Search Results - "Parks, Drew"

A significant advantage for trapped field magnet applications—A failure of the critical state model by Weinstein, Roy, Parks, Drew, Sawh, Ravi-Persad, Carpenter, Keith, Davey, Kent

“…Ongoing research has increased achievable field in trapped field magnets (TFMs) to multi-Tesla levels. This has greatly increased the attractiveness of TFMs…”
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Observation of a Bean Model Limit-A Large Decrease in Required Applied Activation Field for TFMs by Weinstein, Roy, Parks, Drew, Sawh, Ravi-Persad, Davey, Kent, Carpenter, Keith

“…Experiments are reported on pulsed activation of zero-field-cooled trapped field magnets (TFMs) containing improved broken-columnar pinning centers (PCs). The…”
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Improvement of high Tc superconductor by near-optimum pinning centers created by high Z, high-energy ions by Weinstein, Roy, Sawh, Ravi-Persad, Parks, Drew, Mayes, Billy

“…Damage tracks left by high Z, high-energy ions in high temperature superconductor (HTS) can serve the need to pin in place the magnetic field quanta. Such…”
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The Effect of a Ferromagnetic Medium on the Field of YBCO Trapped Field Magnets by Drew Parks, Weinstein, R., Davey, K., Sawh, R.-P., Mayes, B.W.

“…Trapped field magnets (TFMs) are characterized by the maximum field they can retain when they are activated in air (~vacuum). In some applications however,…”
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The Use of Very Thin TFMs in Electromechanical Devices by Davey, Kent, Weinstein, Roy, Sawh, Ravi-Persad, Parks, Drew

“…The contribution offered by this paper is to point out the advantage gained by the use of ultra thin trapped field magnets (TFMs) in electromechanical devices…”
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Rotating Cylinder Planetary Gear Motor by Davey, Kent, Hutson, Travis, McDonald, Larry, Ras, Chris, Weinstein, Roy, Parks, Drew, Sawh, Ravi Persad

“…This paper introduces a new electromechanical motor that incorporates free-spinning magnetized cylinders in the air gap. The motor has some of the features of…”
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Very high values of Jc obtained in NdBa2Cu3O by use of the U/n process by Weinstein, Roy, Sawh, Ravi-Persad, Parks, Drew, Murakami, Masato, Mochida, Tadashi, Chikumoto, Noriko, Krabbes, Gernot, Bieger, Wolfgang

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Simulating the Trapped [Formula Omitted] Field in Bulk Superconductors Using a Mutual Inductance Coupling Technique by Davey, Kent R, Weinstein, Roy, Parks, Drew, Sawh, Ravi

“…The field and current induced in a trapped field magnet during a transient current excitation is complicated by the fact that the conductivity of the material…”
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Improvement of high T c superconductor by near-optimum pinning centers created by high Z, high-energy ions by Weinstein, Roy, Sawh, Ravi-Persad, Parks, Drew, Mayes, Billy

“…Damage tracks left by high Z, high-energy ions in high temperature superconductor (HTS) can serve the need to pin in place the magnetic field quanta. Such…”
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Simulating the Trapped B Field in Bulk Superconductors Using a Mutual Inductance Coupling Technique by Davey, Kent R., Weinstein, Roy, Parks, Drew, Sawh, Ravi

“…The field and current induced in a trapped field magnet during a transient current excitation is complicated by the fact that the conductivity of the material…”
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A Study of Pulsed Activation of Trapped Field Magnets-Part 1: Effects of Pulse Height and Creep by Parks, D., Weinstein, R., Davey, K., Sawh, R.

“…We report experimental results of a study of pulsed field activation of YBCO trapped field magnets (TFMs), at 77 K, in which the applied field covers an area…”
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Activation of Trapped Field Magnets by Flux Pumping by Davey, K R, Weinstein, R, Parks, D, Sawh, R

“…High temperature superconducting trapped field magnets (TFM) offer great potential as an alternative to second generation YBCO wire, both in cost and…”
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Characteristics of Trapped Field Magnet Activation by Flux Pumping by Weinstein, R, Parks, D, Sawh, Ravi-Persad, Davey, K

“…Currents are set up in high temperature superconducting (HTS) material when it is cooled in a magnetic field (called field-cooling: FC), or exposed to a…”
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Higher Jc obtained by reduction of pinning potential by WEINSTEIN, Roy, GANDINI, Alberto, SAWH, Ravi, MAYES, Bill, PARKS, Drew

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Nanometer Cerium: A Significant Improvement Over Platinum in Bulk YBCO Superconductor by Sawh, R.-P., Weinstein, R., Parks, D., Obot, V.

“…Large grain YBCO superconductors, containing the same atomic percentage of Ce, and that of Pt, were produced via the melt-texturing process. Samples doped with…”
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Experimental test of the postulate that continuous columnar pinning centers produce the highest by Weinstein, Roy, Gandini, Alberto, Sawh, Ravi-Persad, Mayes, Bill, Parks, Drew

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Experimental test of the postulate that continuous columnar pinning centers produce the highest J c by Weinstein, Roy, Gandini, Alberto, Sawh, Ravi-Persad, Mayes, Bill, Parks, Drew

“…Continuous columnar pinning centers, created by energetic ions, have been usefully studied theoretically and experimentally to investigate vortex physics in…”
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Sub-Micron Non-Superconducting Deposits That Fail to Act as Pinning Centers in Textured YBCO Superconductor by Sawh, R.-P., Weinstein, R., Parks, D., Obot, V., Gandini, A.

“…A conundrum is observed where one type of small, non-superconducting particles fails to provide pinning, in textured YBCO superconductor, while other…”
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Universal Dependence of the Critical Temperature in HTS on the Fractional Volume of Nanosize Defects by Gandini, A., Weinstein, R., Sawh, R., Mayes, B., Parks, D.

“…We report on the effect of randomly-distributed amorphous defects, ~ at the length scale of the superconducting coherence length, on T c in YBCO. These damages…”
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Improved pinning regime by energetic ions using reduction of pinning potential by Weinstein, Roy, Gandini, Alberto, Sawh, Ravi-Persad, Parks, Drew, Mayes, Bill

“…When ion damage is used to create pinning centers, full columnar pinning centers provide the largest pinning potential, U pin, but not the greatest J c or…”
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