摘要 |
PCT No. PCT/GB89/01485 Sec. 371 Date Aug. 12, 1991 Sec. 102(e) Date Aug. 12, 1991 PCT Filed Dec. 12, 1989 PCT Pub. No. WO90/06804 PCT Pub. Date Jun. 28, 1990.Filtering apparatus for the separation of microparticles such as bacteria has two planar sheets each with an array of laser drilled or etched pores. One or both of the sheets can be displaced relative to the other under feedback control to bring the pores into greater or lesser register. The effective pore size is thus varied to provide controlled selectivity. |