One is hierarchical pores, and the other is a macro molecular nanoscale porosity in the material.

Aquifer means a subsurface layer or layers of geological strata of sufficient porosity and permeability to allow either a flow of or the withdrawal of usable quantities of groundwater.

Because of the porosity of the borders and the historically fluid nature of the conflict in the subregion, we will feel safe and secure only in a conflict free region.

Aquifer means a subsurface layer or layers of rock or other geological strata of sufficient porosity and permeability to allow either a significant flow of groundwater or the abstraction of significant quantities of groundwater.

The scourge is also striking the transit countries, themselves afflicted by the porosity inherent in these networks of corruption the trade routes of drug trafficking follow the lines of least political, economic and social resistance.

The difficulties include the porosity of borders, the lack of material and financial support and the fact that some officials do not have the genuine political will to achieve integration and unification, all of which undermine the situation with respect to security, political, administrative, economic, social and humanitarian matters.