摘要 |
<p>The container (10) includes a feed device (11, 12) to supply material inducing thixotropy in the liquid. The feed device is arranged so that on the basis of a signal from a signal transmitter, the material inducing thixotropy is supplied to the container, so that at least a closed layer of the liquid becomes thixotropic and impermeable to the rest of the liquid.</p> |