A method of isolating semiconductor devices formed on a semiconductor substrate having a silicon on insulator layer is provided. A zone group table includes entries for different pairs of zones, wherein each entry indicates whether access between a pair of the zones is permitted. The apparatus may also generate an IEEE 802. The electrons injected into the graphene material base layer can be \u201chot electrons\u201d having an energy E substantially greater than EF, the Fermi energy in the graphene material base layer or can be \u201cnon-hot electrons\u201d having an energy E approximately equal to than EF. The valve seat is moved in response to an elevated level of the pressure of brake fluid into engagement with the valve, so that the check valve is closed.