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A superconductor is an element, inter-metallic alloy, or compound
that will conduct electricity without resistance below a certain
temperature. When it comes to the uses of superconductors, there are
several different ways for them to be used. Magnetic-levitation is an
application where superconductors perform extremely well. Transport
vehicles such as trains can be made to “float” on strong
superconductors magnets, virtually eliminating friction between the
train and its tracks.
An area where superconductors can perform a life-saving function is
in the field of biomagnetism. Doctors need a non-invasive means of
determining what’s going on inside the human body. By impinging a
strong superconductor-derived magnetic field into the body, hydrogen
atoms that exist in the body’s water and fat molecules are forced to
accept energy from the magnetic field. They then release this energy at
a frequency that can be detected and displayed graphically by a
computer. An example of this could be a MRI, which stands for Magnetic
Resonance Imaging. This type of test was actually discovered in the mid
1940’s.
Probably the one event, more than any other, that has been
responsible for putting “superconductors” into the American lexicon was
the Superconducting Super-Collider project planned for construction in
Ellis county, Texas. Though congress cancelled the multi-billion dollar
effort in 1993, the concept of such a large, high-energy collider would
never have been viable without superconductors. High-energy particle
research hinges on being able to accelerate sub-atomic particles to
nearly the speed of light. Superconductor magnets make this possible.
Another use of superconductors is in electric generators made with
superconducting wire are far more effeicient than conventional
generators wound with copper wire. In fact, their efficiency is above
99% and their size is about half that of conventional generators.
General Electric has estimated the potential worldwide market for
superconducting generators in the next decade at around $20-30 billion
dollars. Other commercial power projects in the works that employ
superconductor technology include energy storage to enhance power
stability. An idealized application for superconductors is to employ
them in the transmission of commercial power to cities. However, due to
the high cost and impracticality of cooling miles of superconducting
wire to cryogenic temperatures, this has only happened with short “test
runs.”
The most ignominious military use of superconductors may come with
the deployment of “E-bombs.” These are devices that make use of strong,
superconductors devired magnetic fields to create a fast,
high-intensity electro-magnetic pulse (EMP) to disable an enemy’s
electronic equipment. According to various estimates, the worldwide
market for superconductor products is projected to grow to near $90
billion by the year 2010-and $200 billion by 2020. This is, of course,
contingent upon a linear growth rate. Should new superconductors with
higher transition temperatures be discovered, growth and development in
this exciting field could explode virtually overnight.
Superconductors, materials that have no resistance to the flow of
electricity, are one of the last great frontiers of scientific
discovery. Not only have the limits of superconductivity not yet been
reached, nut the theories that explain superconductor behavior seem to
be constantly under review.
The type 1 category of superconductors is mainly comprised of pure
metals that normally show some conductivity at room temperature. They
require incredible cold to slow down molecular vibrations sufficiently
to facilitate unimpeded electron flow in accordance with what is known
as BCS theory. Type 1 superconductors-also known as the “soft”
superconductors-were discovered first and require the coldest
temperatures to become superconductive. Ironically, copper, silver, and
gold, three of the best metallic conductors, do not rank among the
superconductive elements in the type 1 category.
Except for the elements vanadium, technetium, and niobium, the type
2 category of superconductors is comprised of metallic compounds and
alloys. The recently-discovered superconducting “perovskites” belong to
this type 2 group. They achieve higher Tc’s than type 1 superconductors
by a mechanism that is till not completely understood. Although, other
recent research suggest that hole of hypocharged oxygen in the charge
reservoirs are responsible.
Now, to let you know who created superconductors and what year these
useful things were created. In 1911, superconductivity was first
observed in Mercury by Dutch, physicist, Heike Kamerlingh Onnes of
Leiden University.
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