Silica aerogel

Newly published book chapter - http://link.springer.com/chapter/10.1007/978-3-319-31662-8_4 Aerogels are ultralight solids with nanoporous structure and are one of the world’s lightest materials available in the market. It is a dry gel, principally made up of 99.8 % of air and weighing just around three times that of air. The first aerogels were realized in 1931, when Kistler (J Phys Chem 36:52–64, 1932) attempted to remove liquid from a wet gel.

Newly published book chapter - http://link.springer.com/chapter/10.1007/978-3-319-31662-8_4 Aerogels are ultralight solids with nanoporous structure and are one of the world’s lightest materials available in the market. It is a dry gel, principally made up of 99.8 % of air and weighing just around three times that of air. The first aerogels were realized in 1931, when Kistler (J Phys Chem 36:52–64, 1932) attempted to remove liquid from a wet gel.

Hi 
My question is on what basis do we decide 

1. The dimensions of the sample 
2. The dimensions of the hot and the cold plate 
3. The type of temperature detector sensors used 
4. Heating Source for the hot plate