| 摘要 |
<p>A device for controllably delivering a material into an aqueous medium, the device comprising a soluble portion which is adapted, in use, to dissolve in an aqueous medium thereby to deliver into the aqueous medium a material which is retained in the device, the soluble portion comprising a soluble phosphate glass having a P2O5 content of from 40 to 50 mole %, and constraining means which are located in the vicinity of the soluble portion and which are arranged, in use, to constrain a stationary liquid layer between the soluble portion and the constraining means. The invention also relates to a method of controllably dissolving a soluble phosphate glass in an aqueous medium.</p> |
