Observation of an Electromagnetically Driven Temperature Wave in Porous Zinc Oxide During Microwave Heating
D. Dadon,1 D. Gershon,2 Y. Carmel,2 K. I. Rybakov,2,4 R. Hutcheon,3 A. Birman,2 L. P. Martin,1
J. Calame,2 B. Levush,2 M. Rosen1
1Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD
2Institute for Plasma Research, University of Maryland, College Park, MD
3 Chalk River Laboratories, Chalk River, Ontario K0J1J0, Canada
4Permanent address: Institute of Applied Physics, Nizhny Novgorod, Russia
Materials Research Society 430, 507-512 (1996)
ABSTRACT. Propagation of a sharp temperature wave was observed during microwave heating of porous zinc oxide in nitrogen and argon atmospheres. This wave initiated from the center of the sample and traveled at an average velocity of 0.2 cm/min towards its surface. This temperature wave was attributed to an anomalous peak in the imaginary part of the complex permittivity possibly caused by desorption of chemisorbed oxygen from the surfaces of ZnO crystallites.