| 摘要 |
<p>An apparatus for forming a tubular structure from a liquefied polymer, theapparatus comprising: (a) a dispenser for dispensing the liquefied polymer;(b) a precipitation electrode being at a first potential relative to thedispenser, the precipitation electrode being designed and constructed forgenerating a polymeric shell thereupon; and (c) a mechanism for increasinga local density of the polymeric shell in a plurality of predeterminedsub-regions of the polymeric shell, thereby to provide a tubular structurehaving an alternating density in a longitudinal direction.</p> |
