That could be because the samples of the material are, as Ashoori says, "super dirty"; purer samples might exhibit less electrical resistance.
Comets are dark objects of ice, dust and rock that are believed to contain pristine samples of the material from which the solar system was formed some 4.6 billion years ago.
The researchers subjected samples of the material extracted by Dr. Schweitzer to an examination by mass spectroscopy, which breaks down material to its component parts to determine its mass and chemical makeup.
Recent samples of the material synthesized by their research group produced some unanticipated results, according to David Muller, professor of applied and engineering physics who analyzed the samples' atomic structures with his state-of-the-art microscope.
In the first step, spherical nanoindentation measurements are conducted on fully annealed samples of the material of interest to map out the functional dependence of the indentation yield strength (Yind) on the crystal lattice orientation in the annealed condition.
Translucent photomicrographs of samples of the material obtained from the iron catalyst show that the material consists of multi-walled carbon nanotubes (CNTs) with an outer diameter of up to 300 nm (Fig. 1).
