| 摘要 |
<p>The device (P) has a retaining element (18) in which inorganic binding agent systems are located. Two walls (1, 2) are provided with respective probes (15.1, 15.2) such that chambers (10.1, 10.2) are provided between the binding agent systems and the probes for a contact material. Two membranes separate the binding agent systems from the contact material, and follow the binding agent systems during shrinking of the binding agent systems. The probes are alternatively interchangeable in functions as sound generators and/or sound receivers.</p> |
