Historical reference
In the USSR under the guidance of E.I. Zababahin the scientists of NIITF K.V.Volkov, V.V. Danilenko and V.I. Elin synthesized diamonds by implied compression of graphite and soot in spherical and cylindrical ampoules, and in 1963 to increase the diamond production there was used compression of a mixture of graphite and metal-cooler. In 1962 Danilenko suggested changing the ampoule synthesis by non-ampoule with explosion in explosion chamber. At the same time graphite was put into the cylindrical charge made of an alloy of trotyl/gexagen TG 40, and to suppress graphitization and decrease of discharge rate of the forming diamond the charge was surrounded by a water casing. This provided a drastic increase of diamond production. A trial experiment with the charge without graphite was carried out in July 1963 and it confirmed the assumption of diamond synthesis from carbon products by explosion. On the basis of a phase diagram of carbon and P, t numbers at Zhuge point during the explosion decomposition of explosives it was shown that free carbon should condense in the form of diamond. And the explosive should have a negative oxygen balance.
The main advantage of condensation of atomic carbon in explosion products compared to synthesis from graphite is that in this process there is no need of power consumed and time needed to destroy or reconstruct the initial crystalline graphite lattice. In this case the problem is not to allow ultra-dispersed diamond (UDD) to oxidize and graphitization. In 19631965 there was demonstrated a significant role of cooling the by transforming potential energy of PG40 into kinetic power of the coating, surrounding the charge. The charge of PG40, produced in the form of extended cylinder produced UDD 8-12 % of the charge mass with the amount of UDD in the charge up to 75 %. In the USA the first report about UDD synthesis appeared only in 1988. Their content in soot as the authors reported was 25 %. Thus Russia has priority of invention synthesis of detonation nano-diamonds. However, despite a number of successful experiments in the beginning of 1960s further research was practically stopped because of a very intensive development of production of diamonds in catalytic synthesis, while introduction of new methods of UDD synthesis was hampered. In 1982 ND synthesis was carried out in a few scientific centers of the USSA. But production capacity was critically larger than demand in ND. In 1993 a number of productions were closed and until 2003 they didnt resume working. Lately the DND became the subject of interest of researchers again.



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