Geoscience Reference
In-Depth Information
picture of such an assembly of 10 autoclaves of test-tube type, with one pressure
generator source, operating simultaneously.
Many laboratories throughout the world have this apparatus for studies concerning
phase equilibria, materials synthesis, crystal growth, particles preparation, materials
processing, diamond synthesis, and so on. The recent modifications of these test-tube
bombs have been extended further for higher pressure and higher temperature condi-
tions. The credit goes to the pioneers of this apparatus, Tuttle, Roy, and Licastro, who
could set up a Tem-Press Company to manufacture these autoclaves at Penn State
University. Thus, during the 1950s, the trend in hydrothermal research was toward the
development of new designs, again to attain higher pressure and higher temperature
limits with the better alloys available. This also led to the study of phase relations in
several systems within a broader pressure
temperature range. In this regard, the con-
tribution of Kennedy
[54]
, Morey and Hesselgesser
[55]
, Tuttle and England
[56]
,and
Della Roy and Rustom Roy
[57]
are very important. The SiO
2
a
H
2
O system was stud-
ied in great detail. Followed by this, many other laboratories in Europe, North
America, erstwhile Soviet Union, and Japan took up the study of phase equilibria in
several simple and complicated systems
[57]
. These studies laid a firm foundation for
the ceramists and physical chemists, after many years, to develop a new technology.
At this time, Prof. Yamasaki, Prof. Kumitomi, Prof. Ohara, and Dr. Akitsu were doing
an excellent work in hydrothermal research in Japan. Some of them were closely asso-
ciated with the industries like Toyo Communication Co. Ltd. and Nippon Dempa Co.
Ltd., which resulted in the successful growth of large-size quartz single crystals.
Though they started in a very small way during the postwar period, Japan is now the
largest producer of commercial quartz in the world. Japan alone produces
50% of
.
Figure 2.9 Quartz crystals obtained by Walker
[59]
.
