnets are capable of operation without the use of magnetic materials in their construction, making them ideal for compact focussing solutions within detectors. The second constraint is the small physical size dictated by the crossing angle of the beams and proximity to the IR within the detector solenoid. The Direct Wind design does not require a collar to withstand Lorentz

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


401

Ferroelectric optical image comparator  

DOE Patents (OSTI)

A ferroelectric optical image comparator has a lead lanthanum zirconate titanate thin-film device which is constructed with a semi-transparent or transparent conductive first electrode on one side of the thin film, a conductive metal second electrode on the other side of the thin film, and the second electrode is in contact with a nonconducting substrate. A photoinduced current in the device represents the dot product between a stored image and an image projected onto the first electrode. One-dimensional autocorrelations are performed by measuring this current while displacing the projected image. 7 figures.

Butler, M.A.; Land, C.E.; Martin, S.J.; Pfeifer, K.B.

1993-11-30T23:59:59.000Z

402

Ferroelectric optical image comparator  

DOE Patents (OSTI)

A ferroelectric optical image comparator has a lead lanthanum zirconate titanate thin-film device which is constructed with a semi-transparent or transparent conductive first electrode on one side of the thin film, a conductive metal second electrode on the other side of the thin film, and the second electrode is in contact with a nonconducting substrate. A photoinduced current in the device represents the dot product between a stored image and an image projected onto the first electrode. One-dimensional autocorrelations are performed by measuring this current while displacing the projected image.

Butler, Michael A. (Albuquerque, NM); Land, Cecil E. (Albuquerque, NM); Martin, Stephen J. (Albuquerque, NM); Pfeifer, Kent B. (Los Lunas, NM)

1993-01-01T23:59:59.000Z

403

Image Shift Measurement  

Science Conference Proceedings (OSTI)

... Set the write directory to a new folder for the cropped images. Use Process Folder / Text file / Template to make the boiler plate processing file. ...

404

Imaging Beyond Optics  

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

Views" piece in that same issue. "Generations of astronomers have used interferometric tests to achieve the proper shape of their mirrors before using them to image the heavens....

405

Quantitative luminescence imaging system  

DOE Patents (OSTI)

The QLIS images and quantifies low-level chemiluminescent reactions in an electromagnetic field. It is capable of real time nonperturbing measurement and simultaneous recording of many biochemical and chemical reactions such as luminescent immunoassays or enzyme assays. The system comprises image transfer optics, a low-light level digitizing camera with image intensifying microchannel plates, an image process or, and a control computer. The image transfer optics may be a fiber image guide with a bend, or a microscope, to take the light outside of the RF field. Output of the camera is transformed into a localized rate of cumulative digitalized data or enhanced video display or hard-copy images. The system may be used as a luminescent microdosimetry device for radiofrequency or microwave radiation, as a thermal dosimeter, or in the dosimetry of ultra-sound (sonoluminescence) or ionizing radiation. It provides a near-real-time system capable of measuring the extremely low light levels from luminescent reactions in electromagnetic fields in the areas of chemiluminescence assays and thermal microdosimetry, and is capable of near-real-time imaging of the sample to allow spatial distribution analysis of the reaction. It can be used to instrument three distinctly different irradiation configurations, comprising (1) RF waveguide irradiation of a small Petri-dish-shaped sample cell, (2) RF irradiation of samples in a microscope for the microscopie imaging and measurement, and (3) RF irradiation of small to human body-sized samples in an anechoic chamber.

Erwin, David N. (San Antonio, TX); Kiel, Johnathan L. (San Antonio, TX); Batishko, Charles R. (West Richland, WA); Stahl, Kurt A. (Richland, WA)

1990-01-01T23:59:59.000Z

406

Quantitative luminescence imaging system  

DOE Patents (OSTI)

The QLIS images and quantifies low-level chemiluminescent reactions in an electromagnetic field. It is capable of real time nonperturbing measurement and simultaneous recording of many biochemical and chemical reactions such as luminescent immunoassays or enzyme assays. The system comprises image transfer optics, a low-light level digitizing camera with image intensifying microchannel plates, an image process or, and a control computer. The image transfer optics may be a fiber image guide with a bend, or a microscope, to take the light outside of the RF field. Output of the camera is transformed into a localized rate of cumulative digitalized data or enhanced video display or hard-copy images. The system may be used as a luminescent microdosimetry device for radiofrequency or microwave radiation, as a thermal dosimeter, or in the dosimetry of ultra-sound (sonoluminescence) or ionizing radiation. It provides a near-real-time system capable of measuring the extremely low light levels from luminescent reactions in electromagnetic fields in the areas of chemiluminescence assays and thermal microdosimetry, and is capable of near-real-time imaging of the sample to allow spatial distribution analysis of the reaction. It can be used to instrument three distinctly different irradiation configurations, comprising (1) RF waveguide irradiation of a small Petri-dish-shaped sample cell, (2) RF irradiation of samples in a microscope for the microscopic imaging and measurement, and (3) RF irradiation of small to human body-sized samples in an anechoic chamber. 22 figs.

Erwin, D.N.; Kiel, J.L.; Batishko, C.R.; Stahl, K.A.

1990-08-14T23:59:59.000Z

407

Kursk Site Image #1  

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

Graphs Image KRS-1: Clipping above-ground biomass at the Kursk grassland site, Russia. (Dr. Kira Khodashova and student Nina N., Moscow State University, are estimating monthly...

408

Manhattan Project: Places Images  

Office of Scientific and Technical Information (OSTI)

PLACES IMAGES PLACES IMAGES Resources > Photo Gallery Scroll down to see each of these images individually. The images are: 1. Remains of a Shinto Shrine, Nagasaki, October 1945 (courtesy the United States Marine Corps, Lieutenant R. J. Battersby, photographer, via the National Archives); 2. University of California, Berkeley, 1940 (courtesy the Lawrence Berkeley National Laboratory); 3. Aerial photograph of the Trinity Site after the test (courtesy the Federation of American Scientists); 4. Aerial photograph of Hiroshima before the bombing; 5. Columbia University, 1903 (courtesy the Library of Congress; this photograph originated from the Detroit Publishing Company; it was a 1949 gift to the Library of Congress from the State Historical Society of Colorado).

409

Processing of Soft Magnetic Alloys in High Magnetic Field  

Science Conference Proceedings (OSTI)

... Magnetic Materials for Use in Energy-efficient Distribution Transformers ... Novel Morphology of Highly Efficient Two-phase Ferrite Cores for Power Systems

410

Role of Magnetic Fields and Texturing to Improved Magnetic Materials  

Science Conference Proceedings (OSTI)

Mar 13, 2012 ... Experiments to observe the structural and magnetic phase transformations were performed at the Spallation Neutron Source (SNS) at Oak...

411

MAGNETIC PROPERTIES OF THE ALS BOOSTER SYNCHROTRON ENGINEERING MODEL MAGNETS  

E-Print Network (OSTI)

Dynamic Aperture of the ALS Booster Synchrotron." presented25953 MAGNETIC PROPERTIES OF TIIE ALS BOOSTER SYNCIIROlRONMagnetic Measurements of the ALS Booster Dipole Engineering

Keller, R.

2010-01-01T23:59:59.000Z

412

Field polarity dependent nucleation of superconductivity in quasi-one-dimensional magnetic templates.  

SciTech Connect

We investigate the nucleation of superconductivity in an Al/Al{sub 2}O{sub 3}/Py trilayer system by electrical transport measurements. Magnetic force microscopy images taken at room temperature show that the 0.7 {micro}m thick Py-film form stripes of magnetic domains with alternating out-of-plane stray field. After applying a strong out of plane magnetic field H the superconductor/normal phase boundary becomes asymmetric with respect to H = 0. This lack of field polarity symmetry results from the unbalanced size distribution of domains with opposite polarity.

Ataklti, G. W.; Silhanek, A. V.; Van de Vondel, J.; Gillijns, W.; Belkin, A.; Karapetrov, G.; Moshchalkov, V. V.; Materials Science Division; Katholieke Univ. Leuven; Illinois Inst. of Tech.

2010-01-01T23:59:59.000Z

413

Brett Parker | Superconducting Magnet Division  

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

Brett Parker Brett Parker Recent Presentations "BNL Direct Wind Magnets," (pdf) presentation dedicated to the memory of Pat Thompson given at the 22nd Magnet Technology Conference (MT22), September 11 - 16, 2011, Marseille, France A Review of BNL Direct-Wind Superconducting IR Magnet Experience, (pdf) presented at the 30th Advanced ICFA Beam Dynamics Workshop on High Luminosity e+e- Collisions, October 13 - 16, 2003, Stanford, California The Serpentine Coil Design for BEPC-II Superconducting IR Magnets, (pdf) presented at the "Mini-Workshop on BEPC-II IR Design", January 12 - 16, 2004, Beijing, P.R. China Ma nufacture of a Superconducting Octupole Magnet for the ALPHA Experiment at CERN using the Direct Wind Machine Presentations Prior to 2004 Superconducting Final Focus Magnet Issues (pdf), presented at

414

Thin film superconductor magnetic bearings  

DOE Patents (OSTI)

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.

Weinberger, Bernard R. (Avon, CT)

1995-12-26T23:59:59.000Z

415

Spinning a New Type of Magnetic Field | U.S. DOE Office of Science (SC)  

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

Spinning a New Type of Magnetic Field Spinning a New Type of Magnetic Field Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic Energy Sciences Advisory Committee (BESAC) News & Resources Contact Information Basic Energy Sciences U.S. Department of Energy SC-22/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3081 F: (301) 903-6594 E: sc.bes@science.doe.gov More Information » October 2013 Spinning a New Type of Magnetic Field Harnessing the spins of electrons in a new way - enabling efficient magnetic switching and holding promise for spintronic devices. Print Text Size: A A A Subscribe FeedbackShare Page Click to enlarge photo. Enlarge Photo Image courtesy of John Xiao Schematic of mechanism for generating a magnetic field. The system consists

416

Static magnetic fields: A summary of biological interactions, potential health effects, and exposure guidelines  

SciTech Connect

Interest in the mechanisms of interaction and the biological effects of static magnetic fields has increased significantly during the past two decades as a result of the growing number of applications of these fields in research, industry and medicine. A major stimulus for research on the bioeffects of static magnetic fields has been the effort to develop new technologies for energy production and storage that utilize intense magnetic fields (e.g., thermonuclear fusion reactors and superconducting magnet energy storage devices). Interest in the possible biological interactions and health effects of static magnetic fields has also been increased as a result of recent developments in magnetic levitation as a mode of public transportation. In addition, the rapid emergence of magnetic resonance imaging as a new clinical diagnostic procedure has, in recent years, provided a strong rationale for defining the possible biological effects of magnetic fields with high flux densities. In this review, the principal interaction mechanisms of static magnetic fields will be described, and a summary will be given of the present state of knowledge of the biological, environmental, and human health effects of these fields.

Tenforde, T.S.

1992-05-01T23:59:59.000Z

417

Magnetism in low dimensionality.  

SciTech Connect

The collective creativity of those working in the field of surface magnetism has stimulated an impressive range of advances. Once wary, theorists are now eager to enter the field. The present article attempts to take a snapshot of where the field has been, with an eye to the more speculative issue of where it is going. Selective examples are used to highlight three general areas of interest (1) characterization techniques, (2) materials properties, and (3) theoretical/simulational advances. Emerging directions are identified and discussed, including laterally confined nanomagnetism and spintronics.

Bader, S. D.; Materials Science Division

2002-03-10T23:59:59.000Z

418

Automatic Image Orientation Determination with Natural Image Statistics  

E-Print Network (OSTI)

Automatic Image Orientation Determination with Natural Image Statistics Siwei Lyu Dept. of Computer a new method for automatically determining image orientations. This method is based on a set of natural image statistics collected from a multi- scale multi-orientation image decomposition (e.g., wavelets

Lyu, Siwei

419

Quantum Imaging: Enhanced Image Formation Using Quantum States of Light  

E-Print Network (OSTI)

Quantum Imaging: Enhanced Image Formation Using Quantum States of Light Robert W. Boyd, Kam Wai, University of Rochester, Rochester, NY 14627, USA ABSTRACT We review recent research in the field of quantum imaging. Quantum imaging deals with the formation of images that possess higher resolution or better

Boyd, Robert W.

420

Searching for a link between the presence of chemical spots on the surface of HgMn stars and their weak magnetic fields  

E-Print Network (OSTI)

We present the results of mapping the HgMn star AR Aur using the Doppler Imaging technique for several elements and discuss the obtained distributions in the framework of a magnetic field topology.

Savanov, I S; Gonzlez, J F; Schller, M

2009-01-01T23:59:59.000Z

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


421

Magnetic Materials for Green Innovation  

Science Conference Proceedings (OSTI)

... Magnetic Materials for Use in Energy-efficient Distribution Transformers ... Novel Morphology of Highly Efficient Two-phase Ferrite Cores for Power Systems

422

Reversal mechanisms in perpendicularly magnetized ...  

Science Conference Proceedings (OSTI)

... I. INTRODUCTION Magnetic nanostructures have potential applications in emerging technologies including spintronics,1,2 bit patterned media,36 ...

2008-07-16T23:59:59.000Z

423

Measurements of magnetic field alignment  

Science Conference Proceedings (OSTI)

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.

Kuchnir, M.; Schmidt, E.E.

1987-11-06T23:59:59.000Z

424

Magnetic Refrigeration - Programmaster.org  

Science Conference Proceedings (OSTI)

Aug 6, 2013 ... Magnetic Refrigeration a 21st Century Highly Efficient and Green Cooling .... In order to advance their incorporation in prototypes and industrial...

425

Textured Polycrystalline Permanent Magnet Nanoflakes  

Science Conference Proceedings (OSTI)

... high electrical resistivity, which will reduce eddy current losses and improve motor efficiency. ... Combinatorial Search of Rare-Earth-Free Permanent Magnets

426

RECENT ADVANCES IN THE TECHNOLOGY OF SUPERCONDUCTING ACCELERATOR MAGNETS  

E-Print Network (OSTI)

Accelerator Magnets, Brookhaven National Laboratory,in Superconducting Magnets,- Brookhaven National Laboratory,Accelerator Magnet Wire," Brookhaven National Laboratory,

Taylor, C.E.

2010-01-01T23:59:59.000Z

427

Fabrication of Nanocrystalline Magnetic Materials for use in Energy ...  

Science Conference Proceedings (OSTI)

Symposium, Magnetic Materials for Energy Applications IV ... magnetic softness, resulting in limited saturation magnetization, Bs. Chemical optimization, thus,...

428

Medical imaging systems  

DOE Patents (OSTI)

A medical imaging system provides simultaneous rendering of visible light and fluorescent images. The system may employ dyes in a small-molecule form that remains in a subject's blood stream for several minutes, allowing real-time imaging of the subject's circulatory system superimposed upon a conventional, visible light image of the subject. The system may also employ dyes or other fluorescent substances associated with antibodies, antibody fragments, or ligands that accumulate within a region of diagnostic significance. In one embodiment, the system provides an excitation light source to excite the fluorescent substance and a visible light source for general illumination within the same optical guide that is used to capture images. In another embodiment, the system is configured for use in open surgical procedures by providing an operating area that is closed to ambient light. More broadly, the systems described herein may be used in imaging applications where a visible light image may be usefully supplemented by an image formed from fluorescent emissions from a fluorescent substance that marks areas of functional interest.

Frangioni, John V. (Wayland, MA)

2012-07-24T23:59:59.000Z

429

DOUBLE MAJORS Imaging Science + ...  

E-Print Network (OSTI)

DOUBLE MAJORS Imaging Science + ... Applied Mathematics Biomedical Sciences Computer Science Undergraduate Research Internships and Cooperative Education (Co-op) (optional) Study Abroad WHY IMAGING SCIENCE Science: BS, MS, PhD Color Science: MS, PhD BS + MS/PhD Combos HUMAN VISION BIO- MEDICAL ASTRO- PHYSICS

Zanibbi, Richard

430

Heart imaging method  

DOE Patents (OSTI)

A method for providing an image of the human heart's electrical system derives time-of-flight data from an array of EKG electrodes and this data is transformed into phase information. The phase information, treated as a hologram, is reconstructed to provide an image in one or two dimensions of the electrical system of the functioning heart.

Collins, H. Dale (Richland, WA); Gribble, R. Parks (Richland, WA); Busse, Lawrence J. (Littleton, CO)

1991-01-01T23:59:59.000Z

431

Full Size Image - Energy Innovation Portal  

This schematic of the magneto-optic detection system illustrates a magnetic nanoparticle stimulated by external time-varying magnetic fields. The dynamic magnetic ...

432

J-PARC Correctors | Superconducting Magnet Division  

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

Magnet Construction Magnet Construction The final turn of the J-PARC extracted proton beam is a superconducting combined function magnet line. The combined function magnets are dipole cable magnets, typical of cold mass collared magnets, but have been designed to include a large component of quadrupole field. This provides both bending and focussing of the proton beam prior to target impact, where neutrinos will be produced. The BNL Superconducting Magnet Division is using its direct wind facility to produce superconducting corrector magnets to be used in conjunction with the combined function magnets. combined function magnet The first direct wind magnet set designed and fabricated is a combined function magnet with an additional skew dipole. This magnet is intended to be used within the cable collared combined function dipole used for the

433

Manhattan Project: Image Retouching`  

Office of Scientific and Technical Information (OSTI)

Image Retouching Image Retouching Resources > Photo Gallery Smyth Report (original) Smyth Report (retouched) Images on this web site have sometimes been "retouched." In every case, however, the intention has been only to restore the image as much as possible to its original condition. Above is a rather extreme example-"before and after" versions of the cover of the Smyth Report (Henry DeWolf Smyth, Atomic Energy for Military Purposes: The Official Report on the Development of the Atomic Bomb under the Auspices of the United States Government, 1940-1945 (Princeton, NJ: Princeton University Press, 1945)). The Smyth Report was commissioned by Leslie Groves and originally issued by the Manhattan Engineer District. Princeton University Press reprinted it in book form as a "public service" with "reproduction in whole or in part authorized and permitted.") Larger versions of the same images are below.

434

GTL Image Gallery  

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

Human Genome Project Information • Genomic Science • Microbial Genome Program • sitemap • home Human Genome Project Information • Genomic Science • Microbial Genome Program • sitemap • home Announcing the New Image Gallery Visit the new Image Gallery for an expanded suite of images Biofuels Browse the 2010 "Bioenergy Research Centers: An Overview of the Science" Brochure Gallery. Browse the 2006 "Breaking the Biological Barriers to Cellulosic Ethanol: A Joint Research Agenda" Report Gallery. Browse more biofuels images (includes the June 2006 "Understanding Biomass" Primer Gallery). Systems Biology Browse the August 2005 "Genomics:GTL Roadmap: Systems Biology for Energy and Environment" Gallery. Basic Genomics Browse the Human Chromosome Gallery. Browse more Basic Genomics images. Carbon Cycling

435

Efficient Graffiti Image Retrieval  

Science Conference Proceedings (OSTI)

Research of graffiti character recognition and retrieval, as a branch of traditional optical character recognition (OCR), has started to gain attention in recent years. We have investigated the special challenge of the graffiti image retrieval problem and propose a series of novel techniques to overcome the challenges. The proposed bounding box framework locates the character components in the graffiti images to construct meaningful character strings and conduct image-wise and semantic-wise retrieval on the strings rather than the entire image. Using real world data provided by the law enforcement community to the Pacific Northwest National Laboratory, we show that the proposed framework outperforms the traditional image retrieval framework with better retrieval results and improved computational efficiency.

Yang, Chunlei; Wong, Pak C.; Ribarsky, William; Fan, Jianping

2012-07-05T23:59:59.000Z

436

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

DOE Patents (OSTI)

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.

Jiles, D.C.

1991-04-16T23:59:59.000Z

437

Correction magnets for the Fermilab Recycler Ring  

SciTech Connect

In the commissioning of the Fermilab Recycler ring the need for higher order corrector magnets in the regions near beam transfers was discovered. Three types of permanent magnet skew quadrupoles, and two types of permanent magnet sextupoles were designed and built. This paper describes the need for these magnets, the design, assembly, and magnetic measurements.

James T Volk et al.

2003-05-27T23:59:59.000Z

438

Adaptive wiener image restoration kernel  

DOE Patents (OSTI)

A method and device for restoration of electro-optical image data using an adaptive Wiener filter begins with constructing imaging system Optical Transfer Function, and the Fourier Transformations of the noise and the image. A spatial representation of the imaged object is restored by spatial convolution of the image using a Wiener restoration kernel.

Yuan, Ding (Henderson, NV)

2007-06-05T23:59:59.000Z

439

Edge structure preserving image denoising  

Science Conference Proceedings (OSTI)

Image denoising is important in image analysis. It is often used for pre-processing images so that subsequent image analysis is more reliable. Besides noise removal, one important requirement for image denoising procedures is that they should preserve ... Keywords: Angles, Curvature, Edges, Jump-preserving surface estimation, Local smoothing, Nonparametric regression, Surface estimation

Peihua Qiu; Partha Sarathi Mukherjee

2010-10-01T23:59:59.000Z

440

IMAGING: the Neutron Imaging Prototype Facility at HFIR | ORNL...  

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

Neutron Imaging Prototype Facility CG-1D flight tubes Neutron imaging beam line CG-1D. The CG-1D beam is used for neutron imaging measurements and can be configured for white beam...

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


441

Complex Magnetic Evolution and Magnetic Helicity in the Solar Atmosphere  

E-Print Network (OSTI)

Solar atmosphere is a single system unified by the presence of large-scale magnetic fields. Topological changes in magnetic fields that occur in one place may have consequences for coronal heating and eruptions for other, even remote locations. Coronal magnetic fields also play role in transport of magnetic helicity from Sun's subphotosphere/upper convection zone to the interplanetary space. We discuss observational evidence pertinent to some aspects of the solar corona being a global interconnected system, i.e., large-scale coronal heating due to new flux emergence, eruption of chromospheric filament resulting from changes in magnetic topology triggered by new flux emergence, sunspots rotation as manifestation of transport of helicity through the photosphere, and potential consequences of re-distribution of energy from solar luminosity to the dynamo for solar cycle variations of solar irradiance.

Pevtsov, Alexei A

2013-01-01T23:59:59.000Z

442

Magnetic response to applied electrostatic field in external magnetic field  

E-Print Network (OSTI)

We show, within QED and other possible nonlinear theories, that a static charge localized in a finite domain of space becomes a magnetic dipole, if it is placed in an external (constant and homogeneous) magnetic field in the vacuum. The magnetic moment is quadratic in the charge, depends on its size and is parallel to the external field, provided the charge distribution is at least cylindrically symmetric. This magneto-electric effect is a nonlinear response of the magnetized vacuum to an applied electrostatic field. Referring to a simple example of a spherically-symmetric applied field, the nonlinearly induced current and its magnetic field are found explicitly throughout the space, the pattern of lines of force is depicted, both inside and outside the charge, which resembles that of a standard solenoid of classical magnetostatics.

T. C. Adorno; D. M. Gitman; A. E. Shabad

2013-11-16T23:59:59.000Z

443

Magnetohydrodynamic evolution of magnetic skeletons  

E-Print Network (OSTI)

The heating of the solar corona is likely to be due to reconnection of the highly complex magnetic field that threads throughout its volume. We have run a numerical experiment of an elementary interaction between the magnetic field of two photospheric sources in an overlying field that represents a fundamental building block of the coronal heating process. The key to explaining where, how and how much energy is released during such an interaction is to calculate the resulting evolution of the magnetic skeleton. A skeleton is essentially the web of magnetic flux surfaces (called separatrix surfaces) that separate the coronal volume into topologically distinct parts. For the first time the skeleton of the magnetic field in a 3D numerical MHD experiment is calculated and carefully analysed, as are the ways in which it bifurcates into different topologies. A change in topology normally changes the number of magnetic reconnection sites. In our experiment, the magnetic field evolves through a total of six distinct topologies. Initially, no magnetic flux joins the two sources. Then a new type of bifurcation, called a global double-separator bifurcation, takes place: this bifurcation is likely to be one of the main ways in which new separators are created in the corona (separators are field lines at which 3D reconnection takes place). This is the first of five bifurcations in which the skeleton becomes progressively more complex before simplifying. Surprisingly, for such a simple initial state, at the peak of complexity there are five separators and eight flux domains present.

Andrew L. Haynes; Clare E. Parnell; Klaus Galsgaard; Eric R. Priest

2007-02-22T23:59:59.000Z

444

LABORATORY VI ELECTRICITY FROM MAGNETISM  

E-Print Network (OSTI)

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

Minnesota, University of

445

Magnetic Resonance Facility (Fact Sheet)  

DOE Green Energy (OSTI)

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.

Not Available

2012-03-01T23:59:59.000Z

446

Magnetic-field-dosimetry system  

DOE Patents (OSTI)

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.

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

1981-01-21T23:59:59.000Z

447

Image Windows - description of data types  

Science Conference Proceedings (OSTI)

... image, or RGB color image. cstack Stack of color (RGB) images. FRED (text) window; Dialog; (various) graphics windows.

448

Ramesh Gupta | Superconducting Magnet Division  

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

Ramesh Gupta Ramesh Gupta Ramesh Gupta has always been a leader in the world of superconducting magnets, which are essential to great modern accelerators such as the Relativistic Heavy Ion Collider at BNL, and the Large Hadron Collider at CERN, Switzerland. For the past decade, Lab researchers have been exploring the use of new materials that become superconducting at higher temperatures. Gupta, head of the High Temperature Superconductor (HTS) Research and Development Group in the Superconducting Magnet Division, is among those exploring avenues for HTS magnets that are energy efficient and have magnetic fields that are a million times stronger than the Earth's. These new magnets could revolutionize use in future accelerators, play a key role in energy efficiency and storage, and make possible new

449

Accuracy of magnetic energy computations  

E-Print Network (OSTI)

For magnetically driven events, the magnetic energy of the system is the prime energy reservoir that fuels the dynamical evolution. In the solar context, the free energy is one of the main indicators used in space weather forecasts to predict the eruptivity of active regions. A trustworthy estimation of the magnetic energy is therefore needed in three-dimensional models of the solar atmosphere, eg in coronal fields reconstructions or numerical simulations. The expression of the energy of a system as the sum of its potential energy and its free energy (Thomson's theorem) is strictly valid when the magnetic field is exactly solenoidal. For numerical realizations on a discrete grid, this property may be only approximately fulfilled. We show that the imperfect solenoidality induces terms in the energy that can lead to misinterpreting the amount of free energy present in a magnetic configuration. We consider a decomposition of the energy in solenoidal and nonsolenoidal parts which allows the unambiguous estimation...

Valori, G; Pariat, E; Masson, S

2013-01-01T23:59:59.000Z

450

Scanning computed confocal imager  

DOE Patents (OSTI)

There is provided a confocal imager comprising a light source emitting a light, with a light modulator in optical communication with the light source for varying the spatial and temporal pattern of the light. A beam splitter receives the scanned light and direct the scanned light onto a target and pass light reflected from the target to a video capturing device for receiving the reflected light and transferring a digital image of the reflected light to a computer for creating a virtual aperture and outputting the digital image. In a transmissive mode of operation the invention omits the beam splitter means and captures light passed through the target.

George, John S. (Los Alamos, NM)

2000-03-14T23:59:59.000Z

451

Purification of recombinant proteins with magnetic nanoclusters  

E-Print Network (OSTI)

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

Ditsch, Andre (Andre Paul)

2005-01-01T23:59:59.000Z

452

LHC Dipole Acceptance | Superconducting Magnet Division  

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

Magnet Division designed, constructed and tested dipole magnets for the Large Hadron Collider (LHC) at CERN. Each of the BNL-built dipole magnets was tested at the Lab's...

453

Magnetic nanostructures patterned by block copolymer lithography  

E-Print Network (OSTI)

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

Ilievski, Filip, 1980-

2008-01-01T23:59:59.000Z

454

A direct search for Dirac magnetic monopoles  

E-Print Network (OSTI)

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

Mulhearn, Michael James

2005-01-01T23:59:59.000Z

455

Imaging of Acoustic Waves in Sand  

SciTech Connect

There is considerable interest in detecting objects such as landmines shallowly buried in loose earth or sand. Various techniques involving microwave, acoustic, thermal and magnetic sensors have been used to detect such objects. Acoustic and microwave sensors have shown promise, especially if used together. In most cases, the sensor package is scanned over an area to eventually build up an image or map of anomalies. We are proposing an alternate, acoustic method that directly provides an image of acoustic waves in sand or soil, and their interaction with buried objects. The INEEL Laser Ultrasonic Camera utilizes dynamic holography within photorefractive recording materials. This permits one to image and demodulate acoustic waves on surfaces in real time, without scanning. A video image is produced where intensity is directly and linearly proportional to surface motion. Both specular and diffusely reflecting surfaces can be accomodated and surface motion as small as 0.1 nm can be quantitatively detected. This system was used to directly image acoustic surface waves in sand as well as in solid objects. Waves as frequencies of 16 kHz were generated using modified acoustic speakers. These waves were directed through sand toward partially buried objects. The sand container was not on a vibration isolation table, but sat on the lab floor. Interaction of wavefronts with buried objects showed reflection, diffraction and interference effects that could provide clues to location and characteristics of buried objects. Although results are preliminary, success in this effort suggests that this method could be applied to detection of buried landmines or other near-surface items such as pipes and tanks.

Deason, Vance Albert; Telschow, Kenneth Louis; Watson, Scott Marshall

2003-08-01T23:59:59.000Z

456

Superconducting magnetic energy storage  

DOE Green Energy (OSTI)

Fusion power production requires energy storage and transfer on short time scales to create confining magnetic fields and for heating plasmas. The theta-pinch Scyllac Fusion Test Reactor (SFTR) requires 480 MJ of energy to drive the 5-T compression field with a 0.7-ms rise time. Tokamak Experimental Power Reactors (EPR) require 1 to 2 GJ of energy with a 1 to 2-s rise time for plasma ohmic heating. The design, development, and testing of four 300-kJ energy storage coils to satisfy the SFTR needs are described. Potential rotating machinery and homopolar energy systems for both the Reference Theta-Pinch Reactor (RTPR) and tokamak ohmic-heating are presented.

Rogers, J.D.

1976-01-01T23:59:59.000Z

457

Superconducting magnetic energy storage  

SciTech Connect

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.

Hassenzahl, W.

1988-08-01T23:59:59.000Z

458

Origin of solar magnetism  

E-Print Network (OSTI)

The most promising model for explaining the origin of solar magnetism is the flux transport dynamo model, in which the toroidal field is produced by differential rotation in the tachocline, the poloidal field is produced by the Babcock--Leighton mechanism at the solar surface and the meridional circulation plays a crucial role. After discussing how this model explains the regular periodic features of the solar cycle, we come to the questions of what causes irregularities of solar cycles and whether we can predict future cycles. Only if the diffusivity within the convection zone is sufficiently high, the polar field at the sunspot minimum is correlated with strength of the next cycle. This is in conformity with the limited available observational data.

Choudhuri, Arnab Rai

2010-01-01T23:59:59.000Z

459

Ghost Imaging with Blackbody Radiation  

E-Print Network (OSTI)

We present a theoretical study of ghost imaging by using blackbody radiation source. A Gaussian thin lens equation for the ghost imaging, which depends on both paths, is derived. The dependences of the visibility and quality of the image on the transverse size and temperature of the blackbody are studied. The main differences between the ghost imaging by using the blackbody radiation and by using the entangled photon pairs are image-forming equation, and the visibility and quality of the image

Yangjian Cai; Shiyao Zhu

2004-07-29T23:59:59.000Z

460

Electronic Structure and Magnetism in Diluted Magnetic Semiconductors  

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

Electronic Structure and 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 magnetic semiconductors created by doping ions like Mn, Fe, or Co having a net spin into a semiconducting host such as GaAs, ZnO, or GaN. The interaction among these spins leads to ferromagnetic order at low temperatures, which is necessary to create spin-polarized carriers. A research team working at ALS Beamline 4.0.2 and European Synchrotron Radiation Facility Beamline ID8 made a big leap forward in clarifying the microscopic picture of magnetism and anisotropy in Mn-doped GaAs by resolving localized and hybridized d states using angle-dependent x-ray magnetic circular dichroism (XMCD) measurements.

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461

Electronic Structure and Magnetism in Diluted Magnetic Semiconductors  

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

Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print 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 such as GaAs, ZnO, or GaN. The interaction among these spins leads to ferromagnetic order at low temperatures, which is necessary to create spin-polarized carriers. A research team working at ALS Beamline 4.0.2 and European Synchrotron Radiation Facility Beamline ID8 made a big leap forward in clarifying the microscopic picture of magnetism and anisotropy in Mn-doped GaAs by resolving localized and hybridized d states using angle-dependent x-ray magnetic circular dichroism (XMCD) measurements.

462

Electronic Structure and Magnetism in Diluted Magnetic Semiconductors  

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

Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print 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 such as GaAs, ZnO, or GaN. The interaction among these spins leads to ferromagnetic order at low temperatures, which is necessary to create spin-polarized carriers. A research team working at ALS Beamline 4.0.2 and European Synchrotron Radiation Facility Beamline ID8 made a big leap forward in clarifying the microscopic picture of magnetism and anisotropy in Mn-doped GaAs by resolving localized and hybridized d states using angle-dependent x-ray magnetic circular dichroism (XMCD) measurements.

463

Quantitative Imaging in Cell Biology  

E-Print Network (OSTI)

Quantitative! imaging! in! biology! is! concerned! with!Quantitative! imaging! in! biology! is! concerned! with!advances! in! cell! biology! by! enabling! the! tracking!

Yassif, Jaime

2012-01-01T23:59:59.000Z

464

NIST Hyperspectral Image Projector (HIP)  

Science Conference Proceedings (OSTI)

... In DLP systems, the projected image is made from a composite of grayscale images representing each of the RGB colors (red, green, and blue). ...

2013-08-02T23:59:59.000Z

465

NERSC Image and Video Galleries  

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

Archive User Science Images Home News & Publications Galleries Galleries 18.jpg NERSC Systems In this gallery view images and videos of the systems that undergird all NERSC...

466

MR Microscopy at the Cellular Level Gregory S. Boebinger, National High Magnetic Field Laboratory  

E-Print Network (OSTI)

). (1) Flint et al, Neuroimage 46:1037(2009) (2) Flint et al, Neuroimage. 52:556(2010) (3) Hansen et al, Neuroimage. 57:1458(2011) (4) Flint et al, Submitted (2011) #12;The era of extracting quantitative motor neuron from Magnetic Resonance Microscopic images (grayscale). ADC units are mm2s-1. (1) Flint et

Weston, Ken

467

Manhattan Project: People Images  

Office of Scientific and Technical Information (OSTI)

PEOPLE IMAGES PEOPLE IMAGES Resources > Photo Gallery Scroll down to see each of these images individually. The images are: 1. J. Robert Oppenheimer, Enrico Fermi, and Ernest Lawrence (courtesy the Lawrence Berkeley National Laboratory); 2. Hanford, Washington, workers sending money home (reproduced from the photo insert in F. G. Gosling, The Manhattan Project: Making the Atomic Bomb (Washington: History Division, Department of Energy, October 2001)); 3. Oppenheimer and Leslie Groves at the Trinity Site, September 1945 (reproduced from the cover of the Office of History and Heritage Resources publication: The Signature Facilities of the Manhattan Project (Washington: History Division, Department of Energy, 2001)); 4. A WAC detachment marching at Oak Ridge, Tennessee, June 1945 (courtesy the Army Corps of Engineers; it is reprinted in Rachel Fermi and Esther Samra, Picturing the Bomb: Photographs from the Secret World of the Manhattan Project (New York: Harry N. Abrams, Inc., Publishers, 1995), 40);

468

Manhattan Project: Science Images  

Office of Scientific and Technical Information (OSTI)

SCIENCE IMAGES SCIENCE IMAGES Resources > Photo Gallery Scroll down to see each of these images individually. The images are: 1. Fission (this graphic is adapted from a graphic originally produced by the Washington State Department of Health; the modifications are original to the History Division, now Office of History and Heritage Resources, 2003); 2. Fat Man (plutonium bomb), August 1945 (courtesy the U.S. Army Corps of Engineers (via theNational Archives)); 3. F Reactor Plutonium Production Complex Hanford, Washington, 1945; 4. A Cockroft-Walton machine at Los Alamos, New Mexico (courtesy the Los Alamos National Laboratory; it is reprinted in John F. Hogerton, ed., "Cockroft-Walton Machine," The Atomic Energy Deskbook (New York: Reinhold Publishing Corporation, 1963, prepared under the auspices of the Division of Technical Information, U.S. Atomic Energy Commission), 102);

469

Ferroelectric optical image comparator  

DOE Patents (OSTI)

The property of ferroelectric ceramics such as lead lanthanum zirconate titanate (PLZT) to store information has been known for many years. This relates to the property of ferroelectric ceramic materials to become permanently polarized when an electric signal is applied to the material. A ferroelectric optical image comparator has a lead lanthanum zirconate titanate thin-film device which is constructed with a semi-transparent or transparent conductive first electrode on one side of the thin film, a conductive metal second electrode on the other side of the thin film, and the second electrode is in contact with a nonconducting substrate. A photoinduced current in the device represents the dot product between a stored image and an image projected onto the first electrode. One-dimensional autocorrelations are performed by measuring this current while displacing the projected image. 5 figs.

Butler, M.A.; Land, C.E.; Martin, S.J.; Pfeifer, K.B.

1989-08-30T23:59:59.000Z

470

Resilient Image Fusion  

Science Conference Proceedings (OSTI)

The paper describes a distributed spectral-screening PCT algorithm for fusing hyper-spectral images in remote sensing applications. The algorithm provides intrusion tolerance from information warfare attacks using the notion of computational resiliency. ...

Tiranee Achalakul; Joohan Lee; Stephen Taylor

2000-08-01T23:59:59.000Z

471

Hierarchical image processing  

SciTech Connect

Most problems in image processing have structural aspects which are difficult to resolve using general methods. Use of heuristic methods is limited to cases where structural aspects are easy to resolve. An approach for hierarchical processing of images is described whereby structural aspects are resolved simultaneously with the analysis of data values. An effective use of a hierarchical structure puts strong restrictions upon information representation and operations. Information is represented in terms of compatibility of events, combined with a measure of confidence. Operations are of type symmetry operations, which allow data compression, context control and have a good descriptive power. The usefulness of these methods in image analysis and image processing is illustrated. 14 references.

Granlund, G.H.

1983-01-01T23:59:59.000Z

472

Imaging Fourier transform spectrometer  

DOE Patents (OSTI)

This invention is comprised of an imaging Fourier transform spectrometer having a Fourier transform infrared spectrometer providing a series of images to a focal plane array camera. The focal plane array camera is clocked to a multiple of zero crossing occurrences as caused by a moving mirror of the Fourier transform infrared spectrometer and as detected by a laser detector such that the frame capture rate of the focal plane array camera corresponds to a multiple of the zero crossing rate