Surface free energy (SFE) plays an important role in microfluidic device operation. Photosensitive glasses such as APEX offer numerous advantages over traditional glasses for microfluidics, yet the SFE for APEX has not been previously reported. We calculate SFE with the Owens/Wendt geometric method by using contact angles measured with the Sessile drop technique. While the total SFE for APEX is...

A Bol loop is a that satisfies the identity x((yz)y)=((xy)z)y. In this paper, we give construction of free loops exponent two. We define canonical form all their elements and describe multiplication law based on form.

We present a generalization of context-free grammars to twodimensions and define picture languages generated by these grammars. We examine some properties of the formed class and we describe how these languages can be recognized by two-dimensional forgetting au-