ответьте письменно на следующие вопросы по тексту: 1. When was niobium discovered? 2. Where is it used? 3. Where can deposits of columbite be found? 4. What trouble has sand been causing since oil was discovered in the Sahara desert? 5. Why do people export Norwegian sand to the Sahara desert?
Niobium
Here is a short story about niobium or columbium. In 1801 Charles Hatchett, an English chemist, analyzed an ore sample which had been sent to the British Museum from the United States. He named it "columbium" after Christopher Columbus. And the columbium-ore was given the name of "columbite".
But in 1844 this metal or metallic element was rediscovered by Rose. And because it looked like tantalum it was named "niobium" after Niobe, the daughter of Tantalus, and the mytholo¬gical goddess of tears.
But the new name (niobium) was not immediately accepted. And only after more than 100 years of controversy, it was adopted by the International Union of Pure and Applied Chemistry in 1950.
Today American scientists refer to the metal as "niobium". But, most American metallurgists and producers of the metal use the name "columbium". For many years niobium was not only useless, but it was, in fact, a nuisance. Chemists looked upon it as an impurity in the ores of important metals.
In recent years metallurgists discovered that niobium was an excellent alloy for strengthening many kinds of steel, and that in resistance to heat and corrosion it was a miracle-metal.
Now niobium is beginning to be used in making synthetic silk, as well as in aircraft industry.
But since it is still a rare metal its uses are limited.
Is it found in many parts of the world? Not at all. Deposits of columbite, its ore, are worked in Australia, Africa (Nigeria and Congo-Kinshasa), in the Kola Peninsula (Russia), Canada, Brazil and Norway.
It's Interesting To Know
Ever since oil was discovered in the Sahara and other desert areas, the engineers have been troubled by one thing - sand! It blows into the pipes which bring the oil from the desert to the ports for shipment, and causes the pipes to become clogged!
So you'd imagine that the last thing an oil engineer wants is sand! But, believe it or not, people are actually digging the stuff up on the beaches of Norway and exporting it to - of all places - the Sahara desert! The reason? Because Norwegian sand is very fine and has been found to be the best possible material for cleaning out oil pipes which have been clogged by the much coarser sand of the Sahara! So sand has to be sent thousands of miles to cure the trouble which has been caused by - sand!
It's a strange world, isn't it?

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