Контрольная работа № 8 Вариант b

1.

This label “Made in Space” for industrial materials will probably surprise no one in the not so distant future. They may include superconductors, new kinds of alloys, substances with peculiar magnetic properties, polymers, plastics and so on. Numerous experiments carried out at the Russian orbital space stations have paved the way to the development of methods and means for industrial production of new materials with better qualities. Experts estimate that within a few coming years industrial production of various materials will be started in space.

2.

Conditions on board a space vehicle orbiting the earth greatly differ from those on its surface. All of these conditions can be simulated on the Earth, except for one prolonged weightlessness. Weightlessness can be created on the Earth, but only for a few seconds. A space flight is another matter. a satellite orbiting the earth is in a dynamic zero gravity state, i.e., when gravity is cancelled out by inertia. Many well-known processes go on differently due to the absence of weight.

3.

In space there is no gravitational connection, i.e., movement of gases or liquids caused by difference of temperatures. It is well known that various defects in semiconductors occur because of convection. Biochemists also have to deal with the worst aspects of convection, for example, in the production of superpure biologically active substances. Convection makes it very difficult to produce them on the Earth.

4.

Following the launching of the first orbital station the specialists started experiments aimed at proving the advantages of the zero gravity state for the production of certain materials. In Russia all orbital stations from Salyut 5 onwards were used for that purpose. Since 1976 over 600 technological experiments have been carried out on board manned and unmanned space vehicles. The experiments proved that many of the properties of the materials obtained under the zero gravity condition were much better than those produced on the Earth. Besides, it has been found out that it is necessary to develop a new science – physics of the weightless state – which forms the theoretical basis for space industry and space materials study.

5.

Special space vehicles will also be needed for industrial production of new generation materials. Research has shown that the acceleration rate on board these vehicles must be reduced to the minimum. It was found that space platforms in independent flight carrying the equipment were most suitable for producing materials. These vehicles will have to use their own propulsion systems to approach their base orbital station after a certain period of time. The cosmonauts on board the station can replace the speci

mens.

6.

Many new and very interesting projects are planned for orbital stations. Here is one of them. Convection does not allow to grow large protein crystals on the Earth. But it is possible to grow such crystals under the zero gravity conditions and to study their structure. The data obtained can be useful for genetic engineering. Thus, it may be possible to make new materials in space and also to obtain valuable scientific data for new highly efficient technologies on the Earth.