| 摘要 |
<p>A device for transporting magnetic particles in a selected direction has a support surface extending in the selected direction, a magnet arranged to generate a magnetic field for retaining the particles on the support surface such that the magnetic field on the support surface has high- and low-field bands and a magnetic field gradient zone between the high- and low-bands, means for advancing the high- and low-bands relative to the support surface in a direction having a component in the direction of the gradient, wherein along the high-field band at least first and second magnetic poles of opposite polarity are arranged such that a first magnetic path on the support surface from the first pole to the second pole is shorter than a second magnetic path on the support surface crossing the gradient zone from the first pole to any other nearest pole of opposite polarity.</p> |
