摘要:

The spinel ceramic material nickel germanate,Ni2GeO4,has been found to exhibit a humidity-dependent impedance. A change in the magnitude of the impedance at 100 Hz, from108&OHgr; at 20&percent;RHto104&OHgr; at 98&percent;RH,at 298 K, is typical. The effect of frequency on the complex impedance has been investigated over the frequency range 10 mHz–10 MHz, using the technique of impedance spectroscopy. The observed impedance spectra show two regions, indicative of an ionic-charge transport process and a charge transfer to the electrodes, suggesting that at high levels of humidity conduction is essentially electrochemical. ©1998 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.121546

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

This letter presents an experimental verification of the super-resolution phenomenon in a nonlinear inverse scattering algorithm, namely the distorted Born iterative method, by using an experimental setup based on a recently developed time-domain ultra-wide-band radar imaging system at the University of Illinois at Urbana-Champaign. The experimental result also demonstrates that the distorted Born iterative method can recover information on the backside of a penetrable scatterer even though scattering data are collected only from limited viewing angles on the front side of the scatterer. ©1998 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.121547

出版商:AIP    

年代:1998

数据来源: AIP