{HEAD ~ A lock} in step can prevent further changes in {TAIL ~ the structure} of the porous multilayer 
{ HEAD ~ A lock } in step can prevent further changes in { TAIL ~ the structure } of the porous multilayer
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH