Прочитайте следующие предложения, а затем сделайте краткий доклад на русском языке об алюминии.

1. Aluminium alloys can possess the strength of steel, though only a third the weight. 2. Cows give more milk when there are cool, heat-reflecting aluminium roofs on their dairy barns. 3. Aluminium offers a bright hope for energy conservation. 4. In direct contact with a heat source, aluminium is an excellent conductor. 5. World's lightweight champion in the long-distance transport of electricity, aluminium, has virtually replaced heavier copper in high-voltage power lines. 6. Nearly indestructible, aluminium can be remelted over and over. 7. Aluminium is alloyed with small amounts of other metals. 8. Copper adds strength; magnesium imparts additional marine-corrosion resistance.9. Unlike copper or iron, aluminium does not occur naturally in metallic form. 10. Aluminium exists only in combination with other elements, primarily oxygen, with which it forms an extremely hard oxide known as alumina. When tinted by traces of other elements, alumina can take the form of gems such as rubies and sapphires. 11. Constituting 8 per cent of the earth's crust, aluminium is the most abundant of metals, as well as one of the hardest to produce. 12. Even fly ash from coalbuming furnaces could become a source of aluminium. 13. Subduing the waves, aluminium alloys not only combine lightness with strength but stoutly resist salt water's corroding effect. 14. When we recycle aluminium, we save 95 per cent of the energy needed to make new metal from bauxite. IS. Once you make aluminium it becomes an energy bank that you can tap over and over again. 16. The uses of aluminium are almost illimitable. 17. Aluminium panels sheathe the World Trade Center in New York. 18. Builders can use aluminium nails, and bolts to install aluminium storm doors, screens, flashing, gutters, downspouts, shingles, awnings, and Venetian blinds - some 200 building products in all. 19. In 1884, when aluminium was still as valuable as silver, a hundred-ounce tip of the metal was chosen by architects to finish the 555 ft high Washington Monument in Washington, D. C, USA.

pavlon4kp0bmeh    2   03.03.2020 10:47    0