Crack during drying

Warping and Cracking during Drying TABLE 14A Evaporative Drying of a Flat Green Body... 

After electrophoresis, gels are stained with Coomassie blue, destained and equilibrated with 30 % methanol/ 2 % glycerol (to avoid cracking during drying). 

Multiple dipping finally increases the maximum allowable thickness of the (calcined) crack-free membrane with respect to that obtainable in a single step [13,14,18]. At each given set of experimental conditions there is a certain critical layer thickness which should not be exceeded if cracking during drying and/or calcination is to be avoided. 

The question of the original location of the cracks must be adressed. Cracks during drying occur from microflaws expected to be present on the surface of the gel. Regarded as a whole, the network is under compression stress. However, Scherer [22] demonstrated that at the extremity of the flaw tips the solid part remains in tension. 

There is often a large volume shrinkage and cracking during drying (we have to remove... 

In practice, there is a limit to layer thickness (and hence mask thickness) determined by the tendency of thick layers to crack during drying. At the other extreme. 

Highly elongated forms of silica, other than fibers formed from glass, have bee-obtained either by conversion from fibrous precursors or by unidirectional craz- ing or cracking during drying of thin films of sols. 

Painting [4, 79, 80] In the painting mefliod, the catalyst ink is painted directly onto a dry membrane in the Na form. Caution should be taken to avoid distortion and cracking during drying. 

Preparative siJica gel plates are available precoated with a layer thickness of 500-2000 Use of these plates avoids the problems associated with preparing thick layers in the laboratory, most notably the formation of cracks during drying of the spread adsorbent slurry. Analtech offers a unique tapered layer for preparative separations (see Section V.D below). 

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