Дарья99911
24.10.2020 20:01

Пересказ текста на (8 предложений) надо.made in space 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, supertransparent laser glass, 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 of industrial production of new materials of better quality on board a spacecraft. experts estimate that within a few coming years industrial production of various materials will be started in space. conditions on board a space vehicle orbiting earth greatly differ from those on its surface. however, all of these conditions can be simulated on earth, except for one — prolonged weightlessness. weightlessness can be created on earth, but only for a few seconds. a space flight is another matter: a satellite orbiting earth is in a dynamic zero-gravity state, i.e., when gravity is cancelled out by inertia. what can weightlessness be used for? many well-known processes go on differently due to the absence of weight. the archimedes principle is no longer valid and, consequently, stable-state liquid mixtures can be obtained, the components of which would immediately separate on earth because of different density. in case of melts of metals, glasses or semiconductors, they can be cooled down to the solidification point even in space and then brought back to earth. such materials will possess quite unusual qualities. in space there is no gravitational convection, i.e., movements 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 on earth. following the launch of the first orbital stations the specialists started experiments aimed at proving the advantages of the zero-gravity state for the production of certain materials. in this country all orbital stations from salyut 5 onwards were used for that purpose, as well as rockets. 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 earth. besides, it has been established 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. this science has basically been developed. the methods of mathematical modelling of the hydromechanical process under the zero-gravity condition have been created with the help of computers. 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 specimens. 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 earth. but it is possible to grow such crystals under the zero-gravity condition and to study their structure. the data obtained during the experiments can be useful for the work of laboratories on earth in using the methods of gene 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 earth. preparatory work for industrial production in space at a larger scale is being carried out in russia, the usa, western europe and japan. it should be said that according to the estimates of american experts production of materials in space is to bring 60 billion dollars in the future.

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викусик150
28.08.2021 09:33

перевод:A. Во всех странах есть неписаные, но важные правила поведения, которые могут быть объясненным людьми, которые живут в этой стране. Но они могут действовать иначе в одной и той же ситуации: «Когда англичан знакомят с каждым другие, они пожимают друг другу руки и спрашивают: «Как поживаете?». А они? Иногда да. Но в жизни не так уж и торжественно. Так что я могу дать тебе только общие советы. Без правил. Мы помним, что иностранцы не знают наших путей, и пока вы дружелюбны и вежливы от души, мы не против вы ведете себя немного странно. Информация о правилах поведения обычно верна для многих, но не для всех. Редко можно описать нацию такими словами, как «Все британцы сделай то или это. " Лучше сказать: «Некоторые британцы ...» И мы иногда не уверены, как действовать, и не можем сказать вам, как действовать в этом или та ситуация. Вы можете узнать, что, отвечая на вопросы, мы часто ответ: «Ну, это зависит от обстоятельств. 39,

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emdnick
25.05.2022 14:26
My Favourite Day My name is Alexey and I’m fourteen years old. I’d like to tell you a few words about my favourite day of the week. It is Saturday, of course, because on this day my weekend starts. We have a six-day school week, so on Saturday morning I still study. However, starting from the afternoon I’m free till Monday. My friend has once asked me why I like Saturday more than Sunday and I exactly knew the answer. First of all, on Saturday I don’t have to worry about going to bed late. On week days, my parents tell me that I should go to bed early not to be late for school next morning. Even on Sunday they don’t allow me to stay longer than 10 pm, because I have to wake up early on Monday morning. That’s why I like Saturdays more. We don’t usually have many classes on this day, only a few. After that, I meet up with my friends and we go to the local sports ground. Depending on weather, we can play football, volleyball or other outdoor games there. If we are in the mood for pizza or hot-dog, we go to the nearest cafe. In the evening I’m allowed to invite my friends over for a movie or a computer game. Sometimes we play interesting board games. When my friends leave, I can still do whatever I like, for example, play with my hamster, read a book or help my mum to cook something delicious. The main thing is that I can stay up as long as I wish. Sundays are also fun. Sometimes we visit our relatives on this day and I get to play with my cousins. In the evening I have to do my homework and get ready for the school week. By the way, I like weekends even more when they are tied up with special occasions or holidays.
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