Conducting an investigation on simulation of a ball lightning, we many times could be convinced that rather steady plasmalike objects contain a filamentary basis. The presence of one would induce the appearance of large structural leavings after relaxation of the objects.

It was also at the time of studing on so-called "jumping balls" ten years ago. The flight of a burning tin ball created with the help of a capillary discharge was followed by formation of fireball leaving a smoke trail, which would become diffuse in an atmosphere not at once but with some delay. It could be explained by existence within a smoke of some rigid basis during restricted time, however the obtaining of the steady structural leavings was not successful. At last after considerable augmentation of a discharge current the smoke trail began to take the form of a cord which during some seconds was torn to the pieces that were quickly shrinked and gave a steady structural residual. (Fig.1). It consisted of chaines of light and dark balls by a diameter about 1 micron, and along an axis there was the lengthy thread of only dark balls.

At first the combustion of polyethylene in an atmosphere is not followed by formation of large smoke particles: one can't descry anything on a light microscope's object-plate smoked by its flame. Having been heated enough during burning, the polyethylene begins to fume, and with the helping of a light microscope one can find separate aggregates, dimensions of which are usually less than 100 microns (Fig.1).

If to bring in burning polyethylene into electric discharge between two wire electrodes, for example, at a voltage of 5kV with the resistor of 50 kOhm at a current about 50 mA, the process of burning absolutely changes. Some seconds later the ambient volume is filled by black flakes measuring up to 10-20��. When using of the discharge under a surface of melted paraffin (Fig.2) the sizes of aggregates are more modest and comparable to a diameter of threads.

Located above the discharge, the lower face of an object-plate is being covered by relaxing and shrinking structures. Therefore the exemplar's consistence depends on height of a glass locating above the discharge (Figs. 3, 4, 5). In figures the light smoked deposit of an oxide of aluminum - material of electrodes is seen.

Idiosyncrasy of frames is the rather dense body consisting of thin "stuck round" threads (Fig.7) and branchs thrown outwards (Fig.6).

Being caught by object-plate's glass before completion of a relaxation, the frames contain more "pure" threads. They can organize a grid, rings (���.8) or be situated separately (���.9).

In addition to aggregates among products of the discharge it is possible to find a metal-containing fiber. Out of the endings of tape filaments the "wire" can protrude, and the cylindrical filaments can be similar to bamboo (Fig.10). In case of steel electrodes the threads show magnetic properties.

To get structural leavings at the stage of development of threadlike structures it is necessary to limit the action of burning-through. It can be achieved by increase of a discharge voltage at the current's magnitude unchanged: U = 25kV, R = 250kOhm; upper ending of a negative electrode is disposed below a paraffin surface and the positive electrode is aside and above it. Being combusted and burned-through by electrical current, the paraffin jets appear above a cathode and exist during the discharge. Now the leavings contain a lot of paraffin and the carbonic threads are only forming. In Fig.11 one can see a flattened out drop having a carbonized inclusions. In Figs.12, 13, 14 the leavings in which a burning-through and structuring came further are presented: the thin structure is absent within the region of main contents of paraffin. On pictures made in polarized light it is seen that the metal-containing polymer is almost absent in a thread's thickness range accessible via given method.

Some effects in capillary discharge's plasma

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