Tuesday, October 25, 2011

Recent researches have turned representations of scientists aboutability of loose substances to maintain pressure

By scientists it has been established that the surface of a loose mix can sustain weight which stays in considerable dependence on coordination number of each particle of a part mix.
By scientists it has been established that the surface of a loose mix can sustain weight which stays in considerable dependence on coordination number of each particle of a part mix.

Thanks to presence of stable structures which are in each loose substance, they can sustain weight of other objects on the surface. These stable structures consist of separate parts which are called as "bridges". Results of last research of the German scientists have shown that the limit of weight which such "bridges" can keep a little depends on external forces, for example, from gravitation or interaction among themselves separate particles. Proceeding from the analysis of the received data, it turns out that influence on weight keeping, renders only average of neighbours of each particle. To prove the assumptions, scientists had to create three dimensional structure kolloidnyh solutions as their parametres have property to change in rather broad range in comparison with dry mixes.

At first sight, loose substances, for example, as sand, seem homogeneous, but actually all at all so. For example, pressure of grain upon barn walls in different places, will be a miscellaneous, and "stoppers" in pipes or trenches on which sand arrives, make direct impact, on it transforming into a firm body.

Throughout the long period of time, whether scientists could not define there is a communication between an arrangement of particles in space and components of a loose mix. To understand it, it was necessary to study the loose substances which surface can sustain the big weight.

If to follow elementary physical laws the weight of object which is at top of a heap of sand cannot be divided fifty-fifty between all particles. Actually, the object is kept only at the expense of those particles which take direct part in formation of same "bridges" that carry out mutual stabilizirovanie among themselves in certain directions. Placing of "bridges", is carried out by different principles. The most widespread mechanism of their placing, is what reminds bricks in the arch arch.

For the purpose of a similarity establishment between these so-called "bridges", group of researchers of one of the German universities, spheres in diameter 2 microns have been used. These spheres have placed in transparent liquids of different structure. Thanks to created in such way kolloidnym to systems, scientists had an opportunity by means of a microscope to observe the phenomena which occur in case of change of conditions in broad range, that is, changed liquid type, quantity of particles. Thus, kolloidnaja the system turned to a loose mix which received ability to maintain some weight on the surface.

Some time ago, the same group of researchers has developed algorithm which has helped to establish particles a part of three dimensional "bridges". After detection of bridges, scientists have begun search of various similarities in any systems having different characteristics.

Soon, results of researches have led to a conclusion that "bridges" obrazovyvajutsja under the influence of coordination number, that is, average of neighbours of each particle. Such result of the spent experiences became a bolt from the blue for scientists. After all earlier was considered that on keeping of some weight on a surface of loose substances, properties of the substance influenced. Though certainly, it is necessary to notice that it is impossible to reject this opinion completely.

Alexander Smoly

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