LEXINGTON,
Ky.- Membranes composed of manmade carbon nanotubes
permit a fluid flow nearly 10,000 to 100,000 times
faster than conventional fluid flow theory would
predict because of the nanotubes' nearly friction-free
surface, researchers at the University of Kentucky
report in the Nov. 3 issue of Nature.
In their study, Mainak Majumder, Nitin Chopra and
Bruce J. Hinds of UK's Chemical and Materials Engineering
Department, and Rodney Andrews of UK's Center for
Applied Energy Research found the flow dynamics of
carbon nanotube (CNT) membranes with pores measuring
7 nanometers in diameter permit a fluid flow exceeded
the flows predicted by conventional hydrodynamic
predictions.
In
their study "Enhanced Flow in Carbon Nanotubes," the
researchers note an "aligned CNT membrane has fast
transit approaching the extraordinary speed of biological
channels. The membrane fabrication is scalable to
large areas, allowing for industrially useful chemical
separations.
"(E)ach side of the membrane can be independently
functionalized. These advantages make the aligned
CNT membrane a promising large-area platform to mimic
protein channels for sophisticated chemical separations,
trans-dermal drug delivery and selective chemical
sensing," the researchers say.
Cadmium
selenide has been studied for applications in optoelectronics,
luminescent materials, lasing materials and biomedical
imaging. It is perhaps best known as the basis
for quantum dots that have applications in biomedical
imaging.
Zinc oxide is a semiconducting, piezoelectric and optical material with potential
applications in sensors, resonators and other nanoelectronic structures. The
systematic study of growth parameters for these structures involved more than
100 experiments and was published in the Journal of Physical Chemistry (B,
Vol. 109 (2005) 9869-9872).
“Now that we have determined the optimal requirements for growth, it should be
straightforward to scale up the production of these structures,” Wang concluded. “We
have a lot of ideas for potential applications.”
Source: Georgia Institute of Technology
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