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(EX/P3-05) Observations of Skeletal Microstructures in Various Types of Dust Deposit in Tokamak T-10

B.N. Kolbasov1), A.B. Kukushkin1), V.A. Rantsev-Kartinov1), P.V. Romanov2)
1) NFI RRC ``Kurchatov Institute'', Moscow, Russia
2) Ministry of Russian Federation for Atomic Energy, Moscow, Russia

Abstract.  An analysis of electron transmission and scanning micrographs of various types of dust deposit in tokamak T-10 is carried out for (a) analyzing the origin of non-trivial (e.g. cauliflower-like) structures in dust deposits, and (b) verifying the former hypothesis for possibility of self-assembling, during electric breakdown, of skeletal macrostructures from wildly formed carbon nanotubes. The results (Phys. Lett. A, 269 (2000) 363; 291 (2001) 447) show (i) presence of tubular structures in the range of diameters D $ \sim$ 5 nm - 10 microns; (ii) trend of assembling bigger tubules from smaller ones (i.e., the self-similarity); (iii) ability of nanotubular structures to build up the skeletons of various topology, including the tubules, cartwheels, dendrites; (iv) presence of an amorphous component which may hide the internal skeleton either fully (to give a solitary dust particle) or partly (to give an agglomerate of visually separate particles); (v) similarity of structures in dust deposits, in the range D < 10 microns, and in the images taken during electric breakdown in various types of discharge (tokamak, plasma focus, Z-pinch), D $ \sim$ 100 microns - 10 cm.

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IAEA 2003