A possible theory of an open membrane is proposed. The space-time coordinates, swept out by the membrane, are denoted as X"(<1°, <1 1, <1 2) where <1" are parameters. A simple Lagrangian which is invariant under there-parametrization 0" 0-7<1°'(<1), <1 1'=<11 and <1 2'=<12 is set up and the equations of motion and the boundary conditions are derived. After the gauge is fixed, they are solved in...

this is a comprehensive review of the recent progresses made in the field of zeolite membranes. it describes zeolitic materials and methods of membrane fabrication, followed by a summary of applications for gas separation, pervaporation and separation of liquid mixtures. special attention is called to polymer mixed matrix membranes (mmms) and membranes based on metal organic frame works (mofs)....