| 摘要 |
<p>This invention relates generally to silica-alumina ceramic compositions and more particularly to a composition range and process which provides a silica-alumina xerogel having surface areas of up and beyond about two orders of magnitude lower than for compositions outside the range and skeletal densities substantially lower than for compositions outside the range, thereby providing a lightweight silica-alumina material having an essentially nonporous surface and thus, highly advantageous as a coating.</p> |
