  Gaseous electronic characteristics due to cosmic ray ionization in the
electrode systems with ZnO and carbon nanostructures have been examined in
atmospheric Ar/N2 and O2/N2 mixtures. The electric conductivity at the quasi
linear stage is measured at the level of 10-11~10-10 S/m, 4~5 orders of
magnitudes higher than that of the samples without nanostructures, which is
construed by the 108~1010 times increment of the cosmic ray ionization
frequency. The results are consistent with the hypothesis that the role of
one-dimensional nanostructures in this gaseous electronic phenomenon is based
on the intensive field gradient effect, rather than the field enhancement
effect.
