الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
The art and science of zone melting is approximately three decades old, but it can proudly boast to be responsible for
many of the spectacular advances in almost every branch of solid state science. It has provided research scientistis with
a variety of crystalline materials at undreamt sparse levels of impurities and thus opened up the studies of properties of
many materials which, until the advent of zone melting, had been
impaired or prevented by the presence of offensive levels of
(1) impurities in the materials available then
The general term zone melting denotes a family of methods
for controlling the distribution of soluble impurities or
solutes in crystalline materials.
In all these methods a short molten zone travels slowly through a relatively long solid charge, and while traveling,
redistributes the solutes in the charge. If the number, size, and travel direction of the zones, as well as the initial make
up of the charge, are suitably chosen, many useful and some- times remarkable operations can be performed on the charge (2)
The impurity concentration is generally required to be
varied in one or more of the following ways.