US  5,322,821 <br/>
Porous ceramic beads. 

 -  Jun. 21, 1994 
<br/><br/> JP-1349/TH-166 
<br/><br/><label>Subjects--Local Terms: </label><br/>POROUS CERAMICS <br/>FILTER <br/>BEADS, CERAMIC <br/>CERAMIC BEADS 
<br/><br/><label>Call Number: </label>US 5,322,821