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A 3 T central field Superconducting Electromagnetic Iron Separator (SEIS), which was designed to separate dangerous ferromagnetic materials, such as detonators, from coal, has been successfully developed at Institute of High Energy Physics (IHEP). The SEIS magnet is mainly composed of a NbTi solenoid coil, a pair of binary current leads (CL) and a re-condensation cryostat with two GM cryocoolers (31 W/40 K, 1 W/4.2 K). Powered with a 250 A/50 V power supply, the magnet has 15 minutes of charging time and 20 minutes of discharging time. The AC losses, mainly consist of hysteretic loss and coupling loss, was calculated with a two-dimensional ANSYS FEA model. The effect of AC losses on the temperature distribution within the cold mass and its induced cryostat pressure rise were analysed during charging process. With regard to the cryostat pressure rise, the analysis results were quite close to the experimental results. [ABSTRACT FROM PUBLISHER]

Magnetic resonance imaging (MRI) requires the gradient coils to produce magnetic field gradients, to encode three-dimensional information. In this work, a parametric method to the design of cylindrical transverse gradient coils for high-resolution magnetic resonance imaging (MRI) is proposed. The cylindrical transverse gradient coil was separated to several turns of curves, each turn is considered as a curve butted by two quasi-elliptic arcs. The parameterized curve is optimized with the simulated annealing algorithm. A cylindrical transverse gradient coil with high level of linearity is designed for 1.5 T MRI system. The cylindrical transverse gradient coil can build a high-quality transverse gradient magnetic field in a large spherical zone, concentric with the main magnet of the MRI system. [ABSTRACT FROM PUBLISHER]

A five-layer superconducting magnet design for 9.4-T whole-body magnetic resonance imaging using an NbTi wire is presented in this paper. In order to control the peak field within the winding region and reduce the consumption of the high-field NbTi superconducting wire, four different conductors were used in four field grades: 9.6, 8.2, 7.0, and 5.2 T, respectively. The 0–1 integer linear programming optimization method was adopted to obtain the final coils' geometries. The design has an inner diameter of 0.95 m and a length of 2.9 m. The field uniformity is better than 5 ppm over a diameter spherical volume of 30 cm with the maximum magnetic field of 9.57 T in the coil region when the center magnetic induction is 9.4 T. [ABSTRACT FROM PUBLISHER]