“…Microwave techniques have been used to measure and monitor changes in the electromagnetic properties of materials [ 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 ]. Microwave measurements can be very sensitive and can be used remotely through many different media to non-invasively monitor the sensing material’s response to its environment.…”